749 research outputs found
Hearing on Non-point Source Pollution: The Impacts of Agriculture on Water Quality
No full textCongressional testimony by Robert W. Howarth, before the U.S. House of Representatives subcommittee on Water Resources & the Environment - The Impact of Agriculture on Water Quality. April 19, 2007
δ Orionis: Further temporal variability and evidence for small-scale structure in the interstellar medium
No full textWe report here the detection of both spatial and temporal variations in interstellar absorption in the line of sight to δ Orionis. First, we present new high-resolution (R≈110 000) observations of the interstellar D lines of Na i towards both δ Ori A and C. Comparison of these spectra highlights variations in absorption between the two stars, indicative of small-scale spatial structure in the interstellar medium in this direction over distances of less than ≈15 000 au (the projected separation of the two stars). Components with the largest Na i column densities and lowest velocity dispersions are, in general, found to be subject to the greatest differences; in fact the narrowest component detected is only observed in one of the sightlines. This effect has also been reported by Meyer & Blades. Secondly, we present new ultra-high-resolution (R≈900 000) Na i D1 observations and high-resolution (R≈110 000) Ca ii H & K observations of δ Ori A which, through ultra-high-resolution work conducted between 1994 and 2000, has been shown to exhibit a time-variable interstellar Na i absorption component. These new observations, while revealing the further reduction in intensity of the time-variable Na i absorption, indicate constant Ca ii absorption over the same period. This results in a dramatic reduction in the Na°/Ca+ abundance ratio, perhaps indicating the line of sight to be gradually probing a less-dense outer region of an absorbing filament
Robert Amos arts and culture reviews and commentaries
No full textThe articles in this collection relate to various aspects of the arts and cultural scene in Victoria in the early to mid 1980s, they include: book reviews, history of Chinatown, letters to the editor, local heritage sites, as well as group and solo art and design exhibitions. Some illustrations by Amos. Artists reviewed include: F.H. Varley, Fenwick Lansdowne, Walter Dexter, Phyllis Serota, Lincoln Clarkes, Vincent Varga, Miles Lowry, W. J. Phillips, Jerry Pethick, Herbert Siebner, Robert Bateman, Harry Heine, Toni Onley, Wayne Ngan, Glenn Howarth, E. J. Hughes, Michael Morris, Colin Graham, Max Maynard and the Island Illustrators Society; Galleries include: Stephen Lowe, Kyle's, North Park, Open Space, Maltwood (UVic), and the Art Gallery of Greater Victoria.Item consists of 208 freelance arts and cultural reviews and commentaries, written by artist and writer Robert Amos, dated 1982-1986. The articles were written primarily for Monday Magazine, however some items appeared in publications such as Canadian Collector. Scanned from photocopies, 214 pages. PDF can be searched by keyword.Loaned to UVic Archives for scanning by Robert Amos in 2011. 'With permission from Monday Magazine.UndergraduateUnreviewe
A new look at the pathogenesis of asthma
No full textAsthma is an inflammatory disorder of the conducting airways that has strong association with allergic sensitization. The disease is characterized by a polarized Th-2 (T-helper-2)-type T-cell response, but in general targeting this component of the disease with selective therapies has been disappointing and most therapy still relies on bronchodilators and corticosteroids rather than treating underlying disease mechanisms. With the disappointing outcomes of targeting individual Th-2 cytokines or manipulating T-cells, the time has come to re-evaluate the direction of research in this disease. A case is made that asthma has its origins in the airways themselves involving defective structural and functional behaviour of the epithelium in relation to environmental insults. Specifically, a defect in barrier function and an impaired innate immune response to viral infection may provide the substrate upon which allergic sensitization takes place. Once sensitized, the repeated allergen exposure will lead to disease persistence. These mechanisms could also be used to explain airway wall remodelling and the susceptibility of the asthmatic lung to exacerbations provoked by respiratory viruses, air pollution episodes and exposure to biologically active allergens. Variable activation of this epithelial-mesenchymal trophic unit could also lead to the emergence of different asthma phenotypes and a more targeted approach to the treatment of these. It also raises the possibility of developing treatments that increase the lung's resistance to the inhaled environment rather than concentrating all efforts on trying to suppress inflammation once it has become established.<br/
The evolving nature of rights
