Bifurcations for counterintuitive post-inhibitory rebound spike related to absence epilepsy and Parkinson disease

Seizures are caused by increased neuronal firing activity resulting from reduced inhibitory effect and enhancement of inhibitory modulation to suppress this activity is used as a therapeutic tool.However,recent experiments have shown a counterintuitive phenomenon that inhibitory modulation does not suppress but elicit post-inhibitory rebound(PIR)spike along with seizure to challenge the therapeutic tool.The nonlinear mechanism to avoid the PIR spike can present theoretical guidance to seizure treatment.This paper focuses on identifying credible bifurcations that underlie PIR spike by modulating multiple parameters in multiple theoretical models.The study identifies a codimension-2 bifurcation called saddle-node homoclinic orbit(SNHOB),which is an intersection between saddle node bifurcation on invariant cycle(SNIC)and other two bifurcations.PIR spike cannot be evoked for the SNIC far from the SNHOBbut induced for the SNIC close to the SNHOB,which extends the bifurcation condition for PIR spike from the well-known Hopf to SNIC.Especially,in a thalamic neuron model,increases of conductance of T-type Ca^(2+)(TC a)channel induce SNIC bifurcation approaching to the SNHOB to elicit PIR spikes,closely matching experimental results of the absence seizure or Parkinson diseases.Such results imply that,when inhibition is employed to relieve absence seizure and Parkinson diseases related to PIR spike,modulating SNIC to get far from the SNHOBto avoid PIR spike is the principle.The study also addresses the complex roles of TCacurrent and comprehensive relationships between PIR spike and nonlinear conceptions such as bifurcation types and shapes of threshold curve.

Chinese textile and garment exports rebounded in March

According to data released by the General Ad­ministration of Customs on April 13th,China's textile and garment exports stopped falling and rebounded in March,which was more than that in February this year and the same period last year,and the overall export stabilized.

The Testing Strength Curves of Lightweight Aggregate Concrete by Rebound Method and Ultrasonic-rebound Combined Method

The strength curves of lightweight aggregate concrete （LWAC） were tested based on detecting LWAC with density of 1 400-1 900 kg/m3 and LWAC with strength grade of LC15-LC50 by rebound method and ultrasonic-rebound combined method.The results show that the common measured strength curves tested by above two methods can not satisfy the required accuracy of LWAC strength test.In addition,specified compressive strength curves of testing LWAC by rebound method and ultrasonic-rebound combined method are obtained,respectively.

Probability of rebound and eject of sand particles in wind-blown sand movement

When incident particles impact into a sand bed in wind-blown sand movement, rebound of the incident particles and eject of the sand particles by the incident particles affect directly the development of wind sand flux. In order to obtain rebound and eject lift-off probability of the sand particles, we apply the particle-bed stochastic collision model presented in our pervious works to derive analytic solutions of velocities of the incident and impacted particles in the postcollision bed. In order to describe randomness inherent in the real particle-bed collision, we take the incident angle, the impact position and the direction of resultant action of sand particles in sand bed on the impacted sand particle as ran- dom variables, and calculate the rebound and eject velocities, angles and coefficients （ratio of rebound and eject velocity to incident velocity）. Numerical results are found in accordance with current experimental results. The rebound and eject liftoff probabilities versus the incident and creeping velocities are predicted.

Level set method for numerical simulation of a cavitation bubble,its growth, collapse and rebound near a rigid wall

A level set method of non-uniform grids is used to simulate the whole evolution of a cavitation bubble, including its growth, collapse and rebound near a rigid wall. Single-phase Navier-Stokes equation in the liquid region is solved by MAC projection algorithm combined with second-order ENO scheme for the advection terms. The moving inter-face is captured by the level set function, and the interface velocity is resolved by ＂one-side＂ velocity extension from the liquid region to the bubble region, complementing the second-order weighted least squares method across the interface and projection inside bubble. The use of non-uniform grid overcomes the difficulty caused by the large computational domain and very small bubble size. The computation is very stable without suffering from large flow-field gradients, and the results are in good agreements with other studies. The bubble interface kinematics, dynamics and its effect on the wall are highlighted, which shows that the code can effectively capture the ＂shock wave＂-like pressure and velocity at jet impact, toroidal bubble, and complicated pressure structure with peak, plateau and valley in the later stage of bubble oscillating.

