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11	A "Tricky Business" - Knowledge Production in Children's Environmental Health Seto, So Yan 31 August 2011 (has links) Using critical feminist theories and methodologies, my research investigates the power relations and influences at play within the field of children's environmental health. I begin with the research question of how a parent's everyday purchase of a toy or other children's product is "hooked into" extra-local governance (agenda-setting, rule-making and monitoring). Focusing on Bisphenol A and phthalates as an example, in-depth interviews were conducted with six government officials (three federal and three municipal), three non-governmental organization (NGO) representatives, a politician, six higher education faculty members and a parent, as well as two focus groups of 23 parents. Legislation and other relevant documents from governments, NGOs, industry and media were analyzed together with reports of their activities and attitudes to theorize "how things work" in the identification and management of toxic substances in products for sale, with a special interest in how this affects children's environmental health. My research revealed the influence of neo-liberalism, corporate power and over-reliance on strictly evidence-based biomedical reductionism in slowing down assessment and regulation of chemicals while many health professionals and grassroots activists have called for swifter responses based on the precautionary principle, as favoured by European governments. That is, politics and bureaucracy, with the approval of industry, over the past two decades, have clung to reductionist science as the only paradigm for understanding toxicity, thus slowing down regulatory processes. Although the historical and epistemological power relations mapped in my research work together to legitimize scientific certainty rather than the precautionary principle, I argue that the resulting regulatory logjam has been and could be addressed by reference to European examples, knowledge produced by collectives and the establishment of upstream and equity-based public health strategies with public input into the process. Knowledge Production Children's Health and the Enviornment Children's Environmental Health Public Health Legislation Canadian Politics Non-governmental organization health professional education Bisphenol A Phthalates 0680 0630 0350 0766 0573
12	INVESTIGATION OF CORN YIELD IMPROVEMENT FOLLOWING CEREAL RYE USING STARTER NITROGEN FERTILIZER Houston L Miller (7830965) 20 November 2019 (has links) Cereal rye (CR), the most common and effective nitrogen (N) scavenging cover crop option in the Midwest, is often utilized in cropping systems to reduce nitrate loss for environmental benefits. To increase environmental efficiency in Midwest corn cropping systems, we must increase the overall adoption of CR. However, due to the yield reduction potential (6%) for corn planted after CR termination, CR is primarily recommended before soybean. To increase CR adoption, we must develop adaptive fertilizer management practices that achieve competitive grain yields relative to cropping systems where CR is not adopted. Therefore, the objectives of this study are to determine (1) the effect of CR and starter nitrogen rate on corn growth and nitrogen content. (2) the optimum starter nitrogen rate to achieve agronomic optimum corn yield following CR. (3) the impact of phosphorus (P) at starter on plant growth, nitrogen content, and yield with the inclusion of CR. For our study, five starter N rates were applied in a 5x5 cm band to both CR and non-CR plots, concentrations ranged from 0-84 kg N ha<sup>-1 </sup>in 28 kg N ha<sup>-1</sup> intervals. Total N applied was the same for each treatment, relative to its location, and was split between starter N at planting and sidedress applied at growth stage V6 relatively. Although CR termination took place at least two weeks before planting, CR decreased corn grain yield at one of three locations by an average of 8%, nitrogen recovery efficiency (NRE) by 27%, and R6 total N content by 23%, relative to the conventional control (non-CR 0N), when no starter N was applied. At one of three locations, starter N rates of 56 kg N ha<sup>-1</sup>, 56 kg N ha<sup>-1 </sup>plus 17 kg P ha<sup>-1</sup>, and 84 kg N ha<sup>-1</sup> increased corn grain yield, in CR plots, and 56 kg N ha<sup>-1</sup> plus 17 kg P ha<sup>-1</sup> increased corn grain yield in non-CR plots. Phosphorus increased corn grain N content at growth stage R6 in one of three locations and did not impact corn grain yield at all locations. We conclude that the inclusion of starter N at planting has the potential to increase agronomic productivity in CR corn cropping systems in soil environments with a high capacity to mineralize soil N. However, further research is required to refine our starter N results to find an optimum starter N rate to apply before planting corn following CR. Agronomy cereal rye corn starter nitrogen cover crop soil inorganic nitrogen biomass nitrogen content carbon content conservation cereal rye disease cereal rye impact on corn grain yield phosphorus corn 5x5 band 2x2 band sidedress UAN corn yield rye rye growth corn growth stage corn development nitrogen uptake corn biomass grain moisture stalk nitrate contrasts corn population cereal rye biomass nitrate reduction corn following cereal rye starter urea ammonium nitrate nutrient reduction strategy no-till no till nitrogen reduction management practices spring soil enviornment

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A "Tricky Business" - Knowledge Production in Children's Environmental Health

INVESTIGATION OF CORN YIELD IMPROVEMENT FOLLOWING CEREAL RYE USING STARTER NITROGEN FERTILIZER