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Sample records for repeated batch cultures

  1. Simulation of Feedforward-Feedback Control of Dissolved Oxygen of Microbial Repeated Fed-batch Culture

    Directory of Open Access Journals (Sweden)

    Ling Gao

    2016-09-01

    Full Text Available Fed-batch culture is often used in industry, and dissolved oxygen (DO concentration control is important in fermentation process control. DO control is often applied by using feedback (FB control strategy. But, feedforward-feedback (FF-FB control has the advantage in dealing with the time-varying characteristics resulted from the cell growth during the fermentation process. Mathematical modeling and computer simulation is a useful tool in analysis of the control system.  In this research, the FF-FB DO control and FB substrate control of repeated fed-batch culture process is modeled and simulated. The results showed the feasibility of the control strategy. These results are useful for control system development and process analyses and optimization.

  2. Biosynthesis of highly enriched 13C-lycopene for human metabolic studies using repeated batch tomato cell culturing with 13C-glucose

    Science.gov (United States)

    Moran, Nancy E.; Rogers, Randy B.; Lu, Chi-Hua; Conlon, Lauren E.; Lila, Mary Ann; Clinton, Steven K.; Erdman, John W.

    2013-01-01

    While putative disease-preventing lycopene metabolites are found in both tomato (Solanum lycopersicum) products and in their consumers, mammalian lycopene metabolism is poorly understood. Advances in tomato cell culturing techniques offer an economical tool for generation of highly-enriched 13C-lycopene for human bioavailability and metabolism studies. To enhance the 13C-enrichment and yields of labeled lycopene from the hp-1 tomato cell line, cultures were first grown in 13C-glucose media for three serial batches and produced increasing proportions of uniformly labeled lycopene (14.3 +/− 1.2 %, 39.6 +/− 0.5 %, and 48.9 +/− 1.5% with consistent yields (from 5.8 to 9 mg/L). An optimized 9-day-long 13C-loading and 18-day-long labeling strategy developed based on glucose utilization and lycopene yields, yielded 13C-lycopene with 93% 13C isotopic purity, and 55% of isotopomers were uniformly labeled. Furthermore, an optimized acetone and hexane extraction led to a four-fold increase in lycopene recovery from cultures compared to a standard extraction. PMID:23561155

  3. Improving cellulase productivity of Penicillium oxalicum RE-10 by repeated fed-batch fermentation strategy.

    Science.gov (United States)

    Han, Xiaolong; Song, Wenxia; Liu, Guodong; Li, Zhonghai; Yang, Piao; Qu, Yinbo

    2017-03-01

    Medium optimization and repeated fed-batch fermentation were performed to improve the cellulase productivity by P. oxalicum RE-10 in submerged fermentation. First, Plackett-Burman design (PBD) and central composite design (CCD) were used to optimize the medium for cellulase production. PBD demonstrated wheat bran and NaNO 3 had significant influences on cellulase production. The CCD results showed the maximum filter paper activity (FPA) production of 8.61U/mL could be achieved in Erlenmeyer flasks. The maximal FPA reached 12.69U/mL by submerged batch fermentation in a 7.5-L stirred tank, 1.76-fold higher than that on the original medium. Then, the repeated fed-batch fermentation strategy was performed successfully for increasing the cellulase productivity from 105.75U/L/h in batch fermentation to 158.38U/L/h. The cellulase activity and the glucan conversion of delignined corn cob residue hydrolysis had no significant difference between the enzymes sampled from different cycles of the repeated fed-batch fermentation and that from batch culture. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Repeated batch and continuous degradation of chlorpyrifos by Pseudomonas putida.

    Science.gov (United States)

    Pradeep, Vijayalakshmi; Subbaiah, Usha Malavalli

    2015-01-01

    The present study was undertaken with the objective of studying repeated batch and continuous degradation of chlorpyrifos (O,O-diethyl O-3,5,6-trichloropyridin-2-yl phosphorothioate) using Ca-alginate immobilized cells of Pseudomonas putida isolated from an agricultural soil, and to study the genes and enzymes involved in degradation. The study was carried out to reduce the toxicity of chlorpyrifos by degrading it to less toxic metabolites. Long-term stability of pesticide degradation was studied during repeated batch degradation of chlorpyrifos, which was carried out over a period of 50 days. Immobilized cells were able to show 65% degradation of chlorpyrifos at the end of the 50th cycle with a cell leakage of 112 × 10(3) cfu mL(-1). During continuous treatment, 100% degradation was observed at 100 mL h(-1) flow rate with 2% chlorpyrifos, and with 10% concentration of chlorpyrifos 98% and 80% degradation was recorded at 20 mL h(-1) and 100 mL h(-1) flow rate respectively. The products of degradation detected by liquid chromatography-mass spectrometry analysis were 3,5,6-trichloro-2-pyridinol and chlorpyrifos oxon. Plasmid curing experiments with ethidium bromide indicated that genes responsible for the degradation of chlorpyrifos are present on the chromosome and not on the plasmid. The results of Polymerase chain reaction indicate that a ~890-bp product expected for mpd gene was present in Ps. putida. Enzymatic degradation studies indicated that the enzymes involved in the degradation of chlorpyrifos are membrane-bound. The study indicates that immobilized cells of Ps. putida have the potential to be used in bioremediation of water contaminated with chlorpyrifos.

  5. Production of nattokinase by batch and fed-batch culture of Bacillus subtilis.

    Science.gov (United States)

    Cho, Young-Han; Song, Jae Yong; Kim, Kyung Mi; Kim, Mi Kyoung; Lee, In Young; Kim, Sang Bum; Kim, Hyeon Shup; Han, Nam Soo; Lee, Bong Hee; Kim, Beom Soo

    2010-09-30

    Nattokinase was produced by batch and fed-batch culture of Bacillus subtilis in flask and fermentor. Effect of supplementing complex media (peptone, yeast extract, or tryptone) was investigated on the production of nattokinase. In flask culture, the highest cell growth and nattokinase activity were obtained with 50 g/L of peptone supplementation. In this condition, nattokinase activity was 630 unit/ml at 12 h. In batch culture of B. subtilis in fermentor, the highest nattokinase activity of 3400 unit/ml was obtained at 10h with 50 g/L of peptone supplementation. From the batch kinetics data, it was shown that nattokinase production was growth-associated and culture should be harvested before stationary phase for maximum nattokinase production. In fed-batch culture of B. subtilis using pH-stat feeding strategy, cell growth (optical density monitored at 600 nm) increased to ca. 100 at 22 h, which was 2.5 times higher than that in batch culture. The highest nattokinase activity was 7100 unit/ml at 19 h, which was also 2.1 times higher than that in batch culture. Copyright 2010 Elsevier B.V. All rights reserved.

  6. Modeling of oxide reduction in repeated-batch pyroprocessing

    International Nuclear Information System (INIS)

    Lee, Hyo Jik; Im, Hun Suk; Park, Geun Il

    2016-01-01

    Highlights: • Pyroprocessing is a complicated batch-type operation. • Discrete event system modeling was used to create an integrated operation model. • Simulation showed that could be accomplished. • The dynamic material flow helps us understand the process operation. • We showed that complex material flow could be simulated in terms of mass balance. - Abstract: Pyroprocessing is a complicated batch-type operation, involving a highly complex material flow logic with a huge number of unit processes. Discrete event system modeling was used to create an integrated operation model for which simulation showed that dynamic material flow could be accomplished to provide considerable insight into the process operation. In the model simulation, the amount of material transported upstream and downstream in the process satisfies a mass balance equation while considering the hold-up incurred by every batch operation. This study also simulated, in detail, an oxide reduction group process embracing electrolytic reduction, cathode processing, and salt purification. Based on the default operation scenario, it showed that complex material flows could be precisely simulated in terms of the mass balance. Specifically, the amount of high-heat elements remaining in the molten salt bath is analyzed to evaluate the operation scenario.

  7. Repeated batch production of ethanol from Jerusalem artichoke tubers using recycled immobilized cells of Kluyveromyces fragilis

    Energy Technology Data Exchange (ETDEWEB)

    Margaritis, A.; Bajpai, P.

    1981-01-01

    Recycled immobilized cells of K. fragilis ATCC 28244 were used for repeated batch production of EtOH from the inulin sugars derived from Jerusalem artichoke tubers. Using 10% initial sugar concentration, a maximum EtOH concentration of 48 g/l was achieved in 7 h when the immobilized cell concentration in the Ca alginate beads was 72 g dry weight immobilized cell/l bioreactor vol.-h. The same Ca alginate beads containing the cells were used repeatedly for 11 batch runs starting with fresh medium at the beginning of each run. The EtOH yield was almost constant at 96% of the theoretical for all 11 batch runs, while the maximum EtOH production rate during the last batch run was 70% of the original EtOH rate obtained in the 1st batch run.

  8. Establishing column batch repeatability according to Quality by Design (QbD) principles using modeling software.

    Science.gov (United States)

    Rácz, Norbert; Kormány, Róbert; Fekete, Jenő; Molnár, Imre

    2015-04-10

    Column technology needs further improvement even today. To get information of batch-to-batch repeatability, intelligent modeling software was applied. Twelve columns from the same production process, but from different batches were compared in this work. In this paper, the retention parameters of these columns with real life sample solutes were studied. The following parameters were selected for measurements: gradient time, temperature and pH. Based on calculated results, batch-to-batch repeatability of BEH columns was evaluated. Two parallel measurements on two columns from the same batch were performed to obtain information about the quality of packing. Calculating the average of individual working points at the highest critical resolution (R(s,crit)) it was found that the robustness, calculated with a newly released robustness module, had a success rate >98% among the predicted 3(6) = 729 experiments for all 12 columns. With the help of retention modeling all substances could be separated independently from the batch and/or packing, using the same conditions, having high robustness of the experiments. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Medium optimization for protopectinase production by batch culture of

    African Journals Online (AJOL)

    Medium optimization for protopectinase production by batch culture of. C Fan, Z Liu, L Yao. Abstract. Optimization of medium compositions for protopectinase production by Aspergillus terreus in submerged culture was carried out. The medium components having significant effect on protopectinase production were reported ...

  10. Batch variation between branchial cell cultures: An analysis of variance

    DEFF Research Database (Denmark)

    Hansen, Heinz Johs. Max; Grosell, M.; Kristensen, L.

    2003-01-01

    We present in detail how a statistical analysis of variance (ANOVA) is used to sort out the effect of an unexpected batch-to-batch variation between cell cultures. Two separate cultures of rainbow trout branchial cells were grown on permeable filtersupports ("inserts"). They were supposed...... and introducing the observed difference between batches as one of the factors in an expanded three-dimensional ANOVA, we were able to overcome an otherwisecrucial lack of sufficiently reproducible duplicate values. We could thereby show that the effect of changing the apical medium was much more marked when...... the radioactive lipid precursors were added on the apical, rather than on the basolateral, side. Theinsert cell cultures were obviously polarized. We argue that it is not reasonable to reject troublesome experimental results, when we do not know a priori that something went wrong. The ANOVA is a very useful...

  11. Continuous citric acid production in repeated-fed batch fermentation by Aspergillus niger immobilized on a new porous foam.

    Science.gov (United States)

    Yu, Bin; Zhang, Xin; Sun, Wenjun; Xi, Xun; Zhao, Nan; Huang, Zichun; Ying, Zhuojun; Liu, Li; Liu, Dong; Niu, Huanqing; Wu, Jinglan; Zhuang, Wei; Zhu, Chenjie; Chen, Yong; Ying, Hanjie

    2018-03-24

    The efficiency of current methods for industrial production of citric acid is limited. To achieve continuous citric acid production with enhanced yield and reduced cost, immobilized fermentation was employed in an Aspergillus niger 831 repeated fed-batch fermentation system. We developed a new type of material (PAF201), which was used as a carrier for the novel adsorption immobilization system. Hydrophobicity, pore size and concentration of carriers were researched in A. niger immobilization. The efficiency of the A. niger immobilization process was analyzed by scanning electron microscopy. Then eight-cycle repeated fed-batch cultures for citric acid production were carried out over 600 h, which showed stable production with maximum citric acid concentrations and productivity levels of 162.7 g/L and 2.26 g L -1  h -1 , respectively. Compared with some other literatures about citric acid yield, PAF201 immobilization system is 11.3% higher than previous results. These results indicated that use of the new adsorption immobilization system could greatly improve citric acid productivity in repeated fed-batch fermentation. Moreover, these results could provide a guideline for A.niger or other filamentous fungi immobilization in industry. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. The morphology of Ganoderma lucidum mycelium in a repeated-batch fermentation for exopolysaccharide production

    Directory of Open Access Journals (Sweden)

    Wan Abd Al Qadr Imad Wan-Mohtar

    2016-09-01

    Full Text Available The morphology of Ganoderma lucidum BCCM 31549 mycelium in a repeated-batch fermentation (RBF was studied for exopolysaccharide (EPS production. RBF was optimised for time to replace and volume to replace. G. lucidum mycelium showed the ability to self-immobilise and exhibited high stability for repeated use in RBF with engulfed pellets. Furthermore, the ovoid and starburst-like pellet morphology was disposed to EPS production in the shake flask and bioreactor, respectively. Seven RBF could be carried out in 500 mL flasks, and five repeated batches were performed in a 2 L bioreactor. Under RBF conditions, autolysis of pellet core in the shake flask and shaving off of the outer hairy region in the bioreactor were observed at the later stages of RBF (R4 for the shake flask and R6 for the bioreactor. The proposed strategy showed that the morphology of G. lucidum mycelium can withstand extended fermentation cycles.

  13. Bagasse hydrolyzates from Agave tequilana as substrates for succinic acid production by Actinobacillus succinogenes in batch and repeated batch reactor.

    Science.gov (United States)

    Corona-González, Rosa Isela; Varela-Almanza, Karla María; Arriola-Guevara, Enrique; Martínez-Gómez, Álvaro de Jesús; Pelayo-Ortiz, Carlos; Toriz, Guillermo

    2016-04-01

    The aim of this work was to obtain fermentable sugars by enzymatic or acid hydrolyses of Agave tequilana Weber bagasse in order to produce succinic acid with Actinobacillus succinogenes. Hydrolyses were carried out with mineral acids (sulfuric and hydrochloric acids) or a commercial cellulolytic enzyme, and were optimized statistically by a response surface methodology, having as factors the concentration of acid/enzyme and time of hydrolysis. The concentration of sugars obtained at optimal conditions for each hydrolysis were 21.7, 22.4y 19.8g/L for H2SO4, HCl and the enzymatic preparation respectively. Concerning succinic acid production, the enzymatic hydrolyzates resulted in the highest yield (0.446g/g) and productivity (0.57g/Lh) using A. succinogenes in a batch reactor system. Repeated batch fermentation with immobilized A. succinogenes in agar and with the enzymatic hydrolyzates resulted in a maximum concentration of succinic acid of 33.6g/L from 87.2g/L monosaccharides after 5 cycles in 40h, obtaining a productivity of 1.32g/Lh. Copyright © 2016. Published by Elsevier Ltd.

  14. Fuel ethanol production from sweet sorghum using repeated-batch fermentation.

    Science.gov (United States)

    Chohnan, Shigeru; Nakane, Megumi; Rahman, M Habibur; Nitta, Youji; Yoshiura, Takanori; Ohta, Hiroyuki; Kurusu, Yasurou

    2011-04-01

    Ethanol was efficiently produced from three varieties of sweet sorghum using repeated-batch fermentation without pasteurization or acidification. Saccharomyces cerevisiae cells could be recycled in 16 cycles of the fermentation process with good ethanol yields. This technique would make it possible to use a broader range of sweet sorghum varieties for ethanol production. Copyright © 2010 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  15. A parametric study ot protease production in batch and fed-batch cultures of Bacillus firmus.

    Science.gov (United States)

    Moon, S H; Parulekar, S J

    1991-03-05

    Proteolytic enzymes produced by Bacillus species find a wide variety of applications in brewing, detergent, food, and leather industries. Owing to significant differences normally observed in culture conditions promoting cell growth and those promoting production of metabolites such as enzymes, for increased efficacy of bioreactor operations it is essential to identify these sets of conditions (including medium formulation). This study is focused on formulation of a semidefined medium that substantially enhances synthesis and secretion of an alkaline protease in batch cultures of Bacillus firmus NRS 783, a known superior producer of this enzyme. The series of experiments conducted to identify culture conditions that lead to improved protease production also enables investigation of the regulatory effects of important culture parameters including pH, dissolved oxygen, and concentrations of nitrogen and phosphorous sources and yeast extract in the medium on cell growth, synthesis and secretion of protease, and production of two major nonbiomass products, viz., acetic acid and ethanol. Cell growth and formation of the three nonbiomass products are hampered significantly under nitrogen, phosphorous, or oxygen limitation, with the cells being unable to grow in an oxygen-free environment. Improvement in protease production is achieved with respect to each culture parameter, leading in the process to 80% enhancement in protease activity over that attained using media reported in the literature. Results of a few fed-batch experiments with constant feed rate, conducted to examine possible enhancement in protease production and to further investigate repression of protease synthesis by excess of the principal carbon and nitrogen sources, are also discussed. The detailed investigation of stimulatory and repressory effects of simple and complex nutrients on protease production and metabolism of Bacillus firmus conducted in this study will provide useful guidelines for design

  16. Improving lactic acid productivity from wheat straw hydrolysates by membrane integrated repeated batch fermentation under non-sterilized conditions

    DEFF Research Database (Denmark)

    Zhang, Yuming; Chen, Xiangrong; Qi, Benkun

    2014-01-01

    to eliminate the sequential utilization of mixed sugar and feedback inhibition during batch fermentation, membrane integrated repeated batch fermentation (MIRB) was used to improve LA productivity. With MIRB, a high cell density was obtained and the simultaneous fermentation of glucose, xylose and arabinose...

  17. Repeated batch fermentation of immobilized E. coli expressing Vitreoscilla hemoglobin for long-term use.

    Science.gov (United States)

    Sar, Taner; Seker, Gamze; Erman, Ayse Gokce; Stark, Benjamin C; Yesilcimen Akbas, Meltem

    2017-09-03

    This study describes an efficient and reusable process for ethanol production from medium containing whey powder, using alginate immobilized ethanologenic E. coli strains either expressing (TS3) or not expressing (FBR5) Vitreoscilla hemoglobin. Reuseabilities of the FBR5 and TS3 strains were investigated regarding their ethanol production capacities over the course of 15 successive 96-h batch fermentations. The ethanol production was fairly stable over the entire duration of the experiment, with strain TS3 maintaining a substantial advantage over strain FBR5. Storage of both strains in 2 different solutions for up to 60 d resulted in only a modest loss of ethanol production, with strain TS3 consistently outperforming strain FBR5 by a substantial amount. Strains stored for 15 or 30 d maintained their abilities to produce ethanol without dimunition over the course of 8 successive batch fermentations; again strain TS3 maintained a substantial advantage over strain FBR5 throughout the entire experiment. Thus, immobilization is a useful strategy to maintain the advantage in ethanol productivity afforded by expression of Vitreoscilla hemoglobin over long periods of time and large numbers of repeated batch fermentations, including, as in this case, using media with food processing wastes as the carbon source.

  18. Bio-ethanol Production from Green Onion by Yeast in Repeated Batch.

    Science.gov (United States)

    Robati, Reza

    2013-09-01

    Considered to be the cleanest liquid fuel, bio-ethanol can be a reliable alternative to fossil fuels. It is produced by fermentation of sugar components of plant materials. The common onions are considered to be a favorable source of fermentation products as they have high sugar contents as well as contain various nutrients. This study focused on the effective production of ethanol from Green onion (Allium fistulosum L.) by the yeast "Saccharomyces cerevisiae" in repeated batch. The results showed that the total sugar concentration of onion juice was 68.4 g/l. The maximum rate of productivity, ethanol yield and final bio-ethanol percentage was 7 g/l/h (g ethanol per liter of onion juice per hour), 35 g/l (g ethanol per liter of onion juice) and 90 %, respectively.

  19. Repeated batch cultivation of the hydrocarbon-degrading, micro-algal strain Prototheca zopfii RND16 immobilized in polyurethane foam.

    Science.gov (United States)

    Ueno, Ryohei; Wada, Shun; Urano, Naoto

    2008-01-01

    This study reports on the stability of the cells of a heterotrophic green micro-algal strain Prototheca zopfii RND16 immobilized in polyurethane foam (PUF) cubes during degradation of mixed hydrocarbon substrate, which was composed of n-alkanes and polycyclic aromatic hydrocarbons (PAHs), in 5 successive cycles of repeated batch cultivation at 30 degrees C. Both RND16 cells and mixed hydrocarbon substrate components had been entrapped in PUF cubes through cultivation. PUF-immobilized RND16 degraded n-alkanes almost completely, whereas the strain hardly degraded PAHs in PUFs, rather they accumulated in the matrices. It is noteworthy that this result is strikingly different from that of the free-living cell culture, where RND16 reduced concentrations of both n-alkanes and PAHs. However, PAHs accumulation in the PUFs did not impair the performance of the immobilized alga to utilize n-alkanes. These results suggest that the PUFs harboring RND16 cells could be used repeatedly for selective retrieval of PAHs from oil-polluted waters after preferential biodegradation of n-alkanes by algae.

  20. Lipid production in batch and fed-batch cultures of Rhodosporidium toruloides from 5 and 6 carbon carbohydrates

    Directory of Open Access Journals (Sweden)

    Wiebe Marilyn G

    2012-05-01

    Full Text Available Abstract Background Microbial lipids are a potential source of bio- or renewable diesel and the red yeast Rhodosporidium toruloides is interesting not only because it can accumulate over 50% of its dry biomass as lipid, but also because it utilises both five and six carbon carbohydrates, which are present in plant biomass hydrolysates. Methods R. toruloides was grown in batch and fed-batch cultures in 0.5 L bioreactors at pH 4 in chemically defined, nitrogen restricted (C/N 40 to 100 media containing glucose, xylose, arabinose, or all three carbohydrates as carbon source. Lipid was extracted from the biomass using chloroform-methanol, measured gravimetrically and analysed by GC. Results Lipid production was most efficient with glucose (up to 25 g lipid L−1, 48 to 75% lipid in the biomass, at up to 0.21 g lipid L−1 h−1 as the sole carbon source, but high lipid concentrations were also produced from xylose (36 to 45% lipid in biomass. Lipid production was low (15–19% lipid in biomass with arabinose as sole carbon source and was lower than expected (30% lipid in biomass when glucose, xylose and arabinose were provided simultaneously. The presence of arabinose and/or xylose in the medium increased the proportion of palmitic and linoleic acid and reduced the proportion of oleic acid in the fatty acids, compared to glucose-grown cells. High cell densities were obtained in both batch (37 g L−1, with 49% lipid in the biomass and fed-batch (35 to 47 g L−1, with 50 to 75% lipid in the biomass cultures. The highest proportion of lipid in the biomass was observed in cultures given nitrogen during the batch phase but none with the feed. However, carbohydrate consumption was incomplete when the feed did not contain nitrogen and the highest total lipid and best substrate consumption were observed in cultures which received a constant low nitrogen supply. Conclusions Lipid production in R. toruloides was lower from arabinose and mixed

  1. Study on Molasses Concentration from Sugarcanne Bagasse for Biohydrogen Production using Enriched Granular Activated Carbon (GAC) Immobilised Cells by Repeated Batch Cultivation

    Science.gov (United States)

    Idris, Norfatiha; Aminah Lutpi, Nabilah; Ruhaizul Che Ridzuan, Che Mohd; Shian, Wong Yee; Nuraiti Tengku Izhar, Tengku

    2018-03-01

    Repeated batch cultivation is known as most attractive method in improving hydrogen productivity, due to the facts that this approach could minimize the reuse of the cell and the inoculum preparation. In addition, with the combination of attach growth system during the fermentation processes to produce biohydrogen, the density of cells will be increased and the cell washout could be avoided. Therefore, this study aimed to examine the effectiveness of repeated batch cultivation for enrichment of anaerobic mixed culture onto granular activated carbon (GAC) and investigate the effect of molasses concentration during immobilization of mixed culture onto the GAC. The molasses concentration using 50 %, 40 %, 30 %, 20 % and 10 % of diluted molasses were used as feedstock in the fermentation process. The maximum hydrogen production of 60 ml was obtained at 30 % of molasses concentration with 831 ppm of hydrogen concentration. Thus, the kinetic parameter obtained from the batch profiling based on modified Gompertz equation are, Hm= 58 ml for the maximum hydrogen production and Rm= 2.02 ml/h representing the hydrogen production rate.

  2. Optimization of the Production of Polygalacturonase from Aspergillus kawachii Cloned in Saccharomyces cerevisiae in Batch and Fed-Batch Cultures

    Directory of Open Access Journals (Sweden)

    Diego Jorge Baruque

    2011-01-01

    Full Text Available Polygalacturonases (PG; EC 3.2.1.15 catalyze the hydrolysis of pectin and/or pectic acid and are useful for industrial applications such as juice clarification and pectin extraction. Growth and heterologous expression of recombinant Saccharomyces cerevisiae which expresses an acidic PG from Aspergillus kawachii has been studied in batch and fed-batch cultures. Kinetics and stoichiometric parameters of the recombinant yeast were determined in batch cultures in a synthetic medium. In these cultures, the total biomass concentration, protein concentration, and enzyme activity achieved were 2.2 g/L, 10 mg/L, and 3 U/mL, respectively, to give a productivity of 0.06 U/(mL·h. In fed-batch cultures, various strategies for galactose feeding were used: (i after a glucose growth phase, the addition of a single pulse of galactose which gave a productivity of 0.19 U/(mL·h; (ii after a glucose growth phase, a double pulse of galactose at the same final concentration was added, resulting in a productivity of 0.21 U/(mL·h; (iii a simultaneous feeding of glucose and galactose, yielding a productivity of 1.32 U/(mL·h. Based on these results, the simultaneous feeding of glucose and galactose was by far the most suitable strategy for the production of this enzyme. Moreover, some biochemical characteristics of the recombinant enzyme such as a molecular mass of ~60 kDa, an isoelectric point of 3.7 and its ability to hydrolyze polygalacturonic acid at pH=2.5 were determined.

  3. Study on Batch Culture Growth Model for Lactococcus lactis IO-1

    OpenAIRE

    Ishizaki, Ayaaki; Ohta, Tomomi; Kobayashi, Genta; 石崎, 文彬; 太田, 智美; 小林, 元太

    1991-01-01

    L-lactate fermentation employing Lactncoccus lactis IO-1 demonstrated a typical end product inhibition. By numerical analysis of fermentation results of the batch culture of this microorganism, the specific rates for cell growth, substrate consumption and product formation were clearly expressed by the end product inhibition formulae. All constants for those formulae were determined by the fermentation results. A mathematical model for batch culture growth of this microorganism in which the n...

  4. Fed-batch CHO cell culture for lab-scale antibody production

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Ley, Daniel; Andersen, Mikael Rørdam

    2017-01-01

    Fed-batch culture is the most commonly used upstream process in industry today for recombinant monoclonal antibody production using Chinese hamster ovary cells. Developing and optimizing this process in the lab is crucial for establishing process knowledge, which enable rapid and predictable tech......-transfer to manufacturing scale. In this chapter, we will describe stepwise how to carry out fed-batch CHO cell culture for lab-scale antibody production....

  5. Production of alpha-amylase in batch and chemostat culture by bacillus stearothermophilus

    Energy Technology Data Exchange (ETDEWEB)

    Davis, P E; Cohen, D L; Whitaker, A

    1980-01-01

    The production of alpha-amylase by a strain of B.stearothermophilus isolated from leaf litter was investigated in a tryptone-maltose medium at 55 degrees in batch and chemostat culture. Amylase production was growth-limited and restricted to the exponential phase in batch culture. The enzyme yield was reduced by 40% when the culture pH was maintained at pH 7.2. Amylase production in chemostat culture was influenced by the growth rate throughout the dilution rate range used.

  6. Xylitol production by Candida parapsilosis under fed-batch culture

    Directory of Open Access Journals (Sweden)

    Sandra A. Furlan

    2001-06-01

    Full Text Available Xylitol production by Candida parapsilosis was investigated under fed-batch cultivation, using single (xylose or mixed (xylose and glucose sugars as substrates. The presence of glucose in the medium induced the production of ethanol as secondary metabolite and improved specific rates of growth, xylitol formation and substrate consumption. Fractionated supply of the feed medium at constant sugar concentration did not promote any increase on the productivity compared to the single batch cultivation.A produção de xylitol por Candida parapsilosis foi investigada em regime de batelada alimentada, usando substratos açucarados de composição simples (xilose ou composta (xilose e glicose. A presença de glicose no meio induziu a formação de etanol como metabólito secundário. A suplementação fracionada do meio de alimentação numa concentração fixa de açúcar não resultou em aumento da produtividade em relação àquela alcançada em batelada simples.

  7. COMETABOLIC DEGRADATION OF CHLOROALLYL ALCOHOLS IN BATCH AND CONTINUOUS CULTURES

    NARCIS (Netherlands)

    VANDERWAARDE, JJ; KOK, R; JANSSEN, DB; Waarde, J.J. van der

    1994-01-01

    The biodegradation of chloroallyl alcohols by pure and mixed bacterial cultures was investigated. Only 2-chloroallyl alcohol and cis- and trans-3-chloroallyl alcohol served as growth substrate for pure cultures. The other chloroallyl alcohols could be cometabolically degraded during growth on

  8. Production of carotenoids and lipids by Rhodococcus opacus PD630 in batch and fed-batch culture.

    Science.gov (United States)

    Thanapimmetha, Anusith; Suwaleerat, Tharatron; Saisriyoot, Maythee; Chisti, Yusuf; Srinophakun, Penjit

    2017-01-01

    Production of carotenoids by Rhodococcus opacus PD630 is reported. A modified mineral salt medium formulated with glycerol as an inexpensive carbon source was used for the fermentation. Ammonium acetate was the nitrogen source. A dry cell mass concentration of nearly 5.4 g/L could be produced in shake flasks with a carotenoid concentration of 0.54 mg/L. In batch culture in a 5 L bioreactor, without pH control, the maximum dry biomass concentration was ~30 % lower than in shake flasks and the carotenoids concentration was 0.09 mg/L. Both the biomass concentration and the carotenoids concentration could be raised using a fed-batch operation with a feed mixture of ammonium acetate and acetic acid. With this strategy, the final biomass concentration was 8.2 g/L and the carotenoids concentration was 0.20 mg/L in a 10-day fermentation. A control of pH proved to be unnecessary for maximizing the production of carotenoids in this fermentation.

  9. One Approach for Dynamic L-lysine Modelling of Repeated Fed-batch Fermentation

    Directory of Open Access Journals (Sweden)

    Kalin Todorov

    2007-03-01

    Full Text Available This article deals with establishment of dynamic unstructured model of variable volume fed-batch fermentation process with intensive droppings for L-lysine production. The presented approach of the investigation includes the following main procedures: description of the process by generalized stoichiometric equations; preliminary data processing and calculation of specific rates for main kinetic variables; identification of the specific rates as a second-order non-linear dynamic models; establishment and optimisation of dynamic model of the process; simulation researches. MATLAB is used as a research environment.

  10. Fructose production by Zymomonas mobilis in fed-batch culture with minimal sorbitol formation

    Energy Technology Data Exchange (ETDEWEB)

    Edye, L A; Johns, M R; Ewings, K N

    1989-08-01

    Fed-batch cultures of Zymomonas mobilis (UQM 2864), a mutant unable to metabolise fructose, grown on diluted sugar cane syrup (200 g/l sucrose) achieved yields of 90.5 g/l fructose and 48.3 g/l ethanol with minimal sorbitol formation and complete utilization of the substrate. The effect of inoculum size on sorbitol formation in the batch stage of fed-batch fermentation are reported. Fermentation of sucrose (350 g/l) supplemented with nutrients yielded 142 g/l fructose and 76.5 g/l ethanol. Some fructose product loss at high fructose concentrations was observed. The fed-batch fermentation process offers a method for obtaining high concentrations of fructose and ethanol from sucrose materials. (orig.).

  11. Increasing the production of desulfurizing biocatalysts by means of fed - batch culture

    International Nuclear Information System (INIS)

    Berdugo, C I; Mena, J A; Acero, J R; Mogollon, L

    2001-01-01

    Over the past years, environmental regulations have driven a lot of effort for the development of new technologies for the upgrading of fossil fuels. Biotechnology offers an alternative way to process fossil fuels by means of a biodesulfurization technology where the production of the biocatalyst is one of the key topics. Traditionally, the production is carried out in batch culture where the maximum cellular concentration is restricted by inherent limitations of the culture type and the microorganism growth rate. This work addresses the production of two desulfurizing microorganisms: Rhodococcus erythropolis IGTS8 and gordona rubropertinctus ICP172 using fed-batch culture. Fed-batch cultures were conducted in a 12 L fermentor using ICP 4 medium containing glucose and DMSO as carbon and sulfur sources. As a result, cell concentration was increased 1.5 and 3 times with fed-batch cultures using constant and exponential flow respectively, achieving a maximum cell concentration of 7.3 g DCW/L of biocatalyst igts8 and 12.85 gGDCW/L of the new biocatalyst ICP172. Both biocatalysts presented biodesulfurization activity in a spiked matrix DBT/HXD and in diesel matrix with the detection of 2-HBP which is the end-product of DBT degradation pathway

  12. Selection of chemically defined media for CHO cell fed-batch culture processes

    NARCIS (Netherlands)

    Pan, X.; Streefland, M.; Dalm, C.; Wijffels, R.H.; Martens, D.E.

    2017-01-01

    Two CHO cell clones derived from the same parental CHOBC cell line and producing the same monoclonal antibody (BC-G, a low producing clone; BC-P, a high producing clone) were tested in four basal media in all possible combinations with three feeds (=12 conditions) in fed-batch cultures.
    Higher

  13. Fed-batch and perfusion culture processes: economic, environmental, and operational feasibility under uncertainty.

    Science.gov (United States)

    Pollock, James; Ho, Sa V; Farid, Suzanne S

    2013-01-01

    This article evaluates the current and future potential of batch and continuous cell culture technologies via a case study based on the commercial manufacture of monoclonal antibodies. The case study compares fed-batch culture to two perfusion technologies: spin-filter perfusion and an emerging perfusion technology utilizing alternating tangential flow (ATF) perfusion. The operational, economic, and environmental feasibility of whole bioprocesses based on these systems was evaluated using a prototype dynamic decision-support tool built at UCL encompassing process economics, discrete-event simulation and uncertainty analysis, and combined with a multi-attribute decision-making technique so as to enable a holistic assessment. The strategies were compared across a range of scales and titres so as to visualize how their ranking changes in different industry scenarios. The deterministic analysis indicated that the ATF perfusion strategy has the potential to offer cost of goods savings of 20% when compared to conventional fed-batch manufacturing processes when a fivefold increase in maximum viable cell densities was assumed. Savings were also seen when the ATF cell density dropped to a threefold increase over the fed-batch strategy for most combinations of titres and production scales. In contrast, the fed-batch strategy performed better in terms of environmental sustainability with a lower water and consumable usage profile. The impact of uncertainty and failure rates on the feasibility of the strategies was explored using Monte Carlo simulation. The risk analysis results demonstrated the enhanced robustness of the fed-batch process but also highlighted that the ATF process was still the most cost-effective option even under uncertainty. The multi-attribute decision-making analysis provided insight into the limited use of spin-filter perfusion strategies in industry. The resulting sensitivity spider plots enabled identification of the critical ratio of weightings of

  14. Perfusion seed cultures improve biopharmaceutical fed-batch production capacity and product quality.

    Science.gov (United States)

    Yang, William C; Lu, Jiuyi; Kwiatkowski, Chris; Yuan, Hang; Kshirsagar, Rashmi; Ryll, Thomas; Huang, Yao-Ming

    2014-01-01

    Volumetric productivity and product quality are two key performance indicators for any biopharmaceutical cell culture process. In this work, we showed proof-of-concept for improving both through the use of alternating tangential flow perfusion seed cultures coupled with high-seed fed-batch production cultures. First, we optimized the perfusion N-1 stage, the seed train bioreactor stage immediately prior to the production bioreactor stage, to minimize the consumption of perfusion media for one CHO cell line and then successfully applied the optimized perfusion process to a different CHO cell line. Exponential growth was observed throughout the N-1 duration, reaching >40 × 10(6) vc/mL at the end of the perfusion N-1 stage. The cultures were subsequently split into high-seed (10 × 10(6) vc/mL) fed-batch production cultures. This strategy significantly shortened the culture duration. The high-seed fed-batch production processes for cell lines A and B reached 5 g/L titer in 12 days, while their respective low-seed processes reached the same titer in 17 days. The shortened production culture duration potentially generates a 30% increase in manufacturing capacity while yielding comparable product quality. When perfusion N-1 and high-seed fed-batch production were applied to cell line C, higher levels of the active protein were obtained, compared to the low-seed process. This, combined with correspondingly lower levels of the inactive species, can enhance the overall process yield for the active species. Using three different CHO cell lines, we showed that perfusion seed cultures can optimize capacity utilization and improve process efficiency by increasing volumetric productivity while maintaining or improving product quality. © 2014 American Institute of Chemical Engineers.

  15. Production of nattokinase by high cell density fed-batch culture of Bacillus subtilis.

    Science.gov (United States)

    Kwon, Eun-Yeong; Kim, Kyung Mi; Kim, Mi Kyoung; Lee, In Young; Kim, Beom Soo

    2011-09-01

    Bacillus subtilis was cultivated to high cell density for nattokinase production by pH-stat fed-batch culture. A concentrated mixture solution of glucose and peptone was automatically added by acid-supplying pump when culture pH rose above high limit. Effect of the ratio of glucose to peptone in feeding solution was investigated on cell growth and nattokinase production by changing the ratio from 0.2 to 5 g glucose/g peptone. The highest cell concentration was 77 g/L when the ratio was 0.2 g glucose/g peptone. Cell concentration decreased with increasing the ratio of glucose to peptone in feeding solution, while the optimum condition existed for nattokinase production. The highest nattokinase activity was 14,500 unit/mL at a ratio of 0.33 g glucose/g peptone, which was 4.3 times higher than that in batch culture.

  16. Oxygen availability strongly affects chronological lifespan and thermotolerance in batch cultures of Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Markus M.M. Bisschops

    2015-10-01

    Full Text Available Stationary-phase (SP batch cultures of Saccharomyces cerevisiae, in which growth has been arrested by carbon-source depletion, are widely applied to study chronological lifespan, quiescence and SP-associated robustness. Based on this type of experiments, typically performed under aerobic conditions, several roles of oxygen in aging have been proposed. However, SP in anaerobic yeast cultures has not been investigated in detail. Here, we use the unique capability of S. cerevisiae to grow in the complete absence of oxygen to directly compare SP in aerobic and anaerobic bioreactor cultures. This comparison revealed strong positive effects of oxygen availability on adenylate energy charge, longevity and thermotolerance during SP. A low thermotolerance of anaerobic batch cultures was already evident during the exponential growth phase and, in contrast to the situation in aerobic cultures, was not substantially increased during transition into SP. A combination of physiological and transcriptome analysis showed that the slow post-diauxic growth phase on ethanol, which precedes SP in aerobic, but not in anaerobic cultures, endowed cells with the time and resources needed for inducing longevity and thermotolerance. When combined with literature data on acquisition of longevity and thermotolerance in retentostat cultures, the present study indicates that the fast transition from glucose excess to SP in anaerobic cultures precludes acquisition of longevity and thermotolerance. Moreover, this study demonstrates the importance of a preceding, calorie-restricted conditioning phase in the acquisition of longevity and stress tolerance in SP yeast cultures, irrespective of oxygen availability.

  17. Identifying yeast isolated from spoiled peach puree and assessment of its batch culture for invertase production

    Directory of Open Access Journals (Sweden)

    Marcela Vega FERREIRA

    Full Text Available Abstract The identification of yeasts isolated from spoiled Jubileu peach puree using the API 20C AUX method and a commercial yeast as witness were studied. Subsequently, the yeast’s growth potential using two batch culture treatments were performed to evaluate number of colonies (N, reducing sugar concentration (RS, free-invertase (FI, and culture-invertase activity (CI. Stock cultures were maintained on potato dextrose agar (PDA slants at 4 °C and pH 5 for later use for batch-culture (150 rpm at 30°C for 24 h, then they were stored at 4 °C for subsequent invertase extraction. The FI extract was obtained using NaHCO3 as autolysis agent, and CI activity was determined on the supernatant after batch-cultured centrifugation. The activity was followed by an increase in absorbance at 490 nm using the acid 3,5-DNS method with glucose standard. Of the four yeasts identified, Saccharomyces cerevisiae was chosen for legal reasons. It showed logarithmic growth up to 18 h of fermentation with positive correlation CI activity and inverse with RS. FI showed greater activity by the end of the log phase and an inverse correlation with CI activity. Finally, it was concluded that treatment “A” is more effective than “B” to produce invertase (EC 3.2.1.26.

  18. Monitoring and robust adaptive control of fed-batch cultures of microorganisms exhibiting overflow metabolism [abstract

    Directory of Open Access Journals (Sweden)

    Vande Wouwer, A.

    2010-01-01

    Full Text Available Overflow metabolism characterizes cells strains that are likely to produce inhibiting by-products resulting from an excess of substrate feeding and a saturated respiratory capacity. The critical substrate level separating the two different metabolic pathways is generally not well defined. Monitoring of this kind of cultures, going from model identification to state estimation, is first discussed. Then, a review of control techniques which all aim at maximizing the cell productivity of fed-batch fermentations is presented. Two main adaptive control strategies, one using an estimation of the critical substrate level as set-point and another regulating the by-product concentration, are proposed. Finally, experimental investigations of an adaptive RST control scheme using the observer polynomial for the regulation of the ethanol concentration in Saccharomyces cerevisiae fed-batch cultures ranging from laboratory to industrial scales, are also presented.

  19. Nonlinear impulsive system of fed-batch culture in fermentative production and its properties

    International Nuclear Information System (INIS)

    Gao Caixia; Li Kezan; Feng Enmin; Xiu Zhilong

    2006-01-01

    In this study, the nonlinear dynamical system of fed-batch fermentation is investigated in the process of bio-dissimilation of glycerol to 1,3-propanediol by Klebsiella pneumoniae. Considering the abrupt increase of glycerol in fed-batch culture, this paper proposes a nonlinear impulsive system of the culture process, which is fit for formulating the factual fermentation better than the continuous models in being. We study the questions of existence and properties of mild solutions for the system and the continuous dependence of solutions on initial values and the controllable variable. Finally, the numerical simulations show that the errors between experimental and computational values using the impulsive system are less than those using the previous continuous system

  20. Batch culture of Azotobacter vinelandii under oxygen limitation conditionS

    Energy Technology Data Exchange (ETDEWEB)

    Camacho Rubio, F.; Martinez Nieto, L.; Fernandez Serrano, M.; Jimenez Moleon, M.C. [Departamento de Ingenieria Quimica, Universidad de Granada, Granada (Spain)

    1996-12-01

    The batch culture of Azotobacter vinealandii on glucose under nitrogen-fixing conditions, seeking oxygen limitation conditions, has been studied in order to use it as a Biological Test System for the experimental study of oxygen transfer enhancement methods in aerobic fermenters. overall kinetic parameters for exponential growth and for linear growth (under oxygen limitation) have been determined. It was noted an appreciable influence of the oxygen transfer rate on glucose and oxygen uptake, which seems to be due to alginate production, excreted as a nitrogenase protection mechanisms. (Author) 12 refs.

  1. Biological treatment of potato processing wastewater for red pigment production by immobilized cells of UV-irradiated monascus sp. in repeated batch

    International Nuclear Information System (INIS)

    Khalaf, S.A.

    2004-01-01

    Potato processing wastewater (PPW) was collected and analyzed for biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen and starch content. A fungal strain isolated from PPW identified as Monascus sp. PPW was evaluated for its ability to grow and produce red pigment, biomass and reduce the starch content of the ,PPW. Active UV-irradiated isolate of the above strain was obtained by exposing the parent strain to UV-radiation and coded Monascus. sp. PPW-UV7 and used as immobilized cell system for PPW treatment process in repeated batch fermentation. The immobilized cells (in sponge cubes) were able to reduce COD by about 85.7 %, with biomass production of 9.22 gl+ l and over productivity of red pigment of 2.6 gl+ 1 after 8 days fermentation (2 batches). The immobilized cells showed stability and viability for 8 batches (32 days) during the process treatment

  2. Time-dependent radiation characteristics of Nannochloropsis oculata during batch culture

    International Nuclear Information System (INIS)

    Heng, Ri-Liang; Pilon, Laurent

    2014-01-01

    This paper reports the temporal evolution of the scattering and absorbing cross-sections of marine eustigmatophycease Nannochloropsis oculata grown in a flat-plate photobioreactor (PBR). The PBR was operated in batch mode under constant irradiance of 7500 or 10,000 lux provided by red LEDs emitting at 630 nm. The radiation characteristics between 400 and 750 nm and pigment concentrations of N. oculata were measured systematically every 24 h for up to 18 days. They were found to vary significantly with time in response to changes in light and nutrients availability. The results were interpreted in terms of up- and down-regulations of pigments and other intracellular components. Finally, this study demonstrates that the light transfer in the PBR could be predicted using constant radiation characteristics measured during the exponential growth phase with reasonable accuracy provided that the cultures were not nitrogen limited. During nitrogen starvation, pigment concentrations decreased and radiation characteristics evolved rapidly. These results will be useful in the design and operation of PBRs for biofuel production at both small and large scales. - Highlights: • N. oculata cultures were grown in batch mode under two different irradiances. • Temporal evolution of their absorption and scattering cross-sections was reported. • The effects of photoacclimation and nitrogen starvation were quantified. • Results were interpreted in terms of regulation of cell constituents

  3. Concentrated fed-batch cell culture increases manufacturing capacity without additional volumetric capacity.

    Science.gov (United States)

    Yang, William C; Minkler, Daniel F; Kshirsagar, Rashmi; Ryll, Thomas; Huang, Yao-Ming

    2016-01-10

    Biomanufacturing factories of the future are transitioning from large, single-product facilities toward smaller, multi-product, flexible facilities. Flexible capacity allows companies to adapt to ever-changing pipeline and market demands. Concentrated fed-batch (CFB) cell culture enables flexible manufacturing capacity with limited volumetric capacity; it intensifies cell culture titers such that the output of a smaller facility can rival that of a larger facility. We tested this hypothesis at bench scale by developing a feeding strategy for CFB and applying it to two cell lines. CFB improved cell line A output by 105% and cell line B output by 70% compared to traditional fed-batch (TFB) processes. CFB did not greatly change cell line A product quality, but it improved cell line B charge heterogeneity, suggesting that CFB has both process and product quality benefits. We projected CFB output gains in the context of a 2000-L small-scale facility, but the output was lower than that of a 15,000-L large-scale TFB facility. CFB's high cell mass also complicated operations, eroded volumetric productivity, and showed our current processes require significant improvements in specific productivity in order to realize their full potential and savings in manufacturing. Thus, improving specific productivity can resolve CFB's cost, scale-up, and operability challenges. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Photosynthetic light reactions increase total lipid accumulation in carbon-supplemented batch cultures of Chlorella vulgaris.

    Science.gov (United States)

    Woodworth, Benjamin D; Mead, Rebecca L; Nichols, Courtney N; Kolling, Derrick R J

    2015-03-01

    Microalgae are an attractive biofuel feedstock because of their high lipid to biomass ratios, lipid compositions that are suitable for biodiesel production, and the ability to grow on varied carbon sources. While algae can grow autotrophically, supplying an exogenous carbon source can increase growth rates and allow heterotrophic growth in the absence of light. Time course analyses of dextrose-supplemented Chlorella vulgaris batch cultures demonstrate that light availability directly influences growth rate, chlorophyll production, and total lipid accumulation. Parallel photomixotrophic and heterotrophic cultures grown to stationary phase reached the same amount of biomass, but total lipid content was higher for algae grown in the presence of light (an average of 1.90 mg/mL vs. 0.77 mg/mL over 5 days of stationary phase growth). Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. The mechanism of improved pullulan production by nitrogen limitation in batch culture of Aureobasidium pullulans.

    Science.gov (United States)

    Wang, Dahui; Chen, Feifei; Wei, Gongyuan; Jiang, Min; Dong, Mingsheng

    2015-08-20

    Batch culture of Aureobasidium pullulans CCTCC M 2012259 for pullulan production at different concentrations of ammonium sulfate and yeast extract was investigated. Increased pullulan production was obtained under nitrogen-limiting conditions, as compared to that without nitrogen limitation. The mechanism of nitrogen limitation favoring to pullulan overproduction was revealed by determining the activity as well as gene expression of key enzymes, and energy supply for pullulan biosynthesis. Results indicated that nitrogen limitation increased the activities of α-phosphoglucose mutase and glucosyltransferase, up-regulated the transcriptional levels of pgm1 and fks genes, and supplied more ATP intracellularly, which were propitious to further pullulan biosynthesis. The economic analysis of batch pullulan production indicated that nitrogen limitation could reduce more than one third of the cost of raw materials when glucose was supplemented to a total concentration of 70 g/L. This study also helps to understand the mechanism of other polysaccharide overproduction by nitrogen limitation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Macroscopic Dynamic Modeling of Sequential Batch Cultures of Hybridoma Cells: An Experimental Validation

    Directory of Open Access Journals (Sweden)

    Laurent Dewasme

    2017-02-01

    Full Text Available Hybridoma cells are commonly grown for the production of monoclonal antibodies (MAb. For monitoring and control purposes of the bioreactors, dynamic models of the cultures are required. However these models are difficult to infer from the usually limited amount of available experimental data and do not focus on target protein production optimization. This paper explores an experimental case study where hybridoma cells are grown in a sequential batch reactor. The simplest macroscopic reaction scheme translating the data is first derived using a maximum likelihood principal component analysis. Subsequently, nonlinear least-squares estimation is used to determine the kinetic laws. The resulting dynamic model reproduces quite satisfactorily the experimental data, as evidenced in direct and cross-validation tests. Furthermore, model predictions can also be used to predict optimal medium renewal time and composition.

  7. Effect of chito-oligosaccharides over human faecal microbiota during fermentation in batch cultures.

    Science.gov (United States)

    Mateos-Aparicio, Inmaculada; Mengíbar, Marian; Heras, Angeles

    2016-02-10

    Chitosan with high number of deacetylated units, its reacetylated derivative and COS obtained through an enzymatic treatment with chitosanase were tested in pH controlled batch cultures to investigate the ability of the human faecal microbiota to utilise them. Chitosan derivatives with high number of deacetylated units decreased the bacterial populations: Bifidobacterium spp., Eubacterium rectale/Clostridium coccoides, C. Histolyticum and Bacteroides/Prevotella. On the other hand, chitosan derivatives with high content of acetylated residues maintained the tested bacterial groups and could increase Lactobacillus/Enterococcus. Regarding short chain fatty acids (SCFA), only low Mw COS increased the production in similar levels than fructo-oligossacharides (FOS). The acetylated chitosans and their COS do not appear as potential prebiotics but did not affect negatively the faecal microbiota, while derivatives with high number of deacetylated units could induce a colonic microbiota imbalance. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Perfusion cell culture decreases process and product heterogeneity in a head-to-head comparison with fed-batch.

    Science.gov (United States)

    Walther, Jason; Lu, Jiuyi; Hollenbach, Myles; Yu, Marcella; Hwang, Chris; McLarty, Jean; Brower, Kevin

    2018-05-30

    In this study, we compared the impacts of fed-batch and perfusion platforms on process and product attributes for IgG1- and IgG4-producing cell lines. A "plug-and-play" approach was applied to both platforms at bench scale, using commercially available basal and feed media, a standard feed strategy for fed-batch, and ATF filtration for perfusion. Product concentration in fed-batch was 2.5 times greater than perfusion, while average productivity in perfusion was 7.5 times greater than fed-batch. PCA revealed more variability in the cell environment and metabolism during the fed-batch run. LDH measurements showed that exposure of product to cell lysate was 7-10 times greater in fed-batch. Product analysis shows larger abundances of neutral species in perfusion, likely due to decreased bioreactor residence times and extracellular exposure. The IgG1 perfusion product also had higher purity and lower half-antibody. Glycosylation was similar across both culture modes. The first perfusion harvest slice for both product types showed different glycosylation than subsequent harvests, suggesting that product quality lags behind metabolism. In conclusion, process and product data indicate that intra-lot heterogeneity is decreased in perfusion cultures. Additional data and discussion is required to understand the developmental, clinical and commercial implications, and in what situations increased uniformity would be beneficial. This article is protected by copyright. All rights reserved.

  9. Amino acid and glucose metabolism in fed-batch CHO cell culture affects antibody production and glycosylation

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian

    2015-01-01

    optimization, especially media optimization. Gaining knowledge on their interrelations could provide insight for obtaining higher immunoglobulin G (IgG) titer and better controlling glycosylationrelated product quality. In this work, different fed-batch processes with two chemically defined proprietary media......Fed-batch Chinese hamster ovary (CHO) cell culture is the most commonly used process for IgG production in the biopharmaceutical industry. Amino acid and glucose consumption, cell growth, metabolism, antibody titer, and N-glycosylation patterns are always the major concerns during upstream process...... and glutamine concentrations and uptake rates were positively correlated with intracellular UDP-Gal availability. All these findings are important for optimization of fed-batch culture for improving IgG production and directing glycosylation quality....

  10. Fed-batch culture for the direct conversion of cellulosic substrates to acetic acid/ethanol by Fusarium oxysporum

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, P.K.R.; Singh, A.; Schuegerl, K. (Hannover Univ. (Germany). Inst. fuer Technische Chemie)

    1991-01-01

    The production of acetic acid/ethanol and hydrolytic enzymes from potato waste (cellulosic waste from potato starch industries) by Fusarium oxysporum 841 was improved considerably by using fed-batch culture. In this, two types of feed policies were adopted consisting of different substrate concentrations and feeding times. In fed-batch culture, the enzymes tested, namely avicelase, CMCase, cellobiase and xylanase, showed significant improvements over batch fermentations with regard to enzyme titres and productivities. The maximum concentration, yield and productivity of acetic acid were 22.5 g litre{sup -1}, 0.38 g (g {sub strate}){sup -1} and 0.09 g litre{sup -1} h{sup -1}, respectively, and these values for ethanol were 5.7 g litre{sup -1}, 0.1 g (g substrate){sup -1} and 0.03 g litre{sup -1}h{sup -1}, respectively. (author).

  11. Lactic acid production from potato peel waste by anaerobic sequencing batch fermentation using undefined mixed culture.

    Science.gov (United States)

    Liang, Shaobo; McDonald, Armando G; Coats, Erik R

    2015-11-01

    Lactic acid (LA) is a necessary industrial feedstock for producing the bioplastic, polylactic acid (PLA), which is currently produced by pure culture fermentation of food carbohydrates. This work presents an alternative to produce LA from potato peel waste (PPW) by anaerobic fermentation in a sequencing batch reactor (SBR) inoculated with undefined mixed culture from a municipal wastewater treatment plant. A statistical design of experiments approach was employed using set of 0.8L SBRs using gelatinized PPW at a solids content range from 30 to 50 g L(-1), solids retention time of 2-4 days for yield and productivity optimization. The maximum LA production yield of 0.25 g g(-1) PPW and highest productivity of 125 mg g(-1) d(-1) were achieved. A scale-up SBR trial using neat gelatinized PPW (at 80 g L(-1) solids content) at the 3 L scale was employed and the highest LA yield of 0.14 g g(-1) PPW and a productivity of 138 mg g(-1) d(-1) were achieved with a 1 d SRT. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Acid protease and formation of multiple forms of glucoamylase in batch and continuous cultures of Aspergillus niger

    DEFF Research Database (Denmark)

    Aalbæk, Thomas; Reeslev, Morten; Jensen, Bo

    2002-01-01

    with molecular weights of approx. 91 (GAI), 73 (GAII), and 59 kDa (GAIII). Data from batch fermentations with constant pH 3.0 and 5.0 showed a uniform distribution of extracellular GA forms throughout the fermentations and independent of culture growth phases. Furthermore, steady-state data from chemostat...

  13. Degradation of toluene and trichloroethylene by Burkholderia cepacia G4 in growth-limited fed-batch culture

    NARCIS (Netherlands)

    Mars, Astrid E.; Houwing, Joukje; Dolfing, Jan; Janssen, Dick B.

    Burkholderia (Pseudomonas) cepacia G4 was cultivated in a fed-batch bioreactor on either toluene or toluene plus trichloroethylene (TCE), The culture was allowed to reach a constant cell density under conditions in which the amount of toluene supplied equals the maintenance energy demand of the

  14. Optimization of culture conditions for biological hydrogen production by Citrobacter freundii CWBI952 in batch, sequenced-batch and semicontinuous operating mode

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, Christopher; Hiligsmann, Serge; Beckers, Laurent; Masset, Julien; Thonart, Philippe [Walloon Centre of Industrial Biology, Bd du Rectorat, 29, B.40 - P.70, B-4000 Liege (Belgium); Wilmotte, Annick [Center for Protein Engineering, Institute of Chemistry, B.6-P.14, B-4000 Liege (Belgium)

    2010-02-15

    Investigations were carried out to determine the effect of the pH, the nitrogen source, iron and the dilution rate (h{sup -1}) on fermentative hydrogen production from glucose by the newly isolated strain Citrobacter freundii CWBI952. The hydrogen production rate (HPR), hydrogen yield, biomass and soluble metabolites were monitored at 30 C in 100 mL serum bottles and in a 2.3 L bioreactor operated in batch, sequenced-batch and semicontinuous mode. The results indicate that hydrogen production activity, formate biosynthesis and glucose intake rates are very sensitive to the culture pH, and that additional formate bioconversion and production of hydrogen with lower biomass yields can be obtained at pH 5.9. In a further series of cultures casein peptone was replaced by (NH{sub 4}){sub 2}SO{sub 4}, a low cost alternative nitrogen source. The ammonia-based substitute was found to be suitable for H{sub 2} production when a concentration of 0.045 g/L FeSO{sub 4} was provided. Optimal overall performances (ca. an HPR of 33.2 mL H{sub 2}/L h and a yield of 0.83mol{sub H{sub 2}}/mol{sub glucose}) were obtained in the semicontinuous culture applying the previously optimized parameters for pH, nitrogen, and iron with a dilution rate of 0.012 h{sup -1} and degassing of biogas by N{sub 2} at a 28 mL/min flow rate. (author)

  15. Modelling of L-valine Repeated Fed-batch Fermentation Process Taking into Account the Dissolved Oxygen Tension

    Directory of Open Access Journals (Sweden)

    Tzanko Georgiev

    2009-03-01

    Full Text Available This article deals with synthesis of dynamic unstructured model of variable volume fed-batch fermentation process with intensive droppings for L-valine production. The presented approach of the investigation includes the following main procedures: description of the process by generalized stoichiometric equations; preliminary data processing and calculation of specific rates for main kinetic variables; identification of the specific rates takes into account the dissolved oxygen tension; establishment and optimisation of dynamic model of the process; simulation researches. MATLAB is used as a research environment.

  16. The use of date waste for lactic acid production by a fed-batch culture using Lactobacillus casei subsp. rhamnosus.

    Science.gov (United States)

    Nancib, Aicha; Nancib, Nabil; Boubendir, Abdelhafid; Boudrant, Joseph

    2015-01-01

    The production of lactic acid from date juice by Lactobacillus caseisubsp. rhamnosus in batch and fed-batch cultures has been investigated. The fed-batch culture system gave better results for lactic acid production and volumetric productivity. The aim of this work is to determine the effects of the feeding rate and the concentration of the feeding medium containing date juice glucose on the cell growth, the consumption of glucose and the lactic acid production by Lactobacillus casei subsp. rhamnosus in fed-batch cultures. For this study, two concentrations of the feeding medium (62 and 100 g/L of date juice glucose) were tested at different feeding rates (18, 22, 33, 75 and 150 mL/h). The highest volumetric productivity (1.3 g/L.h) and lactic acid yield (1.7 g/g) were obtained at a feeding rate of 33 mL/h and a date juice glucose concentration of 62 g/L in the feeding medium. As a result, most of the date juice glucose was completely utilised (residual glucose 1 g/L), and a maximum lactic acid production level (89.2 g/L) was obtained.

  17. The effects of furfural on ethanol production by Saccharomyces cerevisiae in batch culture

    Energy Technology Data Exchange (ETDEWEB)

    Boyer, L.J.; Vega, J.L.; Klasson, K.T.; Clausen, E.C.; Gaddy, J.L. (Arkansas Univ., Fayetteville, AR (US). Dept. of Chemical Engineering)

    1992-01-01

    Browning reaction products such as furfural and 5-hydroxy-methyl-furfural (HMF) have been shown to inhibit microbial growth and metabolism in ethanol fermentations using Saccharomyces cerevisiae. This paper quantifies the extent of furfural inhibition and yeast growth, glucose utilization, and ethanol production as a function of inoculum size (0.1-9 gl{sup -1}). Batch culture experiments were conducted using furfural concentrations in the range of 0 to 2.0 gl{sup -1} and mathematical correlations were proposed and tested. The results indicate that the specific growth rate decreased with increasing furfural concentration and inoculum size, while the maintenance coefficients were unaffected. The apparent and true cell yield coefficients on glucose were depressed with the addition of furfural. Specific production rates were unaffected at the furfural levels used but ethanol inhibition was apparent. The specific production rate was less inhibited by ethanol at higher inoculum sizes. Global specific productivities were not affected by the presence of furfural. At a 0.1 gl{sup -1} inoculum size, furfural depletion was complete within 15-20 h, depending upon the furfural concentration employed. At higher incoculum levels (2-9 gl{sup -1}), all furfural was depleted in less than 5 h. (author).

  18. Beware batch culture: Seasonality and niche construction predicted to favor bacterial adaptive diversification.

    Directory of Open Access Journals (Sweden)

    Charles Rocabert

    2017-03-01

    Full Text Available Metabolic cross-feeding interactions between microbial strains are common in nature, and emerge during evolution experiments in the laboratory, even in homogeneous environments providing a single carbon source. In sympatry, when the environment is well-mixed, the reasons why emerging cross-feeding interactions may sometimes become stable and lead to monophyletic genotypic clusters occupying specific niches, named ecotypes, remain unclear. As an alternative to evolution experiments in the laboratory, we developed Evo2Sim, a multi-scale model of in silico experimental evolution, equipped with the whole tool case of experimental setups, competition assays, phylogenetic analysis, and, most importantly, allowing for evolvable ecological interactions. Digital organisms with an evolvable genome structure encoding an evolvable metabolic network evolved for tens of thousands of generations in environments mimicking the dynamics of real controlled environments, including chemostat or batch culture providing a single limiting resource. We show here that the evolution of stable cross-feeding interactions requires seasonal batch conditions. In this case, adaptive diversification events result in two stably co-existing ecotypes, with one feeding on the primary resource and the other on by-products. We show that the regularity of serial transfers is essential for the maintenance of the polymorphism, as it allows for at least two stable seasons and thus two temporal niches. A first season is externally generated by the transfer into fresh medium, while a second one is internally generated by niche construction as the provided nutrient is replaced by secreted by-products derived from bacterial growth. In chemostat conditions, even if cross-feeding interactions emerge, they are not stable on the long-term because fitter mutants eventually invade the whole population. We also show that the long-term evolution of the two stable ecotypes leads to character

  19. Inventing Japan's 'robotics culture': the repeated assembly of science, technology, and culture in social robotics.

    Science.gov (United States)

    Sabanović, Selma

    2014-06-01

    Using interviews, participant observation, and published documents, this article analyzes the co-construction of robotics and culture in Japan through the technical discourse and practices of robotics researchers. Three cases from current robotics research--the seal-like robot PARO, the Humanoid Robotics Project HRP-2 humanoid, and 'kansei robotics' - show the different ways in which scientists invoke culture to provide epistemological grounding and possibilities for social acceptance of their work. These examples show how the production and consumption of social robotic technologies are associated with traditional crafts and values, how roboticists negotiate among social, technical, and cultural constraints while designing robots, and how humans and robots are constructed as cultural subjects in social robotics discourse. The conceptual focus is on the repeated assembly of cultural models of social behavior, organization, cognition, and technology through roboticists' narratives about the development of advanced robotic technologies. This article provides a picture of robotics as the dynamic construction of technology and culture and concludes with a discussion of the limits and possibilities of this vision in promoting a culturally situated understanding of technology and a multicultural view of science.