Numerical study on maximum rebound ratio in blasting wave propagation along radian direction normal to joints

In the process of 2-D compressional wave propagation in a rock mass with multiple parallel joints along the radian direction normal to the joints, the maximum possible wave amplitude corresponding to the points between the two adjacent joints in the joint set is controlled by superposition of the multiple transmitted and the reflected waves, measured by the maximum rebound ratio. Parametric studies on the maximum rebound ratio along the radian direction normal to the joints were performed in universal distinct element code. The results show that the maximum rebound ratio is influenced by three factors, i.e., the normalized normal stiffness of joints, the ratio of joint spacing to wavelength and the joint from which the wave rebounds. The relationship between the maximum rebound ratio and the influence factors is generalized into five charts. Those charts can be used as the prediction model for estimating the maximum rebound ratio.

EFFECTS OF DESENSITIZATION AND REBOUND TO ADENOSINE ON ACTION POTENTIAL AND CONTRACTILITY IN ATRIAL CELLS IN GUINEA-PIGS

Objective To investigate the effects of desensitization and rebound to adenosine(Ado) on action potential duration(APD) and contractility in guinea-pig atrial cells. Methods Electrical activity was recorded using standard intracellular microelectrode technique and contractility was recorded using. We studied the effects of adenosine on the action potential and desensitization of contractility and rebound of contractility. Results The results showed that action potential duration were shortened by 1,10, 100μ mol·L -1Ado, the ratio of shortened APD was ( 9.58± 1.40)%,(13.80±2.26)%,(24.80±3.19)%, respectively. 1 μ mol·L -1Ado had no desensitization ( P >0.05), but the time of desensitization of 10μ mol·L -1 Ado and 100μ mol·L -1 Ado was 1 minute( P <0.05) and 5 minutes( P < 0.05), respectively. The desensitization of contractility of 10?μ mol·L -1 Ado was obvious in atrial cells, the decrease of contractility of 10?μ mol·L -1 Ado was obvious in atrial cells, the decrease of contractility was changed from (31.4± 16.04)%(2 minutes) to (50.60±15.87)% (4 minutes), compared with control. After washing out Ado, contractility was shown to rebound, the ratio of increase of contractility by 1,10,100 μ mol·L -1 Ado was (12.38±7.50)%,(19.00± 8.14)% and (27.60±13.44)%, respectively. Conclusion Ado can abbreviate APD in atrial cells. The desensitization of Ado on APD is characterized by concentration-dependent and time-dependent in atrial cells, and the desensitization of contractility of Ado is obvious and contractility was shown to rebound after washing out Ado.

Rebound effect and its decomposition-an analysis based on energy types in China

Rebound effect derived from energy efficiency improvement has been widely invested.However,most of studies focus on the rebound effect of the energy composite level and neither distinguish nor compare different energy types.We compare the differences in energy saving and energy rebound between primary and secondary energy sources,and further decompose the rebound effect into production rebound part and final demand component.To do so,we add a module for rebound into a comparative state China-CGE model.We design and test two simulation scenarios using the model.In Scenario 1,all production sectors' energy efficiency of using primary energy increases by 5%.In Scenario 2,all production sectors' energy efficiency of using secondary energy increases by 5%.The results show that Scenario 2 leads to more GDP growth and more energy saving.Our scenarios show rebound effects range between 9.6% and 27.9%,and in general are higher when energy efficiency of using primary energy sources is improved.Our decomposition analysis shows that improving energy efficiency in production sectors would stimulates energy use of final demand.Indeed,the consumption side has significant contribution to rebound in secondary energy use,especially in crude oil and gas.This study reveals that improving efficiency of using secondary energy is better than improving that of primary energy,both in terms of economic impact and energy rebound.And complementary policies that prevent energy services prices from falling too much can be adopted to reduce rebound.Controlling residential energy use could also be effective in reducing rebound,this has particular implication to economies in which residential energy consumption are far from saturation.

