L'œdème cérébral et l'hypoxie cérébrale post-traumatiques sont les acteurs principaux de l'apparition des lésions ischémiques secondaires. L'erythropoïétine (Epo) sous sa forme recombinante humaine possède une activité anti-oedémateuse dans un modèle expérimental de TC diffus. Son action sur l'hypoxie cérébrale post-traumatique reste néammoins méconnue. De plus, les effets indésirables hématologiques de l'Epo ont conduit à la synthèse de dérivés de l'Epo ne possèdant pas d'activité hématopoïétique comme l'érythropoïetine carbamylée (CEpo). Dans ce contexte, mon travail de thèse a eu pour but d'évaluer les propriétés de l'Epo et de la CEpo dans le modèle de TC diffus. Un traitement intraveineux par CEpo à la dose de 50 µg/Kg a ainsi permis de diminuer précocemment l'œdème cérébral post-traumatique évalué in vivo par IRM de diffusion et ex vivo par gravimétrie spécifique. Cette propriété a impliqué l'inhibition de la phosphorylation de la voie Erk et s'est accompagnée de l'amélioration des fonctions motrices et cognitives jusqu'à 10 jours après le TC. Après une étude de validation sur des rats sains soumis à différentes conditions d'oxygénation, une méthode de mesure IRM de la saturation locale en oxygène (lSO2) cérébrale combinant l'effet BOLD avec la mesure du volume sanguin cérébral a montré une diminution de l'oxygénation cérébrale post-traumatique. Cette hypoxie cérébrale n'était pas en lien avec une diminution du débit sanguin cérébral attestée par méthode de premier passage d'un agent de constraste. Un collapsus des capillaires cérébraux était par ailleurs retrouvé en microscopie électronique. L'Epo à la dose de 5000 UI/Kg a été capable de restaurer l'oxygénation cérébrale en diminuant l'œdème astrocytaire péricapillaire. L'ensemble de ce travail a permis d'établir les bénéfices d'un traitement par Epo ou par CEpo sur l'œdème cérébral et l'hypoxie cérébrale post-traumatiques. / Post-traumatic brain oedema and brain hypoxia play a key role for the development of secondary ischaemic lesions. Erythopoïetin (Epo) is an anti-oedematous agent in the impact-acceleration model. However its action on brain hypoxia remains unkonwn. Neuroprotective derivatives of Epo that lack haematopoïétic properties, like carbamylated Epo (CEpo), have been developped to counter Epo side effects. In this context, our study aimed to assess the effect of Epo and CEpo on post-traumatic diffuse brain oedema and brain oxygenation. CEpo (50 µg/Kg) decreased brain oedema assessed by diffusion-weighted MRI and specific gravimetry 6 hours after the trauma. The anti-oedematous effect of CEpo was linked to Erk inhibition and was associated with an improvement of cognitive and motor functions, evaluated until 10 days after the insult. MRI using the combination of BOLD contrast and blood volume fraction measurement demonstrated a decrease of local brain oxygenation in our model, without franck ischemia (measurement of mild transit time by a first passage method). Epo (5000 UI/Kg) improved brain oxygenation by decreasing post-traumatic cerebral capillaries collapse due to astrocytic end-foot swelling. All these results demonstrated that Epo and CEpo could be seen as promising neuroprotective agents in traumatic brain injury.

