Amplitude Values Research Articles

Evaluation of Peripheral Circulatory Changes Following Hydrotherapy and Controlled Physical Training in Patients with Atherosclerotic Lower Limb Ischemia

Numerous studies highlight the significant role of exercise therapy in patients with peripheral artery disease (PAD), emphasizing how regular physical exercise enhances vascular endothelial function and promotes metabolic adaptations in skeletal muscles, ultimately improving walking performance. There are currently discussions in the medical world on optimizing noninvasive therapy to prevent the development of lower limb ischemia. This study aimed to assess the impact of a supervised training program combined with whirlpool massage treatment on improving peripheral circulation and physical performance in patients suffering from peripheral artery disease. Methods: One hundred participants (both male and female) aged between 39 and 79 years old (60.0 ± 11.6) were included in the analysis, all diagnosed with peripheral circulation disorders. The participants were assigned to two groups. The study group received 10 whirlpool treatments of the lower limbs and a personalized training program. The control group only participated in the training sessions. Pre- and post-intervention evaluations included impedance plethysmography and the six-minute walk test (6MWT). Results: Assessing the results of local flow parameters, after the procedures, a statistically significant increase in the pulse wave amplitude (PAmpl, p < 0.001) and systolic slope (PSlope, p < 0.001) values was found, as well as a statistically significant decrease in the crest time (CT, p < 0.001) and propagation time (PT, p = 0.007) values in the study group, which indicates an improvement in blood flow in the peripheral circulation. Also, in the 6 min walk test, a statistically significant increase in the walking distance was noted in the study group after the procedures. Conclusions: Physical training, combined with whirlpool massage treatment, has a beneficial effect on improving peripheral blood flow assessed by impedance plethysmography, as well as patients’ tolerance to physical exercise. The inclusion of hydrotherapy as part of cardiovascular rehabilitation protocols in patients with peripheral ischemia is a promising form of conservative treatment.

Prototype of small-scale test machine for vibration measurement on bearings

Repetitive movements of shaft in bearings over time intervals generate vibrations. The aim of this research is to build the prototype of small scale of machine to measure the vibration values of bearing due to spinning shaft using an accelerometer and Arduino sensor device. The method used is to build a device of miniature rotating machines which was used to simulate machine vibrations. The ADXL345 accelerometer measured the magnitudes of vibration that occurs on the rotating shaft. Arduino Uno analyzed data from ADXL345. The amplitude, speed, acceleration and frequency values were measured according to rotation values. It was found the largest amplitude, speed, acceleration and frequency values were obtained at the radial point Y1 position.

Reliability of MScanFit Motor Unit Number Estimation in the Trapezius Muscle.

MScanFit motor unit number estimation (MUNE) is the most recent MUNE method which has shown promising results in extremity muscles, but it has not been applied to bulbar muscles. Bulbar muscles are particularly important in the diagnosis of amyotrophic lateral sclerosis (ALS). This study aimed to investigate the feasibility and reliability of MScanFit MUNE in the accessory nerve and trapezius muscles. A total of twenty healthy participants were examined twice within 1-2 weeks. We extracted the MScanFit MUNE and size parameter, and compound muscle action potential (CMAP) amplitude values. The reliability of these parameters was assessed using the intra-rater coefficient of variation (CoV), intraclass correlation coefficient (ICC), and Bland-Altman plots. We also correlated MUNE values with CMAP amplitudes using correlation coefficients. Mean MUNE values (Day 1 = 132.1 and Day 2 = 137.4), CMAP amplitudes (Day 1 = 9.71 mV and Day 2 = 10.10 mV) and size parameters did not differ between the two sessions (p > 0.05). CoV showed excellent reliability for MUNE values, size parameters, and CMAP amplitudes (CoV < 7%) whereas ICCs showed moderate reliability for MUNE values (ICC = 0.619), poor to moderate reliability for size parameters (between 0.393 and 0.689), and good reliability for CMAP amplitude (ICC = 0.864) There was no correlation between MUNE values and CMAP amplitudes. MScanFit MUNE is applicable and mostly reliable in the trapezius muscle. Further studies in patients are needed to investigate the sensitivity of MScanFit in this muscle in detecting motor unit loss, particularly in ALS.

