Bakgrund: För att prestera på elitnivå behöver Fotbollsspelare en välutvecklad aerob och anaerob effekt och kapacitet. Repeated sprint ability (RSA) är en anaerob förmåga som kan avgöra många matchsituationer, till exempel bollinnehav och målchanser. För att testa RSA görs ett repeated sprint ability test (RST). Syreupptagningsförmågan testas ofta genom olika konditionstester. Syftet med denna studie var att undersöka korrelationen mellan RST, Yo-Yo Intermittent Recovery Level 1 test (Yo-Yo IR1) och 30-15 Intermittent Fitness Test (30-15IFT). Metod: Nio damfotbollsspelare som randomiserades in i två grupper (Grupp 1, n=5, 22±3 år, kroppsvikt 64±12,8 kg och grupp 2, n=4, 20±3 år, kroppsvikt 64,2±2,4 kg). Deltagarna genomförde antingen RST och/eller Yo-Yo IR1 vid ett tillfälle och vid nästa tillfälle RST och/eller 30-15IFT. Alla tester skedde utomhus på en konstgräsplan. På Yo-Yo IR1 och 30-15IFT dokumenterades sluthastigheten. På RST dokumenterades den totala sprinttiden (RSTtotal) och %trötthet mellan bästa sprinten jämfört med resterande sprinter (RST%dec). Resultatet på testerna presenteras som en grupp i medelvärde och standardavvikelse (SD). Uträkningen av korrelationen användes Pearsons Korrelationskoefficient (r). Statistisk nivå för signifikans var p <0.05. Resultat: Korrelationen mellan Yo-Yo IR1 mot 30-15IFT samt 30-15IFT mot RSTtotal hade en väldigt stark statistiskt signifikant korrelation (r = 0.855; respektive r= -0.721). Det fanns inte någon statistiskt signifikant korrelation mellan Yo-Yo IR1 mot RSTtotal, IRL mot RST%dec, och 30-15IFT mot RST%dec (r= -0.704; r=0.209 respektive r=-0.02). Konklusion: Resultaten indikerar att det finns en väldigt stark korrelation mellan Yo-Yo IR1 och 30-15IFT och fördelar mot nackdelar bör vägas för att använda vilket test. 30-15IFT verkar använda en högre andel RSA eftersom det hade en starkare korrelation till RST än Yo-Yo IR1.

No description available.

La dégénérescence maculaire liée à l’âge (DMLA) est une des premières causes de cécité pour les personnes âgées de plus de 50 ans. Elle existe sous deux formes : sèche et humide. La forme causant les pertes de vision les plus sévères et rapides est DMLA humide où des nouveaux vaisseaux sanguins anormaux se forment dans la rétine; ce processus est appelé la néovascularisation choroïdienne. Celui-ci est causé par la dégradation des différentes membranes de la rétine et de l’augmentation du VEGF stimulant la croissance de ces vaisseaux. L’obésité, l’hypertension, le diabète et la cigarette sont connus pour être des facteurs modifiables et fortement corrélés avec la maladie. Avec l’arrivée des nombreuses diètes tendances, le jeûne intermittent pourrait être une intervention non-pharmacologique impactant l’obésité, l’hypertension et le diabète. En effet, cette diète est reconnue pour améliorer la santé, améliore la sensibilité à l’insuline et la tolérance glucose, diminuer le cholestérol sanguin et exercerait un effet bénéfique sur l’obésité. Ce mémoire a été entrepris dans le but d’évaluer les avantages potentiels du cycle de diète, soit le jeûne intermittent, sur la néovascularisation choroïdienne dans un modèle de DMLA. Nous avons émis l’hypothèse que le jeûne intermittent permet la diminution de la néovascularisation choroïdienne. Nos résultats montrent que les souris sous le régime jeûne intermittent que nous avons utilisé, c’est-à-dire 2 jours d’alimentation pour 1 jour de jeûne, ne perdent pas de poids, et suivent le même schéma de prise de poids que les souris nourries à volonté. De plus, les souris sous jeûne intermittent n’ont pas d’avantage métabolique que ce soit au niveau du glucose et, encore, moins au niveau de l’insuline. Les résultats ne permettent pas de montrer une différence au niveau de la néovascularisation choroïdienne induit par notre modèle. Le modèle de jeûne intermittent choisit ne permet pas d’obtenir des avantages au niveau de la néovascularisation choroïdienne ni pour la sensibilité au glucose et à l’insuline / Age-related macular degeneration (AMD) is one of the most prominent causes of blindness for people over 50 years old. It exists in two forms: dry and wet. The form causing majority of loss of sight is caused by wet AMD from where new abnormal blood vessels form in retina. This process is called choroidal neovascularization. This is caused by degeneration of outer portion of the retina and an increase in VEGF that instigate the growth of the new blood vessels. Obesity, hypertension, diabetes and smoking are known to be modifiable factors and strongly correlated with the disease. The advent of a vast number of trendy diets has introduced the possibility of modulating chronic disease by modifying eating habits. As an example, intermittent fasting