abstract: The application of microalgal biofilms in wastewater treatment has great advantages such as abolishing the need for energy intensive aerators and recovering nutrients as energy, thus reducing the energy requirement of wastewater treatment several-fold. A 162 cm2 algal biofilm reactor with good wastewater treatment performance and a regular harvesting procedure was studied at lab scale to gain an understanding of effectual parameters such as hydraulic retention time (HRT; 2.6 and 1.3 hrs), liquid level (LL; 0.5 and 1.0 cm), and solids retention time (SRT; 3 and 1.5 wks). A revised synthetic wastewater “Syntho 3.7” was used as a surrogate of domestic primary effluent for nutrient concentration consistency in the feed lines. In the base case (2.6 hr HRT, 0.5 cm LL, and 3 wk SRT), percent removals of 69 ± 2 for total nitrogen (TN), 54 ± 21 for total phosphorous (TP), and 60 ± 7 for chemical oxygen demand (COD) were achieved and 4.0 ± 1.6 g/m2/d dry biomass was produced. A diffusion limitation was encountered when increasing the liquid level, while the potential to further decrease the HRT remains. Nonlinear growth kinetics was observed in comparing SRT variations, and promoting autotrophic growth seems possible. Future work will look towards producing a mathematical model and further testing the aptness of this system for large-scale implementation. / Dissertation/Thesis / Masters Thesis Chemical Engineering 2016

A câmara hiperbárica, equipamento pelo tratamento de diversos tipos de doenças ou síndromes, possui uma restrição muito grande quanto à instrumentação biomédica utilizada para monitoramento dos pacientes, devido ao alto risco de fogo ou explosão, por trabalhar com oxigênio (O2)sob pressão. No presente trabalho é descrito o desenvolvimento de um dispositivo biotelemétrico ativo, porém de baixo consumo e menor possível envolvida, capaz de monitorar, em tempo real, o sinal de ECG de um paciente sob tratamento hiperbárico. Para minimizar a possibilidade de se gravar níveis de calor suficientes para iniciar uma explosão,optou-se pelo uso de circuitos eletrônicos que, comparativamente, pudessem operar com os menores níveis de energia. Além disso, procurou-se evitar o uso de materiais que em contato com o O2 puro pudessem causar reações químicas que levassem a uma explosão. Neste sentido, optou-se por alimentar o dispositivo usando-se células fotovoltaícas, evitando assim o uso de baterias. Para se chegar a este desenvolvimento, estudaram-se os níveis de campo elétrico necessários para a deflagração de faíscas elétricas (Curvas de Paschen) dentro de uma câmara hiperbárica protótipo contendo O2 sob pressão. Os resultados definem uma relação segura entre a tensão aplicada e a distância entre as partes condutoras de um circuito eletrônico dentro da câmara (trilhas da placa de circuito impresso ou terminais de componentes). / Hyperbaric chambers are a kind of equipament used to treat several illness or syndromes. However, it is very dangerous whenever electronic instruments are used inside it, because the chamber has oxygen (O2) under pressure and the equipment can originate fires, specially due to the generation of sparks. In the present work, it is described the development of an active biotelemetric device. The circuit is capable to monitor, in real time, the ECG signal of a patient during hyperbaric treatment. To minimize the possibility of generating temperature values high enough to initiate an explosion, it was chosen to use electronic circuits that, comparative, could operate with low levels of energy. Moreover, materials that when in contact with pure O2 could cause chemical reactions that would lead to an explosion, have been avoided. In this direction, it was chosen to feed the device using photovoltaic cells, thus avoiding the use of batteries. To reach this development, the necessary levels of electric field for the deflagration of electric sparks have been studied (by Paschen’s Curves) and tests inside a prototype hyperbaric chamber, using O2 under pressure, have been carried out. The final results define a safe relation between applied voltage and the conductive electronic circuit parts inside the chamber (copper trace and pads of the printed circuit board).

O objetivo deste trabalho foi avaliar os efeitos do monossialogangliosídio (GM1), da câmara de oxigenoterapia hiperbárica e de ambos no tratamento da lesão medular experimental em ratos. Trinta e dois ratos Wistar com lesão medular foram divididos em 4 grupos: um grupo recebeu o monossialogangliosídio (GM1), um segundo foi submetido à oxigenoterapia hiperbárica, um terceiro recebeu os dois tratamentos e um quarto não recebeu tratamento (controle). Não houve diferença significativa entre os grupos na análise histológica, em todas as variáveis (necrose, hemorragia, hiperemia e degeneração cística, p>0,06). Também não houve nenhuma diferença na comparação entre os lados direito e esquerdo nos testes funcionais (p>0,06 para todos). Não foram encontradas diferenças nos testes motores, na comparação entre os grupos após 2, 7 21 e 28 dias de lesão medular. Mas, na