Evaluation of water distribution and uniformity of sprinkler irrigation based on harmonic analysis and finite element method

A model that describes the water distribution of a single fixed spray plate sprinkler (FSPS) based on the harmonic analysis was proposed. The relationship between the pressure head, nozzle diameter, mean sprinkler irrigation depth, and amplitude was established. An analytical model for evaluating the sprinkler irrigation uniformity coefficient of a multi-sprinkler combination was developed by introducing a weighting coefficient. In conjunction with the sprinkler irrigation system's finite element hydraulic calculation model, the impact of the pipe diameter, sprinkler number, and sprinkler spacing on system energy loss, pressure head, and sprinkler irrigation system uniformity was assessed. The results demonstrated that under varying pressures and nozzle diameters, the Camargo and Sentelhas coefficient (c) between the measured and fitted mean value of the sprinkler irrigation depth of a single FSPS was greater than 0.99, while the c between the measured and fitted amplitude value was approximately 0.93. Under different combinations of nozzle, pressure head, and sprinkler spacings, the measured, derived, and calculated values of 54 sprinkler irrigation uniformity combinations were basically consistent. The uniformity of the combined FSPS under a linear-move sprinkler system was significantly affected by nozzle diameter, pipe diameter, sprinkler spacing, and inlet pressure head at 0.01 level. The number of sprinklers also had a significant impact at 0.05 level. The findings of this study could serve as a theoretical foundation for the proper design of linear-move sprinkler irrigation systems.

Numerical analysis and optimization of natural convection heat transfer in inclined square cavities with sinusoidal heating elements

Abstract This study presents a numerical analysis of natural convection heat transfer within inclined square cavities featuring sinusoidal heating elements. The analysis, conducted using a finite volume approach implemented in ANSYS 16.0, aims to estimate flow and heat regimes under steady-state conditions. Grid-independent analyses were performed to ensure numerical accuracy. The vertical walls of the enclosure were maintained at a cold temperature, while the other two walls were perfectly insulated. Key parameters investigated include Rayleigh numbers (104, 105, 106), corrugation numbers (3, 5, and 7), amplitude values (0.1, 0.3 and 0.5), and enclosure inclination angles (δ = 0°, 15°, 30°, 45°, 60°, 75°). The sinusoidal element’s diameter to enclosure length ratio was set at 0.4, and fluid properties were assumed constant with a Prandtl number of 7.0. Results were illustrated using isothermal and flow lines, with heat transfer discussed in terms of local and average Nusselt numbers. Findings indicate that at Ra = 106, local Nusselt numbers exhibited a sinusoidal distribution influenced by corrugation and amplitude, with a 50% increase in local Nusselt number as amplitude increased from 0.1 to 0.5. Average Nusselt number enhancements were observed with higher corrugation numbers and wave amplitudes, while the number and size of eddies were sensitive to Rayleigh numbers. Enclosure inclination significantly affected the formation of vortices, particularly at angles of 60° and 75°.

Automated interferometric stand for determination of amplitude-frequency characteristics of acoustic emitters

An automated interferometric stand (AIS) was created to determine the amplitude-frequency characteristics of acoustic emitters in the range from 0.5 to 200 kHz. The created AIS contains a unit for generating acoustic sinusoidal excitation pulse packets and a recording unit. The unit for generating acoustic pulse packets includes a generator of sinusoidal signals, a microprocessor unit for pulse packets generation and the AIS synchronization, a power amplifier of a sinusoidal signal to create a sufficient power of the acoustic emitter excitation signal. The recording unit includes a Michelson interferometer with a sound-conducting rod in one of the arms. One of the ends of the rod has a mirror surface. The other end is connected to the acoustic emitter through an acoustic contact. The length of the sound-conducting rod is 50 cm, which is enough to ensure measurements at the lower limit of the frequency range of the acoustic emitter radiation. The propagation time of the acoustic wave in the rod is of the order of 75 microseconds. As the end of the rod vibrates due to acoustic excitation, the initial path difference of the optical beams in the interferometer will change, causing a change in the intensity of the illumination produced by the interfering beams. These changes are recorded by photodiode in the other arm of the interferometer. After the photodiode signal is amplified in the amplifier, it is fed to the analog-to-digital converter, the output of which is transferred to the buffer memory, where the discretized values of the response signal amplitude during the time of the measuring pulse are accumulated. The control algorithm of the AIS is carried out with the help of developed software. The results of measuring the amplitude-frequency characteristics of mass-produced broadband acoustic emitters using AIS proved the satisfactory convergence of the obtained frequency responses with the passport data of these serial devices frequency responses. The amplitude-frequency characteristic of experimental sample of a piezoelectric acoustic emitter, made for research on the detection and identification of internal defects in laminated composite structures and "composite-concrete" adhesive joints, was obtained.

