检索结果-内蒙古大学图书馆

作者： Busschaert, Pieter Geeraerd, Annemie H. Uyttendaele, Mieke Van Impe, Jan F. CPMF2 - Flemish Cluster Predictive Microbiology in Foods Belgium Department of Chemical Engineering BioTeC - Chemical and Biochemical Process Technology and Control Katholieke Universiteit Leuven Leuven Belgium MeBioS - Division of Mechatronics Biostatistics and Sensors Katholieke Universiteit Leuven Leuven Belgium Department of Food Safety and Food Quality Laboratory of Food Microbiology and Food Preservation Ghent University Ghent Belgium

ISBN: (纸本)9783902661708

Quantitative microbiological risk assessment aims at estimating the risk of illness that is related to a certain pathogen and food type combination through the use of simulations. A recent trend can be seen in which uncertainty about the risk estimate is characterized separately from variability, generally implemented by means of a two-dimensional Monte Carlo simulation. This research aims at identifying the key parameters that contribute to the obtained risk while keeping the effect of uncertainty and variability separated using a methodology based on analysis of variance. The risk related to Listeria monocytogenes in meat preparations is used as a case study. It is found that uncertainty about the correct dose-response model is determining the output most. Also the variability distribution of storage duration and storage temperature have a major effect on the final risk. Furthermore, uncertainty about the location of the storage duration distribution is an important factor determining risk. These findings illustrate how the methodology proposed in this research enables identification of the relative importance of all model parameters such as temperature, storage duration, food contamination, etc., and also comparison of the impact of variability versus uncertainty about model parameters on the final risk estimate. © 2010 IFAC.

关键词： Sensitivity analysis

来源：评论

学校读者我要写书评

暂无评论

Individual-based Modelling of Non-motile Bacterial Colony Formation In Structured Foods: A Comparative Study

引用

IFAC Proceedings Volumes 2010年第6期43卷 329-334页

作者： A.J. Verhulst A.M. Cappuyns E. Van Derlinden K. Bernaerts J.F.M. Van Impe CPMF - Flemish Cluster Predictive Microbiology in Foods www.cpmf2.be Chemical and Biochemical Process Technology and Control (BioTeC) Dept. of Chemical Engineering Katholieke Universiteit Leuven W. de Croylaan 46 3001 Heverlee Belgium

Microbial dynamics in structured food products differ from microbial dynamics in liquids. In structured products, microorganisms are immobilised and constrained to grow as colonies, as opposed to liquid, where bacteria grow planktonically, i.e., dispersed or free-living. Little information is available on the displacement mechanisms within colony formation of non-motile bacteria. Three displacement mechanisms can be found in literature, i.e., (i) a discrete cellular automaton (CA) mechanism, (ii) a moving boundary mechanism, and (iii) a shoving mechanism. All three mechanisms are implemented in an individual-based modelling (IbM) environment. Advantages and disadvantages of each approach with respect to the individualbased modelling approach are summarised. The discrete CA results in the least realistic colony formation, but has the advantage of great computational speed. Both the moving boundary and the shoving mechanism produce biologically realistic results, albeit at a different level of detail for the representation of the environment. Both are suitable for IbM implementation and the choice depends on the level of detail necessary to describe the microbial phenomena under study.

关键词： predictive microbiology cellular automaton individual-based modelling submerged colony dynamics bacterial movement

来源：评论

学校读者我要写书评

暂无评论

Modeling microbial kinetics as a function of temperature: identification of the growth/inactivation interface

引用

IFAC Proceedings Volumes 2010年第6期43卷 519-524页

作者： E. Van Derlinden J.F. Van Impe CPMF2 - Flemish Cluster Predictive Microbiology in Foods -www.cpmf2.be BioTeC - Chemical and Biochemical Process Technology and Control Department of Chemical Engineering Katholieke Universiteit Leuven W. de Croylaan 46 B-3001 Leuven Belgium

A previous implementation of dynamic experiments for the estimation of the parameters of the Cardinal Temperature Model with Inflection (CTMI), which describes the temperature effect on the microbial growth rate, revealed that the maximum growth temperature ( T max ) can only be estimated accurately when temperatures close to the true T max are included. As such, a reliable T max estimate is required at the beginning of the OED/PE implementation. Here, alternative experiments in which the temperature exceeds the growth/inactivation interface are evaluated. Results from the simulation study show that the accuracy and reliability of the T max estimate depends on the selected temperature profile. A very accurate and realistic T max value is obtained from experiments with an initial temperature slightly lower than the true T max . When the dynamic temperature starts at temperatures above T max , a larger uncertainty and variability is observed. From this, it can be concluded that information with respect to growth at temperatures close to T max is required for an accurate and reliable T max estimate. In a second step, two dynamic temperature profiles are implemented in a computer controlled bioreactor. The experimental data do not result in an accurate and reliable estimation of T max . Additional dynamic experiments are required to evaluate the proposed experimental set-up.

