13 research outputs found

    Background matching in the brown shrimp Crangon crangon : adaptive camouflage and behavioural-plasticity

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    A combination of burrowing behaviour and very efficient background matching makes the brown shrimp Crangon crangon almost invisible to potential predators and preys. This raises questions on how shrimp succeed in concealing themselves in the heterogeneous and dynamic estuarine habitats they inhabit and what type of environmental variables and behavioural factors affect their colour change abilities. Using a series of behavioural experiments, we show that the brown shrimp is capable of repeated fast colour adaptations (20% change in dark pigment cover within one hour) and that its background matching ability is mainly influenced by illumination and sediment colour. Novel insights are provided on the occurrence of non-adaptive (possibly stress) responses to background changes after long-time exposure to a constant background colour or during unfavourable conditions for burying. Shrimp showed high levels of intra- and inter-individual variation, demonstrating a complex balance between behavioural-plasticity and environmental adaptation. As such, the study of crustacean colour changes represents a valuable opportunity to investigate colour adaptations in dynamic habitats and can help us to identify the mayor environmental and behavioural factors influencing the evolution of animal background matching

    Cyclosporin for severe ulcerative colitis does not increase the rate of perioperative complications.

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    PURPOSE: Cyclosporin is used in severe ulcerative colitis that is refractory to intravenous steroids. Cyclosporin is a potent immunosuppressant and can cause side effects such as opportunistic infections. This study aimed to investigate the incidence of perioperative complications in patients treated with intravenous cyclosporin and steroids compared with patients treated with intravenous steroids alone. METHODS: We retrospectively reviewed the case notes of 44 patients with severe ulcerative colitis who underwent total abdominal colectomy and ileostomy. Twenty-five patients were treated with intravenous steroids and 19 patients were treated with intravenous cyclosporin and steroids. Details were recorded with respect to age, length of illness, extent of disease, Truelove and Witt's criteria, hemoglobin and albumin at surgery, surgical procedure, and perioperative morbidity. RESULTS: Twenty-four percent of patients treated with intravenous steroids alone and 15.8 percent of patients treated with intravenous cyclosporin and steroids had major surgical complications. Sixteen percent of patients treated with intravenous steroids alone and 5.2 percent of patients treated with intravenous cyclosporin and steroids had minor surgical complications. Eight percent of patients treated with intravenous steroids alone and 10.5 percent of patients treated with intravenous cyclosporin and steroids had major medical complications. There was no mortality in either group. CONCLUSIONS: There is no increased incidence of perioperative complications associated with the use of intravenous cyclosporin in addition to steroids in acute severe ulcerative colitis provided cyclosporin treatment is for a defined period and surgery is not delayed

    Free interpolation in Bergman spaces

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    Interpolation of bounded sequences

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    Contextualising education in Pakistan, a white paper: Global/national articulations in education policy

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    This article contextualises Education in Pakistan, a White Paper (2007), an influential education policy paper in Pakistan. The focus is on the ways the White Paper constructs its own contexts as a complement to the policy solutions proffered. Here we recognise Seddon's point about the discursive work of policy in constructing context. We focus on the way the White Paper constructs its political/ideological context and its global/national context. The White Paper works with the trope of a binary construction of Islam - fundamentalist or moderate - which rearticulates Orientalist Western constructions. The analysis of the construction of the global/national contexts demonstrates the framing of the policy by the Millennium Development Goals, and the Washington and postWashington consensus
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