Amplitude modulations and resonant decay of excited oscillons.

We show that the decay of strongly excited oscillons in a single vacuum model reveals a chaotic, fractal-like pattern very much like the one found in kink-antikink collisions in the ϕ^{4} model. This structure can be attributed to the resonant energy transfer mechanism triggered by the modulations of amplitudes of constituent oscillons which form the excited oscillon. We also find evidence that such modulations arise as a motion of two quasibreathers inside the constituent oscillon.

Study of the frequencies of erythrocyte abnormalities as in situ biomarkers of genotoxic risk of chemicals in special fish stock in water supply reservoirs.

In three water-supply reservoirs in the catchment area of the Odra River (Czech Republic), a special fish stock was monitored for control of health to estimate the mutagenic effect of chemicals. The results contribute to obtaining initial information about the morphology of erythrocyte abnormalities classified in 21 categories in 16 fish species in reservoirs with abundant salmonids (the Morávka Reservoir) or with the prevalence of cyprinids (the Kružberk and Šance Reservoirs), not directly exposed to the adverse environmental effects such as industrial, urban, agricultural and intensive farming activities. The different intensities and prevalence of nuclear abnormalities (NA) and cytoplasmic abnormalities (CA) in fish from the same reservoir habitat show that to be able to obtain an objective view of the genotoxic risk of chemicals, it is necessary to respect the different requirements of the fish for the exploitation of the food available in the biotope and to subject all representatives of piscivorous, omnivorous and benthophagous fishes in the reservoir to cytogenetic analysis.

Reducing the negative impact of accidents associated with the release of dangerous substances to environment.

Background: The article is concerned with an evaluation of the current state of emergency readiness of industrial companies in the event of dangerous substance leakage and with a presentation of textile sorbents used for the purposes of capturing an escaped substance.

Methods: A part of the article is concerned with the experimental designation of sorption capacity of hydrophobic, chemical, and universal sorption mats for chosen polar (water and alcohol) and non-polar (oil and gasoline) liquids. Experiments were realized according to Standard Test Method for Sorbent Performance of Adsorbents for use on Crude Oil and Related Spills, American Society for Testing and Materials (ASTM F726-17), type I.

Peak systolic velocity ratio for evaluation of internal carotid artery stenosis correlated with plaque morphology: substudy results of the ANTIQUE study.

Background: Accurate assessment of carotid stenosis severity is important for proper patient management. The present study aimed to compare the evaluation of carotid stenosis severity using four duplex sonography (DUS) measurements, including peak systolic velocity (PSV), PSV ratio in stenosis and distal to stenosis (PSV ratio), end-diastolic velocity (EDV), and B-mode, with computed tomography angiography (CTA), and to evaluate the impact of plaque morphology on correlation between DUS and CTA.

Methods: Consecutive patients with carotid stenosis of ≥40% examined using DUS and CTA were included.

Mechanization of a scalar field theory in 1+1 dimensions: Bogomol'nyi-Prasad-Sommerfeld mechanical kinks and their scattering.

We present an updated version of a general-purpose collective coordinate model that aims to fully map out the dynamics of a single scalar field in 1+1 dimensions. This is achieved by a procedure that we call a mechanization, in which we reduce the infinite number of degrees of freedom down to a finite and controllable number by chopping the field into flat segments connected via joints. In this paper we introduce two new ingredients to our procedure.

An economic evaluation of the effectiveness of telemedicine in hematooncology.

The article examines the effectiveness of remote monitoring and the evaluation of facts about patients with hematologic malignancies using telemedicine based on SMART technologies. The project was carried out in the Department of Haematooncology of the University Hospital Ostrava. Its objective was to test the efficacy of telemedicine in the treatment of patients with blood cancer.

Unconstrained Lagrangian Variational Principles for the Einstein Field Equations.

This paper deals with the problem of establishing a systematic theoretical formulation of variational principles for the continuum gravitational field dynamics of classical General Relativity (GR). In this reference, the existence of multiple Lagrangian functions underlying the Einstein field equations (EFE) but having different physical connotations is pointed out. Given validity of the Principle of Manifest Covariance (PMC), a set of corresponding variational principles can be constructed.

