O autor estudou comparativamente, em coelhos, enxertos autólogos retirados do crânio e da crista ilíaca. Os animais foram divididos em dois lotes, crânio e crista ilíaca e a seguir distribuídos em três grupos diferentes, de acordo com o tempo de incorporação do enxerto ósseo. Foram correlacionados as medidas das dimensões e peso do enxerto com os achados histológicos realizados após o sacrifício do animal. O autor observou que o enxerto autólogo de crista ilíaca apresentou maior reabsorção que o de crânio aos sessenta dias. O enxerto autólogo de crânio iniciou a formação óssea mais precocemente que o enxerto de crista ilíaca / The author compared cranial and iliac crest autogenous bone grafts using an experimental model in rabbits. 57 animals were studied and divided in three different groups, according with the time of evaluation, of the bone graft, 18, 30 and 60 days after the first procedure. Before being positioned on the nasal bone and fixed with a screw, the bone grafts were measured and weighted. The same measures were done at the time of removal of the bone graft and all these datas were correlated with the information achieved with histomorphometric parameters of osteogenesis (bone volume, osteoid volume, osteoid surface, osteoblastic surface and osteoid thickness) and of bone resorption (osteoclastic surface and resorption surface). The author concluded: the relation final wight/inicial weight in the cranial bone grafts was greater than in the iliac crest bone grafts; the osteogenesis was smaller on the 18th day in the iliac crest bone grafts group than the control group; the osteogenesis was greater in the cranial bone grafts group than the iliac crest bone grafts group on the 18th and 30th day after bone grafting; the bone resorption was greater in the iliac crest bone grafts group than the cranial bone grafts group after 60 days; the presence of superficial osteogenesis was increased in the cranial bone grafts.

Os vasos de fino calibre apresentam maior risco para reestenose e revascularização da lesão alvo. Limitações relacionadas com a navegabilidade dos sistemas de dilatação por balão e menor capacidade de acomodação da neoíntima podem contribuir para isto. O stent autoexpansível de nitinol Sparrow® dedicado a vaso de calibre < 2,75 mm, resultou num conjunto com perfil de um fio-guia 0,014\". Testado na forma de stent de metal puro no estudo CARE I, revelou-se seguro e eficaz em vasos de fino calibre. Este estudo avaliou, de forma pioneira, o despenho de um stent autoexpansível farmacológico neste cenário. O objetivo primário foi comparar a perda luminal tardia no vaso-alvo pela angiografia coronária quantitativa ao final de oito meses, entre os stents Sparrow® farmacológico e não farmacológico, em coronárias com diâmetro de referência < 2,75 mm. Casuística e métodos: Os pacientes foram randomizados de forma prospectiva em dois grupos para procedimento de angioplastia: um grupo com o emprego o stent Sparrow® farmacológico (sirolimus), e ou outro grupo com o stent Sparrow® na versão não farmacológica. Análise pela angiografia coronária quantitativa foi realizada imediatamente antes e após o procedimento e aos oito meses, com seguimento clínico de 24 meses. Foi utilizado o programa IBM SPSS Statistics® para análise estatística e foi considerado nível de significância de 5% e poder de 80% para o cálculo do tamanho da amostra. Resultados: 24 pacientes foram randomizados, 12 no grupo com stent farmacológico Sparrow® e 12 no grupo com a versão não farmacológica. Na avaliação angiográfica aos oito meses verificou-se significativa redução de perda luminal tardia no grupo com o stent farmacológico Sparrow® em comparação com grupo com a versão não farmacológica (0,25 + 0,16 mm versus 0,97 + 0,76 mm, p = 0,008, IC 95% de -1,19 ; -0,22). No seguimento clínico de 12 meses, não foram observados eventos cardíacos adversos maiores (morte, infarto ou necessidade de revascularização do vaso alvo) no grupo com stent farmacológico. Não ocorreu trombose intrastent. Conclusão: Em pacientes submetidos à angioplastia transluminal percutânea em artérias coronárias com diâmetro de referência < 2,75 mm, o emprego do stent farmacológico autoexpansível Sparrow®, em comparação com a versão não farmacológica do mesmo stent, resultou em significativa redução de perda luminal tardia, sem ocorrência de eventos clínicos que deponham contra a segurança do dispositivo pesquisado. / Small vessels represent a group with high