Slow Motion Research Articles

Exploring the Behaviors of Initiated Progressive Failure and Slow‐Moving Landslides in Los Angeles Using Satellite InSAR and Pixel Offset Tracking

AbstractCatastrophic landslides are often preceded by slow, progressive, accelerating deformation that differs from the persistent motion of slow‐moving landslides. Here, we investigate the motion of a landslide that damaged 12 homes in Rolling Hills Estates (RHE), Los Angeles, California on 8 July 2023, using satellite‐based synthetic aperture radar interferometry (InSAR) and pixel tracking of satellite‐based optical images. To better understand the precursory motion of the RHE landslide, we compared its behavior with local precipitation and with several slow‐moving landslides nearby. Unlike the slow‐moving landslides, we found that RHE was a first‐time progressive failure that failed after one of the wettest years on record. We then applied a progressive failure model to interpret the failure mechanisms and further predict the failure time from the pre‐failure movement of RHE. Our work highlights the importance of monitoring incipient slow motion of landslides, particularly where no discernible historical displacement has been observed.

Spontaneous near-inertial wave generation from mesoscale eddy: Energy transformation

The energy transformation between inertial oscillations (IOs), near-inertial waves (NIWs), and mesoscale eddies during spontaneous NIW generation is analyzed by the kinetic energy equations of the multiple temporal–spatial scale interaction between slow and fast motions and then quantitatively estimated by numerical simulations. The evolution of perturbed quasi-geostrophic mesoscale eddies is accompanied by IOs. The nonlinear interaction of IOs and mesoscale eddies results in spontaneous energy transfer from mesoscale eddies to NIWs. However, IOs act as catalysts in the spontaneous NIW energy transformation process, because there is no energy transfer between NIWs and IOs for longer than one inertial period and NIW energy is entirely transferred from mesoscale eddies. The energy conversion rate (ECR) from a propagating eddy to NIWs is significantly enhanced by the resonance of NIWs and the nonlinear coupling of IOs and mesoscale eddies during the spontaneous NIW generation. The time-averaged NIW ECR from a propagating an anti-cyclonic mesoscale eddy (AE) is approximately 5.725 × 10−6 Wm−2 and nearly 16 times higher than those from the standing AE. The magnitude of global near-inertial kinetic energy generated spontaneously from mesoscale eddies is approximately on the order of 2 GW. Therefore, the spontaneous adjustment of mesoscale eddies is a non-negligible NIW generation mechanism and plays a crucial role in the process of supplying energy from mesoscale eddies to the diapycnal mixing in the ocean interior.

Assessing blink dynamics with non-noticeable method

PurposeThe purpose of the study was to demonstrate the feasibility of blink dynamics with a contactless, non-noticeable method without any visible light being reflected to the participant’s eye by the device, and to investigate the blink dynamics parameters in 39 participants whose blink dynamics were examined with this method. It was also aimed to explain the potential of corneal topography devices for non-noticeable blink dynamics and elucidate some tips to device manufacturers to make them practical. MethodsA one-minute real-time video image in the meibography module of the scheimpflug camera-based corneal topography device was recorded in the slow motion mode of the mobile phone. Detailed analysis of blink dynamics was made by advancing the video images manually at 10 ms intervals. Lid Closing Time (LCT), Lid Opening Time (LOT), third Interblink Interval times (IBI(3)), fifth Interblink Interval times (IBI(5)), Number of Blinks Per Minute (NoB), Number of Complete Blinks Per Minute (NoCB), Number of Incomplete Blinks Per Minute (NoICB) were investigated. ResultsThe average NoB, NoCB, and NoICB (blinks/minute) with ± standard deviation (SD) values were found to be 22.9 ± 14.4; 14.5 ± 12.4 and 8.4 ± 8, respectively. The average IBI(3) time(seconds) with ± SD was measured as 3.4 ± 4.5. The average IBI(5) time (seconds) with ± SD was 3.9 ± 3.7 The average LCT time (milliseconds) with ± SD was found to be 91.9 ± 36.9 in the 4 different blinks analyzed. The average LOT time (milliseconds) with ± SD was found to be 582.6 ± 196.5 in the 3 different blinks analyzed. ConclusionsBlink dynamics can be examined in detail with corneal topography devices in a non-contact, no visible light, and most importantly, non-noticeable manner. Existing video imaging modules of corneal topography devices have the potential to investigate blink dynamics. It is anticipated that the clinical use of blink dynamics, which can be performed practically, will increase, particularly in the monitoring of ocular surface and neurological diseases.