avaliação após 14 dias, o Grupo 3, o qual recebeu a terapia combinada, mostrou um escore BBB significantemente maior que os outros grupos (p=0,015). Na avaliação de 28 dias, houve uma tendência dos Grupos 1 (GM1) e 3 (terapia combinada) apresentarem um escore BBB maior que o do Grupo 4 (controle), embora sem significância estatística (p=0,057). Concluiu-se que, quanto aos índices motores, a utilização do GM-1 tem efeito benéfico, embora sem diferença estatisticamente significante e que o efeito benéfico do GM-1 é antecipado através da utilização concomitante da oxigênio terapia hiperbárica. / The objectives were to evaluate the effect of GM1 ganglioside, hyperbaric oxygen, and both in combination, in the treatment of experimental spinal cord lesions in rats. Thirty-two Wistar rats with spinal cord lesions were divided into four groups: one group received GM1 ganglioside, one was submitted to hyperbaric oxygen therapy, the third received both treatments, and the fourth received no treatment (control). There were no significant differences between the groups in the histological analysis, for any of the variables (necrosis, hemorrhage, hyperemia, cystic degeneration, p > 0.06). Neither were there any significant differences in the comparison of left and right sides in the functional tests (p > 0.06 for all). No significant differences were found in the locomotor ratings, in the comparison of groups at 2 days, 7 days, 21 days and 28 days after the surgical procedure. However, in the evaluation on day 14, Group 3, which received the combined therapy, showed a significantly higher BBB score than the other groups (p = 0.015). In the evaluation on day 28, there was a trend to Group 1 (GM1) and 3 (combined therapy) showed a higher BBB score than the group 4 (control), but with no significance (p=0,057). In conclusion, the is a benefit in the use of GM1 ganglioside, but with no significance and the therapeutic effect of GM1 in locomotor evaluation of rats submitted to spinal cord lesion is anticipated by hyperbaric oxygen therapy.

A importância dada aos parâmetros de qualidade da água, principalmente nas últimas décadas justifica a realização desse trabalho, que investiga a relação de alguns parâmetros turbulentos com o coeficiente de reaeração, 'K IND.2', através de duas técnicas distintas de medida: o método ótico e a técnica fotográfica. O método ótico relaciona a intensidade de luz recebida por um diodo imerso na água com a velocidade vertical no ponto onde é realizada a medida; os dados coletados pelo método ótico constituem um sinal elétrico que contém a informação da deformação da superfície. A partir desse sinal determinam-se os seguintes parâmetros: valor RMS da tensão, função de autocorrelação, macroescala e espectro. Os resultados obtidos por esse método são funções temporais. O método fotográfico consiste em obter fotografias de partículas iluminadas sobre a superfície livre da água, com tempo de exposição conhecido. O método foi melhorado pela adição de dois disparos de flash, para permitir a determinação da variação da velocidade. As fotos são digitalizadas em um software gráfico e os valores obtidos são interpolados através do método Kriging de interpolação. O método fotográfico é uma função espacial. A partir do método fotográfico são determinados os seguintes parâmetros: valor RMS, função de autocorrelação e espectro. Os resultados obtidos permitem a comparação quantitativa entre as funções de autocorrelação e espectros, e a relação entre o coeficiente de reaeração, 'K IND.2' e o valor RMS obtidos pela sonda e pela foto / The importance given to the parameters of quality of the water, mainly in the last decades, it justifies the accomplishment of this work, that it investigates the relation of some turbulent parameters with the re-aeration coefficient, 'K IND.2', through two different techniques of measure: the optic method and the photographic technique. The optic method relates the intensity of the light received by a immersed diode in the water with the vertical speed at the point where the measure is accomplished; the data collected by the optic method are electric signs that contains the information of the deformation of the surface. Thereafter this signs, the following parameters are determined: RMS value of tension, self-correlation function, macro-scale and spectrum. The results obtained for this method they are temporal functions. The photographic method consists of obtaining pictures of illuminated particles on the free surface of the water, with time of exhibition known. The method was improved by addition of two shots of flashes, to allow the determination of the variation of the speed. The pictures, then, are digitized in a graphic software and the values obtained are interpolated through the Kriging interpolation method. The photographic method is a spatial function. With the photographic method may be determined the following parameters: RMS value, self-correlation function and spectrum. The results obtained may provide the quantitative comparison between the self-correlation function and spectrum; and also the relation between the re-aeration coefficient, 'K IND.2', and the RMS value, that are obtained through the probe and the picture

