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Hydro-Physical Characterization of Media Used in Agricultural Systems to Develop the Best Management Practices for operation of an Environmentally Sustainable Agricultural EnterpriseKumar, Vivek 09 November 2012 (has links)
Florida is the second leading horticulture state in the United States with a total annual industry sale of over $12 Billion. Due to its competitive nature, agricultural plant production represents an extremely intensive practice with large amounts of water and fertilizer usage. Agrochemical and water management are vital for efficient functioning of any agricultural enterprise, and the subsequent nutrient loading from such agricultural practices has been a concern for environmentalists. A thorough understanding of the agrochemical and the soil amendments used in these agricultural systems is of special interest as contamination of soils can cause surface and groundwater pollution leading to ecosystem toxicity. The presence of fragile ecosystems such as the Everglades, Biscayne Bay and Big Cypress near enterprises that use such agricultural systems makes the whole issue even more imminent.
Although significant research has been conducted with soils and soil mix, there is no acceptable method for determining the hydraulic properties of mixtures that have been subjected to organic and inorganic soil amendments. Hydro-physical characterization of such mixtures can facilitate the understanding of water retention and permeation characteristics of the commonly used mix which can further allow modeling of soil water interactions.
The objective of this study was to characterize some of the locally and commercially available plant growth mixtures for their hydro-physical properties and develop mathematical models to correlate these acquired basic properties to the hydraulic conductivity of the mixture. The objective was also to model the response patterns of soil amendments present in those mixtures to different water and fertilizer use scenarios using the characterized hydro-physical properties with the help of Everglades-Agro-Hydrology Model.
The presence of organic amendments helps the mixtures retain more water while the inorganic amendments tend to adsorb more nutrients due to their high surface area. The results of these types of characterization can provide a scientific basis for understanding the non-point source water pollution from horticulture production systems and assist in the development of the best management practices for the operation of environmentally sustainable agricultural enterprise
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Estudo de infiltração e recarga direta em um lisímetro de laboratório / Study and infiltration recharge direct in laboratory lysimeterMartins, Patrícia Diniz 22 August 2018 (has links)
Orientador: José Anderson Batista do Nascimento / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-22T04:52:32Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: Estudos sobre a infiltração de água no solo são importantes para a determinação do escoamento superficial direto e da recarga direta de aquíferos, essenciais para a quantificação dos recursos hídricos. O presente trabalho tem com objetivo estudar os processos de produção de escoamento superficial e recarga direta de aquíferos por meio de um lisímetro de gravidade com amostra indeformada em escala de campo ensaiado em laboratório. O lisímetro foi construído a partir da retirada de uma amostra de solo com 0,6 m de diâmetro e 1,7 m de profundidade. Os procedimentos de escavação, transporte e instalação do lisímetro foram realizados dentro de um período de 6,25 horas, tempo inferior à instrumentação de uma bacia. Foi observado um amalgamento da amostra após a cravação de 0,20 m; correspondente a 10,5% da altura total de cravação, que é compatível com índices obtidos de amostradores. Foram realizadas simulações de eventos chuvosos no topo da amostra, correspondentes a uma chuva intensa de tempo de retorno de 10 anos com intervalo de sete dias e as tensões mátricas antecedentes e decorrentes dos ensaios ao longo da profundidade foram monitoradas. Os eventos chuvosos ensaiados não produziram escoamento superficial direto, porém a capacidade de infiltração foi caracterizada. A partir da obtenção de curvas de retenção para a amostra, a recarga direta foi observada com menores valores em períodos de menor umidade que correspondem às maiores tensão mátricas encontradas (15 a 58 kPa). Os maiores valores ocorreram após os eventos de precipitação. As tensões mátricas antecedentes caíram até a faixa de 0,2 a 4 kPa durante os períodos de ensaios. O uso de lisímetro em laboratório não substitui a prática de instrumentação de bacias nem o uso de lisímetros em campo. Considera-se que o uso de lisímetro em laboratório acarreta em condições ainda artificiais principalmente de precipitação e escoamento superficial direto. Ainda assim, a experimentação de uma amostra de solo indeformado em escala vertical