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Sample records for bacterial production measurements

  1. Using the overlay assay to qualitatively measure bacterial production of and sensitivity to pneumococcal bacteriocins.

    Science.gov (United States)

    Maricic, Natalie; Dawid, Suzanne

    2014-09-30

    Streptococcus pneumoniae colonizes the highly diverse polymicrobial community of the nasopharynx where it must compete with resident organisms. We have shown that bacterially produced antimicrobial peptides (bacteriocins) dictate the outcome of these competitive interactions. All fully-sequenced pneumococcal strains harbor a bacteriocin-like peptide (blp) locus. The blp locus encodes for a range of diverse bacteriocins and all of the highly conserved components needed for their regulation, processing, and secretion. The diversity of the bacteriocins found in the bacteriocin immunity region (BIR) of the locus is a major contributor of pneumococcal competition. Along with the bacteriocins, immunity genes are found in the BIR and are needed to protect the producer cell from the effects of its own bacteriocin. The overlay assay is a quick method for examining a large number of strains for competitive interactions mediated by bacteriocins. The overlay assay also allows for the characterization of bacteriocin-specific immunity, and detection of secreted quorum sensing peptides. The assay is performed by pre-inoculating an agar plate with a strain to be tested for bacteriocin production followed by application of a soft agar overlay containing a strain to be tested for bacteriocin sensitivity. A zone of clearance surrounding the stab indicates that the overlay strain is sensitive to the bacteriocins produced by the pre-inoculated strain. If no zone of clearance is observed, either the overlay strain is immune to the bacteriocins being produced or the pre-inoculated strain does not produce bacteriocins. To determine if the blp locus is functional in a given strain, the overlay assay can be adapted to evaluate for peptide pheromone secretion by the pre-inoculated strain. In this case, a series of four lacZ-reporter strains with different pheromone specificity are used in the overlay.

  2. Viral and bacterial production in the North Water: in situ measurements, batch-culture experiments and characterization and distribution of a virus host system

    Science.gov (United States)

    Middelboe, Mathias; Nielsen, Torkel G.; Bjørnsen, Peter K.

    Growth and viral lysis of bacterioplankton at subzero temperatures were measured in the North Water polynya in July 1998. In situ measurements of bacterial carbon consumption in surface waters ranged from 15 to 63 μg C l -1 d -1 in the eastern and 6 to 7 μg C l -1 d -1 in the northern part of the polynya. Both bacterial abundance and activity appeared to increase in response to the decay of the phytoplankton bloom that developed in the North Water. Organic carbon was the limiting substrate for bacteria in the polynya since addition of glucose, but not inorganic nutrients, to batch cultures increased both the carrying capacity of the substrate and the growth rate of the bacteria. Bacterial growth rates ranged from 0.11 to 0.40 d -1, corresponding to bacterial generation times of 1.7-6.3 d. The in situ viral production rate was estimated both from the frequency of visibly infected cells and from the rate of viral production in batch cultures; it ranged from 0.04 to 0.52 d -1 and from 0.25 to 0.47 d -1, respectively. From 6% to 28% of bacterial production was found to be lost due to viral lysis. The average virus-bacteria ratio was 5.1±3.1, with the abundance of viruses being correlated positively with bacterial production. A Pseudoalteromonas sp. bacterial host and an infective virus were isolated from the polynya; characteristics and distribution of the virus-host system were examined. The Pseudoalteromonas sp. showed psychrotolerant growth and sustained significant production of viruses at 0°C. The virus-host system was found throughout the polynya. Overall the results suggested that a large amount of organic carbon released during the development and breakdown of the spring phytoplankton bloom was consumed by planktonic bacteria and that the microbial food web was an important and dynamic component of the planktonic food web in the North Water.

  3. Production of bacterial cellulose from alternate feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    D. N. Thompson; M. A. Hamilton

    2000-05-07

    Production of bacterial cellulose by Acetobacter xylinum ATCC 10821 and 23770 in static cultures was tested from unamended food process effluents. Effluents included low- and high-solids potato effluents (LS and HS), cheese whey permeate (CW), and sugar beet raffinate (CSB). Strain 23770 produced 10% less cellulose from glucose than did 10821, and diverted more glucose to gluconate. Unamended HS, CW, and CSB were unsuitable for cellulose production by either strain, while LS was unsuitable for production by 10821. However, 23770 produced 17% more cellulose from LS than from glucose, indicating unamended LS could serve as a feedstock for bacterial cellulose.

  4. Production of Bacterial Cellulose from Alternate Feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, David Neil; Hamilton, Melinda Ann

    2000-05-01

    Production of bacterial cellulose by Acetobacter xylinum ATCC 10821 and 23770 in static cultures was tested from unamended food process effluents. Effluents included low- and high-solids potato effluents (LS & HS), cheese whey permeate (CW), and sugar beet raffinate (CSB). Strain 23770 produced 10% less cellulose from glucose than did 10821, and diverted more glucose to gluconate. Unamended HS, CW, and CSB were unsuitable for cellulose production by either strain, while LS was unsuitable for production by 10821. However, 23770 produced 17% more cellulose from LS than from glucose, indicating unamended LS could serve as a feedstock for bacterial cellulose.

  5. PRODUCTION AND CHARACTERIZATION OF ECONOMICAL BACTERIAL CELLULOSE

    OpenAIRE

    Houssni El-Saied; Ahmed I. El-Diwany; Altaf H. Bast; Nagwa A. Atwa; Dina E. El-Ghwas

    2008-01-01

    The present study investigates the economical production of bacterial cellulose (BC) by Gluconacetobacter subsp. Xylinus (ATCC 10245) in 250 ml Erlenmeyer flasks cultivated under static conditions. The fermentation media used contained food industrial by-product liquors, such as black strap molasses solution and corn steep liquor (CSL), which represents some of the most economical carbon and nitrogen sources. However, because of the presence of undesirable components in molasses (such as colo...

  6. PRODUCTION AND CHARACTERIZATION OF ECONOMICAL BACTERIAL CELLULOSE

    Directory of Open Access Journals (Sweden)

    Houssni El-Saied

    2008-11-01

    Full Text Available The present study investigates the economical production of bacterial cellulose (BC by Gluconacetobacter subsp. Xylinus (ATCC 10245 in 250 ml Erlenmeyer flasks cultivated under static conditions. The fermentation media used contained food industrial by-product liquors, such as black strap molasses solution and corn steep liquor (CSL, which represents some of the most economical carbon and nitrogen sources. However, because of the presence of undesirable components in molasses (such as coloring substances, heavy metals, and other compounds that may act as inhibitors, and in order to eliminate them, crude molasses has been treated with an acid, as an attempt to increase BC productivity. The amount of BC produced using these carbon and nitrogen sources was determined and compared to that produced using previously reported fermentation media. The characterizations of the bacterial cellulose (BC pellicles obtained using either conventional or by-product media were studied by thermal and spectral techniques and compared to those of plant-derived cellulose such as cotton linter, viscose pulp, and microcrystalline cellulose.

  7. Bacterial production of the biodegradable plastics polyhydroxyalkanoates.

    Science.gov (United States)

    Urtuvia, Viviana; Villegas, Pamela; González, Myriam; Seeger, Michael

    2014-09-01

    Petroleum-based plastics constitute a major environmental problem due to their low biodegradability and accumulation in various environments. Therefore, searching for novel biodegradable plastics is of increasing interest. Microbial polyesters known as polyhydroxyalkanoates (PHAs) are biodegradable plastics. Life cycle assessment indicates that PHB is more beneficial than petroleum-based plastics. In this report, bacterial production of PHAs and their industrial applications are reviewed and the synthesis of PHAs in Burkholderia xenovorans LB400 is described. PHAs are synthesized by a large number of microorganisms during unbalanced nutritional conditions. These polymers are accumulated as carbon and energy reserve in discrete granules in the bacterial cytoplasm. 3-hydroxybutyrate and 3-hydroxyvalerate are two main PHA units among 150 monomers that have been reported. B. xenovorans LB400 is a model bacterium for the degradation of polychlorobiphenyls and a wide range of aromatic compounds. A bioinformatic analysis of LB400 genome indicated the presence of pha genes encoding enzymes of pathways for PHA synthesis. This study showed that B. xenovorans LB400 synthesize PHAs under nutrient limitation. Staining with Sudan Black B indicated the production of PHAs by B. xenovorans LB400 colonies. The PHAs produced were characterized by GC-MS. Diverse substrates for the production of PHAs in strain LB400 were analyzed.

  8. Engineering microbial hosts for production of bacterial natural products.

    Science.gov (United States)

    Zhang, Mingzi M; Wang, Yajie; Ang, Ee Lui; Zhao, Huimin

    2016-08-27

    Covering up to end 2015Microbial fermentation provides an attractive alternative to chemical synthesis for the production of structurally complex natural products. In most cases, however, production titers are low and need to be improved for compound characterization and/or commercial production. Owing to advances in functional genomics and genetic engineering technologies, microbial hosts can be engineered to overproduce a desired natural product, greatly accelerating the traditionally time-consuming strain improvement process. This review covers recent developments and challenges in the engineering of native and heterologous microbial hosts for the production of bacterial natural products, focusing on the genetic tools and strategies for strain improvement. Special emphasis is placed on bioactive secondary metabolites from actinomycetes. The considerations for the choice of host systems will also be discussed in this review. PMID:27072804

  9. Measurement of Behavioral Evolution in Bacterial Populations

    Science.gov (United States)

    Austin, Robert

    2013-03-01

    A curious aspect of bacterial behavior under stress is the induction of filamentation: the anomalous growth of certain bacteria in which cells continue to elongate but do not divide into progeny. We show that E.coli under the influence of the genotoxic antibiotic ciprofloxacin have robust filamentous growth, which provides individual bacteria a mesoscopic niche for evolution until resistant progeny can bud off and propagate. Hence, filamentation is a form of genomic amplification where even a single, isolated bacteria can have access to multiple genomes. We propose a model that predicts that the first arrival time of the normal sized progeny should follow a Gompertz distribution with the mean first arrival time proportional to the elongation rate of filament. These predictions agree with our experimental measurements. Finally, we suggest bacterial filament growth and budding has many similarities to tumor growth and metastasis and can serve as a simpler model to study those complicated processes. Sponsored by the NCI/NIH Physical Sciences Oncology Centers

  10. Bacterial productivity in the Prydz Bay and its adjacent waters,Antarctic

    Institute of Scientific and Technical Information of China (English)

    邱雨生; 黄奕普; 陈敏; 刘广山

    2004-01-01

    Bacterial productivity was measured using 3H-thymidine methods in the Prydz Bay and its adjacent waters in the Southern Ocean during the 16th National Antarctic Research Expedition of China (CHINARE). The results showed that bacteted for the Ross Sea. The mean ratio of bacterial productivity to primary productivity in our study areas was 41%. The general characteristics in the vertical profiles showed a subsurface maximum at most of the stations, which was also consistent with those observed in the other sea areas in the Southern Ocean. The spatial distribution of bacterial productivity and dissolved organic carbon in the surface waters showed that their variations were inversely correlative. The relationship among bacterial productivity, primary productivity and dissolved organic carbon suggested that bacterial productivity in the Prydz Bay and its adjacent water was influenced mostly by phytoplankton activities and the hydrologic conditions.

  11. How to Measure Export via Bacterial Multidrug Resistance Efflux Pumps

    Science.gov (United States)

    Blair, Jessica M. A.

    2016-01-01

    ABSTRACT Bacterial multidrug resistance (MDR) efflux pumps are an important mechanism of antibiotic resistance and are required for many pathogens to cause infection. They are also being harnessed to improve microbial biotechnological processes, including biofuel production. Therefore, scientists of many specialties must be able to accurately measure efflux activity. However, myriad methodologies have been described and the most appropriate method is not always clear. Within the scientific literature, many methods are misused or data arising are misinterpreted. The methods for measuring efflux activity can be split into two groups, (i) those that directly measure efflux and (ii) those that measure the intracellular accumulation of a substrate, which is then used to infer efflux activity. Here, we review the methods for measuring efflux and explore the most recent advances in this field, including single-cell or cell-free technologies and mass spectrometry, that are being used to provide more detailed information about efflux pump activity. PMID:27381291

  12. How to Measure Export via Bacterial Multidrug Resistance Efflux Pumps.

    Science.gov (United States)

    Blair, Jessica M A; Piddock, Laura J V

    2016-01-01

    Bacterial multidrug resistance (MDR) efflux pumps are an important mechanism of antibiotic resistance and are required for many pathogens to cause infection. They are also being harnessed to improve microbial biotechnological processes, including biofuel production. Therefore, scientists of many specialties must be able to accurately measure efflux activity. However, myriad methodologies have been described and the most appropriate method is not always clear. Within the scientific literature, many methods are misused or data arising are misinterpreted. The methods for measuring efflux activity can be split into two groups, (i) those that directly measure efflux and (ii) those that measure the intracellular accumulation of a substrate, which is then used to infer efflux activity. Here, we review the methods for measuring efflux and explore the most recent advances in this field, including single-cell or cell-free technologies and mass spectrometry, that are being used to provide more detailed information about efflux pump activity. PMID:27381291

  13. Electrical conductivity measurements of bacterial nanowires from Pseudomonas aeruginosa

    Science.gov (United States)

    Maruthupandy, Muthusamy; Anand, Muthusamy; Maduraiveeran, Govindhan; Sait Hameedha Beevi, Akbar; Jeeva Priya, Radhakrishnan

    2015-12-01

    The extracellular appendages of bacteria (flagella) that transfer electrons to electrodes are called bacterial nanowires. This study focuses on the isolation and separation of nanowires that are attached via Pseudomonas aeruginosa bacterial culture. The size and roughness of separated nanowires were measured using transmission electron microscopy (TEM) and atomic force microscopy (AFM), respectively. The obtained bacterial nanowires indicated a clear image of bacterial nanowires measuring 16 nm in diameter. The formation of bacterial nanowires was confirmed by microscopic studies (AFM and TEM) and the conductivity nature of bacterial nanowire was investigated by electrochemical techniques. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), which are nondestructive voltammetry techniques, suggest that bacterial nanowires could be the source of electrons—which may be used in various applications, for example, microbial fuel cells, biosensors, organic solar cells, and bioelectronic devices. Routine analysis of electron transfer between bacterial nanowires and the electrode was performed, providing insight into the extracellular electron transfer (EET) to the electrode. CV revealed the catalytic electron transferability of bacterial nanowires and electrodes and showed excellent redox activities. CV and EIS studies showed that bacterial nanowires can charge the surface by producing and storing sufficient electrons, behave as a capacitor, and have features consistent with EET. Finally, electrochemical studies confirmed the development of bacterial nanowires with EET. This study suggests that bacterial nanowires can be used to fabricate biomolecular sensors and nanoelectronic devices.

  14. Plant Natural Products Targeting Bacterial Virulence Factors.

    Science.gov (United States)

    Silva, Laura Nunes; Zimmer, Karine Rigon; Macedo, Alexandre José; Trentin, Danielle Silva

    2016-08-24

    Decreased antimicrobial efficiency has become a global public health issue. The paucity of new antibacterial drugs is evident, and the arsenal against infectious diseases needs to be improved urgently. The selection of plants as a source of prototype compounds is appropriate, since plant species naturally produce a wide range of secondary metabolites that act as a chemical line of defense against microorganisms in the environment. Although traditional approaches to combat microbial infections remain effective, targeting microbial virulence rather than survival seems to be an exciting strategy, since the modulation of virulence factors might lead to a milder evolutionary pressure for the development of resistance. Additionally, anti-infective chemotherapies may be successfully achieved by combining antivirulence and conventional antimicrobials, extending the lifespan of these drugs. This review presents an updated discussion of natural compounds isolated from plants with chemically characterized structures and activity against the major bacterial virulence factors: quorum sensing, bacterial biofilms, bacterial motility, bacterial toxins, bacterial pigments, bacterial enzymes, and bacterial surfactants. Moreover, a critical analysis of the most promising virulence factors is presented, highlighting their potential as targets to attenuate bacterial virulence. The ongoing progress in the field of antivirulence therapy may therefore help to translate this promising concept into real intervention strategies in clinical areas. PMID:27437994

  15. Bacterivory by heterotrophic nanoflagellates and bacterial production in sediments of a freshwater littoral system

    NARCIS (Netherlands)

    Starink, Mathieu; Bär-Gilissen, M.J.; Bak, R.P.M.; Cappenberg, T.E.

    1996-01-01

    We made simultaneous measurements of benthic bacterial production, using [H-3]thymidine assays, and bacterivory by benthic heterotrophic nanoflagellates (HNAN), using fluorescently labeled bacteria. Sediment samples were collected at two stations in a eutrophic freshwater littoral in different seaso

  16. Primary and Bacterial Secondary Production in a Southwestern Reservoir

    OpenAIRE

    Chrzanowski, Thomas H.; Hubbard, James G

    1988-01-01

    Rates of primary and bacterial secondary production in Lake Arlington, Texas, were determined. The lake is a warm (annual temperature range, 7 to 32°C), shallow, monomictic reservoir with limited macrophyte development in the littoral zone. Samples were collected from six depths within the photic zone from a site located over the deepest portion of the lake. Primary production and bacterial production were calculated from NaH14CO3 and [methyl-3H]thymidine incorporation, respectively. Peak ins...

  17. Primary and Bacterial Secondary Production in a Southwestern Reservoir

    Science.gov (United States)

    Chrzanowski, Thomas H.; Hubbard, James G.

    1988-01-01

    Rates of primary and bacterial secondary production in Lake Arlington, Texas, were determined. The lake is a warm (annual temperature range, 7 to 32°C), shallow, monomictic reservoir with limited macrophyte development in the littoral zone. Samples were collected from six depths within the photic zone from a site located over the deepest portion of the lake. Primary production and bacterial production were calculated from NaH14CO3 and [methyl-3H]thymidine incorporation, respectively. Peak instantaneous production ranged between 14.8 and 220.5 μg of C liter−1 h−1. There were two distinct periods of high rates of production. From May through July, production near the metalimnion exceeded 100 μg of C liter−1 h−1. During holomixis, production throughout the water column was in excess of 100 μg of C liter−1 h−1 and above 150 μg of C liter−1 h−1 near the surface. Annual areal primary production was 588 g of C m−2. Bacterial production was markedly seasonal. Growth rates during late fall through spring were typically around 0.002 h−1, and production rates were typically 5 μg of C liter−1 h−1. Growth rates were higher during warmer parts of the year and reached 0.03 h−1 by August. The maximum instantaneous rate of bacterial production was approximately 45 μg of C liter−1 h−1. Annual areal bacterial production was 125 g of C m−2. Temporal and spatial distributions of bacterial numbers and activities coincided with temporal and spatial distributions of primary production. Areal primary and bacterial secondary production were highly correlated (r = 0.77, n = 15, P < 0.002). PMID:16347577

  18. Estimation of bacterial hydrogen sulfide production in vitro

    Directory of Open Access Journals (Sweden)

    Amina Basic

    2015-06-01

    Full Text Available Oral bacterial hydrogen sulfide (H2S production was estimated comparing two different colorimetric methods in microtiter plate format. High H2S production was seen for Fusobacterium spp., Treponema denticola, and Prevotella tannerae, associated with periodontal disease. The production differed between the methods indicating that H2S production may follow different pathways.

  19. Intermittency measurement in two dimensional bacterial turbulence

    CERN Document Server

    Qiu, Xiang; Huang, Yongxiang; Chen, Ming; Lu, Zhiming; Liu, Yulu; Zhou, Quan

    2016-01-01

    In this paper, an experimental velocity database of a bacterial collective motion , e.g., \\textit{B. subtilis}, in turbulent phase with volume filling fraction $84\\%$ provided by Professor Goldstein at the Cambridge University UK, was analyzed to emphasize the scaling behavior of this active turbulence system. This was accomplished by performing a Hilbert-based methodology analysis to retrieve the scaling property without the $\\beta-$limitation. A dual-power-law behavior separated by the viscosity scale $\\ell_{\

  20. Bacterial production in subarctic peatland lakes enriched by thawing permafrost

    Science.gov (United States)

    Deshpande, Bethany N.; Crevecoeur, Sophie; Matveev, Alex; Vincent, Warwick F.

    2016-08-01

    Peatlands extend over vast areas of the northern landscape. Within some of these areas, lakes and ponds are changing in size as a result of permafrost thawing and erosion, resulting in mobilization of the carbon-rich peatland soils. Our aims in the present study were to characterize the particle, carbon and nutrient regime of a set of thermokarst (thaw) lakes and their adjacent peatland permafrost soils in a rapidly degrading landscape in subarctic Québec, Canada, and by way of fluorescence microscopy, flow cytometry, production measurements and an in situ enrichment experiment, determine the bacterial characteristics of these waters relative to other thaw lakes and rock-basin lakes in the region. The soil active layer in a degrading palsa (peatland permafrost mound) adjacent to one of the lakes contained an elevated carbon content (51 % of dry weight), high C : N ratios (17 : 1 by mass), and large stocks of other elements including N (3 % of dry weight), Fe (0.6 %), S (0.5 %), Ca (0.5 %) and P (0.05 %). Two permafrost cores were obtained to a depth of 2.77 m in the palsa, and computerized tomography scans of the cores confirmed that they contained high concentrations (> 80 %) of ice. Upon thawing, the cores released nitrate and dissolved organic carbon (from all core depths sampled), and soluble reactive phosphorus (from bottom depths), at concentrations well above those in the adjacent lake waters. The active layer soil showed a range of particle sizes with a peak at 229 µm, and this was similar to the distribution of particles in the upper permafrost cores. The particle spectrum for the lake water overlapped with those for the soil, but extended to larger (surface water) or finer (bottom water) particles. On average, more than 50 % of the bacterial cells and bacterial production was associated with particles > 3 µm. This relatively low contribution of free-living cells (operationally defined as the rock-basin lakes (average ± SE of 25 ± 6 %). However, a

  1. Bacterial Cellulose Production by Acetobacter xylinum Strains from Agricultural Waste Products

    Science.gov (United States)

    Kongruang, Sasithorn

    Bacterial cellulose is a biopolysaccharide produced from the bacteria, Acetobacter xylinum. Static batch fermentations for bacterial cellulose production were studied in coconut and pineapple juices under 30 °C in 5-1 fermenters by using three Acetobacter strains: A. xylinum TISTR 998, A. xylinum TISTR 975, and A. xylinum TISTR 893. Experiments were carried out to compare bacterial cellulose yields along with growth kinetic analysis. Results showed that A. xylinum TISTR 998 produced a bacterial cellulose yield of 553.33 g/l, while A. xylinum TISTR 893 produced 453.33 g/l and A. xylinum TISTR 975 produced 243.33 g/l. In pineapple juice, the yields for A. xylinum TISTR 893, 975, and 998 were 576.66, 546.66, and 520 g/l, respectively. The strain TISTR 998 showed the highest productivity when using coconut juice. Morphological properties of cellulose pellicles, in terms of texture and color, were also measured, and the textures were not significantly different among treatments.

  2. Measurement of bacterial ingestion and killing by macrophages.

    Science.gov (United States)

    Campbell, P A; Canono, B P; Drevets, D A

    2001-05-01

    This unit presents fairly simple assays for measuring the binding of bacteria to macrophages, internalization of bacteria (also called ingestion or phagocytosis), and bacterial killing by macrophages. The first basic protocol describes how to measure the ability of macrophages to ingest bacteria. Because it is critical to remove residual extracellular organisms, the protocol presents two alternative steps to accomplish this: a washing procedure and a more stringent method in which cells are sedimented through sucrose. In addition, it is important to distinguish those bacteria truly ingested by a macrophage from those that are bound to, but not internalized by, the cell. A simple but effective way to do this is described in an alternate protocol. The unit also presents two ways to measure the ability of a macrophage to kill bacteria it has internalized. The first is a straightforward assay in which bacterial colonies are enumerated before and after a killing period; a subsequent colony count will indicate whether the bacteria grew within or were killed by the macrophage. The second protocol describes a way to measure bacterial viability based on bacterial metabolism, in which the ability of bacterial dehydrogenases to mediate the reduction of a tetrazolium salt to purple formazan is monitored by measuring absorbance spectrophotometrically.

  3. Bacterial Cellulose Production from Industrial Waste and by-Product Streams

    OpenAIRE

    Erminda Tsouko; Constantina Kourmentza; Dimitrios Ladakis; Nikolaos Kopsahelis; Ioanna Mandala; Seraphim Papanikolaou; Fotis Paloukis; Vitor Alves; Apostolis Koutinas

    2015-01-01

    The utilization of fermentation media derived from waste and by-product streams from biodiesel and confectionery industries could lead to highly efficient production of bacterial cellulose. Batch fermentations with the bacterial strain Komagataeibacter sucrofermentans DSM (Deutsche Sammlung von Mikroorganismen) 15973 were initially carried out in synthetic media using commercial sugars and crude glycerol. The highest bacterial cellulose concentration was achieved when crude glycerol (3.2 g/L)...

  4. Production of extremophilic bacterial cellulase enzymes in aspergillus niger.

    Energy Technology Data Exchange (ETDEWEB)

    Gladden, John Michael

    2013-09-01

    Enzymes can be used to catalyze a myriad of chemical reactions and are a cornerstone in the biotechnology industry. Enzymes have a wide range of uses, ranging from medicine with the production of pharmaceuticals to energy were they are applied to biofuel production. However, it is difficult to produce large quantities of enzymes, especially if they are non-native to the production host. Fortunately, filamentous fungi, such as Aspergillus niger, are broadly used in industry and show great potential for use a heterologous enzyme production hosts. Here, we present work outlining an effort to engineer A. niger to produce thermophilic bacterial cellulases relevant to lignocellulosic biofuel production.

  5. Bioassays for evaluation of medical products derived from bacterial toxins.

    Science.gov (United States)

    Sesardic, Thea

    2012-06-01

    Bioassays play central role in evaluation of biological products and those derived from bacterial toxins often rely exclusively on in vivo models for assurance of safety and potency. This chapter reviews existing regulatory approved methods designed to provide information on potency and safety of complex biological medicines with an insight into strategies considered for alternative procedures.

  6. Bacterial nanocellulose production and application: a 10-year overview.

    Science.gov (United States)

    Jozala, Angela Faustino; de Lencastre-Novaes, Leticia Celia; Lopes, André Moreni; de Carvalho Santos-Ebinuma, Valéria; Mazzola, Priscila Gava; Pessoa-Jr, Adalberto; Grotto, Denise; Gerenutti, Marli; Chaud, Marco Vinicius

    2016-03-01

    Production of bacterial nanocellulose (BNC) is becoming increasingly popular owing to its environmentally friendly properties. Based on this benefit of BNC production, researchers have also begun to examine the capacity for cellulose production through microbial hosts. Indeed, several research groups have developed processes for BNC production, and many studies have been published to date, with the goal of developing methods for large-scale production. During BNC bioproduction, the culture medium represents approximately 30 % of the total cost. Therefore, one important and challenging aspect of the fermentation process is identification of a new cost-effective culture medium that can facilitate the production of high yields within short periods of time, thereby improving BNC production and permitting application of BNC in the biotechnological, medical, pharmaceutical, and food industries. In this review, we addressed different aspects of BNC production, including types of fermentation processes and culture media, with the aim of demonstrating the importance of these parameters. PMID:26743657

  7. Spallation neutron production measurements

    International Nuclear Information System (INIS)

    Measurements of neutron production by the proton bombardment of range-thick targets of lead (Pb) and of tungsten (W) at energies of 0.8, 1.0, 1.2, and 1.4 GeV were made for comparison with calculations based on the computer codes LAHET for neutrons with Eη > 20 MeV and MCNP for Eη ≤ 20 MeV and also to compare with each of two prior experiments dating from about 1965. 2 refs., 7 figs., 4 tabs

  8. Cell wall mechanical properties as measured with bacterial thread made from Bacillus subtilis.

    OpenAIRE

    Mendelson, N H; Thwaites, J J

    1989-01-01

    Engineering approaches used in the study of textile fibers have been applied to the measurement of mechanical properties of bacterial cell walls by using the Bacillus subtilis bacterial thread system. Improved methods have been developed for the production of thread and for measuring its mechanical properties. The best specimens of thread produced from cultures of strain FJ7 grown in TB medium at 20 degrees C varied in diameter by a factor of 1.09 over a 30-mm thread length. The stress-strain...

  9. Factors limiting heterotrophic bacterial production in the southern Pacific Ocean

    Directory of Open Access Journals (Sweden)

    F. Van Wambeke

    2007-10-01

    Full Text Available The role of potential factors limiting bacterial growth was investigated along vertical and longitudinal gradients across the South Eastern Pacific Gyre. The effects of glucose, nitrate, ammonium and phosphate additions on heterotrophic bacterial production (using leucine technique were studied in parallel in unfiltered seawater samples incubated under natural daily irradiance. Longitudinally, the enrichments realized on the subsurface showed three types of responses. From the Marquesas plateau (8° W to approx 125° W, bacteria were not bottom-up controlled, as confirmed by the huge potential of growth in non-enriched seawater (43±24 times in 24 h. Within the Gyre (125° W–95° W, nitrogen alone stimulated leucine incorporation rates by a factor of 5.6±3.6, but rapidly labile carbon (glucose became a second limiting factor (enhancement factor 49±32 when the two elements were added. Finally from the border of the gyre to the Chilean upwelling (95° W–73° W, labile carbon was the only factor stimulating heterotrophic bacterial production. Interaction between phytoplankton and heterotrophic bacterial communities and the direct versus indirect effect of iron and macronutrients on bacterial production were also investigated in four selected sites: two sites on the vicinity of the Marquesas plateau, the centre of the gyre and the Eastern border of the gyre. Both phytoplankton and heterotrophic bacteria were limited by availability of nitrogen within the gyre, but not by iron. While iron limited phytoplankton at Marquesas plateau and at the eastern border of the gyre, heterotrophic bacteria were only limited by availability of labile DOC in those environments.

  10. Thiosulfate as a metabolic product: the bacterial fermentation of taurine.

    Science.gov (United States)

    Denger, K; Laue, H; Cook, A M

    1997-10-01

    Thiosulfate (S2O32-) is a natural product that is widely utilized in natural ecosystems as an electron sink or as an electron donor. However, the major biological source(s) of this thiosulfate is unknown. We present the first report that taurine (2-aminoethanesulfonate), the major mammalian solute, is subject to fermentation. This bacterial fermentation was found to be catalyzed by a new isolate, strain GKNTAU, a strictly anaerobic, gram-positive, motile rod that formed subterminal spores. Thiosulfate was a quantitative fermentation product. The other fermentation products were ammonia and acetate, and all could be formed by cell-free extracts.

  11. Bacterial Cellulose Production from Industrial Waste and by-Product Streams

    Science.gov (United States)

    Tsouko, Erminda; Kourmentza, Constantina; Ladakis, Dimitrios; Kopsahelis, Nikolaos; Mandala, Ioanna; Papanikolaou, Seraphim; Paloukis, Fotis; Alves, Vitor; Koutinas, Apostolis

    2015-01-01

    The utilization of fermentation media derived from waste and by-product streams from biodiesel and confectionery industries could lead to highly efficient production of bacterial cellulose. Batch fermentations with the bacterial strain Komagataeibacter sucrofermentans DSM (Deutsche Sammlung von Mikroorganismen) 15973 were initially carried out in synthetic media using commercial sugars and crude glycerol. The highest bacterial cellulose concentration was achieved when crude glycerol (3.2 g/L) and commercial sucrose (4.9 g/L) were used. The combination of crude glycerol and sunflower meal hydrolysates as the sole fermentation media resulted in bacterial cellulose production of 13.3 g/L. Similar results (13 g/L) were obtained when flour-rich hydrolysates produced from confectionery industry waste streams were used. The properties of bacterial celluloses developed when different fermentation media were used showed water holding capacities of 102–138 g·water/g·dry bacterial cellulose, viscosities of 4.7–9.3 dL/g, degree of polymerization of 1889.1–2672.8, stress at break of 72.3–139.5 MPa and Young’s modulus of 0.97–1.64 GPa. This study demonstrated that by-product streams from the biodiesel industry and waste streams from confectionery industries could be used as the sole sources of nutrients for the production of bacterial cellulose with similar properties as those produced with commercial sources of nutrients. PMID:26140376

  12. Bacterial Cellulose Production from Industrial Waste and by-Product Streams

    Directory of Open Access Journals (Sweden)

    Erminda Tsouko

    2015-07-01

    Full Text Available The utilization of fermentation media derived from waste and by-product streams from biodiesel and confectionery industries could lead to highly efficient production of bacterial cellulose. Batch fermentations with the bacterial strain Komagataeibacter sucrofermentans DSM (Deutsche Sammlung von Mikroorganismen 15973 were initially carried out in synthetic media using commercial sugars and crude glycerol. The highest bacterial cellulose concentration was achieved when crude glycerol (3.2 g/L and commercial sucrose (4.9 g/L were used. The combination of crude glycerol and sunflower meal hydrolysates as the sole fermentation media resulted in bacterial cellulose production of 13.3 g/L. Similar results (13 g/L were obtained when flour-rich hydrolysates produced from confectionery industry waste streams were used. The properties of bacterial celluloses developed when different fermentation media were used showed water holding capacities of 102–138 g·water/g·dry bacterial cellulose, viscosities of 4.7–9.3 dL/g, degree of polymerization of 1889.1–2672.8, stress at break of 72.3–139.5 MPa and Young’s modulus of 0.97–1.64 GPa. This study demonstrated that by-product streams from the biodiesel industry and waste streams from confectionery industries could be used as the sole sources of nutrients for the production of bacterial cellulose with similar properties as those produced with commercial sources of nutrients.

  13. Thiosulfate as a metabolic product: the bacterial fermentation of taurine

    OpenAIRE

    Denger, Karin; Laue, Heike; Cook, Alasdair M.

    1997-01-01

    Thiosulfate (S2O3²-) is a natural product that is widely utilized in natural ecosystems as an electron sink or as an electron donor. However, the major biological source(s) of this thiosulfate is unknown. We present the first report that taurine (2-aminoethanesulfonate), the major mammalian solute, is subject to fermentation. This bacterial fermentation was found to be catalyzed by a new isolate, strain GKNTAU, a strictly anaerobic, gram-positive, motile rod that formed subterminal spores. Th...

  14. Bacterial cellulose biosynthesis: diversity of operons, subunits, products and functions

    OpenAIRE

    Römling, Ute; Galperin, Michael Y

    2015-01-01

    Recent studies of bacterial cellulose biosynthesis, including structural characterization of a functional cellulose synthase complex, provided the first mechanistic insight into this fascinating process. In most studied bacteria, just two subunits, BcsA and BcsB, are necessary and sufficient for the formation of the polysaccharide chain in vitro. Other subunits – which differ among various taxa – affect the enzymatic activity and product yield in vivo by modulating expression of biosynthesis ...

  15. Bacterial Biosensors for Measuring Availability of Environmental Pollutants

    Directory of Open Access Journals (Sweden)

    Jan Roelof van der Meer

    2008-07-01

    Full Text Available Traditionally, pollution risk assessment is based on the measurement of a pollutant’s total concentration in a sample. The toxicity of a given pollutant in the environment, however, is tightly linked to its bioavailability, which may differ significantly from the total amount. Physico-chemical and biological parameters strongly influence pollutant fate in terms of leaching, sequestration and biodegradation. Bacterial sensorreporters, which consist of living micro-organisms genetically engineered to produce specific output in response to target chemicals, offer an interesting alternative to monitoring approaches. Bacterial sensor-reporters detect bioavailable and/or bioaccessible compound fractions in samples. Currently, a variety of environmental pollutants can be targeted by specific biosensor-reporters. Although most of such strains are still confined to the lab, several recent reports have demonstrated utility of bacterial sensing-reporting in the field, with method detection limits in the nanomolar range. This review illustrates the general design principles for bacterial sensor-reporters, presents an overview of the existing biosensor-reporter strains with emphasis on organic compound detection. A specific focus throughout is on the concepts of bioavailability and bioaccessibility, and how bacteria-based sensing-reporting systems can help to improve our basic understanding of the different processes at work.

  16. Vitamin C enhances bacterial cellulose production in Gluconacetobacter xylinus.

    Science.gov (United States)

    Keshk, Sherif M A S

    2014-01-01

    Influence of vitamin C (ascorbic acid) on bacterial cellulose (BC) production and crystal structure was studied using four strains of Gluconacetobacter xylinus (ATCC 10245, IFO 13693, 13772 and 13773). BC productivity of all strains was increased in presence of vitamin C (0.5% w/w), the average BC production reached 0.47 g/30 ml compared with 0.25 g/30 ml without vitamin C. Enhanced productivity is associated with a decrease in gluconic acid concentration that is produced from Gluconacetobacter xylinus during BC production. X-ray results showed that the crystallinity index of BC produced in presence of ascorbic acid was the lowest with remarkable change in d-spacing. These results were confirmed by using solid state (13)CNMR. The increase in BC yield in presence of vitamin C is due to its antioxidant behavior and confirms our past work on lignosulfonate influence on BC.

  17. Bacterial antisense RNAs are mainly the product of transcriptional noise

    Science.gov (United States)

    Lloréns-Rico, Verónica; Cano, Jaime; Kamminga, Tjerko; Gil, Rosario; Latorre, Amparo; Chen, Wei-Hua; Bork, Peer; Glass, John I.; Serrano, Luis; Lluch-Senar, Maria

    2016-01-01

    cis-Encoded antisense RNAs (asRNAs) are widespread along bacterial transcriptomes. However, the role of most of these RNAs remains unknown, and there is an ongoing discussion as to what extent these transcripts are the result of transcriptional noise. We show, by comparative transcriptomics of 20 bacterial species and one chloroplast, that the number of asRNAs is exponentially dependent on the genomic AT content and that expression of asRNA at low levels exerts little impact in terms of energy consumption. A transcription model simulating mRNA and asRNA production indicates that the asRNA regulatory effect is only observed above certain expression thresholds, substantially higher than physiological transcript levels. These predictions were verified experimentally by overexpressing nine different asRNAs in Mycoplasma pneumoniae. Our results suggest that most of the antisense transcripts found in bacteria are the consequence of transcriptional noise, arising at spurious promoters throughout the genome. PMID:26973873

  18. The Bacterial Ghost platform system: production and applications.

    Science.gov (United States)

    Langemann, Timo; Koller, Verena Juliana; Muhammad, Abbas; Kudela, Pavol; Mayr, Ulrike Beate; Lubitz, Werner

    2010-01-01

    The Bacterial Ghost (BG) platform technology is an innovative system for vaccine, drug or active substance delivery and for technical applications in white biotechnology. BGs are cell envelopes derived from Gram-negative bacteria. BGs are devoid of all cytoplasmic content but have a preserved cellular morphology including all cell surface structures. Using BGs as delivery vehicles for subunit or DNA-vaccines the particle structure and surface properties of BGs are targeting the carrier itself to primary antigen-presenting cells. Furthermore, BGs exhibit intrinsic adjuvant properties and trigger an enhanced humoral and cellular immune response to the target antigen. Multiple antigens of the native BG envelope and recombinant protein or DNA antigens can be combined in a single type of BG. Antigens can be presented on the inner or outer membrane of the BG as well as in the periplasm that is sealed during BG formation. Drugs or supplements can also be loaded to the internal lumen or periplasmic space of the carrier. BGs are produced by batch fermentation with subsequent product recovery and purification via tangential flow filtration. For safety reasons all residual bacterial DNA is inactivated during the BG production process by the use of staphylococcal nuclease A and/or the treatment with β-propiolactone. After purification BGs can be stored long-term at ambient room temperature as lyophilized product. The production cycle from the inoculation of the pre-culture to the purified BG concentrate ready for lyophilization does not take longer than a day and thus meets modern criteria of rapid vaccine production rather than keeping large stocks of vaccines. The broad spectrum of possible applications in combination with the comparably low production costs make the BG platform technology a safe and sophisticated product for the targeted delivery of vaccines and active agents as well as carrier of immobilized enzymes for applications in white biotechnology. PMID:21326832

  19. Simultaneous radioassays of bacterial production and mercury methylation in the periphyton of a tropical and a temperate wetland.

