The Experts below are selected from a list of 258 Experts worldwide ranked by ideXlab platform
Adriana Ruggiero - One of the best experts on this subject based on the ideXlab platform.
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of Andean passerine birds: spatial patterns in Environmental Resistance and anisotropy
2016Co-Authors: Adriana Ruggiero, Rib NegroAbstract:Aim The geographical distribution of 839 Andean passerine species was analysed using two biogeographical indices: Environmental Resistance (R50) and anisotropy (A50). R50 quantifies the loss of biotic resemblance occurring from any point in the map to the rest of the continent. A50 quantifies the extent to which the perimeter: area ratio of the geographical ranges of all species whose distributions overlap at any particular location depart from the perimeter: area ratio of a circle. Three predictions derived from the climatic-tolerance hypothesis were tested: (1) the latitudinal Rapoport effect predicts an increase in the range-sizes of species, and hence a decrease in the values of R50, towards the south; (2) Janzen's argument that 'mountain passes are higher in the tropics' predicts greater anisotropy in the tropics; (3) because Environmental conditions are relatively constant across the tropics, and begin to change at the boundaries, this predicts high spatial turnover - and hence rapid change of R50 values - at the limits of the tropics.
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Size and shape of the geographical ranges of Andean passerine birds: spatial patterns in Environmental Resistance and anisotropy
Journal of Biogeography, 2002Co-Authors: Adriana RuggieroAbstract:Aim The geographical distribution of 839 Andean passerine species was analysed using two biogeographical indices: Environmental Resistance (R50) and anisotropy (A50). R50 quantifies the loss of biotic resemblance occurring from any point in the map to the rest of the continent. A50 quantifies the extent to which the perimeter : area ratio of the geographical ranges of all species whose distributions overlap at any particular location depart from the perimeter : area ratio of a circle. Three predictions derived from the climatic-tolerance hypothesis were tested: (1) the latitudinal Rapoport effect predicts an increase in the range-sizes of species, and hence a decrease in the values of R50, towards the south; (2) Janzen’s argument that ‘mountain passes are higher in the tropics’ predicts greater anisotropy in the tropics; (3) because Environmental conditions are relatively constant across the tropics, and begin to change at the boundaries, this predicts high spatial turnover – and hence rapid change of R50 values – at the limits of the tropics. Location The Andes, in South America. Methods The geographical ranges of 839 passerine species were drawn on a standardized grid map of the Andean region. The presence–absence (1–0) of each species in each of the 150 cells in the grid map was recorded. These data were used to create equiprobabilistic maps, which then were used to estimate a value of R50 and A50 for each cell in the grid map (sensuRapoport, 1975, 1979, 1982). Results The spatial patterns in R50 and A50 offer partial support to the original predictions. The tendency for R50 data to decrease with latitude (Rapoport effect) vanishes after controlling for differences in species richness among latitudes compared. In contrast, A50 data clearly offer indirect support to Janzen’s prediction of narrower climatic tolerances of species around the tropics, even after controlling for differences in species richness. The Andean passerine species confirm that spatial turnover of species exists at the southern edge of the tropics, and also at different latitudes within the tropics. Main conclusions The analysis suggests that it is the major structural change in the topography of mountains – and not merely latitude – that ultimately governs the spatial variation in size and shape of species ranges along the Andes.
