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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Screening biotechnologického potenciálu vybraných zástupců rodu Geobacillus a dalších příbuzných rodů / Screening of biotechnological potential of selected members of the genus Geobacillus and other related genuses

Kouřilová, Xenie January 2019 (has links)
This diploma thesis deals with selected thermophilic representatives of genera Geobacillus, Saccharococcus and Bacillus, taking screening of its biotechnological potential into account. Bacteria from the first two genera came from Czech and German collection of microorganisms, while bacteria of genus Bacillus were natural isolates. Researched strains were examined from a viewpoint of carbon source utilization and furthermore, production of biosurfactants, extracellular hydrolytic enzymes (protease, amylase, lipase, cellulase, xylanase), organic acids, antimicrobial agents and microbial plastics – polyhydroxyalkanoates was also tested. Bacteria S. thermophilus, G. uzenensis and G. zalihae evinced a substantial ability of biosurfactant production. Strains G. jurassicus, G. uzenensis, G. gargensis and G. lituanicus were capable of intensive production of all tested, technologically significant enzymes. Highest antimicrobial effects were reached with bacteria G. stearothermophilus and G. thermocatenulatus. Largest production of acetic acid was achieved with G. jurassicus and lactic acid with G. thermodenitrificans. Ability to produce polyhydroxyalkanoates was proved at genotype level by some cultures only, however at fenotype level, response was negative. On the contrary, bacteria genus Bacillus were able to produce polyhydroxyalkanoates, although in small amounts under given circumstances. With remaining researched metabolites, production ability was considerably lower, compared to genera Geobacillus and Saccharococcus.
92

[pt] MEXILHÕES PERNA PERNA (LINNAEUS, 1758) COMO BIOMONITORES DE CONTAMINAÇÃO POR HIDROCARBONETOS POLICÍCLICOS AROMÁTICOS NO MONUMENTO NATURAL DO ARQUIPÉLAGO DAS ILHAS CAGARRAS (RJ) / [en] MUSSELS PERNA PERNA (LINNAEUS, 1758) AS BIOMONITORS OF CONTAMINATION BY POLYCYCLIC AROMATIC HYDROCARBONS IN THE CAGARRAS ISLANDS NATURAL MONUMENT (RJ)

KAMILA CEZAR GRAMLICH 02 May 2023 (has links)
[pt] Os hidrocarbonetos policíclicos aromáticos (HPA) são compostos orgânicos de origem petrogênica e pirogênica, ubíquos, persistentes, bioacumuláveis em tecidos adiposos e comprovadamente carcinogênicos. O Monumento Natural do Arquipélago das Ilhas Cagarras (MONA) é uma unidade de conservação de proteção integral localizada a 4,5 km da cidade do Rio de Janeiro, cujas potenciais fontes de HPA para o local incluem o Emissário Ipanema, a Baía de Guanabara, o trânsito de grandes e pequenas embarcações, e a deposição atmosférica proveniente do alto trânsito de veículos e emissões industriais. Considerando que moluscos bivalves são biomonitores efetivos da exposição aos HPA, em fev/22 (C1) e jul/22 (C2) coletou-se cerca de 240 mexilhões da espécie Perna perna em três ilhas do MONA para avaliar o aporte de HPA oriundos de atividades antrópicas. Amostras compostas (3-5 animais) foram extraídas em triplicata utilizando extração acelerada por solvente (ASE) com purificação na célula, e purificação adicional por cromatografia em coluna. A fração de HPA foi determinada por cromatógrafo a gás acoplado a um espectrômetro de massas (GC-MS). As concentrações de (Somatório)39HPA variaram de 236 a 1378 ng g-1 , com os maiores valores encontrados em C1, níveis semelhantes aos de estudos anteriores com P. perna na região da Baía de Guanabara e algumas das ilhas do MONA (68-6271 ng g-1), sendo caracterizado, no entanto, aumento no aporte ao longo dos últimos 10 anos. O perfil geral dos contaminantes demonstra uma mistura de fontes pirolíticas e petrogênicas na região do MONA, sendo fontes prováveis a queima de combustíveis fósseis na região metropolitana e o aporte crônico de óleo, incluindo vazamentos irregulares, pelo trânsito constante de embarcações e fundeios próximos ao MONA. As concentrações de benzo[a]pireno, o (Somatório)4HPA – benz[a]antraceno, benzo[a]pireno, criseno e benzo[b]fluoranteno – e o Quociente de Equivalência Tóxica de Benz[a]pireno (TEQ BaPy) ficaram abaixo dos limiares de 5 ng g-1, 30 ng g-1 e 18 ng g-1, respectivamente, porém mais altos na amostragem realizada no verão, sugerindo um risco potencial para a qualidade de frutos do mar (moluscos) e da população humana. O cenário fornecido por um conjunto de dados limitado (apenas duas amostragens) reforça a necessidade de um programa de biomonitoramento no MONA Cagarras que inclua HPA e outras classes de contaminantes orgânicos, como as bifenilas policloradas (PCB) e pesticidas. / [en] Polycyclic aromatic hydrocarbons (PAH) are organic compounds of petrogenic and pyrogenic origin that are ubiquitous, persistent, bioaccumulative in adipose tissue, and proven to be carcinogenic. The Cagarras Islands Natural Monument (MONA) is a protected area located 4,5 km from the city of Rio de Janeiro, whose potential sources of PAH to the site include the Ipanema Outfall, Guanabara Bay, the transit of large and small vessels, and atmospheric deposition from high traffic of vehicles and industrial emissions. Considering that bivalve mollusks are effective biomonitoring organisms of exposure to PAH, in Feb/22 (C1) and Jul/22 (C2), approximately 240 mussels of the species Perna perna were collected from three MONA islands to assess the input of PAHs from anthropogenic activities. Composite samples (3-5 animals) were extracted in triplicate using accelerated solvent extraction (ASE) with purification in the cell, and additional purification by column chromatography. The PAH fraction was determined by gas chromatography-mass spectrometry (GC-MS). The concentrations of (summation)39PAH ranged from 236 to 1378 ng g-1, with the highest values found in C1, similar to previous studies with P. perna in the region of Guanabara Bay and some of the MONA islands (68-6271 ng g-1), but characterized by an increase in input over the last 10 years. The general profile of contaminants demonstrates a mixture of pyrolytic and petrogenic sources in the MONA region, with probable sources being fossil fuel combustion in the metropolitan region and chronic oil input, including irregular leaks, from the constant traffic of vessels and anchoring near the MONA. The concentrations of Benzo[a]pyrene, the (summation)4PAH – benzo[a]anthracene, chrysene, benz[b]fluoranthene, and benzo[a]pyrene – and the Toxic Equivalent Quotient of Benzo[a]pyrene (TEQ BaPy) were below the thresholds of 5 ng g-1, 30 ng g-1, and 18 ng g-1, respectively, but higher in the sampling performed in summer, suggesting a potential risk to the quality of seafood (mollusks) and the human population. The scenario provided by a limited data set (only two samplings) reinforces the need for a biomonitoring program in the Cagarras Islands Natural Monument that includes PAHs and other classes of organic contaminants, such as polychlorinated biphenyls (PCBs) and pesticides.
93

