Acetone–butanol–ethanol(ABE)fermentation process can be exploited for the generation of butanol as biofuel,however it does need to overcome its low volumetric solvent productivity before it can commercially compete ...Acetone–butanol–ethanol(ABE)fermentation process can be exploited for the generation of butanol as biofuel,however it does need to overcome its low volumetric solvent productivity before it can commercially compete with fossil fuel technologies.In this regard,mathematical modelling and simulation analysis are tools that can serve as the base for process engineering development of biological systems.In this work,a novel phenomenological kinetic model of Clostridium acetobutylicum ATCC 824 was considered as a benchmark system to evaluate the behaviour of an ABE fermentation under different process configurations using both free and immobilized cells:single stage batch operation,fed-batch,single stage Continuous Stirred Tank Reactor(CSTR)and multistage CSTRs with and without biomass recirculation.The proposed model achieved a linear correlation index r^2=0.9952 and r^2=0.9710 over experimental data for free and immobilized cells respectively.The predicted maximum butanol concentration and productivity obtained were 13.08 g·L^(-1)and 1.9620 g·L^(-1)·h^(-1)respectively,which represents an increase of 1.01%and 990%versus the currently developed industrial scale process reported currently into the literature.These results provide a reliable platform for the design and optimization of the ABE fermentation system and showcase the adequate predictive nature of the proposed model.展开更多
We present a droplet-based microfluidic system that enables CRISPR-based gene editing and high-throughput screening on a chip.The microfluidic device contains a 10x10 element array,and each element contains sets of el...We present a droplet-based microfluidic system that enables CRISPR-based gene editing and high-throughput screening on a chip.The microfluidic device contains a 10x10 element array,and each element contains sets of electrodes for two electric field-actuated operations:electrowetting for merging droplets to mix reagents and electroporation for transformation.This device can perform up to 100 genetic modification reactions in parallel,providing a scalable platform for generating the large number of engineered strains required for the combinatorial optimization of genetic pathways and predictable bioengineering.We demonstrate the system's capabilities through the CRISPR-based engineering of two test cases:(1)disruption of the function of the enzyme galactokinase(galK)in£coli and(2)targeted engineering of the glutamine synthetase gene(glnA)and the blue-pigment synthetase gene(bpsA)to improve indigoidine production in£coli.展开更多
This study deals with constant-gain adaptive observers for nonlinear systems,for which relatively few solutions are available for some particular cases.We introduce an asymptotic observer of constant gain for nonlinea...This study deals with constant-gain adaptive observers for nonlinear systems,for which relatively few solutions are available for some particular cases.We introduce an asymptotic observer of constant gain for nonlinear systems that have linear input.This allows the observer design to be formulated within the linear matrix inequality paradigm provided that a strictly positive real condition bet ween the inpu t disturbance and the output is fulfilled.The proposed observer is t hen applied to a large class of nonlinear chemos tat dynamical systems that are widely used in the fermentation process,cell cultures,medicine,etc.In fact,under standard practical assumptions,the necessary change of the chemos tat state coordinates exis ts,allowing use of the const ant-gain observer.Finally,the developed theory is illustrated by estimating pollutant concentration in a Spirulina maxima wastewater treatment facility.展开更多
基金financial support via the postgraduate scholarship No.277760
文摘Acetone–butanol–ethanol(ABE)fermentation process can be exploited for the generation of butanol as biofuel,however it does need to overcome its low volumetric solvent productivity before it can commercially compete with fossil fuel technologies.In this regard,mathematical modelling and simulation analysis are tools that can serve as the base for process engineering development of biological systems.In this work,a novel phenomenological kinetic model of Clostridium acetobutylicum ATCC 824 was considered as a benchmark system to evaluate the behaviour of an ABE fermentation under different process configurations using both free and immobilized cells:single stage batch operation,fed-batch,single stage Continuous Stirred Tank Reactor(CSTR)and multistage CSTRs with and without biomass recirculation.The proposed model achieved a linear correlation index r^2=0.9952 and r^2=0.9710 over experimental data for free and immobilized cells respectively.The predicted maximum butanol concentration and productivity obtained were 13.08 g·L^(-1)and 1.9620 g·L^(-1)·h^(-1)respectively,which represents an increase of 1.01%and 990%versus the currently developed industrial scale process reported currently into the literature.These results provide a reliable platform for the design and optimization of the ABE fermentation system and showcase the adequate predictive nature of the proposed model.
基金supported by the Basque Government through the BERC 2014-2017 program and the Spanish Ministry of Economy and Competitiveness MINECO through the BCAM Severo Ochoa excellence accreditation SEV-2013-0323Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia,LLC,a wholly owned subsidiary of Honeywell International,Inc.,for the U.S.Department of Energy's National Nuclear Security Administration under contract DE-NA-0003525.
文摘We present a droplet-based microfluidic system that enables CRISPR-based gene editing and high-throughput screening on a chip.The microfluidic device contains a 10x10 element array,and each element contains sets of electrodes for two electric field-actuated operations:electrowetting for merging droplets to mix reagents and electroporation for transformation.This device can perform up to 100 genetic modification reactions in parallel,providing a scalable platform for generating the large number of engineered strains required for the combinatorial optimization of genetic pathways and predictable bioengineering.We demonstrate the system's capabilities through the CRISPR-based engineering of two test cases:(1)disruption of the function of the enzyme galactokinase(galK)in£coli and(2)targeted engineering of the glutamine synthetase gene(glnA)and the blue-pigment synthetase gene(bpsA)to improve indigoidine production in£coli.
基金This research was partly supported by the Czech Science Foundation(No.GA19-05872S)。
文摘This study deals with constant-gain adaptive observers for nonlinear systems,for which relatively few solutions are available for some particular cases.We introduce an asymptotic observer of constant gain for nonlinear systems that have linear input.This allows the observer design to be formulated within the linear matrix inequality paradigm provided that a strictly positive real condition bet ween the inpu t disturbance and the output is fulfilled.The proposed observer is t hen applied to a large class of nonlinear chemos tat dynamical systems that are widely used in the fermentation process,cell cultures,medicine,etc.In fact,under standard practical assumptions,the necessary change of the chemos tat state coordinates exis ts,allowing use of the const ant-gain observer.Finally,the developed theory is illustrated by estimating pollutant concentration in a Spirulina maxima wastewater treatment facility.
