Bakgrund: Inom vården förekommer det ofta smärtsamma procedurer i form av behandlingar och undersökningar. Dessa procedurer kan vara obehagliga för barn vilket gör smärtlindring till en viktig del av pediatrisk vård. Lustgas är ett bra alternativ till barn på grund av att den har lugnande effekt, inte kräver någon ytterligare smärtsam procedur som nålstick och har snabb och kortvarig effekt. Lustgasens lämplighet inom pediatrisk vård kan motivera en ökad användning. Syfte: Det huvudsakliga syftet var att undersöka vad sjuksköterskor på Akademiska barnsjukhuset med utbildning i lustgasadministrering ser för möjligheter och hinder i att administrera lustgas till barn (0-18 år) vid smärtsamma procedurer. Ett andra syfte var att undersöka hur dessa uppfattningar skiljer sig mellan avdelningar samt i förhållande till erfarenhet och utbildning. Metod: Studiens design var kvantitativ metod med en enkät-tvärsnittsstudie bestående av 25 frågor. Enkäten besvarades av samtliga 24 tillfrågade sjuksköterskor på Akademiska barnsjukhuset med utbildning i lustgasadministrering. Resultat: Sjuksköterskorna som deltog i studien ansåg att lustgasadministrering är en bra smärtlindringsmetod vid de flesta smärtsamma procedurer och de ansåg att de hade goda förutsättningar att administrera lustgas. Sjuksköterskorna föreslår lustgas generellt cirka 3-4 gånger per månad och de sjuksköterskor med längre erfarenhet ser fler tillfällen till lustgas och föreslår det oftare som smärtlindringsmetod. De uppfattade låg ålder som ett hinder då de ansåg att små barn har svårt att samarbeta vid lustgasadministrering. Slutsats: Sjuksköterskorna upplever i stort att de har goda möjligheter att administrera lustgas till barn vid smärtsamma procedurer och att de har fått tillräcklig utbildning i ämnet. Sjuksköterskors inställning till lustgas är övervägande positiv och de anser att lustgas är lämpligt till barn över fyra år. / Background: In healthcare, treatments and examinations can often include some level of pain. For children, such painful procedures can be difficult to understand and accept, making pain management a key part of pediatric care. Nitrous oxide is a good option for children since it is inhaled and its effect is transient and rapid. Nurses trained in administration of nitrous oxide to children can safely administer it, allowing for a wider use. The suitability of nitrous oxide in pediatric care can justify an increased usage. Aim: The main purpose was to investigate how nurses at Akademiska Children's Hospital with training in nitrous oxide administration view their possibilities and obstacles in administering nitrous oxide in children (0-18 years) during painful procedures. A second objective was to investigate how these perceptions differ between departments and in relation to experience and training. Method: The study design was a quantitative method with a questionnaire-sectional study consisting of 25 questions. The questionnaire was answered by 24 nurses at Akademiska Children's Hospital with training in nitrous oxide administration. Main results: Nurses at Akademiska Children's Hospital consider nitrous oxide to be a good method of pain relief for most painful procedures and that they had good opportunities to administer nitrous oxide. The nurses suggested nitrous oxide on average about three to four times per month and the nurses with long experience saw more opportunities for nitrous oxide and suggested it more often. Conslusion: The nurses generally felt that they have good opportunities to administer nitrous oxide to children during painful procedures and that they have received adequate training for the task. The nurses have a predominantly positive attitude towards nitrous oxide and they consider nitrous oxide to be suitable for children over four years of age.

