Effect of cryoprotectants on hatching rate of red seabream (Pagrus major) embryos

The objectives were to investigate the effect of cryoprotectants on the hatching rate of red seabream embryos. Heart-beat embryos were immersed in: five permeable cryoprotectants, dimethyl sulfoxide (DMSO), glycerol (Gly), methanol (MeOH), 1,2-propylene glycol (PG), and ethylene glycol (EG). in concentrations of 5-30% for 10, 30, or 60 min; and two non-permeable cryoprotectants: polyvinylpyrrolidone (PVP), and sucrose (in concentrations of 5-20% for 10 or 30 min). The embryos were then washed and incubated in filtered seawater until hatching occurred. The hatching rate of the embryos treated with permeable cryoprotectants decreased (P < 0.05) with increased concentration and duration of exposure. In addition, PG was the least toxic permeable cryoprotectant, followed by DMSO and EG, whereas Gly and MeOH were the most toxic. At a concentration of 15% and 30 min exposure, the hatching rate of the embryos immersed in PG was 93.3 +/- 7.0% (mean +/- S.D.), however. in DMSO. EG, Gly. and MeOH, it was 82.7 +/- 10.4, 22.0 +/- 5.7, 0.0 +/- 0.0, and 0.0 +/- 0.0%, respectively. Hatching rate of embryos treated with PVP decreased (P < 0.05) with the increase of concentration and exposure time, whereas for embryos treated with sucrose, there was no significant decrease in comparison with the control at the concentrations used. (C) 2008 Elsevier Inc. All rights reserved.

Chemical Constituents from the Leaves and Stems of Schisandra lancifolia

A new nortriterpenoid, 20-hydroxymicrandilactone D (1) and a novel lignan glycoside, lancilignanside A (2) were isolated from leaves and stems of Schisandra lancifolia, together with three known nortriterpenoids (3—5) and nine known phenolics (6—14). The structures of new compounds 1 and 2 were determined by detailed analysis of their 1D and 2D NMR spectra, and chemical evidences. In addition, compounds 1—2, 6—7, and 9—11 showed anti-human immunodeficiency virus (HIV)-1 activities with 50% effective concentration (EC50) in the range of 3.0—99.0m g/ml. Compound 12 was not bioactive in this assay with EC50 more than 200m g/ml.

On-Chip All-Optical Passive 3.55 Gbit/s NRZ-to-PRZ Format Conversion Using a High-Q Silicon-Based Microring Resonator

We report the experimental result of all-optical passive 3.55 Gbit/s non-return-to-zero (NRZ) to pseudo-return-to-zero (PRZ) format conversion using a high-quality-factor (Q-factor) silicon-based microring resonator notch filter on chip. The silicon-based microring resonator has 23800 Q-factor and 22 dB extinction ratio (ER), and the PRZ signals has about 108 ps width and 4.98 dB ER.

一种实现光子晶体波导定向耦合型多路光均分的新方法

将多光子晶体单模波导平行、邻近放置构成定向耦合器. 依据自映像原理,数值分析了输入光场对称入射时,该系统中光的传播行为. 基于此结构,以三、四通道为例,设计了超微多路光分束器,并仅通过对称地改变耦合区中两个介质柱的有效折射率,使光场在横向发生重新分布,实现了输出能量的均分或自由分配. 和已报道结果相比,此调制方法更为简单易行而且效率更高,并可以推广到具有更多输出通道的光分束器中,在未来的集成光回路中具有广泛的应用价值.

AlGaInP LED with surface structure of two-dimensional photonic crystal

Some progress in the research of GaN based LED with photonic crystal structure has been made recently. Based on the photonic crystal's photonic band gap effect and photon grating diffraction principle, the extraction efficiency of LED with photonic crystal can be improved. In this paper, the restriction on AlGaInP LED's extraction efficiency is analyzed, and the photonic crystal is introduced in to the AlGaInP LED to improve the extraction efficiency. The theoretical analyses and the experiment results show that the output luminous intensity of LED with photonic crystal is improved by 16%, which results from some effect of the GaN based LED with photonic crystal.