54 resultados para DTP


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Serogroup B Neisseria meningitidis (MenB) is a major cause of invasive disease in early childhood worldwide. The only MenB vaccine available in Brazil was produced in Cuba and has shown unsatisfactory efficacy when used to immunize millions of children in Brazil. In the present study, we compared the specific functional antibody responses evoked by the Cuban MenB vaccine with a standard vaccine against diphtheria (DTP: diphtheria, tetanus, pertussis) after primary immunization and boosting of mice. The peak of bactericidal and opsonic antibody titers to MenB and of neutralizing antibodies to diphtheria toxoid (DT) was reached after triple immunization with the MenB vaccine or DTP vaccine, respectively. However, 4 months after immunization, protective DT antibody levels were present in all DTP-vaccinated mice but in only 20% of the mice immunized against MenB. After 6 months of primary immunization, about 70% of animals still had protective neutralizing DT antibodies, but none had significant bactericidal antibodies to MenB. The booster doses of DTP or MenB vaccines produced a significant antibody recall response, suggesting that both vaccines were able to generate and maintain memory B cells during the period studied (6 months post-triple immunization). Therefore, due to the short duration of serological memory induced by the MenB vaccine (VA-MENGOC-BC® vaccine), its use should be restricted to outbreaks of meningococcal disease.

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In this venture three distinct class of catalysts such as, pillared clays and transition metal loaded pillared clays , porous clay heterostructures and their transition metal loaded analogues and DTP supported on porous clay heterostructures etc. were prepared and characterized by various physico chemical methods. The catalytic activities of prepared catalysts were comparatively evaluated for the industrially important alkylation, acetalization and oxidation reactions.The general conclusions drawn from the present investigation are  Zirconium, iron - aluminium pillared clays were synthesized by ion exchange method and zirconium-silicon porous heterostructures were Summary and conclusions 259 prepared by intergallery template method. Transition metals were loaded in PILCs and PCHs by wet impregnation method.  Textural and acidic properties of the clays were modified by pillaring and post pillaring modifications.  The shift in 2θ value to lower range and increase in d (001) spacing indicate the success of pillaring process.  Surface area, pore volume, average pore size etc. increased dramatically as a result of pillaring process.  Porous clay heterostructures have higher surface area, pore volume, average pore diameter and narrow pore size distribution than that of pillared clays.  The IR spectrum of PILCs and PCHs are in accordance with literature without much variation compared to parent montmorillonite which indicate that basic clay structure is retained even after modification.  The silicon NMR of PCHs materials have intense peaks corresponding to Q4 environment which indicate that mesoporous silica is incorporated between clay layers.  Thermo gravimetric analysis showed that thermal stability is improved after the pillaring process. PCH materials have higher thermal stability than PILCs.  In metal loaded pillared clays, up to 5% metal species were uniformly dispersed (with the exception of Ni) as evident from XRD and TPR analysis. Chapter 9 260  Impregnation of transition metals in PILCs and PCHs enhanced acidity of catalysts as evident from TPD of ammonia and cumene cracking reactions.  For porous clay heterostructures the acidic sites have major contribution from weak and medium acid sites which can be related to the Bronsted sites as evident from TPD of ammonia.  Pillared clays got more Lewis acidity than PCHs as inferred from α- methyl styrene selectivity in cumene cracking reaction.  SEM images show that layer structure is preserved even after modification. Worm hole like morphology is observed in TEM image of PCHs materials  In ZrSiPCHS, Zr exists as Zr 4+ and is incorporated to silica pillars in the intergallary of clay layers as evident from XPS analysis.  In copper loaded zirconium pillared clays, copper exists as isolated species with +2 oxidation state at lower loading. At higher loading, Cu exists as clusters as evident from reduction peak at higher temperatures in TPR.  In vanadium incorporated PILCs and PCHs, vanadium exist as isolated V5+ in tetrahedral coordination which is confirmed from TPR and UVVis DRS analysis.  In cobalt loaded PCHs, cobalt exists as CoO with 2+ oxidation state as confirmed from XPS.  Cerium incorporated iron aluminium pillared clay was found to be the best catalyst for the hydroxylation of phenol in aqueous media due to the additional surface area provided by ceria mesopores and its redox properties. Summary and conclusions 261  Cobalt loaded zirconium porous clay heterostructures were found to be promising catalyst for the tertiary butylation of phenol due to higher surface area and acidic properties.  Copper loaded pillared clays were found to be good catalyst for the direct hydroxylation of benzene to phenol.  Vanadium loaded PCHs catalysts were found to be efficient catalysts for oxidation of benzyl alcohol.  DTP was firmly fixed on the mesoporous channels of PCHs by Direct method and functionalization method.  DTP supported PCHs catalyst were found to be good catalyst for acetalization of cyclohexanone with more than 90% conversion.