    Science.gov (United States)

    Guimarães, J R D; Mauro, J B N; Meili, M; Sundbom, M; Haglund, A L; Coelho-Souza, S A; Hylander, L D

    2006-10-01

    Laboratory radioassays were made to study mercury (Hg) methylation together with bacterial production in the periphyton of two aquatic macrophytes, the submerged Myriophyllum spicatum, from a constructed wetland in Sweden and the floating Eichhornia crassipes, from a eutrophied tropical lake in Brazil. Time course incubations were made by addition of (203)HgCl(2) and the methylmercury formed was extracted at pre-defined time intervals. Bacterial production ((14)C-leucine incorporation) was measured at the same time intervals, with plants removed from parallel incubations made with and without addition of cold HgCl(2). For E. crassipes, higher methylmercury production was observed at elevated bacterial production, whereas for M. spicatum, the bacterial production was significantly lower, and Hg methylation was below the detection limit. The combined results confirm the importance of microbial processes for Hg methylation, although other factors are known to influence this process in complex ways. The addition of Hg did not significantly influence bacterial production, while the incubation temperatures used (25 and 35 degrees C) resulted in different methylation rates. Radiotracer techniques for measurements of bacterial production such as (14)C-leucine uptake can provide useful insights into the Hg cycle in aquatic environments, and our data suggest that they may be used as a proxy of mercury methylation potentials. PMID:16956711

  20. Bacterial cellulose biosynthesis: diversity of operons, subunits, products and functions

    Science.gov (United States)

    Römling, Ute; Galperin, Michael Y.

    2015-01-01

    Summary Recent studies of bacterial cellulose biosynthesis, including structural characterization of a functional cellulose synthase complex, provided the first mechanistic insight into this fascinating process. In most studied bacteria, just two subunits, BcsA and BcsB, are necessary and sufficient for the formation of the polysaccharide chain in vitro. Other subunits – which differ among various taxa – affect the enzymatic activity and product yield in vivo by modulating expression of biosynthesis apparatus, export of the nascent β-D-glucan polymer to the cell surface, and the organization of cellulose fibers into a higher-order structure. These auxiliary subunits play key roles in determining the quantity and structure of the resulting biofilm, which is particularly important for interactions of bacteria with higher organisms that lead to rhizosphere colonization and modulate virulence of cellulose-producing bacterial pathogens inside and outside of host cells. Here we review the organization of four principal types of cellulose synthase operons found in various bacterial genomes, identify additional bcs genes that encode likely components of the cellulose biosynthesis and secretion machinery, and propose a unified nomenclature for these genes and subunits. We also discuss the role of cellulose as a key component of biofilms formed by a variety of free-living and pathogenic bacteria and, for the latter, in the choice between acute infection and persistence in the host. PMID:26077867

  1. Bacterial abundance and production in the central and eastern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, N.; Raghukumar, S.; Gauns, M.

    Seasonal and spatial variations in bacterial and picoplankton abundances and bacterial production (thymidine incorporation rates) were determined in the water column up to 150 m in several stations in the central and eastern Arabian Sea. Higher...

  2. 9 CFR 113.100 - General requirements for inactivated bacterial products.

    Science.gov (United States)

    2010-01-01

    ... bacterial products. 113.100 Section 113.100 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD REQUIREMENTS Inactivated Bacterial Products § 113.100 General requirements for...

  3. Evaluation of in vitro gas production and rumen bacterial populations fermenting corn milling (co)products.

    Science.gov (United States)

    Williams, W L; Tedeschi, L O; Kononoff, P J; Callaway, T R; Dowd, S E; Karges, K; Gibson, M L

    2010-10-01

    The objective of this study was to evaluate the fermentation dynamics of 2 commonly fed corn (co)products in their intact and defatted forms, using the in vitro gas production (IVGP) technique, and to investigate the shifts of the predominant rumen bacterial populations using the 16S rDNA bacterial tag-encoded FLX amplicon pyrosequencing (bTEFAP) technique. The bTEFAP technique was used to determine the bacterial profile of each fermentation time at 24 and 48 h. Bacterial populations were identified at the species level. Species were grouped by substrate affinities (guilds) for cellulose, hemicellulose, pectin, starch, sugars, protein, lipids, and lactate. The 2 (co)products were a dried distillers grain (DDG) plus solubles produced from a low-heat drying process (BPX) and a high-protein DDG without solubles (HP). Chemical analysis revealed that BPX contained about 11.4% ether extract, whereas HP contained only 3.88%. Previous studies have indicated that processing methods, as well as fat content, of corn (co)products directly affect fermentation rate and substrate availability, but little information is available regarding changes in rumen bacterial populations. Fermentation profiles of intact and defatted BPX and HP were compared with alfalfa hay as a standard profile. Defatting before incubation had no effect on total gas production in BPX or HP, but reduced lag time and the fractional rate of fermentation of BPX by at least half, whereas there was no effect for HP. The HP feed supported a greater percentage of fibrolytic and proteolytic bacteria than did BPX. Defatting both DDG increased the fibrolytic (26.8 to 38.7%) and proteolytic (26.1 to 37.2%) bacterial guild populations and decreased the lactate-utilizing bacterial guild (3.06 to 1.44%). Information regarding the fermentation kinetics and bacterial population shifts when feeding corn (co)products may lead to more innovative processing methods that improve feed quality (e.g., deoiling) and consequently

  4. Metabolic flux analysis of Gluconacetobacter xylinus for bacterial cellulose production.

    Science.gov (United States)

    Zhong, Cheng; Zhang, Gui-Cai; Liu, Miao; Zheng, Xin-Tong; Han, Pei-Pei; Jia, Shi-Ru

    2013-07-01

    Metabolic flux analysis was used to reveal the metabolic distributions in Gluconacetobacter xylinus (CGMCC no. 2955) cultured on different carbon sources. Compared with other sources, glucose, fructose, and glycerol could achieve much higher bacterial cellulose (BC) yields from G. xylinus (CGMCC no. 2955). The glycerol led to the highest BC production with a metabolic yield of 14.7 g/mol C, which was approximately 1.69-fold and 2.38-fold greater than that produced using fructose and glucose medium, respectively. The highest BC productivity from G. xylinus CGMCC 2955 was 5.97 g BC/L (dry weight) when using glycerol as the sole carbon source. Metabolic flux analysis for the central carbon metabolism revealed that about 47.96 % of glycerol was transformed into BC, while only 19.05 % of glucose and 24.78 % of fructose were transformed into BC. Instead, when glucose was used as the sole carbon source, 40.03 % of glucose was turned into the by-product gluconic acid. Compared with BC from glucose and fructose, BC from the glycerol medium showed the highest tensile strength at 83.5 MPa, with thinner fibers and lower porosity. As a main byproduct of biodiesel production, glycerol holds great potential to produce BC with superior mechanical and microstructural characteristics.

  5. Bacterial cellulose production from the litchi extract by Gluconacetobacter xylinus.

    Science.gov (United States)

    Yang, Xiao-Yan; Huang, Chao; Guo, Hai-Jun; Xiong, Lian; Luo, Jun; Wang, Bo; Lin, Xiao-Qing; Chen, Xue-Fang; Chen, Xin-De

    2016-01-01

    Although litchi has both nutrient and edible value, the extremely short preservation time limited its further market promotion. To explore processed litchi products with longer preservation time, litchi extract was selected as an alternative feedstock for production of bacterial cellulose (BC). After 2 weeks of static fermentation, 2.53 g/L of the BC membrane was obtained. The trace elements including magnesium (Mg) and sodium (Na) in the litchi extract were partly absorbed in the BC membrane, but no potassium (K) element was detected in it, curiously. Scanning electron microscope (SEM) photographs exhibited an ultrafine network nanostructure for the BC produced in the litchi extract. Analysis of the fourier-transform infrared spectroscopy (FTIR) confirmed the pellicles to be a cellulosic material. Interestingly, X-ray diffraction (XRD) results showed the BC membrane obtained from litchi extract had higher crystallinity of 94.0% than that from HS medium. Overall, the work showed the potential of producing high value-added polymer from litchi resources.

  6. Heterotrophic bacterial production in the South East Pacific: longitudinal trends and coupling with primary production

    Directory of Open Access Journals (Sweden)

    F. Van Wambeke

    2007-08-01

    Full Text Available Spatial variations of heterotrophic bacterial production and phytoplankton primary production were investigated across South East Pacific Ocean (–141° W, –8° S to –72° W, –35° S in November–December 2004. Bacterial production (³H leucine incorporation integrated over the euphotic zone encompassed a wide range of values, from 43 mg C m−2 d−1 in the hyper-oligotrophic South Pacific Gyre to 392 mg C m−2 d−1 in the upwelling off Chile. Within the gyre (120° W, 22° S records of low phytoplankton biomass (7 mg TChla m−2 were obtained and in situ 14C based particulate primary production rates were as low as 153 mg C m−2 d−1, thus equal to the value considered as a limit for primary production under strong oligotrophic conditions. In the South Pacific gyre average rates of ³H leucine incorporation rates, and leucine incorporation rates per cell (5–21 pmol L−1 h−1 and 15–56×10−21 mol cell−1 h−1, respectively, were in the same range as those reported for other oligotrophic sub tropical and temperate waters. Rates of dark community respiration, determined at selected stations across the transect varied in a narrow range (42–97 mmol O2 m−2 d−1, except for one station in the upwelling off Chile (245 mmol O2 m−2 d−1. Bacterial growth efficiencies varied between 5 and 38% and bacterial carbon demand largely exceeded 14C particulate primary production across the South Pacific Ocean. Net community production also revealed negative values in the South Pacific Gyre (–13±20 to –37±40 mmol O2 m−2 d−1. Such imbalances being impossible in this area far from any external input, we discuss the techniques involved for determining the coupling between

  7. In vitro effects of anthocyanidins on sinonasal epithelial nitric oxide production and bacterial physiology

    Science.gov (United States)

    Hariri, Benjamin M.; Payne, Sakeena J.; Chen, Bei; Mansfield, Corrine; Doghramji, Laurel J.; Adappa, Nithin D.; Palmer, James N.; Kennedy, David W.; Niv, Masha Y.

    2016-01-01

    Background: T2R bitter taste receptors play a crucial role in sinonasal innate immunity by upregulating mucociliary clearance and nitric oxide (NO) production in response to bitter gram-negative quorum-sensing molecules in the airway surface liquid. Previous studies showed that phytochemical flavonoid metabolites, known as anthocyanidins, taste bitter and have antibacterial effects. Our objectives were to examine the effects of anthocyanidins on NO production by human sinonasal epithelial cells and ciliary beat frequency, and their impact on common sinonasal pathogens Pseudomonas aeruginosa and Staphylococcus aureus. Methods: Ciliary beat frequency and NO production were measured by using digital imaging of differentiated air-liquid interface cultures prepared from primary human cells isolated from residual surgical material. Plate-based assays were used to determine the effects of anthocyanidins on bacterial swimming and swarming motility. Biofilm formation and planktonic growth were also assessed. Results: Anthocyanidin compounds triggered epithelial cells to produce NO but not through T2R receptors. However, anthocyanidins did not impact ciliary beat frequency. Furthermore, they did not reduce biofilm formation or planktonic growth of P. aeruginosa. In S. aureus, they did not reduce planktonic growth, and only one compound had minimal antibiofilm effects. The anthocyanidin delphinidin and anthocyanin keracyanin were found to promote bacterial swimming, whereas anthocyanidin cyanidin and flavonoid myricetin did not. No compounds that were tested inhibited bacterial swarming. Conclusion: Results of this study indicated that, although anthocyanidins may elicited an innate immune NO response from human cells, they do not cause an increase in ciliary beating and they may also cause a pathogenicity-enhancing effect in P. aeruginosa. Additional studies are necessary to understand how this would affect the use of anthocyanidins as therapeutics. This study emphasized the

  8. Fixed target hadron production measurements

    CERN Document Server

    Panman, J

    2009-01-01

    The knowledge of light hadron production cross-sections in proton-nucleus interactions is an important prerequisite to the analysis of a wide variety of experiments. One of the important limiting factors for the precision of accelerator based and atmospheric neutrino oscillation experiments is the uncertainty in the composition and spectrum of the neutrino flux. Cosmic-ray experiments detecting extensive air-showers can greatly improve their ability to interpret the data when precise hadron production spectra are available over a large range of energies. Dedicated hadron production experiments have been taking data recently and are now publishing their results. Other experiments have just started their data-taking and plan to supply measurements which can significantly extend the kinematic range in which data will be available. Early measurements at the LHC can extend this range to much higher energies than available up to now. Recent results will be shown and compared with hadronic production models. An outl...

  9. Measurement of radiative neutralino production

    CERN Document Server

    Bartels, Christoph; Langenfeld, Ulrich; List, Jenny

    2012-01-01

    We perform the first experimental study with full detector simulation for the radiative production of neutralinos at the linear collider, at sqrt{s} = 500 GeV and realistic beam polarizations. We consider all relevant backgrounds, like the Standard Model background from radiative neutrino production. The longitudinal polarized beams enhance the signal and simultaneously reduce the background, such that statistical errors are significantly reduced. We find that the photon spectrum from the signal process can be well isolated. The neutralino mass and the cross section can be measured at a few per-cent level, with the largest systematic uncertainties from the measurement of the beam polarization and the beam energy spectrum.

  10. Bacterial Cellulose Production by Gluconacetobacter sp. RKY5 in a Rotary Biofilm Contactor

    Science.gov (United States)

    Kim, Yong-Jun; Kim, Jin-Nam; Wee, Young-Jung; Park, Don-Hee; Ryu, Hwa-Won

    A rotary biofilm contactor (RBC) inoculated with Gluconacetobacter sp. RKY5 was used as a bioreactor for improved bacterial cellulose production. The optimal number of disk for bacterial cellulose production was found to be eight, at which bacterial cellulose and cell concentrations were 5.52 and 4.98 g/L. When the aeration rate was maintained at 1.25 vvm, bacterial cellulose and cell concentrations were maximized (5.67 and 5.25 g/L, respectively). The optimal rotation speed of impeller in RBC was 15 rpm. When the culture pH in RBC was not controlled during fermentation, the maximal amount of bacterial cellulose (5.53 g/L) and cells (4.91 g/L) was obtained. Under the optimized culture conditions, bacterial cellulose and cell concentrations in RBC reached to 6.17 and 5.58 g/L, respectively.

  11. Bacterial production and their role in the removal of dissolved organic matter from tributaries of drinking water reservoirs.

    Science.gov (United States)

    Kamjunke, Norbert; Oosterwoud, Marieke R; Herzsprung, Peter; Tittel, Jörg

    2016-04-01

    Enhanced concentrations of dissolved organic matter (DOM) in freshwaters are an increasing problem in drinking water reservoirs. In this study we investigated bacterial DOM degradation rates in the tributaries of the reservoirs and tested the hypotheses that (1) DOM degradation is high enough to decrease DOM loads to reservoirs considerably, (2) DOM degradation is affected by stream hydrology, and (3) phosphorus addition may stimulate bacterial DOM degradation. Bacterial biomass production, which was used as a measure of DOM degradation, was highest in summer, and was usually lower at upstream than at downstream sites. An important proportion of bacterial production was realized in epilithic biofilms. Production of planktonic and biofilm bacteria was related to water temperature. Planktonic production weakly correlated to DOM quality and to total phosphorus concentration. Addition of soluble reactive phosphorus did not stimulate bacterial DOM degradation. Overall, DOM was considerably degraded in summer at low discharge levels, whereas degradation was negligible during flood events (when DOM load in reservoirs was high). The ratio of DOM degradation to total DOM release was negatively related to discharge. On annual average, only 0.6-12% of total DOM released by the catchments was degraded within the tributaries.

  12. Chemical inhibition of bacterial protein tyrosine phosphatase suppresses capsule production.

    Science.gov (United States)

    Standish, Alistair J; Salim, Angela A; Zhang, Hua; Capon, Robert J; Morona, Renato

    2012-01-01

    Capsule polysaccharide is a major virulence factor for a wide range of bacterial pathogens, including Streptococcus pneumoniae. The biosynthesis of Wzy-dependent capsules in both gram-negative and -positive bacteria is regulated by a system involving a protein tyrosine phosphatase (PTP) and a protein tyrosine kinase. However, how the system functions is still controversial. In Streptococcus pneumoniae, a major human pathogen, the system is present in all but 2 of the 93 serotypes found to date. In order to study this regulation further, we performed a screen to find inhibitors of the phosphatase, CpsB. This led to the observation that a recently discovered marine sponge metabolite, fascioquinol E, inhibited CpsB phosphatase activity both in vitro and in vivo at concentrations that did not affect the growth of the bacteria. This inhibition resulted in decreased capsule synthesis in D39 and Type 1 S. pneumoniae. Furthermore, concentrations of Fascioquinol E that inhibited capsule also lead to increased attachment of pneumococci to a macrophage cell line, suggesting that this compound would inhibit the virulence of the pathogen. Interestingly, this compound also inhibited the phosphatase activity of the structurally unrelated gram-negative PTP, Wzb, which belongs to separate family of protein tyrosine phosphatases. Furthermore, incubation with Klebsiella pneumoniae, which contains a homologous phosphatase, resulted in decreased capsule synthesis. Taken together, these data provide evidence that PTPs are critical for Wzy-dependent capsule production across a spectrum of bacteria, and as such represents a valuable new molecular target for the development of anti-virulence antibacterials.

  13. Chemical inhibition of bacterial protein tyrosine phosphatase suppresses capsule production.

    Directory of Open Access Journals (Sweden)

    Alistair J Standish

    Full Text Available Capsule polysaccharide is a major virulence factor for a wide range of bacterial pathogens, including Streptococcus pneumoniae. The biosynthesis of Wzy-dependent capsules in both gram-negative and -positive bacteria is regulated by a system involving a protein tyrosine phosphatase (PTP and a protein tyrosine kinase. However, how the system functions is still controversial. In Streptococcus pneumoniae, a major human pathogen, the system is present in all but 2 of the 93 serotypes found to date. In order to study this regulation further, we performed a screen to find inhibitors of the phosphatase, CpsB. This led to the observation that a recently discovered marine sponge metabolite, fascioquinol E, inhibited CpsB phosphatase activity both in vitro and in vivo at concentrations that did not affect the growth of the bacteria. This inhibition resulted in decreased capsule synthesis in D39 and Type 1 S. pneumoniae. Furthermore, concentrations of Fascioquinol E that inhibited capsule also lead to increased attachment of pneumococci to a macrophage cell line, suggesting that this compound would inhibit the virulence of the pathogen. Interestingly, this compound also inhibited the phosphatase activity of the structurally unrelated gram-negative PTP, Wzb, which belongs to separate family of protein tyrosine phosphatases. Furthermore, incubation with Klebsiella pneumoniae, which contains a homologous phosphatase, resulted in decreased capsule synthesis. Taken together, these data provide evidence that PTPs are critical for Wzy-dependent capsule production across a spectrum of bacteria, and as such represents a valuable new molecular target for the development of anti-virulence antibacterials.

  14. The Niches of Bacterial Populations in Productive Waters : Examples from Coastal Waters and Four Eutrophic Lakes

    OpenAIRE

    Eiler, Alexander

    2006-01-01

    Recent research in microbial ecology has focused on how aquatic bacterial communities are assembled. Only a few of these studies follow a “Gleasonian” approach where the roles of single bacterial populations are in focus. In this thesis, novel molecular tools were used to describe the distribution and evolutionary relationships of microbes in productive aquatic environments. Many new phylogenetic groups of bacteria were identified, likely representing bacterial populations restricted to produ...

  15. Measurement of Ozone Production Sensor

    Directory of Open Access Journals (Sweden)

    M. Cazorla

    2010-05-01

    Full Text Available A new ambient air monitor, the Measurement of Ozone Production Sensor (MOPS, measures directly the rate of ozone production in the atmosphere. The sensor consists of two 11.3 L environmental chambers made of UV-transmitting Teflon film, a unit to convert NO2 to O3, and a modified ozone monitor. In the sample chamber, flowing ambient air is exposed to the sunlight so that ozone is produced just as it is in the atmosphere. In the second chamber, called the reference chamber, a UV-blocking film over the Teflon film prevents ozone formation but allows other processes to occur as they do in the sample chamber. The air flows that exit the two chambers are sampled by an ozone monitor operating in differential mode so that the difference between the two ozone signals, divided by the exposure time in the chambers, gives the ozone production rate. High-efficiency conversion of NO2 to O3 prior to detection in the ozone monitor accounts for differences in the NOx photostationary state that can occur in the two chambers. The MOPS measures the ozone production rate, but with the addition of NO to the sampled air flow, the MOPS can be used to study the sensitivity of ozone production to NO. Preliminary studies with the MOPS on the campus of the Pennsylvania State University show the potential of this new technique.

  16. Jet production measurements at CMS

    CERN Document Server

    Ganguly, Sanmay

    2013-01-01

    Jet production cross-section measurements are presented. The measurements are done with the data from Large Hadron Collider (LHC) proton-proton collisions, collected with the Compact Muon Solenoid (CMS) detector. The inclusive jet production measurements are carried out with data collected $\\rm \\sqrt{s} ~= ~7 ~TeV$ and $\\rm 8~TeV$ with total integrated luminosity ($\\mathcal{L}_{int}$) $\\rm 5.0~ fb^{-1}$ and $\\rm 10.71~ fb^{-1}$ respectively. The dijet production measurements are carried out with the $\\rm \\sqrt{s}~ =~ 7 ~TeV$ dataset. Jets are reconstructed with the anti-$k_T$ clustering algorithm with size parameter $R=0.7$. The measured cross sections are corrected for detector effects and compared to perturbative QCD predictions at NLO, corrected for NP factors, using various sets of PDF. The inclusive jet cross-section ratio of the jets reconstructed with the anti-$k_T$ (AK) algorithm and two radius parameter $\\rm R~=~0.5$ and $\\rm R~=~0.7$ are also presented. The data used is $\\rm \\sqrt{s}~ =~ 7 ~TeV$ CMS...

  17. A portable biosensor system for bacterial concentration measurements in cow's raw milk

    OpenAIRE

    Grossi, Marco; Lanzoni, Massimo; Pompei, Anna; Lazzarini, Roberto; Matteuzzi, Diego; Ricco, Bruno

    2011-01-01

    Bacterial detection is of primary importance in many fields, such as food and environmental monitoring. Measurements of bacterial concentration are traditionally carried out by means of the Standard Plate Count technique, a reliable method for microbial screening that, however, features long response time and is carried out by qualified personnel in microbiology laboratories. The impedance technique for bacterial concentration detection represents a method very competitive with Standard Plate...

  18. Chasing the Treasures of the Sea – Bacterial Marine Natural Products

    OpenAIRE

    Gulder, Tobias A.M.; Moore, Bradley S.

    2009-01-01

    Bacterial marine natural products are an important source of novel lead structures for drug discovery. The cytotoxic properties of many of these secondary metabolites are of particular interest for the development of new anti-cancer agents. Tremendous advances in marine molecular biology, genome sequencing, and bioinformatics have paved the way to fully exploit the biomedical potential of marine bacterial products. In addition, unique biosynthetic enzymes discovered from bacteria from the sea...

  19. Improvement of bacterial cellulose production by manipulating the metabolic pathways in which ethanol and sodium citrate involved.

    Science.gov (United States)

    Li, Yuanjing; Tian, Chunjie; Tian, Hua; Zhang, Jiliang; He, Xin; Ping, Wenxiang; Lei, Hong

    2012-12-01

    Nowadays, bacterial cellulose has played more and more important role as new biological material for food industry and medical and industrial products based on its unique properties. However, it is still a difficult task to improve the production of bacterial cellulose, especially a large number of byproducts are produced in the metabolic biosynthesis processes. To improve bacterial cellulose production, ethanol and sodium citrate are added into the medium during the fermentation, and the activities of key enzymes and concentration of extracellular metabolites are measured to assess the changes of the metabolic flux of the hexose monophosphate pathway (HMP), the Embden-Meyerhof-Parnas pathway (EMP), and the tricarboxylic acid cycle (TCA). Our results indicate that ethanol functions as energy source for ATP generation at the early stage of the fermentation in the HMP pathway and the supplementation of ethanol significantly reduces glycerol generation (a major byproduct). While in the EMP pathway, sodium citrate plays a key role, and its supplementation results in the byproducts (mainly acetic acid and pyruvic acid) entering the gluconeogenesis pathway for cellulose synthesis. Furthermore, by adding ethanol and sodium citrate, the main byproduct citric acid in the TCA cycle is also reduced significantly. It is concluded that bacterial cellulose production can be improved by increasing energy metabolism and reducing the formation of metabolic byproducts through the metabolic regulations of the bypasses.

  20. Production of bacterial cellulose and enzyme from waste fiber sludge

    OpenAIRE

    Cavka, Adnan; Guo, Xiang; Tang, Shui-Jia; Winestrand, Sandra; Jönsson, Leif J.; Hong, Feng

    2013-01-01

    Background: Bacterial cellulose (BC) is a highly crystalline and mechanically stable nanopolymer, which has excellent potential as a material in many novel applications, especially if it can be produced in large amounts from an inexpensive feedstock. Waste fiber sludge, a residue with little or no value, originates from pulp mills and lignocellulosic biorefineries. A high cellulose and low lignin content contributes to making the fiber sludge suitable for bioconversion, even without a thermoc...

  1. Proteomics as a Quality Control Tool of Pharmaceutical Probiotic Bacterial Lysate Products.

    Directory of Open Access Journals (Sweden)

    Günter Klein

    Full Text Available Probiotic bacteria have a wide range of applications in veterinary and human therapeutics. Inactivated probiotics are complex samples and quality control (QC should measure as many molecular features as possible. Capillary electrophoresis coupled to mass spectrometry (CE/MS has been used as a multidimensional and high throughput method for the identification and validation of biomarkers of disease in complex biological samples such as biofluids. In this study we evaluate the suitability of CE/MS to measure the consistency of different lots of the probiotic formulation Pro-Symbioflor which is a bacterial lysate of heat-inactivated Escherichia coli and Enterococcus faecalis. Over 5000 peptides were detected by CE/MS in 5 different lots of the bacterial lysate and in a sample of culture medium. 71 to 75% of the total peptide content was identical in all lots. This percentage increased to 87-89% when allowing the absence of a peptide in one of the 5 samples. These results, based on over 2000 peptides, suggest high similarity of the 5 different lots. Sequence analysis identified peptides of both E. coli and E. faecalis and peptides originating from the culture medium, thus confirming the presence of the strains in the formulation. Ontology analysis suggested that the majority of the peptides identified for E. coli originated from the cell membrane or the fimbrium, while peptides identified for E. faecalis were enriched for peptides originating from the cytoplasm. The bacterial lysate peptides as a whole are recognised as highly conserved molecular patterns by the innate immune system as microbe associated molecular pattern (MAMP. Sequence analysis also identified the presence of soybean, yeast and casein protein fragments that are part of the formulation of the culture medium. In conclusion CE/MS seems an appropriate QC tool to analyze complex biological products such as inactivated probiotic formulations and allows determining the similarity between

  2. Proteomics as a Quality Control Tool of Pharmaceutical Probiotic Bacterial Lysate Products.

    Science.gov (United States)

    Klein, Günter; Schanstra, Joost P; Hoffmann, Janosch; Mischak, Harald; Siwy, Justyna; Zimmermann, Kurt

    2013-01-01

    Probiotic bacteria have a wide range of applications in veterinary and human therapeutics. Inactivated probiotics are complex samples and quality control (QC) should measure as many molecular features as possible. Capillary electrophoresis coupled to mass spectrometry (CE/MS) has been used as a multidimensional and high throughput method for the identification and validation of biomarkers of disease in complex biological samples such as biofluids. In this study we evaluate the suitability of CE/MS to measure the consistency of different lots of the probiotic formulation Pro-Symbioflor which is a bacterial lysate of heat-inactivated Escherichia coli and Enterococcus faecalis. Over 5000 peptides were detected by CE/MS in 5 different lots of the bacterial lysate and in a sample of culture medium. 71 to 75% of the total peptide content was identical in all lots. This percentage increased to 87-89% when allowing the absence of a peptide in one of the 5 samples. These results, based on over 2000 peptides, suggest high similarity of the 5 different lots. Sequence analysis identified peptides of both E. coli and E. faecalis and peptides originating from the culture medium, thus confirming the presence of the strains in the formulation. Ontology analysis suggested that the majority of the peptides identified for E. coli originated from the cell membrane or the fimbrium, while peptides identified for E. faecalis were enriched for peptides originating from the cytoplasm. The bacterial lysate peptides as a whole are recognised as highly conserved molecular patterns by the innate immune system as microbe associated molecular pattern (MAMP). Sequence analysis also identified the presence of soybean, yeast and casein protein fragments that are part of the formulation of the culture medium. In conclusion CE/MS seems an appropriate QC tool to analyze complex biological products such as inactivated probiotic formulations and allows determining the similarity between lots. PMID

  3. The Study Of Metalworking Fluids Biodegradability By Indirect Measurement Of Bacterial Inoculum Respiration

    Directory of Open Access Journals (Sweden)

    Gerulová Kristína

    2015-06-01

    Full Text Available An apparatus for measuring biodegradability of metalworking fluids (MWFs was constructed according to (1, based on the Zahn-Wellens test which enables a continuous determination of CO2 production by the change in conductivity of absorption solution. Results obtained from the testing of 8 different MWFs by this modified method were compared to those obtained in standardized OECD 302 B. The comparison showed better description of bacterial inoculum activity in tested solution; lag phase was easy to indicate. Tested emulsion achieved the level of primary degradability 39.7 – 40.8 %, and semi-synthetics 19.1 – 43.5%. The samples of synthetics where the degradation level reached 43.9 - 58.6 % were identified as the most degradable metalworking fluids.

  4. The Study Of Metalworking Fluids Biodegradability By Indirect Measurement Of Bacterial Inoculum Respiration

    Science.gov (United States)

    Gerulová, Kristína; Tatarka, Ondrej; Štefko, Tomáš; Škulavík, Tomáš

    2015-06-01

    An apparatus for measuring biodegradability of metalworking fluids (MWFs) was constructed according to (1), based on the Zahn-Wellens test which enables a continuous determination of CO2 production by the change in conductivity of absorption solution. Results obtained from the testing of 8 different MWFs by this modified method were compared to those obtained in standardized OECD 302 B. The comparison showed better description of bacterial inoculum activity in tested solution; lag phase was easy to indicate. Tested emulsion achieved the level of primary degradability 39.7 - 40.8 %, and semi-synthetics 19.1 - 43.5%. The samples of synthetics where the degradation level reached 43.9 - 58.6 % were identified as the most degradable metalworking fluids.

  5. Dynamic properties of bacterial pili measured by optical tweezers

    CERN Document Server

    Fallman, Erik; Schedin, Staffan; Jass, Jana; Uhlin, Bernt Eric; Axner, Ove

    2014-01-01

    The ability of uropathogenic Escherichia coli (UPEC) to cause urinary tract infections is dependent on their ability to colonize the uroepithelium. Infecting bacteria ascend the urethra to the bladder and then kidneys by attaching to the uroepithelial cells via the differential expression of adhesins. P pili are associated with pyelonephritis, the more severe infection of the kidneys. In order to find means to treat pyelonephritis, it is therefore of interest to investigate the properties P pili. The mechanical behavior of individual P pili of uropathogenic Escherichia coli has recently been investigated using optical tweezers. P pili, whose main part constitutes the PapA rod, composed of ~1000 PapA subunits in a helical arrangement, are distributed over the bacterial surface and mediate adhesion to host cells. We have earlier studied P pili regarding its stretching/elongation properties where we have found and characterized three different elongation regions, of which one constitute an unfolding of the quate...

  6. Production of macroaggregates from dissolved exopolymeric substances (EPS) of bacterial and diatom origin

    Digital Repository Service at National Institute of Oceanography (India)

    Bhaskar, P.V.; Grossart, H.P.; Bhosle, N.B.; Simon, M.

    -1 1 Production of macroaggregates from dissolved exopolymeric substances (EPS) of bacterial and diatom origin P V Bhaskar1*, Hans-Peter Grossart2, 3, N B Bhosle1 and Meinhard Simon2. 1National Institute of Oceanography, Dona Paula, GOA- 403 004...-cycles [14]. Moreover, the composition and quality of these aggregates influence feeding and grazing rates of filter feeders [15], bacterial re-mineralization of organic matter, and POM-DOM conversion [16, 17, 18], thereby regulating the vertical flux...

  7. Anti-Biofilm Performance of Three Natural Products against Initial Bacterial Attachment

    Directory of Open Access Journals (Sweden)

    Keith R. Stokes

    2013-11-01

    Full Text Available Marine bacteria contribute significantly towards the fouling consortium, both directly (modern foul release coatings fail to prevent “slime” attachment and indirectly (biofilms often excrete chemical cues that attract macrofouling settlement. This study assessed the natural product anti-biofilm performance of an extract of the seaweed, Chondrus crispus, and two isolated compounds from terrestrial sources, (+-usnic acid and juglone, against two marine biofilm forming bacteria, Cobetia marina and Marinobacter hydrocarbonoclasticus. Bioassays were developed using quantitative imaging and fluorescent labelling to test the natural products over a range of concentrations against initial bacterial attachment. All natural products affected bacterial attachment; however, juglone demonstrated the best anti-biofilm performance against both bacterial species at a concentration range between 5–20 ppm. In addition, for the first time, a dose-dependent inhibition (hormetic response was observed for natural products against marine biofilm forming bacteria.

  8. Extracellular Lipase and Protease Production from a Model Drinking Water Bacterial Community Is Functionally Robust to Absence of Individual Members.

    Directory of Open Access Journals (Sweden)

    Graham G Willsey

    Full Text Available Bacteria secrete enzymes into the extracellular space to hydrolyze macromolecules into constituents that can be imported for microbial nutrition. In bacterial communities, these enzymes and their resultant products can be modeled as community property. Our goal was to investigate the impact of individual community member absence on the resulting community production of exoenzymes (extracellular enzymes involved in lipid and protein hydrolysis. Our model community contained nine bacteria isolated from the potable water system of the International Space Station. Bacteria were grown in static conditions individually, all together, or in all combinations of eight species and exoproduct production was measured by colorimetric or fluorometric reagents to assess short chain and long chain lipases, choline-specific phospholipases C, and proteases. The exoenzyme production of each species grown alone varied widely, however, the enzyme activity levels of the mixed communities were functionally robust to absence of any single species, with the exception of phospholipase C production in one community. For phospholipase C, absence of Chryseobacterium gleum led to increased choline-specific phospholipase C production, correlated with increased growth of Burkholderia cepacia and Sphingomonas sanguinis. Because each individual species produced different enzyme activity levels in isolation, we calculated an expected activity value for each bacterial mixture using input levels or known final composition. This analysis suggested that robustness of each exoenzyme activity is not solely mediated by community composition, but possibly influenced by bacterial communication, which is known to regulate such pathways in many bacteria. We conclude that in this simplified model of a drinking water bacterial community, community structure imposes constraints on production and/or secretion of exoenzymes to generate a level appropriate to exploit a given nutrient environment.

  9. Application of Bacterial Laccases for Sustainable Energy Production

    DEFF Research Database (Denmark)

    Lörcher, Samuel; Koschorreck, Katja; Shipovskov, Stepan;

    of laccase-based biocathodes in the biofuel cells and in the hybrid biobattery-type or photovoltaic power sources could essentially broaden their application, enabling extraction of energy from the sea water/water dissolved oxygen. Here we demonstrate up to 0.8 mW cm-2 extracted power densities and 1.5 month...... operation of domestic devices exploiting cheap and simple hybrid bio-batteries based on fungal laccases covalently attached to carbon materials. The main technological drawback of such systems is that the activity of fungal laccases is restricted to acidic media, which makes them inappropriate for operation...... laccases and electrodes, which resulted in highly efficient bioelectrocatalysis of O2 reduction. The hybrid biobattery exploiting the bacterial laccase biocathode is shown to efficiently operate in basic media....

  10. Isotopomers as a method for differentiating between bacterial and fungal production of nitrous oxide

    Science.gov (United States)

    Sutka, R. L.; Adams, G.; Ostrom, N.; Ostrom, P.

    2007-12-01

    In order to study the importance of fungi to nitrous oxide (N2O) production in the environment it is critical to have a non-intrusive method for differentiating between fungal and bacterial N2O production. Site preference (SP), the difference in d15N between the central and outer N atoms in N2O, has been used to differentiate between bacterial nitrification and denitrification. In this study we compare the SP, d15N and d18O of N2O produced by the two best-studied fungal denitrifiers, Fusarium oxysporum and Cylindrocarpon tonkinense, to data from our previous bacterial studies. Both d18O and SP values remained fairly constant during the course of nitrite reduction which likely reflects isotopic exchange with water in the case of d18O and conservative behavior in SP that has been observed previously (Sutka et al., 2006). We observed a wide range of fractionation factors for fungal denitrification, -74.7 to -6.6 ‰, and non-linear behavior indicating that fractionation was controlled by more than one step. We interpret the small degree of fractionation as reflecting fractionation during diffusion and the more negative values as being controlled by enzymatic fractionation. Data from this and our previous study of bacterial production (Sutka et al., 2006) reveals that N2O produced via nitrification by fungi can be differentiated from N2O produced by bacterial denitrification primarily on the basis of d18O. The site preference of N2O produced by F. oxysporum and C. tonkinense was 37.1 ± 2.5 ‰ and 36.9 ± 2.8 ‰, respectively. These results indicate that isotopomers can be used as a basis for differentiating bacterial and fungal denitrification. Our work further reveals the role that fungal and bacterial nitric oxide reductases have in determining site preference during N2O production.

  11. Bacterial production and microbial food web structure in a large arctic river and the coastal Arctic Ocean

    Science.gov (United States)

    Vallières, Catherine; Retamal, Leira; Ramlal, Patricia; Osburn, Christopher L.; Vincent, Warwick F.

    2008-12-01

    Globally significant quantities of organic carbon are stored in northern permafrost soils, but little is known about how this carbon is processed by microbial communities once it enters rivers and is transported to the coastal Arctic Ocean. As part of the Arctic River-Delta Experiment (ARDEX), we measured environmental and microbiological variables along a 300 km transect in the Mackenzie River and coastal Beaufort Sea, in July-August 2004. Surface bacterial concentrations averaged 6.7 × 10 5 cells mL - 1 with no significant differences between sampling zones. Picocyanobacteria were abundant in the river, and mostly observed as cell colonies. Their concentrations in the surface waters decreased across the salinity gradient, dropping from 51,000 (river) to 30 (sea) cells mL - 1 . There were accompanying shifts in protist community structure, from diatoms, cryptophytes, heterotrophic protists and chrysophytes in the river, to dinoflagellates, prymnesiophytes, chrysophytes, prasinophytes, diatoms and heterotrophic protists in the Beaufort Sea. Size-fractionated bacterial production, as measured by 3H-leucine uptake, varied from 76 to 416 ng C L - 1 h - 1 . The contribution of particle-attached bacteria (> 3 µm fraction) to total bacterial production decreased from > 90% at the Mackenzie River stations to importance of this particle-based fraction was inversely correlated with salinity and positively correlated with particulate organic carbon concentrations. Glucose enrichment experiments indicated that bacterial metabolism was carbon limited in the Mackenzie River but not in the coastal ocean. Prior exposure of water samples to full sunlight increased the biolability of dissolved organic carbon (DOC) in the Mackenzie River but decreased it in the Beaufort Sea. Estimated depth-integrated bacterial respiration rates in the Mackenzie River were higher than depth-integrated primary production rates, while at the marine stations bacterial respiration rates were near or

  12. Dynamic properties of bacterial pili measured by optical tweezers

    Science.gov (United States)

    Fallman, Erik G.; Andersson, Magnus J.; Schedin, Staffan S.; Jass, Jana; Uhlin, Bernt Eric; Axner, Ove

    2004-10-01

    The ability of uropathogenic Escherichia coli (UPEC) to cause urinary tract infections is dependent on their ability to colonize the uroepithelium. Infecting bacteria ascend the urethra to the bladder and then kidneys by attaching to the uroepithelial cells via the differential expression of adhesins. P pili are associated with pyelonephritis, the more severe infection of the kidneys. In order to find means to treat pyelonephritis, it is therefore of interest to investigate the properties P pili. The mechanical behavior of individual P pili of uropathogenic Escherichia coli has recently been investigated using optical tweezers. P pili, whose main part constitutes the PapA rod, composed of ~1000 PapA subunits in a helical arrangement, are distributed over the bacterial surface and mediate adhesion to host cells. We have earlier studied P pili regarding its stretching/elongation properties where we have found and characterized three different elongation regions, of which one constitute an unfolding of the quaternary (helical) structure of the PapA rod. It was shown that this unfolding takes place at an elongation independent force of 27 +/- 2 pN. We have also recently performed studies on its folding properties and shown that the unfolding/folding of the PapA rod is completely reversible. Here we present a study of the dynamical properties of the PapA rod. We show, among other things, that the unfolding force increases and that the folding force decreases with the speed of unfolding and folding respectively. Moreover, the PapA rod can be folded-unfolded a significant number of times without loosing its characteristics, a phenomenon that is believed to be important for the bacterium to keep close contact to the host tissue and consequently helps the bacterium to colonize the host tissue.

