University of Windsor

About: University of Windsor is a education organization based out in Windsor, Ontario, Canada. It is known for research contribution in the topics: Population & Argumentation theory. The organization has 10654 authors who have published 22307 publications receiving 435906 citations. The organization is also known as: UWindsor & Assumption University of Windsor.

Divergence thresholds and divergent biodiversity estimates: can metabarcoding reliably describe zooplankton communities?

Abstract: DNA metabarcoding is a promising method for describing communities and estimating biodiversity. This approach uses high-throughput sequencing of targeted markers to identify species in a complex sample. By convention, sequences are clustered at a predefined sequence divergence threshold (often 3%) into operational taxonomic units (OTUs) that serve as a proxy for species. However, variable levels of interspecific marker variation across taxonomic groups make clustering sequences from a phylogenetically diverse dataset into OTUs at a uniform threshold problematic. In this study, we use mock zooplankton communities to evaluate the accuracy of species richness estimates when following conventional protocols to cluster hypervariable sequences of the V4 region of the small subunit ribosomal RNA gene (18S) into OTUs. By including individually tagged single specimens and “populations” of various species in our communities, we examine the impact of intra- and interspecific diversity on OTU clustering. Communities consisting of single individuals per species generated a correspondence of 59–84% between OTU number and species richness at a 3% divergence threshold. However, when multiple individuals per species were included, the correspondence between OTU number and species richness dropped to 31–63%. Our results suggest that intraspecific variation in this marker can often exceed 3%, such that a single species does not always correspond to one OTU. We advocate the need to apply group-specific divergence thresholds when analyzing complex and taxonomically diverse communities, but also encourage the development of additional filtering steps that allow identification of artifactual rRNA gene sequences or pseudogenes that may generate spurious OTUs.

Nurses’ experiences with telephone triage and advice: a meta-ethnography

Abstract: purc-stephenson r.j. & thrasher c. (2010) Nurses’ experiences with telephone triage and advice: a meta-ethnography. Journal of Advanced Nursing66(3), 482–494. Abstract Aims. This study is a meta-ethnography of nurses’ experiences with telephone triage and advice and factors that facilitate or impede their decision-making process. Background. Telephone triage and advice services are a rapidly expanding development in health care. Unlike traditional forms of nursing practice, telenurses offer triage recommendations and advice to the general public without visual cues. Data sources. Published qualitative research on telephone triage and advice were sought from interdisciplinary research databases (1980–2008) and bibliographical reviews of retrieved studies. Review methods. Our systematic search identified 16 relevant studies. Two researchers independently reviewed, critically appraised, and extracted key themes and concepts from each study. We followed techniques of meta-ethnography to synthesize the findings, using both reciprocal and refutational translation to compare similar or contradictory findings, and a line-of-arguments synthesis. Results. We identified five major themes that highlight common issues and concerns experienced by telenurses: gaining and maintaining skills, autonomy, new work environment, holistic assessment, and stress and pressure. A line-of-arguments synthesis produced a three-stage model that describes the decision-making process used by telenurses and highlights how assessments largely depend on the ability to ‘build a picture’ of the patient and the presenting health issue. Conclusion. Telenurses experience a range of common concerns and issues which either impede or facilitate the decision-making process. Although ‘building a picture’ of the patient is key to making assessments over the telephone, final triage decisions are influenced by balancing the conflicting demands of being both carer and gatekeeper to limited healthcare services.