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Sample records for cell production model

  1. Modelling the Performance of Product Integrated Photovoltaic (PIPV) Cells Indoors

    NARCIS (Netherlands)

    Apostolou, G.; Verwaal, M.; Reinders, Angelina H.M.E.

    2014-01-01

    In this paper we present a model, which have been developed for the estimation of the PV products’ cells’ performance in an indoor environment. The model computes the efficiency and power production of PV technologies, as a function of distance from natural and artificial light sources. It intents

  2. A Simplified Model of Glycoprotein Production within Cell Culture

    OpenAIRE

    Lambert, A. B.; Smith, F. T.; Velayudhan, A.

    2017-01-01

    Complex biological products, such as those used to treat various forms of cancer, are typically produced by mammalian cells in bioreactors. The most important class of such biological medicines is proteins. These typically bind to sugars (glycans) in a process known as glycosylation, creating glycoproteins, which are more stable and effective medicines. The glycans are large polymers that are formed by a long sequence of enzyme catalysed reactions. This sequence is not always completed, thus ...

  3. Kinetic modeling of cell metabolism for microbial production.

    Science.gov (United States)

    Costa, Rafael S; Hartmann, Andras; Vinga, Susana

    2016-02-10

    Kinetic models of cellular metabolism are important tools for the rational design of metabolic engineering strategies and to explain properties of complex biological systems. The recent developments in high-throughput experimental data are leading to new computational approaches for building kinetic models of metabolism. Herein, we briefly survey the available databases, standards and software tools that can be applied for kinetic models of metabolism. In addition, we give an overview about recently developed ordinary differential equations (ODE)-based kinetic models of metabolism and some of the main applications of such models are illustrated in guiding metabolic engineering design. Finally, we review the kinetic modeling approaches of large-scale networks that are emerging, discussing their main advantages, challenges and limitations. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Progesterone production requires activation of caspase-3 in preovulatory granulosa cells in a serum starvation model.

    Science.gov (United States)

    An, Li-Sha; Yuan, Xiao-Hua; Hu, Ying; Shi, Zi-Yun; Liu, Xiao-Qin; Qin, Li; Wu, Gui-Qing; Han, Wei; Wang, Ya-Qin; Ma, Xu

    2012-11-01

    Granulosa cells proliferate, differentiate, and undergo apoptosis throughout follicular development. Previous studies have demonstrated that stimulation of progesterone production is accompanied by caspase-3 activation. Moreover, we previously reported that arsenic enhanced caspase-3 activity coupled with progesterone production. Inhibition of caspase-3 activity can significantly inhibit progesterone production induced by arsenic or follicle-stimulating hormone (FSH). Here, we report that serum starvation induces caspase-3 activation coupled with augmentation of progesterone production. Serum starvation also increased the levels of cytochrome P450 cholesterol side chain cleavage enzyme (P450scc) and steroidogenic acute regulatory (StAR) protein, both of which may contribute to progesterone synthesis in preovulatory granulosa cells. Inhibition of caspase-3 activity resulted in a decrease in progesterone production. Deactivation of caspase-3 activity by caspase-3 specific inhibitor also resulted in decreases in P450scc and StAR expression, which may partly contribute to the observed decrease in progesterone production. Our study demonstrates for the first time that progesterone production in preovulatory granulosa cells is required for caspase-3 activation in a serum starvation model. Inhibition of caspase-3 activity can result in decreased expression of the steroidogenic proteins P450scc and StAR. Our work provides further details on the relationship between caspase-3 activation and steroidogenesis and indicates that caspase-3 plays a critical role in progesterone production by granulosa cells. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. First complete and productive cell culture model for members of the genus Iridovirus.

    Science.gov (United States)

    D'Costa, Susan M; Vigerust, David J; Perales-Hull, Marsha R; Lodhi, Sundus A; Viravathana, Polrit; Bilimoria, Shän L

    2012-11-01

    Chilo iridescent virus (CIV; the type strain of the genus Iridovirus) replicates productively in larvae of the boll weevil, Anthonomus grandis. This study focuses on characterizing productive infections of a boll weevil cell line, BRL-AG-3A (AG3A), starting with CIV reared in the waxworm, Galleria mellonella. We show that CIV can be continually and productively passaged to high titer in AG3A cells. The replication of larval-derived CIV in AG3A was analyzed by observing viral DNA replication and restriction endonuclease digestion profiles, morphogenesis, and infectivity using TCID(50) assays with AG3A as an indicator cell line. The data showed that virus passaged in the AG3A host is stable. AG3A cells are more efficient than previously utilized CF-124T cells from Choristoneura fumiferana. This system constitutes a superior model for cellular and molecular studies on CIV; it represents the first complete, productive cell culture model for the replication of CIV or any member of the genus Iridovirus.

  6. CFD Model Of A Planar Solid Oxide Electrolysis Cell For Hydrogen Production From Nuclear Energy

    International Nuclear Information System (INIS)

    Grant L. Hawkes; James E. O'Brien; Carl M. Stoots; J. Stephen Herring

    2005-01-01

    A three-dimensional computational fluid dynamics (CFD) model has been created to model high temperature steam electrolysis in a planar solid oxide electrolysis cell (SOEC). The model represents a single cell as it would exist in an electrolysis stack. Details of the model geometry are specific to a stack that was fabricated by Ceramatec2, Inc. and tested at the Idaho National Laboratory. Mass, momentum, energy, and species conservation and transport are provided via the core features of the commercial CFD code FLUENT2. A solid-oxide fuel cell (SOFC) model adds the electrochemical reactions and loss mechanisms and computation of the electric field throughout the cell. The FLUENT SOFC user-defined subroutine was modified for this work to allow for operation in the SOEC mode. Model results provide detailed profiles of temperature, Nernst potential, operating potential, anode-side gas composition, cathode-side gas composition, current density and hydrogen production over a range of stack operating conditions. Mean model results are shown to compare favorably with experimental results obtained from an actual ten-cell stack tested at INL

  7. Evaluation of Stem Cell-Derived Red Blood Cells as a Transfusion Product Using a Novel Animal Model.

    Science.gov (United States)

    Shah, Sandeep N; Gelderman, Monique P; Lewis, Emily M A; Farrel, John; Wood, Francine; Strader, Michael Brad; Alayash, Abdu I; Vostal, Jaroslav G

    2016-01-01

    Reliance on volunteer blood donors can lead to transfusion product shortages, and current liquid storage of red blood cells (RBCs) is associated with biochemical changes over time, known as 'the storage lesion'. Thus, there is a need for alternative sources of transfusable RBCs to supplement conventional blood donations. Extracorporeal production of stem cell-derived RBCs (stemRBCs) is a potential and yet untapped source of fresh, transfusable RBCs. A number of groups have attempted RBC differentiation from CD34+ cells. However, it is still unclear whether these stemRBCs could eventually be effective substitutes for traditional RBCs due to potential differences in oxygen carrying capacity, viability, deformability, and other critical parameters. We have generated ex vivo stemRBCs from primary human cord blood CD34+ cells and compared them to donor-derived RBCs based on a number of in vitro parameters. In vivo, we assessed stemRBC circulation kinetics in an animal model of transfusion and oxygen delivery in a mouse model of exercise performance. Our novel, chronically anemic, SCID mouse model can evaluate the potential of stemRBCs to deliver oxygen to tissues (muscle) under resting and exercise-induced hypoxic conditions. Based on our data, stem cell-derived RBCs have a similar biochemical profile compared to donor-derived RBCs. While certain key differences remain between donor-derived RBCs and stemRBCs, the ability of stemRBCs to deliver oxygen in a living organism provides support for further development as a transfusion product.

  8. Mammalian Cell Culture Process for Monoclonal Antibody Production: Nonlinear Modelling and Parameter Estimation

    Directory of Open Access Journals (Sweden)

    Dan Selişteanu

    2015-01-01

    Full Text Available Monoclonal antibodies (mAbs are at present one of the fastest growing products of pharmaceutical industry, with widespread applications in biochemistry, biology, and medicine. The operation of mAbs production processes is predominantly based on empirical knowledge, the improvements being achieved by using trial-and-error experiments and precedent practices. The nonlinearity of these processes and the absence of suitable instrumentation require an enhanced modelling effort and modern kinetic parameter estimation strategies. The present work is dedicated to nonlinear dynamic modelling and parameter estimation for a mammalian cell culture process used for mAb production. By using a dynamical model of such kind of processes, an optimization-based technique for estimation of kinetic parameters in the model of mammalian cell culture process is developed. The estimation is achieved as a result of minimizing an error function by a particle swarm optimization (PSO algorithm. The proposed estimation approach is analyzed in this work by using a particular model of mammalian cell culture, as a case study, but is generic for this class of bioprocesses. The presented case study shows that the proposed parameter estimation technique provides a more accurate simulation of the experimentally observed process behaviour than reported in previous studies.

  9. Models and methods for design and implementation of computer based control and monitoring systems for production cells

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen Birk

    This dissertation is concerned with the engineering, i.e. the designing and making, of industrial cell control systems. The focus is on automated robot welding cells in the shipbuilding industry. The industrial research project defines models and methods for design and implementation of computer...... through the implementation of two cell control systems for robot welding cells in production at Odense Steel Shipyard.It is concluded that cell control technology provides for increased performance in production systems, and that the Cell Control Engineering concept reduces the effort for providing high...... quality and high functionality cell control solutions for the industry....

  10. Evaluation of Stem Cell-Derived Red Blood Cells as a Transfusion Product Using a Novel Animal Model.

    Directory of Open Access Journals (Sweden)

    Sandeep N Shah

    Full Text Available Reliance on volunteer blood donors can lead to transfusion product shortages, and current liquid storage of red blood cells (RBCs is associated with biochemical changes over time, known as 'the storage lesion'. Thus, there is a need for alternative sources of transfusable RBCs to supplement conventional blood donations. Extracorporeal production of stem cell-derived RBCs (stemRBCs is a potential and yet untapped source of fresh, transfusable RBCs. A number of groups have attempted RBC differentiation from CD34+ cells. However, it is still unclear whether these stemRBCs could eventually be effective substitutes for traditional RBCs due to potential differences in oxygen carrying capacity, viability, deformability, and other critical parameters. We have generated ex vivo stemRBCs from primary human cord blood CD34+ cells and compared them to donor-derived RBCs based on a number of in vitro parameters. In vivo, we assessed stemRBC circulation kinetics in an animal model of transfusion and oxygen delivery in a mouse model of exercise performance. Our novel, chronically anemic, SCID mouse model can evaluate the potential of stemRBCs to deliver oxygen to tissues (muscle under resting and exercise-induced hypoxic conditions. Based on our data, stem cell-derived RBCs have a similar biochemical profile compared to donor-derived RBCs. While certain key differences remain between donor-derived RBCs and stemRBCs, the ability of stemRBCs to deliver oxygen in a living organism provides support for further development as a transfusion product.

  11. From Product Models to Product State Models

    DEFF Research Database (Denmark)

    Larsen, Michael Holm

    1999-01-01

    A well-known technology designed to handle product data is Product Models. Product Models are in their current form not able to handle all types of product state information. Hence, the concept of a Product State Model (PSM) is proposed. The PSM and in particular how to model a PSM is the Research...

  12. Quantitative intracellular flux modeling and applications in biotherapeutic development and production using CHO cell cultures.

    Science.gov (United States)

    Huang, Zhuangrong; Lee, Dong-Yup; Yoon, Seongkyu

    2017-12-01

    Chinese hamster ovary (CHO) cells have been widely used for producing many recombinant therapeutic proteins. Constraint-based modeling, such as flux balance analysis (FBA) and metabolic flux analysis (MFA), has been developing rapidly for the quantification of intracellular metabolic flux distribution at a systematic level. Such methods would produce detailed maps of flows through metabolic networks, which contribute significantly to better understanding of metabolism in cells. Although these approaches have been extensively established in microbial systems, their application to mammalian cells is sparse. This review brings together the recent development of constraint-based models and their applications in CHO cells. The further development of constraint-based modeling approaches driven by multi-omics datasets is discussed, and a framework of potential modeling application in cell culture engineering is proposed. Improved cell culture system understanding will enable robust developments in cell line and bioprocess engineering thus accelerating consistent process quality control in biopharmaceutical manufacturing. © 2017 Wiley Periodicals, Inc.

  13. Production models

    DEFF Research Database (Denmark)

    Svensson, Carsten

    2002-01-01

    The Project is co-financed with Nilpeter A/S and investigates the industrialization of build to order production. Project content: - Enterprise engineering - Specification processes - Mass Customization/ Build To Order - Knowledge/information management - Configuration - Supply Chain Management...

  14. Experimental and in silico modelling analyses of the gene expression pathway for recombinant antibody and by-product production in NS0 cell lines.

    Science.gov (United States)

    Mead, Emma J; Chiverton, Lesley M; Spurgeon, Sarah K; Martin, Elaine B; Montague, Gary A; Smales, C Mark; von der Haar, Tobias

    2012-01-01

    Monoclonal antibodies are commercially important, high value biotherapeutic drugs used in the treatment of a variety of diseases. These complex molecules consist of two heavy chain and two light chain polypeptides covalently linked by disulphide bonds. They are usually expressed as recombinant proteins from cultured mammalian cells, which are capable of correctly modifying, folding and assembling the polypeptide chains into the native quaternary structure. Such recombinant cell lines often vary in the amounts of product produced and in the heterogeneity of the secreted products. The biological mechanisms of this variation are not fully defined. Here we have utilised experimental and modelling strategies to characterise and define the biology underpinning product heterogeneity in cell lines exhibiting varying antibody expression levels, and then experimentally validated these models. In undertaking these studies we applied and validated biochemical (rate-constant based) and engineering (nonlinear) models of antibody expression to experimental data from four NS0 cell lines with different IgG4 secretion rates. The models predict that export of the full antibody and its fragments are intrinsically linked, and cannot therefore be manipulated individually at the level of the secretory machinery. Instead, the models highlight strategies for the manipulation at the precursor species level to increase recombinant protein yields in both high and low producing cell lines. The models also highlight cell line specific limitations in the antibody expression pathway.

  15. MODELS FOR MOUSE CHIMERA PRODUCTION: AGGREGATION OF ES CELLS WITH CLEAVAGE STAGE EMBRYOS

    Directory of Open Access Journals (Sweden)

    STANCA CLAUDIA

    2007-01-01

    Full Text Available In a mutant ES cells↔ wild-type embryo chimera, ES cells behave more like epiblastcells. They can contribute to the primitive ectoderm layers, which give rise to all theembryonic tissues and some extraembryonic tissues (Beddington and Robertson,1989, but not to trophectoderm or primitive endoderm. Using transgenic ES celllines, aggregated with cleavage stage host embryo, ES cells can integrate randomlyin the embryo proper. If they will be take part in the formation of ICM (inner cellmass, it will be possible to obtain germline chimera animals. To generate ES cells↔ cleavage stage host embryo chimeras, we used (CD-1 mice as donors of hostembryos as well as recipients of manipulated embryos. For chimera production, weused fluorescent-labeled ES cell line (CD1/EGFP, because in this case we canfollow the fate of ES cells during the embryonic development. We produced thechimers using “aggregation chimera technique”. 8 cells stage zona pellucida free,mouse embryos were aggregated in an aggregation plates, with a clump of ES cells(10 – 15 cells. The chimera embryos were cultivated for 24 hours in the incubator(at 37 °C, 5% CO2 in air. The chimera blastocysts resulted after cultivation, weretransferred to the uterus of the 2.5-dpc pseudo pregnant females.

  16. MODELS FOR MOUSE CHIMERA PRODUCTION: AGGREGATION OF ES CELLS WITH CLEAVAGE STAGE EMBRYOS

    Directory of Open Access Journals (Sweden)

    CLAUDIA STANCA

    2007-05-01

    Full Text Available In a mutant ES cells↔ wild-type embryo chimera, ES cells behave more like epiblastcells. They can contribute to the primitive ectoderm layers, which give rise to all theembryonic tissues and some extraembryonic tissues (Beddington and Robertson,1989, but not to trophectoderm or primitive endoderm. Using transgenic ES celllines, aggregated with cleavage stage host embryo, ES cells can integrate randomlyin the embryo proper. If they will be take part in the formation of ICM (inner cellmass, it will be possible to obtain germline chimera animals. To generate ES cells↔ cleavage stage host embryo chimeras, we used (CD-1 mice as donors of hostembryos as well as recipients of manipulated embryos. For chimera production, weused fluorescent-labeled ES cell line (CD1/EGFP, because in this case we canfollow the fate of ES cells during the embryonic development. We produced thechimers using “aggregation chimera technique”. 8 cells stage zona pellucida free,mouse embryos were aggregated in an aggregation plates, with a clump of ES cells(10 – 15 cells. The chimera embryos were cultivated for 24 hours in the incubator(at 37 °C, 5% CO2 in air. The chimera blastocysts resulted after cultivation, weretransferred to the uterus of the 2.5-dpc pseudo pregnant females.

  17. Horizontal bioreactor for ethanol production by immobilized cells. Pt. 3. Reactor modeling and experimental verification

    Energy Technology Data Exchange (ETDEWEB)

    Woehrer, W

    1989-04-05

    A mathematical model which describes ethanol formation in a horizontal tank reactor containing Saccharomyces cerevisiae immobilized in small beads of calcium alignate has been developed. The design equations combine flow dynamics of the reactor as well as product formation kinetics. The model was verified for 11 continuous experiments, where dilution rate, feed glucose concentration and bead volume fraction were varied. The model predicts effluent ethanol concentration and CO/sub 2/ production rate within the experimental error. A simplification of the model is possible, when the feed glucose concentration does not exceed 150 kg/m/sup 3/. The simplification results in an analytical solution of the design equation and hence can easily be applied for design purposes as well as for optimization studies.

  18. Model-directed engineering of "difficult-to-express" monoclonal antibody production by Chinese hamster ovary cells.

    Science.gov (United States)

    Pybus, Leon P; Dean, Greg; West, Nathan R; Smith, Andrew; Daramola, Olalekan; Field, Ray; Wilkinson, Stephen J; James, David C

    2014-02-01

    Despite improvements in volumetric titer for monoclonal antibody (MAb) production processes using Chinese hamster ovary (CHO) cells, some "difficult-to-express" (DTE) MAbs inexplicably reach much lower process titers. These DTE MAbs require intensive cell line and process development activity, rendering them more costly or even unsuitable to manufacture. To rapidly and rationally identify an optimal strategy to improve production of DTE MAbs, we have developed an engineering design platform combining high-yielding transient production, empirical modeling of MAb synthesis incorporating an unfolded protein response (UPR) regulatory loop with directed expression and cell engineering approaches. Utilizing a panel of eight IgG1 λ MAbs varying >4-fold in volumetric titer, we showed that MAb-specific limitations on folding and assembly rate functioned to induce a proportionate UPR in host CHO cells with a corresponding reduction in cell growth rate. Derived from comparative empirical modeling of cellular constraints on the production of each MAb we employed two strategies to increase production of DTE MAbs designed to avoid UPR induction through an improvement in the rate/cellular capacity for MAb folding and assembly reactions. Firstly, we altered the transfected LC:HC gene ratio and secondly, we co-expressed a variety of molecular chaperones, foldases or UPR transactivators (BiP, CypB, PDI, and active forms of ATF6 and XBP1) with recombinant MAbs. DTE MAb production was significantly improved by both strategies, although the mode of action was dependent upon the approach employed. Increased LC:HC ratio or CypB co-expression improved cell growth with no effect on qP. In contrast, BiP, ATF6c and XBP1s co-expression increased qP and reduced cell growth. This study demonstrates that expression-engineering strategies to improve production of DTE proteins in mammalian cells should be product specific, and based on rapid predictive tools to assess the relative impact of

  19. A stochastic step model of replicative senescence explains ROS production rate in ageing cell populations.

    Directory of Open Access Journals (Sweden)

    Conor Lawless

    Full Text Available Increases in cellular Reactive Oxygen Species (ROS concentration with age have been observed repeatedly in mammalian tissues. Concomitant increases in the proportion of replicatively senescent cells in ageing mammalian tissues have also been observed. Populations of mitotic human fibroblasts cultured in vitro, undergoing transition from proliferation competence to replicative senescence are useful models of ageing human tissues. Similar exponential increases in ROS with age have been observed in this model system. Tracking individual cells in dividing populations is difficult, and so the vast majority of observations have been cross-sectional, at the population level, rather than longitudinal observations of individual cells.One possible explanation for these observations is an exponential increase in ROS in individual fibroblasts with time (e.g. resulting from a vicious cycle between cellular ROS and damage. However, we demonstrate an alternative, simple hypothesis, equally consistent with these observations which does not depend on any gradual increase in ROS concentration: the Stochastic Step Model of Replicative Senescence (SSMRS. We also demonstrate that, consistent with the SSMRS, neither proliferation-competent human fibroblasts of any age, nor populations of hTERT overexpressing human fibroblasts passaged beyond the Hayflick limit, display high ROS concentrations. We conclude that longitudinal studies of single cells and their lineages are now required for testing hypotheses about roles and mechanisms of ROS increase during replicative senescence.

  20. A stochastic step model of replicative senescence explains ROS production rate in ageing cell populations.

    Science.gov (United States)

    Lawless, Conor; Jurk, Diana; Gillespie, Colin S; Shanley, Daryl; Saretzki, Gabriele; von Zglinicki, Thomas; Passos, João F

    2012-01-01

    Increases in cellular Reactive Oxygen Species (ROS) concentration with age have been observed repeatedly in mammalian tissues. Concomitant increases in the proportion of replicatively senescent cells in ageing mammalian tissues have also been observed. Populations of mitotic human fibroblasts cultured in vitro, undergoing transition from proliferation competence to replicative senescence are useful models of ageing human tissues. Similar exponential increases in ROS with age have been observed in this model system. Tracking individual cells in dividing populations is difficult, and so the vast majority of observations have been cross-sectional, at the population level, rather than longitudinal observations of individual cells.One possible explanation for these observations is an exponential increase in ROS in individual fibroblasts with time (e.g. resulting from a vicious cycle between cellular ROS and damage). However, we demonstrate an alternative, simple hypothesis, equally consistent with these observations which does not depend on any gradual increase in ROS concentration: the Stochastic Step Model of Replicative Senescence (SSMRS). We also demonstrate that, consistent with the SSMRS, neither proliferation-competent human fibroblasts of any age, nor populations of hTERT overexpressing human fibroblasts passaged beyond the Hayflick limit, display high ROS concentrations. We conclude that longitudinal studies of single cells and their lineages are now required for testing hypotheses about roles and mechanisms of ROS increase during replicative senescence.

  1. Introduction to solar cell production

    International Nuclear Information System (INIS)

    Kim, Gyeong Hae; Lee, Jun Sin

    2009-08-01

    This book introduces solar cell production. It is made up eight chapters, which are summary of solar cell with structure and prospect of the business, special variable of solar cell on light of the sun and factor causing variable of solar cell, production of solar cell with surface texturing, diffusion, metal printing dry and firing and edge isolation, process of solar cell on silicone wafer for solar cell, forming of electrodes, introduction of thin film solar cell on operating of solar cell, process of production and high efficiency of thin film solar cell, sorting of solar cell and production with background of silicone solar cell and thin film solar cell, structure and production of thin film solar cell and compound solar cell, introduction of solar cell module and the Industrial condition and prospect of solar cell.

  2. Homogenization, lyophilization or acid-extraction of meat products improves iron uptake from cereal-meat product combinations in an in vitro digestion/Caco-2 cell model.

    Science.gov (United States)

    Pachón, Helena; Stoltzfus, Rebecca J; Glahn, Raymond P

    2009-03-01

    The effect of processing (homogenization, lyophilization, acid-extraction) meat products on iron uptake from meat combined with uncooked iron-fortified cereal was evaluated using an in vitro digestion/Caco-2 cell model. Beef was cooked, blended to create smaller meat particles, and combined with electrolytic iron-fortified infant rice cereal. Chicken liver was cooked and blended, lyophilized, or acid-extracted, and combined with FeSO4-fortified wheat flour. In the beef-cereal combination, Caco-2 cell iron uptake, assessed by measuring the ferritin formed by cells, was greater when the beef was blended for the greatest amount of time (360 s) compared with 30 s (P meat products on iron absorption in iron-fortified cereals.

  3. Maillard reaction products from highly heated food prevent mast cell number increase and inflammation in a mouse model of colitis.

    Science.gov (United States)

    Al Amir, Issam; Dubayle, David; Héron, Anne; Delayre-Orthez, Carine; Anton, Pauline M

    2017-12-01

    Links between food and inflammatory bowel diseases (IBDs) are often suggested, but the role of food processing has not been extensively studied. Heat treatment is known to cause the loss of nutrients and the appearance of neoformed compounds such as Maillard reaction products. Their involvement in gut inflammation is equivocal, as some may have proinflammatory effects, whereas other seem to be protective. As IBDs are associated with the recruitment of immune cells, including mast cells, we raised the hypothesis that dietary Maillard reaction products generated through heat treatment of food may limit the colitic response and its associated recruitment of mast cells. An experimental model of colitis was used in mice submitted to mildly and highly heated rodent food. Adult male mice were divided in 3 groups and received nonheated, mildly heated, or highly heated chow during 21 days. In the last week of the study, each group was split into 2 subgroups, submitted or not (controls) to dextran sulfate sodium (DSS) colitis. Weight variations, macroscopic lesions, colonic myeloperoxidase activity, and mucosal mast cell number were evaluated at the end of the experiment. Only highly heated chow significantly prevented DSS-induced weight loss, myeloperoxidase activity, and mast cell number increase in the colonic mucosa of DSS-colitic mice. We suggest that Maillard reaction products from highly heated food may limit the occurrence of inflammatory phases in IBD patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Progress toward forecasting product quality and quantity of mammalian cell culture processes by performance-based modeling.

    Science.gov (United States)

    Schmidberger, Timo; Posch, Christoph; Sasse, Alexandra; Gülch, Carina; Huber, Robert

    2015-01-01

    The production of biopharmaceuticals requires highly sophisticated, complex cell based processes. Once a process has been developed, acceptable ranges for various control parameters are typically defined based on process characterization studies often comprising several dozens of small scale bioreactor cultivations. A lot of data is generated during these studies and usually only the information needed to define acceptable ranges is processed in more detail. Making use of the wealth of information contained in such data sets, we present here a methodology that uses performance data (such as metabolite profiles) to forecast the product quality and quantity of mammalian cell culture processes based on a toolbox of advanced statistical methods. With this performance based modeling (PBM) the final product concentration and 12 quality attributes (QAs) for two different biopharmaceutical products were predicted in daily intervals throughout the main stage process. The best forecast was achieved for product concentration in a very early phase of the process. Furthermore, some glycan isoforms were predicted with good accuracy several days before the bioreactor was harvested. Overall, PBM clearly demonstrated its capability of early process endpoint prediction by only using commonly available data, even though it was not possible to predict all QAs with the desired accuracy. Knowing the product quality prior to the harvest allows the manufacturer to take counter measures in case the forecasted quality or quantity deviates from what is expected. This would be a big step towards real-time release, an important element of the FDA's PAT initiative. © 2015 American Institute of Chemical Engineers.

  5. Modeling and optimization of proton-conducting solid oxide electrolysis cell: Conversion of CO2 into value-added products

    Science.gov (United States)

    Namwong, Lawit; Authayanun, Suthida; Saebea, Dang; Patcharavorachot, Yaneeporn; Arpornwichanop, Amornchai

    2016-11-01

    Proton-conducting solid oxide electrolysis cells (SOEC-H+) are a promising technology that can utilize carbon dioxide to produce syngas. In this work, a detailed electrochemical model was developed to predict the behavior of SOEC-H+ and to prove the assumption that the syngas is produced through a reversible water gas-shift (RWGS) reaction. The simulation results obtained from the model, which took into account all of the cell voltage losses (i.e., ohmic, activation, and concentration losses), were validated using experimental data to evaluate the unknown parameters. The developed model was employed to examine the structural and operational parameters. It is found that the cathode-supported SOEC-H+ is the best configuration because it requires the lowest cell potential. SOEC-H+ operated favorably at high temperatures and low pressures. Furthermore, the simulation results revealed that the optimal S/C molar ratio for syngas production, which can be used for methanol synthesis, is approximately 3.9 (at a constant temperature and pressure). The SOEC-H+ was optimized using a response surface methodology, which was used to determine the optimal operating conditions to minimize the cell potential and maximize the carbon dioxide flow rate.

  6. Piscirickettsia salmonis Imbalances the Innate Immune Response to Succeed in a Productive Infection in a Salmonid Cell Line Model.

    Directory of Open Access Journals (Sweden)

    Claudio A Álvarez

    Full Text Available Piscirickettsia salmonis is a facultative intracellular bacterium that causes the disease called "salmon rickettsial syndrome". Attempts to control this disease have been unsuccessful, because existing vaccines have not achieved the expected effectiveness and the antibiotics used fail to completely eradicate the pathogen. This is in part the product of lack of scientific information that still lacks on the mechanisms used by this bacterium to overcome infected-cell responses and survive to induce a productive infection in macrophages. For that, this work was focused in determining if P. salmonis is able to modify the expression and the imbalance of IL-12 and IL-10 using an in vitro model. Additionally, we also evaluated the role the antimicrobial peptide hepcidin had in the control of this pathogen in infected cells. Therefore, the expression of IL-10 and IL-12 was evaluated at earlier stages of infection in the RTS11 cell line derived from Oncorhynchus mykiss macrophages. Simultaneously, the hepcidin expression and location was analyzed in the macrophages infected with the pathogen. Our results suggest that IL-10 is clearly induced at early stages of infection with values peaking at 36 hours post infection. Furthermore, infective P. salmonis downregulates the expression of antimicrobial peptide hepcidin and vesicles containing this peptide were unable to merge with the infective bacteria. Our results suggest that P. salmonis is able to manipulate the behavior of host cytokines and likely might constitute a virulence mechanism that promotes intracellular bacterial replication in leukocytes cells lines of trout and salmon. This mechanism involves the generation of an optimum environment for the microorganism and the downregulation of antimicrobial effectors like hepcidin.

  7. Product and Process Modelling

    DEFF Research Database (Denmark)

    Cameron, Ian T.; Gani, Rafiqul

    . These approaches are put into the context of life cycle modelling, where multiscale and multiform modelling is increasingly prevalent in the 21st century. The book commences with a discussion of modern product and process modelling theory and practice followed by a series of case studies drawn from a variety......This book covers the area of product and process modelling via a case study approach. It addresses a wide range of modelling applications with emphasis on modelling methodology and the subsequent in-depth analysis of mathematical models to gain insight via structural aspects of the models...... to biotechnology applications, food, polymer and human health application areas. The book highlights to important nature of modern product and process modelling in the decision making processes across the life cycle. As such it provides an important resource for students, researchers and industrial practitioners....

  8. Modelling and simulation of a U-loop Reactor for Single Cell Protein Production

    DEFF Research Database (Denmark)

    Wu, Mengzhe; Huusom, Jakob Kjøbsted; Gernaey, Krist

    2016-01-01

    In this work, two approaches of modelling a one phase U-loop reactor are presented. A simple CSTR model consisting of first-principles dynamic process equations was implemented in Matlab. The results give a good indication of the basic understanding of the effect of changing operation conditions...

  9. Product Platform Modeling

    DEFF Research Database (Denmark)

    Pedersen, Rasmus

    for customisation of products. In many companies these changes in the business environment have created a controversy between the need for a wide variety of products offered to the marketplace and a desire to reduce variation within the company in order to increase efficiency. Many companies use the concept...... other. These groups can be varied and combined to form different product variants without increasing the internal variety in the company. Based on the Theory of Domains, the concept of encapsulation in the organ domain is introduced, and organs are formulated as platform elements. Included......This PhD thesis has the title Product Platform Modelling. The thesis is about product platforms and visual product platform modelling. Product platforms have gained an increasing attention in industry and academia in the past decade. The reasons are many, yet the increasing globalisation...

  10. Red blood cell production

    Science.gov (United States)

    ... bone marrow of bones. Stem cells in the red bone marrow called hemocytoblasts give rise to all of the formed elements in blood. If a hemocytoblast commits to becoming a cell called a proerythroblast, it will develop into a new red blood cell. The formation of a red blood ...

  11. Production process reproducibility and product quality consistency of transient gene expression in HEK293 cells with anti-PD1 antibody as the model protein.

    Science.gov (United States)

    Ding, Kai; Han, Lei; Zong, Huifang; Chen, Junsheng; Zhang, Baohong; Zhu, Jianwei

    2017-03-01

    Demonstration of reproducibility and consistency of process and product quality is one of the most crucial issues in using transient gene expression (TGE) technology for biopharmaceutical development. In this study, we challenged the production consistency of TGE by expressing nine batches of recombinant IgG antibody in human embryonic kidney 293 cells to evaluate reproducibility including viable cell density, viability, apoptotic status, and antibody yield in cell culture supernatant. Product quality including isoelectric point, binding affinity, secondary structure, and thermal stability was assessed as well. In addition, major glycan forms of antibody from different batches of production were compared to demonstrate glycosylation consistency. Glycan compositions of the antibody harvested at different time periods were also measured to illustrate N-glycan distribution over the culture time. From the results, it has been demonstrated that different TGE batches are reproducible from lot to lot in overall cell growth, product yield, and product qualities including isoelectric point, binding affinity, secondary structure, and thermal stability. Furthermore, major N-glycan compositions are consistent among different TGE batches and conserved during cell culture time.

  12. Investigation of the performance of fermentation processes using a mathematical model including effects of metabolic bottleneck and toxic product on cells.

    Science.gov (United States)

    Sriyudthsak, Kansuporn; Shiraishi, Fumihide

    2010-11-01

    A number of recent research studies have focused on theoretical and experimental investigation of a bottleneck in a metabolic reaction network. However, there is no study on how the bottleneck affects the performance of a fermentation process when a product is highly toxic and remarkably influences the growth and death of cells. The present work therefore studies the effect of bottleneck on product concentrations under different product toxicity conditions. A generalized bottleneck model in a fed-batch fermentation is constructed including both the bottleneck and the product influences on cell growth and death. The simulation result reveals that when the toxic product strongly influences the cell growth and death, the final product concentration is hardly changed even if the bottleneck is removed, whereas it is markedly changed by the degree of product toxicity. The performance of an ethanol fermentation process is also discussed as a case example to validate this result. In conclusion, when the product is highly toxic, one cannot expect a significant increase in the final product concentration even if removing the bottleneck; rather, it may be more effective to somehow protect the cells so that they can continuously produce the product. Copyright © 2010 Elsevier Inc. All rights reserved.

  13. Modelling Retail Floorspace Productivity

    NARCIS (Netherlands)

    A.R. Thurik (Roy); P. Kooiman

    1986-01-01

    textabstractThis research note presents a "switching regime" model to investigate the impact of environmental factors on floorspace productivity of individual retail stores. The model includes independent supply and demand functions, which are incorporated within a sales maximizing framework. Unlike

  14. Huh-7 cell line as an alternative cultural model for the production of human like erythropoietin (EPO

    Directory of Open Access Journals (Sweden)

    Kausar Humera

    2011-11-01

    Full Text Available Abstract Background and Aims Erythropoietin (EPO is a glycoprotein hormone which is required to regulate the production of red blood cells. Deficiency of EPO is known to cause anemia in chronically infected renal patients and they require regular blood transfusion. Availability of recombinant EPO has eliminated the need for blood transfusion and now it is extensively used for the treatment of anemia. Glycosylation of erythropoietin is essential for its secretion, stability, protein conformation and biological activity. However, maintenance of human like glycosylation pattern during manufacturing of EPO is a major challenge in biotechnology. Currently, Chinese hamster ovary (CHO cell line is used for the commercial production of erythropoietin but this cell line does not maintain glycosylation resembling human system. With the trend to eliminate non-human constituent from biopharmaceutical products, as a preliminary approach, we have investigated the potential of human hepatoma cell line (Huh-7 to produce recombinant EPO. Materials and methods Initially, the secretory signal and Kozak sequences was added before the EPO mature protein sequence using overlap extension PCR technique. PCR-amplified cDNA fragments of EPO was inserted into mammalian expression vector under the control of the cytomegalovirus (CMV promoter and transiently expressed in CHO and Huh-7 cell lines. After RT-PCR analysis, ELISA and Western blotting was performed to verify the immunochemical properties of secreted EPO. Results Addition of secretory signal and Kozak sequence facilitated the extra-cellular secretion and enhanced the expression of EPO protein. Significant expression (P Conclusion Huh-7 cell line has a great potential to produce glycosylated EPO, suggesting the use of this cell line to produce glycoproteins of the therapeutic importance resembling to the natural human system.

  15. Innovation Production Models

    Directory of Open Access Journals (Sweden)

    Tamam N. Guseinova

    2016-01-01

    Full Text Available The article is dedicated to the study of the models of production of innovations at enterprise and state levels. The shift towards a new technology wave induces a change in systems of division of labour as well as establishment of new forms of cooperation that are reflected both in theory and practice of innovation policy and management. Within the scope of the research question we have studied different generation of innovation process, starting with simple linear models - "technology push" and "market pull" - and ending with a complex integrated model of open innovations. There are two organizational models of innovation production at the enterprise level: start-ups in the early stages of their development and ambidextrous organizations. The former are prone to linear models of innovation process, while the latter create innovation within more sophisticated inclusive processes. Companies that effectuate reciprocal ambidexterity stand out from all the rest, since together with start-ups, research and development centres, elements of innovation infrastructure and other economic agents operating in the same value chain they constitute the core of most advanced forms of national innovation systems, namely Triple Helix and Quadruple Helix systems. National innovation systems - models of innovation production at the state level - evolve into systems with a more profound division of labour that enable "line production" of innovations. These tendencies are closely related to the advent and development of the concept of serial entrepreneurship that transforms entrepreneurship into a new type of profession. International experience proves this concept to be efficient in various parts of the world. Nevertheless, the use of above mentioned models and concepts in national innovation system should be justified by socioeconomic conditions of economic regions, since they determine the efficiency of implementation of certain innovation processes and

  16. [Strategic considerations on the design and choice of animal models for non-clinical investigations of cell-based medicinal products].

    Science.gov (United States)

    Lehmann, Jörg; Schulz, Ronny M; Sanzenbacher, Ralf

    2015-11-01

    For the development of medicinal products animal models are still indispensable to demonstrate efficacy and safety prior to first use in humans. Advanced therapy medicinal products (ATMP), which include cell-based medicinal products (CBMP), differ in their pharmacology and toxicology compared to conventional pharmaceuticals, and thus, require an adapted regime for non-clinical development. Developers are, therefore, challenged to develop particular individual concepts and to reconcile these with regulatory agencies. Guidelines issued by the European Medicines Agency (EMA), the U.S. Food and Drug Administration (FDA) and other sources can provide direction.The published approaches for non-clinical testing of efficacy document that homologous animal models where the therapeutic effect is investigated in a disease-relevant animal model utilizing cells derived from the same species are commonly used. The challenge is that the selected model should reflect the human disease in all critical features and that the cells should be comparable to the investigated human medicinal product in terms of quality and biological activity. This is not achievable in all cases. In these cases, alternative methods may provide supplemental information. To demonstrate the scientific proof-of-concept (PoC), small animal models such as mice or rats are preferred. During the subsequent product development phase, large animal models (i.e. sheep, minipigs, dogs) must be considered, as they may better reflect the anatomical or physiological situation in humans. In addition to efficacy, those models may also be suitable to prove some safety aspects of ATMP (e.g. regarding dose finding, local tolerance, or undesired interactions and effects of the administered cells in the target tissue). In contrast, for evaluation of the two prominent endpoints for characterizing the safety of ATMP (i.e. biodistribution, tumorigenicity) heterologous small animal models, especially immunodeficient mouse strains

  17. Product Knowledge Modelling and Management

    DEFF Research Database (Denmark)

    Zhang, Y.; MacCallum, K. J.; Duffy, Alex

    1996-01-01

    function-oriented design. Both Specific Product Knowledge and Product Domain Knowledge are modelled at two levels, a meta-model and an information-level.Following that, a computer-based scheme to manage the proposed product lknowledge models within a dynamically changing environment is presented.......The term, Product Knowledge is used to refer to two related but distinct concepts; the knowledge of a specific product (Specific Product Knowledge) and the knowledge of a product domain (Product Domain Knowledge). Modelling and managing Product Knowlege is an essential part of carrying out design.......A scheme is presented in this paper to model, i.e. classify, structure and formalise the product knowledge for the purpose of supporting function-oriented design. The product design specification and four types of required attributes of a specific product have been identified to form the Specific Product...

  18. Radiobilogical cell survival models

    International Nuclear Information System (INIS)

    Zackrisson, B.

    1992-01-01

    A central issue in clinical radiobiological research is the prediction of responses to different radiation qualities. The choice of cell survival and dose-response model greatly influences the results. In this context the relationship between theory and model is emphasized. Generally, the interpretations of experimental data depend on the model. Cell survival models are systematized with respect to their relations to radiobiological theories of cell kill. The growing knowlegde of biological, physical, and chemical mechanisms is reflected in the formulation of new models. The present overview shows that recent modelling has been more oriented towards the stochastic fluctuations connected to radiation energy deposition. This implies that the traditional cell surivival models ought to be complemented by models of stochastic energy deposition processes and repair processes at the intracellular level. (orig.)

  19. Methamphetamine decreases CD4 T cell frequency and alters pro-inflammatory cytokine production in a model of drug abuse

    Science.gov (United States)

    Mata, Mariana M.; Napier, T. Celeste; Graves, Steven M.; Mahmood, Fareeha; Raeisi, Shohreh; Baum, Linda L.

    2015-01-01

    The reason co-morbid methamphetamine use and HIV infection lead to more rapid progression to AIDS is unclear. We used a model of methamphetamine self-administration to measure the effect of methamphetamine on the systemic immune system to better understand the comorbidity of methamphetamine and HIV. Catheters were implanted into the jugular veins of male, Sprague Dawley rats so they could self-administer methamphetamine (n = 18) or be given saline (control; n = 16) for 14 days. One day after the last self-administration session, blood and spleens were collected. We measured serum levels of pro-inflammatory cytokines, intracellular IFN-γand TNF-α, and frequencies of CD4+, CD8+, CD200+ and CD11b/c+ lymphocytes in the spleen. Rats that self-administer methamphetamine had a lower frequency of CD4+ T cells, but more of these cells produced IFN-γ. Methamphetamine did not alter the frequency of TNF-α-producing CD4+ T cells. Methamphetamine using rats had a higher frequency of CD8+ T cells, but fewer of them produced TNF-α. CD11b/c and CD200 expression were unchanged. Serum cytokine levels of IFN-γ, TNF-α and IL-6 in methamphetamine rats were unchanged. Methamphetamine lifetime dose inversely correlated with serum TNF-α levels. Or data suggest that methamphetamine abuse may exacerbate HIV disease progression by activating CD4 T cells, making them more susceptible to HIV infection, and contributing to their premature demise. Methamphetamine may also increase susceptibility to HIV infection, explaining why African American men who have sex with men (MSM) and frequently use methamphetamine are at the highest risk of HIV infection. PMID:25678251

  20. Methamphetamine decreases CD4 T cell frequency and alters pro-inflammatory cytokine production in a model of drug abuse.

    Science.gov (United States)

    Mata, Mariana M; Napier, T Celeste; Graves, Steven M; Mahmood, Fareeha; Raeisi, Shohreh; Baum, Linda L

    2015-04-05

    The reason co-morbid methamphetamine use and HIV infection lead to more rapid progression to AIDS is unclear. We used a model of methamphetamine self-administration to measure the effect of methamphetamine on the systemic immune system to better understand the co-morbidity of methamphetamine and HIV. Catheters were implanted into the jugular veins of male, Sprague Dawley rats so they could self-administer methamphetamine (n=18) or be given saline (control; n=16) for 14 days. One day after the last operant session, blood and spleens were collected. We measured serum levels of pro-inflammatory cytokines, intracellular IFN-γ and TNF-α, and frequencies of CD4(+), CD8(+), CD200(+) and CD11b/c(+) lymphocytes in the spleen. Rats that self-administered methamphetamine had a lower frequency of CD4(+) T cells, but more of these cells produced IFN-γ. Methamphetamine did not alter the frequency of TNF-α-producing CD4(+) T cells. Methamphetamine using rats had a higher frequency of CD8(+) T cells, but fewer of them produced TNF-α. CD11b/c and CD200 expression were unchanged. Serum cytokine levels of IFN-γ, TNF-α and IL-6 in methamphetamine rats were unchanged. Methamphetamine lifetime dose inversely correlated with serum TNF-α levels. Our data suggest that methamphetamine abuse may exacerbate HIV disease progression by activating CD4 T cells, making them more susceptible to HIV infection, and contributing to their premature demise. Methamphetamine may also increase susceptibility to HIV infection, explaining why men who have sex with men (MSM) and frequently use methamphetamine are at the highest risk of HIV infection. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. A model-based understanding of solid-oxide electrolysis cells (SOECs) for syngas production by H2O/CO2 co-electrolysis

    Science.gov (United States)

    Menon, Vikram; Fu, Qingxi; Janardhanan, Vinod M.; Deutschmann, Olaf

    2015-01-01

    High temperature co-electrolysis of H2O and CO2 offers a promising route for syngas (H2, CO) production via efficient use of heat and electricity. The performance of a SOEC during co-electrolysis is investigated by focusing on the interactions between transport processes and electrochemical parameters. Electrochemistry at the three-phase boundary is modeled by a modified Butler-Volmer approach that considers H2O electrolysis and CO2 electrolysis, individually, as electrochemically active charge transfer pathways. The model is independent of the geometrical structure. A 42-step elementary heterogeneous reaction mechanism for the thermo-catalytic chemistry in the fuel electrode, the dusty gas model (DGM) to account for multi-component diffusion through porous media, and a plug flow model for flow through the channels are used in the model. Two sets of experimental data are reproduced by the simulations, in order to deduce parameters of the electrochemical model. The influence of micro-structural properties, inlet cathode gas velocity, and temperature are discussed. Reaction flow analysis is performed, at OCV, to study methane production characteristics and kinetics during co-electrolysis. Simulations are carried out for configurations ranging from simple one-dimensional electrochemical button cells to quasi-two-dimensional co-flow planar cells, to demonstrate the effectiveness of the computational tool for performance and design optimization.

  2. Production of antibodies against glycolipids from the Mycobacterium tuberculosis cell wall in aerosol murine models of tuberculosis.

    Science.gov (United States)

    Cardona, P J; Julián, E; Vallès, X; Gordillo, S; Muñoz, M; Luquin, M; Ausina, V

    2002-06-01

    Evolution of antibodies against glycolipids from the Mycobacterium tuberculosis cell wall has been studied for the first time in experimental murine models of tuberculosis induced by aerosol, in which infection, reinfection, reactivation, prophylaxis and treatment with antibiotics have been assayed. Results show a significant humoral response against these antigens, where diacyltrehaloses (DAT) and sulpholipid I (SL-I) elicited higher antibody levels than protein antigens like antigen 85 protein complex (Ag85), culture filtrate proteins (CFP) and purified protein derivative (PPD). Only immunoglobulin M (IgM) antibodies have been detected against DAT and SL-I. Their evolution has a positive correlation with bacillary concentration in tissues.

  3. Tensor Product of Polygonal Cell Complexes

    OpenAIRE

    Chien, Yu-Yen

    2017-01-01

    We introduce the tensor product of polygonal cell complexes, which interacts nicely with the tensor product of link graphs of complexes. We also develop the unique factorization property of polygonal cell complexes with respect to the tensor product, and study the symmetries of tensor products of polygonal cell complexes.

  4. Low-cost production of solar-cell panels

    Science.gov (United States)

    Bickler, D. B.; Gallagher, B. D.; Sanchez, L. E.

    1980-01-01

    Large-scale production model combines most modern manufacturing techniques to produce silicon-solar-cell panels of low costs by 1982. Model proposes facility capable of operating around the clock with annual production capacity of 20 W of solar cell panels.

  5. Delivery of Bone Marrow-Derived Mesenchymal Stem Cells Improves Tear Production in a Mouse Model of Sjögren’s Syndrome

    Directory of Open Access Journals (Sweden)

    Hema S. Aluri

    2017-01-01

    Full Text Available The purpose of the present study was to test the potential of mouse bone marrow-derived mesenchymal stem cells (BD-MSCs in improving tear production in a mouse model of Sjögren’s syndrome dry eye and to investigate the underlying mechanisms involved. NOD mice (n=20 were randomized to receive i.p. injection of sterile phosphate buffered saline (PBS, control or murine BD-MSCs (1 × 106 cells. Tears production was measured at baseline and once a week after treatment using phenol red impregnated threads. Cathepsin S activity in the tears was measured at the end of treatment. After 4 weeks, animals were sacrificed and the lacrimal glands were excised and processed for histopathology, immunohistochemistry, and RNA analysis. Following BD-MSC injection, tears production increased over time when compared to both baseline and PBS injected mice. Although the number of lymphocytic foci in the lacrimal glands of treated animals did not change, the size of the foci decreased by 40.5% when compared to control animals. The mRNA level of the water channel aquaporin 5 was significantly increased following delivery of BD-MSCs. We conclude that treatment with BD-MSCs increases tear production in the NOD mouse model of Sjögren’s syndrome. This is likely due to decreased inflammation and increased expression of aquaporin 5.

  6. Modeling Novo Nordisk Production Systems

    DEFF Research Database (Denmark)

    Miller, Thomas Dedenroth

    1997-01-01

    This report describes attributes of models and systems, and how models can be used for description of production systems. There are special attention on the 'Theory of Domains'.......This report describes attributes of models and systems, and how models can be used for description of production systems. There are special attention on the 'Theory of Domains'....

  7. Two-Step Production of Phenylpyruvic Acid from L-Phenylalanine by Growing and Resting Cells of Engineered Escherichia coli: Process Optimization and Kinetics Modeling.

    Directory of Open Access Journals (Sweden)

    Ying Hou

    Full Text Available Phenylpyruvic acid (PPA is widely used in the pharmaceutical, food, and chemical industries. Here, a two-step bioconversion process, involving growing and resting cells, was established to produce PPA from l-phenylalanine using the engineered Escherichia coli constructed previously. First, the biotransformation conditions for growing cells were optimized (l-phenylalanine concentration 20.0 g·L-1, temperature 35°C and a two-stage temperature control strategy (keep 20°C for 12 h and increase the temperature to 35°C until the end of biotransformation was performed. The biotransformation conditions for resting cells were then optimized in 3-L bioreactor and the optimized conditions were as follows: agitation speed 500 rpm, aeration rate 1.5 vvm, and l-phenylalanine concentration 30 g·L-1. The total maximal production (mass conversion rate reached 29.8 ± 2.1 g·L-1 (99.3% and 75.1 ± 2.5 g·L-1 (93.9% in the flask and 3-L bioreactor, respectively. Finally, a kinetic model was established, and it was revealed that the substrate and product inhibition were the main limiting factors for resting cell biotransformation.

  8. Two-Step Production of Phenylpyruvic Acid from L-Phenylalanine by Growing and Resting Cells of Engineered Escherichia coli: Process Optimization and Kinetics Modeling.

    Science.gov (United States)

    Hou, Ying; Hossain, Gazi Sakir; Li, Jianghua; Shin, Hyun-Dong; Liu, Long; Du, Guocheng; Chen, Jian

    2016-01-01

    Phenylpyruvic acid (PPA) is widely used in the pharmaceutical, food, and chemical industries. Here, a two-step bioconversion process, involving growing and resting cells, was established to produce PPA from l-phenylalanine using the engineered Escherichia coli constructed previously. First, the biotransformation conditions for growing cells were optimized (l-phenylalanine concentration 20.0 g·L-1, temperature 35°C) and a two-stage temperature control strategy (keep 20°C for 12 h and increase the temperature to 35°C until the end of biotransformation) was performed. The biotransformation conditions for resting cells were then optimized in 3-L bioreactor and the optimized conditions were as follows: agitation speed 500 rpm, aeration rate 1.5 vvm, and l-phenylalanine concentration 30 g·L-1. The total maximal production (mass conversion rate) reached 29.8 ± 2.1 g·L-1 (99.3%) and 75.1 ± 2.5 g·L-1 (93.9%) in the flask and 3-L bioreactor, respectively. Finally, a kinetic model was established, and it was revealed that the substrate and product inhibition were the main limiting factors for resting cell biotransformation.

  9. Two-Step Production of Phenylpyruvic Acid from L-Phenylalanine by Growing and Resting Cells of Engineered Escherichia coli: Process Optimization and Kinetics Modeling

    Science.gov (United States)

    Hou, Ying; Hossain, Gazi Sakir; Li, Jianghua; Shin, Hyun-dong; Liu, Long; Du, Guocheng; Chen, Jian

    2016-01-01

    Phenylpyruvic acid (PPA) is widely used in the pharmaceutical, food, and chemical industries. Here, a two-step bioconversion process, involving growing and resting cells, was established to produce PPA from l-phenylalanine using the engineered Escherichia coli constructed previously. First, the biotransformation conditions for growing cells were optimized (l-phenylalanine concentration 20.0 g·L−1, temperature 35°C) and a two-stage temperature control strategy (keep 20°C for 12 h and increase the temperature to 35°C until the end of biotransformation) was performed. The biotransformation conditions for resting cells were then optimized in 3-L bioreactor and the optimized conditions were as follows: agitation speed 500 rpm, aeration rate 1.5 vvm, and l-phenylalanine concentration 30 g·L−1. The total maximal production (mass conversion rate) reached 29.8 ± 2.1 g·L−1 (99.3%) and 75.1 ± 2.5 g·L−1 (93.9%) in the flask and 3-L bioreactor, respectively. Finally, a kinetic model was established, and it was revealed that the substrate and product inhibition were the main limiting factors for resting cell biotransformation. PMID:27851793

  10. MOLTEN CARBONATE FUEL CELL PRODUCT DESIGN IMPROVEMENT

    Energy Technology Data Exchange (ETDEWEB)

    H.C. Maru; M. Farooque

    2003-03-01

    The program efforts are focused on technology and system optimization for cost reduction, commercial design development, and prototype system field trials. The program is designed to advance the carbonate fuel cell technology from full-size field test to the commercial design. FuelCell Energy, Inc. (FCE) is in the later stage of the multiyear program for development and verification of carbonate fuel cell based power plants supported by DOE/NETL with additional funding from DOD/DARPA and the FuelCell Energy team. FCE has scaled up the technology to full-size and developed DFC{reg_sign} stack and balance-of-plant (BOP) equipment technology to meet product requirements, and acquired high rate manufacturing capabilities to reduce cost. FCE has designed submegawatt (DFC300A) and megawatt (DFC1500 and DFC3000) class fuel cell products for commercialization of its DFC{reg_sign} technology. A significant progress was made during the reporting period. The reforming unit design was optimized using a three-dimensional stack simulation model. Thermal and flow uniformities of the oxidant-In flow in the stack module were improved using computational fluid dynamics based flow simulation model. The manufacturing capacity was increased. The submegawatt stack module overall cost was reduced by {approx}30% on a per kW basis. An integrated deoxidizer-prereformer design was tested successfully at submegawatt scale using fuels simulating digester gas, coal bed methane gas and peak shave (natural) gas.

  11. Protein hydrolysate from canned sardine and brewing by-products improves TNF-α-induced inflammation in an intestinal-endothelial co-culture cell model.

    Science.gov (United States)

    Vieira, Elsa F; Van Camp, John; Ferreira, Isabel M P L V O; Grootaert, Charlotte

    2017-07-17

    The anti-inflammatory activity of sardine protein hydrolysates (SPH) obtained by hydrolysis with proteases from brewing yeast surplus was ascertained. For this purpose, a digested and desalted SPH fraction with molecular weight lower than 10 kDa was investigated using an endothelial cell line (EA.hy926) as such and in a co-culture model with an intestinal cell line (Caco-2). Effects of SPH <10 kDa on nitric oxide (NO) production, reactive oxygen species (ROS) inhibition and secretion of monocyte chemoattractant protein 1 (MCP-1), vascular endothelial growth factor (VEGF), chemokine IL-8 (IL-8) and intercellular adhesion molecule-1 (ICAM-1) were evaluated in TNF-α-treated and untreated cells. Upon TNF-α treatment, levels of NO, MCP-1, VEGF, IL-8, ICAM-1 and endothelial ROS were significantly increased in both mono- and co-culture models. Treatment with SPH <10 kDa (2.0 mg peptides/mL) significantly decreased all the inflammation markers when compared to TNF-α-treated control. This protective effect was more pronounced in the co-culture model, suggesting that SPH <10 kDa Caco-2 cells metabolites produced in the course of intestinal absorption may provide a more relevant protective effect against endothelial dysfunction. Additionally, indirect cross-talk between two cell types was established, suggesting that SPH <10 kDa may also bind to receptors on the Caco-2 cells, thereby triggering a pathway to secrete the pro-inflammatory compounds. Overall, these in vitro screening results, in which intestinal digestion, absorption and endothelial bioactivity are simulated, show the potential of SPH to be used as a functional food with anti-inflammatory properties.

  12. PRODUCT STRUCTURE DIGITAL MODEL

    Directory of Open Access Journals (Sweden)

    V.M. Sineglazov

    2005-02-01

    Full Text Available  Research results of representation of product structure made by means of CADDS5 computer-aided design (CAD system, Product Data Management Optegra (PDM system and Product Life Cycle Management Wind-chill system (PLM, are examined in this work. Analysis of structure component development and its storage in various systems is carried out. Algorithms of structure transformation required for correct representation of the structure are considered. Management analysis of electronic mockup presentation of the product structure is carried out for Windchill system.

  13. Production of hyaline-like cartilage by bone marrow mesenchymal stem cells in a self-assembly model.

    Science.gov (United States)

    Elder, Steven H; Cooley, Avery J; Borazjani, Ali; Sowell, Brittany L; To, Harrison; Tran, Scott C

    2009-10-01

    A scaffoldless or self-assembly approach to cartilage tissue engineering has been used to produce hyaline cartilage from bone marrow-derived mesenchymal stem cells (bMSCs), but the mechanical properties of such engineered cartilage and the effects the transforming growth factor (TGF) isoform have not been fully explored. This study employs a cell culture insert model to produce tissue-engineered cartilage using bMSCs. Neonatal pig bMSCs were isolated by plastic adherence and expanded in monolayer before being seeded into porous transwell inserts and cultured for 4 or 8 weeks in defined chondrogenic media containing either TGF-beta1 or TGF-beta3. Following biomechanical evaluation in confined compression, colorimetric dimethyl methylene blue and Sircol dye-binding assays were used to analyze glycosaminoglycan (GAG) and collagen contents, respectively. Histological sections were stained with toluidine blue for proteoglycans and with picrosirius red to reveal collagen orientation, and immunostained for detection of collagen types I and II. Neocartilage increased in thickness, collagen, and GAG content between 4 and 8 weeks. Proteoglycan concentration increased with depth from the top surface. The tissue contained much more collagen type II than type I, and there was a consistent pattern of collagen alignment. TGF-beta1-treated and TGF-beta3-treated constructs were similar at 4 weeks, but 8-week TGF-beta1 constructs had a higher aggregate modulus and GAG content compared to TGF-beta3. These results demonstrate that bMSCs can generate functional hyaline-like cartilage through a self-assembling process.

  14. Influence of matrix nature on the functional efficacy of biomedical cell product for the regeneration of damaged liver (experimental model of acute liver failure

    Directory of Open Access Journals (Sweden)

    S. V. Gautier

    2017-01-01

    Full Text Available Aim. A comparative analysis of the functional efficacy of biomedical cell products (BMCP for the regeneration of damaged liver based on biopolymer scaffolded porous and hydrogel matrices was performed on the experimental model of acute liver failure. Materials and methods. Matrices allowed for clinical use were employed for BMCP in the form of a sponge made from biopolymer nanostructured composite material (BNCM based on a highly purified bacterial copolymers of poly (β-hydroxybutyrate-co-β-oxyvalerate and polyethylene glycol and a hydrogel matrix from biopolymer microheterogeneous collagen-containing hydrogel (BMCH. Cellular component of BMCP was represented by liver cells and multipotent mesenchymal bone marrow stem cells. The functional efficacy of BMCP for the regeneration of damaged liver was evaluated on the experimental model of acute liver failure in Wistar rats (n = 40 via biochemical, morphological, and immunohistochemical methods. Results. When BMCP was implanted to regenerate the damaged liver on the basis of the scaffolded BNCM or hydrogel BMCH matrices, the lethality in rats with acute liver failure was absent; while in control it was 66.6%. Restoration of the activity of cytolytic enzyme levels and protein-synthetic liver function began on day 9 after modeling acute liver failure, in contrast to the control group, where recovery occurred only by days 18–21. Both matrices maintained the viability and functional activity of liver cells up to 90 days with the formation of blood vessels in BMCP. The obtained data confirm that scaffolded BNCM matrix and hydrogel BMCH matrix retain for a long time (up to 90 days the vital activity of the adherent cells in the BMCP composition, which allows using them to correct acute liver failure. At the same time, hydrogel matrix due to the presence of bioactive components contributes to the creation of the best conditions for adhesion and cell activity which accelerate the regeneration processes

  15. European oil product supply modelling

    International Nuclear Information System (INIS)

    Saint-Antonin, V.

