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Sample records for zymomonas mobilis structural

  1. Biochemical and genetic improvement of Zymomonas mobilis

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    Ingram, L O; Carey, V C; Dombek, K M; Holt, A S; Holt, W A; Osman, Y A; Walia, S K

    1984-01-01

    Zymomonas mobilis offers many advantages for alcohol production including three- to five-fold higher rates of substrate conversion. Current progress and approaches are discussed for the biochemical and genetic improvement of this organism. These include the isolation of salt-resistant mutants and low pH-tolerant mutants. Gene banks of Lactobacillus heterohiochi are being screened for genes encoding alcohol resistance which can be subsequently introduced into Zymomonas mobilis. In addition, an enteric lactose operon has been inserted into Zymomonas mobilis and is expressed. These new strains are being further modified to increase the substrate range of Zymomonas mobilis to include lactose. This lactose operon serves as a model system to investigate the expression of foreign genes in Zymomonas mobilis. 25 references.

  2. Formation of ethanol from lactose by Zymomonas mobilis

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    Goodman, A E; Strzelecki, A T; Rogers, P L

    1984-01-01

    The lactose transposon Tn951 on the IncP plasmid RP1, was introduced into a strain of Zymomonas mobilis. The lac Z gene was expressed and US -galactosidase was produced. The synthesis of US -galactosidase was induced by either isopropyl-US -D-thiogalactopyranoside or lactose, and was not sensitive to catabolite repression. Cells of Zymomonas mobilis containing Tn951 were unable to form colonies on lactose plates, but in liquid medium produced ethanol from lactose as the sole carbon source. The original strain of Zymomonas mobilis without Tn951 produced little or no US -galactosidase and was unable to produce ethanol from lactose in liquid medium.

  3. Modelling of the metabolism of Zymomonas mobilis growing on a defined medium

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    Posten, C

    1989-08-07

    A structured model of Zymomonas mobilis is presented using fermentation data of a defined aspartate medium. After some remarks on the structure of the metabolism the model is derived by considering sub-models, e.g. balance equations, and by identifying the unknown parameters separately for each sub-model. Some results are the elemental composition of Zymomonas mobilis, a description of the substrate uptake during substrate limitation and the growth inhibition during substrate saturation. The results are shown as simulation and are discussed in relation to the inhibitory effect of ethanol on the bacterial cell. (orig.).

  4. Ethanol production from soybean molasses by Zymomonas mobilis

    International Nuclear Information System (INIS)

    Letti, Luiz Alberto Junior; Karp, Susan Grace; Woiciechowski, Adenise Lorenci; Soccol, Carlos Ricardo

    2012-01-01

    This work deals with the utilization of soybean molasses (a low cost byproduct) to produce ethanol, an important biofuel, using the microorganism Zymomonas mobilis NRRL 806, a gram negative bacterium. At the first part of the work, laboratorial scale tests, using 125 mL flasks were performed to evaluate the effect of three variables on ethanol production: soybean molasses concentration (the sole carbon and nitrogen source), pH and period of previous aerobial phase. The optimal soybean concentration was around 200 g L -1 of soluble solids, pH between 6.0 and 7.0, and the period of previous aerobial phase did not provide significant effect. At the second part, kinetic tests were performed to compare the fermentation yields of Zymomonas mobilis NRRL 806 in flasks and in a bench scale batch reactor (it was obtained respectively 78.3% and 96.0% of the maximum theoretical yields, with productions of 24.2 and 29.3 g L -1 of ethanol). The process with a reactor fermentation using Saccharomyces cerevisiae LPB1 was also tested (it was reached 89.3% of the theoretical maximum value). A detailed kinetic behavior of the molasses sugars metabolism for Z. mobilis was also shown, either in reactor or in flasks. This work is a valuable tool for further works in the subject of ethanol production from agro-industrial by-products. -- Highlights: ► Zymomonas mobilis was able to grow and produce ethanol on diluted soybean molasses. ► Best conditions for ethanol production:200g L -1 of soluble solids; pH around 6,5. ► Z. mobilis had better ethanol production and yield when compared to S. cerevisiae. ► In reactor, Z. mobilis produced 29.3 g L -1 of ethanol, 96.0% of the maximum yield.

  5. Crystal structure of cbbF from Zymomonas mobilis and its functional implication

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    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 and 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.

  6. OPTIMASI FERMENTASI BAGAS TEBU OLEH Zymomonas mobilis CP4 (NRRL B-14023 UNTUK PRODUKSI BIOETANOL (Optimization of Sugarcane Bagasse Fermentation by Zymomonas mobilis CP4 (NRRL B-14023 for Bioethanol Production

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    Atmiral Ernes

    2014-10-01

    (v/v. Berdasarkan hasil penelitian, kadar etanol optimal diperoleh sebesar 1,213% (v/v, yang menunjukkan hasil yang tidak berbeda jauh dengan prediksi model. Yield etanol yang diperoleh sebesar 0,479 dengan efi siensi fermentasi 93,9%. Hasil penelitian ini membuktikan bahwa strain bakteri Zymomonas mobilis CP4 memiliki potensi yang cukup menjanjikan sebagai mikroba penghasil etanol. Kata kunci: Bioetanol, bagas tebu, Zymomonas mobilis CP4, optimasi fermentasi

  7. Ethanologenic Enzymes of Zymomonas mobilis

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    Ingram, Lonnie O' Neal

    1999-03-01

    Zymomonas mobilis is a unique microorganism in being both obligately fermentative and utilizing a Entner-Doudoroff pathway for glycolysis. Glycolytic flux in this organism is readily measured as evolved carbon dioxide, ethanol, or glucose consumed and exceeds 1 {micro}mole glucose/min per mg cell protein. To support this rapid glycolysis, approximately 50% of cytoplasmic protein is devoted to the 13 glycolytic and fermentative enzymes which constitute this central catabolic pathway. Only 1 ATP (net) is produced from each glucose metabolized. During the past grant period, we have completed the characterization of 11 of the 13 glycolytic genes from Z. mobilis together with complementary but separate DOE-fimded research by a former post-dot and collaborator, Dr. Tyrrell Conway. Research funded in my lab by DOE, Division of Energy Biosciences can be divided into three sections: A. Fundamental studies; B. Applied studies and utility; and C. Miscellaneous investigations.

  8. Zymomonas mobilis for fuel ethanol and higher value products.

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    Rogers, P L; Jeon, Y J; Lee, K J; Lawford, H G

    2007-01-01

    High oil prices, increasing focus on renewable carbohydrate-based feedstocks for fuels and chemicals, and the recent publication of its genome sequence, have provided continuing stimulus for studies on Zymomonas mobilis. However, despite its apparent advantages of higher yields and faster specific rates when compared to yeasts, no commercial scale fermentations currently exist which use Z. mobilis for the manufacture of fuel ethanol. This may change with the recent announcement of a Dupont/Broin partnership to develop a process for conversion of lignocellulosic residues, such as corn stover, to fuel ethanol using recombinant strains of Z. mobilis. The research leading to the construction of these strains, and their fermentation characteristics, are described in the present review. The review also addresses opportunities offered by Z. mobilis for higher value products through its metabolic engineering and use of specific high activity enzymes.

  9. Zymomonas mobilis: a bacterium for ethanol production

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    Baratti, J.C.; Bu' Lock, J.D.

    1986-01-01

    Zymomonas mobilis is a facultative anaerobic gram negative bacterium first isolated in tropical countries from alcoholic beverages like the African palm wine, the Mexican pulque and also as a contaminant of cider (cider sickness) or beer in the European countries. It is one of the few facultative anaerobic bacteria degrading glucose by the Entner-Doudoroff pathway usually found in strictly aerobic microorganisms. Some work was devoted to this bacterium in the 50s and 60s and was reviewed by Swings and De Ley in their classical paper published in 1977. During the 70s there was very little work on the bacterium until 1979 and the first report by the Australian group of P.L. Rogers on the great potentialities of Z. mobilis for ethanol production. At that time the petroleum crisis had led the developed countries to search for alternative fuel from renewable resources. The Australian group clearly demonstrated the advantages of the bacterium compared to the yeasts traditionally used for the alcoholic fermentation. As a result, there was a considerable burst in the Zymomonas literature which started from nearly zero in the late 70s to attain 70 papers published in the field in 1984. In this article, papers published from 1982 to 1986 are reviewed.

  10. Transcriptome profiling of Zymomonas mobilis under furfural stress.

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    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.

  11. Zymomonas mobilis: a novel platform for future biorefineries.

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    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.

  12. Advances and prospects in metabolic engineering of Zymomonas mobilis.

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    Wang, Xia; He, Qiaoning; Yang, Yongfu; Wang, Jingwen; Haning, Katie; Hu, Yun; Wu, Bo; He, Mingxiong; Zhang, Yaoping; Bao, Jie; Contreras, Lydia M; Yang, Shihui

    2018-04-05

    Biorefinery of biomass-based biofuels and biochemicals by microorganisms is a competitive alternative of traditional petroleum refineries. Zymomonas mobilis is a natural ethanologen with many desirable characteristics, which makes it an ideal industrial microbial biocatalyst for commercial production of desirable bioproducts through metabolic engineering. In this review, we summarize the metabolic engineering progress achieved in Z. mobilis to expand its substrate and product ranges as well as to enhance its robustness against stressful conditions such as inhibitory compounds within the lignocellulosic hydrolysates and slurries. We also discuss a few metabolic engineering strategies that can be applied in Z. mobilis to further develop it as a robust workhorse for economic lignocellulosic bioproducts. In addition, we briefly review the progress of metabolic engineering in Z. mobilis related to the classical synthetic biology cycle of "Design-Build-Test-Learn", as well as the progress and potential to develop Z. mobilis as a model chassis for biorefinery practices in the synthetic biology era. Copyright © 2018 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  13. Ethanol production with a flocculating mutant of Zymomonas mobilis and immobilized glycoside hydrolases. Ethanolgewinnung mit einer flockenden Mutante von Zymomonas mobilis und immobilisierten Glycosidhydrolasen

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    Tramm-Werner, S.

    1987-05-25

    A method to extend the substrate spectrum of Z. mobilis was developed. Higher ethanol yields were achieved by simultaneous use of hydrolases cross-linked with glutar aldehyde together with the flocculating Zymomonas cells (TW 602). Apart from the high product yields, the method is characterized by low susceptibility to infections.

  14. Single zymomonas mobilis strain for xylose and arabinose fermentation

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    Zhang, Min; Chou, Yat-Chen; Picataggio, Stephen K.; Finkelstein, Mark

    1998-01-01

    This invention relates to single microorganisms which normally do not ferment pentose sugars which are genetically altered to ferment the pentose sugars, xylose and arabinose, to produce ethanol, and a fermentation process utilizing the same. Examples include Zymomonas mobilis which has been transformed with a combination of E. coli genes for xylose isomerase, xylulokinase, L-arabinose isomerase, L-ribulokinase, L-ribulose 5-phosphate 4-epimerase, transaldolase and transketolase. Expression of added genes are under the control of Z. mobilis promoters. These newly created microorganisms are useful for fermenting glucose, xylose and arabinose, produced by hydrolysis of hemicellulose and cellulose or starch, to produce ethanol.

  15. Synthesis of sorbitol by Zymomonas mobilis under high osmotic pressure Síntese de sorbitol por Zymomonas mobilis sob elevada pressão osmótica

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    Márcio de Barros

    2006-09-01

    Full Text Available The bacterium Zymomonas mobilis presents potential for sorbitol production when grown in culture medium with high sugar concentration. Sorbitol is produced and accumulated in the periplasma of the bacterium to protect the cells from the harmful effects of high osmotic pressure that results from the action of invertase on sucrose. The conversion of sucrose into glucose and fructose increases the osmolarity of the medium. However, an excessive increase in the osmotic pressure may decrease the sorbitol production. In this work Saccharomyces cerevisiae invertase was added two media containing sucrose 200 and 300 g.L-1. Sorbitol production in sucrose at 200 g.L-1 was 42.35 and 38.42 g.L-1, with and without the invertase treatment, respectively. In the culture medium with 300 g.L-1 sucrose, production reached 60.4 g.L-1 and with invertase treatment was 19.14 g.L-1. These results indicated that the excessive rise in osmotic pressure led to a significant decrease in sorbitol production by the Zymomonas mobilis bacterium in the sucrose medium treated with invertase.A bactéria Zymomonas mobilis, apresenta potencial para produção de sorbitol quando crescida em meio com alta concentração de açúcar. O sorbitol produzido é acumulado no periplasma da bactéria para conter os efeitos prejudiciais da elevada pressão osmótica, que resulta pela ação da enzima invertase, que promove hidrólise da sacarose. A conversão da sacarose em glicose e frutose aumentando a osmolaridade do meio. Entretanto, um aumento excessivo na pressão osmótica pode inibir a produção de sorbitol pela bactéria. Este trabalho empregou invertase de Saccharomyces cerevisiae nos meios de fermentação com sacarose a 200 e 300 g.L-1. A produção de sorbitol no meio com sacarose a 200 g.L-1 foi de 42,35 g.L-1 e 38,42 g.L-1 com e sem tratamento com invertase respectivamente. No meio com 300 g.L-1 sem tratamento, a produção foi de 60,42 e com tratamento 19,14 g.L-1. Estes

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

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    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.

  17. Inhibition of Xanthomonas citri subsp. citri, causal agent of citrus canker, by a strain of Zymomonas mobilis mobilis isolated from sugarcane

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    Romero, María E.; Ramallo, C. Jacqueline; Ploper, L. Daniel

    2008-01-01

    Zymomonas mobilis mobilis (Zm) produce factores antimicrobianos que actúan sobre un amplio espectro de microorganismos patógenos para el hombre, animales y plantas. Un problema importante a resolver en los tratamientos con antimicrobianos, es el desarrollo de resistencia a compuestos empleados actualmente, no siendo las bacterias fitopatógenas una excepción. En el presente trabajo se realizaron ensayos de antagonismo con células (pruebas de estrías cruzadas) y sobrenadantes concentrados (Sc) ...

  18. Optimization of asparaginase production from Zymomonas mobilis by continuous fermentation

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    Francieli Bortoluzzi Menegat

    2016-10-01

    Full Text Available Asparaginase is an enzyme used in clinical treatments as a chemotherapeutic agent and in food technology to prevent acrylamide formation in fried and baked foods. Asparaginase is industrially produced by microorganisms, mainly gram-negative bacteria. Zymomonas mobilis is a Gram-negative bacterium that utilizes glucose, fructose and sucrose as carbon source and has been known for its efficiency in producing ethanol, sorbitol, levan, gluconic acid and has recently aroused interest for asparaginase production. Current assay optimizes the production of Z. mobilis asparaginase by continuous fermentation using response surface experimental design and methodology. The studied variables comprised sucrose, yeast extract and asparagine. Optimized condition obtained 117.45 IU L-1 with dilution rate 0.20 h-1, yeast extract 0.5 g L-1, sucrose 20 g L-1 and asparagine 1.3 g L-1. Moreover, carbon:nitrogen ratio (1:0.025 strongly affected the response of asparaginase activity. The use of Z. mobilis by continuous fermentation has proved to be a promising alternative for the biotechnological production of asparaginase.

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

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    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

  20. Transcriptome profiling of Zymomonas mobilis under ethanol stress

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    He Ming-xiong

    2012-10-01

    Full Text Available Abstract Background High tolerance to ethanol is a desirable characteristics for ethanologenic strains used in industrial ethanol fermentation. A deeper understanding of the molecular mechanisms underlying ethanologenic strains tolerance of ethanol stress may guide the design of rational strategies to increase process performance in industrial alcoholic production. Many extensive studies have been performed in Saccharomyces cerevisiae and Escherichia coli. However, the physiological basis and genetic mechanisms involved in ethanol tolerance for Zymomonas mobilis are poorly understood on genomic level. To identify the genes required for tolerance to ethanol, microarray technology was used to investigate the transcriptome profiling of the ethanologenic Z. mobilis in response to ethanol stress. Results We successfully identified 127 genes which were differentially expressed in response to ethanol. Ethanol up- or down-regulated genes related to cell wall/membrane biogenesis, metabolism, and transcription. These genes were classified as being involved in a wide range of cellular processes including carbohydrate metabolism, cell wall/membrane biogenesis, respiratory chain, terpenoid biosynthesis, DNA replication, DNA recombination, DNA repair, transport, transcriptional regulation, some universal stress response, etc. Conclusion In this study, genome-wide transcriptional responses to ethanol were investigated for the first time in Z. mobilis using microarray analysis.Our results revealed that ethanol had effects on multiple aspects of cellular metabolism at the transcriptional level and that membrane might play important roles in response to ethanol. Although the molecular mechanism involved in tolerance and adaptation of ethanologenic strains to ethanol is still unclear, this research has provided insights into molecular response to ethanol in Z. mobilis. These data will also be helpful to construct more ethanol resistant strains for cellulosic

  1. Optimization of levan production by Zymomonas mobilis

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    V. K Ananthalakshmy

    1999-01-01

    Full Text Available Effect of different fermentation conditions on levan production by Zymomonas mobilis B-4286 was studied. Levan production increased from 5.7-g/l to 12.6-g/l with an increase in initial sucrose concentration (50-150 g/l. Above 15% (20 and 25% sucrose concentration, there was no increase in the biomass. The sucrose hydrolysis and levan production occurred even in the absence of significant growth of cells. Maximum amount of levan was produced (14.5 g/l at pH 5 and 15 g /l at 25(0C temperature. At temperature between 35(0C and 40(0C, levan production was not detected. Presence of glucose in the medium considerably reduced levan production (2.8 g/l than fructose 6.7g/l.O efeito de diferentes condições de fermentação na produção de levan por Zymomonas mobilis B-4286 foi estudado. A produção de Levan aumentou de 5.7-g/l a 12.6-g/l com o aumento da concentração inicial de sacarose (50-150 g/l. Acima de 15%, 20 e 25% a concentração de sacarose, não propiciou nenhum acréscimo na formação de biomassa. A hidrólise da sacarose e produção de Levan ocorreram de forma normal na ausência de um crescimento celular significativo. A concentração máxima de levan produzida foi (14.5 g/l em pH 5, 15 g /l a 25(0 C. Na temperatura entre 35(0C e 40(0 C, não ocorreu a produção de levan. A presença de glicose no meio de cultivo reduziu consideravelmente a produção média de levan (2.8 g/l bem como a de frutose (6.7g/l..

  2. Construction of an Unmarked Zymomonas mobilis Mutant Using a Site-Specific FLP Recombinase

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    Shao-Lan Zou

    2012-01-01

    Full Text Available Flippase expression was carried out in Zymomonas mobilis strain ZM4. The FRT-flanked selection marker gene was first integrated into the ZM4 chromosome by homologous recombination. The Saccharomyces cerevisiae flp gene was then introduced under the control of the ZM4 gap gene promoter (Pgap, encoding glyceraldehyde-3-phosphate dehydrogenase or the λ bacteriophage cI857-pR contained in the broad-host-range cloning vector pBBR1-MCS-2. This study demonstrated that flp was expressed and that the deletion frequency of the FRT-flanked marker gene was very high (approx. 100 %. In addition, the flp gene expression vector could be conveniently removed from the resulting unmarked Z. mobilis mutants by serially transferring the cells three times into antibiotic-free medium, thereby establishing an efficient method for constructing unmarked Z. mobilis mutants.

  3. Aktivitas Zymomonas mobilis pada produk etanol dari buah semu jambu mete (Anacardium occidentale dengan variasi sumber nitrogen

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    AKHMAD MUSTOFA

    2010-05-01

    Full Text Available Mustofa A, Suranto. 2010. Aktivitas Zymomonas mobilis pada produk etanol daribuah semu jambu mete (Anacardium occidentale dengan variasi sumber nitrogen. Bioteknologi 7: 1-9. Penelitian ini bertujuan mengetahui kemampuan Zymomonas mobilis dalam memproduksi etanol melalui proses fermentasi batch (selama 24, 48 dan 72 jam, menggunakan sumber karbon sari buah jambu mete (varietas merah, hijau dan kuning dan sumber nitrogen berupa urea, ammonium sulfat, ekstrak kecambah kacang hijau dan ekstrak kacang koro (Mucuna pruriens. Hasil penelitian menunjukkan bahwa varietas buah jambu mete hijau dengan sumber nitrogen ammonium sulfat dan lama fermentasi 24 jam memberikan hasil etanol yang paling optimal. Pada perlakuan tersebut diperoleh nilai pH 5,87, kadar gula reduksi 7,64 g/100 mL (tingkat konsumsi 48,44%, jumlah bakteri 8,0x107 (µ = 0,154 dan etanol sebesar 33,02 g/L (Ye = 90,19%.

  4. Modeling of Zymomonas mobilis central metabolism for novel metabolic engineering strategies.

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    Kalnenieks, Uldis; Pentjuss, Agris; Rutkis, Reinis; Stalidzans, Egils; Fell, David A

    2014-01-01

    Mathematical modeling of metabolism is essential for rational metabolic engineering. The present work focuses on several types of modeling approach to quantitative understanding of central metabolic network and energetics in the bioethanol-producing bacterium Zymomonas mobilis. Combined use of Flux Balance, Elementary Flux Mode, and thermodynamic analysis of its central metabolism, together with dynamic modeling of the core catabolic pathways, can help to design novel substrate and product pathways by systematically analyzing the solution space for metabolic engineering, and yields insights into the function of metabolic network, hardly achievable without applying modeling tools.

  5. Mechanism of ethanol inhibition of fermentation in Zymomonas mobilis CP4

    International Nuclear Information System (INIS)

    Osman, Y.A.; Ingram, L.O.

    1985-01-01

    Accumulation of alcohol during fermentation is accompanied by a progressive decrease in the rate of sugar conversion to ethanol. In this study, the authors provided evidence that inhibition of fermentation by ethanol can be attributed to an indirect effect of ethanol on the enzymes of glycolysis involving the plasma membrane. Ethanol decreased the effectiveness of the plasma membrane as a semipermeable barrier, allowing leakage of essential cofactors and coenzymes. This leakage of cofactors and coenzymes, coupled with possible additional leakage of intermediary metabolites en route to ethanol formation, is sufficient to explain the inhibitory effects of ethanol on fermentation in Zymomonas mobilis

  6. Continuous ethanol production from sugar beet molasses using an osmotolerant mutant strain of zymomonas mobilis

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    Park, S.C.; Baratti, J.C. (Univ. de Provence, Marseille (France). Centre National de la Recherche Scientifique)

    1992-01-25

    In conventional alcohol fermentation processes using yeast species, the substrate cost represents a major fraction of the total production cost. Therefore, it may be very attractive to use the bacterium Zymomonas mobilis, since it has shown higher ethanol yields than yeasts when grown on a glucose-based medium. A report is made on the use of mutant strain of Zymomonas mobilis for ethanol production from hydrolyzed sugar beet molasses in a two-stage continuous culture which showed high ethanol yield and an ethanol concentration sufficiently high for economical recovery. A single stage continuous culture was first operated in an attempt to reduce the formation of sorbitol. Further on, a second fermentor was added with additional substrate feeding to increase the effluent ethanol concentration. An ethanol concentration of 59.9g/l was obtained at 97% sugar conversion and at high ethanol yield. The volumetric ethanol productivity was superior to that of batch fermentation but inferior to that of a single-stage continuous system with the same medium. However, the ethanol concentration was increased to a level acceptable for economical recovery. 18 refs., 3 figs., 5 tabs.

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

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    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.

  8. Bioethanol Production from Iles-Iles (Amorphopallus campanulatus Flour by Fermentation using Zymomonas mobilis

    Directory of Open Access Journals (Sweden)

    Kusmiyati Kusmiyati

    2016-02-01

    Full Text Available Due to the depletion of fossil oil sources, Indonesia attempts to search new source of bioenergy including bioethanol. One of this sources is Iles-iles tubers (Amorphophallus campanulatus, which is abundantly available in Java Indonesia. The carbohydrate content in Iles-Iles tuber flour was 77% and it can be converted to ethanol by three consecutive steps methods consist of liquefaction-saccharification using α and β-amylase, respectively and then followed by fermentation by using Z. mobilis. The objective of this research was to convert the Iles-iles flour to bioethanol by fermentation process with Z.mobilis. The ethanol production process was studied at various starch concentration 15-30% g/L, Z. mobilis concentration (10-40% and pH fermentation of (4-6. The result showed that the yield of bioethanol (10.33% was the highest at 25% starch concentration and 25% of Z.mobilis concentration. The optimum conditions was found at 4.5, 30°C, 10%, 120 h for pH, temperature, Z. mobilis concentration and fermentation time, respectively  at which  ACT tuber flour produced a maximum ethanol of 10.33 % v/v.Article History: Received November 12nd 2015; Received in revised form January 25th 2016; Accepted January 29th 2016; Available online How to Cite This Article: Kusmiyati , Hadiyanto,H  and Kusumadewi, I (2016. Bioethanol Production from Iles-Iles (Amorphopallus campanulatus Flour by Fermentation using Zymomonas mobilis. Int. Journal of Renewable Energy Development, 9(1, 9-14 http://dx.doi.org/10.14710/ijred.5.1.9-14 

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

    Science.gov (United States)

    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...

  10. Ethanol production from molasses by immobilized cells of zymomonas mobilis EMCC 1546

    International Nuclear Information System (INIS)

    Meliegy, S.A.; Abdelaziz, A.H.

    2004-01-01

    Ethanol production from beet molasses by zymomonas mobilis EMCC 1546 was studied using continuous processes in which immobilized bacterial cells of Z.mobilis EMCC 1546 was grown on both sodium alginate and polyvinyl alcohol(PVA). The fermentation was performed in a shaking incubation and 1-liter ferment or with final working 750 ml. The initial sugar concentration studied was 50, 100,150, 200 and 250 g/l. The results showed that optimum initial sugar for ethanol production was 200 g/l. In batch fermentation, the highest ethanol concentration was 28.50 g/. Also effect of gamma irradiation was studied to enhance ethanol production. The highest ethanol production at dose dose 0.25 kGy was 34.82 g/l. The results showed that continuous fermentation, at dilution rate 1.36 (I/h), helped to increase the ethanol production significantly and continuous fermentation with immobilized cells in alginate gave higher ethanol production, 35.8 (g/I), as compared with those immobilized in hydrogel (PVA)

  11. Ethanol Production from Kitchen Garbage Using Zymomonas mobilis: Optimization of Parameters through Statistical Experimental Designs

    OpenAIRE

    Ma, H.; Wang, Q.; Gong, L.; Wang, X.; Yin, W.

    2008-01-01

    Plackett-Burman design was employed to screen 8 parameters for ethanol production from kitchen garbage by Zymomonas mobilis in simultaneous saccharification and fermentation. The parameters were divided into two parts, four kinds of enzymes and supplementation nutrients. The result indicated that the nutrient inside kitchen garbage could meet the requirement of ethanol production without supplementation, only protease and glucoamylase were needed to accelerate the ethanol production. The opti...

  12. Quantifying the metabolic capabilities of engineered Zymomonas mobilis using linear programming analysis

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    Tsantili Ivi C

    2007-03-01

    Full Text Available Abstract Background The need for discovery of alternative, renewable, environmentally friendly energy sources and the development of cost-efficient, "clean" methods for their conversion into higher fuels becomes imperative. Ethanol, whose significance as fuel has dramatically increased in the last decade, can be produced from hexoses and pentoses through microbial fermentation. Importantly, plant biomass, if appropriately and effectively decomposed, is a potential inexpensive and highly renewable source of the hexose and pentose mixture. Recently, the engineered (to also catabolize pentoses anaerobic bacterium Zymomonas mobilis has been widely discussed among the most promising microorganisms for the microbial production of ethanol fuel. However, Z. mobilis genome having been fully sequenced in 2005, there is still a small number of published studies of its in vivo physiology and limited use of the metabolic engineering experimental and computational toolboxes to understand its metabolic pathway interconnectivity and regulation towards the optimization of its hexose and pentose fermentation into ethanol. Results In this paper, we reconstructed the metabolic network of the engineered Z. mobilis to a level that it could be modelled using the metabolic engineering methodologies. We then used linear programming (LP analysis and identified the Z. mobilis metabolic boundaries with respect to various biological objectives, these boundaries being determined only by Z. mobilis network's stoichiometric connectivity. This study revealed the essential for bacterial growth reactions and elucidated the association between the metabolic pathways, especially regarding main product and byproduct formation. More specifically, the study indicated that ethanol and biomass production depend directly on anaerobic respiration stoichiometry and activity. Thus, enhanced understanding and improved means for analyzing anaerobic respiration and redox potential in vivo are

  13. Comparative study of bio-ethanol production from mahula (Madhuca latifolia L.) flowers by Saccharomyces cerevisiae and Zymomonas mobilis

    Energy Technology Data Exchange (ETDEWEB)

    Behera, Shuvashish; Mohanty, Rama Chandra [Department of Botany, Utkal University, Vanivihar, Bhubaneswar 751004, Orissa (India); Ray, Ramesh Chandra [Microbiology Laboratory, Central Tuber Crops Research Institute (Regional Centre), Bhubaneswar 751019, Orissa (India)

    2010-07-15

    Mahula (Madhuca latifolia L.) flower is a suitable alternative cheaper carbohydrate source for production of bio-ethanol. Recent production of bio-ethanol by microbial fermentation as an alternative energy source has renewed research interest because of the increase in the fuel price. Saccharomyces cerevisiae (yeast) and Zymomonas mobilis (bacteria) are two most widely used microorganisms for ethanol production. In this study, experiments were carried out to compare the potential of the yeast S. cerevisiae (CTCRI strain) with the bacterium Z. mobilis (MTCC 92) for ethanol fermentation from mahula flowers. The ethanol production after 96 h fermentation was 149 and 122.9 g kg{sup -1} flowers using free cells of S. cerevisiae and Z. mobilis, respectively. The S. cerevisiae strain showed 21.2% more final ethanol production in comparison to Z. mobilis. Ethanol yield (Yx/s), volumetric product productivity (Qp), sugar to ethanol conversion rate (%) and microbial biomass concentration (X) obtained by S. cerevisiae were found to be 5.2%, 21.1%, 5.27% and 134% higher than Z. mobilis, respectively after 96 h of fermentation. (author)

  14. Comparative study of bio-ethanol production from mahula (Madhuca latifolia L.) flowers by Saccharomyces cerevisiae and Zymomonas mobilis

    International Nuclear Information System (INIS)

    Behera, Shuvashish; Mohanty, Rama Chandra; Ray, Ramesh Chandra

    2010-01-01

    Mahula (Madhuca latifolia L.) flower is a suitable alternative cheaper carbohydrate source for production of bio-ethanol. Recent production of bio-ethanol by microbial fermentation as an alternative energy source has renewed research interest because of the increase in the fuel price. Saccharomyces cerevisiae (yeast) and Zymomonas mobilis (bacteria) are two most widely used microorganisms for ethanol production. In this study, experiments were carried out to compare the potential of the yeast S. cerevisiae (CTCRI strain) with the bacterium Z. mobilis (MTCC 92) for ethanol fermentation from mahula flowers. The ethanol production after 96 h fermentation was 149 and 122.9 g kg -1 flowers using free cells of S. cerevisiae and Z. mobilis, respectively. The S. cerevisiae strain showed 21.2% more final ethanol production in comparison to Z. mobilis. Ethanol yield (Yx/s), volumetric product productivity (Qp), sugar to ethanol conversion rate (%) and microbial biomass concentration (X) obtained by S. cerevisiae were found to be 5.2%, 21.1%, 5.27% and 134% higher than Z. mobilis, respectively after 96 h of fermentation. (author)

  15. Recombinant L-Asparaginase from Zymomonas mobilis: A Potential New Antileukemic Agent Produced in Escherichia coli.

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    Karen Einsfeldt

    Full Text Available L-asparaginase is an enzyme used as a chemotherapeutic agent, mainly for treating acute lymphoblastic leukemia. In this study, the gene of L-asparaginase from Zymomonas mobilis was cloned in pET vectors, fused to a histidine tag, and had its codons optimized. The L-asparaginase was expressed extracellularly and intracellularly (cytoplasmically in Escherichia coli in far larger quantities than obtained from the microorganism of origin, and sufficient for initial cytotoxicity tests on leukemic cells. The in silico analysis of the protein from Z. mobilis indicated the presence of a signal peptide in the sequence, as well as high identity to other sequences of L-asparaginases with antileukemic activity. The protein was expressed in a bioreactor with a complex culture medium, yielding 0.13 IU/mL extracellular L-asparaginase and 3.6 IU/mL intracellular L-asparaginase after 4 h of induction with IPTG. The cytotoxicity results suggest that recombinant L-asparaginase from Z. mobilis expressed extracellularly in E.coli has a cytotoxic and cytostatic effect on leukemic cells.

  16. Effect of initial pH in levan production by Zymomonas mobilis immobilized in sodium alginate

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    Vidiany Aparecida Queiroz Santos

    2014-04-01

    Full Text Available Zymomonas mobilis was immobilized using a cell suspension fixed to 8.6 x 107 CFU mL-1 by spectrophotometry. This biomass was suspended in sodium alginate solution (3% that was dropped with a hypodermic syringe into 0.2 M calcium chloride solution. Was test two initial pH of fermentation medium (4 and 5 and different sucrose concentrations 15, 20, 25, 30 and 35% at 30˚C, without stirring for 24, 48, 72 and 96 hours. The levan production to pH 4 was high in sucrose 25% for 24 (16.51 g L-1 and 48 (15.31 g L-1 hours. The best values obtained to pH 5 was in sucrose 35% during 48 (22.39 g L-1 and 96 (23.5 g L-1 hours, respectively. The maximum levan yield was 40.8% and 22.47% in sucrose 15% to pH 4 and 5, respectively. Substrate consumption to pH 4 was bigger in sucrose 15 (56.4% and 20% (59.4% and to pH 5 was in 25 (68.85% and 35% (64.64%. In relation to immobilization efficiency, Zymomonas mobilis showed high adhesion and colonization in support, indicated by cell growth increased from 107 to 109 CFU mL-1 during fermentation time.

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

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    Lu Tse-Yuan S

    2010-05-01

    Full Text Available Abstract Background 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. Results We generated a Z. mobilis hfq insertion mutant AcRIM0347 in an acetate tolerant strain (AcR background and investigated its role in model lignocellulosic pretreatment inhibitors including acetate, vanillin, furfural and hydroxymethylfurfural (HMF. Saccharomyces cerevisiae Lsm protein (Hfq homologue mutants and Lsm protein overexpression strains were also assayed for their inhibitor phenotypes. Our results indicated that all the pretreatment inhibitors tested in this study had a detrimental effect on both Z. mobilis and S. cerevisiae, and vanillin had the most inhibitory effect followed by furfural and then HMF for both Z. mobilis and S. cerevisiae. AcRIM0347 was more sensitive than the parental strain to the inhibitors and had an increased lag phase duration and/or slower growth depending upon the conditions. The hfq mutation in AcRIM0347 was complemented partially by trans-acting hfq gene expression. We also assayed growth phenotypes for S. cerevisiae Lsm protein mutant and overexpression phenotypes. Lsm1, 6, and 7 mutants showed reduced tolerance to acetate and other pretreatment inhibitors. S. cerevisiae Lsm protein overexpression strains showed increased acetate and HMF resistance as compared to the wild-type, while the overexpression strains showed greater inhibition under vanillin stress conditions. Conclusions We have shown the utility of the pKNOCK suicide plasmid for

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

    Science.gov (United States)

    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.

  19. Fermentasi Etanol Sari Buah Semu Jambu Mete (Anacardium occidentale L. oleh Zymomonas mobilis dengan Penambahan Urea

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    RATNA SETYANINGSIH

    2006-11-01

    Full Text Available Cashew present in abundant amount in Indonesia but they had not muchbeen exploited. This research was to study ethanol fermentation from cashew juice by Zymomonas mobilis using urea as nitrogen source. The aims of this research was to know the best urea concentration and optimum fermentation duration to produce the highest content of ethanol in ethanol fermentation from cashew juice by Z. mobilis. The urea concentration in media was prepared 0%; 0.2% and 0.4%. The media cashew juice + urea (100 mL was inoculated with 1 mL Z. mobilis 2x108 cell/mL. Initial pH, reducing sugar, amount of microorganism and concentration of ethanol was calculated everyday during 3 days. It could be concluded that 0.2% of urea produced the highest content of ethanol that was an amount 40.51%, followed by urea 0% was 30.59% and urea 0.4% was 25.63%. The optimum fermentation duration to produce the highest content of ethanol was 2 days.

  20. Production of ethanol by Saccharomyces cerevisiae and Zymomonas mobilis Coimmobilized: proposal for the use of organic waste

    OpenAIRE

    Ruiz-Marín, Alejandro; Canedo-López, Yunuén; Narváez-García, Asteria; Robles-Heredia, J. Carlos

    2016-01-01

    Abstract: Fermentation technologies were developed to improve the production of ethanol and an alternative is the immobilization technology, which offers advantages in comparison with free cells culture, such as the possibility of efficiently incorporating symbiotic bacteria in the same matrix. The aim of this study was to evaluate, in equivalent medium, the use of mango (Mangifera indica) waste to produce ethanol. The study compared the production of ethanol by using Zymomonas mobilis and Sa...

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

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1989-08-01

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

  3. A kinetic model and simulation of starch saccharification and simultaneous ethanol fermentation by amyloglucosidase and Zymomonas mobilis

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C G [Michigan Univ., Ann Arbor, MI (United States). Dept. of Chemical Engineering; Kim, C H; Rhee, S K [Korea Inst. of Science and Technology, Taejon (Korea, Republic of). Genetic Engineering Research Inst.

    1992-07-01

    A mathematical model is described for the simultaneous saccharification and ethanol fermentation (SSF) of sago starch using amyloglycosidase (AMG) and Zymomonas mobilis. By introducing the degree of polymerization (DP) of oligosaccharides produced from sago starch treated with {alpha}-amylase, a series of Michaelis-Menten equations was obtained. After determining kinetic parameters from the results of simple experiments and from the subsite mapping theory, this model was adapted to simulate the SSF process. The results of simulation for SSF are in good agreement with experimental results. (orig.).

  4. STATE ESTIMATION IN ALCOHOLIC CONTINUOUS FERMENTATION OF ZYMOMONAS MOBILIS USING RECURSIVE BAYESIAN FILTERING: A SIMULATION APPROACH

    Directory of Open Access Journals (Sweden)

    Olga Lucia Quintero

    2008-05-01

    Full Text Available This work presents a state estimator for a continuous bioprocess. To this aim, the Non Linear Filtering theory based on the recursive application of Bayes rule and Monte Carlo techniques is used. Recursive Bayesian Filters Sampling Importance Resampling (SIR is employed, including different kinds of resampling. Generally, bio-processes have strong non-linear and non-Gaussian characteristics, and this tool becomes attractive. The estimator behavior and performance are illustrated with the continuous process of alcoholic fermentation of Zymomonas mobilis. Not too many applications with this tool have been reported in the biotechnological area.

  5. The Low Energy-Coupling Respiration in Zymomonas mobilis Accelerates Flux in the Entner-Doudoroff Pathway.

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    Reinis Rutkis

    Full Text Available Performing oxidative phosphorylation is the primary role of respiratory chain both in bacteria and eukaryotes. Yet, the branched respiratory chains of prokaryotes contain alternative, low energy-coupling electron pathways, which serve for functions other than oxidative ATP generation (like those of respiratory protection, adaptation to low-oxygen media, redox balancing, etc., some of which are still poorly understood. We here demonstrate that withdrawal of reducing equivalents by the energetically uncoupled respiratory chain of the bacterium Zymomonas mobilis accelerates its fermentative catabolism, increasing the glucose consumption rate. This is in contrast to what has been observed in other respiring bacteria and yeast. This effect takes place after air is introduced to glucose-consuming anaerobic cell suspension, and can be simulated using a kinetic model of the Entner-Doudoroff pathway in combination with a simple net reaction of NADH oxidation that does not involve oxidative phosphorylation. Although aeration hampers batch growth of respiring Z. mobilis culture due to accumulation of toxic byproducts, nevertheless under non-growing conditions respiration is shown to confer an adaptive advantage for the wild type over the non-respiring Ndh knock-out mutant. If cells get occasional access to limited amount of glucose for short periods of time, the elevated glucose uptake rate selectively improves survival of the respiring Z. mobilis phenotype.

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

    Science.gov (United States)

    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.

  7. Evaluation of wheat stillage for ethanol production by recombinant Zymomonas mobilis

    Energy Technology Data Exchange (ETDEWEB)

    Davis, L.; Peiris, P. [University of Western Sydney, Penrith (Australia). School of Science, Food and Horticulture; Young-Jae Jeon; Svenson, C.; Rogers, P. [University of New South Wales, Sydney (Australia). School of Biotechnology and Biomolecular Sciences; Pearce, J. [Manildra Group, Bomaderry (Australia)

    2005-07-01

    Stillage is the main residue from the starch-to-ethanol fermentation process.Carbohydrates (hemicellulose and cellulose) comprise approximately 50% (w/w)of the total components of stillage. Conversion of the hemicellulose and cellulose to fermentable sugars and then to ethanol has the potential to significantly increase the efficiency of the process. The hydrolysis of stillage to fermentable sugars was optimised using 2% (v/v) H{sub 2}SO{sub 4} at 100{sup o}C for 5.5 h and produced 18 g/L xylose, 11.5 g/L arabinose and 6.5 g/L glucose from 120 g/L stillage. Further hydrolysis using enzymes increased the release of glucose by 61%. Furfural, acetate and lactate were the main inhibitors present in the acid hydrolysate of stillage. The lignin-derived inhibitors hydroxymethylfuraldehyde, hydroxybenzaldehyde, vanillin and syringaldehyde were not detected. Neutralisation of the hydrolysate with lime to pH 5 decreased the concentration of furfural by 50%. Fermentation of hydrolysate supplemented with glucose 10 g/L, by recombinant Zymomonas mobilis ZM4(pZB5), produced 11 g/L of ethanol after 70 h, with residual xylose 12 g/L. Supplementation of the hydrolysate with 5 g/L yeast extract and 40 g/L glucose produced 28 g/L ethanol with 2.6 g/L residual xylose after 18 h. Arabinose was not utilised by this particular recombinant strain. From the results, Z. mobilis ZM4(pZB5) may be a suitable candidate for the fermentation of both glucose and xylose in stillage acid hydrolysates. (author)

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

    Science.gov (United States)

    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.

  9. Optimization of ethanol production by Zymomonas mobilis in sugar cane molasses fermentation

    Directory of Open Access Journals (Sweden)

    Marcos Roberto Oliveira

    2005-02-01

    Full Text Available The present study aimed at the optimization of the ethanol production by Zymomonas mobilis CP4, during the fermentation of sugar cane molasses. As for the optimization process, the response surface methodology was applied, using a 33 incomplete factorial design, being the independent variables: total reducing sugar (TRS concentration in the molasses from 10, 55 and 100 g/L (x1; yeast extract concentration from 2, 11 and 20 g/L (x2, and fermentation time from 6, 15 and 24 hours (x3. The dependant variables or answers were the production and productivity of ethanol. By the analysis of the results, a good adjustment of the model to the experimental data was obtained. In the levels studied, the best condition for the production of ethanol was with 100 g/L TRS in the syrup, 2.0 g/L of yeast extract and the fermentation time between 20 and 24 hours, producing 30 g/L of ethanol.

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

    Science.gov (United States)

    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.

  11. Modelling of the metabolism of Zymomonas mobilis

    Energy Technology Data Exchange (ETDEWEB)

    Posten, C; Thoma, M

    1986-01-01

    In order to optimize fermentations with respect to media, reactor configuration, and control a structured model of the metabolism of Zymononas mobilis has been developed. The model is based on structure of metabolism, rate limiting steps, energy balance and metabolic elemental balances. A three-fold effect of ethanol has been observed concerning substrate-turnover, ammonia uptake and energy consumption. In addition to the metabolic view a structured cell-membrane-model should be considered.

  12. Utilization of raw materials from agroindustry – sugar cane juice and yeast extract – for asparaginase production by Zymomonas mobilis CP4/ Uso de matérias primas da agroindústria – garapa e extrato de levedura – na produção de asparaginase por Zymomonas mobilis CP4

    Directory of Open Access Journals (Sweden)

    Maria Antonia Pedrine Colabone Celligoi

    2007-08-01

    Full Text Available Sugar cane juice and yeast extract have been used for asparaginase production by Z. mobilis CP4. A complete factorial design of two variables (yeast extract and asparagin at three levels (1.0; 5.5 and 10.0 g/L with one replication at the central point was used. Batch fermentation utilised sugar cane juice diluted at 8 % (W/V of Total Sugars and an inoculum of 2 mg of cells/mL. After fermentation time of 18 hours, the highest production of asparaginase was 9.75 U/L using both yeast extract (5.5 g/L and asparagin (1.0 g/l.Garapa e extrato de levedura foram usados na produção de asparaginase por Zymomonas mobilis CP4. Na otimização utilizou metodologia de superfície de resposta com 2 variáveis (extrato de levedura e asparagina em 3 níveis (1,0; 5,5 e 10,0 g/L e uma repetição do ponto central. A fermentação em batelada utilizou garapa diluída a 8 % (P/V de Açúcares Totais e inóculo de Zymomonas mobilis CP4 na concentração de 2 mg/mL. Após a fermentação de 18 horas, a maior produção obtida de asparaginase foi de 9,75 U/L em extrato de levedura em 5,5 g/L e asparagina em 1,0 g/L.

  13. Acción inhibitoria de una cepa de Zymomonas mobilis mobilis aislada de caña de azúcar sobre Xanthomonas citri subsp. citri, agente causal de la cancrosis de los cítricos Inhibition of Xanthomonas citri subsp. citri, causal agent of citrus canker, by a strain of Zymomonas mobilis mobilis isolated from sugarcane

    Directory of Open Access Journals (Sweden)

    María E. Romero

    2008-06-01

    Full Text Available Zymomonas mobilis mobilis (Zm produce factores antimicrobianos que actúan sobre un amplio espectro de microorganismos patógenos para el hombre, animales y plantas. Un problema importante a resolver en los tratamientos con antimicrobianos, es el desarrollo de resistencia a compuestos empleados actualmente, no siendo las bacterias fitopatógenas una excepción. En el presente trabajo se realizaron ensayos de antagonismo con células (pruebas de estrías cruzadas y sobrenadantes concentrados (Sc (por difusión en agar preparados a partir de cultivos de Zm (aislada de jugo de caña de azúcar producido en Tucumán, frente a la bacteria causal de la cancrosis: Xanthomonas citri subsp. citri. Se evaluaron aislamientos de Xcc sensibles (Xc y resistentes (Xcr a compuestos a base de cobre. Los resultados obtenidos mostraron que la bacteria testigo fue inhibida totalmente por las células de Zm, ejerciendo un efecto bactericida. En los ensayos de difusión en el agar se observó que tanto Xc, como Xcr fueron sensibles al Sc de Zm. Se sabe, por estudios anteriores, que los metabolitos de Zymomonas tienen un efecto deletéreo en la membrana celular de E. coli AB1133, inhibiéndose la respiración de la bacteria inmediatamente de agregado Sc (60 UA. En el presente trabajo se observó el mismo efecto, inhibición total de la respiración en Xc, luego del agregado del Sc (60 UA. Por lo observado, se deduce que el blanco de acción de los metabolitos antimicrobianos de Sc en Xc, sería el mismo que el de E. coli AB1133. Con los resultados obtenidos se considera de interés encarar el estudio de los compuestos de Zm para ser empleados en el control de enfermedades que afectan los cultivos de valor económico de la región, como es el caso de la cancrosis, como así también profundizar acerca de la acción de dichos metabolitos en la membrana de Xanthomonas citri subsp. citri.Zymomonas mobilis mobilis (Zm produces antimicrobial factors, which have an effect on

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

    Science.gov (United States)

    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.

  15. Ethanol fermentation by immobilized cells of Zymomonas mobilis

    Energy Technology Data Exchange (ETDEWEB)

    Grote, W.

    1985-01-01

    Previous studies have shown that immobilized yeast cell cultures have commercial potential for fuel ethanol production. In this study the suitability of strains of Z. mobilis for whole cell immobilization was investigated. Experiments revealed that immobilization in Ca-alginate or K-carrageenan gel or use of flocculating strains was effective for ethanol production at relatively high productivities. Two laboratory size reactors were designed and constructed. These were a compartmented multiple discshaft column and a tower fermentor. Results of this work supported other studies that established that growth and fermentation could be uncoupled. The data indicated that specific metabolic rates were dependent on the nature of the fermentation media. The addition of lactobacilli to Z. mobilis continuous fermentations had only a transient effect, and was unlikely to affect an immobilized Z. mobilis process. With 150 gl/sup -1/ glucose media and a Z. mobilis ZM4 immobilized cell reactor, a maximum volumetric ethanol productivity of 55 gl/sup -1/h/sup -1/ was obtained. The fermentation of sucrose media or sucrose-based raw materials (molasses, cane juice, synthetic mill liquor) by immobilized Z. mobilis ZM4 revealed a pattern of rapid sucrose hydrolysis, preferential glucose utilization and the conversion of fructose to the undesirable by-products levan and sorbitol.

  16. The relationship between sucrose hydrolysis, sorbitol formation and mineral ion concentration during bioethanol formation using Zymomonas mobilis 2716

    Energy Technology Data Exchange (ETDEWEB)

    Doelle, M.B.; Doelle, H.W. (Queensland Univ., St. Lucia (Australia). Dept. of Microbiology); Greenfield, P.F. (Queensland Univ., St. Lucia (Australia). Dept. of Chemical Engineering)

    1990-11-01

    Investigations into the relationship between sucrose hydrolysis, sorbitol formation and mineral ion concentration during bioethanol formation by Zymomonas mobilis 2716 revealed two distinct phenomena responsible for carbon flow diversion, a 'sucrose effect' and a 'salt effect'. Neither of the two phenomena affects sucrose hydrolysis, but they divert carbon flow of the fructose monomer leading to its own accumulation, sorbitol or oligosaccharide formation. Sucrose concentrations in excess of 15% (w/v) led to sorbitol formation, the level of which may exceed 2% (w/v) depending upon glucose accumulation during sucrose hydrolysis. Increasing mineral ion concentrations led initially to carbon losses and finally to fructose accumulation instead of sorbitol formation. This carbon loss can be corrected by the addition of invertase, which in turn leads to an increase in sorbitol, fructose and ethanol. Potassium and chloride are the dominant ions responsible for suppression of sorbitol formation and fructose uptake, encouraging oligosaccharide formation. These fructooligosaccharides must be of a type which can be converted to fructose, sorbitol and ethanol through the action of invertase. The requirement of invertase addition to prevent fructooligosaccharide formation is indirect evidence that Z. mobilis 2716 does not produce invertase. (orig.).

  17. Transcriptomic and metabolomic profiling of Zymomonas mobilis during aerobic and anaerobic fermentations

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    Palumbo Anthony V

    2009-01-01

    Full Text Available Abstract Background Zymomonas mobilis ZM4 (ZM4 produces near theoretical yields of ethanol with high specific productivity and recombinant strains are able to ferment both C-5 and C-6 sugars. Z. mobilis performs best under anaerobic conditions, but is an aerotolerant organism. However, the genetic and physiological basis of ZM4's response to various stresses is understood poorly. Results In this study, transcriptomic and metabolomic profiles for ZM4 aerobic and anaerobic fermentations were elucidated by microarray analysis and by high-performance liquid chromatography (HPLC, gas chromatography (GC and gas chromatography-mass spectrometry (GC-MS analyses. In the absence of oxygen, ZM4 consumed glucose more rapidly, had a higher growth rate, and ethanol was the major end-product. Greater amounts of other end-products such as acetate, lactate, and acetoin were detected under aerobic conditions and at 26 h there was only 1.7% of the amount of ethanol present aerobically as there was anaerobically. In the early exponential growth phase, significant differences in gene expression were not observed between aerobic and anaerobic conditions via microarray analysis. HPLC and GC analyses revealed minor differences in extracellular metabolite profiles at the corresponding early exponential phase time point. Differences in extracellular metabolite profiles between conditions became greater as the fermentations progressed. GC-MS analysis of stationary phase intracellular metabolites indicated that ZM4 contained lower levels of amino acids such as alanine, valine and lysine, and other metabolites like lactate, ribitol, and 4-hydroxybutanoate under anaerobic conditions relative to aerobic conditions. Stationary phase microarray analysis revealed that 166 genes were significantly differentially expressed by more than two-fold. Transcripts for Entner-Doudoroff (ED pathway genes (glk, zwf, pgl, pgk, and eno and gene pdc, encoding a key enzyme leading to ethanol

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

    Science.gov (United States)

    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.

  19. Evaluation of ethanol production from pito mash using Zymomonas ...

    African Journals Online (AJOL)

    PROMOTING ACCESS TO AFRICAN RESEARCH ... dinitrosalicylic acid (DNS) method, while analysis of ethanol content was performed using gas chromatography. ... Keywords: Pito mash, agro-industrial wastes, Zymomonas mobilis, ethanol, reducing sugars. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  20. Three new shuttle vectors for heterologous expression in Zymomonas mobilis

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    Qinghua Cao

    2016-01-01

    Conclusions: These results indicated that these expression vectors are useful tools for gene expression in Z. mobilis and this could provide a solid foundation for further studies of heterologous gene expression in Z. mobilis.

  1. Stillage as a Source of Growth Promoting Biofactors and a Stimulator of Levan and Extracellular Levansucrase Synthesis for Zymomonas mobilis

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    Mara Grube

    2002-01-01

    Full Text Available In the present work, the fermentation of simultaneous production of ethanol and levan by Zymomonas mobilis grown on different growth media has been studied. Yeast extract, rye stillage or sugar beet molasses stillage were used as additives to the basic sucrose media and the chemical composition, including vitamins, of the cultivation liquids have been determined. It has been shown that 0.5 % of yeast extract dry weight additive could be substituted by 10.0 % of native stillage additive. It was established that molasses stillage stimulates the ethanol synthesis, but rye stillage additive is more preferable for levan production. The extracellular levansucrase obtained from the culture liquid resulted in similar fructooligosaccharide-producing activities using all the above-mentioned media additives.