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The geographic ranges of mammalian species in South America: spatial patterns in Environmental Resistance and anisotropy
Journal of Biogeography, 1998Co-Authors: Adriana Ruggiero, John H. Lawton, Tim M. BlackburnAbstract:We analyse the geographical distribution of South American mammalian species using two biogeographic indices: Environmental Resistance (R50) and anisotropy (A50). R50 quantifies the loss of biotic resemblance occurring from any point in the map to the rest of the continent. A50 quantifies the extent to which the perimeter: area ratio of the geographical ranges of all species whose distributions overlap at any particular location depart from the perimeter: area ratio of a circle. We test for the latitudinal Rapoport effect that predicts an increase in the range-sizes of mammalian species, and hence a decrease in the values of R50, towards the south. We test for the effect of mountains on species' ranges, given that Janzen's argument that 'mountain passes are higher in the tropics' implicitly predicts greater anisotropy in the tropics. Continental spatial patterns of variation in R50 and A50 suggest a biogeographic division of South America consistent with most classical zoogeographical classifications proposed for the continent. Rapid change in mammalian range-sizes and shapes occurs at the limit between the Guayano-Brazilian and Andean-Patagonean subregions. R5o data do not support the latitudinal Rapoport effect: the most widespread species locate in the eastern portions of Brazil, the most restricted ones are in association with the Andes. A50 data support Janzen's prediction: the effect of mountains on species' distributions is greater in equatorial and central regions of the Andes rather than in the south. R50-and A50-contour maps reveal that, mainly due to the effects of the lie of the land and likely differences in the history of the fauna, the continent has a biogeographic texture which must have major constraints on local ecological patterns and processes. This stresses the importance of considering the role of biogeographic structure in the analyses of geographical gradients in species' distributions.
Marie Nykvist - One of the best experts on this subject based on the ideXlab platform.
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Influenza A/H4N2 mallard infection experiments further indicate zanamivir as less prone to induce Environmental Resistance development than oseltamivir.
The Journal of general virology, 2019Co-Authors: Viktoria Tepper, Marie Nykvist, Anna Gillman, Erik Skog, Michelle Wille, Hanna Söderström Lindström, Chaojun Tang, Richard H. Lindberg, Åke Lundkvist, Josef D. JärhultAbstract:Influenza A/H4N2 Mallard infection experiments further indicate zanamivir as less prone to induce Environmental Resistance development than oseltamivir
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Prescription – Pollution – Poo – Pandemics - Priorities : Neuraminidase Inhibitors from an Environmental Resistance Development Perspective
2018Co-Authors: Marie NykvistAbstract:The natural Influenza A virus (IAV) host is waterfowl. Human IAV is treated with neuraminidase inhibitors (NAIs), which are stockpiled worldwide in case of an IAV pandemic. As the drugs escape regu ...
Tim M. Blackburn - One of the best experts on this subject based on the ideXlab platform.
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Environmental Resistance predicts the spread of alien species
Nature ecology & evolution, 2021Co-Authors: Rebecca S. L. Lovell, Tim M. Blackburn, Ellie E. Dyer, Alex L. PigotAbstract:The unabating rise in the number of species introduced outside of their native range makes predicting the spread of alien species an urgent challenge. Most predictions use models of the ecological niche of a species to identify suitable areas for invasion, but these predictions may have limited accuracy. Here, using the global alien avifauna, we demonstrate an alternative approach for predicting alien spread based on the Environmental Resistance of the landscape. This approach does not require any information on the ecological niche of the invading species and, instead, uses gradients of biotic similarity among native communities in the invaded region to predict the most likely routes of spread. We show that Environmental Resistance predicts patterns of spread better than a null model of random dispersal or a model based on climate matching to the native range of each species. Applying this approach to simulate future spread reveals major regional differences in projected invasion risk, shaped by proximity to existing invasion hotspots as well as gradients in Environmental Resistance. Our results show how Environmental Resistance may provide a general and complementary approach for predicting invasion risk that can be rapidly deployed even when information on the niche or the identity of potential invaders is unknown. The authors show how a Resistance index based on biotic assemblage resemblance can predict the spread of invasive bird species without having to estimate their ecological niche.