Evaluation of using bioplastics for lab consumables

Mäepea Nilsson, Lovisa, Gunnarsson, Emelie, Mardini, Sara, Nuur Yusuf, Fartun, Nyström, Jesper January 2022 (has links)
The use of plastic has increased markedly in recent years which has led to more fossil fuels being used and more plastic in nature. This is a literature study that researches on how bio- based plastics can be used instead of plastics made from fossil fuels. The report is written in collaboration with Biotage, which is a global impact tech company that wants to use plastic parts that are made of more sustainable plastic for their products. Relevant and contemporary literature is reviewed, and several alternatives are addressed. The mechanical and physical properties of the different plastics are compared. Laboratory tests are performed on bio-based polyethylene, poly (lactic acid), bio-based polypropylene, polypropylene that contains wood fibre, recycled polypropylene and fossil-based polypropylene that is currently used by Biotage. The properties and way of manufacturing the plastics is discussed according to environmental aspects, as well as cost and recycling. This leads to the result that different plastics can be used for the different parts but plastics produced from bioethanol or biomass would be a more sustainable choice than plastic from fossil fuel.
94

Action of CDK Inhibitor PHA-848125 in ER-negative Breast Cancer with MicroRNA-221/222 Overexpression

Cheung, Douglas Guy January 2017 (has links)
No description available.
95

Leprosen in der mittelalterlichen Gesellschaft / Physische Idoneität und sozialer Status von Kranken im Spannungsfeld säkularer und christlicher Wirklichkeitsdeutungen / Leprosy Sufferers in Medieval Society. / Physical Fitness and Social Status of Sick People in the Light of Contending Secular and Christian World Views

Schelberg, Antje 14 November 2001 (has links)
No description available.
96

Potentialités de production de Poly-Hydroxy-Alcanoates (PHA) chez Cupriavidus necator sur substrats de type acides gras volatifs : études cinétiques et métaboliques. / Poly-Hydroxy-Alkanoates production potentialities by Cupriavidus necator from volatile fatty acids : kinetic and metabolic studies