  2. Evaluation of supplementation of sucrose medium on the synthesis of Zymomonas mobilis bio-products = Avaliação da suplementação do meio de sacarose na formação de bio– produtos por Zymomonas mobilis

    Directory of Open Access Journals (Sweden)

    Raquel Renan Jorge Borsari

    2010-07-01

    Full Text Available The effect of the variables pantothenic acid, yeast extract and sodiumchloride, as well as the cell permeabilization technique, were investigated on the formation of levan, ethanol, sorbitol and biomass of Zymomonas mobilis, using a 24-1 fraction factorial design. Cell growth was determined by turbidimetry at 605 nm, relating it to a biomass with a dry weight calibration curve. Reducing sugars were quantified according to Somogyi and Nelson. Total sugars were quantified by the phenol-sulfuric acid method, sorbitol by HPLC and ethanol. The levan produced was precipitated by the addition of absolute ethanol and quantified in fructose units. In levan biosynthesis, the variable that had the largest contribution was cell condition. The results suggested that the factors that most affected biomass and ethanol formation were sodium chloride concentration and cell condition that affected negatively on production. For sorbitol, the variable that had a significant effect was permeabilization, which decreased its synthesis. Studies to amplify the range of established factors would be important.A influência das variáveis: ácido pantotênico, extrato de levedura, cloreto de sódio, e a técnica de permeabilização celular foram investigadas na formação de levana, sorbitol, etanol e biomassa de Zymomonas mobilis utilizando um delineamento estatístico fatorial fracionado 24-1. A biomassa foi determinada por turbidimetria, Os açúcares redutores foram quantificados por Somogy e Nelson, açúcartotal por Fenol Sulfúrico, sorbitol por HPLC e etanol por micro-destilação. A levana produzida foi precipitada com etanol absoluto e determinada como unidade de frutose. Na biossíntese de levana, a variável que mais contribuiu foi a condição celular. Os resultadossugerem que, para a formação da biomassa e etanol, os fatores que mais interferiram foram a concentração de cloreto de sódio e a condição celular que influencia negativamente a produ

  3. Identification and Characterization of 5′ Untranslated Regions (5′UTRs in Zymomonas mobilis as Regulatory Biological Parts

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    Seung Hee Cho

    2017-12-01

    Full Text Available Regulatory RNA regions within a transcript, particularly in the 5′ untranslated region (5′UTR, have been shown in a variety of organisms to control the expression levels of these mRNAs in response to various metabolites or environmental conditions. Considering the unique tolerance of Zymomonas mobilis to ethanol and the growing interest in engineering microbial strains with enhanced tolerance to industrial inhibitors, we searched natural cis-regulatory regions in this microorganism using transcriptomic data and bioinformatics analysis. Potential regulatory 5′UTRs were identified and filtered based on length, gene function, relative gene counts, and conservation in other organisms. An in vivo fluorescence-based screening system was developed to confirm the responsiveness of 36 5′UTR candidates to ethanol, acetate, and xylose stresses. UTR_ZMO0347 (5′UTR of gene ZMO0347 encoding the RNA binding protein Hfq was found to down-regulate downstream gene expression under ethanol stress. Genomic deletion of UTR_ZMO0347 led to a general decrease of hfq expression at the transcript level and increased sensitivity for observed changes in Hfq expression at the protein level. The role of UTR_ZMO0347 and other 5′UTRs gives us insight into the regulatory network of Z. mobilis in response to stress and unlocks new strategies for engineering robust industrial strains as well as for harvesting novel responsive regulatory biological parts for controllable gene expression platforms in this organism.

  4. Application of fractional factorial design to levan production by Zymomonas mobilis Aplicação do planejamento fatorial fracionário para a produção de levana por Zymomonas mobilis

    Directory of Open Access Journals (Sweden)

    I.R. Melo

    2007-03-01

    Full Text Available Levan is a non-toxic, biologically active, extra cellular polysaccharide composed solely by fructose units. Optimization of levan production by Zymomonas mobilis strain ZAG-12 employing a 2(4-1 fractional factorial design was performed to analyze the influence of the temperature (20, 25 e 30ºC agitation (50, 75 e 100 rpm, and the initial concentrations of both sucrose (150, 200 e 250 g.L-1 and yeast extract (2.0, 3.5 e 5.0g.L-1 on final levan concentration. Aerobic fermentation was performed batchwise in 500mL Pyrex flasks for 72 hours. Biomass, ethanol, levan and sucrose were determined at beginning and also at end of the fermentations. The experiments showed that the final levan concentration depended on initial sucrose concentration, temperature and agitation velocity and that the initial concentration of yeast extract did not influence levan production. However, when the production of ethanol and biomass were considered, it became evident that yeast extract was a significant variable. The best conditions for levan production occurred at 100 rpm agitation, 20ºC and 250g.L-1 of initial sucrose resulting in 14.67g.L-1 of levan.Levana é um polissacarídeo extracelular, biologicamente ativo, não tóxico, contendo em sua estrutura apenas frutose. A maximização da produção de levana, por via fermentativa, pela linhagem de Zymomonas mobilis ZAG-12, foi estudada utilizando-se um planejamento fatorial de dois níveis 2(4-1, variando-se as concentrações iniciais de sacarose (150, 200 e 250 g.L-1 , extrato de levedura (2.0, 3.5 e 5.0 g.L-1, temperatura (20, 25 e 30ºC e agitação (50, 75 e 100 rpm. As fermentações foram desenvolvidas por processos descontínuos em frascos Pyrex roscados, de 500 mL, contendo 300 mL de meio a base de sacarose, por 72 horas. No início e ao final do processo, foram dosados: biomassa, etanol, levana e sacarose como açúcares redutores totais. A análise dos dados mostra que o aumento da produção de levana

  5. 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.

    Science.gov (United States)

    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

  6. Influence of carbon source and the fermentation process on levan production by Zymomonas mobilis analyzed by the surface response method Influência da fonte de carbono e do processo fermentativo na produção de levana por Zymomonas mobilis analisada pela metodologia de superfície de resposta

    Directory of Open Access Journals (Sweden)

    Raquel Renan Jorge Borsari

    2006-09-01

    Full Text Available The aim of this study is to assess sugar cane juice and sucrose as substrates, the batch and fed batch processes and their interaction in the levan production using a complete factorial design. Zymomonas mobilis was cultivated in different sugar cane juice and sucrose concentrations in two fermentation processes at 25 °C for 20 h. A complete factorial design (2³ was used to analyze the effects of the type and concentration of the substrate, as well as the batch and fed batch processes. A complete second factorial design (2² was used to observe the importance of sugar cane juice. The results indicated that the batch process improved the levan production reaching 40.14 g/L. The addition of sugar cane juice was not statistically significant for levan formation, however sugar cane juice stimulated biomass, sorbitol and ethanol production. The best medium for levan production was 150 g/L sucrose in batch.O presente estudo avaliou caldo de cana de açúcar e sacarose como substratos e os processos batelada e batelada alimentada e suas interações na produção de levana. Zymomonas mobilis foi cultivada em diferentes concentrações de caldo de cana de açúcar e sacarose nos dois processos fermentativos a 25 °C por 20 h. Foi utilizado um delineamento fatorial completo (23 para analisar os efeitos do tipo e concentração de substratos e processos batelada e batelada alimentada. Um segundo delineamento fatorial completo (22 foi usado para confirmar a importância do caldo de cana de açúcar. Os resultados indicam que o processo batelada foi o melhor para a produção de levana, atingindo 40,14 g/L em 150 g/L de sacarose. A adição de caldo de cana de açúcar não foi estatisticamente significativa para formação de levana, porém o caldo estimulou a produção de biomassa, sorbitol e etanol.

  7. Evaluation of supplementation of sucrose medium on the synthesis of Zymomonas mobilis bio-products - doi: 10.4025/actascibiolsci.v32i3.1519

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    Maria Antonia Pedrini Colabone Celligoi

    2010-09-01

    Full Text Available The effect of the variables pantothenic acid, yeast extract and sodium chloride, as well as the cell permeabilization technique, were investigated on the formation of levan, ethanol, sorbitol and biomass of Zymomonas mobilis, using a 24-1 fraction factorial design. Cell growth was determined by turbidimetry at 605 nm, relating it to a biomass with a dry weight calibration curve. Reducing sugars were quantified according to Somogyi and Nelson. Total sugars were quantified by the phenol-sulfuric acid method, sorbitol by HPLC and ethanol. The levan produced was precipitated by the addition of absolute ethanol and quantified in fructose units. In levan biosynthesis, the variable that had the largest contribution was cell condition. The results suggested that the factors that most affected biomass and ethanol formation were sodium chloride concentration and cell condition that affected negatively on production. For sorbitol, the variable that had a significant effect was permeabilization, which decreased its synthesis. Studies to amplify the range of established factors would be important.The effect of the variables pantothenic acid, yeast extract and sodium chloride, as well as the cell permeabilization technique, were investigated on the formation of levan, ethanol, sorbitol and biomass of Zymomonas mobilis, using a 24-1 fraction factorial design. Cell growth was determined by turbidimetry at 605 nm, relating it to a biomass with a dry weight calibration curve. Reducing sugars were quantified according to Somogyi and Nelson. Total sugars were quantified by the phenol-sulfuric acid method, sorbitol by HPLC and ethanol. The levan produced was precipitated by the addition of absolute ethanol and quantified in fructose units. In levan biosynthesis, the variable that had the largest contribution was cell condition. The results suggested that the factors that most affected biomass and ethanol formation were sodium chloride concentration and cell

  8. Hybrid neural network model for simulating sorbitol synthesis by glucose-fructose oxidoreductase in Zymomonas mobilis CP4

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    Bravo S.

    2004-01-01

    Full Text Available A hybrid neural network model for simulating the process of enzymatic reduction of fructose to sorbitol process catalyzed by glucose-fructose oxidoreductase in Zymomonas mobilis CP4 is presented. Data used to derive and validate the model was obtained from experiments carried out under different conditions of pH, temperature and concentrations of both substrates (glucose and fructose involved in the reaction. Sonicated and lyophilized cells were used as source of the enzyme. The optimal pH for sorbitol synthesis at 30º C is 6.5. For a value of pH of 6, the optimal temperature is 35º C. The neural network in the model computes the value of the kinetic relationship. The hybrid neural network model is able to simulate changes in the substrates and product concentrations during sorbitol synthesis under pH and temperature conditions ranging between 5 and 7.5 and 25 and 40º C, respectively. Under these conditions the rate of sorbitol synthesis shows important differences. Values computed using the hybrid neural network model have an average error of 1.7·10-3 mole.

  9. The effects of potassium and chloride ions on the ethanolic fermentation of sucrose by Zymomonas mobilis 2716

    Energy Technology Data Exchange (ETDEWEB)

    Kirk, L A; Doelle, H W [Queensland Univ., Brisbane (Australia). Dept. of Microbiology

    1992-04-01

    The inclusion of specific salts in Zymomonas mobilis batch sucrose fermentations can limit by-product formation. Sorbitol and fructo-oligosaccharide formation can be reduced and ethanol production enhanced by manipulating mineral salt concentrations. Chloride salts reduced the production of biomass and sorbitol in favour of fructo-obligosaccharide formation at concentrations lower than 10 g NaCl/l or MgCl{sub 2}. Higher concentrations led to the accumulation of glucose and fructose. Low concentrations of KH{sub 2}PO{sub 4} (<20 g/l) enhanced biomass formation, and the concomitant reduction in sorbitol and fructo-obligosaccharides favoured enhanced ethanol formation. At concentrations above 20 g/l, its effects were similar to those obtained with the chloride salts. Invertase addition at the start of fermentation increased sorbitol formation, whereas addition after the completion of sucrose hydrolysis resulted in the conversion of fructo-obligosaccharides formed into fructose or ethanol. Fermentation with 250 g/l of sugar-cane syrup (=130 g sucrose/l) in the presence of 8 g KH{sub 2}PO{sub 4}/l, with 0.05 g invertase/l added on the completion of sucrose hydrolysis, resulted in a conversion efficiency of 94% with complete carbon accountability, and only 7 g sorbitol/l. (orig.).

  10. Produção de L-asparaginase por Zymomonas mobilis durante a fermentação do melaço: otimização das condições de cultivo utilizando delineamento fatorial - DOI: 10.4025/actascitechnol.v28i2.1178

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    Doumit Camilios Neto

    2006-03-01

    Full Text Available A L-asparaginase é uma enzima com atividade anti-leucêmica produzida por microrganismos, principalmente bactérias gram-negativas. Zymomonas mobilis é uma bactéria gram-negativa, que apresenta potencial para produção de L-asparaginase. Esse estudo buscou a otimização da produção de L-asparaginase por Zymomonas mobilis, durante a fermentação do melaço de cana-de-açúcar, utilizando um delineamento fatorial incompleto 33. O modelo obtido através da metodologia de superfície de resposta foi otimizado pelo software Otplex. Obteve-se bom ajuste do modelo aos dados experimentais, sendo o coeficiente de determinação total (R2, 95%. A máxima atividade enzimática (16,55 UI L-1 foi obtida com uma concentração de açúcares redutores totais no melaço de 100,0 g L-1, 2,0 g L-1 de extrato de levedura e com 21 horas de fermentação. A validação experimental confirmou a capacidade preditiva do modelo, sendo a diferença entre resposta estimada(Ŷ1 e resposta observada (Y1 apenas de 1%.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  13. Optimization of process parameters for ethanol production from sugar cane molasses by Zymomonas mobilis using response surface methodology and genetic algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Maiti, Bodhisatta; Shekhawat, Mitali; Srivastava, Pradeep [Banaras Hindu Univ., Varanasi (India). School of Biochemical Engineering; Rathore, Ankita [Nizam College, Hyderabad (India). Dept. of Biotechnology; Srivastava, Saurav [National Institute of Technology, Durgapur (India). Dept. of Biotechnology

    2011-04-15

    Ethanol is a potential energy source and its production from renewable biomass has gained lot of popularity. There has been worldwide research to produce ethanol from regional inexpensive substrates. The present study deals with the optimization of process parameters (viz. temperature, pH, initial total reducing sugar (TRS) concentration in sugar cane molasses and fermentation time) for ethanol production from sugar cane molasses by Zymomonas mobilis using Box-Behnken experimental design and genetic algorithm (GA). An empirical model was developed through response surface methodology to analyze the effects of the process parameters on ethanol production. The data obtained after performing the experiments based on statistical design was utilized for regression analysis and analysis of variance studies. The regression equation obtained after regression analysis was used as a fitness function for the genetic algorithm. The GA optimization technique predicted a maximum ethanol yield of 59.59 g/L at temperature 31 C, pH 5.13, initial TRS concentration 216 g/L and fermentation time 44 h. The maximum experimental ethanol yield obtained after applying GA was 58.4 g/L, which was in close agreement with the predicted value. (orig.)

  14. An evolved xylose transporter from Zymomonas mobilis enhances sugar transport in Escherichia coli

    Directory of Open Access Journals (Sweden)

    Zhang Jingqing

    2009-12-01

    Full Text Available Abstract Background Xylose is a second most abundant sugar component of lignocellulose besides glucose. Efficient fermentation of xylose is important for the economics of biomass-based biorefineries. However, sugar mixtures are sequentially consumed in xylose co-fermentation with glucose due to carbon catabolite repression (CCR in microorganisms. As xylose transmembrance transport is one of the steps repressed by CCR, it is therefore of interest to develop a transporter that is less sensitive to the glucose inhibition or CCR. Results The glucose facilitator protein Glf transporter from Zymomonas mobilis, also an efficient transporter for xylose, was chosen as the target transporter for engineering to eliminate glucose inhibition on xylose uptake. The evolution of Glf transporter was carried out with a mixture of glucose and xylose in E. coli. Error-prone PCR and random deletion were employed respectively in two rounds of evolution. Aided by a high-throughput screening assay using xylose analog p-nitrophenyl-β-D-xylopyranoside (pNPX in 96-well plates, a best mutant 2-RD5 was obtained that contains several mutations, and a deletion of 134 residues (about 28% of total residues, or three fewer transmembrane sections (TMSs. It showed a 10.8-fold improvement in terms of pNPX transport activity in the presence of glucose. The fermentation performance results showed that this mutant improved xylose consumption by 42% with M9 minimal medium containing 20 g L-1 xylose only, while with the mixture sugar of xylose and glucose, 28% more glucose was consumed, but no obvious co-utilization of xylose was observed. Further glucose fed-batch experiments suggested that the intracellular metabolism of xylose was repressed by glucose. Conclusions Through random mutagenesis and partial deletion coupled with high-throughput screening, a mutant of the Glf transporter (2-RD5 was obtained that relieved the inhibition of xylose transport by glucose. The fermentation

  15. Development of High-Productivity Continuous Ethanol Production using PVA-Immobilized Zymomonas mobilis in an Immobilized-Cells Fermenter

    Directory of Open Access Journals (Sweden)

    Nurhayati Nurhayati

    2015-07-01

    Full Text Available Ethanol as one of renewable energy was being considered an excellent alternative clean-burning fuel to replace gasoline. Continuous ethanol fermentation systems had offered important economic advantages compared to traditional systems. Fermentation rates were significantly improved, especially when continuous fermentation was integrated with cell immobilization techniques to enrich the cells concentration in fermentor. Growing cells of Zymomonas mobilis immobilized in polyvinyl alcohol (PVA gel beads were employed in an immobilized-cells fermentor for continuous ethanol fermentation from glucose. The glucose loading, dilution rate, and cells loading were varied in order to determine which best condition employed in obtaining both high ethanol production and low residual glucose with high dilution rate. In this study, 20 g/L, 100 g/L, 125 g/L and 150 g/L of glucose concentration and 20% (w/v, 40% (w/v and 50% (w/v of cells loading were employed with range of dilution rate at 0.25 to 1 h-1. The most stable production was obtained for 25 days by employing 100 g/L of glucose loading. Meanwhile, the results also exhibited that 125 g/L of glucose loading as well as 40% (w/v of cells loading yielded high ethanol concentration, high ethanol productivity, and acceptable residual glucose at 62.97 g/L, 15.74 g/L/h and 0.16 g/L, respectively. Furthermore, the dilution rate of 4 hour with 100 g/L and 40% (w/v of glucose and cells loading was considered as the optimum condition with ethanol production, ethanol productivity and residual glucose obtained were 49.89 g/L, 12.47 g/L/h, and 2.04 g/L, respectively. This recent study investigated ethanol inhibition as well. The present research had proved that high sugar concentration was successfully converted to ethanol. These achieved results were promising for further study.

  16. Production of ethanol from mesquite [Prosopis juliflora (SW) D.C.] pods mash by Zymomonas mobilis in submerged fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Celiane Gomes Maia da [Universidade Federal Rural de Pernambuco (UFRPE), Recife, PE (Brazil). Dept. de Ciencias Domesticas; Andrade, Samara Alvachian Cardoso; Schuler, Alexandre Ricardo Pereira [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Engenharia Quimica; Souza, Evandro Leite de [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Dept. de Nutricao; Stamford, Tania Lucia Montenegro [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Nutricao], E-mail: tlmstamford@yahoo.com.br

    2011-01-15

    Mesquite [Prosopis juliflora (SW) D.C.], a perennial tropical plant commonly found in Brazilian semi-arid region, is a viable raw material for fermentative processes because of its low cost and production of pods with high content of hydrolyzable sugars which generate many compounds, including ethanol. This study aimed to evaluate the use of mesquite pods as substrate for ethanol production by Z. mobilis UFPEDA- 205 in a submerged fermentation. The fermentation was assessed for rate of substrate yield to ethanol, rate of ethanol production and efficiency of fermentation. The very close theoretical (170 g L{sup -1}) and experimental (165 g L{sup -1}) maximum ethanol yields were achieved at 36 h of fermentation. The highest counts of Z. mobilis UFEPEDA-205 (both close to 6 Log cfu mL{sup -1}) were also noted at 36 h. Highest rates of substrate yield to ethanol (0.44 g ethanol g glucose{sup -1}), of ethanol production (4.69 g L{sup -1} h{sup -1}) and of efficiency of fermentation (86.81%) were found after 30 h. These findings suggest mesquite pods as an interesting substrate for ethanol production using submerged fermentation by Z. mobilis. (author)

  17. ORF Alignment: NC_006526 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available ltransferase [Zymomonas mobilis subsp. mobilis ... ZM4] ... Length = 162 ... Query: 11 ... IALYPGTFDPVTLGHLDIIRRGARIFD...HLIIAVAENPGKSPLFSSEERASMIRHEISRLE 70 ... IALYPGTFDPVTLGHLDIIRRGARIFD...HLIIAVAENPGKSPLFSSEERASMIRHEISRLE Sbjct: 1 ... IALYPGTFDPVTLGHLDIIRRGARIFDHLIIAVAENPGKSPLFSSEERASM

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

    Science.gov (United States)

    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.

  19. Production of ethanol from mesquite [Prosopis juliflora (SW D.C.] pods mash by Zymomonas mobilis in submerged fermentation Produção de etanol a partir do mosto de vagens de algaroba [Prosopis juliflora (SW D.C.] por Zymomonas mobilis em fermentação submersa

    Directory of Open Access Journals (Sweden)

    Celiane Gomes Maia da Silva

    2011-02-01

    Full Text Available Mesquite [Prosopis juliflora (SW D.C.], a perennial tropical plant commonly found in Brazilian semi-arid region, is a viable raw material for fermentative processes because of its low cost and production of pods with high content of hydrolysable sugars which generate many compounds, including ethanol. This study aimed to evaluate the use of mesquite pods as substrate for ethanol production by Z. mobilis UFPEDA205 in a submerged fermentation. The fermentation was assessed for rate of substrate yield to ethanol, rate of ethanol production and efficiency of fermentation. The very close theoretical (170 g L-1 and experimental (165 g L-1 maximum ethanol yields were achieved at 36 h of fermentation. The highest counts of Z. mobilis UFEPEDA-205 (both close to 6 Log cfu mL-1 were also noted at 36 h. Highest rates of substrate yield to ethanol (0.44 g ethanol g glucose-1, of ethanol production (4.69 g L-1 h-1 and of efficiency of fermentation (86.81% were found after 30 h. These findings suggest mesquite pods as an interesting substrate for ethanol production using submerged fermentation by Z. mobilis.A algaroba [Prosopis juliflora (SW D.C.] é uma planta tropical perene comumente encontrada no semi-árido brasileiro e apresenta-se como matéria-prima viável para o processo fermentativo por possuir baixo custo e para produzir vagens que contém um elevado teor de açúcares hidrolisáveis, os quais podem gerar diversos compostos, incluindo etanol. Avaliou-se o uso de vagens de algaroba como substrato para produção de etanol por Z. mobilis UFPEDA-205 por meio de fermentação submersa. O processo fermentativo foi avaliado por meio da mensuração da taxa de conversão de substrato em etanol, taxa de produção de etanol e eficiência de fermentação. Os valores muito próximos encontrados para o fornecimento máximo teórico (170 g L-1 e experimental (165 g L-1 de etanol foram alcançados após 36 h de fermentação. O valor de contagem experimental

  20. Pantothenic acid biosynthesis in zymomonas

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Luan; Tomb, Jean-Francois; Viitanen, Paul V.

    2014-07-01

    Zymomonas is unable to synthesize pantothenic acid and requires this essential vitamin in growth medium. Zymomonas strains transformed with an operon for expression of 2-dehydropantoate reductase and aspartate 1-decarboxylase were able to grow in medium lacking pantothenic acid. These strains may be used for ethanol production without pantothenic acid supplementation in seed culture and fermentation media.

  1. Effect of the presence of initial ethanol on ethanol production in sugar cane juice fermented by Zymomonas mobilis

    OpenAIRE

    Tano,Marcia Sadae; Buzato,João Batista

    2003-01-01

    Ethanol production in sugar cane juice in high initial sugar concentration, fermented by Z. mobilis in the presence and absence of ethanol, was evaluated. Ethanol production was low in both media. The presence of initial ethanol in the sugar cane juice reduced ethanol production by 48.8%, biomass production by 25.0% and the total sugar consumption by 28.3%. The presence of initial ethanol in the medium did not affect significantly levan production and biomass yield coefficient (g biomass/g su...

  2. Continuous fermentation using low concentration of sugar cane and Zymomonas mobilis CP4 for ethanol production

    Directory of Open Access Journals (Sweden)

    João Batista Buzato

    2001-01-01

    Full Text Available Effect of dilution rate in continuous fermentation of 20g sucrose/L and Z. mobilis CP4 was studied for ethanol production at 28oC + 1, without pH control. Four dilution rates were compared: 0.045; 0.14; 0.23 and 0.34 h-1. In dilution rates 0.045; 0.14 and 0.23 h-1 were produced 9,4g/L of ethanol and in dilution rate 0.34 h-1 was produced 8,8 g/L. Ethanol conversion efficiency were of 91% in dilution rates 0.045; 0.14 and 0. 23 h-1. In dilution rate 0.34 h-1 the conversion efficiency was of 85%.

  3. Respective effects of sodium and chloride ion on physiological ...

    African Journals Online (AJOL)

    Respective effects of sodium and chloride ion on growth, cell morphological changes, membrane disorganization, ion homeostasis, exoenzyme activities and fermentation performance in Zymomonas mobilis232B cultures were presented. In batch cultures containing 0.15 M NaCl, Z. mobilis232B developed filaments, and ...

  4. Calcium chloride improve ethanol production in recombinant ...

    African Journals Online (AJOL)

    The T7-expression system has been very useful for protein expression in Escherichia coli. Here, a T7- expression transposon was constructed, which allowed simple construction of T7-expression Zymomonas mobilis. This transposon contained the T7 RNA polymerase being driven by the gap promoter from Z. mobilis.

  5. Didemnin Biosynthetic Gene Cluster In Tistrella Mobilis

    KAUST Repository

    Qian, Pei-Yuan; Xu, Ying Sharon; Lai, Pok-Yui

    2014-01-01

    A novel Tistrella mobilis strain having Accession Deposit Number NRRL B-50531 is provided. A method of producing a didemnin precursor, didemnin or didemnin derivative by using the Tistrella mobilis strain, and the therapeutic composition comprising

  6. Food Grade Ehanol Production With Fermentation And Distillation Process Using Stem Sorghum

    Directory of Open Access Journals (Sweden)

    Yuliana Setyowati

    2015-03-01

    Full Text Available 10% -12% of sugar in its stem which is the optimum sugar concentration in fermentation process for bioethanol production. Sorghum has a high potential to be developed as a raw material for food-grade ethanol production which can be used to support food-grade ethanol demand in Indonesia through a fermentation process. This research focused on the effect of microorganism varieties in the fermentation process which are mutant Zymomonas mobilis (A3, Saccharomyces cerevisiae and Pichia stipitis mixture. The Research for purification process are separated into two parts, distillation with steel wool structured packing and dehydration process using molecular sieve and eliminating impurities using activated carbon. The research can be concluded that the best productivity shown in continuous fermentation in the amount of 84.049 (g / L.hr using the mixture of Saccharomyces cerevisiae and Pichia stipitis. The highest percentage of ethanol yield produced in batch fermentation using the mixture of Saccharomyces cerevisiae and Pichia stipitis that is equal to 51.269%. And for the adsorption, the best result shown in continuous fermentation by using Zymomonas Mobilis of 88.374%..

  7. Didemnin Biosynthetic Gene Cluster In Tistrella Mobilis

    KAUST Repository

    Qian, Pei-Yuan

    2014-10-02

    A novel Tistrella mobilis strain having Accession Deposit Number NRRL B-50531 is provided. A method of producing a didemnin precursor, didemnin or didemnin derivative by using the Tistrella mobilis strain, and the therapeutic composition comprising at least one didemnin or didemnin derivative produced from the strain or modified strain thereof are also provided.

  8. Xylose utilization in recombinant zymomonas

    Science.gov (United States)

    Caimi, Perry G; McCole, Laura; Tao, Luan; Tomb, Jean-Francois; Viitanen, Paul V

    2014-03-25

    Xylose-utilizing Zymomonas strains studied were found to accumulate ribulose when grown in xylose-containing media. Engineering these strains to increase ribose-5-phosphate isomerase activity led to reduced ribulose accumulation, improved growth, improved xylose utilization, and increased ethanol production.

  9. Browse Title Index

    African Journals Online (AJOL)

    Items 4751 - 4800 of 11090 ... Vol 10, No 62 (2011), Evaluation of drought tolerance in different ... Vol 15, No 30 (2016), Evaluation of ethanol production from pito mash using Zymomonas mobilis and Saccharomyces cerevisiae, Abstract PDF.

  10. Comparative study of bioethanol production from sugarcane ...

    African Journals Online (AJOL)

    The study was designed to compare the bioethanol production from Zymomonas mobilis and Saccharomyces cerevisiae using molasses as production medium. The focus was on the retention time at lab scale. Bioethanol and petroleum blend can be used in existing gasoline engines. Present study showed a more ...

  11. Nancy Dowe | NREL

    Science.gov (United States)

    Bench scale integration and scale up of biological processes to produce fuels and chemicals from Zymomonas mobilis strain 8b through continuous adaptation on dilute acid pretreated corn stover hydrolysate development and integration. Please do NOT contact me directly for jobs-see instead information on NREL's

  12. Alcohol production from pineapple waste

    Energy Technology Data Exchange (ETDEWEB)

    Ban-Koffi, L. (Ministry of Scientific Research, Abidjan (CI). Ivorian Center of Technological Research); Han, Y.W. (USDA, Southern Regional Research Center, New Orleans, LA (US))

    1990-09-01

    Saccharomyces cerevisiae and Zymomonas mobilis were grown on pineapple waste and their alcohol production characteristics compared. The pineapple waste consisted of 19% cellulose, 22% hemi-cellulose, 5% lignin and 53% cell soluble matters but concentration of soluble sugars, which included 5.2% sucrose, 3.1% glucose and 3.4% fructose, was relatively low and pretreatment of the substrate was needed. Pretreatment of pineapple waste with cellulase and hemi-cellulase and then fermentation with S. cerevisiae or Z. mobilis produced about 8% ethanol from pineapple waste in 48 h. (author).

  13. High production of fructooligosaccharides by levansucrase from ...

    African Journals Online (AJOL)

    SAM

    2014-07-02

    Jul 2, 2014 ... production activity of Zymomonas mobilis extracellular levansucrase. Process. Biochem. 38:701-706. http://dx.doi.org/10.1016/S0032-. 9592(02)00189-9. Belghith KM, Dahech I, Belghith H, Mejoud H (2012). Microbial production of levansucrase for synthesis of fructo-oligosaccharide. Int. J. Biol. Macromol.

  14. Reproductive performance of female goats fed life-enzyme ...

    African Journals Online (AJOL)

    Direct-fed-microbes (DFM) (life-enzyme) was prepared in a traditional setting using Zymomonas mobilis (bacteria from palm sap) to ferment sawdust. The result revealed an improvement in the nutrient content of the sawdust and its feed values (protein, fibre etc.), and the feed usage efficiency. The reproductive ...

  15. Biological conversion system

    Science.gov (United States)

    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.

  16. Le tecnologie mobili dell’apprendimento permanente, il progetto MOTILL

    Directory of Open Access Journals (Sweden)

    Marco Arrigo

    2013-03-01

    Full Text Available In questo articolo vengono presentati alcuni dei risultati del progetto MOTILL. MOTILL, ovvero «Le Tecnologie Mobili nell’apprendimento permanente: buone pratiche», è un progetto finanziato dalla Comunità Europea, nell’ambito del National Lifelong Learning Strategies (NLLS. Il progetto, durato un anno e terminato a Marzo 2010, si è focalizzato sull’uso delle tecnologie mobili in contesti di lifelong learning (LLL. L’articolo sarà dedicato a una breve introduzione del progetto, dei suoi obiettivi e delle azioni portate avanti, e a un rapido riassunto dei principali risultati ottenuti, i quali sono stati resi disponibili online alla comunità scientifica e diffusi ai policy makers impegnati nei programmi di apprendimento permanente.

  17. Global occurrence and heterogeneity of the Roseobacter-clade species Ruegeria mobilis

    DEFF Research Database (Denmark)

    Sonnenschein, Eva; Nielsen, Kristian Fog; D'Alvise, Paul

    2017-01-01

    in the free-living fraction occurring in 40% and 6% of the samples, respectively. Our data and the TARA data, although lacking sufficient data from the polar regions, demonstrate that R. mobilis is a globally distributed marine bacterial species found primarily in the upper open oceans. It has preserved key....... Major genomic differences within the sub-clusters include prophages and toxin-antitoxin systems. In general, the genome of R. mobilis revealed adaptation to a particle-associated life style and querying TARA ocean data confirmed that R. mobilis is more abundant in the particle-associated fraction than...

  18. Ethanol production using xylitol synthesis mutant of xylose-utilizing zymomonas

    Science.gov (United States)

    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.

  19. ORF Alignment: NC_003384 [GENIUS II[Archive

    Lifescience Database Archive (English)

    Full Text Available [Zymomonas mobilis] gb|AAQ67239.1| ... Bla [Transposon delivery vector pUT-miniTn5-gfp-tet] ... ... ... 3.5.2.6) precursor - Escherichia coli plasmids ... gb|AAC79082.1| beta lactamase [Transposon delivery...AG47772.1| beta-lactamase ... TEM-1 [Klebsiella pneumoniae] gb|AAG37887.1| ampicillin ... resistance [Tn10 delivery... vector pHV1249] gb|AAG37882.1| ... ampicillin resistance [Tn10 delivery

  20. Xylitol synthesis mutant of xylose-utilizing zymomonas for ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. Ethanol production of banana shell and cassava starch

    International Nuclear Information System (INIS)

    Monsalve G, John F; Medina de Perez, Victoria Isabel; Ruiz colorado, Angela Adriana

    2006-01-01

    In this work the acid hydrolysis of the starch was evaluated in cassava and the cellulose shell banana and its later fermentation to ethanol, the means of fermentation were adjusted for the microorganisms saccharomyces cerevisiae nrrl y-2034 and zymomonas mobilis cp4. The banana shell has been characterized, which possesses a content of starch, cellulose and hemicelluloses that represent more than 80% of the shell deserve the study of this as source of carbon. The acid hydrolysis of the banana shell yield 20g/l reducing sugar was obtained as maximum concentration. For the cassava with 170 g/l of starch to ph 0.8 in 5 hours complete conversion is achieved to you reducing sugars and any inhibitory effect is not noticed on the part of the cultivations carried out with banana shell and cassava by the cyanide presence in the cassava and for the formation of toxic compounds in the acid hydrolysis the cellulose in banana shell. For the fermentation carried out with saccharomyces cerevisiae a concentration of ethanol of 7.92± 0.31% it is achieved and a considerable production of ethanol is not appreciated (smaller than 0.1 g/l) for none of the means fermented with zymomonas mobilis

  2. Pnp gene modification for improved xylose utilization in Zymomonas

    Science.gov (United States)

    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.

  3. Use of Saccharomyces cerevisiae and Zymomonas mobilis for ...

    African Journals Online (AJOL)

    Biofuels have received great attention as an alternative energy source mainly due to limited oil reserves. Bioethanol can be produced from wide range of raw materials like starch, sucrose and cellulosic based sources. Sugar beet and raw juice, as its intermediate product, constitute very profitable substrates for bioethanol ...

  4. Rewiring Lactococcus lactis for Ethanol Production

    DEFF Research Database (Denmark)

    Solem, Christian; Dehli, Tore Ibsen; Jensen, Peter Ruhdal

    2013-01-01

    to redirect the metabolism of LAB model organism Lactococcus lactis toward ethanol production. Codon-optimized Zymomonas mobilis pyruvate decarboxylase (PDC) was introduced and expressed from synthetic promoters in different strain backgrounds. In the wild-type L. lactis strain MG1363 growing on glucose, only...... small amounts of ethanol were obtained after introducing PDC, probably due to a low native alcohol dehydrogenase activity. When the same strains were grown on maltose, ethanol was the major product and lesser amounts of lactate, formate, and acetate were formed. Inactivating the lactate dehydrogenase...... genes ldhX, ldhB, and ldh and introducing codon-optimized Z. mobilis alcohol dehydrogenase (ADHB) in addition to PDC resulted in high-yield ethanol formation when strains were grown on glucose, with only minor amounts of by-products formed. Finally, a strain with ethanol as the sole observed...

  5. Manual de boas práticas ambientais para a indústria do mobiliário de madeira

    OpenAIRE

    Ribeiro, Ricardo Cristiano Peixoto

    2015-01-01

    Este trabalho tem como finalidade a elaboração de um projeto na área ambiental denominado Manual de Boas Práticas Ambientais para a Indústria do Mobiliário de Madeira. Para conseguir atingir o objetivo proposto, inicialmente foi efetuado um breve enquadramento ao subsetor do mobiliário de madeira a nível nacional, recorrendo à bibliografia disponível apoiada em dados estatísticos de suporte. Foram caracterizados os dois concelhos alvo de estudo, Paços de Ferreira e Paredes por ...

  6. Fermentation potentials of Zymomonas mobilis and its application in ...

    African Journals Online (AJOL)

    GREGORY

    2010-09-13

    Sep 13, 2010 ... rate and lower biomass (Rogers et al., 2007; Jeffries,. 2005; Rogers et al., ... above experiments were performed twice with three repeats. Sweet potato material and ..... design trends and integration opportunities. Bioresour. ... Eckert CA, Frederick Jr. WJ, Hallett JP, Leak DJ, Liotta CL, Mielenz. JR, Murphy R ...

  7. Exometabolomics Assisted Design and Validation of Synthetic Obligate Mutualism.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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).

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

    Science.gov (United States)

    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.

  11. Economic and process optimization of ethanol production by extractive fermentation

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This report demonstrates by computer simulation the economic advantages of extractive fermentation on an industrial scale compared to the best alternative technology currently available. The simulations were based on a plant capacity of 100 x 10 6 L/y of azeotropic ethanol. The simulation results were verified with a fully integrated, computer controlled extractive fermentation process demonstration unit based around a 7 L fermentor operated with a synthetic glucose medium and using Saccharomyces cerevisiae. The system was also operated with natural substrates (blackstrap molasses and grain hydrolyzate). Preliminary tests with the organism Zymomonas mobilis were also carried out under extractive fermentation conditions.

  12. Biofilm formation and antibiotic production in Ruegeria mobilis are influenced by intracellular concentrations of cyclic dimeric guanosinmonophosphate

    DEFF Research Database (Denmark)

    D'Alvise, Paul; Magdenoska, Olivera; Melchiorsen, Jette

    2014-01-01

    species Ruegeria mobilis are associated with intracellular concentrations of the signal compound cyclic dimeric guanosinmonophosphate (c-di-GMP), which in bacteria regulates transitions between motile and sessile life stages. Genes for diguanylate cyclases and phosphodiesterases, which are involved in c-di-GMP...... signalling, were found in the genome of R. mobilis strain F1926. Ion pair chromatography-tandem mass spectrometry revealed 20-fold higher c-di-GMP concentrations per cell in biofilm-containing cultures than in planktonic cells. An introduced diguanylate cyclase gene increased c-di-GMP and enhanced biofilm...... formation and production of the potent antibiotic tropodithietic acid (TDA). An introduced phosphodiesterase gene decreased c-di-GMP and reduced biofilm formation and TDA production. tdaC, a key gene for TDA biosynthesis, was expressed only in attached or biofilm-forming cells, and expression was induced...

  13. Cells on corrugations for pollution control

    International Nuclear Information System (INIS)

    Clyde, R.

    1993-01-01

    Old cardboard boxes constitute 12% of landfills. White rot fungus can be grown on the boxes and buried in contaminated soil. The fungus needs air which is entrapped in the corrugations. The fungus is sensitive to large amounts of TNT but it is protected when inside the corrugations. Fast food containers are filling landfills. Lactic acid production needs air and the polymers are biodegradable. When corrugations are put in a half full rotary unit, holes in the valleys make drops, and mass transfer to drops is much higher than to a flat surface. A lab corrugator has been made from an old washing machine wringer, so other fibers can be corrugated. When the bacterium, Zymomonas mobilis is grown on Tyvek fiber, lead and six valent chromium are removed from wastewater in a few seconds. Zymomonas on rotating fibers converts sugar to alcohol in 10--15 minutes and when a light is shown into flat rotating discs, it hits a thin moving film to destroy dioxin. Salt on roads causes millions of dollars damage to bridges and cars but calcium magnesium acetate is not corrosive and can be made with cells on rotating fibers

  14. Fermentative performance of bacteria and yeasts in lignocellulose hydrolysates

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, Lisbeth; Hahn-Haegerdal, B. (Lund Univ. (Sweden). Dept. of Applied Microbiology)

    1993-01-01

    The sugar consumption rates and the product formation of yeasts (Saccharomyces cidri NCYC 775, S. cerevisiae NCYC 1047, S.cerevisiae ATCC 4132) and bacteria (Lactobacillus brevis DSM 20054, Lactococcus lactis ssp. lactis ATCC 19435, Escherichia coli ATCC 11303, Zymomonas mobilis ATCC 31821) were investigated in spent sulphite liquor and an enzymatic hydrolysate of steam-pretreated Salix caprea at different pH values in order to elucidate the suitability of the organisms with respect to future genetic engineering approaches. The possible inhibitory action of the two substrates on the investigated microorganisms was also considered. S.cerevisiae emerged as one of the better candidates, owing to its fast sugar consumption rate and efficient ethanol production. (author)

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

    Science.gov (United States)

    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

  16. Associação entre sensação de dor e desconforto pelos segmentos corporais, postura sentada do aluno em sala de aula e o mobiliário escolar (cadeira/mesa

    Directory of Open Access Journals (Sweden)

    Valdemir Galvão de Carvalho

    2008-09-01

    Full Text Available Na sala de aula é comum os alunos adotarem posturas inadequadas por tempo prolongado que conduzem ao desconforto muscular. O objetivo proposto é investigar associações entre dores no corpo e o mobiliário da sala de aula. Foi desenvolvida pesquisa aplicada, descritiva e quanti-qualitativa, amostra probabilística aleatória simples e questionário com 290 alunos, de 05 cursos de uma IES; as técnicas estatísticas foram análise descritiva, clusters e qui-quadrado com p ≤ 0,05. 64,2% dos alunos consideraram o mobiliário desconfortável; para 62%, a localização dos recursos didáticos não permite boa acomodação postural; para 84,5%, a altura e o assento das carteiras são desconfortáveis. Os resultados sugerem associação entre dores na região lombar, ombro, quadril, nuca, costas, pernas e joelhos em relação à ausência de regulagens antropométricas no mobiliário e a localização dos equipamentos didáticos.

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

    Science.gov (United States)

    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.

  18. Microbial stress tolerance for biofuels. Systems biology

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zonglin Lewis (ed.) [National Center for Agricultural Utilization Research, USDA-ARS, Peoria, IL (United States)

    2012-07-01

    The development of sustainable and renewable biofuels is attracting growing interest. It is vital to develop robust microbial strains for biocatalysts that are able to function under multiple stress conditions. This Microbiology Monograph provides an overview of methods for studying microbial stress tolerance for biofuels applications using a systems biology approach. Topics covered range from mechanisms to methodology for yeast and bacteria, including the genomics of yeast tolerance and detoxification; genetics and regulation of glycogen and trehalose metabolism; programmed cell death; high gravity fermentations; ethanol tolerance; improving biomass sugar utilization by engineered Saccharomyces; the genomics on tolerance of Zymomonas mobilis; microbial solvent tolerance; control of stress tolerance in bacterial host organisms; metabolomics for ethanologenic yeast; automated proteomics work cell systems for strain improvement; and unification of gene expression data for comparable analyses under stress conditions. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Nghiem, NP

    2003-11-16

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

  20. Les structures et le mobilier du site d’habitat Hallstatt final-La Tène ancienne d'Allaines Mervilliers (Eure-et-Loir Buildings and effects from the hallstatt D-Early La Tène site of Allaines Mervilliers (Eure-et-Loir

    Directory of Open Access Journals (Sweden)

    Diane Casadei

    2006-12-01

    Full Text Available Découverte de structures d’habitat sur poteaux et d’une fosse Hallstatt final-La Tène ancienne dans le cadre d’une opération d’archéologie préventive en 1998, à Allaines Mervilliers (Eure-et-Loir. Il s’agit de deux bâtiments rectangulaires à six trous de poteau, d’un bâtiment rectangulaire à trois nefs et d’un bâtiment circulaire. Ces deux derniers sont inédits pour cette époque en région Centre. Le bâtiment rectangulaire à trois nefs est composé de deux rangées centrales de trois trous de poteau et de deux rangées latérales de quatre trous de poteau. Les trous de poteau centraux présentent un remplissage stratifié dont la couche supérieure a livré l’essentiel de l’abondant mobilier découvert. On décompte par exemple dans les vestiges en céramique 56 individus-vases différents. Le bâtiment circulaire est composé d’une couronne de neuf trous de poteau présentant également un remplissage stratifié. On a découvert moins de mobilier dans cette structure que dans le bâtiment précédent, mais il se singularise aussi par la présence d’ossements humains.The discovery of settlement structureson posts and of a pit Hallstatt D-early La Tène during a rescue archaeology operation in 1998, in Allaines Mervilliers (Eure-et-Loir. It concerned two rectangular buildings of six post holes, a rectangular building in three naves and a circular building. The latter two are new for this period in the Centre region.The rectangular building in three naves consisted of two central rows of three post holes and two lateral rows of four post holes. The central holes of post introduce a stratified fill, the upper layer of which produced the majority of the abundant finds. From the ceramic remains it was estimated that there were fifty-six individuals in different vases. The circular building consisted of a ring of nine post holes also producing a stratified fill. Fewer articles were discovered in this structure than

  1. Environmental Factors Modulating the Stability and Enzymatic Activity of the Petrotoga mobilis Esterase (PmEst.

    Directory of Open Access Journals (Sweden)

    Jose L S Lopes

    Full Text Available Enzymes isolated from thermophilic organisms found in oil reservoirs can find applications in many fields, including the oleochemical, pharmaceutical, bioenergy, and food/dairy industries. In this study, in silico identification and recombinant production of an esterase from the extremophile bacteria Petrotoga mobilis (designated PmEst were performed. Then biochemical, bioinformatics and structural characterizations were undertaken using a combination of synchrotron radiation circular dichroism (SRCD and fluorescence spectroscopies to correlate PmEst stability and hydrolytic activity on different substrates. The enzyme presented a high Michaelis-Menten constant (KM 0.16 mM and optimum activity at ~55°C for p-nitrophenyl butyrate. The secondary structure of PmEst was preserved at acid pH, but not under alkaline conditions. PmEst was unfolded at high concentrations of urea or guanidine through apparently different mechanisms. The esterase activity of PmEst was preserved in the presence of ethanol or propanol and its melting temperature increased ~8°C in the presence of these organic solvents. PmEst is a mesophilic esterase with substrate preference towards short-to medium-length acyl chains. The SRCD data of PmEst is in agreement with the prediction of an α/β protein, which leads us to assume that it displays a typical fold of esterases from this family. The increased enzyme stability in organic solvents may enable novel applications for its use in synthetic biology. Taken together, our results demonstrate features of the PmEst enzyme that indicate it may be suitable for applications in industrial processes, particularly, when the use of polar organic solvents is required.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  4. 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

    DEFF Research Database (Denmark)

    Mardo, Karin; Visnapuu, Triinu; Vija, Heiki

    2017-01-01

    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 (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...

  5. De novo biosynthesis of biodiesel by Escherichia coli in optimized fed-batch cultivation.

    Directory of Open Access Journals (Sweden)

    Yangkai Duan

    Full Text Available 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.

  6. Ethanol fermentation of HTST extruded rye grain by bacteria and yeasts

    Energy Technology Data Exchange (ETDEWEB)

    Czarnecki, Z [Univ. of Agriculture, Poznan (Poland). Inst. of Food Technology; Nowak, J [Univ. of Agriculture, Poznan (Poland). Inst. of Food Technology

    1997-09-01

    High temperature extrusion cooking of rye was used as a pretreatment for ethanol fermentation, and yeasts and bacteria were compared for their fermentation rates. Extrusion cooking caused, on average, a 7.5% increase in ethanol yield in comparison to autoclaved samples. The best results were achieved for grain with a moisture of 21-23% which was extruded at temperatures of 160-180 C. Extrusion decreased the relative viscosity of rye grain water extracts, so it was possible to mash it without {alpha}-amylase. The efficiency of fermentation of extruded rye without Termamyl was equal to that of autoclaved and traditionally mashed rye (using {alpha}-amylase). The rate of fermentation of extruded rye grain by Zymomonas was higher during the first stage, but the final ethanol yield was similar for the bacterium and the yeast. Through both microorganisms gave good quality distillates, the concentration of compounds other than ethanol achieved from extruded rye mashes, which were fermented by Z. mobilis, was five times lower than for yeasts. (orig.)

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

    Science.gov (United States)

    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.

  8. CONTROL BASED ON NUMERICAL METHODS AND RECURSIVE BAYESIAN ESTIMATION IN A CONTINUOUS ALCOHOLIC FERMENTATION PROCESS

    Directory of Open Access Journals (Sweden)

    Olga L. Quintero

    Full Text Available Biotechnological processes represent a challenge in the control field, due to their high nonlinearity. In particular, continuous alcoholic fermentation from Zymomonas mobilis (Z.m presents a significant challenge. This bioprocess has high ethanol performance, but it exhibits an oscillatory behavior in process variables due to the influence of inhibition dynamics (rate of ethanol concentration over biomass, substrate, and product concentrations. In this work a new solution for control of biotechnological variables in the fermentation process is proposed, based on numerical methods and linear algebra. In addition, an improvement to a previously reported state estimator, based on particle filtering techniques, is used in the control loop. The feasibility estimator and its performance are demonstrated in the proposed control loop. This methodology makes it possible to develop a controller design through the use of dynamic analysis with a tested biomass estimator in Z.m and without the use of complex calculations.

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

    Science.gov (United States)

    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.

  10. Produção de levana e bioetanol utilizando cascas de banana por Zymomona mobilis

    OpenAIRE

    Ferreira, Juliana [UNESP

    2013-01-01

    Muitos países estão considerando razoável, e necessário, a curto e médio prazo, um constante investimento no estudo de formas, economicamente viáveis, de obtenção de fontes renováveis de energia, com grande destaque para a produção de etanol. O aproveitamento da matéria vegetal desperta grande interesse dos pesquisadores, cientistas e industriais, devido ao fato da mesma ser encontrada em grandes quantidades em vários tipos de resíduos. Por exemplo, só no Brasil, anualmente, tem-se uma geraçã...

  11. Etudes sur le mobilier Boulle, l'ébéniste de Louis XIV : quelques problèmes d'interfaces

    OpenAIRE

    Darque-Ceretti , Evelyne; Felder , Eric; Morini , Romain; Aucouturier , Marc; Paulin , Marc-André; Mathieu-Daudé , Agnès

    2010-01-01

    National audience; Dans le cadre d'un programme mis en place par le musée du Louvre, département des objets d'art, et le C2RMF, autour de l'étude et de la restauration des mobiliers attribués à l'atelier d'André-Charles Boulle ou à ses successeurs, il a été dégagé plusieurs problèmes concernant les marqueteries métalliques et les ornements en bronze doré. Cette communication traite en premier lieu de la compréhension de la mauvaise tenue au vieillissement des collages des pièces de marqueteri...

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

    Science.gov (United States)

    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.

  13. Problemas posturais X mobiliário: uma investigação ergonômica junto aos usuários de microcomputadores de uma escola de enfermagem Posture problems X furniture: an ergonomic investigation with the personal computer users from a nursing school

    Directory of Open Access Journals (Sweden)

    Maria Helena Versiani Maciel

    1997-12-01

    Full Text Available A utilização de microcomputadores tem se tornado imprescindível atualmente e o pessoal de enfermagem, de encontro a esse avanço tecnológico vem incorporando o em sua prática, a qual é iniciada no curso de graduação. Como usuários da seção de informática de uma escola de enfermagem passamos a observar queixas de alunos em relação a adequação dos mobiliários utilizados. Interessou-nos então, desenvolver este estudo que teve por objetivo analisar os mobiliários da, sala de informática com vistas às recomendações ergonômicas e identificar as posturas corporais adotadas pelos alunos na realização da atividade de digitação. Os procedimentos utilizados foram executados em 3 fases, observação livre do ambiente físico e mensuração dos mobiliários, observação das posturas corporais e entrevistas. Os resultados apontaram que o mobiliário utilizado é inadequado no que se refere a: bancada fixa, sem apoio para os pés, sem porta documentos; as cadeiras não são reguláveis, tem largura, do encosto fora dos padrões recomendados, não possuem braços e rodas, só tem quatro pés e tem, revestimento escorregadio e duro. Apenas em 18,6% do período observado foi adotada a postura considerada ideal para atividade de digitação, ou seja, coluna vertebral ereta,, cotovelos na altura do nível da bancada, pernas fletidas e pés apoiados. Sugere-se o planejamento de postos de trabalho para digitação a partir de dados relativos as medidas antropométricas dos usuários e da utilização de mobiliários adequados, a fim de que se possa oh ter um conjunto harmonioso entre mobiliário, ambiente e usuário proporcionando conforto e evitando problemas de saúde.The computer usage has become essential nowadays and the Nursing staff meeting this technological improvement has been assimilating it in practice, which is started in Graduation course. As users of the computer division from a Nursing School we have observed students

  14. Bacterial Levan: tecnological aspects, characteristics and production/ Levana Bacteriana: aspectos tecnológicos, características e produção

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    Crispin Humberto Garcia-Cruz

    2005-06-01

    Full Text Available Levan is an exopolysaccharide, constituted by fructose units, ? (2- 6 linked, obtained by transfructosilation reaction during microorganisms fermentation in a sucrose rich but wi thout glucose, fructose or mixtures in the culture media. Bacterial levan production is a good alternative fructose source, besides having certain functional characteristics in the human body, such as a hypocholesterolemic and an anticarcinogenic agent. In the food industry, levan can be used to fix colors and flavors, as well as thickening and stabilizing agent. In the bacterial levan production, Zymomonas mobilis has been considered the best possible alternative, since it uses as carbon source sucrose or industrial residues that contain this sugar, in different concentrations, in a mineral salts rich medium. Levan production is not only influenced by carbon source and its concentration, but also by pH, temperature and type of salts. Moreover, the oxygenation of the fermentation medium, also affect the characteristics of the molecule and the cellular growth. In this revision some important topics concerning the bacterial levan production are presented.Levana é um exopolissacarídeo, constituído por unidades de frutose, unidas através de ligações ? (2- 6, obtido pela reação de transfrutosilação durante a fermentação de microrganismos em meio rico em sacarose mas não em frutose, glucose ou misturas de ambas. Pesquisas sobre bactérias produtoras de levana vêm sendo implementadas, uma vez que a mesma é uma fonte alternativa de frutose, além de apresentar características funcionais no organismo humano, como agente hipocolesterolêmico e anticarcinogênico. Na indústria de alimentos a levana pode ser empregada como fixador de cores e sabores, bem como espessante e estabilizante de vários alimentos. Das bactérias produtoras de levana, Zymomonas mobilis tem sido a melhor alternativa, uma vez que usa como fonte de carbono a sacarose ou resíduos industriais

  15. Host and symbiont intraspecific variability: The case of Paramecium calkinsi and "Candidatus Trichorickettsia mobilis".

    Science.gov (United States)

    Sabaneyeva, E; Castelli, M; Szokoli, F; Benken, K; Lebedeva, N; Salvetti, A; Schweikert, M; Fokin, S; Petroni, G

    2018-02-01

    Newly isolated strains of the ciliate Paramecium calkinsi and their cytoplasmic bacterial endosymbionts were characterized by a multidisciplinary approach, including live observation, ultrastructural investigation, and molecular analysis. Despite morphological resemblance, the characterized P. calkinsi strains showed a significant molecular divergence compared to conspecifics, possibly hinting for a cryptic speciation. The endosymbionts were clearly found to be affiliated to the species "Candidatus Trichorickettsia mobilis" (Rickettsiales, Rickettsiaceae), currently encompassing only bacteria retrieved in an obligate intracellular association with other ciliates. However, a relatively high degree of intraspecific divergence was observed as well, thus it was possible to split "Candidatus Trichorickettsia" into three subspecies, one of which represented so far only by the newly characterized endosymbionts of P. calkinsi. Other features distinguished the members of each different subspecies. In particular, the endosymbionts of P. calkinsi resided in the cytoplasm and possessed numerous peritrichous flagella, although no motility was evidenced, whereas their conspecifics in other hosts were either cytoplasmic and devoid of flagella, or macronuclear, displaying flagellar-driven motility. Moreover, contrarily to previously analyzed "Candidatus Trichorickettsia" hosts, infected P. calkinsi cells frequently became amicronucleate and demonstrated abnormal cell division, eventually leading to decline of the laboratory culture. Copyright © 2017 Elsevier GmbH. All rights reserved.

