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This study investigates interaction between an impact liquid drop and a sessile drop on both flat and cylindrical substrates, focusing mainly on the combined liquid spreading and oscillation under low impact velocity with aid of high-speed photography. Different from the coaxial interaction with spreading and recoiling one after another, the off-center interaction presents an asymmetric liquid motion featured by the concomitant spreading and recoiling. Rim thickness in recoiling decreases appreciably with increasing the offset distance. Results also show that the height of combined liquid is more representative of liquid oscillation than the diameter, based on which the interaction is grouped into four major phases: impingement phase, unsteady damped oscillation phase, steady damped oscillation phase, and static phase. Also presented in this study are maximum spreading diameter and minimum height of the combined liquid. This is followed by investigations of unsteady duration, oscillation period, and height profile with regards to Weber number and offset distance.

Ab initio molecular dynamics (AIMD) was applied to calculate the local structure and dynamics parameters of molten lead halides PbX2 (X = Cl, Br, I). The thoroughness of our approach is substantiated by the variation of both cell size and temperature. The total duration of AIMD runs amounted to 600 ps. It was found that molten lead chlorides exhibit weak binding of the local structure. The latter was analyzed by means of radial distribution functions for each pair of salt constituents. The radial distribution functions exhibit pronounced liquid-like damped oscillations and weakly depend on the cell size. In terms of vibrational properties, we highlight the frequencies of 125 cm−1 and 80 cm−1 which relate to the Pb-Br and Pb-I vibrations respectively, both of a short lifetime. These results are additionally supported by the calculated self-diffusion coefficients which concur closely with experimental values.

This work is part of our continuous research effort to reveal the underlying physics of bubble coalescence in microfluidics through the GPU-accelerated lattice Boltzmann method. We numerically explore the mechanism of damped oscillation in microbubble coalescence characterized by the Ohnesorge (Oh) number. The focus is to address when and how a damped oscillation occurs during a coalescence process. Sixteen cases with a range of Oh numbers from 0.039 to 1.543, varying in liquid viscosity from 0.002 to 0.08kg/(m · s) correspondingly, are systematically studied. First, a criterion of with or without damped oscillation has been established. It is found that a larger Oh enables faster/slower bubble coalescence with/without damped oscillation when (Oh 0.477) and the fastest coalescence falls at Oh ≈ 0.477. Second, the mechanism behind damped oscillation is explored in terms of the competition between driving and resisting forces. When Oh is small in the range of Oh

This paper proposes a method for detection and estimation of the characteristics of defects in concrete structures using laser ablation-induced vibration for non-contact structural inspection to prevent partial spalling. Two types of lasers are used: the first is an impact laser that is used to induce vibrations in the measurement target and the second is a detection laser that is used to measure these induced vibrations. Laboratory tests are performed using concrete specimens with and without an internal defect. The results show that the presence of a defect can be estimated from the occurrence of damped oscillations in the measurement data. The presence or absence of these damped oscillations can be determined using the least-squares complex frequency-domain (LSCF) method, which is a fast-stabilizing parameter estimation method for modal identification problems. Additionally, when a defect is present, the defect vibration characteristics, such as natural frequencies and damping ratios, can be estimated. In particular, the natural frequencies can be estimated accurately.

The average voidage, radial voidage and axial voidage distribution in ellipsoidal pellets bed layer were studied by experiments and Discrete Element Method (DEM) Simulation. A series of experiments were used to determine the collision parameters of DEM model. The influence of the bed geometry factor on the average voidage and the radial voidage of the bed layer were investigated, the distribution of axial voidage in the bed was observed under different bed height conditions. The results show that the pellet diameter and cylinder diameter are the critical factor affecting the bed voidage distribution. With the bed geometry factor increasing, the average voidage of the bed gradually decreased. When D/dp > 50, the average voidage of the bed approaches to a constant (0.292). The damped oscillation of the radial voidage distributes from the wall toward the center of bed, and there is a maximum value near the wall. When the total height of the bed is constant, ignoring the influence of edge effect, the axial voidage increased gradually and eventually tends to be constant. With the gradual increase of the bed height, the change rate of the voidage and the axial voidage at the same height gradually decreased.