Grousseau, Estelle 24 February 2012 (has links)
L’accumulation de biopolymère de réserve (PolyHydroxyAlcanoates ou PHA) par la souche Cupriavidus necator, à partir de substrats de type acides gras volatils (acide butyrique, acide propionique et acide acétique) a été étudiée. Elle est induite par une limitation phosphore. Les performances atteintes lors des cultures se situent parmi les meilleures de la littérature pour ce type de substrat : jusqu’à 66 g.L-1 de biomasse totale avec un pourcentage d’accumulation massique de 88% en PHB –PolyHydroxyButyrate- ou en PHB-co-HV -PolyHydroxyButyrate-co-HydroxyValerate- comportant jusqu’à 52% de motifs d’HV.Pour chaque source carbonée, une caractérisation cinétique et stœchiométrique de la souche a été réalisée en l’absence d’effets inhibiteurs dus aux substrats acides grâce à des cultures de type Fed-Batch avec des apports non limitants et non inhibiteurs en carbone. Il a été dégagé :- un taux de croissance maximal de la souche de 0,33 h-1 pour les trois acides étudiés- une relation entre vitesse spécifique de production de PHA et taux de croissance fixée par la disponibilité et les flux de production de NADPH2 avec un découplage inverse pour les taux de croissance supérieurs à 0,05 h-1 et un couplage partiel pour les taux de croissance inférieurs- un optimum de 0,35 Cmole.Cmole-1.h-1, associé à un taux de croissance de l’ordre de 0,05 h-1.- une amélioration de la production de PHB en termes de vitesses spécifiques mais également en termes de rendements si une faible croissance résiduelle est maintenueLa réponse de la souche à un excès de substrat acide a été caractérisée via l’étude de régimes transitoires induits par des pulses sur des cultures continues préalablement stabilisées en régime permanent. Il a été montré qu’en excès de phosphore, face à un brusque excès de substrat, la souche est incapable d’adapter rapidement son taux de croissance. L’excès est donc dirigé vers la production de PHA dont les voies sont plus rapidement mobilisables. En conditions limitantes de phosphore, le substrat excédentaire est utilisé pour la production de PHA. L’inhibition par les acides se traduit par une diminution des capacités de biosynthèse de la biomasse et des PHA entrainant une réduction de l’assimilation du carbone puis une diminution des rendements de conversion. D’autre part la sensibilité d’un système continu à un excès de substrat dépend du point de fonctionnement choisi : plus il est optimal en termes de vitesse, moins le système est robuste. L’acide propionique est très inhibiteur comparé aux autres acides étudiés (dès 3-4 mM contre 30-40 mM). Il n’agit pas simplement via une accumulation excessive dans le cytoplasme mais il exerce également une inhibition spécifique des voies métaboliques.Un antagonisme entre les substrats (acide acétique et butyrique) a été constaté et expliqué grâce à une analyse des flux métaboliques. L’acide acétique est assimilé préférentiellement pour produire la biomasse, l’énergie et les cofacteurs nécessaires à la production de PHA, alors que l’acide butyrique est utilisé pour la synthèse de PHB. La proportion maximale d’acide acétique admise dans l’alimentation en fonction des conditions fixées en régime permanent est calculée et peut être limitée à 40% du carbone.Enfin il a été déterminé que si une croissance résiduelle est assurée grâce à un apport en phosphore, le pourcentage maximal d’HV dans le polymère dépend du taux d’acide propionique dans l’alimentation et ne peux dépasser 33 ± 5% sur acide propionique pur. Par contre, si aucune croissance résiduelle n’est assurée, il est possible de convertir l’acide propionique en motifs d’HV uniquement / Reserve Biopolymer (PolyHydroxyAlkanoates or PHA) accumulation by the strain Cupriavidus necator, from Volatile Fatty Acids (VFA, like butyric acid, propionic acid and acetic acid) was investigated. This production is induced by a phosphorus limitation. For this type of substrates, performances reached during cultures are among the best listed in the literature: up to 66 g.L-1 of total biomass with 88% (w/w) of PHB –PolyHydroxyButyrate- or PHB-co-HV -PolyHydroxyButyrate-co-HydroxyValerate- with a HV content up to 52 Mole%.For each carbon source, kinetic and stoechiometric characterization has been carried out thanks to Fed-Batch cultures with non-limiting and non-inhibitory carbon feed. It has been established:- a maximal growth rate of 0,33 h-1 for the three acid investigated- a relationship between specific PHA production rate and growth rate which is set by the availability and production flux of NADPH2. For growth rate above 0,05 h-1, there is an inverse coupling. For growth rate under 0,05 h-1, there is a partial coupling.- an optimum of 0,35 Cmole.Cmole-1.h-1 is associated with a growth rate of 0,05 h-1.- if a low residual growth rate is maintained, an improvement of PHB production is recorded in terms of specific production rate and yieldsThe response of the strain to an excess of acid substrate was characterized through the investigation of transient state induced by pulsed addition of substrate during continuous cultures stabilized in steady state. It was shown that in excess of phosphorus, when there is a substrate excess, the strain is unable to quickly adapt its growth rate, so the excess is directed to PHA production whose ways seem to be more easily mobilized. Under phosphorus limitation, an excess of substrate is used for PHA production. Acid inhibition results in a decrease in biomass and PHA production capacity which leads to a decrease in carbon assimilation and conversion yields. The sensitivity of a continuous system to an excess of substrate depends on the chosen operating point: the more it is optimal in terms of specific production rate, the less the system is robust. Propionic acid is highly inhibitory compared to the other acids studied (from 3-4 mM versus 30-40 mM). It does not act only via an excessive accumulation in the cytoplasm but also exerts a specific inhibition of metabolic pathways.An antagonism between substrates (acetic and butyric acid) has been established and explained thanks to the Metabolic Flux Analysis. Acetic acid is preferentially used to produce biomass, energy and cofactors for PHA synthesis, whereas butyric acid is used to product PHB. According to the conditions set during steady state, maximal content of acetic acid admitted in the feed can be calculated. It can be limited to 40% of the carbon in the feed.Finally if a growth rate is maintained thanks to a phosphorus supply, the maximal HV content in polymer is function of propionic acid in the feed and cannot exceed 33 ± 5 Mole% on pure propionic acid. Conversely, if there is no residual growth, a total conversion of propionic acid into HV is allowed
97

A batalha pela Patagônia Chilena : o processo de formulação e operação das críticas ao projeto hidrelétrico "HidroAysén" e a construção de um conflito ambiental