  16. Enhanced Sorbitol Production under Submerged Fermentation using Lactobacillus plantarum

    Directory of Open Access Journals (Sweden)

    Khan Nadiya Jan

    2017-04-01

    Full Text Available Background and Objective: Sorbitol is a non-toxic and slightly hygroscopic compound with different applications. Zymomonas mobiles produces sorbitol from sucrose or mixtures of glucose and fructose (formation is coupled with the dehydrogenation of glucose to glucono-δ- lactone. Recombinant Zymomonas mobilis may produce sorbitol and gluconic acid from glucose and fructose using different divalent metal ions with reduced the ethanol yield andsignificantly increased yield of sorbitol. Current study envisaged to alter the media components, physical process parameters and supplementation of amino acids for enhanced sorbitol production.Material and Methods: Several process variables were evaluated on sorbitol production including carbon sources (glucose, fructose, maltose, sucrose, carbon concentrations (5, 10, 20 and 25 g l-1, nitrogen sources (peptone, tryptone, yeast extract, beef extract and organic nitrogen mix, temperatures (25, 29, 33, 37, 41°C, pH (6, 6.5, 7 , 7.5 ,8, agitation rate (50, 100, 150, 200 rpm and amino acids (cysteine, cystine, tryptophanin batch cultivation ofLactobacillus plantarum NCIM 2912. Shake flask cultivation performed under optimum conditions like temperature 37°C, pH 7.0 and agitation rate of 150 rpm, resulted in enhanced sorbitol production. Comparative study of sorbitol production in solid state fermentation and submerged fermentation was also evaluated.Results and Conclusion: Batch cultivation under submerged conditions further performed in 7.5-l lab scale bioreactor (working volume 3.0-l under optimized conditions resulted in maximum cell biomass of 8.95±0.03 g g-1 and a sorbitol content of 9.78±0.04 g l-1 after 42.0 h of fermentation. Scale up study on bioreactor resulted in maximum sorbitol yield (Yp/x and productivity of 1.11 g g-1 and 0.50 g l-1 h under submerged fermentation, respectively.Conflict of interest: The authors declare no conflict of interest.

  17. Investigation of potential of agro-industrial residues for ethanol production by using Candida tropicalis and Zymomonas mobilis

    Science.gov (United States)

    Patle, Sonali

    India is becoming more susceptible regarding energy security with increasing world prices of crude oil and increasing dependence on imports. Based on experiments by the Indian Institute of Petroleum, a 10% ethanol blend with gasoline is being considered for use in vehicles in at least one state and it will be mandatory for all oil companies to blend petrol with 10% ethanol from October 2008. In view of the above, the Government has already started supply of 5% ethanol blended petrol from 2003 in nine states and four contiguous Union Territories. Currently, fuel ethanol is produced mainly from molasses, corn, wheat and sugar beets. The production cost of ethanol from these agro-feedstocks is more than twice the price of gasoline. The high feedstock cost poses a major obstacle to large scale implementation of ethanol as a transportation fuel. Molasses could be in short supply due to the implementation of 10% blending norm. A reduction in import duty for industrial alcohol from7.5% to 5% has been suggested. The use of lignocellulosic energy crops, and particularly low cost biomass residues, offers excellent perspectives for application of ethanol in transportation fuels (Ridder, 2000). These materials will increase the ethanol production capacity and reduce the production cost to a competitive level. There is a huge demand (500 million litres) of ethanol to meet the 5% blending in India. With the present infrastructure, only 90 million litres of ethanol was produced till November 2006 and could reach up to 140 million litres (around) till October 2007. Bioethanol from these materials provides a highly cost effective option for CO2 emission reduction in the transportation sector. The aim of the present investigation was to evaluate the potential of biomass as feedstock for ethanol production. The dedicated energy crops would require thorough support as well as planning efforts such as assessing resources, availability and utilization. Furthermore, applied research is needed to develop environmentally and socially acceptable low-cost, high quality crops and cropping systems for producing sufficient quantities of value added biomass feedstock on substantially larger areas. This would require taking a look at environmental implications and economic assessments as over 70% of Indian population directly or indirectly depends on agricultural income sources. In other words, a long term strategy of intensive research would be required to get the desired level of acceptance both by the researchers and the farmers. This would mean long term field trials with the newly developed energy crops, awareness creation, and demonstration of visual benefits to farmers leading to change in mind-set towards greater flexibility for cropping patterns. This holds enormous promising research and development opportunities, but substantially longer period might be required to achieve these goals. The petroleum industry is now committed to the use of ethanol as fuel, as it is expected to benefit sugarcane farmers as well as the oil industry in the long run. Production of ethanol from agricultural and biodegradable wastes provides a viable solution to multiple environmental problems simultaneously creating a sink for waste and renewable energy production as well. Using ethanol-blended fuels for automobiles can significantly reduce petroleum use. Ethanol is one of the best tools to fight vehicular pollution, contains more oxygen that helps complete combustion of fuel and thus reduces harmful tailpipe emissions. It also reduces particulate emissions that pose a health hazard. Currently, fuel grade ethanol is produced from sugarcane, corn, wheat and sugar beets but the ethanol production cost from these substrates is very high as compared to gasoline. This high feedstock cost is the biggest hindrance in large scale implementation of ethanol as a transportation fuel. To counter the high feedstock costs, use of lignocellulosic materials, such as crop residues, grasses, sawdust, wood chips etc., can be promoted, which presents an inexpensive and abundant renewable source for ethanol production. Also there is an enormous production of fruits and vegetables in India and a very huge amount goes waste due to post-harvest losses and a large quantity of unused portion is also generated from processing industries. These substrates can be used as a potential source for ethanol production. These substrates are complex and are required to be broken down into simple sugars by acid, alkaline or enzymatic treatment. Two common methods for converting complex substrates to fermentable sugars are dilute acid hydrolysis and concentrated acid hydrolysis, both of which use either HCl or H2 So4. Since, acid hydrolysis has few disadvantages enzymatic hydrolysis was explored and found to be a better and more economic option. After substrate selection and its hydrolysis, it is very important to optimize the fermentation parameters and scale up the process. Different agro-industrial substrates were explored for this process. (Abstract shortened by UMI.)

  18. Les patrimoines mobiliers scientifique et technique : spécificités de leur restauration, de leur conservation et de leur valorisation

    Directory of Open Access Journals (Sweden)

    Philippe Tomsin

    2007-10-01

    Full Text Available Le patrimoine mobilier scientifique et technique, de par ses matériaux et les pathologies particulières qu'il connaît, pose des problèmes spécifiques en matière de conservation et de restauration. L'auteur inventorie les aspects de cette problématique, y compris la question cruciale des lieux de conservation et de valorisation de ce patrimoine particulier. Il propose à la réflexion quelques règles déontologiques.The scientific and technical movable heritage, because of its materials and special pathologies, gives some specific problems of conservation and restoration. The author inventories the aspects of these problems, including the crucial question of the places of conservation and valorisation of this particular heritage. He proposes a thought about some deontological rules.

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

    Science.gov (United States)

    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.

  20. Monitoring microbial growth and activity using spectral induced polarization and low-field nuclear magnetic resonance

    Science.gov (United States)

    Zhang, Chi; Keating, Kristina; Revil, Andre

    2015-04-01

    Microbes and microbial activities in the Earth's subsurface play a significant role in shaping subsurface environments and are involved in environmental applications such as remediation of contaminants in groundwater and oil fields biodegradation. Stimulated microbial growth in such applications could cause wide variety of changes of physical/chemical properties in the subsurface. It is critical to monitor and determine the fate and transportation of microorganisms in the subsurface during such applications. Recent geophysical studies demonstrate the potential of two innovative techniques, spectral induced polarization (SIP) and low-field nuclear magnetic resonance (NMR), for monitoring microbial growth and activities in porous media. The SIP measures complex dielectric properties of porous media at low frequencies of exciting electric field, and NMR studies the porous structure of geologic media and characterizes fluids subsurface. In this laboratory study, we examined both SIP and NMR responses from bacterial growth suspension as well as suspension mixed with silica sands. We focus on the direct contribution of microbes to the SIP and NMR signals in the absence of biofilm formation or biomineralization. We used Zymomonas mobilis and Shewanella oneidensis (MR-1) for SIP and NMR measurements, respectively. The SIP measurements were collected over the frequency range of 0.1 - 1 kHz on Z. mobilis growth suspension and suspension saturated sands at different cell densities. SIP data show two distinct peaks in imaginary conductivity spectra, and both imaginary and real conductivities increased as microbial density increased. NMR data were collected using both CPMG pulse sequence and D-T2 mapping to determine the T2-distribution and diffusion properties on S. oneidensis suspension, pellets (live and dead), and suspension mixed with silica sands. NMR data show a decrease in the T2-distribution in S. oneidensis suspension saturated sands as microbial density increase. A

  1. Systematic simulation of a tubular recycle reactor on the basis of pilot plant experiments

    Energy Technology Data Exchange (ETDEWEB)

    Paar, H; Narodoslawsky, M; Moser, A [Technische Univ., Graz (Austria). Inst. fuer Biotechnologie, Mikrobiologie und Abfalltechnologie

    1990-10-10

    Systematic simulatiom may decisively help in development and optimization of bioprocesses. By applying simulation techniques, optimal use can be made of experimental data, decreasing development costs and increasing the accuracy in predicting the behavior of an industrial scale plant. The procedure of the dialogue between simulation and experimental efforts will be exemplified in a case study. Alcoholic fermentation of glucose by zymomonas mobilis bacteria in a gasified turbular recycle reactor was studied first by systematic simulation, using a computer model based solely on literature data. On the base of the results of this simulation, a 0.013 m{sup 3} pilot plant reactor was constructed. The pilot plant experiments, too, were based on the results of the systematic simulation. Simulated and experimental data were well in agreement. The pilot plant experiments reiterated the trends and limits of the process as shown by the simulation results. Data from the pilot plant runs were then used to improve the simulation model. This improved model was subsequently used to simulate the performances of an industrial scale plant. The results of this simulation are presented. They show that the alcohol fermentation in a tubular recycle reactor is potentially advantageous to other reactor configurations, especially to continuous stirred tanks. (orig.).

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

    Science.gov (United States)

    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.

  3. Pengaruh Variasi Mikroorganisme dan Pelarut Dalam Produksi Etanol Dari Nira Tebu (Sachharum officinarum Dengan Proses Fermentasi Ekstraktif

    Directory of Open Access Journals (Sweden)

    Yusfa Anugrah Baihaki

    2014-09-01

    Full Text Available Kebutuhan energi dari bahan bakar minyak bumi (BBM didunia semakin tahun mengalami peningkatan tajam. Salah satu energi alternatif yang didorong pemerintah Indonesia adalah dengan memproduksi bioetanol. Salah satu bahan yang sangat berpotensial sebagai bahan baku utama dalam pembuatan bioetanol adalah nira batang tebu. Upaya peningkatan produktivitas etanol dilakukan secara kontinyu dikarenakan pada fermentasi konvensional terdapat kendala pada produktivitas dan konsentrasi etanol yang rendah. Untuk itu perlu dilakukan penelitian untuk produksi etanol dengan keunggulan keterpaduan proses dan rendah energi yang selanjutnya dapat dijadikan sebagai dasar desain untuk rancang bangun skala industri kecil. Tujuan dari penelitian ini adalah untuk mengetahui performa terbaik dari variasi mikroorganisme dan pelarut yang digunakan dalam memproduksi etanol dengan proses fermentasi ekstraktif dan untuk mengetahui karakteristik kinerja sistem fermentasi kontinyu dalam bioreaktor packed bed dengan variasi mikroorganisme. Dalam penelitian ini digunakan macam variasi mikroorganisme Zymomonasmobilis A3 termutasi dan campuran Saccharomyces cerevisiae dan Pichiastipitis dengan sistem tanpa recycle dan pelarut n-Amyl Alcohol. Dari penelitian yang telah dilakukan diperoleh kesimpulan bahwa proses fermentasi kontinyu dan ekstraksi tanpa recycle menggunakan Zymomonas mobilis A3 dan pelarut n-Amyl Alkohol memberikan hasil produktivitas dan yield yang terbaik, yaitu sebesar 133,417 g/l.jam dan 35,049%.

  4. Simultaneous saccharification and co-fermentation of peracetic acid pretreated sugar cane bagasse

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, L.C. [Fundacao Centro Tecnologico de Minas Gerais, Belo Horizonte (Brazil); Linden, J.C.; Schroeder, H.A. [Colorado State University, Fort Collins, CO (United States)

    1999-07-01

    Previous work in our laboratory has demonstrated that peracetic acid improves the enzymatic digestibility of lignocellulosic materials. From the same studies, use of dilute alkali solutions as a pre-pretreatment prior to peracetic acid lignin oxidation increases sugar conversion yields in a synergistic, not additive, manner. Deacetylation of xylan is conducted easily by use of dilute alkali solutions at mild conditions. In this paper, the effectiveness of peracetic acid pretreatment of sugar cane bagasse combined with an alkaline pre-pretreatment, is evaluated through simultaneous saccharification and co-fermentation (SSCF) procedures. A practical 92% of theoretical ethanol yield using recombinant Zymomonas mobilis CP4/pZB5 is achieved using 6% NaOH/I5% peracetic acid pretreated substrate. No sugar accumulation is observed during SSCF; the recombinant microorganism exhibits greater glucose utilization rates than those of xylose. Acetate levels at the end of the co-fermentations are less than 0.2% (w/v). Based on demonstrated reduction of acetyl groups of the biomass, alkaline pre-pretreatments help to reduce peracetic acid requirements. The influence of deacetylation is more pronounced in combined pretreatments using lower peracetic acid loadings. Stereochemical impediments of the acetyl groups in hemicellulase on the activity of specific enzymes may be involved. (author)

  5. Les objets mobiliers des XIXe et XXe siècles : les sources

    Directory of Open Access Journals (Sweden)

    Laurence de Finance

    2009-11-01

    Full Text Available L’étude scientifique de tout objet ne peut se concevoir sans une recherche dans les sources documentaires. Qu’il s’agisse d’archives publiques ou privées, de legs faits à des musées ou autres institutions patrimoniales, la quête de renseignements est une nécessité pour suivre l’objet étudié depuis sa création jusqu’à son étude faite in Situ. De nos jours, de nombreuses ressources sont mises en ligne, notamment sur le site du ministère de la culture et de la communication ; accessibles à tous, elles rendent plus aisées la localisation des sources et la consultation de leur contenu. A titre d’exemple, afin de faciliter l’étude du mobilier religieux du XIXe siècle, dont la production est alors en pleine expansion, des pages illustrées de plusieurs catalogues de fabricants sont aujourd’hui consultables en ligne.The scientific study of any object requires research in documentary sources. Whether these are private or public archives, legacies left to museums or other heritage institutions, the search for information is a necessity for understanding the life of the object, from its creation to its study in situ. Today, many types of documentary source are available on line, in particular on the website of the French Ministry of Culture. These sources are available to all and easy to consult. The example presented here, concerning the study of religious furnishings of the 19th and 20th centuries, the production of which increased considerably during these centuries, are the pages taken from the catalogues of several manufacturers of these church furnishings, today accessible on line.

  6. AutoCAD 3D pour l'architecture et le design : conception d'une maison et de son mobilier

    CERN Document Server

    Riccio, Michel

    2010-01-01

    Module 3D d'AutoCAD, logiciel leader de dessin assisté par ordinateur, AutoCAD 3D est l'outil indispensable des architectes qui souhaitent présenter leurs travaux en trois dimensions. Voici donc un livre très pédagogique qui leur fera découvrir ses principales fonctionnalités (versions 2006 à 2010) à travers un projet de conception de maison contemporaine. Riche de 700 plans, schémas et dessins, il explique quels outils employer pour modéliser les façades d'une villa, sa piscine et sa terrasse, ainsi que son architecture intérieure et son mobilier. Dès les premières pages, le lecteur se retrouve ainsi plongé dans la pratique, voyant se construire au fil des 17 ateliers un édifice tridimensionnel complexe, qu'il aura la satisfaction d'avoir créé lui-même. A qui s'adresse ce livre ? Aux bureaux d'architectes qui souhaitent présenter leurs projets en 3D ; À tous les étudiants en écoles d'architecture ; Aux utilisateurs 2D d'AutoCAD qui désirent connaître les fonctions 3D de ce logiciel.

  7. Investigation of specificity determinants in bacterial tRNA-guanine transglycosylase reveals queuine, the substrate of its eucaryotic counterpart, as inhibitor.

    Directory of Open Access Journals (Sweden)

    Inna Biela

    Full Text Available Bacterial tRNA-guanine transglycosylase (Tgt catalyses the exchange of the genetically encoded guanine at the wobble position of tRNAs(His,Tyr,Asp,Asn by the premodified base preQ1, which is further converted to queuine at the tRNA level. As eucaryotes are not able to synthesise queuine de novo but acquire it through their diet, eucaryotic Tgt directly inserts the hypermodified base into the wobble position of the tRNAs mentioned above. Bacterial Tgt is required for the efficient pathogenicity of Shigella sp, the causative agent of bacillary dysentery and, hence, it constitutes a putative target for the rational design of anti-Shigellosis compounds. Since mammalian Tgt is known to be indirectly essential to the conversion of phenylalanine to tyrosine, it is necessary to create substances which only inhibit bacterial but not eucaryotic Tgt. Therefore, it seems of utmost importance to study selectivity-determining features within both types of proteins. Homology models of Caenorhabditis elegans Tgt and human Tgt suggest that the replacement of Cys158 and Val233 in bacterial Tgt (Zymomonas mobilis Tgt numbering by valine and accordingly glycine in eucaryotic Tgt largely accounts for the different substrate specificities. In the present study we have created mutated variants of Z. mobilis Tgt in order to investigate the impact of a Cys158Val and a Val233Gly exchange on catalytic activity and substrate specificity. Using enzyme kinetics and X-ray crystallography, we gained evidence that the Cys158Val mutation reduces the affinity to preQ1 while leaving the affinity to guanine unaffected. The Val233Gly exchange leads to an enlarged substrate binding pocket, that is necessary to accommodate queuine in a conformation compatible with the intermediately covalently bound tRNA molecule. Contrary to our expectations, we found that a priori queuine is recognised by the binding pocket of bacterial Tgt without, however, being used as a substrate.

  8. Clostridium thermocellum ATCC27405 transcriptomic, metabolomic and proteomic profiles after ethanol stress

    Directory of Open Access Journals (Sweden)

    Yang Shihui

    2012-07-01

    Full Text Available Abstract Background Clostridium thermocellum is a candidate consolidated bioprocessing biocatalyst, which is a microorganism that expresses enzymes for both cellulose hydrolysis and its fermentation to produce fuels such as lignocellulosic ethanol. However, C. thermocellum is relatively sensitive to ethanol compared to ethanologenic microorganisms such as yeast and Zymomonas mobilis that are used in industrial fermentations but do not possess native enzymes for industrial cellulose hydrolysis. Results In this study, C. thermocellum was grown to mid-exponential phase and then treated with ethanol to a final concentration of 3.9 g/L to investigate its physiological and regulatory responses to ethanol stress. Samples were taken pre-shock and 2, 12, 30, 60, 120, and 240 min post-shock, and from untreated control fermentations for systems biology analyses. Cell growth was arrested by ethanol supplementation with intracellular accumulation of carbon sources such as cellobiose, and sugar phosphates, including fructose-6-phosphate and glucose-6-phosphate. The largest response of C. thermocellum to ethanol shock treatment was in genes and proteins related to nitrogen uptake and metabolism, which is likely important for redirecting the cells physiology to overcome inhibition and allow growth to resume. Conclusion This study suggests possible avenues for metabolic engineering and provides comprehensive, integrated systems biology datasets that will be useful for future metabolic modeling and strain development endeavors.

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

    Science.gov (United States)

    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].

  10. Bacterial community structure of a full-scale biofilter treating pig house exhaust air

    DEFF Research Database (Denmark)

    Kristiansen, Anja; Pedersen, Kristina Hadulla; Nielsen, Per Halkjær

    2011-01-01

    Biological air filters represent a promising tool for treating emissions of ammonia and odor from pig facilities. Quantitative fluorescence in situ hybridization (FISH) and 16S rRNA gene sequencing were used to investigate the bacterial community structure and diversity in a full-scale biofilter ...... consisting of two consecutive compartments (front and back filter). The analysis revealed a highly specialized bacterial community of limited diversity, dominated by a few groups of Betaproteobacteria (especially Comamonas) and diverse Bacteroidetes. Actinobacteria, Gammaproteobacteria......, and betaproteobacterial ammoniaoxidizers (Nitrosomonas eutropha/Nitrosococcus mobilis-lineage) were also quantitatively important. Only a few quantitative differences existed between the two filter compartments at the group level, with a lower relative abundance of Actinobacteria and a higher relative abundance...

  11. Spatial separation of photosynthesis and ethanol production by cell type-specific metabolic engineering of filamentous cyanobacteria.

    Science.gov (United States)

    Ehira, Shigeki; Takeuchi, Takuto; Higo, Akiyoshi

    2018-02-01

    Cyanobacteria, which perform oxygenic photosynthesis, have drawn attention as hosts for the direct production of biofuels and commodity chemicals from CO 2 and H 2 O using light energy. Although cyanobacteria capable of producing diverse chemicals have been generated by metabolic engineering, anaerobic non-photosynthetic culture conditions are often necessary for their production. In this study, we conducted cell type-specific metabolic engineering of the filamentous cyanobacterium Anabaena sp. PCC 7120, which forms a terminally differentiated cell called a heterocyst with a semi-regular spacing of 10-15 cells. Because heterocysts are specialized cells for nitrogen fixation, the intracellular oxygen level of heterocysts is maintained very low even when adjacent cells perform oxygenic photosynthesis. Pyruvate decarboxylase of Zymomonas mobilis and alcohol dehydrogenase of Synechocystis sp. PCC 6803 were exclusively expressed in heterocysts. Ethanol production was concomitant with nitrogen fixation in genetically engineered Anabaena sp. PCC 7120. Engineering of carbon metabolism in heterocysts improved ethanol production, and strain ET14, with an extra copy of the invB gene expressed from a heterocyst-specific promoter, produced 130.9 mg L -1 of ethanol after 9 days. ET14 produced 1681.9 mg L -1 of ethanol by increasing the CO 2 supply. Ethanol production per heterocyst cell was approximately threefold higher than that per cell of unicellular cyanobacterium. This study demonstrates the potential of heterocysts for anaerobic production of biofuels and commodity chemicals under oxygenic photosynthetic conditions.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  14. The Enzymatic Conversion of Major Algal and Cyanobacterial Carbohydrates to Bioethanol

    International Nuclear Information System (INIS)

    Al Abdallah, Qusai; Nixon, B. Tracy; Fortwendel, Jarrod R.

    2016-01-01

    The production of fuels from biomass is categorized as first-, second-, or third-generation depending upon the source of raw materials, either food crops, lignocellulosic material, or algal biomass, respectively. Thus far, the emphasis has been on using food crops creating several environmental problems. To overcome these problems, there is a shift toward bioenergy production from non-food sources. Algae, which store high amounts of carbohydrates, are a potential producer of raw materials for sustainable production of bioethanol. Algae store their carbohydrates in the form of food storage sugars and structural material. In general, algal food storage polysaccharides are composed of glucose subunits; however, they vary in the glycosidic bond that links the glucose molecules. In starch-type polysaccharides (starch, floridean starch, and glycogen), the glucose subunits are linked together by α-(1→4) and α-(1→6) glycosidic bonds. Laminarin-type polysaccharides (laminarin, chrysolaminarin, and paramylon) are made of glucose subunits that are linked together by β-(1→3) and β-(1→6) glycosidic bonds. In contrast to food storage polysaccharides, structural polysaccharides vary in composition and glycosidic bond. The industrial production of bioethanol from algae requires efficient hydrolysis and fermentation of different algal sugars. However, the hydrolysis of algal polysaccharides employs more enzymatic mixes in comparison to terrestrial plants. Similarly, algal fermentable sugars display more diversity than plants, and therefore more metabolic pathways are required to produce ethanol from these sugars. In general, the fermentation of glucose, galactose, and glucose isomers is carried out by wild-type strains of Saccharomyces cerevisiae and Zymomonas mobilis. In these strains, glucose enters glycolysis, where is it converted to pyruvate through either Embden–Meyerhof–Parnas pathway or Entner–Doudoroff pathway. Other monosaccharides must be converted to

  15. The enzymatic conversion of major algal and cyanobacterial carbohydrates to bioethanol

    Directory of Open Access Journals (Sweden)

    Qusai Al Abdallah

    2016-11-01

    Full Text Available The production of fuels from biomass is categorized as first-, second- or third-generation depending upon the source of raw materials, either food crops, lignocellulosic material, or algal biomass, respectively. Thus far, the emphasis has been on using food crops creating several environmental problems. To overcome these problems, there is a shift toward bioenergy production from non-food sources. Algae, which store high amounts of carbohydrates, are a potential producer of raw materials for sustainable production of bioethanol. Algae store their carbohydrates in the form of food storage sugars and structural material. In general, algal food storage polysaccharides are composed of glucose subunits, however they vary in the glycosidic bond that links the glucose molecules. In starch-type polysaccharides (starch, floridean starch, and glycogen, the glucose subunits are linked together by α-(1→4 and α-(1→6 glycosidic bonds. Laminarin-type polysaccharides (laminarin, chrysolaminarin, and paramylon are made of glucose subunits that are linked together by β-(1→3 and β-(1→6 glycosidic bonds. In contrast to food storage polysaccharides, structural polysaccharides vary in composition and glycosidic bond. The industrial production of bioethanol from algae requires efficient hydrolysis and fermentation of different algal sugars. However, the hydrolysis of algal polysaccharides employs more enzymatic mixes in comparison to terrestrial plants. Similarly, algal fermentable sugars display more diversity than plants, and therefore more metabolic pathways are required to produce ethanol from these sugars. In general, the fermentation of glucose, galactose, and glucose isomers is carried out by wild type strains of Saccharomyces cerevisiae and Zymomonas mobilis. In these strains, glucose enters glycolysis, where is it converted to pyruvate through either Embden-Meyerhof-Parnas pathway or Entner-Doudoroff pathway. Other monosaccharides must be

  16. The Enzymatic Conversion of Major Algal and Cyanobacterial Carbohydrates to Bioethanol

    Energy Technology Data Exchange (ETDEWEB)

    Al Abdallah, Qusai, E-mail: qalabdal@uthsc.edu [Department of Clinical Pharmacy, University of Tennessee Health Science Center, Memphis, TN (United States); Nixon, B. Tracy [Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA (United States); Fortwendel, Jarrod R. [Department of Clinical Pharmacy, University of Tennessee Health Science Center, Memphis, TN (United States)

    2016-11-04

    The production of fuels from biomass is categorized as first-, second-, or third-generation depending upon the source of raw materials, either food crops, lignocellulosic material, or algal biomass, respectively. Thus far, the emphasis has been on using food crops creating several environmental problems. To overcome these problems, there is a shift toward bioenergy production from non-food sources. Algae, which store high amounts of carbohydrates, are a potential producer of raw materials for sustainable production of bioethanol. Algae store their carbohydrates in the form of food storage sugars and structural material. In general, algal food storage polysaccharides are composed of glucose subunits; however, they vary in the glycosidic bond that links the glucose molecules. In starch-type polysaccharides (starch, floridean starch, and glycogen), the glucose subunits are linked together by α-(1→4) and α-(1→6) glycosidic bonds. Laminarin-type polysaccharides (laminarin, chrysolaminarin, and paramylon) are made of glucose subunits that are linked together by β-(1→3) and β-(1→6) glycosidic bonds. In contrast to food storage polysaccharides, structural polysaccharides vary in composition and glycosidic bond. The industrial production of bioethanol from algae requires efficient hydrolysis and fermentation of different algal sugars. However, the hydrolysis of algal polysaccharides employs more enzymatic mixes in comparison to terrestrial plants. Similarly, algal fermentable sugars display more diversity than plants, and therefore more metabolic pathways are required to produce ethanol from these sugars. In general, the fermentation of glucose, galactose, and glucose isomers is carried out by wild-type strains of Saccharomyces cerevisiae and Zymomonas mobilis. In these strains, glucose enters glycolysis, where is it converted to pyruvate through either Embden–Meyerhof–Parnas pathway or Entner–Doudoroff pathway. Other monosaccharides must be converted to

  17. Differential antibiotic sensitivity determined by the large ribosomal subunit in thermophilic archaea.

    OpenAIRE

    Ruggero, D; Londei, P

    1996-01-01

    Hybrid ribosomes obtained by mixing the ribosomal subunits of the extremely thermophilic archaea Sulfolobus solfataricus and Desulfurococcus mobilis were tested for their sensitivity to selected antibiotics. It is shown that structural differences in the large ribosomal subunits determine qualitatively and quantitatively the patterns of response to alpha-sarcin and paromomycin in these species.

  18. NCBI nr-aa BLAST: CBRC-FCAT-01-1240 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-FCAT-01-1240 ref|ZP_01126060.1| DNA internalization-related competence protein... ComEC/Rec2 [Nitrococcus mobilis Nb-231] gb|EAR23543.1| DNA internalization-related competence protein ComEC/Rec2 [Nitrococcus mobilis Nb-231] ZP_01126060.1 3.6 31% ...

  19. Technical development of fuel alcohol

    Energy Technology Data Exchange (ETDEWEB)

    1988-06-01

    Research and development of a technology for biologically manufacturing alcohol from agricultural and forestry wastes has been conducted according to an eight year-program beginning in 1983. This paper presents the findings in FY 1987 and the future schedule. Exploration and breeding of superior bacteria are the basic subject through the eight years. In FY 1987, preparation and evaluation of hybrid plasmids into which Zymomonas, BETA-glucosidase gene and CM case gene are inserted, improvement of variation to enhance the salt resistance of Zymomonas and screening of Cm-and Sm-resistant bacteria to develop thermophilic, anaerobic cellulose were made. In addition, the total process combining the cell adhesion method as the immobilization technique with the flash technique is continuously studied. Improvement of the salt-resistance of Zymomonas by increasing the density with photosetting resin, the upper concentration of alcohol and effect of pulverzing treatment in a small apparatus were investigated. A test plant was designed and constructed. (3 photos.)

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

    Science.gov (United States)

    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.

  1. Metabolic regulation analysis of an ethanologenic Escherichia coli strain based on RT-PCR and enzymatic activities

    Directory of Open Access Journals (Sweden)

    Martinez Alfredo

    2008-05-01

    Full Text Available Abstract Background A metabolic regulation study was performed, based upon measurements of enzymatic activities, fermentation performance, and RT-PCR analysis of pathways related to central carbon metabolism, in an ethanologenic Escherichia coli strain (CCE14 derived from lineage C. In comparison with previous engineered strains, this E coli derivative has a higher ethanol production rate in mineral medium, as a result of the elevated heterologous expression of the chromosomally integrated genes encoding PDCZm and ADHZm (pyruvate decarboxylase and alcohol dehydrogenase from Zymomonas mobilis. It is suggested that this behavior might be due to lineage differences between E. coli W and C. Results This study demonstrated that the glycolytic flux is controlled, in this case, by reactions outside glycolysis, i.e., the fermentative pathways. Changes in ethanol production rate in this ethanologenic strain result in low organic acid production rates, and high glycolytic and ethanologenic fluxes, that correlate with enhanced transcription and enzymatic activity levels of PDCZm and ADHZm. Furthermore, a higher ethanol yield (90% of the theoretical in glucose-mineral media was obtained with CCE14 in comparison with previous engineered E. coli strains, such as KO11, that produces a 70% yield under the same conditions. Conclusion Results suggest that a higher ethanol formation rate, caused by ahigher PDCZm and ADHZm activities induces a metabolic state that cells compensate through enhanced glucose transport, ATP synthesis, and NAD-NADH+H turnover rates. These results show that glycolytic enzymatic activities, present in E. coli W and C under fermentative conditions, are sufficient to contend with increases in glucose consumption and product formation rates.

  2. Ethanol production from lignocellulosic materials. Fermentation and on-line analysis

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, L.

    1994-04-01

    The fermentation performance of bacteria, yeast and fungi was investigated in lignocellulosic hydrolysates with the aim of finding microorganisms which both withstand the inhibitors and that have the ability to ferment pentoses. Firstly, the performance of Saccharomyces cidri, Saccharomyces cerevisiae, Lactobacillus brevis, Lactococcus lactis ssp lactis, Escherichia coli and Zymomonas mobilis was investigated in spent sulphite liquor and enzymatic hydrolysate of steam-pretreated willow. Secondly, the performance of natural and recombinant E. coli, Pichia stipitis, recombinant S. cerevisiae, S. cerevisiae in combination with xylose isomerase and Fusarium oxysporum was investigated in a xylose-rich acid hydrolysate of corn cob. Recombinant E. coli was the best alternative for fermentation of lignocellulosic hydrolysates, giving both high yields and productivities. The main drawback was that detoxification was necessary. The kinetics of the fermentation with recombinant E. coli KO11 was investigated in the condensate of steam-pretreated willow. A cost analysis of the ethanol production from willow was made, which predicted an ethanol production cost of 3.9 SEK/l for the pentose fermentation. The detoxification cost constituted 22% of this cost. The monitoring of three monosaccharides and ethanol in lignocellulosic hydro lysates is described. The monosaccharides were determined using immobilized pyranose oxidase in an on-line amperometric analyser. Immobilization and characterization of pyranose oxidase from Phanerochaete chrysosporium is also described. The ethanol was monitored on-line using a micro dialysis probe as an in situ sampling device. The dialysate components were then separated in a column liquid chromatographic system and the ethanol was selectively detected by an amperometric alcohol bio sensor. The determinations with on-line analysis methods agreed well with off-line methods. 248 refs, 4 figs, 12 tabs

  3. Cloning of affecting pyruvate decarboxylase gene in the production bioethanol of agricultural waste in the E.coli bacteria

    Directory of Open Access Journals (Sweden)

    Masome Zeinali

    2016-09-01

    Full Text Available Introduction: Ethanol made by a biomass is one of the useful strategies in terms of economic and environmental and as a clean and safe energy to replace fossil fuels considered and examined. Materials and methods: In this study, key enzyme in the production of ethanol (Pyruvate decarboxylase from Zymomonas mobilis bacteria was isolated and cloned at E. coli bacteria by freeze and thaw method. For gene cloning, we used specific primers of pdc and PCR reaction and then pdc gene isolated and pET 28a plasmid double digested with (Sal I and Xho I enzymes. Digestion Products were ligated by T4 DNA ligase in 16 °C for 16 hours. Results: Results of bacteria culture showed that a few colonies containing pET 28a plasmid could grow. Result of colony pcr of pdc gene with specific primers revealed 1700 bp bands in 1% agarose gel electrophoresis. The results of PCR with T7 promotor forward primer and pdc revers primer have proved the accurate direction of integration of pdc gene into plasmid and revealed 1885 bp band. Double digestion of recombinant plasmid with SalI and XhoI enzymes revealed same bands. Finally, RT showed the expected band of 1700 bp that implies the desired gene expression in the samples. Discussion and conclusion: Due to the increased production of ethanol via pyruvate decarboxylase gene cloning in expression plasmids with a strong promoter upstream of the cloning site can conclude that, pyruvate decarboxylase cloning as a key gene would be useful and according to beneficial properties of E. coli bacteria, transfering the gene to bacteria appears to be reasonable.

  4. Contabilização de títulos e valores mobiliários: uma comparação entre as normas brasileiras, do FASB e do IASB Accounting treatment of debt and equity securities: a comparison among brazilian, FASB and IASB standards

    Directory of Open Access Journals (Sweden)

    Alceu Haruo Fuji

    2008-08-01

    Full Text Available Em 2001, o Banco Central do Brasil emitiu a Circular 3.068, determinando a utilização do valor de mercado para avaliar os títulos e valores mobiliários. A Circular 3.068/01 determina que os títulos e valores mobiliários devem ser classificados numa das seguintes categorias: negociação, disponíveis para venda e mantidos até o vencimento. Os títulos para negociação e os disponíveis para venda devem ser avaliados e registrados pelo seu valor de mercado e os mantidos até o vencimento devem ser registrados pelo seu custo histórico. O objetivo deste trabalho é estudar a forma de contabilização de títulos adotada no Brasil, especialmente as normas definidas para as instituições financeiras, em comparação com as normas do FASB e IASB. A comparação da forma de contabilização de títulos adotada no Brasil (Circular 3.068/01 com os pronunciamentos do FASB (SFAS 115 e IASB (IAS 39 mostrou que, nos aspectos relevantes, as regras estão em harmonia, embora algumas diferenças pequenas tenham sido identificadas.In 2001, the Brazilian Central Bank issued Circular letter 3.068, determining the use of market value to evaluate debt and equity securities. This letter states that debt and equity securities must be classified in one of the following categories: trading, available for sale and held to maturity. The securities for trading and available for sale have to be evaluated and reported by their market value and those held to maturity must be reported by historical cost. The purpose of this work is to study the accounting methods of securities adopted in Brazil, especially those rules stated to financial institutions, in comparison with the statement of FASB and IASB. The comparison of the accounting methods of securities adopted in Brazil (Circular 3.068/01 with the statements of FASB (SFAS 115 and IASB (IAS 39 showed that, in the main aspects, the rules are in harmony, although some minor differences have been identified.

  5. From lin-Benzoguanines to lin-Benzohypoxanthines as Ligands for Zymomonas mobilis tRNA-Guanine Transglycosylase: Replacement of Protein-Ligand Hydrogen Bonding by Importing Water Clusters.

    NARCIS (Netherlands)

    Barandun, L.J.; Immekus, F.; Kohler, P.C.; Tonazzi, S.; Wagner, B.; Wendelspiess, S.; Ritschel, T.; Heine, A.; Kansy, M.; Klebe, G.; Diederich, F.

    2012-01-01

    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

  6. Bacterial biosynthesis and maturation of the didemnin anti-cancer agents

    KAUST Repository

    Xü , Ying; Kersten, Roland D.; Nam, Sang Jip; Lu, Liang; Al-Suwailem, Abdulaziz M.; Zheng, Huajun; Fenical, William H.; Dorrestein, Pieter C.; Moore, Bradley S.; Qian, Peiyuan

    2012-01-01

    The anti-neoplastic agent didemnin B from the Caribbean tunicate Trididemnum solidum was the first marine drug to be clinically tested in humans. Because of its limited supply and its complex cyclic depsipeptide structure, considerable challenges were encountered during didemnin B's development that continue to limit aplidine (dehydrodidemnin B), which is currently being evaluated in numerous clinical trials. Herein we show that the didemnins are bacterial products produced by the marine α-proteobacteria Tistrella mobilis and Tistrella bauzanensis via a unique post-assembly line maturation process. Complete genome sequence analysis of the 6,513,401 bp T. mobilis strain KA081020-065 with its five circular replicons revealed the putative didemnin biosynthetic gene cluster (did) on the 1,126,962 bp megaplasmid pTM3. The did locus encodes a 13-module hybrid non-ribosomal peptide synthetase-polyketide synthase enzyme complex organized in a collinear arrangement for the synthesis of the fatty acylglutamine ester derivatives didemnins X and Y rather than didemnin B as first anticipated. Imaging mass spectrometry of T. mobilis bacterial colonies captured the time-dependent extracellular conversion of the didemnin X and Y precursors to didemnin B, in support of an unusual post-synthetase activation mechanism. Significantly, the discovery of the didemnin biosynthetic gene cluster may provide a long-term solution to the supply problem that presently hinders this group of marine natural products and pave the way for the genetic engineering of new didemnin congeners. © 2012 American Chemical Society.

  7. Bacterial biosynthesis and maturation of the didemnin anti-cancer agents

    KAUST Repository

    Xü, Ying

    2012-05-23

    The anti-neoplastic agent didemnin B from the Caribbean tunicate Trididemnum solidum was the first marine drug to be clinically tested in humans. Because of its limited supply and its complex cyclic depsipeptide structure, considerable challenges were encountered during didemnin B\\'s development that continue to limit aplidine (dehydrodidemnin B), which is currently being evaluated in numerous clinical trials. Herein we show that the didemnins are bacterial products produced by the marine α-proteobacteria Tistrella mobilis and Tistrella bauzanensis via a unique post-assembly line maturation process. Complete genome sequence analysis of the 6,513,401 bp T. mobilis strain KA081020-065 with its five circular replicons revealed the putative didemnin biosynthetic gene cluster (did) on the 1,126,962 bp megaplasmid pTM3. The did locus encodes a 13-module hybrid non-ribosomal peptide synthetase-polyketide synthase enzyme complex organized in a collinear arrangement for the synthesis of the fatty acylglutamine ester derivatives didemnins X and Y rather than didemnin B as first anticipated. Imaging mass spectrometry of T. mobilis bacterial colonies captured the time-dependent extracellular conversion of the didemnin X and Y precursors to didemnin B, in support of an unusual post-synthetase activation mechanism. Significantly, the discovery of the didemnin biosynthetic gene cluster may provide a long-term solution to the supply problem that presently hinders this group of marine natural products and pave the way for the genetic engineering of new didemnin congeners. © 2012 American Chemical Society.

  8. Technical development of alcohol for fuel. Inspection and breeding of superior bacteria

    Energy Technology Data Exchange (ETDEWEB)

    1987-09-01

    Heat- and alcohol-resistant bacteria for alcoholic fermentation were separated from the soils in Japan and abroad and the performance was evaluated to develop superior bacteria for ethanol fermentation. The superior bacteria pertinent to alcoholic fermentation were bred by domestication, variation treatment, cell fusion and gene manipulation. The productivity of ethanol was increased by controlling pH of thermophilic, aerobic cellulase and culturing the mixture of added nutrients. CMC ase and Beta-glucosidase genes, the component enzymes of cellulase, were successfully developed by Zymomonas sp. A promotor selecting vector of Zymomonas was produced for developing xylolase gene to acquire an active promotor.

  9. Le début du ive s. av. J.-C. dans l’espace culturel sénonais : les habitats de Bois d’Echalas à Ville-Saint-Jacques et de Beauchamp à Varennes-sur-Seine (Seine-et-Marne dans le contexte de l’interfluve Seine-Yonne The beginning of the 4th century BC in the the cultural space of the 'Sénonais': the settlements of Bois d’Echalas at Ville-Saint-Jacques and Beauchamp at Varennes-sur-Seine (Seine-et-Marne in the context of the land separating the Seine and the Yonne

    Directory of Open Access Journals (Sweden)

    Jean-Marc Séguier

    2008-04-01

    Full Text Available L’étude de deux habitats du début du ive s. av. J.-C. installés à proximité de la confluence Seine-Yonne permet de définir le faciès mobilier de cette partie du Bassin parisien au cours de La Tène B1a, notamment grâce à l’association d’un important cortège de céramiques locales et importées et d’un mobilier métallique significatif. L’analyse des structures de conservation et du mobilier conduit à établir une hiérarchie des établissements. Celui de Ville-Saint-Jacques, Bois d’Echalas, occupe une place prééminente dans le système social mis en place dans la région considérée, alors que celui de Varennes-sur-Seine, Beauchamp, se révèle d’un niveau inférieur. Au-delà de la comparaison entre les deux sites, c’est une lecture socio-économique de l’organisation territoriale qui est proposée.The study of two settlements of the beginning of the 4th century BC near the confluence of the Seine and the Yonne enables us to define the movable culture of this part of the Paris basin during La Tène B1a, notably because of the association of an important series of local and imported ceramics and significant metal articles. The analysis of the structures of conservation and of furniture lead to the establishment of a hierachy of settlements. That of Ville-Saint-Jacques, Bois d’Echalas, occupied a prominent place in the social system set up in the region in question, whereas that of Varennes-sur-Seine, Beauchamp, proved to be of a lower level. Beyond the comparison between the two sites, what is presented is a socio-economic lecture on territorial organisation.

  10. New bacteria suitable for production of ethanol from maltose. Marutosu kara no etanoru seizo ni tekishita shinki saikin

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, T.; Taguchi, H.; Nakamura, K. (Kirin Brewery Co. Ltd., Tokyo (Japan))

    1992-10-07

    Bacteria such as Zymomonas atracts attention in production of ethanol from carbohydrates in addition to yeast used for a long time, however, Zymomonas ferments only glucose, fructose and sucrose. After searching microbes in the nature with excellent properties in fermentation ability and salt resistance, a new Gram-negative bacterium has been isolated from a certain tree sap which is suitable for production of ethanol from maltose and starch hydrolyzate. The features of cell morphology of the new bacterium are: bacillus, peritrichous, no sport forming, Q-9 in quinone system, and an anaerobic Gram-negative bacterium. It utilizes maltose, sorbitol and maltose and produces [alpha]-glucosidas but no [beta]-galactosidase nor arginine dihydrase. The strain T109 is deposited as FERM BP-3292 to the Industrial Research Institute of Microbiology. 2 figs., 2 tabs.

  11. A novel aldose-aldose oxidoreductase for co-production of D-xylonate and xylitol from D-xylose with Saccharomyces cerevisiae.

    Science.gov (United States)

    Wiebe, Marilyn G; Nygård, Yvonne; Oja, Merja; Andberg, Martina; Ruohonen, Laura; Koivula, Anu; Penttilä, Merja; Toivari, Mervi

    2015-11-01

    An open reading frame CC1225 from the Caulobacter crescentus CB15 genome sequence belongs to the Gfo/Idh/MocA protein family and has 47 % amino acid sequence identity with the glucose-fructose oxidoreductase from Zymomonas mobilis (Zm GFOR). We expressed the ORF CC1225 in the yeast Saccharomyces cerevisiae and used a yeast strain expressing the gene coding for Zm GFOR as a reference. Cell extracts of strains overexpressing CC1225 (renamed as Cc aaor) showed some Zm GFOR type of activity, producing D-gluconate and D-sorbitol when a mixture of D-glucose and D-fructose was used as substrate. However, the activity in Cc aaor expressing strain was >100-fold lower compared to strains expressing Zm gfor. Interestingly, C. crescentus AAOR was clearly more efficient than the Zm GFOR in converting in vitro a single sugar substrate D-xylose (10 mM) to xylitol without an added cofactor, whereas this type of activity was very low with Zm GFOR. Furthermore, when cultured in the presence of D-xylose, the S. cerevisiae strain expressing Cc aaor produced nearly equal concentrations of D-xylonate and xylitol (12.5 g D-xylonate l(-1) and 11.5 g D-xylitol l(-1) from 26 g D-xylose l(-1)), whereas the control strain and strain expressing Zm gfor produced only D-xylitol (5 g l(-1)). Deletion of the gene encoding the major aldose reductase, Gre3p, did not affect xylitol production in the strain expressing Cc aaor, but decreased xylitol production in the strain expressing Zm gfor. In addition, expression of Cc aaor together with the D-xylonolactone lactonase encoding the gene xylC from C. crescentus slightly increased the final concentration and initial volumetric production rate of both D-xylonate and D-xylitol. These results suggest that C. crescentus AAOR is a novel type of oxidoreductase able to convert the single aldose substrate D-xylose to both its oxidized and reduced product.

  12. Studies on the Catalytic Properties of Partially Purified Alkaline Proteases from Some Selected Microorganisms

    Directory of Open Access Journals (Sweden)

    Titilayo Olufunke Femi-Ola

    2012-09-01

    Full Text Available Aims: The research was done to study the conditions enhancing catalytic activities of alkaline proteases from Vibro sp., Lactobacillus brevis, Zymomonas sp., Athrobacter sp., Corynebacterium sp. and Bacillus subtilis.Methodology and Results: The proteolytic enzymes were purified in 2-step procedures involving ammonium sulphate precipitation and sephadex G-150 gel permeation chromatography. The upper and lower limits for the specific activities of proteases from the selected microorganisms were estimated at 20.63 and 47.51 units/mg protein with Zymomonas protease having the highest specific activity towards casein as its substrate and purification fold of 3.46, while that ofLactobacillus brevis protease was 8.06. The native molecular weights of these active proteins ranged from 30.4 to 45.7 kDa with Athrobacter sp. protease having the highest weight for its subunits. The proteolytic enzymes had optimum pH range of 8 to 10 and temperature range of 50 to 62 ºC accounting for the percentage relative activity range of 75 to 94% and 71 to 84 % respectively. The activities of Lactobacillus brevis and Bacillus subtilis proteases were maximum at pH 9 and 10 respectively. Lactobacillus brevis protease activity was maximum at temperature of 62 ºC, while beyond this value, a general thermal instability of these active proteins was observed. At above 70 ºC, the catalytic activities of Corynebacterium sp., Vibrio sp., Zymomonas sp. and Arthrobacter sp. proteases were progressively reduced over a period of 120 min of incubation, while Bacillus subtlis and Lactobacillus brevis proteases were relatively stable. Effect of metal ions was investigated on the catalytic activity of protease from the microorganisms. Lactobacillus brevis,Zymomonas sp., Arthrobacter sp., Corynebacterium sp. and Bacillus subtilis protease activities were strongly activated by metal ions such as Ca+2 and Mg+2. Enzyme activities were inhibited strongly by Cu2+ and Hg2+ but were not

  13. The effects of salinity on nitrification using halophilic nitrifiers in a Sequencing Batch Reactor treating hypersaline wastewater.

    Science.gov (United States)

    Cui, You-Wei; Zhang, Hong-Yu; Ding, Jie-Ran; Peng, Yong-Zhen

    2016-04-25

    With annual increases in the generation and use of saline wastewater, the need to avoid environmental problems such as eutrophication is critical. A previous study identified ways to start up a halophilic sludge domesticated from estuarine sediments to remove nitrogen from wastewater with a salinity of 30 g/L. This investigation expands that work to explore the impact of salinity on nitrogen removal. This study demonstrated that the mixed halophilic consortia removed nitrogen from wastewater with a salinity of 30-85 g/L. A kinetic analysis showed that halophilic nitrifiers selected based on hypersalinity were characterized by low Ks, μmax and specific ammonium oxidization rates. This explains the decrease in ammonium removal efficiency in the high salinity operational phases. Salinity inhibited ammonia oxidizing bacteria (AOB) activity, as well as the number of dominant AOB, but did not significantly affect the AOB dominant species. Three most dominant AOB lineages in the halophilic sludge were Nitrosomonas marina, Nitrosomonas europaea, and Nitrosococcus mobilis. Nitrosomonas europaea and Nitrosococcus mobilis were mainly affected by salinity, while nitrite accumulation and ammonia loading played the key role in determining the abundance of Nitrosococcus mobilis and Nitrosococcus europaea. The study contributes insights about shifts in halophilic nitrifying bacterial populations.

  14. Ekstravagantsus vannitoas

    Index Scriptorium Estoniae

    2008-01-01

    Tutvustatakse Tallinnas Vannistuudios pakutavaid Itaalia firma Mobili Di Castello peegliga valamukomplekte, Itaalia firma Ritmonio dushiroosi Euridice ja valamusegistit Type-Face, Inglismaa firma Imperial Bathrooms dushikabiine ja malmvanni Radison Cureo

  15. ANÁLISE ERGONÔMICA DOS POSTOS DE TRABALHO DE OPERADORES DE CAIXA DE SUPERMERCADO

    Directory of Open Access Journals (Sweden)

    Lucimara Ballardin

    2005-06-01

    Full Text Available Esta pesquisa teve o objetivo avaliar as condições de trabalho e os postos de trabalho dos operadores de caixa dos principais supermercados da cidade de Santa Maria (RS.Um total de 60 operadores de caixa de 9 supermercados foram incluídos no estudo. A coleta de dados foi realizada através de questionários, mensuração do posto de trabalho (antropometria e mobiliário, observações diretas e aplicação do  check-list. Os resultados demonstraram condições de trabalho prejudiciais à saúde, como longas jornadas de trabalho e alta prevalência de desconfortos músculo-esqueléticos. A sintomatologia foi avaliada pelos trabalhadores como resultado de fatores relacionados ao trabalho, como movimentos biomecânicos de passagem e registro de mercadorias, posturas exigidas pelo posto de trabalho e mobiliário utilizado no posto de trabalho. As observações diretas analisaram as rotinas do trabalho e apontaram os movimentos realizados pelos operadores. A comparação entre medidas do mobiliário e antropometria demonstra incompatibilidade entre os componentes do posto de trabalho. A aplicação do  check-list confirmou o alto  risco de Distúrbio Osteomuscular Relacionado ao  Trabalho e a necessidade de  melhorias nas condições de trabalho desta categoria profissional.

  16. Journal of Applied Sciences and Environmental Management - Vol 9 ...

    African Journals Online (AJOL)

    Activity of Zymomonas species in palm-sap obtained from three areas in Edo State, Nigeria. ... Flood risk assessment: a review. TE Ologunorisa, MJ Abawua. A preliminary evaluation of otamiri river sands for the production of plain glass ... Health impact assessment of mangrove vegetation in an oil spilled site at the Bodo ...

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

    Science.gov (United States)

    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

  18. Mirepoix – Les Olivettes

    OpenAIRE

    Guédon, Frédéric

    2016-01-01

    Un projet de clinique vétérinaire, à l’ouest de Mirepoix, a entraîné ce diagnostic archéologique. Il ressort qu’une cuvette naturelle a été comblée par un niveau de colluvions riche en mobilier archéologique antique (de l’amphore surtout) couvrant une large période. Ce niveau scelle de rares structures en creux (une fosse et deux fossés). Le projet est donc en périphérie d’un site d’habitat, que l’on peut supposer être au sud ou à l’est de l’emprise.

  19. Le comportement symbolique dans la Préhistoire de la Roumanie: art mobilier au Paléolithique supérieur en Moldavie

    Directory of Open Access Journals (Sweden)

    Corneliu BELDIMAN

    2009-12-01

    Full Text Available RÉSUMÉ: Les approches récentes des collections anciennes aussi bien que les découvertes des derniers décennies ont permis des discussions détaillés (concernant le répertoire, la typologie, la technologie, les dates radiométriques, etc. sur les rares documents d’art mobilier (parure, objets décorés et dites “non utilitaires” appartenant au Paléolithique supérieur (Gravettien oriental, autour 23-13 kya BP et provenant de la Moldavie roumaine –région Est du pays, comprise entre les Carpates et la rivière Prut–. Les 29 artefacts signalés ont été découvertes en 6 sites de plein aire et dans un site en grotte. Les types identifiés sont: bâtons percés sur métatarse de cheval et sur bois de renne; pendeloques lithiques et en os; rondelle en bois de renne; dents percées; objets lithiques en quartzite et graphite; objets gravés et encochés lithiques et en os; harpon décoré; fragment de défense de mammouth ayant des traces de débitage et façonnage; coquilles fossiles appartenant à l’espèce Congeria?; coquilles percées appartenant à l’espèce Succinea oblonga? ou Lithoglyphus naticoides? La plupart des artéfacts ont une signification spéciale pour le phénomène de l’art et de la technologie préhistorique de la région envisagée: il s’agit des pendeloques de Mitoc, dép. de Botosani et de fragment d’os gravé d’une représentation de patte d’animal? de Piatra Neamt, dép. de Neamt. Une autre pièce exceptionnelle c’est le fragment de défense de mammouth de Lespezi, dép. de Bacau portant sur l’extrémité proximale des traces de débitage par entaillage et probablement par sciage à la ficelle; cela peut être le plus ancienne situation de cette sorte signalée dans cette partie de l’Europe. Tenant compte du fait que les objets en ivoire de mammouth sont apparitions extrêmement rares dans le Paléolithique supérieur de la Roumanie et les analogies on peut envisager la provenance de cet

  20. Gynogenetic induction in marine bivalve molluscs for improvement of stocks: Standardization of some important factors

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, U.

