105 research outputs found

    Scaled-chrysophyte assemblage changes in the sediment records of lakes recovering from marked acidification and metal contamination near Wawa, Ontario, Canada

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    A remarkable example of point-source lake acidification and metal pollution, and subsequent recovery in limnological variables, has occurred in lakes near the former iron sintering plant at Wawa (Ontario, Canada). Surface water pH levels in some of these lakes have increased from 3 to 7 following local sulphur emission reductions with closure of industrial operations. Previous paleolimnological work documented striking successional changes in diatom species assemblages within dated sediment cores that could be related to past industrial activities. To gain additional insights into the chemical and biological recovery trajectories of the Wawa lakes, we used paleolimnological techniques to track euplanktonic scaled-chrysophyte (classes Chrysophyceae and Synurophyceae) species assemblage responses to historical water quality changes in five lakes. Coincident with the period of iron sintering from 1939 to 1998, striking successional changes were noted in the sedimentary profiles, with marked increases in the relative abundances of the acid- and metal-tolerant taxon Synura echinulata. The scaled chrysophyte changes pre-dated diatom responses, confirming the former’s status as reliable early warning indicators of lake acidification. Following closure of the sintering plant, species-specific chrysophyte responses to decreased emissions varied amongst the study lakes, perhaps reflecting differences in local bedrock geology and hydrological regime. Although some water chemistry variables may have recovered to near pre-industrial levels, similar to the diatom study, our data show that chrysophyte assemblages in the most recent sediments are now significantly different from pre-industrial assemblages

    The jellification of north temperate lakes.

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    Calcium (Ca) concentrations are decreasing in softwater lakes across eastern North America and western Europe. Using long-term contemporary and palaeo-environmental field data, we show that this is precipitating a dramatic change in Canadian lakes: the replacement of previously dominant pelagic herbivores (Ca-rich Daphnia species) by Holopedium glacialis, a jelly-clad, Ca-poor competitor. In some lakes, this transformation is being facilitated by increases in macro-invertebrate predation, both from native (Chaoborus spp.) and introduced (Bythotrephes longimanus) zooplanktivores, to which Holopedium, with its jelly coat, is relatively invulnerable. Greater representation by Holopedium within cladoceran zooplankton communities will reduce nutrient transfer through food webs, given their lower phosphorus content relative to daphniids, and greater absolute abundances may pose long-term problems to water users. The dominance of jelly-clad zooplankton will likely persist while lakewater Ca levels remain low.This work was primarily supported by grants from the Natural Sciences and Engineering Research Council of Canada and funding from the Ontario Ministry of the Environment.This is the accepted manuscript. The final version is available at http://rspb.royalsocietypublishing.org/content/282/1798/20142449

    Australia and Thailand - A Strategic Reset?

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    In this multi-author edition of the Centre of Gravity series, co-editors William Tow and Suphat Suphachalasai work with leading strategic thinkers to explore the relationship between Australia and Thailand

    Cross-Canada EMR Case Studies: Analysis of Physicians' Perspectives on Benefits and Barriers

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    Abstract Our objective was to provide physicians with practical information on best practices and lessons learned with regards to implementation and use of electronic medical record (EMR) systems in ambulatory clinical practice settings. Methodology: A cross-Canada EMR study-the first of its kind-used case study methodology to investigate how EMRs were implemented and used in primary care. Knowledge transfer methods included print and web publications by the Canadian Medical Association (CMA) and a workshop. Results: The 20 case studies informed us in detail of the critical success factors for implementation. These were validated and augmented through a workshop. Conclusions: Electronic medical record (EMR) uptake in Canada and the US significantly lags behind other countries. Hence, there is a need to spread the good news about the actual benefits of EMRs to patients, physicians and the health care system and to mitigate barriers to EMR adoption and use

    Disturbances across whole brain networks during reward anticipation in an abstinent addiction population.

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    The prevalent spatial distribution of abnormalities reported in cognitive fMRI studies in addiction suggests there are extensive disruptions across whole brain networks. Studies using resting state have reported disruptions in network connectivity in addiction, but these studies have not revealed characteristics of network functioning during critical psychological processes that are disrupted in addiction populations. Analytic methods that can capture key features of whole brain networks during psychological processes may be more sensitive in revealing additional and widespread neural disturbances in addiction, that are the provisions for relapse risk, and targets for medication development. The current study compared a substance addiction (ADD; n = 83) group in extended abstinence with a control (CON; n = 68) group on functional MRI (voxel-wise activation) and global network (connectivity) measures related to reward anticipation on a monetary incentive delay task. In the absence of group differences on MID performance, the ADD group showed reduced activation predominantly across temporal and visual regions, but not across the striatum. The ADD group also showed disruptions in global network connectivity (lower clustering coefficient and higher characteristic path length), and significantly less connectivity across a sub-network comprising frontal, temporal, limbic and striatal nodes. These results show that an addiction group in extended abstinence exhibit localised disruptions in brain activation, but more extensive disturbances in functional connectivity across whole brain networks. We propose that measures of global network functioning may be more sensitive in highlighting latent and more widespread neural disruptions during critical psychological processes in addiction and other psychiatric disorders

