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Cold plasma is a novel nonthermal technology that has been used for preserving and maintaining the quality of food materials. Researchers developed numerous cold plasma equipment to study the effect of plasma on food materials; however, the degree of processing such as flow of plasma species from the source of plasma to the food material and their interaction/diffusion into the food, differs with respect to the equipment. The computational study can simulate the flow dynamics of plasma which in turn can improve the efficiency of processing and design aspects. Computational fluid dynamics (CFD) is the most reliable, cost-effective, and robust numerical tool used for simulating various high-end food processing technologies. In cold plasma processing, computational study aids in revealing the distribution of reactive species and their flow dynamics on the target surface. As CFD studies on plasma interaction with food materials are not available, this review is focused on covering the basics of using CFD in cold plasma simulation. It also explores the significant use of CFD in cold plasma simulation in various sectors along with its possible and futuristic applications in food processing.

A mathematical model of a spacecraft (SC) with an arbitrary number of large flexible structural (appendages) elements (LFSEs) is developed, implemented, and verified. The SC model obtained based on the general equations of dynamics is written in generalized coordinates. It allows three types of articulation between the LFSEs and the SC’s body: cantilever, and with the help of one-step and two-step hinges. Due to the procedure used in the derivation of the equations of motion, the proposed model allows us to change the number of LFSEs and types of articulation without rewriting the equations of motion in symbolic form, which makes it comfortable for software implementation.

In the present study, the dynamics of the tendon system of a tension-leg platform (TLP) is investigated through the absolute nodal coordinate formulation (ANCF). Based on the energy conversion principle, the stiffness, generalized elastic force, external load and mass matrices of the element are deduced to perform the element assembling by using the finite element method. Then the motion equation of the tendon/riser is established. In this study, the TLP in the International Ship Structures Committee (ISSC) model under the first and second wave forces is considered as the case study. The simulation is performed in the MATLAB environment. Moreover, the accuracy and reliability of the programs are verified for cases of beam model with theoretical solutions. It is found that the motion response of tendons is affected by the TLP movement and environmental load, simultaneously. Then, the motion response is calculated using the SESAM software and exported as the boundary of ANCF tendons. Finally, the static and dynamic characteristics of the four tendons of ISSC TLP are analyzed systematically by the ANCF method. Performed analysis proves the effectiveness and feasibility of the ANCF method. It is concluded that the proposed method is a powerful scheme for calculating the dynamics of tendon/riser in the field of ocean engineering.

New experimental and clinical findings question the historic view of hydrocephalus and its 100-year-old classification. In particular, real-time magnetic resonance imaging (MRI) evaluation of cerebrospinal fluid (CSF) flow and detailed insights into brain water regulation on the molecular scale indicate the existence of at least three main mechanisms that determine the dynamics of neurofluids: (1) inspiration is a major driving force; (2) adequate filling of brain ventricles by balanced CSF upsurge is sensed by cilia; and (3) the perivascular glial network connects the ependymal surface to the pericapillary Virchow–Robin spaces. Hitherto, these aspects have not been considered a common physiologic framework, improving knowledge and therapy for severe disorders of normal-pressure and posthemorrhagic hydrocephalus, spontaneous intracranial hypotension, and spaceflight disease.

This paper presents the results of theoretical studies on rocket/space hardware aerogas dynamics obtained from 2016 to 2020 at the Department of Aerogas Dynamics and Technical Systems Dynamics of the Institute of Technical Mechanics of the National Academy of Sciences of Ukraine and the State Space Agency of Ukraine along the following lines: rocket aerodynamics, mathematical simulation of the aerogas thermodynamics of a supersonic ramjet vehicle, jet flows, and the hydraulic gas dynamics of low-thrust control jet engines. As to rocket aerodynamics, computational methods and programs (CMPs) were developed to calculate supersonic flow past finned rockets. The chief advantage of the CMPs developed is computational promptness and ease of adding wings and control and stabilization elements to rocket configurations. A mathematical simulation of the aerogas thermodynamics of a supersonic ramjet vehicle yielded new results, which made it possible to develop a prompt technique for a comprehensive calculation of ramjet duct flows and generalize it to 3D flow past a ramjet vehicle. Based on marching methods, CMPs were developed to simulate ramjet duct flows with account for flow past the airframe upstream of the air inlet, the effect of the combustion product jet on the airframe tail part, and its interaction with a disturbed incident flow. The CMPs developed were recommended for use at the preliminary stage of ramjet component shape selection. For jet flows, CMPs were developed for the marching calculation of turbulent jets of rocket engine combustion products with water injection into the jet body. This made it possible to elucidate the basic mechanisms of the effect of water injection, jet–air mixing, and high-temperature rocket engine jet afterburning in atmospheric oxygen on the flow pattern and the thermogas dynamic and thermalphysic jet parameters. CMPs were developed to simulate the operation of liquid-propellant low-thrust engine systems. They were used in supporting the development and ground firing tryout of Yuzhnoye State Design Office’s radically new system of control jet engines fed from the sustainer engine pipelines of the Cyclone-4M launch vehicle upper stage. The computed results made it possible to increase the informativity of firing test data in flight simulation. The CMPs developed were transferred to Yuzhnoye State Design Office for use in design calculations.

