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OPENING UP THE BOX: EXPLORING THE SCALING OUT OF THE GOOD FOOD BOX ACROSS CANADALaporte Potts, Stephanie Lentz 07 February 2014 (has links)
The Good Food Box (GFB) program holds a great deal of promise to expand our understanding of Community Food Security (CFS). CFS represents a vision for solving hunger and other problems with the food system through an integrated approach that improves access to good and appropriate food for all while at the same time building community, strengthening local agricultural economies, and maximizing social justice. The GFB, one type of CFS program, is a community-based initiative found across Canada that provides a box of healthy food to customers at near wholesale prices; it has the potential to increase access to healthy food, develop alternative distribution channels, link producers more closely with consumers, build community connections, and more. Yet despite the fact that over 50 unique GFB programs exist across Canada, little research has been done on how these myriad programs are structured and function, how this program model has spread to and been adapted by communities across Canada, and how individual programs operate while balancing multiple goals and priorities.
This paper, based on qualitative interviews with managers at 21 GFB programs across Canada, explores the diversity of GFB programs in Canada, and how these programs balance multiple priorities along with day-to-day logistical constraints. GFB programs functioning across Canada have diverse goals, tensions sometimes arise when balancing multiple goals, and programs have found various ways to resolve these tensions. Moreover, GFB programs are educating and empowering people in their communities, as well as networking and learning among themselves. This is one of the first studies describing the breadth of GFB programs across Canada, and some of the findings have not been identified in previous scholarship. I describe the variety of program structures, the main priorities and goals that the programs identify, and some of the tensions and innovations that arise when working to balance the multiple goals and dimensions of CFS. I also discuss how programs communicate and learn from each other, and how the GFB in Canada can help us understand the CFS movement more generally.
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Use and Effectiveness of Wildlife Crossing Structures with Short Sections of Wildlife FencingFairbank, Elizabeth Rose 07 February 2014 (has links)
Our growing transportation infrastructure in the United States has many direct and indirect impacts to wildlife populations. Humans are also impacted by the interaction of roads and wildlife in terms of wildlife-vehicle collisions (WVCs); which annually result in: hundreds of human fatalities, tens of thousands of human injuries, and billions of dollars in property damage. In response to concerns for wildlife and human safety, road mitigation measures are becoming an increasingly important tool for transportation agencies to minimize the risks of WVCs. The construction of multiple wildlife crossing structures in combination with wildlife fencing have been shown to reduce WVCs by over 80% where extensive continuous wildlife fencing (covering many miles) has been implemented, and by 50-60% in areas where more limited fencing (covering 1-3 miles) has been implemented. In areas where land use is dominated by humans (agriculture, housing, access roads, etc.) such mitigation measures are not always possible or desirable. This results in a push towards more isolated crossing structures with little to no wildlife fencing to provide frequent road access and preserve landscape aesthetics. The effectiveness of isolated crossing structures with short sections of fencing (only a few hundred meters or less) is not well documented in terms of potential WVC reduction or wildlife use of the structures. In this study I investigate: the use of isolated crossing structures and fence ends by target species, the effect of fence length on at-grade crossings, and the ability of short sections of fencing to keep wildlife off the road. Overall, 82% of wildlife used the crossing structures for crossing as opposed to going around fence ends. Over the length of fence lengths sampled (3m-256m) there was no relationship between fence length and the number of crossings at fence ends. Deer were often foraging at fence ends, with nearly half of all foraging events occurring in the right of way (closer to the road than the fence is/would be). Overall, deer generally choose to use the crossing structures to get to the other side of the road, but they will still often be present in the right of way where they are not excluded with fencing. This indicates that while isolated crossing structures with short fencing may provide wildlife safe access to habitat on either side of the road, they may not provide the desired reduction in WVCs.