Conformations of influenza A M2 protein in DOPC/DOPS and E. coli native lipids and proteins

We compared the conformations of the transmembrane domain (TMD) of influenza A M2 (IM2) protein reconstituted in 1,2-dioleoyl-sn-glycero-3-phosphocholine/1,2-dioleoyl-sn-glycero-3-phospho-L-serine (DOPC/DOPS) bilayers to those in isolated Escherichia coli (E. coli) membranes, having preserved its native proteins and lipids. IM2 is a single-pass transmembrane protein known to assemble into a homo-tetrameric proton channel. To represent this channel, we made a construct containing the IM2’s TMD region flanked by the juxtamembrane residues. The single cysteine substitution, L43C, of leucine located in the bilayer polar region was paramagnetically tagged with a methanethiosulfonate nitroxide label for the electron spin resonance (ESR) study. For this particular residue, we probed the conformations of the spin-labeled IM2 reconstituted in DOPC/DOPS and isolated E. coli membranes using continuous-wave ESR and double electron-electron resonance (DEER) spectroscopy. The total protein-to-lipid molar ratio spanned the range from 1:230 to 1:10,400. The continuous-wave ESR spectra corresponded to very slow spin-label motion in both environments. In all cases, the DEER data were reconstructed into distance distributions with well-resolved peaks at 1.68 and 2.37 nm in distance and amplitude ratios of 1.41 ± 0.2 and 2:1, respectively. This suggests four nitroxide spin labels located at the corners of a square, indicative of an axially symmetric tetramer. The distance modeling of DEER data with molecular modeling software applied to the NMR molecular structures (PDB: 2L0J) confirmed the symmetry and closed state of the C-terminal exit pore of the IM2 TMD tetramer in agreement with the model. Thus, we can conclude that, under conditions of pH 7.4 used in this study, IM2 TMD has similar conformations in model lipid bilayers and membranes made of native E. coli lipids and proteins of comparable thickness and fluidity, notwithstanding the complexity of the E. coli membranes caused by their lipid diversity and the abundance of integral and peripheral membrane proteins.

To plasma electrons motion theory in high-frequency fields

The article is dedicated to the kinetic theory of plasma, where the problem of interaction of high-frequency electric fields with weakly non-uniform plasma is investigated using kinetic equations with binary collision integrals for plasma particles. A new methodology for determining the expression of the averaged highfrequency pressure force is proposed based on solving the kinetic equation and using the method of successive approximations (separation of slow motions and fast oscillations) under the limiting conditions. An expression for the averaged quasi-potential force is derived based on the kinetic equation for the electron distribution function in weakly inhomogeneous magnetoactive plasma, taking into account electrons collisions with fixed ions and the presence of a longitudinally inhomogeneous high-frequency electric field using wellknown methods of theoretical and mathematical physics, such as successive approximations, averaging over the effective field oscillation period, and integration over trajectories. The amplitude of the field is a slowly varying function in both time and space coordinates. The obtained expression allows us to estimate the influence of collisions of plasma particles on the Miller force, and under limiting conditions it coincides with the known expressions for the high-frequency pressure force derived from the equation of plasma electrons motion in high-frequency fields. In all calculations, the contribution of the magnetic component of the electromagnetic field is neglected, which is quite justified for the longitudinal electric field.