  20. Exposing Students to Repeat Photography: Increasing Cultural Understanding on a Short-Term Study Abroad

    Science.gov (United States)

    Lemmons, Kelly K.; Brannstrom, Christian; Hurd, Danielle

    2014-01-01

    Traditionally, repeat photography has been used to analyze land cover change. This paper describes how repeat photography may be used as a tool to enhance the short-term study abroad experience by facilitating cultural interaction and understanding. We present evidence from two cases and suggest a five-step repeat photography method for educators…

  1. Ethanol production by repeated batch and continuous fermentations of blackstrap molasses using immobilized yeast cells on thin-shell silk cocoons

    International Nuclear Information System (INIS)

    Rattanapan, Anuchit; Limtong, Savitree; Phisalaphong, Muenduen

    2011-01-01

    Highlights: → Thin-shell silk cocoons for immobilization of Saccharomycescerevisiae. → Advantages: high mechanical strength, light weight, biocompatibility and high surface area. → Enhanced cell stability and ethanol productivity by the immobilization system. -- Abstract: A thin-shell silk cocoon (TSC), a residual from the silk industry, is used as a support material for the immobilization of Saccharomyces cerevisiae M30 in ethanol fermentation because of its properties such as high mechanical strength, light weight, biocompatibility and high surface area. In batch fermentation with blackstrap molasses as the main fermentation substrate, an optimal ethanol concentration of 98.6 g/L was obtained using a TSC-immobilized cell system at an initial reducing sugar concentration of 240 g/L. The ethanol concentration produced by the immobilized cells was 11.5% higher than that produced by the free cells. Ethanol production in five-cycle repeated batch fermentation demonstrated the enhanced stability of the immobilized yeast cells. Under continuous fermentation in a packed-bed reactor, a maximum ethanol productivity of 19.0 g/(L h) with an ethanol concentration of 52.8 g/L was observed at a 0.36 h -1 dilution rate.

  2. Long-term effect of inoculum pretreatment on fermentative hydrogen production by repeated batch cultivations: homoacetogenesis and methanogenesis as competitors to hydrogen production

    DEFF Research Database (Denmark)

    Luo, Gang; Karakashev, Dimitar Borisov; Xie, Li

    2011-01-01

    Long-term effects of inoculum pretreatments(heat, acid, loading-shock) on hydrogen production from glucose under different temperatures (378C, 558C) and initial pH (7 and 5.5) were studied by repeated batch cultivations. Results obtained showed that it was necessary to investigate the long......-term effect of inoculum pretreatment on hydrogen production since pretreatments may just temporarily inhibit the hydrogen consuming processes. After long-term cultivation, pretreated inocula did not enhance hydrogen production compared to untreated inocula under mesophilic conditions (initial pH 7 and pH 5.......5) and thermophilic conditions (initial pH 7). However, pretreatment could inhibit lactate production and lead to higher hydrogen yield under thermophilic conditions at initial pH 5.5. The results further demonstrated that inoculum pretreatment could not permanently inhibit either methanogenesis or homoacetogenesis...

  3. A novel process-based model of microbial growth: self-inhibition in Saccharomyces cerevisiae aerobic fed-batch cultures.

    Science.gov (United States)

    Mazzoleni, Stefano; Landi, Carmine; Cartenì, Fabrizio; de Alteriis, Elisabetta; Giannino, Francesco; Paciello, Lucia; Parascandola, Palma

    2015-07-30

    Microbial population dynamics in bioreactors depend on both nutrients availability and changes in the growth environment. Research is still ongoing on the optimization of bioreactor yields focusing on the increase of the maximum achievable cell density. A new process-based model is proposed to describe the aerobic growth of Saccharomyces cerevisiae cultured on glucose as carbon and energy source. The model considers the main metabolic routes of glucose assimilation (fermentation to ethanol and respiration) and the occurrence of inhibition due to the accumulation of both ethanol and other self-produced toxic compounds in the medium. Model simulations reproduced data from classic and new experiments of yeast growth in batch and fed-batch cultures. Model and experimental results showed that the growth decline observed in prolonged fed-batch cultures had to be ascribed to self-produced inhibitory compounds other than ethanol. The presented results clarify the dynamics of microbial growth under different feeding conditions and highlight the relevance of the negative feedback by self-produced inhibitory compounds on the maximum cell densities achieved in a bioreactor.

  4. Acid protease and formation of multiple forms of glycoamylase in batch and continuous cultures of Aspergillus niger

    DEFF Research Database (Denmark)

    Aalbæk, Thomas; Reeslev, Morten; Jensen, Bo

    2002-01-01

    In order to identify factors responsible for production of multiple forms of glucoamylase (GA) by Aspergillus niger Bo-1, the fungus was cultured in both complex and defined media in pH-controlled batch fermenters and chemostats. At all culture conditions three forms of GA were produced...... degradation of the GA forms at low pH. It was concluded that the observed modifications of the extracellular profile of GA isoforms in A. niger Bo-1 are due to changes in pH and medium composition....

  5. Pilot scale repeated fed-batch fermentation processes of the wine yeast Dekkera bruxellensis for mass production of resveratrol from Polygonum cuspidatum.

    Science.gov (United States)

    Kuo, Hsiao-Ping; Wang, Reuben; Lin, Yi-Sheng; Lai, Jinn-Tsyy; Lo, Yi-Chen; Huang, Shyue-Tsong

    2017-11-01

    Resveratrol has long been used as an ingredient in functional foods. Currently, Polygonum cuspidatum extract is the greatest natural source for resveratrol because of high concentrations of glycosidic-linked resveratrol. Thus, developing a cost-effective procedure to hydrolyze glucoside could substantially enhance resveratrol production from P. cuspidatum. This study selected Dekkera bruxellensis from several microorganisms based on its bioconversion and enzyme-specific activities. We demonstrated that the cells could be reused at least nine times while maintaining an average of 180.67U/L β-glucosidase activity. The average resveratrol bioconversion efficiency within five rounds of repeated usage was 108.77±0.88%. This process worked effectively when the volume was increased to 1200L, a volume at which approximately 35mgL -1 h -1 resveratrol per round was produced. This repeated fed-batch bioconversion process for resveratrol production is comparable to enzyme or cell immobilization strategies in terms of reusing cycles, but without incurring additional costs for immobilization. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Modeling growth, lipid accumulation and lipid turnover in submerged batch cultures of Umbelopsis isabellina

    NARCIS (Netherlands)

    Meeuwse, P.; Akbari, P.; Tramper, J.; Rinzema, A.

    2012-01-01

    The production of lipids by oleaginous yeast and fungi becomes more important because these lipids can be used for biodiesel production. To understand the process of lipid production better, we developed a model for growth, lipid production and lipid turnover in submerged batch fermentation. This

  7. Amino acid and glucose metabolism in fed-batch CHO cell culture affects antibody production and glycosylation.

    Science.gov (United States)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian; Wagtberg Sen, Jette; Rasmussen, Søren Kofoed; Kontoravdi, Cleo; Weilguny, Dietmar; Andersen, Mikael Rørdam

    2015-03-01

    Fed-batch Chinese hamster ovary (CHO) cell culture is the most commonly used process for IgG production in the biopharmaceutical industry. Amino acid and glucose consumption, cell growth, metabolism, antibody titer, and N-glycosylation patterns are always the major concerns during upstream process optimization, especially media optimization. Gaining knowledge on their interrelations could provide insight for obtaining higher immunoglobulin G (IgG) titer and better controlling glycosylation-related product quality. In this work, different fed-batch processes with two chemically defined proprietary media and feeds were studied using two IgG-producing cell lines. Our results indicate that the balance of glucose and amino acid concentration in the culture is important for cell growth, IgG titer and N-glycosylation. Accordingly, the ideal fate of glucose and amino acids in the culture could be mainly towards energy and recombinant product, respectively. Accumulation of by-products such as NH4(+) and lactate as a consequence of unbalanced nutrient supply to cell activities inhibits cell growth. The levels of Leu and Arg in the culture, which relate to cell growth and IgG productivity, need to be well controlled. Amino acids with the highest consumption rates correlate with the most abundant amino acids present in the produced IgG, and thus require sufficient availability during culture. Case-by-case analysis is necessary for understanding the effect of media and process optimization on glycosylation. We found that in certain cases the presence of Man5 glycan can be linked to limitation of UDP-GlcNAc biosynthesis as a result of insufficient extracellular Gln. However, under different culture conditions, high Man5 levels can also result from low α-1,3-mannosyl-glycoprotein 2-β-N-acetylglucosaminyltransferase (GnTI) and UDP-GlcNAc transporter activities, which may be attributed to high level of NH4+ in the cell culture. Furthermore, galactosylation of the mAb Fc glycans

  8. Benzoate-induced stress enhances xylitol yield in aerobic fed-batch culture of Candida mogii TISTR 5892.

    Science.gov (United States)

    Wannawilai, Siwaporn; Sirisansaneeyakul, Sarote; Chisti, Yusuf

    2015-01-20

    Production of the natural sweetener xylitol from xylose via the yeast Candida mogii TISTR 5892 was compared with and without the growth inhibitor sodium benzoate in the culture medium. Sodium benzoate proved to be an uncompetitive inhibitor in relatively poorly oxygenated shake flask aerobic cultures. In a better controlled aerobic environment of a bioreactor, the role of sodium benzoate could equally well be described as competitive, uncompetitive or noncompetitive inhibitor of growth. In intermittent fed-batch fermentations under highly aerobic conditions, the presence of sodium benzoate at 0.15gL(-1) clearly enhanced the xylitol titer relative to the control culture without the sodium benzoate. The final xylitol concentration and the average xylitol yield on xylose were nearly 50gL(-1) and 0.57gg(-1), respectively, in the presence of sodium benzoate. Both these values were substantially higher than reported for the same fermentation under microaerobic conditions. Therefore, a fed-batch aerobic fermentation in the presence of sodium benzoate is promising for xylitol production using C. mogii. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Modelling and properties of a nonlinear autonomous switching system in fed-batch culture of glycerol

    Science.gov (United States)

    Wang, Juan; Sun, Qingying; Feng, Enmin

    2012-11-01

    A nonlinear autonomous switching system is proposed to describe the coupled fed-batch fermentation with the pH as the feedback parameter. We prove the non-Zeno behaviors of the switching system and some basic properties of its solution, including the existence, uniqueness, boundedness and regularity. Numerical simulation is also carried out, which reveals that the proposed system can describe the factual fermentation process properly.

  10. Microbial lipid production by oleaginous yeast Cryptococcus sp. in the batch cultures using corncob hydrolysate as carbon source

    International Nuclear Information System (INIS)

    Chang, Yi-Huang; Chang, Ku-Shang; Lee, Ching-Fu; Hsu, Chuan-Liang; Huang, Cheng-Wei; Jang, Hung-Der

    2015-01-01

    To realize the feasibility of biodiesel production from high-lipid cell culture, microbial lipid production by the oleaginous yeasts was studied using glucose and sucrose as carbon source. Among the tested strains, Cryptococcus sp. SM5S05 accumulated the highest levels of intracellular lipids. The crude lipid contents of Cryptococcus sp. cultured in yeast malt agar reached 30% on a dry weight basis. The accumulation of lipids strongly depended on carbon/nitrogen ratio and nitrogen concentration. The highest content of lipids, measured at a carbon/nitrogen ratio of 60–90 and at a nitrogen concentration of 0.2%, was 60–57% lipids in the dry biomass. Batch cultures using corncob hydrolysate demonstrated that there was minimal inhibitory effect with a reducing sugar concentration of 60 g l −1 or higher. Batch cultures of Cryptococcus sp. SM5S05 in the corncob hydrolysate medium with 60 g l −1 glucose resulted in a dry biomass, lipid yields, and content of 12.6 g l −1 , 7.6 g l −1 , and 60.2%, respectively. The lipids contained mainly long-chain saturated and unsaturated fatty acids with 16 and 18 carbon atoms. The fatty acid profile of Cryptococcus oils was quite similar to that of conventional vegetable oil. The cost of lipid production could be further reduced with corncob hydrolysate being utilized as the raw material for the oleaginous yeast. The results showed that the microbial lipid from Cryptococcus sp. was a potential alternative resource for biodiesel production. - Highlights: • Microbial oil production from oleaginous yeast Cryptococcus sp. was studied. • Accumulation of lipid strongly depended on C/N ratio and nitrogen concentration. • Cultures in hydrolysate medium with 60 g/l glucose resulted in maximum lipid yields. • Maximal lipid content in the Cryptococcus sp. were 60.2% on dried weight basis

  11. A multi-pronged investigation into the effect of glucose starvation and culture duration on fed-batch CHO cell culture

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian

    2015-01-01

    to the interplay between the dilution effect associated with change in specific productivity of mAbs and the changed nucleotide sugar metabolism. Herein, we also show and discuss that increased cell culture duration negatively affect the maturation of glycans. In addition, comparative proteomics analysis of cells......In this study, omics-based analysis tools were used to explore the effect of glucose starvation and culture duration on monoclonal antibody (mAb) production in fed-batch CHO cell culture to gain better insight into how these parameters can be controlled to ensure optimal mAb productivity...... and quality. Titer and N-glycosylation of mAbs, as well as proteomic signature and metabolic status of the production cells in the culture were assessed. We found that the impact of glucose starvation on the titer and N-glycosylation of mAbs was dependent on the degree of starvation during early stationary...

  12. COMPARISON OF VACUUM AND HIGH PRESSURE EVAPORATED WOOD HYDROLYZATE FOR ETHANOL PRODUCTION BY REPEATED FED-BATCH USING FLOCCULATING SACCHAROMYCES CEREVISIAE

    Directory of Open Access Journals (Sweden)

    Anahita Dehkhoda

    2009-02-01

    Full Text Available With the aim of increasing the sugars concentration in dilute-acid ligno-cellulosic hydrolyzate to more than 100 g/l for industrial applications, the hydrolyzate from spruce was concentrated about threefold by high-pressure or vacuum evaporations. It was then fermented by repeated fed-batch cultivation using flocculating Saccharomyces cerevisiae with no prior detoxification. The sugars and inhibitors concentrations in the hydrolyzates were compared after the evaporations and also fermenta-tion. The evaporations were carried out either under vacuum (VEH at 0.5 bar and 80°C or with 1.3 bar pressure (HPEH at 107.5°C, which resulted in 153.3 and 164.6 g/l total sugars, respectively. No sugar decomposition occurred during either of the evaporations, while more than 96% of furfural and to a lesser extent formic and acetic acids disappeared from the hydrolyzates. However, HMF and levulinic acid remained in the hydrolyzates and were concentrated proportionally. The concentrated hydrolyzates were then fermented in a 4 l bioreactor with 12-22 g/l yeast and 0.14-0.22 h-1 initial dilute rates (ID. More than 84% of the fermentable sugars present in the VEH were fermented by fed-batch cultivation using 12 g/l yeast and initial dilution rate (ID of 0.22 h-1, and resulted in 0.40±0.01 g/g ethanol from the fermentable sugars in one cycle of fermentation. Fermentation of HPEH was as successful as VEH and resulted in more than 86% of the sugar consumption under the corresponding conditions. By lowering the initial dilution rate to 0.14 h-1, more than 97% of the total fermentable sugars were consumed, and ethanol yield was 0.44±0.01 g/g in one cycle of fermentation. The yeast was able to convert or assimilate HMF, levulinic, acetic, and formic acids by 96, 30, 43, and 74%, respectively.

  13. In Vitro Growth of Curcuma longa L. in Response to Five Mineral Elements and Plant Density in Fed-Batch Culture Systems

    Science.gov (United States)

    El-Hawaz, Rabia F.; Bridges, William C.; Adelberg, Jeffrey W.

    2015-01-01

    Plant density was varied with P, Ca, Mg, and KNO3 in a multifactor experiment to improve Curcuma longa L. micropropagation, biomass and microrhizome development in fed-batch liquid culture. The experiment had two paired D-optimal designs, testing sucrose fed-batch and nutrient sucrose fed-batch techniques. When sucrose became depleted, volume was restored to 5% m/v sucrose in 200 ml of modified liquid MS medium by adding sucrose solutions. Similarly, nutrient sucrose fed-batch was restored to set points with double concentration of treatments’ macronutrient and MS micronutrient solutions, along with sucrose solutions. Changes in the amounts of water and sucrose supplementations were driven by the interaction of P and KNO3 concentrations. Increasing P from 1.25 to 6.25 mM increased both multiplication and biomass. The multiplication ratio was greatest in the nutrient sucrose fed-batch technique with the highest level of P, 6 buds/vessel, and the lowest level of Ca and KNO3. The highest density (18 buds/vessel) produced the highest fresh biomass at the highest concentrations of KNO3 and P with nutrient sucrose fed-batch, and moderate Ca and Mg concentrations. However, maximal rhizome dry biomass required highest P, sucrose fed-batch, and a moderate plant density. Different media formulations and fed-batch techniques were identified to maximize the propagation and storage organ responses. A single experimental design was used to optimize these dual purposes. PMID:25830292

  14. In vitro growth of Curcuma longa L. in response to five mineral elements and plant density in fed-batch culture systems.

    Science.gov (United States)

    El-Hawaz, Rabia F; Bridges, William C; Adelberg, Jeffrey W

    2015-01-01

    Plant density was varied with P, Ca, Mg, and KNO3 in a multifactor experiment to improve Curcuma longa L. micropropagation, biomass and microrhizome development in fed-batch liquid culture. The experiment had two paired D-optimal designs, testing sucrose fed-batch and nutrient sucrose fed-batch techniques. When sucrose became depleted, volume was restored to 5% m/v sucrose in 200 ml of modified liquid MS medium by adding sucrose solutions. Similarly, nutrient sucrose fed-batch was restored to set points with double concentration of treatments' macronutrient and MS micronutrient solutions, along with sucrose solutions. Changes in the amounts of water and sucrose supplementations were driven by the interaction of P and KNO3 concentrations. Increasing P from 1.25 to 6.25 mM increased both multiplication and biomass. The multiplication ratio was greatest in the nutrient sucrose fed-batch technique with the highest level of P, 6 buds/vessel, and the lowest level of Ca and KNO3. The highest density (18 buds/vessel) produced the highest fresh biomass at the highest concentrations of KNO3 and P with nutrient sucrose fed-batch, and moderate Ca and Mg concentrations. However, maximal rhizome dry biomass required highest P, sucrose fed-batch, and a moderate plant density. Different media formulations and fed-batch techniques were identified to maximize the propagation and storage organ responses. A single experimental design was used to optimize these dual purposes.

  15. Kinetics of sugars consumption and ethanol inhibition in carob pulp fermentation by Saccharomyces cerevisiae in batch and fed-batch cultures.

    Science.gov (United States)

    Lima-Costa, Maria Emília; Tavares, Catarina; Raposo, Sara; Rodrigues, Brígida; Peinado, José M

    2012-05-01

    The waste materials from the carob processing industry are a potential resource for second-generation bioethanol production. These by-products are small carob kibbles with a high content of soluble sugars (45-50%). Batch and fed-batch Saccharomyces cerevisiae fermentations of high density sugar from carob pods were analyzed in terms of the kinetics of sugars consumption and ethanol inhibition. In all the batch runs, 90-95% of the total sugar was consumed and transformed into ethanol with a yield close to the theoretical maximum (0.47-0.50 g/g), and a final ethanol concentration of 100-110 g/l. In fed-batch runs, fresh carob extract was added when glucose had been consumed. This addition and the subsequent decrease of ethanol concentrations by dilution increased the final ethanol production up to 130 g/l. It seems that invertase activity and yeast tolerance to ethanol are the main factors to be controlled in carob fermentations. The efficiency of highly concentrated carob fermentation makes it a very promising process for use in a second-generation ethanol biorefinery.

  16. Efficacy of a commercial probiotic relative to oxytetracycline as Gram-negative bacterial control agents in a rotifer (Brachionus plicatilis) batch culture

    Science.gov (United States)

    Two trials were conducted to evaluate two gram-negative bacterial control strategies in batch cultures of the rotifer Brachionus plicatilis. In the first trial, rotifers at an initial density of 47/mL were cultured for 5 d and dosed with a 10-mg/L solution of either oxytetracycline or a commercial p...

  17. Dynamic flux balance modeling of microbial co-cultures for efficient batch fermentation of glucose and xylose mixtures.

    Science.gov (United States)

    Hanly, Timothy J; Henson, Michael A

    2011-02-01

    Sequential uptake of pentose and hexose sugars that compose lignocellulosic biomass limits the ability of pure microbial cultures to efficiently produce value-added bioproducts. In this work, we used dynamic flux balance modeling to examine the capability of mixed cultures of substrate-selective microbes to improve the utilization of glucose/xylose mixtures and to convert these mixed substrates into products. Co-culture simulations of Escherichia coli strains ALS1008 and ZSC113, engineered for glucose and xylose only uptake respectively, indicated that improvements in batch substrate consumption observed in previous experimental studies resulted primarily from an increase in ZSC113 xylose uptake relative to wild-type E. coli. The E. coli strain ZSC113 engineered for the elimination of glucose uptake was computationally co-cultured with wild-type Saccharomyces cerevisiae, which can only metabolize glucose, to determine if the co-culture was capable of enhanced ethanol production compared to pure cultures of wild-type E. coli and the S. cerevisiae strain RWB218 engineered for combined glucose and xylose uptake. Under the simplifying assumption that both microbes grow optimally under common environmental conditions, optimization of the strain inoculum and the aerobic to anaerobic switching time produced an almost twofold increase in ethanol productivity over the pure cultures. To examine the effect of reduced strain growth rates at non-optimal pH and temperature values, a break even analysis was performed to determine possible reductions in individual strain substrate uptake rates that resulted in the same predicted ethanol productivity as the best pure culture. © 2010 Wiley Periodicals, Inc.

  18. Advanced control of dissolved oxygen concentration in fed batch cultures during recombinant protein production.

    Science.gov (United States)

    Kuprijanov, A; Gnoth, S; Simutis, R; Lübbert, A

    2009-02-01

    Design and experimental validation of advanced pO(2) controllers for fermentation processes operated in the fed-batch mode are described. In most situations, the presented controllers are able to keep the pO(2) in fermentations for recombinant protein productions exactly on the desired value. The controllers are based on the gain-scheduling approach to parameter-adaptive proportional-integral controllers. In order to cope with the most often appearing distortions, the basic gain-scheduling feedback controller was complemented with a feedforward control component. This feedforward/feedback controller significantly improved pO(2) control. By means of numerical simulations, the controller behavior was tested and its parameters were determined. Validation runs were performed with three Escherichia coli strains producing different recombinant proteins. It is finally shown that the new controller leads to significant improvements in the signal-to-noise ratio of other key process variables and, thus, to a higher process quality.

  19. Development of a chemically defined platform fed-batch culture media for monoclonal antibody-producing CHO cell lines with optimized choline content.

    Science.gov (United States)

    Kuwae, Shinobu; Miyakawa, Ichiko; Doi, Tomohiro

    2018-01-11

    A chemically defined platform basal medium and feed media were developed using a single Chinese hamster ovary (CHO) cell line that produces a monoclonal antibody (mAb). Cell line A, which showed a peak viable cell density of 5.9 × 10 6  cells/mL and a final mAb titer of 0.5 g/L in batch culture, was selected for the platform media development. Stoichiometrically balanced feed media were developed using glucose as an indicator of cell metabolism to determine the feed rates of all other nutrients. A fed-batch culture of cell line A using the platform fed-batch medium yielded a 6.4 g/L mAb titer, which was 12-fold higher than that of the batch culture. To examine the applicability of the platform basal medium and feed media, three other cell lines (A16, B, and C) that produce mAbs were cultured using the platform fed-batch medium, and they yielded mAb titers of 8.4, 3.3, and 6.2 g/L, respectively. The peak viable cell densities of the three cell lines ranged from 1.3 × 10 7 to 1.8 × 10 7  cells/mL. These results show that the nutritionally balanced fed-batch medium and feeds worked well for other cell lines. During the medium development, we found that choline limitation caused a lower cell viability, a lower mAb titer, a higher mAb aggregate content, and a higher mannose-5 content. The optimal choline chloride to glucose ratio for the CHO cell fed-batch culture was determined. Our platform basal medium and feed media will shorten the medium-development time for mAb-producing cell lines.

  20. Multivariate statistical process control (MSPC) using Raman spectroscopy for in-line culture cell monitoring considering time-varying batches synchronized with correlation optimized warping (COW).

    Science.gov (United States)

    Liu, Ya-Juan; André, Silvère; Saint Cristau, Lydia; Lagresle, Sylvain; Hannas, Zahia; Calvosa, Éric; Devos, Olivier; Duponchel, Ludovic

    2017-02-01

    Multivariate statistical process control (MSPC) is increasingly popular as the challenge provided by large multivariate datasets from analytical instruments such as Raman spectroscopy for the monitoring of complex cell cultures in the biopharmaceutical industry. However, Raman spectroscopy for in-line monitoring often produces unsynchronized data sets, resulting in time-varying batches. Moreover, unsynchronized data sets are common for cell culture monitoring because spectroscopic measurements are generally recorded in an alternate way, with more than one optical probe parallelly connecting to the same spectrometer. Synchronized batches are prerequisite for the application of multivariate analysis such as multi-way principal component analysis (MPCA) for the MSPC monitoring. Correlation optimized warping (COW) is a popular method for data alignment with satisfactory performance; however, it has never been applied to synchronize acquisition time of spectroscopic datasets in MSPC application before. In this paper we propose, for the first time, to use the method of COW to synchronize batches with varying durations analyzed with Raman spectroscopy. In a second step, we developed MPCA models at different time intervals based on the normal operation condition (NOC) batches synchronized by COW. New batches are finally projected considering the corresponding MPCA model. We monitored the evolution of the batches using two multivariate control charts based on Hotelling's T 2 and Q. As illustrated with results, the MSPC model was able to identify abnormal operation condition including contaminated batches which is of prime importance in cell culture monitoring We proved that Raman-based MSPC monitoring can be used to diagnose batches deviating from the normal condition, with higher efficacy than traditional diagnosis, which would save time and money in the biopharmaceutical industry. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Production of Medium Chain Length Polyhydroxyalkanoates From Oleic Acid Using Pseudomonas putida PGA1 by Fed Batch Culture

    Directory of Open Access Journals (Sweden)

    Sidik Marsudi

    2010-10-01

    Full Text Available Bacterial polyhydroxyalkanoates (PHAs are a class of p0lymers currently receiving much attention because of their potential as renewable and biodegradable plastics. A wide variety of bacteria has been reported to produce PHAs including Pseudomonas strains. These strains are known as versatile medium chain length PHAs (PHAs-mcl producers using fatty acids as carbon source. Oleic acid was used to produce PHAs-mcl using Pseudomonas putida PGA 1 by continuous feeding of both nitrogen and carbon source, in a fed batch culture. During cell growth, PHAs also accumulated, indicating that PHA production in this organism is growth associated. Residual cell increased until the nitrogen source was depleted. At the end of fermentation, final cell concentration, PHA content, and roductivity were 30.2 g/L, 44.8 % of cell dry weight, and 0.188 g/l/h, respectively.

  2. Acquisition of data from on-line laser turbidimeter and calculation of some kinetic variables in computer-coupled automated fed-batch culture

    International Nuclear Information System (INIS)

    Kadotani, Y.; Miyamoto, K.; Mishima, N.; Kominami, M.; Yamane, T.

    1995-01-01

    Output signals of a commercially available on-line laser turbidimeter exhibit fluctuations due to air and/or CO 2 bubbles. A simple data processing algorithm and a personal computer software have been developed to smooth the noisy turbidity data acquired, and to utilize them for the on-line calculations of some kinetic variables involved in batch and fed-batch cultures of uniformly dispersed microorganisms. With this software, about 10 3 instantaneous turbidity data acquired over 55 s are averaged and convert it to dry cell concentration, X, every minute. Also, volume of the culture broth, V, is estimated from the averaged output data of weight loss of feed solution reservoir, W, using an electronic balance on which the reservoir is placed. Then, the computer software is used to perform linear regression analyses over the past 30 min of the total biomass, VX, the natural logarithm of the total biomass, ln(VX), and the weight loss, W, in order to calculate volumetric growth rate, d(VX)/dt, specific growth rate, μ [ = dln(VX)/dt] and the rate of W, dW/dt, every minute in a fed-batch culture. The software used to perform the first-order regression analyses of VX, ln(VX) and W was applied to batch or fed-batch cultures of Escherichia coli on minimum synthetic or natural complex media. Sample determination coefficients of the three different variables (VX, ln(VX) and W) were close to unity, indicating that the calculations are accurate. Furthermore, growth yield, Y x/s , and specific substrate consumption rate, q sc , were approximately estimated from the data, dW/dt and in a ‘balanced’ fed-batch culture of E. coli on the minimum synthetic medium where the computer-aided substrate-feeding system automatically matches well with the cell growth. (author)

  3. LIPID PRODUCTION BY DUNALIELLA SALINA IN BATCH CULTURE: EFFECTS OF NITROGEN LIMITATION AND LIGHT INTENSITY

    Energy Technology Data Exchange (ETDEWEB)

    Weldy, C.S.; Huesemann, M.

    2007-01-01

    Atmospheric carbon dioxide (CO2) concentrations are increasing and may cause unknown deleterious environmental effects if left unchecked. The Intergovernmental Panel on Climate Change (IPCC) has predicted in its latest report a 2°C to 4°C increase in global temperatures even with the strictest CO2 mitigation practices. Global warming can be attributed in large part to the burning of carbon-based fossil fuels, as the concentration of atmospheric CO2 is directly related to the burning of fossil fuels. Biofuels which do not add CO2 to the atmosphere are presently generated primarily from terrestrial plants, i.e., ethanol from corn grain and biodiesel from soybean oil. The production of biofuels from terrestrial plants is severely limited by the availability of fertile land. Lipid production from microalgae and its corresponding biodiesel production have been studied since the late 1970s but large scale production has remained economically infeasible due to the large costs of sterile growing conditions required for many algal species. This study focuses on the potential of the halophilic microalgae species Dunaliella salina as a source of lipids and subsequent biodiesel production. The lipid production rates under high light and low light as well as nitrogen suffi cient and nitrogen defi cient culture conditions were compared for D. salina cultured in replicate photobioreactors. The results show (a) cellular lipid content ranging from 16 to 44% (wt), (b) a maximum culture lipid concentration of 450mg lipid/L, and (c) a maximum integrated lipid production rate of 46mg lipid/L culture*day. The high amount of lipids produced suggests that D. salina, which can be mass-cultured in non-sterile outdoor ponds, has strong potential to be an economically valuable source for renewable oil and biodiesel production.

  4. ON-LINE MONITORING OF BIOMASS CONCENTRATION BASED ON A CAPACITANCE SENSOR: ASSESSING THE METHODOLOGY FOR DIFFERENT BACTERIA AND YEAST HIGH CELL DENSITY FED-BATCH CULTURES

    Directory of Open Access Journals (Sweden)

    A. C. L. Horta

    2015-12-01

    Full Text Available Abstract The performance of an in-situ capacitance sensor for on-line monitoring of biomass concentration was evaluated for some of the most important microorganisms in the biotechnology industry: Escherichia coli, Saccharomyces cerevisiae, Pichia pastoris and Bacillus megaterium. A total of 33 batch and fed-batch cultures were carried out in a bench-scale bioreactor and biomass formation trends were followed by dielectric measurements during the growth phase as well as the induction phase, for 5 recombinant E. coli strains. Permittivity measurements and viable cellular concentrations presented a linear correlation for all the studied conditions. In addition, the permittivity signal was further used for inference of the cellular growth rate. The estimated specific growth rates mirrored the main trends of the metabolic states of the different cells and they can be further used for setting-up control strategies in fed-batch cultures.

  5. Magnesium Uptake by the Green Microalga Chlorella vulgaris in Batch Cultures.

    Science.gov (United States)

    Ben Amor-Ben Ayed, Hela; Taidi, Behnam; Ayadi, Habib; Pareau, Dominique; Stambouli, Moncef

    2016-03-01

    The accumulation (internal and superficial distribution) of magnesium ions (Mg(2+)) by the green freshwater microalga Chlorella vulgaris (C. vulgaris) was investigated under autotrophic culture in a stirred photobioreactor. The concentrations of the three forms of Mg(2+) (dissolved, extracellular, and intracellular) were determined with atomic absorption spectroscopy during the course of C. vulgaris growth. The proportions of adsorbed (extracellular) and absorbed (intracellular) Mg(2+) were quantified. The concentration of the most important pigment in algal cells, chlorophyll a, increased over time in proportion to the increase in the biomass concentration, indicating a constant chlorophyll/biomass ratio during the linear growth phase. The mean-average rate of Mg(2+) uptake by C. vulgaris grown in a culture medium starting with 16 mg/l of Mg(2+) concentration was measured. A clear relationship between the biomass concentration and the proportion of the Mg(2+) removal from the medium was observed. Of the total Mg(2+) present in the culture medium, 18% was adsorbed on the cell wall and 51% was absorbed by the biomass by the end of the experiment (765 h). Overall, 69% of the initial Mg(2+) were found to be removed from the medium. This study supported the kinetic model based on a reversible first-order reaction for Mg(2+) bioaccumulation in C. vulgaris, which was consistent with the experimental data.

  6. High level expression of Glomerella cingulata cutinase in dense cultures of Pichia pastoris grown under fed-batch conditions.

    Science.gov (United States)

    Seman, W M K Wan; Bakar, S A; Bukhari, N A; Gaspar, S M; Othman, R; Nathan, S; Mahadi, N M; Jahim, J; Murad, A M A; Bakar, F D Abu

    2014-08-20

    A Pichia pastoris transformant carrying the cutinase cDNA of Glomerella cingulata was over-expressed in a 5L bioreactor (2.0L working volume) under fed-batch conditions. Bioreactor experiments rely on varying selected parameters in repeated rounds of optimisation: here these included duration of induction, pH and temperature. Highest cell densities (320gL(-1) wet cell weight) with a cutinase production of 3800mgL(-1) and an activity of 434UmL(-1) were achieved 24h after induction with methanol in basal salt medium (at pH 5 and 28°C). Characterisation of the cutinase showed that it was stable between pH 6 and pH 11, had an optimum pH of 8.0 and retained activity for 30min at 50°C (optimum temperature 25°C).The preferred substrates of G. cingulata cutinase were the medium- to long-chain ρ-nitrophenyl esters of ρ-nitrophenylcaprylate (C8), ρ-nitrophenyllaurate (C12) and ρ-nitrophenylmyristate (C14), with the highest catalytic efficiency, kcat/Km of 7.7±0.7mM(-1)s(-1) for ρ-nitrophenylcaprylate. Microscopic analyses showed that the G. cingulata cutinase was also capable of depolymerising the high molecular weight synthetic polyester, polyethylene terephthalate. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. [Optimization of cultural condition of genetic engineering strain for antibiotic peptide adenoregulin and research on its fed-batch cultivation].

    Science.gov (United States)

    Zhou, Yu-Xun; Cao, Wei; Wei, Dong-Zhi; Luo, Qing-Ping; Wang, Jin-Zhi

    2005-07-01

    33 amino acid antibiotic peptide adenoregulin (ADR), which were firstly isolated from the skin of South America arboreal frog Phyllomedusa bicolor, forms alpha-helix amphipathic structure in apolar medium and has a wide spectrum of antimicrobial activity and high potency of lytic ability. Adr gene was cloned in pET32a and transformed into Escherichia coli BL21(DE3) . The cultural and inductive conditions of E. coli BL21(DE3)/pET32a-adr have been optimized. The effect of three factors which were time point of induction, concentration of IPTG in the culture and time of induction on the expression level of Trx-ADR was investigated. The results indicated that the expression level was affected by the time point of induction most predominantly. 9 veriaties of media in which BL21 (DE3)/pET32a-adr was cultured and induced were tested to achieve high expression level of target protein. It was found that glucose in the medium played an important role in keeping stable and high expression level of Trx-ADR. The optimal inductive condition is as follows: the culture medium is 2 x YT + 0.5% glucose, the time point of induction is OD600 = 0.9, the final concentration of IPTG in the culture is 0.1 mmol/L and the induction time is 4 h. BL21 (DE3)/pET32a-adr was cultivated according to the strategy of constant pH at early stage and exponential feeding at later stage to obtain high cell density. During the entire fed-batch phase, by controlling the feeding of glucose, the specific growth rate of the culture was controlled at about 0.15 h(-1), the accumulation of acetic acid was controlled at low level (<2 g/L), but the plasmid stability could not be maintained well. At the end of the cultivation, 40% of the bacteria in the culture lost their plasmids. As a result, the expression level of the target protein declined dramatically, but 90% of Trx-ADR was in soluble form. The expressed fusion protein showed no antibacterial activity, while the native form of ADR lysed from Trx-ADR showed

  8. CHANGES IN CHLOROPHYLL A FLOURESCENCE AND PIGMENT RATIOS DURING DIFFERENT GROWTH PHASES OF A UNICELLULAR MARINE CHAETOCEROS (BACILLAROPHYCEAE) IN BATCH CULTURE

    Science.gov (United States)

    Interpretations of chlorophyll a fluorescence data are based largely on application with green algae and higher plants. This study evaluated the interpretation of fluorescence data for a unicellular marine diatom. Chaetoceros sp. was grown in 4-liter batch cultures on a 16:8, L:D...

  9. Production of functional killer protein in batch cultures upon a shift from aerobic to anaerobic conditions

    Directory of Open Access Journals (Sweden)

    Gildo Almeida da Silva

    2011-06-01

    Full Text Available The aim of this work was to study the production of functional protein in yeast culture. The cells of Saccharomyces cerevisiae Embrapa 1B (K+R+ killed a strain of Saccharomyces cerevisiae Embrapa 26B (K-R-in grape must and YEPD media. The lethal effect of toxin-containing supernatant and the effect of aeration upon functional killer production and the correlation between the products of anaerobic metabolism and the functional toxin formation were evaluated. The results showed that at low sugar concentration, the toxin of the killer strain of Sacch. cerevisiae was only produced under anaerobic conditions . The system of killer protein production showed to be regulated by Pasteur and Crabtree effects. As soon as the ethanol was formed, the functional killer toxin was produced. The synthesis of the active killer toxin seemed to be somewhat associated with the switch to fermentation process and with concomitant alcohol dehydrogenase (ADH activity.

  10. Hepatitis B surface antigen (HBsAg) expression in plant cell culture: Kinetics of antigen accumulation in batch culture and its intracellular form.

    Science.gov (United States)

    Smith, Mark L; Mason, Hugh S; Shuler, Michael L

    2002-12-30

    The production of edible vaccines in transgenic plants and plant cell culture may be improved through a better understanding of antigen processing and assembly. The hepatitis B surface antigen (HBsAg) was chosen for study because it undergoes substantial and complex post-translational modifications, which are necessary for its immunogenicity. This antigen was expressed in soybean (Glycine max L. Merr. cv Williams 82) and tobacco NT1 (Nicotiana tabacum L.) cell suspension cultures, and HBsAg production in batch culture was characterized. The plant-derived antigen consisted predominantly of disulfide cross-linked HBsAg protein (p24(s)) dimers, which were all membrane associated. Similar to yeast, the plant-expressed HBsAg was retained intracellularly. The maximal HBsAg titers were obtained with soybean suspension cultures (20-22 mg/L) with titers in tobacco cultures being approximately 10-fold lower. For soybean cells, electron microscopy and immunolocalization demonstrated that all the HBsAg was localized to the endoplasmic reticulum (ER) and provoked dilation and proliferation of the ER network. Sucrose gradient analysis of crude extracts showed that HBsAg had a complex size distribution uncharacteristic of the antigen's normal structure of uniform 22-nm virus-like particles. The extent of authentic epitope formation was assessed by comparing total p24(s) synthesized to that reactive by polyclonal and monoclonal immunoassays. Depending on culture age, between 40% and 100% of total p24(s) was polyclonal antibody reactive whereas between 6% and 37% was recognized by a commercial monoclonal antibody assay. Possible strategies to increase HBsAg production and improve post-translational processing are discussed. Copyright 2002 Wiley Periodicals, Inc.

  11. The "saying is repeating" effect: dyadic communication can generate cultural stereotypes.

    Science.gov (United States)

    Bratanova, Boyka; Kashima, Yoshi

    2014-01-01

    It has been long established that interpersonal communication underpins the existence of cultural stereotypes. However, research has either examined the formation of new or the maintenance of existing stereotypes. In a series of three studies, the present research bridges the gap between these phases by showing that newly formed stereotypes can spread through repeated dyadic communication with others. The stereotypic representation arose due to the audience tuning in to communication to a first audience. Further transmission to two types of subsequent audiences was simulated: a newcomer and an old-timer with an unknown attitude towards the target. A "saying-is-repeating" effect was obtained: the stereotypic representation was invariably transmitted to the newcomer, regardless of whether communicators personally believed in the bias; perceived group-level consensus moderated its transmission to the old-timer. These findings demonstrate that once a stereotypic representation is formed, it is likely to spread in a community and potentially become a cultural stereotype.

  12. Calcium transcriptionally regulates the biofilm machinery of Xylella fastidiosa to promote continued biofilm development in batch cultures.

    Science.gov (United States)

    Parker, Jennifer K; Chen, Hongyu; McCarty, Sara E; Liu, Lawrence Y; De La Fuente, Leonardo

    2016-05-01

    The functions of calcium (Ca) in bacteria are less characterized than in eukaryotes, where its role has been studied extensively. The plant-pathogenic bacterium Xylella fastidiosa has several virulence features that are enhanced by increased Ca concentrations, including biofilm formation. However, the specific mechanisms driving modulation of this feature are unclear. Characterization of biofilm formation over time showed that 4 mM Ca supplementation produced denser biofilms that were still developing at 96 h, while biofilm in non-supplemented media had reached the dispersal stage by 72 h. To identify changes in global gene expression in X. fastidiosa grown in supplemental Ca, RNA-Seq of batch culture biofilm cells was conducted at three 24-h time intervals. Results indicate that a variety of genes are differentially expressed in response to Ca, including genes related to attachment, motility, exopolysaccharide synthesis, biofilm formation, peptidoglycan synthesis, regulatory functions, iron homeostasis, and phages. Collectively, results demonstrate that Ca supplementation induces a transcriptional response that promotes continued biofilm development, while biofilm cells in nonsupplemented media are driven towards dispersion of cells from the biofilm structure. These results have important implications for disease progression in planta, where xylem sap is the source of Ca and other nutrients for X. fastidiosa. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  13. Genetic Algorithmic Optimization of PHB Production by a Mixed Culture in an Optimally Dispersed Fed-batch Bioreactor

    Directory of Open Access Journals (Sweden)

    Pratap R. Patnaik

    2009-10-01

    Full Text Available Poly-β-hydroxybutyrate (PHB is an energy-storage polymer whose properties are similar to those of chemical polymers such as polyethylene and polypropylene. Moreover, PHB is biodegradable, absorbed by human tissues and less energy-consuming than synthetic polymers. Although Ralstonia eutropha is widely used to synthesize PHB, it is inefficient in utilizing glucose and similar sugars. Therefore a co-culture of R. eutropha and Lactobacillus delbrueckii is preferred since the latter can convert glucose to lactate, which R. eutropha can metabolize easily. Tohyama et al. [24] maximized PHB production in a well-mixed fed-batch bioreactor with glucose and (NH42SO4 as the primary substrates. Since production-scale bioreactors often deviate from ideal laboratory-scale reactors, a large bioreactor was simulated by means of a dispersion model with the kinetics determined by Tohyama et al. [24] and dispersion set at an optimum Peclet number of 20 [32]. The time-dependent feed rates of the two substrates were determined through a genetic algorithm (GA to maximize PHB production. This bioreactor produced 22.2% more PHB per liter and 12.8% more cell mass than achieved by Tohyama et al. [24]. These results, and similar observations with other fermentations, indicate the feasibility of enhancing the efficiency of large nonideal bioreactors through GA optimizations.

  14. In vitro rumen feed degradability assessed with DaisyII and batch culture: effect of sample size

    Directory of Open Access Journals (Sweden)

    Stefano Schiavon

    2010-01-01

    Full Text Available In vitro degradability with DaisyII (D equipment is commonly performed with 0.5g of feed sample into each filter bag. Literature reported that a reduction of the ratio of sample size to bag surface could facilitate the release of soluble or fine particulate. A reduction of sample size to 0.25 g could improve the correlation between the measurements provided by D and the conventional batch culture (BC. This hypothesis was screened by analysing the results of 2 trials. In trial 1, 7 feeds were incubated for 48h with rumen fluid (3 runs x 4 replications both with D (0.5g/bag and BC; the regressions between the mean values provided for the various feeds in each run by the 2 methods either for NDF (NDFd and in vitro true DM (IVTDMD degradability, had R2 of 0.75 and 0.92 and RSD of 10.9 and 4.8%, respectively. In trial 2, 4 feeds were incubated (2 runs x 8 replications with D (0.25 g/bag and BC; the corresponding regressions for NDFd and IVTDMD showed R2 of 0.94 and 0.98 and RSD of 3.0 and 1.3%, respectively. A sample size of 0.25 g improved the precision of the measurements obtained with D.

  15. Combined data preprocessing and multivariate statistical analysis characterizes fed-batch culture of mouse hybridoma cells for rational medium design.

    Science.gov (United States)

    Selvarasu, Suresh; Kim, Do Yun; Karimi, Iftekhar A; Lee, Dong-Yup

    2010-10-01

    We present an integrated framework for characterizing fed-batch cultures of mouse hybridoma cells producing monoclonal antibody (mAb). This framework systematically combines data preprocessing, elemental balancing and statistical analysis technique. Initially, specific rates of cell growth, glucose/amino acid consumptions and mAb/metabolite productions were calculated via curve fitting using logistic equations, with subsequent elemental balancing of the preprocessed data indicating the presence of experimental measurement errors. Multivariate statistical analysis was then employed to understand physiological characteristics of the cellular system. The results from principal component analysis (PCA) revealed three major clusters of amino acids with similar trends in their consumption profiles: (i) arginine, threonine and serine, (ii) glycine, tyrosine, phenylalanine, methionine, histidine and asparagine, and (iii) lysine, valine and isoleucine. Further analysis using partial least square (PLS) regression identified key amino acids which were positively or negatively correlated with the cell growth, mAb production and the generation of lactate and ammonia. Based on these results, the optimal concentrations of key amino acids in the feed medium can be inferred, potentially leading to an increase in cell viability and productivity, as well as a decrease in toxic waste production. The study demonstrated how the current methodological framework using multivariate statistical analysis techniques can serve as a potential tool for deriving rational medium design strategies. Copyright © 2010 Elsevier B.V. All rights reserved.

  16. Metabolic Control in Mammalian Fed-Batch Cell Cultures for Reduced Lactic Acid Accumulation and Improved Process Robustness

    Directory of Open Access Journals (Sweden)

    Viktor Konakovsky

    2016-01-01

    Full Text Available Biomass and cell-specific metabolic rates usually change dynamically over time, making the “feed according to need” strategy difficult to realize in a commercial fed-batch process. We here demonstrate a novel feeding strategy which is designed to hold a particular metabolic state in a fed-batch process by adaptive feeding in real time. The feed rate is calculated with a transferable biomass model based on capacitance, which changes the nutrient flow stoichiometrically in real time. A limited glucose environment was used to confine the cell in a particular metabolic state. In order to cope with uncertainty, two strategies were tested to change the adaptive feed rate and prevent starvation while in limitation: (i inline pH and online glucose concentration measurement or (ii inline pH alone, which was shown to be sufficient for the problem statement. In this contribution, we achieved metabolic control within a defined target range. The direct benefit was two-fold: the lactic acid profile was improved and pH could be kept stable. Multivariate Data Analysis (MVDA has shown that pH influenced lactic acid production or consumption in historical data sets. We demonstrate that a low pH (around 6.8 is not required for our strategy, as glucose availability is already limiting the flux. On the contrary, we boosted glycolytic flux in glucose limitation by setting the pH to 7.4. This new approach led to a yield of lactic acid/glucose (Y L/G around zero for the whole process time and high titers in our labs. We hypothesize that a higher carbon flux, resulting from a higher pH, may lead to more cells which produce more product. The relevance of this work aims at feeding mammalian cell cultures safely in limitation with a desired metabolic flux range. This resulted in extremely stable, low glucose levels, very robust pH profiles without acid/base interventions and a metabolic state in which lactic acid was consumed instead of being produced from day 1. With

  17. The improvement of the quality of polluted irrigation water through a phytoremediation process in a hydroponic batch culture system

    Science.gov (United States)

    Retnaningdyah, Catur

    2017-11-01

    The objective of this research was to determine the effectiveness of a phytoremediation process using some local hydro macrophytes to reduce fertilizer residue in irrigation water in order to support healthy agriculture and to prevent eutrophication and algae bloom in water. A phytoremediation process was carried out in a hydroponic floating system by using transparent plastic bags of 1 m in diameter and 1 m in height that were placed in collecting ponds before they were used for agricultural activities. Paddy soils were used as substrates in this system. The irrigation water was treated with nutrient enrichment (Urea and SP-36 fertilizers). Then, the system was planted with remediation actors (Azolla sp., Ipomoea aquatica, Limnocharis flava, Marsilea crenata, polyculture of those hydro macrophytes and control). The improvement of the water quality as a result of the phytoremediation process was characterized by a decline in the concentration of some physicochemical parameters, which were measured at 7 days after incubation, as well as an increase in the plankton diversity index value. The results showed that all of the hydro macrophytes used in this research, which was grown in the hydroponic batch culture system for a period of 7 days, were able to significantly improve the irrigation water quality, which was enriched by the synthetic fertilizers Urea and SP36. This was reflected by a significant decrease in the concentration of water TSS, nitrate, BOD, COD and total phosphate and an increase in the value of water DO at 7 days after incubation. Improvement of the water quality is also reflected in the increasing plankton diversity index value as a bioindicator of water pollution indicating a change in the pollution status from moderately polluted to slightly polluted at 7 days after incubation.

  18. Improved productivity of poly (3-hydroxybutyrate) (PHB) in thermophilic Chelatococcus daeguensis TAD1 using glycerol as the growth substrate in a fed-batch culture.

    Science.gov (United States)

    Cui, Bin; Huang, Shaobin; Xu, Fuqian; Zhang, Ruijian; Zhang, Yongqing

    2015-07-01

    A particularly successful polyhydroxyalkanoate (PHA) in industrial applications is poly (3-hydroxybutyrate) (PHB). However, one of the major obstacles for wider application of PHB is the cost of its production and purification. Therefore, it is desirable to discover a method for producing PHB in large quantities at a competitive price. Glycerol is a cheap and widely used carbon source that can be applied in PHB production process. There are numerous advantages to operating fermentation at elevated temperatures; only several thermophilic bacteria are able to accumulate PHB when glycerol is the growth substrate. Here, we report on the possibility of increasing PHB production at low cost using thermophilic Chelatococcus daeguensis TAD1 when glycerol is the growth substrate in a fed-batch culture. We found that (1) excess glycerol inhibited PHB accumulation and (2) organic nitrogen sources, such as tryptone and yeast extract, promoted the growth of C. daeguensis TAD1. In the batch fermentation experiments, we found that using glycerol at low concentrations as the sole carbon source, along with the addition of mixed nitrate (NH4Cl, tryptone, and yeast extract), stimulated PHB accumulation in C. daeguensis TAD1. The results showed that the PHB productivity decreased in the following order: two-stage fed-batch fermentation > fed-batch fermentation > batch fermentation. In optimized culture conditions, a PHB amount of 17.4 g l(-1) was obtained using a two-stage feeding regimen, leading to a productivity rate of 0.434 g l(-1) h(-1), which is the highest productivity rate reported for PHB to date. This high PHB biosynthetic productivity could decrease the total production cost, allowing for further development of industrial applications of PHB.

  19. Determination of some significant batch culture conditions affecting acetyl-xylan esterase production by Penicillium notatum NRRL-1249

    Directory of Open Access Journals (Sweden)

    Akhtar MN

    2011-05-01

    Full Text Available Abstract Background Acetyl-xylan esterase (AXE, EC 3.1.1.72 hydrolyses acetate group from the linear chain of xylopyranose residues bound by β-1,4-linkage. The enzyme finds commercial applications in bio-bleaching of wood pulp, treating animal feed to increase digestibility, processing food to increase clarification and converting lignocellulosics to feedstock and fuel. In the present study, we report on the production of an extracellular AXE from Penicillium notatum NRRL-1249 by solid state fermentation (SSF. Results Wheat bran at a level of 10 g (with 4 cm bed height was optimized as the basal substrate for AXE production. An increase in enzyme activity was observed when 7.5 ml of mineral salt solution (MSS containing 0.1% KH2PO4, 0.05% KCl, 0.05% MgSO4.7H2O, 0.3% NaNO3, 0.001% FeSO4.2H2O and 0.1% (v/w Tween-80 as an initial moisture content was used. Various nitrogen sources including ammonium sulphate, urea, peptone and yeast extract were compared for enzyme production. Maximal enzyme activity of 760 U/g was accomplished which was found to be highly significant (p ≤ 0.05. A noticeable enhancement in enzyme activity was observed when the process parameters including incubation period (48 h, initial pH (5, 0.2% (w/w urea as nitrogen source and 0.5% (v/w Tween-80 as a stimulator were further optimized using a 2-factorial Plackett-Burman design. Conclusion From the results it is clear that an overall improvement of more than 35% in terms of net enzyme activity was achieved compared to previously reported studies. This is perhaps the first report dealing with the use of P. notatum for AXE production under batch culture SSF. The Plackett-Burman model terms were found highly significant (HS, suggesting the potential commercial utility of the culture used (df = 3, LSD = 0.126.

  20. An optimized fed-batch culture strategy integrated with a one-step fermentation improves L-lactic acid production by Rhizopus oryzae.

    Science.gov (United States)

    Fu, Yongqian; Sun, Xiaolong; Zhu, Huayue; Jiang, Ru; Luo, Xi; Yin, Longfei

    2018-05-21

    In previous work, we proposed a novel modified one-step fermentation fed-batch strategy to efficiently generate L-lactic acid (L-LA) using Rhizopus oryzae. In this study, to further enhance efficiency of L-LA production through one-step fermentation in fed-batch cultures, we systematically investigated the initial peptone- and glucose-feeding approaches, including different initial peptone and glucose concentrations and maintained residual glucose levels. Based on the results of this study, culturing R. oryzae with initial peptone and glucose concentrations of 3.0 and 50.0 g/l, respectively, using a fed-batch strategy is an effective approach of producing L-LA through one-step fermentation. Changing the residual glucose had no obvious effect on the generation of L-LA. We determined the maximum LA production and productivity to be 162 g/l and 6.23 g/(l·h), respectively, during the acid production stage. Compared to our previous work, there was almost no change in L-LA production or yield; however, the productivity of L-LA increased by 14.3%.

  1. Changes of in vivo fluxes through central metabolic pathways during the production of nystatin by Streptomyces noursei in batch culture

    DEFF Research Database (Denmark)

    Jonsbu, E.; Christensen, Bjarke; Nielsen, Jens

    2001-01-01

    The central carbon metabolism of the nystatin-producing strain Streptomyces noursei ATCC 11455 was evaluated by C-13-labelling experiments. A batch fermentation was examined during the idiophase by GC-MS measurements of the labelling patterns of amino acids in the biomass. The labelling patterns...

  2. Metabolic switches and adaptations deduced from the proteomes of Streptomyces coelicolor wild type and phoP mutant grown in batch culture.

    Science.gov (United States)

    Thomas, Louise; Hodgson, David A; Wentzel, Alexander; Nieselt, Kay; Ellingsen, Trond E; Moore, Jonathan; Morrissey, Edward R; Legaie, Roxane; Wohlleben, Wolfgang; Rodríguez-García, Antonio; Martín, Juan F; Burroughs, Nigel J; Wellington, Elizabeth M H; Smith, Margaret C M

    2012-02-01

    Bacteria in the genus Streptomyces are soil-dwelling oligotrophs and important producers of secondary metabolites. Previously, we showed that global messenger RNA expression was subject to a series of metabolic and regulatory switches during the lifetime of a fermentor batch culture of Streptomyces coelicolor M145. Here we analyze the proteome from eight time points from the same fermentor culture and, because phosphate availability is an important regulator of secondary metabolite production, compare this to the proteome of a similar time course from an S. coelicolor mutant, INB201 (ΔphoP), defective in the control of phosphate utilization. The proteomes provide a detailed view of enzymes involved in central carbon and nitrogen metabolism. Trends in protein expression over the time courses were deduced from a protein abundance index, which also revealed the importance of stress pathway proteins in both cultures. As expected, the ΔphoP mutant was deficient in expression of PhoP-dependent genes, and several putatively compensatory metabolic and regulatory pathways for phosphate scavenging were detected. Notably there is a succession of switches that coordinately induce the production of enzymes for five different secondary metabolite biosynthesis pathways over the course of the batch cultures.

  3. Endoplasmic Reticulum-Associated rht-PA Processing in CHO Cells: Influence of Mild Hypothermia and Specific Growth Rates in Batch and Chemostat Cultures.

    Directory of Open Access Journals (Sweden)

    Mauricio Vergara

    Full Text Available Chinese hamster ovary (CHO cells are the main host for producing recombinant proteins with human therapeutic applications mainly because of their capability to perform proper folding and glycosylation processes. In addition, mild hypothermia is one of the main strategies for maximising the productivity of these systems. However, little information is available on the effect of culture temperature on the folding and degradation processes of recombinant proteins that takes place in the endoplasmic reticulum.In order to evaluate the effect of the mild hypothermia on processing/endoplasmatic reticulum-associated degradation (ERAD processes, batch cultures of CHO cells producing recombinant human tissue plasminogen activator (rht-PA were carried out at two temperatures (37°C and 33°C and treated with specific inhibitors of glycosylation and ERAD I (Ubiquitin/Proteasome system or ERAD II (Autophagosoma/Lisosomal system pathways. The effect of mild hypothermia was analysed separately from its indirect effect on specific cell growth rate. To do this, chemostat cultures were carried out at the same incubation conditions as the batch cultures, controlling cell growth at high (0.017 h-1 and low (0.012 h-1 dilution rates. For a better understanding of the investigated phenomenon, cell behaviour was also analysed using principal component analysis (PCA.Results suggest that rht-PA is susceptible to degradation by both ERAD pathways studied, revealing that processing and/or ERAD processes are sensitive to temperature cultivation in batch culture. Moreover, by isolating the effect of culture temperature from the effect of cell growth rate verifyed by using chemostat cultures, we have found that processing and/or ERAD processes are more sensitive to reduction in specific growth rate than low temperature, and that temperature reduction may have a positive effect on protein processing. Interestingly, PCA indicated that the integrated performance displayed by CHO

  4. The Role of the Repeat in the Bear Feast in Traditional Khanty Culture

    Directory of Open Access Journals (Sweden)

    Anna A. Grinevich (Zorkoltseva

    2012-09-01

    Full Text Available This paper is devoted to a role of repeat in Khanty folklore. Songs of a bear feast have served as the source material for the research. The author traces the role of a repeat at different text levels: structure, lexical level, and plot. The repeat is proposed as a fundamental method of traditional Khanty arts.

  5. Repeatability of differential goat bulk milk culture and associations with somatic cell count, total bacterial count, and standard plate count

    OpenAIRE

    Koop, G.; Dik, N.; Nielen, M.; Lipman, L.J.A.

    2010-01-01

    The aims of this study were to assess how different bacterial groups in bulk milk are related to bulk milk somatic cell count (SCC), bulk milk total bacterial count (TBC), and bulk milk standard plate count (SPC) and to measure the repeatability of bulk milk culturing. On 53 Dutch dairy goat farms, 3 bulk milk samples were collected at intervals of 2 wk. The samples were cultured for SPC, coliform count, and staphylococcal count and for the presence of Staphylococcus aureus. Furthermore, SCC ...

  6. Second-Grade Urban Learners: Preliminary Findings for a Computer-Assisted, Culturally Relevant, Repeated Reading Intervention

    Science.gov (United States)

    Bennett, Jessica G.; Gardner, Ralph, III; Cartledge, Gwendolyn; Ramnath, Rajiv; Council, Morris R., III

    2017-01-01

    This study investigated the effects of a multicomponent, supplemental intervention on the reading fluency of second-grade African-American urban students who showed reading and special education risk. The packaged intervention combined repeated readings and culturally relevant stories, delivered through a novel computer software program to enhance…

  7. Repeatability of differential goat bulk milk culture and associations with somatic cell count, total bacterial count, and standard plate count

    NARCIS (Netherlands)

    Koop, G.; Dik, N.; Nielen, M.; Lipman, L.J.A.

    2010-01-01

    The aims of this study were to assess how different bacterial groups in bulk milk are related to bulk milk somatic cell count (SCC), bulk milk total bacterial count (TBC), and bulk milk standard plate count (SPC) and to measure the repeatability of bulk milk culturing. On 53 Dutch dairy goat farms,

  8. Growth of aspergillus terreus and the production of itaconic acid in batch and continuous cultures. The influence of pH

    Energy Technology Data Exchange (ETDEWEB)

    Rychtera, M.; Wase, J.D.A.

    1981-01-01

    Aspergillus terreus (NRRL 1960) was cultivated in batch and in continuous single-stage culture. The influence of pH on the growth of the organism, on the formation of itaconic acid and on the kinetics of fermentation was studied under phosphate limitation, both at controlled ph values and also when the pH was allowed to decrease in a natural way. In the pH range 1.7-3.5, the ratio of undissociated:half-dissociated acid varied from 190:1 to 1.5:1. The amount of completely dissociated acid may be regarded as negligible. In batch systems operated without pH control, an initial pH of 3.1 proved to be the most effective. Product formation under such conditions started at a point where the exponential growth phase commenced and was described by a zero-order equation. The maximum itaconic acid production rate was shifted behind maximum growth rate. The continuous single-stage system was first order with respect to product formation. At pH greater than 3.1, a number of aberrant and pellet forms of the mould occurred, resulting in decreased acid production. (Refs. 41).

  9. Consolidated bioprocessing of microalgal biomass to carboxylates by a mixed culture of cow rumen bacteria using anaerobic sequencing batch reactor (ASBR).

    Science.gov (United States)

    Zhao, Baisuo; Liu, Jie; Frear, Craig; Holtzapple, Mark; Chen, Shulin

    2016-12-01

    This study employed mixed-culture consolidated bioprocessing (CBP) to digest microalgal biomass in an anaerobic sequencing batch reactor (ASBR). The primary objectives are to evaluate the impact of hydraulic residence time (HRT) on the productivity of carboxylic acids and to characterize the bacterial community. HRT affects the production rate and patterns of carboxylic acids. For the 5-L laboratory-scale fermentation, a 12-day HRT was selected because it offered the highest productivity of carboxylic acids and it synthesized longer chains. The variability of the bacterial community increased with longer HRT (R 2 =0.85). In the 5-L laboratory-scale fermentor, the most common phyla were Firmicutes (58.3%), Bacteroidetes (27.4%), and Proteobacteria (11.9%). The dominant bacterial classes were Clostridia (29.8%), Bacteroidia (27.4%), Tissierella (26.2%), and Betaproteobacteria (8.9%). Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Stochastic models to study the impact of mixing on a fed-batch culture of Saccharomyces cerevisiae.

    Science.gov (United States)

    Delvigne, F; Lejeune, A; Destain, J; Thonart, P

    2006-01-01

    The mechanisms of interaction between microorganisms and their environment in a stirred bioreactor can be modeled by a stochastic approach. The procedure comprises two submodels: a classical stochastic model for the microbial cell circulation and a Markov chain model for the concentration gradient calculus. The advantage lies in the fact that the core of each submodel, i.e., the transition matrix (which contains the probabilities to shift from a perfectly mixed compartment to another in the bioreactor representation), is identical for the two cases. That means that both the particle circulation and fluid mixing process can be analyzed by use of the same modeling basis. This assumption has been validated by performing inert tracer (NaCl) and stained yeast cells dispersion experiments that have shown good agreement with simulation results. The stochastic model has been used to define a characteristic concentration profile experienced by the microorganisms during a fermentation test performed in a scale-down reactor. The concentration profiles obtained in this way can explain the scale-down effect in the case of a Saccharomyces cerevisiae fed-batch process. The simulation results are analyzed in order to give some explanations about the effect of the substrate fluctuation dynamics on S. cerevisiae.

