96 research outputs found
Commercial air transport hazard warning and avoidance system. Volume 2 - Requirements studies Final report
Operational requirements and cost effectiveness of commercial air transport hazard warning and avoidance syste
The insecticide Safari 20SG inhibits the growth of Neodothiora populina, an emerging fungal pathogen in trembling aspen
Testing at which concentration the insecticide Safari 20SG insecticide inhibits the growth fungal pathogen Neodothiora populina
Changing practices: The specialised domestic violence court process
Specialised domestic violence courts, initially developed in the United States of America, have been recognised by other jurisdictions including Canada, Australia and the United Kingdom. This article presents a case study of K Court in Toronto, drawing upon documentary evidence, direct observations and interviews with key informants. It is argued that the specialised domestic violence court process includes changing practices of some of the key stakeholders. Learning lessons from abroad can offer jurisdictions insights that can steer implementation of appropriate practices in the field
Phylogenetically Structured Differences in rRNA Gene Sequence Variation among Species of Arbuscular Mycorrhizal Fungi and Their Implications for Sequence Clustering
Arbuscular mycorrhizal (AM) fungi form mutualisms with plant roots that increase plant growth and shape plant communities. Each AM fungal cell contains a large amount of genetic diversity, but it is unclear if this diversity varies across evolutionary lineages. We found that sequence variation in the nuclear large-subunit (LSU) rRNA gene from 29 isolates representing 21 AM fungal species generally assorted into genus- and species-level clades, with the exception of species of the genera Claroideoglomus and Entrophospora. However, there were significant differences in the levels of sequence variation across the phylogeny and between genera, indicating that it is an evolutionarily constrained trait in AM fungi. These consistent patterns of sequence variation across both phylogenetic and taxonomic groups pose challenges to interpreting operational taxonomic units (OTUs) as approximations of species-level groups of AM fungi. We demonstrate that the OTUs produced by five sequence clustering methods using 97% or equivalent sequence similarity thresholds failed to match the expected species of AM fungi, although OTUs from AbundantOTU, CD-HIT-OTU, and CROP corresponded better to species than did OTUs from mothur or UPARSE. This lack of OTU-to-species correspondence resulted both from sequences of one species being split into multiple OTUs and from sequences of multiple species being lumped into the same OTU. The OTU richness therefore will not reliably correspond to the AM fungal species richness in environmental samples. Conservatively, this error can overestimate species richness by 4-fold or underestimate richness by one-half, and the direction of this error will depend on the genera represented in the sample.
IMPORTANCE Arbuscular mycorrhizal (AM) fungi form important mutualisms with the roots of most plant species. Individual AM fungi are genetically diverse, but it is unclear whether the level of this diversity differs among evolutionary lineages. We found that the amount of sequence variation in an rRNA gene that is commonly used to identify AM fungal species varied significantly between evolutionary groups that correspond to different genera, with the exception of two genera that are genetically indistinguishable from each other. When we clustered groups of similar sequences into operational taxonomic units (OTUs) using five different clustering methods, these patterns of sequence variation caused the number of OTUs to either over- or underestimate the actual number of AM fungal species, depending on the genus. Our results indicate that OTU-based inferences about AM fungal species composition from environmental sequences can be improved if they take these taxonomically structured patterns of sequence variation into account
Atomically Resolved Imaging of Highly Ordered Alternating Fluorinated Graphene
One of the most desirable goals of graphene research is to produce ordered 2D
chemical derivatives of suitable quality for monolayer device fabrication. Here
we reveal, by focal series exit wave reconstruction, that C2F chair is a stable
graphene derivative and demonstrates pristine long-range order limited only by
the size of a functionalized domain. Focal series of images of graphene and C2F
chair formed by reaction with XeF2 were obtained at 80 kV in an
aberration-corrected transmission electron microscope. EWR images reveal that
single carbon atoms and carbon-fluorine pairs in C2F chair alternate strictly
over domain sizes of at least 150 nm^2 with electron diffraction indicating
ordered domains >/= 0.16 square micrometer. Our results also indicate that,
within an ordered domain, functionalization occurs on one side only as theory
predicts. Additionally we show that electron diffraction provides a quick and
easy method for distinguishing between graphene, C2F chair and fully
fluorinated stoichiometric CF 2D phases
Graphene re-knits its holes
Nano-holes, etched under an electron beam at room temperature in singlelayer
graphene sheets as a result of their interaction with metalimpurities, are
shown to heal spontaneously by filling up with either non-hexagon,
graphene-like, or perfect hexagon 2D structures. Scanning transmission electron
microscopy was employed to capture the healing process and study atom-by-atom
the re-grown structure. A combination of these nano-scale etching and
re-knitting processes could lead to new graphene tailoring approaches.Comment: 11 pages, 4 figure
Current Account Imbalances and Structural Adjustment in the Euro Area: How to Rebalance Competitiveness
Low international competitiveness of a set of euro area countries, which have become evident by large current account deficits and rising risk premiums on government bonds, is one of the most challenging economic policy issues for Europe. We analyse the role of private restructuring and public structural reforms for the urgently needed readjustment of intra-euro area imbalances. A panel regression reveals a significant impact of private restructuring and public structural reforms on intra-euro area competitiveness. This implies that private restructuring and public reforms are rather than public transfers the best way to preserve long-term economic stability in Europe
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