Horses, gender, and (queer) masculine desire, or how experimental found footage film recycles three Hollywood films

Abstract Although the experimental found footage film recycles Hollywood films so that the outcome may radically differ from the original story, there are no accounts on how it adapts images from mainstream cinema to represent human–animal relations, linking to gender and masculinity. To fill this gap, I discuss how experimental film Horsey recycles footage from three Hollywood productions—Reflections in a Golden Eye, The Swimmer, and The Black Stallion—to construct a new narrative, which displays a very close conformity to the prior text, shifting the focus to human–horse interactions. Raising questions about the traditional understanding, scope, and limits of adaptation in avant-garde film studies, Horsey fits in with the broader tradition of cinematic recycling of mainstream cinema as it exemplifies intertextuality as a direct form of quotation, taking quotation as appropriation through cuts, detournement, compilation and free association. Particularly, following Guy Barefoot’s understanding of adaptation as an intertextual form of recycling, Horsey is distinctive in its sole use of found footage from the three Hollywood films as it fully acknowledges the recycled material, strongly alluding to the original stories, and simultaneously re-processes them through a collage of pre-used footage, slow motion, washed-out colours, and an altered soundtrack. Despite appearing to merely extract images and sounds from Reflections, The Swimmer, and The Black Stallion, Horsey emerges as a productive site for recycling Hollywood cinema, placing it into new contexts and audio-visual configurations and offering more complex, engaging ways of looking at how humans connect to horses.

Evaluating the motional timescales contributing to averaged anisotropic interactions in MAS solid-state NMR

Abstract. Dynamic processes in molecules can occur on a wide range of timescales, and it is important to understand which timescales of motion contribute to different parameters used in dynamics measurements. For spin relaxation, this can easily be understood from the sampling frequencies of the spectral-density function by different relaxation-rate constants. In addition to data from relaxation measurements, determining dynamically averaged anisotropic interactions in magic-angle spinning (MAS) solid-state NMR allows for better quantification of the amplitude of molecular motion. For partially averaged anisotropic interactions, the relevant timescales of motion are not so clearly defined. Whether the averaging depends on the experimental methods (e.g., pulse sequences) or conditions (e.g., MAS frequency, magnitude of anisotropic interaction, radio-frequency field amplitudes) is not fully understood. To investigate these questions, we performed numerical simulations of dynamic systems based on the stochastic Liouville equation using several experiments for recoupling the dipolar coupling, chemical-shift anisotropy or quadrupolar coupling. As described in the literature, the transition between slow motion, where parameters characterizing the anisotropic interaction are not averaged, and fast motion, where the tensors are averaged leading to a scaled anisotropic quantity, occurs over a window of motional rate constants that depends mainly on the strength of the interaction. This transition region can span 2 orders of magnitude in exchange-rate constants (typically in the microsecond range) but depends only marginally on the employed recoupling scheme or sample spinning frequency. The transition region often coincides with a fast relaxation of coherences, making precise quantitative measurements difficult. Residual couplings in off-magic-angle experiments, however, average over longer timescales of motion. While in principle one may gain information on the timescales of motion from the transition area, extracting such information is hampered by low signal-to-noise ratio in experimental spectra due to fast relaxation that occurs in the same region.

Wearable Loops for Dynamic Monitoring of Joint Flexion: A Machine Learning Approach

We present a machine learning driven system to monitor joint flexion angles during dynamic motion, using a wearable loop-based sensor. Our approach uses wearable loops to collect transmission coefficient data and an Artificial Neural Network (ANN) with fine-tuned parameters to increase accuracy of the measured angles. We train and validate the ANN for sagittal plane flexion of a leg phantom emulating slow motion, walking, brisk walking, and jogging. We fabricate the loops on conductive threads and evaluate the effect of fabric drift via measurements in the absence and presence of fabric. In the absence of fabric, our model produced a root mean square error (RMSE) of 5.90°, 6.11°, 5.90°, and 5.44° during slow motion, walking, brisk walking, and jogging. The presence of fabric degraded the RMSE to 8.97°, 7.21°, 9.41°, and 7.79°, respectively. Without the proposed ANN method, errors exceeded 35.07° for all scenarios. Proof-of-concept results on three human subjects further validate this performance. Our approach empowers feasibility of wearable loop sensors for motion capture in dynamic, real-world environments. Increasing speed of motion and the presence of fabric degrade sensor performance due to added noise. Nevertheless, the proposed framework is generalizable and can be expanded upon in the future to improve upon the reported angular resolution.