Librations and obliquity of the largest moons of Uranus

Following the discovery of several ocean worlds in the solar system, and the selection of Uranus as the highest priority objective by the Planetary Science and Astrobiology Decadal Survey 2023-2032, the five largest moons of Uranus (Miranda, Ariel, Umbriel, Titania and Oberon) have been receiving renewed attention as they may also harbor a subsurface ocean. We assess how rotation measurements could help confirm the internal differentiation of the bodies and detect internal oceans if any. Because of the time-varying gravitational torque of Uranus on the flattened shape of its synchronous satellites, the latter librate with respect to their mean rotation and precess with a non zero obliquity. For a range of interior models with a rocky core surrounded by a hydrosphere, either solid or divided into an outer ice shell with a liquid ocean underneath, we compute their diurnal libration amplitude and obliquity. We find that if the Uranian satellites were two-layer solid bodies, libration measurement accuracies from around 0.25 m for Oberon to around 6 m for Miranda would rule out the possibility of homogeneous interiors. In combination with independent estimates of the mean moment of inertia (MOI), libration measurements could also be used to detect the presence of an ocean, the measurement precision required for this depending on the actual value of the libration amplitude. To compute the obliquity, we first build series for the orbital precession of all five satellites with a secular perturbations model. With the exception of Miranda, we show that due to the mutual gravitational interactions between the satellites, the obliquity of the large Uranian moons exhibits relatively large periodic variations around the mean value. We find that an obliquity measurement accuracy from around 1 m for Ariel to around 400 m for Oberon can rule out the homogeneous case. The presence of an internal global ocean could allow a resonant amplification of the obliquity, facilitating its detection. If no such resonance occurs, the obliquity would be almost indistinguishable from that expected for a solid body. The effect of tidal deformations on the rotation of the small to medium-sized Uranian moons is showed to be limited. Librations would be reduced by up to 10% and obliquity increased by up to 15% for Titania and Oberon, the effects being negligible for Miranda.

Research on the effect of grinding force on the axial ultrasonic vibration-assisted grinding of Ti-6Al-4V with multi-grain conical grinding head

A multi-grain conical grinding head capable of performing both peripheral and end-face grinding was created in Abaqus to simulate conventional grinding (CG) and axial ultrasonic-assisted vibration grinding (AUVAG) on Ti-6Al-4V alloy. A comparative analysis was conducted to examine the effects of key grinding parameters on the fluctuation amplitude and mean value of grinding forces in CG and AUVAG. The mechanism of ultrasonic vibration’s influence on grinding forces was analyzed, and a theoretical model for normal and tangential grinding forces in peripheral grinding of Ti-6Al-4V was established. Additionally, the surface morphology of CG and AUVAG was analyzed. The study found that the fluctuation amplitude of grinding forces in both AUVAG and CG increases with the axial grinding depth, feed rate, ultrasonic amplitude, and ultrasonic frequency, while it decreases with increasing spindle speed. However, the fluctuation amplitude in AUVAG is greater than that in CG. The average grinding forces in both CG and AUVAG increase with the grinding depth and feed rate, and decrease with the spindle speed. Compared to CG, the mean F x ([Formula: see text]) and F y ([Formula: see text]) are lower in AUVAG, while the mean F z ([Formula: see text]) is higher. Under different axial grinding depths, the maximum reduction in [Formula: see text] and [Formula: see text] for AUVAG is 4.70% and 5.18%, respectively, while the maximum increase in [Formula: see text] is 77.48%. At different feed rates, the maximum reduction in [Formula: see text] and [Formula: see text] for AUVAG is 3.02% and 21.01%, respectively, while the maximum increase in [Formula: see text] is 81.67%. Under different spindle speeds, the maximum reduction in [Formula: see text] and [Formula: see text] is 7.20% and 17.82%, respectively, and the maximum increase in [Formula: see text] is 281%. As the ultrasonic amplitude and frequency increase, [Formula: see text] significantly rises, but the effect on [Formula: see text] and [Formula: see text] is weak. AUVAG improves the surface quality of the specimen.