This paper overviews the main research results obtained from 2016 to 2020 at the Department of System Analysis and Control Problems of the Institute of Technical Mechanics of the National Academy of Sciences of Ukraine and the State Space Agency of Ukraine. The overview was prepared using the method of phenomenological analysis. The results of the system analysis of the trends in the use of space technologies in different areas of human activities are presented. Methods of draft space program evaluation and R&D program formation algorithms are discussed. Research results on the dynamics of spacecraft and components thereof are presented. The dynamics of tethered space systems and microsatellites is considered. Consideration is given to the world’s trends in the development of space transportation systems, the features of their development in Ukraine, and the state of the art of the methodological basis of rocket/space hardware design in Ukraine. Recommendations on working out normative documents and lines of their refinement are given. System analysis methods were considered and found their further development as applied to the space sector. A method of structural-parametric identification was developed for the problem of object simulation with a multidimensional output in the class of beta-autoregressive models, in which autoregrassion weight coefficient ratios are determined based on beta-distribution density functions. On principles of the group data handling method, a regularity criterion was constructed and studied for simulation in the class of beta-autoregressive models in conditions of quasi-repeated observations. Investigations were conducted into the analysis, synthesis, and operation optimization of systems of multilevel, intellectual, and network management under uncertainty. Methodological approaches to the development of symbiotic self-contained aerospace and transport systems were elaborated. A new technology was developed for the construction of surrogate models with the use of approaches on the basis of the synergy of subject field methods and cognitive technologies based on general scientific achievements. Part of the research results has found prectuical use at Yuzhnoye State Design Office.

Under the conditions of a chronic methionine diet (daily addition of amino acids to food (0.15 g/100 g) and water (1% solution)) during 2–12 weeks, the dynamics of liver tests, infl ammatory changes in the blood and blood lipids was monitored. It was found that a methionine diet (MD) leads, starting from 4 weeks of MD, to medium hyperhomocysteinemia, an increase in liver enzymes (AsAT – 1.73, AlAT – 1.5 times, p

For a high-speed rail vehicle with gauge-changeable wheelsets, wheel/rail interactions and vehicle dynamics were numerically and experimentally studied within 600 km/h. Matching among four treads, ...

Purpose. To assess the state of the choroid in patients with HLA-B27-associated anterior uveitis without detectable lesions of the macular zone by ophthalmoscopy. Material and methods. 22 patients with HLA-B27-associated acute anterior uveitis without detectable changes in the macular zone by ophthalmoscopy – the main group. Age: 39.02±13.76 years, men – 16 and women – 8. Best corrected visual acuity varied from 0.1 to 0.5 (average 0.3). The level of intraocular pressure according to Maklakov in all eyes varied from 15 to 22 mm Hg. The parameters of paired intact eyes of patients served as a control. The subfoveal choroid thickness (CT) was determined using optical coherence tomography in comparison with paired intact eyes before treatment and 2 weeks after its initiation. Results. The initial values of the CT indexes in the main group varied from 337 to 371 μm, averaging 354±8 μm. This is statistically significantly higher than in intact paired eyes 255±7 μm (from 246 to 268 μm), p