Quasielastic neutron scattering study on low-hydrated myoglobin inside silica nanopores

In this study, nanosecond-scale dynamics of low-hydrated myoglobin (Mb) encapsulated in mesoporous silica (MPS) with 7.8 nm pores was investigated by using high resolution (energy resolution: 1 μeV) neutron backscattering spectroscopy. The apparent hydration level of the encapsulated myoglobin was 0.06, which was deduced by assuming a uniform distribution of water within myoglobin encapsulated mesoporous silica. The mean square displacement of myoglobin derived from an elastic fixed-window scan was essentially proportional to temperature in the range 120–300 K, indicating the absence of dynamical transition induced by the onset of translational diffusion in the hydration D2O. Since the width of quasielastic neutron scattering (QENS) peaks of the encapsulated Mb was Q-independent at 220, 240, and 265 K, the observed nanosecond-scale dynamics was attributed to internal motions of the encapsulated Mb, such as slow motions of amino acid groups or side chains. The fraction of immobile H-atoms in Mb was estimated to be above 0.8, which was larger than that for a free protein with a similar molecular weight to Mb. The large immobile fraction indicates that the nanosecond-scale motions of amino acid residues and side chains in the vicinity of the pore wall are restricted by the interfacial interactions with the rigid pore wall.

#1189 Сorrelations between laser doppler flowmetry spectral indicators and glycated hemoglobin level in patients with diabetic nephropathy

Abstract Background and Aims Diabetic microangiopathy is a specific vascular complication of diabetes mellitus type 2, which matters to patients' mortality and individual prognosis. Therefore, an important problem is the development of non-invasive methods for the diagnosis of diabetic microangiopathy, such as laser Doppler flowmetry (LDF). This work aimed to analyze some correlations between LDF spectral indicators and the level of glycated hemoglobin in patients with chronic kidney disease and type 2 diabetes. Method The study included 55 patients (26 men and 29 women) with type 2 diabetes mellitus. The age of patients was 58-77 years. The duration of diabetes was more than 5 years. All patients had chronic kidney disease (stage C3-C4) caused by diabetic nephropathy. For Laser Doppler flowmetry we used the “LDF 100C” system (“Biopac Instruments”, USA). Each patient had a 10-minute LDF registration on the skin of the rear of the foot. Using the special software, we have assessed slow, respiratory and pulse flux motion contribution and flux motion index. The next step was a correlation analysis with the glycated hemoglobin level. Results There were several correlations of the spectral LDF indicators with the level of glycated hemoglobin (Table 1). Thus, a negative correlation with the level of glycated hemoglobin was observed for the flux motion index (p=0.04) and the contribution of slow flux motion (p=0.03). On the contrary, for the contribution of pulse flux motion, there was detected a positive correlation with the level of glycated hemoglobin (p<0.01) (Fig. 1). Conclusion Correlations of LDF indicators with the level of glycated hemoglobin can be explained with the correlation of the diabetic microangiopathy progression with the effectiveness of glycemic control. Hyperglycemia is a key pathogenic factor of type 2 diabetes mellitus and its complications. Consequently, in patients with ineffective or less effective glycemic control, a more significant development of diabetic microangiopathy should be expected. An increase in the contribution of pulse flux motion in the laser Doppler flowmetry use guidelines is regarded as an increase in the role of the pulse wave in microcirculatory blood flow modulation. The cause of the latter is most likely a more intensive remodeling of the walls of arterioles against the background of a higher frequency of hyperglycemia episodes. The negative correlation of the contribution of slow flux motion can be explained by a violation of the local mechanisms of microcirculation modulation. The cause of this disorder is the morphofunctional restructuring of the microvessels themselves, the defeat of smooth myocytes in the wall of arterioles and venules, including pacemaker cells, with a violation of the automatic contractile activity of smooth myocytes, as well as endothelial. These factors lead to a shift in the balance of regulation towards systemic factors, which is reflected in the decrease of the flux motion index. A decrease in the flux motion index is regarded as a microcirculation deficiency, which was detected in all patients with type 2 diabetes mellitus. Thus, correlations of the spectral LDF indicators with the level of glycated hemoglobin corresponds to modern ideas about the pathogenesis of diabetic microangiopathy in type 2 diabetes mellitus. These data can be an additional argument in favor of the further development of improving laser Doppler flowmetry using for the tasks of non-invasive diagnosis of microvascular disorders in patients with type 2 diabetes mellitus. The reported study was funded by RFBR, project number 19-315-90080.