The Effect of Different Adaptation Formulas on Mid-Latency Auditory Evoked Potentials in Adults with Hearing Aids.

We were conducting this study to evaluate the effects of different hearing aid adaptation formulas on middle latency responses (MLR) in adult hearing aid users. The study included 72 participants: those with moderate hearing loss using hearing aids with two different formulas for the last year, those with moderate hearing loss not using hearing aids, and those without hearing loss. Sixteen participants using NAL-NL1 and NAL-RP formulas were Group 1; twenty using NAL-NL2 and DSL formulas were Group 2; fifteen with hearing loss not using devices were Group 3; and twenty-one without hearing loss were Group 4. We obtained and compared MLR responses, including Na latency, Pa latency, and Na-Pa amplitude. Group 1 mean Na-Pa amplitude value was found to be higher than Group 2 (p = 0.001). No significant difference was observed between Group 1 and Group 2 in terms of Na latency and Pa latency values (p = 0.001; p = 0.035). It was observed that the mean Na-Pa amplitude values in Group 1 and Group 2 were higher than Group 3 (p = 0.001), but this elevation reached the level of statistical significance only in Group 1. No difference was observed between Group 1, Group 2, and Group 3 in terms of Na latency and Pa latency values (p = 0.001; p = 0.035). Compared with those without hearing loss (Group 4), participants with hearing loss (Group 1, Group 2, and Group 3) had longer Na latency and Pa latency values (p = 0.001; p = 0.035), and Na-Pa amplitudes were lower (p = 0.001). The effect of current (tested) hearing aid usage time on Na latency, Pa latency, and Na-Pa amplitude values of Group 1 and Group 2 was not observed. In all groups, there was a positive correlation between audiometric airway/bone conduction pure tone averages and speech acquisition threshold values, Na latency and Pa latency values, and a negative correlation between Na-Pa amplitude values. In all groups, there was a negative correlation between speech discrimination scores and Na and Pa latency values, as well as a positive correlation between Na and Pa amplitude values. There was a positive correlation between age and Pa latency values in all groups, as well as a negative correlation between Na and Pa amplitude values. Middle latency responses are affected by the presence of hearing loss, the use of hearing aids, and different hearing aid adaptation formulas. MLR measurements with a hearing aid can be used as an objective test to evaluate the benefit of hearing aid use.

Dynamic Analysis and Vibration Control of Additively Manufactured Thin-Walled Polylactic Acid Polymer (PLAP) and PLAP Composite Beam Structures: Numerical Investigation and Experimental Validation.

This study primarily presents a numerical investigation of the dynamic behavior and vibration control in thin-walled, additively manufactured (AM) beam structures, validated through experimental results. Vibration control in thin-walled structures has gained significant attention recently because vibrations can severely affect structural integrity. Therefore, it is necessary to minimize these vibrations or keep them within acceptable limits to ensure the structure's integrity. In this study, the AM beam structures were made of polylactic acid polymer (PLAP), short carbon fiber reinforced in PLAP (SCFR|PLAP), and continuous carbon fiber reinforced in PLAP (CCFR|PLAP), with 0°|0° layer orientations. The finite element modeling (FEM) of the AM beam structures integrated with macro fiber composite (MFC) was carried out in Abaqus. The initial four modal frequencies of bending modes (BMs) and their respective modal shapes were acquired through numerical simulation. It is crucial to highlight the numerical findings that reveal discrepancies in the 1st modal frequencies of the beams, ranging up to 1.5% compared to their respective experimental values. For the 2nd, 3rd, and 4th modal frequencies, the discrepancies are within 10%. Subsequently, frequency response analysis (FRA) was carried out to observe the frequency-dependent vibration amplitude spectrum at the initial four BM frequencies. Despite discrepancy in the amplitude values between the numerical and experimental datasets, there was consistency in the overall amplitude behavior as frequency varied. THz spectroscopy was performed to identify voids or misalignment errors in the actual beam models. Finally, vibration amplitude control using MFC (M8507-P2) was examined in each kinematically excited numerical beam structure. After applying a counterforce with the MFC, the controlled vibration amplitudes for the PLAP, SCFR|PLAP, and CCFR|PLAP configurations were approximately ±19 µm, ±16 µm, and ±13 µm, respectively. The trend in the controlled amplitudes observed in the numerical findings was consistent with the experimental results. The numerical findings of the study reveal valuable insights for estimating trends related to vibration control in AM beam structures.

