Comparative fermentation behaviour and chemical characteristics of Saccharomyces and Zymomonas fermented culled apple juice.

PubMed

Sandhu, D K; Joshi, V K

1994-12-01

Ethanol production from culled apple juice showed that fermentability of the juice could be enhanced by addition of DAHP or ammonium sulphate in Saccharomyces and DAHP in Zymomonas fermentation. Addition of trace elements inhibited both the fermentations and ethanol, consequently. With respect to by-products of fermentation, no clear advantage of Zymomnas fermentation of culled apple juice could be observed. Differences in physico-chemical characteristics of the fermented apple juice were also noted. Saccharomyces cerevisiae proved to be better than Zymomonas in most of the parameters and is preferrable from handling and spoilage point of view.

Ethanol production using xylitol synthesis mutant of xylose-utilizing zymomonas

DOEpatents

Viitanen, Paul V.; McCutchen, Carol M.; Emptage, Mark; Caimi, Perry G.; Zhang, Min; Chou, Yat-Chen

2010-06-22

Production of ethanol using a strain of xylose-utilizing Zymomonas with a genetic modification of the glucose-fructose oxidoreductase gene was found to be improved due to greatly reduced production of xylitol, a detrimental by-product of xylose metabolism synthesized during fermentation.

Xylose utilizing Zymomonas mobilis with improved ethanol production in biomass hydrolysate medium

DOEpatents

Caimi, Perry G; Hitz, William D; Viitanen, Paul V; Stieglitz, Barry

2013-10-29

Xylose-utilizing, ethanol producing strains of Zymomonas mobilis with improved performance in medium comprising biomass hydrolysate were isolated using an adaptation process. Independently isolated strains were found to have independent mutations in the same coding region. Mutation in this coding may be engineered to confer the improved phenotype.

Xylose utilizing zymomonas mobilis with improved ethanol production in biomass hydrolysate medium

DOEpatents

Caimi, Perry G; Hitz, William D; Stieglitz, Barry; Viitanen, Paul V

2013-07-02

Xylose-utilizing, ethanol producing strains of Zymomonas mobilis with improved performance in medium comprising biomass hydrolysate were isolated using an adaptation process. Independently isolated strains were found to have independent mutations in the same coding region. Mutation in this coding may be engineered to confer the improved phenotype.

Xylose utilization in recombinant Zymomonas

DOEpatents

Kahsay, Robel Y; Qi, Min; Tao, Luan; Viitanen, Paul V; Yang, Jianjun

2013-01-07

Zymomonas expressing xylose isomerase from A. missouriensis was found to have improved xylose utilization, growth, and ethanol production when grown in media containing xylose. Xylose isomerases related to that of A. missouriensis were identified structurally through molecular phylogenetic and Profile Hidden Markov Model analyses, providing xylose isomerases that may be used to improve xylose utilization.

Zymomonas with improved xylose utilization

DOEpatents

Viitanen, Paul V [West Chester, PA; Tao, Luan [Havertown, PA; Zhang, Yuying [New Hope, PA; Caimi, Perry G [Kennett Square, PA; McCutchen, Carol M [Wilmington, DE; McCole, Laura [East Fallowfield, PA; Zhang, Min [Lakewood, CO; Chou, Yat-Chen [Lakewood, CO; Franden, Mary Ann [Centennial, CO

2011-08-16

Strains of Zymomonas were engineered by introducing a chimeric xylose isomerase gene that contains a mutant promoter of the Z. mobilis glyceraldehyde-3-phosphate dehydrogenase gene. The promoter directs increased expression of xylose isomerase, and when the strain is in addition engineered for expression of xylulokinase, transaldolase and transketolase, improved utilization of xylose is obtained.

Pre-treatment step with Leuconostoc mesenteroides or L. pseudomesenteroides strains removes furfural from Zymomonas mobilis ethanolic fermentation broth

USDA-ARS?s Scientific Manuscript database

Furfural (furan-2-carboxaldehyde), formed during dilute acid hydrolysis of biomass, is an inhibitor of growth and ethanol production by Zymomonas mobilis. The present study used a biological pre-treatment to reduce that amount of furfural in a model biofuel fermentation broth. The pre-treatment in...

Ethanol production by Escherichia coli strains co-expressing Zymomonas PDC and ADH genes

DOEpatents

Ingram, Lonnie O.; Conway, Tyrrell; Alterthum, Flavio

1991-01-01

A novel operon and plasmids comprising genes which code for the alcohol dehydrogenase and pyruvate decarboxylase activities of Zymomonas mobilis are described. Also disclosed are methods for increasing the growth of microorganisms or eukaryotic cells and methods for reducing the accumulation of undesirable metabolic products in the growth medium of microorganisms or cells.

Xylitol synthesis mutant of xylose-utilizing zymomonas for ethanol production

DOEpatents

Viitanen, Paul V.; Chou, Yat-Chen; McCutchen, Carol M.; Zhang, Min

2010-06-22

A strain of xylose-utilizing Zymomonas was engineered with a genetic modification to the glucose-fructose oxidoreductase gene resulting in reduced expression of GFOR enzyme activity. The engineered strain exhibits reduced production of xylitol, a detrimental by-product of xylose metabolism. It also consumes more xylose and produces more ethanol during mixed sugar fermentation under process-relevant conditions.

Zymomonas mobilis as a model system for production of biofuels and biochemicals

DOE PAGES

Yang, Shihui; Fei, Qiang; Zhang, Yaoping; ...

2016-09-15

Zymomonas mobilis is a natural ethanologen with many desirable industrial biocatalyst characteristics. In this review, we will discuss work to develop Z. mobilis as a model system for biofuel production from the perspectives of substrate utilization, development for industrial robustness, potential product spectrum, strain evaluation and fermentation strategies. Lastly, this review also encompasses perspectives related to classical genetic tools and emerging technologies in this context.

Zymomonas mobilis as a model system for production of biofuels and biochemicals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Shihui; Fei, Qiang; Zhang, Yaoping

Zymomonas mobilis is a natural ethanologen with many desirable industrial biocatalyst characteristics. In this review, we will discuss work to develop Z. mobilis as a model system for biofuel production from the perspectives of substrate utilization, development for industrial robustness, potential product spectrum, strain evaluation and fermentation strategies. Lastly, this review also encompasses perspectives related to classical genetic tools and emerging technologies in this context.

Pnp gene modification for improved xylose utilization in Zymomonas

DOEpatents

Caimi, Perry G G; Qi, Min; Tao, Luan; Viitanen, Paul V; Yang, Jianjun

2014-12-16

The endogenous pnp gene encoding polynucleotide phosphorylase in the Zymomonas genome was identified as a target for modification to provide improved xylose utilizing cells for ethanol production. The cells are in addition genetically modified to have increased expression of ribose-5-phosphate isomerase (RPI) activity, as compared to cells without this genetic modification, and are not limited in xylose isomerase activity in the absence of the pnp modification.

Identification of yeast and bacteria involved in the mezcal fermentation of Agave salmiana.

PubMed

Escalante-Minakata, P; Blaschek, H P; Barba de la Rosa, A P; Santos, L; De León-Rodríguez, A

2008-06-01

To identify the yeast and bacteria present in the mezcal fermentation from Agave salmiana. The restriction and sequence analysis of the amplified region, between 18S and 28S rDNA and 16S rDNA genes, were used for the identification of yeast and bacteria, respectively. Eleven different micro-organisms were identified in the mezcal fermentation. Three of them were the following yeast: Clavispora lusitaniae, Pichia fermentans and Kluyveromyces marxianus. The bacteria found were Zymomonas mobilis subsp. mobilis and Zymomonas mobilis subsp. pomaceae, Weissella cibaria, Weissella paramesenteroides, Lactobacillus pontis, Lactobacillus kefiri, Lactobacillus plantarum and Lactobacillus farraginis. The phylogenetic analysis of 16S rDNA and ITS sequences showed that microbial diversity present in mezcal is dominated by bacteria, mainly lactic acid bacteria species and Zymomonas mobilis. Pichia fermentans and K. marxianus could be micro-organisms with high potential for the production of some volatile compounds in mezcal. We identified the community of bacteria and yeast present in mezcal fermentation from Agave salmiana.

Continuous production of ethanol with Zymomonas mobilis growing on Jerusalem artichoke juice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allais, J.J.; Torres, E.F.; Baratti, J.

1987-04-01

Recent work from the authors laboratory has shown that, compared to yeasts, much higher ethanol productivity and yield can be obtained in batch or continuous cultures using the bacterium Zymomonas mobilis grown on fructose media. In batch culture, hydrolyzed Jerusalem artichoke juice with sugar concentrations ranging from 100 to 250 g/L can be converted efficiently to ethanol. The present work describes the conversion of the hydrolyzed juice to ethanol in continuous culture. The extraction and enzymatic hydrolysis of inulin from the tubers of Jerusalem artichoke is also reported.

The Zymomonas mobilis regulator hfq contributes to tolerance against multiple lignocellulosic pretreatment inhibitors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Shihui; Pelletier, Dale A; Lu, Tse-Yuan

Zymomonas mobilis produces near theoretical yields of ethanol and recombinant strains are candidate industrial microorganisms. To date, few studies have examined its responses to various stresses at the gene level. Hfq is a conserved bacterial member of the Sm-like family of RNA-binding proteins, coordinating a broad array of responses including multiple stress responses. In a previous study, we observed Z. mobilis ZM4 gene ZMO0347 showed higher expression under anaerobic, stationary phase compared to that of aerobic, stationary conditions. We have shown the utility of the pKNOCK suicide plasmid for mutant construction in Z. mobilis, and constructed a Gateway compatible expressionmore » plasmid for use in Z. mobilis for the first time. We have also used genetics to show Z. mobilis Hfq and S. cerevisiae Lsm proteins play important roles in resisting multiple, important industrially relevant inhibitors. The conserved nature of this global regulator offers the potential to apply insights from these fundamental studies for further industrial strain development.« less

Using the CRISPR/Cas9 system to eliminate native plasmids of Zymomonas mobilis ZM4.

PubMed

Cao, Qing-Hua; Shao, Huan-Huan; Qiu, Hui; Li, Tao; Zhang, Yi-Zheng; Tan, Xue-Mei

2017-03-01

The CRISPR/Cas system can be used to simply and efficiently edit the genomes of various species, including animals, plants, and microbes. Zymomonas mobilis ZM4 is a highly efficient, ethanol-producing bacterium that contains five native plasmids. Here, we constructed the pSUZM2a-Cas9 plasmid and a single-guide RNA expression plasmid. The pSUZM2a-Cas9 plasmid was used to express the Cas9 gene cloned from Streptococcus pyogenes CICC 10464. The single-guide RNA expression plasmid pUC-T7sgRNA, with a T7 promoter, can be used for the in vitro synthesis of single-guide RNAs. This system was successfully employed to knockout the upp gene of Escherichia coli and the replicase genes of native Z. mobilis plasmids. This is the first study to apply the CRISPR/Cas9 system of S. pyogenes to eliminate native plasmids in Z. mobilis. It provides a new method for plasmid curing and paves the way for the genomic engineering of Z. mobilis.

Fuel alcohol biosynthesis by Zymomonas anaerobia: optimization studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kosaric, N.; Ong, S.L.; Davnjak, Z.

1982-03-01

The optimum operating conditions for growth and ethanol production of Zymomonas anaerobia ATCC 29501 were established. The optimum pH range and temperature were found to be 5.0-6.0 and 35/sup 0/C, respectively. Based on the results obtained from the temperature optimization study, an Arrhenius-type temperature relationship for the specific growth rate was developed. The growth and ethanol production of this microbe also have been optimized in terms of concentrations of glucose, essential nutrients, and minerals. With optimum medium and operating conditions, an ethanol concentration of 96 g/L was obtained in 23h. Both growth and ethanol yield coefficients in dependence on initialmore » glucose concentrations were determined.« less

Fuel alcohol biosynthesis by Zymomonas anaerobia: optimization studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kosaric, N.; Ong, S.L.; Duvnjak, Z.

1982-03-01

The optimum operating conditions for growth and ethanol production of Zymomonas anaerobia ATCC 29501 were established. The optimum pH range and temperature were found to be 5.0-6.0 and 35 degrees C, respectively. Based on the results obtained from the temperature optimization study, an Arrhenius-type temperature relationship for the specific growth rate was developed. The growth and ethanol production of this microbe also have been optimized in terms of concentrations of glucose, essential nutrients, and minerals. With optimum medium and operating conditions, an ethanol concentration of 96 g/L was obtained in 23 hours. Both growth and ethanol yield coefficients in dependencemore » on initial glucose concentrations were determined. (Refs. 16).« less

Stable zymomonas mobilis xylose and arabinose fermenting strains

DOEpatents

Zhang, Min [Lakewood, CO; Chou, Yat-Chen [Taipei, TW

2008-04-08

The present invention briefly includes a transposon for stable insertion of foreign genes into a bacterial genome, comprising at least one operon having structural genes encoding enzymes selected from the group consisting of xylAxylB, araBAD and tal/tkt, and at least one promoter for expression of the structural genes in the bacterium, a pair of inverted insertion sequences, the operons contained inside the insertion sequences, and a transposase gene located outside of the insertion sequences. A plasmid shuttle vector for transformation of foreign genes into a bacterial genome, comprising at least one operon having structural genes encoding enzymes selected from the group consisting of xylAxylB, araBAD and tal/tkt, at least one promoter for expression of the structural genes in the bacterium, and at least two DNA fragments having homology with a gene in the bacterial genome to be transformed, is also provided.The transposon and shuttle vectors are useful in constructing significantly different Zymomonas mobilis strains, according to the present invention, which are useful in the conversion of the cellulose derived pentose sugars into fuels and chemicals, using traditional fermentation technology, because they are stable for expression in a non-selection medium.

Recombinant cells that highly express chromosomally-integrated heterologous genes

DOEpatents

Ingram, L.O.; Ohta, Kazuyoshi; Wood, B.E.

1998-10-13

Recombinant host cells are obtained that comprise (A) a heterologous, polypeptide-encoding polynucleotide segment, stably integrated into a chromosome, which is under transcriptional control of an endogenous promoter and (B) a mutation that effects increased expression of the heterologous segment, resulting in enhanced production by the host cells of each polypeptide encoded by that segment, relative to production of each polypeptide by the host cells in the absence of the mutation. The increased expression thus achieved is retained in the absence of conditions that select for cells displaying such increased expression. When the integrated segment comprises, for example, ethanol-production genes from an efficient ethanol producer like Zymomonas mobilis, recombinant Escherichia coli and other enteric bacterial cells within the present invention are capable of converting a wide range of biomass-derived sugars efficiently to ethanol. 13 figs.

Recombinant cells that highly express chromosomally-integrated heterologous genes

DOEpatents

Ingram, Lonnie O.; Ohta, Kazuyoshi; Wood, Brent E.

1998-01-01

Recombinant host cells are obtained that comprise (A) a heterologous, polypeptide-encoding polynucleotide segment, stably integrated into a chromosome, which is under transcriptional control of an endogenous promoter and (B) a mutation that effects increased expression of the heterologous segment, resulting in enhanced production by the host cells of each polypeptide encoded by that segment, relative to production of each polypeptide by the host cells in the absence of the mutation. The increased expression thus achieved is retained in the absence of conditions that select for cells displaying such increased expression. When the integrated segment comprises, for example, ethanol-production genes from an efficient ethanol producer like Zymomonas mobilis, recombinant Escherichia coli and other enteric bacterial cells within the present invention are capable of converting a wide range of biomass-derived sugars efficiently to ethanol.

Recombinant cells that highly express chromosomally-integrated heterologous gene

DOEpatents

Ingram, Lonnie O.; Ohta, Kazuyoshi; Wood, Brent E.

2007-03-20

Recombinant host cells are obtained that comprise (A) a heterologous, polypeptide-encoding polynucleotide segment, stably integrated into a chromosome, which is under transcriptional control of an endogenous promoter and (B) a mutation that effects increased expression of the heterologous segment, resulting in enhanced production by the host cells of each polypeptide encoded by that segment, relative to production of each polypeptide by the host cells in the absence of the mutation. The increased expression thus achieved is retained in the absence of conditions that select for cells displaying such increased expression. When the integrated segment comprises, for example, ethanol-production genes from an efficient ethanol producer like Zymomonas mobilis, recombinant Escherichia coli and other enteric bacterial cells within the present invention are capable of converting a wide range of biomass-derived sugars efficiently to ethanol.

Recombinant cells that highly express chromosomally-integrated heterologous genes

DOEpatents

Ingram, Lonnie O.; Ohta, Kazuyoshi; Wood, Brent E.

2000-08-22

Recombinant host cells are obtained that comprise (A) a heterologous, polypeptide-encoding polynucleotide segment, stably integrated into a chromosome, which is under transcriptional control of an endogenous promoter and (B) a mutation that effects increased expression of the heterologous segment, resulting in enhanced production by the host cells of each polypeptide encoded by that segment, relative to production of each polypeptide by the host cells in the absence of the mutation. The increased expression thus achieved is retained in the absence of conditions that select for cells displaying such increased expression. When the integrated segment comprises, for example, ethanol-production genes from an efficient ethanol producer like Zymomonas mobilis, recombinant Escherichia coli and other enteric bacterial cells within the present invention are capable of converting a wide range of biomass-derived sugars efficiently to ethanol.

Transcriptome profiling of Zymomonas mobilis under furfural stress.

PubMed

He, Ming-xiong; Wu, Bo; Shui, Zong-xia; Hu, Qi-chun; Wang, Wen-guo; Tan, Fu-rong; Tang, Xiao-yu; Zhu, Qi-li; Pan, Ke; Li, Qing; Su, Xiao-hong

2012-07-01

Furfural from lignocellulosic hydrolysates is the prevalent inhibitor to microorganisms during cellulosic ethanol production, but the molecular mechanisms of tolerance to this inhibitor in Zymomonas mobilis are still unclear. In this study, genome-wide transcriptional responses to furfural were investigated in Z. mobilis using microarray analysis. We found that 433 genes were differentially expressed in response to furfural. Furfural up- or down-regulated genes related to cell wall/membrane biogenesis, metabolism, and transcription. However, furfural has a subtle negative effect on Entner-Doudoroff pathway mRNAs. Our results revealed that furfural had effects on multiple aspects of cellular metabolism at the transcriptional level and that membrane might play important roles in response to furfural. This research has provided insights into the molecular response to furfural in Z. mobilis, and it will be helpful to construct more furfural-resistant strains for cellulosic ethanol production.

Impact of expression of EMP enzymes on glucose metabolism in Zymomonas mobilis.

PubMed

Chen, Rachel Ruizhen; Agrawal, Manoj; Mao, Zichao

2013-06-01

Zymomonas mobilis is the only known microorganism that utilizes the Entner-Doudoroff (ED) pathway anaerobically. In this work, we investigated whether the overexpression of a phosphofructokinase (PFK), the only missing Embden-Meyerhof-Parnas (EMP) pathway enzyme, could establish the pathway in this organism. Introduction of a pyrophosphate-dependent PFK, along with co-expression of homologous fructose-1,6-bisphosphate aldolase and triosephosphate isomerase, did not result in an EMP flux to any appreciable level. However, the metabolism of glucose was impacted significantly. Eight percent of glucose was metabolized to form a new metabolite, dihydroxyacetone. Reducing flux through the ED pathway by as much as 40 % through antisense of a key enzyme, ED aldolase, did not result in a fully functional EMP pathway, suggesting that the ED pathway, especially the lower arm, downstream from glyceraldehyde-3-phosphate, is very rigid, possibly due to redox balance.

Detrimental effect of increasing sugar concentrations on ethanol production from maize or decorticated sorghum mashes fermented with Saccharomyces cerevisiae or Zymomonas mobilis: biofuels and environmental biotechnology.

PubMed

Pérez-Carrillo, Esther; Luisa Cortés-Callejas, M; Sabillón-Galeas, Luis E; Montalvo-Villarreal, Jorge L; Canizo, Jesica R; Georgina Moreno-Zepeda, M; Serna-Saldivar, Sergio O

2011-02-01

The efficiency of ethanol fermentation, as affected by grain source (maize and decorticated red sorghum), total sugar concentration (13 or 20° Plato) and type of microorganism (Saccharomyces cerevisiae or Zymomonas mobilis) was studied. Maize mashes yielded 0.32 l ethanol kg(-1) ground grain whereas mashes prepared with decorticated red sorghum produced 0.28 l ethanol kg(-1). Both microorganisms yielded similar amounts of ethanol. However, high-gravity mashes (20° Plato) yielded lower amounts of ethanol compared to counterparts adjusted to 13° Plato (0.28 vs. 0.22 l ethanol kg(-1) ground grains). In decorticated sorghum mashes adjusted to 20° P, Z. mobilis produced 40 ml kg(-1) more ethanol compared to S. cerevisiae. In addition, Z. mobilis had a lower dependency on nitrogenous compounds.

Crystal structure of cbbF from Zymomonas mobilis and its functional implication

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hwang, Hyo-Jeong; Park, Suk-Youl; Kim, Jeong-Sun, E-mail: jsunkim@chonnam.ac.kr

2014-02-28

Highlights: • The crystal structure of one cbbF from Zymomonas mobilis was revealed. • Scores of residues form two secondary structures with a non-polar protruded residue. • It exists as a dimeric form in solution. - Abstract: A phosphate group at the C1-atom of inositol-monophosphate (IMP) and fructose-1,6-bisphosphate (FBP) is hydrolyzed by a phosphatase IMPase and FBPase in a metal-dependent way, respectively. The two enzymes are almost indiscernible from each other because of their highly similar sequences and structures. Metal ions are bound to residues on the β1- and β2-strands and one mobile loop. However, FBP has another phosphate andmore » FBPases exist as a higher oligomeric state, which may discriminate FBPases from IMPases. There are three genes annotated as FBPases in Zymomonas mobilis, termed also cbbF (ZmcbbF). The revealed crystal structure of one ZmcbbF shows a globular structure formed by five stacked layers. Twenty-five residues in the middle of the sequence form an α-helix and a β-strand, which occupy one side of the catalytic site. A non-polar Leu residue among them is protruded to the active site, pointing out unfavorable access of a bulky charged group to this side. In vitro assays have shown its dimeric form in solution. Interestingly, two β-strands of β1 and β2 are disordered in the ZmcbbF structure. These data indicate that ZmcbbF might structurally belong to IMPase, and imply that its active site would be reorganized in a yet unreported way.« less

Yat-Chen Chou | NREL

Science.gov Websites

Patents "Xylitol synthesis mutant of xylose-utilizing Zymomonas for ethanol production," U.S . Patent No. 7,741,119 (2010) "Ethanol production using xylitol synthesis mutant of xylose-utilizing formulation using cellobiohydrolase-1 from Penicillium funiculosum," U.S. Patent No. 7,449,550 (2008

Ethanol production in recombinant hosts

DOEpatents

Ingram, Lonnie O'Neal; Barbosa-Alleyne, Maria D.

2005-02-01

The subject invention concerns the transformation of Gram-positive bacteria with heterologous genes which confer upon these microbes the ability to produce ethanol as a fermentation product. Specifically exemplified is the transformation of bacteria with genes, obtainable from Zymomonas mobilis, which encode pyruvate decarboxylase and alcohol dehydrogenase.

Ethanol production in gram-positive microbes

DOEpatents

Ingram, Lonnie O'Neal; Barbosa-Alleyne, Maria D. F.

1999-01-01

The subject invention concerns the transformation of Gram-positive bacteria with heterologous genes which confer upon these microbes the ability to produce ethanol as a fermentation product. Specifically exemplified is the transformation of bacteria with genes, obtainable from Zymomonas mobilis, which encode pyruvate decarboxylase and alcohol dehydrogenase.

Ethanol production in Gram-positive microbes

DOEpatents

Ingram, Lonnie O'Neal; Barbosa-Alleyne, Maria D. F.

1996-01-01

The subject invention concerns the transformation of Gram-positive bacteria with heterologous genes which confer upon these microbes the ability to produce ethanol as a fermentation product. Specifically exemplified is the transformation of bacteria with genes, obtainable from Zymomonas mobilis, which encode pyruvate decarboxylase and alcohol dehydrogenase.

Influence of the presence of Zymomonas anaerobia on the conversion of cellobiose, glucose, and xylose to ethanol by Clostridium saccharolyticum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Asther, M.; Khan, A.W.

1984-01-01

To convert sugar mixtures containing cellobiose, glucose, and xylose to ethanol in a single step, the possibility of using a coculture consisting of Clostridium saccharolyticum and Zymomonas anaerobia was studied. In monoculture, C. saccharolyticum utilized all three sugars; however, it preferentially utilized glucose and produced acetic acid in addition to ethanol. The formation of acetic acid from the metabolism of glucose inhibited the growth of C. saccharolyticum and, consequently, the utilization of cellobiose and xylose. In monoculture, Z. anaerobia utilized glucose at a rate of 50 g/L day, but it did not ferment cellobiose or xylose. In coculture, Z. anaerobiamore » converted most of the glucose to ethanol during the lag phase of growth of C. saccharolyticum, which then converted cellobiose and xylose to ethanol. The use of this coculture increased both the rate and the efficiency of the conversion of these three sugars to ethanol, and produced relatively small amounts of acetic acid.« less

Pre-treatment step with Leuconostoc mesenteroides or L. pseudomesenteroides strains removes furfural from Zymomonas mobilis ethanolic fermentation broth.

PubMed

Hunter, William J; Manter, Daniel K

2014-10-01

Furfural is an inhibitor of growth and ethanol production by Zymomonas mobilis. This study used a naturally occurring (not GMO) biological pre-treatment to reduce that amount of furfural in a model fermentation broth. Pre-treatment involved inoculating and incubating the fermentation broth with strains of Leuconostoc mesenteroides or Leuconostoc pseudomesenteroides. The Leuconostoc strains converted furfural to furfuryl alcohol without consuming large amounts of dextrose in the process. Coupling this pre-treatment to ethanolic fermentation reduced furfural in the broth and improved growth, dextrose uptake and ethanol formation. Pre-treatment permitted ethanol formation in the presence of 5.2 g L(-1) furfural, which was otherwise inhibitive. The pre-treatment and presence of the Leuconostoc strains in the fermentation broth did not interfere with Z. mobilis ethanolic fermentation or the amounts of ethanol produced. The method suggests a possible technique for reducing the effect that furfural has on the production of ethanol for use as a biofuel. Published by Elsevier Ltd.

Improving furfural tolerance of Zymomonas mobilis by rewiring a sigma factor RpoD protein.

PubMed

Tan, Fu-Rong; Dai, Li-Chun; Wu, Bo; Qin, Han; Shui, Zong-Xia; Wang, Jing-Li; Zhu, Qi-Li; Hu, Qi-Chun; Ruan, Zhi-Yong; He, Ming-Xiong

2015-06-01

Furfural from lignocellulosic hydrolysates is the key inhibitor for bio-ethanol fermentation. In this study, we report a strategy of improving the furfural tolerance in Zymomonas mobilis on the transcriptional level by engineering its global transcription sigma factor (σ(70), RpoD) protein. Three furfural tolerance RpoD mutants (ZM4-MF1, ZM4-MF2, and ZM4-MF3) were identified from error-prone PCR libraries. The best furfural-tolerance strain ZM4-MF2 reached to the maximal cell density (OD600) about 2.0 after approximately 30 h, while control strain ZM4-rpoD reached its highest cell density of about 1.3 under the same conditions. ZM4-MF2 also consumed glucose faster and yield higher ethanol; expression levels and key Entner-Doudoroff (ED) pathway enzymatic activities were also compared to control strain under furfural stress condition. Our results suggest that global transcription machinery engineering could potentially be used to improve stress tolerance and ethanol production in Z. mobilis.

Purification, crystallization and X-ray crystallographic analysis of a putative exopolyphosphatase from Zymomonas mobilis

PubMed Central

Zhang, Aili; Guo, Erhong; Qian, Lanfang; Tang, Nga-Yeung; Watt, Rory M.; Bartlam, Mark

2016-01-01

Exopolyphosphatase (PPX) enzymes degrade inorganic polyphosphate (poly-P), which is essential for the survival of microbial cells in response to external stresses. In this study, a putative exopolyphosphatase from Zymomonas mobilis (ZmPPX) was crystallized. Crystals of the wild-type enzyme diffracted to 3.3 Å resolution and could not be optimized further. The truncation of 29 amino acids from the N-terminus resulted in crystals that diffracted to 1.8 Å resolution. The crystals belonged to space group C2, with unit-cell parameters a = 122.0, b = 47.1, c = 89.5 Å, α = γ = 90, β = 124.5°. An active-site mutant that crystallized in the same space group and with similar unit-cell parameters diffracted to 1.56 Å resolution. One molecule was identified per asymmetric unit. Analytical ultracentrifugation confirmed that ZmPPX forms a dimer in solution. It was confirmed that ZmPPX possesses exopolyphosphatase activity against a synthetic poly-P substrate. PMID:26919520

Purification, crystallization and X-ray crystallographic analysis of a putative exopolyphosphatase from Zymomonas mobilis.

PubMed

Zhang, Aili; Guo, Erhong; Qian, Lanfang; Tang, Nga-Yeung; Watt, Rory M; Bartlam, Mark

2016-03-01

Exopolyphosphatase (PPX) enzymes degrade inorganic polyphosphate (poly-P), which is essential for the survival of microbial cells in response to external stresses. In this study, a putative exopolyphosphatase from Zymomonas mobilis (ZmPPX) was crystallized. Crystals of the wild-type enzyme diffracted to 3.3 Å resolution and could not be optimized further. The truncation of 29 amino acids from the N-terminus resulted in crystals that diffracted to 1.8 Å resolution. The crystals belonged to space group C2, with unit-cell parameters a = 122.0, b = 47.1, c = 89.5 Å, α = γ = 90, β = 124.5°. An active-site mutant that crystallized in the same space group and with similar unit-cell parameters diffracted to 1.56 Å resolution. One molecule was identified per asymmetric unit. Analytical ultracentrifugation confirmed that ZmPPX forms a dimer in solution. It was confirmed that ZmPPX possesses exopolyphosphatase activity against a synthetic poly-P substrate.

Ethanol production in Gram-positive microbes

DOEpatents

Ingram, L.O.; Barbosa-Alleyne, M.D.F.

1999-06-29

The subject invention concerns the transformation of Gram-positive bacteria with heterologous genes which confer upon these microbes the ability to produce ethanol as a fermentation product. Specifically exemplified is the transformation of bacteria with genes, obtainable from Zymomonas mobilis, which encode pyruvate decarboxylase and alcohol dehydrogenase. 2 figs.

Ethanol production in Gram-positive microbes

DOEpatents

Ingram, L.O.; Barbosa-Alleyne, M.D.F.

1996-01-09

The subject invention concerns the transformation of Gram-positive bacteria with heterologous genes which confer upon these microbes the ability to produce ethanol as a fermentation product. Specifically exemplified is the transformation of bacteria with genes, obtainable from Zymomonas mobilis, which encode pyruvate decarboxylase and alcohol dehydrogenase. 2 figs.

Transcriptome analysis of Zymomonas mobilis ZM4 reveals mechanisms of tolerance and detoxification of phenolic aldehyde inhibitors from lignocellulose pretreatment

USDA-ARS?s Scientific Manuscript database

Background: Phenolic aldehydes generated from lignocellulose pretreatment exhibited severe toxic inhibitions on microbial growth and fermentation. Numerous tolerance studies against furfural, 5-hydroxymethyl-2-furaldehyde (HMF), acetate, and ethanol were reported, but studies on inhibition of phenol...

A Highly Active Endo-Levanase BT1760 of a Dominant Mammalian Gut Commensal Bacteroides thetaiotaomicron Cleaves Not Only Various Bacterial Levans, but Also Levan of Timothy Grass

PubMed Central

Vija, Heiki; Aasamets, Anneli; Viigand, Katrin

2017-01-01

Bacteroides thetaiotaomicron, an abundant commensal of the human gut, degrades numerous complex carbohydrates. Recently, it was reported to grow on a β-2,6-linked polyfructan levan produced by Zymomonas mobilis degrading the polymer into fructooligosaccharides (FOS) with a cell surface bound endo-levanase BT1760. The FOS are consumed by B. thetaiotaomicron, but also by other gut bacteria, including health-promoting bifidobacteria and lactobacilli. Here we characterize biochemical properties of BT1760, including the activity of BT1760 on six bacterial levans synthesized by the levansucrase Lsc3 of Pseudomonas syringae pv. tomato, its mutant Asp300Asn, levansucrases of Zymomonas mobilis, Erwinia herbicola, Halomonas smyrnensis as well as on levan isolated from timothy grass. For the first time a plant levan is shown as a perfect substrate for an endo-fructanase of a human gut bacterium. BT1760 degraded levans to FOS with degree of polymerization from 2 to 13. At optimal reaction conditions up to 1 g of FOS were produced per 1 mg of BT1760 protein. Low molecular weight (<60 kDa) levans, including timothy grass levan and levan synthesized from sucrose by the Lsc3Asp300Asn, were degraded most rapidly whilst levan produced by Lsc3 from raffinose least rapidly. BT1760 catalyzed finely at human body temperature (37°C) and in moderately acidic environment (pH 5–6) that is typical for the gut lumen. According to differential scanning fluorimetry, the Tm of the endo-levanase was 51.5°C. All tested levans were sufficiently stable in acidic conditions (pH 2.0) simulating the gastric environment. Therefore, levans of both bacterial and plant origin may serve as a prebiotic fiber for B. thetaiotaomicron and contribute to short-chain fatty acids synthesis by gut microbiota. In the genome of Bacteroides xylanisolvens of human origin a putative levan degradation locus was disclosed. PMID:28103254

A Highly Active Endo-Levanase BT1760 of a Dominant Mammalian Gut Commensal Bacteroides thetaiotaomicron Cleaves Not Only Various Bacterial Levans, but Also Levan of Timothy Grass.

PubMed

Mardo, Karin; Visnapuu, Triinu; Vija, Heiki; Aasamets, Anneli; Viigand, Katrin; Alamäe, Tiina

2017-01-01

Bacteroides thetaiotaomicron, an abundant commensal of the human gut, degrades numerous complex carbohydrates. Recently, it was reported to grow on a β-2,6-linked polyfructan levan produced by Zymomonas mobilis degrading the polymer into fructooligosaccharides (FOS) with a cell surface bound endo-levanase BT1760. The FOS are consumed by B. thetaiotaomicron, but also by other gut bacteria, including health-promoting bifidobacteria and lactobacilli. Here we characterize biochemical properties of BT1760, including the activity of BT1760 on six bacterial levans synthesized by the levansucrase Lsc3 of Pseudomonas syringae pv. tomato, its mutant Asp300Asn, levansucrases of Zymomonas mobilis, Erwinia herbicola, Halomonas smyrnensis as well as on levan isolated from timothy grass. For the first time a plant levan is shown as a perfect substrate for an endo-fructanase of a human gut bacterium. BT1760 degraded levans to FOS with degree of polymerization from 2 to 13. At optimal reaction conditions up to 1 g of FOS were produced per 1 mg of BT1760 protein. Low molecular weight (<60 kDa) levans, including timothy grass levan and levan synthesized from sucrose by the Lsc3Asp300Asn, were degraded most rapidly whilst levan produced by Lsc3 from raffinose least rapidly. BT1760 catalyzed finely at human body temperature (37°C) and in moderately acidic environment (pH 5-6) that is typical for the gut lumen. According to differential scanning fluorimetry, the Tm of the endo-levanase was 51.5°C. All tested levans were sufficiently stable in acidic conditions (pH 2.0) simulating the gastric environment. Therefore, levans of both bacterial and plant origin may serve as a prebiotic fiber for B. thetaiotaomicron and contribute to short-chain fatty acids synthesis by gut microbiota. In the genome of Bacteroides xylanisolvens of human origin a putative levan degradation locus was disclosed.

Biological conversion system

DOEpatents

Scott, C.D.

A system for bioconversion of organic material comprises a primary bioreactor column wherein a biological active agent (zymomonas mobilis) converts the organic material (sugar) to a product (alcohol), a rejuvenator column wherein the biological activity of said biological active agent is enhanced, and means for circulating said biological active agent between said primary bioreactor column and said rejuvenator column.

Genetic improvement of Escherichia coli for ethanol production: Chromosomal integration of Zymomonas mobilis genes encoding pyruvate decarboxylase and alcohol dehydrogenase II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohta, Kazuyoshi; Beall, D.S.; Mejia, J.P.

1991-04-01

Zymomonas mobilis genes for pyruvate decarboxylase (pdc) and alcohol dehydrogenase II (adhB) were integrated into the Escherichia coli chromosome within or near the pyruvate formate-lyase gene (pfl). Integration improved the stability of the Z. mobilis genes in E. coli, but further selection was required to increase expression. Spontaneous mutants were selected for resistance to high levels of chloramphenicol that also expressed high levels of the Z. mobilis genes. Analogous mutants were selected for increased expression of alcohol dehydrogenase on aldehyde indicator plates. These mutants were functionally equivalent to the previous plasmid-based strains for the fermentation of xylose and glucose tomore » ethanol. Ethanol concentrations of 54.4 and 41.6 g/liter were obtained from 10% glucose and 8% xylose, respectively. The efficiency of conversion exceeded theoretical limits (0.51 g of ethanol/g of sugar) on the basis of added sugars because of the additional production of ethanol from the catabolism of complex nutrients. Further mutations were introduced to inactivate succinate production (frd) and to block homologous recombination (recA).« less

N 2 gas is an effective fertilizer for bioethanol production by Zymomonas mobilis

DOE PAGES

Kremer, Timothy A.; LaSarre, Breah; Posto, Amanda L.; ...

2015-02-02

A nascent cellulosic ethanol industry is struggling to become cost-competitive against corn ethanol and gasoline. Millions of dollars are spent on nitrogen supplements to make up for the low nitrogen content of the cellulosic feedstock. In this paper, we show for the first time to our knowledge that the ethanol-producing bacterium, Zymomonas mobilis, can use N 2 gas in lieu of traditional nitrogen supplements. Despite being an electron-intensive process, N 2 fixation by Z. mobilis did not divert electrons away from ethanol production, as the ethanol yield was greater than 97% of the theoretical maximum. In a defined medium, Z.more » mobilis produced ethanol 50% faster per cell and generated half the unwanted biomass when supplied N 2 instead of ammonium. In a cellulosic feedstock-derived medium, Z. mobilis achieved a similar cell density and a slightly higher ethanol yield when supplied N 2 instead of the industrial nitrogen supplement, corn steep liquor. Finally, we estimate that N 2-utilizing Z. mobilis could save a cellulosic ethanol production facility more than $1 million/y.« less

Zymomonas mobilis: a novel platform for future biorefineries.

PubMed

He, Ming Xiong; Wu, Bo; Qin, Han; Ruan, Zhi Yong; Tan, Fu Rong; Wang, Jing Li; Shui, Zong Xia; Dai, Li Chun; Zhu, Qi Li; Pan, Ke; Tang, Xiao Yu; Wang, Wen Guo; Hu, Qi Chun

2014-01-01

Biosynthesis of liquid fuels and biomass-based building block chemicals from microorganisms have been regarded as a competitive alternative route to traditional. Zymomonas mobilis possesses a number of desirable characteristics for its special Entner-Doudoroff pathway, which makes it an ideal platform for both metabolic engineering and commercial-scale production of desirable bio-products as the same as Escherichia coli and Saccharomyces cerevisiae based on consideration of future biomass biorefinery. Z. mobilis has been studied extensively on both fundamental and applied level, which will provide a basis for industrial biotechnology in the future. Furthermore, metabolic engineering of Z. mobilis for enhancing bio-ethanol production from biomass resources has been significantly promoted by different methods (i.e. mutagenesis, adaptive laboratory evolution, specific gene knock-out, and metabolic engineering). In addition, the feasibility of representative metabolites, i.e. sorbitol, bionic acid, levan, succinic acid, isobutanol, and isobutanol produced by Z. mobilis and the strategies for strain improvements are also discussed or highlighted in this paper. Moreover, this review will present some guidelines for future developments in the bio-based chemical production using Z. mobilis as a novel industrial platform for future biofineries.

Open fermentative production of fuel ethanol from food waste by an acid-tolerant mutant strain of Zymomonas mobilis.

PubMed

Ma, Kedong; Ruan, Zhiyong; Shui, Zongxia; Wang, Yanwei; Hu, Guoquan; He, Mingxiong

2016-03-01

The aim of present study was to develop a process for open ethanol fermentation from food waste using an acid-tolerant mutant of Zymomonas mobilis (ZMA7-2). The mutant showed strong tolerance to acid condition of food waste hydrolysate and high ethanol production performance. By optimizing fermentation parameters, ethanol fermentation with initial glucose concentration of 200 g/L, pH value around 4.0, inoculum size of 10% and without nutrient addition was considered as best conditions. Moreover, the potential of bench scales fermentation and cell reusability was also examined. The fermentation in bench scales (44 h) was faster than flask scale (48 h), and the maximum ethanol concentration and ethanol yield (99.78 g/L, 0.50 g/g) higher than that of flask scale (98.31 g/L, 0.49 g/g). In addition, the stable cell growth and ethanol production profile in five cycles successive fermentation was observed, indicating the mutant was suitable for industrial ethanol production. Copyright © 2015 Elsevier Ltd. All rights reserved.

N2 gas is an effective fertilizer for bioethanol production by Zymomonas mobilis

PubMed Central

Kremer, Timothy A.; LaSarre, Breah; Posto, Amanda L.; McKinlay, James B.

2015-01-01

A nascent cellulosic ethanol industry is struggling to become cost-competitive against corn ethanol and gasoline. Millions of dollars are spent on nitrogen supplements to make up for the low nitrogen content of the cellulosic feedstock. Here we show for the first time to our knowledge that the ethanol-producing bacterium, Zymomonas mobilis, can use N2 gas in lieu of traditional nitrogen supplements. Despite being an electron-intensive process, N2 fixation by Z. mobilis did not divert electrons away from ethanol production, as the ethanol yield was greater than 97% of the theoretical maximum. In a defined medium, Z. mobilis produced ethanol 50% faster per cell and generated half the unwanted biomass when supplied N2 instead of ammonium. In a cellulosic feedstock-derived medium, Z. mobilis achieved a similar cell density and a slightly higher ethanol yield when supplied N2 instead of the industrial nitrogen supplement, corn steep liquor. We estimate that N2-utilizing Z. mobilis could save a cellulosic ethanol production facility more than $1 million/y. PMID:25646422

Insights into Acetate Toxicity in Zymomonas mobilis 8b using Different Substrates

DOE PAGES

Yang, Shihui; Franden, M. A.; Brown, S. D.; ...

2014-09-30

The lignocellulosic biomass is a promising renewable feedstock for biofuel production. Acetate is one of the major inhibitors liberated from hemicelluloses during hydrolysis. Likewise, an understanding of the toxic effects of acetate on the fermentation microorganism and the efficient utilization of mixed sugars of glucose and xylose in the presence of hydrolysate inhibitors is crucial for economic biofuel production.

Zymomonas mobilis: a novel platform for future biorefineries

PubMed Central

2014-01-01

Biosynthesis of liquid fuels and biomass-based building block chemicals from microorganisms have been regarded as a competitive alternative route to traditional. Zymomonas mobilis possesses a number of desirable characteristics for its special Entner-Doudoroff pathway, which makes it an ideal platform for both metabolic engineering and commercial-scale production of desirable bio-products as the same as Escherichia coli and Saccharomyces cerevisiae based on consideration of future biomass biorefinery. Z. mobilis has been studied extensively on both fundamental and applied level, which will provide a basis for industrial biotechnology in the future. Furthermore, metabolic engineering of Z. mobilis for enhancing bio-ethanol production from biomass resources has been significantly promoted by different methods (i.e. mutagenesis, adaptive laboratory evolution, specific gene knock-out, and metabolic engineering). In addition, the feasibility of representative metabolites, i.e. sorbitol, bionic acid, levan, succinic acid, isobutanol, and isobutanol produced by Z. mobilis and the strategies for strain improvements are also discussed or highlighted in this paper. Moreover, this review will present some guidelines for future developments in the bio-based chemical production using Z. mobilis as a novel industrial platform for future biofineries. PMID:25024744

Improvement of ethanol productivity and energy efficiency by degradation of inhibitors using recombinant Zymomonas mobilis (pHW20a-fdh).

PubMed

Dong, Hong-Wei; Fan, Li-Qiang; Luo, Zichen; Zhong, Jian-Jiang; Ryu, Dewey D Y; Bao, Jie

2013-09-01

Toxic compounds, such as formic acid, furfural, and hydroxymethylfurfural (HMF) generated during pretreatment of corn stover (CS) at high temperature and low pH, inhibit growth of Zymomonas mobilis and lower the conversion efficiency of CS to biofuel and other products. The inhibition of toxic compounds is considered as one of the major technical barriers in the lignocellulose bioconversion. In order to detoxify and/or degrade these toxic compounds by the model ethanologenic strain Z. mobilis itself in situ the fermentation medium, we constructed a recombinant Z. mobilis ZM4 (pHW20a-fdh) strain that is capable of degrading toxic inhibitor, formate. This is accomplished by cloning heterologous formate dehydrogenase gene (fdh) from Saccharomyces cerevisiae and by coupling this reaction of NADH regeneration reaction system with furfural and HMF degradation in the recombinant Z. mobilis strain. The NADH regeneration reaction also improved both the energy efficiency and cell physiological activity of the recombinant organism, which were definitely confirmed by the improved cell growth, ethanol yield, and ethanol productivity during fermentation with CS hydrolysate. Copyright © 2013 Wiley Periodicals, Inc.

Metabolic engineering of Zymomonas mobilis for 2,3-butanediol production from lignocellulosic biomass sugars

DOE PAGES

Yang, Shihui; Mohagheghi, Ali; Franden, Mary Ann; ...