  11. Efficiency of biological activator formulated material (BAFM) for volatile organic compounds removal--preliminary batch culture tests with activated sludge.

    Science.gov (United States)

    Corre, Charline; Couriol, Catherine; Amrane, Abdeltif; Dumont, Eric; Andrès, Yves; Le Cloirec, Pierre

    2012-01-01

    During biological degradation, such as biofiltration of air loaded with volatile organic compounds, the pollutant is passed through a bed packed with a solid medium acting as a biofilm support. To improve microorganism nutritional equilibrium and hence to enhance the purification capacities, a Biological Activator Formulated Material (BAFM) was developed, which is a mixture of solid nutrients dissolving slowly in a liquid phase. This solid was previously validated on mineral pollutants: ammonia and hydrogen sulphide. To evaluate the efficiency of such a material for biodegradation of some organic compounds, a simple experiment using an activated sludge batch reactor was carried out. The pollutants (sodium benzoate, phenol, p-nitrophenol and 2-4-dichlorophenol) were in the concentration range 100 to 1200 mg L(-1). The positive impact of the formulated material was shown. The improvement of the degradation rates was in the range 10-30%. This was the consequence of the low dissolution of the nutrients incorporated during material formulation, followed by their consumption by the biomass, as shown for urea used as a nitrogen source. Owing to its twofold interest (mechanical resistance and nutritional supplementation), the Biological Activator Formulated Material seems to be a promising material. Its addition to organic or inorganic supports should be investigated to confirm its relevance for implementation in biofilters.

  12. Key Process Conditions for Production of C4 Dicarboxylic Acids in Bioreactor Batch Cultures of an Engineered Saccharomyces cerevisiae Strain

    NARCIS (Netherlands)

    Zelle, R.M.; De Hulster, E.; Kloezen, W.; Pronk, J.T.; Van Maris, A.J.A.

    2010-01-01

    A recent effort to improve malic acid production by Saccharomyces cerevisiae by means of metabolic engineering resulted in a strain that produced up to 59 g liter(-1) of malate at a yield of 0.42 mol (mol glucose)(-1) in calcium carbonate-buffered shake flask cultures. With shake flasks, process

  13. The effect of growth phase on the lipid class, fatty acid and sterol composition in the marine dinoflagellate, Gymnodinium sp. in batch culture.

    Science.gov (United States)

    Mansour, Maged P; Volkman, John K; Blackburn, Susan I

    2003-05-01

    We have studied the effects of growth phase on the lipid composition in batch cultures of Gymnodinium sp. CS-380/3 over 43 days of culturing. The lipid content increased two fold, from late logarithmic (day 6) to linear growth phase (day 22) then decreased at stationary phase (day 43) while the lipid yield (mg l(-1)) increased 30-fold from day 6 to 30 mg l(-1) at day 43. Changes in fatty acid content mirrored those observed for the total lipid, while the sterol content continued to increase with culture age through to stationary phase. The largest changes occurred in the lipid classes, especially the polar lipids and triacylglycerols (oil). The proportion of triacylglycerols increased from 8% (of total lipids) at day 6 to 30% at day 43, with a concomitant decrease in the polar lipid fraction. The proportions of 16:0 and DHA [22:6(n-3)] increased while those of 18:5(n-3) and EPA [20:5(n-3)] decreased with increasing culture age. The proportion of the major sterol, dinosterol, decreased from 41% (day 6) to 29% (day 43), while the major dinostanol epimer (23R,24R) increased from 33% (day 6) to 38% (day 22). Despite small changes in the proportion of the main sterols, the same sterols were present at all stages of growth, indicating their value as a chemotaxonomic tool for distinguishing between strains within the same genus. Growth phase could be a useful variable for optimising the oil and DHA content with potential for aquaculture feeds and a source of DHA-rich oils for nutraceuticals.

  14. Production of Gymnemic Acid Depends on Medium, Explants, PGRs, Color Lights, Temperature, Photoperiod, and Sucrose Sources in Batch Culture of Gymnema sylvestre

    Directory of Open Access Journals (Sweden)

    A. Bakrudeen Ali Ahmed

    2012-01-01

    Full Text Available Gymnema sylvestre (R.Br. is an important diabetic medicinal plant which yields pharmaceutically active compounds called gymnemic acid (GA. The present study describes callus induction and the subsequent batch culture optimization and GA quantification determined by linearity, precision, accuracy, and recovery. Best callus induction of GA was noticed in MS medium combined with 2,4-D (1.5 mg/L and KN (0.5 mg/L. Evaluation and isolation of GA from the calluses derived from different plant parts, namely, leaf, stem and petioles have been done in the present case for the first time. Factors such as light, temperature, sucrose, and photoperiod were studied to observe their effect on GA production. Temperature conditions completely inhibited GA production. Out of the different sucrose concentrations tested, the highest yield (35.4 mg/g d.w was found at 5% sucrose followed by 12 h photoperiod (26.86 mg/g d.w. Maximum GA production (58.28 mg/g d.w was observed in blue light. The results showed that physical and chemical factors greatly influence the production of GA in callus cultures of G. sylvestre. The factors optimized for in vitro production of GA during the present study can successfully be employed for their large-scale production in bioreactors.

  15. Applying constructivism to nursing education in cultural competence: a course that bears repeating.

    Science.gov (United States)

    Hunter, Jennifer L

    2008-10-01

    A graduate course on culture, diversity, and cultural competence was developed based on constructivist learning theory and Campinha-Bacote's constructs of cultural awareness, knowledge, skill, and encounters. The epistemology, structure, assignments, and activities used in both online and classroom courses were highly effective and well received by the students. Student course evaluations and outcome assessments of students' cultural competence levels, as compared to precourse levels, provided supportive evidence that the course design produced intended outcomes. Course resources are shared, making them available for use by others in cultural competence education.

  16. Strengthening leadership as a catalyst for enhanced patient safety culture: a repeated cross-sectional experimental study.

    Science.gov (United States)

    Kristensen, Solvejg; Christensen, Karl Bang; Jaquet, Annette; Møller Beck, Carsten; Sabroe, Svend; Bartels, Paul; Mainz, Jan

    2016-05-13

    Current literature emphasises that clinical leaders are in a position to enable a culture of safety, and that the safety culture is a performance mediator with the potential to influence patient outcomes. This paper aims to investigate staff's perceptions of patient safety culture in a Danish psychiatric department before and after a leadership intervention. A repeated cross-sectional experimental study by design was applied. In 2 surveys, healthcare staff were asked about their perceptions of the patient safety culture using the 7 patient safety culture dimensions in the Safety Attitudes Questionnaire. To broaden knowledge and strengthen leadership skills, a multicomponent programme consisting of academic input, exercises, reflections and discussions, networking, and action learning was implemented among the clinical area level leaders. In total, 358 and 325 staff members participated before and after the intervention, respectively. 19 of the staff members were clinical area level leaders. In both surveys, the response rate was >75%. The proportion of frontline staff with positive attitudes improved by ≥5% for 5 of the 7 patient safety culture dimensions over time. 6 patient safety culture dimensions became more positive (increase in mean) (pculture are remarkable, and imply that strengthening the leadership can act as a significant catalyst for patient safety culture improvement. Further studies using a longitudinal study design are recommended to investigate the mechanism behind leadership's influence on patient safety culture, sustainability of improvements over time, and the association of change in the patient safety culture measures with change in psychiatric patient safety outcomes. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  17. Evaluation on prebiotic properties of β-glucan and oligo-β-glucan from mushrooms by human fecal microbiota in fecal batch culture

    Directory of Open Access Journals (Sweden)

    Chiraphon Chaikliang

    2015-11-01

    Full Text Available Background: β-glucan is dietary fiber, a structural polysaccharide, β-linked linear chains of D-glucose polymers with variable frequency of branches. β-glucan is isolated from different sources such as cell walls of baker’s yeast (Saccharomyces cerevisiae, cereals (oat and barley and various species of mushrooms. Among 8 mushrooms in the study, Schizophylum commune Fr and Auricularia auricula Judae had the highest in β-glucan contents and the cheapest cost of mushroom per content of β-glucan, respectively. Even the function of β-glucan on immune modulation has been known however no report on interaction between β-glucan and human gut microbiota. Gut microbiota is thought to have health effects by interaction with non-digestible component particular fermentable dietary fiber. It is important to correlate the specific groups of the microbial communities associated with β-glucan fermentation and the consequential SCFA profiles. β-glucan from mushroom may has potential prebiotic function similar to those from commercial yeast (Saccharomyces cerevisiae β-glucan. Objective: To evaluate on prebiotic properties of soluble β-glucans and oligo-β-glucans from Schizophylum commune Fr and Auricularia auricula Judae by fecal fermentation in batch culture. Methods: In vitro fecal fermentation in anaerobic batch cultures under simulated conditions similar to human colon with human faecal samples from three donors were performed. Comparison on 3 β-glucans and 2 oligo-β-glucans have been studied. Sample was taken at 0 h, 24 h and 48 h to analyze the numbers of bacterial changes by fluorescent in situ hybridization (FISH technique. Short chain fatty acids (SCFA were analyzed by HPLC. The prebiotic index (PI was calculated according to the change of 5 specific bacterial genus within 48 h fermentation. Results: Soluble β-glucan from Auricularia auricula Judae increased numbers of bifidobacteria and lactobacillus significantly (P<0.05. The PI of

  18. Detection of Sialic Acid-Utilising Bacteria in a Caecal Community Batch Culture Using RNA-Based Stable Isotope Probing

    Directory of Open Access Journals (Sweden)

    Wayne Young

    2015-03-01

    Full Text Available Sialic acids are monosaccharides typically found on cell surfaces and attached to soluble proteins, or as essential components of ganglioside structures that play a critical role in brain development and neural transmission. Human milk also contains sialic acid conjugated to oligosaccharides, glycolipids, and glycoproteins. These nutrients can reach the large bowel where they may be metabolised by the microbiota. However, little is known about the members of the microbiota involved in this function. To identify intestinal bacteria that utilise sialic acid within a complex intestinal community, we cultured the caecal microbiota from piglets in the presence of 13C-labelled sialic acid. Using RNA-based stable isotope probing, we identified bacteria that consumed 13C-sialic acid by fractionating total RNA in isopycnic buoyant density gradients followed by 16S rRNA gene analysis. Addition of sialic acid caused significant microbial community changes. A relative rise in Prevotella and Lactobacillus species was accompanied by a corresponding reduction in the genera Escherichia/Shigella, Ruminococcus and Eubacterium. Inspection of isotopically labelled RNA sequences suggests that the labelled sialic acid was consumed by a wide range of bacteria. However, species affiliated with the genus Prevotella were clearly identified as the most prolific users, as solely their RNA showed significantly higher relative shares among the most labelled RNA species. Given the relevance of sialic acid in nutrition, this study contributes to a better understanding of their microbial transformation in the intestinal tract with potential implications for human health.

  19. Response coefficient analysis of a fed-batch bioreactor to dissolved oxygen perturbation in complementary cultures during PHB production

    Directory of Open Access Journals (Sweden)

    Patnaik Pratap R

    2008-03-01

    Full Text Available Abstract Background Although the production of poly-β-hydroxybutyrate (PHB has many biological, energetic and environmental advantages over chemically synthesized polymers, synthetic polymers continue to be produced industrially since the productivities of fermentation processes fr PHB are not yet economically competitive. Improvement of a PHB fermentation requires good understanding and optimization under the realistic conditions of large bioreactors. Laboratory-scale studies have shown that co-cultures of Ralstonia eutropha and Lactobacillus delbrueckii generate better fermentation efficiencies than R. eutropha alone. In large bioreactors, incomplete dispersioin and perturbations in the dissolved oxygen (DO concentration, both of which affect the fermentation, have to be considered. This study analyzes the effect of DO fluctuations on bioreactor performance for both ideal and optimally dispersed broths. Results Response coefficient analysis was employed to obtain quantitative information on the effect of DO perturbations on different variables. Three values of the Peclet number (Pe cheracterized three levels of dispersion: Pe = 0.01 for nearly complete dispersion, Pe = 20 for optimum dispersion and Pe = 60 for insufficient dispersion. The response coefficients (RCs of the pairs of bacterial concentrations and the main substrates, glucose and ammonium chloride, showed contrasting variations with time. Lactate, a critical intermediate, and PHB had similar RC profiles but those of lactate were one to two orders of magnitude larger than other RCs. Significantly, the optimum Pe also resulted in the largest RCs, suggesting a balance between productivity and reactor stability. Conclusion Since R. eutropha requires oxygen for its growth whereas L. delbrueckii does not, fluctuations in the DO concentartion have a strong influence on the fermentation. Apart from this, the mechanism of PHB biosynthesis indicates that control of lactate is a critical

  20. Rich Medium Composition Affects Escherichia coli Survival, Glycation, and Mutation Frequency during Long-Term Batch Culture.

    Science.gov (United States)

    Kram, Karin E; Finkel, Steven E

    2015-07-01

    Bacteria such as Escherichia coli are frequently grown to high density to produce biomolecules for study in the laboratory. To achieve this, cells can be incubated in extremely rich media that increase overall cell yield. In these various media, bacteria may have different metabolic profiles, leading to changes in the amounts of toxic metabolites produced. We have previously shown that stresses experienced during short-term growth can affect the survival of cells during the long-term stationary phase (LTSP). Here, we incubated cells in LB, 2× yeast extract-tryptone (YT), Terrific Broth, or Super Broth medium and monitored survival during the LTSP, as well as other reporters of genetic and physiological change. We observe differential cell yield and survival in all media studied. We propose that differences in long-term survival are the result of changes in the metabolism of components of the media that may lead to increased levels of protein and/or DNA damage. We also show that culture pH and levels of protein glycation, a covalent modification that causes protein damage, affect long-term survival. Further, we measured mutation frequency after overnight incubation and observed a correlation between high mutation frequencies at the end of the log phase and loss of viability after 4 days of LTSP incubation, indicating that mutation frequency is potentially predictive of long-term survival. Since glycation and mutation can be caused by oxidative stress, we measured expression of the oxyR oxidative stress regulator during log-phase growth and found that higher levels of oxyR expression during the log phase are consistent with high mutation frequency and lower cell density during the LTSP. Since these complex rich media are often used when producing large quantities of biomolecules in the laboratory, the observed increase in damage resulting in glycation or mutation may lead to production of a heterogeneous population of plasmids or proteins, which could affect the

  1. Memory reconsolidation, repeating, and working through: Science and culture in psychotherapeutic research and practice.

    Science.gov (United States)

    Levin, Charles

    2015-01-01

    Hypothesizing that an effective common feature in divergent forms of psychotherapy is a process of memory reconsolidation integrating new emotional experiences, Lane et al. usefully shift the focus away from established and/or specialized techniques to deeper questions about the underlying principles of psychotherapeutic change. More research attention to cultural factors influencing the definition and treatment of psychopathology is also needed.

  2. Repeated Stimulation of Cultured Networks of Rat Cortical Neurons Induces Parallel Memory Traces

    Science.gov (United States)

    le Feber, Joost; Witteveen, Tim; van Veenendaal, Tamar M.; Dijkstra, Jelle

    2015-01-01

    During systems consolidation, memories are spontaneously replayed favoring information transfer from hippocampus to neocortex. However, at present no empirically supported mechanism to accomplish a transfer of memory from hippocampal to extra-hippocampal sites has been offered. We used cultured neuronal networks on multielectrode arrays and…

  3. Pro Spring Batch

    CERN Document Server

    Minella, Michael T

    2011-01-01

    Since its release, Spring Framework has transformed virtually every aspect of Java development including web applications, security, aspect-oriented programming, persistence, and messaging. Spring Batch, one of its newer additions, now brings the same familiar Spring idioms to batch processing. Spring Batch addresses the needs of any batch process, from the complex calculations performed in the biggest financial institutions to simple data migrations that occur with many software development projects. Pro Spring Batch is intended to answer three questions: *What? What is batch processing? What

  4. Amiodarone biokinetics, the formation of its major oxidative metabolite and neurotoxicity after acute and repeated exposure of brain cell cultures.

    Science.gov (United States)

    Pomponio, Giuliana; Zurich, Marie-Gabrielle; Schultz, Luise; Weiss, Dieter G; Romanelli, Luca; Gramowski-Voss, Alexandra; Di Consiglio, Emma; Testai, Emanuela

    2015-12-25

    The difficulty in mimicking nervous system complexity and cell-cell interactions as well as the lack of kinetics information has limited the use of in vitro neurotoxicity data. Here, we assessed the biokinetic profile as well as the neurotoxicity of Amiodarone after acute and repeated exposure in two advanced rodent brain cell culture models, consisting of both neurons and glial cells organized in 2 or 3 dimensions to mimic the brain histiotypic structure and function. A strategy was applied to evidence the abiotic processes possibly affecting Amiodarone in vitro bioavailability, showing its ability to adsorb to the plastic devices. At clinically relevant Amiodarone concentrations, known to induce neurotoxicity in some patients during therapeutic treatment, a complete uptake was observed in both models in 24 h, after single exposure. After repeated treatments, bioaccumulation was observed, especially in the 3D cell model, together with a greater alteration of neurotoxicity markers. After 14 days, Amiodarone major oxidative metabolite (mono-N-desethylamiodarone) was detected at limited levels, indicating the presence of active drug metabolism enzymes (i.e. cytochrome P450) in both models. The assessment of biokinetics provides useful information on the relevance of in vitro toxicity data and should be considered in the design of an Integrated Testing Strategy aimed to identify specific neurotoxic alerts, and to improve the neurotoxicity assay predictivity for human acute and repeated exposure. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Cell culture-induced gradual and frequent epigenetic reprogramming of invertedly repeated tobacco transgene epialleles

    Czech Academy of Sciences Publication Activity Database

    Křížová, Kateřina; Fojtová, Miloslava; Depicker, A.; Kovařík, Aleš

    2009-01-01

    Roč. 149, č. 3 (2009), s. 1493-1504 ISSN 0032-0889 R&D Projects: GA AV ČR(CZ) IAA600040611; GA ČR(CZ) GD204/05/H505; GA ČR(CZ) GA521/07/0116 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : tobacco * cell culture * transgene silencing Subject RIV: BO - Biophysics Impact factor: 6.235, year: 2009

  6. Simultaneous Transformation of Commingled Trichloroethylene, Tetrachloroethylene, and 1,4-Dioxane by a Microbially Driven Fenton Reaction in Batch Liquid Cultures

    Science.gov (United States)

    Sekar, Ramanan; Taillefert, Martial

    2016-01-01

    ABSTRACT Improper disposal of 1,4-dioxane and the chlorinated organic solvents trichloroethylene (TCE) and tetrachloroethylene (also known as perchloroethylene [PCE]) has resulted in widespread contamination of soil and groundwater. In the present study, a previously designed microbially driven Fenton reaction system was reconfigured to generate hydroxyl (HO˙) radicals for simultaneous transformation of source zone levels of single, binary, and ternary mixtures of TCE, PCE, and 1,4-dioxane. The reconfigured Fenton reaction system was driven by fed batch cultures of the Fe(III)-reducing facultative anaerobe Shewanella oneidensis amended with lactate, Fe(III), and contaminants and exposed to alternating anaerobic and aerobic conditions. To avoid contaminant loss due to volatility, the Fe(II)-generating, hydrogen peroxide-generating, and contaminant transformation phases of the microbially driven Fenton reaction system were separated. The reconfigured Fenton reaction system transformed TCE, PCE, and 1,4-dioxane either as single contaminants or as binary and ternary mixtures. In the presence of equimolar concentrations of PCE and TCE, the ratio of the experimentally derived rates of PCE and TCE transformation was nearly identical to the ratio of the corresponding HO˙ radical reaction rate constants. The reconfigured Fenton reaction system may be applied as an ex situ platform for simultaneous degradation of commingled TCE, PCE, and 1,4-dioxane and provides valuable information for future development of in situ remediation technologies. IMPORTANCE A microbially driven Fenton reaction system [driven by the Fe(III)-reducing facultative anaerobe S. oneidensis] was reconfigured to transform source zone levels of TCE, PCE, and 1,4-dioxane as single contaminants or as binary and ternary mixtures. The microbially driven Fenton reaction may thus be applied as an ex situ platform for simultaneous degradation of at least three (and potentially more) commingled contaminants

  7. Regulation of Autotrophic and Heterotrophic Metabolism in Pseudomonas oxalaticus OX1. Growth on Fructose and on Mixtures of Fructose and Formate in Batch and Continuous Cultures

    NARCIS (Netherlands)

    Dijkhuizen, L.; Harder, W.

    1984-01-01

    In Pseudomonas oxalaticus the synthesis of enzymes involved in autotrophic CO2 fixation via the Calvin cycle is regulated by repression/derepression. During growth of the organism on fructose alone, the synthesis of ribulosebisphosphate carboxylase (RuBPCase) remained fully repressed, both in batch

  8. Umbilical cord Wharton's jelly repeated culture system: a new device and method for obtaining abundant mesenchymal stem cells for bone tissue engineering.

    Directory of Open Access Journals (Sweden)

    Zhengqi Chang

    Full Text Available To date, various types of cells for seeding regenerative scaffolds have been used for bone tissue engineering. Among seed cells, the mesenchymal stem cells derived from human umbilical cord Wharton's jelly (hUCMSCs represent a promising candidate and hold potential for bone tissue engineering due to the the lack of ethical controversies, accessibility, sourced by non-invasive procedures for donors, a reduced risk of contamination, osteogenic differentiation capacities, and higher immunomodulatory capacity. However, the current culture methods are somewhat complicated and inefficient and often fail to make the best use of the umbilical cord (UC tissues. Moreover, these culture processes cannot be performed on a large scale and under strict quality control. As a result, only a small quantity of cells can be harvested using the current culture methods. To solve these problems, we designed and evaluated an UC Wharton's jelly repeated culture device. Using this device, hUCMSCs were obtained from the repeated cultures and their quantities and biological characteristics were compared. We found that using our culture device, which retained all tissue blocks on the bottom of the dish, the total number of obtained cells increased 15-20 times, and the time required for the primary passage was reduced. Moreover, cells harvested from the repeated cultures exhibited no significant difference in their immunophenotype, potential for multilineage differentiation, or proliferative, osteoinductive capacities, and final osteogenesis. The application of the repeated culture frame (RCF not only made full use of the Wharton's jelly but also simplified and specified the culture process, and thus, the culture efficiency was significantly improved. In summary, abundant hUCMSCs of dependable quality can be acquired using the RCF.

  9. A fast approach to determine a fed batch feeding profile for recombinant Pichia pastoris strains

    Directory of Open Access Journals (Sweden)

    Herwig Christoph

    2011-10-01

    Full Text Available Abstract Background The microorganism Pichia pastoris is a commonly used microbial host for the expression of recombinant proteins in biotechnology and biopharmaceutical industry. To speed up process development, a fast methodology to determine strain characteristic parameters, which are needed to subsequently set up fed batch feeding profiles, is required. Results Here, we show the general applicability of a novel approach to quantify a certain minimal set of bioprocess-relevant parameters, i.e. the adaptation time of the culture to methanol, the specific substrate uptake rate during the adaptation phase and the maximum specific substrate uptake rate, based on fast and easy-to-do batch cultivations with repeated methanol pulses in a batch culture. A detailed analysis of the adaptation of different P. pastoris strains to methanol was conducted and revealed that each strain showed very different characteristics during adaptation, illustrating the need of individual screenings for an optimal parameter definition during this phase. Based on the results obtained in batch cultivations, dynamic feeding profiles based on the specific substrate uptake rate were employed for different P. pastoris strains. In these experiments the maximum specific substrate uptake rate, which had been defined in batch experiments, also represented the upper limit of methanol uptake, underlining the validity of the determined process-relevant parameters and the overall experimental strategy. Conclusion In this study, we show that a fast approach to determine a minimal set of strain characteristic parameters based on easy-to-do batch cultivations with methanol pulses is generally applicable for different P. pastoris strains and that dynamic fed batch strategies can be designed on the specific substrate uptake rate without running the risk of methanol accumulation.

  10. Spring batch essentials

    CERN Document Server

    Rao, P Raja Malleswara

    2015-01-01

    If you are a Java developer with basic knowledge of Spring and some experience in the development of enterprise applications, and want to learn about batch application development in detail, then this book is ideal for you. This book will be perfect as your next step towards building simple yet powerful batch applications on a Java-based platform.

  11. On-line monitoring of important organoleptic methyl-branched aldehydes during batch fermentation of starter culture Staphylococcus xylosus reveal new insight into their production in a model fermentation

    DEFF Research Database (Denmark)

    de Vos Petersen, Christian; Beck, Hans Christian; Lauritsen, Frants R

    2004-01-01

    A small fermentor (55 mL) was directly interfaced to a membrane inlet mass spectrometer for continuous on-line monitoring of oxygen and volatile metabolites during batch fermentations of the starter culture Staphylococcus xylosus. Using this technique, we were able to correlate production...... of a longer aerobic growth period. Growing S. xylosus under conditions resembling those in a fermented sausage revealed that NaCl (5%) increased aldehyde production considerably, whereas KNO(3) (0.03%) or NaNO(2) (0.03%) had little effect. A lowering of pH from 7.2 to 6.0 reduced cell density, but had a minor...

  12. Complement consumption by double culture of Paramecium caudatum and Aerobacter cloacae in repeated examination in relation to the individual radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Bernasovsky, I; Cabadaj, S; Praslicka, M; Chlebovska, K [Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie

    1976-01-01

    Two sets of rats were repeatedly examined by the complement consumption test with a double culture of Paramecium caudatum and Aerobacter cloacae (DPA). The first set was examined 11 days and 1 day before irradiation with 0.15 C/kg, the second 6 days before and 4 days after irradiation with 0.15 C/kg. The intensity of reaction and thus the relative titres of the examined antibodies were expressed numerically by the NMHD symbol, i.e., by the number of minimal hemolytical complement doses consumed in the reaction. This reaction is known as the NMHD test. The proportion of rats with a high NMHD which survived 30 days after irradiation was higher than that of rats with low reaction values. Rats having in one examination a high NMHD value and in the second a low one (the sequence high-low or low-high is not important) were more radioresistant than those with permanently low reaction values and did not basically differ from the animals with permanently high NMHD values. Bacteriae Aerobacter cloacae represent the antigenically effective substance of DNA.

  13. Complement consumption by double culture of Paramecium caudatum and Aerobacter cloacae in repeated examination in relation to the individual radiosensitivity

    International Nuclear Information System (INIS)

    Bernasovsky, I.; Cabadaj, S.; Praslicka, M.; Chlebovska, K.

    1976-01-01

    Two sets of rats were repeatedly examined by the complement consumption test with a double culture of Paramecium caudatum and Aerobacter cloacae (DPA). The first set was examined 11 days and 1 day before irradiation with 0.15 C/kg, the second 6 days before and 4 days after irradiation with 0.15 C/kg. The intensity of reaction and thus the relative titres of the examined antibodies were expressed numerically by the NMHD symbol, i.e., by the number of minimal hemolytical complement doses consumed in the reaction. This reaction is known as the NMHD test. The proportion of rats with a high NMHD which survived 30 days after irradiation was higher than that of rats with low reaction values. Rats having in one examination a high NMHD value and in the second a low one (the sequence high-low or low-high is not important) were more radioresistant than those with permanently low reaction values and did not basically differ from the animals with permanently high NMHD values. Bacteriae Aerobacter cloacae represent the antigenically effective substance of DNA. (author)

  14. Influences of incubation temperature and various saccharides on the production of organic acids and gases by gut microbes of rainbow trout Oncorhynchus mykiss in a micro-scale batch culture.

    Science.gov (United States)

    Kihara, M; Sakata, T

    2001-08-01

    We studied the influence of incubation temperature and additional saccharides on the metabolism of hindgut microbes of the rainbow trout Oncorhynchus mykiss in a 50 microl-scale batch culture system. Intestinal contents of rainbow trout reared at 15 degrees C were incubated with glucose, lactosucrose, sodium alginate or colloidal chitin (each 10 g/l) at 15 degrees C or 25 degrees C for 12 h. Levels of organic acids at 0 h and 12 h of incubation were quantified with HPLC. We also monitored gas release from these cultures during incubation. The main product was iso-butyric acid, except for the cultures with colloidal chitin where no net production of organic acids was observed. We detected higher levels of iso-butyric acid in cultures with lactosucrose than in the other cultures. Net production of this acid was less in cultures with colloidal chitin than in blank cultures. The volume of released gas was larger when incubated at 25 degrees C than at 15 degrees C. Cultures with colloidal chitin released more gas than blank cultures when they were incubated at 15 degrees C. Cultures with sodium alginate released less gas than blank cultures irrespective of incubation temperature. These results indicate that the hindgut microbes of this carnivorous fish mainly produce branched-chain fatty acids, very likely by microbial digestion of nitrogenous materials rather than saccharides. However, additional saccharides affected production of branched-chain fatty acids. The influence of incubation temperature in the present study also suggested that the environmental temperature of host fish should affect microbial digestion in the fish gut.

  15. The Utility of Repeat Culture in Fungal Corneal Ulcer Management: A Secondary Analysis of the MUTT-I Randomized Clinical Trial.

    Science.gov (United States)

    Ray, Kathryn J; Lalitha, Prajna; Prajna, N Venkatesh; Rajaraman, Revathi; Krishnan, Tiruvengada; Srinivasan, Muthiah; Ryg, Peter; McLeod, Stephen; Acharya, Nisha R; Lietman, Thomas M; Rose-Nussbaumer, Jennifer

    2017-06-01

    To determine whether patients who had a positive repeated culture was predictive of worse clinical outcome than those who achieved microbiological cure at 6 days in the Mycotic Ulcer Treatment Trial I (MUTT-I). Secondary analysis from a multicenter, double-masked, randomized clinical trial. setting: Multiple hospital sites of the Aravind Eye Care System, India. Patients with culture-positive filamentous fungal ulcers and visual acuity of 20/40 to 20/400 reexamined 6 days after initiation of treatment. Corneal scraping and cultures were obtained from study participants at day 6 after enrollment. We assessed 3-month best spectacle-corrected visual acuity (BSCVA), 3-month infiltrate/scar size, corneal perforation, and re-epithelialization rates stratified by culture positivity at day 6. Of the 323 patients with smear-positive ulcers enrolled in MUTT-I, 299 (92.6%) were scraped and cultured 6 days after enrollment. Repeat culture positivity was 31% (92/299). Among patients who tested positive at enrollment, those with positive 6-day cultures had significantly worse 3-month BSCVA (0.39 logMAR; 95% confidence interval [CI]: 0.24-0.44; P cure on culture is a predictor of clinical response to treatment. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Temperature and pH optima of enzyme activities produced by cellulolytic thermophilic fungi in batch and solid-state cultures

    Energy Technology Data Exchange (ETDEWEB)

    Grajek, W

    1986-01-01

    The temperature and pH optima of cellulolytic activities produced by thermophilic fungi in liquid and solid-state cultures were established. Some differences in optimal conditions for enzyme activities, which depended on culture methods, were confirmed. 10 references.

  17. SPS batch spacing optimisation

    CERN Document Server

    Velotti, F M; Carlier, E; Goddard, B; Kain, V; Kotzian, G

    2017-01-01

    Until 2015, the LHC filling schemes used the batch spac-ing as specified in the LHC design report. The maximumnumber of bunches injectable in the LHC directly dependson the batch spacing at injection in the SPS and hence onthe MKP rise time.As part of the LHC Injectors Upgrade project for LHCheavy ions, a reduction of the batch spacing is needed. In thisdirection, studies to approach the MKP design rise time of150ns(2-98%) have been carried out. These measurementsgave clear indications that such optimisation, and beyond,could be done also for higher injection momentum beams,where the additional slower MKP (MKP-L) is needed.After the successful results from 2015 SPS batch spacingoptimisation for the Pb-Pb run [1], the same concept wasthought to be used also for proton beams. In fact, thanksto the SPS transverse feed back, it was already observedthat lower batch spacing than the design one (225ns) couldbe achieved. For the 2016 p-Pb run, a batch spacing of200nsfor the proton beam with100nsbunch spacing wasreque...

  18. Multi-locus variable-number tandem repeat profiling of Salmonella enterica serovar Typhi isolates from blood cultures and gallbladder specimens from Makassar, South-Sulawesi, Indonesia.

    Directory of Open Access Journals (Sweden)

    Mochammad Hatta

    Full Text Available Multi-locus variable-number tandem repeat analysis differentiated 297 Salmonella enterica serovar Typhi blood culture isolates from Makassar in 76 genotypes and a single unique S. Typhi genotype was isolated from the cholecystectomy specimens of four patients with cholelithiasis. The high diversity in S. Typhi genotypes circulating in Makassar indicates that the number of carriers could be very large, which may complicate disease prevention and control.

  19. Short communication: Repeatability of differential goat bulk milk culture and associations with somatic cell count, total bacterial count, and standard plate count.

    Science.gov (United States)

    Koop, G; Dik, N; Nielen, M; Lipman, L J A

    2010-06-01

    The aims of this study were to assess how different bacterial groups in bulk milk are related to bulk milk somatic cell count (SCC), bulk milk total bacterial count (TBC), and bulk milk standard plate count (SPC) and to measure the repeatability of bulk milk culturing. On 53 Dutch dairy goat farms, 3 bulk milk samples were collected at intervals of 2 wk. The samples were cultured for SPC, coliform count, and staphylococcal count and for the presence of Staphylococcus aureus. Furthermore, SCC (Fossomatic 5000, Foss, Hillerød, Denmark) and TBC (BactoScan FC 150, Foss) were measured. Staphylococcal count was correlated to SCC (r=0.40), TBC (r=0.51), and SPC (r=0.53). Coliform count was correlated to TBC (r=0.33), but not to any of the other variables. Staphylococcus aureus did not correlate to SCC. The contribution of the staphylococcal count to the SPC was 31%, whereas the coliform count comprised only 1% of the SPC. The agreement of the repeated measurements was low. This study indicates that staphylococci in goat bulk milk are related to SCC and make a significant contribution to SPC. Because of the high variation in bacterial counts, repeated sampling is necessary to draw valid conclusions from bulk milk culturing. 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  20. Heuristics for batching and sequencing in batch processing machines

    Directory of Open Access Journals (Sweden)

    Chuda Basnet

    2016-12-01

    Full Text Available In this paper, we discuss the “batch processing” problem, where there are multiple jobs to be processed in flow shops. These jobs can however be formed into batches and the number of jobs in a batch is limited by the capacity of the processing machines to accommodate the jobs. The processing time required by a batch in a machine is determined by the greatest processing time of the jobs included in the batch. Thus, the batch processing problem is a mix of batching and sequencing – the jobs need to be grouped into distinct batches, the batches then need to be sequenced through the flow shop. We apply certain newly developed heuristics to the problem and present computational results. The contributions of this paper are deriving a lower bound, and the heuristics developed and tested in this paper.

  1. Effects of Single and Repeated Exposure to a 50-Hz 2-mT Electromagnetic Field on Primary Cultured Hippocampal Neurons.

    Science.gov (United States)

    Zeng, Ying; Shen, Yunyun; Hong, Ling; Chen, Yanfeng; Shi, Xiaofang; Zeng, Qunli; Yu, Peilin

    2017-06-01

    The prevalence of domestic and industrial electrical appliances has raised concerns about the health risk of extremely low-frequency magnetic fields (ELF-MFs). At present, the effects of ELF-MFs on the central nervous system are still highly controversial, and few studies have investigated its effects on cultured neurons. Here, we evaluated the biological effects of different patterns of ELF-MF exposure on primary cultured hippocampal neurons in terms of viability, apoptosis, genomic instability, and oxidative stress. The results showed that repeated exposure to 50-Hz 2-mT ELF-MF for 8 h per day after different times in culture decreased the viability and increased the production of intracellular reactive oxidative species in hippocampal neurons. The mechanism was potentially related to the up-regulation of Nox2 expression. Moreover, none of the repeated exposure patterns had significant effects on DNA damage, apoptosis, or autophagy, which suggested that ELF-MF exposure has no severe biological consequences in cultured hippocampal neurons.

  2. Prunus dulcis, Batch

    African Journals Online (AJOL)

    STORAGESEVER

    2010-06-07

    Jun 7, 2010 ... almond (Prunus dulcis, Batch) genotypes as revealed by PCR analysis. Yavar Sharafi1*, Jafar Hajilou1, Seyed AbolGhasem Mohammadi2, Mohammad Reza Dadpour1 and Sadollah Eskandari3. 1Department of Horticulture, Faculty of Agriculture, University of Tabriz, Tabriz, 5166614766, Iran.

  3. CHANGES IN CHLOROPHYLL A FLUORENSCENCE AND PIGMENT RATIOS DURING DIFFERENT GROWTH PHASES OF A UNICELLULAR MARINE CHEATOSEROS (BACILLARIOPHYCEAE) IN BATCH CULTURE

    Science.gov (United States)

    Photosystem II reaction centers per cell decreased as the cultures began to decline. The degree of inactivation increased daily as the cell numbers continued to decrease. The concentration of chlorophyll a per cell and the ratio of the major accessory pigments to chlorophyll a (e...

  4. Endoplasmic Reticulum-Associated rht-PA Processing in CHO Cells: Influence of Mild Hypothermia and Specific Growth Rates in Batch and Chemostat Cultures

    OpenAIRE

    Vergara, Mauricio; Berrios, Julio; Mart?nez, Irene; D?az-Barrera, Alvaro; Acevedo, Cristian; Reyes, Juan G.; Gonzalez, Ramon; Altamirano, Claudia

    2015-01-01

    Background Chinese hamster ovary (CHO) cells are the main host for producing recombinant proteins with human therapeutic applications mainly because of their capability to perform proper folding and glycosylation processes. In addition, mild hypothermia is one of the main strategies for maximising the productivity of these systems. However, little information is available on the effect of culture temperature on the folding and degradation processes of recombinant proteins that takes place in ...

  5. Comparison of transcriptional heterogeneity of eight genes between batch Desulfovibrio vulgaris biofilm and planktonic culture at a single-cell level

    Directory of Open Access Journals (Sweden)

    Zhenhua eQi

    2016-04-01

    Full Text Available Sulfate-reducing bacteria (SRB biofilm formed on metal surfaces can change the physicochemical properties of metals and cause metal corrosion. To enhance understanding of differential gene expression in Desulfovibrio vulgaris under planktonic and biofilm growth modes, a single-cell based RT-qPCR approach was applied to determine gene expression levels of 8 selected target genes in four sets of the 31 individual cells isolated from each growth condition (i.e., biofilm formed on a stainless steel (SS) and planktonic cultures, exponential and stationary phases. The results showed obvious gene-expression heterogeneity for the target genes among D. vulgaris single cells of both biofilm and planktonic cultures. In addition, an increased gene-expression heterogeneity in the D. vulgaris biofilm when compared with the planktonic culture was also observed for seven out of eight selected genes, which may be contributing to the increased complexity in terms of structures and morphology in the biofilm. Moreover, the results showed up-regulation of DVU0281 gene encoding exopolysaccharide biosynthesis protein, and down-regulation of genes involved in energy metabolism (i.e., DVU0434 and DVU0588, stress responses (i.e., DVU2410 and response regulator (i.e., DVU3062 in the D. vulgaris biofilm cells. Finally, the gene (DVU2571 involved in iron transportation was found down-regulated, and two genes (DVU1340 and DVU1397 involved in ferric uptake repressor and iron storage were up-regulated in D. vulgaris biofilm, suggesting their possible roles in maintaining normal metabolism of the D. vulgaris biofilm under environments of high concentration of iron. This study showed that the single-cell based analysis could be a useful approach in deciphering metabolism of microbial biofilms.

  6. Modelling of Batch Process Operations

    DEFF Research Database (Denmark)

    Abdul Samad, Noor Asma Fazli; Cameron, Ian; Gani, Rafiqul

    2011-01-01

    Here a batch cooling crystalliser is modelled and simulated as is a batch distillation system. In the batch crystalliser four operational modes of the crystalliser are considered, namely: initial cooling, nucleation, crystal growth and product removal. A model generation procedure is shown that s...

  7. Chip-based human liver-intestine and liver-skin co-cultures--A first step toward systemic repeated dose substance testing in vitro.

    Science.gov (United States)

    Maschmeyer, Ilka; Hasenberg, Tobias; Jaenicke, Annika; Lindner, Marcus; Lorenz, Alexandra Katharina; Zech, Julie; Garbe, Leif-Alexander; Sonntag, Frank; Hayden, Patrick; Ayehunie, Seyoum; Lauster, Roland; Marx, Uwe; Materne, Eva-Maria

    2015-09-01

    Systemic repeated dose safety assessment and systemic efficacy evaluation of substances are currently carried out on laboratory animals and in humans due to the lack of predictive alternatives. Relevant international regulations, such as OECD and ICH guidelines, demand long-term testing and oral, dermal, inhalation, and systemic exposure routes for such evaluations. So-called "human-on-a-chip" concepts are aiming to replace respective animals and humans in substance evaluation with miniaturized functional human organisms. The major technical hurdle toward success in this field is the life-like combination of human barrier organ models, such as intestine, lung or skin, with parenchymal organ equivalents, such as liver, at the smallest biologically acceptable scale. Here, we report on a reproducible homeostatic long-term co-culture of human liver equivalents with either a reconstructed human intestinal barrier model or a human skin biopsy applying a microphysiological system. We used a multi-organ chip (MOC) platform, which provides pulsatile fluid flow within physiological ranges at low media-to-tissue ratios. The MOC supports submerse cultivation of an intact intestinal barrier model and an air-liquid interface for the skin model during their co-culture with the liver equivalents respectively at (1)/100.000 the scale of their human counterparts in vivo. To increase the degree of organismal emulation, microfluidic channels of the liver-skin co-culture could be successfully covered with human endothelial cells, thus mimicking human vasculature, for the first time. Finally, exposure routes emulating oral and systemic administration in humans have been qualified by applying a repeated dose administration of a model substance - troglitazone - to the chip-based co-cultures. Copyright © 2015. Published by Elsevier B.V.

  8. The in vitro biokinetics of chlorpromazine and diazepam in aggregating rat brain cell cultures after repeated exposure

    NARCIS (Netherlands)

    Broeders, Jessica J W; Hermens, Joop L M; Blaauboer, Bas J; Zurich, Marie-Gabrielle

    2015-01-01

    Neurotoxic effects of compounds can be tested in vitro using cell systems. One example is aggregating rat brain cell cultures. For the extrapolation of in vitro data to the in vivo situation, it is important to take the biokinetics of the test compound into account. In addition, the exposure in vivo

  9. Light-optimized growth of cyanobacterial cultures: Growth phases and productivity of biomass and secreted molecules in light-limited batch growth.

    Science.gov (United States)

    Clark, Ryan L; McGinley, Laura L; Purdy, Hugh M; Korosh, Travis C; Reed, Jennifer L; Root, Thatcher W; Pfleger, Brian F

    2018-03-27

    Cyanobacteria are photosynthetic microorganisms whose metabolism can be modified through genetic engineering for production of a wide variety of molecules directly from CO 2 , light, and nutrients. Diverse molecules have been produced in small quantities by engineered cyanobacteria to demonstrate the feasibility of photosynthetic biorefineries. Consequently, there is interest in engineering these microorganisms to increase titer and productivity to meet industrial metrics. Unfortunately, differing experimental conditions and cultivation techniques confound comparisons of strains and metabolic engineering strategies. In this work, we discuss the factors governing photoautotrophic growth and demonstrate nutritionally replete conditions in which a model cyanobacterium can be grown to stationary phase with light as the sole limiting substrate. We introduce a mathematical framework for understanding the dynamics of growth and product secretion in light-limited cyanobacterial cultures. Using this framework, we demonstrate how cyanobacterial growth in differing experimental systems can be easily scaled by the volumetric photon delivery rate using the model organisms Synechococcus sp. strain PCC7002 and Synechococcus elongatus strain UTEX2973. We use this framework to predict scaled up growth and product secretion in 1L photobioreactors of two strains of Synechococcus PCC7002 engineered for production of l-lactate or L-lysine. The analytical framework developed in this work serves as a guide for future metabolic engineering studies of cyanobacteria to allow better comparison of experiments performed in different experimental systems and to further investigate the dynamics of growth and product secretion. Copyright © 2018 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  10. Effects of sulfur and monensin concentrations on in vitro dry matter disappearance, hydrogen sulfide production, and volatile fatty acid concentrations in batch culture ruminal fermentations.

    Science.gov (United States)

    Smith, D R; Dilorenzo, N; Leibovich, J; May, M L; Quinn, M J; Homm, J W; Galyean, M L

    2010-04-01

    Effects of monensin (MON) and S on in vitro fermentation and H(2)S production were evaluated in 2 experiments. In Exp. 1, 2 ruminally cannulated steers were adapted (>14 d) to a 75% concentrate diet [steam-flaked corn (SFC)-based], and ruminal fluid was collected approximately 4 h after feeding. Substrate composed (DM basis) of 85.2% SFC, 9% alfalfa hay, 5% cottonseed meal, and 0.8% urea was added with ruminal fluid and buffer to sealed 125-mL serum bottles to allow for gas collection. A Na(2)SO(4) solution was added to yield S equivalent to 0.2, 0.4, and 0.8% of substrate DM, and MON was included at 0, 2, 4, and 6 mg/L of culture volume. Bottle head-space gas was analyzed for H(2)S. No MON (P = 0.29) or MON x S interaction (P = 0.41) effects were detected for H(2)S production. Increasing S linearly increased (P molar proportions of acetate, butyrate, and the acetate:propionate ratio (A:P), and linearly increased (P 21 d) to a 75% concentrate diet (SFC base) that contained 15% (DM basis) wet corn distillers grains plus solubles (WDGS) and MON at 22 mg/kg of DM. In vitro substrate DM was composed of 75.4% SFC, 15% WDGS, 9% alfalfa hay, and 0.6% urea, and S and MON concentrations were the same as in Exp. 1. No effects of MON (P = 0.93) or the MON x S interaction (P = 0.99) were noted for H(2)S production; however, increasing S linearly increased (P molar proportions of acetate, butyrate, and A:P and linearly increased (P molar proportions were evident with MON regardless of S concentration.

  11. Repeated-batch ethanol fermentation from sweet sorghum juice by ...

    African Journals Online (AJOL)

    . It was found that sweet sorghum juice (SSJ) containing 100 g l-1 of total sugar without nutrient supplement could be used as the low-cost IP medium instead of the typical IP medium or yeast extract malt extract (YM) medium. Ethanol ...

  12. Repeated batch production of vancomycin using synthetic cotton fibers

    African Journals Online (AJOL)

    Administrator

    2011-09-28

    Sep 28, 2011 ... The production of vancomycin by free and immobilized cells of Amycolatopsis orientalis was .... ceutical Industries Company (EIPICO)] and the inhibition zone ... production medium showed a marked loss in the first ... secondary metabolic enzymes of immobilized cells, as ... of cells in an economic way.

  13. Devaki syndrome: a culture-bound psychological reaction in Indian Hindu women in response to repeated pregnancy loss?

    Science.gov (United States)

    Nath, Kamal; Bhattacharya, Arnab; Sinha, Prakriti; Praharaj, Samir Kumar

    2015-02-01

    Depression and anxiety are observed in pregnant women with previous foetal loss due to spontaneous abortions. Culture has important influence on the expression of psychopathology. We report two Hindu women during second trimester of pregnancy with symptoms of depression and anxiety along with identification with a mythological figure - Devaki, with extreme preoccupations with child Krishna and expecting a male child, which precipitated after a series of unfortunate foetal losses. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. CONVERSION OF PINEAPPLE JUICE WASTE INTO LACTIC ACID IN BATCH AND FED – BATCH FERMENTATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    Abdullah Mochamad Busairi

    2012-01-01

    Full Text Available Pineapple juice waste contains valuable components, which are mainly sucrose, glucose, and fructose. Recently, lactic acid has been considered to be an important raw material for the production of biodegradable lactide polymer. The fermentation experiments were carried out in a 3 litres fermentor (Biostat B Model under anaerobic condition with stirring speed of 50 rpm, temperature at 40oC, and pH of 6.00. Effect of feed concentration on lactic acid production, bacterial growth, substrate utilisation and productivity was studied. The results obtained from fed- batch culture fermentation showed that the maximum lactic acid productivity was 0.44 g/L.h for feed concentration of 90 g/L at 48 hours. Whereas the lactic acid productivity obtained from fed-batch culture was twice and half fold higher than that of batch culture productivity.  Buangan jus nanas mengandung komponen yang berharga terutama sukrosa, glukosa, dan fruktosa. Asam laktat adalah bahan baku yang terbaru dan penting untuk dibuat sebagai polimer laktat yang dapat terdegradasi oleh lingkungan. Percobaan dilakukan pada fermentor 3 liter (Model Biostat B di bawah kondisi anaerob dengan kecepatan pengadukan 50 rpm, temperatur 40oC, dan pH 6,00. Pengaruh konsentrasi umpan terhadap produksi asam laktat, pertumbuhan mikroba, pengggunaan substrat dan produktivitas telah dipelajari. Hasil yang didapatkan pada fermentasi dengan menggunakan sistem fed-batch menunjukkan bahwa produktivitas asam laktat maksimum adalah 0.44 g/L,jam dengan konsentrasi umpan, 90 g/L pada waktu 48 jam. Bahkan produktivitas asam laktat yang didapat pada kultur fed-batch lebih tinggi 2,5 kali dari pada proses menggunakan sistem batch

  15. Antipathogenic activity of probiotics against Salmonella Typhimurium and Clostridium difficile in anaerobic batch culture systems: is it due to synergies in probiotic mixtures or the specificity of single strains?

    Science.gov (United States)

    Tejero-Sariñena, Sandra; Barlow, Janine; Costabile, Adele; Gibson, Glenn R; Rowland, Ian

    2013-12-01

    Probiotics are currently being investigated for prevention of infections caused by enteric pathogens. The aim of this in vitro study was to evaluate the influence of three single probiotics: Lactobacillus casei NCIMB 30185 (PXN 37), Lactobacillus acidophilus NCIMB 30184 (PXN 35), Bifidobacterium breve NCIMB 30180 (PXN 25) and a probiotic mixture containing the above strains plus twelve other strains belonging to the Lactobacillus, Bifidobacterium, Lactococcus, Streptococcus and Bacillus genera on the survival of Salmonella Typhimurium and Clostridium difficile using pH-controlled anaerobic batch cultures containing mixed faecal bacteria. Changes in relevant bacterial groups and effects of probiotic addition on survival of the two pathogens were assessed over 24 h. Quantitative analysis of bacterial populations revealed that there was a significant increase in lactobacilli and/or bifidobacteria numbers, depending on probiotic addition, compared with the control (no added probiotic). There was also a significant reduction in S. Typhimurium and C. difficile numbers in the presence of certain probiotics compared with controls. Of the probiotic treatments, two single strains namely L. casei NCIMB 30185 (PXN 37), and B. breve NCIMB 30180 (PXN 25) were the most potent in reducing the numbers of S. Typhimurium and C. difficile. In addition, the supplementation with probiotics into the systems influenced some fermentations parameters. Acetate was found in the largest concentrations in all vessels and lactate and formate were generally detected in higher amounts in vessels with probiotic addition compared to controls. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Progressing batch hydrolysis process

    Science.gov (United States)

    Wright, J.D.

    1985-01-10

    A progressive batch hydrolysis process is disclosed for producing sugar from a lignocellulosic feedstock. It comprises passing a stream of dilute acid serially through a plurality of percolation hydrolysis reactors charged with feed stock, at a flow rate, temperature and pressure sufficient to substantially convert all the cellulose component of the feed stock to glucose. The cooled dilute acid stream containing glucose, after exiting the last percolation hydrolysis reactor, serially fed through a plurality of pre-hydrolysis percolation reactors, charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the hemicellulose component of said feedstock to glucose. The dilute acid stream containing glucose is cooled after it exits the last prehydrolysis reactor.

  17. Butyric acid fermentation of sodium hydroxide pretreated rice straw with undefined mixed culture.

    Science.gov (United States)

    Ai, Binling; Li, Jianzheng; Chi, Xue; Meng, Jia; Liu, Chong; Shi, En

    2014-05-01

    This study describes an alternative mixed culture fermentation technology to anaerobically convert lignocellulosic biomass into butyric acid, a valuable product with wide application, without supplementary cellulolytic enzymes. Rice straw was soaked in 1% NaOH solution to increase digestibility. Among the tested pretreatment conditions, soaking rice straw at 50°C for 72 h removed ~66% of the lignin, but retained ~84% of the cellulose and ~71% of the hemicellulose. By using an undefined cellulose-degrading butyrate-producing microbial community as butyric acid producer in batch fermentation, about 6 g/l of butyric acid was produced from the pretreated rice straw, which accounted for ~76% of the total volatile fatty acids. In the repeated-batch operation, the butyric acid production declined batch by batch, which was most possibly caused by the shift of microbial community structure monitored by denaturing gradient gel electrophoresis. In this study, batch operation was observed to be more suitable for butyric acid production.

  18. Batch-to-batch uniformity of bacterial community succession and flavor formation in the fermentation of Zhenjiang aromatic vinegar.

    Science.gov (United States)

    Wang, Zong-Min; Lu, Zhen-Ming; Yu, Yong-Jian; Li, Guo-Quan; Shi, Jin-Song; Xu, Zheng-Hong

    2015-09-01

    Solid-state fermentation of traditional Chinese vinegar is a mixed-culture refreshment process that proceeds for many centuries without spoilage. Here, we investigated bacterial community succession and flavor formation in three batches of Zhenjiang aromatic vinegar using pyrosequencing and metabolomics approaches. Temporal patterns of bacterial succession in the Pei (solid-state vinegar culture) showed no significant difference (P > 0.05) among three batches of fermentation. In all the batches investigated, the average number of community operational taxonomic units (OTUs) decreased dramatically from 119 ± 11 on day 1 to 48 ± 16 on day 3, and then maintained in the range of 61 ± 9 from day 5 to the end of fermentation. We confirmed that, within a batch of fermentation process, the patterns of bacterial diversity between the starter (took from the last batch of vinegar culture on day 7) and the Pei on day 7 were similar (90%). The relative abundance dynamics of two dominant members, Lactobacillus and Acetobacter, showed high correlation (coefficient as 0.90 and 0.98 respectively) among different batches. Furthermore, statistical analysis revealed dynamics of 16 main flavor metabolites were stable among different batches. The findings validate the batch-to-batch uniformity of bacterial community succession and flavor formation accounts for the quality of Zhenjiang aromatic vinegar. Based on our understanding, this is the first study helps to explain the rationality of age-old artistry from a scientific perspective. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Deployment Repeatability

    Science.gov (United States)

    2016-04-01

    evaluating the deployment repeatability builds upon the testing or analysis of deployment kinematics (Chapter 6) and adds repetition. Introduction...material yield or failure during a test. For the purposes of this chapter, zero shift will refer to permanent changes in the structure, while reversible ...the content of other chapters in this book: Gravity Compensation (Chapter 4) and Deployment Kinematics and Dynamics (Chapter 6). Repeating the

  20. Kubernetes as a batch scheduler

    OpenAIRE

    Souza, Clenimar; Brito Da Rocha, Ricardo

    2017-01-01

    This project aims at executing a CERN batch use case using Kubernetes, in order to figure out what are the advantages and disadvantages, as well as the functionality that can be replicated or is missing. The reference for the batch system is the CERN Batch System, which uses HTCondor. Another goal of this project is to evaluate the current status of federated resources in Kubernetes, in comparison to the single-cluster API resources. Finally, the last goal of this project is to implement buil...

  1. Data-driven batch schuduling

    Energy Technology Data Exchange (ETDEWEB)

    Bent, John [Los Alamos National Laboratory; Denehy, Tim [GOOGLE; Arpaci - Dusseau, Remzi [UNIV OF WISCONSIN; Livny, Miron [UNIV OF WISCONSIN; Arpaci - Dusseau, Andrea C [NON LANL

    2009-01-01

    In this paper, we develop data-driven strategies for batch computing schedulers. Current CPU-centric batch schedulers ignore the data needs within workloads and execute them by linking them transparently and directly to their needed data. When scheduled on remote computational resources, this elegant solution of direct data access can incur an order of magnitude performance penalty for data-intensive workloads. Adding data-awareness to batch schedulers allows a careful coordination of data and CPU allocation thereby reducing the cost of remote execution. We offer here new techniques by which batch schedulers can become data-driven. Such systems can use our analytical predictive models to select one of the four data-driven scheduling policies that we have created. Through simulation, we demonstrate the accuracy of our predictive models and show how they can reduce time to completion for some workloads by as much as 80%.

  2. Poster - 14: Batch Effect Reduction in in-vitro Raman Microscopic Radiosensitivity Study Using Ovarian Cancer Cells

    International Nuclear Information System (INIS)

    Moradi, Hamid; Murugkar, Sangeeta; Ahmad, Abrar; Shepherdson, Dean; Nyiri, Balazs; Vuong, Nhung; Niedbala, Gosia; Vanderhyden, Barbara; Eapen, Libni

    2016-01-01

    Purpose: To improve classification by reducing batch effect in samples from the ovarian carcinoma cell lines A2780s (parental wild type) and A2780cp (cisplatin cross-radio-resistant), before, right after, and 24 hours after irradiation to 10Gy. Methods: Spectra were acquired with a home built confocal Raman microscope in 3 distinct runs of six samples: unirradiated s&cp (control pair), then 0h and 24h after irradiation. The Raman spectra were noise reduced, then background subtracted with SMIRF algorithm. ∼35 cell spectra were collected from each sample in 1024 channels from 700cm-1 to 1618cm-1. The spectra were analyzed by regularized multiclass LDA. For feature reduction the spectra were grouped into 3 overlapping group pairs: s-cp, 0Gy–10Gy0h and 0Gy10–Gy24h. The three features, the three differences of the mean spectra were mapped to the analysis sub-space by the inverse regularized covariance matrix. The batch effect noticeably confounded the dose and time effect. Results: To remove the batch effect, the 2+2=4D subspace extended by the covariance matrix of the means of the 0Gy control groups was subtracted from the spectra of each sample. Repeating the analysis on the spectra with the control group variability removed, the batch effect was dramatically reduced in the dose and time directions enabling sharp linear discrimination. The cell type classification also improved. Conclusions: We identified a efficient batch effect removal technique crucial to the applicability of Raman microscopy to radiosensitivity studies both on cell cultures and potential clinical diagnostic applications.

  3. Poster - 14: Batch Effect Reduction in in-vitro Raman Microscopic Radiosensitivity Study Using Ovarian Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Moradi, Hamid; Murugkar, Sangeeta; Ahmad, Abrar; Shepherdson, Dean; Nyiri, Balazs; Vuong, Nhung; Niedbala, Gosia; Vanderhyden, Barbara; Eapen, Libni [Carleton University, Carleton University, Carleton University, Carleton University, The Ottawa Hospital Cancer Centre, University of Ottawa, The Ottawa Hospital Cancer Centre, University of Ottawa, The Ottawa Hospital Cancer Centre (Canada)

    2016-08-15

    Purpose: To improve classification by reducing batch effect in samples from the ovarian carcinoma cell lines A2780s (parental wild type) and A2780cp (cisplatin cross-radio-resistant), before, right after, and 24 hours after irradiation to 10Gy. Methods: Spectra were acquired with a home built confocal Raman microscope in 3 distinct runs of six samples: unirradiated s&cp (control pair), then 0h and 24h after irradiation. The Raman spectra were noise reduced, then background subtracted with SMIRF algorithm. ∼35 cell spectra were collected from each sample in 1024 channels from 700cm-1 to 1618cm-1. The spectra were analyzed by regularized multiclass LDA. For feature reduction the spectra were grouped into 3 overlapping group pairs: s-cp, 0Gy–10Gy0h and 0Gy10–Gy24h. The three features, the three differences of the mean spectra were mapped to the analysis sub-space by the inverse regularized covariance matrix. The batch effect noticeably confounded the dose and time effect. Results: To remove the batch effect, the 2+2=4D subspace extended by the covariance matrix of the means of the 0Gy control groups was subtracted from the spectra of each sample. Repeating the analysis on the spectra with the control group variability removed, the batch effect was dramatically reduced in the dose and time directions enabling sharp linear discrimination. The cell type classification also improved. Conclusions: We identified a efficient batch effect removal technique crucial to the applicability of Raman microscopy to radiosensitivity studies both on cell cultures and potential clinical diagnostic applications.

  4. Response variation in a batch of TLDS

    International Nuclear Information System (INIS)

    Burrage, J.; Campbell, A.

    2004-01-01

    Full text: At Royal Perth Hospital, LiF thermoluminescent dosimeter rods (TLDs) are handled in batches of 50. Rods in each batch are always annealed together to ensure the same thermal history and an individual batch is used with the same type and energy of radiation. A subset of a batch is used for calibration purposes by exposing them to a range of known doses and their output is used to calculate the dose received by other rods used for a dose measurement. Variation in TLD response is addressed by calculating 95% certainty levels from the calibration rods and applying this to the dose measurement rods. This approach relies on the sensitivity of rods within each batch being similar. This work investigates the validity of this assumption and considers possible benefits of applying individual rod sensitivities. The variation in response of TLD rods was assessed using 25 TLD-100 rods (Harshaw/Bicron) which were uniformly exposed to 1 Gy using 6 MeV photons in a linear accelerator on 5 separate occasions. Rods were read with a Harshaw 5500 reader. During the read process the Harshaw reader periodically checks for noise and PMT gain drift and the data were corrected for these parameters. Replicate exposure data were analysed using 1-way Analysis of Variance (ANOVA) to determine whether the between rod variations were significantly different to the variations within a single rod. A batch of 50 rods was also exposed on three occasions using the above technique. Individual TLD rod sensitivity values were determined using the rod responses from 2 exposures and these values were applied to correct charges on a rod-by-rod basis for the third exposure. ANOVA results on the 5 exposures of 25 rods showed the variance between rods was significantly greater than the within rod variance (p < 0.001). The precision of an individual rod was estimated to have a standard deviation of 2.8%. This suggests that the 95% confidence limits for repeated measurements using the same dose and

  5. Repeating Marx

    DEFF Research Database (Denmark)

    Fuchs, Christian; Monticelli, Lara

    2018-01-01

    This introduction sets out the context of the special issue “Karl Marx @ 200: Debating Capitalism & Perspectives for the Future of Radical Theory”, which was published on the occasion of Marx’s bicentenary on 5 May 2018. First, we give a brief overview of contemporary capitalism’s development...... and its crises. Second, we argue that it is important to repeat Marx today. Third, we reflect on lessons learned from 200 years of struggles for alternatives to capitalism. Fourth, we give an overview of the contributions in this special issue. Taken together, the contributions in this special issue show...... that Marx’s theory and politics remain key inspirations for understanding exploitation and domination in 21st-century society and for struggles that aim to overcome these phenomena and establishing a just and fair society. We need to repeat Marx today....

  6. Deployment Repeatability

    Science.gov (United States)

    2016-08-31

    large cohort of trials to spot unusual cases. However, deployment repeatability is inherently a nonlinear phenomenon, which makes modeling difficult...and GEMS tip position were both tracked during ground testing by a laser target tracking system. Earlier SAILMAST testing in 2005 [8] used...recalls the strategy used by SRTM, where a constellation of lights was installed at the tip of the boom and a modified star tracker was used to track tip

  7. Design of common heat exchanger network for batch processes

    International Nuclear Information System (INIS)

    Anastasovski, Aleksandar

    2014-01-01

    Heat integration of energy streams is very important for the efficient energy recovery in production systems. Pinch technology is a very useful tool for heat integration and maximizing energy efficiency. Creating of heat exchangers network as a common solution for systems in batch mode that will be applicable in all existing time slices is very difficult. This paper suggests a new methodology for design of common heat exchanger network for batch processes. Heat exchanger network designs were created for all determined repeatable and non-repeatable time periods – time slices. They are the basis for creating the common heat exchanger network. The common heat exchanger network as solution, satisfies all heat-transfer needs for each time period and for every existing combination of selected streams in the production process. This methodology use split of some heat exchangers into two or more heat exchange units or heat exchange zones. The reason for that is the multipurpose use of heat exchangers between different pairs of streams in different time periods. Splitting of large heat exchangers would maximize the total heat transfer usage of heat exchange units. Final solution contains heat exchangers with the minimum heat load as well as the minimum need of heat transfer area. The solution is applicable for all determined time periods and all existing stream combinations. - Highlights: •Methodology for design of energy efficient systems in batch processes. •Common Heat Exchanger Network solution based on designs with Pinch technology. •Multipurpose use of heat exchangers in batch processes

  8. BatchJS: Implementing Batches in JavaScript

    NARCIS (Netherlands)

    D. Kasemier

    2014-01-01

    htmlabstractNone of our popular programming languages know how to handle distribution well. Yet our programs interact more and more with each other and our data resorts in databases and web services. Batches are a new addition to languages that can finally bring native support for distribution to

  9. High solid fed-batch butanol fermentation with simultaneous product recovery: part II - process integration.

    Science.gov (United States)

    In these studies liquid hot water (LHW) pretreated and enzymatically hydrolyzed Sweet Sorghum Bagasse (SSB) hydrolyzates were fermented in a fed-batch reactor. As reported in the preceding paper, the culture was not able to ferment the hydrolyzate I in a batch process due to presence of high level o...

