Simulation of oscillatory processes in the MVSTUDIUM package

The mathematical model and algorithms of oscillatory movements are considered. Various factors affecting the oscillatory process are considered. Oscillatory movements are constructed in the MVSTUDIUM modeling environment. The schemes of three computer models demonstrating oscillatory processes are determined: a model of a pendulum with a non-movable suspension point, a model of a pushing pendulum with friction force and a model of a breaking pendulum. Classes are being built to execute models with embedded properties, as well as with the ability to export the created classes to other models, and embed classes created by the program developer into the model. Creation of 2D and 3D models of oscillatory processes, an experiment behavior map and a virtual stand.

Symbiosis of Electrical and Metabolic Oscillations in Pancreatic β-Cells

Insulin is secreted in a pulsatile pattern, with important physiological ramifications. In pancreatic β-cells, which are the cells that synthesize insulin, insulin exocytosis is elicited by pulses of elevated intracellular Ca2+ initiated by bursts of electrical activity. In parallel with these electrical and Ca2+ oscillations are oscillations in metabolism, and the periods of all of these oscillatory processes are similar. A key question that remains unresolved is whether the electrical oscillations are responsible for the metabolic oscillations via the effects of Ca2+, or whether the metabolic oscillations are responsible for the electrical oscillations due to the effects of ATP on ATP-sensitive ion channels? Mathematical modeling is a useful tool for addressing this and related questions as modeling can aid in the design of well-focused experiments that can test the predictions of particular models and subsequently be used to improve the models in an iterative fashion. In this article, we discuss a recent mathematical model, the Integrated Oscillator Model (IOM), that was the product of many years of development. We use the model to demonstrate that the relationship between calcium and metabolism in beta cells is symbiotic: in some contexts, the electrical oscillations drive the metabolic oscillations, while in other contexts it is the opposite. We provide new insights regarding these results and illustrate that what might at first appear to be contradictory data are actually compatible when viewed holistically with the IOM.

Multiwavelength Quasi-periodic Pulsations in a Stellar Superflare

We present the first multiwavelength simultaneous detection of quasi-periodic pulsations (QPPs) in a superflare (more than a thousand times stronger than known solar flares) on a cool star, in soft X-rays (SXRs, with XMM-Newton) and white light (WL, with Kepler). It allowed for the first ever analysis of oscillatory processes in a stellar flare simultaneously in thermal and nonthermal emissions, conventionally considered to come from the corona and chromosphere of the star, respectively. The observed QPPs have periods 1.5 ± 0.15 hr (SXR) and 3 ± 0.6 hr (WL), and correlate well with each other. The unique relationship between the observed parameters of QPPs in SXR and WL allowed us to link them with oscillations of the electric current in the flare loop, which directly affect the dynamics of nonthermal electrons and indirectly (via ohmic heating) the thermal plasma. These findings could be considered in favor of the equivalent LCR contour model of a flare loop, at least in the extreme conditions of a stellar superflare.

The dialectics of cyclicity in the development of law.

The dialectic of cyclicity in the system of dual natural and positive law, as the transition from one opposite to another, involution to evolution, quantitative transformations into qualitative and actually regular cyclicity of crises and stability in the legal system is studied. The dialectic of cyclicity in law occurs as constant oscillating processes of transition from one opposite to another, natural law into positive, involution into evolution, quantity into quality, crisis into stability, and development in a circle gradually turns into a spiral. Defining and substantiating the phases and stages of the cycle allows us to demonstrate the development of a particular cycle and the driving mechanisms of this transformation – the laws of dialectics, in particular, the unity and struggle of opposites in law, the transition from quantity to quality, denial of the old and so on. Oscillatory processes are manifested in opposites of phases and stages of cycles, and small cycles of development of law are embedded in large ones, where each cycle is part of a larger cycle, and that in turn is even larger, and so on. The end of one cycle leads to the transformation of the legal system and its manifestation in a new form and content at a new level of the spiral of development. Ways to overcome the crisis in the legal system should be sought, first of all, in the updated methodological principles of cyclicality in jurisprudence based on the ideas of natural law, based on the principles and laws of dialectics, laws of philosophy of law, and in combination with other branches of modern knowledge.

Research of the influence of the operating parameters of a mobile lift on the oscillatory processes occurring during the work operations

The article provides an analysis of the results of an experimental study of oscillatory processes occurring in mobile lifts with working platforms (MLWP) during the working operations. According to the developed research methodology, the results of measurements of acceleration along the horizontal and vertical axes of the machine at the point of articulation of the boom and at the point of attachment of the working platform to the boom were obtained and analysed. The analysis of the obtained oscillograms indicates that the greatest oscillations occur at the point of attachment of the working platform to the boom along the vertical axis. Accordingly, a detailed analysis of the influence of the operating parameters of the mobile lift on the oscillatory processes occurring during the operation of the machine at the point of attachment of the working platform to the boom along the vertical axis was carried out.

