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Simulating the differences in directional cardiorespiratory coupling in the awake state and different stages of sleep using a comprehensive mathematical model
European Physical Journal: Special Topics. 2024. Vol. 233. P. 569–577.
Ishbulatov Y., Kurbako A., Vahlaeva A., Prokhorov M., Gridnev V., Karavaev A., Penzel T.
We propose a mathematical model of the human cardiovascular and respiratory systems. The cardiovascular segment of the model simulates the main heart rate, oscillating blood pressure, peripheral vascular resistance, and nonlinear dynamics of the autonomic control of circulation, namely α- and βsympathetic and parasympathetic control. The respiratory part includes central pattern generator, lungs, and a control loop sensitive to the concentration of CO2 and O2 in the arterial blood. Both parts of the model are linked in a physiological manner. The adequacy of the model is demonstrated by comparing the simulated time series to the experimental records of healthy subjects from the SIESTA database using spectral analysis, statistical analysis, and nonlinear measures of directional coupling. The proposed model can become a useful tool for investigation of the cardiovascular dynamics during sleep.
Publication based on the results of:
Degtyarev A., Bakhurin S., Yudin N., DSPA 2026 P. 1–6
This paper investigates one possible solution to the problem of self-interference cancellation (SIC) arising in the design of in-band full-duplex (IBFD) communication systems. Self-interference cancellation is performed in the digital domain using multilayer nonlinear models adapted via gradient-based optimization. The presence of local minima and saddle points during the adaptation of multilayer models limits the ...
Added: May 26, 2026
Ilyashenko Y., Shilin I., Stanislav Minkov, Russian Journal of Mathematical Physics 2026 Vol. 33 No. 1 P. 89–106
In this paper, new numerical invariants of structurally unstable vector fields in the plane
are found. One of the main tools is an improved asymptotics of sparkling saddle connections that
occur when a separatrix loop of a hyperbolic saddle breaks. Another main tool is a new topological
invariant of two arithmetic progressions, both perturbed and unperturbed, on the ...
Added: May 26, 2026
Gusev I., Maksaev A., Promyslov V., Journal of Mathematical Sciences 2025 Vol. 299 No. 6
The regular graph of the space of n × m matrices over a field F is defined as the undirected graph whose vertices are matrices of rank min(n, m), and distinct matrices A and B are connected by an edge if and only if rk(A + B) < min(n, m). In this paper, for |F| ...
Added: May 25, 2026
Tyukin I., Tyukina T., van Helden D. P. et al., Information Sciences 2024 Vol. 678 Article 120856
AI errors pose a significant challenge, hindering real-world applications. This work introduces a novel approach to cope with AI errors using weakly supervised error correctors that guarantee a specific level of error reduction. Our correctors have low computational cost and can be used to decide whether to abstain from making an unsafe classification. We provide ...
Added: May 23, 2026
Zaikin A., Sviridov I., Sosedka A. et al., Technologies 2026 Vol. 14 No. 2 Article 84
High-dimensional tabular data are common in biomedical and clinical research, yet conventional machine learning methods often struggle in such settings due to data scarcity, feature redundancy, and limited generalization. In this study, we systematically evaluate Synolitic Graph Neural Networks (SGNNs), a framework that transforms high-dimensional samples into sample-specific graphs by training ensembles of low-dimensional pairwise ...
Added: May 23, 2026
Kibkalo Vladislav, Chertopolokhov V., Mukhamedov A. et al., IEEE Access 2026 Vol. 14 P. 14369–14392
This study presents on-the-fly identification and multi-step prediction of nonlinear systems with delayed inputs using a dynamic neural network combined with a smooth projection onto ellipsoids. The projection enforces parameter constraints that guarantee stability, while a Lyapunov–Krasovskii analysis yields computable ultimate error bounds. Riccati-type matrix inequalities are derived, providing an efficient vectorization–projection–devectorization implementation suitable for ...