  10. Simulated Batch Production of Penicillin

    Science.gov (United States)

    Whitaker, A.; Walker, J. D.

    1973-01-01

    Describes a program in applied biology in which the simulation of the production of penicillin in a batch fermentor is used as a teaching technique to give students experience before handling a genuine industrial fermentation process. Details are given for the calculation of minimum production cost. (JR)

  11. NDA BATCH 2002-02

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence Livermore National Laboratory

    2009-12-09

    QC sample results (daily background checks, 20-gram and 100-gram SGS drum checks) were within acceptable criteria established by WIPP's Quality Assurance Objectives for TRU Waste Characterization. Replicate runs were performed on 5 drums with IDs LL85101099TRU, LL85801147TRU, LL85801109TRU, LL85300999TRU and LL85500979TRU. All replicate measurement results are identical at the 95% confidence level as established by WIPP criteria. Note that the batch covered 5 weeks of SGS measurements from 23-Jan-2002 through 22-Feb-2002. Data packet for SGS Batch 2002-02 generated using gamma spectroscopy with the Pu Facility SGS unit is technically reasonable. All QC samples are in compliance with established control limits. The batch data packet has been reviewed for correctness, completeness, consistency and compliance with WIPP's Quality Assurance Objectives and determined to be acceptable. An Expert Review was performed on the data packet between 28-Feb-02 and 09-Jul-02 to check for potential U-235, Np-237 and Am-241 interferences and address drum cases where specific scan segments showed Se gamma ray transmissions for the 136-keV gamma to be below 0.1 %. Two drums in the batch showed Pu-238 at a relative mass ratio more than 2% of all the Pu isotopes.

  12. Batching System for Superior Service

    Science.gov (United States)

    2001-01-01

    Veridian's Portable Batch System (PBS) was the recipient of the 1997 NASA Space Act Award for outstanding software. A batch system is a set of processes for managing queues and jobs. Without a batch system, it is difficult to manage the workload of a computer system. By bundling the enterprise's computing resources, the PBS technology offers users a single coherent interface, resulting in efficient management of the batch services. Users choose which information to package into "containers" for system-wide use. PBS also provides detailed system usage data, a procedure not easily executed without this software. PBS operates on networked, multi-platform UNIX environments. Veridian's new version, PBS Pro,TM has additional features and enhancements, including support for additional operating systems. Veridian distributes the original version of PBS as Open Source software via the PBS website. Customers can register and download the software at no cost. PBS Pro is also available via the web and offers additional features such as increased stability, reliability, and fault tolerance.A company using PBS can expect a significant increase in the effective management of its computing resources. Tangible benefits include increased utilization of costly resources and enhanced understanding of computational requirements and user needs.

  13. Production of tea vinegar by batch and semicontinuous fermentation

    OpenAIRE

    Kaur, Pardeep; Kocher, G. S.; Phutela, R. P.

    2010-01-01

    The fermented tea vinegar combines the beneficial properties of tea and vinegar. The complete fermentation takes 4 to 5 weeks in a batch culture and thus can be shortened by semi continuous/ continuous fermentation using immobilized bacterial cells. In the present study, alcoholic fermentation of 1.0 and 1.5% tea infusions using Saccharomyces cerevisae G was carried out that resulted in 84.3 and 84.8% fermentation efficiency (FE) respectively. The batch vinegar fermentation of these wines wit...

  14. NGBAuth - Next Generation Batch Authentication for long running batch jobs.

    CERN Document Server

    Juto, Zakarias

    2015-01-01

    This document describes the prototyping of a new solution for the CERN batch authentication of long running jobs. While the job submission requires valid user credentials, these have to be renewed due to long queuing and execution times. Described within is a new system which will guarantee a similar level of security as the old LSFAuth while simplifying the implementation and the overall architecture. The new system is being built on solid, streamlined and tested components (notably OpenSSL) and a priority has been to make it more generic in order to facilitate the evolution of the current system such as for the expected migration from LSF to Condor as backend batch system.

  15. PROOF on a Batch System

    International Nuclear Information System (INIS)

    Behrenhoff, W; Ehrenfeld, W; Samson, J; Stadie, H

    2011-01-01

    The 'parallel ROOT facility' (PROOF) from the ROOT framework provides a mechanism to distribute the load of interactive and non-interactive ROOT sessions on a set of worker nodes optimising the overall execution time. While PROOF is designed to work on a dedicated PROOF cluster, the benefits of PROOF can also be used on top of another batch scheduling system with the help of temporary per user PROOF clusters. We will present a lightweight tool which starts a temporary PROOF cluster on a SGE based batch cluster or, via a plugin mechanism, e.g. on a set of bare desktops via ssh. Further, we will present the result of benchmarks which compare the data throughput for different data storage back ends available at the German National Analysis Facility (NAF) at DESY.

  16. The patient safety culture as perceived by staff at two different emergency departments before and after introducing a flow-oriented working model with team triage and lean principles: a repeated cross-sectional study.

    Science.gov (United States)

    Burström, Lena; Letterstål, Anna; Engström, Marie-Louise; Berglund, Anders; Enlund, Mats

    2014-07-09

    Patient safety is of the utmost importance in health care. The patient safety culture in an institution has great impact on patient safety. To enhance patient safety and to design strategies to reduce medical injuries, there is a current focus on measuring the patient safety culture. The aim of the present study was to describe the patient safety culture in an ED at two different hospitals before and after a Quality improvement (QI) project that was aimed to enhance patient safety. A repeated cross-sectional design, using the Hospital Survey On Patient Safety Culture questionnaire before and after a quality improvement project in two emergency departments at a county hospital and a university hospital. The questionnaire was developed to obtain a better understanding of the patient safety culture of an entire hospital or of specific departments. The Swedish version has 51 questions and 15 dimensions. At the county hospital, a difference between baseline and follow-up was observed in three dimensions. For two of these dimensions, Team-work within hospital and Communication openness, a higher score was measured at the follow-up. At the university hospital, a higher score was measured at follow-up for the two dimensions Team-work across hospital units and Team-work within hospital. The result showed changes in the self-estimated patient safety culture, mainly regarding team-work and communication openness. Most of the improvements at follow-up were seen by physicians, and mainly at the county hospital.

  17. Culture.

    Science.gov (United States)

    Smith, Timothy B; Rodríguez, Melanie Domenech; Bernal, Guillermo

    2011-02-01

    This article summarizes the definitions, means, and research of adapting psychotherapy to clients' cultural backgrounds. We begin by reviewing the prevailing definitions of cultural adaptation and providing a clinical example. We present an original meta-analysis of 65 experimental and quasi-experimental studies involving 8,620 participants. The omnibus effect size of d = .46 indicates that treatments specifically adapted for clients of color were moderately more effective with that clientele than traditional treatments. The most effective treatments tended to be those with greater numbers of cultural adaptations. Mental health services targeted to a specific cultural group were several times more effective than those provided to clients from a variety of cultural backgrounds. We recommend a series of research-supported therapeutic practices that account for clients' culture, with culture-specific treatments being more effective than generally culture-sensitive treatments. © 2010 Wiley Periodicals, Inc.

  18. A Model-based B2B (Batch to Batch) Control for An Industrial Batch Polymerization Process

    Science.gov (United States)

    Ogawa, Morimasa

    This paper describes overview of a model-based B2B (batch to batch) control for an industrial batch polymerization process. In order to control the reaction temperature precisely, several methods based on the rigorous process dynamics model are employed at all design stage of the B2B control, such as modeling and parameter estimation of the reaction kinetics which is one of the important part of the process dynamics model. The designed B2B control consists of the gain scheduled I-PD/II2-PD control (I-PD with double integral control), the feed-forward compensation at the batch start time, and the model adaptation utilizing the results of the last batch operation. Throughout the actual batch operations, the B2B control provides superior control performance compared with that of conventional control methods.

  19. Monte Carlo simulation on kinetics of batch and semi-batch free radical polymerization

    KAUST Repository

    Shao, Jing; Tang, Wei; Xia, Ru; Feng, Xiaoshuang; Chen, Peng; Qian, Jiasheng; Song, Changjiang

    2015-01-01

    experimental and simulation studies, we showed the capability of our Monte Carlo scheme on representing polymerization kinetics in batch and semi-batch processes. Various kinetics information, such as instant monomer conversion, molecular weight

  20. Capacity Planning for Batch and Perfusion Bioprocesses Across Multiple Biopharmaceutical Facilities

    OpenAIRE

    Siganporia, Cyrus C; Ghosh, Soumitra; Daszkowski, Thomas; Papageorgiou, Lazaros G; Farid, Suzanne S

    2014-01-01

    Production planning for biopharmaceutical portfolios becomes more complex when products switch between fed-batch and continuous perfusion culture processes. This article describes the development of a discrete-time mixed integer linear programming (MILP) model to optimize capacity plans for multiple biopharmaceutical products, with either batch or perfusion bioprocesses, across multiple facilities to meet quarterly demands. The model comprised specific features to account for products with fe...

  1. Family based dispatching with batch availability

    NARCIS (Netherlands)

    van der Zee, D.J.

    2013-01-01

    Family based dispatching rules seek to lower set-up frequencies by grouping (batching) similar types of jobs for joint processing. Hence shop flow times may be improved, as less time is spent on set-ups. Motivated by an industrial project we study the control of machines with batch availability,

  2. Modeling of Fusarium redolens Dzf2 mycelial growth kinetics and optimal fed-batch fermentation for beauvericin production.

    Science.gov (United States)

    Xu, Li-Jian; Liu, Yuan-Shuai; Zhou, Li-Gang; Wu, Jian-Yong

    2011-09-01

    Beauvericin (BEA) is a cyclic hexadepsipeptide mycotoxin with notable phytotoxic and insecticidal activities. Fusarium redolens Dzf2 is a highly BEA-producing fungus isolated from a medicinal plant. The aim of the current study was to develop a simple and valid kinetic model for F. redolens Dzf2 mycelial growth and the optimal fed-batch operation for efficient BEA production. A modified Monod model with substrate (glucose) and product (BEA) inhibition was constructed based on the culture characteristics of F. redolens Dzf2 mycelia in a liquid medium. Model parameters were derived by simulation of the experimental data from batch culture. The model fitted closely with the experimental data over 20-50 g l(-1) glucose concentration range in batch fermentation. The kinetic model together with the stoichiometric relationships for biomass, substrate and product was applied to predict the optimal feeding scheme for fed-batch fermentation, leading to 54% higher BEA yield (299 mg l(-1)) than in the batch culture (194 mg l(-1)). The modified Monod model incorporating substrate and product inhibition was proven adequate for describing the growth kinetics of F. redolens Dzf2 mycelial culture at suitable but not excessive initial glucose levels in batch and fed-batch cultures.

  3. Uneven batch data alignment with application to the control of batch end-product quality.

    Science.gov (United States)

    Wan, Jian; Marjanovic, Ognjen; Lennox, Barry

    2014-03-01

    Batch processes are commonly characterized by uneven trajectories due to the existence of batch-to-batch variations. The batch end-product quality is usually measured at the end of these uneven trajectories. It is necessary to align the time differences for both the measured trajectories and the batch end-product quality in order to implement statistical process monitoring and control schemes. Apart from synchronizing trajectories with variable lengths using an indicator variable or dynamic time warping, this paper proposes a novel approach to align uneven batch data by identifying short-window PCA&PLS models at first and then applying these identified models to extend shorter trajectories and predict future batch end-product quality. Furthermore, uneven batch data can also be aligned to be a specified batch length using moving window estimation. The proposed approach and its application to the control of batch end-product quality are demonstrated with a simulated example of fed-batch fermentation for penicillin production. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

  4. In vitro systems toxicology approach to investigate the effects of repeated cigarette smoke exposure on human buccal and gingival organotypic epithelial tissue cultures.

    Science.gov (United States)

    Schlage, Walter K; Iskandar, Anita R; Kostadinova, Radina; Xiang, Yang; Sewer, Alain; Majeed, Shoaib; Kuehn, Diana; Frentzel, Stefan; Talikka, Marja; Geertz, Marcel; Mathis, Carole; Ivanov, Nikolai; Hoeng, Julia; Peitsch, Manuel C

    2014-10-01

    Smoking has been associated with diseases of the lung, pulmonary airways and oral cavity. Cytologic, genomic and transcriptomic changes in oral mucosa correlate with oral pre-neoplasia, cancer and inflammation (e.g. periodontitis). Alteration of smoking-related gene expression changes in oral epithelial cells is similar to that in bronchial and nasal epithelial cells. Using a systems toxicology approach, we have previously assessed the impact of cigarette smoke (CS) seen as perturbations of biological processes in human nasal and bronchial organotypic epithelial culture models. Here, we report our further assessment using in vitro human oral organotypic epithelium models. We exposed the buccal and gingival organotypic epithelial tissue cultures to CS at the air-liquid interface. CS exposure was associated with increased secretion of inflammatory mediators, induction of cytochrome P450s activity and overall weak toxicity in both tissues. Using microarray technology, gene-set analysis and a novel computational modeling approach leveraging causal biological network models, we identified CS impact on xenobiotic metabolism-related pathways accompanied by a more subtle alteration in inflammatory processes. Gene-set analysis further indicated that the CS-induced pathways in the in vitro buccal tissue models resembled those in the in vivo buccal biopsies of smokers from a published dataset. These findings support the translatability of systems responses from in vitro to in vivo and demonstrate the applicability of oral organotypical tissue models for an impact assessment of CS on various tissues exposed during smoking, as well as for impact assessment of reduced-risk products.

  5. LSF usage for batch at CERN

    CERN Multimedia

    Schwickerath, Ulrich

    2007-01-01

    Contributed poster to the CHEP07. Original abstract: LSF 7, the latest version of Platform's batch workload management system, addresses many issues which limited the ability of LSF 6.1 to support large scale batch farms, such as the lxbatch service at CERN. In this paper we will present the status of the evaluation and deployment of LSF 7 at CERN, including issues concerning the integration of LSF 7 with the gLite grid middleware suite and, in particular, the steps taken to endure an efficient reporting of the local batch system status and usage to the Grid Information System

  6. Simulation of kefiran production of Lactobacillus kefiranofaciens JCM6985 in fed-batch reactor

    Directory of Open Access Journals (Sweden)

    Benjamas Cheirsilp

    2006-09-01

    Full Text Available Kinetics of kefiran production by Lactobacillus kefiranofaciens JCM6985 has been investigated. A mathematical model taking into account the mechanism of exopolysaccharides production has been developed. Experiments were carried out in batch mode in order to obtain kinetic model parameters that were further applied to simulate fed-batch processes. A simplification of parameter fitting was also introduced for complicated model. The fed-batch mode allows more flexibility in the control of the substrate concentration as well as product concentration in the culture medium. Based on the batch mathematical model, a fed-batch model was developed and simulations were done. Simulation study in fed-batch reactor resulted that substrate concentration should be controlled at 20 g L-1 to soften the product inhibition and also to stimulate utilization of substrate and its hydrolysate. From simulation results of different feeding techniques, it was found that constant feeding at 0.01 L h-1 was most practically effective feeding profile for exopolysaccharides production in fed-batch mode.

  7. Improvement of the butanol production selectivity and butanol to acetone ratio (B:A) by addition of electron carriers in the batch culture of a new local isolate of Clostridium acetobutylicum YM1.

    Science.gov (United States)

    Nasser Al-Shorgani, Najeeb Kaid; Kalil, Mohd Sahaid; Wan Yusoff, Wan Mohtar; Shukor, Hafiza; Hamid, Aidil Abdul

    2015-12-01

    Improvement in the butanol production selectivity or enhanced butanol:acetone ratio (B:A) is desirable in acetone-butanol-ethanol (ABE) fermentation by Clostridium strains. In this study, artificial electron carriers were added to the fermentation medium of a new isolate of Clostridium acetobutylicum YM1 in order to improve the butanol yield and B:A ratio. The results revealed that medium supplementation with electron carriers changed the metabolism flux of electron and carbon in ABE fermentation by YM1. A decrease in acetone production, which subsequently improved the B:A ratio, was observed. Further improvement in the butanol production and B:A ratios were obtained when the fermentation medium was supplemented with butyric acid. The maximum butanol production (18.20 ± 1.38 g/L) was gained when a combination of methyl red and butyric acid was added. Although the addition of benzyl viologen (0.1 mM) and butyric acid resulted in high a B:A ratio of 16:1 (800% increment compared with the conventional 2:1 ratio), the addition of benzyl viologen to the culture after 4 h resulted in the production of 18.05 g/L butanol. Manipulating the metabolic flux to butanol through the addition of electron carriers could become an alternative strategy to achieve higher butanol productivity and improve the B:A ratio. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Fuzzy batch controller for granular materials

    OpenAIRE

    Zamyatin Nikolaj; Smirnov Gennadij; Fedorchuk Yuri; Rusina Olga

    2018-01-01

    The paper focuses on batch control of granular materials in production of building materials from fluorine anhydrite. Batching equipment is intended for smooth operation and timely feeding of supply hoppers at a required level. Level sensors and a controller of an asynchronous screw drive motor are used to control filling of the hopper with industrial anhydrite binders. The controller generates a required frequency and ensures required productivity of a feed conveyor. Mamdani-type fuzzy infer...

  9. Batch Computed Tomography Analysis of Projectiles

    Science.gov (United States)

    2016-05-01

    ARL-TR-7681 ● MAY 2016 US Army Research Laboratory Batch Computed Tomography Analysis of Projectiles by Michael C Golt, Chris M...Laboratory Batch Computed Tomography Analysis of Projectiles by Michael C Golt and Matthew S Bratcher Weapons and Materials Research...values to account for projectile variability in the ballistic evaluation of armor. 15. SUBJECT TERMS computed tomography , CT, BS41, projectiles

  10. cultural

    Directory of Open Access Journals (Sweden)

    Irene Kreutz

    2006-01-01

    Full Text Available Es un estudio cualitativo que adoptó como referencial teorico-motodológico la antropología y la etnografía. Presenta las experiencias vivenciadas por mujeres de una comunidad en el proceso salud-enfermedad, con el objetivo de comprender los determinantes sócio-culturales e históricos de las prácticas de prevención y tratamiento adoptados por el grupo cultural por medio de la entrevista semi-estructurada. Los temas que emergieron fueron: la relación entre la alimentación y lo proceso salud-enfermedad, las relaciones con el sistema de salud oficial y el proceso salud-enfermedad y lo sobrenatural. Los dados revelaron que los moradores de la comunidad investigada tienen un modo particular de explicar sus procedimientos terapéuticos. Consideramos que es papel de los profesionales de la salud en sus prácticas, la adopción de abordajes o enfoques que consideren al individuo en su dimensión sócio-cultural e histórica, considerando la enorme diversidad cultural en nuestro país.

  11. Crescimento e composição química de dez espécies de microalgas marinhas em cultivos estanques Growth and chemical composition of ten species of marine microalgae in batch cultures

    Directory of Open Access Journals (Sweden)

    Viviane Borges-Campos

    2010-02-01

    Full Text Available Microalgas apresentam diversas aplicações econômicas consagradas, como usos na aquicultura e na indústria de alimentos, havendo buscas por novos usos, como a geração de biomassa para produção de biodiesel. As possíveis aplicações estão diretamente relacionadas à taxa de crescimento e ao perfil químico das espécies. Assim, a seleção de condições que promovam o aproveitamento da biomassa algácea é fundamental para sua utilização econômica. Neste estudo, 10 espécies de microalgas marinhas foram cultivadas e comparadas quanto ao crescimento e à composição química. Foram observadas diferenças na velocidade de crescimento, com espécies de células menores crescendo mais rapidamente que microalgas maiores. Teores de proteínas, carboidratos, lipídeos e pigmentos fotossintetizantes variaram amplamente entre as espécies, sendo as proteínas as substâncias mais abundantes. Todas as espécies apresentaram concentrações de ácidos aminados semelhantes, sendo os ácidos aspártico e glutâmico os mais abundantes. Algumas espécies apresentaram altas concentrações de ácidos graxos de importância econômica, como os ácidos eicosapentaenoico e linoleico. O balanço dos resultados indica que há poucas tendências gerais relacionadas a grandes grupos taxonômicos.Microalgae show several economic applications, such as uses in aquaculture and in food industry, and there is a search for new uses, such as the biomass production to convert into biodiesel. All possible applications are directly linked to growth rate and the chemical profile of the species. Thus, the selection of conditions to promote a better use of algal biomass is fundamental for economic purposes. In this study, 10 species of marine microalgae were cultured and compared for growth and chemical composition. Remarkable differences of growth performance have been observed, with species with small cell volumes growing faster than species with large cell volumes

  12. Batch Attribute-Based Encryption for Secure Clouds

    Directory of Open Access Journals (Sweden)

    Chen Yang

    2015-10-01

    Full Text Available Cloud storage is widely used by organizations due to its advantage of allowing universal access with low cost. Attribute-based encryption (ABE is a kind of public key encryption suitable for cloud storage. The secret key of each user and the ciphertext are associated with an access policy and an attribute set, respectively; in addition to holding a secret key, one can decrypt a ciphertext only if the associated attributes match the predetermined access policy, which allows one to enforce fine-grained access control on outsourced files. One issue in existing ABE schemes is that they are designed for the users of a single organization. When one wants to share the data with the users of different organizations, the owner needs to encrypt the messages to the receivers of one organization and then repeats this process for another organization. This situation is deteriorated with more and more mobile devices using cloud services, as the ABE encryption process is time consuming and may exhaust the power supplies of the mobile devices quickly. In this paper, we propose a batch attribute-based encryption (BABE approach to address this problem in a provably-secure way. With our approach, the data owner can outsource data in batches to the users of different organizations simultaneously. The data owner is allowed to decide the receiving organizations and the attributes required for decryption. Theoretical and experimental analyses show that our approach is more efficient than traditional encryption implementations in computation and communication.

  13. Atomic-batched tensor decomposed two-electron repulsion integrals

    Science.gov (United States)

    Schmitz, Gunnar; Madsen, Niels Kristian; Christiansen, Ove

    2017-04-01

    We present a new integral format for 4-index electron repulsion integrals, in which several strategies like the Resolution-of-the-Identity (RI) approximation and other more general tensor-decomposition techniques are combined with an atomic batching scheme. The 3-index RI integral tensor is divided into sub-tensors defined by atom pairs on which we perform an accelerated decomposition to the canonical product (CP) format. In a first step, the RI integrals are decomposed to a high-rank CP-like format by repeated singular value decompositions followed by a rank reduction, which uses a Tucker decomposition as an intermediate step to lower the prefactor of the algorithm. After decomposing the RI sub-tensors (within the Coulomb metric), they can be reassembled to the full decomposed tensor (RC approach) or the atomic batched format can be maintained (ABC approach). In the first case, the integrals are very similar to the well-known tensor hypercontraction integral format, which gained some attraction in recent years since it allows for quartic scaling implementations of MP2 and some coupled cluster methods. On the MP2 level, the RC and ABC approaches are compared concerning efficiency and storage requirements. Furthermore, the overall accuracy of this approach is assessed. Initial test calculations show a good accuracy and that it is not limited to small systems.

  14. Energy efficiency of batch and semi-batch (CCRO) reverse osmosis desalination.

    Science.gov (United States)

    Warsinger, David M; Tow, Emily W; Nayar, Kishor G; Maswadeh, Laith A; Lienhard V, John H

    2016-12-01

    As reverse osmosis (RO) desalination capacity increases worldwide, the need to reduce its specific energy consumption becomes more urgent. In addition to the incremental changes attainable with improved components such as membranes and pumps, more significant reduction of energy consumption can be achieved through time-varying RO processes including semi-batch processes such as closed-circuit reverse osmosis (CCRO) and fully-batch processes that have not yet been commercialized or modelled in detail. In this study, numerical models of the energy consumption of batch RO (BRO), CCRO, and the standard continuous RO process are detailed. Two new energy-efficient configurations of batch RO are analyzed. Batch systems use significantly less energy than continuous RO over a wide range of recovery ratios and source water salinities. Relative to continuous RO, models predict that CCRO and batch RO demonstrate up to 37% and 64% energy savings, respectively, for brackish water desalination at high water recovery. For batch RO and CCRO, the primary reductions in energy use stem from atmospheric pressure brine discharge and reduced streamwise variation in driving pressure. Fully-batch systems further reduce energy consumption by not mixing streams of different concentrations, which CCRO does. These results demonstrate that time-varying processes can significantly raise RO energy efficiency. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. The use of fed batch approaches to maximise yields in bacterial fermentation and protein expression

    International Nuclear Information System (INIS)

    McLean, A.

    2001-01-01

    A fermentation facility for the scale up of bacterial and yeast fermentations has been set up at the University of Queensland under the auspices of the ARC Special Research Centre for Functional and Applied Genomics. A major application is the production of recombinant proteins for determination of tertiary structures by X-ray crystallography or nuclear magnetic resonance. For this purpose, large amounts of protein arc needed and the yield from a single fermentation run is crucial to success within constrained laboratory budgets. To achieve maximal yields we are optimising fed batch approaches in bacterial fermentation. Fed batch offers many advantages over batch cultures. Coupled with the ability to monitor online the internal conditions of the fermentation including pH and dissolved oxygen and stirrer cascading functions it is possible to ensure that the nutritional environment of the microorganism is optimised for its growth and or for optimal protein expression. The poster will describe some of our experience in setting up fed batch fermentations and successful applications of fed batches to increasing protein yield. It will also outline services that are available to academic groups outside the University of Queensland For structure determination and functional studies, the production of radiolabelled proteins can also be an advantage. We will describe initial experiments aimed at coupling the principles of fed batch fermentation to the introduction of carbon or nitrogen isotopes into the recombinant protein

  16. Fuzzy batch controller for granular materials

    Directory of Open Access Journals (Sweden)

    Zamyatin Nikolaj

    2018-01-01

    Full Text Available The paper focuses on batch control of granular materials in production of building materials from fluorine anhydrite. Batching equipment is intended for smooth operation and timely feeding of supply hoppers at a required level. Level sensors and a controller of an asynchronous screw drive motor are used to control filling of the hopper with industrial anhydrite binders. The controller generates a required frequency and ensures required productivity of a feed conveyor. Mamdani-type fuzzy inference is proposed for controlling the speed of the screw that feeds mixture components. As related to production of building materials based on fluoride anhydrite, this method is used for the first time. A fuzzy controller is proven to be effective in controlling the filling level of the supply hopper. In addition, the authors determined optimal parameters of the batching process to ensure smooth operation and production of fluorine anhydrite materials of specified properties that can compete with gypsum-based products.

  17. History based batch method preserving tally means

    International Nuclear Information System (INIS)

    Shim, Hyung Jin; Choi, Sung Hoon

    2012-01-01

    In the Monte Carlo (MC) eigenvalue calculations, the sample variance of a tally mean calculated from its cycle-wise estimates is biased because of the inter-cycle correlations of the fission source distribution (FSD). Recently, we proposed a new real variance estimation method named the history-based batch method in which a MC run is treated as multiple runs with small number of histories per cycle to generate independent tally estimates. In this paper, the history-based batch method based on the weight correction is presented to preserve the tally mean from the original MC run. The effectiveness of the new method is examined for the weakly coupled fissile array problem as a function of the dominance ratio and the batch size, in comparison with other schemes available

  18. A Model of Batch Scheduling for a Single Batch Processor with Additional Setups to Minimize Total Inventory Holding Cost of Parts of a Single Item Requested at Multi-due-date

    Science.gov (United States)

    Hakim Halim, Abdul; Ernawati; Hidayat, Nita P. A.

    2018-03-01

    This paper deals with a model of batch scheduling for a single batch processor on which a number of parts of a single items are to be processed. The process needs two kinds of setups, i. e., main setups required before processing any batches, and additional setups required repeatedly after the batch processor completes a certain number of batches. The parts to be processed arrive at the shop floor at the times coinciding with their respective starting times of processing, and the completed parts are to be delivered at multiple due dates. The objective adopted for the model is that of minimizing total inventory holding cost consisting of holding cost per unit time for a part in completed batches, and that in in-process batches. The formulation of total inventory holding cost is derived from the so-called actual flow time defined as the interval between arrival times of parts at the production line and delivery times of the completed parts. The actual flow time satisfies not only minimum inventory but also arrival and delivery just in times. An algorithm to solve the model is proposed and a numerical example is shown.

  19. High cell density fed-batch fermentations for lipase production: feeding strategies and oxygen transfer.

    Science.gov (United States)

    Salehmin, M N I; Annuar, M S M; Chisti, Y

    2013-11-01

    This review is focused on the production of microbial lipases by high cell density fermentation. Lipases are among the most widely used of the enzyme catalysts. Although lipases are produced by animals and plants, industrial lipases are sourced almost exclusively from microorganisms. Many of the commercial lipases are produced using recombinant species. Microbial lipases are mostly produced by batch and fed-batch fermentation. Lipases are generally secreted by the cell into the extracellular environment. Thus, a crude preparation of lipases can be obtained by removing the microbial cells from the fermentation broth. This crude cell-free broth may be further concentrated and used as is, or lipases may be purified from it to various levels. For many large volume applications, lipases must be produced at extremely low cost. High cell density fermentation is a promising method for low-cost production: it allows a high concentration of the biomass and the enzyme to be attained rapidly and this eases the downstream recovery of the enzyme. High density fermentation enhances enzyme productivity compared with the traditional submerged culture batch fermentation. In production of enzymes, a high cell density is generally achieved through fed-batch operation, not through perfusion culture which is cumbersome. The feeding strategies used in fed-batch fermentations for producing lipases and the implications of these strategies are discussed. Most lipase-producing microbial fermentations require oxygen. Oxygen transfer in such fermentations is discussed.

  20. Following an Optimal Batch Bioreactor Operations Model

    DEFF Research Database (Denmark)

    Ibarra-Junquera, V.; Jørgensen, Sten Bay; Virgen-Ortíz, J.J.

    2012-01-01

    The problem of following an optimal batch operation model for a bioreactor in the presence of uncertainties is studied. The optimal batch bioreactor operation model (OBBOM) refers to the bioreactor trajectory for nominal cultivation to be optimal. A multiple-variable dynamic optimization of fed...... as the master system which includes the optimal cultivation trajectory for the feed flow rate and the substrate concentration. The “real” bioreactor, the one with unknown dynamics and perturbations, is considered as the slave system. Finally, the controller is designed such that the real bioreactor...

  1. Supervision of Fed-Batch Fermentations

    DEFF Research Database (Denmark)

    Gregersen, Lars; Jørgensen, Sten Bay

    1999-01-01

    Process faults may be detected on-line using existing measurements based upon modelling that is entirely data driven. A multivariate statistical model is developed and used for fault diagnosis of an industrial fed-batch fermentation process. Data from several (25) batches are used to develop...... a model for cultivation behaviour. This model is validated against 13 data sets and demonstrated to explain a significant amount of variation in the data. The multivariate model may directly be used for process monitoring. With this method faults are detected in real time and the responsible measurements...

  2. Exploring the Transition From Batch to Online

    DEFF Research Database (Denmark)

    Jørgensen, Anker Helms

    2010-01-01

    of the truly interactive use of computers known today. The transition invoked changes in a number of areas: technological, such as hybrid forms between batch and online; organisational such as decentralization; and personal as users and developers alike had to adopt new technology, shape new organizational...... structures, and acquire new skills. This work-in-progress paper extends an earlier study of the transition from batch to online, based on oral history interviews with (ex)-employees in two large Danish Service Bureaus. The paper takes the next step by ana-lyzing a particular genre: the commercial computer...

  3. Improvement of xanthan gum production in batch culture using ...

    African Journals Online (AJOL)

    Yomi

    2011-12-21

    Dec 21, 2011 ... Fermentation was carried out in 500 ml Erlenmeyer flask with 200 ml of a ... The effect of acetic acid on xanthan production was studied with ... improvement when compared with the control. No .... in a plunging jet reactor.

  4. Improvement of xanthan gum production in batch culture using ...

    African Journals Online (AJOL)

    Yomi

    2011-12-21

    Dec 21, 2011 ... In this study, the effect of acetic acid on the improvement of xanthan biosynthesis by Xanthomonas campestris b82 was investigated. ... shown that citric acid that is used as a chelating agent in medium to prevent the ... pH value close to the acid pKa) in the medium in one pulse, 30 h after incubation (at the ...

  5. Medium optimization for protopectinase production by batch culture ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-11

    Nov 11, 2011 ... Optimization of medium compositions for protopectinase production by ... food industry, pharmacy and cosmetic manufacture due to ... energy intensive and industrial wastes (Iglesias and ... group of enzymes, which produce the enzymatic ... development time and overall costs (Pan et al., 2008; Ren.

  6. Valorization of crude glycerol and eggshell biowaste as media components for hydrogen production: A scale-up study using co-culture system.

    Science.gov (United States)

    Pachapur, Vinayak Laxman; Das, Ratul Kumar; Brar, Satinder Kaur; Le Bihan, Yann; Buelna, Gerardo

    2017-02-01

    The properties of eggshells (EGS) as neutralizing and immobilizing agent were investigated for hydrogen (H 2 ) production using crude glycerol (CG) by co-culture system. Eggshells of different sizes and concentrations were used during batch and repeated-batch fermentation. For batch and repeated-batch fermentation, the maximum H 2 production (36.53±0.53 and 41.16±0.95mmol/L, respectively) was obtained with the EGS size of 33μmcomponents, the EGS concentration of 0.25% (w/v) was found to be optimum for maximum H 2 production (31.66±0.55mmol/L) and the production profile was comparable to H 2 production (32.07±0.92mmol/L) obtained with all media components. In scale-up study with semi-continuous bioreactor (7.5L), almost 1.5-fold increase (in comparison to mono-culture) i.e. 312.12mmol-H 2 /L-of medium with 86.65% glycerol utilization was obtained. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Instability of expanded simple tandem repeats is induced in cell culture by a variety of agents: N-Nitroso-N-ethylurea, benzo(a)pyrene, etoposide and okadaic acid

    International Nuclear Information System (INIS)

    Polyzos, Aris; Parfett, Craig; Healy, Caroline; Douglas, George R.; Yauk, Carole L.

    2006-01-01

    Expanded simple tandem repeat (ESTR) sequences have proven useful biomarkers to detect genotoxicity in vivo. Their high sensitivity has been used to assess environmentally relevant doses of mutagens such as ionizing radiation, DNA alkylating agents and airborne particulate pollution, for germline mutations in mouse assays. The mutagenic response involves size alteration of these ESTR loci induced by agents causing a variety of cellular damage. The mechanistic aspects of this induced instability remain unclear and have not been studied in detail. Mechanistic knowledge is important to help understand the relevance of increased ESTR mutation frequencies. In this study, we applied a murine cell culture system to examine induced response to four agents exhibiting different modes of toxic action including: N-nitroso-N-ethylurea (ENU), benzo(a)pyrene (BaP), okadaic acid and etoposide at slightly sub-toxic levels. We used single-molecule-polymerase chain reaction (SM-PCR) to assess the relative mutant frequency after 4-week chemical treatments at the Ms6-hm ESTR sequence of cultured C3H/10T1/2 cells (a mouse embryonic cell line). Increased mutation was observed with both 0.64 mM ENU (1.95-fold increase, P < 0.0001), 1 μM benzo(a)pyrene (1.87-fold increase, P = 0.0006) and 3 nM etoposide (1.89-fold increase, P = 0.0003). The putative ESTR mutagen okadaic acid (1.27-fold increase, P = 0.2289), administered at 0.5 nM, did not affect the C3H/10T1/2 Ms6-hm locus. Therefore, agents inducing small and bulky adducts, and indirectly causing strand breaks through inhibition of topoisomerase, caused similar induction of instability at an ESTR locus at matched toxicities. As size spectra for induced mutations were identical, the data indicate that although these chemicals exhibit distinct modes of action, a similar indirect process is influencing ESTR instability. In contrast, a potent tumour promoter that is a kinase inhibitor does not contribute to induced ESTR instability in cell

  8. Instability of expanded simple tandem repeats is induced in cell culture by a variety of agents: N-Nitroso-N-ethylurea, benzo(a)pyrene, etoposide and okadaic acid

    Energy Technology Data Exchange (ETDEWEB)

    Polyzos, Aris [Environmental Health Centre, Environmental and occupational Toxicology Division, Health Canada, Tunney' s Pasture, P.L. 0803A, Ottawa, Ont., K1A 0L2 (Canada); Parfett, Craig [Environmental Health Centre, Environmental and occupational Toxicology Division, Health Canada, Tunney' s Pasture, P.L. 0803A, Ottawa, Ont., K1A 0L2 (Canada); Healy, Caroline [Environmental Health Centre, Environmental and occupational Toxicology Division, Health Canada, Tunney' s Pasture, P.L. 0803A, Ottawa, Ont., K1A 0L2 (Canada); Douglas, George R. [Environmental Health Centre, Environmental and occupational Toxicology Division, Health Canada, Tunney' s Pasture, P.L. 0803A, Ottawa, Ont., K1A 0L2 (Canada); Yauk, Carole L. [Environmental Health Centre, Environmental and occupational Toxicology Division, Health Canada, Tunney' s Pasture, P.L. 0803A, Ottawa, Ont., K1A 0L2 (Canada)]. E-mail: Carole_Yauk@hc-sc.gc.ca

    2006-06-25

    Expanded simple tandem repeat (ESTR) sequences have proven useful biomarkers to detect genotoxicity in vivo. Their high sensitivity has been used to assess environmentally relevant doses of mutagens such as ionizing radiation, DNA alkylating agents and airborne particulate pollution, for germline mutations in mouse assays. The mutagenic response involves size alteration of these ESTR loci induced by agents causing a variety of cellular damage. The mechanistic aspects of this induced instability remain unclear and have not been studied in detail. Mechanistic knowledge is important to help understand the relevance of increased ESTR mutation frequencies. In this study, we applied a murine cell culture system to examine induced response to four agents exhibiting different modes of toxic action including: N-nitroso-N-ethylurea (ENU), benzo(a)pyrene (BaP), okadaic acid and etoposide at slightly sub-toxic levels. We used single-molecule-polymerase chain reaction (SM-PCR) to assess the relative mutant frequency after 4-week chemical treatments at the Ms6-hm ESTR sequence of cultured C3H/10T1/2 cells (a mouse embryonic cell line). Increased mutation was observed with both 0.64 mM ENU (1.95-fold increase, P < 0.0001), 1 {mu}M benzo(a)pyrene (1.87-fold increase, P = 0.0006) and 3 nM etoposide (1.89-fold increase, P = 0.0003). The putative ESTR mutagen okadaic acid (1.27-fold increase, P = 0.2289), administered at 0.5 nM, did not affect the C3H/10T1/2 Ms6-hm locus. Therefore, agents inducing small and bulky adducts, and indirectly causing strand breaks through inhibition of topoisomerase, caused similar induction of instability at an ESTR locus at matched toxicities. As size spectra for induced mutations were identical, the data indicate that although these chemicals exhibit distinct modes of action, a similar indirect process is influencing ESTR instability. In contrast, a potent tumour promoter that is a kinase inhibitor does not contribute to induced ESTR instability in

  9. Systematic Methodology for Reproducible Optimizing Batch Operation

    DEFF Research Database (Denmark)

    Bonné, Dennis; Jørgensen, Sten Bay

    2006-01-01

    This contribution presents a systematic methodology for rapid acquirement of discrete-time state space model representations of batch processes based on their historical operation data. These state space models are parsimoniously parameterized as a set of local, interdependent models. The present...

  10. Batch extractive distillation for high purity methanol

    International Nuclear Information System (INIS)

    Zhang Weijiang; Ma Sisi

    2006-01-01

    In this paper, the application in chemical industry and microelectronic industry, market status and the present situation of production of high purity methanol at home and abroad were introduced firstly. Purification of industrial methanol for high purity methanol is feasible in china. Batch extractive distillation is the best separation technique for purification of industrial methanol. Dimethyl sulfoxide was better as an extractant. (authors)

  11. Monitoring of batch processes using spectroscopy

    NARCIS (Netherlands)

    Gurden, S. P.; Westerhuis, J. A.; Smilde, A. K.

    2002-01-01

    There is an increasing need for new techniques for the understanding, monitoring and the control of batch processes. Spectroscopy is now becoming established as a means of obtaining real-time, high-quality chemical information at frequent time intervals and across a wide range of industrial

  12. Estimation of the Maximum Theoretical Productivity of Fed-Batch Bioreactors

    Energy Technology Data Exchange (ETDEWEB)

    Bomble, Yannick J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); St. John, Peter C [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Crowley, Michael F [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-10-18

    A key step towards the development of an integrated biorefinery is the screening of economically viable processes, which depends sharply on the yields and productivities that can be achieved by an engineered microorganism. In this study, we extend an earlier method which used dynamic optimization to find the maximum theoretical productivity of batch cultures to explicitly include fed-batch bioreactors. In addition to optimizing the intracellular distribution of metabolites between cell growth and product formation, we calculate the optimal control trajectory of feed rate versus time. We further analyze how sensitive the productivity is to substrate uptake and growth parameters.

  13. Monte Carlo simulation on kinetics of batch and semi-batch free radical polymerization

    KAUST Repository

    Shao, Jing

    2015-10-27

    Based on Monte Carlo simulation technology, we proposed a hybrid routine which combines reaction mechanism together with coarse-grained molecular simulation to study the kinetics of free radical polymerization. By comparing with previous experimental and simulation studies, we showed the capability of our Monte Carlo scheme on representing polymerization kinetics in batch and semi-batch processes. Various kinetics information, such as instant monomer conversion, molecular weight, and polydispersity etc. are readily calculated from Monte Carlo simulation. The kinetic constants such as polymerization rate k p is determined in the simulation without of “steady-state” hypothesis. We explored the mechanism for the variation of polymerization kinetics those observed in previous studies, as well as polymerization-induced phase separation. Our Monte Carlo simulation scheme is versatile on studying polymerization kinetics in batch and semi-batch processes.

  14. 1,3-Propanediol production from crude glycerol by Clostridium butyricum DSP1 in repeated batch

    Directory of Open Access Journals (Sweden)

    Daria Szymanowska-Powałowska

    2014-11-01

    Conclusions: The experiments proved that by using a portion of metabolically active biomass as inoculum for another fermentation formula it is possible to eliminate the stage of inoculum growth and thereby reduce the length of the whole operation. Additionally, that strategy avoids the phase of microbial adaptation to a different source of carbon such as crude glycerol, which is more difficult to utilize, thus improving the kinetic parameters of 1,3-PD production.

  15. Multi-objective optimization of glycopeptide antibiotic production in batch and fed batch processes

    DEFF Research Database (Denmark)

    Maiti, Soumen K.; Eliasson Lantz, Anna; Bhushan, Mani

    2011-01-01

    batch operations using process model for Amycolatopsis balhimycina, a glycopeptide antibiotic producer. This resulted in a set of several pareto optimal solutions with the two objectives ranging from (0.75gl−1, 3.97g$-1) to (0.44gl−1, 5.19g$-1) for batch and from (1.5gl−1, 5.46g$-1) to (1.1gl−1, 6.34g...

  16. Optimization of cyclosporin A production by Beauveria nivea in continuous fed-batch fermentation

    Directory of Open Access Journals (Sweden)

    Dong Huijun

    2011-01-01

    Full Text Available To develop the effective control method for fed-batch culture of cyclosporin A production, we chose fructose, L-valine and (NH42HPO4 as feeding nutrients and compared their productivities in relation to different concentrations. The feeding rate of three kinds of feeding materials was controlled to maintain the suitable residual concentration. The fed-batch fermentation results indicated that the optimal concentrations of fructose, L-valine and (NH42HPO4 were about 20 g/L, 0.5 g/L and 0.6 g/L for cyclosporin A production, respectively. The cultivation of Beauveria nivea could produce cyclosporin A up to 6.2 g/L for 240 hrs through a continuous feeding-rate-controlled-batch process under the optimal feeding conditions.

  17. Medication waste reduction in pediatric pharmacy batch processes.

    Science.gov (United States)

    Toerper, Matthew F; Veltri, Michael A; Hamrock, Eric; Mollenkopf, Nicole L; Holt, Kristen; Levin, Scott

    2014-04-01

    To inform pediatric cart-fill batch scheduling for reductions in pharmaceutical waste using a case study and simulation analysis. A pre and post intervention and simulation analysis was conducted during 3 months at a 205-bed children's center. An algorithm was developed to detect wasted medication based on time-stamped computerized provider order entry information. The algorithm was used to quantify pharmaceutical waste and associated costs for both preintervention (1 batch per day) and postintervention (3 batches per day) schedules. Further, simulation was used to systematically test 108 batch schedules outlining general characteristics that have an impact on the likelihood for waste. Switching from a 1-batch-per-day to a 3-batch-per-day schedule resulted in a 31.3% decrease in pharmaceutical waste (28.7% to 19.7%) and annual cost savings of $183,380. Simulation results demonstrate how increasing batch frequency facilitates a more just-in-time process that reduces waste. The most substantial gains are realized by shifting from a schedule of 1 batch per day to at least 2 batches per day. The simulation exhibits how waste reduction is also achievable by avoiding batch preparation during daily time periods where medication administration or medication discontinuations are frequent. Last, the simulation was used to show how reducing batch preparation time per batch provides some, albeit minimal, opportunity to decrease waste. The case study and simulation analysis demonstrate characteristics of batch scheduling that may support pediatric pharmacy managers in redesign toward minimizing pharmaceutical waste.

  18. Revisiting the TALE repeat.

    Science.gov (United States)

    Deng, Dong; Yan, Chuangye; Wu, Jianping; Pan, Xiaojing; Yan, Nieng

    2014-04-01

    Transcription activator-like (TAL) effectors specifically bind to double stranded (ds) DNA through a central domain of tandem repeats. Each TAL effector (TALE) repeat comprises 33-35 amino acids and recognizes one specific DNA base through a highly variable residue at a fixed position in the repeat. Structural studies have revealed the molecular basis of DNA recognition by TALE repeats. Examination of the overall structure reveals that the basic building block of TALE protein, namely a helical hairpin, is one-helix shifted from the previously defined TALE motif. Here we wish to suggest a structure-based re-demarcation of the TALE repeat which starts with the residues that bind to the DNA backbone phosphate and concludes with the base-recognition hyper-variable residue. This new numbering system is consistent with the α-solenoid superfamily to which TALE belongs, and reflects the structural integrity of TAL effectors. In addition, it confers integral number of TALE repeats that matches the number of bound DNA bases. We then present fifteen crystal structures of engineered dHax3 variants in complex with target DNA molecules, which elucidate the structural basis for the recognition of bases adenine (A) and guanine (G) by reported or uncharacterized TALE codes. Finally, we analyzed the sequence-structure correlation of the amino acid residues within a TALE repeat. The structural analyses reported here may advance the mechanistic understanding of TALE proteins and facilitate the design of TALEN with improved affinity and specificity.

  19. Reconfigurable multiport EPON repeater

    Science.gov (United States)

    Oishi, Masayuki; Inohara, Ryo; Agata, Akira; Horiuchi, Yukio

    2009-11-01

    An extended reach EPON repeater is one of the solutions to effectively expand FTTH service areas. In this paper, we propose a reconfigurable multi-port EPON repeater for effective accommodation of multiple ODNs with a single OLT line card. The proposed repeater, which has multi-ports in both OLT and ODN sides, consists of TRs, BTRs with the CDR function and a reconfigurable electrical matrix switch, can accommodate multiple ODNs to a single OLT line card by controlling the connection of the matrix switch. Although conventional EPON repeaters require full OLT line cards to accommodate subscribers from the initial installation stage, the proposed repeater can dramatically reduce the number of required line cards especially when the number of subscribers is less than a half of the maximum registerable users per OLT. Numerical calculation results show that the extended reach EPON system with the proposed EPON repeater can save 17.5% of the initial installation cost compared with a conventional repeater, and can be less expensive than conventional systems up to the maximum subscribers especially when the percentage of ODNs in lightly-populated areas is higher.

  20. Quantum repeated games revisited

    International Nuclear Information System (INIS)

    Frąckiewicz, Piotr

    2012-01-01

    We present a scheme for playing quantum repeated 2 × 2 games based on Marinatto and Weber’s approach to quantum games. As a potential application, we study the twice repeated Prisoner’s Dilemma game. We show that results not available in the classical game can be obtained when the game is played in the quantum way. Before we present our idea, we comment on the previous scheme of playing quantum repeated games proposed by Iqbal and Toor. We point out the drawbacks that make their results unacceptable. (paper)

  1. Optimal operation of batch membrane processes

    CERN Document Server

    Paulen, Radoslav

    2016-01-01

    This study concentrates on a general optimization of a particular class of membrane separation processes: those involving batch diafiltration. Existing practices are explained and operational improvements based on optimal control theory are suggested. The first part of the book introduces the theory of membrane processes, optimal control and dynamic optimization. Separation problems are defined and mathematical models of batch membrane processes derived. The control theory focuses on problems of dynamic optimization from a chemical-engineering point of view. Analytical and numerical methods that can be exploited to treat problems of optimal control for membrane processes are described. The second part of the text builds on this theoretical basis to establish solutions for membrane models of increasing complexity. Each chapter starts with a derivation of optimal operation and continues with case studies exemplifying various aspects of the control problems under consideration. The authors work their way from th...

  2. Improved production of an enzyme that hydrolyses raw yam starch by Penicillium sp. S-22 using fed-batch fermentation.

    Science.gov (United States)

    Sun, Hai-Yan; Ge, Xiang-Yang; Zhang, Wei-Guo

    2006-11-01

    A newly isolated strain, Penicillium sp. S-22, was used to produce an enzyme that hydrolyses raw yam starch [raw yam starch digesting enzyme (RYSDE)]. The enzyme activity and overall enzyme productivity were respectively 16 U/ml and 0.19 U/ml h in the batch culture. The enzyme activity increased to 85 U/ml by feeding of partially hydrolyzed raw yam starch. When a mixture containing partially hydrolyzed raw yam starch and peptone was fed by a pH-stat strategy, the enzyme activity reached 366 U/ml, 23-fold of that obtained in the batch culture, and the overall productivity reached 3.4 U/ml h, which was 18-fold of that in the batch culture.

  3. Batch calculations in CalcHEP

    International Nuclear Information System (INIS)

    Pukhov, A.

    2003-01-01

    CalcHEP is a clone of the CompHEP project which is developed by the author outside of the CompHEP group. CompHEP/CalcHEP are packages for automatic calculations of elementary particle decay and collision properties in the lowest order of perturbation theory. The main idea prescribed into the packages is to make available passing on from the Lagrangian to the final distributions effectively with a high level of automation. According to this, the packages were created as a menu driven user friendly programs for calculations in the interactive mode. From the other side, long-time calculations should be done in the non-interactive regime. Thus, from the beginning CompHEP has a problem of batch calculations. In CompHEP 33.23 the batch session was realized by mean of interactive menu which allows to the user to formulate the task for batch. After that the not-interactive session was launched. This way is too restricted, not flexible, and leads to doubling in programming. In this article I discuss another approach how one can force an interactive program to work in non-interactive mode. This approach was realized in CalcHEP 2.1 disposed on http://theory.sinp.msu.ru/~pukhov/calchep.html

  4. Pollution prevention applications in batch manufacturing operations

    Science.gov (United States)

    Sykes, Derek W.; O'Shaughnessy, James

    2004-02-01

    Older, "low-tech" batch manufacturing operations are often fertile grounds for gains resulting from pollution prevention techniques. This paper presents a pollution prevention technique utilized for wastewater discharge permit compliance purposes at a batch manufacturer of detergents, deodorants, and floor-care products. This manufacturer generated industrial wastewater as a result of equipment rinses required after each product batch changeover. After investing a significant amount of capital on end of pip-line wastewater treatment technology designed to address existing discharge limits, this manufacturer chose to investigate alternate, low-cost approaches to address anticipated new permit limits. Mass balances using spreadsheets and readily available formulation and production data were conducted on over 300 products to determine how each individual product contributed to the total wastewater pollutant load. These mass balances indicated that 22 products accounted for over 55% of the wastewater pollutant. Laboratory tests were conducted to determine whether these same products could accept their individual changeover rinse water as make-up water in formulations without sacrificing product quality. This changeover reuse technique was then implement at the plant scale for selected products. Significant reductions in wastewater volume (25%) and wastewater pollutant loading (85+%) were realized as a direct result of this approach.

  5. Batch-batch stable microbial community in the traditional fermentation process of huyumei broad bean pastes.

    Science.gov (United States)

    Zhu, Linjiang; Fan, Zihao; Kuai, Hui; Li, Qi

    2017-09-01

    During natural fermentation processes, a characteristic microbial community structure (MCS) is naturally formed, and it is interesting to know about its batch-batch stability. This issue was explored in a traditional semi-solid-state fermentation process of huyumei, a Chinese broad bean paste product. The results showed that this MCS mainly contained four aerobic Bacillus species (8 log CFU per g), including B. subtilis, B. amyloliquefaciens, B. methylotrophicus, and B. tequilensis, and the facultative anaerobe B. cereus with a low concentration (4 log CFU per g), besides a very small amount of the yeast Zygosaccharomyces rouxii (2 log CFU per g). The dynamic change of the MCS in the brine fermentation process showed that the abundance of dominant species varied within a small range, and in the beginning of process the growth of lactic acid bacteria was inhibited and Staphylococcus spp. lost its viability. Also, the MCS and its dynamic change were proved to be highly reproducible among seven batches of fermentation. Therefore, the MCS naturally and stably forms between different batches of the traditional semi-solid-state fermentation of huyumei. Revealing microbial community structure and its batch-batch stability is helpful for understanding the mechanisms of community formation and flavour production in a traditional fermentation. This issue in a traditional semi-solid-state fermentation of huyumei broad bean paste was firstly explored. This fermentation process was revealed to be dominated by a high concentration of four aerobic species of Bacillus, a low concentration of B. cereus and a small amount of Zygosaccharomyces rouxii. Lactic acid bacteria and Staphylococcus spp. lost its viability at the beginning of fermentation. Such the community structure was proved to be highly reproducible among seven batches. © 2017 The Society for Applied Microbiology.

  6. Repeat migration and disappointment.

    Science.gov (United States)

    Grant, E K; Vanderkamp, J

    1986-01-01

    This article investigates the determinants of repeat migration among the 44 regions of Canada, using information from a large micro-database which spans the period 1968 to 1971. The explanation of repeat migration probabilities is a difficult task, and this attempt is only partly successful. May of the explanatory variables are not significant, and the overall explanatory power of the equations is not high. In the area of personal characteristics, the variables related to age, sex, and marital status are generally significant and with expected signs. The distance variable has a strongly positive effect on onward move probabilities. Variables related to prior migration experience have an important impact that differs between return and onward probabilities. In particular, the occurrence of prior moves has a striking effect on the probability of onward migration. The variable representing disappointment, or relative success of the initial move, plays a significant role in explaining repeat migration probabilities. The disappointment variable represents the ratio of actural versus expected wage income in the year after the initial move, and its effect on both repeat migration probabilities is always negative and almost always highly significant. The repeat probabilities diminish after a year's stay in the destination region, but disappointment in the most recent year still has a bearing on the delayed repeat probabilities. While the quantitative impact of the disappointment variable is not large, it is difficult to draw comparisons since similar estimates are not available elsewhere.

  7. On-line Scheduling Of Multi-Server Batch Operations

    NARCIS (Netherlands)

    van der Zee, D.J.; van Harten, A.; Schuur, P.C.

    1999-01-01

    Batching jobs in a manufacturing system is a very common policy in most industries. Main reasons for batching are avoidance of setups and/or facilitation of material handling. Good examples of batch-wise production systems are ovens found in aircraft industry and in semiconductor manufacturing.

  8. On-line scheduling of multi-server batch operations

    NARCIS (Netherlands)

    Zee, Durk Jouke van der; Harten, Aart van; Schuur, Peter

    The batching of jobs in a manufacturing system is a very common policy in many industries. The main reasons for batching are the avoidance of setups and/or facilitation of material handling. Good examples of batch-wise production systems are the ovens that are found in the aircraft industry and in

  9. 7 CFR 58.728 - Cooking the batch.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Cooking the batch. 58.728 Section 58.728 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Procedures § 58.728 Cooking the batch. Each batch of cheese within the cooker, including the optional...

  10. 40 CFR 63.1408 - Aggregate batch vent stream provisions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Aggregate batch vent stream provisions... § 63.1408 Aggregate batch vent stream provisions. (a) Emission standards. Owners or operators of aggregate batch vent streams at a new or existing affected source shall comply with either paragraph (a)(1...

  11. BATCH-GE: Batch analysis of Next-Generation Sequencing data for genome editing assessment

    Science.gov (United States)

    Boel, Annekatrien; Steyaert, Woutert; De Rocker, Nina; Menten, Björn; Callewaert, Bert; De Paepe, Anne; Coucke, Paul; Willaert, Andy

    2016-01-01

    Targeted mutagenesis by the CRISPR/Cas9 system is currently revolutionizing genetics. The ease of this technique has enabled genome engineering in-vitro and in a range of model organisms and has pushed experimental dimensions to unprecedented proportions. Due to its tremendous progress in terms of speed, read length, throughput and cost, Next-Generation Sequencing (NGS) has been increasingly used for the analysis of CRISPR/Cas9 genome editing experiments. However, the current tools for genome editing assessment lack flexibility and fall short in the analysis of large amounts of NGS data. Therefore, we designed BATCH-GE, an easy-to-use bioinformatics tool for batch analysis of NGS-generated genome editing data, available from https://github.com/WouterSteyaert/BATCH-GE.git. BATCH-GE detects and reports indel mutations and other precise genome editing events and calculates the corresponding mutagenesis efficiencies for a large number of samples in parallel. Furthermore, this new tool provides flexibility by allowing the user to adapt a number of input variables. The performance of BATCH-GE was evaluated in two genome editing experiments, aiming to generate knock-out and knock-in zebrafish mutants. This tool will not only contribute to the evaluation of CRISPR/Cas9-based experiments, but will be of use in any genome editing experiment and has the ability to analyze data from every organism with a sequenced genome. PMID:27461955

  12. Bacteriocin Production with Lactobacillus amylovorus DCE 471 Is Improved and Stabilized by Fed-Batch Fermentation

    Science.gov (United States)

    Callewaert, Raf; De Vuyst, Luc

    2000-01-01

    Amylovorin L471 is a small, heat-stable, and hydrophobic bacteriocin produced by Lactobacillus amylovorus DCE 471. The nutritional requirements for amylovorin L471 production were studied with fed-batch fermentations. A twofold increase in bacteriocin titer was obtained when substrate addition was controlled by the acidification rate of the culture, compared with the titers reached with constant substrate addition or pH-controlled batch cultures carried out under the same conditions. An interesting feature of fed-batch cultures observed under certain culture conditions (constant feed rate) is the apparent stabilization of bacteriocin activity after obtaining maximum production. Finally, a mathematical model was set up to simulate cell growth, glucose and complex nitrogen source consumption, and lactic acid and bacteriocin production kinetics. The model showed that bacterial growth was dependent on both the energy and the complex nitrogen source. Bacteriocin production was growth associated, with a simultaneous bacteriocin adsorption on the producer cells dependent on the lactic acid accumulated and hence the viability of the cells. Both bacteriocin production and adsorption were inhibited by high concentrations of the complex nitrogen source. PMID:10653724

  13. Perfusion based cell culture chips

    DEFF Research Database (Denmark)

    Heiskanen, Arto; Emnéus, Jenny; Dufva, Martin

    2010-01-01

    Performing cell culture in miniaturized perfusion chambers gives possibilities to experiment with cells under near in vivo like conditions. In contrast to traditional batch cultures, miniaturized perfusion systems provide precise control of medium composition, long term unattended cultures...... and tissue like structuring of the cultures. However, as this chapter illustrates, many issues remain to be identified regarding perfusion cell culture such as design, material choice and how to use these systems before they will be widespread amongst biomedical researchers....

  14. Production of ethanol in batch and fed-batch fermentation of soluble sugar

    International Nuclear Information System (INIS)

    Chaudhary, M.Y.; Shah, M.A.; Shah, F.H.

    1991-01-01

    Keeping in view of the demand and need for alternate energy source, especially liquid fuels and the availability of raw materials in Pakistan, we have carried out biochemical and technological studies for ethanol through fermentation of renewable substrates. Molasses and sugar cane have been used as substrate for yeast fermentation. Selected yeast were used in both batch and semi continuous fermentation of molasses. Clarified dilute molasses were fermented with different strains of Saccharomyces cerevisiae. Ethanol concentration after 64 hours batch fermentation reached 9.4% with 90% yield based on sugar content. During feed batch system similar results were obtained after a fermentation cycle of 48 hours resulting in higher productivity. Similarly carbohydrates in fruit juices and hydro lysates of biomass can be economically fermented to ethanol to be used as feed stock for other chemicals. (author)

  15. Passing in Command Line Arguments and Parallel Cluster/Multicore Batching in R with batch.

    Science.gov (United States)

    Hoffmann, Thomas J

    2011-03-01

    It is often useful to rerun a command line R script with some slight change in the parameters used to run it - a new set of parameters for a simulation, a different dataset to process, etc. The R package batch provides a means to pass in multiple command line options, including vectors of values in the usual R format, easily into R. The same script can be setup to run things in parallel via different command line arguments. The R package batch also provides a means to simplify this parallel batching by allowing one to use R and an R-like syntax for arguments to spread a script across a cluster or local multicore/multiprocessor computer, with automated syntax for several popular cluster types. Finally it provides a means to aggregate the results together of multiple processes run on a cluster.

  16. Sojourn time distributions in a Markovian G-queue with batch arrival and batch removal

    Directory of Open Access Journals (Sweden)

    Yang Woo Shin

    1999-01-01

    Full Text Available We consider a single server Markovian queue with two types of customers; positive and negative, where positive customers arrive in batches and arrivals of negative customers remove positive customers in batches. Only positive customers form a queue and negative customers just reduce the system congestion by removing positive ones upon their arrivals. We derive the LSTs of sojourn time distributions for a single server Markovian queue with positive customers and negative customers by using the first passage time arguments for Markov chains.

  17. Cadmium removal using Cladophora in batch, semi-batch and flow reactors.

    Science.gov (United States)

    Sternberg, Steven P K; Dorn, Ryan W

    2002-02-01

    This study presents the results of using viable algae to remove cadmium from a synthetic wastewater. In batch and semi-batch tests, a local strain of Cladophora algae removed 80-94% of the cadmium introduced. The flow experiments that followed were conducted using non-local Cladophora parriaudii. Results showed that the alga removed only 12.7(+/-6.4)% of the cadmium introduced into the reactor. Limited removal was the result of insufficient algal quantities and poor contact between the algae and cadmium solution.

  18. The Pentapeptide Repeat Proteins

    OpenAIRE

    Vetting, Matthew W.; Hegde, Subray S.; Fajardo, J. Eduardo; Fiser, Andras; Roderick, Steven L.; Takiff, Howard E.; Blanchard, John S.

