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Effects of ZnO, CuO, Au, and TiO2 nanoparticles on Daphnia magna and early life stages of zebrafish danio rerio

Liu J., Fan D., Wang L., Shi L., Ding J., Chen Y., Shen S.

Environment Protection Engineering

2014

Vol. 40, nr 1

139--149

The effects of four different kinds of nanoparticles (NPs), namely, CuO, ZnO, TiO2, and Au, of the sizes ranging from <20 nm to 50 nm on Daphnia magna, early life stage of zebrafish, and various enzymes have been investigated. The experimental results showed that the NPs inhibited both the body length and hatching rate of zebrafish larvae; the small nanoparticles exhibited more toxicity. In a 21 day chronic toxicity test, metal ions of higher concentrations significantly reduced the number of Daphnia magna offspring. Studies on enzyme activity showed that the NPs reduced the glutathione content and inhibited catalase and superoxide dismutase activities, resulting in shorter body length, lower hatching success, and lower reproduction of zebrafish larvae. Therefore, studies should focus more on the potential toxicity of smaller NPs.

Basic research on determining optical properties of tissues in vivo by measuring diffuse reflectance with a charge-coupled device

Sun P., Cao X., Yang R., Xie F., Ding J., Zhang F.

Optica Applicata

2011

Vol. 41, nr 3

541--555

We measured the absorption coefficient and the reduced scattering coefficient of Intralipid solution and human forearm tissues in vivo by measuring diffuse reflectance with a charge-coupled device, examining the techniques involved. The experimental results indicate that the error is less than or equal to 8% using the diffusion theory, under the condition that the reduced scattering coefficient is one order of magnitude greater than the absorption coefficient. The stability and precision of optical property measurements are significantly improved by using the multistep iterative fitting method and using the ring-zone-constraint method to determine the diffuse reflectance center. The efficiency of reverse algorithm is greatly enhanced by selecting a one-dimensional array on the straight line crossing both the entry point and the diffusion center for fitting.

An important waypoint on passage of navigation history: Zheng He’s sailing to west ocean

Ding J., Shi Ch., Weintrit A.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

2007

Vol. 1, no. 3

285--294

Zheng He, a famous Chinese mariner, explorer, diplomat and fleet admiral of Ming Dynasty, sailed from China to many places throughout South Pacific, Indian Ocean, Bay of Bengal, Arabian Sea, Pesian Gulf, Red Sea and distant Africa in seven epical voyages from 1405 to 1433, some 80 years before Colubus’s voyages to America on Santa Maria. This magnificent feat in the history of navigation was later considered as a sheer waste of energy and money, and a “failure policy”. The scale of Zheng He’s navigation far exceeds that of Columbus’s “Great Discovery” which followed, but the former had less effect on the progress of the world history. In this paper, we recall Zheng He’s great adventure, as an important waypoint on the passage of navigation history. An introduction to the historical condition of that age and Zheng He’s family background is presented. The fleets, the passages, as well the experiences are illustrated. The shipbuilding technology and science of navigation of China in the ancient period are also demonstrated. And finally we discuss the historical significance, spirit and impact of Zheng He’s sailing. The great voyages are the magnificent landmarks not only in China’s political and diplomatic history but also in navigational annals of the world.