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11.
Journal of Plant Diseases and Protection - Prior to the first occurrence of chestnut blight in 1976, leaf spot caused by Cylindrosporium castaneae was one of the most important diseases of European... 相似文献
12.
Lucy M.I. Webster Paul C.D. Johnson Aileen Adam Barbara K. MableLukas F. Keller 《Veterinary parasitology》2008
Benzimidazole (BZ) resistance is widespread in nematode parasites of livestock, but very little is known about the levels of BZ resistance in parasites with avian hosts. We investigated BZ resistance in Trichostrongylus tenuis, a nematode parasite of red grouse, Lagopus lagopus scotica. BZ anthelmintics had been in use in this system for up to 15 years, yet existing phenotypic evidence for resistance was inconclusive. We screened 1530 individuals from 14 populations at the principal β-tubulin locus for BZ resistance (isotype 1, residue 200) and 940 of these at two further resistance sites (isotype 1, residue 167; isotype 2, residue 200). No BZ resistant genotypes were found. Alternative mechanisms may be responsible for BZ resistance in this system, or the method and timing of treatments may reduce selection pressure for BZ resistance by creating substantial refugia for susceptible genotypes. 相似文献
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Nikki Baggaley Allan Lilly Kirsty Blackstock Karen Dobbie Adam Carson Fraser Leith 《Soil Use and Management》2020,36(1):19-26
Surface runoff, erosion, compaction and the leaching of potential pollutants from land can degrade the soil resource and damage the water environment, reducing crop yields, causing loss of valuable nutrients and organic matter, together with increasing flood risk. Increasingly, it is recognized that scientific information must be translated into practical tools to change practices and protect the soil and water resource. Working alongside agencies in Scotland, we applied a suite of simple, transparent, rule-based models to identify areas most at risk of exporting sediment and pollutants that may degrade water quality based on field-scale (1:25,000) soil maps. The maps have been used by Scottish Environment Protection Agency, Scottish Water and Scottish Government to assess soil risks to waters from field to regional scale. The work brought scientists together with policy makers, agencies and the water industry to pool their knowledge to apply these practical tools for decision-making. It highlights the need to apply existing knowledge to answer salient questions. All three examples described show that providing the right type of information, which is based on fundamental soils data, can directly influence the implementation of policies, investment and monitoring decisions and provide evidence in support of government. However, this requires both researchers and agency scientists to develop skills as knowledge brokers and to normalize the use of soil data in everyday agency settings. 相似文献
15.
Matts Lindbladh Adam Felton Renats Trubins Ola Sallnäs 《European Journal of Forest Research》2011,130(5):861-869
As resources allocated specifically for conservation are limited, there is a need to ensure conservation policy initiatives
lead to effective conservation outcomes. In this study, we investigated the potential conservation benefits from alternative
spatial allocations of old deciduous stands to a landscape dominated by coniferous production forests owned primarily by non-industrial
private forest owners. As a target species, we used the long-tailed tit (Aegithalos caudatus), a species associated with deciduous forests and known to be sensitive to isolation. We used a previously published model
based on empirical data on the occurrence of this species, to assess the probability of occurrence of the bird in a 4,000 km2 area in southern Sweden for which we possess detailed spatial GIS data (kNN data) of tree species composition and age. We
assessed alternative scenarios where old deciduous forest was allocated with or without respect to distance from existing
old deciduous forests. Due to the long-tailed tit’s habitat requirement increasing the amount of old deciduous forests close
to existing habitats was the most effective strategy. However, the potential advantages of this strategy may in fact be overturned
in favor of the other scenarios if ownership structures and probable uptake rates of policy initiatives are also considered.
If a policy initiative is targeted toward owners with properties in close proximity to existing suitable habitat, when compared
to if all forest owners are targeted, a higher proportion of owners is needed to participate in order to achieve the same
degree of habitat creation for the species. Here, we discuss the potential benefits for effective conservation policy formulation
from integrating spatially explicit datasets and detailed ecological knowledge with land-ownership structures and policy uptake
scenarios. 相似文献
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Hume AJ Finkel JS Kamil JP Coen DM Culbertson MR Kalejta RF 《Science (New York, N.Y.)》2008,320(5877):797-799
As obligate intracellular parasites, viruses expertly modify cellular processes to facilitate their replication and spread, often by encoding genes that mimic the functions of cellular proteins while lacking regulatory features that modify their activity. We show that the human cytomegalovirus UL97 protein has activities similar to cellular cyclin-cyclin-dependent kinase (CDK) complexes. UL97 phosphorylated and inactivated the retinoblastoma tumor suppressor, stimulated cell cycle progression in mammalian cells, and rescued proliferation of Saccharomyces cerevisiae lacking CDK activity. UL97 is not inhibited by the CDK inhibitor p21 and lacks amino acid residues conserved in the CDKs that permit the attenuation of kinase activity. Thus, UL97 represents a functional ortholog of cellular CDKs that is immune from normal CDK control mechanisms. 相似文献
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Grova N Feidt C Crépineau C Laurent C Lafargue PE Hachimi A Rychen G 《Journal of agricultural and food chemistry》2002,50(16):4640-4642
Polycyclic aromatic hydrocarbons (PAHs), mainly formed by incomplete anthropogenic organic matter combustion, are ubiquitous in the environment. To assess milk PAH contamination sources, milk samples were collected from the tank milk at farms located near potential contaminating emission sources such as cementworks, steelworks, and motorways. PAH analyses were carried out by gas chromatography coupled to mass spectrometry. Eight PAHs were identified in milk: naphthalene, acenaphthylene, acenaphthene, fluorene, anthracene, fluoranthene, pyrene, and benzo[a]anthracene. For all potential contaminating sources, these eight PAHs were detected with similar profiles and at low concentrations except for fluorene and naphthalene, for which source-molecule interaction is pointed out. 相似文献
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