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Maximizing revaccination effectiveness under resource constraints in the SIRVS model

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Physica A: Statistical Mechanics and its Applications 2025年 671卷

作者： Zbik, Bartosz Dybiec, Bartlomiej Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University ul. St. Lojasiewicza 11 Krakow30–348 Poland Institute of Theoretical Physics and Mark Kac Center for Complex Systems Research Jagiellonian University ul. St. Lojasiewicza 11 Krakow30–348 Poland

Discrete compartmental epidemiological models are widely used in epidemiological modeling because they allow the study of relationships between microscopic dynamics and macroscopic properties of the epidemic. They can also be used to optimize control strategies. Adequate planning of epidemic control methods is particularly important in situations where the disease may be endemic or where repeated vaccination is required due to new mutations or loss of immunity. Using the agent-based SIRVS model, we show that despite limited resources, it is still possible to design the most effective control strategy by finding the optimal time interval between successive booster doses. Importantly, the optimal time between successive vaccinations exists even in the presence of limited resources. Its value depends on the proportion of the population willing to take the vaccine and is also influenced by the clustering of individuals with respect to their attitudes toward vaccination. Finally, we show that from an individual perspective, willingness to vaccinate, coupled with successful vaccination, are key components in reducing the number of reinfections of the same individual. © 2025 Elsevier B.V.

关键词： Malaria control

Unique Properties of the Electronic Structure of Alluaudite Sodium Iron Sulfate Cathode Material and the Impact on its Electrochemical Performance

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SSRN

SSRN 2025年

作者： Molenda, Janina Tobola, Janusz Milewska, Anna Budziak, Andrzej Zając, Wojciech Wolczko, Marta Dziedzic-Kocurek, Katarzyna Nowak, Mikolaj Kalahurska, Katarzyna Imam, Neama Henkel, Karsten Flege, Jan Ingo Zschech, Ehrenfried Dresden University of Technology Germany AGH University of Krakow Faculty of Energy and Fuels Al. Mickiewicza 30 Krakow30-059 Poland AGH University of Krakow Faculty of Physics and Applied Computer Science Al. Mickiewicza 30 Krakow30-059 Poland Jagiellonian University Faculty of Physics Astronomy and Applied Computer Science ul. S. Lojasiewicza 11 Krakow30-348 Poland Brandenburg University of Technology Cottbus-Senftenberg Institute of Physics Konrad-Zuse-Str. 1 Cottbus03046 Germany

This work explores the unique properties of the electronic structure of alluaudite-type Na2.5Fe1.75(SO4)3, which impacts its electrochemical properties as a cathode for sodium-ion batteries (SIBs). Density functional theory calculations using the implemented KKR-CPA package (Korringa-Kohn-Rostoker method combined with the coherent potential approximation) showed the diverse electrochemical activity of sodium at different sites within the alluaudite structure. This revealed unprecedented contributions of the Na atoms to the overall electronic density of states near the Fermi energy (dominated by d-Fe and p-O states), undetected before in the group of layered transition oxide cathode materials. A high-purity Na2.5Fe1.75(SO4)3 cathode material was synthesized by optimizing the solid-state synthesis route. Based on a multi-technique approach including: X-ray diffraction, scanning electron microscopy, Mössbauer, X-ray photoelectron, Fourier Transform Infrared, and Raman spectroscopy studies, the electronic structure and electrochemical properties of the cathode material and its evolution during the sodium deintercalation/intercalation processes have been characterized, providing a comprehensive understanding of the sodium storage mechanism. Operando and in-situ X-ray diffraction studies monitored changes in the crystal structure of the cathode material during charge/discharge cycles showing that the system exhibits a reversible tendency to amorphize at deep sodium deintercalation. The electrochemical analysis showed reversible cycling with minimal capacity loss (only 2.5% after 300 cycles at discharge at C/5 current loading), demonstrating high structural stability of this optimized cathode material. © 2025, The Authors. All rights reserved.

