A highly sensitive fluorescent probe 1 for selective detection of Hg ion in mixed N,N-dimethylformamide aqueous media was designed and prepared by incorporating the well-known Rhodamine 6G fluorophore and a carbohydrazone binding unit into one molecule. The fluorescent probe 1 can detect the parts per billion level of HgII in a mixed aqueous environment and displays a highly selective response of fluorescence enhancement toward HgII.

The feather is a complex epidermal organ with hierarchical branches and represents a multi-layered topological transformation of keratinocyte sheets. Feathers are made in feather follicles. The basics of feather morphogenesis were previously described (Lucas and Stettenheim, 1972). Here we review new molecular and cellular data. After feather buds form (Jiang et al., 2004), they invaginate into the dermis to form feather follicles. Above the dermal papilla is the proliferating epidermal collar. Distal to it is the ramogenic zone where the epidermal cylinder starts to differentiate into barb ridges or rachidial ridge. These neoptile feathers tend to be downy and radially symmetrical. They are replaced by teleoptile feathers which tend to be bilateral symmetrical and more diverse in shapes. We have recently developed a "transgenic feather" protocol that allows molecular analyses: BMPs enhance the size of the rachis, Noggin increases branching, while anti-SHH causes webbed branches. Different feather types formed during evolution (Wu et al., 2004). Pigment patterns along the body axis or intra-feather add more colorful distinctions. These patterns help facilitate the analysis of melanocyte behavior. Feather follicles have to be connected with muscles and nerve fibers, so they can be integrated into the physiology of the whole organism. Feathers, similarly to hairs, have the extraordinary ability to go through molting cycles and regenerate. Some work has been done and feather follicles might serve as a model for stem cell research. Feather phenotypes can be modulated by sex hormones and can help elucidate mechanisms of sex hormone-dependent growth control. Thus, the developmental biology of feather follicles provides a multi-dimension research paradigm that links molecular activities and cellular behaviors to functional morphology at the organismal level.

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Three lanthanide-thiophenedicarboxylate hybrid compounds, [(Eu2(TDC)3(CH3OH)2·(CH3OH)] (1), [(Yb2(TDC)3(DMF)(H2O)·(CH3CH2OH)] (2), and [(Tb2(TDC)3(H2O)4] (3) (where TDC is deprotonated thiophene-2,5-dicarboxylic acid and DMF is dimethylformamide), have been prepared by a hydrothermal method. The TDC ligands exhibit two unprecedented (κ2-κ1-μ2)−(κ1-κ1)−μ5 and (κ2)−(κ2)−μ2 coordination modes as well as other various modes. Structure analysis reveals that 2,5-thiophenedicarboxylic acid play a versatile role toward different lanthanide ions to form three-dimensional inorganic−organic hybrid frameworks. The luminescence experiments show that Eu(III) and Tb(III) compounds exhibit typical luminescence in the visible region, while the Yb(III) compound emits characteristic near-infrared luminescence in the solid state even with the coordinated water molecules. Besides luminescence, the Tb(III) compound also shows weak ferromagnetic behavior, which indicates that it is acting as a dual function material.