Recovery of the solitons using a lattice Boltzmann model

We formulate a lattice Boltzmann model which simulates Korteweg-de Vries equation by using a method of higher moments of lattice Boltzmann equation. Using a series of lattice Boltzmann equations in different time scales and the conservation law in time scale to, we obtain equilibrium distribution function. The numerical examples show that the method can be used to simulate soliton.

Effect of Co-administration of Morphine and Cholinergic Antagonists on Y-maze Spatial Recognition Memory Retrieval and Locomotor Activity in Mice

吗啡和胆碱能系统的相互作用已在多项研究中提到,本实验想查明吗啡是否能和胆碱能拮抗剂、东莨菪碱以及阿托品共同作用对小鼠的Y迷宫空间识别记忆提取产生影响.采用测试前腹腔给药的方法,选用3种剂量的吗啡(5、1.5、0.5mg/kg),两种剂量的东莨菪碱(1、0.1mg/kg),以及两种剂量的阿托品(0.5、0.1mg/kg),剂量由高到低相配对作为联合给药的手段.其结果表明:1)0.5mg/kg低剂量吗啡与0.1 mg/kg低剂量的东莨菪碱,或与0.1 mg/kg低剂最的阿托品联合给药的小鼠,在记忆提取测试中, 空间探查行为(各臂停留时间百分比)对新异臂没有偏好,而新奇探索行为(各臂访问次数百分比)仍保持了对新异臂的偏好,而相应剂最药物单独给药的小鼠记忆提取均没有被损害;2)吗啡能和东莨菪碱相互作用使小鼠的活动性显著增强.暗示吗啡和胆碱能拮抗剂对小鼠空间记忆提取的破坏存在一定程度的相互作用.

Effect of adrenalectomy and corticosterone replacement on prepulse inhibition and locomotor activity in mice

1 Stress is a risk factor in psychiatric illnesses such as schizophrenia. The aim of the present study was to investigate the effect of different circulating levels of the adrenal steroid corticosterone (CORT) on locomotor hyperactivity and prepulse inhibition of acoustic startle, two behavioural animal models of aspects of schizophrenia. 2 Male C57BL/6J mice (n = 10 per group) were anaesthetised with isoflurane and sham-operated or adrenalectomised (ADX). ADX mice were implanted with 50 mg pellets consisting of 100% cholesterol, or 2, 10 or 50 mg of CORT mixed with cholesterol. CORT pellet implantation dose dependently increased plasma CORT levels 3 weeks after surgery. Starting 1 week after surgery, mice were tested for prepulse inhibition after injection of saline or 5 mg kg(-1) of haloperidol. 3 In intact mice and in mice implanted with 10 mg of CORT, haloperidol treatment significantly increased prepulse inhibition (average values from 38 - 42 to 52%). Similar results were observed when testing the mice for amphetamine-induced locomotor hyperactivity (5 mg kg(-1)). In contrast, there was no significant effect of haloperidol in mice implanted either with cholesterol or 2 or 50 mg of CORT. 4 These results in behavioural animal models of schizophrenia suggest an important role of the stress hormone CORT in modulating dopaminergic activity in this illness.

Effects of dietary cyanobacteria of two different sources on growth and recovery of hybrid tilapia (Oreochromis niloticus x O. aureus)

A 115 days feeding trial was conducted to evaluate the effect of dietary cyanobacteria on growth, microcystins (MCs) accumulation in hybrid tilapia (Oreochromis niloticus x O. aureus) and the recovery when the fish were free of cyanobacteria. Three experimental diets were formulated: the control (cyanobacteria free diet); one test diet with cyanobacteria from Lake Taihu (AMt 80.0 mu g MCs g(-1) diet) and one with cyanobacteria from Lake Dianchi (AMd, 410.0 rho g MCs g(-1) diet). Each diet was fed to fish for 60 days and then all fish were free of cyanobacteria for another 55 days. A significant increase in feeding rate (FR) was observed in fish fed AMd diet after a first 30-day exposure (1(st) EP), and in fish fed both AMt diet and AMd diet after a second 30-day exposure (2(nd) EP). Specific growth rates (SGR) of fish fed AMt diet and AMd diet were both obviously affected after the first 30-day exposure, but SGR was only significantly affected in fish fed AMt diet after the second 30-day exposure. After a 55-day recovery, there were no significant differences among diets in the indices mentioned above. Much higher concentrations of MCs were accumulated in tissues of all fish exposed to cyanobacteria. After the 55-day recovery, MC concentrations in fish tissues were significantly lower than those on day 60. (C) 2009 Elsevier Ltd. All rights reserved.