关键词： Sodium-ion batteries

Kink movement on a periodic background

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Physical Review E 2025年第2期111卷 024203-024203页

作者： Tomasz Dobrowolski Jacek Gatlik Panayotis G. Kevrekidis Department of Computer Physics and Quantum Computing University of the National Education Commission in Krakow Podchorążych 2 30-084 Cracow Poland AGH University of Krakow Faculty of Physics and Applied Computer Science 30-059 Krakow Poland Department of Mathematics and Statistics University of Massachusetts Amherst Massachusetts 01003-4515 USA

The behavior of the kink in the sine-Gordon (sG) model in the presence of periodic inhomogeneity is studied. An ansatz is proposed that allows for the construction of a reliable effective model with two degrees of freedom. Effective models featuring very good agreement with the original field-theoretic partial differential equation are constructed, including in the nonperturbative region and for relativistic velocities. The numerical solutions of the sG model describing the evolution of the kink in the presence of a barrier as well as in the case of a periodic heterogeneity under the potential additional influence of a switched bias current and/or dissipation were obtained. The results of the field equation and the effective models were favorably compared. The effect of the choice of initial conditions in the field model on the agreement of the results with the effective model is also discussed.

关键词： sine-Gordon equation

Characterisation of Hβ spectra from EXO 051910+3737.7 X-rays binaries

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arXiv 2025年

作者： Nuchvanichakul, Pornisara Irawati, Puji Rittipruk, Pakakaew Gandhi, Poshak Knigge, Christian Charles, Phil Wannawichian, Suwicha M.S. Program in Applied Physics Department of Physics and Materials Science Faculty of Science Chiang Mai University Chiang Mai50200 Thailand Department of Physics and Astronomy University of Southampton Southampton United Kingdom National Astronomical Research Institute of Thailand Chiang Mai50180 Thailand Department of Physics and Materials Science Faculty of Science Chiang Mai University Chiang Mai50200 Thailand

We investigate the spectral characteristics of the Be/X-ray binary system, EXO 051910+3737.7, in which Be/X-ray systems are the largest sub-class of high-mass X-ray binaries. Spectroscopic observations are taken by the Thai National Telescope (TNT) with a Medium-RESolution spectrograph (MRES) instrument for seven nights spanning from 2020 to 2021. Our primary focus is directed towards the analysis of two Balmer lines, namely Hα and Hβ, given that Be stars typically exhibit emission features in at least one of these hydrogen Balmer lines during certain phases. Our observations reveal split Balmer emission lines throughout the entire duration of our monitoring. Double Gaussian profiles were employed for line fitting to characterize these lines. The presence of double peaks in the Balmer lines indicates the presence of asymmetries within the circumstellar disc. We then analyze V/R variations and the changes in Hβ spectra. Our analysis of V/R variation which Violet (V) and Red (R) peak intensity components, revealed rapid fluctuations occurring within a single day, although determining the precise periodicity was constrained by instrumental limitations and the duration of observability. Furthermore, employing observed the wavelength differences (∆λ) in conjunction with typical Be star parameters allowed us to estimate the radius (rβ) of the Hβ emitting envelope. The average value was calculated to be 2.585r∗, with a standard deviation of 0.050r∗ © 2025, CC BY-NC-ND.

关键词： Stars

Investigating the Redshift Evolution of Lensing Galaxy Density Slopes via Model-Independent Distance Ratios

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arXiv 2025年

作者： Geng, Shuaibo Grespan, Margherita Thuruthipilly, Hareesh Harikumar, Sreekanth Pollo, Agnieszka Biesiada, Marek National Centre for Nuclear Research ul. Pasteura 7 Warsaw02-093 Poland Astronomical Observatory of the Jagiellonian University Faculty of Physics Astronomy and Applied Computer Science ul. Orla 171 Kraków30-244 Poland

