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Due to the sensitivity of the sonochemical production to the different operating conditions, in the present paper, a microscopic investigation is conducted to evaluate the impact of methanol concentration on the bubble temperature and hydroxyl radicals yielding. This analysis has been conducted by spanning a range of ultrasound frequency (from 140 to 515 kHz), acoustic intensity (1 and 2 W/cm2), and liquid temperature (from 10 to 50°C). Whatever the used frequency (140–515 kHz), the variation of bubble temperature and OH formation has been negatively impacted in the presence of methyl alcohol, with a plateau from 0.1 mM methanol. On the other side, the evolution of the peak temperature and OH production were found to be frequency dependent. Moreover, in the absence of methanol, the formation of hydroxyl radicals is in the same order as that of bubble temperature (50 > 40 > 30 > 20 > 10°C), whereas, in the presence of methanol, an optimal production of OH is obtained at 20°C for all methanol concentrations. The decrease in bubble temperature was accelerated with the rise of liquid temperature, where no sono-activity is obtained at the liquid temperature of 50°C. Based on the effects of wave frequency, acoustic intensity, and the liquid temperature, it has been concluded that the inhibition process of methanol alcohol toward the OH radicals is predominantly taking place at the bubble interface (bubble/solution region) rather than the cavitation interior (gas phase). [ABSTRACT FROM AUTHOR]

In 1904, the Austrian physicist Fritz Hasenöhrl examined by means of mental experiments the black body radiation in a reflecting cavity. By calculating the work required to keep the cavity moving at constant velocity in opposition to the radiation pressure, he calculated for the radiation energy a value equivalent to E=38mc2, relation corrected in 1905 to E=34mc2. This relation establishes an equivalence between mass and radiation energy E and was finally corrected to the present known form E=mc2 by Einstein. The conclusion from these deductions is that light has mass and inertia. Based on a thought experiment inspired by Hasenöhrl’s, in which we accelerate a reflecting cavity containing an internal radiation flux, we conclude that, under certain conditions of motion, light verifies Newton’s 2nd Law of Inertia.

Pc1 pulsations are infrequently observed at mid-latitude ground stations. Previous studies have shown that these pulsations near the ground are commonly observed during dawn and geomagnetic storms, particularly in the storm recovery phase. However, few studies have directly compared the characteristics of Pc1 pulsations during storm and non-storm times using long-term ground-based data. In this study, we conducted a comparative analysis of storm-related and non-storm-related Pc1 pulsations detected at a mid-latitude ground station located at Bohyun mountain in Korea (BOH, L~1.34). Our findings reveal notable distinctions between the two groups. Pc1 pulsations during the non-storm period exhibit a sharper peak in the local time distribution of the occurrence, relatively well indicating daytime wave power attenuation during propagation. Additionally, during the non-storm period, Pc1 pulsations show relatively lower frequencies (0.6~1 Hz) with predominantly linear polarization. In contrast, storm-related Pc1 pulsations exhibit higher and broader frequencies (up to 3 Hz) with more frequent left-handed polarization. These results suggest that storm-related Pc1 pulsations might originate from a more diverse range of spatial sources.

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The φ 6 -model expansion technique is used in this work to obtain dark, bright, periodic, singular, dark-bright, combined singular soliton and rational solutions to the Hamiltonian amplitude equation. This equation is used to analyze the stability of the exact solutions as well as to determine modulated wave train instabilities. The obtained results are mostly applicable in the study of nonlinear waves in plasma in the setting of a non-magnetized fluid-type plasma, the dispersion of the Langmuir (electrostatic) wave when it generates some low-frequency acoustic waves, such as the ion-acoustic wave, and other fields. The behavior of the traveling wave is analyzed using the frequency values, which is one of the internal dynamics of the dark soliton. This discussion is supported by graphs and the effects on wave behavior of different densities are simulated. [ABSTRACT FROM AUTHOR]