    2006-01-01

    The Pentapeptide Repeat Protein (PRP) family has over 500 members in the prokaryotic and eukaryotic kingdoms. These proteins are composed of, or contain domains composed of, tandemly repeated amino acid sequences with a consensus sequence of [S,T,A,V][D,N][L,F]-[S,T,R][G]. The biochemical function of the vast majority of PRP family members is unknown. The three-dimensional structure of the first member of the PRP family was determined for the fluoroquinolone resistance protein (MfpA) from Myc...

  19. Modeling and parameters identification of 2-keto-L-gulonic acid fed-batch fermentation.

    Science.gov (United States)

    Wang, Tao; Sun, Jibin; Yuan, Jingqi

    2015-04-01

    This article presents a modeling approach for industrial 2-keto-L-gulonic acid (2-KGA) fed-batch fermentation by the mixed culture of Ketogulonicigenium vulgare (K. vulgare) and Bacillus megaterium (B. megaterium). A macrokinetic model of K. vulgare is constructed based on the simplified metabolic pathways. The reaction rates obtained from the macrokinetic model are then coupled into a bioreactor model such that the relationship between substrate feeding rates and the main state variables, e.g., the concentrations of the biomass, substrate and product, is constructed. A differential evolution algorithm using the Lozi map as the random number generator is utilized to perform the model parameters identification, with the industrial data of 2-KGA fed-batch fermentation. Validation results demonstrate that the model simulations of substrate and product concentrations are well in coincidence with the measurements. Furthermore, the model simulations of biomass concentrations reflect principally the growth kinetics of the two microbes in the mixed culture.

  20. Repeated Causal Decision Making

    Science.gov (United States)

    Hagmayer, York; Meder, Bjorn

    2013-01-01

    Many of our decisions refer to actions that have a causal impact on the external environment. Such actions may not only allow for the mere learning of expected values or utilities but also for acquiring knowledge about the causal structure of our world. We used a repeated decision-making paradigm to examine what kind of knowledge people acquire in…

  1. simple sequence repeat (SSR)

    African Journals Online (AJOL)

    In the present study, 78 mapped simple sequence repeat (SSR) markers representing 11 linkage groups of adzuki bean were evaluated for transferability to mungbean and related Vigna spp. 41 markers amplified characteristic bands in at least one Vigna species. The transferability percentage across the genotypes ranged ...

  2. Telomerase Repeated Amplification Protocol (TRAP).

    Science.gov (United States)

    Mender, Ilgen; Shay, Jerry W

    2015-11-20

    Telomeres are found at the end of eukaryotic linear chromosomes, and proteins that bind to telomeres protect DNA from being recognized as double-strand breaks thus preventing end-to-end fusions (Griffith et al. , 1999). However, due to the end replication problem and other factors such as oxidative damage, the limited life span of cultured cells (Hayflick limit) results in progressive shortening of these protective structures (Hayflick and Moorhead, 1961; Olovnikov, 1973). The ribonucleoprotein enzyme complex telomerase-consisting of a protein catalytic component hTERT and a functional RNA component hTR or hTERC - counteracts telomere shortening by adding telomeric repeats to the end of chromosomes in ~90% of primary human tumors and in some transiently proliferating stem-like cells (Shay and Wright, 1996; Shay and Wright, 2001). This results in continuous proliferation of cells which is a hallmark of cancer. Therefore, telomere biology has a central role in aging, cancer progression/metastasis as well as targeted cancer therapies. There are commonly used methods in telomere biology such as Telomere Restriction Fragment (TRF) (Mender and Shay, 2015b), Telomere Repeat Amplification Protocol (TRAP) and Telomere dysfunction Induced Foci (TIF) analysis (Mender and Shay, 2015a). In this detailed protocol we describe Telomere Repeat Amplification Protocol (TRAP). The TRAP assay is a popular method to determine telomerase activity in mammalian cells and tissue samples (Kim et al. , 1994). The TRAP assay includes three steps: extension, amplification, and detection of telomerase products. In the extension step, telomeric repeats are added to the telomerase substrate (which is actually a non telomeric oligonucleotide, TS) by telomerase. In the amplification step, the extension products are amplified by the polymerase chain reaction (PCR) using specific primers (TS upstream primer and ACX downstream primer) and in the detection step, the presence or absence of telomerase is

  3. Silica-Supported Catalyst for Enantioselective Arylation of Aldehydes under Batch and Continuous-Flow Conditions.

    Science.gov (United States)

    Watanabe, Satoshi; Nakaya, Naoyuki; Akai, Junichiro; Kanaori, Kenji; Harada, Toshiro

    2018-05-04

    A silica-supported 3-aryl H 8 -BINOL-derived titanium catalyst exhibited high performance in the enantioselective arylation of aromatic aldehydes using Grignard and organolithium reagents not only under batch conditions but also under continuous-flow conditions. Even with a simple pipet reactor packed with the heterogeneous catalyst, the enantioselective production of chiral diarylmethanols could be achieved through a continuous introduction of aldehydes and mixed titanium reagents generated from the organometallic precursors. The pipet reactor could be used repeatedly in different reactions without appreciable deterioration of the activity.

  4. Evaluation of vitrification factors from DWPF's macro-batch 1

    International Nuclear Information System (INIS)

    Edwards, T.B.

    2000-01-01

    The Defense Waste Processing Facility (DWPF) is evaluating new sampling and analytical methods that may be used to support future Slurry Mix Evaporator (SME) batch acceptability decisions. This report uses data acquired during DWPF's processing of macro-batch 1 to determine a set of vitrification factors covering several SME and Melter Feed Tank (MFT) batches. Such values are needed for converting the cation measurements derived from the new methods to a ''glass'' basis. The available data from macro-batch 1 were used to examine the stability of these vitrification factors, to estimate their uncertainty over the course of a macro-batch, and to provide a recommendation on the use of a single factor for an entire macro-batch. The report is in response to Technical Task Request HLW/DWPF/TTR-980015

  5. Effects Of Heavy Metals On Growing Cultures Of Chlorella emersonii ...

    African Journals Online (AJOL)

    This work evaluates the effect of some metals on a green alga Chlorella emersonii, under continuous and batch culture conditions with added metal and another, batch culture with no added metal but where organism had been exposed to metal for 18 hours prior to growth. It was found that Chlorella growth under ...

  6. Inorganic fouling mitigation by salinity cycling in batch reverse osmosis

    OpenAIRE

    Maswadeh, Laith A.; Warsinger, David Elan Martin; Tow, Emily W.; Connors, Grace B.; Swaminathan, Jaichander; Lienhard, John H

    2018-01-01

    Enhanced fouling resistance has been observed in recent variants of reverse osmosis (RO) desalination which use time-varying batch or semi-batch processes, such as closed-circuit RO (CCRO) and pulse flow RO (PFRO). However, the mechanisms of batch processes' fouling resistance are not well-understood, and models have not been developed for prediction of their fouling performance. Here, a framework for predicting reverse osmosis fouling is developed by comparing the fluid residence time in bat...

  7. Optimizing Resource Utilization in Grid Batch Systems

    International Nuclear Information System (INIS)

    Gellrich, Andreas

    2012-01-01

    On Grid sites, the requirements of the computing tasks (jobs) to computing, storage, and network resources differ widely. For instance Monte Carlo production jobs are almost purely CPU-bound, whereas physics analysis jobs demand high data rates. In order to optimize the utilization of the compute node resources, jobs must be distributed intelligently over the nodes. Although the job resource requirements cannot be deduced directly, jobs are mapped to POSIX UID/GID according to the VO, VOMS group and role information contained in the VOMS proxy. The UID/GID then allows to distinguish jobs, if users are using VOMS proxies as planned by the VO management, e.g. ‘role=production’ for Monte Carlo jobs. It is possible to setup and configure batch systems (queuing system and scheduler) at Grid sites based on these considerations although scaling limits were observed with the scheduler MAUI. In tests these limitations could be overcome with a home-made scheduler.

  8. Sewage sludge irradiators: Batch and continuous flow

    International Nuclear Information System (INIS)

    Lavale, D.S.; George, J.R.; Shah, M.R.; Rawat, K.P.

    1998-01-01

    The potential threat to the environment imposed by high pathogenic organism content in municipal wastewater, especially the sludge and the world-wide growing aspirations for a cleaner, salubrious environment have made it mandatory for the sewage and sludge to undergo treatment, prior to their ultimate disposal to mother nature. Incapabilities associated with the conventional wastewater treatments to mitigate the problem of microorganisms have made it necessary to look for other alternatives, radiation treatment being the most reliable, rapid and environmentally sustainable of them. To promote the use of radiation for the sludge hygienization, Department of Atomic Energy has endeavoured to set up an indigenous, Sludge Hygienization Research Irradiator (SHRI) in the city of Baroda. Designed for 18.5 PBq of 60 Co to disinfect the digested sludge, the irradiator has additional provision for treatment of effluent and raw sewage. From engineering standpoint, all the subsystems have been functioning satisfactorily since its commissioning in 1990. Prolonged studies, spanning over a period of six years, primarily focused on inactivation of microorganism revealed that 3 kGy dose of gamma radiation is adequate to make the sludge pathogen and odour-free. A dose of 1.6 kGy in raw sewage and 0.5 kGy in effluent reduced coliform counts down to the regulatory discharge limits. These observations reflect a possible cost-effective solution to the burgeoning problem of surface water pollution across the globe. In the past, sub 37 PBq 60 Co batch irradiators have been designed and commissioned successfully for the treatment of sludge. Characterized with low dose delivery rates they are well-suited for treating low volumes of sludge in batches. Some concepts of continuous flow 60 Co irradiators having larger activities, yet simple and economic in design, are presented in the paper

  9. Production of Medium-Chain-Length Poly(3-Hydroxyalkanoates from Saponified Palm Kernel Oil by Pseudomonas putida: Kinetics of Batch and Fed-Batch Fermentations

    Directory of Open Access Journals (Sweden)

    Annuar, M. S. M.

    2006-01-01

    Full Text Available The kinetics of medium-chain-length poly(3-hydroxyalkanoates, PHAMCL production by Pseudomonas putida PGA1 in batch and fed-batch fermentations were studied. With saponified palm kernel oil (SPKO supplying the free fatty acids mixture as the sole carbon and energy source, PHAMCL accumulation is encouraged under ammonium-limited condition, which is a nitrogen stress environment. The amount of PHAMCL accumulated and its specific production rate, qPHA were influenced by the residual ammonium concentration level in the culture medium. It was observed that in both fermentation modes, when the residual ammonium was exhausted (< 0.05 gL-1, the PHAMCL accumulation (11.9% and qPHA (0.0062 h-1 were significantly reduced. However, this effect can be reversed by feeding low amount of ammonium to the culture, resulting in significantly improved PHAMCL yield (71.4% and specific productivity (0.6 h-1. It is concluded that the feeding of low ammonium concentration to the culture medium during the PHAMCL accumulation has a positive effect on sustaining the PHAMCL biosynthetic capability of the organism. It was also found that increasing SPKO concentration in the medium significantly reduced (up to 50% the volumetric oxygen transfer coefficient (KLa of the fermentation system.

  10. Expression of a mutated SPT15 gene in Saccharomyces cerevisiae enhances both cell growth and ethanol production in microaerobic batch, fed-batch, and simultaneous saccharification and fermentations.

    Science.gov (United States)

    Seong, Yeong-Je; Park, Haeseong; Yang, Jungwoo; Kim, Soo-Jung; Choi, Wonja; Kim, Kyoung Heon; Park, Yong-Cheol

    2017-05-01

    The SPT15 gene encodes a Saccharomyces cerevisiae TATA-binding protein, which is able to globally control the transcription levels of various metabolic and regulatory genes. In this study, a SPT15 gene mutant (S42N, S78R, S163P, and I212N) was expressed in S. cerevisiae BY4741 (BSPT15-M3), of which effects on fermentative yeast properties were evaluated in a series of culture types. By applying different nitrogen sources and air supply conditions in batch culture, organic nitrogen sources and microaerobic condition were decided to be more favorable for both cell growth and ethanol production of the BSPT15-M3 strain than the control S. cerevisiae BY4741 strain expressing the SPT15 gene (BSPT15wt). Microaerobic fed-batch cultures of BSPT15-M3 with glucose shock in the presence of high ethanol content resulted in a 9.5-13.4% higher glucose consumption rate and ethanol productivity than those for the BSPT15wt strain. In addition, BSPT15-M3 showed 4.5 and 3.9% increases in ethanol productivity from cassava hydrolysates and corn starch in simultaneous saccharification and fermentation processes, respectively. It was concluded that overexpression of the mutated SPT15 gene would be a potent strategy to develop robust S. cerevisiae strains with enhanced cell growth and ethanol production abilities.

  11. Bioprocess iterative batch-to-batch optimization based on hybrid parametric/nonparametric models.

    Science.gov (United States)

    Teixeira, Ana P; Clemente, João J; Cunha, António E; Carrondo, Manuel J T; Oliveira, Rui

    2006-01-01

    This paper presents a novel method for iterative batch-to-batch dynamic optimization of bioprocesses. The relationship between process performance and control inputs is established by means of hybrid grey-box models combining parametric and nonparametric structures. The bioreactor dynamics are defined by material balance equations, whereas the cell population subsystem is represented by an adjustable mixture of nonparametric and parametric models. Thus optimizations are possible without detailed mechanistic knowledge concerning the biological system. A clustering technique is used to supervise the reliability of the nonparametric subsystem during the optimization. Whenever the nonparametric outputs are unreliable, the objective function is penalized. The technique was evaluated with three simulation case studies. The overall results suggest that the convergence to the optimal process performance may be achieved after a small number of batches. The model unreliability risk constraint along with sampling scheduling are crucial to minimize the experimental effort required to attain a given process performance. In general terms, it may be concluded that the proposed method broadens the application of the hybrid parametric/nonparametric modeling technique to "newer" processes with higher potential for optimization.

  12. Modelling and Simulation of the Batch Hydrolysis of Acetic ...

    African Journals Online (AJOL)

    The kinetic modelling of the batch synthesis of acetic acid from acetic anhydride was investigated. The kinetic data of the reaction was obtained by conducting the hydrolysis reaction in a batch reactor. A dynamic model was formulated for this process and simulation was carried out using gPROMS® an advanced process ...

  13. [Batch release of immunoglobulin and monoclonal antibody products].

    Science.gov (United States)

    Gross, S

    2014-10-01

    The Paul-Ehrlich Institute (PEI) is an independent institution of the Federal Republic of Germany responsible for performing official experimental batch testing of sera. The institute decides about the release of each batch and performs experimental research in the field. The experimental quality control ensures the potency of the product and also the absence of harmful impurities. For release of an immunoglobulin batch the marketing authorization holder has to submit the documentation of the manufacture and the results of quality control measures together with samples of the batch to the PEI. Experimental testing is performed according to the approved specifications regarding the efficacy and safety. Since implementation of the 15th German drug law amendment, the source of antibody is not defined anymore. According to § 32 German drug law, all batches of sera need to be released by an official control laboratory. Sera are medicinal products, which contain antibodies, antibody fragments or fusion proteins with a functional antibody portion. Therefore, all batches of monoclonal antibodies and derivatives must also be released by the PEI and the marketing authorization holder has to submit a batch release application. Under certain circumstances a waiver for certain products can be issued with regard to batch release. The conditions for such a waiver apply to the majority of monoclonal antibodies.

  14. 21 CFR 80.37 - Treatment of batch pending certification.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Treatment of batch pending certification. 80.37 Section 80.37 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL COLOR ADDITIVE CERTIFICATION Certification Procedures § 80.37 Treatment of batch pending certification...

  15. Solving a chemical batch scheduling problem by local search

    NARCIS (Netherlands)

    Brucker, P.; Hurink, Johann L.

    1999-01-01

    A chemical batch scheduling problem is modelled in two different ways as a discrete optimization problem. Both models are used to solve the batch scheduling problem in a two-phase tabu search procedure. The method is tested on real-world data.

  16. Dynamic Scheduling Of Batch Operations With Non-Identical Machines

    NARCIS (Netherlands)

    van der Zee, D.J.; van Harten, A.; Schuur, P.C.

    1997-01-01

    Batch-wise production is found in many industries. A good example of production systems which process products batch-wise are the ovens found in aircraft industry and in semiconductor manufacturing. These systems mostly consist of multiple machines of different types, given the range and volumes of

  17. Dynamic scheduling of batch operations with non-identical machines

    NARCIS (Netherlands)

    van der Zee, D.J.; van Harten, Aart; Schuur, Peter

    1997-01-01

    Batch-wise production is found in many industries. A good example of production systems which process products batch-wise are the ovens found in aircraft industry and in semiconductor manufacturing. These systems mostly consist of multiple machines of different types, given the range and volumes of

  18. Repeatability of Cryogenic Multilayer Insulation

    Science.gov (United States)

    Johnson, W. L.; Vanderlaan, M.; Wood, J. J.; Rhys, N. O.; Guo, W.; Van Sciver, S.; Chato, D. J.

    2017-12-01

    Due to the variety of requirements across aerospace platforms, and one off projects, the repeatability of cryogenic multilayer insulation (MLI) has never been fully established. The objective of this test program is to provide a more basic understanding of the thermal performance repeatability of MLI systems that are applicable to large scale tanks. There are several different types of repeatability that can be accounted for: these include repeatability between identical blankets, repeatability of installation of the same blanket, and repeatability of a test apparatus. The focus of the work in this report is on the first two types of repeatability. Statistically, repeatability can mean many different things. In simplest form, it refers to the range of performance that a population exhibits and the average of the population. However, as more and more identical components are made (i.e. the population of concern grows), the simple range morphs into a standard deviation from an average performance. Initial repeatability testing on MLI blankets has been completed at Florida State University. Repeatability of five Glenn Research Center (GRC) provided coupons with 25 layers was shown to be +/- 8.4% whereas repeatability of repeatedly installing a single coupon was shown to be +/- 8.0%. A second group of 10 coupons has been fabricated by Yetispace and tested by Florida State University, the repeatability between coupons has been shown to be +/- 15-25%. Based on detailed statistical analysis, the data has been shown to be statistically significant.

  19. A canned food scheduling problem with batch due date

    Science.gov (United States)

    Chung, Tsui-Ping; Liao, Ching-Jong; Smith, Milton

    2014-09-01

    This article considers a canned food scheduling problem where jobs are grouped into several batches. Jobs can be sent to the next operation only when all the jobs in the same batch have finished their processing, i.e. jobs in a batch, have a common due date. This batch due date problem is quite common in canned food factories, but there is no efficient heuristic to solve the problem. The problem can be formulated as an identical parallel machine problem with batch due date to minimize the total tardiness. Since the problem is NP hard, two heuristics are proposed to find the near-optimal solution. Computational results comparing the effectiveness and efficiency of the two proposed heuristics with an existing heuristic are reported and discussed.

  20. Spatial and interannual variability in Baltic sprat batch fecundity

    DEFF Research Database (Denmark)

    Haslob, H.; Tomkiewicz, Jonna; Hinrichsen, H.H.

    2011-01-01

    in the central Baltic Sea, namely the Bornholm Basin, Gdansk Deep and Southern Gotland Basin. Environmental parameters such as hydrography, fish condition and stock density were tested in order to investigate the observed variability in sprat fecundity. Absolute batch fecundity was found to be positively related...... to fish length and weight. Significant differences in absolute and relative batch fecundity of Baltic sprat among areas and years were detected, and could partly be explained by hydrographic features of the investigated areas. A non-linear multiple regression model taking into account fish length...... and ambient temperature explained 70% of variability in absolute batch fecundity. Oxygen content and fish condition were not related to sprat batch fecundity. Additionally, a negative effect of stock size on sprat batch fecundity in the Bornholm Basin was revealed. The obtained data and results are important...

  1. Biodenitrification in Sequencing Batch Reactors. Final report

    International Nuclear Information System (INIS)

    Silverstein, J.

    1996-01-01

    One plan for stabilization of the Solar Pond waters and sludges at Rocky Flats Plant (RFP), is evaporation and cement solidification of the salts to stabilize heavy metals and radionuclides for land disposal as low-level mixed waste. It has been reported that nitrate (NO 3- ) salts may interfere with cement stabilization of heavy metals and radionuclides. Therefore, biological nitrate removal (denitrification) may be an important pretreatment for the Solar Pond wastewaters at RFP, improving the stability of the cement final waste form, reducing the requirement for cement (or pozzolan) additives and reducing the volume of cemented low-level mixed waste requiring ultimate disposal. A laboratory investigation of the performance of the Sequencing Batch Reactor (SBR) activated sludge process developed for nitrate removal from a synthetic brine typical of the high-nitrate and high-salinity wastewaters in the Solar Ponds at Rocky Flats Plant was carried out at the Environmental Engineering labs at the University of Colorado, Boulder, between May 1, 1994 and October 1, 1995

  2. Glucoamylase production in batch, chemostat and fed-batch cultivations by an industrial strain of Aspergillus niger

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Beyer, Michael; Nielsen, Jens

    2000-01-01

    The Aspergillus niger strain BO-1 was grown in batch, continuous (chemostat) and fed-batch cultivations in order to study the production of the extracellular enzyme glucoamylase under different growth conditions. In the pH range 2.5-6.0, the specific glucoamylase productivity and the specific...

  3. Batch-to-batch quality consistency evaluation of botanical drug products using multivariate statistical analysis of the chromatographic fingerprint.

    Science.gov (United States)

    Xiong, Haoshu; Yu, Lawrence X; Qu, Haibin

    2013-06-01

    Botanical drug products have batch-to-batch quality variability due to botanical raw materials and the current manufacturing process. The rational evaluation and control of product quality consistency are essential to ensure the efficacy and safety. Chromatographic fingerprinting is an important and widely used tool to characterize the chemical composition of botanical drug products. Multivariate statistical analysis has showed its efficacy and applicability in the quality evaluation of many kinds of industrial products. In this paper, the combined use of multivariate statistical analysis and chromatographic fingerprinting is presented here to evaluate batch-to-batch quality consistency of botanical drug products. A typical botanical drug product in China, Shenmai injection, was selected as the example to demonstrate the feasibility of this approach. The high-performance liquid chromatographic fingerprint data of historical batches were collected from a traditional Chinese medicine manufacturing factory. Characteristic peaks were weighted by their variability among production batches. A principal component analysis model was established after outliers were modified or removed. Multivariate (Hotelling T(2) and DModX) control charts were finally successfully applied to evaluate the quality consistency. The results suggest useful applications for a combination of multivariate statistical analysis with chromatographic fingerprinting in batch-to-batch quality consistency evaluation for the manufacture of botanical drug products.

  4. Batch-To-Batch Rational Feedforward Control : From Iterative Learning to Identification Approaches, with Application to a Wafer Stage

    NARCIS (Netherlands)

    Blanken, L.; Boeren, F.A.J.; Bruijnen, D.J.H.; Oomen, T.A.E.

    2017-01-01

    Feedforward control enables high performance for industrial motion systems that perform nonrepeating motion tasks. Recently, learning techniques have been proposed that improve both performance and flexibility to nonrepeating tasks in a batch-To-batch fashion by using a rational parameterization in

  5. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    Directory of Open Access Journals (Sweden)

    Gupta Rishi

    2012-03-01

    Full Text Available Abstract Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydrolysis was carried out at elevated solid loading up to 20% (w/v and a comparison kinetics of batch and fed-batch enzymatic hydrolysis was carried out using kinetic regimes. Under batch mode, the actual sugar concentration values at 20% initial substrate consistency were found deviated from the predicted values and the maximum sugar concentration obtained was 80.78 g/L. Fed-batch strategy was implemented to enhance the final sugar concentration to 127 g/L. The batch and fed-batch enzymatic hydrolysates were fermented with Saccharomyces cerevisiae and ethanol production of 34.78 g/L and 52.83 g/L, respectively, were achieved. Furthermore, model simulations showed that higher insoluble solids in the feed resulted in both smaller reactor volume and shorter residence time. Conclusion Fed-batch enzymatic hydrolysis is an efficient procedure for enhancing the sugar concentration in the hydrolysate. Restricting the process to suitable kinetic regimes could result in higher conversion rates.

  6. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    Science.gov (United States)

    2012-01-01

    Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydrolysis was carried out at elevated solid loading up to 20% (w/v) and a comparison kinetics of batch and fed-batch enzymatic hydrolysis was carried out using kinetic regimes. Under batch mode, the actual sugar concentration values at 20% initial substrate consistency were found deviated from the predicted values and the maximum sugar concentration obtained was 80.78 g/L. Fed-batch strategy was implemented to enhance the final sugar concentration to 127 g/L. The batch and fed-batch enzymatic hydrolysates were fermented with Saccharomyces cerevisiae and ethanol production of 34.78 g/L and 52.83 g/L, respectively, were achieved. Furthermore, model simulations showed that higher insoluble solids in the feed resulted in both smaller reactor volume and shorter residence time. Conclusion Fed-batch enzymatic hydrolysis is an efficient procedure for enhancing the sugar concentration in the hydrolysate. Restricting the process to suitable kinetic regimes could result in higher conversion rates. PMID:22433563

  7. Repeat Customer Success in Extension

    Science.gov (United States)

    Bess, Melissa M.; Traub, Sarah M.

    2013-01-01

    Four multi-session research-based programs were offered by two Extension specialist in one rural Missouri county. Eleven participants who came to multiple Extension programs could be called "repeat customers." Based on the total number of participants for all four programs, 25% could be deemed as repeat customers. Repeat customers had…

  8. 78 FR 65594 - Vehicular Repeaters

    Science.gov (United States)

    2013-11-01

    ... coordinators estimate the effect on coordination fees? Does the supposed benefit that mobile repeater stations... allow the licensing and operation of vehicular repeater systems and other mobile repeaters by public... email: [email protected] or phone: 202-418- 0530 or TTY: 202-418-0432. For detailed instructions for...

  9. Repeated causal decision making.

    Science.gov (United States)

    Hagmayer, York; Meder, Björn

    2013-01-01

    Many of our decisions refer to actions that have a causal impact on the external environment. Such actions may not only allow for the mere learning of expected values or utilities but also for acquiring knowledge about the causal structure of our world. We used a repeated decision-making paradigm to examine what kind of knowledge people acquire in such situations and how they use their knowledge to adapt to changes in the decision context. Our studies show that decision makers' behavior is strongly contingent on their causal beliefs and that people exploit their causal knowledge to assess the consequences of changes in the decision problem. A high consistency between hypotheses about causal structure, causally expected values, and actual choices was observed. The experiments show that (a) existing causal hypotheses guide the interpretation of decision feedback, (b) consequences of decisions are used to revise existing causal beliefs, and (c) decision makers use the experienced feedback to induce a causal model of the choice situation even when they have no initial causal hypotheses, which (d) enables them to adapt their choices to changes of the decision problem. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  10. Capacity Planning for Batch and Perfusion Bioprocesses Across Multiple Biopharmaceutical Facilities

    Science.gov (United States)

    Siganporia, Cyrus C; Ghosh, Soumitra; Daszkowski, Thomas; Papageorgiou, Lazaros G; Farid, Suzanne S

    2014-01-01

    Production planning for biopharmaceutical portfolios becomes more complex when products switch between fed-batch and continuous perfusion culture processes. This article describes the development of a discrete-time mixed integer linear programming (MILP) model to optimize capacity plans for multiple biopharmaceutical products, with either batch or perfusion bioprocesses, across multiple facilities to meet quarterly demands. The model comprised specific features to account for products with fed-batch or perfusion culture processes such as sequence-dependent changeover times, continuous culture constraints, and decoupled upstream and downstream operations that permit independent scheduling of each. Strategic inventory levels were accounted for by applying cost penalties when they were not met. A rolling time horizon methodology was utilized in conjunction with the MILP model and was shown to obtain solutions with greater optimality in less computational time than the full-scale model. The model was applied to an industrial case study to illustrate how the framework aids decisions regarding outsourcing capacity to third party manufacturers or building new facilities. The impact of variations on key parameters such as demand or titres on the optimal production plans and costs was captured. The analysis identified the critical ratio of in-house to contract manufacturing organization (CMO) manufacturing costs that led the optimization results to favor building a future facility over using a CMO. The tool predicted that if titres were higher than expected then the optimal solution would allocate more production to in-house facilities, where manufacturing costs were lower. Utilization graphs indicated when capacity expansion should be considered. © 2013 The Authors Biotechnology Progress published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers Biotechnol. Prog., 30:594–606, 2014 PMID:24376262

  11. Capacity planning for batch and perfusion bioprocesses across multiple biopharmaceutical facilities.

    Science.gov (United States)

    Siganporia, Cyrus C; Ghosh, Soumitra; Daszkowski, Thomas; Papageorgiou, Lazaros G; Farid, Suzanne S

    2014-01-01

    Production planning for biopharmaceutical portfolios becomes more complex when products switch between fed-batch and continuous perfusion culture processes. This article describes the development of a discrete-time mixed integer linear programming (MILP) model to optimize capacity plans for multiple biopharmaceutical products, with either batch or perfusion bioprocesses, across multiple facilities to meet quarterly demands. The model comprised specific features to account for products with fed-batch or perfusion culture processes such as sequence-dependent changeover times, continuous culture constraints, and decoupled upstream and downstream operations that permit independent scheduling of each. Strategic inventory levels were accounted for by applying cost penalties when they were not met. A rolling time horizon methodology was utilized in conjunction with the MILP model and was shown to obtain solutions with greater optimality in less computational time than the full-scale model. The model was applied to an industrial case study to illustrate how the framework aids decisions regarding outsourcing capacity to third party manufacturers or building new facilities. The impact of variations on key parameters such as demand or titres on the optimal production plans and costs was captured. The analysis identified the critical ratio of in-house to contract manufacturing organization (CMO) manufacturing costs that led the optimization results to favor building a future facility over using a CMO. The tool predicted that if titres were higher than expected then the optimal solution would allocate more production to in-house facilities, where manufacturing costs were lower. Utilization graphs indicated when capacity expansion should be considered. © 2014 The Authors Biotechnology Progress published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers.

  12. Ethanol production potential from fermented rice noodle wastewater treatment using entrapped yeast cell sequencing batch reactor

    Science.gov (United States)

    Siripattanakul-Ratpukdi, Sumana

    2012-03-01

    Fermented rice noodle production generates a large volume of starch-based wastewater. This study investigated the treatment of the fermented rice noodle wastewater using entrapped cell sequencing batch reactor (ECSBR) compared to traditional sequencing batch reactor (SBR). The yeast cells were applied because of their potential to convert reducing sugar in the wastewater to ethanol. In present study, preliminary treatment by acid hydrolysis was performed. A yeast culture, Saccharomyces cerevisiae, with calcium alginate cell entrapment was used. Optimum yeast cell loading in batch experiment and fermented rice noodle treatment performances using ECSBR and SBR systems were examined. In the first part, it was found that the cell loadings (0.6-2.7 × 108 cells/mL) did not play an important role in this study. Treatment reactions followed the second-order kinetics with the treatment efficiencies of 92-95%. In the second part, the result showed that ECSBR performed better than SBR in both treatment efficiency and system stability perspectives. ECSBR maintained glucose removal of 82.5 ± 10% for 5-cycle treatment while glucose removal by SBR declined from 96 to 40% within the 5-cycle treatment. Scanning electron microscopic images supported the treatment results. A number of yeast cells entrapped and attached onto the matrix grew in the entrapment matrix.

  13. Batch experiment on H2S degradation by bacteria immobilised on activated carbons.

    Science.gov (United States)

    Yan, R; Ng, Y L; Chen, X G; Geng, A L; Gould, W D; Duan, H Q; Liang, D T; Koe, L C C

    2004-01-01

    Biological treatments of odorous compounds, as compared to chemical or physical technologies, are in general ecologically and environmentally favourable. However, there are some inefficiencies relative to the media used in biofiltration processes, such as the need for an adequate residence time; the limited lifetime, and pore blockage of media, which at present render the technology economically non-viable. The aim of the study is to develop novel active media to be used in performance-enhanced biofiltration processes, by achieving an optimum balance and combination of the media adsorption capacity with the biodegradation of H2S through the bacteria immobilised on the media. An enrichment culture was obtained from activated sludges in order to metabolise thiosulphate. Batch-wise experiments were conducted to optimise the bacteria immobilisation on activated carbon, so as to develop a novel "biocarbon". Biofilm was mostly developed through culturing the bacteria with the presence of carbons in mineral media. SEM and BET tests of the carbon along with the culturing process were used to identify, respectively, the biofilm development and biocarbon porosity. Breakthrough tests evaluated the biocarbon performance with varying gas resistance time, inlet H2S concentration, and type of support materials. Fundamental issues were discussed, including type of support material, mode of bacteria immobilisation, pore blockages, and biodegradation kinetics, etc. This batch-wise study provides a basis for our future research on optimisation of the biofiltration process using a bio-trickling reactor.

  14. Comparative study on major bioactive components in natural, artificial and in-vitro cultured Calculus Bovis.

    Science.gov (United States)

    Yan, Shi-Kai; Wu, Yan-Wen; Liu, Run-Hui; Zhang, Wei-Dong

    2007-01-01

    Major bioactive components in various Calculus Bovis, including natural, artificial and in-vitro cultured Calculus Bovis, were comparatively studied. An approach of high-performance liquid chromatography coupled with ultraviolet and evaporative light scattering detections (HPLC/UV/ELSD) was established to simultaneously determinate six bioactive components thereof, including five bile acids (cholic acid, deoxycholic acid, ursodeoxycholic, chenodeoxycholic acid, hyodeoxycholic acid) and bilirubin. ELSD and UV detector were applied to detect bile acids and bilirubin respectively. The assay was performed on a C(18) column with water-acetonitrile gradient elution and the investigated constituents were authenticated by comparing retention times and mass spectra with those of reference compounds. The proposed method was applied to analyze twenty-one Calculus Bovis extraction samples, and produced data with acceptable linearity, precision, repeatability and accuracy. The result indicated the variations among Calculus Bovis samples under different developmental conditions. Artificial and in-vitro cultured Calculus Bovis, especially in-vitro cultured ones, which contain total bioactive constituents no less than natural products and have the best batch-to-batch uniformity, suffice to be used as substitutes of natural Calculus Bovis.

  15. Long-term, repeated dose in vitro neurotoxicity of the glutamate receptor antagonist L-AP3, demonstrated in rat hippocampal slice cultures by using continuous propidium iodide incubation.

    Science.gov (United States)

    Kristensen, Bjarne W; Blaabjerg, Morten; Noraberg, Jens; Zimmer, Jens

    2007-05-01

    Most in vitro models are only used to assess short-term effects of test compounds. However, as demonstrated here, hippocampal slice cultures can be used for long-term studies. The test compound used was the metabotropic glutamate receptor antagonist, L(+)-2-amino-3-phosphonopropionic acid (L-AP3), which is known to be toxic in vivo after subchronic, but not acute, administration. Degenerative effects were monitored by measuring the cellular uptake of propidium iodide (PI; continuously present in the medium) and lactate dehydrogenase (LDH) leakage, and by using a panel of histological stains. Hippocampal slices, derived from 2-3 day old rats and grown for 3 weeks, were subsequently exposed for the next 3 weeks to 0, 10 or 100microM L-AP3, with PI (2microM) in the culture medium. Exposure to 100microM L-AP3 induced severe toxicity after 4-6 days, shown by massive PI uptake, LDH leakage, changes in MAP2 and GFAP immunostaining, and in Nissl and Timm staining. In contrast, 10microM L-AP3 did not induce detectable neuronal degeneration. Treatment with the NMDA receptor antagonist, MK-801, or the AMPA/KA receptor antagonist NBQX, together with 100microM L-AP3, reduced neurodegeneration down to close to control values. It is concluded that continuous incubation of hippocampal slice cultures with PI is technically feasible for use in studies of inducible neuronal degeneration over time.

  16. Batched Triangular DLA for Very Small Matrices on GPUs

    KAUST Repository

    Charara, Ali; Keyes, David E.; Ltaief, Hatem

    2017-01-01

    linear algebra operations on very small matrix sizes (usually less than 100). Batched dense linear algebra kernels are becoming ubiquitous for such scientific computations. Within a single API call, these kernels are capable of simultaneously launching a

  17. Groundwater arsenic remediation using zerovalent iron: Batch and column tests

    Science.gov (United States)

    Recently, increasing efforts have been made to explore the applicability and limitations of zerovalent iron (Fe0) for the treatment of arsenicbearing groundwater and wastewater. The experimental batch and column tests have demonstrated that arsenate and arsenite are removed effec...

  18. Batch Adsorption Study of Methylene Blue in Aqueous Solution ...

    African Journals Online (AJOL)

    PROF HORSFALL

    of methylene blue (azo dye) from the synthetic industrial wastewater was investigated in a batch system. Rice husk and coconut shell were ... the textiles, rubber, paper, plastics, cosmetic, and .... wastewater by. Fenton's oxidation: Kinetic study.

  19. Automated batch emulsion copolymerization of styrene and butyl acrylate

    NARCIS (Netherlands)

    Mballa Mballa, M.A.; Schubert, U.S.; Heuts, J.P.A.; Herk, van A.M.

    2011-01-01

    This article describes a method for carrying out emulsion copolymerization using an automated synthesizer. For this purpose, batch emulsion copolymerizations of styrene and butyl acrylate were investigated. The optimization of the polymerization system required tuning the liquid transfer method,

  20. development of an automated batch-process solar water disinfection

    African Journals Online (AJOL)

    user

    This work presents the development of an automated batch-process water disinfection system ... Locally sourced materials in addition to an Arduinomicro processor were used to control ..... As already mentioned in section 3.1.1, a statistical.

  1. Numerical modeling of batch formation in waste incineration plants

    Directory of Open Access Journals (Sweden)

    Obroučka Karel

    2015-03-01

    Full Text Available The aim of this paper is a mathematical description of algorithm for controlled assembly of incinerated batch of waste. The basis for formation of batch is selected parameters of incinerated waste as its calorific value or content of pollutants or the combination of both. The numerical model will allow, based on selected criteria, to compile batch of wastes which continuously follows the previous batch, which is a prerequisite for optimized operation of incinerator. The model was prepared as for waste storage in containers, as well as for waste storage in continuously refilled boxes. The mathematical model was developed into the computer program and its functionality was verified either by practical measurements or by numerical simulations. The proposed model can be used in incinerators for hazardous and municipal waste.

  2. 40 CFR 63.462 - Batch cold cleaning machine standards.

    Science.gov (United States)

    2010-07-01

    .... (a) Each owner or operator of an immersion batch cold solvent cleaning machine shall comply with the... cleaning machine complying with paragraph (a)(2) or (b) of this section shall comply with the work and...

  3. Optimal Control of a Fed-Batch Fermentation Involving Multiple Feeds

    Directory of Open Access Journals (Sweden)

    Chongyang Liu

    2012-01-01

    Full Text Available A nonlinear dynamical system, in which the feed rates of glycerol and alkali are taken as the control functions, is first proposed to formulate the fed-batch culture of 1,3-propanediol (1,3-PD production. To maximize the 1,3-PD concentration at the terminal time, a constrained optimal control model is then presented. A solution approach is developed to seek the optimal feed rates based on control vector parametrization method and improved differential evolution algorithm. The proposed methodology yielded an increase by 32.17% of 1,3-PD concentration at the terminal time.

  4. Batch phenol biodegradation study and application of factorial experimental design

    Directory of Open Access Journals (Sweden)

    A. Hellal

    2010-01-01

    Full Text Available A bacterium, Pseudomonas aeruginosa (ATTC27853, was investigated for its ability to grow and to degrade phenol as solecarbon source, in aerobic batch culture. The parameters which affect the substrate biodegradation such as the adaptation ofbacteria to phenol, the temperature, and the nature of the bacteria were investigated. The results show that for a range oftemperature of 30 to 40°C, the best degradation of phenol for a concentration of 100mg/l was observed at 30°C. The regenerationof the bacterium which allows the reactivation of its enzymatic activity, shows that the degradation of 100 mg/ l ofsubstrate at 30° C required approximately 50 hours with revivified bacteria, while it only starts after 72 hours for those norevivified. Adapted to increasing concentrations, allows the bacteria to degrade a substrate concentration of about 400mg/l in less than 350 hours.A second part was consisted in the determination of a substrate degradation model using the factorial experiment design,as a function of temperature (30-40°C and of the size of the inoculums (260.88 - 521.76mg/ l. The results were analyzedstatistically using the Student’s t-test, analysis of variance, and F-test. The value of R2 (0.99872 and adjusted R2 (0.9962close to 1.0, verifies the good correlation between the observed and the predicted values, and provides the excellent relationshipbetween the independent variables (factors and the response (the time of the phenol degradation. F-value found above200, indicates that the considered model is statistically significant.

  5. Dynamic Extensions of Batch Systems with Cloud Resources

    International Nuclear Information System (INIS)

    Hauth, T; Quast, G; Büge, V; Scheurer, A; Kunze, M; Baun, C

    2011-01-01

    Compute clusters use Portable Batch Systems (PBS) to distribute workload among individual cluster machines. To extend standard batch systems to Cloud infrastructures, a new service monitors the number of queued jobs and keeps track of the price of available resources. This meta-scheduler dynamically adapts the number of Cloud worker nodes according to the requirement profile. Two different worker node topologies are presented and tested on the Amazon EC2 Cloud service.

  6. Effect of glass-batch makeup on the melting process

    International Nuclear Information System (INIS)

    Hrma, Pavel R.; Schweiger, Michael J.; Humrickhouse, Carissa J.; Moody, J. Adam; Tate, Rachel M.; Rainsdon, Timothy T.; Tegrotenhuis, Nathan E.; Arrigoni, Benjamin M.; Marcial, Jose; Rodriguez, Carmen P.; Tincher, Benjamin

    2010-01-01

    The response of a glass batch to heating is determined by the batch makeup and in turn determines the rate of melting. Batches formulated for a high-alumina nuclear waste to be vitrified in an all-electric melter were heated at a constant temperature-increase rate to determine changes in melting behavior in response to the selection of batch chemicals and silica grain-size as well as the addition of heat-generating reactants. The type of batch materials and the size of silica grains determine how much, if any, primary foam occurs during melting. Small quartz grains, 5 (micro)m in size, caused extensive foaming because their major portion dissolved at temperatures 800 C when batch gases no longer evolved. The exothermal reaction of nitrates with sucrose was ignited at a temperature as low as 160 C and caused a temporary jump in temperature of several hundred degrees. Secondary foam, the source of which is oxygen from redox reactions, occurred in all batches of a limited composition variation involving five oxides, B 2 O 3 , CaO, Li 2 O, MgO, and Na 2 O. The foam volume at the maximum volume-increase rate was a weak function of temperature and melt basicity. Neither the batch makeup nor the change in glass composition had a significant impact on the dissolution of silica grains. The impacts of primary foam generation on glass homogeneity and the rate of melting in large-scale continuous furnaces have yet to be established via mathematical modeling and melter experiments.

  7. Effect Of Glass-Batch Makeup On The Melting Process

    International Nuclear Information System (INIS)

    Kruger, A.A.; Hrma, P.

    2010-01-01

    The response of a glass batch to heating is determined by the batch makeup and in turn determines the rate of melting. Batches formulated for a high-alumina nuclear waste to be vitrified in an all-electric melter were heated at a constant temperature-increase rate to determine changes in melting behavior in response to the selection of batch chemicals and silica grain-size as well as the addition of heat-generating reactants. The type of batch materials and the size of silica grains determine how much, if any, primary foam occurs during melting. Small quartz grains, 5 (micro)m in size, caused extensive foaming because their major portion dissolved at temperatures 800 C when batch gases no longer evolved. The exothermal reaction of nitrates with sucrose was ignited at a temperature as low as 160 C and caused a temporary jump in temperature of several hundred degrees. Secondary foam, the source of which is oxygen from redox reactions, occurred in all batches of a limited composition variation involving five oxides, B 2 O 3 , CaO, Li 2 O, MgO, and Na 2 O. The foam volume at the maximum volume-increase rate was a weak function of temperature and melt basicity. Neither the batch makeup nor the change in glass composition had a significant impact on the dissolution of silica grains. The impacts of primary foam generation on glass homogeneity and the rate of melting in large-scale continuous furnaces have yet to be established via mathematical modeling and melter experiments.

  8. Application of the fuzzy theory to simulation of batch fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Filev, D P; Kishimoto, M; Sengupta, S; Yoshida, T; Taguchi, H

    1985-12-01

    A new approach for system identification with a linguistic model of batch fermentation processes is proposed. The fuzzy theory was applied in order to reduce the uncertainty of quantitative description of the processes by use of qualitative characteristics. An example of fuzzy modeling was illustrated in the simulation of batch ethanol production from molasses after interpretation of the new method, and extension of the fuzzy model was also discussed for several cases of different measurable variables.

  9. Expansion of protein domain repeats.

    Directory of Open Access Journals (Sweden)

    Asa K Björklund

    2006-08-01

    Full Text Available Many proteins, especially in eukaryotes, contain tandem repeats of several domains from the same family. These repeats have a variety of binding properties and are involved in protein-protein interactions as well as binding to other ligands such as DNA and RNA. The rapid expansion of protein domain repeats is assumed to have evolved through internal tandem duplications. However, the exact mechanisms behind these tandem duplications are not well-understood. Here, we have studied the evolution, function, protein structure, gene structure, and phylogenetic distribution of domain repeats. For this purpose we have assigned Pfam-A domain families to 24 proteomes with more sensitive domain assignments in the repeat regions. These assignments confirmed previous findings that eukaryotes, and in particular vertebrates, contain a much higher fraction of proteins with repeats compared with prokaryotes. The internal sequence similarity in each protein revealed that the domain repeats are often expanded through duplications of several domains at a time, while the duplication of one domain is less common. Many of the repeats appear to have been duplicated in the middle of the repeat region. This is in strong contrast to the evolution of other proteins that mainly works through additions of single domains at either terminus. Further, we found that some domain families show distinct duplication patterns, e.g., nebulin domains have mainly been expanded with a unit of seven domains at a time, while duplications of other domain families involve varying numbers of domains. Finally, no common mechanism for the expansion of all repeats could be detected. We found that the duplication patterns show no dependence on the size of the domains. Further, repeat expansion in some families can possibly be explained by shuffling of exons. However, exon shuffling could not have created all repeats.

  10. Polynomial Batch Codes for Efficient IT-PIR

    Directory of Open Access Journals (Sweden)

    Henry Ryan

    2016-10-01

    Full Text Available Private information retrieval (PIR is a way for clients to query a remote database without the database holder learning the clients’ query terms or the responses they generate. Compelling applications for PIR are abound in the cryptographic and privacy research literature, yet existing PIR techniques are notoriously inefficient. Consequently, no such PIRbased application to date has seen real-world at-scale deployment. This paper proposes new “batch coding” techniques to help address PIR’s efficiency problem. The new techniques exploit the connection between ramp secret sharing schemes and efficient information-theoretically secure PIR (IT-PIR protocols. This connection was previously observed by Henry, Huang, and Goldberg (NDSS 2013, who used ramp schemes to construct efficient “batch queries” with which clients can fetch several database records for the same cost as fetching a single record using a standard, non-batch query. The new techniques in this paper generalize and extend those of Henry et al. to construct “batch codes” with which clients can fetch several records for only a fraction the cost of fetching a single record using a standard non-batch query over an unencoded database. The batch codes are highly tuneable, providing a means to trade off (i lower server-side computation cost, (ii lower server-side storage cost, and/or (iii lower uni- or bi-directional communication cost, in exchange for a comparatively modest decrease in resilience to Byzantine database servers.

  11. Sludge Batch Variability Study With Frit 418

    International Nuclear Information System (INIS)

    Johnson, F.; Edwards, T.

    2010-01-01

    The Defense Waste Processing Facility (DWPF) initiated processing Sludge Batch 6 (SB6) in the summer of 2010. In support of processing, the Savannah River National Laboratory (SRNL) provided a recommendation to utilize Frit 418 to process SB6. This recommendation was based on assessments of the compositional projections for SB6 available at the time from the Liquid Waste Organization (LWO) and SRNL (using a model-based approach). To support qualification of SB6, SRNL executed a variability study to assess the applicability of the current durability models for SB6. The durability models were assessed over the expected Frit 418-SB6 composition range. Seventeen glasses were selected for the variability study based on the sludge projections used in the frit recommendation. Five of the glasses are based on the centroid of the compositional region, spanning a waste loading (WL) range of 32 to 40%. The remaining twelve glasses are extreme vertices (EVs) of the sludge region of interest for SB6 combined with Frit 418 and are all at 36% WL. These glasses were fabricated and characterized using chemical composition analysis, X-ray diffraction (XRD) and the Product Consistency Test (PCT). After initiating the SB6 variability study, the measured composition of the SB6 Tank 51 qualification glass produced at the SRNL Shielded Cells Facility indicated that thorium was present in the glass at an appreciable concentration (1.03 wt%), which made it a reportable element for SB6. This concentration of ThO 2 resulted in a second phase of experimental studies. Five glasses were formulated that were based on the centroid of the new sludge compositional region combined with Frit 418, spanning a WL range of 32 to 40%. These glasses were fabricated and characterized using chemical composition analysis and the PCT. Based on the measured PCT response, all of the glasses (with and without thorium) were acceptable with respect to the Environmental Assessment (EA) reference glass regardless of

  12. Improving lactate metabolism in an intensified CHO culture process: productivity and product quality considerations.

    Science.gov (United States)

    Xu, Sen; Hoshan, Linda; Chen, Hao

    2016-11-01

    In this study, we discussed the development and optimization of an intensified CHO culture process, highlighting medium and control strategies to improve lactate metabolism. A few strategies, including supplementing glucose with other sugars (fructose, maltose, and galactose), controlling glucose level at Productivity and product quality attributes differences between batch, fed-batch, and concentrated fed-batch cultures were discussed. The importance of process and cell metabolism understanding when adapting the existing process to a new operational mode was demonstrated in the study.

  13. Batch-to-Batch Quality Consistency Evaluation of Botanical Drug Products Using Multivariate Statistical Analysis of the Chromatographic Fingerprint

    OpenAIRE

    Xiong, Haoshu; Yu, Lawrence X.; Qu, Haibin

    2013-01-01

    Botanical drug products have batch-to-batch quality variability due to botanical raw materials and the current manufacturing process. The rational evaluation and control of product quality consistency are essential to ensure the efficacy and safety. Chromatographic fingerprinting is an important and widely used tool to characterize the chemical composition of botanical drug products. Multivariate statistical analysis has showed its efficacy and applicability in the quality evaluation of many ...

  14. Film repeats in radiology department

    International Nuclear Information System (INIS)

    Suwan, A. Z.; Al-Shakharah, A. I

    1997-01-01

    During a one year period, 4910 radiographs of 55780 films were repeated. The objective of our study was to analyse and to classify the causes in order to minimize the repeats, cut the expenses and to provide optimal radiographs for accurate diagnosis. Analysis of the different factors revealed that, 43.6% of film repeats in our service were due to faults in exposure factors, centering comprises 15.9% of the repeats, while too much collimation was responsible for 7.6% of these repeats. All of which can be decreased by awareness and programmed training of technicians. Film blurring caused by patient motion was also responsible for 4.9% for radiographs reexamination, which can be minimized by detailed explanation to the patient and providing the necessary privacy. Fogging of X-Ray films by improper storage or inadequate handling or processing faults were responsible for 14.5% in repeats in our study. Methods and criteria for proper storage and handling of films were discussed. Recommendation for using modern day-light and laser processor has been high lighted. Artefacts are noticeably high in our cases, due to spinal dresses and frequent usage of precious metals for c osmotic purposes in this part of the world. The repeated films comprise 8.8% of all films We conclude that, the main factor responsible for repeats of up to 81.6% of cases was the technologists, thus emphasizing the importance of adequate training of the technologists. (authors). 15 refs., 9 figs., 1 table

  15. Nifty Nines and Repeating Decimals

    Science.gov (United States)

    Brown, Scott A.

    2016-01-01

    The traditional technique for converting repeating decimals to common fractions can be found in nearly every algebra textbook that has been published, as well as in many precalculus texts. However, students generally encounter repeating decimal numerals earlier than high school when they study rational numbers in prealgebra classes. Therefore, how…

  16. Repeated Prescribed Burning in Aspen

    Science.gov (United States)

    Donald A. Perala

    1974-01-01

    Infrequent burning weather, low flammability of the aspen-hardwood association, and prolific sprouting and seeding of shrubs and hardwoods made repeated dormant season burning a poor tool to convert good site aspen to conifers. Repeat fall burns for wildlife habitat maintenance is workable if species composition changes are not important.

  17. Enhanced recombinant factor VII expression in Chinese hamster ovary cells by optimizing signal peptides and fed-batch medium.

    Science.gov (United States)

    Peng, Lin; Yu, Xiao; Li, Chengyuan; Cai, Yanfei; Chen, Yun; He, Yang; Yang, Jianfeng; Jin, Jian; Li, Huazhong

    2016-04-01

    Signal peptides play an important role in directing and efficiently transporting secretory proteins to their proper locations in the endoplasmic reticulum of mammalian cells. The aim of this study was to enhance the expression of recombinant coagulation factor VII (rFVII) in CHO cells by optimizing the signal peptides and type of fed-batch culture medium used. Five sub-clones (O2, I3, H3, G2 and M3) with different signal peptide were selected by western blot (WB) analysis and used for suspension culture. We compared rFVII expression levels of 5 sub-clones and found that the highest rFVII expression level was obtained with the IgK signal peptide instead of Ori, the native signal peptide of rFVII. The high protein expression of rFVII with signal peptide IgK was mirrored by a high transcription level during suspension culture. After analyzing culture and feed media, the combination of M4 and F4 media yielded the highest rFVII expression of 20 mg/L during a 10-day suspension culture. After analyzing cell density and cell cycle, CHO cells feeding by F4 had a similar percentage of cells in G0/G1 and a higher cell density compared to F2 and F3. This may be the reason for high rFVII expression in M4+F4. In summary, rFVII expression was successfully enhanced by optimizing the signal peptide and fed-batch medium used in CHO suspension culture. Our data may be used to improve the production of other therapeutic proteins in fed-batch culture.

  18. Tevatron serial data repeater system

    International Nuclear Information System (INIS)

    Ducar, R.J.

    1981-01-01

    A ten megabit per second serial data repeater system has been developed for the 6.28km Tevatron accelerator. The repeaters are positioned at each of the thirty service buildings and accommodate control and abort system communications as well as distribution of the Tevatron time and energy clocks. The repeaters are transparent to the particular protocol of the transmissions. Serial data are encoded locally as unipolar two volt signals employing the self-clocking Manchester Bi-Phase code. The repeaters modulate the local signals to low-power bursts of 50 MHz rf carrier for the 260m transmission between service buildings. The repeaters also demodulate the transmission and restructure the data for local utilization. The employment of frequency discrimination techniques yields high immunity to the characteristic noise spectrum

  19. All-photonic quantum repeaters

    Science.gov (United States)

    Azuma, Koji; Tamaki, Kiyoshi; Lo, Hoi-Kwong

    2015-01-01

    Quantum communication holds promise for unconditionally secure transmission of secret messages and faithful transfer of unknown quantum states. Photons appear to be the medium of choice for quantum communication. Owing to photon losses, robust quantum communication over long lossy channels requires quantum repeaters. It is widely believed that a necessary and highly demanding requirement for quantum repeaters is the existence of matter quantum memories. Here we show that such a requirement is, in fact, unnecessary by introducing the concept of all-photonic quantum repeaters based on flying qubits. In particular, we present a protocol based on photonic cluster-state machine guns and a loss-tolerant measurement equipped with local high-speed active feedforwards. We show that, with such all-photonic quantum repeaters, the communication efficiency scales polynomially with the channel distance. Our result paves a new route towards quantum repeaters with efficient single-photon sources rather than matter quantum memories. PMID:25873153

  20. Repeatability of visual acuity measurement.

    Science.gov (United States)

    Raasch, T W; Bailey, I L; Bullimore, M A

    1998-05-01

    This study investigates features of visual acuity chart design and acuity testing scoring methods which affect the validity and repeatability of visual acuity measurements. Visual acuity was measured using the Sloan and British Standard letter series, and Landolt rings. Identifiability of the different letters as a function of size was estimated, and expressed in the form of frequency-of-seeing curves. These functions were then used to simulate acuity measurements with a variety of chart designs and scoring criteria. Systematic relationships exist between chart design parameters and acuity score, and acuity score repeatability. In particular, an important feature of a chart, that largely determines the repeatability of visual acuity measurement, is the amount of size change attributed to each letter. The methods used to score visual acuity performance also affect repeatability. It is possible to evaluate acuity score validity and repeatability using the statistical principles discussed here.

  1. Control of a reactive batch distillation process using an iterative learning technique

    International Nuclear Information System (INIS)

    Ahn, Hyunsoo; Lee, Kwang Soon; Kim, Mansuk; Lee, Juhyun

    2014-01-01

    Quadratic criterion-based iterative learning control (QILC) was applied to a numerical reactive batch distillation process, in which methacrylic anhydride (MAN) is produced through the reaction of methacrylic acid with acetic anhydride. The role of distillation is to shift the equilibrium conversion toward the direction of the product by removing acetic acid (AcH), a by-product of the reaction. Two temperatures at both ends of the column were controlled by individual control loops. A nonlinear PID controller manipulating the reflux ratio was employed to regulate the top temperature at the boiling point of AcH. A constrained QILC was used for the tracking of the reactor temperature. A time-varying reference trajectory for the reactor temperature that satisfies the target conversion and purity of MAN was obtained through repeated simulations and confirmation experiments in the pilot plant. The QILC achieved satisfactory tracking in several batch runs with gentle control movements, while the PID control as a substitute of the QILC in a comparative study exhibited unacceptable performance

  2. Cloning, multicopy expression and fed-batch production of Rhodotorula araucariae epoxide hydrolase in yarrowia lipolytica

    CSIR Research Space (South Africa)

    Ramduth, D

    2008-05-01

    Full Text Available demonstrated a 4 fold enhanced EH activity over the transformant. The transformant was then evaluated in batch and fed batch fermentations, where the batch fermentations resulted in - 50% improved EH activity from flask evaluations. In fed batch fermentations...

  3. Application of culture dependent and cultural-independent techniques to investigate the dynamics of microorganisms during industrial cheese making of a Gouda type cheese

    OpenAIRE

    Perolari, Alessandra

    2012-01-01

    The aim of this work was to study the microbial dynamic in a Gouda type cheese applying a comparison between culture-dependent technique, plate count, and culture-independent technique as PCR-DGGE. The study was also focus on the analyse of the efficiency of the pasteurizer, and its cleaning steps. The study was conducted analysing 4 batches for each of the two days of production, Monday and Friday. Between batch 16 and 17 there was a quick cleaning, and between batch 32 and batch 1, of th...

  4. Long-term, repeated dose in vitro neurotoxicity of the glutamate receptor antagonist L-AP3, demonstrated in rat hippocampal slice cultures by using continuous propidium iodide incubation

    DEFF Research Database (Denmark)

    Kristensen, Bjarne W; Blaabjerg, Morten; Noraberg, Jens

    2007-01-01

    ), which is known to be toxic in vivo after subchronic, but not acute, administration. Degenerative effects were monitored by measuring the cellular uptake of propidium iodide (PI; continuously present in the medium) and lactate dehydrogenase (LDH) leakage, and by using a panel of histological stains....... Hippocampal slices, derived from 2-3 day old rats and grown for 3 weeks, were subsequently exposed for the next 3 weeks to 0, 10 or 100microM L-AP3, with PI (2microM) in the culture medium. Exposure to 100microM L-AP3 induced severe toxicity after 4-6 days, shown by massive PI uptake, LDH leakage, changes...... in MAP2 and GFAP immunostaining, and in Nissl and Timm staining. In contrast, 10microM L-AP3 did not induce detectable neuronal degeneration. Treatment with the NMDA receptor antagonist, MK-801, or the AMPA/KA receptor antagonist NBQX, together with 100microM L-AP3, reduced neurodegeneration down...

  5. Application of gain scheduling to the control of batch bioreactors

    Science.gov (United States)

    Cardello, Ralph; San, Ka-Yiu

    1987-01-01

    The implementation of control algorithms to batch bioreactors is often complicated by the inherent variations in process dynamics during the course of fermentation. Such a wide operating range may render the performance of fixed gain PID controllers unsatisfactory. In this work, a detailed study on the control of batch fermentation is performed. Furthermore, a simple batch controller design is proposed which incorporates the concept of gain-scheduling, a subclass of adaptive control, with oxygen uptake rate as an auxiliary variable. The control of oxygen tension in the biorector is used as a vehicle to convey the proposed idea, analysis and results. Simulation experiments indicate significant improvement in controller performance can be achieved by the proposed approach even in the presence of measurement noise.

  6. From Fed-batch to Continuous Enzymatic Biodiesel Production

    DEFF Research Database (Denmark)

    Price, Jason Anthony; Nordblad, Mathias; Woodley, John M.

    2015-01-01

    In this this paper, we use mechanistic modelling to guide the development of acontinuous enzymatic process that is performed as a fed-batch operation. In this workwe use the enzymatic biodiesel process as a case study. A mechanistic model developedin our previous work was used to determine...... measured components (triglycerides, diglycerides, monoglycerides, free fatty acid and fatty acid methyl esters(biodiesel)) much better than using fed-batch data alone given the smaller residuals. We also observe a reduction in the correlation between the parameters.The model was then used to predict that 5...... reactors are required (with a combined residence time of 30 hours) to reach a final biodiesel concentration within 2 % of the95.6 mass % achieved in a fed-batch operation, for 24 hours....

  7. Continuous flow technology vs. the batch-by-batch approach to produce pharmaceutical compounds.

    Science.gov (United States)

    Cole, Kevin P; Johnson, Martin D

    2018-01-01

    For the manufacture of small molecule drugs, many pharmaceutical innovator companies have recently invested in continuous processing, which can offer significant technical and economic advantages over traditional batch methodology. This Expert Review will describe the reasons for this interest as well as many considerations and challenges that exist today concerning continuous manufacturing. Areas covered: Continuous processing is defined and many reasons for its adoption are described. The current state of continuous drug substance manufacturing within the pharmaceutical industry is summarized. Current key challenges to implementation of continuous manufacturing are highlighted, and an outlook provided regarding the prospects for continuous within the industry. Expert commentary: Continuous processing at Lilly has been a journey that started with the need for increased safety and capability. Over twelve years the original small, dedicated group has grown to more than 100 Lilly employees in discovery, development, quality, manufacturing, and regulatory designing in continuous drug substance processing. Recently we have focused on linked continuous unit operations for the purpose of all-at-once pharmaceutical manufacturing, but the technical and business drivers that existed in the very beginning for stand-alone continuous unit operations in hybrid processes have persisted, which merits investment in both approaches.

  8. A High-Fidelity Batch Simulation Environment for Integrated Batch and Piloted Air Combat Simulation Analysis

    Science.gov (United States)

    Goodrich, Kenneth H.; McManus, John W.; Chappell, Alan R.

    1992-01-01

    A batch air combat simulation environment known as the Tactical Maneuvering Simulator (TMS) is presented. The TMS serves as a tool for developing and evaluating tactical maneuvering logics. The environment can also be used to evaluate the tactical implications of perturbations to aircraft performance or supporting systems. The TMS is capable of simulating air combat between any number of engagement participants, with practical limits imposed by computer memory and processing power. Aircraft are modeled using equations of motion, control laws, aerodynamics and propulsive characteristics equivalent to those used in high-fidelity piloted simulation. Databases representative of a modern high-performance aircraft with and without thrust-vectoring capability are included. To simplify the task of developing and implementing maneuvering logics in the TMS, an outer-loop control system known as the Tactical Autopilot (TA) is implemented in the aircraft simulation model. The TA converts guidance commands issued by computerized maneuvering logics in the form of desired angle-of-attack and wind axis-bank angle into inputs to the inner-loop control augmentation system of the aircraft. This report describes the capabilities and operation of the TMS.

  9. Analysis of repeated measures data

    CERN Document Server

    Islam, M Ataharul

    2017-01-01

    This book presents a broad range of statistical techniques to address emerging needs in the field of repeated measures. It also provides a comprehensive overview of extensions of generalized linear models for the bivariate exponential family of distributions, which represent a new development in analysing repeated measures data. The demand for statistical models for correlated outcomes has grown rapidly recently, mainly due to presence of two types of underlying associations: associations between outcomes, and associations between explanatory variables and outcomes. The book systematically addresses key problems arising in the modelling of repeated measures data, bearing in mind those factors that play a major role in estimating the underlying relationships between covariates and outcome variables for correlated outcome data. In addition, it presents new approaches to addressing current challenges in the field of repeated measures and models based on conditional and joint probabilities. Markov models of first...