  13. Agricultural and Management Practices and Bacterial Contamination in Greenhouse versus Open Field Lettuce Production

    Directory of Open Access Journals (Sweden)

    Kevin Holvoet

    2014-12-01

    Full Text Available The aim of this study was to gain insight into potential differences in risk factors for microbial contamination in greenhouse versus open field lettuce production. Information was collected on sources, testing, and monitoring and if applicable, treatment of irrigation and harvest rinsing water. These data were combined with results of analysis on the levels of Escherichia coli as a fecal indicator organism and the presence of enteric bacterial pathogens on both lettuce crops and environmental samples. Enterohemorragic Escherichia coli (EHEC PCR signals (vt1 or vt2 positive and eae positive, Campylobacter spp., and Salmonella spp. isolates were more often obtained from irrigation water sampled from open field farms (21/45, 46.7% versus from greenhouse production (9/75, 12.0%. The open field production was shown to be more prone to fecal contamination as the number of lettuce samples and irrigation water with elevated E. coli was significantly higher. Farmers comply with generic guidelines on good agricultural practices available at the national level, but monitoring of microbial quality, and if applicable appropriateness of water treatment, or water used for irrigation or at harvest is restricted. These results indicate the need for further elaboration of specific guidelines and control measures for leafy greens with regard to microbial hazards.

  14. Agricultural and management practices and bacterial contamination in greenhouse versus open field lettuce production.

    Science.gov (United States)

    Holvoet, Kevin; Sampers, Imca; Seynnaeve, Marleen; Jacxsens, Liesbeth; Uyttendaele, Mieke

    2014-12-23

    The aim of this study was to gain insight into potential differences in risk factors for microbial contamination in greenhouse versus open field lettuce production. Information was collected on sources, testing, and monitoring and if applicable, treatment of irrigation and harvest rinsing water. These data were combined with results of analysis on the levels of Escherichia coli as a fecal indicator organism and the presence of enteric bacterial pathogens on both lettuce crops and environmental samples. Enterohemorragic Escherichia coli (EHEC) PCR signals (vt1 or vt2 positive and eae positive), Campylobacter spp., and Salmonella spp. isolates were more often obtained from irrigation water sampled from open field farms (21/45, 46.7%) versus from greenhouse production (9/75, 12.0%). The open field production was shown to be more prone to fecal contamination as the number of lettuce samples and irrigation water with elevated E. coli was significantly higher. Farmers comply with generic guidelines on good agricultural practices available at the national level, but monitoring of microbial quality, and if applicable appropriateness of water treatment, or water used for irrigation or at harvest is restricted. These results indicate the need for further elaboration of specific guidelines and control measures for leafy greens with regard to microbial hazards.

  15. Publishing productivity measures in ONS

    OpenAIRE

    Dawn Camus

    2007-01-01

    Comments on the joint publication launch of this edition of ELMR and The ONS Productivity Handbook.This July 2007 Economic & Labour Market Review (ELMR) is a special productivity edition and is published alongside The ONS Productivity Handbook: A Statistical Overview and Guide. Presenting all Officefor National Statistics (ONS) productivity estimates, sources, methods and analysis, this single volume will serve as a valuable reference on the subject. Articles printed in this edition of ELMR h...

  16. Inactivating effects of the lactoperoxidase system on bacterial lyases involved in oral malodour production.

    Science.gov (United States)

    Nakano, Manabu; Shin, Kouichirou; Wakabayashi, Hiroyuki; Yamauchi, Koji; Abe, Fumiaki; Hironaka, Shouji

    2015-10-01

    The main components of oral malodour have been identified as volatile sulfur compounds (VSCs), including hydrogen sulfide (H(2)S) and methyl mercaptan (CH(3)SH). The lactoperoxidase (LPO) system (consisting of LPO, glucose oxidase, glucose and thiocyanate) was previously shown to exhibit antimicrobial activities against some oral bacteria in vitro and suppressive effects on VSCs in mouth air in a clinical trial. Here, we examined the in vitro effects of the LPO system on the activities of the bacterial lyases involved in the production of VSCs by oral anaerobes. The exposure of crude bacterial extracts of Fusobacterium nucleatum and Porphyromonas gingivalis or purified methionine γ-lyase to the LPO system resulted in the inactivation of their lyase activities through l-cysteine and l-methionine, which was linked to the production of H(2)S and CH(3)SH, respectively. The exposure of living F. nucleatum and P. gingivalis cells to the LPO system resulted in the suppression of cell numbers and lyase activities. The inactivation of the crude bacterial extracts of F. nucleatum and purified methionine γ-lyase by the LPO system was partly recovered by the addition of DTT. Therefore, the LPO system may inactivate bacterial lyases including methionine γ-lyase by reacting with the free cysteine residues of lyases. These results suggested that the LPO system suppresses the production of VSCs not only through its antimicrobial effects, but also by its inactivating effects on the bacterial lyases of F. nucleatum and P. gingivalis.

  17. Measurement of Bacterial Bioluminescence Intensity and Spectrum: Current Physical Techniques and Principles.

    Science.gov (United States)

    Jia, Kun; Ionescu, Rodica Elena

    2016-01-01

    : Bioluminescence is light production by living organisms, which can be observed in numerous marine creatures and some terrestrial invertebrates. More specifically, bacterial bioluminescence is the "cold light" produced and emitted by bacterial cells, including both wild-type luminescent and genetically engineered bacteria. Because of the lively interplay of synthetic biology, microbiology, toxicology, and biophysics, different configurations of whole-cell biosensors based on bacterial bioluminescence have been designed and are widely used in different fields, such as ecotoxicology, food toxicity, and environmental pollution. This chapter first discusses the background of the bioluminescence phenomenon in terms of optical spectrum. Platforms for bacterial bioluminescence detection using various techniques are then introduced, such as a photomultiplier tube, charge-coupled device (CCD) camera, micro-electro-mechanical systems (MEMS), and complementary metal-oxide-semiconductor (CMOS) based integrated circuit. Furthermore, some typical biochemical methods to optimize the analytical performances of bacterial bioluminescent biosensors/assays are reviewed, followed by a presentation of author's recent work concerning the improved sensitivity of a bioluminescent assay for pesticides. Finally, bacterial bioluminescence as implemented in eukaryotic cells, bioluminescent imaging, and cancer cell therapies is discussed.

  18. Nitric oxide production in celomocytes of the earthworm Eisenia hortensis following bacterial challenge

    Directory of Open Access Journals (Sweden)

    SR Cook

    2015-02-01

    Full Text Available In this in vitro investigation, nitric oxide (NO production was induced within celomocytes of the earthworm Eisenia hortensis following microbial challenge. Celomocytes were pre-loaded with the fluorescent indicator 4-amino-5-methylamino-2’, 7’-difluorofluorescein diacetate (DAF-FM DA in order to detect the presence of intracellular nitric oxide subsequent to a 16 h incubation with chemically-fixed soil bacteria including Bacillus megaterium, Arthrobacter globiformis, Pseudomonas stutzeri, and Azotobacter chroococcum at a range of multiplicities of infection (MOIs. Flow cytometric analysis measuring increases in relative fluorescence intensity (RFI, which is directly proportional to the amount of intracellular NO produced, permitted determination of statistical significance (p < 0.05 of exposed celomocytes compared to baseline controls. Significant increases in NO were detected reproducibly in celomocytes treated with all bacterial species used. The most prominent results were observed after exposure to Gram positive B. megaterium and A. globiformis where 100 % of earthworms tested exhibited statistically significant increases of RFI at MOIs of 100:1 and 500:1, respectively. Furthermore, significant decreases in NO production in bacteria-stimulated earthworm celomocytes incubated with the NOS inhibitor aminoguanidine hydrochloride were observed. These results demonstrate microbial induction of NO synthesis in earthworms and provide evidence of an antimicrobial role of NO in the innate immune system.

  19. Can procalcitonin measurement help in differentiating between bacterial infection and other kinds of inflammatory processes?

    Science.gov (United States)

    Delevaux, I; Andre, M; Colombier, M; Albuisson, E; Meylheuc, F; Begue, R; Piette, J; Aumaitre, O

    2003-01-01

    Objective: To study the levels of procalcitonin (PCT) in various inflammatory states seen in an internal medicine department and to evaluate the possible discriminative role of PCT in differentiating bacterial infection from other inflammatory processes. Methods: PCT, C reactive protein (CRP), and white blood cell count (WBC) were measured in patients admitted to the department for fever or biological inflammatory syndrome, or both. The serum of 173 consecutive patients was analysed according to the aetiological diagnosis. The patients were divided into two groups: group I (n=60) with documented bacterial or fungal infection; group II (n=113) with abacterial inflammatory disease. Results: PCT levels were >0.5 ng/ml in 39/60 (65%) patients in group I. In group II, three patients with a viral infection had slightly increased PCT levels (0.7, 0.8, and 1.1 ng/ml) as did two others, one with crystal arthritis and the other with vasculitis (0.7 ng/ml in both cases). All other patients in group II had PCT levels 0.5 ng/ml was taken as the marker of bacterial infection (sensitivity 65%, specificity 96%). PCT values were more discriminative than WBC and CRP in distinguishing a bacterial infection from another inflammatory process. Conclusion: PCT levels only rose significantly during bacterial infections. In this study PCT levels >1.2 ng/ml were always evidence of bacterial infection and the cue for starting antibiotic treatment. PMID:12634233

  20. Side effects of extra tRNA supplied in a typical bacterial protein production scenario

    DEFF Research Database (Denmark)

    Søgaard, Karina Marie; Nørholm, Morten H. H.

    2016-01-01

    Recombinant protein production is at the core of biotechnology and numerous molecular tools and bacterial strains have been developed to make the process more efficient. One commonly used generic solution is to supply extra copies of low-abundance tRNAs to compensate for the presence of complemen...

  1. Oxygen-­dependent regulation of bacterial lipid production

    Energy Technology Data Exchange (ETDEWEB)

    Lemmer, Kimberly C.; Dohnalkova, Alice; Noguera, Daniel R.; Donohue, Timothy J.

    2015-05-12

    Understanding the mechanisms of lipid accumulation in microorganisms is important for several reasons. In addition to providing insight into assembly of biological membranes, lipid accumulation has important applications in the production of renewable fuels and chemicals. The photosynthetic bacterium Rhodobacter sphaeroides is an attractive organism to study lipid accumulation, as it has the somewhat unique ability to increase membrane production at low O₂ tensions. Under these conditions, R. sphaeroides develops invaginations of the cytoplasmic membrane to increase its membrane surface area for housing of the membrane-bound components of its photosynthetic apparatus. Here we use fatty acid levels as a reporter of membrane lipid content. We show that, under low-O₂ and anaerobic conditions, the total fatty acid content per cell increases 3-fold. We also find that the increases in the amount of fatty acid and photosynthetic pigment per cell are correlated as O₂ tensions or light intensity are changed. To ask if lipid and pigment accumulation were genetically separable, we analyzed strains with mutations in known photosynthetic regulatory pathways. While a strain lacking AppA failed to induce photosynthetic pigment-protein complex accumulation, it increased fatty acid content under low O2 conditions. We also found that an intact PrrBA pathway is required for low O2-induced fatty acid accumulation. Our findings suggest a previously unknown role of R. sphaeroides transcriptional regulators in increasing fatty acid and phospholipid accumulation in response to decreased O₂ tension.

  2. Polysaccharides enriched in rare sugars: bacterial sources, production and applications

    Directory of Open Access Journals (Sweden)

    Christophe eRoca

    2015-04-01

    Full Text Available Microbial extracellular polysaccharides (EPS, produced by a wide range of bacteria, are high molecular weight biopolymers, presenting an extreme diversity in terms of chemical structure and composition. They may be used in many applications, depending on their chemical and physical properties. A rather unexplored aspect is the presence of rare sugars in the composition of some EPS. Rare sugars, such as rhamnose or fucose, may provide EPS with additional biological properties compared to those composed of more common sugar monomers.This review gives a brief overview of these specific EPS and their producing bacteria. Cultivation conditions are summarized, demonstrating their impact on the EPS composition, together with downstream processing. Finally, their use in different areas, including cosmetics, food products, pharmaceuticals and biomedical applications, are discussed.

  3. Variable effects of dispersal on productivity of bacterial communities due to changes in functional trait composition.

    Directory of Open Access Journals (Sweden)

    Ina Severin

    Full Text Available Previous studies have shown variable relationships between dispersal rate and ecosystem functioning, but the reasons for and mechanisms behind variable dispersal rate-functioning patterns are currently unknown. In this study we used six bacterial lake water communities in a laboratory experiment in order to investigate how dispersal among communities influences community productivity by evaluating three different mechanisms: 1 changes in taxonomic diversity, 2 changes in phylogenetic diversity or 3 changes in the composition of functional traits. The experiment was conducted in two phases; (A a dialysis bag experiment where the dispersal rate among six communities was manipulated and the subsequent change in bacterial diversity and growth rate was recorded, and (B a regrowth experiment where we manipulated available resources to study how well a taxon grows on certain organic carbon resources, i.e. their functional traits. From experiment (B we could thus estimate changes in functional traits in communities in experiment (A. Bacterial production was affected by dispersal, but not consistently among lakes. Neither change in taxonomic or phylogenetic diversity with dispersal could explain the observed dispersal-productivity relationships. Instead, changes in trait composition with dispersal, especially the communities' ability to use p-coumaric acid, an aromatic compound, could explain the observed dispersal-productivity relationships. Changes in this trait caused by dispersal seemed especially important for bacterial productivity in waters with a high aromaticity of the organic matter pool. We conclude that the effect of dispersal on bacterial communities can affect ecosystem functioning in different ways, through changes in functional key-traits which are important for the local environment.

  4. Effects of aromatic compounds on the production of bacterial nanocellulose by Gluconacetobacter xylinus

    OpenAIRE

    Zhang, Shuo; Winestrand, Sandra; Guo, Xiang; Chen, Lin; Hong, Feng; Jönsson, Leif

    2014-01-01

    Background: Bacterial cellulose (BC) is a polymeric nanostructured fibrillar network produced by certain microorganisms, principally Gluconacetobacter xylinus. BC has a great potential of application in many fields. Lignocellulosic biomass has been investigated as a cost-effective feedstock for BC production through pretreatment and hydrolysis. It is well known that detoxification of lignocellulosic hydrolysates may be required to achieve efficient production of BC. Recent results suggest tha...

  5. Production of Metabolites as Bacterial Responses to the Marine Environment

    Directory of Open Access Journals (Sweden)

    Pedro Fernandes

    2010-03-01

    Full Text Available Bacteria in marine environments are often under extreme conditions of e.g., pressure, temperature, salinity, and depletion of micronutrients, with survival and proliferation often depending on the ability to produce biologically active compounds. Some marine bacteria produce biosurfactants, which help to transport hydrophobic low water soluble substrates by increasing their bioavailability. However, other functions related to heavy metal binding, quorum sensing and biofilm formation have been described. In the case of metal ions, bacteria developed a strategy involving the release of binding agents to increase their bioavailability. In the particular case of the Fe3+ ion, which is almost insoluble in water, bacteria secrete siderophores that form soluble complexes with the ion, allowing the cells to uptake the iron required for cell functioning. Adaptive changes in the lipid composition of marine bacteria have been observed in response to environmental variations in pressure, temperature and salinity. Some fatty acids, including docosahexaenoic and eicosapentaenoic acids, have only been reported in prokaryotes in deep-sea bacteria. Cell membrane permeability can also be adapted to extreme environmental conditions by the production of hopanoids, which are pentacyclic triterpenoids that have a function similar to cholesterol in eukaryotes. Bacteria can also produce molecules that prevent the attachment, growth and/or survival of challenging organisms in competitive environments. The production of these compounds is particularly important in surface attached strains and in those in biofilms. The wide array of compounds produced by marine bacteria as an adaptive response to demanding conditions makes them suitable candidates for screening of compounds with commercially interesting biological functions. Biosurfactants produced by marine bacteria may be helpful to increase mass transfer in different industrial processes and in the bioremediation of

  6. 30 CFR 250.1633 - Production measurement.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Production measurement. 250.1633 Section 250... SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Sulphur Operations § 250.1633 Production measurement. (a) General. Measurement equipment and security procedures shall be designed, installed, used, maintained,...

  7. Ecosystem productivity is associated with bacterial phylogenetic distance in surface marine waters.

    Science.gov (United States)

    Galand, Pierre E; Salter, Ian; Kalenitchenko, Dimitri

    2015-12-01

    Understanding the link between community diversity and ecosystem function is a fundamental aspect of ecology. Systematic losses in biodiversity are widely acknowledged but the impact this may exert on ecosystem functioning remains ambiguous. There is growing evidence of a positive relationship between species richness and ecosystem productivity for terrestrial macro-organisms, but similar links for marine micro-organisms, which help drive global climate, are unclear. Community manipulation experiments show both positive and negative relationships for microbes. These previous studies rely, however, on artificial communities and any links between the full diversity of active bacterial communities in the environment, their phylogenetic relatedness and ecosystem function remain hitherto unexplored. Here, we test the hypothesis that productivity is associated with diversity in the metabolically active fraction of microbial communities. We show in natural assemblages of active bacteria that communities containing more distantly related members were associated with higher bacterial production. The positive phylogenetic diversity-productivity relationship was independent of community diversity calculated as the Shannon index. From our long-term (7-year) survey of surface marine bacterial communities, we also found that similarly, productive communities had greater phylogenetic similarity to each other, further suggesting that the traits of active bacteria are an important predictor of ecosystem productivity. Our findings demonstrate that the evolutionary history of the active fraction of a microbial community is critical for understanding their role in ecosystem functioning. PMID:26289961

  8. Screening of Bacterial Strains for Polygalacturonase Activity: Its Production by Bacillus sphaericus (MTCC 7542

    Directory of Open Access Journals (Sweden)

    Ranveer Singh Jayani

    2010-01-01

    Full Text Available At present almost all the pectinolytic enzymes used for industrial applications are produced by fungi. There are a few reports of pectinase production by bacterial strains. Therefore, in the present study, seventy-four bacterial strains, isolated from soil and rotten vegetable samples, were screened for polygalacturonase production. The strain PG-31, which gave maximum activity, was identified as Bacillus sphaericus (MTCC 7542. Maximal quantities of polygalacturonase were produced when a 16-hours-old inoculum was used at 7.5% (v/v in production medium and incubated in shaking conditions (160 rpm for 72 hours. The optimal temperature and pH for bacterial growth and polygalacturonase production were found to be 30∘C and 6.8, respectively. Maximum enzyme production resulted when citrus pectin was used as the carbon source at a concentration of 1.25% (w/v, whereas other carbon sources led to a decrease (30%–70% in enzyme production. Casein hydrolysate and yeast extract used together as organic nitrogen source gave best results, and ammonium chloride was found to be the most suitable inorganic nitrogen source. The supplementation of media with 0.9% (w/v D-galacturonic acid led to a 23% increase in activity. Bacillus sphaericus, a bacterium isolated from soil, produced good amount of polygalacturonase activity at neutral pH; hence, it would be potentially useful to increase the yield of banana, grape, or apple juice.

  9. Enhanced production of bacterial cellulose by using Gluconacetobacter hansenii NCIM 2529 strain under shaking conditions.

    Science.gov (United States)

    Mohite, Bhavna V; Salunke, Bipinchandra K; Patil, Satish V

    2013-03-01

    Bacterial cellulose (BC), a biopolymer, due to its unique properties is valuable for production of vital products in food, textile, medicine, and agriculture. In the present study, the optimal fermentation conditions for enhanced BC production by Gluconacetobacter hansenii NCIM 2529 were investigated under shaking conditions. The investigation on media components and culture parameters revealed that 2 % (w/v) sucrose as carbon source, 0.5 % (w/v) potassium nitrate as nitrogen source, 0.4 % (w/v) disodium phosphate as phosphate source, 0.04 % (w/v) magnesium sulfate, and 0.8 % (w/v) calcium chloride as trace elements, pH5.0, temperature 25 °C, and agitation speed 170 rpm with 6 days of fermentation period are optimal for maximum BC production. Production of BC using optimized media components and culture parameters was 1.66 times higher (5.0 g/l) than initial non optimized media (3.0 g/l). Fourier transform infrared spectroscopy spectrum and comparison with the available literature suggests that the produced component by G. hansenii in the present study is pure bacterial cellulose. The specific action of cellulase out of the investigated hydrolytic enzymes (cellulase, amylase, and protease) further confirmed purity of the produced BC. These findings give insight into conditions necessary for enhanced production of bacterial cellulose, which can be used for a variety of applications.

  10. Characterization of Bacterial Communities in Selected Smokeless Tobacco Products Using 16S rDNA Analysis.

    Directory of Open Access Journals (Sweden)

    Robert E Tyx

    Full Text Available The bacterial communities present in smokeless tobacco (ST products have not previously reported. In this study, we used Next Generation Sequencing to study the bacteria present in U.S.-made dry snuff, moist snuff and Sudanese toombak. Sample diversity and taxonomic abundances were investigated in these products. A total of 33 bacterial families from four phyla, Actinobacteria, Firmicutes, Proteobacteria and Bacteroidetes, were identified. U.S.-produced dry snuff products contained a diverse distribution of all four phyla. Moist snuff products were dominated by Firmicutes. Toombak samples contained mainly Actinobacteria and Firmicutes (Aerococcaceae, Enterococcaceae, and Staphylococcaceae. The program PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States was used to impute the prevalence of genes encoding selected bacterial toxins, antibiotic resistance genes and other pro-inflammatory molecules. PICRUSt also predicted the presence of specific nitrate reductase genes, whose products can contribute to the formation of carcinogenic nitrosamines. Characterization of microbial community abundances and their associated genomes gives us an indication of the presence or absence of pathways of interest and can be used as a foundation for further investigation into the unique microbiological and chemical environments of smokeless tobacco products.

  11. Characterization of Bacterial Communities in Selected Smokeless Tobacco Products Using 16S rDNA Analysis.

    Science.gov (United States)

    Tyx, Robert E; Stanfill, Stephen B; Keong, Lisa M; Rivera, Angel J; Satten, Glen A; Watson, Clifford H

    2016-01-01

    The bacterial communities present in smokeless tobacco (ST) products have not previously reported. In this study, we used Next Generation Sequencing to study the bacteria present in U.S.-made dry snuff, moist snuff and Sudanese toombak. Sample diversity and taxonomic abundances were investigated in these products. A total of 33 bacterial families from four phyla, Actinobacteria, Firmicutes, Proteobacteria and Bacteroidetes, were identified. U.S.-produced dry snuff products contained a diverse distribution of all four phyla. Moist snuff products were dominated by Firmicutes. Toombak samples contained mainly Actinobacteria and Firmicutes (Aerococcaceae, Enterococcaceae, and Staphylococcaceae). The program PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) was used to impute the prevalence of genes encoding selected bacterial toxins, antibiotic resistance genes and other pro-inflammatory molecules. PICRUSt also predicted the presence of specific nitrate reductase genes, whose products can contribute to the formation of carcinogenic nitrosamines. Characterization of microbial community abundances and their associated genomes gives us an indication of the presence or absence of pathways of interest and can be used as a foundation for further investigation into the unique microbiological and chemical environments of smokeless tobacco products.

  12. Production and characterization of bacterial cellulose by Leifsonia sp. CBNU-EW3 isolated from the earthworm, Eisenia fetida

    Science.gov (United States)

    A total of five bacterial strains were isolated from earthworm, Eisenia fetida and examined for bacterial cellulose (BC) production in Hestrin–Schramm medium (HS). Among the five strains tested, CBNU-EW3 exhibited excellent BC production and was identified as Leifsonia sp. by 16S rDNA sequence analy...

  13. Use of Natural Antimicrobial Peptides and Bacterial Biopolymers for Cultured Pearl Production.

    Science.gov (United States)

    Simon-Colin, Christelle; Gueguen, Yannick; Bachere, Evelyne; Kouzayha, Achraf; Saulnier, Denis; Gayet, Nicolas; Guezennec, Jean

    2015-06-01

    Cultured pearls are the product of grafting and rearing of Pinctada margaritifera pearl oysters in their natural environment. Nucleus rejections and oyster mortality appear to result from bacterial infections or from an inappropriate grafting practice. To reduce the impact of bacterial infections, synthetic antibiotics have been applied during the grafting practice. However, the use of such antibiotics presents a number of problems associated with their incomplete biodegradability, limited efficacy in some cases, and an increased risk of selecting for antimicrobial resistant bacteria. We investigated the application of a marine antimicrobial peptide, tachyplesin, which is present in the Japanese horseshoe crab Tachypleus tridentatus, in combination with two marine bacterial exopolymers as alternative treatment agents. In field studies, the combination treatment resulted in a significant reduction in graft failures vs. untreated controls. The combination of tachyplesin (73 mg/L) with two bacterial exopolysaccharides (0.5% w/w) acting as filming agents, reduces graft-associated bacterial contamination. The survival data were similar to that reported for antibiotic treatments. These data suggest that non-antibiotic treatments of pearl oysters may provide an effective means of improving oyster survival following grafting procedures.

  14. Use of Natural Antimicrobial Peptides and Bacterial Biopolymers for Cultured Pearl Production

    Science.gov (United States)

    Simon-Colin, Christelle; Gueguen, Yannick; Bachere, Evelyne; Kouzayha, Achraf; Saulnier, Denis; Gayet, Nicolas; Guezennec, Jean

    2015-01-01

    Cultured pearls are the product of grafting and rearing of Pinctada margaritifera pearl oysters in their natural environment. Nucleus rejections and oyster mortality appear to result from bacterial infections or from an inappropriate grafting practice. To reduce the impact of bacterial infections, synthetic antibiotics have been applied during the grafting practice. However, the use of such antibiotics presents a number of problems associated with their incomplete biodegradability, limited efficacy in some cases, and an increased risk of selecting for antimicrobial resistant bacteria. We investigated the application of a marine antimicrobial peptide, tachyplesin, which is present in the Japanese horseshoe crab Tachypleus tridentatus, in combination with two marine bacterial exopolymers as alternative treatment agents. In field studies, the combination treatment resulted in a significant reduction in graft failures vs. untreated controls. The combination of tachyplesin (73 mg/L) with two bacterial exopolysaccharides (0.5% w/w) acting as filming agents, reduces graft-associated bacterial contamination. The survival data were similar to that reported for antibiotic treatments. These data suggest that non-antibiotic treatments of pearl oysters may provide an effective means of improving oyster survival following grafting procedures. PMID:26110895

  15. Use of Natural Antimicrobial Peptides and Bacterial Biopolymers for Cultured Pearl Production

    Directory of Open Access Journals (Sweden)

    Christelle Simon-Colin

    2015-06-01

    Full Text Available Cultured pearls are the product of grafting and rearing of Pinctada margaritifera pearl oysters in their natural environment. Nucleus rejections and oyster mortality appear to result from bacterial infections or from an inappropriate grafting practice. To reduce the impact of bacterial infections, synthetic antibiotics have been applied during the grafting practice. However, the use of such antibiotics presents a number of problems associated with their incomplete biodegradability, limited efficacy in some cases, and an increased risk of selecting for antimicrobial resistant bacteria. We investigated the application of a marine antimicrobial peptide, tachyplesin, which is present in the Japanese horseshoe crab Tachypleus tridentatus, in combination with two marine bacterial exopolymers as alternative treatment agents. In field studies, the combination treatment resulted in a significant reduction in graft failures vs. untreated controls. The combination of tachyplesin (73 mg/L with two bacterial exopolysaccharides (0.5% w/w acting as filming agents, reduces graft-associated bacterial contamination. The survival data were similar to that reported for antibiotic treatments. These data suggest that non-antibiotic treatments of pearl oysters may provide an effective means of improving oyster survival following grafting procedures.

  16. Productivity Measurement Of Technical Institute

    Directory of Open Access Journals (Sweden)

    Miss.Pooja Yadav

    2015-05-01

    Full Text Available Abstract The increasing concern over globalization between other things has made the achievement of lifetime skills vital for all classes of people. Achievement of such skills can be developed from technical education programs in the advance of any nation. Skill gaining provides knowledge and inculcates the approaches that are essential for arrival and progress into an occupation. When skills are developed in any occupation it will provide and improve the standard of living with the cover beside poverty thereby behind national development. This paper observes sampling distribution and moving average concept that how technical education can generate the required skills the significance of skill acquisition its roles benefits and sustainability in national development. It also mentions among others that government should look into and improve productivity that can encourage skill achievement for the youths. The solutions are divided the sampling box into few group before stacking up workstation and use table and some other wood product. Cost reduction for each solution was intended and the solution with highest cost decrease is chosen to increase the productivity of the college.

  17. MEASURING PRODUCTIVITY OF SOFTWARE DEVELOPMENT TEAMS

    Directory of Open Access Journals (Sweden)

    Goparaju Purna Sudhakar

    2012-02-01

    Full Text Available This paper gives an exhaustive literature review of the techniques and models available tomeasure the productivity of software development teams. Definition of productivity, measuringindividual programmer’s productivity, and measuring software development team productivity arediscussed. Based on the literature review it was found that software productivity measurement canbe done using SLOC (Source Lines of Code, function points, use case points, object points, andfeature points. Secondary research findings indicate that the team size, response time, taskcomplexity, team climate and team cohesion have an impact on software development teamproductivity. List of factors affecting the software development team productivity are studied andreviewed.

  18. Recombinant production of bacterial toxins and their derivatives in the methylotrophic yeast Pichia pastoris

    Directory of Open Access Journals (Sweden)

    Gurkan Cemal

    2005-12-01

    Full Text Available Abstract The methylotrophic yeast Pichia pastoris is a popular heterologous expression host for the recombinant production of a variety of prokaryotic and eukaryotic proteins. The rapid emergence of P. pastoris as a robust heterologous expression host was facilitated by the ease with which it can be manipulated and propagated, which is comparable to that of Escherichia coli and Saccharomyces cerevisiae. P. pastoris offers further advantages such as the tightly-regulated alcohol oxidase promoter that is particularly suitable for heterologous expression of foreign genes. While recombinant production of bacterial toxins and their derivatives is highly desirable, attempts at their heterologous expression using the traditional E. coli expression system can be problematic due to the formation of inclusion bodies that often severely limit the final yields of biologically active products. However, recent literature now suggests that P. pastoris may be an attractive alternative host for the heterologous production of bacterial toxins, such as those from the genera Bacillus, Clostridium, and Corynebacterium, as well as their more complex derivatives. Here, we review the recombinant production of bacterial toxins and their derivatives in P. pastoris with special emphasis on their potential clinical applications. Considering that de novo design and construction of synthetic toxin genes have often been necessary to achieve optimal heterologous expression in P. pastoris, we also present general guidelines to this end based on our experience with the P. pastoris expression of the Bacillus thuringiensis Cyt2Aa1 toxin.

  19. Heterotrophic bacterial production and metabolic balance during the VAHINE mesocosm experiment in the New Caledonia lagoon

    Science.gov (United States)

    Van Wambeke, F.; Pfreundt, U.; Barani, A.; Berthelot, H.; Moutin, T.; Rodier, M.; Hess, W. R.; Bonnet, S.

    2015-12-01

    N2 fixation fuels ~ 50 % of new primary production in the oligotrophic South Pacific Ocean. The VAHINE mesocosm experiment designed to track the fate of diazotroph derived nitrogen (DDN) in the New Caledonia lagoon. Here, we examined the temporal dynamics of heterotrophic bacterial production during this experiment. Three replicate large-volume (~ 50 m3) mesocosms were deployed and were intentionally fertilized with dissolved inorganic phosphorus (DIP) to stimulate N2 fixation. We specifically examined relationships between N2 fixation rates and primary production, determined bacterial growth efficiency and established carbon budgets of the system from the DIP fertilization to the end of the experiment (days 5-23). Heterotrophic bacterioplankton production (BP) and alkaline phosphatase activity (APA) were statistically higher during the second phase of the experiment (P2: days 15-23), when chlorophyll biomass started to increase compared to the first phase (P1: days 5-14). Among autotrophs, Synechococcus abundances increased during P2, possibly related to its capacity to assimilate leucine and to produce alkaline phosphatase. Bacterial growth efficiency based on the carbon budget was notably higher than generally cited for oligotrophic environments (27-43 %), possibly due to a high representation of proteorhodopsin-containing organisms within the picoplanctonic community. The carbon budget showed that the main fate of gross primary production (particulate + dissolved) was respiration (67 %), and export through sedimentation (17 %). BP was highly correlated with particulate primary production and chlorophyll biomass during both phases of the experiment but slightly correlated, and only during P2 phase, with N2 fixation rates. Our results suggest that most of the DDN reached the heterotrophic bacterial community through indirect processes, like mortality, lysis and grazing.

  20. TLR2-induced IL-10 production impairs neutrophil recruitment to infected tissues during neonatal bacterial sepsis.

    Science.gov (United States)

    Andrade, Elva B; Alves, Joana; Madureira, Pedro; Oliveira, Liliana; Ribeiro, Adília; Cordeiro-da-Silva, Anabela; Correia-Neves, Margarida; Trieu-Cuot, Patrick; Ferreira, Paula

    2013-11-01

    Sepsis is the third most common cause of neonatal death, with Group B Streptococcus (GBS) being the leading bacterial agent. The pathogenesis of neonatal septicemia is still unsolved. We described previously that host susceptibility to GBS infection is due to early IL-10 production. In this study, we investigated whether triggering TLR2 to produce IL-10 is a risk factor for neonatal bacterial sepsis. We observed that, in contrast to wild-type (WT) pups, neonatal TLR2-deficient mice were resistant to GBS-induced sepsis. Moreover, if IL-10 signaling were blocked in WT mice, they also were resistant to sepsis. This increased survival rate was due to an efficient recruitment of neutrophils to infected tissues that leads to bacterial clearance, thus preventing the development of sepsis. To confirm that IL-10 produced through TLR2 activation prevents neutrophil recruitment, WT pups were treated with the TLR2 agonist Pam3CSK4 prior to nebulization with the neutrophil chemotactic agent LTB4. Neutrophil recruitment into the neonatal lungs was inhibited in pups treated with Pam3CSK4. However, the migration was restored in Pam3CSK4-treated pups when IL-10 signaling was blocked (either by anti-IL-10R mAb treatment or by using IL-10-deficient mice). Our findings highlight that TLR2-induced IL-10 production is a key event in neonatal susceptibility to bacterial sepsis. PMID:24078699

  1. Effects of the sea urchin Echinocardium cordatum on bacterial production and carbon flow in experimental benthic systems under increasing organic loading

    Science.gov (United States)

    Osinga, Ronald; Kop, Arjen J.; Malschaert, Johannes F. P.; Van Duyl, Fleur C.

    1997-05-01

    Effects of the sea urchin Echinocardium cordatum on benthic bacterial production were studied in marine sediment boxcosms, to which different amounts of organic matter (30, 60 and 90 g C m -2) were added. Bacterial production was estimated from incorporation rates of 3H-labelled leucine. The distribution of organic carbon in the boxcosm sediments was monitored. Measurements were done over a period of 27 days after the introduction of organic matter. Non-enriched boxcosms were used as controls. In macrobenthos-free boxcosms, the bacterial response to organic-matter additions mainly took place in the organic-matter layer on the sediment surface and in the upper 3 mm of the sediment. In the presence of E. cordatum, more organic matter was transported into the sediment, and the bacterial production rates in deeper sediment layers were higher. Increasing the organic loading did not further enhance these rates. It is concluded that E. cordatum stimulates bacterial production in deeper sediment layers by increasing the transport of organic matter into the sediment and perhaps also by promoting its degradation. At an increasing load with organic matter, the relative importance of the effects of E. cordatum decreases.

  2. Bacterial production and transformation of dissolved neutral sugars and amino acids in seawater

    Directory of Open Access Journals (Sweden)

    L. Jørgensen

    2014-04-01

    Full Text Available Dissolved organic matter (DOM in the ocean consists of a heterogeneous mixture of molecules, most of which are of unknown origin. Neutral sugars and amino acids are among the few recognizable biomolecules in DOM, and the molecular composition of these biomolecules is shaped primarily by biological production and degradation processes. This study provides insight into the bioavailability of biomolecules as well as the chemical composition of DOM produced by bacteria. The molecular compositions of neutral sugars and amino acids were investigated in DOM produced by bacteria and in DOM remaining after long-term bacterial degradation. Results from bioassay incubations (32 days with natural and artificial seawater, indicate that the molecular compositions following bacterial degradation are not strongly influenced by the initial substrate or bacterial community. The molecular composition of neutral sugars released by bacteria was characterized by a high glucose content (47 mol% and heterogeneous contributions from other neutral sugars (3–14 mol%. DOM remaining after bacterial degradation was characterized by a high galactose content (33 mol%, followed by glucose (22 mol% and the remaining neutral sugars (7–11 mol%. The ratio of D-amino acids to L-amino acids increased during the experiments as a response to bacterial degradation, and after 32 days the D/L ratios of aspartic acid, glutamic acid, serine and alanine reached around 0.79, 0.32, 0.30 and 0.51 in all treatments, respectively. The striking similarity in neutral sugar and amino acid compositions between natural and artificial seawater samples, suggests that the microbial carbon pump also applies for neutral sugars and amino acids and that bacterially-produced biomolecules persist for long periods in the ocean.

  3. Alternative indicators for measuring hospital productivity.

    Science.gov (United States)

    Serway, G D; Strum, D W; Haug, W F

    1987-08-01

    This article explores the premise that the appropriateness and usefulness of typical hospital productivity measures have been affected by three changes in delivery: Organizational restructuring and other definition and data source changes that make full-time equivalent employee (FTE) measurements ambiguous. Transition to prospective payment (diagnosis-related groups). Increase in capitation (prepaid, at risk) programs. The effects of these changes on productivity management indicate the need for alternative productivity indicators. Several productivity measures that complement these changes in internal operations and the external hospital business environment are presented. These are based on an analysis of four hospitals within a multihospital system, and an illustration and interpretation of an array of measures, based on ten months of actual data, is provided. In conclusion, the recommendation is made for hospital management to collect an expanded set of productivity measures and review them in light of changing expense and revenue management schemes inherent in new payment modes. PMID:10312194

  4. Alternative indicators for measuring hospital productivity.

    Science.gov (United States)

    Serway, G D; Strum, D W; Haug, W F

    1987-08-01

    This article explores the premise that the appropriateness and usefulness of typical hospital productivity measures have been affected by three changes in delivery: Organizational restructuring and other definition and data source changes that make full-time equivalent employee (FTE) measurements ambiguous. Transition to prospective payment (diagnosis-related groups). Increase in capitation (prepaid, at risk) programs. The effects of these changes on productivity management indicate the need for alternative productivity indicators. Several productivity measures that complement these changes in internal operations and the external hospital business environment are presented. These are based on an analysis of four hospitals within a multihospital system, and an illustration and interpretation of an array of measures, based on ten months of actual data, is provided. In conclusion, the recommendation is made for hospital management to collect an expanded set of productivity measures and review them in light of changing expense and revenue management schemes inherent in new payment modes.

  5. Thin stillage supplementation greatly enhances bacterial cellulose production by Gluconacetobacter xylinus.

    Science.gov (United States)

    Wu, Jyh-Ming; Liu, Ren-Han

    2012-09-01

    Thin stillage (TS), a wastewater from rice wine distillery can well sustain the growth of Gluconacetobacter xylinus for production of bacterial cellulose (BC). When used as a supplement to the traditional BC production medium (Hestrin and Schramm medium), the enhancement of BC production increased with the amount of TS supplemented in a static culture of G. xylinus. When TS was employed to replace distilled water for preparing HS medium (100%TS-HS medium), the BC production in this 100%TS-HS medium was enhanced 2.5-fold to a concentration of 10.38 g/l with sugar to BC conversion yield of 57% after 7 days cultivation. The cost-free TS as a supplement in BC production medium not only can greatly enhance the BC production, but also can effectively dispose the nuisance wastewater of rice wine distillery.

