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The giant panda ( Ailuropoda melanoleuca ) is among the more familiar symbols of species conser- vation. The protection of giant panda populations has been aided recently by the establishment of more and better-managed reserves in existing panda habitat located in six mountain ranges in western China. These re- maining populations are becoming increasingly isolated from one another, however, leading to the concern that historic patterns of gene flow will be disrupted and that reduced population sizes will lead to diminished genetic variability. We analyzed four categories of molecular genetic markers (mtDNA restriction-fragment- length polymorphisms (RFLP), mtDNA control region sequences, nuclear multilocus DNA fingerprints, and mi- crosatellite size variation) in giant pandas from three mountain populations (Qionglai, Minshan, and Qin- ling) to assess current levels of genetic diversity and to detect evidence of historic population subdivisions. The three populations had moderate levels of genetic diversity compared with similarly studied carnivores for all four gene measures, with a slight but consistent reduction in variability apparent in the smaller Qinling population. That population also showed significant differentiation consistent with its isolation since historic times. From a strictly genetic perspective, the giant panda species and the three populations look promising insofar as they have retained a large amount of genetic diversity in each population, although evidence of re- cent population reduction—likely from habitat loss—is apparent. Ecological management to increase habi- tat, population expansion, and gene flow would seem an effective strategy to stabilize the decline of this en- dangered species.

Emulsion graft copolymerization of poly(hydrogenmethylsiloxane) (PHMS) and butyl acrylate (BA) in the presence of functional comonomer N-hydroxyl-methyl acrylamide (NMA) was conducted by batch emulsion copolymerization to modify the properties of polysiloxane. Morphology of graft copolymer particles was characterized by transmission electron microscopy. The effect of polymerization method, PHMS content, initiator concentration, and NMA content on stability of emulsion, morphology, size of particle, and rheological properties were investigated. It has been found that stability of emulsion is better by semicontinuous emulsion polymerization than that of batch emulsion polymerization and it increased with increasing PHMS-NMA concentration. Increasing PHMS concentration and NMA concentration, the particle size and the viscosities increase. The property of resistance to electrolytes of graft copolymer emulsions and swelling property of film were also discussed. Results showed PHMS-g-P [butylacrylate (BA)-N-hydroxyl-methyl acrylamide (NMA)] graft copolymer emulsion has good resistance to electrolytes and the water absorption of its film increases with increasing BA-NMA content grafted onto PHMS. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 2209–2217, 1999

The lateral-line sense organs in the skin of larval, juvenile and adult salamanders (Andrias davidianus) were examined by light and scanning electron microscopy. In addition to mechanoreceptive neuromasts, there are electroreceptive ampullary organs. Anatomically, the latter are similar to the ampullary organs of some other urodeles. In the giant salamander they occur only in larvae and disappear after metamorphosis. Neuromasts are arranged in lines and in different orientations that apparently maximize directionality. © 1995 Wiley-Liss, Inc.