Arbitrary Waveform Voltage Measuring Converter for Wideband AC Voltmeter

Alternating current (AС) voltage measurement is one of the most common types of measurements in various fields of science and technology. To evaluate the AC voltage level, special voltmeters are used which allow recording of amplitude, average and/or root mean square (RMS) voltage values. Among these measuring instruments, voltmeters of mean square voltage are especially significant because RMS is a fundamental physical characteristic of an electrical signal and is a true measure of power. The wide distribution of non-sinusoidal signals necessitates the creation of voltmeters for direct measurement of RMS. The main component of such voltmeter is an AC voltage to direct current (DC) voltage measuring converter based on the root-mean-square value level (AC RMS-DC converter). An analysis of existing technical solutions shows that it is advisable to use a thermoelectric converter (TEC) for high-precision measurement of RMS voltage of an arbitrary shape with a spectrum in the frequency band from 20 Hz to 20–50 MHz. Such a AC RMS-DC converter must contain a differential semiconductor TEC and an input broadband voltage amplifier with low nonlinearity of the frequency response. The aim of the paper was to develop a measuring AC RMS-DC converter of arbitrary shape voltage in which special attention is paid to modernization of the TEC and reduction of the AC RMS-DC converter error using corection of the frequency response of the input amplifier and introduction automatic calibration of the output voltage. Features of semiconductor chips and design of TEC in the form of a microcircuit or microassembly, results of converter’s and TEC elements’ parameters measurements are presented. A significant influence of the frequency response of the input amplifier and the offset voltage of the TEC transistors on the AC RMS-DC converter error was noted. Modernization of the input amplifier and introduction of automatic calibration of the output voltage ensured an error in a sinusoidal signal converting of less than 1 % in the range from 20 Hz to 50 MHz.

Reliability of sEMG data of back muscles during static submaximal loading situations − Values and pitfalls

Alterations of trunk muscle activity can be objectified using surface electromyography (sEMG). But for diagnostic purposes reliable reference values are needed. Therefore, the present study evaluated sEMG measurements of representative back muscles concerning their reliability.For this purpose, 49 healthy individuals (24 women) were subjected to static loads with defined portions of their upper body weight by applying whole-body tilts up to 90° in upright posture. Reliability analyses were carried out for amplitude values and normalized values according 90° tilt angle. Reliability measures included intraclass correlation coefficient (ICC), standard error of measurement (SEm), standard error of the mean (SEM), and coefficient of variation of method errors (CVME).ICC values for the amplitude values were > 0.79 for M. multifidus (MF) and M. longissimus (LO). For the normalized values, distinctively lower ICC levels were generally detected (0.33–0.81). The values of SEm and SEM also increased with increasing load, while CVME levels of the amplitude values maintained similar levels.For defined static extension loads, good to excellent reliability can be demonstrated for back muscles. The established normative values for SEm, SEM and CVME parameters may be used for diagnostic purposes during defined submaximal load situations. This does not apply to normalized data.

Geological position, structural manifestations of the Elbistan earthquake and tectonic comparison of two strongest seismic events 06.02.2023 in Eastern Türkiye

The Elbistan (Ҫardak) earthquake with magnitude Mw = 7.5 or 7.6 happened in Eastern Anatolia on 06.02.2023 at 10:24 UTC, following the strongest in the region of East Anatolian (Pazarçik) earthquake with Mw = 7.8 which occurred on the same day at 1:17 UTC to the south of the region. The Elbistan earthquake activated adjacent segments of the Ҫardak and Uluova faults with Quaternary left-lateral strike-slip displacements. The resulting seismic ruptures have a total length of 190 km, of which 148 km are represented by sinistral lateral slip. Their maximum amplitude of 7.84 m was recorded 8 km east of the epicenter. The strike-slip seismic ruptures of the Elbistan and East Anatolian earthquakes represent exposure of their focal zones on the land surface. Both earthquakes exceed average values of these parameters for continental earthquakes of strike-slip type in terms of focal zone sizes and amplitudes of seismic displacements. At the same time, both sources do not propagate deeper than the upper part of the crust (16–20 km). Ophiolite complexes covering the same depths are widely spread in the area of focal zones of both earthquakes. Two maxima were found in the distribution of seismic strike-slip displacement along the epicentral zone of the Elbistan earthquake (i) amplitudes of 5.7–7.84 m in the Ҫardak fault zone and (ii) amplitudes of 3.5–5.1 m in the Uluova fault zone. Both maxima coincide to the areas of ophiolites or their contacts with basement rocks. In crystalline basement rocks, the sinistral strike-slip amplitudes are significantly reduced. We attribute the increased values of focal zone sizes and displacement amplitudes of both earthquakes to the rheological features of ophiolites, which increase a possibility of slip of rocks during seismic movements. We explain the fact that the sources of both earthquakes cover only the upper part of the crust, by the uplift of the top of rocks with reduced P-wave velocities, including the upper mantle and the lower part of the crust and interpreted as heated rocks with reduced strength.