risk for restenosis and target lesion revascularization. Limitations associated with navigability of balloon dilation systems and less accommodating of the neointima may contribute to this. The self-expanding Sparrow® stent system dedicated to the vessel size <2.75 mm resulted in a profile similar to a 0.014\" guide wire angioplasty. Tested as bare metal stent in the CARE trial I, the Sparrow® stent system has proved to be safe and effective in small vessels. This study evaluated, for the first time, the performance of a self-expanding drug eluting stent in this scenario. The primary objective was to compare the in-stent late lumen loss by quantitative coronary angiography at the end of eight months between the Sparrow® drug-elutig stent and Sparrow® bare metal stent in coronary arteries with reference diameter <=2.75 mm. Materials and methods: Patients were prospectively randomized (1:1) Analysis by quantitative coronary angiography was performed immediately before and after the procedure and at eight months with clinical follow-up to 12 months. We used the IBM® SPSS for statistical analysis and was considered a significance level of 5% and 80% power for the calculation of sample size. Results: 24 patients were randomized, 12 in each group. At Eight months follow-up there was significant reduction in late lumen loss in the Sparrow® drug-eluting stent group compared to the Sparrow® bare metal stent group (0.25 ± 0.16 mm vs. 0.97 + 0.76 mm, p = 0.008, 95% CI -1.19 to -0.22). Up to 12 months of clinical follow-up there no cases of death, myocardial infarction and target vessel revascularization Of note, there was no stent thrombosis. Conclusion: In patients undergoing percutaneous transluminal angioplasty in coronary arteries with reference diameter <= 2.75 mm, the use of Sparrow® drug-eluting stent, compared to the Sparrow® bare metal stent, resulted in significant less late loss without occurrence of clinical events that weigh against the security of device.

PROPOSIÇÃO: O objetivo deste trabalho foi avaliar a força gerada pela deflexão de fios ortodônticos de Nitinol associados a diferentes tipos de braquetes por meio da avaliação dos valores da força através do aumento gradual do calibre e da deflexão dos fios e comparação entre as distintas combinações, nas diferentes deflexões. MATERIAL E MÉTODOS: Os corpos de prova foram montados em um modelo de simulação clínica e avaliados em uma máquina de ensaio universal INSTRON 3342, com célula de carga de 10N e, como protocolo, foi seguida a norma ISO 15.841. Foram confeccionados cinco destes modelos para a colagem de cada conjunto de acessórios a serem testados: metálico (Mini Diamond), policarbonato com fibra de vidro e canaleta metálica (Spirit), safira (Inspire ICE) e os autoligáveis passivo (Damon Q/Ormco) e ativo (In-Ovation R/GAC). Para os testes, o dispositivo de acrílico que representava o incisivo central direito foi movimentado no sentido palatino-vestibular, com leituras das resistências geradas nas deflexões de 3; 2; 1 e 0,5mm, com velocidade constante de 2mm/min. Os resultados foram avaliados por meio da análise de variância (ANOVA) a dois e a um critério, havendo diferença significante, a análise comparativa das médias foi feita por meio do teste de Tukey (p<0,05). RESULTADOS: A força de desativação foi gradativamente maior, com o aumento do calibre dos arcos e maior deflexão, nos diferentes tipos de braquetes. Nas combinações entre os diferentes tipos de braquetes selecionados com os fios de Nitinol verificou-se que os braquetes autoligáveis foram os que apresentaram os resultados mais parecidos entre si, mantendo-os decrescentes conforme a deflexão diminuía. Já, entre os braquetes convencionais Mini Diamond, Spirit e Inspire ICE verificou-se que não existe um padrão em nenhuma deflexão estudada. CONCLUSÕES: A avaliação dos valores da força, através do aumento gradual do calibre e da deflexão dos fios, demonstrou que a mesma foi crescente em todos os braquetes avaliados. Os braquetes autoligáveis foram os que apresentaram os resultados mais constantes e previsíveis enquanto que nos demais essa característica não foi observada. / OBJECTIVE: The purpose of this study was to evaluate the deflection forces of Nitinol orthodontic wires, placed in different kinds of brackets by assessing strength values variation according to gradual increase in the diameter and the deflection of the wires, comparing the different combinations, in the different