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Realistic vibration predictions of railway bridges during high-speed train crossings require reliable dynamic input parameters for the applied calculation model. In particular, the dynamic stiffness and damping properties of the ballast superstructure for the mathematical consideration of the vertical track–bridge interaction (TBI) significantly influence the generated calculation results. However, due to a striking scattering of model-related characteristic values available in the literature, adequate and realistic consideration of the dynamic properties of the vertical TBI in vibration predictions is associated with considerable uncertainties. This uncertainness illustrates the need to determine experimental-based and reliable characteristic values. For targeted and isolated research of dynamic characteristics of vertical TBI, a unique large-scale test facility was developed at the Institute of Structural Engineering at TU Wien, which replicates a section of ballast superstructure on a railway bridge on a scale of 1:1 and excited to vertical movements. This paper presents the essential results and findings from the experiments, focusing on determining the ballast superstructure’s dynamic stiffness and damping characteristics, which can subsequently be implemented in practical applications for vibration predictions. As a result of the experiments, model-related dynamic stiffness and damping parameters are provided to describe the vertical TBI. In addition, the experiments are used to identify destabilization processes occurring in the ballast superstructure as a result of vertical vibrations. The investigations include the vertical TBI’s displacement and acceleration behavior and the track’s settlement behavior due to the entire structure’s vertical movements. These investigations allow for assessing the currently valid, internationally, and nationally normatively prescribed permissible accelerations for railway bridges due to train crossings. The conclusion is that short-term excessive vertical accelerations of the ballast superstructure caused by train passage do not destabilize the ballast bed or considerably change the track position.

The synthesis and characterization of a series of 5-nitro-$N$-phenyl-3-(phenylamino)-1$H$-indazole-1-carboxamide 5-NPIC derivatives (5a– 5v) have been reported as anticancer agents in this study. These derivatives were synthesized by reacting 3-chloro-5-nitro-$N$-phenyl-1$H$-indazole-1-carboxamide (4) with a variety of aniline derivatives in isopropanol. FT-IR, ¹H-NMR, 13C-NMR and mass spectral methods were employed to confirm the structures of analogues (5a– 5v). The anticancer activity evaluation of compounds 5a– 5v revealed that 3-((3-methoxyphenyl) amino)-5-nitro-$N$-phenyl-1$H$-indazole-1-carboxamide (5j) exhibited good efficacy. The stability of ligand–protein complexes was systematically evaluated using molecular dynamics simulations (MDS), which demonstrated a consistent and robust binding of the most potent compound within the binding sites of target proteins. The results confirmed the anticancer activity, which was further substantiated by comprehensive molecular docking analyses that revealed complex interactions involving hydrophobic contacts, electrostatic forces and hydrogen bonds. Our results would collectively provide invaluable insights into the intricate molecular structure and dynamics of receptor target sites, thereby establishing a solid foundation for the development of novel and potent anticancer agents with optimistic pharmaceutical implications in near future.

The ongoing COVID-19 pandemic has spurred international efforts to discover effective treatments against SARS-CoV-2. The essential oil (EO) of Algerian Origanum vulgare, which was extracted by steam distillation from aerial portions of the plant, contained a variety of bioactive substances that we were able to identify using a combination of gas chromatography–mass spectrometry and infrared spectroscopy (IR). The objective of this work is to ascertain this oil’s organoleptic and physicochemical characteristics. The drug interactions with important proteins involved in SARS-CoV-2 replication were evaluated using molecular docking studies. Certain compounds exhibited a strong affinity for binding, suggesting that they may have the ability to suppress viral activity. The stability and effectiveness of these interactions were validated by molecular dynamics simulations wherein carvacrol complexes demonstrated enhanced structural stability decreased flexibility compactness and decreased solvent exposure in contrast to other ligands. Both carvacrol and thymol are bioavailable and well absorbed according to ADMET analysis however there is a chance of skin irritation and liver toxicity. Carvacrol in particular showed minimal toxicity risks such as blockage of hERG or AMES low CNS permeability and slight long-term toxicity. These findings imply that Origanum vulgare essential oil might be a valuable natural resource for creating more effective COVID-19 treatments.

I use a stochastic model to explore the dynamics of poverty in India from 1952 to 2006 and find that temporal transitions into and out of poverty are common. Model outcomes suggest that transitions out of poverty outnumber transitions into poverty in recent times, but that there is still a nontrivial proportion of individuals transitioning annually into poverty, highlighting the economic fragility of those near the poverty line. There is also a marked persistence of poverty over time, and although this has been slowly declining, past poverty remains a good predictor of current poverty. Particularly concerning in this context are the income trajectories of those in the bottom decile of the income distribution for whom escape from poverty appears infeasible given extant income dynamics. Finally, the dynamics suggest that transitional and persistent poverty are distinct phenomena that require distinct policy responses involving both missing markets and state action.