    1998-01-01

    Over the last few years, trends in European oil product consumption (in terms of level as structure and quality) has important implications of the refining industry. In this context, the purpose of this thesis consists in building a mathematical programming model applied to the European refineries in order to determine oil product supply prices, European refining industry investments and oil product exchanges of the European Union. The first part presents the reason for our choice for a long-term aggregate multi-refineries linear programming model, based on European refineries characteristics and the objectives of our model. Its dual properties are studied in detail and we focus particularly on the European exchange modelling. In the second part, an analysis of the European refining trends leads us to identify parameters and variables of the model that are essential to the aggregate representation of the European oil product supply. The third part is devoted to the use of this model, regarding two scenarios of increasingly stringent specifications for gasoline and diesel oil. Our interest for these products is due to their important share of the European oil product consumption and the not insignificant responsibility of the transport sector for atmospheric pollution. Finally, in order to have the use of an overall picture of the European refining industry, we build a regression model summarizing, though a few equations, the main relations between the major endogenous and exogenous variables o the LP model. Based on pseudo-data, this kind of model provides a simple and robust representation of the oil product supply. But a more specialized analysis of the refining industry operations, turning on a technical assessment of processing units, is reliant on the use of an optimization model such as the model we have built. (author)

  16. Geometrical model of multiple production

    International Nuclear Information System (INIS)

    Chikovani, Z.E.; Jenkovszky, L.L.; Kvaratshelia, T.M.; Struminskij, B.V.

    1988-01-01

    The relation between geometrical and KNO-scaling and their violation is studied in a geometrical model of multiple production of hadrons. Predictions concerning the behaviour of correlation coefficients at future accelerators are given

  17. MOLTEN CARBONATE FUEL CELL PRODUCT DESIGN IMPROVEMENT

    Energy Technology Data Exchange (ETDEWEB)

    H.C. Maru; M. Farooque

    2005-03-01

    The program was designed to advance the carbonate fuel cell technology from full-size proof-of-concept field test to the commercial design. DOE has been funding Direct FuelCell{reg_sign} (DFC{reg_sign}) development at FuelCell Energy, Inc. (FCE, formerly Energy Research Corporation) from an early state of development for stationary power plant applications. The current program efforts were focused on technology and system development, and cost reduction, leading to commercial design development and prototype system field trials. FCE, in Danbury, CT, is a world-recognized leader for the development and commercialization of high efficiency fuel cells that can generate clean electricity at power stations, or at distributed locations near the customers such as hospitals, schools, universities, hotels and other commercial and industrial applications. FCE has designed three different fuel cell power plant models (DFC300A, DFC1500 and DFC3000). FCE's power plants are based on its patented DFC{reg_sign} technology, where a hydrocarbon fuel is directly fed to the fuel cell and hydrogen is generated internally. These power plants offer significant advantages compared to the existing power generation technologies--higher fuel efficiency, significantly lower emissions, quieter operation, flexible siting and permitting requirements, scalability and potentially lower operating costs. Also, the exhaust heat by-product can be used for cogeneration applications such as high-pressure steam, district heating and air conditioning. Several sub-MW power plants based on the DFC design are currently operating in Europe, Japan and the US. Several one-megawatt power plant design was verified by operation on natural gas at FCE. This plant is currently installed at a customer site in King County, WA under another US government program and is currently in operation. Because hydrogen is generated directly within the fuel cell module from readily available fuels such as natural gas and

  18. Photovoltaic cell and production thereof

    Science.gov (United States)

    Narayanan, Srinivasamohan [Gaithersburg, MD; Kumar, Bikash [Bangalore, IN

    2008-07-22

    An efficient photovoltaic cell, and its process of manufacture, is disclosed wherein the back surface p-n junction is removed from a doped substrate having an oppositely doped emitter layer. A front surface and edges and optionally the back surface periphery are masked and a back surface etch is performed. The mask is not removed and acts as an anti-reflective coating, a passivating agent, or both. The photovoltaic cell retains an untextured back surface whether or not the front is textured and the dopant layer on the back surface is removed to enhance the cell efficiency. Optionally, a back surface field is formed.

  19. Glucose transport machinery reconstituted in cell models.

    Science.gov (United States)

    Hansen, Jesper S; Elbing, Karin; Thompson, James R; Malmstadt, Noah; Lindkvist-Petersson, Karin

    2015-02-11

    Here we demonstrate the production of a functioning cell model by formation of giant vesicles reconstituted with the GLUT1 glucose transporter and a glucose oxidase and hydrogen peroxidase linked fluorescent reporter internally. Hence, a simplified artificial cell is formed that is able to take up glucose and process it.

  20. Product models for the Construction industry

    DEFF Research Database (Denmark)

    Sørensen, Lars Schiøtt

    1996-01-01

    Different types of product models for the building sector was elaborated and grouped. Some discussion on the different models was given. The "definition" of Product models was given.......Different types of product models for the building sector was elaborated and grouped. Some discussion on the different models was given. The "definition" of Product models was given....

  1. Effect of failures and repairs on multiple cell production lines

    Energy Technology Data Exchange (ETDEWEB)

    Legato, P.; Bobbio, A.; Roberti, L.

    1989-01-01

    This paper examines a production line composed of multiple stages, or cells, which are passed in sequential order to arrive to the final product. Two possible coordination disciplines are considered, namely: the classical tandem arrangement of sequential working centers with input buffer and the kanban scheme, considered the Japanese shop floor realization of the Just-In-Time (JIT) manifacturing approach. The production line is modelled and analysed by means of Stochastic Petri Nets (SPN). Finally an analysis is made of the possibility that the working cells can incur failure/repair cycles perturbing the production flow of the line and thus reduce performance indices.

  2. the production of mouse embryonic stem cells

    Indian Academy of Sciences (India)

    MADU

    What history tells us VII. Twenty-five years ago: the production of mouse embryonic stem cells ... cells into the cavity of the blastocyst, it will be possible to test the effect of .... to the use of efficient immunosuppressive drugs like cyclosporin – was ...

  3. Bovine mammary stem cells: Cell biology meets production agriculture

    Science.gov (United States)

    Mammary stem cells (MaSC) provide for net growth, renewal and turnover of mammary epithelial cells, and are therefore potential targets for strategies to increase production efficiency. Appropriate regulation of MaSC can potentially benefit milk yield, persistency, dry period management and tissue ...

  4. Tetherin restricts productive HIV-1 cell-to-cell transmission.

    Directory of Open Access Journals (Sweden)

    Nicoletta Casartelli

    2010-06-01

    Full Text Available The IFN-inducible antiviral protein tetherin (or BST-2/CD317/HM1.24 impairs release of mature HIV-1 particles from infected cells. HIV-1 Vpu antagonizes the effect of tetherin. The fate of virions trapped at the cell surface remains poorly understood. Here, we asked whether tetherin impairs HIV cell-to-cell transmission, a major means of viral spread. Tetherin-positive or -negative cells, infected with wild-type or DeltaVpu HIV, were used as donor cells and cocultivated with target lymphocytes. We show that tetherin inhibits productive cell-to-cell transmission of DeltaVpu to targets and impairs that of WT HIV. Tetherin accumulates with Gag at the contact zone between infected and target cells, but does not prevent the formation of virological synapses. In the presence of tetherin, viruses are then mostly transferred to targets as abnormally large patches. These viral aggregates do not efficiently promote infection after transfer, because they accumulate at the surface of target cells and are impaired in their fusion capacities. Tetherin, by imprinting virions in donor cells, is the first example of a surface restriction factor limiting viral cell-to-cell spread.

  5. Strategies for fuel cell product development. Developing fuel cell products in the technology supply chain

    International Nuclear Information System (INIS)

    Hellman, H.L.

    2004-01-01

    Due to the high cost of research and development and the broad spectrum of knowledge and competences required to develop fuel cell products, many product-developing firms outsource fuel cell technology, either partly or completely. This article addresses the inter-firm process of fuel cell product development from an Industrial Design Engineering perspective. The fuel cell product development can currently be characterised by a high degree of economic and technical uncertainty. Regarding the technology uncertainty: product-developing firms are more often then not unfamiliar with fuel cell technology technology. Yet there is a high interface complexity between the technology supplied and the product in which it is to be incorporated. In this paper the information exchange in three current fuel cell product development projects is analysed to determine the information required by a product designer to develop a fuel cell product. Technology transfer literature suggests that transfer effectiveness is greatest when the type of technology (technology uncertainty) and the type of relationship between the technology supplier and the recipient are carefully matched. In this line of thinking this paper proposes that the information required by a designer, determined by the design strategy and product/system volume, should be met by an appropriate level of communication interactivity with a technology specialist. (author)

  6. A model for optimizing the production of pharmaceutical products

    Directory of Open Access Journals (Sweden)

    Nevena Gospodinova

    2017-05-01

    Full Text Available The problem associated with the optimal production planning is especially relevant in modern industrial enterprises. The most commonly used optimality criteria in this context are: maximizing the total profit; minimizing the cost per unit of production; maximizing the capacity utilization; minimizing the total production costs. This article aims to explore the possibility for optimizing the production of pharmaceutical products through the construction of a mathematical model that can be viewed in two ways – as a single-product model and a multi-product model. As an optimality criterion it is set the minimization of the cost per unit of production for a given planning period. The author proposes an analytical method for solving the nonlinear optimization problem. An optimal production plan of Tylosin tartrate is found using the single-product model.

  7. Product Family Modelling for Manufacturing Planning

    DEFF Research Database (Denmark)

    Jørgensen, Kaj Asbjørn; Petersen, Thomas Ditlev; Nielsen, Kjeld

    2011-01-01

    To enable product configuration of a product family, it is important to develop a model of the selected product family. From such a model, an often performed practice is to make a product configurator from which customers can specify individual products from the family. To get further utilisation...

  8. Synthetic yeast based cell factories for vanillin-glucoside production

    DEFF Research Database (Denmark)

    Strucko, Tomas

    and controlled expression/overexpression of genes of interest. De novo biosynthetic pathway for vanillin-β-glucoside production was employed as a model system for several case studies in this project. In order to construct yeast cell factories fulfilling current demands of industrial biotechnology, methods......The yeast Saccharomyces cerevisiae is well a characterized microorganism and widely used as eukaryotic model organism as well as a key cell factory for bioproduction of various products. The latter comprise a large variety of scientifically and industrially relevant products such as low-value bulk...... chemicals and biofuels, food additives, high-value chemicals and recombinant proteins. Despite the recent achievements in the fields of systems biology and metabolic engineering together with availability of broad genetic engineering toolbox, the full potential of S. cerevisiae as a cell factory is not yet...

  9. Production economic models of fisheries

    DEFF Research Database (Denmark)

    Andersen, Jesper Levring

    The overall purpose of this PhD thesis is to investigate different aspects of fishermen’s behaviour using production economic models at the individual and industry levels. Three parts make up this thesis. The first part provides an overview of the thesis. The second part consists of four papers......, including all relevant factors in specific analyses is impossible, and it is therefore important to be aware of the most essential ones. As demonstrated in the literature review of Paper 1, a large number of factors may significantly influence fishermen’s short run behaviour, i.e. choice of gear type...

  10. Continued SOFC cell and stack technology and improved production methods

    Energy Technology Data Exchange (ETDEWEB)

    Wandel, M.; Brodersen, K.; Phair, J. (and others)

    2009-05-15

    Within this project significant results are obtained on a number of very diverse areas ranging from development of cell production, metallic creep in interconnect to assembling and test of stacks with foot print larger than 500 cm2. Out of 38 milestones 28 have been fulfilled and 10 have been partly fulfilled. This project has focused on three main areas: 1) The continued cell development and optimization of manufacturing processes aiming at production of large foot-print cells, improving cell performance and development environmentally more benign production methods. 2) Stack technology - especially stacks with large foot print and improving the stack design with respect to flow geometry and gas leakages. 3) Development of stack components with emphasis on sealing (for 2G as well as 3G), interconnect (coat, architecture and creep) and test development. Production of cells with a foot print larger than 500 cm2 is very difficult due to the brittleness of the cells and great effort has been put into this topic. Eight cells were successfully produced making it possible to assemble and test a real stack thereby giving valuable results on the prospects of stacks with large foot print. However, the yield rate is very low and a significant development to increase this yield lies ahead. Several lessons were learned on the stack level regarding 'large foot print' stacks. Modelling studies showed that the width of the cell primarily is limited by production and handling of the cell whereas the length (in the flow direction) is limited by e.g. pressure drop and necessary manifolding. The optimal cell size in the flow direction was calculated to be between approx20 cm and < 30 cm. From an economical point of view the production yield is crucial and stacks with large foot print cell area are only feasible if the cell production yield is significantly enhanced. Co-casting has been pursued as a production technique due to the possibilities in large scale production

  11. Modeling fuel cell stack systems

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J H [Los Alamos National Lab., Los Alamos, NM (United States); Lalk, T R [Dept. of Mech. Eng., Texas A and M Univ., College Station, TX (United States)

    1998-06-15

    A technique for modeling fuel cell stacks is presented along with the results from an investigation designed to test the validity of the technique. The technique was specifically designed so that models developed using it can be used to determine the fundamental thermal-physical behavior of a fuel cell stack for any operating and design configuration. Such models would be useful tools for investigating fuel cell power system parameters. The modeling technique can be applied to any type of fuel cell stack for which performance data is available for a laboratory scale single cell. Use of the technique is demonstrated by generating sample results for a model of a Proton Exchange Membrane Fuel Cell (PEMFC) stack consisting of 125 cells each with an active area of 150 cm{sup 2}. A PEMFC stack was also used in the verification investigation. This stack consisted of four cells, each with an active area of 50 cm{sup 2}. Results from the verification investigation indicate that models developed using the technique are capable of accurately predicting fuel cell stack performance. (orig.)

  12. Work productivity in rhinitis using cell phones

    DEFF Research Database (Denmark)

    Bousquet, J.; Bewick, Bridgette M; Arnavielhe, S

    2017-01-01

    Allergic rhinitis often impairs social life and performance. The aim of this cross-sectional study was to use cell phone data to assess the impact on work productivity of uncontrolled rhinitis assessed by visual analogue scale (VAS). A mobile phone app (Allergy Diary, Google Play Store and Apple ...

  13. Production and Reliability Oriented SOFC Cell and Stack Design

    DEFF Research Database (Denmark)

    Hauth, Martin; Lawlor, Vincent; Cartellieri, Peter

    2017-01-01

    The paper presents an innovative development methodology for a production and reliability oriented SOFC cell and stack design aiming at improving the stacks robustness, manufacturability, efficiency and cost. Multi-physics models allowed a probabilistic approach to consider statistical variations...... in production, material and operating parameters for the optimization phase. A methodology for 3D description of spatial distribution of material properties based on a random field models was developed and validated by experiments. Homogenized material models on multiple levels of the SOFC stack were...... and output parameters and to perform a sensitivity analysis were developed and implemented. The capabilities of the methodology is illustrated on two practical cases....

  14. Fuel Cell Electric Vehicle Composite Data Products | Hydrogen and Fuel

    Science.gov (United States)

    Cells | NREL Vehicle Composite Data Products Fuel Cell Electric Vehicle Composite Data Products The following composite data products (CDPs) focus on current fuel cell electric vehicle evaluations Cell Operation Hour Groups CDP FCEV 39, 2/19/16 Comparison of Fuel Cell Stack Operation Hours and Miles

  15. A Production Model for Deteriorating Inventory Items with Production Disruptions

    OpenAIRE

    Yong He; Ju He

    2010-01-01

    Disruption management has recently become an active area of research. In this study, an extension is made to consider the fact that some products may deteriorate during storage. A production-inventory model for deteriorating items with production disruptions is developed. Then the optimal production and inventory plans are provided, so that the manufacturer can reduce the loss caused by disruptions. Finally, a numerical example is used to illustrate the model.

  16. Pigment Production Analysis in Human Melanoma Cells.

    Science.gov (United States)

    Hopkin, Amelia Soto; Paterson, Elyse K; Ruiz, Rolando; Ganesan, Anand K

    2016-05-25

    The human epidermal melanocyte is a highly specialized pigmented cell that serves to protect the epidermis from ultraviolet (UV) damage through the production of melanin, or melanogenesis. Misregulation in melanogenesis leading to either hyper- or hypo-pigmentation is found in human diseases such as malasma and vitiligo. Current therapies for these diseases are largely unsuccessful and the need for new therapies is necessary. In order to identify genes and or compounds that can alter melanogenesis, methods are required that can detect changes in pigment production as well as expression of key melanogenesis transcription factors and enzymes. Here we describe methods to detect changes in melanogenesis in a human melanoma cell line, MNT-1, by (1) analyzing pigment production by measuring the absorbance of melanin present by spectrophotometry, (2) analyzing transcript expression of potent regulators of melanogenesis by qunatitative reverse-transcription (RT)PCR and (3) analyzing protein expression of potent regulators of melanogenesis by Western blot (WB).

  17. Direct fuel cell product design improvement

    Energy Technology Data Exchange (ETDEWEB)

    Maru, H.C.; Farooque, M. [Energy Research Corp., Danbury, CT (United States)

    1996-12-31

    Significant milestones have been attained towards the technology development field testing and commercialization of direct fuel cell power plant since the 1994 Fuel Cell Seminar. Under a 5-year cooperative agreement with the Department of Energy signed in December 1994, Energy Research Corporation (ERC) has been developing the design for a MW-scale direct fuel cell power plant with input from previous technology efforts and the Santa Clara Demonstration Project. The effort encompasses product definition in consultation with the Fuel Cell Commercialization Group, potential customers, as well as extensive system design and packaging. Manufacturing process improvements, test facility construction, cell component scale up, performance and endurance improvements, stack engineering, and critical balance-of-plant development are also addressed. Major emphasis of this product design improvement project is on increased efficiency, compactness and cost reduction to establish a competitive place in the market. A 2.85 MW power plant with an efficiency of 58% and a footprint of 420 m{sup 2} has been designed. Component and subsystem testing is being conducted at various levels. Planning and preparation for verification of a full size prototype unit are in progress. This paper presents the results obtained since the last fuel cell seminar.

  18. Extending product modeling methods for integrated product development

    DEFF Research Database (Denmark)

    Bonev, Martin; Wörösch, Michael; Hauksdóttir, Dagný

    2013-01-01

    Despite great efforts within the modeling domain, the majority of methods often address the uncommon design situation of an original product development. However, studies illustrate that development tasks are predominantly related to redesigning, improving, and extending already existing products...... and PVM methods, in a presented Product Requirement Development model some of the individual drawbacks of each method could be overcome. Based on the UML standard, the model enables the representation of complex hierarchical relationships in a generic product model. At the same time it uses matrix....... Updated design requirements have then to be made explicit and mapped against the existing product architecture. In this paper, existing methods are adapted and extended through linking updated requirements to suitable product models. By combining several established modeling techniques, such as the DSM...

  19. Role of positive ions on the surface production of negative ions in a fusion plasma reactor type negative ion source--Insights from a three dimensional particle-in-cell Monte Carlo collisions model

    Science.gov (United States)

    Fubiani, G.; Boeuf, J. P.

    2013-11-01

    Results from a 3D self-consistent Particle-In-Cell Monte Carlo Collisions (PIC MCC) model of a high power fusion-type negative ion source are presented for the first time. The model is used to calculate the plasma characteristics of the ITER prototype BATMAN ion source developed in Garching. Special emphasis is put on the production of negative ions on the plasma grid surface. The question of the relative roles of the impact of neutral hydrogen atoms and positive ions on the cesiated grid surface has attracted much attention recently and the 3D PIC MCC model is used to address this question. The results show that the production of negative ions by positive ion impact on the plasma grid is small with respect to the production by atomic hydrogen or deuterium bombardment (less than 10%).

  20. Role of positive ions on the surface production of negative ions in a fusion plasma reactor type negative ion source—Insights from a three dimensional particle-in-cell Monte Carlo collisions model

    International Nuclear Information System (INIS)

    Fubiani, G.; Boeuf, J. P.

    2013-01-01

    Results from a 3D self-consistent Particle-In-Cell Monte Carlo Collisions (PIC MCC) model of a high power fusion-type negative ion source are presented for the first time. The model is used to calculate the plasma characteristics of the ITER prototype BATMAN ion source developed in Garching. Special emphasis is put on the production of negative ions on the plasma grid surface. The question of the relative roles of the impact of neutral hydrogen atoms and positive ions on the cesiated grid surface has attracted much attention recently and the 3D PIC MCC model is used to address this question. The results show that the production of negative ions by positive ion impact on the plasma grid is small with respect to the production by atomic hydrogen or deuterium bombardment (less than 10%)

  1. Modelling of virtual production networks

    Directory of Open Access Journals (Sweden)

    2011-03-01

    Full Text Available Nowadays many companies, especially small and medium-sized enterprises (SMEs, specialize in a limited field of production. It requires forming virtual production networks of cooperating enterprises to manufacture better, faster and cheaper. Apart from that, some production orders cannot be realized, because there is not a company of sufficient production potential. In this case the virtual production networks of cooperating companies can realize these production orders. These networks have larger production capacity and many different resources. Therefore it can realize many more production orders together than each of them separately. Such organization allows for executing high quality product. The maintenance costs of production capacity and used resources are not so high. In this paper a methodology of rapid prototyping of virtual production networks is proposed. It allows to execute production orders on time considered existing logistic constraints.

  2. A procedure for Building Product Models

    DEFF Research Database (Denmark)

    Hvam, Lars

    1999-01-01

    , easily adaptable concepts and methods from data modeling (object oriented analysis) and domain modeling (product modeling). The concepts are general and can be used for modeling all types of specifications in the different phases in the product life cycle. The modeling techniques presented have been......The application of product modeling in manufacturing companies raises the important question of how to model product knowledge in a comprehensible and efficient way. An important challenge is to qualify engineers to model and specify IT-systems (product models) to support their specification...... activities. A basic assumption is that engineers have to take the responsability for building product models to be used in their domain. To do that they must be able to carry out the modeling task on their own without any need for support from computer science experts. This paper presents a set of simple...

  3. A Causal Model of Faculty Research Productivity.

    Science.gov (United States)

    Bean, John P.

    A causal model of faculty research productivity was developed through a survey of the literature. Models of organizational behavior, organizational effectiveness, and motivation were synthesized into a causal model of productivity. Two general types of variables were assumed to affect individual research productivity: institutional variables and…

  4. Stochastic models of cell motility

    DEFF Research Database (Denmark)

    Gradinaru, Cristian

    2012-01-01

    Cell motility and migration are central to the development and maintenance of multicellular organisms, and errors during this process can lead to major diseases. Consequently, the mechanisms and phenomenology of cell motility are currently under intense study. In recent years, a new...... interdisciplinary field focusing on the study of biological processes at the nanoscale level, with a range of technological applications in medicine and biological research, has emerged. The work presented in this thesis is at the interface of cell biology, image processing, and stochastic modeling. The stochastic...... models introduced here are based on persistent random motion, which I apply to real-life studies of cell motility on flat and nanostructured surfaces. These models aim to predict the time-dependent position of cell centroids in a stochastic manner, and conversely determine directly from experimental...

  5. Alignment of Product Models and Product State Models - Integration of the Product Lifecycle Phases

    DEFF Research Database (Denmark)

    Larsen, Michael Holm; Kirkby, Lars Phillip; Vesterager, Johan

    1999-01-01

    The purpose of this paper is to discuss the integration of the Product Model (PM) and the Product State Model (PCM). Focus is on information exchange from the PSM to the PM within the manufacturing of a single ship. The paper distinguishes between information and knowledge integration. The paper ...... provides some overall strategies for integrating PM and PSM. The context of this discussion is a development project at Odense Steel Shipyard....

  6. Plutonium production in a remote cell

    International Nuclear Information System (INIS)

    Maddux, E.P.; Purcell, J.A.

    1987-01-01

    Production of 239 Pu metal has traditionally been carried out in glovebox enclosures for protection of operating personnel and the environment. With the advent of more stringent federal regulations for protecting personnel, the environment, and security of special nuclear materials, it is proposed that plutonium be processed in a totally remote environment using automated work stations and robotic materials transfer and equipment maintenance. At the Savannah River Plant, the existing plutonium production facility is a batch-type glovebox operation built in the 1950s. A viable alternative to restoration of the existing glovebox operation is to provide a facility that uses remote cell operation

  7. HAMCIND, Cell Burnup with Fission Products Poisoning

    International Nuclear Information System (INIS)

    Abe, Alfredo Y.; Dos Santos, Adimir

    2002-01-01

    1 - Description of program or function: HAMCIND is a cell burnup code based in a coupling between HAMMER-TECHNION and CINDER. The fission product poisoning is taken into account in an explicit fashion. 2 - Method of solution: The nonlinear coupled set of equations for the neutron transport and nuclide transmutation equations and nuclide transmutation equations in a unit cell is solved by HAMCIND in a quasi-static approach. The spectral transport equation is solved by HAMMER-TECHNION at the beginning of each time-step while the nuclide transmutation equations are solved by CINDER for every time-step. The HAMMER-TECHNION spectral calculations are performed taking into account the fission product contribution to the macroscopic cross sections (fast and thermal), in the inelastic scattering matrix and even in the thermal scattering matrices. 3 - Restrictions on the complexity of the problem: Restrictions and/or limitations for HAMCIND depend upon the local operating system

  8. Viability of fuel cells for car production

    Energy Technology Data Exchange (ETDEWEB)

    Buchel, J.-P. [Renault, Trappes (France); Lisse, J.-P. [P.S.A., Trappes (France); Bernard, S. [Alten, Trappes (France)

    2000-07-01

    The two French car manufacturers PSA Peugeot Citroen and Renault both sell pure electric cars in an effort to reduce pollutants and carbon dioxide emissions. In addition, they have each studied fuel cell car prototypes in relation to the FEVER program for Renault and the HYDRO-GEN program for PSA. In 1999, the two manufacturers joined forces in a common program to evaluate the technical, economical and environmental viability of the fuel cell vehicle potential. The joint program has active contributions by Air Liquid, the French Atomic Energy Agency, De Nora Fuel Cells, Elf-Antar-France, Totalfina and Valeo. This paper highlighted many of the components of this program and the suitability of this new technology for industrial production at a cost competitive price. Certain automotive constraints have to be considered to propose vehicles which could provide good performance in varying temperature and operating conditions. Safety is also an important concern given that the vehicles are powered by hydrogen and a high voltage power source. Another challenges is the choice of the fuel and the economic cost of a new refueling infrastructure. Recycling was suggested as a means to recover expensive fuel cell system components such as precious catalysts, bipolar plates, membranes and other main specific parts of the fuel cell vehicle. This paper also discussed issues regarding the thermal management of the fuel cell power plant and air conditioning of the vehicles. figs.

  9. A procedure for building product models

    DEFF Research Database (Denmark)

    Hvam, Lars; Riis, Jesper; Malis, Martin

    2001-01-01

    This article presents a procedure for building product models to support the specification processes dealing with sales, design of product variants and production preparation. The procedure includes, as the first phase, an analysis and redesign of the business processes, which are to be supported...... with product models. The next phase includes an analysis of the product assortment, and the set up of a so-called product master. Finally the product model is designed and implemented using object oriented modelling. The procedure is developed in order to ensure that the product models constructed are fit...... for the business processes they support, and properly structured and documented, in order to facilitate that the systems can be maintained continually and further developed. The research has been carried out at the Centre for Industrialisation of Engineering, Department of Manufacturing Engineering, Technical...

  10. Physical models of cell motility

    CERN Document Server

    2016-01-01

    This book surveys the most recent advances in physics-inspired cell movement models. This synergetic, cross-disciplinary effort to increase the fidelity of computational algorithms will lead to a better understanding of the complex biomechanics of cell movement, and stimulate progress in research on related active matter systems, from suspensions of bacteria and synthetic swimmers to cell tissues and cytoskeleton.Cell motility and collective motion are among the most important themes in biology and statistical physics of out-of-equilibrium systems, and crucial for morphogenesis, wound healing, and immune response in eukaryotic organisms. It is also relevant for the development of effective treatment strategies for diseases such as cancer, and for the design of bioactive surfaces for cell sorting and manipulation. Substrate-based cell motility is, however, a very complex process as regulatory pathways and physical force generation mechanisms are intertwined. To understand the interplay between adhesion, force ...

  11. Model cell membranes

    DEFF Research Database (Denmark)

    Günther-Pomorski, Thomas; Nylander, Tommy; Cardenas Gomez, Marite

    2014-01-01

    The high complexity of biological membranes has motivated the development and application of a wide range of model membrane systems to study biochemical and biophysical aspects of membranes in situ under well defined conditions. The aim is to provide fundamental understanding of processes control...

  12. On production costs in vertical differentiation models

    OpenAIRE

    Dorothée Brécard

    2009-01-01

    In this paper, we analyse the effects of the introduction of a unit production cost beside a fixed cost of quality improvement in a duopoly model of vertical product differentiation. Thanks to an original methodology, we show that a low unit cost tends to reduce product differentiation and thus prices, whereas a high unit cost leads to widen product differentiation and to increase prices

  13. An Optimization Model for Product Placement on Product Listing Pages

    Directory of Open Access Journals (Sweden)

    Yan-Kwang Chen

    2014-01-01

    Full Text Available The design of product listing pages is a key component of Website design because it has significant influence on the sales volume on a Website. This study focuses on product placement in designing product listing pages. Product placement concerns how venders of online stores place their products over the product listing pages for maximization of profit. This problem is very similar to the offline shelf management problem. Since product information sources on a Web page are typically communicated through the text and image, visual stimuli such as color, shape, size, and spatial arrangement often have an effect on the visual attention of online shoppers and, in turn, influence their eventual purchase decisions. In view of the above, this study synthesizes the visual attention literature and theory of shelf-space allocation to develop a mathematical programming model with genetic algorithms for finding optimal solutions to the focused issue. The validity of the model is illustrated with example problems.

  14. Proactive Modeling of Market, Product and Production Architectures

    DEFF Research Database (Denmark)

    Mortensen, Niels Henrik; Hansen, Christian Lindschou; Hvam, Lars

    2011-01-01

    This paper presents an operational model that allows description of market, products and production architectures. The main feature of this model is the ability to describe both structural and functional aspect of architectures. The structural aspect is an answer to the question: What constitutes...... the architecture, e.g. standard designs, design units and interfaces? The functional aspect is an answer to the question: What is the behaviour or the architecture, what is it able to do, i.e. which products at which performance levels can be derived from the architecture? Among the most important benefits...... of this model is the explicit ability to describe what the architecture is prepared for, and what it is not prepared for - concerning development of future derivative products. The model has been applied in a large scale global product development project. Among the most important benefits is contribution to...

  15. Negligible penetration of incidental amounts of alpha-hydroxy acid from rinse-off personal care products in human skin using an in vitro static diffusion cell model.

    Science.gov (United States)

    Okuda, M; Donahue, D A; Kaufman, L E; Avalos, J; Simion, F A; Story, D C; Sakaguchi, H; Fautz, R; Fuchs, A

    2011-12-01

    Alpha-hydroxy acids (AHAs), primarily glycolic and lactic acids, are widely used in cosmetics to alleviate dyspigmentation, photodamage, and other aging skin conditions and as pH adjusters. Glycolic acid reportedly enhances skin damage after repeated ultraviolet light exposure, e.g., increased sunburn cell formation. This study assessed potential in vitro skin penetration of lactic acid and malic acid incorporated into rinse-off personal care products, compared with rinse-off and leave-on exposures to glycolic acid (10%, pH 3.5) in a reference lotion. Radiolabeled AHA-fortified shampoo, conditioner, and lotion were evenly applied as single doses to human epidermal membranes mounted in static diffusion cells (not occluded). Exposures were 1-3 min (rinse-off) or 24 h (leave-on). Epidermal penetration of malic acid and lactic acid from the rinse-off shampoo and conditioner, respectively, was negligible, with >99% removed by rinsing, a negligible portion remaining in the stratum corneum (≤0.15%), and even less penetrating into the viable epidermis (≤0.04%). Glycolic acid penetration from the leave-on reference lotion was 1.42 μg equiv./cm2/h, with total absorbable dose recovery (receptor fluid plus epidermis) of 2.51%, compared to 0.009%, 0.003%, and 0.04% for the rinse-off reference lotion, shampoo (malic acid), and conditioner (lactic acid) exposures, respectively. Dermal penetration of AHAs into human skin is pH-, concentration-, and time-dependent. Alpha-hydroxy acids in rinse-off shampoos and conditioners are almost entirely removed from the skin within minutes by rinsing (resulting in negligible epidermal penetration). This suggests that ultraviolet radiation-induced skin effects of AHA-containing rinse-off products are negligible. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. MASS CUSTOMIZATION and PRODUCT MODELS

    DEFF Research Database (Denmark)

    Svensson, Carsten; Malis, Martin

    2003-01-01

    to the product. Through the application of a mass customization strategy, companies have a unique opportunity to create increased customer satisfaction. In a customized production, knowledge and information have to be easily accessible since every product is a unique combination of information. If the dream...... of a customized alternative instead of a uniform mass-produced product shall become a reality, then the cross-organizational efficiency must be kept at a competitive level. This is the real challenge for mass customization. A radical restructuring of both the internal and the external knowledge management systems...

  17. Modeling dependencies in product families with COVAMOF

    NARCIS (Netherlands)

    Sinnema, Marco; Deelstra, Sybren; Nijhuis, Jos; Bosch, Jan; Riebisch, M; Tabeling, P; Zorn, W

    2006-01-01

    Many variability modeling approaches consider only formalized dependencies, i.e. in- or exclude relations between variants. However, in real industrial product families, dependencies are often much more complicated. In this paper, we discuss the product derivation problems associated with

  18. BOREAS TE-17 Production Efficiency Model Images

    Data.gov (United States)

    National Aeronautics and Space Administration — A BOREAS version of the Global Production Efficiency Model(www.inform.umd.edu/glopem) was developed by TE-17 to generate maps of gross and net primary production,...

  19. Modelling Product Families for Product Configuration Systems with Product Variant Master

    DEFF Research Database (Denmark)

    Mortensen, Niels Henrik; Hvam, Lars; Haug, Anders

    2010-01-01

    This article presents an evaluation of applying a suggested method for modelling product families for product configuration based on theory for modelling mechanical products,systems theory and object-oriented modelling. The modelling technique includes a so-called product variant master and CRC-cards...... the three views. Modelling of characteristics of the product variants in a product family Modelling of constraints between parts in the product family Visualisation of the entire product family on a poster e.g. 1x2 meters The product variant master and CRC-cards are means to bridge the gap between domain...... experts and IT-developers, thus making it possible for the domain experts (e.g. engineers from product development) to express their knowledge in a form that is understandable both for the domain experts and the IT-developers. The product variant master and CRC-cards have currently been tested and further...

  20. Production Methods for a Mesenchymal Stem Cell Therapeutic as a Medical Defense Countermeasure

    Science.gov (United States)

    2012-02-01

    mesenchymal stem cell (MSC) efficacy in a variety of injury models demonstrate the unique qualities of this reparative cell population to adapt to the...therapeutic product. Characterization of stem cell properties of culture-expanded MSCs is shown by in vitro differentiation to form mature cell types. The

  1. CRC-cards for Product Modelling

    DEFF Research Database (Denmark)

    Hvam, Lars; Riis, Jesper; Hansen, Benjamin Loer

    2003-01-01

    , transportation, service and decommissioning. A main challenge when building product models is to collect and document the product related data, information and knowledge in a structured way. CRC cards are index cards (or computerized versions of these) which are used to record proposed classes, the behavior......This paper describes the CRC (class, responsibility, collaboration) modelling process for building product models. A product model is normally represented in an IT system which contains data, information and knowledge on industrial products and their life cycle properties e.g. manufacturing...... of the classes, their responsibilities, and their relationship to other classes (collaboration). CRC modelling gives an effective, low-tech method for domain-experts, programmers and users to work closely together to identify, structure, understand and document a product model. CRC cards were originally...

  2. Engineered CHO cells for production of diverse, homogeneous glycoproteins

    DEFF Research Database (Denmark)

    Yang, Zhang; Wang, Shengjun; Halim, Adnan

    2015-01-01

    Production of glycoprotein therapeutics in Chinese hamster ovary (CHO) cells is limited by the cells' generic capacity for N-glycosylation, and production of glycoproteins with desirable homogeneous glycoforms remains a challenge. We conducted a comprehensive knockout screen of glycosyltransferas...

  3. Solid oxide fuel cells and hydrogen production

    International Nuclear Information System (INIS)

    Dogan, F.

    2009-01-01

    'Full text': A single-chamber solid oxide fuel cell (SC-SOFC), operating in a mixture of fuel and oxidant gases, provides several advantages over the conventional SOFC such as simplified cell structure (no sealing required). SC-SOFC allows using a variety of fuels without carbon deposition by selecting appropriate electrode materials and cell operating conditions. The operating conditions of single chamber SOFC was studied using hydrocarbon-air gas mixtures for a cell composed of NiO-YSZ / YSZ / LSCF-Ag. The cell performance and catalytic activity of the anode was measured at various gas flow rates. The results showed that the open-circuit voltage and the power density increased as the gas flow rate increased. Relatively high power densities up to 660 mW/cm 2 were obtained in a SC-SOFC using porous YSZ electrolytes instead of dense electrolytes required for operation of a double chamber SOFC. In addition to propane- or methane-air mixtures as a fuel source, the cells were also tested in a double chamber configuration using hydrogen-air mixtures by controlling the hydrogen/air ratio at the cathode and the anode. Simulation of single chamber conditions in double chamber configurations allows distinguishing and better understanding of the electrode reactions in the presence of mixed gases. Recent research efforts; the effect of hydrogen-air mixtures as a fuel source on the performance of anode and cathode materials in single-chamber and double-chamber SOFC configurations,will be presented. The presentation will address a review on hydrogen production by utilizing of reversible SOFC systems. (author)

  4. Description, Modelling and Design of Production Systems

    DEFF Research Database (Denmark)

    Jacobsen, Peter; Rudolph, Carsten

    1997-01-01

    Design of production systems are rarely an activity in which decision makers in most production companies have much experience. In future, this activity is to be more recurrent due to more and more frequent changes in the production task. Consequently, the decision makers are in need of better...... management tools and methods for description and modelling of production systems supporting the decisions. In this article a structural framework to describe and model production systems will be introduced, and it is shown how the production system of a minor Danish manufacturer of electromechanical...

  5. Production of soluble Neprilysin by endothelial cells

    International Nuclear Information System (INIS)

    Kuruppu, Sanjaya; Rajapakse, Niwanthi W.; Minond, Dmitriy; Smith, A. Ian

    2014-01-01

    Highlights: • A soluble full-length form of Neprilysin exists in media of endothelial cells. • Exosomal release is the key mechanism for the production of soluble Neprilysin. • Inhibition of ADAM-17 by specific inhibitors reduce Neprilysin release. • Exosome mediated release of Neprilysin is dependent on ADAM-17 activity. - Abstract: A non-membrane bound form of Neprilysin (NEP) with catalytic activity has the potential to cleave substrates throughout the circulation, thus leading to systemic effects of NEP. We used the endothelial cell line Ea.hy926 to identify the possible role of exosomes and A Disintegrin and Metalloprotease 17 (ADAM-17) in the production of non-membrane bound NEP. Using a bradykinin based quenched fluorescent substrate (40 μM) assay, we determined the activity of recombinant human NEP (rhNEP; 12 ng), and NEP in the media of endothelial cells (10% v/v; after 24 h incubation with cells) to be 9.35 ± 0.70 and 6.54 ± 0.41 μmols of substrate cleaved over 3 h, respectively. The presence of NEP in the media was also confirmed by Western blotting. At present there are no commercially available inhibitors specific for ADAM-17. We therefore synthesised two inhibitors TPI2155-14 and TPI2155-17, specific for ADAM-17 with IC 50 values of 5.36 and 4.32 μM, respectively. Treatment of cells with TPI2155-14 (15 μM) and TPI2155-17 (4.3 μM) resulted in a significant decrease in NEP activity in media (62.37 ± 1.43 and 38.30 ± 4.70, respectively as a % of control; P < 0.0001), implicating a possible role for ADAM-17 in NEP release. However, centrifuging media (100,000g for 1 h at 4 °C) removed all NEP activity from the supernatant indicating the likely role of exosomes in the release of NEP. Our data therefore indicated for the first time that NEP is released from endothelial cells via exosomes, and that this process is dependent on ADAM-17

  6. A grand model for chemical product design

    DEFF Research Database (Denmark)

    Fung, Ka Y.; Ng, Ka M.; Zhang, Lei

    2016-01-01

    , a pricing model, an economic model as well as factors such as company strategy, government policies and regulations. This article introduces the model and highlights selected aspects of the model with two case studies. One is a die attach adhesive that illustrates how pricing affects profitability, and how...... product composition changes with market conditions. Another is a hand lotion that illustrates how product quality affects the profit.(C) 2016 Elsevier Ltd. All rights reserved....

  7. PAPER PRINTED PHOTOVOLTAIC CELLS: EMERGING METHOD OF PV CELL PRODUCTION

    OpenAIRE

    Nikhil S. Mane*, Avinash M. Patil2, Vishal P. Patil3

    2017-01-01

    An Solar energy is a renewable method for the energy production. The use of solar energy is increasing day by day and share of solar energy is increasing in the power sector of India. But as per pollution increases with energy consumption the need of solar energy will goes on increase in recent future as solar energy is a best option in both thermal and photovoltaic energy conversion processes. Photovoltaic cells are compact and has no movable parts which provides them effectiveness and easy ...

  8. Classification hierarchies for product data modelling

    NARCIS (Netherlands)

    Pels, H.J.

    2006-01-01

    Abstraction is an essential element in data modelling that appears mainly in one of the following forms: generalisation, classification or aggregation. In the design of complex products classification hierarchies can be found product families that are viewed as classes of product types, while

  9. Marketing Modeling for New Products

    NARCIS (Netherlands)

    C. Hernández-Mireles (Carlos)

    2010-01-01

    textabstractThis thesis addresses the analysis of new or very recent marketing data and the introduction of new marketing models. We present a collection of models that are useful to analyze (1) the optimal launch time of new and dominant technologies, (2) the triggers, speed and timing of new

  10. Design, Modeling, and Development of Microbial Cell Factories

    KAUST Repository

    Kodzius, Rimantas

    2014-03-26

    Using Metagenomic analysis, computational modeling, single cell and genome editing technologies, we will express desired microbial genes and their networks in suitable hosts for mass production of energy, food, and fine chemicals.

  11. Design, Modeling, and Development of Microbial Cell Factories

    KAUST Repository

    Kodzius, Rimantas; Behzad, H.; Archer, John A.C.; Bajic, Vladimir B.; Gojobori, Takashi

    2014-01-01

    Using Metagenomic analysis, computational modeling, single cell and genome editing technologies, we will express desired microbial genes and their networks in suitable hosts for mass production of energy, food, and fine chemicals.

  12. Ensemble modeling for aromatic production in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Matthew L Rizk

    2009-09-01

    Full Text Available Ensemble Modeling (EM is a recently developed method for metabolic modeling, particularly for utilizing the effect of enzyme tuning data on the production of a specific compound to refine the model. This approach is used here to investigate the production of aromatic products in Escherichia coli. Instead of using dynamic metabolite data to fit a model, the EM approach uses phenotypic data (effects of enzyme overexpression or knockouts on the steady state production rate to screen possible models. These data are routinely generated during strain design. An ensemble of models is constructed that all reach the same steady state and are based on the same mechanistic framework at the elementary reaction level. The behavior of the models spans the kinetics allowable by thermodynamics. Then by using existing data from the literature for the overexpression of genes coding for transketolase (Tkt, transaldolase (Tal, and phosphoenolpyruvate synthase (Pps to screen the ensemble, we arrive at a set of models that properly describes the known enzyme overexpression phenotypes. This subset of models becomes more predictive as additional data are used to refine the models. The final ensemble of models demonstrates the characteristic of the cell that Tkt is the first rate controlling step, and correctly predicts that only after Tkt is overexpressed does an increase in Pps increase the production rate of aromatics. This work demonstrates that EM is able to capture the result of enzyme overexpression on aromatic producing bacteria by successfully utilizing routinely generated enzyme tuning data to guide model learning.

  13. Plutonium production in a remote automated cell

    International Nuclear Information System (INIS)

    Maddux, E.P.; Purcell, J.A.

    1987-01-01

    Production of 239 Pu metal has traditionally been carried out in glove box enclosures to protect operating personnel and the outside environment from the hazards of radiation. With the advent of more stringent federal regulations for protecting personnel, the environment, and security of special nuclear materials, it is proposed that plutonium be processed in a totally remote environment using automated work stations and robotic materials transfer and equipment maintenance. Investigators envision a facility where operations are carried out in two remotely operated cells. One cell will contain aqueous processing operations while the second will contain powder operations. Various processing steps will be carried out on modular frames of a standard configuration. The processing equipment on each frame will be completely automated and operated via computer. Nonaqueous materials will be transferred between frames by robots using closed-circuit television and computer control. Robots will be able to perform limited in-place maintenance of equipment on each frame for high-maintenance replaceable components. When major repair is required, the processing frame will be decoupled by the robot and moved to a decontamination and maintenance area by a conventional overhead bridge crane. The new design concept will provide for long-term goals, which include exposure reduction, near-real time accountability, safeguards, and waste reduction

  14. Kinetic study and modeling of biosurfactant production using Bacillus sp.

    Directory of Open Access Journals (Sweden)

    Hesty Heryani

    2017-05-01

    Conclusions: For further development and industrial applications, the modified Gompertz equation is proposed to predict the cell mass and biosurfactant production as a goodness of fit was obtained with this model. The modified Gompertz equation was also extended to enable the excellent prediction of the surface tension.

  15. Linear programming model can explain respiration of fermentation products

    Science.gov (United States)

    Möller, Philip; Liu, Xiaochen; Schuster, Stefan

    2018-01-01

    Many differentiated cells rely primarily on mitochondrial oxidative phosphorylation for generating energy in the form of ATP needed for cellular metabolism. In contrast most tumor cells instead rely on aerobic glycolysis leading to lactate to about the same extent as on respiration. Warburg found that cancer cells to support oxidative phosphorylation, tend to ferment glucose or other energy source into lactate even in the presence of sufficient oxygen, which is an inefficient way to generate ATP. This effect also occurs in striated muscle cells, activated lymphocytes and microglia, endothelial cells and several mammalian cell types, a phenomenon termed the “Warburg effect”. The effect is paradoxical at first glance because the ATP production rate of aerobic glycolysis is much slower than that of respiration and the energy demands are better to be met by pure oxidative phosphorylation. We tackle this question by building a minimal model including three combined reactions. The new aspect in extension to earlier models is that we take into account the possible uptake and oxidation of the fermentation products. We examine the case where the cell can allocate protein on several enzymes in a varying distribution and model this by a linear programming problem in which the objective is to maximize the ATP production rate under different combinations of constraints on enzymes. Depending on the cost of reactions and limitation of the substrates, this leads to pure respiration, pure fermentation, and a mixture of respiration and fermentation. The model predicts that fermentation products are only oxidized when glucose is scarce or its uptake is severely limited. PMID:29415045

  16. Linear programming model can explain respiration of fermentation products.

    Science.gov (United States)

    Möller, Philip; Liu, Xiaochen; Schuster, Stefan; Boley, Daniel

    2018-01-01

    Many differentiated cells rely primarily on mitochondrial oxidative phosphorylation for generating energy in the form of ATP needed for cellular metabolism. In contrast most tumor cells instead rely on aerobic glycolysis leading to lactate to about the same extent as on respiration. Warburg found that cancer cells to support oxidative phosphorylation, tend to ferment glucose or other energy source into lactate even in the presence of sufficient oxygen, which is an inefficient way to generate ATP. This effect also occurs in striated muscle cells, activated lymphocytes and microglia, endothelial cells and several mammalian cell types, a phenomenon termed the "Warburg effect". The effect is paradoxical at first glance because the ATP production rate of aerobic glycolysis is much slower than that of respiration and the energy demands are better to be met by pure oxidative phosphorylation. We tackle this question by building a minimal model including three combined reactions. The new aspect in extension to earlier models is that we take into account the possible uptake and oxidation of the fermentation products. We examine the case where the cell can allocate protein on several enzymes in a varying distribution and model this by a linear programming problem in which the objective is to maximize the ATP production rate under different combinations of constraints on enzymes. Depending on the cost of reactions and limitation of the substrates, this leads to pure respiration, pure fermentation, and a mixture of respiration and fermentation. The model predicts that fermentation products are only oxidized when glucose is scarce or its uptake is severely limited.

  17. A physiological production model for cacao : results of model simulations

    NARCIS (Netherlands)

    Zuidema, P.A.; Leffelaar, P.A.

    2002-01-01

    CASE2 is a physiological model for cocoa (Theobroma cacao L.) growth and yield. This report introduces the CAcao Simulation Engine for water-limited production in a non-technical way and presents simulation results obtained with the model.

  18. Effects of blood products on inflammatory response in endothelial cells in vitro.

    Directory of Open Access Journals (Sweden)

    Martin Urner

    Full Text Available BACKGROUND: Transfusing blood products may induce inflammatory reactions within the vascular compartment potentially leading to a systemic inflammatory response. Experiments were designed to assess the inflammatory potential of different blood products in an endothelial cell-based in vitro model and to compare baseline levels of potentially activating substances in transfusion products. METHODS: The inflammatory response from pre-activated (endotoxin-stimulated and non-activated endothelial cells as well as neutrophil endothelial transmigration in response to packed red blood cells (PRBC, platelet concentrates (PC and fresh frozen plasma (FFP was determined. Baseline inflammatory mediator and lipid concentrations in blood products were evaluated. RESULTS: Following incubation with all blood products, an increased inflammatory mediator release from endothelial cells was observed. Platelet concentrates, and to a lesser extent also FFP, caused the most pronounced response, which was accentuated in already pre-stimulated endothelial cells. Inflammatory response of endothelial cells as well as blood product-induced migration of neutrophils through the endothelium was in good agreement with the lipid content of the according blood product. CONCLUSION: Within the group of different blood transfusion products both PC and FFP have a high inflammatory potential with regard to activation of endothelial cells. Inflammation upon blood product exposure is strongly accentuated when endothelial cells are pre-injured. High lipid contents in the respective blood products goes along with an accentuated inflammatory reaction from endothelial cells.

  19. Modelling Configuration Knowledge in Heterogeneous Product Families

    DEFF Research Database (Denmark)

    Queva, Matthieu Stéphane Benoit; Männistö, Tomi; Ricci, Laurent

    2011-01-01

    Product configuration systems play an important role in the development of Mass Customisation. The configuration of complex product families may nowadays involve multiple design disciplines, e.g. hardware, software and services. In this paper, we present a conceptual approach for modelling...... the variability in such heterogeneous product families. Our approach is based on a framework that aims to cater for the different stakeholders involved in the modelling and management of the product family. The modelling approach is centred around the concepts of views, types and constraints and is illustrated...... by a motivation example. Furthermore, as a proof of concept, a prototype has been implemented for configuring a non-trivial heterogeneous product family....

  20. Hybrid simulation models of production networks

    CERN Document Server

    Kouikoglou, Vassilis S

    2001-01-01

    This book is concerned with a most important area of industrial production, that of analysis and optimization of production lines and networks using discrete-event models and simulation. The book introduces a novel approach that combines analytic models and discrete-event simulation. Unlike conventional piece-by-piece simulation, this method observes a reduced number of events between which the evolution of the system is tracked analytically. Using this hybrid approach, several models are developed for the analysis of production lines and networks. The hybrid approach combines speed and accuracy for exceptional analysis of most practical situations. A number of optimization problems, involving buffer design, workforce planning, and production control, are solved through the use of hybrid models.

  1. REVIEW OF AQUACULTURAL PRODUCTION SYSTEM MODELS

    African Journals Online (AJOL)

    user

    models of aquacultural production systems with the aim of adopting a suitable one for ... of predicting the environmental condition, so as to determine point of diminishing returns and optimize yield in an ..... sale of fish are also tracked.

  2. Framework for product knowledge and product related knowledge which supports product modelling for mass customization

    DEFF Research Database (Denmark)

    Riis, Jesper; Hansen, Benjamin Loer; Hvam, Lars

    2003-01-01

    on experience from product modelling projects in several companies. Among them for example companies manufacturing electronic switchboards, spray dryer systems and air conditioning equipment. The framework is divided into three views: the product knowledge view, the life phase system view and the transformation...... and personalization. The framework for product knowledge and product related knowledge is based on the following theories: axiomatic design, technical systems, theory of domains, theory of structuring, theory of properties and the framework for the content of product and product related models. The framework is built......The article presents a framework for product knowledge and product related knowledge which can be used to support the product modelling process which is needed for developing IT systems. These IT systems are important tools for many companies when they aim at achieving mass customization...

  3. Statistical Model Checking for Product Lines

    DEFF Research Database (Denmark)

    ter Beek, Maurice H.; Legay, Axel; Lluch Lafuente, Alberto

    2016-01-01

    average cost of products (in terms of the attributes of the products’ features) and the probability of features to be (un)installed at runtime. The product lines must be modelled in QFLan, which extends the probabilistic feature-oriented language PFLan with novel quantitative constraints among features...

  4. A model for persistency of egg production

    NARCIS (Netherlands)

    Grossman, M.; Gossman, T.N.; Koops, W.J.

    2000-01-01

    The objectives of our study were to propose a new definition for persistency of egg production and to develop a mathematical model to describe the egg production curve, one that includes a new measure for persistency, based on the proposed definition, for use as a selection criterion to improve

  5. Solar Cell Production in Nigeria: Prospects, Options and Problems

    International Nuclear Information System (INIS)

    Fasasi, A. Y.; Siyanbola, W.O.; Ibitoye, F. I.; Pelemo, D. A.

    2002-01-01

    The prospects and problems facing solar cell production in Nigeria are discussed. The paper reviews many proven solar cell materials in terms of their current efficiencies and production costs. Silicon solar cell production appears to be the best technology option for Nigeria because of the abundant quartz sand and waste products from our phosphate fertiliser company that can be employed as starting materials to produce solar grade silicon. Factors affecting solar cell efficiency, choice of solar cell as well as financial and material problems limiting the progress on silicon solar cell production are also discussed. Finally, the paper recommends the simultaneous production of solar grade silicon and coordinated development of the balance of system components as first steps towards actualizing this objective

  6. Modeling oil production based on symbolic regression

    International Nuclear Information System (INIS)

    Yang, Guangfei; Li, Xianneng; Wang, Jianliang; Lian, Lian; Ma, Tieju

    2015-01-01

    Numerous models have been proposed to forecast the future trends of oil production and almost all of them are based on some predefined assumptions with various uncertainties. In this study, we propose a novel data-driven approach that uses symbolic regression to model oil production. We validate our approach on both synthetic and real data, and the results prove that symbolic regression could effectively identify the true models beneath the oil production data and also make reliable predictions. Symbolic regression indicates that world oil production will peak in 2021, which broadly agrees with other techniques used by researchers. Our results also show that the rate of decline after the peak is almost half the rate of increase before the peak, and it takes nearly 12 years to drop 4% from the peak. These predictions are more optimistic than those in several other reports, and the smoother decline will provide the world, especially the developing countries, with more time to orchestrate mitigation plans. -- Highlights: •A data-driven approach has been shown to be effective at modeling the oil production. •The Hubbert model could be discovered automatically from data. •The peak of world oil production is predicted to appear in 2021. •The decline rate after peak is half of the increase rate before peak. •Oil production projected to decline 4% post-peak

  7. Modeling Fission Product Sorption in Graphite Structures

    International Nuclear Information System (INIS)

    Szlufarska, Izabela; Morgan, Dane; Allen, Todd

    2013-01-01

    The goal of this project is to determine changes in adsorption and desorption of fission products to/from nuclear-grade graphite in response to a changing chemical environment. First, the project team will employ principle calculations and thermodynamic analysis to predict stability of fission products on graphite in the presence of structural defects commonly observed in very high-temperature reactor (VHTR) graphites. Desorption rates will be determined as a function of partial pressure of oxygen and iodine, relative humidity, and temperature. They will then carry out experimental characterization to determine the statistical distribution of structural features. This structural information will yield distributions of binding sites to be used as an input for a sorption model. Sorption isotherms calculated under this project will contribute to understanding of the physical bases of the source terms that are used in higher-level codes that model fission product transport and retention in graphite. The project will include the following tasks: Perform structural characterization of the VHTR graphite to determine crystallographic phases, defect structures and their distribution, volume fraction of coke, and amount of sp2 versus sp3 bonding. This information will be used as guidance for ab initio modeling and as input for sorptivity models; Perform ab initio calculations of binding energies to determine stability of fission products on the different sorption sites present in nuclear graphite microstructures. The project will use density functional theory (DFT) methods to calculate binding energies in vacuum and in oxidizing environments. The team will also calculate stability of iodine complexes with fission products on graphite sorption sites; Model graphite sorption isotherms to quantify concentration of fission products in graphite. The binding energies will be combined with a Langmuir isotherm statistical model to predict the sorbed concentration of fission products

  8. Construction of a biodynamic model for Cry protein production studies.

    Science.gov (United States)

    Navarro-Mtz, Ana Karin; Pérez-Guevara, Fermín

    2014-12-01

    Mathematical models have been used from growth kinetic simulation to gen regulatory networks prediction for B. thuringiensis culture. However, this culture is a time dependent dynamic process where cells physiology suffers several changes depending on the changes in the cell environment. Therefore, through its culture, B. thuringiensis presents three phases related with the predominance of three major metabolic pathways: vegetative growth (Embded-Meyerhof-Parnas pathway), transition (γ-aminobutiric cycle) and sporulation (tricarboxylic acid cycle). There is not available a mathematical model that relates the different stages of cultivation with the metabolic pathway active on each one of them. Therefore, in the present study, and based on published data, a biodynamic model was generated to describe the dynamic of the three different phases based on their major metabolic pathways. The biodynamic model is used to study the interrelation between the different culture phases and their relationship with the Cry protein production. The model consists of three interconnected modules where each module represents one culture phase and its principal metabolic pathway. For model validation four new fermentations were done showing that the model constructed describes reasonably well the dynamic of the three phases. The main results of this model imply that poly-β-hydroxybutyrate is crucial for endospore and Cry protein production. According to the yields of dipicolinic acid and Cry from poly-β-hydroxybutyrate, calculated with the model, the endospore and Cry protein production are not just simultaneous and parallel processes they are also competitive processes.

  9. A mathematical model to forecast uranium production

    International Nuclear Information System (INIS)

    Camisani-Calzolari, F.A.G.M.

    1987-01-01

    The uranium production forecasting program described in this paper projects production from reasonably assured, estimated additional and speculative resources in the cost categories of less than $130/kg U. Originally designed to handle South African production, it has been expanded and redimensioned using available published information to forecast production for countries of the Western World. The program forecasts production from up to 400 plants over a period of fifty years and has built-in production models derived from documented historical data of the more important uranium provinces. It is particularly suitable to assess production capabilities on a national and global scale where variations in outputs for the individual plants tend to even out. The program is aimed at putting the uranium potential of any one country into a realistic perspective, and it could thus be useful for planning purposes and marketing strategies

  10. Engineered mammalian cells for production of recombinant proteins

    DEFF Research Database (Denmark)

    2017-01-01

    The present invention relates to mammalian cells modified to provide for improved expression of a recombinant protein of interest. In particular, the invention relates to CHO cells and other host cells in which the expression of one or more endogenous secreted proteins has been disrupted, as well...... as to the preparation, identification and use of such cells in the production of recombinant proteins....

  11. Continuum-level modelling of cellular adhesion and matrix production in aggregates.

    Science.gov (United States)

    Geris, Liesbet; Ashbourn, Joanna M A; Clarke, Tim

    2011-05-01

    Key regulators in tissue-engineering processes such as cell culture and cellular organisation are the cell-cell and cell-matrix interactions. As mathematical models are increasingly applied to investigate biological phenomena in the biomedical field, it is important, for some applications, that these models incorporate an adequate description of cell adhesion. This study describes the development of a continuum model that represents a cell-in-gel culture system used in bone-tissue engineering, namely that of a cell aggregate embedded in a hydrogel. Cell adhesion is modelled through the use of non-local (integral) terms in the partial differential equations. The simulation results demonstrate that the effects of cell-cell and cell-matrix adhesion are particularly important for the survival and growth of the cell population and the production of extracellular matrix by the cells, concurring with experimental observations in the literature.

  12. Recombinant Protein Production and Insect Cell Culture and Process

    Science.gov (United States)

    Spaulding, Glenn F. (Inventor); Goodwin, Thomas J. (Inventor); OConnor, Kim C. (Inventor); Francis, Karen M. (Inventor); Andrews, Angela D. (Inventor); Prewett, Tracey L. (Inventor)

    1997-01-01

    A process has been developed for recombinant production of selected polypeptides using transformed insect cells cultured in a horizontally rotating culture vessel modulated to create low shear conditions. A metabolically transformed insect cell line is produced using the culture procedure regardless of genetic transformation. The recombinant polypeptide can be produced by an alternative process using virtually infected or stably transformed insect cells containing a gene encoding the described polypeptide. The insect cells can also be a host for viral production.