The Maxwell damper model has been adopted in the simulation of railway vehicle dynamics for a long time and became a basic force element in the multi-body dynamics software. The main purpose of this article is to investigate the predictive accuracy of this model for a railway yaw damper in damping characteristics and vehicle stability assessment. To achieve this objective, a simplified physical damper model was developed for comparisons, which is accurate and at the same time presents low computational costs, being able to be adopted in the multi-body dynamics model of a railway vehicle to speed up the numerical simulations. It was suitably validated in the damper rig test, and simulation results for those two damper models were compared with measured data. Results showed that the traditional Maxwell model of this typical yaw damper cannot accurately describe its dynamic behaviors, while the simplified physical model can accurately reproduce the complex behavior of the actual damper system with a high computational efficiency. Comparisons of vehicle dynamics relevant to vehicle stability were then carried out, by integrating the Maxwell model and the simplified physical model presented in this work into a multi-body dynamics model of a high-speed train in China. It was found that the Maxwell model can reproduce the phenomenon of carbody instability accurately if an appropriate value of the dynamic stiffness is set in the Maxwell model. In the simulation of bogie instability, the Maxwell model overestimates the dynamic damping of this typical yaw damper, and as a result it leads to large errors in stability calculations.

This paper presents a physics-based projection framework for the interfacial treatment of spatially and topologically different grids. The formulation proposes the use of constraint type elements, ...

In earlier work, a driver model incorporating sensory dynamics was identified from driving simulator experiments involving random disturbances, random target paths and linear vehicle dynamics. In t...

The aim of the work is to determine the dynamics of the incidence of malignant neoplasms of the abdominal cavity in the Bukovina region and possible determinants. Material and methods. The study was performed on the basis of RMNE "Chernivtsi Regional Clinical Oncology Center" and Clinic of Oncology of Bukovinian State Medical University and covers observation materials during 2015-2019 and statistical reporting on 102,247 cases of tumors of various localizations. The indicators were calculated using Access and Excel software packages based on the Microsoft Office environment. The results. The total number of malignant neoplasms of different localizations is relatively stable throughout the study period and ranged from 19903 to 21259 cases per year (average 20449.4±508.2 registered during the year). Neoplasms of the abdominal cavity are about the third of the total number of tumors of different localization with a certain tendency to grow. The distribution of patients with neoplasms of the abdominal cavity by stages of development is relatively uniform, despite significant variations in different localizations of tumors. Conclusions. A significant part of tumors of the abdominal cavity is diagnosed in the late (III-IV) stages of the pathological process, which leads to a decrease in the effectiveness of treatment. Significant differences in the clinical and epidemiological characteristics of neoplasms of various abdominal organs have been identified, which requires further study.

Aim. To determine the effects of vibration therapy devices exposure with a constant and aperiodic frequency of vibrations on the tissue of the biceps muscle of the shoulder. Material and methods. The study was conducted on 10 volunteers aged 24-35 years. the program Adobe Audition CC 2020, the device for vibration therapy with a constant vibration frequency “Charm 1-t”, the device for vibration therapy with an aperiodic vibration frequency “Individual massager with a pseudo-boiling layer” (MI EPS), the robotic biomechanical diagnostic and training complex with biological feedback CON-TREX were used. The measurement of the maximum strength of the biceps brachii muscle was carried out once to detect sensitivity to vibration, and then during 7 days for the dynamics of power characteristics. The maximum force was measured before exposure to vibrotherapy devices and immediately after exposure using the isokinetic classical mode of operation of the diagnostic system. Results. In a single measurement of biceps strength on one shoulder in a group of women, the average increase in muscle strength after using the Charm 1-T device was 0.8 N (2.3%), after using MI EPS – 1.9 N (6.4%). In the group of men, the average increase in muscle strength after using the device “Charm 1-T” was 1.9 N (3.2%), after using “MI EPS” – 4.6 N (7.2%). At the seven-day follow-up, the average increase in strength in the group of women on the right hand after using the Charm 1-T device was 21.8% (5.6 N), on the left hand after using MI EPS, the increase was 23.2% (6.1 N). In the group of men, the average increase in strength on the right hand after using “Charm 1-T” was 53% (30.7 N), on the left hand after using “MI EPS” – 15.5% (11.5 N). Conclusion. All participants in the study groups were determined to be sensitive to both types of vibration exposure. The study participants demonstrated an increase in strength indicators when testing the biceps muscle of the shoulder, and there was also an improvement in the tolerability of the procedure itself.

