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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Bone Marrow Mononuclear Cell for Equine Joint Disease

Everett, James Blake 04 September 2020 (has links)
Osteoarthritis (OA) can be debilitating and career-ending for horses. Current treatments offer temporary and symptomatic relief, but potentially deleterious side effects. Bone marrow mononuclear cells (BMNC) are a rich source of macrophage progenitors that are anti-inflammatory and promote inflammation resolution. The objective of this study was to evaluate the ability of intra-articular BMNC therapy to improve clinical signs of naturally occurring equine OA. Horses presenting with clinical and radiographic evidence of moderate OA in a single joint were randomly assigned to 1 of 3 treatments: saline (negative control), triamcinolone (positive control), or BMNC (treatment group). Horses were subjectively and objectively evaluated for lameness and synovial fluid collected (cytology and cytokine/growth factor quantification) at 0, 7, and 21 days post-injection. Data were analyzed using General Estimating Equations with significance set at P<0.05. There were no adverse effects noted in any treatment group. No significant differences in synovial fluid cytology parameters, objective/subjective lameness scores, nor joint circumference were found between treatment groups at any time point. Within treatment groups, joint circumference did not change over time for saline- and triamcinolone-treated horses. However, joint circumference and objective lameness decreased significantly within BMNC-treated horses between Days 0 and 21 and Days 7 and 21. Lameness improved in saline-treated horses from 0 to 21 days, but did not improve in triamcinolone-treated horses. The decreased lameness and lack of adverse effects in the BMNC-treated horses in our study support a larger clinical trial using BMNC. / Master of Science / Osteoarthritis (OA) is a common source of joint pain in people and horses. Current treatments provide only partial and/or temporary relief. As a result, there is an urgent need for more effective and long-lasting treatment options. Arthritis is characterized by uncontrolled joint inflammation and progressive cartilage and bone destruction. Macrophages are cells within normal joints that function to resolve mild inflammation, maintaining joint health. However, when physiologic functions are overwhelmed, macrophages perpetuate inflammation through the recruitment of additional cell types to cope with the increased demands for repair. If this process is appropriately accomplished, macrophages resolve the inflammation, thereby enabling recovery and repair within the joint. Bone marrow aspirate is an excellent source of bone marrow-derived macrophage precursors (bone marrow mononuclear cells or BMNC) that have been shown to reduce joint inflammation and lameness in people and horses. The objective of our clinical trial was to evaluate the ability of intra-articular BMNC to improve clinical signs of naturally occurring OA in horses. BMNC treatment was compared to a placebo injection of saline and a standard-of-care in horses, corticosteroids. There were no adverse effects of BMNC treatment and BMNC-treated horses had significantly reduced joint circumference and lameness after 21 days. Synovial fluid cytology parameters did not differ significantly between treatment groups at any time point. In summary, BMNC are exciting because a horse can be treated with its own cells without the need for specialized equipment, and have the potential to naturally benefit thousands of people and horses suffering from arthritis.
12

Turning Round: Optimizing the Anti-Inflammatory Properties of Equine Bone Marrow Derived Mesenchymal Stem Cells for Osteoarthritis Through Three-Dimensional Culture