Aranda, Yara Paulina Cerpa January 2014 (has links)
Esta pesquisa analisa o processo de constituição do conflito ambiental em torno ao Projeto Hidrelétrico HidroAysén (PHA), proposto para Região de Aysén, Patagônia chilena. O consórcio conformado em 2006 pela empresa hispano-italiana, ENDESA (51%) e a chilena Colbún (49%), propõe a construção de um complexo hidrelétrico de cinco represas nos rios Baker e Pascua. Desde seu anúncio, o projeto foi alvo de controvérsia quanto aos possíveis impactos e denúncias de falências no estudo de impacto ambiental. Sob a reivindicação de uma “Patagônia Sem Represas”, um amplo movimento opositor ao PHA organizou-se impulsionando o debate, impedindo o andamento do empreendimento por via judicial e obtendo um relativo sucesso em termos de repercussão e adesão à “causa”. Neste cenário, o objetivo geral do estudo é compreender de que forma uma demanda transcende o local para se tornar uma demanda nacional. Deste modo, a partir da perspectiva teórica-epistemológica de Luc Boltanski (2010) e colaboradores articulada à síntese construcionista de John Hannigan (2009) investigam-se as ações e mobilizações coletivas e individuais contrárias ao PHA. Para tanto, priorizou-se decompor o fio das ações, identificando os agentes engajados (conservacionistas, produtores rurais, ONG’s, entre outros), apresentando a experiência negociada na convergência de um interesse em comum e evidenciando os objetos em que estes se apóiam para formular e referendar a validade de suas argumentações. A pesquisa de campo foi realizada entre maio e agosto de 2013, em Santiago do Chile e em quatro localidades adjacentes ao projeto em Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins, utilizando-se uma combinação de procedimentos qualitativos, como: observação, entrevistas narrativas episódicas de Flick (2008), fotografia, pesquisa documental e diário de campo. Como resultado, observou-se que as competências emergem de três situações: 1) da necessidade de instaurar a Patagônia como um bem comum por meio de uma qualificação ambiental das justificativas, colocando-a sistematicamente como algo importante para as futuras gerações; 2) das percepções quanto ao PHA, onde se destaca a disputa sobre quem são os “atingidos”; 3) e do embate entre o que é planejado localmente e o que é imposto sob égide do “desenvolvimento”. O estudo de tais competências permitiu caracterizar a tendência das ordens de justificação evocadas pelos agentes contrários ao PHA em críticas: a) ambiental e estética; b) ambiental e social; c) críticas às práticas da empresa ao modelo desenvolvimento. Por outro lado, apresentam-se as justificativas acionadas pelo ente criticado e pelo pólo favorável ao PHA: a) projeto país; b) desenvolvimento e progresso regional e nacional; e c) críticas ao ambientalismo. Por fim, averiguou-se a existência de todos os elementos necessários para a construção bem sucedida de um problema ambiental conforme os fatores elencados por Hannigan (2009). Contudo, considerou-se precipitado afirmar que a presença destes elementos são as condicionantes que tornam este conflito excepcional, ficando o indicativo da importância da realização de futuros estudos em perspectiva comparada de conflitos ambientais para maiores inferências. / This research analyses the process of formation of the conflict over environmental issues surrounding the establishment of the HidroAysén Hydropower Plant (PHA), approved for the Aysén Region, located at Chilean Patagonia. A joint venture formed in 2006 between the binational (Spanish and Italian investiment) ENDESA (51%) and the Chilean Colbún (49%), aims to build a complex of five hydroelectric power plants located in the Baker and Pascua Rivers. Since its oficial announcement, the Project has arisen intense controversy in what regards both its demages to the environment, and the probity on the issuing of enviroment certifications. An active movement of resistance has convened around the so called “Patagonia Sin Represas” (“Patagonia without dams”), providing momentum to the public debate against the PHA and obtaining favorable judicial pronouncements to obliterate the construction of the dam. This has resulted in an increase on the morale of the cause against the PHA. Against this scenario, this research aimed at comprehending in what ways do a local demand transcends the local dimension and turn into a broader demand, echoing in the breader national sphere. For that purpose, this research draws on Luc Boltanski (2010) theoretical and epistemological contribution, as well as on the constructionist synthesis as ellaborated by John Hannigan to investigate the collective and individual mobilization and actions taken against the PHA. A priority was given to the decomposition of the tread of actions taken, identifying the actors engaged (enviromenmentalists, land owners, NGO’s, etc.), in order to clarify the negotiation contained in the phenomena and the objects in which the parties rely on in the search to validate their positions. The research field has been effectuated in 2013, between may and august, in Santiago and in other four different locations adjacent to the projects Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins. There has been employed a combination of a certain number of qualitative methods for data collection: direct observation, Flick’s (2008) episodic narratives interview, photography, research on documents and notes taken in field diaries. As a result, there has been possible to observe that certain competences emerge within three given situations: 1) the necessity to instate Patagonia as common good through means of qualification of the environmental rhetoric, placing it as importante for future generations; 2) perceptions of the PHA, in especial regards to those deemed directly “affected by the dam”, and 3) the disputes between that which is planned locally and that, otherwise, is imposed under the áuspices of the “development”. The study of those competencies allowed for characterizing the tendencies in the order of justification by the critics of the PHA: a) environmental and esthetical; b) environmental and social; and c) critical to the practices assumed by the joint venture, responsible for the PHA, in terms of the present paradigm of development. On the other hand, the research also presents the arguments for the justification posed by the part being criticized, the PHA supporters and its advocates: a) project of Nation; b) development and regional and national progress; c) criticism to the environmentalist. All the elements enumerated by Hannigan (2009), and deemed as necessary for the establishment of a well succeeded environmental agenda, were detected in this research. Nevertheless, it’s been considered still early to draw affirmative conclusions as to whether the presence of these elements are a condition for the exceptionality of the conflict. Notwithstanding, this remains as an indication of the importance for the realization of future comparative studies in the same realm of research.
98

A batalha pela Patagônia Chilena : o processo de formulação e operação das críticas ao projeto hidrelétrico "HidroAysén" e a construção de um conflito ambiental

