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Geospatial data for developing nutrient SPARROW models for the Midcontinental region of Canada and the United States
No full textThrough the International Watersheds Initiative of the International Joint Commission (IJC), the Spatially-Referenced Regressions on Watershed attributes (SPARROW) model developed by the U.S. Geological Survey (USGS) is being applied to the Great Lakes, Rainy River \u2013 Lake of the Woods and Red-Assiniboine basins. The objective of this binational application of the SPARROW model is to better understand and quantify the sources of phosphorus (P) and nitrogen (N) that contribute to regional water quality issues like algal blooms and eutrophication in Lake Erie and other parts of the Great Lakes, as well as Lake of the Woods. Led by the IJC, a team of researchers from the National Research Council of Canada \u2013 Ocean, Coastal and River Engineering Research Centre, USGS, and IJC are extending the SPARROW modelling work previously completed for the Red-Assiniboine basin and the U.S. portions of the Great Lakes, Ohio, Upper Mississippi, and Souris-Red-Rainy river basins to cover all of the Great Lakes, Rainy River \u2013 Lake of the Woods and Red-Assiniboine basins. The current effort is termed the Midcontinent SPARROW modelling study.
This report describes the data used to develop the Midcontinent SPARROW models, specifically the sources of original data, assembling the data, and the processing and harmonization required between the U.S. and Canada data needed to produce these models. Details provided include the:
\u2022 development of a digital stream network and related catchments \u2013 most significantly in the Canadian regions of the Great Lakes and Rainy River \u2013 Lake of the Woods basins where these data were not available to create a seamless binational network across the model domain;
\u2022 calculation of variables to aid in the determination of in-stream and in-reservoir decay of P and N;
\u2022 quantification of Canadian diversions within the Midcontinental region (i.e., Lake St. Joseph, Long Lake and the Ogoki Reservoir);
\u2022 development of binational input nutrient sources considered for model development (i.e., land cover, inorganic farm fertilizer, manure, atmospheric deposition, point source pollution from wastewater treatment plants and contribution from non-modelled watersheds); and
\u2022 development of delivery variables considered to be most predominant (i.e., temperature, precipitation and ensuing runoff, soil permeability and clay content, slope of the catchments, and tile drainage).
The majority of the geospatial data collection and processing was required for Canadian datasets because many of the U.S. datasets were already assembled for previous SPARROW model applications in the U.S. The task of harmonizing data between the U.S. and Canada was important to ensure consistency of the datasets used in the models. The harmonized digital stream network, delineated catchments and input data for each catchment (i.e., source and delivery variables), created for the Midcontinent SPARROW models, are available for download at url https://doi.org/10.4224/300.0001This publication describes the development of this dataset : (2018) Binational dataset used to develop nutrient SPARROW models for the Midcontinental region of Canada and the United States. National Research Council CanadaCette publication d\ue9crit le d\ue9veloppement de l'ensemble de donn\ue9es suivant : (2018) Binational dataset used to develop nutrient SPARROW models for the Midcontinental region of Canada and the United States. National Research Council CanadaPeer reviewed: YesNRC publication: Ye
Update on the benefits and mechanisms of action of the bioactive vegetal alkaloid berberine on lipid metabolism and homeostasis
No full textElevation of circulating levels of blood cholesterol, especially LDL cholesterol, and/or the decrease of HDL cholesterol levels have long been recognized as primary risk factors for developing atherosclerosis that leads to cardiovascular and cerebrovascular disease. Hypertriglyceridemia is an independent risk factor that is known to contribute to the development of atherosclerosis. Thus, various interventional efforts aimed at reducing hypercholesterolemia and hypertriglyceridemia have been practiced clinically for decades to reduce morbidity and mortality risk associated with deleterious cardiovascular and cerebrovascular events. As such, many drugs have been developed and clinically used to treat hypocholesteremia and/or hypertriglyceridemia; however, dietary approaches including supplements along with changes in nutrition and lifestyle have become increasingly attractive and acceptable methods used to control borderline or moderately increased levels of blood cholesterol and triacylglycerols. In this regard, the use of a plant/herbal bioactive compound, berberine (BBR), has recently been studied extensively in terms of its efficacy as well as its mechanisms of action and safety as an alternative intervention that beneficially modulates blood lipids. The aim of this review is to provide a comprehensive update on BBR research, new concepts and directions in terms of product development and current challenges, and future prospects of using BBR to manage diseases and complications associated with dyslipidemia.Peer reviewed: YesNRC publication: Ye