Abstract The important parameters to describe waves are their amplitude and length. In order to make it easier to improve wave amplitude and facilitate wave experiment, a simple push-type wave generating method using digital rotary valve control was proposed and different wave amplitudes were generated by the new method. After the mathematical model of the new method had been established, numerical analysis based on the linear wave theory was carried out by means of Matlab/Simulink software tools, and experiments were conducted on the push-type wave maker to ascertain the validity of the established model and the numerical simulation results. It shows that both experimental and theoretical results agree relatively well, and the plate motion frequency and amplitude of the push-type wave maker can be continuously adjusted and the various required regular waves can be obtained. Although the wave amplitude and length descends with the increasing of working frequency, the wave amplitude can be improved conveniently by setting the axial opening width of the valve and the oil supply pressure of system. The wave length remains unchanged with the axial opening width and the oil supply pressure change. The research indicates that different regular waves can be easily generated by the new method and the wave amplitude can be further improved in a certain plate motion frequency range.

Nonlinear regular wave effects on a dropped cylinder are studied and compared with those of linear waves. A 3D second-order wave model is employed to simulate the falling process of a dropped cylinder under nonlinear regular waves. The calculated results for nonlinear regular wave simulations, nonlinear regular wave effects on the trajectory, landing point and falling time of the dropped cylinder into different water depths, waves at zero and nonzero wave heading angles with different frequencies and amplitudes are compared with the corresponding results under linear regular wave simulations. It is found that wave heading, wave frequency, water depth, wave amplitude, and the selection of regular wave model (linear or nonlinear) are factors that may significantly influence the motion of the dropped cylinder. [ABSTRACT FROM AUTHOR]

The important parameters to describe waves are their amplitude and length. In order to make it easier to improve wave amplitude and facilitate wave experiment, a simple push-type wave generating method using digital rotary valve control was proposed and different wave amplitudes were generated by the new method. After the mathematical model of the new method had been established, numerical analysis based on the linear wave theory was carried out by means of Matlab/Simulink software tools, and experiments were conducted on the push-type wave maker to ascertain the validity of the established model and the numerical simulation results. It shows that both experimental and theoretical results agree relatively well, and the plate motion frequency and amplitude of the push-type wave maker can be continuously adjusted and the various required regular waves can be obtained. Although the wave amplitude and length descends with the increasing of working frequency, the wave amplitude can be improved conveniently by setting the axial opening width of the valve and the oil supply pressure of system. The wave length remains unchanged with the axial opening width and the oil supply pressure change. The research indicates that different regular waves can be easily generated by the new method and the wave amplitude can be further improved in a certain plate motion frequency range. [ABSTRACT FROM AUTHOR]

Modes of vibration play a dominant role in the design of WTG (Wind Turbine Generator) support structures. It is necessary to choose the overall system frequency such that the modes of vibration do not coincide with the rotor frequencies as well as the wave frequencies. WTG supported on multiple foundations (such as jackets or seabed frames) may exhibit rocking modes of vibration if the vertical stiffness of the foundation is not large enough which in turn may have serious implications on the fatigue performance of the overall structure. From the O&M (Operation and Maintenance) point of view, it is necessary to design the overall system to have sway-bending as the dominant mode of vibration. This paper develops a formulation for obtaining foundation (for both piles and shallow suction caissons) sizes and spacing such that rocking vibrations are prevented and sway-bending vibrations are achieved. Expressions for the minimum vertical stiffness of foundations are proposed for different configurations: square base, symmetrical (equilateral) triangle, or asymmetrical (isosceles) triangle. Verification of the method is carried out through finite element analysis and a step-by-step solved example is taken to show the application of the formulation. It is hoped that the formulation will assist designers to optimize the foundation arrangement and provide preliminary sizing for tender design. • Establishing criteria for different modes of vibrations for jackets supporting wind turbines. • Formulations for the minimum vertical stiffness of foundation to avoid rocking. • Example showing the applicability of the formulation. • Effects of foundation configuration (symmetric or symmetric) and spacing on modes of vibration. [ABSTRACT FROM AUTHOR]

