cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Role of the temperature instabilities for formation of nano-patterns upon single femtosecond laser pulses on gold
Creators: name: Gurevich, Evgeny L.
name: Levy, Yoann
name: Gurevich, Svetlana V.
name: Bulgakova, Nadezhda M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: In this paper we investigate whether the periodic structures on metal surfaces exposed to single ultrashort laser pulses can appear due to an instability induced by two-temperature heating dynamics. The results of two-temperature model (TTM) 2D simulations are presented on the irradiation of gold by a single 800 nm femtosecond laser pulse whose intensity is modulated in order to reproduce a small initial temperature perturbation, which can arise from incoming and scattered surface wave interference. The growing (unstable) modes of the temperature distribution along the surface may be responsible for the LIPSS (Laser Induced Periodic Surface Structures) formation. After the end of the laser pulse and before the complete coupling between lattice and electrons occurs, the evolution of the amplitude of the subsequent modulation in the lattice temperature reveals different tendencies depending on the spatial period of the initial modulation. This instability-like behaviour is shown to arise due to the perturbation of the electronic temperature which relaxes slower for bigger spatial periods and thus imparts more significant modulations to the lattice temperature. Small spatial periods of the order of 100 nm and smaller experience stabilization and fast decay from the more efficient lateral heat diffusion which facilitates the relaxation of the electronic temperature amplitude due to in-depth diffusion. An analytical instability analysis of a simplified version of the TTM set of equations supports the lattice temperature modulation behaviour obtained in the simulations and reveals that in-depth diffusion length is a determining parameter in the dispersion relation of unstable modes. Finally it is discussed how the change in optical properties can intensify the modulation-related effects.
Complex Observation in Electron Microscopy VIII: Novel Hilbert Phase-plates to Maximize Phase-contrast Sensitivity
Creators: name: Nagayama, Kuniaki
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Phase-plate transmission electron microscopy has recently regressed since a report that Volta phase-plate phase-contrast is less sensitive than non-phase-plate phase contrast, which leads to conventional defocusing phase-contrast. What about Hilbert phase-plate phase-contrast? We report that the Hilbert phase-plate method can survive if two experiments using a pair of symmetric Hilbert phase-plates, of which phase is set to a value smaller than π, are combined. Three phase-contrast methods using the symmetric Hilbert phase-plates and Zernike phase-plate representing Volta phase-plate and Scherzer defocus respectively were compared in sensitivity theoretically relying on a contrast transfer theory and computationally on a simulator specifically designed for phase plate transmission electron microscopy. For the two phase-plate phase-contrasts, the phase that gives the highest sensitivity was searched for by changing the phase-plate phase. As a result, the symmetric Hilbert phase-plates phase-contrast was found to outperform Scherzer defocus phase-contrast in the phase around π/2. On the other hand, Zernike phase-plate phase-contrast was found considerably inferior to Scherzer defocus phase-contrast in the entire phase range from 0 to π. Furthermore, the novel Hilbert phase-plate method was compared with complex observation transmission electron microscopy, which also requires two experiments, and the origin of the higher sensitivity of symmetric Hilbert phase-plates phase-contrast was examined.
description: 32 pages, 6 figures. Prepared for submission to JPSJ
Indien – globale Supermacht im 21. Jahrhundert?
Creators: name: Basting, Bernd
Publisher: name: Südasien
Year: 2022

description: Das 21. Jahrhundert wird eine Periode radikaler Veränderungen auf unserem Planeten sein. Die Welt wird nicht nur einen spürbaren Wandel des Weltklimas erleben, sondern auch der Weltgesellschaft und der globalen politischen und ökonomischen Machtstrukturen. Im letzteren Kontext beobachten wir schon jetzt die Metamorphose der lange bipolaren in eine multipolare Weltordnung, nach einer kurzen Phase der von den USA dominierten Unipolarität. Bislang ungeahnte Konstellationen entstehen, neue Allianzen und Antagonismen und: neue Supermächte, die die Zukunft der Erde entscheidend mitprägen werden. Diese werden Staaten vor allem der Südhalbkugel sein, die bis dato eher plastische Synonyme für Armut, Unterentwicklung, Misswirtschaft, Diktatur, staatliches und gesellschaftliches Chaos kurz: für weltpolitisch marginale Größen darstellten, die sich aber heute angesichts hoher ökonomischer Wachstumsraten, gesellschaftlicher Modernisierung und/oder politischer Demokratisierung zu einflussreichen Akteuren auf der Weltbühne transformiert haben. Zu nennen sind u.a. Brasilien, Südafrika, China und Indien.
description: Südasien, Bd. 30 Nr. 1 (2010): Ist eine andere Welt noch möglich? - Globalisierung aus indischer Perspektive
Symmetry in neutrino oscillation in matter with non-unitarity
Creators: name: Minakata, Hisakazu
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Recently we have developed a method called ``Symmetry Finder'' (SF) for hunting the reparametrization symmetry in the three-neutrino system in matter. Here, we apply SF to the Denton {\it et al.} (DMP) perturbation theory extended by including unitarity violation (UV), a possible low-energy manifestation of physics beyond the $ν$SM. Implementation of UV into the SF framework yields the additional two very different constraints, which nonetheless allow remarkably consistent solutions, the eight DMP-UV symmetries. Treatment of one of the constraints, the genuine non-unitary part, leads to the key identity which entails the UV $α$ parameter transformation only by rephasing, which innovates the invariance proof of the Hamiltonian. The quantum mechanical nature of the symmetry dictates the both $ν$SM and UV variables to transform jointly, through which the response of the two sectors are related to reveal their interplay. Thus, the symmetry can serve for a tool for diagnostics, probing the interrelation between the $ν$SM and a low-energy description of new physics. Problem of SF symmetry in vacuum is revisited to complete eight symmetries akin to DMP's.
description: Quantum nature of the Rep symmetry and completed vacuum SF symmetry added, version published in Acta Physica Polonica B
Interview mit Haznain Kazim
Creators: name: Redaktion, Die
Publisher: name: Südasien
Year: 2022