  10. Repeated DNA sequences in fungi

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, S K

    1974-11-01

    Several fungal species, representatives of all broad groups like basidiomycetes, ascomycetes and phycomycetes, were examined for the nature of repeated DNA sequences by DNA:DNA reassociation studies using hydroxyapatite chromatography. All of the fungal species tested contained 10 to 20 percent repeated DNA sequences. There are approximately 100 to 110 copies of repeated DNA sequences of approximately 4 x 10/sup 7/ daltons piece size of each. Repeated DNA sequence homoduplexes showed on average 5/sup 0/C difference of T/sub e/50 (temperature at which 50 percent duplexes dissociate) values from the corresponding homoduplexes of unfractionated whole DNA. It is suggested that a part of repetitive sequences in fungi constitutes mitochondrial DNA and a part of it constitutes nuclear DNA. (auth)

  11. Fed-batch bioreactor performance and cell line stability evaluation of the artificial chromosome expression technology expressing an IgG1 in Chinese hamster ovary cells.

    Science.gov (United States)

    Combs, Rodney G; Yu, Erwin; Roe, Susanna; Piatchek, Michele Bailey; Jones, Heather L; Mott, John; Kennard, Malcolm L; Goosney, Danika L; Monteith, Diane

    2011-01-01

    The artificial chromosome expression (ACE) technology system uses an engineered artificial chromosome containing multiple site-specific recombination acceptor sites for the rapid and efficient construction of stable cell lines. The construction of Chinese hamster ovary(CHO) cell lines expressing an IgG1 monoclonal antibody (MAb) using the ACE system has been previously described (Kennard et al., Biotechnol Bioeng. 2009;104:540-553). To further demonstrate the manufacturing feasibility of the ACE system, four CHO cell lines expressing the human IgG1 MAb 4A1 were evaluated in batch and fed-batch shake flasks and in a 2-L fed-batch bioreactor. The batch shake flasks achieved titers between 0.7 and 1.1 g/L, whereas the fed-batch shake flask process improved titers to 2.5–3.0 g/L. The lead 4A1 ACE cell line achieved titers of 4.0 g/L with an average specific productivity of 40 pg/(cell day) when cultured in a non optimized 2-L fed-batch bioreactor using a completely chemically defined process. Generational stability characterization of the lead 4A1-expressing cell line demonstrated that the cell line was stable for up to 75 days in culture. Product quality attributes of the 4A1 MAb produced by the ACE system during the stability evaluation period were unchanged and also comparable to existing expression technologies such as the CHO-dhfr system. The results of this evaluation demonstrate that a clonal, stable MAb-expressing CHO cell line can be produced using ACE technology that performs competitively using a chemically defined fed-batch bioreactor process with comparable product quality attributes to cell lines generated by existing technologies.

  12. Stochastic growth logistic model with aftereffect for batch fermentation process

    Science.gov (United States)

    Rosli, Norhayati; Ayoubi, Tawfiqullah; Bahar, Arifah; Rahman, Haliza Abdul; Salleh, Madihah Md

    2014-06-01

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits.

  13. Stochastic growth logistic model with aftereffect for batch fermentation process

    International Nuclear Information System (INIS)

    Rosli, Norhayati; Ayoubi, Tawfiqullah; Bahar, Arifah; Rahman, Haliza Abdul; Salleh, Madihah Md

    2014-01-01

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits

  14. Stochastic growth logistic model with aftereffect for batch fermentation process

    Energy Technology Data Exchange (ETDEWEB)

    Rosli, Norhayati; Ayoubi, Tawfiqullah [Faculty of Industrial Sciences and Technology, Universiti Malaysia Pahang, Lebuhraya Tun Razak, 26300 Gambang, Pahang (Malaysia); Bahar, Arifah; Rahman, Haliza Abdul [Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia); Salleh, Madihah Md [Department of Biotechnology Industry, Faculty of Biosciences and Bioengineering, Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia)

    2014-06-19

    In this paper, the stochastic growth logistic model with aftereffect for the cell growth of C. acetobutylicum P262 and Luedeking-Piret equations for solvent production in batch fermentation system is introduced. The parameters values of the mathematical models are estimated via Levenberg-Marquardt optimization method of non-linear least squares. We apply Milstein scheme for solving the stochastic models numerically. The effciency of mathematical models is measured by comparing the simulated result and the experimental data of the microbial growth and solvent production in batch system. Low values of Root Mean-Square Error (RMSE) of stochastic models with aftereffect indicate good fits.

  15. Optimum heat storage design for heat integrated multipurpose batch plants

    CSIR Research Space (South Africa)

    Stamp, J

    2011-01-01

    Full Text Available procedure is presented tha journal homepage: www All rights reserved. ajozi T, Optimum heat storage grated multipurpose batch plants , South Africa y usage in multipurpose batch plants has been in published literature most present methods, time... � 2pL?u?kins ? 1 h3A3?u?cu?U (36) The internal area for heat loss by convection from the heat transfer medium is given by Constraint (37) and the area for convective heat transfer losses to the environment is given in Constraint (38). A1?u? ? 2...

  16. Fostering repeat donations in Ghana.

    Science.gov (United States)

    Owusu-Ofori, S; Asenso-Mensah, K; Boateng, P; Sarkodie, F; Allain, J-P

    2010-01-01

    Most African countries are challenged in recruiting and retaining voluntary blood donors by cost and other complexities and in establishing and implementing national blood policies. The availability of replacement donors who are a cheaper source of blood has not enhanced repeat voluntary donor initiatives. An overview of activities for recruiting and retaining voluntary blood donors was carried out. Donor records from mobile sessions were reviewed from 2002 to 2008. A total of 71,701 blood donations; 45,515 (63.5%) being voluntary donations with 11,680 (25%) repeat donations were collected during the study period. Donations from schools and colleges contributed a steady 60% of total voluntary whilst radio station blood drives increased contribution from 10 to 27%. Though Muslim population is less than 20%, blood collection was above the 30-donation cost-effectiveness threshold with a repeat donation trend reaching 60%. In contrast Christian worshippers provided donations. Repeat donation trends amongst school donors and radio blood drives were 20% and 70% respectively. Repeat donations rates have been variable amongst different blood donor groups in Kumasi, Ghana. The impact of community leaders in propagating altruism cannot be overemphasized. Programs aiming at motivating replacement donors to be repeat donors should be developed and assessed. Copyright 2009 The International Association for Biologicals. All rights reserved.

  17. Effect of starter cultures on microbial and physicochemical ...

    African Journals Online (AJOL)

    sunny

    2014-10-22

    Oct 22, 2014 ... 1Research Unity, Food and Science Technologies–UR 04 AGR02, High Food Industries School of Tunisia, 58 Avenue .... The mixture of each batch was stuffed into artificial ..... Effects of starter cultures and additives on.

  18. User-friendly optimization approach of fed-batch fermentation conditions for the production of iturin A using artificial neural networks and support vector machine

    Directory of Open Access Journals (Sweden)

    Fudi Chen

    2015-07-01

    Conclusion: According to the modeling results, the GRNN is considered as the most suitable ANN model for the design of the fed-batch fermentation conditions for the production of iturin A because of its high robustness and precision, and the SVM is also considered as a very suitable alternative model. Under the tolerance of 30%, the prediction accuracies of the GRNN and SVM are both 100% respectively in repeated experiments.

  19. Design of two-column batch-to-batch recirculation to enhance performance in ion-exchange chromatography.

    Science.gov (United States)

    Persson, Oliver; Andersson, Niklas; Nilsson, Bernt

    2018-01-05

    Preparative liquid chromatography is a separation technique widely used in the manufacturing of fine chemicals and pharmaceuticals. A major drawback of traditional single-column batch chromatography step is the trade-off between product purity and process performance. Recirculation of impure product can be utilized to make the trade-off more favorable. The aim of the present study was to investigate the usage of a two-column batch-to-batch recirculation process step to increase the performance compared to single-column batch chromatography at a high purity requirement. The separation of a ternary protein mixture on ion-exchange chromatography columns was used to evaluate the proposed process. The investigation used modelling and simulation of the process step, experimental validation and optimization of the simulated process. In the presented case the yield increases from 45.4% to 93.6% and the productivity increases 3.4 times compared to the performance of a batch run for a nominal case. A rapid concentration build-up product can be seen during the first cycles, before the process reaches a cyclic steady-state with reoccurring concentration profiles. The optimization of the simulation model predicts that the recirculated salt can be used as a flying start of the elution, which would enhance the process performance. The proposed process is more complex than a batch process, but may improve the separation performance, especially while operating at cyclic steady-state. The recirculation of impure fractions reduces the product losses and ensures separation of product to a high degree of purity. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Biodegradable poly-ε-caprolactone microcarriers for efficient production of human mesenchymal stromal cells and secreted cytokines in batch and fed-batch bioreactors.

    Science.gov (United States)

    Lam, Alan Tin-Lun; Li, Jian; Toh, Jessica Pei-Wen; Sim, Eileen Jia-Hui; Chen, Allen Kuan-Liang; Chan, Jerry Kok-Yen; Choolani, Mahesh; Reuveny, Shaul; Birch, William R; Oh, Steve Kah-Weng

    2017-03-01

    Large numbers of human mesenchymal stromal cells (MSCs) used for a variety of applications in tissue engineering and cell therapy can be generated by scalable expansion in a bioreactor using microcarriers (MCs) systems. However, the enzymatic digestion process needed to detach cells from the growth surface can affect cell viability and potentially the potency and differentiation efficiency. Thus, the main aim of our study was to develop biocompatible and biodegradable MCs that can support high MSC yields while maintaining their differentiation capability and potency. After cell expansion, the cells that covered MCs can be directly implanted in vivo without the need for cell harvesting or use of scaffold. Poly-ε-caprolactone (PCL) is known as a biocompatible and biodegradable material. However, it cannot be used for generation of MCs because its high density (1.14 g/cm 3 ) would exclude its applicability for suspension MCs in stirred reactors. In this article, we describe expansion and potency of MSCs propagated on low-density (1.06 g/cm 3 ) porous PCL MCs coated with extracellular matrices (LPCLs) in suspended stirred reactors. Using these LPCLs, cell yields of about 4 × 10 4 cells/cm 2 and 7- to 10-fold increases were obtained using four different MSC lines (bone marrow, cord blood, fetal and Wharton's jelly). These yields were comparable with those obtained using non-degradable MCs (Cytodex 3) and higher than two-dimensional monolayer (MNL) cultures. A fed-batch process, which demonstrated faster cell expansion (4.5 × 10 4 cells/cm 2 in 5 days as compared with 7 days in batch culture) and about 70% reduction in growth media usage, was developed and scaled up from 100-mL spinner flask to 1-L controlled bioreactor. Surface marker expression, trilineage differentiation and clonogenic potential of the MSCs expanded on LPCL were not affected. Cytokine secretion kinetics, which occurred mostly during late logarithmic phase, was usually comparable with

  1. Evaluation of human platelet lysate versus fetal bovine serum for culture of mesenchymal stromal cells.

    Science.gov (United States)

    Hemeda, Hatim; Giebel, Bernd; Wagner, Wolfgang

    2014-02-01

    Culture media for therapeutic cell preparations-such as mesenchymal stromal cells (MSCs)-usually comprise serum additives. Traditionally, fetal bovine serum is supplemented in basic research and in most clinical trials. Within the past years, many laboratories adapted their culture conditions to human platelet lysate (hPL), which further stimulates proliferation and expansion of MSCs. Particularly with regard to clinical application, human alternatives for fetal bovine serum are clearly to be preferred. hPL is generated from human platelet units by disruption of the platelet membrane, which is commonly performed by repeated freeze and thaw cycles. Such culture supplements are notoriously ill-defined, and many parameters contribute to batch-to-batch variation in hPL such as different amounts of plasma, a broad range of growth factors and donor-specific effects. The plasma components of hPL necessitate addition of anticoagulants such as heparins to prevent gelatinization of hPL medium, and their concentration must be standardized. Labels for description of hPL-such as "xenogen-free," "animal-free" and "serum free"-are not used consistently in the literature and may be misleading if not critically assessed. Further analysis of the precise composition of relevant growth factors, attachment factors, microRNAs and exosomes will pave the way for optimized and defined culture conditions. The use of hPL has several advantages and disadvantages: they must be taken into account because the choice of cell culture additive has major impact on cell preparations. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  2. Adaptation to high throughput batch chromatography enhances multivariate screening.

    Science.gov (United States)

    Barker, Gregory A; Calzada, Joseph; Herzer, Sibylle; Rieble, Siegfried

    2015-09-01

    High throughput process development offers unique approaches to explore complex process design spaces with relatively low material consumption. Batch chromatography is one technique that can be used to screen chromatographic conditions in a 96-well plate. Typical batch chromatography workflows examine variations in buffer conditions or comparison of multiple resins in a given process, as opposed to the assessment of protein loading conditions in combination with other factors. A modification to the batch chromatography paradigm is described here where experimental planning, programming, and a staggered loading approach increase the multivariate space that can be explored with a liquid handling system. The iterative batch chromatography (IBC) approach is described, which treats every well in a 96-well plate as an individual experiment, wherein protein loading conditions can be varied alongside other factors such as wash and elution buffer conditions. As all of these factors are explored in the same experiment, the interactions between them are characterized and the number of follow-up confirmatory experiments is reduced. This in turn improves statistical power and throughput. Two examples of the IBC method are shown and the impact of the load conditions are assessed in combination with the other factors explored. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Control of polymer network topology in semi-batch systems

    Science.gov (United States)

    Wang, Rui; Olsen, Bradley; Johnson, Jeremiah

    Polymer networks invariably possess topological defects: loops of different orders. Since small loops (primary loops and secondary loops) both lower the modulus of network and lead to stress concentration that causes material failure at low deformation, it is desirable to greatly reduce the loop fraction. We have shown that achieving loop fraction close to zero is extremely difficult in the batch process due to the slow decay of loop fraction with the polymer concentration and chain length. Here, we develop a modified kinetic graph theory that can model network formation reactions in semi-batch systems. We demonstrate that the loop fraction is not sensitive to the feeding policy if the reaction volume maintains constant during the network formation. However, if we initially put concentrated solution of small junction molecules in the reactor and continuously adding polymer solutions, the fractions of both primary loop and higher-order loops will be significantly reduced. There is a limiting value (nonzero) of loop fraction that can be achieved in the semi-batch system in condition of extremely slow feeding rate. This minimum loop fraction only depends on a single dimensionless variable, the product of concentration and with single chain pervaded volume, and defines an operating zone in which the loop fraction of polymer networks can be controlled through adjusting the feeding rate of the semi-batch process.

  4. State and parameter estimation in biotechnical batch reactors

    NARCIS (Netherlands)

    Keesman, K.J.

    2000-01-01

    In this paper the problem of state and parameter estimation in biotechnical batch reactors is considered. Models describing the biotechnical process behaviour are usually nonlinear with time-varying parameters. Hence, the resulting large dimensions of the augmented state vector, roughly > 7, in

  5. Batch distillation column modeling for quality control program

    NARCIS (Netherlands)

    Betlem, Bernardus H.L.

    2000-01-01

    For batch distillation, the dynamic composition behaviour can be described by the dominant time constant and the bottom exhaustion. Its magnitude is determined by the change of the composition distribution and is maximal when the inflection point of the molar fraction profile is located in the

  6. Sequencing for Batch Production in a Group Flowline Machine Shop ...

    African Journals Online (AJOL)

    The purpose of the paper is to develop a useful technique for sequencing batches of components through machine shops arranged under the group flowline production system. The approach is to apply a modified version of Petrov's group flowline technique for machining components which follow a unidirectional route.

  7. Quality control for 12 batch of DTPA-Sn

    International Nuclear Information System (INIS)

    Isaac, M.; Gamboa, R.; Leyva, R.; Hernandez, I.; Turino, D.

    1994-01-01

    The quality control is carry out at 12 batch of DTPA-Sn for labeling with 99 m Tc. The instrumental methods of analysis and control charts were discussed in order to find a warranty time for the product. (author). 2 refs, 3 figs, 1 tab

  8. Flash chemistry: flow chemistry that cannot be done in batch.

    Science.gov (United States)

    Yoshida, Jun-ichi; Takahashi, Yusuke; Nagaki, Aiichiro

    2013-11-04

    Flash chemistry based on high-resolution reaction time control using flow microreactors enables chemical reactions that cannot be done in batch and serves as a powerful tool for laboratory synthesis of organic compounds and for production in chemical and pharmaceutical industries.

  9. Adsorption of Arsenite onto Kemiron in a batch system

    African Journals Online (AJOL)

    doti

    This study investigated the effect of pH and coexisting ions on As(III) adsorption using batch experiment and discovered that pH strongly influenced As(III) adsorption. However, differences ... contamination by such heavy metals as arsenic (As). Arsenite ..... and then transition through point of zero charge (PZC) and then into ...

  10. Development of Production Control in Small Batch Production

    Directory of Open Access Journals (Sweden)

    Németh Péter

    2016-01-01

    Full Text Available Our aim with this paper is to develop a new performance measurement and control system for small batch production in the automotive industry. For this reason, we present our previous research results for warehouse performance measurement and adopt its methodology to production control. The proposed method is based on artificial intelligence (neural networks.

  11. Shell of Planet Earth – Global Batch Bioreactor.

    Czech Academy of Sciences Publication Activity Database

    Hanika, Jiří; Šolcová, Olga; Kaštánek, P.

    2017-01-01

    Roč. 40, č. 11 (2017), s. 1959-1965 ISSN 0930-7516 R&D Projects: GA TA ČR TE01020080 Institutional support: RVO:67985858 Keywords : critical raw materials * global batch bioreactor * planet earth Subject RIV: CI - Industrial Chemistry, Chemical Engineering OBOR OECD: Chemical process engineering Impact factor: 2.051, year: 2016

  12. A fixed-size batch service queue with vacations

    Directory of Open Access Journals (Sweden)

    Ho Woo Lee

    1996-01-01

    Full Text Available The paper deals with batch service queues with vacations in which customers arrive according to a Poisson process. Decomposition method is used to derive the queue length distributions both for single and multiple vacation cases. The authors look at other decomposition techniques and discuss some related open problems.

  13. Optimization of heat-liberating batches for ash residue stabilization

    International Nuclear Information System (INIS)

    Karlina, O.K.; Varlackova, G.A.; Ojovan, M.I.; Tivansky, V.M.; Dmitriev, S.A.

    1999-01-01

    The ash residue obtained after incineration of solid radioactive waste is a dusting poly-dispersed powder like material that contains radioactive nuclides ( 137 Cs, 90 Sr, 239 Pu, hor ( ellipsis)). Specific radioactivity of the ash can be about 10 5 --10 7 Bq/kg. In order to dispose of the ash, residue shall be stabilized by producing a monolith material. The ash residue can be either vitrified or stabilized into a ceramic matrix. For this purpose the ash residue is mixed with fluxing agents followed by melting of obtained composition in the different type melters. As a rule this requires both significant energy consumption and complex melting equipment. A stabilization technology of ash residue was proposed recently by using heat liberating batches-compositions with redox properties. The ash residue is melted due to exothermic chemical reactions in the mixture with heat-liberating batch that occur with considerable release of heat. Stabilization method has three stages: (1) preparation of a mixture of heating batch and ash residue with or without glass forming batch (frit); (2) ignition and combustion of mixed composition; (3) cooling (quenching) of obtained vitreous material. Combustion of mixed composition occurs in the form of propagation of reacting wave. The heat released during exothermic chemical reactions provides melting of ash residue components and production of glass-like phase. The final product consists of a glass like matrix with embedded crystalline inclusions of infusible ash residue components

  14. Comparative Batch and Column Evaluation of Thermal and Wet ...

    African Journals Online (AJOL)

    The efficiency of regenerated spent commercial activated carbon for synthetic dye removal was studied using thermal and wet oxidative regeneration methods. Two types of experiments were carried out, batch adsorption experiments and continous flow (fixed bed) column experiment to study the mechanism of dye removal ...

  15. DEVELOPMENT OF AN AUTOMATED BATCH-PROCESS SOLAR ...

    African Journals Online (AJOL)

    One of the shortcomings of solar disinfection of water (SODIS) is the absence of a feedback mechanism indicating treatment completion. This work presents the development of an automated batch-process water disinfection system aimed at solving this challenge. Locally sourced materials in addition to an Arduinomicro ...

  16. Batch immunoextraction method for efficient purification of aromatic cytokinins

    Czech Academy of Sciences Publication Activity Database

    Hauserová, Eva; Swaczynová, Jana; Doležal, Karel; Lenobel, René; Popa, Igor; Hajdúch, M.; Vydra, D.; Fuksová, Květoslava; Strnad, Miroslav

    2005-01-01

    Roč. 1100, č. 1 (2005), s. 116-125 ISSN 0021-9673 R&D Projects: GA AV ČR IBS4055304 Institutional research plan: CEZ:AV0Z50380511; MSM6198959216 Keywords : antibody * 6-benzylaminopurine * batch immunoextraction Subject RIV: ED - Physiology Impact factor: 3.096, year: 2005

  17. Tier 3 batch system data locality via managed caches

    Science.gov (United States)

    Fischer, Max; Giffels, Manuel; Jung, Christopher; Kühn, Eileen; Quast, Günter

    2015-05-01

    Modern data processing increasingly relies on data locality for performance and scalability, whereas the common HEP approaches aim for uniform resource pools with minimal locality, recently even across site boundaries. To combine advantages of both, the High- Performance Data Analysis (HPDA) Tier 3 concept opportunistically establishes data locality via coordinated caches. In accordance with HEP Tier 3 activities, the design incorporates two major assumptions: First, only a fraction of data is accessed regularly and thus the deciding factor for overall throughput. Second, data access may fallback to non-local, making permanent local data availability an inefficient resource usage strategy. Based on this, the HPDA design generically extends available storage hierarchies into the batch system. Using the batch system itself for scheduling file locality, an array of independent caches on the worker nodes is dynamically populated with high-profile data. Cache state information is exposed to the batch system both for managing caches and scheduling jobs. As a result, users directly work with a regular, adequately sized storage system. However, their automated batch processes are presented with local replications of data whenever possible.

  18. modelling and simulation of the batch hydrolysis of acetic ing

    African Journals Online (AJOL)

    eobe

    The kinetic modelling of the batch synthesis of acetic acid from acetic. The kinetic modelling of ... integral method of analysis to determine the kinetic parameters .... Equation (5) is applied to all the components ... In common chemical engineering terminology, the degree of ..... of Physical Organic Chemistry, Vol. 25, Number ...

  19. Comparison of neptunium sorption results using batch and column techniques

    International Nuclear Information System (INIS)

    Triay, I.R.; Furlano, A.C.; Weaver, S.C.; Chipera, S.J.; Bish, D.L.

    1996-08-01

    We used crushed-rock columns to study the sorption retardation of neptunium by zeolitic, devitrified, and vitric tuffs typical of those at the site of the potential high-level nuclear waste repository at Yucca Mountain, Nevada. We used two sodium bicarbonate waters (groundwater from Well J-13 at the site and water prepared to simulate groundwater from Well UE-25p No. 1) under oxidizing conditions. It was found that values of the sorption distribution coefficient, Kd, obtained from these column experiments under flowing conditions, regardless of the water or the water velocity used, agreed well with those obtained earlier from batch sorption experiments under static conditions. The batch sorption distribution coefficient can be used to predict the arrival time for neptunium eluted through the columns. On the other hand, the elution curves showed dispersivity, which implies that neptunium sorption in these tuffs may be nonlinear, irreversible, or noninstantaneous. As a result, use of a batch sorption distribution coefficient to calculate neptunium transport through Yucca Mountain tuffs would yield conservative values for neptunium release from the site. We also noted that neptunium (present as the anionic neptunyl carbonate complex) never eluted prior to tritiated water, which implies that charge exclusion does not appear to exclude neptunium from the tuff pores. The column experiments corroborated the trends observed in batch sorption experiments: neptunium sorption onto devitrified and vitric tuffs is minimal and sorption onto zeolitic tuffs decreases as the amount of sodium and bicarbonate/carbonate in the water increases

  20. Oxidative stress adaptation with acute, chronic, and repeated stress.

    Science.gov (United States)

    Pickering, Andrew M; Vojtovich, Lesya; Tower, John; A Davies, Kelvin J

    2013-02-01

    Oxidative stress adaptation, or hormesis, is an important mechanism by which cells and organisms respond to, and cope with, environmental and physiological shifts in the level of oxidative stress. Most studies of oxidative stress adaption have been limited to adaptation induced by acute stress. In contrast, many if not most environmental and physiological stresses are either repeated or chronic. In this study we find that both cultured mammalian cells and the fruit fly Drosophila melanogaster are capable of adapting to chronic or repeated stress by upregulating protective systems, such as their proteasomal proteolytic capacity to remove oxidized proteins. Repeated stress adaptation resulted in significant extension of adaptive responses. Repeated stresses must occur at sufficiently long intervals, however (12-h or more for MEF cells and 7 days or more for flies), for adaptation to be successful, and the levels of both repeated and chronic stress must be lower than is optimal for adaptation to acute stress. Regrettably, regimens of adaptation to both repeated and chronic stress that were successful for short-term survival in Drosophila nevertheless also caused significant reductions in life span for the flies. Thus, although both repeated and chronic stress can be tolerated, they may result in a shorter life. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Hysteresis of magnetostructural transitions: Repeatable and non-repeatable processes

    Science.gov (United States)

    Provenzano, Virgil; Della Torre, Edward; Bennett, Lawrence H.; ElBidweihy, Hatem

    2014-02-01

    The Gd5Ge2Si2 alloy and the off-stoichiometric Ni50Mn35In15 Heusler alloy belong to a special class of metallic materials that exhibit first-order magnetostructural transitions near room temperature. The magnetic properties of this class of materials have been extensively studied due to their interesting magnetic behavior and their potential for a number of technological applications such as refrigerants for near-room-temperature magnetic refrigeration. The thermally driven first-order transitions in these materials can be field-induced in the reverse order by applying a strong enough field. The field-induced transitions are typically accompanied by the presence of large magnetic hysteresis, the characteristics of which are a complicated function of temperature, field, and magneto-thermal history. In this study we show that the virgin curve, the major loop, and sequentially measured MH loops are the results of both repeatable and non-repeatable processes, in which the starting magnetostructural state, prior to the cycling of field, plays a major role. Using the Gd5Ge2Si2 and Ni50Mn35In15 alloys, as model materials, we show that a starting single phase state results in fully repeatable processes and large magnetic hysteresis, whereas a mixed phase starting state results in non-repeatable processes and smaller hysteresis.

  2. Hysteresis of magnetostructural transitions: Repeatable and non-repeatable processes

    International Nuclear Information System (INIS)

    Provenzano, Virgil; Della Torre, Edward; Bennett, Lawrence H.; ElBidweihy, Hatem

    2014-01-01

    The Gd 5 Ge 2 Si 2 alloy and the off-stoichiometric Ni 50 Mn 35 In 15 Heusler alloy belong to a special class of metallic materials that exhibit first-order magnetostructural transitions near room temperature. The magnetic properties of this class of materials have been extensively studied due to their interesting magnetic behavior and their potential for a number of technological applications such as refrigerants for near-room-temperature magnetic refrigeration. The thermally driven first-order transitions in these materials can be field-induced in the reverse order by applying a strong enough field. The field-induced transitions are typically accompanied by the presence of large magnetic hysteresis, the characteristics of which are a complicated function of temperature, field, and magneto-thermal history. In this study we show that the virgin curve, the major loop, and sequentially measured MH loops are the results of both repeatable and non-repeatable processes, in which the starting magnetostructural state, prior to the cycling of field, plays a major role. Using the Gd 5 Ge 2 Si 2 and Ni 50 Mn 35 In 15 alloys, as model materials, we show that a starting single phase state results in fully repeatable processes and large magnetic hysteresis, whereas a mixed phase starting state results in non-repeatable processes and smaller hysteresis

  3. Exponential fed-batch strategy for enhancing biosurfactant production by Bacillus subtilis.

    Science.gov (United States)

    Amin, G A

    2014-01-01

    Surfactin produced by Bacillus subtilis BDCC-TUSA-3 from Maldex-15 was used as a growth-associated product in a conventional batch process. Maldex-15 is a cheap industrial by-product recovered during manufacturing of high fructose syrup from corn starch. Surfactin production was greatly improved in exponential fed-batch fermentation. Maldex-15 and other nutrients were exponentially fed into the culture based on the specific growth rate of the bacterium. In order to maximize surfactin yield and productivity, conversion of different quantities of Maldex-15 into surfactin was investigated in five different fermentation runs. In all runs, most of the Maldex-15 was consumed and converted into surfactin and cell biomass with appreciable efficiencies. The best results were obtained with the fermentation run supplied with 204 g Maldex-15. Up to 36.1 g l(-1) of surfactin and cell biomass of 31.8 g l(-1) were achieved in 12 h. Also, a marked substrate yield of 0.272 g g(-1) and volumetric reactor productivity of 2.58 g 1(-1) h(-1) were obtained, confirming the establishment of a cost-effective commercial surfactin production.

  4. Using a medium of free amino acids to produce penicillin g acylase in fed-batch cultivations of Bacillus megaterium ATCC 14945

    Directory of Open Access Journals (Sweden)

    R. G. Silva

    2006-03-01

    Full Text Available The production of penicillin G acylase (PGA, an important industrial enzyme from a wild strain of Bacillus megaterium using a pool of free amino acids as substrate was studied in a bench-scale bioreactor. Experiments carried out in shakers showed that the substitution of casein for free amino acids in the presence of cheese whey was the culture medium that provided the highest productivity. Several cultivations were carried out in a bioreactor operated in either batch or fed-batch mode. Batch runs showed that enzyme production is associated with microorganism growth. The following set of amino acids was preferentially consumed: Ala, Arg, Asp, Gly, Lys, Ser, Thr and Trp. On the other hand, the rates of consumption of His, Ile, Leu, Met, Phe, Pro, Tyr and Val were lower.

  5. Coordination in continuously repeated games

    NARCIS (Netherlands)

    Weeren, A.J.T.M.; Schumacher, J.M.; Engwerda, J.C.

    1995-01-01

    In this paper we propose a model to describe the effectiveness of coordination in a continuously repeated two-player game. We study how the choice of a decision rule by a coordinator affects the strategic behavior of the players, resulting in more or less cooperation. Our model requires the analysis

  6. Repeated checking causes memory distrust

    NARCIS (Netherlands)

    van den Hout, M.; Kindt, M.

    2003-01-01

    This paper attempts to explain why in obsessive-compulsive disorder (OCD) checkers distrust in memory persists despite extensive checking. It is argued that: (1) repeated checking increases familiarity with the issues checked; (2) increased familiarity promotes conceptual processing which inhibits

  7. [Study on causes and treatment of repeated vulvovaginitis in girlhood].

    Science.gov (United States)

    Zhang, Di-kai; Li, Xiu-yun; Yang, Dong-zi; Kuang, Jian-quan

    2006-07-01

    To explore the causes and treatment of repeated vulvovaginitis in girlhood in order to improve its prevention and treatment. Fifty-one girls with repeated vulvovaginitis (age vulvovaginitis and 14 ones (27%) suffering from posterior recto-vaginal fistula with in 51 patients. Five girls (10%) were smitten with vulval ulcer and 3 ones (6%) had been were found with vaginal foreign bodies. One girl (2%) was smitten with adhesion of labia minora. The vaginal discharges taken from 21 girls were cultured. Seventeen cases found bacteria. The positive rate of bacteria culture in the 21 cases reached 81%, in which, E.coli accounted for 5 cases (24%), staphylococcus and streptococcus accounted for 3 cases (14%) respectively. Patients suffering from non-specific vulvovaginitis and vulval ulcer accepted external lotion, antibiotic ointment or combining with antibiotics. Patients suffering from posterior recto-vaginal fistula accepted fistulectomy. Three girls who found vaginal foreign bodies took out of foreign bodies by hysteroscope. Fifty-one girls all were cured after appropriate therapy. Vulvovaginitis is the most common gynecologic diagnosis in girlhood. The principal cause of repeated invasion is non-specific vulvovaginitis and the secondly one is posterior recto-vaginal fistula. It need overhaul during the diagnosis. It is very availability to use hysteroscopy and do bacteria culture + antibiotic sensitivity test for repeated pediatric vulvovaginitis.

  8. Production and partial characterization of alkaline feruloyl esterases by Fusarium oxysporum during submerged batch cultivation

    DEFF Research Database (Denmark)

    Topakas, E.; Christakopoulos, Paul

    2004-01-01

    Production of feruloyl esterases (FAEs) by Fusarium oxysporum was enhanced by optimization of initial pH of the culture medium, the type and concentration of nitrogen and carbon source. Submerged batch cultivation in a laboratory bioreactor (17 1) produced activity at 82 nkat g(-1) dry substrate....... Production of FAE does not therefore, require FA, however, production is diminished by the removal of esterified FA from the growth substrate. Optimal FAE activity was observed at pH 7 and 50 degreesC with 68 and 55% activity at pH 8 and pH 9, respectively. The esterase was fully stable at pH 5-8 and up...

  9. Dextran Utilization During Its Synthesis by Weissella cibaria RBA12 Can Be Overcome by Fed-Batch Fermentation in a Bioreactor.

    Science.gov (United States)

    Baruah, Rwivoo; Deka, Barsha; Kashyap, Niharika; Goyal, Arun

    2018-01-01

    Weissella cibaria RBA12 produced a maximum of 9 mg/ml dextran (with 90% efficiency) using shake flask culture under the optimized concentration of medium components viz. 2% (w/v) of each sucrose, yeast extract, and K 2 HPO 4 after incubation at optimized conditions of 20 °C and 180 rpm for 24 h. The optimized medium and conditions were used for scale-up of dextran production from Weissella cibaria RBA12 in 2.5-l working volume under batch fermentation in a bioreactor that yielded a maximum of 9.3 mg/ml dextran (with 93% efficiency) at 14 h. After 14 h, dextran produced was utilized by the bacterium till 18 h in its stationary phase under sucrose depleted conditions. Dextran utilization was further studied by fed-batch fermentation using sucrose feed. Dextran on production under fed-batch fermentation in bioreactor gave 35.8 mg/ml after 32 h. In fed-batch mode, there was no decrease in dextran concentration as observed in the batch mode. This showed that the utilization of dextran by Weissella cibaria RBA12 is initiated when there is sucrose depletion and therefore the presence of sucrose can possibly overcome the dextran hydrolysis. This is the first report of utilization of dextran, post-sucrose depletion by Weissella sp. studied in bioreactor.

  10. Continuous Heterogeneous Photocatalysis in Serial Micro-Batch Reactors.

    Science.gov (United States)

    Pieber, Bartholomäus; Shalom, Menny; Antonietti, Markus; Seeberger, Peter H; Gilmore, Kerry

    2018-01-29

    Solid reagents, leaching catalysts, and heterogeneous photocatalysts are commonly employed in batch processes but are ill-suited for continuous-flow chemistry. Heterogeneous catalysts for thermal reactions are typically used in packed-bed reactors, which cannot be penetrated by light and thus are not suitable for photocatalytic reactions involving solids. We demonstrate that serial micro-batch reactors (SMBRs) allow for the continuous utilization of solid materials together with liquids and gases in flow. This technology was utilized to develop selective and efficient fluorination reactions using a modified graphitic carbon nitride heterogeneous catalyst instead of costly homogeneous metal polypyridyl complexes. The merger of this inexpensive, recyclable catalyst and the SMBR approach enables sustainable and scalable photocatalysis. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Optimal Operation of Industrial Batch Crystallizers : A Nonlinear Model-based Control Approach

    NARCIS (Netherlands)

    Mesbah, A.

    2010-01-01

    Batch crystallization is extensively employed in the chemical, pharmaceutical, and food industries to separate and purify high value-added chemical substances. Despite their widespread application, optimal operation of batch crystallizers is particularly challenging. The difficulties primarily

  12. Comparison of Different Strategies for Selection/Adaptation of Mixed Microbial Cultures Able to Ferment Crude Glycerol Derived from Second-Generation Biodiesel

    Directory of Open Access Journals (Sweden)

    C. Varrone

    2015-01-01

    Full Text Available Objective of this study was the selection and adaptation of mixed microbial cultures (MMCs, able to ferment crude glycerol generated from animal fat-based biodiesel and produce building-blocks and green chemicals. Various adaptation strategies have been investigated for the enrichment of suitable and stable MMC, trying to overcome inhibition problems and enhance substrate degradation efficiency, as well as generation of soluble fermentation products. Repeated transfers in small batches and fed-batch conditions have been applied, comparing the use of different inoculum, growth media, and Kinetic Control. The adaptation of activated sludge inoculum was performed successfully and continued unhindered for several months. The best results showed a substrate degradation efficiency of almost 100% (about 10 g/L glycerol in 21 h and different dominant metabolic products were obtained, depending on the selection strategy (mainly 1,3-propanediol, ethanol, or butyrate. On the other hand, anaerobic sludge exhibited inactivation after a few transfers. To circumvent this problem, fed-batch mode was used as an alternative adaptation strategy, which led to effective substrate degradation and high 1,3-propanediol and butyrate production. Changes in microbial composition were monitored by means of Next Generation Sequencing, revealing a dominance of glycerol consuming species, such as Clostridium, Klebsiella, and Escherichia.

  13. Comparison of Different Strategies for Selection/Adaptation of Mixed Microbial Cultures Able to Ferment Crude Glycerol Derived from Second-Generation Biodiesel.

    Science.gov (United States)

    Varrone, C; Heggeset, T M B; Le, S B; Haugen, T; Markussen, S; Skiadas, I V; Gavala, H N

    2015-01-01

    Objective of this study was the selection and adaptation of mixed microbial cultures (MMCs), able to ferment crude glycerol generated from animal fat-based biodiesel and produce building-blocks and green chemicals. Various adaptation strategies have been investigated for the enrichment of suitable and stable MMC, trying to overcome inhibition problems and enhance substrate degradation efficiency, as well as generation of soluble fermentation products. Repeated transfers in small batches and fed-batch conditions have been applied, comparing the use of different inoculum, growth media, and Kinetic Control. The adaptation of activated sludge inoculum was performed successfully and continued unhindered for several months. The best results showed a substrate degradation efficiency of almost 100% (about 10 g/L glycerol in 21 h) and different dominant metabolic products were obtained, depending on the selection strategy (mainly 1,3-propanediol, ethanol, or butyrate). On the other hand, anaerobic sludge exhibited inactivation after a few transfers. To circumvent this problem, fed-batch mode was used as an alternative adaptation strategy, which led to effective substrate degradation and high 1,3-propanediol and butyrate production. Changes in microbial composition were monitored by means of Next Generation Sequencing, revealing a dominance of glycerol consuming species, such as Clostridium, Klebsiella, and Escherichia.

  14. Optimization of the liquid biofertilizer production in batch fermentation with by-product from MSG

    Science.gov (United States)

    Namfon, Panjanapongchai; Ratchanok, Sahaworarak; Chalida, Daengbussade

    2017-03-01

    The long term use of chemical fertilizers destroyed the friability of soil which obviously decreased quantity and quality of crops and especially affect microorganisms living in soils. The bio-fertilizer with microbial consortium is an environmental friendly alternative to solve this bottleneck due to harboring soil microorganisms such as Bacillus sp., Micrococcus sp., Pseudomonas sp., Staphylococcus sp. and Deinococcus sp. produced with natural by-product or waste from industries that is alternative and sustainable such as nutrient-rich (by-product) from Mono Sodium Glutamate (MSG) for producing liquid biofertilizer by batch fermentation. In this work, the concentration of reducing sugar from substrate as main carbon source was evaluated in shake flask with mixed cultures. The optimal conditions were studied comparing with two levels of reducing sugar concentration (10, 20 g/L) and inoculums concentration (10, 20 %v/v) with using (2×2) full factorial design. The results indicated that the by-product from monosodium glutamate is feasible for fermentation and inoculums concentration is mainly influenced the batch fermentation process. Moreover, the combined 20 g/L and 10%v/v were considerably concluded as an optimal condition, of which the concentration of vegetative cells and spores attained at 8.29×109 CFU/mL and 1.97×105 CFU/mL, respectively. Their spores cell yields from reducing sugar (Yx/s) were obtained at 1.22×106 and 3.34×105 CFU/g were markedly different. In conclusion, the liquid Biofertilizer was produced satisfactorily at 20 g/L reducing sugar and 10% v/v inoculums in shake flask culture. Moreover, these results suggested that the by-product from monosodium glutamate is feasible for low-cost substrate in economical scale and environmental-friendly.

  15. A parallel ILP algorithm that incorporates incremental batch learning

    OpenAIRE

    Nuno Fonseca; Rui Camacho; Fernado Silva

    2003-01-01

    In this paper we tackle the problems of eciency and scala-bility faced by Inductive Logic Programming (ILP) systems. We proposethe use of parallelism to improve eciency and the use of an incrementalbatch learning to address the scalability problem. We describe a novelparallel algorithm that incorporates into ILP the method of incremen-tal batch learning. The theoretical complexity of the algorithm indicatesthat a linear speedup can be achieved.

  16. Automated handling for SAF batch furnace and chemistry analysis operations

    International Nuclear Information System (INIS)

    Bowen, W.W.; Sherrell, D.L.; Wiemers, M.J.

    1981-01-01

    The Secure Automated Fabrication Program is developing a remotely operated breeder reactor fuel pin fabrication line. The equipment will be installed in the Fuels and Materials Examination Facility being constructed at Hanford, Washington. Production is scheduled to start in mid-1986. The application of small pneumatically operated industrial robots for loading and unloading product into and out of batch furnaces and for distribution and handling of chemistry samples is described

  17. Integration of virtualized worker nodes in standard batch systems

    International Nuclear Information System (INIS)

    Buege, Volker; Kunze, Marcel; Oberst, Oliver; Quast, Guenter; Scheurer, Armin; Hessling, Hermann; Kemp, Yves; Synge, Owen

    2010-01-01

    Current experiments in HEP only use a limited number of operating system flavours. Their software might only be validated on one single OS platform. Resource providers might have other operating systems of choice for the installation of the batch infrastructure. This is especially the case if a cluster is shared with other communities, or communities that have stricter security requirements. One solution would be to statically divide the cluster into separated sub-clusters. In such a scenario, no opportunistic distribution of the load can be achieved, resulting in a poor overall utilization efficiency. Another approach is to make the batch system aware of virtualization, and to provide each community with its favoured operating system in a virtual machine. Here, the scheduler has full flexibility, resulting in a better overall efficiency of the resources. In our contribution, we present a lightweight concept for the integration of virtual worker nodes into standard batch systems. The virtual machines are started on the worker nodes just before jobs are executed there. No meta-scheduling is introduced. We demonstrate two prototype implementations, one based on the Sun Grid Engine (SGE), the other using Maui/Torque as a batch system. Both solutions support local job as well as Grid job submission. The hypervisors currently used are Xen and KVM, a port to another system is easily envisageable. To better handle different virtual machines on the physical host, the management solution VmImageManager is developed. We will present first experience from running the two prototype implementations. In a last part, we will show the potential future use of this lightweight concept when integrated into high-level (i.e. Grid) work-flows.

  18. Hydrothermal liquefaction of biomass: Developments from batch to continuous process

    OpenAIRE

    Elliott, DC; Biller, P; Ross, AB; Schmidt, AJ; Jones, SB

    2015-01-01

    This review describes the recent results in hydrothermal liquefaction (HTL) of biomass in continuous-flow processing systems. Although much has been published about batch reactor tests of biomass HTL, there is only limited information yet available on continuous-flow tests, which can provide a more reasonable basis for process design and scale-up for commercialization. High-moisture biomass feedstocks are the most likely to be used in HTL. These materials are described and results of their pr...

  19. Batch production of microchannel plate photo-multipliers

    Energy Technology Data Exchange (ETDEWEB)

    Frisch, Henry J.; Wetstein, Matthew; Elagin, Andrey

    2018-03-06

    In-situ methods for the batch fabrication of flat-panel micro-channel plate (MCP) photomultiplier tube (PMT) detectors (MCP-PMTs), without transporting either the window or the detector assembly inside a vacuum vessel are provided. The method allows for the synthesis of a reflection-mode photocathode on the entrance to the pores of a first MCP or the synthesis of a transmission-mode photocathode on the vacuum side of a photodetector entrance window.

  20. BATCH PROCESS INTEGRATION OF APPLYING TECHNOLOGY OF ACID CARMINIC PINCH

    OpenAIRE

    Erazo E., Raymundo; Cárdenas R., Jorge L.; Woolcott H., Juan C.

    2014-01-01

    This work was developed in order to implement the PINCH technology integration batch process for carminic acid. The method used consisted of the application of the concepts of bottle necks total process (OPB) together with part-time models (TAM) and time fractionated! (TSM). The drying operation is identified as the rate limiting step of the process identifying it as an OPB plant capacity. The extraction yield was 95% w / p carminic acid with an energy savings of approximately 60% of the...

  1. Copper solubility in DWPF, Batch 1 waste glass: Update report

    International Nuclear Information System (INIS)

    Schumacker, R.F.

    1992-01-01

    The ''Late Washing'' Step in the processing of precipitate will require the use of additional copper formate in the Precipitate Reactor to catalyze the hydrolysis reaction. The increased copper concentration in the melter feed increases the potential for metal precipitation during the vitrification of the melter feed. This report describes recent results with a conservative glass selected from the DWPF acceptable region in the Batch 1 Variability Study

  2. Mixing volume determination in batch transfers through sonic detectors

    Energy Technology Data Exchange (ETDEWEB)

    Baptista, Renan Martins [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil). Centro de Pesquisas]. E-mail: renan@cenpes.petrobras.com.br; Rachid, Felipe Bastos de Freitas [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Engenharia Mecanica]. E-mail: rachid@mec.uff.br; Araujo, Jose Henrique Carneiro de [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Ciencia da Computacao]. E-mail: jhca@dcc.ic.uff.br

    2000-07-01

    An experimental methodology to evaluate mixing volumes in batch transfers by means of sonic detectors has been reported in this paper. Mixing volumes have then been computed in a transfer of diesel/gasoline carried out through a pipeline operated by Petrobras for different interface points. It has been shown that an adequate choice of the interface points is crucial for keeping the mixing volume uncertainty within acceptable limits. (author)

  3. On the track of fish batches in three distribution networks

    DEFF Research Database (Denmark)

    Randrup, Maria; Wu, Haiping; Jørgensen, Bo M.

    2012-01-01

    Three fish products sampled in retail shops were traced back to their origin and fish from the same batch were tracked forward towards the retailer, thereby simulating a recall situation. The resulting distribution networks were very complex, but to the extent that companies were willing to provi...... of discovering a fault as early as possible in order to minimise the costs of a recall. The localisation of distributed products during a recall operation can be facilitated by a well-constructed traceability system....

  4. Yields from pyrolysis of refinery residue using a batch process

    Directory of Open Access Journals (Sweden)

    S. Prithiraj

    2017-12-01

    Full Text Available Batch pyrolysis was a valuable process of assessing the potential of recovering and characterising products from hazardous waste materials. This research explored the pyrolysis of hydrocarbon-rich refinery residue, from crude oil processes, in a 1200 L electrically-heated batch retort. Furthermore, the off-gases produced were easily processed in compliance with existing regulatory emission standards. The methodology offers a novel, cost-effective and environmentally compliant method of assessing recovery potential of valuable products. The pyrolysis experiments yielded significant oil (70% with high calorific value (40 MJ/kg, char (14% with carbon content over 80% and non-condensable gas (6% with significant calorific value (240 kJ/mol. The final gas stream was subjected to an oxidative clean-up process with continuous on-line monitoring demonstrating compliance with South African emission standards. The gas treatment was overall economically optimal as only a smaller portion of the original residue was subjected to emission-controlling steps. Keywords: Batch pyrolysis, Volatiles, Oil yields, Char, Emissions, Oil recovery

  5. Treatment of slaughterhouse wastewater in anaerobic sequencing batch reactors

    Energy Technology Data Exchange (ETDEWEB)

    Masse, D. I.; Masse, L. [Agriculture and Agri-Food Canada, Lennoxville, PQ (Canada)

    2000-09-01

    Slaughterhouse waste water was treated in anaerobic sequencing batch reactors operated at 30 degrees C. Two of the batch reactors were seeded with anaerobic granular sludge from a milk processing plant reactor; two others received anaerobic non-granulated sludge from a municipal waste water treatment plant. Influent total chemical oxygen demand was reduced by 90 to 96 per cent at organic loading rates ranging from 2.07 kg to 4.93 kg per cubic meter. Reactors seeded with municipal sludge performed slightly better than those containing sludge from the milk processing plant. The difference was particularly noticeable during start-up, but the differences between the two sludges were reduced with time. The reactors produced a biogas containing 75 per cent methane. About 90.5 per cent of the chemical oxygen demand removed was methanized; volatile suspended solids accumulation was determined at 0.068 kg per kg of chemical oxygen demand removed. The high degree of methanization suggests that most of the soluble and suspended organic material in slaughterhouse waste water was degraded during the treatment in the anaerobic sequencing batch reactors. 30 refs., 1 tab., 6 figs.

  6. Automation of gamwave batch irradiator in Natal, South Africa

    International Nuclear Information System (INIS)

    Basson, J.K.; Basson, R.A.; Botha, J.

    1995-01-01

    High Energy Processing (HEPRO) has operated a Nordion JS 8200 Batch Irradiator for several years at Gamwave in Durban, South Africa. Product is loaded into aluminium totes and manually transported on trolleys into the irradiation chamber. Unirradiated totes are then exchanged with all the irradiated totes in the product pass mechanism, after which the source is raised and the batch irradiation process is started. Due to the inefficient Cobalt utilization experienced in this type of plant, it was decided to upgrade and automate the facility. This was done in what we believe is a simple and unique solution to the problem facing the future of such batch facilities. The design concept used for the Gamwave irradiator was based on irradiating product in carbons or bags of variable dimensions as per customer requirements. The intention was to convey product automatically in and out of the irradiation chamber eliminating the product change over downtime and thereby increasing source up utilization. Minor extensions were carried out to the Bioshield with the existing irradiator in full operation awaiting installation of the new source pass mechanism and conveyor system. Total plant shutdown for conversion to automation, including source reload and safety checks, was estimated to take ten days to fit the equipment. (author)

  7. Fault Diagnosis of Batch Reactor Using Machine Learning Methods

    Directory of Open Access Journals (Sweden)

    Sujatha Subramanian

    2014-01-01

    Full Text Available Fault diagnosis of a batch reactor gives the early detection of fault and minimizes the risk of thermal runaway. It provides superior performance and helps to improve safety and consistency. It has become more vital in this technical era. In this paper, support vector machine (SVM is used to estimate the heat release (Qr of the batch reactor both normal and faulty conditions. The signature of the residual, which is obtained from the difference between nominal and estimated faulty Qr values, characterizes the different natures of faults occurring in the batch reactor. Appropriate statistical and geometric features are extracted from the residual signature and the total numbers of features are reduced using SVM attribute selection filter and principle component analysis (PCA techniques. artificial neural network (ANN classifiers like multilayer perceptron (MLP, radial basis function (RBF, and Bayes net are used to classify the different types of faults from the reduced features. It is observed from the result of the comparative study that the proposed method for fault diagnosis with limited number of features extracted from only one estimated parameter (Qr shows that it is more efficient and fast for diagnosing the typical faults.

  8. Impact of Sterile Compounding Batch Frequency on Pharmaceutical Waste.

    Science.gov (United States)

    Abbasi, Ghalib; Gay, Evan

    2017-01-01

    Purpose: To measure the impact of increasing sterile compounding batch frequency on pharmaceutical waste as it relates to cost and quantity. Methods: Pharmaceutical IV waste at a tertiary care hospital was observed and recorded for 7 days. The batching frequency of compounded sterile products (CSPs) was then increased from twice daily to 4 times daily. After a washout period, pharmaceutical IV waste was then recorded for another 7 days. The quantity of units wasted and the cost were compared between both phases to determine the impact that batching frequency has on IV waste, specifically among high- and low-cost drugs. Results: Patient days increased from 2,459 during phase 1 to 2,617 during phase 2. The total number of CSPs wasted decreased from 3.6 to 2.7 doses per 100 patient days. Overall cost was reduced from $4,585.36 in phase 1 to $4,453.88 in phase 2. The value of wasted high-cost drugs per 100 patient days increased from $146 in phase 1 to $149 in phase 2 ( p > .05). The value of wasted low cost drugs per 100 patient days decreased from $41 in phase 1 to $21 in phase 2 ( p waste quantity and cost. The highest impact of the intervention was observed among low-cost CSPs.

  9. Analyzing data flows of WLCG jobs at batch job level

    Science.gov (United States)

    Kuehn, Eileen; Fischer, Max; Giffels, Manuel; Jung, Christopher; Petzold, Andreas

    2015-05-01

    With the introduction of federated data access to the workflows of WLCG, it is becoming increasingly important for data centers to understand specific data flows regarding storage element accesses, firewall configurations, as well as the scheduling of batch jobs themselves. As existing batch system monitoring and related system monitoring tools do not support measurements at batch job level, a new tool has been developed and put into operation at the GridKa Tier 1 center for monitoring continuous data streams and characteristics of WLCG jobs and pilots. Long term measurements and data collection are in progress. These measurements already have been proven to be useful analyzing misbehaviors and various issues. Therefore we aim for an automated, realtime approach for anomaly detection. As a requirement, prototypes for standard workflows have to be examined. Based on measurements of several months, different features of HEP jobs are evaluated regarding their effectiveness for data mining approaches to identify these common workflows. The paper will introduce the actual measurement approach and statistics as well as the general concept and first results classifying different HEP job workflows derived from the measurements at GridKa.

  10. Three-batch reloading scheme for IRIS reactor extended cycles

    International Nuclear Information System (INIS)

    Jecmenica, R.; Pevec, D.; Grgic, D.

    2004-01-01

    To fully exploit the IRIS reactor optimized maintenance, and at the same time improve fuel utilization, a core design enabling a 4-year operating cycle together with a three-batch reloading scheme is desirable. However, this requires not only the increased allowed burnup but also use of fuel with uranium oxide enriched beyond 5%. This paper considers three-batch reloading scheme for a 4-year operating cycle with the assumptions of increased discharge burnup and fuel enrichment beyond 5%. Calculational model of IRIS reactor core has been developed based on FER FA2D code for group constants generation and NRC's PARCS nodal code for global core analysis. Studies have been performed resulting in a preliminary design of a three-batch core configuration for the first cycle. It must be emphasized that this study is outside the current IRIS licensing efforts, which rely on the present fuel technology (enrichment below 5%), but it is of long-term interest for potential future IRIS design upgrades. (author)

  11. Some performance measures for vacation models with a batch Markovian arrival process

    Directory of Open Access Journals (Sweden)

    Sadrac K. Matendo

    1994-01-01

    Full Text Available We consider a single server infinite capacity queueing system, where the arrival process is a batch Markovian arrival process (BMAP. Particular BMAPs are the batch Poisson arrival process, the Markovian arrival process (MAP, many batch arrival processes with correlated interarrival times and batch sizes, and superpositions of these processes. We note that the MAP includes phase-type (PH renewal processes and non-renewal processes such as the Markov modulated Poisson process (MMPP.

  12. From batch to continuous extractive distillation using thermodynamic insight: class 1.0-2 case B

    OpenAIRE

    Shen, Weifeng; Benyounes, Hassiba; Gerbaud, Vincent

    2011-01-01

    A systematic feasibility analysis is presented for the separation azeotropic mixtures by batch and continuous extractive distillation. Based on batch feasibility knowledge, batch and continuous separation feasibility is studied under reflux ratio and entrainer flow-rate for the ternary system chloroform-vinyl acetate-butyl acetate, which belongs to the class 1.0-2 separating maximum boiling temperature azeotropes using a heavy entrainer. How information on feasibility of batch mode could be e...

  13. Comparative study of trapping parameters of LiF(TLD-100) from different production batches

    Energy Technology Data Exchange (ETDEWEB)

    Bos, A.J.J.; Piters, T.M.; Vries, W. de; Hoogenboom, J.E. (Delft Univ. of Technology (Netherlands). Interfaculty Reactor Institute)

    1990-01-01

    Computerised glow curve analysis has been used to determine the trapping parameters of the main peaks of the thermoluminescent (TL) material LiF(TLD-100). The TL material (solid state chips) originated from six different production batches with at least 19 chips per batch. The maxima of glow peaks 2 to 5 are found at the same temperature within very small limits. The activation energy and frequency factor of the main glow peak (peak 5) of TLD-100 originating from two batches differ significantly from those of the other four investigated batches. Nevertheless, the sensitivity of glow peak 5 is more or less the same for all batches. The trapping parameters of glow peaks 2 to 4 of TLD-100 vary little from batch to batch. The measured half-life of peak 2 differed strongly from batch to batch. For all investigated peaks no correlation has been found between glow peak sensitivity and trapping parameters. The results of this study suggest that both defect concentration and nature of the trapping centres vary from batch to batch. It would appear that as a consequence of selection by the manufacturer, the differences between the batches in terms of total light output are small. (author).

  14. An order batching algorithm for wave picking in a parallel-aisle warehouse

    NARCIS (Netherlands)

    Gademann, A.J.R.M.; Berg, van den J.P.; Hoff, van der H.H.

    2001-01-01

    In this paper we address the problem of batching orders in a parallel-aisle warehouse, with the objective to minimize the maximum lead time of any of the batches. This is a typical objective for a wave picking operation. Many heuristics have been suggested to solve order batching problems. We

  15. Look-ahead strategies for controlling batch operations in industry - overview, comparison and exploration

    NARCIS (Netherlands)

    Zee, D.J. van der; Harten, A. van; Schuur, P.C.; Joines, JA; Barton, RR; Kang, K; Fishwick, PA

    2000-01-01

    Batching jobs in a manufacturing system is a very common policy in most industries. The main reasons for batching are avoidance of set ups and/or facilitation of material handling. Good examples of batch-wise production systems are ovens found in aircraft industry and in semiconductor manufacturing.

  16. Look-ahead strategies for controlling batch operations in industry - An overview

    NARCIS (Netherlands)

    Zee, Durk-Jouke van der; Chick, SE; Sanchez, PJ; Ferrin, D; Morrice, DJ

    2003-01-01

    Batching jobs in a manufacturing system is a very common policy in most industries. Main reasons for batching are avoidance of set ups and/or facilitation of material handling. Examples of batch-wise production systems are ovens found in aircraft industry and in semiconductor manufacturing. Starting

  17. 40 CFR 63.487 - Batch front-end process vents-reference control technology.

    Science.gov (United States)

    2010-07-01

    ... § 63.487 Batch front-end process vents—reference control technology. (a) Batch front-end process vents... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Batch front-end process vents-reference control technology. 63.487 Section 63.487 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  18. Monitoring a PVC batch process with multivariate statistical process control charts

    NARCIS (Netherlands)

    Tates, A. A.; Louwerse, D. J.; Smilde, A. K.; Koot, G. L. M.; Berndt, H.

    1999-01-01

    Multivariate statistical process control charts (MSPC charts) are developed for the industrial batch production process of poly(vinyl chloride) (PVC). With these MSPC charts different types of abnormal batch behavior were detected on-line. With batch contribution plots, the probable causes of these

  19. Look-ahead strategies for controlling batch operations in industry : basic insights in rule construction

    NARCIS (Netherlands)

    van der Zee, D.J.; Sullivan, W.A.; Ahmad, M.M.; Fichtner, D.; Sauer, W.; Weigert, G.; Zerna, T.

    2002-01-01

    Batching jobs in a manufacturing system is a very common policy in most industries. Main reasons for batching are avoidance of set ups and/or facilitation of material handling. Examples of batch-wise production systems are ovens found in aircraft industry and in semiconductor manufacturing. Starting

  20. 40 CFR 63.1322 - Batch process vents-reference control technology.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Batch process vents-reference control technology. 63.1322 Section 63.1322 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Batch process vents—reference control technology. (a) Batch process vents. The owner or operator of a...

  1. Online learning in repeated auctions

    OpenAIRE

    Weed, Jonathan; Perchet, Vianney; Rigollet, Philippe

    2015-01-01

    Motivated by online advertising auctions, we consider repeated Vickrey auctions where goods of unknown value are sold sequentially and bidders only learn (potentially noisy) information about a good's value once it is purchased. We adopt an online learning approach with bandit feedback to model this problem and derive bidding strategies for two models: stochastic and adversarial. In the stochastic model, the observed values of the goods are random variables centered around the true value of t...

  2. A repeating fast radio burst.

    Science.gov (United States)

    Spitler, L G; Scholz, P; Hessels, J W T; Bogdanov, S; Brazier, A; Camilo, F; Chatterjee, S; Cordes, J M; Crawford, F; Deneva, J; Ferdman, R D; Freire, P C C; Kaspi, V M; Lazarus, P; Lynch, R; Madsen, E C; McLaughlin, M A; Patel, C; Ransom, S M; Seymour, A; Stairs, I H; Stappers, B W; van Leeuwen, J; Zhu, W W

    2016-03-10

    Fast radio bursts are millisecond-duration astronomical radio pulses of unknown physical origin that appear to come from extragalactic distances. Previous follow-up observations have failed to find additional bursts at the same dispersion measure (that is, the integrated column density of free electrons between source and telescope) and sky position as the original detections. The apparent non-repeating nature of these bursts has led to the suggestion that they originate in cataclysmic events. Here we report observations of ten additional bursts from the direction of the fast radio burst FRB 121102. These bursts have dispersion measures and sky positions consistent with the original burst. This unambiguously identifies FRB 121102 as repeating and demonstrates that its source survives the energetic events that cause the bursts. Additionally, the bursts from FRB 121102 show a wide range of spectral shapes that appear to be predominantly intrinsic to the source and which vary on timescales of minutes or less. Although there may be multiple physical origins for the population of fast radio bursts, these repeat bursts with high dispersion measure and variable spectra specifically seen from the direction of FRB 121102 support an origin in a young, highly magnetized, extragalactic neutron star.

  3. Ethanol production from Sorghum bicolor using both separate and simultaneous saccharification and fermentation in batch and fed batch systems

    DEFF Research Database (Denmark)

    Mehmood, Sajid; Gulfraz, M.; Rana, N. F.

    2009-01-01

    The objective of this work was to find the best combination of different experimental conditions during pre-treatment, enzymatic saccharification, detoxification of inhibitors and fermentation of Sorghum bicolor straw for ethanol production. The optimization of pre-treatment using different...... were used in order to increase the monomeric sugar during enzymatic hydrolysis and it has been observed that the addition of these surfactants contributed significantly in cellulosic conversion but no effect was shown on hemicellulosic hydrolysis. Fermentability of hydrolyzate was tested using...... Saccharomyces cerevisiae Ethanol Red (TM) and it was observed that simultaneous saccharification and fermentation ( SSF) with both batch and fed batch resulted in better ethanol yield as compared to separate hydrolysis and fermentation ( SHF). Detoxification of furan during SHF facilitated reduction...

  4. Kinetic studies on batch cultivation of Trichoderma reesei and application to enhance cellulase production by fed-batch fermentation.

    Science.gov (United States)

    Ma, Lijuan; Li, Chen; Yang, Zhenhua; Jia, Wendi; Zhang, Dongyuan; Chen, Shulin

    2013-07-20

    Reducing the production cost of cellulase as the key enzyme for cellulose hydrolysis to fermentable sugars remains a major challenge for biofuel production. Because of the complexity of cellulase production, kinetic modeling and mass balance calculation can be used as effective tools for process design and optimization. In this study, kinetic models for cell growth, substrate consumption and cellulase production in batch fermentation were developed, and then applied in fed-batch fermentation to enhance cellulase production. Inhibition effect of substrate was considered and a modified Luedeking-Piret model was developed for cellulase production and substrate consumption according to the growth characteristics of Trichoderma reesei. The model predictions fit well with the experimental data. Simulation results showed that higher initial substrate concentration led to decrease of cellulase production rate. Mass balance and kinetic simulation results were applied to determine the feeding strategy. Cellulase production and its corresponding productivity increased by 82.13% after employing the proper feeding strategy in fed-batch fermentation. This method combining mathematics and chemometrics by kinetic modeling and mass balance can not only improve cellulase fermentation process, but also help to better understand the cellulase fermentation process. The model development can also provide insight to other similar fermentation processes. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Butanol production from wheat straw by simultaneous saccharification and fermentation using Clostridium beijerinckii: Part II-Fed-batch fermentation

    International Nuclear Information System (INIS)

    Qureshi, Nasib; Saha, Badal C.; Cotta, Michael A.