Context. Strong lensing systems, expected to be abundantly discovered by next-generation surveys, provide a powerful tool for studying cosmology and galaxy evolution. The coupling between galaxy structure and cosmology through distance ratios makes examining the evolution of lensing galaxy mass density profiles essential for advancing both fields. Aims. We introduce a novel, dark energy-model-independent method to investigate the mass density slopes of lensing galaxies and their redshift evolution using an extended power-law (EPL) model. Methods. We adopt a non-parametric approach based on Artificial Neural Networks (ANNs) trained on Type Ia Supernovae (SNIa) data to reconstruct the distance ratios of strong lensing systems. These reconstructed ratios are compared with theoretical predictions to estimate the evolution of EPL model parameters. The analysis is performed at three levels - combined sample, individual lenses, and binned groups - to ensure robust estimates of the EPL parameters. Results. A negative evolutionary trend of mass density power-law exponent with increasing redshift is observed across different analysis levels. Assuming a triangular prior for the anisotropy of lensing galaxies, we find evidence for redshift evolution of the mass density slope, quantified as ∂γ/∂z = −0.20 ± 0.12. Conclusions. This study confirms that the redshift evolution of matter density slopes in lensing galaxies can be determined independent of dark energy models at the population level. Using simulations informed by Legacy Survey of Space and Time (LSST) Rubin Observatory forecasts, which is expected to identify 100,000 strongly lensed galaxies, we show that spectroscopic follow up of just 10% of these systems can reduce the uncertainty in the redshift evolution coefficient of the total mass density slope (∆∂γ/∂z) to 0.021. Such precision would be able to distinguish between evolving and non-evolving pictures for lensing galaxies. © 2025, CC BY-NC-ND.

关键词： Dark energy

Synergistic eigenanalysis of covariance and Hessian matrices for enhanced binary classification on health datasets

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computers in Biology and Medicine 2025年 190卷 109985-109985页

作者： Hartoyo, Agus Argasiński, Jan Trenk, Aleksandra Przybylska, Kinga Blasiak, Anna Crimi, Alessandro Sano – Centre for Computational Personalised Medicine International Research Foundation Krakow Poland Department of Neurophysiology and Chronobiology Institute of Zoology and Biomedical Research Faculty of Biology Jagiellonian University Krakow Poland AGH University of Krakow Krakow Poland School of Computing Telkom University Bandung Indonesia Department of Human-Centered Artificial Intelligence Institute of Applied Computer Science Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University Krakow Poland Doctoral School of Exact and Natural Sciences Jagiellonian University Krakow Poland

Covariance and Hessian matrices have been analyzed separately in the literature for classification problems. However, integrating these matrices has the potential to enhance their combined power in improving classification performance. We present a novel approach that combines the eigenanalysis of a covariance matrix evaluated on a training set with a Hessian matrix evaluated on a deep learning model to achieve optimal class separability in binary classification tasks. Our approach is substantiated by formal proofs that establish its capability to maximize between-class mean distance (the concept of separation) and minimize within-class variances (the concept of compactness), which together define the two linear discriminant analysis (LDA) criteria, particularly under ideal data conditions such as isotropy around class means and dominant leading eigenvalues. By projecting data into the combined space of the most relevant eigendirections from both matrices, we achieve optimal class separability as per these LDA criteria. Empirical validation across neural and health datasets consistently supports our theoretical framework and demonstrates that our method outperforms established methods. Our method stands out by addressing both separation and compactness criteria, unlike PCA and the Hessian method, which predominantly emphasize one criterion each. This comprehensive approach captures intricate patterns and relationships, enhancing classification performance. Furthermore, through the utilization of both LDA criteria, our method outperforms LDA itself by leveraging higher-dimensional feature spaces, in accordance with Cover's theorem, which favors linear separability in higher dimensions. Additionally, our approach sheds light on complex DNN decision-making, rendering them comprehensible within a 2D space. © 2025