Ungefär hälften av Sveriges befolkning får idag sitt dricksvatten från grundvatten. Naturligt sker grundvattenbildning främst genom nederbörd, men under vissa förhållanden kan grundvatten också bildas av att ytvatten (t.ex. en sjö eller ett vattendrag) tränger in till grundvattnet. Grundvattenbildningen sker då under mättade förhållanden, det vill säga under grundvattenytan, vilket kan ha påverkan på grundvattnets kvalitet. Ytvatten innehåller naturligt höga halter av organiskt material som bryts ned av mikroorganismer som förbrukar syre under sin respiration. När nedbrytning sker under mättade förhållanden finns det risk för att syre förbrukas snabbare än vad det tillförs, då det inte finns någon kontakt med atmosfären. Det gör att organiskt material kan bli kvar längre vilket kan leda till syrefattiga förhållanden. Organiskt material kan försvåra reningsprocessen då det kan bidra med t.ex. färg och lukt. I syrefattiga miljöer finns det också risk för högre halter av järn och mangan vilka kan orsaka fällningar i ledningsnät, eller till färg och lukt. Det är därför önskvärt att ha sådan liten halt organiskt material som möjligt, samt låga järn och manganhalter. Utanför Borlänge i Dalarnas län öppnades förra året en ny grundvattentäkt som tillsammans med en äldre grundvattentäkt, Övre Tjärna, ska förse både Borlänge och Falun med dricksvatten. Då den är så pass ny är det lämpligt att undersöka förändringar i grundvattenkvaliteten då det, om de tillåts fortgå alltför länge, skulle kunna orsaka problem i framtiden. Syftet med den här rapporten är därför att bestämma hur driften av vattentäkterna kan komma att påverka grundvattenkvaliteten med avseende på syrenivå och halt organiskt material till följd av en ökad inträngning av ytvatten från Dalälven. Dessutom undersöktes om det skett förändringar i grundvattnets flödesriktning samt hur situationen kan se ut i framtiden. En tydlig inträngning av ytvatten och organiskt material kunde ses vid Övre Tjärnas vattentäkt. Vid Lennheden syntes inga tecken på en ökad inträngning efter driftstarten förra året, däremot syntes en förändring i grundvattnets flödesriktning som verkar ha skiftat riktning från sydostlig till nordvästlig. Syrehalten var förvånansvärt låg inom hela undersökningsområdet. Till följd av den låga syrenivån och halten organiskt material har halten av tvåvärt järn och tvåvärt mangan börjat öka. / Today, half of Sweden’s water supply comes from groundwater sources. Renewal of groundwater naturally happens most commonly through precipitation that seeps down to the groundwater table, but during special conditions renewal of groundwater through intrusion of surface water (e.g. river or lake) is possible. This will take place during saturated conditions, i.e. below the groundwater table, which will affect the quality of the groundwater. Surface water has a high content of organic matter, which will be degraded with the help of microorganisms. The microorganisms use oxygen during their respiration, and when the degradation takes place at saturated conditions the oxygen is being consumed at a higher rate than it is being added, since there is no contact with the atmosphere. This means that there is a risk that the organic matter will not degrade completely, which can cause problems in the drinking water plant, since organic matter can cause colour and smell to the water. Water with low oxygen content can also have higher concentrations of iron and manganese, which can lead to precipitation in pipes and to colour and smell as well. Last year, a new groundwater fed drinking water plant opened in Lennheden, situated northwest of Borlänge. It will, together with the old drinking water plant Övre Tjärna, supply both Borlänge and Falun with drinking water. Since it recently opened, it is suitable to examine possible changes in the groundwater quality, as it can cause problems in the future if the changes are not discovered in time. Both the drinking water plants are situated near the river Dalälven, where the intrusion of surface water is thought to have increased after the opening of the water plants. The aim of this study was therefore to determine how the operation of the two water plants will affect the groundwater quality, with regard to oxygenation and organic matter, due to the believed increased intrusion of surface water. In addition, possible changes in the groundwater flow directions were examined as well as how the situation can look like in the future. The results showed that there is a clear intrusion of surface water and increased organic content in the direction towards the old water plant, Övre Tjärna. No indications of increased intrusion due to the opening of Lennheden water plant could be seen, but a change in groundwater flow direction from southeast to northwest could be identified. The oxygen level was surprisingly low in the whole study area, which has lead to higher concentrations of iron and manganese in the groundwater.