Aranda, Yara Paulina Cerpa January 2014 (has links)
Esta pesquisa analisa o processo de constituição do conflito ambiental em torno ao Projeto Hidrelétrico HidroAysén (PHA), proposto para Região de Aysén, Patagônia chilena. O consórcio conformado em 2006 pela empresa hispano-italiana, ENDESA (51%) e a chilena Colbún (49%), propõe a construção de um complexo hidrelétrico de cinco represas nos rios Baker e Pascua. Desde seu anúncio, o projeto foi alvo de controvérsia quanto aos possíveis impactos e denúncias de falências no estudo de impacto ambiental. Sob a reivindicação de uma “Patagônia Sem Represas”, um amplo movimento opositor ao PHA organizou-se impulsionando o debate, impedindo o andamento do empreendimento por via judicial e obtendo um relativo sucesso em termos de repercussão e adesão à “causa”. Neste cenário, o objetivo geral do estudo é compreender de que forma uma demanda transcende o local para se tornar uma demanda nacional. Deste modo, a partir da perspectiva teórica-epistemológica de Luc Boltanski (2010) e colaboradores articulada à síntese construcionista de John Hannigan (2009) investigam-se as ações e mobilizações coletivas e individuais contrárias ao PHA. Para tanto, priorizou-se decompor o fio das ações, identificando os agentes engajados (conservacionistas, produtores rurais, ONG’s, entre outros), apresentando a experiência negociada na convergência de um interesse em comum e evidenciando os objetos em que estes se apóiam para formular e referendar a validade de suas argumentações. A pesquisa de campo foi realizada entre maio e agosto de 2013, em Santiago do Chile e em quatro localidades adjacentes ao projeto em Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins, utilizando-se uma combinação de procedimentos qualitativos, como: observação, entrevistas narrativas episódicas de Flick (2008), fotografia, pesquisa documental e diário de campo. Como resultado, observou-se que as competências emergem de três situações: 1) da necessidade de instaurar a Patagônia como um bem comum por meio de uma qualificação ambiental das justificativas, colocando-a sistematicamente como algo importante para as futuras gerações; 2) das percepções quanto ao PHA, onde se destaca a disputa sobre quem são os “atingidos”; 3) e do embate entre o que é planejado localmente e o que é imposto sob égide do “desenvolvimento”. O estudo de tais competências permitiu caracterizar a tendência das ordens de justificação evocadas pelos agentes contrários ao PHA em críticas: a) ambiental e estética; b) ambiental e social; c) críticas às práticas da empresa ao modelo desenvolvimento. Por outro lado, apresentam-se as justificativas acionadas pelo ente criticado e pelo pólo favorável ao PHA: a) projeto país; b) desenvolvimento e progresso regional e nacional; e c) críticas ao ambientalismo. Por fim, averiguou-se a existência de todos os elementos necessários para a construção bem sucedida de um problema ambiental conforme os fatores elencados por Hannigan (2009). Contudo, considerou-se precipitado afirmar que a presença destes elementos são as condicionantes que tornam este conflito excepcional, ficando o indicativo da importância da realização de futuros estudos em perspectiva comparada de conflitos ambientais para maiores inferências. / This research analyses the process of formation of the conflict over environmental issues surrounding the establishment of the HidroAysén Hydropower Plant (PHA), approved for the Aysén Region, located at Chilean Patagonia. A joint venture formed in 2006 between the binational (Spanish and Italian investiment) ENDESA (51%) and the Chilean Colbún (49%), aims to build a complex of five hydroelectric power plants located in the Baker and Pascua Rivers. Since its oficial announcement, the Project has arisen intense controversy in what regards both its demages to the environment, and the probity on the issuing of enviroment certifications. An active movement of resistance has convened around the so called “Patagonia Sin Represas” (“Patagonia without dams”), providing momentum to the public debate against the PHA and obtaining favorable judicial pronouncements to obliterate the construction of the dam. This has resulted in an increase on the morale of the cause against the PHA. Against this scenario, this research aimed at comprehending in what ways do a local demand transcends the local dimension and turn into a broader demand, echoing in the breader national sphere. For that purpose, this research draws on Luc Boltanski (2010) theoretical and epistemological contribution, as well as on the constructionist synthesis as ellaborated by John Hannigan to investigate the collective and individual mobilization and actions taken against the PHA. A priority was given to the decomposition of the tread of actions taken, identifying the actors engaged (enviromenmentalists, land owners, NGO’s, etc.), in order to clarify the negotiation contained in the phenomena and the objects in which the parties rely on in the search to validate their positions. The research field has been effectuated in 2013, between may and august, in Santiago and in other four different locations adjacent to the projects Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins. There has been employed a combination of a certain number of qualitative methods for data collection: direct observation, Flick’s (2008) episodic narratives interview, photography, research on documents and notes taken in field diaries. As a result, there has been possible to observe that certain competences emerge within three given situations: 1) the necessity to instate Patagonia as common good through means of qualification of the environmental rhetoric, placing it as importante for future generations; 2) perceptions of the PHA, in especial regards to those deemed directly “affected by the dam”, and 3) the disputes between that which is planned locally and that, otherwise, is imposed under the áuspices of the “development”. The study of those competencies allowed for characterizing the tendencies in the order of justification by the critics of the PHA: a) environmental and esthetical; b) environmental and social; and c) critical to the practices assumed by the joint venture, responsible for the PHA, in terms of the present paradigm of development. On the other hand, the research also presents the arguments for the justification posed by the part being criticized, the PHA supporters and its advocates: a) project of Nation; b) development and regional and national progress; c) criticism to the environmentalist. All the elements enumerated by Hannigan (2009), and deemed as necessary for the establishment of a well succeeded environmental agenda, were detected in this research. Nevertheless, it’s been considered still early to draw affirmative conclusions as to whether the presence of these elements are a condition for the exceptionality of the conflict. Notwithstanding, this remains as an indication of the importance for the realization of future comparative studies in the same realm of research.
99

A batalha pela Patagônia Chilena : o processo de formulação e operação das críticas ao projeto hidrelétrico "HidroAysén" e a construção de um conflito ambiental