For railway locomotive, its motor bearing is one of the key components, which is likely to be damaged due to the intensified vibration conditions caused by the wheel-rail interaction and gear mesh....

В статье анализируется роль микроциркуляторных нарушений в патогенезе рубцовых изменений кожи, в том числе у пациентов с проявлениями метаболического синдрома. Исходные показатели микроциркуляторно-тканевых систем у пациентов с метаболическим синдромом свидетельствуют о более низких значениях уровня общей перфузии, чем у пациентов без признаков метаболических нарушений, что свидетельствует об угнетающем влиянии инсулинорезистентности на микроциркуляцию. Выявленная положительная динамика показателей микроциркуляторно-тканевой системы при проведении ультрафонофореза ферменкола в сочетании с методикой фракционной лазерной терапии позволяет рассматривать сосуды микроциркуляторного звена в качестве основной мишени при проведении коррекции рубцовых изменений кожи. Наблюдаемое через 4 недели после заключительной процедуры усиление нутритивного компонента кровотока и связанного с ним повышения скорости потребления кислорода и уровня окислительного метаболизма указывает на формирование пролонгированного эффекта. Преимущественное влияние рассмотренного способа коррекции рубцо-измененной кожи на отдельные компартменты микроциркуляторно-тканевой системы свидетельствует об эффективности технологии комплексного применения фракционного фототермолиза и ультрафонофореза коллагеназ, обладающей патогенетически ориентированным терапевтическим действием. Наличие в качестве фонового заболевания метаболического синдрома существенно ограничивает выраженность корригирующего эффекта, что обуславливает необходимость применения средств и методов из арсенала восстановительной медицины на основе преимущественного использования немедикаментозных лечебных факторов, которые, обладая выраженным саногенетическим потенциалом, позволяют максимально полно восстановить нарушенные функции при метаболическом синдроме и улучшить качество жизни человека The article analyzes the role of microcirculatory disorders in the pathogenesis of cicatricial changes in the skin, including in patients with manifestations of metabolic syndrome. The initial parameters of microcirculatory-tissue systems in patients with metabolic syndrome indicate lower values of the level of general perfusion than in patients without signs of metabolic disorders, which indicates the inhibitory effect of insulin resistance on microcirculation. The revealed positive dynamics of the indicators of the microcirculatory-tissue system during ultraphonophoresis of fermencol in combination with the method of fractional laser therapy allows us to consider the vessels of the microcirculatory link as the main target when correcting cicatricial changes in the skin. The increase in the nutritional component of the blood flow and the associated increase in the rate of oxygen consumption and the level of oxidative metabolism observed 4 weeks after the final procedure indicates the formation of a prolonged effect. The predominant influence of the considered method of correction of scar-altered skin on individual compartments of the microcirculatory-tissue system indicates the effectiveness of the technology of complex application of fractional photothermolysis and ultraphonophoresis of collagenases, which has a pathogenetically oriented therapeutic effect. The presence of metabolic syndrome as a background disease significantly limits the severity of the corrective effect, which necessitates the use of means and methods from the arsenal of restorative medicine based on the predominant use of non-drug therapeutic factors, which, having a pronounced sanogenetic potential, allow the most complete restoration of impaired functions in MS and improve the quality human life

Dimensional analysis has been very helpful in experimentation of very large or small-scale engineering systems. A good example would be experimentation on the aircrafts and ships, which was made co...

Little experimental data has been reported on the biomechanics of head collisions with drywall sections. The dynamics of head collisions with rigid structures are well documented. However, impacts with compliant, composite structures are more difficult to analyze. The study objective was to correlate the severity of a head impact with damage to the drywall. A human head analog was instrumented with a tri-axial accelerometer and a uniaxial load cell was placed along the cervical spine axis. A randomized block design of drop height and head orientation was utilized. The test results indicated a primarily linear correlation between drop height and peak head acceleration, as well as correlation between drop height and the geometry of the indentation to the drywall. Head posture had little influence on wall damage, however, head extension resulted in a stiffer head-spine complex compared to a flexed posture. A two-factor ANOVA determined a statistically significant correlation between damage severity and impact velocity. The results obtained can be used by accident reconstructionists to approximate the impact severity of a head impacting drywall. The study data are limited to drywall sections of known, similar geometry, and does not apply to scenarios with a support beam directly beneath the drywall. Further studies are needed to investigate additional head postures.