de campo em laboratório, de acordo com os resultados obtidos neste trabalho, representa de forma aproximada o comportamento real da infiltração, percolação e produção de escoamento superficial direto encontrado em um perfil litológico raso / Abstract: Studies on water infiltration in soil are important for determining the runoff and direct recharge of aquifers, which are essential for the quantification of water resources. The goal of this work is to study the production processes of runoff and direct recharge of aquifers through a gravity lysimeter with undisturbed sample scale field tested in the laboratory. The lysimeter was constructed from the withdrawal of a soil sample with 0.6 m diameter and 1.7 m deep. The procedures for excavation, transportation and installation of the lysimeter were performed within a period of 6.25 hours, less time instrumentation of a watershed. We observed an amalgamation of the sample after the crimping of 0.20 m; corresponding to 10.5% of the total height of crimping, which is compatible with indices obtained from samplers. We simulated rainfall events on top of the sample, corresponding to an intense rain of turnaround time of 10 years with an interval of seven days and the tensions arising mátricas antecedents and tests along the depth were monitored. The rainfall events tested did not produce runoff, but the infiltration capacity was characterized. Upon obtaining retention curves for the sample, direct recharge was observed with lower values during periods of reduced moisture that correspond to higher voltage mátricas found (15-58 kPa). The highest values occurred after rainfall events. The voltages fell to background mátricas range of 0.2 to 4 kPa during periods of testing. The use of laboratory lysimeter does not replace the practice of instrumentation basins or the use of lysimeters in the field. It is considered that the use of lysimeter laboratory conditions still entails primarily artificial precipitation and runoff. Nevertheless, the experimentation of a sample of undisturbed soil at field vertical scale in the laboratory, according to the results obtained in this study represents an approximation of the actual behavior infiltration and seepage runoff production of a profile found in lithology shallow / Mestrado / Recursos Hidricos, Energeticos e Ambientais / Mestra em Engenharia Civil
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Irrigação superficial por bacias localizadas. Modelação matemática e entropia máxima. / Pit localizated superficial irrigation. Mathematic modelation and maximization of entropy.Ledezma Roman, Bruno Miguel 03 October 2007 (has links)
Cria-se, nesta pesquisa, as ferramentas de estudo de uma alternativa inovadora de irrigação localizada superficial, que consiste na escavação do terreno ao redor da base da planta na forma de um anel grosso que produza bulbos úmidos equivalentes aos gerados por qualquer um gotejador. Estas bacias deverão ser conectadas por meio de sulcos compactados que, além de servir como condutores semi-impermeáveis, criam um micro sistema de coleta de água. Capas radiculares podem ser colocadas dentro das bacias com o intuito de eliminar as perdas por evaporação, evitar o crescimento de ervas daninhas e até incrementar o rendimento da colheita. Desenvolve-se para este fim um modelo matemático misto do tipo balanço volumétrico e onda cinemática modificado com a teoria de onda de choque, que utiliza um modelo de infiltração baseada na inédita aplicação do princípio da maximização da entropia multidirecional. Este novo modelo de infiltração em comparação com os modelos de Horton, Philips e Kostiakov determina, além de menores erros padrões, maiores coeficientes de correlação, em média de 1.2% e 8.9 % e máximos de 2.5% e 68% nos infiltrômetros por sulcos e anel duplo, respectivamente. / The doctorate research creates the tools for study a new alternative of localized superficial irrigation. The system purposed consists in a ground excavation around the plant base. The form of this is same as a big ring, that produces an humid bulb in the root zone equivalent to a drooping system. This cavities need to be connected by furrows that\'s beyond serves for being a semi impermeable conductor of water creates a micro-system of water harvesting. Root layers can be placed inside of the cavities with intention to eliminate the losses for evaporation, to prevent the growth of harmful grass and until to improve the collect income. For this ending development a modify volumetric balance and cinematic wave model that incorporated a new infiltration model. This infiltration model is based in the in edit maximization of the multidirectional entropy. Comparing the new entropic model with the models of Horton, Philips and the modified model of Kostiakov, the entropic one, it was determined a lesser standard error and a bigger correlation coefficient, in average of 1.2% and 8.9 % for the furrows and double ring infiltrometers respectively and a maximum of 2.5% and 68%.