This study has as main purpose to evaluate the influence of different color profiles on the cultivation related to temperature and dissolved oxygen concentration in the nutrient solution in the growing of rocket over two growing seasons in hydroponic system NFT. The experiment was conducted in the period of April to August 2012, in protected ambient counting with three production benches each comprised of eight profiles for the conduct of the plants evaluated, having four black and four white painted with plastic paint. The two colors of profile were arranged alternately and, to surround effect, a profile was installed on each edge of the bench. During the experiment, the temperature was recorded and the concentration of dissolved oxygen in the nutrient solution in the profiles three times per day, at 9:00, 15:00 and 21:00. In each reading recorded the temperature and concentration of oxygen at the beginning and end of two profiles of each color. For growth analysis, assessments were performed every four days in two growing seasons, autumn and winter, and the variables were evaluated: leaf dry matter, stem dry mass and root dry mass; plant height; root length; number of leaves and leaf area index. The results were analyzed separately and show that the different colors and profile stations modify the temperature and oxygen concentration of the nutrient solution. The black color profile increased the temperature of the circulating nutrient solution. Changes in temperature affected the concentration of dissolved oxygen in the nutrient solution. The different colors and seasons interfered with the growth of rocket. Plants grown in white profile showed higher leaf dry matter, stem dry mass and root dry mass, as well as increased root length and increased leaf area index. / O trabalho teve como objetivo avaliar a influência de diferentes cores de perfis de cultivo sobre a temperatura e concentração de oxigênio dissolvido na solução nutritiva no cultivo de rúcula ao longo de duas estações de cultivo em sistema hidropônico NFT. O experimento foi realizado no período de abril a agosto de 2012, em ambiente protegido contando com três bancadas de produção cada qual composta por oito perfis para a condução das plantas avaliadas sendo, quatro de cor preta e quatro pintados com tinta plástica branca. As duas cores de perfil foram dispostas alternadamente e, para efeito de bordadura foi instalado um perfil em cada borda da bancada. Durante a condução do experimento, foi registrada a temperatura e concentração de oxigênio dissolvido na solução nutritiva nos perfis três vezes por dia, sendo às 9:00h, 15:00h e 21:00h. Em cada leitura registrava-se a temperatura e concentração de oxigênio no início e final de dois perfis de cada cor. Para a análise de crescimento, as avaliações foram realizadas a cada quatro dias em duas estações de cultivo, outono e inverno, e as variáveis avaliadas foram: massa de folha seca, massa de caule seco e massa de raiz seca; altura de planta; comprimento de raiz; número de folhas e índice de área foliar. Os resultados obtidos foram analisados separadamente e demonstram que as diferentes cores de perfil e estações do ano modificaram a temperatura e concentração de oxigênio da solução nutritiva. A cor preta do perfil aumentou temperatura da solução nutritiva circulante. Mudanças na temperatura influenciaram na concentração de oxigênio dissolvido na solução nutritiva. As diferentes cores de perfil e estações do ano interferiram no crescimento da rúcula. As plantas cultivadas no perfil branco apresentaram maior massa de folha seca, massa de caule seco e massa de raiz seca, bem como maior comprimento de raiz e maior índice de área foliar.