    Massively distributed authorship of academic papers

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    Wiki-like or crowdsourcing models of collaboration can provide a number of benefits to academic work. These techniques may engage expertise from different disciplines, and potentially increase productivity. This paper presents a model of massively distributed collaborative authorship of academic papers. This model, developed by a collective of thirty authors, identifies key tools and techniques that would be necessary or useful to the writing process. The process of collaboratively writing this paper was used to discover, negotiate, and document issues in massively authored scholarship. Our work provides the first extensive discussion of the experiential aspects of large-scale collaborative research.Peer ReviewedPostprint (author's final draft

    The state of the Martian climate

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    60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

    Crop Updates 2009 - Genetically Modified Crops, Nutrition, Soils, & Others

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    This session covers fifteen papers from different authors: 1. Performance of Canola Breeders Roundup Ready® canola hybrid CHYB-166 in 2008, Wallace Cowling, Canola Breeders Western Australia Pty Ltd 2. The implications of GM glyphosate resistant lupin, Art Diggle, Caroline Peek, Frank D’Emden, Fiona Evans, Bob French, Rob Grima, Sam Harburg, Abul Hashem,, John Holmes, Jeremy Lemon, Peter Newman, Janet Paterson, Steve Penny,Department of Agriculture and Food, Peter Portmann, Agriconnect 3. Nufarm Roundup Ready® Canola Systems Trials— 2008 Mark Slatter, Research and Development Officer, Victoria, Nufarm (0438 064 845) Angus MacLennan, Business Development Manager, New South Wales, Nufarm (0408 358 024) Cooperators: Monsanto, Nuseed, Pacific Seeds, Pioneer Seeds 4. Roundup Ready® canola—2008 Limited Commercial Release. Getting the system right, Andrew Wells and Mark Slatter, Nufarm Australia Limited (Reprint from 2008 GRDC Cropping Updates with Introductory note) NUTRITION 5. Fertilising in a changing price environment, Bill Bowden1, Wayne Pluske2 and Jeremy Lemon1, 1Department of Agriculture and Food, 2Back Paddock Company 6. Making better fertiliser for Western Australian cropping systems, Wen Chen1 2, Geoff Anderson1, Ross Brennan1and Richard Bell2 1Department of Agriculture and Food, 2School of Environmental Science, Murdoch University 7. The nitrogen fertiliser replacement value of biosolids from wastewater treatment, Hannah Rigby1, Deborah Pritchard1, David Collins1, Katrina Walton2, David Allen2 and Nancy Penney31School of Agriculture and Environment,Curtin University of Technology, Muresk Campus, 2Chemistry Centre of Western Australia 3Water Corporation of Western Australia 8. Fertilising to soil type (usually) pays, Michael Robertson, Bill Bowden and Roger Lawes, CSIRO, Floreat and Department of Agriculture and Food SOILS 9. Management of subsoil acidity and compaction using a combination of lime, deep ripping and controlled traffic, Stephen Davies, Chris Gazey, Breanne Best and David Gartner, Department of Agriculture and Food 10. Optimising gypsum applications through remote sensing and Variable Rate Technology, Frank D’Emden, Department of Agriculture and Food and Quenten Knight,Precision Agronomics Australia 11. Case study of a 17 year agricultural lime trial, Chris Gazey1, Joel Andrew2and Ryan Pearce3 1Department of Agriculture and Food; 2Precision SoilTech; 3ConsultAg 12. Soil organic carbon in WA agricultural soils, FC Hoyle and A Bennett, Department of Agriculture and Food OTHER 13. Is the no-till revolution complete in WA? Frank D’Emden1, Rick Llewellyn2 and Ken Flower3 1Department of Agriculture and Food, 2CSIRO Sustainable Ecosystems, 3University of Western Australia 14. Progression Planning (The Concept), Julian Krieg and Owen Catto, Wheatbelt Men’s Health 15. Is the Department of Agriculture and Food still a primary source of cropping information? Cindy Parsons, Department of Agriculture and Foo
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