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Kalinsky, Ray. "Urban microcosm." Thesis, Virginia Polytechnic Institute and State University, 1990. http://hdl.handle.net/10919/77736.
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Over the course of time, the built environment has been a manifestation of human ideals and aspirations. Although these ideals, diverse and varied in each case, are only present in a small few of the buildings that are actually constructed, it ls my belief that they are the givers of meaning and identity to human culture and history. ln this thesis, l have created, at least on an embryonic level, an expression of my vision and dream of the coming together of human, urban life and nature.Master of Architecture
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Mercante, Donald Eugene. "Analysis of multispecies microcosm experiments." Diss., Virginia Tech, 1990. http://hdl.handle.net/10919/39798.
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Jabro, Nicholas Berman. "Microcosm studies of nutrient cycling in Bahamian stromatolites." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8594.
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Thesis (M.S.) -- University of Maryland, College Park, 2008.Thesis research directed by: Marine, Estuarine, Environmental Sciences Graduate Program. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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NERY, LAURA MOUTINHO. "CARICATURE: MICROCOSM OF THE ARTISTIC ISSUES IN MODERNITY." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2006. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=9068@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROA tese recupera a importância da técnica da caricatura no âmbito da discussão literária e plástica modernas em dois momentos específicos: na primeira metade do século XVIII, com o debate estabelecido por William Hogarth e Henry Fielding, num contexto em que se fixam as bases do romance; e em meados do século XIX, quando o tema é retomado por Charles Baudelaire, especialmente no ensaio Da essência do riso e das artes geralmente cômicas, de 1855. Embora tenha recebido da dupla Hogarth-Fielding uma definição pejorativa, a caricatura significou um caminho para a experiência moderna, seja pela assimilação de motivos altos e baixos na arte, pela tematização da vivência urbana ou pela valorização da psicologia dos personagens (dentro da tradição do empirismo de Locke), traduzida na exploração da fisionomia humana. Com Baudelaire, estabelece-se não só uma estética da caricatura, mas uma estética caricatural construída a partir das categorias cômico absoluto e o cômico significativo. Esse modo caricatural, acreditamos, já irrompia nas cenas morais de Hogarth. Adotamos a definição da caricatura como uma novidade no campo da arte pictórica, de acordo com Ernst Gombrich. À técnica italiana, segundo ele, estava franqueada a possibilidade de experimentação que levaria à descoberta não trivial de como criar a ilusão de vida sem qualquer ilusão de realidade. As reflexões de Hogarth e de Baudelaire dimensionam historicamente a importância do humor gráfico não só como um desafio à representação artística, mas também como elemento central de uma certa experiência da modernidade.
In this work, the relevance of caricature, both in modern literary and plastic discourses, is considered in two moments: during the first half of the XVIII century, in the interaction between William Hogarth and Henry Fielding, concurrent to the beginnings of the English novel, and in mid XIX century, when Charles Baudelaire, especially in his essay De l essence du rire et généralement du comique dans les arts plastiques, reapproaches the subject. Caricature received from Hogarth and Fielding a negative definition, but still showed a path to the modern experience, by assimilating low and high themes in art, by taking subjects from urban life and by emphasizing the psychology of characters (in the spirit of Locke s empiricism), through an exploration of the human face. Baudelaire s ideas give rise to an esthetics of caricature, built up from his concepts of significative and absolute comic. This caricatural mode, we believe, was already present in Hogarth s modern moral scenes. We take Ernst Gombrich s definition of caricature as an innovation in pictorial art. According to him, the Italian technique was allowed a freedom of experimentation which led to the nontrivial discovery of how to create the illusion of life without the illusion of reality. The arguments in Hogarth and Baudelaire describe the historical relevance of graphic humor, both as a challenge to artistic representation and as a central element of a certain kind of experience of modernity.
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Fayle, Tom Maurice. "Ant community structure in a rain forest microcosm." Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611618.
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Pettigrew, Mark. "Incarceration on death row : a microcosm of communication?" Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/incarceration-on-death-row-a-microcosm-of-communication(16b72399-490b-4aae-b4e2-4a8160a2b15c).html.
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Death row is a space across the United States that continues to expand, not only in numbers, but in the length of time inmates spend confined there. Fewer and fewer inmates are executed and death row is now increasingly the only punishment of capital convicts. This thesis examines the retributive and punitive treatment of death-sentenced offenders within that space and, by viewing that form of imprisonment as part of a communication process, it assesses the contribution it makes to the death penalty more generally in the USA to argue that death row imprisonment is crucial in sustaining the distinction of capital offenders, and the death penalty itself.Just as death row receives images from wider culture, it simultaneously generates images that complement and validate those it receives, of death sentenced offenders as dangerous monsters. These images, of offenders who require punitive detention, align with the dominant supportive rationale of capital punishment, retribution, and provide a basis for continued death penalty support in an era of declining executions.In the “hidden world” of death row, prisoners are left to be abused, mistreated, and denied privileges and opportunities available to other prisoners. The capital offender is presented by his death row incarceration as different from all other offenders serving other sentences, even life without parole. Death row incarceration communicates the worth and status of the condemned, presenting him as a dangerous, and dehumanised other, who needs to be securely detained, and restricted. Thus death row validates and justifies the cultural needs of capital punishment. Just as wider culture, including, specifically, the legal community, dictates a requirement for punitive detention, death row corroborates that image with its own in a self-affirming loop. Death row is therefore functional beyond the mere holding of offenders, it affirms cultural descriptions of the condemned and thus justifies, and provides support for, the very continuation of capital punishment itself.
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Wilkins, Robert James. "The advisor agent : a model for the dynamic integration of navigation information with an open hypermedia system." Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241162.
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Wah, Alison Yeung Yam. "Microcosm, Tillich & Tao : a critique of Tillich's ontology." Thesis, University of Leeds, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.414868.
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Das, Swati Jr. "Bioremediation of Pcb Contaminated Surface Soil: A Microcosm Study." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36501.
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This feasibility study was performed at Virginia Polytechnic Institute and State University (Blacksburg, VA) in collaboration with BioSystems Technology, Inc. (Blacksburg, VA). In this study, degradability of PCBs (Aroclor 1242) from an aged surface soil was evaluated using serum bottle microcosms containing aceticlastic methanogenic consortium, enriched from a municipal anaerobic digester. Two different experiments, "intermediate feed" and "starve and feed" were conducted by manipulating the methanogenic consortium with different amounts of acetate feeding, during 30 days of incubation. Disappearance of Aroclor 1242 in the microcosms was quantified using gas chromatography (GC). Significant differences in Aroclor 1242 removal between inoculated and uninoculated (control) microcosms were observed suggesting that the methanogenic consortium was responsible for Aroclor 1242 disappearance. However, GC-mass spectrometry (GC-MS) results could not confirm that disappearance of Aroclor 1242 was due to anaerobic dehalogenation. From another experiment, it was confirmed that removal of Aroclor 1242 was not due to evaporation losses during sample extraction.
Toxicity of an aged Aroclor 1242 contaminated surface soil was evaluated on an aceticlastic methanogenic consortium, enriched from a municipal anaerobic digester. Microcosms were set up using different amounts of soil and inoculum. Total gas production in the microcosms was monitored during 30 days of incubation, using a glass syringe. Total methane production in the microcosms was quantitated using GC. Toxicity of the soil on the methanogenic inoculum was determined based on the decreased rate of methane production in the microcosms relative to non- soil containing controls. Compared to the control, there was reduction in total methane production in soil containing microcosms. Between 3-27% reduction in total methane production was noticed in microcosms containing different amounts of soil and consortium. Reduction in methane production seemed to increase with increasing amount of soil. Whether this decrease in methane production was due to toxicity of Aroclor 1242 on the methanogenic consortium or due possibly to the toxicity of trapped oxygen in the soil could not be determined. The rate of gas production in the soil microcosm was linear.Master of Science
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High, Jessica M. "Microcosm evaluation of vinyl chloride bio-oxidation under anaerobic conditions." Connect to this title online, 2008. http://etd.lib.clemson.edu/documents/1219865442/.
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Withers, Kristine. "Detachment 101: a microcosm of the evolutionary nature of warfare." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/8854.
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Master of ArtsDepartment of History
Mark P. Parillo
Detachment 101's experiences provide a microcosm view of the evolutionary nature of warfare, and also demonstrates the understanding of Fourth Generational Warfare concepts by the Detachment.
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Araújo, Rafaela Oliveira. "Produção de biossurfactantes e potencial de degradação do óleo diesel por bactérias isoladas de ambientes contaminados por petróleo." Universidade Federal da Paraíba, 2017. http://tede.biblioteca.ufpb.br:8080/handle/tede/9395.