In this paper, a novel launch dynamics measurement system based on the photoelectric sensor pair is built. The actual muzzle time (i.e. a time duration that originates from the initial movement to the rocket’s departure from the muzzle) and the muzzle velocity are measured. Compared with the classical methods, the actual muzzle time is obtained by eliminating the ignition delay. The comparative analysis method is proposed with numerical simulations established by the transfer matrix method for multibody systems. The experiment results indicate that the proposed measurement system can effectively measure the actual muzzle time and reduce the error of classical methods, which match well with the simulation results showing the launch dynamics model is reliable and helpful for further analysis and design of the MLRS.

Using an improved travelling wave model, we have numerically investigated the dynamics of a Q-switched bismuth-doped fibre laser. Comparison of simulation results with previously reported experimental data demonstrates good agreement of the multipeak lasing structure and the shape of the strongest pulses at various levels of pumping. We have assessed the effect of the main laser parameters on output laser characteristics and quantitatively evaluated the effects of the nonsaturable loss in the active fibre and amplified spontaneous emission on output power saturation. Based on analysis of time-dependent light intensity and gain distributions in the gain medium at different instants in time, we have formulated recommendations how to improve output laser characteristics.

Background The etiology of mild traumatic brain injury (mTBI) remains elusive due to the tissue and cellular heterogeneity of the affected brain regions that underlie cognitive impairments and subsequent neurological disorders. This complexity is further exacerbated by disrupted circuits within and between cell populations across brain regions and the periphery, which occur at different timescales and in spatial domains. Methods We profiled three tissues (hippocampus, frontal cortex, and blood leukocytes) at the acute (24-hr) and subacute (7-day) phases of mTBI at single cell resolution. Results We demonstrated that the coordinated gene expression patterns across cell types were disrupted and re-organized by TBI at different timescales with distinct regional and cellular patterns. Gene expression-based network modeling implied astrocytes as a key regulator of the cell-cell coordination following mTBI in both hippocampus and frontal cortex across timepoints, and mt-Rnr2, which encodes the mitochondrial peptide humanin, as a potential target for intervention based on its broad regional and dynamic dysregulation following mTBI. Treatment of a murine mTBI model with humanin reversed cognitive impairment caused by mTBI through the restoration of metabolic pathways within astrocytes. Conclusions Our results offer a systems-level understanding of the dynamic and spatial regulation of gene programs by mTBI and pinpoint key target genes, pathways, and cell circuits that are amenable to therapeutics.

The effect of the optical feedback on the polarization flipping point and hysteresis loop was studied. The polarization flipping occurred at all angles between the polarizer axis and the laser polarization. The polarization flipping point changed by an optical feedback occurred at angles from 0° to 90°. Ability of choosing or controlling the laser polarization was determined by changing the direction of vertical and horizontal polarization by polarizer rotation in the external cavity from 0° to 90°.

BACKGROUND Visualization of aortic valve dynamics is important in diagnosing valvular diseases but is challenging to perform with magnetic resonance imaging (MRI) due to the limited temporal resolution. PURPOSE To develop an MRI technique with sub-millisecond temporal resolution and demonstrate its application in visualizing rapid aortic valve opening and closing in human subjects in comparison with echocardiography and conventional MRI techniques. STUDY TYPE Prospective. POPULATION Twelve healthy subjects. FIELD STRENGTH/SEQUENCE 3 T; gradient-echo-train-based sub-millisecond periodic event encoded imaging (get-SPEEDI) and balanced steady-state free precession (bSSFP). ASSESSMENT Images were acquired using get-SPEEDI with a temporal resolution of 0.6 msec. get-SPEEDI was triggered by an electrocardiogram so that each echo in the gradient echo train corresponded to an image at a specific time point, providing a time-resolved characterization of aortic valve dynamics. For comparison, bSSFP was also employed with 12 msec and 24 msec temporal resolutions, respectively. The durations of the aortic valve rapid opening (Tro ), rapid closing (Trc ), and the maximal aortic valve area (AVA) normalized to height were measured with all three temporal resolutions. M-mode echocardiograms with a temporal resolution of 0.8 msec were obtained for further comparison. STATISTICAL TEST Parameters were compared between the three sequences, together with the echocardiography results, with a Mann-Whitney U test. RESULTS Significantly shorter Tro (mean ± SD: 27.5 ± 6.7 msec) and Trc (43.8 ± 11.6 msec) and larger maximal AVA/height (2.01 ± 0.29 cm2 /m) were measured with get-SPEEDI compared to either bSSFP sequence (Tro of 56.3 ± 18.8 and 63.8 ± 20.2 msec; Trc of 68.2 ± 16.6 and 72.8 ± 18.2 msec; maximal AVA/height of 1.63 ± 0.28 and 1.65 ± 0.32 cm2 /m for 12 msec and 24 msec temporal resolutions, respectively, P