Multiple solutions and orbit change in energy harvesting system with a flag configuration

AbstractThe aim of this paper is to present a methodology for implementing the high-energy orbits which is still an open problem for nonlinear energy harvesters. To achieve it, this paper presents a new design of system with a flag configuration which potential function is shaped with the use of elastic elements. We have identified the lift force in FEM for wide spectrum of air velocities and used it as excitation in dimensionless mathematical model. On this basis we have conducted simulations of energy harvesting effectiveness. In the second part of the work, we focused on identifying the coexisting solutions. Due to the existence of high-energy orbits and low-energy orbits, we conducted simulations to investigate the possibility of changing the orbit. We used the Impulse Excitation Diagram here, but supplemented it with multi-colored probability distribution maps illustrating the possibility of achieving a stable orbit at given numerical values of the impulse amplitude and duration for various values of air flow velocity. The use of probability distribution maps allow to select the optimal impulse characteristics from the point of view of the energy necessary for its initiation.

Sensor concepts for gear damage detection in wind power drives

Abstract Gearbox failure in offshore wind turbines can be caused by fatigue damages like tooth fank fracture (TFF) or pitting damage. For damage detection in current applications, simple threshold values for vibration amplitudes are used to initiate a shutdown of the wind turbine. At this time significant damage to the gear is already present and an external maintenance is inevitable. The objective of this experimental study is to determine a better sensor concept for detection of gear damage in wind power drives during operation. The damage needs to be detected at a very early stage before the health condition of the gears becomes critical. Evaluation criteria for comparison of sensor concepts include the earliest possible detection of damage, robust and reliable detection under varying operating conditions, as well as practicality and cost-effectiveness. The test results show, vibration measurement in radial direction and in high frequency ranges is most suitable and most robust for pitting detection during operation. With the best sensor concept in place, it is possible to detect gear damage like pitting at a very early stage of 0.3 % pitting size.

Numerical investigation on transonic flutter characteristics of an airfoil with split drag rudder

In this paper, a series of flutter simulations are carried out to investigate the effects of split drag rudder (SDR) on the transonic flutter characteristic of rigid NACA 64A010. A structural dynamic model addressing two-degree-of-freedom pitch-plunge aeroelastic oscillations was coupled with the unsteady Reynolds-averaged Navier-Stokes equations to perform flutter simulation. Meanwhile, the influence mechanism of SDR on flutter boundary is explained through aerodynamic work and the correlated shock wave location. The results show that the SDR delays the shock wave shifting downstream, and the Mach number corresponding to reaching freeze region increases as the split angle increases. Therefore, the peak value of aerodynamic moment coefficient amplitude and the sharp ascent process of phase occurs at higher Mach number, which leads to the delay in the occurrence of the transonic dip. Besides, before the transonic dip of airfoil without SDR occurs, the aerodynamic moment phase of airfoil with the SDR decreases slowly due to the decrease in the speed of shock wave moving downstream. This results in an increased flutter speed when employing the SDR before the transonic dip of airfoil without SDR occurs. Meanwhile, the effects of asymmetric split angles on the transonic flutter characteristics are also investigated. Before the transonic dip of airfoil without SDR occurs, the flutter characteristic is dominated by the smaller split angle.

Upregulation of NGF/TrkA-Related Proteins in Dorsal Root Ganglion of Paclitaxel-Induced Peripheral Neuropathy Animal Model.