Abstract In the floating wave power system, when the natural frequency of the float coincides with the wave frequency, the system would theoretically work in the resonance state, which consequently makes the capture efficiency of wave energy conversion device reach the maximum. The natural frequency of the float is related to many parameters, including the float size and shape, float stiffness, float mass, float additional mass, etc. The variation of float mass might cause other parameters, like draught, additional mass and hydrodynamic coefficients, to change. This is one of the important reason why there is still no efficient and accurate method for mass adjustment. In order to solve this problem, a mass-adjustable float is designed, and a new optimization calculation method for the float based on the high-order polynomial fitting theory is proposed. The optimized method combines the advantages of boundary element analysis and numerical calculation. It introduces an additional coefficient K related to the wave frequency and the draught of the float to optimize the Hooft's approximate equation between the additional mass and the float size. This optimized method can greatly improve the computational efficiency without reducing calculation accuracy. Finally, the heaving response of the mass-adjustable floats at different wave frequencies are calculated in AQWA, which verifies that the mass-adjustable floats have higher wave capture efficiency than ordinary floats. [ABSTRACT FROM AUTHOR]

Some of the prominent features in later stages of the Benjamin-Feir (BF) instability development are still not well clarified: What are the conditions for a permanent downshifting in the wave energy spectrum, is this process inevitable accompanied by wave breaking dissipation? What is the mechanism of multiple downshifting and discrete energy spreading to higher frequencies, how does it depend on the initial steepness and frequency space of waves? We conducted experimental and theoretical studies on this issue and revealed a number of new features of the development of instability in the late stages of wave's evolution. We employ the reduced (truncated) version of Zakharov equations, the multi-wave near-neighbor resonance model (NN model), which takes into account the most effective quasi-resonances with minimum detuning from the exact resonance conditions. We show that the near-neighbor model of wave interactions can adequately describe the number of new characteristic features of BF instability. NN model is much simpler than Zakharov equation for computation and analysis. The dissipation version of Zakharov equations based on the Tulin's semi-empirical model is employed for the description of breaking wave's propagation. We verify the new characteristic features of BFI for various initial wave conditions by experiments conducted in Tainan Hydraulics Laboratory and confirm the theoretical predictions of NN model. A strong permanent downshifting of the spectral maximum for gentle waves without wave breaking is revealed for initially two-time narrower spectral width in comparison with the most unstable case. For steep waves, a multiple downshifting regime is detected, accompanied by a wave breaking. The discrete energy flow to higher spectral components takes place in the breaking and no-breaking regimes. Results of numerical simulations of Zakharov and NN models reasonably correspond to each other and to our experimental and field observations on wave modulation. [ABSTRACT FROM AUTHOR]

Aims: Catecholaminergic polymorphic ventricular tachycardia type 1 (CPVT1) predisposes to ventricular tachyarrhythmias (VTs) during high heart rates due to physical or psychological stress. The essential role of catecholaminergic effects on ventricular cardiomyocytes in this situation is well documented, but the importance of heart rate per se for arrhythmia initiation in CPVT1 is largely unexplored. Methods and results: Sixteen CPVT1 patients performed a bicycle stress-test. Occurrence of VT triggers, i.e. premature ventricular complexes (PVC), depended on high heart rate, with individual thresholds. Atrial pacing above the individual PVC threshold in three patients did not induce PVCs. The underlying mechanism for the clinical observation was explored using cardiomyocytes from mice with the RyR2-R2474S (RyR2-RS) mutation, which exhibit exercise-induced VTs. While rapid pacing increased the number of Ca2+ waves in both RyR2-RS and wild-type (p<0.05), β-adrenoceptor (βAR) stimulation induced more Ca2+ waves in RyR2-RS (p<0.05). Notably, Ca2+ waves occurred despite decreased sarcoplasmic reticulum (SR) Ca2+ content in RyR2-RS (p<0.05), suggesting increased cytosolic RyR2 Ca2+ sensitivity. A computational model of mouse ventricular cardiomyocyte electrophysiology reproduced the cellular CPVT1 phenotype when RyR2 Ca2+ sensitivity was increased. Importantly, diastolic fluctuations in phosphorylation of RyR2 and SR Ca2+ content determined Ca2+ wave initiation. These factors were modulated towards increased propensity for arrhythmia initiation by increased pacing rates, but even more by βAR stimulation. Conclusion: In CPVT1, VT propensity depends on individual heart rate thresholds for PVCs. Through converging data from clinical exercise stress-testing, cellular studies and computational modelling, we confirm the heart rate-independent pro-arrhythmic effects of βAR stimulation in CPVT1, but also identify an independent and synergistic contribution from effects of high heart rate. [ABSTRACT FROM AUTHOR]