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Several microorganisms have the capacity to produce biosurfactants and to degrade petroleum hydrocarbons, which can be used in the bioremediation strategies for the recovery of environments polluted by petroleum and its derivatives. The present work aimed to evaluate the potential of biosurfactants production and degradation of diesel oil by bacteria isolates, as well as to evaluate the growth dynamics of bacteria introduced into seawater and soil with addition of diesel oil in laboratory conditions (microcosm experiment). Phylogenetic analysis of the isolates was performed on the basis of 16S rRNA sequences. The biosurfactant production capacity was analyzed by diesel oil emulsification, hemolysis and rhamnolipid production tests on the medium with cetyltrimethyl ammonium bromide (CTAB) and methylene blue. The presence of the genes rhlAB, involved in the synthesis of rhamnolipids and alkB, involved in the degradation of alkanes of diesel oil was evaluated by Polymerase Chain Reaction (PCR). The microcosm experiments were carried out using soil and seawater contaminated by diesel oil. Phylogenetic analysis of ten isolates of bacteria revealed that five isolates belonged to the genus Bacillus and five to the genus Pseudomonas. Emulsification of diesel oil was observed in four isolates in the Bushnell and Haas medium and in the nutrient broth. All isolates showed hemolytic activity and eight isolates produced rhamnolipids in medium with CTAB and methylene blue. The rhlAB gene was detected in four isolates, all belonging to the genus Pseudomonas, and the alkB gene in nine isolates. The results of the microcosm experiment with two isolates of P. aeruginosa introduced into soil and seawater containing 1% of diesel oil showed that their density increased from the fifth day of incubation indicating that the presence of diesel oil stimulated the growth of bacteria tested. The bacterial isolates analyzed in this study showed potential of application in bioremediation processes of environments contaminated by petroleum.
Vários microrganismos possuem a capacidade de produzir biossurfactantes e de degradar hidrocarbonetos do petróleo, os quais podem ser utilizados em estratégias de biorremediação para recuperação de ambientes poluídos pelo petróleo e seus derivados. No presente trabalho objetivou-se avaliar a produção de biossurfactantes e potencial de degradação do óleo diesel por bactérias, bem como a dinâmica de crescimento de bactérias introduzidas em água do mar e no solo com adição do óleo diesel em condições laboratoriais (experimento microcosmo). A análise filogenética dos isolados foi realizada com base de sequencias de RNAr 16S. A capacidade de produção de biossurfactantes foi analisada através dos testes de emulsificação do óleo diesel, hemólise e teste de produção de ramnolipídeos no meio com brometo de cetiltrimeltilamônio (CTAB) e azul de metileno. A presença do gene rhlAB, envolvido na síntese de ramnolipídeos e do gene alkB, envolvido na degradação de alcanos do óleo diesel foi avaliada pela Reação de Polimerase em Cadeia (PCR). Os experimentos microcosmo foram realizados utilizando solo e água do mar com adição do óleo diesel. Analise filogenética de dez isolados de bactérias revelou que cinco isolados pertenceram ao gênero Bacillus e cinco ao gênero Pseudomonas. A emulsificação do óleo diesel foi observada em quatro isolados no meio de Bushnell e Haas e no caldo nutriente. Todos os isolados apresentaram atividade hemolítica e oito isolados produziram ramnolipídeos em meio com CTAB e azul de metileno. O gene rhlAB foi detectado em quatro isolados, todos pertencentes ao gênero Pseudomonas, e gene alkB em nove isolados. Os resultados do experimento microcosmo mostraram que os dois isolados de P. aeruginosa introduzidos no solo e na água do mar contendo 1% de óleo diesel apresentaram aumento de densidade a partir do quinto dia de incubação indicando que a presença de óleo diesel estimulou o crescimento das bactérias testadas. Os isolados de bactérias analisados neste estudo exibiram potencial de aplicação em processos de biorremediação de ambientes contaminados por petróleo.
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Khan, Muhammad Irfan. "A lotic microcosm for ecological and ecotoxicological studies on benthic macroinvertebrates." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320214.
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Fang, Min. "Removal of Natural and Synthetic Steroid Hormones through Constructed Wetland Microcosm." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1292943388.
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Cowley, Nicola. "Realism-based approaches for evaluating bacterial susceptibility to antimicrobials used in home and personal care products." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/realismbased-approaches-for-evaluating-bacterial-susceptibility-to-antimicrobials-used-in-home-and-personal-care-products(58428a27-4b98-4bee-af2c-d19cd22f2617).html.
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Microbicides are used in consumer products worldwide to enhance their antibacterial potency in disinfection, for antisepsis or as preservatives. With the widespread use of these compounds, concerns have been expressed about their potential to select for reduced susceptibility. Whilst in vitro studies have reported the laboratory generation of bacterial insusceptibility for certain combinations of bacterium and microbicide, true microbicide resistance, which is defined as a change in susceptibility that is likely to affect the outcome of treatment, has not been frequently reported or observed in the environment. Importantly, risk assessments on the use of microbicides have been largely based on laboratory studies whereby pure cultures of bacteria are exposed to microbicides in aqueous solution. In use however, microbicides are formulated with various excipients and bacteria are exposed to them most commonly in complex biofilm communities. Work described in this doctoral thesis evaluates the effects of exposing bacteria to microbicides using exposure conditions intended to increase realism, with the ultimate aim of informing improved risk assessment methods that better reflect deployment of microbicides in the real-world, taking in to account the effects of formulation, growth in multi-species communities and potential reduced competiveness in adapted bacteria. Test bacteria (8 species, 7 genera) were repeatedly exposed to selected microbicides in aqueous solution and in various formulations reflecting their use in the domestic environment, such as general-purpose cleaners and laundry detergents. Minimum inhibitory concentrations, minimum bactericidal concentrations and minimum biofilm eradication concentrations were determined before and after 14 passages (P14) in the presence of microbicides (benzalkonium chloride (BAC), benzisothiazolinone (BIT), chlorhexidine (CHX), didecyldimethyl ammonium chloride (DDAC), Glydant (DMDM-hydantoin), polyhexamethylene biguanide (PHMB), thymol and triclosan) in aqueous solution or in formulation, using a previously validated gradient plating system. Bacteria were subsequently passaged a further 14 times in the absence of any antimicrobial agent to determine the stability of any adaptations (X14). In bacterial isolates that demonstrated marked changes in susceptibility, further phenotypic analysis was conducted to test for any induced alterations in antibiotic susceptibility, planktonic growth rate, biofilm formation, competitive fitness and relative pathogenicity. Exposure of microbial communities was carried out using a previously validated domestic drain biofilm simulator within constant depth film fermenters (CDFF). The CDFFs were exposed to increasing concentrations of BAC in aqueous solution or BAC formulation over a 32-week period. Changes in bacterial community composition and antimicrobial susceptibility distributions were assessed via replica plating onto selective and antimicrobial-containing agars as well as through the use of next generation sequencing technologies via the illumina Miseq platform and QIIME software. The formulation of microbicides significantly increased antibacterial and anti-biofilm potency and reduced the incidence and extent of the development of insusceptibility isolated bacteria (7 non-revertible bacteria in MBCs for microbicides, whilst 2 non-revertible bacteria in MBCs for formulations). In bacteria that develop marked changes in antimicrobial susceptibility after repeated exposure show changes to biofilm growth rates (10 increases and 6 decreases after microbicide exposure; 1 increase and 3 decreases after formulation exposure), as well as alterations in competitive fitness (6 decreases and 19 increases after microbicide exposure; whilst all exposed to formulation had decreased fitness) and virulence (9/13 decreased and 1/13 increased after microbicide exposure; 4/7 decreased and 2/7 increased after formulation exposure). In the multispecies microcosm system, long-term exposure to BAC or BAC formulation induced shifts in bacterial community dynamics and resulted in a decrease in BAC and various antibiotic susceptibilities (1 log10 reduction in the BAC system; 2.5 log10 reduction in the BAC formulation system of viable bacteria). Such shifts in community dynamics after antimicrobial treatment are theorised to be mainly due to clonal expansion of innately insusceptible bacteria (abundance of Achromobacter sp. increased by 39% in BAC system and 10% in BAC formulation system). Understanding the potential selectivity of microbicide-containing formulations is likely to better serve by testing formulations as well as actives in aqueous solutions. This highlights the need to conduct risk assessments of induced microbicide susceptibility changes using conditions that more accurately reflect their deployment.
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Harris, Craig S. "Bioaccumulation of zinc in periphyton and invertebrates, lotic field and microcosm studies." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ51353.pdf.
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Hudson, Dustin Roger. "Metropolitan Petros of Astoria microcosm of the Old Calendar Movement in America /." Theological Research Exchange Network (TREN) Access this title online, 2005. http://www.tren.com.
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Wilhite, Rhonda E. "The effects of atrazine on nitrogen cycling in a freshwater wetland microcosm." Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-08222008-063425/.