description: Hasnain Kazim wurde 1974 im niedersächsischen Oldenburg geboren und wuchs in dem Dorf Hollern-Twielenfleth im Alten Land, vor den Toren Hamburgs, sowie in Karatschi, Pakistan, auf. Er studierte Politikwissenschaft und schrieb unter anderem für die Heilbronner Stimme und die Nachrichtenagentur dpa. Ab 2006 war er Redakteur von SPIEGEL ONLINE, seit Juli 2009 ist er Südasienkorrespondent von SPIEGEL ONLINE und SPIEGEL. Kürzlich erschien sein Buch Grünkohl und Curry im Deutschen Taschenbuch Verlag.
description: Südasien, Bd. 30 Nr. 1 (2010): Ist eine andere Welt noch möglich? - Globalisierung aus indischer Perspektive
Farben des südasiatischen Theaters
Creators: name: Krüskemper, Elena
Publisher: name: Südasien
Year: 2022

description: Jedes Jahr im Januar veranstaltet die National School of Drama in Delhi ein Theaterfestival mit zahlreichen Aufführungen aus dem südasiatischen Raum und einigen westlichen Beiträgen. Das Programm bietet einen umfassenden Einblick in das kulturelle Schaffen des Subkontinents und spiegelt die Themen wieder, die die Künstler momentan beschäftigen.
description: Südasien, Bd. 30 Nr. 1 (2010): Ist eine andere Welt noch möglich? - Globalisierung aus indischer Perspektive
Constructing perturbation theory kernels for large-scale structure in generalized cosmologies
Creators: name: Taruya, Atsushi
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present a simple numerical scheme for perturbation theory (PT) calculations of large-scale structure. Solving the evolution equations for perturbations numerically, we construct the PT kernels as building blocks of statistical calculations, from which the power spectrum and/or correlation function can be systematically computed. The scheme is especially applicable to the generalized structure formation including modified gravity, in which the analytic construction of PT kernels is intractable. As an illustration, we show several examples for power spectrum calculations in $f(R)$ gravity and $Λ$CDM models.
description: 11 pages, 3 figures
Submicrometer tomographic resolution examined using a micro-fabricated test object
Creators: name: Mizutani, Ryuta
name: Takeuchi, Akihisa
name: Osamura, R. Yoshiyuki
name: Takekoshi, Susumu
name: Uesugi, Kentaro
name: Suzuki, Yoshio
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: To estimate the spatial resolution of microtomographs, a test object on the submicrometer scale was prepared by focused ion beam milling and subjected to microtomographic analysis. Since human tissues are composed of cells and extracellular matrices with micrometer and submicrometer structures, it is important to investigate the three-dimensional spatial resolution of microtomographs used to visualize microstructures of human tissues. The resolutions along the direction within the tomographic slice plane (in-plane resolution) and perpendicular to it (through-plane resolution) were determined from the modulation transfer function of square-wave patterns. The in-plane resolution was estimated to be 1.2 um from the modulation transfer function of the non-zoom image. In contrast, the zoom image gave the in-plane resolution of 0.8 um. This in-plane resolution is comparable to the through-plane resolution, which was estimated to be 0.8 um. Although the two-dimensional radiographs were taken with the pixel width of half the x-ray optics resolution, these three-dimensional resolution analyses indicated that the zoom reconstruction should be performed to achieve the in-plane resolution comparable to the x-ray optics resolution. The submicrometer three-dimensional analysis was applied in the structural study of human cerebral tissue stained with high-Z elements and the obtained tomograms revealed that the microtomographic analysis allows visualization of the subcellular structures of the cerebral tissue.
description: 13 pages, 4 figures
The Young and the Wild: What happens to Protoclusters forming at z = 4?
Creators: name: Remus, Rhea-Silvia
name: Dolag, Klaus
name: Dannerbauer, Helmut
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Using one of the largest volumes of the hydrodynamical cosmological simulation suit Magneticum, we study the evolution of protoclusters identified at redshift = 4, with properties similar to SPT2349-56. We identify 42 protoclusters in the simulation, as massive and equally rich in substructures as observed, confirming that these structures are already virialized. The dynamics of the internally fast rotating member galaxies within these protoclusters resembles observations, merging rapidly to form the cores of the BCGs of the assembling clusters. Half of the gas reservoir of these structures is in a hot phase, with the metal-enrichment at a very early stage. These systems show a good agreement with the observed amount of cold star-forming gas, largely enriched to solar values. We predict that some of the member galaxies are already quenched at z = 4, rendering them undetectable through measurements of their gas reservoir. Tracing the evolution of protoclusters reveals that none of the typical mass indicators at high redshift are good tracers to predict the present-day mass of the system. We find that none of the simulated protoclusters with properties as SPT2349-56 at z = 4.3, are among the top ten most massive clusters at redshift z = 0, with some barely reaching masses of M = 2 x 10^14Msun. Although the average star-formation and mass-growth rates in the simulated galaxies match observations at high redshift reasonably well, the simulation fails to reproduce the extremely high total star-formation rates within observed protoclusters, indicating that the sub-grid models are lacking the ability to reproduce higher star-formation efficiency (or lower depletion timescales).
description: 20 pages, 15 figures. Submitted to ApJ
A new anti-inflammatory thujane monoterpenoid glycoside ester from Pittosporum heterophyllum Franch
Creators: name: Ding, Jia-Qi
name: Guan, Sheng-Nan
name: Zhang, Yu-Feng
name: Wang, Zhao-Xuan
name: Kong, Wei-Zhen
name: Ren, Jun-Rui
name: Zhang, Xiu-Yun
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Biochemistry
subject: Microbiology
subject: FOS: Biological sciences
subject: Pharmacology
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: Immunology
subject: FOS: Clinical medicine
subject: Biological Sciences not elsewhere classified
subject: Inorganic Chemistry
subject: FOS: Chemical sciences
subject: Hematology