Knowing the control of landscape position in greenhouse gas (GHG) emission from the Prairie pothole region is necessary to provide reliable emission estimates needed to formulate strategies for reducing emission from the region. Presented here are results of a study investigating the control of landscape position on the flux of nitrous oxide (N2O) and methane (CH4) from an agricultural soil. Field flux of N2O and CH4 and associated soil parameters from the Upper, Middle, Lower and Riparian slope positions were monitored from spring to fall of 2005, and spring of 2006, at the Manitoba Zero-Tillage Research Association (MTRZA) farm, 17.6km North of Brandon, MB. The field site consisted of a transect of 128 chambers segmented into the four landscape positions, with either all chambers or a subset of the chambers (32) sampled on select days. Spring thaw is an important period for annual inventory of N2O emission, thus, soil samples were also collected from the four slope positions in fall 2005, and treated in the laboratory to examine how antecedent moisture and landscape position affect the freeze-thaw emission of N2O from soil. Daily emissions of N2O and CH4 for 2005 were generally higher than for 2006, the former being a wetter year. There was high temporal variability in N2O and CH4 emission, with high fluxes associated with events like spring thaw and fertilizer application in the case of N2O, and rapid changes in soil moisture and temperature in the case of CH4. There was a high occurrence of hotspots for N2O emission at the Lower slope, associated with its high soil water-filled porosity (WFP) and carbon (C) availability. The Riparian zone was not a source of N2O emission, despite its soil WFP and organic C being comparable with the Lower slope. The hotspot for CH4 emission was located at the Riparian zone, associated with its high soil WFP and C availability. The Upper and Middle slope positions gave low emission or consumed CH4, associated with having low soil WFP and available C. This pattern in N2O and CH4 emission over the landscape was consistent with examination of entire 128 chambers on the transect or the 32 subset chambers. Significantly lowering the antecedent moisture content of soil by drying eliminated the freeze-thaw emission of N2O, despite the addition of nitrate to the soil. This was linked to drying slightly reducing the denitrifying enzyme activity (DEA) of soil. The highest and earliest freeze-thaw emission of N2O was from the Riparian zone, associated with its high antecedent moisture content, DEA and total organic C content. The addition of nitrate to soil before freezing failed to enhance freeze-thaw emission of N2O from the Upper, Middle and Lower slope positions, but increased emission three-fold for the Riparian zone. Despite the greater potential of the Riparian zone to produce N2O at thaw compared to the Upland slopes, there was no spring-thaw emission of N2O from the zone on the field. This was because this zone did not freeze over the winter, due to insulation by high and persistent snow cover, vegetation and saturated condition. The denitrifying potential and freeze-thaw N2O emission increased in going from the Upper to the Lower slope position, similar to the pattern of N2O emission observed on the field. The localization of hotspots for N2O and CH4 emission within the landscape was therefore found to be driven by soil moisture and C availability. When estimating GHG emission from soil, higher emission index for N2O and CH4 should be given to poorly-drained cropped and vegetated areas of the landscape, respectively. The high potential of the Riparian zone for spring-thaw emission of N2O should not be discountenanced when conducting annual inventory of N2O emission at the landscape scale. When fall soil moisture is high, snow cover is low, and winter temperature is very cold, freeze-thaw emission of N2O at the Riparian zones of the Prairie pothole region may be very high.

Over recent decades, environmental regulations on wastewater treatment plants (WWTP) have trended towards increasingly stringent nutrient removal requirements for the protection of local waterways. However, such regulations ignore the other environmental impacts that might accompany the apparent improvements to the WWTP. This PhD thesis used Life Cycle Assessment (LCA) to quantify these environmental trade-offs, and so better inform policy makers on the wider benefits and burdens associated with wastewater treatment. A particular focus was also given to the generation of methane and nitrous oxide in wastewater systems, since the quantification of greenhouse gas (GHG) emissions from WWTPs is presently a substantial area of uncertainty. Rapid changes to the GHG regulatory landscape mean that this level of uncertainty, now represents an unacceptable business risk for many water utilities. Specifically, there were three research objectives of this thesis: Research Objective No.1 – Environmental optimisation of wastewater treatment systems – For typical receiving environments, the optimum wastewater treatment system configuration is not necessarily at the limit of best practice for nutrient removal. The LCA approach to this research objective was divided into two stages. In stage I, a comprehensive desk-top life cycle inventory of ten different wastewater treatment scenarios was completed. The scenarios covered six process configurations and treatment standards ranging from raw sewage to advanced nutrient removal. It was shown that physical infrastructure, chemical usage and operational energy all increased with the level of nutrient removal. These trends represented a trade-off of negative environmental impacts against improved local receiving water quality. In stage II of the LCA, a quantitative life cycle impact assessment of the ten scenarios, referenced against Australian normalisation data, was completed. From a normalised perspective against Australian society, the contribution of WWTPs to headline issues such as global warming and energy consumption was found to be very small. The more prominent environmental impact categories were eutrophication due to nutrient discharge and toxicity issues, due to heavy metals in biosolids. There existed a broader environmental trade-off for nutrient removal, that could only be justified by society and regulators implicitly placing higher value on local water quality, than on other global environmental pressures. In light of this quantitative LCA, regulatory agencies should consider the broader environmental consequences of their policies such as the Queensland Water Quality Guidelines. It is suggested that the scope of WWTP licensing considerations should be widened from a singular focus on water quality objectives, to a more comprehensive LCA-based approach. Research Objective No. 2 – Quantification of nitrous oxide emissions from biological nutrient removal (BNR) wastewater treatment plants – Current GHG assessment methods for wastewater treatment plants are grossly inaccurate because of significant unaccounted N2O emissions. The research for objectives two and three was funded by the Water Services Association of Australia (WSAA), which is the peak body of the Australian urban