Intraocular pressure measurement over soft contact lens by rebound tonometer: a comparative study

AIM: To evaluate the intraocular pressure(IOP)measurements by Icare rebound tonometer over a contact lens in comparison with Goldmann applanation tonometry(GAT). METHODS: Fifty patients using contact lens were included in this study. One of the eyes of the patients was selected randomly and their IOP were measured by rebound tonometer with and without contact lens(RTCL,RT respectively) and by GAT, as well as their central corneal thickness(CCT) by optical pachymeter. The results of both methods were compared by correlation analysis, general linear method repeated measure and Bland-Altman analysis.RESULTS: Mean IOP values measured by RTCL, RT and GAT were 15.68 ±3.7, 14.50 ±3.4 and 14.16 ±2.8(P 【0.001), respectively. Mean IOP by RTCL was significantly higher than the measurements implemented by RT and GAT(P 【0.001), while there was no difference between the measurements by GAT and RT(P =0.629). There was a good level of positive correlation between GAT and RTCL as well as RT(r =0.786 P 【0.001, r =0.833 P 【0.001, respectively). We have observed that CCT increase did not show any correlation with the differences of the measurements between RTCL and RT(P =0.329), RTCL and GAT(P =0.07) as well as RT and GAT(P =0.189) in linear regression model.CONCLUSION: The average of the measurements over contact lens by rebound tonometer was found to be higher than what was measured by GAT. Although this difference is statistically significant, it may be clinically negligible in the normal population.

Dynamics and rebound behavior analysis of flexible tethered satellite system in deployment and station-keeping phases

The tether deployment of a tethered satellite system involves the consideration of complex dynamic properties of the tether,such as large deformation,slack,and even rebound,and therefore,the dynamic modelling of the tether is necessary for performing a dynamic analysis of the system.For a variablelength tether element,the absolute nodal coordinate formulation(ANCF)in the framework of the arbitrary Lagrange-Euler(ALE)description was used to develop a precise dynamic model of a tethered satellite.The model considered the gravitational gradient force and Coriolis force in the orbital coordinate frame,and it was validated through numerical simulation.In the presence of dynamic constraints,a deployment velocity of the tether was obtained by an optimal procedure.In the simulation,rebound behavior of the tethered satellite system was observed when the ANCF-ALE model was employed.Notably,the rebound behavior cannot be predicted by the traditional dumbbell model.Furthermore,an improved optimal deployment velocity was developed.Simulation results indicated that the rebound phenomenon was eliminated,and smooth deployment as well as a stable state of the station-keeping process were achieved.Additionally,the swing amplitude in the station-keeping phase decreased when a deployment strategy based on the improved optimal deployment velocity was used.

Experimental study on prediction model for maximum rebound ratio

The proposed prediction model for estimating the maximum rebound ratio was applied to a field explosion test, Mandai test in Singapore. The estimated possible maximum peak particle velocities(PPVs) were compared with the field records. Three of the four available field-recorded PPVs lie exactly below the estimated possible maximum values as expected, while the fourth available field-recorded PPV lies close to and a bit higher than the estimated maximum possible PPV. The comparison results show that the predicted PPVs from the proposed prediction model for the maximum rebound ratio match the field-recorded PPVs better than those from two empirical formulae. The very good agreement between the estimated and field-recorded values validates the proposed prediction model for estimating PPV in a rock mass with a set of joints due to application of a two dimensional compressional wave at the boundary of a tunnel or a borehole.

Ball impacting and rebounding a lubricated surface covered by non Newtonian lubricant oil

Reynolds equation of a ball impacting and rebounding a lubricated surface covered by non Newtonian lubricant oil is derived, and numerical analysis are done.