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Research on autonomous intelligent systems has focused on how robots can robustly carry out missions in uncertain and harsh environments with very little or no human intervention. Robotic execution languages such as RAPs, ESL, and TDL improve robustness by managing functionally redundant procedures for achieving goals. The model-based programming approach extends this by guaranteeing correctness of execution through pre-planning of non-deterministic timed threads of activities. Executing model-based programs effectively on distributed autonomous platforms requires distributing this pre-planning process. This thesis presents a distributed planner for modelbased programs whose planning and execution is distributed among agents with widely varying levels of processor power and memory resources. We make two key contributions. First, we reformulate a model-based program, which describes cooperative activities, into a hierarchical dynamic simple temporal network. This enables efficient distributed coordination of robots and supports deployment on heterogeneous robots. Second, we introduce a distributed temporal planner, called DTP, which solves hierarchical dynamic simple temporal networks with the assistance of the distributed Bellman-Ford shortest path algorithm. The implementation of DTP has been demonstrated successfully on a wide range of randomly generated examples and on a pursuer-evader challenge problem in simulation.

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We estimated the sensitivity, i.e., the proportion of all cases of adverse events following immunization (AEFIs) reported to the Brazilian passive surveillance for adverse events following immunization (PSAEFI) with the diphtheria-tetanus-whole-cell pertussis-Haemophilus influenzae type b (DTwP/Hib) vaccine, as well as investigating factors associated with AEFIs reporting. During 2003-2004, 8303 AEFIs associated with DTwP-Hib were reported; hypotonic-hyporesponsive episodes (HHEs), fever and convulsions being the most common. Cure without sequel was achieved in 98.4% of the cases. The mean sensitivity of the PSAEFI was 22.3% and 31.6%, respectively, for HHE and convulsions, varying widely among states. Reporting rates correlated positively with the Human Development Index and coverage of adequate prenatal care, correlating negatively with infant mortality rates. Quality of life indicators and the degree of organization of health services are associated with greater PSAEFI sensitivity. In addition to consistently describing the principal AEFIs, PSAEFI showed the DTwP/Hib vaccine to be safe and allayed public fears related to its use. (C) 2010 Elsevier Ltd. All rights reserved.

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O comportamento de calcários gaúchos, como dessulfurantes, foi avaliado levando-se em consideração a influência das características estruturais dos calcinados e de seus precursores. Os materiais, na faixa granulométrica de 53-62µm, foram calcinados em uma termobalança em atmosfera de N2 (100%) ou de mistura N2 (85,2%) + CO2 (14,8%) e posteriormente, submetidos a mistura oxidante contendo dióxido de enxofre. As distribuições de tamanhos de poros (DTP) dos calcinados, mostraram-se dependentes da atmosfera de calcinação e do raio de grão do calcário precursor. A ordem de reatividade, estabelecida pelos calcinados estudados neste trabalho, não apresentou relação com a consideração de uma DTP ótima (maioria de poros acima de 50Å), não sendo portanto este critério válido para seleção de dessulfurantes. Para os calcinados de uma mesma amostra, obteve-se uma relação direta entre tamanho de grão do CaO (área superficial) e reatividade, sendo as trajetórias de reação definidas de maneira combinada entre as suas distribuições de tamanhos de poros e a forma como os poros estão localizados e conectados na estrutura. Entre materiais diferentes, calcinados sob as mesmas condições e que apresentam as mesmas características físicas e de distribuição, as trajetórias de reação foram bastante distintas, demonstrando que essas semelhanças físicas não correspondem a uma mesma capacidade de reação ao longo do tempo. Isto salientou uma possível influência das características intrínsecas de cada material, relacionadas à localização e conexão dos poros na estrutura, em sua capacidade dessulfurante. Entre os calcinados com semelhanças em suas DTP e propriedades físicas, tornou-se possível relacionar a ordem de reatividade ao raio de grão do calcário precursor (determinante da localização e da forma de conexão dos poros na estrutura), sendo os calcinados de precursores de menor raio de grão os mais reativos.