  6. The effect of antibiotics on associated bacterial community of stored product mites.

    Directory of Open Access Journals (Sweden)

    Jan Kopecky

    Full Text Available Bacteria are associated with the gut, fat bodies and reproductive organs of stored product mites (Acari: Astigmata. The mites are pests due to the production of allergens. Addition of antibiotics to diets can help to characterize the association between mites and bacteria.Ampicillin, neomycin and streptomycin were added to the diets of mites and the effects on mite population growth (Acarus siro, Lepidoglyphus destructor and Tyrophagus putrescentiae and associated bacterial community structure were assessed. Mites were treated by antibiotic supplementation (1 mg g(-1 of diet for 21 days and numbers of mites and bacterial communities were analyzed and compared to the untreated control. Bacterial quantities, determined by real-time PCR, significantly decreased in antibiotic treated specimens from 5 to 30 times in A. siro and T. putrescentiae, while no decline was observed in L. destructor. Streptomycin treatment eliminated Bartonella-like bacteria in the both A. siro and T. putrescentiae and Cardinium in T. putrescentiae. Solitalea-like bacteria proportion increased in the communities of neomycin and streptomycin treated A. siro specimens. Kocuria proportion increased in the bacterial communities of ampicillin and streptomycin treated A. siro and neomycin and streptomycin treated L. destructor.The work demonstrated the changes of mite associated bacterial community under antibiotic pressure in pests of medical importance. Pre-treatment of mites by 1 mg g(-1 antibiotic diets improved mite fitness as indicated accelerated population growth of A. siro pretreated streptomycin and neomycin and L. destructor pretreated by neomycin. All tested antibiotics supplemented to diets caused the decrease of mite growth rate in comparison to the control diet.

  7. Biodegradation of Leonardite by an alkali-producing bacterial community and characterization of the degraded products.

    Science.gov (United States)

    Gao, Tong-Guo; Jiang, Feng; Yang, Jin-Shui; Li, Bao-Zhen; Yuan, Hong-Li

    2012-03-01

    In this study, three bacterial communities were obtained from 12 Leonardite samples with the aim of identifying a clean, effective, and economic technique for the dissolution of Leonardite, a type of low-grade coal, in the production of humic acid (HA). The biodegradation ability and characteristics of the degraded products of the most effective bacterial community (MCSL-2), which degraded 50% of the Leonardite within 21 days, were further investigated. Analyses of elemental composition, (13)C NMR, and Fourier transform infrared revealed that the contents of C, O, and aliphatic carbon were similar in biodegraded humic acid (bHA) and chemically (alkali) extracted humic acid (cHA). However, the N and carboxyl carbon contents of bHA was higher than that of cHA. Furthermore, a positive correlation was identified between the degradation efficiency and the increasing pH of the culture medium, while increases of manganese peroxidase and esterase activities were also observed. These data demonstrated that both alkali production and enzyme reactions were involved in Leonardite solubilization by MCSL-2, although the former mechanism predominated. No fungus was observed by microscopy. Only four bacterial phylotypes were recognized, and Bacillus licheniformis-related bacteria were identified as the main group in MCSL-2 by analysis of amplified 16S rRNA genes, thus demonstrating that Leonardite degradation ability has a limited distribution in bacteria. Hormone-like bioactivities of bHA were also detected. In this study, a bacterial community capable of Leonardite degradation was identified and the products characterized. These data implicate the use of such bacteria for the exploitation of Leonardite as a biofertilizer.

  8. Biodegradation of Leonardite by an alkali-producing bacterial community and characterization of the degraded products.

    Science.gov (United States)

    Gao, Tong-Guo; Jiang, Feng; Yang, Jin-Shui; Li, Bao-Zhen; Yuan, Hong-Li

    2012-03-01

    In this study, three bacterial communities were obtained from 12 Leonardite samples with the aim of identifying a clean, effective, and economic technique for the dissolution of Leonardite, a type of low-grade coal, in the production of humic acid (HA). The biodegradation ability and characteristics of the degraded products of the most effective bacterial community (MCSL-2), which degraded 50% of the Leonardite within 21 days, were further investigated. Analyses of elemental composition, (13)C NMR, and Fourier transform infrared revealed that the contents of C, O, and aliphatic carbon were similar in biodegraded humic acid (bHA) and chemically (alkali) extracted humic acid (cHA). However, the N and carboxyl carbon contents of bHA was higher than that of cHA. Furthermore, a positive correlation was identified between the degradation efficiency and the increasing pH of the culture medium, while increases of manganese peroxidase and esterase activities were also observed. These data demonstrated that both alkali production and enzyme reactions were involved in Leonardite solubilization by MCSL-2, although the former mechanism predominated. No fungus was observed by microscopy. Only four bacterial phylotypes were recognized, and Bacillus licheniformis-related bacteria were identified as the main group in MCSL-2 by analysis of amplified 16S rRNA genes, thus demonstrating that Leonardite degradation ability has a limited distribution in bacteria. Hormone-like bioactivities of bHA were also detected. In this study, a bacterial community capable of Leonardite degradation was identified and the products characterized. These data implicate the use of such bacteria for the exploitation of Leonardite as a biofertilizer. PMID:22075634

  9. Production and Characterization of a New Bacterial Cellulose/Poly(Vinyl Alcohol) Nanocomposite

    OpenAIRE

    Miguel Gama; Fernando Dourado; João Pedro Silva; Alexandre F. Leitão

    2013-01-01

    Bacterial cellulose (BC) is characterized for its high water holding capacity, high crystallinity, an ultrafine fiber network and high tensile strength. This work demonstrates the production of a new interpenetrated polymer network nanocomposite obtained through the incorporation of poly(vinyl alcohol) (PVA) on the BC matrix and evaluates the effect of oven drying on the morphological, mechanical and mass transfer properties of the composite membranes. Both the addition of PVA and oven drying...

  10. TECHNOLOGICAL MEASURES TO IMPROVE AUTOMOTIVE PRODUCT QUALITY

    OpenAIRE

    Gladkov, V.; Kruglov, S.

    2010-01-01

    The paper examines the basic technological measures aimed at improving product quality in automotive industry. While paying due attention to solving organizational and technological problems, including the development of certification systems for production processes, it is also necessary to improve the technical standards of specific technologies, equipment and materials as they largely determine product quality. Special emphasis is given to the importance of improving the production of auto...

  11. The bacterial abundance and production in the East China Sea:seasonal variations and relationships with the phytoplankton biomass and production

    Institute of Scientific and Technical Information of China (English)

    CHEN Bingzhang; HUANG Bangqin; XIE Yuyuan; GUO Cui; SONG Shuqun; LI Hongbo; LIU Hongbin

    2014-01-01

    The East China Sea is a productive marginal sea with a wide continental shelf and plays an important role in absorbing atmospheric carbon dioxide and transferring terrigenous organic matter to the open ocean. To investigate the roles of heterotrophic bacteria in the biogeochemical dynamics in the East China Sea, bacterial biomasses (BB) and productions (BP) were measured in four cruises. The spatial distributions of the BB and the BP were highly season-dependent. Affected by the Changjiang River discharge, the BB and the BP were high in shelf waters (bottom depth not deeper than 50 m) and generally decreased offshore in August 2009. In December 2009 to January 2010, and November to December 2010, the BB and the BP were high in waters with medium bottom depth. The onshore-offshore decreasing trends of the BB and the BP also existed in May-June 2011, when the BB was significantly higher than in other cruises in shelf break waters (bottom depth deeper than 50 m but not deeper than 200 m). The results of generalized additive models (GAM) suggest that the BB increased with the temperature at a range of 8-20°C, increased with the chlorophyll concentration at a range of 0.02-3.00 mg/m3 and then declining, and decreased with the salinity from 28 to 35. The relationship between the temperature and the log-transformed bacterial specific growth rate (SGR) was linear. The estimated temperature coefficient (Q10) of the SGR was similar with that of the phytoplankton growth. The SGR also increased with the chlorophyll concentration. The ratio of the bacterial to phytoplankton production ranged from less than 0.01 to 0.40, being significantly higher in November-December 2010 than in May-June 2011. Calculated from the bacterial production and growth efficiency, the bacterial respiration consumed, on average, 59%, 72%and 23%of the primary production in August 2009, November-December 2010, and May-June 2011, respectively.

  12. Size of bacterial ice-nucleation sites measured in situ by radiation inactivation analysis

    International Nuclear Information System (INIS)

    Four bacterial species are known to catalyze ice formation at temperatures just below 00C. To better understand the relationship between the molecular structure of bacterial ice-nucleation site(s) and the quantitative and qualitative features of the ice-nucleation-active phenotype, the authors determined by γ-radiation analysis the in situ size of ice-nucleation sites in strains of Pseudomonas syringae and Erwinia herbicola and in Escherichia coli HB101 carrying the plasmid pICE1.1. Lyophilized cells of each bacterial strain were irradiated with a flux of γ radiation from 0 to 10.2 Mrad. Differential concentrations of active ice nuclei decreased as a first-order function of radiation dose in all strains as temperature was decreased from -20C to -140C in 10C intervals. Sizes of ice nuclei were calculated from the +-radiation flux at which 37% of initial ice nuclei active within each 10C temperature interval remained. The minimum mass of a functional ice nucleus was about 150 kDa for all strains. The size of ice nuclei increased logarithmically with increasing temperature from -120CC to -20C, where the estimated nucleant mass was 19,000 kDa. The ice nucleant in these three bacterial species may represent an oligomeric structure, composed at least in part of an ice gene product that can self-associate to assume many possible sizes

  13. Contribution of airborne microbes to bacterial production and N2 fixation in seawater upon aerosol deposition

    Science.gov (United States)

    Rahav, Eyal; Ovadia, Galit; Paytan, Adina; Herut, Barak

    2016-01-01

    Aerosol deposition may supply a high diversity of airborne microbes, which can affect surface microbial composition and biological production. This study reports a diverse microbial community associated with dust and other aerosol particles, which differed significantly according to their geographical air mass origin. Microcosm bioassay experiments, in which aerosols were added to sterile (0.2 µm filtered and autoclaved) SE Mediterranean Sea (SEMS) water, were performed to assess the potential impact of airborne bacteria on bacterial abundance, production, and N2 fixation. Significant increase was observed in all parameters within a few hours, and calculations suggest that airborne microbes can account for one third in bacterial abundance and 50-100% in bacterial production and N2-fixation rates following dust/aerosol amendments in the surface SEMS. We show that dust/aerosol deposition can be a potential source of a wide array of microorganisms, which may impact microbial composition and food web dynamics in oligotrophic marine systems such as the SEMS.

  14. Dark fermentative biohydrogen production by mesophilic bacterial consortia isolated from riverbed sediments

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Sneha; Sudhakaran, Anu K.; Sarma, Priyangshu Manab; Subudhi, Sanjukta; Mandal, Ajoy Kumar; Lal, Banwari [Environmental and Industrial Biotechnology Division, The Energy and Resources Institute (TERI), Habitat Place, Darbari Seth Block, Lodhi Road, New Delhi 110003 (India); Gandham, Ganesh [Hindustan Petroleum Corporation Limited, Mumbai Refinery, B. D. Patil Marg, Mahul, Mumbai 400074 (India)

    2010-10-15

    Dark fermentative bacterial strains were isolated from riverbed sediments and investigated for hydrogen production. A series of batch experiments were conducted to study the effect of pH, substrate concentration and temperature on hydrogen production from a selected bacterial consortium, TERI BH05. Batch experiments for fermentative conversion of sucrose, starch, glucose, fructose, and xylose indicated that TERI BH05 effectively utilized all the five sugars to produce fermentative hydrogen. Glucose was the most preferred carbon source indicating highest hydrogen yields of 22.3 mmol/L. Acetic and butyric acid were the major soluble metabolites detected. Investigation on optimization of pH, temperature, and substrate concentration revealed that TERI BH05 produced maximum hydrogen at 37 C, pH 6 with 8 g/L of glucose supplementation and maximum yield of hydrogen production observed was 2.0-2.3 mol H{sub 2}/mol glucose. Characterization of TERI BH05 revealed the presence of two different bacterial strains showing maximum homology to Clostridium butyricum and Clostridium bifermentans. (author)

  15. Bacterial stress enrichment enhances anaerobic hydrogen production in cattle manure sludge.

    Science.gov (United States)

    Cheong, Dae-Yeol; Hansen, Conly L

    2006-10-01

    Methodology was evaluated to selectively enrich hydrogen-producing species present in biological sludge produced during organic wastewater treatment. The influence of bacterial stress enrichment on anaerobic hydrogen-producing microorganisms was investigated in batch tests using serum bottles. Enrichment conditions investigated included application of acute physical and chemical stresses: wet heat, dry heat and desiccation, use of a methanogen inhibitor, freezing and thawing, and chemical acidification with and without preacidification of the sludge at pH 3. For each enrichment sample, cultivation pH value was set at an initial value of 7. After application of selective enrichment (by bacterial stress), hydrogen production was significantly higher than that of untreated original sludge. Hydrogen production from the inocula with bacterial stress enrichment was 1.9-9.8 times greater when compared with control sludge. Chemical acidification using perchloric acid showed the best hydrogen production potential, irrespective of preacidification. Enhancement is due to the selective capture of hydrogen-producing sporeformers, which induces altered anaerobic fermentative metabolism. PMID:16525779

  16. Heterotrophic bacterial production and metabolic balance during the VAHINE mesocosm experiment in the New Caledonia lagoon

    Science.gov (United States)

    Van Wambeke, France; Pfreundt, Ulrike; Barani, Aude; Berthelot, Hugo; Moutin, Thierry; Rodier, Martine; Hess, Wolfgang R.; Bonnet, Sophie

    2016-06-01

    Studies investigating the fate of diazotrophs through the microbial food web are lacking, although N2 fixation can fuel up to 50 % of new production in some oligotrophic oceans. In particular, the role played by heterotrophic prokaryotes in this transfer is largely unknown. In the frame of the VAHINE (VAriability of vertical and tropHIc transfer of diazotroph derived N in the south wEst Pacific) experiment, three replicate large-volume (˜ 50 m3) mesocosms were deployed for 23 days in the new Caledonia lagoon and were intentionally fertilized on day 4 with dissolved inorganic phosphorus (DIP) to stimulate N2 fixation. We specifically examined relationships between heterotrophic bacterial production (BP) and N2 fixation or primary production, determined bacterial growth efficiency and established carbon budgets. BP was statistically higher during the second phase of the experiment (P2: days 15-23), when chlorophyll biomass started to increase compared to the first phase (P1: days 5-14). Phosphatase alkaline activity increased drastically during the second phase of the experiment, showing adaptations of microbial populations after utilization of the added DIP. Notably, among autotrophs, Synechococcus abundances increased during P2, possibly related to its capacity to assimilate leucine and to produce alkaline phosphatase. Bacterial growth efficiency based on the carbon budget (27-43 %), was notably higher than generally cited for oligotrophic environments and discussed in links with the presence of abundant species of bacteria expressing proteorhodopsin. The main fates of gross primary production (particulate + dissolved) were respiration (67 %) and export through sedimentation (17 %). BP was highly correlated with particulate primary production and chlorophyll biomass during both phases of the experiment but was slightly correlated, and only during P2 phase, with N2 fixation rates. Heterotrophic bacterial production was strongly stimulated after mineral N enrichment

  17. Recombinant plants provide a new approach to the production of bacterial polysaccharide for vaccines.

    Directory of Open Access Journals (Sweden)

    Claire M Smith

    Full Text Available Bacterial polysaccharides have numerous clinical or industrial uses. Recombinant plants could offer the possibility of producing bacterial polysaccharides on a large scale and free of contaminating bacterial toxins and antigens. We investigated the feasibility of this proposal by cloning and expressing the gene for the type 3 synthase (cps3S of Streptococcus pneumoniae in Nicotinia tabacum, using the pCambia2301 vector and Agrobacterium tumefaciens-mediated gene transfer. In planta the recombinant synthase polymerised plant-derived UDP-glucose and UDP-glucuronic acid to form type 3 polysaccharide. Expression of the cps3S gene was detected by RT-PCR and production of the pneumococcal polysaccharide was detected in tobacco leaf extracts by double immunodiffusion, Western blotting and high-voltage paper electrophoresis. Because it is used a component of anti-pneumococcal vaccines, the immunogenicity of the plant-derived type 3 polysaccharide was tested. Mice immunised with extracts from recombinant plants were protected from challenge with a lethal dose of pneumococci in a model of pneumonia and the immunised mice had significantly elevated levels of serum anti-pneumococcal polysaccharide antibodies. This study provides the proof of the principle that bacterial polysaccharide can be successfully synthesised in plants and that these recombinant polysaccharides could be used as vaccines to protect against life-threatening infections.

  18. "Productivity performance measurement - follow-up"

    DEFF Research Database (Denmark)

    Kristensen, Troels

    2008-01-01

    The Danish Ministry of Health has published the third annual report on hospital productivity. This experience has contributed to policy goals becoming more detailed and ambitious. New policy goals are: to include hospital productivity measures at less aggregated levels, to include labour producti......The Danish Ministry of Health has published the third annual report on hospital productivity. This experience has contributed to policy goals becoming more detailed and ambitious. New policy goals are: to include hospital productivity measures at less aggregated levels, to include labour...

  19. Bacterial dynamics during yearlong spontaneous fermentation for production of ngari, a dry fermented fish product of Northeast India.

    Science.gov (United States)

    Devi, Khunjamayum Romapati; Deka, Manab; Jeyaram, Kumaraswamy

    2015-04-16

    Ngari is the most popular traditionally processed non-salted fish product, prepared from sun-dried small cyprinid fish Puntius sophore (Ham.) in Manipur state of Northeast India. The microbial involvement in ngari production remained uncertain due to its low moisture content and yearlong incubation in anaerobically sealed earthen pots without any significant change in total microbial count. The culture-independent PCR-DGGE analysis used during this study confirmed a drastic bacterial community structural change in comparison to its raw material. To understand the bacterial dynamics during this dry fermentation, time series samples collected over a period of nine months through destructive sampling from two indigenous ngari production centres were analysed by using both culture-dependent and culture-independent molecular methods. A total of 210 bacteria isolated from the samples were identified by amplified ribosomal DNA restriction analysis (ARDRA) based grouping and 16S rRNA gene sequence similarity analysis. The dominant bacteria were Staphylococcus cohnii subsp. cohnii (38.0%), Tetragenococcus halophilus subsp. flandriensis (16.8%), a novel phylotype related to Lactobacillus pobuzihii (7.2%), Enterococcus faecium (7.2%), Bacillus indicus (6.3%) and Staphylococcus carnosus (3.8%). Distinct bacterial dynamics with the emergence of T. halophilus at third month (10(6)CFU/g), L. pobuzihii at sixth month (10(6)CFU/g), S. carnosus at three to six months (10(4)CFU/g) and B. indicus at six to nine months (10(5)CFU/g) in both the production centres was observed during ngari fermentation. However, the other two dominant bacteria S. cohnii and E. faecium were isolated throughout the fermentation with the population of 10(6)CFU/g and 10(4)CFU/g respectively. Culture-independent PCR-DGGE analysis further showed the presence of additional species, in which Kocuria halotolerans and Macrococcus caseolyticus disappeared during fermentation while Clostridium irregulare and

  20. Improvement production of bacterial cellulose by semi-continuous process in molasses medium.

    Science.gov (United States)

    Cakar, Fatih; Ozer, Işılay; Aytekin, A Özhan; Sahin, Fikrettin

    2014-06-15

    Bacterial cellulose (BC) has unique properties such as structural, functional, physical and chemical. The mass production of BC for industrial application has recently become attractive to produce more economical and high productive cellulose. In this study, to improve the productivity of bacterial cellulose (BC), BC production by Gluconacetobacter xylinus FC01 was investigated in molasses medium with static semi-continuous operation mode. Cell dry weight, polysaccharide, sugar and cellulose concentrations were monitored and cellulose was characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The highest cellulose yield (1.637 g/L) was obtained in SCP50-7d, which molasses of 1/2 ratio for 7 days by static semi-continuous operation mode. The results show that BC can be highly produced by G. xylinus in molasses with static semi-continuous process than batch process. We claimed that low-cost medium with semi-continuous operation mode in static culture is a good candidate for industrial scale BC productions.

  1. Bioaugmentation of Hydrogenispora ethanolica LX-B affects hydrogen production through altering indigenous bacterial community structure.

    Science.gov (United States)

    Yang, Zhiman; Guo, Rongbo; Shi, Xiaoshuang; He, Shuai; Wang, Lin; Dai, Meng; Qiu, Yanling; Dang, Xiaoxiao

    2016-07-01

    Bioaugmentation can facilitate hydrogen production from complex organic substrates, but it still is unknown how indigenous microbial communities respond to the added bacteria. Here, using a Hydrogenispora ethanolica LX-B (named as LX-B) bioaugmentation experiments, the distribution of metabolites and the responses of indigenous bacterial communities were investigated via batch cultivation (BC) and repeated batch cultivation (RBC). In BC the LX-B/sludge ratio of 0.12 achieved substantial high hydrogen yield, which was over twice that of control. In RBC one-time bioaugmentation and repeated batch bioaugmentation of LX-B resulted in the hydrogen yield that was average 1.2-fold and 0.8-fold higher than that in control, respectively. This improved hydrogen production performance mainly benefited from a shift in composition of the indigenous bacterial community caused by LX-B bioaugmentation. The findings represented an important step in understanding the relationship between bioaugmentation, a shift in bacterial communities, and altered bioreactor performance. PMID:27023388

  2. Characterization of the bacterial metagenome in an industrial algae bioenergy production system

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Shi [Chinese Academy of Sciences; Fulbright, Scott P [Colorado State University; Zeng, Xiaowei [Chinese Academy of Sciences; Yates, Tracy [Solix Biofuels; Wardle, Greg [Solix Biofuels; Chisholm, Stephen T [Colorado State University; Xu, Jian [Chinese Academy of Sciences; Lammers, Peter [New Mexico State University

    2011-03-16

    Cultivation of oleaginous microalgae for fuel generally requires growth of the intended species to the maximum extent supported by available light. The presence of undesired competitors, pathogens and grazers in cultivation systems will create competition for nitrate, phosphate, sulfate, iron and other micronutrients in the growth medium and potentially decrease microalgal triglyceride production by limiting microalgal health or cell density. Pathogenic bacteria may also directly impact the metabolism or survival of individual microalgal cells. Conversely, symbiotic bacteria that enhance microalgal growth may also be present in the system. Finally, the use of agricultural and municipal wastes as nutrient inputs for microalgal production systems may lead to the introduction and proliferation of human pathogens or interfere with the growth of bacteria with beneficial effects on system performance. These considerations underscore the need to understand bacterial community dynamics in microalgal production systems in order to assess microbiome effects on microalgal productivity and pathogen risks. Here we focus on the bacterial component of microalgal production systems and describe a pipeline for metagenomic characterization of bacterial diversity in industrial cultures of an oleaginous alga, Nannochloropsis salina. Environmental DNA was isolated from 12 marine algal cultures grown at Solix Biofuels, a region of the 16S rRNA gene was amplified by PCR, and 16S amplicons were sequenced using a 454 automated pyrosequencer. The approximately 70,000 sequences that passed quality control clustered into 53,950 unique sequences. The majority of sequences belonged to thirteen phyla. At the genus level, sequences from all samples represented 169 different genera. About 52.94% of all sequences could not be identified at the genus level and were classified at the next highest possible resolution level. Of all sequences, 79.92% corresponded to 169 genera and 70 other taxa. We

  3. Auto-production of biosurfactants reverses the coffee ring effect in a bacterial system

    Science.gov (United States)

    Sempels, Wouter; de Dier, Raf; Mizuno, Hideaki; Hofkens, Johan; Vermant, Jan

    2013-04-01

    The deposition of material at the edge of evaporating droplets, known as the ‘coffee ring effect’, is caused by a radially outward capillary flow. This phenomenon is common to a wide array of systems including colloidal and bacterial systems. The role of surfactants in counteracting these coffee ring depositions is related to the occurrence of local vortices known as Marangoni eddies. Here we show that these swirling flows are universal, and not only lead to a uniform deposition of colloids but also occur in living bacterial systems. Experiments on Pseudomonas aeruginosa suggest that the auto-production of biosurfactants has an essential role in creating a homogeneous deposition of the bacteria upon drying. Moreover, at biologically relevant conditions, intricate time-dependent flows are observed in addition to the vortex regime, which are also effective in reversing the coffee ring effect at even lower surfactant concentrations.

  4. Variable effects of dispersal on productivity of bacterial communities due to changes in functional trait composition

    DEFF Research Database (Denmark)

    Severin, Ina; Östman, Örjan; Lindström, Eva S.

    2013-01-01

    ) a dialysis bag experiment where the dispersal rate among six communities was manipulated and the subsequent change in bacterial diversity and growth rate was recorded, and (B) a regrowth experiment where we manipulated available resources to study how well a taxon grows on certain organic carbon resources, i......Previous studies have shown variable relationships between dispersal rate and ecosystem functioning, but the reasons for and mechanisms behind variable dispersal rate - functioning patterns are currently unknown. In this study we used six bacterial lake water communities in a laboratory experiment...... in order to investigate how dispersal among communities influences community productivity by evaluating three different mechanisms: 1) changes in taxonomic diversity, 2) changes in phylogenetic diversity or 3) changes in the composition of functional traits. The experiment was conducted in two phases; (A...

  5. Bacterial Glycosyltransferases: Challenges and opportunities of a highly diverse enzyme class toward tailoring natural products

    Directory of Open Access Journals (Sweden)

    Jochen eSchmid

    2016-02-01

    Full Text Available The enzyme subclass of glycosyltransferases (EC 2.4 currently comprises 97 families as specified by CAZy classification. One of their important roles is in the biosynthesis of disaccharides, oligosaccharides and polysaccharides by catalyzing the transfer of sugar moieties from activated donor molecules to other sugar molecules. In addition glycosyltransferases also catalyze the transfer of sugar moieties onto aglycons, which is of great relevance for the synthesis of many high value natural products. Bacterial glycosyltransferases show a higher sequence similarity in comparison to mammalian ones. Even when most glycosyltransferases are poorly explored, state of the art technologies, such as protein engineering, domain swapping or computational analysis strongly enhance our understanding and utilization of these very promising classes of proteins. This perspective article will focus on bacterial glycosyltransferases, especially on classification, screening and engineering strategies to alter substrate specificity. The future development in these fields as well as obstacles and challenges will be highlighted and discussed.

  6. 2,4,6-Trinitrotoluene mineralization and bacterial production rates of natural microbial assemblages from coastal sediments

    International Nuclear Information System (INIS)

    The nitrogenous energetic constituent, 2,4,6-Trinitrotoluene (TNT), is widely reported to be resistant to bacterial mineralization (conversion to CO2); however, these studies primarily involve bacterial isolates from freshwater where bacterial production is typically limited by phosphorus. This study involved six surveys of coastal waters adjacent to three biome types: temperate broadleaf, northern coniferous, and tropical. Capacity to catabolize and mineralize TNT ring carbon to CO2 was a common feature of natural sediment assemblages from these coastal environments (ranging to 270+/-38 μg C kg-1 d-1). More importantly, these mineralization rates comprised a significant proportion of total heterotrophic production. The finding that most natural assemblages surveyed from these ecosystems can mineralize TNT ring carbon to CO2 is consistent with recent reports that assemblage components can incorporate TNT ring carbon into bacterial biomass. These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments. - Highlights: → TNT mineralization is a common feature of natural bacterial assemblages in coastal sediments. → TNT mineralization rates comprised a significant proportion of total heterotrophic production. → These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments. - The capacity to mineralize TNT ring carbon to CO2 is a common feature of natural bacterial assemblages in coastal sediment.

  7. 2,4,6-Trinitrotoluene mineralization and bacterial production rates of natural microbial assemblages from coastal sediments

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, Michael T., E-mail: michael.montgomery@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Coffin, Richard B., E-mail: richard.coffin@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Boyd, Thomas J., E-mail: thomas.boyd@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Smith, Joseph P., E-mail: joseph.smith@nrl.navy.mil [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Walker, Shelby E., E-mail: Shelby.Walker@noaa.gov [Naval Research Laboratory, Marine Biogeochemistry Section, Code 6114, 4555 Overlook Avenue, Washington, DC 20375 (United States); Osburn, Christopher L., E-mail: chris_osburn@ncsu.edu [Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, NC 27695 (United States)

    2011-12-15

    The nitrogenous energetic constituent, 2,4,6-Trinitrotoluene (TNT), is widely reported to be resistant to bacterial mineralization (conversion to CO{sub 2}); however, these studies primarily involve bacterial isolates from freshwater where bacterial production is typically limited by phosphorus. This study involved six surveys of coastal waters adjacent to three biome types: temperate broadleaf, northern coniferous, and tropical. Capacity to catabolize and mineralize TNT ring carbon to CO{sub 2} was a common feature of natural sediment assemblages from these coastal environments (ranging to 270+/-38 {mu}g C kg{sup -1} d{sup -1}). More importantly, these mineralization rates comprised a significant proportion of total heterotrophic production. The finding that most natural assemblages surveyed from these ecosystems can mineralize TNT ring carbon to CO{sub 2} is consistent with recent reports that assemblage components can incorporate TNT ring carbon into bacterial biomass. These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments. - Highlights: > TNT mineralization is a common feature of natural bacterial assemblages in coastal sediments. > TNT mineralization rates comprised a significant proportion of total heterotrophic production. > These data counter the widely held contention that TNT is recalcitrant to bacterial catabolism of the ring carbon in natural environments. - The capacity to mineralize TNT ring carbon to CO{sub 2} is a common feature of natural bacterial assemblages in coastal sediment.

  8. Spring constants and adhesive properties of native bacterial biofilm cells measured by atomic force microscopy.

    Science.gov (United States)

    Volle, C B; Ferguson, M A; Aidala, K E; Spain, E M; Núñez, M E

    2008-11-15

    Bacterial biofilms were imaged by atomic force microscopy (AFM), and their elasticity and adhesion to the AFM tip were determined from a series of tip extension and retraction cycles. Though the five bacterial strains studied included both Gram-negative and -positive bacteria and both environmental and laboratory strains, all formed simple biofilms on glass surfaces. Cellular spring constants, determined from the extension portion of the force cycle, varied between 0.16+/-0.01 and 0.41+/-0.01 N/m, where larger spring constants were measured for Gram-positive cells than for Gram-negative cells. The nonlinear regime in the extension curve depended upon the biomolecules on the cell surface: the extension curves for the smooth Gram-negative bacterial strains with the longest lipopolysaccharides on their surface had a larger nonlinear region than the rough bacterial strain with shorter lipopolysaccharides on the surface. Adhesive forces between the retracting silicon nitride tip and the cells varied between cell types in terms of the force components, the distance components, and the number of adhesion events. The Gram-negative cells' adhesion to the tip showed the longest distance components, sometimes more than 1 microm, whereas the shortest distance adhesion events were measured between the two Gram-positive cell types and the tip. Fixation of free-swimming planktonic cells by NHS and EDC perturbed both the elasticity and the adhesive properties of the cells. Here we consider the biochemical meaning of the measured physical properties of simple biofilms and implications to the colonization of surfaces in the first stages of biofilm formation. PMID:18815013

  9. Bacterial production, glucosidase activity and particle-associated carbohydrates in Dona Paula bay, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Bhaskar, P.V.; Bhosle, N.B.

    Size-fractionated bacterial production, abundance and Alpha - and Beta - glucosidase enzyme activities were studied with respect to changes in hydrography, total suspended matter (TSM), chlorophyll a, particulate organic carbon and nitrogen ratio...

  10. Magnesium aminoclay enhances lipid production of mixotrophic Chlorella sp. KR-1 while reducing bacterial populations.

    Science.gov (United States)

    Kim, Bohwa; Praveenkumar, Ramasamy; Lee, Jiye; Nam, Bora; Kim, Dong-Myung; Lee, Kyubock; Lee, Young-Chul; Oh, You-Kwan

    2016-11-01

    Improving lipid productivity and preventing overgrowth of contaminating bacteria are critical issues relevant to the commercialization of the mixotrophic microalgae cultivation process. In this paper, we report the use of magnesium aminoclay (MgAC) nanoparticles for enhanced lipid production from oleaginous Chlorella sp. KR-1 with simultaneous control of KR-1-associated bacterial growth in mixotrophic cultures with glucose as the model substrate. Addition of 0.01-0.1g/L MgAC promoted microalgal biomass production better than the MgAC-less control, via differential biocidal effects on microalgal and bacterial cells (the latter being more sensitive to MgAC's bio-toxicity than the former). The inhibition effect of MgAC on co-existing bacteria was, as based on density-gradient-gel-electrophoresis (DGGE) analysis, largely dosage-dependent and species-specific. MgAC also, by inducing an oxidative stress environment, increased both the cell size and lipid content of KR-1, resulting in a considerable, ∼25% improvement of mixotrophic algal lipid productivity (to ∼410mgFAME/L/d) compared with the untreated control. PMID:27543952

  11. Magnesium aminoclay enhances lipid production of mixotrophic Chlorella sp. KR-1 while reducing bacterial populations.

    Science.gov (United States)

    Kim, Bohwa; Praveenkumar, Ramasamy; Lee, Jiye; Nam, Bora; Kim, Dong-Myung; Lee, Kyubock; Lee, Young-Chul; Oh, You-Kwan

    2016-11-01

    Improving lipid productivity and preventing overgrowth of contaminating bacteria are critical issues relevant to the commercialization of the mixotrophic microalgae cultivation process. In this paper, we report the use of magnesium aminoclay (MgAC) nanoparticles for enhanced lipid production from oleaginous Chlorella sp. KR-1 with simultaneous control of KR-1-associated bacterial growth in mixotrophic cultures with glucose as the model substrate. Addition of 0.01-0.1g/L MgAC promoted microalgal biomass production better than the MgAC-less control, via differential biocidal effects on microalgal and bacterial cells (the latter being more sensitive to MgAC's bio-toxicity than the former). The inhibition effect of MgAC on co-existing bacteria was, as based on density-gradient-gel-electrophoresis (DGGE) analysis, largely dosage-dependent and species-specific. MgAC also, by inducing an oxidative stress environment, increased both the cell size and lipid content of KR-1, resulting in a considerable, ∼25% improvement of mixotrophic algal lipid productivity (to ∼410mgFAME/L/d) compared with the untreated control.

  12. Light-Stimulated Bacterial Production and Amino Acid Assimilation by Cyanobacteria and Other Microbes in the North Atlantic Ocean▿

    OpenAIRE

    Vanessa K Michelou; Cottrell, Matthew T.; Kirchman, David L.

    2007-01-01

    We examined the contribution of photoheterotrophic microbes—those capable of light-mediated assimilation of organic compounds—to bacterial production and amino acid assimilation along a transect from Florida to Iceland from 28 May to 9 July 2005. Bacterial production (leucine incorporation at a 20 nM final concentration) was on average 30% higher in light than in dark-incubated samples, but the effect varied greatly (3% to 60%). To further characterize this light effect, we examined the abund...

  13. Bacterial production in the water column of small streams highly depends on terrestrial dissolved organic carbon

    Science.gov (United States)

    Graeber, Daniel; Poulsen, Jane R.; Rasmussen, Jes J.; Kronvang, Brian; Zak, Dominik; Kamjunke, Norbert

    2016-04-01

    In the recent years it has become clear that the largest part of the terrestrial dissolved organic carbon (DOC) pool is removed on the way from the land to the ocean. Yet it is still unclear, where in the freshwater systems terrestrial DOC is actually taken up, and for streams DOC uptake was assumed to happen mostly at the stream bottom (benthic zone). However, a recent monitoring study implies that water column but not benthic bacteria are strongly affected by the amount and composition of DOM entering streams from the terrestrial zone. We conducted an experiment to compare the reaction of the bacterial production and heterotrophic uptake in the water column and the benthic zone to a standardized source of terrestrial DOC (leaf leachate from Beech litter). In detail, we sampled gravel and water from eight streams with a gradient in stream size and land use. For each stream four different treatments were incubated at 16°C for three days and each stream: filtered stream water with gravel stones (representing benthic zone bacteria) or unfiltered stream water (representing water column bacteria), both either with (n = 5) or, without (n = 3) leaf leachate. We found that the bacterial uptake of leaf litter DOC was higher for the benthic zone likely due to the higher bacterial production compared to the water column. In contrast, the bacterial production per amount of leaf leachate DOC taken up was significantly higher for the bacteria in the water column than for those in the benthic zone. This clearly indicates a higher growth efficiency with the leaf leachate DOC for the bacteria in the water column than in the benthic zone. We found a high variability for the growth efficiency in the water column, which was best explained by a negative correlation of the DOC demand with stream width (R² = 0.86, linear correlation of log-transformed data). This was not the case for the benthic zone bacteria (R² = 0.02). This implies that water column bacteria in very small streams

  14. Target Product Profile for a Diagnostic Assay to Differentiate between Bacterial and Non-Bacterial Infections and Reduce Antimicrobial Overuse in Resource-Limited Settings: An Expert Consensus

    Science.gov (United States)

    Dittrich, Sabine; Tadesse, Birkneh Tilahun; Moussy, Francis; Chua, Arlene; Zorzet, Anna; Tängdén, Thomas; Dolinger, David L.; Page, Anne-Laure; Crump, John A.; D’Acremont, Valerie; Bassat, Quique; Lubell, Yoel; Newton, Paul N.; Heinrich, Norbert; Rodwell, Timothy J.; González, Iveth J.

    2016-01-01

    Acute fever is one of the most common presenting symptoms globally. In order to reduce the empiric use of antimicrobial drugs and improve outcomes, it is essential to improve diagnostic capabilities. In the absence of microbiology facilities in low-income settings, an assay to distinguish bacterial from non-bacterial causes would be a critical first step. To ensure that patient and market needs are met, the requirements of such a test should be specified in a target product profile (TPP). To identify minimal/optimal characteristics for a bacterial vs. non-bacterial fever test, experts from academia and international organizations with expertise in infectious diseases, diagnostic test development, laboratory medicine, global health, and health economics were convened. Proposed TPPs were reviewed by this working group, and consensus characteristics were defined. The working group defined non-severely ill, non-malaria infected children as the target population for the desired assay. To provide access to the most patients, the test should be deployable to community health centers and informal health settings, and staff should require 90% and >80% for sensitivity and specificity, respectively. Other key characteristics, to account for the challenging environment at which the test is targeted, included: i) time-to-result <10 min (but maximally <2 hrs); ii) storage conditions at 0–40°C, ≤90% non-condensing humidity with a minimal shelf life of 12 months; iii) operational conditions of 5–40°C, ≤90% non-condensing humidity; and iv) minimal sample collection needs (50–100μL, capillary blood). This expert approach to define assay requirements for a bacterial vs. non-bacterial assay should guide product development, and enable targeted and timely efforts by industry partners and academic institutions. PMID:27559728

  15. Size of bacterial ice-nucleation sites measured in situ by radiation inactivation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Govindarajan, A.G.; Lindow, S.E.

    1988-03-01

    Four bacterial species are known to catalyze ice formation at temperatures just below 0/sup 0/C. To better understand the relationship between the molecular structure of bacterial ice-nucleation site(s) and the quantitative and qualitative features of the ice-nucleation-active phenotype, the authors determined by ..gamma..-radiation analysis the in situ size of ice-nucleation sites in strains of Pseudomonas syringae and Erwinia herbicola and in Escherichia coli HB101 carrying the plasmid pICE1.1. Lyophilized cells of each bacterial strain were irradiated with a flux of ..gamma.. radiation from 0 to 10.2 Mrad. Differential concentrations of active ice nuclei decreased as a first-order function of radiation dose in all strains as temperature was decreased from -2/sup 0/C to -14/sup 0/C in 1/sup 0/C intervals. Sizes of ice nuclei were calculated from the /sup +/-radiation flux at which 37% of initial ice nuclei active within each 1/sup 0/C temperature interval remained. The minimum mass of a functional ice nucleus was about 150 kDa for all strains. The size of ice nuclei increased logarithmically with increasing temperature from -12/sup 0/CC to -2/sup 0/C, where the estimated nucleant mass was 19,000 kDa. The ice nucleant in these three bacterial species may represent an oligomeric structure, composed at least in part of an ice gene product that can self-associate to assume many possible sizes.