Alpha blocking and 1/fβ spectral scaling in resting EEG can be accounted for by a sum of damped alpha band oscillatory processes

The dynamical and physiological basis of alpha band activity and 1/fβ noise in the EEG are the subject of continued speculation. Here we conjecture, on the basis of empirical data analysis, that both of these features may be economically accounted for through a single process if the resting EEG is conceived of being the sum of multiple stochastically perturbed alpha band damped linear oscillators with a distribution of dampings (relaxation rates). The modulation of alpha-band and 1/fβ noise activity by changes in damping is explored in eyes closed (EC) and eyes open (EO) resting state EEG. We aim to estimate the distribution of dampings by solving an inverse problem applied to EEG power spectra. The characteristics of the damping distribution are examined across subjects, sensors and recording condition (EC/EO). We find that there are robust changes in the damping distribution between EC and EO recording conditions across participants. The estimated damping distributions are found to be predominantly bimodal, with the number and position of the modes related to the sharpness of the alpha resonance and the scaling (β) of the power spectrum (1/fβ). The results suggest that there exists an intimate relationship between resting state alpha activity and 1/fβ noise with changes in both governed by changes to the damping of the underlying alpha oscillatory processes. In particular, alpha-blocking is observed to be the result of the most weakly damped distribution mode becoming more heavily damped. The results suggest a novel way of characterizing resting EEG power spectra and provides new insight into the central role that damped alpha-band activity may play in characterising the spatio-temporal features of resting state EEG.

COSMO-Onset: A Neurally-Inspired Computational Model of Spoken Word Recognition, Combining Top-Down Prediction and Bottom-Up Detection of Syllabic Onsets

Recent neurocognitive models commonly consider speech perception as a hierarchy of processes, each corresponding to specific temporal scales of collective oscillatory processes in the cortex: 30–80 Hz gamma oscillations in charge of phonetic analysis, 4–9 Hz theta oscillations in charge of syllabic segmentation, 1–2 Hz delta oscillations processing prosodic/syntactic units and the 15–20 Hz beta channel possibly involved in top-down predictions. Several recent neuro-computational models thus feature theta oscillations, driven by the speech acoustic envelope, to achieve syllabic parsing before lexical access. However, it is unlikely that such syllabic parsing, performed in a purely bottom-up manner from envelope variations, would be totally efficient in all situations, especially in adverse sensory conditions. We present a new probabilistic model of spoken word recognition, called COSMO-Onset, in which syllabic parsing relies on fusion between top-down, lexical prediction of onset events and bottom-up onset detection from the acoustic envelope. We report preliminary simulations, analyzing how the model performs syllabic parsing and phone, syllable and word recognition. We show that, while purely bottom-up onset detection is sufficient for word recognition in nominal conditions, top-down prediction of syllabic onset events allows overcoming challenging adverse conditions, such as when the acoustic envelope is degraded, leading either to spurious or missing onset events in the sensory signal. This provides a proposal for a possible computational functional role of top-down, predictive processes during speech recognition, consistent with recent models of neuronal oscillatory processes.

Oscillation or not – why we can and need to know

Neural oscillations are pivotal to brain function and cognition, but they can be difficult to identify. Researchers engage in careful experimentation to identify their presence, ruling out non-oscillatory processes that could give rise to a similar response. Recently, Doelling and Assaneo have argued against these efforts on the basis that oscillators are heterogeneous, which makes the line to non-oscillators blurred and thereby meaningless to draw. Here, we offer our opposing viewpoint, arguing that we can know whether oscillations are involved, and that we need to know. First, we can know because there are unique properties that only oscillators have, which can be reliably used to identify them – the line is not blurred. These unique properties include eigenfrequency, Arnold Tongue, convergence, and independence. Second, we need to know because there are shared properties, which all oscillators or all oscillators within a subclass have. These shared properties comprise all the information we get once we know there is an oscillator, including neurophysiological, functional, and methodological properties – the fruits of decades of research. We argue that identifying oscillators is crucial for the advancement of research fields as it constrains the possible neural dynamics involved and allows us to make informed predictions on a variety of levels. While neural oscillations are the start and not the end, we have to reach that start.

Simulation of the Propagation of Electromagnetic Oscillations by the Method of the Modified Equation of the Telegraph Line

The article considers the physical processes associated with the propagation of electromagnetic oscillations in a long line, the size of which is the same or slightly greater than the length of the electromagnetic wave (not more than ten times). As a research method, the differential-symbolic method is used, which is applied to the modified equation of the telegraph line. The boundary conditions for the two-point problem as well as additional parameters that are coefficients for the first derivatives in terms of coordinate and time in comparison with the classical equation of the telegraph line are considered as parameters for controlling the process of propagation of electromagnetic oscillations. Based on the differential-symbolic method, the boundary conditions of the two-point problem are found, under which the most characteristic oscillatory processes are realized in a long line. Based on the research, it is possible to draw conclusions about the effectiveness of analytical methods for the analysis of specific technical objects and control of the processes that take place in them.