Biofilm Models

The cells activities have been described based on a multi-species biofilm model, and the microbial kinetics by a mathematical model. Using this model predicts that the biomass on the external surface of the biofilm has higher activity than the biomass near the solid support surface, and that condition may occur, after the biofilm has reached a critical dept or formed... 

H2S production caused by the growth of sulfate-reducing bacteria in a biofilm in the reservoir rock close to the injection well (biofilm model)... 

The most sophisticated model available for predicting biodegradation of organic contaminants in subsurface systems is the biofilm model, presented by Williamson and McCarty149,150 which has been refined over several years by researchers at Stanford University and the University of Illinois/Urbana.151157... 

The biofilm model is based on two important features of the groundwater environment ... 

Williamson, K. and McCarty, P.L., Verification studies of the biofilm model for bacterial substrate utilization, J. Water Poll. Control Fed., 48, 281-296,1976. 

Details concerning biofilm growth and activity in sewers are at present not available to the same extent as is the case for the suspended biomass. Therefore, a simple expression for biofilm growth and respiration compared to other well-known deterministic biofilm models, e.g., as described by Gujer and Wanner (1990), is selected. 

One more factor must be considered before we summarize this foundation and discuss case histories the factor concept that could explain why hydrophilic polyurethane has shown an improved efficiency in development of biofllms. In a reconsideration of the biofilm model (Figure 5.4), let us consider a model in which the substratum has reservoir capacity (Figure 5.5). 

FIGURE 5.5 Biofilm model with absorptive substratiun. 

Sulfate Reduction in Lake Sediments A Biofilm Model... 

Hodgson RJ, Lynch RJM, Watson GK, Labarbe R, Treloar R, Allison C A continuous culture biofilm model of cariogenic responses. J Appl Microbiol 2001 90 440-448. 

A four-stage model has been used to describe the development of a bacterial biofilm. The stages comprise, first, primary attachment of cells to the underlying biomaterial, second, accumulation in multiple bacterial layers, third, maturation of the biofilm, and fourth, detachment of planktonic cells from the biofilm, which may then initiate a new cycle of biofilm formation elsewhere [11], In the staphylococci clear evidence exists for the attachment and accumulation/maturation stages of the biofilm model [12] (Fig. 1), while active detachment mechanisms are not well... 

Capdeville, B., Nguyen, K.M. and Rols, J.L., 1992, Biofilm modelling structural, reactional and diflusional aspects, in Melo, L.F., Bott, T.R., Fletcher, M. and Capdeville, B. eds. Biofilms - Science and Technology. Kluwer Academic Publishers, Dordrecht, 251 - 276. 

Many of the biofilm models described in this chapter resemble characteristics commonly found in human foreign-body infections, such as the estabUstiment of infection with low inoculum, persistence of infection without spontaneous healing, and relapse of disease soon after treatment. This sensitive and quantitative longitudinal monitoring approach is ideally suited to assess disease... 

The pseudohomogeneous biofilm model, given in Equs. 6.116 and 6.121, can be readily adapted to quantify the behavior of a rotating biological disk reactor. The setup of a similar balance equation for S using Monod-type kinetics yields for the case of rds kinetics... 

While types of biofilm model reactors have been summarized in Fig. 3.42,... 

TABLE 9.5 Conductivities of Several Materials Compared to the Conductivity Used in the Standard Case Shewanella oneidensis Biofilm Model. 

Percival, S.L., Bowler, P.G.,and Dolman, J. Antimicrobial activity of silver-containing dressings on wound microorganisms using an in vitro biofilm model. Int Wound J., 4, 186-191 (2007). 

Wanner O, Gujer W (1986) A multispecies biofilm model. Biotechnol Bioeng 28 314r-328... 

To begin developing a simple biofilm model based on kinetics, we first assume that bacterial growth is proportional to the concentration of bacteria, or... 

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