Implementation of a navigation system: Economic verification in a local hospital.

Healthcare, like other industries, is increasingly using smart technologies, which also include intelligent/smart wayfinding navigation. The focus of this article, as part of the research project (its second step), was to analyze the economic effectiveness of the introduction of the wayfinding system in a local hospital in the Czech Republic. In the first phase/step of the project, possible variants of the solution were identified, verification of possible functioning, and a questionnaire survey was conducted among employees and patients regarding the waste of time in search of destination and preferences of various forms of navigation.

On the Monte Carlo weights in multiple criteria decision analysis.

In multiple-criteria decision making/aiding/analysis (MCDM/MCDA) weights of criteria constitute a crucial input for finding an optimal solution (alternative). A large number of methods were proposed for criteria weights derivation including direct ranking, point allocation, pairwise comparisons, entropy method, standard deviation method, and so on. However, the problem of correct criteria weights setting persists, especially when the number of criteria is relatively high.

Certain predictors of coping with stress in adolescents.

Background: The purpose of the study was to search for variables that show a relationship with coping with stress as well as to search for the possibility of predicting a stress coping mechanism in the studied adolescents. Two questions were formulated in the study: Are mental resilience and communication with peers significant predictors of coping with stress in the studied group? To what extent will the analysed predictors explain individual strategies to cope with stress?

Participants And Procedure: The study involved three tools: the Resilience Measurement Scale (RMS-18), the Coping Inventory for Stressful Situations Questionnaire (CISS), and the Scale of Communication of Adolescents with Peers (SCAP). The study was carried out on a randomly selected group of 546 adolescents.

A Self-Controlled and Self-Healing Model of Bacterial Cells.

A new kind of self-assembly model, morphogenetic (M) systems, assembles spatial units into larger structures through local interactions of simpler components and enables discovery of new principles for cellular membrane assembly, development, and its interface function. The model is based on interactions among three kinds of constitutive objects such as tiles and protein-like elements in discrete time and continuous 3D space. It was motivated by achieving a balance between three conflicting goals: biological, physical-chemical, and computational realism.

The Impact of Different Factors on Repeat Visits to Selected International Tourism Enterprises: Case Study From Czechia.

The aim of this article is to identify the influence of the different factors on the repeat visits to selected international tourism enterprises based on the responses of customers in Czechia. The selected factors were divided into three main groups: service, environment, and offer, and each of these groups consists of other different factors. Primary data were analyzed using SPSS software.

The first case report of multiple thoracic vertebrae fractures caused by a low-voltage electric shock.

Background: This paper describes a unique case-the first case of multiple fractures of the thoracic vertebrae caused by a low-voltage electric shock.

Case Presentation: A 22-year-old male patient was diagnosed with compression fractures of Th2-Th6 caused by a muscle spasm resulting from an electric shock. The patient was treated conservatively using a cervico-thoracic support corset.

Traversable Wormholes in General Relativity.

Blázquez-Salcedo et al. [Phys. Rev.

Citizens' Preparedness to Deal with Emergencies as an Important Component of Civil Protection.

The main purpose of this paper is to point out a new approach in evaluating the preparedness of the population of a selected city for civil protection and its response to emergencies. Using new approaches, it evaluates a subjective questionnaire survey in combination with the objective state thanks to a mathematical approach and its subsequent verification on a specific example. The proposed approaches are then verified by experimental surveys in the selected city.

Zernike Moment Based Classification of Cosmic Ray Candidate Hits from CMOS Sensors.

Reliable tools for artefact rejection and signal classification are a must for cosmic ray detection experiments based on CMOS technology. In this paper, we analyse the fitness of several feature-based statistical classifiers for the classification of particle candidate hits in four categories: spots, tracks, worms and artefacts. We use Zernike moments of the image function as feature carriers and propose a preprocessing and denoising scheme to make the feature extraction more efficient.

The evaluation of COVID-19 prediction precision with a Lyapunov-like exponent.