Comparison of IOPen rebound tonometer with Goldmann applanation tonometer at different IOP levels

AIM:To compare the accuracy of IOPen rebound tonometer with Goldmann applanation tonometer(GAT) in individuals with low,normal and high intraocular pressure(IOP) and to evaluate the effect of central corneal thickness(CCT) on IOP measurements.METHODS:This cross-sectional study consisted of 159 participants.IOP of one eye of each subject was measured consecutively with IOPen and GAT.Then CCT was measured using an ultrasonic pachymeter.Based on GAT IOP readings,participants were divided into low,normal and high IOP groups.Correlation between tonometers and CCT was calculated by spearman’s correlation coefficient.Agreement between tonometers was evaluated using Bland-Altman method.RESULTS:Non-significant underestimation of IOP by IOPen was observed in low IOP group(Mean difference:0.20mmHg;P=0.454) and also in normal IOP group(Mean difference:0.56mmHg;P=0.065).However,IOPen significantly overestimated IOP in high IOP group(Mean difference:1.06mmHg;P=0.038).The 95% limits of agreement(LoA) width between IOPen and GAT IOPs were 7.84,8.57 and 14.27mmHg in low,normal and high IOP groups,respectively.Low IOP group had thinner corneas compared to high IOP group(P=0.034).IOP measurements taken by IOPen were not influenced by CCT(P=0.099) while poor correlation between CCT and GAT was found(R=0.17,P=0.032).Using receiver operating characteristic(ROC) curve,cutoff value of 18.75mmHg was determined for IOPen with sensitivity of 98.1 and specificity of 97.2%.CONCLUSION:Accuracy of IOPen is comparable to GAT in patients with low or normal IOP but IOPen overestimates IOP at high IOP levels.CCT does not affect IOP readings with IOPen.

Anti-rebound Cushion Device for Hydraulic Breaker

This paper analyzes the phenomenon of rebound impact and its negative influence on the present hydraulic breaker. To get over its shortcomings, a new anti-rebound cushion device has been designed to prevent the phenomenon of rebound impact. A hydraulic cushion is used to absorb the rebound impact energy, which can be released for the next stroke of the hydraulic breaker. Thus, there is little loss of energy, and the efficiency of the impact system can be increased by 5 %. The absorption effect of the hydraulic anti-rebound cushion increases the service life of breaker components by up to twice as long as in the current breaker. A dynamic model and a motion equation of the anti-rebound cushion device are presented, and the optimum frequency and damping ratio are obtained, providing optimum design parameters for the anti-rebound cushion device.

Energy Efficiency and Rebound Effect:Does Energy Efficiency Save Energy?

The aim of this study is to examine the theoric and empirical literature about “rebound effect”. This study summarizes energy efficiency policy and programs in general and in Turkey. Also it gives defination of the “rebound effect” concept. The rebound effect is related to consumer’s tendency to consume more energy due to economic benefit from efficiency improvement. The ‘rebound effect’ is the focus of a long-running dispute of energy economics but it is very new concept in the most developing countries. In literature according to some economist gains in energy efficiency will also reduce the real per unit price of energy services and hence the consumption of energy will rise and partially offset the initial reduction in the usage of energy sources. However for others size of the rebound effect is too small to take attention. The empirical literature shows that the size of rebound effect can change from country to country and sector to sector.

The rebound effect of dematerialization and decoupling:a case of energy efficiency

The two essential terms in environmental sciences-dematerialization and decoupling-have always been controversial. This study aims to trace the evolution path on the methodologies, the evidences and the policies, and to reflect on the implications of the development. We specifically present several classical definitions so as to summarize the similarities and differences thereinafter. Several commonly used methodologies, which are employed for evaluating the levels of dematerialization and decoupling, are discussed. As expected, the empirical evidences rarely support the absolute dematerialization and decoupling, which challenge the relevant policies implemented worldwide. In this context, the rebound effect, which is regarded as the main obstacle, is necessary to be examined in the various sectors and areas. However, the results of the rebound levels are far from unanimous. This article has a further discussion on the possible direction for the inconclusive debate in a broader perspective.