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This thesis aimed to assess the increase in solubility of simvastatin (SINV) with solid dispersions using techniques such as kneading (MA), co-solvent evaporation (ES), melting carrier (FC) and spray dryer (SD). Soluplus (SOL), PEG 6000 (PEG), PVP K-30 (PVP) e sodium lauryl sulphate (LSS) were used as carriers. The solid dispersions containing PEG [PEG-2(SD)], Soluplus [SOL-2(MA)] and sodium lauryl sulphate [LSS-2(ES)] were presented with a greater increase in solubility (5.02, 5.60 and 5.43 times respectively); analyses by ANOVA between the three groups did not present significant difference (p<0.05). In the phase solubility study, the calculation of the Gibbs free energy (ΔG) revealed that the spontaneity of solubilisation of SINV occurred in the order SOL>PEG >PVP 75%>LSS, always 80%. The phase diagrams of PEG and LSS presented solubilization stoichiometry of type 1:1 (type AL). The diagrams with PVP and SOL tend to 1:2 stoichiometry (type AL + AP). The stability coefficients (Ks) of the phase diagrams revealed that the most stable reactions occurred with LSS and PVP. The solid dispersions were characterized by Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), particle size distribution (PSD), near-infrared spectroscopy imaging (NIR-CI) and X-ray diffraction of the powder using the Topas software (PDRX-TOPAS). The solid dispersion PEG-2(SD) presented the greatest homogeneity and the lowest degree of crystallinity (18.2%). The accelerated stability study revealed that the solid dispersions are less stable than SINV, with PEG-2(SD) being the least stable, confirmed by FTIR and DSC. The analyses by PDRX-TOPAS revealed the amorphous character of the dispersions and the mechanism of increasing solubility

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The sector of civil construction is strongly related to the red ceramic industry. This sector uses clay as raw material for manufacturing of various products such as ceramic plates. In this study, two types of clay called clay 1 and clay 2 were collected on deposit in Ielmo Marinho city (RN) and then characterized by thermogravimetric analysis (TG/DTG), differential thermal analysis (DTA), X-ray diffraction (XRD), X-ray fluorescence (XRF), rational analysis and particle size distribution and dilatometric analyses. Ceramic plates were manufactured by uniaxial pressing and by extrusion. The plates obtained by pressing were produced from the four formulations called 1, 2, 3 and 4, which presented, respectively, the following proportions by mass: 66.5% clay 1 and 33.5% clay 2, 50% clay 1 and 50% clay 2, 33.5% clay 1 and 66.5% clay 2, 25% clay 1 and 75% clay 2. After firing at 850, 950 and 1050 °C with heating rate of 10 °C/min and soaking time of 30 minutes, the following technological properties were determined: linear firing shrinkage, water absorption, apparent porosity, apparent specific mass and tensile strength (3 points). The formulation containing 25% clay 1 produced plates with most satisfactory results of water absorption and mechanical resistance, because of that it was chosen for manufacturing plates by extrusion. A single firing cycle was established for these plates, which took place as follow: heating rate of 2 °C/min up to 600 ºC with soaking time of 60 minutes, followed by heating using the same rate up to 1050 ºC with soaking time of 30 minutes. After this cycle, the same technological properties investigated in the plates obtained by pressing were determined. The results indicate (according to NRB 13818/1997) that the plates obtained by pressing from the mixture containing 25 wt% clay 1, after firing at 1050 °C, reach the specifications for semi-porous coating (BIIb). On the other hand, the plates obtained by extrusion were classified as semi-stoneware (group AIIa)

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Catalytic processes are widely present in everyday life. This results in large number of studies seeking materials that may combine the low cost catalytic efficiency. Based on this assumption, the clays have long been used as catalysts, with its huge availability, diversity and possibility of improving their properties from structural changes, primarily responsible for this great use. Among the natural clays, vermiculite due to their characteristic properties (high cation exchange capacity and expansion), is suitable for various applications including as catalysts and catalyst supports. In this work, the acid leaching of clay vermiculite was performed, coming from Santa Luzia-PB, with nitric acid (2, 3 and 4 mol / L) and subsequent calcination of the materials obtained. The materials were named as Vx/400, where x is the acid concentration employed and 400 used in calcination temperature. The effectiveness of changes made was determined by XRD techniques, FT-IR, EDS, TG/DTG, nitrogen physisorption and DTP of n-butylamine. Acid leaching has improved some properties of the clay - specific area and acidity - but the control of the acid concentration used is of vital importance, since the highest concentration caused the partial destruction of vermiculite entailing a decline in their properties. For analysis of the catalytic activity of the modified clay was made a comparative study with the SBA -15 mesoporous materials, synthesized via hydrothermal method, using the pyrolysis of low density polyethylene (LDPE). The results showed that the acid plays a fundamental role in the conversion of the polymer into smaller molecules, the material V3/400 was more selective for the source monomer (ethylene) due to their increased acidity, which promotes more breaks bonds in the polymeric chain, while materials and V0/400 V2/400, lower acidity, showed higher selectivity to light hydrocarbons, the range of fuel (41.96 and 41.23%, respectively), due to less breakage and secondary condensation reactions chains; already V4/400 SBA-15/550 and resulted in lower percentages of light hydrocarbons and the partial destruction of the structure and low acidity, respectively, responsible for the inefficiency of materials