This is a continuation of [Notes on solutions in Wronskian form to soliton equations: Korteweg–de Vries-type, arXiv:nlin.SI/0603008]. In the present paper, we review solutions to the modified Korteweg–de Vries equation in terms of Wronskians. The Wronskian entry vector needs to satisfy a matrix differential equation set which contains complex operation. This fact makes the analysis of the modified Korteweg–de Vries to be different from the case of the Korteweg–de Vries equation. To derive complete solution expressions for the matrix differential equation set, we introduce an auxiliary matrix to deal with the complex operation. As a result, the obtained solutions to the modified Korteweg–de Vries equation are categorized into two types: solitons and breathers, together with their limit cases. Besides, we give rational solutions to the modified Korteweg–de Vries equation in Wronskian form. This is derived with the help of a Galilean transformed version of the modified Korteweg–de Vries equation. Finally, typical dynamics of the obtained solutions are analyzed and illustrated. We also list out the obtained solutions and their corresponding basic Wronskian vectors in the conclusion part.

We consider a hard core (HC) model with a countable set $\mathbb{Z}$ of spin values on the Cayley tree. This model is defined by a countable set of parameters ${\lambda }_i>0,i\in \mathbb{Z}\setminus \{0\}$. For all possible values of parameters, we give limit points of the dynamical system generated by a function which describes the consistency condition for finite-dimensional measures. Also, we prove that every periodic Gibbs measure for the given model is either translation-invariant or periodic with period two. Moreover, we construct uncountable set of Gibbs measures for this HC model.

Transient performance of nanowire memristors realized using different material systems is discussed. The approach is validated by comparing simulated results with experimental data obtained for a ZnO nanowire memristor. The ZnO nanowire memristors demonstrate bipolar resistive switching with an R_OFF/R_ON ratio of 684 that is 3 times higher than the previous best report. The transient switching model, derived from the physical mechanisms for memristor switching, show a material dependent switching delay greatly influenced by the mobility of the oxygen vacancies. Measured switching delay of 372 µs for ZnO memristor show excellent agreement with the simulated data. The switching delays for other material systems, namely – TiO_x, TaO_x, HfO_x, and ZrO_x are calculated to be 2.5 s, 5.5 ns, 11.8 ps, and 7.15 ps, respectively, for identical device geometry (length 2 µm and diameter 300 nm). Upon scaling devices down to 50 nm, the delay is observed to decrease by 3-4 orders of magnitude. ZrO_x based memristors showed the shortest switching delay owing to a mobility as high as 370 cm²/V-s. Experimental data for ZnO memristors suggest rise and fall times shorter than 7 µs and 10 ns, respectively. Ultralow switching power of 261 µW and 155 µW are achieved for SET and RESET switching, respectively. Measured switching energy less than 83 nJ and slew rates greater than 0.02 V/µs are attained.

We show that if a compact Kähler manifold X admits a cohomologically hyperbolic surjective endomorphism then its Kodaira dimension is non-positive. This gives an affirmative answer to a conjecture of Guedj in the holomorphic case. The main part of the paper is to determine the geometric structure and the fundamental groups (up to finite index) for those X of dimension 3.

We consider a minimal, free action, φ, of the group ℤ^d on the Cantor set X, for d ≥ 1. We introduce the notion of small positive cocycles for such an action. We show that the existence of such cocycles allows the construction of finite Kakutani–Rohlin approximations to the action. In the case, d = 1, small positive cocycles always exist and the approximations provide the basis for the Bratteli–Vershik model for a minimal homeomorphism of X. Finally, we consider two classes of examples when d = 2 and show that such cocycles exist in both.

Let $X$ be a projective variety of dimension $n\ge 1$ over an algebraically closed field of arbitrary characteristic. We prove a Fujiki–Lieberman type theorem on the structure of the automorphism group of $X$. Let $G$ be a group of zero entropy automorphisms of $X$ and $G_0$ the set of elements in $G$ which are isotopic to the identity. We show that after replacing $G$ by a suitable finite-index subgroup, $G/G_0$ is a unipotent group of the derived length at most $n-1$. This result was first proved by Dinh et al. for compact Kähler manifolds.

The one-dimensional Sznajd model "united we stand, divided well fall" is generalized to the square lattice with similar fixed points. Only in two of the variants are the distribution of equilibration times roughly log-normal. Probabilistic generalizations destroyed the "dictatorial" fixed points.

In the Sznajd model of sociophysics on the square lattice, neighbors having the same opinion convince their neighbors of this opinion. We study scaling of the cluster growth. The spreading-of-damage technique is applied for the spread of opinions. We study the time evolution of the damage and compare it with the magnetization evolution. We also compare this model with the Ising model at low temperatures. It was recently shown that the distribution of votes in Brazilian elections follows a power law behavior with exponent ≃ -1.0. A model for elections based on the Sznajd model is proposed. The exponent obtained for the distribution of votes during the transient agrees with that obtained for elections.