This paper presents detailed procedure for determining the formula for calculation Tribonacci sequence numbers with arbitrary initial numbers Ta,b,c,(n). Initial solution is based on the concept of damped oscillations of Lucas type series with initial numbers T3,1,3(n). Afterwards coefficient θ3 has been determined which reduces Lucas type Tribonacci series to Tribonacci sequence T0,0,1(n). Determined relation had to be corrected with a phase shift ω3. With known relations of unitary series T0,0,1(n) with remaining two equations of Tribonacci series sequence T1,0,0(n) and T0,1,0(n), Binet type equation of Tribonacci sequence that has initial numbers Ta,b,c(n) is obtained.

Time varying skewness ( S ) and kurtosis ( Q ) of height distribution of ( 2 + 1 ) -dimensional larger curvature (LC) model with and without noise reduction techniques (NRTs) are investigated in both transient and steady state regimes. In this work, effects of the multiple hit NRT ( m > 1 NRT) and the long surface diffusion length NRT ( l > 1 NRT) on the surface morphologies and characteristics of S and Q are studied. In the early growth time, plots of S and Q versus time of the m > 1 morphologies show pronounced oscillation indicating the layer by layer growth. Our results show that S = 0 and Q 0 at every half layer while S = 0 and Q > 0 at every complete layer. The results are confirmed by the same plots of the results from the Das Sarma–Tamborenea (DT) model. The l > 1 LC model, on the other hand, has no evidence of the layer by layer growth mode due to the rapidly damped oscillation of S and Q . In the steady state, the m > 1 and l > 1 NRTs affect weakly on the values of S and Q and the mounded morphologies of the film. This lead to the evidence of universality of S and Q in the steady state of the LC models with various m and l . The finite size effect on the values of S and Q is found to be very weak in the LC model. By extrapolating to L → ∞ , we obtain S L → ∞ ≈ 0.05 and Q L → ∞ ≈ − 0.62 which are in agreement with the NRTs results.

The study of low latitude damped Pi2 oscillations (40–150 s) are investigated using archived data from Choutuppal (CPL), geomagnetic observatory, operated by CSIR-NGRI, Hyderabad, India. The period of investigation is during solar cycle 21 (1975–1983). All the Pi2 events identified during this period are subjected to detailed analysis for their association with substorm and non-substorm events. It is interesting to note that there is equal probability of occurrence of Pi2s with or without a substorm. The Pi2 frequencies associated with substorms showed an increased value in the post-midnight sector than compared to the Pre-midnight sectors. The non-substorm Pi2s are seen to be associated with lower levels of geomagnetic activity. The corresponding period of Pi2s decreases with increasing level of activity. While the generation of Pi2s are generally attributed to substorm onset, it is seen that the quiet time non-substorm events are related to plasmaspheric cavity mode resonances at low latitudes.

In a previous study (Salazar and Perez Alcazar, 2015) we obtained the modified Landau–Lifshitz–Gilbert equation. The modification consisted in proposing a method to convert to symmetrical the kinetic coefficients of this equation. In the present study we find the solution to the proposed equation. This solution shows that the Mx and My components of the magnetization have damped oscillations. We find the expressions for the damping coefficient and the frequency of the oscillations and show their graphs. Finally, we compare these graphs with those that correspond to the frequency of oscillations for the magnetization in the Landau–Lifshitz–Gilbert equation.