Bogers, Sophie Helen 19 April 2017 (has links)
Osteoarthritis (OA) is a degenerative disease of diarthrodial joints causing pain and loss of joint function. Etiology is heterogeneous, but commonly involves inflammation arising from impairment of normal tissue homeostasis and/or function. A cycle of low-grade inflammation and global tissue degradation causes alteration of tissue morphology and function via primary mechanisms or inability to withstand physiological forces. Current therapies variably ameliorate symptoms but do not modify progression. Mesenchymal stem cells (MSCs) have multi-modal properties but are ineffective in ameliorating equine OA. However, anti-inflammatory activities of bone marrow derived MSCs (BMSCs) are enhanced by three-dimensional spheroid culture so equine BMSC (eBMSC) spheroids could inhibit intra-articular inflammation. The overarching hypothesis is that eBMSCs can be enhanced to produce an allogeneic eBMSC therapy that inhibits intra-articular inflammation. In vitro experiments compared differences in anti-inflammatory phenotype between spheroid and traditionally cultured monolayer eBMSCs, the viability and health of eBMSC spheroids administered through needles, and the effects of allogeneic donor on the anti-inflammatory potential of eBMSC spheroids. A model of equine LPS induced synovitis was used to investigate anti-inflammatory efficacy of spheroid eBMSCs compared to placebo or monolayer eBMSCs in vivo. eBMSCs aggregate into spheroids that have stable stem cell marker expression with increased secretion and gene expression of IL-6 and PGE2, and gene expression of SDF-1 and TSG-6. IFN𝛾 and TNFα were not produced by eBMSC spheroids and IL-10 production varied between individuals. Spheroids maintain higher viability and lower senescence than monolayer eBMSCs after injection through a needle and form in high-throughput culture without detrimental effects on expression of TSG-6, IL-6 and PGE synthases that denote an anti-inflammatory phenotype. Additionally, there is significant variation in this phenotype depending on the eBMSC donor. eBMSC spheroids reduced total nucleated cell counts and objective lameness measurements at peak levels of intra-articular inflammation compared to monolayer cultured eBMSCs in vivo. In summary, spheroids increase anti-inflammatory potential of eBMSCs and are practical for clinical use. Increased anti-inflammatory efficacy was demonstrated in a model of in vivo inflammation. This dissertation provides an understanding of the anti-inflammatory activities of eBMSC spheroids that can be used to develop an OA therapy. / Ph. D.
13

Mechanical Comparison of a Type II External Skeletal Fixator and Locking Compression Plate in a Fracture Gap Model

Muro, Noelle Marie 16 June 2017 (has links)
The purpose of this study was to compare the stiffness of a Type II external skeletal fixator (ESF) to a 3.5 mm locking compression plate (LCP) in axial compression, mediolateral, and craniocaudal bending in a fracture gap model. The hypothesis was that the Type II ESF would demonstrate comparable stiffness to the LCP. A bone simulant consisting of short fiber reinforced epoxy cylinders and a 40 mm fracture gap was used. The LCP construct consisted of a 12 hole 3.5 mm plate with three 3.5 mm bicortical locking screws per fragment. The Type II ESF construct consisted of 3 proximal full fixation pins (Centerface®) per fragment in the mediolateral plane, and 2 carbon fiber connecting rods. Five constructs of each were tested in non-destructive mediolateral and craniocaudal bending, and axial compression. Stiffness was determined from the slope of the elastic portion of force-displacement curves. A one-way ANOVA and a Tukey-Kramer multiple comparisons test were performed, with significance defined as p < 0.05. In mediolateral bending, the stiffness of the Type II ESF (mean ± standard deviation; 1584.2 N/mm ± 202.8 N/mm) was significantly greater than that of the LCP (110.0 N/mm ± 13.4 N/mm). In axial compression, the stiffness of the Type II ESF (679.1 N/mm ± 20.1 N/mm) was significantly greater than that of the LCP (221.2 N/mm ± 19.1 N/mm). There was no significant difference between the constructs in craniocaudal bending. This information can aid in decision-making for fracture fixation, although ideal stiffness for healing remains unknown. / Master of Science
14

Mathematical models of bacteria population growth in bioreactors: formulation, phase space pictures, optimisation and control.

Strandberg, Per Erik January 2004 (has links)
<p>There are many types of bioreactors used for producing bacteria populations in commercial, medical and research applications. </p><p>This report presents a systematic discussion of some of the most important models corresponding to the well known reproduction kinetics such as the Michaelis-Menten kinetics, competitive substrate inhibition and competitive product inhibition. We propose a modification of a known model, analyze it in the same manner as known models and discuss the most popular types of bioreactors and ways of controlling them. </p><p>This work summarises much of the known results and may serve as an aid in attempts to design new models.</p>
15

Mathematical models of bacteria population growth in bioreactors: formulation, phase space pictures, optimisation and control.