deflections. MATERIAL AND METHODS: Specimens were mounted in a clinical simulation model and evaluated in a Universal Testing Machine (INSTRON 3342), using a 10 N load cell and, as a protocol, ISO 15841. Five of these models were prepared, each one for the bonding of each set of accessories to be tested: metallic (Mini Diamond), reinforced polycarbonate with metallic slots (Spirit), sapphire (Inspire ICE), and passive (Damon Q/Ormco) and active self-ligated (In-Ovation R/GAC). For performing the tests, the acrylic device corresponding to the right central incisor was moved in the buccal-lingual direction, and values of resistance generated for 3, 2, 1 and 0.5mm deflections, at a constant speed of 2mm/min, were registered. Data were subjected to Oneand Two-way ANOVA; since significant differences were observed, comparative analysis of mean values was performed by Tukey\'s post hoc test (p<0.05). RESULTS: Elastic deflection results showed that deactivation force increased with increase in the diameter of the wires and deflection in the different brackets evaluated. For the combinations of the different types of brackets with the Nitinol wires, it was found that self-ligating brackets were those with the most similar results to each other, which decreased as the deflection was decreased. For Mini Diamond, Spirit and Inspire ICE conventional brackets there was no pattern for any of the deflections studied. CONCLUSIONS: Strength values evaluation according to gradual increase in the diameter and the deflection of the wires showed that it increased in all evaluated brackets. Self-ligating brackets were those which presented the most consistent and predictable results while for others kinds of brackets such pattern was not observed.

Introdução: Programas de exercício físico têm sido recomendados preventivamente para promover uma maior modelação óssea. A escolha da modalidade de exercício físico, assim como a manipulação de variáveis do exercício durante os programas de treinamento físico é tema ainda controverso. Incrementos de carga e presença de impacto durante o exercício físico têm sido princípios utilizados na maioria dos programas de exercício. Objetivos: Avaliar a eficiência de dois modelos de exercícios sem sobrecarga ou impacto e impacto mínimo. Método e material: Foram utilizadas 36 ratas Wistar, randomizadas em três grupos: Grupo Roda (GR), Grupo Natação (GN e Grupo Controle (GC). Os grupos foram treinados durante 32 semanas, após as quais foram sacrificados. Resultados: Estudaram-se as propriedades mecânicas da tíbia e fêmur, a saber, momento de inércia, força máxima, flecha e tensão, assim como a densidade e conteúdo mineral do ósseo na tíbia, fêmur e coluna vertebral. Os resultados mostraram aumento da modelação óssea, principalmente na coluna vertebral e aumento do conteúdo mineral ósseo. Houve também aumento das propriedades biomecânicas das ratas treinadas comparadas com o grupo controle. O GR apresentou maior modelação óssea quando comparado co o GN. Não houve correlações entre os ensaios mecânicos e a densidade e conteúdo mineral ósseo. Conclusões: O modelo de exercícios empregado mostrou-se eficaz para promover maior modelação óssea. / Introduction: Preventive physical exercise\'s programs have been recommended in order to promote a bigger bone shape. Physical exercises modality selection, as well as exercises variable manipulation during physical training programming is a controversial topic yet. Weight increase and impact\'s presence during physical exercise have been principles used in the majority of exercise programming. Objective: to evaluate two models of exercise without overload and impact and minimal impact efficacy. Method and Materials: Thirty six female Wistar rats, at random divided in three groups, have utilized: Wheel Group (WG), Swimming Group (SG) and Control Group (CG). They trained for 32 weeks and then were sacrificed. Mechanical properties of tibia and femur such as inactivity moment, maximum strength, flexibility and tension were studied. Tibia, femur and spine density and mineral bone content were studied. Results: Results proved bone shape increase, mainly at the spine, as well as bone mineral density. Biochemical properties increased in trained when compared to Control Group female rats. No correlation was found among mechanical trails, density and mineral bone content. Conclusions: Pattern utilized exercises have shown their efficiency to promote a higher bone shape.