2016-09-02

To develop pathways for advanced biofuel production, and to understand the impact of host metabolism and environmental conditions on heterologous pathway engineering for economic advanced biofuels production from biomass, we seek to redirect the carbon flow of the model ethanologen Zymomonas mobilis to produce desirable hydrocarbon intermediate 2,3-butanediol (2,3-BDO). 2,3-BDO is a bulk chemical building block, and can be upgraded in high yields to gasoline, diesel, and jet fuel. 2,3-BDO biosynthesis pathways from various bacterial species were examined, which include three genes encoding acetolactate synthase, acetolactate decarboxylase, and butanediol dehydrogenase. Bioinformatics analysis was carried out to pinpoint potential bottlenecks formore » high 2,3-BDO production. Different combinations of 2,3-BDO biosynthesis metabolic pathways using genes from different bacterial species have been constructed. Our results demonstrated that carbon flux can be deviated from ethanol production into 2,3-BDO biosynthesis, and all three heterologous genes are essential to efficiently redirect pyruvate from ethanol production for high 2,3-BDO production in Z. mobilis. The down-selection of best gene combinations up to now enabled Z. mobilis to reach the 2,3-BDO production of more than 10 g/L from glucose and xylose, as well as mixed C6/C5 sugar streams derived from the deacetylation and mechanical refining process. In conclusion, this study confirms the value of integrating bioinformatics analysis and systems biology data during metabolic engineering endeavors, provides guidance for value-added chemical production in Z. mobilis, and reveals the interactions between host metabolism, oxygen levels, and a heterologous 2,3-BDO biosynthesis pathway. Taken together, this work provides guidance for future metabolic engineering efforts aimed at boosting 2,3-BDO titer anaerobically.« less

Metabolic engineering of Zymomonas mobilis for 2,3-butanediol production from lignocellulosic biomass sugars

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Shihui; Mohagheghi, Ali; Franden, Mary Ann

To develop pathways for advanced biofuel production, and to understand the impact of host metabolism and environmental conditions on heterologous pathway engineering for economic advanced biofuels production from biomass, we seek to redirect the carbon flow of the model ethanologen Zymomonas mobilis to produce desirable hydrocarbon intermediate 2,3-butanediol (2,3-BDO). 2,3-BDO is a bulk chemical building block, and can be upgraded in high yields to gasoline, diesel, and jet fuel. 2,3-BDO biosynthesis pathways from various bacterial species were examined, which include three genes encoding acetolactate synthase, acetolactate decarboxylase, and butanediol dehydrogenase. Bioinformatics analysis was carried out to pinpoint potential bottlenecks formore » high 2,3-BDO production. Different combinations of 2,3-BDO biosynthesis metabolic pathways using genes from different bacterial species have been constructed. Our results demonstrated that carbon flux can be deviated from ethanol production into 2,3-BDO biosynthesis, and all three heterologous genes are essential to efficiently redirect pyruvate from ethanol production for high 2,3-BDO production in Z. mobilis. The down-selection of best gene combinations up to now enabled Z. mobilis to reach the 2,3-BDO production of more than 10 g/L from glucose and xylose, as well as mixed C6/C5 sugar streams derived from the deacetylation and mechanical refining process. In conclusion, this study confirms the value of integrating bioinformatics analysis and systems biology data during metabolic engineering endeavors, provides guidance for value-added chemical production in Z. mobilis, and reveals the interactions between host metabolism, oxygen levels, and a heterologous 2,3-BDO biosynthesis pathway. Taken together, this work provides guidance for future metabolic engineering efforts aimed at boosting 2,3-BDO titer anaerobically.« less

Can Zymomonas mobilis Substitute Saccharomyces cerevisiae in Cereal Dough Leavening?

PubMed Central

Musatti, Alida; Mapelli, Chiara

2018-01-01

Baker’s yeast intolerance is rising among Western populations, where Saccharomyces cerevisiae is spread in fermented food and food components. Zymomonas mobilis is a bacterium commonly used in tropical areas to produce alcoholic beverages, and it has only rarely been considered for dough leavening probably because it only ferments glucose, fructose and sucrose, which are scarcely present in flour. However, through alcoholic fermentation, similarly to S. cerevisiae, it provides an equimolar mixture of ethanol and CO2 that can rise a dough. Here, we propose Z. mobilis as a new leavening agent, as an alternative to S. cerevisiae, overcoming its technological limit with different strategies: (1) adding glucose to the dough formulation; and (2) exploiting the maltose hydrolytic activity of Lactobacillus sanfranciscensis associated with Z. mobilis. CO2 production, dough volume increase, pH value, microbial counts, sugars consumption and ethanol production were monitored. Results suggest that glucose addition to the dough lets Z. mobilis efficiently leaven a dough, while glucose released by L. sanfranciscensis is not so well fermented by Z. mobilis, probably due to the strong acidification. Nevertheless, the use of Z. mobilis as a leavening agent could contribute to increasing the variety of baked goods alternative to those leavened by S. cerevisiae. PMID:29659515

Development of a high-throughput method to evaluate the impact of inhibitory compounds from lignocellulosic hydrolysates on the growth of Zymomonas mobilis.

PubMed

Franden, Mary Ann; Pienkos, Philip T; Zhang, Min

2009-12-01

Overcoming the effects of hydrolysate toxicity towards ethanologens is a key technical barrier in the biochemical conversion process for biomass feedstocks to ethanol. Despite its importance, the complexity of the hydrolysate toxicity phenomena and the lack of systematic studies, analysis and tools surrounding this issue have blocked a full understanding of relationships involving toxic compounds in hydrolysates and their effects on ethanologen growth and fermentation. In this study, we developed a quantitative, high-throughput biological growth assay using an automated turbidometer to obtain detailed inhibitory kinetics for individual compounds present in lignocellulosic biomass hydrolysate. Information about prolonged lag time and final cell densities can also be obtained. The effects of furfural, hydroxymethylfurfural (HMF), acetate and ethanol on growth rate and final cell densities of Zymomonas mobilis 8b on glucose are presented. This method was also shown to be of value in toxicity studies of hydrolysate itself, despite the highly colored nature of this material. Using this approach, we can generate comprehensive inhibitory profiles with many individual compounds and develop models that predict and examine toxic effects in the complex mixture of hydrolysates, leading to the development of improved pretreatment and conditioning processes as well as fermentation organisms.

Biotransformation of pineapple juice sugars into dietetic derivatives by using a cell free oxidoreductase from Zymomonas mobilis together with commercial invertase.

PubMed

Aziz, M G; Michlmayr, H; Kulbe, K D; Del Hierro, A M

2011-01-05

An easy procedure for cell free biotransformation of pineapple juice sugars into dietetic derivatives was accomplished using a commercial invertase and an oxidoreductase from Zymomonas mobilis. First, pineapple juice sucrose was quantitatively converted into glucose and fructose by invertase, thus increasing the concentration of each monosaccharide in the original juice to almost twice. In a second step, glucose-fructose oxidoreductase (GFOR) transformed glucose into gluconolactone, and fructose into the low calorie sweetener sorbitol. The advantage of using GFOR is simultaneous reduction of fructose and oxidation of glucose, allowing the continuous regeneration of the essential coenzyme NADP(H), that is tightly bound to the enzyme. The yield of GFOR catalyzed sugar conversion depends on initial pH and control of pH during the reaction. At optimal conditions (pH control at 6.2) a maximum of 80% (w/v) sugar conversion was obtained. Without pH control, GFOR is inactivated rapidly due to gluconic acid formation. Therefore, conversion yields are relatively low at the natural pH of pineapple juice. The application of this process might be more advantageous on juices of other tropical fruits (papaya, jackfruit, mango) due to their naturally given higher pH. Copyright © 2010 Elsevier Inc. All rights reserved.

Evaluation and optimization of ethanol production from carob pod extract by Zymomonas mobilis using response surface methodology.

PubMed

Vaheed, Hossein; Shojaosadati, Seyed Abbas; Galip, Hasan

2011-01-01

In this research, ethanol production from carob pod extract (extract) using Zymomonas mobilis with medium optimized by Plackett-Burman (P-B) and response surface methodologies (RSM) was studied. Z. mobilis was recognized as useful for ethanol production from carob pod extract. The effects of initial concentrations of sugar, peptone, and yeast extract as well as agitation rate (rpm), pH, and culture time in nonhydrolyzed carob pod extract were investigated. Significantly affecting variables (P = 0.05) in the model obtained from RSM studies were: weights of bacterial inoculum, initial sugar, peptone, and yeast extract. Acid hydrolysis was useful to complete conversion of sugars to glucose and fructose. Nonhydrolyzed extract showed higher ethanol yield and residual sugar compared with hydrolyzed extract. Ethanol produced (g g(-1) initial sugar, as the response) was not significantly different (P = 0.05) when Z. mobilis performance was compared in hydrolyzed and nonhydrolyzed extract. The maximum ethanol of 0.34 ± 0.02 g g(-1) initial sugar was obtained at 30°C, initial pH 5.2, and 80 rpm, using concentrations (g per 50 mL culture media) of: inoculum bacterial dry weight, 0.017; initial sugar, 5.78; peptone, 0.43; yeast extract, 0.43; and culture time of 36 h.

Genetic engineering and improvement of a Zymomonas mobilis for arabinose utilization and its performance on pretreated corn stover hydrolyzate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chou, Yat -Chen; Linger, Jeffrey; Yang, Shihui

In this paper, a glucose, xylose and arabinose utilizing Zymomonas mobilis strain was constructed by incorporating arabinose catabolic pathway genes, araBAD encoding L-ribulokinase, L-arabinose isomerase and L-ribulose-5-phosphate- 4-epimerase in a glucose, xylose co-fermenting host, 8b, using a transposition integration approach. Further improvement on this arabinose-capable integrant, 33C was achieved by applying a second transposition to create a genomic knockout (KO) mutant library. Using arabinose as a sole carbon source and a selection pressure, the KO library was subjected to a growth-enrichment process involving continuous sub-culturing for over 120 generations. Strain 13-1-17, isolated from such process demonstrated significant improvement in metabolizingmore » arabinose in a dilute acid pretreated, saccharified corn stover slurry. Through Next Generation Sequencing (NGS) analysis, integration sites of the transposons were identified. Furthermore, multiple additional point mutations (SNPs: Single Nucleotide Polymorphisms) were discovered in 13-1-17, affecting genes araB and RpiB in the genome. Finally, we speculate that these mutations may have impacted the expression of the enzymes coded by these genes, ribulokinase and Ribose 5-P-isomerase, thus attributing to the improvement of the arabinose utilization.« less

Genetic engineering and improvement of a Zymomonas mobilis for arabinose utilization and its performance on pretreated corn stover hydrolyzate

DOE PAGES

Chou, Yat -Chen; Linger, Jeffrey; Yang, Shihui; ...

2015-04-28

In this paper, a glucose, xylose and arabinose utilizing Zymomonas mobilis strain was constructed by incorporating arabinose catabolic pathway genes, araBAD encoding L-ribulokinase, L-arabinose isomerase and L-ribulose-5-phosphate- 4-epimerase in a glucose, xylose co-fermenting host, 8b, using a transposition integration approach. Further improvement on this arabinose-capable integrant, 33C was achieved by applying a second transposition to create a genomic knockout (KO) mutant library. Using arabinose as a sole carbon source and a selection pressure, the KO library was subjected to a growth-enrichment process involving continuous sub-culturing for over 120 generations. Strain 13-1-17, isolated from such process demonstrated significant improvement in metabolizingmore » arabinose in a dilute acid pretreated, saccharified corn stover slurry. Through Next Generation Sequencing (NGS) analysis, integration sites of the transposons were identified. Furthermore, multiple additional point mutations (SNPs: Single Nucleotide Polymorphisms) were discovered in 13-1-17, affecting genes araB and RpiB in the genome. Finally, we speculate that these mutations may have impacted the expression of the enzymes coded by these genes, ribulokinase and Ribose 5-P-isomerase, thus attributing to the improvement of the arabinose utilization.« less

Effect of Brönsted acidic ionic liquid 1-(1-propylsulfonic)-3-methylimidazolium chloride on growth and co-fermentation of glucose, xylose and arabinose by Zymomonas mobilis AX101.

PubMed

Gyamerah, M; Ampaw-Asiedu, M; Mackey, J; Menezes, B; Woldesenbet, S

2018-06-01

The potential of large-scale lignocellulosic biomass hydrolysis to fermentable sugars using ionic liquids has increased interest in this green chemistry route to fermentation for fuel-ethanol production. The ionic liquid 1-(1-propylsulfonic)-3-methylimidazolium chloride compared to other reported ionic liquids has the advantage of hydrolysing lignocellulosic biomass to reducing sugars at catalytic concentrations (≤0·032 mol l -1 ) in a single step. However, effects of this ionic liquid on co-fermentation of glucose, xylose and arabinose to ethanol by recombinant Zymomonas mobilisAX101 has not been studied. Authentic glucose, xylose and arabinose were used to formulate fermentation media at varying catalytic 1-(1-propylsulfonic)-3-methylimidazolium chloride concentrations for batch co-fermentation of the sugars using Z. mobilisAX101. The results showed that at 0·008, 0·016 and 0·032 mol l -1 ionic liquid in the culture medium, cell growth decreased by 10, 27 and 67% respectively compared to the control. Ethanol yields were 62·6, 61·8, 50·5 and 23·1% for the control, 0·008, 0·016 and 0·032 mol l -1 ionic liquid respectively. The results indicate that lignocellulosic biomass hydrolysed using 0·008 mol l -1 of 1-(1-propylsulfonic)-3-methylimidazolium chloride would eliminate an additional separation step and provide a ready to use fermentation substrate. This is the first reported study of the effect of the Brönsted acidic ionic liquid 1-(1-propylsulfonic)-3-methylimidazolium chloride on growth and co-fermentation of glucose, xylose and arabinose by Zymomonas mobilisAX101 in batch culture. Growth on and co-fermentation of the sugars by Z. mobilisAX 101 with no significant inhibition by the ionic liquid at the same catalytic amounts of 0·008 mol l -1 used to hydrolyse lignocellulosic biomass to reducing sugars overcome two major hurdles that adversely affect the process economics of large-scale industrial cellulosic fuel ethanol production; the energy-intensive hydrolysis and ionic liquid separation steps. © 2018 The Society for Applied Microbiology.

Purification and characterization of an oxygen-labile, NAD-dependent alcohol dehydrogenase from Desulfovibrio gigas.

PubMed Central

Hensgens, C M; Vonck, J; Van Beeumen, J; van Bruggen, E F; Hansen, T A

1993-01-01

A NAD-dependent, oxygen-labile alcohol dehydrogenase was purified from Desulfovibrio gigas. It was decameric, with subunits of M(r) 43,000. The best substrates were ethanol (Km, 0.15 mM) and 1-propanol (Km, 0.28 mM). N-terminal amino acid sequence analysis showed that the enzyme belongs to the same family of alcohol dehydrogenases as Zymomonas mobilis ADH2 and Bacillus methanolicus MDH. Images PMID:8491707

Furfural-tolerant Zymomonas mobilis derived from error-prone PCR-based whole genome shuffling and their tolerant mechanism.

PubMed

Huang, Suzhen; Xue, Tingli; Wang, Zhiquan; Ma, Yuanyuan; He, Xueting; Hong, Jiefang; Zou, Shaolan; Song, Hao; Zhang, Minhua

2018-04-01

Furfural-tolerant strain is essential for the fermentative production of biofuels or chemicals from lignocellulosic biomass. In this study, Zymomonas mobilis CP4 was for the first time subjected to error-prone PCR-based whole genome shuffling, and the resulting mutants F211 and F27 that could tolerate 3 g/L furfural were obtained. The mutant F211 under various furfural stress conditions could rapidly grow when the furfural concentration reduced to 1 g/L. Meanwhile, the two mutants also showed higher tolerance to high concentration of glucose than the control strain CP4. Genome resequencing revealed that the F211 and F27 had 12 and 13 single-nucleotide polymorphisms. The activity assay demonstrated that the activity of NADH-dependent furfural reductase in mutant F211 and CP4 was all increased under furfural stress, and the activity peaked earlier in mutant than in control. Also, furfural level in the culture of F211 was also more rapidly decreased. These indicate that the increase in furfural tolerance of the mutants may be resulted from the enhanced NADH-dependent furfural reductase activity during early log phase, which could lead to an accelerated furfural detoxification process in mutants. In all, we obtained Z. mobilis mutants with enhanced furfural and high concentration of glucose tolerance, and provided valuable clues for the mechanism of furfural tolerance and strain development.

Flocculating Zymomonas mobilis is a promising host to be engineered for fuel ethanol production from lignocellulosic biomass.

PubMed

Zhao, Ning; Bai, Yun; Liu, Chen-Guang; Zhao, Xin-Qing; Xu, Jian-Feng; Bai, Feng-Wu

2014-03-01

Whereas Saccharomyces cerevisiae uses the Embden-Meyerhof-Parnas pathway to metabolize glucose, Zymomonas mobilis uses the Entner-Doudoroff (ED) pathway. Employing the ED pathway, 50% less ATP is produced, which could lead to less biomass being accumulated during fermentation and an improved yield of ethanol. Moreover, Z. mobilis cells, which have a high specific surface area, consume glucose faster than S. cerevisiae, which could improve ethanol productivity. We performed ethanol fermentations using these two species under comparable conditions to validate these speculations. Increases of 3.5 and 3.3% in ethanol yield, and 58.1 and 77.8% in ethanol productivity, were observed in ethanol fermentations using Z. mobilis ZM4 in media containing ∼100 and 200 g/L glucose, respectively. Furthermore, ethanol fermentation bythe flocculating Z. mobilis ZM401 was explored. Although no significant difference was observed in ethanol yield and productivity, the flocculation of the bacterial species enabled biomass recovery by cost-effective sedimentation, instead of centrifugation with intensive capital investment and energy consumption. In addition, tolerance to inhibitory byproducts released during biomass pretreatment, particularly acetic acid and vanillin, was improved. These experimental results indicate that Z. mobilis, particularly its flocculating strain, is superior to S. cerevisiae as a host to be engineered for fuel ethanol production from lignocellulosic biomass. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cloning, sequencing, and expression of the Zymomonas mobilis phosphoglycerate mutase gene (pgm) in Escherichia coli.

PubMed Central

Yomano, L P; Scopes, R K; Ingram, L O

1993-01-01

Phosphoglycerate mutase is an essential glycolytic enzyme for Zymomonas mobilis, catalyzing the reversible interconversion of 3-phosphoglycerate and 2-phosphoglycerate. The pgm gene encoding this enzyme was cloned on a 5.2-kbp DNA fragment and expressed in Escherichia coli. Recombinants were identified by using antibodies directed against purified Z. mobilis phosphoglycerate mutase. The pgm gene contains a canonical ribosome-binding site, a biased pattern of codon usage, a long upstream untranslated region, and four promoters which share sequence homology. Interestingly, adhA and a D-specific 2-hydroxyacid dehydrogenase were found on the same DNA fragment and appear to form a cluster of genes which function in central metabolism. The translated sequence for Z. mobilis pgm was in full agreement with the 40 N-terminal amino acid residues determined by protein sequencing. The primary structure of the translated sequence is highly conserved (52 to 60% identity with other phosphoglycerate mutases) and also shares extensive homology with bisphosphoglycerate mutases (51 to 59% identity). Since Southern blots indicated the presence of only a single copy of pgm in the Z. mobilis chromosome, it is likely that the cloned pgm gene functions to provide both activities. Z. mobilis phosphoglycerate mutase is unusual in that it lacks the flexible tail and lysines at the carboxy terminus which are present in the enzyme isolated from all other organisms examined. Images PMID:8320209

Accounting for all sugars produced during integrated production of ethanol from lignocellulosic biomass

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schell, Daniel J.; Dowe, Nancy; Chapeaux, Alexandre

This study explored integrated conversion of corn stover to ethanol and highlights techniques for accurate yield calculations. Acid pretreated corn stover (PCS) produced in a pilot-scale reactor was enzymatically hydrolyzed and the resulting sugars were fermented to ethanol by the glucose–xylose fermenting bacteria, Zymomonas mobilis 8b. The calculations account for high solids operation and oligomeric sugars produced during pretreatment, enzymatic hydrolysis, and fermentation, which, if not accounted for, leads to overestimating ethanol yields. The calculations are illustrated for enzymatic hydrolysis and fermentation of PCS at 17.5% and 20.0% total solids achieving 80.1% and 77.9% conversion of cellulose and xylan tomore » ethanol and ethanol titers of 63 g/L and 69 g/L, respectively. In the future, these techniques, including the TEA results, will be applied to fully integrated pilot-scale runs.« less

Accounting for all sugars produced during integrated production of ethanol from lignocellulosic biomass

DOE PAGES

Schell, Daniel J.; Dowe, Nancy; Chapeaux, Alexandre; ...

2016-01-19

This study explored integrated conversion of corn stover to ethanol and highlights techniques for accurate yield calculations. Acid pretreated corn stover (PCS) produced in a pilot-scale reactor was enzymatically hydrolyzed and the resulting sugars were fermented to ethanol by the glucose–xylose fermenting bacteria, Zymomonas mobilis 8b. The calculations account for high solids operation and oligomeric sugars produced during pretreatment, enzymatic hydrolysis, and fermentation, which, if not accounted for, leads to overestimating ethanol yields. The calculations are illustrated for enzymatic hydrolysis and fermentation of PCS at 17.5% and 20.0% total solids achieving 80.1% and 77.9% conversion of cellulose and xylan tomore » ethanol and ethanol titers of 63 g/L and 69 g/L, respectively. In the future, these techniques, including the TEA results, will be applied to fully integrated pilot-scale runs.« less

Sequence and genetic organization of a Zymomonas mobilis gene cluster that encodes several enzymes of glucose metabolism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barnell, W.O.; Kyung Cheol Yi; Conway, T.

1990-12-01

The Zymomonas mobilis genes that encode glucose-6-phosphate dehydrogenase (zwf), 6-phosphogluconate dehydratase (edd), and glucokinase (glk) were cloned independently by genetic complementation of specific defects in Escherichia coli metabolism. The identify of these cloned genes was confirmed by various biochemical means. Nucleotide sequence analysis established that these three genes are clustered on the genome and revealed an additional open reading frame in this region that has significant amino acid identity to the E.coli xylose-proton symporter and the human glucose transporter. On the basis of this evidence and structural analysis of the deduced primary amino acid sequence, this gene is believed tomore » encode the Z. mobilis glucose-facilitated diffusion protein, glf. The four genes in the 6-kb cluster are organized in the order glf, zwf, edd, glk. The glf and zwf genes are separated by 146 bp. The zwf and edd genes overlap by 8 bp, and their expression may be translationally coupled. The edd and glk genes are separated by 203 bp. The glk gene is followed by tandem transcriptional terminators. The four genes appear to be organized in an operon. Such an arrangement of the genes that govern glucose uptake and the first three steps of the Entner-Doudoroff glycolytic pathway provides the organism with a mechanism for carefully regulating the levels of the enzymes that control carbon flux into the pathway.« less

Very high gravity ethanol and fatty acid production of Zymomonas mobilis without amino acid and vitamin.

PubMed

Wang, Haoyong; Cao, Shangzhi; Wang, William Tianshuo; Wang, Kaven Tianyv; Jia, Xianhui

2016-06-01

Very high gravity (VHG) fermentation is the mainstream technology in ethanol industry, which requires the strains be resistant to multiple stresses such as high glucose concentration, high ethanol concentration, high temperature and harsh acidic conditions. To our knowledge, it was not reported previously that any ethanol-producing microbe showed a high performance in VHG fermentations without amino acid and vitamin. Here we demonstrate the engineering of a xylose utilizing recombinant Zymomonas mobilis for VHG ethanol fermentations. The recombinant strain can produce ethanol up to 136 g/L without amino acid and vitamin with a theoretical yield of 90 %, which is significantly superior to that produced by all the reported ethanol-producing strains. The intracellular fatty acids of the bacterial were about 16 % of the bacterial dry biomass, with the ratio of ethanol:fatty acids was about 273:1 (g/g). The recombinant strain was achieved by a multivariate-modular strategy tackles with the multiple stresses which are closely linked to the ethanol productivity of Z. mobilis. The over-expression of metB/yfdZ operon enabled the growth of the recombinant Z. mobilis in a chemically defined medium without amino acid and vitamin; and the fatty acids overproduction significantly increased ethanol tolerance and ethanol production. The coupled production of ethanol with fatty acids of the Z. mobilis without amino acid and vitamin under VHG fermentation conditions may permit a significant reduction of the production cost of ethanol and microbial fatty acids.

Fermentation of Soybean Meal Hydrolyzates with Saccharomyces cerevisiae and Zymomonas mobilis for Ethanol Production.

PubMed

Luján-Rhenals, Deivis E; Morawicki, Rubén O; Gbur, Edward E; Ricke, Steven C

2015-07-01

Most of the ethanol currently produced by fermentation is derived from sugar cane, corn, or beets. However, it makes good ecological and economic sense to use the carbohydrates contained in by-products and coproducts of the food processing industry for ethanol production. Soybean meal, a co-product of the production of soybean oil, has a relatively high carbohydrate content that could be a reasonable substrate for ethanol production after fermentable sugars are released via hydrolysis. In this research, the capability of Saccharomyces cerevisiae NRRL Y-2233 and Zymomonas mobilis subsp. mobilis NRRL B-4286 to produce ethanol was evaluated using soybean meal hydrolyzates as substrates for the fermentation. These substrates were produced from the dilute-acid hydrolysis of soybean meal at 135 °C for 45 min with 0, 0.5%, 1.25%, and 2% H2 SO4 and at 120 °C for 30 min with 1.25% H2 SO4 . Kinetic parameters of the fermentation were estimated using the logistic model. Ethanol production using S. cerevisiae was highest with the substrates obtained at 135 °C, 45 min, and 0.5% H2 SO4 and fermented for 8 h, 8 g/L (4 g ethanol/100 g fresh SBM), while Z. mobilis reached its maximum ethanol production, 9.2 g/L (4.6 g ethanol/100 g fresh SBM) in the first 20 h of fermentation with the same hydrolyzate. © 2015 Institute of Food Technologists®

Effect of acetic acid on ethanol production by Zymomonas mobilis mutant strains through continuous adaptation.

PubMed

Liu, Yu-Fan; Hsieh, Chia-Wen; Chang, Yao-Sheng; Wung, Being-Sun

2017-08-01

Acetic acid is a predominant by-product of lignocellulosic biofuel process, which inhibits microbial biocatalysts. Development of bacterial strains that are tolerant to acetic acid is challenging due to poor understanding of the underlying molecular mechanisms. In this study, we generated and characterized two acetic acid-tolerant strains of Zymomonas mobilis using N-methyl-N'-nitro-N-nitrosoguanidine (NTG)-acetate adaptive breeding. Two mutants, ZMA-142 and ZMA-167, were obtained, showing a significant growth rate at a concentration of 244 mM sodium acetate, while the growth of Z. mobilis ATCC 31823 were completely inhibited in presence of 195 mM sodium acetate. Our data showed that acetate-tolerance of ZMA-167 was attributed to a co-transcription of nhaA from ZMO0117, whereas the co-transcription was absent in ATCC 31823 and ZMA-142. Moreover, ZMA-142 and ZMA-167 exhibited a converstion rate (practical ethanol yield to theorical ethanol yield) of 90.16% and 86% at 195 mM acetate-pH 5 stress condition, respectively. We showed that acid adaptation of ZMA-142 and ZMA-167 to 146 mM acetate increased ZMA-142 and ZMA-167 resulted in an increase in ethanol yield by 32.21% and 21.16% under 195 mM acetate-pH 5 stress condition, respectively. The results indicate the acetate-adaptive seed culture of acetate-tolerant strains, ZMA-142 and ZMA-167, could enhance the ethanol production during fermentation.

Structure of the Zymomonas mobilis respiratory chain: oxygen affinity of electron transport and the role of cytochrome c peroxidase.

PubMed

Balodite, Elina; Strazdina, Inese; Galinina, Nina; McLean, Samantha; Rutkis, Reinis; Poole, Robert K; Kalnenieks, Uldis

2014-09-01

The genome of the ethanol-producing bacterium Zymomonas mobilis encodes a bd-type terminal oxidase, cytochrome bc1 complex and several c-type cytochromes, yet lacks sequences homologous to any of the known bacterial cytochrome c oxidase genes. Recently, it was suggested that a putative respiratory cytochrome c peroxidase, receiving electrons from the cytochrome bc1 complex via cytochrome c552, might function as a peroxidase and/or an alternative oxidase. The present study was designed to test this hypothesis, by construction of a cytochrome c peroxidase mutant (Zm6-perC), and comparison of its properties with those of a mutant defective in the cytochrome b subunit of the bc1 complex (Zm6-cytB). Disruption of the cytochrome c peroxidase gene (ZZ60192) caused a decrease of the membrane NADH peroxidase activity, impaired the resistance of growing culture to exogenous hydrogen peroxide and hampered aerobic growth. However, this mutation did not affect the activity or oxygen affinity of the respiratory chain, or the kinetics of cytochrome d reduction. Furthermore, the peroxide resistance and membrane NADH peroxidase activity of strain Zm6-cytB had not decreased, but both the oxygen affinity of electron transport and the kinetics of cytochrome d reduction were affected. It is therefore concluded that the cytochrome c peroxidase does not terminate the cytochrome bc1 branch of Z. mobilis, and that it is functioning as a quinol peroxidase. © 2014 The Authors.

Complete genome sequence and the expression pattern of plasmids of the model ethanologen Zymomonas mobilis ZM4 and its xylose-utilizing derivatives 8b and 2032.

PubMed

Yang, Shihui; Vera, Jessica M; Grass, Jeff; Savvakis, Giannis; Moskvin, Oleg V; Yang, Yongfu; McIlwain, Sean J; Lyu, Yucai; Zinonos, Irene; Hebert, Alexander S; Coon, Joshua J; Bates, Donna M; Sato, Trey K; Brown, Steven D; Himmel, Michael E; Zhang, Min; Landick, Robert; Pappas, Katherine M; Zhang, Yaoping

2018-01-01

Zymomonas mobilis is a natural ethanologen being developed and deployed as an industrial biofuel producer. To date, eight Z. mobilis strains have been completely sequenced and found to contain 2-8 native plasmids. However, systematic verification of predicted Z. mobilis plasmid genes and their contribution to cell fitness has not been hitherto addressed. Moreover, the precise number and identities of plasmids in Z. mobilis model strain ZM4 have been unclear. The lack of functional information about plasmid genes in ZM4 impedes ongoing studies for this model biofuel-producing strain. In this study, we determined the complete chromosome and plasmid sequences of ZM4 and its engineered xylose-utilizing derivatives 2032 and 8b. Compared to previously published and revised ZM4 chromosome sequences, the ZM4 chromosome sequence reported here contains 65 nucleotide sequence variations as well as a 2400-bp insertion. Four plasmids were identified in all three strains, with 150 plasmid genes predicted in strain ZM4 and 2032, and 153 plasmid genes predicted in strain 8b due to the insertion of heterologous DNA for expanded substrate utilization. Plasmid genes were then annotated using Blast2GO, InterProScan, and systems biology data analyses, and most genes were found to have apparent orthologs in other organisms or identifiable conserved domains. To verify plasmid gene prediction, RNA-Seq was used to map transcripts and also compare relative gene expression under various growth conditions, including anaerobic and aerobic conditions, or growth in different concentrations of biomass hydrolysates. Overall, plasmid genes were more responsive to varying hydrolysate concentrations than to oxygen availability. Additionally, our results indicated that although all plasmids were present in low copy number (about 1-2 per cell), the copy number of some plasmids varied under specific growth conditions or due to heterologous gene insertion. The complete genome of ZM4 and two xylose-utilizing derivatives is reported in this study, with an emphasis on identifying and characterizing plasmid genes. Plasmid gene annotation, validation, expression levels at growth conditions of interest, and contribution to host fitness are reported for the first time.

Bioethanol Production From Banana Stem By Using Simultaneous Saccharification and Fermentation (SSF)

NASA Astrophysics Data System (ADS)

Kusmiyati; Mustofa, A.; Jumarmi

2018-05-01

The rapid growth and development of industries in the world result in a greater energy needs. Some studies show that ethanol can be used as an alternative energy. However, bioethanol production from food raw materials such as sugar and starch has drawback that cause the food crisis. This aim of this study was to convert banana stem into bioethanol. Banana stem contained of 44.6% cellulose, 36.0% hemicellulose and 19.4% lignin. After banana stems were pretreated with acid (H2SO4) and alkaline (NaOH) at a concentration of 2% w/v at 121 °C for 30 minutes, then subsequently the simultaneous saccharification and fermentation (SSF) were carried out by using mixed cultures of Aspergillus niger, Trichoderma reesei and Zymomonas mobilis at various enzymes ratios of (1:1:1), (1:2:1), (1:2:2), (1:1:2) and various pH (4, 5 and 6) with SSF time for 144 hours and temperature of 30°C. The results show that acid pretreatment showed better results than the alkali pretreatment. After acid pretreatment and alkali pretreatment, lignin content of pretreted banana stem reduced to 15.92% and 16.34%, respectively, cellulose increased to 52.11% and 50.6% respectively, hemicellulose reduced to 28.45% and 28.83%, respectively The SSF showed that pH 5 gave the highest bioethanol. The highest concentration of bioethanol (8.51 g/L) was achieved at the SSF process at pH 5 with a ratio Aspergillus niger, Trichoderma reesei and Zymomonas mobilis enzymes of (1:1:2).

Single-species microbial biofilm screening for industrial applications.

PubMed

Li, Xuan Zhong; Hauer, Bernhard; Rosche, Bettina

2007-10-01

While natural microbial biofilms often consist of multiple species, single-species biofilms are of great interest to biotechnology. The current study evaluates biofilm formation for common industrial and laboratory microorganisms. A total of 68 species of biosafety level one bacteria and yeasts from over 40 different genera and five phyla were screened by growing them in microtiter plates and estimating attached biomass by crystal violet staining. Most organisms showed biofilm formation on surfaces of polystyrene within 24 h. By changing a few simple conditions such as substratum characteristics, inoculum and nutrient availability, 66 strains (97%) demonstrated biofilm formation under at least one of the experimental conditions and over half of these strains were classified as strong biofilm formers, potentially suitable as catalysts in biofilm applications. Many non-motile bacteria were also strong biofilm formers. Biofilm morphologies were visualized for selected strains. A model organism, Zymomonas mobilis, easily established itself as a biofilm on various reactor packing materials, including stainless steel.

Conceptual design of cost-effective and environmentally-friendly configurations for fuel ethanol production from sugarcane by knowledge-based process synthesis.

PubMed

Sánchez, Óscar J; Cardona, Carlos A

2012-01-01

In this work, the hierarchical decomposition methodology was used to conceptually design the production of fuel ethanol from sugarcane. The decomposition of the process into six levels of analysis was carried out. Several options of technological configurations were assessed in each level considering economic and environmental criteria. The most promising alternatives were chosen rejecting the ones with a least favorable performance. Aspen Plus was employed for simulation of each one of the technological configurations studied. Aspen Icarus was used for economic evaluation of each configuration, and WAR algorithm was utilized for calculation of the environmental criterion. The results obtained showed that the most suitable synthesized flowsheet involves the continuous cultivation of Zymomonas mobilis with cane juice as substrate and including cell recycling and the ethanol dehydration by molecular sieves. The proposed strategy demonstrated to be a powerful tool for conceptual design of biotechnological processes considering both techno-economic and environmental indicators. Copyright © 2011 Elsevier Ltd. All rights reserved.

Similarity of Escherichia coli propanediol oxidoreductase (fucO product) and an unusual alcohol dehydrogenase from Zymomonas mobilis and Saccharomyces cerevisiae

DOE Office of Scientific and Technical Information (OSTI.GOV)

Conway, T.; Ingram, L.O.

1989-07-01

The gene that encodes 1,2-propanediol oxidoreductase (fucO) from Escherichia coli was sequenced. The reading frame specified a protein of 383 amino acids (including the N-terminal methionine), with an aggregate molecular weight of 40,642. The induction of fucO transcription, which occurred in the presence of fucose, was confirmed by Northern blot analysis. In E. coli, the primary fucO transcript was approximately 2.1 kilobases in length. The 5{prime} end of the transcript began more than 0.7 kilobase upstream of the fucO start codon within or beyond the fucA gene. Propanediol oxidoreductase exhibited 41.7% identity with the iron-containing alcohol dehydrogenase II from Zymomonasmore » mobilis and 39.5% identity with ADH4 from Saccharomyces cerevisiae. These three proteins did not share homology with either short-chain or long-chain zinc-containing alcohol dehydrogenase enzymes. We propose that these three unusual alcohol dehydrogenases define a new family of enzymes.« less

De novo Biosynthesis of Biodiesel by Escherichia coli in Optimized Fed-Batch Cultivation

PubMed Central

Cai, Ke; Tan, Xiaoming; Lu, Xuefeng

2011-01-01

Biodiesel is a renewable alternative to petroleum diesel fuel that can contribute to carbon dioxide emission reduction and energy supply. Biodiesel is composed of fatty acid alkyl esters, including fatty acid methyl esters (FAMEs) and fatty acid ethyl esters (FAEEs), and is currently produced through the transesterification reaction of methanol (or ethanol) and triacylglycerols (TAGs). TAGs are mainly obtained from oilseed plants and microalgae. A sustainable supply of TAGs is a major bottleneck for current biodiesel production. Here we report the de novo biosynthesis of FAEEs from glucose, which can be derived from lignocellulosic biomass, in genetically engineered Escherichia coli by introduction of the ethanol-producing pathway from Zymomonas mobilis, genetic manipulation to increase the pool of fatty acyl-CoA, and heterologous expression of acyl-coenzyme A: diacylglycerol acyltransferase from Acinetobacter baylyi. An optimized fed-batch microbial fermentation of the modified E. coli strain yielded a titer of 922 mg L−1 FAEEs that consisted primarily of ethyl palmitate, -oleate, -myristate and -palmitoleate. PMID:21629774

From lin-benzoguanines to lin-benzohypoxanthines as ligands for Zymomonas mobilis tRNA-guanine transglycosylase: replacement of protein-ligand hydrogen bonding by importing water clusters.

PubMed

Barandun, Luzi Jakob; Immekus, Florian; Kohler, Philipp C; Tonazzi, Sandro; Wagner, Björn; Wendelspiess, Severin; Ritschel, Tina; Heine, Andreas; Kansy, Manfred; Klebe, Gerhard; Diederich, François

2012-07-23

The foodborne illness shigellosis is caused by Shigella bacteria that secrete the highly cytotoxic Shiga toxin, which is also formed by the closely related enterohemorrhagic Escherichia coli (EHEC). It has been shown that tRNA-guanine transglycosylase (TGT) is essential for the pathogenicity of Shigella flexneri. Herein, the molecular recognition properties of a guanine binding pocket in Zymomonas mobilis TGT are investigated with a series of lin-benzohypoxanthine- and lin-benzoguanine-based inhibitors that bear substituents to occupy either the ribose-33 or the ribose-34 pocket. The three inhibitor scaffolds differ by the substituent at C(6) being H, NH(2), or NH-alkyl. These differences lead to major changes in the inhibition constants, pK(a) values, and binding modes. Compared to the lin-benzoguanines, with an exocyclic NH(2) at C(6), the lin-benzohypoxanthines without an exocyclic NH(2) group have a weaker affinity as several ionic protein-ligand hydrogen bonds are lost. X-ray cocrystal structure analysis reveals that a new water cluster is imported into the space vacated by the lacking NH(2) group and by a conformational shift of the side chain of catalytic Asp102. In the presence of an N-alkyl group at C(6) in lin-benzoguanine ligands, this water cluster is largely maintained but replacement of one of the water molecules in the cluster leads to a substantial loss in binding affinity. This study provides new insight into the role of water clusters at enzyme active sites and their challenging substitution by ligand parts, a topic of general interest in contemporary structure-based drug design. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Systems Biology Analysis of Zymomonas mobilis ZM4 Ethanol Stress Responses

PubMed Central

Yang, Shihui; Pan, Chongle; Tschaplinski, Timothy J.; Hurst, Gregory B.; Engle, Nancy L.; Zhou, Wen; Dam, PhuongAn; Xu, Ying; Rodriguez, Miguel; Dice, Lezlee; Johnson, Courtney M.; Davison, Brian H.; Brown, Steven D.

2013-01-01

Background Zymomonas mobilis ZM4 is a capable ethanologenic bacterium with high ethanol productivity and ethanol tolerance. Previous studies indicated that several stress-related proteins and changes in the ZM4 membrane lipid composition may contribute to ethanol tolerance. However, the molecular mechanisms of its ethanol stress response have not been elucidated fully. Methodology/Principal Findings In this study, ethanol stress responses were investigated using systems biology approaches. Medium supplementation with an initial 47 g/L (6% v/v) ethanol reduced Z. mobilis ZM4 glucose consumption, growth rate and ethanol productivity compared to that of untreated controls. A proteomic analysis of early exponential growth identified about one thousand proteins, or approximately 55% of the predicted ZM4 proteome. Proteins related to metabolism and stress response such as chaperones and key regulators were more abundant in the early ethanol stress condition. Transcriptomic studies indicated that the response of ZM4 to ethanol is dynamic, complex and involves many genes from all the different functional categories. Most down-regulated genes were related to translation and ribosome biogenesis, while the ethanol-upregulated genes were mostly related to cellular processes and metabolism. Transcriptomic data were used to update Z. mobilis ZM4 operon models. Furthermore, correlations among the transcriptomic, proteomic and metabolic data were examined. Among significantly expressed genes or proteins, we observe higher correlation coefficients when fold-change values are higher. Conclusions Our study has provided insights into the responses of Z. mobilis to ethanol stress through an integrated “omics” approach for the first time. This systems biology study elucidated key Z. mobilis ZM4 metabolites, genes and proteins that form the foundation of its distinctive physiology and its multifaceted response to ethanol stress. PMID:23874800

Adaptive laboratory evolution of ethanologenic Zymomonas mobilis strain tolerant to furfural and acetic acid inhibitors.

PubMed

Shui, Zong-Xia; Qin, Han; Wu, Bo; Ruan, Zhi-yong; Wang, Lu-shang; Tan, Fu-Rong; Wang, Jing-Li; Tang, Xiao-Yu; Dai, Li-Chun; Hu, Guo-Quan; He, Ming-Xiong

2015-07-01

Furfural and acetic acid from lignocellulosic hydrolysates are the prevalent inhibitors to Zymomonas mobilis during cellulosic ethanol production. Developing a strain tolerant to furfural or acetic acid inhibitors is difficul by using rational engineering strategies due to poor understanding of their underlying molecular mechanisms. In this study, strategy of adaptive laboratory evolution (ALE) was used for development of a furfural and acetic acid-tolerant strain. After three round evolution, four evolved mutants (ZMA7-2, ZMA7-3, ZMF3-2, and ZMF3-3) that showed higher growth capacity were successfully obtained via ALE method. Based on the results of profiling of cell growth, glucose utilization, ethanol yield, and activity of key enzymes, two desired strains, ZMA7-2 and ZMF3-3, were achieved, which showed higher tolerance under 7 g/l acetic acid and 3 g/l furfural stress condition. Especially, it is the first report of Z. mobilis strain that could tolerate higher furfural. The best strain, Z. mobilis ZMF3-3, has showed 94.84% theoretical ethanol yield under 3-g/l furfural stress condition, and the theoretical ethanol yield of ZM4 is only 9.89%. Our study also demonstrated that ALE method might also be used as a powerful metabolic engineering tool for metabolic engineering in Z. mobilis. Furthermore, the two best strains could be used as novel host for further metabolic engineering in cellulosic ethanol or future biorefinery. Importantly, the two strains may also be used as novel-tolerant model organisms for the genetic mechanism on the "omics" level, which will provide some useful information for inverse metabolic engineering.

Use of a Tn5-based transposon system to create a cost-effective Zymomonas mobilis for ethanol production from lignocelluloses

PubMed Central

2013-01-01

Background Current methods of ethanol production from lignocelluloses generate a mixture of sugars, primarily glucose and xylose; the fermentation cells are always exposed to stresses like high temperature and low nutritional conditions that affect their growth and productivity. Stress-tolerant strains capable of using both glucose and xylose to produce ethanol with high yield are highly desirable. Results A recombinant Zymomonas mobilis (Z. mobilis) designated as HYMX was constructed by integrating seven genes (Pfu-sHSP, yfdZ, metB, xylA, xylB, tktA and talB) into the genome of Z. mobilis CP4 (CP4) via Tn5 transposon in the present study. The small heat shock protein gene (Pfu-sHSP) from Pyrococcus furious (P. furious) was used to increase the heat-tolerance, the yfdZ and metB genes from E. coli were used to decrease the nutritional requirement. To overcome the bottleneck of CP4 being unable to use pentose, xylose catabolic genes (xylA, xylB, tktA and talB) from E. coli were integrated into CP4 also for construction of the xylose utilizing metabolic pathway. Conclusions The genomic integration confers on Z. mobilis the ability to grow in medium containing xylose as the only carbon source, and to grow in simple chemical defined medium without addition of amino acid. The HYMX demonstrated not only the high tolerance to unfavorable stresses like high temperature and low nutrient, but also the capability of converting both glucose and xylose to ethanol with high yield at high temperature. What’s more, these genetic characteristics were stable up to 100 generations on nonselective medium. Although significant improvements were achieved, yeast extract is needed for ethanol production. PMID:23635356

Novel reaction for new fuels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clyde, R.A.

