2 resultados para Southern Spectrophotometric Standards

em Greenwich Academic Literature Archive - UK


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Spatio-temporal data on cytotaxonomic identifications of larvae of different members of the Simulium damnosum complex collected from rivers in southern Ghana and south-western Togo from 1975 until 1997 were analysed. When the data were combined, the percentages of savannah blackflies (S. damnosum sensu stricto and S. sirbanum) in the samples were shown to have been progressively increasing since 1975. The increases were statistically significant (P < 0·001), but the rates of increase were not linear. Further analyses were conducted according to the collection seasons and locations of the samples, to account for possible biases such as savannah flies occurring further south in the dry season or a preponderance of later samples from northern rivers having more savannah flies. These analyses showed that the increasing trend was statistically significant (P< 0·0001) only during the periods April to June and October to December. The presence of adult savannah flies carrying infective larvae (L3) indistinguishable from those of Onchocerca volvulus in the study zone was confirmed by examinations of captured flies. The percentages of savannah flies amongst the human-biting populations and the percentages with L3s in the head were higher during dry seasons than wet seasons and the savannah species were found furthest south (5 °25′N) in the dry season. Comparisons of satellite images taken in 1973 and 1990 over a study area in south-western Ghana encompassing stretches of the Tano and Bia rivers demonstrated that there have been substantial increases in urban and savannah areas, at the expense of forest. This was so not only for the whole images but also for subsamples of the images taken at 1, 2, 4, 8 and 16 km distant from sites alongside the River Tano. At every distance from the river, the percentages of pixels classified as urban or savannah have increased in 1990 compared with 1973, while those classified as degraded or dense forest have decreased. The possibility that the proportionate increases in savannah forms of the vectors of onchocerciasis, and hence in the likelihood of the transmission of savannah strains of the disease in formerly forested areas, were related to the decreases in forest cover is discussed.

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Leadership and Management Standards in the UK Lifelong Learning Sector. Presentation on research findings on leadership and management in the LLS sector, in the context of UK government policy changes introducing the 2007 Principals' Qualifying Programme (PQP) delivered by the Centre for Excellence in Leadership (CEL)/Learning and Skills Improvement Service (LSIS). Discusses the role of standards in leadership and management professional practice and development and sums up the history of development of standards in relation to the National Occupational Standards (NOS) for Leadership and Management, based on the UK Management Standards Centre (MSC) Institute for Leadership and Management Standards. Discusses the Lifelong Learning UK (LLUK) Benchmark Role Specification for Principals in FE, Sixth Form and Specialist Colleges and the fact that the LSIS PQP has adopted those as part of its programme for Principal development. In the context of the implementation of standards for leadership and management, discusses the importance of values-based and research-informed leadership and the development of trust in lifelong learning sector institutions, given the multiple challenges facing vocational education and training (VET) institutions and the relative lack of recognition and support for the difficult roles taken on by Principals and senior leaders.