In viscous fluid-saturated elastic porous media, the spherical dilatational wave displacement equations are developed on Biot's theory and the spherical shear wave displacement equations are developed based on a modified wave frame. Analytical forms of the solutions are introduced by considering the wave magnitude dispersion due to the viscosity of Newtonian fluids. The attenuation of dilatational wave and shear wave are separately studied. Due to the high attenuation of the shear wave, the superposition characteristic is only considered for dilatational waves under the multiple energy source models. Many advantages of the multiple sources over the single source have been theoretically or numerically demonstrated, such as multiple energy sources can produce a larger relative displacement than single source, the wave direction is controllable and the magnitude of the relative displacement can be adjusted as required under the multiple source. [ABSTRACT FROM AUTHOR]

Deep-sea mining (DSM) is an advanced concept. A simulation method of coupled vessel/riser/body system in DSM combined with dynamic positioning (DP) is proposed. Based on the three-dimensional potential flow theory, lumped mass method, and Morison’s equations the dynamic models of the production support vessel, riser and slurry pump are established. A proportion integration differentiation (PID) controller with a nonlinear observer and a thrust allocation unit are used to simulate the DP system. Coupled time domain simulation is implemented with the vessel operated in two DP modes. Results of the vessel and pump motions, riser tension, and thruster forces are obtained. It shows that the pump will be lifted by the riser when the vessel is chasing the next set point. Riser tension is influenced by the wave frequency motions of the vessel in positioning mode and low-frequency motions in tracking mode. The proposed simulation scheme is practical to study the DSM operation. [ABSTRACT FROM AUTHOR]

The paper presents an experimental study in a laboratory flume to investigate the combined wave-current flow over a pair of hemispherical obstacles placed at a relative spacing L/d = 4, where L is a center to center distance between the obstacles and d is the obstacle height. Detailed velocity data were collected using three-dimensional micro-acoustic Doppler velocimeter from upstream to downstream of the pair of obstacles along the centerline of the flume. This study examines the mean flows, eddy viscosity, mixing length, turbulence kinetic energy (TKE) flux under the influence of two hemispherical obstacles in combined wave-current flow conditions. The analysis reveals that higher level of turbulence including maximum eddy viscosity and TKE flux is observed near the top of the obstacles. Further, the power spectral density (PSD) for velocity fluctuation is also analyzed to study the internal structure of turbulence due to combined wave-current flow over hemispherical obstacles. [ABSTRACT FROM AUTHOR]

In upward air-water churn flow in a vertical tube, the liquid fed at the inlet is entrained upwards by the gas flow in the core, resulting in a wavy film flow. The present work considers the influence of the modelling of the liquid inlet on the wave frequencies, with the final purpose to understand the causes and effects in an actual flow. The perforated wall liquid inlet section, commonly used in experiments, is modelled in simulations as a simple inlet boundary condition on a short section of a pipe wall. At a given liquid mass flow rate in the experiment, the magnitude of the wall normal velocity component is controlled by the inlet area, which is used as a modelling parameter in the present study. The study shows that the calculated wave frequency is proportional to the imposed wall normal velocity at the liquid inlet. The velocity profile at the perforated wall liquid inlet section was not measured in available experiments and presents a major source of uncertainty in simulations. The parametric study revealed that a suitable value for the magnitude of the wall normal velocity can be determined over a range of flow conditions, leading to good agreement of simulated and measured wave frequencies. This finding suggests, that the wave frequency in actual churn flow is not a property depending only on geometric and flow conditions, but on the liquid inlet flow as well. Simulations were performed in three-dimensional tube section using the multiphase solver interFoam from the open-source code OpenFOAM. [ABSTRACT FROM AUTHOR]

