1,042 research outputs found
Challenging the gold standard: alternatives to the collison for aerosol generation in research
No full textAnimal studies to demonstrate efficacy of medical countermeasures against respiratory disease or biodefense threats require exposure of animals to aerosolized viruses and bacteria. Prior studies have shown that the choice of culture media and relative humidity in the aerosol chamber can impact the dose of infectious agent delivered to animals. Most infectious aerosol studies have involved the use of Collison jet nebulizers which create a small, relatively monodisperse aerosol that targets the deep lung. Collison nebulizers require a relatively large volume of infectious agent and the jets that create the aerosol may damage the agent being aerosolized. Damage resulting from the nebulizer can impact agent infectivity and virulence as well as study reproducibility. We compared the Blaustein Atomizing Module (BLAM) and the Aeroneb, a vibrating-mesh nebulizer, to the existing ‘gold standard’ Collison nebulizer for generation of small particle aerosols containing either a bacterium, F. tularensis, or a virus, influenza or Rift Valley Fever Virus (RVFV) in different exposure chambers. Aerosol performance was assessed by comparing the spray factor (the ratio between the aerosol concentration of an agent and the concentration of the agent in the nebulizer), the reduction in pathogen viability, and the aerosol efficiency (the ratio of the actual aerosol concentration to the theoretical aerosol concentration. In the NOT, the Collison had superior aerosol performance compared to the BLAM and the Aeroneb, while the Aeroneb had superior aerosol performance comparted to the Collison in the whole-body and head-only chambers. Regression analysis revealed increased humidity was associated with improved aerosol performance of F. tularensis, but no environmental factors were associated with improved aerosol performance of influenza or RVFV. This data demonstrates that there is no ‘one size fits all’ choice for aerosol generators, and that further characterization of aerosol generators and factors that affect aerosol performance are needed to improve selection of aerosol equipment. The public health significance of this research is to contribute to the characterization of available aerosol generators to optimize aerosol experiments for a more robust experimental design for developing animal models of respiratory infections and developing therapeutics and vaccines against potential biological weapons
Bulletin: Number 623: Experiments with Commercial Nitrogenous Fertilizers on Apple Orchards
No full text36 pages, 1 article*Experiments with Commercial Nitrogenous Fertilizers on Apple Orchards* (Harlan, J. D.; Collison, R. C.) 34 page
Bulletin: Number 562: High-Nicotine Tobacco
No full text19 pages, 1 article*High-Nicotine Tobacco* (Collison, R. C.; Harlan, J. D.; Streeter, L. R.) 17 page
Bulletin: Number 647: Winter Injury of Baldwin Apple Trees and its Relation to Previous Tree Performance and Nutritional Treatment
No full text13 pages, 1 article*Winter Injury of Baldwin Apple Trees and its Relation to Previous Tree Performance and Nutritional Treatment* (Collison, R. C.; Harlan, J. D.) 11 page
Bulletin: Number 629: Some Facts About Soil Management in a New York Orchard
No full text20 pages, 1 article*Some Facts About Soil Management in a New York Orchard* (Collison, R. C.; Harlan, J. D.) 18 page
Bulletin: Number 503: Final Report on the Cooperative Experiments in Orchard Fertilization
No full text30 pages, 1 article*Final Report on the Cooperative Experiments in Orchard Fertilization* (Collison, R. C.; Harlan, J. D.) 29 page
Bulletin: Volume 646: Fertilizer Responses of Baldwin Apple Trees on an Acid Soil
No full text24 pages, 1 article*Fertilizer Responses of Baldwin Apple Trees on an Acid Soil* (Collison, R. C.; Harlan, J. D.) 22 page
William Henry Collison
No full textThe chapter, "William Henry Collison" was written by Gail Edwards (Douglas College Faculty). This new volume of the Dictionary of Canadian Biography / Dictionnaire Biographique du Canada (DCB / DBC) presents well-written, carefully documented and meticulously edited biographies of Canadians from all walks of life. Its literary and scholarly standards make it, like its predecessors, the definitive biographical reference for its period of history. The 619 biographies by 446 authors present a panoramic view of the origins of modern Canada, its political landscapes, economic changes, educational institutions, cultural developments, and athletic achievements. The volume’s coverage is inclusive, ranging from murderers to artists, from business magnates to religious leaders, from Canada’s First Peoples to new immigrants. There are labour leaders, farmers, feminists, and naturalists as well as all the prominent leaders in all aspects of Canadian life.
The dominant theme of this volume is the emergence of a country engrossed by material gains and aware of broadening horizons. Sir Clifford Sifton, federal minister of the interior, Sir Lomer Gouin, premier of Quebec, and Sir Robert Bond, premier of Newfoundland, symbolize this age of development. The lives of Sir Adam Beck, father of Ontario Hydro, Gordon Morton McGregor, founder of the Ford Motor Company of Canada, and Alexander Graham Bell, inventor of the telephone, illustrate how new technologies harnessed natural energy sources and created new ways to communicate. Such innovations drove the transformation of Canada in the early years of the twentieth century.
An expanding nation required thousands of new people to answer the demands of the agricultural enterprises in the west, the manufacturing industries of central Canada, and the fishing and lumbering businesses of British Columbia and the Atlantic region. Many newcomers were drawn from eastern Europe and Asia as well as the British Isles and western Europe, traditionally the homelands of new Canadians. The Doukhobor leader Peter Vasil’evich Verigin, the housemaid Angelina Napolitano, the Chinese teacher and merchant Yip Sang, and the Orthodox clergyman Nestor Dmytriw all took their places in the increasingly complex ethnic mosaic.
Social and economic changes inspired demands for other types of change. The movement of women into the professions is exemplified by the life of Clara Brett Martin, the first woman called to the bar in Canada. Jeanne Lajoie, an embattled Franco-Ontarian teacher, joins writers Sara Jeannette Duncan, Félicité Angers (known as Laure Conan), Joséphine Marchand (Dandurand) and Marjorie Lowry Christie Pickthall in the cast of women prominent in this volume. Among those representing arts and sports are the painter James Wilson Morrice and the brilliant goalkeeper Georges Vézina.
Without question Volume XV of the DCB/DBC will take its place as one of the finest to appear in this distinguished ongoing series of Canadian lives. --From publisher description.book chapterPublished
An electrostatic model for the determination of magnetic anisotropy in dysprosium complexes
No full textUnderstanding the anisotropic electronic structure of lanthanide complexes is important in areas as diverse as magnetic resonance imaging, luminescent cell labelling and quantum computing. Here we present an intuitive strategy based on a simple electrostatic method, capable of predicting the magnetic anisotropy of dysprosium(III) complexes, even in low symmetry. The strategy relies only on knowing the X-ray structure of the complex and the well-established observation that, in the absence of high symmetry, the ground state of dysprosium(III) is a doublet quantized along the anisotropy axis with an angular momentum quantum number mJ=± 15 / 2. The magnetic anisotropy axis of 14 low-symmetry monometallic dysprosium(III) complexes computed via high-level ab initio calculations are very well reproduced by our electrostatic model. Furthermore, we show that the magnetic anisotropy is equally well predicted in a selection of low-symmetry polymetallic complexes
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