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Evaluation of genetic diversity and population structure of five yellow catfish Pelteobagrus fulvidraco populations by microsatellite markers

Zhong L., Wang M., Pan J., Li D., Tang S., Bian W., Chen X.

Oceanological and Hydrobiological Studies

2018

Vol. 47, No. 2

99--106

Yellow catfish, Pelteobagrus fulvidraco, is an important commercial freshwater species in China. Knowledge about the genetic diversity of the yellow catfish is important to support the management and conservation programs, which would subsequently support the sustainable production of this species. To investigate the genetic diversity and the structure of yellow catfish in the middle and lower reaches of the Yangtze River, 125 individuals from five lakes were genotyped using 13 microsatellite markers. Moderate genetic diversity was determined in all populations, with the observed heterozygosity (HO) ranging from 0.42 to 0.49 and the expected heterozygosity (HE) ranging from 0.51 to 0.61. Low to moderate genetic differentiation among the populations was revealed from pairwise FST values (p < 0.05), as well as from analysis of molecular variance (AMOVA). The UPGMA dendrogram and Bayesian clustering analysis indicated a correlation between genetic differences and geographic distance – four populations from the lower reaches clustered together, whereas the Poyang Lake (PY) population formed a separate cluster. The present study would be helpful in the wild stock management and artificial propagation programs for yellow catfish in the middle and lower reaches of the Yangtze River.

A method for improving the precision of on-line phase measurement profilometry

Mao Z, Cao Y, Zhong L, Cao S

Optica Applicata

2015

Vol. 45, nr 1

51—61

An on-line phase measurement profilometry based on improved Stoilov’s algorithm is proposed to measure the 3D shape of moving object. While only one frame sinusoidal grating is projected on the moving object, the equal phase-shifting step deformed patterns modulated by profile of the measured object can be captured at every equivalent moving distance of the measured object instead of digital phase-shifting. Stoilov’s algorithm is an equal phase-shifting step algorithm at an arbitrary phase-shifting step, which is suitable for on-line phase measurement profilometry. However, the arbitrary phase-shifting step of Stoilov’s algorithm depends on the captured deformed patterns, in which the digitized errors of digital light projector or CCD camera, and the disturbance of surrounding light could be introduced, it will lead to some abnormities in wrapped phase, such as the denominator in Stoilov’s algorithm could be zero, which could cause the reconstructed 3D profile of the measured object appear burr, distortion or aberration, even could not be reconstructed. So an on-line phase measurement profilometry based on improved Stoilov’s algorithm is proposed. The arbitrary phase-shifting step is retrieved by both pixel matching and fringe cycle calibration rather than the captured deformed patterns. Experiments verify the feasibility and effectiveness of the proposed on-line phase measurement profilometry.

GaAs absorber grown at low temperature used in passively Q-switched diode pumped solid state laser

Wang Y., Ma X., Wang C.L., Lin T., Zhen K., Wang J., Zhong L., Jia Y., Wei Z.Y.

Optica Applicata

2006

Vol. 36, nr 1

23-28

We report, for the first time to the best of our knowledge, on a passively Q-switched Nd:YVO4 laser with a GaAs absorber grown at low temperature (LT) by metal organic vapor phase expitaxy. Using the LT GaAs absorber as well as an output coupler, a passively Q-switched laser whose pulse duration is as short as 90 ns was obtained.