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O principal objetivo deste trabalho é investigar teóricamente as propriedades eletrônicas e óticas de compostos orgânicos em ambiente líquido. A compreensão das interações em sistemas líquidos é muito importante para a descrição de fenômenos em muitas partes da ciência, como Física, Química, Biologia e Materiais, bem como no desenvolvimento de materiais óticos. As flutuações térmicas fazem que inumaram das configurações para os líquidos possam ser gerados. Esta é a razão do comportamento estatístico observado em sistemas líquidos. Considerando estas dificuldades, o tratamento sequencial Monte Carlo / Mecânica Quântica (SMC/QM) é usado neste trabalho. Neste procedimento, a estrutura líquida é gerada primeiramente por simulações clássicas de MC e mais tarde, somente a parte mais importante do sistema é tratada com mecânica quântica. Usando o procedimento acima, os propriedades do quantum o pirazine dimethyl do thiene Methyl da laranja (MO) e do O 2,3-dimetil tieno[3,4-b] pirazina (DTP) foram investigados. O MO é um conhecido indicador de pH e pode ser encontrado sob circunstâncias básicas e acidas. Suas geometrias de mínima energia foram obtidas mediante a Teoria do Funcional da Densidade pelo funcional B3LYP, sendo o sistema descrito pelas bases de Pople com uma função de polarização (6-31G*). Para obter as propriedades médias dos observaveis, cálculos de química quântica foram executados dentro da aproximação semi-empírica de INDO/S-CI. Com respeito ao espectro de absorção, os dados experimentais existentes na literatura científica reportam a existência de uma larga banda localizada na região de baixas energias, mais precisamente entre 400 e 600 nm. Nossos resultados teóricos para a forma alcalina mostram uma transição intensa transição π → π* aproximadamente à 432.4 ± 0.03 nm e, sob condições ácidas, esta transição aparece aproximadamente à 507.4 ± 0.12, 496.4 ± 0.28 ou 545.3 ± 0.10 nm, dependendo da estrutura, mostrando bom acordo com resultados experimentais. O DTP é um sistema particular usado na produção de polímeros de baixo gap. Suas propriedades elétricas e óticas foram obtidas através de um novo procedimento conhecido por Configuração Eletrostática Média do Solvent (ASEC). O procedimento ASEC inclui moléculas do solvente como cargas pontuais e permite o obtenção das quantidades quânticas executando somente poucos cálculos de mecânica quântica. Para o DTP, usando a teoria das perturbações de segunda ordem Mφller-Plesset (MP2) e o conjunto de bases aug-cc-pVDZ, a convergência do momento de dipolo foi alcançada com apenas quatro cálculos de mecânica quântica à 1.16 D, apresentando um aumento de 42% quando comparado ao dipolo isolado. O polarizabilidade corresponde à outra característica elétrica que pôde ser medida. Considerando o mesmo nível empregado ao cálculo do dipolo, o valor médio 132.7 a30 foi observado. A região de mais baixas da energias do espectro de absorption foi investigada também atravé de procedimento de ASEC usando ambos as aproximações, semi-empírico e DFT. Esta região de absorção é motivo de conclusões contraditórias com relação à natureza das transições n → π* e π → π*. Nossos resultados mostram que realmente que essas excitações são realmente observadas simultanemente podendo sobrepôr-se. Como exemplo, nossos resultados para DFT, encontrados usando o funcional B3LYP nos mostra que estas transições aparecem aproximadamente à 360.6 e 351.1 nm.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The goal of this article is to introduce the Gestalt Psychology as an alternative approach to be applied in the present pedagogic practice of education of brasilian youngsters and adults (EYA) starting with researchs done to introduce the short hystory of EYA in Brazil demonstrating its discussion among us since a long time, at least, since the transition from the Imperial to the Republican period, wich comes from the end of the XIX Century up to the begining of the XX Century. This history also shows different organizational moves of EYA already developed in this country in the public and private fields, as well its present reality in the large spectrum of brazilian education. Right after, it approachs and explains shortly the rising of the theory and the main concepts and laws of the Gestalt Psychology in an atempt to demonstrate and enlight its proposed applicability. The author finishs the article introducing the possible relation among concepts, Gestalt laws and education of youngsters and adults to be applyed day by day in the classroom to optimise the process of teaching and learning in the Education of Youngsters and Adults in Brazil.