can impacting obesity, hypertension, and diabetes. Indeed, this diet has been known to improve health, increase sensitivity of insulin and glucose, lower cholesterol and to have beneficial effect in obesity. The purpose of the research in my master’s thesis is to evaluate the influence of diet cycle, intermittent fasting on choroidal neovascularization in a mouse model of AMD. We hypothesized that the intermittent fasting could be diminish the choroidal neovascularization. There are several experimental paradigms that reproduce intermittent fasting. We selected the intermittent fasting 2 days of eating for one day of fasting (IF 2:1). Our results show that mice on our selected intermittent fasting regimen did not lose weight and follow the same pattern of weight gain as the mice that fed ad libitum. Furthermore, the mice on this intermittent fasting diet paradigm didn’t have metabolic benefits on glucose or insulin tolerance. Our results also did not show any differences in choroidal neovascularization. Hence, the 2:1 paradigm of intermittent fasting didn’t show any benefits on choroidal neovascularization, nor glucose and insulin.

Bakgrund: Allt fler individer i välutvecklade länder kan klassificeras som överviktiga. Övervikt och fetma ökar risken för en mängd olika sjukdomar och är en av de främsta orsakerna till sjukdomsbördan och för tidig död i Sverige. Det finns därför behov för att kunna rekommendera effektiva kostinterventioner. Kontinuerlig energirestriktion är den vanligaste kostinterventionen, men det finns behov för att kunna rekommendera alternativa kostinterventioner.Syfte: Syftet med denna litteraturstudie var att sammanställa resultaten från randomiserade kontrollerade studier från de senaste fem åren som undersöker effekten av intermittent fasta och tidsbegränsat energiintag jämfört med kontinuerlig energirestriktion på viktreduktion och kroppskomposition.Metod: Litteratursökningen gjordes i databaserna Web of Science och PubMed. Sökningen resulterade i 612 träffar varav tio inkluderades i studien.Resultat: Tre av tio studier påvisade skillnader mellan kostinterventionerna gällande viktreduktion; en till fördel för intermittent fasta jämfört med kontinuerlig energirestriktion (p<0,01) en till fördel för tidsbegränsat energiintag jämfört med kontinuerlig energirestriktion (p<0,05) och en till fördel för kontinuerlig energirestriktion jämfört med intermittent fasta (p<0,05). Två av tio studier påvisade skillnad mellan kostinterventionerna i mängden tappad fettmassa till fördel för intermittent fasta (p<0,01) och tidsbegränsat energiintag (p<0,05) jämfört med kontinuerlig energirestriktion.Konklusion: Intermittent fasta och tidsbegränsat energiintag har i denna litteraturöversikt visat på likvärdiga resultat på viktreduktion och kroppskomposition jämfört med kontinuerlig energirestriktion. Resultaten i de granskade studierna tyder på att det är följsamheten av kostinterventionen som är avgörande för viktreduktion och inte själva kostinterventionen i sig. / Background: There is an increase in overweight and obese people around the world. Overweight and obesity increases the risk of multiple diseases and comorbidities. Continuous energy restriction is the most used diet method. However, research suggests that adherence to the diet diminishes within a couple of months, therefore research in alternative methods has increased. Objectives: The objectives of this literature review were to review the latest literature since 2017 regarding the effects of intermittent fasting and time-restricted feeding compared to continuous energy restriction on weight loss and body composition.Methods: The literature search was done in Web of Science and PubMed. The search resulted in 612 articles. Ten of the 612 articles were included in the literature review.Results: Three out of ten studies showed significant differences between groups regarding weight loss. One in favor of intermittent fasting compared to continuous energy restriction (p<0,01), one in favor of time-restricted feeding compared to continuous energy restriction (p<0,05) and one in favor of continuous energy restriction compared to intermittent fasting (p=0,03). Two out of ten studies showed a significant difference between groups regarding reduction of fat mass in favor of intermittent fasting (p<0,01) and time-restricted feeding (p<0,05) compared to continuous energy restriction.Conclusion: This literature review suggests that intermittent fasting and time-restricted feeding when compared to continuous energy restriction has similar effects on weight loss and body composition. The results of the studies suggest that it is the adherence of the diet that is vital for successful weight loss and not the diet itself.