Aranda, Yara Paulina Cerpa January 2014 (has links)
Esta pesquisa analisa o processo de constituição do conflito ambiental em torno ao Projeto Hidrelétrico HidroAysén (PHA), proposto para Região de Aysén, Patagônia chilena. O consórcio conformado em 2006 pela empresa hispano-italiana, ENDESA (51%) e a chilena Colbún (49%), propõe a construção de um complexo hidrelétrico de cinco represas nos rios Baker e Pascua. Desde seu anúncio, o projeto foi alvo de controvérsia quanto aos possíveis impactos e denúncias de falências no estudo de impacto ambiental. Sob a reivindicação de uma “Patagônia Sem Represas”, um amplo movimento opositor ao PHA organizou-se impulsionando o debate, impedindo o andamento do empreendimento por via judicial e obtendo um relativo sucesso em termos de repercussão e adesão à “causa”. Neste cenário, o objetivo geral do estudo é compreender de que forma uma demanda transcende o local para se tornar uma demanda nacional. Deste modo, a partir da perspectiva teórica-epistemológica de Luc Boltanski (2010) e colaboradores articulada à síntese construcionista de John Hannigan (2009) investigam-se as ações e mobilizações coletivas e individuais contrárias ao PHA. Para tanto, priorizou-se decompor o fio das ações, identificando os agentes engajados (conservacionistas, produtores rurais, ONG’s, entre outros), apresentando a experiência negociada na convergência de um interesse em comum e evidenciando os objetos em que estes se apóiam para formular e referendar a validade de suas argumentações. A pesquisa de campo foi realizada entre maio e agosto de 2013, em Santiago do Chile e em quatro localidades adjacentes ao projeto em Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins, utilizando-se uma combinação de procedimentos qualitativos, como: observação, entrevistas narrativas episódicas de Flick (2008), fotografia, pesquisa documental e diário de campo. Como resultado, observou-se que as competências emergem de três situações: 1) da necessidade de instaurar a Patagônia como um bem comum por meio de uma qualificação ambiental das justificativas, colocando-a sistematicamente como algo importante para as futuras gerações; 2) das percepções quanto ao PHA, onde se destaca a disputa sobre quem são os “atingidos”; 3) e do embate entre o que é planejado localmente e o que é imposto sob égide do “desenvolvimento”. O estudo de tais competências permitiu caracterizar a tendência das ordens de justificação evocadas pelos agentes contrários ao PHA em críticas: a) ambiental e estética; b) ambiental e social; c) críticas às práticas da empresa ao modelo desenvolvimento. Por outro lado, apresentam-se as justificativas acionadas pelo ente criticado e pelo pólo favorável ao PHA: a) projeto país; b) desenvolvimento e progresso regional e nacional; e c) críticas ao ambientalismo. Por fim, averiguou-se a existência de todos os elementos necessários para a construção bem sucedida de um problema ambiental conforme os fatores elencados por Hannigan (2009). Contudo, considerou-se precipitado afirmar que a presença destes elementos são as condicionantes que tornam este conflito excepcional, ficando o indicativo da importância da realização de futuros estudos em perspectiva comparada de conflitos ambientais para maiores inferências. / This research analyses the process of formation of the conflict over environmental issues surrounding the establishment of the HidroAysén Hydropower Plant (PHA), approved for the Aysén Region, located at Chilean Patagonia. A joint venture formed in 2006 between the binational (Spanish and Italian investiment) ENDESA (51%) and the Chilean Colbún (49%), aims to build a complex of five hydroelectric power plants located in the Baker and Pascua Rivers. Since its oficial announcement, the Project has arisen intense controversy in what regards both its demages to the environment, and the probity on the issuing of enviroment certifications. An active movement of resistance has convened around the so called “Patagonia Sin Represas” (“Patagonia without dams”), providing momentum to the public debate against the PHA and obtaining favorable judicial pronouncements to obliterate the construction of the dam. This has resulted in an increase on the morale of the cause against the PHA. Against this scenario, this research aimed at comprehending in what ways do a local demand transcends the local dimension and turn into a broader demand, echoing in the breader national sphere. For that purpose, this research draws on Luc Boltanski (2010) theoretical and epistemological contribution, as well as on the constructionist synthesis as ellaborated by John Hannigan to investigate the collective and individual mobilization and actions taken against the PHA. A priority was given to the decomposition of the tread of actions taken, identifying the actors engaged (enviromenmentalists, land owners, NGO’s, etc.), in order to clarify the negotiation contained in the phenomena and the objects in which the parties rely on in the search to validate their positions. The research field has been effectuated in 2013, between may and august, in Santiago and in other four different locations adjacent to the projects Coyhaique, Cochrane, Caleta Tortel e Villa O’Higgins. There has been employed a combination of a certain number of qualitative methods for data collection: direct observation, Flick’s (2008) episodic narratives interview, photography, research on documents and notes taken in field diaries. As a result, there has been possible to observe that certain competences emerge within three given situations: 1) the necessity to instate Patagonia as common good through means of qualification of the environmental rhetoric, placing it as importante for future generations; 2) perceptions of the PHA, in especial regards to those deemed directly “affected by the dam”, and 3) the disputes between that which is planned locally and that, otherwise, is imposed under the áuspices of the “development”. The study of those competencies allowed for characterizing the tendencies in the order of justification by the critics of the PHA: a) environmental and esthetical; b) environmental and social; and c) critical to the practices assumed by the joint venture, responsible for the PHA, in terms of the present paradigm of development. On the other hand, the research also presents the arguments for the justification posed by the part being criticized, the PHA supporters and its advocates: a) project of Nation; b) development and regional and national progress; c) criticism to the environmentalist. All the elements enumerated by Hannigan (2009), and deemed as necessary for the establishment of a well succeeded environmental agenda, were detected in this research. Nevertheless, it’s been considered still early to draw affirmative conclusions as to whether the presence of these elements are a condition for the exceptionality of the conflict. Notwithstanding, this remains as an indication of the importance for the realization of future comparative studies in the same realm of research.
100