关键词： Covariance matrix

Cause or Trigger? From Philosophy to Causal Modeling

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arXiv 2025年

作者： Hlaváčková-Schindler, Kateřina Wöß, Rainer Pecorino, Vera Schindler, Philip Research Group Data Mining and Machine Learning Faculty of Computer Science University of Vienna Vienna Austria Department of Physics and Astronomy University of Catania Catania Italy Faculty of Philosophy University of Vienna Vienna Austria

Not much has been written about the role of triggers in the literature on causal reasoning, causal modeling, or philosophy. In this paper, we focus on describing triggers and causes in the metaphysical sense and on characterizations that differentiate them from each other. We carry out a philosophical analysis of these differences. From this, we formulate a definition that clearly differentiates triggers from causes and can be used for causal reasoning in natural sciences. We propose a mathematical model and the Cause- Trigger algorithm, which, based on given data to observable processes, is able to determine whether a process is a cause or a trigger of an effect. The possibility to distinguish triggers from causes directly from data makes the algorithm a useful tool in natural sciences using observational data, but also for real-world scenarios. For example, knowing the processes that trigger causes of a tropical storm could give politicians time to develop actions such as evacuation the population. Similarly, knowing the triggers of processes that cause global warming could help politicians focus on effective actions. We demonstrate our algorithm on the climatological data of two recent cyclones, Freddy and Zazu. The Cause-Trigger algorithm detects processes that trigger high wind speed in both storms during their cyclogenesis. The findings obtained agree with expert knowledge. © 2025, CC BY.

关键词： Physical properties

SELECTED ASPECTS OF PLANETARY physics

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Acta Physica Polonica B, Proceedings Supplement

Acta Physica Polonica B, Proceedings Supplement 2025年第3期18卷

作者： Kozakiewicz, J. Gurgurewicz, J. Mège, D. Olszewski, R. Blęcka, M.I. Choromański, K. Czechowski, L. Czernic, P. Frodyma, N. Orlanducci, C. Poppe, S. Tesson, P.-A. Zalewska, N. Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University Lojasiewicza 11 Kraków30-348 Poland Centrum Badań Kosmicznych Polskiej Akademii Nauk Bartycka 18A Warsaw00-716 Poland Faculty of Geodesy and Cartography Warsaw University of Technology pl. Politechniki 1 Warsaw00-661 Poland

We give an overview of Polish activities in planetary physics, based on contributions presented at the National Mars science Seminars and the Planetary science Conference held at the Jagiellonian University in Kraków since 2019. During the five editions of the conference, about 50 presentations were discussed showing how robust and important the role of the Polish scientific community in planetary science is. © 2025 Jagiellonian University. All rights reserved.

关键词： Astrophysics

Constraining the Gravitational Wave Speed in the Early Universe via Gravitational Cherenkov Radiation

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arXiv 2025年

作者： Delgado, Paola C.M. Ganz, Alexander Lin, Chunshan Thériault, Roxane CEICO FZU - Institute of Physics of the Czech Academy of Sciences Na Slovance 1999/2 Prague182 00 Czech Republic Institute for Theoretical Physics Leibniz University Hannover Appelstraße 2 Hannover30167 Germany Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University Krakow30-348 Poland

Scalar particles traveling faster than a subluminal gravitational wave generate gravitons via gravitational Cherenkov radiation. In this paper, we investigate graviton production by the primordial plasma within the framework of modified gravity in the early Universe, generating a relic graviton background. We find that for the minimal model, where only the speed of gravitational waves is modified and a standard model plasma minimally couples to gravity, the relic graviton background can be enhanced by several orders of magnitude, but still agrees with the Big Bang Nucleosynthesis (BBN) bound in most cases. Moreover, we also find that for Horndeski theories, such as Galileon theory, the relic background produced by the thermalized scalar field can reach significant amplitudes, exceeding the BBN bound for a region of the parameter space. By requiring the relic graviton background to remain consistent with the BBN constraint, we derive limits on the gravitational wave speed at early times in these modified gravity theories. Copyright © 2025, The Authors. All rights reserved.

关键词： Gravitational effects