Continuous droplet rebound on heated surfaces and its effects on heat transfer property: A lattice Boltzmann study

A thermal multiphase lattice Boltzmann(LB) model is used to study the behavior of droplet impact on hot surface and the relevant heat transfer properties.After validating the correctness of the codes through the D^(2) law,the simulations of intrinsic contact angle and the temperature-dependent surface tension are performed.The LB model is then used to simulate the droplet impact on smooth and micro-hole heated surface.On the smooth surface,the impinging droplet is reluctant to rebound,unless the intrinsic wettability of the solid surface is fairly good.On the micro-hole surface,however,the micro-holes provide favorable sites for generating a high-pressure vapor cushion underneath the impinging droplet,which thereby facilitates the continuous droplet rebound.For the continuously rebounding droplet.The time evolution of volume and temperature display obvious oscillations.The achievable height of the rebounding droplet increases as the intrinsic wettability of the solid surface becomes better,and the maximum transient heat flux is found to be directly proportional to the droplet rebounding height.Within a certain time interval,the continuous rebounding behavior of the droplet is favorable for enhancing the total heat quantity/heat transfer efficiency,and the influence of intrinsic wettability on the total heat during droplet impingement is greater than that of the superheat.The LB simulations not only present different states of droplets on hot surfaces,but also guide the design of the micro-hole surface with desirable heat transfer properties.

Is Isostatic Rebound in Slow Spreading Gakkel Ridge of Arctic Region Due to the Climate Change? A Case Study

Ny-Alesund, Swalbard region which is located in the mid-ocean ridge of the Arctic Ocean, and named Gakkel ridge, is the slowest spreading ridge of the global system. In the present study an attempt has been made to associate isostatic rebound using GPS campaign data collected at Ny-Alesund area. The Artic Region Campaign GPS network was established in 2009. The network consists of three campaign mode station. The distance between GPS point is about ~30 km. The preliminary results of our investigation appear broadly consistent with the recent tectonic activity in western Svalbard. The resultant velocity vector is 14.84 mm·yr–1 with an azimuth of 27.67°N and a vertical displacement of 7.62 ± 3.0 mm·yr–1 is estimated in Swalbard, in which we presume Glacial Isostatic Rebound (5.1 mm·yr–1) and post glacial geological process (Present Day Ice Melting, erosion, and shore line deposits) of 2.52 mm per year in the study area.

Rebound Tonometry in Cataract Surgery: Comparison with Goldmann Applanation Tonometry

Purpose: to compare the rebound tonometer ICare? (RT) with the Goldmann applanation tonometer (GAT) in cataract surgery and to assess the influence of central corneal thickness (CCT) on intraocular pressure (IOP) measurements. Design: retrospective, comparative study. Methods: a total of 472 patients underwent IOP measurement using RT (time 0 = RTa). GAT IOP measurement was performed 5 minutes later, followed by a second RT IOP measurement after other 5 minutes (RTa + 10 min = RTb). CCT was obtained by ultrasound pachymetry. In 106 patients IOP was measured by means of RT and GAT before clear corneal cataract surgery (RT1 and GAT1) and at one day postoperatively (RT2 and GAT2). Results: RT IOP values > 5 mmHg were overestimated, while RT IOP values Conclusion: our results showed a good agreement between measurements obtained with RT and GAT in pre and postoperative cataract surgery, although a significant statistically difference was found between RT and GAT measurements performed postoperatively. Moreover, CCT is a parameter to be considered for the IOP measurement, especially for values obtained with RT.

China farm produce prices rebound slightly

Xinhua reported on May 2 that China’s farm produce prices mostly rebounded, ending a five-consecutive-week downward trend as persistent rainfall limited market supplies, new data has shown.