Master of Science / Department of Kinesiology / Timothy I. Musch / Aged rats exhibit a decreased muscle microvascular O[subscript]2 partial pressure (PO[subcript]2mv) at rest as well as during contractions compared to young rats and this may contribute to their reduced exercise tolerance. Age-related reductions in nitric oxide (NO) bioavailability due, in part, to elevated reactive O[subscript]2 species (ROS) constrain muscle blood flow (Qm). Therefore, antioxidants may restore NO bioavailability, Qm and ameliorate the reduction in PO[subscript]2mv and hence the decrease in exercise tolerance seen in aged rats. PURPOSE: To test the hypothesis that antioxidants would elevate Qm at rest and during contractions and therefore PO[subscript]2mv in aged muscle. METHODS: PO[subscript]2mv and Qm were measured in the spinotrapezius while muscle oxygen consumption (VO[subscript]2m) was estimated in 20 anesthetized male Fisher 344 x Brown Norway hybrid (F344xBN) rats at rest and during 1 Hz contractions before and after antioxidant intravenous infusion (76mg/kg vitamin C and 52mg/kg tempol). Moreover, muscle force production was measured in a subset of animals. RESULTS: Before infusion, contractions invoked a biphasic PO[subscript]2mv that fell from 30.6 [plus or minus] 0.9 mmHg to a nadir of 16.8 [plus or minus] 1.2 mmHg with an 'undershoot' of 2.8 [plus or minus] 0.7 mmHg below the subsequent steady-state (19.7 [plus or minus] 1.2 mmHg). Antioxidants elevated baseline PO[subscript]2mv to 35.7 [plus or minus] 0.8 mmHg (P<0.05) and reduced or abolished the 'undershoot' (P<0.05) without changing the steady-state contracting PO[plus or minus]2mv. Antioxidants did not change Qm at rest but during contractions Qm was reduced from 157 [plus or minus] 28 to 91 [plus or minus] 15 ml min[superscript]-1 100g[superscript]-1 (P<0.05). Antioxidants produced no significant effect on VO[subscript]2m. However, antioxidant supplementation produced a 16.5% decrease (P<0.05) in muscle force production that occurred within the first contraction and remained throughout the duration of stimulation. In addition, the ratio of muscle force production to VO[subscript]2m (F/VO[subscript]2m) actually increased from 0.92 [plus or minus] 0.03 to 1.06 [plus or minus] 0.6 (P<0.05) following infusion of antioxidants. CONCLUSION: Antioxidant supplementation significantly alters the balance between muscle O[subscript]2 delivery and VO[subscript]2 at rest and during contractions, which modifies the microvascular PO[subscript]2mv profile. Specifically, antioxidants elevate PO[subscript]2mv, which improves the potential for diffusive blood-myocyte flux. This effect arises, in part, from the unanticipated fall in muscle force production consequent to antioxidant supplementation.

Litter-decay fungi have recently been shown to secrete heme-thiolate peroxygenases that oxidize various organic chemicals, but little is known about the physiological role or the mechanism of these enzymes. The aromatic peroxygenase of Agrocybe aegerita (AaeAPO) was purified and catalytically characterized. An overall reaction mechanism was proposed. The results show that AaeAPO catalyzed diverse H2O2-dependent monooxygenations (two-electron oxidations) including (a) the cleavage of aliphatic and aromatic ethers, (b) the regio- and enantioselective hydroxylation of aromatic compounds, (c) the stepwise oxygenation of benzylic compounds, (d) the N-dealkylation of secondary amines and (e) the dehalogenation of halogenated aliphatic compounds as well as typical peroxidase reactions (suggested to involve one-electron oxidation) such as (f) oxidation and polymerization of phenols and (g) halogenations. The enzyme failed to oxidize polymers such as polyethylene glycol (PEG). Mechanistic studies with several model substrates provided information about the reaction cycle of AaeAPO: (1) stoichiometry of tetrahydrofuran cleavage showed that the reaction was a two-electron oxidation that generated one aldehyde group and one alcohol group, yielding the ring-opened product 4-hydroxybutanal, (2) steady-state kinetics results with methyl 3,4-dimethoxybenzyl ether, which was oxidized to 3,4-dimethoxybenzaldehyde, gave parallel double reciprocal plots suggestive of a ping-pong mechanism, (3) the cleavage of methyl 4-nitrobenzyl ether, the hydroxylation of aromatics such as diclofenac and nitrophenol and the oxygenation of benzylic compounds, resulted in incorporation of 18O into the reaction product in the presence of H218O2, and (4) the demethylation of 1-methoxy-4-trideuteromethoxybenzene showed an distinct observed intramolecular deuterium isotope effect. These results support a mechanism similar to that envisaged for the peroxygenase activity of P450s