Independent investigators have found that sugar can be fermented to alcohol for gasohol in 15 minutes by immobilizing organisms such as Zymomonas mobilis on rotating fibers. Half a pound of Celite has the surface area of a football field and it can be entrapped in the fibers to hold many cells. Many others take several hours. In another design, methanol can be dissociated to CO and H{sub 2} and 30% more energy obtained because waste heat is utilized. When one mol goes to three there is an expansion, and this is provided for. Both these designs result in clean fuelsmore » and are covered by U.S. patents.« less

Complete genome sequence and the expression pattern of plasmids of the model ethanologen Zymomonas mobilis ZM4 and its xylose-utilizing derivatives 8b and 2032

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Shihui; Vera, Jessica M.; Grass, Jeff

Zymomonas mobilis is a natural ethanologen being developed and deployed as an industrial biofuel producer. To date, eight Z. mobilis strains have been completely sequenced and found to contain 2-8 native plasmids. However, systematic verification of predicted Z. mobilis plasmid genes and their contribution to cell fitness has not been hitherto addressed. Moreover, the precise number and identities of plasmids in Z. mobilis model strain ZM4 have been unclear. The lack of functional information about plasmid genes in ZM4 impedes ongoing studies for this model biofuel-producing strain. In this study, we determined the complete chromosome and plasmid sequences of ZM4more » and its engineered xylose-utilizing derivatives 2032 and 8b. Compared to previously published and revised ZM4 chromosome sequences, the ZM4 chromosome sequence reported here contains 65 nucleotide sequence variations as well as a 2400-bp insertion. Four plasmids were identified in all three strains, with 150 plasmid genes predicted in strain ZM4 and 2032, and 153 plasmid genes predicted in strain 8b due to the insertion of heterologous DNA for expanded substrate utilization. Plasmid genes were then annotated using Blast2GO, InterProScan, and systems biology data analyses, and most genes were found to have apparent orthologs in other organisms or identifiable conserved domains. To verify plasmid gene prediction, RNA-Seq was used to map transcripts and also compare relative gene expression under various growth conditions, including anaerobic and aerobic conditions, or growth in different concentrations of biomass hydrolysates. Overall, plasmid genes were more responsive to varying hydrolysate concentrations than to oxygen availability. Additionally, our results indicated that although all plasmids were present in low copy number (about 1-2 per cell), the copy number of some plasmids varied under specific growth conditions or due to heterologous gene insertion. The complete genome of ZM4 and two xylose-utilizing derivatives is reported in this study, with an emphasis on identifying and characterizing plasmid genes. Furthermore, plasmid gene annotation, validation, expression levels at growth conditions of interest, and contribution to host fitness are reported for the first time.« less

Complete genome sequence and the expression pattern of plasmids of the model ethanologen Zymomonas mobilis ZM4 and its xylose-utilizing derivatives 8b and 2032

DOE PAGES

Yang, Shihui; Vera, Jessica M.; Grass, Jeff; ...

2018-05-02

Zymomonas mobilis is a natural ethanologen being developed and deployed as an industrial biofuel producer. To date, eight Z. mobilis strains have been completely sequenced and found to contain 2-8 native plasmids. However, systematic verification of predicted Z. mobilis plasmid genes and their contribution to cell fitness has not been hitherto addressed. Moreover, the precise number and identities of plasmids in Z. mobilis model strain ZM4 have been unclear. The lack of functional information about plasmid genes in ZM4 impedes ongoing studies for this model biofuel-producing strain. In this study, we determined the complete chromosome and plasmid sequences of ZM4more » and its engineered xylose-utilizing derivatives 2032 and 8b. Compared to previously published and revised ZM4 chromosome sequences, the ZM4 chromosome sequence reported here contains 65 nucleotide sequence variations as well as a 2400-bp insertion. Four plasmids were identified in all three strains, with 150 plasmid genes predicted in strain ZM4 and 2032, and 153 plasmid genes predicted in strain 8b due to the insertion of heterologous DNA for expanded substrate utilization. Plasmid genes were then annotated using Blast2GO, InterProScan, and systems biology data analyses, and most genes were found to have apparent orthologs in other organisms or identifiable conserved domains. To verify plasmid gene prediction, RNA-Seq was used to map transcripts and also compare relative gene expression under various growth conditions, including anaerobic and aerobic conditions, or growth in different concentrations of biomass hydrolysates. Overall, plasmid genes were more responsive to varying hydrolysate concentrations than to oxygen availability. Additionally, our results indicated that although all plasmids were present in low copy number (about 1-2 per cell), the copy number of some plasmids varied under specific growth conditions or due to heterologous gene insertion. The complete genome of ZM4 and two xylose-utilizing derivatives is reported in this study, with an emphasis on identifying and characterizing plasmid genes. Furthermore, plasmid gene annotation, validation, expression levels at growth conditions of interest, and contribution to host fitness are reported for the first time.« less

Importance of stability study of continuous systems for ethanol production.

PubMed

Paz Astudillo, Isabel Cristina; Cardona Alzate, Carlos Ariel

2011-01-10

Fuel ethanol industry presents different problems during bioreactors operation. One of them is the unexpected variation in the output ethanol concentration from the bioreactor or a drastic fall in the productivity. In this paper, a compilation of concepts and relevant results of several experimental and theoretical studies about dynamic behavior of fermentation systems for bioethanol production with Saccharomyces cerevisiae and Zymomonas mobilis is done with the purpose of understanding the stability phenomena that could affect the productivity of industries producing fuel ethanol. It is shown that the design of high scale biochemical processes for fuel ethanol production must be done based on stability studies. © 2010 Elsevier B.V. All rights reserved.

Optical mapping and sequencing of the Escherichia coli KO11 genome reveal extensive chromosomal rearrangements, and multiple tandem copies of the Zymomonas mobilis pdc and adhB genes.

PubMed

Turner, Peter C; Yomano, Lorraine P; Jarboe, Laura R; York, Sean W; Baggett, Christy L; Moritz, Brélan E; Zentz, Emily B; Shanmugam, K T; Ingram, Lonnie O

2012-04-01

Escherichia coli KO11 (ATCC 55124) was engineered in 1990 to produce ethanol by chromosomal insertion of the Zymomonas mobilis pdc and adhB genes into E. coli W (ATCC 9637). KO11FL, our current laboratory version of KO11, and its parent E. coli W were sequenced, and contigs assembled into genomic sequences using optical NcoI restriction maps as templates. E. coli W contained plasmids pRK1 (102.5 kb) and pRK2 (5.4 kb), but KO11FL only contained pRK2. KO11FL optical maps made with AflII and with BamHI showed a tandem repeat region, consisting of at least 20 copies of a 10-kb unit. The repeat region was located at the insertion site for the pdc, adhB, and chloramphenicol-resistance genes. Sequence coverage of these genes was about 25-fold higher than average, consistent with amplification of the foreign genes that were inserted as circularized DNA. Selection for higher levels of chloramphenicol resistance originally produced strains with higher pdc and adhB expression, and hence improved fermentation performance, by increasing the gene copy number. Sequence data for an earlier version of KO11, ATCC 55124, indicated that multiple copies of pdc adhB were present. Comparison of the W and KO11FL genomes showed large inversions and deletions in KO11FL, mostly enabled by IS10, which is absent from W but present at 30 sites in KO11FL. The early KO11 strain ATCC 55124 had no rearrangements, contained only one IS10, and lacked most accumulated single nucleotide polymorphisms (SNPs) present in KO11FL. Despite rearrangements and SNPs in KO11FL, fermentation performance was equal to that of ATCC 55124.

Comparing the fermentation performance of Escherichia coli KO11, Saccharomyces cerevisiae 424A(LNH-ST) and Zymomonas mobilis AX101 for cellulosic ethanol production

PubMed Central

2010-01-01

Background Fermentations using Escherichia coli KO11, Saccharomyces cerevisiae 424A(LNH-ST), and Zymomonas mobilis AX101 are compared side-by-side on corn steep liquor (CSL) media and the water extract and enzymatic hydrolysate from ammonia fiber expansion (AFEX)-pretreated corn stover. Results The three ethanologens are able produce ethanol from a CSL-supplemented co-fermentation at a metabolic yield, final concentration and rate greater than 0.42 g/g consumed sugars, 40 g/L and 0.7 g/L/h (0-48 h), respectively. Xylose-only fermentation of the tested ethanologenic bacteria are five to eight times faster than 424A(LNH-ST) in the CSL fermentation. All tested strains grow and co-ferment sugars at 15% w/v solids loading equivalent of ammonia fiber explosion (AFEX)-pretreated corn stover water extract. However, both KO11 and 424A(LNH-ST) exhibit higher growth robustness than AX101. In 18% w/w solids loading lignocellulosic hydrolysate from AFEX pretreatment, complete glucose fermentations can be achieved at a rate greater than 0.77 g/L/h. In contrast to results from fermentation in CSL, S. cerevisiae 424A(LNH-ST) consumed xylose at the greatest extent and rate in the hydrolysate compared to the bacteria tested. Conclusions Our results confirm that glucose fermentations among the tested strains are effective even at high solids loading (18% by weight). However, xylose consumption in the lignocellulosic hydrolysate is the major bottleneck affecting overall yield, titer or rate of the process. In comparison, Saccharomyces cerevisiae 424A(LNH-ST) is the most relevant strains for industrial production for its ability to ferment both glucose and xylose from undetoxified and unsupplemented hydrolysate from AFEX-pretreated corn stover at high yield. PMID:20507563

Inhibition of growth of Zymomonas mobilis by model compounds found in lignocellulosic hydrolysates

PubMed Central

2013-01-01

Background During the pretreatment of biomass feedstocks and subsequent conditioning prior to saccharification, many toxic compounds are produced or introduced which inhibit microbial growth and in many cases, production of ethanol. An understanding of the toxic effects of compounds found in hydrolysate is critical to improving sugar utilization and ethanol yields in the fermentation process. In this study, we established a useful tool for surveying hydrolysate toxicity by measuring growth rates in the presence of toxic compounds, and examined the effects of selected model inhibitors of aldehydes, organic and inorganic acids (along with various cations), and alcohols on growth of Zymomonas mobilis 8b (a ZM4 derivative) using glucose or xylose as the carbon source. Results Toxicity strongly correlated to hydrophobicity in Z. mobilis, which has been observed in Escherichia coli and Saccharomyces cerevisiae for aldehydes and with some exceptions, organic acids. We observed Z. mobilis 8b to be more tolerant to organic acids than previously reported, although the carbon source and growth conditions play a role in tolerance. Growth in xylose was profoundly inhibited by monocarboxylic organic acids compared to growth in glucose, whereas dicarboxylic acids demonstrated little or no effects on growth rate in either substrate. Furthermore, cations can be ranked in order of their toxicity, Ca++ > > Na+ > NH4+ > K+. HMF (5-hydroxymethylfurfural), furfural and acetate, which were observed to contribute to inhibition of Z. mobilis growth in dilute acid pretreated corn stover hydrolysate, do not interact in a synergistic manner in combination. We provide further evidence that Z. mobilis 8b is capable of converting the aldehydes furfural, vanillin, 4-hydroxybenzaldehyde and to some extent syringaldehyde to their alcohol forms (furfuryl, vanillyl, 4-hydroxybenzyl and syringyl alcohol) during fermentation. Conclusions Several key findings in this report provide a mechanism for predicting toxic contributions of inhibitory components of hydrolysate and provide guidance for potential process development, along with potential future strain improvement and tolerance strategies. PMID:23837621

Improving a recombinant Zymomonas mobilis strain 8b through continuous adaptation on dilute acid pretreated corn stover hydrolysate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohagheghi, Ali; Linger, Jeffrey G.; Yang, Shihui

Complete conversion of the major sugars of biomass including both the C 5 and C 6 sugars is critical for biofuel production processes. Several inhibitory compounds like acetate, hydroxymethylfurfural (HMF), and furfural are produced from the biomass pretreatment process leading to ‘hydrolysate toxicity,’ a major problem for microorganisms to achieve complete sugar utilization. Therefore, development of more robust microorganisms to utilize the sugars released from biomass under toxic environment is critical. In this study, we use continuous culture methodologies to evolve and adapt the ethanologenic bacterium Zymomonas mobilis to improve its ethanol productivity using corn stover hydrolysate. The results aremore » the following: A turbidostat was used to adapt the Z. mobilis strain 8b in the pretreated corn stover liquor. The adaptation was initiated using pure sugar (glucose and xylose) followed by feeding neutralized liquor at different dilution rates. Once the turbidostat reached 60% liquor content, the cells began washing out and the adaptation was stopped. Several ‘sub-strains’ were isolated, and one of them, SS3 (sub-strain 3), had 59% higher xylose utilization than the parent strain 8b when evaluated on 55% neutralized PCS (pretreated corn stover) liquor. Using saccharified PCS slurry generated by enzymatic hydrolysis from 25% solids loading, SS3 generated an ethanol yield of 75.5% compared to 64% for parent strain 8b. Furthermore, the total xylose utilization was 57.7% for SS3 versus 27.4% for strain 8b. To determine the underlying genotypes in these new sub-strains, we conducted genomic resequencing and identified numerous single-nucleotide mutations (SNPs) that had arisen in SS3. We further performed quantitative reverse transcription PCR (qRT-PCR) on genes potentially affected by these SNPs and identified significant down-regulation of two genes, ZMO0153 and ZMO0776, in SS3 suggesting potential genetic mechanisms behind SS3’s improved performance. In conclusion, we have adapted/evolved Z. mobilis strain 8b for enhanced tolerance to the toxic compounds present in corn stover hydrolysates. The adapted strain SS3 has higher xylose utilization rate and produce more ethanol than the parent strain. We have identified transcriptional changes which may be responsible for these phenotypes, providing foundations for future research directions in improving Z. mobilis as biocatalysts for the production of ethanol or other fuel precursors.« less

Improving a recombinant Zymomonas mobilis strain 8b through continuous adaptation on dilute acid pretreated corn stover hydrolysate

DOE PAGES

Mohagheghi, Ali; Linger, Jeffrey G.; Yang, Shihui; ...

2015-03-31

Complete conversion of the major sugars of biomass including both the C 5 and C 6 sugars is critical for biofuel production processes. Several inhibitory compounds like acetate, hydroxymethylfurfural (HMF), and furfural are produced from the biomass pretreatment process leading to ‘hydrolysate toxicity,’ a major problem for microorganisms to achieve complete sugar utilization. Therefore, development of more robust microorganisms to utilize the sugars released from biomass under toxic environment is critical. In this study, we use continuous culture methodologies to evolve and adapt the ethanologenic bacterium Zymomonas mobilis to improve its ethanol productivity using corn stover hydrolysate. The results aremore » the following: A turbidostat was used to adapt the Z. mobilis strain 8b in the pretreated corn stover liquor. The adaptation was initiated using pure sugar (glucose and xylose) followed by feeding neutralized liquor at different dilution rates. Once the turbidostat reached 60% liquor content, the cells began washing out and the adaptation was stopped. Several ‘sub-strains’ were isolated, and one of them, SS3 (sub-strain 3), had 59% higher xylose utilization than the parent strain 8b when evaluated on 55% neutralized PCS (pretreated corn stover) liquor. Using saccharified PCS slurry generated by enzymatic hydrolysis from 25% solids loading, SS3 generated an ethanol yield of 75.5% compared to 64% for parent strain 8b. Furthermore, the total xylose utilization was 57.7% for SS3 versus 27.4% for strain 8b. To determine the underlying genotypes in these new sub-strains, we conducted genomic resequencing and identified numerous single-nucleotide mutations (SNPs) that had arisen in SS3. We further performed quantitative reverse transcription PCR (qRT-PCR) on genes potentially affected by these SNPs and identified significant down-regulation of two genes, ZMO0153 and ZMO0776, in SS3 suggesting potential genetic mechanisms behind SS3’s improved performance. In conclusion, we have adapted/evolved Z. mobilis strain 8b for enhanced tolerance to the toxic compounds present in corn stover hydrolysates. The adapted strain SS3 has higher xylose utilization rate and produce more ethanol than the parent strain. We have identified transcriptional changes which may be responsible for these phenotypes, providing foundations for future research directions in improving Z. mobilis as biocatalysts for the production of ethanol or other fuel precursors.« less

Inhibition of microbial biofuel production in drought-stressed switchgrass hydrolysate

DOE PAGES

Ong, Rebecca Garlock; Higbee, Alan; Bottoms, Scott; ...

2016-11-08

Here, interannual variability in precipitation, particularly drought, can affect lignocellulosic crop biomass yields and composition, and is expected to increase biofuel yield variability. However, the effect of precipitation on downstream fermentation processes has never been directly characterized. In order to investigate the impact of interannual climate variability on biofuel production, corn stover and switchgrass were collected during 3 years with significantly different precipitation profiles, representing a major drought year (2012) and 2 years with average precipitation for the entire season (2010 and 2013). All feedstocks were AFEX (ammonia fiber expansion)-pretreated, enzymatically hydrolyzed, and the hydrolysates separately fermented using xylose-utilizing strainsmore » of Saccharomyces cerevisiae and Zymomonas mobilis. As a result, a chemical genomics approach was also used to evaluate the growth of yeast mutants in the hydrolysates.« less

Starch saccharification and fermentation of uncooked sweet potato roots for fuel ethanol production.

PubMed

Zhang, Peng; Chen, Caifa; Shen, Yanhu; Ding, Tielin; Ma, Daifu; Hua, Zichun; Sun, Dongxu

2013-01-01

An energy-saving ethanol fermentation technology was developed using uncooked fresh sweet potato as raw material. A mutant strain of Aspergillus niger isolated from mildewed sweet potato was used to produce abundant raw starch saccharification enzymes for treating uncooked sweet potato storage roots. The viscosity of the fermentation paste of uncooked sweet potato roots was lower than that of the cooked roots. The ethanol fermentation was carried out by Zymomonas mobilis, and 14.4 g of ethanol (87.2% of the theoretical yield) was produced from 100g of fresh sweet potato storage roots. Based on this method, an energy-saving, high efficient and environment-friendly technology can be developed for large-scale production of fuel ethanol from sweet potato roots. Copyright © 2012 Elsevier Ltd. All rights reserved.

Bio-based extraction and stabilization of anthocyanins.

PubMed

Roy, Anirban; Mukherjee, Rudra Palash; Howard, Luke; Beitle, Robert

2016-05-01

This work reports a novel method of recovering anthocyanin compounds from highly-pigmented grapes via a fermentation based approach. It was hypothesized that batch growth of Zymomonas mobilis on simple medium would produce both ethanol and enzymes/biomass-acting materials, the combination of which will provide a superior extraction when compared to simple alcohol extraction. To examine this hypothesis, Z. mobilis was fermented in a batch consisting of mashed Vitis vinifera and glucose, and the recovered anthocyanin pool was compared to that recovered via extraction with ethanol. Data indicated higher amounts of anthocyanins were recovered when compared to simple solvent addition. Additionally, the percent polymeric form of the anthocyanins could be manipulated by the level of aeration maintained in the fermentation. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:601-605, 2016. © 2016 American Institute of Chemical Engineers.

Pulque production from fermented agave sap as a dietary supplement in Prehispanic Mesoamerica.

PubMed

Correa-Ascencio, Marisol; Robertson, Ian G; Cabrera-Cortés, Oralia; Cabrera-Castro, Rubén; Evershed, Richard P

2014-09-30

Although in modern societies fermented beverages are associated with socializing, celebration, and ritual, in ancient times they were also importa`nt sources of essential nutrients and potable water. In Mesoamerica, pulque, an alcoholic beverage produced from the fermented sap of several species of maguey plants (Agavaceae; Fig. 1) is hypothesized to have been used as a dietary supplement and risk-buffering food in ancient Teotihuacan (150 B.C. to A.D. 650). Although direct archaeological evidence of pulque production is lacking, organic residue analysis of pottery vessels offers a new avenue of investigation. However, the chemical components of alcoholic beverages are water-soluble, greatly limiting their survival over archaeological timescales compared with hydrophobic lipids widely preserved in food residues. Hence, we apply a novel lipid biomarker approach that considers detection of bacteriohopanoids derived from the ethanol-producing bacterium Zymomonas mobilis for identifying pulque production/consumption in pottery vessels. Gas chromatography-mass spectrometry selected ion monitoring (m/z 191) of lipid extracts of >300 potsherds revealed characteristic bacteriohopanoid distributions in a subset of 14 potsherds. This hopanoid biomarker approach offers a new means of identifying commonly occurring bacterially fermented alcoholic beverages worldwide, including palm wine, beer, cider, perry, and other plant sap- or fruit-derived beverages [Swings J, De Ley J (1977) Bacteriol Rev 41(1):1-46].

A comparison of simple rheological parameters and simulation data for Zymomonas mobilis fermentation broths with high substrate loading in a 3-L bioreactor.

PubMed

Um, Byung-Hwan; Hanley, Thomas R

2008-03-01

Traditionally, as much as 80% or more of an ethanol fermentation broth is water that must be removed. This mixture is not only costly to separate but also produces a large aqueous stream that must then be disposed of or recycled. Integrative approaches to water reduction include increasing the biomass concentration during fermentation. In this paper, experimental results are presented for the rheological behavior of high-solids enzymatic cellulose hydrolysis and ethanol fermentation for biomass conversion using Solka Floc as the model feedstock. The experimental determination of the viscosity, shear stress, and shear rate relationships of the 10 to 20% slurry concentrations with constant enzyme concentrations are performed with a variable speed rotational viscometer (2.0 to 200 rpm) at 40 degrees C. The viscosities of enzymatic suspension observed were in range of 0.0418 to 0.0144, 0.233 to 0.0348, and 0.292 to 0.0447 Pa s for shear rates up to 100 reciprocal seconds at 10, 15, and 20% initial solids (w/v), respectively. Computational fluid dynamics analysis of bioreactor mixing demonstrates the change in bioreactor mixing with increasing biomass concentration. The portion-loading method is shown to be effective for processing high-solids slurries.

A Comparison of Simple Rheological Parameters and Simulation Data for Zymomonas mobilis Fermentation Broths with High Substrate Loading in a 3-L Bioreactor

NASA Astrophysics Data System (ADS)

Um, Byung-Hwan; Hanley, Thomas R.

Traditionally, as much as 80% or more of an ethanol fermentation broth is water that must be removed. This mixture is not only costly to separate but also produces a large aqueous stream that must then be disposed of or recycled. Integrative approaches to water reduction include increasing the biomass concentration during fermentation. In this paper, experimental results are presented for the rheological behavior of high-solids enzymatic cellulose hydrolysis and ethanol fermentation for biomass conversion using Solka Floc as the model feedstock. The experimental determination of the viscosity, shear stress, and shear rate relationships of the 10 to 20% slurry concentrations with constant enzyme concentrations are performed with a variable speed rotational viscometer (2.0 to 200 rpm) at 40 °C. The viscosities of enzymatic suspension observed were in range of 0.0418 to 0.0144, 0.233 to 0.0348, and 0.292 to 0.0447 Pa s for shear rates up to 100 reciprocal seconds at 10, 15, and 20% initial solids (w/v), respectively. Computational fluid dynamics analysis of bioreactor mixing demonstrates the change in bioreactor mixing with increasing biomass concentration. The portion-loading method is shown to be effective for processing highsolids slurries.

The state of autotrophic ethanol production in Cyanobacteria.

PubMed

Dexter, J; Armshaw, P; Sheahan, C; Pembroke, J T

2015-07-01

Ethanol production directly from CO2 , utilizing genetically engineered photosynthetic cyanobacteria as a biocatalyst, offers significant potential as a renewable and sustainable source of biofuel. Despite the current absence of a commercially successful production system, significant resources have been deployed to realize this goal. Utilizing the pyruvate decarboxylase from Zymomonas species, metabolically derived pyruvate can be converted to ethanol. This review of both peer-reviewed and patent literature focuses on the genetic modifications utilized for metabolic engineering and the resultant effect on ethanol yield. Gene dosage, induced expression and cassette optimizat-ion have been analyzed to optimize production, with production rates of 0·1-0·5 g L(-1) day(-1) being achieved. The current 'toolbox' of molecular manipulations and future directions focusing on applicability, addressing the primary challenges facing commercialization of cyanobacterial technologies are discussed. © 2015 The Society for Applied Microbiology.

Mathematical modeling of ethanol production in solid-state fermentation based on solid medium' dry weight variation.

PubMed

Mazaheri, Davood; Shojaosadati, Seyed Abbas; Zamir, Seyed Morteza; Mousavi, Seyyed Mohammad

2018-04-21

In this work, mathematical modeling of ethanol production in solid-state fermentation (SSF) has been done based on the variation in the dry weight of solid medium. This method was previously used for mathematical modeling of enzyme production; however, the model should be modified to predict the production of a volatile compound like ethanol. The experimental results of bioethanol production from the mixture of carob pods and wheat bran by Zymomonas mobilis in SSF were used for the model validation. Exponential and logistic kinetic models were used for modeling the growth of microorganism. In both cases, the model predictions matched well with the experimental results during the exponential growth phase, indicating the good ability of solid medium weight variation method for modeling a volatile product formation in solid-state fermentation. In addition, using logistic model, better predictions were obtained.

Semicontinuous production of ethanol from agricultural wastes by immobilised coculture in a two stage bioreactor.

PubMed

Dey, Sabita

2002-10-01

The seed testing laboratories of Maharashtra discard 10 tonnes of grains and oil seeds treated with pesticides per annum. These agricultural wastes could be converted to reducing sugar and ethanol in a two stage semicontinuous fluidised bed bioreactor containing immobilised, Bacillus sp. and Zymomonas mobilis in the 1st stage and Saccharomyces diastaticus and S. cerevisae in the 2nd stage. The optimum temperature and pH for fermentation in both the stages were 30 degrees C and 7.2 respectively. In this process 600 g (approximately 400 g starch) waste seeds could yield 402 g of reducing sugar in the 1st stage after 20 h and 205 g ethanol in the 2nd stage after 40 h incubation with a yield factor 0.51. Using these system 10 tonnes of agricultural wastes could be converted to 3.4 x 107 g of ethanol.

[Optimization of fuel ethanol production from kitchen waste by Plackett-Burman design].

PubMed

Ma, Hong-Zhi; Gong, Li-Juan; Wang, Qun-Hui; Zhang, Wen-Yu; Xu, Wen-Long

2008-05-01

Kitchen garbage was chosen to produce ethanol through simultaneous saccharification and fermentation (SSF) by Zymomonas mobilis. Plackett-Burman design was employed to screen affecting parameters during SSF process. The parameters were divided into two parts, enzymes and nutritions. None of the nutritions added showed significant effect during the experiment, which demonstrated that the kitchen garbage could meet the requirement of the microorganism without extra supplementation. Protease and glucoamylase were determined to be affecting factors for ethanol production. Single factor experiment showed that the optimum usage of these two enzymes were both 100 U/g and the corresponding maximum ethanol was determined to be 53 g/L. The ethanol yield could be as high as 44%. The utilization of kitchen garbage to produce ethanol could reduce threaten of waste as well as improve the protein content of the spent. This method could save the ethanol production cost and benefit for the recycle of kitchen garbage.

Technique of ethanol food grade production with batch distillation and dehydration using starch-based adsorbent

NASA Astrophysics Data System (ADS)

Widjaja, Tri; Altway, Ali; Ni'mah, Hikmatun; Tedji, Namira; Rofiqah, Umi

2015-12-01

Development and innovation of ethanol food grade production are becoming the reasearch priority to increase economy growth. Moreover, the government of Indonesia has established regulation for increasing the renewable energy as primary energy. Sorghum is cerealia plant that contains 11-16% sugar that is optimum for fermentation process, it is potential to be cultivated, especially at barren area in Indonesia. The purpose of this experiment is to learn about the effect of microorganisms in fermentation process. Fermentation process was carried out batchwise in bioreactor and used 150g/L initial sugar concentration. Microorganisms used in this experiment are Zymomonas mobilis mutation (A3), Saccharomyces cerevisiae and mixed of Pichia stipitis. The yield of ethanol can be obtained from this experiment. For ethanol purification result, distillation process from fermentation process has been done to search the best operation condition for efficiency energy consumption. The experiment for purification was divided into two parts, which are distillation with structured packing steel wool and adsorption (dehydration) sequencely. In distillation part, parameters evaluation (HETP and pressure drop) of distillation column that can be used for scale up are needed. The experiment was operated at pressure of 1 atm. The distillation stage was carried out at 85 °C and reflux ratio of 0.92 with variety porosities of 20%, 40%, and 60%. Then the adsorption process was done at 120°C and two types of adsorbent, which are starch - based adsorbent with ingredient of cassava and molecular sieve 3A, were used. The adsorption process was then continued to purify the ethanol from impurities by using activated carbon. This research shows that the batch fermentation process with Zymomonas mobilis A3 obtain higher % yield of ethanol of 40,92%. In addition to that, for purification process, the best operation condition is by using 40% of porosity of stuctured packing steel wool in distillation stage and starch-based adsorbent in adsorption stage, which can obtain ethanol content of 92,15% with acetic acid percentage of 0,001% and the rest is water. This result is qualified for ethanol food grade specification which is between 90 - 94 % of ethanol with maximum percentage of acetic acid is 0,003%, and passes in fusel oil and isopropyl alcohol test.

Fermentable metabolite of Zymomonas mobilis controls collagen reduction in photoaging skin by improving TGF-beta/Smad signaling suppression.

PubMed

Tanaka, Hiroshi; Yamaba, Hiroyuki; Kosugi, Nobuhiko; Mizutani, Hiroshi; Nakata, Satoru

2008-04-01

Solar ultraviolet (UV) irradiation causes damages on human skin and premature skin aging (photoaging). UV-induced reduction of type I collagen in dermis is widely considered primarily induction of wrinkled appearance of photoaging skin. Type I procollagen synthesis is reduced under UV irradiation by blocking transforming growth factor-beta (TGF-beta)/Smad signaling; more specifically, it is down-regulation of TGF-beta type II receptor (T beta RII). Therefore, preventing UV-induced loss of T beta RII results decreased type I collagen reduction in photoaging skin. Zymomonas mobilis is an alcohol fermentable, gram-negative facultative anaerobic bacterium whose effect on skin tissue is scarcely studied. We investigated the protective effects of fermentable metabolite of Z. mobilis (FM of Z. mobilis) against reduction of type I procollagen synthesis of UV-induced down-regulation of T beta RII in human dermal fibroblasts FM of Z. mobilis was obtained from lyophilization of bacterium culture supernatant. The levels of T beta RII and type I procollagen mRNA in human dermal fibroblasts were measured by quantitative real-time RT-PCR, and T beta RII protein levels were assayed by western blotting. T beta RII, type I procollagen, and type I collagen proteins in human dermal fibroblasts or hairless mouse skin were detected by immunostaining. FM of Z. mobilis inhibited down regulation of T beta RII mRNA, and protein levels in UVB irradiated human dermal fibroblasts consequently recover reduced type I procollagen synthesis. These results indicate UVB irradiation inhibits type I procollagen synthesis by suppression of TGF-beta/Smad signaling pathway, and FM of Z. mobilis has inhibitory effect on UVB-induced reduction of type I procollagen synthesis. While short period UVB irradiation decreased both T beta RII and type I procollagen protein levels in hairless mouse skin, topical application of FM of Z. mobilis prevented this decrease. Wrinkle formation in hairless mouse skin surface was accelerated by continuous 5 month UVB irradiation along with a reduction of type I collagen in the dermis, but this change was prevented by topical application of FM of Z. mobilis. From this experimental data, it is suggested that FM of Z. mobilis is effective for suppression of wrinkle formation in photoaging skin by inhibition of type I procollagen synthesis reduction.

Pulque production from fermented agave sap as a dietary supplement in Prehispanic Mesoamerica

PubMed Central

Correa-Ascencio, Marisol; Robertson, Ian G.; Cabrera-Cortés, Oralia; Cabrera-Castro, Rubén; Evershed, Richard P.

2014-01-01

Although in modern societies fermented beverages are associated with socializing, celebration, and ritual, in ancient times they were also importa`nt sources of essential nutrients and potable water. In Mesoamerica, pulque, an alcoholic beverage produced from the fermented sap of several species of maguey plants (Agavaceae; Fig. 1) is hypothesized to have been used as a dietary supplement and risk-buffering food in ancient Teotihuacan (150 B.C. to A.D. 650). Although direct archaeological evidence of pulque production is lacking, organic residue analysis of pottery vessels offers a new avenue of investigation. However, the chemical components of alcoholic beverages are water-soluble, greatly limiting their survival over archaeological timescales compared with hydrophobic lipids widely preserved in food residues. Hence, we apply a novel lipid biomarker approach that considers detection of bacteriohopanoids derived from the ethanol-producing bacterium Zymomonas mobilis for identifying pulque production/consumption in pottery vessels. Gas chromatography–mass spectrometry selected ion monitoring (m/z 191) of lipid extracts of >300 potsherds revealed characteristic bacteriohopanoid distributions in a subset of 14 potsherds. This hopanoid biomarker approach offers a new means of identifying commonly occurring bacterially fermented alcoholic beverages worldwide, including palm wine, beer, cider, perry, and other plant sap- or fruit-derived beverages [Swings J, De Ley J (1977) Bacteriol Rev 41(1):1–46]. PMID:25225408

Heterologous Expression of Plant Cell Wall Degrading Enzymes for Effective Production of Cellulosic Biofuels

PubMed Central

Jung, Sang-Kyu; Parisutham, Vinuselvi; Jeong, Seong Hun; Lee, Sung Kuk

2012-01-01

A major technical challenge in the cost-effective production of cellulosic biofuel is the need to lower the cost of plant cell wall degrading enzymes (PCDE), which is required for the production of sugars from biomass. Several competitive, low-cost technologies have been developed to produce PCDE in different host organisms such as Escherichia coli, Zymomonas mobilis, and plant. Selection of an ideal host organism is very important, because each host organism has its own unique features. Synthetic biology-aided tools enable heterologous expression of PCDE in recombinant E. coli or Z. mobilis and allow successful consolidated bioprocessing (CBP) in these microorganisms. In-planta expression provides an opportunity to simplify the process of enzyme production and plant biomass processing and leads to self-deconstruction of plant cell walls. Although the future of currently available technologies is difficult to predict, a complete and viable platform will most likely be available through the integration of the existing approaches with the development of breakthrough technologies. PMID:22911272

Bacterial supersystem for alginate import/metabolism and its environmental and bioenergy applications.

PubMed

Hashimoto, Wataru; Kawai, Shigeyuki; Murata, Kousaku

2010-01-01

Distinct from most alginate-assimilating bacteria that secrete polysaccharide lyases extracellularly, a gram-negative bacterium, Sphingomonas sp. A1 (strain A1), can directly incorporate alginate into its cytoplasm, without degradation, through a "superchannel" consisting of a mouth-like pit on the cell surface, periplasmic binding proteins, and a cytoplasmic membrane-bound ATP-binding cassette transporter. Flagellin homologues function as cell surface alginate receptors essential for expressing the superchannel. Cytoplasmic alginate lyases with different substrate specificities and action modes degrade the polysaccharide to its constituent monosaccharides. The resultant monosaccharides, α-keto acids, are converted to a reduced form by NADPH-dependent reductase, and are finally metabolized in the TCA cycle. Transplantation of the strain A1 superchannel to xenobiotic-degrading sphingomonads enhances bioremediation through the propagation of bacteria with an elevated transport activity. Furthermore, strain A1 cells transformed with Zymomonas mobilis genes for pyruvate decarboxylase and alcohol dehydrogenase II produce considerable amounts of biofuel ethanol from alginate when grown statically. © 2010 Landes Bioscience

Metabolically engineered glucose-utilizing Shewanella strains under anaerobic conditions.

PubMed

Choi, Donggeon; Lee, Sae Bom; Kim, Sohyun; Min, Byoungnam; Choi, In-Geol; Chang, In Seop

2014-02-01

Comparative genome analysis of Shewanella strains predicted that the strains metabolize preferably two- and three-carbon carbohydrates as carbon/electron source because many Shewanella genomes are deficient of the key enzymes in glycolysis (e.g., glucokinase). In addition, all Shewanella genomes are known to have only one set of genes associated with the phosphotransferase system required to uptake sugars. To engineer Shewanella strains that can utilize five- and six-carbon carbohydrates, we constructed glucose-utilizing Shewanella oneidensis MR-1 by introducing the glucose facilitator (glf; ZMO0366) and glucokinase (glk; ZMO0369) genes of Zymomonas mobilis. The engineered MR-1 strain was able to grow on glucose as a sole carbon/electron source under anaerobic conditions. The glucose affinity (Ks) and glucokinase activity in the engineered MR-1 strain were 299.46 mM and 0.259 ± 0.034 U/g proteins. The engineered strain was successfully applied to a microbial fuel cell system and exhibited current generation using glucose as the electron source. Copyright © 2013 Elsevier Ltd. All rights reserved.

Simultaneous saccharification and cofermentation of peracetic acid-pretreated biomass.

PubMed

Teixeira, L C; Linden, J C; Schroeder, H A

2000-01-01

Previous work in our laboratories has demonstrated the effectiveness of peracetic acid for improving enzymatic digestibility of lignocellulosic materials. The use of dilute alkali solutions as a pre-pretreatment prior to peracetic acid lignin oxidation increased carbohydrate hydrolysis yields in a synergistic as opposed to additive manner. Deacetylation of xylan is easily achieved using dilute alkali solutions under mild conditions. In this article, we evaluate the effectiveness of peracetic acid combined with an alkaline pre-pretreatment through simultaneous saccharification and cofermentation (SSCF) of pretreated hybrid poplar wood and sugar cane bagasse. Respective ethanol yields of 92.8 and 91.9% of theoretical are achieved using 6% NaOH/15% peracetic acid-pretreated substrates and recombinant Zymomonas mobilis CP4/pZB5. Reduction of acetyl groups of the lignocellulosic materials is demonstrated following alkaline pre-pretreatments. Such processing may be helpful in reducing peracetic acid requirements. The influence of deacetylation is more significant in combined pretreatments using lower peracetic acid loadings.

Simultaneous consumption of pentose and hexose sugars: an optimal microbial phenotype for efficient fermentation of lignocellulosic biomass.

PubMed

Kim, Jae-Han; Block, David E; Mills, David A

2010-11-01

Lignocellulosic biomass is an attractive carbon source for bio-based fuel and chemical production; however, its compositional heterogeneity hinders its commercial use. Since most microbes possess carbon catabolite repression (CCR), mixed sugars derived from the lignocellulose are consumed sequentially, reducing the efficacy of the overall process. To overcome this barrier, microbes that exhibit the simultaneous consumption of mixed sugars have been isolated and/or developed and evaluated for the lignocellulosic biomass utilization. Specific strains of Escherichia coli, Saccharomyces cerevisiae, and Zymomonas mobilis have been engineered for simultaneous glucose and xylose utilization via mutagenesis or introduction of a xylose metabolic pathway. Other microbes, such as Lactobacillus brevis, Lactobacillus buchneri, and Candida shehatae possess a relaxed CCR mechanism, showing simultaneous consumption of glucose and xylose. By exploiting CCR-negative phenotypes, various integrated processes have been developed that incorporate both enzyme hydrolysis of lignocellulosic material and mixed sugar fermentation, thereby enabling greater productivity and fermentation efficacy.

Simultaneous consumption of pentose and hexose sugars: an optimal microbial phenotype for efficient fermentation of lignocellulosic biomass

PubMed Central

Kim, Jae-Han; Block, David E.

2010-01-01

Lignocellulosic biomass is an attractive carbon source for bio-based fuel and chemical production; however, its compositional heterogeneity hinders its commercial use. Since most microbes possess carbon catabolite repression (CCR), mixed sugars derived from the lignocellulose are consumed sequentially, reducing the efficacy of the overall process. To overcome this barrier, microbes that exhibit the simultaneous consumption of mixed sugars have been isolated and/or developed and evaluated for the lignocellulosic biomass utilization. Specific strains of Escherichia coli, Saccharomyces cerevisiae, and Zymomonas mobilis have been engineered for simultaneous glucose and xylose utilization via mutagenesis or introduction of a xylose metabolic pathway. Other microbes, such as Lactobacillus brevis, Lactobacillus buchneri, and Candida shehatae possess a relaxed CCR mechanism, showing simultaneous consumption of glucose and xylose. By exploiting CCR-negative phenotypes, various integrated processes have been developed that incorporate both enzyme hydrolysis of lignocellulosic material and mixed sugar fermentation, thereby enabling greater productivity and fermentation efficacy. PMID:20838789

Three immobilized-cell columnar bioreactors for enhanced production of commodity chemicals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davison, B.H.; Scott, C.D.; Kaufman, E.N.

1993-07-01

Immobilized-cell fluidized-bed bioreactors (FBRS) can be used with a variety of fermentations to increase production of fuels, solvents, organic acids, and other fermentation products. Part of the increased rates and yields are due to the immobilization of the biocatalyst at high concentrations. This FBR system with immobilized Zymomonas mobiles increased ethanol productivity more than tenfold with 99% conversion and near stoichiometric yields. FBRs also offer several additional modes of operation for simultaneous fermentation and separation to further increase production by removing the inhibitory products directly from the continuous fermentation. The production of lactic acid by immobilized Lactobacillus was augmented withmore » the addition and removal of solid adsorbent particles to the FBR. An immiscible organic extractant also was used to extract butanol from the acetone-butanol fermentation by Clostridium acetobutylicum. Demonstrations with these FBR systems have already shown definite advantages by improved overall product yields (decreasing feed costs) and by increased rates (decreasing capital and operating costs). Further demonstration and scale-up continue.« less

Three immobilized-cell columnar bioreactors for enhanced production of commodity chemicals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davison, B.H.; Scott, C.D.; Kaufman, E.N.

1993-12-31

Immobilized-cell fluidized-bed bioreactors (FBRs) can be used with a variety of fermentations to increase production of fuels, solvents, organic acids, and other fermentation products. Part of the increased rates and yields are due to the immobilization of the biocatalyst at high concentrations. This FBR system with immobilized Zymomonas mobilis increased ethanol productivity more than tenfold with 99% conversion and near stoichiometric yields. FBRs also offer several additional modes of operation for simultaneous fermentation and separation to further increase production by removing the inhibitory products directly from the continuous fermentation. The production of lactic acid by immobilized Lactobacillus was augmented withmore » the addition and removal of solid adsorbent particles to the FBR. An immiscible organic extractant also was used to extract butanol from the acetone-butanol fermentation by Clostridium acetobutylicum. Demonstrations with these FBR systems have already shown definite advantages by improved overall product yields (decreasing feed costs) and by increased rates (decreasing capital and operating costs). Further demonstration and scale-up continue.« less

Bioethanol production from fermentable sugar juice.

PubMed

Zabed, Hossain; Faruq, Golam; Sahu, Jaya Narayan; Azirun, Mohd Sofian; Hashim, Rosli; Boyce, Amru Nasrulhaq

2014-01-01

Bioethanol production from renewable sources to be used in transportation is now an increasing demand worldwide due to continuous depletion of fossil fuels, economic and political crises, and growing concern on environmental safety. Mainly, three types of raw materials, that is, sugar juice, starchy crops, and lignocellulosic materials, are being used for this purpose. This paper will investigate ethanol production from free sugar containing juices obtained from some energy crops such as sugarcane, sugar beet, and sweet sorghum that are the most attractive choice because of their cost-effectiveness and feasibility to use. Three types of fermentation process (batch, fed-batch, and continuous) are employed in ethanol production from these sugar juices. The most common microorganism used in fermentation from its history is the yeast, especially, Saccharomyces cerevisiae, though the bacterial species Zymomonas mobilis is also potentially used nowadays for this purpose. A number of factors related to the fermentation greatly influences the process and their optimization is the key point for efficient ethanol production from these feedstocks.

Bioethanol Production from Fermentable Sugar Juice

PubMed Central

Zabed, Hossain; Faruq, Golam; Sahu, Jaya Narayan; Azirun, Mohd Sofian; Hashim, Rosli; Nasrulhaq Boyce, Amru

2014-01-01

Bioethanol production from renewable sources to be used in transportation is now an increasing demand worldwide due to continuous depletion of fossil fuels, economic and political crises, and growing concern on environmental safety. Mainly, three types of raw materials, that is, sugar juice, starchy crops, and lignocellulosic materials, are being used for this purpose. This paper will investigate ethanol production from free sugar containing juices obtained from some energy crops such as sugarcane, sugar beet, and sweet sorghum that are the most attractive choice because of their cost-effectiveness and feasibility to use. Three types of fermentation process (batch, fed-batch, and continuous) are employed in ethanol production from these sugar juices. The most common microorganism used in fermentation from its history is the yeast, especially, Saccharomyces cerevisiae, though the bacterial species Zymomonas mobilis is also potentially used nowadays for this purpose. A number of factors related to the fermentation greatly influences the process and their optimization is the key point for efficient ethanol production from these feedstocks. PMID:24715820

Simultaneous saccharification of inulin and starch using commercial glucoamylase and the subsequent bioconversion to high titer sorbitol and gluconic acid.

PubMed

An, Kehong; Hu, Fengxian; Bao, Jie

2013-12-01

A new bioprocess for production of sorbitol and gluconic acid from two low-cost feedstocks, inulin and cassava starch, using a commercially available enzyme was proposed in this study. The commercial glucoamylase GA-L NEW from Genencor was found to demonstrate a high inulinase activity for hydrolysis of inulin into fructose and glucose. The glucoamylase was used to replace the expensive and not commercially available inulinase enzyme for simultaneous saccharification of inulin and starch into high titer glucose and fructose hydrolysate. The glucose and fructose in the hydrolysate were converted into sorbitol and gluconic acid using immobilized whole cells of the recombinant Zymomonas mobilis strain. The high gluconic acid concentration of 193 g/L and sorbitol concentration of 180 g/L with the overall yield of 97.3 % were obtained in the batch operations. The present study provided a practical production method of sorbitol and gluconic acid from low cost feedstocks and enzymes.

Accounting for all sugars produced during integrated production of ethanol from lignocellulosic biomass.

PubMed

Schell, Daniel J; Dowe, Nancy; Chapeaux, Alexandre; Nelson, Robert S; Jennings, Edward W

2016-04-01

Accurate mass balance and conversion data from integrated operation is needed to fully elucidate the economics of biofuel production processes. This study explored integrated conversion of corn stover to ethanol and highlights techniques for accurate yield calculations. Acid pretreated corn stover (PCS) produced in a pilot-scale reactor was enzymatically hydrolyzed and the resulting sugars were fermented to ethanol by the glucose-xylose fermenting bacteria, Zymomonas mobilis 8b. The calculations presented here account for high solids operation and oligomeric sugars produced during pretreatment, enzymatic hydrolysis, and fermentation, which, if not accounted for, leads to overestimating ethanol yields. The calculations are illustrated for enzymatic hydrolysis and fermentation of PCS at 17.5% and 20.0% total solids achieving 80.1% and 77.9% conversion of cellulose and xylan to ethanol and ethanol titers of 63g/L and 69g/L, respectively. These procedures will be employed in the future and the resulting information used for techno-economic analysis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bioethanol production by heterologous expression of Pdc and AdhII in Streptomyces lividans.