Mobility of sodium ions in agarose gels probed through combined single- and triple-quantum NMR

Metal ions, including biologically prevalent sodium ions, can modulate electrostatic interactions frequently involved in the stability of condensed compartments in cells. Quantitative characterization of heterogeneous ion dynamics inside biomolecular condensates demands new experimental approaches. Here we develop a 23Na NMR relaxation-based integrative approach to probe dynamics of sodium ions inside agarose gels as a model system. We exploit the electric quadrupole moment of spin-3/2 23Na nuclei and, through combination of single-quantum and triple-quantum-filtered 23Na NMR relaxation methods, disentangle the relaxation contribution of different populations of sodium ions inside gels. Three populations of sodium ions are identified: a population with bi-exponential relaxation representing ions within the slow motion regime and two populations with mono-exponential relaxation but at different rates. Our study demonstrates the dynamical heterogeneity of sodium ions inside agarose gels and presents a new experimental approach for monitoring dynamics of sodium and other spin-3/2 ions (e.g. chloride) in condensed environments.

Impact of Tutorial Modes with Different Time Flow Rates in Virtual Reality Games

Virtual reality's (VR) unique affordances compared to traditional media have produced innovative interaction modes and tutorial methodologies in VR games. Existing research predominantly focuses on the performance of VR tutorial modes, such as the placement of text and diagrams within tutorial content. However, few studies have delved into other attributes of tutorials. This study categorizes 4 VR game tutorial modes based on time flow: (1) traditional instruction screen, (2) slow motion, (3) bullet time, and (4) context-sensitive mode. This paper evaluates the impact of these 4 VR game tutorial modes with varying time flow rates on controls learnability, engagement-related outcomes, and player performance. We conducted a between-subjects experiment with 59 participants. Results indicated that bullet time significantly enhanced controls learnability, reduced cognitive load, and improved player performance when compared to other tutorial modes. Our research contributes to a more comprehensive understanding of VR game tutorials and offers practical guidance for game designers, underscoring the potential of bullet time to enhance learnability and game experience.

Dynamics of Linkers in Metal-Organic Framework Glasses.

Metal-organic framework (MOF) glasses have emerged as a new class of organic-inorganic hybrid glass materials. Considerable efforts have been devoted to unraveling the macroscopic dynamics of MOF glasses by studying their rheological behavior; however, their microscopic dynamics remain unclear. In this work, we studied the effect of vitrification on linker dynamics in ZIF-62 by solid-state 2H nuclear magnetic resonance (NMR) spectroscopy. 2H NMR relaxation analysis provided a detailed picture of the mobility of the ZIF-62 linkers, including local restricted librations and a large-amplitude twist; these details were verified by molecular dynamics. A comparison of ZIF-62 crystals and glasses revealed that vitrification does not drastically affect the fast individual flipping motions with large-amplitude twists, whereas it facilitates slow cooperative large-amplitude twist motions with a decrease in the activation barrier. These observations support the findings of previous studies, indicating that glassy ZIF-62 retains permanent porosity and that short-range disorder exists in the alignment of ligands because of distortion of the coordination angle.