In the field of machine learning, building models and measuring their performance are two equally important tasks. Currently, measures of precision of regression models' predictions are usually based on the notion of mean error, where by error we mean a deviation of a prediction from an observation. However, these mean based measures of models' performance have two drawbacks.

Physical Properties of Schwarzschild-deSitter Event Horizon Induced by Stochastic Quantum Gravity.

A new type of quantum correction to the structure of classical black holes is investigated. This concerns the physics of event horizons induced by the occurrence of stochastic quantum gravitational fields. The theoretical framework is provided by the theory of manifestly covariant quantum gravity and the related prediction of an exclusively quantum-produced stochastic cosmological constant.

The Quantum Regularization of Singular Black-Hole Solutions in Covariant Quantum Gravity.

An excruciating issue that arises in mathematical, theoretical and astro-physics concerns the possibility of regularizing classical singular black hole solutions of general relativity by means of quantum theory. The problem is posed here in the context of a manifestly covariant approach to quantum gravity. Provided a non-vanishing quantum cosmological constant is present, here it is proved how a regular background space-time metric tensor can be obtained starting from a singular one.

The Principle of Covariance and the Hamiltonian Formulation of General Relativity.

The implications of the general covariance principle for the establishment of a Hamiltonian variational formulation of classical General Relativity are addressed. The analysis is performed in the framework of the Einstein-Hilbert variational theory. Preliminarily, customary Lagrangian variational principles are reviewed, pointing out the existence of a novel variational formulation in which the class of variations remains unconstrained.

The Heisenberg Indeterminacy Principle in the Context of Covariant Quantum Gravity.

The subject of this paper deals with the mathematical formulation of the Heisenberg Indeterminacy Principle in the framework of Quantum Gravity. The starting point is the establishment of the so-called time-conjugate momentum inequalities holding for non-relativistic and relativistic Quantum Mechanics. The validity of analogous Heisenberg inequalities in quantum gravity, which must be based on strictly physically observable quantities (i.

Quantum-Gravity Stochastic Effects on the de Sitter Event Horizon.

The stochastic character of the cosmological constant arising from the non-linear quantum-vacuum Bohm interaction in the framework of the manifestly-covariant theory of quantum gravity (CQG theory) is pointed out. This feature is shown to be consistent with the axiomatic formulation of quantum gravity based on the hydrodynamic representation of the same CQG theory developed recently. The conclusion follows by investigating the indeterminacy properties of the probability density function and its representation associated with the quantum gravity state, which corresponds to a hydrodynamic continuity equation that satisfies the unitarity principle.

Constraining LQG Graph with Light Surfaces: Properties of BH Thermodynamics for Mini-Super-Space, Semi-Classical Polymeric BH.

This work participates in the research for potential areas of observational evidence of quantum effects on geometry in a black hole astrophysical context. We consider properties of a family of loop quantum corrected regular black hole (BHs) solutions and their horizons, focusing on the geometry symmetries. We study here a recently developed model, where the geometry is determined by a metric quantum modification outside the horizon.

Morphogenetic systems: Models and experiments.

M systems are mathematical models of morphogenesis developed to gain insights into its relations to phenomena such as self-assembly, self-controlled growth, homeostasis, self-healing and self-reproduction, in both natural and artificial systems. M systems rely on basic principles of membrane computing and self-assembly, as well as explicit emphasis on geometrical structures (location and shape) in 2D, 3D or higher dimensional Euclidean spaces. They can be used for principled studies of these phenomena, both theoretically and experimentally, at a computational level abstracted from their detailed implementation.

Spatial lag effect of aridity and nitrogen deposition on Scots pine (Pinus sylvestris L.) damage.

Scots pine (Pinus sylvestris L.) is a widespread tolerant forest tree-species; however, its adaptability to environmental change differs among sites with various buffering capacity. In this study, we compared the spatial effects of aridity index (AI) and nitrogen deposition (ND) on biomass density in natural and man-made pine stands of differing soil fertility using geographically weighted multiple lag regression.