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Riedl, Verena Maria. "Development, pesticide exposure and repeatability of an aquatic, tri-trophic laboratory microcosm." Thesis, University of York, 2018. http://etheses.whiterose.ac.uk/22282/.
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The environmental risk of pesticides is routinely assessed in single-species tests. Multi-species systems are only employed once effect concentrations (divided by safety factors) compared to predicted environmental concentrations give reason for concern. However, direct chemical effects at the individual level often don’t directly translate into impacts observed at higher levels of organization because species interactions play an important role in mediating indirect chemical effects. In this thesis, I aimed to develop a tool that combines the advantages of single-species tests (repeatability, interpretability) and multi-species tests (ecological realism) for the repeatable study of indirect chemical effects mediated by ecological interactions. I show the standardization and testing of a tri-trophic laboratory scale microcosm (Pseudokirchneriella subcapitata, Ceriodaphnia dubia, Hydra viridissima) to better understand and quantify the effects of multiple stressors (e.g. chemicals, food availability and predation) on organisms and their interactions. We found close repeatability of system dynamics in the short term indicating the system’s ability to detect small pesticide effects and bottom-up and top-down effect propagation. Yet, inter-experimental differences between dynamics in controls were found in the long term. An investigation of the influences of a variety of experimental factors showed that deviations from standardized population dynamics were likely caused by medium related factors that acted on algal populations and led to bottom up effects. These likely masked the effects of a herbicide in exposure experiments and I did not gain conclusive results on direct and possibly indirect herbicide effects on grazer and predator populations. My findings demonstrate that considerable consistency and in-depth understanding of the characteristics of all system components are required to achieve repeatability even in apparently simple multi-species systems. My work illustrates possible pitfalls of tools aimed at the generation of repeatable effect data on ecologically relevant endpoints and identifies future research needs to achieve repeatable dynamics in the tri-trophic microcosm and to enhance its applicability.
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Farrell, Jonathan Bay. "Duckweed Uptake of Phosphorus and Five Pharmaceuticals: Microcosm and Wastewater Lagoon Studies." DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1212.
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Duckweed species L. turionifera and W. borealis grow on Wellsville Municipal Sewage Lagoons in northern Utah and, when harvested, contribute to the removal of phosphorus and pharmaceuticals from wastewater. Microcosm studies showed that duckweed contains an average of 1% phosphorus (dry weight) and removes 113 mg-P/m2day under 200 μmol/m2sec light. Duckweed in laboratory experiments reduced influent phosphorus ranging from 3.88 to 5.2 mg-TP/L to effluent concentrations of 0.88 mg-P/L in 3 days to 0.16 mg-P/L (0.32 mg-TP/L) with continual harvesting and a liquid retention time of 46 days. Duckweed removal of pharmaceuticals was comparable to removal by membrane bio-reactors. Duckweed removed 99% acetaminophen mainly by plant uptake; 98% progesterone primarily by absorption to plant tissue; 90% fluoxetine by adsorption with some biological removal attributed to plants; and sulfamethoxazole removal varied between 25 to 90% depending on polarity. Carbamazepine did not react with duckweed. Typical influent wastewater concentrations of the five pharmaceuticals in this study were not toxic to duckweed with an EC50 value of 614 μg/L per compound. HPLC/MS detection of pharmaceuticals in liquid samples using solid phase extraction at a neutral pH and silanized glassware produced 92-102% recoveries. Analysis of extracted solids produced lower recoveries. Solid extraction efficiencies ranged from 56-70% for samples stored for 24 hours and decreased with increasing storage time. Field growth studies showed higher than expected duckweed growth rates in the spring compared to three models due to turion germination after the ice melts. The growth rates decreased in the fall due to turion formation in preparation for winter. Harvesting duckweed from the Wellsville Municipal Sewage Lagoons should begin after full surface coverage around June 17th and end when temperatures fall below 15 °C around September 15th. Bi-weekly harvests with a starting plant density of 75 g-dry duckweed/m2 for the lagoons operating at 0.547 MGD and 5 mg-TP/L are required to physically remove enough phosphorus in order to meet the city’s 432 kg-P/yr discharge permit. A duckweed phosphorus harvesting system in Wellsville was estimated to produce enough biomass to meet the P-discharge limit until the flow increases above 0.656 MGD around the Year 2017.
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Wang, Felix Yuen-Yi. "Evaluation of Enhanced Bioremediation for Reductive Dechlorination of Tetrachloroethene (PCE): Microcosm Study." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/33093.
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Laboratory microcosm experiments were conducted to assess the potential for biostimulation and bioaugmentation as source reduction measures in support of a monitored natural attenuation remedial strategy at Naval Amphibious Base (NAB) Little Creek. Previous work with laboratory microcosms conducted under simulated natural (unamended) conditions has demonstrated that indigenous dehalorespirators were capable of partial dechlorination of tetrachloroethene (PCE) to cis-dichloroethene (cis-DCE). This study attempts to achieve complete reductive dechlorination with amendments to static microcosms to test the hypotheses that nutrient-limited or microorganism-limited conditions exist in aquifer sediments obtained from the site. The enhanced bioremediation experiments were comprised of nutrient-amended microcosms receiving additions of electron donors, mineral medium, or anaerobic digester supernatant, and dechlorinating culture-amended microcosms were inoculated with a culture capable of transforming PCE to ethene. Reductive dechlorination in the nutrient-amended microcosms proceeded to cis-DCE over a 260-day study period, at slightly higher rates than in experiments conducted with aquifer sediments from the same location under natural conditions. Inoculation of aquifer sediments with a small amount of dechlorinating culture initiated rapid transformation of PCE to vinyl chloride (VC) by day 18 of the study. Zero-order rates of PCE dechlorination in unamended, propionate-, formate-, mineral medium-, digester supernatant-, and dechlorinating culture-amended microcosms were 0.24, 0.750, 1.30, 0.339, 0.177, and 1.75 µM/day, respectively. The results of this study suggest that an engineered biostimulation approach alone may not be as beneficial for PCE source reduction at NAB Little Creek, than bioaugmentation with competent dehalorespirators, along with the inclusion of supplemental nutrients which would be available to stimulate dechlorination activity of both indigenous and introduced microorganisms.Master of Science
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Craig, Duncan L., and Duncan Craig@foodstandards gov au. "Use of microcosm and in-situ studies for the estimation of exposure risk from recreational coastal waters and sediments." Flinders University. Medicine, 2005. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20051108.093750.
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The interaction of microorganisms with sediments can enhance their survival by reducing exposure to various stressors and thus marine sediments may act as reservoirs for pathogenic microorganisms. In coastal waters there can be an increased risk of infection to humans due to the possible re-suspension of these microorganisms during recreational activities. This research attempts to more accurately identify environmental exposure in the first stage of a health risk assessment in recreational coastal waters. Techniques were developed to successfully separate microorganisms from sediment particles. Of the methods investigated, subjecting diluted sediment samples to a sonication bath for 10 minutes was found to be the most efficient separation technique over a range of sediment types. This method was therefore used in the subsequent studies to enumerate organisms from the surface sediment layer, as distinct from the water column. Faecal coliforms were enumerated by membrane filtration in both water and sediment from three Adelaide metropolitan recreational coastal sites, chosen to represent different physical sediment characteristics, over a 12-month period. All sites investigated met current National Health and Medical Research Council Guidelines for primary contact recreation. Faecal coliform concentrations were generally greater in sediment compared with overlying water for all samples. This was most evident in sediment consisting of greater silt/clay and organic carbon content (with up to 1000 times higher concentrations in the surface sediment layer compared with overlying water). For coastal recreational sites impacted by stormwater or river discharges, high faecal coliform concentrations were found to be associated with rainfall. A laboratory-based microcosm study utilising intact sediment cores was undertaken to determine the decay rates of faecal indicator organisms (E. coli, enterococci and somatic coliphage) and pathogens (Salmonella derby and S. typhimurium) in both overlying water and in various sediment types. For all organisms tested, temperature had an inverse relationship with survival. Greater decay was observed in the overlying water compared to the surface sediment layer. Small particle size and high organic carbon content was found to be more conducive to microbial survival. In general, decay rates of E. coli were significantly greater than enterococci and coliphage. Although no significant correlations were observed between decay rates of the pathogens and indicator organisms, decay of Salmonella spp. in overlying water more closely resembled that of E. coli than that of other indicators. Using decay rates measured in the microcosm study and available dose-response data, a quantitative microbial risk assessment (QMRA) utilising Monte Carlo simulation was undertaken to estimate the risk of infection to Salmonella spp. and rotavirus following exposure to recreational coastal water subject to a range of faecal contamination levels. For modelling purposes, the assumption was made that rotavirus decay was equivalent to coliphage decay. The probability of infection from rotavirus due to exposure to contaminated recreational coastal water was greater than that for Salmonella spp. under all scenarios. This increased probability of infection is linked to the high infectivity of rotavirus compared to Salmonella spp. Results of this research highlight the limited effectiveness of using prescribed faecal coliform concentrations in the water column alone to estimate the risk of exposure to pathogenic microorganisms during recreational activity at coastal areas. It demonstrated that coastal sediments act as a reservoir for both indicator and pathogenic organisms released into the coastal environment. This suggests an increased exposure risk if these organisms are resuspended back into the water column during recreational activity. A combined risk-based monitoring program would provide a more robust and reliable estimate of health risk associated with coastal recreational areas.