The following thesis investigates contemporary issues within the applied physiology of soccer refereeing. 1) Training performance. The impact of a high intensity training regime was examined in a group of elite-level soccer referees. Following a 16-month training period the referees’ performance on the YoYo Intermittent Recovery Test (level 1) improved by 46.5%. 2) Match Demands. The effect of match standard and referee experience upon the objective and subjective match loads of referees was investigated. Match heart rates (HR) and ratings of perceived exertion (RPE) were both related to standard of competition, with the match loads being higher on the higher standard of competition. Referee experience had no effect upon the referees’ match responses. Using a semi-automatic, video match analysis system the referees’ match activities and factors affecting these activities were also examined. Physical performances were related in part to the physical performances of the players; whilst the distances covered during the first half were related to second half coverage. 3) Ageing and performance. The effect of ageing upon referees’ fitness levels and physical match performances was addressed. Regression analysis revealed a trend towards an agerelated reduction in physical fitness, as determined by the referees’ fitness tests. Match activity analysis demonstrated a clear age-related decline in physical match performance, although this decline did not impair the referees’ ability to keep up with play. 4) Fitness and match performance. The validity of the FIFA referees’ fitness tests was examined. Interval test HR load was significantly correlated to the referees’ match coverage, both total distance and high intensity running. Sprint test scores also demonstrated a significant relationship with the referees’ match sprinting distances. However, given the strength of the relationships only the sprint test showed appropriate construct validity for the physical assessment of soccer referees.

Thesis (MScPhysio)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Question: What are the effects of Intermittent Positive Pressure Breathing (with and without a Positive End Expiratory Pressure [PEEP] Valve), compared to deep breathing exercises, on ventilation distribution in high-risk adults following open upper abdominal surgery (UAS)? Design: This study comprised an observational descriptive component as well as a prospective triple blind randomised controlled crossover trial with concealed allocation and patient, assessor and statistician blinding Participants: Seven patients at high risk for postoperative pulmonary complications following UAS Intervention: Deep breathing exercises (DBExs) were compared to Intermittent Positive Pressure Breathing (IPPB), with IPPB further applied with and without a PEEP Valve, using a randomised cross-over design with 30 minute washout duration between periods. Outcome measures: Global and regional impedance changes in the lungs were measured using Electrical Impedance Tomography. Vital signs, visual analogue pain scale (VAS) and modified Borg scale (MBS) were measured pre– and post-intervention. Results: A greater mean global lung impedance change ( Z) was detected with IPPB compared to DBExs (mean difference in Z 2803.8; 95% CI 5189.9 to 8512.5 and 2046 to 96047.9; P<0.01). These changes in lung impedance lasted 30 minutes before returning to baseline. There was no difference in Z when patients received IPPB with 5cmH20 PEEP compared to IPPB with no PEEP. No specific regional ventilation changes were noted. IPPB did not increase VAS, MBS scores or adversely affect vital signs. Conclusion: IPPB is an effective technique to improve lung volumes compared to deep breathing exercises. Further studies are required to investigate the effect of IPPB on clinical outcome. / AFRIKAANSE OPSOMMING: Vraag: Watter uitwerking het onderbroke positiewe-drukasemhaling (met én sonder ’n positiewe-endekspiratoriesedruk-[PEEP-]klep) in vergelyking met diepasemhalings-oefeninge op ventilasieverspreiding by hoërisikovolwassenes ná bo-buikchirurgie? Ontwerp: ’n Waarnemingsgegronde, vergelykende en ondersoekende, driedubbelblinde, verewekansigde gekontroleerde oorskakelproef, met verborge toewysing en blinding van pasiënte, die assesseerder en statistikus Deelnemers: Sewe pasiënte met ’n hoë risiko vir post-operatiewe pulmonêre komplikasies na bo-buikchirurgie Intervensie: Diepasemhalingsoefeninge (DBEx) is vergelyk met onderbroke positiewedrukasemhaling (IPPB), wat op sy beurt met én sonder ’n PEEP-klep toegepas is, met behulp van ’n verewekansigde oorskakelstudie met ’n halfuur lange uitspoeling tussen oorskakelings. Uitkomsmetings: Algehele en regionale impedansieveranderinge in die longe is met behulp van elektriese impedansietomografie gemeet. Vitale tekens, die visuele analoogskaal (VAS) en die aangepaste Borg-skaal (MBS) is voor, sowel as na die intervensie afgeneem. Resultate: ’n Groter gemiddelde algehele impedansieverandering ( Z) is opgemerk met IPPB in vergelyking met DBEx (gemiddelde verskil 2803.8; 95% CI 5189.9: 8512.5 en 2046: 96047.9; P<0.01). Hierdie veranderinge in longimpedansie het ’n halfuur of langer geduur voordat dit na die basislyn teruggekeer het. Daar was geen verskil in Z toe pasiënte IPPB met ’n PEEP-klep van 5cmH20 ontvang het teenoor IPPB sonder ’n PEEP-klep nie. Geen spesifieke regionale voorkeure is opgemerk nie. IPPB het nie die VAS- of MBS-tellings verhoog of vitale tekens verswak nie. Stellenbosch University https://scholar.sun.ac.za iv Gevolgtrekking: In vergelyking met DBEx, is IPPB ’n doeltreffende tegniek om longvolumes te verbeter. Verdere studies word vereis om die uitwerking van IPPB op kliniese uitkomste te ondersoek.