    Experiments conducted for standardizing sperm density for artificial insemination of Chlamys mobilis prior to inducing gynogenesis by ultra-violet rays irradiated sperms showed that 10:1 ratio of sperms to eggs should be maintained for getting...

  1. GenBank blastx search result: AK062185 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK062185 001-046-E03 AF080002.1 Heliobacillus mobilis exopolyphosphatase Ppx (ppx) gene, partial cds; cobyric acid synthase CobQ (cobQ), UDP-N-acetylmuramyl tripeptide synthetase MurC (murC),

  2. Solution-processable septithiophene monolayer transistor

    NARCIS (Netherlands)

    Defaux, M.; Gholamrezaie, F.; Wang, J.; Kreyes, A.; Ziener, U.; Anokhin, D.V.; Ivanov, D.A.; Moser, A.; Neuhold, A.; Salzmann, I.; Resel, R.; Leeuw, de D.M.; Meskers, S.C.J.; Moeller, M.; Mourran, A.

    2012-01-01

    Septithiophene with endgroups designed to form liquid crystalline phases and allows controlled deposition of an electrically connected monolayer. Field effect mobilies mobilities of charge carriers and spectroscopic properties of the monolayer provide evidence of sustainable transport and

  3. Solution-Processable Septithiophene Monolayer Transistor

    NARCIS (Netherlands)

    Defaux, Matthieu; Gholamrezaie, Fatemeh; Wang, Jingbo; Kreyes, Andreas; Ziener, Ulrich; Anokhin, Denis V.; Ivanov, Dimitri A.; Moser, Armin; Neuhold, Alfred; Salzmann, Ingo; Resel, Roland; de Leeuw, Dago M.; Meskers, Stefan C. J.; Moeller, Martin; Mourran, Ahmed

    2012-01-01

    Septithiophene with endgroups designed to form liquid crystalline phases and allows controlled deposition of an electrically connected monolayer. Field effect mobilies mobilities of charge carriers and spectroscopic properties of the monolayer provide evidence of sustainable transport and

  4. The Mobile usability in educational contexts

    Directory of Open Access Journals (Sweden)

    Agnes Kukulska-Hulme

    2008-01-01

    Full Text Available Riflessioni sul rapporto fra le tecnologie mobile e la didattica, con particolare attenzione ai risultati ottenuti da alcuni studi sperimentali sul mobile learning. Viene analizzata l’usabilita’ dei dispositivi mobili nella formazione a distanza.

  5. Evaluation of an Automated Swallow-Detection Algorithm Using Visual Biofeedback in Healthy Adults and Head and Neck Cancer Survivors.

    Science.gov (United States)

    Constantinescu, Gabriela; Kuffel, Kristina; Aalto, Daniel; Hodgetts, William; Rieger, Jana

    2017-11-02

    Mobile health (mHealth) technologies may offer an opportunity to address longstanding clinical challenges, such as access and adherence to swallowing therapy. Mobili-T ® is an mHealth device that uses surface electromyography (sEMG) to provide biofeedback on submental muscles activity during exercise. An automated swallow-detection algorithm was developed for Mobili-T ® . This study evaluated the performance of the swallow-detection algorithm. Ten healthy participants and 10 head and neck cancer (HNC) patients were fitted with the device. Signal was acquired during regular, effortful, and Mendelsohn maneuver saliva swallows, as well as lip presses, tongue, and head movements. Signals of interest were tagged during data acquisition and used to evaluate algorithm performance. Sensitivity and positive predictive values (PPV) were calculated for each participant. Saliva swallows were compared between HNC and controls in the four sEMG-based parameters used in the algorithm: duration, peak amplitude ratio, median frequency, and 15th percentile of the power spectrum density. In healthy participants, sensitivity and PPV were 92.3 and 83.9%, respectively. In HNC patients, sensitivity was 92.7% and PPV was 72.2%. In saliva swallows, HNC patients had longer event durations (U = 1925.5, p performed well with healthy participants and retained a high sensitivity, but had lowered PPV with HNC patients. With respect to Mobili-T ® , the algorithm will next be evaluated using the mHealth system.

  6. Report on a survey in fiscal 1999. Survey on industrial utilization of microorganism reaction mechanisms under anaerobic condition; 1999 nendo kenki jokenka ni okeru biseibutsu hanno kiko no kogyoteki riyo ni kansuru chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Industrial utilization of reaction mechanisms of microorganisms under anaerobic condition permits structuring energy saving type production processes. The present survey has investigated features of new microorganisms under anaerobic condition and the status of researches thereon inside and outside the country, and discussed their future applications. Chapter 1 compares anaerobic microorganisms and functions of microorganism under anaerobic condition with those aerobic to describe their general features, and describes the purpose of this survey and the summary of the investigations. Chapter 2 surveys the current status of technologies to utilize microorganisms under anaerobic condition. Chapter 3 outlines metabolic characteristics of the anaerobic microorganisms, and extracts functions effective for material production by different anaerobic microorganisms to describe their applicability. Chapter 4 evaluates the system classification for the anaerobic microorganisms utilizing the basic arrangement of 16S rRNA genes, and extracts technical problems therein. Chapter 5 proposes structuring a total methane fermentation system including a raw material collecting process, and enhancing alcohol productivity of Zymomonas bacteria. (NEDO)

  7. Process development and modeling of fluidized-bed reactor with coimmobilized biocatalyst for fuel ethanol production

    Science.gov (United States)

    Sun, May Yongmei

    This research focuses on two steps of commercial fuel ethanol production processes: the hydrolysis starch process and the fermentation process. The goal of this research is to evaluate the performance of co-immobilized biocatalysts in a fluidized bed reactor with emphasis on economic and engineering aspects and to develop a predictive mathematical model for this system. The productivity of an FBR is higher than productivity of a traditional batch reactor or CSTR. Fluidized beds offer great advantages over packed beds for immobilized cells when small particles are used or when the reactant feed contains suspended solids. Plugging problems, excessive pressure drops (and thus attrition), or crushing risks may be avoided. No mechanical stirring is required as mixing occurs due to the natural turbulence in the fluidized process. Both enzyme and microorganism are immobilized in one catalyst bead which is called co-immobilization. Inside this biocatalyst matrix, starch is hydrolyzed by the enzyme glucoamylase to form glucose and then converted to ethanol and carbon dioxide by microorganisms. Two biocatalysts were evaluated: (1) co-immobilized yeast strain Saccharomyces cerevisiae and glucoamylase. (2) co-immobilized Zymomonas mobilis and glucoamylase. A co-immobilized biocatalyst accomplishes the simultaneous saccharification and fermentation (SSF process). When compared to a two-step process involving separate saccharification and fermentation stages, the SSF process has productivity values twice that given by the pre-saccharified process when the time required for pre-saccharification (15--25 h) was taken into account. The SSF process should also save capital cost. The information about productivity, fermentation yield, concentration profiles along the bed, ethanol inhibition, et al., was obtained from the experimental data. For the yeast system, experimental results showed that: no apparent decrease of productivity occurred after two and half months, the productivity

  8. Dicty_cDB: Contig-U12802-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available cobacter cetorum strain MIT-0... 38 0.23 AF237484_1( AF237484 |pid:none) Dirofilaria immitis intermed...87 ( O97594 ) RecName: Full=Structural maintenance of chromosomes pro... 36 0.87 U00680_1( U00680 |pid:none) Brugia malayi intermed...1305( CP000879 |pid:none) Petrotoga mobilis SJ95, complet... 38 0.30 (Q9BZF9) RecName: Full=Uveal autoantigen with coiled...ns BAC clone RP11-764E7 from 2, complet... 34 0.79 6 ( FK620261 ) 454GmaGlobSeed354893 Soybean Seed...ditis elegans clone Y71H2X, *** SEQUENCI... 38 4.5 7 ( AC146972 ) Medicago truncatula clone mth2-128d9, compl

  9. Summerhouse dialogues between mobilier and immobilier

    DEFF Research Database (Denmark)

    Reeh, Henrik

    2017-01-01

    Addressing processes of cultural memory and mental appropriation in leisure architecture, this study relies on the fact that, in Denmark, summerhouses are often sold with furniture and objects representing the former owners and their ways of life. The theoretical starting point is formed by a dis......Addressing processes of cultural memory and mental appropriation in leisure architecture, this study relies on the fact that, in Denmark, summerhouses are often sold with furniture and objects representing the former owners and their ways of life. The theoretical starting point is formed...

  10. [Predominant strains of polycyclic aromatic hydrocarbon-degrading consortia from deep sea of the Middle Atlantic Ridge].

    Science.gov (United States)

    Cui, Zhisong; Shao, Zongze

    2009-07-01

    In order to identify the predominant strains of polycyclic aromatic hydrocarbon (PAH)-degrading consortia harboring in sea water and surface sediment collected from deep sea of the Middle Atlantic Ridge. We employed enrichment method and spread-plate method to isolate cultivable bacteria and PAHs degraders from deep sea samples. Phylogenetic analysis was conducted by 16S rRNA gene sequencing of the bacteria. Then we analyzed the dominant bacteria in the PAHs-degrading consortia by denaturing gradient gel electrophoresis (DGGE) combined with DNA sequencing. Altogether 16 cultivable bacteria were obtained, including one PAHs degrader Novosphingobium sp. 4D. Phylogenetic analysis showed that strains closely related to Alcanivorax dieselolei NO1A (5/16) and Tistrella mobilis TISTR 1108T (5/16) constituted two biggest groups among the cultivable bacteria. DGGE analysis showed that strain 4L (also 4M and 4N, Alcanivorax dieselolei NO1A, 99.21%), 4D (Novosphingobium pentaromativorans US6-1(T), 97.07%) and 4B (also 4E, 4H and 4K, Tistrella mobilis TISTR 1108T, > 99%) dominated the consortium MC2D. While in consortium MC3CO, the predominant strains were strain 5C (also 5H, Alcanivorax dieselolei NO1A, > 99%), uncultivable strain represented by band 5-8 (Novosphingobium aromaticivorans DSM 12444T, 99.41%), 5J (Tistrella mobilis TISTR 1108T, 99.52%) and 5F (also 5G, Thalassospira lucentensis DSM 14000T, degrading consortia in sea water and surface sediment of Middle Atlantic Ridge deep sea, with Novosphingobium spp. as their main PAHs degraders.

  11. Visualizing phosphodiester-bond hydrolysis by an endonuclease

    DEFF Research Database (Denmark)

    Molina, Rafael; Stella, Stefano; Redondo, Pilar

    2015-01-01

    The enzymatic hydrolysis of DNA phosphodiester bonds has been widely studied, but the chemical reaction has not yet been observed. Here we follow the generation of a DNA double-strand break (DSB) by the Desulfurococcus mobilis homing endonuclease I-DmoI, trapping sequential stages of a two-metal-...

  12. The Type 1 Homodimeric Reaction Center in Heliobacterium modesticaldum

    Energy Technology Data Exchange (ETDEWEB)

    Golbeck, John [Pennsylvania State Univ., University Park, PA (United States)

    2018-01-15

    In this funding period, we (i) found that strong illumination of Heliobacterium modesticaldum cells results in saturation of the electron acceptor pool, leading to reduction of the acceptor side and the creation of a back-reacting state that gives rise to delayed fluorescence; (ii) noted that when the FX cluster is reduced in purified reaction centers, no electron transfer occurs beyond A0, even though a quinone is present; (iii) observed by photochemically induced dynamic nuclear polarization (photo-CIDNP) studies of whole cells of Heliobacterium mobilis that primary charge separation is retained even after conversion of the majority of BChl g to Chl aF. ; and (iv) purified a homogeneous preparation of reaction center cores, which led to promising crystallization trials to obtain a three-dimensional structure.

  13. Caçambas coletoras de resíduos da construção e demolição no contexto do mobiliário urbano: uma questão de saúde pública e ambiental Containers for construction and demolition waste as urban furnishing: an environmental and public health issue

    Directory of Open Access Journals (Sweden)

    Joyce Maria de Araujo

    2007-04-01

    Full Text Available A utilização de caçambas metálicas em áreas públicas para acondicionar resíduos da construção e demolição-RCD tem sido incrementada, em cidades brasileiras, a partir da década de 1990, contribuindo para o adensamento do mobiliário urbano e modificando a paisagem urbana. Este equipamento é utilizado para confinar os resíduos de modo a impedir sua dispersão no ambiente, facilitar sua coleta e transporte e evitar a exposição de moradores e transeuntes. A despeito dessas vantagens, as caçambas representam um perigo ao ambiente e à saúde pública. Com objetivo de verificar a interferência das caçambas nas ruas e calçadas e identificar situações de risco, foi realizado um estudo de campo envolvendo 58 caçambas estacionadas em 5 diferentes bairros da cidade de São Paulo. Aspectos como localização e disposição, identificação e uso de pintura reflexiva para prevenção de acidentes com veículos automotivos e conteúdo da caçamba foram observados. Os resultados indicaram a presença de não-conformidades, na maioria dos casos observados, como: localização inadequada, pintura reflexiva não existente ou apagada, quantidade excessiva de resíduos, presença de matéria orgânica ou resíduos perigosos, objetos cortantes ou pontiagudos extrapolando os limites da caçamba, dentre outros. Conclui-se que é necessário desenvolver uma abordagem integrada e ecossistêmica para estes elementos do mobiliário urbano, de modo a contemplar, além da questão de gerenciamento dos RCD, aspectos de saúde pública e ambiental e, ao mesmo tempo, preservar os valores estéticos e a paisagem urbana. Dessa forma, o emprego de caçambas coletoras de RCD pode trazer benefícios que contribuam para a qualidade de vida nas cidades brasileiras.The use of metallic waste containers in public areas for storage of construction and demolition wastes-C&D debris was introduced in Brazilian cities in the 1990's, becoming a piece of urban

  14. A site-specific endonuclease encoded by a typical archaeal intron

    DEFF Research Database (Denmark)

    Dalgaard, Jacob; Garrett, Roger Antony; Belfort, Malene

    1993-01-01

    The protein encoded by the archaeal intron in the 23S rRNA gene of the hyperthermophile Desulfurococcus mobilis is a double-strand DNase that, like group I intron homing endonucleases, is capable of cleaving an intronless allele of the gene. This enzyme, I-Dmo I, is unusual among the intron...

  15. Alkaline/peracetic acid as a pretreatment of lignocellulosic biomass for ethanol fuel production

    Science.gov (United States)

    Teixeira, Lincoln Cambraia

    Peracetic acid is a lignin oxidation pretreatment with low energy input by which biomass can be treated in a silo type system for improving enzymatic digestibility of lignocellulosic materials for ethanol production. Experimentally, ground hybrid poplar wood and sugar cane bagasse are placed in plastic bags and a peracetic acid solution is added to the biomass in different concentrations based on oven-dry biomass. The ratio of solution to biomass is 6:1; after initial mixing of the resulting paste, a seven-day storage period at about 20°C is used in this study. As a complementary method, a series of pre-pretreatments using stoichiometric amounts of sodium hydroxide and ammonium hydroxide based on 4-methyl-glucuronic acid and acetyl content in the biomass is been performed before addition of peracetic acid. The alkaline solutions are added to the biomass in a ratio of 14:1 solution to biomass; the slurry is mixed for 24 hours at ambient temperature. The above procedures give high xylan content substrates. Consequently, xylanase/beta-glucosidase combinations are more effective than cellulase preparations in hydrolyzing these materials. The pretreatment effectiveness is evaluated using standard enzymatic hydrolysis and simultaneous saccharification and cofermentation (SSCF) procedures. Hybrid poplar wood pretreated with 15 and 21% peracetic acid based on oven-dry weight of wood gives glucan conversion yields of 76.5 and 98.3%, respectively. Sugar cane bagasse pretreated with the same loadings gives corresponding yields of 85.9 and 93.1%. Raw wood and raw bagasse give corresponding yields of 6.8 and 28.8%, respectively. The combined 6% NaOH/15% peracetic acid pretreatments increase the glucan conversion yields from 76.5 to 100.0% for hybrid poplar wood and from 85.9 to 97.6% for sugar cane bagasse. Respective ethanol yields of 92.8 and 91.9% are obtained from 6% NaOH/15% peracetic acid pretreated materials using recombinant Zymomonas mobilis CP4/pZB5. Peracetic acid

  16. Ethanol production in fermentation of mixed sugars containing xylose

    Science.gov (United States)

    Viitanen, Paul V [West Chester, PA; Mc Cutchen, Carol M [Wilmington, DE; Li,; Xu, [Newark, DE; Emptage, Mark [Wilmington, DE; Caimi, Perry G [Kennett Square, PA; Zhang, Min [Lakewood, CO; Chou, Yat-Chen [Lakewood, CO; Franden, Mary Ann [Centennial, CO

    2009-12-08

    Xylose-utilizing Z. mobilis strains were found to have improved ethanol production when grown in medium containing mixed sugars including xylose if sorbitol or mannitol was included in the medium. The effect was seen in concentrations of mixed sugars where no growth lag period occurs, as well as in higher sugars concentrations.

  17. : tous les projets | Page 225 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Au Chili, une société civile dynamique et mobilisée se sert des nouvelles technologies numériques pour transformer les modes de participation à la vie politique. Date de début : 17 novembre 2011. End Date: 17 mai 2014. Sujet: INFORMATION TECHNOLOGY, COMPUTER NETWORKS, CHILE, Democracy, Civil society, ...

  18. Comportamento recente do setor florestal madeireiro no Estado do Pará, Brasil Recent behavior of the section forest lumberman in the State of Pará, Brazil

    Directory of Open Access Journals (Sweden)

    Ricardo Bruno Nascimento dos Santos

    2009-06-01

    Full Text Available Os objetivos deste trabalho foram analisar o comportamento das exportações de madeira e identificar os municípios especializados nas atividades florestal e de madeira e mobiliário, no período de 1998 a 2004. A metodologia utilizada foi a taxa geométrica de crescimento (TGC, bem como o índice de concentração normalizado (ICN. Os resultados indicaram que as exportações cresceram a uma TGC acima de 14% ao ano. Foram identificados 25 municípios especializados em madeira e mobiliário e cinco na atividade florestal.The objective of this work was to analyze the behavior of wood exports and to identify the municipalities specialized on forestry, wood and furniture activities, in the period from 1998 to 2004. The methodology applied was the rate of geometric growth (RGG and the normalized index of concentration (NIC. The results showed that the exports grew at a rate of over 14% a year. Furthermore, twenty-five municipalities were identified as being specialized in wood and furniture; and five in forestry activities.

  19. La fermentation éthanolique. Les microorganismes Ethanol Fermentation. The Microorganisms

    Directory of Open Access Journals (Sweden)

    Ballerini D.

    2006-11-01

    Full Text Available Cette étude précise l'état actuel des connaissances concernant la fermentation éthanolique, d'un point de vue microbiologique. Outre les microorganismes utilisés depuis longtemps, sont décrites les nouvelles espèces de levures et de bactéries capables de transformer en éthanol des substrats aussi divers que les composés cellulosiques et hémicellulosiques issus de la biomasse et leurs produits d'hydrolyse. Pour la fermentation des substrats traditionnels tels que les mélasses et les jus d'extraction de plantes sucrières, ou encore l'amidon de maïs, les performances des levures du genre Saccharomyces sont comparées à celles des bactéries du genre Zymomonas. This review gives the state-of-the-art of what is known about ethanol fermentation from the microbiological viewpoint. In addition to the microorganisms that have been used for a long time, it describes new species of yeasts and bacteria capable of transforming, in ethanol, substrates including such different ones as cellulosic and hemicellulosic compounds issuing from biomass and their hydrolysis products. For the fermentation of traditional substrates such as molasses and juices extracted from sugar plants, or cornstarch, the performances of yeasts of the Saccharomyces type are compared to those of bacteria of the Zymomonas type.

  20. : tous les projets | Page 246 | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Au cours des derniers mois, des centaines de milliers de citoyens en Algérie, au Maroc et en Tunisie se sont mobilisés pour exiger une plus grande responsabilité et légitimité du gouvernement. Date de début : 1 avril 2011. End Date: 30 avril 2014. Sujet: SOCIAL MOVEMENTS, DEMOCRATIZATION. Région: Algeria ...

  1. Introduction La gouvernance de la santé en Afrique : état des lieux

    African Journals Online (AJOL)

    Conseil pour le développement de la recherche en sciences sociales en Afrique, 2017. (ISSN : 0850 3907 ). Introduction ... histoire, droit, économie, science politique, études féministes et de genre. En lisant ce numéro, ... Sur le plan méthodologique, les auteurs ont mobilisé plusieurs outils de collecte des données, dont, ...

  2. Development Cooperation in a Fractured Global Order: An Arduous ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Repenser la légitimité politique : inclusion des citoyens et médias sociaux numériques. Au Chili, une société civile dynamique et mobilisée se sert des nouvelles technologies numériques pour transformer les modes de participation à la vie politique. Voir davantageRepenser la légitimité politique : inclusion des citoyens et ...

  3. Résultats de recherche | Page 18 | CRDI - Centre de recherches ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Interventions de recherche rapides de l'International Crisis Group - s'attaquer aux défis en matière de gouvernance et de sécurité. Au cours des derniers mois, des centaines de milliers de citoyens en Algérie, au Maroc et en Tunisie se sont mobilisés pour exiger une plus grande responsabilité et légitimité du gouvernement ...

  4. Repenser la légitimité politique : inclusion des citoyens et médias ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Repenser la légitimité politique : inclusion des citoyens et médias sociaux numériques. Au Chili, une société civile dynamique et mobilisée se sert des nouvelles technologies numériques pour transformer les modes de participation à la vie politique. Ce projet de recherche consistera à recueillir des données sur la manière ...

  5. LE MARCHE FINANCIER EN ALGERIE : SITUATION ET ...

    African Journals Online (AJOL)

    Administrateur

    marché en l'occurrence le marché financier ne représente pas un problème strictement ... variés de par le monde. Dans les pays en transition, la performance du .... Les valeurs mobilières sont constituées de deux types de titres : les titres de .... La COSOB (commission d'organisation et de surveillance des opérations de ...

  6. Kraniomandibulární syndrom - možnosti diagnostiky a terapie z pohledu fyzioterapeuta

    OpenAIRE

    Damcová, Kateřina

    2016-01-01

    Abstracts Title: Craniomandibular Syndrome - Diagnosis and Therapy from the Perspective of a Physiotherapist Objectives: The thesis deals with problems of diagnosis and therapeutic intervention in pain, that originates in craniomandibular area from the perspective of the physiotherapist, and especially functional disorders of myofascial substrate. The goal was to determine whether and to what extent can be the pain relieved, through selected therapeutic methods (soft tissue techniques, mobili...

  7. Caracterización microbiológica del pulque y cuantificación de su contenido de etanol mediante espectroscopia Raman

    OpenAIRE

    Cervantes-Contreras, M.; Pedroza, A. M

    2008-01-01

    En este trabajo se llevo a cabo un estudio microbiológico del pulque, una bebida tradicional alcohólica mexicana, para cuatro diferentes tiempos de fermentación. Estudiamos las diferentes poblaciones de Saccharomyces sp, Zymomonas sp y Leunocostoc sp y evaluamos las diferentes concentraciones de azucares, proteínas y etanol. Se presenta un método de análisis simple y exacto para la determinación del contenido de alcohol en el pulque, basado en espectroscopia Raman. In this work a microbiol...

  8. Arguments pour une émancipation de la stylistique structurale de Riffaterre

    Directory of Open Access Journals (Sweden)

    Vessah Ngou Donald

    2014-07-01

    Au final, la pensée riffaterrienne ne saurait être confinée aux structures linguistiques et soumise à ses lois, puisqu’elle pose prioritairement le récepteur au cœur de son processus autant que de ses limites, en faisant de lui le garant et le véritable modulateur de la théorie. Elle s’impose au demeurant comme théorie, non pas tant par les démarches qu’elle définit a priori, que par le fait qu’elle prédit l’expérience et les contours engendrés. Il apparaît surtout que la stylistique de la réception qu’elle incarne, pour autant qu’elle soit une véritable praxis, modulaire, instable, n’en est pas moins descriptible et cohérente dans ses relations avec les connaissances mobilisées par l’analyste.

  9. Interventions de recherche rapides de l'International Crisis Group - s ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Au cours des derniers mois, des centaines de milliers de citoyens en Algérie, au Maroc et en Tunisie se sont mobilisés pour exiger une plus grande responsabilité et légitimité du gouvernement. Les gens ont manifesté dans les rues, souvent au péril de leur vie, pour exiger la démission de dirigeants de régimes autoritaires.

  10. Vehicle Mobility Assessment for Project Wheels Study Group

    Science.gov (United States)

    1972-07-01

    cash savings p’Asible through the elimination of special military automotive features, such as front-wheel 1 Idrive , or the use of commercial vehicles...E12. (12) off-,,,d mobiliY profile 4x4 0ruck, c 2Z4< 20 ,ernn It Iot "- III IIIII III I I I IIII A%. West Germany 0A * s ps ArizonazD • Ř’.. • D

  11. Bewertung des Aufbaus einer Ladeinfrastruktur für eine Redox-Flow-Batteriebasierte Elektromobilität

    OpenAIRE

    Funke, Simon Árpád; Wietschel, Martin

    2012-01-01

    Eine Erreichung ambitionierter internationaler Klimaziele ist bei wachsendem Mobiliätsbedarf ohne Elektromobilität nicht möglich. Elektromobilität in Verbindung mit regenerativen Energien wird als wichtiger Baustein zur Reduktion der Treibhausgasemissionen angesehen. Gleichzeitig ist die Verbreitung von Elektrofahrzeugen gering, da diese gegenüber Verbrennungsfahrzeugen mit Einschränkungen verbunden sind. Neben den Anschaffungsausgaben stehen lange Ladezeiten und eine beschränkte Reichweite d...

  12. TRANÇADO: COMPUTATIONAL DESIGN THINKING APPLIED TO A URBAN FURNITURE PROJECT

    Directory of Open Access Journals (Sweden)

    Dyego Digiandomenico

    2017-11-01

    Full Text Available Este trabalho apresenta a pesquisa, projeto e construção do mobiliário urbano Trançado, localizado no Largo da Batata, um espaço público na cidade de São Paulo. O artigo discute o desenvolvimento do algoritmo, os parâmetros, a performance do projeto e o uso das tecnologias de prototipagem rápida e da fabricação digital para a análise do modelo e das técnicas construtivas, assim como descreve detalhes da execução e instalação final. Oferece também dados da pesquisa de pós-ocupação, assim como discute a relação entre o projeto do mobiliário e seu uso real, visto que participaram do processo agentes de diferentes áreas, como profissionais, organizações e sociedade civil. A pesquisa contribui ao relatar e discutir a qualidade do processo aplicado, não se concentrando apenas em analisar o resultado do objeto arquitetônico, mas produzir insumos para a reflexão e avanço da aplicação dos recursos computacionais no processo de projeto em arquitetura e design.

  13. La gestion de l'eau et des déchets améliore la santé au Cameroun ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    5 déc. 2011 ... L'équipe a conçu des récipients pour la conservation de l'eau qui réduisent la contamination, étendu le système municipal d'alimentation en eau potable, organisé la collecte locale des déchets solides, construit des latrines non polluantes et aménagé des voies piétonnes. Elle a aussi mobilisé la ...

  14. Digital Marketing

    OpenAIRE

    Stefano Pace; Margherita Pagani; Silvia Vianello

    2011-01-01

    Lo sviluppo di nuove modalità di commercio elettronico via web, le nuove piattaforme di Tv digitale interattiva (t-commerce) e le applicazioni mobili (m-commerce) hanno suscitato rilevante attenzione allo studio del comportamento del consumatore nei nuovi contesti digitali. Per le aziende è rilevante comprendere i fattori che influenzano l’intenzione di acquisto e adozione dei beni e servizi online da parte dei consumatori e il comportamento di fruizione delle singole piattaforme digitali...

  15. Reconstruction après le tsunami dans un contexte de guerre | Page ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Le 26 décembre 2004, un tsunami a ravagé la majeure partie des régions côtières de la province d'Aceh, en Indonésie, ainsi que les côtes est et sud du Sri Lanka. La communauté internationale s'est mobilisée massivement pour secourir les populations en détresse et a acheminé une aide considérable aux zones ...

  16. Evaluation of ethanol production from pito mash using Zymomonas ...

    African Journals Online (AJOL)

    Joseph Asankomah Bentil

    technology for the conversion of lignocelluloses to bioethanol should be decided on the basis of overall economics (lowest cost), environmental (pollutants), and energy (higher efficiencies). Many investigations have been performed on the appropriate technology for the conversion of the lignocellulosic to ethanol as well as.

  17. Strumenti Urbani. Tecnologie mobili come dispositivi di improvvisazione corporea

    Directory of Open Access Journals (Sweden)

    Elena Biserna

    2013-06-01

    Full Text Available Dal Walkman ai lettori MP3, negli ultimi decenni le tecnologie audio portatili sono prepotentemente entrate in abitudini e rituali quotidiani, assumendo un ruolo sostanziale nella cultura uditiva e urbana ma anche, e soprattutto, nelle nostre modalità di attraversare gli spazi. L’uso di questi objets nomades (Attali 1977 interviene non solo sulle forme di consumo musicale, ma anche sul rapporto con lo spazio, con il contesto attraversato

  18. Mobiliųjų telefonų vartotojų elgsena

    OpenAIRE

    Adomavičienė, Dinara; Kungytė, Viktorija

    2010-01-01

    Mobile phone manufacturers supply the market with a large range of mobile phones with their evolving functions, offering consumers a range of discounts and convenient ways to purchase. The article aims to explore what manufacturers of mobile phone choose today's consumers. What are the most used functions of the mobile phones? Do the financial potential of the consumers have the impact on the price of the mobile phone? The objective of the study is to reveal the behaviour of the consumers whe...

  19. Análise da carga de trabalho de analistas de sistemas e dos distúrbios osteomusculares

    Directory of Open Access Journals (Sweden)

    Bruno Maia de Guimarães

    Full Text Available OBJETIVOS: O objetivo desta pesquisa foi realizar avaliação das condições ergonômicas de analistas de sistemas, com a finalidade de conhecer os fatores geradores de sobrecargas físicas e cognitivas, suas repercussões sobre os trabalhadores e propor melhorias para a diminuição dessas sobrecargas. METODOLOGIA: Foram utilizados o método SHTM (sistema homem-tarefa-máquina de avaliação ergonômica; o diagrama de Corlett, para a avaliação do desconforto corporal; o questionário de avaliação do mobiliário; e o NASA-TLX, para a avaliação de carga mental de trabalho. RESULTADOS: Foram encontradas as prevalências de dor na coluna lombar (71% e na coluna cervical (64% dos entrevistados. Após a avaliação da carga mental de trabalho, foi observado que a demanda mental foi a mais exigida entre os analistas de sistemas e a média da carga global foi de 13,23. CONCLUSÃO: Pode-se concluir que a alta prevalência de dor musculoesquelética pode ser causada pela presença de mobiliário inadequado, pela adoção de posturas incorretas e pela alta exigência mental das atividades desenvolvidas.

  20. Process Improvements to Biomass Pretreatment of Fuels and Chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Teymouri, Farzaneh [Michigan Biotechnology Inst., Lansing, MI (United States)

    2015-05-30

    demonstrated; >94% ammonia recovery, >75% sugar yields at high solid loading, and complete utilization of the sugars for ethanol production at the 2500 liter scale. Fermentation tests were performed using Zymomonas mobilis 8b and densified AFEX-treated corn stover at >20% solid loading. The obtained titer (~60g/l), productivity (2.5 g/L-h), and yield (330 L/tonne of biomass) exceeded the performance targets set out by NREL. The key findings from these efforts are: no contamination was observed, no cleanup of the sugar stream was required, and no major nutrient addition was required. Our economic model shows that using a packed bed design for the AFEX process and pelleted AFEX-treated biomass reduces the ethanol production cost by 24% when compared to using the traditional AFEX design.

  1. Proceso de internacionalización de la fábrica Ecuamueble

    OpenAIRE

    Carrera Crespo, Timoleon

    2010-01-01

    El presente estudio analiza la forma en que una empresa o industria nacional, en este caso una fábrica de muebles metálicos, que maneja una amplia cobertura nacional, y que posee una muy buena capacidad instalada que esta subutilizada debido a que el mercado nacional está en buena parte ya atendido, pueda llegar a internacionalizarse, encontrando mercados en países extranjeros que brinden las facilidades necesarias para el efecto y que además sean potenciales mercados para este tipo de mobili...

  2. La psychologie du comportement de Pierre Naville (1904-1993).

    OpenAIRE

    Carbonel , Frédéric

    2012-01-01

    working paper ; preprint non référencé; Acquis au marxisme dès 1925, militant trotskiste depuis 1928, Pierre Naville est mobilisé en septembre 1939 comme simple caporal au train des Equipages sur Paris puis au secrétariat du cabinet Daladier au tout début de la " drôle de guerre ". On oublie trop souvent l'œuvre critique de Pierre Naville en matière de psychologie essentiellement développée entre 1942 et 1945.

  3. Hypsipyla grandella em Mogno (Swietenia macrophylla): Situação Atual e Perspectivas Hypsipyla grandella in Mahogany (Swietenia macrophylla): Current Situation and Perspectives

    OpenAIRE

    Alexandre Mehl Lunz; Marcílio José Thomazini Thomazini; Maria Carolina Blassioli Moraes; Edinelson José Maciel Neves; Telma Fátima Coelho Batista; Juliana Degenhardt; Lindáurea Alves de Sousa; Orlando Shigueo Ohashi

    2010-01-01

    A madeira de mogno, Swietenia macrophylla King, é valorizada no mercado internacional por sua beleza e durabilidade para fins nobres, como mobiliários e decoração. Quaisquer tentativas de plantios comerciais dessa espécie de modo a reduzir a pressão exercida pela sua exploração seletiva invariavelmente fracassam devido à incidência da broca do ponteiro do mogno, Hypsipyla grandella (Zeller). Embora alguns trabalhos tenham obtido relativo sucesso em apresentar técnicas de controle sob...

  4. Meccanica razionale

    CERN Document Server

    Finzi, Bruno

    1955-01-01

    Introduzione ; teorie introduttive ; calcolo vettoriale ; calcolo tensoriale ; cinematica : punti e sistemi mobili, spostamento, movimento, velocità, accelerazione, cinematica relativistica ; statica : nozioni preliminari e statica del punto, statica dei corpi rigidi, statica dei sistemi deformabili, principio dei lavori virtuali dinamica fisica : concetti e leggi fondamentali, azioni e caratteristiche meccaniche, meccanica relativa, meccanica relativistica, dimensioni e unità di misura delle quantità meccaniche ; calcolo del movimento : dinamica del punto materiale, dinamica del corpo rigido, dinamica dei sistemi, dinamica dei continui deformabili, dinamica impulsiva, meccanica statistica.

  5. Link2U: un social network aumentato su dispositivi mobili

    Directory of Open Access Journals (Sweden)

    Monica Sebillo

    2012-04-01

    Full Text Available Negli ultimi anni il connubio mobile entertainment e social network ha attirato un notevole interesse da parte dispecifici settori che, nonostante le criticità del momento, hanno deciso di investire nella realizzazione di ambienti esoluzioni di intrattenimento/divertimento, un fattore chiave alla base del miglioramento della tecnologia.Link2U: augmenting social networks on mobile devicesNowadays, modern mobile devices have become real person-al  computers  that  increase  the  ability  of  building/extending existing applications by combining several technologies such as camera, GPS, 3D graphics and permanent Internet connec-tion. The  resulting  integration  of  such  technologies  allows  to  run complex  applications,  such  as  augmented  reality  and  Social Networks. The goal of our current research is to support mobile users’ daily activities, by developing advanced solutions which take into account principles of human-computer interac-tion and usability. In this paper we propose to exploit the potential of the aug-mented reality and the ability to communicate of social net-works to create a mobile social network, where each commu-nity user may exploit advanced location based services, such as navigation through a two dimensional map, exploration of an area through a camera mode, and identification of points of interest embedded in an augmented reality environment.

  6. Link2U: un social network aumentato su dispositivi mobili

    Directory of Open Access Journals (Sweden)

    Monica Sebillo

    2012-04-01

    Full Text Available Negli ultimi anni il connubio mobile entertainment e social network ha attirato un notevole interesse da parte dispecifici settori che, nonostante le criticità del momento, hanno deciso di investire nella realizzazione di ambienti esoluzioni di intrattenimento/divertimento, un fattore chiave alla base del miglioramento della tecnologia. Link2U: augmenting social networks on mobile devices Nowadays, modern mobile devices have become real person-al  computers  that  increase  the  ability  of  building/extending existing applications by combining several technologies such as camera, GPS, 3D graphics and permanent Internet connec-tion. The  resulting  integration  of  such  technologies  allows  to  run complex  applications,  such  as  augmented  reality  and  Social Networks. The goal of our current research is to support mobile users’ daily activities, by developing advanced solutions which take into account principles of human-computer interac-tion and usability. In this paper we propose to exploit the potential of the aug-mented reality and the ability to communicate of social net-works to create a mobile social network, where each commu-nity user may exploit advanced location based services, such as navigation through a two dimensional map, exploration of an area through a camera mode, and identification of points of interest embedded in an augmented reality environment.

  7. The mobilies of chiral molecular cluster ions in He gas

    International Nuclear Information System (INIS)

    Saito, Kazuyuki; Matoba, Shiro; Koizumi, Tetsuo; Kojima, Takao M; Tanuma, Hajime; Shiromaru, Haruo

    2012-01-01

    We measured the mobilities of Li + -(2-butanol) and Li + -(limonene) ions in He gas at room temperature using a drift tube mass spectrometer. The zero field mobilities of Li + -(2-Butanol) and Li + -(Limonene) were much lower than the polarization limit, indicating that the geometric collision cross-sections between the cluster ions and He atom were larger than the cross-sections predicted by the presence of a polarization force alone.

  8. De la mutualisation à la coopération. : Élaboration d’un référentiel de connaissances en santé au travail.

    OpenAIRE

    Masse , Max; Madec , Laurent

    2015-01-01

    International audience; Dans le cadre de la rationalisation de l’appareil de formation initiale de ses 150 écoles de service public, le Ministère de la fonction publique française a mobilisé des professionnels issus de ces écoles pour engager des travaux de mutualisation pédagogique à travers la conception de référentiels de compétences-formation. Nous montrerons que cette mutualisation n’a permis de ne constituer que des référentiels de connaissances potentiellement actionnables (Penalva) po...

  9. A indústria de fundos de investimento: o poder regulamentar como garantia ao investidor e a responsabilidade civil do administrador de fundos

    OpenAIRE

    Morone, José Oswaldo Fernandes Caldas

    2007-01-01

    A Indústria de Fundos de Investimento , de forma concisa e objetiva, analisa os fundos de investimento regulados pela Comissão de Valores Mobiliários, identificando os principais aspectos de gestão, administração e governança corporativa deste segmento tão importante do Sistema Financeiro Nacional, concomitantemente à indispensável proteção do pequeno investidor e da responsabilidade do administrador. Os fundos de investimento, na sua aparente simplicidade, são dos fenômenos mais complexos...

  10. Utilização Potencial do Lenho de Acacia melanoxylon: a Crescer em Povoamentos Puros ou Mistos com Pinus pinaster - pela Indústria Florestal Portuguesa

    OpenAIRE

    Santos, António; Teixeira, Andreia; Anjos, Ofélia; Simões, Rogério; Nunes, Lina; Machado, José S.; Tavares, Mário

    2007-01-01

    A Acacia melanoxylon R. Br. (acácia-austrália ou austrália) cresce bem em Portugal, em povoamentos puros ou mistos com Pinus pinaster Aiton, ainda que apresente fortes constrangimentos ecológicos e legais. Apesar de algumas dificuldades, por exemplo na secagem, a madeira de austrália é usada em mobiliário e produtos manufacturados devido, principalmente, à sua textura e cor escura. Pode também ser usada para pasta, sendo plantada em muitos países com esse propósito juntamente com Acacia mangi...

  11. Discours performatifs et constructions politiques de l’identité ethnique : restructuration des rapports entre minorités et pouvoirs publics au Mexique, le cas totonaque.

    Directory of Open Access Journals (Sweden)

    Nicolas Ellison

    2005-02-01

    Full Text Available Le propos de cet exposé est de montrer, à partir de l’étude de terrain concernant le mouvement ethnico-écologique des Indiens totonaques (Mexique central, comment la référence au conflit du Chiapas et l’appropriation des discours sur les droits indigènes et le développement durable sont mobilisés par les organisations indiennes, l’Eglise et les partis politiques pour redéfinir la relation entre les minorités et les pouvoirs publics.

  12. Le temple-mémorial de Château-Thierry : approche monographique

    Directory of Open Access Journals (Sweden)

    Aline Magnien

    2005-09-01

    Full Text Available Le temple-mémorial de Château-Thierry, inauguré en 1924 est réalisé par deux architectes : Paul-Philippe Cret et Achille-Henri Chauquet, L’édifice est décoré d’un vitrail-tableau intitulé La Fayette nous voilà ! représentant La Fayette accueillant le général Pershing et de verrières ornées de scènes tirées des Paraboles de l’artiste suisse Eugène Burnand par son fils David Burnand. La chaire et le mobilier ont été offerts par des paroisses américaines en souvenir des soldats tombés au front. Par son architecture, son mobilier et les circonstances de la commande, le temple de Château-Thierry méritait une étude.The American memorial church of Château-Thierry, dedicated in 1924 has been built by two architects, Paul-Philippe Cret and Achille-Henri Chauquet. The church is adorned by a stained glass church window showing La Fayette welcoming Pershing and by some others stained glasses representing parables by David Burnand from sketches of his father Eugène Burnand. American churches supplied the pulpit and other furniture to adorn the building in memory of the soldiers died in the battle front. By its architecture, its furniture and the circumstances of its edification, the memorial church of Château-Thierry deserves a study

  13. Bolivie

    Directory of Open Access Journals (Sweden)

    Jean-François Luneau

    2012-02-01

    Full Text Available A la demande de l’Ambassade de France à La Paz, deux missions ont été effectuées en Bolivie en 1995 et 1996 afin de participer, avec le Centre national de catalogage du patrimoine artistique, à la création d’une base de données sur le mobilier. Cette opération est rendue nécessaire pour tenter d’enrayer la sortie de nombreux objets d’art du territoire national, dont certains proviennent de vols commis dans les églises rurales. Pas moins de 11 000 fiches sur les objets mobiliers ont été remplies par les enquêteurs. Le projet a bénéficié de l’aide de l’Organisation des Etats Américains dès la fin des années 1970, puis de celle de l’Unesco dans les années 1980.In response to a request by the French Embassy in La Paz, two consultancy services were commissioned in Bolivia in 1995 and 1996 in order to set up a database for the National centre of registration for the movable heritage. This had become necessary in order to put a stop to the numbers of works of art leaving the country, many of which had been stolen from rural churches. No fewer than 11 000 notices have been completed by investigators. This programme was supported by the American states organisation as early as the late 1970s, and then by Unesco in the 1980s.

  14. Effects of iron-reducing bacteria and nitrate-reducing bacteria on the transformations of iron corrosion products, magnetite and siderite, formed at the surface of non-alloy steel

    International Nuclear Information System (INIS)

    Etique, Marjorie

    2014-01-01

    Radioactive waste is one of the major problems facing the nuclear industry. To circumvent this issue France plans to store vitrified high-level nuclear waste in a stainless steel container, placed into a non-alloy steel overpack, at a depth of 500 m in an argillaceous formation. The main iron corrosion products formed at the surface of the non-alloy steel are siderite (Fe II CO 3 ) and magnetite (Fe II Fe III 2 O 4 ). These compounds are formed in the anoxic conditions present in the nuclear waste repository and play a protective role against corrosion as a passive layer. This work aims to investigate the activity of nitrate-reducing bacteria (NRB, Klebsiella mobilis) and iron-reducing bacteria (IRB, Shewanella putrefaciens) during the transformation of siderite and magnetite, especially those involved in anoxic iron biogeochemical cycle. Klebsiella mobilis and Shewanella putrefaciens were first incubated with siderite or magnetite suspensions (high surface specific area) in order to exacerbate the microbial iron transformation, subsequently incubated with a magnetite/siderite film synthesized by anodic polarization at applied current density. The transformation of siderite and magnetite by direct or indirect microbial processes led to the formation of carbonated green rust (Fe II 4 Fe III 2 (OH) 12 CO 3 ). As a transient phase shared by several bacterial reactions involving Fe II and Fe III , this compound is the cornerstone of the anoxic iron biogeochemical cycle. The novelty of this thesis is the consideration of bacterial metabolisms of NRB and IRB often overlooked in bio-corrosion processes. (author) [fr

  15. Les activités communicatives des tuteurs en psychologie du développement et en pratiques à l’université

    OpenAIRE

    Olry-Louis, Isabelle

    2011-01-01

    Cet article vise à faire le point sur les activités communicatives déployées par les tuteurs en articulant la littérature propre à la psychologie du développement et celle qui décrit les pratiques d’accompagnement des nouveaux étudiants à l’université. Centré sur l’examen des processus langagiers, cognitifs et socio-affectifs mobilisés, l’article souligne les écarts entre le tutorat tel qu’il est étudié et tel qu’il est mis en pratique. Il conclut en proposant quelques pistes d’amélioration d...

  16. LA MEDITERRANEE DANS LES RELATIONS INTERNATIONALES DU XXE SIECLE

    OpenAIRE

    Lejeune , Dominique

    2010-01-01

    DEUG; Le monde est jugé dangereux et on voit resurgir les " ennemis héréditaires " ou des adversaires potentiels qui s'y substituent. De plus, l'expansion économique européenne provoque l'impatience d'ascension sociale, et la guerre va pouvoir libérer des énergies en 1914. Les ouvrages de guerre-fiction sont beaucoup plus nombreux après 1905 qu'auparavant ; la guerre est toujours présentée comme devant être courte, à cause de l'importance du nombre des mobilisés et du modernisme du matériel. ...

  17. Google Scholar, Google Print ... un nouvel entrant pour la diffusion de la recherche.

    OpenAIRE

    Ertzscheid, Olivier

    2005-01-01

    La diffusion des résultats de la recherche scientifique est un enjeu majeur pour l'économie et au-delà la société de la connaissance. Plusieurs nouveaux entrants bouleversent actuellement la carte des acteurs en ce domaine. Cet article propose une analyse des motivations, du positionnement et des enjeux mobilisés par l'arrivée de Google sur ce marché. Nous situons d'abord les effets de cette entrée sur l'évaluation de la recherche, et précisons comment se mettent en place de nouvelles pratiqu...

  18. Descobrir, explorar, apropriar: o design de interiores como elemento valorizador da arquitectura - um exemplo prático

    OpenAIRE

    Miranda, Ana

    2013-01-01

    A arquitectura de interiores, o design de interiores e decoração de interiores podem ser entendidos como manifestações de uma mesma arte, manifestações estas variando apenas na escala e na profundidade da intervenção, da edificação de paredes novas, à construção do mobiliário ou à edificação de revestimentos. Reconhecendo que estas manifestações da mesma arte têm em comum o facto de projectarem para o ser humano, é importante que a sociedade entenda o designer de interiores, como complemen...

  19. Pollution durable des sols par la chlordécone aux Antilles : comment la gérer ?

    OpenAIRE

    Cabidoche, Yves-Marie; Lesueur-Jannoyer, Magali

    2011-01-01

    La chlordécone, insecticide organochloré de synthèse, était utilisée dans les bananeraies antillaises avant 1993. Pourtant, elle contamine encore les ressources en eau, certaines denrées, et des organismes aquatiques. Très tôt, la recherche agronomique s’est mobilisée pour répondre aux questions posées pour la gestion de cette crise : Où sont les sols pollués? Est-ce une pollution durable ? La molécule est peu mobile. Des cartes de risques, fondées sur leur occupation rétrospective en bananer...

  20. Protein sequences and redox titrations indicate that the electron acceptors in reaction centers from heliobacteria are similar to Photosystem I

    Science.gov (United States)

    Trost, J. T.; Brune, D. C.; Blankenship, R. E.

    1992-01-01

    Photosynthetic reaction centers isolated from Heliobacillus mobilis exhibit a single major protein on SDS-PAGE of 47 000 Mr. Attempts to sequence the reaction center polypeptide indicated that the N-terminus is blocked. After enzymatic and chemical cleavage, four peptide fragments were sequenced from the Heliobacillus mobilis apoprotein. Only one of these sequences showed significant specific similarity to any of the protein and deduced protein sequences in the GenBank data base. This fragment is identical with 56% of the residues, including both cysteines, found in highly conserved region that is proposed to bind iron-sulfur center Fx in the Photosystem I reaction center peptide that is the psaB gene product. The similarity to the psaA gene product in this region is 48%. Redox titrations of laser-flash-induced photobleaching with millisecond decay kinetics on isolated reaction centers from Heliobacterium gestii indicate a midpoint potential of -414 mV with n = 2 titration behavior. In membranes, the behavior is intermediate between n = 1 and n = 2, and the apparent midpoint potential is -444 mV. This is compared to the behavior in Photosystem I, where the intermediate electron acceptor A1, thought to be a phylloquinone molecule, has been proposed to undergo a double reduction at low redox potentials in the presence of viologen redox mediators. These results strongly suggest that the acceptor side electron transfer system in reaction centers from heliobacteria is indeed analogous to that found in Photosystem I. The sequence similarities indicate that the divergence of the heliobacteria from the Photosystem I line occurred before the gene duplication and subsequent divergence that lead to the heterodimeric protein core of the Photosystem I reaction center.

  1. Fast coliform detection in portable microbe enrichment unit (PMEU) with Colilert(®) medium and bubbling.

    Science.gov (United States)

    Hakalehto, Elias; Heitto, Anneli; Heitto, Lauri

    2013-09-01

    Laboratory strains of coliforms Escherichia coli and Klebsiella mobilis were used to artificially contaminate water samples in two different cultivation and detection systems, without and with bubble flow. Samples were collected with an automated system (ASCS). The positive coliform signal caused the color change into yellow (at 550-570nm). This signal could also be transmitted on-line to cell phones. E. coli containing samples emitted UV fluorescence at 480-560nm when activated by UV light. If cultivation was started with inocula varying from 10,000 to 1cfu/ml, the positive detection was obtained between 2 and 18h, respectively, in Colilert medium using Coline PMEU device without gas bubbling. Accordingly, a single K. mobilis cell produced detectable growth in 18h. Various clinical E. coli strains were compared to each other with equal inoculum sizes, and they showed slight variations in the initiation and speed of growth. The gas bubble flow in PMEU Spectrion promoted the mixing and interaction of bacteria and indicator media and speeded the onset of growth. Carbon dioxide also accelerated bacterial growth. In the presence of vancomycin, the onset of E. coli culture growth was speeded up by the volatile outlet flow from previous cultures. In the last cultivation syringe in a series of five, the lag phase disappeared and the growth of the inoculum continued without major interruption. the stimulation of the cultures by the gas flow turned out to be a useful means for improving the detection of indicator bacteria. It could also be used in combination with antibiotic selection in the broth medium. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. La città come teatro / The City as a Theather

    Directory of Open Access Journals (Sweden)

    Jonathan Kirschenfeld

    2014-05-01

    Full Text Available Il lavoro di progettazione del nostro ufficio nel corso degli ultimi 15 anni comprende social housing, piscine pubbliche e progetti di teatri. Questi progetti apparentemente distanti condividono un filo comune che attraversa la loro forma concettuale se non fisica: il concetto di “stanza urbana” come teatro. In ogni caso, sia che si tratti di una piscina, di un teatro o di un’abitazione, mobili o adattabili a diversi siti, nel corso di questi progetti sono privilegiati gli spazi cosiddetti di “impegno sociale”. Queste stanze urbane, nelle parole di Aldo Rossi, agiscono per approntare la scena per il teatro della vita quotidiana.

  3. Flux d'énergie dans des systèmes d'élevage laitiers contrastés : élaboration d'indicateurs et analyse de la diversité inter et intra-territoire

    OpenAIRE

    Vigne, Mathieu

    2012-01-01

    Le doublement futur de la demande mondiale en produits laitiers nécessite de concevoir des systèmes plus productifs mais également écologiquement plus durables. Les objectifs de la thèse étaient i) d'évaluer l'intérêt de la prise en compte de l'ensemble des énergies mobilisées dans un système d'élevage (énergie fossile, énergie calorifique contenue dans les produits, énergie liée au travail humain et animal et énergie solaire) à travers des méthodes existantes ou originales pour développer de...

  4. Le genre, variable centrale de la violence sociale ?

    OpenAIRE

    Ayral , Sylvie; Raibaud , Yves

    2010-01-01

    Le but de cet article n'est pas de savoir si le genre est une variable centrale de la violence sociale mais comment cette hypothèse (qui induit la possibilité d'un changement social) est réfutée et quelles connaissances sont mobilisées à cet effet. Il s'agit d'identifier les modèles récurrents mis en œuvre par les « membres » (par exemple la communauté scientifique des sciences humaines et sociales) lorsqu'ils.elles examinent le sens de ces modèles par l'observation de « ce que les gens font ...

  5. Etienne Hofmann, Une erreur judiciaire oubliée : L’Affaire Wilfrid Regnault (1817-1818

    Directory of Open Access Journals (Sweden)

    Jean-Claude Farcy

    2009-12-01

    Full Text Available Cet ouvrage, remarquable par son érudition, livre au lecteur l’ensemble de la documentation disponible sur une erreur judiciaire peu connue, ne figurant pas dans les recueils consacrés à ce genre très particulier d’affaires judiciaires – sans doute parce que l’erreur n’a pas été légalement reconnue – et qui pourtant présente nombre des caractéristiques d’une « grande cause » avec l’intervention passionnée et très argumentée, en 1817, d’un écrivain - Benjamin Constant – dont les écrits mobilis...

  6. An atlas of classification. Signage between open shelves, the Web and the catalogue

    Directory of Open Access Journals (Sweden)

    Andrea Fabbrizzi

    2014-05-01

    Questa segnaletica è fondata sulla comunicazione cross-mediale, e integra le modalità comunicative della biblioteca a vari livelli, sia nel contesto dello stesso medium, sia tra media diversi: tra i cartelli sulle testate degli scaffali, tra questi cartelli e il sito web della biblioteca, tra il sito web e il catalogo. Per questo sistema integrato sono particolarmente adatti i dispositivi mobili come i tablet e gli smartphone, perché danno la possibilità di accedere al Web mentre ci si muove tra gli scaffali. Il collegamento diretto tra gli scaffali aperti classificati e il catalogo è reso possibile dai codici QR stampati sui cartelli.

  7. « Questions de Sciences, Enjeux Citoyens » : à la recherche de l’expression citoyenne

    OpenAIRE

    Blémus, Nicolas

    2011-01-01

    Mis en place en Île-de-France en 2009, le dispositif « Questions de Sciences, Enjeux Citoyens » permet à la population, toutes catégories sociales confondues, de débattre sur les enjeux de société liés à la recherche et à la technologie : le responsable du projet revient sur la méthodologie et les protocoles développés, les savoir-faire mobilisés et dresse un premier bilan de l’opération. Set up in the ‘Île de France’ (Paris region) in 2009, the programme Questions on Sciences, Citizen sta...