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Lyons, John Joseph. "The principal's microcosm: an exploration of the interplay between the leader's meaning system and school self-renewing processes." University of Southern Queensland, Faculty of Education, 2005. http://eprints.usq.edu.au/archive/00001464/.
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Despite research on the school principalship having evolved over past decades, the prevailing standpoint has largely remained an outsider's perspective upon external behavioural manifestations of principalship. Whilst valuable in their own right, such models of research accord little importance to the effect of thought and intention on behaviour. The purpose of this research was to articulate the notion of a principal's "microcosm" as a means of capturing the dynamics of meaning making in the principalship, when the cognitive world of the principal and the actual work of school leadership interact. The functional context was the expectations of catholic school authorities that schools will engage in processes of continuous self-renewal. Following comprehensive analysis of recent theoretical and research literature, a preliminary framework for the principal's microcosm was generated. A single-investigator, multiple-site case study methodology was utilised to conduct the field research, which was carried out in a provincial city of an Australian state. Three principals were selected as the subjects for in-depth exploration and analysis over a period of 16 months. A range of qualitative research strategies was employed, encompassing formal and informal interactions with the three principals and selected members of their professional communities. On the basis of the field study, a refined framework for the principal's microcosm was developed. Four major conclusions were identified. First, the notion of microcosm offers promise as an explanatory and analytical tool for focussing upon the complexities of change in school settings. Second, metaphor was observed to be integral to microcosm and its usefulness for comprehending leader behaviours was identified. The third conclusion concerned the potential of the construct microcosm for facilitating leader development through assisting individual leaders to reflect upon and to critically examine personal meanings embedded within their own professional practice. Finally, this research makes a contribution to clarifying the nature of catholic education itself.
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Scanferlato, Vjera Sostarec. "Environment risk assessment for toxic chemicals and genetically-engineered microorganisms : a microcosm approach /." Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-07282008-135357/.
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Rosella, Schluderer Laura. "Microcosm and macrocosm in Philolaus and Plato's Philebus : the metaphysics of harmonic structure." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648507.
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Petillon, Emily. "The Chronicle of William Pelhisson: A Microcosm of Early Thirteenth Century Papal Inquisition." Scholarship @ Claremont, 2019. https://scholarship.claremont.edu/scripps_theses/1244.
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This study will use Pelhisson’s account of the Toulouse inquisition of 1230-1238 as a case study into the causes of the inquisition, the mindset of the Dominicans who carried it out, and the institutionalization of the inquisition process.
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Ellis, James Brian. "The Feasibility of Bioaugmentation for the Remediation of Chlorinated Solvents: A Microcosm Study." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/41386.
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Chlorinated solvents are among the most prevalent contaminants at Superfund sites. Perchloroethylene (PCE) and its degradative byproducts pose a particular problem because of their persistence in the subsurface and their threat to ecological health. In this study, microcosms were used to test the viability of bioaugmentation as a possible remediation strategy at a PCE contaminated site at the Naval Amphibious Base at Little Creek located in Virginia Beach, Virginia. All microcosms were created in duplicate using spatially diverse soils and the bioaugmented series innoculated with a mixed microbial culture provided by the Dr. Frank Loffler. This culture has been found to be capable of completely degrading PCE to ethene. The aqueous ethene concentration was monitored over time. It is clear from the results that bioaugmentation successfully increased the degree of reductive dechlorination over their static counterpart. Without innoculation, shallow static microcosms showed an accumulation of cis-DCE, while deep soils never showed conversion beyond TCE. Shallow bioaugmented microcosms showed the production and loss of vinyl chloride indicated probable complete conversion of PCE to ethene while deep soils showed the production of cis-DCE. These differences in dechlorination between shallow and deep soils indicate a possible disparity in reduction capacity. At day 78, microcosms were spiked with higher concentrations of PCE resulting in a reduction in dechlorination activity. Static microcosms exhibited similar degradative trends but bioaugmented batches experienced dramatic reductions in dechlorination activity indicating possible inhibition effects of native organisms due to concentration or potential toxic shock. It appears that bioaugmentation is a remediation alternative worthy of further study including possible delivery methods, toxicity or inhibition effects of concentration, and fate/transport studies.Master of Science
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Pires, Juliana Gonçalves. "Effect of Myracrodruon urundeuva and Qualea grandiflora extracts on viability and activity of microcosm biofilm and prevention of enamel demineralization in vitro." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/25/25149/tde-13072018-145259/.
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The objective of this study was to evaluate the antimicrobial and anti-caries effects of two plant extracts. The first chapter dealt with a review of the literature whose objective was to discuss the antimicrobial potential of Brazilian natural agents on the biofilm related to dental caries and gingivitis/periodontal disease. The research of the articles was carried out using PubMed. We found a total of 23 papers. Most of the studies were performed using planktonic microorganisms or under clinical trials. Nineteen articles were focused on cariogenic bacteria. From these nineteen articles, eleven were also about periodontopathogenic bacteria. Four studies addressed only periodontopathogenic bacteria. The most tested Brazilian natural agents were green propolis, essential oils of Lippia sidoides and Copaifera sp. Most of the tested agents showed similar results when compared to positive control (essential oils and extracts) or better effect than negative control (green propolis). More studies involving protocols closer to the clinical condition and the use of response variables that allows understanding the mechanism of action of natural agents are necessary before the incorporation of these natural agents into dental products. The second chapter aimed to test the effect of the hydroalcoholic extracts of Myracrodruon urundeuva All. and Qualea grandiflora Mart. leaves on the viability of the microcosm biofilm and on the prevention of enamel demineralization. The microcosm biofilm was produced on bovine enamel, using human saliva pool mixed with McBain saliva (0.2% sucrose) for 14 days. The biofilm was treated daily with the extracts for 1 min. M. urundeuva at 100, 10 and 0.1 g/ml and Q. grandiflora at 100 and 0.1 g/ml reduced cell viability similarly to the positive control and significantly more than negative control. M. urundeuva at 1000, 100 and 0.1 g/ml were able to reduce the counting formation unit-CFU counting of lactobacilli sp. and Streptococcus mutans, while Q. grandiflora at 1000 and 1.0 g/ml significantly reduced the S. mutans CFU counting. On the other hand, the natural extracts did not reduce the production of extracellular polyssacharides, lactic acid and the development of enamel caries lesions. The third chapter aimed to evaluate the effect of hydroalcoholic extracts of M. urundeuva and Q. grandiflora (alone or combined) on the viability of S. mutans biofilm and the prevention of enamel demineralization. S. mutans strain (ATCC 21175) was reactivated in BHI broth. Minimum inhibitory concentration, minimum bactericidal concentration, minimum biofilm inhibitory concentration and minimum biofilm eradication concentration were determined to choose the concentrations to be tested under the biofilm model. S. mutans biofilm (5x105 CFU/ml) was produced on bovine enamel using McBain saliva with 0.2% sucrose for 3 days. The biofilm was treated daily with the extracts for 1 min. M. urundeuva (isolated or combined) at concentrations equal or higher than 0.625 mg/ml was able to reduce the bacteria viability, whereas Q. grandiflora extract alone showed antimicrobial effect at 5 mg/ml only (p<0.05). On the other hand, none of the extracts was able to reduce the development of enamel caries lesions. Despite the tested natural extracts have antimicrobial effect; they are unable to prevent caries in enamel.O objetivo foi avaliar os efeitos antimicrobiano e anti-cárie de dois extratos de plantas. O primeiro capítulo se referiu a uma revisão da literatura cujo objetivo foi discutir o potencial antimicrobiano dos agentes naturais brasileiros sobre o biofilme relacionado à cárie dentária e à gengivite/doença periodontal. A pesquisa dos artigos foi realizada usando o PubMed. Foram encontrados 23 trabalhos. A maioria dos estudos foi realizada utilizando microorganismos na fase planctônica ou ensaios clínicos. Dezenove