We examine and model dynamics in three areas of social cognition: (1) political transformations within Russia, (2) evaluation of political trends in other countries by Russians, and (3) evaluation of Russian stereotypes concerning women. We try to represent consciousness as vectorfields and trajectories in a cognitive state space. We use psychosemantic techniques that allow definition of the state space and the systematic construction of these vectorfields and trajectories and their portrait from research data. Then we construct models to fit them, using multiple regression methods to obtain linear differential equations. These dynamical models of social cognition fit the data quite well. (1) The political transformations were modeled by a spiral repellor in a two-dimensional space of a democratic–totalitarian factor and social depression–optimism factor. (2) The evaluation of alien political trends included a flow away from a saddle toward more stable and moderate political regimes in a 2D space, of democratic–totalitarian and unstable–stable cognitive dimensions. (3) The gender study showed expectations (attractors) for more liberated, emancipated roles for women in the future.

In this paper the kinetics of Muon Catalyzed Fusion (μCF) in H/D/T mixture, considering the muon transfer from hydrogen isotopes (p,d,t) to helium isotopes (³He, ⁴He) in the range of temperatures of 300 K < T < 1300 K at the density of Φ = 1 LHD, is presented. Calculation of cycling rate in different branches of fusion such as dtμ, ptμ, pdμ, ddμ, ttμ and energy gain showed that in certain physical conditions, the H/D/T mixture is comparable to D/T one. Finally the results of this research are compared with the experimental results reported by other researchers; and good agreements were found.

The Ramsauer–Townsend effect in hydrogen is used to force the muonic tritium in suggested heterogeneous solid hydrogen–deuterium–tritium (H/D/T) multilayer system to provide resonance muonic deuterium–tritium molecule formation. The written coupled linear point dynamical equations for the suggested system are solved by Monte-Carlo method using "Lsode" computer code. The obtained results for the optimum layer thicknesses and tritium concentration are compared with the results of solid homogeneous deuterium–tritium system in the same physical condition (temperature, density and tritium concentration). It is shown that for the same physical conditions, the muon cycling coefficient of two isotopes of deuterium–tritium (D/T) has only 3% muon cycling coefficient of suggested heterogeneous solid forced H/D/T fusion system. It is shown that with very little tritium concentration (c_t = 0.005) the obtained muon cycling rate and coefficient are ~ 120 μs^-1 and 165 respectively.

The article presents a dynamic model of exchange, production, and consumption. In a dynamic world, complicated predictions often have to be made. Thus, in this article, the classical exchange model is expanded with a dynamic model specifying the intermediate states toward a static equilibrium, which may or may not be reached. A price mechanism was necessary to develop in order to describe these changes over time. The model is illustrated with two examples of the emergence of division of labor. The robustness of the dynamic model is tested with sensitivity analysis.

In a Potts-like model of Q ethnic groups, we follow Schelling¹ and Meyer-Ortmanns² and simulate the formation of ethnic ghettos as well as their prevention by an increasing social temperature.

The article formulates a dynamic mathematical model where arbitrarily many players produce, consume, exchange, loan, and deposit arbitrarily many goods over time to maximize utility. Consuming goods constitutes a benefit, and producing, exporting, and loaning away goods constitute a cost. Utilities are benefits minus costs, which depend on the exchange ratios and bargaining functions. Three-way exchange occurs when one player acquires, through exchange, one good from another player with the sole purpose of using this good to exchange against the desired good from a third player. Such a triple handshake is not merely a set of double handshakes since the player assigns no interest to the first good in his benefit function. Cognitive and organization costs increase dramatically for higher order exchanges. An exchange theory accounting for media of exchange follows from simple generalization of two-way exchange. The examples of r-way exchange are the triangle trade between Africa, the USA, and England in the 17th and 18th centuries, the hypothetical hypercycle involving RNAs as players and enzymes as goods, and reaction–diffusion processes. The emergence of exchange, and the role of trading agents are discussed. We simulate an example where two-way exchange gives zero production and zero utility, while three-way exchange causes considerable production and positive utility. Maximum utility for each player is reached when exchanges of the same order as the number of players in society are allowed. The article merges micro theory and macro theory within the social, natural, and physical sciences.

We present a cellular-automaton model of a reaction-diffusion excitable system with concentration dependent inhibition of the activator, and study the dynamics of mobile localizations (gliders) and their generators. We analyze a three-state totalistic cellular automaton on a two-dimensional lattice with hexagonal tiling, where each cell connects with 6 others. We show that a set of specific rules support spiral glider-guns (rotating activator-inhibitor spirals emitting mobile localizations) and stationary localizations which destroy or modify gliders, along with a rich diversity of emergent structures with computational properties. We describe how structures are created and annihilated by glider collisions, and begin to explore the necessary processes that generate this kind of complex dynamics.

This paper provides a mathematical dynamic description of the bioenergetic time history of bilataria (multicellular animals with a digestive tract) during feeding, growth and activity. We analyze the dynamics of bioenergy using ordinary differential equations on a compartment model, which we believe could constitute a mathematical foundation. Allometric scaling laws of the quarter type are assumed for all scaling relations in accordance with fractal theory. The paper demonstrates the dynamics by which bilataria respond to activity and feeding. The model is tested against some well-known experiments for fishes.