Stroboscopy and acoustic analysis of voice following endotracheal intubation in otological surgeries

BackgroundStroboscopy is an endoscopy that is performed with intermittent light at a frequency that approximates the frequency of a moving object so that it appears in slow motion or motionless. It is used to analyze the structure and motion of the vocal fold.Aim and objectiveTo compare the stroboscopic findings of various vocal parameters such as symmetry, amplitude, periodicity, mucosal wave of vocal folds, and glottis closure before and after elective endotracheal intubation and to compare acoustic analysis of voice using fundamental frequency, intensity, maximum phonation time, and dysphonia severity index in patients before and after elective intubation, who were undergoing otological surgeries. It also assesses the correlation between changes in these vocal and acoustic parameters and the size of the endotracheal tube, duration of intubation, and number of attempts made during intubation. This study creates awareness and provides insights to avoid intubation-related vocal fold injury.MethodsThis was a prospective cohort study involving 31 patients done in a Tertiary Care Centre. All patients who underwent otological surgeries by elective endotracheal intubation were included. All of them underwent stroboscopic and acoustic evaluation preoperatively, 24 h, and 7 days postoperatively.ResultsStatistically significant changes in mucosal wave pattern score were observed in the 1st postoperative day that reverted to normal by the end of 7th postoperative day and in GRBAS which was significant at the end of both 1st and 7th POD. Other parameters like fundamental frequency, intensity, DSI, MPT, amplitude, symmetry, periodicity, and glottis closure remain unaltered. There was a moderate positive correlation between the duration of intubation (minutes) and mucosal wave 1st POD (P-value: 0.003).ConclusionThe majority of the patients (61%) had normal laryngeal structures. A total of 39% had evidence of injury, the most common being right vocal fold hemorrhage improved by the end of 7th postoperative day and became normal.

Once and Again: Repeated Viewing Affects Judgments of Spontaneity and Preparation

Reality is fleeting, and any moment can only be experienced once. Rewatching a video, however, allows people to repeatedly observe the exact same moment. We propose that people may fail to fully distinguish between merely observing behavior again (through replay) from that behavior being performed again in the exact same way. Using an assortment of stimuli that included auditions, commercials, and potential trial evidence, we demonstrated through nine experiments (N = 10,412 adults in the United States) that rewatching makes a recorded behavior appear more rehearsed and less spontaneous, as if the actors were simply precisely repeating their actions. These findings contribute to an emerging literature showing that incidental video features, like perspective or slow motion, can meaningfully change evaluations. Replay may inadvertently shape judgments in both mundane and consequential contexts. To understand how a video will influence its viewer, one will need to consider not only its content, but also how often it is viewed.

AC-Modulated XPS Enables to Externally Control the Electrical Field Distributions on Metal Electrode/Ionic Liquid Devices.

X-Ray Photoelectron Spectroscopy (XPS) has been utilized to extract local electrical potential profiles by recording core-level binding energy shifts upon application of the AC [square-wave (SQW)] bias with different frequencies. An electrochemical system consisting of a coplanar capacitor with a polyethylene membrane (PEM) coated with the Ionic Liquid (IL) N,N-diethyl-N-methyl-N-(2-methoxyethyl) ammonium bis(trifluoromethanesulfonyl)imide (DEME-TFSI) as the electrolyte is investigated. Analyses are carried out in operando, such that XPS measurements are recorded simultaneously with current measurements. ILs have complex charging/discharging processes, in addition to the formation of Electrical Double Layers (EDL) at the interfaces, and certain properties of these processes can be captured using AC modulation within appropriate time windows of observation. Herein, we select two frequencies, namely, 10 kHz and 0.1 Hz, to separate effects of the fast polarization and slow migratory motions, respectively. Moreover, the local potential developments after adding two equivalent series resistors at three different physical positions of the device have been carefully evaluated from the binding energy shifts in the F 1s peak representing the anion of the IL. This circuit modification allows us to quantify the AC currents passing through the device, as well as the system's impedance, in addition to revealing the potential variations due the IR drops. The complex AC-modulated local XPS data recorded can also be faithfully reproduced using the unmodulated F 1s spectrum and by convoluting it with electrical circuit output provided by the LT-Spice software. The outcome of these efforts is a more realistic equivalent circuit model, which can be related to chemical/physical makeup of the electrochemical system. An important finding of this methodology emerges as the possibility to induce additional local electrical field developments within the device, the directions of which can be reversed controllably.