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Characterization and Removal Efficiency Comparison of Bioretention Soil Media MixturesHanson, Nathan T 01 June 2018 (has links)
Bioretention cells have become a commonly used green infrastructure technique to help infiltrate and remove contaminants from stormwater runoff. Bioretention cells are constructed from a layered or heterogeneous soil mixture designed to optimize their ability to infiltrate influent stormwater and remove contaminants carried by the water as it filters through the soil media. The soil mixture, composition, and planting vary depending the local regulatory agencies. As urbanization occurs across the United States, more natural land is converted from pervious surfaces, such as grasslands and forests, to impervious surfaces such as asphalt and concrete, to help reduce the impact of the runoff generated by this increased flow bioretention cells are an often-used method to treat stormwater. These impervious surfaces do not allow rainfall to infiltrate, and the water runs off into receiving water bodies such as rivers and streams as a non-point source pollutant. To help reduce pollutant loadings into receiving water bodies, Low Impact Development (LID) techniques were developed to reduce stormwater volume, peak flow, and contaminant loading rates. The bioretention cell is one of the most popular LID techniques and is comprised of a soil media that is either a layered or homogenous media, which is built following a regional agency’s standard. The performance of bioretention soil media is highly variable depending on the amount of each soil constituent present in the media.
This study compares five different soil mixtures from various agencies’ specifications to determine which media composition is most effective at removing total suspended solids (TSS) and nitrates, two of the most prevalent contaminates carried by stormwater. This study also compares mixtures’ hydraulic conductivity which determines the volume of water that the media can infiltrate and “treat”. To perform these tests, six columns of soil media were constructed with media depths of 91.5 cm (36 inches). Columns were dosed with either tap water (Phase I) or a synthetic stormwater blend (Phase II) to determine the amount of TSS and nitrate exported by each mixture. The soil mixture in each column was characterized to understand how soil characteristics effect the performance of the various media mixtures.
The bioretention soil media columns were all shown to be effective at removing influent TSS with an average removal rate of over 88% across all the columns, ranging from 99.9% removal to 73.6% removal. Most bioretention soil mixtures used in the test were shown to be ineffective at removing influent nitrates, with breakthrough of nitrate occurring after the first two pore volumes. Interestingly, the media with higher organic content were more effective at removing nitrates, with removal rates as high as 59.9% compared to the media with lower organic content. Hydraulic conductivity was also highly variable across the various soil media mixtures depending on the percentage of sand and fine media particles present in the media. Hydraulic conductivity ranged from a high value of 42 cm/hr to a low of 8.3 cm/hr. By comparing these results, a more effective bioretention soil media mixture can become agency standard and allow bioretention cells to have more consistent and better performance.
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Forage Improvements and Riparian Buffers for Water Quality and Sustainability: A Small Farm Management PlanSlusser, Robert S. 07 January 2005 (has links)
Black Hawk Creek was included in the Iowa Department of Natural Resources (DNR) 303(d) list of impaired waters in 1998 due to non-point sources of fecal coliform bacteria. Water quality degradation in the stream network is also impacted by excess nutrients in surface runoff from cropped fields and pastures, sedimentation erosion of streambanks from the high volume of water flow following storm events, and the pulse of enriched groundwater drained into the streams from the subsurface tile network. Rotational grazing will replace the current continuous grazing management system. Implementation includes controlling both sides of Black Hawk Creek in the permanent pastures with electric fencing, installing reinforced controlled stream crossing sites, establishing a permanent clean water distribution system and enhancing the Kentucky bluegrass dominated pastures with three cool season naturalized grass and three legume species adapted to the north central Iowa loess landscape. Multi-species ripariain buffers based on the Leopold Center for Sustainable Agriculture's model and other models based on simulating the functionality of presettlement ecosystem savannah grassland will be created between monocultures of corn and soybean fields and the stream network. Follow on studies will monitor the effectiveness of a managed forage sward, riparian buffers, and natural healing of streambanks to mitigate excess nutrient movement into the streams. / Master of Natural Resources
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Paediatric non-alcoholic fatty pancreas disease and aortic intimal medial thickness: A study identifying potential fatty infiltration of the pancreas and its association with aortic IMT in children exposed to teratogens during pregnancyThomas, Amy January 2020 (has links)
Magister Scientiae (Medical Bioscience) - MSc(MBS) / The incidence of non-communicable diseases is increasing worldwide, with South Africa being no exception. Non-communicable diseases are classified as non-infectious and are often referred to as lifestyle diseases as they are caused by common, modifiable risk factors such as unhealthy diet, obesity, tobacco use and lack of physical activity. Due to the increasing prevalence of childhood obesity diseases such as fatty pancreas and fatty liver are becoming more common. Cardiovascular disease, and more specifically atherosclerosis is the underlying cause in most adult deaths. Disease pathogenesis starts in childhood and can be detected via Aortic intima-media thickness (IMT). The developmental origins of health and disease hypothesis (DOHaD) proposes that exposures in-utero may result in persistent adaptations including alterations in metabolism.