Estudio y modelación matemática del cambio metabólico de las bacterias responsables de la eliminación biológica de fósforo en el tratamiento de aguas residuales

Acevedo Juárez, Brenda 15 April 2016 (has links)
[EN] Phosphorus is very important in life because it plays an essential role in biological processes. The main use of phosphorus is in the fertilizer industry in the form of phosphates. These phosphates come mainly from phosphate rocks which might be exhausted in 50-100 years. The overexploitation of phosphate rocks has resulted in decreased quality of reserves, and it has raised the cost of extraction, processing and shipping. Moreover, phosphorus coming from wastewater, phosphate rock dissolution, and soil with an excessive supply of fertilizer, is deposited on the surface water bodies causing a serious pollution problem called eutrophication. One of the systems most used to reduced phosphorus levels in the wastewater is the enhanced biological phosphorus removal (EBPR). This process involves capturing biologically, alternating between anaerobic oxic/anoxic conditions, the wastewater phosphorus through the phosphorus accumulating organisms (PAOs). However, one of the main problems of this process is that the glycogen accumulating organisms (GAOs) compete with PAOs for volatile fatty acids (VFA). Even though there have been many studies on the factors affecting competition between PAOs and GAOs, there are still many unanswered questions regarding the metabolism of PAOs when they lack energy reserves in the form of intracellular polyphosphates (poly-P) and its effect on the population dynamics of PAOs and GAOs in an activated sludge system. Therefore, the main goal of this dissertation is to study short- and long-term the metabolic behavior of the PAOs to different levels of poly-P; to analyze the population dynamics of microorganisms involved in the process EBPR; to model mathematically that metabolic behavior; and finally, to evaluate the possible recovery of phosphorus by extracting poly-P present in the PAOs. In the short- and long-term study was observed a metabolic shift correlates with the content in poly-P so that under low contents of poly-P the PAOs are able to behave as GAOs but without a significant development of the GAO population. Although, in both studies was observed the same metabolic behavior, from the microbiological point of view were observed some differences. In the short-term, the PAO Type II clearly showed the metabolic shift, while long-term were the PAO Type I. From the experiments performed, necessary expressions (stoichiometric and kinetic) were developed to include new behaviors observed (metabolic rate) in metabolic models existing today. Monod type expressions were developed and implemented on the model of the PAOs to represent the change between the typical stoichiometric parameters of PAO and GAO metabolism. The model was calibrated and validated showing the ability to correctly represent the metabolic change of PAOs under low concentrations of poly-P. When was observed that with low concentrations of poly-P the PAOs have the ability to change its metabolism, without the process was deteriorated by the development of the GAO population, two operating strategies were evaluated to obtain a stream rich in phosphorus to allow later retrieval. The strategies studied differed in the level of extraction of the poly-P from PAOs. In the first strategy, it was extracted less than 40 % of poly-P, while the second strategy, it came to extract more than 90 % of poly-P. The second strategy showed a higher extraction efficiency, achieving recover up to 81 % of the phosphorus present in the wastewater. As a result, of work performed four articles were generated, three of them published in journals of particular importance (2 in the journal Water Research and 1 in the journal Chemical Engineering Journal) constituting the main body of this thesis. / [ES] El fósforo es de gran importancia para la vida debido a que desempeña un papel esencial en los procesos biológicos. El principal uso del fósforo está en la industria de los fertilizantes en forma de fosfatos. Estos fosfatos provienen principalmente de las rocas fosfáticas, las cuales podrían llegar a agotarse entre los próximos 50 y 100 años. La sobreexplotación de la roca fosfática, ha generado una disminución en la calidad de las reservas, y ha elevado el coste de su extracción, procesamiento y transporte marítimo. Por otra parte, el fósforo proveniente de las aguas residuales, de la disolución de las rocas fosfáticas y de los suelos con excesivo aporte de fertilizantes, se deposita en los cuerpos de aguas superficiales produciendo un grave problema de contaminación llamado eutrofización. Uno de los sistemas más empleados para reducir los niveles de fósforo en el agua residual es el proceso de eliminación biológica de fósforo (EBPR). Este proceso implica capturar biológicamente, alternando entre condiciones anaerobias óxicas/anóxicas, el fósforo del agua residual mediante organismos acumuladores de fósforo (PAOs). Sin embargo, uno de los principales problemas de este proceso, es la competencia de las PAOs con los organismos acumuladores de glucógeno (GAOs) por los ácidos grasos volátiles (AGV). Aunque si bien se han realizado muchos estudios sobre los factores que afectan la competencia entre PAOs y GAOs, existen aún muchas preguntas sin respuesta en relación al metabolismo de las PAOs cuando estas carecen de reservas energéticas en forma de polifosfatos intracelulares (poli-P) y a su efecto sobre la dinámica de las poblaciones de PAOs y GAOs en un sistema de fangos activados. Es por ello que el objetivo principal de esta tesis doctoral consiste en: estudiar a corto y largo plazo el comportamiento metabólico de las PAOs al cambiar el contenido en poli-P; analizar la dinámica poblacional de los microorganismos implicados en el proceso de EBPR; modelizar matemáticamente dicho comportamiento metabólico y por último evaluar la posible recuperación de fósforo mediante