No full textA Michigan State University faculty panel participates in a discussion entitled, "The Evolving Nature of Rights." Panelists describe their research, perspectives and conclusions around the evolving nature of civil and human rights including indigenous property rights, the right to water, privacy, health care and more. Panelists are: Associate Dean Steven Kautz, College of Social Science; Dean Joan Howarth, College of Law; Associate Chair Laurie Medina, Department of Anthropology, College of Social Science; Chair of Water Research Joan Rose, Department of Fisheries and Wildlife, College of Agriculture and Natural Resources; and Dean William Strampel, College of Osteopathic Medicine. Dr. Cynthia Jackson-Elmoore, Dean of the Honors College, convenes the session and moderates questions from the audience. Part of the series "Sharper Focus/Wider Lens" sponsored by: MSU Honors College; College of Law; College of Social Science; Department of Fisheries and Wildlife; College of Agriculture and Natural Resources; and the College of Osteopathic Medicine. Held in the MSU Student Union
Seasonal variability of projected future climate and its impact on the freshwater discharge to the Hudson River and water residence time of the Hudson estuary
No full textThis report was prepared for the New York State Water Resources Institute (WRI) and the Hudson River Estuary program of the New York State Department of Environmental Conservation, with support from the NYS Environmental Protection FundClimatic sensitivity of an estuary to the nutrient pollution is highly affected by water residence time, which in turn is dependent upon the magnitude of freshwater inflows to the estuary. For example, the Hudson River/NYC Harbor Estuary has not suffered from toxic algal blooms as much as other estuaries even though it is the most heavily nutrient-loaded estuary in North America (Howarth et al., 2006). This insensitivity of the estuary to the high level of nutrient pollution is largely attributed to its short water residence time), flushing phytoplankton out before they fully grow into harmful algal blooms. Consideration of seasonal variation is highly relevant here, because the residence time of water in the lower Hudson estuary may increase significantly during the summer due to reduced freshwater discharge of the Hudson River. In addition, the light limitation from turbidity is likely to diminish during the summertime periods, facilitating phytoplankton production (Howarth et al., 2000, 2006, 2011)
Designing a visible city for visually impaired users
No full textThis paper reports on an ongoing doctoral research project which aims to identify the main barriers to access within the built environment for persons with a visual impairment. The research seeks to investigate whether these barriers are common for all types of visual impairment and degree of vision loss and if so, what inclusive design solutions can accommodate the needs of the majority of visually impaired users. An access audit has been conducted within Glasgow city centre which sought to quantify the number and type of hazards present within a typical built environment. This was followed up by a questionnaire which asked participants to rate factors which may prevent them from making independent visits to their nearest city centre including psychological factors, physical features and obstructions resulting from the presence of street furniture. Participants also indicated the colours and contrasts which they find easiest to detect within the built environment. These findings will be used to inform the creation of a new set of design guidelines to assist designers, architects and urban planners as to how they can provide more accessible and inclusive environments for the visually impaired population
The roles of eosinophils and interleukin-5 in the pathophysiology of chronic rhinosinusitis with nasal polyps
No full textChronic rhinosinusitis with nasal polyps (CRSwNP) is generally associated with eosinophilic tissue infiltration linked to type 2 inflammation and characterized by elevated levels of interleukin (IL)-5 and other type 2 inflammatory mediators. Although distinct and overlapping contributions of eosinophils and IL-5 to CRSwNP pathology are still being explored, they are both known to play an important role in NP inflammation. Eosinophils secrete numerous type 2 inflammatory mediators including granule proteins, enzymes, cytokines, chemokines, growth factors, lipids, and oxidative products. IL-5 is critical for the differentiation, migration, activation, and survival of eosinophils but is also implicated in the biological functions of mast cells, basophils, innate lymphoid cells, B cells, and epithelial cells. Results from clinical trials of therapeutics that target type 2 inflammatory mediators (including but not limited to anti-IL-5, anti-immunoglobulin-E, and anti-IL-4/13) may provide further evidence of how eosinophils and IL-5 contribute to CRSwNP. Finally, the association between eosinophilia/elevated IL-5 and greater rates of NP recurrence after endoscopic sinus surgery (ESS) suggests that these mediators may have utility as biomarkers of NP recurrence in diagnosing and assessing the severity of CRSwNP. This review provides an overview of eosinophil and IL-5 biology and explores the literature regarding the role of these mediators in CRSwNP pathogenesis and NP recurrence following ESS. Based on current published evidence, we suggest that although eosinophils play a key role in CRSwNP pathophysiology, IL-5, a cytokine that activates these cells, also represents a pertinent and effective treatment target in patients with CRSwNP.</p