  13. Microbial electrolysis cells as innovative technology for hydrogen production

    International Nuclear Information System (INIS)

    Chorbadzhiyska, Elitsa; Hristov, Georgi; Mitov, Mario; Hubenova, Yolina

    2011-01-01

    Hydrogen production is becoming increasingly important in view of using hydrogen in fuel cells. However, most of the production of hydrogen so far comes from the combustion of fossil fuels and water electrolysis. Microbial Electrolysis Cell (MEC), also known as Bioelectrochemically Assisted Microbial Reactor, is an ecologically clean, renewable and innovative technology for hydrogen production. Microbial electrolysis cells produce hydrogen mainly from waste biomass assisted by various bacteria strains. The principle of MECs and their constructional elements are reviewed and discussed. Keywords: microbial Electrolysis Cells, hydrogen production, waste biomass purification

  14. Simple electrolytic cell for production of elemental fluorine

    International Nuclear Information System (INIS)

    Dides F, M.; Padilla S, U.

    1990-01-01

    It was constructed and tested a simple electrolytic cell for the production of elemental fluorine. The fluorine production is essential in the obtainment of uranium hexafluoride, a compound for the nuclear fuel cycle. (A.C.A.S.)

  15. Effects of irradiation on cytokine production in glioma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Yamanaka, Ryuya; Tanaka, Ryuichi; Yoshida, Seiichi [Niigata Univ. (Japan). Brain Research Inst.

    1993-11-01

    The effects of irradiation on cytokine production in glioma cell lines, NP1, NP2 and NP3, were studied. Culture supernatants were collected after 6, 24, 48 or 72 hours and the concentrations of interleukin (IL)-6 and IL-8 measured by enzyme-linked immunosorbent assay. Spontaneous and IL-1[beta]-stimulated productions were analyzed. Some cells were given a single dose of Lineac irradiation (10 or 20 Gy). Production of IL-6 (with or without IL-1[beta] stimulation) increased gradually to a maximum after 72 hours, more in the 20 Gy-irradiated cells than 10 Gy cells (p<0.01). Production of IL-8 increased gradually to a maximum after 48 or 72 hours. Spontaneous production of IL-8 increased more in 20 Gy-irradiated cells than 10 Gy cells after 6 and 24 hours (p<0.01), but increased more in 10 Gy cells than 20 Gy cells after 48 and 72 hours (p<0.01). The production of IL-8 stimulated by IL-1[beta] increased more in 10 Gy cells than 20 Gy cells 24 hours later (p<0.01). IL-6 and IL-8 production differed in the response to irradiation. Our data suggest that bidirectional communication between the immune system and glioma cells changes after radiotherapy. (author).

  16. Topography of ganglion cell production in the cat's retina

    International Nuclear Information System (INIS)

    Walsh, C.; Polley, E.H.

    1985-01-01

    The ganglion cells of the cat's retina form several classes distinguishable in terms of soma size, axon diameter, dendritic morphology, physiological properties, and central connections. Labeling with [ 3 H]thymidine shows that the ganglion cells which survive in the adult are produced as several temporally shifted, overlapping waves: medium-sized cells are produced before large cells, whereas the smallest ganglion cells are produced throughout the period of ganglion cell generation. Large cells and medium-sized cells show the same distinctive pattern of production, forming rough spirals around the area centralis. The oldest cells tend to lie superior and nasal to the area centralis, whereas cells in the inferior nasal retina and inferior temporal retina are, in general, progressively younger. Within each retinal quadrant, cells nearer the area centralis tend to be older than cells in the periphery, but there is substantial overlap. The retinal raphe divides the superior temporal quadrant into two zones with different patterns of cell addition. Superior temporal retina near the vertical meridian adds cells only slightly later than superior nasal retina, whereas superior temporal retina near the horizontal meridian adds cells very late, contemporaneously with inferior temporal retina. The broader wave of production of smaller ganglion cells seems to follow this same spiral pattern at its beginning and end. The presence of the area centralis as a nodal point about which ganglion cell production in the retinal quadrants pivots suggests that the area centralis is already an important retinal landmark even at the earliest stages of retinal development

  17. Methods for Stem Cell Production and Therapy

    Science.gov (United States)

    Valluri, Jagan V. (Inventor); Claudio, Pier Paolo (Inventor)

    2015-01-01

    The present invention relates to methods for rapidly expanding a stem cell population with or without culture supplements in simulated microgravity conditions. The present invention relates to methods for rapidly increasing the life span of stem cell populations without culture supplements in simulated microgravity conditions. The present invention also relates to methods for increasing the sensitivity of cancer stem cells to chemotherapeutic agents by culturing the cancer stem cells under microgravity conditions and in the presence of omega-3 fatty acids. The methods of the present invention can also be used to proliferate cancer cells by culturing them in the presence of omega-3 fatty acids. The present invention also relates to methods for testing the sensitivity of cancer cells and cancer stem cells to chemotherapeutic agents by culturing the cancer cells and cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce tissue for use in transplantation by culturing stem cells or cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce cellular factors and growth factors by culturing stem cells or cancer stem cells under microgravity conditions. The methods of the present invention can also be used to produce cellular factors and growth factors to promote differentiation of cancer stem cells under microgravity conditions.

  18. A deterministic aggregate production planning model considering quality of products

    International Nuclear Information System (INIS)

    Madadi, Najmeh; Wong, Kuan Yew

    2013-01-01

    Aggregate Production Planning (APP) is a medium-term planning which is concerned with the lowest-cost method of production planning to meet customers' requirements and to satisfy fluctuating demand over a planning time horizon. APP problem has been studied widely since it was introduced and formulated in 1950s. However, in several conducted studies in the APP area, most of the researchers have concentrated on some common objectives such as minimization of cost, fluctuation in the number of workers, and inventory level. Specifically, maintaining quality at the desirable level as an objective while minimizing cost has not been considered in previous studies. In this study, an attempt has been made to develop a multi-objective mixed integer linear programming model that serves those companies aiming to incur the minimum level of operational cost while maintaining quality at an acceptable level. In order to obtain the solution to the multi-objective model, the Fuzzy Goal Programming approach and max-min operator of Bellman-Zadeh were applied to the model. At the final step, IBM ILOG CPLEX Optimization Studio software was used to obtain the experimental results based on the data collected from an automotive parts manufacturing company. The results show that incorporating quality in the model imposes some costs, however a trade-off should be done between the cost resulting from producing products with higher quality and the cost that the firm may incur due to customer dissatisfaction and sale losses.

  19. Revised Reynolds Stress and Triple Product Models

    Science.gov (United States)

    Olsen, Michael E.; Lillard, Randolph P.

    2017-01-01

    Revised versions of Lag methodology Reynolds-stress and triple product models are applied to accepted test cases to assess the improvement, or lack thereof, in the prediction capability of the models. The Bachalo-Johnson bump flow is shown as an example for this abstract submission.

  20. In silico characterization of cell-cell interactions using a cellular automata model of cell culture.

    Science.gov (United States)

    Kihara, Takanori; Kashitani, Kosuke; Miyake, Jun

    2017-07-14

    Cell proliferation is a key characteristic of eukaryotic cells. During cell proliferation, cells interact with each other. In this study, we developed a cellular automata model to estimate cell-cell interactions using experimentally obtained images of cultured cells. We used four types of cells; HeLa cells, human osteosarcoma (HOS) cells, rat mesenchymal stem cells (MSCs), and rat smooth muscle A7r5 cells. These cells were cultured and stained daily. The obtained cell images were binarized and clipped into squares containing about 10 4 cells. These cells showed characteristic cell proliferation patterns. The growth curves of these cells were generated from the cell proliferation images and we determined the doubling time of these cells from the growth curves. We developed a simple cellular automata system with an easily accessible graphical user interface. This system has five variable parameters, namely, initial cell number, doubling time, motility, cell-cell adhesion, and cell-cell contact inhibition (of proliferation). Within these parameters, we obtained initial cell numbers and doubling times experimentally. We set the motility at a constant value because the effect of the parameter for our simulation was restricted. Therefore, we simulated cell proliferation behavior with cell-cell adhesion and cell-cell contact inhibition as variables. By comparing growth curves and proliferation cell images, we succeeded in determining the cell-cell interaction properties of each cell. Simulated HeLa and HOS cells exhibited low cell-cell adhesion and weak cell-cell contact inhibition. Simulated MSCs exhibited high cell-cell adhesion and positive cell-cell contact inhibition. Simulated A7r5 cells exhibited low cell-cell adhesion and strong cell-cell contact inhibition. These simulated results correlated with the experimental growth curves and proliferation images. Our simulation approach is an easy method for evaluating the cell-cell interaction properties of cells.

  1. IL-12 immunotherapy of minimal residual disease in murine models of HPV16-associated tumours: induction of immune responses, cytokine production and kinetics of immune cell subsets

    Czech Academy of Sciences Publication Activity Database

    Indrová, Marie; Bieblová, Jana; Bubeník, Jan; Reiniš, Milan

    2008-01-01

    Roč. 32, č. 2 (2008), s. 499-507 ISSN 1019-6439 R&D Projects: GA ČR GA301/06/0774 EU Projects: European Commission(XE) 18933 - CLINIGENE Institutional research plan: CEZ:AV0Z50520514 Keywords : HPV 16 * MHC class I-positive and -deficient tumours * immature myeloid cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.234, year: 2008

  2. Organic production in a dynamic CGE model

    DEFF Research Database (Denmark)

    Jacobsen, Lars Bo

    2004-01-01

    for conventional production into land for organic production, a period of two years must pass before the land being transformed can be used for organic production. During that time, the land is counted as land of the organic industry, but it can only produce the conventional product. To handle this rule, we make......Concerns about the impact of modern agriculture on the environment have in recent years led to an interest in supporting the development of organic farming. In addition to environmental benefits, the aim is to encourage the provision of other “multifunctional” properties of organic farming...... such as rural amenities and rural development that are spillover benefit additional to the supply of food. In this paper we further develop an existing dynamic general equilibrium model of the Danish economy to specifically incorporate organic farming. In the model and input-output data each primary...

  3. Device and materials modeling in PEM fuel cells

    CERN Document Server

    Promislow, Keith

    2009-01-01

    Device and Materials Modeling in PEM Fuel Cells is a specialized text that compiles the mathematical details and results of both device and materials modeling in a single volume. Proton exchange membrane (PEM) fuel cells will likely have an impact on our way of life similar to the integrated circuit. The potential applications range from the micron scale to large scale industrial production. Successful integration of PEM fuel cells into the mass market will require new materials and a deeper understanding of the balance required to maintain various operational states. This book contains articles from scientists who contribute to fuel cell models from both the materials and device perspectives. Topics such as catalyst layer performance and operation, reactor dynamics, macroscopic transport, and analytical models are covered under device modeling. Materials modeling include subjects relating to the membrane and the catalyst such as proton conduction, atomistic structural modeling, quantum molecular dynamics, an...

  4. Review of existing landfill leachate production models

    International Nuclear Information System (INIS)

    Khan, T.A.

    2000-01-01

    The protection of water resources is a fundamental consideration in managing landfill operations. Landfill sites should be designed and operated so as to control leachate production and hence minimize the risk of surface and ground water pollution. A further important development is the use of computer models to estimate the production of leachate from landfill sites. It is revealed from the literature that a number of landfill leachate management model lave been development in recent years. These models allow different engineering schemes to be evaluated and are essential tools for design and operation managements of modern landfills. This paper describes a review of such models mainly focused on their theory, practicability, data requirements, suitability to real situation and usefulness. An evaluation of these models identifies. (author)

  5. Product with service, technology with business model

    DEFF Research Database (Denmark)

    Sakao, Tomohiko; McAloone, Tim C.

    2011-01-01

    Looking back over the last decade, the importance of an expanded understanding of engineering design has been shared within the engineering design community. Presented concepts and methods to support such expansion include Functional Product Development, Service Engineering, and Product/Service-S...... promising concept beyond PSS design; via an integrated development of technology and business model. This can be of particular interest for further research, especially due to its high freedom for designers....

  6. STEP - Product Model Data Sharing and Exchange

    DEFF Research Database (Denmark)

    Kroszynski, Uri

    1998-01-01

    During the last fifteen years, a very large effort to standardize the product models employed in product design, manufacturing and other life-cycle phases has been undertaken. This effort has the acronym STEP, and resulted in the International Standard ISO-10303 "Industrial Automation Systems...... - Product Data Representation and Exchange", featuring at present some 30 released parts, and growing continuously. Many of the parts are Application Protocols (AP). This article presents an overview of STEP, based upon years of involvement in three ESPRIT projects, which contributed to the development...

  7. A neurocomputational model of automatic sequence production.

    Science.gov (United States)

    Helie, Sebastien; Roeder, Jessica L; Vucovich, Lauren; Rünger, Dennis; Ashby, F Gregory

    2015-07-01

    Most behaviors unfold in time and include a sequence of submovements or cognitive activities. In addition, most behaviors are automatic and repeated daily throughout life. Yet, relatively little is known about the neurobiology of automatic sequence production. Past research suggests a gradual transfer from the associative striatum to the sensorimotor striatum, but a number of more recent studies challenge this role of the BG in automatic sequence production. In this article, we propose a new neurocomputational model of automatic sequence production in which the main role of the BG is to train cortical-cortical connections within the premotor areas that are responsible for automatic sequence production. The new model is used to simulate four different data sets from human and nonhuman animals, including (1) behavioral data (e.g., RTs), (2) electrophysiology data (e.g., single-neuron recordings), (3) macrostructure data (e.g., TMS), and (4) neurological circuit data (e.g., inactivation studies). We conclude with a comparison of the new model with existing models of automatic sequence production and discuss a possible new role for the BG in automaticity and its implication for Parkinson's disease.

  8. An integrated production, inventory and preventive maintenance model for a multi-product production system

    International Nuclear Information System (INIS)

    Liu, Xuejuan; Wang, Wenbin; Peng, Rui

    2015-01-01

    This paper considers a production system that can produce multiple products alternately. Products go through the system in a sequence and a complete run of all products forms a production cycle. An integrated production, inventory and preventive maintenance model is constructed, which is characterized by the delay-time concept. Two different situations are studied based on whether the unqualified products and downtime caused by the failures of the system, set-up and preventive maintenance can be ignored or not. Three cases are considered for each situation, depending on the position of the preventive maintenance epochs: the first case, where preventive maintenance is carried out at the end of each production cycle; the second case, where preventive maintenance is carried out at each set-up time of the products; and the third case, where preventive maintenance is carried out at some set-up times only, since it may not always be optimal to carry out preventive maintenance at the end of the production cycle or at each set-up time. The modeling objectives are to find the optimal number of production cycles per year and the optimal position of preventive maintenance that will maximize the expected profit per unit time. Numerical examples, using real data, are presented to illustrate the model. - Highlights: • We propose an integrated economic production quantity and preventive maintenance model. • The situation that multiple products are produced on the same system alternately is studied. • Two situations are studied based on whether the downtime and the product quality can be ignored or not. • We use enumeration method and analytical method to select the optimal preventive maintenance policy, respectively. • We use the delay-time concept to model the preventive maintenance policy

  9. Fission product detection by means of photovoltaic cells

    International Nuclear Information System (INIS)

    Liatard, E.; Akrouf, S.; Bruandet, J.F.; Fontenille, A.; Glasser, F.; Stassi, P.; Tsan Ung Chan

    1988-01-01

    The response of photovoltaic cells to heavy ions and fission products have been tested in-beam. Their main advantages are their extremely low price, their low sensitivity to energetic light ions with respect to fission products, and the possibility to cut and fit them together to any shape without dead zone. The time output signals of a charge sensitive preamplifier connected to these cells allows fast coincidences. A resolution of 12 ns (FWHM) has been measured between two cells. (orig.)

  10. Electrochemical characterisation of solid oxide cell electrodes for hydrogen production

    DEFF Research Database (Denmark)

    Bernuy-Lopez, Carlos; Knibbe, Ruth; He, Zeming

    2011-01-01

    Oxygen electrodes and steam electrodes are designed and tested to develop improved solid oxide electrolysis cells for H2 production with the cell support on the oxygen electrode. The electrode performance is evaluated by impedance spectroscopy testing of symmetric cells at open circuit voltage (OCV...

  11. Method for reducing ammonium and lactate production in cho cells

    DEFF Research Database (Denmark)

    2018-01-01

    The present invention relates to modified producer cells for improved production of therapeutic proteins. Specifically, the inventors have found that removing genes involved in amino acid catabolism in Chinese Hamster Ovary (CHO) cells improves the cell growth and viability and likely also...

  12. Model for fission-product calculations

    International Nuclear Information System (INIS)

    Smith, A.B.

    1984-01-01

    Many fission-product cross sections remain unmeasurable thus considerable reliance must be placed upon calculational interpolation and extrapolation from the few available measured cross sections. The vehicle, particularly for the lighter fission products, is the conventional optical-statistical model. The applied goals generally are: capture cross sections to 7 to 10% accuracies and inelastic-scattering cross sections to 25 to 50%. Comparisons of recent evaluations and experimental results indicate that these goals too often are far from being met, particularly in the area of inelastic scattering, and some of the evaluated fission-product cross sections are simply physically unreasonable. It is difficult to avoid the conclusion that the models employed in many of the evaluations are inappropriate and/or inappropriately used. In order to alleviate the above unfortunate situations, a regional optical-statistical (OM) model was sought with the goal of quantitative prediction of the cross sections of the lighter-mass (Z = 30-51) fission products. The first step toward that goal was the establishment of a reliable experimental data base consisting of energy-averaged neutron total and differential-scattering cross sections. The second step was the deduction of a regional model from the experimental data. It was assumed that a spherical OM is appropriate: a reasonable and practical assumption. The resulting OM then was verified against the measured data base. Finally, the physical character of the regional model is examined

  13. Automatic support for product based workflow design : generation of process models from a product data model

    NARCIS (Netherlands)

    Vanderfeesten, I.T.P.; Reijers, H.A.; Aalst, van der W.M.P.; Vogelaar, J.J.C.L.; Meersman, R.; Dillon, T.; Herrero, P.

    2010-01-01

    Product Based Workflow Design (PBWD) is one of the few scientific methodologies for the (re)design of workflow processes. It is based on an analysis of the product that is produced in the workflow process and derives a process model from the product structure. Until now this derivation has been a

  14. Modeling human neurological disorders with induced pluripotent stem cells.

    Science.gov (United States)

    Imaizumi, Yoichi; Okano, Hideyuki

    2014-05-01

    Human induced pluripotent stem (iPS) cells obtained by reprogramming technology are a source of great hope, not only in terms of applications in regenerative medicine, such as cell transplantation therapy, but also for modeling human diseases and new drug development. In particular, the production of iPS cells from the somatic cells of patients with intractable diseases and their subsequent differentiation into cells at affected sites (e.g., neurons, cardiomyocytes, hepatocytes, and myocytes) has permitted the in vitro construction of disease models that contain patient-specific genetic information. For example, disease-specific iPS cells have been established from patients with neuropsychiatric disorders, including schizophrenia and autism, as well as from those with neurodegenerative diseases, including Parkinson's disease and Alzheimer's disease. A multi-omics analysis of neural cells originating from patient-derived iPS cells may thus enable investigators to elucidate the pathogenic mechanisms of neurological diseases that have heretofore been unknown. In addition, large-scale screening of chemical libraries with disease-specific iPS cells is currently underway and is expected to lead to new drug discovery. Accordingly, this review outlines the progress made via the use of patient-derived iPS cells toward the modeling of neurological disorders, the testing of existing drugs, and the discovery of new drugs. The production of human induced pluripotent stem (iPS) cells from the patients' somatic cells and their subsequent differentiation into specific cells have permitted the in vitro construction of disease models that contain patient-specific genetic information. Furthermore, innovations of gene-editing technologies on iPS cells are enabling new approaches for illuminating the pathogenic mechanisms of human diseases. In this review article, we outlined the current status of neurological diseases-specific iPS cell research and described recently obtained

  15. MANUFACTURING NATURAL KILLER CELLS AS MEDICINAL PRODUCTS

    Directory of Open Access Journals (Sweden)

    Christian CHABANNON

    2016-11-01

    Full Text Available Natural Killer (NK cells are Innate Lymphoid Cells (ILC with cytotoxic and regulatory properties. Their functions are tightly regulated by an array of inhibitory and activating receptors, and their mechanisms of activation strongly differ from antigen recognition in the context of HLA presentation as needed for T-cell activation. NK cells thus offer unique opportunities for new and improved therapeutic manipulation, either in vivo or in vitro, in a variety of human diseases, including cancers. NK cell activity can possibly be modulated in vivo through direct or indirect actions exerted by small molecules or monoclonal antibodies. NK cells can also be adoptively transferred following more or less substantial modifications through cell and gene manufacturing, in order to empower them with new or improved functions and ensure their controlled persistence and activity in the recipient. In the present review, we will focus on the technological and regulatory challenges of NK cell manufacturing, and discuss conditions in which these innovative cellular therapies can be brought to the clinic.

  16. Design of neural network model-based controller in a fed-batch microbial electrolysis cell reactor for bio-hydrogen gas production

    Science.gov (United States)

    Azwar; Hussain, M. A.; Abdul-Wahab, A. K.; Zanil, M. F.; Mukhlishien

    2018-03-01

    One of major challenge in bio-hydrogen production process by using MEC process is nonlinear and highly complex system. This is mainly due to the presence of microbial interactions and highly complex phenomena in the system. Its complexity makes MEC system difficult to operate and control under optimal conditions. Thus, precise control is required for the MEC reactor, so that the amount of current required to produce hydrogen gas can be controlled according to the composition of the substrate in the reactor. In this work, two schemes for controlling the current and voltage of MEC were evaluated. The controllers evaluated are PID and Inverse neural network (NN) controller. The comparative study has been carried out under optimal condition for the production of bio-hydrogen gas wherein the controller output is based on the correlation of optimal current and voltage to the MEC. Various simulation tests involving multiple set-point changes and disturbances rejection have been evaluated and the performances of both controllers are discussed. The neural network-based controller results in fast response time and less overshoots while the offset effects are minimal. In conclusion, the Inverse neural network (NN)-based controllers provide better control performance for the MEC system compared to the PID controller.

  17. Production of pancreatic hormone-expressing endocrine cells from human embryonic stem cells.

    Science.gov (United States)

    D'Amour, Kevin A; Bang, Anne G; Eliazer, Susan; Kelly, Olivia G; Agulnick, Alan D; Smart, Nora G; Moorman, Mark A; Kroon, Evert; Carpenter, Melissa K; Baetge, Emmanuel E

    2006-11-01

    Of paramount importance for the development of cell therapies to treat diabetes is the production of sufficient numbers of pancreatic endocrine cells that function similarly to primary islets. We have developed a differentiation process that converts human embryonic stem (hES) cells to endocrine cells capable of synthesizing the pancreatic hormones insulin, glucagon, somatostatin, pancreatic polypeptide and ghrelin. This process mimics in vivo pancreatic organogenesis by directing cells through stages resembling definitive endoderm, gut-tube endoderm, pancreatic endoderm and endocrine precursor--en route to cells that express endocrine hormones. The hES cell-derived insulin-expressing cells have an insulin content approaching that of adult islets. Similar to fetal beta-cells, they release C-peptide in response to multiple secretory stimuli, but only minimally to glucose. Production of these hES cell-derived endocrine cells may represent a critical step in the development of a renewable source of cells for diabetes cell therapy.

  18. Design, product structuring and modelling of mechatronic products and systems

    DEFF Research Database (Denmark)

    Conrad, Finn; Sørensen, Torben

    2003-01-01

    Information Technology offers software and hardware for improvement of the engineering design, structuring and control systems, and industrial applications. The latest progress in IT makes integration of an overall design and manufacturing IT- concept feasible and commercially attractive. An IT......-tool concept for modelling, simulation and design of mechatronic products and systems is proposed in this paper. It built on results from a Danish mechatronic research program on intelligent motion control as well as from the Esprit project SWING on IT-tools for rapid prototyping of fluid power components...

  19. Product modelling: '20 years of stalemate'?

    DEFF Research Database (Denmark)

    Galle, Per

    1998-01-01

    In a recent special issue of Design Studies Michael Ramscar, John Lee, and Helen Pain level a severe criticism against a field of research known as product modeling; a criticism that would be rather damaging if it were based on cogent arguments. I shall argue in this paper that it is not....

  20. Product modelling in the seafood industry

    DEFF Research Database (Denmark)

    Jonsdottir, Stella; Vesterager, Johan

    1997-01-01

    driven and proactive to comply with the increasing competition, in such a way that the fish processor issues new products covering both the current and especially latent future consumer demands. This implies a need for new systematic approaches in the NPD as procedures and tools, which integrate...... based integration obtained by the CE approach and tools. It is described how the knowledge and information of a seafood product can be modelled by using object oriented techniques.......The paper addresses the aspects of Concurrent Engineering (CE) as a means to obtain integrated product development in the seafood industry. It is assumed that the future New Product Development (NPD) in seafood industry companies will shift from being retailer driven and reactive to be more company...

  1. Pebble Bed Reactor Dust Production Model

    Energy Technology Data Exchange (ETDEWEB)

    Abderrafi M. Ougouag; Joshua J. Cogliati

    2008-09-01

    The operation of pebble bed reactors, including fuel circulation, can generate graphite dust, which in turn could be a concern for internal components; and to the near field in the remote event of a break in the coolant circuits. The design of the reactor system must, therefore, take the dust into account and the operation must include contingencies for dust removal and for mitigation of potential releases. Such planning requires a proper assessment of the dust inventory. This paper presents a predictive model of dust generation in an operating pebble bed with recirculating fuel. In this preliminary work the production model is based on the use of the assumption of proportionality between the dust production and the normal force and distance traveled. The model developed in this work uses the slip distances and the inter-pebble forces computed by the authors’ PEBBLES. The code, based on the discrete element method, simulates the relevant static and kinetic friction interactions between the pebbles as well as the recirculation of the pebbles through the reactor vessel. The interaction between pebbles and walls of the reactor vat is treated using the same approach. The amount of dust produced is proportional to the wear coefficient for adhesive wear (taken from literature) and to the slip volume, the product of the contact area and the slip distance. The paper will compare the predicted volume with the measured production rates. The simulation tallies the dust production based on the location of creation. Two peak production zones from intra pebble forces are predicted within the bed. The first zone is located near the pebble inlet chute due to the speed of the dropping pebbles. The second peak zone occurs lower in the reactor with increased pebble contact force due to the weight of supported pebbles. This paper presents the first use of a Discrete Element Method simulation of pebble bed dust production.

  2. Pebble Bed Reactor Dust Production Model

    International Nuclear Information System (INIS)

    Abderrafi M. Ougouag; Joshua J. Cogliati

    2008-01-01

    The operation of pebble bed reactors, including fuel circulation, can generate graphite dust, which in turn could be a concern for internal components; and to the near field in the remote event of a break in the coolant circuits. The design of the reactor system must, therefore, take the dust into account and the operation must include contingencies for dust removal and for mitigation of potential releases. Such planning requires a proper assessment of the dust inventory. This paper presents a predictive model of dust generation in an operating pebble bed with recirculating fuel. In this preliminary work the production model is based on the use of the assumption of proportionality between the dust production and the normal force and distance traveled. The model developed in this work uses the slip distances and the inter-pebble forces computed by the authors PEBBLES. The code, based on the discrete element method, simulates the relevant static and kinetic friction interactions between the pebbles as well as the recirculation of the pebbles through the reactor vessel. The interaction between pebbles and walls of the reactor vat is treated using the same approach. The amount of dust produced is proportional to the wear coefficient for adhesive wear (taken from literature) and to the slip volume, the product of the contact area and the slip distance. The paper will compare the predicted volume with the measured production rates. The simulation tallies the dust production based on the location of creation. Two peak production zones from intra pebble forces are predicted within the bed. The first zone is located near the pebble inlet chute due to the speed of the dropping pebbles. The second peak zone occurs lower in the reactor with increased pebble contact force due to the weight of supported pebbles. This paper presents the first use of a Discrete Element Method simulation of pebble bed dust production

  3. Regulation of Cell and Gene Therapy Medicinal Products in Taiwan.

    Science.gov (United States)

    Lin, Yi-Chu; Wang, Po-Yu; Tsai, Shih-Chih; Lin, Chien-Liang; Tai, Hsuen-Yung; Lo, Chi-Fang; Wu, Shiow-Ing; Chiang, Yu-Mei; Liu, Li-Ling

    2015-01-01

    Owing to the rapid and mature development of emerging biotechnology in the fields of cell culture, cell preservation, and recombinant DNA technology, more and more cell or gene medicinal therapy products have been approved for marketing, to treat serious diseases which have been challenging to treat with current medical practice or medicine. This chapter will briefly introduce the Taiwan Food and Drug Administration (TFDA) and elaborate regulation of cell and gene therapy medicinal products in Taiwan, including regulatory history evolution, current regulatory framework, application and review procedures, and relevant jurisdictional issues. Under the promise of quality, safety, and efficacy of medicinal products, it is expected the regulation and environment will be more flexible, streamlining the process of the marketing approval of new emerging cell or gene therapy medicinal products and providing diverse treatment options for physicians and patients.

  4. Monte Carlo modeling of in vivo protoporphyrin IX fluorescence and singlet oxygen production during photodynamic therapy for patients presenting with superficial basal cell carcinomas

    Science.gov (United States)

    Valentine, Ronan M.; Brown, C. Tom A.; Moseley, Harry; Ibbotson, Sally; Wood, Kenny

    2011-04-01

    We present protoporphyrin IX (PpIX) fluorescence measurements acquired from patients presenting with superficial basal cell carcinoma during photodynamic therapy (PDT) treatment, facilitating in vivo photobleaching to be monitored. Monte Carlo (MC) simulations, taking into account photobleaching, are performed on a three-dimensional cube grid, which represents the treatment geometry. Consequently, it is possible to determine the spatial and temporal changes to the origin of collected fluorescence and generated singlet oxygen. From our clinical results, an in vivo photobleaching dose constant, β of 5-aminolaevulinic acid-induced PpIX fluorescence is found to be 14 +/- 1 J/cm2. Results from our MC simulations suggest that an increase from our typical administered treatment light dose of 75-150 J/cm2 could increase the effective PDT treatment initially achieved at a depth of 2.7-3.3 mm in the tumor, respectively. Moreover, this increase reduces the surface PpIX fluorescence from 0.00012 to 0.000003 of the maximum value recorded before treatment. The recommendation of administrating a larger light dose, which advocates an increase in the treatment time after surface PpIX fluorescence has diminished, remains valid for different sets of optical properties and therefore should have a beneficial outcome on the total treatment effect.

  5. Alternative methods of modeling wind generation using production costing models

    International Nuclear Information System (INIS)

    Milligan, M.R.; Pang, C.K.

    1996-08-01

    This paper examines the methods of incorporating wind generation in two production costing models: one is a load duration curve (LDC) based model and the other is a chronological-based model. These two models were used to evaluate the impacts of wind generation on two utility systems using actual collected wind data at two locations with high potential for wind generation. The results are sensitive to the selected wind data and the level of benefits of wind generation is sensitive to the load forecast. The total production cost over a year obtained by the chronological approach does not differ significantly from that of the LDC approach, though the chronological commitment of units is more realistic and more accurate. Chronological models provide the capability of answering important questions about wind resources which are difficult or impossible to address with LDC models

  6. B cell depletion reduces T cell activation in pancreatic islets in a murine autoimmune diabetes model.

    Science.gov (United States)

    Da Rosa, Larissa C; Boldison, Joanne; De Leenheer, Evy; Davies, Joanne; Wen, Li; Wong, F Susan

    2018-06-01

    Type 1 diabetes is a T cell-mediated autoimmune disease characterised by the destruction of beta cells in the islets of Langerhans, resulting in deficient insulin production. B cell depletion therapy has proved successful in preventing diabetes and restoring euglycaemia in animal models of diabetes, as well as in preserving beta cell function in clinical trials in the short term. We aimed to report a full characterisation of B cell kinetics post B cell depletion, with a focus on pancreatic islets. Transgenic NOD mice with a human CD20 transgene expressed on B cells were injected with an anti-CD20 depleting antibody. B cells were analysed using multivariable flow cytometry. There was a 10 week delay in the onset of diabetes when comparing control and experimental groups, although the final difference in the diabetes incidence, following prolonged observation, was not statistically significant (p = 0.07). The co-stimulatory molecules CD80 and CD86 were reduced on stimulation of B cells during B cell depletion and repopulation. IL-10-producing regulatory B cells were not induced in repopulated B cells in the periphery, post anti-CD20 depletion. However, the early depletion of B cells had a marked effect on T cells in the local islet infiltrate. We demonstrated a lack of T cell activation, specifically with reduced CD44 expression and effector function, including IFN-γ production from both CD4 + and CD8 + T cells. These CD8 + T cells remained altered in the pancreatic islets long after B cell depletion and repopulation. Our findings suggest that B cell depletion can have an impact on T cell regulation, inducing a durable effect that is present long after repopulation. We suggest that this local effect of reducing autoimmune T cell activity contributes to delay in the onset of autoimmune diabetes.

  7. Critical role of NKT cells in posttransplant alloantibody production.

    Science.gov (United States)

    Zimmerer, J M; Swamy, P; Sanghavi, P B; Wright, C L; Abdel-Rasoul, M; Elzein, S M; Brutkiewicz, R R; Bumgardner, G L

    2014-11-01

    We previously reported that posttransplant alloantibody production in CD8-deficient hosts is IL-4+ CD4+ T cell-dependent and IgG1 isotype-dominant. The current studies investigated the hypothesis that IL-4-producing natural killer T cells (NKT cells) contribute to maximal alloantibody production. To investigate this, alloantibody levels were examined in CD8-deficient WT, CD1d KO and Jα18 KO transplant recipients. We found that the magnitude of IgG1 alloantibody production was critically dependent on the presence of type I NKT cells, which are activated by day 1 posttransplant. Unexpectedly, type I NKT cell contribution to enhanced IgG1 alloantibody levels was interferon-γ-dependent and IL-4-independent. Cognate interactions between type I NKT and B cells alone do not stimulate alloantibody production. Instead, NKT cells appear to enhance maturation of IL-4+ CD4+ T cells. To our knowledge, this is the first report to substantiate a critical role for type I NKT cells in enhancing in vivo antibody production in response to endogenous antigenic stimuli. © Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.

  8. Beneficial Role of Some Natural Products to Attenuate the Diabetic Cardiomyopathy Through Nrf2 Pathway in Cell Culture and Animal Models.

    Science.gov (United States)

    Sathibabu Uddandrao, V V; Brahmanaidu, Parim; Nivedha, P R; Vadivukkarasi, S; Saravanan, Ganapathy

    2017-10-27

    Diabetic cardiomyopathy, as one of the main cardiac complications in diabetic patients, is identified to connect with oxidative stress that is due to interruption in balance between reactive oxygen species or/and reactive nitrogen species generation and their clearance by antioxidant protection systems. Transcription factor the nuclear factor erythroid 2-related factor 2 (Nrf2) plays a significant role in maintaining the oxidative homeostasis by regulating multiple downstream antioxidants. The Nrf2 plays a significant role in ARE-mediated basal and inducible expression of more than 200 genes that can be grouped into numerous categories as well as antioxidant genes and phase II detoxifying enzymes. On the other hand, activation of Nrf2 by natural and synthetic therapeutics or antioxidants has been revealed effective for the prevention and treatment of toxicities and diseases connected with oxidative stress. Hence, recently focus has been shifted toward plants and plant-based medicines in curing such chronic diseases, as they are supposed to be less toxic. In this review, we focused on the role of some natural products on diabetic cardiomyopathy through Nrf2 pathway.

  9. Deconstructing stem cell population heterogeneity: Single-cell analysis and modeling approaches

    Science.gov (United States)

    Wu, Jincheng; Tzanakakis, Emmanuel S.

    2014-01-01

    Isogenic stem cell populations display cell-to-cell variations in a multitude of attributes including gene or protein expression, epigenetic state, morphology, proliferation and proclivity for differentiation. The origins of the observed heterogeneity and its roles in the maintenance of pluripotency and the lineage specification of stem cells remain unclear. Addressing pertinent questions will require the employment of single-cell analysis methods as traditional cell biochemical and biomolecular assays yield mostly population-average data. In addition to time-lapse microscopy and flow cytometry, recent advances in single-cell genomic, transcriptomic and proteomic profiling are reviewed. The application of multiple displacement amplification, next generation sequencing, mass cytometry and spectrometry to stem cell systems is expected to provide a wealth of information affording unprecedented levels of multiparametric characterization of cell ensembles under defined conditions promoting pluripotency or commitment. Establishing connections between single-cell analysis information and the observed phenotypes will also require suitable mathematical models. Stem cell self-renewal and differentiation are orchestrated by the coordinated regulation of subcellular, intercellular and niche-wide processes spanning multiple time scales. Here, we discuss different modeling approaches and challenges arising from their application to stem cell populations. Integrating single-cell analysis with computational methods will fill gaps in our knowledge about the functions of heterogeneity in stem cell physiology. This combination will also aid the rational design of efficient differentiation and reprogramming strategies as well as bioprocesses for the production of clinically valuable stem cell derivatives. PMID:24035899

  10. Coordinated supply chain dynamic production planning model

    Science.gov (United States)

    Chandra, Charu; Grabis, Janis

    2001-10-01

    Coordination of different and often contradicting interests of individual supply chain members is one of the important issues in supply chain management because the individual members can not succeed without success of the supply chain and vice versa. This paper investigates a supply chain dynamic production planning problem with emphasis on coordination. A planning problem is formally described using a supply chain kernel, which defines supply chain configuration, management policies, available resources and objectives both at supply chain or macro and supply chain member or micro levels. The coordinated model is solved in order to balance decisions made at the macro and micro levels and members' profitability is used as the coordination criterion. The coordinated model is used to determine inventory levels and production capacity across the supply chain. Application of the coordinated model distributes costs burden uniformly among supply chain members and preserves overall efficiency of the supply chain. Influence of the demand series uncertainty is investigated. The production planning model is a part of the integrated supply chain decision modeling system, which is shared among the supply chain members across the Internet.

  11. Engineering models and methods for industrial cell control

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen Birk; Alting, Leo

    1997-01-01

    This paper is concerned with the engineering, i.e. the designing and making, of industrial cell control systems. The focus is on automated robot welding cells in the shipbuilding industry. The industrial research project defines models and methods for design and implemen-tation of computer based...... SHIPYARD.It is concluded that cell control technology provides for increased performance in production systems, and that the Cell Control Engineering concept reduces the effort for providing and operating high quality and high functionality cell control solutions for the industry....... control and monitor-ing systems for production cells. The project participants are The Danish Academy of Technical Sciences, the Institute of Manufacturing Engineering at the Technical University of Denmark and ODENSE STEEL SHIPYARD Ltd.The manufacturing environment and the current practice...

  12. Reference model for apparel product development

    Directory of Open Access Journals (Sweden)

    Isabel Cristina Moretti

    2017-03-01

    Full Text Available The purpose of this paper was to develop a reference model for the implementation of the process of product development (PDP for apparel. The tool was developed through an interactive process of comparison between theoretical. Managers in companies and professionals working in this market can utilize the reference model as a source for the organization and improvement of the PDP for apparel and the universities as a reference source for systematized teaching of this process. This model represents the first comprehensive attempt to develop an instrument at a detailed level (macro phases, phases, activities, inputs and outputs at each stage and at the gates to systematize the PDP process for fashion products and to consider its particularities.

  13. Matrix factorizations, minimal models and Massey products

    International Nuclear Information System (INIS)

    Knapp, Johanna; Omer, Harun

    2006-01-01

    We present a method to compute the full non-linear deformations of matrix factorizations for ADE minimal models. This method is based on the calculation of higher products in the cohomology, called Massey products. The algorithm yields a polynomial ring whose vanishing relations encode the obstructions of the deformations of the D-branes characterized by these matrix factorizations. This coincides with the critical locus of the effective superpotential which can be computed by integrating these relations. Our results for the effective superpotential are in agreement with those obtained from solving the A-infinity relations. We point out a relation to the superpotentials of Kazama-Suzuki models. We will illustrate our findings by various examples, putting emphasis on the E 6 minimal model

  14. Cell fusion in tumor progression: the isolation of cell fusion products by physical methods

    Directory of Open Access Journals (Sweden)

    Vincitorio Massimo

    2011-09-01

    Full Text Available Abstract Background Cell fusion induced by polyethylene glycol (PEG is an efficient but poorly controlled procedure for obtaining somatic cell hybrids used in gene mapping, monoclonal antibody production, and tumour immunotherapy. Genetic selection techniques and fluorescent cell sorting are usually employed to isolate cell fusion products, but both procedures have several drawbacks. Results Here we describe a simple improvement in PEG-mediated cell fusion that was obtained by modifying the standard single-step procedure. We found that the use of two PEG undertreatments obtains a better yield of cell fusion products than the standard method, and most of these products are bi- or trinucleated polykaryocytes. Fusion rate was quantified using fluorescent cell staining microscopy. We used this improved cell fusion and cell isolation method to compare giant cells obtained in vitro and giant cells obtained in vivo from patients with Hodgkin's disease and erythroleukemia. Conclusions In the present study we show how to improve PEG-mediated cell fusion and that cell separation by velocity sedimentation offers a simple alternative for the efficient purification of cell fusion products and to investigate giant cell formation in tumor development.

  15. Effects of interleukin-8 on estradiol and progesterone production by bovine granulosa cells from large follicles and progesterone production by luteinizing granulosa cells in culture.

    Science.gov (United States)

    Shimizu, Takashi; Kaji, Ayami; Murayama, Chiaki; Magata, Fumie; Shirasuna, Koumei; Wakamiya, Kaori; Okuda, Kiyoshi; Miyamoto, Akio

    2012-01-01

    Interleukin 8 (IL-8) is a chemoattractant involved in the recruitment and activation of neutrophils and is associated with the ovulate process. We examined the possible role of IL-8 in steroid production by bovine granulosa cells before and after ovulation. The concentration of IL-8 in the follicular fluid of estrogen-active dominant (EAD) and pre-ovulatory follicles (POF) was higher than that of small follicles (SF). CXCR1 mRNA expression was higher in the granulosa cells of EAD and POF than that of SF. In contrast, CXCR2 mRNA expression was lower in granulosa cells of EAD and POF than in SF. IL-8 inhibited estradiol (E2) production in follicle-stimulating hormone (FSH)-treated granulosa cells at 48 h of culture. IL-8 also suppressed CYP19A1 mRNA expression in FSH-treated granulosa cells. IL-8 stimulated progesterone (P4) production in luteinizing hormone (LH)-treated granulosa cells at 48 h of culture. Although IL-8 did not alter the expression of genes associated with P4 production, it induced StAR protein expression in LH-treated granulosa cells. The expression of CXCR1 mRNA in corpus luteum (CL) did not change during the luteal phase. In contrast, the expression of CXCR2 mRNA in middle CL was significantly higher than in early and regression CL during the luteal phase. In luteinizing granulosa cells, an in vitro model of granulosa cell luteinization, CXCR2 mRNA expression was downregulated, whereas CXCR1 mRNA expression was unchanged. IL-8 also stimulated P4 production in luteinizing granulosa cells. These data provide evidence that IL-8 functions not only as a chemokine, but also act as a regulator of steroid synthesis in granulosa cells to promote luteinization after ovulation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Measuring productivity differences in equilibrium search models

    DEFF Research Database (Denmark)

    Lanot, Gauthier; Neumann, George R.

    1996-01-01

    Equilibrium search models require unobserved heterogeneity in productivity to fit observed wage distribution data, but provide no guidance about the location parameter of the heterogeneity. In this paper we show that the location of the productivity heterogeneity implies a mode in a kernel density...... estimate of the wage distribution. The number of such modes and their location are identified using bump hunting techniques due to Silverman (1981). These techniques are applied to Danish panel data on workers and firms. These estimates are used to assess the importance of employer wage policy....

  17. Modeling the Shapes of Cells

    Science.gov (United States)

    Garimella, Umadevi I.; Robertson, Belinda M.

    2015-01-01

    A solid understanding of the structure and function of cells can help establish the foundation for learning advanced concepts in the biological sciences. The concept of the cell is introduced in middle school life science courses and is continued at the undergraduate level in college (NRC 2012; Reece et al. 2014). Cells are introduced to students…

  18. Testing Software Development Project Productivity Model

    Science.gov (United States)

    Lipkin, Ilya

    Software development is an increasingly influential factor in today's business environment, and a major issue affecting software development is how an organization estimates projects. If the organization underestimates cost, schedule, and quality requirements, the end results will not meet customer needs. On the other hand, if the organization overestimates these criteria, resources that could have been used more profitably will be wasted. There is no accurate model or measure available that can guide an organization in a quest for software development, with existing estimation models often underestimating software development efforts as much as 500 to 600 percent. To address this issue, existing models usually are calibrated using local data with a small sample size, with resulting estimates not offering improved cost analysis. This study presents a conceptual model for accurately estimating software development, based on an extensive literature review and theoretical analysis based on Sociotechnical Systems (STS) theory. The conceptual model serves as a solution to bridge organizational and technological factors and is validated using an empirical dataset provided by the DoD. Practical implications of this study allow for practitioners to concentrate on specific constructs of interest that provide the best value for the least amount of time. This study outlines key contributing constructs that are unique for Software Size E-SLOC, Man-hours Spent, and Quality of the Product, those constructs having the largest contribution to project productivity. This study discusses customer characteristics and provides a framework for a simplified project analysis for source selection evaluation and audit task reviews for the customers and suppliers. Theoretical contributions of this study provide an initial theory-based hypothesized project productivity model that can be used as a generic overall model across several application domains such as IT, Command and Control

  19. Streamlining environmental product declarations: a stage model

    Science.gov (United States)

    Lefebvre, Elisabeth; Lefebvre, Louis A.; Talbot, Stephane; Le Hen, Gael

    2001-02-01

    General public environmental awareness and education is increasing, therefore stimulating the demand for reliable, objective and comparable information about products' environmental performances. The recently published standard series ISO 14040 and ISO 14025 are normalizing the preparation of Environmental Product Declarations (EPDs) containing comprehensive information relevant to a product's environmental impact during its life cycle. So far, only a few environmentally leading manufacturing organizations have experimented the preparation of EPDs (mostly from Europe), demonstrating its great potential as a marketing weapon. However the preparation of EPDs is a complex process, requiring collection and analysis of massive amounts of information coming from disparate sources (suppliers, sub-contractors, etc.). In a foreseeable future, the streamlining of the EPD preparation process will require product manufacturers to adapt their information systems (ERP, MES, SCADA) in order to make them capable of gathering, and transmitting the appropriate environmental information. It also requires strong functional integration all along the product supply chain in order to ensure that all the information is made available in a standardized and timely manner. The goal of the present paper is two fold: first to propose a transitional model towards green supply chain management and EPD preparation; second to identify key technologies and methodologies allowing to streamline the EPD process and subsequently the transition toward sustainable product development

  20. Declarative Modeling for Production Order Portfolio Scheduling

    Directory of Open Access Journals (Sweden)

    Banaszak Zbigniew

    2014-12-01

    Full Text Available A declarative framework enabling to determine conditions as well as to develop decision-making software supporting small- and medium-sized enterprises aimed at unique, multi-project-like and mass customized oriented production is discussed. A set of unique production orders grouped into portfolio orders is considered. Operations executed along different production orders share available resources following a mutual exclusion protocol. A unique product or production batch is completed while following a given activity’s network order. The problem concerns scheduling a newly inserted project portfolio subject to constraints imposed by a multi-project environment The answers sought are: Can a given project portfolio specified by its cost and completion time be completed within the assumed time period in a manufacturing system in hand? Which manufacturing system capability guarantees the completion of a given project portfolio ordered under assumed cost and time constraints? The considered problems regard finding a computationally effective approach aimed at simultaneous routing and allocation as well as batching and scheduling of a newly ordered project portfolio subject to constraints imposed by a multi-project environment. The main objective is to provide a declarative model enabling to state a constraint satisfaction problem aimed at multi-project-like and mass customized oriented production scheduling. Multiple illustrative examples are discussed.

  1. Multi-stage high cell continuous fermentation for high productivity and titer.

    Science.gov (United States)

    Chang, Ho Nam; Kim, Nag-Jong; Kang, Jongwon; Jeong, Chang Moon; Choi, Jin-dal-rae; Fei, Qiang; Kim, Byoung Jin; Kwon, Sunhoon; Lee, Sang Yup; Kim, Jungbae

    2011-05-01

    We carried out the first simulation on multi-stage continuous high cell density culture (MSC-HCDC) to show that the MSC-HCDC can achieve batch/fed-batch product titer with much higher productivity to the fed-batch productivity using published fermentation kinetics of lactic acid, penicillin and ethanol. The system under consideration consists of n-serially connected continuous stirred-tank reactors (CSTRs) with either hollow fiber cell recycling or cell immobilization for high cell-density culture. In each CSTR substrate supply and product removal are possible. Penicillin production is severely limited by glucose metabolite repression that requires multi-CSTR glucose feeding. An 8-stage C-HCDC lactic acid fermentation resulted in 212.9 g/L of titer and 10.6 g/L/h of productivity, corresponding to 101 and 429% of the comparable lactic acid fed-batch, respectively. The penicillin production model predicted 149% (0.085 g/L/h) of productivity in 8-stage C-HCDC with 40 g/L of cell density and 289% of productivity (0.165 g/L/h) in 7-stage C-HCDC with 60 g/L of cell density compared with referring batch cultivations. A 2-stage C-HCDC ethanol experimental run showed 107% titer and 257% productivity of the batch system having 88.8 g/L of titer and 3.7 g/L/h of productivity. MSC-HCDC can give much higher productivity than batch/fed-batch system, and yield a several percentage higher titer as well. The productivity ratio of MSC-HCDC over batch/fed-batch system is given as a multiplication of system dilution rate of MSC-HCDC and cycle time of batch/fed-batch system. We suggest MSC-HCDC as a new production platform for various fermentation products including monoclonal antibody.

  2. A temperature-controlled photoelectrochemical cell for quantitative product analysis

    Science.gov (United States)

    Corson, Elizabeth R.; Creel, Erin B.; Kim, Youngsang; Urban, Jeffrey J.; Kostecki, Robert; McCloskey, Bryan D.

    2018-05-01

    In this study, we describe the design and operation of a temperature-controlled photoelectrochemical cell for analysis of gaseous and liquid products formed at an illuminated working electrode. This cell is specifically designed to quantitatively analyze photoelectrochemical processes that yield multiple gas and liquid products at low current densities and exhibit limiting reactant concentrations that prevent these processes from being studied in traditional single chamber electrolytic cells. The geometry of the cell presented in this paper enables front-illumination of the photoelectrode and maximizes the electrode surface area to electrolyte volume ratio to increase liquid product concentration and hence enhances ex situ spectroscopic sensitivity toward them. Gas is bubbled through the electrolyte in the working electrode chamber during operation to maintain a saturated reactant concentration and to continuously mix the electrolyte. Gaseous products are detected by an in-line gas chromatograph, and liquid products are analyzed ex situ by nuclear magnetic resonance. Cell performance was validated by examining carbon dioxide reduction on a silver foil electrode, showing comparable results both to those reported in the literature and identical experiments performed in a standard parallel-electrode electrochemical cell. To demonstrate a photoelectrochemical application of the cell, CO2 reduction experiments were carried out on a plasmonic nanostructured silver photocathode and showed different product distributions under dark and illuminated conditions.

  3. Models and Modelling Tools for Chemical Product and Process Design

    DEFF Research Database (Denmark)

    Gani, Rafiqul

    2016-01-01

    The design, development and reliability of a chemical product and the process to manufacture it, need to be consistent with the end-use characteristics of the desired product. One of the common ways to match the desired product-process characteristics is through trial and error based experiments......-based framework is that in the design, development and/or manufacturing of a chemical product-process, the knowledge of the applied phenomena together with the product-process design details can be provided with diverse degrees of abstractions and details. This would allow the experimental resources...... to be employed for validation and fine-tuning of the solutions from the model-based framework, thereby, removing the need for trial and error experimental steps. Also, questions related to economic feasibility, operability and sustainability, among others, can be considered in the early stages of design. However...

  4. Regulatory Oversight of Cell and Gene Therapy Products in Canada.

    Science.gov (United States)

    Ridgway, Anthony; Agbanyo, Francisca; Wang, Jian; Rosu-Myles, Michael

    2015-01-01

    Health Canada regulates gene therapy products and many cell therapy products as biological drugs under the Canadian Food and Drugs Act and its attendant regulations. Cellular products that meet certain criteria, including minimal manipulation and homologous use, may be subjected to a standards-based approach under the Safety of Human Cells, Tissues and Organs for Transplantation Regulations. The manufacture and clinical testing of cell and gene therapy products (CGTPs) presents many challenges beyond those for protein biologics. Cells cannot be subjected to pathogen removal or inactivation procedures and must frequently be administered shortly after final formulation. Viral vector design and manufacturing control are critically important to overall product quality and linked to safety and efficacy in patients through concerns such as replication competence, vector integration, and vector shedding. In addition, for many CGTPs, the value of nonclinical studies is largely limited to providing proof of concept, and the first meaningful data relating to appropriate dosing, safety parameters, and validity of surrogate or true determinants of efficacy must come from carefully designed clinical trials in patients. Addressing these numerous challenges requires application of various risk mitigation strategies and meeting regulatory expectations specifically adapted to the product types. Regulatory cooperation and harmonisation at an international level are essential for progress in the development and commercialisation of these products. However, particularly in the area of cell therapy, new regulatory paradigms may be needed to harness the benefits of clinical progress in situations where the resources and motivation to pursue a typical drug product approval pathway may be lacking.

  5. Nanocluster production for solar cell applications

    International Nuclear Information System (INIS)

    Al Dosari, Haila M.; Ayesh, Ahmad I.

    2013-01-01

    This research focuses on the fabrication and characterization of silver (Ag) and silicon (Si) nanoclusters that might be used for solar cell applications. Silver and silicon nanoclusters have been synthesized by means of dc magnetron sputtering and inert gas condensation inside an ultra-high vacuum compatible system. We have found that nanocluster size distributions can be tuned by various source parameters, such as the sputtering discharge power, flow rate of argon inert gas, and aggregation length. Quadrupole mass filter and transmission electron microscopy were used to evaluate the size distribution of Ag and Si nanoclusters. Ag nanoclusters with average size in the range of 3.6–8.3 nm were synthesized (herein size refers to the nanocluster diameter), whereas Si nanoclusters' average size was controlled to range between 2.9 and 7.4 nm by controlling the source parameters. This work illustrates the ability of controlling the Si and Ag nanoclusters' sizes by proper optimization of the operation conditions. By controlling nanoclusters' sizes, one can alter their surface properties to suit the need to enhance solar cell efficiency. Herein, Ag nanoclusters were deposited on commercial polycrystalline solar cells. Short circuit current (I SC ), open circuit voltage (V OC ), fill factor, and efficiency (η) were obtained under light source with an intensity of 30 mW/cm 2 . A 22.7% enhancement in solar cell efficiency could be measured after deposition of Ag nanoclusters, which demonstrates that Ag nanoclusters generated in this work are useful to enhance solar cell efficiency

  6. Electrocatalysis research for fuel cells and hydrogen production

    CSIR Research Space (South Africa)

    Mathe, MK

    2012-01-01

    Full Text Available The CSIR undertakes research in the Electrocatalysis of fuel cells and for hydrogen production. The Hydrogen South Africa (HySA) strategy supports research on electrocatalysts due to their importance to the national beneficiation strategy. The work...

  7. Enhancement of Diosgenin Production in Plantlet and Cell Cultures ...

    African Journals Online (AJOL)

    Enhancement of Diosgenin Production in Plantlet and Cell Cultures of Dioscorea zingiberensis by Palmarumycin C13 from the Endophytic fungus, Berkleasmium sp. Dzf12. Y Mou, K Zhou, D Xu, R Yu, J Li, C Yin, L Zhou ...

  8. Model of the Product Development Lifecycle.

    Energy Technology Data Exchange (ETDEWEB)

    He, Sunny L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Roe, Natalie H. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wood, Evan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nachtigal, Noel M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Helms, Jovana [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-10-01

    While the increased use of Commercial Off-The-Shelf information technology equipment has presented opportunities for improved cost effectiveness and flexibility, the corresponding loss of control over the product's development creates unique vulnerabilities and security concerns. Of particular interest is the possibility of a supply chain attack. A comprehensive model for the lifecycle of hardware and software products is proposed based on a survey of existing literature from academic, government, and industry sources. Seven major lifecycle stages are identified and defined: (1) Requirements, (2) Design, (3) Manufacturing for hardware and Development for software, (4) Testing, (5) Distribution, (6) Use and Maintenance, and (7) Disposal. The model is then applied to examine the risk of attacks at various stages of the lifecycle.

  9. Modelling the behaviour of organic degradation products

    International Nuclear Information System (INIS)

    Cross, J.E.; Ewart, F.T.; Greenfield, B.F.

    1989-03-01

    Results are presented from recent studies at Harwell which show that the degradation products which are formed when certain organic waste materials are exposed to the alkaline conditions typical of a cementitious environment, can enhance the solubility of plutonium, even at pH values as high as 12, by significant factors. Characterisation of the degradation products has been undertaken but the solubility enhancement does not appear to be related to the concentration of any of the major organic species that have been identified in the solutions. While it has not been possible to identify by analysis the organic ligand responsible for the increased solubility of plutonium, the behaviour of D-Saccharic acid does approach the behaviour of the degradation products. The PHREEQE code has been used to simulate the solubility of plutonium in the presence of D-Saccharic acid and other model degradation products, in order to explain the solubility enhancement. The extrapolation of the experimental conditions to the repository is the major objective, but in this work the ability of a model to predict the behaviour of plutonium over a range of experimental conditions has been tested. (author)

  10. Modelling Fungal Fermentations for Enzyme Production

    DEFF Research Database (Denmark)

    Albæk, Mads Orla; Gernaey, Krist; Hansen, Morten S.

    We have developed a process model of fungal fed-batch fermentations for enzyme production. In these processes, oxygen transfer rate is limiting and controls the substrate feeding rate. The model has been shown to describe cultivations of both Aspergillus oryzae and Trichoderma reesei strains in 550......L stirred tank pilot plant reactors well. For each strain, 8 biological parameters are needed as well as a correlation of viscosity, as viscosity has a major influence on oxygen transfer. The parameters were measured averages of at least 9 batches for each strain. The model is successfully able...... to cover a wide range of process conditions (0.3-2 vvm of aeration, 0.2-10.0 kW/m3 of specific agitation power input, and 0.1-1.3 barg head space pressure). Uncertainty and sensitivity analysis have shown that the uncertainty of the model is mainly due to difficulties surrounding the estimation...

  11. Life cycle assessment of hydrogen production and fuel cell systems

    International Nuclear Information System (INIS)

    Dincer, I.

    2007-01-01

    This paper details life cycle assessment (LCA) of hydrogen production and fuel cell system. LCA is a key tool in hydrogen and fuel cell technologies for design, analysis, development; manufacture, applications etc. Energy efficiencies and greenhouse gases and air pollution emissions have been evaluated in all process steps including crude oil and natural gas pipeline transportation, crude oil distillation, natural gas reprocessing, wind and solar electricity generation , hydrogen production through water electrolysis and gasoline and hydrogen distribution and utilization

  12. Constraining supergravity models from gluino production

    International Nuclear Information System (INIS)

    Barbieri, R.; Gamberini, G.; Giudice, G.F.; Ridolfi, G.

    1988-01-01

    The branching ratios for gluino decays g tilde → qanti qΧ, g tilde → gΧ into a stable undetected neutralino are computed as functions of the relevant parameters of the underlying supergravity theory. A simple way of constraining supergravity models from gluino production emerges. The effectiveness of hadronic versus e + e - colliders in the search for supersymmetry can be directly compared. (orig.)

  13. Modeling of petroleum products demand in France

    International Nuclear Information System (INIS)

    Chauvel, A.; Jamin, F.; Cholet, G.

    1995-01-01

    This project was carried out under the responsibility of the Strategy-Economics-Program Division of the ''Institut Francais du Petrole''. The goal was the short-term (12 months) forecasting of the demand with regard to the four leading petroleum products in France - gas oil (GO), automotive (CA), home heating oil (FOD) and heavy fuel oil (FL). It was decided to test an original method (1) and to compare it with the widely used Box and Jenkins method (2), which gives good results for the GO and CA series but which proves disappointing for the FOD and FL series. This study is in two parts: (1) the first part describes the original method by breaking it down into trends and seasonality, with the model being additive or multiplicative. We improved its performances by using the theory of the Weiner filter; (2) the second part concerns Box an Jenkins modeling. This model was used on the unprocessed series and then on the series corrected for the influence of working days with the help of the ''Census-X11'' deseasonalization program. For each method, the principal phases are described for the modeling of gas oil on the French domestic market. For the other products, only the principal results are given, i.e. structure of the model retained, matching with reality, reliability of forecasts. (authors). 5 refs., 5 figs., 9 tabs

  14. Simplified fuel cell system model identification

    Energy Technology Data Exchange (ETDEWEB)

    Caux, S.; Fadel, M. [Laboratoire d' Electrotechnique et d' Electronique Industrielle, Toulouse (France); Hankache, W. [Laboratoire d' Electrotechnique et d' Electronique Industrielle, Toulouse (France)]|[Laboratoire de recherche en Electronique, Electrotechnique et Systemes, Belfort (France); Hissel, D. [Laboratoire de recherche en Electronique, Electrotechnique et Systemes, Belfort (France)

    2006-07-01

    This paper discussed a simplified physical fuel cell model used to study fuel cell and supercap energy applications for vehicles. Anode, cathode, membrane, and electrode elements of the cell were modelled. A quasi-static Amphlett model was used to predict voltage responses of the fuel cell as a function of the current, temperature, and partial pressures of the reactive gases. The potential of each cell was multiplied by the number of cells in order to model a fuel cell stack. The model was used to describe the main phenomena associated with current voltage behaviour. Data were then compared with data from laboratory tests conducted on a 20 cell stack subjected to a current and time profile developed using speed data from a vehicle operating in an urban environment. The validated model was used to develop iterative optimization algorithms for an energy management strategy that linked 3 voltage sources with fuel cell parameters. It was concluded that classic state and dynamic measurements using a simple least square algorithm can be used to identify the most important parameters for optimal fuel cell operation. 9 refs., 1 tab., 6 figs.