la extracción del poli-P presente en las PAOs. En el estudio a corto y largo plazo se observó un cambio metabólico correlacionado con el contenido en poli-P, de forma que a bajos contenidos de poli-P las PAOs se comportaban metabólicamente como las GAOs, pero sin que estas últimas se llegaran a desarrollar de forma significativa. A pesar de observar el mismo comportamiento metabólico en ambos estudios, desde el punto de vista microbiológico se observaron diferencias. A corto plazo, las PAO Tipo II mostraron claramente el cambio metabólico, mientras que a largo plazo fueron las PAO Tipo I. A partir de los experimentos realizados, se desarrollaron las expresiones necesarias (estequiométricas y cinéticas) para incluir los nuevos comportamientos observados (cambio metabólico) en los modelos metabólicos existentes en la actualidad. Expresiones tipo Monod fueron desarrolladas e implementadas en el modelo de las PAOs para representar el cambio entre los parámetros estequiométricos típicos del metabolismo PAO y GAO. El modelo fue calibrado y validado mostrando la capacidad de representar correctamente el cambio metabólico de las PAOs a concentraciones bajas de poli-P. Al observar que las PAOs tienen la habilidad de cambiar su metabolismo a bajas concentraciones de poli-P, sin que se deteriorara el proceso por el desarrollo de las GAOs, se evaluaron dos estrategias de operación para la obtención de una corriente rica en fósforo que permita su posterior recuperación. Las estrategias estudiadas se diferenciaban en el nivel de extracción de poli-P de las PAOs. En la primera estrategia se extraía menos del 40 % de poli-P, mientras que en la segunda estrategia se llegaba a extraer más del 90 % de poli-P. La segunda estrategia mostró una eficacia de extracción superior, consiguiendo recuperar hasta el 81 / [CAT] El fòsfor és de gran importància per a la vida a causa que exerceix un paper essencial en els processos biològics. El principal ús del fòsfor està en la indústria dels fertilitzants en forma de fosfats. Aquests fosfats provenen principalment de les roques fosfatades, les quals podrien arribar a esgotar-se entre els pròxims 50 i 100 anys. La sobreexplotació de la roca fosfatada, ha generat una disminució en la qualitat de les reserves, i ha elevat el cost de la seua extracció, processament i transport marítim. D'altra banda, el fòsfor provinent de les aigües residuals, de la dissolució de les roques fosfatades i dels sòls amb excessiva aportació de fertilitzants, es diposita en els cossos d'aigües superficials produint un greu problema de contaminació anomenat eutrofització. Un dels sistemes més utilizats per a reduir els nivells de fòsfor en l'aigua residual és el procés d'eliminació biològica de fòsfor (EBPR). Aquest procés implica capturar biològicament, alternant entre condicions anaeròbies aeròbies/anòxies, el fòsfor de l'aigua residual mitjançant organismes acumuladors de fòsfor (PAOs). No obstant açò, un dels principals problemes d'aquest procés, és la competència de les PAOs amb els organismes acumuladors de glucogen (GAOs) pels àcids grassos volàtils (AGV). Encara que si bé s'han realitzat molts estudis sobre els factors que afecten la competència entre PAOs i GAOs, existixen encara moltes preguntes sense resposta en relació al metabolisme de les PAOs quan aquestes careixen de reserves energètiques en forma de polifosfat intracel·lulars (poli-P) i al seu efecte sobre la dinàmica de les poblacions de PAOs i GAOs en un sistema de fangs activats. És per això que l'objectiu principal d'aquesta tesi doctoral consisteix en: estudiar a curt i llarg termini el comportament metabòlic de les PAOs en canviar el contingut en poli-P; analitzar la dinàmica poblacional dels microorganismes implicats en el procés de EBPR; modelatge matemàticament d'aquest comportament metabòlic i finalment avaluar la possible recuperació de fòsfor mitjançant l'extracció del poli-P present en les PAOs. En l'estudi a curt i llarg termini es va observar un canvi metabòlic correlacionat amb el contingut en poli-P, de manera que a baixos continguts de poli-P les PAOs es comportaven metabolicament com les GAOs, però sense que aquestes últimes s'arribaren a desenvolupar de forma significativa. Malgrat observar el mateix comportament metabòlic en tots dos estudis, des del punt de vista microbiològic es van observar diferències. A curt termini, les PAO Tipus II van mostrar clarament el canvi metabòlic, mentre que a llarg termini van ser les PAO Tipus I. A partir dels experiments realitzats, es van desenvolupar les expressions necessàries (estequiomètriques i cinètiques) per a incloure els nous comportaments observats (canvi metabòlic) en els models metabòlics existents en l'actualitat. Expressions tipus Monod van ser desenvolupades e implementades en el model de les PAOs per a representar el canvi entre els paràmetres estequiomètrics típics del metabolisme PAO i GAO. El model va ser calibrat i validat mostrant la capacitat de representar correctament el canvi metabòlic de les PAOs a concentracions baixes de poli-P. En observar que les PAOs tenen l'habilitat de canviar el seu metabolisme a baixes concentracions de poli-P, sense que es deteriorara el procés pel desenvolupament de les GAOs, es varen avaluar dues estratègies d'operació per a l'obtenció d'un corrent ric en fòsfor que permeta la seua posterior recuperació. Les estratègies estudiades es diferenciaven en el nivell d'extracció de poli-P de les PAOs. En la primera estratègia es va extraure menys del 40 % de poli-P, mentre que en la segona estratègia s'arribava a extraure més del 90 % de poli-P. La segona estratègia va mostrar una eficàcia d'extracció superior, aconseguint recuperar fins al 81 % del fòsfor p / Acevedo Juárez, B. (2016). Estudio y modelación matemática del cambio metabólico de las bacterias responsables de la eliminación biológica de fósforo en el tratamiento de aguas residuales [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/62585 / TESIS

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