No description available.

Inicialmente caracterizada como proteína supressora de tumor, a PTEN (phosphatase and tensin deleted on chromosome 10) tem sido objeto de estudo de trabalhos relacionados a outros processos envolvendo proliferação, sobrevivência e migração celulares, apresentando um potencial papel modulatório na neurogênese e plasticidade sináptica. Fatores ambientais, como a dieta intermitente e o exercício físico, também podem modular estes processos, podendo ser utilizados como intervenções para neuroproteção e melhora de déficits de aprendizado e memória. A ausência de PTEN em neurônios ocasiona anomalias anatômicas e funcionais, culminando em sinaptogênese aumentada e redução do LTP e LTD. Levando-se em consideração a potencial modulação da via PI3K/AKT pela dieta intermitente e pelo exercício físico, a avaliação da influência destas intervenções sobre os efeitos da deleção neuronal da PTEN constitui uma interessante ferramenta de estudo para melhor elucidação dos mecanismos associados à plasticidade sináptica. Este trabalho objetivou caracterizar bioquímica e funcionalmente o hipocampo e o córtex de camundongos adultos com deleção neuronal da PTEN, avaliando seus efeitos sob influência de intervenções não-farmacológicas. Para isto, foram utilizados camundongos com nocaute neuronal condicionado da PTEN (PtenloxP/+;Nse-Cre+). Os animais foram submetidos à dieta intermitente ou exercício físico voluntário por um período de 30 dias, avaliados por ensaios comportamentais (labirinto em cruz elevado, campo aberto, reconhecimento do objeto novo ou da localização do objeto, labirinto aquático de Morris e esquiva inibitória) e, posteriormente, foram realizadas as análises de Western Blotting, da atividade da enzima óxido nítrico sintase (NOS) e dosagem do fator neurotrófico derivado do encéfalo (BDNF). A deleção neuronal da PTEN induziu macrocefalia por aumento da massa cortical. A deleção condicionada da PTEN, sob estímulo de intervenção não-farmacológica dieta intermitente ou exercício físico induz um efeito ansiolítico nos animais, no labirinto em cruz elevado. Os resultados do campo aberto, porém, paradoxalmente não reforçam este resultado. Interessantemente, o isolamento social intrínseco ao estudo do exercício físico induziu um aumento do perfil de ansiedade nos animais, independentemente do genótipo ou tratamento. Os resultados do labirinto aquático de Morris não foram conclusivos, porém apontam para um possível déficit de memória espacial nos animais HT, além de, supreendentemente, um efeito deletério do exercício físico também observado nos níveis corticais de BDNF. Na esquiva inibitória, o déficit dos animais HT foi efetivamente resgatado pela dieta e pelo exercício físico. O hipocampo não apresentou alterações bioquímicas significativas. No córtex, pode-se confirmar a diminuição da expressão da PTEN e possível ativação da AKT, embora nenhum efeito sobre os receptores ionotrópicos glutamatérgicos tenha sido observado. O perfil de expressão da Cre recombinase foi validado por meio da linhagem Nse-Cre+;tdTomato+. O estudo da linhagem PtenloxP/+;Nse-Cre+ demonstrou um interessante potencial para avaliação dos efeitos da PTEN sobre a cognição e a plasticidade sináptica, porém um melhor balizamento dos ensaios faz-se necessário, visando a busca de condições de análise dos efeitos observados. Ainda, a expansão dos estudos com a linhagem por meio da utilização de outros estímulos pode constituir uma interessante forma de revelar os efeitos não observados. / First characterized as a tumor suppressor, PTEN (phosphatase and tensin deleted on chromosome 10) has been a target studied in many projects related to processes involving cell proliferation, survival and migration, showing a potential modulatory role in controlling neurogenesis and synaptic plasticity. Environmental factors, such as intermittent fasting and physical exercise, can also modulate those processes, thus having the potential of being applied as neuroprotective interventions aiming to improve learning and memory deficits. PTEN absence in neurons cause anatomical and functional anomalies, culminating in increased synaptogenesis and LTP and LTD reduction. Considering the potential of intermittent fasting and physical exercise to exert