  15. Cell culture media impact on drug product solution stability.

    Science.gov (United States)

    Purdie, Jennifer L; Kowle, Ronald L; Langland, Amie L; Patel, Chetan N; Ouyang, Anli; Olson, Donald J

    2016-07-08

    To enable subcutaneous administration of monoclonal antibodies, drug product solutions are often needed at high concentrations. A significant risk associated with high drug product concentrations is an increase in aggregate level over the shelf-life dating period. While much work has been done to understand the impact of drug product formulation on aggregation, there is limited understanding of the link between cell culture process conditions and soluble aggregate growth in drug product. During cell culture process development, soluble aggregates are often measured at harvest using cell-free material purified by Protein A chromatography. In the work reported here, cell culture media components were evaluated with respect to their impact on aggregate levels in high concentration solution drug product during accelerated stability studies. Two components, cysteine and ferric ammonium citrate, were found to impact aggregate growth rates in our current media (version 1) leading to the development of new chemically defined media and concentrated feed formulations. The new version of media and associated concentrated feeds (version 2) were evaluated across four cell lines producing recombinant IgG4 monoclonal antibodies and a bispecific antibody. In all four cell lines, the version 2 media reduced aggregate growth over the course of a 12 week accelerated stability study compared with the version 1 media, although the degree to which aggregate growth decreased was cell line dependent. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:998-1008, 2016. © 2016 American Institute of Chemical Engineers.

  16. Recombinant protein production from stable mammalian cell lines and pools.

    Science.gov (United States)

    Hacker, David L; Balasubramanian, Sowmya

    2016-06-01

    We highlight recent developments for the production of recombinant proteins from suspension-adapted mammalian cell lines. We discuss the generation of stable cell lines using transposons and lentivirus vectors (non-targeted transgene integration) and site-specific recombinases (targeted transgene integration). Each of these methods results in the generation of cell lines with protein yields that are generally superior to those achievable through classical plasmid transfection that depends on the integration of the transfected DNA by non-homologous DNA end-joining. This is the main reason why these techniques can also be used for the generation of stable cell pools, heterogenous populations of recombinant cells generated by gene delivery and genetic selection without resorting to single cell cloning. This allows the time line from gene transfer to protein production to be reduced. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Large Scale Production of Stem Cells and Their Derivatives

    Science.gov (United States)

    Zweigerdt, Robert

    Stem cells have been envisioned to become an unlimited cell source for regenerative medicine. Notably, the interest in stem cells lies beyond direct therapeutic applications. They might also provide a previously unavailable source of valuable human cell types for screening platforms, which might facilitate the development of more efficient and safer drugs. The heterogeneity of stem cell types as well as the numerous areas of application suggests that differential processes are mandatory for their in vitro culture. Many of the envisioned applications would require the production of a high number of stem cells and their derivatives in scalable, well-defined and potentially clinical compliant manner under current good manufacturing practice (cGMP). In this review we provide an overview on recent strategies to develop bioprocesses for the expansion, differentiation and enrichment of stem cells and their progenies, presenting examples for adult and embryonic stem cells alike.

  18. Fuel Production from Seawater and Fuel Cells Using Seawater.

    Science.gov (United States)

    Fukuzumi, Shunichi; Lee, Yong-Min; Nam, Wonwoo

    2017-11-23

    Seawater is the most abundant resource on our planet and fuel production from seawater has the notable advantage that it would not compete with growing demands for pure water. This Review focuses on the production of fuels from seawater and their direct use in fuel cells. Electrolysis of seawater under appropriate conditions affords hydrogen and dioxygen with 100 % faradaic efficiency without oxidation of chloride. Photoelectrocatalytic production of hydrogen from seawater provides a promising way to produce hydrogen with low cost and high efficiency. Microbial solar cells (MSCs) that use biofilms produced in seawater can generate electricity from sunlight without additional fuel because the products of photosynthesis can be utilized as electrode reactants, whereas the electrode products can be utilized as photosynthetic reactants. Another important source for hydrogen is hydrogen sulfide, which is abundantly found in Black Sea deep water. Hydrogen produced by electrolysis of Black Sea deep water can also be used in hydrogen fuel cells. Production of a fuel and its direct use in a fuel cell has been made possible for the first time by a combination of photocatalytic production of hydrogen peroxide from seawater and dioxygen in the air and its direct use in one-compartment hydrogen peroxide fuel cells to obtain electric power. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Host cells and methods for production of isobutanol

    Science.gov (United States)

    Anthony, Larry Cameron; He, Hongxian; Huang, Lixuan Lisa; Okeefe, Daniel P.; Kruckeberg, Arthur Leo; Li, Yougen; Maggio-Hall, Lori; McElvain, Jessica; Nelson, Mark J.; Patnaik, Ranjan; Rothman, Steven Cary

    2017-10-17

    Provided herein are recombinant yeast host cells and methods for their use for production of isobutanol. Yeast host cells provided comprise an isobutanol biosynthetic pathway and at least one of reduced or eliminated aldehyde dehydrogenase activity, reduced or eliminated acetolactate reductase activity; or a heterologous polynucleotide encoding a polypeptide having ketol-acid reductoisomerase activity.

  20. Methods for production of proteins in host cells

    Science.gov (United States)

    Donnelly, Mark; Joachimiak, Andrzej

    2004-01-13

    The present invention provides methods for the production of proteins, particularly toxic proteins, in host cells. The invention provides methods which use a fusion protein comprising a chaperonin binding domain in host cells induced or regulated to have increased levels of chaperonin which binds the chaperonin binding domain.

  1. Modelling collective cell migration of neural crest.

    Science.gov (United States)

    Szabó, András; Mayor, Roberto

    2016-10-01

    Collective cell migration has emerged in the recent decade as an important phenomenon in cell and developmental biology and can be defined as the coordinated and cooperative movement of groups of cells. Most studies concentrate on tightly connected epithelial tissues, even though collective migration does not require a constant physical contact. Movement of mesenchymal cells is more independent, making their emergent collective behaviour less intuitive and therefore lending importance to computational modelling. Here we focus on such modelling efforts that aim to understand the collective migration of neural crest cells, a mesenchymal embryonic population that migrates large distances as a group during early vertebrate development. By comparing different models of neural crest migration, we emphasize the similarity and complementary nature of these approaches and suggest a future direction for the field. The principles derived from neural crest modelling could aid understanding the collective migration of other mesenchymal cell types. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Human invariant NKT cell subsets differentially promote differentiation, antibody production, and T cell stimulation by B cells in vitro.

    OpenAIRE

    O'REILLY, VINCENT

    2013-01-01

    PUBLISHED Invariant NK T (iNKT) cells can provide help for B cell activation and Ab production. Because B cells are also capable of cytokine production, Ag presentation, and T cell activation, we hypothesized that iNKT cells will also influence these activities. Furthermore, subsets of iNKT cells based on CD4 and CD8 expression that have distinct functional activities may differentially affect B cell functions. We investigated the effects of coculturing expanded human CD4(+), CD8α(+), and ...

  3. Storage and production of hydrogen for fuel cell applications

    Science.gov (United States)

    Aiello, Rita

    The increased utilization of proton-exchange membrane (PEM) fuel cells as an alternative to internal combustion engines is expected to increase the demand for hydrogen, which is used as the energy source in these systems. The objective of this work is to develop and test new methods for the storage and production of hydrogen for fuel cells. Six ligand-stabilized hydrides were synthesized and tested as hydrogen storage media for use in portable fuel cells. These novel compounds are more stable than classical hydrides (e.g., NaBH4, LiAlH4) and react to release hydrogen less exothermically upon hydrolysis with water. Three of the compounds produced hydrogen in high yield (88 to 100 percent of the theoretical) and at significantly lower temperatures than those required for the hydrolysis of NaBH4 and LiAlH4. However, a large excess of water and acid were required to completely wet the hydride and keep the pH of the reaction medium neutral. The hydrolysis of the classical hydrides with steam can overcome these limitations. This reaction was studied in a flow reactor and the results indicate that classical hydrides can be hydrolyzed with steam in high yields at low temperatures (110 to 123°C) and in the absence of acid. Although excess steam was required, the pH of the condensed steam was neutral. Consequently, steam could be recycled back to the reactor. Production of hydrogen for large-scale transportation fuel cells is primarily achieved via the steam reforming, partial oxidation or autothermal reforming of natural gas or the steam reforming of methanol. However, in all of these processes CO is a by-product that must be subsequently removed because the Pt-based electrocatalyst used in the fuel cells is poisoned by its presence. The direct cracking of methane over a Ni/SiO2 catalyst can produce CO-free hydrogen. In addition to hydrogen, filamentous carbon is also produced. This material accumulates on the catalyst and eventually deactivates it. The Ni/SiO2 catalyst

  4. Optimized microbial cells for production of melatonin and other compounds

    DEFF Research Database (Denmark)

    2017-01-01

    Described herein are recombinant microbial host cells comprising biosynthetic pathways and their use in producing oxidation products and downstream products, e.g., melatonin and related compounds, as well as enzyme variants, nucleic acids, vectors and methods useful for preparing and using...

  5. Production of alkaline protease by Teredinobacter turnirae cells ...

    African Journals Online (AJOL)

    The conditions for immobilizing the new alkaline protease-producing bacteria strain Teredinobacter turnirae by entrapment in calcium alginate gel were investigated. The influence of alginate concentration (20, 25 and 30 g/l) and initial cell loading (ICL) on enzyme production were studied. The production of alkaline ...

  6. A roadmap for cost-of-goods planning to guide economic production of cell therapy products.

    Science.gov (United States)

    Lipsitz, Yonatan Y; Milligan, William D; Fitzpatrick, Ian; Stalmeijer, Evelien; Farid, Suzanne S; Tan, Kah Yong; Smith, David; Perry, Robert; Carmen, Jessica; Chen, Allen; Mooney, Charles; Fink, John

    2017-12-01

    Cell therapy products are frequently developed and produced without incorporating cost considerations into process development, contributing to prohibitively costly products. Herein we contextualize individual process development decisions within a broad framework for cost-efficient therapeutic manufacturing. This roadmap guides the analysis of cost of goods (COG) arising from tissue procurement, material acquisition, facility operation, production, and storage. We present the specific COG considerations related to each of these elements as identified through a 2013 International Society for Cellular Therapy COG survey, highlighting the differences between autologous and allogeneic products. Planning and accounting for COG at each step in the production process could reduce costs, allowing for more affordable market pricing to improve the long-term viability of the cell therapy product and facilitate broader patient access to novel and transformative cell therapies. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  7. The Bilinear Product Model of Hysteresis Phenomena

    Science.gov (United States)

    Kádár, György

    1989-01-01

    In ferromagnetic materials non-reversible magnetization processes are represented by rather complex hysteresis curves. The phenomenological description of such curves needs the use of multi-valued, yet unambiguous, deterministic functions. The history dependent calculation of consecutive Everett-integrals of the two-variable Preisach-function can account for the main features of hysteresis curves in uniaxial magnetic materials. The traditional Preisach model has recently been modified on the basis of population dynamics considerations, removing the non-real congruency property of the model. The Preisach-function was proposed to be a product of two factors of distinct physical significance: a magnetization dependent function taking into account the overall magnetization state of the body and a bilinear form of a single variable, magnetic field dependent, switching probability function. The most important statement of the bilinear product model is, that the switching process of individual particles is to be separated from the book-keeping procedure of their states. This empirical model of hysteresis can easily be extended to other irreversible physical processes, such as first order phase transitions.

  8. Research on Digital Product Modeling Key Technologies of Digital Manufacturing

    Institute of Scientific and Technical Information of China (English)

    DING Guoping; ZHOU Zude; HU Yefa; ZHAO Liang

    2006-01-01

    With the globalization and diversification of the market and the rapid development of Information Technology (IT) and Artificial Intelligence (AI), the digital revolution of manufacturing is coming. One of the key technologies in digital manufacturing is product digital modeling. This paper firstly analyzes the information and features of the product digital model during each stage in the product whole lifecycle, then researches on the three critical technologies of digital modeling in digital manufacturing-product modeling, standard for the exchange of product model data and digital product data management. And the potential signification of the product digital model during the process of digital manufacturing is concluded-product digital model integrates primary features of each stage during the product whole lifecycle based on graphic features, applies STEP as data exchange mechanism, and establishes PDM system to manage the large amount, complicated and dynamic product data to implement the product digital model data exchange, sharing and integration.

  9. Extinction models for cancer stem cell therapy

    Science.gov (United States)

    Sehl, Mary; Zhou, Hua; Sinsheimer, Janet S.; Lange, Kenneth L.

    2012-01-01

    Cells with stem cell-like properties are now viewed as initiating and sustaining many cancers. This suggests that cancer can be cured by driving these cancer stem cells to extinction. The problem with this strategy is that ordinary stem cells are apt to be killed in the process. This paper sets bounds on the killing differential (difference between death rates of cancer stem cells and normal stem cells) that must exist for the survival of an adequate number of normal stem cells. Our main tools are birth–death Markov chains in continuous time. In this framework, we investigate the extinction times of cancer stem cells and normal stem cells. Application of extreme value theory from mathematical statistics yields an accurate asymptotic distribution and corresponding moments for both extinction times. We compare these distributions for the two cell populations as a function of the killing rates. Perhaps a more telling comparison involves the number of normal stem cells NH at the extinction time of the cancer stem cells. Conditioning on the asymptotic time to extinction of the cancer stem cells allows us to calculate the asymptotic mean and variance of NH. The full distribution of NH can be retrieved by the finite Fourier transform and, in some parameter regimes, by an eigenfunction expansion. Finally, we discuss the impact of quiescence (the resting state) on stem cell dynamics. Quiescence can act as a sanctuary for cancer stem cells and imperils the proposed therapy. We approach the complication of quiescence via multitype branching process models and stochastic simulation. Improvements to the τ-leaping method of stochastic simulation make it a versatile tool in this context. We conclude that the proposed therapy must target quiescent cancer stem cells as well as actively dividing cancer stem cells. The current cancer models demonstrate the virtue of attacking the same quantitative questions from a variety of modeling, mathematical, and computational perspectives

  10. Specificity of Good Manufacturing Practice (GMP) for Biomedical Cell Products.

    Science.gov (United States)

    Tulina, M A; Pyatigorskaya, N V

    2018-03-01

    The article describes special aspects of Good Manufacturing Practice (GMP) for biomedical cell products (BMCP) that imply high standards of aseptics throughout the entire productio process, strict requirements to donors and to the procedure of biomaterial isolation, guaranty of tracing BMCP products, defining processing procedures which allow to identify BMCP as minimally manipulated; continuous quality control and automation of the control process at all stages of manufacturing, which will ensure product release simultaneously with completion of technological operations.

  11. Automation of cells of radiopharmaceuticals production

    International Nuclear Information System (INIS)

    Negrini, Aguinaldo Donizete

    2010-01-01

    The 67 Ga is an important radiopharmaceutical used to identify inflammatory processes in chronic illnesses, diagnosis by image of tumors in soft tissues and the possibility to evaluate the result for therapeutic intervention. In the present work a module of 67 Ga processing was developed with the objective to reduce the interventions in the hot cell, in order to avoid oxidation caused by metallic materials, and consuming in hoses of the peristaltic pumps, that release residues that blocked the valves used in the process. With materials such as: acrylic, PVC, PEEK e teflon and they are used vacuum as method (way) of fluid transferences instead of peristaltic pump in the majority of the procedures, with this improvements the system can make shorter the lengths of transference hoses, increasing the yield in the process with less interventions for maintenance and time exposure of the workers, guaranteeing the quality and reducing the time of the processing. using a mobile system for displacement of the processing module making in the cleanness and maintenance of the cell that works with radioactive material. Reducing the time of exposure dose of the workers in compliance with RDC-17 of ANVISA, which ruling the Good Manufacturing Practice Procedures. (author)

  12. Defective TFH Cell Function and Increased TFR Cells Contribute to Defective Antibody Production in Aging.

    Science.gov (United States)

    Sage, Peter T; Tan, Catherine L; Freeman, Gordon J; Haigis, Marcia; Sharpe, Arlene H

    2015-07-14

    Defective antibody production in aging is broadly attributed to immunosenescence. However, the precise immunological mechanisms remain unclear. Here, we demonstrate an increase in the ratio of inhibitory T follicular regulatory (TFR) cells to stimulatory T follicular helper (TFH) cells in aged mice. Aged TFH and TFR cells are phenotypically distinct from those in young mice, exhibiting increased programmed cell death protein-1 expression but decreased ICOS expression. Aged TFH cells exhibit defective antigen-specific responses, and programmed cell death protein-ligand 1 blockade can partially rescue TFH cell function. In contrast, young and aged TFR cells have similar suppressive capacity on a per-cell basis in vitro and in vivo. Together, these studies reveal mechanisms contributing to defective humoral immunity in aging: an increase in suppressive TFR cells combined with impaired function of aged TFH cells results in reduced T-cell-dependent antibody responses in aged mice. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  13. Production of solar photovoltaic cells on the Moon

    Science.gov (United States)

    Criswell, David R.; Ignatiev, Alex

    1991-01-01

    Solar energy is directly available on the sunward lunar surface. Most, if not all, the materials are available on the Moon to make silicon based solar photovoltaic cells. A few additional types are possible. There is a small but growing literature on production of lunar derived solar cells. This literature is reviewed. Topics explored include trade-offs of local production versus import of key materials, processing options, the scale and nature of production equipment, implications of storage requirements, and the end-uses of the energy. Directions for future research and demonstrations are indicated.

  14. Methods and practices to diversify cell-based products.

    Science.gov (United States)

    Vertès, Alain A

    2017-12-15

    Medicinal signaling cell (MSC)-based products represent emerging treatments in various therapeutic areas including cardiometabolic, inflammation, autoimmunity, orthopedics, wound healing and oncology. Exploring innovation beyond minimally manipulated plastic-adherent ex vivo expanded allogeneic MSCs enables product delineation. Product delineation is on the critical path to maximize clinical benefits and market access. An innovation framework is presented here along various innovation dimensions comprising composition-of-matter by means of positive cell surface markers, formulation varying for example the cell dose or the preservation mode and medium, manufacturing to adapt the secretome of MSCs to the condition of interest, the mode of delivery and corresponding delivery devices, as well as molecular engineering and biomarkers. The rationale of the innovation space thus described applies generally to all cell-based therapies.

  15. Tumorigenicity studies for human pluripotent stem cell-derived products.

    Science.gov (United States)

    Kuroda, Takuya; Yasuda, Satoshi; Sato, Yoji

    2013-01-01

    Human pluripotent stem cells (hPSCs), i.e. human embryonic stem cells and human induced pluripotent stem cells, are able to self-renew and differentiate into multiple cell types. Because of these abilities, numerous attempts have been made to utilize hPSCs in regenerative medicine/cell therapy. hPSCs are, however, also tumorigenic, that is, they can give rise to the progressive growth of tumor nodules in immunologically unresponsive animals. Therefore, assessing and managing the tumorigenicity of all final products is essential in order to prevent ectopic tissue formation, tumor development, and/or malignant transformation elicited by residual pluripotent stem cells after implantation. No detailed guideline for the tumorigenicity testing of hPSC-derived products has yet been issued for regenerative medicine/cell therapy, despite the urgent necessity. Here, we describe the current situations and issues related to the tumorigenicity testing of hPSC-derived products and we review the advantages and disadvantages of several types of tumorigenicity-associated tests. We also refer to important considerations in the execution and design of specific studies to monitor the tumorigenicity of hPSC-derived products.

  16. High-Volume Production of Lightweight Multijunction Solar Cells

    Science.gov (United States)

    Youtsey, Christopher

    2015-01-01

    MicroLink Devices, Inc., has transitioned its 6-inch epitaxial lift-off (ELO) solar cell fabrication process into a manufacturing platform capable of sustaining large-volume production. This Phase II project improves the ELO process by reducing cycle time and increasing the yield of large-area devices. In addition, all critical device fabrication processes have transitioned to 6-inch production tool sets designed for volume production. An emphasis on automated cassette-to-cassette and batch processes minimizes operator dependence and cell performance variability. MicroLink Devices established a pilot production line capable of at least 1,500 6-inch wafers per month at greater than 80 percent yield. The company also increased the yield and manufacturability of the 6-inch reclaim process, which is crucial to reducing the cost of the cells.

  17. [Product safety analysis of somatic cell cloned bovine].

    Science.gov (United States)

    Hua, Song; Lan, Jie; Song, Yongli; Lu, Chenglong; Zhang, Yong

    2010-05-01

    Somatic cell cloning (nuclear transfer) is a technique through which the nucleus (DNA) of a somatic cell is transferred into an enucleated oocyte for the generation of a new individual, genetically identical to the somatic cell donor. It could be applied for the enhancement of reproduction rate and the improvement of food products involving quality, yield and nutrition. In recent years, the United States, Japan and Europe as well as other countries announced that meat and milk products made from cloned cattle are safe for human consumption. Yet, cloned animals are faced with a wide range of health problems, with a high death rate and a high incidence of disease. The precise causal mechanisms for the low efficiency of cloning remain unclear. Is it safe that any products from cloned animals were allowed into the food supply? This review focuses on the security of meat, milk and products from cloned cattle based on the available data.

  18. Microbial reverse-electrodialysis chemical-production cell for acid and alkali production

    KAUST Repository

    Zhu, Xiuping; Hatzell, Marta C.; Cusick, Roland D.; Logan, Bruce E.

    2013-01-01

    A new type of bioelectrochemical system, called a microbial reverse-electrodialysis chemical-production cell (MRCC), was developed to produce acid and alkali using energy derived from organic matter (acetate) and salinity gradients (NaCl solutions

  19. Models of black hole production at LHC

    International Nuclear Information System (INIS)

    Klippert, R.; Salinas, C. J. Solano

    2002-01-01

    The purpose of this paper is to discuss about the different models for black hole production at the future Large Hadron Collider. In traditional scenarios the Planck scale is fundamental, and the weak scale is derived from it via some dynamical mechanism. Recently, several authors are exploring an alternative viewpoint where the weak scale is the fundamental scale of nature and the 4-dimensional Planck scale is to be derived from that. These scenarios include large or warped extra dimensions, propagation of matter and gauge degrees of freedom on brane worlds, and a fundamental Planck scale of O(TeV). If the scale of quantum gravity is near TeV we will have a copious production of mini black holes at the Large Hadron Collider and Cosmic rays interactions in the atmosphere. We discussed as well other line of semi-classical models from analog gravity in nonlinear electrodynamics that can be tested as well at LHC. The possible consequences of these models for high energy experimental physics are discussed

  20. The economic production lot size model with several production rates

    DEFF Research Database (Denmark)

    Larsen, Christian

    should be chosen in the interval between the demand rate and the production rate, which minimize unit production costs, and should be used in an increasing order. Then, given the production rates, we derive closed form solutions for the optimal runtimes as well as the minimum average cost. Finally we...

  1. Human umbilical cord mesenchymal stem cells increase interleukin-9 production of CD4+ T cells

    Science.gov (United States)

    Yang, Zhou Xin; Chi, Ying; Ji, Yue Ru; Wang, You Wei; Zhang, Jing; Luo, Wei Feng; Li, Li Na; Hu, Cai Dong; Zhuo, Guang Sheng; Wang, Li Fang; Han, Zhi-Bo; Han, Zhong Chao

    2017-01-01

    Mesenchymal stem cells (MSC) are able to differentiate into cells of multiple lineage, and additionally act to modulate the immune response. Interleukin (IL)-9 is primarily produced by cluster of differentiation (CD)4+ T cells to regulate the immune response. The present study aimed to investigate the effect of human umbilical cord derived-MSC (UC-MSC) on IL-9 production of human CD4+ T cells. It was demonstrated that the addition of UC-MSC to the culture of CD4+ T cells significantly enhanced IL-9 production by CD4+ T cells. Transwell experiments suggested that UC-MSC promotion of IL-9 production by CD4+ T cells was dependent on cell-cell contact. Upregulated expression of CD106 was observed in UC-MSC co-cultured with CD4+ T cells, and the addition of a blocking antibody of CD106 significantly impaired the ability of UC-MSC to promote IL-9 production by CD4+ T cells. Therefore, the results of the present study demonstrated that UC-MSC promoted the generation of IL-9 producing cells, which may be mediated, in part by CD106. The findings may act to expand understanding and knowledge of the immune modulatory role of UC-MSC. PMID:29042945

  2. Dilepton production with the SMASH model

    International Nuclear Information System (INIS)

    Weil, Janus; Staudenmaier, Jan; Petersen, Hannah

    2016-01-01

    In this work the SMASH model is presented (“Simulating Many Accelerated Strongly-Interacting Hadrons”), a next-generation hadronic transport approach, which is designed to describe the non-equilibrium evolution of hadronic matter in heavy-ion collisions. We discuss first dilepton spectra obtained with SMASH in the few-GeV energy range of GSI/FAIR, where the dynamics of hadronic matter is dominated by the production and decay of various resonance states. In particular we show how electromagnetic transition form factors can emerge in a transport picture under the hypothesis of vector-meson dominance. (paper)

  3. H2 PRODUCTION AND FUEL CELLS.

    Energy Technology Data Exchange (ETDEWEB)

    WANG, X.; RODRIGUEZ, J.A.

    2006-06-30

    Oxide nanosystems play a key role as components of catalysts used for the production of H{sub 2} via the steam reforming or the partial oxidation of hydrocarbons, and for the water-gas shift reaction. The behavior seen for Cu-ceria and Au-ceria WGS catalysts indicates that the oxide is much more than a simple support. The special chemical properties of the oxide nanoparticles (defect rich, high mobility of oxygen) favor interactions with the reactants or other catalyst components. More in-situ characterization and mechanistic studies are necessary for the optimization of these nanocatalysts. The use of oxide nanomaterials for the fabrication of PEMFCs and SOFCs can lead to devices with a high practical impact. One objective is to build electrodes with low cost conducting oxide nanoarrays. The electron and oxygen-ion conducting capabilities of many oxides improve when going from the bulk to the nanoscale. Furthermore, one can get a more homogeneous surface morphology and an increase of the effective reaction area. Much more fundamental and practical research needs to be done in this area.

  4. Choosing the right platform for the right product: Sustainable production of chemicals in microbial cell factories

    DEFF Research Database (Denmark)

    Herrgard, Markus

    The Novo Nordisk Foundation Center for Biosustainability (CFB) is a new non-profit research center focused on sustainable production of biochemicals and therapeutic proteins using microbial and mammalian cell factories. The work at CFB is organized around an iterative loop where cell factories...

  5. Power-law approach to modeling biological systems. II. Application to ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    Voit, E O; Savageau, M A

    1982-01-01

    The use of the power-law formalism is illustrated by modeling yeast ethanol production in batch culture at high cell densities. Parameter values are estimated from experimental data. The results suggest that ethanol killing of viable cells and lysis of nonviable cells are major determinants of system behavior, whereas catabolism of ethanol and inhibition of cell growth by ethanol appear to be insignificant under these experimental conditions.

  6. Release of intracellular Calcium increase production of mitochondrial reactive oxygen species in renal distal epithelial cells

    DEFF Research Database (Denmark)

    Bjerregaard, Henning F.

    peroxide (H2O2) has traditionally been regarded as toxic by-products of aerobic metabolism. However, recent findings indicate that H2O2 act as a signalling molecule. The aim of the present study was to monitor, in real time, the rates of ROS generation in order to directly determine their production......Release of intracellular Calcium increase production of mitochondrial reactive oxygen species in renal distal epithelial cells. Henning F. Bjerregaard, Roskilde University, Department of Science, Systems and Models , 4000 Roskilde, Denmark. HFB@ RUC.DK Reactive oxygen species (ROS) like, hydrogen...... to G-protein stimulation of phospholipase C and release of inositol -3 phosphate. Cd (0.4 mM) treatment of A6 cells enhanced the ROS production after one minutes incubation. The production rate was constant for at least 10 to 20 min. Experiments showed that the Cd induced increase in ROS production...

  7. Retinal Cell Degeneration in Animal Models

    Directory of Open Access Journals (Sweden)

    Masayuki Niwa

    2016-01-01

    Full Text Available The aim of this review is to provide an overview of various retinal cell degeneration models in animal induced by chemicals (N-methyl-d-aspartate- and CoCl2-induced, autoimmune (experimental autoimmune encephalomyelitis, mechanical stress (optic nerve crush-induced, light-induced and ischemia (transient retinal ischemia-induced. The target regions, pathology and proposed mechanism of each model are described in a comparative fashion. Animal models of retinal cell degeneration provide insight into the underlying mechanisms of the disease, and will facilitate the development of novel effective therapeutic drugs to treat retinal cell damage.

  8. A speech production model including the nasal Cavity

    DEFF Research Database (Denmark)

    Olesen, Morten

    In order to obtain articulatory analysis of speech production the model is improved. the standard model, as used in LPC analysis, to a large extent only models the acoustic properties of speech signal as opposed to articulatory modelling of the speech production. In spite of this the LPC model...... is by far the most widely used model in speech technology....

  9. Simulation-based comparisons of four apparel cell production modes of one clothing production line

    Directory of Open Access Journals (Sweden)

    Guoqiang Pan

    2014-10-01

    Full Text Available Purpose: This research, by using the SIMIO simulation platform, provides a quantitative and comparative analysis of how the efficiency of four different cell production modes is affected. It is hoped that the outcomes will be of some help for garment factories to optimize their production lines. Design/methodology/approach: The SIMIO simulation platform was employed in the research and comparisons were made of the simulation test results about the four different production modes. Findings: The operation mode, number of operators, and number of buffer areas are key factors affecting the production line efficiency, and need to be reasonably set to achieve the highest efficiency. Originality/value: As most research literature so far is qualitative, this research provided a simulation-based quantitative analysis of the production efficiency under different cell production modes.

  10. Statistical modelling of fine red wine production

    Directory of Open Access Journals (Sweden)

    María Rosa Castro

    2010-01-01

    Full Text Available Producing wine is a very important economic activity in the province of San Juan in Argentina; it is therefore most important to predict production regarding the quantity of raw material needed. This work was aimed at obtaining a model relating kilograms of crushed grape to the litres of wine so produced. Such model will be used for predicting precise future values and confidence intervals for determined quantities of crushed grapes. Data from a vineyard in the province of San Juan was thus used in this work. The sampling coefficient of correlation was calculated and a dispersion diagram was then constructed; this indicated a li- neal relationship between the litres of wine obtained and the kilograms of crushed grape. Two lineal models were then adopted and variance analysis was carried out because the data came from normal populations having the same variance. The most appropriate model was obtained from this analysis; it was validated with experimental values, a good approach being obtained.

  11. On a poroviscoelastic model for cell crawling

    KAUST Repository

    Kimpton, L. S.; Whiteley, J. P.; Waters, S. L.; Oliver, J. M.

    2014-01-01

    -convected Maxwell model and demonstrate that even the simplest of two-phase, viscoelastic models displays features relevant to cell motility. We also show care must be exercised in choosing parameters for such models as a poor choice can lead to an ill-posed problem

  12. A hybrid mammalian cell cycle model

    Directory of Open Access Journals (Sweden)

    Vincent Noël

    2013-08-01

    Full Text Available Hybrid modeling provides an effective solution to cope with multiple time scales dynamics in systems biology. Among the applications of this method, one of the most important is the cell cycle regulation. The machinery of the cell cycle, leading to cell division and proliferation, combines slow growth, spatio-temporal re-organisation of the cell, and rapid changes of regulatory proteins concentrations induced by post-translational modifications. The advancement through the cell cycle comprises a well defined sequence of stages, separated by checkpoint transitions. The combination of continuous and discrete changes justifies hybrid modelling approaches to cell cycle dynamics. We present a piecewise-smooth version of a mammalian cell cycle model, obtained by hybridization from a smooth biochemical model. The approximate hybridization scheme, leading to simplified reaction rates and binary event location functions, is based on learning from a training set of trajectories of the smooth model. We discuss several learning strategies for the parameters of the hybrid model.

  13. Improving Labor Productivity and Labor Elasticity at Multiproduct Japanese Cuisine Restaurant Introducing Cell-Production System

    OpenAIRE

    Shimamura , Takeshi; Takenaka , Takeshi; Ohura , Syuichi

    2013-01-01

    Part III: Sustainable Services; International audience; This study examined improvement of labor productivity and elasticity of labor hour on sales of a multiproduct Japanese cuisine restaurant. Conventionally, multiproduct restaurant operations include a line production system in the kitchen. Japanese chefs are assumed to be low-skilled workers with staff members supported by someone. A cell production system is introduced into a Japanese Cuisine restaurant to improve it. Results show that t...

  14. Tumor necrosis factor alpha production in irradiated cells in vitro

    International Nuclear Information System (INIS)

    Koeteles, G.J.; Bognar, G.; Kubasova, T.

    1994-01-01

    Normal and tumor cell lines were used to investigate tumor necrosis factor (TNFα) production and its radiation sensitivity. The cells were irradiated with gamma rays using different doses from 0.25 Gy up to 5 Gy. The number of plated cells, changes of proliferation and TNFα production were determined during the following four post-irradiation days. For TNFα quantity measurement immuno-radiometric assay (IRMA) and enzyme amplified sensitivity assay (EASIA) was used. The results suggest that though gamma irradiation decreased cell proliferation in a dose dependent manner, the quantity produced in the post-irradiation period increased considerably in each irradiated sample. (N.T.) 3 refs.; 2 figs.; 1 tab

  15. On a poroviscoelastic model for cell crawling

    KAUST Repository

    Kimpton, L. S.

    2014-02-08

    In this paper a minimal, one-dimensional, two-phase, viscoelastic, reactive, flow model for a crawling cell is presented. Two-phase models are used with a variety of constitutive assumptions in the literature to model cell motility. We use an upper-convected Maxwell model and demonstrate that even the simplest of two-phase, viscoelastic models displays features relevant to cell motility. We also show care must be exercised in choosing parameters for such models as a poor choice can lead to an ill-posed problem. A stability analysis reveals that the initially stationary, spatially uniform strip of cytoplasm starts to crawl in response to a perturbation which breaks the symmetry of the network volume fraction or network stress. We also demonstrate numerically that there is a steady travelling-wave solution in which the crawling velocity has a bell-shaped dependence on adhesion strength, in agreement with biological observation.

  16. Biotechnological production of pharmaceuticals and biopharmaceuticals in plant cell and organ cultures.

    Science.gov (United States)

    Hidalgo, Diego; Sanchez, Raul; Lalaleo, Liliana; Bonfill, Mercedes; Corchete, Purificacion; Palazon, Javier

    2018-03-09

    Plant biofactories are biotechnological platforms based on plant cell and organ cultures used for the production of pharmaceuticals and biopharmaceuticals, although to date only a few of these systems have successfully been implemented at an industrial level. Metabolic engineering is possibly the most straightforward strategy to boost pharmaceutical production in plant biofactories, but social opposition to the use of GMOs means empirical approaches are still being used. Plant secondary metabolism involves thousands of different enzymes, some of which catalyze specific reactions, giving one product from a particular substrate, whereas others can yield multiple products from the same substrate. This trait opens plant cell biofactories to new applications, in which the natural metabolic machinery of plants can be harnessed for the bioconversion of phytochemicals or even the production of new bioactive compounds. Synthetic biological pipelines involving the bioconversion of natural substrates into products with a high market value may be established by the heterologous expression of target metabolic genes in model plants. To summarize the state of the art of plant biofactories and their applications for the pipeline production of cosme-, pharma- and biopharmaceuticals. In order to demonstrate the great potential of plant biofactories for multiple applications in the biotechnological production of pharmaceuticals and biopharmaceuticals, this review broadly covers the following: plant biofactories based on cell and hairy root cultures; secondary metabolite production; biotransformation reactions; metabolic engineering tools applied in plant biofactories; and biopharmaceutical production. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  17. A MODEL FOR POSTRADIATION STEM CELL KINETICS,

    Science.gov (United States)

    In polycythemic rats observed for 17 days postradiation (300 R, 250 KVP X-rays) it was noted that stem cell release diminished to 8 percent of the...correlate these findings with a kinetic model of erythropoiesis. It was suggested that the initial depression in stem cell release might be due to cellular

  18. Modeling collective cell migration in geometric confinement

    Science.gov (United States)

    Tarle, Victoria; Gauquelin, Estelle; Vedula, S. R. K.; D'Alessandro, Joseph; Lim, C. T.; Ladoux, Benoit; Gov, Nir S.

    2017-06-01

    Monolayer expansion has generated great interest as a model system to study collective cell migration. During such an expansion the culture front often develops ‘fingers’, which we have recently modeled using a proposed feedback between the curvature of the monolayer’s leading edge and the outward motility of the edge cells. We show that this model is able to explain the puzzling observed increase of collective cellular migration speed of a monolayer expanding into thin stripes, as well as describe the behavior within different confining geometries that were recently observed in experiments. These comparisons give support to the model and emphasize the role played by the edge cells and the edge shape during collective cell motion.

  19. Spatial Modeling Tools for Cell Biology

    National Research Council Canada - National Science Library

    Przekwas, Andrzej; Friend, Tom; Teixeira, Rodrigo; Chen, Z. J; Wilkerson, Patrick

    2006-01-01

    .... Scientific potentials and military relevance of computational biology and bioinformatics have inspired DARPA/IPTO's visionary BioSPICE project to develop computational framework and modeling tools for cell biology...

  20. Cytoview: Development of a cell modelling framework

    Indian Academy of Sciences (India)

    PRAKASH KUMAR

    is an important aspect of cell modelling. ... 1Supercomputer Education and Research Centreand 2Bioinformatics Centre, Indian Institute ... Important aspects in each panel are listed. ... subsumption relationship, in which the child term is a more.

  1. TIM-1 signaling in B cells regulates antibody production

    International Nuclear Information System (INIS)

    Ma, Juan; Usui, Yoshihiko; Takeda, Kazuyoshi; Harada, Norihiro; Yagita, Hideo; Okumura, Ko; Akiba, Hisaya

    2011-01-01

    Highlights: → TIM-1 is highly expressed on anti-IgM + anti-CD40-stimulated B cells. → Anti-TIM-1 mAb enhanced proliferation and Ig production on activated B cell in vitro. → TIM-1 signaling regulates Ab production by response to TI-2 and TD antigens in vivo. -- Abstract: Members of the T cell Ig and mucin (TIM) family have recently been implicated in the control of T cell-mediated immune responses. In this study, we found TIM-1 expression on anti-IgM- or anti-CD40-stimulated splenic B cells, which was further up-regulated by the combination of anti-IgM and anti-CD40 Abs. On the other hand, TIM-1 ligand was constitutively expressed on B cells and inducible on anti-CD3 + anti-CD28-stimulated CD4 + T cells. In vitro stimulation of activated B cells by anti-TIM-1 mAb enhanced proliferation and expression of a plasma cell marker syndecan-1 (CD138). We further examined the effect of TIM-1 signaling on antibody production in vitro and in vivo. Higher levels of IgG2b and IgG3 secretion were detected in the culture supernatants of the anti-TIM-1-stimulated B cells as compared with the control IgG-stimulated B cells. When immunized with T-independent antigen TNP-Ficoll, TNP-specific IgG1, IgG2b, and IgG3 Abs were slightly increased in the anti-TIM-1-treated mice. When immunized with T-dependent antigen OVA, serum levels of OVA-specific IgG2b, IgG3, and IgE Abs were significantly increased in the anti-TIM-1-treated mice as compared with the control IgG-treated mice. These results suggest that TIM-1 signaling in B cells augments antibody production by enhancing B cell proliferation and differentiation.

  2. TIM-1 signaling in B cells regulates antibody production

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Juan [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Usui, Yoshihiko [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Department of Ophthalmology, Tokyo Medical University, 6-7-1 Nishi-shinjuku-ku, Tokyo 160-0023 (Japan); Takeda, Kazuyoshi [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Harada, Norihiro [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Department of Respiratory Medicine, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Research Institute for Diseases of Old Ages, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Yagita, Hideo; Okumura, Ko [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan); Akiba, Hisaya, E-mail: hisaya@juntendo.ac.jp [Department of Immunology, Juntendo University, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421 (Japan)

    2011-03-11

    Highlights: {yields} TIM-1 is highly expressed on anti-IgM + anti-CD40-stimulated B cells. {yields} Anti-TIM-1 mAb enhanced proliferation and Ig production on activated B cell in vitro. {yields} TIM-1 signaling regulates Ab production by response to TI-2 and TD antigens in vivo. -- Abstract: Members of the T cell Ig and mucin (TIM) family have recently been implicated in the control of T cell-mediated immune responses. In this study, we found TIM-1 expression on anti-IgM- or anti-CD40-stimulated splenic B cells, which was further up-regulated by the combination of anti-IgM and anti-CD40 Abs. On the other hand, TIM-1 ligand was constitutively expressed on B cells and inducible on anti-CD3{sup +} anti-CD28-stimulated CD4{sup +} T cells. In vitro stimulation of activated B cells by anti-TIM-1 mAb enhanced proliferation and expression of a plasma cell marker syndecan-1 (CD138). We further examined the effect of TIM-1 signaling on antibody production in vitro and in vivo. Higher levels of IgG2b and IgG3 secretion were detected in the culture supernatants of the anti-TIM-1-stimulated B cells as compared with the control IgG-stimulated B cells. When immunized with T-independent antigen TNP-Ficoll, TNP-specific IgG1, IgG2b, and IgG3 Abs were slightly increased in the anti-TIM-1-treated mice. When immunized with T-dependent antigen OVA, serum levels of OVA-specific IgG2b, IgG3, and IgE Abs were significantly increased in the anti-TIM-1-treated mice as compared with the control IgG-treated mice. These results suggest that TIM-1 signaling in B cells augments antibody production by enhancing B cell proliferation and differentiation.

  3. Controlling cell volume for efficient PHB production by Halomonas.

    Science.gov (United States)

    Jiang, Xiao-Ran; Yao, Zhi-Hao; Chen, Guo-Qiang

    2017-11-01

    Bacterial morphology is decided by cytoskeleton protein MreB and cell division protein FtsZ encoded by essential genes mreB and ftsZ, respectively. Inactivating mreB and ftsZ lead to increasing cell sizes and cell lengths, respectively, yet seriously reduce cell growth ability. Here we develop a temperature-responsible plasmid expression system for compensated expression of relevant gene(s) in mreB or ftsZ disrupted recombinants H. campaniensis LS21, allowing mreB or ftsZ disrupted recombinants to grow normally at 30°C in a bioreactor for 12h so that a certain cell density can be reached, followed by 36h cell size expansions or cell shape elongations at elevated 37°C at which the mreB and ftsZ encoded plasmid pTKmf failed to replicate in the recombinants and thus lost themselves. Finally, 80% PHB yield increase was achieved via controllable morphology manipulated H. campaniensis LS21. It is concluded that controllable expanding cell volumes (widths or lengths) provides more spaces for accumulating more inclusion body polyhydroxybutyrate (PHB) and the resulting cell gravity precipitation benefits the final separation of cells and product during downstream. Copyright © 2017 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  4. LG Solid Oxide Fuel Cell (SOFC) Model Development

    Energy Technology Data Exchange (ETDEWEB)

    Haberman, Ben [LG Fuel Cell Systems Inc., North Canton, OH (United States); Martinez-Baca, Carlos [LG Fuel Cell Systems Inc., North Canton, OH (United States); Rush, Greg [LG Fuel Cell Systems Inc., North Canton, OH (United States)

    2013-05-31

    This report presents a summary of the work performed by LG Fuel Cell Systems Inc. during the project LG Solid Oxide Fuel Cell (SOFC) Model Development (DOE Award Number: DE-FE0000773) which commenced on October 1, 2009 and was completed on March 31, 2013. The aim of this project is for LG Fuel Cell Systems Inc. (formerly known as Rolls-Royce Fuel Cell Systems (US) Inc.) (LGFCS) to develop a multi-physics solid oxide fuel cell (SOFC) computer code (MPC) for performance calculations of the LGFCS fuel cell structure to support fuel cell product design and development. A summary of the initial stages of the project is provided which describes the MPC requirements that were developed and the selection of a candidate code, STAR-CCM+ (CD-adapco). This is followed by a detailed description of the subsequent work program including code enhancement and model verification and validation activities. Details of the code enhancements that were implemented to facilitate MPC SOFC simulations are provided along with a description of the models that were built using the MPC and validated against experimental data. The modeling work described in this report represents a level of calculation detail that has not been previously available within LGFCS.

  5. Models for high cell density bioreactors must consider biomass volume fraction: Cell recycle example.

    Science.gov (United States)

    Monbouquette, H G

    1987-06-01

    Intrinsic models, which take into account biomass volume fraction, must be formulated for adequate simulation of high-biomass-density fermentations with cell recycle. Through comparison of corresponding intrinsic and non-intrinsic models in dimensionless form, constraints for non-intrinsic model usage in terms of biokinetic and fermenter operating parameters can be identified a priori. Analysis of a simple product-inhibition model indicates that the non-intrinsic approach is suitable only when the attainable biomass volume fraction in the fermentation broth is less than about 0.10. Inappropriate application of a non-intrinsic model can lead to gross errors in calculated substrate and product concentrations, substrate conversion, and volumetric productivity.

  6. Models for high cell density bioreactors must consider biomass volume fraction: cell recycle example

    Energy Technology Data Exchange (ETDEWEB)

    Monbouquette, H.G.

    1987-06-01

    Intrinsic models, which take into account biomass volume fraction, must be formulated for adequate simulation of high-biomass-density fermentations with cell recycle. Through comparison of corresponding intrinsic and non-intrinsic models in dimensionless form, constraints for non-intrinsic model usage in terms of biokinetic and fermenter operating parameters can be identified a priori. Analysis of a simple product-inhibition model indicates that the non-intrinsic approach is suitable only when the attainable biomass volume fraction in the fermentation broth is less than about 0.10. Inappropriate application of a non-intrinsic model can lead to gross errors in calculated substrate and product concentrations, substrate conversion, and volumetric productivity. (Refs. 14).

  7. Macrophage-mediated gliadin degradation and concomitant IL-27 production drive IL-10- and IFN-γ-secreting Tr1-like-cell differentiation in a murine model for gluten tolerance.

    Science.gov (United States)

    van Leeuwen, M A; Costes, L M M; van Berkel, L A; Simons-Oosterhuis, Y; du Pré, M F; Kozijn, A E; Raatgeep, H C; Lindenbergh-Kortleve, D J; van Rooijen, N; Koning, F; Samsom, J N

    2017-05-01

    Celiac disease is caused by inflammatory T-cell responses against the insoluble dietary protein gliadin. We have shown that, in humanized mice, oral tolerance to deamidated chymotrypsin-digested gliadin (CT-TG2-gliadin) is driven by tolerogenic interferon (IFN)-γ- and interleukin (IL)-10-secreting type 1 regulatory T-like cells (Tr1-like cells) generated in the spleen but not in the mesenteric lymph nodes. We aimed to uncover the mechanisms underlying gliadin-specific Tr1-like-cell differentiation and hypothesized that proteolytic gliadin degradation by splenic macrophages is a decisive step in this process. In vivo depletion of macrophages caused reduced differentiation of splenic IFN-γ- and IL-10-producing Tr1-like cells after CT-TG2-gliadin but not gliadin peptide feed. Splenic macrophages, rather than dendritic cells, constitutively expressed increased mRNA levels of the endopeptidase Cathepsin D; macrophage depletion significantly reduced splenic Cathepsin D expression in vivo and Cathepsin D efficiently degraded recombinant γ-gliadin in vitro. In response to CT-TG2-gliadin uptake, macrophages enhanced the expression of Il27p28, a cytokine that favored differentiation of gliadin-specific Tr1-like cells in vitro, and was previously reported to increase Cathepsin D activity. Conversely, IL-27 neutralization in vivo inhibited splenic IFN-γ- and IL-10-secreting Tr1-like-cell differentiation after CT-TG2-gliadin feed. Our data infer that endopeptidase mediated gliadin degradation by macrophages and concomitant IL-27 production drive differentiation of splenic gliadin-specific Tr1-like cells.

  8. Robo signaling regulates the production of cranial neural crest cells.

    Science.gov (United States)

    Li, Yan; Zhang, Xiao-Tan; Wang, Xiao-Yu; Wang, Guang; Chuai, Manli; Münsterberg, Andrea; Yang, Xuesong

    2017-12-01

    Slit/Robo signaling plays an important role in the guidance of developing neurons in developing embryos. However, it remains obscure whether and how Slit/Robo signaling is involved in the production of cranial neural crest cells. In this study, we examined Robo1 deficient mice to reveal developmental defects of mouse cranial frontal and parietal bones, which are derivatives of cranial neural crest cells. Therefore, we determined the production of HNK1 + cranial neural crest cells in early chick embryo development after knock-down (KD) of Robo1 expression. Detection of markers for pre-migratory and migratory neural crest cells, PAX7 and AP-2α, showed that production of both was affected by Robo1 KD. In addition, we found that the transcription factor slug is responsible for the aberrant delamination/EMT of cranial neural crest cells induced by Robo1 KD, which also led to elevated expression of E- and N-Cadherin. N-Cadherin expression was enhanced when blocking FGF signaling with dominant-negative FGFR1 in half of the neural tube. Taken together, we show that Slit/Robo signaling influences the delamination/EMT of cranial neural crest cells, which is required for cranial bone development. Copyright © 2017. Published by Elsevier Inc.

  9. Apparatus of hot cell for iodine-123 production

    International Nuclear Information System (INIS)

    Almeida, G.L. de; Rautenberg, F.A.; Souza, A.S.F. de.

    1986-01-01

    The hot cell installation at IEN cyclotron (Brazilian-CNEN) for sup(123)I production is presented. Several devices, such as, tube furnace coupling system, tube furnace driving system, sup(123)I target transfer system, product extraction system, furnace control system, and effluent systems, were constructed and modified for implanting process engineering. The requirements of safety engineering for operation process were based on ALARA concept. (M.C.K.)

  10. Proposal for product development model focused on ce certification methodology

    Directory of Open Access Journals (Sweden)

    Nathalia Marcia Goulart Pinheiro

    2015-09-01

    Full Text Available This paper presents a critical analysis comparing 21 product development models in order to identify whether these structures meet the demands Product Certification of the European Community (CE. Furthermore, it presents a product development model, comprising the steps in the models analyzed, including improvements in activities for referred product certification. The proposed improvements are justified by the growing quest for the internationalization of products and processes within companies.

  11. Engineering microbial cell factories for the production of plant natural products: from design principles to industrial-scale production.

    Science.gov (United States)

    Liu, Xiaonan; Ding, Wentao; Jiang, Huifeng

    2017-07-19

    Plant natural products (PNPs) are widely used as pharmaceuticals, nutraceuticals, seasonings, pigments, etc., with a huge commercial value on the global market. However, most of these PNPs are still being extracted from plants. A resource-conserving and environment-friendly synthesis route for PNPs that utilizes microbial cell factories has attracted increasing attention since the 1940s. However, at the present only a handful of PNPs are being produced by microbial cell factories at an industrial scale, and there are still many challenges in their large-scale application. One of the challenges is that most biosynthetic pathways of PNPs are still unknown, which largely limits the number of candidate PNPs for heterologous microbial production. Another challenge is that the metabolic fluxes toward the target products in microbial hosts are often hindered by poor precursor supply, low catalytic activity of enzymes and obstructed product transport. Consequently, despite intensive studies on the metabolic engineering of microbial hosts, the fermentation costs of most heterologously produced PNPs are still too high for industrial-scale production. In this paper, we review several aspects of PNP production in microbial cell factories, including important design principles and recent progress in pathway mining and metabolic engineering. In addition, implemented cases of industrial-scale production of PNPs in microbial cell factories are also highlighted.

  12. The Structured Intuitive Model for Product Line Economics (SIMPLE)

    National Research Council Canada - National Science Library

    Clements, Paul C; McGregor, John D; Cohen, Sholom G

    2005-01-01

    .... This report presents the Structured Intuitive Model of Product Line Economics (SIMPLE), a general-purpose business model that supports the estimation of the costs and benefits in a product line development organization...

  13. Information Sharing In Shipbuilding based on the Product State Model

    DEFF Research Database (Denmark)

    Larsen, Michael Holm

    1999-01-01

    The paper provides a review of product modelling technologies and the overall architecture for the Product State Model (PSM) environment as a basis for how dynamically updated product data can improve control of production activities. Especially, the paper focuses on the circumstances prevailing...

  14. The Alpha Stem Cell Clinic: a model for evaluating and delivering stem cell-based therapies.

    Science.gov (United States)

    Trounson, Alan; DeWitt, Natalie D; Feigal, Ellen G

    2012-01-01

    Cellular therapies require the careful preparation, expansion, characterization, and delivery of cells in a clinical environment. There are major challenges associated with the delivery of cell therapies and high costs that will limit the companies available to fully evaluate their merit in clinical trials, and will handicap their application at the present financial environment. Cells will be manufactured in good manufacturing practice or near-equivalent facilities with prerequisite safety practices in place, and cell delivery systems will be specialized and require well-trained medical and nursing staff, technicians or nurses trained to handle cells once delivered, patient counselors, as well as statisticians and database managers who will oversee the monitoring of patients in relatively long-term follow-up studies. The model proposed for Alpha Stem Cell Clinics will initially use the capacities and infrastructure that exist in the most advanced tertiary medical clinics for delivery of established bone marrow stem cell therapies. As the research evolves, they will incorporate improved procedures and cell preparations. This model enables commercialization of medical devices, reagents, and other products required for cell therapies. A carefully constructed cell therapy clinical infrastructure with the requisite scientific, technical, and medical expertise and operational efficiencies will have the capabilities to address three fundamental and critical functions: 1) fostering clinical trials; 2) evaluating and establishing safe and effective therapies, and 3) developing and maintaining the delivery of therapies approved by the Food and Drug Administration, or other regulatory agencies.

  15. Billion-scale production of hepatocyte-like cells from human induced pluripotent stem cells.

    Science.gov (United States)

    Yamashita, Tomoki; Takayama, Kazuo; Sakurai, Fuminori; Mizuguchi, Hiroyuki

    2018-02-19

    Human induced pluripotent stem (iPS) cell-derived hepatocyte-like cells are expected to be utilized in drug screening and regenerative medicine. However, hepatocyte-like cells have not been fully used in such applications because it is difficult to produce such cells on a large scale. In this study, we tried to establish a method to mass produce hepatocyte-like cells using a three-dimensional (3D) cell culture bioreactor called the Rotary Cell Culture System (RCCS). RCCS enabled us to obtain homogenous hepatocyte-like cells on a billion scale (>10 9  cells). The gene expression levels of some hepatocyte markers (alpha-1 antitrypsin, cytochrome (CYP) 1A2, CYP2D6, and hepatocyte nuclear factor 4alpha) were higher in 3D-cultured hepatocyte-like cells than in 2D-cultured hepatocyte-like cells. This result suggests that RCCS could provide more suitable conditions for hepatocyte maturation than the conventional 2D cell culture conditions. In addition, more than 90% of hepatocyte-like cells were positive for albumin and could uptake low-density lipoprotein in the culture medium. We succeeded in the large-scale production of homogenous and functional hepatocyte-like cells from human iPS cells. This technology will be useful in drug screening and regenerative medicine, which require enormous numbers of hepatocyte-like cells. Copyright © 2018 Elsevier Inc. All rights reserved.

  16. Modulation of immunoglobulin production by invariant Vα19-Jα33 TCR-bearing cells.

    Directory of Open Access Journals (Sweden)

    Michio Shimamura

    Full Text Available We have previously shown that invariant Vα19-Jα33 TCR(+ (Vα19i T cells suppress the disease progress in some models for organ specific autoimmune diseases and type IV allergy that deteriorate along with decline to excess in Th1- or Th17- immunity. In this study, we examined the effects of over-generation of Vα19i T cells on the Th2-controlled immunoglobulin isotype production in the models for type I allergy. IgE production by invariant Vα19-Jα33 TCR transgenic (Tg mice was suppressed compared with that by non-Tg controls following administration with goat anti-mouse IgD antiserum or OVA, while IgG2a production was not influenced by the introduction of the transgene into the recipients. IgE production by wild type mice was similarly reduced when they were subjected to adoptive transfer with invariant Vα19-Jα33 TCR Tg(+ but not Tg(- cells prior to immunization. Furthermore, the suppression of IgE production by these recipients was enhanced when they were previously administered with a Vα19i T cell activator, one of the modified α-mannosyl ceramides. In summary, it is suggested that Vα19i T cells have potential to participate in the homeostasis of immunity and that they suppress disease progression resulting from not only Th1- but also Th2- immunity excess.

  17. Kanban simulation model for production process optimization

    Directory of Open Access Journals (Sweden)

    Golchev Riste

    2015-01-01

    Full Text Available A long time has passed since the KANBAN system has been established as an efficient method for coping with the excessive inventory. Still, the possibilities for its improvement through its integration with other different approaches should be investigated further. The basic research challenge of this paper is to present benefits of KANBAN implementation supported with Discrete Event Simulation (DES. In that direction, at the beginning, the basics of KANBAN system are presented with emphasis on the information and material flow, together with a methodology for implementation of KANBAN system. Certain analysis on combining the simulation with this methodology is presented. The paper is concluded with a practical example which shows that through understanding the philosophy of the implementation methodology of KANBAN system and the simulation methodology, a simulation model can be created which can serve as a basis for a variety of experiments that can be conducted within a short period of time, resulting with production process optimization.

  18. Mathematical modeling of solid oxide fuel cells

    Science.gov (United States)

    Lu, Cheng-Yi; Maloney, Thomas M.

    1988-01-01

    Development of predictive techniques, with regard to cell behavior, under various operating conditions is needed to improve cell performance, increase energy density, reduce manufacturing cost, and to broaden utilization of various fuels. Such technology would be especially beneficial for the solid oxide fuel cells (SOFC) at it early demonstration stage. The development of computer models to calculate the temperature, CD, reactant distributions in the tubular and monolithic SOFCs. Results indicate that problems of nonuniform heat generation and fuel gas depletion in the tubular cell module, and of size limitions in the monolithic (MOD 0) design may be encountered during FC operation.

  19. Use of a small molecule cell cycle inhibitor to control cell growth and improve specific productivity and product quality of recombinant proteins in CHO cell cultures.

    Science.gov (United States)

    Du, Zhimei; Treiber, David; McCarter, John D; Fomina-Yadlin, Dina; Saleem, Ramsey A; McCoy, Rebecca E; Zhang, Yuling; Tharmalingam, Tharmala; Leith, Matthew; Follstad, Brian D; Dell, Brad; Grisim, Brent; Zupke, Craig; Heath, Carole; Morris, Arvia E; Reddy, Pranhitha

    2015-01-01

    The continued need to improve therapeutic recombinant protein productivity has led to ongoing assessment of appropriate strategies in the biopharmaceutical industry to establish robust processes with optimized critical variables, that is, viable cell density (VCD) and specific productivity (product per cell, qP). Even though high VCD is a positive factor for titer, uncontrolled proliferation beyond a certain cell mass is also undesirable. To enable efficient process development to achieve consistent and predictable growth arrest while maintaining VCD, as well as improving qP, without negative impacts on product quality from clone to clone, we identified an approach that directly targets the cell cycle G1-checkpoint by selectively inhibiting the function of cyclin dependent kinases (CDK) 4/6 with a small molecule compound. Results from studies on multiple recombinant Chinese hamster ovary (CHO) cell lines demonstrate that the selective inhibitor can mediate a complete and sustained G0/G1 arrest without impacting G2/M phase. Cell proliferation is consistently and rapidly controlled in all recombinant cell lines at one concentration of this inhibitor throughout the production processes with specific productivities increased up to 110 pg/cell/day. Additionally, the product quality attributes of the mAb, with regard to high molecular weight (HMW) and glycan profile, are not negatively impacted. In fact, high mannose is decreased after treatment, which is in contrast to other established growth control methods such as reducing culture temperature. Microarray analysis showed major differences in expression of regulatory genes of the glycosylation and cell cycle signaling pathways between these different growth control methods. Overall, our observations showed that cell cycle arrest by directly targeting CDK4/6 using selective inhibitor compound can be utilized consistently and rapidly to optimize process parameters, such as cell growth, qP, and glycosylation profile in

  20. Ethanol production by immobilized cells with forced substrate supply

    Energy Technology Data Exchange (ETDEWEB)

    Mitani, Y.; Nishizawa, Y.; Nagai, S.