  16. Development of a Low Input and sustainable Switchgrass Feedstock Production System Utilizing Beneficial Bacterial Endophytes

    Energy Technology Data Exchange (ETDEWEB)

    Mei, Chuansheng [IALR; Nowak, Jerzy [VPISU; Seiler, John [VPISU

    2014-10-24

    Switchgrass represents a promising feedstock crop for US energy sustainability. However, its broad utilization for bioenergy requires improvements of biomass yields and stress tolerance. In this DOE funded project, we have been working on harnessing beneficial bacterial endophytes to enhance switchgrass performance and to develop a low input feedstock production system for marginal lands that do not compete with the production of food crops. We have demonstrated that one of most promising plant growth-promoting bacterial endophytes, Burkholderia phytofirmans strain PsJN, is able to colonize roots and significantly promote growth of switchgrass cv. Alamo under in vitro, growth chamber, greenhouse, as well as field conditions. Furthermore, PsJN bacterization improved growth and development of switchgrass seedlings, significantly stimulated plant root and shoot growth, and tiller number in the field, and enhanced biomass accumulation on both poor (p<0.001) and rich (p<0.05) soils, with more effective stimulation of plant growth in low fertility soil. Plant physiology measurements showed that PsJN inoculated Alamo had consistently lower transpiration, lower stomatal conductance, and higher water use efficiency in greenhouse conditions. These physiological changes may significantly contribute to the recorded growth enhancement. PsJN inoculation rapidly results in an increase in photosynthetic rates which contributes to the advanced growth and development. Some evidence suggests that this initial growth advantage decreases with time when resources are not limited such as in greenhouse studies. Additionally, better drought resistance and drought hardening were observed in PsJN inoculated switchgrass. Using the DOE-funded switchgrass EST microarray, in a collaboration with the Genomics Core Facility at the Noble Foundation, we have determined gene expression profile changes in both responsive switchgrass cv. Alamo and non-responsive cv. Cave-in-Rock (CR) following Ps

  17. Measuring acceptance of new food product concepts

    DEFF Research Database (Denmark)

    Grunert, Klaus G; Perrea, Toula; Kügler, Jens

    New product concepts are routinely tested by showing members of the target group verbal and/or pictorial descriptions of new products and measuring reactions like overall liking and purchase intention. However, little is known about the processes leading to consumer acceptance or rejection of new...... product concepts. We develop a new form of concept test that, employing structural equation modelling, allows us to trace how different elements of the concept description contribute to acceptance or rejection of the concept, either cognitively mediated by triggering expectations about product quality...... and convenience, or without cognitive mediation (see figure). Using examples of new pork-based product concepts and data from four countries (Denmark, Germany, Netherlands, UK), we elaborate on the role of these two routes towards new product acceptance. We propose that the increased role of storytelling...

  18. Production of bacterial cellulose membranes in a modified airlift bioreactor by Gluconacetobacter xylinus.

    Science.gov (United States)

    Wu, Sheng-Chi; Li, Meng-Hsun

    2015-10-01

    In this study, a novel bioreactor for producing bacterial cellulose (BC) is proposed. Traditional BC production uses static culture conditions and produces a gelatinous membrane. The potential for using various types of bioreactor, including a stirred tank, conventional airlift, and modified airlift with a rectangular wire-mesh draft tube, in large-scale production has been investigated. The BC obtained from these bioreactors is fibrous or in pellet form. Our proposed airlift bioreactor produces a membrane-type BC from Gluconacetobacter xylinus, the water-holding capacity of which is greater than that of cellulose types produced using static cultivation methods. The Young's modulus of the product can be manipulated by varying the number of net plates in the modified airlift bioreactor. The BC membrane produced using the proposed bioreactor exhibits potential for practical application.

  19. Production of bacterial cellulose membranes in a modified airlift bioreactor by Gluconacetobacter xylinus.

    Science.gov (United States)

    Wu, Sheng-Chi; Li, Meng-Hsun

    2015-10-01

    In this study, a novel bioreactor for producing bacterial cellulose (BC) is proposed. Traditional BC production uses static culture conditions and produces a gelatinous membrane. The potential for using various types of bioreactor, including a stirred tank, conventional airlift, and modified airlift with a rectangular wire-mesh draft tube, in large-scale production has been investigated. The BC obtained from these bioreactors is fibrous or in pellet form. Our proposed airlift bioreactor produces a membrane-type BC from Gluconacetobacter xylinus, the water-holding capacity of which is greater than that of cellulose types produced using static cultivation methods. The Young's modulus of the product can be manipulated by varying the number of net plates in the modified airlift bioreactor. The BC membrane produced using the proposed bioreactor exhibits potential for practical application. PMID:25823854

  20. Partial Characteristics of Hydrogen Production by Fermentative Hydrogen-producing Bacterial Strain B49

    Institute of Scientific and Technical Information of China (English)

    Wang Xiangjing(王相晶); Ren Nanqi; Xiang Wensheng; Lin Ming; Guo Wanqian

    2003-01-01

    To investigate the characteristics of hydrogen production by a novel fermentative hydrogen-producing bacterial strain B49 (AF481148 in EMBL), batch experiments are conducted under different conditions. Hydrogen production has a correlation with cell growth and the consumption of glucose and soluble protein. The optimum pH for cell growth is 4.5±0.15. At acidic pH 4.0±0.15, the bacteria has the maximum accumulated hydrogen volume of 2382 ml/L culture and the maximum hydrogen evolution rate of 339.9 ml/L culture*h with 1% glucose. The optimum temperature for cell growth and hydrogen production is 35℃. In addition, fermentative hydrogen-producing bacterial strain B49 can generate hydrogen from the decomposition of other organic substrates such as wheat, soybean, corn, and potato. Moreover, it can also produce hydrogen from molasses wastewater and brewage wastewater, and hydrogen yields are 137.9 ml H2/g COD and 49.9 ml H2/g COD, respectively.

  1. ATLAS measurements of vector boson production

    CERN Document Server

    Debenedetti, Chiara; The ATLAS collaboration

    2016-01-01

    Vector boson production in pp collisions at 7, 8 and 13 TeV has been extensively studied by ATLAS. Recent results include the precision measurements of the transverse momentum of the Z/gamma* boson production, sensitive to soft resummation effects, hard jet emissions and electroweak corrections. A precise measurement of the angular coefficients of the Z­boson production tests the underlying QCD dynamics of the Drell­Yan process. A first measurement of the inclusive W and Z cross section at a cms energy of 13TeV has been derived. The Production of jets in association with a vector boson is an important process to study QCD in a multi­scale environment. Cross sections, differential in several kinematics variables, have been measured with the ATLAS detector and compared to state­of­the­art QCD calculations and Monte Carlo simulations. First measurements of vector boson + jets production have been performed at cms energies of 13TeV. An overview of these results is given.

  2. Coastal bacterial viability and production in the eastern English Channel: A case study during a Phaeocystis globosa bloom

    Science.gov (United States)

    Lamy, D.; Artigas, L. F.; Jauzein, C.; Lizon, F.; Cornille, V.

    2006-10-01

    Heterotrophic bacterial standing stocks (total and viable cells) and production were determined in the coastal surface waters of the eastern English Channel, during different stages of a phytoplankton succession. Two coastal zones of variable freshwater influence were surveyed within the 'coastal flow system' (Wimereux and Somme Bay) where massive and recurrent Phaeocystis globosa blooms take place in spring. The proportion of intact (MEM+) cells, assessed by the LIVE/DEAD® BacLight™ (L/D) method, varied from 15 to 94% at the two coastal stations studied (median of 46%). MEM+ and total (DAPI) cell counts were significantly correlated over the study period, whereas the higher proportion of MEM+ cells did not correspond to an elevated bacterial cell production (BP). Low levels of living (potentially active) cells were nevertheless responsible for the high productivity levels within the bacterial community when the P. globosa bloom declined. Our study revealed that the bacterial carbon production/primary production ratios (BCP/PP) showed broad variations (7 to 111%) within each site, going from low values (7-16%) when the bloom was the most productive, to higher values (61-111%) at the end of the bloom. This suggested (i) a temporal uncoupling between bacteria and phytoplankton throughout the bloom duration and (ii) a drastic change of the amount of PP potentially processed by the bacterial community among high and low productive periods. The BCP increase after the decline of the P. globosa bloom implies that, at this time, a large part of the phytoplankton-derived organic matter (OM) was remineralised via the bacterial heterotrophic production. With respect to the L/D results, this bacterial remineralisation was due to a small yet productive total cell fraction.

  3. Methane production and small intestinal bacterial overgrowth in children living in a slum

    Institute of Scientific and Technical Information of China (English)

    Carolina Santos Mello; Soraia Tahan; Lígia Cristina FL Melli; Mirian Silva do Carmo Rodrigues; Ricardo Martin Pereira de Mello; Isabel Cristina Affonso Scaletsky; Mauro Batista de Morais

    2012-01-01

    AIM:To analyze small intestinal bacterial overgrowth in school-aged children and the relationship between hydrogen and methane production in breath tests.METHODS:This transversal study included 85 children residing in a slum and 43 children from a private school,all aged between 6 and 10 years,in Osasco,Brazil.For characterization of the groups,data regarding the socioeconomic status and basic housing sanitary conditions were collected.Anthropometric data was obtained in children from both groups.All children completed the hydrogen (H2) and methane (CH4) breath test in order to assess small intestinal bacterial overgrowth (SIBO).SIBO was diagnosed when there was an increase in H2 ≥ 20 ppm or CH4 ≥ 10 ppm with regard to the fasting value until 60 min after lactulose ingestion.RESULTS:Children from the slum group had worse living conditions and lower nutritional indices than children from the private school.SIBO was found in 30.9% (26/84) of the children from the slum group and in 2.4% (1/41) from the private school group (P =0.0007).Greater hydrogen production in the small intestine was observed in children from the slum group when compared to children from the private school (P =0.007).A higher concentration of hydrogen in the small intestine (P < 0.001) and in the colon (P < 0.001) was observed among the children from the slum group with SIBO when compared to children from the slum group without SIBO.Methane production was observed in 63.1% (53/84) of the children from the slum group and in 19.5% (8/41) of the children from the private school group (P < 0.0001).Methane production was observed in 38/58 (65.5%) of the children without SIBO and in 15/26 (57.7%) of the children with SIBO from the slum.Colonic production of hydrogen was lower in methaneproducing children (P =0.017).CONCLUSION:Children who live in inadequate environmental conditions are at risk of bacterial overgrowth and methane production.Hydrogen is a substrate for methane

  4. Production of recombinant proteins and metabolites in yeasts: when are these systems better than bacterial production systems?

    Science.gov (United States)

    Porro, Danilo; Gasser, Brigitte; Fossati, Tiziana; Maurer, Michael; Branduardi, Paola; Sauer, Michael; Mattanovich, Diethard

    2011-02-01

    Recombinant DNA (rDNA) technologies allow the production of a wide range of peptides, proteins and metabolites from naturally non-producing cells. Since human insulin was the first heterologous compound produced in a laboratory in 1977, rDNA technology has become one of the most important technologies developed in the 20th century. Recombinant protein and metabolites production is a multi-billion dollar market. The development of a new product begins with the choice of the cell factory. The final application of the compound dictates the main criteria that should be taken into consideration: (1) quality, (2) quantity, (3) yield and (4) space time yield of the desired product. Quantity and quality are the most predominant requirements that must be considered for the commercial production of a protein. Quantity and yield are the requirements for the production of a metabolite. Finally, space time yield is crucial for any production process. It therefore becomes clear why the perfect host does not exist yet, and why-despite important advances in rDNA applications in higher eukaryotic cells-microbial biodiversity continues to represent a potential source of attractive cell factories. In this review, we compare the advantages and limitations of the principal yeast and bacterial workhorse systems. PMID:21125266

  5. Measurement of Highly Qualified Employees Productivity

    Directory of Open Access Journals (Sweden)

    Emese TOKARČÍKOVÁ

    2013-12-01

    Full Text Available Nowadays all economies are more and more based on knowledge and information. Economists therefore are increasingly interested in the measurement of productivity of highly qualified employees. While in the case of other factors of production (labour, land, capital we know the number of economic and statistical approaches how to deal with the measurement of efficiency or productivity, there is no single methodology in relation to highly qualified employees. Also there is a lack of an internationally agreed definition of highly qualified employees. This article offers possible approaches in this field focusing mainly on a staff segment with tertiary education. Although measuring of qualitative impacts is sometimes difficult, it does not mean that it is impossible. On the contrary, properly interpreted and applied indicators increase employment on the labour market and reinforce the positive contributions of highly qualified employees in the business.

  6. Bacterial cellulose production by Gluconacetobacter xylinus by employing alternative culture media.

    Science.gov (United States)

    Jozala, Angela Faustino; Pértile, Renata Aparecida Nedel; dos Santos, Carolina Alves; de Carvalho Santos-Ebinuma, Valéria; Seckler, Marcelo Martins; Gama, Francisco Miguel; Pessoa, Adalberto

    2015-02-01

    Bacterial cellulose (BC) is used in different fields as a biological material due to its unique properties. Despite there being many BC applications, there still remain many problems associated with bioprocess technology, such as increasing productivity and decreasing production cost. New technologies that use waste from the food industry as raw materials for culture media promote economic advantages because they reduce environmental pollution and stimulate new research for science sustainability. For this reason, BC production requires optimized conditions to increase its application. The main objective of this study was to evaluate BC production by Gluconacetobacter xylinus using industry waste, namely, rotten fruits and milk whey, as culture media. Furthermore, the structure of BC produced at different conditions was also determined. The culture media employed in this study were composed of rotten fruit collected from the disposal of free markets, milk whey from a local industrial disposal, and their combination, and Hestrin and Schramm media was used as standard culture media. Although all culture media studied produced BC, the highest BC yield-60 mg/mL-was achieved with the rotten fruit culture. Thus, the results showed that rotten fruit can be used for BC production. This culture media can be considered as a profitable alternative to generate high-value products. In addition, it combines environmental concern with sustainable processes that can promote also the reduction of production cost.

  7. Bacterial cellulose production by Gluconacetobacter xylinus by employing alternative culture media.

    Science.gov (United States)

    Jozala, Angela Faustino; Pértile, Renata Aparecida Nedel; dos Santos, Carolina Alves; de Carvalho Santos-Ebinuma, Valéria; Seckler, Marcelo Martins; Gama, Francisco Miguel; Pessoa, Adalberto

    2015-02-01

    Bacterial cellulose (BC) is used in different fields as a biological material due to its unique properties. Despite there being many BC applications, there still remain many problems associated with bioprocess technology, such as increasing productivity and decreasing production cost. New technologies that use waste from the food industry as raw materials for culture media promote economic advantages because they reduce environmental pollution and stimulate new research for science sustainability. For this reason, BC production requires optimized conditions to increase its application. The main objective of this study was to evaluate BC production by Gluconacetobacter xylinus using industry waste, namely, rotten fruits and milk whey, as culture media. Furthermore, the structure of BC produced at different conditions was also determined. The culture media employed in this study were composed of rotten fruit collected from the disposal of free markets, milk whey from a local industrial disposal, and their combination, and Hestrin and Schramm media was used as standard culture media. Although all culture media studied produced BC, the highest BC yield-60 mg/mL-was achieved with the rotten fruit culture. Thus, the results showed that rotten fruit can be used for BC production. This culture media can be considered as a profitable alternative to generate high-value products. In addition, it combines environmental concern with sustainable processes that can promote also the reduction of production cost. PMID:25472434

  8. Effects of aromatic compounds on the production of bacterial nanocellulose by Gluconacetobacter xylinus

    Science.gov (United States)

    2014-01-01

    Background Bacterial cellulose (BC) is a polymeric nanostructured fibrillar network produced by certain microorganisms, principally Gluconacetobacter xylinus. BC has a great potential of application in many fields. Lignocellulosic biomass has been investigated as a cost-effective feedstock for BC production through pretreatment and hydrolysis. It is well known that detoxification of lignocellulosic hydrolysates may be required to achieve efficient production of BC. Recent results suggest that phenolic compounds contribute to the inhibition of G. xylinus. However, very little is known about the effect on G. xylinus of specific lignocellulose-derived inhibitors. In this study, the inhibitory effects of four phenolic model compounds (coniferyl aldehyde, ferulic acid, vanillin and 4-hydroxybenzoic acid) on the growth of G. xylinus, the pH of the culture medium, and the production of BC were investigated in detail. The stability of the phenolics in the bacterial cultures was investigated and the main bioconversion products were identified and quantified. Results Coniferyl aldehyde was the most potent inhibitor, followed by vanillin, ferulic acid, and 4-hydroxybenzoic acid. There was no BC produced even with coniferyl aldehyde concentrations as low as 2 mM. Vanillin displayed a negative effect on the bacteria and when the vanillin concentration was raised to 2.5 mM the volumetric yield of BC decreased to ~40% of that obtained in control medium without inhibitors. The phenolic acids, ferulic acid and 4-hydroxybenzoic acid, showed almost no toxic effects when less than 2.5 mM. The bacterial cultures oxidized coniferyl aldehyde to ferulic acid with a yield of up to 81%. Vanillin was reduced to vanillyl alcohol with a yield of up to 80%. Conclusions This is the first investigation of the effect of specific phenolics on the production of BC by G. xylinus, and is also the first demonstration of the ability of G. xylinus to convert phenolic compounds. This study gives a

  9. Top pair production measurements at ATLAS.

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00445370

    2016-01-01

    Measurements of the inclusive and differential top-quark pair cross sections in proton-proton collisions at both 8 TeV and 13 TeV with the ATLAS detector at the Large Hadron Collider are presented. The inclusive measurements reach high precision and are compared to the best available theoretical calculations. Differential measurements of the kinematic properties of the top quark production are also discussed. These measurements, including results using boosted tops, probe our understanding of top pair production in the TeV regime. The results, extrapolated to particle and parton level, are compared to Monte Carlo generators implementing LO and NLO matrix elements matched with parton showers and NNLO QCD calculations.

  10. Bacterial production determined by [3H]thymidine incorporation in field rhizospheres as evaluated by comparison to rhizodeposition

    DEFF Research Database (Denmark)

    Christensen, Henrik; Rønn, Regin; Ekelund, Flemming;

    1995-01-01

    In a sandy loam soil cropped to barley bacterial production in the rhizosphere was compared to the results of a parallel investigation on rhizodeposition. Bacterial production was stimulated in the rhizosphere as revealed by an increased biomass of bacteria (643–883 µg C g-1 soil) and protozoa (7.......2–15 × 104 cells g-1 soil) as well as elevated thymidine incorporation (9.7–12 pmol g-1 soil) in rhizosphere soil compared to bulk soil. Rhizodeposition, as determined by several pulse labellings with 14CO2, was estimated to be 412 µg C g-1 dry wt soil in the 0–15 cm layer. Bacterial production......, as determined by incorporation of 3H-labelled thymidine converted to bacterial C, revealed a plant-induced formation of 1348 µg bacterial C g-1 soil in the 0–15 cm layer. This is probably the first estimate for bacterial production based on thymidine incorporation which has been compared to an estimate of C...

  11. Entropy product measure for multipartite pure states

    Institute of Scientific and Technical Information of China (English)

    CAO Wancang; LIU Dan; PAN Feng; LONG Guilu

    2006-01-01

    An entanglement measure for multipartite pure states is formulated using the product of the von Neumann entropy of the reduced density matrices of the constituents.Based on this new measure, all possible ways of the maximal entanglement of the triqubit pure states are studied in detail and all types of the maximal entanglement have been culate the degree of entanglement, and an improvement is given in the area near the zero entropy.

  12. On ws-convergence of product measures

    OpenAIRE

    Balder, E.J.

    2001-01-01

    A canonical redecomposition makes it possible to study the wstopology for measures on a product space by means of recent techniques developed for the narrow topology for transition probabilities Thus a central result is obtained that generalizes both Prohorovs theorem and Komlos theorem it is in terms of pointwise wconvergence of averages of transition measures Komlosconvergence New results for sequential wsconvergence follow these include two versions of Prohorovs theorem for relative sequen...

  13. Fed-Batch Production of Bacterial Ghosts Using Dielectric Spectroscopy for Dynamic Process Control.

    Science.gov (United States)

    Meitz, Andrea; Sagmeister, Patrick; Lubitz, Werner; Herwig, Christoph; Langemann, Timo

    2016-03-24

    The Bacterial Ghost (BG) platform technology evolved from a microbiological expression system incorporating the ϕX174 lysis gene E. E-lysis generates empty but structurally intact cell envelopes (BGs) from Gram-negative bacteria which have been suggested as candidate vaccines, immunotherapeutic agents or drug delivery vehicles. E-lysis is a highly dynamic and complex biological process that puts exceptional demands towards process understanding and control. The development of a both economic and robust fed-batch production process for BGs required a toolset capable of dealing with rapidly changing concentrations of viable biomass during the E-lysis phase. This challenge was addressed using a transfer function combining dielectric spectroscopy and soft-sensor based biomass estimation for monitoring the rapid decline of viable biomass during the E-lysis phase. The transfer function was implemented to a feed-controller, which followed the permittivity signal closely and was capable of maintaining a constant specific substrate uptake rate during lysis phase. With the described toolset, we were able to increase the yield of BG production processes by a factor of 8-10 when compared to currently used batch procedures reaching lysis efficiencies >98%. This provides elevated potentials for commercial application of the Bacterial Ghost platform technology.

  14. EFFECT OF REFINED PETROLEUM PRODUCTS CONTAMINATION ON BACTERIAL POPULATION AND PHYSICOCHEMICAL CHARACTERISTICS OF CULTIVATED AGRICULTURAL SOIL

    Directory of Open Access Journals (Sweden)

    Adewale Sogo Olalemi

    2012-10-01

    Full Text Available An investigation into the effect of refined petroleum products contamination on bacterial population and physicochemical characteristics of cultivated agricultural soil was carried out. The soil samples obtained from the Teaching and Research Farm, Obakekere, Federal University of Technology, Akure, Ondo State were contaminated with varying volumes of petrol, diesel and kerosene. The results revealed higher bacterial populations in uncontaminated soils than contaminated soils. The counts of bacteria ranged from 3.0 × 105 to 5.0 × 105 cfu/g in uncontaminated soils and 1.0 × 105 to 3.0 × 105 cfu/g in contaminated soils. The isolated bacteria were identified as Bacillus subtilis, Flavobacterium lutescens, Micrococcus luteus, Corynebacterium variabilis, Pseudomonas fluorescens. The contamination had no significant effect on pH, potassium, sodium, organic carbon and nitrogen content of the soils, while the moisture, calcium, phosphorus and magnesium content of the contaminated soils were significantly different (P < 0.05 compared with the uncontaminated soils. The ability of Bacillus subtilis, Flavobacterium lutescens, Micrococcus luteus, and Pseudomonas fluorescens to utilize the refined petroleum products suggest that these bacteria had potential to bioremediate petroleum contaminated soils.

  15. Fed-Batch Production of Bacterial Ghosts Using Dielectric Spectroscopy for Dynamic Process Control

    Science.gov (United States)

    Meitz, Andrea; Sagmeister, Patrick; Lubitz, Werner; Herwig, Christoph; Langemann, Timo

    2016-01-01

    The Bacterial Ghost (BG) platform technology evolved from a microbiological expression system incorporating the ϕX174 lysis gene E. E-lysis generates empty but structurally intact cell envelopes (BGs) from Gram-negative bacteria which have been suggested as candidate vaccines, immunotherapeutic agents or drug delivery vehicles. E-lysis is a highly dynamic and complex biological process that puts exceptional demands towards process understanding and control. The development of a both economic and robust fed-batch production process for BGs required a toolset capable of dealing with rapidly changing concentrations of viable biomass during the E-lysis phase. This challenge was addressed using a transfer function combining dielectric spectroscopy and soft-sensor based biomass estimation for monitoring the rapid decline of viable biomass during the E-lysis phase. The transfer function was implemented to a feed-controller, which followed the permittivity signal closely and was capable of maintaining a constant specific substrate uptake rate during lysis phase. With the described toolset, we were able to increase the yield of BG production processes by a factor of 8–10 when compared to currently used batch procedures reaching lysis efficiencies >98%. This provides elevated potentials for commercial application of the Bacterial Ghost platform technology.

  16. Effect of grazers and viruses on bacterial community structure and production in two contrasting trophic lakes

    Directory of Open Access Journals (Sweden)

    Domaizon Isabelle

    2011-04-01

    Full Text Available Abstract Background Over the last 30 years, extensive studies have revealed the crucial roles played by microbes in aquatic ecosystems. It has been shown that bacteria, viruses and protozoan grazers are dominant in terms of abundance and biomass. The frequent interactions between these microbiological compartments are responsible for strong trophic links from dissolved organic matter to higher trophic levels, via heterotrophic bacteria, which form the basis for the important biogeochemical roles of microbial food webs in aquatic ecosystems. To gain a better understanding of the interactions between bacteria, viruses and flagellates in lacustrine ecosystems, we investigated the effect of protistan bacterivory on bacterial abundance, production and structure [determined by 16S rRNA PCR-DGGE], and viral abundance and activity of two lakes of contrasting trophic status. Four experiments were conducted in the oligotrophic Lake Annecy and the mesotrophic Lake Bourget over two seasons (early spring vs. summer using a fractionation approach. In situ dark vs. light incubations were performed to consider the effects of the different treatments in the presence and absence of phototrophic activity. Results The presence of grazers (i.e. Conclusions Our results highlight the importance of a synergistic effect, i.e. the positive influence of grazers on viral activities in sustaining (directly and indirectly bacterial production and affecting composition, in both oligotrophic and mesotrophic lakes.

  17. Fed-Batch Production of Bacterial Ghosts Using Dielectric Spectroscopy for Dynamic Process Control

    Directory of Open Access Journals (Sweden)

    Andrea Meitz

    2016-03-01

    Full Text Available The Bacterial Ghost (BG platform technology evolved from a microbiological expression system incorporating the ϕX174 lysis gene E. E-lysis generates empty but structurally intact cell envelopes (BGs from Gram-negative bacteria which have been suggested as candidate vaccines, immunotherapeutic agents or drug delivery vehicles. E-lysis is a highly dynamic and complex biological process that puts exceptional demands towards process understanding and control. The development of a both economic and robust fed-batch production process for BGs required a toolset capable of dealing with rapidly changing concentrations of viable biomass during the E-lysis phase. This challenge was addressed using a transfer function combining dielectric spectroscopy and soft-sensor based biomass estimation for monitoring the rapid decline of viable biomass during the E-lysis phase. The transfer function was implemented to a feed-controller, which followed the permittivity signal closely and was capable of maintaining a constant specific substrate uptake rate during lysis phase. With the described toolset, we were able to increase the yield of BG production processes by a factor of 8–10 when compared to currently used batch procedures reaching lysis efficiencies >98%. This provides elevated potentials for commercial application of the Bacterial Ghost platform technology.

  18. ATLAS measurements of vector boson production

    CERN Document Server

    Vittori, Camilla; The ATLAS collaboration

    2016-01-01

    Measurements of the Drell­Yan production of W and Z/gamma* bosons at the LHC provide a benchmark of our understanding of perturbative QCD and probe the proton structure in a unique way. The ATLAS collaboration has performed new high precision measurements at center­of­mass energies of 8 and 13 TeV. In the 8 TeV data, we present recent measurements in the di­lepton mass range up to the TeV scale, double­differentially in dilepton mass and rapidity(­separation). The measurements are compared to state­of­the­art calculations at NNLO in QCD and constrain the photon content of the proton. First precise inclusive measurements of W and Z production at 13 TeV are presented. W/Z and W charge ratios profit from a cancellation of experimental uncertainties. The angular distributions of the Drell­Yan lepton pairs around the Z­boson mass peak probe the underlying QCD dynamic of the Z­boson production mechanisms. We present a measurement of the complete set of angular coefficients describing these distributions...

  19. Macrophage activation induced by Brucella DNA suppresses bacterial intracellular replication via enhancing NO production.

    Science.gov (United States)

    Liu, Ning; Wang, Lin; Sun, Changjiang; Yang, Li; Tang, Bin; Sun, Wanchun; Peng, Qisheng

    2015-12-01

    Brucella DNA can be sensed by TLR9 on endosomal membrane and by cytosolic AIM2-inflammasome to induce proinflammatory cytokine production that contributes to partially activate innate immunity. Additionally, Brucella DNA has been identified to be able to act as a major bacterial component to induce type I IFN. However, the role of Brucella DNA in Brucella intracellular growth remains unknown. Here, we showed that stimulation with Brucella DNA promote macrophage activation in TLR9-dependent manner. Activated macrophages can suppresses wild type Brucella intracellular replication at early stage of infection via enhancing NO production. We also reported that activated macrophage promotes bactericidal function of macrophages infected with VirB-deficient Brucella at the early or late stage of infection. This study uncovers a novel function of Brucella DNA, which can help us further elucidate the mechanism of Brucella intracellular survival.

  20. Performance Measurement in Global Product Development

    DEFF Research Database (Denmark)

    Taylor, Thomas Paul; Ahmed-Kristensen, Saeema

    2013-01-01

    An organisation looking to form collaborations across borders is a consequence of an increasingly competitive world market. Recent studies highlighted key challenges and success factors organisation’s face when globalising stages of product development. To optimize performance along these factors...... in global product development. More specifically, results from a survey and interviews highlight a need for further development in current performance measurement frameworks used in product development to facilitate the key factors and metrics in global product development.......An organisation looking to form collaborations across borders is a consequence of an increasingly competitive world market. Recent studies highlighted key challenges and success factors organisation’s face when globalising stages of product development. To optimize performance along these factors...... there is a requirement for the process to be monitored and measured relative to the business strategy of an organisation. It was found that performance measurement is a process that helps achieve sustainable business success, encouraging a learning culture within organisations. To this day, much of the research into how...

  1. Productivity measures and the "new economy"

    OpenAIRE

    John B. Carlson; Schweitzer, Mark E.

    1998-01-01

    The U.S. economy's recent extraordinary performance has led some to claim that trend output growth is accelerating to a much higher rate than any we have experienced in a quarter century; they also maintain that the signs of productivity's acceleration have been masked by measurement problems. The authors, however, find scant evidence to support such claims.

  2. PRODUCTIVITY BENEFITS OF INDUSTRIAL ENERGY EFFICIENCY MEASURES

    Science.gov (United States)

    A journal article by: Ernst Worrell1, John A. Laitner, Michael Ruth, and Hodayah Finman Abstract: We review the relationship between energy efficiency improvement measures and productivity in industry. We review over 70 industrial case studies from widely available published dat...

  3. On ws-convergence of product measures

    NARCIS (Netherlands)

    Balder, E.J.

    2001-01-01

    A canonical redecomposition makes it possible to study the wstopology for measures on a product space by means of recent techniques developed for the narrow topology for transition probabilities Thus a central result is obtained that generalizes both Prohorovs theorem and Komlos theorem it is in ter

  4. Target Product Profile for a Diagnostic Assay to Differentiate between Bacterial and Non-Bacterial Infections and Reduce Antimicrobial Overuse in Resource-Limited Settings: An Expert Consensus.

    Science.gov (United States)

    Dittrich, Sabine; Tadesse, Birkneh Tilahun; Moussy, Francis; Chua, Arlene; Zorzet, Anna; Tängdén, Thomas; Dolinger, David L; Page, Anne-Laure; Crump, John A; D'Acremont, Valerie; Bassat, Quique; Lubell, Yoel; Newton, Paul N; Heinrich, Norbert; Rodwell, Timothy J; González, Iveth J

    2016-01-01

    Acute fever is one of the most common presenting symptoms globally. In order to reduce the empiric use of antimicrobial drugs and improve outcomes, it is essential to improve diagnostic capabilities. In the absence of microbiology facilities in low-income settings, an assay to distinguish bacterial from non-bacterial causes would be a critical first step. To ensure that patient and market needs are met, the requirements of such a test should be specified in a target product profile (TPP). To identify minimal/optimal characteristics for a bacterial vs. non-bacterial fever test, experts from academia and international organizations with expertise in infectious diseases, diagnostic test development, laboratory medicine, global health, and health economics were convened. Proposed TPPs were reviewed by this working group, and consensus characteristics were defined. The working group defined non-severely ill, non-malaria infected children as the target population for the desired assay. To provide access to the most patients, the test should be deployable to community health centers and informal health settings, and staff should require 90% and >80% for sensitivity and specificity, respectively. Other key characteristics, to account for the challenging environment at which the test is targeted, included: i) time-to-result targeted and timely efforts by industry partners and academic institutions.

  5. Target Product Profile for a Diagnostic Assay to Differentiate between Bacterial and Non-Bacterial Infections and Reduce Antimicrobial Overuse in Resource-Limited Settings: An Expert Consensus.

    Science.gov (United States)

    Dittrich, Sabine; Tadesse, Birkneh Tilahun; Moussy, Francis; Chua, Arlene; Zorzet, Anna; Tängdén, Thomas; Dolinger, David L; Page, Anne-Laure; Crump, John A; D'Acremont, Valerie; Bassat, Quique; Lubell, Yoel; Newton, Paul N; Heinrich, Norbert; Rodwell, Timothy J; González, Iveth J

    2016-01-01

    Acute fever is one of the most common presenting symptoms globally. In order to reduce the empiric use of antimicrobial drugs and improve outcomes, it is essential to improve diagnostic capabilities. In the absence of microbiology facilities in low-income settings, an assay to distinguish bacterial from non-bacterial causes would be a critical first step. To ensure that patient and market needs are met, the requirements of such a test should be specified in a target product profile (TPP). To identify minimal/optimal characteristics for a bacterial vs. non-bacterial fever test, experts from academia and international organizations with expertise in infectious diseases, diagnostic test development, laboratory medicine, global health, and health economics were convened. Proposed TPPs were reviewed by this working group, and consensus characteristics were defined. The working group defined non-severely ill, non-malaria infected children as the target population for the desired assay. To provide access to the most patients, the test should be deployable to community health centers and informal health settings, and staff should require 90% and >80% for sensitivity and specificity, respectively. Other key characteristics, to account for the challenging environment at which the test is targeted, included: i) time-to-result development, and enable targeted and timely efforts by industry partners and academic institutions. PMID:27559728

  6. Measurement of radioactivity in volcanic products

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Jun

    1988-10-01

    Radioactivity in volcanic products was measured for obtaining new knowledge about volcano. A distribution map of /sup 2//sup 2//sup 8/Ra//sup 2//sup 2//sup 6/Ra in the volcanic products of Japanese Islands volcanic front was prepared. From the map, it was understood that only Izu-Mariana Arc was different from other series of vocanos. Concerning Volcano Sakurajima, /sup 2//sup 2//sup 2/Rn//sup 2//sup 2//sup 0/Rn ratio in the pumice produced by the eruption was measured for studying its change with days after creation. Regarding the lava of Miyake Island, change of /sup 2//sup 1//sup 4/Bi with time was measured. 3 figures.

  7. Diel variability of heterotrophic bacterial production and UV doses in the South East Pacific

    Directory of Open Access Journals (Sweden)

    F. Van Wambeke

    2008-01-01

    Full Text Available Diel variability of heterotrophic bacterial production (BP was investigated in the South East Pacific from October to December 2004 during the BIOSOPE cruise. Three sites differing by their trophic status were studied: Marquesas Islands (MAR; 08° S, 141° W, the centre of the South Pacific Gyre (SPG (GYR; 26° S, 114° W and the eastern part of the SPG (EGY; 32° S, 91° W. At the three sites, diel variability of BP ranged from 17 to 40% and from 13 to 22% for volumetric surface (5 m and integrated (to Ze and Zm data, respectively. The main feature we observed was at 5 m, an abrupt increase (×2 to ×4 in leucine activity during the afternoon-sunset period (12:00–18:00 at the site MAR and 15:00–21:00 at the site GYR and lowest activities recorded between 10:00 and 14:00. To assess the potential influence of solar ultraviolet radiation (UVR: 280–400 nm on this BP diel variability, we determined, from in situ optical measurements, the mean tri-hourly ultraviolet B (UVB, 305 nm and ultraviolet A (UVA, 380 nm doses (irradiances integrated over time within the mixed layer (Hm(UVB and Hm(UVA, respectively. The wavelengths 305 nm and 380 nm were used as biologically effective wavelengths for the induction of DNA damages (cyclobutane pyrimidine dimers: CPDs and photoenzymatic repairs (PERs, respectively. In the SPG, daily Hm(UVB and Hm(UVA were 0.6 and 14 kJ m−2 nm−1, respectively. The latter were probably the highest daily doses ever measured in the marine environment. The Hm(UVB/Hm(UVA ratio (Q increased by 58, 117 and 46% from 06:00–09:00 to 12:00–15:00, and decreased by 36, 26 and 16% from 12:00–15:00 to 15:00–18:00 at the sites MAR, GYR and EGY, respectively. The relationship between Q and BP suggested a significant influence of UVR on the diel

  8. Construction of force measuring optical tweezers instrumentation and investigations of biophysical properties of bacterial adhesion organelles

    CERN Document Server

    Andersson, Magnus

    2015-01-01

    Optical tweezers are a technique in which microscopic-sized particles, including living cells and bacteria, can be non-intrusively trapped with high accuracy solely using focused light. The technique has therefore become a powerful tool in the field of biophysics. Optical tweezers thereby provide outstanding manipulation possibilities of cells as well as semi-transparent materials, both non-invasively and non-destructively, in biological systems. In addition, optical tweezers can measure minute forces (< 10-12 N), probe molecular interactions and their energy landscapes, and apply both static and dynamic forces in biological systems in a controlled manner. The assessment of intermolecular forces with force measuring optical tweezers, and thereby the biomechanical structure of biological objects, has therefore considerably facilitated our understanding of interactions and structures of biological systems. Adhesive bacterial organelles, so called pili, mediate adhesion to host cells and are therefore crucial...

  9. ATLAS measurement of Electroweak Vector Boson production

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00453010; The ATLAS collaboration

    2016-01-01

    Measurements of the Drell-Yan production of W and Z/γ∗ bosons at the LHC provide a benchmark of our un- derstanding of perturbative QCD and probe the proton structure in a unique way. The ATLAS collaboration has performed new high precision measurements of the double differential cross-sections in dilepton mass and rapidity. The measurements are compared to state of calculations at NNLO in QCD and constrain the photon content of the proton. The angular distributions of the Drell-Yan lepton pairs around the Z-boson mass peak probe the underlying QCD dynamic of the Z-boson production mechanisms. The complete set of angular coefficients describing these dis- tributions is presented and compare to theoretical predictions highlighting different approaches of the QCD and EW modelling. First precise inclusive measurements of W and Z production at 13 TeV are presented. W/Z and W+/W− ratios profit from a cancellation of experimental uncertainties.

  10. Production of bacterial cellulose with controlled deuterium-hydrogen substitution for neutron scattering studies.

    Science.gov (United States)

    O'Neill, Hugh; Shah, Riddhi; Evans, Barbara R; He, Junhong; Pingali, Sai Venkatesh; Chundawat, Shishir P S; Jones, A Daniel; Langan, Paul; Davison, Brian H; Urban, Volker

    2015-01-01

    Isotopic enrichment of biomacromolecules is a widely used technique that enables the investigation of the structural and dynamic properties to provide information not accessible with natural abundance isotopic composition. This study reports an approach for deuterium incorporation into bacterial cellulose. A media formulation for growth of Acetobacter xylinus subsp. sucrofermentans and Gluconacetobacter hansenii was formulated that supports cellulose production in deuterium (D) oxide. The level of D incorporation can be varied by altering the ratio of deuterated and protiated glycerol used during cell growth in the D2O-based growth medium. Spectroscopic analysis and mass spectrometry show that the level of deuterium incorporation is high (>90%) for the perdeuterated form of bacterial cellulose. The small-angle neutron scattering profiles of the cellulose with different amounts of D incorporation are all similar indicating that there are no structural changes in the cellulose due to substitution of deuterium for hydrogen. In addition, by varying the amount of deuterated glycerol in the media it was possible to vary the scattering length density of the deuterated cellulose. The ability to control deuterium content of cellulose extends the range of experiments using techniques such as neutron scattering to reveal information about the structure and dynamics of cellulose, and its interactions with other biomacromolecules as well as synthetic polymers used for development of composite materials. PMID:26577730

  11. Bacterial community structure and variation in a full-scale seawater desalination plant for drinking water production

    KAUST Repository

    Belila, A.