The friction draft gear with hysteresis characteristics is one of the typical nonlinear elements in longitudinal train dynamics (LTD). Due to the nonlinear hysteresis of friction damping, the disco...

The formation and propagation of streamers is an important precursor to determine the characteristics of electrical breakdown of many HV electrode configurations. Understanding of the study of the interaction between the polymer surface and the development process of the streamer is of major importance when we want to improve internal and external performance insulation systems. In this context, a numerical tool using neural networks is developed. This model allows evaluating the speed of streamers as a function of the amplitude of voltage initiation and the nature of the insulating materials. For this, a database was created to train the neural model from a laboratory model. This investigation builds a database for predicting the propagation of streamers on the polymers surface by different neuronal methods and this presents an interesting tool for estimating the propagation phenomena in functions of very important parameters

Рассматривается система уравнений динамики полета крылатой ракеты с учетом всех факторов воздействия на ее движение в атмосфере. A system of equations for the dynamics of a cruise missile flight is considered, taking into account all factors affecting its movement in the atmosphere.

Simultaneous and continuous joint angle estimation plays an important role in motion intention recognition and rehabilitation training. A surface electromyography (sEMG) state-space model is proposed to estimate simultaneous and continuous lower-limb-joint movements from sEMG signals in this article. The model combines the forward dynamics with Hill-based muscle model (HMM), making the extended model capable of estimating the lower-limb-joint motion directly. sEMG features including root-mean-square and wavelet coefficients are then extracted to construct a measurement equation used to reduce system error and external disturbances. With the proposed model, unscented Kalman filter is used to estimate joint angle from sEMG signals. In the experiments, sEMG signals were recorded from ten subjects during muscle contraction involving three lower-limb-joint motions (knee-joint motion, ankle-joint motion, and simultaneous knee-ankle-joint motion). Comprehensive experiments are conducted on three motions and the results show that the mean root–mean–square error for knee-joint motion, ankle-joint motion, and simultaneous motion of the proposed model are 5.1143°, 5.2647°, and 6.3941°, respectively, and significant improvements are demonstrated compared with the traditional methods.

Pipeline damage due to internal flow induced vibration is known to pose challenging problems in oil and gas industry. To reduce these problems, it is necessary to understand the vibration character...

In this perspective, we discuss recent observations related to the temporal dynamics of intensities in surface-enhanced Raman scattering (SERS) experiments. SERS is a well-established and highly ac...

The high-speed train needs excellent curve-passing performance, reducing wheel/rail force and wear, and sufficient hunting stability. According to the mechanism of self-steering radial bogie, the I...

This paper deals with the attitude motion of LEO satellites with deployable side panels designed for passive aerodynamic stabilization in a rarefied atmosphere. The influence of the aerodynamic and gravitational torques on the planar attitude motion near the unstable and stable equilibrium positions is studied. The presence of the unstable equilibrium position and small perturbations such as the oscillations of the flexible panels is the cause of chaos. A critical altitude is found above which the chaos is possible. The equations of planar attitude motion of the satellite with deployed flexible panels are obtained. The chaotic behavior of the system is demonstrated through numerical simulations of the attitude motion of a 3U CubeSat. The results of this paper can be used to analyze the applicability of passive aerodynamic stabilization for LEO satellites.

This paper reports on the influence of the asymmetric gain saturation on the dynamics of InGaAsP Fabry-Perot lasers. The results are obtained by numerical simulations of multimode rate equations. The gain saturation effects that results in competition phenomena among lasing modes are investigated. A hopping multimode case is examined in detail. With means of the bifurcation analysis the regions with instabilities in the evolution of the mode intensities have been found. The following operation in the plane of two parameters are obtained: stable single mode, stable multimode, bistabile, and multimode hopping. The pulse traces of amplitudes of modes are plotted to illustrate the observed behaviors. Finally, the influence of linewidth enhancement Henry factor on the laser behavior is investigated.