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Étude du microbiote intratumoral et son effet sur la survie à long terme des individus atteints du cancer du seinPagé, Gabriel 08 1900 (has links)
Le microbiote humain est défini par l’ensemble des microbes habitant un site corporel en particulier. Les différents microbiotes de l’Homme, notamment le microbiote intestinal qui est le plus étudié, peuvent moduler de nombreux mécanismes biologiques dont le métabolisme et la réponse immunitaire. Un débalancement du microbiote au niveau des espèces qui le composent, ou dysbiose, a été associé à plusieurs maladies inflammatoires comme le diabète, l’obésité, mais aussi divers types de cancer. De plus, il a été démontré que les bactéries pouvaient avoir un impact sur la réponse des patients aux thérapies contre le cancer. Le cancer du sein est le cancer le plus mortel chez la femme. Or, l’étiologie de la maladie reste incertaine. Récemment, il a été montré que des bactéries pouvaient infiltrer les tissus plus profonds comme le tissu mammaire, formant un microbiote local.
Considérant l’impact que la dysbiose peut avoir sur la réponse immunitaire antitumorale et la réponse aux traitements, nous avons émis comme hypothèse qu’une présence bactérienne intratumorale similaire, en composition et en quantité, à celle du tissu normal non-cancéreux affecte la progression du cancer du sein ainsi que le devenir clinique des patientes. La présence du microbiote intratumoral du sein a donc été validée par la détection de plusieurs composants bactériens sur des coupes tumorales à l’aide de marquages moléculaires. Puis, nous avons évalué le rôle potentiel de ce microbiote en quantifiant et identifiant les espèces bactériennes présentes dans les tumeurs et les tissus normaux adjacents des patientes de notre cohorte du cancer du sein.
Nos résultats montrent une abondance moins élevée de l’ADN bactérien dans les tumeurs du sein comparativement aux tissus normaux adjacents appariés, suggérant qu’une altération du microbiote mammaire est associée au cancer. De plus, les patientes ayant un signal bactérien très faible dans leur tumeur avaient un nombre de récidives plus élevé. Cette influence de la quantité apparente de bactéries sur le devenir clinique a été observée principalement chez les patientes ayant une tumeur avancée, soit un grade ou un stade élevé, et de sous-types moléculaires Luminal HER2+, HER2+ (non-luminal) et Luminal B. Aucune relation n’a été observée entre la composition bactérienne du microbiote intratumoral mammaire et la récidive. Nos travaux suggèrent une implication pronostique et thérapeutique de la charge bactérienne du microbiote associé aux tumeurs mammaires. / The human microbiota is defined by all the microbes inhabiting a specific body site. The different human microbiota, and in particular the intestinal microbiota which is the most studied, can modulate many biological mechanisms, including metabolism and the immune response. An imbalance in the bacterial species that compose the microbiota, or dysbiosis, has been associated with several inflammatory diseases such as diabetes, obesity, but also various types of cancer. Additionally, bacteria have been shown to impact the response of patients to cancer therapy. Breast cancer is the deadliest cancer in women. However, the etiology of the disease remains uncertain. Recently, it has been shown that bacteria can infiltrate deeper tissues like breast tissue, forming a local microbiota.
Considering the impact that dysbiosis can have on the anti-tumor immune response and the response to treatments, we hypothesized that an intratumoral bacterial presence similar in composition and quantity to that of normal non-cancerous tissue affects the progression of breast cancer, as well as the clinical outcomes of patients. The presence of the intratumoral breast microbiota was therefore validated by the detection of several bacterial components on whole tumor sections using molecular staining. Then, we evaluated the potential role of this microbiota by quantifying and identifying the bacterial species present in tumors and adjacent normal tissues of patients in our breast cancer cohort.