Photosynthetic recovery of desiccated intertidal seaweeds after rehydration

Intertidal seaweeds experience periodical desiccation and rehydration to different extents due to the tidal cycles and their vertical distributions. Their photosynthetic recovery process during the rehydration may show different patterns among the seaweeds from different zonations or depths at intertidal zone. In this study 12 species of seaweeds collected from the upper, middle, lower and sublittoral zones were examined. The relationship of the photosynthetic recovery to vertical distribution was assessed by comparing their patterns of photosynthetic and respiratory performances after rehydration following desiccation. Both the photosynthesis and dark respiration declined during emersion, showing certain degrees of recovery after re-immersion into seawater for most species, but the extents were markedly different from one species to the other. The species from upper intertidal zone after being rehydrated for 1 hour, following 2 hours of desiccation, achieved 100 % recovery of their initial physiological activity, while most of the lower or sublittoral species did not achieve full recovery. It is the ability to withstand desiccation stress (fast recovery during rehydration), but not that to avoid desiccation (water retaining ability) that determines the distribution of intertidal seaweeds. Such physiological behavior during rehydration after desiccation reflects the adaptive strategy of intertidal seaweeds against desiccation and their capability of primary production in the process of rehydration.

Dried field populations of Nostoc flagelliforme (Cyanophyceae) require exogenous nutrients for their photosynthetic recovery

The effects of nutrients on the photosynthetic recovery of Nostoc flagelliforme during re-hydration were investigated in order to see if their addition was necessary. Net photosynthesis was negligible in distilled water without nutrient-enrichment. Addition of K+ resulted in significant enhancement of net photosynthesis, whereas other nutrients (Fe3+, Mg2+, Na+, NO3-, PO43-, Cl-) and trace-metals (A(5)) showed little effect. The recovered net photosynthetic activity increased with the increased K+, and reached the maximum at concentrations above 230 mu M. Desiccation and re-hydration did not affect the dependence of photosynthetic recovery on K+. It was concluded that dried field populations of N. flagelliforme require exogenous addition of potassium for photosynthetic recovery and that growth may be potassium-limited in nature.

Light dependency of the photosynthetic recovery of Nostoc flagelliforme

PS II photochemical efficiency (F-v/F-m) of Nostoc flagelliforme was examined after rewetting in order to investigate the light-dependency of its photosynthetic recovery. F-v/F-m was not detected in the dark, but was immediately recognized in the light. Different levels of light irradiation (4, 40 and 400 mu mol photon m(2) s(-1)) displayed different effects on the recovery process of photosynthesis. The intermediate level led to the best recovery of photochemical efficiency; the low light required longer and the high light inhibited the extent of the recovered efficiency. It was concluded that the photosynthetic recovery of N. flagelliforme is both light-dependent and influenced by photon flux density.

Investigation of gain recovery for InAs/GaAs quantum dot semiconductor optical amplifiers by rate equation simulation

The gain recoveries in quantum dot semiconductor optical amplifiers (QD SOAs) are numerically studied by rate equation simulation. Similar to the optical pump-probe experiment, the injection of double 150 fs optical pulses is used to simulate the gain recovery of a weak continuous signal under different injection levels, inhomogeneous broadenings, detuning wavelengths, and pulse signal energies for the QD SOAs. The obtained gain recoveries are then fitted by a response function with multiple exponential terms to determine the response times. The gain recovery can be described by three exponential terms with the time constants, which can be explained as carrier relaxation from the excited state to the ground state, carrier captured by the excited state from the wetting layer, and the supply of the wetting layer carriers. The fitted lifetimes decrease with the increase of the injection currents under gain unsaturation, slightly decrease with the decrease of inhomogeneous broadening of QDs, and increase with the increase of detuning wavelength between continuous signal and pulse signal and the increase of the pulse energy.

Coherence loss and recovery of an electron spin coupled inhomogeneously to a one-dimensional interacting spin bath: An adaptive time-dependent density-matrix renormalization group study

Coherence evolution and echo effect of an electron spin, which is coupled inhomogeneously to an interacting one-dimensional finite spin bath via hyperfine-type interaction, are studied using the adaptive time-dependent density-matrix renormalization group method. It is found that the interplay of the coupling inhomogeneity and the transverse intrabath interactions results in two qualitatively different coherence evolutions, namely, a coherence-preserving evolution characterized by periodic oscillation and a complete decoherence evolution. Correspondingly, the echo effects induced by an electron-spin flip at time tau exhibit stable recoherence pulse sequence for the periodic evolution and a single peak at root 2 tau for the decoherence evolution, respectively. With the diagonal intrabath interaction included, the specific feature of the periodic regime is kept, while the root 2 tau-type echo effect in the decoherence regime is significantly affected. To render the experimental verifications possible, the Hahn echo envelope as a function of tau is calculated, which eliminates the inhomogeneous broadening effect and serves for the identification of the different status of the dynamic coherence evolution, periodic versus decoherence.