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The geographic ranges of mammalian species in South America: spatial patterns in Environmental Resistance and anisotropy
Journal of Biogeography, 1998Co-Authors: Adriana Ruggiero, John H. Lawton, Tim M. BlackburnAbstract:We analyse the geographical distribution of South American mammalian species using two biogeographic indices: Environmental Resistance (R50) and anisotropy (A50). R50 quantifies the loss of biotic resemblance occurring from any point in the map to the rest of the continent. A50 quantifies the extent to which the perimeter: area ratio of the geographical ranges of all species whose distributions overlap at any particular location depart from the perimeter: area ratio of a circle. We test for the latitudinal Rapoport effect that predicts an increase in the range-sizes of mammalian species, and hence a decrease in the values of R50, towards the south. We test for the effect of mountains on species' ranges, given that Janzen's argument that 'mountain passes are higher in the tropics' implicitly predicts greater anisotropy in the tropics. Continental spatial patterns of variation in R50 and A50 suggest a biogeographic division of South America consistent with most classical zoogeographical classifications proposed for the continent. Rapid change in mammalian range-sizes and shapes occurs at the limit between the Guayano-Brazilian and Andean-Patagonean subregions. R5o data do not support the latitudinal Rapoport effect: the most widespread species locate in the eastern portions of Brazil, the most restricted ones are in association with the Andes. A50 data support Janzen's prediction: the effect of mountains on species' distributions is greater in equatorial and central regions of the Andes rather than in the south. R50-and A50-contour maps reveal that, mainly due to the effects of the lie of the land and likely differences in the history of the fauna, the continent has a biogeographic texture which must have major constraints on local ecological patterns and processes. This stresses the importance of considering the role of biogeographic structure in the analyses of geographical gradients in species' distributions.
Josef D. Järhult - One of the best experts on this subject based on the ideXlab platform.
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Influenza A/H4N2 mallard infection experiments further indicate zanamivir as less prone to induce Environmental Resistance development than oseltamivir.
The Journal of general virology, 2019Co-Authors: Viktoria Tepper, Marie Nykvist, Anna Gillman, Erik Skog, Michelle Wille, Hanna Söderström Lindström, Chaojun Tang, Richard H. Lindberg, Åke Lundkvist, Josef D. JärhultAbstract:Influenza A/H4N2 Mallard infection experiments further indicate zanamivir as less prone to induce Environmental Resistance development than oseltamivir
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Environmental Resistance development to influenza antivirals: a case exemplifying the need for a multidisciplinary One Health approach including physicians
Acta Veterinaria Scandinavica, 2018Co-Authors: Josef D. JärhultAbstract:A multidisciplinary approach is a prerequisite for One Health. Physicians are important players in the One Health team, yet they are often hard to convince of the benefits of the One Health approach. Here, the case for multidisciplinarity including physicians is made using the example of Environmental Resistance development to influenza antivirals. Neuraminidase inhibitors are the major class of anti-influenza pharmaceuticals, and extensively stockpiled globally as a cornerstone of pandemic preparedness, especially important in the first phase before vaccines can be mass-produced. The active metabolite of oseltamivir that is excreted from treated patients degrades poorly in conventional sewage treatment processes and has been found in river waters. Dabbling ducks constitute the natural influenza A virus reservoir and often reside near sewage treatment plant outlets, where they may be exposed to neuraminidase inhibitor residues. In vivo experiments using influenza-infected Mallards exposed to neuraminidase inhibitors present in their water have shown Resistance development and persistence, demonstrating that Resistance may be induced and become established in the influenza strains circulating in natural hosts. Neuraminidase inhibitor Resistance genes may become part of a human-adapted influenza virus with pandemic potential through reassortment or direct transmission. A pandemic caused by a neuraminidase inhibitor-resistant influenza virus is a serious threat as the first line defense in pandemic preparedness would be disarmed. To assess the risk for Environmental influenza Resistance development, a broad multidisciplinary team containing chemists, social scientists, veterinarians, biologists, ecologists, virologists, epidemiologists, and physicians is needed. Information about One Health early in high school and undergraduate training, an active participation of One Health-engaged physicians in the debate, and more One Health-adapted funding and publication possibilities are suggested to increase the possibility to engage physicians.
John Lopez - One of the best experts on this subject based on the ideXlab platform.
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Microhardness testing of plastics: Literature review
Polymer Testing, 1993Co-Authors: John LopezAbstract:Abstract A review is presented of microhardness tests applicable to plastics. The methods are outlined and the effect of test variables considered. Published literature describing applications of microhardness measurements to plastics including structure and Environmental Resistance are reviewed.