关键词： predictive microbiology maximum growth temperature cardinal temperature model dynamic experiments growth/inactivation interface parameter estimation

来源：评论

学校读者我要写书评

暂无评论

Sensitivity Analysis of a Two-dimensional Microbiological Risk Assessment

引用

IFAC Proceedings Volumes 2010年第6期43卷 323-328页

作者： Pieter Busschaert Annemie H. Geeraerd Mieke Uyttendaele Jan F. Van Impe CPMF2 - Flemish Cluster Predictive Microbiology in Foods -http://www.cpmf2.be BioTeC - Chemical and Biochemical Process Technology and Control Department of Chemical Engineering Katholieke Universiteit Leuven Leuven Belgium MeBioS - Division of Mechatronics Biostatistics and Sensors Department of Biosystems (BIOSYST) Katholieke Universiteit Leuven Leuven Belgium Laboratory of Food Microbiology and Food Preservation Department of Food Safety and Food Quality Ghent University Ghent Belgium

关键词： Quantitative microbiological risk assessment sensitivity analysis variability uncertainty analysis of variance L. monocytogenes meat preparations

来源：评论

学校读者我要写书评

暂无评论

Quantification of MTBE and TBA biodegradation

引用

IFAC Proceedings Volumes 2010年第6期43卷 513-518页

作者： Astrid M. Cappuyns Linde J. Debor Ilse Y. Smets Dirk Springael Leen Bastiaens Jan F. Van Impe BioTeC - Chemical and Biochemical Process Technology and Control Katholieke Universiteit Leuven W. de Croylaan 46 B-3001 Leuven (Belgium) Tel: +32-16-32.14.66 Fax: +32-16-32.29.91 Separation and Conversion Technology Vlaamse instelling voor technologisch onderzoek (VITO) Boeretang 200 B-2400 Mol (Belgium) Division Soil and Water Management Katholieke Universiteit Leuven Kasteelpark Arenberg 20 B-3001 Leuven (Belgium)

Methyl tertiary butyl ether or MTBE is often used as an additive in gasoline to boost the octane rating and to promote more efficient combustion of the gasoline. This widespread use of MTBE has resulted in serious soil and groundwater pollution. To tackle MTBE contamination in groundwater, bioremediation is considered a cost-effective and energy-efficient option. The design of an efficient, reliable and reproducible bioremediation strategy requires a thorough understanding of the (microbial) degradation kinetics of both MTBE and TBA (tertiary butyl alcohol), i.e., the main intermediate during bioremediation of MTBE. To assist the design procedure, this research focuses on building a low complexity, yet accurate mathematical model to describe MTBE/TBA degradation kinetics by a bacterial consortium, i.e., the VITO M-consortium. The resulting model provides an accurate description of MTBE/TBA degradation and has successfully been validated on independent experimental data. Since the model is of the mass balance type, it can easily be extended to other types of operation by defining the transport terms of the new system. This makes the model a very useful tool in the design procedure for large scale bioremediation strategies. Furthermore, the model provides insight in the MTBE/TBA degradation kinetics and biodegradation mechanisms by hypothesis testing.

关键词： mass balance type models biodegradation kinetics macroscopic model methyl tertiary butyl ether (MTBE) tertiary butyl alcohol (TBA)

来源：评论

学校读者我要写书评

暂无评论

Describing the heterogeneous heat response of E. coli with a subpopulation type model

Describing the heterogeneous heat response of E. coli with a...

引用

15th IFAC Symposium on System Identification, SYSID 2009

作者： Van Derlinden, E. Van Impe, J.F. BioTeC - Chemical and Biochemical Process Technology and Control Section Department of Chemical Engineering Katholieke Universiteit Leuven W. de Croylaan 46 B-3001 Leuven Belgium

ISBN: (纸本)9783902661470

Previous work showed that the exponential growth phase of E. coli K12 MG1655, grown in Brain Heart Infusion broth at temperatures close to its maximum temperature for growth is disturbed. Based on plate count data, microscopic images and literature, the existence of a heat resistant subpopulation was hypothesized [21]. This hypothesis is here mathematically validated by means of a heterogeneous modeling approach. Two subpopulations are considered: one sensitive population and one population with increased heat tolerance. A large fraction of the initial population inactivates while the remaining smaller fraction is able to resist (or adapt to) the inimical temperature and grows. A heterogeneous model that encloses growth (resistant population) and inactivation (sensitive population) is used to describe the global population dynamics. Most experimental data can be predicted when taking into account parameter uncertainty via Monte Carlo simulation. The heterogeneous modeling approach yields accurate description of disturbed growth curves at super optimal temperatures, except for high initial cell densities. This study confirms the existence of a (small) heat resistant subpopulation in typical inoculum cultures of Escherichia coli K12 MG1655. © 2009 IFAC.