Strandberg, Per Erik January 2004 (has links)
There are many types of bioreactors used for producing bacteria populations in commercial, medical and research applications. This report presents a systematic discussion of some of the most important models corresponding to the well known reproduction kinetics such as the Michaelis-Menten kinetics, competitive substrate inhibition and competitive product inhibition. We propose a modification of a known model, analyze it in the same manner as known models and discuss the most popular types of bioreactors and ways of controlling them. This work summarises much of the known results and may serve as an aid in attempts to design new models.
16

Factors associated with the initiation of biologic disease modifying antirheumatic drugs in Texas Medicaid patients with rheumatoid arthritis

Kim, Gilwan 10 October 2014 (has links)
Rheumatoid arthritis (RA) is a progressive autoimmune disorder of joints that is associated with high health care costs and yet lacks guidance on how early to initiate biologic disease-modifying antirheumatic drugs (DMARDs), a class of medications that is the major cost driver in RA management. The main purpose of this study was to examine patient socio-demographics, medication use patterns, and clinical characteristics associated with initiation of biologic DMARDs. This was a retrospective study using Texas Medicaid prescription and medical claims database during the study period of July 1, 2003 – December 31, 2010. Patients (18 – 63 years) with an RA diagnosis (ICD-9-CM code 714.xx), no non-biologic DMARD or biologic DMARD use during the pre-index period, and a minimum of 2 prescription claims for the same non-biologic DMARD during the post-index period were included in the study. The primary study outcomes were time to initiation of biologic DMARDs and likelihood of initiating biologic DMARDs. There was a total of 2,714 subjects included in the study. The majority had claims for pain medications (92.4%), glucocorticoids (64.9%), and non-biologic DMARD monotherapy (86.4%); while 24.3% initiated on biologic DMARDs and 58.9% had a Charlson Comorbidity Index (CCI) score=1. Compared to time to initiation (days) of biologic DMARDs for methotrexate (539.7±276.9) users, it was longer for sulfasalazine (670.2±167.8) and hydroxychloroquine (680.2±158.7) users and similar to leflunomide users (541.6±286.5; p<0.0001). There were no significant differences in time to initiation between non-biologic DMARD mono vs. dual therapy. Younger age, glucocorticoid use, methotrexate user (vs. sulfasalazine, hydroxychloroquine users), and non-biologic DMARD monotherapy user (vs. dual therapy user) were significantly associated with higher likelihood to initiate biologic DMARDs. In conclusion, age, glucocorticoid use, non-biologic DMARD type and therapy were significant factors associated with initiation of biologic DMARDs. Healthcare providers and Texas Medicaid should recognize these potential driving factors and take efforts to achieve optimal therapy for RA patients through thorough RA medication evaluation, well-structured RA monitoring programs, and patient education. / text
17

Uso tópico de bactérias predadoras reduz a destruição tecidual periodontal em ratos com periodontite experimental: estudo histológico, microtomográfico, imunológico e microbiológico / Topical use of predatory bacteria reduces periodontal tissue destruction in rats with experimental periodontitis: histological, microtomographic, immunological and microbiological study