artigos foram focados em bactérias cariogênicas. Dos dezenove artigos, onze também eram sobre bactérias periodontopatogênicas. Quatro estudos abordaram apenas bactérias periodontopatogênicas. Os agentes naturais brasileiros mais testados foram própolis verde, óleos essenciais de Lippia sidoides e Copaifera sp. Os agentes testados apresentaram resultados similares quando comparados ao controle positivo (óleos essenciais e extratos) ou melhor efeito que o controle negativo (própolis verde). Mais estudos próximos da condição clínica e o uso de variáveis de resposta que permitam entender o mecanismo de ação são necessários, para permitir a incorporação desses agentes naturais em produtos odontológicos. O segundo capítulo teve como objetivo testar o efeito dos extratos hidroalcoólicos de Myracrodruon urundeuva All. e Qualea grandiflora Mart. sobre a viabilidade do biofilme microcosmo e na prevenção da desmineralização do esmalte. O biofilme microcosmo foi produzido em esmalte bovino, utilizando pool de saliva humana misturada à saliva de McBain (0,2% de sacarose) durante 14 dias. O biofilme foi tratado diariamente com os extratos durante 1 min. M. urundeuva a 100, 10 e 0,1 g/ml e Q. grandiflora a 100 e 0,1 g/ml reduziram a viabilidade dos microrganismos de forma semelhante ao controle positivo e significativamente maior do que o controle negativo. M. urundeuva a 1000, 100 e 0,1 g/ml foi capaz de reduzir a contagem de Unidade formadora de colônia-UFC para Lactobacilos totais e Streptococcus mutans, enquanto a Q. grandiflora a 1000 e 1,0 g/ml reduziu significativamente a contagem de UFC para S. mutans. Os extratos naturais não conseguiram reduzir a produção de polissacarídeos extracelulares-PEC, ácido lático e o desenvolvimento da lesão cariosa em esmalte. O terceiro capítulo teve como objetivo avaliar o efeito dos extratos hidroalcoólicos de M. urundeuva. e Q. grandiflora (sozinhos ou combinados) sobre a viabilidade do biofilme de S. mutans e na prevenção da desmineralização do esmalte. Cepa de S. mutans (ATCC 21175) foi reativada em caldo BHI. Concentração inibitória mínima, concentração bactericida mínima, concentração inibitória mínima de biofilme e concentração de erradicação mínima de biofilme foram determinadas para escolher as concentrações a serem testadas sob o modelo de biofilme. O biofilme de S. mutans (5x105 CFU/ml) foi produzido em esmalte bovino, utilizando saliva de McBain com 0,2% de sacarose durante 3 dias. O biofilme foi tratado diariamente com os extratos durante 1 min. M. urundeuva (isolada ou combinada) nas concentrações iguais ou superiores a 0,625 mg/ml foi capaz de reduzir a viabilidade das bactérias, enquanto que o extrato da Q. grandflora apresentou efeito antimicrobiano somente a 5 mg/ml (p<0,05). Nenhum dos extratos reduziu o desenvolvimento da lesão da cárie. Apesar dos extratos naturais terem efeito antimicrobiano, são incapazes de prevenir o desenvolvimento da lesão cariosa em esmalte.
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Tozman, Naomi. "Kinder zhurnal : a microcosm of the Yiddishist philosophy and secular education movement in America." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69640.
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Using Kinder zhurnal, an American Yiddish children's literary magazine, as the focus for this thesis, the intimate relationships between the Yiddish cultural movement which began in East Europe and the Yiddish secular school movement in America are explored. As a product of and for the Sholom Aleichem Folk Institute, a now defunct educational organization, Kinder zhurnal demonstrated the key philosophical tenets of the Yiddishist education movement as it evolved.In an analysis of the Yiddishist philosophy of education parallels are drawn between modern Yiddish secular education and that of John Dewey in their humanistic emphasis and underlying pragmatism. Utilizing the parameters of the Yiddishist/Deweyian theory, an assessment to determine the practical viability of the Yiddishist concepts is made. Kinder zhurnal, as representative of Yiddishist philosophy and educational methodology, provides the microcosmic source for much of this discussion. Its close affiliation with the unique educational philosophy of the Sholom Aleichem Folk Institute provides the opportunity to examine the educational implications of teaching Yiddish as part of Jewish education.
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Holowenko, Fervone M. "Methanogenesis and fine tailings waste from oil sand extraction, a microcosm-based laboratory examination." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0010/MQ60126.pdf.
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Beitner, Nechemia Daniel. "Microcosm++ : the development of a loosely coupled object based architecture for open hypermedia systems." Thesis, University of Southampton, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318222.
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Eckman, Wayne Miles. "Brigham Young's Indian Superintendency (1851-58): A Significant Microcosm of the American Indian Experience." Diss., CLICK HERE for online access, 1989. http://patriot.lib.byu.edu/u?/MTAF,34205.
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Farmer, William S. "A microcosm study of the biodegradability of adsorbed toluene by acclimated bacteria in soils." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/44634.
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Groundwater contamination by man-made chemicals is increasingly being reported in the United States. The potential for detrimental health effects is substantial and has been addressed by the environmental engineering profession. Typically, contaminated groundwater is pumped to the surface and treated in a variety of methods including air stripping, carbon adsorption, and biodegradation. In situ biodegradation is increasingly being considered as an alternative to pump-and-treat technology.
The primary goal of this research was to determine the fate of an organic chemical adsorbed to a subsurface soil when exposed to acclimated bacteria. Toluene was chosen as a representative compound because it is a major constituent of groundwater contaminated by gasoline. In addition, toluene is known to be both biodegradable and adsorbable. Sybron Biochemical, Inc. supplied the aerobic bacteria Psgudomonas gutjga known to readily transform toluene.
Soil microcosms were established in test-tubes and conditions simulated those of a saturated, aerobic aquifer. Gas chromatography was used to quantify changes in toluene concentration due to adsorption and biodegradation. The addition of an aqueous toluene solution to sterile microcosms resulted in the rapid and extensive adsorption of toluene to the soil. Subsequent analysis revealed the slow adsorption of an additional small fraction of toluene.
Biodegradation studies entailed the addition of acclimated bacteria to sterile soil microcosms in which substantial toluene adsorption had occurred. Addition of small doses of hydrogen peroxide effectively maintained aerobic conditions for biodegradation. As a result, E, putjda was able to transform all measurable toluene in the microcosms.
Additional desorption studies revealed that a "resistant" component of toluene remained adsorbed to the soil during biodegradation. This component was neither acted upon by bacteria nor readily extractable by methylene chloride. However, slow desorption of toluene was shown to occur at a rate comparable to slow adsorption. To achieve complete removal, groundwater treatment methods must address the rate-controlled desorption of the resistant toluene component.
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Daam, Michiel Adriaan. "Influence of climatic factors and microcosm complexity on the fate and effects of pesticides." Doctoral thesis, Universidade de Aveiro, 2007. http://hdl.handle.net/10773/932.
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Doutoramento em BiologiaApesar dos estudos de microcosmo e mesocosmo terem um papel importante no procedimento de registo dos pesticidas, a extensão pelos quais os resultados dos diferentes estudos de modelos de ecossistema poderem ser extrapolados para outros casos é ainda um assunto de debate. Esta tese pretende contribuir para a discussão sobre a influência local, temporal e dos factores metodológicos nos resultados dos estudos do microcosmo. Para este efeito, foram efectuados estudos do microcosmo com água doce em condições experimentais distintas e os efeitos do tratamento e o destino comparados com os reportados em experiências similares. As experiências com pequenos microcosmos laboratoriais com aplicações únicas de clorpirifos, linurão e carbendazim nem sempre previram as respostas exactas, tal como observado em experiências com modelos de ecossistema em larga escala. Uma vez que os sistemas utilizados eram fechados e não continham sedimento nem macrófitas, os pesticidas eram mais persistentes e os valores de toxicidade calculados tornaram-se mais comparáveis com os estabelecidos nas experiências com exposição prolongada. As implicações e as recomendações para a metodologia de estudos de avaliação de risco aquático são discutidos na secção discussão geral. Uma experiência do microcosmo na Tailândia, lidando com múltiplas aplicações de clorpirifos, conduziu à conclusão que o tempo de aplicação tem uma elevada influência nos efeitos do insecticida nas comunidades de água doce. Isto é explicado em relação às fases da população das comunidades de zooplâncton no momento da aplicação. Os valores de toxicidade calculados nos estudos do microcosmo tropical depois de aplicações únicas de pesticida estavam dentro da gama (clorpirifos e carbendazim) ou mais elevado (linurão) que os reportados em estudos temperados. Assim, estes resultados suportam o uso de dados de toxicidade de estudos de ecossistemas modelo levados a cabo em zonas temperadas para a avaliação de risco ambiental em países tropicais.