Carrageenans: new tools for new applications
No full textCarrageenan is the generic name given to a family of sulfated polysaccharides extracted from some red seaweeds (Rhodophyta). They are made of repeating d\u2010galactose units linked alternately via \u3b1\u20101, 3 and \u3b2\u20101, 4 linkages. Units can have various sulfation patterns and often the \u3b1\u2010d\u2010galactose moiety is replaced by a 3,6\u2010anhydro\u2010\u3b1\u2010d\u2010galactose moiety. Carrageenans have long been used in the food industry (E407), in drug formulations, and in cosmetic products for their texturizing and gelling properties. Novel applications of carrageenans are moving toward the use of designed poly\u2010 and oligosaccharides that have specific functionality. In this respect, the use of specific carrageenan\u2010modifying enzymes is essential. There are two distinctive sets of enzymes: those that desulfate (sulfatases and sulfurylases) and the carrageenan hydrolases, also called carrageenases. These enzymes are used to produce specific oligosaccharides that are gaining in importance as they display biological activities in human health and plant growth and protection. The sulfurylases and sulfatases are able to specifically biochemically convert carrageenans into another carrageenan form. In this chapter, we review all the enzymes that are now available to bioconvert carrageenans, and we also present some of their possible uses. Perspectives of blue technology rely on potent analytical methods for in\u2010depth studies on the enzymatic modifications. Thus, the three main spectroscopic methods (infrared, nuclear magnetic resonance, and mass spectrometry) used for this purpose are presented.Peer reviewed: YesNRC publication: Ye
Concept to commercialization of an artifact for evaluating three-dimensional imaging systems per ASTM E3125-17
No full text\u2022 The relative-ra nge en-or test is one of several tests described in the ASTM E3 l 25-2017 standard for perfonnance evaluation of sphe1ical coordinate 3D imaging systems such as ten-estrial laser scanners (TLS). \u2022 Using a simple planar/plate target requires careful alignment of the targe!at each position of the relative-range en-or test which is labor intensive and time consuming. \u2022 We have designed a new artifact, called the plate-sphere target, that allows the realization of the relative-range error tests quickly and efficiently without the need for aligrunent at each position of the test. This new a1tifact significantly reduces the time required to pe1fonn the test, from a malter of hours to less than 30 minutes, thus saving users and manufacturers of TLSs considerable time and money. \u2022 The plate-sphere target was conceived at the National lnstitute of Standards and Technology (NIST), improved based on feedback from collaborators at the Nat ional Research Council (NRC) of Canada and TLS manufacturers, and commercialized by Bal-tee lnc.Peer reviewed: YesNRC publication: Ye
Calibration of electricity meters with digital input
No full textOvcr the last dccades, prolifcration of harmon ie producin g loads in the electric power system is noticeable, duc to, in large part , increase of use of many power electronics devices. This tren d contin ues as the role of power electronics in Smart Grid developments is very important. The Smart Grid is also characterized by an ever incrcasing use of intelligent elcctron ic dcviccs (lEDs) for monitoring, control, protection and mctcrin g in digital su bstations. The IEDs, non-convcntiona l instrument transformcrs (NCITs) with digital output, and merging un its (M Us), opcrate with power system voltage and currcnt sa mplcd values (SVs) conforming to IEC 61850-9-2 format. The SVs a rc also used for revenue mctering by non-convcnti onal cncrgy mcters with digital inputs. The paper {discusses 1 invcstigatcs} the performance of c11crgy meters with digital inputs u11der 11011- sinusoidal waveform conditions.Peer reviewed: YesNRC publication: Ye
The envelope kinematics and a possible disk around the class 0 protostar within BHR7
No full textWe present a characterization of the protostar embedded within the BHR7 dark cloud, based on both photometric measurements from the near-infrared to millimeter and interferometric continuum and molecular line observations at millimeter wavelengths. We find that this protostar is a Class 0 system, the youngest class of protostars, measuring its bolometric temperature to be 50.5 K, with a bolometric luminosity of 9.3 L \u2609. The near-infrared and Spitzer imaging show a prominent dark lane from dust extinction separating clear bipolar outflow cavities. Observations of 13CO (), C18O (), and other molecular lines with the Submillimeter Array (SMA) exhibit a clear rotation signature on scales <1300 au. The rotation can be traced to an inner radius of ~170 au and the rotation curve is consistent with an R 121 profile, implying that angular momentum is being conserved. Observations of the 1.3 mm dust continuum with the SMA reveal a resolved continuum source, extended in the direction of the dark lane, orthogonal to the outflow. The deconvolved size of the continuum indicates a radius of ~100 au for the continuum source at the assumed distance of 400 pc. The visibility amplitude profile of the continuum emission cannot be reproduced by an envelope alone and needs a compact component. Thus, we posit that the resolved continuum source could be tracing a Keplerian disk in this very young system. If we assume that the continuum radius traces a Keplerian disk (R ~ 120 au) the observed rotation profile is consistent with a protostar mass of 1.0 M \u2609.Peer reviewed: YesNRC publication: Ye