water industry. Thus, whilst the earlier LCA results suggested that GHG emissions from WWTPs were insignificant from a national perspective, the industry is actually very engaged on this issue from an environmental responsibility and business risk perspective. This PhD study adopted a rigorous mass balance approach to determine N2O-N generation at seven full-scale WWTPs. The results varied considerably in the range 0.006 – 0.253 kgN2O-N generated per kgNdenitrified (average: 0.035 +/- 0.027). These results were generally larger than the current default value assumed in the National Greenhouse and Energy Reporting (Measurement) Technical Guidelines (i.e. 0.01 kg N2O-N.kgN-1denitrified). High N2O-N generation was shown to correspond with elevated bulk NO2--N concentrations in the bioreactor. The results also suggested that WWTPs designed for low effluent TN have lower and less variable N2O generation than plants that only achieve partial denitrification. Research Objective No.3 – Quantification of methane emissions from low-strength wastewater collection systems – Current default GHG assessment methods for sewerage systems are grossly inaccurate because of significant unaccounted CH4 emissions from rising mains. Presently, international GHG guidelines state that “wastewater in closed underground sewers is not believed to be a significant source of methane” (IPCC, 2006). However, the results of this PhD research demonstrated that methane generation in rising main sewers is substantial. It was shown that dissolved methane concentrations were dependent upon pipeline geometry and sewage residence time. Consequently, it was possible to develop a simple, yet robust, theoretical model that predicted methane generation from these two independent parameters. This model provides a practical means for water authorities globally to make an estimate of the currently unaccounted methane emissions from pressurised sewerage systems.

Over recent decades, environmental regulations on wastewater treatment plants (WWTP) have trended towards increasingly stringent nutrient removal requirements for the protection of local waterways. However, such regulations ignore the other environmental impacts that might accompany the apparent improvements to the WWTP. This PhD thesis used Life Cycle Assessment (LCA) to quantify these environmental trade-offs, and so better inform policy makers on the wider benefits and burdens associated with wastewater treatment. A particular focus was also given to the generation of methane and nitrous oxide in wastewater systems, since the quantification of greenhouse gas (GHG) emissions from WWTPs is presently a substantial area of uncertainty. Rapid changes to the GHG regulatory landscape mean that this level of uncertainty, now represents an unacceptable business risk for many water utilities. Specifically, there were three research objectives of this thesis: Research Objective No.1 – Environmental optimisation of wastewater treatment systems – For typical receiving environments, the optimum wastewater treatment system configuration is not necessarily at the limit of best practice for nutrient removal. The LCA approach to this research objective was divided into two stages. In stage I, a comprehensive desk-top life cycle inventory of ten different wastewater treatment scenarios was completed. The scenarios covered six process configurations and treatment standards ranging from raw sewage to advanced nutrient removal. It was shown that physical infrastructure, chemical usage and operational energy all increased with the level of nutrient removal. These trends represented a trade-off of negative environmental impacts against improved local receiving water quality. In stage II of the LCA, a quantitative life cycle impact assessment of the ten scenarios, referenced against Australian normalisation data, was completed. From a normalised perspective against Australian society, the contribution of WWTPs to headline issues such as global warming and energy consumption was found to be very small. The more prominent environmental impact categories were eutrophication due to nutrient discharge and toxicity issues, due to heavy metals in biosolids. There existed a broader environmental trade-off for nutrient removal, that could only be justified by society and regulators implicitly placing higher value on local water quality, than on other global environmental pressures. In light of this quantitative LCA, regulatory agencies should consider the broader environmental consequences of their policies such as the Queensland Water Quality Guidelines. It is suggested that the scope of WWTP licensing considerations should be widened from a singular focus on water quality objectives, to a more comprehensive LCA-based approach. Research Objective No. 2 – Quantification of nitrous oxide emissions from biological nutrient removal (BNR) wastewater treatment plants – Current GHG assessment methods for wastewater treatment plants are grossly inaccurate because of significant unaccounted N2O emissions. The research for objectives two and three was funded by the Water Services Association of Australia (WSAA), which is the peak body of the Australian urban water industry. Thus, whilst the earlier LCA results suggested that GHG emissions from WWTPs were insignificant from a national perspective, the industry is actually very engaged on this issue from an environmental responsibility and business risk perspective. This PhD study adopted a rigorous mass balance approach to determine N2O-N generation at seven full-scale WWTPs. The results varied considerably in the range 0.006 – 0.253 kgN2O-N generated per kgNdenitrified (average: 0.035 +/- 0.027). These results were generally larger than the current default value assumed in the National Greenhouse and Energy Reporting (Measurement) Technical Guidelines (i.e. 0.01 kg N2O-N.kgN-1denitrified). High N2O-N generation was shown to correspond with elevated bulk NO2--N concentrations in the bioreactor. The results also suggested that WWTPs designed for low effluent TN have lower and less variable N2O generation than plants that only achieve partial denitrification. Research Objective No.3 – Quantification of methane emissions from low-strength wastewater collection systems – Current default GHG assessment methods for sewerage systems are grossly inaccurate because of significant unaccounted CH4 emissions from rising mains. Presently, international GHG guidelines state that “wastewater in closed underground sewers is not believed to be a significant source of methane” (IPCC, 2006). However, the results of this PhD research demonstrated that methane generation in rising main sewers is substantial. It was shown that dissolved methane concentrations were dependent upon pipeline geometry and sewage residence time. Consequently, it was possible to develop a simple, yet robust, theoretical model that predicted methane generation from these two independent parameters. This model provides a practical means for water authorities globally to make an estimate of the currently unaccounted methane emissions from pressurised sewerage systems.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2006. / Härtill 3 uppsatser.