in which the enzyme heme is oxidized by H2O2 to give an iron species that carries one of the peroxide oxygen. This intermediate then abstracts a hydrogen from the substrate, which is followed by rebound of an •OH equivalent to produce the monooxygenated reaction product (hydrogen abstraction and oxygen rebound mechanism). AaeAPO may accordingly have a role in the biodegradation of natural and anthropogenic low molecular weight compounds in soils and plant litter. Moreover, the results raise the possibility that fungal peroxygenases may be useful for versatile, cost-effective, and scalable syntheses of drug metabolites and herbicide precursors. / Die Peroxygenase des Südlichen Ackerling (Agrocybe aegerita, AaeAPO) wurde gereinigt, ihr Katalysepotential ermittelt und ein allgemeiner Reaktionsmechanismus postuliert. Die AaeAPO katalysiert sowohl H2O2-abhängige Monooxygenierungen (Zwei-Elektron Oxidationen) wie (a) die Spaltung aliphatischer und aromatischer Ether, (b) die regio- und enantioselektive Hydroxylierung von Aromaten, (c) die schrittweise Monooxygenierung von Toluolderivaten, (d) die N-Dealkylierung sekundärer Amine und (e) die Dehalogenierung chlorierter Aliphaten als auch typische Reaktionen bekannter Peroxidasen (vermutlich Ein-Elektron-Oxidation) unter anderem (f) die Oxidation/ Polymerisierung von Phenolen und (g) die Halogenierung von Aromaten. Polymere Verbindungen wie Polyethylenglycol (PEG) werden nicht oxidiert. Mechanistische Untersuchungen zur Etherspaltung am Beispiel der AaeAPO haben Einblick in den generellen Reaktionsmechanismus dieses neuen Enzymtyps ermöglicht: (1) die Stöchiometrie der Spaltung von Tetrahydrofuran entspricht der einer zwei-Elektron-Oxidation, (2) die Spaltung von Methyl-3,4-Dimethoxybenzylether zu 4-Dimethoxybenzaldehyd und Methanol ergaben parallele Verläufe für die ermittelten Ausgleichsgeraden in der doppelt reziproken Darstellung, was einem „Ping-Pong“-Reaktionsmechanismus entspricht (3) die Monooxygenierungen haben stets den Einbau eines aus dem Peroxid (H2O2) stammenden Sauerstoffatoms in das Produkt zur Folge, (4) die O-Dealkylierung von 1-Methoxy-4-Trideuterummethoxybenzol zeigt einen ausgeprägten Deuterium Isotopen Effekt, was auf die primäre Abspaltung eines Wasserstoffatoms vom Substratmolekül hindeutet. Demnach verläuft die Peroxygenase-katalysierte Monooxygenierung über Wasserstoffabstraktion und eine unmittelbar anschließende Sauerstoffrückbindung (hydrogen abstraction - oxygen rebound mechanism). Diese Reaktionsabfolge ähnelt dem sogenannten peroxide "shunt" pathway, der von einer Reihe Cytochrom-P450-abhängiger Monooxygenasen her bekannt ist. Die physiologische Funktion der AaeAPO besteht möglicherweise in der extrazellulären Transformation und Detoxifikation niedermolekularer Pflanzeninhaltsstoffe, mikrobieller Metabolite und anthropogener Xenobiotika. Aufgrund der Stabilität und Unabhängigkeit der AaeAPO von teuren Kofaktoren ergeben sich vielversprechende biotechnologische Möglichkeiten zum Einsatz isolierter Biokatalysatoren in selektiven (bio)chemischen Synthesen monooxygenierter Metabolite.

To counteract one of the most urgent environmental issues in the Baltic Sea; eutrophication, excessivealgal blooms and hypoxia, a proposal to use wave energy to pump oxygen-rich surface water towardsthe sea bottom is investigated. Proposals have suggested that 100 kg of oxygen per second is needed tooxygenate bottom water and enhance binding of phosphorus to bottom sediments. This corresponds to 10 000 m3/s of oxygen-rich surface water. This thesis investigates a wave-powered device to facilitatethis oxygen ux. Results give expected water flow rates between 0.15 - 0.40 m3/s and meter breakwater.The mean specic wave power for the analyzed wave data is calculated to be between 3 - 4 kW/m wavecrest and the median to 1 kW/m. This study indicate, however, that the energy uxes in the BalticProper are signicantly higher. The study gives that the wave climate of the Baltic Sea is suffciently intense to facilitate vertical pumping with a feasible number of breakwaters. A full-scale implementationin the Baltic Sea would require some 300 to 1 200 oating breakwaters of a length of 50 m each. Thetotal cost is roughly estimated to 170 - 680 million EURO. The study also concludes that the interleavingof surface water should be constrained to a relatively small vertical distance from the outlet depth(20 - 30 m) and not stir up deep water to the surface. Wave modelling for the proposed pilot locationKanholmsfjärden indicate that this bay is not large enough to permanently produce a favorable waveclimate. It is, however, still an interesting location consistently to its vicinity to Stockholm and relativelylong measurement series.