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Native Trout Restoration in the National Parks of the Northern Rockies: An Analysis of Management Actions & OutcomesCanetta, Michael John 07 February 2014 (has links)
The status of native fisheries restoration across the National Park Service (NPS) is a generally undocumented topic, in part due to the recentness of these efforts. This paper explores what the NPS is doing to restore native trout, measure the efficacy of such restoration efforts, identifies factors influencing success, and make recommendations to help the agency improve fishery restoration. Efforts to restore native salmonid species including bull trout (Salvelinus confluentus), Snake River fine-spotted cutthroat trout (Oncorhynchus clarkii behnkei), westslope cutthroat trout (Oncorhynchus clarkii lewisi), and Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) in Glacier National Park (GLAC), Grand Teton National Park (GRTE), and Yellowstone National Park (YELL) were analyzed. While measurable outcomes were hard to identify and success seemingly limited, this analysis highlights that YELL has carried out a disproportionately higher volume of restoration projects and has created more measurable benefits for native trout than the other parks. YELLs Native Fish Conservation Plan, an overarching policy that guides fishery management and sets goals for restoration, seems to be the driving force behind this success. Factors such as long-term funding, staffing, jurisdiction, and partnerships also appear to have a large influence over both the quantity and quality of restoration efforts in these parks. The NPS should mandate fishery restoration in agency-wide policy, conduct large-scale fishery surveys and research, make restoration efforts more integrated and holistic, secure long-term sources of funding, and carry out its mandate without hesitation in order to ensure a healthy future for native trout in the parks.
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Novel approaches towards conversion of organics in supercritical waterSobhy Ramadan, Amr Mohamed January 2008 (has links)
Novel experimental systems and approaches were applied to study and analyze the conversion of selected organics in supercritical water (SCW). High-pressure methanol-air flames were generated in a new and original Visual Flame Cell (VFC) designed and constructed using common commercially-available components. Original SCW flame images, collected using a near-Infrared (NIR) camera, were used to analyze flame ignition, flame characteristics, and flame extinction. New data were also obtained on soot formation and generation of nitrogen oxides (NOx) during the combustion of naphthalene in SCW. The micro-scale hydrothermal diamond anvil cell (DAC) and Raman microscopy were combined in a novel approach for the in-situ monitoring and analysis of SCW processes involving naphthalene and decachlorobiphenyl (10-CB). A NIR (785nm) Raman excitation source (laser) provided the needed middle ground between a strong fluorescence background from organic species irradiated by lasers in the visible range and the water peak interference experienced with infrared (IR) sources. Data collected with the DAC-Raman system were used to identify phase and chemical changes in the SCW-organic system. Original results indicating the degradation of 10-CB in the presence of methanol were obtained. Tubular batch reactors (TBRs) were used to reproduce the DAC-Raman experiments with 10-CB under practical pressures and precise concentrations for obtaining larger reaction product volumes for quantitative analyses. New results showed that the presence of 25% methanol by volume leads to over 56% reduction in oxygen demand for total conversion of 10-CB in faster, cleaner, less corrosive, and lower temperature conditions. This work is an integration of information from three separate experimental systems for practical understanding of SCW as a potential tool for environmental remediation. / Des nouveaux approches et systèmes expérimentaux ont été appliqués pour étudier et analyser la conversion de certains produits organiques choisis dans l'eau supercritique (SCW). Des flammes à haute pression d'air-méthanol ont été produites dans une cellule originale à flamme visible (VFC) construite pour la première fois par des composants disponibles sur le marché. Des images originales de flamme dans l'eau supercritique SCW, prises par un appareil-photo (NIR) à proche-Infrarouge, ont été utilisées pour analyser l'allumage, les caractéristiques, et l'extinction de la flamme. Des nouvelles données ont été également rapportées sur la formation de suie à partir de la combustion du naphtalène et la génération des oxydes d'azote (NOx) dans l'eau SCW. La cellule hydrothermique d'enclume de diamant à micro-échelle (DAC) et la microscopie Raman ont été combinées dans une nouvelle approche pour l'observation in-situ et l'analyse des processus de SCW du naphtalène et du decachlorobiphenyl (10-CB). Une source d'excitation Raman (laser) de NIR (785nm) a fourni une position de compromis adéquate dans les spectres Raman obtenus entre la forte fluorescence des matières organiques lorsqu'elles sont irradiées par rayonnements laser visible et l'interférence de la bande large d'eau avec les rayonnements infrarouge. La donnée obtenue à partir du système DAC-Raman a été utilisée pour identifier la phase et les changements chimiques dans le système organique-SCW. Des résultats originaux indiquant la dégradation de 10-CB en présence de méthanol ont été obtenus. Des réacteurs tubulaires en lots (TBRs) ont été utilisés pour reproduire des expériences DAC-Raman sur la 10-CB sous des pressions pratiques et avec des concentrations précises pour obtenir des quantités suffisantes aux analyses quantitatives. Des nouveaux résultats ont montrés que la présence de 25% en méthanol par volume permet la réduction de plus de 56% en oxyg
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Study of heavy metal accumulation mechanisms in the Lachine Canal sedimentsGalvez de Cloutier, Rosa January 1995 (has links)
Due to industrialization over the past 100 years, the sediments at the bottom of the Lachine Canal and Bay have become contaminated. This study investigated the heavy metal accumulation mechanisms within the Lachine Canal sediments and was carried out in three phases. Laboratory analytical and instrumental work were included. / During Phase I, 28 parameters were measured on 44 samples collected along the Lachine Canal and Bay. The results revealed the presence of a wide variety of both organic and inorganic contaminants. Heavy metals such as Zn $>$ Pb $>$ Cr $>$ Ni $>$ Cu $>$ Cu (in order of decreasing abundance) in addition to organic contaminants (PAH $>$ MAH $>$ PCBs) were found in high concentrations exceeding background concentrations and various quality criteria levels. The total load of both organic and inorganic contaminants was found to be higher in the canal than in the bay zone. Although a positive correlation existed in between % mineral clay fraction or TOC and the total cumulative load of heavy metals, the correlation could not be assessed as conclusive. / Further study on the association heavy metal-sediment constituents (Phase II and III) was carried on the canal zone. X-ray diffraction, Transmission Electron Microscopy and other geochemical analysis revealed that the sediments consisted mainly of silt and clay size fractions composed of: illite, kaolinite and chlorite, calcite and dolomite and minor amounts of Fe- minerals, organic matter and amorphous metal oxides. Each of these constituents bound heavy metals at varying degrees as assessed by a sequential extraction (SE) protocol. The partition distribution pattern was ruled by the geochemical setting. The associations with each phase were (in order of decreasing significance): (1) residual phase Pb (50%) = Cd (50%) $>$ Cr (49%) $>$ Zn (20%), (2) oxide phase Zn (33%) $>$ Pb (32%) $>$ Cr (28%) $>$ Cd (10%), (3) carbonate phase Zn (38%) $>$ Cd (26%) $>$ Pb (13%) $>$ Cr (5%), (4) the organic phase Cr (14%) $>$ Zn (8%) $>$ Cd (6%) $>$ Pb (5%) and (5) the exchangeable phase Cd (8%) $>$ Cr (4%) $>$ Zn (1%) = Pb (1%). The order of abundance in terms of total concentration was 1300 mg Zn/kg, 500 mg Pb/kg, 90 mg Cr/kg and 10 mg Cd/kg. / According to the cation exchange capacity (CEC), carbonate and oxide content measurements, the heavy-metals occupied a minor fraction of the total capacity to retain metals by these mechanisms. The SE results revealed that the partition patterns varied with pH. The phases associated to the carbonate and the exchangeable phases were the most sensitive to a change in pH with the residual phase being almost unchanged. The Zn and Cd were sensitive to release when the conditions drifted to acidic conditions. Towards basic conditions no change in the metal distribution was observed. / The partition patterns for various grain size fractions (${}175 mu$m) revealed that no particular fraction accumulated a certain heavy metal. However, a small increment of heavy metal content with decreasing grain size was found for Zn, Pb and Cd while the contrary was found for Cr. The metal distribution of each grain size fraction followed the pattern under unsieved conditions. / Additionally, it was found that the geotechnical behaviour of sediments was influenced by the chemical composition of the sediments specially with respect to water retention.