关键词： Escherichia coli

来源：评论

学校读者我要写书评

暂无评论

Describing the heterogeneous heat response of E. coli with a subpopulation type model

引用

IFAC Proceedings Volumes 2009年第10期42卷 1253-1258页

作者： E. Van Derlinden J.F. Van Impe BioTeC - Chemical and Biochemical Process Technology and Control Section Department of Chemical Engineering Katholieke Universiteit Leuven W. de Croylaan 46 B-3001 Leuven (Belgium)

关键词： system identification complex systems models parameter estimation Monte Carlo simulation

来源：评论

学校读者我要写书评

暂无评论

Nitrite effect on the phosphorus uptake activity of phosphate accumulating organisms (PAOs) in pilot-scale SBR and MBR reactors

Nitrite effect on the phosphorus uptake activity of phosphat...

引用

作者： Sin, Gürkan Niville, Kwinten Bachis, Giulia Jiang, Tao Nopens, Ingmar Van Hulle, Stijn Vanrolleghem, Peter A. BIOMATH Department of Applied Mathematics Biometrics and Process Control Ghent University Coupure Links 653 B-9000 Gent Belgium Department of Chemical and Biochemical Engineering Technical University of Denmark Building 229DK-2800 Kgs. Lyngby Denmark Research group EnBiChem Department of Industrial Engineering and Technology University College West Flanders Graaf Karel De Goedelaan 5 8500 Kortrijk Belgium ModelEAU Département de Génie Civil Pavillon Pouliot Université Laval QC G1K 7P4 Canada

Batch tests were performed to investigate the nitrite effect on the P-uptake of biomass grown in pilot-scale SBR and MBR systems. The results showed that the nitrite has an inhibitory effect on the aerobic P-uptake of the SBR and the MBR biomasses. The degree of inhibition was observed to be 65 % and 37 % at 10 mg NO2-N/l for the SBR and the MBR respectively. Both biomasses were found capable of using nitrite as electron acceptor as effectively as nitrate. Moreover, for the SBR biomass the anoxic P-uptake rate using nitrite was found even higher (60%) than the P-uptake rate with nitrate. From a modelling point of view, the current models require appropriate extensions to describe these various effects of nitrite. Hence, an extension of the ASM2d model has been provided. Prevention of nitrite build-up in full-scale EBPRs will eliminate the nitrite inhibition problem. Alternatively one can adopt a proactive approach in which the aerobic P-uptake phase is replaced with an anoxic P-uptake phase using only nitrite as electron acceptor. Such an approach offers considerable cost savings and enhanced nitrogen and phosphorus removal. This, however, requires further research for experimental validation and testing.

关键词： Biomass

来源：评论

学校读者我要写书评

暂无评论

Model for growth and AI-2 type quorum sensing of Salmonella Typhimurium sl1344 10th

Model for growth and AI-2 type quorum sensing of Salmonella ...

引用

10th IFAC Symposium on Computer Applications in Biotechnology, 2007

作者： Cappuyns, Astrid M. Bernaerts, Kristel De Keersmaecker, Sigrid C. Vanderleyden, Jos Van Impe, Jan F. Chemical and Biochemical Process Technology and Control Section Katholieke Universiteit Leuven W. de Croylaan 46 LeuvenB-3001 Belgium Centre of Microbial and Plant Genetics Katholieke Universiteit Leuven Kasteelpark Arenberg 20 LeuvenB-3001 Belgium

ISBN: (纸本)9783902661616

The last decades, the research on cell-cell communication or quorum sensing has been quite intense. Bacterial communication allows bacteria to coordinate their behavior and to act as one entity. Quorum sensing controls microbiological functions of medical, agricultural and industrial importance and a better understanding of the underlying mechanisms and the conditions under which the signaling occurs, offers possibilities for new applications. In this paper the production of the AI-2 signaling molecule by Salmonella Typhimurium is investigated in a controlled environment (bioreactor). The experimental results are applied to build a macroscopic model that describes the evolution of the AI-2 production and uptake by Salmonella Typhimurium in relation to the growth kinetics and biomass concentration. Copyright © 2007 IF AC.

关键词： Bioreactors

来源：评论

学校读者我要写书评

暂无评论

MODEL FOR GROWTH AND AI-2 TYPE QUORUM SENSING OF SALMONELLA TYPHIMURIUM SL1344

引用

IFAC Proceedings Volumes 2007年第4期40卷 207-212页

作者： Astrid M. Cappuyns Kristel Bernaerts Sigrid C. De Keersmaecker Jos Vanderleyden Jan F. Van Impe Chemical and Biochemical Process Technology and Control Section Katholieke Universiteit Leuven W. de Croylaan 46 B-3001 Leuven Belgium Centre of Microbial and Plant Genetics Katholieke Universiteit Leuven Kasteelpark Arenberg 20 B-3001 Leuven Belgium

关键词： Salmonella Typhimurium bioreactor quorum sensing overflow metabolism macroscopic model

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：