  8. Art et comportements symboliques au Paléolithique : quelques points de vue actuels

    OpenAIRE

    Paillet, Patrick

    2015-01-01

    Du temps de la reconnaissance à l'archéologie des grottes ornées Édouard Lartet et Édouard Piette principalement ont marqué le XIX ème siècle par leurs extraordi-naires découvertes d'art mobilier et leurs efforts pour les faire reconnaître par la communauté scien-tifique alors placée sous l'autorité dogmatique de Gabriel de Mortillet et d'Émile Cartailhac. Ils ont aussi oeuvré, non sans mal, pour en faire admettre l'antiquité et l'authenticité. Une grande partie du XX ème siècle fut celle des...

  9. Le détour, la pause et l'optimalité. Essai sur la distance et ses apports au transport et à l'urbanisme

    OpenAIRE

    L'HOSTIS, Alain

    2014-01-01

    La distance est un élément central pour la compréhension et pour l'action sur la ville et les territoires dans leurs liens avec les transports. Pourtant la distance n'a pas été considérée dans toutes ses potentialités dans les disciplines qui abordent la spatialité, c'est-à-dire la géographie, l'économie, la psychologie et la sociologie, et qui constituent les principaux gisements de savoirs académiques mobilisés par les spécialistes de l'urbanisme, de l'aménagement et des transports. L'inves...

  10. Les processus spatio-temporels: quelques notions et concepts préalables à leur représentation

    Directory of Open Access Journals (Sweden)

    Jean-Paul Cheylan

    2007-09-01

    Full Text Available Les approches conjointes de l’espace et du temps, notamment en cartographie animée, supposent un ré examen de quelques notions et concepts mobilisés. Trois concepts, vie, mouvement et généalogie, sont proposés et explicités. Les requêtes susceptibles d'être adressées aux bases de données spatio-temporelles sont abordées à l’aide d’une proposition de classification. Sont enfin explorées quelques problèmes, pistes et exemples de représentations animées conjointes du temps et de l’espace, illustrant les principaux concepts abordés.

  11. Determinação dos multiplicadores da matriz de contabilidade social, da indústria de base florestal paranaense - 1998

    Directory of Open Access Journals (Sweden)

    Ricardo Kureski

    2006-12-01

    Full Text Available Este artigo tem como objetivo mensurar o impacto do aumento da demanda final da indústria de base florestal. Como instrumento de análise utiliza-se a matriz de contabilidade social do Estado do Paraná de 1998. Foi necessário calcular o multiplicares da matriz. Os efeitos de uma injeção nas variáveis exógenas sobre os segmentos de Madeira e Mobiliário e de Papel e Papelão resultaram em choques de demanda mais intensos dentro do próprio setor. Observa-se que o ramo de Madeira e Mobiliário tem maiores ligações com as atividades relativas ao setor terciário; já o segmento de Papel e Papelão, com atividades que necessitam embalagem. Conclui-se que, apesar da agregação das atividades econômicas da matriz de contabilidade social paranaense, foi possível identificar os principais impactos decorrentes do aumento da demanda final.The present article aims at measuring the final demand impact on the forest-based industry by using the 1998 State of Paraná social accounting matrix as the analysis tool. We also had to calculate the matrix multipliers. The increased effects of exogenous activity on the Wood/Furniture and Paper/Pulp activities brought a more intense demand shock to that sector. We noticed that the Wood and Furniture activity is mostly connected with the tertiary sector activities, while the Paper and Pulp activity is mostly connected with activities that need packing. Finally, we could identify the main impacts originated by an increased final demand in spite of the reduction in the number of Paraná Social Accounting Matrix economic activities.

  12. Adrien Dubois, La violence des femmes en Normandie à la fin du Moyen Âge, Société parisienne d’histoire et d’archéologie normandes, coll. Cahiers Léopole Delisle, 2005-2006, Paris, 2010, 400 p.

    Directory of Open Access Journals (Sweden)

    Bernard Dauven

    2012-05-01

    Full Text Available Le but premier de l’ouvrage d’Adrien Dubois, spécialiste de l’histoire de la justice, est de montrer la réalité de violences féminines au Moyen Âge. L’auteur y parvient sans difficulté, ce qui fait de son livre une réussite. Ces violences peuvent dans certains cas être perçues comme légitimes et ne sont pas nécessairement considérées comme « anormales » par les hommes qui rédigent les sources mobilisées par l’auteur. Des femmes, présentes dans l’espace public, frappent, insultent et menacent ...

  13. Présentation du dossier

    Directory of Open Access Journals (Sweden)

    2007-02-01

    Full Text Available Les textes rassemblés dans ce dossier proviennent de la première Journée d’étude organisée par le groupe COnTEXTES, le 28 mars 2006 à l’Université de Liège. Le choix d’aborder une telle problématique a été guidé par le constat d’un décalage générationnel : tandis que la critique idéologique a mobilisé la plupart des consciences théoriques attentives aux forces sociales qui traversent le littéraire (Louis Althusser, Marc Angenot, Philippe Hamon, parmi d’autres, le concept d’idéologie semble a...

  14. Compte rendu de Viala (Alain, La France galante. Essai historique sur une catégorie culturelle, de ses origines jusqu’à la révolution, Paris, PUF, coll. « Les Littéraires », 2008, 541 p.

    Directory of Open Access Journals (Sweden)

    Alexandre De Craim

    2009-08-01

    Full Text Available Alain Viala, professeur à l’Université d’Oxford, a constaté que le concept de galanterie est souvent mobilisé lorsqu’il s’agit d’évoquer la France ou les Français. Cette association d’idée l’a alors conduit à étudier, au-delà du lieu commun, comment un certain modèle galant s’est construit, a prospéré et enfin a décliné tout au long des xviie et xviiie siècles. Pour y parvenir, l’auteur se propose une méthode : l’exploration des œuvres picturales, musicales et littéraires revendiquées comme g...

  15. La Necropoli de Misincinis Tavagnacco

    OpenAIRE

    Le Carlier de Veslud, Cécile

    2011-01-01

    Cette publication est consacrée à l’étude de l’importante nécropole à incinération de Misincinis, située à proximité du village de Paularo, dans la vallée du Chiarso qui entaille les premiers contreforts des Alpes friulanes au nord-est de la plaine du Pô. Datée de l’âge du Fer, elle présente la précieuse particularité d’avoir été entièrement fouillée et d’avoir suscité de nombreuses études sur son mobilier et son environnement. L’ouvrage présenté ici est constitué de trois volumes, le premier...

  16. 2011 : Année internationale de la chimie

    OpenAIRE

    2011-01-01

    Lors de la 63e assemblée générale des Nations Unies, 2011 a été proclamée année internationale de la chimie. En France, les acteurs de la chimie sont mobilisés pour promouvoir quatre objectifs : mettre l’accent sur l’importance de la chimie pour un développement durable dans tous les aspects de la vie sur la planète ; accroître chez les jeunes l’intérêt pour la chimie ; susciter l’enthousiasme pour une chimie tournée vers l’avenir ; célébrer les travaux de Marie Curie et la contribution des f...

  17. Un établissement du début du premier âge du Fer en Eure-et-Loir : Sours, Les Ouches A settlement from the first Iron Age in Eure-et-Loir: Sours, Les Ouches

    Directory of Open Access Journals (Sweden)

    Frédéric Dupont

    2012-01-01

    Full Text Available La fouille du site des Ouches à Sours (28 a permis la mise au jour d’une importante occupation du Néolithique ancien et la découverte, dans la partie nord de l’emprise, de plusieurs structures datables du début de l’âge du Fer (Hallstatt C. Elles correspondent à des structures domestiques (un bâtiment et des fosses et à une entité “ cultuelle ”: un double enclos en “ U ”.L’habitation et ses annexes sont représentées par un bâtiment de plan quadrangulaire sur poteaux et une grande fosse riche en mobilier (céramiques, ossements et silex taillés. Cette structure peut être associée au fonctionnement d’un four de type “ polynésien ” et avoir servi de fosse de rejet.Le double enclos, ouvert vers le nord, est localisé au nord-est du site.Même si trois céramiques entières ont été trouvées dans son fossé externe, l’essentiel du mobilier céramique (177 individus sur 192 est issu de la grande fosse. Il s’agit principalement de coupes, de jattes parfois incisées, de petits gobelets à panse globulaire typiques du Hallstatt C ou de vases servant au stockage. Ils sont dotés de manière régulière de cordons digités.Ce petit établissement du début de l’âge du Fer a livré un bon échantillon des céramiques en usage en Eure-et-Loir à cette époque ainsi que des vestiges archéozoologiques et lithiques en quantité intéressante. Ces découvertes donnent de nouvelles informations sur les affinités culturelles à la transition entre l’âge du Bronze et l’âge du Fer, période peu documentée dans le Nord de la région Centre.The excavation of the site of Ouches at Sours (28 has enabled the updating of an important settlement from the early Neolithic and the discovery, in the northern part of the site, of several structures datable to the beginning of the Iron Age (Hallstatt C. They correspond to domestic structures (a building and some ditches and a “worship” entity: a double

  18. Description of Pseudingolfiella possessionis n. sp. (Crustacea, Amphipoda) from sub-Antarctic Île de La Possession, Crozet archipelago: the second freshwater amphipod known from the Antarctic biome, a human introduction of Gondwanan ancestry?

    Science.gov (United States)

    Smet, Willem H De

    2015-03-31

    A new species of freshwater amphipod, Pseudingolfiella possessionis n. sp. (Senticaudata, Pseudingolfiellidae), is described from the submerged moss vegetation of small brooklets at sub-Antarctic Île de La Possession, Crozet archipelago. It constitutes the second freshwater amphipod species known for the sub-Antarctic and Antarctic region, and the fourth member of the genus. The main characters distinguishing it from all congeners are: the spine on the posterior margin of the dactylus, incisor and lamina mobilis of mandible each with 5 teeth, the setation of the maxilliped, the vestigial second article of pleopod 3 in the female, the undulate and laterally notched posterolateral margin of the external ramus of uropods 1 and 2 in the male, the spinulate dorsomedian projection of the telson.

  19. O que o skate pode dizer sobre o ensino de geografia?

    Directory of Open Access Journals (Sweden)

    Luciano Hermes da Silva

    2014-07-01

    Full Text Available Este artigo pretende problematizar a prática do skate de rua como objeto de reflexão no âmbito do ensino de Geografia. Objetiva demonstrar como os skatistas protagonizam a ressignificação da cidade através de usos originais do mobiliário urbano. Trata-se de reforçar o movimento que articula as práticas espaciais dos jovens aos conteúdos e temas tradicionais da Geografia. A partir da referência ao conceito de espaço público, busca-se demonstrar que o recurso às práticas cotidianas da juventude permite problematizar conflitos, relações identitárias e processos relacionados à produção social do espaço.

  20. Usages des technologies par les élèves professeurs : analyse à partir de questionnaires

    Directory of Open Access Journals (Sweden)

    Philippe Le Borgne

    2005-01-01

    Full Text Available Cet article étudie l’appropriation et les usages des technologies chez les élèves professeurs français. La méthodologie utilisée est basée sur l’analyse de réponses à des questionnaires soumis aux professeurs stagiaires de quatre instituts universitaires de formation des maîtres. Les résultats obtenus tendent à prouver que les enseignants en formation sont aujourd’hui bien équipés et disposent de compétences réelles dans le cadre des usages personnels et professionnels en dehors de la classe. Cependant, il apparaît que ces compétences sont peu mobilisées dans le cadre des usages en classe.

  1. The state of autotrophic ethanol production in Cyanobacteria.

    Science.gov (United States)

    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.

  2. Les objets mobiliers des XIXe et XXe siècles : les sources

    OpenAIRE

    Finance, Laurence de

    2012-01-01

    L’étude scientifique de tout objet ne peut se concevoir sans une recherche dans les sources documentaires. Qu’il s’agisse d’archives publiques ou privées, de legs faits à des musées ou autres institutions patrimoniales, la quête de renseignements est une nécessité pour suivre l’objet étudié depuis sa création jusqu’à son étude faite in Situ. De nos jours, de nombreuses ressources sont mises en ligne, notamment sur le site du ministère de la culture et de la communication ; accessibles à tous,...

  3. Vers une agroécologie biodiverse : enjeux et principaux concepts mobilisés

    OpenAIRE

    Reboud , Xavier; MALEZIEUX , Eric

    2015-01-01

    SPEPôle ECOLDUR; This text relates to the introduction of the workshop “Using biodiversity” given on October, 18th at the 2013 symposium on Agroecology. It is inspired by the discussions of the working group "Agroecology and soil" of the alliance between institutes on environmental research AllEnvi. Some major issues are exposed and the principles on how the use of biodiversity could improve agroecosystem management are presented.; Ce texte constitue l’introduction à l’atelier « utiliser la B...

  4. Structure-soil-structure interaction of nuclear structures

    International Nuclear Information System (INIS)

    Snyder, M.D.; Shaw, D.E.; Hall, J.R. Jr.

    1975-01-01

    Structure-to-structure interaction resulting from coupling of the foundations through the soil has traditionally been neglected in the seismic analysis of nuclear power plants. This paper examines the phenomenon and available methods of analytical treatment, including finite element and lumped parameter methods. Finite element techniques have lead to the treatment of through soil coupling of structural foundations using two dimensional plane strain models owing to the difficulty of considering three dimensional finite element models. The coupling problem is treated by means of a lumped parameter model derived from elastic half-space considerations. Consequently, the method is applicable to the interaction of any number of foundations and allows the simultaneous application of tri-directional excitation. The method entails the idealization of interacting structures as lumped mass/shear beams with lumped soil springs and dampers beneath each foundation plus a coupling matrix between the interacting foundations. Utilizing classical elastic half-space methods, the individual foundation soil springs and dampers may be derived, accounting for the effects of embedment and soil layering, analogous to the methods used for single soil-structure, interaction problems. The coupling matrix is derived by generating influence coefficients based on the geometric relationship of the structures using classical half-space solutions. The influence coefficients form the coupling flexibility matrix which is inverted to yield the coupling matrix for the lumped parameter model

  5. Fluid-structure interaction of submerged structures

    International Nuclear Information System (INIS)

    Tang, H.T.; Becker, E.B.; Taylor, L.M.

    1979-01-01

    The purpose of the paper is to investigate fluid-structure interaction (FSI) of submerged structures in a confined fluid-structure system. Our particular interest is the load experienced by a rigid submerged structure subject to a pressure excitation in a fluid domain bounded by a structure which is either flexible or rigid. The objective is to see whether the load experienced by the submerged structure will be influenced by its confinement conditions. This investigation is intended to provide insight into the characteristics of FSI and answer the question as to whether one can obtain FSI independent data by constructing a small scale rigid submerged structure inside a flexible fluid-structure system. (orig.)

  6. Computational structural mechanics for engine structures

    Science.gov (United States)

    Chamis, C. C.

    1989-01-01

    The computational structural mechanics (CSM) program at Lewis encompasses: (1) fundamental aspects for formulating and solving structural mechanics problems, and (2) development of integrated software systems to computationally simulate the performance/durability/life of engine structures. It is structured to mainly supplement, complement, and whenever possible replace, costly experimental efforts which are unavoidable during engineering research and development programs. Specific objectives include: investigate unique advantages of parallel and multiprocesses for: reformulating/solving structural mechanics and formulating/solving multidisciplinary mechanics and develop integrated structural system computational simulators for: predicting structural performances, evaluating newly developed methods, and for identifying and prioritizing improved/missing methods needed. Herein the CSM program is summarized with emphasis on the Engine Structures Computational Simulator (ESCS). Typical results obtained using ESCS are described to illustrate its versatility.

  7. Il servizio di EV-mobile ed i suoi utenti: un approccio metodologico all’analisi dei loro comportamenti

    Directory of Open Access Journals (Sweden)

    Ugo Contino

    2012-07-01

    Full Text Available ItLa possibilità di accedere al Web mediante dispositivi mobili, ad esempio tablet o smartphone, ha comportato la creazione di ulteriori portali, semplificati, che consentono di diffondere contenuti ed informazione in maniera rapida ai propri utenti. Nel caso del servizio di Emeroteca Virtuale Mobile si è voluto ampliare la gamma dei servizi offerti all’utenza, includendo una piattaforma che fosse navigabile attraverso i browser disponibili nei moderni smart phone. L’analisi dei loro comportamenti ci ha permesso di verificare quanto gli utenti preferiscano i contesti mobili come ambienti di rapida verifica delle novità disponibili in Emeroteca, relativamente ai periodici di loro interesse (4 a 1 è infatti il rapporto tra la navigazione e la ricerca dei contenuti. Ciò chiarisce il ruolo che tale servizio sta assumendo nel contesto dell’Emeroteca, non alternativo a quello classico, ma, pur se ancora non privo di una sua connotazione sperimentale, certamente complementare a quest’ultimo.EnThe diffusion of the so called smart-phone and tablet among WEB users community caused a growth in the offering of specific portals, simplified comparing to the classic ones, but capable of a more direct and fast information flow towards their own users. Emeroteca Virtuale service too has been provided of a specific “mobile” portal dedicated to people having a smart-phone as a web access tool. Last two years usage data analysis on this service has revealed a peculiar behavior of Emeroteca Virtuale Mobile users: they tend to use the service as a rapid check of new entries in Emeroteca (issues or articles, specifically for those e-journals they are interested in (the ratio between browsing and search actions is 4 to 1. This clarifies better the role this “mobile” service is having versus the classical one: it is not an alternative to it, but a complementary way to get information from Emeroteca.

  8. App per l’infanzia: linee guida per una progettazione efficace

    Directory of Open Access Journals (Sweden)

    Silvia Carbotti

    2015-04-01

    Full Text Available I bambini sono affascinati dai tablet e dai dispositivi mobili di ultima generazione. Allo stesso modo si trovano in una fase della vita in cui iniziano a formare preferenze e competenze così come ad esprimere le proprie emozioni e sensazioni attraverso la parola. Questo articolo descrive le strategie per la creazione di applicazioni (app per bambini che siano non solo divertenti ma anche efficaci per esperienze significative che li coinvolgano a livello cognitivo ed emotivo. Quando si disegnano app rivolte ai bambini occorre ricordare che i più piccoli non hanno ancora chiaro come dovrebbe funzionare una specifica tecnologia ma si stanno formando un’opinione a riguardo. Diventa dunque necessario considerare alcuni principi di interaction e visual design affinché l’esperienza vissuta con il tablet incontri bisogni e competenze.

  9. Influence of Iron on Production of the Antibacterial Compound Tropodithietic Acid and Its Noninhibitory Analog in Phaeobacter inhibens

    DEFF Research Database (Denmark)

    D'Alvise, Paul W; Phippen, Christopher B W; Nielsen, Kristian Fog

    2016-01-01

    production is influenced by substrate components. High concentrations of ferric citrate, as present in marine broth, or other iron sources were required for production of antibacterially active TDA. However, when supernatants of noninhibitory, low-iron cultures of Phaeobacter inhibens were acidified......Tropodithietic acid (TDA) is an antibacterial compound produced by some Phaeobacter and Ruegeria spp. of the Roseobacter clade. TDA production is studied in marine broth or agar since antibacterial activity in other media is not observed. The purpose of this study was to determine how TDA......, antibacterial activity was detected in a bioassay. The absence of TDA in nonacidified cultures and the presence of TDA in acidified cultures were verified by liquid chromatography-high-resolution mass spectrometry. A noninhibitory TDA analog (pre-TDA) was produced by P. inhibens, Ruegeria mobilis F1926...

  10. La nécropole mérovingienne d’Erstein (Bas-Rhin) : étude des textiles minéralisés au contact des fibules

    OpenAIRE

    Médard, Fabienne; Rohmer, Pascal; Moulherat, Christophe; Guillaume, Jacques

    2008-01-01

    Au cours des années 1999 et 2000, des fouilles de sauvetage ont été menées au lieu dit « Beim Limersheimerweg », non loin de la ville d’Erstein (France, Bas-Rhin). Une importante nécropole datée entre le début du VIe et la fin du VIIe siècle après J.-C. a été mise au jour. 239 sépultures au mobilier funéraire très riche ont été découvertes. Alors que les matières organiques d’origine végétale et animale ont été peu préservées, les nombreuses pièces d’armement (épées longues, scramasaxes, cout...

  11. Interfon

    CERN Multimedia

    Interfon

    2014-01-01

      www.interfon.fr Rendez-vous sur notre site pour toutes les « News » Interfon « Partenaires "confiance" chez Interfon » Nouveau partenaire  « Design Cuisines» Total home design « Nouveau »     « 5 % de remise aux sociétaires »   Découvrez vite cette nouvelle adresse qui donne des Ailes à vos envies de design ! Jean Marc Iglesias n’est pas un concepteur de cuisines comme les autres. Loin des standards d’implantation, il vous propose une approche globale de votre espace de vie et répond à vos besoins et attentes par un projet au design unique et sur-mesure. Iglesias Design c’est aussi des agencements de dressing, salle de bains, chambres, mobilier de salon…         &am...

  12. Organisational StructureStructures for Growth

    OpenAIRE

    Ramskill, Jason

    2011-01-01

    Summary Rexam Plc has articulated that part of the company’s strategy is to make a carefully managed expansion into the emerging markets. In this report I suggest an alternative structure for Rexam to enable implementation of such a strategy and propose a business process for designing effective organisational structures. The work of Chandler (1962) charts the evolution of company organisational structures from the early centralised structures of the 1920s to the multidivisional str...

  13. Structural optimization of free-form reciprocal structures

    DEFF Research Database (Denmark)

    Parigi, Dario

    2014-01-01

    This paper presents an optimization algorithm for the design of structurally efficient free-form reciprocal structures. Because of the geometric complexity of reciprocal structures, only a few structural studies have been carried out so far, and we have a limited knowledge of the relation between...

  14. Motivy narození Páně na lidovém mobiliáři

    Czech Academy of Sciences Publication Activity Database

    Kafka, Luboš

    2016-01-01

    Roč. 11, č. 55 (2016), s. 8-11 ISSN 2336-8667 Institutional support: RVO:68378076 Keywords : visual folk art * Nativity * Jesus Christus * folk furniture * museum collections Subject RIV: AC - Archeology, Anthropology, Ethnology

  15. Les Horologia romana en Hispanie, mobilier, histoire et realités archéologiques

    Directory of Open Access Journals (Sweden)

    Bonnin, Jerome

    2010-12-01

    Full Text Available There has been no previous global study of the Horologia in Hispania. The purpose of the present study is to collect together current knowledge with archaeological discoveries as well as iconographical or epigraphical one. The archaeological remains, most often under-exploited, reveal a clear predominance of objects discovered in private contexts and a local production in most cases. Nevertheless, the existence of sundials in public centres is also attested not only by the epigraphy, well known, but also by the archaeological discoveries. Finally the opportunity is taken to review the available information about the so-called ‘sundial’ from Yecla with its unusual design. Although not discussed recently its use as a sundial is still open to question.El estudio de los Horologia romana en Hispania no ha sido hecho hasta ahora. Este es el propósito del presente artículo que constituye al mismo tiempo una síntesis de los conocimientos existentes sobre este aspecto de la civilización romana en Hispania y un catálogo y estudio de toda la evidencia arqueológica, iconográfica y epigráfica. Los restos arqueológicos, en ocasiones poco estudiados por los descubridores, revelan un claro predominio de objetos descubiertos en ámbitos privados y una producción local en muchos casos. No obstante, la existencia de relojes en centros públicos está atestiguada no sólo por la epigrafía, bien conocida, sino también por los descubrimientos arqueológicos. Finalmente, el artículo brinda la oportunidad de redescubrir el llamado reloj de Yecla, de una iconografía totalmente inusual, prácticamente olvidado por los investigadores, pero que todavía hoy está sometido a discusión.

  16. Structural cladding /clad structures

    DEFF Research Database (Denmark)

    Beim, Anne

    2012-01-01

    Structural Cladding /Clad Structures: Studies in Tectonic Building Practice A. Beim CINARK – Centre for Industrialized Architecture, Institute of Architectural Technology, The Royal Danish Academy of Fine Arts School of Architecture, Copenhagen, Denmark ABSTRACT: With point of departure in the pr......Structural Cladding /Clad Structures: Studies in Tectonic Building Practice A. Beim CINARK – Centre for Industrialized Architecture, Institute of Architectural Technology, The Royal Danish Academy of Fine Arts School of Architecture, Copenhagen, Denmark ABSTRACT: With point of departure...... to analyze, compare, and discuss how these various construction solutions point out strategies for development based on fundamentally different mindsets. The research questions address the following issues: How to learn from traditional construction principles: When do we see limitations of tectonic maneuver......, to ask for more restrictive building codes. As an example, in Denmark there are series of increasing demands in the current building legislations that are focused at enhancing the energy performance of buildings, which consequently foster rigid insulation standards and ask for improvement of air...

  17. Study on structural integrity in box structures

    International Nuclear Information System (INIS)

    Asano, Masayuki; Ueta, Masahiro; Kanaoka, Tadashi; Ikeuchi, Toshiaki; Kodama, Tetsuhiro.

    1991-01-01

    This study was carried out to give an experimental foundation to the structural integrity of a box structure. Crack growth tests were performed on the reduced scale models, simulating typical portions of the box structure, in air at room temperature. The results show that the amount of crack growth is too small to injure the structural integrity of the models for the postulated loading cycle, and make clear the effective structure against crack growth. (author)

  18. Prosodic structure as a parallel to musical structure

    Directory of Open Access Journals (Sweden)

    Christopher Cullen Heffner

    2015-12-01

    Full Text Available What structural properties do language and music share? Although early speculation identified a wide variety of possibilities, the literature has largely focused on the parallels between musical structure and syntactic structure. Here, we argue that parallels between musical structure and prosodic structure deserve more attention. We review the evidence for a link between musical and prosodic structure and find it to be strong. In fact, certain elements of prosodic structure may provide a parsimonious comparison with musical structure without sacrificing empirical findings related to the parallels between language and music. We then develop several predictions related to such a hypothesis.

  19. Interfon

    CERN Multimedia

    Interfon

    2012-01-01

    www.interfon.fr Rendez-vous sur notre site internet pour découvrir toutes les informations « Nouveaux Partenaires » « EuroCave » situé à Gland, fournit des prestations en France et en Suisse. Solutions pour la mise en valeur & le service du vin (Caves et armoires à vins, systèmes de rangement, création et climatiseurs de cave), mais aussi Cave à cigares et billards. Présentez votre carte de sociétaire et tout au long de l’année, bénéficiez (hors soldes et promotions) de : 15 % sur les caves à vins et à cigares. 20 % sur les travaux de conception et d’aménagement de cave " sur mesure " (mobilier et climatisation …). 10 % sur les billards. 10  % sur les cheminées éthanol (ecosma...

  20. A personalised and adaptive intelligent system to adjust circadian lighting for elderly housing

    DEFF Research Database (Denmark)

    Flyvholm, Anton; Sen, Sumit; Xylakis, Emmanouil

    2016-01-01

    With the rapid population ageing in Europe and in Denmark, there is an increasing interest in technologies and designs that can support the elderly citizens in sustaining well-being and health along with preventing functional decline [1]. To date, the designs of lighting systems in elderly housing...... detection, actigraphy, etc.) and c) anthropological (mood and behaviour). This way, the effect of circadian lighting on well-being, can be also documented, before this new technology can be recommended for implementation in elderly housing. A test installation is planned at “Sundhedshuset” in Albertslund...... places, nursing homes, domestic applications, and smart cities. Accelerate SSL - Innovation for Europe. SSL-Erate. Available from: http://lightingforpeople.eu/2016/wp-content/uploads/2016/03/SSLerate-3.2-3.4-v4.pdf. [3] Mobily PR, Skemp Kelley LS. (1991). Iatrogenesis in the elderly. Factors...

  1. Vibration-based structural health monitoring of harbor caisson structure

    Science.gov (United States)

    Lee, So-Young; Lee, So-Ra; Kim, Jeong-Tae

    2011-04-01

    This study presents vibration-based structural health monitoring method in foundation-structure interface of harbor caisson structure. In order to achieve the objective, the following approaches are implemented. Firstly, vibration-based response analysis method is selected and structural health monitoring (SHM) technique is designed for harbor caisson structure. Secondly, the performance of designed SHM technique for harbor structure is examined by FE analysis. Finally, the applicability of designed SHM technique for harbor structure is evaluated by dynamic tests on a lab-scaled caisson structure.

  2. Structural Behaviour of Reciprocal Structures

    DEFF Research Database (Denmark)

    Parigi, Dario; Kirkegaard, Poul Henning

    2013-01-01

    The present paper focuses on the comparison of several two-dimensional and three-dimensional reciprocal configurations. The goal of such comparison is to analyse the structural behaviour when changing the geometric parameters used to describe the geometry of reciprocal structures....

  3. Correlating Structural Order with Structural Rearrangement in Dusty Plasma Liquids: Can Structural Rearrangement be Predicted by Static Structural Information?

    Science.gov (United States)

    Su, Yen-Shuo; Liu, Yu-Hsuan; I, Lin

    2012-11-01

    Whether the static microstructural order information is strongly correlated with the subsequent structural rearrangement (SR) and their predicting power for SR are investigated experimentally in the quenched dusty plasma liquid with microheterogeneities. The poor local structural order is found to be a good alarm to identify the soft spot and predict the short term SR. For the site with good structural order, the persistent time for sustaining the structural memory until SR has a large mean value but a broad distribution. The deviation of the local structural order from that averaged over nearest neighbors serves as a good second alarm to further sort out the short time SR sites. It has the similar sorting power to that using the temporal fluctuation of the local structural order over a small time interval.

  4. Significance of structure–soil–structure interaction for closely spaced structures

    International Nuclear Information System (INIS)

    Roy, Christine; Bolourchi, Said; Eggers, Daniel

    2015-01-01

    Nuclear facilities typically consist of many closely spaced structures with different sizes and depths of embedment. Seismic response of each structure could be influenced by dynamic structure–soil–structure interaction (SSSI) behavior of adjacent closely spaced structures. This paper examines the impact of SSSI on the in-structure response spectra (ISRS) and peak accelerations of a light structure adjacent to a heavy structure and of a heavy structure adjacent to a similar heavy structure for several soil cases, foundation embedment depths, and separation distances. The impacts of a heavy surface or embedded structure on adjacent ground motions were studied. The analyses demonstrated the adjacent ground motions are sensitive to foundation embedment, soil profile, response frequency, and distance from the structure. Seismic responses of a light structure located near a heavy structure are calculated either by modeling both structures subjected to free field motions, or performing a cascade analysis by considering the light structure model subjected to modified ground motions due to the heavy structure. Cascade SSSI analyses are shown to adequately account for the effect of the heavy structure on the light structure without explicitly modeling both structures together in a single analysis. To further study the influence of SSSI behavior, this paper examines dynamic response of two adjacent heavy structures and compares this response to response of a single heavy structure neglecting adjacent structures. The SSSI responses of the two heavy structures are evaluated for varying soil conditions and structure separation distances using three-dimensional linear SSI analyses and considering anti-symmetry boundary conditions. The analyses demonstrate that the SSSI response of a light or a heavy structure can be influenced by the presence of a nearby heavy structure. Although this study considers linear analysis methodology, the conclusion of SSSI influences on dynamic

  5. Structural health monitoring for ship structures

    Energy Technology Data Exchange (ETDEWEB)

    Farrar, Charles [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Angel, Marian [Los Alamos National Laboratory; Bement, Matthew [Los Alamos National Laboratory; Salvino, Liming [NSWC, CADEROCK

    2009-01-01

    Currently the Office of Naval Research is supporting the development of structural health monitoring (SHM) technology for U.S. Navy ship structures. This application is particularly challenging because of the physical size of these structures, the widely varying and often extreme operational and environmental conditions associated with these ships missions, lack of data from known damage conditions, limited sensing that was not designed specifically for SHM, and the management of the vast amounts of data that can be collected during a mission. This paper will first define a statistical pattern recognition paradigm for SHM by describing the four steps of (1) Operational Evaluation, (2) Data Acquisition, (3) Feature Extraction, and (4) Statistical Classification of Features as they apply to ship structures. Note that inherent in the last three steps of this process are additional tasks of data cleansing, compression, normalization and fusion. The presentation will discuss ship structure SHM challenges in the context of applying various SHM approaches to sea trials data measured on an aluminum multi-hull high-speed ship, the HSV-2 Swift. To conclude, the paper will discuss several outstanding issues that need to be addressed before SHM can make the transition from a research topic to actual field applications on ship structures and suggest approaches for addressing these issues.

  6. Influência do assento da cadeira adaptada na execução de uma tarefa de manuseio Influence of the seat surface of an adapted chair on the performance of a manipulation task

    Directory of Open Access Journals (Sweden)

    Lígia Maria Presumido Braccialli

    2008-04-01

    Full Text Available Este estudo teve como objetivo verificar a influência da flexibilidade da superfície de assento da cadeira na velocidade e no tempo despendido por alunos com paralisia cerebral espástica durante a execução de uma tarefa de manuseio de um objeto na posição sentada. Participaram do estudo 11 alunos, de ambos os gêneros, com diagnóstico de paralisia cerebral espástica, que tinham algum controle de tronco e membros superiores. A quantificação da análise cinemática foi realizada em duas situações experimentais: 1 execução de uma tarefa acadêmica de encaixe, com o indivíduo posicionado em um mobiliário adaptado com assento de lona; 2 execução de uma tarefa acadêmica de encaixe, com o participante posicionado em um mobiliário adaptado com assento de madeira. Os dados obtidos foram submetidos à análise estatística descritiva e não-paramétrica por meio do teste de Wilcoxon. Os resultados indicaram que: 1 a velocidade média de execução das tarefas não foi influenciada pelo tipo de assento utilizado 2 o tempo de execução da tarefa foi influenciada pelo tipo de assento utilizado. A utilização do assento de lona aumentou o tempo de realização da tarefa. Conclui-se que o assento de um mobiliário escolar para um aluno com paralisia cerebral espástica não deve ser confeccionado com um material muito flexível. Este tipo de assento fornecerá uma base instável que dificultará o desempenho do aluno durante atividades realizadas com os membros superiores.The objective of this study was to verify the influence of the flexibility of the seat surface of a chair on the speed and time expended by students with spastic cerebral palsy during the performance of a task involving the manipulation an object while in a seated position. Eleven students of both genders participated in the study; all were diagnosed with spastic cerebral palsy, and all had some control of trunk and upper limbs. The quantification of the kinematics

  7. Histoire, mémoire et tribus ou les aarch de 2001 en Kabylie

    Directory of Open Access Journals (Sweden)

    Nassim Amrouche

    2011-03-01

    Full Text Available Les émeutes qui ont ensanglanté la Kabylie au cours du printemps 2001 ont soulevé différentes problématiques. Au-delà du drame humain qui a fait plus d’une centaine de morts et plus d’un millier de blessés, cette contestation s’est formulée autour d’une organisation anachronique : les aarch. Système sociopolitique ancien dont les dernières traces d’existence remontent à la fin du XIXe siècle, il a mobilisé dans et par la tribu reconfigurée selon les besoins contemporains. Cette utilisation d’une organisation sociale maghrébine a permis de une inscription dans le temps par la mémoire mobilisée par la tribu.En effet, dans une perspective politique, les aarch, pour contester le présent, ont mis en exergue des patrimoines historiques et mémoriels effacés par l’État nation algérien. Mobilisant ainsi l’histoire de la guerre de décolonisation, fondatrice de l’État indépendant, les aarch se sont directement attaqués au vouloir vivre ensemble, redéfinissant les bases constitutives de la nation. Cette dynamique mémorielle et historique a aussi permis aux militants et partisans de revisiter un passé plus lointain : crises au sein du mouvement nationaliste, mouvements sociaux post Indépendance, etc. Ce remaniement des mémoires, dont la culture et la langue restent les socles, a permis d’envisager des territoires culturels, identitaires dépassant les frontières stato-nationales.Si ces données sont celles du politique, des militants, les bases sociales du mouvement, qui a mobilisé jusqu’à 1,5 million de personnes, ont réutilisé ces outils de la contestation pour les transformer en sources du malaise socioéconomique contemporain.The riots that have bloodstained Kabylie in the spring of 2001 have raised different problematics. Beyond the human drama which has resulted in more than a hundred deaths and a thousand wounded, this contestation formulated itself around an anachronic organization: the

  8. Structural priority approach to fluid-structure interaction problems

    International Nuclear Information System (INIS)

    Au-Yang, M.K.; Galford, J.E.

    1981-01-01

    In a large class of dynamic problems occurring in nuclear reactor safety analysis, the forcing function is derived from the fluid enclosed within the structure itself. Since the structural displacement depends on the fluid pressure, which in turn depends on the structural boundaries, a rigorous approach to this class of problems involves simultaneous solution of the coupled fluid mechanics and structural dynamics equations with the structural response and the fluid pressure as unknowns. This paper offers an alternate approach to the foregoing problems. 8 refs

  9. Structure soil structure interaction effects: Seismic analysis of safety related collocated concrete structures

    International Nuclear Information System (INIS)

    Joshi, J.R.

    2000-01-01

    The Process, Purification and Stack Buildings are collocated safety related concrete shear wall structures with plan dimensions in excess of 100 feet. An important aspect of their seismic analysis was the determination of structure soil structure interaction (SSSI) effects, if any. The SSSI analysis of the Process Building, with one other building at a time, was performed with the SASSI computer code for up to 50 frequencies. Each combined model had about 1500 interaction nodes. Results of the SSSI analysis were compared with those from soil structure interaction (SSI) analysis of the individual buildings, done with ABAQUS and SASSI codes, for three parameters: peak accelerations, seismic forces and the in-structure floor response spectra (FRS). The results may be of wider interest due to the model size and the potential applicability to other deep soil layered sites. Results obtained from the ABAQUS analysis were consistently higher, as expected, than those from the SSI and SSSI analyses using the SASSI. The SSSI effect between the Process and Purification Buildings was not significant. The Process and Stack Building results demonstrated that under certain conditions a massive structure can have an observable effect on the seismic response of a smaller and less stiff structure

  10. An impedance function approach for soil-structure interaction analyses including structure-to-structure interaction effects

    International Nuclear Information System (INIS)

    Gantayat, A.; Kamil, H.

    1981-01-01

    The dynamic soil-structure and structure-to-structure interaction effects may be determined in one of the two ways: by modeling the entire soil-structure system by a finite-element model, or by using a frequency-dependent (or frequency-independent) impedance function approach. In seismic design of nuclear power plant structures, the normal practice is to use the first approach because of its simplicity and easy availability of computer codes to perform such analyses. However, in the finite-element approach, because of the size and cost restrictions, the three-dimensional behavior of the entire soil-structure system and the radiation damping in soil are only approximately included by using a two-dimensional finite-element mesh. In using the impedance function approach, the soil-structure analyses can be performed in four steps: (a) determination of the dynamic properties of the fixed base superstructure, (b) determination of foundation and structure impedance matrices and input motions, (c) evaluation of foundation motion, (d) analysis of the fixed base superstructure using computed foundation motion. (orig./RW)

  11. Cooling pipeline disposing structure for large-scaled cryogenic structure

    International Nuclear Information System (INIS)

    Takahashi, Hiroyuki.

    1996-01-01

    The present invention concerns an electromagnetic force supporting structure for superconductive coils. As the size of a cryogenic structure is increased, since it takes much cooling time, temperature difference between cooling pipelines and the cryogenic structure is increased over a wide range, and difference of heat shrinkage is increased to increase thermal stresses. Then, in the cooling pipelines for a large scaled cryogenic structure, the cooling pipelines and the structure are connected by way of a thin metal plate made of a material having a heat conductivity higher than that of the material of the structure by one digit or more, and the thin metal plate is bent. The displacement between the cryogenic structure and the cooling pipelines caused by heat shrinkage is absorbed by the elongation/shrinkage of the bent structure of the thin metal plate, and the thermal stresses due to the displacement is reduced. In addition, the heat of the cryogenic structures is transferred by way of the thin metal plate. Then, the cooling pipelines can be secured to the cryogenic structure such that cooling by heat transfer is enabled by absorbing a great deviation or three dimensional displacement due to the difference of the temperature distribution between the cryogenic structure enlarged in the scale and put into the three dimensional shape, and the cooling pipelines. (N.H.)

  12. La sélection des objets à protéger dans les églises de la Reconstruction : l’exemple de la Manche (1944-1974

    Directory of Open Access Journals (Sweden)

    Élisabeth Marie

    2012-04-01

    Full Text Available Plus de trois cents églises de la Manche ont été détruites ou gravement endommagées en 1944. La Reconstruction, étalée sur une trentaine d’années, est devenue une composante du patrimoine départemental. La Conservation des antiquités et objets d’art a entrepris un inventaire de ce patrimoine qui concerne cent soixante édifices et environ cent trente objets, auxquels s’ajoutent les ensembles de vitraux. Dans un premier temps, trente édifices ont été inventoriés, parallèlement à l’étude menée sur les édifices par le service des Monuments historiques de Basse-Normandie. Ces deux enquêtes ont été suivies de mesures de protection concernant quarante objets ou ensembles mobiliers conservés dans les églises de la Manche. Les critères généraux de protection au titre des monuments historiques ont été débattus, affinés et précisés lors de deux commissions départementales des objets mobiliers thématiques.In 1944 more than three hundred churches in the Manche department were destroyed or badly damaged. The reconstruction of these churches took over thirty years, and these reconstructed churches are now recognised as an integral part of the department’s heritage. The services of the Conservation des antiquités et objets d’art has undertaken an inventory of these churches, focussed on 160 buildings and about 130 religious artefacts, along with a collection of stained glass. To begin with, the contents of thirty churches were surveyed in an operation running alongside an inventory of religious buildings carried out by the Historic monuments service of the Basse-Normandie region. These two surveys were followed by measures of statutory protection for forty objects or furnishing ensembles conserved in the department’s churches. There was considerable debate as to the criteria appropriate for the protection of these objects, and two meetings of the departmental commission on the protection of the movable heritage

  13. Atmospheric anthropic impacts tracked by the French atmospheric mobile observatory

    Science.gov (United States)

    Cuesta, J.; Chazette, P.; Flamant, P. H.

    2009-04-01

    A new ATmospheric Mobile ObServatory, so called "ATMOS", has been developed by the LiMAG "Lidar, Meteorology and Geophysics" team of the Institut Pierre Simon Laplace (IPSL) in France, in order to contribute to international field campaigns for studying atmospheric physico-chemistry, air quality and climate (i.e. aerosols, clouds, trace gazes, atmospheric dynamics and energy budget) and the ground-based validation of satellite observations. ATMOS has been deployed in the framework of i) LISAIR, for monitoring air quality in Paris in 2005, ii) AMMA "African Monsoon Multidisciplinary Analysis", in Tamanrasset and in Niamey for observing the aerosols and the atmospheric boundary layer in the Sahara and in the Sahel in 2006, iii) COPS "Convectively and Orographycally driven Precipitation Study" in the Rhin Valley in 2007 and iv) the validation of the spatial mission CALIPSO, launched in April 2006. In the coming years, ATMOS will be deployed i) in the Paris Megacity, in the framework of MEGAPOLI (2009-2010), ii) in southern France (near Marseille) for the Chemistry-Aerosol Mediterranean Experiment CHARMEX (2011-2012) and iii) the validation of ADM-Aeolus in 2010-2011 and Earth-Care in 2012. ATMOS payload is modular, accounting for the different platforms, instruments and measuring techniques. The deployment of ATMOS is an essential contribution to field campaigns, complementing the fixed sites, and a potential alternative of airborne platforms, heavier and more expensive. ATMOS mobile payload comprises both the remote sensing platform MOBILIS ("Moyens mOBIles de téLédetection de l'IPSL") and the in-situ physico-chemical station SAMMO ("Station Aérosols et chiMie MObile"). MOBILIS is an autonomous and high-performance system constituted by a full set of active and passive remote sensing instrumentation (i.e. Lidars and radiometers), whose payload may be adapted for either i) long term fixed monitoring in a maritime container or a shelter, ii) ground-based transect

  14. Soil Retaining Structures : Development of models for structural analysis

    NARCIS (Netherlands)

    Bakker, K.J.

    2000-01-01

    The topic of this thesis is the development of models for the structural analysis of soil retaining structures. The soil retaining structures being looked at are; block revetments, flexible retaining walls and bored tunnels in soft soil. Within this context typical structural behavior of these

  15. Structural biology at York Structural Biology Laboratory; laboratory information management systems for structural genomics

    Czech Academy of Sciences Publication Activity Database

    Dohnálek, Jan

    2005-01-01

    Roč. 12, č. 1 (2005), s. 3 ISSN 1211-5894. [Meeting of Structural Biologists /4./. 10.03.2005-12.03.2005, Nové Hrady] R&D Projects: GA MŠk(CZ) 1K05008 Keywords : structural biology * LIMS * structural genomics Subject RIV: CD - Macromolecular Chemistry

  16. Structuralism, Post-Structuralism, and Neo-Liberalism: Assessing Foucault's Legacy.

    Science.gov (United States)

    Olssen, Mark

    2003-01-01

    Traces Foucault's distinctive commitment to "post-structuralism." Argues that under the influence of Nietzsche, Foucault's approach marks a distinct break with structuralism in several crucial aspects. What results is a materialist post-structuralism that is also distinctively different from the post-structuralism of Derrida, Lyotard,…

  17. Analysis of Pumphouse RCC Frame Structure for Soil Structure Interaction

    OpenAIRE

    Mr A.S. Thombare; Prof. V.P. Kumbhar; Prof. A.H. Kumbhar

    2016-01-01

    When structure is built on ground some elements of structure are direct contact with soil. When loads are applied on structure internal forces are developed in both the structure as well as in soil. It results in deformation of both the components which are independent to each other. This are called soil structure interaction. The analysis is done by using (Bentley STAAD.Pro V8i Version 2007) software. The analysis carried out been pump house structure R.C.C. frame structure find ...

  18. Structural behaviour of super-light structures

    DEFF Research Database (Denmark)

    Bagger, Anne; Hertz, Kristian Dahl

    2010-01-01

    structural functions: it leads load to the skeleton, it stabilizes the compression members of the skeleton, and it redistributes loads that are not optimal for the skeleton shape. In this paper, FE analysis is used to investigated the behaviour of a series of SLS beams of concrete, under varying stiffness......A new structural concept, called Super-light Structures (SLS), has recently been invented and patented at the Technical University of Denmark. The basic concept of SLS is to construct a skeleton of a stiff and strong material, such as ordinary or high strength concrete, and stabilize this skeleton...... with a lighter and softer material, such as lightweight concrete. The combined use of stiff and light material in SLS results in structures of high stiffness and low weight. The applied technology and the advantages of SLS are elaborated upon in [1] in these proceedings. The present paper focuses...

  19. Effects of non-structural components and soil-structure interaction on the seismic response of framed structures

    Science.gov (United States)

    Ditommaso, Rocco; Auletta, Gianluca; Iacovino, Chiara; Nigro, Antonella; Carlo Ponzo, Felice

    2017-04-01

    In this paper, several nonlinear numerical models of reinforced concrete framed structures have been defined in order to evaluate the effects of non-structural elements and soil-structure interaction on the elastic dynamic behaviour of buildings. In the last few years, many and various studies have highlighted the significant effects derived from the interaction between structural and non-structural components on the main dynamic characteristics of a building. Usually, structural and non-structural elements act together, adding both masses and stiffness. The presence of infill panels is generally neglected in the design process of structural elements, although these elements can significantly increase the lateral stiffness of a structure leading to a modification in the dynamic properties. Particularly, at the Damage Limit State (where an elastic behaviour is expected), soil-structure interaction effects and non-structural elements may further affect the elastic natural period of buildings, changing the spectral accelerations compared with those provided by seismic codes in case of static analyses. In this work, a parametric study has been performed in order to evaluate the elastic fundamental period of vibration of buildings as a function of structural morphology (height, plan area, ratio between plan dimensions), infills presence and distribution and soil characteristics. Acknowledgements This study was partially funded by the Italian Department of Civil Protection within the project DPC-RELUIS 2016 - RS4 ''Seismic observatory of structures and health monitoring'' and by the "Centre of Integrated Geomorphology for the Mediterranean Area - CGIAM" within the Framework Agreement with the University of Basilicata "Study, Research and Experimentation in the Field of Analysis and Monitoring of Seismic Vulnerability of Strategic and Relevant Buildings for the purposes of Civil Protection and Development of Innovative Strategies of Seismic Reinforcement".

  20. Analysis of crack propagation in concrete structures with structural information entropy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The propagation of cracks in concrete structures causes energy dissipation and release, and also causes energy redistribution in the structures. Entropy can characterize the energy redistribution. To investigate the relation between the propagation of cracks and the entropy in concrete structures, cracked concrete structures are treated as dissipative structures. Structural information entropy is defined for concrete structures. A compact tension test is conducted. Meanwhile, numerical simulations are also carried out. Both the test and numerical simulation results show that the structural information entropy in the structures can characterize the propagation of cracks in concrete structures.

  1. ENEA`s mobile treatment units for specific waters; Impianti mobili ENEA di trattamento / smaltimento rifiuti

    Energy Technology Data Exchange (ETDEWEB)

    Beone, G.; Barni, E.; Coronidi, M. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente; Bortone, G.; Gambaro, L.; Zanetti, P. [ENEA, Centro Ricerche `Ezio Clementel, Bologna (Italy). Dipt. Ambiente; Liccione, G. [ENEA, Centro Ricerche Trisaia, Matera (Italy). Dipt. Ambiente; Zanin, E.

    1997-11-01

    Solid waste production in turistic places is characterized by a large increase, up to 80 % for few months during the year. Generally a waste treatment plant is designed for a mean production and can support increases that non exceed 10 %. Treatment plants with higher capacity are not economically convenient and the excedent production is landfilled. An answer to this problem are mobile treatment units that could be used to support resident plants when higher treatment capacity is requested. Mobile units are very useful for other uses like as treatment of specific wastes (agricultural plastic bags and sheets contaminated by antiparasitics and herbicides) infective wastes from hospital and laboratories and leaches from landfills. Mobile units flexibility is also important for environmental protection actions, either scheduled on in an emergency, like as reclamation of contaminated soils, asbestos contaminated site and every time when waste transport is characterized by high cost or safety and sanitary problems.

  2. Spatial-structural interaction and strain energy structural optimisation

    NARCIS (Netherlands)

    Hofmeyer, H.; Davila Delgado, J.M.; Borrmann, A.; Geyer, P.; Rafiq, Y.; Wilde, de P.

    2012-01-01

    A research engine iteratively transforms spatial designs into structural designs and vice versa. Furthermore, spatial and structural designs are optimised. It is suggested to optimise a structural design by evaluating the strain energy of its elements and by then removing, adding, or changing the

  3. Structural cladding /clad structures:

    DEFF Research Database (Denmark)

    Beim, Anne

    2013-01-01

    tendencies, which can be traced in the use of materials, the structural features and the construction details of building systems in selected architectural works. With a particular focus at heavy constructions made of solid wood and masonry, and light weight constructions made of wooden frame structures...... and steel profiles, it is the intention to analyze, compare, and discuss how these various construction solutions point out strategies for development based on fundamentally different mindsets. The research questions address the following issues: How to learn from traditional construction principles: When...

  4. INTERFON

    CERN Multimedia

    Interfon

    2010-01-01

    Les bureaux Interfon de St Genis (Mutuelle et Coopérative) seront fermés du 9 au 20 août). Au Cern, pas de permanence « mutuelle » durant le mois d’août. Les demandes de remboursement peuvent être envoyées par courrier interne et seront transmises chaque soir au Technoparc. Le bureau de la Coopérative au Cern reste ouvert jusqu’au 22 août.   POUR VOS PROJET DE CONSTRUCTION... Vous cherchez un architecte d’intérieur ? Nous vous proposons Jean-Marc Pradéra, architecte d’intérieur qui peut vous aider et vous conseiller utilement pour améliorer votre cadre de vie, dans une maison ou dans un appartement. Concepteur de mobilier, cheminées, livings, cuisine hors standard, il coordonne les artisans choisis au meilleur prix et à la meilleure qualité (artisans jurassiens ou savoyar...

  5. High-resolution metagenomics targets major functional types in complex microbial communities

    Energy Technology Data Exchange (ETDEWEB)

    Kalyuzhnaya, Marina G.; Lapidus, Alla; Ivanova, Natalia; Copeland, Alex C.; McHardy, Alice C.; Szeto, Ernest; Salamov, Asaf; Grigoriev, Igor V.; Suciu, Dominic; Levine, Samuel R.; Markowitz, Victor M.; Rigoutsos, Isidore; Tringe, Susannah G.; Bruce, David C.; Richardson, Paul M.; Lidstrom, Mary E.; Chistoserdova, Ludmila

    2009-08-01

    Most microbes in the biosphere remain uncultured and unknown. Whole genome shotgun (WGS) sequencing of environmental DNA (metagenomics) allows glimpses into genetic and metabolic potentials of natural microbial communities. However, in communities of high complexity metagenomics fail to link specific microbes to specific ecological functions. To overcome this limitation, we selectively targeted populations involved in oxidizing single-carbon (C{sub 1}) compounds in Lake Washington (Seattle, USA) by labeling their DNA via stable isotope probing (SIP), followed by WGS sequencing. Metagenome analysis demonstrated specific sequence enrichments in response to different C{sub 1} substrates, highlighting ecological roles of individual phylotypes. We further demonstrated the utility of our approach by extracting a nearly complete genome of a novel methylotroph Methylotenera mobilis, reconstructing its metabolism and conducting genome-wide analyses. This approach allowing high-resolution genomic analysis of ecologically relevant species has the potential to be applied to a wide variety of ecosystems.

  6. O PAPEL DA CVM E DA B3 NA IMPLEMENTAÇÃO E DELIMITAÇÃO DO PROGRAMA DE INTEGRIDADE (COMPLIANCE NO BRASIL

    Directory of Open Access Journals (Sweden)

    CAROLINE DA ROSA PINHEIRO

    2017-06-01

    Full Text Available O trabalho apresenta o conceito de programa de integridade ou “compliance” como é conhecido internacionalmente, refletindo sobre o papel da Comissão de Valores Mobiliários (CVM e da B3 (Brasil, Bolsa e Balcão na implementação e delimitação do instituto no Brasil. Desse modo, também serão analisadas as competências desses órgãos, bem como sua atuação e poderes, com lastro nos diplomas legais e atos administrativos regulatórios. O método científico utilizado é o indutivo, partindo da análise de textos legais, infralegais, julgados administrativos e doutrina. A pesquisa é do tipo bibliográfica e a conclusão alcançada é pessoal, com lastro no material investigatório coligido.

  7. Structural system identification: Structural dynamics model validation

    Energy Technology Data Exchange (ETDEWEB)

    Red-Horse, J.R.

    1997-04-01

    Structural system identification is concerned with the development of systematic procedures and tools for developing predictive analytical models based on a physical structure`s dynamic response characteristics. It is a multidisciplinary process that involves the ability (1) to define high fidelity physics-based analysis models, (2) to acquire accurate test-derived information for physical specimens using diagnostic experiments, (3) to validate the numerical simulation model by reconciling differences that inevitably exist between the analysis model and the experimental data, and (4) to quantify uncertainties in the final system models and subsequent numerical simulations. The goal of this project was to develop structural system identification techniques and software suitable for both research and production applications in code and model validation.