Purpose Magnetic resonance image (MRI) guided radiation therapy has the potential to improve outcomes for glioblastoma by adapting to tumor changes during radiation therapy. This study quantifies interfraction dynamics (tumor size, position, and geometry) based on sequential magnetic resonance imaging scans obtained during standard 6-week chemoradiation. Methods and Materials Sixty-one patients were prospectively imaged with gadolinium-enhanced T1 (T1c) and T2/FLAIR axial sequences at planning (Fx0), fraction 10 (Fx10), fraction 20 (Fx20), and 1 month after the final fraction of chemoradiation therapy (P1M). Gross tumor volumes (GTVs) and clinical target volumes (CTVs) were contoured at all time points. Target dynamics were quantified by absolute volume (V), volume relative to Fx0 (Vrel), and the migration distance (dmigrate; the linear displacement of the GTV or CTV relative to Fx0). Temporal changes were assessed using a linear mixed-effects model. Results Median volumes at Fx0, Fx10, Fx20, and P1M for the GTV were 18.4 cm3 (range, 1.1–110.5 cm3), 14.7 cm3 (range, 0.9–115.1 cm3), 13.7 cm3 (range, 0.6–174.2 cm3), and 13.0 cm3 (range, 0.9–76.3 cm3), respectively, with corresponding median Vrel of 0.88 at Fx10, 0.77 at Fx20, and 0.71 at P1M relative to Fx0 (P 5 mm during chemoradiation therapy. Conclusions Clinically meaningful tumor dynamics were observed during chemoradiation therapy for glioblastoma, supporting evaluation of daily MRI guided radiation therapy and treatment plan adaptation.

This study deals with drifting as one of the most important nonlinearities in vehicle dynamics. A four-wheel vehicle model is used to calculate the equilibria in planar motion, numerically, by intr...

Среди наиболее значимых заболеваний человека 4-е место, после сердечно-сосудистых, онкологических заболеваний и сахарного диабета, занимает остеопороз. Целью нашей работы было сравнение влияния 3- и 6-месячного введения аторвастатина (ATV) и α-кальцидола (α-К) на морфологические показатели костной ткани лабораторных крыс. Эксперимент проводился в течение 3-х и 6-ти месяцев на 240 лабораторных крысах, разделенных на 5 групп: интактные; «плацебо» (внутрижелудочное введение эквивалентного препаратам объёма 1% крахмала); животные, внутрижелудочно получавшие только ATV; животные, внутрижелудочно получавшие α-К и животные, внутрижелудочно получавшие ATV и α-К. Эвтаназия осуществлялась под эфирным наркозом. Кусочки бедренной кости размером 0,5 см выпиливали в области проксимального метафиза, а ветви нижнечелюстной кости – диастемы. Зону роста пропитывали серебром по Лилли и окрашивали по Ванн-Гизону. Исследование гистосрезов проводили на микроскопе Olympus BX-40. Размер вновь образованной костной ткани, окрашенной солями серебра в черный цвет, измеряли с помощью программы ImageScope-M. Количество сосудов считали в 10 полях зрения с расчетом среднего значения. Статистический анализ данных проведен с помощью пакета прикладных программ R 3.6.3 с учетом соответствия закону нормального распределения и применением поправок на множественные исследования. Отличия считали статистически значимыми при p-значении

Light-field microscopy has emerged as a technique of choice for high-speed volumetric imaging of fast biological processes. However, artifacts, nonuniform resolution and a slow reconstruction speed have limited its full capabilities for in toto extraction of dynamic spatiotemporal patterns in samples. Here, we combined a view-channel-depth (VCD) neural network with light-field microscopy to mitigate these limitations, yielding artifact-free three-dimensional image sequences with uniform spatial resolution and high-video-rate reconstruction throughput. We imaged neuronal activities across moving Caenorhabditis elegans and blood flow in a beating zebrafish heart at single-cell resolution with volumetric imaging rates up to 200 Hz. Reconstruction of light-field microscopy data with a deep-learning network achieves high reconstruction speed and reduces artifacts, as illustrated for moving C. elegans and beating zebrafish hearts.