Considering that a majority of lightning surges intruding into substations present non-standard form, an experimental study is performed on the q - u (charge-voltage) curves under damped oscillation impulses in a corona cage. Based on the measured results, a comparison is made between the q - u curves under damped oscillation and double exponential impulses. The oscillation frequency and damping time constant are varied to investigate their effect on the characteristic parameters of the q - u curves. A preliminary discussion is also given for explanation of the formative mechanism of the oblate helix minor loops appearing on the q - u curves.

Musculo-articular stiffness (MAS) of the triceps surae can be assessed using the free-oscillation technique whereby an impulse is applied and the ensuing damped oscillations are recorded. The purpose of this study was to investigate if impulses of different magnitudes can affect the measurement of MAS. Twenty seven males (20.7±1.3 years) participated in this study. Three impulses of different magnitude (1.5, 2.3 and 3.1Ns) and four different loads (10, 20, 30, 40kg) were employed in the assessment of triceps surae MAS, which was quantified and compared across loads and perturbations. As the magnitude of the impulse applied increased, the MAS (p

Spanish Abstract: El objetivo de este trabajo es presentar de manera detallada los modelos matematicos de Frisch y Kalecki, mostrando los problemas conceptuales y analiticos que la literatura reciente ha senalado. La linealizacion del sistema de ecuaciones de los modelos de Frisch y Kalecki, fortalecieron la idea de que los ciclos economicos se podrian explicar mediante un mecanismo de propagacion de oscilaciones amortiguadas y uno de impulso de choques externos aleatorios, mientras que el ciclo auto-sostenido de manera endogena encontraria su fundamento en la no linealidad English Abstract: The aim of this paper is to present in detail the mathematical models of Frisch and Kalecki, showing the conceptual and analytical problems that recent literature has pointed out. The linearization of the system of equations of the Frisch and Kalecki models strengthened the idea that economic cycles could be explained by a mechanism of propagation of damped oscillations and one of impulse of random external shocks, while the self-sustained cycle of endogenous way would find its foundation in non-linearity.

The objective of this paper is to investigate the structural response of carbon fiber sandwich panels subjected to blast loading through an integrated experimental and numerical approach. A total of nine experiments, corresponding to three different blast intensity levels were conducted in the 28-inch square shock tube apparatus. Computational models were developed to capture the experimental details and further study the mechanism of blast wave-sandwich panel interactions. The peak reflected overpressure was monitored, which amplified to approximately 2.5 times of the incident overpressure due to fluid-structure interactions. The measured strain histories demonstrated opposite phases at the center of the front and back facesheets. Both strains showed damped oscillation with a reduced oscillation frequency as well as amplified facesheet deformations at the higher blast intensity. As the blast wave traversed across the panel, the observed flow separation and reattachment led to pressure increase at the back side of the panel. Further parametric studies suggested that the maximum deflection of the back facesheet increased dramatically with higher blast intensity and decreased with larger facesheet and core thickness. Our computational models, calibrated by experimental measurements, could be used as a virtual tool for assessing the mechanism of blast-panel interactions, and predicting the structural response of composite panels subjected to blast loading.

Forty-three years ago, Kok and coworkers introduced a phenomenological model describing period-four oscillations in O 2 flash yields during photosynthetic water oxidation (WOC), which had been first reported by Joliot and coworkers. The original two-parameter Kok model was subsequently extended in its level of complexity to better simulate diverse data sets, including intact cells and isolated PSII-WOCs, but at the expense of introducing physically unrealistic assumptions necessary to enable numerical solutions. To date, analytical solutions have been found only for symmetric Kok models (inefficiencies are equally probable for all intermediates, called “S-states”). However, it is widely accepted that S-state reaction steps are not identical and some are not reversible (by thermodynamic restraints) thereby causing asymmetric cycles. We have developed a mathematically more rigorous foundation that eliminates unphysical assumptions known to be in conflict with experiments and adopts a new experimental constraint on solutions. This new algorithm termed STEAMM for S-state Transition Eigenvalues of Asymmetric Markov Models enables solutions to models having fewer adjustable parameters and uses automated fitting to experimental data sets, yielding higher accuracy and precision than the classic Kok or extended Kok models. This new tool provides a general mathematical framework for analyzing damped oscillations arising from any cycle period using any appropriate Markov model, regardless of symmetry. We illustrate applications of STEAMM that better describe the intrinsic inefficiencies for photon-to-charge conversion within PSII-WOCs that are responsible for damped period-four and period-two oscillations of flash O 2 yields across diverse species, while using simpler Markov models free from unrealistic assumptions.