    2008-01-01

    In these studies, Clostridium beijerinckii P260 was used to produce butanol (acetone-butanol-ethanol, or ABE) from wheat straw (WS) hydrolysate in a fed-batch reactor. It has been demonstrated that simultaneous hydrolysis of WS to achieve 100% hydrolysis to simple sugars (to the extent achievable under present conditions) and fermentation to butanol is possible. In addition to WS, the reactor was fed with a sugar solution containing glucose, xylose, arabinose, galactose, and mannose. The culture utilized all of the above sugars. It was noticed that near the end of fermentation (286-533 h), the culture had difficulties utilizing xylose. As a result of supplemental sugar feed to the reactor, ABE productivity was improved by 16% as compared with previous studies. In our previous experiment on simultaneous saccharification of WS and fermentation to butanol, a productivity of 0.31 g L -1 h -1 was observed, while in the present studies a productivity of 0.36 g L -1 h -1 was observed. It should be noted that a productivity of 0.77 g L -1 h -1 was observed when the culture was highly active. The fed-batch fermentation was operated for 533 h. It should be noted that C. beijerinckii P260 can be used to produce butanol from WS in integrated fermentations

  6. Glycerol as a Cheaper Carbon Source in Bacterial Cellulose (BC) Production by Gluconacetobacter Xylinus DSM46604 in Batch Fermentation System

    International Nuclear Information System (INIS)

    Azila Adnan; Nair, G.R.; Roslan Umar; Roslan Umar

    2015-01-01

    Bacterial cellulose (BC) is a polymer of glucose monomers, which has unique properties including high crystallinity and high strength. It has potential to be used in biomedical applications such as making artificial blood vessel, wound dressings, and in the paper making industry. Extensive study on BC aimed to improve BC production such as by using glycerol as a cheaper carbon source. BC was produced in shake flask culture using five different concentrations of glycerol (10, 20, 30, 40 and 50 g/ L). Using concentration of glycerol above 20 g/ L inhibited culture growth and BC production. Further experiments were performed in batch culture (3-L bioreactor) using 20 g/ L glycerol. It produced yield and productivity of 0.15 g/ g and 0.29 g/ L/ day BC, respectively. This is compared with the control medium, 50 g/ L glucose, which only gave yield and productivity of 0.05 g/ g and 0.23 g/ L/ day, respectively. Twenty g/ L of glycerol enhanced BC production by Gluconacetobacter xylinus DSM46604 in batch fermentation system. (author)

  7. Bioethanol production from starchy biomass by direct fermentation using saccharomyces diastaticus in batch free and immobilized cell systems

    Energy Technology Data Exchange (ETDEWEB)

    Kilonzo, P.M.; Margaritis, A. [University of Western Ontario, London, ON (Canada). Dept. of Chemical and Biochemical Engineering; Yu, J.; Ye, Q. [East China Univ. of Science and Technology, Shanghai (China). Biochemical Engineering Research Inst. and State Key Lab

    2006-07-01

    The feasibility of using amylolytic yeasts for the direct fermentation of starchy biomass to ethanol was discussed. Although amylolytic yeasts such as Saccharomycopsis, Lipomyces, and Schwaniomyces secrete both {alpha}-amylase and glucoamylase enzymes that synergistically enhance starch degradation, they are not suitable for industrial bio-ethanol production because of low tolerance for ethanol and slow fermentation rate. For that reason, this study examined the direct ethanol fermentation of soluble starch or dextrin with the amylolytic yeast Saccharomyces diastaticus in batch free and immobilized cells systems. Saccharomyces diastaticus secretes glucoamylase and can therefore assimilate and ferment starch and starch-like biomass. The main focus of the study was on parameters leading to higher ethanol yields from high concentration of dextrin and soluble starch using batch cultures. A natural attachment method was proposed in which polyurethane foam sheets were used as the carrier for amylolytic yeasts immobilization in ethanol fermentations. The support was chosen because it was inexpensive, autoclavable, pliable and could be tailored to suit process requirements regarding net surface charge, shape and size. It was found that Saccharomyces diastaticus was very efficient in terms of fermentation of high initial concentrations of dextrin or soluble starch. Higher concentrations of ethanol were produced. In batch fermentations, the cells fermented high dextrin concentrations more efficiently. In particular, in batch fermentation, more than 92 g-L of ethanol was produced from 240 g-L of dextrin, at conversion efficiency of 90 per cent. The conversion efficiency decreased to 60 per cent but a higher final ethanol concentration of 147 g/L was attained with a medium containing 500 g/L of dextrin. In an immobilized cell bioreactor, Saccharomyces diastaticus produced 83 g/L of ethanol from 240 g/L of dextrin, corresponding to ethanol volumetric productivity of 9.1 g

  8. Community dynamics of complex starter cultures for Gouda-type cheeses and its functional consequences

    NARCIS (Netherlands)

    Erkus, O.

    2014-01-01

    Lactic acid bacteria (LAB) are used as starter and adjunct cultures for the production of artisanal and industrial fermented milk products such as yoghurt and cheese. Artisanal fermentations is propagated with the transfer of an inoculum from old batch of fermented food to the new batch

  9. Influence of coal batch preparation on the quality of metallurgical соkе

    Directory of Open Access Journals (Sweden)

    Катерина Олегівна Шмельцер

    2015-10-01

    Full Text Available To study the influence of coal batch properties on coke strength we have considered the quality of the coke produced at the plant in Krivoy Rog from 2008 till 2012. Such factors as the large number of coal suppliers, imprecise selection of the optimal degree of batch crushing result in the decline in coke quality, the batch density and contents of the lean class (<0,5 mm are not optimum; poor blending of the batch after crushing; increased moisture and ash content of the coking batch; and extreme fluctuation in the coal and batch characteristics. It was found that high humidity of coal batch and its large fluctuations has most profound effect on the mechanical properties of coke. Under deteriorating resource base the quality of the coking batch preparation is important, To have batch of proper quality the following key aspects must be taken into account: the batch must be crushed to an optimum degree that will result in leaning components decrease and increased contents of vitrivite in it which improves the sinterability and coking, and hence the quality of coke; the degree of mixing of the coking batch in all indices must be up to 98-99%, for uneven distribution in the coal chamber worsens the quality of coke

  10. Improving repeatability by improving quality

    Energy Technology Data Exchange (ETDEWEB)

    Ronen, Shuki; Ackers, Mark; Schlumberger, Geco-Prakla; Brink, Mundy

    1998-12-31

    Time lapse (4-D) seismic is a promising tool for reservoir characterization and monitoring. The method is apparently simple: to acquire data repeatedly over the same reservoir, process and interpret the data sets, then changes between the data sets indicate changes in the reservoir. A problem with time lapse seismic data is that reservoirs are a relatively small part of the earth and important reservoir changes may cause very small differences to the time lapse data. The challenge is to acquire and process economical time lapse data such that reservoir changes can be detected above the noise of varying acquisition and environment. 7 refs., 9 figs.

  11. Coordinated hybrid automatic repeat request

    KAUST Repository

    Makki, Behrooz

    2014-11-01

    We develop a coordinated hybrid automatic repeat request (HARQ) approach. With the proposed scheme, if a user message is correctly decoded in the first HARQ rounds, its spectrum is allocated to other users, to improve the network outage probability and the users\\' fairness. The results, which are obtained for single- and multiple-antenna setups, demonstrate the efficiency of the proposed approach in different conditions. For instance, with a maximum of M retransmissions and single transmit/receive antennas, the diversity gain of a user increases from M to (J+1)(M-1)+1 where J is the number of users helping that user.

  12. Recommendation of ruthenium source for sludge batch flowsheet studies

    Energy Technology Data Exchange (ETDEWEB)

    Woodham, W. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-13

    Included herein is a preliminary analysis of previously-generated data from sludge batches 7a, 7b, 8, and 9 sludge simulant and real-waste testing, performed to recommend a form of ruthenium for future sludge batch simulant testing under the nitric-formic flowsheet. Focus is given to reactions present in the Sludge Receipt and Adjustment Tank cycle, given that this cycle historically produces the most changes in chemical composition during Chemical Process Cell processing. Data is presented and analyzed for several runs performed under the nitric-formic flowsheet, with consideration given to effects on the production of hydrogen gas, nitrous oxide gas, consumption of formate, conversion of nitrite to nitrate, and the removal and recovery of mercury during processing. Additionally, a brief discussion is given to the effect of ruthenium source selection under the nitric-glycolic flowsheet. An analysis of data generated from scaled demonstration testing, sludge batch 9 qualification testing, and antifoam degradation testing under the nitric-glycolic flowsheet is presented. Experimental parameters of interest under the nitric-glycolic flowsheet include N2O production, glycolate destruction, conversion of glycolate to formate and oxalate, and the conversion of nitrite to nitrate. To date, the number of real-waste experiments that have been performed under the nitric-glycolic flowsheet is insufficient to provide a complete understanding of the effects of ruthenium source selection in simulant experiments with regard to fidelity to real-waste testing. Therefore, a determination of comparability between the two ruthenium sources as employed under the nitric-glycolic flowsheet is made based on available data in order to inform ruthenium source selection for future testing under the nitric-glycolic flowsheet.

  13. Batch biomethanation of banana trash and coir path

    Energy Technology Data Exchange (ETDEWEB)

    Deivanai, K.; Bai, R.K. [Madurai Kamaraj Univ. (India)

    1995-08-01

    Anaerobic digestion of banana trash and coir pith was carried out for a period of one month by batch digestion. During biomethanation reduction of total- and volatile-solids was, respectively, 25.3 and 39.6% in banana trash and 13.6 and 21.6% in coir pith. A production of 9.22 l and 1.69 l (per kg TS added) of biogas with average methane content of 72 and 80% was achieved from banana trash and coir pith, respectively. (author)

  14. Batched Triangular DLA for Very Small Matrices on GPUs

    KAUST Repository

    Charara, Ali

    2017-03-13

    In several scientific applications, like tensor contractions in deep learning computation or data compression in hierarchical low rank matrix approximation, the bulk of computation typically resides in performing thousands of independent dense linear algebra operations on very small matrix sizes (usually less than 100). Batched dense linear algebra kernels are becoming ubiquitous for such scientific computations. Within a single API call, these kernels are capable of simultaneously launching a large number of similar matrix computations, removing the expensive overhead of multiple API calls while increasing the utilization of the underlying hardware.

  15. Online and Batch Supervised Background Estimation via L1 Regression

    KAUST Repository

    Dutta, Aritra

    2017-11-23

    We propose a surprisingly simple model for supervised video background estimation. Our model is based on $\\\\ell_1$ regression. As existing methods for $\\\\ell_1$ regression do not scale to high-resolution videos, we propose several simple and scalable methods for solving the problem, including iteratively reweighted least squares, a homotopy method, and stochastic gradient descent. We show through extensive experiments that our model and methods match or outperform the state-of-the-art online and batch methods in virtually all quantitative and qualitative measures.

  16. Online and Batch Supervised Background Estimation via L1 Regression

    KAUST Repository

    Dutta, Aritra; Richtarik, Peter

    2017-01-01

    We propose a surprisingly simple model for supervised video background estimation. Our model is based on $\\ell_1$ regression. As existing methods for $\\ell_1$ regression do not scale to high-resolution videos, we propose several simple and scalable methods for solving the problem, including iteratively reweighted least squares, a homotopy method, and stochastic gradient descent. We show through extensive experiments that our model and methods match or outperform the state-of-the-art online and batch methods in virtually all quantitative and qualitative measures.

  17. Simple multicomponent batch distillation procedure with a variable reflux policy

    Directory of Open Access Journals (Sweden)

    A. N. García

    2014-06-01

    Full Text Available This paper describes a shortcut procedure for batch distillation simulation with a variable reflux policy. The procedure starts from a shortcut method developed by Sundaram and Evans in 1993 and uses an iterative cycle to calculate the reflux ratio at each moment. The functional relationship between the concentrations at the bottom and the dome is evaluated using the Fenske equation and is complemented with the equations proposed by Underwood and Gilliland. The results of this procedure are consistent with those obtained using a fast method widely validated in the relevant literature.

  18. DISPATCHING CONTROL SYSTEM OF THE CONCRETE BATCHING PLANTS

    Directory of Open Access Journals (Sweden)

    Andrey Vladimirovich Ostroukh

    2015-09-01

    Full Text Available This paper proposes an approach to the design of dispatching control system of the concrete batching plant, which is a set of hardware maintenance, information, mathematical and software for control of technological objects. The proposed system is scalable and can include a control subsystem of mobile concrete plant, laboratory, subsystems, access control, and personnel management jobs. The system provides optimum automating the collection and processing of information for generating control signals and transmitting them without loss and distortion to the actuators in order to achieve the most efficient operation of process control object as a whole.

  19. Alanine repeats influence protein localization in splicing speckles and paraspeckles.

    Science.gov (United States)

    Chang, Shuo-Hsiu; Chang, Wei-Lun; Lu, Chia-Chen; Tarn, Woan-Yuh

    2014-12-16

    Mammalian splicing regulatory protein RNA-binding motif protein 4 (RBM4) has an alanine repeat-containing C-terminal domain (CAD) that confers both nuclear- and splicing speckle-targeting activities. Alanine-repeat expansion has pathological potential. Here we show that the alanine-repeat tracts influence the subnuclear targeting properties of the RBM4 CAD in cultured human cells. Notably, truncation of the alanine tracts redistributed a portion of RBM4 to paraspeckles. The alanine-deficient CAD was sufficient for paraspeckle targeting. On the other hand, alanine-repeat expansion reduced the mobility of RBM4 and impaired its splicing activity. We further took advantage of the putative coactivator activator (CoAA)-RBM4 conjoined splicing factor, CoAZ, to investigate the function of the CAD in subnuclear targeting. Transiently expressed CoAZ formed discrete nuclear foci that emerged and subsequently separated-fully or partially-from paraspeckles. Alanine-repeat expansion appeared to prevent CoAZ separation from paraspeckles, resulting in their complete colocalization. CoAZ foci were dynamic but, unlike paraspeckles, were resistant to RNase treatment. Our results indicate that the alanine-rich CAD, in conjunction with its conjoined RNA-binding domain(s), differentially influences the subnuclear localization and biogenesis of RBM4 and CoAZ. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  20. Ethanol Production from Whey by Kluyveromyces marxianus in Batch Fermentation System: Kinetics Parameters Estimation

    Directory of Open Access Journals (Sweden)

    Dessy Ariyanti

    2013-03-01

    Full Text Available Whey is the liquid remaining after milk has been curdled and strained. It is a by-product of the manufacture of cheese or casein and has several commercial uses. In environmental point of view, whey is kind of waste which has high pollution level due to it’s contain high organic compound with BOD and COD value 50 and 80 g/L respectively. On the other side, whey also contain an amount of lactose (4.5%-5%; lactose can be used as carbon source and raw material for producing ethanol via fermentation using yeast strain Kluyveromyces marxianus. The objective of this research is to investigate the ethanol production kinetics from crude whey through fermentation using Kluyveromyces marxianus and to predict the model kinetics parameter. The yeast was able to metabolize most of the lactose within 16 h to give 8.64 g/L ethanol, 4.43 g/L biomass, and remain the 3.122 g/L residual lactose. From the results presented it also can be concluded that common kinetic model for microbial growth, substrate consumption, and product formation is a good alternative to describe an experimental batch fermentation of Kluyveromyces marxianus grown on a medium composed of whey. The model was found to be capable of reflecting all batch culture phases to a certain degree of accuracy, giving the parameter value: μmax, Ks, YX/S, α, β : 0.32, 10.52, 0.095, 1.52, and 0.11 respectively. © 2013 BCREC UNDIP. All rights reserved(Selected Paper from International Conference on Chemical and Material Engineering (ICCME 2012Received: 27th September 2012; Revised: 29th November 2012; Accepted: 7th December 2012[How to Cite: D. Ariyanti, H. Hadiyanto, (2013. Ethanol Production from Whey by Kluyveromyces marxianus in Batch Fermentation System: Kinetics Parameters Estimation. Bulletin of Chemical Reaction Engineering & Catalysis, 7 (3: 179-184. (doi:10.9767/bcrec.7.3.4044.179-184][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.7.3.4044.179-184 ] View in  |

  1. Experimental analysis of distinct design of a batch solar water heater with integrated collector storage system

    Directory of Open Access Journals (Sweden)

    Varghese Jaji

    2007-01-01

    Full Text Available The performance of a new design of batch solar water heater has been studied. In this system, the collector and storage were installed in one unit. Unlike the conventional design consisting of small diameter water tubes, it has a single large diameter drum which serves the dual purpose of absorber tube and storage tank. In principle it is a compound parabolic collector. The drum is sized to have a storage capacity of 100 liter to serve a family of four persons. The tests were carried out with a single glass cover and two glass covers. The tests were repeated for several days. Performance analysis of the collector has revealed that it has maximum mean daily efficiency with two glass covers as high as 37.2%. The maximum water temperature in the storage tank of 60°C has been achieved for a clear day operation at an average solar beam radiation level of 680 W/m2 and ambient temperature of 32°C. To judge the operating characteristics and to synchronize utility pattern of the collector, the different parameters such as efficiency, mean plate temperature and mass flow rate has been investigated.

  2. Adsorption and desorption of radionuclide europium(III) on multiwalled carbon nanotubes studied by batch techniques

    International Nuclear Information System (INIS)

    Songsheng Lu; Junzheng Xu; Caicai Zhang; Zhiwei Niu

    2011-01-01

    The adsorption of Eu(III) on multiwalled carbon nanotubes (MWCNTs) as a function of pH, ionic strength and solid contents are studied by batch technique. The results indicate that the adsorption of Eu(III) on MWCNTs is strongly dependent on pH values, dependent on ionic strength at low pH values and independent of ionic strength at high pH values. Strong surface complexation and ion exchange contribute to the adsorption of Eu(III) on MWCNTs at low pH values, whereas surface complexation and surface precipitation are the main adsorption mechanism of Eu(III) on MWCNTs. The desorption of adsorbed Eu(III) from MWCNTs by adding HCl is also studied and the recycling use of MWCNTs in the removal of Eu(III) is investigated after the desorption of Eu(III) at low pH values. The results indicate that adsorbed Eu(III) can be easily desorbed from MWCNTs at low pH values, and MWCNTs can be repeatedly used to remove Eu(III) from aqueous solutions. MWCNTs are suitable material in the preconcentration and solidification of radionuclides from large volumes of aqueous solutions in nuclear waste management. (author)

  3. A procedure for batch separation of 14C-hexose from 14C-sucrose

    International Nuclear Information System (INIS)

    Tarpley, L.; Vietor, D.M.

    1991-01-01

    This presentation describes a method for separating 14 C-hexose from 14 C-sucrose in extracts of plant tissue. Portions of ethanol extracts are treated with activated charcoal in microcentrifuge tubes. Aliquots are removed, ethanol evaporated and replaced with reaction mixture that phosphorylates hexose (HEPPS, K 2 HPO 4 , Mg(C 2 H 3 O 2 ) 2 , ovalbumen, Na 2 ATP, yeast hexokinase). After a time course, the hexokinase reaction is stopped (slowed considerably) to minimize effects of contamination enzyme activities. The stopping agent used is lyxose, a nonphosphorylable analogue of glucose. The strong anionic charge of phosphate introduced through the hexokinase action results in binding (> 95%) of hexose-phosphate to anion-exchange resin. Sucrose remains unbound (> 95%) in solution. This batch ion-exchange is performed in microcentrifuge tubes to allow many samples to be processed simultaneously. Recovery of radiolabel in extracts is complete (99%), and determinations are repeatable (cv = 23%). This method for routinely separating and quantifying 14 C-hexose and 14 C-sucrose in plant tissue extracts can contribute to the economy and feasibility of studies of 14 C-photoassimilate partitioning to soluble sugars within and among plant tissues

  4. Efficient removal of Acid Green 25 dye from wastewater using activated Prunus Dulcis as biosorbent: Batch and column studies.

    Science.gov (United States)

    Jain, Suyog N; Gogate, Parag R

    2018-03-15

    Biosorbent synthesized from dead leaves of Prunus Dulcis with chemical activation during the synthesis was applied for the removal of Acid Green 25 dye from wastewater. The obtained biosorbent was characterized using Brunauer-Emmett-Teller analysis, Fourier transform-infrared spectroscopy and scanning electron microscopy measurements. It was demonstrated that alkali treatment during the synthesis significantly increased surface area of biosorbent from 67.205 to 426.346 m 2 /g. The effect of various operating parameters on dye removal was investigated in batch operation and optimum values of parameters were established as pH of 2, 14 g/L as the dose of natural biosorbent and 6 g/L as the dose of alkali treated biosorbent. Relative error values were determined to check fitting of obtained data to the different kinetic and isotherm models. It was established that pseudo-second order kinetic model and Langmuir isotherm fitted suitably to the obtained batch experimental data. Maximum biosorption capacity values were estimated as 22.68 and 50.79 mg/g for natural biosorbent and for alkali activated Prunus Dulcis, respectively. Adsorption was observed as endothermic and activation energy of 6.22 kJ/mol confirmed physical type of adsorption. Column experiments were also conducted to probe the effectiveness of biosorbent for practical applications in continuous operation. Breakthrough parameters were established by studying the effect of biosorbent height, flow rate of dye solution and initial dye concentration on the extent of dye removal. The maximum biosorption capacity under optimized conditions in the column operation was estimated as 28.57 mg/g. Thomas and Yoon-Nelson models were found to be suitably fitted to obtained column data. Reusability study carried out in batch and continuous column operations confirmed that synthesized biosorbent can be used repeatedly for dye removal from wastewater. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Kinetics and dynamic modelling of batch anaerobic digestion of municipal solid waste in a stirred reactor

    International Nuclear Information System (INIS)

    Nopharatana, Annop; Pullammanappallil, Pratap C.; Clarke, William P.

    2007-01-01

    A series of batch, slurry anaerobic digestion experiments were performed where the soluble and insoluble fractions, and unwashed MSW were separately digested in a 200 l stirred stainless steel vessel at a pH of 7.2 and a temperature of 38 deg. C. It was found that 7% of the total MSW COD was readily soluble, of which 80% was converted to biogas; 50% of the insoluble fraction was solubilised, of this only 80% was converted to biogas. The rate of digesting the insoluble fraction was about four times slower than the rate of digesting the soluble fraction; 48% of the total COD was converted to biogas and 40% of the total nitrogen was converted to ammonia. Soluble and insoluble fractions were broken down simultaneously. The minimum time to convert 95% of the degradable fraction to biogas was 20 days. The lag phase for the degradation of insoluble fraction of MSW can be overcome by acclimatising the culture with the soluble fraction. The rate of digestion and the methane yield was not affected by particle size (within the range of 2-50 mm). A dynamic model was developed to describe batch digestion of MSW. The parameters of the model were estimated using data from the separate digestion of soluble and insoluble fractions and validated against data from the digestion of unwashed MSW. Trends in the specific aceticlastic and formate-utilising methanogenic activity were used to estimate initial methanogenic biomass concentration and bacterial death rate coefficient. The kinetics of hydrolysis of insoluble fraction could be adequately described by a Contois equation and the kinetics of acidogenesis, and aceticlastic and hydrogen utilising methanogenesis by Monod equations

  6. Application of simple fed-batch technique to high-level secretory production of insulin precursor using Pichia pastoris with subsequent purification and conversion to human insulin

    Directory of Open Access Journals (Sweden)

    Chugh Dipti

    2010-05-01

    Full Text Available Abstract Background The prevalence of diabetes is predicted to rise significantly in the coming decades. A recent analysis projects that by the year 2030 there will be ~366 million diabetics around the world, leading to an increased demand for inexpensive insulin to make this life-saving drug also affordable for resource poor countries. Results A synthetic insulin precursor (IP-encoding gene, codon-optimized for expression in P. pastoris, was cloned in frame with the Saccharomyces cerevisiae α-factor secretory signal and integrated into the genome of P. pastoris strain X-33. The strain was grown to high-cell density in a batch procedure using a defined medium with low salt and high glycerol concentrations. Following batch growth, production of IP was carried out at methanol concentrations of 2 g L-1, which were kept constant throughout the remaining production phase. This robust feeding strategy led to the secretion of ~3 gram IP per liter of culture broth (corresponding to almost 4 gram IP per liter of cell-free culture supernatant. Using immobilized metal ion affinity chromatography (IMAC as a novel approach for IP purification, 95% of the secreted product was recovered with a purity of 96% from the clarified culture supernatant. Finally, the purified IP was trypsin digested, transpeptidated, deprotected and further purified leading to ~1.5 g of 99% pure recombinant human insulin per liter of culture broth. Conclusions A simple two-phase cultivation process composed of a glycerol batch and a constant methanol fed-batch phase recently developed for the intracellular production of the Hepatitis B surface antigen was adapted to secretory IP production. Compared to the highest previously reported value, this approach resulted in an ~2 fold enhancement of IP production using Pichia based expression systems, thus significantly increasing the efficiency of insulin manufacture.

  7. Nonparametric additive regression for repeatedly measured data

    KAUST Repository

    Carroll, R. J.; Maity, A.; Mammen, E.; Yu, K.

    2009-01-01

    We develop an easily computed smooth backfitting algorithm for additive model fitting in repeated measures problems. Our methodology easily copes with various settings, such as when some covariates are the same over repeated response measurements

  8. "Batch" kinetics in flow: online IR analysis and continuous control.

    Science.gov (United States)

    Moore, Jason S; Jensen, Klavs F

    2014-01-07

    Currently, kinetic data is either collected under steady-state conditions in flow or by generating time-series data in batch. Batch experiments are generally considered to be more suitable for the generation of kinetic data because of the ability to collect data from many time points in a single experiment. Now, a method that rapidly generates time-series reaction data from flow reactors by continuously manipulating the flow rate and reaction temperature has been developed. This approach makes use of inline IR analysis and an automated microreactor system, which allowed for rapid and tight control of the operating conditions. The conversion/residence time profiles at several temperatures were used to fit parameters to a kinetic model. This method requires significantly less time and a smaller amount of starting material compared to one-at-a-time flow experiments, and thus allows for the rapid generation of kinetic data. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Stormwater Pollution Prevention Plan - TA-60 Asphalt Batch Plant

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval, Leonard Frank [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-01-31

    This Storm Water Pollution Prevention Plan (SWPPP) was developed in accordance with the provisions of the Clean Water Act (33 U.S.C. §§1251 et seq., as amended), and the Multi-Sector General Permit for Storm Water Discharges Associated with Industrial Activity (U.S. EPA, June 2015) issued by the U.S. Environmental Protection Agency (EPA) for the National Pollutant Discharge Elimination System (NPDES) and using the industry specific permit requirements for Sector P-Land Transportation and Warehousing as a guide. This SWPPP applies to discharges of stormwater from the operational areas of the TA-60-01 Asphalt Batch Plant at Los Alamos National Laboratory. Los Alamos National Laboratory (also referred to as LANL or the “Laboratory”) is owned by the Department of Energy (DOE), and is operated by Los Alamos National Security, LLC (LANS). Throughout this document, the term “facility” refers to the TA-60 Asphalt Batch Plant and associated areas. The current permit expires at midnight on June 4, 2020.

  10. SEQUENCING BATCH REACTOR: A PROMISING TECHNOLOGY IN WASTEWATER TREATMENT

    Directory of Open Access Journals (Sweden)

    A. H. Mahvi

    2008-04-01

    Full Text Available Discharge of domestic and industrial wastewater to surface or groundwater is very dangerous to the environment. Therefore treatment of any kind of wastewater to produce effluent with good quality is necessary. In this regard choosing an effective treatment system is important. Sequencing batch reactor is a modification of activated sludge process which has been successfully used to treat municipal and industrial wastewater. The process could be applied for nutrients removal, high biochemical oxygen demand containing industrial wastewater, wastewater containing toxic materials such as cyanide, copper, chromium, lead and nickel, food industries effluents, landfill leachates and tannery wastewater. Of the process advantages are single-tank configuration, small foot print, easily expandable, simple operation and low capital costs. Many researches have been conducted on this treatment technology. The authors had been conducted some investigations on a modification of sequencing batch reactor. Their studies resulted in very high percentage removal of biochemical oxygen demand, chemical oxygen demand, total kjeldahl nitrogen, total nitrogen, total phosphorus and total suspended solids respectively. This paper reviews some of the published works in addition to experiences of the authors.

  11. Near infrared spectroscopy for qualitative comparison of pharmaceutical batches.

    Science.gov (United States)

    Roggo, Y; Roeseler, C; Ulmschneider, M

    2004-11-19

    Pharmaceuticals are produced according to current pharmacopoeias, which require quality parameters. Tablets of identical formulation, produced by different factories should have the same properties before and after storage. In this article, we analyzed samples having two different origins before and after storage (30 degrees C, 75% relative moisture). The aim of the study is to propose two approaches to understand the differences between origins and the storage effect by near infrared spectroscopy. In the first part, the main wavelengths are identified in transmittance and reflectance near infrared spectra in order to identify the major differences between the samples. In this paper, this approach is called fingerprinting. In the second part, principal component analysis (PCA) is computed to confirm the fingerprinting interpretation. The two interpretations show the differences between batches: physical aspect and moisture content. The manufacturing process is responsible for the physical differences between batches. During the storage, changes are due to the increase of moisture content and the decrease of the active content.

  12. Comparison of the release of constituents from granular materials under batch and column testing.

    Science.gov (United States)

    Lopez Meza, Sarynna; Garrabrants, Andrew C; van der Sloot, Hans; Kosson, David S

    2008-01-01

    Column leaching testing can be considered a better basis for assessing field impact data than any other available batch test method and thus provides a fundamental basis from which to estimate constituent release under a variety of field conditions. However, column testing is time-intensive compared to the more simplified batch testing, and may not always be a viable option when making decisions for material reuse. Batch tests are used most frequently as a simple tool for compliance or quality control reasons. Therefore, it is important to compare the release that occurs under batch and column testing, and establish conservative interpretation protocols for extrapolation from batch data when column data are not available. Five different materials (concrete, construction debris, aluminum recycling residue, coal fly ash and bottom ash) were evaluated via batch and column testing, including different column flow regimes (continuously saturated and intermittent unsaturated flow). Constituent release data from batch and column tests were compared. Results showed no significant difference between the column flow regimes when constituent release data from batch and column tests were compared. In most cases batch and column testing agreed when presented in the form of cumulative release. For arsenic in carbonated materials, however, batch testing underestimates the column constituent release for most LS ratios and also on a cumulative basis. For cases when As is a constituent of concern, column testing may be required.

  13. Topological characteristics of helical repeat proteins

    NARCIS (Netherlands)

    Groves, M R; Barford, D

    The recent elucidation of protein structures based upon repeating amino acid motifs, including the armadillo motif, the HEAT motif and tetratricopeptide repeats, reveals that they belong to the class of helical repeat proteins. These proteins share the common property of being assembled from tandem

  14. Digital storage of repeated signals

    International Nuclear Information System (INIS)

    Prozorov, S.P.

    1984-01-01

    An independent digital storage system designed for repeated signal discrimination from background noises is described. The signal averaging is performed off-line in the real time mode by means of multiple selection of the investigated signal and integration in each point. Digital values are added in a simple summator and the result is recorded the storage device with the volume of 1024X20 bit from where it can be output on an oscillograph, a plotter or transmitted to a compUter for subsequent processing. The described storage is reliable and simple device on one base of which the systems for the nuclear magnetic resonapce signal acquisition in different experiments are developed

  15. Hungarian repeat station survey, 2010

    Directory of Open Access Journals (Sweden)

    Péter Kovács

    2013-03-01

    Full Text Available The last Hungarian repeat station survey was completed between October 2010 and February 2011. Declination, inclination and the total field were observed using one-axial DMI fluxgate magnetometer mounted on Zeiss20A theodolite and GSM 19 Overhauser magnetometer. The magnetic elements of the sites were reduced to the epoch of 2010.5 on the basis of the continuous recordings of Tihany Geophysical Observatory. In stations located far from the reference observatory, the observations were carried out in the morning and afternoon in order to decrease the effect of the distant temporal correction. To further increase the accuracy, on-site dIdD variometer has also been installed near the Aggtelek station, in the Baradla cave, during the survey of the easternmost sites. The paper presents the technical details and the results of our last campaign. The improvement of the accuracy of the temporal reduction by the use of the local variometer is also reported.

  16. Linear Synchronous Motor Repeatability Tests

    International Nuclear Information System (INIS)

    Ward, C.R.

    2002-01-01

    A cart system using linear synchronous motors was being considered for the Plutonium Immobilization Plant (PIP). One of the applications in the PIP was the movement of a stack of furnace trays, filled with the waste form (pucks) from a stacking/unstacking station to several bottom loaded furnaces. A system was ordered to perform this function in the PIP Ceramic Prototype Test Facility (CPTF). This system was installed and started up in SRTC prior to being installed in the CPTF. The PIP was suspended and then canceled after the linear synchronous motor system was started up. This system was used to determine repeatability of a linear synchronous motor cart system for the Modern Pit Facility

  17. Two-dimensional quantum repeaters

    Science.gov (United States)

    Wallnöfer, J.; Zwerger, M.; Muschik, C.; Sangouard, N.; Dür, W.

    2016-11-01

    The endeavor to develop quantum networks gave rise to a rapidly developing field with far-reaching applications such as secure communication and the realization of distributed computing tasks. This ultimately calls for the creation of flexible multiuser structures that allow for quantum communication between arbitrary pairs of parties in the network and facilitate also multiuser applications. To address this challenge, we propose a two-dimensional quantum repeater architecture to establish long-distance entanglement shared between multiple communication partners in the presence of channel noise and imperfect local control operations. The scheme is based on the creation of self-similar multiqubit entanglement structures at growing scale, where variants of entanglement swapping and multiparty entanglement purification are combined to create high-fidelity entangled states. We show how such networks can be implemented using trapped ions in cavities.

  18. Hybrid FRC under repeated loading

    International Nuclear Information System (INIS)

    Komlos, K.; Babal, B.; Nuernbergerova, T.

    1993-01-01

    Fibre reinforced concretes (FRC) containing several volume fractions in different ratios of two types of fibres - polypropylene and steel, were tested under repeated loading. Mechanical properties of specimens - cubes 150/150/150 mm (for compressive strength), prisms 100/100/400 (for flexural strength), short cylinders 150/60 mm (for impact strength) have been experimentally investigated before and after cyclic loading at the age of 28 days curing time. Mix proportions were designed after DIN 1045 with max. aggregate size 8 mm and grading curve B 8. Portland Cement PC 400 in the amount of 450 kg. m -3 was applied and W/C ratio 0.55. Workability of mixes was measured by Vebe method and regulated by plasticizing admixture Ligoplast Na. Maximum hybrid fibre volume fraction (polypropylene + steel) was 1.0%. Dynamic forces generated in Schenck testing machine with frequency 16 Hz had sinusoidal wave form varying between 0.7 and 0.1 of static mechanical characteristics. The number of cycles in all tests was 10 5 . The residual MOR at static four point bending test and working diagram force-deflection was carried out as well. The impact properties after repeated loading in compression were tested by means of falling weight test. Relationships between composition of fibre composites with different combination of polypropylene (0.2, 0.3, 0.5% by volume) and steel (0.5, 0.7, and 0.8% by volume) fibre content were obtained and technological properties of mixes as well. (author)

  19. Quality control during repeated fryings

    Directory of Open Access Journals (Sweden)

    Cuesta, C.

    1998-08-01

    Full Text Available Most of the debate ¡s about how the slow or frequent turnover of fresh fat affects the deterioration, of fat used in frying. Then, the modification of different oils used in repeated fryings of potatoes without or with turnover of fresh oil, under similar frying conditions, was evaluated by two criteria: by measuring the total polar component isolated by column chromatography and by the evaluation of the specific compounds related to thermoxidative and hydrolytic alteration by High Performance Size Exclusion Chromatography (HPSEC. The results indicate that with frequent turnover of fresh oil, the critical level of 25% of polar material is rarely reached, and there are fewer problems with fat deterioration because the frying tended to increase the level of polar material and thermoxidative compounds (polymers and dimers of triglycerides and oxidized triglycerides in the fryer oil during the first fryings, followed by minor changes and a tendency to reach a near-steady state in successive fryings. However, in repeated frying of potatoes using a null turnover the alteration rate was higher being linear the relationship found between polar material or the different thermoxidative compounds and the number of fryings. On the other hand chemical reactions produced during deep-fat frying can be minimized by using proper oils. In addition the increased level of consumers awareness toward fat composition and its impact on human health could had an impact on the selection of fats for snacks and for industry. In this way monoenic fats are the most adequate from a nutritional point of view and for its oxidative stability during frying.

  20. Induction of secondary metabolism of Aspergillus terreus ATCC 20542 in the batch bioreactor cultures.

    Science.gov (United States)

    Boruta, Tomasz; Bizukojc, Marcin

    2016-04-01

    Cultivation of Aspergillus terreus ATCC 20542 in a stirred tank bioreactor was performed to induce the biosynthesis of secondary metabolites and provide the bioprocess-related insights into the metabolic capabilities of the investigated strain. The activation of biosynthetic routes was attempted by the diversification of process conditions and growth media. Several strategies were tested, including the addition of rapeseed oil or inulin, changing the concentration of nitrogen source, reduction of chlorine supply, cultivation under saline conditions, and using various aeration schemes. Fifteen secondary metabolites were identified in the course of the study by using ultra-high performance liquid chromatography coupled with mass spectrometry, namely mevinolinic acid, 4a,5-dihydromevinolinic acid, 3α-hydroxy-3,5-dihydromonacolin L acid, terrein, aspulvinone E, dihydroisoflavipucine, (+)-geodin, (+)-bisdechlorogeodin, (+)-erdin, asterric acid, butyrolactone I, desmethylsulochrin, questin, sulochrin, and demethylasterric acid. The study also presents the collection of mass spectra that can serve as a resource for future experiments. The growth in a salt-rich environment turned out to be strongly inhibitory for secondary metabolism and the formation of dense and compact pellets was observed. Generally, the addition of inulin, reducing the oxygen supply, and increasing the content of nitrogen source did not enhance the production of examined molecules. The most successful strategy involved the addition of rapeseed oil to the chlorine-deficient medium. Under these conditions, the highest levels of butyrolactone I, asterric acid, and mevinolinic acid were achieved and the presence of desmethylsulochrin and (+)-bisdechlorogeodin was detected in the broth. The constant and relatively high aeration rate in the idiophase was shown to be beneficial for terrein and (+)-geodin biosynthesis.

  1. Effect of culture conditions on lipase production by Fusarium solani in batch fermentation.

    Science.gov (United States)

    Maia, M M; Heasley, A; Camargo de Morais, M M; Melo, E H; Morais, M A; Ledingham, W M; Lima Filho, J L

    2001-01-01

    Lipase (Glycerol ester hydrolase EC 3.1.1.3.) from a Brazilian strain of Fusarium solani FSI has been investigated. The effect of different carbon sources and trace elements added to basal medium was observed with the aim of improving enzyme production. Lipase specific activity was highest (0.45 U mg(-1)) for sesame oil. When this medium was supplemented with trace elements using olive oil, corn oil and sesame oil the lipase specific activity increased to 0.86, 1.89 and 1.64 U mg(-1), respectively, after 96 h cultivation without any considerable biomass increase. The Km of this lipase using pNPP (p-nitrophenylpalmitate) as substrate, was 1.8 mM with a Vmax of 1.7 micromol min(-1) mg protein(-1). Lipase activity increased in the presence of increasing concentrations of hexane and toluene. In contrast, incubation of this enzyme with water-soluble solvents decreased its activity after 10% concentration (v/v) of the solvent. The lipase activity was stable below 35 degrees C but above this temperature activity losses were observed.

  2. Kinetic and energetic analysis of lipid accumulation in batch culture of Rhodotorula glutinis

    Energy Technology Data Exchange (ETDEWEB)

    Pan, J.G.; Rhee, J.S.

    1986-01-01

    Kinetic and energetic analyses were made to describe the accumulation of lipid Rhodotorula glutinis more quantitatively. Accumulation of lipid in yeast was controlled by kinetic factors. The energetic efficiency of lipid formation was higher than that of growth. 18 references.

  3. On the dynamics and constraints of batch culture growth of the cyanobacterium Cyanothece sp. ATCC 51142

    Czech Academy of Sciences Publication Activity Database

    Sinětova, Maria A.; Červený, Jan; Zavřel, Tomáš; Nedbal, Ladislav

    2012-01-01

    Roč. 162, č. 1 (2012), s. 148-155 ISSN 0168-1656 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Keywords : growth limitation * photoprotection * oscillations * Nitrogen fixation * microbial communication Subject RIV: EH - Ecology, Behaviour Impact factor: 3.183, year: 2012

  4. Citric acid production from hydrolysate of pretreated straw cellulose by Yarrowia lipolytica SWJ-1b using batch and fed-batch cultivation.

    Science.gov (United States)

    Liu, Xiaoyan; Lv, Jinshun; Zhang, Tong; Deng, Yuanfang

    2015-01-01

    In this study, crude cellulase produced by Trichoderma reesei Rut-30 was used to hydrolyze pretreated straw. After the compositions of the hydrolysate of pretreated straw were optimized, the study showed that natural components of pretreated straw without addition of any other components such as (NH4)2SO4, KH2PO4, or Mg(2+) were suitable for citric acid production by Yarrowia lipolytica SWJ-1b, and the optimal ventilatory capacity was 10.0 L/min/L medium. Batch and fed-batch production of citric acid from the hydrolysate of pretreated straw by Yarrowia lipolytica SWJ-1b has been investigated. In the batch cultivation, 25.4 g/L and 26.7 g/L citric acid were yields from glucose and hydrolysate of straw cellulose, respectively, while the cultivation time was 120 hr. In the three-cycle fed-batch cultivation, citric acid (CA) production was increased to 42.4 g/L and the cultivation time was extended to 240 hr. However, iso-citric acid (ICA) yield in fed-batch cultivation (4.0 g/L) was similar to that during the batch cultivation (3.9 g/L), and only 1.6 g/L of reducing sugar was left in the medium at the end of fed-batch cultivation, suggesting that most of the added carbon was used in the cultivation.

  5. Batch and multi-step fed-batch enzymatic saccharification of Formiline-pretreated sugarcane bagasse at high solid loadings for high sugar and ethanol titers.

    Science.gov (United States)

    Zhao, Xuebing; Dong, Lei; Chen, Liang; Liu, Dehua

    2013-05-01

    Formiline pretreatment pertains to a biomass fractionation process. In the present work, Formiline-pretreated sugarcane bagasse was hydrolyzed with cellulases by batch and multi-step fed-batch processes at 20% solid loading. For wet pulp, after 144 h incubation with cellulase loading of 10 FPU/g dry solid, fed-batch process obtained ~150 g/L glucose and ~80% glucan conversion, while batch process obtained ~130 g/L glucose with corresponding ~70% glucan conversion. Solid loading could be further increased to 30% for the acetone-dried pulp. By fed-batch hydrolysis of the dried pulp in pH 4.8 buffer solution, glucose concentration could be 247.3±1.6 g/L with corresponding 86.1±0.6% glucan conversion. The enzymatic hydrolyzates could be well converted to ethanol by a subsequent fermentation using Saccharomices cerevisiae with ethanol titer of 60-70 g/L. Batch and fed-batch SSF indicated that Formiline-pretreated substrate showed excellent fermentability. The final ethanol concentration was 80 g/L with corresponding 82.7% of theoretical yield. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Biological Treatment of Leachate using Sequencing Batch Reactor

    Directory of Open Access Journals (Sweden)

    WDMC Perera

    2014-12-01

    Full Text Available Normal 0 false false false EN-US X-NONE TA Abstract   In Sri Lanka municipal solid waste is generally disposed in poorly managed open dumps which lack liner systems and leachate collection systems. Rain water percolates through the waste layers to produce leachate which drains in to ground water and finally to nearby water bodies, degrading the quality of water. Leachate thus has become a major environmental concern in municipal waste management and treatment of leachate is a major challenge for the existing and proposed landfill sites.   The study was conducted to assess the feasibility of the usage of the Sequencing Batch Reactor in the treatment of the landfill leachate up to the proposed levels in the draft report of “Proposed Sri Lankan standard for landfill leachate to be disposed to the inland waters". Leachate collected from the open dumpsite at Meethotamulla, Western Province, Sri Lanka was used for leachate characterization.   SBR was constructed with a 10-liter working volume operated in an 18 hour cycle mode and each cycle consists of 15hours of aerobic, 2h settle and 0.5 h of fill/decant stages. The Dissolved Oxygen level within the SBR was maintained at 2 mg/l through the aerobic stage. Infeed was diluted with water during the acclimatization period and a leachate to water ratio of 55:45 was maintained. The removal efficiencies for different parameters were; COD (90.5%, BOD (92.6%, TS (92.1%, Conductivity (83.9%, Alkalinity (97.4%, Hardness (82.2%, Mg (80.5%, Fe (94.2%, Zn (63.4%, Cr (31.69%, Pb (99.6%, Sulphate (98.9%, and Phosphorus (71.4% respectively. In addition Ni and Cd were removed completely during a single SBR cycle. Thus the dilution of leachate in the dumpsites using municipal wastewater, groundwater or rainwater was identified as the most cost effective dilution methods. The effluent from the Sequencing batch reactor is proposed to be further treated using a constructed wetland before releasing to surface water.

  7. FLOWSHEET FOR ALUMINUM REMOVAL FROM SLUDGE BATCH 6

    International Nuclear Information System (INIS)

    Pike, J.; Gillam, J.

    2008-01-01

    Samples of Tank 12 sludge slurry show a substantially larger fraction of aluminum than originally identified in sludge batch planning. The Liquid Waste Organization (LWO) plans to formulate Sludge Batch 6 (SB6) with about one half of the sludge slurry in Tank 12 and one half of the sludge slurry in Tank 4. LWO identified aluminum dissolution as a method to mitigate the effect of having about 50% more solids in High Level Waste (HLW) sludge than previously planned. Previous aluminum dissolution performed in a HLW tank in 1982 was performed at approximately 85 C for 5 days and dissolved nearly 80% of the aluminum in the sludge slurry. In 2008, LWO successfully dissolved 64% of the aluminum at approximately 60 C in 46 days with minimal tank modifications and using only slurry pumps as a heat source. This report establishes the technical basis and flowsheet for performing an aluminum removal process in Tank 51 for SB6 that incorporates the lessons learned from previous aluminum dissolution evolutions. For SB6, aluminum dissolution process temperature will be held at a minimum of 65 C for at least 24 days, but as long as practical or until as much as 80% of the aluminum is dissolved. As planned, an aluminum removal process can reduce the aluminum in SB6 from about 84,500 kg to as little as 17,900 kg with a corresponding reduction of total insoluble solids in the batch from 246,000 kg to 131,000 kg. The extent of the reduction may be limited by the time available to maintain Tank 51 at dissolution temperature. The range of dissolution in four weeks based on the known variability in dissolution kinetics can range from 44 to more than 80%. At 44% of the aluminum dissolved, the mass reduction is approximately 1/2 of the mass noted above, i.e., 33,300 kg of aluminum instead of 66,600 kg. Planning to reach 80% of the aluminum dissolved should allow a maximum of 81 days for dissolution and reduce the allowance if test data shows faster kinetics. 47,800 kg of the dissolved

  8. The leucine-rich repeat structure.

    Science.gov (United States)

    Bella, J; Hindle, K L; McEwan, P A; Lovell, S C

    2008-08-01

    The leucine-rich repeat is a widespread structural motif of 20-30 amino acids with a characteristic repetitive sequence pattern rich in leucines. Leucine-rich repeat domains are built from tandems of two or more repeats and form curved solenoid structures that are particularly suitable for protein-protein interactions. Thousands of protein sequences containing leucine-rich repeats have been identified by automatic annotation methods. Three-dimensional structures of leucine-rich repeat domains determined to date reveal a degree of structural variability that translates into the considerable functional versatility of this protein superfamily. As the essential structural principles become well established, the leucine-rich repeat architecture is emerging as an attractive framework for structural prediction and protein engineering. This review presents an update of the current understanding of leucine-rich repeat structure at the primary, secondary, tertiary and quaternary levels and discusses specific examples from recently determined three-dimensional structures.

  9. A CATASTROPHIC-CUM-RESTORATIVE QUEUING SYSTEM WITH CORRELATED BATCH ARRIVALS AND VARIABLE CAPACITY

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar

    2008-07-01

    Full Text Available In this paper, we study a catastrophic-cum-restorative queuing system with correlated batch arrivals and service in batches of variable sizes. We perform the transient analysis of the queuing model. We obtain the Laplace Transform of the probability generating function of system size. Finally, some particular cases of the model have been derived and discussed. Keywords: Queue length, Catastrophes, Correlated batch arrivals, Broadband services, Variable service capacity, and Restoration.

  10. Queue Length and Server Content Distribution in an Infinite-Buffer Batch-Service Queue with Batch-Size-Dependent Service

    Directory of Open Access Journals (Sweden)

    U. C. Gupta

    2015-01-01

    Full Text Available We analyze an infinite-buffer batch-size-dependent batch-service queue with Poisson arrival and arbitrarily distributed service time. Using supplementary variable technique, we derive a bivariate probability generating function from which the joint distribution of queue and server content at departure epoch of a batch is extracted and presented in terms of roots of the characteristic equation. We also obtain the joint distribution of queue and server content at arbitrary epoch. Finally, the utility of analytical results is demonstrated by the inclusion of some numerical examples which also includes the investigation of multiple zeros.

  11. Aerobic degradation of petroleum refinery wastewater in sequential batch reactor.

    Science.gov (United States)

    Thakur, Chandrakant; Srivastava, Vimal C; Mall, Indra D

    2014-01-01

    The aim of the present work was to study the effect of various parameters affecting the treatment of raw petroleum refinery wastewater (PRW) having chemical oxygen demand (COD) of 350 mg L(-1) and total organic carbon (TOC) of 70 mg L(-1) in sequential batch reactor (SBR). Effect of hydraulic retention time (HRT) was studied in instantaneous fill condition. Maximum COD and TOC removal efficiencies were found to be 80% and 84%, respectively, for fill phase of 2 h and react phase of 2 h with fraction of SBR being filled with raw PRW in each cycle being 0.4. Effect of parameters was studied in terms of settling characteristic of treated slurry. Kinetics of treatment process has been studied. FTIR and UV-visible analysis of PRW before and after treatment have been performed so as to understand the degradation mechanism.

  12. Simulated annealing and joint manufacturing batch-sizing

    Directory of Open Access Journals (Sweden)

    Sarker Ruhul

    2003-01-01

    Full Text Available We address an important problem of a manufacturing system. The system procures raw materials from outside suppliers in a lot and processes them to produce finished goods. It proposes an ordering policy for raw materials to meet the requirements of a production facility. In return, this facility has to deliver finished products demanded by external buyers at fixed time intervals. First, a general cost model is developed considering both raw materials and finished products. Then this model is used to develop a simulated annealing approach to determining an optimal ordering policy for procurement of raw materials and also for the manufacturing batch size to minimize the total cost for meeting customer demands in time. The solutions obtained were compared with those of traditional approaches. Numerical examples are presented. .

  13. Batch fabrication of disposable screen printed SERS arrays.

    Science.gov (United States)

    Qu, Lu-Lu; Li, Da-Wei; Xue, Jin-Qun; Zhai, Wen-Lei; Fossey, John S; Long, Yi-Tao

    2012-03-07

    A novel facile method of fabricating disposable and highly reproducible surface-enhanced Raman spectroscopy (SERS) arrays using screen printing was explored. The screen printing ink containing silver nanoparticles was prepared and printed on supporting materials by a screen printing process to fabricate SERS arrays (6 × 10 printed spots) in large batches. The fabrication conditions, SERS performance and application of these arrays were systematically investigated, and a detection limit of 1.6 × 10(-13) M for rhodamine 6G could be achieved. Moreover, the screen printed SERS arrays exhibited high reproducibility and stability, the spot-to-spot SERS signals showed that the intensity variation was less than 10% and SERS performance could be maintained over 12 weeks. Portable high-throughput analysis of biological samples was accomplished using these disposable screen printed SERS arrays.

  14. Computer evaluation of the results of batch fermentations

    Energy Technology Data Exchange (ETDEWEB)

    Nyeste, L; Sevella, B

    1980-01-01

    A useful aid to the mathematical modeling of fermentation systems, for the kinetic evaluation of batch fermentations, is described. The generalized logistic equation may be used to describe the growth curves, substrate consumption, and product formation. A computer process was developed to fit the equation to experimental points, automatically determining the equation constants on the basis of the iteration algorithm of the method of non-linear least squares. By fitting the process to different master programs of various fermentations, the complex kinetic evaluation of fermentations becomes possible. Based on the analysis easily treatable generalized logistic equation, it is possible to calculate by computer different kinetic characteristics, e.g. rates, special rates, yields, etc. The possibility of committing subjective errors was reduced to a minimum. Employment of the method is demonstrated on some fermentation processes and problems arising in the course of application are discussed.

  15. Sequential batch anaerobic composting (SEBAC sup TM ) of solid wastes

    Energy Technology Data Exchange (ETDEWEB)

    Chynoweth, D.P.; O' Keefe, D.M.; Barkdoll, A.W.; Owens, J.M. (Department of Agricultural Engineering, University of Florida, Gainesville, Florida (US)); Legrand, R. (Radian Corporation, Austin, Texas (US))

    1992-01-01

    Anaerobic high-solids digestion (anaerobic composting) is an attractive option for treatment of organic wastes. The main advantages of anaerobic composting are the lack of aeration requirements and production of methane. An anaerobic composting design, sequential batch anaerobic composting (SEBAC{sup TM}), has been developed and demonstrated at the pilot scale which has proven to be stable and effective for treatment of the non-yeard waste and yard waste organic fractions of municipal solid waste (MSW). The design employs leachate recycle for wetting, inoculation, and removal of volatile organic acids during startup. Performance is similar to that of other designs requiring heavy solids inoculation and mixing and which do not have a mechanism for volatile organic acid removal during imbalance. (au) (12 refs.).

  16. Batch study of uranium biosorption by Elodea canadensis biomass

    International Nuclear Information System (INIS)

    Zheng-ji Yi; University of Science and Technology Beijing, Haidian District, Beijing; Jun Yao; Chinese University of Geosciences, Beijing; Mi-jia Zhu; Hui-lun Chen; Fei Wang; Zhi-min Yuan; Xing Liu

    2016-01-01

    The adsorption of U(VI) onto Elodea canadensis was studied via a batch equilibrium method. Kinetic investigation indicated that the U(VI) adsorption by E. canadensis reached an equilibrium in 120 min and followed pseudo-second-order kinetics. The solution pH was the most important parameter controlling adsorption of U(VI) and the optimum pH for U(VI) removal is 6.0. The U(VI) biosorption can be well described by Langmuir model. IR spectrum analysis revealed that -NH 2 , -OH, C=O and C-O could bind strongly with U(VI). XPS spectrum analysis implied that ion exchange and coordination mechanism could be involved in the U(VI) biosorption process. (author)

  17. Treatment of Laboratory Wastewater by Sequence Batch reactor technology

    International Nuclear Information System (INIS)

    Imtiaz, N.; Butt, M.; Khan, R.A.; Saeed, M.T.; Irfan, M.

    2012-01-01

    These studies were conducted on the characterization and treatment of sewage mixed with waste -water of research and testing laboratory (PCSIR Laboratories Lahore). In this study all the parameters COD, BOD and TSS etc of influent (untreated waste-water) and effluent (treated waste-water) were characterized using the standard methods of examination for water and waste-water. All the results of the analyzed waste-water parameters were above the National Environmental Quality Standards (NEQS) set at National level. Treatment of waste-water was carried out by conventional sequencing batch reactor technique (SBR) using aeration and settling technique in the same treatment reactor at laboratory scale. The results of COD after treatment were reduced from (90-95 %), BOD (95-97 %) and TSS (96-99 %) and the reclaimed effluent quality was suitable for gardening purposes. (author)

  18. Convolutional neural networks with balanced batches for facial expressions recognition

    Science.gov (United States)

    Battini Sönmez, Elena; Cangelosi, Angelo

    2017-03-01

    This paper considers the issue of fully automatic emotion classification on 2D faces. In spite of the great effort done in recent years, traditional machine learning approaches based on hand-crafted feature extraction followed by the classification stage failed to develop a real-time automatic facial expression recognition system. The proposed architecture uses Convolutional Neural Networks (CNN), which are built as a collection of interconnected processing elements to simulate the brain of human beings. The basic idea of CNNs is to learn a hierarchical representation of the input data, which results in a better classification performance. In this work we present a block-based CNN algorithm, which uses noise, as data augmentation technique, and builds batches with a balanced number of samples per class. The proposed architecture is a very simple yet powerful CNN, which can yield state-of-the-art accuracy on the very competitive benchmark algorithm of the Extended Cohn Kanade database.

  19. Analytical study plan: Shielded Cells batch 1 campaign; Revision 1

    International Nuclear Information System (INIS)

    Bibler, N.E.; Ha, B.C.; Hay, M.S.; Ferrara, D.M.; Andrews, M.K.

    1993-01-01

    Radioactive operations in the Defense Waste Processing Facility (DWPF) will require that the Savannah River Technology Center (SRTC) perform analyses and special studies with actual Savannah River Site (SRS) high-level waste sludge. SRS Tank 42 and Tank 51 will comprise the first batch of sludge to be processed in the DWPF. Approximately 25 liters of sludge from each of these tanks will be characterized and processed in the Shielded Cells of SRTC. During the campaign, processes will include sludge characterization, sludge washing, rheology determination, mixing, hydrogen evolution, feed preparation, and vitrification of the waste. To complete the campaign, the glass will be characterized to determine its durability and crystallinity. This document describes the types of samples that will be produced, the sampling schedule and analyses required, and the methods for sample and analytical control

  20. Transcriptional response of P. pastoris in fed-batch cultivations to Rhizopus oryzae lipase production reveals UPR induction

    Directory of Open Access Journals (Sweden)

    Valero Francisco

    2007-07-01

    Full Text Available Abstract Background The analysis of transcriptional levels of the genes involved in protein synthesis and secretion is a key factor to understand the host organism's responses to recombinant protein production, as well as their interaction with the cultivation conditions. Novel techniques such as the sandwich hybridization allow monitoring quantitatively the dynamic changes of specific RNAs. In this study, the transcriptional levels of some genes related to the unfolded protein response (UPR and central metabolism of Pichia pastoris were analysed during batch and fed-batch cultivations using an X-33-derived strain expressing a Rhizopus oryzae lipase under control of the formaldehyde dehydrogenase promoter (FLD1, namely the alcohol oxidase gene AOX1, the formaldehyde dehydrogenase FLD1, the protein disulfide isomerase PDI, the KAR2 gene coding for the BiP chaperone, the 26S rRNA and the R. oryzae lipase gene ROL. Results The transcriptional levels of the selected set of genes were first analysed in P. pastoris cells growing in shake flask cultures containing different carbon and nitrogen sources combinations, glycerol + ammonium, methanol + methylamine and sorbitol + methylamine. The transcriptional levels of the AOX1 and FLD1 genes were coherent with the known regulatory mechanism of C1 substrates in P. pastoris, whereas ROL induction lead to the up-regulation of KAR2 and PDI transcriptional levels, thus suggesting that ROL overexpression triggers the UPR. This was further confirmed in fed-batch cultivations performed at different growth rates. Transcriptional levels of the analysed set of genes were generally higher at higher growth rates. Nevertheless, when ROL was overexpressed in a strain having the UPR constitutively activated, significantly lower relative induction levels of these marker genes were detected. Conclusion The bead-based sandwich hybridization assay has shown its potential as a reliable instrument for quantification of

  1. Integrating PROOF Analysis in Cloud and Batch Clusters

    International Nuclear Information System (INIS)

    Rodríguez-Marrero, Ana Y; Fernández-del-Castillo, Enol; López García, Álvaro; Marco de Lucas, Jesús; Matorras Weinig, Francisco; González Caballero, Isidro; Cuesta Noriega, Alberto

    2012-01-01

    High Energy Physics (HEP) analysis are becoming more complex and demanding due to the large amount of data collected by the current experiments. The Parallel ROOT Facility (PROOF) provides researchers with an interactive tool to speed up the analysis of huge volumes of data by exploiting parallel processing on both multicore machines and computing clusters. The typical PROOF deployment scenario is a permanent set of cores configured to run the PROOF daemons. However, this approach is incapable of adapting to the dynamic nature of interactive usage. Several initiatives seek to improve the use of computing resources by integrating PROOF with a batch system, such as Proof on Demand (PoD) or PROOF Cluster. These solutions are currently in production at Universidad de Oviedo and IFCA and are positively evaluated by users. Although they are able to adapt to the computing needs of users, they must comply with the specific configuration, OS and software installed at the batch nodes. Furthermore, they share the machines with other workloads, which may cause disruptions in the interactive service for users. These limitations make PROOF a typical use-case for cloud computing. In this work we take profit from Cloud Infrastructure at IFCA in order to provide a dynamic PROOF environment where users can control the software configuration of the machines. The Proof Analysis Framework (PAF) facilitates the development of new analysis and offers a transparent access to PROOF resources. Several performance measurements are presented for the different scenarios (PoD, SGE and Cloud), showing a speed improvement closely correlated with the number of cores used.

  2. Optimal control of batch emulsion polymerization of vinyl chloride

    Energy Technology Data Exchange (ETDEWEB)

    Damslora, Andre Johan

    1998-12-31

    The highly exothermic polymerization of vinyl chloride (VC) is carried out in large vessels where the heat removal represents a major limitation of the production rate. Many emulsion polymerization reactors are operated in such a way that a substantial part of the heat transfer capacity is left unused for a significant part of the total batch time. To increase the reaction rate so that it matches the heat removal capacity during the course of the reaction, this thesis proposes the use of a sufficiently flexible initiator system to obtain a reaction rate which is high throughout the reaction and real-time optimization to compute the addition policy for the initiator. This optimization based approach provides a basis for an interplay between design and control and between production and research. A simple model is developed for predicting the polymerization rate. The model is highly nonlinear and open-loop unstable and may serve as an interesting case for comparison of nonlinear control strategies. The model is fitted to data obtained in a laboratory scale reactor. Finally, the thesis discusses optimal control of the emulsion polymerization reactor. Reduction of the batch cycle time is of major economic importance, as long as the quality parameters are within their specifications. The control parameterization had a major influence on the performance. A differentiable spline parameterization was applied and the optimization is illustrated in a number of cases. The best performance is obtained when the reactor temperature is obtained when the optimization is combined with some form of closed-loop control of the reactor temperature. 112 refs., 48 figs., 4 tabs.

  3. A Particle Batch Smoother Approach to Snow Water Equivalent Estimation

    Science.gov (United States)

    Margulis, Steven A.; Girotto, Manuela; Cortes, Gonzalo; Durand, Michael

    2015-01-01

    This paper presents a newly proposed data assimilation method for historical snow water equivalent SWE estimation using remotely sensed fractional snow-covered area fSCA. The newly proposed approach consists of a particle batch smoother (PBS), which is compared to a previously applied Kalman-based ensemble batch smoother (EnBS) approach. The methods were applied over the 27-yr Landsat 5 record at snow pillow and snow course in situ verification sites in the American River basin in the Sierra Nevada (United States). This basin is more densely vegetated and thus more challenging for SWE estimation than the previous applications of the EnBS. Both data assimilation methods provided significant improvement over the prior (modeling only) estimates, with both able to significantly reduce prior SWE biases. The prior RMSE values at the snow pillow and snow course sites were reduced by 68%-82% and 60%-68%, respectively, when applying the data assimilation methods. This result is encouraging for a basin like the American where the moderate to high forest cover will necessarily obscure more of the snow-covered ground surface than in previously examined, less-vegetated basins. The PBS generally outperformed the EnBS: for snow pillows the PBSRMSE was approx.54%of that seen in the EnBS, while for snow courses the PBSRMSE was approx.79%of the EnBS. Sensitivity tests show relative insensitivity for both the PBS and EnBS results to ensemble size and fSCA measurement error, but a higher sensitivity for the EnBS to the mean prior precipitation input, especially in the case where significant prior biases exist.