The changes in the optical properties of water and hexane under femtosecond irradiation (Ti : Al2O3 laser, wavelength 800 nm, intensity ∼1013 W cm−2) are investigated in the cavitation (bubble-formation) regime using interference microscopy in a time interval of ∼1.5 ns since the impact onset. A comparison of the dynamics of radiation-induced processes (solvation of excess electrons, pair recombination, and development of precavitation processes) is performed. The excited-carrier concentration is estimated, and these estimates are found to be inconsistent with the amount of energy that must be transferred to the liquid during a pulse to implement its heating and subsequent cavitation. This inconsistency is especially pronounced for hexane, where ionisation processes can barely be detected by interferometry. The experimental results put new questions about the mechanisms of energy transfer in both polar and nonpolar liquids subjected to intense laser irradiation.

It has been found in existing research works that the dc-link dynamics are significant internal dynamics in the type-IV wind turbine system, which can shape system characteristics and influence system stability. If dc-link dynamics are weakly damped, this dynamic behavior may reduce system damping and worsen system stability. Considering that dc-link dynamics are determined by the interaction effects of controllers and different control structures can be adopted to regulate dc-link voltage in the type-IV wind turbine system, analytical models are needed to accurately evaluate and analyze dc-link dynamics under different control structures, which are lacked in existing publications. In this article, the mechanism of dc-link dynamics in the system is described at first. A single-in-single-out indicator function is proposed to model the dc-link dynamics, based on which a linearized state-space model of dc-link dynamics is obtained. Then, the eigenvalue sensitivity matrix is applied to determine the influencing factors of dc-link dynamics and possible causes of weakly damped dc-link dynamics. DC-link dynamics under different control structures are compared. The influenced system characteristics can also be modeled by the proposed model of dc-link dynamics and the system stability with weakly damped dc-link dynamics is also investigated with experiments based on control-hardware-in-loop platform.

The OpenFOAM computational fluid dynamics code was used to investigate the performance of three combustion models, namely, Muppala, Zimont and Algebraic. The performance characteristics of these mo...

To investigate the properties of a large-scale brain network, it is a common practice to reduce the dimension of resting state functional magnetic resonance imaging (rs-fMRI) data to tens to hundreds of nodes. This study presents an analytic streamline that incorporates modular analysis and similarity measurements (MOSI) to fulfill functional parcellation (FP) of the cortex. MOSI is carried out by iteratively dividing a module into sub-modules (via the Louvain community detection method) and unifying similar neighboring sub-modules into a new module (adjacent sub-modules with a similarity index

A numerical analysis of the effect of temperature on the dynamics of the sandwich beam model with a viscoelastic core is presented. The beam under analysis was described with a standard rheological model. This solution allows one to study the effect of temperature on material strength properties. Calculations were performed with the Finite Element Method in the ANSYS software. The analysis of the results of the numerical calculations showed a significant influence of temperature on the strength properties of the model under test. The analysis confirmed damping properties of viscoelastic materials.

An analytical study is performed on the stability of soliton-like pulses propagating in a fiber in the mode of tunneling ionization and stimulated Raman self-scattering. It is shown that the mutual compensation of these effects is possible under certain conditions for the parameters of the medium and the signal.

Wind as an environmental condition plays a crucial role in the heat dynamics of pavement solar collectors (PSCs) and causes convective heat loss to the ambient. The major emphasis of the present study is to evaluate the effects of wind velocity on the thermal efficiency of glazed and unglazed PSCs. Since the wind velocity is a chaotic and random function, it is challenging to evaluate wind velocity effects experimentally. Therefore, a PSC prototype was constructed, and a computational fluid dynamic (CFD) model was developed and validated by the acquired experimental results. Then, the CFD model was employed to evaluate the wind velocity effects on the dynamics of PSCs. Three scenarios considering wind velocities in the ranges from 0 m/s to 20 m/s were assumed, and the dynamics of the constructed glazed and unglazed PSCs were monitored. The obtained results illustrated that by increasing wind velocity from 0 m/s to 20 m/s, the maximum outlet water temperature decreases by near 25% and 10% for the unglazed PSC and glazed one, respectively. The validated numerical model shows that increasing wind velocity caused the thermal performance to be reduced by around 68% and 25% for the unglazed and glazed PSCs, respectively.