By combining the simplified shooting method with a sandwich method, the existence and nonexistence of two types of traveling wave solutions for a class of diffusive predator–prey systems with general functional response are investigated. These two types of point-to-point traveling waves include the connections of the zero equilibrium to the positive equilibrium and the boundary equilibrium to the positive equilibrium. Furthermore, we also give a discussion about the parameter threshold value whether any of the traveling waves approaches the positive equilibrium monotonically or has exponentially damped oscillations about the positive equilibrium. Some applications with different functional response functions are given to illustrate the application of our results.

Robustness in complex networks is an ongoing research effort that seeks to improve the connectivity of networks against attacks and failures. Among other measures, algebraic connectivity has been used to characterize processes such as damped oscillation of liquids in connected pipes. Similar characterizations include the number of edges necessary to disconnect a network: the larger the algebraic connectivity, the larger the number of edges required to disconnect a network and hence, the more robust a network. In this paper, we answer the question, ''Which edge can we rewire to have the largest increase in algebraic connectivity?''. Furthermore, we extend the rewiring of a single edge to rewiring multiple edges to realize the maximal increase in algebraic connectivity. The answer to this question above can provide insights to decision makers within various domains such as communication and transportation networks, who seek an efficient solution to optimize the connectivity and thus increase the robustness of their networks. Most importantly, our analytical and numerical results not only provide insights to the number of edges to rewire, but also the location in the network where these edges would effectuate the maximal increase in algebraic connectivity and therefore, enable a maximal increase in robustness.

Biologically motivated mathematical models, which describe the dynamics of thrombocytopoiesis and granulocytopoiesis in nonirradiated and irradiated humans, are developed. These models, being based on conventional biological theories, are implemented as the systems of nonlinear differential equations whose variables and constant parameters have clear biological meaning. Thorough analytical and numerical analysis of the proposed models is performed. It is found that the models on hand are capable of reproducing the dynamical regimes which are typical for the thrombocytopoiesis and granulocytopoiesis in the norm and in the case of hematological disorders, such as cyclic thrombocytopenia and cyclic neutropenia. The elaborated models are applied to investigate the dynamics of thrombocytopoiesis and granulocytopoiesis in astronauts exposed to space radiation during long-term missions such as voyages to Mars. The dose rate equivalent for space radiation (galactic cosmic rays (GCR) and solar particles event (SPE)) is taken as a variable parameter of the models. It is revealed that the thrombocytopoietic and granulocytopoietic systems can adapt themselves to GCR exposure. It is also shown that an SPE causes damped oscillations of the “effective” radiosensitivity of these cell systems that, in turn, determines the strength of their responses to the subsequent SPE. Specifically, depending on the time interval between SPEs, the preceding SPE can induce either radiosensitization or radioprotection effects on the thrombocytopoietic and granulocytopoietic systems. In the last case, adaptive responses to the subsequent SPE in these systems occur. All this testifies to the efficiency of employment of the developed models in investigation and prediction of effects of space radiation on the thrombocytopoietic and granulocytopoietic systems. The developed models of these vital body systems provide a better understanding of the risks to health from the solar particles events and enable one to evaluate the need of operational applications of countermeasures for astronauts in the long-term space missions.

