University of Guelph

About: University of Guelph is a education organization based out in Guelph, Ontario, Canada. It is known for research contribution in the topics: Population & Gene. The organization has 26542 authors who have published 50553 publications receiving 1715255 citations. The organization is also known as: U of G & Guelph University.

Novel weapons: invasive plant suppresses fungal mutualists in america but not in its native europe

Abstract: Why some invasive plant species transmogrify from weak competitors at home to strong competitors abroad remains one of the most elusive questions in ecology. Some evidence suggests that disproportionately high densities of some invaders are due to the release of biochemicals that are novel, and therefore harmful, to naive organisms in their new range. So far, such evidence has been restricted to the direct phytotoxic effects of plants on other plants. Here we found that one of North America's most aggressive invaders of undisturbed forest understories, Alliaria petiolata (garlic mustard) and a plant that inhibits mycorrhizal fungal mutualists of North American native plants, has far stronger inhibitory effects on mycorrhizas in invaded North American soils than on mycorrhizas in European soils where A. petiolata is native. This antifungal effect appears to be due to specific flavonoid fractions in A. petiolata extracts. Furthermore, we found that suppression of North American mycorrhizal fungi by A. petiolata corresponds with severe inhibition of North American plant species that rely on these fungi, whereas congeneric European plants are weakly affected. These results indicate that phytochemicals, benign to resistant mycorrhizal symbionts in the home range, may be lethal to naive native mutualists in the introduced range and indirectly suppress the plants that rely on them.

For Slow Scholarship: A Feminist Politics of Resistance through Collective Action in the Neoliberal University

Abstract: The neoliberal university requires high productivity in compressed time frames. Though the neoliberal transformation of the university is well documented, the isolating effects and embodied work conditions of such increasing demands are too rarely discussed. In this article, we develop a feminist ethics of care that challenges these working conditions. Our politics foreground collective action and the contention that good scholarship requires time: to think, write, read, research, analyze, edit, organize, and resist the growing administrative and professional demands that disrupt these crucial processes of intellectual growth and personal freedom. This collectively written article explores alternatives to the fast-paced, metric-oriented neoliberal university through a slow-moving conversation on ways to slow down and claim time for slow scholarship and collective action informed by feminist politics. We examine temporal regimes of the neoliberal university and their embodied effects. We then consider strategies for slowing scholarship with the objective of contributing to the slow scholarship movement. This slowing down represents both a commitment to good scholarship, teaching, and service and a collective feminist ethics of care that challenges the accelerated time and elitism of the neoliberal university. Above all, we argue in favor of the slow scholarship movement and contribute some resistance strategies that foreground collaborative, collective, communal ways forward.

Towards standards for human fecal sample processing in metagenomic studies

Abstract: Technical variation in metagenomic analysis must be minimized to confidently assess the contributions of microbiota to human health. Here we tested 21 representative DNA extraction protocols on the same fecal samples and quantified differences in observed microbial community composition. We compared them with differences due to library preparation and sample storage, which we contrasted with observed biological variation within the same specimen or within an individual over time. We found that DNA extraction had the largest effect on the outcome of metagenomic analysis. To rank DNA extraction protocols, we considered resulting DNA quantity and quality, and we ascertained biases in estimates of community diversity and the ratio between Gram-positive and Gram-negative bacteria. We recommend a standardized DNA extraction method for human fecal samples, for which transferability across labs was established and which was further benchmarked using a mock community of known composition. Its adoption will improve comparability of human gut microbiome studies and facilitate meta-analyses.

ABC efflux pump-based resistance to chemotherapy drugs.

Abstract: 3.2. Other Potential in vivo Functions of Pgp 2992 3.3. Physiological Role of ABCG2 2992 3.4. Physiological Role of MRP1 2992 4. Structure of ABC Superfamily Drug Efflux Pumps 2992 4.1. Domain Structure of ABC Proteins 2992 4.2. Structure of Entire Bacterial ABC Proteins 2993 4.3. Structure of Pgp, MRP1, and ABCG2 2994 5. Substrate Specificity of ABC Drug Efflux Pumps 2995 5.1. MDR Spectrum Substrates 2995 5.2. Binding and Transport of Drugs 2998 5.3. Multidrug-Binding Pockets 2998 6. Catalytic Cycle of ABC Drug Efflux Pumps 3000 6.1. ATP Binding and Hydrolysis 3000 6.2. Occluded Nucleotide Conformation of Pgp 3000 6.3. Role of NBD Dimerization and the Occluded Conformation in the Catalytic Cycle of Pgp 3000

Environmental barcoding: a next-generation sequencing approach for biomonitoring applications using river benthos.

Abstract: Timely and accurate biodiversity analysis poses an ongoing challenge for the success of biomonitoring programs. Morphology-based identification of bioindicator taxa is time consuming, and rarely supports species-level resolution especially for immature life stages. Much work has been done in the past decade to develop alternative approaches for biodiversity analysis using DNA sequence-based approaches such as molecular phylogenetics and DNA barcoding. On-going assembly of DNA barcode reference libraries will provide the basis for a DNA-based identification system. The use of recently introduced next-generation sequencing (NGS) approaches in biodiversity science has the potential to further extend the application of DNA information for routine biomonitoring applications to an unprecedented scale. Here we demonstrate the feasibility of using 454 massively parallel pyrosequencing for species-level analysis of freshwater benthic macroinvertebrate taxa commonly used for biomonitoring. We designed our experiments in order to directly compare morphology-based, Sanger sequencing DNA barcoding, and next-generation environmental barcoding approaches. Our results show the ability of 454 pyrosequencing of mini-barcodes to accurately identify all species with more than 1% abundance in the pooled mixture. Although the approach failed to identify 6 rare species in the mixture, the presence of sequences from 9 species that were not represented by individuals in the mixture provides evidence that DNA based analysis may yet provide a valuable approach in finding rare species in bulk environmental samples. We further demonstrate the application of the environmental barcoding approach by comparing benthic macroinvertebrates from an urban region to those obtained from a conservation area. Although considerable effort will be required to robustly optimize NGS tools to identify species from bulk environmental samples, our results indicate the potential of an environmental barcoding approach for biomonitoring programs.