Although micro- and mesocosm studies play an important role in the registration procedure of pesticides, the extent by which the results of different model ecosystem studies may be extrapolated to one another is still a matter of debate. This thesis aims to contribute to the discussion concerning the influence of spatial, temporal and methodological factors on the outcome of microcosm studies. For this purpose, freshwater microcosm studies were carried out under different experimental conditions and fate and treatment effects compared with those reported in similar experiments. Small indoor microcosm studies with single applications of chlorpyrifos, linuron and carbendazim did not always predict the exact responses as was observed in larger-scale model ecosystem studies. Since closed systems were used that did not contain sediment and macrophytes, pesticides were more persistent and calculated toxicity values were therefore generally more comparable with those reported in studies with long-term exposure. Implications and recommendations for the methodology of aquatic risk assessment studies are discussed in the general discussion section. A microcosm study in Thailand dealing with multiple chlorpyrifos applications led to the conclusion that the time of application has a large influence on the effects of the insecticide on freshwater communities. This is explained in relation to the population phase of zooplankton communities at the time of application. Threshold values calculated in tropical microcosm studies after single pesticide applications were well in range (chlorpyrifos and carbendazim) or higher (linuron) than those reported in temperate studies. These findings thus support the use of toxicity data from model ecosystem studies carried out in the temperate zone for the environmental risk assessment in tropical countries.
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Smith, Luke Lanning. "Microcosm phytoremediation of crude oil using Spartina alterniflora and simulated via a mathematica model." Thesis, University of Iowa, 2013. https://ir.uiowa.edu/etd/2634.
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Light, medium and heavy crude oils were studied at three concentrations and with two different sediments in experimental microcosm settings to determine the ability of Spartina alterniflora and associated microbes to breakdown total extractable hydrocarbons (TEH) in the water. It was a baseline experiment designed to quantify the rates of biodegradation under relatively quiescent conditions from different crude oils at moderate doses ranging from 0-150 mg/kg soil. Upon the completion of the experiment there were several key findings: (1) The lethal dosage for Spartina alterniflora was not reached within the 90 day experiment at these dosages, and all plants survived; (2) More than 97% of the total extractable hydrocarbons (TEH) were shown to be degraded by plants and rhizosphere microorganisms within the 90- day experiment; (3) The dose of oil introduced as a slick (simulated spill) on day zero did not significantly affect the results for TEH degradation within the range of dosages from 50-150 mg/g -- these dosages could be degraded by the marsh cord grass system; (4) A sediment type which was acclimated to oil for several months and one which was non-acclimated did not show significantly different results for TEH degradation in the microcosms -- both sediment systems resulted in TEH degradation over the 90-day experiment; and (5) A mathematical model was developed which simulated experiment results quite closely including TEH diffusion from the crude oil slick into the water and subsequent biodegradation.
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Wu, Yong. "Preliminary exploration of estuarine ecosystem structure at low trophic levels with a controlled microcosm." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/26210.
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In a laboratory microcosm, two kinds of salinity gradients were created to simulate the process occurring in estuarine circulation with mixing sea water and fresh water. The behaviour of the freshwater and seawater ecosystem components in relation to the salinity gradients were investigated. Seven parameters were chosen as indicators of the different trophic levels in the ecosystem or of the environmental conditions. The interaction among the different trophic levels was reflected in the development pattern of phytoplankton, nutrients, bacteria, and nanozooflagellates. The interaction among the ecosystem and environmental conditions were reflected in the difference between the different experiments with different salinity gradients and different ecosystem origin.
In stage I freshwater phytoplankton were tested on two different salinity gradients. The data showed that the freshwater biota could not pass through the salinity gradient. Most of them died or were inhibited during the mixing process. The autotrophic component in fresh water could no longer function as a autotrophic component but served as an organic substrate contributor. The inhibition of phytoplankton growth by the salinity gradient provided a condition in which the bacteria could concurrently develop in the ecosystem. In a homogenous condition with controlled flasks, the development of the autotrophic component was separated from heterotrophic bacteria over time.
In stage II, a seawater ecosystem had a different responce from that of fresh water. With an increasing salinity, the growth of phytoplankton could be limited at low salinities. This resulted in a delay of the maximum phytoplankton biomass and provided the first period of time for bacterial development before the bloom of autotrophic components. Thus bacteria formed a peak before phytoplankton developed. Seawater phytoplankton could, on the other hand, actively and quickly respond in their growth, on the salinity gradient. Thus the seawater autotrophic component may play the major role in primary production in a phytoplankton based estuarine ecosystem. The behavior of autotrophic components in both systems can have a strong effect on the rest of the components in the system; their changes could cause a great change in the whole system structure. Different developmental patterns of phytoplankton and bacteria in different experiments were explained with a conceptual diagram which summarizes the idea of energy states of an ecosystem and the function of phytoplankton and bacteria in ecosystem dynamics.
Temporal development patterns of the ecosystem components in our experiments may be extrapolated into spatial distributions if a body of water is moving seaward in an estuary. Thus a conceptual model is presented to explain the spatial distribution of many biologically important components which have often been reported in many field investigations of estuaries.Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate
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Runyon, Thomas Alvin 1963. "Microcosm experiments to enhance the bioremediation of a No.2 fuel oil-contaminated soil." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277064.
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Soil microcosm experiments were conducted to identify soil amendments which enhance the biodegradation of a No. 2 (diesel) fuel in soil. Microcosm amendments in Phase 1 included yeast extract, acetate, methane, and activated sludge. Combinations of these amendments resulted in 16 different treatments. Phase 2 soil microcosms contained combinations of methane and methanotroph additions resulting in four different treatments. Gas chromatography was used to determine the time and treatment-dependent concentration of C12-C18 n-alkanes during Phase 1 and, C14-C19 n-alkanes during Phase 2. Results from Phase 1 indicated that the most extensive biodegradation occurred in methane and activated sludge-supplemented microcosms. Acetate and/or yeast extract inhibited biodegradation by soil and/or activated sludge microorganisms. Addition of methane relieved inhibition by these amendments. Methane and/or methanotroph additions to Phase 2 microcosms did not enhance biodegradation relative to unamended microcosms. In general, n-alkanes longer than n-C12 were equally degraded in soil microcosms.
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Shillito, Alex Benjamin. "How the Heart Became Muscle: From René Descartes to Nicholas Steno." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7939.
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This dissertation addresses the heartbeat and the systems of natural philosophy that were used to explain it in the 17th century. Thus, I work in two domains of explanation. The first domain is physiology, in which William Harvey correctly ordered the heart’s systolic and diastolic motions, while René Descartes incorrectly reversed them. By looking at Harvey and Descartes’ more complete physiological models I reconsider the controversy that spun out of their divergent accounts. The second domain is the junction of physics and metaphysics, representing the frameworks of natural philosophy behind physiology. I argue that Harvey’s physiology was correct while his supporting principles were “wrong,” and Descartes’ physiology was incorrect while his supporting principles were “right.” Thus, my thesis is that Harvey was “right” but perhaps for the wrong reasons, while Descartes was “wrong” but perhaps for the right reasons. Of course, this judgement is made from a contemporary perspective. By using a contextualist approach to history, I aim to show how the controversy between Harvey and Descartes resolved in Nicolas Steno, when he discovered that the heart is a muscle.
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Lamonica, Dominique. "Capturer les interactions écologiques en microcosme sous pression chimique à travers le prisme de la modélisation." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1043/document.
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L'évaluation du risque lié aux contaminants est généralement basée sur des données collectées au cours d'essais monospécifiques (à une seule espèce). Par conséquent, les interactions entre espèces, bien qu'elles structurent les écosystèmes, ne sont pas prises en compte. Pour explorer les effets des contaminants sur la dynamique des espèces en interaction, cette thèse vise à modéliser le fonctionnement d'un microcosme de laboratoire de deux litres incluant trois espèces, la daphnie Daphnia magna, la lentille d'eau Lemna minor et la microalgue Pseudokirchneriella subcapitata, exposées à une contamination par le cadmium. La dynamique des trois espèces ainsi que leurs interactions et les effets du cadmium ont été décrits par un modèle mécaniste basé sur des équations différentielles ordinaires couplées. Les principaux processus intervenant dans ce microcosme de trois espèces ont donc été formalisés, notamment la croissance et la survie des daphnies, la croissance et la sédimentation des algues, la croissance des lentilles, le broutage des algues par les daphnies, la compétition interspécifique entre algues et lentilles et les effets du cadmium sur ces différents processus. Les paramètres du modèle ont été estimés par inférence bayésienne, en utilisant simultanément toutes les données issues de différentes expérimentations en laboratoire, réalisées au cours de la thèse spécialement pour cette étudeContaminant risk assessment is generally based on data collected during single species bioassays (including only one species). As a consequence, interactions between species that occur in ecosystems are not taken into account. To investigate the effects of contaminants on interacting species dynamics, this thesis aims at modelling the functioning of a 2-L laboratory microcosm with three species, the daphnid Daphnia magna, the duckweed Lemna minor and the microalgae Pseudokirchneriella subcapitata, exposed to cadmium contamination. We modelled the dynamics of the three species, their interactions and the effects of cadmium using a mechanistic model based on coupled ordinary differential equations. The main processes occurring in this three-species microcosm were thus formalized, including growth and survival of daphnids, growth and settling of algae, growth of duckweeds, grazing of algae by daphnids, interspecific competition between the algae and duckweeds, and the effects of cadmium on these processes. We estimated model parameters by Bayesian inference, using simultaneously all the data issued from multiple laboratory experiments specifically conducted for this study during the thesis
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Saunders, Jeffrey. "'The mortal microcosm' : creativity and the body in the fiction of Samuel Beckett, 1932-1961." Thesis, University of Reading, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358030.