description: Phytochemical investigation of EtOH extract of Pittosporum heterophyllum led to one new esterified thujane monoterpenoid glycoside, pitheteroside A (1), together with one eudesmane sesquiterpenoid (2) and twelve lignans (3－14). Their structures were elucidated by extensive spectroscopic analysis, including 1D and 2D NMR, ECD calculation and HRESIMS spectra. Pitheteroside A is an unreported and highly esterified monoterpenoid glycoside. All isolates were evaluated for their nitric oxide production inhibition against LPS-induced BV-2 microglial cells. Among them, compounds 1, 6 and 8 showed significant activities with IC50 values less than 10 μM. The results indicated the metabolisms from P. heterophyllum possess potential anti-inflammatory effects.
Von der Erde Khoshals stieg ich als Melodie auf
Creators: name: Saber, Nasim
Publisher: name: Südasien
Year: 2022

description: Ajmal Khattak war eine Legende: Der Politiker, Journalist und Schriftsteller war langjähriger Chefredakteur der Zeitungen Bang-e haram und Anjam und Mitglied des Vorstands der Awami National Party (ANP) in Pakistan. Khattak vertrat seine Partei in der Nationalversammlung Pakistans und war zudem Mitglied im Pakistan Oppressed Nations Movement (PONM). Am 7. Februar ging sein von der Sache der Paschtunen erfülltes Leben zuende.
description: Südasien, Bd. 30 Nr. 1 (2010): Ist eine andere Welt noch möglich? - Globalisierung aus indischer Perspektive
Large-time asymptotics to the focusing nonlocal modified Kortweg-de Vries equation with step-like boundary conditions
Creators: name: Xu, Taiyang
name: Fan, Engui
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 35P25, 37K15, 35A01, 35Q51, 35Q55, 35Q15, 35G25