The next generation Virgo Cluster survey (NGVS). XVIII. Measurement and calibration of surface brightness fluctuation distances for bright galaxies in Virgo (and beyond)
No full textWe describe a program to measure surface brightness fluctuation (SBF) distances to galaxies observed in the Next Generation Virgo Cluster Survey (NGVS), a photometric imaging survey covering 104 deg2 of the Virgo cluster in the u*, g, i, and z bandpasses with the Canada\u2013France\u2013Hawaii Telescope. We describe the selection of the sample galaxies, the procedures for measuring the apparent i-band SBF magnitude m-i, and the calibration of the absolute Mibar as a function of observed stellar population properties. The multiband NGVS data set provides multiple options for calibrating the SBF distances, and we explore various calibrations involving individual color indices as well as combinations of two different colors. Within the color range of the present sample, the two-color calibrations do not significantly improve the scatter with respect to wide-baseline, single-color calibrations involving u*. We adopt the (u*-z) calibration as a reference for the present galaxy sample, with an observed scatter of 0.11 mag. For a few cases that lack good u* photometry, we use an alternative relation based on a combination of (g-i) and (g-z) colors, with only a slightly larger observed scatter of 0.12 mag. The agreement of our measurements with the best existing distance estimates provides confidence that our measurements are accurate. We present a preliminary catalog of distances for 89 galaxies brighter than B T 48 13.0 mag within the survey footprint, including members of the background M and W Clouds at roughly twice the distance of the main body of the Virgo cluster. The extension of the present work to fainter and bluer galaxies is in progress.Peer reviewed: YesNRC publication: Ye
Handbook for small biomass gasification CHP in Canada: hazard mitigation, emissions and the regulatory landscape for small scale biomass gasification combined heat and power systems
No full textPeer reviewed: NoNRC publication: Ye
Important factors affecting the gouging abrasion resistance of materials
No full textGouging abrasion occurs in many processes in comminution where large and hard abrasives such as rocks/ores are handled with high contact or impact stresses. In the past decade or so, the National Research Council Canada has systematically investigated the gouging abrasion performance of a wide range of materials per the ASTM G81 standard testing method using a jaw crusher. Materials evaluated include carbon and low alloy steels, high alloy tool steels, austenitic manganese steel, white cast irons, austempered ductile irons, chromium carbide and tungsten carbide overlays. In this paper, the main test results are summarized and the key properties/characteristics that are conducive to enhancing materials\u2019 gouging abrasion resistance are discussed.Peer reviewed: YesNRC publication: Ye
Satellite-based InSAR monitoring of highway bridges: validation case study on the north channel bridge in Ontario, Canada
No full textA space-borne bridge displacement monitoring technology was demonstrated on a major highway bridge in Cornwall (Ontario, Canada) over a 15-month period. Two major challenges had to be overcome and solutions were identified and implemented. The first challenge related to the proper selection and analysis of satellite imagery to optimize the number and signal quality of point targets on the bridge for adequate movement detection and analysis. The second challenge was the comparison and validation of independent sets of data having different measurement methods, reference baselines, and distributions in space and time. The key findings include: (i) the regression analysis of interferometric synthetic aperture radar (InSAR) data from the satellite produced the best coherence when fitted against the following three independent variables: height, ambient temperature, and time; (ii) the bridge railings appeared to be excellent natural reflectors with their sharp edges and regular spacing along the bridge, showing a return of over 3,000 clear point targets to the satellite; (iii) the InSAR displacement thermal sensitivity data was found to compare very well to numerical modeling thermal data. The results show great promise and value in applying satellite-based technology for the remote monitoring of highway and railway bridges to alert engineers of excessive movement and, in turn, will help optimize preventive maintenance management, extend structural lifespan, minimize traffic disruptions due to late repair, and ensure structural integrity.Peer reviewed: YesNRC publication: Ye