Coupling properties of two gain-guided index-antiguided (GG + IAG) fibers or GG+IAG fibers and index-guided (IG) fibers were investigated by the further general coupled mode theory The theory can explain any situation of two fiber coupling The interesting results were obtained by the numerical computation method For two GG + IAG fiber coupling total power was decreased as rising real-valued refractive-index difference (real part of refractive-index difference between core and cladding RVRID) while the power of one GG + IAG fiber was damped oscillations with Increased core separation In the GG + IAG fiber and IG fiber coupler the variation of the RVRID could change coupling characteristics These results are different from two IG fibers coupling and the general coupled-mode theory may provide meaningful references for new concepts of directional coupler and pumping technology of GG+IAG fiber Crown Copynght (C) 2010 Published by Elsevier BV All rights reserved

A fast-rise trial has been performed using auxiliary magnets, which are excited by damped oscillation. There is a possibility to achieve faster rise-time using a simple structure than a delayed line type magnet. A favorable result was obtained by the method. The outline of this scheme and the representative experimental results are described in this paper.

Spectrograms and ELF power spectra of magnetic variations originated from sprite-producing lightning discharges have been analyzed to extract both parent lightning and sprite parameters. Some of the spectrograms and power spectra have been found to have approximately quasi-oscillatory shape in the frequency range 0–40 Hz with maximum repetition period about 15–20 Hz. A theory predicts that this interesting peculiarity of the power spectra can be due to interference between electromagnetic fields originated from the parent lightning discharge and from the sprite. A smooth envelope of the power spectrum was shown to have a form of damped oscillations with period close to reciprocal value of sprite lag time. A technique of extracting sprite parameters based on the sprite-producing lightning power spectrum is proposed. The lack of the first Schumann resonance and other features occasionally observed in spectral resonance structure were also discussed.

There are only three qualitative values positive, negative and zero. This means that there is a maximal number of qualitatively distinguishable scenarios, prescribed by the number of variables and the highest qualitative derivative taken into consideration. There are several chaos related tasks, which can be solved with great difficulties on the numerical level if multidimensional problems are studied. One of them is the identification of all qualitatively different behaviours. To make sure that all distinctive qualitative scenarios are identified a qualitative interpretation of a classical quantitative phase portrait is used. The highest derivatives are usually the second derivatives as it is not possible to safely identify higher derivatives if tasks related to ecology or economics are studied. Two classical models are discussed – Damped oscillation (non chaotic) and Lorenz model (chaotic). There are 191 scenarios of the Lorenz model if only the second derivatives are considered. If the third derivatives are taken into consideration then the number of scenarios is 2619. Complete qualitative results are given in details.

In this paper, we explore the dynamic properties of an endogenous growth model with finite patent length. We show that there exists a unique equilibrium growth path and that this path exhibits damped oscillations in contrast to the equilibrium path of an endogenous growth model with infinite patent length. We also examine the effects of patent policy on social welfare and show that infinite patent length does not maximize social welfare. Furthermore, we show that, in a growth model that does not exhibit scale effects, a finite patent length maximizes social welfare on the balanced growth path.

In this paper, we discuss the generalization of a recently developed perturbation method for conservative single degree of freedom systems to the cases of damping forces. We show that by explicitly considering the solution as a function of the amplitude parameter, frequency and phase of oscillation, one can merge the classical Krylov–Bogoliubov–Mitropolsky method and a modified Lindstedt–Poincare method to derive better accurate slow-flow for damped oscillation of single degree of freedom systems.

The spike-triggered average voltage (STV) is an experimentally measurable quantity that is determined by both the membrane response properties and the statistics of the synaptic drive. Here, the form of the STV is modelled for neurons with three distinct types of subthreshold dynamics; passive decay, h-current sag, and damped oscillations. Analytical expressions for the STV are first obtained in the low-noise limit, identifying how the subthreshold dynamics of the cell affect its form. A second result is then derived that captures the power-law behaviour of the STV near the spike threshold.