  8. Effects of Board of Directors' Characteristics on the Quality of Accounting Information in Brazil

    Directory of Open Access Journals (Sweden)

    Luciana Holtz

    2014-12-01

    Full Text Available One of the board of directors' responsibilities is to monitor the quality of information disclosed in financial reports. The board's structural and compositional characteristics can affect the quality of reported accounting information. The aim of this study was to investigate the effects of the board's structural and compositional characteristics on the quality of accounting information of companies listed on the Brazilian Securities, Commodities, and Futures Exchange (Bolsa de Mercadorias e Futuros - BM&FBovespa. Specifically, the characteristics studied were the size and independence of the board of directors and separation of the roles of chairman and executive director. Accounting information relevance and earnings informativeness were used as proxies for the quality of accounting information. The sample included non-financial companies listed on the BM&FBovespa with annual stock market liquidity higher than 0.001, covering the period from 2008–2011. Data were collected from the Economática® database and directly from companies' annual reports and reference forms available on the Securities Commission (Comissão de Valores Mobiliários - CVM or BM&FBovespawebsites. Data analysis was undertaken using the multiple regression technique for calculating the models of accounting information relevance and earnings informativeness. The results reveal that, for companies that trade stocks on the BM&FBovespa in the Brazilian market, the characteristics of board independence and separation of the roles of chairman and executive director positively influence the quality of reported accounting information, specifically regarding the relevance of equity. Earnings informativeness is positively affected by board independence and negatively affected by larger board size (more than nine members. Overall, the results corroborate international studies such as those of Vafeas (2000, Firth, Fung, and Rui (2007, Ahmed, Hossain, and Adams (2006 and

  9. A Review of Structure Construction of Silk Fibroin Biomaterials from Single Structures to Multi-Level Structures

    Directory of Open Access Journals (Sweden)

    Yu Qi

    2017-03-01

    Full Text Available The biological performance of artificial biomaterials is closely related to their structure characteristics. Cell adhesion, migration, proliferation, and differentiation are all strongly affected by the different scale structures of biomaterials. Silk fibroin (SF, extracted mainly from silkworms, has become a popular biomaterial due to its excellent biocompatibility, exceptional mechanical properties, tunable degradation, ease of processing, and sufficient supply. As a material with excellent processability, SF can be processed into various forms with different structures, including particulate, fiber, film, and three-dimensional (3D porous scaffolds. This review discusses and summarizes the various constructions of SF-based materials, from single structures to multi-level structures, and their applications. In combination with single structures, new techniques for creating special multi-level structures of SF-based materials, such as micropatterning and 3D-printing, are also briefly addressed.

  10. Medial structure generation for registration of anatomical structures

    DEFF Research Database (Denmark)

    Vera, Sergio; Gil, Debora; Kjer, Hans Martin

    2017-01-01

    structures. Methods for generation of medial structures, however, are prone to the generation of medial artifacts (spurious branches) that traditionally need to be pruned before the medial structure can be used for further computations. The act of pruning can affect main sections of the medial surface......Medial structures (skeletons and medial manifolds) have shown capacity to describe shape in a compact way. In the field of medical imaging, they have been employed to enrich the description of organ anatomy, to improve segmentation, or to describe the organ position in relation to surrounding...

  11. Magnetic multilayer structure

    Science.gov (United States)

    Herget, Philipp; O'Sullivan, Eugene J.; Romankiw, Lubomyr T.; Wang, Naigang; Webb, Bucknell C.

    2016-07-05

    A mechanism is provided for an integrated laminated magnetic device. A substrate and a multilayer stack structure form the device. The multilayer stack structure includes alternating magnetic layers and diode structures formed on the substrate. Each magnetic layer in the multilayer stack structure is separated from another magnetic layer in the multilayer stack structure by a diode structure.

  12. Scintillator structures

    International Nuclear Information System (INIS)

    Cusano, D.A.; Prener, J.S.

    1978-01-01

    Distributed phosphor scintillator structures providing superior optical coupling to photoelectrically responsive devices together with methods for fabricating said scintillator structures are disclosed. In accordance with one embodiment of the invention relating to scintillator structures, the phosphor is distributed in a 'layered' fashion with certain layers being optically transparent so that the visible wavelength output of the scintillator is better directed to detecting devices. In accordance with another embodiment of the invention relating to scintillator structures, the phosphor is distributed throughout a transparent matrix in a continuous fashion whereby emitted light is more readily transmitted to a photodetector. Methods for fabricating said distributed phosphor scintillator structures are also disclosed. (Auth.)

  13. Seismic characteristics and identification of negative flower structures, positive flower structures, and positive structural inversion

    Energy Technology Data Exchange (ETDEWEB)

    Harding, T.P.

    1985-04-01

    Negative and positive flower structures and positive inverted structures imply specific modes of formation, and their distinctive characteristics make them important criteria for the identification of certain structural styles. A negative flower structure from the Andaman Sea consists of a shallow synform bounded by upward-spreading strands of a wrench fault that have mostly normal separations. Paralleling monoclines and oblique, en echelon normal faults flank the divergent wrench fault. A positive flower structure from the Ardmore basin, Oklahoma, consists of a shallow antiform displaced by the upward diverging strands of a wrench fault that have mostly reverse separations. En echelon folds are present on either side of this convergent wrench fault. Positive structural inversion at the Rambutan oil field, South Sumatra basin, has formed a shallow anticlinorium and has partly uplifted the underlying graben. Deeper fault segments bounding the graben have retained their normal fault profiles, but at shallow levels some of these faults have reverse separations.

  14. Structure to self-structuring: infrastructures and processes in neurobehavioural rehabilitation.

    Science.gov (United States)

    Jackson, Howard F; Hague, Gemma; Daniels, Leanne; Aguilar, Ralph; Carr, Darren; Kenyon, William

    2014-01-01

    The importance of structure in post-acute brain injury rehabilitation is repeatedly mentioned in clinical practice. However, there has been little exploration of the key elements of structure that promote greater levels of functioning and emotional/behavioural stability and how these elements are optimally integrated within the infrastructure of a rehabilitation service. The nature of structure and why it is helpful is explored initially. Thereafter, the processes involved in transition from externally supported structure to the client 'self-structuring' are described. The infrastructure for facilitating these transitional processes are considered in terms of the design of services for systemic neurorehabilitation encompassing environmental factors (e.g. living environments, vocational and recreational options, step-up services and social milieus), therapeutic alliances (rehabilitation professionals, family, friends), organisational structures (service delivery, rehabilitation coaching, transdisciplinary teams) and rehabilitation philosophies and practice. It is concluded that the process of supporting individuals to transition from the 'structure' of the environment and other people towards self-structuring skills is a critical process in rehabilitation. This is reliant upon a comprehensive and robust organisational infrastructure that can successfully and flexibly integrate the core elements of structure across a transitional pathway towards increased independence and self-structuring.

  15. Lightweight Materials and Structures (LMS): Inflatable Structures

    Data.gov (United States)

    National Aeronautics and Space Administration —  Current inflatable structures are designed on the restraint layer’s short term properties with a Factor of Safety of 4 due to lack of long-term data on structural...

  16. Structural deformation upon protein-protein interaction: a structural alphabet approach.

    Science.gov (United States)

    Martin, Juliette; Regad, Leslie; Lecornet, Hélène; Camproux, Anne-Claude

    2008-02-28

    In a number of protein-protein complexes, the 3D structures of bound and unbound partners significantly differ, supporting the induced fit hypothesis for protein-protein binding. In this study, we explore the induced fit modifications on a set of 124 proteins available in both bound and unbound forms, in terms of local structure. The local structure is described thanks to a structural alphabet of 27 structural letters that allows a detailed description of the backbone. Using a control set to distinguish induced fit from experimental error and natural protein flexibility, we show that the fraction of structural letters modified upon binding is significantly greater than in the control set (36% versus 28%). This proportion is even greater in the interface regions (41%). Interface regions preferentially involve coils. Our analysis further reveals that some structural letters in coil are not favored in the interface. We show that certain structural letters in coil are particularly subject to modifications at the interface, and that the severity of structural change also varies. These information are used to derive a structural letter substitution matrix that summarizes the local structural changes observed in our data set. We also illustrate the usefulness of our approach to identify common binding motifs in unrelated proteins. Our study provides qualitative information about induced fit. These results could be of help for flexible docking.

  17. Structural deformation upon protein-protein interaction: A structural alphabet approach

    Directory of Open Access Journals (Sweden)

    Lecornet Hélène

    2008-02-01

    Full Text Available Abstract Background In a number of protein-protein complexes, the 3D structures of bound and unbound partners significantly differ, supporting the induced fit hypothesis for protein-protein binding. Results In this study, we explore the induced fit modifications on a set of 124 proteins available in both bound and unbound forms, in terms of local structure. The local structure is described thanks to a structural alphabet of 27 structural letters that allows a detailed description of the backbone. Using a control set to distinguish induced fit from experimental error and natural protein flexibility, we show that the fraction of structural letters modified upon binding is significantly greater than in the control set (36% versus 28%. This proportion is even greater in the interface regions (41%. Interface regions preferentially involve coils. Our analysis further reveals that some structural letters in coil are not favored in the interface. We show that certain structural letters in coil are particularly subject to modifications at the interface, and that the severity of structural change also varies. These information are used to derive a structural letter substitution matrix that summarizes the local structural changes observed in our data set. We also illustrate the usefulness of our approach to identify common binding motifs in unrelated proteins. Conclusion Our study provides qualitative information about induced fit. These results could be of help for flexible docking.

  18. DNA secondary structures: stability and function of G-quadruplex structures

    Science.gov (United States)

    Bochman, Matthew L.; Paeschke, Katrin; Zakian, Virginia A.

    2013-01-01

    In addition to the canonical double helix, DNA can fold into various other inter- and intramolecular secondary structures. Although many such structures were long thought to be in vitro artefacts, bioinformatics demonstrates that DNA sequences capable of forming these structures are conserved throughout evolution, suggesting the existence of non-B-form DNA in vivo. In addition, genes whose products promote formation or resolution of these structures are found in diverse organisms, and a growing body of work suggests that the resolution of DNA secondary structures is critical for genome integrity. This Review focuses on emerging evidence relating to the characteristics of G-quadruplex structures and the possible influence of such structures on genomic stability and cellular processes, such as transcription. PMID:23032257

  19. Hybrid modelling of soil-structure interaction for embedded structures

    International Nuclear Information System (INIS)

    Gupta, S.; Penzien, J.

    1981-01-01

    The basic methods currently being used for the analysis of soil-structure interaction fail to properly model three-dimensional embedded structures with flexible foundations. A hybrid model for the analysis of soil-structure interaction is developed in this investigation which takes advantage of the desirable features of both the finite element and substructure methods and which minimizes their undesirable features. The hybrid model is obtained by partitioning the total soil-structure system into a nearfield and a far-field with a smooth hemispherical interface. The near-field consists of the structure and a finite region of soil immediately surrounding its base. The entire near-field may be modelled in three-dimensional form using the finite element method; thus, taking advantage of its ability to model irregular geometries, and the non-linear soil behavior in the immediate vicinity of the structure. (orig./WL)

  20. SSI [soil-structure interactions] and structural benchmarks

    International Nuclear Information System (INIS)

    Philippacopoulos, A.J.; Miller, C.A.; Costantino, C.J.; Graves, H.

    1986-01-01

    This paper presents the latest results of the ongoing program entitled, ''Standard Problems for Structural Computer Codes'', currently being worked on at BNL for the USNRC, Office of Nuclear Regulatory Research. During FY 1986, efforts were focussed on three tasks, namely, (1) an investigation of ground water effects on the response of Category I structures, (2) the Soil-Structure Interaction Workshop and (3) studies on structural benchmarks associated with Category I structures. The objective of the studies on ground water effects is to verify the applicability and the limitations of the SSI methods currently used by the industry in performing seismic evaluations of nuclear plants which are located at sites with high water tables. In a previous study by BNL (NUREG/CR-4588), it has been concluded that the pore water can influence significantly the soil-structure interaction process. This result, however, is based on the assumption of fully saturated soil profiles. Consequently, the work was further extended to include cases associated with variable water table depths. In this paper, results related to ''cut-off'' depths beyond which the pore water effects can be ignored in seismic calculations, are addressed. Comprehensive numerical data are given for soil configurations typical to those encountered in nuclear plant sites. These data were generated by using a modified version of the SLAM code which is capable of handling problems related to the dynamic response of saturated soils

  1. Concrete structures. Contribution to the safety assessment of existing structures

    Directory of Open Access Journals (Sweden)

    D. COUTO

    Full Text Available The safety evaluation of an existing concrete structure differs from the design of new structures. The partial safety factors for actions and resistances adopted in the design phase consider uncertainties and inaccuracies related to the building processes of structures, variability of materials strength and numerical approximations of the calculation and design processes. However, when analyzing a finished structure, a large number of unknown factors during the design stage are already defined and can be measured, which justifies a change in the increasing factors of the actions or reduction factors of resistances. Therefore, it is understood that safety assessment in existing structures is more complex than introducing security when designing a new structure, because it requires inspection, testing, analysis and careful diagnose. Strong knowledge and security concepts in structural engineering are needed, as well as knowledge about the materials of construction employed, in order to identify, control and properly consider the variability of actions and resistances in the structure. With the intention of discussing this topic considered complex and diffuse, this paper presents an introduction to the safety of concrete structures, a synthesis of the recommended procedures by Brazilian standards and another codes, associated with the topic, as well a realistic example of the safety assessment of an existing structure.

  2. Space Structure Development

    Science.gov (United States)

    Smith, Thomas

    2015-01-01

    The duration of my Summer 2015 Internship Tour at NASA's Johnson Space Center was spent working in the Structural Engineering Division's Structures Branch. One of the two main roles of the Structures Branch, ES2, is to ensure the structural integrity of spacecraft vehicles and the structural subsystems needed to support those vehicles. The other main objective of this branch is to develop the lightweight structures that are necessary to take humans beyond Low-Earth Orbit. Within ES2, my four projects involved inflatable space structure air bladder material testing; thermal and impact material testing for spacecraft windows; structural analysis on a joint used in the Boeing CST-100 airbag system; and an additive manufacturing design project.

  3. Structural Health Monitoring Based on Combined Structural Global and Local Frequencies

    Directory of Open Access Journals (Sweden)

    Jilin Hou

    2014-01-01

    Full Text Available This paper presents a parameter estimation method for Structural Health Monitoring based on the combined measured structural global frequencies and structural local frequencies. First, the global test is experimented to obtain the low order modes which can reflect the global information of the structure. Secondly, the mass is added on the member of structure to increase the local dynamic characteristic and to make the member have local primary frequency, which belongs to structural local frequency and is sensitive to local parameters. Then the parameters of the structure can be optimized accurately using the combined structural global frequencies and structural local frequencies. The effectiveness and accuracy of the proposed method are verified by the experiment of a space truss.

  4. Nonlinear seismic soil-structure interaction analysis of nuclear power plant structures

    International Nuclear Information System (INIS)

    Khanna, J.K.; Setlur, A.V.; Pathak, D.V.

    1977-01-01

    The heterogeneous and nonlinear soil medium and the detailed three-dimensional structure are synthesized to determine the seismic response to soil-structure systems. The approach is particularly attractive in a design office environment since it: a) leads to interactive motion at the soil-structure interface; b) uses existing public domain programs such as SAPIV, LUSH and FLUSH with marginal modifications; and c) meets current regulatory requirements for soil-structure interaction analysis. Past methods differ from each other depending on the approach adopted for soil and structure representations and procedures for solving the governing differential equations. Advantages and limitations of these methods are reviewed. In the current approach, the three-dimensional structure is represented by the dynamic characteristics of its fixed base condition. This representation is ideal when structures are designed to be within elastic range. An important criterion is the design of the nuclear power plant structures. Model damping coefficients are varied to reflect the damping properties of different structural component materials. The detailed structural model is systematically reduced to reflect important dynamic behavior with simultaneous storing of intermediate information for retrieval of detailed structural response. Validity of the approach has been established with simple numerical experiments. (Auth.)

  5. Structural Evaluation Procedures for Heavy Wood Truss Structures

    National Research Council Canada - National Science Library

    Issa, Mohsen

    1998-01-01

    .... An evaluation procedure for wood structures differs from conventional methods used in steel, concrete, and masonry structures because, in wood construction, the allowable stresses used in design...

  6. Scintillator structure

    International Nuclear Information System (INIS)

    Cusano, D.A.; Prener, J.S.

    1979-01-01

    A scintillator structure comprises at least one layer of transparent fused quartz with a phosphor coating on one or both sides adjacent to at least one transparent layer of epoxy resin which directs light from the phosphor to a detector. The phosphor layer may be formed from a powder optionally with a binder, a single crystal or a melt, or by evaporation or sintering. A plurality of multiple layers may be used or the structure tilted for greater absorption. The structure may be surrounded by another such structure optionally operating in cascade with the first. Many phosphors are specified. A scintillator structure comprises phosphor particles dispersed in epoxy resin or copoly imide-silicone and cast in a multi-compartment box with long sides transparent to X-rays and dividers opaque to X-rays. (UK)

  7. Design optimisation of the ATLAS Barrel Toroid structure - the warm structure

    International Nuclear Information System (INIS)

    Daeel, A.; Desvard, J-P.; Pabot, Y.; Sun, Z.; Hille, H. van; Vedrine, P.

    2001-01-01

    The magnetic bending of muon tracks for the ATLAS Muon Spectrometer is provided by the large air-core toroid magnets. The Barrel Toroid structure, named the warm structure, is an open structure inside which the muon chambers are installed. The physics performance of the muon spectrometer imposes stringent requirements on the design of the warm structure. It should support the muon chambers with required precision and stability, the deformation of the structure must be minimised. At the same time, the quantities of the materials used in the structure must also be minimised. Through extensive structural analyses, the design optimisation has been achieved to fit with the physics requirements. This paper gives an overview on the design considerations of the warm structure

  8. Aerospace structural design process improvement using systematic evolutionary structural modeling

    Science.gov (United States)

    Taylor, Robert Michael

    2000-10-01

    A multidisciplinary team tasked with an aircraft design problem must understand the problem requirements and metrics to produce a successful design. This understanding entails not only knowledge of what these requirements and metrics are, but also how they interact, which are most important (to the customer as well as to aircraft performance), and who in the organization can provide pertinent knowledge for each. In recent years, product development researchers and organizations have developed and successfully applied a variety of tools such as Quality Function Deployment (QFD) to coordinate multidisciplinary team members. The effectiveness of these methods, however, depends on the quality and fidelity of the information that team members can input. In conceptual aircraft design, structural information is of lower quality compared to aerodynamics or performance because it is based on experience rather than theory. This dissertation shows how advanced structural design tools can be used in a multidisciplinary team setting to improve structural information generation and communication through a systematic evolution of structural detail. When applied to conceptual design, finite element-based structural design tools elevate structural information to the same level as other computationally supported disciplines. This improved ability to generate and communicate structural information enables a design team to better identify and meet structural design requirements, consider producibility issues earlier, and evaluate structural concepts. A design process experiment of a wing structural layout in collaboration with an industrial partner illustrates and validates the approach.

  9. Discrete Optimization of Internal Part Structure via SLM Unit Structure-Performance Database

    Directory of Open Access Journals (Sweden)

    Li Tang

    2018-01-01

    Full Text Available The structural optimization of the internal structure of parts based on three-dimensional (3D printing has been recognized as being important in the field of mechanical design. The purpose of this paper is to present a creation of a unit structure-performance database based on the selective laser melting (SLM, which contains various structural units with different functions and records their structure and performance characteristics so that we can optimize the internal structure of parts directly, according to the database. The method of creating the unit structure-performance database was introduced in this paper and several structural units of the unit structure-performance database were introduced. The bow structure unit was used to show how to create the structure-performance database of the unit as an example. Some samples of the bow structure unit were designed and manufactured by SLM. These samples were tested in the WDW-100 compression testing machine to obtain their performance characteristics. After this, the paper collected all data regarding unit structure parameters, weight, performance characteristics, and other data; and, established a complete set of data from the bow structure unit for the unit structure-performance database. Furthermore, an aircraft part was reconstructed conveniently to be more lightweight according to the unit structure-performance database. Its weight was reduced by 36.8% when compared with the original structure, while the strength far exceeded the requirements.

  10. Structure of simple liquids; Structure des liquides simples

    Energy Technology Data Exchange (ETDEWEB)

    Blain, J F [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1969-07-01

    The results obtained by application to argon and sodium of the two important methods of studying the structure of liquids: scattering of X-rays and neutrons, are presented on one hand. On the other hand the principal models employed for reconstituting the structure of simple liquids are exposed: mathematical models, lattice models and their derived models, experimental models. (author) [French] On presente d'une part les resultats obtenus par application a l'argon et au sodium des deux principales methodes d'etude de la structure des liquides: la diffusion des rayons X et la diffusion des neutrons; d'autre part, les principaux modeles employes pour reconstituer la structure des liquides simples sont exposes: modeles mathematiques, modeles des reseaux et modeles derives, modeles experimentaux. (auteur)

  11. Structural biology by NMR: structure, dynamics, and interactions.

    Directory of Open Access Journals (Sweden)

    Phineus R L Markwick

    2008-09-01

    Full Text Available The function of bio-macromolecules is determined by both their 3D structure and conformational dynamics. These molecules are inherently flexible systems displaying a broad range of dynamics on time-scales from picoseconds to seconds. Nuclear Magnetic Resonance (NMR spectroscopy has emerged as the method of choice for studying both protein structure and dynamics in solution. Typically, NMR experiments are sensitive both to structural features and to dynamics, and hence the measured data contain information on both. Despite major progress in both experimental approaches and computational methods, obtaining a consistent view of structure and dynamics from experimental NMR data remains a challenge. Molecular dynamics simulations have emerged as an indispensable tool in the analysis of NMR data.

  12. Task structure, need for structure, and creativity

    NARCIS (Netherlands)

    Rietzschel, Eric; Slijkhuis, Marjette; Van Yperen, Nico W.

    2014-01-01

    Although creativity is often seen as requiring spontaneity and flexibility, recent work suggests that there is creative potential in a structured and systematic approach as well. In a series of four experiments, we show that when Personal Need for Structure (PNS) is high, either chronic (Study 1) or

  13. Structural design of nuclear power plant using stiffened steel plate concrete structure

    International Nuclear Information System (INIS)

    Moon, Ilhwan; Kim, Sungmin; Mun, Taeyoup; Kim, Keunkyeong; Sun, Wonsang

    2009-01-01

    Nuclear power is an alternative energy source that is conducive to mitigate the environmental strains. The countries having nuclear power plants are encouraging research and development sector to find ways to construct safer and more economically feasible nuclear power plants. Modularization using Steel Plate Concrete(SC) structure has been proposed as a solution to these efforts. A study of structural modules using SC structure has been performed for shortening of construction period and enhancement of structural safety of NPP structures in Korea. As a result of the research, the design code and design techniques based on limit state design method has been developed. The design code has been developed through various structural tests and theoretical studies, and it has been modified by application design of SC structure for NPP buildings. The code consists of unstiffened SC wall design, stiffened SC wall design, Half-SC slab design, stud design, connection design and so on. The stiffened steel plate concrete(SSC) wall is SC structure whose steel plates with ribs are composed on both sides of the concrete wall, and this structure was developed for improved constructability and safety of SC structure. This paper explains a design application of SC structure for a sample building specially devised to reflect all of major structural properties of main buildings of APR1400. In addition, Stiffening effect of SSC structure is evaluated and structural efficiency of SSC structure is verified in comparison with that of unstiffened SC structure. (author)

  14. Strategy implemented through structuring and new structures

    DEFF Research Database (Denmark)

    Nielsen, Renate

    Research objective: With the purpose of generating a new understanding of how development in organisations take place, an interpretive perspective at continuous processes in organisations will be applied: more specifically at how organisational interpretation forms an organisation's strategy...... and how the strategy is implemented through structuring, new structures and routines....

  15. Atomic-level structure and structure-property relationship in metallic glass

    Science.gov (United States)

    Cheng, Yongqiang

    One of the key tasks in material science is to understand the structure and structure-property relationship. The recently emerging bulk metallic glasses (BMGs) have demonstrated unique properties, especially intriguing mechanical properties such as their high strength and high propensity to localize deformation in shear bands. However, a comprehensive understanding of the structure of BMGs has been hindered by the complexity of these amorphous materials. Even more challenging is the structure-property correlation, which has been well established in crystals but has been seriously lacking for BMGs. This thesis presents a systematic study of the atomic-level structures of two representative BMGs, Cu-Zr and Cu-Zr-Al. The interpenetrating Cu-centered icosahedral clusters have been identified to be the primary structural feature. The fraction of icosahedra increases with increasing Cu or Al contents, and with decreasing cooling rate. The effect of Al in improving the icosahedral order is two-fold: the geometric effect due to the atomic-size mismatch and the chemical effect originated from the Cu-Al bond shortening. The resolved structure is used to study the structure-property relationship. The full icosahedra are found to be responsible for the dynamical slowdown of the supercooled liquid, which underlies the non-Arrhenius behavior, and explains the composition dependence of glass transition temperature, glass forming ability, and the room temperature strength. By simulated deformation, the initiation of plasticity and tendency for strain localization are also investigated. The full icosahedra are found to be the most rigid and resistant cluster with solid-like character, while the unstable clusters with liquid-like character serve as the fertile sites for initiating shear transformations. In addition, the elastic moduli are calculated and analyzed, and the origins of the different configurational dependence of shear modulus (G) and bulk modulus ( B) are explained. The

  16. Structuralism.

    Science.gov (United States)

    Piaget, Jean

    Provided is an overview of the analytical method known as structuralism. The first chapter discusses the three key components of the concept of a structure: the view of a system as a whole instead of so many parts; the study of the transformations in the system; and the fact that these transformations never lead beyond the system but always…

  17. Enzymatic hydrolysis of various pretreated lignocellulosic substrates and the fermentation of the liberated sugars to ethanol and butanediol

    Energy Technology Data Exchange (ETDEWEB)

    Saddler, J.N.; Mes-Hartree, M.; Yu, E.K.C.; Brownell, H.H.

    1983-01-01

    Aspen wood and wheat straw were pretreated by exposure to steam at elevated temperatures. Chemical analysis of the substrates revealed that steam explosion differentially decomposed the pentosan component while leaving the glucan portion relatively unchanged. The pretreated residues could be used as substrates for growth of Trichoderma reesei C30 and T. harzianum E58. The cellulase activities detected were in some cases three times as high as those found when Solka Floc was used as the substrate. Culture filtrates of T. harzianum E58 could efficiently hydrolyze the hemicellulose-rich water-soluble fractions. This material was fermented by Klebsiella pneumoniae with 0.4-0.5 g of 2,3-butanediol produced per gram of sugar utilized. Once the steam-exploded residues had been water and alkali extracted, the enzymatically hydrolyzed substrates were readily fermented by Saccharomyces cerevisiae or Zymononas mobilis with values as high as 2% (w/v) ethanol obtained from 5% steam-exploded wood fractions. 30 references, 2 figures, 8 tables.

  18. Canoë-Kayak Club

    CERN Multimedia

    Canoë-Kayak Club

    2012-01-01

    Mobilisation Initiatives Océanes.   Pour la deuxième année consécutive, le Canoë Kayak CERN s’est mobilisé pour soutenir l’action de la fondation Surfrider en participant aux Initiatives Océanes qui se déroulent chaque année au début du printemps pour lutter contre les déchets qui polluent nos océans, plages, lacs et rivières. En 2011, cela représentait dans le monde 40’000 participants, 7’500 scolaires, 34 pays et plus de 950 nettoyages. Le Canoë kayak CERN a souhaité poursuivre l’action mené en 2011, de la Jonction (à Genève) jusqu’au Lignon, en continuant de nettoyer les berges du Rhône du Lignon jusqu’au port d’Aire-la-Ville et la plage de Peney, avec une équipe sur l'eau, en cano...

  19. Les territorialités émergentes des migrants marocains

    Directory of Open Access Journals (Sweden)

    Sabrina Marchandise

    2013-05-01

    Full Text Available Par l’usage et les pratiques liées aux TIC, l’espace virtuel devient un support des relations sociales mobilisées dans la migration, espace de socialisation (par la communication, la communauté et espace de ressources (culturelle, économique et sociale, ayant des traductions concrètes dans l’espace physique. Nous nous interrogeons alors sur l’articulation des territoires physiques et non physiques des migrants marocains. Cet article se fonde sur une expérimentation en cours d’exploration et de visualisation du web diasporique. Nous en livrons ici les premiers éléments de résultats, à la fois à partir de la représentation d’un corpus de sites web, de la localisation des sites et destinataires et également par une réflexion sur l’apport des représentations des réseaux sociaux sur le web.

  20. Globalização e poder de estado: circulação internacional de elites e hierarquias do campo jurídico brasileiro

    Directory of Open Access Journals (Sweden)

    Fabiano Engelmann

    2012-01-01

    Full Text Available Prenant comme point de départ la problématique de la mondialisation des travaux d'experts concernant l'État, on examine les conditions d'internationalisation du champ juridique brésilien visant surtout le rapport entre le capital international mobilisé par les juristes et la hiérarchisation dans ce champ. Cette analyse part surtout de la comparaison des trajectoires universitaires, professionnelles et politiques de trois segments représentatifs de l'élite juridique: enseignants dans les cours de doctorat en droit, avocats associés aux plus importants cabinets juridiques et ministres du Supérieur Tribunal de Justice et du Supérieur Tribunal Fédéral. Les divers liens avec l'espace international peuvent être rapportés aux différentes positions dans le champ juridique brésilien et à leur relation avec l'espace politique et économique.

  1. Audiovisivi per línsegnamento e nuove tecnologie nelle classi 2.0 della regione Emilia-Romagna

    Directory of Open Access Journals (Sweden)

    Laura Corazza

    2015-01-01

    Full Text Available I bambini e i ragazzi nel nuovo millennio sono forse più avvezzi alla visione di un film o di una trasmissione televisiva che non alla lettura di un libro. Quello che è certo, è che sono sottoposti a un bombardamento mediatico senza precedenti grazie a canali televisivi specializzati nella produzione di programmi per l’infanzia e l’adolescenza, alla Rete Internet e ai dispositivi mobili di ultima generazione. E a scuola? Come cambia la didattica? Al laboratorio Mela abbiamo documentato con un video l’avvio della prima esperienza delle Cl@ssi 2.0 in Emilia-Romagna nelle scuole secondarie inferiori. Alla fine dei 3 anni di sperimentazione, durante i quali gli insegnanti hanno utilizzato LIM, computer in classe e Moodle per l’insegnamento a distanza, abbiamo invece cercato di capire, con un questionario, come e quanto vengano utilizzati i video per la didattica. Ne sono seguite alcune riflessioni.

  2. Building structures

    CERN Document Server

    Ambrose, James

    2011-01-01

    James Ambrose is Editor of the Parker/Ambrose Series of Simplified Design Guides. He practiced as an architect in California and Illinois and as a structural engineer in Illinois. He was a professor of architecture at the University of Southern California. Patrick Tripeny is an Associate Professor, former director of the School of Architecture, and the current Director of the Center for Teaching and Learning Excellence at the University of Utah. He is a licensed architect in California. He has been the recipient of a number of teaching awards at the local and national level for his work in teaching structures and design. With James Ambrose, he is the coauthor of Simplified Engineering for Architects and Builders, Eleventh Edition; Simplified Design of Steel Structures, Eighth Edition; Simplified Design of Concrete Structures, Eighth Edition; and Simplified Design of Wood Structures, Sixth Edition, all published by Wiley.

  3. Robustness of Structures

    DEFF Research Database (Denmark)

    Faber, Michael Havbro; Vrouwenvelder, A.C.W.M.; Sørensen, John Dalsgaard

    2011-01-01

    In 2005, the Joint Committee on Structural Safety (JCSS) together with Working Commission (WC) 1 of the International Association of Bridge and Structural Engineering (IABSE) organized a workshop on robustness of structures. Two important decisions resulted from this workshop, namely...... ‘COST TU0601: Robustness of Structures’ was initiated in February 2007, aiming to provide a platform for exchanging and promoting research in the area of structural robustness and to provide a basic framework, together with methods, strategies and guidelines enhancing robustness of structures...... the development of a joint European project on structural robustness under the COST (European Cooperation in Science and Technology) programme and the decision to develop a more elaborate document on structural robustness in collaboration between experts from the JCSS and the IABSE. Accordingly, a project titled...

  4. Improving the accuracy of protein secondary structure prediction using structural alignment

    Directory of Open Access Journals (Sweden)

    Gallin Warren J

    2006-06-01

    Full Text Available Abstract Background The accuracy of protein secondary structure prediction has steadily improved over the past 30 years. Now many secondary structure prediction methods routinely achieve an accuracy (Q3 of about 75%. We believe this accuracy could be further improved by including structure (as opposed to sequence database comparisons as part of the prediction process. Indeed, given the large size of the Protein Data Bank (>35,000 sequences, the probability of a newly identified sequence having a structural homologue is actually quite high. Results We have developed a method that performs structure-based sequence alignments as part of the secondary structure prediction process. By mapping the structure of a known homologue (sequence ID >25% onto the query protein's sequence, it is possible to predict at least a portion of that query protein's secondary structure. By integrating this structural alignment approach with conventional (sequence-based secondary structure methods and then combining it with a "jury-of-experts" system to generate a consensus result, it is possible to attain very high prediction accuracy. Using a sequence-unique test set of 1644 proteins from EVA, this new method achieves an average Q3 score of 81.3%. Extensive testing indicates this is approximately 4–5% better than any other method currently available. Assessments using non sequence-unique test sets (typical of those used in proteome annotation or structural genomics indicate that this new method can achieve a Q3 score approaching 88%. Conclusion By using both sequence and structure databases and by exploiting the latest techniques in machine learning it is possible to routinely predict protein secondary structure with an accuracy well above 80%. A program and web server, called PROTEUS, that performs these secondary structure predictions is accessible at http://wishart.biology.ualberta.ca/proteus. For high throughput or batch sequence analyses, the PROTEUS programs

  5. Shell-like structures

    CERN Document Server

    Altenbach, Holm

    2011-01-01

    In this volume, scientists and researchers from industry discuss the new trends in simulation and computing shell-like structures. The focus is put on the following problems: new theories (based on two-dimensional field equations but describing non-classical effects), new constitutive equations (for materials like sandwiches, foams, etc. and which can be combined with the two-dimensional shell equations), complex structures (folded, branching and/or self intersecting shell structures, etc.) and shell-like structures on different scales (for example: nano-tubes) or very thin structures (similar

  6. Basic structural dynamics

    CERN Document Server

    Anderson, James C

    2012-01-01

    A concise introduction to structural dynamics and earthquake engineering Basic Structural Dynamics serves as a fundamental introduction to the topic of structural dynamics. Covering single and multiple-degree-of-freedom systems while providing an introduction to earthquake engineering, the book keeps the coverage succinct and on topic at a level that is appropriate for undergraduate and graduate students. Through dozens of worked examples based on actual structures, it also introduces readers to MATLAB, a powerful software for solving both simple and complex structural d

  7. Some considerations on the dynamic structure-soil-structure interactions analysis

    International Nuclear Information System (INIS)

    Matthees, W.

    1979-01-01

    A mixed method has been developed for the approximate analysis of soil-structure or structure-soil-structure interaction problems due to earthquakes. In order to produce comparable results of interaction problems as well as for shallow and for deep soils due to the same earthquake excitation (accelerogram) situated always at the lower bedrock boundary, the analysis is performed in two steps: 1) Calculation of the complex transfer function and the response of the upper interior boundary of a layered soil-system which is connected at its top to a soil-structure-system, using the one-dimensional deconvolution. 2) By making a complete interaction analysis of the surface soil-structure-system using the interior boundary excitation of the calculated response from step 1. The depth of the soil-structure-system must be chosen large enough to exclude interaction effects down to the layered soil-system's interior boundary. (orig.)

  8. Structures in sculptures

    DEFF Research Database (Denmark)

    Vanggaard, Ole

    Conceptual design of structures in architecture involves a dialog between a structural and an architectural concept. The architecture is very often changed in this process. The dialog between the parties are described and well known. It is often very difficult to bridge the gab between...... the different concepts and find a final synthesis, but the problem is known. Large sculptures represent structural challenges. The design of the supports inside the structures reveals often a very different world from the outside view of the sculpture. The piece of art and its structure may have two very...... different lives. A sculpture of today may be very dissimilar from what we have seen earlier. The structure becomes sometimes a visual part of the art. Ultimately, there may not be any distinction between structure and art. The technical demand, the durability and the safety are just as important for a large...

  9. Electromagnetic and structural interaction analysis of curved shell structures

    International Nuclear Information System (INIS)

    Horie, T.; Niho, T.

    1993-01-01

    This paper describes a finite element formulation of the eddy current and structure coupled problem for curved shell structures. Coupling terms produced by curved geometry as well as flat plate geometry were obtained. Both matrix equations for eddy current and structure were solved simultaneously using coupling sub-matrices. TEAM Workshop bench mark problem 16 was solved to verify the formulation and the computer code. Agreement with experimental results was very good for such plate problem. A coupled problem for cylindrical shell structure was also analyzed. Influence of each coupling term was examined. The next topic is the eigenvalues of the coupled equations. Although the coupled matrix equations are not symmetric, symmetry was obtained by introducing a symmetrizing variable. The eigenvalues of the coupled matrix equations are different from those obtained from the uncoupled equations because of the influence of the coupling sub-matrix components. Some parameters obtained by the eigenvalue analysis have characteristics of parameters which indicate the intensity of electromagnetic structural coupling effect. (author)

  10. Structure of polysaccharide and structural analysis by x-ray

    International Nuclear Information System (INIS)

    Yuguchi, Yoshiaki

    2010-01-01

    Polysaccharides occur in plants and the living body in the solid, gel, or liquid. They have a highly structural diversity and possess the potential to be used for development of new materials and energy sources. So it is very important to understand their molecular structure under various conditions. This review introduces the structural characteristics of polysaccharides and the examples of their analysis by the X-ray scattering method. (author)

  11. Combustible structural composites and methods of forming combustible structural composites

    Science.gov (United States)

    Daniels, Michael A.; Heaps, Ronald J.; Steffler, Eric D.; Swank, W. David

    2013-04-02

    Combustible structural composites and methods of forming same are disclosed. In an embodiment, a combustible structural composite includes combustible material comprising a fuel metal and a metal oxide. The fuel metal is present in the combustible material at a weight ratio from 1:9 to 1:1 of the fuel metal to the metal oxide. The fuel metal and the metal oxide are capable of exothermically reacting upon application of energy at or above a threshold value to support self-sustaining combustion of the combustible material within the combustible structural composite. Structural-reinforcing fibers are present in the composite at a weight ratio from 1:20 to 10:1 of the structural-reinforcing fibers to the combustible material. Other embodiments and aspects are disclosed.

  12. Study of structural reliability of existing concrete structures

    Science.gov (United States)

    Druķis, P.; Gaile, L.; Valtere, K.; Pakrastiņš, L.; Goremikins, V.

    2017-10-01

    Structural reliability of buildings has become an important issue after the collapse of a shopping center in Riga 21.11.2013, caused the death of 54 people. The reliability of a building is the practice of designing, constructing, operating, maintaining and removing buildings in ways that ensure maintained health, ward suffered injuries or death due to use of the building. Evaluation and improvement of existing buildings is becoming more and more important. For a large part of existing buildings, the design life has been reached or will be reached in the near future. The structures of these buildings need to be reassessed in order to find out whether the safety requirements are met. The safety requirements provided by the Eurocodes are a starting point for the assessment of safety. However, it would be uneconomical to require all existing buildings and structures to comply fully with these new codes and corresponding safety levels, therefore the assessment of existing buildings differs with each design situation. This case study describes the simple and practical procedure of determination of minimal reliability index β of existing concrete structures designed by different codes than Eurocodes and allows to reassess the actual reliability level of different structural elements of existing buildings under design load.

  13. Structure-borne sound structural vibrations and sound radiation at audio frequencies

    CERN Document Server

    Cremer, L; Petersson, Björn AT

    2005-01-01

    Structure-Borne Sound"" is a thorough introduction to structural vibrations with emphasis on audio frequencies and the associated radiation of sound. The book presents in-depth discussions of fundamental principles and basic problems, in order to enable the reader to understand and solve his own problems. It includes chapters dealing with measurement and generation of vibrations and sound, various types of structural wave motion, structural damping and its effects, impedances and vibration responses of the important types of structures, as well as with attenuation of vibrations, and sound radi

  14. Structural Health Monitoring: Numerical Damage Predictor for Composite Structures

    National Research Council Canada - National Science Library

    Lannamann, Daniel

    2001-01-01

    .... Wide use of composites is found in aircraft, armored vehicles, ships and civil structures This present research demonstrates the ability to numerically detect damage in a composite sandwich structure...

  15. Structural stability and electronic structure of YCu ductile ...

    African Journals Online (AJOL)

    We investigate the structural, elastic and electronic properties of cubic YCu intermetallic compound. Which crystallize in the CsCl- B2 type structure, the investigated using the first principle full potential linearized augmented plane wave method (FP-LAPW) within density functional Theory (DFT). We used generalized ...

  16. Accurate protein structure modeling using sparse NMR data and homologous structure information.

    Science.gov (United States)

    Thompson, James M; Sgourakis, Nikolaos G; Liu, Gaohua; Rossi, Paolo; Tang, Yuefeng; Mills, Jeffrey L; Szyperski, Thomas; Montelione, Gaetano T; Baker, David

    2012-06-19

    While information from homologous structures plays a central role in X-ray structure determination by molecular replacement, such information is rarely used in NMR structure determination because it can be incorrect, both locally and globally, when evolutionary relationships are inferred incorrectly or there has been considerable evolutionary structural divergence. Here we describe a method that allows robust modeling of protein structures of up to 225 residues by combining (1)H(N), (13)C, and (15)N backbone and (13)Cβ chemical shift data, distance restraints derived from homologous structures, and a physically realistic all-atom energy function. Accurate models are distinguished from inaccurate models generated using incorrect sequence alignments by requiring that (i) the all-atom energies of models generated using the restraints are lower than models generated in unrestrained calculations and (ii) the low-energy structures converge to within 2.0 Å backbone rmsd over 75% of the protein. Benchmark calculations on known structures and blind targets show that the method can accurately model protein structures, even with very remote homology information, to a backbone rmsd of 1.2-1.9 Å relative to the conventional determined NMR ensembles and of 0.9-1.6 Å relative to X-ray structures for well-defined regions of the protein structures. This approach facilitates the accurate modeling of protein structures using backbone chemical shift data without need for side-chain resonance assignments and extensive analysis of NOESY cross-peak assignments.

  17. Antibody structural modeling with prediction of immunoglobulin structure (PIGS)

    DEFF Research Database (Denmark)

    Marcatili, Paolo; Olimpieri, Pier Paolo; Chailyan, Anna

    2014-01-01

    Antibodies (or immunoglobulins) are crucial for defending organisms from pathogens, but they are also key players in many medical, diagnostic and biotechnological applications. The ability to predict their structure and the specific residues involved in antigen recognition has several useful...... applications in all of these areas. Over the years, we have developed or collaborated in developing a strategy that enables researchers to predict the 3D structure of antibodies with a very satisfactory accuracy. The strategy is completely automated and extremely fast, requiring only a few minutes (∼10 min...... on average) to build a structural model of an antibody. It is based on the concept of canonical structures of antibody loops and on our understanding of the way light and heavy chains pack together....

  18. Kinematics, structural mechanics, and design of origami structures with smooth folds

    Science.gov (United States)

    Peraza Hernandez, Edwin Alexander

    Origami provides novel approaches to the fabrication, assembly, and functionality of engineering structures in various fields such as aerospace, robotics, etc. With the increase in complexity of the geometry and materials for origami structures that provide engineering utility, computational models and design methods for such structures have become essential. Currently available models and design methods for origami structures are generally limited to the idealization of the folds as creases of zeroth-order geometric continuity. Such an idealization is not proper for origami structures having non-negligible thickness or maximum curvature at the folds restricted by material limitations. Thus, for general structures, creased folds of merely zeroth-order geometric continuity are not appropriate representations of structural response and a new approach is needed. The first contribution of this dissertation is a model for the kinematics of origami structures having realistic folds of non-zero surface area and exhibiting higher-order geometric continuity, here termed smooth folds. The geometry of the smooth folds and the constraints on their associated kinematic variables are presented. A numerical implementation of the model allowing for kinematic simulation of structures having arbitrary fold patterns is also described. Examples illustrating the capability of the model to capture realistic structural folding response are provided. Subsequently, a method for solving the origami design problem of determining the geometry of a single planar sheet and its pattern of smooth folds that morphs into a given three-dimensional goal shape, discretized as a polygonal mesh, is presented. The design parameterization of the planar sheet and the constraints that allow for a valid pattern of smooth folds and approximation of the goal shape in a known folded configuration are presented. Various testing examples considering goal shapes of diverse geometries are provided. Afterwards, a

  19. Optimal Priority Structure, Capital Structure, and Investment

    OpenAIRE

    Dirk Hackbarth; David C. Mauer

    2012-01-01

    We study the interaction between financing and investment decisions in a dynamic model, where the firm has multiple debt issues and equityholders choose the timing of investment. Jointly optimal capital and priority structures can virtually eliminate investment distortions because debt priority serves as a dynamically optimal contract. Examining the relative efficiency of priority rules observed in practice, we develop several predictions about how firms adjust their priority structure in res...

  20. Diverter structure

    Energy Technology Data Exchange (ETDEWEB)

    Nayama, Risuke; Toyota, Masahiko; Tsujimura, Seiichi

    1995-11-21

    The present invention concerns a vacuum vessel for a tokamak-type nuclear fusion plasma experimental device, and provides a divertor structure capable of reducing a distance of a plasma facing surface of a divertor structure and an inner wall of the vacuum vessel while maintaining cooling and heat removing performance. Namely, in the divertor structure of the present invention, a compulsory cooling channel on the side receiving high temperature load is made of a highly heat conductive material such as copper. The compulsory cooling channel on the side secured to a substrate is made of a material having high mechanical strength, for example, stainless steel. With such a constitution, the compulsory cooling channel on the side receiving high temperature load transfers the heat received by an armour material from plasmas efficiently to coolants. The opposite side can be secured to the inner wall of the vacuum vessel with satisfactory mechanical strength without interposing other additional materials. As a result, the structure of the present invention can reduce the distance of the plasma facing surface of the divertor structure and the inner wall of the vacuum vessel while maintaining the cooling and heat removing performance. (I.S.).

  1. Diverter structure

    International Nuclear Information System (INIS)

    Nayama, Risuke; Toyota, Masahiko; Tsujimura, Seiichi.

    1995-01-01

    The present invention concerns a vacuum vessel for a tokamak-type nuclear fusion plasma experimental device, and provides a divertor structure capable of reducing a distance of a plasma facing surface of a divertor structure and an inner wall of the vacuum vessel while maintaining cooling and heat removing performance. Namely, in the divertor structure of the present invention, a compulsory cooling channel on the side receiving high temperature load is made of a highly heat conductive material such as copper. The compulsory cooling channel on the side secured to a substrate is made of a material having high mechanical strength, for example, stainless steel. With such a constitution, the compulsory cooling channel on the side receiving high temperature load transfers the heat received by an armour material from plasmas efficiently to coolants. The opposite side can be secured to the inner wall of the vacuum vessel with satisfactory mechanical strength without interposing other additional materials. As a result, the structure of the present invention can reduce the distance of the plasma facing surface of the divertor structure and the inner wall of the vacuum vessel while maintaining the cooling and heat removing performance. (I.S.)

  2. Development of the tube bundle structure for fluid-structure interaction analysis model

    International Nuclear Information System (INIS)

    Yoon, Kyung Ho; Kim, Jae Yong

    2010-02-01

    Tube bundle structures within a Boiler or heat exchanger are laid the fluid-structure, thermal-structure and fluid-thermal-structure coupled boundary condition. In these complicated boundary conditions, Fluid-structure interaction (FSI) occurs when fluid flow causes deformation of the structure. This deformation, in turn, changes the boundary conditions for the fluid flow. The structural analysis discipline, and then independently analyzed each other. However, the fluid dynamic force effect the behavior of the structure, and the vibration amplitude of the structure to fluid. FSI analysis model was separately created fluid and structure model, and then defined the fsi boundary condition, and simultaneously analyzed in one domain. The analysis results were compared with those of the experimental method for validating the analysis model. Flow-induced vibration test was executed with single rod configuration. The vibration amplitudes of a fuel rod were measured by the laser vibro-meter system in x and y-direction. The analyses results were not closely with the test data, but the trend was very similar with the test result. In fsi coupled analysis case, the turbulent model was very important with the reliability of the accuracy of the analysis model. Therefore, the analysis model will be needed to further study

  3. Hydraulic structures

    CERN Document Server

    Chen, Sheng-Hong

    2015-01-01

    This book discusses in detail the planning, design, construction and management of hydraulic structures, covering dams, spillways, tunnels, cut slopes, sluices, water intake and measuring works, ship locks and lifts, as well as fish ways. Particular attention is paid to considerations concerning the environment, hydrology, geology and materials etc. in the planning and design of hydraulic projects. It also considers the type selection, profile configuration, stress/stability calibration and engineering countermeasures, flood releasing arrangements and scouring protection, operation and maintenance etc. for a variety of specific hydraulic structures. The book is primarily intended for engineers, undergraduate and graduate students in the field of civil and hydraulic engineering who are faced with the challenges of extending our understanding of hydraulic structures ranging from traditional to groundbreaking, as well as designing, constructing and managing safe, durable hydraulic structures that are economical ...

  4. Antibody structural modeling with prediction of immunoglobulin structure (PIGS)

    KAUST Repository

    Marcatili, Paolo

    2014-11-06

    © 2014 Nature America, Inc. All rights reserved. Antibodies (or immunoglobulins) are crucial for defending organisms from pathogens, but they are also key players in many medical, diagnostic and biotechnological applications. The ability to predict their structure and the specific residues involved in antigen recognition has several useful applications in all of these areas. Over the years, we have developed or collaborated in developing a strategy that enables researchers to predict the 3D structure of antibodies with a very satisfactory accuracy. The strategy is completely automated and extremely fast, requiring only a few minutes (~10 min on average) to build a structural model of an antibody. It is based on the concept of canonical structures of antibody loops and on our understanding of the way light and heavy chains pack together.

  5. The structure of liquid water; La structure de l'eau liquide

    Energy Technology Data Exchange (ETDEWEB)

    Marin, B [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1969-07-01

    We have tried to expose a bibliography so complete as possible on structure of liquid water. One synthesis of the different models of water structure is presently impossible, so, we have exposed the main properties of water. We have pointed out the new hypotheses on the electronic structure of water molecule and on the theory of hydrogen bond. After that, we have put together the studies of structure by spectroscopy and given the main deductions of some workers on this subject. We have also exposed the characteristics of processes: relaxation and dielectric constant, influence of temperature on structure. At last, we have considered briefly the partition and thermodynamic functions established from the various models proposed. (author) [French] Nous nous sommes proposes d'ecrire une bibliographie aussi complete que possible sur la structure de l'eau liquide. Apres avoir rappele les differentes tentatives d'etablissement de modele de structure, et s'etre rendu compte qu'une synthese s'averait impossible, il nous est apparu souhaitable d'exposer les principales proprietes de l'eau. C'est ainsi que nous avons donne les hypotheses les plus recentes sur la structure electronique de la molecule d'eau ainsi que celles concernant la theorie de la liaison hydrogene. Puis nous avons rassemble les etudes de structure par spectroscopie et fourni les deductions auxquelles les divers auteurs sont arrives. Nous avons egalement expose les caracteristiques des processus tels que: relaxation et constante dielectrique, l'influence de la temperature sur la structure et enfin nous avons donne brievement les fonctions de partition et les grandeurs thermodynamiques etablies a partir des divers modeles proposes. (auteur)

  6. Cell packing structures

    KAUST Repository

    Pottmann, Helmut

    2015-03-03

    This paper is an overview of architectural structures which are either composed of polyhedral cells or closely related to them. We introduce the concept of a support structure of such a polyhedral cell packing. It is formed by planar quads and obtained by connecting corresponding vertices in two combinatorially equivalent meshes whose corresponding edges are coplanar and thus determine planar quads. Since corresponding triangle meshes only yield trivial structures, we focus on support structures associated with quad meshes or hex-dominant meshes. For the quadrilateral case, we provide a short survey of recent research which reveals beautiful relations to discrete differential geometry. Those are essential for successfully initializing numerical optimization schemes for the computation of quad-based support structures. Hex-dominant structures may be designed via Voronoi tessellations, power diagrams, sphere packings and various extensions of these concepts. Apart from the obvious application as load-bearing structures, we illustrate here a new application to shading and indirect lighting. On a higher level, our work emphasizes the interplay between geometry, optimization, statics, and manufacturing, with the overall aim of combining form, function and fabrication into novel integrated design tools.

  7. L'établissement rural des ixe-xe siècles des “ Jeanrais ” à Saint-Prix (Allier The 9th-10th century rural establishment of “Jeanrais” at Saint-Prix (Allier

    Directory of Open Access Journals (Sweden)

    Sophie Liegard

    2011-04-01

    Full Text Available Le site des “ Jeanrais ” a été découvert en 1999 lors du diagnostic préalable à l'aménagement du contournement routier de Lapalisse/Saint-Prix par la route nationale 7. La fouille préventive conduite en 2003 a permis d'étudier près de 4000 m2 de ce vaste établissement rural d'époque carolingienne qui se prolonge de part et d'autre de l'emprise routière et dont l'occupation s'étend sur au moins deux siècles. Les vestiges mis au jour témoignent d'une organisation rigoureuse de l'espace qui ne trouve pas de parallèle régionalement. Le bon état de conservation des vestiges a permis l'identification de plusieurs plans de bâtiments sur poteaux dont un qui abritait un aménagement semi-excavé de plan en “ U ”. Le mobilier recueilli comprend des éléments peu communs tels que des ratés de cuisson de céramique glaçurée et du mobilier équestre. L'ensemble des données recueillies dans les deux zones successives d'occupation révèle des caractéristiques inhabituelles qui conduisent à s'interroger sur le statut de cette implantation.The site of “Jeanrais” was discovered in 1999 during the diagnosis preliminary to the construction of a bypass for Lapalisse/Saint-Prix by trunk road N7. The rescue dig carried out in 2003 was used to study near to 4000 m² of this vast rural settlement of the Carolingian period which extends on either side of the road expropriation and whose occupation spans at least two centuries. The remains uncovered evidence of meticulous organization of space that has no regional parallel. The good state of preservation of the remains has led to the identification of several plans of post buildings one of which housed a semi-excavated development in the shape of a “U”. The collected furnishings include items such as unusual glazed ceramic firing failures and some horse fittings. The data collected in the two successive zones of occupation reveal unusual features which raise questions about

  8. Extended icosahedral structures

    CERN Document Server

    Jaric, Marko V

    1989-01-01

    Extended Icosahedral Structures discusses the concepts about crystal structures with extended icosahedral symmetry. This book is organized into six chapters that focus on actual modeling of extended icosahedral crystal structures. This text first presents a tiling approach to the modeling of icosahedral quasiperiodic crystals. It then describes the models for icosahedral alloys based on random connections between icosahedral units, with particular emphasis on diffraction properties. Other chapters examine the glassy structures with only icosahedral orientational order and the extent of tra

  9. Protein structure recognition: From eigenvector analysis to structural threading method

    Science.gov (United States)

    Cao, Haibo

    In this work, we try to understand the protein folding problem using pair-wise hydrophobic interaction as the dominant interaction for the protein folding process. We found a strong correlation between amino acid sequence and the corresponding native structure of the protein. Some applications of this correlation were discussed in this dissertation include the domain partition and a new structural threading method as well as the performance of this method in the CASP5 competition. In the first part, we give a brief introduction to the protein folding problem. Some essential knowledge and progress from other research groups was discussed. This part include discussions of interactions among amino acids residues, lattice HP model, and the designablity principle. In the second part, we try to establish the correlation between amino acid sequence and the corresponding native structure of the protein. This correlation was observed in our eigenvector study of protein contact matrix. We believe the correlation is universal, thus it can be used in automatic partition of protein structures into folding domains. In the third part, we discuss a threading method based on the correlation between amino acid sequence and ominant eigenvector of the structure contact-matrix. A mathematically straightforward iteration scheme provides a self-consistent optimum global sequence-structure alignment. The computational efficiency of this method makes it possible to search whole protein structure databases for structural homology without relying on sequence similarity. The sensitivity and specificity of this method is discussed, along with a case of blind test prediction. In the appendix, we list the overall performance of this threading method in CASP5 blind test in comparison with other existing approaches.