PubMed

Lee, Jae Sun; Chi, Won-Jae; Hong, Soon-Kwang; Yang, Ji-Won; Chang, Yong Keun

2013-07-01

Two genes from Zymomonas mobilis that are responsible for ethanol production, pyruvate decarboxylase (pdc) and alcohol dehydrogenase II (adhII), were heterologously expressed in the Gram-positive bacterium Streptomyces lividans TK24. An examination of carbon distribution revealed that a significant portion of carbon metabolism was switched from biomass and organic acid biosynthesis to ethanol production upon the expression of pdc and adhII. The recombinant S. lividans TK24 produced ethanol from glucose with a yield of 23.7% based on the carbohydrate consumed. The recombinant was able to produce ethanol from xylose, L-arabinose, mannose, L-rhamnose, galactose, ribose, and cellobiose with yields of 16.0, 25.6, 21.5, 33.6, 30.6, 14.6, and 33.3%, respectively. Polymeric substances such as starch and xylan were directly converted to ethanol by the recombinant with ethanol yields of 18.9 and 8.8%, respectively. The recombinant S. lividans TK24/Tpet developed in this study is potentially a useful microbial resource for ethanol production from various sources of biomasses, especially microalgae.

Development and application of co-culture for ethanol production by co-fermentation of glucose and xylose: a systematic review.

PubMed

Chen, Yanli

2011-05-01

This article reviews current co-culture systems for fermenting mixtures of glucose and xylose to ethanol. Thirty-five co-culture systems that ferment either synthetic glucose and xylose mixture or various biomass hydrolysates are examined. Strain combinations, fermentation modes and conditions, and fermentation performance for these co-culture systems are compared and discussed. It is noted that the combination of Pichia stipitis with Saccharomyces cerevisiae or its respiratory-deficient mutant is most commonly used. One of the best results for fermentation of glucose and xylose mixture is achieved by using co-culture of immobilized Zymomonas mobilis and free cells of P. stipitis, giving volumetric ethanol production of 1.277 g/l/h and ethanol yield of 0.49-0.50 g/g. The review discloses that, as a strategy for efficient conversion of glucose and xylose, co-culture fermentation for ethanol production from lignocellulosic biomass can increase ethanol yield and production rate, shorten fermentation time, and reduce process costs, and it is a promising technology although immature.

Dissecting a complex chemical stress: chemogenomic profiling of plant hydrolysates

PubMed Central

Skerker, Jeffrey M; Leon, Dacia; Price, Morgan N; Mar, Jordan S; Tarjan, Daniel R; Wetmore, Kelly M; Deutschbauer, Adam M; Baumohl, Jason K; Bauer, Stefan; Ibáñez, Ana B; Mitchell, Valerie D; Wu, Cindy H; Hu, Ping; Hazen, Terry; Arkin, Adam P

2013-01-01

The efficient production of biofuels from cellulosic feedstocks will require the efficient fermentation of the sugars in hydrolyzed plant material. Unfortunately, plant hydrolysates also contain many compounds that inhibit microbial growth and fermentation. We used DNA-barcoded mutant libraries to identify genes that are important for hydrolysate tolerance in both Zymomonas mobilis (44 genes) and Saccharomyces cerevisiae (99 genes). Overexpression of a Z. mobilis tolerance gene of unknown function (ZMO1875) improved its specific ethanol productivity 2.4-fold in the presence of miscanthus hydrolysate. However, a mixture of 37 hydrolysate-derived inhibitors was not sufficient to explain the fitness profile of plant hydrolysate. To deconstruct the fitness profile of hydrolysate, we profiled the 37 inhibitors against a library of Z. mobilis mutants and we modeled fitness in hydrolysate as a mixture of fitness in its components. By examining outliers in this model, we identified methylglyoxal as a previously unknown component of hydrolysate. Our work provides a general strategy to dissect how microbes respond to a complex chemical stress and should enable further engineering of hydrolysate tolerance. PMID:23774757

Pyruvate decarboxylase and alcohol dehydrogenase overexpression in Escherichia coli resulted in high ethanol production and rewired metabolic enzyme networks.

PubMed

Yang, Mingfeng; Li, Xuefeng; Bu, Chunya; Wang, Hui; Shi, Guanglu; Yang, Xiushan; Hu, Yong; Wang, Xiaoqin

2014-11-01

Pyruvate decarboxylase and alcohol dehydrogenase are efficient enzymes for ethanol production in Zymomonas mobilis. These two enzymes were over-expressed in Escherichia coli, a promising candidate for industrial ethanol production, resulting in high ethanol production in the engineered E. coli. To investigate the intracellular changes to the enzyme overexpression for homoethanol production, 2-DE and LC-MS/MS were performed. More than 1,000 protein spots were reproducibly detected in the gel by image analysis. Compared to the wild-type, 99 protein spots showed significant changes in abundance in the recombinant E. coli, in which 46 were down-regulated and 53 were up-regulated. Most proteins related to tricarboxylic acid cycle, glycerol metabolism and other energy metabolism were up-regulated, whereas proteins involved in glycolysis and glyoxylate pathway were down-regulated, indicating the rewired metabolism in the engineered E. coli. As glycolysis is the main pathway for ethanol production, and it was inhibited significantly in engineered E. coli, further efforts should be directed at minimizing the repression of glycolysis to optimize metabolism network for higher yields of ethanol production.

Production of C4 and C5 branched-chain alcohols by engineered Escherichia. coli.

PubMed

Chen, Xiaoyan; Xu, Jingliang; Yang, Liu; Yuan, Zhenhong; Xiao, Shiyuan; Zhang, Yu; Liang, Cuiyi; He, Minchao; Guo, Ying

2015-11-01

Higher alcohols, longer chain alcohols, contain more than 3 carbon atoms, showed close energy advantages as gasoline, and were considered as the next generation substitution for chemical fuels. Higher alcohol biosynthesis by native microorganisms mainly needs gene expression of heterologous keto acid decarboxylase and alcohol dehydrogenases. In the present study, branched-chain α-keto acid decarboxylase gene from Lactococcus lactis subsp. lactis CICC 6246 (Kivd) and alcohol dehydrogenases gene from Zymomonas mobilis CICC 41465 (AdhB) were transformed into Escherichia coli for higher alcohol production. SDS-PAGE results showed these two proteins were expressed in the recombinant strains. The resulting strain was incubated in LB medium at 37 °C in Erlenmeyer flasks and much more 3-methyl-1-butanol (104 mg/L) than isobutanol (24 mg/L) was produced. However, in 5 g/L glucose-containing medium, the production of two alcohols was similar, 156 and 161 mg/L for C4 (isobutanol) and C5 (3-methyl-1-butanol) alcohol, respectively. Effects of fermentation factors including temperature, glucose content, and α-keto acid on alcohol production were also investigated. The increase of glucose content and the adding of α-keto acids facilitated the production of C4 and C5 alcohols. The enzyme activities of pure Kivd on α-ketoisovalerate and α-ketoisocaproate were 26.77 and 21.24 μmol min(-1) mg(-1), respectively. Due to its ability on decarboxylation of α-ketoisovalerate and α-ketoisocaproate, the recombinant E. coli strain showed potential application on isoamyl alcohol and isobutanol production.

Performance testing of Zymomonas mobilis metabolically engineered for cofermentation of glucose, xylose, and arabinose.

PubMed

Lawford, Hugh G; Rousseau, Joyce D

2002-01-01

IOGEN Corporation of Ottawa, Canada, has recently built a 40t/d biomass-to-ethanol demonstration plant adjacent to its enzyme production facility. It has partnered with the University of Toronto to test the C6/C5 cofermenta-tion performance characteristics of the National Renewable Energy Labora-tory's metabolically engineered Zymomonas mobilis using various biomass hydrolysates. IOGEN's feedstocks are primarily agricultural wastes such as corn stover and wheat straw. Integrated recombinant Z. mobilis strain AX101 grows on D-xylose and/or L-arabinose as the sole carbon/energy sources and ferments these pentose sugars to ethanol in high yield. Strain AX101 lacks the tetracycline resistance gene that was a common feature of other recombinant Zm constructs. Genomic integration provides reliable cofermentation performance in the absence of antibiotics, another characteristic making strain AX101 attractive for industrial cellulosic ethanol production. In this work, IOGEN's biomass hydrolysate was simulated by a pure sugar medium containing 6% (w/v) glucose, 3% xylose, and 0.35% arabinose. At a level of 3 g/L (dry solids), corn steep liquor with inorganic nitrogen (0.8 g/L of ammonium chloride or 1.2 g/L of diammonium phosphate) was a cost-effective nutritional supplement. In the absence of acetic acid, the maximum volumetric ethanol productivity of a continuous fermentation at pH 5.0 was 3.54 g/L x h. During prolonged continuous fermentation, the efficiency of sugar-to-ethanol conversion (based on total sugar load) was maintained at >85%. At a level of 0.25% (w/v) acetic acid, the productivity decreased to 1.17 g/L x h at pH 5.5. Unlike integrated, xylose-utilizing rec Zm strain C25, strain AX101 produces less lactic acid as byproduct, owing to the fact that the Escherichia coli arabinose genes are inserted into a region of the host chromosome tentatively assigned to the gene for D-lactic acid dehydrogenase. In pH-controlled batch fermentations with sugar mixtures, the order of sugar exhaustion from the medium was glucose followed by xylose and arabinose. Both the total sugar load and the sugar ratio were shown to be important determinants for efficient cofermentation. Ethanol at a level of 3% (w/v) was implicated as both inhibitory to pentose fermentation and as a potentiator of acetic acid inhibition of pentose fermentation at pH 5.5. The effect of ethanol may have been underestimated in other assessments of acetic acid sensitivity. This work underscores the importance of employing similar assay conditions in making comparative assessments of biocatalyst fermentation performance.

Fermentation of D-xylose and L-arabinose to ethanol by Erwinia chrysanthemi

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tolan, J.S.; Finn, R.K.

1987-09-01

Erwinia spp. are gram-negative facultative anaerobes within the family Enterobacteriacae which possess several desirable traits for the conversion of pentose sugars to ethanol, such as the ability to ferment a broad range of carbohydrates and the ease with which they can be genetically modified. Twenty-eight strains of Erwinia carotovora and E. chrysanthemi were screened for the ability to ferment D-xylose to ethanol. E. chrysanthemi B374 was chosen for further study on the basis of its superior (4%) ethanol tolerance. They have characterized the fermentation of D-xylose and L-arabinose by the wild type and mutants which bear plasmids containing the pyruvatemore » decarboxylase gene from Zymomonas mobilis. Expression of the gene markedly increased the yields of ethanol (from 0.7 up to 1.45 mol/mol of xylose) and decreased the yields of formate, acetate, and lactate. However, the cells with pyruvate decarboxylase grew only one-fourth as fast as the wild type and tolerated only 2% ethanol. Alcohol tolerance was stimulated by the addition of yeast extract to the growth medium. Xylose catabolism was characterized by a high saturation constant K/sub s/ (4.5 mM).« less

An in vivo, label-free quick assay for xylose transport in Escherichia coli.

PubMed

Chen, Tingjian; Zhang, Jingqing; Liang, Ling; Yang, Rong; Lin, Zhanglin

2009-07-01

Efficient use of xylose is necessary for economic production of biochemicals and biofuels from lignocellulosic materials. Current studies on xylose uptake for various microorganisms have been hampered by the lack of a facile assay for xylose transport. In this work, a rapid in vivo, label-free method for measuring xylose transport in Escherichia coli was developed by taking advantage of the Bacillus pumilus xylosidase (XynB), which cleaved a commercially available xylose analog, p-nitrophenyl-beta-d-xylopyranoside (pNPX), to release a chromogenic group, p-nitrophenol (pNP). XynB was expressed alone or in conjunction with a Zymomonas mobilis glucose facilitator protein (Glf) capable of transporting xylose. This XynB-mediated transport assay was demonstrated in test tubes and 96-well plates with submicromolar concentrations of pNPX. Kinetic inhibition experiments validated that pNPX and xylose were competitive substrates for the transport process, and the addition of glucose (20 g/L) in the culture medium clearly diminished the transmembrane transport of pNPX and, thus, mimicked its inhibitory action on xylose uptake. This method should be useful for engineering of the xylose transport process in E. coli, and similar assay schemes can be extended to other microorganisms.

Conditioning of dilute-acid pretreated corn stover hydrolysate liquors by treatment with lime or ammonium hydroxide to improve conversion of sugars to ethanol.

PubMed

Jennings, Edward W; Schell, Daniel J

2011-01-01

Dilute-acid pretreatment of lignocellulosic biomass enhances the ability of enzymes to hydrolyze cellulose to glucose, but produces many toxic compounds that inhibit fermentation of sugars to ethanol. The objective of this study was to compare the effectiveness of treating hydrolysate liquor with Ca(OH)2 and NH4OH for improving ethanol yields. Corn stover was pretreated in a pilot-scale reactor and then the liquor fraction (hydrolysate) was extracted and treated with various amounts of Ca(OH)2 or NH4OH at several temperatures. Glucose and xylose in the treated liquor were fermented to ethanol using a glucose-xylose fermenting bacteria, Zymomonas mobilis 8b. Sugar losses up to 10% occurred during treatment with Ca(OH)2, but these losses were two to fourfold lower with NH4OH treatment. Ethanol yields for NH4OH-treated hydrolysate were 33% greater than those achieved in Ca(OH)2-treated hydrolysate and pH adjustment to either 6.0 or 8.5 with NH4OH prior to fermentation produced equivalent ethanol yields. Copyright © 2010 Elsevier Ltd. All rights reserved.

Metabolic characterization and transformation of the non-dairy Lactococcus lactis strain KF147, for production of ethanol from xylose.

PubMed

Petersen, Kia Vest; Liu, Jianming; Chen, Jun; Martinussen, Jan; Jensen, Peter Ruhdal; Solem, Christian

2017-08-01

The non-dairy lactic acid bacterium Lactococcus lactis KF147 can utilize xylose as the sole energy source. To assess whether KF147 could serve as a platform organism for converting second generation sugars into useful chemicals, the authors characterized growth and product formation for KF147 when grown on xylose. In a defined medium KF147 was found to co-metabolize xylose and arginine, resulting in bi-phasic growth. Especially at low xylose concentrations, arginine significantly improved growth rate. To facilitate further studies of the xylose metabolism, the authors eliminated arginine catabolism by deleting the arcA gene encoding the arginine deiminase. The fermentation product profile suggested two routes for xylose degradation, the phosphoketolase pathway and the pentose phosphate pathway. Inactivation of the phosphoketolase pathway redirected the entire flux through the pentose phosphate pathway whereas over-expression of phosphoketolase increased the flux through the phosphoketolase pathway. In general, significant amounts of the mixed-acid products, including lactate, formate, acetate and ethanol, were formed irrespective of xylose concentrations. To demonstrate the potential of KF147 for converting xylose into useful chemicals the authors chose to redirect metabolism towards ethanol production. A synthetic promoter library was used to drive the expression of codon-optimized versions of the Zymomonas mobilis genes encoding pyruvate decarboxylase and alcohol dehydrogenase, and the outcome was a strain producing ethanol as the sole fermentation product with a high yield corresponding to 83% of the theoretical maximum. The results clearly indicate the great potential of using the more metabolically diverse non-dairy L. lactis strains for bio-production based on xylose containing feedstocks. Copyright © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Studying the rapid bioconversion of lignocellulosic sugars into ethanol using high cell density fermentations with cell recycle

PubMed Central

2014-01-01

Background The Rapid Bioconversion with Integrated recycle Technology (RaBIT) process reduces capital costs, processing times, and biocatalyst cost for biochemical conversion of cellulosic biomass to biofuels by reducing total bioprocessing time (enzymatic hydrolysis plus fermentation) to 48 h, increasing biofuel productivity (g/L/h) twofold, and recycling biocatalysts (enzymes and microbes) to the next cycle. To achieve these results, RaBIT utilizes 24-h high cell density fermentations along with cell recycling to solve the slow/incomplete xylose fermentation issue, which is critical for lignocellulosic biofuel fermentations. Previous studies utilizing similar fermentation conditions showed a decrease in xylose consumption when recycling cells into the next fermentation cycle. Eliminating this decrease is critical for RaBIT process effectiveness for high cycle counts. Results Nine different engineered microbial strains (including Saccharomyces cerevisiae strains, Scheffersomyces (Pichia) stipitis strains, Zymomonas mobilis 8b, and Escherichia coli KO11) were tested under RaBIT platform fermentations to determine their suitability for this platform. Fermentation conditions were then optimized for S. cerevisiae GLBRCY128. Three different nutrient sources (corn steep liquor, yeast extract, and wheat germ) were evaluated to improve xylose consumption by recycled cells. Capacitance readings were used to accurately measure viable cell mass profiles over five cycles. Conclusion The results showed that not all strains are capable of effectively performing the RaBIT process. Acceptable performance is largely correlated to the specific xylose consumption rate. Corn steep liquor was found to reduce the deleterious impacts of cell recycle and improve specific xylose consumption rates. The viable cell mass profiles indicated that reduction in specific xylose consumption rate, not a drop in viable cell mass, was the main cause for decreasing xylose consumption. PMID:24847379

Bioethanol production from leafy biomass of mango (Mangifera indica) involving naturally isolated and recombinant enzymes.

PubMed

Das, Saprativ P; Ravindran, Rajeev; Deka, Deepmoni; Jawed, Mohammad; Das, Debasish; Goyal, Arun

2013-01-01

The present study describes the usage of dried leafy biomass of mango (Mangifera indica) containing 26.3% (w/w) cellulose, 54.4% (w/w) hemicellulose, and 16.9% (w/w) lignin, as a substrate for bioethanol production from Zymomonas mobilis and Candida shehatae. The substrate was subjected to two different pretreatment strategies, namely, wet oxidation and an organosolv process. An ethanol concentration (1.21 g/L) was obtained with Z. mobilis in a shake-flask simultaneous saccharification and fermentation (SSF) trial using 1% (w/v) wet oxidation pretreated mango leaves along with mixed enzymatic consortium of Bacillus subtilis cellulase and recombinant hemicellulase (GH43), whereas C. shehatae gave a slightly higher (8%) ethanol titer of 1.31 g/L. Employing 1% (w/v) organosolv pretreated mango leaves and using Z. mobilis and C. shehatae separately in the SSF, the ethanol titers of 1.33 g/L and 1.52 g/L, respectively, were obtained. The SSF experiments performed with 5% (w/v) organosolv-pretreated substrate along with C. shehatae as fermentative organism gave a significantly enhanced ethanol titer value of 8.11 g/L using the shake flask and 12.33 g/L at the bioreactor level. From the bioreactor, 94.4% (v/v) ethanol was recovered by rotary evaporator with 21% purification efficiency.

Bidirectional reaction steps in metabolic networks: I. Modeling and simulation of carbon isotope labeling experiments.

PubMed

Wiechert, W; de Graaf, A A

1997-07-05

The extension of metabolite balancing with carbon labeling experiments, as described by Marx et al. (Biotechnol. Bioeng. 49: 11-29), results in a much more detailed stationary metabolic flux analysis. As opposed to basic metabolite flux balancing alone, this method enables both flux directions of bidirectional reaction steps to be quantitated. However, the mathematical treatment of carbon labeling systems is much more complicated, because it requires the solution of numerous balance equations that are bilinear with respect to fluxes and fractional labeling. In this study, a universal modeling framework is presented for describing the metabolite and carbon atom flux in a metabolic network. Bidirectional reaction steps are extensively treated and their impact on the system's labeling state is investigated. Various kinds of modeling assumptions, as usually made for metabolic fluxes, are expressed by linear constraint equations. A numerical algorithm for the solution of the resulting linear constrained set of nonlinear equations is developed. The numerical stability problems caused by large bidirectional fluxes are solved by a specially developed transformation method. Finally, the simulation of carbon labeling experiments is facilitated by a flexible software tool for network synthesis. An illustrative simulation study on flux identifiability from available flux and labeling measurements in the cyclic pentose phosphate pathway of a recombinant strain of Zymomonas mobilis concludes this contribution.

Bacterial diversity in the active stage of a bioremediation system for mineral oil hydrocarbon-contaminated soils.

PubMed

Popp, Nicole; Schlömann, Michael; Mau, Margit

2006-11-01

Soils contaminated with mineral oil hydrocarbons are often cleaned in off-site bioremediation systems. In order to find out which bacteria are active during the degradation phase in such systems, the diversity of the active microflora in a degrading soil remediation system was investigated by small-subunit (SSU) rRNA analysis. Two sequential RNA extracts from one soil sample were generated by a procedure incorporating bead beating. Both extracts were analysed separately by generating individual SSU rDNA clone libraries from cDNA of the two extracts. The sequencing results showed moderate diversity. The two clone libraries were dominated by Gammaproteobacteria, especially Pseudomonas spp. Alphaproteobacteria and Betaproteobacteria were two other large groups in the clone libraries. Actinobacteria, Firmicutes, Bacteroidetes and Epsilonproteobacteria were detected in lower numbers. The obtained sequences were predominantly related to genera for which cultivated representatives have been described, but were often clustered together in the phylogenetic tree, and the sequences that were most similar were originally obtained from soils and not from pure cultures. Most of the dominant genera in the clone libraries, e.g. Pseudomonas, Acinetobacter, Sphingomonas, Acidovorax and Thiobacillus, had already been detected in (mineral oil hydrocarbon) contaminated environmental samples. The occurrence of the genera Zymomonas and Rhodoferax was novel in mineral oil hydrocarbon-contaminated soil.

Sequence-based analysis of the microbial composition of water kefir from multiple sources.

PubMed

Marsh, Alan J; O'Sullivan, Orla; Hill, Colin; Ross, R Paul; Cotter, Paul D

2013-11-01

Water kefir is a water-sucrose-based beverage, fermented by a symbiosis of bacteria and yeast to produce a final product that is lightly carbonated, acidic and that has a low alcohol percentage. The microorganisms present in water kefir are introduced via water kefir grains, which consist of a polysaccharide matrix in which the microorganisms are embedded. We aimed to provide a comprehensive sequencing-based analysis of the bacterial population of water kefir beverages and grains, while providing an initial insight into the corresponding fungal population. To facilitate this objective, four water kefirs were sourced from the UK, Canada and the United States. Culture-independent, high-throughput, sequencing-based analyses revealed that the bacterial fraction of each water kefir and grain was dominated by Zymomonas, an ethanol-producing bacterium, which has not previously been detected at such a scale. The other genera detected were representatives of the lactic acid bacteria and acetic acid bacteria. Our analysis of the fungal component established that it was comprised of the genera Dekkera, Hanseniaspora, Saccharomyces, Zygosaccharomyces, Torulaspora and Lachancea. This information will assist in the ultimate identification of the microorganisms responsible for the potentially health-promoting attributes of these beverages. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Classification of Rhizomonas suberifaciens, an unnamed Rhizomonas species, and Sphingomonas spp. in rRNA superfamily IV.

PubMed

van Bruggen, A H; Jochimsen, K N; Steinberger, E M; Segers, P; Gillis, M

1993-01-01

Thermal melting profiles of hybrids between 3H-labeled rRNA of Rhizomonas suberifaciens, the causal agent of corky root of lettuce, and chromosomal DNAs from 27 species of gram-negative bacteria indicated that the genus Rhizomonas belongs to superfamily IV of De Ley. On the basis of the melting temperatures of DNA hybrids with rRNAs from the type strains of R. suberifaciens, Sphingomonas paucimobilis, and Sphingomonas capsulata, Rhizomonas strains constitute a separate branch in superfamily IV, which is closely related to but separate from branches containing Zymomonas mobilis, Sphingomonas spp., and S. capsulata. Sphingomonas yanoikuyae and Rhizomonas sp. strain WI4 are located toward the base of the Rhizomonas rRNA branch. DNA-DNA hybridization indicated that S. yanoikuyae is equidistant from Rhizomonas sp. strain WI4 and S. paucimobilis. Sequences of 270 bp of 16S ribosomal DNAs from eight strains of Rhizomonas spp., eight strains of Sphingomonas spp., and Agrobacterium tumefaciens indicated that S. yanoikuyae and Rhizomonas sp. strains WI4 and CA16 are genetically more closely related to R. suberifaciens than to Sphingomonas spp. Thus, S. yanoikuyae may need to be transferred to the genus Rhizomonas on the basis of the results of further study.

Thermophilic Bacillus coagulans requires less cellulases for simultaneous saccharification and fermentation of cellulose to products than mesophilic microbial biocatalysts.

PubMed

Ou, Mark S; Mohammed, Nazimuddin; Ingram, L O; Shanmugam, K T

2009-05-01

Ethanol production from lignocellulosic biomass depends on simultaneous saccharification of cellulose to glucose by fungal cellulases and fermentation of glucose to ethanol by microbial biocatalysts (SSF). The cost of cellulase enzymes represents a significant challenge for the commercial conversion of lignocellulosic biomass into renewable chemicals such as ethanol and monomers for plastics. The cellulase concentration for optimum SSF of crystalline cellulose with fungal enzymes and a moderate thermophile, Bacillus coagulans, was determined to be about 7.5 FPU g(-1) cellulose. This is about three times lower than the amount of cellulase required for SSF with Saccharomyces cerevisiae, Zymomonas mobilis, or Lactococcus lactis subsp. lactis whose growth and fermentation temperature optimum is significantly lower than that of the fungal cellulase activity. In addition, B. coagulans also converted about 80% of the theoretical yield of products from 40 g/L of crystalline cellulose in about 48 h of SSF with 10 FPU g(-1) cellulose while yeast, during the same period, only produced about 50% of the highest yield produced at end of 7 days of SSF. These results show that a match in the temperature optima for cellulase activity and fermentation is essential for decreasing the cost of cellulase in cellulosic ethanol production.

Confronting Space Debris: Strategies and Warnings from Comparable Examples Including Deepwater Horizon

DTIC Science & Technology

2010-01-01

Horizon (DH) was an ultra deepwater , semisubmers- ible offshore drilling rig contracted to BP by its owner, Transocean. The rig was capable of...Warnings from Comparable Examples Including Deepwater Horizon 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...research quality and objectivity. StrategieS and WarningS from Comparable exampleS inCluding deepWater Horizon Confronting SpaCe DebriS dave baiocchi

Optical contact micrometer

DOEpatents

Jacobson, Steven D.

2014-08-19

Certain examples provide optical contact micrometers and methods of use. An example optical contact micrometer includes a pair of opposable lenses to receive an object and immobilize the object in a position. The example optical contact micrometer includes a pair of opposable mirrors positioned with respect to the pair of lenses to facilitate viewing of the object through the lenses. The example optical contact micrometer includes a microscope to facilitate viewing of the object through the lenses via the mirrors; and an interferometer to obtain one or more measurements of the object.

48 CFR 1845.7101-1 - Property classification.

Code of Federal Regulations, 2010 CFR

2010-10-01

... aeronautical and space programs, which are capable of stand-alone operation. Examples include research aircraft... characteristics. (ii) Examples of NASA heritage assets include buildings and structures designated as National...., it no longer provides service to NASA operations). Examples of obsolete property are items in...

48 CFR 1845.7101-1 - Property classification.

Code of Federal Regulations, 2011 CFR

2011-10-01

... aeronautical and space programs, which are capable of stand-alone operation. Examples include research aircraft... characteristics. (ii) Examples of NASA heritage assets include buildings and structures designated as National...., it no longer provides service to NASA operations). Examples of obsolete property are items in...

48 CFR 1845.7101-1 - Property classification.

Code of Federal Regulations, 2014 CFR

2014-10-01

... aeronautical and space programs, which are capable of stand-alone operation. Examples include research aircraft... characteristics. (ii) Examples of NASA heritage assets include buildings and structures designated as National...., it no longer provides service to NASA operations). Examples of obsolete property are items in...

48 CFR 1845.7101-1 - Property classification.

Code of Federal Regulations, 2013 CFR

2013-10-01

... aeronautical and space programs, which are capable of stand-alone operation. Examples include research aircraft... characteristics. (ii) Examples of NASA heritage assets include buildings and structures designated as National...., it no longer provides service to NASA operations). Examples of obsolete property are items in...

48 CFR 1845.7101-1 - Property classification.

Code of Federal Regulations, 2012 CFR

2012-10-01

... aeronautical and space programs, which are capable of stand-alone operation. Examples include research aircraft... characteristics. (ii) Examples of NASA heritage assets include buildings and structures designated as National...., it no longer provides service to NASA operations). Examples of obsolete property are items in...

Development of corn silk as a biocarrier for Zymomonas mobilis biofilms in ethanol production from rice straw.

PubMed

Todhanakasem, Tatsaporn; Tiwari, Rashmi; Thanonkeo, Pornthap

2016-01-01

Z. mobilis cell immobilization has been proposed as an effective means of improving ethanol production. In this work, polystyrene and corn silk were used as biofilm developmental matrices for Z. mobilis ethanol production with rice straw hydrolysate as a substrate. Rice straw was hydrolyzed by dilute sulfuric acid (H2SO4) and enzymatic hydrolysis. The final hydrolysate contained furfural (271.95 ± 76.30 ppm), 5-hydroxymethyl furfural (0.07 ± 0.00 ppm), vanillin (1.81 ± 0.00 ppm), syringaldehyde (5.07 ± 0.83 ppm), 4-hydroxybenzaldehyde (4-HB) (2.39 ± 1.20 ppm) and acetic acid (0.26 ± 0.08%). Bacterial attachment or biofilm formation of Z. mobilis strain TISTR 551 on polystyrene and delignified corn silk carrier provided significant ethanol yields. Results showed up to 0.40 ± 0.15 g ethanol produced/g glucose consumed when Z. mobilis was immobilized on a polystyrene carrier and 0.51 ± 0.13 g ethanol produced/g glucose consumed when immobilized on delignified corn silk carrier under batch fermentation by Z. mobilis TISTR 551 biofilm. The higher ethanol yield from immobilized, rather than free living, Z. mobilis could possibly be explained by a higher cell density, better control of anaerobic conditions and higher toxic tolerance of Z. mobilis biofilms over free cells.

Enabling Unbalanced Fermentations by Using Engineered Electrode-Interfaced Bacteria

PubMed Central

Flynn, Jeffrey M.; Ross, Daniel E.; Hunt, Kristopher A.; Bond, Daniel R.; Gralnick, Jeffrey A.

2010-01-01

Cellular metabolism is a series of tightly linked oxidations and reductions that must be balanced. Recycling of intracellular electron carriers during fermentation often requires substrate conversion to undesired products, while respiration demands constant addition of electron acceptors. The use of electrode-based electron acceptors to balance biotransformations may overcome these constraints. To test this hypothesis, the metal-reducing bacterium Shewanella oneidensis was engineered to stoichiometrically convert glycerol into ethanol, a biotransformation that will not occur unless two electrons are removed via an external reaction, such as electrode reduction. Multiple modules were combined into a single plasmid to alter S. oneidensis metabolism: a glycerol module, consisting of glpF, glpK, glpD, and tpiA from Escherichia coli, and an ethanol module containing pdc and adh from Zymomonas mobilis. A further increase in product yields was accomplished through knockout of pta, encoding phosphate acetyltransferase, shifting flux toward ethanol and away from acetate production. In this first-generation demonstration, conversion of glycerol to ethanol required the presence of an electrode to balance the reaction, and electrode-linked rates were on par with volumetric conversion rates observed in engineered E. coli. Linking microbial biocatalysis to current production can eliminate redox constraints by shifting other unbalanced reactions to yield pure products and serve as a new platform for next-generation bioproduction strategies. PMID:21060736

Fermentation of xylose to ethanol by genetically modified enteric bacteria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tolan, J.S.

1987-01-01

This thesis describes the fermentation of D-xylose by wild type and recombinant Klebsiella planticola ATCC 33531 and Erwinia chrysanthemi B374. The recombinant strains bear multi-copy plasmids containing the pdc gene inserted from Zymomonas mobilis. Expression of the gene in K. planticola markedly increased the yield of ethanol, up to 1.3 mole/mole xylose, or 25.1 g/L. Concurrently, there were significant decreases in the yields of formation acetate, lactate, and butanediol. Transconjugant Klebsiella grew almost as fast as the wild type and tolerated up to 4% ethanol. The plasmid was retained by the cells during at least one batch culture, even inmore » the absence of selective pressure by antibiotics to maintain the plasmid. The cells produced 31.6 g/L ethanol from 79.6 g/L of a D-glucose-D-xylose-L-arabinose mixture designed to simulate hydrolyzed hemicellulose. The physiology of the wild type K. planticola is described in more detail than in the original report of its isolation. E. chrysanthemi PDC transconjugants also produced ethanol in high yield (up to 1.45 mole/mole xylose). However, transconjugant E. chrysanthemi grew only 1/4 as rapidly as the wild type and tolerated only 2% ethanol. The plasmid PZM15 apparently exhibits pleiotropic effects when inserted into K. planticola and into E. chrysanthemi.« less

Persistent Infrared Spectral Hole-Burning for Impurity Vibrational Modes in Solids.

DTIC Science & Technology

1986-09-30

infrared vibrational transitions of impurity molecules in solids. Examples include 1,2- difluoroethane in rare gas matrices, perrhenate ions in alkali...observed consists of infrared vibrational transitions of impurity molecules in solids. Examples include 1,2- difluoroethane in rare gas matrices...solids. Examples include 1,2- difluoroethane in rare gas matrices, perrhenate ions in alkali halide crystals, and most recently, cyanide and nitrite

Examples as an Instructional Tool in Mathematics and Science Classrooms: Teachers' Perceptions and Attitudes

ERIC Educational Resources Information Center

Huang, Xiaoxia; Cribbs, Jennifer

2017-01-01

This study examined mathematics and science teachers' perceptions and use of four types of examples, including typical textbook examples (standard worked examples) and erroneous worked examples in the written form as well as mastery modelling examples and peer modelling examples involving the verbalization of the problem-solving process. Data…

Exercise Habit

MedlinePlus

... and lungs. Examples of aerobic exercise include walking, hiking, running, aerobic dance, biking, rowing, swimming, and cross- ... Examples of weight-bearing exercise include walking, yoga, hiking, climbing stairs, playing tennis, dancing, and strength training. ...

Images that Twist and Turn.

ERIC Educational Resources Information Center

Hubbard, Guy

2002-01-01

Discusses various art movements that include examples of artworks with movement, such as Romantic, Classic, Rococo, and Art Nouveau. Addresses ways in which students can learn to incorporate movement into their own works of art. Includes examples of artists who included movement into their artworks. (CMK)

Towards an informative mutant phenotype for every bacterial gene

DOE PAGES

Deutschbauer, Adam; Price, Morgan N.; Wetmore, Kelly M.; ...

2014-08-11

Mutant phenotypes provide strong clues to the functions of the underlying genes and could allow annotation of the millions of sequenced yet uncharacterized bacterial genes. However, it is not known how many genes have a phenotype under laboratory conditions, how many phenotypes are biologically interpretable for predicting gene function, and what experimental conditions are optimal to maximize the number of genes with a phenotype. To address these issues, we measured the mutant fitness of 1,586 genes of the ethanol-producing bacterium Zymomonas mobilis ZM4 across 492 diverse experiments and found statistically significant phenotypes for 89% of all assayed genes. Thus, inmore » Z. mobilis, most genes have a functional consequence under laboratory conditions. We demonstrate that 41% of Z. mobilis genes have both a strong phenotype and a similar fitness pattern (cofitness) to another gene, and are therefore good candidates for functional annotation using mutant fitness. Among 502 poorly characterized Z. mobilis genes, we identified a significant cofitness relationship for 174. For 57 of these genes without a specific functional annotation, we found additional evidence to support the biological significance of these gene-gene associations, and in 33 instances, we were able to predict specific physiological or biochemical roles for the poorly characterized genes. Last, we identified a set of 79 diverse mutant fitness experiments in Z. mobilis that are nearly as biologically informative as the entire set of 492 experiments. Therefore, our work provides a blueprint for the functional annotation of diverse bacteria using mutant fitness.« less

Biosynthetic burden and plasmid burden limit expression of chromosomally integrated heterologous genes (pdc, adhB) in Escherichia coli

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martinez, A.; York, S.W.; Yomano, L.P.

1999-10-01

Previous studies have shown an unexpectedly high nutrient requirement for efficient ethanol production by ethanologenic recombinants of Escherichia coli B such as LY01 which contain chromosomally integrated Zymomonas mobilis genes (pdc, adhB) encoding the ethanol pathway. The basis for this requirement has been identified as a media-dependent effect on the expression of the Z. mobilis genes rather than a nutritional limitation. Ethanol production was substantially increased without additional nutrients simply by increasing the level of pyruvate decarboxylase activity. This was accomplished by adding a multicopy plasmid containing pdc alone (but not adhB alone) to strain LY01, and by adding multicopymore » plasmids which express pdc and adhB from strong promoters. New strong promoters were isolated from random fragments of Z. mobilis DNA and characterized but were not used to construct integrated biocatalysts. These promoters contained regions resembling recognition sites for 3 different E. coli sigma factors: {sigma}{sup 70}, {sigma}{sup 38}, and {sigma}{sup 28}. The most effective plasmid-based promoters for fermentation were recognized by multiple sigma factors, expressed both pdc and adhB at high levels, and produced ethanol efficiently while allowing up to 80% reduction in complex nutrients as compared to LY01. The ability to utilize multiple sigma factors may be advantageous to maintain the high levels of PDC and ADH needed for efficient ethanol production throughout batch fermentation.« less

Synthesis and biological activity of lipophilic analogs of the cationic antimicrobial active peptide anoplin.

PubMed

Chionis, Kostas; Krikorian, Dimitrios; Koukkou, Anna-Irini; Sakarellos-Daitsiotis, Maria; Panou-Pomonis, Eugenia

2016-11-01

Anoplin is a short natural cationic antimicrobial peptide which is derived from the venom sac of the solitary wasp, Anoplius samariensis. Due to its short sequence G 1 LLKR 5 IKT 8 LL-NH 2 , it is ideal for research tests. In this study, novel analogs of anoplin were prepared and examined for their antimicrobial, hemolytic activity, and proteolytic stability. Specific substitutions were introduced in amino acids Gly 1 , Arg 5 , and Thr 8 and lipophilic groups with different lengths in the N-terminus in order to investigate how these modifications affect their antimicrobial activity. These cationic analogs exhibited higher antimicrobial activity than the native peptide; they are also nontoxic at their minimum inhibitory concentration (MIC) values and resistant to enzymatic degradation. The substituted peptide GLLKF 5 IKK 8 LL-NH 2 exhibited high activity against Gram-negative bacterium Zymomonas mobilis (MIC = 7 µg/ml), and the insertion of octanoic, decanoic, and dodecanoic acid residues in its N-terminus increased the antimicrobial activity against Gram-positive and Gram-negative bacteria (MIC = 5 µg/ml). The conformational characteristics of the peptide analogs were studied by circular dichroism. Structure activity studies revealed that the substitution of specific amino acids and the incorporation of lipophilic groups enhanced the amphipathic α-helical conformation inducing better antimicrobial effects. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd.

Novel Xylose Dehydrogenase in the Halophilic Archaeon Haloarcula marismortui†

PubMed Central

Johnsen, Ulrike; Schönheit, Peter

2004-01-01

During growth of the halophilic archaeon Haloarcula marismortui on d-xylose, a specific d-xylose dehydrogenase was induced. The enzyme was purified to homogeneity. It constitutes a homotetramer of about 175 kDa and catalyzed the oxidation of xylose with both NADP+ and NAD+ as cosubstrates with 10-fold higher affinity for NADP+. In addition to d-xylose, d-ribose was oxidized at similar kinetic constants, whereas d-glucose was used with about 70-fold lower catalytic efficiency (kcat/Km). With the N-terminal amino acid sequence of the subunit, an open reading frame (ORF)—coding for a 39.9-kDA protein—was identified in the partially sequenced genome of H. marismortui. The function of the ORF as the gene designated xdh and coding for xylose dehydrogenase was proven by its functional overexpression in Escherichia coli. The recombinant enzyme was reactivated from inclusion bodies following solubilization in urea and refolding in the presence of salts, reduced and oxidized glutathione, and substrates. Xylose dehydrogenase showed the highest sequence similarity to glucose-fructose oxidoreductase from Zymomonas mobilis and other putative bacterial and archaeal oxidoreductases. Activities of xylose isomerase and xylulose kinase, the initial reactions of xylose catabolism of most bacteria, could not be detected in xylose-grown cells of H. marismortui, and the genes that encode them, xylA and xylB, were not found in the genome of H. marismortui. Thus, we propose that this first characterized archaeal xylose dehydrogenase catalyzes the initial step in xylose degradation by H. marismortui. PMID:15342590

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deutschbauer, Adam; Price, Morgan N.; Wetmore, Kelly M.

Mutant phenotypes provide strong clues to the functions of the underlying genes and could allow annotation of the millions of sequenced yet uncharacterized bacterial genes. However, it is not known how many genes have a phenotype under laboratory conditions, how many phenotypes are biologically interpretable for predicting gene function, and what experimental conditions are optimal to maximize the number of genes with a phenotype. To address these issues, we measured the mutant fitness of 1,586 genes of the ethanol-producing bacterium Zymomonas mobilis ZM4 across 492 diverse experiments and found statistically significant phenotypes for 89% of all assayed genes. Thus, inmore » Z. mobilis, most genes have a functional consequence under laboratory conditions. We demonstrate that 41% of Z. mobilis genes have both a strong phenotype and a similar fitness pattern (cofitness) to another gene, and are therefore good candidates for functional annotation using mutant fitness. Among 502 poorly characterized Z. mobilis genes, we identified a significant cofitness relationship for 174. For 57 of these genes without a specific functional annotation, we found additional evidence to support the biological significance of these gene-gene associations, and in 33 instances, we were able to predict specific physiological or biochemical roles for the poorly characterized genes. Last, we identified a set of 79 diverse mutant fitness experiments in Z. mobilis that are nearly as biologically informative as the entire set of 492 experiments. Therefore, our work provides a blueprint for the functional annotation of diverse bacteria using mutant fitness.« less

Impact of recycling stillage on conversion of dilute sulfuric acid pretreated corn stover to ethanol.

PubMed

Mohagheghi, Ali; Schell, Daniel J

2010-04-01

Both the current corn starch to ethanol industry and the emerging lignocellulosic biofuels industry view recycling of spent fermentation broth or stillage as a method to reduce fresh water use. The objective of this study was to understand the impact of recycling stillage on conversion of corn stover to ethanol. Sugars in a dilute-acid pretreated corn stover hydrolysate were fermented to ethanol by the glucose-xylose fermenting bacteria Zymomonas mobilis 8b. Three serial fermentations were performed at two different initial sugar concentrations using either 10% or 25% of the stillage as makeup water for the next fermentation in the series. Serial fermentations were performed to achieve near steady state concentration of inhibitors and other compounds in the corn stover hydrolysate. Little impact on ethanol yields was seen at sugar concentrations equivalent to pretreated corn stover slurry at 15% (w/w) with 10% recycle of the stillage. However, ethanol yields became progressively poorer as the sugar concentration increased and fraction of the stillage recycled increased. At an equivalent corn stover slurry concentration of 20% with 25% recycled stillage the ethanol yield was only 5%. For this microorganism with dilute-acid pretreated corn stover, recycling a large fraction of the stillage had a significant negative impact on fermentation performance. Although this finding is of concern for biochemical-based lignocellulose conversion processes, other microorganism/pretreatment technology combinations will likely perform differently. (c) 2009 Wiley Periodicals, Inc.

Example-Based Learning: Effects of Different Types of Examples on Student Performance, Cognitive Load and Self-Efficacy in a Statistical Learning Task

ERIC Educational Resources Information Center

Huang, Xiaoxia

2017-01-01

Previous research has indicated the disconnect between example-based research focusing on worked examples (WEs) and that focusing on modeling examples. The purpose of this study was to examine and compare the effect of four different types of examples from the two separate lines of research, including standard WEs, erroneous WEs, expert (masterly)…

45 CFR 612.7 - Exemptions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... to which the information pertains. Examples of records exempt from disclosure include, but are not... information to be withheld. Examples of records exempt from disclosure include, but are not limited to: (i... Federal Government owns or may own a right, title, or interest (including a nonexclusive license), 35 U.S...

77 FR 33133 - Patient Protection and Affordable Care Act; Data Collection To Support Standards Related to...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-05

... includes both quantitative and non-quantitative limits on benefits. Examples of quantitative limits include... duration of treatment. Examples of non-quantitative limits include prior authorization and step therapy... relevant issuers would submit data and descriptive information on the [[Page 33136

15 CFR 700.52 - Examples of assistance.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Examples of assistance. 700.52 Section... DEFENSE PRIORITIES AND ALLOCATIONS SYSTEM Special Priorities Assistance § 700.52 Examples of assistance... an item needed to fill a rated order. (b) Other examples of special priorities assistance include: (1...

26 CFR 1.482-3 - Methods to determine taxable income in connection with a transfer of tangible property.

Code of Federal Regulations, 2010 CFR

2010-04-01

... range. (4) Examples. The principles of this paragraph (b) are illustrated by the following examples..., marketing, advertising programs and services, (including promotional programs, rebates, and co-op... sold and operating expenses. (4) Examples. The following examples illustrate the principles of this...

Mission Driven Scene Understanding: Dynamic Environments

DTIC Science & Technology

2016-06-01

the Army mission. Then, for example, helpful image cues that relate to mission activities may include time of day, current and future weather...mission.10 In other words, visual saliency also can be used to highlight key image cues that relate to Army mission activities.10 For example, an...to the Army mission. Then, for example, helpful image cues that relate to mission activities may include time of day, current and future weather

Pathology Reports

MedlinePlus

... pathology report will include the results of these tests. For example, the pathology report may include information obtained from ... markers or indicators of a specific cancer. For example, the Philadelphia chromosome ... ( 3 ). Some tests that might be performed on a tissue sample ...