    2016-02-18

    Microbial processes inevitably play a role in membrane-based desalination plants, mainly recognized as membrane biofouling. We assessed the bacterial community structure and diversity during different treatment steps in a full-scale seawater desalination plant producing 40,000 m3/d of drinking water. Water samples were taken over the full treatment train consisting of chlorination, spruce media and cartridge filters, de-chlorination, first and second pass reverse osmosis (RO) membranes and final chlorine dosage for drinking water distribution. The water samples were analyzed for water quality parameters (total bacterial cell number, total organic carbon, conductivity, pH, etc.) and microbial community composition by 16S rRNA gene pyrosequencing. The planktonic microbial community was dominated by Proteobacteria (48.6%) followed by Bacteroidetes (15%), Firmicutes (9.3%) and Cyanobacteria (4.9%). During the pretreatment step, the spruce media filter did not impact the bacterial community composition dominated by Proteobacteria. In contrast, the RO and final chlorination treatment steps reduced the Proteobacterial relative abundance in the produced water where Firmicutes constituted the most dominant bacterial group. Shannon and Chao1 diversity indices showed that bacterial species richness and diversity decreased during the seawater desalination process. The two-stage RO filtration strongly reduced the water conductivity (>99%), TOC concentration (98.5%) and total bacterial cell number (>99%), albeit some bacterial DNA was found in the water after RO filtration. About 0.25% of the total bacterial operational taxonomic units (OTUs) were present in all stages of the desalination plant: the seawater, the RO permeates and the chlorinated drinking water, suggesting that these bacterial strains can survive in different environments such as high/low salt concentration and with/without residual disinfectant. These bacterial strains were not caused by contamination during

  12. Bacterial community structure and variation in a full-scale seawater desalination plant for drinking water production.

    Science.gov (United States)

    Belila, A; El-Chakhtoura, J; Otaibi, N; Muyzer, G; Gonzalez-Gil, G; Saikaly, P E; van Loosdrecht, M C M; Vrouwenvelder, J S

    2016-05-01

    Microbial processes inevitably play a role in membrane-based desalination plants, mainly recognized as membrane biofouling. We assessed the bacterial community structure and diversity during different treatment steps in a full-scale seawater desalination plant producing 40,000 m(3)/d of drinking water. Water samples were taken over the full treatment train consisting of chlorination, spruce media and cartridge filters, de-chlorination, first and second pass reverse osmosis (RO) membranes and final chlorine dosage for drinking water distribution. The water samples were analyzed for water quality parameters (total bacterial cell number, total organic carbon, conductivity, pH, etc.) and microbial community composition by 16S rRNA gene pyrosequencing. The planktonic microbial community was dominated by Proteobacteria (48.6%) followed by Bacteroidetes (15%), Firmicutes (9.3%) and Cyanobacteria (4.9%). During the pretreatment step, the spruce media filter did not impact the bacterial community composition dominated by Proteobacteria. In contrast, the RO and final chlorination treatment steps reduced the Proteobacterial relative abundance in the produced water where Firmicutes constituted the most dominant bacterial group. Shannon and Chao1 diversity indices showed that bacterial species richness and diversity decreased during the seawater desalination process. The two-stage RO filtration strongly reduced the water conductivity (>99%), TOC concentration (98.5%) and total bacterial cell number (>99%), albeit some bacterial DNA was found in the water after RO filtration. About 0.25% of the total bacterial operational taxonomic units (OTUs) were present in all stages of the desalination plant: the seawater, the RO permeates and the chlorinated drinking water, suggesting that these bacterial strains can survive in different environments such as high/low salt concentration and with/without residual disinfectant. These bacterial strains were not caused by contamination during

  13. Bacterial community structure and variation in a full-scale seawater desalination plant for drinking water production.

    Science.gov (United States)

    Belila, A; El-Chakhtoura, J; Otaibi, N; Muyzer, G; Gonzalez-Gil, G; Saikaly, P E; van Loosdrecht, M C M; Vrouwenvelder, J S

    2016-05-01

    Microbial processes inevitably play a role in membrane-based desalination plants, mainly recognized as membrane biofouling. We assessed the bacterial community structure and diversity during different treatment steps in a full-scale seawater desalination plant producing 40,000 m(3)/d of drinking water. Water samples were taken over the full treatment train consisting of chlorination, spruce media and cartridge filters, de-chlorination, first and second pass reverse osmosis (RO) membranes and final chlorine dosage for drinking water distribution. The water samples were analyzed for water quality parameters (total bacterial cell number, total organic carbon, conductivity, pH, etc.) and microbial community composition by 16S rRNA gene pyrosequencing. The planktonic microbial community was dominated by Proteobacteria (48.6%) followed by Bacteroidetes (15%), Firmicutes (9.3%) and Cyanobacteria (4.9%). During the pretreatment step, the spruce media filter did not impact the bacterial community composition dominated by Proteobacteria. In contrast, the RO and final chlorination treatment steps reduced the Proteobacterial relative abundance in the produced water where Firmicutes constituted the most dominant bacterial group. Shannon and Chao1 diversity indices showed that bacterial species richness and diversity decreased during the seawater desalination process. The two-stage RO filtration strongly reduced the water conductivity (>99%), TOC concentration (98.5%) and total bacterial cell number (>99%), albeit some bacterial DNA was found in the water after RO filtration. About 0.25% of the total bacterial operational taxonomic units (OTUs) were present in all stages of the desalination plant: the seawater, the RO permeates and the chlorinated drinking water, suggesting that these bacterial strains can survive in different environments such as high/low salt concentration and with/without residual disinfectant. These bacterial strains were not caused by contamination during

  14. Beneficial Effect of Acetic Acid on the Xylose Utilization and Bacterial Cellulose Production by Gluconacetobacter xylinus.

    Science.gov (United States)

    Yang, Xiao-Yan; Huang, Chao; Guo, Hai-Jun; Xiong, Lian; Luo, Jun; Wang, Bo; Chen, Xue-Fang; Lin, Xiao-Qing; Chen, Xin-De

    2014-09-01

    In this work, acetic acid was found as one promising substrate to improve xylose utilization by Gluconacetobacter xylinus CH001. Also, with the help of adding acetic acid into medium, the bacterial cellulose (BC) production by G. xylinus was increased significantly. In the medium containing 3 g l(-1) acetic acid, the optimal xylose concentration for BC production was 20 g l(-1). In the medium containing 20 g l(-1) xylose, the xylose utilization and BC production by G. xylinus were stimulated by acetic acid within certain concentration. The highest BC yield (1.35 ± 0.06 g l(-1)) was obtained in the medium containing 20 g l(-1) xylose and 3 g l(-1) acetic acid after 14 days. This value was 6.17-fold higher than the yield (0.21 ± 0.01 g l(-1)) in the medium only containing 20 g l(-1) xylose. The results analyzed by FE-SEM, FTIR, and XRD showed that acetic acid affected little on the microscopic morphology and physicochemical characteristics of BC. Base on the phenomenon observed, lignocellulosic acid hydrolysates (xylose and acetic acid are main carbon sources present in it) could be considered as one potential substrate for BC production.

  15. Optimization of bacterial cellulose production by Gluconacetobacter xylinus using carob and haricot bean.

    Science.gov (United States)

    Bilgi, Eyup; Bayir, Ece; Sendemir-Urkmez, Aylin; Hames, E Esin

    2016-09-01

    Bacterial cellulose (BC) can be used in medical, biomedical, electronic, food, and paper industries because of its unique properties distinguishing it from plant cellulose. BC production was statistically optimized by Gluconacetobacter xylinus strain using carob and haricot bean (CHb) medium. Eight parameters were evaluated by Plackett-Burman Design and significant three parameters were optimized by Central Composite Design. Optimal conditions for production of BC in static culture were found as: 2.5g/L carbon source, 2.75g/L protein source, 9.3% inoculum ratio, 1.15g/L citric acid, 2.7g/L Na2HPO4, 30°C incubation temperature, 5.5 initial pH, and 9days of incubation. This study reveals that BC production can be carried out using carob and haricot bean extracts as carbon and nitrogen sources, and CHb medium has higher buffering capacity compared to Hestrin and Schramm media. Model obtained from this study is used to predict and optimize BC production yield using CHb medium.

  16. Optimization of bacterial cellulose production by Gluconacetobacter xylinus using carob and haricot bean.

    Science.gov (United States)

    Bilgi, Eyup; Bayir, Ece; Sendemir-Urkmez, Aylin; Hames, E Esin

    2016-09-01

    Bacterial cellulose (BC) can be used in medical, biomedical, electronic, food, and paper industries because of its unique properties distinguishing it from plant cellulose. BC production was statistically optimized by Gluconacetobacter xylinus strain using carob and haricot bean (CHb) medium. Eight parameters were evaluated by Plackett-Burman Design and significant three parameters were optimized by Central Composite Design. Optimal conditions for production of BC in static culture were found as: 2.5g/L carbon source, 2.75g/L protein source, 9.3% inoculum ratio, 1.15g/L citric acid, 2.7g/L Na2HPO4, 30°C incubation temperature, 5.5 initial pH, and 9days of incubation. This study reveals that BC production can be carried out using carob and haricot bean extracts as carbon and nitrogen sources, and CHb medium has higher buffering capacity compared to Hestrin and Schramm media. Model obtained from this study is used to predict and optimize BC production yield using CHb medium. PMID:26906562

  17. Enhanced production of bacterial cellulose by using a biofilm reactor and its material property analysis

    Directory of Open Access Journals (Sweden)

    Demirci Ali

    2009-07-01

    Full Text Available Abstract Bacterial cellulose has been used in the food industry for applications such as low-calorie desserts, salads, and fabricated foods. It has also been used in the paper manufacturing industry to enhance paper strength, the electronics industry in acoustic diaphragms for audio speakers, the pharmaceutical industry as filtration membranes, and in the medical field as wound dressing and artificial skin material. In this study, different types of plastic composite support (PCS were implemented separately within a fermentation medium in order to enhance bacterial cellulose (BC production by Acetobacter xylinum. The optimal composition of nutritious compounds in PCS was chosen based on the amount of BC produced. The selected PCS was implemented within a bioreactor to examine the effects on BC production in a batch fermentation. The produced BC was analyzed using X-ray diffraction (XRD, field emission scanning electron microscopy (FESEM, thermogravimetric analysis (TGA, and dynamic mechanical analysis (DMA. Among thirteen types of PCS, the type SFYR+ was selected as solid support for BC production by A. xylinum in a batch biofilm reactor due to its high nitrogen content, moderate nitrogen leaching rate, and sufficient biomass attached on PCS. The PCS biofilm reactor yielded BC production (7.05 g/L that was 2.5-fold greater than the control (2.82 g/L. The XRD results indicated that the PCS-grown BC exhibited higher crystallinity (93% and similar crystal size (5.2 nm to the control. FESEM results showed the attachment of A. xylinum on PCS, producing an interweaving BC product. TGA results demonstrated that PCS-grown BC had about 95% water retention ability, which was lower than BC produced within suspended-cell reactor. PCS-grown BC also exhibited higher Tmax compared to the control. Finally, DMA results showed that BC from the PCS biofilm reactor increased its mechanical property values, i.e., stress at break and Young's modulus when compared to

  18. Muramic Acid Measurements for Bacterial Investigations in Marine Environments by High-Pressure Liquid Chromatography

    Science.gov (United States)

    Mimura, Toru; Romano, Jean-Claude

    1985-01-01

    Muramic acid, a constituent of procaryotic cell walls, was assayed by high-pressure liquid chromatography in samples from several marine environments (water column, surface microlayer, and sediment) and a bacterial culture. It is used as a microbial biomass indicator. The method gave a good separation of muramic acid from interfering compounds with satisfactory reproducibility. A pseudomonad culture had a muramic acid content of 4.7 × 10−10 to 5.3 × 10−10 μg per cell during growth. In natural water samples, highly significant relationships were found between muramic acid concentrations and bacterial numbers for populations of 108 to 1011 cells per liter. The muramic acid content in natural marine water decreased from 5.3 × 10−10 to 1.6 × 10−10 μg per cell with increasing depth. In coastal sediments exposed to sewage pollution, concentrations of muramic acid, ATP, organic carbon, and total amino acids displayed a parallel decrease with increasing distance from the sewage outlet. Advantages of muramic acid measurement by high-pressure liquid chromatography are its high sensitivity and reduction of preparation steps, allowing a short time analysis. PMID:16346848

  19. Light scattering measurement of sodium polyacrylate products

    Science.gov (United States)

    Lama, Nisha; Norwood, David; Boone, Steven; Massie-Boyer, Valerie

    2015-03-01

    In the presentation, we will describe the use of a multi-detector HPLC incorporating the DAWN EOS multi-angle laser light scattering (MALLS) detector to measure the properties such as molecular weight, RMS radius, contour and persistence length and polydispersity of sodium polyacrylate products. The samples of sodium polyacrylate are used in various industries as thickening agents, coating dispersants, artificial snow, laundry detergent and disposable diapers. Data and results obtained from the experiment will be presented.

  20. Prospecting for new bacterial metabolites: a glossary of approaches for inducing, activating and upregulating the biosynthesis of bacterial cryptic or silent natural products.

    Science.gov (United States)

    Zarins-Tutt, Joseph Scott; Barberi, Tania Triscari; Gao, Hong; Mearns-Spragg, Andrew; Zhang, Lixin; Newman, David J; Goss, Rebecca Jane Miriam

    2016-01-01

    Covering: up to 2015. Over the centuries, microbial secondary metabolites have played a central role in the treatment of human diseases and have revolutionised the pharmaceutical industry. With the increasing number of sequenced microbial genomes revealing a plethora of novel biosynthetic genes, natural product drug discovery is entering an exciting second golden age. Here, we provide a concise overview as an introductory guide to the main methods employed to unlock or up-regulate these so called 'cryptic', 'silent' and 'orphan' gene clusters, and increase the production of the encoded natural product. With a predominant focus on bacterial natural products we will discuss the importance of the bioinformatics approach for genome mining, the use of first different and simple culturing techniques and then the application of genetic engineering to unlock the microbial treasure trove. PMID:26538321

  1. Bacterial production in Guanabara Bay (Rio de Janeiro, Brazil evaluated by ³H-leucine incorporation

    Directory of Open Access Journals (Sweden)

    Alessandra M. Gonzalez

    2000-01-01

    Full Text Available The aim of this work was to evaluate the necessary ³H-leucine concentration to estimate bacterial production in Guanabara Bay through saturation curves. A second aim was to collect preliminary data of bacterial production in two distinct sites corresponding to different water qualities: Urca inlet and Governador Island. Saturation curves were made with water samples taken at the main circulation channel of the bay, Paquetá Island, and the two sites mentioned before. The ³H-leucine curves showed similar pattern for all studied areas, indicating the ideal isotope concentration to be 10 nM. Bacterial biomass production ranged from 0.40 to 4.53 µgC L-1 h-1 in Urca and from 3.86 to 73.72 µgC L-1 h-1 in Governador Island indicating the relationship between nutrients and organic matter supply and bacterial productivity. This work is an important reference for studies on trophodynamics, biogeochemical cycles and modelling in Guanabara Bay.O objetivo desse trabalho foi realizar curvas de saturação a fim de otimizar a concentração de ³H-leucina necessária para avaliar produção bacteriana na Baía de Guanabara. Objetivou-se ainda a aquisição de dados preliminares de produção bacteriana em dois locais distintos em termos de qualidade de água : enseada da Urca e Ilha do Governador. As amostras para as curvas foram obtidas na região do Canal Central e na Ilha de Paquetá, além dos dois locais de coleta citados acima. Seguiu-se a metodologia descrita por Kirchman et al. (1985 e modificada por Smith & Azam (1992. As curvas de ³H-leucina mostraram um padrão semelhante para todas as áreas estudadas, indicando a concentração ótima de isótopo de 10 nM. A produção de biomassa bacteriana variou de 0,40 a 4,53 µgC L-1 h-1 na Urca e de 3,86 a 73,72 µgC L-1 h-1 na Ilha do Governador confirmando a relação entre a disponibilidade de nutrientes e matéria orgânica e o aumento da produtividade bacteriana. Essas análises poderão ser

  2. Identification and characterization of a bacterial hyaluronidase and its production in recombinant form.

    Science.gov (United States)

    Messina, Luciano; Gavira, Jose A; Pernagallo, Salvatore; Unciti-Broceta, Juan D; Sanchez Martin, Rosario M; Diaz-Mochon, Juan J; Vaccaro, Susanna; Conejero-Muriel, Mayte; Pineda-Molina, Estela; Caruso, Salvatore; Musumeci, Luca; Di Pasquale, Roberta; Pontillo, Angela; Sincinelli, Francesca; Pavan, Mauro; Secchieri, Cynthia

    2016-07-01

    Hyaluronidases (Hyals) are broadly used in medical applications to facilitate the dispersion and/or absorption of fluids or medications. This study reports the isolation, cloning, and industrial-scale recombinant production, purification and full characterization, including X-ray structure determination at 1.45 Å, of an extracellular Hyal from the nonpathogenic bacterium Streptomyces koganeiensis. The recombinant S. koganeiensis Hyal (rHyal_Sk) has a novel bacterial catalytic domain with high enzymatic activity, compared with commercially available Hyals, and is more thermostable and presents higher proteolytic resistance, with activity over a broad pH range. Moreover, rHyal_Sk exhibits remarkable substrate specificity for hyaluronic acid (HA) and poses no risk of animal cross-infection. PMID:27311405

  3. Differential response of planktonic primary, bacterial, and dimethylsulfide production rates to vertically-moving and static incubations in upper mixed-layer summer sea waters

    Science.gov (United States)

    Galí, M.; Simó, R.; Pérez, G. L.; Ruiz-González, C.; Sarmento, H.; Royer, S.-J.; Fuentes-Lema, A.; Gasol, J. M.

    2013-05-01

    Microbial plankton experience fluctuations in total solar irradiance and in its spectral composition as they are vertically moved by turbulence in the oceanic upper mixed layer (UML). The fact that the light exposure is not static but dynamic may have important consequences for biogeochemical processes and ocean-atmosphere fluxes. However, most biogeochemical processes other than primary production, like bacterial production or dimethylsulfide (DMS) production, are seldom measured in sunlight and even less often in dynamic light fields. We conducted four experiments in oligotrophic summer stratified Mediterranean waters, where a sample from the UML was incubated in ultraviolet (UV)-transparent bottles at three fixed depths within the UML and on a vertically-moving basket across the same depth range. We assessed the response of the phyto- and bacterioplankton community with physiological indicators based on flow cytometry singe-cell measurements, Fast Repetition Rate fluorometry (FRRf), phytoplankton pigment concentrations and particulate light absorption. Dynamic light exposure caused a disruption of the photoinhibition and photoacclimation processes associated to ultraviolet radiation (UVR), which slightly alleviated bacterial photoinhibition but did not favor primary production. Gross DMS production (GPDMS) decreased sharply with depth in parallel to shortwave UVR, and displayed a dose-dependent response that mixing did not significantly disrupt. To our knowledge, we provide the first measurements of GPDMS under in situ UV-inclusive optical conditions.

  4. Differential response of planktonic primary, bacterial, and dimethylsulfide production rates to static vs. dynamic light exposure in upper mixed-layer summer sea waters

    Science.gov (United States)

    Galí, M.; Simó, R.; Pérez, G. L.; Ruiz-González, C.; Sarmento, H.; Royer, S.-J.; Fuentes-Lema, A.; Gasol, J. M.

    2013-12-01

    Microbial plankton experience short-term fluctuations in total solar irradiance and in its spectral composition as they are vertically moved by turbulence in the oceanic upper mixed layer (UML). The fact that the light exposure is not static but dynamic may have important consequences for biogeochemical processes and ocean-atmosphere fluxes. However, most biogeochemical processes other than primary production, like bacterial production or dimethylsulfide (DMS) production, are seldom measured in sunlight and even less often in dynamic light fields. We conducted four experiments in oligotrophic summer stratified Mediterranean waters, where a sample from the UML was incubated in ultraviolet (UV)-transparent bottles at three fixed depths within the UML and on a vertically moving basket across the same depth range. We assessed the response of the phyto- and bacterioplankton community with physiological indicators based on flow cytometry singe-cell measurements, fast repetition rate fluorometry (FRRf), phytoplankton pigment concentrations and particulate light absorption. Dynamic light exposure caused a subtle disruption of the photoinhibition and photoacclimation processes associated with ultraviolet radiation (UVR), which slightly alleviated bacterial photoinhibition but did not favor primary production. Gross DMS production (GPDMS) decreased sharply with depth in parallel to shortwave UVR, and displayed a dose-dependent response that mixing did not significantly disrupt. To our knowledge, we provide the first measurements of GPDMS under in situ UV-inclusive optical conditions.

  5. Food additives reduce lactic acid bacterial growth in culture medium and in meat products, increasing product shelf life

    Directory of Open Access Journals (Sweden)

    Cleonice Mendes Pereira Sarmento

    2015-12-01

    Full Text Available The uncontrolled growth of lactic acid bacteria (LAB in meat and meat products leads to product spoilage, and thus shortens product shelf life. Although food additives are known to decrease LAB growth, this effect has not been analyzed in detail. Here, a detailed analysis was performed of the effects of sodium chloride, sodium polyphosphate, sodium lactate, sodium nitrite/nitrate, and garlic on the growth of the Lactobacillus plantarum in culture medium. The results were used to design and test experimental formulations of meat products. Initially, the effect of food additives on L. plantarum was evaluated using a Fractional Factorial Design (FFD, followed by a Central Composite Rotatable Design (CCRD. The Modified Gompertz Model was adjusted to the growth curves to determine the Kinetic parameters of bacterial growth (logarithmic increase in the population, specific growth rate, and lag phase extension. Higher sodium lactate and sodium chloride levels had a negative impact on L. plantarum growth parameters (p?0.05. Therefore, we designed experimental formulations of mortadella and smoked pork sausages containing 4% sodium lactate (w w-1 and 2.4-3.5% sodium chloride (w w-1, and determined LAB growth from samples of stored products produced according to these formulations, in order to determine product shelf life. There was an increased lag phase of LAB growth for most experimental formulations. Also, the experimental smoked pork sausages had a longer shelf life, which was increased by at least 22 days, suggesting that the proposed formulation, with higher than standard lactate concentration, increased the product’s shelf life.

  6. Bacterial diversity and mycotoxin reduction during maize fermentation (steeping for ogi production

    Directory of Open Access Journals (Sweden)

    Chiamaka A Okeke

    2015-12-01

    Full Text Available Bacterial diversity and community structure of two maize varieties (white and yellow during fermentation/steeping for ogi production, and the influence of spontaneous fermentation on mycotoxin reduction in the gruel were studied. A total of 142 bacterial isolates obtained at 24–96h intervals were preliminarily identified by conventional microbiological methods while 60 selected isolates were clustered into 39 OTUs consisting of 15 species, 10 genera and 3 phyla by 16S rRNA sequence analysis. Lactic acid bacteria constituted about 63% of all isolated bacteria and the genus Pediococcus dominated (white maize = 84.8%; yellow maize = 74.4%. Pediococcus acidilactici and Lactobacillus paraplantarum were found at all steeping intervals of white and yellow maize, respectively, while P. claussenii was present only at the climax stage of steeping white maize. In both maize varieties, P. pentosaceus was found at 24–72h. Mycotoxin concentrations (µg/kg in the unsteeped grains were: white maize (aflatoxin B1 = 0.60; citrinin = 85.8; cyclopiazonic acid = 23.5; fumonisins (B1/B2/B3 = 68.4–483; zearalenone = 3.3 and yellow maize (aflatoxins (B1/B2/M1 = 22.7–513; citrinin = 16,800; cyclopiazonic acid = 247; fumonisins (B1/B2/B3 = 252–1,586; zearalenone = 205. Mycotoxins in both maize varieties were significantly (p<0.05 reduced across steeping periods. This study reports for the first time: (a the association of L. paraplantarum, P. acidilactici and P. claussenii with ogi production from maize, (b citrinin occurrence in Nigerian maize and ogi, and (c aflatoxin M1, citrinin and cyclopiazonic acid degradation/loss due to fermentation in traditional cereal-based fermented food.

  7. Bacterial indicator of agricultural management for soil under no-till crop production.

    Directory of Open Access Journals (Sweden)

    Eva L M Figuerola

    Full Text Available The rise in the world demand for food poses a challenge to our ability to sustain soil fertility and sustainability. The increasing use of no-till agriculture, adopted in many areas of the world as an alternative to conventional farming, may contribute to reduce the erosion of soils and the increase in the soil carbon pool. However, the advantages of no-till agriculture are jeopardized when its use is linked to the expansion of crop monoculture. The aim of this study was to survey bacterial communities to find indicators of soil quality related to contrasting agriculture management in soils under no-till farming. Four sites in production agriculture, with different soil properties, situated across a west-east transect in the most productive region in the Argentinean pampas, were taken as the basis for replication. Working definitions of Good no-till Agricultural Practices (GAP and Poor no-till Agricultural Practices (PAP were adopted for two distinct scenarios in terms of crop rotation, fertilization, agrochemicals use and pest control. Non-cultivated soils nearby the agricultural sites were taken as additional control treatments. Tag-encoded pyrosequencing was used to deeply sample the 16S rRNA gene from bacteria residing in soils corresponding to the three treatments at the four locations. Although bacterial communities as a whole appeared to be structured chiefly by a marked biogeographic provincialism, the distribution of a few taxa was shaped as well by environmental conditions related to agricultural management practices. A statistically supported approach was used to define candidates for management-indicator organisms, subsequently validated using quantitative PCR. We suggest that the ratio between the normalized abundance of a selected group of bacteria within the GP1 group of the phylum Acidobacteria and the genus Rubellimicrobium of the Alphaproteobacteria may serve as a potential management-indicator to discriminate between

  8. Production of bacterial cellulose using different carbon sources and culture media.

    Science.gov (United States)

    Mohammadkazemi, Faranak; Azin, Mehrdad; Ashori, Alireza

    2015-03-01

    In this work, the effects of carbon sources and culture media on the production and structural properties of bacterial cellulose (BC) have been studied. BC nanofibers were synthesized using Gluconacetobacter xylinus strain PTCC 1734. Media used were Hestrin-Schramm (H), Yamanaka (Y), and Zhou (Z). Five different carbon sources, namely date syrup, glucose, mannitol, sucrose, and food-grade sucrose were used in these media. All the produced BC pellicles were characterized in terms of dry weight production, biomass yield, thermal stability, crystallinity and morphology by thermogravimetric analysis (TGA), x-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM). The obtained results showed that mannitol lead to the highest yield, followed by sucrose. The highest production efficiency of mannitol might be due to the nitrogen source, which plays an important role. The maximum improvement on the thermal stability of the composites was achieved when mannitol was used in H medium. In addition, the crystallinity was higher in BC formed in H medium compared to other media. FE-SEM micrographs illustrated that the BC pellicles, synthesized in the culture media H and Z, were stable, unlike those in medium Y that were unstable. The micrographs of BC produced in media containing mannitol and sucrose provided evidence of the strong interfacial adhesion between the BC fibers without noticeable aggregates.

  9. Utilization of corncob acid hydrolysate for bacterial cellulose production by Gluconacetobacter xylinus.

    Science.gov (United States)

    Huang, Chao; Yang, Xiao-Yan; Xiong, Lian; Guo, Hai-Jun; Luo, Jun; Wang, Bo; Zhang, Hai-Rong; Lin, Xiao-Qing; Chen, Xin-De

    2015-02-01

    In this study, corncob acid hydrolysate was used as a substrate for bacterial cellulose (BC) production by Gluconacetobacter xylinus. After 2 weeks' static fermentation, a BC yield of 4 g/L could be obtained. Both effects of medium composition and fermentation condition on the BC production were evaluated. Most extra substrates (carbon and nitrogen sources) except mannitol, butyric acid, and levulinic acid showed no effect on the improvement of BC yield. Fermentation condition including fermentation mode, inoculation concentration, and initial pH showed certain influence on the BC yield and thus should be well controlled. The analysis by field emission scanning electron microscope (FE-SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) showed that the BC sample had obvious nano-network structure, clear functional groups that were found in cellulose, and relatively high crystallinity and crystallinity index value. Moreover, the BC sample had great water-holding capacity. Overall, corncob acid hydrolysate could be one promising substrate for BC production.

  10. Production of bacterial cellulose by Gluconacetobacter hansenii UAC09 using coffee cherry husk.

    Science.gov (United States)

    Rani, M Usha; Appaiah, K A Anu

    2013-08-01

    The work is aimed to investigate the suitability of underutilized coffee cherry husk (CCH) for the production and optimization of bacterial cellulose (BC) by Gluconacetobacter hansenii UAC09 and to study the physico-mechanical properties of BC films. CCH extract was used as a carbon source in various concentrations along with other nutritional components such as nitrogen (corn steep liquor, urea) and additives (ethyl alcohol, acetic acid). Concentration of CCH extract at 1:1 (w/v) along with 8% (v/v) corn steep liquor, 0.2% (w/v) urea, combination of 1.5% ethyl alcohol and 1.0% (v/v) acetic acid resulted in the production of 5.6-8.2 g/L of BC. BC had tensile strength varying between 28.5 and 42.4 MPa. BC produced with CCH and Hestrin and Schramm (HS) media did not differ in structure as analyzed by FT-IR. Scanning electron microscopic studies indicated BC to contain reticulated network of fine fibers. Under optimized condition, based on the other additives, CCH produced more than three folds yield of BC (5.6-8.2 g/L) than control medium (1.5 g/L). This is the first report on the use of CCH for the production of BC and paved way for the utilization of organic wastes with pectin and high polyphenol content.

  11. Metabolic Investigation in Gluconacetobacter xylinus and Its Bacterial Cellulose Production under a Direct Current Electric Field.

    Science.gov (United States)

    Liu, Miao; Zhong, Cheng; Zhang, Yu Ming; Xu, Ze Ming; Qiao, Chang Sheng; Jia, Shi Ru

    2016-01-01

    The effects of a direct current (DC) electric field on the growth and metabolism of Gluconacetobacter xylinus were investigated in static culture. When a DC electric field at 10 mA was applied using platinum electrodes to the culture broth, bacterial cellulose (BC) production was promoted in 12 h but was inhibited in the last 12 h as compared to the control (without DC electric field). At the cathode, the presence of the hydrogen generated a strong reductive environment that is beneficial to cell growth. As compared to the control, the activities of glycolysis and tricarboxylic acid cycle, as well as BC productivity were observed to be slightly higher in the first 12 h. However, due to the absence of sufficient oxygen, lactic acid was accumulated from pyruvic acid at 18 h, which was not in favor of BC production. At the anode, DC inhibited cell growth in 6 h when compared to the control. The metabolic activity in G. xylinus was inhibited through the suppression of the tricarboxylic acid cycle and glycolysis. At 18-24 h, cell density was observed to decrease, which might be due to the electrolysis of water that significantly dropped the pH of cultural broth far beyond the optimal range. Meanwhile, metabolites for self-protection were accumulated, for instance proline, glutamic acid, gluconic acid, and fatty acids. Notably, the accumulation of gluconic acid and lactic acid made it a really tough acid stress to cells at the anode and finally led to depression of cell growth.

  12. Production of bacterial cellulose using different carbon sources and culture media.

    Science.gov (United States)

    Mohammadkazemi, Faranak; Azin, Mehrdad; Ashori, Alireza

    2015-03-01

    In this work, the effects of carbon sources and culture media on the production and structural properties of bacterial cellulose (BC) have been studied. BC nanofibers were synthesized using Gluconacetobacter xylinus strain PTCC 1734. Media used were Hestrin-Schramm (H), Yamanaka (Y), and Zhou (Z). Five different carbon sources, namely date syrup, glucose, mannitol, sucrose, and food-grade sucrose were used in these media. All the produced BC pellicles were characterized in terms of dry weight production, biomass yield, thermal stability, crystallinity and morphology by thermogravimetric analysis (TGA), x-ray diffraction (XRD), and field emission scanning electron microscopy (FE-SEM). The obtained results showed that mannitol lead to the highest yield, followed by sucrose. The highest production efficiency of mannitol might be due to the nitrogen source, which plays an important role. The maximum improvement on the thermal stability of the composites was achieved when mannitol was used in H medium. In addition, the crystallinity was higher in BC formed in H medium compared to other media. FE-SEM micrographs illustrated that the BC pellicles, synthesized in the culture media H and Z, were stable, unlike those in medium Y that were unstable. The micrographs of BC produced in media containing mannitol and sucrose provided evidence of the strong interfacial adhesion between the BC fibers without noticeable aggregates. PMID:25498666

  13. Production of nano bacterial cellulose from waste water of candied jujube-processing industry using Acetobacter xylinum.

    Science.gov (United States)

    Li, Zheng; Wang, Lifen; Hua, Jiachuan; Jia, Shiru; Zhang, Jianfei; Liu, Hao

    2015-04-20

    The work is aimed to investigate the suitability of waste water of candied jujube-processing industry for the production of bacterial cellulose (BC) by Gluconacetobacter xylinum CGMCC No.2955 and to study the structure properties of bacterial cellulose membranes. After acid pretreatment, the glucose of hydrolysate was higher than that of waste water of candied jujube. The volumetric yield of bacterial cellulose in hydrolysate was 2.25 g/L, which was 1.5-folds of that in waste water of candied jujube. The structures indicated that the fiber size distribution was 3-14 nm in those media with an average diameter being around 5.9 nm. The crystallinity index of BC from pretreatment medium was lower than that of without pretreatment medium and BCs from various media had similar chemical binding. Ammonium citrate was a key factor for improving production yield and the crystallinity index of BC.

  14. Production of nano bacterial cellulose from waste water of candied jujube-processing industry using Acetobacter xylinum.

    Science.gov (United States)

    Li, Zheng; Wang, Lifen; Hua, Jiachuan; Jia, Shiru; Zhang, Jianfei; Liu, Hao

    2015-04-20

    The work is aimed to investigate the suitability of waste water of candied jujube-processing industry for the production of bacterial cellulose (BC) by Gluconacetobacter xylinum CGMCC No.2955 and to study the structure properties of bacterial cellulose membranes. After acid pretreatment, the glucose of hydrolysate was higher than that of waste water of candied jujube. The volumetric yield of bacterial cellulose in hydrolysate was 2.25 g/L, which was 1.5-folds of that in waste water of candied jujube. The structures indicated that the fiber size distribution was 3-14 nm in those media with an average diameter being around 5.9 nm. The crystallinity index of BC from pretreatment medium was lower than that of without pretreatment medium and BCs from various media had similar chemical binding. Ammonium citrate was a key factor for improving production yield and the crystallinity index of BC. PMID:25662694

  15. Measurements of open charm production with LHCb

    Energy Technology Data Exchange (ETDEWEB)

    Britsch, Markward; Schmelling, Michael; Aquines, Osvaldo; Maciuc, Florin; Popov, Dmitry; Zavertyaev, Mikhail; Briggl, Konrad; Schichtel, Peter [MPIK, Heidelberg (Germany)

    2011-07-01

    The LHCb experiment covers a unique kinematic range at the LHC. With its excellent vertex resolution and particle identification it has very good capabilities for heavy quark production measurements. In this contribution we report on open charm production in inelastic pp collisions at a center-of-mass energy of 7 TeV. Cross-sections have been determined for D{sup 0}/D{sup 0}, D{sup *{+-}}, D{sup {+-}}, and D{sub s}{sup {+-}} in bins of transverse momentum and rapidity in the region 0

  16. Electroweak Physics (diboson production) measurements with ATLAS

    Science.gov (United States)

    Bachas, K.; Atlas Collaboration

    2016-07-01

    This paper is intended to give an overview of the ATLAS results on the production cross sections of gauge boson pairs using data from pp collisions at √{{s}} = 7 TeV for W γ, Z γ, W± W±, ZZ, W± Z and WV , where V = W± or Z decaying hadronically and √{{s}} = 8 TeV for ZZ, W± W±, W± Z and W± W± at the LHC at CERN. The cross sections are found to be in agreement with the expectations from the Standard Model within the estimated uncertainties. The production cross section measurements also allow for studies of anomalous triple and quartic gauge couplings for which 95% confidence limits are set.

  17. Fermentative hydrogen production from hydrolyzed cellulosic feedstock prepared with a thermophilic anaerobic bacterial isolate

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Yung Chung [Department of Chemical Engineering, National Cheng Kung University, No. 1 University Road, Tainan 701 (China); Huang, Chi-Yu.; Fu, Tzu-Ning [Department of Environmental Engineering and Science, Tunghai University, Taichung 407 (China); Chen, Chun-Yen; Chang, Jo-Shu [Department of Chemical Engineering, National Cheng Kung University, No. 1 University Road, Tainan 701 (China); Sustainable Environment Research Center, National Cheng Kung University, Tainan (China)

    2009-08-15

    Hydrogen gas was produced via dark fermentation from natural cellulosic materials and {alpha}-cellulose via a two-step process, in which the cellulosic substrates were first hydrolyzed by an isolated cellulolytic bacterium Clostridium strain TCW1, and the resulting hydrolysates were then used as substrate for fermentative H{sub 2} production. The TCW1 strain was able to hydrolyze all the cellulosic materials examined to produce reducing sugars (RS), attaining the best reducing sugar production yield of 0.65 g reducing sugar/g substrate from hydrolysis of {alpha}-cellulose. The hydrolysates of those cellulosic materials were successfully converted to H{sub 2} via dark fermentation using seven H{sub 2}-producing bacterial isolates. The bioH{sub 2} production performance was highly dependent on the type of cellulosic feedstock used, the initial reducing sugar concentration (C{sub RS,o}) (ranging from 0.7 to 4.5 mg/l), as well as the composition of sugar and soluble metabolites present in the cellulosic hydrolysates. It was found that Clostridium butyricum CGS5 displayed the highest H{sub 2}-producing efficiency with a cumulative H{sub 2} production of 270 ml/l from {alpha}-cellulose hydrolysate (C{sub RS,o} = 4.52 mg/l) and a H{sub 2} yield of 7.40 mmol/g RS (or 6.66 mmol/g substrate) from napier grass hydrolysate (C{sub RS,o} = 1.22 g/l). (author)

  18. Using wastewater after lipid fermentation as substrate for bacterial cellulose production by Gluconacetobacter xylinus.

    Science.gov (United States)

    Huang, Chao; Guo, Hai-Jun; Xiong, Lian; Wang, Bo; Shi, Si-Lan; Chen, Xue-Fang; Lin, Xiao-Qing; Wang, Can; Luo, Jun; Chen, Xin-De

    2016-01-20

    In this study, lipid fermentation wastewater (fermentation broth after separation with yeast biomass) with high Chemical Oxygen Demand (COD) value of 25,591 mg/L was used as substrate for bacterial cellulose (BC) production by Gluconacetobacter xylinus for the first time. After 5 days of fermentation, the highest BC yield (0.659 g/L) was obtained. Both monosaccharide and polysaccharides present in lipid fermentation wastewater could be utilized by G. xylinus simultaneously during fermentation. By this bioconversion, 30.0% of COD could be removed after 10 days of fermentation and the remaining wastewater could be used for further BC fermentation. The crystallinity of BC samples in lipid fermentation wastewater increased gradually during fermentation but overall the environment of lipid fermentation wastewater showed small influence on BC structure by comparison with that in traditional HS medium by using FE-SEM, FTIR, and XRD. By this work, the possibility of using lipid fermentation wastewater containing low value carbohydrate polymer (extracellular polysaccharides) for high value carbohydrate polymer (BC) production was proven.