description: We investigate the large-time asymptotics of solution for the Cauchy problem of the nonlocal focusing modified Kortweg-de Vries (MKdV) equation with step-like initial data, i.e., $u_0(x)\rightarrow 0$ as $x\rightarrow-\infty$, $u_0(x)\rightarrow A$ as $x\rightarrow+\infty$,where $A$ is an arbitrary positive real number. We firstly develop the direct scattering theory to establish the basic Riemann-Hilbert (RH) problem associated with step-like initial data. Thanks to the symmetries $x\rightarrow-x$, $t\rightarrow-t$ of nonlocal MKdV equation, we investigate the asymptotics for $t\rightarrow-\infty$ and $t\rightarrow+\infty$ respectively. Our main technique is to use the steepest descent analysis to deform the original matrix-valued RH problem to corresponded regular RH problem, which could be explicitly solved. Finally we obtain the different large-time asymptotic behaviors of the solution of the Cauchy problem for focusing nonlocal MKdV equation in different space-time sectors $\mathcal{R}_{I}$, $\mathcal{R}_{II}$, $\mathcal{R}_{III}$ and $\mathcal{R}_{IV}$ on the whole $(x,t)$-plane.
description: 44 pages
Uncertainty-Aware Blob Detection with an Application to Integrated-Light Stellar Population Recoveries
Creators: name: Parzer, Fabian
name: Jethwa, Prashin
name: Boecker, Alina
name: Alfaro-Cuello, Mayte
name: Scherzer, Otmar
name: van de Ven, Glenn
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Numerical Analysis (math.NA)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Context. Blob detection is a common problem in astronomy. One example is in stellar population modelling, where the distribution of stellar ages and metallicities in a galaxy is inferred from observations. In this context, blobs may correspond to stars born in-situ versus those accreted from satellites, and the task of blob detection is to disentangle these components. A difficulty arises when the distributions come with significant uncertainties, as is the case for stellar population recoveries inferred from modelling spectra of unresolved stellar systems. There is currently no satisfactory method for blob detection with uncertainties. Aims. We introduce a method for uncertainty-aware blob detection developed in the context of stellar population modelling of integrated-light spectra of stellar systems. Methods. We develop theory and computational tools for an uncertainty-aware version of the classic Laplacian-of-Gaussians method for blob detection, which we call ULoG. This identifies significant blobs considering a variety of scales. As a prerequisite to apply ULoG to stellar population modelling, we introduce a method for efficient computation of uncertainties for spectral modelling. This method is based on the truncated Singular Value Decomposition and Markov Chain Monte Carlo sampling (SVD-MCMC). Results. We apply the methods to data of the star cluster M54. We show that the SVD-MCMC inferences match those from standard MCMC, but are a factor 5-10 faster to compute. We apply ULoG to the inferred M54 age/metallicity distributions, identifying between 2 or 3 significant, distinct populations amongst its stars.
description: Revision submitted to A&A, comments welcome
Precise late-time asymptotics of scalar field in the interior of a subextreme Kerr black hole and its application in Strong Cosmic Censorship conjecture
Creators: name: Ma, Siyuan
name: Zhang, Lin
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Analysis of PDEs (math.AP)
subject: FOS: Physical sciences
subject: FOS: Mathematics
subject: 35Q75, 58J37, 58J45, 58K55, 83C57, 83C75

description: In this work, we compute the precise late-time asymptotics for the scalar field in the interior of a non-static subextreme Kerr black hole, based on recent progress on deriving its precise asymptotics in the Kerr exterior region. This provides a new proof of the generic $H^1_{\text{loc}}$-inextendibility of the Kerr Cauchy horizon against scalar perturbations that is first shown by Luk--Sbierski (J. Func. Anal., 2016). The analogous results in Reissner--Nordström spacetimes are also discussed.
description: Compatible with the version that will appear in Transaction of the AMS
Predictive uncertainty on improved astrophysics recovery from multifield cosmology
Creators: name: Andrianomena, Sambatra
name: Hassan, Sultan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We investigate how the constraints on cosmological and astrophysical parameters ($Ω_{\rm m}$, $σ_{8}$, $A_{\rm SN1}$, $A_{\rm SN2}$) vary when exploiting information from multiple fields in cosmology. We make use of a convolutional neural network to retrieve the salient features from different combinations of field maps from IllustrisTNG in the CAMELS project. The fields considered are neutral hydrogen (HI), gas density (Mgas), magnetic fields (B) and gas metallicity (Z). We estimate the predictive uncertainty on the predictions of our model by using Monte Carlo dropout, a Bayesian approximation. Results show that overall, the performance of the model improves on all parameters as the number of channels of its input is increased. As compared to previous works, our model is able to predict the astrophysical parameters with up to $5\%$ higher in accuracy. In the best setup which includes all fields (four channel input, Mgas-HI-B-Z) the model achieves $R^{2} > 0.96$ on all parameters. Similarly, we find that the total uncertainty, which is dominated by the aleatoric uncertainty, decreases as more fields are used to train the model in general. The uncertainties obtained by dropout variational inference are overestimated on all parameters in our case, in that the predictive uncertainty is much larger than the actual squared error. After calibration, which consists of a simple $σ$ scaling method, the average deviation of the total uncertainty from the actual error goes down to $25\%$ at most (on $A_{\rm SN1}$).
description: 18 pages, 6 figures, 6 tables
Using game design to get better data in citizen science
Creators: name: Evans, Lisa
Publisher: name: Zenodo
Year: 2019

description: View a video of this presentation on YouTube here

Talk: Using Games Design in Citizen Science

Speaker: Lisa Evans

Most games are designed to be entertaining so they can drive sales or build a big community of players. For the astronomy citizen science project AstroQuest, we care about how much data we get, whether it's usable by our scientists, and whether we meet our goals for astronomy outreach and education. Lisa will talk about the design of the AstroQuest website and the process the team went through in using game design ideas to encourage citizen scientists to produce more and better data, as well as targeting their efforts where the scientists needed them the most.

Game Connect Asia Pacific 2019: Lighting The Way

Game Connect Asia Pacific is Australia's premier games development conference and a part of Melbourne International Games Week. Situated in Melbourne, Australia during October, GCAP is world-renowned for its talks, collaboration, expression, networking and inclusive environment.