Interfacial wave parameters, in this case the frequency, height, velocity, and slope, were investigated experimentally in a horizontal air-water stratified flow. Experiments were conducted with a parallel wire conductance sensor and PIV visualization in a rectangular channel, of which the width and height are 40 mm and 50 mm, respectively. In the experiments, the flow condition covered the liquid Reynolds number Re l range of 450 to 3540 and the gas Reynolds number Re g range of 14,000 to 70,000. The results revealed that the observed wave types according to the flow conditions in the rectangular channel are similar to those in a horizontal pipe. The frequency, height, and slope of the interfacial wave show complicated tendencies according to the combination of Re g and Re l , which affects the coalescence and breakup of the wave. Specifically, the wave height and wave slope have opposite tendencies regarding the criterion of Re g = 34,000. For cases in which Re g  ≥  34,000, the interfacial drag force significantly affects the height and slope of the disturbance wave. In contrast, for Re g < 34,000, the growth of the wave has an important effect on the wave parameters. Finally, new empirical correlations for the frequency, height, and slope of the interfacial wave were proposed for application to the development of a droplet entrainment model in a horizontal stratified flow. [ABSTRACT FROM AUTHOR]

A two-fluid modelling approach with interface sharpening is applied for numerical simulations of flooding waves in air-water co-current flow in vertical pipe. The simulation capability of Neptune_CFD code is analysed. The results are compared with experimental data and with the simulations performed with the computational code ANSYS CFX. Isothermal flow of air and water in the churn flow regime is modelled. Turbulence is modelled for each phase separately using URANS approach. A typical geometry of a test section in the vicinity of the liquid injector is used as the computational domain. In general, both computational codes predicted similar wave frequency values for the pipe with internal diameter of 32 mm and show good agreement with the experimental data. Detailed analysis of local flow phenomena in the case of 2D Neptune_CFD simulation however reveals a significant accumulation of liquid in the centre of the pipe that may be attributed to the axisymmetric assumption, drag force formulation, and possible numerical errors. It was demonstrated that the liquid accumulation in the centre of the pipe can be avoided by the simulations in the full 3D domain due to asymmetric nature of the churn flow. [ABSTRACT FROM AUTHOR]

Structures of thin films bonded on thick substrates are abundant in biological systems and engineering applications. Mismatch strains due to expansion of the films or shrinkage of the substrates can induce various modes of surface instabilities such as wrinkling, creasing, period doubling, folding, ridging, and delamination. In many cases, the film-substrate structures are not flat but curved. While it is known that the surface instabilities can be controlled by film-substrate mechanical properties, adhesion and mismatch strain, effects of the structures' curvature on multiple modes of instabilities have not been well understood. In this paper, we provide a systematic study on the formation of multimodal surface instabilities on film-substrate tubular structures with different curvatures through combined theoretical analysis and numerical simulation. We first introduce a method to quantitatively categorize various instability patterns by analyzing their wave frequencies using fast Fourier transform (FFT). We show that the curved film-substrate structures delay the critical mismatch strain for wrinkling when the system modulus ratio between the film and substrate is relatively large, compared with flat ones with otherwise the same properties. In addition, concave structures promote creasing and folding, and suppress ridging. On the contrary, convex structures promote ridging and suppress creasing and folding. A set of phase diagrams are calculated to guide future design and analysis of multimodal surface instabilities in curved structures. [ABSTRACT FROM AUTHOR]