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Taylor, Rebecca Elizabeth. "Micro- and microcosm : the human body and the natural environment in archaic and classical thought." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/84847/.
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This thesis examines the micro-/macrocosm model in Archaic and Classical Greek thought. The main focus of the thesis centres on medical and philosophical theories and these are examined against the background of popular beliefs and mythology. The evidence investigated will be drawn from the Hippocratic and Aristotelian Corpus. The original formation of mankind is studied in relation to the idea that mankind is a product of the natural environment and so parallels the universe in its form and processes. Owing to this, the body reacts in the same way as the natural environment does to change and the overall nature of the natural environment extends to the nature of the body and its diseases. The fact that the body changes with the weather in this way meant that physicians could predict disease patterns through predicting the weather.
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Fuma, Shoichi. "Comparative evaluation of effects of ionizing radiation and other toxic agents on an aquatic microcosm." Kyoto University, 2003. http://hdl.handle.net/2433/149539.
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Espinosa, Angona Carmen. "Assessment of the environmental parameters associated with the production and release of geosmin in a Mediterranean river." Doctoral thesis, Universitat de Vic - Universitat Central de Catalunya, 2020. http://hdl.handle.net/10803/669902.
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En los últimos años, se ha producido un incremento en el desarrollo de floraciones algales. Estas, pueden ira asociadas a la aparición de metabolitos que generan mal sabor y olor al agua, como la geosmina. La presencia de este compuesto supone un problema para los gestores de las cuencas, ya que influye en la palatabilidad del agua y en la confianza de los consumidores en las empresas potabilizadoras.
En esta tesis, se ha llevado a cabo el estudio de los parámetros fisicoquímicos y biológicos asociados con la aparición de geosmina en un río mediterráneo, y la aplicación de los resultados obtenidos en el desarrollo de un modelo predictivo de geosmina. Se ha podido concluir que, la concentración de nutrientes, la relación N:P, el caudal y la luz son factores desencadenantes de episodios de geosmina, y que es necesaria una monitorización continua de los mismos para poder predecir su aparición.En els últims anys, s'ha produït un increment en el desenvolupament de floracions algals. Aquestes, poden ira associades a l'aparició de metabòlits que generen mal gust i olor a l'aigua, com la geosmina. La presència d'aquest compost suposa un problema per als gestors de les conques, ja que influeix en la palatabilitat de l'aigua i en la confiança dels consumidors en les empreses potabilitzadores. En aquesta tesi, s'ha dut a terme l'estudi dels paràmetres fisicoquímics i biològics associats amb l’aparició de geosmina en un riu mediterrani, i l'aplicació dels resultats obtinguts, en el desenvolupament d'un model predictiu de geosmina. S'ha pogut concloure que, la concentració de nutrients, la relació N:P, el cabal i la llum són factors desencadenants d'episodis de geosmina, i que és necessària una monitorització contínua dels mateixos per poder predir la seva aparició.
In recent years, there has been an increase in algal bloom’s development. These may be associated with the appearance of metabolites that generate bad taste and odor to water, such as geosmin. The presence of this compound is a problem for the managers of the basins, since it influences the palatability of the water and the confidence of the consumers in the drinking water treatment companies. In this thesis, the study of the physicochemical and biological parameters associated with the appearance of geosmin in a Mediterranean river has been carried out, and the application of the results obtained, in the development of a predictive model of geosmin. It has been possible to conclude that the concentration of nutrients, the N:P ratio, the water flow and the light are triggering factors of geosmin episodes, and that continuous monitoring of them is necessary to be able to predict their appearance.
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Duffy, Angela. "Genetic structuring among naturally isolated dune lake populations : a microcosm of evolutionary processes on oceanic islands." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16491/.
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Oceanic islands have been used as model systems for studies of evolution and speciation as the range of island sizes coupled with their known geological chronosequence make them ideal systems for the study of spatial and temporal variations in species diversity and distributions. These processes also occur on continental islands and mainland habitats but features of oceanic islands, notably their clearly delimited boundaries, natural isolation and simple geological composition make them more amenable to study. The perched dune lakes of Fraser Island, Australia share many of the properties of oceanic islands. The naturally isolated formation of the perched lakes, clearly delimited boundaries of the freshwater habitat and phase difference compared to the surrounding, terrestrial environment have significant implications for the biota these lakes support. Inhabitants of the perched dune lakes consist of the aquatic and semi-aquatic descendents of colonisers that were able to traverse a land barrier and survive in the oligotrophic, acidic waters over subsequent generations. Barriers to ongoing gene flow among lake populations, are however likely to be different for species with different life history characteristics. I therefore sought to assess the effects of three different life history characteristics on post-colonisation interpopulation gene flow. A representative species was selected to represent one of each of the following life history characteristics: * Aquatic species confined to lake for entire life cycle - freshwater shrimp Caridina indistincta. * Semi-aquatic species capable of terrestrial dispersal - freshwater turtle Emydura krefftii. * Semi-aquatic species capable of aerial dispersal - odonate Orthetrum Boumiera. 137-250 individuals were sampled per species across six lakes separated by 1-6km. Regions of the mitochondrial genome were targeted and molecular screening methods developed and employed to assess the relative levels of post-colonisation gene flow among lake populations. Parsimony analysis of the 25 unique haplotypes identified in the species with no apparent inter-lake dispersal mechanism, the freshwater shrimp Caridina indistincta, demonstrated that there was no sharing of derived haplotypes among lake populations. Star shaped genealogies were identified in four lake populations indicative of a population expansion and mismatch distribution analysis confirmed a recent population expansion estimated to have occurred no more than 200,000 years ago. This demonstrates that each of the perched dune lakes was colonised by C.indistincta soon after their inception but that no ongoing gene flow among lake populations has occurred. The population genetic structure of the species assessed which is capable of terrestrial dispersal suggests that although this species of freshwater turtle, Emydura krefftii, is capable of overland dispersal, gene flow among lake populations is limited. Even at the small spatial scale examined in this study, E.krefftii populations displayed a pattern of isolation by distance (r=0.854, p<0.03). Nested clade analysis also suggested a pattern of restricted gene flow with some long distance dispersal in recent times with long distance dispersal and a possible range expansion occurring historically. The species examined in this study that displayed the most extensive gene flow among lake populations was the dragonfly Orthetrum boumiera. No relationship was found between genetic and geographic distance (r= -0.0852, p>0.05) and nested clade analysis could not identify a geographical association among haplotypes, indicative of panmixia. While larval life stages of this species are fully aquatic, the winged adult stages of this species appear to be connecting seemingly isolated lake populations, at least at the spatial scale examined here. The results of this study have demonstrated that these perched dune lakes provide 'island like' models for recent biogeographic processes. The pattern of colonisation and subsequent diversification identified in these populations takes the form of insitu 'genetic radiations' with those populations that are isolated forming monophyletic clades endemic to a single lake. The genetic diversity and endemism identified in this study has occurred over much smaller temporal (<500,000 years) and spatial (<6.5km) scales than in studies of oceanic island fauna. However, the mode of formation of the perched dune lakes and the implications that their natural isolation and abiotic genesis have for the evolution of colonisers of these unique habitats has resulted in them being analogous to true oceanic islands.
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Fanslow, Mary F. "Resorts in Southern Appalachia: A Microcosm of American Resorts in the Nineteenth and Early Twentieth centuries." Digital Commons @ East Tennessee State University, 2004. https://dc.etsu.edu/etd/961.
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Five resorts in East Tennessee--Montvale Springs and the Wonderland Hotel in the Smokies, Tate Spring in the Holston River Valley, Unaka Springs on the Nolichucky River, and the Cloudland Hotel at the summit of Roan Mountain--stand testament to the proposition that their region engaged fully with areas outside southern Appalachia. Their origins, clientele, and health and leisure offerings followed those of other resorts of the same time period. Moreover, the effects of national socioeconomic trends on the hotels serve as a contradiction to the stereotype of southern Appalachia as an isolated region barricaded from the outside world by mountainous topography. The East Tennessee resorts covered in this thesis indicate that the region as a whole was emblematic of national socioeconomic and cultural trends.