Video courtesy of GCAP and the Game Developers' Association of Australia.

www.gcap.com.au
Atomistic structure search using local surrogate mode
Creators: name: Rønne, Nikolaj
name: Christiansen, Mads-Peter V.
name: Slavensky, Andreas Møller
name: Tang, Zeyuan
name: Brix, Florian
name: Pedersen, Mikkel Elkjær
name: Bisbo, Malthe Kjær
name: Hammer, Bjørk
Publisher: name: arXiv
Year: 2022
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Machine Learning (cs.LG)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: We describe a local surrogate model for use in conjunction with global structure search methods. The model follows the Gaussian approximation potential (GAP) formalism and is based on a the smooth overlap of atomic positions descriptor with sparsification in terms of a reduced number of local environments using mini-batch $k$-means. The model is implemented in the Atomistic Global Optimization X framework and used as a partial replacement of the local relaxations in basin hopping structure search. The approach is shown to be robust for a wide range of atomistic system including molecules, nano-particles, surface supported clusters and surface thin films. The benefits in a structure search context of a local surrogate model are demonstrated. This includes the ability to transfer learning from smaller systems as well as the possibility to perform concurrent multi-stoichiometry searches.
description: 12 pages, 11 figures
Cross-Camera Trajectories Help Person Retrieval in a Camera Network
Creators: name: Zhang, Xin
name: Xie, Xiaohua
name: Lai, Jianhuang
name: Zheng, Wei-Shi
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: We are concerned with retrieving a query person from multiple videos captured by a non-overlapping camera network. Existing methods often rely on purely visual matching or consider temporal constraints but ignore the spatial information of the camera network. To address this issue, we propose a pedestrian retrieval framework based on cross-camera trajectory generation, which integrates both temporal and spatial information. To obtain pedestrian trajectories, we propose a novel cross-camera spatio-temporal model that integrates pedestrians' walking habits and the path layout between cameras to form a joint probability distribution. Such a spatio-temporal model among a camera network can be specified using sparsely sampled pedestrian data. Based on the spatio-temporal model, cross-camera trajectories can be extracted by the conditional random field model and further optimized by restricted non-negative matrix factorization. Finally, a trajectory re-ranking technique is proposed to improve the pedestrian retrieval results. To verify the effectiveness of our method, we construct the first cross-camera pedestrian trajectory dataset, the Person Trajectory Dataset, in real surveillance scenarios. Extensive experiments verify the effectiveness and robustness of the proposed method.
description: IEEE Transactions on Image Processing (TIP), 2023
Data-driven reduced order models using invariant foliations, manifolds and autoencoders
Creators: name: Szalai, Robert
Publisher: name: arXiv
Year: 2022
Subjects: subject: Dynamical Systems (math.DS)
subject: Machine Learning (cs.LG)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences
subject: G.1.2; G.1.7; I.3.5
subject: 37M10, 37M21, 37C86, 68T09

description: This paper explores how to identify a reduced order model (ROM) from a physical system. A ROM captures an invariant subset of the observed dynamics. We find that there are four ways a physical system can be related to a mathematical model: invariant foliations, invariant manifolds, autoencoders and equation-free models. Identification of invariant manifolds and equation-free models require closed-loop manipulation of the system. Invariant foliations and autoencoders can also use off-line data. Only invariant foliations and invariant manifolds can identify ROMs, the rest identify complete models. Therefore, the common case of identifying a ROM from existing data can only be achieved using invariant foliations. Finding an invariant foliation requires approximating high-dimensional functions. For function approximation, we use polynomials with compressed tensor coefficients, whose complexity increases linearly with increasing dimensions. An invariant manifold can also be found as the fixed leaf of a foliation. This only requires us to resolve the foliation in a small neighbourhood of the invariant manifold, which greatly simplifies the process. Combining an invariant foliation with the corresponding invariant manifold provides an accurate ROM. We analyse the ROM in case of a focus type equilibrium, typical in mechanical systems. The nonlinear coordinate system defined by the invariant foliation or the invariant manifold distorts instantaneous frequencies and damping ratios, which we correct. Through examples we illustrate the calculation of invariant foliations and manifolds, and at the same time show that Koopman eigenfunctions and autoencoders fail to capture accurate ROMs under the same conditions.
description: 48 pages, 16 figures. Update: some bugs were fixed in the numerical calculations
Το απόρρητο της επικοινωνίας και οι προϋποθέσεις άρσης του για τη διακρίβωση εγκλημάτων
Creators: name: Τσάτσου, Φωτεινή Αποστόλου
Publisher: name: Aristotle University of Thessaloniki
Year: 2025
Subjects: Απόρρητο της Επικοινωνίας
Άρση Απορρήτου
Διακρίβωση Εγκλημάτων
Privacy of communiacation
Privacy removal
Criminal investigation