Silva, Pedro Henrique Felix 26 April 2018 (has links)
Este estudo avaliou os efeitos da administração tópica de Bdellovibrio bacteriovorus HD100 na periodontite experimental em ratos. 32 ratos foram alocados nos grupos CT, DPT, CT-HD100 e DPT-HD100. No dia 0 do experimento, os animais dos grupos DPT e DPT-HD100 receberam ligaduras de seda ao redor dos primeiros molares inferiores (PMIs). Nos grupos CT-HD100 e DPT-HD100, suspensões de 1 mL contendo B. bacteriovorus HD100 foram administradas topicamente na região subgengival de PMIs nos dias 0, 3 e 7. Nos grupos CT e DPT, administrações tópicas foram realizadas com uma suspensão não contendo B. bacteriovorus HD100. Todos os animais foram submetidos à eutanásia no dia 14 do experimento. O tecido gengival, hemi-mandíbulas e biofilme bucal foram coletados para avaliação dos seguintes parâmetros: i) microarquitetura óssea, volume ósseo e nível ósseo alveolar (microtomografia computadorizada por transmissão de raios X micro-CT); ii) níveis de inserção conjuntiva (análise histomorfométrica); iii) microbiota bacteriana (checkerboard DNA-DNA hybridization); iv) expressão de citocinas inflamatórias e fatores de transcrição (análise imunoenzimática - Multiplex e reação em cadeia da polimerase por transcriptase reversa em tempo real); iii) padrão de imunomarcação para beta defensinas (BD), receptores do tipo Toll (TLR) e grupamentos de diferenciação (CD) (reações imunohistoquímicas). Testes in vitro foram também realizados para avaliar o potencial antimicrobiano de B. bacteriovorus HD100 contra periodontopatógenos. Os dados foram analisados estatisticamente (p < 0,05). O grupo DPT-HD100 apresentou menores porosidade óssea, separação trabecular, nível ósseo alveolar e nível de inserção conjuntiva, bem como maiores volume ósseo e número de trabéculas ósseas quando comparado ao Grupo DPT (p < 0,05). O grupo DPT-HD100 apresentou maiores proporções de espécies semelhantes à Actinomyces e Streptococcus e menores proporções de espécies semelhantes à Prevotella intermedia, Peptostreptococcus micros, Fusobacterium nucleatum, Fusobacterium polymorphum, Eikenella corrodens, Eubacterium nodatum, Campylobacter gracilis, Capnocytophaga sputigena e Veillonella parvula quando comparado ao Grupo DPT. Nas análises de parâmetros imunoinflamatórios, o Grupo DPT-HD100 apresentou maiores níveis de Proteina quimioatrativa de monócito1 (MCP-1), Células T normais expressas e secretadas, reguladas por ativação (RANTES), Osteoprotegerina (OPG), Fator de Crescimento Transformador (TGF)-&alpha; e Interleucina (IL)-10 e menores níveis de Fator de Necrose Tumoral (TNF)-&beta;, bem como maior padrão de imunomarcação para BD-1, BD-2 e BD-3 quando comparado ao Grupo DPT (p < 0,05). Para os níveis de IL-1, IL-6, Fator Estimulador de Colônias de Macrófagos (M-CSF), Ligante do Receptor Ativador de Fator Nuclear kappa-B (RANK-L) e padrões de imunomarcação para TLR-2, TLR-4, CD-4, CD-8 e CD-57, não foram observadas diferenças entre os grupos DPT e DPT-HD100. Na análise de expressão gênica, o Grupo DPT-HD100 apresentou maior expressão de IL-17, IL-10 e Forkhead box P3 (FOXP3) quando comparado ao Grupo DPT (p < 0,05). Nos testes in vitro, as co-culturas de periodontopatógenos (F. nucleatum, P. intermedia e A. ctinomycetemcomitans) e B. bacteriovorus HD100 apresentaram menor densidade óptica do que as culturas isoladas de periodontopatógenos em 48 horas. O uso tópico de B. bacteriovorus HD100 modifica os parâmetros imunoinflamatórios e microbiológicos, promovendo um efeito protetor contra a perda óssea alveolar e perda de inserção do