    1984-01-01

    Ethanol fermentation by a forced substrate supply into an immobilized cell layer was carried out to increase the ethanol production rate and to eliminate the diffusion dependency of substrate supply in an ordinary immobilized cell reaction. Saccharomyces cerevisiae IFO 2347 was immobilized in a mixture of k-carrageenan, locust bean gum, and celite (2: 0.5: 40 wt/vol %). A glucose minimal medium was fed into the immobilized cell layer (5 to 22 mm in thickness) at retention times between 0.6 and 2.8 h under pressure. The stable ethanol fermentation could be maintained for more than 3 weeks with an ethanol yield of 0.48 g ethanol/g glucose and ethanol productivity of 63 g.(l gel)/sup -1/.h/sup -1/ at a retention time of 1.5 h. The yeast cells were well distributed through the gel layer with a vertical gradient, and an average cell density was ca. 8.0 X 10/sup 9/ cells/ml gel, 4-fold higher than that of ordinary immobilized cells. A small filter press reactor was constructed to examine the applicability of ethanol fermentation with this forced substrate supply. The operation could be continued for a month at a retention time of 2 h yielding 96 g/l of ethanol from 200 g/l of glucose. 6 references, 5 figures, 3 tables.

  1. Durable solid oxide electrolysis cells for hydrogen production

    DEFF Research Database (Denmark)

    Sun, Xiufu; Chen, Ming; Hendriksen, Peter Vang

    2014-01-01

    production is required for promoting commercialization of the SOEC technology. In this work, we report a recent 4400 hours test of a state-of-the-art Ni-YSZ electrode supported SOEC cell. The cell consists of a Ni-YSZ (YSZ: yttria stabilized zirconia) support and active fuel electrode, an YSZ electrolyte...... that except for the first 250 hours fast initial degradation, for the rest of the testing period, the cell showed rather stable performance with an moderate degradation rate of around 25 mV/1000 h. The electrochemical impedance spectra show that both serial resistance and polarization resistance of the cell...... and changing of porosity inside the active layer. The degree of these microstructural changes becomes less and less severe along the hydrogen-steam flow path. The present test results show that this type of cell can be used for early demonstration electrolysis at 1A/cm2. Future work should be focus on reducing...

  2. Production of Polystyrene Open-celled Microcellular Foam in Batch Process by Super Critical CO2

    Directory of Open Access Journals (Sweden)

    M.S. Enayati

    2010-12-01

    Full Text Available Open-celled foams are capable to allow the passage of fluids through their structure, because of interconnections between the open cells or bubbles and therefore these structures can be used as a membrane and filter. In thiswork, we have studied the production of polystyrene open-celled microcellular foam by using CO2 as blowing agent. To achieve such structures, it is necessary to control the stages of growth in such a way that the cells would connect to each other through the pores without any coalescence. The required processing condition to achieve open-celled structures is predictable by a model theory of opened-cell. This model suggests that at least a 130 bar saturation pressure and foaming time between 9 and 58 s are required for this system. The temperature range has been selected for to be both higher than polymer glass transition temperature and facilitating the foaming process. Experimental results in the batch foaming process has verified the model quite well. The SEM and mercury porousimetry tests show the presence of pores between the cells with open-celled structure. Experimental results show that by increasing the saturation pressure and the foaming temperature, there is a drop in the time required for open-celled structure formation. A 130 bar saturation pressure, 150o C foaming temperature and 60 s foaming time, suggest the attainment of open-celled microcellular foam based on polystyrene/CO2 system in the batch process.

  3. Mathematical modeling of a thermovoltaic cell

    Science.gov (United States)

    White, Ralph E.; Kawanami, Makoto

    1992-01-01

    A new type of battery named 'Vaporvolt' cell is in the early stage of its development. A mathematical model of a CuO/Cu 'Vaporvolt' cell is presented that can be used to predict the potential and the transport behavior of the cell during discharge. A sensitivity analysis of the various transport and electrokinetic parameters indicates which parameters have the most influence on the predicted energy and power density of the 'Vaporvolt' cell. This information can be used to decide which parameters should be optimized or determined more accurately through further modeling or experimental studies. The optimal thicknesses of electrodes and separator, the concentration of the electrolyte, and the current density are determined by maximizing the power density. These parameter sensitivities and optimal design parameter values will help in the development of a better CuO/Cu 'Vaporvolt' cell.

  4. A Rapid Cell Expansion Process for Production of Engineered Autologous CAR-T Cell Therapies.

    Science.gov (United States)

    Lu, Tangying Lily; Pugach, Omar; Somerville, Robert; Rosenberg, Steven A; Kochenderfer, James N; Better, Marc; Feldman, Steven A

    2016-12-01

    The treatment of B-cell malignancies by adoptive cell transfer (ACT) of anti-CD19 chimeric antigen receptor T cells (CD19 CAR-T) has proven to be a highly successful therapeutic modality in several clinical trials. 1-6 The anti-CD19 CAR-T cell production method used to support initial trials relied on numerous manual, open process steps, human serum, and 10 days of cell culture to achieve a clinical dose. 7 This approach limited the ability to support large multicenter clinical trials, as well as scale up for commercial cell production. Therefore, studies were completed to streamline and optimize the original National Cancer Institute production process by removing human serum from the process in order to minimize the risk of viral contamination, moving process steps from an open system to functionally closed system operations in order to minimize the risk of microbial contamination, and standardizing additional process steps in order to maximize process consistency. This study reports a procedure for generating CD19 CAR-T cells in 6 days, using a functionally closed manufacturing process and defined, serum-free medium. This method is able to produce CD19 CAR-T cells that are phenotypically and functionally indistinguishable from cells produced for clinical trials by the previously described production process.

  5. CD154 costimulated ovine primary B cells, a cell culture system that supports productive infection by bovine leukemia virus.

    Science.gov (United States)

    Van den Broeke, A; Cleuter, Y; Beskorwayne, T; Kerkhofs, P; Szynal, M; Bagnis, C; Burny, A; Griebel, P

    2001-02-01

    Bovine leukemia virus (BLV) is closely associated with the development of B-cell leukemia and lymphoma in cattle. BLV infection has also been studied extensively in an in vivo ovine model that provides a unique system for studying B-cell leukemogenesis. There is no evidence that BLV can directly infect ovine B cells in vitro, and there are no direct data regarding the oncogenic potential of the viral Tax transactivator in B cells. Therefore, we developed ovine B-cell culture systems to study the interaction between BLV and its natural target, the B cell. In this study, we used murine CD154 (CD40 ligand) and gamma-chain-common cytokines to support the growth of B cells isolated from ovine lymphoid tissues. Integrated provirus, extrachromosomal forms, and viral transcripts were detected in BLV-exposed populations of immature, rapidly dividing surface immunoglobulin M-positive B cells from sheep ileal Peyer's patches and also in activated mature B cells isolated from blood. Conclusive evidence of direct B-cell infection by BLV was obtained through the use of cloned B cells derived from sheep jejunal Peyer's patches. Finally, inoculation of sheep with BLV-infected cultures proved that infectious virus was shed from in vitro-infected B cells. Collectively, these data confirm that a variety of ovine B-cell populations can support productive infection by BLV. The development of ovine B-cell cultures permissive for BLV infection provides a controlled system for investigating B-cell leukemogenic processes and the pathogenesis of BLV infection.

  6. 4-Aminopyridine Decreases Progesterone Production by Porcine Granulosa Cells

    Directory of Open Access Journals (Sweden)

    Mitchell Brianna M

    2003-04-01

    Full Text Available Abstract Background Ion channels occur as large families of related genes with cell-specific expression patterns. Granulosa cells have been shown to express voltage-gated potassium channels from more than one family. The purpose of this study was to determine the effects of 4-aminopyridine (4-AP, an antagonist of KCNA but not KCNQ channels. Methods Granulosa cells were isolated from pig follicles and cultured with 4-AP, alone or in combination with FSH, 8-CPT-cAMP, estradiol 17β, and DIDS. Complimentary experiments determined the effects of 4-AP on the spontaneously established pig granulosa cell line PGC-2. Granulosa cell or PGC-2 function was assessed by radio-immunoassay of media progesterone accumulation. Cell viability was assessed by trypan blue exclusion. Drug-induced changes in cell membrane potential and intracellular potassium concentration were documented by spectrophotometric determination of DiBAC4(3 and PBFI fluorescence, respectively. Expression of proliferating cell nuclear antigen (PCNA and steroidogenic acute regulatory protein (StAR was assessed by immunoblotting. Flow cytometry was also used to examine granulosa cell viability and size. Results 4-AP (2 mM decreased progesterone accumulation in the media of serum-supplemented and serum-free granulosa cultures, but inhibited cell proliferation only under serum-free conditions. 4-AP decreased the expression of StAR, the production of cAMP and the synthesis of estradiol by PGC-2. Addition of either 8-CPT-cAMP or estradiol 17β to serum-supplemented primary cultures reduced the inhibitory effects of 4-AP. 4-AP treatment was also associated with increased cell size, increased intracellular potassium concentration, and hyperpolarization of resting membrane potential. The drug-induced hyperpolarization of resting membrane potential was prevented either by decreasing extracellular chloride or by adding DIDS to the media. DIDS also prevented 4-AP inhibition of progesterone production

  7. Human embryonic stem cell lines model experimental human cytomegalovirus latency.

    Science.gov (United States)

    Penkert, Rhiannon R; Kalejta, Robert F

    2013-05-28

    Herpesviruses are highly successful pathogens that persist for the lifetime of their hosts primarily because of their ability to establish and maintain latent infections from which the virus is capable of productively reactivating. Human cytomegalovirus (HCMV), a betaherpesvirus, establishes latency in CD34(+) hematopoietic progenitor cells during natural infections in the body. Experimental infection of CD34(+) cells ex vivo has demonstrated that expression of the viral gene products that drive productive infection is silenced by an intrinsic immune defense mediated by Daxx and histone deacetylases through heterochromatinization of the viral genome during the establishment of latency. Additional mechanistic details about the establishment, let alone maintenance and reactivation, of HCMV latency remain scarce. This is partly due to the technical challenges of CD34(+) cell culture, most notably, the difficulty in preventing spontaneous differentiation that drives reactivation and renders them permissive for productive infection. Here we demonstrate that HCMV can establish, maintain, and reactivate in vitro from experimental latency in cultures of human embryonic stem cells (ESCs), for which spurious differentiation can be prevented or controlled. Furthermore, we show that known molecular aspects of HCMV latency are faithfully recapitulated in these cells. In total, we present ESCs as a novel, tractable model for studies of HCMV latency.

  8. Economic Optimizing Control for Single-Cell Protein Production in a U-Loop Reactor

    DEFF Research Database (Denmark)

    Drejer, André; Ritschel, Tobias Kasper Skovborg; Jørgensen, Sten Bay

    2017-01-01

    The production of single-cell protein (SCP) in a U-loop reactor by a methanotroph is a cost efficient sustainable alternative to protein from fish meal obtained by over-fishing the oceans. SCP serves as animal feed. In this paper, we present a mathematical model that describes the dynamics of SCP...

  9. Numerical simulation model of multijunction solar cell

    NARCIS (Netherlands)

    Babar, M.; Al-Ammar, E.A.; Malik, N.H.

    2012-01-01

    Multi-junction solar cells play an important and significant role in the Concentrated Photovoltaic (CPV) Systems. Recent developments in Concentrated Photovoltaic concerning high power production and cost effective- ness along with better efficiency are due to the advancements in multi-junction

  10. Optimization of radiation protection of cell maintenance of radiopharmaceutical production

    International Nuclear Information System (INIS)

    Machado, Jessica S.; Gerulis, Eduardo; Todo, Alberto S.; Rodrigues Junior, Orlando

    2011-01-01

    This paper performs a study of maintenance tasks realized in production cells to suggest improvements related to the occupational doses based on the optimization principle of the radioprotection. A data survey has been realized of the doses received by the workers during the maintenance. The average values of effective doses are lower than the limits established in the regulations, however can be optimized

  11. Prospective of biodiesel production utilizing microalgae as the cell ...

    African Journals Online (AJOL)

    Microalgae are sunlight-driven miniature factories that convert atmospheric CO2 to polar and neutral lipids which after esterification can be utilized as an alternative source of petroleum. Further, other metabolic products such as bioethanol and biohydrogen produced by algal cells are also being considered for the same ...

  12. Low energy production processes in manufacturing of silicon solar cells

    Science.gov (United States)

    Kirkpatrick, A. R.

    1976-01-01

    Ion implantation and pulsed energy techniques are being combined for fabrication of silicon solar cells totally under vacuum and at room temperature. Simplified sequences allow very short processing times with small process energy consumption. Economic projections for fully automated production are excellent.

  13. FPGA based Control of a Production Cell System

    NARCIS (Netherlands)

    Groothuis, M.A.; van Zuijlen, Jasper J.P.; Broenink, Johannes F.

    Most motion control systems for mechatronic systems are implemented on digital computers. In this paper we present an FPGA based solution implemented on a low cost Xilinx Spartan III FPGA. A Production Cell setup with multiple parallel operating units is chosen as a test case. The embedded control

  14. A new tevchnique for production of amorphous silicon solar cells

    International Nuclear Information System (INIS)

    Andrade, A.M. de; Pereyra, I.; Sanematsu, M.S.; Corgnier, S.L.L.; Fonseca, F.J.

    1984-01-01

    It is presented a new technique for the production of amorphous silicon solar cells based on the development of thin films of a-Si in a reactor in which the decomposition of the sylane, induced by capacitively coupled RF, and the film deposition occur in separate chambers. (M.W.O.) [pt

  15. Human umbilical cord mesenchymal stem cells increase interleukin-9 production of CD4+ T cells

    OpenAIRE

    Yang, Zhou Xin; Chi, Ying; Ji, Yue Ru; Wang, You Wei; Zhang, Jing; Luo, Wei Feng; Li, Li Na; Hu, Cai Dong; Zhuo, Guang Sheng; Wang, Li Fang; Han, Zhi-Bo; Han, Zhong Chao

    2017-01-01

    Mesenchymal stem cells (MSC) are able to differentiate into cells of multiple lineage, and additionally act to modulate the immune response. Interleukin (IL)-9 is primarily produced by cluster of differentiation (CD)4+ T cells to regulate the immune response. The present study aimed to investigate the effect of human umbilical cord derived-MSC (UC-MSC) on IL-9 production of human CD4+ T cells. It was demonstrated that the addition of UC-MSC to the culture of CD4+ T cells significantly enhance...

  16. Cell Therapy and Tissue Engineering Products for Chondral Knee Injuries

    Directory of Open Access Journals (Sweden)

    Adriana Flórez Cabrera

    2017-07-01

    Full Text Available The articular cartilage is prone to suffer lesions of different etiology, being the articular cartilage lesions of the knee the most common. Although most conventional treatments reduce symptoms they lead to the production of fibrocartilage, which has different characteristics than the hyaline cartilage of the joint. There are few therapeutic approaches that promote the replacement of damaged tissue by functional hyaline cartilage. Among them are the so-called advanced therapies, which use cells and tissue engineering products to promote cartilage regeneration. Most of them are based on scaffolds made of different biomaterials, which seeded or not with endogenous or exogenous cells, can be used as cartilage artificial replacement to improve joint function. This paper reviews some therapeutic approaches focused on the regeneration of articular cartilage of the knee and the biomaterials used to develop scaffolds for cell therapy and tissue engineering of cartilage.

  17. Life-cycle analysis of product integrated polymer solar cells

    DEFF Research Database (Denmark)

    Espinosa Martinez, Nieves; García-Valverde, Rafael; Krebs, Frederik C

    2011-01-01

    A life cycle analysis (LCA) on a product integrated polymer solar module is carried out in this study. These assessments are well-known to be useful in developmental stages of a product in order to identify the bottlenecks for the up-scaling in its production phase for several aspects spanning from...... economics through design to functionality. An LCA study was performed to quantify the energy use and greenhouse gas (GHG) emissions from electricity use in the manufacture of a light-weight lamp based on a plastic foil, a lithium-polymer battery, a polymer solar cell, printed circuitry, blocking diode......, switch and a white light emitting semiconductor diode. The polymer solar cell employed in this prototype presents a power conversion efficiency in the range of 2 to 3% yielding energy payback times (EPBT) in the range of 1.3–2 years. Based on this it is worthwhile to undertake a life-cycle study...

  18. Stem-cell-derived products: an FDA update.

    Science.gov (United States)

    Moos, Malcolm

    2008-12-01

    The therapeutic potential of products derived from stem cells of various types has prompted increasing research and development and public attention. Initiation of human clinical trials in the not-too-distant future is now a realistic possibility. It is, therefore, important to weigh the potential benefits against known, theoretical and totally unsuspected risks in light of current knowledge to ensure that subjects participating in these trials are afforded the most reasonable balance possible between potential risks and potential benefits. There are no apparent differences in fundamental, qualitative biological characteristics between stem-cell-derived products and other cellular therapies regulated by the United States Food and Drug Administration (FDA). Existing authorities can, therefore, be applied. Nevertheless, these products do have properties that require careful evaluation.

  19. Radiobiological modelling with MarCell software

    International Nuclear Information System (INIS)

    Hasan, J.S.; Jones, T.D.

    1996-01-01

    Jones introduced a bone marrow radiation cell kinetics model with great potential for application in the fields of health physics, radiation research, and medicine. However, until recently, only the model developers have been able to apply it because of the complex array of biological and physical assignments needed for evaluation of a particular radiation exposure protocol. The purpose of this article is to illustrate the use of MarCell (MARrow CELL Kinetics) software for MS-DOS, a user-friendly computer implementation of that mathematical model that allows almost anyone with an elementary knowledge of radiation physics and/or medical procedures to apply the model. A hands-on demonstration of the software will be given by guiding the user through evaluation of a medical total body irradiation protocol and a nuclear fallout scenario. A brief overview of the software is given in the Appendix

  20. Cardiac Electromechanical Models: From Cell to Organ

    Directory of Open Access Journals (Sweden)

    Natalia A Trayanova

    2011-08-01

    Full Text Available The heart is a multiphysics and multiscale system that has driven the development of the most sophisticated mathematical models at the frontiers of computation physiology and medicine. This review focuses on electromechanical (EM models of the heart from the molecular level of myofilaments to anatomical models of the organ. Because of the coupling in terms of function and emergent behaviors at each level of biological hierarchy, separation of behaviors at a given scale is difficult. Here, a separation is drawn at the cell level so that the first half addresses subcellular/single cell models and the second half addresses organ models. At the subcelluar level, myofilament models represent actin-myosin interaction and Ca-based activation. Myofilament models and their refinements represent an overview of the development in the field. The discussion of specific models emphasizes the roles of cooperative mechanisms and sarcomere length dependence of contraction force, considered the cellular basis of the Frank-Starling law. A model of electrophysiology and Ca handling can be coupled to a myofilament model to produce an EM cell model, and representative examples are summarized to provide an overview of the progression of field. The second half of the review covers organ-level models that require solution of the electrical component as a reaction-diffusion system and the mechanical component, in which active tension generated by the myocytes produces deformation of the organ as described by the equations of continuum mechanics. As outlined in the review, different organ-level models have chosen to use different ionic and myofilament models depending on the specific application; this choice has been largely dictated by compromises between model complexity and computational tractability. The review also addresses application areas of EM models such as cardiac resynchronization therapy and the role of mechano-electric coupling in arrhythmias and

  1. Developing engineering processes through integrated modelling of product and process

    DEFF Research Database (Denmark)

    Nielsen, Jeppe Bjerrum; Hvam, Lars

    2012-01-01

    This article aims at developing an operational tool for integrated modelling of product assortments and engineering processes in companies making customer specific products. Integrating a product model in the design of engineering processes will provide a deeper understanding of the engineering...... activities as well as insight into how product features affect the engineering processes. The article suggests possible ways of integrating models of products with models of engineering processes. The models have been tested and further developed in an action research study carried out in collaboration...... with a major international engineering company....

  2. Marine Natural Products as Models to Circumvent Multidrug Resistance

    Directory of Open Access Journals (Sweden)

    Solida Long

    2016-07-01

    Full Text Available Multidrug resistance (MDR to anticancer drugs is a serious health problem that in many cases leads to cancer treatment failure. The ATP binding cassette (ABC transporter P-glycoprotein (P-gp, which leads to premature efflux of drugs from cancer cells, is often responsible for MDR. On the other hand, a strategy to search for modulators from natural products to overcome MDR had been in place during the last decades. However, Nature limits the amount of some natural products, which has led to the development of synthetic strategies to increase their availability. This review summarizes the research findings on marine natural products and derivatives, mainly alkaloids, polyoxygenated sterols, polyketides, terpenoids, diketopiperazines, and peptides, with P-gp inhibitory activity highlighting the established structure-activity relationships. The synthetic pathways for the total synthesis of the most promising members and analogs are also presented. It is expected that the data gathered during the last decades concerning their synthesis and MDR-inhibiting activities will help medicinal chemists develop potential drug candidates using marine natural products as models which can deliver new ABC transporter inhibitor scaffolds.

  3. Modelling and using product architectures in mechatronic product development

    DEFF Research Database (Denmark)

    Bruun, Hans Peter Lomholt; Mortensen, Niels Henrik

    , experiences by using the architecture representation in a mechatronic development project, and the scope of using the architecture model as a skeleton for a data structure in a PLM system. The fundamental idea for planning and modeling holistic architectures is that an improved understanding of the whole...

  4. Triple co-culture cell model as an in vitro model for oral particulate vaccine systems

    DEFF Research Database (Denmark)

    Nielsen, Line Hagner; De Rossi, C.; Lehr, C-M.

    ; this was not observed with ovalbumin and blank solution. An example of the results is shown in Figure 2 for IL-17A. An established co-culture of Caco-2, THP-1 and MUTZ-3 cells showed promise as an in vitro model for testing of oral vaccine formulations. Mobility of co-culture immune cells as well as cytokine production......A triple co-culture cell model of Caco-2 cells, dendritic cells and macrophages (Figure 1) has previously been developed for studying intestinal permeability in a state of inflammation [1],[2]. The aim of this study was to investigate the applicability of this cell model for testing...... the model antigen ovalbumin was spray dried to obtain a particulate vaccine model system for testing in the cell model. The precursors were shown to form cubosomes when dispersed in aqueous medium, and was therefore used as the vaccine formulation for testing on the co-cultures. After 11 days, the TEER...

  5. Cell-Oriented Modeling of Angiogenesis

    Directory of Open Access Journals (Sweden)

    Diego Guidolin

    2011-01-01

    Full Text Available Due to its significant involvement in various physiological and pathological conditions, angiogenesis (the development of new blood vessels from an existing vasculature represents an important area of the actual biological research and a field in which mathematical modeling proved particularly useful in supporting the experimental work. In this paper, we focus on a specific modeling strategy, known as “cell-centered” approach. This type of mathematical models work at a “mesoscopic scale,” assuming the cell as the natural level of abstraction for computational modeling of development. They treat cells phenomenologically, considering their essential behaviors to study how tissue structure and organization emerge from the collective dynamics of multiple cells. The main contributions of the cell-oriented approach to the study of the angiogenic process will be described. From one side, they have generated “basic science understanding” about the process of capillary assembly during development, growth, and pathology. On the other side, models were also developed supporting “applied biomedical research” for the purpose of identifying new therapeutic targets and clinically relevant approaches for either inhibiting or stimulating angiogenesis.

  6. Cell-oriented modeling of angiogenesis.

    Science.gov (United States)

    Guidolin, Diego; Rebuffat, Piera; Albertin, Giovanna

    2011-01-01

    Due to its significant involvement in various physiological and pathological conditions, angiogenesis (the development of new blood vessels from an existing vasculature) represents an important area of the actual biological research and a field in which mathematical modeling proved particularly useful in supporting the experimental work. In this paper, we focus on a specific modeling strategy, known as "cell-centered" approach. This type of mathematical models work at a "mesoscopic scale," assuming the cell as the natural level of abstraction for computational modeling of development. They treat cells phenomenologically, considering their essential behaviors to study how tissue structure and organization emerge from the collective dynamics of multiple cells. The main contributions of the cell-oriented approach to the study of the angiogenic process will be described. From one side, they have generated "basic science understanding" about the process of capillary assembly during development, growth, and pathology. On the other side, models were also developed supporting "applied biomedical research" for the purpose of identifying new therapeutic targets and clinically relevant approaches for either inhibiting or stimulating angiogenesis.

  7. A minimal physical model for crawling cells

    Science.gov (United States)

    Tiribocchi, Adriano; Tjhung, Elsen; Marenduzzo, Davide; Cates, Michael E.

    Cell motility in higher organisms (eukaryotes) is fundamental to biological functions such as wound healing or immune response, and is also implicated in diseases such as cancer. For cells crawling on solid surfaces, considerable insights into motility have been gained from experiments replicating such motion in vitro. Such experiments show that crawling uses a combination of actin treadmilling (polymerization), which pushes the front of a cell forward, and myosin-induced stress (contractility), which retracts the rear. We present a simplified physical model of a crawling cell, consisting of a droplet of active polar fluid with contractility throughout, but treadmilling connected to a thin layer near the supporting wall. The model shows a variety of shapes and/or motility regimes, some closely resembling cases seen experimentally. Our work supports the view that cellular motility exploits autonomous physical mechanisms whose operation does not need continuous regulatory effort.

  8. PRODUCT TRIAL PROCESSING (PTP): A MODEL APPROACH ...

    African Journals Online (AJOL)

    Admin

    This study is a theoretical approach to consumer's processing of product trail, and equally explored ... consumer's first usage experience with a company's brand or product that is most important in determining ... product, what it is really marketing is the expected ..... confidence, thus there is a positive relationship between ...

  9. Modeling cell-in-cell structure into its biological significance

    OpenAIRE

    He, M-f; Wang, S; Wang, Y; Wang, X-n

    2013-01-01

    Although cell-in-cell structure was noted 100 years ago, the molecular mechanisms of ?entering' and the destination of cell-in-cell remain largely unclear. It takes place among the same type of cells (homotypic cell-in-cell) or different types of cells (heterotypic cell-in-cell). Cell-in-cell formation affects both effector cells and their host cells in multiple aspects, while cell-in-cell death is under more intensive investigation. Given that cell-in-cell has an important role in maintainin...

  10. A Conceptual Model for Production Leveling (Heijunka) Implementation in Batch Production Systems

    OpenAIRE

    De Araujo , Luciano Fonseca; De Queiroz , Abelardo Alves

    2009-01-01

    International audience; This paper explains an implementation model for a new method for Production Leveling designed for batch production system. The main structure of this model is grounded on three constructs: traditional framework for Operations Planning, Lean Manufacturing concepts for Production Leveling and case study guidelines. By combining the first and second construct, a framework for Production Leveling has been developed for batch production systems. Then, case study guidelines ...

  11. Glycoengineering of CHO Cells to Improve Product Quality.

    Science.gov (United States)

    Wang, Qiong; Yin, Bojiao; Chung, Cheng-Yu; Betenbaugh, Michael J

    2017-01-01

    Chinese hamster ovary (CHO) cells represent the predominant platform in biopharmaceutical industry for the production of recombinant biotherapeutic proteins, especially glycoproteins. These glycoproteins include oligosaccharide or glycan attachments that represent one of the principal components dictating product quality. Especially important are the N-glycan attachments present on many recombinant glycoproteins of commercial interest. Furthermore, altering the glycan composition can be used to modulate the production quality of a recombinant biotherapeutic from CHO and other mammalian hosts. This review first describes the glycosylation network in mammalian cells and compares the glycosylation patterns between CHO and human cells. Next genetic strategies used in CHO cells to modulate the sialylation patterns through overexpression of sialyltransfereases and other glycosyltransferases are summarized. In addition, other approaches to alter sialylation including manipulation of sialic acid biosynthetic pathways and inhibition of sialidases are described. Finally, this review also covers other strategies such as the glycosylation site insertion and manipulation of glycan heterogeneity to produce desired glycoforms for diverse biotechnology applications.

  12. Integrated hydrogen production process from cellulose by combining dark fermentation, microbial fuel cells, and a microbial electrolysis cell

    KAUST Repository

    Wang, Aijie; Sun, Dan; Cao, Guangli; Wang, Haoyu; Ren, Nanqi; Wu, Wei-Min; Logan, Bruce E.

    2011-01-01

    Hydrogen gas production from cellulose was investigated using an integrated hydrogen production process consisting of a dark fermentation reactor and microbial fuel cells (MFCs) as power sources for a microbial electrolysis cell (MEC). Two MFCs

  13. Dynamic Modeling of Cell-Free Biochemical Networks Using Effective Kinetic Models

    Directory of Open Access Journals (Sweden)

    Joseph A. Wayman

    2015-03-01

    Full Text Available Cell-free systems offer many advantages for the study, manipulation and modeling of metabolism compared to in vivo processes. Many of the challenges confronting genome-scale kinetic modeling can potentially be overcome in a cell-free system. For example, there is no complex transcriptional regulation to consider, transient metabolic measurements are easier to obtain, and we no longer have to consider cell growth. Thus, cell-free operation holds several significant advantages for model development, identification and validation. Theoretically, genome-scale cell-free kinetic models may be possible for industrially important organisms, such as E. coli, if a simple, tractable framework for integrating allosteric regulation with enzyme kinetics can be formulated. Toward this unmet need, we present an effective biochemical network modeling framework for building dynamic cell-free metabolic models. The key innovation of our approach is the integration of simple effective rules encoding complex allosteric regulation with traditional kinetic pathway modeling. We tested our approach by modeling the time evolution of several hypothetical cell-free metabolic networks. We found that simple effective rules, when integrated with traditional enzyme kinetic expressions, captured complex allosteric patterns such as ultrasensitivity or non-competitive inhibition in the absence of mechanistic information. Second, when integrated into network models, these rules captured classic regulatory patterns such as product-induced feedback inhibition. Lastly, we showed, at least for the network architectures considered here, that we could simultaneously estimate kinetic parameters and allosteric connectivity from synthetic data starting from an unbiased collection of possible allosteric structures using particle swarm optimization. However, when starting with an initial population that was heavily enriched with incorrect structures, our particle swarm approach could converge

  14. Modelling of robotic work cells using agent based-approach

    Science.gov (United States)

    Sękala, A.; Banaś, W.; Gwiazda, A.; Monica, Z.; Kost, G.; Hryniewicz, P.

    2016-08-01

    In the case of modern manufacturing systems the requirements, both according the scope and according characteristics of technical procedures are dynamically changing. This results in production system organization inability to keep up with changes in a market demand. Accordingly, there is a need for new design methods, characterized, on the one hand with a high efficiency and on the other with the adequate level of the generated organizational solutions. One of the tools that could be used for this purpose is the concept of agent systems. These systems are the tools of artificial intelligence. They allow assigning to agents the proper domains of procedures and knowledge so that they represent in a self-organizing system of an agent environment, components of a real system. The agent-based system for modelling robotic work cell should be designed taking into consideration many limitations considered with the characteristic of this production unit. It is possible to distinguish some grouped of structural components that constitute such a system. This confirms the structural complexity of a work cell as a specific production system. So it is necessary to develop agents depicting various aspects of the work cell structure. The main groups of agents that are used to model a robotic work cell should at least include next pattern representatives: machine tool agents, auxiliary equipment agents, robots agents, transport equipment agents, organizational agents as well as data and knowledge bases agents. In this way it is possible to create the holarchy of the agent-based system.

  15. Effects of Selected Physicochemical Parameters on Zerumbone Production of Zingiber zerumbet Smith Cell Suspension Culture.

    Science.gov (United States)

    Jalil, Mahanom; Annuar, Mohamad Suffian Mohamad; Tan, Boon Chin; Khalid, Norzulaani

    2015-01-01

    Zingiber zerumbet Smith is an important herb that contains bioactive phytomedicinal compound, zerumbone. To enhance cell growth and production of this useful compound, we investigated the growth conditions of cell suspension culture. Embryogenic callus generated from shoot bud was used to initiate cell suspension culture. The highest specific growth rate of cells was recorded when it was cultured in liquid Murashige and Skoog basal medium containing 3% sucrose with pH 5.7 and incubated under continuous shaking condition of 70 rpm for 16 h light and 8 h dark cycle at 24°C. Our results also revealed that the type of carbohydrate substrate, light regime, agitation speed, and incubation temperature could affect the production of zerumbone. Although the zerumbone produced in this study was not abundant compared to rhizome of Z. zerumbet, the possibility of producing zerumbone during early stage could serve as a model for subsequent improvement.

  16. Effects of Selected Physicochemical Parameters on Zerumbone Production of Zingiber zerumbet Smith Cell Suspension Culture

    Directory of Open Access Journals (Sweden)

    Mahanom Jalil

    2015-01-01

    Full Text Available Zingiber zerumbet Smith is an important herb that contains bioactive phytomedicinal compound, zerumbone. To enhance cell growth and production of this useful compound, we investigated the growth conditions of cell suspension culture. Embryogenic callus generated from shoot bud was used to initiate cell suspension culture. The highest specific growth rate of cells was recorded when it was cultured in liquid Murashige and Skoog basal medium containing 3% sucrose with pH 5.7 and incubated under continuous shaking condition of 70 rpm for 16 h light and 8 h dark cycle at 24°C. Our results also revealed that the type of carbohydrate substrate, light regime, agitation speed, and incubation temperature could affect the production of zerumbone. Although the zerumbone produced in this study was not abundant compared to rhizome of Z. zerumbet, the possibility of producing zerumbone during early stage could serve as a model for subsequent improvement.

  17. A comparison of production system life cycle models

    Science.gov (United States)

    Attri, Rajesh; Grover, Sandeep

    2012-09-01

    Companies today need to keep up with the rapidly changing market conditions to stay competitive. The main issues in this paper are related to a company's market and its competitors. The prediction of market behavior is helpful for a manufacturing enterprise to build efficient production systems. However, these predictions are usually not reliable. A production system is required to adapt to changing markets, but such requirement entails higher cost. Hence, analyzing different life cycle models of the production system is necessary. In this paper, different life cycle models of the production system are compared to evaluate the distinctive features and the limitations of each model. Furthermore, the difference between product life cycle and production life cycle is summarized, and the effect of product life cycle on production life cycle is explained. Finally, a production system life cycle model, along with key activities to be performed in each stage, is proposed specifically for the manufacturing sector.

  18. Fenofibrate induces ketone body production in melanoma and glioblastoma cells

    Directory of Open Access Journals (Sweden)

    Maja M Grabacka

    2016-02-01

    Full Text Available Ketone bodies (beta-hydroxybutyrate, bHB, acetoacetate are mainly produced in the liver during prolonged fasting or starvation. bHB is a very efficient energy substrate for sustaining ATP production in peripheral tissues; importantly its consumption is preferred over glucose. However, the majority of malignant cells, particularly cancer cells of neuroectodermal origin such as glioblastoma, are not able to use ketone bodies as a source of energy. Here, we report a novel observation that fenofibrate, a synthetic peroxisome proliferator-activated receptor alpha (PPARa agonist, induces bHB production in melanoma and glioblastoma cells, as well as in neurospheres composed of nontransformed cells. Unexpectedly, this effect is not dependent on PPARa activity or its expression level. The fenofibrate-induced ketogenesis is accompanied by growth arrest and down-regulation of transketolase, but the NADP/NADPH and GSH/GSSG ratios remain unaffected. Our results reveal a new, intriguing aspect of cancer cell biology and highlight the benefits of fenofibrate as a supplement to both canonical and dietary (ketogenic therapeutic approaches against glioblastoma.

  19. Merkel cells are long-lived cells whose production is stimulated by skin injury✰

    Science.gov (United States)

    Wright, Margaret C.; Logan, Gregory J.; Bolock, Alexa M.; Kubicki, Adam C.; Hemphill, Julie A.; Sanders, Timothy A.; Maricich, Stephen M.

    2017-01-01

    Mechanosensitive Merkel cells are thought to have finite lifespans, but controversy surrounds the frequency of their replacement and which precursor cells maintain the population. We found by embryonic EdU administration that Merkel cells undergo terminal cell division in late embryogenesis and survive long into adulthood. We also found that new Merkel cells are produced infrequently during normal skin homeostasis and that their numbers do not change during natural or induced hair cycles. In contrast, live imaging and EdU experiments showed that mild mechanical injury produced by skin shaving dramatically increases Merkel cell production. We confirmed with genetic cell ablation and fate-mapping experiments that new touch dome Merkel cells in adult mice arise from touch dome keratinocytes. Together, these independent lines of evidence show that Merkel cells in adult mice are long-lived, are replaced rarely during normal adult skin homeostasis, and that their production can be induced by repeated shaving. These results have profound implications for understanding sensory neurobiology and human diseases such as Merkel cell carcinoma. PMID:27998808

  20. Merkel cells are long-lived cells whose production is stimulated by skin injury.

    Science.gov (United States)

    Wright, Margaret C; Logan, Gregory J; Bolock, Alexa M; Kubicki, Adam C; Hemphill, Julie A; Sanders, Timothy A; Maricich, Stephen M

    2017-02-01

    Mechanosensitive Merkel cells are thought to have finite lifespans, but controversy surrounds the frequency of their replacement and which precursor cells maintain the population. We found by embryonic EdU administration that Merkel cells undergo terminal cell division in late embryogenesis and survive long into adulthood. We also found that new Merkel cells are produced infrequently during normal skin homeostasis and that their numbers do not change during natural or induced hair cycles. In contrast, live imaging and EdU experiments showed that mild mechanical injury produced by skin shaving dramatically increases Merkel cell production. We confirmed with genetic cell ablation and fate-mapping experiments that new touch dome Merkel cells in adult mice arise from touch dome keratinocytes. Together, these independent lines of evidence show that Merkel cells in adult mice are long-lived, are replaced rarely during normal adult skin homeostasis, and that their production can be induced by repeated shaving. These results have profound implications for understanding sensory neurobiology and human diseases such as Merkel cell carcinoma. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Live Cells Decreased Methane Production in Intestinal Content of Pigs

    Directory of Open Access Journals (Sweden)

    Y. L. Gong

    2013-06-01

    Full Text Available An in vitro gas production technique was used in this study to elucidate the effect of two strains of active live yeast on methane (CH4 production in the large intestinal content of pigs to provide an insight to whether active live yeast could suppress CH4 production in the hindgut of pigs. Treatments used in this study include blank (no substrate and no live yeast cells, control (no live yeast cells and yeast (YST supplementation groups (supplemented with live yeast cells, YST1 or YST2. The yeast cultures contained 1.8×1010 cells per g, which were added at the rates of 0.2 mg and 0.4 mg per ml of the fermented inoculum. Large intestinal contents were collected from 2 Duroc×Landrace×Yorkshire pigs, mixed with a phosphate buffer (1:2, and incubated anaerobically at 39°C for 24 h using 500 mg substrate (dry matter (DM basis. Total gas and CH4 production decreased (p<0.05 with supplementation of yeast. The methane production reduction potential (MRP was calculated by assuming net methane concentration for the control as 100%. The MRP of yeast 2 was more than 25%. Compared with the control group, in vitro DM digestibility (IVDMD and total volatile fatty acids (VFA concentration increased (p<0.05 in 0.4 mg/ml YST1 and 0.2 mg/ml YST2 supplementation groups. Proportion of propionate, butyrate and valerate increased (p<0.05, but that of acetate decreased (p<0.05, which led to a decreased (p<0.05 acetate: propionate (A: P ratio in the both YST2 treatments and the 0.4 mg/ml YST 1 supplementation groups. Hydrogen recovery decreased (p<0.05 with yeast supplementation. Quantity of methanogenic archaea per milliliter of inoculum decreased (p<0.05 with yeast supplementation after 24 h of incubation. Our results suggest that live yeast cells suppressed in vitro CH4 production when inoculated into the large intestinal contents of pigs and shifted the fermentation pattern to favor propionate production together with an increased population of acetogenic

  2. Giant Glial Cell: New Insight Through Mechanism-Based Modeling

    DEFF Research Database (Denmark)

    Postnov, D. E.; Ryazanova, L. S.; Brazhe, Nadezda

    2008-01-01

    The paper describes a detailed mechanism-based model of a tripartite synapse consisting of P- and R-neurons together with a giant glial cell in the ganglia of the medical leech (Hirudo medicinalis), which is a useful object for experimental studies in situ. We describe the two main pathways...... of the glial cell activation: (1) via IP3 production and Ca2+ release from the endoplasmic reticulum and (2) via increase of the extracellular potassium concentration, glia depolarization, and opening of voltage-dependent Ca2+ channels. We suggest that the second pathway is the more significant...

  3. A product feature-based user-centric product search model

    OpenAIRE

    Ben Jabeur, Lamjed; Soulier, Laure; Tamine, Lynda; Mousset, Paul

    2016-01-01

    During the online shopping process, users would search for interesting products and quickly access those that fit with their needs among a long tail of similar or closely related products. Our contribution addresses head queries that are frequently submitted on e-commerce Web sites. Head queries usually target featured products with several variations, accessories, and complementary products. We present in this paper a product feature-based user-centric model for product search involving in a...

  4. Determination of membrane degradation products in the product water of polymer electrolyte membrane fuel cells using liquid chromatography mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zedda, Marco

    2011-05-12

    The predominant long term failure of polymer electrolyte membranes (PEM) is caused by hydroxyl radicals generated during fuel cell operation. These radicals attack the polymer, leading to chain scission, unzipping and consequently to membrane decomposition products. The present work has investigated decomposition products of novel sulfonated aromatic hydrocarbon membranes on the basis of a product water analysis. Degradation products from the investigated membrane type and the possibility to detect these compounds in the product water for diagnostic purposes have not been discovered yet. This thesis demonstrates the potential of solid phase extraction and liquid chromatography tandem mass spectrometry (SPE-LC-MS/MS) for the extraction, separation, characterization, identification and quantification of membrane degradation products in the product water of fuel cells. For this purpose, several polar aromatic hydrocarbons with different functional groups were selected as model compounds for the development of reliable extraction, separation and detection methods. The results of this thesis have shown that mixed mode sorbent materials with both weak anion exchange and reversed phase retention properties are well suited for reproducible extraction of both molecules and ions from the product water. The chromatographic separation of various polar aromatic hydrocarbons was achieved by means of phase optimized liquid chromatography using a solvent gradient and on a C18 stationary phase. Sensitive and selective detection of model compounds could be successfully demonstrated by the analysis of the product water using tandem mass spectrometry. The application of a hybrid mass spectrometer (Q Trap) for the characterization of unknown polar aromatic hydrocarbons has led to the identification and confirmation of 4-hydroxybenzoic acid in the product water. In addition, 4-HBA could be verified as a degradation product resulting from PEM decomposition by hydroxyl radicals using an

  5. Improved Cell Culture Method for Growing Contracting Skeletal Muscle Models

    Science.gov (United States)

    Marquette, Michele L.; Sognier, Marguerite A.

    2013-01-01

    An improved method for culturing immature muscle cells (myoblasts) into a mature skeletal muscle overcomes some of the notable limitations of prior culture methods. The development of the method is a major advance in tissue engineering in that, for the first time, a cell-based model spontaneously fuses and differentiates into masses of highly aligned, contracting myotubes. This method enables (1) the construction of improved two-dimensional (monolayer) skeletal muscle test beds; (2) development of contracting three-dimensional tissue models; and (3) improved transplantable tissues for biomedical and regenerative medicine applications. With adaptation, this method also offers potential application for production of other tissue types (i.e., bone and cardiac) from corresponding precursor cells.

  6. A survey on the geometry of production models in economics

    Directory of Open Access Journals (Sweden)

    Alina-Daniela Vîlcu

    2017-01-01

    Full Text Available In this article we survey selected recent results on the geometry of production models, focussing on the main production functions that are usually analyzed in economics, namely homogeneous, homothetic, quasi-sum and quasi-product production functions.

  7. A stochastic model of epigenetic dynamics in somatic cell reprogramming

    Directory of Open Access Journals (Sweden)

    Max eFloettmann

    2012-06-01

    Full Text Available Somatic cell reprogramming has dramatically changed stem cell research inrecent years. The high pace of new findings in the field and an ever increasingamount of data from new high throughput techniques make it challengingto isolate core principles of the process. In order to analyze suchmechanisms, we developed an abstract mechanistic model of a subset of theknown regulatory processes during cell differentiation and production of inducedpluripotent stem cells. This probabilistic Boolean network describesthe interplay between gene expression, chromatin modifications and DNAmethylation. The model incorporates recent findings in epigenetics and reproducesexperimentally observed reprogramming efficiencies and changes inmethylation and chromatin remodeling. It enables us to investigate in detail,how the temporal progression of the process is regulated. It also explicitlyincludes the transduction of factors using viral vectors and their silencing inreprogrammed cells, since this is still a standard procedure in somatic cellreprogramming. Based on the model we calculate an epigenetic landscape.Simulation results show good reproduction of experimental observations duringreprogramming, despite the simple stucture of the model. An extensiveanalysis and introduced variations hint towards possible optimizations of theprocess, that could push the technique closer to clinical applications. Fasterchanges in DNA methylation increase the speed of reprogramming at theexpense of efficiency, while accelerated chromatin modifications moderatelyimprove efficiency.

  8. Triple co-culture cell model as an in vitro model for oral particulate vaccine systems

    DEFF Research Database (Denmark)

    Nielsen, Line Hagner; De Rossi, C.; Lehr, C.-M.

    the immunostimulatory ability of particulate vaccine formulations designed for oral delivery. Levels of cytokine production in response to vaccine administration were measured following particulate vaccine administration, as an indication of dendritic cell and macrophage activation. Precursors of cubosomes containing......; this was not observed with ovalbumin and blank solution. An example of the results is shown in Figure 2 for IL-17A. An established co-culture of Caco-2, THP-1 and MUTZ-3 cells showed promise as an in vitro model for testing of oral vaccine formulations. Mobility of co-culture immune cells as well as cytokine production...... with particle formulations. This was not the case when incubating with ovalbumin solution or blank. The ELISA screening assay showed production of a wide range of cytokines following culture incubation with cubosomes (with and without ovalbumin) and LPS solutions, indicative of a stimulatory effect...

  9. Whey utilization for single-cell protein production

    Energy Technology Data Exchange (ETDEWEB)

    Barraquio, V; Silverio, L G; Revilleza, R P; Fernadez, W L

    1980-01-01

    The production of single-cell protein by yeast assimilation of lactose in soft cheese whey was studied using Candida pseudotropicalis as a test organism. Under shake-flask cultivation conditions with deproteinized whey as the medium, lactose (initially 4.20%) was completely assimilated in 48h; cell mass was 5.56 mg/mL after 72h; and average protein content of the dried mass was approximately 11.8%. Batch cultivation using undeproteinized whey resulted in a faster lactose utilization rate from an initial 3.93% to a residual 0.56% in 12 h; cell mass was 8.41 mg/mL in 10 h; and average protein was approximately 37.7%. In a semicontinuous culture with 10 to the power of 7 viable cells/mL as initial cell concentration, 15.69 mg/mL cell mass with a mean protein content of approximately 21.4% could be produced and lactose could be considerably consumed (from an initial 4.75% to a residual 0.42%) within 13-14 h. Supplementation with (NH/sub 4/)/sub 2/S0/sub 4/ and KH/sub 2/P0/sub 4/ did not increase cell mass (12.47 mg/mL in 12 h) and hasten lactose assimulation (from initial 4.49% to residual 0.3% in 12 h). Average protein content was approximately 31%. Cell mass yield was established as 0.29 mg yeast cell/mg lactose consumed. Factors that might have affected protein content are also discussed.

  10. A Model to Improve the Quality Products

    Directory of Open Access Journals (Sweden)

    Hasan GOKKAYA

    2010-08-01

    Full Text Available The topic of this paper is to present a solution who can improve product qualityfollowing the idea: “Unlike people who have verbal skills, machines use "sign language"to communicate what hurts or what has invaded their system’. Recognizing the "signs"or symptoms that the machine conveys is a required skill for those who work withmachines and are responsible for their care and feeding. The acoustic behavior of technical products is predominantly defined in the design stage, although the acoustic characteristics of machine structures can be analyze and give a solution for the actual products and create a new generation of products. The paper describes the steps intechnological process for a product and the solution who will reduce the costs with the non-quality of product and improve the management quality.

  11. Network model of project "Lean Production"

    Science.gov (United States)

    Khisamova, E. D.

    2018-05-01

    Economical production implies primarily new approaches to culture of management and organization of production and offers a set of tools and techniques that allows reducing losses significantly and making the process cheaper and faster. Economical production tools are simple solutions that allow one to see opportunities for improvement of all aspects of the business, to reduce losses significantly, to constantly improve the whole spectrum of business processes, to increase significantly the transparency and manageability of the organization, to take advantage of the potential of each employee of the company, to increase competitiveness, and to obtain significant economic benefits without making large financial expenditures. Each of economical production tools solves a specific part of the problems, and only application of their combination will allow one to solve the problem or minimize it to acceptable values. The research of the governance process project "Lean Production" permitted studying the methods and tools of lean production and developing measures for their improvement.

  12. Bifurcation analysis of a product inhibition model of a continuous fermentation process

    Energy Technology Data Exchange (ETDEWEB)

    Lenbury, Y; Chiaranai, C

    1987-03-01

    A product inhibition model of a continuous fermentation process is considered. If the yield term is a variable function of ethanol concentration, oscillation in the cell and ethanol concentrations is shown to be a Hopf bifurcation in the underlying system of nonlinear, ordinary differential equations which comprises the model.

  13. Astaxanthin increases progesterone production in cultured bovine luteal cells.

    Science.gov (United States)

    Kamada, Hachiro; Akagi, Satoshi; Watanabe, Shinya

    2017-06-29

    Although astaxanthin (AST) is known to be a strong antioxidant, its effects on reproductive function in domestic animals have not yet been elucidated in detail. Therefore, we investigated the effects of AST on luteal cells, which produce progesterone (P4), an important hormone for maintaining pregnancy. Luteal cells were prepared by collagenase dispersion of the corpus luteum (CL). The addition of racemic AST at a low concentration (production than RR-AST. When 1 mg/kg·body weight of SS-AST derived from green algae was fed to cows for 2 weeks, its concentration in blood plasma was 10.9 nM on average, which was sufficient to expect an in vitro effect on the production of P4 in cows. These results suggested the potential of SS-AST supplements for cows to elevate luteal function.

  14. A model for 'sustainable' US beef production.

    Science.gov (United States)

    Eshel, Gidon; Shepon, Alon; Shaket, Taga; Cotler, Brett D; Gilutz, Stav; Giddings, Daniel; Raymo, Maureen E; Milo, Ron

    2018-01-01

    Food production dominates land, water and fertilizer use and is a greenhouse gas source. In the United States, beef production is the main agricultural resource user overall, as well as per kcal or g of protein. Here, we offer a possible, non-unique, definition of 'sustainable' beef as that subsisting exclusively on grass and by-products, and quantify its expected US production as a function of pastureland use. Assuming today's pastureland characteristics, all of the pastureland that US beef currently use can sustainably deliver ≈45% of current production. Rewilding this pastureland's less productive half (≈135 million ha) can still deliver ≈43% of current beef production. In all considered scenarios, the ≈32 million ha of high-quality cropland that beef currently use are reallocated for plant-based food production. These plant items deliver 2- to 20-fold more calories and protein than the replaced beef and increase the delivery of protective nutrients, but deliver no B 12 . Increased deployment of rapid rotational grazing or grassland multi-purposing may increase beef production capacity.

  15. PTEN drives Th17 cell differentiation by preventing IL-2 production.

    Science.gov (United States)

    Kim, Hyeong Su; Jang, Sung Woong; Lee, Wonyong; Kim, Kiwan; Sohn, Hyogon; Hwang, Soo Seok; Lee, Gap Ryol

    2017-11-06

    T helper 17 (Th17) cells are a CD4 + T cell subset that produces IL-17A to mediate inflammation and autoimmunity. IL-2 inhibits Th17 cell differentiation. However, the mechanism by which IL-2 is suppressed during Th17 cell differentiation remains unclear. Here, we show that phosphatase and tensin homologue (PTEN) is a key factor that regulates Th17 cell differentiation by suppressing IL-2 production. Th17-specific Pten deletion ( Pten fl/fl Il17a cre ) impairs Th17 cell differentiation in vitro and ameliorated symptoms of experimental autoimmune encephalomyelitis (EAE), a model of Th17-mediated autoimmune disease. Mechanistically, Pten deficiency up-regulates IL-2 and phosphorylation of STAT5, but reduces STAT3 phosphorylation, thereby inhibiting Th17 cell differentiation. PTEN inhibitors block Th17 cell differentiation in vitro and in the EAE model. Thus, PTEN plays a key role in Th17 cell differentiation by blocking IL-2 expression. © 2017 Kim et al.

  16. A quality risk management model approach for cell therapy manufacturing.

    Science.gov (United States)

    Lopez, Fabio; Di Bartolo, Chiara; Piazza, Tommaso; Passannanti, Antonino; Gerlach, Jörg C; Gridelli, Bruno; Triolo, Fabio

    2010-12-01

    International regulatory authorities view risk management as an essential production need for the development of innovative, somatic cell-based therapies in regenerative medicine. The available risk management guidelines, however, provide little guidance on specific risk analysis approaches and procedures applicable in clinical cell therapy manufacturing. This raises a number of problems. Cell manufacturing is a poorly automated process, prone to operator-introduced variations, and affected by heterogeneity of the processed organs/tissues and lot-dependent variability of reagent (e.g., collagenase) efficiency. In this study, the principal challenges faced in a cell-based product manufacturing context (i.e., high dependence on human intervention and absence of reference standards for acceptable risk levels) are identified and addressed, and a risk management model approach applicable to manufacturing of cells for clinical use is described for the first time. The use of the heuristic and pseudo-quantitative failure mode and effect analysis/failure mode and critical effect analysis risk analysis technique associated with direct estimation of severity, occurrence, and detection is, in this specific context, as effective as, but more efficient than, the analytic hierarchy process. Moreover, a severity/occurrence matrix and Pareto analysis can be successfully adopted to identify priority failure modes on which to act to mitigate risks. The application of this approach to clinical cell therapy manufacturing in regenerative medicine is also discussed. © 2010 Society for Risk Analysis.

  17. Multivariable control system for dynamic PEM fuel cell model

    International Nuclear Information System (INIS)

    Tanislav, Vasile; Carcadea, Elena; Capris, Catalin; Culcer, Mihai; Raceanu, Mircea

    2010-01-01

    Full text: The main objective of this work was to develop a multivariable control system of robust type for a PEM fuel cells assembly. The system will be used in static and mobile applications for different values of power, generated by a fuel cell assembly of up to 10 kW. Intermediate steps were accomplished: a study of a multivariable control strategy for a PEM fuel cell assembly; a mathematic modeling of mass and heat transfer inside of fuel cell assembly, defining the response function to hydrogen and oxygen/air mass flow and inlet pressure changes; a testing stand for fuel cell assembly; experimental determinations of transient response for PEM fuel cell assembly, and more others. To define the multivariable control system for a PEM fuel cell assembly the parameters describing the system were established. Also, there were defined the generic mass and energy balance equations as functions of derivative of m i , in and m i , out , representing the mass going into and out from the fuel cell, while Q in is the enthalpy and Q out is the enthalpy of the unused reactant gases and heat produced by the product, Q dis is the heat dissipated to the surroundings, Q c is the heat taken away from the stack by active cooling and W el is the electricity generated. (authors)

  18. Modelling and optimization of environmental conditions for kefiran production by Lactobacillus kefiranofaciens.

    Science.gov (United States)

    Cheirsilp, B; Shimizu, H; Shioya, S

    2001-12-01

    A mathematical model for kefiran production by Lactobacillus kefiranofaciens was established, in which the effects of pH, substrate and product on cell growth, exopolysaccharide formation and substrate assimilation were considered. The model gave a good representation both of the formation of exopolysaccharides (which are not only attached to cells but also released into the medium) and of the time courses of the production of galactose and glucose in the medium (which are produced and consumed by the cells). Since pH and both lactose and lactic acid concentrations differently affected production and growth activity, the model included the effects of pH and the concentrations of lactose and lactic acid. Based on the mathematical model, an optimal pH profile for the maximum production of kefiran in batch culture was obtained. In this study, a simplified optimization method was developed, in which the optimal pH profile was determined at a particular final fermentation time. This was based on the principle that, at a certain time, switching from the maximum specific growth rate to the critical one (which yields the maximum specific production rate) results in maximum production. Maximum kefiran production was obtained, which was 20% higher than that obtained in the constant-pH control fermentation. A genetic algorithm (GA) was also applied to obtain the optimal pH profile; and it was found that practically the same solution was obtained using the GA.

  19. New filterability and compressibility test cell design for nuclear products

    Energy Technology Data Exchange (ETDEWEB)

    Féraud, J.P. [CEA Marcoule, DTEC/SGCS/LGCI, BP 17171, 30207 Bagnols-sur-Cèze (France); Bourcier, D., E-mail: damien.bourcier@cea.fr [CEA Marcoule, DTEC/SGCS/LGCI, BP 17171, 30207 Bagnols-sur-Cèze (France); Ode, D. [CEA Marcoule, DTEC/SGCS/LGCI, BP 17171, 30207 Bagnols-sur-Cèze (France); Puel, F. [Université Lyon 1, Villeurbanne (France); CNRS, UMR5007, Laboratoire d‘Automatique et de Génie des Procédés (LAGEP), CPE-Lyon, 43 bd du 11 Novembre 1918, 69100 Villeurbanne (France)

    2013-12-15

    Highlights: • Test easily usable without tools in a glove box. • The test minimizes the slurry volume necessary for this type of study. • The test characterizes the flow resistance in a porous medium in formation. • The test is performed at four pressure levels to determine the compressibility. • The technical design ensures reproducible flow resistance measurements. -- Abstract: Filterability and compressibility tests are often carried out at laboratory scale to obtain data required to scale up solid/liquid separation processes. Current technologies, applied with a constant pressure drop, enable specific resistance and cake formation rate measurement in accordance with a modified Darcy's law. The new test cell design described in this paper is easily usable without tools in a glove box and minimizes the slurry volume necessary for this type of study. This is an advantage for investigating toxic and hazardous products such as radioactive materials. Uranium oxalate precipitate slurries were used to test and validate this new cell. In order to reduce the test cell volume, a statistical approach was applied on 8 results obtained with cylindrical test cells of 1.8 cm and 3 cm in diameter. Wall effects can therefore be ignored despite the small filtration cell diameter, allowing tests to be performed with only about one-tenth of the slurry volume of a standard commercial cell. The significant reduction in the size of this experimental device does not alter the consistency of filtration data which may be used in the design of industrial equipment.

  20. New filterability and compressibility test cell design for nuclear products

    International Nuclear Information System (INIS)

    Féraud, J.P.; Bourcier, D.; Ode, D.; Puel, F.

    2013-01-01

    Highlights: • Test easily usable without tools in a glove box. • The test minimizes the slurry volume necessary for this type of study. • The test characterizes the flow resistance in a porous medium in formation. • The test is performed at four pressure levels to determine the compressibility. • The technical design ensures reproducible flow resistance measurements. -- Abstract: Filterability and compressibility tests are often carried out at laboratory scale to obtain data required to scale up solid/liquid separation processes. Current technologies, applied with a constant pressure drop, enable specific resistance and cake formation rate measurement in accordance with a modified Darcy's law. The new test cell design described in this paper is easily usable without tools in a glove box and minimizes the slurry volume necessary for this type of study. This is an advantage for investigating toxic and hazardous products such as radioactive materials. Uranium oxalate precipitate slurries were used to test and validate this new cell. In order to reduce the test cell volume, a statistical approach was applied on 8 results obtained with cylindrical test cells of 1.8 cm and 3 cm in diameter. Wall effects can therefore be ignored despite the small filtration cell diameter, allowing tests to be performed with only about one-tenth of the slurry volume of a standard commercial cell. The significant reduction in the size of this experimental device does not alter the consistency of filtration data which may be used in the design of industrial equipment

  1. A bistable model of cell polarity.

    Directory of Open Access Journals (Sweden)

    Matteo Semplice

    Full Text Available Ultrasensitivity, as described by Goldbeter and Koshland, has been considered for a long time as a way to realize bistable switches in biological systems. It is not as well recognized that when ultrasensitivity and reinforcing feedback loops are present in a spatially distributed system such as the cell plasmamembrane, they may induce bistability and spatial separation of the system into distinct signaling phases. Here we suggest that bistability of ultrasensitive signaling pathways in a diffusive environment provides a basic mechanism to realize cell membrane polarity. Cell membrane polarization is a fundamental process implicated in several basic biological phenomena, such as differentiation, proliferation, migration and morphogenesis of unicellular and multicellular organisms. We describe a simple, solvable model of cell membrane polarization based on the coupling of membrane diffusion with bistable enzymatic dynamics. The model can reproduce a broad range of symmetry-breaking events, such as those observed in eukaryotic directional sensing, the apico-basal polarization of epithelium cells, the polarization of budding and mating yeast, and the formation of Ras nanoclusters in several cell types.

  2. Toy model for pion production in nucleon-nucleon collisions

    International Nuclear Information System (INIS)

    Hanhart, C.; Miller, G. A.; Myhrer, F.; Sato, T.; Kolck, U. van

    2001-01-01

    We develop a toy model for pion production in nucleon-nucleon collisions that reproduces some of the features of the chiral Lagrangian calculations. We calculate the production amplitude and examine some common approximations

  3. A product-model supporting coupling's management during microproduct design

    DEFF Research Database (Denmark)

    Museau, Matthieu; De Grave, Arnaud; Masclet, Cedric

    2009-01-01

    Microproducts show specificities compared to macroproducts and their design processes differ. Nowadays, existing design tools manage microproduct specificities too late during the design process, only after the first product representation is available. This article presents a product-model able...