description: Θέμα της παρούσας εργασίας είναι ο τρόπος που το απόρρητο των επικοινωνιών προστατεύεται διαχρονικά στην Ελλάδα. Πρόκειται για μία σύντομη βιβλιογραφική ανασκόπηση του συνταγματικά κατοχυρωμένου στο άρθρο 19 του Συντάγματος δικαιώματος του απορρήτου των επικοινωνιών και στην ιδιαίτερη σπουδαιότητα που αποδίδει σ’ αυτό ο συνταγματικός νομοθέτης. Στην παρούσα εργασία θα αναλυθούν οι λόγοι που καθιστούν επιβεβλημένη ανάγκη την άρση του απορρήτου των επικοινωνιών για θέματα εθνικής ασφάλειας, αλλά και για την διακρίβωση ιδιαίτερα σοβαρών εγκλημάτων, υπό τους αυστηρούς όρους και περιορισμούς που τίθενται από τις ειδικότερες διατάξεις. Θα γίνει μία προσέγγιση των πολυσύνθετων ζητημάτων που ανακύπτουν από την άρση του απορρήτου των επικοινωνιών, ενώ θα γίνει αναφορά στην δικονομική αξιοποίηση των ευρημάτων και στην χρήση των αποδεικτικών μέσων που αποκτήθηκαν κατά παράβαση του απορρήτου των επικοινωνιών από τα Δικαστήρια. Παρατίθεται επίσης ενδεικτική σχετική νομολογία.
description: The subject of this paper is the way in which the confidentiality of communications has been protected over time in Greece. It is a brief bibliographic review of the constitutionally guaranteed right to the confidentiality of communications in article 19 of the Constitution and the particular importance that the constitutional legislator attributes to it. This paper will analyze the reasons that make it imperative to lift the secrecy of communications for national security issues, but also for the detection of particularly serious crimes, under the strict conditions and restrictions set by the more specific provisions. An approach will be made to the complex issues arising from the lifting of the confidentiality of communications, while reference will be made to the procedural exploitation of the findings and the use of evidence obtained in violation of the confidentiality of communications by the Courts. Indicative relevant case law is also provided.
description: Τμήμα Νομικής, Συνεργαζόμενα Τμήματα: Δημοσιογραφίας και Μέσων Μαζικής Επικοινωνίας
The electromagnetic decays of $X(3823)$ as the $ψ_2(1^{3}D_{2})$ state and its radial excited states
Creators: name: Li, Wei
name: Pei, Su-Yan
name: Wang, Tianhong
name: Wang, Ying-Long
name: Feng, Tai-Fu
name: Wang, Guo-Li
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We study the electromagnetic (EM) decays of $X(3823)$ as the $ψ_2(1^{3}D_{2})$ state by using the relativistic Bethe-Salpeter method. Our results are $Γ[X(3823)\rightarrowχ_{_{c0}}γ]=1.2$ keV, $Γ[X(3823)\rightarrowχ_{_{c1}}γ]=265$ keV, $Γ[X(3823)\rightarrowχ_{_{c2}}γ]=57$ keV and $Γ[X(3823)\rightarrowη_{_c}γ]=1.3$ keV. The ratio ${\cal B}[X(3823)\rightarrowχ_{_{c2}}γ]/{\cal B}[X(3823)\rightarrowχ_{_{c1}}γ]=0.22$, agrees with the experimental data. Similarly, the EM decay widths of $ψ_{_2}(n^{3}D_{_2})$, $n=2,3$, are predicted, and we find the dominant decays channels are $ψ_{_2}(n^{3}D_{_2})\rightarrowχ_{_{c1}}(nP)γ$, where $n=1,2,3$. The wave function include different partial waves, which means the relativistic effects are considered. We also study the contributions of different partial waves.
description: 35 pages, 7 figures, 9 tables
Scaling laws for electron kinetic effects in tokamak scrape-off layer plasmas
Creators: name: Power, Dominic
name: Mijin, Stefan
name: Wigram, Michael
name: Militello, Fulvio
name: Kingham, Robert J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Tokamak edge (scrape-off layer) plasmas can exhibit non-local transport in the direction parallel to the magnetic field due to steep temperature gradients. This effect along with its consequences has been explored at equilibrium for a range of conditions, from sheath-limited to detached, using the 1D kinetic electron code SOL-KiT, where the electrons are treated kinetically and compared to a self-consistent fluid model. Line-averaged suppression of the kinetic heat flux (compared to Spitzer-Harm) of up to 50% is observed, contrasting with up to 98% enhancement of the sheath heat transmission coefficient, $γ_e$. Simple scaling laws in terms of basic SOL parameters for both effects are presented. By implementing these scalings as corrections to the fluid model, we find good agreement with the kinetic model for target electron temperatures. It is found that the strongest kinetic effects in $γ_e$ are observed at low-intermediate collisionalities, and tend to increase at increasing upstream densities and temperatures. On the other hand, the heat flux suppression is found to increase monotonically as upstream collisionality decreases. The conditions simulated encompass collisionalities relevant to current and future tokamaks.
description: 24 pages, 14 figures
13C Isotopic Fractionation of HC3N in Star-Forming Regions -Low-Mass Star Forming Region L1527 and High-Mass Star Forming Region G28.28-0.36-
Creators: name: Taniguchi, Kotomi
name: Saito, Masao
name: Ozeki, Hiroyuki
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We observed the J=9-8 and 10-9 rotational lines of three13C isotopologues of HC3N in L1527 and G28.28-0.36 with the 45-m radio telescope of the Nobeyama Radio Observatory in order to constrain the main formation mechanisms of HC3N in each source. The abundance ratios of the three 13C isotopologues of HC3N are found to be 0.9 (0.2) : 1.00 : 1.29 (0.19) (1sigma) and 1.0 (0.2) : 1.00 : 1.47 (0.17) (1sigma) for [H13CCCN]: [HC13CCN]: [HCC13CN] in L1527 and G28.28-0.36, respectively. We recognize a similar 13C isotopic fractionation pattern that the abundances of H13CCCN and HC13CCN are comparable, and HCC13CN is more abundant than the others. Based on the results, we discuss the main formation pathway of HC3N. The 13C isotopic fractionation pattern derived from our observations can be explained by the neutral-neutral reaction between C2H2 and CN in both the low-mass (L1527) and high-mass (28.28-0.36) star forming regions.
description: Accepted for publication in ApJ, 10pages, 2 figures, 5 tables
A tale of 2-groups: D$_p$(USp(2N)) theories
Creators: name: Carta, Federico
name: Giacomelli, Simone
name: Mekareeya, Noppadol
name: Mininno, Alessandro
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: A 1-form symmetry and a 0-form symmetry may combine to form an extension known as the 2-group symmetry. We find the presence of the latter in a class of Argyres-Douglas theories, called $D_p($USp$(2N))$, which can be realized by $\mathbb{Z}_2$-twisted compactification of the 6d $\mathcal{N}=(2,0)$ of the $D$-type on a sphere with an irregular twisted puncture and a regular twisted full puncture. We propose the $3$d mirror theories of general $D_p($USp$(2N))$ theories that serve as an important tool to study their flavor symmetry and Higgs branch. Yet another important result is presented: We elucidate a technique, dubbed ''bootstrap'', which generates an infinite family of $D^b_p(G)$ theories, where for a given arbitrary group $G$ and a parameter $b$, each theory in the same family has the same number of mass parameters, same number of marginal deformations, same $1$-form symmetry, and same $2$-group structure. This technique is utilized to establish the presence or absence of the 2-group symmetries in several classes of $D^b_p(G)$ theories. In this regard, we find that the $D_p($USp$(2N))$ theories constitute a special class of Argyres-Douglas theories that have a 2-group symmetry.
description: v3: improved discussion and JHEP accepted, 32 pages + 2 appendices
Suppressing transverse mode instability through multimode excitation in a fiber amplifier
Creators: name: Chen, Chun-Wei
name: Wisal, Kabish
name: Eliezer, Yaniv
name: Stone, A. Douglas
name: Cao, Hui
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: High-power fiber laser amplifiers have enabled an increasing range of applications in industry, medicine and defense. The power scaling for narrow-band amplifiers is currently limited by the transverse modal instability. Various techniques have been developed to suppress the instability in a single or few-mode fiber in order to output a clean, collimated beam. Here we propose to use a highly multimode fiber and equal modal excitation to suppress the thermo-optical nonlinearity and instability. Our numerical simulations and theoretical analysis predict a significant reduction of dynamic coupling among the fiber modes with such excitation. When the bandwidth of a coherent seed is narrower than the spectral correlation width of the multimode fiber, the amplified light maintains high spatial coherence and can be transformed to any target pattern or focused to a diffraction-limited spot by a spatial mask at either input or output end of the amplifier. Our method simultaneously achieves high average power, narrow spectral width, and good beam quality, which are desired for fiber amplifiers in many applications.
title: Lymphocyte function in patients with certain neurological diseases
Creators: name: Menzies, Catherine B
Publisher: name: University of Glasgow
Year: 1980
Subjects: subject: Neurosciences
subject: FOS: Clinical medicine