L’étude comparative de la cassation du jugement pénal entre les droits français et koweïtien doit s’effectuer à travers l’examen du rôle et des missions de la Cour de cassation, gardienne de la loi pénale. Elle assure le respect des droits et libertés individuels lorsqu’elle est saisie d’un pourvoi dans l’intérêt des parties. Les cours de cassation française et koweïtienne se rejoignent sur le domaine de la cassation en matière pénale (Le contrôle effectué dans le cadre du pourvoi en cassation et les conditions d’exercice de celui-ci). Il n’en va pas de même pour le mécanisme de pourvoi (l’exercice du pourvoi et la décision de la juridiction de cassation). Le droit koweïtien gagnerait en clarté et en efficacité en s’inspirant directement du droit français et en se libérant de l’influence exercée par la transposition du droit égyptien. Pour atteindre cet objectif, des propositions de réforme pour améliorer le système koweïtien de cassation sont présentées. / A study that aims to compare the cassation of judicial criminal judgment between that of the laws of France and Kuwait. Shall be done through the role and the mission of the Court of cassation, the guardian of criminal law. The Court ensures the protection of individual rights and freedoms once cassation appeal is submitted forward in the interest of the parties. French and Kuwait’s Court of cassation can meet on the domain field in relation to cassation in criminal matters (the control of cassation appeal and its exercisable conditions), yet it is not the same issue for the cassation appeal mechanism (the practice of the cassation appeal and the decision that of the Court).The laws implemented in Kuwait would gain clarity and efficiency that being from the direct inspiration from the French laws and liberating itself from the shackles of Egyptian laws. Reform and true commitment is the key to unlock this goal and is in turn necessary to improve cassation system of Kuwait.

A key element in evidence-based medicine approaches is the ability for clinicians to evaluate the scientific rigor and relevance of research evidence. In the treatment of diabetes, clinicians make increasingly difficult decisions about which drug regimens are best for their patients with limited evidence-based information. While the consensus is that metformin should be the initial drug treatment when diet and exercise are not sufficient, clinicians disagree on whether sulfonylureas should remain a suitable therapy after metformin. While this would be improved with further research investigating the comparative safety of therapeutic options, there is also need for better ways to synthesize available information to guide evidence-based decision-making in health services research. Study 1 summarizes the pre-existing evidence on the long-term safety risks associated with sulfonylurea therapy relative to other drug classes. Results from a series of meta-analyses provide some evidence that sulfonylureas are associated with elevated all-cause mortality and cardiovascular risks relative to several other medications, either as a monotherapy or in combination with metformin. Study 2 analyzes the comparative safety of second-line treatment in diabetic patients in the Veterans Health Administration to address gaps in the literature. Results suggest that second-line use of sulfonylureas is associated with increased risks compared to thiazolidinediones. Results also suggest that changes to existing metformin therapy may lead to differential hazards. Clinicians may disagree about the quality of the evidence as well as the relevancy to their own treatment population. Improvements in methods for evidence-based medicine that take this into account are needed. Study 3 applies an underutilized research method that allows for a more thoughtful synthesis of all available evidence. This framework allows clinicians to incorporate the scientific rigor and relevancy of previous study results when integrating new data into their current knowledge base. Results suggest an elevated risk in all models for sulfonylureas compared to thiazolidinediones and highlight the need to design more focused research to support clinical decision-making around medication safety. This novel application to evidence synthesis shows promise as applied to a health services research problem and has potential as a useful framework in other health services research areas. / 2017-12-09T00:00:00Z