  4. Voronoi cell patterns: Theoretical model and applications

    Science.gov (United States)

    González, Diego Luis; Einstein, T. L.

    2011-11-01

    We use a simple fragmentation model to describe the statistical behavior of the Voronoi cell patterns generated by a homogeneous and isotropic set of points in 1D and in 2D. In particular, we are interested in the distribution of sizes of these Voronoi cells. Our model is completely defined by two probability distributions in 1D and again in 2D, the probability to add a new point inside an existing cell and the probability that this new point is at a particular position relative to the preexisting point inside this cell. In 1D the first distribution depends on a single parameter while the second distribution is defined through a fragmentation kernel; in 2D both distributions depend on a single parameter. The fragmentation kernel and the control parameters are closely related to the physical properties of the specific system under study. We use our model to describe the Voronoi cell patterns of several systems. Specifically, we study the island nucleation with irreversible attachment, the 1D car-parking problem, the formation of second-level administrative divisions, and the pattern formed by the Paris Métro stations.

  5. Benchmarking of commercially available CHO cell culture media for antibody production.

    Science.gov (United States)

    Reinhart, David; Damjanovic, Lukas; Kaisermayer, Christian; Kunert, Renate

    2015-06-01

    In this study, eight commercially available, chemically defined Chinese hamster ovary (CHO) cell culture media from different vendors were evaluated in batch culture using an IgG-producing CHO DG44 cell line as a model. Medium adaptation revealed that the occurrence of even small aggregates might be a good indicator of cell growth performance in subsequent high cell density cultures. Batch experiments confirmed that the culture medium has a significant impact on bioprocess performance, but high amino acid concentrations alone were not sufficient to ensure superior cell growth and high antibody production. However, some key amino acids that were limiting in most media could be identified. Unbalanced glucose and amino acids led to high cell-specific lactate and ammonium production rates. In some media, persistently high glucose concentrations probably induced the suppression of respiration and oxidative phosphorylation, known as Crabtree effect, which resulted in high cell-specific glycolysis rates along with a continuous and high lactate production. In additional experiments, two of the eight basal media were supplemented with feeds from two different manufacturers in six combinations, in order to understand the combined impact of media and feeds on cell metabolism in a CHO fed-batch process. Cell growth, nutrient consumption and metabolite production rates, antibody production, and IgG quality were evaluated in detail. Concentrated feed supplements boosted cell concentrations almost threefold and antibody titers up to sevenfold. Depending on the fed-batch strategy, fourfold higher peak cell concentrations and eightfold increased IgG titers (up to 5.8 g/L) were achieved. The glycolytic flux was remarkably similar among the fed-batches; however, substantially different specific lactate production rates were observed in the different media and feed combinations. Further analysis revealed that in addition to the feed additives, the basal medium can make a considerable

  6. Architecture of the Product State Model Environment

    DEFF Research Database (Denmark)

    Holm Larsen, Michael; Lynggaard, Hans Jørgen B.

    2003-01-01

    on thedevelopment activities of the PSM architecture. An example discusses how to handle product relatedinformation on the shop floor in a manufacturing company and focuses on how dynamically updatedproduct data can improve control of production activities. This prototype example of welding a jointbetween two steel...... plates serves as proof of concept for the PSM architecture....

  7. Production of membrane proteins without cells or detergents.

    Science.gov (United States)

    Rajesh, Sundaresan; Knowles, Timothy; Overduin, Michael

    2011-04-30

    The production of membrane proteins in cellular systems is besieged by several problems due to their hydrophobic nature which often causes misfolding, protein aggregation and cytotoxicity, resulting in poor yields of stable proteins. Cell-free expression has emerged as one of the most versatile alternatives for circumventing these obstacles by producing membrane proteins directly into designed hydrophobic environments. Efficient optimisation of expression and solubilisation conditions using a variety of detergents, membrane mimetics and lipids has yielded structurally and functionally intact membrane proteins, with yields several fold above the levels possible from cell-based systems. Here we review recently developed techniques available to produce functional membrane proteins, and discuss amphipols, nanodisc and styrene maleic acid lipid particle (SMALP) technologies that can be exploited alongside cell-free expression of membrane proteins. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. A model for individual egg production in chickens

    NARCIS (Netherlands)

    Grossman, M.; Koops, W.J.

    2001-01-01

    Our primary objective was to improve on an existing model for the individual weekly egg production curve by modeling the curve as a sum of logistic functions: one for the increasing phase of production and a sum for the decreasing phases. To illustrate the model, we used four data sets from two

  9. The methoxychlor metabolite, HPTE, inhibits rat luteal cell progesterone production.

    Science.gov (United States)

    Akgul, Yucel; Derk, Raymond C; Meighan, Terence; Rao, K Murali Krishna; Murono, Eisuke P

    2011-07-01

    The methoxychlor metabolite, HPTE, was shown to inhibit P450-cholesterol side-chain cleavage (P450scc) activity resulting in decreased progesterone production by cultured ovarian follicular cells in previous studies. It is not known whether HPTE has any effect on progesterone formation by the corpus luteum. Exposure to 100 nM HPTE reduced progesterone production by luteal cells with progressive declines to progesterone formation and P450scc catalytic activity of hCG- or 8 Br-cAMP-stimulated luteal cells. However, HPTE did not alter mRNA and protein levels of P450scc. Compounds acting as estrogen (17 β-estradiol, bisphenol-A or octylphenol), antiestrogen (ICI) or antiandrogen (monobutyl phthalate, flutamide or M-2) added alone to luteal cells did not mimic the action of HPTE on progesterone and P450scc activity. These results suggest that HPTE directly inhibits P450scc catalytic activity resulting in reduced progesterone formation, and this action was not mediated through estrogen or androgen receptors. Published by Elsevier Inc.

  10. Electricity production from microbial fuel cell by using yeast

    International Nuclear Information System (INIS)

    Vorasingha, A.; Souvakon, C.; Boonchom, K.

    2006-01-01

    The continuous search for methods to generate electricity from renewable sources such as water, solar energy, wind, nuclear or chemicals was discussed with particular focus on attaining the full power of the microbial fuel cell (MFC). Under ideal environmental conditions, the only byproducts of a biofuel cell would be water and carbon dioxide (CO 2 ). The production of energy from renewables such as biomass is important for sustainable development and reducing global emissions of CO 2 . Hydrogen can also be an important component of an energy infrastructure that reduces CO 2 emissions if the hydrogen is produced from renewable sources and used in fuel cells. Hydrogen gas can be biologically produced at high concentration from the fermentation of high sugar substrates such as glucose and sucrose. Some of the issues of MFC design were addressed, including the use of cheap substrates to derive microbial electricity. In the MFC, yeast donates electrons to a chemical electron mediator, which in turn transfers the electrons to an electrode, producing electricity. Experimental results showed that glucose yielded the highest peak voltage, but a semi-processed sugar and molasses were similar to glucose in the electricity production pattern. It was noted that this technology is only at the research stages, and more research is needed before household microbial fuel cells can be made available for producing power for prolonged periods of time. Future research efforts will focus on increasing the efficiency, finding alternatives to hazardous electron mediators and finding new microbes. 12 refs., 6 figs

  11. Conceptual Modelling for Product Configuration Systems

    DEFF Research Database (Denmark)

    Shafiee, Sara

    Individual customization of goods and processes in different industries leads to complexity due to a growing mix of products both regarding characteristics of products and support services. In order to eliminate complexity and challenges in product/process customizing, smart IT systems called...... Product Configuration Systems (PCS), have been proposed as the solution both by researchers and practitioners and various benefits are mentioned from utilizing PCSs. Based on the latest literature, there are challenges reported in all phases of PCS projects including planning, development......, and documentation. Moreover, the challenges become more serious when it involves complicated products/processes in engineer-to-order (ETO) companies. The purpose of this thesis is to contribute to the existing knowledge of managing PCS projects by proposing frameworks and tools to address some of the main...

  12. Photocatalysis for Renewable Energy Production Using PhotoFuelCells

    Directory of Open Access Journals (Sweden)

    Robert Michal

    2014-11-01

    Full Text Available The present work is a short review of our recent studies on PhotoFuelCells, that is, photoelectrochemical cells which consume a fuel to produce electricity or hydrogen, and presents some unpublished data concerning both electricity and hydrogen production. PhotoFuelCells have been constructed using nanoparticulate titania photoanodes and various cathode electrodes bearing a few different types of electrocatalyst. In the case where the cell functioned with an aerated cathode, the cathode electrode was made of carbon cloth carrying a carbon paste made of carbon black and dispersed Pt nanoparticles. When the cell was operated in the absence of oxygen, the electrocatalyst was deposited on an FTO slide using a special commercial carbon paste, which was again enriched with Pt nanoparticles. Mixing of Pt with carbon paste decreased the quantity of Pt necessary to act as electrocatalyst. PhotoFuelCells can produce electricity without bias and with relatively high open-circuit voltage when they function in the presence of fuel and with an aerated cathode. In that case, titania can be sensitized in the visible region by CdS quantum dots. In the present work, CdS was deposited by the SILAR method. Other metal chalcogenides are not functional as sensitizers because the combined photoanode in their presence does not have enough oxidative power to oxidize the fuel. Concerning hydrogen production, it was found that it is difficult to produce hydrogen in an alkaline environment even under bias, however, this is still possible if losses are minimized. One way to limit losses is to short-circuit anode and cathode electrode and put them close together. This is achieved in the “photoelectrocatalytic leaf”, which was presently demonstrated capable of producing hydrogen even in a strongly alkaline environment.

  13. Modeling human infertility with pluripotent stem cells

    Directory of Open Access Journals (Sweden)

    Di Chen

    2017-05-01

    Full Text Available Human fertility is dependent upon the correct establishment and differentiation of the germline. This is because no other cell type in the body is capable of passing a genome and epigenome from parent to child. Terminally differentiated germline cells in the adult testis and ovary are called gametes. However, the initial specification of germline cells occurs in the embryo around the time of gastrulation. Most of our knowledge regarding the cell and molecular events that govern human germline specification involves extrapolating scientific principles from model organisms, most notably the mouse. However, recent work using next generation sequencing, gene editing and differentiation of germline cells from pluripotent stem cells has revealed that the core molecular mechanisms that regulate human germline development are different from rodents. Here, we will discuss the major molecular pathways required for human germline differentiation and how pluripotent stem cells have revolutionized our ability to study the earliest steps in human embryonic lineage specification in order to understand human fertility.

  14. Modelling production system architectures in the early phases of product development

    DEFF Research Database (Denmark)

    Guðlaugsson, Tómas Vignir; Ravn, Poul Martin; Mortensen, Niels Henrik

    2016-01-01

    are needed and appropriate to enable determination of obtainable product quality. In order to meet this challenge, it is suggested that a visual modelling framework be adopted that clarifies which product and production features are known at a specific time of the project and which features will be worked...... on – leading to an improved basis for prioritizing activities in the project. Requirements for the contents of the framework are presented, and literature on production and system models is reviewed. The production system architecture modelling framework is founded on methods and approaches in literature......This article suggests a framework for modelling a production system architecture in the early phases of product development.The challenge in these phases is that the products to be produced are not completely defined and yet decisions need to be made early in the process on what investments...

  15. Cost Analysis of Direct Methanol Fuel Cell Stacks for Mass Production

    Directory of Open Access Journals (Sweden)

    Mauro Francesco Sgroi

    2016-11-01

    Full Text Available Fuel cells are very promising technologies for efficient electrical energy generation. The development of enhanced system components and new engineering solutions is fundamental for the large-scale deployment of these devices. Besides automotive and stationary applications, fuel cells can be widely used as auxiliary power units (APUs. The concept of a direct methanol fuel cell (DMFC is based on the direct feed of a methanol solution to the fuel cell anode, thus simplifying safety, delivery, and fuel distribution issues typical of conventional hydrogen-fed polymer electrolyte fuel cells (PEMFCs. In order to evaluate the feasibility of concrete application of DMFC devices, a cost analysis study was carried out in the present work. A 200 W-prototype developed in the framework of a European Project (DURAMET was selected as the model system. The DMFC stack had a modular structure allowing for a detailed evaluation of cost characteristics related to the specific components. A scale-down approach, focusing on the model device and projected to a mass production, was used. The data used in this analysis were obtained both from research laboratories and industry suppliers specialising in the manufacturing/production of specific stack components. This study demonstrates that mass production can give a concrete perspective for the large-scale diffusion of DMFCs as APUs. The results show that the cost derived for the DMFC stack is relatively close to that of competing technologies and that the introduction of innovative approaches can result in further cost savings.

  16. Optimal Pricing and Advertising Policies for New Product Oligopoly Models

    OpenAIRE

    Gerald L. Thompson; Jinn-Tsair Teng

    1984-01-01

    In this paper our previous work on monopoly and oligopoly new product models is extended by the addition of pricing as well as advertising control variables. These models contain Bass's demand growth model, and the Vidale-Wolfe and Ozga advertising models, as well as the production learning curve model and an exponential demand function. The problem of characterizing an optimal pricing and advertising policy over time is an important question in the field of marketing as well as in the areas ...

  17. Human bone marrow mesenchymal stem cells induce collagen production and tongue cancer invasion.

    Directory of Open Access Journals (Sweden)

    Sirpa Salo

    Full Text Available Tumor microenvironment (TME is an active player in carcinogenesis and changes in its composition modify cancer growth. Carcinoma-associated fibroblasts, bone marrow-derived multipotent mesenchymal stem cells (BMMSCs, and inflammatory cells can all affect the composition of TME leading to changes in proliferation, invasion and metastasis formation of carcinoma cells. In this study, we confirmed an interaction between BMMSCs and oral tongue squamous cell carcinoma (OTSCC cells by analyzing the invasion progression and gene expression pattern. In a 3-dimensional myoma organotypic invasion model the presence of BMMSCs inhibited the proliferation but increased the invasion of OTSCC cells. Furthermore, the signals originating from OTSCC cells up-regulated the expression of inflammatory chemokines by BMMSCs, whereas BMMSC products induced the expression of known invasion linked molecules by carcinoma cells. Particularly, after the cell-cell interactions, the chemokine CCL5 was abundantly secreted from BMMSCs and a function blocking antibody against CCL5 inhibited BMMSC enhanced cancer invasion area. However, CCL5 blocking antibody did not inhibit the depth of invasion. Additionally, after exposure to BMMSCs, the expression of type I collagen mRNA in OTSCC cells was markedly up-regulated. Interestingly, also high expression of type I collagen N-terminal propeptide (PINP in vivo correlated with the cancer-specific mortality of OTSCC patients, whereas there was no association between cancer tissue CCL5 levels and the clinical parameters. In conclusion, our results suggest that the interaction between BMMSC and carcinoma cells induce cytokine and matrix molecule expression, of which high level of type I collagen production correlates with the prognosis of OTSCC patients.

  18. Concurrent engineering and product models in seafood companies

    DEFF Research Database (Denmark)

    Jonsdottir, Stella; Vesterager, Johan; Børresen, Torger

    1998-01-01

    Concurrent Engineering (CE) can provide an improved approach to product development for extending the lines of seafood products. Information technology (IT) support tools based on product models can provide an integrated and simultaneous approach for specifying new recipes. The seafood industry can...... benefit from the CE approach which can support product developers to provide concurrent specifications for raw materials, ingredients, packaging, and production methods. The approach involves the use of product models from which line extensions are more easily generated than by use of customary stepwise...

  19. From Commodity Production to Sign Production: A Triple Triangle Model for Marx's Semiotics and Peirce's Economics.

    Science.gov (United States)

    Kim, Joohoan

    Using the viewpoint of semiotics, this paper "re-reads" Karl Marx's labor theory of value and suggests a "triple triangle" model for commodity production and shows how this model could be a model for semiosis in general. The paper argues that there are three advantages to considering homogeneity of the sign production and the…

  20. Modeling the Potential Effects of New Tobacco Products and Policies: A Dynamic Population Model for Multiple Product Use and Harm

    Science.gov (United States)

    Vugrin, Eric D.; Rostron, Brian L.; Verzi, Stephen J.; Brodsky, Nancy S.; Brown, Theresa J.; Choiniere, Conrad J.; Coleman, Blair N.; Paredes, Antonio; Apelberg, Benjamin J.

    2015-01-01

    Background Recent declines in US cigarette smoking prevalence have coincided with increases in use of other tobacco products. Multiple product tobacco models can help assess the population health impacts associated with use of a wide range of tobacco products. Methods and Findings We present a multi-state, dynamical systems population structure model that can be used to assess the effects of tobacco product use behaviors on population health. The model incorporates transition behaviors, such as initiation, cessation, switching, and dual use, related to the use of multiple products. The model tracks product use prevalence and mortality attributable to tobacco use for the overall population and by sex and age group. The model can also be used to estimate differences in these outcomes between scenarios by varying input parameter values. We demonstrate model capabilities by projecting future cigarette smoking prevalence and smoking-attributable mortality and then simulating the effects of introduction of a hypothetical new lower-risk tobacco product under a variety of assumptions about product use. Sensitivity analyses were conducted to examine the range of population impacts that could occur due to differences in input values for product use and risk. We demonstrate that potential benefits from cigarette smokers switching to the lower-risk product can be offset over time through increased initiation of this product. Model results show that population health benefits are particularly sensitive to product risks and initiation, switching, and dual use behaviors. Conclusion Our model incorporates the variety of tobacco use behaviors and risks that occur with multiple products. As such, it can evaluate the population health impacts associated with the introduction of new tobacco products or policies that may result in product switching or dual use. Further model development will include refinement of data inputs for non-cigarette tobacco products and inclusion of health

  1. Natural products induce a G protein-mediated calcium pathway activating p53 in cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Ginkel, Paul R. van; Yan, Michael B. [UW Carbone Cancer Center, University of Wisconsin, Madison, WI 53792 (United States); Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI 53792 (United States); Bhattacharya, Saswati [UW Carbone Cancer Center, University of Wisconsin, Madison, WI 53792 (United States); Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI 53792 (United States); Department of Pediatrics, University of Wisconsin, Madison, WI 53792 (United States); Polans, Arthur S., E-mail: aspolans@wisc.edu [UW Carbone Cancer Center, University of Wisconsin, Madison, WI 53792 (United States); Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI 53792 (United States); Kenealey, Jason D. [UW Carbone Cancer Center, University of Wisconsin, Madison, WI 53792 (United States); Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, WI 53792 (United States); Department of Nutrition, Dietetics and Food Science, Brigham Young University, Provo, UT 84602 (United States)

    2015-11-01

    Paclitaxel, etoposide, vincristine and doxorubicin are examples of natural products being used as chemotherapeutics but with adverse side effects that limit their therapeutic window. Natural products derived from plants and having low toxicity, such as quercetin, resveratrol, epigallocatechin gallate and piceatannol, have been shown to inhibit tumor cell growth both in vitro and in pre-clinical models of cancer, but their mechanisms of action have not been fully elucidated, thus restricting their use as prototypes for developing synthetic analogs with improved anti-cancer properties. We and others have demonstrated that one of the earliest and consistent events upon exposure of tumor cells to these less toxic natural products is a rise in cytoplasmic calcium, activating several pro-apoptotic pathways. We describe here a G protein/inositol 1,4,5-trisphosphate pathway (InsP3) in MDA-MB-231 human breast cancer cells that mediates between these less toxic natural products and the release of calcium from the endoplasmic reticulum. Further, we demonstrate that this elevation of intracellular calcium modulates p53 activity and the subsequent transcription of several pro-apoptotic genes encoding PIG8, CD95, PIDD, TP53INP, RRM2B, Noxa, p21 and PUMA. We conclude from our findings that less toxic natural products likely bind to a G protein coupled receptor that activates a G protein-mediated and calcium-dependent pathway resulting selectively in tumor cell death. - Highlights: • Natural products having low toxicity increase cytoplasmic calcium in cancer cells. • A G-protein/IP{sub 3} pathway mediates the release of calcium from the ER. • The elevation of intracellular calcium modulates p53 activity. • p53 and other Ca{sup 2+}-dependent pro-apoptotic pathways inhibit cancer cell growth.

  2. Natural products induce a G protein-mediated calcium pathway activating p53 in cancer cells

    International Nuclear Information System (INIS)

    Ginkel, Paul R. van; Yan, Michael B.; Bhattacharya, Saswati; Polans, Arthur S.; Kenealey, Jason D.

    2015-01-01

    Paclitaxel, etoposide, vincristine and doxorubicin are examples of natural products being used as chemotherapeutics but with adverse side effects that limit their therapeutic window. Natural products derived from plants and having low toxicity, such as quercetin, resveratrol, epigallocatechin gallate and piceatannol, have been shown to inhibit tumor cell growth both in vitro and in pre-clinical models of cancer, but their mechanisms of action have not been fully elucidated, thus restricting their use as prototypes for developing synthetic analogs with improved anti-cancer properties. We and others have demonstrated that one of the earliest and consistent events upon exposure of tumor cells to these less toxic natural products is a rise in cytoplasmic calcium, activating several pro-apoptotic pathways. We describe here a G protein/inositol 1,4,5-trisphosphate pathway (InsP3) in MDA-MB-231 human breast cancer cells that mediates between these less toxic natural products and the release of calcium from the endoplasmic reticulum. Further, we demonstrate that this elevation of intracellular calcium modulates p53 activity and the subsequent transcription of several pro-apoptotic genes encoding PIG8, CD95, PIDD, TP53INP, RRM2B, Noxa, p21 and PUMA. We conclude from our findings that less toxic natural products likely bind to a G protein coupled receptor that activates a G protein-mediated and calcium-dependent pathway resulting selectively in tumor cell death. - Highlights: • Natural products having low toxicity increase cytoplasmic calcium in cancer cells. • A G-protein/IP 3 pathway mediates the release of calcium from the ER. • The elevation of intracellular calcium modulates p53 activity. • p53 and other Ca 2+ -dependent pro-apoptotic pathways inhibit cancer cell growth.

  3. Durability of solid oxide electrolysis cells for hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Hauch, A.; Hoejgaard Jensen, S.; Dalgaard Ebbesen, S.

    2007-05-15

    In the perspective of the increasing interest in renewable energy and hydrogen economy, the reversible solid oxide cells (SOCs) is a promising technology as it has the potential of providing efficient and cost effective hydrogen production by high temperature electrolysis of steam (HTES). Furthermore development of such electrolysis cells can gain from the results obtained within the R and D of SOFCs. For solid oxide electrolysis cells (SOEC) to become interesting from a technological point of view, cells that are reproducible, high performing and long-term stable need to be developed. In this paper we address some of the perspectives of the SOEC technology i.e. issues such as a potential H2 production price as low as 0.71 US dollar/kg H{sub 2} using SOECs for HTES; is there a possible market for the electrolysers? and what R and D steps are needed for the realisation of the SOEC technology? In the experimental part we present electrolysis test results on SOCs that have been optimized for fuel cell operation but applied for HTES. The SOCs are produced on a pre-pilot scale at Risoe National Laboratory. These cells have been shown to have excellent initial electrolysis performance, but the durability of such electrolysis cells are not optimal and examples of results from SOEC tests over several hundreds of hours are given here. The long-term tests have been run at current densities of -0.5 A/cm{sup 2} and -1 A/cm{sup 2}, temperatures of 850 deg. C and 950 deg. C and p(H{sub 2}O)/p(H{sub 2}) of 0.5/0.5 and 0.9/0.1. Long-term degradation rates are shown to be up to 5 times higher for SOECs compared to similar SOFC testing. Furthermore, hydrogen and synthetic fuel production prices are calculated using the experimental results from long-term electrolysis test as input and a short outlook for the future work on SOECs will be given as well. (au)

  4. Development of a yeast cell factory for production of aromatic products

    DEFF Research Database (Denmark)

    Rodriguez Prado, Edith Angelica; Kildegaard, Kanchana Rueksomtawin; Li, Mingji

    2014-01-01

    There is much interest in aromatic chemicals in the chemical industry as these can be used for production of dyes, anti-oxidants, nutraceuticals and food ingredients. Yeast is a widely used cell factory and it is particularly well suited for production of aromatic chemicals via complex biosynthetic...... routes involving P450 enzymes. In Saccharomyces cerevisiae the fluxes towards aromatic acids (L-tryptophan, L-tyrosine and L-phenylalanine) are strictly controlled on transcriptional and kinetic levels and therefore are difficult to manipulate. We engineered S. cerevisiae for increased production...... of aromatic compounds by eliminating degradation, up-regulating the key enzyme encoding genes, and removing feed-back inhibition in the pathway. In order to test the strain performance we overexpressed heterologous pathway for coumaric acid production. We obtained 4-fold higher concentrations of coumaric acid...

  5. An economic production model for time dependent demand with rework and multiple production setups

    Directory of Open Access Journals (Sweden)

    S.R. Singh

    2014-04-01

    Full Text Available In this paper, we present a model for time dependent demand with multiple productions and rework setups. Production is demand dependent and greater than the demand rate. Production facility produces items in m production setups and one rework setup (m, 1 policy. The major reason of reverse logistic and green supply chain is rework, so it reduces the cost of production and other ecological problems. Most of the researchers developed a rework model without deteriorating items. A numerical example and sensitivity analysis is shown to describe the model.

  6. A model to explain human voice production

    Science.gov (United States)

    Vilas Bôas, C. S. N.; Gobara, S. T.

    2018-05-01

    This article presents a device constructed with low-cost material to demonstrate and explain voice production. It also provides a contextualized, interdisciplinary approach to introduce the study of sound waves.

  7. Multi products single machine economic production quantity model with multiple batch size

    Directory of Open Access Journals (Sweden)

    Ata Allah Taleizadeh

    2011-04-01

    Full Text Available In this paper, a multi products single machine economic order quantity model with discrete delivery is developed. A unique cycle length is considered for all produced items with an assumption that all products are manufactured on a single machine with a limited capacity. The proposed model considers different items such as production, setup, holding, and transportation costs. The resulted model is formulated as a mixed integer nonlinear programming model. Harmony search algorithm, extended cutting plane and particle swarm optimization methods are used to solve the proposed model. Two numerical examples are used to analyze and to evaluate the performance of the proposed model.

  8. Interleukin-2 production by human leukemia cell lines of pre-B cell origin

    International Nuclear Information System (INIS)

    Holan, V.; Minowada, J.

    1993-01-01

    Cells of 7 tested human leukemia cell lines of pre-B cell origin (as characterized by immunophenotyping and by the expression of cytoplasmic micro chains, but not by surface immunoglobulins) produced after stimulation with bacterial lipopolysaccharide (LPS) or phorbol myristate acetate (PMA) a lymphokine activity which supported the growth of the interleukin-2 (IL-2)-dependent CTLL-2 cell line. Three pieces of evidence indicate that the secreted lymphokine was functionally and antigenically very similar, if not identical, to human IL-2: (1) The lymphokine supported the growth of murine IL-2-dependent CTLL-2 cells, which did not respond to human lymphokines other than IL-2, but it did not stimulate the growth of murine IL-3-dependent FDC-P2 cells, (2) the biological activity of the lymphokine was was inhibited by monoclonal antibody (mAb) anti-human-IL-2, and (3) the proliferation of IL-2-dependent cells in the presence of the active materials was completely inhibited by the inclusion of the anti-mouse-IL-2 receptor (IL-2R) mAb. Since leukemia cells of immature B-cell origin also synthesize IL-2R, the human pre-B cell leukemias could represent another type of hematological malignancy where the autocrine processes of IL-2 production and utilization are involved in the expansion of the disease. (author)

  9. Economic production quantity models for imperfect product and service with rework

    OpenAIRE

    Tai, Allen H.

    2012-01-01

    When imperfect quality products are produced in a production process, rework may be performed to make them become serviceable. In an inventory system, items may deteriorate. Selling deteriorated items to customers will create negative impact on corporate image. In this paper, two economic production quantity (EPQ) models are proposed for deteriorating items with rework process. A single production-rework plant system and a system consists of $n$ production plants and one rework plant are cons...

  10. T cell subsets related with a sex difference in IL-5 production.

    Science.gov (United States)

    Okuyama, Kaori; Hamanaka, Yuka; Kawano, Tasuku; Ohkawara, Yuichi; Takayanagi, Motoaki; Kikuchi, Toshiaki; Ohno, Isao

    2011-01-01

    Before puberty, the prevalence and severity of asthma are higher in boys than in girls, but this pattern is reversed after puberty. The underlying mechanisms of these gender differences in asthma are not fully understood. Using murine models of allergic asthma, a sex difference in Th2 cytokine production has been suggested to contribute to the gender differences in asthma. Therefore, we determined which subsets of T cells are involved in the sex difference in Th2 cytokine production. Splenocytes from wild-type mice and CD4+ T cell-, CD8+ T cell-, and iNKT cell-deficient mice were stimulated with anti-CD3/CD28 antibodies for 3 days, and the concentrations of IL-4, IL-5, IL-13, and IFN-γ in the cultures were measured by ELISA. IL-5, but not IL-4 and IL-13, concentrations in culture derived from female wild-type mice were significantly higher than those in male wild-type mice. The sex difference in IL-5 concentrations was not observed in the cultures of splenocytes from CD4+ and CD8+ T cell-deficient mice. The disappearance of the sex differences in CD4+ and CD8+ T cell-deficient mice was attributable to a decrease in IL-5 concentration in female mice and an increase in IL-5 concentration in male mice. In iNKT cell-deficient mice, the sex difference was still observed. There was no significant difference between the sexes in any type of mice with respect to IFN-γ production. There was a sex difference in IL-5 production by splenocytes stimulated by TCR activation. The difference might be attributable to sex differences in CD4+ and CD8+ T cell functions. Copyright © 2011 S. Karger AG, Basel.

  11. Modeling of Agile Intelligent Manufacturing-oriented Production Scheduling System

    Institute of Scientific and Technical Information of China (English)

    Zhong-Qi Sheng; Chang-Ping Tang; Ci-Xing Lv

    2010-01-01

    Agile intelligent manufacturing is one of the new manufacturing paradigms that adapt to the fierce globalizing market competition and meet the survival needs of the enterprises, in which the management and control of the production system have surpassed the scope of individual enterprise and embodied some new features including complexity, dynamicity, distributivity, and compatibility. The agile intelligent manufacturing paradigm calls for a production scheduling system that can support the cooperation among various production sectors, the distribution of various resources to achieve rational organization, scheduling and management of production activities. This paper uses multi-agents technology to build an agile intelligent manufacturing-oriented production scheduling system. Using the hybrid modeling method, the resources and functions of production system are encapsulated, and the agent-based production system model is established. A production scheduling-oriented multi-agents architecture is constructed and a multi-agents reference model is given in this paper.

  12. Advances in in-situ product recovery (ISPR) in whole cell biotechnology during the last decade.

    Science.gov (United States)

    Van Hecke, Wouter; Kaur, Guneet; De Wever, Heleen

    2014-11-15

    The review presents the state-of-the-art in the applications of in-situ product recovery (ISPR) in whole-cell biotechnology over the last 10years. It summarizes various ISPR-integrated fermentation processes for the production of a wide spectrum of bio-based products. A critical assessment of the performance of various ISPR concepts with respect to the degree of product enrichment, improved productivity, reduced process flows and increased yields is provided. Requirements to allow a successful industrial implementation of ISPR are also discussed. Finally, supporting technologies such as online monitoring, mathematical modeling and use of recombinant microorganisms with ISPR are presented. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Repair-misrepair model of cell survival

    International Nuclear Information System (INIS)

    Tobias, C.A.; Blakely, E.A.; Ngo, F.Q.H.

    1980-01-01

    During the last three years a new model, the repair-misrepair model (RMR) has been proposed, to interpret radiobiological experiments with heavy ions. In using the RMR model it became apparent that some of its features are suitable for handling the effects produced by a variety of environmental agents in addition to ionizing radiation. Two separate sequences of events are assumed to take place in an irradiated cell. The first sequence begins with an initial energy transfer consisting of ionizations and excitations, culminating via fast secondary physical and chemical processes in established macromolecular lesions in essential cell structures. The second sequence contains the responses of the cell to the lesions and consists of the processes of recognition and molecular repair. In normal cells there exists one repair process or at most a few enzymatic repair processes for each essential macromolecular lesion. The enzymatic repair processes may last for hours and minutes, and can be separated in time from the initial physicochemical and later genetic phases

  14. Microbial reverse-electrodialysis chemical-production cell for acid and alkali production

    KAUST Repository

    Zhu, Xiuping

    2013-06-01

    A new type of bioelectrochemical system, called a microbial reverse-electrodialysis chemical-production cell (MRCC), was developed to produce acid and alkali using energy derived from organic matter (acetate) and salinity gradients (NaCl solutions representative of seawater and river water). A bipolar membrane (BPM) was placed next to the anode to prevent Cl- contamination and acidification of the anolyte, and to produce protons for HCl recovery. A 5-cell paired reverse-electrodialysis (RED) stack provided the electrical energy required to overcome the BPM over-potential (0.3-0.6 V), making the overall process spontaneous. The MRCC reactor produced electricity (908 mW/m2) as well as concentrated acidic and alkaline solutions, and therefore did not require an external power supply. After a fed-batch cycle, the pHs of the chemical product solutions were 1.65 ± 0.04 and 11.98 ± 0.10, due to the production of 1.35 ± 0.13 mmol of acid, and 0.59 ± 0.14 mmol of alkali. The acid- and alkali-production efficiencies based on generated current were 58 ± 3% and 25 ± 3%. These results demonstrated proof-of-concept acid and alkali production using only renewable energy sources. © 2013 Elsevier B.V.

  15. Extracellular ATP drives breast cancer cell migration and metastasis via S100A4 production by cancer cells and fibroblasts.

    Science.gov (United States)

    Liu, Ying; Geng, Yue-Hang; Yang, Hui; Yang, Han; Zhou, Yan-Ting; Zhang, Hong-Quan; Tian, Xin-Xia; Fang, Wei-Gang

    2018-05-04

    Our previous work has demonstrated that extracellular ATP is an important pro-invasive factor, and in this study, we tapped into a possible mechanism involved. We discovered that ATP could upregulate both the intracellular expression and secretion of S100A4 in breast cancer cells and fibroblasts. Apart from stimulating breast cancer cell motility via intracellular S100A4, ATP enhanced the ability of breast cancer cells to transform fibroblasts into cancer-associated fibroblast (CAF)-like cells, which in turn secreted S100A4 to further promote cancer cell motility. Both apyrase and niclosamide treatments could inhibit metastasis of inoculated tumors to lung, liver and kidney in mice model, and CAFs from these treated tumors exhibited weakened migration-stimulating capacity for breast cancer cells. Collectively, our data indicate that extracellular ATP promotes the interactions between breast cancer cells and fibroblasts, which work collaboratively via production of S100A4 to exacerbate breast cancer metastasis. Copyright © 2018. Published by Elsevier B.V.

  16. Donor lung derived myeloid and plasmacytoid dendritic cells differentially regulate T cell proliferation and cytokine production

    Directory of Open Access Journals (Sweden)

    Benson Heather L

    2012-03-01

    Full Text Available Abstract Background Direct allorecognition, i.e., donor lung-derived dendritic cells (DCs stimulating recipient-derived T lymphocytes, is believed to be the key mechanism of lung allograft rejection. Myeloid (cDCs and plasmacytoid (pDCs are believed to have differential effects on T cell activation. However, the roles of each DC type on T cell activation and rejection pathology post lung transplantation are unknown. Methods Using transgenic mice and antibody depletion techniques, either or both cell types were depleted in lungs of donor BALB/c mice (H-2d prior to transplanting into C57BL/6 mice (H-2b, followed by an assessment of rejection pathology, and pDC or cDC-induced proliferation and cytokine production in C57BL/6-derived mediastinal lymph node T cells (CD3+. Results Depleting either DC type had modest effect on rejection pathology and T cell proliferation. In contrast, T cells from mice that received grafts depleted of both DCs did not proliferate and this was associated with significantly reduced acute rejection scores compared to all other groups. cDCs were potent inducers of IFNγ, whereas both cDCs and pDCs induced IL-10. Both cell types had variable effects on IL-17A production. Conclusion Collectively, the data show that direct allorecognition by donor lung pDCs and cDCs have differential effects on T cell proliferation and cytokine production. Depletion of both donor lung cDC and pDC could prevent the severity of acute rejection episodes.

  17. Modelling and analysis of solar cell efficiency distributions

    Science.gov (United States)

    Wasmer, Sven; Greulich, Johannes

    2017-08-01

    We present an approach to model the distribution of solar cell efficiencies achieved in production lines based on numerical simulations, metamodeling and Monte Carlo simulations. We validate our methodology using the example of an industrial feasible p-type multicrystalline silicon “passivated emitter and rear cell” process. Applying the metamodel, we investigate the impact of each input parameter on the distribution of cell efficiencies in a variance-based sensitivity analysis, identifying the parameters and processes that need to be improved and controlled most accurately. We show that if these could be optimized, the mean cell efficiencies of our examined cell process would increase from 17.62% ± 0.41% to 18.48% ± 0.09%. As the method relies on advanced characterization and simulation techniques, we furthermore introduce a simplification that enhances applicability by only requiring two common measurements of finished cells. The presented approaches can be especially helpful for ramping-up production, but can also be applied to enhance established manufacturing.

  18. Amphiregulin mediates hCG-induced StAR expression and progesterone production in human granulosa cells

    OpenAIRE

    Fang, Lanlan; Yu, Yiping; Zhang, Ruizhe; He, Jingyan; Sun, Ying-Pu

    2016-01-01

    Progesterone plays critical roles in maintaining a successful pregnancy at the early embryonic stage. Human chorionic gonadotropin (hCG) rapidly induces amphiregulin (AREG) expression. However, it remains unknown whether AREG mediates hCG-induced progesterone production. Thus, the objective of this study was to investigate the role of AREG in hCG-induced progesterone production and the underlying molecular mechanism in human granulosa cells; primary cells were used as the experimental model. ...

  19. A single product perishing inventory model with demand interaction

    African Journals Online (AJOL)

    The paper describes a single perishing product inventory model in which ... continuous review inventory models have been studied recently by Yadavalli et al ...... stochastic inventory system with lost sales, Stochastic Analysis and Applications ...

  20. Mutations That Alter the Bacterial Cell Envelope Increase Lipid Production

    Energy Technology Data Exchange (ETDEWEB)

    Lemmer, Kimberly C.; Zhang, Weiping; Langer, Samantha J.; Dohnalkova, Alice; Hu, Dehong; Lemke, Rachelle A.; Piotrowski, Jeff S.; Orr, Galya; Noguera, Daniel R.; Donohue, Timothy J.

    2017-05-23

    ABSTRACT

    Lipids from microbes offer a promising source of renewable alternatives to petroleum-derived compounds. In particular, oleaginous microbes are of interest because they accumulate a large fraction of their biomass as lipids. In this study, we analyzed genetic changes that alter lipid accumulation inRhodobacter sphaeroides. By screening anR. sphaeroidesTn5mutant library for insertions that increased fatty acid content, we identified 10 high-lipid (HL) mutants for further characterization. These HL mutants exhibited increased sensitivity to drugs that target the bacterial cell envelope and changes in shape, and some had the ability to secrete lipids, with two HL mutants accumulating ~60% of their total lipids extracellularly. When one of the highest-lipid-secreting strains was grown in a fed-batch bioreactor, its lipid content was comparable to that of oleaginous microbes, with the majority of the lipids secreted into the medium. Based on the properties of these HL mutants, we conclude that alterations of the cell envelope are a previously unreported approach to increase microbial lipid production. We also propose that this approach may be combined with knowledge about biosynthetic pathways, in this or other microbes, to increase production of lipids and other chemicals.

    IMPORTANCEThis paper reports on experiments to understand how to increase microbial lipid production. Microbial lipids are often cited as one renewable replacement for petroleum-based fuels and chemicals, but strategies to increase the yield of these compounds are needed to achieve this goal. While lipid biosynthesis is often well understood, increasing yields of these compounds to industrially relevant levels is a challenge, especially since genetic, synthetic biology, or engineering approaches are not feasible in many microbes. We show that altering the bacterial cell envelope can be used to increase

  1. Byproduct mineral commodities used for the production of photovoltaic cells

    Science.gov (United States)

    Bleiwas, Donald I.

    2010-01-01

    Rising fossil fuel costs, environmental concerns relating to global climate change, and Government policy to signifcantly increase our Nation's energy independence have placed greater emphasis on the generation of electricity from renewable sources, such as the Sun (light and heat), water, and wind, which for all intents and purposes are inexhaustible resources. Although the total amount of electricity generated from the direct conversion of sunlight through photovoltaic cells is relatively small compared with that from other forms of renewable energy, the rate of growth in the sector is signifcant. The total value of energy of photovoltaic cells produced worldwide increased to nearly 7 gigawatts (GW) in 2008 from 45 megawatts (MW) in 1990, a compound annual growth rate of about 30 percent. In the United States, manufacturing of photovoltaic cells has grown exponentially to about 480 MW in 2008, accounting for 6 percent of world production, from less than 10 MW of photovoltaic capacity in 1990 (Benner, 2007; U.S. Department of Energy, Energy Information Administration, 2010), a compound annual growth rate of approxi-mately 23 percent. A production capacity of 1 GW of electricity [or 8,760 gigawatthours1 (GWh)] is equivalent to the annual electricity requirements for roughly 800,000 average households in the United States (U.S. Department of Energy, Energy Information Administration, 2010). This estimate does not include losses of electricity, such as during transmission through power lines.

  2. Parallel Development of Products and New Business Models

    DEFF Research Database (Denmark)

    Lund, Morten; Hansen, Poul H. Kyvsgård

    2014-01-01

    The perception of product development and the practical execution of product development in professional organizations have undergone dramatic changes in recent years. Many of these chances relate to introduction of broader and more cross-disciplinary views that involves new organizational functi...... and innovation management the 4th generation models are increasingly including the concept business models and business model innovation....... functions and new concepts. These chances can be captured in various generations of practice. This paper will discuss the recent development of 3rd generation product development process models and the emergence of a 4th generation. While the 3rd generation models included the concept of innovation...

  3. Minimal RED Cell Pairs Markedly Improve Electrode Kinetics and Power Production in Microbial Reverse Electrodialysis Cells

    KAUST Repository

    Cusick, Roland D.

    2013-12-17

    Power production from microbial reverse electrodialysis cell (MRC) electrodes is substantially improved compared to microbial fuel cells (MFCs) by using ammonium bicarbonate (AmB) solutions in multiple RED cell pair stacks and the cathode chamber. Reducing the number of RED membranes pairs while maintaining enhanced electrode performance could help to reduce capital costs. We show here that using only a single RED cell pair (CP), created by operating the cathode in concentrated AmB, dramatically increased power production normalized to cathode area from both acetate (Acetate: from 0.9 to 3.1 W/m 2-cat) and wastewater (WW: 0.3 to 1.7 W/m2), by reducing solution and charge transfer resistances at the cathode. A second RED cell pair increased RED stack potential and reduced anode charge transfer resistance, further increasing power production (Acetate: 4.2 W/m2; WW: 1.9 W/m2). By maintaining near optimal electrode power production with fewer membranes, power densities normalized to total membrane area for the 1-CP (Acetate: 3.1 W/m2-mem; WW: 1.7 W/m2) and 2-CP (Acetate: 1.3 W/m2-mem; WW: 0.6 W/m2) reactors were much higher than previous MRCs (0.3-0.5 W/m2-mem with acetate). While operating at peak power, the rate of wastewater COD removal, normalized to reactor volume, was 30-50 times higher in 1-CP and 2-CP MRCs than that in a single chamber MFC. These findings show that even a single cell pair AmB RED stack can significantly enhance electrical power production and wastewater treatment. © 2013 American Chemical Society.

  4. Minimal RED Cell Pairs Markedly Improve Electrode Kinetics and Power Production in Microbial Reverse Electrodialysis Cells

    KAUST Repository

    Cusick, Roland D.; Hatzell, Marta; Zhang, Fang; Logan, Bruce E.

    2013-01-01

    Power production from microbial reverse electrodialysis cell (MRC) electrodes is substantially improved compared to microbial fuel cells (MFCs) by using ammonium bicarbonate (AmB) solutions in multiple RED cell pair stacks and the cathode chamber. Reducing the number of RED membranes pairs while maintaining enhanced electrode performance could help to reduce capital costs. We show here that using only a single RED cell pair (CP), created by operating the cathode in concentrated AmB, dramatically increased power production normalized to cathode area from both acetate (Acetate: from 0.9 to 3.1 W/m 2-cat) and wastewater (WW: 0.3 to 1.7 W/m2), by reducing solution and charge transfer resistances at the cathode. A second RED cell pair increased RED stack potential and reduced anode charge transfer resistance, further increasing power production (Acetate: 4.2 W/m2; WW: 1.9 W/m2). By maintaining near optimal electrode power production with fewer membranes, power densities normalized to total membrane area for the 1-CP (Acetate: 3.1 W/m2-mem; WW: 1.7 W/m2) and 2-CP (Acetate: 1.3 W/m2-mem; WW: 0.6 W/m2) reactors were much higher than previous MRCs (0.3-0.5 W/m2-mem with acetate). While operating at peak power, the rate of wastewater COD removal, normalized to reactor volume, was 30-50 times higher in 1-CP and 2-CP MRCs than that in a single chamber MFC. These findings show that even a single cell pair AmB RED stack can significantly enhance electrical power production and wastewater treatment. © 2013 American Chemical Society.

  5. Continuous Ethanol Production Using Immobilized-Cell/Enzyme Biocatalysts in Fluidized-Bed Bioreactor (FBR)

    Energy Technology Data Exchange (ETDEWEB)

    Nghiem, NP

    2003-11-16

    The immobilized-cell fluidized-bed bioreactor (FBR) was developed at Oak Ridge National Laboratory (ORNL). Previous studies at ORNL using immobilized Zymomonas mobilis in FBR at both laboratory and demonstration scale (4-in-ID by 20-ft-tall) have shown that the system was more than 50 times as productive as industrial benchmarks (batch and fed-batch free cell fermentations for ethanol production from glucose). Economic analysis showed that a continuous process employing the FBR technology to produce ethanol from corn-derived glucose would offer savings of three to six cents per gallon of ethanol compared to a typical batch process. The application of the FBR technology for ethanol production was extended to investigate more complex feedstocks, which included starch and lignocellulosic-derived mixed sugars. Economic analysis and mathematical modeling of the reactor were included in the investigation. This report summarizes the results of these extensive studies.

  6. Engineering CHO cells with an oncogenic KIT improves cells growth, resilience to stress, and productivity.

    Science.gov (United States)

    Mahameed, Mohamed; Tirosh, Boaz

    2017-11-01

    An optimized biomanufacturing process in mammalian cells is contingent on the ability of the producing cells to reach high viable cell densities. In addition, at the peak of growth, cells need to continue producing the biological entity at a consistent quality. Thus, engineering cells with robust growth performance and resilience to variable stress conditions is highly desirable. The tyrosine kinase receptor, KIT, plays a key role in cell differentiation and the survival of several immune cell types. Its oncogenic mutant, D816V, endows cells with high proliferation capacity, and resistance to kinase inhibitors. Importantly, this onco-KIT mutant when introduced into various cell types is arrested in the endoplasmic reticulum in a constitutively active form. Here, we investigated the effect of oncogenic D816V KIT on the performance of CHO-K1 cells under conventional tissue culture growth settings and when adapted, to shaking conditions. The onco-KIT promoted global protein synthesis, elevated the expression of a secretable transgene, enhanced proliferation, and improved the overall titers of a model glycoprotein. Moreover, the expression of the onco-KIT endowed the cells with a remarkable resistance to various stress conditions. Our data suggest that the introduction of onco-KIT can serve as a strategy for improving glycoprotein biomanufacturing. Biotechnol. Bioeng. 2017;114: 2560-2570. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  7. Predictive modeling of biomass production by Chlorella vulgaris in a draft-tube airlift photobioreactor

    Directory of Open Access Journals (Sweden)

    Mohsen Mansouri

    2017-04-01

    Full Text Available The objective of this study was to investigate the growth rate of Chlorella vulgaris for CO2 biofixation and biomass production. Six mathematical growth models (Logistic, Gompertz, modified Gompertz, Baranyi, Morgan and Richards were used to evaluate the biomass productivity in continuous processes and to predict the following parameters of cell growth: lag phase duration (λ, maximum specific growth rate (μmax, and maximum cell concentration (Xmax. The low root-mean-square error (RMSE and high regression coefficients (R2 indicated that the models employed were well fitted to the experiment data and it could be regarded as enough to describe biomass production. Using statistical and physiological significance criteria, the Baranyi model was considered the most appropriate for quantifying biomass growth. The biological variables of this model are as follows: μmax=0.0309 h−1, λ=100 h, and Xmax=1.82 g/L.

  8. Colon cancer stem cells dictate tumor growth and resist cell death by production of interleukin-4.

    Science.gov (United States)

    Todaro, Matilde; Alea, Mileidys Perez; Di Stefano, Anna B; Cammareri, Patrizia; Vermeulen, Louis; Iovino, Flora; Tripodo, Claudio; Russo, Antonio; Gulotta, Gaspare; Medema, Jan Paul; Stassi, Giorgio

    2007-10-11

    A novel paradigm in tumor biology suggests that cancer growth is driven by stem-like cells within a tumor. Here, we describe the identification and characterization of such cells from colon carcinomas using the stem cell marker CD133 that accounts around 2% of the cells in human colon cancer. The CD133(+) cells grow in vitro as undifferentiated tumor spheroids, and they are both necessary and sufficient to initiate tumor growth in immunodeficient mice. Xenografts resemble the original human tumor maintaining the rare subpopulation of tumorigenic CD133(+) cells. Further analysis revealed that the CD133(+) cells produce and utilize IL-4 to protect themselves from apoptosis. Consistently, treatment with IL-4Ralpha antagonist or anti-IL-4 neutralizing antibody strongly enhances the antitumor efficacy of standard chemotherapeutic drugs through selective sensitization of CD133(+) cells. Our data suggest that colon tumor growth is dictated by stem-like cells that are treatment resistant due to the autocrine production of IL-4.

  9. Models for estimating photosynthesis parameters from in situ production profiles

    Science.gov (United States)

    Kovač, Žarko; Platt, Trevor; Sathyendranath, Shubha; Antunović, Suzana

    2017-12-01

    The rate of carbon assimilation in phytoplankton primary production models is mathematically prescribed with photosynthesis irradiance functions, which convert a light flux (energy) into a material flux (carbon). Information on this rate is contained in photosynthesis parameters: the initial slope and the assimilation number. The exactness of parameter values is crucial for precise calculation of primary production. Here we use a model of the daily production profile based on a suite of photosynthesis irradiance functions and extract photosynthesis parameters from in situ measured daily production profiles at the Hawaii Ocean Time-series station Aloha. For each function we recover parameter values, establish parameter distributions and quantify model skill. We observe that the choice of the photosynthesis irradiance function to estimate the photosynthesis parameters affects the magnitudes of parameter values as recovered from in situ profiles. We also tackle the problem of parameter exchange amongst the models and the effect it has on model performance. All models displayed little or no bias prior to parameter exchange, but significant bias following parameter exchange. The best model performance resulted from using optimal parameter values. Model formulation was extended further by accounting for spectral effects and deriving a spectral analytical solution for the daily production profile. The daily production profile was also formulated with time dependent growing biomass governed by a growth equation. The work on parameter recovery was further extended by exploring how to extract photosynthesis parameters from information on watercolumn production. It was demonstrated how to estimate parameter values based on a linearization of the full analytical solution for normalized watercolumn production and from the solution itself, without linearization. The paper complements previous works on photosynthesis irradiance models by analysing the skill and consistency of

  10. Applying linear programming model to aggregate production planning of coated peanut products

    Science.gov (United States)

    Rohmah, W. G.; Purwaningsih, I.; Santoso, EF S. M.

    2018-03-01

    The aim of this study was to set the overall production level for each grade of coated peanut product to meet market demands with a minimum production cost. The linear programming model was applied in this study. The proposed model was used to minimize the total production cost based on the limited demand of coated peanuts. The demand values applied to the method was previously forecasted using time series method and production capacity aimed to plan the aggregate production for the next 6 month period. The results indicated that the production planning using the proposed model has resulted a better fitted pattern to the customer demands compared to that of the company policy. The production capacity of product family A, B, and C was relatively stable for the first 3 months of the planning periods, then began to fluctuate over the next 3 months. While, the production capacity of product family D and E was fluctuated over the 6-month planning periods, with the values in the range of 10,864 - 32,580 kg and 255 – 5,069 kg, respectively. The total production cost for all products was 27.06% lower than the production cost calculated using the company’s policy-based method.

  11. Membraneless laminar flow cell for electrocatalytic CO2 reduction with liquid product separation

    International Nuclear Information System (INIS)

    Monroe, Morgan M; Lobaccaro, Peter; Lum, Yanwei; Ager, Joel W

    2017-01-01

    The production of liquid fuel products via electrochemical reduction of CO 2 is a potential path to produce sustainable fuels. However, to be practical, a separation strategy is required to isolate the fuel-containing electrolyte produced at the cathode from the anode and also prevent the oxidation products (i.e. O 2 ) from reaching the cathode. Ion-conducting membranes have been applied in CO 2 reduction reactors to achieve this separation, but they represent an efficiency loss and can be permeable to some product species. An alternative membraneless approach is developed here to maintain product separation through the use of a laminar flow cell. Computational modelling shows that near-unity separation efficiencies are possible at current densities achievable now with metal cathodes via optimization of the spacing between the electrodes and the electrolyte flow rate. Laminar flow reactor prototypes were fabricated with a range of channel widths by 3D printing. CO 2 reduction to formic acid on Sn electrodes was used as the liquid product forming reaction, and the separation efficiency for the dissolved product was evaluated with high performance liquid chromatography. Trends in product separation efficiency with channel width and flow rate were in qualitative agreement with the model, but the separation efficiency was lower, with a maximum value of 90% achieved. (paper)

  12. Incomplete convolutions in production and inventory models

    NARCIS (Netherlands)

    Houtum, van G.J.J.A.N.; Zijm, W.H.M.

    1997-01-01

    In this paper, we study incomplete convolutions of continuous distribution functions, as they appear in the analysis of (multi-stage) production and inventory systems. Three example systems are discussed where these incomplete convolutions naturally arise. We derive explicit, nonrecursive formulae

  13. Modelling fuel cell performance using artificial intelligence

    Science.gov (United States)

    Ogaji, S. O. T.; Singh, R.; Pilidis, P.; Diacakis, M.

    Over the last few years, fuel cell technology has been increasing promisingly its share in the generation of stationary power. Numerous pilot projects are operating worldwide, continuously increasing the amount of operating hours either as stand-alone devices or as part of gas turbine combined cycles. An essential tool for the adequate and dynamic analysis of such systems is a software model that enables the user to assess a large number of alternative options in the least possible time. On the other hand, the sphere of application of artificial neural networks has widened covering such endeavours of life such as medicine, finance and unsurprisingly engineering (diagnostics of faults in machines). Artificial neural networks have been described as diagrammatic representation of a mathematical equation that receives values (inputs) and gives out results (outputs). Artificial neural networks systems have the capacity to recognise and associate patterns and because of their inherent design features, they can be applied to linear and non-linear problem domains. In this paper, the performance of the fuel cell is modelled using artificial neural networks. The inputs to the network are variables that are critical to the performance of the fuel cell while the outputs are the result of changes in any one or all of the fuel cell design variables, on its performance. Critical parameters for the cell include the geometrical configuration as well as the operating conditions. For the neural network, various network design parameters such as the network size, training algorithm, activation functions and their causes on the effectiveness of the performance modelling are discussed. Results from the analysis as well as the limitations of the approach are presented and discussed.

  14. Modelling fuel cell performance using artificial intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Ogaji, S.O.T.; Singh, R.; Pilidis, P.; Diacakis, M. [Power Propulsion and Aerospace Engineering Department, Centre for Diagnostics and Life Cycle Costs, Cranfield University (United Kingdom)

    2006-03-09

    Over the last few years, fuel cell technology has been increasing promisingly its share in the generation of stationary power. Numerous pilot projects are operating worldwide, continuously increasing the amount of operating hours either as stand-alone devices or as part of gas turbine combined cycles. An essential tool for the adequate and dynamic analysis of such systems is a software model that enables the user to assess a large number of alternative options in the least possible time. On the other hand, the sphere of application of artificial neural networks has widened covering such endeavours of life such as medicine, finance and unsurprisingly engineering (diagnostics of faults in machines). Artificial neural networks have been described as diagrammatic representation of a mathematical equation that receives values (inputs) and gives out results (outputs). Artificial neural networks systems have the capacity to recognise and associate patterns and because of their inherent design features, they can be applied to linear and non-linear problem domains. In this paper, the performance of the fuel cell is modelled using artificial neural networks. The inputs to the network are variables that are critical to the performance of the fuel cell while the outputs are the result of changes in any one or all of the fuel cell design variables, on its performance. Critical parameters for the cell include the geometrical configuration as well as the operating conditions. For the neural network, various network design parameters such as the network size, training algorithm, activation functions and their causes on the effectiveness of the performance modelling are discussed. Results from the analysis as well as the limitations of the approach are presented and discussed. (author)

  15. Modeling pure culture heterotrophic production of polyhydroxybutyrate (PHB).

    Science.gov (United States)

    Mozumder, Md Salatul Islam; Goormachtigh, Laurens; Garcia-Gonzalez, Linsey; De Wever, Heleen; Volcke, Eveline I P

    2014-03-01

    In this contribution a mechanistic model describing the production of polyhydroxybutyrate (PHB) through pure-culture fermentation was developed, calibrated and validated for two different substrates, namely glucose and waste glycerol. In both cases, non-growth-associated PHB production was triggered by applying nitrogen limitation. The occurrence of some growth-associated PHB production besides non-growth-associated PHB production was demonstrated, although it is inhibited in the presence of nitrogen. Other phenomena observed experimentally and described by the model included biomass growth on PHB and non-linear product inhibition of PHB production. The accumulated impurities from the waste substrate negatively affected the obtained maximum PHB content. Overall, the developed mathematical model provided an accurate prediction of the dynamic behavior of heterotrophic biomass growth and PHB production in a two-phase pure culture system. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Effects of amalgam corrosion products on human cells

    Energy Technology Data Exchange (ETDEWEB)

    Goldschmidt, P R; Cogen, R B; Taubman, S B [Departments of Periodontics and Pathology, University of Connecticut Health Center, Farmington, Connecticut, U.S.A.

    1976-01-01

    Using three independent criteria, we have found that 10/sup -4/,10/sup -6/M concentrations of ions presumably liberated from the corrosion of dental amalgam produce injurious effects on either human gingival fibroblasts or HeLa cells when the cells are grown in culture. Release of /sup 51/Cr and uptake of trypan blue dye were seen with 10/sup -5/M Hg/sup + +/ and Ag/sup +/. Inhibition of amino acid incorporation into protein-like material was seen with eluates of amalgam and with ionic solutions of most metals comprising dental amalgam. Stannous ion showed little if any cytotoxic potential. These results suggest that corrosion products of amalgam are capable of causing cellular injury or destruction.

  17. Model based process-product design and analysis

    DEFF Research Database (Denmark)

    Gani, Rafiqul

    This paper gives a perspective on modelling and the important role it has within product-process design and analysis. Different modelling issues related to development and application of systematic model-based solution approaches for product-process design is discussed and the need for a hybrid...... model-based framework is highlighted. This framework should be able to manage knowledge-data, models, and associated methods and tools integrated with design work-flows and data-flows for specific product-process design problems. In particular, the framework needs to manage models of different types......, forms and complexity, together with their associated parameters. An example of a model-based system for design of chemicals based formulated products is also given....

  18. A model for marketing planning of new products

    DEFF Research Database (Denmark)

    Martensen, Anne

    1994-01-01

    Executive Summary: 1. A model for forecasting the sales of a new product is presented. This model allows to predict the sales development of a new product before it is actually launched on the market. 2. The model makes separate forecasts for the volume of trial and repeat purchases. It also...... incorporates a special model to explain consumer awareness of the new product. 3. Consumer awareness is explained by distribution (shelf facings and in-store promotion), advertising and giving away free samples. 4. The trial model incorporates the total market potential, the probability of being in a buying...... the product after some time. 6. The model requires three types of data input: market data, market research data, and marketing plan data. Using these data, prediction can be made by a user-friendly PC programme. 7. An example is shown demonstrating that the predictions made by the model were in good...

  19. Economic modelling of pork production-marketing chains

    NARCIS (Netherlands)

    Ouden, den M.

    1996-01-01

    The research described in this thesis was focused on the development of economic simulation and optimization computer models to support decision making with respect to pork production- marketing chains. The models include three production stages: pig farrowing, pig fattening and pig slaughtering

  20. A review of ocean chlorophyll algorithms and primary production models

    Science.gov (United States)

    Li, Jingwen; Zhou, Song; Lv, Nan

    2015-12-01

    This paper mainly introduces the five ocean chlorophyll concentration inversion algorithm and 3 main models for computing ocean primary production based on ocean chlorophyll concentration. Through the comparison of five ocean chlorophyll inversion algorithm, sums up the advantages and disadvantages of these algorithm,and briefly analyzes the trend of ocean primary production model.

