Chinese date, the fruit of Ziziphus jujuba Mill., has thousands of years cultivation history, and about 700 cultivars of dates in China. Two types of dates are commonly found in the market: (i) fresh immature dates consumed as fruits, and (ii) dried mature dates used as Chinese medicines. Here, chemical and biological properties of these dates were revealed. Different sources of dates showed similar chemical profiles; however, the amounts of identified chemicals showed a great variation. The amount of nucleotides, flavonoids and polysaccharides in dates could be affected by its maturity and drying process. In parallel, the antioxidative functions of their extracts were compared. The date extracts protected PC12 cells against tBHP-induced cytotoxicity, and which also stimulated the transcriptional activity of antioxidant response element. The antioxidative effects were varied among different dates. The current results suggested the optimization of sources and specific usage of different maturity dates.

Abstract-We investigate nonlinear carrier dynamics in a multiquantum-well semiconductor optical amplifier (SOA) in the context of ultrafast all-optical logic. A rate-equation model is presented that accounts for two-photon absorption, free-carrier absorption, self-and cross phase modulation, carrier heating, spectral, spatial hole burning, and self-and cross polarization modulation. The nonlinear refractive index dynamics is investigated theoretically and experimentally. We find nonlinear phase changes larger than radians, which recovers on a timescale in the order of 1 ps. We also investigate a nonlinear AND gate that consists of an SOA that is placed in an asymmetric Mach-Zehnder interferometer. We show that the gate can be operated using 800-fJ optical pulses with duration of 200 fs while having a contrast ratio larger than 11 dB.Index Terms-Optical logic, optical signal processing ultrafast carrier dynamics, semiconductor optical amplifier.

Approximately 30 % of epilepsy cases are refractory to current pharmacological treatments through unknown mechanisms. Much work has been done on the role of synaptic components in the pathogenesis of epilepsy, but relatively little attention has been given to the potential role of the microtubules. We investigated the level of microtubule dynamic in 30 human epileptic tissues and two different chronic epilepsy rat models. The administration of microtubule-modulating agent attenuated the progression of chronic epilepsy. By contrast, microtubule-depolymerizing agent aggravated the progression of chronic epilepsy. The electrophysiological index by whole-cell clamp was used to investigate the neuronal excitation and inhibitory synaptic transmission in brain slices after administration of microtubule-modulating agent and microtubule-depolymerizing agent. Interestingly, we found that microtubule-modulating agent significantly increased the frequency of action potential firing in interneurons, and significantly promoted the amplitudes and frequencies of miniature inhibitory postsynaptic currents. Microtubule-depolymerizing agent had an opposite effect. These findings suggest that modulating hyperdynamic microtubules may take an anti-epileptic effect via postsynaptic mechanisms in interneurons. It could represent a potential pharmacologic target in epilepsy treatment.

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