a modulatory role over the PI3K/AKT pathway, the assessment of the influence of these interventions over the effects of PTEN neuronal deletion is of great interest, as it can help better elucidate the mechanisms of synaptic plasticity. This work aimed to functionally and biochemically assess the hippocampus and the cortex of adult mice with a conditioned neuronal deletion of PTEN (PtenloxP/+;Nse-Cre+), evaluating its effects under the influence of non-pharmacological interventions. Animals were submitted to an intermittent fasting or to a voluntary physical exercise protocol for 30 days, then assessed by behavioral (elevated plus maze, open field, novel object or object location recognition tests, Morris water maze, and passive avoidance) and biochemical (Western blotting, nitric oxide synthase activity, BDNF levels) assays. The neuronal PTEN deletion induced macrocephaly through an increase in cortical mass. Also, under the stimuli of non-pharmacological interventions intermittent fasting or physical exercise the deletion induced an anxiolytic effect on the elevated plus maze assay. On the other hand, the open field results were paradoxical. Interestingly, social isolation an intrinsic factor from the physical exercise protocol induced an increase in the anxiety behavior, independently of genotype or treatment. Results from the Morris water maze assay were not conclusive, however they pointed to a likely spatial memory deficit on animals with the PTEN deletion. Surprisingly, a deleterious effect of physical exercise was also observed an effect found on BDNF levels as well. At the passive avoidance test, the deficit from the HT group was effectively rescued by either intermittent fasting and physical exercise. The hippocampus did not show any significant biochemical alterations. However, the decreased PTEN expression was confirmed in the cortex, as well as the possible AKT activation, although any effect over the glutamatergic ionotropic receptor was found. The Cre recombinase expression profile was validated through the reporter lineage Nse-Cre+;tdTomato+. The study of PtenloxP/+;Nse-Cre+ lineage showed great potential of assessing PTEN effects on cognition and synaptic plasticity. However, a deeper standardization of parameters is recommended in order to better evaluate the observed effects. In addition, by expanding the study of this lineage through the application of other stimuli could constitute an interesting way of revealing these non-observed results.

Um Reator com Aeração Intermitente e Leito Estruturado (RAILE) foi testado como pós- tratamento de UASB tratando efluente doméstico. O RAILE foi submetido a ciclos de uma hora de aeração e duas de anoxia, visando obtenção de Nitrificação e Desnitrificação Simultâneas (NDS) para remoção de nitrogênio. A recirculação aplicada foi de 3 vezes a vazão de entrada, para equalização da qualidade do efluente. O reator tem formato cilíndrico e seu meio suporte é espuma de poliuretano na forma de cilindros dispostos verticalmente, suportados por hastes de cloreto de polivinila (PVC) presas nas extremidades. O estudo foi dividido em duas fases em que o RAILE recebeu efluentes de UASB com diferentes relações de DQO/N-Total. Na primeira fase a relação foi 2,44 e na segunda fase a relação foi 4,01. As remoções de N-Total foram 23,7% e 65,3%, respectivamente para primeira e segunda fase. As remoçôes de DQO para todo o sistema foram 94,8%, para a primeira fase, e 93,4%, para a segunda fase. A alcalinidade se mostrou um parâmetro efetivo pra monitorar a ocorrência de NDS. Embora tenha se mostrado viável como pós-tratamento de UASB em sistemas tratando efluente doméstico, a relação DQO/N-Total precisa ser controlada para garantir o processo de NDS / A Structured Bed Intermittently Aerated reactor (SBIA) was tested as post-treatment for UASB treating domestic wastewater. The SBIA underwent cycles of one hour of aeration and two hour of anoxia to obtain Simultaneous Nitrification and Denitrification (SND) for the removal of nitrogen. The recirculation flow applied was 3 times the input flow to equalize the effluent quality. The reactor had a cylindrical shape and its support medium is polyurethane foam in the form of cylinders arranged vertically, supported by polyvinyl