Notre recherche engage une réflexion sur la transmission des techniques du corps (Mauss, 1950, 366) dans un contexte de mondialisation des pratiques sportives. Partant d’un questionnement empirique, nous interrogeons l’enseignement de la natation en Chine, au Sénégal et en France. Nous avons émis l’hypothèse que les représentations considérées comme un élément de l’apprentissage différent culturellement. A Canton, Dakar et Paris, l’étude comparée des contextes culturels (historiques, sportifs et traditionnels) et éducatifs (pédagogiques et didactiques) éclaire notre analyse des représentations des nageurs réalisée au moyen d’un questionnaire. Administré dans les trois villes, son analyse statistique se trouve confortée par les données qualitatives des observations et des entretiens. Nous pouvons conclure que les représentations de l’eau et de l’apprentissage de la natation différent selon les populations étudiées. De ce fait, cette recherche nous invite à considérer le fait de savoir nager dans un processus local de diffusion des techniques du corps incorporant dans sa transmission une part culturelle aux techniques mondialisées / Our study considers body technical transmission (Mauss, 1950, 366) in a context of sport practices globalization. After an initial empirical study of the swimming teaching in China, Senegal and France, we postulated the existence of cultural differences in representations playing a significant role in the training process. In Canton, Dakar and Paris, we established a comparative study of contexts both cultural (historical, sportive and traditional) and educative (pedagogical and didactic). We used a questionnaire as a base to apprehend swimmers representations in the three cities. Its statistical analysis was backed by qualitative data gathered from observations and interviews. We conclude that representations of water and swimming training differ among the studied populations. Therefore, this study calls for considering swimming in a local process of body technical transmission, blending a culture-specific part with globalized techniques

« Tout a ou bien un prix ou bien une dignité. On peut remplacer ce qui a un prix par un équivalent. En revanche, ce qui n’a pas de prix et donc pas d’équivalent, c’est ce qui possède une dignité». L’utilisation de la norme juridique comme fondement du principe de gratuité du don de sang ne répond pas à la question de savoir quel est le statut juridique du sang. Notre analyse rétrospective sur les prémices de la rémunération du don de sang permet de constater les carences juridiques relatives aux rapports dialectiques entre les personnes impliquées au don de sang. Notre réflexion consiste à démontrer en quoi le principe de gratuité du don de sang recommandé par le Conseil de l’Europe se légitime eu égard à l’objectif d’autosuffisance. Notre étude franco-allemande appréhende le principe de gratuité soumis aux enjeux antagonistes que soulève le don de sang. L’exigence de cette analyse juridique implique de tenir compte des facteurs pluridimensionnels d’ordre culturel, social, scientifique, économique. Le principe de gratuité révèle l’expression d’un choix « politico-juridique » et d’un juste arbitrage dans la hiérarchisation des valeurs et des priorités, plutôt que l’existence d’un statut juridique propre au produit sanguin.Nietzsche exposait déjà l’indissoluble dilemme car « dans l’éloge de la vertu on n’a jamais été bien désintéressé, on n’a jamais été bien altruiste». Nous démontrons l’intérêt de penser une certaine « médiété » entre les considérations éthiques très prononcées en France et les considérations industrielles et commerciales, capitales en Allemagne. De nouveaux aménagements juridiques ont ainsi été suggérés dans le cadre d’une alliance. / «Everything has either a price or a dignity.We can replace what has a price by an equivalent.On the other hand, the one which has no price, and therefore no equivalent, is the one which has a dignity.»Using the legal standard as the basis of the principle of free blood donation does not answer the question of what is the legal status of blood.However after a retrospective analysis of the beginnings of the remuneration of blood donation, the legal deficiencies on dialectical relationship between the people involved in the therapeutic use of blood donation are highlighted.Thus our discussion is to demonstrate how the principle of free blood donation recommended by the Council of Europe member states is legitimate in view of the goal of self-sufficiency.Our franco-german comparative study captures the principle of gratuity subject to conflicting issues raised by blood donation.To identify the requirements of the legal analysis, the multidimensional economic, cultural, social, scientific factors must consubstantially be taken into account.The principle of gratuity reveals the expression of a «political and legal» choice and arbitration in the hierarchy of values and priorities, rather than the existence of a legal status specific to blood product.Nietzsche had already outlined the indissoluble dilemma as «in the praise of virtue, people have never been very disinterested, they have never been good altruists.»We demonstrate the benefit of thinking a kind of «mediatedness» between the highly pronounced ethical considerations in France, and the industrial and commercial considerations, capital in Germany.New legal arrangements have been suggested within a franco-german alliance.