Thesis (Ph.D.)--York University, 2006. Graduate Programme in Chemistry. / Typescript. Includes bibliographical references. Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:NR19763

Thesis (Ph.D.)--University of Wollongong, 2008. / Typescript. Includes bibliographical references.

Diss. med. dent. Zürich. / Literaturverz.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2008. / Title from title screen (site viewed Jan. 15, 2009). PDF text: 147 p. : col. ill. ; 9 Mb. UMI publication number: AAT 3316416. Includes bibliographical references. Also available in microfilm and microfiche formats.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The soybean (Glycine max) cultivation in rotation with rice (Oryza sativa) in paddy soils is a growing practice in the state of Rio Grande do Sul. However, there is little information on the emission of methane (CH4) and nitrous oxide (N2O) during soybean growing season in lowland and the contribution of biological nitrogen fixation (BNF) for crops in this environment. The study was aimed to evaluate the emissions of CH4 and N2O, BNF and soybean productivity in lowland managed for three years with different systems of soil tillage/straw after the rice harvest. The experiment was conducted during the growing season of 2012/2013 on a Plano soil. The treatments consisted of different systems of soil management/straw applied for three years after the rice harvest: ryegrass (RY), disc harrow (DH), knife-roller (KR), fallow + disc harrow (F + DH), disc harrow + disc harrow (DH + DH), knife-roller + disc harrow (KR + DH), removal of straw (RS) and fallow (F). Besides these, a natural lowland (NL) was used as control. The NL had the lowest N2O emissions; however CH4-C (161 kg ha-1) emissions were higher when compared to soybean cultivated in lowland. The highest N2O emissions occurred from soybean cultivation, being observed in the treatment RY where the highest cumulative emission was 7.9 kg N2O-N ha-1. The management of soil/straw performed with DH, compared to systems with KR and F, caused increased density by up to 10% and reduction in macro-porosity and total porosity in the topsoil. Changes in soil physical properties caused by different soil/straw tillage systems did not result in a decreased N accumulation, BNF contribution (mean 67%) and productivity of soybean. / O cultivo da soja (Glycine Max) em rotação com o arroz (Oryza sativa) em solos de várzea é uma prática crescente no estado do Rio Grande do Sul (RS). No entanto, existem poucas informações sobre a emissão de metano (CH4) e óxido nitroso (N2O) durante o cultivo da soja em várzea e a contribuição da fixação biológica (FBN) para a cultura nesse ambiente. O estudo teve por objetivo avaliar as emissões de CH4 e N2O, a FBN e a produtividade da soja em várzea manejada durante três anos com diferentes sistemas de manejo do solo/palha após a colheita do arroz. O experimento foi conduzido no ano agrícola 2012/2013 em um Planossolo Hidromórfico Eutrófico arênico. Os tratamentos foram compostos por diferentes sistemas de manejo do solo/palha aplicados durante três anos após a colheita do arroz: azevém (AZ), grade (G), rolo-faca (RF), pousio + grade (P+G), grade + grade (G+G), rolo-faca + grade (RF+G), retirada da palha (RP) e pousio (P). Além desses, foi avaliada uma área natural de banhado (AN) que serviu como testemunha. A AN apresentou as menores emissões de N2O, porém elevada emissão de C-CH4 (161 kg ha-1) quando comparada ao cultivo da soja em várzea. As maiores emissões de N2O ocorreram no período de cultivo da soja, sendo observada no tratamento AZ a maior emissão acumulada desse gás (7,9 kg de N-N2O ha-1). O manejo do solo/palha realizado com G, comparado aos sistemas com RF e P, provocam aumento da densidade em até 10% e redução na macroporosidade e porosidade total na camada superficial do solo. As modificações causadas nos atributos físicos do solo pelos diferentes sistemas de manejo do solo/palha, não resultaram em diminuição no acúmulo de N, contribuição da FBN (média de 67%) e produtividade de grãos de soja.