  10. Protein Structure Recognition: From Eigenvector Analysis to Structural Threading Method

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Haibo [Iowa State Univ., Ames, IA (United States)

    2003-01-01

    In this work, they try to understand the protein folding problem using pair-wise hydrophobic interaction as the dominant interaction for the protein folding process. They found a strong correlation between amino acid sequences and the corresponding native structure of the protein. Some applications of this correlation were discussed in this dissertation include the domain partition and a new structural threading method as well as the performance of this method in the CASP5 competition. In the first part, they give a brief introduction to the protein folding problem. Some essential knowledge and progress from other research groups was discussed. This part includes discussions of interactions among amino acids residues, lattice HP model, and the design ability principle. In the second part, they try to establish the correlation between amino acid sequence and the corresponding native structure of the protein. This correlation was observed in the eigenvector study of protein contact matrix. They believe the correlation is universal, thus it can be used in automatic partition of protein structures into folding domains. In the third part, they discuss a threading method based on the correlation between amino acid sequences and ominant eigenvector of the structure contact-matrix. A mathematically straightforward iteration scheme provides a self-consistent optimum global sequence-structure alignment. The computational efficiency of this method makes it possible to search whole protein structure databases for structural homology without relying on sequence similarity. The sensitivity and specificity of this method is discussed, along with a case of blind test prediction. In the appendix, they list the overall performance of this threading method in CASP5 blind test in comparison with other existing approaches.

  11. Protein Structure Recognition: From Eigenvector Analysis to Structural Threading Method

    International Nuclear Information System (INIS)

    Haibo Cao

    2003-01-01

    In this work, they try to understand the protein folding problem using pair-wise hydrophobic interaction as the dominant interaction for the protein folding process. They found a strong correlation between amino acid sequences and the corresponding native structure of the protein. Some applications of this correlation were discussed in this dissertation include the domain partition and a new structural threading method as well as the performance of this method in the CASP5 competition. In the first part, they give a brief introduction to the protein folding problem. Some essential knowledge and progress from other research groups was discussed. This part includes discussions of interactions among amino acids residues, lattice HP model, and the design ability principle. In the second part, they try to establish the correlation between amino acid sequence and the corresponding native structure of the protein. This correlation was observed in the eigenvector study of protein contact matrix. They believe the correlation is universal, thus it can be used in automatic partition of protein structures into folding domains. In the third part, they discuss a threading method based on the correlation between amino acid sequences and ominant eigenvector of the structure contact-matrix. A mathematically straightforward iteration scheme provides a self-consistent optimum global sequence-structure alignment. The computational efficiency of this method makes it possible to search whole protein structure databases for structural homology without relying on sequence similarity. The sensitivity and specificity of this method is discussed, along with a case of blind test prediction. In the appendix, they list the overall performance of this threading method in CASP5 blind test in comparison with other existing approaches

  12. Structural Biology Fact Sheet

    Science.gov (United States)

    ... NIGMS NIGMS Home > Science Education > Structural Biology Structural Biology Tagline (Optional) Middle/Main Content Area PDF Version (688 KB) Other Fact Sheets What is structural biology? Structural biology is the study of how biological ...

  13. Dynamic Analysis of Partially Embedded Structures Considering Soil-Structure Interaction in Time Domain

    OpenAIRE

    Mahmoudpour, Sanaz; Attarnejad, Reza; Behnia, Cambyse

    2011-01-01

    Analysis and design of structures subjected to arbitrary dynamic loadings especially earthquakes have been studied during past decades. In practice, the effects of soil-structure interaction on the dynamic response of structures are usually neglected. In this study, the effect of soil-structure interaction on the dynamic response of structures has been examined. The substructure method using dynamic stiffness of soil is used to analyze soil-structure system. A coupled model based on finite el...

  14. Protein Structure and the Sequential Structure of mRNA

    DEFF Research Database (Denmark)

    Brunak, Søren; Engelbrecht, Jacob

    1996-01-01

    entries in the Brookhaven Protein Data Bank produced 719 protein chains with matching mRNA sequence, amino acid sequence, and secondary structure assignment, By neural network analysis, we found strong signals in mRNA sequence regions surrounding helices and sheets, These signals do not originate from......A direct comparison of experimentally determined protein structures and their corresponding protein coding mRNA sequences has been performed, We examine whether real world data support the hypothesis that clusters of rare codons correlate with the location of structural units in the resulting...... protein, The degeneracy of the genetic code allows for a biased selection of codons which may control the translational rate of the ribosome, and may thus in vivo have a catalyzing effect on the folding of the polypeptide chain, A complete search for GenBank nucleotide sequences coding for structural...

  15. Component nuclear containment structure

    International Nuclear Information System (INIS)

    Harstead, G.A.

    1979-01-01

    The invention described is intended for use primarily as a nuclear containment structure. Such structures are required to surround the nuclear steam supply system and to contain the effects of breaks in the nuclear steam supply system, or i.e. loss of coolant accidents. Nuclear containment structures are required to withstand internal pressure and temperatures which result from loss of coolant accidents, and to provide for radiation shielding during operation and during the loss of coolant accident, as well as to resist all other applied loads, such as earthquakes. The nuclear containment structure described herein is a composite nuclear containment structure, and is one which structurally combines two previous systems; namely, a steel vessel, and a lined concrete structure. The steel vessel provides strength to resist internal pressure and accommodate temperature increases, the lined concrete structure provides resistance to internal pressure by having a liner which will prevent leakage, and which is in contact with the concrete structure which provides the strength to resist the pressure

  16. Structural building response review

    International Nuclear Information System (INIS)

    1980-01-01

    The integrity of a nuclear power plant during a postulated seismic event is required to protect the public against radiation. Therefore, a detailed set of seismic analyses of various structures and equipment is performed while designing a nuclear power plant. This report describes the structural response analysis method, including the structural model, soil-structure interaction as it relates to structural models, methods for seismic structural analysis, numerical integration methods, methods for non-seismic response analysis approaches for various response combinations, structural damping values, nonlinear response, uncertainties in structural properties, and structural response analysis using random properties. The report describes the state-of-the-art in these areas for nuclear power plants. It also details the past studies made at Sargent and Lundy to evaluate different alternatives and the conclusions reached for the specific purposes that those studies were intended. These results were incorporated here because they fall into the general scope of this report. The scope of the present task does not include performing new calculations

  17. Generalized structured component analysis a component-based approach to structural equation modeling

    CERN Document Server

    Hwang, Heungsun

    2014-01-01

    Winner of the 2015 Sugiyama Meiko Award (Publication Award) of the Behaviormetric Society of Japan Developed by the authors, generalized structured component analysis is an alternative to two longstanding approaches to structural equation modeling: covariance structure analysis and partial least squares path modeling. Generalized structured component analysis allows researchers to evaluate the adequacy of a model as a whole, compare a model to alternative specifications, and conduct complex analyses in a straightforward manner. Generalized Structured Component Analysis: A Component-Based Approach to Structural Equation Modeling provides a detailed account of this novel statistical methodology and its various extensions. The authors present the theoretical underpinnings of generalized structured component analysis and demonstrate how it can be applied to various empirical examples. The book enables quantitative methodologists, applied researchers, and practitioners to grasp the basic concepts behind this new a...

  18. The structure of magnetic materials; La structure des substances magnetiques

    Energy Technology Data Exchange (ETDEWEB)

    Villain, J. [Commissariat a l' energie atomique et aux energies alternatives - CEA, C.E.N. Saclay (France)

    1960-07-01

    The paper deals with the prediction of the structure of magnetic materials below the critical point. The molecular field approximation is used: exchange interactions with unlimited range are assumed; the magnetic ions are supposed to form a Bravais lattice. The critical temperature T{sub c} is first calculated (section 1) without assuming any decomposition of the crystal into sublattices, and the magnetic structure at T{sub c} is given. It is next shown (section 2) that the essential features of this structure persist below T{sub c}, and the various possible cases are considered. It is possible that no decomposition into sublattices takes place, i.e. the magnetic structure and the nuclear structure have incommensurable periods. A detailed treatment is then given for the body-centered quadratic lattice (section 3) with interaction between first, second and third neighbours. Reprint of a paper published in Journal of Physical Chemistry, vol. 11, no. 3/4, p. 303-309, 1959 [French] Ce travail a pour objet la prevision systematique de la structure des substances magnetiques au-dessous du point de transition et l'etude des differents cas qui peuvent se presenter lorsque les ions magnetiques forment un reseau de Bravais. On se place dans une approximation de champ moleculaire, mais on ne fait aucune restriction concernant la portee des interactions d'echange. Apres avoir determine (Section 1) la temperature critique et la structure magnetique a cette temperature sans supposer a priori l'existence d'une decomposition en sous-reseaux, on montre (Section 2) que cette structure reste stable en dessous de la temperature critique, et on etudie les divers cas possibles. Il peut arriver en particulier que la structure magnetique ait une periode incommensurable avec celle du reseau cristallin. L'example du reseau quadratique centre avec couplage entre premiers, seconds et troisiemes voisins (Section 3) fournit une bonne illustration de cette etude. Reproduction d'un article publie

  19. Structural classification and a binary structure model for superconductors

    Institute of Scientific and Technical Information of China (English)

    Dong Cheng

    2006-01-01

    Based on structural and bonding features, a new classification scheme of superconductors is proposed to classify conductors can be partitioned into two parts, a superconducting active component and a supplementary component.Partially metallic covalent bonding is found to be a common feature in all superconducting active components, and the electron states of the atoms in the active components usually make a dominant contribution to the energy band near the Fermi surface. Possible directions to explore new superconductors are discussed based on the structural classification and the binary structure model.

  20. Integrated materials–structural models

    DEFF Research Database (Denmark)

    Stang, Henrik; Geiker, Mette Rica

    2008-01-01

    , repair works and strengthening methods for structures. A very significant part of the infrastructure consists of reinforced concrete structures. Even though reinforced concrete structures typically are very competitive, certain concrete structures suffer from various types of degradation. A framework...... should define a framework in which materials research results eventually should fit in and on the other side the materials research should define needs and capabilities in structural modelling. Integrated materials-structural models of a general nature are almost non-existent in the field of cement based...

  1. Trajectory grouping structure

    Directory of Open Access Journals (Sweden)

    Maike Buchin

    2015-03-01

    Full Text Available The collective motion of a set of moving entities like people, birds, or other animals, is characterized by groups arising, merging, splitting, and ending. Given the trajectories of these entities, we define and model a structure that captures all of such changes using the Reeb graph, a concept from topology. The trajectory grouping structure has three natural parameters that allow more global views of the data in group size, group duration, and entity inter-distance. We prove complexity bounds on the maximum number of maximal groups that can be present, and give algorithms to compute the grouping structure efficiently. We also study how the trajectory grouping structure can be made robust, that is, how brief interruptions of groups can be disregarded in the global structure, adding a notion of persistence to the structure. Furthermore, we showcase the results of experiments using data generated by the NetLogo flocking model and from the Starkey project. The Starkey data describe the movement of elk, deer, and cattle. Although there is no ground truth for the grouping structure in this data, the experiments show that the trajectory grouping structure is plausible and has the desired effects when changing the essential parameters. Our research provides the first complete study of trajectory group evolvement, including combinatorial,algorithmic, and experimental results.

  2. Structural and optical properties of solid-state synthesized Au dendritic structures

    International Nuclear Information System (INIS)

    Gentile, A.; Ruffino, F.; Romano, L.; Boninelli, S.; Reitano, R.; Piccitto, G.; Grimaldi, M.G.

    2014-01-01

    Graphical abstract: - Highlights: • Au dendritic structures were produced on surfaces. • The chemical and structural properties of the dendritic structures are presented. • The optical properties of the dendritic structures are presented. • The ability of the dendritic structures to serve as light scattering centers is presented. - Abstract: Au dendrites (Au Ds) are synthesized, on various substrates, by a simple physical methodology involving the deposition of a thin Au film on a Si surface followed by thermal processes at high temperatures (>1273 K) in an inert ambient (N 2 ), using fast heating and cooling rates (1273 K/min). Microscopic analyses reveal the evolution, thanks to the thermal processes, of the Au film from a continuous coating to dendritic structures covering the entire sample surface. In particular, transmission electron microscopy analyses indicate that, below the Au surface, the dendritic structures consist of Si atoms originating from the substrate. Furthermore, optical characterizations reveal the ability of the Au Ds to serve as scattering centers in the infrared region. Finally, on the basis of the experimental observations, a phenomenological model for the growth of the Au Ds is proposed

  3. Structural and Topology Optimization of Complex Civil Engineering Structures

    DEFF Research Database (Denmark)

    Hald, Frederik; Kirkegaard, Poul Henning; Andersen, Lars Vabbersgaard

    2013-01-01

    This paper shows the use of topology optimization for finding an optimized form for civil engineering structures. Today topology optimization and shape optimization have been integrated in several commercial finite element codes. Here, the topology of two complex civil engineering structures...

  4. MicroRNA-target binding structures mimic microRNA duplex structures in humans.

    Directory of Open Access Journals (Sweden)

    Xi Chen

    Full Text Available Traditionally, researchers match a microRNA guide strand to mRNA sequences using sequence comparisons to predict its potential target genes. However, many of the predictions can be false positives due to limitations in sequence comparison alone. In this work, we consider the association of two related RNA structures that share a common guide strand: the microRNA duplex and the microRNA-target binding structure. We have analyzed thousands of such structure pairs and found many of them share high structural similarity. Therefore, we conclude that when predicting microRNA target genes, considering just the microRNA guide strand matches to gene sequences may not be sufficient--the microRNA duplex structure formed by the guide strand and its companion passenger strand must also be considered. We have developed software to translate RNA binding structure into encoded representations, and we have also created novel automatic comparison methods utilizing such encoded representations to determine RNA structure similarity. Our software and methods can be utilized in the other RNA secondary structure comparisons as well.

  5. Uncertainty Quantification in Experimental Structural Dynamics Identification of Composite Material Structures

    DEFF Research Database (Denmark)

    Luczak, Marcin; Peeters, Bart; Kahsin, Maciej

    2014-01-01

    for uncertainty evaluation in experimentally estimated models. Investigated structures are plates, fuselage panels and helicopter main rotor blades as they represent different complexity levels ranging from coupon, through sub-component up to fully assembled structures made of composite materials. To evaluate......Aerospace and wind energy structures are extensively using components made of composite materials. Since these structures are subjected to dynamic environments with time-varying loading conditions, it is important to model their dynamic behavior and validate these models by means of vibration...

  6. Nuclear structure theory

    CERN Document Server

    Irvine, J M

    1972-01-01

    Nuclear Structure Theory provides a guide to nuclear structure theory. The book is comprised of 23 chapters that are organized into four parts; each part covers an aspect of nuclear structure theory. In the first part, the text discusses the experimentally observed phenomena, which nuclear structure theories need to look into and detail the information that supports those theories. The second part of the book deals with the phenomenological nucleon-nucleon potentials derived from phase shift analysis of nucleon-nucleon scattering. Part III talks about the phenomenological parameters used to de

  7. Unpolarized Structure Functions

    International Nuclear Information System (INIS)

    Christy, M.E.; Melnitchouk, W.

    2011-01-01

    Over the past decade measurements of unpolarized structure functions with unprecedented precision have significantly advanced our knowledge of nucleon structure. These have for the first time allowed quantitative tests of the phenomenon of quark-hadron duality, and provided a deeper understanding of the transition from hadron to quark degrees of freedom in inclusive scattering. Dedicated Rosenbluth-separation experiments have yielded high-precision transverse and longitudinal structure functions in regions previously unexplored, and new techniques have enabled the first glimpses of the structure of the free neutron, without contamination from nuclear effects.

  8. Structure and stoichiometry

    International Nuclear Information System (INIS)

    Gai, P.L.

    1992-01-01

    Structural and stoichiometric variations and their role in superconducting properties of bulk cuprate ceramics are elucidated. Atomic structure and chemistry of defect microstructures, including vacancy and interstitial defects, weak-link problems, structural modulations and coherent intergrowths leading to new structures are studies and quantitatively interpreted. They are shown to play a critical role in controlling hole concentration, critical currents and flux pinning. These phenomena underpin the solid state chemistry which determines the physical properties of the nonstoichiometric oxide superconductors. In this paper technological implications, synthesis of related novel materials and recent developments are discussed

  9. Linguistic Structure Prediction

    CERN Document Server

    Smith, Noah A

    2011-01-01

    A major part of natural language processing now depends on the use of text data to build linguistic analyzers. We consider statistical, computational approaches to modeling linguistic structure. We seek to unify across many approaches and many kinds of linguistic structures. Assuming a basic understanding of natural language processing and/or machine learning, we seek to bridge the gap between the two fields. Approaches to decoding (i.e., carrying out linguistic structure prediction) and supervised and unsupervised learning of models that predict discrete structures as outputs are the focus. W

  10. Machine tool structures

    CERN Document Server

    Koenigsberger, F

    1970-01-01

    Machine Tool Structures, Volume 1 deals with fundamental theories and calculation methods for machine tool structures. Experimental investigations into stiffness are discussed, along with the application of the results to the design of machine tool structures. Topics covered range from static and dynamic stiffness to chatter in metal cutting, stability in machine tools, and deformations of machine tool structures. This volume is divided into three sections and opens with a discussion on stiffness specifications and the effect of stiffness on the behavior of the machine under forced vibration c

  11. Structural pounding of concrete frame structure with masonry infill wall under seismic loading

    Science.gov (United States)

    Ismail, Rozaina; Hasnan, Mohd Hafizudin; Shamsudin, Nurhanis

    2017-10-01

    Structural pounding is additional problem than the other harmful damage that may occurs due to the earthquake vibrations. A lot of study has been made by past researcher but most of them did not include the walls. The infill masonry walls are rarely involved analysis of structural systems but it does contribute to earthquake response of the structures. In this research, a comparison between adjacent building of 10-storey and 7-storey concrete frame structure without of masonry infill walls and the same dynamic properties of buildings. The diagonal strut approach is adopted for modeling masonry infill walls. This research also focused on finding critical building separation in order to prevent the adjacent structures from pounding. LUSAS FEA v14.03 software has been used for modeling analyzing the behavior of structures due to seismic loading and the displacement each floor of the building has been taken in order to determine the critical separation distance between the buildings. From the analysis that has been done, it is found that masonry infill walls do affect the structures behavior under seismic load. Structures without masonry infill walls needs more distance between the structures to prevent structural pounding due to higher displacement of the buildings when it sways under seismic load compared to structures with masonry infill walls. This shows that contribution of masonry infill walls to the analysis of structures cannot be neglected.

  12. Multi-structure docking analysis of BACE1 crystal structures and non-peptidic ligands.

    Science.gov (United States)

    Haghighijoo, Zahra; Hemmateenejad, Bahram; Edraki, Najmeh; Miri, Ramin; Emami, Saeed

    2017-09-01

    In order to design novel non-peptidic inhibitors of BACE1, many research groups have attempted using computational studies including docking analyses. Since there are too many 3D structures for BACE1 in the protein database, the selection of suitable crystal structures is a key prerequisite for the successful application of molecular docking. We employed a multi-structure docking protocol. In which 615 ligands' structures were docked into 150 BACE1 structures. The large number of the resultant docking scores were post-processed by different data analysis methods including exploratory data analysis, regression analysis and discriminant analysis. It was found that using one crystal structure for docking did not result in high accuracy for predicting activity of the BACE1 inhibitors. Instead, using of the multi-structural docking scores, post-processed by chemometrics methods arrived to highly accurate predictive models. In this regards, the PDB accession codes of 4B70, 4DVF and 2WEZ could discriminate between active and inactive compounds, with higher accuracy. Clustering of the BACE1 structures based on principal component analysis of the crystallographic structures the revealed that the discriminant structures are in the center of the clusters. Thus, these structures can be selected as predominant crystal structures for docking studies of non-peptidic BACE1 inhibitors. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Structural morphology of zinc oxide structures with antibacterial application of calamine lotion

    Energy Technology Data Exchange (ETDEWEB)

    Ann, Ling Chuo; Mahmud, Shahrom; Bakhori, Siti Khadijah Mohd; Sirelkhatim, Amna [Nano-optoelectronic Research (NOR) Laboratory, School of Physics, Universiti Sains Malaysia 11800 Pulau Pinang (Malaysia); Mohamad, Dasmawati [School of Dental Sciences, Universiti Sains Malaysia, Kubang Kerian 16150 Kelantan (Malaysia); Hasan, Habsah; Rahman, Rosliza Abdul [School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian 16150 Kelantan (Malaysia); Seeni, Azman [Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam 13200 Pulau Pinang (Malaysia)

    2015-04-24

    In this study, we report the structural morphology of a zinc oxide (ZnO) sample and antibacterial application of the ZnO structures in calamine lotion. Antibacterial activities of the calamine lotion towards Staphylococcus aureus and Pseudomonas aeruginosa were investigated. The structural morphology of ZnO sample was studied using a transmission electron microscope (TEM) and a field-emission scanning electron microscope (FESEM). The morphologies of the ZnO structure consisted of many rod and spherical structures. The particle sizes of the sample ranged from 40 nm to 150 nm. A calamine lotion was prepared through mixing the ZnO structures with other constituents in suitable proportion. The energy-dispersive x-ray spectroscopy (EDS) revealed the presence of large amount of ZnO structures whiles the X-ray diffraction (XRD) results showed a good crystalline property of ZnO in the calamine lotion mixture. The morphological structures of ZnO were found to remain unchanged in the calamine lotion mixture through FESEM imaging. In the antibacterial test, prepared calamine lotion exhibited a remarkable bacterial inhibition on Staphylococcus aureus and Pseudomonas aeruginosa after 24 h of treatment. The bactericidal capability of calamine lotion was largely due to the presence of ZnO structures which induce high toxicity and killing effect on the bacteria.

  14. Structural morphology of zinc oxide structures with antibacterial application of calamine lotion

    International Nuclear Information System (INIS)

    Ann, Ling Chuo; Mahmud, Shahrom; Bakhori, Siti Khadijah Mohd; Sirelkhatim, Amna; Mohamad, Dasmawati; Hasan, Habsah; Rahman, Rosliza Abdul; Seeni, Azman

    2015-01-01

    In this study, we report the structural morphology of a zinc oxide (ZnO) sample and antibacterial application of the ZnO structures in calamine lotion. Antibacterial activities of the calamine lotion towards Staphylococcus aureus and Pseudomonas aeruginosa were investigated. The structural morphology of ZnO sample was studied using a transmission electron microscope (TEM) and a field-emission scanning electron microscope (FESEM). The morphologies of the ZnO structure consisted of many rod and spherical structures. The particle sizes of the sample ranged from 40 nm to 150 nm. A calamine lotion was prepared through mixing the ZnO structures with other constituents in suitable proportion. The energy-dispersive x-ray spectroscopy (EDS) revealed the presence of large amount of ZnO structures whiles the X-ray diffraction (XRD) results showed a good crystalline property of ZnO in the calamine lotion mixture. The morphological structures of ZnO were found to remain unchanged in the calamine lotion mixture through FESEM imaging. In the antibacterial test, prepared calamine lotion exhibited a remarkable bacterial inhibition on Staphylococcus aureus and Pseudomonas aeruginosa after 24 h of treatment. The bactericidal capability of calamine lotion was largely due to the presence of ZnO structures which induce high toxicity and killing effect on the bacteria

  15. The Structural Integrity Centre

    International Nuclear Information System (INIS)

    Tomkins, B.

    1987-01-01

    The paper concerns the development and work of the Structural Integrity Centre (SIC) at Risley Nuclear Laboratories, United Kingdom. The centre was set up to provide authoritative advice to plant designers and operators on the integrity and life assessment of structures and components across the reactor projects in the United Kingdom. A description is given of the structure and role of the SIC, as well as the Structural Integrity Assessment work. The assessment methods are described for thermally loaded structures and welded structures. Finally, defect significance assessment and environmental effects are outlined. (U.K.)

  16. Band structure of semiconductors

    CERN Document Server

    Tsidilkovski, I M

    2013-01-01

    Band Structure of Semiconductors provides a review of the theoretical and experimental methods of investigating band structure and an analysis of the results of the developments in this field. The book presents the problems, methods, and applications in the study of band structure. Topics on the computational methods of band structure; band structures of important semiconducting materials; behavior of an electron in a perturbed periodic field; effective masses and g-factors for the most commonly encountered band structures; and the treatment of cyclotron resonance, Shubnikov-de Haas oscillatio

  17. HIV Structural Database

    Science.gov (United States)

    SRD 102 HIV Structural Database (Web, free access)   The HIV Protease Structural Database is an archive of experimentally determined 3-D structures of Human Immunodeficiency Virus 1 (HIV-1), Human Immunodeficiency Virus 2 (HIV-2) and Simian Immunodeficiency Virus (SIV) Proteases and their complexes with inhibitors or products of substrate cleavage.

  18. Growing Timber Structures

    DEFF Research Database (Denmark)

    Tamke, Martin; Evers, Henrik Leander; Stasiuk, David

    2013-01-01

    The contemporary design of timber structures has to answer questions concerning structural stability, production impact and energy implications in ever earlier stages. The interrelation of these levels creates a complexity that is difficult to resolve through contemporary linear parametric...... to integrate the behaviour of networked systems into structures made from wooden material....

  19. Multi-functional composite structures

    Science.gov (United States)

    Mulligan, Anthony C.; Halloran, John; Popovich, Dragan; Rigali, Mark J.; Sutaria, Manish P.; Vaidyanathan, K. Ranji; Fulcher, Michael L.; Knittel, Kenneth L.

    2004-10-19

    Fibrous monolith processing techniques to fabricate multifunctional structures capable of performing more than one discrete function such as structures capable of bearing structural loads and mechanical stresses in service and also capable of performing at least one additional non-structural function.

  20. Antibody structural modeling with prediction of immunoglobulin structure (PIGS)

    KAUST Repository

    Marcatili, Paolo; Olimpieri, Pier Paolo; Chailyan, Anna; Tramontano, Anna

    2014-01-01

    of antibodies with a very satisfactory accuracy. The strategy is completely automated and extremely fast, requiring only a few minutes (~10 min on average) to build a structural model of an antibody. It is based on the concept of canonical structures of antibody

  1. Capital Structure Determinants and Governance Structure Variety in Franchising

    NARCIS (Netherlands)

    T. Jiang (Tao)

    2009-01-01

    textabstractThis thesis investigates two questions: the determinants of capital structure in franchising and its subsequent impact on the franchise financing decisions; and the efficient governance structure choice in franchising. We posit that firms franchise in order to benefit from the reduced

  2. Robustness of structures

    DEFF Research Database (Denmark)

    Vrouwenvelder, T.; Sørensen, John Dalsgaard

    2009-01-01

    After the collapse of the World Trade Centre towers in 2001 and a number of collapses of structural systems in the beginning of the century, robustness of structural systems has gained renewed interest. Despite many significant theoretical, methodical and technological advances, structural...... of robustness for structural design such requirements are not substantiated in more detail, nor have the engineering profession been able to agree on an interpretation of robustness which facilitates for its uantification. A European COST action TU 601 on ‘Robustness of structures' has started in 2007...... by a group of members of the CSS. This paper describes the ongoing work in this action, with emphasis on the development of a theoretical and risk based quantification and optimization procedure on the one side and a practical pre-normative guideline on the other....

  3. Design and analysis of composite structures with applications to aerospace structures

    CERN Document Server

    Kassapoglou, Christos

    2010-01-01

    Design and Analysis of Composite Structures enables graduate students and engineers to generate meaningful and robust designs of complex composite structures. Combining analysis and design methods for structural components, the book begins with simple topics such as skins and stiffeners and progresses through to entire components of fuselages and wings. Starting with basic mathematical derivation followed by simplifications used in real-world design, Design and Analysis of Composite Structures presents the level of accuracy and range of applicability of each method. Examples taken from ac

  4. Structural integrity of graphite core support structures of HTTR

    International Nuclear Information System (INIS)

    Inagaki, Yoshiyuki; Iyoku, Tatsuo; Toyota, Junji; Sato, Sadao; Shiozawa, Shusaku

    1990-02-01

    The graphite core support structures (GCSSs) of the HTTR (High Temperature Engineering Test Reactor) are an arrangement of graphite blocks and posts that support the core and provide a lower plenum and a hot-leg path for the primary coolant. The GCSSs are designed not to be replaced by new items during plant life time (about twenty years). To maintain structural integrity of the GCSSs, conservative design has been made sufficiently on the basis of structural tests. The present study confirmed that reactor safety was still maintained even if failure and destruction of the GCSSs is supposed to occur. The GCSSs are fabricated under strict quality control and the observation and surveillance programs are planed to examine the structual integrity of the GCSSs during an operation. This paper describes the concept of design and quality control and summarizes structural tests, observation and surveillance programs. (author)

  5. Choice of rational structural solution for smart innovative suspension structure

    Science.gov (United States)

    Goremikins, V.; Serdjuks, D.; Buka-Vaivade, K.; Pakrastins, L.

    2017-10-01

    Choice of the rational structural solution for smart innovative suspension structure was carried out. The prestressed cable trusses and cross-laminated timber panels were considered as the main load bearing members for the smart innovative suspension structure. The FEM model, which enables to predict behaviours of the structure, was developed in the programme ANSYS v12. Structural solutions that are differed by the lattice configuration of the cable truss and placement of cross-laminated timber panels were considered. The variant of the cable truss with the vertical suspenders and chords joined in the middle of the span was chosen as the best one. It was shown, that placement of cross-laminated timber panels by the bottom chord of the prestressed cable truss enables to decrease materials consumption by 16.7% in comparison with the variant, where the panels are placed by the top chord. It was stated, that the materials consumption decrease by 17.3% in the case, when common work of the prestressed cable trusses and cross-laminated timber panels is taken into account. The cross-laminated timber panels are working in the both directions. Physical model of the structure with the span equal to 2 m was developed for checking of numerically obtained results.

  6. On topological RNA interaction structures.

    Science.gov (United States)

    Qin, Jing; Reidys, Christian M

    2013-07-01

    Recently a folding algorithm of topological RNA pseudoknot structures was presented in Reidys et al. (2011). This algorithm folds single-stranded γ-structures, that is, RNA structures composed by distinct motifs of bounded topological genus. In this article, we set the theoretical foundations for the folding of the two backbone analogues of γ structures: the RNA γ-interaction structures. These are RNA-RNA interaction structures that are constructed by a finite number of building blocks over two backbones having genus at most γ. Combinatorial properties of γ-interaction structures are of practical interest since they have direct implications for the folding of topological interaction structures. We compute the generating function of γ-interaction structures and show that it is algebraic, which implies that the numbers of interaction structures can be computed recursively. We obtain simple asymptotic formulas for 0- and 1-interaction structures. The simplest class of interaction structures are the 0-interaction structures, which represent the two backbone analogues of secondary structures.

  7. Exotic cluster structures on

    CERN Document Server

    Gekhtman, M; Vainshtein, A

    2017-01-01

    This is the second paper in the series of papers dedicated to the study of natural cluster structures in the rings of regular functions on simple complex Lie groups and Poisson-Lie structures compatible with these cluster structures. According to our main conjecture, each class in the Belavin-Drinfeld classification of Poisson-Lie structures on \\mathcal{G} corresponds to a cluster structure in \\mathcal{O}(\\mathcal{G}). The authors have shown before that this conjecture holds for any \\mathcal{G} in the case of the standard Poisson-Lie structure and for all Belavin-Drinfeld classes in SL_n, n<5. In this paper the authors establish it for the Cremmer-Gervais Poisson-Lie structure on SL_n, which is the least similar to the standard one.

  8. Structural realism beyond physics.

    Science.gov (United States)

    Tulodziecki, Dana

    2016-10-01

    The main purpose of this paper is to test structural realism against (one example from) the historical record. I begin by laying out an existing challenge to structural realism - that of providing an example of a theory exhibiting successful structures that were abandoned - and show that this challenge can be met by the miasma theory of disease. However, rather than concluding that this is an outright counterexample to structural realism, I use this case to show why it is that structural realism, in its current form, has trouble dealing with theories outside physics. I end by making some concrete suggestions for structural realists to pursue if, indeed, they are serious about extending structural realism to other domains. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Encounters with Structure

    Science.gov (United States)

    Connell, R. W.

    2004-01-01

    A discussion of poststructuralism may be helped by reflecting on the trajectory of ideas and practices that produced it. Structuralism as an intellectual movement has had a bad press and doubtless some of that is deserved. But structuralism was more diverse and creative, and structural analysis as a procedure in social science is more important,…

  10. Structural patterns in nature

    DEFF Research Database (Denmark)

    Wester, Ture

    2003-01-01

    be an inspiration to structural morphologists and other dealing with the shaping of structures for buildings and other objects. Often the patterns appear in "dual" materializations, which indicate two radically different structural types of action. Randomness as a generator for optimal and basic structural action...

  11. Structural patterns in nature

    DEFF Research Database (Denmark)

    Wester, Ture

    2004-01-01

    be an inspiration to structural morphologists and other dealing with the shaping of structures for buildings and other objects. Often the patterns appear in "dual" materializations, which indicate two radically different structural types of action. Randomness as a generator for optimal and basic structural action...

  12. A study on soil structure

    NARCIS (Netherlands)

    Schuylenborgh, van J.

    1947-01-01

    As soils differ in capacity to form a structure, it is necessary to distinguish between intrinsic structure and actual structure. Intrinsic structure is the capacity of a soil to form a certain structure. Actual structure is the structure of the soil at a certain moment.

    Using experiments and

  13. Category I structures program

    International Nuclear Information System (INIS)

    Endebrock, E.G.; Dove, R.C.

    1981-01-01

    The objective of the Category I Structure Program is to supply experimental and analytical information needed to assess the structural capacity of Category I structures (excluding the reactor cntainment building). Because the shear wall is a principal element of a Category I structure, and because relatively little experimental information is available on the shear walls, it was selected as the test element for the experimental program. The large load capacities of shear walls in Category I structures dictates that the experimental tests be conducted on small size shear wall structures that incorporates the general construction details and characteristics of as-built shear walls

  14. Probabilistic Structural Analysis Methods (PSAM) for select space propulsion system structural components

    Science.gov (United States)

    Cruse, T. A.

    1987-01-01

    The objective is the development of several modular structural analysis packages capable of predicting the probabilistic response distribution for key structural variables such as maximum stress, natural frequencies, transient response, etc. The structural analysis packages are to include stochastic modeling of loads, material properties, geometry (tolerances), and boundary conditions. The solution is to be in terms of the cumulative probability of exceedance distribution (CDF) and confidence bounds. Two methods of probability modeling are to be included as well as three types of structural models - probabilistic finite-element method (PFEM); probabilistic approximate analysis methods (PAAM); and probabilistic boundary element methods (PBEM). The purpose in doing probabilistic structural analysis is to provide the designer with a more realistic ability to assess the importance of uncertainty in the response of a high performance structure. Probabilistic Structural Analysis Method (PSAM) tools will estimate structural safety and reliability, while providing the engineer with information on the confidence that should be given to the predicted behavior. Perhaps most critically, the PSAM results will directly provide information on the sensitivity of the design response to those variables which are seen to be uncertain.

  15. Probabilistic Structural Analysis Methods for select space propulsion system structural components (PSAM)

    Science.gov (United States)

    Cruse, T. A.; Burnside, O. H.; Wu, Y.-T.; Polch, E. Z.; Dias, J. B.

    1988-01-01

    The objective is the development of several modular structural analysis packages capable of predicting the probabilistic response distribution for key structural variables such as maximum stress, natural frequencies, transient response, etc. The structural analysis packages are to include stochastic modeling of loads, material properties, geometry (tolerances), and boundary conditions. The solution is to be in terms of the cumulative probability of exceedance distribution (CDF) and confidence bounds. Two methods of probability modeling are to be included as well as three types of structural models - probabilistic finite-element method (PFEM); probabilistic approximate analysis methods (PAAM); and probabilistic boundary element methods (PBEM). The purpose in doing probabilistic structural analysis is to provide the designer with a more realistic ability to assess the importance of uncertainty in the response of a high performance structure. Probabilistic Structural Analysis Method (PSAM) tools will estimate structural safety and reliability, while providing the engineer with information on the confidence that should be given to the predicted behavior. Perhaps most critically, the PSAM results will directly provide information on the sensitivity of the design response to those variables which are seen to be uncertain.

  16. Organisational Structure

    Science.gov (United States)

    National Centre for Vocational Education Research (NCVER), 2006

    2006-01-01

    An understanding of organisational structure can provide guidance for organisations that want to change and innovate. Many writers agree that this understanding allows organisations to shape how their work is done to ultimately achieve their business goals--and that too often structure is given little consideration in business strategy and…

  17. Structural analysis of β-glucosidase mutants derived from a hyperthermophilic tetrameric structure

    International Nuclear Information System (INIS)

    Nakabayashi, Makoto; Kataoka, Misumi; Mishima, Yumiko; Maeno, Yuka; Ishikawa, Kazuhiko

    2014-01-01

    Substitutive mutations that convert a tetrameric β-glucosidase into a dimeric state lead to improvement of its crystal quality. β-Glucosidase from Pyrococcus furiosus (BGLPf) is a hyperthermophilic tetrameric enzyme which can degrade cellooligosaccharides to glucose under hyperthermophilic conditions and thus holds promise for the saccharification of lignocellulosic biomass at high temperature. Prior to the production of large amounts of this enzyme, detailed information regarding the oligomeric structure of the enzyme is required. Several crystals of BGLPf have been prepared over the past ten years, but its crystal structure had not been solved until recently. In 2011, the first crystal structure of BGLPf was solved and a model was constructed at somewhat low resolution (2.35 Å). In order to obtain more detailed structural data on BGLPf, the relationship between its tetrameric structure and the quality of the crystal was re-examined. A dimeric form of BGLPf was constructed and its crystal structure was solved at a resolution of 1.70 Å using protein-engineering methods. Furthermore, using the high-resolution crystal structural data for the dimeric form, a monomeric form of BGLPf was constructed which retained the intrinsic activity of the tetrameric form. The thermostability of BGLPf is affected by its oligomeric structure. Here, the biophysical and biochemical properties of engineered dimeric and monomeric BGLPfs are reported, which are promising prototype models to apply to the saccharification reaction. Furthermore, details regarding the oligomeric structures of BGLPf and the reasons why the mutations yielded improved crystal structures are discussed

  18. Combinatorics of γ-Structures

    DEFF Research Database (Denmark)

    Han, Hillary Siwei; Li, Thomas Jiaxian; reidys, Christian

    2014-01-01

    In this paper we study canonical $\\gamma$-structures, a class of RNA pseudoknot structures that plays a key role in the context of polynomial time folding of RNA pseudoknot structures. A $\\gamma$-structure is composed by specific building blocks, that have topological genus less than or equal...

  19. Buckling of Ship Structures

    CERN Document Server

    Shama, Mohamed

    2013-01-01

    Buckling of Ship Structures presents a comprehensive analysis of the buckling problem of ship structural members. A full analysis of the various types of loadings and stresses imposed on ship plating and primary and secondary structural members is given. The main causes and consequences of the buckling mode of failure of ship structure and the methods commonly used to control buckling failure are clarified. This book contains the main equations required to determine the critical buckling stresses for both ship plating and the primary and secondary stiffening structural members. The critical buckling stresses are given for ship plating subjected to the induced various types of loadings and having the most common boundary conditions encountered in ship structures.  The text bridges the gap existing in most books covering the subject of buckling of ship structures in the classical analytical format, by putting the emphasis on the practical methods required to ensure safety against buckling of ship structur...

  20. Subduing the structural shakes

    International Nuclear Information System (INIS)

    Sharma, S.S.; Mercurio, E.L.; Goldenberg, E.

    1989-01-01

    The evolution of seismic design practices is related to the occurrence of major earthquakes. The amount of damage sustained by power equipment and structures during these earthquakes pointed out a necessity for the power industry to consider the dynamic behavior of equipment and structures and to reassess seismic design practices. Conventional designs typically use codes whose main intent is life safety, and whose failure criteria is structural collapse. These methods allow the entire ground motion to be transmitted to the superstructure; absorbing the seismic energy through inelastic behavior which invariably gives rise to damage, both structural and non-structural. From the standpoint of the structure's essential function, conventional designs may reduce injury to people, but the corresponding damage to the building's equipment and other non-structural components may be catastrophic. The ideal solution for this seismic design problem is to provide a system which absorbs or mitigates the seismic forces before they enter into the structural system. According to the authors, base isolation offers such an alternative

  1. Structures composing protein domains.

    Science.gov (United States)

    Kubrycht, Jaroslav; Sigler, Karel; Souček, Pavel; Hudeček, Jiří

    2013-08-01

    This review summarizes available data concerning intradomain structures (IS) such as functionally important amino acid residues, short linear motifs, conserved or disordered regions, peptide repeats, broadly occurring secondary structures or folds, etc. IS form structural features (units or elements) necessary for interactions with proteins or non-peptidic ligands, enzyme reactions and some structural properties of proteins. These features have often been related to a single structural level (e.g. primary structure) mostly requiring certain structural context of other levels (e.g. secondary structures or supersecondary folds) as follows also from some examples reported or demonstrated here. In addition, we deal with some functionally important dynamic properties of IS (e.g. flexibility and different forms of accessibility), and more special dynamic changes of IS during enzyme reactions and allosteric regulation. Selected notes concern also some experimental methods, still more necessary tools of bioinformatic processing and clinically interesting relationships. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  2. Standing wave accelerating structures

    International Nuclear Information System (INIS)

    Zavadtsev, A.A.; Zverev, B.V.; Sobepin, N.P.

    1984-01-01

    Accelerating ELA structures are considered and chosen for applied purposes of special designation. Accelerating structures with the standing wave are considered most effective for small size ELA. Designs and results of experimental investigation of two new accelerating structures are described. These are structures of the ''ring'' type with a decreased number of excitinq oscillation types and strucuture with transverse rods with a twice smaller transverse size as compared with the biperiodical structure with internal connection resonators. The accelerating biperiodical structures of the conventional type by the fact that the whole structure is not a linear chain of connected resonators, but a ring one. Model tests have shown that the homogeneous structure with transverse rods (STR) at the frequency of 2.8 GHz in the regime of the standing wave has an effective shunt resistance equalling 23 MOhm/m. It is shown that the small transverse size of biperiodic STR makes its application in logging linear electron accelerators

  3. Effects of structural nonlinearity and foundation sliding on probabilistic response of a nuclear structure

    International Nuclear Information System (INIS)

    Hashemi, Alidad; Elkhoraibi, Tarek; Ostadan, Farhang

    2015-01-01

    Highlights: • Probabilistic SSI analysis including structural nonlinearity and sliding are shown. • Analysis is done for a soil and a rock site and probabilistic demands are obtained. • Structural drift ratios and In-structure response spectra are evaluated. • Structural nonlinearity significantly impacts local demands in the structure. • Sliding generally reduces seismic demands and can be accommodated in design. - Abstract: This paper examines the effects of structural nonlinearity and foundation sliding on the results of probabilistic structural analysis of a typical nuclear structure where structural nonlinearity, foundation sliding and soil-structure interaction (SSI) are explicitly included. The evaluation is carried out for a soil and a rock site at 10"4, 10"5, and 10"6 year return periods (1E − 4, 1E − 5, and 1E − 6 hazard levels, respectively). The input motions at each considered hazard level are deaggregated into low frequency (LF) and high frequency (HF) motions and a sample size of 30 is used for uncertainty propagation. The statistical distribution of structural responses including story drifts, and in-structure response spectra (ISRS) as well as foundation sliding displacements are examined. The probabilistic implementation of explicit structural nonlinearity and foundation sliding in combination with the SSI effects are demonstrated using nonlinear response history analysis (RHA) of the structure with the foundation motions obtained from elastic SSI analyses, which are applied as input to fixed-base inelastic analyses. This approach quantifies the expected structural nonlinearity and sliding for the particular structural configuration and provides a robust analytical basis for the estimation of the probabilistic distribution of selected demands parameters both at the design level and beyond design level seismic input. For the subject structure, the inclusion of foundation sliding in the analysis is found to have reduced both

  4. Dynamic Analysis of Partially Embedded Structures Considering Soil-Structure Interaction in Time Domain

    Directory of Open Access Journals (Sweden)

    Sanaz Mahmoudpour

    2011-01-01

    Full Text Available Analysis and design of structures subjected to arbitrary dynamic loadings especially earthquakes have been studied during past decades. In practice, the effects of soil-structure interaction on the dynamic response of structures are usually neglected. In this study, the effect of soil-structure interaction on the dynamic response of structures has been examined. The substructure method using dynamic stiffness of soil is used to analyze soil-structure system. A coupled model based on finite element method and scaled boundary finite element method is applied. Finite element method is used to analyze the structure, and scaled boundary finite element method is applied in the analysis of unbounded soil region. Due to analytical solution in the radial direction, the radiation condition is satisfied exactly. The material behavior of soil and structure is assumed to be linear. The soil region is considered as a homogeneous half-space. The analysis is performed in time domain. A computer program is prepared to analyze the soil-structure system. Comparing the results with those in literature shows the exactness and competency of the proposed method.

  5. Combinatorics of γ-structures.

    Science.gov (United States)

    Han, Hillary S W; Li, Thomas J X; Reidys, Christian M

    2014-08-01

    In this article we study canonical γ-structures, a class of RNA pseudoknot structures that plays a key role in the context of polynomial time folding of RNA pseudoknot structures. A γ-structure is composed of specific building blocks that have topological genus less than or equal to γ, where composition means concatenation and nesting of such blocks. Our main result is the derivation of the generating function of γ-structures via symbolic enumeration using so called irreducible shadows. We furthermore recursively compute the generating polynomials of irreducible shadows of genus ≤ γ. The γ-structures are constructed via γ-matchings. For 1 ≤ γ ≤ 10, we compute Puiseux expansions at the unique, dominant singularities, allowing us to derive simple asymptotic formulas for the number of γ-structures.

  6. Structural simplicity as a restraint on the structure of amorphous silicon

    Science.gov (United States)

    Cliffe, Matthew J.; Bartók, Albert P.; Kerber, Rachel N.; Grey, Clare P.; Csányi, Gábor; Goodwin, Andrew L.

    2017-06-01

    Understanding the structural origins of the properties of amorphous materials remains one of the most important challenges in structural science. In this study, we demonstrate that local "structural simplicity", embodied by the degree to which atomic environments within a material are similar to each other, is a powerful concept for rationalizing the structure of amorphous silicon (a -Si) a canonical amorphous material. We show, by restraining a reverse Monte Carlo refinement against pair distribution function (PDF) data to be simpler, that the simplest model consistent with the PDF is a continuous random network (CRN). A further effect of producing a simple model of a -Si is the generation of a (pseudo)gap in the electronic density of states, suggesting that structural homogeneity drives electronic homogeneity. That this method produces models of a -Si that approach the state-of-the-art without the need for chemically specific restraints (beyond the assumption of homogeneity) suggests that simplicity-based refinement approaches may allow experiment-driven structural modeling techniques to be developed for the wide variety of amorphous semiconductors with strong local order.

  7. System Reliability of Timber Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard

    2010-01-01

    elements, alternate load path(s) etc. in the structural design. In general these characteristics can have a positive influence on system reliability of a structure however, in Eurocodes ductility is only awarded for concrete and steel structures but not for timber structures. It is well......-know that structural systems can redistribute internal forces due to ductility of a connection, i.e. some additional loads can be carried by the structure. The same effect is also possible for reinforced concrete structures and structures of steel. However, for timber structures codes do not award that ductility......For reduction of the risk of collapse in the event of loss of structural element(s), a structural engineer may take necessary steps to design a collapse-resistant structure that is insensitive to accidental circumstances e.g. by incorporating characteristics like redundancy, ties, ductility, key...

  8. Utilization of steam- and explosion-decompressed aspen wood by some anaerobes. [Acetivibrio cellulolyticus, Clostridium saccharolyticum, Zymomonas anaerobia

    Energy Technology Data Exchange (ETDEWEB)

    Khan, A W; Asther, M; Giuliano, C

    1984-01-01

    Tests made to study the suitability of using steam- and explosion-decompressed aspen wood as substrate in anaerobic fermentations indicated that after washing with dilute NaOH it becomes over 80% accessible to both mesophilic and thermophilic cellulolytic anaerobes and cellulases, compared with delignified, ball-milled pulp. After washing, this material was also found to be suitable for the single-step conversion of cellulose to ethanol using cocultures consisting of cellylolytic and ethanol-producing saccharolytic anaerobes; and without and after washing by the use of cellulolytic enzymes and ethanologenic anaerobes. 16 references, 3 tables.

  9. FUNDAMENTAL ECONOMIC STRUCTURE AND STRUCTURAL CHANGE IN REGIONAL ECONOMIES: A METHODOLOGICAL APPROACH

    OpenAIRE

    Sudhir K. THAKUR

    2011-01-01

    Regional economic structure is defined as the composition and patterns of various components of the regional economy such as: produc-tion, employment, consumption, trade, and gross regional product. Structur-al change is conceptualized as the change in relative importance of the aggregate indicators of the economy. The process of regional development and structural change are intertwined, implying as economic development takes place the strength and direction of intersectoral relationships ch...

  10. Coexistence of Cluster Structure and Mean-field-type Structure in Medium-weight Nuclei

    International Nuclear Information System (INIS)

    Taniguchi, Yasutaka; Horiuchi, Hisashi; Kimura, Masaaki

    2006-01-01

    We have studied the coexistence of cluster structure and mean-field-type structure in 20Ne and 40Ca using Antisymmetrized Molecular Dynamics (AMD) + Generator Coordinate Method (GCM). By energy variation with new constraint for clustering, we calculate cluster structure wave function. Superposing cluster structure wave functions and mean-field-type structure wave function, we found that 8Be-12C, α-36Ar and 12C-28Si cluster structure are important components of K π = 0 3 + band of 20Ne, that of normal deformed band of 40Ca and that of super deformed band of 40Ca, respectively

  11. Optoelectronic Mounting Structure

    Science.gov (United States)

    Anderson, Gene R.; Armendariz, Marcelino G.; Baca, Johnny R. F.; Bryan, Robert P.; Carson, Richard F.; Chu, Dahwey; Duckett, III, Edwin B.; McCormick, Frederick B.; Peterson, David W.; Peterson, Gary D.; Reber, Cathleen A.; Reysen, Bill H.

    2004-10-05

    An optoelectronic mounting structure is provided that may be used in conjunction with an optical transmitter, receiver or transceiver module. The mounting structure may be a flexible printed circuit board. Thermal vias or heat pipes in the head region may transmit heat from the mounting structure to the heat spreader. The heat spreader may provide mechanical rigidity or stiffness to the heat region. In another embodiment, an electrical contact and ground plane may pass along a surface of the head region so as to provide an electrical contact path to the optoelectronic devices and limit electromagnetic interference. In yet another embodiment, a window may be formed in the head region of the mounting structure so as to provide access to the heat spreader. Optoelectronic devices may be adapted to the heat spreader in such a manner that the devices are accessible through the window in the mounting structure.

  12. The overlapping community structure of structural brain network in young healthy individuals.

    Directory of Open Access Journals (Sweden)

    Kai Wu

    2011-05-01

    Full Text Available Community structure is a universal and significant feature of many complex networks in biology, society, and economics. Community structure has also been revealed in human brain structural and functional networks in previous studies. However, communities overlap and share many edges and nodes. Uncovering the overlapping community structure of complex networks remains largely unknown in human brain networks. Here, using regional gray matter volume, we investigated the structural brain network among 90 brain regions (according to a predefined anatomical atlas in 462 young, healthy individuals. Overlapped nodes between communities were defined by assuming that nodes (brain regions can belong to more than one community. We demonstrated that 90 brain regions were organized into 5 overlapping communities associated with several well-known brain systems, such as the auditory/language, visuospatial, emotion, decision-making, social, control of action, memory/learning, and visual systems. The overlapped nodes were mostly involved in an inferior-posterior pattern and were primarily related to auditory and visual perception. The overlapped nodes were mainly attributed to brain regions with higher node degrees and nodal efficiency and played a pivotal role in the flow of information through the structural brain network. Our results revealed fuzzy boundaries between communities by identifying overlapped nodes and provided new insights into the understanding of the relationship between the structure and function of the human brain. This study provides the first report of the overlapping community structure of the structural network of the human brain.

  13. Mitotic chromosome structure

    International Nuclear Information System (INIS)

    Heermann, Dieter W.

    2012-01-01

    Mounting evidence is compiling linking the physical organizational structure of chromosomes and the nuclear structure to biological function. At the base of the physical organizational structure of both is the concept of loop formation. This implies that physical proximity within chromosomes is provided for otherwise distal genomic regions and thus hierarchically organizing the chromosomes. Together with entropy many experimental observations can be explained with these two concepts. Among the observations that can be explained are the measured physical extent of the chromosomes, their shape, mechanical behavior, the segregation into territories (chromosomal and territories within chromosomes), the results from chromosome conformation capture experiments, as well as linking gene expression to structural organization.

  14. Structure guided GANs

    Science.gov (United States)

    Cao, Feidao; Zhao, Huaici; Liu, Pengfei

    2017-11-01

    Generative adversarial networks (GANs) has achieved success in many fields. However, there are some samples generated by many GAN-based works, whose structure is ambiguous. In this work, we propose Structure Guided GANs that introduce structural similar into GANs to overcome the problem. In order to achieve our goal, we introduce an encoder and a decoder into a generator to design a new generator and take real samples as part of the input of a generator. And we modify the loss function of the generator accordingly. By comparison with WGAN, experimental results show that our proposed method overcomes largely sample structure ambiguous and can generate higher quality samples.

