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A bismuth-organic compound containing 2,2':6'2"-terpyridine (terpy) and 2-thiophenecarboxylate (TC), of the general formula (terpy)Bi(κ2 -TC)3 ⋅0.47 H2 O (BiOM-1), has been synthesized under hydrothermal conditions. Addition of a lanthanide nitrate solution to the reaction mixture led to statistical replacement of the bismuth centers, and yielded isomorphous lanthanide containing compounds Bi1-x Lnx OM-1 (Ln=Nd, Sm, Eu, Tb, Dy, Er, and Yb) that showed bismuth and/or ligand sensitized lanthanide-centered emission, and the first example of NIR emission from a lanthanide doped BiOM. The structure was determined by single-crystal X-ray diffraction, and the level and uniformity of lanthanide ion incorporation into the bismuth host was determined by ICP-OES and electron microprobe analysis. For the visible emitters, lifetime data and quantum yields are presented. A high efficiency of sensitization was calculated for the europium analog (50.1 %), showing significant improvement over previously reported europium thiophenecarboxylates. These novel materials may provide strategies to address concerns over the long-term sustainability of the rare earth elements, especially relating to optical devices.

At time of writing Kenya holds c. 84% of the remaining in situ population of Critically Endangered Eastern black rhinoceros Diceros bicornis michaeli. The Kenyan 5 year Black Rhino Conservation and Management Strategy has given highest priority to the biological management of the subspecies in order to help achieve and maintain rapid metapopulation growth to increase rhinoceros numbers. Specific training and capacity building in monitoring of rhinoceros, from collection of field data to status reporting, have been implemented. Procedures to assess ecological carrying capacity for Eastern black rhinoceros habitat have been developed to help establish new viable populations and to optimize the management of existing sanctuaries, some of which face loss of suitable habitat owing to competition for resources between rhinoceros and other browsers. The management objective is to maintain rhinoceros populations below the ecological carrying capacity of a reserve in order to increase reproduction in‘donor'populations as well as the trans-location of animals to create new populations with the potential for rapid growth. The conservation value of establishing site-level support relationships is also discussed. Kenya, for the first time since the 1970s, achieved a growth rate of >5% over the period 2004 and 2005 (the national goal is to increase numbers by at least 5%).