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INTRODUÇÃO: As infecções de corrente sanguínea relacionadas com cateter (ICSRCs) apresentam impacto significativo na morbidade e na mortalidade de pacientes internados, além de elevar custos hospitalares. A utilização de equipamentos automatizados no processamento de hemoculturas gerou uma alternativa para diagnóstico de ICSRC por meio da análise da diferença de tempo de positividade (DTP) entre hemoculturas pareadas (coletadas simultaneamente) de sangue periférico e sangue de cateter. Um diagnóstico acurado e rápido dessas infecções pode otimizar as condutas clínicas e terapêuticas, poupando a retirada precoce dos cateteres. OBJETIVOS: Avaliar na rotina a DTP como ferramenta auxiliar no diagnóstico de ICSRC e determinar os principais microrganismos isolados. MÉTODOS: Foram avaliadas retrospectivamente hemoculturas coletadas no complexo do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HC/FMUSP) de maio a agosto de 2008. Somente amostras que apresentaram DTP maior que 120 minutos foram consideradas possíveis ICSRCs pelo critério laboratorial. RESULTADOS: A seção processou 11.017 hemoculturas aeróbias durante o período de estudo; somente 5% foram coletadas de forma pareada. Destas, 148 (28%) foram positivas, sendo 9% com crescimento somente em sangue periférico, 41% somente em sangue de cateter e 50% em ambas as amostras com 88% de homologia de microrganismos identificados. A DTP apresentou valores acima de 120 minutos em 50% dos casos e os microrganismos mais isolados foram Staphylococcus aureus (22%), Candida spp. (18%), Klebsiella spp. (7%) e Enterobacter spp. (7%). CONCLUSÃO: A determinação da DTP como ferramenta auxiliar no diagnóstico de ICSRC é viável e fácil de ser executada em laboratórios de rotina com automação, porém o processo de coleta das amostras pareadas deve ser rigidamente padronizado.

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Objective: to discuss the current PAHO recommendation that does not support the substitution of traditional cellular DTP vaccine by acellular DTP, and the role of mutations, in humans, as the main cause of rare adverse events, such as epileptic-like convulsions, triggered by pertussis vaccine. Data review: the main components related to toxic effects of cellular pertussis vaccines are the lipopolysaccharide of bacterial cell wall and pertussis toxin. The removal of part of lipopolysaccharide layer has allowed the creation of a safer cellular pertussis vaccine, with costs comparable to the traditional cellular vaccine, and which may be a substitute for the acellular vaccine. Conclusion: The new methodology introduced by Instituto Butantan allows for the development of a new safer pertussis vaccine with low LPS content (Plow), and the use of the lipopolysaccharide obtained in the process in the production of monophosphoryl lipid A. This component has shown potent adjuvant effect when administered together with influenza inactivated vaccine, making possible to reduce the antigen dose, enhancing the production capacity and lowering costs.