In this work, we explicitly show the existence of two frequency regimes in a two-dimensional Hindmarsh–Rose neural network. Each of the regimes, through the semi-discrete approximation, is shown to be described by a two-dimensional complex Ginzburg–Landau equation. The modulational instability phenomenon for the two regimes is studied, with consideration given to the coupling intensities among neighboring neurons. Analytical solutions are also investigated, along with their propagation in the two frequency regimes. These waves, depending on the coupling strength, are identified as breathers, impulses and trains of soliton-like structures. Although the waves in two regimes appear in some common regions of parameters, some phase differences are noticed and the global dynamics of the system is highly influenced by the values of the coupling terms. For some values of such parameters, the high-frequency regime displays modulated trains of waves, while the low-frequency dynamics keeps the original asymmetric character of action potentials. We argue that in a wide range of pathological situations, strong interactions among neurons can be responsible for some pathological states, including schizophrenia and epilepsy. [ABSTRACT FROM AUTHOR]

An experimental study is performed to study the effect of inner and outer injection pressure on spray characteristics and the detailed structure of interacted liquid sheets of a coaxial swirl injector. A high speed camera is used to visualize the transition merging process of the coaxial swirling liquid sheet. A laser reflection system is set up to analyze the wave frequency of liquid sheet. A Malvern RTSizer is used to measure the droplet size of the coaxial spray. It is found that the structure of the interacted spray is considerably different from the individual spray, the interaction between the inner and outer liquid film promoted the breakup. At the same injection pressure, the temporal instability of a liquid sheet does not change spatially. For both individual and coaxial spray, the wave frequency increase as the injection pressure increase. The individual inner spray is more unstable and easier to breakup. Furthermore, the relationship between the surface instability and the droplet size distribution of the coaxial liquid spray is investigated quantitatively. For both individual spray and coaxial sprays, the Sauter Mean Diameter (SMD) decrease as the inner injection pressure increase. The inner spray has a higher weighing factor that influences the SMD of the coaxial spray. For coaxial spray at low inner injection pressure, the liquid film thickness would be the dominate factor to the SMD. [ABSTRACT FROM AUTHOR]

In this study, the effects of frequency, height and wavelength of progressive gravity waves on vibration and energy absorption of the single- and two-degree of freedom Bristol oscillating cylinder systems have been investigated experimentally and numerically in different depth of water. The experiments were carried out in channel equipped with both a paddle-type wave-maker and wave features measurement tools. Numerical simulations were conducted in COMSOL software assigned to simulate interactions between physical environments for turbulent flow. Making a comparison between the numerical and experimental conclusions compared to the other researchers' results demonstrates a desired matching in a wide range of waves' parameters. It can be seen in findings that changing in depth of submerged objects from free surface of water has considerable influence on their vibration behavior, so that by rising in depth, the oscillations amplitude increases to a maximam and then decreases. The obtained results indicate the different effects of relative depth under the submerged buoy on the efficiency of the single- and two-degree of freedom systems; so that increasing water height causes rise in the efficiency of single degree of freedom systems, but it doesn't have considerable influence on two degree of freedom systems. The results also show that expanding the wave-maker frequency for a constant height of water in channel causes to rise in energy and height of the generated waves so that oscillations amplitude of submerged buoy rise in vertical and horizontal line. [ABSTRACT FROM AUTHOR]

The present study investigates the frequency-temperature coupling effects on wave propagation through granite. The pendulum impact test was conducted on the thermally treated long granite bars. The wave propagation coefficients, such as attenuation ratio and wave velocity, were determined for the granite under five groups of high-temperature and six groups of incident waves with different frequencies. A relationship between the dynamic modulus of granite, frequency of stress wave and the high temperature was revealed. The frequency-temperature coupling effects on the dynamic modulus were discussed. The results show that the attenuation ratio, wave velocity and dynamic elastic modulus increase with the increase of frequency. The attenuation ratio increases with the increase of temperature, while the wave velocity and dynamic elastic modulus decrease with the increase of temperature. The proposed relationship between the dynamic modulus, frequency and temperature can efficiently describe the frequency-temperature coupling effects on the granite with acceptable error. The present study has potential in the application of wave propagation through granite in the high-temperature environment. • Frequency-temperature coupling effects on wave propagation were investigated. • Relationship between dynamic modulus, frequency and high temperature was revealed. • Frequency-temperature coupling effects on the dynamic modulus were discussed. [ABSTRACT FROM AUTHOR]

