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Distinct Preferences (distinct + preference)
Selected AbstractsCan C4 plants contribute to aquatic food webs of subtropical streams?FRESHWATER BIOLOGY, Issue 6 2003Joanne E. Clapcott Summary 1. Recent stable isotope studies have revealed that C4 plants play a minor role in aquatic food webs, despite their often widespread distribution and production. We compared the breakdown of C3 (Eucalyptus) and C4 (Saccharum and Urochloa) plant litter in a small rain forest stream and used laboratory feeding experiments to determine their potential contribution to the aquatic food web. 2. All species of litter broke down at a fast rate in the stream, although Urochloa was significantly faster than Eucalyptus and Saccharum. This was consistent with the observed higher total organic nitrogen of Urochloa compared with the other two species. 3. The breakdown of Urochloa and Saccharum was, however, not associated with shredding invertebrates, which were poorly represented in leaf packs compared with the native Eucalyptus. The composition of the invertebrate fauna in packs of Urochloa quickly diverged from that of the other two species. 4. Feeding experiments using a common shredding aquatic insect Anisocentropus kirramus showed a distinct preference for Eucalyptus over both C4 species. Anisocentropus was observed to ingest C4 plant litter, particularly in the absence of other choices, and faecal material collected was clearly of C4 origin, as determined by stable isotope analysis. However, the stable carbon isotope values of the larvae did not shift away from their C3 signature in any of the feeding trials. 5. These data suggest that shredders avoid the consumption of C4 plants, in favour of native C3 species that appear to be of lower food quality (based on C : N ratios). Lower rates of consumption and lack of assimilation of C4 carbon also suggest that shredders may have a limited ability to process this material, even in the absence of alternative litter sources. Large scale clearing of forest and vegetation for C4 crops such as sugarcane will undoubtedly have important consequences for stream ecosystem function. [source] The therapeutic profile of zolmitriptan in clinical practiceINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 8 2004H.C. Diener Summary The efficacy and tolerability of the 5-HT1B/1D -receptor agonist zolmitriptan was evaluated in an open post-marketing surveillance study in 12,919 patients, treating 36,510 migraine attacks. Mean visual analogue scale scores for pain decreased (6.9,2.2; 68% improvement) and scores for impairment of normal activities decreased (6.6,2.2; 67% improvement) at 2 h after dose. Non-headache symptoms of migraine resolved in 73,86% of attacks. Improvement was achieved within 2 h in >80% of attacks and within 1 h in 37% of attacks. This high level of efficacy was achieved with a single 2.5 mg dose in 95% of attacks. Compared with previous migraine treatments, 85% of patients preferred zolmitriptan for efficacy and 56% for better tolerability. Corresponding preference rates were 87 and 63% when compared with ergot alkaloids. Adverse events occurred in 2% of patients and were either typical class effects or known symptoms and complications of migraine. These results provide evidence for the high efficacy and good tolerability of the 2.5 mg dose of zolmitriptan in clinical practice in migraine. Zolmitriptan was very well tolerated, with patients expressing a distinct preference for zolmitriptan over previous treatments. [source] Ground beetle species (Coleoptera, Carabidae) associations with land cover variables in northern England and southern ScotlandECOGRAPHY, Issue 4 2004M. D. Eyre Distribution data concerning 172 ground beetle species derived from 1145 pitfall trap sites in northern England and southern Scotland were used to assess the relationship between species distribution and 12 satellite-derived land cover variables at the regional scale. A number of species were strongly associated with one cover type and negatively with others. The major variation was for preferences for covers in upland or lowland parts of the region. Other distinct preferences for some species were covers such as those at the coast whilst a number of common species showed no strong preference for any cover variable. The synthesis of ground beetle species distribution and satellite-derived cover data is discussed in relation to environmental assessment and change. [source] Winners and losers of conservation policies for European eel, Anguilla anguilla: an economic welfare analysis for differently specialised eel anglersFISHERIES MANAGEMENT & ECOLOGY, Issue 2 2010M. DOROW Abstract, Recreational specialisation theory was coupled with a discrete choice experiment to understand eel, Anguilla anguilla L., angler's heterogeneity in their reaction to regulatory changes and the associated welfare changes. Differently specialised eel anglers exhibited distinct preferences for catch variables and eel angling regulations. All anglers preferred slightly to moderately stricter regulations than are currently in place; however, such policies particularly benefited casual eel anglers. In contrast, advanced eel anglers would be most penalised by highly restrictive regulations as indicated by substantial reductions in economic welfare. Aversions to stricter regulations found for advanced anglers contradicted predictions from specialisation theory. From an eel management perspective, the implementation of some simple tools such as increased minimum-size limits will reduce angling mortality on eel and simultaneously increase the welfare of anglers. By contrast, highly restrictive eel angling regulations will result in considerable economic welfare losses of several million , per year for northern Germany alone. [source] Foetal and adult cardiomyocyte progenitor cells have different developmental potentialJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 4 2010Patrick Van Vliet Abstract In the past years, cardiovascular progenitor cells have been isolated from the human heart and characterized. Up to date, no studies have been reported in which the developmental potential of foetal and adult cardiovascular progenitors was tested simultaneously. However, intrinsic differences will likely affect interpretations regarding progenitor cell potential and application for regenerative medicine. Here we report a direct comparison between human foetal and adult heart-derived cardiomyocyte progenitor cells (CMPCs). We show that foetal and adult CMPCs have distinct preferences to differentiate into mesodermal lineages. Under pro-angiogenic conditions, foetal CMPCs form more endothelial but less smooth muscle cells than adult CMPCs. Foetal CMPCs can also develop towards adipocytes, whereas neither foetal nor adult CMPCs show significant osteogenic differentiation. Interestingly, although both cell types differentiate into heart muscle cells, adult CMPCs give rise to electrophysiologically more mature cardiomyocytes than foetal CMPCs. Taken together, foetal CMPCs are suitable for molecular cell biology and developmental studies. The potential of adult CMPCs to form mature cardiomyocytes and smooth muscle cells may be essential for cardiac repair after transplantation into the injured heart. [source] Product innovation charters: Mission statements for new productsR & D MANAGEMENT, Issue 1 2002Christopher K. Bart This article presents findings from an exploratory study into the content and impact of product innovation charters (PICs) in 86 North American corporations. The findings demonstrate that managers have some distinct preferences in terms of the items that they choose to include in a PIC and that certain components seem to be more important to mention than others. The findings also make evident the relationship that PICs have with selected performance measures. The results suggest that product innovation charters, like their mission statement ,cousins', may be of more value than most managers realize. [source] | |||||||||||||