Foi feito um estudo comparativo da ação inibidora dos compostos benzotriazol (BTAH) e tolitriazol (TTAH) sobre a oxidação de metais ferrosos e sobre a reação H+/H2, sobre ferro, em meios de ácido sulfúrico. Foram estudados, como metais ferrosos, o ferro puro (99,9% de pureza), em meio de H2SO4 0,5molL-1, o aço carbono 1008, em H2SO4 0,5mol L-1e o aço inoxidável 304, em meio de H2SO4 4,5 mol L-1. Foram empregadas, como técnicas, medidas de potencial de circuito aberto em função do tempo, ensaios gravimétricos, curvas de polarização potenciostáticas, voltametria linear com eletrodo parado e com eletrodo de disco rotativo, cronoamperometria, espectroscopia por impedância eletroquímica, espectroscopia Raman e microscopia eletrônica de varredura (MEV). Os compostos BTAH e TTAH atuaram como inibidores para os três materiais ferrosos estudados. No caso do aço carbono 1008 e do aço inoxidável 304, os efeitos dos dois inibidores se comparam e, para uma concentração igual a 1,0 x 10-2 mol L-1 apresentam uma eficiência máxima de 98%, verificada por técnicas estacionárias e não estacionárias. O TTAH, em mais baixa concentração, se mostrou melhor inibidor para o aço carbono, enquanto para o aço inoxidável 304 foi tão bom inibidor quanto o BTAH. Análise das superfícies por MEV mostrou que os inibidores não impedem a dissolução das inclusões presentes nos aços estudados, permitindo o ataque localizado no entorno das mesmas, no caso do aço 304. Os compostos BTAH e TTAH se mostraram inibidores menos efetivos para o ferro, com eficiências comparáveis e iguais a 60% na concentração mais elevada estudada, 1,0 x 10-2 mol L-1 . O estudo da oxidação do ferro, na região de Tafel, empregando impedância eletroquímica, mostrou que o BTAH e o TTAH atuam de forma comparável, formando um complexo com o intermediário Fe (II) adsorvido. Ensaios por espectroscopia Raman in situ revelaram que há formação de complexos de ferro com o BTAH e TTAH. Os resultados de impedância eletroquímica, juntamente com os de espectroscopia Raman do complexo Fe(II)BTA sólido levaram à conclusão de que o filme inibidor sobre ferro é o próprio complexo Fe(II)BTA. Estudos de polarização catódica sobre ferro, em meio desaerado, mostraram que tanto o BTAH quanto o TTAH inibem a reação H+/H2, através da formação de um filme que obedece à isoterma de adsorção de Langmuir. Valores de &#916;Gº de adsorção sugerem que a adsorção é de natureza química, o que foi confirmado por espectroscopia Raman. Estudos empregando voltametria de baixa velocidade de varredura, com eletrodo de disco rotativo, mostraram que a ação inibidora é favorecida pelo maior transporte de massa à superfície do eletrodo de ferro. Os resultados de impedância permitiram sugerir dois diferentes mecanismos para a ação dos inibidores sobre o processo de oxidação do ferro em meio de ácido sulfúrico. / A comparative study of the inhibitor behavior of benzotriazol (BTAH) and tolitriazol (TTAH) over the oxidation of ferrous metals and over the reaction H+/H2, over iron in sulfuric acid media has been performed. The ferrous metals studied were pure Iron (99.9% purity) and carbon steel 1008, both in 0.5 mol.L-1 H2SO4 and 304 stainless steel in 4.5 mol.L-1 H2SO4. The techniques employed were, open circuit potential vs. time, gravimetry, potentiostatic polarization curves, linear voltammetry with both stationary and rotating disk electrodes, chronoamperometry, electrochemical impedance spectroscopy, Raman spectroscopy and scanning electron microscopy (SEM). BTAH and TTAH have shown to act as inhibitors for the three studied ferrous metals. The inhibiting effect of these compounds was analogous for both carbon steel 1008 and 304 stainless steel. Furthermore stationary and non-stationary techniques have shown that both inhibitors exhibited the maximum of efficiency (98%) in 1.0 x 10-2 mol.L-1. For the lowest studied concentration, TTAH exhibited a better inhibiting effect over the carbon steel, while for the 304 stainless steel TTAH and BTAH presented the same inhibiting efficiency. SEM Analysis of the surfaces showed that the inhibitors do not avoid the dissolution of the inclusions that exist in the studied steels, instead, for 304 stainless steel they permit a localized attack on the contour of the inclusions. Both BTAH and TTAH have shown a less effective inhibitory effect for iron with 60% of efficiency for the highest studied concentration (1.0 x 10-2 mol.L-1). The study of the oxidation of iron performed on the Tafel region by electrochemical impedance spectroscopy showed that both BTAH and TTAH act similarly, forming a complex with the adsorbed intermediary Fe(II). Raman spectroscopy measurements performed in situ indicated the formation of iron complexes with BTAH and TTAH. The analysis of the results obtained for the complex Fe(II)BTA with both electrochemical impedance spectroscopy and Raman spectroscopy techniques revealed that this complex forms the inhibitor film. Cathodic polarization studies performed for iron in dearated media showed that both BTAH and TTAH forma film that obeys to the Langmuir adsorption isotherm on the iron surface which inhibits the H+/H2 reaction. Furthermore &#916;Gº adsorption values suggest that the adsorption is chemical in nature which was confirmed by Raman spectroscopy. Low rate voltammetry studies performed with rotating disk electrode, showed that the inhibitory effect is favored by the mass transport towards the iron electrode surface. From the impedance spectroscopy results two different mechanisms could be proposed to the inhibitor effect over the process of iron oxidation in sulfuric acid media.