It is shown that a pontoon is capable of producing parametric pitching, both in the longitudinal and in the transverse directions, due to periodic changes in metacentric heights of the pontoon on the astir surface of the liquid in the sump of an open coal mine. The equation describing parametric pitching is transformed to the Mathieu equation, whose factors depend both on the own frequencies and the pontoon floatability features on 'calm water,' and on the frequency of fluctuations of the liquid, which, in turn, is defined by the sump size. Regular relationships between parameters characterizing parametric pitching in the longitudinal and transverse directions and areas of its instability are obtained. [ABSTRACT FROM AUTHOR]

Objectives: To perform a systematic review and network meta-analysis of randomized controlled trials (RCTs) to determine the optimal shock wave lithotripsy (SWL) frequency range for treating urinary stones, i.e., high-frequency (100–120 waves/minute), intermediate-frequency (80–90 waves/minute), and low-frequency (60–70 waves/minute) lithotripsy. Materials and Methods: Relevant RCTs were identified from electronic databases for meta-analysis of SWL success and complication rates. Using pairwise and network meta-analyses, comparisons were made by qualitative and quantitative syntheses. Outcome variables are provided as odds ratios (ORs) with 95% confidence intervals (CIs). Results: Thirteen articles were included in the qualitative and quantitative synthesis using pairwise and network meta-analyses. On pairwise meta-analyses, comparable inter-study heterogeneity was observed for the success rate. On network meta-analyses, the success rates of low- (OR 2.2; 95% CI 1.5–2.6) and intermediate-frequency SWL (OR 2.5; 95% CI 1.3–4.6) were higher than high-frequency SWL. Forest plots from the network meta-analysis showed no significant differences in the success rate between low-frequency SWL versus intermediate-frequency SWL (OR 0.87; 95% CI 0.51–1.7). There were no differences in complication rate across different SWL frequency ranges. By rank-probability testing, intermediate-frequency SWL was ranked highest for success rate, followed by low-frequency and high-frequency SWL. Low-frequency SWL was also ranked highest for low complication rate, with high- and intermediate-frequency SWL ranked lower. Conclusions: Intermediate- and low-frequency SWL have better treatment outcomes than high-frequency SWL when considering both efficacy and complication. [ABSTRACT FROM AUTHOR]

Assessing the fatigue life of mooring systems is important for deep water structures. In this paper, a comprehensive fatigue analysis is conducted on the mooring lines applied in a semi-submersible platform with special focus on the low frequency (LF) fatigue damage. Several influential factors, including water depth, wave spectral parameters, and riser system, are considered. Numerical simulation of a semi-submersible platform with the mooring/riser system is executed under different conditions, and the fatigue damage of mooring lines is assessed by using the time domain analysis method as a benchmark. The effects of these factors on the mooring line tension and the fatigue damage are investigated and discussed in detail. Research results indicate that the LF fatigue damage only accounts for a very small portion of the total damage, although the LF components dominate the global motion response and the mooring line tension of the semi-submersible platform. However, it is demonstrated that the LF fatigue damage is clearly affected by the influential factors. The increase in water depth and spectral peak periods, and the existence of risers can weaken the contribution of the LF components to the mooring line fatigue damage, while the fatigue damage due to the LF components increases with the increase of significant wave height. [ABSTRACT FROM AUTHOR]