Competition between indigo carmine and water in the formation of dynamics behavior at different temperatures

We apply molecular dynamics methods to determine the impact of temperature on the structural and dynamic properties of aqueous solution of indigo carmine at temperatures between 300 and 323 К. We report that indigo carmine motion changes from the sub-diffuse to the diffuse regime at t = 100 ps, while water molecules continue to move in the slowed sub-diffuse regime. We demonstrate that the determining factor in the change of the structural and dynamic properties of the aqueous solution of indigo carmine at temperatures between 300 and 323 K is the change in the local structure of water and that the presence of indigo carmine leads to the decrease in temperatures at which a slowed motion of solution components is observed.

DETERMINATION OF GRAVITY COAL SHOOT GEOMETRICS FOR A COAL MINE

This article presents the results of scientific research carried out by the authors in the field of transportation technology in industrial transport. The application of a gravity coal intake device designed to lower coal from the upper horizon to the averaging warehouse of the lower horizon of a coal mine is considered. The velocities of the uniform movement of the load along the gravitational angle are determined depending on the angle of inclination. The numerical integration algorithm is implemented in the software environment of the Scilab application program. The results of calculating the speed of movement from the current value of the descent depth, for the required descent depth of 40 meters and for placement options in various sections of the section at the angles of inclination of the acceleration sections of 30, 40 and 45 degrees are presented. The main geometric parameters of the gravitational coal intake device for a coal mine are determined from the condition of limiting the speeds of coal movement. The design of the gravitational coal intake must be performed based on the condition at the beginning of accelerated movement, then movement at a steady speed and then slow motion to the required speed of coal exit from the coal intake at the required speed of 2 m/sec. The presented research results allowed us to determine the main parameters of the gravitational device (coal intake) proposed for use in the cyclic flow scheme of the «Molodezhny» coal mine of «Kazakhmys Corporation» LLP. Keywords: coal mine, cyclic flow technology, coal transportation, gravity device, coal intake.

Tuning limit cycles with a noise: Survival and collapse.

We consider a general class of limit cycle oscillators driven by an additive Gaussian white noise. Based on the separation of timescales, we construct the equationof motion for slow dynamics after appropriate averaging over the fast motion. The equationfor slow motion whose coefficients are modified by noise characteristics is solved to obtain the analytic solution in the long time limit. We show that with increase of noise strength, the loop area of the limit cycle decreases until a critical value is reached, beyond which the limit cycle collapses. We determine the noise threshold from the condition for removal of secular divergence of the perturbation series and work out two explicit examples of Van der Pol and Duffing-Van der Pol oscillators for corroboration between the theory and numerics.

Income Inequality and External Wealth of Nations

Abstract We study the relationship between income inequality and external wealth using dynamic panel data models with 5-years average observations to consider the slow motion of available data in the case of 88 emerging and developing economies for the period 1970–2020. We find evidence of a significant positive association between inequality indicators and net external wealth. This relationship is statistically significant for all income inequality measures and net external wealth variables. If the Top 1 of the richest individuals in a given country increments their share by 1 % point this will produce an average same-year increment in net foreign assets of 0.45 % in terms of the country’s GDP. The long-run effect is more than double in magnitude (1.05 % of GDP). For the Top 10, the long-run effect increases tenfold (11.6 % of GDP). When disaggregated into foreign assets and liabilities, we find a heterogeneous behavior of the financial elites. These findings reveal that financialized elites have a greater propensity to accumulate external wealth than the rest of the population.