Previous membrane researches undertaken over the years to develop general deadend filtration models made use of an approach that combined all three classical fouling mechanisms, namely, pore blocking, pore constriction and cake filtration. More recently researchers have modified and adapted this modelling approach for a cross flow side-stream membrane bioreactor (MBR) system. Literature also reveals that there have been numerous recent experimental studies conducted on rotating membrane bioreactor (RMBR) systems. Some of these studies have resulted in the creation of RMBR models of the membrane fouling process as well. However, simulation and modelling of the fouling in RMBRs is still a nascent topic to date due to poor understanding and great complexity of the system hydrodynamics involved. Even when models are developed, they are either too complex to be useful at operational level, or not comprehensive enough to express all possible operational scenarios. In many cases they are simply too difficult to calibrate and thus ending up being more suited as research tools rather than for direct process control. As such, further research is required in this area. The research reported in this thesis consists of the development and validation of a RMBR system fouling model that incorporates all three classical fouling mechanisms. This thesis work is divided into two main sections. On top of a literature review that thoroughly describes the background theory and general information on MBRs along with their state of the art, the first section of the thesis also explains the specific methodologies used to accomplish all the main tasks carried out in this research work. The first step of these methodologies involves the setting-up of a rotating MBR system process based upon the FUV-185-A15R Flexidisks membrane module that was developed by Avanti Membrane Technology (USA). This system was used to collect the majority of the data used in this thesis. Since some of these data outputs were compared against non-rotating MBR systems, a similar setting-up process for a bespoke static square MBR system was carried out as well. Using synthetic wastewater in conjunction with activated sludge, mixed liquor suspended solids in both MBR system bioreactors were increased in levels over time to desired levels (i.e. by periodic excess sludge wasting). Trans-membrane pressure (TMP)-stepping fouling data was then acquired from operations of these membrane ultrafiltration processes. This data was obtained by measuring the flux decline or TMP increase. Following data collection, a dynamic fouling model for this RMBR system was then created in Matlab (using the Genetic Algorithm function). To do this, hydrodynamic regimes such as air scouring and rotating shear effects along with all the three classical fouling mechanisms were included in the mathematical fouling model that was created from first principles. For the purpose of comparison, a similar fouling model was created without incorporating the rotational effects for the static square MBR system. This included modelling of the hydrodynamics as well. Finally, both these models were validated and calibrated using the data that were collected from both laboratory-based MBR systems. The second phase of the thesis explores the numerous outputted results produced via model simulations which were then discussed and analysed in great detail. Results from this research indicate that the mathematical models give a decent portrayal and description of the fouling mechanisms occurring within a rotating MBR system. It was found that the rotational mechanisms in terms of fouling prevention accounted for only twelve percent of cake removal with the rest being accomplished through the air scouring mechanism. However, it was found that although the slowly rotating spindle induced a weak crossflow shear, it was still able to even out cake build up across the membrane surface, thus reducing the likelihood of localised critical flux being exceeded, which would lead to dramatic loss of flux. Furthermore, when compared against the static MBR system, the study concluded that a rotating MBR system could increase the flux throughput by a significant amount. In conclusion, RMBR systems appear to represent alternative viable solutions when compared against the traditional static MBR systems that currently dominate the industrial and municipal marketplace. In future, RMBR systems may become the systems of first choice once there is a better understanding of the rotational processes, and once research and design into this sector broadens. Future study areas should thus focus on: whether the forces acting on an activated sludge particle during rotation have a significant effect on the fouling or the shear hydrodynamic regimes; whether activated sludge and benchmark models could be created for rotating MBRs whilst including the shear effects and hydrodynamic regimes; whether model predictive control using these developed RMBR models would enhance efficiency gains within an operational plant; and, whether the real measured soluble microbial products (SMP) concentrations could be used to create an even better SMP predictive model that accurately explains fouling behaviour.