description: The quantitative evaluation of the reactivity in human phytohaemagglutinin-stimulated lymphocyte cultures was studied using a whole blood technique. Cells were cultured for 22 hours in various concentrations of PHA, and by measuring the amount of incorporation of tritium labelled leucine into the proteins synthesised, a dose response curve could be drawn up for each donor. The patients studied fell into three main categories, (a) 22 patients with brain tumours. Depressed protein synthesis was detected in many of these when compared to 35 normal healthy controls, and also to 20 patients with various chronic neurological diseases. A 3-day culture technique was developed to test the effect of sera from patients with brain tumours, and other neurological complaints, on normal lymphocytes. No serum blocking factor was found. (b) Patients undergoing practolol therapy. Impaired T-cell function was seen in all patients whether they manifested adverse reactions to the drug in vivo or not. Normal lymphocytes were cultured for 2 days in the presence of various beta-blocking drugs, then their response to PHA was measured. Only propranolol was seen to cause depression of protein synthesis, (c) 31 patients with epilepsy who were taking various anticonvulsant drugs, including phenytoin. Low responses were seen in all patients on anticonvulsants when compared to 35 normal healthy controls.
Bacillus-supplemented diet improves growth performance in Jeju native pigs by modulating myogenesis and adipogenesis
Creators: name: Kim, Dahye
name: Min, Yunhui
name: Suminda, Godagama Gamaarachchige Dinesh
name: Hur, Chang-Gi
name: Lee, Sang-Chul
name: Lee, Hak-Kyo
name: Song, Ki-Duk
name: Heo, Jaeyoung
name: Son, Young-Ok
name: Lee, Dong-Sun
Publisher: name: Taylor & Francis
Year: 2022
Subjects: subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Biotechnology
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: Biological Sciences not elsewhere classified
subject: Developmental Biology