  19. Biocontrol of Fusarium graminearum Growth and Deoxynivalenol Production in Wheat Kernels with Bacterial Antagonists

    Directory of Open Access Journals (Sweden)

    Cuijuan Shi

    2014-01-01

    Full Text Available Fusarium graminearum is the main causal pathogen affecting small-grain cereals, and it produces deoxynivalenol, a kind of mycotoxin, which displays a wide range of toxic effects in human and animals. Bacterial strains isolated from peanut shells were investigated for their activities against F. graminearum by dual-culture plate and tip-culture assays. Among them, twenty strains exhibited potent inhibition to the growth of F. graminearum, and the inhibition rates ranged from 41.41% to 54.55% in dual-culture plate assay and 92.70% to 100% in tip-culture assay. Furthermore, eighteen strains reduced the production of deoxynivalenol by 16.69% to 90.30% in the wheat kernels assay. Finally, the strains with the strongest inhibitory activity were identified by morphological, physiological, biochemical methods and also 16S rDNA and gyrA gene analysis as Bacillus amyloliquefaciens. The current study highlights the potential application of antagonistic microorganisms and their metabolites in the prevention of fungal growth and mycotoxin production in wheat kernels. As a biological strategy, it might avoid safety problems and nutrition loss which always caused by physical and chemical strategies.

  20. Using wastewater after lipid fermentation as substrate for bacterial cellulose production by Gluconacetobacter xylinus.

    Science.gov (United States)

    Huang, Chao; Guo, Hai-Jun; Xiong, Lian; Wang, Bo; Shi, Si-Lan; Chen, Xue-Fang; Lin, Xiao-Qing; Wang, Can; Luo, Jun; Chen, Xin-De

    2016-01-20

    In this study, lipid fermentation wastewater (fermentation broth after separation with yeast biomass) with high Chemical Oxygen Demand (COD) value of 25,591 mg/L was used as substrate for bacterial cellulose (BC) production by Gluconacetobacter xylinus for the first time. After 5 days of fermentation, the highest BC yield (0.659 g/L) was obtained. Both monosaccharide and polysaccharides present in lipid fermentation wastewater could be utilized by G. xylinus simultaneously during fermentation. By this bioconversion, 30.0% of COD could be removed after 10 days of fermentation and the remaining wastewater could be used for further BC fermentation. The crystallinity of BC samples in lipid fermentation wastewater increased gradually during fermentation but overall the environment of lipid fermentation wastewater showed small influence on BC structure by comparison with that in traditional HS medium by using FE-SEM, FTIR, and XRD. By this work, the possibility of using lipid fermentation wastewater containing low value carbohydrate polymer (extracellular polysaccharides) for high value carbohydrate polymer (BC) production was proven. PMID:26572346

  1. Hadron production measurement from NA61/SHINE

    CERN Document Server

    Korzenev, A

    2013-01-01

    New results of NA61/SHINE on determination of charged hadron yields in proton-carbon interactions are presented. They aim to improve predictions of the neutrino flux in the T2K experiment. The data were recorded using a secondary-proton beam of 31 GeV/$c$ momentum from CERN SPS which impinges on a graphite target. To determine the inclusive production cross section for charged pions, kaons and protons the thin ($0.04\\, \\lambda_I$) target was exploited. Results of this measurement are used in the T2K beam simulation program to reweight hadron yields in the interaction vertex. At the same time, NA61/SHINE results obtained with the T2K replica target ($1.9\\, \\lambda_I$) allow to constrain hadron yields at the surface of the target. It would correspond to the constraint up to 90% of the neutrino flux, thus reducing significantly a model dependence of the neutrino beam prediction. All measured spectra are compared to predictions of hadron production models. In addition a status of the analysis of data collected by...

  2. Hadron production measurement from NA61/SHINE

    CERN Document Server

    Korzenev, A

    2013-01-01

    New results from the NA61/SHINE experiment on the determination of charged hadron yields in proton-carbon interactions are presented. They aim to improve predictions of the neutrino flux in the T2K experiment. The analysis is based on the main dataset collected by NA61/SHINE in the year 2009. The data were recorded using a secondary-proton beam of 31 GeV/$c$ momentum from CERN SPS which impinges on a graphite target. To determine the inclusive production cross section for charged pions, kaons and protons a thin target was exploited. Results of this measurement are used in the T2K beam simulation program to reweight hadron yields at the interaction vertex. At the same time, NA61/SHINE results obtained with the T2K replica target allow to constrain hadron yields at the surface of the target. This allows to constrain up to 90% of the neutrino flux, thus reducing significantly the model dependence of the neutrino beam prediction. All measured spectra are compared to predictions of hadron production models.

  3. Measurements using three-dimensional product imaging

    Directory of Open Access Journals (Sweden)

    A. Sioma

    2010-07-01

    Full Text Available This article discusses a method of creating a three-dimensional cast model using vision systems and how that model can be used in thequality assessment process carried out directly on the assembly line. The technology of active vision, consisting in illumination of theobject with a laser beam, was used to create the model. Appropriate configuration of camera position geometry and laser light allows thecollection of height profiles and construction of a 3D model of the product on their basis. The article discusses problems connected with the resolution of the vision system, resolution of the laser beam analysis, and resolution connected with the application of the successive height profiles on sample cast planes. On the basis of the model, measurements allowing assessment of dimension parameters and surface defects of a given cast are presented. On the basis of tests and analyses of such a threedimensional cast model, a range of checks which are possible to conduct using 3D vision systems is indicated.Testing casts using that technology allows rapid assessment of selected parameters. Construction of the product’s model and dimensional assessment take a few seconds, which significantly reduces the duration of checks in the technological process. Depending on the product, a few checks may be carried out simultaneously on the product’s model.The possibility of controlling all outgoing products, and creating and modifying the product parameter control program, makes the solutionhighly flexible, which is confirmed by pilot industrial implementations. The technology will be developed in terms of detection andidentification of surface defects. It is important due to the possibility of using such information for the purposes of selecting technologicalprocess parameters and observing the effect of changes in selected parameters on the cast parameter controlled in a vision system.

  4. Production and partial purification of protease by selected bacterial strains using raw milk as substrate

    Directory of Open Access Journals (Sweden)

    Prakash, S.

    2011-01-01

    Full Text Available Aims: The present study was investigated to optimize and partially purify the proteases produced by the food borne bacterial strains.Methodology and Results: Four bacterial strains such as Bacillus cereus, Proteus vulgaris, P. mirabilis and Enterobacter aerogenes were isolated from food wastes. These strains were individually inoculated in to the formulated culture media supplied with three different concentrations (1:1 to 1:3 of raw milk as major substrate. Among the concentrations, 1:2 ratio of substrate supplied medium showed maximum (0.133 to 8.000 IU/mL protease production by all the tested organisms. After optimization, the organisms were tested for protease production at various pH (3 to 9, and temperature (30 to 80 °C. The result showed that all the organisms were capable of producing maximum protease at pH 6 (8.533 to 10.133 IU/mL and at 50 °C (8.666 to 10.666 IU/mL. The crude enzymes produced by the tested organisms were individually purified by two different methods viz sodium alginate and ammonium sulphate-butanol methods. The purity of the protease determined in these two methods was ranged between 3.24 to 5.44 I and 3.13 to 5.55 IU/mL respectively. The partially purified enzymes were further analysed through SDS-PAGE; accordingly the molecular weight of protein produced by the test organisms was determined in between 49.44 and 50.98 kDa.Conclusion, significance and impact of study: Among the tested strains P. vulgaris was identified as the major protease producer in optimized culture condition of 50o C and pH6. The molecular mass of the partially purified protease of P. vulgaris was 50.32 KDa. Further research on optimization of other fermentation parameters using statistical tools with P. vulgaris is needed to scale up the process.

  5. Metabolic investigation in Gluconacetobacter xylinus and its bacterial cellulose production under a direct current electric field

    Directory of Open Access Journals (Sweden)

    Miao eLiu

    2016-03-01

    Full Text Available The effects of a direct current (DC electric field on the growth and metabolism of Gluconacetobacter xylinus were investigated in static culture. When a DC electric field at 10 mA was applied using platinum electrodes to the culture broth, bacterial cellulose (BC production was promoted in 12 hours (h but was inhibited in the last 12 h as compared to the control (without DC electric field. At the cathode, the presence of the hydrogen generated a strong reductive environment that is beneficial to cell growth. As compared to the control, the activities of glycolysis and tricarboxylic acid cycle, as well as BC productivity were observed to be slightly higher in the first 12 h. However, due to the absence of sufficient oxygen, lactic acid was accumulated from pyruvic acid at 18 h, which was not in favor of BC production. At the anode, DC inhibited cell growth in 6 h when compared to the control. The metabolic activity in G. xylinus was inhibited through the suppression of the tricarboxylic acid cycle and glycolysis. At 18-24 h, cell density was observed to decrease, which might be due to the electrolysis of water that significantly dropped the pH of cultural broth far beyond the optimal range. Meanwhile, metabolites for self-protection were accumulated, for instance proline, glutamic acid, gluconic acid and fatty acids. Notably, the accumulation of gluconic acid and lactic acid made it a really tough acid stress to cells at the anode and finally led to depression of cell growth.

  6. Metabolic Investigation in Gluconacetobacter xylinus and Its Bacterial Cellulose Production under a Direct Current Electric Field.

    Science.gov (United States)

    Liu, Miao; Zhong, Cheng; Zhang, Yu Ming; Xu, Ze Ming; Qiao, Chang Sheng; Jia, Shi Ru

    2016-01-01

    The effects of a direct current (DC) electric field on the growth and metabolism of Gluconacetobacter xylinus were investigated in static culture. When a DC electric field at 10 mA was applied using platinum electrodes to the culture broth, bacterial cellulose (BC) production was promoted in 12 h but was inhibited in the last 12 h as compared to the control (without DC electric field). At the cathode, the presence of the hydrogen generated a strong reductive environment that is beneficial to cell growth. As compared to the control, the activities of glycolysis and tricarboxylic acid cycle, as well as BC productivity were observed to be slightly higher in the first 12 h. However, due to the absence of sufficient oxygen, lactic acid was accumulated from pyruvic acid at 18 h, which was not in favor of BC production. At the anode, DC inhibited cell growth in 6 h when compared to the control. The metabolic activity in G. xylinus was inhibited through the suppression of the tricarboxylic acid cycle and glycolysis. At 18-24 h, cell density was observed to decrease, which might be due to the electrolysis of water that significantly dropped the pH of cultural broth far beyond the optimal range. Meanwhile, metabolites for self-protection were accumulated, for instance proline, glutamic acid, gluconic acid, and fatty acids. Notably, the accumulation of gluconic acid and lactic acid made it a really tough acid stress to cells at the anode and finally led to depression of cell growth. PMID:27014248

  7. Bacterial wall products induce downregulation of vascular endothelial growth factor receptors on endothelial cells via a CD14-dependent mechanism: implications for surgical wound healing.

    LENUS (Irish Health Repository)

    Power, C

    2012-02-03

    INTRODUCTION: Vascular endothelial growth factor (VEGF) is a potent mitogenic cytokine which has been identified as the principal polypeptide growth factor influencing endothelial cell (EC) migration and proliferation. Ordered progression of these two processes is an absolute prerequisite for initiating and maintaining the proliferative phase of wound healing. The response of ECs to circulating VEGF is determined by, and directly proportional to, the functional expression of VEGF receptors (KDR\\/Flt-1) on the EC surface membrane. Systemic sepsis and wound contamination due to bacterial infection are associated with significant retardation of the proliferative phase of wound repair. The effects of the Gram-negative bacterial wall components lipopolysaccharide (LPS) and bacterial lipoprotein (BLP) on VEGF receptor function and expression are unknown and may represent an important biological mechanism predisposing to delayed wound healing in the presence of localized or systemic sepsis. MATERIALS AND METHODS: We designed a series of in vitro experiments investigating this phenomenon and its potential implications for infective wound repair. VEGF receptor density on ECs in the presence of LPS and BLP was assessed using flow cytometry. These parameters were assessed in hypoxic conditions as well as in normoxia. The contribution of CD14 was evaluated using recombinant human (rh) CD14. EC proliferation in response to VEGF was quantified in the presence and absence of LPS and BLP. RESULTS: Flow cytometric analysis revealed that LPS and BLP have profoundly repressive effects on VEGF receptor density in normoxic and, more pertinently, hypoxic conditions. The observed downregulation of constitutive and inducible VEGF receptor expression on ECs was not due to any directly cytotoxic effect of LPS and BLP on ECs, as measured by cell viability and apoptosis assays. We identified a pivotal role for soluble\\/serum CD14, a highly specific bacterial wall product receptor, in

  8. Pesticide Side Effects in an Agricultural Soil Ecosystem as Measured by amoA Expression Quantification and Bacterial Diversity Changes.

    Directory of Open Access Journals (Sweden)

    Louise Feld

    Full Text Available Assessing the effects of pesticide hazards on microbiological processes in the soil is currently based on analyses that provide limited insight into the ongoing processes. This study proposes a more comprehensive approach. The side effects of pesticides may appear as changes in the expression of specific microbial genes or as changes in diversity. To assess the impact of pesticides on gene expression, we focused on the amoA gene, which is involved in ammonia oxidation. We prepared soil microcosms and exposed them to dazomet, mancozeb or no pesticide. We hypothesized that the amount of amoA transcript decreases upon pesticide application, and to test this hypothesis, we used reverse-transcription qPCR. We also hypothesized that bacterial diversity is affected by pesticides. This hypothesis was investigated via 454 sequencing and diversity analysis of the 16S ribosomal RNA and RNA genes, representing the active and total soil bacterial communities, respectively.Treatment with dazomet reduced both the bacterial and archaeal amoA transcript numbers by more than two log units and produced long-term effects for more than 28 days. Mancozeb also inhibited the numbers of amoA transcripts, but only transiently. The bacterial and archaeal amoA transcripts were both sensitive bioindicators of pesticide side effects. Additionally, the numbers of bacterial amoA transcripts correlated with nitrate production in N-amended microcosms. Dazomet reduced the total bacterial numbers by one log unit, but the population size was restored after twelve days. The diversity of the active soil bacteria also seemed to be re-established after twelve days. However, the total bacterial diversity as reflected in the 16S ribosomal RNA gene sequences was largely dominated by Firmicutes and Proteobacteria at day twelve, likely reflecting a halt in the growth of early opportunists and the re-establishment of a more diverse population. We observed no effects of mancozeb on diversity.

  9. Effect of heavy metals and phenol on bacterial decolourisation and COD reduction of sucrose-aspartic acid Maillard product

    Institute of Scientific and Technical Information of China (English)

    Sangeeta Yadav; Ram Chandra

    2013-01-01

    Melanodins are amino-carbonyl complex,predominantly present in sugarcane molasses based distillery wastewater as major source of colourant.The microbial decolourisation of melanoidin is a challenge due to its binding property with other co-pollutants of distillery waste.Results revealed that the presence of Zn2+ (2.00-20.00 mg/L) in melanoidin solution (1200 mg/L) stimulated the bacterial growth and sucrose-aspartic acid Maillard product (SAA) decolourisation as compared to control,while Fe3+ and Mn2+ at the same concentration inhibited the process.However,the presence of phenol (100 mg/L) along with Zn2+,Fe3+ and Mn2+ suppressed the bacterial growth,SAA decolourisation and MnP activity.The shrinkage and reduced number of bacterial cell count at higher concentration of heavy metals in presence of phenol was also observed under scanning electron microscope.

  10. In situ synthesis of bacterial cellulose/polycaprolactone blends for hot pressing nanocomposite films production.

    Science.gov (United States)

    Figueiredo, Ana R P; Silvestre, Armando J D; Pascoal Neto, Carlos; Freire, Carmen S R

    2015-11-01

    A series of bacterial cellulose (BC)/polycaprolactone (PCL) nanocomposite films were successfully prepared by supplementation of the BC culture medium with variable amounts of PCL powder followed by hot-pressing of the BC/PCL mixtures obtained after incubation. PCL powder was fully incorporated into the BC network during its production and did not change the BC network morphology. The obtained films showed a homogenous distribution of PCL throughout the BC network, as well as good thermal stability (up to 200 °C) and improved mechanical properties, when compared to pristine PCL. In addition, the intrinsic biodegradability and biocompatibility of the nanocellulose fibers and PCL opens the possibility of using this novel nanocomposite in the biomedical field and food packaging. The BC biosynthetic approach combined with the hot-pressing proved successful for the sustainable development of nanocomposites combining hydrophobic thermoplastic matrices and hydrophilic nanocellulose fibers, without the use of harmful organic solvents commonly used to dissolve this type of polymeric matrices. PMID:26256364

  11. Production of fungal and bacterial growth modulating secondary metabolites is widespread among mycorrhiza-associated streptomycetes

    Directory of Open Access Journals (Sweden)

    Schrey Silvia D

    2012-08-01

    Full Text Available Abstract Background Studies on mycorrhiza associated bacteria suggest that bacterial-fungal interactions play important roles during mycorrhiza formation and affect plant health. We surveyed Streptomyces Actinobacteria, known as antibiotic producers and antagonists of fungi, from Norway spruce mycorrhizas with predominantly Piloderma species as the fungal partner. Results Fifteen Streptomyces isolates exhibited substantial variation in inhibition of tested mycorrhizal and plant pathogenic fungi (Amanita muscaria, Fusarium oxysporum, Hebeloma cylindrosporum, Heterobasidion abietinum, Heterobasidion annosum, Laccaria bicolor, Piloderma croceum. The growth of the mycorrhiza-forming fungus Laccaria bicolor was stimulated by some of the streptomycetes, and Piloderma croceum was only moderately affected. Bacteria responded to the streptomycetes differently than the fungi. For instance the strain Streptomyces sp. AcM11, which inhibited most tested fungi, was less inhibitory to bacteria than other tested streptomycetes. The determined patterns of Streptomyces-microbe interactions were associated with distinct patterns of secondary metabolite production. Notably, potentially novel metabolites were produced by strains that were less antagonistic to fungi. Most of the identified metabolites were antibiotics (e.g. cycloheximide, actiphenol and siderophores (e.g. ferulic acid, desferroxiamines. Plant disease resistance was activated by a single streptomycete strain only. Conclusions Mycorrhiza associated streptomycetes appear to have an important role in inhibiting the growth of fungi and bacteria. Additionally, our study indicates that the Streptomyces strains, which are not general antagonists of fungi, may produce still un-described metabolites.

  12. Production of fungal and bacterial growth modulating secondary metabolites is widespread among mycorrhiza-associated streptomycetes

    Science.gov (United States)

    2012-01-01

    Background Studies on mycorrhiza associated bacteria suggest that bacterial-fungal interactions play important roles during mycorrhiza formation and affect plant health. We surveyed Streptomyces Actinobacteria, known as antibiotic producers and antagonists of fungi, from Norway spruce mycorrhizas with predominantly Piloderma species as the fungal partner. Results Fifteen Streptomyces isolates exhibited substantial variation in inhibition of tested mycorrhizal and plant pathogenic fungi (Amanita muscaria, Fusarium oxysporum, Hebeloma cylindrosporum, Heterobasidion abietinum, Heterobasidion annosum, Laccaria bicolor, Piloderma croceum). The growth of the mycorrhiza-forming fungus Laccaria bicolor was stimulated by some of the streptomycetes, and Piloderma croceum was only moderately affected. Bacteria responded to the streptomycetes differently than the fungi. For instance the strain Streptomyces sp. AcM11, which inhibited most tested fungi, was less inhibitory to bacteria than other tested streptomycetes. The determined patterns of Streptomyces-microbe interactions were associated with distinct patterns of secondary metabolite production. Notably, potentially novel metabolites were produced by strains that were less antagonistic to fungi. Most of the identified metabolites were antibiotics (e.g. cycloheximide, actiphenol) and siderophores (e.g. ferulic acid, desferroxiamines). Plant disease resistance was activated by a single streptomycete strain only. Conclusions Mycorrhiza associated streptomycetes appear to have an important role in inhibiting the growth of fungi and bacteria. Additionally, our study indicates that the Streptomyces strains, which are not general antagonists of fungi, may produce still un-described metabolites. PMID:22852578

  13. Production and Characterization of a New Bacterial Cellulose/Poly(Vinyl Alcohol Nanocomposite

    Directory of Open Access Journals (Sweden)

    Miguel Gama

    2013-05-01

    Full Text Available Bacterial cellulose (BC is characterized for its high water holding capacity, high crystallinity, an ultrafine fiber network and high tensile strength. This work demonstrates the production of a new interpenetrated polymer network nanocomposite obtained through the incorporation of poly(vinyl alcohol (PVA on the BC matrix and evaluates the effect of oven drying on the morphological, mechanical and mass transfer properties of the composite membranes. Both the addition of PVA and oven drying induce the appearance of larger pores (circa 1–3 µm in average diameter in dried BC/PVA membranes. Both types of treatments also affect the permeability of the composite, as assessed by the diffusion coefficients of polyethylene glycol (PEG molecules (900, 8,000, 35,000 and 100,000 Da across the membranes. Finally, the Young’s modulus of dry pristine BC decreases following PVA incorporation, resulting in a change from 3.5 GPa to 1 GPa and a five-fold loss in tensile strength.

  14. N-acetyl-L-cysteine affects growth, extracellular polysaccharide production, and bacterial biofilm formation on solid surfaces.

    Science.gov (United States)

    Olofsson, Ann-Cathrin; Hermansson, Malte; Elwing, Hans

    2003-08-01

    N-Acetyl-L-cysteine (NAC) is used in medical treatment of patients with chronic bronchitis. The positive effects of NAC treatment have primarily been attributed to the mucus-dissolving properties of NAC, as well as its ability to decrease biofilm formation, which reduces bacterial infections. Our results suggest that NAC also may be an interesting candidate for use as an agent to reduce and prevent biofilm formation on stainless steel surfaces in environments typical of paper mill plants. Using 10 different bacterial strains isolated from a paper mill, we found that the mode of action of NAC is chemical, as well as biological, in the case of bacterial adhesion to stainless steel surfaces. The initial adhesion of bacteria is dependent on the wettability of the substratum. NAC was shown to bind to stainless steel, increasing the wettability of the surface. Moreover, NAC decreased bacterial adhesion and even detached bacteria that were adhering to stainless steel surfaces. Growth of various bacteria, as monocultures or in a multispecies community, was inhibited at different concentrations of NAC. We also found that there was no detectable degradation of extracellular polysaccharides (EPS) by NAC, indicating that NAC reduced the production of EPS, in most bacteria tested, even at concentrations at which growth was not affected. Altogether, the presence of NAC changes the texture of the biofilm formed and makes NAC an interesting candidate for use as a general inhibitor of formation of bacterial biofilms on stainless steel surfaces.

  15. N-acetyl-L-cysteine affects growth, extracellular polysaccharide production, and bacterial biofilm formation on solid surfaces.

    Science.gov (United States)

    Olofsson, Ann-Cathrin; Hermansson, Malte; Elwing, Hans

    2003-08-01

    N-Acetyl-L-cysteine (NAC) is used in medical treatment of patients with chronic bronchitis. The positive effects of NAC treatment have primarily been attributed to the mucus-dissolving properties of NAC, as well as its ability to decrease biofilm formation, which reduces bacterial infections. Our results suggest that NAC also may be an interesting candidate for use as an agent to reduce and prevent biofilm formation on stainless steel surfaces in environments typical of paper mill plants. Using 10 different bacterial strains isolated from a paper mill, we found that the mode of action of NAC is chemical, as well as biological, in the case of bacterial adhesion to stainless steel surfaces. The initial adhesion of bacteria is dependent on the wettability of the substratum. NAC was shown to bind to stainless steel, increasing the wettability of the surface. Moreover, NAC decreased bacterial adhesion and even detached bacteria that were adhering to stainless steel surfaces. Growth of various bacteria, as monocultures or in a multispecies community, was inhibited at different concentrations of NAC. We also found that there was no detectable degradation of extracellular polysaccharides (EPS) by NAC, indicating that NAC reduced the production of EPS, in most bacteria tested, even at concentrations at which growth was not affected. Altogether, the presence of NAC changes the texture of the biofilm formed and makes NAC an interesting candidate for use as a general inhibitor of formation of bacterial biofilms on stainless steel surfaces. PMID:12902275

  16. Atomic force microscopy measurements of bacterial adhesion and biofilm formation onto clay-sized particles

    Science.gov (United States)

    Huang, Qiaoyun; Wu, Huayong; Cai, Peng; Fein, Jeremy B.; Chen, Wenli

    2015-11-01

    Bacterial adhesion onto mineral surfaces and subsequent biofilm formation play key roles in aggregate stability, mineral weathering, and the fate of contaminants in soils. However, the mechanisms of bacteria-mineral interactions are not fully understood. Atomic force microscopy (AFM) was used to determine the adhesion forces between bacteria and goethite in water and to gain insight into the nanoscale surface morphology of the bacteria-mineral aggregates and biofilms formed on clay-sized minerals. This study yields direct evidence of a range of different association mechanisms between bacteria and minerals. All strains studied adhered predominantly to the edge surfaces of kaolinite rather than to the basal surfaces. Bacteria rarely formed aggregates with montmorillonite, but were more tightly adsorbed onto goethite surfaces. This study reports the first measured interaction force between bacteria and a clay surface, and the approach curves exhibited jump-in events with attractive forces of 97 ± 34 pN between E. coli and goethite. Bond strengthening between them occurred within 4 s to the maximum adhesion forces and energies of -3.0 ± 0.4 nN and -330 ± 43 aJ (10-18 J), respectively. Under the conditions studied, bacteria tended to form more extensive biofilms on minerals under low rather than high nutrient conditions.

  17. Atomic force microscopy measurements of bacterial adhesion and biofilm formation onto clay-sized particles.

    Science.gov (United States)

    Huang, Qiaoyun; Wu, Huayong; Cai, Peng; Fein, Jeremy B; Chen, Wenli

    2015-11-20

    Bacterial adhesion onto mineral surfaces and subsequent biofilm formation play key roles in aggregate stability, mineral weathering, and the fate of contaminants in soils. However, the mechanisms of bacteria-mineral interactions are not fully understood. Atomic force microscopy (AFM) was used to determine the adhesion forces between bacteria and goethite in water and to gain insight into the nanoscale surface morphology of the bacteria-mineral aggregates and biofilms formed on clay-sized minerals. This study yields direct evidence of a range of different association mechanisms between bacteria and minerals. All strains studied adhered predominantly to the edge surfaces of kaolinite rather than to the basal surfaces. Bacteria rarely formed aggregates with montmorillonite, but were more tightly adsorbed onto goethite surfaces. This study reports the first measured interaction force between bacteria and a clay surface, and the approach curves exhibited jump-in events with attractive forces of 97 ± 34 pN between E. coli and goethite. Bond strengthening between them occurred within 4 s to the maximum adhesion forces and energies of -3.0 ± 0.4 nN and -330 ± 43 aJ (10(-18) J), respectively. Under the conditions studied, bacteria tended to form more extensive biofilms on minerals under low rather than high nutrient conditions.

  18. Abundance and diversity of sedimentary bacterial communities in a coastal productive setting in the Western Irish Sea

    Science.gov (United States)

    O'Reilly, S. S.; Pentlavalli, P.; Flanagan, P. V.; Allen, C. C. R.; Monteys, X.; Szpak, M. T.; Murphy, B. T.; Jordan, S. F.; Kelleher, B. P.

    2016-02-01

    The bacterial community composition and biomass abundance from a depositional mud belt in the western Irish Sea and regional sands were investigated by phospholipid ester-linked fatty acid profiling, denaturing gradient gel electrophoresis and barcoded pyrosequencing of 16S rRNA genes. The study area varied by water depth (12-111 m), organic carbon content (0.09-1.57% TOC), grain size, hydrographic regime (well-mixed vs. stratified), and water column phytodetrital input (represented by algal polyunsaturated PLFA). The relative abundance of bacterial-derived PLFA (sum of methyl-branched, cyclopropyl and odd-carbon number PLFA) was positively correlated with fine-grained sediment, and was highest in the depositional mud belt. A strong association between bacterial biomass and eukaryote primary production was suggested based on observed positive correlations with total nitrogen and algal polyunsaturated fatty acids. In addition, 16S rRNA genes affiliated to the classes Clostridia and Flavobacteria represented a major proportion of total 16S rRNA gene sequences. This suggests that benthic bacterial communities are also important degraders of phytodetrital organic matter and closely coupled to water column productivity in the western Irish Sea.

  19. Effect of inoculum conditioning on hydrogen fermentation and pH effect on bacterial community relevant to hydrogen production.

    Science.gov (United States)

    Kawagoshi, Yasunori; Hino, Naoe; Fujimoto, Aya; Nakao, Masaharu; Fujita, Yukiko; Sugimura, Seiji; Furukawa, Kenji

    2005-11-01

    The effect of conditioning for a variety of inoculums on fermentative hydrogen production was investigated. In addition, the effects of pH condition on hydrogen fermentation and bacterial community were investigated. The effect of conditioning on hydrogen production was different depending on the inoculum types. An appreciable hydrogen production was shown with anaerobic digested sludge and lake sediment without conditioning, however, no hydrogen was produced when refuse compost and kiwi grove soil were used as inoculums without conditioning. The highest hydrogen production was obtained with heat-conditioned anaerobic digested sludge, almost the same production was also obtained with unconditioned digested sludge. The pH condition considerably affected hydrogen fermentation, hydrogen gas was efficiently produced with unconditioned anaerobic sludge when the pH was controlled at 6.0 throughout the culture period and not when only the initial pH was adjusted to 6.0 and 7.0. Hydrogen production decreased when the culture pH was only adjusted at the beginning of each batch in continuous batch culture, and additionally, bacterial community varied with the change in hydrogen production. It was suggested that Clostridium and Coprothermobacter species played important role in hydrogen fermentation, and Lactobacillus species had an adverse effect on hydrogen production.

  20. Product Stigmaticity: Understanding, Measuring and Managing Product-Related Stigma

    NARCIS (Netherlands)

    Vaes, K.

    2014-01-01

    Stigma-free Product Design. Many of the products intended to relieve us from discomforting or unsafe situations and many medical and assistive devices are experienced as unpleasant and uncomfortable. On top of their discomfort, product users may also experience social unease from the people around t

  1. The effects of indoor and outdoor dust exposure on the growth, sensitivity to oxidative-stress, and biofilm production of three opportunistic bacterial pathogens.

    Science.gov (United States)

    Suraju, Mohammed O; Lalinde-Barnes, Sloan; Sanamvenkata, Sachindra; Esmaeili, Mahsa; Shishodia, Shishir; Rosenzweig, Jason A

    2015-12-15

    Within the last decade, many studies have highlighted the radical changes in the components of indoor and outdoor dust. For example, agents like automobile emitted platinum group elements and different kinds of organic phthalates and esters have been reported to be accumulating in the biosphere. Humans consistently face dermal, respiratory, and dietary exposures to these particles while indoors and outdoors. In fact, dust particulate matter has been associated with close to 500,000 deaths per year in Europe and about 200,000 deaths per year in the United States. To date, there has been limited examination of the physiological impact of indoor and outdoor dust exposure on normal flora microbes. In this study, the effect of indoor- and outdoor-dust exposure on three opportunistic bacterial species (Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa) was assessed. Specifically, bacterial growth, oxidative stress resistance, and biofilm production were measured following indoor- and outdoor-dust exposures. Studies were conducted in nutritionally-rich and -poor environments typically encountered by bacteria. Surprisingly, indoor-dust (200μg/mL), enhanced the growth of all three bacterial species in nutrient-poor conditions, but slowed growth in nutrient-rich conditions. In nutrient-rich medium, 100μg/mL exposure of either indoor- or outdoor-dust resulted in significantly reduced oxidative stress resistance in E. coli. Most interestingly, dust (indoor and outdoor), either in nutrient-rich or -poor conditions, significantly increased biofilm production in all three bacterial species. These data suggest that indoor and outdoor dust, can modify opportunistic bacteria through altering growth, sensitivity to oxidative stress, and their virulence potential through enhanced biofilm formation.

  2. Effect of Cultivation Time and Medium Condition in Production of Bacterial Cellulose Nanofiber for Urease Immobilization

    OpenAIRE

    M. Pesaran; Gh. Amoabediny; F. Yazdian

    2015-01-01

    A new nanoporous biomatrix originated from bacterial resources has been chosen for urease immobilization. Urease has been immobilized on synthesized bacterial cellulose nanofiber since this enzyme has a key role in nitrogen metabolism. Gluconacetobacter xylinum ATCC 10245 has been cultivated for synthesis of a nanofiber with the diameter of 30–70 nm. Different cultivation processes in the aspect of time and cultivation medium conditions were chosen to study the performance of immobilized enzy...

  3. Optimization of Culture Parameters for Maximum Polyhydroxybutyrate Production by Selected Bacterial Strains Isolated from Rhizospheric Soils.

    Science.gov (United States)

    Lathwal, Priyanka; Nehra, Kiran; Singh, Manpreet; Jamdagni, Pragati; Rana, Jogender S

    2015-01-01

    The enormous applications of conventional non-biodegradable plastics have led towards their increased usage and accumulation in the environment. This has become one of the major causes of global environmental concern in the present century. Polyhydroxybutyrate (PHB), a biodegradable plastic is known to have properties similar to conventional plastics, thus exhibiting a potential for replacing conventional non-degradable plastics. In the present study, a total of 303 different bacterial isolates were obtained from soil samples collected from the rhizospheric area of three crops, viz., wheat, mustard and sugarcane. All the isolates were screened for PHB (Poly-3-hydroxy butyric acid) production using Sudan Black staining method, and 194 isolates were found to be PHB positive. Based upon the amount of PHB produced, the isolates were divided into three categories: high, medium and low producers. Representative isolates from each category were selected for biochemical characterization; and for optimization of various culture parameters (carbon source, nitrogen source, C/N ratio, different pH, temperature and incubation time periods) for maximizing PHB accumulation. The highest PHB yield was obtained when the culture medium was supplemented with glucose as the carbon source, ammonium sulphate at a concentration of 1.0 g/l as the nitrogen source, and by maintaining the C/N ratio of the medium as 20:1. The physical growth parameters which supported maximum PHB accumulation included a pH of 7.0, and an incubation temperature of 30 degrees C for a period of 48 h. A few isolates exhibited high PHB accumulation under optimized conditions, thus showing a potential for their industrial exploitation. PMID:26638531

  4. Developing new approaches to measuring NHS outputs and productivity

    OpenAIRE

    Mary OMahony; Philip Stevens; Lucy Stokes; Pete Loveridge

    2005-01-01

    In March 2004 the Department of Health commissioned a research team from the Centre for Health Economics at the University of York and the National Institute for Economic and Social Research to develop new approaches to measuring NHS outputs and productivity. The research objectives were development of: 1)A comprehensive measure of NHS outputs and productivity. 2) Methods to facilitate regular in-year analysis of NHS productivity. 3) Output measures capable of measuring efficiency and product...

  5. Toxicity of fungicides to natural bacterial communities in wetland water and sediment measured using leucine incorporation and potential denitrification.

    Science.gov (United States)

    Milenkovski, Susann; Bååth, Erland; Lindgren, Per-Eric; Berglund, Olof

    2010-02-01

    We assessed potential toxicity of fungicides to natural bacterial communities from a constructed wetland, located in southern Sweden, and compared the sensitivity of two endpoints indicating bacterial activity, leucine incorporation, and potential denitrification, in detecting toxicity. The effects of eight fungicides (benomyl, carbendazim, carboxin, captan, cycloheximide, fenpropimorph, propiconazole, and thiram), two bactericides (bronopol and chlortetracycline) as controls, and one reference compound (3,5-dichlorophenol), were tested in a water-sediment microcosm set-up. Leucine incorporation was measured in both the water and sediment column, while potential denitrification was measured for the entire microcosm. The bactericides and the reference compound gave sigmoid concentration-response curves for both endpoints in all but one case. The fungicides thiram, captan, and benomyl, and to a lesser extent fenpropimorph and propiconazole had quantifiable toxic effects on leucine incorporation, with EC(50) values ranging from 3 to 70 mg l(-1), while carbendazim, carboxin, and cycloheximide had little effect at the investigated concentrations. Only thiram and captan inhibited potential denitrification; the other fungicides showed no quantifiable effect. A greater toxic effect on leucine incorporation was recorded for bacterial communities associated with the water column, compared to the sediment column, for all tested compounds. Leucine incorporation was the more sensitive method for toxicity assessment of bacterial communities, and also allowed for a rapid and simple way of comparing exposure in the sediment and water column, making it an attractive standard method for community based toxicological assays in aquatic environments.

  6. Productivity measurement in hospital libraries: a case report.

    OpenAIRE

    Phillips, S A

    1990-01-01

    This paper examines the concept of productivity measurement and its application in a hospital library. Component steps in development of a typical productivity measurement system are described, including a process for calculation of quantitative workload standards. Problems and potential benefits of participating in productivity measurement programs are discussed, and managerial strategies suggested.

  7. Single-taxon field measurements of bacterial gene regulation controlling DMSP fate.

    Science.gov (United States)

    Varaljay, Vanessa A; Robidart, Julie; Preston, Christina M; Gifford, Scott M; Durham, Bryndan P; Burns, Andrew S; Ryan, John P; Marin, Roman; Kiene, Ronald P; Zehr, Jonathan P; Scholin, Christopher A; Moran, Mary Ann

    2015-07-01

    The 'bacterial switch' is a proposed regulatory point in the global sulfur cycle that routes dimethylsulfoniopropionate (DMSP) to two fundamentally different fates in seawater through genes encoding either the cleavage or demethylation pathway, and affects the flux of volatile sulfur from ocean surface waters to the atmosphere. Yet which ecological or physiological factors might control the bacterial switch remains a topic of considerable debate. Here we report the first field observations of dynamic changes in expression of DMSP pathway genes by a single marine bacterial species in its natural environment. Detection of taxon-specific gene expression in Roseobacter species HTCC2255 during a month-long deployment of an autonomous ocean sensor in Monterey Bay, CA captured in situ regulation of the first gene in each DMSP pathway (dddP and dmdA) that corresponded with shifts in the taxonomy of the phytoplankton community. Expression of the demethylation pathway was relatively greater during a high-DMSP-producing dinoflagellate bloom, and expression of the cleavage pathway was greater in the presence of a mixed diatom and dinoflagellate community [corrected].These field data fit the prevailing hypothesis for bacterial DMSP gene regulation based on bacterial sulfur demand, but also suggest a modification involving oxidative stress response, evidenced as upregulation of catalase via katG, when DMSP is demethylated. PMID:25700338

  8. Inadequate clearance of translocated bacterial products in HIV-infected humanized mice.

    Directory of Open Access Journals (Sweden)

    Ursula Hofer

    2010-04-01

    Full Text Available Bacterial translocation from the gut and subsequent immune activation are hallmarks of HIV infection and are thought to determine disease progression. Intestinal barrier integrity is impaired early in acute retroviral infection, but levels of plasma lipopolysaccharide (LPS, a marker of bacterial translocation, increase only later. We examined humanized mice infected with HIV to determine if disruption of the intestinal barrier alone is responsible for elevated levels of LPS and if bacterial translocation increases immune activation. Treating uninfected mice with dextran sodium sulfate (DSS induced bacterial translocation, but did not result in elevated plasma LPS levels. DSS-induced translocation provoked LPS elevation only when phagocytic cells were depleted with clodronate liposomes (clodrolip. Macrophages of DSS-treated, HIV-negative mice phagocytosed more LPS ex vivo than those of control mice. In HIV-infected mice, however, LPS phagocytosis was insufficient to clear the translocated LPS. These conditions allowed higher levels of plasma LPS and CD8+ cell activation, which were associated with lower CD4+/CD8+ cell ratios and higher viral loads. LPS levels reflect both intestinal barrier and LPS clearance. Macrophages are essential in controlling systemic bacterial translocation, and this function might be hindered in chronic HIV infection.

  9. 77 FR 18916 - Production Measurement Documents Incorporated by Reference

    Science.gov (United States)

    2012-03-29

    ... with up-to-date standards for measuring oil and gas production volumes. This rule will result in more accurate and efficient measurement of oil and gas production. DATES: Effective Date: This final rule... measurement standards to provide industry with up-to-date guidance for measurement technology....

  10. Size of bacterial ice-nucleation sites measured in situ by radiation inactivation analysis

    OpenAIRE

    Govindarajan, Arepura G.; Lindow, Steven E.

    1988-01-01

    Four bacterial species are known to catalyze ice formation at temperatures just below 0°C. To better understand the relationship between the molecular structure of bacterial ice-nucleation site(s) and the quantitative and qualitative features of the ice-nucleation-active phenotype, we determined by γ-radiation analysis the in situ size of ice-nucleation sites in strains of Pseudomonas syringae and Erwinia herbicola and in Escherichia coli HB101 carrying the plasmid pICE1.1 (containing a 4-kil...