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Dewhurst, Emma Brown. "Revolution in the microcosm : love and virtue in the cosmological ethics of St Maximus the Confessor." Thesis, Durham University, 2017. http://etheses.dur.ac.uk/12376/.
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I explore virtue and love in Maximus the Confessor’s theology with an aim to drawing an ethics from it relevant to the present day. I use a meta-ethical framework derived from contemporary virtue ethics and look at virtue as an instance of love within the context of Maximus’ cosmic theology. Virtue becomes a path that leads us towards love – who is God Himself. Virtue is thus about movement towards theosis. I describe virtue as a relationship between humans and God, brought about through the mutual practice of a life of ascesis from humans and grace from God. I look at the mediatoral role of humans as microcosms gathering up the universe in an image of Christ’s activity. In particular I analyse the way that human activity is simultaneously cosmic and ascetic; personal and communal. The ethic of virtue that we pursue is always caught up in a conversation about what creation gathered in love looks like. Using a number of tools derived from Maximus’ thought, I suggest that this ethics will necessarily transform our current communities and personal practices. Recognising the cosmic dimension of personal behaviour means that our communities must be scrutinised as extensions of our actions. As an example, I critique the state as an inadequate form of loving relationship, illustrating its systemic reliance on violence and ideologies of alienation and hatred. I give examples of alternative ways of human organising drawn from anarchist thought that might better enable us to love and, more importantly, enable us to call to account failures to love. I conclude that to seek theosis after the manner Maximus describes involves recognising our personal and communal failures to love. His holistic understanding of human purpose can help us see the cosmic dimension to personal ascetic practice and consequently set our sights on a more cosmic vision of love here in the present world.
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Péden, Romain. "Impact du changement climatique sur le métabolisme des protéines d’une espèce clé des communautés intertidales, Mytilus edulis (L.)." Thesis, Le Havre, 2016. http://www.theses.fr/2016LEHA0015/document.
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Dans un contexte de réchauffement climatique et d'anthropisation, les organismes colonisant les espaces côtiers sont, et seront soumis, à des variations importantes de leur milieu de vie. Parmi ces organismes, la moule bleue Mytilus edulis constitue une espèce clé des écosystèmes intertidaux et est utilisée comme sentinelle. Au cours de cette thèse, des moules collectées sur des sites présentant des niveaux de contamination contrastés ont été conditionnées à deux niveaux de température différents avant une exposition à un stress thermique aigu. Des analyses protéomiques ont été réalisées pour explorer les effets de ces stress sur l'homéostasie des protéines. Une forte mortalité est observée exclusivement pour les individus issus du site pollué et conditionnés à des températures modérées. Chez les individus issus du site propre, une abondance de protéines de stress thermique et une sur-expression d'acteurs indiquant la mise en place d'un métabolisme anaérobie est observée. Les individus conditionnés à des températures plus élevées ont une meilleure réponse vis-à-vis des individus conditionnés aux températures modérées. Pour les moules provenant du site contaminé les réponses protéiques sont bien moins nettes et tendent à démontrer un effet additif délétère de la contamination et de la température. Là encore, les individus conditionnés aux températures les plus élevées répondent mieux. En conclusion, les individus au trait de vie non contaminés affichent de meilleures réponses physiologiques que les individus contaminés. De plus, les organismes dont l'historique thermique est favorable, i.e. conditionnés à des températures plus élevées, ont également des réponses amélioréesIntertidal organisms live in a fluctuating environment. The blue mussel Mytilus edulis is a key species of those ecosystems and are largely use as sentinel species. Global warming associated with anthropization will expose mussels to contaminations together with increased temperatures. In addition, more frequent heatwaves are expected. In this work, mussels were collected at two sites depicting contrasted levels of contamination and thermal exposure in microcosm were conducted. Two acclimation scenarios were set up prior to exposure to an identical acute thermal stress. In order to decipher joint effects of acclimation and contamination on protein homeostasis, gill proteome comparisons were performed. High mortality was observed only for mussels collected at the contaminated site and acclimated to current temperatures. Concerning gill proteome analysis, organisms from the pristine site exhibit high abundance of thermal stress proteins. Proteoforms involved in anaerobic metabolism were also up-regulated. Interestingly, mussels acclimated to the higher temperatures show an enhanced response compare to the one acclimated to current temperatures. Concerning mussels from the contaminated site, the response appears more confusing, excepted for heat stress protein response. This may indicate deleterious effects of combined contamination and heat stress. Therefore, organisms acclimated to higher temperature display improved responses. In conclusion, mussels with a clean life history show better physiological abilities than individuals with contaminated life history. Moreover, organisms prepared to heat stress by higher acclimation temperatures also develop a more effective response
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Morel, Journel Thibaut. "Stratégies d'introduction d'organismes dans un environnement spatialement structuré." Thesis, Nice, 2015. http://www.theses.fr/2015NICE4107/document.
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L’établissement correspond à la formation d’une population pérenne dans l’aire d’introduction. Les populations introduites ayant des effectifs faibles, elles sont sujettes à plusieurs mécanismes augmentant leurs risques d’extinction. La structure spatiale de l’aire d’introduction, une mosaïque hétérogène de patchs d’habitat appelée « paysage », peut affecter la persistance de la population introduite. L’objectif de cette thèse est d’étudier l’interaction entre cette structure spatiale et ces mécanismes, ainsi que leur impact sur l’établissement. Les recherches entreprises ont été conduites en utilisant des modèles stochastiques afin de simuler des invasions et faire émerger des prédictions, et en testant expérimentalement ces prédictions grâce à des introductions artificielles de Trichogramma chilonis en microcosmes. Ces travaux ont permis d’identifier un effet fort de la connectivité du site d’introduction, qui peut diminuer les chances d’établissement au niveau local en favorisant l’émigration depuis le site d’introduction, et augmenter les chances d’établissement à un niveau plus large en permettant la colonisation d’autres patchs dans l’aire d’introduction. Au niveau du paysage, nous avons identifié l’impact des hubs, des patchs concentrant les flux de dispersion, qui accroissent fortement la vitesse de colonisation mais diminuent le taux d’établissement. L’établissement était également favorisé par l’agrégation de la ressource et la colonisation par sa dissémination à travers le paysage. La nature stochastique des dynamiques de colonisation est telle qu’il est nécessaire de les prendre en compte pour étudier l’établissementEstablishment is an important stage of biological invasions, which corresponds to the formation of a persistent population in the introduction area. It is not trivial, as introduced populations are often small, and subject to various specific mechanisms, which increase extinction risks. The spatial structure of the introduction area, which is usually a heterogeneous mosaic of habitat patches called a “landscape”, can interact with those mechanisms and impact the introduced population persistence. This thesis objective is to study the interaction between this spatial structure and those mechanisms, as well as their impact on establishment. On the one hand, we used stochastic models to simulate invasions and formulate predictions. On the other hand, we tested these predictions by performing artificial introductions of Trichogramma chilonis in laboratory microcosms. We were able to identify the impact of the introduction site connectivity, which could decrease establishment probabilities at a local level by increasing the emigration rate from the introduction site, and increase establishment at the landscape level by increasing the colonisation rate of other patches in the introduction area. At the landscape level, we identified the impact of hubs, i.e. patches concentrating dispersal fluxes. They strongly increased colonisation speed, but also decreased establishment. The clustering of resources increased establishment, while its scattering increased colonization. Our results show that introduced population dynamics are highly sensitive to their size. The stochastic nature of colonization dynamics is also necessary to study establishment
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Yedid, Gabriel. "Changing a bit at a time : patterns and mechanisms of microevolution and macroevolution in an electronic microcosm." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33047.
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While the use of microbial model systems in experimental evolution has made great contributions to our understanding of evolutionary processes, technological limitations and the problems of transparency they cause continue to inhibit their use in understanding even the most basic evolutionary phenomena. Conventional mathematical models are too constraining in that the range of genotypes and fitnesses must be designated at the outset, and so such models cannot be used to describe truly open-ended systems. In this thesis, I use Artificial Life technology to investigate patterns and mechanisms of evolution over short and long periods of time in a simulated chemostat-type system. The system may be rendered completely transparent, and is "open" in that genotypes with unique sequences and fitness arise unpredictably through mutation and selection.The results demonstrate that Artificial Life technology is an open-ended, yet tractable system that may be used satisfactorily to investigate problems that he beyond the reach of current theory and biotechnology. (Abstract shortened by UMI.)
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Katechakis, Alexis. "Selected interactions between phytoplankton, zooplankton and the microbial food web microcosm experiments in marine and limnic habitats /." [S.l.] : [s.n.], 2005. http://edoc.ub.uni-muenchen.de/archive/00005047.
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