  1. Radiobiological analyse based on cell cluster models

    International Nuclear Information System (INIS)

    Lin Hui; Jing Jia; Meng Damin; Xu Yuanying; Xu Liangfeng

    2010-01-01

    The influence of cell cluster dimension on EUD and TCP for targeted radionuclide therapy was studied using the radiobiological method. The radiobiological features of tumor with activity-lack in core were evaluated and analyzed by associating EUD, TCP and SF.The results show that EUD will increase with the increase of tumor dimension under the activity homogeneous distribution. If the extra-cellular activity was taken into consideration, the EUD will increase 47%. Under the activity-lack in tumor center and the requirement of TCP=0.90, the α cross-fire influence of 211 At could make up the maximum(48 μm)3 activity-lack for Nucleus source, but(72 μm)3 for Cytoplasm, Cell Surface, Cell and Voxel sources. In clinic,the physician could prefer the suggested dose of Cell Surface source in case of the future of local tumor control for under-dose. Generally TCP could well exhibit the effect difference between under-dose and due-dose, but not between due-dose and over-dose, which makes TCP more suitable for the therapy plan choice. EUD could well exhibit the difference between different models and activity distributions,which makes it more suitable for the research work. When the user uses EUD to study the influence of activity inhomogeneous distribution, one should keep the consistency of the configuration and volume of the former and the latter models. (authors)

  2. Interaction of Defensins with Model Cell Membranes

    Science.gov (United States)

    Sanders, Lori K.; Schmidt, Nathan W.; Yang, Lihua; Mishra, Abhijit; Gordon, Vernita D.; Selsted, Michael E.; Wong, Gerard C. L.

    2009-03-01

    Antimicrobial peptides (AMPs) comprise a key component of innate immunity for a wide range of multicellular organisms. For many AMPs, activity comes from their ability to selectively disrupt and lyse bacterial cell membranes. There are a number of proposed models for this action, but the detailed molecular mechanism of selective membrane permeation remains unclear. Theta defensins are circularized peptides with a high degree of selectivity. We investigate the interaction of model bacterial and eukaryotic cell membranes with theta defensins RTD-1, BTD-7, and compare them to protegrin PG-1, a prototypical AMP, using synchrotron small angle x-ray scattering (SAXS). The relationship between membrane composition and peptide induced changes in membrane curvature and topology is examined. By comparing the membrane phase behavior induced by these different peptides we will discuss the importance of amino acid composition and placement on membrane rearrangement.

  3. A continuous-time control model on production planning network ...

    African Journals Online (AJOL)

    A continuous-time control model on production planning network. DEA Omorogbe, MIU Okunsebor. Abstract. In this paper, we give a slightly detailed review of Graves and Hollywood model on constant inventory tactical planning model for a job shop. The limitations of this model are pointed out and a continuous time ...

  4. Developing a Decision Model of Sustainable Product Design and Development from Product Servicizing in Taiwan

    Science.gov (United States)

    Huang, Yu-Chen; Tu, Jui-Che; Hung, So-Jeng

    2016-01-01

    In response to the global trend of low carbon and the concept of sustainable development, enterprises need to develop R&D for the manufacturing of energy-saving and sustainable products and low carbon products. Therefore, the purpose of this study was to construct a decision model for sustainable product design and development from product…

  5. Studying reaction products in a lithium thionyl chloride cell

    International Nuclear Information System (INIS)

    Vol'fkovich, Yu.M.; Sosenkin, V.E.; Nikol'skaya, N.F.; Blinov, I.A.

    1999-01-01

    Change in the mass, volume and chemical composition of reaction insoluble products (RIP) formed in the course of discharge of thionyl chloride lithium cells under different conditions has been studied by the methods of gravimetry, volumetry and element analysis. It has been ascertained that the measured volume and mass of RIP essentially (by a factor of 1.1-1.8) exceed the calculated values, proceeding from the reaction stoichiometry. Besides lithium chloride and sulfur during discharge additional RIP is formed as LiAlCl 4 · SOCl 2 solvate, its share increasing with temperature decrease, increase in current density and electrolyte concentration [ru

  6. A system dynamics model to determine products mix

    Directory of Open Access Journals (Sweden)

    Mahtab Hajghasem

    2014-02-01

    Full Text Available This paper presents an implementation of system dynamics model to determine appropriate product mix by considering various factors such as labor, materials, overhead, etc. for an Iranian producer of cosmetic and sanitary products. The proposed model of this paper considers three hypotheses including the relationship between product mix and profitability, optimum production capacity and having minimum amount of storage to take advantage of low cost production. The implementation of system dynamics on VENSIM software package has confirmed all three hypotheses of the survey and suggested that in order to reach better mix product, it is necessary to reach optimum production planning, take advantage of all available production capacities and use inventory management techniques.

  7. A production model and maintenance planning model for the process industry

    NARCIS (Netherlands)

    Ashayeri, J.; Teelen, A.; Selen, W.J.

    1995-01-01

    In this paper a model is developed to simultaneously plan preventive maintenance and production in a process industry environment, where maintenance planning is extremely important. The model schedules production jobs and preventive maintenance jobs, while minimizing costs associated with

  8. Exotic hadron production in a quark combination model

    International Nuclear Information System (INIS)

    Han Wei; Shao Fenglan; Li Shiyuan; Shang Yonghui; Yao Tao

    2009-01-01

    The philosophy on production of exotic hadrons (multiquark states) in the framework of the quark combination model is investigated, taking f 0 (980) as an example. The production rate and p T spectra of f 0 (980) considered as (ss) or (sqsq), respectively, are calculated and compared in Au+Au collisions at √(s NN )=200 GeV. The unitarity of various combination models, when open for exotic hadron production, is addressed.

  9. Simulated conditions of microgravity suppress progesterone production by luteal cells of the pregnant rat

    Science.gov (United States)

    Bhat, G. K.; Yang, H.; Sridaran, R.

    2001-01-01

    The purpose of this study was to assess whether simulated conditions of microgravity induce changes in the production of progesterone by luteal cells of the pregnant rat ovary using an in vitro model system. The microgravity environment was simulated using either a high aspect ratio vessel (HARV) bioreactor with free fall or a clinostat without free fall of cells. A mixed population of luteal cells isolated from the corpora lutea of day 8 pregnant rats was attached to cytodex microcarrier beads (cytodex 3). These anchorage dependent cells were placed in equal numbers in the HARV or a spinner flask control vessel in culture conditions. It was found that HARV significantly reduced the daily production of progesterone from day 1 through day 8 compared to controls. Scanning electron microscopy showed that cells attached to the microcarrier beads throughout the duration of the experiment in both types of culture vessels. Cells cultured in chamber slide flasks and placed in a clinostat yielded similar results when compared to those in the HARV. Also, when they were stained by Oil Red-O for lipid droplets, the clinostat flasks showed a larger number of stained cells compared to control flasks at 48 h. Further, the relative amount of Oil Red-O staining per milligram of protein was found to be higher in the clinostat than in the control cells at 48 h. It is speculated that the increase in the level of lipid content in cells subjected to simulated conditions of microgravity may be due to a disruption in cholesterol transport and/or lesions in the steroidogenic pathway leading to a fall in the synthesis of progesterone. Additionally, the fall in progesterone in simulated conditions of microgravity could be due to apoptosis of luteal cells.

  10. Modeling of SONOS Memory Cell Erase Cycle

    Science.gov (United States)

    Phillips, Thomas A.; MacLeod, Todd C.; Ho, Fat H.

    2011-01-01

    Utilization of Silicon-Oxide-Nitride-Oxide-Silicon (SONOS) nonvolatile semiconductor memories as a flash memory has many advantages. These electrically erasable programmable read-only memories (EEPROMs) utilize low programming voltages, have a high erase/write cycle lifetime, are radiation hardened, and are compatible with high-density scaled CMOS for low power, portable electronics. In this paper, the SONOS memory cell erase cycle was investigated using a nonquasi-static (NQS) MOSFET model. Comparisons were made between the model predictions and experimental data.

  11. Evolving cell models for systems and synthetic biology.

    Science.gov (United States)

    Cao, Hongqing; Romero-Campero, Francisco J; Heeb, Stephan; Cámara, Miguel; Krasnogor, Natalio

    2010-03-01

    This paper proposes a new methodology for the automated design of cell models for systems and synthetic biology. Our modelling framework is based on P systems, a discrete, stochastic and modular formal modelling language. The automated design of biological models comprising the optimization of the model structure and its stochastic kinetic constants is performed using an evolutionary algorithm. The evolutionary algorithm evolves model structures by combining different modules taken from a predefined module library and then it fine-tunes the associated stochastic kinetic constants. We investigate four alternative objective functions for the fitness calculation within the evolutionary algorithm: (1) equally weighted sum method, (2) normalization method, (3) randomly weighted sum method, and (4) equally weighted product method. The effectiveness of the methodology is tested on four case studies of increasing complexity including negative and positive autoregulation as well as two gene networks implementing a pulse generator and a bandwidth detector. We provide a systematic analysis of the evolutionary algorithm's results as well as of the resulting evolved cell models.

  12. Modeling population dynamics of mitochondria in mammalian cells

    Science.gov (United States)

    Kornick, Kellianne; Das, Moumita

    Mitochondria are organelles located inside eukaryotic cells and are essential for several key cellular processes such as energy (ATP) production, cell signaling, differentiation, and apoptosis. All organisms are believed to have low levels of variation in mitochondrial DNA (mtDNA), and alterations in mtDNA are connected to a range of human health conditions, including epilepsy, heart failure, Parkinsons disease, diabetes, and multiple sclerosis. Therefore, understanding how changes in mtDNA accumulate over time and are correlated to changes in mitochondrial function and cell properties can have a profound impact on our understanding of cell physiology and the origins of some diseases. Motivated by this, we develop and study a mathematical model to determine which cellular parameters have the largest impact on mtDNA population dynamics. The model consists of coupled ODEs to describe subpopulations of healthy and dysfunctional mitochondria subject to mitochondrial fission, fusion, autophagy, and mutation. We study the time evolution and stability of each sub-population under specific selection biases and pressures by tuning specific terms in our model. Our results may provide insights into how sub-populations of mitochondria survive and evolve under different selection pressures. This work was supported by a Grant from the Moore Foundation.

  13. ANALYSIS OF ECONOMIC MODELS OF POTATO PRODUCTION IN MONTENEGRO

    Directory of Open Access Journals (Sweden)

    Miomir JOVANOVIC

    2014-04-01

    Full Text Available The northern region of Montenegro represents a very important resource for agricultural production. However, the depopulation of the analysed area, pronounced in-kind character of production without significant participation of market producers, lack of market research, stronger vertical and horizontal connection between primary production and processing sectors have significant impacts causing the low level of competitiveness of agricultural production. Potato production in the analysed area has recorded positive trends in last ten years. This paper presents economic models of agriculture households on the analysed area from the potatoes production point of view.

  14. Hydrogen production by steam reforming methanol for polymer electrolyte fuel cells

    International Nuclear Information System (INIS)

    Amphlett, J.C.; Creber, K.A.M.; Davis, J.M.; Mann, R.F.; Peppley, B.A.; Stokes, D.M.

    1993-01-01

    Catalytic steam reforming of methanol has been studied as a means of generating hydrogen for a polymer electrolyte membrane fuel cell. A semi-empirical model of the kinetics of the catalytic steam reforming of methanol over Cu O/Zn O/Al 2 O 3 catalyst has been developed. This model is able to predict the performance of the reformer with respect to the various parameters important in developing an integrated reformer-polymer fuel cell system. A set of sample calculations of reformer temperature and CO production are given. The impact of the performance of the reformer catalyst on the design of the overall fuel cell power system is discussed. The selectivity of the catalyst to minimize CO content in the fuel gas is shown to be more critical than was previously believed. 4 figs., 4 tabs., 11 refs

  15. Experimental Model to Study the Role of Retinoblastoma Gene Product (pRb) for Determination of Adipocyte Differentiation.

    Science.gov (United States)

    Popov, B V; Shilo, P S; Zhidkova, O V; Zaichik, A M; Petrov, N S

    2015-06-01

    Using stable constitutive expression of retinoblastoma gene product (pRb) in polypotent mesenchymal 10T1/2 cells we obtained stable cell lines hyperexpressing functionally active or inactive mutant pRb. The cells producing active exogenous pRb demonstrated high sensitivity to adipocyte differentiation inductors, whereas production of inactive form of the exogenous protein suppressed adipocyte differentiation. The obtained lines can serve as the experimental model for studying the role of pRb in determination of adipocyte differentiation.

  16. 78 FR 49528 - Consolidation of Wound Care Products Containing Live Cells

    Science.gov (United States)

    2013-08-14

    ...] Consolidation of Wound Care Products Containing Live Cells AGENCY: Food and Drug Administration, HHS. ACTION... certain wound care products containing live cells from the Center for Devices and Radiological Health... CDRH and CBER. FDA believes that as more wound care products containing live cells are developed such...

  17. Whole-cell Escherichia coli lactate biosensor for monitoring mammalian cell cultures during biopharmaceutical production.

    Science.gov (United States)

    Goers, Lisa; Ainsworth, Catherine; Goey, Cher Hui; Kontoravdi, Cleo; Freemont, Paul S; Polizzi, Karen M

    2017-06-01

    Many high-value added recombinant proteins, such as therapeutic glycoproteins, are produced using mammalian cell cultures. In order to optimize the productivity of these cultures it is important to monitor cellular metabolism, for example the utilization of nutrients and the accumulation of metabolic waste products. One metabolic waste product of interest is lactic acid (lactate), overaccumulation of which can decrease cellular growth and protein production. Current methods for the detection of lactate are limited in terms of cost, sensitivity, and robustness. Therefore, we developed a whole-cell Escherichia coli lactate biosensor based on the lldPRD operon and successfully used it to monitor lactate concentration in mammalian cell cultures. Using real samples and analytical validation we demonstrate that our biosensor can be used for absolute quantification of metabolites in complex samples with high accuracy, sensitivity, and robustness. Importantly, our whole-cell biosensor was able to detect lactate at concentrations more than two orders of magnitude lower than the industry standard method, making it useful for monitoring lactate concentrations in early phase culture. Given the importance of lactate in a variety of both industrial and clinical contexts we anticipate that our whole-cell biosensor can be used to address a range of interesting biological questions. It also serves as a blueprint for how to capitalize on the wealth of genetic operons for metabolite sensing available in nature for the development of other whole-cell biosensors. Biotechnol. Bioeng. 2017;114: 1290-1300. © 2017 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc. © 2017 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc.

  18. Whole‐cell Escherichia coli lactate biosensor for monitoring mammalian cell cultures during biopharmaceutical production

    Science.gov (United States)

    Goers, Lisa; Ainsworth, Catherine; Goey, Cher Hui; Kontoravdi, Cleo; Freemont, Paul S.

    2017-01-01

    ABSTRACT Many high‐value added recombinant proteins, such as therapeutic glycoproteins, are produced using mammalian cell cultures. In order to optimize the productivity of these cultures it is important to monitor cellular metabolism, for example the utilization of nutrients and the accumulation of metabolic waste products. One metabolic waste product of interest is lactic acid (lactate), overaccumulation of which can decrease cellular growth and protein production. Current methods for the detection of lactate are limited in terms of cost, sensitivity, and robustness. Therefore, we developed a whole‐cell Escherichia coli lactate biosensor based on the lldPRD operon and successfully used it to monitor lactate concentration in mammalian cell cultures. Using real samples and analytical validation we demonstrate that our biosensor can be used for absolute quantification of metabolites in complex samples with high accuracy, sensitivity, and robustness. Importantly, our whole‐cell biosensor was able to detect lactate at concentrations more than two orders of magnitude lower than the industry standard method, making it useful for monitoring lactate concentrations in early phase culture. Given the importance of lactate in a variety of both industrial and clinical contexts we anticipate that our whole‐cell biosensor can be used to address a range of interesting biological questions. It also serves as a blueprint for how to capitalize on the wealth of genetic operons for metabolite sensing available in nature for the development of other whole‐cell biosensors. Biotechnol. Bioeng. 2017;114: 1290–1300. © 2017 The Authors. Biotechnology and Bioengineering Published by Wiley Periodicals, Inc. PMID:28112405

  19. Modelling energy consumption in a manufacturing plant using productivity KPIs

    Energy Technology Data Exchange (ETDEWEB)

    Gallachoir, Brian O.; Cahill, Caiman (Sustainable Energy Research Group, Dept. of Civil and Environmental Engineering, Univ. College Cork (Ireland))

    2009-07-01

    Energy efficiency initiatives in industrial plants are often focused on getting energy-consuming utilities and devices to operate more efficiently, or on conserving energy. While such device-oriented energy efficiency measures can achieve considerable savings, greater energy efficiency improvement may be achieved by improving the overall productivity and quality of manufacturing processes. The paper highlights the observed relationship between productivity and energy efficiency using aggregated data on unit consumption and production index data for Irish industry. Past studies have developed simple top-down models of final energy consumption in manufacturing plants using energy consumption and production output figures, but these models do not help identify opportunities for energy savings that could achieved through increased productivity. This paper proposes an improved and innovative method of modelling plant final energy demand that introduces standard productivity Key Performance Indicators (KPIs) into the model. The model demonstrates the relationship between energy consumption and productivity, and uses standard productivity metrics to identify the areas of manufacturing activity that offer the most potential for improved energy efficiency. The model provides a means of comparing the effect of device-oriented energy efficiency measures with the potential for improved energy efficiency through increased productivity.

  20. Enteral peptide formulas inhibit radiation induced enteritis and apoptosis in intestinal epithelial cells and suppress the expression and function of Alzheimer's and cell division control gene products

    International Nuclear Information System (INIS)

    Cope, F.O.; Issinger, O.G.; McArdle, A.H.; Shapiro, J.; Tomei, L.D.

    1991-01-01

    Studies have shown that patients receiving enteral peptide formulas prior to irradiation have a significantly reduced incidence of enteritis and express a profound increase in intestinal cellularity. Two conceptual approaches were taken to describe this response. First was the evaluation in changes in programmed intestinal cell death and secondly the evaluation of a gene product controlling cell division cycling. This study provided a relationship between the ratio of cell death to cell formulations. The results indicate that in the canine and murine models, irradiation induces expression of the Alzheimer's gene in intestinal crypt cells, while the incidence of apoptosis in apical cells is significantly increased. The use of peptide enteral formulations suppresses the expression of the Alzheimer's gene in crypt cells, while apoptosis is eliminated in the apical cells of the intestine. Concomitantly, enteral peptide formulations suppress the function of the CK-II gene product in the basal and baso-lateral cells of the intestine. These data indicate that although the mitotic index is significantly reduced in enterocytes, this phenomenon alone is not sufficient to account for the peptide-induced radio-resistance of the intestine. The data also indicate a significant reduction of normal apoptosis in the upper lateral and apical cells of the intestinal villi. Thus, the ratio of cell death to cell replacement is significantly decreased resulting in an increase in villus height and hypertrophy of the apical villus cells. Thus, peptide solutions should be considered as an adjunct treatment both in radio- and chemotherapy

  1. Sustainability Assessment Model in Product Development

    Science.gov (United States)

    Turan, Faiz Mohd; Johan, Kartina; Nor, Nik Hisyamudin Muhd; Omar, Badrul

    2017-08-01

    Faster and more efficient development of innovative and sustainable products has become the focus for manufacturing companies in order to remain competitive in today’s technologically driven world. Design concept evaluation which is the end of conceptual design is one of the most critical decision points. It relates to the final success of product development, because poor criteria assessment in design concept evaluation can rarely compensated at the later stages. Furthermore, consumers, investors, shareholders and even competitors are basing their decisions on what to buy or invest in, from whom, and also on what company report, and sustainability is one of a critical component. In this research, a new methodology of sustainability assessment in product development for Malaysian industry has been developed using integration of green project management, new scale of “Weighting criteria” and Rough-Grey Analysis. This method will help design engineers to improve the effectiveness and objectivity of the sustainable design concept evaluation, enable them to make better-informed decisions before finalising their choice and consequently create value to the company or industry. The new framework is expected to provide an alternative to existing methods.

  2. CHO On A Detox: Removing By-Product Formation Through Cell Engineering

    DEFF Research Database (Denmark)

    Pereira, Sara; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    Chinese Hamster Ovary (CHO) cells are the preferred hosts for the production of therapeutic glycoproteins. However, there is a need for improvement of the bioprocesses towards increased cell growth and higher productivities without compromising the product quality. Efforts to obtain tailor-made p......-made products with the desired properties that meet the requirements of regulatory authorities are continuously being made. Of equal relevance is to develop methods to engineer cell lines with improved by-product metabolism....

  3. Mining Product Data Models: A Case Study

    Directory of Open Access Journals (Sweden)

    Cristina-Claudia DOLEAN

    2014-01-01

    Full Text Available This paper presents two case studies used to prove the validity of some data-flow mining algorithms. We proposed the data-flow mining algorithms because most part of mining algorithms focuses on the control-flow perspective. First case study uses event logs generated by an ERP system (Navision after we set several trackers on the data elements needed in the process analyzed; while the second case study uses the event logs generated by YAWL system. We offered a general solution of data-flow model extraction from different data sources. In order to apply the data-flow mining algorithms the event logs must comply a certain format (using InputOutput extension. But to respect this format, a set of conversion tools is needed. We depicted the conversion tools used and how we got the data-flow models. Moreover, the data-flow model is compared to the control-flow model.

  4. Integrated cell and process engineering for improved transient production of a "difficult-to-express" fusion protein by CHO cells.

    Science.gov (United States)

    Johari, Yusuf B; Estes, Scott D; Alves, Christina S; Sinacore, Marty S; James, David C

    2015-12-01

    Based on an optimized electroporation protocol, we designed a rapid, milliliter-scale diagnostic transient production assay to identify limitations in the ability of Chinese hamster ovary (CHO) cells to produce a model "difficult-to-express" homodimeric Fc-fusion protein, Sp35Fc, that exhibited very low volumetric titer and intracellular formation of disulfide-bonded oligomeric aggregates post-transfection. As expression of Sp35Fc induced an unfolded protein response in transfected host cells, we utilized the transient assay to compare, in parallel, multiple functionally diverse strategies to engineer intracellular processing of Sp35Fc in order to increase production and reduce aggregation as two discrete design objectives. Specifically, we compared the effect of (i) co-expression of ER-resident molecular chaperones (BiP, PDI, CypB) or active forms of UPR transactivators (ATF6c, XBP1s) at varying recombinant gene load, (ii) addition of small molecules known to act as chemical chaperones (PBA, DMSO, glycerol, betaine, TMAO) or modulate UPR signaling (PERK inhibitor GSK2606414) at varying concentration, (iii) a reduction in culture temperature to 32°C. Using this information, we designed a biphasic, Sp35Fc-specific transient manufacturing process mediated by lipofection that utilized CypB co-expression at an optimal Sp35Fc:CypB gene ratio of 5:1 to initially maximize transfected cell proliferation, followed by addition of a combination of PBA (0.5 mM) and glycerol (1% v/v) at the onset of stationary phase to maximize cell specific production and eliminate Sp35Fc aggregation. Using this optimal, engineered process transient Sp35Fc production was significantly increased sixfold over a 12 day production process with no evidence of disulfide-bonded aggregates. Finally, transient production in clonally derived sub-populations (derived from parental CHO host) screened for a heritably improved capability to produce Sp35Fc was also significantly improved by the optimized

  5. Lattice Model for Production of Gas

    KAUST Repository

    Marder, M.

    2017-12-01

    We define a lattice model for rock, absorbers, and gas that makes it possible to examine the flow of gas to a complicated absorbing boundary over long periods of time. The motivation is to deduce the geometry of the boundary from the time history of gas absorption. We find a solution to this model using Green\\'s function techniques, and apply the solution to three absorbing networks of increasing complexity.

  6. Lattice Model for Production of Gas

    OpenAIRE

    Marder, M.; Eftekhari, Behzad; Patzek, Tadeusz W

    2017-01-01

    We define a lattice model for rock, absorbers, and gas that makes it possible to examine the flow of gas to a complicated absorbing boundary over long periods of time. The motivation is to deduce the geometry of the boundary from the time history of gas absorption. We find a solution to this model using Green's function techniques, and apply the solution to three absorbing networks of increasing complexity.

  7. EFFECTIVE FACTORS AND MODEL SYSTEMS IN THE INDUSTRIAL PRODUCTION OF NISIN

    Directory of Open Access Journals (Sweden)

    Ömer ŞİMŞEK

    2007-01-01

    Full Text Available Nisin is the first bacteriocin identified in Lactococcus lactis and belongs to type 1 lanthibiotic group. High nisin production in cultured media is related with the composition of fermentation medium, pH, produced nisin concentration and most importantly growth amount of cell. For industrial purpose, batch, fed-batch and continue fermentation systems were developed by regarding these factors. Maintaining efficient production of nisin having important potential at preservation of foods is important for both industrial production and using as starter culture. In this review the fermentation factors at nisin production were outlined and constructed model systems were compared.

  8. Enriching step-based product information models to support product life-cycle activities

    Science.gov (United States)

    Sarigecili, Mehmet Ilteris

    The representation and management of product information in its life-cycle requires standardized data exchange protocols. Standard for Exchange of Product Model Data (STEP) is such a standard that has been used widely by the industries. Even though STEP-based product models are well defined and syntactically correct, populating product data according to these models is not easy because they are too big and disorganized. Data exchange specifications (DEXs) and templates provide re-organized information models required in data exchange of specific activities for various businesses. DEXs show us it would be possible to organize STEP-based product models in order to support different engineering activities at various stages of product life-cycle. In this study, STEP-based models are enriched and organized to support two engineering activities: materials information declaration and tolerance analysis. Due to new environmental regulations, the substance and materials information in products have to be screened closely by manufacturing industries. This requires a fast, unambiguous and complete product information exchange between the members of a supply chain. Tolerance analysis activity, on the other hand, is used to verify the functional requirements of an assembly considering the worst case (i.e., maximum and minimum) conditions for the part/assembly dimensions. Another issue with STEP-based product models is that the semantics of product data are represented implicitly. Hence, it is difficult to interpret the semantics of data for different product life-cycle phases for various application domains. OntoSTEP, developed at NIST, provides semantically enriched product models in OWL. In this thesis, we would like to present how to interpret the GD & T specifications in STEP for tolerance analysis by utilizing OntoSTEP.

  9. Novel piplartine-containing ruthenium complexes: synthesis, cell growth inhibition, apoptosis induction and ROS production on HCT116 cells.

    Science.gov (United States)

    D'Sousa Costa, Cinara O; Araujo Neto, João H; Baliza, Ingrid R S; Dias, Rosane B; Valverde, Ludmila de F; Vidal, Manuela T A; Sales, Caroline B S; Rocha, Clarissa A G; Moreira, Diogo R M; Soares, Milena B P; Batista, Alzir A; Bezerra, Daniel P

    2017-11-28

    Piplartine (piperlongumine) is a plant-derived molecule that has been receiving intense interest due to its anticancer characteristics that target the oxidative stress. In the present paper, two novel piplartine-containing ruthenium complexes [Ru(piplartine)(dppf)(bipy)](PF 6 ) 2 (1) and [Ru(piplartine)(dppb)(bipy)](PF 6 ) 2 (2) were synthesized and investigated for their cellular and molecular responses on cancer cell lines. We found that both complexes are more potent than metal-free piplartine in a panel of cancer cell lines on monolayer cultures, as well in 3D model of cancer multicellular spheroids formed from human colon carcinoma HCT116 cells. Mechanistic studies uncovered that the complexes reduced the cell growth and caused phosphatidylserine externalization, internucleosomal DNA fragmentation, caspase-3 activation and loss of the mitochondrial transmembrane potential on HCT116 cells. Moreover, the pre-treatment with Z-VAD(OMe)-FMK, a pan-caspase inhibitor, reduced the complexes-induced apoptosis, indicating cell death by apoptosis through caspase-dependent and mitochondrial intrinsic pathways. Treatment with the complexes also caused a marked increase in the production of reactive oxygen species (ROS), including hydrogen peroxide, superoxide anion and nitric oxide, and decreased reduced glutathione levels. Application of N-acetyl-cysteine, an antioxidant, reduced the ROS levels and apoptosis induced by the complexes, indicating activation of ROS-mediated apoptosis pathway. RNA transcripts of several genes, including gene related to the cell cycle, apoptosis and oxidative stress, were regulated under treatment. However, the complexes failed to induce DNA intercalation. In conclusion, the complexes are more potent than piplartine against different cancer cell lines and are able to induce caspase-dependent and mitochondrial intrinsic apoptosis on HCT116 cells by ROS-mediated pathway.

  10. Microbial Reverse Electrodialysis Cells for Synergistically Enhanced Power Production

    KAUST Repository

    Kim, Younggy

    2011-07-01

    A new type of bioelectrochemical system for producing electrical power, called a microbial reverse-electrodialysis cell (MRC), was developed to increase voltages and power densities compared to those generated individually by microbial fuel cells (MFCs) or reverse electrodialysis (RED) systems. In RED systems, electrode overpotentials create significant energy losses due to thermodynamically unfavorable electrode reactions, and therefore a large number of stacked cells must be used to have significant energy recovery. This results in high capital costs for the large number of membranes, and increases energy losses from pumping water through a large number of cells. In an MRC, high overpotentials are avoided through oxidation of organic matter by exoelectrogenic bacteria on the anode and oxygen reduction on the cathode. An MRC containing only five pairs of RED cells, fed solutions typical of seawater (600 mM NaCl) and river water (12 mM NaCl) at 0.85 mL/min, produced up to 3.6 W/m2 (cathode surface area) and 1.2-1.3 V with acetate as a substrate. Pumping accounted for <2% of the produced power. A higher flow rate (1.55 mL/min) increased power densities up to 4.3 W/m2. COD removal was 98% with a Coulombic efficiency of 64%. Power production by the individual components was substantially lower with 0.7 W/m2 without salinity driven energy, and <0.015 W/m2 with reduced exoelectrogenic activity due to substrate depletion. These results show that the combination of an MFC and a RED stack synergistically increases performance relative to the individual systems, producing a new type of system that can be used to more efficiently capture salinity driven energy from seawater and river water. © 2011 American Chemical Society.

  11. Influence of adhesion and bacteriocin production by Lactobacillus salivarius on the intestinal epithelial cell transcriptional response.

    Science.gov (United States)

    O'Callaghan, John; Buttó, Ludovica F; MacSharry, John; Nally, Kenneth; O'Toole, Paul W

    2012-08-01

    Lactobacillus salivarius strain UCC118 is a human intestinal isolate that has been extensively studied for its potential probiotic effects in human and animal models. The objective of this study was to determine the effect of L. salivarius UCC118 on gene expression responses in the Caco-2 cell line to improve understanding of how the strain might modulate intestinal epithelial cell phenotypes. Exposure of Caco-2 cells to UCC118 led to the induction of several human genes (TNFAIP3, NFKBIA, and BIRC3) that are negative regulators of inflammatory signaling pathways. Induction of chemokines (CCL20, CXCL-1, and CXCL-2) with antimicrobial functions was also observed. Disruption of the UCC118 sortase gene srtA causes reduced bacterial adhesion to epithelial cells. Transcription of three mucin genes was reduced significantly when Caco-2 cells were stimulated with the ΔsrtA derivative of UCC118 compared to cells stimulated with the wild type, but there was no significant change in the transcription levels of the anti-inflammatory genes. UCC118 genes that were significantly upregulated upon exposure to Caco-2 cells were identified by bacterial genome microarray and consisted primarily of two groups of genes connected with purine metabolism and the operon for synthesis of the Abp118 bacteriocin. Following incubation with Caco-2 cells, the bacteriocin synthesis genes were transcribed at higher levels in the wild type than in the ΔsrtA derivative. These data indicate that L. salivarius UCC118 influences epithelial cells both through modulation of the inflammatory response and by modulation of intestinal cell mucin production. Sortase-anchored cell surface proteins of L. salivarius UCC118 have a central role in promoting the interaction between the bacterium and epithelial cells.

  12. In Vitro Large Scale Production of Human Mature Red Blood Cells from Hematopoietic Stem Cells by Coculturing with Human Fetal Liver Stromal Cells

    Directory of Open Access Journals (Sweden)

    Jiafei Xi

    2013-01-01

    Full Text Available In vitro models of human erythropoiesis are useful in studying the mechanisms of erythroid differentiation in normal and pathological conditions. Here we describe an erythroid liquid culture system starting from cord blood derived hematopoietic stem cells (HSCs. HSCs were cultured for more than 50 days in erythroid differentiation conditions and resulted in a more than 109-fold expansion within 50 days under optimal conditions. Homogeneous erythroid cells were characterized by cell morphology, flow cytometry, and hematopoietic colony assays. Furthermore, terminal erythroid maturation was improved by cosculturing with human fetal liver stromal cells. Cocultured erythroid cells underwent multiple maturation events, including decrease in size, increase in glycophorin A expression, and nuclear condensation. This process resulted in extrusion of the pycnotic nuclei in up to 80% of the cells. Importantly, they possessed the capacity to express the adult definitive β-globin chain upon further maturation. We also show that the oxygen equilibrium curves of the cord blood-differentiated red blood cells (RBCs are comparable to normal RBCs. The large number and purity of erythroid cells and RBCs produced from cord blood make this method useful for fundamental research in erythroid development, and they also provide a basis for future production of available RBCs for transfusion.

  13. A model for improving microbial biofuel production using a synthetic feedback loop

    Energy Technology Data Exchange (ETDEWEB)

    Dunlop, Mary; Keasling, Jay; Mukhopadhyay, Aindrila

    2011-07-14

    Cells use feedback to implement a diverse range of regulatory functions. Building synthetic feedback control systems may yield insight into the roles that feedback can play in regulation since it can be introduced independently of native regulation, and alternative control architectures can be compared. We propose a model for microbial biofuel production where a synthetic control system is used to increase cell viability and biofuel yields. Although microbes can be engineered to produce biofuels, the fuels are often toxic to cell growth, creating a negative feedback loop that limits biofuel production. These toxic effects may be mitigated by expressing efflux pumps that export biofuel from the cell. We developed a model for cell growth and biofuel production and used it to compare several genetic control strategies for their ability to improve biofuel yields. We show that controlling efflux pump expression directly with a biofuel-responsive promoter is a straight forward way of improving biofuel production. In addition, a feed forward loop controller is shown to be versatile at dealing with uncertainty in biofuel production rates.

  14. Mitochondrial biogenesis and energy production in differentiating murine stem cells: a functional metabolic study.

    Science.gov (United States)

    Han, Sungwon; Auger, Christopher; Thomas, Sean C; Beites, Crestina L; Appanna, Vasu D

    2014-02-01

    The significance of metabolic networks in guiding the fate of the stem cell differentiation is only beginning to emerge. Oxidative metabolism has been suggested to play a major role during this process. Therefore, it is critical to understand the underlying mechanisms of metabolic alterations occurring in stem cells to manipulate the ultimate outcome of these pluripotent cells. Here, using P19 murine embryonal carcinoma cells as a model system, the role of mitochondrial biogenesis and the modulation of metabolic networks during dimethyl sulfoxide (DMSO)-induced differentiation are revealed. Blue native polyacrylamide gel electrophoresis (BN-PAGE) technology aided in profiling key enzymes, such as hexokinase (HK) [EC 2.7.1.1], glucose-6-phosphate isomerase (GPI) [EC 5.3.1.9], pyruvate kinase (PK) [EC 2.7.1.40], Complex I [EC 1.6.5.3], and Complex IV [EC 1.9.3.1], that are involved in the energy budget of the differentiated cells. Mitochondrial adenosine triphosphate (ATP) production was shown to be increased in DMSO-treated cells upon exposure to the tricarboxylic acid (TCA) cycle substrates, such as succinate and malate. The increased mitochondrial activity and biogenesis were further confirmed by immunofluorescence microscopy. Collectively, the results indicate that oxidative energy metabolism and mitochondrial biogenesis were sharply upregulated in DMSO-differentiated P19 cells. This functional metabolic and proteomic study provides further evidence that modulation of mitochondrial energy metabolism is a pivotal component of the cellular differentiation process and may dictate the final destiny of stem cells.

  15. Fuzzy production planning models for an unreliable production system with fuzzy production rate and stochastic/fuzzy demand rate

    Directory of Open Access Journals (Sweden)

    K. A. Halim

    2011-01-01

    Full Text Available In this article, we consider a single-unit unreliable production system which produces a single item. During a production run, the production process may shift from the in-control state to the out-of-control state at any random time when it produces some defective items. The defective item production rate is assumed to be imprecise and is characterized by a trapezoidal fuzzy number. The production rate is proportional to the demand rate where the proportionality constant is taken to be a fuzzy number. Two production planning models are developed on the basis of fuzzy and stochastic demand patterns. The expected cost per unit time in the fuzzy sense is derived in each model and defuzzified by using the graded mean integration representation method. Numerical examples are provided to illustrate the optimal results of the proposed fuzzy models.

  16. Two agricultural production data libraries for risk assessment models

    International Nuclear Information System (INIS)

    Baes, C.F. III; Shor, R.W.; Sharp, R.D.; Sjoreen, A.L.

    1985-01-01

    Two data libraries based on the 1974 US Census of Agriculture are described. The data packages (AGDATC and AGDATG) are available from the Radiation Shielding Information Center (RSIC), Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831. Agricultural production and land-use information by county (AGDATC) or by 1/2 by 1/2 degree longitude-latitude grid cell (AGDATG) provide geographical resolution of the data. The libraries were designed for use in risk assessment models that simulate the transport of radionuclides from sources of airborne release through food chains to man. However, they are also suitable for use in the assessment of other airborne pollutants that can affect man from a food ingestion pathway such as effluents from synfuels or coal-fired power plants. The principal significance of the data libraries is that they provide default location-specific food-chain transport parameters when site-specific information are unavailable. Plant food categories in the data libraries include leafy vegetables, vegetables and fruits exposed to direct deposition of airborne pollutants, vegetables and fruits protected from direct deposition, and grains. Livestock feeds are also tabulated in four categories: pasture, grain, hay, and silage. Pasture was estimated by a material balance of cattle and sheep inventories, forage feed requirements, and reported harvested forage. Cattle (Bos spp.), sheep (Ovis aries), goat (Capra hircus), hog (Sus scrofa), chicken (Gallus domesticus), and turkey (Meleagris gallopavo) inventories or sales are also tabulated in the data libraries and can be used to provide estimates of meat, eggs, and milk production. Honey production also is given. Population, irrigation, and meteorological information are also listed

  17. Gene Delivery into Plant Cells for Recombinant Protein Production

    Directory of Open Access Journals (Sweden)

    Qiang Chen

    2015-01-01

    Full Text Available Recombinant proteins are primarily produced from cultures of mammalian, insect, and bacteria cells. In recent years, the development of deconstructed virus-based vectors has allowed plants to become a viable platform for recombinant protein production, with advantages in versatility, speed, cost, scalability, and safety over the current production paradigms. In this paper, we review the recent progress in the methodology of agroinfiltration, a solution to overcome the challenge of transgene delivery into plant cells for large-scale manufacturing of recombinant proteins. General gene delivery methodologies in plants are first summarized, followed by extensive discussion on the application and scalability of each agroinfiltration method. New development of a spray-based agroinfiltration and its application on field-grown plants is highlighted. The discussion of agroinfiltration vectors focuses on their applications for producing complex and heteromultimeric proteins and is updated with the development of bridge vectors. Progress on agroinfiltration in Nicotiana and non-Nicotiana plant hosts is subsequently showcased in context of their applications for producing high-value human biologics and low-cost and high-volume industrial enzymes. These new advancements in agroinfiltration greatly enhance the robustness and scalability of transgene delivery in plants, facilitating the adoption of plant transient expression systems for manufacturing recombinant proteins with a broad range of applications.

  18. Metabolic modelling of polyhydroxyalkanoate copolymers production by mixed microbial cultures

    Directory of Open Access Journals (Sweden)

    Reis Maria AM

    2008-07-01

    Full Text Available Abstract Background This paper presents a metabolic model describing the production of polyhydroxyalkanoate (PHA copolymers in mixed microbial cultures, using mixtures of acetic and propionic acid as carbon source material. Material and energetic balances were established on the basis of previously elucidated metabolic pathways. Equations were derived for the theoretical yields for cell growth and PHA production on mixtures of acetic and propionic acid as functions of the oxidative phosphorylation efficiency, P/O ratio. The oxidative phosphorylation efficiency was estimated from rate measurements, which in turn allowed the estimation of the theoretical yield coefficients. Results The model was validated with experimental data collected in a sequencing batch reactor (SBR operated under varying feeding conditions: feeding of acetic and propionic acid separately (control experiments, and the feeding of acetic and propionic acid simultaneously. Two different feast and famine culture enrichment strategies were studied: (i either with acetate or (ii with propionate as carbon source material. Metabolic flux analysis (MFA was performed for the different feeding conditions and culture enrichment strategies. Flux balance analysis (FBA was used to calculate optimal feeding scenarios for high quality PHA polymers production, where it was found that a suitable polymer would be obtained when acetate is fed in excess and the feeding rate of propionate is limited to ~0.17 C-mol/(C-mol.h. The results were compared with published pure culture metabolic studies. Conclusion Acetate was more conducive toward the enrichment of a microbial culture with higher PHA storage fluxes and yields as compared to propionate. The P/O ratio was not only influenced by the selected microbial culture, but also by the carbon substrate fed to each culture, where higher P/O ratio values were consistently observed for acetate than propionate. MFA studies suggest that when mixtures of

  19. Adaptive Regulation of Osteopontin Production by Dendritic Cells Through the Bidirectional Interaction With Mesenchymal Stromal Cells

    Directory of Open Access Journals (Sweden)

    Sara Scutera

    2018-06-01

    Full Text Available Mesenchymal stromal cells (MSCs exert immunosuppressive effects on immune cells including dendritic cells (DCs. However, many details of the bidirectional interaction of MSCs with DCs are still unsolved and information on key molecules by which DCs can modulate MSC functions is limited. Here, we report that osteopontin (OPN, a cytokine involved in homeostatic and pathophysiologic responses, is constitutively expressed by DCs and regulated in the DC/MSC cocultures depending on the activation state of MSCs. Resting MSCs promoted OPN production, whereas the production of OPN was suppressed when MSCs were activated by proinflammatory cytokines (i.e., TNF-α, IL-6, and IL-1β. OPN induction required cell-to-cell contact, mediated at least in part, by β1 integrin (CD29. Conversely, activated MSCs inhibited the release of OPN via the production of soluble factors with a major role played by Prostaglandin E2 (PGE2. Accordingly, pretreatment with indomethacin significantly abrogated the MSC-mediated suppression of OPN while the direct addition of exogenous PGE2 inhibited OPN production by DCs. Furthermore, DC-conditioned medium promoted osteogenic differentiation of MSCs with a concomitant inhibition of adipogenesis. These effects were paralleled by the repression of the adipogenic markers PPARγ, adiponectin, and FABP4, and induction of the osteogenic markers alkaline phosphatase, RUNX2, and of the bone-anabolic chemokine CCL5. Notably, blocking OPN activity with RGD peptides or with an antibody against CD29, one of the OPN receptors, prevented the effects of DC-conditioned medium on MSC differentiation and CCL5 induction. Because MSCs have a key role in maintenance of bone marrow (BM hematopoietic stem cell niche through reciprocal regulation with immune cells, we investigated the possible MSC/DC interaction in human BM by immunohistochemistry. Although DCs (CD1c+ are a small percentage of BM cells, we demonstrated colocalization of CD271+ MSCs with

  20. Histone deacetylase inhibitors restore IL-10 expression in lipopolysaccharide-induced cell inflammation and reduce IL-1β and IL-6 production in breast silicone implant in C57BL/6J wild-type murine model.

    Science.gov (United States)

    Di Liddo, Rosa; Valente, Sergio; Taurone, Samanta; Zwergel, Clemens; Marrocco, Biagina; Turchetta, Rosaria; Conconi, Maria Teresa; Scarpa, Carlotta; Bertalot, Thomas; Schrenk, Sandra; Mai, Antonello; Artico, Marco

    2016-01-20

    Among epigenetic enzymes, histone deacetylases (HDACs) are responsible for regulating the expression of an extensive array of genes by reversible deacetylation of nuclear histones as well as a large number of non-histone proteins. Initially proposed for cancer therapy, recently the interest for HDAC inhibitors (HDACi) as orally active, safe, and anti-inflammatory agents is rising due to their ability in reducing the severity of inflammatory and autoimmune diseases. In particular, selective HDAC3, HDAC6, and HDAC8 inhibitors have been described to downregulate the expression of pro-inflammatory cytokines (TNF-α, TGF-β, IL-1β, and IL-6). Herein, using KB31, C2C12, and 3T3-J2 cell lines, we demonstrated that, under lipopolysaccharide-induced in vitro inflammation, HDAC3/6/8 inhibitor MC2625 and HDAC6-selective inhibitor MC2780 were effective at a concentration of 30 ng/mL to downregulate mRNA expression of pro-inflammatory cytokines (IL-1β and IL-6) and to promote the transcription of IL-10 gene, without affecting the cell viability. Afterwards, we investigated by immunohistochemistry the activity of MC2625 and MC2780 at a concentration of 60 ng/kg animal weight to regulate silicone-triggered immune response in C57BL/6J female mice. Our findings evidenced the ability of such inhibitors to reduce host inflammation in silicone implants promoting a thickness reduction of peri-implant fibrous capsule, upregulating IL-10 expression, and reducing the production of both IL-1β and IL-6. These results underline the potential application of MC2625 and MC2780 in inflammation-related diseases.

  1. Developing and modelling of ohmic heating for solid food products

    DEFF Research Database (Denmark)

    Feyissa, Aberham Hailu; Frosch, Stina

    Heating of solid foods using the conventional technologies is time-consuming due to the fact that heat transfer is limited by internal conduction within the product. This is a big challenge to food manufactures who wish to heat the product faster to the desired core temperature and to ensure more...... uniform quality across the product. Ohmic heating is one of the novel technologies potentially solving this problem by allowing volumetric heating of the product and thereby reducing or eliminating temperature gradients within the product. However, the application of ohmic heating for solid food products...... such as meat and seafood is not industrially utilized yet. Therefore, the aim of the current work is to model and develop the ohmic heating technology for heating of solid meat and seafood. A 3D mathematical model of coupled heat transfer and electric field during ohmic heating of meat products has been...

  2. Production system with process quality control: modelling and application

    Science.gov (United States)

    Tsou, Jia-Chi

    2010-07-01

    Over the past decade, there has been a great deal of research dedicated to the study of quality and the economics of production. In this article, we develop a dynamic model which is based on the hypothesis of a traditional economic production quantity model. Taguchi's cost of poor quality is used to evaluate the cost of poor quality in the dynamic production system. A practical case from the automotive industry, which uses the Six-sigma DMAIC methodology, is discussed to verify the proposed model. This study shows that there is an optimal value of quality investment to make the production system reach a reasonable quality level and minimise the production cost. Based on our model, the management can adjust its investment in quality improvement to generate considerable financial return.

  3. Three-dimensional decomposition models for carbon productivity

    International Nuclear Information System (INIS)

    Meng, Ming; Niu, Dongxiao

    2012-01-01

    This paper presents decomposition models for the change in carbon productivity, which is considered a key indicator that reflects the contributions to the control of greenhouse gases. Carbon productivity differential was used to indicate the beginning of decomposition. After integrating the differential equation and designing the Log Mean Divisia Index equations, a three-dimensional absolute decomposition model for carbon productivity was derived. Using this model, the absolute change of carbon productivity was decomposed into a summation of the absolute quantitative influences of each industrial sector, for each influence factor (technological innovation and industrial structure adjustment) in each year. Furthermore, the relative decomposition model was built using a similar process. Finally, these models were applied to demonstrate the decomposition process in China. The decomposition results reveal several important conclusions: (a) technological innovation plays a far more important role than industrial structure adjustment; (b) industry and export trade exhibit great influence; (c) assigning the responsibility for CO 2 emission control to local governments, optimizing the structure of exports, and eliminating backward industrial capacity are highly essential to further increase China's carbon productivity. -- Highlights: ► Using the change of carbon productivity to measure a country's contribution. ► Absolute and relative decomposition models for carbon productivity are built. ► The change is decomposed to the quantitative influence of three-dimension. ► Decomposition results can be used for improving a country's carbon productivity.

  4. Bioelectricity Production from Microalgae-Microbial Fuel Cell Technology (MMFC

    Directory of Open Access Journals (Sweden)

    da Costa Carlito

    2018-01-01

    Full Text Available Microbial fuel cell is an ecological innovative technology producing bioelectricity by utilizing microbes activity. Substituent energy is produced by changing the chemical energy to electrical energy through the catalytic reaction of microorganism. The research aims to find out the potency of bioelectricity produced by microalgae microbial fuel cell technology by utilizing the combination of tapioca wastewater and microalgae cultivation. This research is conducted through the ingredients preparation stage – microalgae culture, wastewater characterization, membrane and graphite activation, and the providing of other supporting equipment. The next stage is the MMFC arrangement, while the last one is bioelectricity measurement. The result of optimal bioelectricity production on the comparison of electrode 2 : 2, the power density is 44,33 mW/m2 on day 6, meanwhile, on that of 1 : 1, 20,18 mW/m2 power density on day 1 is obtained. It shows that bioelectricity can be produced from the combination of tapioca wastewater and microalgae culture through the microalgae-microbial fuel cell (MMFC technology.This research is expected to be a reference for the next research particularly the one that observes the utilizing of microalgae as the part of new and renewable energy sources.

  5. Lattice Model for Production of Gas

    KAUST Repository

    Marder, M.; Eftekhari, Behzad; Patzek, Tadeusz

    2017-01-01

    We define a lattice model for rock, absorbers, and gas that makes it possible to examine the flow of gas to a complicated absorbing boundary over long periods of time. The motivation is to deduce the geometry of the boundary from the time history

  6. Numerical Modeling of Rotary Kiln Productivity Increase

    NARCIS (Netherlands)

    Romero-Valle, M.A.; Pisaroni, M.; Van Puyvelde, D.; Lahaye, D.J.P.; Sadi, R.

    2013-01-01

    Rotary kilns are used in many industrial processes ranging from cement manufacturing to waste incineration. The operating conditions vary widely depending on the process. While there are many models available within the literature and industry, the wide range of operating conditions justifies

  7. Putting mechanisms into crop production models.

    Science.gov (United States)

    Boote, Kenneth J; Jones, James W; White, Jeffrey W; Asseng, Senthold; Lizaso, Jon I

    2013-09-01

    Crop growth models dynamically simulate processes of C, N and water balance on daily or hourly time-steps to predict crop growth and development and at season-end, final yield. Their ability to integrate effects of genetics, environment and crop management have led to applications ranging from understanding gene function to predicting potential impacts of climate change. The history of crop models is reviewed briefly, and their level of mechanistic detail for assimilation and respiration, ranging from hourly leaf-to-canopy assimilation to daily radiation-use efficiency is discussed. Crop models have improved steadily over the past 30-40 years, but much work remains. Improvements are needed for the prediction of transpiration response to elevated CO₂ and high temperature effects on phenology and reproductive fertility, and simulation of root growth and nutrient uptake under stressful edaphic conditions. Mechanistic improvements are needed to better connect crop growth to genetics and to soil fertility, soil waterlogging and pest damage. Because crop models integrate multiple processes and consider impacts of environment and management, they have excellent potential for linking research from genomics and allied disciplines to crop responses at the field scale, thus providing a valuable tool for deciphering genotype by environment by management effects. © 2013 John Wiley & Sons Ltd.

  8. Effect of microwell chip structure on cell microsphere production of various animal cells.

    Science.gov (United States)

    Sakai, Yusuke; Yoshida, Shirou; Yoshiura, Yukiko; Mori, Rhuhei; Tamura, Tomoko; Yahiro, Kanji; Mori, Hideki; Kanemura, Yonehiro; Yamasaki, Mami; Nakazawa, Kohji

    2010-08-01

    The formation of three-dimensional cell microspheres such as spheroids, embryoid bodies, and neurospheres has attracted attention as a useful culture technique. In this study, we investigated a technique for effective cell microsphere production by using specially prepared microchip. The basic chip design was a multimicrowell structure in triangular arrangement within a 100-mm(2) region in the center of a polymethylmethacrylate (PMMA) plate (24x24 mm(2)), the surface of which was modified with polyethylene glycol (PEG) to render it nonadhesive to cells. We also designed six similar chips with microwell diameters of 200, 300, 400, 600, 800, and 1000 microm to investigate the effect of the microwell diameter on the cell microsphere diameter. Rat hepatocytes, HepG2 cells, mouse embryonic stem (ES) cells, and mouse neural progenitor/stem (NPS) cells formed hepatocyte spheroids, HepG2 spheroids, embryoid bodies, and neurospheres, respectively, in the microwells within 5 days of culture. For all the cells, a single microsphere was formed in each microwell under all the chip conditions, and such microsphere configurations remained throughout the culture period. Furthermore, the microsphere diameters of each type of cell were strongly positively correlated with the microwell diameters of the chips, suggesting that microsphere diameter can be factitiously controlled by using different chip conditions. Thus, this chip technique is a promising cellular platform for tissue engineering or regenerative medicine research, pharmacological and toxicological studies, and fundamental studies in cell biology. Copyright 2010 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  9. Arecoline decreases interleukin-6 production and induces apoptosis and cell cycle arrest in human basal cell carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Li-Wen [Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Hsieh, Bau-Shan; Cheng, Hsiao-Ling [Department of Biochemistry, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Hu, Yu-Chen [Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Chang, Wen-Tsan [Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Division of Hepatobiliarypancreatic Surgery, Department of Surgery, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan (China); Chang, Kee-Lung, E-mail: Chang.KeeLung@msa.hinet.net [Department of Biochemistry, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China)

    2012-01-15

    Arecoline, the most abundant areca alkaloid, has been reported to decrease interleukin-6 (IL-6) levels in epithelial cancer cells. Since IL-6 overexpression contributes to the tumorigenic potency of basal cell carcinoma (BCC), this study was designed to investigate whether arecoline altered IL-6 expression and its downstream regulation of apoptosis and the cell cycle in cultured BCC-1/KMC cells. BCC-1/KMC cells and a human keratinocyte cell line, HaCaT, were treated with arecoline at concentrations ranging from 10 to 100 μg/ml, then IL-6 production and expression of apoptosis- and cell cycle progress-related factors were examined. After 24 h exposure, arecoline inhibited BCC-1/KMC cell growth and decreased IL-6 production in terms of mRNA expression and protein secretion, but had no effect on HaCaT cells. Analysis of DNA fragmentation and chromatin condensation showed that arecoline induced apoptosis of BCC-1/KMC cells in a dose-dependent manner, activated caspase-3, and decreased expression of the anti-apoptotic protein Bcl-2. In addition, arecoline induced progressive and sustained accumulation of BCC-1/KMC cells in G2/M phase as a result of reducing checkpoint Cdc2 activity by decreasing Cdc25C phosphatase levels and increasing p53 levels. Furthermore, subcutaneous injection of arecoline led to decreased BCC-1/KMC tumor growth in BALB/c mice by inducing apoptosis. This study demonstrates that arecoline has potential for preventing BCC tumorigenesis by reducing levels of the tumor cell survival factor IL-6, increasing levels of the tumor suppressor factor p53, and eliciting cell cycle arrest, followed by apoptosis. Highlights: ► Arecoline has potential to prevent against basal cell carcinoma tumorigenesis. ► It has more effectiveness on BCC as compared with a human keratinocyte cell line. ► Mechanisms involved including reducing tumor cells’ survival factor IL-6, ► Decreasing Cdc25C phosphatase, enhancing tumor suppressor factor p53, ► Eliciting G2/M

  10. Hydrogen production and purification for fuel cell applications

    Science.gov (United States)

    Chin, Soo Yin

    The increased utilization of proton-exchange membrane (PEM) fuel cells as an alternative to internal combustion engines is expected to increase the demand for hydrogen, which is used as the energy source in these systems. Currently, production of hydrogen for fuel cells is primarily achieved via steam reforming, partial oxidation or autothermal reforming of natural gas, or steam reforming of methanol. However, in all of these processes CO is a by-product that must be subsequently removed due to its adverse effects on the Pt-based electrocatalysts of the PEM fuel cell. Our efforts have focused on production of CO-free hydrogen via catalytic decomposition of hydrocarbons and purification of H2 via the preferential oxidation of CO. The catalytic decomposition of hydrocarbons is an attractive alternative for the production of H2. Previous studies utilizing methane have shown that this approach can indeed produce CO-free hydrogen, with filamentous carbon formed as the by-product and deposited on the catalyst. We have further extended this approach to the decomposition of ethane. In addition to hydrogen and filamentous carbon however, methane is also formed in this case as a by-product. Studies conducted at different temperatures and space velocities suggest that hydrogen is the primary product while methane is formed in a secondary step. Ni/SiO2 catalysts are active for ethane decomposition at temperatures above 500°C. Although the yield of hydrogen increases with temperature, the catalyst deactivation rate also accelerates at higher temperatures. The preferential oxidation of CO is currently used for the purification of CO-contaminated hydrogen streams due to its efficiency and simplicity. Conventional Pt catalysts used for this reaction have been shown to effectively remove CO, but have limited selectivity (i.e., substantial amounts of H 2 also react with O2). Our work focused on alternative catalytic materials, such as Ru and bimetallic Ru-based catalysts (Pt-Ru, Ru

  11. Application of response surface methodology to maximize the productivity of scalable automated human embryonic stem cell manufacture.

    Science.gov (United States)

    Ratcliffe, Elizabeth; Hourd, Paul; Guijarro-Leach, Juan; Rayment, Erin; Williams, David J; Thomas, Robert J

    2013-01-01

    Commercial regenerative medicine will require large quantities of clinical-specification human cells. The cost and quality of manufacture is notoriously difficult to control due to highly complex processes with poorly defined tolerances. As a step to overcome this, we aimed to demonstrate the use of 'quality-by-design' tools to define the operating space for economic passage of a scalable human embryonic stem cell production method with minimal cell loss. Design of experiments response surface methodology was applied to generate empirical models to predict optimal operating conditions for a unit of manufacture of a previously developed automatable and scalable human embryonic stem cell production method. Two models were defined to predict cell yield and cell recovery rate postpassage, in terms of the predictor variables of media volume, cell seeding density, media exchange and length of passage. Predicted operating conditions for maximized productivity were successfully validated. Such 'quality-by-design' type approaches to process design and optimization will be essential to reduce the risk of product failure and patient harm, and to build regulatory confidence in cell therapy manufacturing processes.

  12. Compact hydrogen production systems for solid polymer fuel cells

    Science.gov (United States)

    Ledjeff-Hey, K.; Formanski, V.; Kalk, Th.; Roes, J.

    Generally there are several ways to produce hydrogen gas from carbonaceous fuels like natural gas, oil or alcohols. Most of these processes are designed for large-scale industrial production and are not suitable for a compact hydrogen production system (CHYPS) in the power range of 1 kW. In order to supply solid polymer fuel cells (SPFC) with hydrogen, a compact fuel processor is required for mobile applications. The produced hydrogen-rich gas has to have a low level of harmful impurities; in particular the carbon monoxide content has to be lower than 20 ppmv. Integrating the reaction step, the gas purification and the heat supply leads to small-scale hydrogen production systems. The steam reforming of methanol is feasible at copper catalysts in a low temperature range of 200-350°C. The combination of a small-scale methanol reformer and a metal membrane as purification step forms a compact system producing high-purity hydrogen. The generation of a SPFC hydrogen fuel gas can also be performed by thermal or catalytic cracking of liquid hydrocarbons such as propane. At a temperature of 900°C the decomposition of propane into carbon and hydrogen takes place. A fuel processor based on this simple concept produces a gas stream with a hydrogen content of more than 90 vol.% and without CO and CO2.

  13. [Safety monitoring of cell-based medicinal products (CBMPs)].

    Science.gov (United States)

    Funk, Markus B; Frech, Marion; Spranger, Robert; Keller-Stanislawski, Brigitte

    2015-11-01

    Cell-based medicinal products (CBMPs), a category of advanced-therapy medicinal products (ATMPs), are authorised for the European market by the European Commission by means of the centralized marketing authorisation. By conforming to the German Medicinal Products Act (Sec. 4b AMG), national authorisation can be granted by the Paul-Ehrlich-Institut in Germany exclusively for ATMPs not based on a routine manufacturing procedure. In both procedures, quality, efficacy, and safety are evaluated and the risk-benefit balance is assessed. For the centralised procedure, mainly controlled clinical trial data must be submitted, whereas the requirements for national procedures could be modified corresponding to the stage of development of the ATMP. After marketing authorization, the marketing authorization/license holder is obligated to report all serious adverse reactions to the competent authority and to provide periodic safety update reports. If necessary, post-authorization safety studies could be imposed. On the basis of these regulatory measures, the safety of advanced therapies can be monitored and improved.

  14. A stochastic surplus production model in continuous time

    DEFF Research Database (Denmark)

    Pedersen, Martin Wæver; Berg, Casper Willestofte

    2017-01-01

    surplus production model in continuous time (SPiCT), which in addition to stock dynamics also models the dynamics of the fisheries. This enables error in the catch process to be reflected in the uncertainty of estimated model parameters and management quantities. Benefits of the continuous-time state......Surplus production modelling has a long history as a method for managing data-limited fish stocks. Recent advancements have cast surplus production models as state-space models that separate random variability of stock dynamics from error in observed indices of biomass. We present a stochastic......-space model formulation include the ability to provide estimates of exploitable biomass and fishing mortality at any point in time from data sampled at arbitrary and possibly irregular intervals. We show in a simulation that the ability to analyse subannual data can increase the effective sample size...