Our results show a lower abundance of bacterial DNA in breast tumors compared to adjacent paired normal tissues, suggesting that an alteration of the mammary microbiota is associated with breast cancer. In addition, patients with a very low bacterial signal in their tumor had a higher number of recurrences. This influence of the apparent quantity of bacteria on the clinical outcomes has been observed mainly in patients with an advanced tumor, either a high grade or a high stage, and of the Luminal HER2+, HER2+ (non-luminal) and Luminal B molecular subtype. No relationship has been observed between the bacterial composition of the breast intratumoral microbiota and the recurrence. Our work suggests a prognostic and therapeutic implication of the bacterial load of the microbiota associated with breast tumors.
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Determination of Homogeneity and Isotropy of Soil Using Geophysical Methods.Khatibi Asfanjani, Danial January 2013 (has links)
Cognition of the hydraulic properties of soils is important in civil and environmental projects such as for water supply, geotechnical investigations and evaluation of pollutant spreading. This pilot project aims to develop and test a new method for characterization of the homogeneity and isotropy of different soils by using geophysical measurements. The method is based on geoelectrical (resistivity) measurements using a radial array. Using a radial array with electrode lines in various orientations crossing a midpoint at which water was infiltrated, it was possible to build a 3D-block model showing the water penetration into a soil body. Based on the infiltration pattern it was possible to evaluate the hydraulic heterogeneity and anisotropy of the material. Several common Swedish types of soils were tested. Measurement and evaluation techniques including software were developed. The project shows that geoelectrical measurements using a radial array and geoelectrical instruments available on the market can be used for rapid evaluation of the hydraulic heterogeneity and anisotropy of soils and rock.
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The Impact of Inkjet Parameters and Environmental Conditions in Binder Jetting Additive ManufacturingColton, Trenton Miles 13 December 2021 (has links)
Binder jetting is an additive manufacturing process in which a part is fabricated layer-by-layer using inkjet technology to selectively dispense binder into powder layers in a designated area. The approach gives this process significant advantages over other additive manufacturing processes such as lower cost, capability to print in a wide range of materials, and little to no heat applied. Although binder jetting has many advantages and has been successful implemented in various industries its overall rate of adoption is slow compared to other processes. This is largely due to poor mechanical properties and consistency in printing which stems from a poor understanding of the interaction between the binder droplets and the powder bed. This is evident as print parameters for new machines and new materials are primarily determined by trial and error. The purpose of this thesis is to report the impact of various inkjet print parameters and humidity on the printing process in binder jetting. The binder/powder interaction is complex and highly dynamic where picoliter-sized droplets impact the powder bed at velocities of 1-10 m/s. Current methods of predicting this interaction assume that it is based only on binder and powder properties. This work studies the impact of inkjet printing parameters that are often overlooked with these assumptions. The impact of droplet velocity, droplet spacing, and droplet inter-arrival time was evaluated based on single line formation and effective saturation levels when printed into various powder material and sizes. Higher droplet velocities were found to decrease effective saturation with larger droplets (92-212 pl). However, droplet velocity had a negligible impact on saturation when printing with smaller droplets from 30 m orifice (29-65 pl). Line formation was dependent on both droplet inter-arrival time and droplet spacing. Max droplet spacing correlated to the square root of inter-arrival time. These results can guide selection of printing parameters that maximize build rates and reduce defects in printed parts. As the binder/powder interaction is difficult to observe and often line formation has been used as a method of observation. However, no report relating line formation to full layer parts exists. Optimal parameters determined in line printing are used for full feature parts. In addition, the impact of ambient humidity on the printing process is studied. The direct use of parameters optimized for line printing in printing a part was shown to be ineffective. When droplet spacing, line spacing, and layer thicknesses are comparable, single and multiple layers can be formed. Over short exposure periods of powder to ambient humidity produces negligible difference however, extended exposure periods significantly reduce the saturation and increase part size. Surface roughness is identified as a possible source of printing defects. Surface roughness increases significantly when printing the first layer but decreases with successive layers. This demonstrates a strong interaction between layers. The surface roughness and effective saturation was insensitive to line and droplet spacing below 60 m. Steam powder conditioning reduces sensitivity of both surface roughness and saturation to printing parameters but causes bleeding beyond the part boundaries. Further research should include improved methods of predicting ideal printing parameters and connecting it based on geometry and parts size. Further research is needed to confirm impact of surface roughness on defects in binder jetting parts. Development of methods to control spread of binder in premoistened powder to take advantage of its potential.
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Peripheral IV Infiltration and Extravasation PreventionDooley, Sharon T. 26 April 2021 (has links)
No description available.
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