  4. Neurovascular Modeling: Small-Batch Manufacturing of Silicone Vascular Replicas

    Science.gov (United States)

    Chueh, J.Y.; Wakhloo, A.K.; Gounis, M.J.

    2009-01-01

    BACKGROUND AND PURPOSE Realistic, population based cerebrovascular replicas are required for the development of neuroendovascular devices. The objective of this work was to develop an efficient methodology for manufacturing realistic cerebrovascular replicas. MATERIALS AND METHODS Brain MR angiography data from 20 patients were acquired. The centerline of the vasculature was calculated, and geometric parameters were measured to describe quantitatively the internal carotid artery (ICA) siphon. A representative model was created on the basis of the quantitative measurements. Using this virtual model, we designed a mold with core-shell structure and converted it into a physical object by fused-deposit manufacturing. Vascular replicas were created by injection molding of different silicones. Mechanical properties, including the stiffness and luminal coefficient of friction, were measured. RESULTS The average diameter, length, and curvature of the ICA siphon were 4.15 ± 0.09 mm, 22.60 ± 0.79 mm, and 0.34 ± 0.02 mm-1 (average ± standard error of the mean), respectively. From these image datasets, we created a median virtual model, which was transformed into a physical replica by an efficient batch-manufacturing process. The coefficient of friction of the luminal surface of the replica was reduced by up to 55% by using liquid silicone rubber coatings. The modulus ranged from 0.67 to 1.15 MPa compared with 0.42 MPa from human postmortem studies, depending on the material used to make the replica. CONCLUSIONS Population-representative, smooth, and true-to-scale silicone arterial replicas with uniform wall thickness were successfully built for in vitro neurointerventional device-testing by using a batch-manufacturing process. PMID:19321626

  5. Retardation characteristics of radionuclides in geologic media through batch and packed column experiments

    International Nuclear Information System (INIS)

    Park, Hun Hwee; Han, Kyung Won; Han, Pil Soo; Lee, Jae Owan; Park, Chung Kyun; Yang, Ho Yeon

    1988-03-01

    Batch and packed column experiments are performed to investigate the retardation characteristics of radionuclide,i.e, Cs-137 in geologic media. In batch experiment, the effects of important parameters on the sorption of radionuclide in geologic media, such as nuclide concentration, pH, and particle size are examined. The Kd value obtained from breakthrough curve was compared with that from the batch sorption experiment to investigate the applicability of the Kd value from batch experiment to prediction of radionuclide migration in dynamic flow through porous media. The proposed model of radionuclide migration in porous media is also verified using the experimental results. (Author)

  6. Role of batch depletion of broiler houses on the occurrence of Campylobacter spp. in chicken flocks

    DEFF Research Database (Denmark)

    Hald, Birthe; Rattenborg, Erik; Madsen, Mogens

    2001-01-01

    Aims: The effect of batch depletion of broiler houses for campylobacter occurrence in broiler flocks was estimated in 10 flocks, each comprising a separate female and male batch. Methods and Results: The chicks were sampled first bq; cloacal swabs in the broiler houses before the start...... that batch depletion of broiler houses increased the prevalence of Campylobacter spp.-infected broilers in the flocks, that the introduction occurred a hen catching the first batch, and that campylobacter spreads through the entire flock within a week. Significance and Impact of the Study: The results from...

  7. Cell recycle batch fermentation of high-solid lignocellulose using a recombinant cellulase-displaying yeast strain for high yield ethanol production in consolidated bioprocessing.

    Science.gov (United States)

    Matano, Yuki; Hasunuma, Tomohisa; Kondo, Akihiko

    2013-05-01

    The aim of this study is to develop a scheme of cell recycle batch fermentation (CRBF) of high-solid lignocellulosic materials. Two-phase separation consisting of rough removal of lignocellulosic residues by low-speed centrifugation and solid-liquid separation enabled effective collection of Saccharomyces cerevisiae cells with decreased lignin and ash. Five consecutive batch fermentation of 200 g/L rice straw hydrothermally pretreated led to an average ethanol titer of 34.5 g/L. Moreover, the display of cellulases on the recombinant yeast cell surface increased ethanol titer to 42.2 g/L. After, five-cycle fermentation, only 3.3 g/L sugar was retained in the fermentation medium, because cellulase displayed on the cell surface hydrolyzed cellulose that was not hydrolyzed by commercial cellulases or free secreted cellulases. Fermentation ability of the recombinant strain was successfully kept during a five-cycle repeated batch fermentation with 86.3% of theoretical yield based on starting biomass. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. The outcome of infected total knee arthroplasty: culture-positive versus culture-negative.

    Science.gov (United States)

    Kim, Young-Hoo; Park, Jang-Won; Kim, Jun-Shik; Kim, Dong-Jin

    2015-10-01

    We studied the outcome in culture-positive and culture-negative infected total knee arthroplasty (TKA). We retrospectively reviewed 140 patients with culture-positive and 102 patients with culture-negative infected TKAs. We determined the infection control rate and clinical outcome after repeated debridement, and repeated 2-stage TKA in the culture-positive and culture-negative groups. The mean follow-up was 9.3 years (range 5-14 years) in the culture-positive group and 10.6 years (5-22) in the culture-negative group. The overall infection control rate was 56 % in both groups after the first treatment. The overall infection control rate was 90 % in the culture-positive group and 95 % in the culture-negative group. A functional knee was obtained in 90 % in the culture-positive group and 95 % in the culture-negative group. The data suggest that treatment according to the types of infection in both culture-positive and culture-negative groups after TKA controlled infection and maintained functional TKA with a firm level of fixation for most patients. Repeated debridement and repeated two-stage exchange TKA further improved infection control rates after the initial treatment and increased the likelihood of maintaining a functional TKA.

  9. Versatile modeling and optimization of fed batch processes for the production of secreted heterologous proteins with Pichia pastoris

    Directory of Open Access Journals (Sweden)

    Gasser Brigitte

    2006-12-01

    Full Text Available Abstract Background Secretion of heterologous proteins depends both on biomass concentration and on the specific product secretion rate, which in turn is not constant at varying specific growth rates. As fed batch processes usually do not maintain a steady state throughout the feed phase, it is not trivial to model and optimize such a process by mathematical means. Results We have developed a model for product accumulation in fed batch based on iterative calculation in Microsoft Excel spreadsheets, and used the Solver software to optimize the time course of the media feed in order to maximize the volumetric productivity. The optimum feed phase consisted of an exponential feed at maximum specific growth rate, followed by a phase with linearly increasing feed rate and consequently steadily decreasing specific growth rate. The latter phase could be modeled also by exact mathematical treatment by the calculus of variations, yielding the explicit shape of the growth function, however, with certain indeterminate parameters. To evaluate the latter, one needs a numerical optimum search algorithm. The explicit shape of the growth function provides additional evidence that the Excel model results in correct data. Experimental evaluation in two independent fed batch cultures resulted in a good correlation to the optimized model data, and a 2.2 fold improvement of the volumetric productivity. Conclusion The advantages of the procedure we describe here are the ease of use and the flexibility, applying software familiar to every scientist and engineer, and rapid calculation which makes predictions extremely easy, so that many options can be tested in silico quickly. Additional options like further biological and technological constraints or different functions for specific productivity and biomass yield can easily be integrated.

  10. Acceptance Test Data for Candidate AGR-5/6/7 TRISO Particle Batches BWXT Coater Batches 93165 93172 Defective IPyC Fraction and Pyrocarbon Anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Helmreich, Grant W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Skitt, Darren J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dyer, John A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Schumacher, Austin T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-03-01

    Coated particle fuel batches J52O-16-93165, 93166, 93168, 93169, 93170, and 93172 were produced by Babcock and Wilcox Technologies (BWXT) for possible selection as fuel for the Advanced Gas Reactor Fuel Development and Qualification (AGR) Program’s AGR-5/6/7 irradiation test in the Idaho National Laboratory (INL) Advanced Test Reactor (ATR). Some of these batches may alternately be used as demonstration coated particle fuel for other experiments. Each batch was coated in a 150-mm-diameter production-scale fluidized-bed chemical vapor deposition (CVD) furnace. Tristructural isotropic (TRISO) coatings were deposited on 425-μm-nominal-diameter spherical kernels from BWXT lot J52R-16-69317 containing a mixture of 15.5%-enriched uranium carbide and uranium oxide (UCO). The TRISO coatings consisted of four consecutive CVD layers: a ~50% dense carbon buffer layer with 100-μm-nominal thickness, a dense inner pyrolytic carbon (IPyC) layer with 40-μm-nominal thickness, a silicon carbide (SiC) layer with 35-μm-nominal thickness, and a dense outer pyrolytic carbon (OPyC) layer with 40-μmnominal thickness. The TRISO-coated particle batches were sieved to upgrade the particles by removing over-sized and under-sized material, and the upgraded batches were designated by appending the letter A to the end of the batch number (e.g., 93165A).

  11. Kinetic analysis and modeling of daptomycin batch fermentation by Streptomyces roseosporus.

    Science.gov (United States)

    Lu, Wenyu; Fan, Jinghua; Wen, Jianping; Xia, Zhendong; Caiyin, Qinggele

    2011-02-01

    In this study, Streptomyces roseosporus was subjected to helium-neon (He-Ne) laser (632.8 nm) irradiation to improve the production ability of extracellular antibiotic daptomycin. Under the optimum irradiation dosage of 18 mW for 22 min, a stable positive mutant strain S. roseosporus LC-54 was obtained. The maximum A21978C (daptomycin is a semisynthetic antimicrobial substance derived from the A21978C complex) yield of this mutant strain was 296 mg/l, which was 146% higher than that of the wild strain. The mutant strain grew more quickly and utilized carbohydrate sources more efficiently than the wild strain. The batch culture kinetics was investigated in a 7 l bioreactor. The logistic equation for growth, the Luedeking-Piret equation for daptomycin production, and Luedeking-Piret-like equations for carbon substrate consumption were established. This model appeared to provide a reasonable description for each parameter during the growth phase and fitted fairly well with the experiment data.

  12. Fed batch fermentation scale up in the production of recombinant streptokinase

    Directory of Open Access Journals (Sweden)

    Salvador Losada-Nerey

    2017-01-01

    Full Text Available Due to the high international demand of the recombinant streptokinase (Skr produced at the National Center for Bioproducts (BioCen, it was necessary to increase the production capacity of the drug, since the current production volume does not cover the demand. A scale up of the process of fermentation of the recombinant streptokinase was made using a fed batch culture, from the bank scale towards a 300L fermenter. The scaling criteria used were: the intensive variables of the process, the relationships of volumes of the fermentation medium and inoculum, the volumetric coefficient of oxygen transfer and air volume to liquid flow relationship which were kept constant. With this scale up procedure it was possible to reproduce the results obtained at the bank scale of and to double the biomass production volume with the same equipment, fulfilling all the quality requirements of the product and to cover the current demand of the market. Techno-economic indicators demonstrated the feasibility of this option.

  13. High repeatability from 3D experimental platform for quantitative analysis of cellular branch pattern formations.

    Science.gov (United States)

    Hagiwara, Masaya; Nobata, Rina; Kawahara, Tomohiro

    2018-04-24

    Three-dimensional (3D) cell and tissue cultures more closely mimic biological environments than two-dimensional (2D) cultures and are therefore highly desirable in culture experiments. However, 3D cultures often fail to yield repeatable experimental results because of variation in the initial culture conditions, such as cell density and distribution in the extracellular matrix, and therefore reducing such variation is a paramount concern. Here, we present a 3D culture platform that demonstrates highly repeatable experimental results, obtained by controlling the initial cell cluster shape in the gel cube culture device. A micro-mould with the desired shape was fabricated by photolithography or machining, creating a 3D pocket in the extracellular matrix contained in the device. Highly concentrated human bronchial epithelial cells were then injected in the pocket so that the cell cluster shape matched the fabricated mould shape. Subsequently, the cubic device supplied multi-directional scanning, enabling high-resolution capture of the whole tissue structure with only a low-magnification lens. The proposed device significantly improved the repeatability of the developed branch pattern, and multi-directional scanning enabled quantitative analysis of the developed branch pattern formations. A mathematical simulation was also conducted to reveal the mechanisms of branch pattern formation. The proposed platform offers the potential to accelerate any research field that conducts 3D culture experiments, including tissue regeneration and drug development.

  14. Aerobic biodegradation of organotin compounds in activated sludge batch reactors

    Energy Technology Data Exchange (ETDEWEB)

    Stasinakis, Athanasios S. [Department of Environmental Studies, Water and Air Quality Laboratory, University of the Aegean, University Hill, Mytilene 81 100 (Greece)]. E-mail: astas@env.aegean.gr; Thomaidis, Nikolaos S. [Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Zografou, Athens 157 71 (Greece); Nikolaou, Anastasia [Department of Environmental Studies, Water and Air Quality Laboratory, University of the Aegean, University Hill, Mytilene 81 100 (Greece); Kantifes, Andreas [Department of Environmental Studies, Water and Air Quality Laboratory, University of the Aegean, University Hill, Mytilene 81 100 (Greece)

    2005-04-01

    The biodegradation behavior of four organotin (OT) compounds, namely tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT) and triphenyltin (TPhT), was studied in lab-scale activated sludge batch reactors. The activated sludge was spiked with the OT compounds at a level of 100 {mu}g l{sup -1} as Sn. Determination of the OT compounds by GC-FPD after ethylation in the dissolved and particulate phase revealed that 24 h after the start of the experiments, almost the total of OT compounds has been removed from the dissolved phase and is associated with the suspended solids. Calculation of mass balance in batch reactors showed that OT compounds biodegradation was performed via a sequential dealkylation process. Removals due to biodegradation were differentiated according to the parent compound. In experiments with non-acclimatized biomass, a percentage of 27.1, 8.3, 73.8 and 51.3 was still present as TBT, DBT, MBT and TPhT, respectively, at the end of the experiment (18th day). Half-lives (t{sub 1/2}) of 10.2 and 5.1 days were calculated for TBT and DBT, respectively, whereas apparent t{sub 1/2} values could not be determined for MBT and TPhT (t{sub 1/2} > 18 days). The capacity of activated sludge to biodegrade OT compounds in the absence of supplemental substrate indicated that these compounds can be metabolized as single sources of carbon and energy in activated sludge systems. Excluding TBT, the presence of low concentrations of supplemental substrate did not affect the biodegradation potential of activated sludge. The acclimatization of biomass on OT compounds enhanced significantly biodegradation, resulting in significant decreases of half-lives of OT compounds. As a result in the presence of acclimatized biomass, half-lives of 1.4, 3.6, 9.8 and 5.0 days were calculated for TBT, DBT, MBT and TPhT, respectively. - The fate of organotins is assessed in activated sludge systems.

  15. Aerobic biodegradation of organotin compounds in activated sludge batch reactors

    International Nuclear Information System (INIS)

    Stasinakis, Athanasios S.; Thomaidis, Nikolaos S.; Nikolaou, Anastasia; Kantifes, Andreas

    2005-01-01

    The biodegradation behavior of four organotin (OT) compounds, namely tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT) and triphenyltin (TPhT), was studied in lab-scale activated sludge batch reactors. The activated sludge was spiked with the OT compounds at a level of 100 μg l -1 as Sn. Determination of the OT compounds by GC-FPD after ethylation in the dissolved and particulate phase revealed that 24 h after the start of the experiments, almost the total of OT compounds has been removed from the dissolved phase and is associated with the suspended solids. Calculation of mass balance in batch reactors showed that OT compounds biodegradation was performed via a sequential dealkylation process. Removals due to biodegradation were differentiated according to the parent compound. In experiments with non-acclimatized biomass, a percentage of 27.1, 8.3, 73.8 and 51.3 was still present as TBT, DBT, MBT and TPhT, respectively, at the end of the experiment (18th day). Half-lives (t 1/2 ) of 10.2 and 5.1 days were calculated for TBT and DBT, respectively, whereas apparent t 1/2 values could not be determined for MBT and TPhT (t 1/2 > 18 days). The capacity of activated sludge to biodegrade OT compounds in the absence of supplemental substrate indicated that these compounds can be metabolized as single sources of carbon and energy in activated sludge systems. Excluding TBT, the presence of low concentrations of supplemental substrate did not affect the biodegradation potential of activated sludge. The acclimatization of biomass on OT compounds enhanced significantly biodegradation, resulting in significant decreases of half-lives of OT compounds. As a result in the presence of acclimatized biomass, half-lives of 1.4, 3.6, 9.8 and 5.0 days were calculated for TBT, DBT, MBT and TPhT, respectively. - The fate of organotins is assessed in activated sludge systems

  16. Batch and continuous extraction of bromelain enzyme by reversed micelles

    Directory of Open Access Journals (Sweden)

    Ana Maria Frattini Fileti

    2009-10-01

    Full Text Available The main aim of this study was to optimize the conditions for bromelain extraction by reversed micelles from pineapple juice (Ananas comosus. The purification was carried out in batch extraction and a micro-column with pulsed caps for continuous extraction. The cationic micellar solution was made of BDBAC as a surfactant, isooctane as a solvent and hexanol as a co-solvent. For the batch process, a purification factor of 3 times at the best values of surfactant agent, co-solvent and salt concentrations, pH of the back and forward extractions were, 100 mM, 10% v/v, 1 M, 3.5 and 8, respectively. For the continuous operation, independent variables optimal point was determined: ratio between light phase flow rate and total flow rate equal to 0.67 and 1 second for the time interval between the pulses. This optimal point led to a productivity of 1.29 mL/min and a purification factor of 4.96.Este trabalho teve como objetivo principal otimizar as condições para extração da bromelina do suco do abacaxi (Ananas comosus por micelas reversas. A purificação foi feita usando o processo de extração em batelada e contínuo, este último em uma micro-coluna de campânulas pulsantes. A solução micelar catiônica foi preparada com o surfactante BDBAC, i-octano como solvente e hexanol como co-solvente. Na extração em batelada encontrou-se um fator de purificação de 3 vezes, e seus melhores valores de concentração do agente surfactante, co-solvente e sal, de pH da re-extração e extração, foram respectivamente iguais a: 100 mM, 10% v/v, 1 M, 3,5 e 8. Para a operação contínua, as variáveis independentes ótimas foram: 0,67 para a razão entre as taxas de fluxos da fase leve e a total e 1 s para o intervalo de tempo entre pulsos das campânulas. Este ponto ótimo leva a uma produtividade de 1,29 mL/min e a um fator de purificação igual a 4,96.

  17. Landfill leachate treatment by batch supercritical water oxidation

    Directory of Open Access Journals (Sweden)

    Victor Fernando Marulanda Cardona

    2017-01-01

    Full Text Available El tratamiento de lixiviados por medio de diferentes procesos fisicoquímicos y biológicos ha sido ampliamente estudiado. Sin embargo, ningún proceso logra las eficiencias de destruc- ción requeridas en cuanto a materia orgánica y nitrógeno, razón por la cual el tratamiento se realiza por medio de tecnologías combinadas. La oxidación en agua supercrítica o SCWO, proceso que se lleva a cabo a temperaturas y presiones superiores a las del punto crítico del agua en presencia de una fuente de oxígeno, se ha aplicado exitosamente al tratamiento de distintos tipos de aguas residuales de forma eficiente. Por lo tanto, este trabajo presenta un estudio experimental de la oxidación en agua supercrítica de lixiviados de relleno sanitario en un reactor batch, en el rango de temperatura de 400-500°C, tiempos de reacción de 15 a 30 mi- nutos y excesos de oxígeno (OE de 100 % a 300 %. Se midieron las eficiencias de destrucción de carbono orgánico total (COT y nitrógeno total (NT, y se determinó el efecto combinado de los factores estudiados por medio del Análisis de Varianza (ANOVA. Las condiciones de operación óptimas para la destrucción de COT fueron 400°C, 30 min y 100 % OE, y 500°C, 30 min y 100 % OE para el NT. A diferencia de lo reportado en estudios similares, los resultados su- gieren que es posible llevar a cabo la destrucción simultánea del COT y el NT en los lixiviados por medio de SCWO a 400°C, 100 % OE y tiempos de residencia de más de 30 min sin usar un catalizador, ya sea en un proceso batch o continuo, siempre y cuando tanto el oxidante como el agua residual se mezclen y se calienten juntos a la temperatura de reacción.

  18. Fed-batch fermentation dealing with nitrogen limitation in microbial transglutaminase production by Streptoverticillium mobaraense

    NARCIS (Netherlands)

    Rinzema, A; Tramper, J; de Bruin, E; Bol, J

    In the later stages of a batch fermentation for microbial transglutaminase production by Streptoverticillium mobaraense the availability of a nitrogen source accessible to the microorganism becomes critical. Fed-batch fermentation is investigated with the aim of avoiding this substrate limitation.

  19. Fed-batch coculture of Lactobacillus kefiranofaciens with Saccharomyces cerevisiae for effective production of kefiran.

    Science.gov (United States)

    Tada, Shiori; Katakura, Yoshio; Ninomiya, Kazuaki; Shioya, Suteaki

    2007-06-01

    In a batch coculture of kefiran-producing lactic acid bacteria Lactobacillus kefiranofaciens and lactate-assimilating yeast Saccharomyces cerevisiae, lactate accumulation in the medium was observed, which inhibited kefiran production. To enhance kefiran productivity by preventing lactate accumulation, we conducted lactose-feeding batch operation with feedforward/feedback control during the coculture, so that the lactate production rate of L. kefiranofaciens was balanced with the lactate consumption rate of S. cerevisiae. The lactate concentration was maintained at less than 6 g l(-1) throughout the fed-batch coculture using a 5 l jar fermentor, although the concentration reached 33 g l(-1) in the batch coculture. Kefiran production was increased to 6.3 g in 102 h in the fed-batch coculture, whereas 4.5 g kefiran was produced in 97 h in the batch coculture. The kefiran yield on lactose basis was increased up to 0.033 g g(-1) in the fed-batch coculture, whereas that in the batch coculture was 0.027 g g(-1).

  20. Procedures for Separations within Batches of Values, 1. The Orderly Tool Kit and Some Heuristics

    Science.gov (United States)

    1989-03-01

    separations within batches of values, I. The orderly tool kit and some heuristics by Thu Hoang* and John W. Tukey** *Universite Rene Descartes ...separations with batches of values, . The orderly tool kit and heuristics Thu Hoang* and John W. Tukey** *Universite Rene Descartes Laboratoire de

  1. Limiting factors in Escherichia colifed-batch production of recombinant proteins

    DEFF Research Database (Denmark)

    Sanden, A.M.; Prytz, I.; Tubelekas, I.

    2003-01-01

    recombinant protein production, fed-batch, specific growth rate, feed profile, induction, mRNA, transcription, translation, acetic acid formation......recombinant protein production, fed-batch, specific growth rate, feed profile, induction, mRNA, transcription, translation, acetic acid formation...

  2. Batch fertility and larval parameters of the jaguar cichlid (Cichlasoma managuense spawned in the laboratory (ESP

    Directory of Open Access Journals (Sweden)

    Jorge Günther Nonell

    2016-03-01

    Full Text Available Batch fertility and larval parameters of 32 spawns of the jaguar guapote (Cichlasoma managuense in the laboratory were analyzed. Batch fertility was positively correlated with the female weight with spawns between about 3000 to 6000 larvae for females between 100 and 500 g wet weight. No significant correlation was found between larval parameters (fresh weight and % dry weight and female weight.

  3. Laboratory shake flask batch tests can predict field biodegradation of aniline in the Rhine

    DEFF Research Database (Denmark)

    Toräng, Lars; Reuschenbach, P.; Müller, B.

    2001-01-01

    .7 degreesC, respectively. This field rate estimate was compared with results from 38 laboratory shake flask batch tests with Rhine water which averaged 1.5 day(-1) at 15 degreesC and 2.0 day(-1) at 20 degreesC. These results indicate that laboratory shake flask batch tests with low concentrations of test...

  4. Simple approximations for the batch-arrival MX/G/1 queue

    NARCIS (Netherlands)

    van Ommeren, Jan C.W.

    1990-01-01

    In this paper we consider the MX/G/I queueing system with batch arrivals. We give simple approximations for the waiting-time probabilities of individual customers. These approximations are checked numerically and they are found to perform very well for a wide variety of batch-size and service-timed

  5. Monitoring and Characterization of Crystal Nucleation and Growth during Batch Crystallization

    NARCIS (Netherlands)

    Kadam, S.S.

    2012-01-01

    Batch crystallization is commonly used in pharmaceutical, agrochemical, specialty and fine chemicals industry. The advantages of batch crystallization lie in its ease of operation and the relatively simple equipment that can be used. On the other hand a major disadvantage associated with it is the

  6. Variance bias analysis for the Gelbard's batch method

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Jae Uk; Shim, Hyung Jin [Seoul National Univ., Seoul (Korea, Republic of)

    2014-05-15

    In this paper, variances and the bias will be derived analytically when the Gelbard's batch method is applied. And then, the real variance estimated from this bias will be compared with the real variance calculated from replicas. Variance and the bias were derived analytically when the batch method was applied. If the batch method was applied to calculate the sample variance, covariance terms between tallies which exist in the batch were eliminated from the bias. With the 2 by 2 fission matrix problem, we could calculate real variance regardless of whether or not the batch method was applied. However as batch size got larger, standard deviation of real variance was increased. When we perform a Monte Carlo estimation, we could get a sample variance as the statistical uncertainty of it. However, this value is smaller than the real variance of it because a sample variance is biased. To reduce this bias, Gelbard devised the method which is called the Gelbard's batch method. It has been certificated that a sample variance get closer to the real variance when the batch method is applied. In other words, the bias get reduced. This fact is well known to everyone in the MC field. However, so far, no one has given the analytical interpretation on it.

  7. 40 CFR 63.1326 - Batch process vents-recordkeeping provisions.

    Science.gov (United States)

    2010-07-01

    ....1325(e) for aggregate batch vent streams; (ii) For a boiler or process heater, a description of the location at which the vent stream is introduced into the boiler or process heater; (iii) For a boiler or... process vents or halogenated aggregate batch vent streams, the percent reduction of total hydrogen halides...

  8. 40 CFR 1065.245 - Sample flow meter for batch sampling.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Sample flow meter for batch sampling... Sample flow meter for batch sampling. (a) Application. Use a sample flow meter to determine sample flow... difference between a diluted exhaust sample flow meter and a dilution air meter to calculate raw exhaust flow...

  9. Selecting local constraint for alignment of batch process data with dynamic time warping

    DEFF Research Database (Denmark)

    Spooner, Max Peter; Kold, David; Kulahci, Murat

    2017-01-01

    ” may be interpreted as a progress signature of the batch which may be appended to the aligned data for further analysis. For the warping function to be a realistic reflection of the progress of a batch, it is necessary to impose some constraints on the dynamic time warping algorithm, to avoid...

  10. Research on AO/FO batch management technology in aircraft production

    Directory of Open Access Journals (Sweden)

    Yin Haijun

    2018-01-01

    Full Text Available Based on the analysis of the characteristics and significance of AO/FO in the process of aircraft production, this paper analyzes the format rules of AO/FO batch management from the perspective of technology realization, and details the AO/FO The change of the query and the change status tracking, introduces the AO/FO single-stand status display in the batch management, increases the structure definition of the attribute table in the batch management, and designs the relevant algorithm to store and calculate the batch information. Finally, based on the above theory support AO/FO batch management system successfully used in the production of a machine.

  11. Batched Tile Low-Rank GEMM on GPUs

    KAUST Repository

    Charara, Ali

    2018-02-01

    Dense General Matrix-Matrix (GEMM) multiplication is a core operation of the Basic Linear Algebra Subroutines (BLAS) library, and therefore, often resides at the bottom of the traditional software stack for most of the scientific applications. In fact, chip manufacturers give a special attention to the GEMM kernel implementation since this is exactly where most of the high-performance software libraries extract the hardware performance. With the emergence of big data applications involving large data-sparse, hierarchically low-rank matrices, the off-diagonal tiles can be compressed to reduce the algorithmic complexity and the memory footprint. The resulting tile low-rank (TLR) data format is composed of small data structures, which retains the most significant information for each tile. However, to operate on low-rank tiles, a new GEMM operation and its corresponding API have to be designed on GPUs so that it can exploit the data sparsity structure of the matrix while leveraging the underlying TLR compression format. The main idea consists in aggregating all operations onto a single kernel launch to compensate for their low arithmetic intensities and to mitigate the data transfer overhead on GPUs. The new TLR GEMM kernel outperforms the cuBLAS dense batched GEMM by more than an order of magnitude and creates new opportunities for TLR advance algorithms.

  12. Batch management based monitoring system: design, implement, and visualization

    International Nuclear Information System (INIS)

    Kan Bowen; Shi Jingyan

    2012-01-01

    Torque, an efficient PBS (Portable Batch System)-based open source Resource Management system, was originally developed by Ames research center of NASA, which was designed to satisfy the computing requirements of heterogeneous network. With the development of distributed computing, Torque has been widely used in high performance computing cluster. However, because of the lack of a well designed monitoring system, it is difficult to monitor, record, and control, leading to low stability, reliability and manageability. To overcome those problems, this paper designs and implements an adaptive lightweight monitoring system for torque from five aspects. 1) A lightweight circulating filtration logging system is developed to obtain the real-time running status of torque; 2) One uniform interface was provided for administrators to define monitoring commands, which can query management resources of torque; 3) Storage strategy is designed to make monitoring information persistent; 4) One uniform interface is provided for users to customized alarms, which can submit exceptions and errors to users via emails and SMS in real time; 5) HTML5 technology is applied in the customizable visualization of the jobs' status in torque in real time. (authors)

  13. Degradation of formaldehyde in anaerobic sequencing batch biofilm reactor (ASBBR)

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, N.S. [Laboratorio de Processos Biologicos (LPB), Departamento de Hidraulica e Saneamento, Escola de Engenharia de Sao Carlos (EESC), Universidade de Sao Paulo - USP, Engenharia Ambiental, Bloco 4-F, Av. Joao Dagnone, 1100 Santa Angelina, 13.563-120 Sao Carlos, SP (Brazil); Zaiat, M. [Laboratorio de Processos Biologicos (LPB), Departamento de Hidraulica e Saneamento, Escola de Engenharia de Sao Carlos (EESC), Universidade de Sao Paulo - USP, Engenharia Ambiental, Bloco 4-F, Av. Joao Dagnone, 1100 Santa Angelina, 13.563-120 Sao Carlos, SP (Brazil)], E-mail: zaiat@sc.usp.br

    2009-04-30

    The present study evaluated the degradation of formaldehyde in a bench-scale anaerobic sequencing batch reactor, which contained biomass immobilized in polyurethane foam matrices. The reactor was operated for 212 days at 35 deg. C with 8 h sequential cycles, under different affluent formaldehyde concentrations ranging from 31.6 to 1104.4 mg/L (formaldehyde loading rates from 0.08 to 2.78 kg/m{sup 3} day). The results indicate excellent reactor stability and over 99% efficiency in formaldehyde removal, with average effluent formaldehyde concentration of 3.6 {+-} 1.7 mg/L. Formaldehyde degradation rates increased from 204.9 to 698.3 mg/L h as the initial concentration of formaldehyde was increased from around 100 to around 1100 mg/L. However, accumulation of organic matter was observed in the effluent (chemical oxygen demand (COD) values above 500 mg/L) due to the presence of non-degraded organic acids, especially acetic and propionic acids. This observation poses an important question regarding the anaerobic route of formaldehyde degradation, which might differ substantially from that reported in the literature. The anaerobic degradation pathway can be associated with the formation of long-chain oligomers from formaldehyde. Such long- or short-chain polymers are probably the precursors of organic acid formation by means of acidogenic anaerobic microorganisms.

  14. Treatment of winery wastewater by an anaerobic sequencing batch reactor.

    Science.gov (United States)

    Ruíz, C; Torrijos, M; Sousbie, P; Lebrato Martínez, J; Moletta, R; Delgenès, J P

    2002-01-01

    Treatment of winery wastewater was investigated using an anaerobic sequencing batch reactor (ASBR). Biogas production rate was monitored and permitted the automation of the bioreactor by a simple control system. The reactor was operated at an organic loading rate (ORL) around 8.6 gCOD/L.d with soluble chemical oxygen demand (COD) removal efficiency greater than 98%, hydraulic retention time (HRT) of 2.2 d and a specific organic loading rate (SOLR) of 0.96 gCOD/gVSS.d. The kinetics of COD and VFA removal were investigated for winery wastewater and for simple compounds such as ethanol, which is a major component of winery effluent, and acetate, which is the main volatile fatty acid (VFA) produced. The comparison of the profiles obtained with the 3 substrates shows that, overall, the acidification of the organic matter and the methanisation of the VFA follow zero order reactions, in the operating conditions of our study. The effect on the gas production rate resulted in two level periods separated by a sharp break when the acidification stage was finished and only the breaking down of the VFA continued.

  15. Operational strategies for nitrogen removal in granular sequencing batch reactor

    International Nuclear Information System (INIS)

    Chen, Fang-yuan; Liu, Yong-Qiang; Tay, Joo-Hwa; Ning, Ping

    2011-01-01

    This study investigated the effects of different operational strategies for nitrogen removal by aerobic granules with mean granule sizes of 1.5 mm and 0.7 mm in a sequencing batch reactor (SBR). With an alternating anoxic/oxic (AO) operation mode without control of dissolve oxygen (DO), the granular sludge with different size achieved the total inorganic nitrogen (TIN) removal efficiencies of 67.8-71.5%. While under the AO condition with DO controlled at 2 mg/l at the oxic phase, the TIN removal efficiency was improved up to 75.0-80.4%. A novel operational strategy of alternating anoxic/oxic combined with the step-feeding mode was developed for nitrogen removal by aerobic granules. It was found that nitrogen removal efficiencies could be further improved to 93.0-95.9% with the novel strategy. Obviously, the alternating anoxic/oxic strategy combined with step-feeding is the optimal way for TIN removal by granular sludge, which is independent of granule size.

  16. Arsenic Removal and Its Chemistry in Batch Electrocoagulation Studies.

    Science.gov (United States)

    Sharma, Anshul; Adapureddy, Sri Malini; Goel, Sudha

    2014-04-01

    The aim of this study was to evaluate the impact of different oxidizing agents like light, aeration (by mixing) and electrocoagulation (EC) on the oxidation of As (III) and its subsequent removal in an EC batch reactor. Arsenic solutions prepared using distilled water and groundwater were evaluated. Optimum pH and the effect of varying initial pH on As removal efficiency were also evaluated. MaximumAs (III) removal efficiency with EC, light and aeration was 97% from distilled water and 71% from groundwater. Other results show that EC alone resulted in 90% As removal efficiency in the absence of light and mixing from distilled water and 53.6% from groundwater. Removal with light and mixing but without EC resulted in only 26% As removal from distilled water and 29% from groundwater proving that electro-oxidation and coagulation were more effective in removing arsenic compared to the other oxidizing agents examined. Initial pH was varied from 5 to 10 in distilled water and from 3 to 12 in groundwater for evaluating arsenic removal efficiency by EC. The optimum initial pH for arsenic removal was 7 for distilled water and groundwater. For all initial pHs tested between 5 and 10 in distilled water, the final pH ranged between 7 and 8 indicating that the EC process tends towards near neutral pH under the conditions examined in this study.

  17. ColorTree: a batch customization tool for phylogenic trees.

    Science.gov (United States)

    Chen, Wei-Hua; Lercher, Martin J

    2009-07-31

    Genome sequencing projects and comparative genomics studies typically aim to trace the evolutionary history of large gene sets, often requiring human inspection of hundreds of phylogenetic trees. If trees are checked for compatibility with an explicit null hypothesis (e.g., the monophyly of certain groups), this daunting task is greatly facilitated by an appropriate coloring scheme. In this note, we introduce ColorTree, a simple yet powerful batch customization tool for phylogenic trees. Based on pattern matching rules, ColorTree applies a set of customizations to an input tree file, e.g., coloring labels or branches. The customized trees are saved to an output file, which can then be viewed and further edited by Dendroscope (a freely available tree viewer). ColorTree runs on any Perl installation as a stand-alone command line tool, and its application can thus be easily automated. This way, hundreds of phylogenic trees can be customized for easy visual inspection in a matter of minutes. ColorTree allows efficient and flexible visual customization of large tree sets through the application of a user-supplied configuration file to multiple tree files.

  18. Virtual Sensors for Biodiesel Production in a Batch Reactor

    Directory of Open Access Journals (Sweden)

    Betty Y. López-Zapata

    2017-03-01

    Full Text Available Fossil fuel combustion produces around 98% of coal emissions. Therefore, liquid and gaseous biofuels have become more attractive due to their environmental benefits. The biodiesel production process requires measurements that help to control and supervise the variables involved in the process. The measurements provide valuable information about the operation conditions and give estimations about the critical variables of the process. The information from measurements is essential for monitoring the state of a process and verifying if it has an optimal performance. The objective of this study was the conception of a virtual sensor based on the Extended Kalman Filter (EKF and the model of a batch biodiesel reactor for estimating concentrations of triglycerides (TG, diglycerides (DG, monoglycerides (MG, methyl ester (E, alcohol (A, and glycerol (GL in real-time through measurement of the temperature and pH. Estimation of the TG, DG, MG, E, A, and Gl through this method eliminates the need for additional sensors and allows the use of different types of control. For the performance analysis of the virtual sensor, the data obtained from the EKF are compared with experimental data reported in the literature, with the mean square error of the estimate then being calculated. In addition, the results of this approach can be implemented in a real system, since it only uses measurements available in a reactor such as temperature and pH.

  19. Methods for batch fabrication of cold cathode vacuum switch tubes

    Science.gov (United States)

    Walker, Charles A [Albuquerque, NM; Trowbridge, Frank R [Albuquerque, NM

    2011-05-10

    Methods are disclosed for batch fabrication of vacuum switch tubes that reduce manufacturing costs and improve tube to tube uniformity. The disclosed methods comprise creating a stacked assembly of layers containing a plurality of adjacently spaced switch tube sub-assemblies aligned and registered through common layers. The layers include trigger electrode layer, cathode layer including a metallic support/contact with graphite cathode inserts, trigger probe sub-assembly layer, ceramic (e.g. tube body) insulator layer, and metallic anode sub-assembly layer. Braze alloy layers are incorporated into the stacked assembly of layers, and can include active metal braze alloys or direct braze alloys, to eliminate costs associated with traditional metallization of the ceramic insulator layers. The entire stacked assembly is then heated to braze/join/bond the stack-up into a cohesive body, after which individual switch tubes are singulated by methods such as sawing. The inventive methods provide for simultaneously fabricating a plurality of devices as opposed to traditional methods that rely on skilled craftsman to essentially hand build individual devices.

  20. Degradation of formaldehyde in anaerobic sequencing batch biofilm reactor (ASBBR)

    International Nuclear Information System (INIS)

    Pereira, N.S.; Zaiat, M.

    2009-01-01

    The present study evaluated the degradation of formaldehyde in a bench-scale anaerobic sequencing batch reactor, which contained biomass immobilized in polyurethane foam matrices. The reactor was operated for 212 days at 35 deg. C with 8 h sequential cycles, under different affluent formaldehyde concentrations ranging from 31.6 to 1104.4 mg/L (formaldehyde loading rates from 0.08 to 2.78 kg/m 3 day). The results indicate excellent reactor stability and over 99% efficiency in formaldehyde removal, with average effluent formaldehyde concentration of 3.6 ± 1.7 mg/L. Formaldehyde degradation rates increased from 204.9 to 698.3 mg/L h as the initial concentration of formaldehyde was increased from around 100 to around 1100 mg/L. However, accumulation of organic matter was observed in the effluent (chemical oxygen demand (COD) values above 500 mg/L) due to the presence of non-degraded organic acids, especially acetic and propionic acids. This observation poses an important question regarding the anaerobic route of formaldehyde degradation, which might differ substantially from that reported in the literature. The anaerobic degradation pathway can be associated with the formation of long-chain oligomers from formaldehyde. Such long- or short-chain polymers are probably the precursors of organic acid formation by means of acidogenic anaerobic microorganisms

  1. Kinetics of steel slag leaching: Batch tests and modeling

    International Nuclear Information System (INIS)

    De Windt, Laurent; Chaurand, Perrine; Rose, Jerome

    2011-01-01

    Reusing steel slag as an aggregate for road construction requires to characterize the leaching kinetics and metal releases. In this study, basic oxygen furnace (BOF) steel slag were subjected to batch leaching tests at liquid to solid ratios (L/S) of 10 and 100 over 30 days; the leachate chemistry being regularly sampled in time. A geochemical model of the steel slag is developed and validated from experimental data, particularly the evolution with leaching of mineralogical composition of the slag and trace element speciation. Kinetics is necessary for modeling the primary phase leaching, whereas a simple thermodynamic equilibrium approach can be used for secondary phase precipitation. The proposed model simulates the kinetically-controlled dissolution (hydrolysis) of primary phases, the precipitation of secondary phases (C-S-H, hydroxide and spinel), the pH and redox conditions, and the progressive release of major elements as well as the metals Cr and V. Modeling indicates that the dilution effect of the L/S ratio is often coupled to solubility-controlled processes, which are sensitive to both the pH and the redox potential. A sensitivity analysis of kinetic uncertainties on the modeling of element releases is performed.

  2. molecular weight control of a batch suspension polymerization reactor

    International Nuclear Information System (INIS)

    Shahrokhi, M.; Fanaei, M. A.

    2002-01-01

    This paper concerns molecular weight control of a batch polymerization reactor where suspension polymerization of methyl methylacrylate (MMA) takes place. For this purpose, a cascade control structure with two control loops has been selected. The slave loop is used for temperature control using on-line temperature measurements, and the master loop controls the average molecular weights based on its estimated values. Two different control algorithms namely proportional-integral (PI) controller and globally linearizing controller (GLC) have been used for temperature control. An estimator, which has the structure of an extended Kalman filter(EKF), is used for estimating monomer conversion and average molecular weights of polymer using reactor temperature measurements. The performance of proposed control algorithm is evaluated through simulation and experimental studies. The results indicate that a constant average molecular weight cannot be achieved in case of strong gel effect. However, the polydispersity of product will be lower in comparison to isothermal operation. It is also shown that in case of mo dek mismatch, the performance of cascade control is superior compared to the case where only reactor temperature is controlled based on desired temperature trajectory obtained through cascade strategy

  3. Environmental Hazard Assessment of Jarosite Waste Using Batch Leaching Tests

    Directory of Open Access Journals (Sweden)

    M. Kerolli – Mustafa

    2018-01-01

    Full Text Available Jarosite waste samples from Trepça Zinc Industry in Kosovo were subjected to two batch leaching tests as an attempt to characterize the leaching behavior and mobility of minor and major elements of jarosite waste. To achieve this, deionized water and synthetic acidic rain leaching tests were employed. A two-step acidic treatment in microwave digestion system were used to dissolve jarosite waste samples, followed by determination of Al, Ag, As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, P, Pb, S, Si, Sr, and Zn by inductively coupled plasma optical emission spectrometry (ICP-OES. The validation of the procedure was performed by the analysis of two geochemical reference materials, S JR-3 and S Jsy-1. Two toxicity leaching tests revealed a high metal releasing of Cd, Cu, Ni, Mn, Pb, Zn, and As, and the metal release risk for these elements is still very high due the low pH and acid rain. The statistical analysis showed useful data information on the relationship between elements in jarosite samples in two different extraction conditions (deionized water and synthetic acid rain.

  4. Parallel Machine Scheduling with Batch Delivery to Two Customers

    Directory of Open Access Journals (Sweden)

    Xueling Zhong

    2015-01-01

    Full Text Available In some make-to-order supply chains, the manufacturer needs to process and deliver products for customers at different locations. To coordinate production and distribution operations at the detailed scheduling level, we study a parallel machine scheduling model with batch delivery to two customers by vehicle routing method. In this model, the supply chain consists of a processing facility with m parallel machines and two customers. A set of jobs containing n1 jobs from customer 1 and n2 jobs from customer 2 are first processed in the processing facility and then delivered to the customers directly without intermediate inventory. The problem is to find a joint schedule of production and distribution such that the tradeoff between maximum arrival time of the jobs and total distribution cost is minimized. The distribution cost of a delivery shipment consists of a fixed charge and a variable cost proportional to the total distance of the route taken by the shipment. We provide polynomial time heuristics with worst-case performance analysis for the problem. If m=2 and (n1-b(n2-b<0, we propose a heuristic with worst-case ratio bound of 3/2, where b is the capacity of the delivery shipment. Otherwise, the worst-case ratio bound of the heuristic we propose is 2-2/(m+1.

  5. Repeatability & Workability Evaluation of SIGMOD 2009

    KAUST Repository

    Manegold, Stefan

    2010-12-15

    SIGMOD 2008 was the first database conference that offered to test submitters\\' programs against their data to verify the repeatability of the experiments published [1]. Given the positive feedback concerning the SIGMOD 2008 repeatability initiative, SIGMOD 2009 modified and expanded the initiative with a workability assessment.

  6. simple sequence repeats (EST-SSR)

    African Journals Online (AJOL)

    Yomi

    2012-01-19

    Jan 19, 2012 ... 212 primer pairs selected, based on repeat patterns of n≥8 for di-, tri-, tetra- and penta-nucleotide repeat ... Cluster analysis revealed a high genetic similarity among the sugarcane (Saccharum spp.) breeding lines which could reduce the genetic gain in ..... The multiple allele characteristic of SSR com-.

  7. Repeatability & Workability Evaluation of SIGMOD 2009

    KAUST Repository

    Manegold, Stefan; Manolescu, Ioana; Afanasiev, Loredana; Feng, Jieling; Gou, G.; Hadjieleftheriou, Marios; Harizopoulos, Stavros; Kalnis, Panos; Karanasos, Konstantinos; Laurent, Dominique; Lupu, M.; Onose, N.; Ré , C.; Sans, Virginie; Senellart, Pierre; Wu, T.; Shasha, Dennis E.

    2010-01-01

    SIGMOD 2008 was the first database conference that offered to test submitters' programs against their data to verify the repeatability of the experiments published [1]. Given the positive feedback concerning the SIGMOD 2008 repeatability initiative, SIGMOD 2009 modified and expanded the initiative with a workability assessment.

  8. UK 2009-2010 repeat station report

    Directory of Open Access Journals (Sweden)

    Thomas J.G. Shanahan

    2013-03-01

    Full Text Available The British Geological Survey is responsible for conducting the UK geomagnetic repeat station programme. Measurements made at the UK repeat station sites are used in conjunction with the three UK magnetic observatories: Hartland, Eskdalemuir and Lerwick, to produce a regional model of the local field each year. The UK network of repeat stations comprises 41 stations which are occupied at approximately 3-4 year intervals. Practices for conducting repeat station measurements continue to evolve as advances are made in survey instrumentation and as the usage of the data continues to change. Here, a summary of the 2009 and 2010 UK repeat station surveys is presented, highlighting the measurement process and techniques, density of network, reduction process and recent results.

  9. Lactic Acid Bacterial Starter Culture with Antioxidant and γ-Aminobutyric Acid Biosynthetic Activities Isolated from Flatfish-Sikhae Fermentation.

    Science.gov (United States)

    Won, Yeong Geol; Yu, Hyun-Hee; Chang, Young-Hyo; Hwang, Han-Joon

    2015-12-01

    The aim of this study is to select a lactic acid bacterial strain as a starter culture for flatfish-Sikhae fermentation and to evaluate its suitability for application in a food system. Four strains of lactic acid bacteria isolated from commercial flatfish-Sikhae were identified and selected as starter culture candidates through investigation of growth rates, salt tolerance, food safety, and functional properties such as antioxidative and antimicrobial activities. The fermentation properties of the starter candidates were also examined in food systems prepared with these strains (candidate batch) in comparison with a spontaneous fermentation process without starter culture (control batch) at 15°C. The results showed that the candidate YG331 batch had better fermentation properties such as viable cell count, pH, and acidity than the other experimental batches, including the control batch. The results are expressed according to selection criteria based on a preliminary sensory evaluation and physiochemical investigation. Also, only a small amount of histamine was detected with the candidate YG331 batch. The radical scavenging activity of the candidate batches was better compared with the control batch, and especially candidate YG331 batch showed the best radical scavenging activity. Also, we isolated another starter candidate (identified as Lactobacillus brevis PM03) with γ-aminobutyric acid (GABA)-producing activity from commercial flatfish-Sikhae products. The sensory scores of the candidate YG331 batch were better than those of the other experimental batches in terms of flavor, color, and overall acceptance. In this study, we established selection criteria for the lactic acid bacterial starter for the flatfish-Sikhae production and finally selected candidate YG331 as the most suitable starter.

  10. Thermo- and mesophilic aerobic batch biodegradation of high-strength distillery wastewater (potato stillage)--utilisation of main carbon sources.

    Science.gov (United States)

    Krzywonos, Małgorzata; Cibis, Edmund; Lasik, Małgorzata; Nowak, Jacek; Miśkiewicz, Tadeusz

    2009-05-01

    The aim of the study was to ascertain the extent to which temperature influences the utilisation of main carbon sources (reducing substances determined before and after hydrolysis, glycerol and organic acids) by a mixed culture of thermo- and mesophilic bacteria of the genus Bacillus in the course of aerobic batch biodegradation of potato stillage, a high-strength distillery effluent (COD=51.88 g O(2)/l). The experiments were performed at 20, 30, 35, 40, 45, 50, 55, 60 and 63 degrees C, at pH 7, in a 5l working volume stirred-tank bioreactor (Biostat B, B. Braun Biotech International) with a stirrer speed of 550 rpm and aeration at 1.6 vvm. Particular consideration was given to the following issues: (1) the sequence in which the main carbon sources in the stillage were assimilated and (2) the extent of their assimilation achieved under these conditions.

  11. Tc-99 Adsorption on Selected Activated Carbons - Batch Testing Results

    Energy Technology Data Exchange (ETDEWEB)

    Mattigod, Shas V.; Wellman, Dawn M.; Golovich, Elizabeth C.; Cordova, Elsa A.; Smith, Ronald M.

    2010-12-01

    CH2M HILL Plateau Remediation Company (CHPRC) is currently developing a 200-West Area groundwater pump-and-treat system as the remedial action selected under the Comprehensive Environmental Response, Compensation, and Liability Act Record of Decision for Operable Unit (OU) 200-ZP-1. This report documents the results of treatability tests Pacific Northwest National Laboratory researchers conducted to quantify the ability of selected activated carbon products (or carbons) to adsorb technetium-99 (Tc-99) from 200-West Area groundwater. The Tc-99 adsorption performance of seven activated carbons (J177601 Calgon Fitrasorb 400, J177606 Siemens AC1230AWC, J177609 Carbon Resources CR-1240-AW, J177611 General Carbon GC20X50, J177612 Norit GAC830, J177613 Norit GAC830, and J177617 Nucon LW1230) were evaluated using water from well 299-W19-36. Four of the best performing carbons (J177606 Siemens AC1230AWC, J177609 Carbon Resources CR-1240-AW, J177611 General Carbon GC20X50, and J177613 Norit GAC830) were selected for batch isotherm testing. The batch isotherm tests on four of the selected carbons indicated that under lower nitrate concentration conditions (382 mg/L), Kd values ranged from 6,000 to 20,000 mL/g. In comparison. Under higher nitrate (750 mg/L) conditions, there was a measureable decrease in Tc-99 adsorption with Kd values ranging from 3,000 to 7,000 mL/g. The adsorption data fit both the Langmuir and the Freundlich equations. Supplemental tests were conducted using the two carbons that demonstrated the highest adsorption capacity to resolve the issue of the best fit isotherm. These tests indicated that Langmuir isotherms provided the best fit for Tc-99 adsorption under low nitrate concentration conditions. At the design basis concentration of Tc 0.865 µg/L(14,700 pCi/L), the predicted Kd values from using Langmuir isotherm constants were 5,980 mL/g and 6,870 mL/g for for the two carbons. These Kd values did not meet the target Kd value of 9,000 mL/g. Tests

  12. Biological reduction of chlorinated solvents: Batch-scale geochemical modeling

    Science.gov (United States)

    Kouznetsova, Irina; Mao, Xiaomin; Robinson, Clare; Barry, D. A.; Gerhard, Jason I.; McCarty, Perry L.

    2010-09-01

    Simulation of biodegradation of chlorinated solvents in dense non-aqueous phase liquid (DNAPL) source zones requires a model that accounts for the complexity of processes involved and that is consistent with available laboratory studies. This paper describes such a comprehensive modeling framework that includes microbially mediated degradation processes, microbial population growth and decay, geochemical reactions, as well as interphase mass transfer processes such as DNAPL dissolution, gas formation and mineral precipitation/dissolution. All these processes can be in equilibrium or kinetically controlled. A batch modeling example was presented where the degradation of trichloroethene (TCE) and its byproducts and concomitant reactions (e.g., electron donor fermentation, sulfate reduction, pH buffering by calcite dissolution) were simulated. Local and global sensitivity analysis techniques were applied to delineate the dominant model parameters and processes. Sensitivity analysis indicated that accurate values for parameters related to dichloroethene (DCE) and vinyl chloride (VC) degradation (i.e., DCE and VC maximum utilization rates, yield due to DCE utilization, decay rate for DCE/VC dechlorinators) are important for prediction of the overall dechlorination time. These parameters influence the maximum growth rate of the DCE and VC dechlorinating microorganisms and, thus, the time required for a small initial population to reach a sufficient concentration to significantly affect the overall rate of dechlorination. Self-inhibition of chlorinated ethenes at high concentrations and natural buffering provided by the sediment were also shown to significantly influence the dechlorination time. Furthermore, the analysis indicated that the rates of the competing, nonchlorinated electron-accepting processes relative to the dechlorination kinetics also affect the overall dechlorination time. Results demonstrated that the model developed is a flexible research tool that is

  13. Batch crystallization of rifapentine for inhalable tuberculosis medication

    Science.gov (United States)

    Wijanarko, Anondho; Meivita, Maria Prisca; Hermansyah, Heri; Sahlan, Muhamad; Lakerveld, Richard

    2018-02-01

    In the midst of Tuberculosis (TB) pandemic, a research about new tuberculosis drug that results in more rapid resolution of tubercular infection is important. It will play a crucial role in accelerating the reductions in tuberculosis incidence that is occurring worldwide. The effectiveness of rifapentine has been assessed and it has been proven to be the most effective antibiotics for TB. A frequent administration and dose of rifapentine resulted in more rapid resolution of tubercular infection. However, based on former research, high exposure levels for treatment shortening may be unachievable with oral administration and might instead be achieved by direct aerosol delivery of rifapentine to the pulmonary site of infection. Therefore, with the growing interest in the effectiveness of rifapentine in frequent administration and dose, this research integrates an inhalable form of crystalline rifapentine prepared using a batch process. Moreover, this research investigates the effect of seed loading, supersaturation ratio, and residence time on the characterization of crystalline rifapentine in order to form a crystalline rifapentine in an inhalable size. The research was carried out by using anti-solvent crystallization method with acetone as a solvent and distilled water as an anti-solvent. Based on the assessment of various operating variables, it can be concluded that the optimum result was obtained at the unseeded experiment with supersaturation ratio = 1.26. Unseeded experiments are preferred because the ideal size for therapeutic aerosol was achieved in unseeded experiments. At the request of all authors the above article is being retracted due to publication without knowledge or consent from one of the principal investigators of the research listed on the article, Dr. Richard Lakerveld. This article is retracted from the scientific record with effect from 18 May 2018.

  14. Hierarchical Bayesian models to assess between- and within-batch variability of pathogen contamination in food.

    Science.gov (United States)

    Commeau, Natalie; Cornu, Marie; Albert, Isabelle; Denis, Jean-Baptiste; Parent, Eric

    2012-03-01

    Assessing within-batch and between-batch variability is of major interest for risk assessors and risk managers in the context of microbiological contamination of food. For example, the ratio between the within-batch variability and the between-batch variability has a large impact on the results of a sampling plan. Here, we designed hierarchical Bayesian models to represent such variability. Compatible priors were built mathematically to obtain sound model comparisons. A numeric criterion is proposed to assess the contamination structure comparing the ability of the models to replicate grouped data at the batch level using a posterior predictive loss approach. Models were applied to two case studies: contamination by Listeria monocytogenes of pork breast used to produce diced bacon and contamination by the same microorganism on cold smoked salmon at the end of the process. In the first case study, a contamination structure clearly exists and is located at the batch level, that is, between batches variability is relatively strong, whereas in the second a structure also exists but is less marked. © 2012 Society for Risk Analysis.

  15. Sorption of fluoride by quartz sand: batch tests

    Directory of Open Access Journals (Sweden)

    Eduardo Usunoff

    2009-06-01

    Full Text Available Despite the many efforts of scientists, in particular those from the field of soil science, the fate and distribution of fluorine (F species in soils and aquifers remain relatively unraveled. As for groundwater systems, such a shortcoming makes difficult the finding and development of safe water supplies. Likewise, the use of transport models does not render acceptable results because of the many uncertainties related to the behavior of F in aqueous media. This paper presents the results of four batch test in which solutions of different pH and [F-] (concentration of fluoride were in contact during 48 hours with clean quartz sand grains. The resulting data were fitted by linear versions of the Freundlich, the Langmuir, and the Langmuir-Freundlich models. The [F-] was varied between 0,5 and 10 mg L-1, except in one batch where a large initial concentration of F was used (45 mg L-1, and the range of pH used was 2,95 to 5,02. From a sieve analysis, the quartz grains had a medium size (d50 of 0,25 mm, and a uniformity coefficient (d40/d90 of 1,65. According to the fits and some dedicated goodness of fit indices, the Langmuir-Freundlich approach gave the best results for the batch test at the lowest pH, whereas the three remaining tests data were fitted by the Freundlich equation. It has to be mentioned that the pH of the equilibrium solutions were higher than the pH of the initial solutions, which was interpreted as an exchange process of OH- by F- on the quartz sand surface. However, such an exchange does not stand out as the exclusive mechanism promoting the F- disappearance from solution. It is deemed that the obtained results can be used as initial estimates of parameters in models used for calibrating the transport of F- in aquifers.A pesar de los muchos esfuerzos de los científicos, en particular de aquellos dedicados a las ciencias del suelo, el destino y la distribución de las especies de F (flúor en suelos y acuíferos continúan siendo

  16. The relationship of social support concept and repeat mammography among Iranian women.

    Science.gov (United States)

    Farhadifar, Fariba; Taymoori, Parvaneh; Bahrami, Mitra; Zarea, Shamsy

    2015-10-24

    Breast cancer ranks as the first most common cancer among the Iranian women. The regular repeat of mammography with 1-2 year intervals leads to the increased efficiency of early detection of breast cancer. The present study examined the predictors of repeat mammography. It was hypothesized that higher social support is connected with mammography repeat. A cross-sectional study was carried out among 400 women 50 years and older in Sanandaj, Iran. Data was collected by the questionnaire including information on socio demographical variables and measuring social support level. Data was analyzed by SPSS16 software. Multiple logistic regression was used to determine the predictive power of demographic variables and dimensions of social support for repeat mammography. Women aged 50-55 years had three times odds of repeat mammography compared to women aged 56-60 years) OR, 3.02). Married women had greater odds of repeat mammography compared to single women (P women with higher social support was 0.93 times greater than the women with lower social support (OR, 0.93; 95 % CI, 0.91-0.95; P women are less likely repeat mammography than other Asian women. Identifying the associations between perceived social support and repeat mammography may offer detailed information to allow for future study and guide the development of interventions not only for Iranian women but also for similar cultural that received pay too little attention to date in the breast cancer literature.

  17. Development of analog watch with minute repeater

    Science.gov (United States)

    Okigami, Tomio; Aoyama, Shigeru; Osa, Takashi; Igarashi, Kiyotaka; Ikegami, Tomomi

    A complementary metal oxide semiconductor with large scale integration was developed for an electronic minute repeater. It is equipped with the synthetic struck sound circuit to generate natural struck sound necessary for the minute repeater. This circuit consists of an envelope curve drawing circuit, frequency mixer, polyphonic mixer, and booster circuit made by using analog circuit technology. This large scale integration is a single chip microcomputer with motor drivers and input ports in addition to the synthetic struck sound circuit, and it is possible to make an electronic system of minute repeater at a very low cost in comparison with the conventional type.

  18. A study on radiographic repeat rate data of several hospitals in Jeddah

    Energy Technology Data Exchange (ETDEWEB)

    Al-Malki, M.A.; Abulfaraj, W.H.; Bhuiyan, S.I.; Kinsara, A.A

    2003-07-01

    Radiographic repeat rate data in diagnostic radiology in King Fahad Hospital (KFH), King Abdulaziz Hospital (KAH), and Maternity and Children Hospital (MCH) in Jeddah, Saudi Arabia, have been studied. The study provided valuable information to suggest preventive measures to reduce repeats. The variables included in the study are exposure techniques, examination types, total number of films used, number of films repeated, the film sizes, gender, the age groups of the patients, and reason for repetition. The total number of examinations in all three hospitals is 6001 using 8887 films on 5412 patients. The average repeat rate was 7.93%, where the individual hospital repeat rates were 9.57% in the MCH, 7.84% in KAH and 7.44% in KFH. The repeat rate for children and infants was found to be undesirable. The quality assurance (QA) programme can effectively reduce the unnecessary exposure and can identify the cause of the exposure. The overexposure, underexposure and position fault were the foremost contributors for repeats and constitute 32.91%, 28.94% and 22.98% of the total respectively. The QA study identified that human error and equipment malfunction are the major contributors to these causes of repeats. The highest repetition rate was for pelvis, 13.64%, followed by skull, 11.59%, and abdomen, 10.41%. It is estimated that the total area of wasted film in all three hospitals is 74.3 m{sup 2}. As per the average repeat rate, the cost of repeat films in the entire kingdom per year has been projected to be about US$1.82 million (SR 6.83 million) in the government hospitals only. Based on the findings of this study a set of recommendations have been prescribed for the radiology department to reduce the repeat rate and to improve the safety culture. (author)

  19. A study on radiographic repeat rate data of several hospitals in Jeddah

    International Nuclear Information System (INIS)

    Al-Malki, M.A.; Abulfaraj, W.H.; Bhuiyan, S.I.; Kinsara, A.A.

    2003-01-01

    Radiographic repeat rate data in diagnostic radiology in King Fahad Hospital (KFH), King Abdulaziz Hospital (KAH), and Maternity and Children Hospital (MCH) in Jeddah, Saudi Arabia, have been studied. The study provided valuable information to suggest preventive measures to reduce repeats. The variables included in the study are exposure techniques, examination types, total number of films used, number of films repeated, the film sizes, gender, the age groups of the patients, and reason for repetition. The total number of examinations in all three hospitals is 6001 using 8887 films on 5412 patients. The average repeat rate was 7.93%, where the individual hospital repeat rates were 9.57% in the MCH, 7.84% in KAH and 7.44% in KFH. The repeat rate for children and infants was found to be undesirable. The quality assurance (QA) programme can effectively reduce the unnecessary exposure and can identify the cause of the exposure. The overexposure, underexposure and position fault were the foremost contributors for repeats and constitute 32.91%, 28.94% and 22.98% of the total respectively. The QA study identified that human error and equipment malfunction are the major contributors to these causes of repeats. The highest repetition rate was for pelvis, 13.64%, followed by skull, 11.59%, and abdomen, 10.41%. It is estimated that the total area of wasted film in all three hospitals is 74.3 m 2 . As per the average repeat rate, the cost of repeat films in the entire kingdom per year has been projected to be about US$1.82 million (SR 6.83 million) in the government hospitals only. Based on the findings of this study a set of recommendations have been prescribed for the radiology department to reduce the repeat rate and to improve the safety culture. (author)

  20. Decolorization of reactive dyes under batch anaerobic condition by ...

    African Journals Online (AJOL)

    However, decolorization was lower for the dye of RB 49 than other two dyes in all concentrations despite 72 h incubation period by mixed anaerobic culture. All of the three dyes correlated with 1st order reaction kinetic with respect to decolorization kinetics. The results of the study demonstrated that high decolorization was ...