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Background  

Patients with Opitz GBBB syndrome present with a variable array of developmental defects including craniofacial, cardiac, and genital anomalies. Mutations in the X-linked MID1 gene, which encodes a microtubule-binding protein, have been found in ~50% of Opitz GBBB syndrome patients consistent with the genetically heterogeneous nature of the disorder. A protein highly related to MID1, called MID2, has also been described that similarly associates with microtubules.  相似文献   
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European eels, Anguilla anguilla, L., are captured in coghill nets at three commercial weirs on the Irish River Shannon during their autumn/winter seaward migration. The variations in daily silver eel catches were analysed in relation to environmental conditions, especially hydrometric and meteorological factors. Three multivariate environmental axes were distinguished with which daily eel catches could be correlated. The relative importance of various hydrometric, meteorological and temporal (seasonality, lunar phase) factors was identified, showing how hydrological and meteorological factors generally obscure the underlying lunar periodicity of the silver eel migrations at Killaloe.  相似文献   
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Ex situ (‘off-site’) management refers to keeping species in artificial conditions away from their natural habitat and includes captive breeding facilities, botanical gardens and seed banks. There is scope for ex situ programmes to be more commonly used for supplementing or establishing wild populations. However, undertaking ex situ management comes with risks, costs and uncertainties, which must be assessed in the context of available in situ (‘on-site’) management options. The PACES (Planning and Assessment for Conservation through Ex situ management) tool tailors the principles of structured decision-making to the specific problem of assessing and comparing ex situ and in situ management options. We applied the PACES tool to the mahogany glider (Petaurus gracilis), a threatened arboreal marsupial endemic to north Queensland, Australia. Through an expert elicitation process, we predicted the likely benefits of an ex situ and two in situ management options, as compared to a baseline ‘do-nothing’ scenario. The ‘in situ plus’ alternative (where extra resources are dedicated to in situ management) was predicted to result in the largest population increase according to the participants' best estimates. However, this benefit came at a much larger cost than the ex situ alternative, and without the benefit of an ex situ insurance population. The PACES tool assessment allowed the Mahogany Glider Recovery Team to document and plan the financial costs, risks and benefits of potential future management options for the mahogany glider, laying a transparent basis for future assessment and decision-making.  相似文献   
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