26 CFR 1.501(e)-1 - Cooperative hospital service organizations.

Code of Federal Regulations, 2014 CFR

2014-04-01

... illustrated by the following example. Example. An organization performs industrial engineering services on a...-hospitals), warehousing, billing and collection, food, clinical (including radiology), industrial engineering (including the installation, maintenance and repair of biomedical and similar equipment...

26 CFR 1.501(e)-1 - Cooperative hospital service organizations.

Code of Federal Regulations, 2013 CFR

2013-04-01

... illustrated by the following example. Example. An organization performs industrial engineering services on a...-hospitals), warehousing, billing and collection, food, clinical (including radiology), industrial engineering (including the installation, maintenance and repair of biomedical and similar equipment...

26 CFR 1.501(e)-1 - Cooperative hospital service organizations.

Code of Federal Regulations, 2012 CFR

2012-04-01

... illustrated by the following example. Example. An organization performs industrial engineering services on a...-hospitals), warehousing, billing and collection, food, clinical (including radiology), industrial engineering (including the installation, maintenance and repair of biomedical and similar equipment...

26 CFR 1.501(e)-1 - Cooperative hospital service organizations.

Code of Federal Regulations, 2011 CFR

2011-04-01

... illustrated by the following example. Example. An organization performs industrial engineering services on a...-hospitals), warehousing, billing and collection, food, clinical (including radiology), industrial engineering (including the installation, maintenance and repair of biomedical and similar equipment...

26 CFR 1.501(e)-1 - Cooperative hospital service organizations.

Code of Federal Regulations, 2010 CFR

2010-04-01

... illustrated by the following example. Example. An organization performs industrial engineering services on a...-hospitals), warehousing, billing and collection, food, clinical (including radiology), industrial engineering (including the installation, maintenance and repair of biomedical and similar equipment...

Differentiating Instruction: Providing the Right Kinds of Worked Examples for Individual Students

ERIC Educational Resources Information Center

Booth, Julie L.; Koedinger, Kenneth R.; Newton, Kristie J.; Lange, Karin E.

2013-01-01

A plethora of laboratory studies have shown that including the study of worked examples during problem-solving practice improves learning (Sweller, 1999; Sweller & Cooper, 1985). While most worked-example research focuses on the use of correct examples, recent work suggests that asking children to explain a combination of correct and incorrect…

17 CFR 248.120 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-04-01

... marketing communications that are directed at the general public. For example, television, general... particular consumers would not constitute marketing solicitations, even if those communications are intended... communications. (3) Examples of marketing solicitations. A marketing solicitation would include, for example, a...

Industrial Organic Electrosynthesis.

ERIC Educational Resources Information Center

Wagenknecht, John H.

1983-01-01

Four examples of industrial electrochemical synthesis of organic compounds are described. These include acrylonitrile dimerization, tetramethyl lead, electrochemical fluorination, and production of diacetone-2-keto-L-gulonic acid. Additional examples are also cited, including the production of several compounds by the BASF company of Germany. (JN)

Wind energy applications guide

DOE Office of Scientific and Technical Information (OSTI.GOV)

anon.

2001-01-01

The brochure is an introduction to various wind power applications for locations with underdeveloped transmission systems, from remote water pumping to village electrification. It includes an introductory section on wind energy, including wind power basics and system components and then provides examples of applications, including water pumping, stand-alone systems for home and business, systems for community centers, schools, and health clinics, and examples in the industrial area. There is also a page of contacts, plus two specific example applications for a wind-diesel system for a remote station in Antarctica and one on wind-diesel village electrification in Russia.

The Pedagogical Examples of Groups and Rings That Algebraists Think Are Most Important in an Introductory Course

ERIC Educational Resources Information Center

Cook, John Paul; Fukawa-Connelly, Tim

2015-01-01

This article reports on an exploratory study designed to investigate the reasoning behind algebraists' selection of examples. Variation theory provided a lens to analyze their collections of examples. Our findings include the classes of examples of groups and rings that algebraists believe to be most pedagogically useful. Chief among their…

28 CFR 63.6 - Procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... maintenance, and ground water recharge); living resource values (fish and wildlife and biological productivity... example, the following: Public health, safety, and welfare, including water supply, quality, recharge and... include, for example, the following: Depth, velocity and rate of rise of flood water; duration of flooding...

Cantilevered probe detector with piezoelectric element

DOEpatents

Adams, Jesse D; Sulchek, Todd A; Feigin, Stuart C

2014-04-29

A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

Cantilevered probe detector with piezoelectric element

DOEpatents

Adams, Jesse D; Sulchek, Todd A; Feigin, Stuart C

2013-04-30

A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

Cantilevered probe detector with piezoelectric element

DOEpatents

Adams, Jesse D [Reno, NV; Sulchek, Todd A [Oakland, CA; Feigin, Stuart C [Reno, NV

2012-07-10

A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

Cantilevered probe detector with piezoelectric element

DOEpatents

Adams, Jesse D.; Sulchek, Todd A.; Feigin, Stuart C.

2010-04-06

A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

48 CFR 1552.209-74 - Limitation of future contracting.

Code of Federal Regulations, 2014 CFR

2014-10-01

... preclude START contractors from performing construction management services under other EPA contracts. (3... Contracting Officer. Examples of such contracts include, but are not limited to, Superfund Management and... Contracting Officer. Examples of such contracts include, but are not limited to, Superfund Management and...

48 CFR 1552.209-74 - Limitation of future contracting.

Code of Federal Regulations, 2013 CFR

2013-10-01

... preclude START contractors from performing construction management services under other EPA contracts. (3... Contracting Officer. Examples of such contracts include, but are not limited to, Superfund Management and... Contracting Officer. Examples of such contracts include, but are not limited to, Superfund Management and...

47 CFR 68.112 - Hearing aid-compatibility.

Code of Federal Regulations, 2011 CFR

2011-10-01

... workplace common areas. Note to paragraph (b)(1): Examples of workplace common areas include libraries.... Note: Examples of workplace non-common areas include private enclosed offices, open area individual... motel guest rooms, and in any other establishment open to the general public for the purpose of...

47 CFR 68.112 - Hearing aid-compatibility.

Code of Federal Regulations, 2010 CFR

2010-10-01

... workplace common areas. Note to paragraph (b)(1): Examples of workplace common areas include libraries.... Note: Examples of workplace non-common areas include private enclosed offices, open area individual... motel guest rooms, and in any other establishment open to the general public for the purpose of...

32 CFR 32.2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... to vest title in the recipient without further obligation to the Federal Government. An example of..., including design and development of prototypes and processes. The term research also includes activities... used in those parts. For example, “suspension” is defined in this section to mean temporary withdrawal...

TIM Version 3.0 beta Technical Description and User Guide - Appendix B - Example input file for TIMv3.0

EPA Pesticide Factsheets

Terrestrial Investigation Model, TIM, has several appendices to its user guide. This is the appendix that includes an example input file in its preserved format. Both parameters and comments defining them are included.

Deceive, and be deceived!

PubMed

Schuiling, G A

2004-06-01

In their struggle for life, many species, for example prokaryotes, plants and animals, defend themselves by producing substances which may poison or disorientate (potential) enemies (grazers/predators etc), or signal information which puts (potential) enemies on the wrong track. Examples of poisonous/ disorientating substances include prussic acid (e.g. almonds) or morphine (papaver), examples of 'false' visual cues include the appearance of harmless hoverflies which strongly resemble 'dangerous' wasps or certain orchid flowers which resemble the female sex organs of certain insects ('mimicry'). Misleading is an essential part of communication systems.

What Would Buffy Do? The Use of Popular Culture Examples in Undergraduate Library Instruction.

ERIC Educational Resources Information Center

Marshall, Jerilyn

This paper presents results of a survey that gathered information on the use of popular culture examples in college library instruction sessions, including the types of popular culture materials currently being used as examples, the types of courses in which they are used, the librarians' purposes in using the examples, and the librarians'…

77 FR 31894 - Portable Gauge Licenses

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-30

... include safety culture, security of radioactive materials, protection of sensitive information, a revised... draft NUREG and is especially interested in receiving comments on the examples and pictures used in... following questions regarding the examples and pictures in Appendix G: 1. Do the examples for two...

Board of Regents of the Nevada System of Higher Education, on behalf of the University of Nevada, Reno

DOEpatents

Adams, Jesse D.; Sulchek, Todd A.; Feigin, Stuart C.

2017-07-11

A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

26 CFR 48.6420-4 - Meaning of terms.

Code of Federal Regulations, 2013 CFR

2013-04-01

... “poultry” includes chickens, turkeys, geese, ducks, and pigeons. Thus, a farm includes livestock, dairy... operator of the farm in connection with cultivating the soil, raising or harvesting any agricultural or... illustrated by the following example. Example. Farmer A hired custom operator B to cultivate the soil on A's...

26 CFR 48.6420-4 - Meaning of terms.

Code of Federal Regulations, 2011 CFR

2011-04-01

... “poultry” includes chickens, turkeys, geese, ducks, and pigeons. Thus, a farm includes livestock, dairy... operator of the farm in connection with cultivating the soil, raising or harvesting any agricultural or... illustrated by the following example. Example. Farmer A hired custom operator B to cultivate the soil on A's...

26 CFR 48.6420-4 - Meaning of terms.

Code of Federal Regulations, 2012 CFR

2012-04-01

... “poultry” includes chickens, turkeys, geese, ducks, and pigeons. Thus, a farm includes livestock, dairy... operator of the farm in connection with cultivating the soil, raising or harvesting any agricultural or... illustrated by the following example. Example. Farmer A hired custom operator B to cultivate the soil on A's...

76 FR 72678 - Atlantic Highly Migratory Species; Exempted Fishing, Scientific Research, Display, and Chartering...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-25

... from regulation. Examples of research conducted under LOAs include tagging and releasing of sharks... researchers to collect HMS from bona fide research vessels. One example of research conducted under SRPs... require scientists to report their activities associated with these tags. Examples of research conducted...

28 CFR 51.13 - Examples of changes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... THE VOTING RIGHTS ACT OF 1965, AS AMENDED General Provisions § 51.13 Examples of changes. Changes affecting voting include, but are not limited to, the following examples: (a) Any change in qualifications... in the constituency of an official or the boundaries of a voting unit (e.g., through redistricting...

28 CFR 51.13 - Examples of changes.

Code of Federal Regulations, 2011 CFR

2011-07-01

... THE VOTING RIGHTS ACT OF 1965, AS AMENDED General Provisions § 51.13 Examples of changes. Changes affecting voting include, but are not limited to, the following examples: (a) Any change in qualifications... in the constituency of an official or the boundaries of a voting unit (e.g., through redistricting...

21 CFR 1000.15 - Examples of electronic products subject to the Radiation Control for Health and Safety Act of 1968.

Code of Federal Regulations, 2012 CFR

2012-04-01

.... (a) Examples of electronic products which may emit x-rays and other ionizing electromagnetic radiation, electrons, neutrons, and other particulate radiation include: Ionizing electromagnetic radiation... radiation and ionizing electromagnetic radiation: Electron microscopes. Neutron generators. (b) Examples of...

21 CFR 1000.15 - Examples of electronic products subject to the Radiation Control for Health and Safety Act of 1968.

Code of Federal Regulations, 2010 CFR

2010-04-01

.... (a) Examples of electronic products which may emit x-rays and other ionizing electromagnetic radiation, electrons, neutrons, and other particulate radiation include: Ionizing electromagnetic radiation... radiation and ionizing electromagnetic radiation: Electron microscopes. Neutron generators. (b) Examples of...

21 CFR 1000.15 - Examples of electronic products subject to the Radiation Control for Health and Safety Act of 1968.

Code of Federal Regulations, 2011 CFR

2011-04-01

.... (a) Examples of electronic products which may emit x-rays and other ionizing electromagnetic radiation, electrons, neutrons, and other particulate radiation include: Ionizing electromagnetic radiation... radiation and ionizing electromagnetic radiation: Electron microscopes. Neutron generators. (b) Examples of...

21 CFR 1000.15 - Examples of electronic products subject to the Radiation Control for Health and Safety Act of 1968.

Code of Federal Regulations, 2014 CFR

2014-04-01

.... (a) Examples of electronic products which may emit x-rays and other ionizing electromagnetic radiation, electrons, neutrons, and other particulate radiation include: Ionizing electromagnetic radiation... radiation and ionizing electromagnetic radiation: Electron microscopes. Neutron generators. (b) Examples of...

21 CFR 1000.15 - Examples of electronic products subject to the Radiation Control for Health and Safety Act of 1968.

Code of Federal Regulations, 2013 CFR

2013-04-01

.... (a) Examples of electronic products which may emit x-rays and other ionizing electromagnetic radiation, electrons, neutrons, and other particulate radiation include: Ionizing electromagnetic radiation... radiation and ionizing electromagnetic radiation: Electron microscopes. Neutron generators. (b) Examples of...

7 CFR 1710.206 - Approval requirements for load forecasts prepared pursuant to approved load forecast work plans.

Code of Federal Regulations, 2010 CFR

2010-01-01

... narrative shall address the overall approach, time periods, and expected internal and external uses of the forecast. Examples of internal uses include providing information for developing or monitoring demand side... suppliers. Examples of external uses include meeting state and Federal regulatory requirements, obtaining...

Methods for the evaluation of alternative disaster warning systems

NASA Technical Reports Server (NTRS)

Agnew, C. E.; Anderson, R. J., Jr.; Lanen, W. N.

1977-01-01

For each of the methods identified, a theoretical basis is provided and an illustrative example is described. The example includes sufficient realism and detail to enable an analyst to conduct an evaluation of other systems. The methods discussed in the study include equal capability cost analysis, consumers' surplus, and statistical decision theory.

76 FR 64264 - Authority to Require Supervision and Regulation of Certain Nonbank Financial Companies

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-18

... company could pose a threat to the financial stability of the United States, including examples of quantitative metrics for assessing each category; The six uniform quantitative thresholds that the Council..., including examples of the metrics that the Council intends to use when evaluating a nonbank financial...

26 CFR 1.414(s)-1 - Definition of compensation.

Code of Federal Regulations, 2013 CFR

2013-04-01

... will not fail to be defined consistently for a group of employees merely because some employees do not receive one or more of the types of compensation included in the definition. For example, a definition of... some or all of the employer's highly compensated employees (including, for example, any one or more of...

26 CFR 1.414(s)-1 - Definition of compensation.

Code of Federal Regulations, 2014 CFR

2014-04-01

... will not fail to be defined consistently for a group of employees merely because some employees do not receive one or more of the types of compensation included in the definition. For example, a definition of... some or all of the employer's highly compensated employees (including, for example, any one or more of...

26 CFR 1.414(s)-1 - Definition of compensation.

Code of Federal Regulations, 2010 CFR

2010-04-01

... will not fail to be defined consistently for a group of employees merely because some employees do not receive one or more of the types of compensation included in the definition. For example, a definition of... some or all of the employer's highly compensated employees (including, for example, any one or more of...

Alternative Fuels Data Center: States Enact Natural Gas Vehicle and

Science.gov Websites

, conversions, and fueling equipment from their tax liability. Rebates and vouchers are examples of more direct deployment. Recent examples include: Florida's NGV rebates that cover as much as 50% of the incremental cost purchases, research and development projects, or other related activities. For example, the Pennsylvania

78 FR 61227 - Public Assistance Cost Estimating Format for Large Projects

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-03

... itemized breakdown of construction costs for completing the project. For example, a typical project will... percentage factors. For example, if a Part B percentage factor is 2 percent, the estimator adds 2 percent of... specific to the project scope of work. Examples include concrete strength testing, water quality testing...

Teaching Basic Probability in Undergraduate Statistics or Management Science Courses

ERIC Educational Resources Information Center

Naidu, Jaideep T.; Sanford, John F.

2017-01-01

Standard textbooks in core Statistics and Management Science classes present various examples to introduce basic probability concepts to undergraduate business students. These include tossing of a coin, throwing a die, and examples of that nature. While these are good examples to introduce basic probability, we use improvised versions of Russian…

Iteration with Spreadsheets.

ERIC Educational Resources Information Center

Smith, Michael

1990-01-01

Presents several examples of the iteration method using computer spreadsheets. Examples included are simple iterative sequences and the solution of equations using the Newton-Raphson formula, linear interpolation, and interval bisection. (YP)

Energy Lessons by Contract.

ERIC Educational Resources Information Center

Wagganer, John W.

1981-01-01

An elementary activity based energy education unit which utilizes student contracts is described. Examples of the preparation involved, student involvement entailed, and examples of contracts and grading criteria are included. (DS)

The forest health monitoring national technical reports: examples of analyses and results from 2001-2004

Treesearch

Mark J. Ambrose; Barbara L. Conkling; Kurt H. Riitters; John W. Coulston

2008-01-01

This brochure presents examples of analyses included in the first four Forest Health Monitoring (FHM) national technical reports. Its purpose is to introduce the reader to the kinds of information available in these and subsequent FHM national technical reports. Indicators presented here include drought, air pollution, forest fragmentation, and tree mortality. These...

Design software for reuse

NASA Technical Reports Server (NTRS)

Tracz, Will

1990-01-01

Viewgraphs are presented on the designing of software for reuse. Topics include terminology, software reuse maxims, the science of programming, an interface design example, a modularization example, and reuse and implementation guidelines.

Introducing Abelian Groups Using Bullseyes and Jenga

ERIC Educational Resources Information Center

Smith, Michael D.

2016-01-01

The purpose of this article is to share a new approach for introducing students to the definition and standard examples of Abelian groups. The definition of an Abelian group is revised to include six axioms. A bullseye provides a way to visualize elementary examples and non-examples of Abelian groups. An activity based on the game of Jenga is used…

41 CFR 102-5.80 - What are some examples of positions that may involve field work?

Code of Federal Regulations, 2010 CFR

2010-07-01

... of positions that may involve field work? 102-5.80 Section 102-5.80 Public Contracts and Property...-HOME-TO-WORK TRANSPORTATION Authorizing Home-to-Work Transportation § 102-5.80 What are some examples of positions that may involve field work? Examples of positions that may involve field work include...

41 CFR 102-5.80 - What are some examples of positions that may involve field work?

Code of Federal Regulations, 2013 CFR

2013-07-01

... of positions that may involve field work? 102-5.80 Section 102-5.80 Public Contracts and Property...-HOME-TO-WORK TRANSPORTATION Authorizing Home-to-Work Transportation § 102-5.80 What are some examples of positions that may involve field work? Examples of positions that may involve field work include...

41 CFR 102-5.80 - What are some examples of positions that may involve field work?

Code of Federal Regulations, 2012 CFR

2012-01-01

... of positions that may involve field work? 102-5.80 Section 102-5.80 Public Contracts and Property...-HOME-TO-WORK TRANSPORTATION Authorizing Home-to-Work Transportation § 102-5.80 What are some examples of positions that may involve field work? Examples of positions that may involve field work include...

41 CFR 102-5.80 - What are some examples of positions that may involve field work?

Code of Federal Regulations, 2011 CFR

2011-01-01

... of positions that may involve field work? 102-5.80 Section 102-5.80 Public Contracts and Property...-HOME-TO-WORK TRANSPORTATION Authorizing Home-to-Work Transportation § 102-5.80 What are some examples of positions that may involve field work? Examples of positions that may involve field work include...

41 CFR 102-5.80 - What are some examples of positions that may involve field work?

Code of Federal Regulations, 2014 CFR

2014-01-01

... of positions that may involve field work? 102-5.80 Section 102-5.80 Public Contracts and Property...-HOME-TO-WORK TRANSPORTATION Authorizing Home-to-Work Transportation § 102-5.80 What are some examples of positions that may involve field work? Examples of positions that may involve field work include...

Electric field formation in three different plasmas: A fusion reactor, arc discharge, and the ionosphere

NASA Astrophysics Data System (ADS)

Lee, Kwan Chul

2017-11-01

Three examples of electric field formation in the plasma are analyzed based on a new mechanism driven by ion-neutral collisions. The Gyro-Center Shift analysis uses the iteration of three equations including perpendicular current induced by the momentum exchange between ions and neutrals when there is asymmetry over the gyro-motion. This method includes non-zero divergence of current that leads the solution of time dependent state. The first example is radial electric field formation at the boundary of the nuclear fusion device, which is a key factor in the high-confinement mode operation of future fusion reactors. The second example is the reversed rotation of the arc discharge cathode spot, which has been a mysterious subject for more than one hundred years. The third example is electric field formations in the earth's ionosphere, which are important components of the equatorial electrojet and black aurora. The use of one method that explains various examples from different plasmas is reported, along with a discussion of the applications.

Protein Electrophoresis/Immunofixation Electrophoresis

MedlinePlus

... underlying disease. Follow-up tests may include, for example, albumin , immunoelectrophoresis, serum free light chains , quantitative immunoglobuins , ... the disease and the effectiveness of treatment. Some examples of when an electrophoresis test may be ordered ...

Blood Gases Test

MedlinePlus

... a pH, carbon dioxide/oxygen, or electrolyte imbalance. Examples include uncontrolled diabetes , which can lead to ketoacidosis ... acid from the stomach), and sodium bicarbonate overdose. Examples of test results associated with the above conditions ...

NASA/ESMD Analogue Mission Plans

NASA Technical Reports Server (NTRS)

Hoffman, Stephen J.

2007-01-01

A viewgraph presentation exploring Earth and its analogues is shown. The topics include: 1) ESMD Goals for the Use of Earth Analogues; 2) Stakeholders Summary; 3) Issues with Current Analogue Situation; 4) Current state of Analogues; 5) External Implementation Plan (Second Step); 6) Recent Progress in Utilizing Analogues; 7) Website Layout Example-Home Page; 8) Website Layout Example-Analogue Site; 9) Website Layout Example-Analogue Mission; 10) Objectives of ARDIG Analog Initiatives; 11) Future Plans; 12) Example: Cold-Trap Sample Return; 13) Example: Site Characterization Matrix; 14) Integrated Analogue Studies-Prerequisites for Human Exploration; and 15) Rating Scale Definitions.

Focusing on Success: Examples of How the Universal Service Fund Is Helping Improve Connectivity across the Country

ERIC Educational Resources Information Center

Universal Service Administrative Company, 2008

2008-01-01

This report includes examples of how Universal Service Fund support is used by beneficiaries across the country. Included in this version are approximately 140 success stories of how the Universal Service Fund is helping to improve connectivity in the United States. This report is updated quarterly, as Universal Service Administrative Company…

Formal Functional Test Designs: Bridging the Gap Between Test Requirements and Test Specifications

NASA Technical Reports Server (NTRS)

Hops, Jonathan

1993-01-01

This presentation describes the testing life cycle, the purpose of the test design phase, and test design methods and gives an example application. Also included is a description of Test Representation Language (TRL), a summary of the language, and an example of an application of TRL. A sample test requirement and sample test design are included.

A Selection of Composites Simulation Practices at NASA Langley Research Center

NASA Technical Reports Server (NTRS)

Ratcliffe, James G.

2007-01-01

One of the major areas of study at NASA Langley Research Center is the development of technologies that support the use of advanced composite materials in aerospace applications. Amongst the supporting technologies are analysis tools used to simulate the behavior of these materials. This presentation will discuss a number of examples of analysis tools and simulation practices conducted at NASA Langley. The presentation will include examples of damage tolerance analyses for both interlaminar and intralaminar failure modes. Tools for modeling interlaminar failure modes include fracture mechanics and cohesive methods, whilst tools for modeling intralaminar failure involve the development of various progressive failure analyses. Other examples of analyses developed at NASA Langley include a thermo-mechanical model of an orthotropic material and the simulation of delamination growth in z-pin reinforced laminates.

[Depopulation and aging: the example of Gers].

PubMed

Le Gleau, J P; Pradel De Lamaze, F

1980-01-01

The authors examine the process of depopulation and aging in a rural French community using the example of the department of Gers. Some projections of future population trends up to 1985 are included.

Coercive Power of the Federal Purse

ERIC Educational Resources Information Center

Brewster, Kingman

1975-01-01

Cites examples of use of the leverage of the government dollar to manipulate for vindictive or political purposes. Examples include the proposed health manpower legislation and the Family Educational Rights and Privacy Act. (GS)

Bone Marrow Aspiration and Biopsy

MedlinePlus

... point out the need for further investigation. For example, a patient with decreased red blood cells (RBCs) ... and/or staged with this process. A few examples include: Leukemia — cancer of the blood cells Anemia — ...

AFB (Acid-Fast Bacillus) Smear and Culture

MedlinePlus

... area of the body that is affected. Some examples include back pain and paralysis (spinal TB), weakness ... be helpful in deciding what to do. For example, if there is a presumptive diagnosis of TB ...

34 CFR Appendix B to Part 403 - Examples for 34 CFR 403.194-Comparability Requirements

Code of Federal Regulations, 2010 CFR

2010-07-01

... TECHNOLOGY EDUCATION PROGRAM Pt. 403, App. B Appendix B to Part 403—Examples for 34 CFR 403.194—Comparability Requirements Methods by which a local educational agency can demonstrate its compliance with the comparability requirements in 34 CFR 403.194(a) include the following: Example 1: The local educational agency files with the...

Filling temporary underground structures and workings at high-head hydro developments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ilyushin, V.F.

1994-12-01

Examples of backfilling temporary underground structures and workings at hydroelectric stations in Russia are cited. Structures backfilled include temporary tunnels and auxiliary workings (shafts, chambers, etc.). Detail drawings illustrate many of the examples. Examples of backfilling at a number of hydropower plants are given; however, the main emphasis is on construction of Nurek Hydroelectric Station. 8 refs., 11 figs.

Sierra/SolidMechanics 4.46 Example Problems Manual.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Plews, Julia A.; Crane, Nathan K; de Frias, Gabriel Jose

Presented in this document are tests that exist in the Sierra/SolidMechanics example problem suite, which is a subset of the Sierra/SM regression and performance test suite. These examples showcase common and advanced code capabilities. A wide variety of other regression and verification tests exist in the Sierra/SM test suite that are not included in this manual.

PsyToolkit: a software package for programming psychological experiments using Linux.

PubMed

Stoet, Gijsbert

2010-11-01

PsyToolkit is a set of software tools for programming psychological experiments on Linux computers. Given that PsyToolkit is freely available under the Gnu Public License, open source, and designed such that it can easily be modified and extended for individual needs, it is suitable not only for technically oriented Linux users, but also for students, researchers on small budgets, and universities in developing countries. The software includes a high-level scripting language, a library for the programming language C, and a questionnaire presenter. The software easily integrates with other open source tools, such as the statistical software package R. PsyToolkit is designed to work with external hardware (including IoLab and Cedrus response keyboards and two common digital input/output boards) and to support millisecond timing precision. Four in-depth examples explain the basic functionality of PsyToolkit. Example 1 demonstrates a stimulus-response compatibility experiment. Example 2 demonstrates a novel mouse-controlled visual search experiment. Example 3 shows how to control light emitting diodes using PsyToolkit, and Example 4 shows how to build a light-detection sensor. The last two examples explain the electronic hardware setup such that they can even be used with other software packages.

An introduction to scriptwriting for video and multimedia.

PubMed

Guth, J

1995-06-01

The elements of audiovisual productions are explained and illustrated, including words, moving images, still images, graphics, narration, music, landscape sounds, pacing and tilting and font styles. Three different production styles are analysed, and examples of those styles are discussed. Rules for writing spoken words, composing blocks of information, and explaining technical information to a lay audience are also provided. Storyboard and scripting forms and examples are included.

Compositions of doped, co-doped and tri-doped semiconductor materials

DOEpatents

Lynn, Kelvin [Pullman, WA; Jones, Kelly [Colfax, WA; Ciampi, Guido [Watertown, MA

2011-12-06

Semiconductor materials suitable for being used in radiation detectors are disclosed. A particular example of the semiconductor materials includes tellurium, cadmium, and zinc. Tellurium is in molar excess of cadmium and zinc. The example also includes aluminum having a concentration of about 10 to about 20,000 atomic parts per billion and erbium having a concentration of at least 10,000 atomic parts per billion.

An Inexpensive Toroidal Solenoid for an Investigative Student Lab

NASA Astrophysics Data System (ADS)

Ferstl, Andrew; Broberg, John

2008-09-01

Magnetism and Ampère's law is a common subject in most calculus-based introductory physics courses. Many textbooks offer examples to calculate the magnetic field produced by a symmetric current by using Ampère's law. These examples include the solenoid and the toroidal solenoid (sometimes called a torus; see Fig. 1), which are used in many applications, including the study of plasmas.

Exometabolomics Assisted Design and Validation of Synthetic Obligate Mutualism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kosina, Suzanne M.; Danielewicz, Megan A.; Mohammed, Mujahid

Synthetic microbial ecology has the potential to enhance the productivity and resiliency of biotechnology processes compared to approaches using single isolates. Engineering microbial consortia is challenging; however, one approach that has attracted significant attention is the creation of synthetic obligate mutualism using auxotrophic mutants that depend on each other for exchange or cross-feeding of metabolites. In this paper, we describe the integration of mutant library fitness profiling with mass spectrometry based exometabolomics as a method for constructing synthetic mutualism based on cross-feeding. Two industrially important species lacking known ecological interactions, Zymomonas mobilis and Escherichia coli, were selected as the testmore » species. Amino acid exometabolites identified in the spent medium of Z. mobilis were used to select three corresponding E. coli auxotrophs (proA, pheA and IlvA), as potential E. coli counterparts for the coculture. A pooled mutant fitness assay with a Z. mobilis transposon mutant library was used to identify mutants with improved growth in the presence of E. coli. An auxotroph mutant in a gene (ZMO0748) with sequence similarity to cysteine synthase A (cysK), was selected as the Z. mobilis counterpart for the coculture. Exometabolomic analysis of spent E. coli medium identified glutathione related metabolites as potentially available for rescue of the Z. mobilis cysteine synthase mutant. Three sets of cocultures between the Z. mobilis auxotroph and each of the three E. coli auxotrophs were monitored by optical density for growth and analyzed by flow cytometry to confirm high cell counts for each species. Taken together, our methods provide a technological framework for creating synthetic mutualisms combining existing screening based methods and exometabolomics for both the selection of obligate mutualism partners and elucidation of metabolites involved in auxotroph rescue.« less

Enhancement of expression and apparent secretion of Erwinia chrysanthemi endoglucanase (encoded by celZ) in Escherichia coli B

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, S.; Yomano, L.P.; Saleh, A.Z.

1999-06-01

Escherichia coli B has been engineered as a biocatalyst for the conversion of lignocellulose into ethanol. Previous research has demonstrated that derivatives of E. coli B can produce high levels of Erwinia chrysanthemi endoglucanase (encoded by celZ) as a periplasmic product and that this enzyme can function with commercial fungal cellulase to increase ethanol production. In this study, the authors have demonstrated two methods that improve celZ expression in E. coli B. Initially, with a low-copy-number vector, two E. coli glycolytic gene promoters (gap and eno) were tested and found to be less effective than the original celZ promoter. Bymore » screening 18,000 random fragments of Zymomonas mobilis DNA, a surrogate promoter was identified which increased celZ expression up to sixfold. With this promoter, large polar inclusion bodies were clearly evident in the periplasmic space. Sequencing revealed that the most active surrogate promoter is derived from five Sau3A1 fragments, one of which was previously sequenced in Z. mobilis. Visual inspection indicated that this DNA fragment contains at least five putative promoter regions, two of which were confirmed by primer extension analysis. Addition of the out genes from E. chrysanthemi EC16 caused a further increase in the production of active enzyme and facilitated secretion or release of over half of the activity into the extracellular environment. With the most active construct, of a total of 13,000 IU of active enzyme per liter of culture, 7,800 IU was in the supernatant. The total active endoglucanase was estimated to represent 4 to 6% of cellular protein.« less

Sucrose dependent mineral phosphate solubilization in Enterobacter asburiae PSI3 by heterologous overexpression of periplasmic invertases.

PubMed

Kumar, Chanchal; Wagh, Jitendra; Archana, G; Naresh Kumar, G

2016-12-01

Enterobacter asburiae PSI3 solubilizes mineral phosphates in the presence of glucose by the secretion of gluconic acid generated by the action of a periplasmic pyrroloquinoline quinone dependent glucose dehydrogenase. In order to achieve mineral phosphate solubilization phenotype in the presence of sucrose, plasmids pCNK4 and pCNK5 containing genes encoding the invertase enzyme of Zymomonas mobilis (invB) and of Saccharomyces cerevisiae (suc2) under constitutive promoters were constructed with malE signal sequence (in case of invB alone as the suc2 is secreted natively). When introduced into E. asburiae PSI3, E. a. (pCNK4) and E. a. (pCNK5) transformants secreted 21.65 ± 0.94 and 22 ± 1.3 mM gluconic acid, respectively, in the presence of 75 mM sucrose and they also solubilized 180 ± 4.3 and 438 ± 7.3 µM P from the rock phosphate. In the presence of a mixture of 50 mM sucrose and 25 mM glucose, E. a. (pCNK5) secreted 34 ± 2.3 mM gluconic acid and released 479 ± 8.1 µM P. Moreover, in the presence of a mixture of eight sugars (10 mM each) in the medium, E. a. (pCNK5) released 414 ± 5.3 µM P in the buffered medium. Thus, this study demonstrates incorporation of periplasmic invertase imparted P solubilization ability to E. asburiae PSI3 in the presence of sucrose and mixture of sugars.

Genetic engineering of Clostridium thermocellum DSM1313 for enhanced ethanol production.

PubMed

Kannuchamy, Saranyah; Mukund, Nisha; Saleena, Lilly M

2016-05-11

The twin problem of shortage in fossil fuel and increase in environmental pollution can be partly addressed by blending of ethanol with transport fuel. Increasing the ethanol production for this purpose without affecting the food security of the countries would require the use of cellulosic plant materials as substrate. Clostridium thermocellum is an anaerobic thermophilic bacterium with cellulolytic property and the ability to produce ethanol. But its application as biocatalyst for ethanol production is limited because pyruvate ferredoxin oxidoreductase, which diverts pyruvate to ethanol production pathway, has low affinity to the substrate. Therefore, the present study was undertaken to genetically modify C. thermocellum for enhancing its ethanol production capacity by transferring pyruvate carboxylase (pdc) and alcohol dehydrogenase (adh) genes of the homoethanol pathway from Zymomonas mobilis. The pdc and adh genes from Z. mobilis were cloned in pNW33N, and transformed to Clostridium thermocellum DSM 1313 by electroporation to generate recombinant CTH-pdc, CTH-adh and CTH-pdc-adh strains that carried heterologous pdc, adh, and both genes, respectively. The plasmids were stably maintained in the recombinant strains. Though both pdc and adh were functional in C. thermocellum, the presence of adh severely limited the growth of the recombinant strains, irrespective of the presence or absence of the pdc gene. The recombinant CTH-pdc strain showed two-fold increase in pyruvate carboxylase activity and ethanol production when compared with the wild type strain. Pyruvate decarboxylase gene of the homoethanol pathway from Z mobilis was functional in recombinant C. thermocellum strain and enhanced its ability to produced ethanol. Strain improvement and bioprocess optimizations may further increase the ethanol production from this recombinant strain.

OptSSeq: High-throughput sequencing readout of growth enrichment defines optimal gene expression elements for homoethanologenesis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghosh, Indro Neil; Landick, Robert

The optimization of synthetic pathways is a central challenge in metabolic engineering. OptSSeq (Optimization by Selection and Sequencing) is one approach to this challenge. OptSSeq couples selection of optimal enzyme expression levels linked to cell growth rate with high-throughput sequencing to track enrichment of gene expression elements (promoters and ribosomebinding sites) from a combinatorial library. OptSSeq yields information on both optimal and suboptimal enzyme levels, and helps identify constraints that limit maximal product formation. Here we report a proof-of-concept implementation of OptSSeq using homoethanologenesis, a two-step pathway consisting of pyruvate decarboxylase (Pdc) and alcohol dehydrogenase (Adh) that converts pyruvate tomore » ethanol and is naturally optimized in the bacterium Zymomonas mobilis. We used OptSSeq to determine optimal gene expression elements and enzyme levels for Z. mobilis Pdc, AdhA, and AdhB expressed in Escherichia coli. By varying both expression signals and gene order, we identified an optimal solution using only Pdc and AdhB. We resolved current uncertainty about the functions of the Fe 2+-dependent AdhB and Zn 2+- dependent AdhA by showing that AdhB is preferred over AdhA for rapid growth in both E. coli and Z. mobilis. Finally, by comparing predictions of growth-linked metabolic flux to enzyme synthesis costs, we established that optimal E. coli homoethanologenesis was achieved by our best pdc-adhB expression cassette and that the remaining constraints lie in the E. coli metabolic network or inefficient Pdc or AdhB function in E. coli. Furthermore, OptSSeq is a general tool for synthetic biology to tune enzyme levels in any pathway whose optimal function can be linked to cell growth or survival.« less

Increase in Furfural Tolerance in Ethanologenic Escherichia coli LY180 by Plasmid-Based Expression of thyA

PubMed Central

Zheng, Huabao; Wang, Xuan; Yomano, Lorraine P.; Shanmugam, Keelnatham T.

2012-01-01

Furfural is an inhibitory side product formed during the depolymerization of hemicellulose by mineral acids. Genomic libraries from three different bacteria (Bacillus subtilis YB886, Escherichia coli NC3, and Zymomonas mobilis CP4) were screened for genes that conferred furfural resistance on plates. Beneficial plasmids containing the thyA gene (coding for thymidylate synthase) were recovered from all three organisms. Expression of this key gene in the de novo pathway for dTMP biosynthesis improved furfural resistance on plates and during fermentation. A similar benefit was observed by supplementation with thymine, thymidine, or the combination of tetrahydrofolate and serine (precursors for 5,10-methylenetetrahydrofolate, the methyl donor for ThyA). Supplementation with deoxyuridine provided a small benefit, and deoxyribose was of no benefit for furfural tolerance. A combination of thymidine and plasmid expression of thyA was no more effective than either alone. Together, these results demonstrate that furfural tolerance is increased by approaches that increase the supply of pyrimidine deoxyribonucleotides. However, ThyA activity was not directly affected by the addition of furfural. Furfural has been previously shown to damage DNA in E. coli and to activate a cellular response to oxidative damage in yeast. The added burden of repairing furfural-damaged DNA in E. coli would be expected to increase the cellular requirement for dTMP. Increased expression of thyA (E. coli, B. subtilis, or Z. mobilis), supplementation of cultures with thymidine, and supplementation with precursors for 5,10-methylenetetrahydrofolate (methyl donor) are each proposed to increase furfural tolerance by increasing the availability of dTMP for DNA repair. PMID:22504824

Increase in furfural tolerance in ethanologenic Escherichia coli LY180 by plasmid-based expression of thyA.

PubMed

Zheng, Huabao; Wang, Xuan; Yomano, Lorraine P; Shanmugam, Keelnatham T; Ingram, Lonnie O

2012-06-01

Furfural is an inhibitory side product formed during the depolymerization of hemicellulose by mineral acids. Genomic libraries from three different bacteria (Bacillus subtilis YB886, Escherichia coli NC3, and Zymomonas mobilis CP4) were screened for genes that conferred furfural resistance on plates. Beneficial plasmids containing the thyA gene (coding for thymidylate synthase) were recovered from all three organisms. Expression of this key gene in the de novo pathway for dTMP biosynthesis improved furfural resistance on plates and during fermentation. A similar benefit was observed by supplementation with thymine, thymidine, or the combination of tetrahydrofolate and serine (precursors for 5,10-methylenetetrahydrofolate, the methyl donor for ThyA). Supplementation with deoxyuridine provided a small benefit, and deoxyribose was of no benefit for furfural tolerance. A combination of thymidine and plasmid expression of thyA was no more effective than either alone. Together, these results demonstrate that furfural tolerance is increased by approaches that increase the supply of pyrimidine deoxyribonucleotides. However, ThyA activity was not directly affected by the addition of furfural. Furfural has been previously shown to damage DNA in E. coli and to activate a cellular response to oxidative damage in yeast. The added burden of repairing furfural-damaged DNA in E. coli would be expected to increase the cellular requirement for dTMP. Increased expression of thyA (E. coli, B. subtilis, or Z. mobilis), supplementation of cultures with thymidine, and supplementation with precursors for 5,10-methylenetetrahydrofolate (methyl donor) are each proposed to increase furfural tolerance by increasing the availability of dTMP for DNA repair.

Exometabolomics Assisted Design and Validation of Synthetic Obligate Mutualism

DOE PAGES

Kosina, Suzanne M.; Danielewicz, Megan A.; Mohammed, Mujahid; ...

2016-02-17

Synthetic microbial ecology has the potential to enhance the productivity and resiliency of biotechnology processes compared to approaches using single isolates. Engineering microbial consortia is challenging; however, one approach that has attracted significant attention is the creation of synthetic obligate mutualism using auxotrophic mutants that depend on each other for exchange or cross-feeding of metabolites. In this paper, we describe the integration of mutant library fitness profiling with mass spectrometry based exometabolomics as a method for constructing synthetic mutualism based on cross-feeding. Two industrially important species lacking known ecological interactions, Zymomonas mobilis and Escherichia coli, were selected as the testmore » species. Amino acid exometabolites identified in the spent medium of Z. mobilis were used to select three corresponding E. coli auxotrophs (proA, pheA and IlvA), as potential E. coli counterparts for the coculture. A pooled mutant fitness assay with a Z. mobilis transposon mutant library was used to identify mutants with improved growth in the presence of E. coli. An auxotroph mutant in a gene (ZMO0748) with sequence similarity to cysteine synthase A (cysK), was selected as the Z. mobilis counterpart for the coculture. Exometabolomic analysis of spent E. coli medium identified glutathione related metabolites as potentially available for rescue of the Z. mobilis cysteine synthase mutant. Three sets of cocultures between the Z. mobilis auxotroph and each of the three E. coli auxotrophs were monitored by optical density for growth and analyzed by flow cytometry to confirm high cell counts for each species. Taken together, our methods provide a technological framework for creating synthetic mutualisms combining existing screening based methods and exometabolomics for both the selection of obligate mutualism partners and elucidation of metabolites involved in auxotroph rescue.« less

OptSSeq: High-throughput sequencing readout of growth enrichment defines optimal gene expression elements for homoethanologenesis

DOE PAGES

Ghosh, Indro Neil; Landick, Robert

2016-07-16

The optimization of synthetic pathways is a central challenge in metabolic engineering. OptSSeq (Optimization by Selection and Sequencing) is one approach to this challenge. OptSSeq couples selection of optimal enzyme expression levels linked to cell growth rate with high-throughput sequencing to track enrichment of gene expression elements (promoters and ribosomebinding sites) from a combinatorial library. OptSSeq yields information on both optimal and suboptimal enzyme levels, and helps identify constraints that limit maximal product formation. Here we report a proof-of-concept implementation of OptSSeq using homoethanologenesis, a two-step pathway consisting of pyruvate decarboxylase (Pdc) and alcohol dehydrogenase (Adh) that converts pyruvate tomore » ethanol and is naturally optimized in the bacterium Zymomonas mobilis. We used OptSSeq to determine optimal gene expression elements and enzyme levels for Z. mobilis Pdc, AdhA, and AdhB expressed in Escherichia coli. By varying both expression signals and gene order, we identified an optimal solution using only Pdc and AdhB. We resolved current uncertainty about the functions of the Fe 2+-dependent AdhB and Zn 2+- dependent AdhA by showing that AdhB is preferred over AdhA for rapid growth in both E. coli and Z. mobilis. Finally, by comparing predictions of growth-linked metabolic flux to enzyme synthesis costs, we established that optimal E. coli homoethanologenesis was achieved by our best pdc-adhB expression cassette and that the remaining constraints lie in the E. coli metabolic network or inefficient Pdc or AdhB function in E. coli. Furthermore, OptSSeq is a general tool for synthetic biology to tune enzyme levels in any pathway whose optimal function can be linked to cell growth or survival.« less

Exometabolomics Assisted Design and Validation of Synthetic Obligate Mutualism.

PubMed

Kosina, Suzanne M; Danielewicz, Megan A; Mohammed, Mujahid; Ray, Jayashree; Suh, Yumi; Yilmaz, Suzan; Singh, Anup K; Arkin, Adam P; Deutschbauer, Adam M; Northen, Trent R

2016-07-15

Synthetic microbial ecology has the potential to enhance the productivity and resiliency of biotechnology processes compared to approaches using single isolates. Engineering microbial consortia is challenging; however, one approach that has attracted significant attention is the creation of synthetic obligate mutualism using auxotrophic mutants that depend on each other for exchange or cross-feeding of metabolites. Here, we describe the integration of mutant library fitness profiling with mass spectrometry based exometabolomics as a method for constructing synthetic mutualism based on cross-feeding. Two industrially important species lacking known ecological interactions, Zymomonas mobilis and Escherichia coli, were selected as the test species. Amino acid exometabolites identified in the spent medium of Z. mobilis were used to select three corresponding E. coli auxotrophs (proA, pheA and IlvA), as potential E. coli counterparts for the coculture. A pooled mutant fitness assay with a Z. mobilis transposon mutant library was used to identify mutants with improved growth in the presence of E. coli. An auxotroph mutant in a gene (ZMO0748) with sequence similarity to cysteine synthase A (cysK), was selected as the Z. mobilis counterpart for the coculture. Exometabolomic analysis of spent E. coli medium identified glutathione related metabolites as potentially available for rescue of the Z. mobilis cysteine synthase mutant. Three sets of cocultures between the Z. mobilis auxotroph and each of the three E. coli auxotrophs were monitored by optical density for growth and analyzed by flow cytometry to confirm high cell counts for each species. Taken together, our methods provide a technological framework for creating synthetic mutualisms combining existing screening based methods and exometabolomics for both the selection of obligate mutualism partners and elucidation of metabolites involved in auxotroph rescue.

The Difference Equation xn=axn-1+b.

ERIC Educational Resources Information Center

Spence, Lawrence E.

1990-01-01

Applications of generalizations of both arithmetic and geometric progressions are presented. The first-order difference equation is used in solving seven examples from finance, business, and medicine. Detailed directions are included for each example. (KR)

Energy and Environment Guide to Action - Chapter 4.5: Lead by Example

EPA Pesticide Factsheets

Provides recommendations on designing, implementing, and evaluating lead by example programs, which offer states opportunities to achieve substantial energy cost savings within their operations. State success stories are included for reference.