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Development of an annular reactor to investigate fouling in UV disinfection systemsGray, Sandy-Kae A. January 2001 (has links)
An annular photo-reactor was designed to investigate precursors and mechanisms thought to promote the fouling of ultra-violet lamps in wastewater disinfection systems. Parameters investigated included temperature of the fouling surface (quartz sleeve) and average fluence applied to the wastewater under irradiation. The reactor was designed to independently control and monitor variations of these parameters. For experimentation, these parameters were manipulated individually and in various combinations to be able to separate those factor(s) that could affect the fouling potential of the system. / The compact and mobile unit utilized a standard low-pressure mercury UV lamp surrounded by two concentric sleeves. The annulus immediately surrounding the lamp was used to control temperature (10--50°C) and fluence (10--100 mJ/cm2 using a chemical transmission filter) emitted by the lamp. The outer annulus was used for the passage and irradiation of wastewater flowing at 10--12 L/min (Re ≅ 1,000). A quartz sleeve separated these annuli. / Hydraulic and heat transfer properties of the unit were fully characterized, and the stability of system operations was confirmed. Optimal lamp UV output approached 3 mW/cm2 and maximum skin temperatures were 45°C. A cupric sulfate solution (0--2 g/L) in distilled water was determined to be the most stable transmission filter. Application of temperature and fluence control revealed that both parameters influenced the disinfection potential of the unit (achieving 1--4 log reduction of fecal coliforms). Collimated beam tests and Point Source Summation computations were used to model fluence distributions within the reactor.
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Measuring Social Vulnerability to Environmental Hazards in the Dutch Province of ZeelandKirby, Ryan Hamilton 12 May 2015 (has links)
The Netherlands is a kingdom known for resisting the perils of natural disaster and keeping records of how these great feats were accomplished. The Dutch have measured physical risk through methods such as the intricate VNK models to predict flood scenarios, but little research has been conducted to examine how the people living in affected areas could be impacted from a natural disaster event. This study employs fine-scale data to construct a social vulnerability index for the 164 districts of the low-lying delta province of Zeeland. The methodology used to measure social vulnerability is built on recent social vulnerability and resilience research that has been conducted in North America, Asia, and Europe. Specific attention is paid to methods used previously and how they can be improved from a statistical standpoint. Factor Analysis of 35 variables selected from the resilience and social vulnerability literature results in nine factors explaining about 72% of the total variance. The factors of vulnerability in Zeeland include Density of the Built Environment and Public Support, Reduced Wealth and Single Households, Infrastructure Accessibility and Career Qualifications, Recovery Capacity and Female Gender, Personal Wealth, Occupation, Residential Quality, Access to Healthcare, and Evacuation Potential. The index is constructed using data for all 35 variables with weight decided by the variance explained by each factor. Relative index scores range from a low social vulnerability score of 0.248 in the district Kattendijk, Goes, to the highest social vulnerability score of 0.458 found in Oudelandse Hoeve, Ternuezen. The highest-scoring districts are located towards the South of Zeeland. Eight of the ten most vulnerable districts located in Terneuzen. The Municipality of Goes contains more low-scoring districts than any other municipality. The majority of low scoring, less vulnerable districts are located on the Central lobe of Zeeland. The results of the social vulnerability analysis provide new insights for policy makers, researchers, and community stakeholders that could be combined with Dutch flood-scenario models to guide planning efforts in the Netherlands to mitigate the damaging impacts of future floods. The study provides an example for adaptation of a social vulnerability index for a fine level of analysis.
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Three Essays on Air Pollution in Developing CountriesTan-Soo, Jie-Sheng January 2015 (has links)
<p>Air pollution is now recognized as the deadliest problem in developing countries and policymakers are pressed to take action to relieve its health burden. Using a variety of econometric strategies, I explore various issues surrounding policies to manage air pollution in developing countries. In the first chapter, using locational equilibrium logic and forest fires as instrument, I estimated the willingness-to-pay for improved PM2.5 in Indonesia. I find that WTP is at around 1% of annual income. Moreover, this approach allows me to compute the welfare effects of a policy that reduces forest fires by 50% in some provinces. The second chapter continues on this theme by assessing the long-term impacts the early-life exposure to air pollution. Using the 1997 forest fires in Indonesia as an exogenous shock, I find that prenatal exposure to air pollution is associated with shorter height, decreased lung capacity, and lower results in cognitive tests. These findings are consistent across several specifications and robustness checks. The last chapter tackles the issue of indoor air pollution in India. In here, I use stated responses from a discrete choice experiment to categorize households into three distinct groups of cookstoves preferences; interested in improved cookstoves, interested in electric cookstoves; uninterested. These groupings are then verified using actual stoves purchase decisions and I found large area of agreement between households stated responses and their purchase decisions.</p> / Dissertation
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Application of zircon to magmatic investigations: I. Exploring effects of magmatic-tectonic interplay on silicic magma genesis in Iceland; II. Elucidating copper mineralization trends in a Mid-Jurassic magmatic system, Yerington, NV, USABanik, Tenley Jill 21 July 2015 (has links)
Timing and duration of magmatism, involvement of fluid or assimilation of material, and geodynamic context are all important when assessing the processes by which silicic magmas are produced, erupted, or emplaced. This research relies heavily on in situ analyses of zircon, in combination with whole rock elemental and isotopic data, to investigate the causes and effects of silicic magmatism in two very different contexts.