chloride (PVC) rods attached at the ends. The study was divided into two stages in which the SBIA received the UASB reactor effluent with different COD/Total-N ratios. The first COD/Total-N ratio was 2,44 and the second was 4,01. The removal of N-total were 23.7% and 65.3% respectively for the first and second stages. The removal of COD, in all the system, was 94.8% for the first stage and 93.4% for the second stage. The alkalinity proved to be an effective parameter to monitor the occurrence of SND. Although the SBIA proved to be feasible as post-treatment of UASB systems treating domestic wastewater the ratio COD/N-total must be controlled to ensure the process of SND

O reator em batelada seqüencial com biomassa em suspensão foi submetido a concentrações de N-amoniacal de 125, 250 e 500 mg N/L e em condições de oxigênio dissolvido (OD) no reator de 2 mg 'O IND.2'/L, em ciclos de 2h/2h de anóxico/aeróbio. Em todas as fases, o reator foi operado como batelada alimentada. Na condição de 125 mg N/L obteve-se eficiência de remoção de 87% de N, tendo o nitrato sido o principal produto da nitrificação. Na condição de 250 mg N/L, obteve-se eficiência de remoção de N de 84%, com predominância de nitrito como principal produto da nitrificação e com ocorrência de nitrificação e desnitrificação simultânea durante os dois primeiros ciclos aeróbios. Na condição de 500 mg N/L, as condições de concentração de OD de 2 mg 'O IND.2'/L e aeração intermitente a cada 2h não foram suficientes para promover a remoção total de nitrogênio amoniacal. Foram feitas alterações: ciclos de 2h anóxico e 9h aeróbios, com concentração média de 2,8 mg 'O IND.2'/L, que resultaram em eficiências de remoção de N de 94%, com predominância de nitrito. Foram isoladas cepas desnitrificantes com similaridade de 97% para Thauera mechernichensis e Thauera sp. 27 nas condições operacionais de 125 e 250 mg N/L e de 99% para Ochrobactrum anthropi e Ochrobactrum tritici, na condição operacional de 500 mg N/L. O longo tempo de operação resultou na diminuição da população de bactérias oxidantes de nitrito, podendo ter sido uma das causas que contribuiu para que se criassem condições que levariam à nitrificação via nitrito na concentração de 500 mg N/L. O sucesso na prevenção da inibição do processo por amônia livre foi atribuído à adoção das condições operacionais do reator, que foi operado sob aeração intermitente e batelada alimentada. / The sequential batch reactor with suspended bioma was subjected to ammonium concentrations of 125, 250 and 500 mg N/L, oxygen dissolved (OD) concentrations of 2 mg 'O IND.2'/L, 2h/2h of anoxic/aerobic steps. The reactor was operated under fed-batch feeding. At the operational condition of 125 mg N/L, the mean nitrogen removal efficiency of 87% was obtained and nitrate was the main nitrification product. At operational condition of 250 mg N/L, was gotten nitrogen removal efficiencies of 84% and nitrite was the predominant form of nitrogen and simultaneous nitrification and denitrification occurred during the two first aerobic steps of the cycle. At 500 mg N/L, the operating conditions imposed to the reactor (OD concentrations of 2 mg 'O IND.2'/L and intermittent aeration of 2h) did not lead to complete nitrification during the aerated steps, thus affecting nitrogen removal. The conditions were altered increasing the aerated steps to 9 hours, with OD concentration of 2,8 mg 'O IND.2'/L, and keeping the duration of the anoxic steps in 2 hours. Under such conditions, the mean nitrogen removal efficiency attained 94% and nitrite was the predominant oxidized nitrogen specie. It was isolated denitrifiers with similarity of 97% for Thauera mechernichensis and Thauera sp. 27 at the operational conditions of 125 and 250 mg N/L and of 99% for Ochrobactrum anthropi and Ochrobactrum tritici, at operational condition of 500 mg N/L. The long term operation resulted in the decrease of nitrite oxidizers populations and this was probably the main factor contributing for the creation of conditions for the partial nitrification via nitrite to prevail during the operation at ammonium concentration of 500 mg N/L. The success in preventing free ammonia inhibition was attributed to the adoption of intermittent aeration and fed batch operation.