The Extraterrestrial Materials Simulation Laboratory

NASA Technical Reports Server (NTRS)

Green, J. R.

2001-01-01

In contrast to fly-by and orbital missions, in situ missions face an incredible array of challenges in near-target navigation, landing site selection, descent, landing, science operations, sample collection and handling, drilling, anchoring, subsurface descent, communications, and contamination. The wide range of materials characteristics and environments threaten mission safety and success. For example, many physical properties are poorly characterized, including strength, composition, heterogeneity, phase change, texture, thermal properties, terrain features, atmospheric interaction, and stratigraphy. Examples of the range of materials properties include, for example: (1) Comets, with a possible compressive strength ranging from a light fluff to harder than concrete: 10(exp 2) to 10 (exp 8) Pa; (2) Europa, including a possible phase change at the surface, unknown strength and terrain roughness; and (3) Titan, with a completely unknown surface and possible liquid ocean. Additional information is contained in the original extended abstract.

Reference Model for Project Support Environments Version 1.0

DTIC Science & Technology

1993-02-28

relationship with the framework’s Process Support services and with the Lifecycle Process Engineering services. Examples: "* ORCA (Object-based...Design services. Examples: "* ORCA (Object-based Requirements Capture and Analysis). "* RETRAC (REquirements TRACeability). 4.3 Life-Cycle Process...34traditional" computer tools. Operations: Examples of audio and video processing operations include: "* Create, modify, and delete sound and video data

25 CFR 309.15 - What are examples of apparel that are Indian products?

Code of Federal Regulations, 2013 CFR

2013-04-01

... products. (b) Specific examples include, but are not limited to: seal skin parkas, ribbon appliqué dance shawls, smoked moose hide slippers, deer skin boots, patchwork jackets, calico ribbon shirts, wing...

25 CFR 309.15 - What are examples of apparel that are Indian products?

Code of Federal Regulations, 2012 CFR

2012-04-01

... products. (b) Specific examples include, but are not limited to: seal skin parkas, ribbon appliqué dance shawls, smoked moose hide slippers, deer skin boots, patchwork jackets, calico ribbon shirts, wing...

25 CFR 309.15 - What are examples of apparel that are Indian products?

Code of Federal Regulations, 2014 CFR

2014-04-01

... products. (b) Specific examples include, but are not limited to: seal skin parkas, ribbon appliqué dance shawls, smoked moose hide slippers, deer skin boots, patchwork jackets, calico ribbon shirts, wing...

15 CFR 710.4 - Overview of scheduled chemicals and examples of affected industries.

Code of Federal Regulations, 2013 CFR

2013-01-01

... provides examples of the types of industries that may be affected by the CWCR (parts 710 through 729 of...) Batteries; (vi) Cyanic acid; (vii) Toiletries, including perfumes and scents; (viii) Organic phosphate...

15 CFR 710.4 - Overview of scheduled chemicals and examples of affected industries.

Code of Federal Regulations, 2011 CFR

2011-01-01

... provides examples of the types of industries that may be affected by the CWCR (parts 710 through 729 of...) Batteries; (vi) Cyanic acid; (vii) Toiletries, including perfumes and scents; (viii) Organic phosphate...

Finding ergonomic solutions--participatory approaches.

PubMed

Hignett, Sue; Wilson, John R; Morris, Wendy

2005-05-01

This paper gives an overview of the theory of participatory ergonomics interventions and summary examples from a range of industries, including health care, military, manufacturing, production and processing, services, construction and transport. The definition of participatory approaches includes interventions at macro (organizational, systems) levels as well as micro (individual), where workers are given the opportunity and power to use their knowledge to address ergonomic problems relating to their own working activities. Examples are given where a cost-effective benefit has been measured using musculoskeletal sickness absence and compensation costs. Other examples, using different outcome measures, also showed improvements, for example, an increase in productivity, improved communication between staff and management, reduction in risk factors, the development of new processes and new designs for work environments and activities. Three cases are described from Canada and Japan where the participatory project was led by occupational health teams, suggesting that occupational health practitioners can have an important role to play in participatory ergonomics projects.

Analysis of bacterial community during the fermentation of pulque, a traditional Mexican alcoholic beverage, using a polyphasic approach.

PubMed

Escalante, Adelfo; Giles-Gómez, Martha; Hernández, Georgina; Córdova-Aguilar, María Soledad; López-Munguía, Agustín; Gosset, Guillermo; Bolívar, Francisco

2008-05-31

In this study, the characterization of the bacterial community present during the fermentation of pulque, a traditional Mexican alcoholic beverage from maguey (Agave), was determined for the first time by a polyphasic approach in which both culture and non-culture dependent methods were utilized. The work included the isolation of lactic acid bacteria (LAB), aerobic mesophiles, and 16S rDNA clone libraries from total DNA extracted from the maguey sap (aguamiel) used as substrate, after inoculation with a sample of previously produced pulque and followed by 6-h fermentation. Microbiological diversity results were correlated with fermentation process parameters such as sucrose, glucose, fructose and fermentation product concentrations. In addition, medium rheological behavior analysis and scanning electron microscopy in aguamiel and during pulque fermentation were also performed. Our results showed that both culture and non-culture dependent approaches allowed the detection of several new and previously reported species within the alpha-, gamma-Proteobacteria and Firmicutes. Bacteria diversity in aguamiel was composed by the heterofermentative Leuconostoc citreum, L. mesenteroides, L. kimchi, the gamma-Proteobacteria Erwinia rhapontici, Enterobacter spp. and Acinetobacter radioresistens. Inoculation with previously fermented pulque incorporated to the system microbiota, homofermentative lactobacilli related to Lactobacillus acidophilus, several alpha-Proteobacteria such as Zymomonas mobilis and Acetobacter malorum, other gamma-Proteobacteria and an important amount of yeasts, creating a starting metabolic diversity composed by homofermentative and heterofermentative LAB, acetic and ethanol producing microorganisms. At the end of the fermentation process, the bacterial diversity was mainly composed by the homofermentative Lactobacillus acidophilus, the heterofermentative L. mesenteroides, Lactococcus lactis subsp. lactis and the alpha-Proteobacteria A. malorum. After a 6-h fermentation, 83.27% of total sugars detected after inoculation were consumed (228.4 mM hexose equivalents) and a carbon (C) recovery of 66.18% in fermentation products was estimated. They were produced 284.4 mM C as ethanol, 71.5 mM C as acetic acid and 19 mM C as lactic acid, demonstrating the presence of homo- and heterofermentative, acetic and alcoholic metabolisms in the final product. It was also found, after hydrolysis, that the exopolysaccharide produced during the fermentation was mainly composed by fructose residues, probably inulin or levan.

A novel cost-effective technology to convert sucrose and homocelluloses in sweet sorghum stalks into ethanol.

PubMed

Li, Jihong; Li, Shizhong; Han, Bing; Yu, Menghui; Li, Guangming; Jiang, Yan

2013-11-29

Sweet sorghum is regarded as a very promising energy crop for ethanol production because it not only supplies grain and sugar, but also offers lignocellulosic resource. Cost-competitive ethanol production requires bioconversion of all carbohydrates in stalks including of both sucrose and lignocellulose hydrolyzed into fermentable sugars. However, it is still a main challenge to reduce ethanol production cost and improve feasibility of industrial application. An integration of the different operations within the whole process is a potential solution. An integrated process combined advanced solid-state fermentation technology (ASSF) and alkaline pretreatment was presented in this work. Soluble sugars in sweet sorghum stalks were firstly converted into ethanol by ASSF using crushed stalks directly. Then, the operation combining ethanol distillation and alkaline pretreatment was performed in one distillation-reactor simultaneously. The corresponding investigation indicated that the addition of alkali did not affect the ethanol recovery. The effect of three alkalis, NaOH, KOH and Ca(OH)2 on pretreatment were investigated. The results indicated the delignification of lignocellulose by NaOH and KOH was more significant than that by Ca(OH)2, and the highest removal of xylan was caused by NaOH. Moreover, an optimized alkali loading of 10% (w/w DM) NaOH was determined. Under this favorable pretreatment condition, enzymatic hydrolysis of sweet sorghum bagasse following pretreatment was investigated. 92.0% of glucan and 53.3% of xylan conversion were obtained at enzyme loading of 10 FPU/g glucan. The fermentation of hydrolyzed slurry was performed using an engineered stain, Zymomonas mobilis TSH-01. A mass balance of the overall process was calculated, and 91.9 kg was achieved from one tonne of fresh sweet sorghum stalk. A low energy-consumption integrated technology for ethanol production from sweet sorghum stalks was presented in this work. Energy consumption for raw materials preparation and pretreatment were reduced or avoided in our process. Based on this technology, the recalcitrance of lignocellulose was destructed via a cost-efficient process and all sugars in sweet sorghum stalks lignocellulose were hydrolysed into fermentable sugars. Bioconversion of fermentable sugars released from sweet sorghum bagasse into different products except ethanol, such as butanol, biogas, and chemicals was feasible to operate under low energy-consumption conditions.

Metabolic engineering of a tyrosine-overproducing yeast platform using targeted metabolomics.

PubMed

Gold, Nicholas D; Gowen, Christopher M; Lussier, Francois-Xavier; Cautha, Sarat C; Mahadevan, Radhakrishnan; Martin, Vincent J J

2015-05-28

L-tyrosine is a common precursor for a wide range of valuable secondary metabolites, including benzylisoquinoline alkaloids (BIAs) and many polyketides. An industrially tractable yeast strain optimized for production of L-tyrosine could serve as a platform for the development of BIA and polyketide cell factories. This study applied a targeted metabolomics approach to evaluate metabolic engineering strategies to increase the availability of intracellular L-tyrosine in the yeast Saccharomyces cerevisiae CEN.PK. Our engineering strategies combined localized pathway engineering with global engineering of central metabolism, facilitated by genome-scale steady-state modelling. Addition of a tyrosine feedback resistant version of 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase Aro4 from S. cerevisiae was combined with overexpression of either a tyrosine feedback resistant yeast chorismate mutase Aro7, the native pentafunctional arom protein Aro1, native prephenate dehydrogenase Tyr1 or cyclohexadienyl dehydrogenase TyrC from Zymomonas mobilis. Loss of aromatic carbon was limited by eliminating phenylpyruvate decarboxylase Aro10. The TAL gene from Rhodobacter sphaeroides was used to produce coumarate as a simple test case of a heterologous by-product of tyrosine. Additionally, multiple strategies for engineering global metabolism to promote tyrosine production were evaluated using metabolic modelling. The T21E mutant of pyruvate kinase Cdc19 was hypothesized to slow the conversion of phosphoenolpyruvate to pyruvate and accumulate the former as precursor to the shikimate pathway. The ZWF1 gene coding for glucose-6-phosphate dehydrogenase was deleted to create an NADPH deficiency designed to force the cell to couple its growth to tyrosine production via overexpressed NADP(+)-dependent prephenate dehydrogenase Tyr1. Our engineered Zwf1(-) strain expressing TYRC ARO4(FBR) and grown in the presence of methionine achieved an intracellular L-tyrosine accumulation up to 520 μmol/g DCW or 192 mM in the cytosol, but sustained flux through this pathway was found to depend on the complete elimination of feedback inhibition and degradation pathways. Our targeted metabolomics approach confirmed a likely regulatory site at DAHP synthase and identified another possible cofactor limitation at prephenate dehydrogenase. Additionally, the genome-scale metabolic model identified design strategies that have the potential to improve availability of erythrose 4-phosphate for DAHP synthase and cofactor availability for prephenate dehydrogenase. We evaluated these strategies and provide recommendations for further improvement of aromatic amino acid biosynthesis in S. cerevisiae.

A novel cost-effective technology to convert sucrose and homocelluloses in sweet sorghum stalks into ethanol

PubMed Central

2013-01-01

Background Sweet sorghum is regarded as a very promising energy crop for ethanol production because it not only supplies grain and sugar, but also offers lignocellulosic resource. Cost-competitive ethanol production requires bioconversion of all carbohydrates in stalks including of both sucrose and lignocellulose hydrolyzed into fermentable sugars. However, it is still a main challenge to reduce ethanol production cost and improve feasibility of industrial application. An integration of the different operations within the whole process is a potential solution. Results An integrated process combined advanced solid-state fermentation technology (ASSF) and alkaline pretreatment was presented in this work. Soluble sugars in sweet sorghum stalks were firstly converted into ethanol by ASSF using crushed stalks directly. Then, the operation combining ethanol distillation and alkaline pretreatment was performed in one distillation-reactor simultaneously. The corresponding investigation indicated that the addition of alkali did not affect the ethanol recovery. The effect of three alkalis, NaOH, KOH and Ca(OH)2 on pretreatment were investigated. The results indicated the delignification of lignocellulose by NaOH and KOH was more significant than that by Ca(OH)2, and the highest removal of xylan was caused by NaOH. Moreover, an optimized alkali loading of 10% (w/w DM) NaOH was determined. Under this favorable pretreatment condition, enzymatic hydrolysis of sweet sorghum bagasse following pretreatment was investigated. 92.0% of glucan and 53.3% of xylan conversion were obtained at enzyme loading of 10 FPU/g glucan. The fermentation of hydrolyzed slurry was performed using an engineered stain, Zymomonas mobilis TSH-01. A mass balance of the overall process was calculated, and 91.9 kg was achieved from one tonne of fresh sweet sorghum stalk. Conclusions A low energy-consumption integrated technology for ethanol production from sweet sorghum stalks was presented in this work. Energy consumption for raw materials preparation and pretreatment were reduced or avoided in our process. Based on this technology, the recalcitrance of lignocellulose was destructed via a cost-efficient process and all sugars in sweet sorghum stalks lignocellulose were hydrolysed into fermentable sugars. Bioconversion of fermentable sugars released from sweet sorghum bagasse into different products except ethanol, such as butanol, biogas, and chemicals was feasible to operate under low energy-consumption conditions. PMID:24286508

Cellular Automata with Anticipation: Examples and Presumable Applications

NASA Astrophysics Data System (ADS)

Krushinsky, Dmitry; Makarenko, Alexander

2010-11-01

One of the most prospective new methodologies for modelling is the so-called cellular automata (CA) approach. According to this paradigm, the models are built from simple elements connected into regular structures with local interaction between neighbours. The patterns of connections usually have a simple geometry (lattices). As one of the classical examples of CA we mention the game `Life' by J. Conway. This paper presents two examples of CA with anticipation property. These examples include a modification of the game `Life' and a cellular model of crowd movement.

Designing for fiber composite structural durability in hygrothermomechanical environment

NASA Technical Reports Server (NTRS)

Chamis, C. C.

1985-01-01

A methodology is described which can be used to design/analyze fiber composite structures subjected to complex hygrothermomechanical environments. This methodology includes composite mechanics and advanced structural analysis methods (finite element). Select examples are described to illustrate the application of the available methodology. The examples include: (1) composite progressive fracture; (2) composite design for high cycle fatigue combined with hot-wet conditions; and (3) general laminate design.

Inducing Ontologies from Folksonomies using Natural Language Understanding

DTIC Science & Technology

2009-11-13

3000, Richardson, TX, 75080 Phone number: (972) 680-0800 Effective date of contract: April 28th, 2009 Short title of work: Contract expiration date...highly correlated tags. Non-trivial examples include: EQUALITY(acr/vzYy, activities), EQUALITY {after- effects , AfterEffects), and EQUALITY(opz’w’ott...This procedure added 23.66% of the total number of relations to the ontology. Examples include lSA( vegan , vegetarian), ANTONYMY (peace, war

An overview of some monoplanar missile programs

NASA Technical Reports Server (NTRS)

Spearman, M. L.

1984-01-01

A historical review is presented of some monoplanar missile systems in which the vehicle flight control was similar to that for a conventional aircraft. The review is essentially chronological, beginning prior to World War I, and includes worldwise programs. Illustrative examples of aerodynamic research with monoplanar missiles are presented including some comparisons with cruciform missiles. Some examples of current programs are presented and some particular mission applications for monoplanar systems are discussed.

Turkey: a pilot study of elder mistreatment in a convenience sample.

PubMed

Yalçinkaya, Alev; Mandiracioğlu, Aliye; Turan, Feryal

2006-01-01

Attitudes towards elder abuse were explored through a survey on International Perspectives on Family Violence and Abuse in a Turkish convenience sample of 25 females and 14 males, ranging in age from 22 to 58. Participants gave examples of behaviors considered in their culture to be extremely abusive, moderately abusive, and mildly abusive from an adult child toward his or her older parent. Responses were coded into four major categories of abuse, each of which had several subcategories: psychological aggression (including the subcategories of verbal aggression, emotional abuse, disrespect, disobedience, power assertion, blame, and imprisonment), neglect (including physical neglect, psychological neglect, abandonment, and putting the older individual into a nursing home), physical aggression (including beating and hitting), and mistreatment related to goods and services (including economic demands, economic withholding, and labor). The most common examples of extreme abuse were neglect, particulary physical neglect, followed by physical abuse. At the moderate and mild levels, various forms of psychological aggression were most commonly mentioned. The only significant gender difference was that men listed more instances of verbal aggression as examples of extreme abuse than women. A positive correlation was found between age and the number of abandonment examples at the extreme level. Results were interpreted from a cultural perspective.

Process Improvement Through Tool Integration in Aero-Mechanical Design

NASA Technical Reports Server (NTRS)

Briggs, Clark

2010-01-01

Emerging capabilities in commercial design tools promise to significantly improve the multi-disciplinary and inter-disciplinary design and analysis coverage for aerospace mechanical engineers. This paper explores the analysis process for two example problems of a wing and flap mechanical drive system and an aircraft landing gear door panel. The examples begin with the design solid models and include various analysis disciplines such as structural stress and aerodynamic loads. Analytical methods include CFD, multi-body dynamics with flexible bodies and structural analysis. Elements of analysis data management, data visualization and collaboration are also included.

Sierra Toolkit Manual Version 4.48.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sierra Toolkit Team

This report provides documentation for the SIERRA Toolkit (STK) modules. STK modules are intended to provide infrastructure that assists the development of computational engineering soft- ware such as finite-element analysis applications. STK includes modules for unstructured-mesh data structures, reading/writing mesh files, geometric proximity search, and various utilities. This document contains a chapter for each module, and each chapter contains overview descriptions and usage examples. Usage examples are primarily code listings which are generated from working test programs that are included in the STK code-base. A goal of this approach is to ensure that the usage examples will not fall outmore » of date. This page intentionally left blank.« less

Using Microcomputers to Teach Non-Linear Equations at Sixth Form Level.

ERIC Educational Resources Information Center

Cheung, Y. L.

1984-01-01

Promotes the use of the microcomputer in mathematics instruction, reviewing approaches to teaching nonlinear equations. Examples of computer diagrams are illustrated and compared to textbook samples. An example of a problem-solving program is included. (ML)

Q&A with Adam Warren | News | NREL

Science.gov Websites

researchers on a number of interesting projects over the years. For example, we were engaged in the Hawaii REopt. And our future investments in REopt will include stochastic models. For example, you can tell it

Amniotic Fluid Analysis

MedlinePlus

... serious consequences for the developing fetus. A few examples include tests for: TORCH : toxoplasmosis, rubella, cytomegalovirus (CMV), herpes simplex virus (HSV) Parvovirus B19 Cultures for bacterial ... may be performed in select situations, for example, if a woman is very unsure of her ...

25 CFR 1000.228 - What are examples of waivers prohibited by law?

Code of Federal Regulations, 2011 CFR

2011-04-01

... ANNUAL FUNDING AGREEMENTS UNDER THE TRIBAL SELF-GOVERNMENT ACT AMENDMENTS TO THE INDIAN SELF...? Examples of when a waiver is prohibited by Federal law include: (a) When the effect would be to waive or...

25 CFR 1000.228 - What are examples of waivers prohibited by law?

Code of Federal Regulations, 2010 CFR

2010-04-01

... ANNUAL FUNDING AGREEMENTS UNDER THE TRIBAL SELF-GOVERNMENT ACT AMENDMENTS TO THE INDIAN SELF...? Examples of when a waiver is prohibited by Federal law include: (a) When the effect would be to waive or...

Pseudoscience--Teaching by Counterexample.

ERIC Educational Resources Information Center

Hoffmaster, Steven

1986-01-01

By using pseudoscientific examples to show what science is not, instructors can generate a healthy skepticism in students while making them understand how science applies to their daily lives. A course incorporating such pseudoscientific examples (including extra-sensory perception -- ESP) is described. (JN)

Examples for Non-Ideal Solution Thermodynamics Study

ERIC Educational Resources Information Center

David, Carl W.

2004-01-01

A mathematical model of a non-ideal solution is presented, where it is shown how and where the non-ideality manifests itself in the standard thermodynamics tableau. Examples related to the non-ideal solution thermodynamics study are also included.

Interpretative Communities in Conflict: A Master Syllabus for Political Communication.

ERIC Educational Resources Information Center

Smith, Craig Allen

1992-01-01

Advocates the interpretive communities approach to teaching political communication. Discusses philosophical issues in the teaching of political communication courses, and pedagogical techniques (including concepts versus cases, clustering examples, C-SPAN video examples, and simulations and games). (SR)

The day of reckoning: Does human ultrasociality continue?

PubMed

Ristau, Carolyn A

2016-01-01

To counter human ultrasociality, alternative communities can arise (ongoing), and, unlike insects, lower echelons can unite and rebel. Examples include movements such as: "Black Lives Matter," "Fight for $15," "Occupy," and the "Village Movement." To strengthen ultrasociality, a surplus bottom echelon can be reduced: for example, by means such as imprisoning Blacks, deporting immigrants, wars, and the Holocaust. Alternatively, a new structure could be created, for example, ISIL (even more ultrasocial?).

Strong smoker interest in 'setting an example to children' by quitting: national survey data.

PubMed

Thomson, George; Wilson, Nick; Weerasekera, Deepa; Edwards, Richard

2011-02-01

To further explore smoker views on reasons to quit. As part of the multi-country ITC Project, a national sample of 1,376 New Zealand adult (18+ years) smokers was surveyed in 2007/08. This sample included boosted sampling of Māori, Pacific and Asian New Zealanders. 'Setting an example to children' was given as 'very much' a reason to quit by 51%, compared to 45% giving personal health concerns. However, the 'very much' and 'somewhat' responses (combined) were greater for personal health (81%) than 'setting an example to children' (74%). Price was the third ranked reason (67%). In a multivariate analysis, women were significantly more likely to state that 'setting an example to children' was 'very much' or 'somewhat' a reason to quit; as were Māori, or Pacific compared to European; and those suffering financial stress. The relatively high importance of 'example to children' as a reason to quit is an unusual finding, and may have arisen as a result of social marketing campaigns encouraging cessation to protect families in New Zealand. The policy implications could include a need for a greater emphasis on social reasons (e.g. 'example to children'), in pack warnings, and in social marketing for smoking cessation. © 2011 The Authors. ANZJPH © 2010 Public Health Association of Australia.

Short-Term File Reference Patterns in a UNIX Environment,

DTIC Science & Technology

1986-03-01

accounts mentioned ahose. This includes major administrative and status files (for example, /etc/ passwd ), system libraries, system include files and so on...34 files are those appearing in / and /etc. Examples are /vmunix (the bootable kernel image) and /etc/ passwd (passwords and other information on accounts...as /etc/ passwd ). The small size of opened files (55% are under 1024 bytes, a common block transfer size, and 75% are under 4096 bytes) suggests that

Separation and/or sequestration apparatus and methods

DOEpatents

Rieke, Peter C; Towne, Silas A; Coffey, Greg W; Appel, Aaron M

2015-02-03

Apparatus for separating CO.sub.2 from an electrolyte solution are provided. Example apparatus can include: a vessel defining an interior volume and configured to house an electrolyte solution; an input conduit in fluid communication with the interior volume; an output conduit in fluid communication with the interior volume; an exhaust conduit in fluid communication with the interior volume; and an anode located within the interior volume. Other example apparatus can include: an elongated vessel having two regions; an input conduit extending outwardly from the one region; an output conduit extending outwardly from the other region; an exhaust conduit in fluid communication with the one region; and an anode located within the one region. Methods for separating CO.sub.2 from an electrolyte solution are provided. Example methods can include: providing a CO.sub.2 rich electrolyte solution to a vessel containing an anode; and distributing hydrogen from the anode to acidify the electrolyte solution.

Alpha particle effects in burning tokamak plasmas: overview and specific examples

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sigmar, D.J.

1986-07-01

Using the total power balance of an ignited tokamak plasma as a guideline, a range of alpha driven effects is surveyed regarding their impact on achieving and maintaining fusion burn. Specific examples of MHD and kinetic modes and multi species transport dynamics are discussed, including the possible interaction of these categories of effects. This power balance approach rather than a straightforward enumeration of possible effects serves to reveal their non-linear dependence and the ensuing fragility of our understanding of the approach to and maintenance of ignition. Specific examples are given of the interaction between ..cap alpha..-power driven sawtoothing and idealmore » MHD stability, and direct ..cap alpha..-effects on MHD modes including kinetic corrections. Anomalous ion heat transport and central impurity peaking mechanisms and anomalous and collisional ..cap alpha..-transport including the ambipolar electric field are discussed.« less

Problems in Mathematics--Moving towards a Holistic Approach.

ERIC Educational Resources Information Center

Maree, J. G.

1992-01-01

Explanations for problems in mathematics are offered, and examples that may lead to a better understanding of problems in mathematics are discussed. Examples include the developmental, dyscalculia, dyspedagogia, behaviorist, medical, psychoanalytic, cultural, curricular, social, transactional, moral, and eclectic models. A case study exemplifies…

10 CFR 961.11 - Text of the contract.

Code of Federal Regulations, 2012 CFR

2012-01-01

... characteristic, of a specific or technical nature. It may, for example, document research, experimental... computer software documentation). Examples of technical data include research and engineering data... repository, to take title to the spent nuclear fuel or high-level radioactive waste involved as expeditiously...

10 CFR 961.11 - Text of the contract.

Code of Federal Regulations, 2011 CFR

2011-01-01

... characteristic, of a specific or technical nature. It may, for example, document research, experimental... computer software documentation). Examples of technical data include research and engineering data... repository, to take title to the spent nuclear fuel or high-level radioactive waste involved as expeditiously...

Learning Academic Content the Adventure Way.

ERIC Educational Resources Information Center

Lopez, Hector

1997-01-01

Describes and gives examples of integrating adventure activities into existing classroom curricula at three levels: review or metaphors, interwoven activities for content delivery, and total integration into classroom design. Example activities include "Speed Rabbit,""Have You Ever,""Stepping Stones,""Whale Watch," and "Mine Field." (SAS)

Interdisciplinary Social Science: An Example of Vertical and Horizontal Integrative Strategies

NASA Astrophysics Data System (ADS)

Durlabhji, Subhash

2005-03-01

A "Concept-Centered" strategy for Integrative Studies was proposed and implemented in the creation of the book Power in Focus: Perspectives from Multiple Disciplines. Essays on the ubiquitous concept of Power were solicited internationally and a final cut of ten essays from ten different disciplines, written specifically for this project, were included. This provides an example of what might be called Horizontal Integration, as it cut across multiple disciplines. One of the essays in the volume provides an example of Vertical Integration, as it applies a psychodynamic hypothesis concerning the development of Power relations among humans across hierarchical levels, from the child to the family to other groups and institutions in society, including finally entire nations and regions of the world.

C++ Programming Language

NASA Technical Reports Server (NTRS)

Shaykhian, Gholam Ali

2007-01-01

C++ Programming Language: The C++ seminar covers the fundamentals of C++ programming language. The C++ fundamentals are grouped into three parts where each part includes both concept and programming examples aimed at for hands-on practice. The first part covers the functional aspect of C++ programming language with emphasis on function parameters and efficient memory utilization. The second part covers the essential framework of C++ programming language, the object-oriented aspects. Information necessary to evaluate various features of object-oriented programming; including encapsulation, polymorphism and inheritance will be discussed. The last part of the seminar covers template and generic programming. Examples include both user defined and standard templates.

Open web system of Virtual labs for nuclear and applied physics

NASA Astrophysics Data System (ADS)

Saldikov, I. S.; Afanasyev, V. V.; Petrov, V. I.; Ternovykh, M. Yu

2017-01-01

An example of virtual lab work on unique experimental equipment is presented. The virtual lab work is software based on a model of real equipment. Virtual labs can be used for educational process in nuclear safety and analysis field. As an example it includes the virtual lab called “Experimental determination of the material parameter depending on the pitch of a uranium-water lattice”. This paper included general description of this lab. A description of a database on the support of laboratory work on unique experimental equipment which is included this work, its concept development are also presented.

System and method for leveraging human physiological traits to control microprocessor frequency

DOEpatents

Shye, Alex; Pan, Yan; Scholbrock, Benjamin; Miller, J. Scott; Memik, Gokhan; Dinda, Peter A; Dick, Robert P

2014-03-25

A system and method for leveraging physiological traits to control microprocessor frequency are disclosed. In some embodiments, the system and method may optimize, for example, a particular processor-based architecture based on, for example, end user satisfaction. In some embodiments, the system and method may determine, for example, whether their users are satisfied to provide higher efficiency, improved reliability, reduced power consumption, increased security, and a better user experience. The system and method may use, for example, biometric input devices to provide information about a user's physiological traits to a computer system. Biometric input devices may include, for example, one or more of the following: an eye tracker, a galvanic skin response sensor, and/or a force sensor.

Code Analysis and Refactoring with Clang Tools, Version 0.1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelley, Timothy M.

2016-12-23

Code Analysis and Refactoring with Clang Tools is a small set of example code that demonstrates techniques for applying tools distributed with the open source Clang compiler. Examples include analyzing where variables are used and replacing old data structures with standard structures.

Schoolyard Symbiosis.

ERIC Educational Resources Information Center

Allard, David W.

1996-01-01

Discusses different types of symbiosis--mutualism, commensalism, and parasitism--and examples of each type including lichens, legumes, mistletoe, and epiphytes. Describes how teachers can use these examples in the study of symbiosis which allows teachers to focus on many basic concepts in evolution, cell biology, ecology, and other fields of…

CIDR

Science.gov Websites

Related Links & Resources Access and Applications Access Applications Example Applications Project Research and Related (R&R) forms and the SF424 (R&R) Application Guide. Access to the CIDR Program Guidelines Example Applications All applications must include a Data Dictionary of phenotypic measures to be

21 CFR 312.32 - IND safety reports.

Code of Federal Regulations, 2010 CFR

2010-04-01

... safety reports. (a) Definitions. The following definitions of terms apply to this section:- Associated... intervention to prevent one of the outcomes listed in this definition. Examples of such medical events include... example, under this definition, hepatic necrosis would be unexpected (by virtue of greater severity) if...

What Is the Whole?

ERIC Educational Resources Information Center

Wentworth, Nancy M.; Monroe, Eula Ewing

1995-01-01

Discusses ways teachers can encourage students to construct useful meanings for the fractional unit. Provides three examples of representations of common fractions and illustrates misconceptions in fraction problems. Includes a brief summary of constructivist mathematics education and an example in which a teacher misunderstands a fractional unit.…

Boolean Networks in Inference and Dynamic Modeling of Biological Systems at the Molecular and Physiological Level

NASA Astrophysics Data System (ADS)

Thakar, Juilee; Albert, Réka

The following sections are included: * Introduction * Boolean Network Concepts and History * Extensions of the Classical Boolean Framework * Boolean Inference Methods and Examples in Biology * Dynamic Boolean Models: Examples in Plant Biology, Developmental Biology and Immunology * Conclusions * References

An Example of a Practical Biochemistry Examination for Health Professional Students.

ERIC Educational Resources Information Center

Otsuka, Allen; Kadis, Barney

1988-01-01

Uses clinical cases taken from the medical or dental literature for examination of understanding certain aspects of the dental profession. Formulates questions derived from data presented in the case or attempts to present broad principles. Includes 15 example test questions. (MVL)

Incorporating Dynamical Systems into the Traditional Curriculum.

ERIC Educational Resources Information Center

Natov, Jonathan

2001-01-01

Presents a brief overview of dynamical systems. Gives examples from dynamical systems and where they fit into the current curriculum. Points out that these examples are accessible to undergraduate freshmen and sophomore students, add continuity to the standard curriculum, and are worth including in classes. (MM)

Telemedicine: history, applications, and impact on librarianship.

PubMed Central

Zundel, K M

1996-01-01

This paper traces the uses of telecommunications in health care from the Civil War era to the present. Topics include the National Aeronautics and Space Administration's involvement in the origins of current telemedicine systems and the impact of television. Applications of telemedicine discussed include remote consultation and diagnosis, specialty clinical care (including examples from anesthesia, dermatology, cardiology, psychiatry, radiology, critical care, and oncology), and others (including examples of patient education, home monitoring, and continuing education). The concluding section highlights how telemedicine affects health sciences librarianship, beginning with the development of online computerized literature searching. This section also discusses the medical resources available to health sciences librarians as a result of the Internet. PMID:8938332

A System-of-Systems Engineering Approach for Australian Land Force Capability Integration

DTIC Science & Technology

2012-09-01

projects are those that, by their very scale and influence, shape many other projects and existing capabilities. Examples include Land 400 Land...challenges to the inherently single- project acquisition ethos predominant in both the defence and civil sectors. For example , see Henshaw (2012). This is...been applied are SoS- type glue projects , for example Land 19 Phase 7, Ground Based Air Missile Defence, and Land 400, the Land Combat Vehicle System

Dielectric Elastomer Actuated Systems and Methods

NASA Technical Reports Server (NTRS)

Dubowsky, Steven (Inventor); Hafez, Moustapha (Inventor); Lichter, Matthew (Inventor); Weiss, Peter (Inventor); Wingert, Andreas (Inventor)

2008-01-01

The system of the present invention includes an actuator having at least two electrodes, an elastomeric dielectric film disposed between the two electrodes, and a frame attached to the elastomeric dielectric film. The frame provides a linear actuation force characteristic over a displacement range. The displacement range is preferably the stroke of the actuator. The displacement range can be about 5 mm and greater. Further, the frame can include a plurality of configurations, for example, at least a rigid members coupled to a flexible member wherein the frame provides an elastic restoring force. In preferred embodiments, the rigid member can be, but is not limited to, curved beams, parallel beams, rods and plates. In a preferred embodiment the actuator can further include a passive element disposed between two flexible members such as, for example, links to tune a stiffness characteristic of the actuator. The passive element can be a bi-stable element. Further, the actuator can include a plurality of layers of the elastomeric dielectric film integrated into the frame. The elastomeric film can be made of different materials such as, for example, acrylic, silicone and latex.

Elastomeric actuator devices for magnetic resonance imaging

NASA Technical Reports Server (NTRS)

Lichter, Matthew (Inventor); Wingert, Andreas (Inventor); Hafez, Moustapha (Inventor); Dubowsky, Steven (Inventor); Jolesz, Ferenc A. (Inventor); Kacher, Daniel F. (Inventor); Weiss, Peter (Inventor)

2008-01-01

The present invention is directed to devices and systems used in magnetic imaging environments that include an actuator device having an elastomeric dielectric film with at least two electrodes, and a frame attached to the actuator device. The frame can have a plurality of configurations including, such as, for example, at least two members that can be, but not limited to, curved beams, rods, plates, or parallel beams. These rigid members can be coupled to flexible members such as, for example, links wherein the frame provides an elastic restoring force. The frame preferably provides a linear actuation force characteristic over a displacement range. The linear actuation force characteristic is defined as .+-.20% and preferably 10% over a displacement range. The actuator further includes a passive element disposed between the flexible members to tune a stiffness characteristic of the actuator. The passive element can be a bi-stable element. The preferred embodiment actuator includes one or more layers of the elastomeric film integrated into the frame. The elastomeric film can be made of many elastomeric materials such as, for example, but not limited to, acrylic, silicone and latex.

Memorable Exemplification in Undergraduate Biology: Instructor Strategies and Student Perceptions

NASA Astrophysics Data System (ADS)

Oliveira, Alandeom W.; Bretzlaff, Tiffany; Brown, Adam O.

2018-03-01

The present study examines the exemplification practices of a university biology instructor during a semester-long course. Attention is given specifically to how the instructor approaches memorable exemplification—classroom episodes identified by students as a source of memorable learning experiences. A mixed-method research approach is adopted wherein descriptive statistics is combined with qualitative multimodal analysis of video recordings and survey data. Our findings show that memorable experiencing of examples may depend on a multiplicity of factors, including whether students can relate to the example, how unique and extreme the example is, how much detail is provided, whether the example is enacted rather than told, and whether the example makes students feel sad, surprised, shocked, and/or amused. It is argued that, rather than simply assuming that all examples are equally effective, careful consideration needs be given to how exemplification can serve as an important source of memorable science learning experiences.

The Use of Monte Carlo Techniques to Teach Probability.

ERIC Educational Resources Information Center

Newell, G. J.; MacFarlane, J. D.

1985-01-01

Presents sports-oriented examples (cricket and football) in which Monte Carlo methods are used on microcomputers to teach probability concepts. Both examples include computer programs (with listings) which utilize the microcomputer's random number generator. Instructional strategies, with further challenges to help students understand the role of…

77 FR 56365 - Disclosure of Payments by Resource Extraction Issuers

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-12

.... S3816 (daily ed. May 17, 2010). Other examples of international transparency efforts include the... certain circumstances.\\41\\ For example, while opposing a general exemption for smaller reporting companies...-Doctoral Research Fellow, Columbia University School of Law (March 2, 2011) (``Maples''), Network for the...

Strategy Guideline: Quality Management in Existing Homes - Cantilever Floor Example

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taggart, J.; Sikora, J.; Wiehagen, J.

2011-12-01

This guideline is designed to highlight the QA process that can be applied to any residential building retrofit activity. The cantilevered floor retrofit detailed in this guideline is included only to provide an actual retrofit example to better illustrate the QA activities being presented.

Applications of Nano-Satellites and Cube-Satellites in Microwave and RF Domain

NASA Technical Reports Server (NTRS)

Simons, Rainee N.; Goverdhanam, Kavita

2015-01-01

This paper presents an overview of microwave technologies for Small Satellites including NanoSats and CubeSats. In addition, examples of space communication technology demonstration projects using CubeSats are presented. Furthermore, examples of miniature instruments for Earth science measurements are discussed.

Computerized Business Calculus Using Calculators, Examples from Mathematics to Finance.

ERIC Educational Resources Information Center

Vest, Floyd

1991-01-01

After discussing the role of supercalculators within the business calculus curriculum, several examples are presented which allow the reader to examine the capabilities and codes of calculators specific to different major manufacturers. The topics examined include annuities, Newton's method, fixed point iteration, graphing, solvers, and…

Applications of Nano-satellites and Cube-satellites in Microwave and RF Domain

NASA Technical Reports Server (NTRS)

Simons, Rainee N.; Goverdhanam, Kavita

2015-01-01

This paper presents an overview of microwave technologies for Small Satellites including NanoSats and CubeSats. In addition, examples of space communication technology demonstration projects using CubeSats are presented. Furthermore, examples of miniature instruments for Earth science measurements are discussed.

Probabilistic wind/tornado/missile analyses for hazard and fragility evaluations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, Y.J.; Reich, M.

Detailed analysis procedures and examples are presented for the probabilistic evaluation of hazard and fragility against high wind, tornado, and tornado-generated missiles. In the tornado hazard analysis, existing risk models are modified to incorporate various uncertainties including modeling errors. A significant feature of this paper is the detailed description of the Monte-Carlo simulation analyses of tornado-generated missiles. A simulation procedure, which includes the wind field modeling, missile injection, solution of flight equations, and missile impact analysis, is described with application examples.

Methods of making monolayers

DOEpatents

Alford, Kentin L [Pasco, WA; Simmons, Kevin L [Kennewick, WA; Samuels, William D [Richland, WA; Zemanian, Thomas S [Richland, WA; Liu, Jun [Albuquerque, NM; Shin, Yongsoon [Richland, WA; Fryxell, Glen E [Kennewick, WA

2009-12-08

The invention pertains to methods of forming monolayers on various surfaces. The surfaces can be selected from a wide array of materials, including, for example, aluminum dioxide, silicon dioxide, carbon and SiC. The substrates can be planar or porous. The monolayer is formed under enhanced pressure conditions. The monolayer contains functionalized molecules, and accordingly functionalizes a surface of the substrate. The properties of the functionalized substrate can enhance the substrate's applicability for numerous purposes including, for example, utilization in extracting contaminants, or incorporation into a polymeric matrix.

Methods of making monolayers

DOEpatents

Alford, Kentin L [Pasco, WA; Simmons, Kevin L [Kennewick, WA; Samuels, William D [Richland, WA; Zemanian, Thomas S [Richland, WA; Liu, Jun [Albuquerque, NM; Shin, Yongsoon [Richland, WA; Fryxell, Glen E [Kennewick, WA

2009-09-15

The invention pertains to methods of forming monolayers on various surfaces. The surfaces can be selected from a wide array of materials, including, for example, aluminum dioxide, silicon dioxide, carbon and SiC. The substrates can be planar or porous. The monolayer is formed under enhanced pressure conditions. The monolayer contains functionalized molecules, and accordingly functionalizes a surface of the substrate. The properties of the functionalized substrate can enhance the substrate's applicability for numerous purposes including, for example, utilization in extracting contaminants, or incorporation into a polymeric matrix.

System concepts and design examples for optical communication with planetary spacecraft

NASA Astrophysics Data System (ADS)

Lesh, James R.

Systems concepts for optical communication with future deep-space (planetary) spacecraft are described. These include not only the optical transceiver package aboard the distant spacecraft, but the earth-vicinity optical-communications receiving station as well. Both ground-based, and earth-orbiting receivers are considered. Design examples for a number of proposed or potential deep-space missions are then presented. These include an orbital mission to Saturn, a Lander and Rover mission to Mars, and an astronomical mission to a distance of 1000 astronomical units.

smwrData—An R package of example hydrologic data, version 1.1.1

USGS Publications Warehouse

Lorenz, David L.

2015-11-06

A collection of 24 datasets, including streamflow, well characteristics, groundwater elevations, and discrete water-quality concentrations, is provided to produce a consistent set of example data to demonstrate typical data manipulations or statistical analysis of hydrologic data. These example data are provided in an R package called smwrData. The data in the package have been collected by the U.S. Geological Survey or published in its reports, for example Helsel and Hirsch (2002). The R package provides a convenient mechanism for distributing the data to users of R within the U.S. Geological Survey and other users in the R community.

76 FR 52441 - Summary of Benefits and Coverage and the Uniform Glossary

Federal Register 2010, 2011, 2012, 2013, 2014

2011-08-22

... facts label that includes examples to illustrate common benefits scenarios (including pregnancy and... plan or coverage for common benefits scenarios, including pregnancy and serious or chronic medical...

Virtual Environments in Scientific Visualization

NASA Technical Reports Server (NTRS)

Bryson, Steve; Lisinski, T. A. (Technical Monitor)

1994-01-01

Virtual environment technology is a new way of approaching the interface between computers and humans. Emphasizing display and user control that conforms to the user's natural ways of perceiving and thinking about space, virtual environment technologies enhance the ability to perceive and interact with computer generated graphic information. This enhancement potentially has a major effect on the field of scientific visualization. Current examples of this technology include the Virtual Windtunnel being developed at NASA Ames Research Center. Other major institutions such as the National Center for Supercomputing Applications and SRI International are also exploring this technology. This talk will be describe several implementations of virtual environments for use in scientific visualization. Examples include the visualization of unsteady fluid flows (the virtual windtunnel), the visualization of geodesics in curved spacetime, surface manipulation, and examples developed at various laboratories.

Multifunctional and biologically active matrices from multicomponent polymeric solutions

NASA Technical Reports Server (NTRS)

Kiick, Kristi L. (Inventor); Yamaguchi, Nori (Inventor)

2010-01-01

The present invention relates to a biologically active functionalized electrospun matrix to permit immobilization and long-term delivery of biologically active agents. In particular the invention relates to a functionalized polymer matrix comprising a matrix polymer, a compatibilizing polymer and a biomolecule or other small functioning molecule. In certain aspects the electrospun polymer fibers comprise at least one biologically active molecule functionalized with low molecular weight heparin. Examples of active molecules that may be used with the multicomponent polymer of the invention include, for example, a drug, a biopolymer, for example a growth factor, a protein, a peptide, a nucleotide, a polysaccharide, a biological macromolecule or the like. The invention is further directed to the formation of functionalized crosslinked matrices, such as hydrogels, that include at least one functionalized compatibilizing polymer capable of assembly.

Water professionals and water policy in the Black Hills region

USGS Publications Warehouse

Fontaine, T.A.; Driscoll, D.G.; Erickson, J.W.; Kenner, S.J.; Sawyer, J.F.; Kendy, Eloise

1999-01-01

A case study approach based on examples from the Black Hills region is used to evaluate the role of water professionals in developing feasible and fair public policy involving water resources. Examples presented include a long-term hydrologic investigation in the Black Hills, a local wellhead protection program, issues being addressed by a local flood management commission, coordination of definitions of beneficial stream uses by two state agencies, water-quality problems related to rapid population increase in a rural area, and impacts of potential climate change on water resources. In some of these examples, the hydrologic work was separated from policy making to ensure neutrality. In other examples, involvement of the hydrologists and water resource engineers directly benefited policy development. Opportunities for increased effectiveness were observed in most of the examples.

A Pirate's Life: A Model and a Metaphor for Learning.

ERIC Educational Resources Information Center

Solomon, David L.

2002-01-01

Discusses various ways in which context may be interpreted to enhance learning and performance; illustrates domains of learning using a hockey team as an example; and suggests implications for learning, performance, and instructional design. Highlights include an ecological systems model; and examples of individual development, team learning, and…

Fortran programs for reliability analysis

Treesearch

John J. Zahn

1992-01-01

This report contains a set of FORTRAN subroutines written to calculate the Hasofer-Lind reliability index. Nonlinear failure criteria and correlated basic variables are permitted. Users may incorporate these routines into their own calling program (an example program, RELANAL, is included) and must provide a failure criterion subroutine (two example subroutines,...