description: Probiotics are used in pigs as nutritional supplements to improve health and induce the development of muscle and adipose tissue for enhancing growth performance and harvesting quality meat. In this study, we investigated the effects of Bacillus-based probiotic supplementation on the physiological and biochemical changes in Jeju native pigs (JNPs), including growth performance, backfat layers, blood parameters, serum IgG levels, myogenic and adipogenic markers, and expression of inflammatory markers. Average daily gain and feed efficiency were higher in the Bacillus diet group than in the basal diet group, while backfat thickness was lower in the Bacillus diet group than in the basal diet group. Blood biochemical parameters and hematological profiles were not altered significantly by Bacillus-based probiotic supplementation. Serum IgG concentration increased in the Bacillus diet group compared to the basal diet group. The Bacillus diet group showed increased adipogenic and myogenic markers expression in the longissimus dorsi muscle and adipose tissues. Overall, the data suggest that the Bacillus-based probiotics-supplemented diet regulates myogenesis and adipogenesis in JNPs and improves growth performance. We postulate that this may be due to the changes in the gut microbiota of pigs due to probiotic supplementation.
Hybrid Information Flow Analysis for Programs with Arrays
Creators: name: Barany, Gergö
Publisher: name: arXiv
Year: 2016
Subjects: subject: Programming Languages (cs.PL)
subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences
subject: D.3.4; D.4.6

description: Information flow analysis checks whether certain pieces of (confidential) data may affect the results of computations in unwanted ways and thus leak information. Dynamic information flow analysis adds instrumentation code to the target software to track flows at run time and raise alarms if a flow policy is violated; hybrid analyses combine this with preliminary static analysis. Using a subset of C as the target language, we extend previous work on hybrid information flow analysis that handled pointers to scalars. Our extended formulation handles arrays, pointers to array elements, and pointer arithmetic. Information flow through arrays of pointers is tracked precisely while arrays of non-pointer types are summarized efficiently. A prototype of our approach is implemented using the Frama-C program analysis and transformation framework. Work on a full machine-checked proof of the correctness of our approach using Isabelle/HOL is well underway; we present the existing parts and sketch the rest of the correctness argument.
description: In Proceedings VPT 2016, arXiv:1607.01835
Towards 3D Face Reconstruction in Perspective Projection: Estimating 6DoF Face Pose from Monocular Image
Creators: name: Kao, Yueying
name: Pan, Bowen
name: Xu, Miao
name: Lyu, Jiangjing
name: Zhu, Xiangyu
name: Chang, Yuanzhang
name: Li, Xiaobo
name: Lei, Zhen
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: In 3D face reconstruction, orthogonal projection has been widely employed to substitute perspective projection to simplify the fitting process. This approximation performs well when the distance between camera and face is far enough. However, in some scenarios that the face is very close to camera or moving along the camera axis, the methods suffer from the inaccurate reconstruction and unstable temporal fitting due to the distortion under the perspective projection. In this paper, we aim to address the problem of single-image 3D face reconstruction under perspective projection. Specifically, a deep neural network, Perspective Network (PerspNet), is proposed to simultaneously reconstruct 3D face shape in canonical space and learn the correspondence between 2D pixels and 3D points, by which the 6DoF (6 Degrees of Freedom) face pose can be estimated to represent perspective projection. Besides, we contribute a large ARKitFace dataset to enable the training and evaluation of 3D face reconstruction solutions under the scenarios of perspective projection, which has 902,724 2D facial images with ground-truth 3D face mesh and annotated 6DoF pose parameters. Experimental results show that our approach outperforms current state-of-the-art methods by a significant margin. The code and data are available at https://github.com/cbsropenproject/6dof_face.
description: Accepted by TIP
LitePIG: A Lite Parameter Inference system for the Gravitational wave in the millihertz band
Creators: name: Wang, Renjie
name: Hu, Bin
Publisher: name: arXiv
Year: 2022
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We present a python based parameter inference system for the gravitational wave (GW) measured in the millihertz band. This system includes the following features: the GW waveform originated from the massive black hole binaries (MBHB), the stationary instrumental gaussian noise, the higher-order harmonic modes, the full response function from the time delay interferometry (TDI) and the gaussian likelihood function with the dynamic nested parameter sampler. In particular, we highlight the role of higher-order modes. By including these modes, the luminosity distance estimation precision can be improved roughly by a factor of 50, compared with the case with only the leading order ($\ell=2,|m|=2$) mode. This is due to the response function of different harmonic modes on the inclination angle are different. Hence, it can help to break the distance-inclination degeneracy. Furthermore, we show the robustness of testing general relativity (GR) by using the higher-order harmonics. Our results show that the GW from MBHB can simultaneously constrain four of the higher harmonic amplitudes (deviation from GR) with a precision of $c_{21}=0.54^{+0.61}_{-0.82}$, $c_{32}=-0.65^{+0.22}_{-0.08}$, $c_{33}=0.56^{+0.60}_{-0.76}$ and $c_{44}=1.57^{+2.34}_{-1.90}$, respectively.
description: 9 pages, 7 figures