Variation in sediment and seagrass characteristics reflect multiple stressors along a nitrogen-enrichment gradient in a New England lagoon
No full text© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Haviland, K. A., Howarth, R. W., Marino, R., & Hayn, M. Variation in sediment and seagrass characteristics reflect multiple stressors along a nitrogen-enrichment gradient in a New England lagoon. Limnology and Oceanography, 67, (2022): 660-667, https://doi.org/10.1002/lno.12025.We examined concentrations of organic carbon, dissolved sulfides, total sediment sulfur, and stable sulfur isotope ratios in seagrass leaf tissues across a nitrogen-enrichment gradient in a coastal marine ecosystem (Cape Cod, Massachusetts) in 2007–2010 and 2017–2019. We also measured seagrass aboveground and belowground biomass, epibiota biomass, and leaf chlorophyll content. Seagrasses were present at all sites in the former period but were lost at our most nitrogen-impacted site (Snug Harbor) by 2011. In 2007–2010, sediment organic carbon and dissolved sulfides were highest in Snug Harbor and decreased along the gradient; leaf tissues depleted in 34S also indicated higher sulfide intrusion into seagrass tissues in more eutrophic areas. By 2017–2019, sediment organic carbon and pore-water soluble sulfides had decreased in Snug Harbor, but had increased at the intermediate site, to levels found at the most impacted site prior to the seagrass die-off. Again, leaf tissue 34S depletion reflected this pattern, indicating seagrasses were exposed to the highest sulfides at the intermediate site. The decreases in sediment organic carbon and soluble sulfides in Snug Harbor years after the loss of the seagrasses illustrate a feedback between high organic matter in seagrass beds and increasing stressors like elevated soluble sulfides in nutrient-enriched systems. We found significant relationships between sediment conditions and seagrass responses, including greater aboveground to belowground biomass ratios, epibiota biomass, and 34S-depleted leaves at sites with high pore-water sulfide and highly organic sediments. Our research suggests that the reduction of anthropogenic nitrogen entering the harbor is necessary for improving sediment quality and preventing seagrass mortality.The authors thankfully acknowledge as our funding sources: The National Science Foundation Biocomplexity, GRFP, and LTREB programs (grants 0420575, 1654845, and 2018241438), and the Woods Hole SeaGrant program
Epigenetic mechanisms silence a disintegrin and metalloprotease 33 expression in bronchial epithelial cells
No full textBackground: A disintegrin and metalloprotease 33 (ADAM33) polymorphism is strongly associated with asthma and bronchial hyperresponsiveness.Although considered to be a mesenchymal cell–specific gene, recent reports have suggested epithelial expression of ADAM33 in patients with severe asthma.Objectives: Because dysregulated expression of ADAM33 can contribute to disease pathogenesis, we characterized the mechanism or mechanisms that control its transcription and investigated ADAM33 expression in bronchial biopsy specimens and brushings from healthy and asthmatic subjects.Methods: The ADAM33 promoter and CpG island methylation were analyzed by using bioinformatics, luciferase reporters, and bisulfite sequencing of genomic DNA. Epithelial-mesenchymal transition was induced by using TGF-b1. ADAM33 mRNA was scrutinized in bronchial biopsy specimens and brushings by using reverse transcriptase–quantitative polymerase chain reaction, melt-curve analysis, and direct sequencing.Results: The predicted ADAM33 promoter (2550 to 187) had promoter transcriptional activity. Bisulfite sequencing showed that the predicted promoter CpG island (2362 to 180) was hypermethylated in epithelial cells but hypomethylated in ADAM33-expressing fibroblasts.Treatment of epithelial cells with 5-aza-deoxycytidine caused demethylation of the CpG island and induced ADAM33 expression. In contrast, phenotypic transformation of epithelial cells through a TGF-b–induced epithelial mesenchymal transition was insufficient to induce ADAM33 expression. ADAM33 mRNA was confirmed in bronchial biopsy specimens, but no validated signal was detected in bronchial brushings from healthy or asthmatic subjects.Conclusion: The ADAM33 gene contains a regulatory CpG island within its promoter, the methylation status of which tightly controls its expression in a cell type–specific manner. ADAM33 repression is a stable feature of airway epithelial cells, irrespective of disease. (J Allergy Clin Immunol 2008;121:1393-9.
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