224 research outputs found
First flea (Siphonaptera) records for Kanuti National Wildlife Refuge, Central Alaska
Kanuti National Wildlife Refuge (KNWR) was established in 1980 in Central Alaska. Collections of mammal fleas began in 1991. Six species resulted: Catallagia dacenkoi Ioff, Corrodopsylla curvata (Rothschild), Ctenophthalmus pseudagyrtes Baker, Megabothris calcarifer (Wagner), Amalaraeus dissimilis (Jordan) and Peromyscopsylla ostsibirica (Scalon). Ten species of fleas were previously recorded from the upper Koyukuk River watershed. One female specimen each of C. curvata and Ct. pseudagyrtes from the KNWR are the only new fleas added to the upper watershed list
First flea (Siphonaptera) records for Kanuti National Wildlife Refuge, Central Alaska
Kanuti National Wildlife Refuge (KNWR) was established in 1980 in Central Alaska. Collections of mammal fleas began in 1991. Six species resulted: Catallagia dacenkoi Ioff, Corrodopsylla curvata (Rothschild), Ctenophthalmus pseudagyrtes Baker, Megabothris calcarifer (Wagner), Amalaraeus dissimilis (Jordan) and Peromyscopsylla ostsibirica (Scalon). Ten species of fleas were previously recorded from the upper Koyukuk River watershed. One female specimen each of C. curvata and Ct. pseudagyrtes from the KNWR are the only new fleas added to the upper watershed list
Mammal Fleas (Siphonaptera: Ceratophyllidae) New for Alaska and the Southeastern Mainland Collected During Seven Years of a Field Survey of Small Mammals
Ten taxa of mammal fleas were among 124 collection records from 12 host species (one shrew, nine rodents and two carnivores), at 72 localities on the southeastern Alaska mainland in 1989 and during an extensive survey of mammals in 1992-1995 and 1997-1999. Megabothris asio megacolpus (Jordan) ex Microtus pennsylvanicus (Ord), Malaraeus telchinus (Rothschild) ex Peromyscus keeni (Rhoads) and Clethrionomys gapperi (Vigors) are new fleas for Alaska. Orchopeas caedens (Jordan) ex Tamiasciurus hudsonicus (Erxleben) is a new flea for southeastern Alaska. Synaptomys borealis (Richardson) is a new host record for Opisodasys k. keeni (Baker). The other six taxa of fleas collected were Hystrichopsylla dippiei spinata Holland, H. o. occidentalis Holland, Catallagia charlottensis (Baker), Ceratophyllus ciliatus protinus Jordan, Megabothris abantis (Rothschild) and Opisodasys vesperalis (Jordan). Of these, H. o. occidentalis, C. charlottensis and M. abantis have seven new host records for the southeastern Alaska mainland. Distribution patterns of the fleas and their host relationships in North America are discussed
Envisioning sustainable tourism futures: An evaluation of the futures wheel method
Methods for researching the future have grown both in variety and rigour, offering new opportunities for understanding sustainable tourism. This paper discusses the value of futures research as a tool for envisioning and planning sustainable tourism futures but observes that there is greater potential for the use of futures methods in tourism. The aim of this paper is to evaluate the usefulness of a particular method known as the futures wheel as a sustainable planning tool for tourism decision makers and researchers. The futures wheel method is combined with a grounded theory approach to capture and distil the tacit knowledge of three 'expert' think tanks. The evaluation suggests that the futures wheel is a useful tool for researching sustainable tourism futures but that its potential may be enhanced if it can be combined with other futures research methods
Sample richness and genetic diversity as drivers of chimera formation in nSSU metagenetic analyses
Eukaryotic diversity in environmental samples is often assessed via PCR-based amplification of nSSU genes. However, estimates of diversity derived from pyrosequencing environmental data sets are often inflated, mainly because of the formation of chimeric sequences during PCR amplification. Chimeras are hybrid products composed of distinct parental sequences that can lead to the misinterpretation of diversity estimates. We have analyzed the effect of sample richness, evenness and phylogenetic diversity on the formation of chimeras using a nSSU data set derived from 454 Roche pyrosequencing of replicated, large control pools of closely and distantly related nematode mock communities, of known intragenomic identity and richness. To further investigate how chimeric molecules are formed, the nSSU gene secondary structure was analyzed in several individuals. For the first time in eukaryotes, chimera formation proved to be higher in both richer and more genetically diverse samples, thus providing a novel perspective of chimera formation in pyrosequenced environmental data sets. Findings contribute to a better understanding of the nature and mechanisms involved in chimera formation during PCR amplification of environmentally derived DNA. Moreover, given the similarities between biodiversity analyses using amplicon sequencing and those used to assess genomic variation, our findings have potential broad application for identifying genetic variation in homologous loci or multigene families in general
Identification and rapid mapping of a gene conferring broad-spectrum late blight resistance in the diploid potato species <i>Solanum verrucosum</i> through DNA capture technologies
Identification of LukPQ, a novel, equid-adapted leukocidin of Staphylococcus aureus.
Bicomponent pore-forming leukocidins are a family of potent toxins secreted by Staphylococcus aureus, which target white blood cells preferentially and consist of an S- and an F-component. The S-component recognizes a receptor on the host cell, enabling high-affinity binding to the cell surface, after which the toxins form a pore that penetrates the cell lipid bilayer. Until now, six different leukocidins have been described, some of which are host and cell specific. Here, we identify and characterise a novel S. aureus leukocidin; LukPQ. LukPQ is encoded on a 45 kb prophage (ΦSaeq1) found in six different clonal lineages, almost exclusively in strains cultured from equids. We show that LukPQ is a potent and specific killer of equine neutrophils and identify equine-CXCRA and CXCR2 as its target receptors. Although the S-component (LukP) is highly similar to the S-component of LukED, the species specificity of LukPQ and LukED differs. By forming non-canonical toxin pairs, we identify that the F-component contributes to the observed host tropism of LukPQ, thereby challenging the current paradigm that leukocidin specificity is driven solely by the S-component
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