75 FR 36395 - Guidance on Sound Incentive Compensation Policies

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-25

... response to comments. For example, the final guidance includes several provisions designed to reduce burden..., FDIC and OTS (collectively, the Agencies) are adopting final guidance designed to help ensure that... risks that are not consistent with the long-term health of the organization. For example, offering large...

Environmental Assessment, Change in C-17 Flight Training Operations at Grant County International Airport, Washington by Joint Base Lewis-McChord

DTIC Science & Technology

2011-10-01

ground (subsurface) deposits. Examples of prehistoric archaeological resources include village sites, campsites, lithic scatters, burials, hearths ...or hearth features), processing sites, caves and rock shelters, and petroglyph and pictograph sites. Examples of historic archaeological resources

Using Multimedia To Develop Musicianship.

ERIC Educational Resources Information Center

Fenton, Kevin

1998-01-01

Proposes that high school choir teachers utilize multimedia technology in order to provide students with simultaneous aural and visual examples of various musical concepts. Offers examples using a multimedia approach to teach John Bennet's "Weep, O Mine Eyes" and Randall Thompson's "The Road Not Taken." Includes a list for selected software. (CMK)

29 CFR Appendix A to Part 32 - Appendix A to Part 32

Code of Federal Regulations, 2010 CFR

2010-07-01

... permit a recipient to underemploy or job-stereotype that person. A restructured job, for example, could... assistant. (g) Decrease reliance solely on one form of communication. For example, for deaf participants or..., this may include making some communications available in braille, enlarged print, or on cassette...

77 FR 69593 - Atlantic Highly Migratory Species; Exempted Fishing, Scientific Research, Display, and Chartering...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-20

... platforms while conducting the specified research. As an example, NMFS has considered the recreational and... research and is therefore exempt from regulation. Examples of research conducted under LOAs include tagging... life history studies. Scientific research is not exempt from regulation under ATCA. NMFS issues SRPs...

78 FR 69823 - Atlantic Highly Migratory Species; Exempted Fishing, Scientific Research, Display, and Chartering...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-21

... the specified research. For example, in the past, NMFS has determined that commercial pelagic longline... activity meets the definition of research. Examples of research conducted under LOAs include tagging and... studies. Scientific research is not exempt from regulation under ATCA. NMFS issues SRPs which authorize...

Mixed Potentials: Experimental Illustrations of an Important Concept in Practical Electrochemistry.

ERIC Educational Resources Information Center

Power, G. P.; Ritchie, I. M.

1983-01-01

Presents a largely experimental approach to the concept of mixed potentials, pointing out the close parallel that exists between equilibrium potentials. Describes several important examples of mixed potentials, providing current-voltage and polarization curves and half reactions as examples. Includes a discussion of corrosion reactions and…

Alternative Fuels Data Center: State Requirements Boost the Transition to

Science.gov Websites

these fleets to choose between one of two compliance methods - Standard Compliance, which requires Laws and Incentives website also includes representative examples of incentives and regulations at the participating in multi-party partnerships are examples of innovative methods that will drive legislation and

Eastern Regional Technical Advisory Committee (ERTAC) Electricity Generating Unit (EGU) Emission Projection Tool (2015 EIC)

EPA Pesticide Factsheets

Class content will include examples of how the Tool maybe applied to calculate the impacts of various air pollution control regulations (for example, the Mercury and Air Toxics Rule) on future year activity as well as NOx, SO2, and CO2 emissions.

26 CFR 1.446-1 - General rule for methods of accounting.

Code of Federal Regulations, 2010 CFR

2010-04-01

... also the accounting treatment of any item. Examples of such over-all methods are the cash receipts and... special items include the accounting treatment prescribed for research and experimental expenditures, soil... books of account and on his return, as for example, a reconciliation of any differences between such...

45 CFR 612.7 - Exemptions.

Code of Federal Regulations, 2014 CFR

2014-10-01

...). Records related solely to the internal personnel rules and practices of NSF. Examples of records normally... Act of 2009, October 28, 2009, specifically cites to 5 U.S.C. 552(b)(3). Examples of records exempt... Federal Government owns or may own a right, title, or interest (including a nonexclusive license), 35 U.S...

African American Men in College

ERIC Educational Resources Information Center

Cuyjet, Michael J., Ed.

2006-01-01

This book is a much-needed resource that includes examples of real-world programs and activities to enhance academic success in the college environment for African American men. The examples are collected from a variety of institutions across the country. With contributions from leading practitioners and scholars in the field, this book explores…

78 FR 28184 - Inviting Applications for Rural Business Opportunity Grants

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-14

... long-term planning that integrates targeted investments in workforce training, infrastructure, research.... Examples of acceptable documentation include: A signed letter from the source of funds stating the amount... CFR 4284.639(d)(2)). You must describe a structural change (for example, the loss of major employer or...

Planning Curriculum Development: With Examples from Projects for the Mentally Retarded.

ERIC Educational Resources Information Center

Mayer, William V., Ed.

Presented are guidelines based on five federally funded projects for planning and developing curriculum for the mentally retarded. Discussed are the initial steps of identifying the target population, needs, and objectives. Examples of curriculum design, including the rationale and conceptual framework, are provided. Considered are elements of…

Video-Based Test Questions: A Novel Means of Evaluation

ERIC Educational Resources Information Center

Hertenstein, Matthew J.; Wayand, Joseph F.

2008-01-01

Many psychology instructors present videotaped examples of behavior at least occasionally during their courses. However, few include video clips during examinations. We provide examples of video-based questions, offer guidelines for their use, and discuss their benefits and drawbacks. In addition, we provide empirical evidence to support the use…

Chemistry. Focus on Excellence, Volume 3, Number 2.

ERIC Educational Resources Information Center

Penick, John E., Ed.; Krajcik, Joseph, Ed.

Eight examples of innovative and outstanding chemistry programs are described. These programs were selected using state criteria and at least four independent reviewers. While Project Synthesis offered a desired state, these examples of excellence provided views of what is already a reality. Included are the goals of an exemplary science program…

Testing Understanding and Understanding Testing.

ERIC Educational Resources Information Center

Pedersen, Jean; Ross, Peter

1985-01-01

Provides examples in which graphs are used in the statements of problems or in their solutions as a means of testing understanding of mathematical concepts. Examples (appropriate for a beginning course in calculus and analytic geometry) include slopes of lines and curves, quadratic formula, properties of the definite integral, and others. (JN)

A Unifying Probability Example.

ERIC Educational Resources Information Center

Maruszewski, Richard F., Jr.

2002-01-01

Presents an example from probability and statistics that ties together several topics including the mean and variance of a discrete random variable, the binomial distribution and its particular mean and variance, the sum of independent random variables, the mean and variance of the sum, and the central limit theorem. Uses Excel to illustrate these…

Saving Time with Technology

ERIC Educational Resources Information Center

Gullen, Kristine; Zimmerman, Holly

2013-01-01

In order to help teachers envision digital products in action in classrooms, the authors look at three examples of how teachers they know enhance learning time by employing technology efficiently. The examples include: (1) a social studies teacher who begins each class period with a three-question formative assessment using the website…

Studies in International Relations; A Post-Modern Example from the Twenties

ERIC Educational Resources Information Center

Petersen, Keith S.

1970-01-01

Articles published in the Quarterly are reviewed. David Y. Thomas's Mexican Legislation in the Light of Internation Law" (Sept. 1928) is reprinted as one excellent example. (In the 1920's, emphasis was on diplomatic history and international law rather than political science.) A biographical sketch is included. (SE)

Screening combinatorial arrays of inorganic materials with spectroscopy or microscopy

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2004-02-03

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial synthesis and screening of non-biological polymers

DOEpatents

Schultz, Peter G.; Xiang, Xiao-Dong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong; Wang, Kai-An

2006-04-25

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial synthesis of novel materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

1999-01-01

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial sythesis of organometallic materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2002-07-16

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Polymer arrays from the combinatorial synthesis of novel materials

DOEpatents

Schultz, Peter G.; Xiang, Xiao-Dong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong

2004-09-21

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Giant magnetoresistive cobalt oxide compounds

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

1998-01-01

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial synthesis of novel materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2002-02-12

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Giant magnetoresistive cobalt oxide compounds

DOEpatents

Schultz, P.G.; Xiang, X.; Goldwasser, I.

1998-07-07

Methods and apparatus are disclosed for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties. 58 figs.

Preparation and screening of crystalline inorganic materials

DOEpatents

Schultz, Peter G [La Jolla, CA; Xiang, Xiaodong [Danville, CA; Goldwasser, Isy [Palo Alto, CA; Brice{hacek over }o, Gabriel; Sun, Xiao-Dong [Fremont, CA; Wang, Kai-An [Cupertino, CA

2008-10-28

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Synthesis and screening combinatorial arrays of zeolites

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2003-11-18

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial synthesis of novel materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

1999-12-21

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial synthesis of novel materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2001-01-01

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Combinatorial screening of inorganic and organometallic materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy

2002-01-01

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Preparation and screening of crystalline zeolite and hydrothermally-synthesized materials

DOEpatents

Schultz, Peter G.; Xiang, Xiaodong; Goldwasser, Isy; Briceno, Gabriel; Sun, Xiao-Dong; Wang, Kai-An

2005-03-08

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Central Limit Theorem for Exponentially Quasi-local Statistics of Spin Models on Cayley Graphs

NASA Astrophysics Data System (ADS)

Reddy, Tulasi Ram; Vadlamani, Sreekar; Yogeshwaran, D.

2018-04-01

Central limit theorems for linear statistics of lattice random fields (including spin models) are usually proven under suitable mixing conditions or quasi-associativity. Many interesting examples of spin models do not satisfy mixing conditions, and on the other hand, it does not seem easy to show central limit theorem for local statistics via quasi-associativity. In this work, we prove general central limit theorems for local statistics and exponentially quasi-local statistics of spin models on discrete Cayley graphs with polynomial growth. Further, we supplement these results by proving similar central limit theorems for random fields on discrete Cayley graphs taking values in a countable space, but under the stronger assumptions of α -mixing (for local statistics) and exponential α -mixing (for exponentially quasi-local statistics). All our central limit theorems assume a suitable variance lower bound like many others in the literature. We illustrate our general central limit theorem with specific examples of lattice spin models and statistics arising in computational topology, statistical physics and random networks. Examples of clustering spin models include quasi-associated spin models with fast decaying covariances like the off-critical Ising model, level sets of Gaussian random fields with fast decaying covariances like the massive Gaussian free field and determinantal point processes with fast decaying kernels. Examples of local statistics include intrinsic volumes, face counts, component counts of random cubical complexes while exponentially quasi-local statistics include nearest neighbour distances in spin models and Betti numbers of sub-critical random cubical complexes.

Library Economic Metrics: Examples of the Comparison of Electronic and Print Journal Collections and Collection Services.

ERIC Educational Resources Information Center

King, Donald W.; Boyce, Peter B.; Montgomery, Carol Hansen; Tenopir, Carol

2003-01-01

Focuses on library economic metrics, and presents a conceptual framework for library economic metrics including service input and output, performance, usage, effectiveness, outcomes, impact, and cost and benefit comparisons. Gives examples of these measures for comparison of library electronic and print collections and collection services.…

Limitations and Functions: Four Examples of Integrating Thermodynamics

ERIC Educational Resources Information Center

Chang, Wheijen

2011-01-01

Physics students are usually unaware of the limitations and functions of related principles, and they tend to adopt "hot formulas" inappropriately. This paper introduces four real-life examples for bridging five principles, from fluids to thermodynamics, including (1) buoyant force, (2) thermal expansion, (3) the ideal-gas law, (4) the 1st law,…

Best Case Practices of Technology at Eastern New Mexico University.

ERIC Educational Resources Information Center

DeWitt, Calvin W.; Nutter, Scott; Ayala, Mary; Hall, Debra

This paper presents examples of best case practices of technology use in classes at Eastern New Mexico University (ENMU). The examples include successful and not-so-successful applications, with insights on the overall process of incorporating technology into the classroom. The paper focuses on the authors' experience in languages, business, and…

Problem-Solving Examples as Interactive Learning Objects for Educational Digital Libraries

ERIC Educational Resources Information Center

Brusilovsky, Peter; Yudelson, Michael; Hsiao, I-Han

2009-01-01

The paper analyzes three major problems encountered by our team as we endeavored to turn problem solving examples in the domain of programming into highly reusable educational activities, which could be included as first class objects in various educational digital libraries. It also suggests three specific approaches to resolving these problems,…

77 FR 74592 - Supplemental Determination for Renewable Fuels Produced Under the Final RFS2 Program From Grain...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-17

... biodiesel and renewable diesel. Regulated categories include: NAICS \\1\\ Examples of potentially regulated... and Research Institute international models as maintained by the Center for Agricultural and Rural... in the model results. For example, since FASOM is a long-term dynamic optimization model, short-term...

Differentiating Assessment in Middle and High School Mathematics and Science

ERIC Educational Resources Information Center

Waterman, Sheryn Spencer

2009-01-01

This book by Sheryn Spencer Waterman follows the bestselling "Handbook on Differentiated Instruction for Middle and High Schools." With numerous examples and strategies, it is an all-inclusive manual on assessing student readiness, interests, learning and thinking styles. It includes examples of: (1) Pre-, Formative and Summative assessments; (2)…

Differentiating Assessment in Middle and High School English and Social Studies

ERIC Educational Resources Information Center

Waterman, Sheryn Spencer

2009-01-01

This book by Sheryn Spencer Waterman follows the bestselling "Handbook on Differentiated Instruction for Middle and High Schools." With numerous examples and strategies, it is an all-inclusive manual on assessing student readiness, interests, learning and thinking styles. It includes examples of: (1) Pre-, Formative and Summative assessments; (2)…

26 CFR 1.181-1 - Deduction for qualified film and television production costs.

Code of Federal Regulations, 2014 CFR

2014-04-01

... amount of aggregate production costs that may be claimed as a deduction for a post-amendment production... provides special rules, including rules for recapture of the deduction. Section 1.181-5 provides examples... paid or incurred in connection with obtaining financing for the production (for example, premiums paid...

Oxidation resistance of silicon ceramics

NASA Technical Reports Server (NTRS)

Yasutoshi, H.; Hirota, K.

1984-01-01

Oxidation resistance, and examples of oxidation of SiC, Si3N4 and sialon are reviewed. A description is given of the oxidation mechanism, including the oxidation product, oxidation reaction and the bubble size. The oxidation reactions are represented graphically. An assessment is made of the oxidation process, and an oxidation example of silicon ceramics is given.

The Black and White Symbolic Matrix.

ERIC Educational Resources Information Center

Stabler, John R.; Goldberg, Faye J.

Although many authors have mentioned examples of how black usually connotes a negative evaluation and white a positive evaluation, the literature on the topic has not yet included an attempt to list examples comprehensively. Those which are cited here come from a wide variety of sources: primarily from dictionaries, books of slang, and personal…

The IBM PC as an Online Search Machine. Part 6: Uploading.

ERIC Educational Resources Information Center

Kolner, Stuart J.

1986-01-01

This discussion of uploading (the transmission of information from local memory to a remote system) covers benefits, disadvantages, host system features, technical aspects, and four examples of uploading using CROSSTALK. Examples include function keys, searcher assistance with commonly-used terms, the use of hedges and boiler-plate searching, and…

The role of landscape anomalies in regional plant conservation

Treesearch

S. Kelso; C. Hall; G. Maentz

2001-01-01

Landscape anomalies are regionally restricted habitats created by unusual geologic, edaphic, or hydrologic factors. Barrens, cliff faces, canyons, hanging gardens, and playas are all examples of landscape anomalies in the arid Southwest. Such sites often harbor an unusual and rich flora, including endemic, disjunct, or relictual plant species. Using examples from our...

Designing Clinical Examples To Promote Pattern Recognition: Nursing Education-Based Research and Practical Applications.

ERIC Educational Resources Information Center

Welk, Dorette Sugg

2002-01-01

Sophomore nursing students (n=162) examined scenarios depicting typical and atypical signs of heart attack. Examples were structured to include essential and nonessential symptoms, enabling pattern recognition and improved performance. The method provides a way to prepare students to anticipate and recognize life-threatening situations. (Contains…

Cyclic Polyynes as Examples of the Quantum Mechanical Particle on a Ring

ERIC Educational Resources Information Center

Anderson, Bruce D.

2012-01-01

Many quantum mechanical models are discussed as part of the undergraduate physical chemistry course to help students understand the connection between eigenvalue expressions and spectroscopy. Typical examples covered include the particle in a box, the harmonic oscillator, the rigid rotor, and the hydrogen atom. This article demonstrates that…

Discovering Reliable Sources of Biochemical Thermodynamic Data to Aid Students' Understanding

ERIC Educational Resources Information Center

Me´ndez, Eduardo; Cerda´, María F.

2016-01-01

Students of physical chemistry in biochemical disciplines need biochemical examples to capture the need, not always understood, of a difficult area in their studies. The use of thermodynamic data in the chemical reference state may lead to incorrect interpretations in the analysis of biochemical examples when the analysis does not include relevant…

Meeting the Needs of Urban Students: Creative Arts Therapy in Jersey City Public Schools

ERIC Educational Resources Information Center

Nelson, Cindy Lou

2010-01-01

This paper describes the history and development of the Jersey City Public Schools creative arts therapy program. Creative arts therapists contributed examples of their work throughout the district that provide a window into their respective school settings. Examples include technology-based art therapy, an extended school year program,…

Czech Basic Course: Verb List.

ERIC Educational Resources Information Center

Stoner, William; Vit, Karel V.

This compilation of verbs, intended for students of the Defense Language Institute (DLI) Basic Course, provides brief definitions for each entry. No sentence examples are included. The text is intended to serve as a compact reference and study aid. Examples are selected from the Basic Course and the DLI Czech-English Dictionary. Entries are listed…

Using Physics Principles in the Teaching of Chemistry.

ERIC Educational Resources Information Center

Gulden, Warren

1996-01-01

Presents three examples that show how students can use traditional physics principles or laws for the purpose of understanding chemistry better. Examples include Coulomb's Law and melting points, the Faraday Constant, and the Rydberg Constant. Presents a list of some other traditional topics in a chemistry course that could be enhanced by the…

Grid Integrated Distributed PV (GridPV) Version 2.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reno, Matthew J.; Coogan, Kyle

2014-12-01

This manual provides the documentation of the MATLAB toolbox of functions for using OpenDSS to simulate the impact of solar energy on the distribution system. The majority of the functio ns are useful for interfacing OpenDSS and MATLAB, and they are of generic use for commanding OpenDSS from MATLAB and retrieving information from simulations. A set of functions is also included for modeling PV plant output and setting up the PV plant in th e OpenDSS simulation. The toolbox contains functions for modeling the OpenDSS distribution feeder on satellite images with GPS coordinates. Finally, example simulations functions are included tomore » show potential uses of the toolbox functions. Each function i n the toolbox is documented with the function use syntax, full description, function input list, function output list, example use, and example output.« less

Gene-gene-environment interactions between drugs, transporters, receptors, and metabolizing enzymes: Statins, SLCO1B1, and CYP3A4 as an example.

PubMed

Sadee, Wolfgang

2013-09-01

Pharmacogenetic biomarker tests include mostly specific single gene-drug pairs, capable of accounting for a portion of interindividual variability in drug response and toxicity. However, multiple genes are likely to contribute, either acting independently or epistatically, with the CYP2C9-VKORC1-warfarin test panel, an example of a clinically used gene-gene-dug interaction. I discuss here further instances of gene-gene-drug interactions, including a proposed dynamic effect on statin therapy by genetic variants in both a transporter (SLCO1B1) and a metabolizing enzyme (CYP3A4) in liver cells, the main target site where statins block cholesterol synthesis. These examples set a conceptual framework for developing diagnostic panels involving multiple gene-drug combinations. Copyright © 2013 Wiley Periodicals, Inc.

Innovation in Flight: Research of the NASA Langley Research Center on Revolutionary Advanced Concepts for Aeronautics

NASA Technical Reports Server (NTRS)

Chambers, Joseph R.

2005-01-01

The goal of this publication is to provide an overview of the topic of revolutionary research in aeronautics at Langley, including many examples of research efforts that offer significant potential benefits, but have not yet been applied. The discussion also includes an overview of how innovation and creativity is stimulated within the Center, and a perspective on the future of innovation. The documentation of this topic, especially the scope and experiences of the example research activities covered, is intended to provide background information for future researchers.

The Primates.

ERIC Educational Resources Information Center

Naturescope, 1986

1986-01-01

Presents information about primates, including definitions and examples. Includes the activities "Thumbless Relay" and "Face It," which relate attributes of primates. Includes a story about chimpanzees along with discussion questions about the story. Reproducible worksheets and a quiz are also provided. (TW)

Nanomechanical testing system

DOEpatents

Vodnick, David James; Dwivedi, Arpit; Keranen, Lucas Paul; Okerlund, Michael David; Schmitz, Roger William; Warren, Oden Lee; Young, Christopher David

2014-07-08

An automated testing system includes systems and methods to facilitate inline production testing of samples at a micro (multiple microns) or less scale with a mechanical testing instrument. In an example, the system includes a probe changing assembly for coupling and decoupling a probe of the instrument. The probe changing assembly includes a probe change unit configured to grasp one of a plurality of probes in a probe magazine and couple one of the probes with an instrument probe receptacle. An actuator is coupled with the probe change unit, and the actuator is configured to move and align the probe change unit with the probe magazine and the instrument probe receptacle. In another example, the automated testing system includes a multiple degree of freedom stage for aligning a sample testing location with the instrument. The stage includes a sample stage and a stage actuator assembly including translational and rotational actuators.

Nanomechanical testing system

DOEpatents

Vodnick, David James; Dwivedi, Arpit; Keranen, Lucas Paul; Okerlund, Michael David; Schmitz, Roger William; Warren, Oden Lee; Young, Christopher David

2015-01-27

An automated testing system includes systems and methods to facilitate inline production testing of samples at a micro (multiple microns) or less scale with a mechanical testing instrument. In an example, the system includes a probe changing assembly for coupling and decoupling a probe of the instrument. The probe changing assembly includes a probe change unit configured to grasp one of a plurality of probes in a probe magazine and couple one of the probes with an instrument probe receptacle. An actuator is coupled with the probe change unit, and the actuator is configured to move and align the probe change unit with the probe magazine and the instrument probe receptacle. In another example, the automated testing system includes a multiple degree of freedom stage for aligning a sample testing location with the instrument. The stage includes a sample stage and a stage actuator assembly including translational and rotational actuators.

Nanomechanical testing system

DOEpatents

Vodnick, David James; Dwivedi, Arpit; Keranen, Lucas Paul; Okerlund, Michael David; Schmitz, Roger William; Warren, Oden Lee; Young, Christopher David

2015-02-24

An automated testing system includes systems and methods to facilitate inline production testing of samples at a micro (multiple microns) or less scale with a mechanical testing instrument. In an example, the system includes a probe changing assembly for coupling and decoupling a probe of the instrument. The probe changing assembly includes a probe change unit configured to grasp one of a plurality of probes in a probe magazine and couple one of the probes with an instrument probe receptacle. An actuator is coupled with the probe change unit, and the actuator is configured to move and align the probe change unit with the probe magazine and the instrument probe receptacle. In another example, the automated testing system includes a multiple degree of freedom stage for aligning a sample testing location with the instrument. The stage includes a sample stage and a stage actuator assembly including translational and rotational actuators.

Biomolecular engineering of intracellular switches in eukaryotes

PubMed Central

Pastuszka, M.K.; Mackay, J.A.

2010-01-01

Tools to selectively and reversibly control gene expression are useful to study and model cellular functions. When optimized, these cellular switches can turn a protein's function “on” and “off” based on cues designated by the researcher. These cues include small molecules, drugs, hormones, and even temperature variations. Here we review three distinct areas in gene expression that are commonly targeted when designing cellular switches. Transcriptional switches target gene expression at the level of mRNA polymerization, with examples including the tetracycline gene induction system as well as nuclear receptors. Translational switches target the process of turning the mRNA signal into protein, with examples including riboswitches and RNA interference. Post-translational switches control how proteins interact with one another to attenuate or relay signals. Examples of post-translational modification include dimerization and intein splicing. In general, the delay times between switch and effect decreases from transcription to translation to post-translation; furthermore, the fastest switches may offer the most elegant opportunities to influence and study cell behavior. We discuss the pros and cons of these strategies, which directly influence their usefulness to study and implement drug targeting at the tissue and cellular level. PMID:21209849

Tackling the Sixth State

ERIC Educational Resources Information Center

Kolm, Henry H.

1975-01-01

Describes the process of high gradient magnetic separation which gives promise as a method of large scale removal of colloidal impurities including bacteria and viruses. Examples and diagrams are included. (GH)

Should industry care for children? Public health advocacy and law in Australia.

PubMed

Stanley, F; Daube, M

2009-03-01

This paper uses examples to illustrate the challenges to health and law professionals interested in public health interventions to reduce the negative impact of companies making money by selling products that put children and young people at risk. Examples included are folate to prevent neural tube defects, with issues around the food industry attempting to block mandatory fortification of flour with folate; fetal alcohol syndrome and hazardous drinking in young people, with a focus on the actions of the alcohol industry including vendors; smoking and the ways in which the tobacco industry still target children; and childhood obesity, with problems again from the food and drink industries including vendors.

Medicines for back pain

MedlinePlus

... direct care, they can be effective in reducing pain. Examples of narcotics include: Codeine Fentanyl -- available as a patch Hydrocodone Hydromorphone Morphine Oxycodone Tramadol Possible side effects of these drugs include: Drowsiness ...

Medical Information Management System (MIMS): A generalized interactive information system

NASA Technical Reports Server (NTRS)

Alterescu, S.; Friedman, C. A.; Hipkins, K. R.

1975-01-01

An interactive information system is described. It is a general purpose, free format system which offers immediate assistance where manipulation of large data bases is required. The medical area is a prime area of application. Examples of the system's operation, commentary on the examples, and a complete listing of the system program are included.

78 FR 58202 - Federal Tort Claims Act (FTCA) Medical Malpractice Program Regulations: Clarification of FTCA...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-23

... added examples of services covered under the FTCA involving individual emergency care provided to a non-health center patient and updated the September 1995 Notice immunization example to include events to...) on May 8, 1995, and added a new part 6 to 42 CFR Chapter I, Subchapter A. This rule describes the...

26 CFR 1.1244(d)-2 - Increases in basis of section 1244 stock.

Code of Federal Regulations, 2010 CFR

2010-04-01

... issuance there is for any reason, including the operation of section 1376(a), an increase in the basis of.... Therefore, a loss on stock, the basis of which has been increased subsequent to its issuance, must be... be illustrated by the following example: Example: For $10,000 a corporation issues 100 shares of...

Importance of fish behaviour in modelling conservation problems: food limitation as an example

Treesearch

Steven Railsback; Bret Harvey

2011-01-01

Simulation experiments using the inSTREAM individual-based brown trout Salmo trutta population model explored the role of individual adaptive behaviour in food limitation, as an example of how behaviour can affect managers’ understanding of conservation problems. The model includes many natural complexities in habitat (spatial and temporal variation in characteristics...

2 CFR 180.25 - What must a Federal agency address in its implementation of the guidance?

Code of Federal Regulations, 2010 CFR

2010-01-01

...: (1) Identify any specific types of transactions that the Federal agency includes as “nonprocurement transactions” in addition to the examples provided in § 180.970. (2) Identify any types of nonprocurement....215(g)(2). (3) Identify specific examples of types of individuals who would be “principals” under the...

The Perceived Usefulness of a Summary of Performance by Postsecondary Disability Service Providers

ERIC Educational Resources Information Center

de Vries, Rebecca S.

2011-01-01

This study investigated postsecondary disability service providers' (DSP) perceived usefulness of an example of a well-developed SOP. This example SOP was included in a 22 question survey, administered electronically to DSPs who are members of the Association on Higher Education and Disability (AHEAD). The participants (n=298) were asked to rate…

Degradative Enzymes from the Pharmacy or Health Food Store: Interesting Examples for Introductory Biology Laboratories

ERIC Educational Resources Information Center

Deutch, Charles E.

2007-01-01

Degradative enzymes in over-the-counter products from pharmacies and health food stores provide good examples of biological catalysis. These include [beta]-galactosidase in Lactaid[TM], [alpha]-galactosidase in Beano[R], [alpha]-amylase and proteases in digestive aids, and proteases in contact lens cleaners. These enzymes can be studied…

Medical Information Management System (MIMS): An automated hospital information system

NASA Technical Reports Server (NTRS)

Alterescu, S.; Simmons, P. B.; Schwartz, R. A.

1971-01-01

An automated hospital information system that handles all data related to patient-care activities is described. The description is designed to serve as a manual for potential users, nontechnical medical personnel who may use the system. Examples of the system's operation, commentary on the examples, and a complete listing of the system program are included.

Violence in the Schools: Programs and Policies for Prevention. A Report from the Canadian Education Association.

ERIC Educational Resources Information Center

MacDougall, Jyl

This publication offers some insight into the problem of violence in Canadian schools and provides examples of ways to reduce it. The forms of violent activities examined include youth/youth-gang violence, violence against teachers, bullying, sexual harassment, and sexual assault. Each chapter presents research findings and examples of programs…

Suppressor Effects in Coping Research with African American Adolescents from Low-Income Communities

ERIC Educational Resources Information Center

Gaylord-Harden, Noni K.; Cunningham, Jamila A.; Holmbeck, Grayson N.; Grant, Kathryn E.

2010-01-01

Objective: The purpose of the current study was to demonstrate the replicable nature of statistical suppressor effects in coping research through 2 examples with African American adolescents from low-income communities. Method: Participants in the 1st example included 497 African American adolescents (mean age = 12.61 years, SD = 0.99; 57% female)…

78 FR 19713 - Possible Role of Independent Third Parties in Industry-Sponsored Tobacco Product Research...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-02

... tobacco product research could be subject to third-party governance? For example, could it be applied to... governance? For example, should both the design and conduct of research studies be subject to third-party... more key functions, including the design and conduct of research, the oversight of specific studies...

Guide on Data Models in the Selection and Use of Database Management Systems. Final Report.

ERIC Educational Resources Information Center

Gallagher, Leonard J.; Draper, Jesse M.

A tutorial introduction to data models in general is provided, with particular emphasis on the relational and network models defined by the two proposed ANSI (American National Standards Institute) database language standards. Examples based on the network and relational models include specific syntax and semantics, while examples from the other…

26 CFR 1.963-0 - Repeal of section 963; effective dates.

Code of Federal Regulations, 2012 CFR

2012-04-01

... after December 31, 1975, then a foreign corporation shall be includible in such election only if— (i) It... (i) of this paragraph from a chain or group election of a United States shareholder for its taxable.... The application of this paragraph may be illustrated by the following example: Example. (a) M is a...

Dressing Down

NASA Technical Reports Server (NTRS)

Schabes, Harvey

2003-01-01

Smiles and laughter reduce stress. They also renew energy and trust in ourselves and others. A characteristic of any good project manager is his or her willingness to challenge the conventional way of doing things. Use whatever tools you have available, including a sense of humor. Do you have examples of how you learned from experience, especially examples that challenged the status quo?

29 CFR 2520.104-20 - Limited exemption for certain small welfare plans.

Code of Federal Regulations, 2012 CFR

2012-07-01

... from employee benefit plans for research and analysis (section 513). (d) Examples. (1) A welfare plan... administrator of an employee benefit plan from any other requirement of title I of the Act, including the... and maintained in the same way as the plan described in example (1), except that a trade association...

29 CFR 2520.104-20 - Limited exemption for certain small welfare plans.

Code of Federal Regulations, 2010 CFR

2010-07-01

... from employee benefit plans for research and analysis (section 513). (d) Examples. (1) A welfare plan... administrator of an employee benefit plan from any other requirement of title I of the Act, including the... and maintained in the same way as the plan described in example (1), except that a trade association...

Application of Interactive Multimedia Tools in Teaching Mathematics--Examples of Lessons from Geometry

ERIC Educational Resources Information Center

Milovanovic, Marina; Obradovic, Jasmina; Milajic, Aleksandar

2013-01-01

This article presents the benefits and importance of using multimedia in the math classes by the selected examples of multimedia lessons from geometry (isometric transformations and regular polyhedra). The research included two groups of 50 first year students of the Faculty of the Architecture and the Faculty of Civil Construction Management.…

www.teld.net: Online Courseware Engine for Teaching by Examples and Learning by Doing.

ERIC Educational Resources Information Center

Huang, G. Q.; Shen, B.; Mak, K. L.

2001-01-01

Describes TELD (Teaching by Examples and Learning by Doing), a Web-based online courseware engine for higher education. Topics include problem-based learning; project-based learning; case methods; TELD as a Web server; course materials; TELD as a search engine; and TELD as an online virtual classroom for electronic delivery of electronic…

Petroleum accounting principles, procedures, and issues

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brock, H.R.; Klingstedt, J.P.; Jones, D.M.

1985-01-01

This book begins with the basics and leads one through the complexities of accounting and reporting for the industry. It presents the material one needs as an accountant in the petroleum industry. Examples deal with real problems and issues. It also includes numerous illustrations and examples, as well as sample forms, lease agreements, and industry and governmental regulations.

Helping secondary school students develop a conceptual understanding of refraction

NASA Astrophysics Data System (ADS)

Ashmann, Scott; Anderson, Charles W.; Boeckman, Heather

2016-07-01

Using real-world examples, ray diagrams, and a cognitive apprenticeship cycle, this paper focuses on developing students’ conceptual (not mathematical) understanding of refraction. Refraction can be a difficult concept for students to comprehend if they do not have well-designed opportunities to practice explaining situations where reflection and refraction occur. The use of ray diagrams can be useful in (a) the teacher modelling a correct explanation to a situation where refraction occurs and (b) for students to create as they practice other examples. This paper includes eight examples of increasing complexity that use a cognitive apprenticeship cycle approach to scaffold student learning. The first examples (rock fish, floating penny) are shown and a solution is modeled using a ray diagram. Three more examples (bent pencil, dropping an item in water, sunrise/sunset) are presented for students to practice, with each becoming more sophisticated. Three assessment exercises are then provided (two dots, three coins, broken tube).

A Note on Multigrid Theory for Non-nested Grids and/or Quadrature

NASA Technical Reports Server (NTRS)

Douglas, C. C.; Douglas, J., Jr.; Fyfe, D. E.

1996-01-01

We provide a unified theory for multilevel and multigrid methods when the usual assumptions are not present. For example, we do not assume that the solution spaces or the grids are nested. Further, we do not assume that there is an algebraic relationship between the linear algebra problems on different levels. What we provide is a computationally useful theory for adaptively changing levels. Theory is provided for multilevel correction schemes, nested iteration schemes, and one way (i.e., coarse to fine grid with no correction iterations) schemes. We include examples showing the applicability of this theory: finite element examples using quadrature in the matrix assembly and finite volume examples with non-nested grids. Our theory applies directly to other discretizations as well.

Tutorial in medical decision modeling incorporating waiting lines and queues using discrete event simulation.

PubMed

Jahn, Beate; Theurl, Engelbert; Siebert, Uwe; Pfeiffer, Karl-Peter

2010-01-01

In most decision-analytic models in health care, it is assumed that there is treatment without delay and availability of all required resources. Therefore, waiting times caused by limited resources and their impact on treatment effects and costs often remain unconsidered. Queuing theory enables mathematical analysis and the derivation of several performance measures of queuing systems. Nevertheless, an analytical approach with closed formulas is not always possible. Therefore, simulation techniques are used to evaluate systems that include queuing or waiting, for example, discrete event simulation. To include queuing in decision-analytic models requires a basic knowledge of queuing theory and of the underlying interrelationships. This tutorial introduces queuing theory. Analysts and decision-makers get an understanding of queue characteristics, modeling features, and its strength. Conceptual issues are covered, but the emphasis is on practical issues like modeling the arrival of patients. The treatment of coronary artery disease with percutaneous coronary intervention including stent placement serves as an illustrative queuing example. Discrete event simulation is applied to explicitly model resource capacities, to incorporate waiting lines and queues in the decision-analytic modeling example.

Combinatorial synthesis of inorganic or composite materials

DOEpatents

Goldwasser, Isy; Ross, Debra A.; Schultz, Peter G.; Xiang, Xiao-Dong; Briceno, Gabriel; Sun, Xian-Dong; Wang, Kai-An

2010-08-03

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials or, alternatively, allowing the components to interact to form at least two different materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, nonbiological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Misinformation in eating disorder communications: Implications for science communication policy

NASA Astrophysics Data System (ADS)

Radford, Benjamin

Though eating disorders are a serious public health threat, misinformation about these potentially deadly diseases is widespread. This study examines eating disorder information from a wide variety of sources including medical journals, news reports, and popular social activist authors. Examples of misinformation were identified, and three aspects of eating disorders (prevalence, mortality, and etiology) were chosen as key indicators of scientific illiteracy about those illnesses. A case study approach was then adopted to trace examples of misinformation to their original sources whenever possible. A dozen examples include best-selling books, national eating disorder information clearinghouses; the news media; documentary feature films; and a PBS television Nova documentary program. The results provide an overview of the ways in which valid information becomes flawed, including poor journalism, lack of fact-checking, plagiarism, and typographical errors. Less obvious---and perhaps even more important---much of the misinformation results from scientific research being co-opted to promote specific sociopolitical agendas. These results highlight a significant gap in science communication between researchers, the medical community, and the public regarding these diseases, and recommendations to address the problem are offered.

Why don't dentists talk to patients about oral cancer?

PubMed

Awojobi, O; Newton, J T; Scott, S E

2015-05-08

Up to half of oral cancer patients are diagnosed with advanced lesions. One route to early diagnosis could involve dentists raising awareness of oral cancer through discussions with patients, emphasising prompt help-seeking. This study explores opinions and practices of dentists regarding discussing oral cancer with patients including views on barriers and facilitators. Qualitative in-depth interviews.Setting Dentists working in general dental practices in the United Kingdom were interviewed in 2013. In-depth interviews with dentists (n = 16) were conducted. Interviews were audio-recorded and transcribed. Data was analysed using framework analysis. Dentists recognised the importance of raising awareness but identified several barriers to discussions including system factors (for example, time constraints and a lack of financial incentive), patient factors (for example, fear of invoking undue anxiety) and dentist factors (for example, a lack of sufficient knowledge, training and self-confidence). Facilitators included developing practice standards and good dentist-patient relationships. Identified barriers may hold back efforts to raise awareness of oral cancer and could be targeted in future initiatives to encourage early detection.

ADS: A FORTRAN program for automated design synthesis: Version 1.10

NASA Technical Reports Server (NTRS)

Vanderplaats, G. N.

1985-01-01

A new general-purpose optimization program for engineering design is described. ADS (Automated Design Synthesis - Version 1.10) is a FORTRAN program for solution of nonlinear constrained optimization problems. The program is segmented into three levels: strategy, optimizer, and one-dimensional search. At each level, several options are available so that a total of over 100 possible combinations can be created. Examples of available strategies are sequential unconstrained minimization, the Augmented Lagrange Multiplier method, and Sequential Linear Programming. Available optimizers include variable metric methods and the Method of Feasible Directions as examples, and one-dimensional search options include polynomial interpolation and the Golden Section method as examples. Emphasis is placed on ease of use of the program. All information is transferred via a single parameter list. Default values are provided for all internal program parameters such as convergence criteria, and the user is given a simple means to over-ride these, if desired.

Human-computer interface incorporating personal and application domains

DOEpatents

Anderson, Thomas G [Albuquerque, NM

2011-03-29

The present invention provides a human-computer interface. The interface includes provision of an application domain, for example corresponding to a three-dimensional application. The user is allowed to navigate and interact with the application domain. The interface also includes a personal domain, offering the user controls and interaction distinct from the application domain. The separation into two domains allows the most suitable interface methods in each: for example, three-dimensional navigation in the application domain, and two- or three-dimensional controls in the personal domain. Transitions between the application domain and the personal domain are under control of the user, and the transition method is substantially independent of the navigation in the application domain. For example, the user can fly through a three-dimensional application domain, and always move to the personal domain by moving a cursor near one extreme of the display.

Human-computer interface incorporating personal and application domains

DOEpatents

Anderson, Thomas G.

2004-04-20

The present invention provides a human-computer interface. The interface includes provision of an application domain, for example corresponding to a three-dimensional application. The user is allowed to navigate and interact with the application domain. The interface also includes a personal domain, offering the user controls and interaction distinct from the application domain. The separation into two domains allows the most suitable interface methods in each: for example, three-dimensional navigation in the application domain, and two- or three-dimensional controls in the personal domain. Transitions between the application domain and the personal domain are under control of the user, and the transition method is substantially independent of the navigation in the application domain. For example, the user can fly through a three-dimensional application domain, and always move to the personal domain by moving a cursor near one extreme of the display.

10 CFR 961.11 - Text of the contract.

Code of Federal Regulations, 2014 CFR

2014-01-01

... program including information on cost projections, project plans and progress reports. 5. (a) Beginning on...-type documents or computer software (including computer programs, computer software data bases, and computer software documentation). Examples of technical data include research and engineering data...

10 CFR 961.11 - Text of the contract.

Code of Federal Regulations, 2013 CFR

2013-01-01

... program including information on cost projections, project plans and progress reports. 5. (a) Beginning on...-type documents or computer software (including computer programs, computer software data bases, and computer software documentation). Examples of technical data include research and engineering data...

Chemical Mixture Risk Assessment Additivity-Based Approaches

EPA Science Inventory

Powerpoint presentation includes additivity-based chemical mixture risk assessment methods. Basic concepts, theory and example calculations are included. Several slides discuss the use of "common adverse outcomes" in analyzing phthalate mixtures.

We Must Take the Next Steps Towards Safe, Routine Space Travel

NASA Technical Reports Server (NTRS)

Lyles, G. M.

2000-01-01

This paper presents, in viewgraph form, six in a half generations of airplanes in a century. Some of the topics include: 1) Enterprise goals; 2) Generations of Reusable Launch Vehicles; 3) Space Transportation Across NASA; 4) Three Tiered Implementation Approach for Future Space Transportation Technology; 5) Develop a Comprehensive, Agency Level Space Transportation Plan That Will Enable NASA's Strategic Plan; 6) Timeline for Addressing NASA's Needs; 7) Significant 2nd Generation Technology Drivers; 8) Example Large Scale Ground Demonstrations; and 9) Example Pathfinder Demonstrations. The paper also includes various aircraft designs and propulsion system technology.

Range estimates of whale signals recorded by triplets of hydrophones.

NASA Astrophysics Data System (ADS)

Le Bras, R. J.; Nielsen, P.

2017-12-01

The International Monitoring System of the Comprehensive Nuclear-Test-Ban Treaty Organization includes a hydroacoustic network as one of the monitoring technologies. The underwater part of this network includes six stations and is now complete with the recent installation of the HA04 station located in the Southern Ocean island of Crozet (France). A large number of calls emanating from marine mammals are recorded by the hydrophones, and we present examples where the animals are sufficiently close that a range estimate can be attempted. We also present examples of scattered arrivals and related interpretations.

Thermo-elastoviscoplastic snapthrough behavior of cylindrical panels

NASA Technical Reports Server (NTRS)

Song, Y.; Simitses, G. J.

1992-01-01

The thermo-elastoviscoplastic snapthrough behavior of simply supported cylindrical panels is investigated. The analysis is based on nonlinear kinematic relations and nonlinear rate-dependent unified constitutive equations which include both Bodner-Partom's and Walker's material models. A finite element approach is employed to predict the inelastic buckling behavior. Numerical examples are given to demonstrate the effects of several parameters which include the temperature, thickness and flatness of the panel. Comparisons of buckling responses between Bodner-Partom's model and Walker's model are given. The creep buckling behavior, as an example of time-dependent inelastic deformation, is also presented.

Determination of stresses in gas-turbine disks subjected to plastic flow and creep

NASA Technical Reports Server (NTRS)

Millenson, M B; Manson, S S

1948-01-01

A finite-difference method previously presented for computing elastic stresses in rotating disks is extended to include the computation of the disk stresses when plastic flow and creep are considered. A finite-difference method is employed to eliminate numerical integration and to permit nontechnical personnel to make the calculations with a minimum of engineering supervision. Illustrative examples are included to facilitate explanation of the procedure by carrying out the computations on a typical gas-turbine disk through a complete running cycle. The results of the numerical examples presented indicate that plastic flow markedly alters the elastic-stress distribution.

Users manual for the Variable dimension Automatic Synthesis Program (VASP)

NASA Technical Reports Server (NTRS)

White, J. S.; Lee, H. Q.

1971-01-01

A dictionary and some problems for the Variable Automatic Synthesis Program VASP are submitted. The dictionary contains a description of each subroutine and instructions on its use. The example problems give the user a better perspective on the use of VASP for solving problems in modern control theory. These example problems include dynamic response, optimal control gain, solution of the sampled data matrix Ricatti equation, matrix decomposition, and pseudo inverse of a matrix. Listings of all subroutines are also included. The VASP program has been adapted to run in the conversational mode on the Ames 360/67 computer.

Applications in Robotics and Controls

NASA Astrophysics Data System (ADS)

Youcef-Toumi, Kamal

2008-06-01

Recent industry trends have set new standards in business dealings and trades. Issues such as time to market, shoter market wondows, product performance, rapid increase of product complexity, costly mistakes, costly late introductions, and customer expectations have changed significantly. These trends have also influenced to a great extend the academic world. Some of these trends will be illustrated through examples which include automated systems, robotics, biotechnollogy, and nanotechnology. The examples will include concepts and prototypes of engineering systems in the macro, micro and nanodomains. The presentation also amphasizes the merging of the traditionally segregated disciplines into one multidisciplinary modeling, design, optimization and control approach.

Bacterial community changes in copper and PEX drinking water pipeline biofilms under extra disinfection and magnetic water treatment.