  15. Mitotic chromosome structure

    Energy Technology Data Exchange (ETDEWEB)

    Heermann, Dieter W., E-mail: heermann@tphys.uni-heidelberg.de

    2012-07-15

    Mounting evidence is compiling linking the physical organizational structure of chromosomes and the nuclear structure to biological function. At the base of the physical organizational structure of both is the concept of loop formation. This implies that physical proximity within chromosomes is provided for otherwise distal genomic regions and thus hierarchically organizing the chromosomes. Together with entropy many experimental observations can be explained with these two concepts. Among the observations that can be explained are the measured physical extent of the chromosomes, their shape, mechanical behavior, the segregation into territories (chromosomal and territories within chromosomes), the results from chromosome conformation capture experiments, as well as linking gene expression to structural organization.

  16. The Dual Half-Arc data structure: towards the universal B-rep data structure

    DEFF Research Database (Denmark)

    Anton, François; Bugoslawski, P.; Mioc, Darka

    2014-01-01

    , or more generally, the topology of any topological space. For this purpose, we generalize an existing data structure from 2D to 3D and design a new 3D data structure that realizes the synthesis between an existing 3D data structure (the Dual Half-Edge (See Footonote 1) data structure) and the generalized...... 3D Quad-Arc data structure, (See Footonote 2) and at the same time, improves the Dual Half-Edge towards a simpler and more effective representation of cell complexes through B-rep structures. We generalize the idea of the Quad-Arc data structure from 2D to 3D, but instead of transforming a simple...... edge of the Quad-Edge data structure to an arc with multiple points along it, we group together primal edges of the Dual Half-Edge that have the same dual Half-Edge vertex tags (volume tags) into one Dual Half-Arc whose dual is the common Dual Half-Edge and primal faces corresponding to dual...

  17. Structural behavior of reinforced concrete structures at high temperatures

    International Nuclear Information System (INIS)

    Yamazaki, N.; Yamazaki, M.; Mochida, T.; Mutoh, A.; Miyashita, T.; Ueda, M.; Hasegawa, T.; Sugiyama, K.; Hirakawa, K.; Kikuchi, R.; Hiramoto, M.; Saito, K.

    1995-01-01

    To establish a method to predict the behavior of reinforced concrete structures subjected simultaneously to high temperatures and external loads, this paper presents the results obtained in several series of tests carried out recently in Japan. This paper reports on the material properties of concrete and steel bars under high temperatures. It also considers the heat transfer properties of thick concrete walls under transient high temperatures, and the structural behavior of reinforced concrete beams subjected to high temperatures. In the tests, data up to 800 C were obtained for use in developing a computational method to estimate the non-linear behavior of reinforced concrete structures exposed to high temperatures. (orig.)

  18. Compare local pocket and global protein structure models by small structure patterns

    KAUST Repository

    Cui, Xuefeng

    2015-09-09

    Researchers proposed several criteria to assess the quality of predicted protein structures because it is one of the essential tasks in the Critical Assessment of Techniques for Protein Structure Prediction (CASP) competitions. Popular criteria include root mean squared deviation (RMSD), MaxSub score, TM-score, GDT-TS and GDT-HA scores. All these criteria require calculation of rigid transformations to superimpose the the predicted protein structure to the native protein structure. Yet, how to obtain the rigid transformations is unknown or with high time complexity, and, hence, heuristic algorithms were proposed. In this work, we carefully design various small structure patterns, including the ones specifically tuned for local pockets. Such structure patterns are biologically meaningful, and address the issue of relying on a sufficient number of backbone residue fragments for existing methods. We sample the rigid transformations from these small structure patterns; and the optimal superpositions yield by these small structures are refined and reported. As a result, among 11; 669 pairs of predicted and native local protein pocket models from the CASP10 dataset, the GDT-TS scores calculated by our method are significantly higher than those calculated by LGA. Moreover, our program is computationally much more efficient. Source codes and executables are publicly available at http://www.cbrc.kaust.edu.sa/prosta/

  19. Catalytic distillation structure

    Science.gov (United States)

    Smith, L.A. Jr.

    1984-04-17

    Catalytic distillation structure is described for use in reaction distillation columns, and provides reaction sites and distillation structure consisting of a catalyst component and a resilient component intimately associated therewith. The resilient component has at least about 70 volume % open space and is present with the catalyst component in an amount such that the catalytic distillation structure consists of at least 10 volume % open space. 10 figs.

  20. Stability patterns for a size-structured population model and its stage-structured counterpart

    DEFF Research Database (Denmark)

    Zhang, Lai; Pedersen, Michael; Lin, Zhigui

    2015-01-01

    In this paper we compare a general size-structured population model, where a size-structured consumer feeds upon an unstructured resource, to its simplified stage-structured counterpart in terms of equilibrium stability. Stability of the size-structured model is understood in terms of an equivale...... to the population level....

  1. A Molecular–Structure Hypothesis

    Directory of Open Access Journals (Sweden)

    Jan C. A. Boeyens

    2010-11-01

    Full Text Available The self-similar symmetry that occurs between atomic nuclei, biological growth structures, the solar system, globular clusters and spiral galaxies suggests that a similar pattern should characterize atomic and molecular structures. This possibility is explored in terms of the current molecular structure-hypothesis and its extension into four-dimensional space-time. It is concluded that a quantum molecule only has structure in four dimensions and that classical (Newtonian structure, which occurs in three dimensions, cannot be simulated by quantum-chemical computation.

  2. PRODUCT STRUCTURE DIGITAL MODEL

    Directory of Open Access Journals (Sweden)

    V.M. Sineglazov

    2005-02-01

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

  3. Decoupling structure and metallogenesis

    International Nuclear Information System (INIS)

    Tong Hangshou

    1993-01-01

    The decoupling structure is, at present, a hot spot for the study in geoscience. A study on the decoupling structure is not only of great theoretical significance, but also of more economic importance. The author briefly discusses the study of the decoupling structure in terms of its present status, implication, characteristics, formation mechanism and theoretical significance, in addition, with emphasis on the expounding of the decoupling structure over endogenic metallic deposits such as oil and gas, coal, gold, silver, copper, lead, zinc and iron etc. At last reconsideration is made on the ore control theory of the decoupling structure to the ore control structure in the uranium ore field in South China. The author proposes a superficial idea in order to provide a basis of geological structures for expanding old mining areas, opening up new areas(bases), and prospecting for large and rich uranium deposits

  4. Quality assessment of protein model-structures based on structural and functional similarities.

    Science.gov (United States)

    Konopka, Bogumil M; Nebel, Jean-Christophe; Kotulska, Malgorzata

    2012-09-21

    Experimental determination of protein 3D structures is expensive, time consuming and sometimes impossible. A gap between number of protein structures deposited in the World Wide Protein Data Bank and the number of sequenced proteins constantly broadens. Computational modeling is deemed to be one of the ways to deal with the problem. Although protein 3D structure prediction is a difficult task, many tools are available. These tools can model it from a sequence or partial structural information, e.g. contact maps. Consequently, biologists have the ability to generate automatically a putative 3D structure model of any protein. However, the main issue becomes evaluation of the model quality, which is one of the most important challenges of structural biology. GOBA--Gene Ontology-Based Assessment is a novel Protein Model Quality Assessment Program. It estimates the compatibility between a model-structure and its expected function. GOBA is based on the assumption that a high quality model is expected to be structurally similar to proteins functionally similar to the prediction target. Whereas DALI is used to measure structure similarity, protein functional similarity is quantified using standardized and hierarchical description of proteins provided by Gene Ontology combined with Wang's algorithm for calculating semantic similarity. Two approaches are proposed to express the quality of protein model-structures. One is a single model quality assessment method, the other is its modification, which provides a relative measure of model quality. Exhaustive evaluation is performed on data sets of model-structures submitted to the CASP8 and CASP9 contests. The validation shows that the method is able to discriminate between good and bad model-structures. The best of tested GOBA scores achieved 0.74 and 0.8 as a mean Pearson correlation to the observed quality of models in our CASP8 and CASP9-based validation sets. GOBA also obtained the best result for two targets of CASP8, and

  5. Structural Evaluation of the Second Oldest Glued-Laminated Structure in the United States

    Science.gov (United States)

    Douglas R. Rammer; Jorge de Melo Moura

    2013-01-01

    The second glued-laminated structure built in the United States was constructed at the USDA Forest Products Laboratory (FPL) in 1934 to demonstrate the performance of wooden arch buildings. After decades of use the structure was decommissioned in 2010. Shortly after construction, researchers structurally evaluated the glued-laminated arch structure for uniform loading...

  6. Reforming Organizational Structures

    OpenAIRE

    Van de Walle, Steven

    2016-01-01

    textabstractPublic sectors have undergone major transformations. Public sector reform touches upon the core building blocks of the public sector: organizational structures, people and finances. These are objects of reform. This chapter presents and discusses a set of major transformations with regard to organizational structures. It provides readers a fairly comprehensive overview of the key reforms that have taken place in Western public sectors. Structural reforms in the public sector show ...

  7. BOMB STABILIZING STRUCTURE

    Science.gov (United States)

    Kelley, J.L.; Runyan, C.E.

    1963-12-10

    A stabilizinig structure capable of minimizing deviations of a falling body such as a bomb from desired trajectory is described. The structure comprises a fin or shroud arrangement of double-wedge configuration, the feeding portion being of narrow wedge shape and the after portion being of a wider wedge shape. The structure provides a force component for keeping the body on essentially desired trajectory throughout its fall. (AEC)

  8. A density functional study of backbone structures of polydiacetylene: destabilization of butatriene structure

    International Nuclear Information System (INIS)

    Katagiri, Hideki; Shimoi, Yukihiro; Abe, Shuji

    2004-01-01

    Backbone structures of polydiacetylene are studied with first-principles electronic structure method using plane-waves within generalized gradient approximation (GGA) of density functional theory. In spin-restricted calculations a coarse k-point sampling gives a potential energy curve with two local minima corresponding to acetylene and butatriene structures. However, the potential barrier between the two structures rapidly decreases with increasing number of k-points, which results in destabilization of the butatriene structure. Spin polarization effects also destabilize the butatriene structure, inducing atom-centered spin-density-wave state. These potential energies were compared with those obtained by Hartree-Fock, density functional within local density approximation (LDA) and GGA, and hybrid density functional methods using a gaussian basis set. The comparison shows that the density functional methods within LDA and GGA favor the destabilization of the butatriene structure in contrast to the Hartree-Fock method

  9. Submicron superconducting structures

    International Nuclear Information System (INIS)

    Golovashkin, A.I.; Lykov, A.N.

    1986-01-01

    An overview of works concerning superconducting structures of submicron dimensions and a system of such structures is given. It is noted that usage of the above structures in superconducting microelectronics permits, first, to increase the element packing density, to decrease the signal transmission time, capacity, power dissipated in high-frequency applications. Secondly, negligible coherence length in transition metals, their alloys and high-temperature compounds also restrict the dimensions of superconducting weak couplings when the 'classical' Josephson effect is displayed. The most effective methods for production of submicron superconducting structures are the following: lithography, double scribering. Recently the systems of superconducting submicron elements are extensively studied. It is shown that such systems can be phased by magnetic field

  10. STRUCTURAL SCALE LIFE PREDICTION OF AERO STRUCTURES EXPERIENCING COMBINED EXTREME ENVIRONMENTS

    Science.gov (United States)

    2017-07-01

    complex loading environments. Today’s state of the art methods cannot address structural reliability under combined environment conditions due to...probabilistically assess the structural life under complex loading environments. Today’s state of the art methods cannot address structural reliability...Institute of Aeronautics and Astronautics, San Diego, CA, January 4th‐8th, 2016. Clark, L. D., Bae, H., Gobal, K., and Penmetsa, R., “ Engineering

  11. Structural Performance of the Second Oldest Glued-Laminated Structure in the United States

    Science.gov (United States)

    Douglas R. Rammer; Jorge de Melo Moura; Robert J. Ross

    2014-01-01

    The second glued-laminated structure built in the United States was constructed at the USDA Forest Products Laboratory (FPL) in 1934 to demonstrate the performance of wooden arch buildings. After 75 years of use the structure was decommissioned in 2010. Shortly after construction, researchers structurally evaluated the glued-laminated arch structure for uniform loading...

  12. Implications of social structure

    DEFF Research Database (Denmark)

    Brask, Josefine Bohr

    Social systems in nature are characterised by heterogeneous social structures. The pattern of social interactions or associations between individuals within populations (i.e. their social network) is typically non-random. Such structuring may have important implications for the expression...... and evolution of behaviour, and for individual fitness. In this thesis I investigated implications of social structure for fitness and behaviour, with focus on three main areas: social structure & fitness, social structure & communication, and social structure & cooperation. These areas were investigated......, we investigate empirically the role of the social environment of individuals for their communication patterns. Our study species is a song bird, the black-capped chickadee (Poecile atricapillus). The results suggest that individual communication in this species is influenced by features of the local...

  13. Optimal reinforcing of reticular structures Optimal reinforcing of reticular structures

    Directory of Open Access Journals (Sweden)

    Juan Santiago Mejía

    2006-12-01

    Full Text Available This article presents an application of Genetic Algorithms (GA and Finite Element Analysis (FEA to solve a structural optimisation problem on reticular plastic structures. Structural optimisation is used to modify the original shape by placing reinforcements at optimum locations. As a result, a reduction in the maximum stress by 14,70% for a structure with a final volume increase of 8,36% was achieved. This procedure solves the structural optimisation problem by adjusting the original mold and thereby avoiding the re-construction of a new one.Este artículo presenta una aplicación de Algoritmos Genéticos (GA y Análisis por Elementos Finitos (FEA a la solución de un problema de optimización estructural en estructuras reticulares plásticas. Optimización estructurales usada para modificar la forma original colocando refuerzos en posiciones óptimas. Como resultado se obtuvo una reducción en el esfuerzo máximo de 14,70% para una estructura cuyo volumen original aumento en 8,36%. Este procedimiento soluciona el problema de optimización estructural ajustando el molde original y evitando la manufactura de un nuevo molde.

  14. Photothermal modification of plasmonic structures

    DEFF Research Database (Denmark)

    2016-01-01

    There is presented a method for geometrically modifying plasmonic structures on a support structure, such as for printing or recording, said method comprising changing a geometry specifically of plasmonic structures, wherein said changing the geometry is carried out by photothermally melting...... at least a portion of each of the plasmonic structures within the second plurality of plasmonic structures by irradiating, the plasmonic structures with incident electromagnetic radiation having an incident intensity in a plane of the second plurality of plasmonic structures, wherein said incident...... intensity is less than an incident intensity required to melt a film of a corresponding material and a corresponding thickness as the plasmonic structures within the second plurality of plasmonic structures....

  15. SOIL STRUCTURE INTERACTION EFFECTS ON MULTISTOREY R/C STRUCTURES

    Directory of Open Access Journals (Sweden)

    Muberra ESER AYDEMIR

    2013-01-01

    Full Text Available This paper addresses the behavior of multistorey structures considering soil structure interaction under earthquake excitation. For this purpose, sample 3, 6, 9 storey RC frames are designed based on Turkish Seismic Design Code and analyzed in time domain with incremental dynamic analysis. Strength reduction factors are investigated for generated sample plane frames for 64 different earthquake motions recorded on different site conditions such as rock, stiff soil, soft soil and very soft soil. According to the analysis result, strength reduction factors of sample buildings considering soil structure interaction are found to be almost always smaller than design strength reduction factors given in current seismic design codes, which cause an unsafe design and nonconservative design forces.

  16. Atomic and electronic structures of novel silicon surface structures

    Energy Technology Data Exchange (ETDEWEB)

    Terry, J.H. Jr.

    1997-03-01

    The modification of silicon surfaces is presently of great interest to the semiconductor device community. Three distinct areas are the subject of inquiry: first, modification of the silicon electronic structure; second, passivation of the silicon surface; and third, functionalization of the silicon surface. It is believed that surface modification of these types will lead to useful electronic devices by pairing these modified surfaces with traditional silicon device technology. Therefore, silicon wafers with modified electronic structure (light-emitting porous silicon), passivated surfaces (H-Si(111), Cl-Si(111), Alkyl-Si(111)), and functionalized surfaces (Alkyl-Si(111)) have been studied in order to determine the fundamental properties of surface geometry and electronic structure using synchrotron radiation-based techniques.

  17. Robustness Analyses of Timber Structures

    DEFF Research Database (Denmark)

    Kirkegaard, Poul Henning; Sørensen, John Dalsgaard; Hald, Frederik

    2013-01-01

    The robustness of structural systems has obtained a renewed interest arising from a much more frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure. In order to minimise the likelihood of such disproportionate structural failures, many mo...... with respect to robustness of timber structures and will discuss the consequences of such robustness issues related to the future development of timber structures.......The robustness of structural systems has obtained a renewed interest arising from a much more frequent use of advanced types of structures with limited redundancy and serious consequences in case of failure. In order to minimise the likelihood of such disproportionate structural failures, many...... modern building codes consider the need for the robustness of structures and provide strategies and methods to obtain robustness. Therefore, a structural engineer may take necessary steps to design robust structures that are insensitive to accidental circumstances. The present paper summaries issues...

  18. The relationship between energy consumption structure, economic structure and energy intensity in China

    International Nuclear Information System (INIS)

    Feng Taiwen; Sun Linyan; Zhang Ying

    2009-01-01

    This paper investigates the long-run equilibrium relationships, temporal dynamic relationships and causal relationships between energy consumption structure, economic structure and energy intensity in China. Time series variables over the periods from 1980 to 2006 are employed in empirical tests. Cointegration tests suggest that these three variables tend to move together in the long-run. In addition, Granger causality tests indicate that there is a unidirectional causality running from energy intensity to economic structure but not vice versa. Impulse response analysis provides reasonable evidences that one shock of the three variables will cause the periods of destabilized that followed. However, the impact of the energy consumption structure shock on energy intensity and the impact of the economic structure shock on energy consumption structure seem to be rather marginal. The findings have significant implications from the point of view of energy conservation and economic development. In order to decrease energy intensity, Chinese government must continue to reduce the proportion of coal in energy consumption, increase the utilization efficiency of coal and promote the upgrade of economic structure. Furthermore, a full analysis of factors that may relate to energy intensity (e.g. energy consumption structure, economic structure) should be conducted before making energy policies.

  19. Numerical procedure for fluid-structure interaction with structure displacements limited by a rigid obstacle

    Directory of Open Access Journals (Sweden)

    Yakhlef O.

    2017-06-01

    Full Text Available A fixed point algorithmis proposed to solve a fluid-structure interaction problem with the supplementary constraint that the structure displacements are limited by a rigid obstacle. Fictitious domain approach with penalization is used for the fluid equations. The surface forces from the fluid acting on the structure are computed using the fluid solution in the structure domain. The continuity of the fluid and structure velocities is imposed through the penalization parameter. The constraint of non-penetration of the elastic structure into the rigid obstacle is treated weakly. A convex constrained optimization problem is solved in order to get the structure displacements. Numerical results are presented.

  20. Virtual sensors for active noise control in acoustic-structural coupled enclosures using structural sensing: part II--Optimization of structural sensor placement.

    Science.gov (United States)

    Halim, Dunant; Cheng, Li; Su, Zhongqing

    2011-04-01

    The work proposed an optimization approach for structural sensor placement to improve the performance of vibro-acoustic virtual sensor for active noise control applications. The vibro-acoustic virtual sensor was designed to estimate the interior sound pressure of an acoustic-structural coupled enclosure using structural sensors. A spectral-spatial performance metric was proposed, which was used to quantify the averaged structural sensor output energy of a vibro-acoustic system excited by a spatially varying point source. It was shown that (i) the overall virtual sensing error energy was contributed additively by the modal virtual sensing error and the measurement noise energy; (ii) each of the modal virtual sensing error system was contributed by both the modal observability levels for the structural sensing and the target acoustic virtual sensing; and further (iii) the strength of each modal observability level was influenced by the modal coupling and resonance frequencies of the associated uncoupled structural/cavity modes. An optimal design of structural sensor placement was proposed to achieve sufficiently high modal observability levels for certain important panel- and cavity-controlled modes. Numerical analysis on a panel-cavity system demonstrated the importance of structural sensor placement on virtual sensing and active noise control performance, particularly for cavity-controlled modes.

  1. [Hospital organizational structure].

    Science.gov (United States)

    Bittar, O J

    1994-01-01

    The basic point for an Institution to work is the existence of a definite organizational structure that puts together similar areas allowing decisions and the operationalization of different tasks. Knowledge and analysis of structures of private and public hospitals and a bibliography review about the issue is the purpose of this paper. Suggestions are given about the elaboration of small structures and the utilization of matrix management in order to accomplish the hospitals objectives.

  2. Structural stability, electronic structure and mechanical properties of actinide carbides AnC (An = U, Np)

    International Nuclear Information System (INIS)

    Manikandan, M.; Santhosh, M.; Rajeswarapalanichamy, R.

    2016-01-01

    Ab initio calculations are performed to investigate the structural stability, electronic structure and mechanical properties of actinide carbides AnC (An=U, Np) for three different crystal structures, namely NaCl, CsCl and ZnS. Among the considered structures, NaCl structure is found to be the most stable structure for these carbides at normal pressure. A pressure induced structural phase transition from NaCl to ZnS is observed. The electronic structure reveals that these carbides are metals. The calculated elastic constants indicate that these carbides are mechanically stable at normal pressure.

  3. Exploiting structure similarity in refinement: automated NCS and target-structure restraints in BUSTER

    Energy Technology Data Exchange (ETDEWEB)

    Smart, Oliver S., E-mail: osmart@globalphasing.com; Womack, Thomas O.; Flensburg, Claus; Keller, Peter; Paciorek, Włodek; Sharff, Andrew; Vonrhein, Clemens; Bricogne, Gérard [Global Phasing Ltd, Sheraton House, Castle Park, Cambridge CB3 0AX (United Kingdom)

    2012-04-01

    Local structural similarity restraints (LSSR) provide a novel method for exploiting NCS or structural similarity to an external target structure. Two examples are given where BUSTER re-refinement of PDB entries with LSSR produces marked improvements, enabling further structural features to be modelled. Maximum-likelihood X-ray macromolecular structure refinement in BUSTER has been extended with restraints facilitating the exploitation of structural similarity. The similarity can be between two or more chains within the structure being refined, thus favouring NCS, or to a distinct ‘target’ structure that remains fixed during refinement. The local structural similarity restraints (LSSR) approach considers all distances less than 5.5 Å between pairs of atoms in the chain to be restrained. For each, the difference from the distance between the corresponding atoms in the related chain is found. LSSR applies a restraint penalty on each difference. A functional form that reaches a plateau for large differences is used to avoid the restraints distorting parts of the structure that are not similar. Because LSSR are local, there is no need to separate out domains. Some restraint pruning is still necessary, but this has been automated. LSSR have been available to academic users of BUSTER since 2009 with the easy-to-use -autoncs and @@target target.pdb options. The use of LSSR is illustrated in the re-refinement of PDB entries http://scripts.iucr.org/cgi-bin/cr.cgi?rm, where -target enables the correct ligand-binding structure to be found, and http://scripts.iucr.org/cgi-bin/cr.cgi?rm, where -autoncs contributes to the location of an additional copy of the cyclic peptide ligand.

  4. Smart Sensing Technologies for Structural Health Monitoring of Civil Engineering Structures

    OpenAIRE

    M. Sun; W. J. Staszewski; R. N. Swamy

    2010-01-01

    Structural Health Monitoring (SHM) aims to develop automated systems for the continuous monitoring, inspection, and damage detection of structures with minimum labour involvement. The first step to set up a SHM system is to incorporate a level of structural sensing capability that is reliable and possesses long term stability. Smart sensing technologies including the applications of fibre optic sensors, piezoelectric sensors, magnetostrictive sensors and self-diagnosing fibre reinforced compo...

  5. Cross-cultural structures of concentric and diametric dualism in Lévi-Strauss' structural anthropology: structures of relation underlying the self and ego relation?

    Science.gov (United States)

    Downes, Paul

    2003-02-01

    The parallels between Jung's and Lévi-Strauss' concentric cross-cultural structures of the unconscious are highlighted. Lévi-Strauss' basic contrasts between concentric and diametric dualisms are developed into psychologically relevant differences regarding symmetry, connection and separation, and interaction between foreground and background structures respectively. These contrasts between concentric and diametric structures are applied as a common structural framework for understanding Jungian conceptions of the self, the ego and their relations, Freudian views of compensation and repetition in obsessional neurosis, and Winnicott's conception of a child's transitional object. Developing the contrasts between concentric and diametric structures reveals a compensatory relation between both structures. This supports an argument that concentric structures express the self and diametric structures express the ego in their mutual compensatory interrelation. Contrasting concentric with diametric structures challenges traditional Western logic, including Fordham's view that it is contradictory to treat the self as both centre and totality. It also develops an understanding of Jung's transcendent function which seeks to go beyond the ego-shadow opposition.

  6. Neighborhood structure effects on the Dynamic response of soil-structure interaction by harmonic analysis

    Directory of Open Access Journals (Sweden)

    Pan Dan-guang

    2015-01-01

    Full Text Available For realizing the variation of structural dynamic characteristics due to neighbor structure in buildings group, the surface structure is idealized as an equivalent single degree of freedom system with rigid base whose site consists of a single homogeneous layer. Based on the model, a equivalent method on the equivalent seismic excitation is proposed. Then, the differences of seismic response and equivalent seismic input between soil - structure interaction (SSI system and structure -soil-structure interaction (SSSI system are investigated by harmonic analysis. The numerical results show that dynamic responses would be underestimated in SSSI system when the forcing frequencies are close to the Natural frequency if the effects of neighborhood structure were ignored. Neighborhood structure would make the translational displacement increase and rocking vibration decrease. When establishing an effective seismic input, it is necessary to consider the impact of inertia interaction.

  7. Structural Dynamics

    DEFF Research Database (Denmark)

    Nielsen, Søren R.K.

    The present textbook has been written for a course on stochastic vibration theory that is being given on the 9th semester at Aalborg University for M.Sc. students in structural engineering.......The present textbook has been written for a course on stochastic vibration theory that is being given on the 9th semester at Aalborg University for M.Sc. students in structural engineering....

  8. Structural property of platinum mononitride

    International Nuclear Information System (INIS)

    Yu, L.H.; Yao, K.L.; Liu, Z.L.; Zhang, Y.S.

    2007-01-01

    The structural stability and pressure-induced structural phase transition of platinum mononitride (PtN), as well as its electronic structure, were studied using the full potential augmented plane wave plus local orbitals method with the generalized gradient approximation (GGA) exchange-correlation functional. The total energy calculations show that the optimized wurtzite structure is most stable energetically among four structures: zinc blende, rocksalt, CsCl and wurtzite, which reveals the platinum mononitride PtN perhaps crystallizes in the wurtzite structure; the pressure of phase transition from wurtzite to rocksalt is predicted to be 41.4 GPa.The calculated bulk modulus of the wurtzite structure is 99.41 GPa, which is smaller than that of the other three structures and face-centered cubic Pt. The band structure calculations show wurtzite PtN is metallic

  9. WEB STRUCTURE MINING

    Directory of Open Access Journals (Sweden)

    CLAUDIA ELENA DINUCĂ

    2011-01-01

    Full Text Available The World Wide Web became one of the most valuable resources for information retrievals and knowledge discoveries due to the permanent increasing of the amount of data available online. Taking into consideration the web dimension, the users get easily lost in the web’s rich hyper structure. Application of data mining methods is the right solution for knowledge discovery on the Web. The knowledge extracted from the Web can be used to raise the performances for Web information retrievals, question answering and Web based data warehousing. In this paper, I provide an introduction of Web mining categories and I focus on one of these categories: the Web structure mining. Web structure mining, one of three categories of web mining for data, is a tool used to identify the relationship between Web pages linked by information or direct link connection. It offers information about how different pages are linked together to form this huge web. Web Structure Mining finds hidden basic structures and uses hyperlinks for more web applications such as web search.

  10. Selected topics in nuclear structure

    Energy Technology Data Exchange (ETDEWEB)

    Solov` ev, V G; Gromov, K Ya; Malov, L A; Shilov, V M

    1994-12-31

    The Fourth International Conference on selected topics in nuclear structure was held at Dubna in July 1994 on recent experimental and theoretical investigations in nuclear structure. Topics discussed were the following: nuclear structure at low-energy excitations (collective quasiparticle phenomena, proton-neutron interactions, microscopic and phenomenological theories of nuclear structure; nuclear structure studies with charged particles). heavy ions, neutrons and photons; nuclei at high angular momenta and superdeformation, structure and decay properties of giant resonances, charge-exchange resonances and {beta}-decay; semiclassical approach of large amplitude collective motion and structure of hot nuclei.

  11. Analytical estimates of structural behavior

    CERN Document Server

    Dym, Clive L

    2012-01-01

    Explicitly reintroducing the idea of modeling to the analysis of structures, Analytical Estimates of Structural Behavior presents an integrated approach to modeling and estimating the behavior of structures. With the increasing reliance on computer-based approaches in structural analysis, it is becoming even more important for structural engineers to recognize that they are dealing with models of structures, not with the actual structures. As tempting as it is to run innumerable simulations, closed-form estimates can be effectively used to guide and check numerical results, and to confirm phys

  12. Selected topics in nuclear structure

    International Nuclear Information System (INIS)

    Solov'ev, V.G.; Gromov, K.Ya.; Malov, L.A.; Shilov, V.M.

    1994-01-01

    The Fourth International Conference on selected topics in nuclear structure was held at Dubna in July 1994 on recent experimental and theoretical investigations in nuclear structure. Topics discussed were the following: nuclear structure at low-energy excitations (collective quasiparticle phenomena, proton-neutron interactions, microscopic and phenomenological theories of nuclear structure; nuclear structure studies with charged particles. heavy ions, neutrons and photons; nuclei at high angular momenta and superdeformation, structure and decay properties of giant resonances, charge-exchange resonances and β-decay; semiclassical approach of large amplitude collective motion and structure of hot nuclei

  13. Development of the tube bundle structure for fluid-structure interaction analysis model - Intermediate Report -

    International Nuclear Information System (INIS)

    Yoon, Kyung Ho; Kim, Jae Yong; Lee, Kang Hee; Lee, Young Ho; Kim, Hyung Kyu

    2009-07-01

    Tube bundle structures within a Boiler or heat exchanger are laid the fluid-structure, thermal-structure and fluid-thermal-structure coupled boundary condition. In these complicated boundary conditions, Fluid-structure interaction (FSI) occurs when fluid flow causes deformation of the structure. This deformation, in turn, changes the boundary conditions for the fluid flow. The structural analysis have been executed as follows. First of all, divide the fluid and structural analysis discipline, and then independently analyzed each other. However, the fluid dynamic force effect the behavior of the structure, and the vibration amplitude of the structure to fluid. FSI analysis model was separately created fluid and structure model, and then defined the fsi boundary condition, and simultaneously analyzed in one domain. The analysis results were compared with those of the experimental method for validating the analysis model. Flow-induced vibration test was executed with single rod configuration. The vibration amplitudes of a fuel rod were measured by the laser vibro-meter system in x and y-direction. The analyses results were not closely with the test data, but the trend was very similar with the test result. In fsi coupled analysis case, the turbulent model was very important with the reliability of the accuracy of the analysis model. Therefore, the analysis model will be needed to further study

  14. Functional Coverage of the Human Genome by Existing Structures, Structural Genomics Targets, and Homology Models.

    Directory of Open Access Journals (Sweden)

    2005-08-01

    Full Text Available The bias in protein structure and function space resulting from experimental limitations and targeting of particular functional classes of proteins by structural biologists has long been recognized, but never continuously quantified. Using the Enzyme Commission and the Gene Ontology classifications as a reference frame, and integrating structure data from the Protein Data Bank (PDB, target sequences from the structural genomics projects, structure homology derived from the SUPERFAMILY database, and genome annotations from Ensembl and NCBI, we provide a quantified view, both at the domain and whole-protein levels, of the current and projected coverage of protein structure and function space relative to the human genome. Protein structures currently provide at least one domain that covers 37% of the functional classes identified in the genome; whole structure coverage exists for 25% of the genome. If all the structural genomics targets were solved (twice the current number of structures in the PDB, it is estimated that structures of one domain would cover 69% of the functional classes identified and complete structure coverage would be 44%. Homology models from existing experimental structures extend the 37% coverage to 56% of the genome as single domains and 25% to 31% for complete structures. Coverage from homology models is not evenly distributed by protein family, reflecting differing degrees of sequence and structure divergence within families. While these data provide coverage, conversely, they also systematically highlight functional classes of proteins for which structures should be determined. Current key functional families without structure representation are highlighted here; updated information on the "most wanted list" that should be solved is available on a weekly basis from http://function.rcsb.org:8080/pdb/function_distribution/index.html.

  15. Structural dynamics in FBR

    International Nuclear Information System (INIS)

    Bhoje, S.B.

    2003-01-01

    In view of thin walled large diameter shell structures with associated fluid effects, structural dynamics problems are very critical in a fast breeder reactor. Structural characteristics and consequent structural dynamics problems in typical pool type Fast Breeder Reactor are highlighted. A few important structural dynamics problems are pump induced as well as flow induced vibrations, seismic excitations, pressure transients in the intermediate heat exchangers and pipings due to a large sodium water reaction in the steam generator, and core disruptive accident loadings. The vibration problems which call for identification of excitation forces, formulation of special governing equations and detailed analysis with fluid structure interaction and sloshing effects, particularly for the components such as PSP, inner vessel, CP, CSRDM and TB are elaborated. Seismic design issues are presented in a comprehensive way. Other transient loadings which are specific to FBR, resulting from sodium-water reaction and core disruptive accident are highlighted. A few important results of theoretical as well as experimental works carried out for 500 MWe Prototype Fast Breeder Reactor (PFBR), in the domain of structural dynamics are presented. (author)

  16. NMR structure of the protein NP-247299.1: comparison with the crystal structure

    International Nuclear Information System (INIS)

    Jaudzems, Kristaps; Geralt, Michael; Serrano, Pedro; Mohanty, Biswaranjan; Horst, Reto; Pedrini, Bill; Elsliger, Marc-André; Wilson, Ian A.; Wüthrich, Kurt

    2010-01-01

    Comparison of the NMR and crystal structures of a protein determined using largely automated methods has enabled the interpretation of local differences in the highly similar structures. These differences are found in segments of higher B values in the crystal and correlate with dynamic processes on the NMR chemical shift timescale observed in solution. The NMR structure of the protein NP-247299.1 in solution at 313 K has been determined and is compared with the X-ray crystal structure, which was also solved in the Joint Center for Structural Genomics (JCSG) at 100 K and at 1.7 Å resolution. Both structures were obtained using the current largely automated crystallographic and solution NMR methods used by the JCSG. This paper assesses the accuracy and precision of the results from these recently established automated approaches, aiming for quantitative statements about the location of structure variations that may arise from either one of the methods used or from the different environments in solution and in the crystal. To evaluate the possible impact of the different software used for the crystallographic and the NMR structure determinations and analysis, the concept is introduced of reference structures, which are computed using the NMR software with input of upper-limit distance constraints derived from the molecular models representing the results of the two structure determinations. The use of this new approach is explored to quantify global differences that arise from the different methods of structure determination and analysis versus those that represent interesting local variations or dynamics. The near-identity of the protein core in the NMR and crystal structures thus provided a basis for the identification of complementary information from the two different methods. It was thus observed that locally increased crystallographic B values correlate with dynamic structural polymorphisms in solution, including that the solution state of the protein involves

  17. Structural Measures - Hospital

    Data.gov (United States)

    U.S. Department of Health & Human Services — A list of hospitals and the structural measures they report. A structural measure reflects the environment in which hospitals care for patients, for example, whether...

  18. Semiconductor wire array structures, and solar cells and photodetectors based on such structures

    Science.gov (United States)

    Kelzenberg, Michael D.; Atwater, Harry A.; Briggs, Ryan M.; Boettcher, Shannon W.; Lewis, Nathan S.; Petykiewicz, Jan A.

    2014-08-19

    A structure comprising an array of semiconductor structures, an infill material between the semiconductor materials, and one or more light-trapping elements is described. Photoconverters and photoelectrochemical devices based on such structure also described.

  19. High spin structure functions

    International Nuclear Information System (INIS)

    Khan, H.

    1990-01-01

    This thesis explores deep inelastic scattering of a lepton beam from a polarized nuclear target with spin J=1. After reviewing the formation for spin-1/2, the structure functions for a spin-1 target are defined in terms of the helicity amplitudes for forward compton scattering. A version of the convolution model, which incorporates relativistic and binding energy corrections is used to calculate the structure functions of a neutron target. A simple parameterization of these structure functions is given in terms of a few neutron wave function parameters and the free nucleon structure functions. This allows for an easy comparison of structure functions calculated using different neutron models. (author)

  20. An expert system for integrated structural analysis and design optimization for aerospace structures

    Science.gov (United States)

    1992-04-01

    The results of a research study on the development of an expert system for integrated structural analysis and design optimization is presented. An Object Representation Language (ORL) was developed first in conjunction with a rule-based system. This ORL/AI shell was then used to develop expert systems to provide assistance with a variety of structural analysis and design optimization tasks, in conjunction with procedural modules for finite element structural analysis and design optimization. The main goal of the research study was to provide expertise, judgment, and reasoning capabilities in the aerospace structural design process. This will allow engineers performing structural analysis and design, even without extensive experience in the field, to develop error-free, efficient and reliable structural designs very rapidly and cost-effectively. This would not only improve the productivity of design engineers and analysts, but also significantly reduce time to completion of structural design. An extensive literature survey in the field of structural analysis, design optimization, artificial intelligence, and database management systems and their application to the structural design process was first performed. A feasibility study was then performed, and the architecture and the conceptual design for the integrated 'intelligent' structural analysis and design optimization software was then developed. An Object Representation Language (ORL), in conjunction with a rule-based system, was then developed using C++. Such an approach would improve the expressiveness for knowledge representation (especially for structural analysis and design applications), provide ability to build very large and practical expert systems, and provide an efficient way for storing knowledge. Functional specifications for the expert systems were then developed. The ORL/AI shell was then used to develop a variety of modules of expert systems for a variety of modeling, finite element analysis, and

  1. Structure sensitivity in adsorption

    DEFF Research Database (Denmark)

    Hammer, Bjørk; Nielsen, Ole Holm; Nørskov, Jens Kehlet

    1997-01-01

    The structure sensitivity of CO adsorption on different flat, stepped, kinked and reconstructed Pt surfaces is studied using large-scale density-functional calculations. We find an extremely strong structure sensitivity in the adsorption energy with variations up to 1 eV (or 100%) from one...... structure to the next. We propose a model to explain this behavior, and use it to discuss more generally the origin of structure sensitivity in heterogeneous catalysis....

  2. Evolution of structure with Fe layer thickness in low dimensional Fe/Tb multilayered structures

    International Nuclear Information System (INIS)

    Harris, V.G.; Aylesworth, K.D.; Elam, W.T.; Koon, N.C.; Coehoorn, R.; Hoving, W.

    1992-01-01

    This paper reports on the atomic structure of a series of low-dimensional Fe/Tb multilayered structures which has been explored using a conversion-electron, extended x-ray absorption fine structure (EXAFS) technique. A structural transition from a close-packed amorphous structure to a body-centered crystalline structure is detected to occur over an Fe layer thickness range of 12.5 Angstrom to 15.0 Angstrom (Tb thickness is held constant at 4.5 Angstrom). Magnetic properties, specifically, magnetization, anisotropy field, and Kerr rotation angle, are measured and found to change significantly in response to this transition. Exploitation of the polarization properties of synchrotron radiation allowed for the description of the atomic structure both perpendicular and parallel to the sample plane

  3. Weakly nonlocal symplectic structures, Whitham method and weakly nonlocal symplectic structures of hydrodynamic type

    International Nuclear Information System (INIS)

    Maltsev, A Ya

    2005-01-01

    We consider the special type of field-theoretical symplectic structures called weakly nonlocal. The structures of this type are, in particular, very common for integrable systems such as KdV or NLS. We introduce here the special class of weakly nonlocal symplectic structures which we call weakly nonlocal symplectic structures of hydrodynamic type. We investigate then the connection of such structures with the Whitham averaging method and propose the procedure of 'averaging' the weakly nonlocal symplectic structures. The averaging procedure gives the weakly nonlocal symplectic structure of hydrodynamic type for the corresponding Whitham system. The procedure also gives 'action variables' corresponding to the wave numbers of m-phase solutions of the initial system which give the additional conservation laws for the Whitham system

  4. Hadron structure functions

    International Nuclear Information System (INIS)

    Martin, F.

    1981-03-01

    The x dependence of hadron structure functions is investigated. If quarks can exist in very low mass states (10 MeV for d and u quarks) the pion structure function is predicted to behave like (1-x) and not (1-x) 2 in a x-region around 1. Relativistic and non-relativistic quark bound state pictures of hadrons are considered together with their relation with the Q 2 evolution of structure functions. Good agreement with data is in general obtained

  5. Photon structure function

    International Nuclear Information System (INIS)

    Bardeen, W.A.

    1980-11-01

    Theoretical understanding of the photon structure function is reviewed. As an illustration of the pointlike component, the parton model is briefly discussed. However, the systematic study of the photon structure function is presented through the framework of the operator product expansion. Perturbative QCD is used as the theoretical basis for the calculation of leading contributions to the operator product expansion. The influence of higher order QCD effects on these results is discussed. Recent results for the polarized structure functions are discussed

  6. [Network structures in biological systems].

    Science.gov (United States)

    Oleskin, A V

    2013-01-01

    Network structures (networks) that have been extensively studied in the humanities are characterized by cohesion, a lack of a central control unit, and predominantly fractal properties. They are contrasted with structures that contain a single centre (hierarchies) as well as with those whose elements predominantly compete with one another (market-type structures). As far as biological systems are concerned, their network structures can be subdivided into a number of types involving different organizational mechanisms. Network organization is characteristic of various structural levels of biological systems ranging from single cells to integrated societies. These networks can be classified into two main subgroups: (i) flat (leaderless) network structures typical of systems that are composed of uniform elements and represent modular organisms or at least possess manifest integral properties and (ii) three-dimensional, partly hierarchical structures characterized by significant individual and/or intergroup (intercaste) differences between their elements. All network structures include an element that performs structural, protective, and communication-promoting functions. By analogy to cell structures, this element is denoted as the matrix of a network structure. The matrix includes a material and an immaterial component. The material component comprises various structures that belong to the whole structure and not to any of its elements per se. The immaterial (ideal) component of the matrix includes social norms and rules regulating network elements' behavior. These behavioral rules can be described in terms of algorithms. Algorithmization enables modeling the behavior of various network structures, particularly of neuron networks and their artificial analogs.

  7. Advanced composite structural concepts and material technologies for primary aircraft structures

    Science.gov (United States)

    Jackson, Anthony

    1991-01-01

    Structural weight savings using advanced composites have been demonstrated for many years. Most military aircraft today use these materials extensively and Europe has taken the lead in their use in commercial aircraft primary structures. A major inhibiter to the use of advanced composites in the United States is cost. Material costs are high and will remain high relative to aluminum. The key therefore lies in the significant reduction in fabrication and assembly costs. The largest cost in most structures today is assembly. As part of the NASA Advanced Composite Technology Program, Lockheed Aeronautical Systems Company has a contract to explore and develop advanced structural and manufacturing concepts using advanced composites for transport aircraft. Wing and fuselage concepts and related trade studies are discussed. These concepts are intended to lower cost and weight through the use of innovative material forms, processes, structural configurations and minimization of parts. The approach to the trade studies and the downselect to the primary wing and fuselage concepts is detailed. The expectations for the development of these concepts is reviewed.

  8. High-beta linac structures

    International Nuclear Information System (INIS)

    Schriber, S.O.

    1979-01-01

    Accelerating structures for high-beta linacs that have been and are in use are reviewed in terms of their performance. Particular emphasis is given to room-temperature structures and the disk-and-washer structure. The disk-and-washer structure has many attractive features that are discussed for pulsed high-gradient linacs, for 100% duty-cycle medium-gradient linacs and for high-current linacs requiring maximal amounts of stored energy in the electric fields available to the beam

  9. Cell packing structures

    KAUST Repository

    Pottmann, Helmut; Jiang, Caigui; Hö binger, Mathias; Wang, Jun; Bompas, Philippe; Wallner, Johannes

    2015-01-01

    optimization schemes for the computation of quad-based support structures. Hex-dominant structures may be designed via Voronoi tessellations, power diagrams, sphere packings and various extensions of these concepts. Apart from the obvious application as load

  10. Transient electromagnetic and dynamic structural analyses of a blanket structure with coupling effects

    Energy Technology Data Exchange (ETDEWEB)

    Koganezawa, K. [Mitsubishi Atomic Power Industries, Inc., Yokohama (Japan); Kushiyama, M. [Mitsubishi Atomic Power Industries, Inc., Yokohama (Japan); Niikura, S. [Mitsubishi Atomic Power Industries, Inc., Yokohama (Japan); Kudough, F. [Mitsubishi Atomic Power Industries, Inc., Yokohama (Japan); Onozuka, M. [Mitsubishi Heavy Industries Ltd., Yokohama (Japan); Koizumi, K. [Japan Atomic Energy Research Inst., Ibaraki (Japan)

    1995-12-31

    Transient electromagnetic and dynamic structural analyses of a blanket structure in the fusion experimental reactor (FER) under a plasma disruption event and a vertical displacement event (VDE) have been performed to investigate the dynamic structural characteristics and the feasibility of the structure. Coupling effects between eddy currents and dynamic deflections have also been taken into account in these analyses. In this study, the inboard blanket was employed because of our computer memory limitation. A 1/192 segment model of a full torus was analyzed using the analytical code, EDDYCUFF. In the plasma disruption event, the maximum magnetic pressure caused by eddy currents and poloidal fields was 1.2MPa. The maximum stress intensity by this magnetic pressure was 114MPa. In the VDE, the maximum magnetic pressure was 2.4MPa and the maximum stress intensity was 253MPa. This stress was somewhat beyond the allowable stress limit. Therefore, the blanket structure and support design should be reviewed to reduce the stress to a suitable value. In summary, the dynamic structural characteristics and design issues of the blanket structure have been identified. (orig.).

  11. Structure-mediated nanoscopy

    DEFF Research Database (Denmark)

    Glückstad, Jesper; Bañas, Andrew Rafael; Aabo, Thomas

    2013-01-01

    of optimal light-sculpting techniques [4] with the use of optimized shapes in micro-robotics structures [5]. Micro-fabrication processes such as two-photon photo-polymerization offer three-dimensional resolutions for creating custom-designed monolithic microstructures that can be equipped with optical...... that are utilized in conventional optical trapping and manipulation. We took this approach to extend the opto-mechanical light-force driven capabilities by including functionalised mechanisms to the fabricated monolithic structures. Aided by collaborators who fabricated test structures with built-in waveguides...

  12. Quantification of the Value of Structural Health Monitoring Information for Fatigue Deteriorating Structural Systems

    DEFF Research Database (Denmark)

    Thöns, Sebastian; Schneider, Ronald; Faber, Michael Havbro

    2015-01-01

    This paper addresses the quantification of the value of structural health monitoring (SHM) before its implementation for structural systems on the basis of its Value of Information (VoI). The value of SHM is calculated utilizing the Bayesian pre-posterior decision analysis modelling the structural...... life cycle performance, the integrity management and the structural risks. The relevance and precision of SHM information for the reduction of the structural system risks and the expected cost of the structural integrity management throughout the life cycle constitutes the value of SHM...... and is quantified with this framework. The approach is focused on fatigue deteriorating structural steel systems for which a continuous resistance deterioration formulation is introduced. In a case study, the value of SHM for load monitoring is calculated for a Daniels system subjected to fatigue deterioration...

  13. Structure problems in the analog computation; Problemes de structure dans le calcul analogique

    Energy Technology Data Exchange (ETDEWEB)

    Braffort, P.L. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1957-07-01

    The recent mathematical development showed the importance of elementary structures (algebraic, topological, etc.) in abeyance under the great domains of classical analysis. Such structures in analog computation are put in evidence and possible development of applied mathematics are discussed. It also studied the topological structures of the standard representation of analog schemes such as additional triangles, integrators, phase inverters and functions generators. The analog method gives only the function of the variable: time, as results of its computations. But the course of computation, for systems including reactive circuits, introduces order structures which are called 'chronological'. Finally, it showed that the approximation methods of ordinary numerical and digital computation present the same structure as these analog computation. The structure analysis permits fruitful comparisons between the several domains of applied mathematics and suggests new important domains of application for analog method. (M.P.)

  14. Structure problems in the analog computation; Problemes de structure dans le calcul analogique

    Energy Technology Data Exchange (ETDEWEB)

    Braffort, P L [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1957-07-01

    The recent mathematical development showed the importance of elementary structures (algebraic, topological, etc.) in abeyance under the great domains of classical analysis. Such structures in analog computation are put in evidence and possible development of applied mathematics are discussed. It also studied the topological structures of the standard representation of analog schemes such as additional triangles, integrators, phase inverters and functions generators. The analog method gives only the function of the variable: time, as results of its computations. But the course of computation, for systems including reactive circuits, introduces order structures which are called 'chronological'. Finally, it showed that the approximation methods of ordinary numerical and digital computation present the same structure as these analog computation. The structure analysis permits fruitful comparisons between the several domains of applied mathematics and suggests new important domains of application for analog method. (M.P.)

  15. Structured automated code checking through structural components and systems engineering

    NARCIS (Netherlands)

    Coenders, J.L.; Rolvink, A.

    2014-01-01

    This paper presents a proposal to employ the design computing methodology proposed as StructuralComponents (Rolvink et al [6] and van de Weerd et al [7]) as a method to perform a digital verification process to fulfil the requirements related to structural design and engineering as part of a

  16. Nonlinear dynamic analysis of framed structures including soil-structure interaction effects

    International Nuclear Information System (INIS)

    Mahmood, M.N.; Ahmed, S.Y.

    2008-01-01

    The role of oil-structure interaction on seismic behavior of reinforced concrete structures is investigated in this paper. A finite element approach has been adopted to model the interaction system that consists of the reinforced concrete plane frame, soil deposit and interface which represents the frictional between foundation of the structure and subsoil. The analysis is based on the elasto-plastic behavior of the frame members (beams and columns) that is defined by the ultimate axial force-bending moment interaction curve, while the cap model is adopted to govern the elasto-plastic behavior of the soil material. Mohr-Coulomb failure law is used to determine the initiation of slippage at the interface, while the separation is assumed to determine the initiation of slippage at the interface, while the separation is assumed to occur when the stresses at the interface becomes tension stresses. New-Mark's Predictor-Corrector algorithm is adopted for nonlinear dynamic analysis. The main aim of present work is to evaluate the sensitivity of structures to different behavior of the soil and interface layer when subjected to an earthquake excitation. Predicted results of the dynamic analysis of the interaction system indicate that the soil-structure interaction problem can have beneficial effects on the structural behavior when different soil models (elastic and elasto-plastic) and interface conditions (perfect bond and permitted slip)are considered. (author)

  17. Identification of similar regions of protein structures using integrated sequence and structure analysis tools

    Directory of Open Access Journals (Sweden)

    Heiland Randy

    2006-03-01

    Full Text Available Abstract Background Understanding protein function from its structure is a challenging problem. Sequence based approaches for finding homology have broad use for annotation of both structure and function. 3D structural information of protein domains and their interactions provide a complementary view to structure function relationships to sequence information. We have developed a web site http://www.sblest.org/ and an API of web services that enables users to submit protein structures and identify statistically significant neighbors and the underlying structural environments that make that match using a suite of sequence and structure analysis tools. To do this, we have integrated S-BLEST, PSI-BLAST and HMMer based superfamily predictions to give a unique integrated view to prediction of SCOP superfamilies, EC number, and GO term, as well as identification of the protein structural environments that are associated with that prediction. Additionally, we have extended UCSF Chimera and PyMOL to support our web services, so that users can characterize their own proteins of interest. Results Users are able to submit their own queries or use a structure already in the PDB. Currently the databases that a user can query include the popular structural datasets ASTRAL 40 v1.69, ASTRAL 95 v1.69, CLUSTER50, CLUSTER70 and CLUSTER90 and PDBSELECT25. The results can be downloaded directly from the site and include function prediction, analysis of the most conserved environments and automated annotation of query proteins. These results reflect both the hits found with PSI-BLAST, HMMer and with S-BLEST. We have evaluated how well annotation transfer can be performed on SCOP ID's, Gene Ontology (GO ID's and EC Numbers. The method is very efficient and totally automated, generally taking around fifteen minutes for a 400 residue protein. Conclusion With structural genomics initiatives determining structures with little, if any, functional characterization

  18. Coulomb double helical structure

    Science.gov (United States)

    Kamimura, Tetsuo; Ishihara, Osamu

    2012-01-01

    Structures of Coulomb clusters formed by dust particles in a plasma are studied by numerical simulation. Our study reveals the presence of various types of self-organized structures of a cluster confined in a prolate spheroidal electrostatic potential. The stable configurations depend on a prolateness parameter for the confining potential as well as on the number of dust particles in a cluster. One-dimensional string, two-dimensional zigzag structure and three-dimensional double helical structure are found as a result of the transition controlled by the prolateness parameter. The formation of stable double helical structures resulted from the transition associated with the instability of angular perturbations on double strings. Analytical perturbation study supports the findings of numerical simulations.

  19. Un service diocésain de la conservation du patrimoine : l’exemple du diocèse de Cambrai (Nord

    Directory of Open Access Journals (Sweden)

    Caroline Biencourt

    2012-04-01

    Full Text Available Dans le diocèse de Cambrai a été instauré un service diocésain du patrimoine culturel dont la mission est la gestion des patrimoines écrits, mobiliers et immobiliers, propriété de l’association diocésaine ou affecté au culte. Ce retour d’expérience permet de présenter le sens, l’intérêt et les enjeux d’une telle responsabilité en terme de connaissance, de conservation et de valorisation d’un aussi vaste ensemble patrimonial cohérent.The diocese of Cambrai has recently set up its own heritage service. The missions of this service include the conservation of the written heritage of the diocese, its mobile and built heritage and in general the property of the diocesan association or belonging otherwise to the church. The article relates the experience of this service and the interest of its responsibilities in terms of the understanding, the conservation and the interpretation of an extensive but coherent heritage.

  20. Learning Analytics: opportunities for schools

    Directory of Open Access Journals (Sweden)

    Giovanni Fulantelli

    2014-12-01

    Full Text Available La valutazione delle esperienze di apprendimento che avvengono in ambienti in cui le interazioni sono mediate dalle tecnologie è una sfida ardua che deve essere affrontata con approcci adeguati. Le tecniche di Learning Analytics si sono sviluppate recentemente con l’obiettivo di fornire gli strumenti necessari per ottimizzare le esperienze di apprendimento. Queste tecniche supportano i docenti nel prendere tempestivamente quelle decisioni che rendono il processo didattico più efficace, permettendo di intervenire sull’intero processo o sui singoli studenti in modo personalizzato. Sebbene le tecniche di Learning Analytics si siano sviluppate principalmente nei contesti di alta formazione online, questo articolo mette in evidenza come l’impiego di tali tecniche può portare benefici anche nei contesti scolastici. Di fatto, in questi contesti, le tecnologie sono sempre più utilizzate per supportare le esperienze di apprendimento formali e informali, come quelle basate su dispositivi mobili, serious game e social network, e i dati generati sono sempre più numerosi, richiedendo nuovi approcci di analisi che traggono vantaggio dall’impiego delle tecniche di Learning Analytics.