tecido conjuntivo em ratos com periodontite experimental / This study evaluated the effects of topical administration of Bdellovibrio bacteriovorus HD100 on experimental periodontitis in rats. Thirty-two rats were allocated in the CT, DPT, CT-HD100 and DPT-HD100 groups. At day 0 of the experiment, animals of the DPT and DPT-HD100 groups received silk ligatures around the mandibular first molars (MFMs). In the CT-HD100 and DPT-HD100 groups, 1 ml suspensions containing B. bacteriovorus HD100 were topically administered in the subgingival region of MFMs on days 0, 3 and 7. In the CT and DPT groups, topical administrations were performed with a suspension without B. bacteriovorus HD100. All animals were submitted to euthanasia on day 14 of the experiment. The gingival tissue, hemi-mandibles and oral biofilm were collected to evaluate the following parameters: i) bone microarchiteture, bone volume and alveolar bone level (X-ray micro-computed tomography - micro-CT); ii) levels of conjunctive insertion (histomorphometric analysis); iii) microbiological profile (checkerboard DNA-DNA hybridization); iv) expression of inflammatory cytokines and transcription factors (immunoenzymatic analysis - Multiplex and Real-time reverse transcription polymerase chain reaction); iii) immunostaining pattern for Beta defensins (BD), Toll-like receptors (TLR) and Cluster of differentiation (CD) (immunohistochemical reactions). In vitro tests were also performed to evaluate the antimicrobial potential of B. bacteriovorus HD100 against periodontopathogens. The data were analyzed statistically (p <0.05). The DPT-HD100 Group presented lower bone porosity, trabecular separation, alveolar bone level and connective tissue attachment level, as well as higher bone volume and number of bone trabeculae when compared to the DPT Group (p <0.05). The DPT-HD100 Group presented higher proportions of Actinomyces and Streptococcus-like species and smaller proportions of Prevotella intermedia, Peptostreptococcus micros, Fusobacterium nucleatum, Fusobacterium polymorphum, Eikenella corrodens, Eubacterium nodatum, Campylobacter gracilis, Capnocytophaga sputigena and Veillonella parvula-like species when compared to the DPT Group. In the analysis of immunoinflammatory parameters, the DPT-HD100 Group presented higher levels of Monocyte-1 chemoattractant protein (MCP-1), Regulated on activation, normal T cell expressed and secreted (RANTES), Osteoprotegerin (OPG), Transforming Growth Factor (TGF)-&alpha; and Interleukin (IL) -10 and lower levels of Tumor Necrosis Factor (TNF)-&beta;, as well as a higher immunolabeling pattern for BD-1, BD-2 and BD-3 when compared to the DPT Group (p <0.05). For levels of IL-1, IL-6, Macrophage Colony Stimulating Factor (M-CSF), Receptor activator of nuclear factor kappa-B ligand (RANK-L) and immunolabeling patterns for TLR-2 TLR- 4, CD-4, CD-8 and CD-57, no differences were observed between the DPT and DPT-HD100 groups. In the analysis of gene expression, the DPT-HD100 group presented higher expression of IL-17, IL-10 and Forkhead box P3 (FOXP3) when compared to the DPT Group (p <0.05). In the in vitro tests, co-cultures of periodontopathogens (F. nucleatum, P. intermedia and A. ctinomycetemcomitans) and B. bacteriovorus HD100 showed lower optical density than isolated cultures of periodontopathogens at 48 hours. Topical use of B. bacteriovorus HD100 modifies immunoinflammatory and microbiological parameters, promoting a protective effect against alveolar bone loss and loss of connective tissue attachment in rats with experimental periodontitis
18