PubMed

Inkinen, J; Jayaprakash, B; Ahonen, M; Pitkänen, T; Mäkinen, R; Pursiainen, A; Santo Domingo, J W; Salonen, H; Elk, M; Keinänen-Toivola, M M

2018-02-01

To study the stability of biofilms and water quality in pilot scale drinking water copper and PEX pipes in changing conditions (extra disinfection, magnetic water treatment, MWT). Next-generation sequencing (NGS) of 16S ribosomal RNA genes (rDNA) to describe total bacterial community and ribosomal RNA (rRNA) to describe active bacterial members in addition to traditional microbiological methods were applied. Biofilms from control copper and PEX pipes shared same most abundant bacteria (Methylobacterium spp., Sphingomonas spp., Zymomonas spp.) and average species diversities (Shannon 3·8-4·2) in rDNA and rRNA libraries, whereas few of the taxa differed by their abundance such as lower total Mycobacterium spp. occurrence in copper (<0·02%) to PEX (<0·2%) pipes. Extra disinfection (total chlorine increase from c. 0·5 to 1 mg l -1 ) affected total and active population in biofilms seen as decrease in many bacterial species and diversity (Shannon 2·7, P < 0·01, rRNA) and increase in Sphingomonas spp. as compared to control samples. Furthermore, extra-disinfected copper and PEX samples formed separate clusters in unweighted non-metric multidimensional scaling plot (rRNA) similarly to MWT-treated biofilms of copper (but not PEX) pipes that instead showed higher species diversity (Shannon 4·8, P < 0·05 interaction). Minor chlorine dose addition increased selection pressure and many species were sensitive to chlorination. Pipe material seemed to affect mycobacteria occurrence, and bacterial communities with MWT in copper but not in PEX pipes. This study using rRNA showed that chlorination affects especially active fraction of bacterial communities. Copper and PEX differed by the occurrence of some bacterial members despite similar community profiles. © 2017 The Society for Applied Microbiology.

Controlling microbial contamination during hydrolysis of AFEX-pretreated corn stover and switchgrass: Effects on hydrolysate composition, microbial response and fermentation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Serate, Jose; Xie, Dan; Pohlmann, Edward

Microbial conversion of lignocellulosic feedstocks into biofuels remains an attractive means to produce sustainable energy. It is essential to produce lignocellulosic hydrolysates in a consistent manner in order to study microbial performance in different feedstock hydrolysates. Because of the potential to introduce microbial contamination from the untreated biomass or at various points during the process, it can be difficult to control sterility during hydrolysate production. In this study, we compared hydrolysates produced from AFEX-pretreated corn stover and switchgrass using two different methods to control contamination: either by autoclaving the pretreated feedstocks prior to enzymatic hydrolysis, or by introducing antibiotics duringmore » the hydrolysis of non-autoclaved feedstocks. We then performed extensive chemical analysis, chemical genomics, and comparative fermentations to evaluate any differences between these two different methods used for producing corn stover and switchgrass hydrolysates. Autoclaving the pretreated feedstocks could eliminate the contamination for a variety of feedstocks, whereas the antibiotic gentamicin was unable to control contamination consistently during hydrolysis. Compared to the addition of gentamicin, autoclaving of biomass before hydrolysis had a minimal effect on mineral concentrations, and showed no significant effect on the two major sugars (glucose and xylose) found in these hydrolysates. However, autoclaving elevated the concentration of some furanic and phenolic compounds. Chemical genomics analyses using Saccharomyces cerevisiae strains indicated a high correlation between the AFEX-pretreated hydrolysates produced using these two methods within the same feedstock, indicating minimal differences between the autoclaving and antibiotic methods. Comparative fermentations with S. cerevisiae and Zymomonas mobilis also showed that autoclaving the AFEX-pretreated feedstocks had no significant effects on microbial performance in these hydrolysates. In conclusion, our results showed that autoclaving the pretreated feedstocks offered advantages over the addition of antibiotics for hydrolysate production. The autoclaving method produced a more consistent quality of hydrolysate.« less

Controlling microbial contamination during hydrolysis of AFEX-pretreated corn stover and switchgrass: Effects on hydrolysate composition, microbial response and fermentation

DOE PAGES

Serate, Jose; Xie, Dan; Pohlmann, Edward; ...

2015-11-14

Microbial conversion of lignocellulosic feedstocks into biofuels remains an attractive means to produce sustainable energy. It is essential to produce lignocellulosic hydrolysates in a consistent manner in order to study microbial performance in different feedstock hydrolysates. Because of the potential to introduce microbial contamination from the untreated biomass or at various points during the process, it can be difficult to control sterility during hydrolysate production. In this study, we compared hydrolysates produced from AFEX-pretreated corn stover and switchgrass using two different methods to control contamination: either by autoclaving the pretreated feedstocks prior to enzymatic hydrolysis, or by introducing antibiotics duringmore » the hydrolysis of non-autoclaved feedstocks. We then performed extensive chemical analysis, chemical genomics, and comparative fermentations to evaluate any differences between these two different methods used for producing corn stover and switchgrass hydrolysates. Autoclaving the pretreated feedstocks could eliminate the contamination for a variety of feedstocks, whereas the antibiotic gentamicin was unable to control contamination consistently during hydrolysis. Compared to the addition of gentamicin, autoclaving of biomass before hydrolysis had a minimal effect on mineral concentrations, and showed no significant effect on the two major sugars (glucose and xylose) found in these hydrolysates. However, autoclaving elevated the concentration of some furanic and phenolic compounds. Chemical genomics analyses using Saccharomyces cerevisiae strains indicated a high correlation between the AFEX-pretreated hydrolysates produced using these two methods within the same feedstock, indicating minimal differences between the autoclaving and antibiotic methods. Comparative fermentations with S. cerevisiae and Zymomonas mobilis also showed that autoclaving the AFEX-pretreated feedstocks had no significant effects on microbial performance in these hydrolysates. In conclusion, our results showed that autoclaving the pretreated feedstocks offered advantages over the addition of antibiotics for hydrolysate production. The autoclaving method produced a more consistent quality of hydrolysate.« less

40 CFR 63.9565 - What definitions apply to this subpart?

Code of Federal Regulations, 2013 CFR

2013-07-01

... limitation (including any operating limit) in this subpart during startup, shutdown, or malfunction.... Examples include hexane, toluene, and trichloroethylene. Initial startup means the first time that equipment is put into operation. Initial startup does not include operation solely for testing equipment...

40 CFR 63.9565 - What definitions apply to this subpart?

Code of Federal Regulations, 2012 CFR

2012-07-01

... limitation (including any operating limit) in this subpart during startup, shutdown, or malfunction.... Examples include hexane, toluene, and trichloroethylene. Initial startup means the first time that equipment is put into operation. Initial startup does not include operation solely for testing equipment...

40 CFR 63.9565 - What definitions apply to this subpart?

Code of Federal Regulations, 2014 CFR

2014-07-01

... limitation (including any operating limit) in this subpart during startup, shutdown, or malfunction.... Examples include hexane, toluene, and trichloroethylene. Initial startup means the first time that equipment is put into operation. Initial startup does not include operation solely for testing equipment...

40 CFR 63.9565 - What definitions apply to this subpart?

Code of Federal Regulations, 2011 CFR

2011-07-01

... limitation (including any operating limit) in this subpart during startup, shutdown, or malfunction.... Examples include hexane, toluene, and trichloroethylene. Initial startup means the first time that equipment is put into operation. Initial startup does not include operation solely for testing equipment...

75 FR 70963 - General Motors Corporation, Receipt of Petition for Decision of Inconsequential Noncompliance

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-19

..., as shown in the example set forth in Figure 1 in this standard. At the manufacturer's option, the... including the border surrounding the entire label, as shown in the example set forth in Figure 2 in this...), and, as appropriate, (h) and (i)) may be shown in the format and color scheme set forth in Figures 1...

Reconstruction and Nation Building Industry. Industry Study, Spring 2009

DTIC Science & Technology

2009-01-01

case of post-conflict operations (recent examples include Iraq, Afghanistan and Lebanon ). Particularly for smaller donors, working through the UN...justice models may have serious defects concerning gender equality, children’s rights, and forms of punishment that are prohibited under international... Lebanon provides an unfortunate example of a failed reconstruction in the 1990’s, which led to violence and a

28 CFR Appendix to Part 20 - Commentary on Selected Sections of the Regulations on Criminal History Record Information Systems

Code of Federal Regulations, 2014 CFR

2014-07-01

..., nor any recipient of assistance under the provisions of this title shall use or reveal any research or... would include, for example, the Office of Investigation of the Food and Drug Administration, which has.... The specific dispositions listed in this subsection are examples only and are not to be construed as...

28 CFR Appendix to Part 20 - Commentary on Selected Sections of the Regulations on Criminal History Record Information Systems

Code of Federal Regulations, 2010 CFR

2010-07-01

..., nor any recipient of assistance under the provisions of this title shall use or reveal any research or... would include, for example, the Office of Investigation of the Food and Drug Administration, which has.... The specific dispositions listed in this subsection are examples only and are not to be construed as...

28 CFR Appendix to Part 20 - Commentary on Selected Sections of the Regulations on Criminal History Record Information Systems

Code of Federal Regulations, 2013 CFR

2013-07-01

..., nor any recipient of assistance under the provisions of this title shall use or reveal any research or... would include, for example, the Office of Investigation of the Food and Drug Administration, which has.... The specific dispositions listed in this subsection are examples only and are not to be construed as...

28 CFR Appendix to Part 20 - Commentary on Selected Sections of the Regulations on Criminal History Record Information Systems

Code of Federal Regulations, 2012 CFR

2012-07-01

..., nor any recipient of assistance under the provisions of this title shall use or reveal any research or... would include, for example, the Office of Investigation of the Food and Drug Administration, which has.... The specific dispositions listed in this subsection are examples only and are not to be construed as...

28 CFR Appendix to Part 20 - Commentary on Selected Sections of the Regulations on Criminal History Record Information Systems

Code of Federal Regulations, 2011 CFR

2011-07-01

..., nor any recipient of assistance under the provisions of this title shall use or reveal any research or... would include, for example, the Office of Investigation of the Food and Drug Administration, which has.... The specific dispositions listed in this subsection are examples only and are not to be construed as...

34 CFR 403.111 - How must funds be used under the Secondary School Vocational Education Program and the...

Code of Federal Regulations, 2012 CFR

2012-07-01

... individuals who are members of special populations. Examples: Methods by which an eligible recipient may give... special populations include, but are not limited to, the following: Example 1: Method to give priority to...: Method to give priority to a limited number of program areas. Based on data from the preceding fiscal...

34 CFR 403.111 - How must funds be used under the Secondary School Vocational Education Program and the...

Code of Federal Regulations, 2014 CFR

2014-07-01

... individuals who are members of special populations. Examples: Methods by which an eligible recipient may give... special populations include, but are not limited to, the following: Example 1: Method to give priority to...: Method to give priority to a limited number of program areas. Based on data from the preceding fiscal...

34 CFR 403.111 - How must funds be used under the Secondary School Vocational Education Program and the...

Code of Federal Regulations, 2013 CFR

2013-07-01

... individuals who are members of special populations. Examples: Methods by which an eligible recipient may give... special populations include, but are not limited to, the following: Example 1: Method to give priority to...: Method to give priority to a limited number of program areas. Based on data from the preceding fiscal...

Strategic Planning in Higher Education: A Guide for Heads of Institutions, Senior Managers and Members of Governing Bodies.

ERIC Educational Resources Information Center

Higher Education Funding Council for England, Bristol.

This guide provides examples of good practice in strategic planning within higher education, particularly as it applies to Northern Ireland. Examples are drawn from the experiences of 13 case study universities and colleges. Sections of the report include a summary; an introduction and overview of the strategic planning process; and a discussion…

How Should Fifth-Grade Mathematics Teachers Start the School Year?: Relations between Teacher-Student Interactions and Mathematics Instruction over One Year

ERIC Educational Resources Information Center

Banse, Holland W.; Curby, Timothy W.; Palacios, Natalia A.; Rimm-Kaufman, Sara E.

2018-01-01

Background: Teaching is comprised of interconnected practices. Some practices are domain neutral (DN), or independent of a content area. Examples of DN practices include emotional and instructional support and classroom organization. Others are domain specific (DS), or content dependent. Within a mathematics context, examples of DS practices…

Pro-Apoptotic Breast Cancer Nanotherapeutics

DTIC Science & Technology

2013-07-01

Examples of nonspherical cell-penetrating particles existing in nature include the fila- mentous viruses such as the tobaccomosaic virus and the potato... virus X.4 Inspired by these examples from biology, Discher et al. have shown that cylindrical micelles have longer circulation times relative to...intended to create a protective corona around the assembled nanostructure, which would limit nonspecific adsorption of proteins and reduce proteolysis

Practical Comptrollership Course

DTIC Science & Technology

1987-03-01

variables that drive selection of "significant" areas. " Multilocation audits investigate specific functions. In 1985, for example, the NAS performed... audits of health care functions, and of supply departments, focusing on spare parts. These two audits were part of DoD-wide multilocation audit ...should have included more practical examples. Evaluator A questioned the inclusion of Chapter IIIE, addressing auditing , in the comptrollership course

Energy Decision Science and Informatics | Integrated Energy Solutions |

Science.gov Websites

Science Advanced decision science methods include multi-objective and multi-criteria decision support. Our decision science methods, including multi-objective and multi-criteria decision support. For example, we

Hemorrhoids

MedlinePlus

... by simply looking at the rectal area. External hemorrhoids can often be detected this way. Tests that may help diagnose the problem include: Rectal exam Sigmoidoscopy Anoscopy Treatment Treatments for hemorrhoids include: Over-the-counter corticosteroid (for example, cortisone) ...

Cholesterol Levels: What You Need to Know

MedlinePlus

... of saturated fats include some meats, dairy products, chocolate, baked goods, and deep-fried and processed foods. ... trans fats that you eat. Examples include the Therapeutic Lifestyle Changes diet and the DASH Eating Plan. ...

Meso-Mechanics and Meso-Structures: A Matter of Scale

NASA Technical Reports Server (NTRS)

Chamis, Christos C.; Gotsis, P. K.; Mital, S. K.

1998-01-01

Meso-mechanics and meso-structures are described in terms of the scales at which they are observed and formulated. Select composite examples are presented to illustrate that meso-mechanics and/or meso-structures are meaningful only when they refer to a specific scale in a hierarchical scale observation/simulation. These examples include different types of composite unit cells, woven fabric unit cells, and progressive fracture as a composite enhanced infrastructure made from reinforced concrete. The results from the select examples indicate that meso-mechanics and meso-structures are elusive terms and depend mainly on the investigators' knowledge and available information.

Space benefits: The secondary application of aerospace technology in other sectors of the economy

NASA Technical Reports Server (NTRS)

1980-01-01

Over 580 examples of the beneficial use of NASA aerospace technology by public and private organizations are described to demonstrate the effects of mission-oriented programs on technological progress in the United States. General observations regarding technology transfer activity are presented. Benefit cases are listed in 20 categories along with pertinent information such as communication link with NASA; the DRI transfer example file number and individual case numbers associated with the technology and examples used; and the date of the latest contract with user organizations. Subject, organization, geographic, and field center indexes are included.

Space Benefits: The secondary application of aerospace technology in other sectors of the economy

NASA Technical Reports Server (NTRS)

1981-01-01

Some 585 examples of the beneficial use of NASA aerospace technology by public and private organizations are described to demonstrate the effects of mission-oriented programs on technological progress in the United States. General observations regarding technology transfer activity are presented. Benefit cases are listed in 20 categories along with pertinent information such as communication link with NASA; the DRI transfer example file number; and individual case numbers associated with the technology and examples used; and the date of the latest contract with user organizations. Subject, organization, geographic, and field center indexes are included.

Implementing ethics in the professions: examples from environmental epidemiology.

PubMed

Soskolne, Colin L; Sieswerda, Lee E

2003-04-01

The need to integrate ethics into professional life, from the grassroots up, has been recognized, and a comprehensive ethics program has been proposed as a model. The model includes the four dimensions of: consensus building, ethics guidelines development and review, education, and implementation. The activities of the International Society for Environmental Epidemiology (ISEE) are presented as examples and compared with the proposed model. Several innovative activities are described and incentives for ethical professional conduct are highlighted. The examples are provided for emulation by other professional organizations in the hope that, thereby, greater protection of the public interest will be achieved.

Systems change resulting from HIV/AIDS education and training. A cross-cutting evaluation of nine innovative projects.

PubMed

Henderson, H; German, V F; Panter, A T; Huba, G J; Rohweder, C; Zalumas, J; Wolfe, L; Uldall, K K; Lalonde, B; Henderson, R; Driscoll, M; Martin, S; Duggan, S; Rahimian, A; Melchior, L A

1999-12-01

An evaluation of nine diverse HIV/AIDS training programs assessed the degree to which the programs produced changes in the ways that health care systems deliver HIV/AIDS care. Participants were interviewed an average of 8 months following completion of training and asked for specific examples of a resulting change in their health care system. More than half of the trainees gave at least one example of a systems change. The examples included the way patient referrals are made, the manner in which agency collaborations are organized, and the way care is delivered.

INCLUDING AORTIC VALVE MORPHOLOGY IN COMPUTATIONAL FLUID DYNAMICS SIMULATIONS: INITIAL FINDINGS AND APPLICATION TO AORTIC COARCTATION

PubMed Central

Wendell, David C.; Samyn, Margaret M.; Cava, Joseph R.; Ellwein, Laura M.; Krolikowski, Mary M.; Gandy, Kimberly L.; Pelech, Andrew N.; Shadden, Shawn C.; LaDisa, John F.

2012-01-01

Computational fluid dynamics (CFD) simulations quantifying thoracic aortic flow patterns have not included disturbances from the aortic valve (AoV). 80% of patients with aortic coarctation (CoA) have a bicuspid aortic valve (BAV) which may cause adverse flow patterns contributing to morbidity. Our objectives were to develop a method to account for the AoV in CFD simulations, and quantify its impact on local hemodynamics. The method developed facilitates segmentation of the AoV, spatiotemporal interpolation of segments, and anatomic positioning of segments at the CFD model inlet. The AoV was included in CFD model examples of a normal (tricuspid AoV) and a post-surgical CoA patient (BAV). Velocity, turbulent kinetic energy (TKE), time-averaged wall shear stress (TAWSS), and oscillatory shear index (OSI) results were compared to equivalent simulations using a plug inlet profile. The plug inlet greatly underestimated TKE for both examples. TAWSS differences extended throughout the thoracic aorta for the CoA BAV, but were limited to the arch for the normal example. OSI differences existed mainly in the ascending aorta for both cases. The impact of AoV can now be included with CFD simulations to identify regions of deleterious hemodynamics thereby advancing simulations of the thoracic aorta one step closer to reality. PMID:22917990

Responding to the Consequences of Climate Change

NASA Technical Reports Server (NTRS)

Hildebrand, Peter H.

2011-01-01

The talk addresses the scientific consensus concerning climate change, and outlines the many paths that are open to mitigate climate change and its effects on human activities. Diverse aspects of the changing water cycle on Earth are used to illustrate the reality climate change. These include melting snowpack, glaciers, and sea ice; changes in runoff; rising sea level; moving ecosystems, an more. Human forcing of climate change is then explained, including: greenhouse gasses, atmospheric aerosols, and changes in land use. Natural forcing effects are briefly discussed, including volcanoes and changes in the solar cycle. Returning to Earth's water cycle, the effects of climate-induced changes in water resources is presented. Examples include wildfires, floods and droughts, changes in the production and availability of food, and human social reactions to these effects. The lk then passes to a discussion of common human reactions to these forecasts of climate change effects, with a summary of recent research on the subject, plus several recent historical examples of large-scale changes in human behavior that affect the climate and ecosystems. Finally, in the face for needed action on climate, the many options for mitigation of climate change and adaptation to its effects are presented, with examples of the ability to take affordable, and profitable action at most all levels, from the local, through national.

Using protistan examples to dispel the myths of intelligent design.

PubMed

Farmer, Mark A; Habura, Andrea

2010-01-01

In recent years the teaching of the religiously based philosophy of intelligent design (ID) has been proposed as an alternative to modern evolutionary theory. Advocates of ID are largely motivated by their opposition to naturalistic explanations of biological diversity, in accordance with their goal of challenging the philosophy of scientific materialism. Intelligent design has been embraced by a wide variety of creationists who promote highly questionable claims that purport to show the inadequacy of evolutionary theory, which they consider to be a threat to a theistic worldview. We find that examples from protistan biology are well suited for providing evidence of many key evolutionary concepts, and have often been misrepresented or roundly ignored by ID advocates. These include examples of adaptations and radiations that are said to be statistically impossible, as well as examples of speciation both in the laboratory and as documented in the fossil record. Because many biologists may not be familiar with the richness of the protist evolution dataset or with ID-based criticisms of evolution, we provide examples of current ID arguments and specific protistan counter-examples.

Applied Astronomy: An Optical Survey for Space Debris at GEO

NASA Technical Reports Server (NTRS)

Seitzer, Patrick; Barker, Edwin S.; Abercromby, K.; Rodriquez, H.

2007-01-01

A viewgraph is presented to discuss space debris at Geosynchronous Earth Orbit (GEO). The topics include: 1) Syncom1 launched February 14, 1963 Failed on orbit insertion 1st piece of GEO debris!; 2) Example of recent GEO payload: XM-2 Rock satellite for direct broadcast radio; 3) MODEST Michigan Orbital DEbrisSurvey Telescope the telescope formerly known as the Curtis-Schmidt; 4) GEO Debris Survey; 5) Examples of Detections; 6) Brightness Variations Common; 7) Observed Angular Rates; 8) Two Populations at GEO; 9) High Area-to-Mass Ratio Material (A/M); 10) Examples of MLI; 11) Examples of MLI Release in LEO; 12) Liou & Weaver (2005) models; 13) ESA 1-m Telescope Survey; 14) Two Telescopes March 2007 Survey and Follow-up; 15) Final Eccentricity; and 16) How control Space Debris?

Ore Deposits Mined for Critical Elements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Verplanck, Philip; Kelley, Karen

Summary of deposit types containing critical elements, including, cobalt, gallium, germanium, indium, niobium, PGE, REE, rhenium, selenium, and tellurium. Includes information about ore deposit type, mineralogy, geologic setting, example deposits and districts, concentration ranges per reported resource, grade, and additional deposit notes. References are also included.

Electric current-producing device having sulfone-based electrolyte

DOEpatents

Angell, Charles Austen; Sun, Xiao-Guang

2010-11-16

Electrolytic solvents and applications of such solvents including electric current-producing devices. For example, a solvent can include a sulfone compound of R1--SO2--R2, with R1 being an alkyl group and R2 a partially oxygenated alkyl group, to exhibit high chemical and thermal stability and high oxidation resistance. For another example, a battery can include, between an anode and a cathode, an electrolyte which includes ionic electrolyte salts and a non-aqueous electrolyte solvent which includes a non-symmetrical, non-cyclic sulfone. The sulfone has a formula of R1--SO2--R2, wherein R1 is a linear or branched alkyl or partially or fully fluorinated linear or branched alkyl group having 1 to 7 carbon atoms, and R2 is a linear or branched or partially or fully fluorinated linear or branched oxygen containing alkyl group having 1 to 7 carbon atoms. The electrolyte can include an electrolyte co-solvent and an electrolyte additive for protective layer formation.

Criteria of validity for animal models of psychiatric disorders: focus on anxiety disorders and depression

PubMed Central

2011-01-01

Animal models of psychiatric disorders are usually discussed with regard to three criteria first elaborated by Willner; face, predictive and construct validity. Here, we draw the history of these concepts and then try to redraw and refine these criteria, using the framework of the diathesis model of depression that has been proposed by several authors. We thus propose a set of five major criteria (with sub-categories for some of them); homological validity (including species validity and strain validity), pathogenic validity (including ontopathogenic validity and triggering validity), mechanistic validity, face validity (including ethological and biomarker validity) and predictive validity (including induction and remission validity). Homological validity requires that an adequate species and strain be chosen: considering species validity, primates will be considered to have a higher score than drosophila, and considering strains, a high stress reactivity in a strain scores higher than a low stress reactivity in another strain. Pathological validity corresponds to the fact that, in order to shape pathological characteristics, the organism has been manipulated both during the developmental period (for example, maternal separation: ontopathogenic validity) and during adulthood (for example, stress: triggering validity). Mechanistic validity corresponds to the fact that the cognitive (for example, cognitive bias) or biological mechanisms (such as dysfunction of the hormonal stress axis regulation) underlying the disorder are identical in both humans and animals. Face validity corresponds to the observable behavioral (ethological validity) or biological (biomarker validity) outcomes: for example anhedonic behavior (ethological validity) or elevated corticosterone (biomarker validity). Finally, predictive validity corresponds to the identity of the relationship between the triggering factor and the outcome (induction validity) and between the effects of the treatments on the two organisms (remission validity). The relevance of this framework is then discussed regarding various animal models of depression. PMID:22738250

Choosing estimands in clinical trials with missing data.

PubMed

Mallinckrodt, Craig; Molenberghs, Geert; Rathmann, Suchitrita

2017-01-01

Recent research has fostered new guidance on preventing and treating missing data. Consensus exists that clear objectives should be defined along with the causal estimands; trial design and conduct should maximize adherence to the protocol specified interventions; and a sensible primary analysis should be used along with plausible sensitivity analyses. Two general categories of estimands are effects of the drug as actually taken (de facto, effectiveness) and effects of the drug if taken as directed (de jure, efficacy). Motivated by examples, we argue that no single estimand is likely to meet the needs of all stakeholders and that each estimand has strengths and limitations. Therefore, stakeholder input should be part of an iterative study development process that includes choosing estimands that are consistent with trial objectives. To this end, an example is used to illustrate the benefit from assessing multiple estimands in the same study. A second example illustrates that maximizing adherence reduces sensitivity to missing data assumptions for de jure estimands but may reduce generalizability of results for de facto estimands if efforts to maximize adherence in the trial are not feasible in clinical practice. A third example illustrates that whether or not data after initiation of rescue medication should be included in the primary analysis depends on the estimand to be tested and the clinical setting. We further discuss the sample size and total exposure to placebo implications of including post-rescue data in the primary analysis. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Invaginating Structures in Mammalian Synapses

PubMed Central

Petralia, Ronald S.; Wang, Ya-Xian; Mattson, Mark P.; Yao, Pamela J.

2018-01-01

Invaginating structures at chemical synapses in the mammalian nervous system exist in presynaptic axon terminals, postsynaptic spines or dendrites, and glial processes. These invaginating structures can be divided into three categories. The first category includes slender protrusions invaginating into axonal terminals, postsynaptic spines, or glial processes. Best known examples of this category are spinules extending from postsynaptic spines into presynaptic terminals in forebrain synapses. Another example of this category are protrusions from inhibitory presynaptic terminals invaginating into postsynaptic neuronal somas. Regardless of the direction and location, the invaginating structures of the first category do not have synaptic active zones within the invagination. The second category includes postsynaptic spines invaginating into presynaptic terminals, whereas the third category includes presynaptic terminals invaginating into postsynaptic spines or dendrites. Unlike the first category, the second and third categories have active zones within the invagination. An example of the second category are mossy terminal synapses of the hippocampal CA3 region, in which enlarged spine-like structures invaginate partly or entirely into mossy terminals. An example of the third category is the neuromuscular junction (NMJ) where substantial invaginations of the presynaptic terminals invaginate into the muscle fibers. In the retina, rod and cone synapses have invaginating processes from horizontal and bipolar cells. Because horizontal cells act both as post and presynaptic structures, their invaginating processes represent both the second and third category. These invaginating structures likely play broad yet specialized roles in modulating neuronal cell signaling. PMID:29674962

Cataloging Expert Systems: Optimism and Frustrated Reality.

ERIC Educational Resources Information Center

Olmstadt, William J.

2000-01-01

Discusses artificial intelligence and attempts to catalog expert systems. Topics include the nature of expertise; examples of cataloging expert systems; barriers to implementation; and problems, including total automation, cataloging expertise, priorities, and system design. (LRW)

Rewards and Performance Incentives.

ERIC Educational Resources Information Center

Zigon, Jack

1994-01-01

Discusses rewards and performance incentives for employees, including types of rewards; how rewards help in managing; dysfunctional awards; selecting the right reward; how to find rewards that fit; and delivering rewards effectively. Examples are included. (three references) (LRW)

Overview of Chemicals of Emerging Concern

EPA Science Inventory

Contaminants of emerging concern or environmental emerging contaminants, are chemicals, products and materials that are detected with increasing frequency in all environmental media including surface, ground water and drinking water. Examples of these contaminants include pharmac...

TIGER: the universal biosensor

NASA Astrophysics Data System (ADS)

Hofstadler, Steven A.; Sampath, Rangarajan; Blyn, Lawrence B.; Eshoo, Mark W.; Hall, Thomas A.; Jiang, Yun; Drader, Jared J.; Hannis, James C.; Sannes-Lowery, Kristin A.; Cummins, Lendell L.; Libby, Brian; Walcott, Demetrius J.; Schink, Amy; Massire, Christian; Ranken, Raymond; Gutierrez, Jose; Manalili, Sheri; Ivy, Cristina; Melton, Rachael; Levene, Harold; Barrett-Wilt, Greg; Li, Feng; Zapp, Vanessa; White, Neill; Samant, Vivek; McNeil, John A.; Knize, Duane; Robbins, David; Rudnick, Karl; Desai, Anjali; Moradi, Emily; Ecker, David J.

2005-03-01

In this work, we describe a strategy for the detection and characterization of microorganisms associated with a potential biological warfare attack or a natural outbreak of an emerging infectious disease. This approach, termed TIGER (Triangulation Identification for the Genetic Evaluation of Risks), relies on mass spectrometry-derived base composition signatures obtained from PCR amplification of broadly conserved regions of the microbial genome(s) in a sample. The sample can be derived from air filtration devices, clinical samples, or other sources. Core to this approach are "intelligent PCR primers" that target broadly conserved regions of microbial genomes that flank variable regions. This approach requires that high-performance mass measurements be made on PCR products in the 80-140 bp size range in a high-throughput, robust modality. As will be demonstrated, the concept is equally applicable to bacteria and viruses and could be further applied to fungi and protozoa. In addition to describing the fundamental strategy of this approach, several specific examples of TIGER are presented that illustrate the impact this approach could have on the way biological weapons attacks are detected and the way that the etiologies of infectious diseases are determined. The first example illustrates how any bacterial species might be identified, using Bacillus anthracis as the test agent. The second example demonstrates how DNA-genome viruses are identified using five members of Poxviridae family, whose members includes Variola virus, the agent responsible for smallpox. The third example demonstrates how RNA-genome viruses are identified using the Alphaviruses (VEE, WEE, and EEE) as representative examples. These examples illustrate how the TIGER technology can be applied to create a universal identification strategy for all pathogens, including those that infect humans, livestock, and plants.

A Descriptive Outline of a Modular Schedule, Flexible Scheduling Using the Data Processing Method. A Report from Virgin Valley High School, Mesquite, Nevada.

ERIC Educational Resources Information Center

Allan, Blaine W., Comp.

The procedures, forms, and philosophy of the computerized modular scheduling program developed at Virgin Valley High School are outlined. The modular concept is eveloped as a new approach to course structure with explanations, examples, and worksheets included. Examples of courses of study, input information for the data processing center, output…

Development and Use of Numerical and Factual Data Bases

DTIC Science & Technology

1983-10-01

the quantitative description of what has been accomplished by their scientific and technical endeavors. 1-3 overhead charge to the national treasury... Molecular properties calculated with the aid of quantum mechanics or the prediction of solar eclipses using celestial mechanics are examples of theoretical...system under study. Examples include phase diagrams, molecular models, geological maps, metabolic pathways. Symbolic data (F3) are data presented in

Harvesting contaminants from liquid

DOEpatents

Simpson, John T.; Hunter, Scott R.

2016-05-31

Disclosed are examples of apparatuses for evaporative purification of a contaminated liquid. In each example, there is a vessel for storing the contaminated fluid. The vessel includes a surface coated with a layer of superhydrophobic material and the surface is at least partially in contact with the contaminated liquid. The contaminants do not adhere to the surface as the purified liquid evaporates, thus allowing the contaminants to be harvested.

Biologically-Inspired Deceptive Behavior for a Robot

DTIC Science & Technology

2012-01-01

by sending false signals either intentionally or unintentionally, are essential for animals’ survival. For example, camouflage and mimicry are well...detection by both predators and their prey. While camouflage or mimicry are examples of unknowingly deceiving, a deceptive behavior can include...face this situation, where it is important to discourage an adversary from discovering a protected site, so the application of these bio -inspired

Device for calorimetric measurement

DOEpatents

King, William P; Lee, Jungchul

2015-01-13

In one aspect, provided herein is a single crystal silicon microcalorimeter, for example useful for high temperature operation and long-term stability of calorimetric measurements. Microcalorimeters described herein include microcalorimeter embodiments having a suspended structure and comprising single crystal silicon. Also provided herein are methods for making calorimetric measurements, for example, on small quantities of materials or for determining the energy content of combustible material having an unknown composition.

Systems and Methods for Composable Analytics

DTIC Science & Technology

2014-04-29

simplistic module that performs a mathematical operation on two numbers. The most important method is the Execute() method. This will get called when it is...addition, an input control is also specified in the example below. In this example, the mathematical operator can only be chosen from a preconfigured...approaches. Some of the industries that could benefit from Composable Analytics include pharmaceuticals, health care, insurance, actuaries , and

Empowering Globally Integrated Operations and Mission Command: Revisiting Key West

DTIC Science & Technology

2013-03-01

depended on coordination between commanders. Examples include Captain Thomas McDonough’s 4 U.S...Hedgehog Concept In his book, Good to Great, which describes how good organizations become great ones, Jim Collins borrows an example from an Isaiah ...that it executes with perfection—curling into a ball with its spikes outward. 62 In the words of Archilochus (first line in quotes), Isaiah Berlin

Hydrolysis of Surfactants Containing Ester Bonds: Modulation of Reaction Kinetics and Important Aspects of Surfactant Self-Assembly

ERIC Educational Resources Information Center

Lundberg, Dan; Stjerndahl, Maria

2011-01-01

The effects of self-assembly on the hydrolysis kinetics of surfactants that contain ester bonds are discussed. A number of examples on how reaction rates and apparent reaction orders can be modulated by changes in the conditions, including an instance of apparent zero-order kinetics, are presented. Furthermore, it is shown that the examples on…

Red River chloride remote sensing study

NASA Technical Reports Server (NTRS)

1975-01-01

Side looking radar, infrared thermal imagery and color photography, together with a few examples of black and white panoramic photos, are used to supplement information on the natural saline pollution problem that is hydrologically and geologically oriented. The study area was explored concurrently by ground methods and a reasonably good understanding of hydrogeological conditions has been achieved. Examples of the products acquired, their interpretation, and use techniques are included.

Teaching with Games: Online Resources and Examples for Entry Level Courses

NASA Astrophysics Data System (ADS)

Teed, R.; Manduca, C.

2004-12-01

Using games to teach introductory geoscience can motivate students to enthusiastically learn material that they might otherwise condemn as "boring". A good educational game is one that immerses the players in the material and engages them for as long as it takes to master that material. There are some good geoscience games already available, but instructors can also create their own, suitable to their students and the content that they are teaching. Game-Based Learning is a module on the Starting Point website for faculty teaching entry level geosciences. It assists faculty in using games in their teaching by providing a description of the features of game-based learning, why you would use it, how to use games to teach geoscience, examples, and references. Other issues discussed include the development of video games for teaching, having your students create educational games, what makes a good game, handling competition in the classroom, and grading. The examples include descriptions of and rules for a GPS treasure hunt, a geology quiz show, and an earthquake game, as well as links to several online geological video games, and advice on how to design a paleontology board game. Starting Point is intended to help both experienced faculty and new instructors meet the challenge of teaching introductory geoscience classes, including environmental science and oceanography as well as more traditional geology classes. For many students, these classes are both the first and the last college-level science class that they will ever take. They need to learn enough about the Earth in that one class to sustain them for many decades as voters, consumers, and sometimes even as teachers. Starting Point is produced by a group of authors working with the Science Education Resource Center. It contains dozens of detailed examples categorized by geoscience topic with advice about using them and assessing learning. Each example is linked to one of many modules, such as Game-Based Learning, Interactive Lectures, or Using an Earth History Approach. These modules describe teaching tools and techniques, provide examples and advice about using them in an introductory geoscience class, and give instructors details on how to create their own exercises.

Designing worked examples for learning tangent lines to circles

NASA Astrophysics Data System (ADS)

Retnowati, E.; Marissa

2018-03-01

Geometry is a branch of mathematics that deals with shape and space, including the circle. A difficult topic in the circle may be the tangent line to circle. This is considered a complex material since students have to simultaneously apply several principles to solve the problems, these are the property of circle, definition of the tangent, measurement and Pythagorean theorem. This paper discusses designs of worked examples for learning tangent line to circles and how to apply this design to an effective and efficient instructional activity. When students do not have sufficient prior knowledge, solving tangent problems might be clumsy, and as a consequence, the problem-solving activity hinders learning. According to a Cognitive Load Theory, learning occurs when students can construct new knowledge based on the relevant knowledge previously learned. When the relevant knowledge is unavailable, providing students with the worked example is suggested. Worked example may reduce unproductive process during learning that causes extraneous cognitive load. Nevertheless, worked examples must be created in such a way facilitate learning.

20 CFR 901.11 - Enrollment procedures.

Code of Federal Regulations, 2011 CFR

2011-04-01

.... Examples include economics, computer programs, pension accounting, investment and finance, risk theory... Columbia responsible for the issuance of a license in the field of actuarial science, insurance, accounting... include economics, computer programming, pension accounting, investment and finance, risk theory...

Discrete-Event Simulation in Chemical Engineering.

ERIC Educational Resources Information Center

Schultheisz, Daniel; Sommerfeld, Jude T.

1988-01-01

Gives examples, descriptions, and uses for various types of simulation systems, including the Flowtran, Process, Aspen Plus, Design II, GPSS, Simula, and Simscript. Explains similarities in simulators, terminology, and a batch chemical process. Tables and diagrams are included. (RT)

When Should Zero Be Included on a Scale Showing Magnitude?

ERIC Educational Resources Information Center

Kozak, Marcin

2011-01-01

This article addresses an important problem of graphing quantitative data: should one include zero on the scale showing magnitude? Based on a real time series example, the problem is discussed and some recommendations are proposed.

The analysis of 3-phase squirrel-cage induction motors including space harmonics and mutual slotting in transient and steady state

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paap, G.C.

1991-03-01

From general equations which describe the transient electromechanical behavior of the asynchronous squirrel-cage motor, and which include the influence of space harmonics and mutual slotting, simplified models are derived and compared. The models derived are demonstrated in examples where special attention is paid to the influence of the place of the harmonics in the mutual inductance matrix and the influence of mutual slotting. Further, the steady-state equations are derived and the back-transformation for the stator and rotor currents is given. One example is compared with the result of measurements.

Consistency Across Standards or Standards in a New Business Model

NASA Technical Reports Server (NTRS)

Russo, Dane M.

2010-01-01

Presentation topics include: standards in a changing business model, the new National Space Policy is driving change, a new paradigm for human spaceflight, consistency across standards, the purpose of standards, danger of over-prescriptive standards, a balance is needed (between prescriptive and general standards), enabling versus inhibiting, characteristics of success-oriented standards, characteristics of success-oriented standards, and conclusions. Additional slides include NASA Procedural Requirements 8705.2B identifies human rating standards and requirements, draft health and medical standards for human rating, what's been done, government oversight models, examples of consistency from anthropometry, examples of inconsistency from air quality and appendices of government and non-governmental human factors standards.

Application of Density Functional Theory to Systems Containing Metal Atoms

NASA Technical Reports Server (NTRS)

Bauschlicher, Charles W., Jr.

2006-01-01

The accuracy of density functional theory (DFT) for problems involving metal atoms is considered. The DFT results are compared with experiment as well as results obtained using the coupled cluster approach. The comparisons include geometries, frequencies, and bond energies. The systems considered include MO2, M(OH)+n, MNO+, and MCO+2. The DFT works well for frequencies and geometries, even in case with symmetry breaking; however, some examples have been found where the symmetry breaking is quite severe and the DFT methods do not work well. The calculation of bond energies is more difficult and examples of successes as well as failures of DFT will be given.

Engineering issues for hand-held sensing devices, with examples

NASA Astrophysics Data System (ADS)

Freiwald, David A.; Freiwald, Joyce

1994-03-01

It is now U.S. defense policy that there will be no new platform starts. The emphasis for platforms will be on O&M cost reduction, life-extension improvements, and force-multiplier- device upgrades. There is also an increasing emphasis on hand-held force-multiplier devices for individuals, which is the focus of this paper. Engineering issues include operations analysis, weight, cube, cost, prime power, ease of use, data storage, reliability, fault tolerance, data communications and human factors. Two examples of hand-held devices are given. Applications include USMC, Army, SOCOM, DEA, FBI, SS, Border Patrol and others. Barriers to adoption of such technology are also discussed.

Response Surface Modeling of Combined-Cycle Propulsion Components using Computational Fluid Dynamics

NASA Technical Reports Server (NTRS)

Steffen, C. J., Jr.

2002-01-01

Three examples of response surface modeling with CFD are presented for combined cycle propulsion components. The examples include a mixed-compression-inlet during hypersonic flight, a hydrogen-fueled scramjet combustor during hypersonic flight, and a ducted-rocket nozzle during all-rocket flight. Three different experimental strategies were examined, including full factorial, fractionated central-composite, and D-optimal with embedded Plackett-Burman designs. The response variables have been confined to integral data extracted from multidimensional CFD results. Careful attention to uncertainty assessment and modeling bias has been addressed. The importance of automating experimental setup and effectively communicating statistical results are emphasized.

Architectures for Human Exploration of Near Earth Asteroids

NASA Technical Reports Server (NTRS)

Drake, Bret G.

2011-01-01

The presentation explores human exploration of Near Earth Asteroid (NEA) key factors including challenges of supporting humans for long-durations in deep-space, incorporation of advanced technologies, mission design constraints, and how many launches are required to conduct a round trip human mission to a NEA. Topics include applied methodology, all chemical NEA mission operations, all nuclear thermal propulsion NEA mission operations, SEP only for deep space mission operations, and SEP/chemical hybrid mission operations. Examples of mass trends between datasets are provided as well as example sensitivity of delta-v and trip home, sensitivity of number of launches and trip home, and expected targets for various transportation architectures.

Ray tracing a three-dimensional scene using a hierarchical data structure

DOEpatents

Wald, Ingo; Boulos, Solomon; Shirley, Peter

2012-09-04

Ray tracing a three-dimensional scene made up of geometric primitives that are spatially partitioned into a hierarchical data structure. One example embodiment is a method for ray tracing a three-dimensional scene made up of geometric primitives that are spatially partitioned into a hierarchical data structure. In this example embodiment, the hierarchical data structure includes at least a parent node and a corresponding plurality of child nodes. The method includes a first act of determining that a first active ray in the packet hits the parent node and a second act of descending to each of the plurality of child nodes.

Statement No. 13: Timing differences pertaining to third-party payments. Healthcare Financial Management Association, Principles and Practices Board.

PubMed

1992-01-01

As this statement describes, institutional healthcare providers have recorded timing differences and continue to be confronted with circumstances warranting their recording. Medicare arrangements for paying for capital related cost are the most frequent basis of recording or changing previously recorded timing differences but other bases for recording or changing previously recorded timing differences are described in this statement. As this statement was being prepared for publication, another significant change in Medicare arrangements for paying for capital-related cost was under consideration. This statement is intended to describe the issue of timing differences generally and not to focus only on changes called for by a single legislative or regulatory action. Furthermore, the disposition of the currently proposed change is uncertain. Accordingly, the examples included in the appendices of this statement are the same as were included in the exposure draft of this statement released in 1990. HFMA has indicated its intent to prepare examples of the recording of changes in timing differences called for by legislation or regulations when the terms are sufficiently certain to warrant action. Those examples will be based on the conclusions included in this statement.

Targeting as a Mode of Science Communication: Principles, Issues and a Practical Example

NASA Astrophysics Data System (ADS)

Holland, G. J.; Vigh, J. L.

2011-12-01

Today's media landscape contains a rich and diverse range of communications opportunities. New media, such as the internet, blogosphere and social networks, are complementing, supplementing and also replacing the traditional mass media communications through print, radio and television. This diversification certainly contains pitfalls and difficulties as has been demonstrated in the Climategate affair. But there are also real opportunities for utilizing the diversity to provide targeted science communications that are framed in the context of the specific group of interest. That such targeting of audience attitudes and beliefs is an important key to effective science communications has been demonstrated by, for example, Leiserowitz, Maibach et al (2009). This approach does require an understanding of the audience and a careful framing of the message in terms familiar to the targeted group. Here many factors come into play, including: including immediacy, economics, culture, community leaders, emotional framing, and ideological filters. In this talk we shall elaborate on the principles, issues and opportunities. A practical example of working with the religious community on communicating the science of climate change will also be presented. This will include the approach adopted, progress to date and the lessons learnt.

It's, Like, Relative Motion at the Mall

NASA Astrophysics Data System (ADS)

Robinett, R. W.

2003-03-01

Almost all introductory textbooks, both algebra- and calculus-based, include sections on relative motion and relative velocity, in both one and two dimensions. The most popular examples in discussions of 2-D relative velocity in such texts seem to be the motion of airplanes/blimps flying in the presence of wind or the conceptually identical cases of boats/rafts piloted across rivers/streams, including the effects of currents. These and similar cases are rather removed from the everyday experience of some students, and the use of simple lecture demonstrations to illustrate these concepts can be quite useful. For example, the motion of a simple toy "wind-up" car moving at constant speed across a horizontal tabletop, with a plastic sheet underneath providing the "moving frame of reference," can illustrate many aspects of such problems, including the need to "point" the plane/boat in an appropriate direction, just as illustrated in many textbook figures. On the other hand, it is also useful if students can directly experience concepts for themselves, especially in a kinesthetic manner, but there are seemingly far fewer human-sized lecture demonstrations on this topic. In this paper, we will point out one such example which might well be just a short drive away.