BWR core-wide stability is studied from the viewpoint of linear dynamic stability treated via poles of a closed-loop transfer function. The quantitative study is performed using a BWR noise model describing neutronic and thermal-hydraulic core dynamics. Transfer functions of neutron power to reactivity and core inlet flow are derived in explicit forms and their poles are evaluated both numerically and analytically. It is shown that the characteristic poles may be classed into three groups relating to neutronic process, fuel heat transfer and core void dynamics. In particular, the poles for the void dynamics take complex values and hence give rise to core-wide damped oscillation of neutron power. Furthermore, the study of characteristic poles serves for the stability analysis of the Ringhals-1 benchmark test data. It is shown and clarified that two stability indexes, decay ratio and resonance frequency, have clear dependence on reactor power and core inlet flow.

SummaryThe cell-cycle oscillator includes an essential negative-feedback loop: Cdc2 activates the anaphase-promoting complex (APC), which leads to cyclin destruction and Cdc2 inactivation. Under some circumstances, a negative-feedback loop is sufficient to generate sustained oscillations. However, the Cdc2/APC system also includes positive-feedback loops, whose functional importance we now assess. We show that short-circuiting positive feedback makes the oscillations in Cdc2 activity faster, less temporally abrupt, and damped. This compromises the activation of cyclin destruction and interferes with mitotic exit and DNA replication. This work demonstrates a systems-level role for positive-feedback loops in the embryonic cell cycle and provides an example of how oscillations can emerge out of combinations of subcircuits whose individual behaviors are not oscillatory. This work also underscores the fundamental similarity of cell-cycle oscillations in embryos to repetitive action potentials in pacemaker neurons, with both systems relying on a combination of negative and positive-feedback loops.

A two-level atom is put into a cavity comprising a transparent dielectric with one-side output coupling. An analytical expression of the time-dependence Casimir–Polder force in such a system is obtained. Our results show that the force finally tends to a steady negative value after a short-time damped oscillation. The effects on the force of the relative dielectric constant and the cavity size are also discussed in detail, respectively.

In this Letter we study director oscillation under the influence of elastic deformations in a nematic liquid crystal with homeotropic boundary conditions. The director oscillations are obtained by solving the field equation corresponding to splay, twist and bend deformations. The director fluctuation is found to be mostly governed by damped oscillations.

A review is presented on the advances in understanding equilibration phenomena in compressible pure fluids near the liquid–vapor critical point. The important role of the piston effect is stressed. The equilibration of temperature and density of a fluid sample, kept in a constant volume, are described. Examples are given both above and below the critical point under Earth's gravity (1 g) and microgravity conditions. The good agreement between experimental results and simulations demonstrate the present understanding of the process. The convection onset of a compressible pure fluid in a Rayleigh–Benard cell at 1 g is described. The impact of the piston effect on the transient, which leads to damped oscillations on the way to reaching a steady state convection, is also described. Here again the results of experiments and numerical simulations are compared. To cite this article: H. Meyer, F. Zhong, C. R. Mecanique 332 (2004).

An experimental capillary pumped loop (CPL) device has been developed in order to study its fundamental response mechanisms following steps of applied power. A global model including all the loop elements and the essential physical processes has been designed, with a sole control parameter for fitting experiments and simulations. By comparing experimental results and simulations for upward and downward steps of heat load, the response mechanisms within the loop can be analyzed. This analysis has revealed a particularly good agreement for damped oscillations of low frequency observed during the undershoots; it also provides an explanation as to the two-phase loop reacts badly to abrupt decreases of applied power.