Added: May 22, 2026
Морозов С. В., Calcolo 2026 Vol. 63 No. 2 Article 23
The approximation of tensors in a low-para metric format is a crucial component in many mathematical modelling and data analysis tasks. Among the widely used low-parametric representations, the canonical polyadic (CP) decomposition is known to be very efficient. Nowadays, most algorithms for CP approximation aim to construct the approximation in the Frobenius norm; however, some ...
Added: May 22, 2026
Селянин Ф. И., Journal of Dynamical and Control Systems 2026 Vol. 32 No. 2 Article 18
A B-facet is a lattice -dimensional polytope in the positive octant with a positive normal covector, such that every -dimensional simplex with vertices in it is a B-simplex (i.e., a pyramid of height one with base on a coordinate hyperplane). B-facets were introduced in [2] in the context of the monodromy conjecture. In this paper, we complete the ...
Added: May 21, 2026
Ausubel L., Baranov O., Journal of Economic Theory 2026 Vol. 235 No. 106192
The Vickrey-Clarke-Groves (VCG) mechanism is one of the most compelling constructs in mechanism design, but the presence of complementary goods creates the possibility of non-core and even zero-revenue outcomes. In this article, we show that joint feasibility constraints on allocations offer a second pathway to ill-behaved outcomes in the VCG mechanism, even when all bidders ...
Added: May 20, 2026
Denis Seliutskii, Russian Journal of Mathematical Physics 2025 Vol. 32 No. 2 P. 399–407
In this paper, we find an upper bound for the first Steklov eigenvalue for a surface of revolution with boundary consisting of two spheres of different radii. Moreover, we prove that, in some cases, this boundary is sharp. ...
Added: May 19, 2026
Жакупов О. Б., European Journal of Mathematics 2025 Vol. 11 Article 84
We provide examples of smooth three-dimensional Fano complete intersections of degree 2, 4, 6, and 8 that have absolute coregularity 0. Considering the main theorem of Avilov, Loginov, and Przyjalkowski (CNTP 18:506–577, 2024) on the remaining 101 families of smooth Fano threefolds, our result implies that each family of smooth Fano threefolds has an element of absolute ...
Added: May 18, 2026
Gurevich E., Saraev I., Известия РАН. Серия математическая 2026 Т. 90 № 3 С. 19–56
In this paper, we consider a class of gradient-like ows without heteroclinic
intersections, dened on closed manifolds of dimension four. We show that for
such ows, the problem of complete topological classication can be reduced to
the combinatorial problem of distinguishing special framed graphs describing
the mutual arrangement of invariant manifolds and the action of the ow on a
wandering ...
Added: May 18, 2026
Gonchenko S., Lerman L., Turaev D., Regular and Chaotic Dynamics 2026 Vol. 31 No. 3 P. 349–369
We show that bifurcations of four-dimensional symplectic diffeomorphisms with a quadratic homoclinic tangency to a saddle periodic orbit with real multipliers produce 2-elliptic periodic orbits if the tangency is not partially hyperbolic. We show that a normal form for the rescaled first-return maps near such tangency is given by a four-dimensional symplectic H´enonlike map and study bifurcations of the ...
Added: May 15, 2026
Aleskerov F. T., Khutorskaya O., Stepochkina A. et al., Springer, 2026.
The book contains new models of bibliometric analysis based on centrality measures in network analysis, pattern analysis and stability analysis. A distinctive feature of these centrality measures is that they account for the parameters of vertices and group influence of vertices to a vertex. This reveals specific groups of publications, authors, terms, journals and affiliations ...
Added: May 15, 2026
Kuptsov P., Panyushev A., Stankevich N., Chaos 2026 Vol. 36 No. 5 Article 053138
We develop a machine-learning approach to reproduce the behavior of two versions of the van der Pol oscillator exhibiting a subcritical Andronov–Hopf bifurcation, with or without a codimension-2 Bautin point. We construct a neural-network model that functions as a recur rent map and train it on short segments of oscillator trajectories. The results show that, ...
Added: May 15, 2026
Dorovskiy A., / Series arXiv "math". 2026.