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Die optische Eigenschaften sowie der Oberflächenverstärkungseffekt von rauen Metalloberflächen sowie Nanopartikeln wurden intensiv für den infraroten Bereich des Spektrums in der Literatur diskutiert. Für die Präparation solcher Oberflächen gibt es prinzipiell zwei verschiedene Strategien, zum einen können die Nanopartikel zuerst ex-situ synthetisiert werden, der zweite Ansatz beruht darauf, dass die Nanopartikel in-situ hergestellt und aufgewachsen werden. Hierbei wurden beide Ansätze ausgetestet, dabei stellte sich heraus, dass man nur mittels der in-situ Synthese der Goldnanopartikel in der Lage ist nanostrukturierte Oberflächen zu erhalten, welche elektronisch leitfähig sind, nicht zu rau sind, um eine Membranbildung zu ermöglichen und gleichzeitig einen optimalen Oberflächenverstärkungseffekt zeigen. Obwohl keine ideale Form der Nanopartikel mittels der in-situ Synthese erhalten werden können, verhalten sich diese dennoch entsprechend der Theorie des Oberflächenverstärkungseffekts. Optimierungen der Form und Grösse der Nanopartikel führten in dieser Arbeit zu einer Optimierung des Verstärkungseffekts. Solche optimierten Oberflächen konnten einfach reproduziert werden und zeichnen sich durch eine hohe Stabilität aus. Der so erhaltene Oberflächenverstärkungseffekt beträgt absolut 128 verglichen mit dem belegten ATR-Kristall ohne Nanopartikel oder etwa 6 mal, verglichen mit der Oberfläche, die bis jetzt auch in unserer Gruppe verwendet wurde. Daher können nun Spektren erhalten werden, welche ein deutlich besseres Signal zu Rauschverhältnis (SNR) aufweisen, was die Auswertung und Bearbeitung der erhaltenen Spektren deutlich vereinfacht und verkürzt.rnNach der Optimierung der verwendeten Metalloberfläche und der verwendeten Messparameter am Beispiel von Cytochrom C wurde nun an der Oberflächenbelegung der deutlich größeren Cytochrom c Oxidase gearbeitet. Hierfür wurde der DTNTA-Linker ex-situ synthetisiert. Anschließend wurden gemischte Monolagen (self assembeld monolayers) aus DTNTA und DTP hergestellt. Die NTA-Funktionalität ist für die Anbindung der CcO mit der his-tag Technologie verantwortlich. Die Kriterien für eine optimale Linkerkonzentration waren die elektrischen Parameter der Schicht vor und nach Rekonstitution in eine Lipidmembran, sowie Elektronentransferraten bestimmt durch elektrochemische Messungen. Erst mit diesem optimierten System, welches zuverlässig und reproduzierbar funktioniert, konnten weitere Messungen an der CcO begonnen werden. Aus elektrochemischen Messungen war bekannt, dass die CcO durch direkten Elektronentransfer unter Sauerstoffsättigung in einen aktivierten Zustand überführt werden kann. Dieser aktivierte Zustand zeichnet sich durch eine Verschiebung der Redoxpotentiale um etwa 400mV gegenüber dem aus Gleichgewichts-Titrationen bekannten Redoxpotential aus. Durch SEIRAS konnte festgestellt werden, dass die Reduktion bzw. Oxidation aller Redoxzentren tatsächlich bei den in der Cyclovoltammetrie gemessenen Potentialen erfolgt. Außerdem ergaben die SEIRA-Spektren, dass durch direkten Elektronentransfer gravierende Konformationsänderungen innerhalb des Proteins stattfinden. rnBisher war man davon ausgegangen, aufgrund des Elektronentransfers mittels Mediatoren, dass nur minimale Konformationsänderungen beteiligt sind. Vor allem konnte erstmaligrnder aktivierte und nicht aktivierte Zustand der Cytochrom c Oxidase spektroskopisch nachweisen werden.rn

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High concentrations of fluoride naturally occurring in the ground water in the Arusha region of Tanzania cause dental, skeletal and non-skeletal fluorosis in up to 90% of the region’s population [1]. Symptoms of this incurable but completely preventable disease include brittle, discolored teeth, malformed bones and stiff and swollen joints. The consumption of high fluoride water has also been proven to cause headaches and insomnia [2] and adversely affect the development of children’s intelligence [3, 4]. Despite the fact that this array of symptoms may significantly impact a society’s development and the citizens’ ability to perform work and enjoy a reasonable quality of life, little is offered in the Arusha region in the form of solutions for the poor, those hardest hit by the problem. Multiple defluoridation technologies do exist, yet none are successfully reaching the Tanzanian public. This report takes a closer look at the efforts of one local organization, the Defluoridation Technology Project (DTP), to address the region’s fluorosis problem through the production and dissemination of bone char defluoridation filters, an appropriate technology solution that is proven to work. The goal of this research is to improve the sustainability of DTP’s operations and help them reach a wider range of clients so that they may reduce the occurrence of fluorosis more effectively. This was done first through laboratory testing of current products. Results of this testing show a wide range in uptake capacity across batches of bone char emphasizing the need to modify kiln design in order to produce a more consistent and high quality product. The issue of filter dissemination was addressed through the development of a multi-level, customerfunded business model promoting the availability of filters to Tanzanians of all socioeconomic levels. Central to this model is the recommendation to focus on community managed, institutional sized filters in order to make fluoride free water available to lower income clients and to increase Tanzanian involvement at the management level.