Using the analytic modified EAM potentials, the surface concentrations and concentration depth profiles of (111) and (10 0) faces of Pt-Pd and Pt-Ir binary alloys are studied with Monte Carlo simulation based on the grand canonical ensemble statistical rule. In Pt-Pd alloy, the topmost surface is enriched with Pd, and the subsurface layer is depleted of Pd. The simulation results show a damped oscillation of Pd concentration in the whole composition range. A strong Pd segregation is observed for both the orientation faces, while the amount of Pd segregation in the (I 11) face is significantly less than that in the more open (10 0) face. However, Pt segregates to the surface strongly in the Pt-Ir alloy, and the amount of Pt segregation in the (10 0) and (I 11) face is almost the same. The simulation results are in good agreement with the available experiment data and other theoretical values. (C) 2002 Elsevier Science B.V. All rights reserved.

Revealing the role of bursts of action potentials is an important step toward understanding how the neurons communicate. The dominant point of view is that bursts are needed to increase the reliability of communication between neurons [Trends Neurosci. 20 (1997) 38]. In this paper we present an alternative but complementary hypothesis. We consider the effect of a short burst on a model postsynaptic cell having damped oscillation of its membrane potential. The oscillation frequency (eigenfrequency) plays a crucial role. Due to the subthreshold membrane resonance and frequency preference, the responses (i.e. voltage oscillations) of such a cell are amplified when the intra-burst frequency equals the cell's eigenfrequency. Responses are negligible, however, if the intra-burst frequency is twice the eigenfrequency. Thus, the same burst could be effective for one cell and ineffective for another depending on their eigenfrequencies. This theoretical observation suggests that, in addition to coping with unreliable synapses, bursts of action potentials may provide effective mechanisms for selective communication between neurons.

The spectrum of gravitational waves emitted after the formation of a black hole is dominated by damped oscillations, or ringing tones, represented by quasinormal modes. An analogy with the natural frequencies of a bell is quite fitting, since any system with a continuous spectrum permits complex frequency resonances. Some applications of spectral techniques are considered here and the following question is posed: to what extent is the geometry determined by the quasinormal mode spectrum?

An anomalous time dependent optogalvanic (OG) response detected in Ne/As hollow cathode discharge is analysed. The observed damped oscillation is shown to be close in form to a partial solution of the proposed time dependent equation describing the optogalvanic circuit. This oscillating solution takes place for negative dynamic resistance of the OG detector. It was found that the measured i – V curves contain negative resistance parts. The stability of the OG circuit to disturbances at negative resistance is analysed relative to slope steepness of the dynamic resistance and other circuit parameters.

Single-enzyme systems can undergo weakly damped concentration oscillations if the enzyme can be converted to an inactive form which only slowly reverts to the active form. Inactivation can take many forms, including a simple (hysteretic) conformational change of the enzyme. This observation may provide an explanation for the damped oscillations seen in photosynthetic activity following a sudden disturbance since rubisco, the enzyme responsible for fixing carbon, is a hysteretic enzyme with appropriate kinetic constants for oscillation. Copyright 1998 Academic Press

Small, quasi-rhythmical tremor of the jaw occurs at rest and during voluntary movements. In peripheral limbs, tremor consists of a component due to mechanical resonance properties of the system, and a neurogenic component mediated by a central pacemaker or neural loops. The present study attempted to determine if these components were present in jaw tremor measured with a position transducer held lightly between the incisors. When weights were suspended from the mandible, the tremor frequency was unaltered; sharp taps delivered to the jaw did not elicit any kind of damped oscillations of the system. These findings indicated the absence of mechanical resonance in the system. No correlation of the tremor signal with the electrocardiogram was found. However, a strong correlation was found between the rectified electromyographic signals recorded over the masseter muscles and the tremor signal, where the electromyographic signal preceded jaw movement by 20-30 msec. Frequency-domain analysis also showed positive peaks in a majority of coherence functions between electromyographic and tremor signals. These results suggested a strong neurogenic component of the tremor.

Zero field μSR measurements on CeRu2(Ge1−xSix)2 for x = 0 , 0.125, 0.25 and 0.5 show damped oscillations in the low-temperature-ordered phases. For x = 0.125 , 0.25 two distinct regimes are found in the temperature dependence of the oscillation frequency, corresponding to sinusoidally modulated magnetic order and ferromagnetism.