Paclitaxel (PTX) can induce chemotherapy-induced peripheral neuropathy (CIPN) as a side effect. The aim of this study was to understand the neurochemical changes induced by NGF/TrkA signaling in PTX-induced neuropathic pain. The PTX-induced CIPN mouse model was evaluated using nerve conduction velocity (NCV) and behavioral tests. Protein expression in mouse DRG was observed by Western blotting and immunohistochemistry. Nerve growth factor (NGF), IL-6, and IL-1β mRNA levels were determined using qRT-PCR by isolating total RNA from whole blood. PTX showed low amplitude and high latency values in NCV in mice, and induced cold allodynia and thermal hyperalgesia in behavioral assessment. Activating transcription factor 3 (ATF3) and MAPK pathway related proteins (ERK1/2), tropomyosin receptor kinase A (TrkA), calcitonin gene related peptide (CGRP) and transient receptor potential vanilloid 1 (TRPV1) were upregulated 7th and 14th days after 2 mg/kg and 10 mg/kg of PTX administration. Protein kinase C (PKC) was upregulated 7th days after 10 mg/kg PTX treatment and 14th days after 2 mg/kg and 10 mg/kg PTX administration. NGF, IL-6, and IL-1β fold change values also showed a time- and dose-dependent increase. Taken together, our findings may improve our understanding of the nociceptive symptoms associated with PTX-induced neuropathic pain and lead to the development of new treatments for peripheral neuropathy.

Effective methods for quantifying complexity based on improved ordinal partition networks: Topological dispersion entropy and weighted topological dispersion entropy

Topological permutation entropy is based on ordinal partition networks (OPNs) to approximate topological entropy of low-dimensional chaotic systems. But the ordinal patterns of OPN ignore the magnitude of the amplitude value. To solve the problem, we propose topological dispersion entropy (TDE) and weighted topological dispersion entropy (WTDE) based on dispersion patterns to characterize the complexity of a system. Furthermore, WTDE strengthens the topological structure analysis of complex networks by weighting the adjacency matrix of the improved ordinal partition networks, thereby more accurately capturing the dynamic evolution of time series. The proposed methods are comprehensively evaluated by numerical experiments. The results show that the performance of both TDE and WTDE is significantly better than TPE. Especially, WTDE has good stability to parameters, data length, and noise. Finally, combining support vector machines and K-Nearest Neighbor, TDE and WTDE are applied to the classification of physiological data and mechanical failure data.

Experimental study on thermally induced vibration of flexible solar cell wing simulator

Abstract With the development of large spacecraft and satellite payloads, the power supply required is increasing, especially in space solar power stations, and the large flexible solar wing is an inevitable trend in the future. Due to their light weight and large area, flexible solar wings may face thermally induced vibration during orbit operation, which will lead to the degradation of spacecraft performance and even structural damage. In this paper, the test method of a flexible solar wing simulator is established, and the thermally induced vibration test of a flexible solar cell wing simulator is carried out. And vibration amplitude value is 25 and 9 microns with a frequency 0.56Hz.The characteristic of thermally induced vibration of flexible solar cell wing is given, which provides a basis for its thermally induced vibration suppression.

Identifying the parameters and operation modes of the cavitation apparatus taking into account the influence of the processing material

The object of this study is dynamic pressure that takes into account the main parameters of technological process. Under real conditions of cavitation apparatus operation, a discrepancy between actual and calculated parameters of 30–50 % was found, which significantly reduces the efficiency and quality of material processing. The problem was solved through a joint study of the movement of the acoustic apparatus and the technological environment as a single structured system taking into account the influence of materials. This is a peculiarity of the approach and distinctive features of the results in comparison with existing ones, in which the research was conducted separately for the processing material and the cavitation apparatus. The model proposed in the work reflects the elastic, inertial, and dissipative parameters in the equations of motion, provided that their changes are taken into account, both in the acoustic apparatus and in the technological material. This approach has made it possible to reveal the physical essence of the interaction and analytically describe their joint movement. The resulting analytical dependences made it possible to calculate and propose numerical values of vibration amplitudes in the range of 4.0...20.0 μm, sound pressure values in the range of 5.0...30.0∙105 Pa for media with a viscosity of (10–200)∙10-3 Pa∙s. With the set value of the amplitude, it is possible to assign the necessary parameters for the implementation of the cavitation process. The developed calculation algorithm ensures the reliability of the accepted models and parameters of the cavitation apparatus. The proposed approach of joint study of the movement of the acoustic apparatus and the environment is expedient to use for the practical implementation of ultrasonic treatment. In particular, such processes as dispersion, emulsification, mixing, extraction, and others, in order to increase their efficiency