Avaliação do desenvolvimento da microbiota e da remoção de COT em filtros biologicamente ativos. / Evaluation of microbial growth and total organic carbon removal in biologically active filters.

Teixeira, Fernanda Tambelli 22 April 2008 (has links)
Este trabalho visa avaliar o desenvolvimento microbiano e a capacidade de degradação de carbono orgânico total (COT) em quatro colunas adsorvedoras pósfiltração, em escala de bancada, em três ensaios em batelada: o primeiro de longa duração (84 dias) com afluente de água filtrada clorada com baixa concentração de COT (1,4 mg/L); o segundo de longa duração (84 dias) com afluente de solução de glicose e água filtrada clorada com concentração de COT de 6,0 mg/L e o terceiro de curta duração (21 dias) e com o mesmo afluente utilizado no segundo teste. Foi utilizado carvão ativado granular (CAG) de mesmas características nas colunas adsorvedoras, exceto as faixas de diâmetros dos grânulos, que variaram de 0,5 a 0,71 mm (coluna 1A), de 0,84 a 1,0 mm (coluna 1B) e de 1,0 a 1,19 mm (coluna 1C) nas três colunas que tinham o diâmetro interno de 1,2 cm. A coluna 2, com diâmetro interno de 2,1 cm, recebeu CAG com grânulos na mesma faixa de diâmetros da coluna 1B (0,84 a 1,0 mm). As eficiências de remoção de COT no primeiro ensaio foram bem menores (46 a 74%) do que aquelas dos ensaios 2 (94 a 97%) e 3 (96 a 97%). Estes últimos apresentaram grande desenvolvimento da microbiota e elevadas eficiências de remoção de COT, devido ao co-metabolismo e biorregeneração nas colunas pela introdução da glicose. Nas três colunas de mesmo diâmetro, foi observado que quanto menor a faixa de diâmetros dos grânulos de CAG, maior foi o desenvolvimento da microbiota (expresso em contagens de bactérias heterotróficas); e nas colunas com mesma faixa de diâmetros de CAG e com diferentes diâmetros de coluna (1B e 2), o desenvolvimento da microbiota foi muito semelhante nos ensaios de longa duração. Com relação às eficiências de remoção de COT, não houve diferença significativa entre as quatro colunas nos ensaios de longa e curta duração com adição de glicose; no ensaio de longa duração sem adição de glicose as colunas 1A e 2 apresentaram melhores resultados em relação às demais e não há uma explicação clara para tal fato. / The major purpose of this experimental work was to evaluate the microbial development and the capabilities of degradation of Total Organic Carbon (TOC) of four post-filtration adsorption columns operated as batch reactors in three bench scale tests. The firs batch column testing was conducted by means of one long duration runs (84 days each) and the columns were fed with filtered, chlorinated water with low COT concentration (1.4 mg/L). The second batch column testing was conducted by means of one long duration runs (84 days each) and the columns were fed with a glucose and filtered chlorinated water solution (resulting TOC = 6.0 mg/L). The third batch column testing was conducted by means of one short duration runs (21 days each) and the columns were fed with the same solution of the second batch column testing. The same type of Granular Activated Carbon (GAC) was employed in all columns, except for the average granule diameter ranges. They were 0.5 to 0.71 mm (column 1A), 0.84 to 1.0 mm (column 1B), and 1.0 to 1.19 mm (column 1C), for the 12 mm diameter columns. The 21 mm diameter column 2 had CAG granules with the same size range of column 1B (0.84 to 1.0 mm). The TOC removal efficiencies in the first batch column testing were lower (46 to 74%) than 2 (94 to 97%) and 3 (96 to 97%) batch column testing. The lasts batch column testing led to high microbial growth and high TOC removal efficiencies due to cometabolism and bioregenation in the columns fed with a glucose. Regarding the three columns with the same diameter, it was observed that the lower the GAC granule size range, the higher the microbial growth rate (expressed as heterotrophic plate count); the columns with the same GAC size range but different column diameters (columns 1B and 2) the microbial growth rates were very similar with respect to the long period runs. With respect to the TOC removal efficiencies, there were no significant differences between the four columns in the long duration test runs and the short duration runs with glucose addition; in the long duration run without glucose addition, columns 1A and 2 were much more efficient at removing TOC than the other column; there is no clear explanation for it.
19

Růstové a proporční změny u dětí na ZŠ / Growth and Proportional Changes in Chidren at Grammar Schools

Zeťková, Marie January 2018 (has links)
This diploma thesis describes an anthropological survey of pupils in the 8th and 9th grades of certain primary schools in the Zlin Region (Czech Republic), pertaining to which the data thus obtained were subsequently processed and evaluated. The aim of the work was to analyse proportional changes and the biological maturity exhibited by the members of the probands through KEI, based on empirical data, in addition to determining the given somatotype according to the method of Heath & Carter (1967). ANTROPO 2000.2 software was utilized for processing the data. The findings of said research are compared with the data reported by the National Anthropological Survey (Czech Republic, 2001).
20

Avaliação do desenvolvimento da microbiota e da remoção de COT em filtros biologicamente ativos. / Evaluation of microbial growth and total organic carbon removal in biologically active filters.

