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81.
The Llyn Padarn wreck is a bateau style vessel of the late 18th century. Assuming that it is one of the boats built by the quarry company it was constructed between February 1788 and February 1789. If it was built by one of the independent boatmen its date of construction is uncertain, however its excellent state of preservation suggests that it was still relatively new when it sank, and this also would point towards it being one of the company boats. Whatever the date of building, the boat certainly sank between 1788 and 1824, but the quality of the cargo suggests that it was towards the beginning rather than the end of that period. It is of historic interest as one of the few surviving examples of the bateau style of boat building. and it is also one of the best preserved examples of its kind. It also throws some light on the early history of the North Wales slate industry, on the history of travel and transport on Llyn Padarn, and on the lake settlements at Cwm y Glo and Penllyn. The Padarn boat is now being put into E'EG conservation by the National Museum of Wales, and will subsequently be exhibited in the North Wales Quarry Museum at Llanberis. It would be interesting to know what happened to all the other boats which were evidently working on the lakes in the 18th and early 19th centuries. No doubt most were destroyed when their usefulness came to an end, but if one sank there may well be others, and in due course the Welsh Institute of Maritime Archaeology hopes to carry out a remote sensing survey of Padarn using side-scan sonar and low light television. In addition, the upper lake, Llyn Peris, is to be drained in connection with the massive Pump Storate Generating Scheme which has once again turned the derelict quarries into one of the largest civil engineering projects in Europe. It is certain that these two lakes still have secrets to reveal. I would like to thank the staff of the North Wales Quarry Museum for their patient assistance and advice in the preparation of this article; Mr Brian Buckle of North Wales Divers Ltd, Colwyn Bay, for providing me with a copy of his survey of the wreck site; Mr Derwyn Jones, the Welsh Librarian in the University Library, Bangor for bringing to my attention various references to Margaret ferch Evans, and my colleague Mr Emlyn Sherrington for translating certain passages from the Welsh.  相似文献   
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A total of 1164 temporal bones from various cemetery sites in England were examined using a fibre optic endoscope. Eight bones were found to have evidence of otosclerosis in which proliferative new bone fixes the footplate of the stapes into the oval window, causing deafness. A prevalence of 0.9 per cent in this study is comparable with the incidence found in modern white populations and with that found in a study of 2760 Lithuanian temporal bones of various periods.  相似文献   
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Infective lesions of bone in leprosy are of two types. In the rhinomaxillary syndrome, superficial infective changes in the bones of the maxilla are due to the presence of Mycobacterium leprae. Lytic foci in the medulla or the outer cortical surface may be due to Mycobacterium leprae at the site as granulomatous lesions. The most frequent infective bone changes in leprosy are, however, sequelae of regional anaesthesia and soft tissue ulceration. The bone lesions are due to pyogenic bacteria and the nature of these infective lesions is similar to that in non-leprous conditions. The pyogenic lesions in leprosy are restricted to the bones of the hands, feet and lower legs.  相似文献   
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This paper explores potential barriers to growth in key areas which can become increasingly problematic for some smaller to medium-sized firms (SMEs) as they grow and evolve from their early status as small scale spin-offs. These potential growth barriers can occur in: finance, competition from new firms or products and organizational integration of resources. Firms that fail to properly plan, manage and allocate resources will encounter difficulties in each area. Such firms are said to have poor 'governance systems'. While not proposing a universal theory about small firm behaviour, we argue that firms can encounter the same problems associated with poor communication, bureaucracy and loss of entrepreneurial spirit that plague large firms. We also show that the routines used to promote growth based on collaboration can sometimes create problems for firms as they ignore new challenges. We elaborate various theories on the limits to growth by examining the case of IV, a university spin-off.  相似文献   
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