In this paper the structural stability of generic families of vector fields of the PC-HC class on the two-dimensional sphere is proved. A classification of these families up to moderate equivalence in neighborhoods of their large bifurcation supports is presented, based on such invariants as the configuration and the characteristic set. The realization lemma is proved. ...
Added: May 14, 2026
Lebedev V., Journal of Mathematical Analysis and Applications 2026 Vol. 563 No. 2 Article 130787
It is known that for every continuous real-valued
function $f$ on the circle $\mathbb T=\mathbb R/2\pi\mathbb Z$ there exists a
change of variable, i.e., a self-homeomorphism $h$ of $\mathbb T$, such that
the superposition $f\circ h$ is in the Sobolev space $W_2^{1/2}(\mathbb T)$.
We obtain new results on simultaneous improvement of functions by a single
change of variable in relation ...
Added: May 14, 2026
Соловьева А. К., Исаев М. Р., Бобров П. Д. et al., Журнал высшей нервной деятельности им. И.П. Павлова 2025 Т. 75 № 6 С. 756–769
There is a need for empirical indicators that can monitor subtle changes in wakefulness levels with high temporal resolution. We aimed to assess the applicability in this regard of several indices based on the average spectral power of EEG rhythms, as well as the BIS index used in anesthesiology. 26 volunteers participated in an experiment involving forced awakenings ...
Added: March 6, 2026
Leonid Grinin, Markov A., Korotayev A., Journal of Big History 2025 Vol. 8 No. 3 P. 1–51
In this paper, Grinin et al. survey general similarities and differences between biological and social macroevolution and phases of Big History. The comparison of biological and social evolution is an important but (regrettably) understudied subject. The authors have endeavored to make a systematic comparison between biological and social evolution at different levels of analysis and ...
Added: November 1, 2025
Akhremenko A. S., Philippov I., Sychev V. et al., Политическая наука 2025 № 1 С. 77–102
Modern academic literature has focused on technology adaptation and innovation in politics and public administration. At present, there is a large number of studies, the central object of which is such an actively developing phenomenon as public digital services. Despite the diverse range of theoretical approaches, there is no established methodological tradition of modelling the ...
Added: May 1, 2025
Efremov Y., Ermolaeva A., Vladimirov G. et al., Plos One 2022 Vol. 17 No. 6
Cardiovascular diseases associated with high cholesterol (hypercholesterolemia) and low-density lipoproteins (LDL) levels are significant contributors to total mortality in developing and developed countries. Mathematical modeling of LDL metabolism is an important step in the development of drugs for hypercholesterolemia. The aim of this work was to develop and to analyze an integrated mathematical model of ...
Added: April 9, 2025
Лесин А. В., Исаев А. В., Тонконогов Б. П. et al., Тонкие химические технологии 2023 Т. 19 № 6 С. 485–496
Objectives. A quick cold start of emergency and auxiliary power units based on diesel engines should be possible at any time without
problems and in the shortest possible time. The condition of the engine oil is one of the most important factors influencing the smooth
start-up of power plants. During diesel engine operation, engine oil accumulates soot ...
Added: February 26, 2025
Gallo F., Myachykov A., Abutalebi J. et al., Brain and Language 2025 Vol. 260 Article 105507
Sleep and language are fundamental to human existence and have both been shown to substantially affect cognitive functioning including memory, attentional performance, and cognitive control. Surprisingly, there is little-to-no research that examines the shared impact of bilingualism and sleep on cognitive functions. In this paper, we provide a general overview of existing research on the ...
Added: February 21, 2025
Сизикова Т. Э., Леонов С. В., Polikanova I., Экспериментальная психология 2024 Т. 17 № 3 С. 168–184
The aim of this study was to test the hypothesis of the effectiveness and adequacy of using reflection to reduce anxiety levels in groups with high and low anxiety. There is evidence in the literature of a negative correlation between heart rate variability (HRV) and anxiety levels, as well as also evidence of the positive ...
Added: October 25, 2024