Fernanda Tambelli Teixeira 22 April 2008 (has links)
Este trabalho visa avaliar o desenvolvimento microbiano e a capacidade de degradação de carbono orgânico total (COT) em quatro colunas adsorvedoras pósfiltração, em escala de bancada, em três ensaios em batelada: o primeiro de longa duração (84 dias) com afluente de água filtrada clorada com baixa concentração de COT (1,4 mg/L); o segundo de longa duração (84 dias) com afluente de solução de glicose e água filtrada clorada com concentração de COT de 6,0 mg/L e o terceiro de curta duração (21 dias) e com o mesmo afluente utilizado no segundo teste. Foi utilizado carvão ativado granular (CAG) de mesmas características nas colunas adsorvedoras, exceto as faixas de diâmetros dos grânulos, que variaram de 0,5 a 0,71 mm (coluna 1A), de 0,84 a 1,0 mm (coluna 1B) e de 1,0 a 1,19 mm (coluna 1C) nas três colunas que tinham o diâmetro interno de 1,2 cm. A coluna 2, com diâmetro interno de 2,1 cm, recebeu CAG com grânulos na mesma faixa de diâmetros da coluna 1B (0,84 a 1,0 mm). As eficiências de remoção de COT no primeiro ensaio foram bem menores (46 a 74%) do que aquelas dos ensaios 2 (94 a 97%) e 3 (96 a 97%). Estes últimos apresentaram grande desenvolvimento da microbiota e elevadas eficiências de remoção de COT, devido ao co-metabolismo e biorregeneração nas colunas pela introdução da glicose. Nas três colunas de mesmo diâmetro, foi observado que quanto menor a faixa de diâmetros dos grânulos de CAG, maior foi o desenvolvimento da microbiota (expresso em contagens de bactérias heterotróficas); e nas colunas com mesma faixa de diâmetros de CAG e com diferentes diâmetros de coluna (1B e 2), o desenvolvimento da microbiota foi muito semelhante nos ensaios de longa duração. Com relação às eficiências de remoção de COT, não houve diferença significativa entre as quatro colunas nos ensaios de longa e curta duração com adição de glicose; no ensaio de longa duração sem adição de glicose as colunas 1A e 2 apresentaram melhores resultados em relação às demais e não há uma explicação clara para tal fato. / The major purpose of this experimental work was to evaluate the microbial development and the capabilities of degradation of Total Organic Carbon (TOC) of four post-filtration adsorption columns operated as batch reactors in three bench scale tests. The firs batch column testing was conducted by means of one long duration runs (84 days each) and the columns were fed with filtered, chlorinated water with low COT concentration (1.4 mg/L). The second batch column testing was conducted by means of one long duration runs (84 days each) and the columns were fed with a glucose and filtered chlorinated water solution (resulting TOC = 6.0 mg/L). The third batch column testing was conducted by means of one short duration runs (21 days each) and the columns were fed with the same solution of the second batch column testing. The same type of Granular Activated Carbon (GAC) was employed in all columns, except for the average granule diameter ranges. They were 0.5 to 0.71 mm (column 1A), 0.84 to 1.0 mm (column 1B), and 1.0 to 1.19 mm (column 1C), for the 12 mm diameter columns. The 21 mm diameter column 2 had CAG granules with the same size range of column 1B (0.84 to 1.0 mm). The TOC removal efficiencies in the first batch column testing were lower (46 to 74%) than 2 (94 to 97%) and 3 (96 to 97%) batch column testing. The lasts batch column testing led to high microbial growth and high TOC removal efficiencies due to cometabolism and bioregenation in the columns fed with a glucose. Regarding the three columns with the same diameter, it was observed that the lower the GAC granule size range, the higher the microbial growth rate (expressed as heterotrophic plate count); the columns with the same GAC size range but different column diameters (columns 1B and 2) the microbial growth rates were very similar with respect to the long period runs. With respect to the TOC removal efficiencies, there were no significant differences between the four columns in the long duration test runs and the short duration runs with glucose addition; in the long duration run without glucose addition, columns 1A and 2 were much more efficient at removing TOC than the other column; there is no clear explanation for it.

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