In this paper, we propose several distinct, but related, approaches to the analysis of microtubular assembly and disassembly phenomena. Individual microtubules are modelled using stochastic maps. We then indicate a possible route to continuous evolution equations of the Fokker-Planck type. Finally, chemical kinetics phenomenology is employed to simulate damped oscillations of microtubule ensembles for high tubulin concentrations. A comparison with experimental data is shown to support the presented models.

The optogalvanic effect is studied in a subnormal electrical glow discharge. In this discharge's regime the optogalvanic signal presents a damped oscillation characteristic with frequency, damping coefficient and amplitude modulation that are independent of the particular transition excited. The experimental results are interpreted by modelling the discharge as an optoelectronic transducer.

A linear stability analysis of the Tang, Statz and deMars equations describing a multimode laser in the antiphase regime is performed. It is shown that when all gains are equal, the systems is characterized by two damped oscillation frequencies. As the modal gains become different, the lowest of the two frequencies splits into as many frequencies as there are different gains. All these modes have the same linewidth which scales like the total lasing intensity.

In this paper the non-linear damped oscillations of moderately thick plates have been analysed by using the method of “constant deflection contour lines” and the well-known Berger method. Numerical results both for circular and elliptic plates have been computed and compared with other known results.

Three commercial photovoltaic panels based on single crystal silicon solar cells are investigated. Two types of transients are observed: instantaneous short-circuiting and instantaneous open-circuiting. It is shown that the transient currents under short-circuiting have a character of damped oscillations and the transient voltages under open-circuiting rise exponentially for all types of solar cell panels. The currently used equivalent diagrams cannot explain the results obtained.

The purpose of the investigation is to correlate the experimental data of Roblee et al. (1958) Brosilow (1959), Benenati and Brosilow (1962) and Ridgway and Tarbuck (1966) to produce an empirical model which consists of one principal equation for the radial porosity distribution and includes the damped oscillations. The radial porosity model is correlated in terms of the diameter aspect ratio and a non dimensional distance from the container wall. The model can be used in analytical transport models for simulating packed beds of uniform spheres in cylindrical containers

The nuclear-cytoplasmic shuttling of NF-κB is characterized by damped oscillations of the nuclear concentration with a time period of around 1.5 hours. The NF-κB network contains several feedback loops modulating the overall response of NF-κB activity. While IκBα is known to drive and IκBe is know to dampen the oscillations the precise role of A20 negative feedback remains to be elucidated. Here we propose a reduced model of the NF-κB system focusing on three negative feedback loops (IκBα, IκBe and A20) which capture the experimentally observed responses in wild-type and knockout cells. We find that A20, like IκBe, efficiently dampens the oscillations although through a distinct mechanism. In addition however we have discovered a new functional role of A20 by which it controls the oscillation period of nuclear NF-κB. The design based on three nested feedback loops allows an exploration of different oscillatory responses where both period and amplitude decay can be modified. Based on these results we predict that adjusting the expression level of A20, by e.g. siRNA, the period can be changed from 1h to 3h.

Tone and biomechanical properties of muscles can be measured objectively, e.g., using a probe that applies a perpendicular brief pulse percussion to the underlying tissue. The tissue responds in the form of damped oscillations that can be recorded by sensor measuring kinematic variations. We performed a double-blind study of 40 patients (15 M, 25F) affected by spasticity, who were treated with BoNT (72.45±23.52 Botox U). The patients were evaluated before and after treatment using the modified Ashworth score (MAS); muscle tone, elasticity and stiffness were evaluated using Myoton ® , either at rest or during passive extension. Follow-up evaluations were performed 25–30 days and 4 months after treatment. Variations in MAS and physical variables were compared using 2-way ANOVA. Muscle tone was reduced at rest and during passive elongation, both at 25–30 days and at 4 months, compared to baseline ( p p