Abnormal cellular Ca2+ handling contributes to both contractile dysfunction and arrhythmias in heart failure. Reduced Ca2+ transient amplitude due to decreased sarcoplasmic reticulum Ca2+ content is a common finding in heart failure models. However, heart failure models also show increased propensity for diastolic Ca2+ release events which occur when sarcoplasmic reticulum Ca2+ content exceeds a certain threshold level. Such Ca2+ release events can initiate arrhythmias. In this study we aimed to investigate if both of these aspects of altered Ca2+ homeostasis could be found in left ventricular cardiomyocytes from rats with different states of cardiac function six weeks after myocardial infarction when compared to sham-operated controls. Video edge-detection, whole-cell Ca2+ imaging and confocal line-scan imaging were used to investigate cardiomyocyte contractile properties, Ca2+ transients and Ca2+ waves. In baseline conditions, i.e. without beta-adrenoceptor stimulation, cardiomyocytes from rats with large myocardial infarction, but without heart failure, did not differ from sham-operated animals in any of these aspects of cellular function. However, when exposed to beta-adrenoceptor stimulation, cardiomyocytes from both non-failing and failing rat hearts showed decreased sarcoplasmic reticulum Ca2+ content, decreased Ca2+ transient amplitude, and increased frequency of Ca2+ waves. These results are in line with a decreased threshold for diastolic Ca2+ release established by other studies. In the present study, factors that might contribute to a lower threshold for diastolic Ca2+ release were increased THR286 phosphorylation of Ca2+/calmodulin-dependent protein kinase II and increased protein phosphatase 1 abundance. In conclusion, this study demonstrates both decreased sarcoplasmic reticulum Ca2+ content and increased propensity for diastolic Ca2+ release events in ventricular cardiomyocytes from rats with heart failure after myocardial infarction, and that these phenomena are also found in rats with large myocardial infarctions without heart failure development. Importantly, beta-adrenoceptor stimulation is necessary to reveal these perturbations in Ca2+ handling after a myocardial infarction. [ABSTRACT FROM AUTHOR]

The effects of fluid properties on the wave velocity and frequency of gas–liquid annular two-phase flow were investigated in 26 and 16-mm inner pipe diameters. The liquid viscosity was varied from 1.02 to 6.57 mPa s using water and glycerol solution and the surface tension was varied from 34.0 to 71.7 mN/m using water and butanol solution. The range of superficial liquid and gas velocities were set to 0.05–0.2 m/s and 12–40 m/s, respectively. In general, the wave frequency decreases with increasing liquid viscosity and decreasing surface tension. The wave velocity decreases with increasing liquid viscosity for all range of superficial gas and liquid velocities. The lower surface tension gives the lower wave velocity for low superficial liquid velocity. For high superficial liquid velocity, however, the wave velocity increases with decreasing surface tension. The wave frequency decreases with the increase of liquid viscosity and the decrease of surface tension, with more significant effects are found at the higher superficial gas and liquid velocities. Comparisons of experimental data with the existing correlations for wave velocity and wave frequency have been carried out and new correlations have been developed with a considerably good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

Wave energy is directly converted into the propulsion of wave gliders by using the flapping hydrofoils. The propulsive performance of the wave glider has relationships with some parameters, especially spring constant of the submerged flapping hydrofoil mechanism and wave frequency. A numerical model of the submerged passive flapping hydrofoil based on the float response of the single-body architecture wave glider was established to analyze its propulsion in this paper. The float response was analyzed by using Advanced Quantitative Wave Analysis (AQWA) software under different wave frequencies in time domain and frequency domain. The numerical model of the hydrofoil was established, and the forward speed under different wave frequencies and spring constants were analyzed by using ANSYS-FLUENT software. By means of the polynomial curve fit, the corresponding equation describing the response of average forward speed was established. Tank experiment and sea trial were carried out to verify the accuracy of the model and the propulsive performance of the single-body architecture wave glider. The results showed that the speed fluctuation of the flapping hydrofoil was smaller as wave frequency increased under four wave frequencies. At the same time, wave frequency had a close relationship with spring constant, and there was an optimal spring constant under different wave frequencies to maximize the navigation speed of the whole system. • A numerical model of the hydrofoil based on the surface float response is built. • The response of the pitch motion of the surface float will increase with the increase of wave frequencies. • There is an optimal spring constant to obtain the optimal attack of angle of the hydrofoil under different wave frequencies. • The speed fluctuation of the flapping hydrofoil is smaller as wave frequency increases. [ABSTRACT FROM AUTHOR]