First, in situ age and trace element analyses of zircon from ore-bearing porphyry dikes at Yerington Copper Mine, NV reveal a progressive drop in oxidation state over the ~1 Myr the dikes formed. Unlike previous studies which have found a correlation between bulk rock Cu content and oxidation state as measured by Eu and Ce anomalies in zircon from porphyry Cu systems, no correlation was found at Yerington. In addition, chemical abrasion treatment of zircon, which has been shown to improve age resolution, does not significantly change trace element or oxygen isotope compositions in zircon.
Second, this research uses in situ zircon U-Pb geochronology, trace element, and O and Hf isotope analyses in addition to whole rock elemental and isotopic data to evaluate the petrogenesis of multiple extinct silicic magmatic systems in Iceland and the role tectonism plays on their formation. Major findings are: 1) Involvement of hydrothermally altered, low-δ18O material prior to zircon crystallization in silicic systems in Iceland is ubiquitous; 2) A combination of partial melting of Icelandic crust and fractional crystallization of those melts and/or fresh mantle melts produce the vast majority of silicic units studied; magmas produced via pure partial melting or fractional crystallization are rare; 3) Rare calc-alkaline rocks at Króksfjörður volcano have distinctly different whole rock Pb, Nd, and Hf and in situ zircon Hf isotope compositions than coeval tholeiitic units, implying different petrogenetic mechanisms operated simultaneously for ~1 Myr; 4) Longevity of silicic magmatic systems in Iceland is strongly tied to rates of rifting.
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Elemental and isotopic geochemistry of crystal-melt systems: Elucidating the construction and evolution of silicic magmas in the shallow crust, using examples from southeast Iceland and southwest USAPadilla, Abraham De Jesus 23 July 2015 (has links)
Silicic magmas (>65 wt.% SiO2) play an integral role in creating permanent continental crust. Understanding how silicic magmatic systems evolve can help us better understand the processes that control whether silicic magmas remain trapped within Earths crust or ultimately reach Earths surface, culminating in volcanic eruptions. In this study, I use elemental and isotopic compositions of major and accessory minerals from diverse rock types produced by silicic magmatism in southeast Iceland and southwest USA to investigate geochemical relationships between crystals and their associated melt(s).
I present an extensive partition coefficient dataset for 8 mineral phases from a high-silica rhyolite, and demonstrate that accessory minerals (zircon, titanite, chevkinite, and apatite) exert a strong control on the distribution of rare earth and high field strength elements in a magma, while major minerals (amphibole, biotite, plagioclase, sanidine) dominantly control large ion lithophile elements. In addition, I offer a mathematical expression to estimate the relative abundances of Eu and Ce in their multivalent states (2+, 3+, and 4+), which may yield insight into the oxidation state of magmas based on the occurrence Ce and Eu anomalies in coexisting mineral phases.
I conducted a detailed geochemical study of zircons from Icelandic intrusive rocks, and show that their compositions form a coherent array consistent with the signature of zircons from Icelandic silicic volcanic rocks. I demonstrate that oxygen isotopes and hafnium isotopes (εHf) provide strong evidence for the existence of isotopically diverse magmatic sources in the Icelandic crust, including the influence of meteoric-hydrothermal processes and recycling of highly altered crust as a major contributor to silicic magmas in many Icelandic silicic magmatic systems.
The results presented here offer an additional dimension in helping us better understand the accumulation of silicic magmas and subsequent evolution of silicic magmatic systems within the Earths crust.
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