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31.
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Lyndsay A. Cartwright Sue Hayes Douglas C. Tozer Dan Clayton Mary-Ann Burns Dena Lewis Noah Gaetz Namrata Shrestha 《Journal of Great Lakes research》2021,47(2):273-282
Beneficial use impairments (BUIs) under the Great Lakes Water Quality Agreement identify environmental issues requiring remedial action within the Great Lakes Areas of Concern (AOCs). We conducted this study to support the assessment of the wildlife component of BUI 3: degradation of fish and wildlife populations. We compared bird and amphibian (frogs and toads) data from the Toronto and Region Conservation Authority’s Terrestrial Long-term Monitoring Program in the Toronto and Region AOC to an adjacent, but otherwise similar, reference watershed, Duffins Creek. Twelve of 13 targets were met within the AOC for forest bird, wetland bird, meadow bird and amphibian populations based on averages of mean annual values at sites within the AOC that were within two standard deviations of averages at sites in the Duffins Creek reference watershed between 2008 and 2017. Even though wildlife populations within the AOC were within the normal range of variability expected from a reference watershed, they were often at lower levels than within the Duffins Creek reference watershed. In addition, forest bird and amphibian populations were negatively affected by urbanization within the AOC and meadow bird indices declined. We conclude that while wildlife populations within the AOC currently meet targets for BUI 3, they continue to be negatively impacted by numerous stressors that are primarily related to past and ongoing urbanization. Thus, continued restoration of wildlife habitat and protection of existing habitat within the AOC is highly recommended. 相似文献
33.
Railway Engineering Science - Electrified railways are becoming a popular transport medium and these consume a large amount of electrical energy. Environmental concerns demand reduction in energy... 相似文献
34.
Silicon - The performance comparison and the temperature profile of AlGaN/GaN HEMT on different substrates are investigated. It results the maximum drain-source current (IDS) of 1.08 A/mm, 1.04... 相似文献
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Alveolar Type II cells in the rat respond to severe, acute ozone injury (3 ppm ozone for eight hours) by increasing their
intracellular pool of surfactant; however, the newly stored surfactant is abnormal in composition. Lamellar bodies isolated
between 24 and 96 hours after ozone exposure contained significantly more cholesterol in relation to phosphatidylcholine than
did controls. By contrast, the cholesterol content of surfactant isolated from alveolar lavage remained unchanged throughout
an 8-day post-ozone period. The total protein content of lamellar bodies in relation to phosphatidylcholine was significantly
decreased at 24 and 48 hours post-ozone. Analysis of lamellar body proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis
revealed that the amount of a 14 kDa proteolipid was greatly reduced at the end of the eight-hour ozone exposure and remained
low for at least 48 hours. This proteolipid appeared to be a specific lamellar body component since it was not detected in
extracellular surfactant. The findings indicate that oxidative alveolar stress initiates characteristic alterations in both
lipid and protein constituents of stored surfactant, without perturbation in the composition of extracellular surfactant. 相似文献
38.
Morphology and fracture mechanisms in two nanoclay‐filled epoxy systems were investigated using both microscopy and spectroscopy tools. Clay exfoliation was achieved using a series of sample preparation steps, and confirmed using wide angle X‐ray diffraction (XRD) and transmission electron microscopy (TEM) techniques. Significant improvement in modulus was obtained when clay exfoliation was achieved. Incorporation of core‐shell rubber (CSR) in both caly‐filled epoxy systems leads to greatly enhanced fracture toughness. Optical microscopy and TEM observations of the CSR‐modified nanocomposites suggest that CSR cavitation. shear yielding of the matrix, clay layer delamination. CSR bridging, crack bifurcation. and crack deflection are among the operative toughening mechanisms observed, depending on the nature of the epoxy matrix utilized. 相似文献
39.
McManis G. E. Fletcher A. N. Bliss D. E. Miles M. H. 《Journal of Applied Electrochemistry》1986,16(2):229-238
Copper and nickel may be electrodeposited from their ions in solution in nitrate-amide melts at room temperature. In the ammonium nitrate-acetamide-urea melt at 23°C, the reduction to the metal competes with the corrosion reaction at low rates and with the reduction of the ammonium and nitrate ions of the melt at high current densities. Two distinct types of nickel complexes are found in solution. The nickel complex formed by the corrosion reaction is bound by at least one ammonia ligand. Nickel complexes formed by dissolving the halide in the melt show evidence of coordination by less strongly bounding ligands, probably by amides. Similarly, the visible spectra of copper chloride in solution suggest that the cupric ions are coordinated primarily by amides. The copper corrosion reaction produces a complex with a spectra distinctly different from that of cupric chloride in solution. The shift in absorption maxima suggests that the copper complex formed by the corrosion reaction has at least one ammonia ligand in the coordination sphere. 相似文献
40.
Sue McKnight 《New Review of Information Networking》2013,18(1):3-16
The purpose statement of Deakin University Library is ‘We help people learn.’ This applies equally to on or off‐campus students, which has meant that the Library has strived to provide innovative resources and services to break down the barriers of geography and time experienced by our remote students. With the advances in information and communication technologies, Deakin University Library has been able to capitalise on these developments to deliver electronic services to both on and off‐campus students, thus complementing the valuable services provided by the Library team. While the services provided through the virtual or digital library are a great leap forward, providing access to a wide range of resources and services 24 hours per day x 7 days per week, these services must be seen in conjunction with the professional assistance provided by librarians. Deakin University Library's success is in its customer focus and the value added digital services available through the virtual campus. 相似文献