  15. Technology Model of Aquaculture Production System

    Science.gov (United States)

    Hor, K. W.; Salleh, S. M.; Abdullah; Ezree, Mohd; Zaman, I.; Hatta, M. H.; Ahmad, S.; Ismail, A. E.; Mahmud, W. A. W.

    2017-10-01

    The high market demand has led to the rapid growth in fish farming. The young generation are inexperienced in determining the estimated results of fish farming and the preparation of fish pond during the period of fish farming. These need a complete guide as their reference which includes the knowledge of fish farming. The main objective of this project is to develop a practical design of real pond appropriate with aquaculture technology and fish farming production. There are three parts of study in this project which include fish farming cage, growth of fish and water quality of fish farming pond. Few of experiments were carried out involved the collection data in terms of growth of fish and parameters of water quality.

  16. Phase Equilibrium Modeling for Shale Production Simulation

    DEFF Research Database (Denmark)

    Sandoval Lemus, Diego Rolando

    is obtained for hydrocarbon mixtures. Such behavior is mainly caused by compositional changes in the bulk phase due to selective adsorption of the heavier components onto the rock, while the change in bubble point pressure is mainly due to capillary pressure. This study has developed several robust......Production of oil and gas from shale reservoirs has gained more attention in the past few decades due to its increasing economic feasibility and the size of potential sources around the world. Shale reservoirs are characterized by a more tight nature in comparison with conventional reservoirs......, having pore size distributions ranging in the nanometer scale. Such a confined nature introduces new challenges in the fluid phase behavior. High capillary forces can be experienced between the liquid and vapor, and selective adsorption of components onto the rock becomes relevant. The impact...

  17. Modeling of nitrous oxide production by autotrophic ammonia-oxidizing bacteria with multiple production pathways.

    Science.gov (United States)

    Ni, Bing-Jie; Peng, Lai; Law, Yingyu; Guo, Jianhua; Yuan, Zhiguo

    2014-04-01

    Autotrophic ammonia oxidizing bacteria (AOB) have been recognized as a major contributor to N2O production in wastewater treatment systems. However, so far N2O models have been proposed based on a single N2O production pathway by AOB, and there is still a lack of effective approach for the integration of these models. In this work, an integrated mathematical model that considers multiple production pathways is developed to describe N2O production by AOB. The pathways considered include the nitrifier denitrification pathway (N2O as the final product of AOB denitrification with NO2(-) as the terminal electron acceptor) and the hydroxylamine (NH2OH) pathway (N2O as a byproduct of incomplete oxidation of NH2OH to NO2(-)). In this model, the oxidation and reduction processes are modeled separately, with intracellular electron carriers introduced to link the two types of processes. The model is calibrated and validated using experimental data obtained with two independent nitrifying cultures. The model satisfactorily describes the N2O data from both systems. The model also predicts shifts of the dominating pathway at various dissolved oxygen (DO) and nitrite levels, consistent with previous hypotheses. This unified model is expected to enhance our ability to predict N2O production by AOB in wastewater treatment systems under varying operational conditions.

  18. A model for marketing planning for new products

    DEFF Research Database (Denmark)

    Martensen, Anne

    1993-01-01

    awareness model. The model can be used to generate improved marketing plans. In this connection, it is important that the model includes the marketing variables, for it is only in this way that the model can be used for marketing plan optimization. It is predicted that a future direction of development...... and use of sales forecasting models for new products will be within optimization of the marketing plan for launching a new product, and not only as a tool for forecasting sales for just one marketing plan....

  19. A Health Production Model with Endogenous Retirement

    Science.gov (United States)

    Galama, Titus; Kapteyn, Arie; Fonseca, Raquel; Michaud, Pierre-Carl

    2012-01-01

    We formulate a stylized structural model of health, wealth accumulation and retirement decisions building on the human capital framework of health and derive analytic solutions for the time paths of consumption, health, health investment, savings and retirement. We argue that the literature has been unnecessarily restrictive in assuming that health is always at the “optimal” health level. Exploring the properties of corner solutions we find that advances in population health decrease the retirement age, while at the same time individuals retire when their health has deteriorated. This potentially explains why retirees point to deteriorating health as an important reason for early retirement, while retirement ages have continued to fall in the developed world, despite continued improvements in population health and mortality. In our model, workers with higher human capital invest more in health and because they stay healthier retire later than those with lower human capital whose health deteriorates faster. PMID:22888062

  20. Production of prostate-specific antigen by a breast cancer cell line, Sk-Br-3

    International Nuclear Information System (INIS)

    Kamali Sarvestani, E.; Ghaderi, A.

    2002-01-01

    Prostate-specific antigen is a 33-KDa serine protease that is produced predominantly by prostate epithelium. However, it has been shown that about 30-40% of female breast tumors produce prostate-specific antigen and its production is associated with the presence of estrogen and progesterone receptors. We have now developed a new tissue culture system to study prostate-specific antigen production in breast cancer and its association with prognostic factors such as progesterone receptor and c-erbB-2. For this purpose we investigated the ability of prostate-specific antigen production in five different cell lines, including two breast cancer cell lines, Sk-Br-3 and MDA-MB-453. The prostate-specific antigen in tissue culture supernatant and cytoplasm of the Sk-Br-3 cell line was detected by western blotting and immunoperoxidase, respectively. Furthermore, we found lower expression of c-erbB-2 in Sk-Br-3 than non-prostate-specific antigen producer breast cancer cell line, MDA-MB-453. Progesterone receptor was expressed by both prostate-specific antigen-positive and -negative cell lines and only the intensity of staining and the number of positive cells in Sk-Br-3 population was higher than MDA-MB-453. According to our findings prostate-specific antigen can be considered as a good prognostic factor in breast cancer and we suggest that these two cell lines are a good in vitro model to study the relationship of different breast cancer prognostic factors and their regulations

  1. Sustainability Product Properties in Building Information Models

    Science.gov (United States)

    2012-09-01

    preferred car- pool parking spots, preferred low-emitting/fuel-efficient vehicle parking spots, bike racks and telecommuting as options to promote good...most part, these have not been in a computable form. Fallon then stressed the importance of a common conceptual framework, using the IFC model...organizations would be formed with the help of Mr. Kalin. He stressed the goal of the project was to create templates that would be free to use

  2. Study of growth kinetic and modeling of ethanol production by ...

    African Journals Online (AJOL)

    ... coefficient (0.96299). Based on Leudking-Piret model, it could be concluded that ethanol batch fermentation is a non-growth associated process. Key words: Kinetic parameters, simulation, cell growth, ethanol, Saccharomyces cerevisiae.

  3. Macrophage secretory products selectively stimulate dermatan sulfate proteoglycan production in cultured arterial smooth muscle cells

    International Nuclear Information System (INIS)

    Edwards, I.J.; Wagner, W.D.; Owens, R.T.

    1990-01-01

    Arterial dermatan sulfate proteoglycan has been shown to increase with atherosclerosis progression, but factors responsible for this increase are unknown. To test the hypothesis that smooth muscle cell proteoglycan synthesis may be modified by macrophage products, pigeon arterial smooth muscle cells were exposed to the media of either cholesteryl ester-loaded pigeon peritoneal macrophages or a macrophage cell line P388D1. Proteoglycans radiolabeled with [35S]sulfate and [3H]serine were isolated from culture media and smooth muscle cells and purified following precipitation with 1-hexadecylpyridinium chloride and chromatography. Increasing concentrations of macrophage-conditioned media were associated with a dose-response increase in [35S]sulfate incorporation into secreted proteoglycans, but there was no change in cell-associated proteoglycans. Incorporation of [3H]serine into total proteoglycan core proteins was not significantly different (5.2 X 10(5) dpm and 5.5 X 10(5) disintegrations per minute (dpm) in control and conditioned media-treated cultures, respectively), but selective effects were observed on individual proteoglycan types. Twofold increases in dermatan sulfate proteoglycan and limited degradation of chondroitin sulfate proteoglycan were apparent based on core proteins separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Immunoinhibition studies indicated that interleukin-1 was involved in the modulation of proteoglycan synthesis by macrophage-conditioned media. These data provide support for the role of macrophages in alteration of the matrix proteoglycans synthesized by smooth muscle cells and provide a mechanism to account for the reported increased dermatan sulfate/chondroitin sulfate ratios in the developing atherosclerotic lesion

  4. A Product Development Decision Model for Cockpit Weather Information Systems

    Science.gov (United States)

    Sireli, Yesim; Kauffmann, Paul; Gupta, Surabhi; Kachroo, Pushkin

    2003-01-01

    There is a significant market demand for advanced cockpit weather information products. However, it is unclear how to identify the most promising technological options that provide the desired mix of consumer requirements by employing feasible technical systems at a price that achieves market success. This study develops a unique product development decision model that employs Quality Function Deployment (QFD) and Kano's model of consumer choice. This model is specifically designed for exploration and resolution of this and similar information technology related product development problems.

  5. A Product Development Decision Model for Cockpit Weather Information System

    Science.gov (United States)

    Sireli, Yesim; Kauffmann, Paul; Gupta, Surabhi; Kachroo, Pushkin; Johnson, Edward J., Jr. (Technical Monitor)

    2003-01-01

    There is a significant market demand for advanced cockpit weather information products. However, it is unclear how to identify the most promising technological options that provide the desired mix of consumer requirements by employing feasible technical systems at a price that achieves market success. This study develops a unique product development decision model that employs Quality Function Deployment (QFD) and Kano's model of consumer choice. This model is specifically designed for exploration and resolution of this and similar information technology related product development problems.

  6. Geometric Modeling and Reasoning of Human-Centered Freeform Products

    CERN Document Server

    Wang, Charlie C L

    2013-01-01

    The recent trend in user-customized product design requires the shape of products to be automatically adjusted according to the human body’s shape, so that people will feel more comfortable when wearing these products.  Geometric approaches can be used to design the freeform shape of products worn by people, which can greatly improve the efficiency of design processes in various industries involving customized products (e.g., garment design, toy design, jewel design, shoe design, and design of medical devices, etc.). These products are usually composed of very complex geometric shapes (represented by free-form surfaces), and are not driven by a parameter table but a digital human model with free-form shapes or part of human bodies (e.g., wrist, foot, and head models).   Geometric Modeling and Reasoning of Human-Centered Freeform Products introduces the algorithms of human body reconstruction, freeform product modeling, constraining and reconstructing freeform products, and shape optimization for improving...

  7. Modeling effects of DO and SRT on activated sludge decay and production.

    Science.gov (United States)

    Liu, Guoqiang; Wang, Jianmin

    2015-09-01

    The effect of dissolved oxygen (DO) on the endogenous decay of active heterotrophic biomass and the hydrolysis of cell debris were studied. With the inclusion of a hydrolysis process for the cell debris, mathematical models that are capable of quantifying the effects of DO and sludge retention time (SRT) on concentrations of active biomass and cell debris in activated sludge are presented. By modeling the biomass cultivated with unlimited DO, the values of endogenous decay coefficient for heterotrophic biomass, the hydrolysis constant of cell debris, and the fraction of decayed biomass that became cell debris were determined to be 0.38 d(-1), 0.013 d(-1), and 0.28, respectively. Results from modeling the biomass cultivated under different DO conditions suggested that the experimental low DO (∼0.2 mg/L) did not inhibit the endogenous decay of heterotrophic biomass, but significantly inhibited the hydrolysis of cell debris with a half-velocity constant value of 2.1 mg/L. Therefore, the increase in sludge production with low DO was mainly contributed by cell debris rather than the active heterotrophic biomass. Maximizing sludge production during aerobic wastewater treatment could reduce aeration energy consumption and improve biogas energy recovery potential. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Bags versus flasks: a comparison of cell culture systems for the production of dendritic cell-based immunotherapies.

    Science.gov (United States)

    Fekete, Natalie; Béland, Ariane V; Campbell, Katie; Clark, Sarah L; Hoesli, Corinne A

    2018-04-19

    In recent years, cell-based therapies targeting the immune system have emerged as promising strategies for cancer treatment. This review summarizes manufacturing challenges related to production of antigen presenting cells as a patient-tailored cancer therapy. Understanding cell-material interactions is essential because in vitro cell culture manipulations to obtain mature antigen-producing cells can significantly alter their in vivo performance. Traditional antigen-producing cell culture protocols often rely on cell adhesion to surface-treated hydrophilic polystyrene flasks. More recent commercial and investigational cancer immunotherapy products were manufactured using suspension cell culture in closed hydrophobic fluoropolymer bags. The shift to closed cell culture systems can decrease risks of contamination by individual operators, as well as facilitate scale-up and automation. Selecting closed cell culture bags over traditional open culture systems entails different handling procedures and processing controls, which can affect product quality. Changes in culture vessels also entail changes in vessel materials and geometry, which may alter the cell microenvironment and resulting cell fate decisions. Strategically designed culture systems will pave the way for the generation of more sophisticated and highly potent cell-based cancer vaccines. As an increasing number of cell-based therapies enter the clinic, the selection of appropriate cell culture vessels and materials becomes a critical consideration that can impact the therapeutic efficacy of the product, and hence clinical outcomes and patient quality of life. © 2018 The Authors Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

  9. Acrylamide induces accelerated endothelial aging in a human cell model.

    Science.gov (United States)

    Sellier, Cyril; Boulanger, Eric; Maladry, François; Tessier, Frédéric J; Lorenzi, Rodrigo; Nevière, Rémi; Desreumaux, Pierre; Beuscart, Jean-Baptiste; Puisieux, François; Grossin, Nicolas

    2015-09-01

    Acrylamide (AAM) has been recently discovered in food as a Maillard reaction product. AAM and glycidamide (GA), its metabolite, have been described as probably carcinogenic to humans. It is widely established that senescence and carcinogenicity are closely related. In vitro, endothelial aging is characterized by replicative senescence in which primary cells in culture lose their ability to divide. Our objective was to assess the effects of AAM and GA on human endothelial cell senescence. Human umbilical vein endothelial cells (HUVECs) cultured in vitro were used as model. HUVECs were cultured over 3 months with AAM or GA (1, 10 or 100 μM) until growth arrest. To analyze senescence, β-galactosidase activity and telomere length of HUVECs were measured by cytometry and semi-quantitative PCR, respectively. At all tested concentrations, AAM or GA reduced cell population doubling compared to the control condition (p < 0.001). β-galactosidase activity in endothelial cells was increased when exposed to AAM (≥10 μM) or GA (≥1 μM) (p < 0.05). AAM (≥10 μM) or GA (100 μM) accelerated telomere shortening in HUVECs (p < 0.05). In conclusion, in vitro chronic exposure to AAM or GA at low concentrations induces accelerated senescence. This result suggests that an exposure to AAM might contribute to endothelial aging. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Modeling Substrate Utilization, Metabolite Production, and Uranium Immobilization in Shewanella oneidensis Biofilms

    Directory of Open Access Journals (Sweden)

    Ryan S. Renslow

    2017-06-01

    Full Text Available In this study, we developed a two-dimensional mathematical model to predict substrate utilization and metabolite production rates in Shewanella oneidensis MR-1 biofilm in the presence and absence of uranium (U. In our model, lactate and fumarate are used as the electron donor and the electron acceptor, respectively. The model includes the production of extracellular polymeric substances (EPS. The EPS bound to the cell surface and distributed in the biofilm were considered bound EPS (bEPS and loosely associated EPS (laEPS, respectively. COMSOL® Multiphysics finite element analysis software was used to solve the model numerically (model file provided in the Supplementary Material. The input variables of the model were the lactate, fumarate, cell, and EPS concentrations, half saturation constant for fumarate, and diffusion coefficients of the substrates and metabolites. To estimate unknown parameters and calibrate the model, we used a custom designed biofilm reactor placed inside a nuclear magnetic resonance (NMR microimaging and spectroscopy system and measured substrate utilization and metabolite production rates. From these data we estimated the yield coefficients, maximum substrate utilization rate, half saturation constant for lactate, stoichiometric ratio of fumarate and acetate to lactate and stoichiometric ratio of succinate to fumarate. These parameters are critical to predicting the activity of biofilms and are not available in the literature. Lastly, the model was used to predict uranium immobilization in S. oneidensis MR-1 biofilms by considering reduction and adsorption processes in the cells and in the EPS. We found that the majority of immobilization was due to cells, and that EPS was less efficient at immobilizing U. Furthermore, most of the immobilization occurred within the top 10 μm of the biofilm. To the best of our knowledge, this research is one of the first biofilm immobilization mathematical models based on experimental

  11. Hydrothermal decomposition of yeast cells for production of proteins and amino acids

    Energy Technology Data Exchange (ETDEWEB)

    Lamoolphak, Wiwat [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand); Goto, Motonobu [Department of Applied Chemistry and Biochemistry, Kumamoto University, Kumamoto 850-8555 (Japan); Sasaki, Mitsuru [Department of Applied Chemistry and Biochemistry, Kumamoto University, Kumamoto 850-8555 (Japan); Suphantharika, Manop [Department of Biotechnology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400 (Thailand); Muangnapoh, Chirakarn [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand); Prommuag, Chattip [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand); Shotipruk, Artiwan [Department of Chemical Engineering, Faculty of Engineering, Chulalongkorn University, Patumwan, Payathai Road, Bangkok 10330 (Thailand)]. E-mail: artiwan.s@chula.ac.th

    2006-10-11

    This study examines hydrothermal decomposition of Baker's yeast cells, used as a model for spent Brewer's yeast waste, into protein and amino acids. The reaction was carried out in a closed batch reactor at various temperatures between 100 and 250 deg. C. The reaction products were separated into water-soluble and solid residue. The results demonstrated that the amount of yeast residue decreased with increasing hydrolysis temperature. After 20 min reaction in water at 250 deg. C, 78% of yeast was decomposed. The highest amount of protein produced was also obtained at this condition and was found to be 0.16 mg/mg dry yeast. The highest amount of amino acids (0.063 mg/mg dry yeast) was found at the lowest temperature tested after 15 min. The hydrolysis product obtained at 200 deg. C was tested as a nutrient source for yeast growth. The growth of yeast cells in the culture medium containing 2 w/v% of this product was comparable to that of the cells grown in the medium containing commercial yeast extract at the same concentration. These results demonstrated the feasibility of using subcritical water to potentially decompose proteinaceous waste such as spent Brewer's yeast while recovering more useful products.

  12. Hydrothermal decomposition of yeast cells for production of proteins and amino acids

    International Nuclear Information System (INIS)

    Lamoolphak, Wiwat; Goto, Motonobu; Sasaki, Mitsuru; Suphantharika, Manop; Muangnapoh, Chirakarn; Prommuag, Chattip; Shotipruk, Artiwan

    2006-01-01

    This study examines hydrothermal decomposition of Baker's yeast cells, used as a model for spent Brewer's yeast waste, into protein and amino acids. The reaction was carried out in a closed batch reactor at various temperatures between 100 and 250 deg. C. The reaction products were separated into water-soluble and solid residue. The results demonstrated that the amount of yeast residue decreased with increasing hydrolysis temperature. After 20 min reaction in water at 250 deg. C, 78% of yeast was decomposed. The highest amount of protein produced was also obtained at this condition and was found to be 0.16 mg/mg dry yeast. The highest amount of amino acids (0.063 mg/mg dry yeast) was found at the lowest temperature tested after 15 min. The hydrolysis product obtained at 200 deg. C was tested as a nutrient source for yeast growth. The growth of yeast cells in the culture medium containing 2 w/v% of this product was comparable to that of the cells grown in the medium containing commercial yeast extract at the same concentration. These results demonstrated the feasibility of using subcritical water to potentially decompose proteinaceous waste such as spent Brewer's yeast while recovering more useful products

  13. Wind farm production prediction - The Zephyr model

    Energy Technology Data Exchange (ETDEWEB)

    Landberg, L. [Risoe National Lab., Wind Energy Dept., Roskilde (Denmark); Giebel, G. [Risoe National Lab., Wind Energy Dept., Roskilde (Denmark); Madsen, H. [IMM (DTU), Kgs. Lyngby (Denmark); Nielsen, T.S. [IMM (DTU), Kgs. Lyngby (Denmark); Joergensen, J.U. [Danish Meteorologisk Inst., Copenhagen (Denmark); Lauersen, L. [Danish Meteorologisk Inst., Copenhagen (Denmark); Toefting, J. [Elsam, Fredericia (DK); Christensen, H.S. [Eltra, Fredericia (Denmark); Bjerge, C. [SEAS, Haslev (Denmark)

    2002-06-01

    This report describes a project - funded by the Danish Ministry of Energy and the Environment - which developed a next generation prediction system called Zephyr. The Zephyr system is a merging between two state-of-the-art prediction systems: Prediktor of Risoe National Laboratory and WPPT of IMM at the Danish Technical University. The numerical weather predictions were generated by DMI's HIRLAM model. Due to technical difficulties programming the system, only the computational core and a very simple version of the originally very complex system were developed. The project partners were: Risoe, DMU, DMI, Elsam, Eltra, Elkraft System, SEAS and E2. (au)

  14. Air system in the hot cell for injectable radiopharmaceutical production: requirements for personnel and environment safety and protection of the product

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Fabio E.; Araujo, Elaine B., E-mail: fecampos@ipen.b, E-mail: ebaraujo@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    . Nevertheless, the application of clean room requirements in radioisotope laboratories in general and hot cells is technically not an easy task. The required negative pressure inside the hot cell depends on the operations to be performed inside the cell, on the type of radionuclide and their total activity. Hot cells works in negative pressure that ranges typically from 200 Pa to 500 Pa below room pressure. The new rules for radiopharmaceutical production will be soon published by ANVISA in order to regulate the GMP in this area. This make urgent the development of national models for hot cells that combines GMP and radioprotection concepts and attempt for the radiopharmaceutical process lines as in development at IPEN. (author)

  15. Air system in the hot cell for injectable radiopharmaceutical production: requirements for personnel and environment safety and protection of the product

    International Nuclear Information System (INIS)

    Campos, Fabio E.; Araujo, Elaine B.

    2009-01-01

    . Nevertheless, the application of clean room requirements in radioisotope laboratories in general and hot cells is technically not an easy task. The required negative pressure inside the hot cell depends on the operations to be performed inside the cell, on the type of radionuclide and their total activity. Hot cells works in negative pressure that ranges typically from 200 Pa to 500 Pa below room pressure. The new rules for radiopharmaceutical production will be soon published by ANVISA in order to regulate the GMP in this area. This make urgent the development of national models for hot cells that combines GMP and radioprotection concepts and attempt for the radiopharmaceutical process lines as in development at IPEN. (author)

  16. A nonlinear model of gold production in Malaysia

    Science.gov (United States)

    Ramli, Norashikin; Muda, Nora; Umor, Mohd Rozi

    2014-06-01

    Malaysia is a country which is rich in natural resources and one of it is a gold. Gold has already become an important national commodity. This study is conducted to determine a model that can be well fitted with the gold production in Malaysia from the year 1995-2010. Five nonlinear models are presented in this study which are Logistic model, Gompertz, Richard, Weibull and Chapman-Richard model. These model are used to fit the cumulative gold production in Malaysia. The best model is then selected based on the model performance. The performance of the fitted model is measured by sum squares error, root mean squares error, coefficient of determination, mean relative error, mean absolute error and mean absolute percentage error. This study has found that a Weibull model is shown to have significantly outperform compare to the other models. To confirm that Weibull is the best model, the latest data are fitted to the model. Once again, Weibull model gives the lowest readings at all types of measurement error. We can concluded that the future gold production in Malaysia can be predicted according to the Weibull model and this could be important findings for Malaysia to plan their economic activities.

  17. Modern Perspectives on Numerical Modeling of Cardiac Pacemaker Cell

    Science.gov (United States)

    Maltsev, Victor A.; Yaniv, Yael; Maltsev, Anna V.; Stern, Michael D.; Lakatta, Edward G.

    2015-01-01

    Cardiac pacemaking is a complex phenomenon that is still not completely understood. Together with experimental studies, numerical modeling has been traditionally used to acquire mechanistic insights in this research area. This review summarizes the present state of numerical modeling of the cardiac pacemaker, including approaches to resolve present paradoxes and controversies. Specifically we discuss the requirement for realistic modeling to consider symmetrical importance of both intracellular and cell membrane processes (within a recent “coupled-clock” theory). Promising future developments of the complex pacemaker system models include the introduction of local calcium control, mitochondria function, and biochemical regulation of protein phosphorylation and cAMP production. Modern numerical and theoretical methods such as multi-parameter sensitivity analyses within extended populations of models and bifurcation analyses are also important for the definition of the most realistic parameters that describe a robust, yet simultaneously flexible operation of the coupled-clock pacemaker cell system. The systems approach to exploring cardiac pacemaker function will guide development of new therapies, such as biological pacemakers for treating insufficient cardiac pacemaker function that becomes especially prevalent with advancing age. PMID:24748434

  18. Group 2 innate lymphoid cell production of IL-5 is regulated by NKT cells during influenza virus infection.

    Directory of Open Access Journals (Sweden)

    Stacey Ann Gorski

    2013-09-01

    Full Text Available Respiratory virus infections, such as influenza, typically induce a robust type I (pro-inflammatory cytokine immune response, however, the production of type 2 cytokines has been observed. Type 2 cytokine production during respiratory virus infection is linked to asthma exacerbation; however, type 2 cytokines may also be tissue protective. Interleukin (IL-5 is a prototypical type 2 cytokine that is essential for eosinophil maturation and egress out of the bone marrow. However, little is known about the cellular source and underlying cellular and molecular basis for the regulation of IL-5 production during respiratory virus infection. Using a mouse model of influenza virus infection, we found a robust transient release of IL-5 into infected airways along with a significant and progressive accumulation of eosinophils into the lungs, particularly during the recovery phase of infection, i.e. following virus clearance. The cellular source of the IL-5 was group 2 innate lymphoid cells (ILC2 infiltrating the infected lungs. Interestingly, the progressive accumulation of eosinophils following virus clearance is reflected in the rapid expansion of c-kit⁺ IL-5 producing ILC2. We further demonstrate that the enhanced capacity for IL-5 production by ILC2 during recovery is concomitant with the enhanced expression of the IL-33 receptor subunit, ST2, by ILC2. Lastly, we show that NKT cells, as well as alveolar macrophages (AM, are endogenous sources of IL-33 that enhance IL-5 production from ILC2. Collectively, these results reveal that c-kit⁺ ILC2 interaction with IL-33 producing NKT and AM leads to abundant production of IL-5 by ILC2 and accounts for the accumulation of eosinophils observed during the recovery phase of influenza infection.

  19. Sum rule limitations of kinetic particle-production models

    International Nuclear Information System (INIS)

    Knoll, J.; CEA Centre d'Etudes Nucleaires de Grenoble, 38; Guet, C.

    1988-04-01

    Photoproduction and absorption sum rules generalized to systems at finite temperature provide a stringent check on the validity of kinetic models for the production of hard photons in intermediate energy nuclear collisions. We inspect such models for the case of nuclear matter at finite temperature employed in a kinetic regime which copes those encountered in energetic nuclear collisions, and find photon production rates which significantly exceed the limits imposed by the sum rule even under favourable concession. This suggests that coherence effects are quite important and the production of photons cannot be considered as an incoherent addition of individual NNγ production processes. The deficiencies of present kinetic models may also apply for the production of probes such as the pion which do not couple perturbatively to the nuclear currents. (orig.)

  20. A non-linear model of economic production processes

    Science.gov (United States)

    Ponzi, A.; Yasutomi, A.; Kaneko, K.

    2003-06-01

    We present a new two phase model of economic production processes which is a non-linear dynamical version of von Neumann's neoclassical model of production, including a market price-setting phase as well as a production phase. The rate of an economic production process is observed, for the first time, to depend on the minimum of its input supplies. This creates highly non-linear supply and demand dynamics. By numerical simulation, production networks are shown to become unstable when the ratio of different products to total processes increases. This provides some insight into observed stability of competitive capitalist economies in comparison to monopolistic economies. Capitalist economies are also shown to have low unemployment.

  1. Aspect-Oriented Model-Driven Software Product Line Engineering

    Science.gov (United States)

    Groher, Iris; Voelter, Markus

    Software product line engineering aims to reduce development time, effort, cost, and complexity by taking advantage of the commonality within a portfolio of similar products. The effectiveness of a software product line approach directly depends on how well feature variability within the portfolio is implemented and managed throughout the development lifecycle, from early analysis through maintenance and evolution. This article presents an approach that facilitates variability implementation, management, and tracing by integrating model-driven and aspect-oriented software development. Features are separated in models and composed of aspect-oriented composition techniques on model level. Model transformations support the transition from problem to solution space models. Aspect-oriented techniques enable the explicit expression and modularization of variability on model, template, and code level. The presented concepts are illustrated with a case study of a home automation system.

  2. Systems Engineering Metrics: Organizational Complexity and Product Quality Modeling

    Science.gov (United States)

    Mog, Robert A.

    1997-01-01

    Innovative organizational complexity and product quality models applicable to performance metrics for NASA-MSFC's Systems Analysis and Integration Laboratory (SAIL) missions and objectives are presented. An intensive research effort focuses on the synergistic combination of stochastic process modeling, nodal and spatial decomposition techniques, organizational and computational complexity, systems science and metrics, chaos, and proprietary statistical tools for accelerated risk assessment. This is followed by the development of a preliminary model, which is uniquely applicable and robust for quantitative purposes. Exercise of the preliminary model using a generic system hierarchy and the AXAF-I architectural hierarchy is provided. The Kendall test for positive dependence provides an initial verification and validation of the model. Finally, the research and development of the innovation is revisited, prior to peer review. This research and development effort results in near-term, measurable SAIL organizational and product quality methodologies, enhanced organizational risk assessment and evolutionary modeling results, and 91 improved statistical quantification of SAIL productivity interests.

  3. Models for cell survival with low LET radiation

    International Nuclear Information System (INIS)

    Payne, M.G.; Garrett, W.R.

    1975-01-01

    A model for cell survival under low LET irradiation was developed in which the cell is considered to have N 0 -independent sensitive sites, each of which can exist in either an undamaged state (state A) or one of two damaged states. Radiation can change the sensitive sites from the undamaged state to either of two damaged states. The first damaged state (state B) can either be repaired or be promoted on the second damaged state (state C), which is irreparable. The promotion from the first damaged state to the second can occur due to any of the following: (1) further radiation damage, (2) an abortive attempt to repair the site, or (3) the arrival at a part of the cell cycle where the damage is ''fixed.'' Subject to the further assumptions that radiation damage can occur either indirectly (i.e., through radiation products) or due to direct interaction, and that repair of the first damaged state is a one-step process, expressions can be derived for P(N/sub A/, N/sub B/,t) = probability that after time t a cell will have N/sub A/ sites in state A and N/sub B/ in state B. The problem of determining P(N/sub A/, N/sub B/, t) is formulated for arbitrary time dependences of the radiation field and of all rate coefficients. A large family of cell-survival models can be described by interpreting the sensitive sites in different ways and by making different choices of rate coefficients and of the combinations of numbers of sites in different states that will lead to cell death. (U.S.)

  4. CD8+ T Cells Mediate Female-Dominant IL-4 Production and Airway Inflammation in Allergic Asthma.

    Directory of Open Access Journals (Sweden)

    Chihiro Ito

    Full Text Available The prevalence and severity of bronchial asthma are higher in females than in males after puberty. Although antigen-specific CD8+ T cells play an important role in the development of asthma through their suppressive effect on cytokine production, the contribution of CD8+ T cells to sex differences in asthmatic responses remains unclear. In the present study, we investigated the sex-specific effect of CD8+ T cells in the suppression of asthma using an ovalbumin mouse model of asthma. The number of inflammatory cells in bronchoalveolar lavage (BAL fluid, lung type 2 T-helper cytokine levels, and interleukin-4 (IL-4 production by bronchial lymph node cells were significantly higher in female wild-type (WT mice compared with male mice, whereas no such sex differences were observed between male and female cd8α-disrupted mice. The adaptive transfer of male, but not female, CD8+ T cells reduced the number of inflammatory cells in the recovered BAL fluid of male recipient mice, while no such sex difference in the suppressive activity of CD8+ T cells was observed in female recipient mice. Male CD8+ T cells produced higher levels of IFN-γ than female CD8+ T cells did, and this trend was associated with reduced IL-4 production by male, but not female, CD4+ T cells. Interestingly, IFN-γ receptor expression on CD4+ T cells was significantly lower in female mice than in male mice. These results suggest that female-dominant asthmatic responses are orchestrated by the reduced production of IFN-γ by CD8+ T cells and the lower expression of IFN-γ receptor on CD4+ T cells in females compared with males.

  5. The protective cell petrus for the production of californium 252

    International Nuclear Information System (INIS)

    Sontag, R.; Berger, R.

    1967-01-01

    The alpha, beta, gamma, neutron cell which is described in the present paper is devoted to the transplutonium element production and study. It is located at the CEN in Fontenay-aux-Roses (France). The 4 feet ordinary concrete shielding made of stacked blocs allows the manipulation of radioactive sources as high as 1000 curies of 1 MeV gamma rays and with a fast neutrons flux of 10 9 n.cm -2 .s -1 . The airtight alpha containment box is equipped with two transfer systems, one consists of a parallelepiped shaped airtight box located in a turntable, the other uses standard cylindrical containers made of polyethylene. The general equipment and the main setting up are also described. (authors) [fr

  6. Pricing Participating Products under a Generalized Jump-Diffusion Model

    Directory of Open Access Journals (Sweden)

    Tak Kuen Siu

    2008-01-01

    Full Text Available We propose a model for valuing participating life insurance products under a generalized jump-diffusion model with a Markov-switching compensator. It also nests a number of important and popular models in finance, including the classes of jump-diffusion models and Markovian regime-switching models. The Esscher transform is employed to determine an equivalent martingale measure. Simulation experiments are conducted to illustrate the practical implementation of the model and to highlight some features that can be obtained from our model.

  7. Charm production in the dual topological unitarization model

    International Nuclear Information System (INIS)

    Batunin, A.V.

    1986-01-01

    The open and hidden charm hadroproduction has been traced up to the SPS energies in the framework of the dual parton model. The free parameter (the suppression of the charmed sea) comes from the experiments on D-meson hadroproduction. Then the hidden-charm production data are described assuming that the J/ψ-meson production suggests only one cc-bar pair in the string, while the pair ψψ production suggests two cc-bar pairs

  8. Parallel Development of Products and New Business Models

    OpenAIRE

    Lund, Morten; Hansen, Poul H. Kyvsgård

    2014-01-01

    The perception of product development and the practical execution of product development in professional organizations have undergone dramatic changes in recent years. Many of these chances relate to introduction of broader and more cross-disciplinary views that involves new organizational functions and new concepts. These chances can be captured in various generations of practice. This paper will discuss the recent development of 3rd generation product development process models and the emer...

  9. Real Exchange Rate and Productivity in an OLG Model

    OpenAIRE

    Thi Hong Thinh DOAN; Karine GENTE

    2013-01-01

    This article develops an overlapping generations model to show how demography and savings affect the relationship between real exchange rate (RER) and productivity. In high-saving (low-saving) countries and/or low-population-growth-rate countries, a rise in productivity leads to a real depreciation (appreciation) whereas the RER may appreciate or depreciate in highproduction-growth-rate. Using panel data, we conclude that a rise in productivity generally causes a real exchange rate appreciati...

  10. Biometrics in wearable products: Reverse Engineering and numerical modeling

    OpenAIRE

    Rao, Andrea

    2011-01-01

    The Reverse Engineering (RE) techniques and the Finite Element Modelling (FEM) are widely used tools in many scientific fields. They were firstly developed for the mechanics but in the last times became common for other disciplines. In the thesis these techniques are used for the customization of the wearable products. It is possible to observe that the geometry of whatever wearable product is fundamental for the comfort. In particular, starting from the need of wearable product it is possibl...

  11. The Adequate Corpus Luteum: miR-96 Promotes Luteal Cell Survival and Progesterone Production.

    Science.gov (United States)

    Mohammed, Bushra T; Sontakke, Sadanand D; Ioannidis, Jason; Duncan, W Colin; Donadeu, F Xavier

    2017-07-01

    Inadequate progesterone production from the corpus luteum is associated with pregnancy loss. Data available in model species suggest important roles of microRNAs (miRNAs) in luteal development and maintenance. To comprehensively investigate the involvement of miRNAs during the ovarian follicle-luteal transition. The effects of specific miRNAs on survival and steroid production by human luteinized granulosa cells (hLGCs) were tested using specific miRNA inhibitors. Candidate miRNAs were identified through microarray analyses of follicular and luteal tissues in a bovine model. An academic institution in the United Kingdom associated with a teaching hospital. hLGCs were obtained by standard transvaginal follicular-fluid aspiration from 35 women undergoing assisted conception. Inhibition of candidate miRNAs in vitro. Levels of miRNAs, mRNAs, FOXO1 protein, apoptosis, and steroids were measured in tissues and/or cultured cells. Two specific miRNA clusters, miR-183-96-182 and miR-212-132, were dramatically increased in luteal relative to follicular tissues. miR-96 and miR-132 were the most upregulated miRNAs within each cluster. Database analyses identified FOXO1 as a putative target of both these miRNAs. In cultured hLGCs, inhibition of miR-96 increased apoptosis and FOXO1 protein levels, and decreased progesterone production. These effects were prevented by small interfering RNA-mediated downregulation of FOXO1. In bovine luteal cells, miR-96 inhibition also led to increases in apoptosis and FOXO1 protein levels. miR-96 targets FOXO1 to regulate luteal development through effects on cell survival and steroid production. The miR-183-96-182 cluster could provide a novel target for the manipulation of luteal function. Copyright © 2017 Endocrine Society

  12. Conceptual Development af a 3D Product Configuration Model

    DEFF Research Database (Denmark)

    Skauge, Jørn

    2006-01-01

    in the development of IT-systems that support the procedures in companies and in the building industry. In other words, it is a knowledge-based system that helps companies in their daily work. The aim of the project has been to develop and examine conceptual ideas about 3D modelling configurator used in the company......’s production of steel fire sliding doors. The development of the 3D digital model is based on practical rather than theoretical research. The result of the research is a prototype digital 3D model to be presented live.......Paper. This project deals with 3D product configuration of a digital building element which has been developed as a prototype in cooperation between a product manufacturer and a research institution in Denmark. The project falls within the concept of product modelling which is more and more used...

  13. Official Reports: Inventions, useful models, industrial samples, product certificates

    International Nuclear Information System (INIS)

    1994-01-01

    This serial collection presents brief information on patents, useful models, industrial samples, product certificates and trade marks registered in Uzbekistan. They comprise different branches of human activities including peaceful uses of atomic energy. (A.A.D.)

  14. Official Reports: Inventions, useful models, industrial samples, product certificates

    International Nuclear Information System (INIS)

    1996-01-01

    This serial collection presents brief information on patents, useful models, industrial samples, product certificates and trade marks registered in Uzbekistan. They comprise different branches of human activities including peaceful uses of atomic energy. (A.A.D.)

  15. Official Reports: Inventions, useful models, industrial samples, product certificates

    International Nuclear Information System (INIS)

    1995-01-01

    This serial collection presents brief information on patents, useful models, industrial samples, product certificates and trade marks registered in Uzbekistan. They comprise different branches of human activities including peaceful uses of atomic energy. (A.A.D.)

  16. Selection of productivity improvement techniques via mathematical modeling

    Directory of Open Access Journals (Sweden)

    Mahassan M. Khater

    2011-07-01

    Full Text Available This paper presents a new mathematical model to select an optimal combination of productivity improvement techniques. The proposed model of this paper considers four-stage cycle productivity and the productivity is assumed to be a linear function of fifty four improvement techniques. The proposed model of this paper is implemented for a real-world case study of manufacturing plant. The resulted problem is formulated as a mixed integer programming which can be solved for optimality using traditional methods. The preliminary results of the implementation of the proposed model of this paper indicate that the productivity can be improved through a change on equipments and it can be easily applied for both manufacturing and service industries.

  17. Development of an inpatient operational pharmacy productivity model.

    Science.gov (United States)

    Naseman, Ryan W; Lopez, Ben R; Forrey, Ryan A; Weber, Robert J; Kipp, Kris M

    2015-02-01

    An innovative model for measuring the operational productivity of medication order management in inpatient settings is described. Order verification within a computerized prescriber order-entry system was chosen as the pharmacy workload driver. To account for inherent variability in the tasks involved in processing different types of orders, pharmaceutical products were grouped by class, and each class was assigned a time standard, or "medication complexity weight" reflecting the intensity of pharmacist and technician activities (verification of drug indication, verification of appropriate dosing, adverse-event prevention and monitoring, medication preparation, product checking, product delivery, returns processing, nurse/provider education, and problem-order resolution). The resulting "weighted verifications" (WV) model allows productivity monitoring by job function (pharmacist versus technician) to guide hiring and staffing decisions. A 9-month historical sample of verified medication orders was analyzed using the WV model, and the calculations were compared with values derived from two established models—one based on the Case Mix Index (CMI) and the other based on the proprietary Pharmacy Intensity Score (PIS). Evaluation of Pearson correlation coefficients indicated that values calculated using the WV model were highly correlated with those derived from the CMI-and PIS-based models (r = 0.845 and 0.886, respectively). Relative to the comparator models, the WV model offered the advantage of less period-to-period variability. The WV model yielded productivity data that correlated closely with values calculated using two validated workload management models. The model may be used as an alternative measure of pharmacy operational productivity. Copyright © 2015 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

  18. Advanced methods of solid oxide fuel cell modeling

    CERN Document Server

    Milewski, Jaroslaw; Santarelli, Massimo; Leone, Pierluigi

    2011-01-01

    Fuel cells are widely regarded as the future of the power and transportation industries. Intensive research in this area now requires new methods of fuel cell operation modeling and cell design. Typical mathematical models are based on the physical process description of fuel cells and require a detailed knowledge of the microscopic properties that govern both chemical and electrochemical reactions. ""Advanced Methods of Solid Oxide Fuel Cell Modeling"" proposes the alternative methodology of generalized artificial neural networks (ANN) solid oxide fuel cell (SOFC) modeling. ""Advanced Methods

  19. The Adaptor Protein SAP Regulates Type II NKT Cell Development, Cytokine Production and Cytotoxicity Against Lymphoma1

    Science.gov (United States)

    Weng, Xiufang; Liao, Chia-Min; Bagchi, Sreya; Cardell, Susanna L.; Stein, Paul L.; Wang, Chyung-Ru

    2014-01-01

    CD1d-restricted NKT cells represent a unique lineage of immunoregulatory T cells that are divided into two groups, type I and type II, based on their TCR usage. Because there are no specific tools to identify type II NKT cells, little is known about their developmental requirements and functional regulation. In our previous study, we showed that signaling lymphocytic activation molecule-associated protein (SAP) is essential for the development of type II NKT cells. Here, using a type II NKT cell TCR transgenic mouse model (24αβTg), we demonstrated that CD1d-expressing hematopoietic cells but not thymic epithelial cells meditate efficient selection of type II NKT cells. Further, we showed that SAP regulates type II NKT cell development by controlling Egr2 and PLZF expression. SAP-deficient 24αβ transgenic T cells (24αβ T cells) exhibited an immature phenotype with reduced Th2 cytokine-producing capacity and diminished cytotoxicity to CD1d-expressing lymphoma cells. The impaired IL-4 production by SAP-deficient 24αβ T cells was associated with reduced IRF4 and GATA-3 induction following TCR stimulation. Collectively, these data suggest that SAP is critical for regulating type II NKT cell responses. Aberrant responses of these T cells may contribute to the immune dysregulation observed in X-linked lymphoproliferative disease caused by mutations in SAP. PMID:25236978

  20. A review of planning models for maintenance and production.

    NARCIS (Netherlands)

    G. Budai-Balke (Gabriella); R. Dekker (Rommert); R.P. Nicolai (Robin)

    2006-01-01

    textabstractIn this article we give an overview of the relation between planning of maintenance and production. On the one hand we consider production planning and scheduling models in which failures and maintenance aspects are taken into account. Next we discuss the planning of maintenance

  1. Productive Government Expenditure in Monetary Business Cycle Models

    NARCIS (Netherlands)

    Linnemann, L.; Schabert, A.

    2006-01-01

    This paper assesses the transmission of fiscal policy shocks in a New Keynesian framework where government expenditures contribute to aggregate production. It is shown that even if the impact of government expenditures on production is small, this assumption helps to reconcile the models'

  2. Production compilation : A simple mechanism to model complex skill acquisition

    NARCIS (Netherlands)

    Taatgen, N.A.; Lee, F.J.

    2003-01-01

    In this article we describe production compilation, a mechanism for modeling skill acquisition. Production compilation has been developed within the ACT-Rational (ACT-R; J. R. Anderson, D. Bothell, M. D. Byrne, & C. Lebiere, 2002) cognitive architecture and consists of combining and specializing

  3. Cumulative particle production in the quark recombination model

    International Nuclear Information System (INIS)

    Gavrilov, V.B.; Leksin, G.A.

    1987-01-01

    Production of cumulative particles in hadron-nuclear inteactions at high energies is considered within the framework of recombination quark model. Predictions for inclusive cross sections of production of cumulative particles and different resonances containing quarks in s state are made

  4. Design models in the development of mechatronic products

    DEFF Research Database (Denmark)

    Habib, Tufail; Brunø, Thomas Ditlev; Nielsen, Kjeld

    2012-01-01

    In view of widespread application of mechatronic systems and the competition to offer customized products at high quality and low cost, there has been considerable attention to introduce new methods and models in this regard. This paper explores design process of mechatronic product development w...

  5. Organizational Learning and Product Design Management: Towards a Theoretical Model.

    Science.gov (United States)

    Chiva-Gomez, Ricardo; Camison-Zornoza, Cesar; Lapiedra-Alcami, Rafael

    2003-01-01

    Case studies of four Spanish ceramics companies were used to construct a theoretical model of 14 factors essential to organizational learning. One set of factors is related to the conceptual-analytical phase of the product design process and the other to the creative-technical phase. All factors contributed to efficient product design management…

  6. Property Modelling and Databases in Product-Process Design

    DEFF Research Database (Denmark)

    Gani, Rafiqul; Sansonetti, Sascha

    of the PC-SAFT is used. The developed database and property prediction models have been combined into a properties-software that allows different product-process design related applications. The presentation will also briefly highlight applications of the software for virtual product-process design...

  7. MODEL2TALK : An Intervention to Promote Productive Classroom Talk

    NARCIS (Netherlands)

    van der Veen, Chiel; van der Wilt, Femke; van Kruistum, Claudia; van Oers, Bert; Michaels, Sarah

    2017-01-01

    This article describes the MODEL2TALK intervention, which aims to promote young children's oral communicative competence through productive classroom talk. Productive classroom talk provides children in early childhood education with many opportunities to talk and think together. Results from a

  8. Product Portfolio Management Best Practices For New Product Development: A Review Of Models

    Directory of Open Access Journals (Sweden)

    Doorasamy Mishelle

    2017-02-01

    Full Text Available The survival of any industrial organization depends on whether producing goods or services hinge on how innovative they have become in managing their product portfolio to craft new products that changes with the ever-changing tastes and needs of their customers. This study delves in to the models and theories that drive product portfolio management practices in a way that they support the successes of new product development. Our review is based on selected studies at the frontier of product management, summarized, and compared based on authors experiences, subsisting models, and theories with the results purely based on qualitative rather than quantitative approaches. The essence is to explore possible new theory or model in this field of research.

  9. Utilisation of coal for energy production in fuel cells

    Directory of Open Access Journals (Sweden)

    Dudek Magdalena

    2016-01-01

    Full Text Available In this paper a brief characterization of fuel cell technology and its possible application in sustainable energy development was described. Special attention was paid to direct carbon fuel cell technology. The direct carbon fuel cell is an electrochemical device which directly converts the chemical energy of carbonaceous based fuel into electricity without ‘flame burning’. The electrical efficiency of a DCFC is indeed very high (in practice exceeding 80%, and the product of conversion consists of almost pure CO2, eliminating the most expensive step of sequestration: the separation of carbon from flue gases. In this paper the process of electrochemical oxidation of carbon particles on the surface of oxide electrolytes at 8% mol Y2O3 in ZrO2 (8YSZ as well as cermet anode Ni-8YSZ was analysed. The graphite, carbon black powders were considered as reference solid fuels for coal samples. It was found that the main factors contributing to the electrochemical reactivity of carbon particles is not only the high carbon content in samples but also structural disorder. It was found that structurally disordered carbon-based materials are the most promising solid fuels for direct carbon solid oxide fuel cells. Special impact was placed on the consideration of coal as possible solid fuels for DC-SOFC. Statistical and economic analyses show that in the coming decades, in developing countries such as China, India, and some EU countries, coal-fuelled power plants will maintain their strong position in the power sector due to their reliability and low costs as well as the large reserves of coal and lignite in the world. Coal is mined in politically stable areas, which guarantees its easy and safe purchase and transport. The impact of the physiochemical properties of raw and purified coal on the performance of the DC-SOFC was studied. An analysis of the stability of electrical parameters was performed for a DC-SOFC operating under a load over an extended

  10. Mathematical modeling of the lithium, thionyl chloride static cell. I. Neutral electrolyte. II - Acid electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Tsaur, K.C.; Pollard, R.

    1984-05-01

    Mathematical models are presented for a Li-LiAlCl4/SOCl2-C static cell with neutral electrolyte and a Li/SOCl2-C static cell with acid electrolyte. The model for the Li-LiAlCl4/SOCl2-C cell with neutral solution predicts that high internal resistance can develop in the positive electrode as a result of low local porosities which are, in turn, caused by large-volume, solid reaction products. Consequently, the maximum usable cell capacity is dictated by the nonuniformity of the reaction distribution at the front of the positive electrode. In many respects, a cell with acid electrolyte can be regarded as a combination of an equivalent neutral electrolyte system and an acid reservoir. The model for the Li/SOCl2 cell suggests that the cell life depends primarily on the quantity of acid added to the electrolyte. 58 references.

  11. Mathematical modeling of the lithium, thionyl chloride static cell. I - Neutral electrolyte. II - Acid electrolyte

    Science.gov (United States)

    Tsaur, K.-C.; Pollard, R.

    1984-05-01

    Mathematical models are presented for a Li-LiAlCl4/SOCl2-C static cell with neutral electrolyte and a Li/SOCl2-C static cell with acid electrolyte. The model for the Li-LiAlCl4/SOCl2-C cell with neutral solution predicts that high internal resistance can develop in the positive electrode as a result of low local porosities which are, in turn, caused by large-volume, solid reaction products. Consequently, the maximum usable cell capacity is dictated by the nonuniformity of the reaction distribution at the front of the positive electrode. In many respects, a cell with acid electrolyte can be regarded as a combination of an equivalent neutral electrolyte system and an acid reservoir. The model for the Li/SOCl2 cell suggests that the cell life depends primarily on the quantity of acid added to the electrolyte.

  12. Enzyme production in immobilized Trichoderma reesei cells with hydrophobic polymers prepared by radiation polymerization method

    International Nuclear Information System (INIS)

    Luzhao Xin; Kumakura, Minoru; Kaetsu, Isao

    1993-01-01

    Trichoderma reesei cells were immobilized on paper covered with hydrophobic monomer, trimethylpropane triacrylate by radiation polymerization. The effect of immobilization condition on enzyme productivity was studied by measuring filter paper and cellobiose activity. The cells were adhered and grew on the surface of the carrier with the polymer giving high enzyme productivity in the immobilized cells in comparison with the free cells. Optimum concentration and volume of the coating monomer for the preparation of the immobilized cells were obtained. (author)

  13. Computational cell model based on autonomous cell movement regulated by cell-cell signalling successfully recapitulates the "inside and outside" pattern of cell sorting

    Directory of Open Access Journals (Sweden)

    Ajioka Itsuki

    2007-09-01

    Full Text Available Abstract Background Development of multicellular organisms proceeds from a single fertilized egg as the combined effect of countless numbers of cellular interactions among highly dynamic cells. Since at least a reminiscent pattern of morphogenesis can be recapitulated in a reproducible manner in reaggregation cultures of dissociated embryonic cells, which is known as cell sorting, the cells themselves must possess some autonomous cell behaviors that assure specific and reproducible self-organization. Understanding of this self-organized dynamics of heterogeneous cell population seems to require some novel approaches so that the approaches bridge a gap between molecular events and morphogenesis in developmental and cell biology. A conceptual cell model in a computer may answer that purpose. We constructed a dynamical cell model based on autonomous cell behaviors, including cell shape, growth, division, adhesion, transformation, and motility as well as cell-cell signaling. The model gives some insights about what cellular behaviors make an appropriate global pattern of the cell population. Results We applied the model to "inside and outside" pattern of cell-sorting, in which two different embryonic cell types within a randomly mixed aggregate are sorted so that one cell type tends to gather in the central region of the aggregate and the other cell type surrounds the first cell type. Our model can modify the above cell behaviors by varying parameters related to them. We explored various parameter sets with which the "inside and outside" pattern could be achieved. The simulation results suggested that direction of cell movement responding to its neighborhood and the cell's mobility are important for this specific rearrangement. Conclusion We constructed an in silico cell model that mimics autonomous cell behaviors and applied it to cell sorting, which is a simple and appropriate phenomenon exhibiting self-organization of cell population. The model

  14. Immunoglobulin production induced in vitro by glucocorticoid hormones: T cell-dependent stimulation of immunoglobulin production without B cell proliferation in cultures of human peripheral blood lymphocytes

    International Nuclear Information System (INIS)

    Grayson, J.; Dooley, N.J.; Koski, I.R.; Blaese, R.M.

    1981-01-01

    The direct effects of steroid hormones on the production of immunoglobulins and DNA synthesis by human T and B lymphocytes was evaluated in cultures of peripheral blood mononuclear cells. As detected by a reverse hemolytic plaque assay, the addition of 0.1 mM to 10 nM hydrocortisone to lymphocytes in culture in the absence of other stimulants or mitogens, resulted in the dramatic induction of immunoglobulin production with responses comparable to those seen in similar cultures stimulated with pokeweed mitogen. Steroid-stimulated immunoglobulin production was first seen after 48 h and peaked at 8-10 d of culture. The production of IgG, IgA, and IgM was induced following incubation with steroid. Glucocorticoids, but not estrogens or androgens, were capable of mediating this effect, and only compounds with affinity for the glucocorticoid receptor were active. The induction of immunoglobulin production was dependent on both T cells and monocytes; cultures depleted of either cell type did not produce immunoglobulin when stimulated with glucocorticoid hormones. Proliferation of B cells or T cells could not be detected by [/sup 3/H]thymidine incorporation or total cell recovery from steroid-stimulated cultures, even though such cultures demonstrated marked increases in immunoglobulin production. The mechanism responsible for this functional maturation of B cells to become high rate immunoglobulin producing cells is as yet undefined, although it appears to involve more than merely steroid mediated inactivation of suppressor T cells

  15. Trade and Variety in a Model of Endogenous Product Differentiation

    OpenAIRE

    Oliver Lorz; Matthias Wrede

    2009-01-01

    This paper sets up a model of endogenous product differentiation to analyze the variety effects of international trade. In our model multi-product firms decide not only about the number of varieties they supply but also about the degree of horizontal differentiation between these varieties. Firms can raise the degree of differentiation by investing variety-specific fixed costs. In this setting, we analyze how trade integration, i.e. an increase in market size, influences the number of firms i...

  16. Simulation modeling for quality and productivity in steel cord manufacturing

    OpenAIRE

    Türkseven, Can Hulusi; Turkseven, Can Hulusi; Ertek, Gürdal; Ertek, Gurdal

    2003-01-01

    We describe the application of simulation modeling to estimate and improve quality and productivity performance of a steel cord manufacturing system. We describe the typical steel cord manufacturing plant, emphasize its distinguishing characteristics, identify various production settings and discuss applicability of simulation as a management decision support tool. Besides presenting the general structure of the developed simulation model, we focus on wire fractures, which can be an important...

  17. Product Modelling for Building Design: Annotated Bibliography (2nd Edition)

    DEFF Research Database (Denmark)

    Galle, Per

    1999-01-01

    This bibliography concerns research publications from 1976 to 1994-5, on product modelling in computer aided architectural design and computer aided engineering design of buildings and their surroundings. For each item of literature, full bibliographic information is given whenever available...... of literature is offered on machine interpretation of drawings, which may be relevant in the context of information exchange among different product models. Although the bibliography is fairly comprehensive as far as it goes, no completeness of coverage is claimed....

  18. The influence of naphthaleneacetic acid (NAA) and coumarin on flavonoid production by fungus Phellinus sp.: modeling of production kinetic profiles.

    Science.gov (United States)

    Ma, Xiao-Kui; Li, Le; Peterson, Eric Charles; Ruan, Tingting; Duan, Xiaoyi

    2015-11-01

    For the purpose of improving the fungal production of flavonoids, the influence of naphthaleneacetic acid (NAA) and coumarin on flavonoid production by fungus Phellinus sp. P0988 was investigated by developing the corresponding kinetics of flavonoid production in a 7-L bioreactor. Phellinus sp. was confirmed to form flavonoids in pellets and broth when cultivated in basic medium, and the optimum concentration of NAA and coumarin in medium for flavonoid production were determined to be 0.03 and 0.02 g/L, respectively. The developed unstructured mathematical models were in good agreement with the experimental results with respect to flavonoid production kinetic profiles with NAA and coumarin supplementation at optimum levels and revealed significant accuracy in terms of statistical consistency and robustness. Analysis of these kinetic processes indicated that NAA and coumarin supplementations imposed a stronger positive influence on flavonoid production and substrate consumption compared to their effects on cell growth. The separate addition of NAA and coumarin resulted in enhancements in final product accumulation and productivity, achieving final flavonoid concentrations of 3.60 and 2.75 g/L, respectively, and glucose consumption showed a significant decrease compared to the non-supplemented control as well. Also, the separate presence of NAA and coumarin respectively decreased maintenance coefficients (M s) from 2.48 in the control to 1.39 and 0.22, representing decreases of 43.9 and 91.1 %, respectively. The current study is the first known application of mathematical kinetic models to explore the influence of medium components adding on flavonoid production by fungi.

  19. Organic and Inorganic Nitrogen Impact Chlorella variabilis Productivity and Host Quality for Viral Production and Cell Lysis.

    Science.gov (United States)

    Cheng, Yu-Shen; Labavitch, John; VanderGheynst, Jean S

    2015-05-01

    Microalgae have been proposed as a potential feedstock for biofuel production; however, cell disruption is usually required for collection and utilization of cytoplasmic polysaccharides and lipids. Virus infection might be one approach to disrupt the cell wall. The concentration of yeast extract and presence of KNO3 in algae cultivation media were investigated to observe their effects on Chlorella variabilis NC64A physiology and composition and the subsequent effect on production of Chlorella virus and disruption of infected cells. Cytoplasmic starch accumulation increased from 5% to approximately 35% of the total dry weight when yeast extract decreased from 1 to 0.25 g L(-1). When cells were cultured with the lowest nitrogen levels, the total polysaccharide accounted for more than 50% of the cell wall, which was 1.7 times higher than the content in cells cultured with the highest nitrogen levels. The C/N ratio of the algal biomass decreased by a factor of approximately 2 when yeast extract increased from 0.25 to 1 g L(-1). After virus infection, cells with a low C/N ratio produced a 7.6 times higher burst size than cells with a high C/N ratio, suggesting that the nitrogen content in C. variabilis has a large influence on viral production and cell lysis. The results have implications on management of nitrogen for both the synthesis of products from algae and product recovery via viral lysis.

  20. Interactions of Model Cell Membranes with Nanoparticles

    Science.gov (United States)

    D'Angelo, S. M.; Camesano, T. A.; Nagarajan, R.

    2011-12-01

    The same properties that give nanoparticles their enhanced function, such as high surface area, small size, and better conductivity, can also alter the cytotoxicity of nanomaterials. Ultimately, many of these nanomaterials will be released into the environment, and can cause cytotoxic effects to environmental bacteria, aquatic organisms, and humans. Previous results from our laboratory suggest that nanoparticles can have a detrimental effect on cells, depending on nanoparticle size. It is our goal to characterize the properties of nanomaterials that can result in membrane destabilization. We tested the effects of nanoparticle size and chemical functionalization on nanoparticle-membrane interactions. Gold nanoparticles at 2, 5,10, and 80 nm were investigated, with a concentration of 1.1x1010 particles/mL. Model cell membranes were constructed of of L-α-phosphatidylcholine (egg PC), which has negatively charged lipid headgroups. A quartz crystal microbalance with dissipation (QCM-D) was used to measure frequency changes at different overtones, which were related to mass changes corresponding to nanoparticle interaction with the model membrane. In QCM-D, a lipid bilayer is constructed on a silicon dioxide crystal. The crystals, oscillate at different harmonic frequencies depending upon changes in mass or energy dissipation. When mass is added to the crystal surface, such as through addition of a lipid vesicle solution, the frequency change decreases. By monitoring the frequency and dissipation, we could verify that a supported lipid bilayer (SLB) formed on the silica surface. After formation of the SLB, the nanoparticles can be added to the system, and the changes in frequency and dissipation are monitored in order to build a mechanistic understanding of nanoparticle-cell membrane interactions. For all of the smaller nanoparticles (2, 5, and 10 nm), nanoparticle addition caused a loss of mass from the lipid bilayer, which appears to be due to the formation of holes