  11. Controls on bacterial and archaeal community structure and greenhouse gas production in natural, mined, and restored Canadian peatlands

    Directory of Open Access Journals (Sweden)

    Nathan eBasiliko

    2013-07-01

    Full Text Available Northern peatlands are important global C reservoirs, largely because of their slow rates of microbial C mineralization. Particularly in sites that are heavily influenced by anthropogenic disturbances, there is scant information about microbial ecology and whether or not microbial community structure influences greenhouse gas production. This work characterized communities of bacteria and archaea using terminal restriction fragment length polymorphism and sequence analysis of 16S rRNA and functional genes across eight natural, mined, or restored peatlands in two locations in eastern Canada. Correlations were explored among chemical properties of peat, bacterial and archaeal community structure, and carbon dioxide and methane production rates under oxic and anoxic conditions. Bacteria and archaea similar to those found in other peat soil environments were detected. In contrast to other reports, methanogen diversity was low in our study, with only 2 groups of known or suspected methanogens. Although mining and restoration affected substrate availability and microbial activity, these land-uses did not consistently affect bacterial or archaeal community composition. In fact, larger differences were observed between the two locations and between oxic and anoxic peat samples than between mined and restored sites, with anoxic samples characterized by less detectable bacterial diversity and stronger dominance by members of the phylum Acidobacteria. There were also no apparent strong linkages between prokaryote community structure and methane or carbon dioxide production, suggesting that different organisms exhibit functional redundancy and/or that the same taxa function at very different rates when exposed to different peat substrates. In contrast to other earlier work focusing on fungal communities across similar mined and restored peatlands, bacterial and archaeal communities appeared to be more resistant or resilient to peat substrate changes brought

  12. 75 FR 72761 - Production Measurement Documents Incorporated by Reference

    Science.gov (United States)

    2010-11-26

    ... compliance with this standard, may have a higher uncertainty than liquid measurement based on the... Measurement Documents Incorporated by Reference AGENCY: Bureau of Ocean Energy Management, Regulation and... new production measurement industry standards into the regulations governing oil, gas, and...

  13. Examining Academic and Administrative Productivity Measures.

    Science.gov (United States)

    Middaugh, Michael F.; Hollowell, David E.

    1992-01-01

    The "academic ratchet and administrative lattice" framework for examining costs and productivity in college administration is applied to the University of Delaware. The productivity of academic units is analyzed quantitatively and issues in overstaffing and overbudgeting of administrative units are discussed. Faculty staffing trends from 1984-85…

  14. Measured moisture properties for alternative insulation products

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan De Place; Hansen, Kurt Kielsgaard; Padfield, Tim

    1999-01-01

    During the past few years there has been a growing interest in using alternative insulation products in buildings. Among these products are the organic materials cellulose fibre, flax and sheep's wool as well as the inorganic perlite. The organic materials are regarded with some suspicion, because...

  15. Measuring Productivity Growth in the Bahraini Agriculture and Fisheries Sector

    OpenAIRE

    Shebeb, Bassim

    2006-01-01

    The main objective of this study is to measure and analyze one of the major components of economic performance, multifactor productivity (MFP) growth rate adjusted for economies of scale, and to measure and analyze the growth rate of partial (input-specific) productivity in the Bahraini Agriculture and Fisheries Sector (primary sector) over the time period 1980-2002. A dual cost measure of multifactor productivity growth was developed to obtain a highly interpretable measure of economic perfo...

  16. Product mixes as objects of choice in nonparametric efficiency measurement

    OpenAIRE

    Laurens Cherchye; Tom Vanpuyenbroeck

    1999-01-01

    Non-radial measures of technical efficiency essentially differ from their radial counterparts in that the product mix of the efficient reference is allowed to be different from the product mix of the evaluated observation. Whereas existing non-radial measures are still based on the product mix of the evaluated, i.e. possibly inefficient observation, we change the perspective and propose a measure based on the mix properties of the efficient reference. The resulting `inverse' measure can be co...

  17. Establishment of rumen-mimic bacterial consortia: A functional union for bio-hydrogen production from cellulosic bioresource

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jui-Jen [Genomics Research Center, Academia Sinica, Nankang, Taipei 115 (China); Lin, Jia-Jen; Ho, Cheng-Yu.; Chin, Wei-Chih; Huang, Chieh-Chen [Department of Life Sciences, National Chung Hsing University,Taichung (China)

    2010-12-15

    The study aimed to establish stable rumen-mimic bacterial consortia as a functional union for simultaneous saccharification and fermentation from cellulosic bioresource. The consortia was constructed by repeated-batch culture with ruminal microflora and napiergrass at 38 C. The major bacterial composition of batch culture was monitored by 16S rRNA gene-targeted denaturing gradient gel electrophoresis (DGGE). The result showed that a stable consortia constituted by ruminal microflora was formed, and the consortia includes bacterial strains such as Clostridium xylanolyticum, Clostridium papyrosolvens, Clostridium beijerinckii, Ruminococcus sp., Ethanoligenens harbinense, and Desulfovibrio desulfuricans. The Clostridium genus was showed as the dominant population in the system and contributed to the biohydrogen production. During each eight days incubation period, the functional consortia could degrade an average of 27% hemicellulose and 2% cellulose from napiergrass biomass. While the increasing of the reducing sugars and their converting to biohydrogen gas productivity were also observed. The time course profile for cellulytic enzymes showed that the hydrolysis of complex lignocellulosic material may occur through the ordered actions of xylenase and cellulase activities. (author)

  18. Measuring the CCN and IN ability of bacterial isolates: implications for the southeastern United States and Puerto Rico

    Science.gov (United States)

    Purdue, S.; Waters, S.; Konstantinidis, K.; Nenes, A.; DeLeon-Rodriguez, N.

    2015-12-01

    Ice nucleation is an important process in the climate system as it influences global precipitation processes, and can affect the vertical distribution of clouds with effects that both cool and warm the atmosphere. Of the pathways to ice nucleation, immersion mode, which occurs when ice nuclei (IN) particles are surrounded by an aqueous phase that subsequently freezes, dominates primary ice production in mixed-phase clouds. A simple but effective method to study immersion freezing is to utilize a droplet freezing assay (DFA) that consists of an aluminum plate, precisely cooled by a continuous flow of an ethylene glycol-water mixture. Using such a system we study the immersion IN characteristics of bacterial isolates (for temperatures ranging from -15oC to 0oC) isolated from rainwater and air collected in Atlanta, GA and Puerto Rico, over storms throughout the year. Despite their relatively large size and the presence of hydrophilic groups on the outer membranes of many bacteria, it is unclear if bacteria possess an inherent ability to nucleate an aqueous phase (a requirement for immersion freezing) for the wide range of supersaturations found in clouds. For this, we measure the cloud condensation nucleation (CCN) activity of each isolate (over the 0.05% to 0.6% supersaturation range) using a Continuous Flow Streamwise Thermal Gradient CCN Counter. Initial results have shown certain isolates to be very efficient CCN, allowing them to form droplets even for the very low supersaturations found in radiation fogs. In combination, these experiments provide insight into the potential dual-ability of some bacteria, isolated from the southeastern United States and Puerto Rico, to act as both efficient CCN and IN.

  19. Engineering control of bacterial cellulose production using a genetic toolkit and a new cellulose-producing strain.

    Science.gov (United States)

    Florea, Michael; Hagemann, Henrik; Santosa, Gabriella; Abbott, James; Micklem, Chris N; Spencer-Milnes, Xenia; de Arroyo Garcia, Laura; Paschou, Despoina; Lazenbatt, Christopher; Kong, Deze; Chughtai, Haroon; Jensen, Kirsten; Freemont, Paul S; Kitney, Richard; Reeve, Benjamin; Ellis, Tom

    2016-06-14

    Bacterial cellulose is a strong and ultrapure form of cellulose produced naturally by several species of the Acetobacteraceae Its high strength, purity, and biocompatibility make it of great interest to materials science; however, precise control of its biosynthesis has remained a challenge for biotechnology. Here we isolate a strain of Komagataeibacter rhaeticus (K. rhaeticus iGEM) that can produce cellulose at high yields, grow in low-nitrogen conditions, and is highly resistant to toxic chemicals. We achieved external control over its bacterial cellulose production through development of a modular genetic toolkit that enables rational reprogramming of the cell. To further its use as an organism for biotechnology, we sequenced its genome and demonstrate genetic circuits that enable functionalization and patterning of heterologous gene expression within the cellulose matrix. This work lays the foundations for using genetic engineering to produce cellulose-based materials, with numerous applications in basic science, materials engineering, and biotechnology.

  20. An overview of food safety and bacterial foodborne zoonoses in food production animals in the Caribbean region.

    Science.gov (United States)

    Guerra, Maria Manuela Mendes; de Almeida, Andre M; Willingham, Arve Lee

    2016-08-01

    Foodborne diseases (FBDs) in the Caribbean have a high economic burden. Public health and tourism concerns rise along with the increasing number of cases and outbreaks registered over the last 20 years. Salmonella spp., Shigella spp., and Campylobacter spp. are the main bacteria associated with these incidents. In spite of undertaking limited surveillance on FBD in the region, records related to bacterial foodborne zoonoses in food-producing animals and their associated epidemiologic significance are poorly documented, giving rise to concerns about the importance of the livestock, food animal product sectors, and consumption patterns. In this review, we report the available published literature over the last 20 years on selected bacterial foodborne zoonoses in the Caribbean region and also address other food safety-related aspects (e.g., FBD food attribution, importance, surveillance), mainly aiming at recognizing data gaps and identifying possible research approaches in the animal health sector. PMID:27215411

  1. Engineering control of bacterial cellulose production using a genetic toolkit and a new cellulose-producing strain

    Science.gov (United States)

    Florea, Michael; Hagemann, Henrik; Santosa, Gabriella; Micklem, Chris N.; Spencer-Milnes, Xenia; de Arroyo Garcia, Laura; Paschou, Despoina; Lazenbatt, Christopher; Kong, Deze; Chughtai, Haroon; Jensen, Kirsten; Freemont, Paul S.; Kitney, Richard; Reeve, Benjamin; Ellis, Tom

    2016-01-01

    Bacterial cellulose is a strong and ultrapure form of cellulose produced naturally by several species of the Acetobacteraceae. Its high strength, purity, and biocompatibility make it of great interest to materials science; however, precise control of its biosynthesis has remained a challenge for biotechnology. Here we isolate a strain of Komagataeibacter rhaeticus (K. rhaeticus iGEM) that can produce cellulose at high yields, grow in low-nitrogen conditions, and is highly resistant to toxic chemicals. We achieved external control over its bacterial cellulose production through development of a modular genetic toolkit that enables rational reprogramming of the cell. To further its use as an organism for biotechnology, we sequenced its genome and demonstrate genetic circuits that enable functionalization and patterning of heterologous gene expression within the cellulose matrix. This work lays the foundations for using genetic engineering to produce cellulose-based materials, with numerous applications in basic science, materials engineering, and biotechnology. PMID:27247386

  2. Engineering control of bacterial cellulose production using a genetic toolkit and a new cellulose-producing strain.

    Science.gov (United States)

    Florea, Michael; Hagemann, Henrik; Santosa, Gabriella; Abbott, James; Micklem, Chris N; Spencer-Milnes, Xenia; de Arroyo Garcia, Laura; Paschou, Despoina; Lazenbatt, Christopher; Kong, Deze; Chughtai, Haroon; Jensen, Kirsten; Freemont, Paul S; Kitney, Richard; Reeve, Benjamin; Ellis, Tom

    2016-06-14

    Bacterial cellulose is a strong and ultrapure form of cellulose produced naturally by several species of the Acetobacteraceae Its high strength, purity, and biocompatibility make it of great interest to materials science; however, precise control of its biosynthesis has remained a challenge for biotechnology. Here we isolate a strain of Komagataeibacter rhaeticus (K. rhaeticus iGEM) that can produce cellulose at high yields, grow in low-nitrogen conditions, and is highly resistant to toxic chemicals. We achieved external control over its bacterial cellulose production through development of a modular genetic toolkit that enables rational reprogramming of the cell. To further its use as an organism for biotechnology, we sequenced its genome and demonstrate genetic circuits that enable functionalization and patterning of heterologous gene expression within the cellulose matrix. This work lays the foundations for using genetic engineering to produce cellulose-based materials, with numerous applications in basic science, materials engineering, and biotechnology. PMID:27247386

  3. Bacterial Production of Poly(3-hydroxybutyrate): An Undergraduate Student Laboratory Experiment

    Science.gov (United States)

    Burns, Kristi L.; Oldham, Charlie D.; May, Sheldon W.

    2009-01-01

    As part of a multidisciplinary course that is cross-listed between five departments, we developed an undergraduate student laboratory experiment for culturing, isolating, and purifying the biopolymer, poly(3-hydroxybutyrate), PHB. This biopolyester accumulates in the cytoplasm of bacterial cells under specific growth conditions, and it has…

  4. Measurement of Inclusive $B \\to\\ psi$ Production

    CERN Document Server

    Anderson, S; Kubota, Y; Lee, S J; Li, S Z; Poling, R A; Smith, A; Stepaniak, C J; Urheim, J; Metreveli, Z V; Seth, K K; Tomaradze, A G; Zweber, P; Ahmed, S; Alam, M S; Jian, L; Saleem, M; Wappler, F; Eckhart, E; Gan, K K; Gwon, C; Hart, T; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pedlar, T K; Thayer, J B; Von Törne, E; Wilksen, T; Zoeller, M M; Muramatsu, H; Richichi, S J; Severini, H; Skubic, P L; Dytman, S A; Müller, J A; Nam, S; Savinov, V; Chen, S; Hinson, J W; Lee, J; Miller, D H; Pavlunin, V; Shibata, E I; Shipsey, I P J; Cronin-Hennessy, D; Lyon, A L; Park, C S; Park, W; Thorndike, E H; Coan, T E; Gao, Y S; Liu, F; Maravin, Y; Narsky, I; Stroynowski, R; Artuso, M; Boulahouache, C; Bukin, K; Dambasuren, E; Khroustalev, K; Moneti, G C; Mountain, R; Nandakumar, R; Skwarnicki, T; Stone, S; Wang, J C; Mahmood, A H; Csorna, S E; Danko, I; Xu, Z; Bonvicini, G; Cinabro, D; Dubrovin, M; McGee, S; Bornheim, A; Lipeles, E; Pappas, S P; Shapiro, A; Sun, W M; Weinstein, A J; Masek, G; Paar, H P; Mahapatra, R; Nelson, H N; Briere, R A; Chen, G P; Ferguson, T; Tatishvili, G T; Vogel, H; Adam, N E; Alexander, J P; Berkelman, K; Blanc, F; Boisvert, V; Cassel, David G; Drell, P S; Duboscq, J E; Ecklund, K M; Ehrlich, R; Gibbons, L; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Magerkurth, A; Mahlke-Krüger, H; Meyer, T O; Mistry, N B; Nordberg, E; Patterson, J R; Peterson, D; Pivarski, J; Riley, D; Sadoff, A J; Schwarthoff, H; Shepherd, M R; Thayer, J G; Urner, D; Valant-Spaight, B L; Viehhauser, G; Warburton, A; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Potlia, V; Stöck, H; Yelton, J; Brandenburg, G; Ershov, A; Kim, D Y J; Wilson, R; Benslama, K; Eisenstein, B I; Ernst, J; Gollin, G D; Hans, R M; Karliner, I; Lowrey, N; Marsh, M A; Plager, C; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Ammar, R; Besson, D; Zhao, X

    2002-01-01

    Using the combined CLEO II and CLEO II.V data sets of 9.1 fb^{-1} at the Upsilon(4S), we measure properties of Psi mesons produced directly from decays of the B meson, where ``B'' denotes an admixture of B+, B- B0, and B0bar, and ``Psi'' denotes either J/Psi or Psi(2S). We report first measurements of Psi polarization in B -> Psi(direct) X: alpha(J/Psi) = -0.30 {+0.07 -0.06 stat} {+-0.04 syst} and alpha(Psi(2S)) = -0.45 {+0.22 -0.19 stat} {+-0.04 syst}. We also report improved measurements of the momentum distributions of Psi produced directly from B decays, correcting for measurement smearing. Finally, we report measurements of the inclusive branching fraction for B -> Psi X and B -> Chi_c1 X.

  5. Issues in Measurement and International Comparison of Productivity - An Overview

    NARCIS (Netherlands)

    Van Ark, Bart

    1996-01-01

    This paper reviews recent development in theory and measurement of productivity performance in an international comparative perspective. It emphasises the need for a better link between the theory and practice of measurement, in particular concerning measurement of productivity levels. The paper dea

  6. Measuring mine soil productivity for forests

    International Nuclear Information System (INIS)

    The Surface Mining Control and Reclamation Act (SMCRA) of 1977 requires that mine operators reclaim mined land to achieve crop productivity levels equal to or greater than premined conditions. The standard for evaluating reforestation success is based solely on tree-seedling survival; however, survival is an estimator of stand density and not an indication of site productivity. The purpose of this study was to develop a model for estimating mine soil productivity based on the capability of growing merchantable timber. Seventy-eight fixed-area plots in Virginia and West Virginia were selected to evaluate the effects of mine soil/site properties on tree growth. These plots ranged from 0.02 to 0.04 ha and consisted of 5- to 9-year-old eastern white pine (Pinus strobus). A 1-m deep pit was dug at the base of one representative tree on each plot to determine rooting depth and physical and chemical properties of the subsurface horizons. The properties most correlated with tree growth were rooting volume, defined as the depth to a restrictive layer, slope percent, soil extractable phosphorus and manganese content, and electrical conductivity. A productivity model was developed based on the premise that limiting soil and site characteristics affect a species' optimum root distribution and thus its aboveground productivity. The developed model was verified using a white pine data set ranging in age from 11 to 15 years that was obtained from 14 reclaimed mines in Virginia. The model was significantly correlated with aboveground biomass and site index. Similar results were observed when predicted productivity estimates and site index values were added separately into established biomass equations

  7. Bacterial carbonatogenesis

    International Nuclear Information System (INIS)

    Several series of experiments in the laboratory as well as in natural conditions teach that the production of carbonate particles by heterotrophic bacteria follows different ways. The 'passive' carbonatogenesis is generated by modifications of the medium that lead to the accumulation of carbonate and bicarbonate ions and to the precipitation of solid particles. The 'active' carbonatogenesis is independent of the metabolic pathways. The carbonate particles are produced by ionic exchanges through the cell membrane following still poorly known mechanisms. Carbonatogenesis appears to be the response of heterotrophic bacterial communities to an enrichment of the milieu in organic matter. The active carbonatogenesis seems to start first. It is followed by the passive one which induces the growth of initially produced particles. The yield of heterotrophic bacterial carbonatogenesis and the amounts of solid carbonates production by bacteria are potentially very high as compared to autotrophic or chemical sedimentation from marine, paralic or continental waters. Furthermore, the bacterial processes are environmentally very ubiquitous; they just require organic matter enrichment. Thus, apart from purely evaporite and autotrophic ones, all Ca and/or Mg carbonates must be considered as from heterotrophic bacterial origin. By the way, the carbon of carbonates comes from primary organic matter. Such considerations ask questions about some interpretations from isotopic data on carbonates. Finally, bacterial heterotrophic carbonatogenesis appears as a fundamental phase in the relationships between atmosphere and lithosphere and in the geo-biological evolution of Earth. (author)

  8. Development of the Measurement of Product

    OpenAIRE

    Jaroslav Sixta

    2014-01-01

    The measurement of economy is a very long issue closely connected with the development of economic theories and the level of knowledge. Origin of modern measurement can be found in 17th century when Francois Quesnay compiled his Economic Table. Lots of successors developed economic concepts that are currently represented by the system of national accounting. Although national accounting has not a long history since it was established in 1950s, it has become known as a general tool for the des...

  9. Measurement of Charmonium Production Cross Section at LHCb

    CERN Multimedia

    Frosini, M

    2010-01-01

    The great abundance of charmonium states, collected from the start up of LHC, allows to study its production mechanism. In particular the total and differential $J/\\psi$ production cross section are measured in the transverse momentum range [0;10] GeV/$c$ and in the pseudorapidity range $y \\in$ [2.5;4]. The measurements are performed disentagling the prompt (direct production in $pp$ collisions and feed down from excited charmonium states) and delayed ($b$-hadron decays products) component.

  10. Culture-independent bacterial community analysis of the salty-fermented fish paste products of Thailand and Laos.

    Science.gov (United States)

    Marui, Junichiro; Boulom, Sayvisene; Panthavee, Wanchai; Momma, Mari; Kusumoto, Ken-Ichi; Nakahara, Kazuhiko; Saito, Masayoshi

    2015-01-01

    A bacterial community analysis, using a culture-independent method (polymerase chain reaction-denaturing gradient gel electrophoresis), detected 17 species of bacteria including species of the genera Tetragenococcus, Lactobacillus, Pediococcus, Weissella Halanaerobium, Clostridium, and Sphingomonas in a traditional salty-fermented fish paste known as pla-ra or pa-daek in Thailand and Laos, which is used as a storage-stable multi-purpose seasoning. The representative genus of lactic acid bacteria seemed to vary in the 10 products collected from Thailand and Laos. Tetragenococci were common in products from central Thailand and Vientiane in Laos which had salinities of not less than 11% and pH values ranging from 5.6 to 6.1. However, lactobacilli were common in products from northern Thailand which had the lowest salinities (8.3-8.6%) and pH values (4.5-4.8) of all the samples examined. Two Lactobacillus and one Tetragenococcus species were detected in one product from northeastern Thailand containing 10% salt. These results suggest that salinity in pla-ra/pa-daek is an important determinant of the representative genus of lactic acid bacteria such as, Tetragenococcus or Lactobacillus. Additionally, differences in the acidity between these two groups seemed to be related to the production of d-/l-lactic acid in the lactic acid bacteria in each product. This is the first study to report a correlation between bacterial community structure and taste components in pla-ra/pa-daek products from various regions. This scientific work on a traditional fermented food will be useful in helping local producers meet differing consumer preferences in various regions. PMID:25918672

  11. ATLAS measurements of soft particle production and diffraction

    CERN Document Server

    Todorova, S; The ATLAS collaboration

    2012-01-01

    The ATLAS Collaboration has measured a wide range of properties of soft particle production. These include forward-backward and azimuthal correlations, azimuthal ordering of hadron production, underlying event properties and their dependence on aspects of the hard scattering process. The inelastic and diffractive cross sections have also been measured, using particle tags and rapidity gaps. Many of these measurements are used to develop and tune models for soft particle production.

  12. Auto-production of biosurfactants reverses the coffee ring effect in a bacterial system

    OpenAIRE

    Sempels, Wouter; De Dier, Raf; Mizuno, Hideaki; Hofkens, Johan; Vermant, Jan

    2013-01-01

    The deposition of material at the edge of evaporating droplets, known as the ‘coffee ring effect’, is caused by a radially outward capillary flow. This phenomenon is common to a wide array of systems including colloidal and bacterial systems. The role of surfactants in counteracting these coffee ring depositions is related to the occurrence of local vortices known as Marangoni eddies. Here we show that these swirling flows are universal, and not only lead to a uniform deposition of colloids b...

  13. Populations of Stored Product Mite Tyrophagus putrescentiae Differ in Their Bacterial Communities

    Science.gov (United States)

    Erban, Tomas; Klimov, Pavel B.; Smrz, Jaroslav; Phillips, Thomas W.; Nesvorna, Marta; Kopecky, Jan; Hubert, Jan

    2016-01-01

    Background: Tyrophagus putrescentiae colonizes different human-related habitats and feeds on various post-harvest foods. The microbiota acquired by these mites can influence the nutritional plasticity in different populations. We compared the bacterial communities of five populations of T. putrescentiae and one mixed population of T. putrescentiae and T. fanetzhangorum collected from different habitats. Material: The bacterial communities of the six mite populations from different habitats and diets were compared by Sanger sequencing of cloned 16S rRNA obtained from amplification with universal eubacterial primers and using bacterial taxon-specific primers on the samples of adults/juveniles or eggs. Microscopic techniques were used to localize bacteria in food boli and mite bodies. The morphological determination of the mite populations was confirmed by analyses of CO1 and ITS fragment genes. Results: The following symbiotic bacteria were found in compared mite populations: Wolbachia (two populations), Cardinium (five populations), Bartonella-like (five populations), Blattabacterium-like symbiont (three populations), and Solitalea-like (six populations). From 35 identified OTUs97, only Solitalea was identified in all populations. The next most frequent and abundant sequences were Bacillus, Moraxella, Staphylococcus, Kocuria, and Microbacterium. We suggest that some bacterial species may occasionally be ingested with food. The bacteriocytes were observed in some individuals in all mite populations. Bacteria were not visualized in food boli by staining, but bacteria were found by histological means in ovaria of Wolbachia-infested populations. Conclusion: The presence of Blattabacterium-like, Cardinium, Wolbachia, and Solitalea-like in the eggs of T. putrescentiae indicates mother to offspring (vertical) transmission. Results of this study indicate that diet and habitats influence not only the ingested bacteria but also the symbiotic bacteria of T. putrescentiae. PMID

  14. Evaluation of effectiveness of bacterial product which can degrade pesticide-dimethoate on the scale of true practice test

    International Nuclear Information System (INIS)

    Dimethoate, an organophosphate pesticide has been widely used in Dalat, Lamdong. It is much toxic to birds, human being and other mammals. Its widespread use has caused environmental concern on the basic of frequent detection of dimethoate in soil and water. Microorganisms are key agents in the degradation of waste, oil and a vast array of organic pesticide in terrestrial and aquatic ecosystems. In previous study, bacteria products which can degrade. Dimethoate were produced. The present study was designed to evaluate the effectiveness of bacterial product which can degrade Pesticide-Dimethoate on the scale of true practice test. The results indicated that application bacteria product to soil grown with Cauliflower and Chinese Cabbage sprayed with organic phosphorus pesticides (Dimethoate and Chloropyrifos), the pesticide residues in soil, water and vegetables were as follow: The residues of Dimethoate and Chloropyrifos in soil grown with Cauliflower, Chinese cabbages are different. They concentrated mostly in the surface litter and top soil layers with the depth from 0 to 20 cm. From the depth of 20 cm to 100 cm, the pesticide residues were ignorable. Residue of Chloropyrifos in soil was small as well. Dimethoate residues in soil grown with Cauliflower were higher than that of Chinese cabbages. On the basis of the environmental criteria of Ministry for Science, Technology and Environment (6/95), Dimethoate residues in soil grown with cauliflowers were in excess of the maximum limit. In the case of using bacteria product to soil, pesticide residues in soil were decreased. The results also indicated that Chloropyrifos residues in water (water obtained at the depth of 75 cm and 100 cm by days) were small. Residue of Dimethoate in water small. Residue of Dimethoate in water obtained from the Cauliflower bed were higher than of Chinese cabbages one. Using bacteria product to soil, pesticide residues in water decreased. On the basis of the environmental criteria of

  15. Production of putrescine-capped stable silver nanoparticle: its characterization and antibacterial activity against multidrug-resistant bacterial strains

    Science.gov (United States)

    Saha, Saswati; Gupta, Bhaskar; Gupta, Kamala; Chaudhuri, Mahua Ghosh

    2016-04-01

    Integration of biology with nanotechnology is now becoming attention-grabbing area of research. The antimicrobial potency of silver has been eminent from antiquity. Due to the recent desire for the enhancement of antibacterial efficacy of silver, various synthesis methods of silver in their nano dimensions are being practiced using a range of capping material. The present work highlights a facile biomimetic approach for production of silver nanoparticle being capped and stabilized by putrescine, possessing a diameter of 10-25 ± 1.5 nm. The synthesized nanoparticles have been analyzed spectrally and analytically. Morphological studies are carried out by high-resolution transmission electron microscopy and crystallinity by selected area electron diffraction patterns. Moreover, the elemental composition of the capped nanoparticles was confirmed by energy-dispersive X-ray spectroscopy analysis. A comparative study (zone of inhibition and minimum inhibitory concentration) regarding the interactions and antibacterial potentiality of the capped silver nanoparticles with respect to the bare ones reveal the efficiency of the capped one over the bare one. The bacterial kinetic study was executed to monitor the interference of nanoparticles with bacterial growth rate. The results also highlight the efficacy of putrescine-capped silver nanoparticles as effective growth inhibitors against multi-drug resistant human pathogenic bacterial strains, which may, thus, potentially be applicable as an effective antibacterial control system to fight diseases.

  16. Effect of Cultivation Time and Medium Condition in Production of Bacterial Cellulose Nanofiber for Urease Immobilization

    Directory of Open Access Journals (Sweden)

    M. Pesaran

    2015-01-01

    Full Text Available A new nanoporous biomatrix originated from bacterial resources has been chosen for urease immobilization. Urease has been immobilized on synthesized bacterial cellulose nanofiber since this enzyme has a key role in nitrogen metabolism. Gluconacetobacter xylinum ATCC 10245 has been cultivated for synthesis of a nanofiber with the diameter of 30–70 nm. Different cultivation processes in the aspect of time and cultivation medium conditions were chosen to study the performance of immobilized enzyme on four types of bacterial cellulose nanofibers (BCNs. Urease immobilization into the nanofiber has been done in two steps: enzyme adsorption and glutaraldehyde cross-linking. The results showed that the immobilized enzymes were relatively active and highly stable compared to the control samples of free enzymes. Optimum pH was obtained 6.5 and 7 for different synthesized BCNs, while the optimum temperature for immobilized urease was 50°C. Finding of the current experiment illustrated that the immobilized enzyme in optimum condition lost its initial activity by 41% after 15 weeks.

  17. Characterization of corrosive bacterial consortia isolated from petroleum-product-transporting pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Rajasekar, Aruliah; Ting, Yen-Peng [National Univ. of Singapore (Singapore). Dept. of Chemical and Biomolecular Engineering; Anandkumar, Balakrishnan [Sourashtra Coll., Madurai (India). Dept. of Biotechnology; Maruthamuthu, Sundaram [Central Electrochemical Research Inst., Karaikudi (India). Biocorrosion Group; Rahman, Pattanathu K.S.M. [Teesside Univ., Tees Valley (United Kingdom). Chemical and Bioprocess Engineering Group

    2010-01-15

    Microbiologically influenced corrosion is a problem commonly encountered in facilities in the oil and gas industries. The present study describes bacterial enumeration and identification in diesel and naphtha pipelines located in the northwest and southwest region in India, using traditional cultivation technique and 16S rDNA gene sequencing. Phylogenetic analysis of 16S rRNA sequences of the isolates was carried out, and the samples obtained from the diesel and naphtha-transporting pipelines showed the occurrence of 11 bacterial species namely Serratia marcescens ACE2, Bacillus subtilis AR12, Bacillus cereus ACE4, Pseudomonas aeruginosa AI1, Klebsiella oxytoca ACP, Pseudomonas stutzeri AP2, Bacillus litoralis AN1, Bacillus sp., Bacillus pumilus AR2, Bacillus carboniphilus AR3, and Bacillus megaterium AR4. Sulfate-reducing bacteria were not detected in samples from both pipelines. The dominant bacterial species identified in the petroleum pipeline samples were B. cereus and S. marcescens in the diesel and naphtha pipelines, respectively. Therefore, several types of bacteria may be involved in biocorrosion arising from natural biofilms that develop in industrial facilities. In addition, localized (pitting) corrosion of the pipeline steel in the presence of the consortia was observed by scanning electron microscopy analysis. The potential role of each species in biofilm formation and steel corrosion is discussed. (orig.)

  18. Overexpression of bacterial ethylene-forming enzyme gene in Trichoderma reesei enhanced the production of ethylene

    Directory of Open Access Journals (Sweden)

    Xi Chen, Yong Liang, Jing Hua, Li Tao, Wensheng Qin, Sanfeng Chen

    2010-01-01

    Full Text Available In order to efficiently utilize natural cellulose materials to produce ethylene, three expression vectors containing the ethylene-forming enzyme (efe gene from Pseudomonas syringae pv. glycinea were constructed. The target gene was respectively controlled by different promoters: cbh I promoter from Trichoderma reesei cellobiohydrolases I gene, gpd promoter from Aspergillus nidulans glyceraldehyde-3-phosphate dehydrogenase gene and pgk I promoter from T. reesei 3-phosphoglycerate kinase I gene. After transforming into T. reesei QM9414, 43 stable transformants were obtained by PCR amplification and ethylene determination. Southern blot analysis of 14 transformants demonstrated that the efe gene was integrated into chromosomal DNA with copy numbers from 1 to 4. Reverse transcription polymerase chain reaction (RT-PCR analysis of 6 transformants showed that the heterologous gene was transcribed. By using wheat straw as a carbon source, the ethylene production rates of aforementioned 14 transformants were measured. Transformant C30-3 with pgk I promoter had the highest ethylene production (4,012 nl h-1 l-1. This indicates that agricultural wastes could be used to produce ethylene in recombinant filamentous fungus T. reesei.

  19. Manipulating the glycosylation pathway in bacterial and lower eukaryotes for production of therapeutic proteins

    DEFF Research Database (Denmark)

    Anyaogu, Diana Chinyere; Mortensen, Uffe Hasbro

    2015-01-01

    The medical use of pharmaceutical proteins is rapidly increasing and cheap, fast and efficient production is therefore attractive. Microbial production hosts are promising candidates for development and production of pharmaceutical proteins. However, as most therapeutic proteins are secreted prot...

  20. Nonstarch polysaccharides modulate bacterial microbiota, pathways for butyrate production, and abundance of pathogenic Escherichia coli in the pig gastrointestinal tract.

    Science.gov (United States)

    Metzler-Zebeli, Barbara U; Hooda, Seema; Pieper, Robert; Zijlstra, Ruurd T; van Kessel, Andrew G; Mosenthin, Rainer; Gänzle, Michael G

    2010-06-01

    The impact of nonstarch polysaccharides (NSP) differing in their functional properties on intestinal bacterial community composition, prevalence of butyrate production pathway genes, and occurrence of Escherichia coli virulence factors was studied for eight ileum-cannulated growing pigs by use of terminal restriction fragment length polymorphism (TRFLP) and quantitative PCR. A cornstarch- and casein-based diet was supplemented with low-viscosity, low-fermentability cellulose (CEL), with high-viscosity, low-fermentability carboxymethylcellulose (CMC), with low-viscosity, high-fermentability oat beta-glucan (LG), and with high-viscosity, high-fermentability oat beta-glucan (HG). Only minor effects of NSP fractions on the ileal bacterial community were observed, but NSP clearly changed the digestion in the small intestine. Compared to what was observed for CMC, more fermentable substrate was transferred into the large intestine with CEL, LG, and HG, resulting in higher levels of postileal dry-matter disappearance. Linear discriminant analysis of NSP and TRFLP profiles and 16S rRNA gene copy numbers for major bacterial groups revealed that CMC resulted in a distinctive bacterial community in comparison to the other NSP, which was characterized by higher gene copy numbers for total bacteria, Bacteroides-Prevotella-Porphyromonas, Clostridium cluster XIVa, and Enterobacteriaceae and increased prevalences of E. coli virulence factors in feces. The numbers of butyryl-coenzyme A (CoA) CoA transferase gene copies were higher than those of butyrate kinase gene copies in feces, and these quantities were affected by NSP. The present results suggest that the NSP fractions clearly and distinctly affected the taxonomic composition and metabolic features of the fecal microbiota. However, the effects were more linked to the individual NSP and to their effect on nutrient flow into the large intestine than to their shared functional properties.

  1. Use of Response Surface Methodology to Optimize Culture Conditions for Hydrogen Production by an Anaerobic Bacterial Strain from Soluble Starch

    Science.gov (United States)

    Kieu, Hoa Thi Quynh; Nguyen, Yen Thi; Dang, Yen Thi; Nguyen, Binh Thanh

    2016-05-01

    Biohydrogen is a clean source of energy that produces no harmful byproducts during combustion, being a potential sustainable energy carrier for the future. Therefore, biohydrogen produced by anaerobic bacteria via dark fermentation has attracted attention worldwide as a renewable energy source. However, the hydrogen production capability of these bacteria depends on major factors such as substrate, iron-containing hydrogenase, reduction agent, pH, and temperature. In this study, the response surface methodology (RSM) with central composite design (CCD) was employed to improve the hydrogen production by an anaerobic bacterial strain isolated from animal waste in Phu Linh, Soc Son, Vietnam (PL strain). The hydrogen production process was investigated as a function of three critical factors: soluble starch concentration (8 g L-1 to 12 g L-1), ferrous iron concentration (100 mg L-1 to 200 mg L-1), and l-cysteine concentration (300 mg L-1 to 500 mg L-1). RSM analysis showed that all three factors significantly influenced hydrogen production. Among them, the ferrous iron concentration presented the greatest influence. The optimum hydrogen concentration of 1030 mL L-1 medium was obtained with 10 g L-1 soluble starch, 150 mg L-1 ferrous iron, and 400 mg L-1 l-cysteine after 48 h of anaerobic fermentation. The hydrogen concentration produced by the PL strain was doubled after using RSM. The obtained results indicate that RSM with CCD can be used as a technique to optimize culture conditions for enhancement of hydrogen production by the selected anaerobic bacterial strain. Hydrogen production from low-cost organic substrates such as soluble starch using anaerobic fermentation methods may be one of the most promising approaches.

  2. Muramic Acid Measurements for Bacterial Investigations in Marine Environments by High-Pressure Liquid Chromatography

    OpenAIRE

    Mimura, Toru; Romano, Jean-Claude

    1985-01-01

    Muramic acid, a constituent of procaryotic cell walls, was assayed by high-pressure liquid chromatography in samples from several marine environments (water column, surface microlayer, and sediment) and a bacterial culture. It is used as a microbial biomass indicator. The method gave a good separation of muramic acid from interfering compounds with satisfactory reproducibility. A pseudomonad culture had a muramic acid content of 4.7 × 10−10 to 5.3 × 10−10 μg per cell during growth. In natural...

  3. Measurement of inelastic charmonium production at HERA

    International Nuclear Information System (INIS)

    This thesis presents measurements of inelastic photoproduction and electroproduction of J/Ψ mesons in ep scattering at HERA. The data was collected by the H1 detector during the HERA II running and corresponds to an integrated luminosity of L ∼ 166 pb-1 in the photoproduction analysis and L ∼ 315 pb-1 in the electroproduction analysis. In both analyses the elasticity of the J/Ψ meson is restricted to a medium range of 0.3 ≤ z ≤ 0.9. The kinematic range of the photoproduction analysis is defined by Q2 ∼ 0 GeV2, 60 ≤Wγp≤ 240 GeV and PΤ,Ψ≥ 1 GeV2, whereas the electroproduction analysis is restricted to 3.6 ≤ Q2 ≤ 100 GeV2, 50 ≤Wγp≤ 225 GeV, and P*Τ,Ψ ≥ 1 GeV. Here P*Τ,Ψ denotes the transverse momentum of the J/Ψ in the γp center of mass frame. In both kinematic ranges, single differential and double differential cross sections are measured with increased precision with respect to previous analyses. The polarisation of the J/Ψ mesons is studied in fits to the decay angular distributions cos(Θ*) and φ*. The measured cross sections are compared to different theoretical predictions. The most successful calculation in describing the data accounts for higher order corrections by using a kΤ factorisation ansatz in the color singlet model (CSM). In addition, this thesis reviews the description of the data by calculations at leading and next to leading order in the CSM. The polarisation variables are compared to calculations in the factorisation ansatz in NRQCD, in addition to the leading order CSM predictions. (orig.)

  4. A hybrid DNA extraction method for the qualitative and quantitative assessment of bacterial communities from poultry production samples.

    Science.gov (United States)

    Rothrock, Michael J; Hiett, Kelli L; Gamble, John; Caudill, Andrew C; Cicconi-Hogan, Kellie M; Caporaso, J Gregory

    2014-01-01

    The efficacy of DNA extraction protocols can be highly dependent upon both the type of sample being investigated and the types of downstream analyses performed. Considering that the use of new bacterial community analysis techniques (e.g., microbiomics, metagenomics) is becoming more prevalent in the agricultural and environmental sciences and many environmental samples within these disciplines can be physiochemically and microbiologically unique (e.g., fecal and litter/bedding samples from the poultry production spectrum), appropriate and effective DNA extraction methods need to be carefully chosen. Therefore, a novel semi-automated hybrid DNA extraction method was developed specifically for use with environmental poultry production samples. This method is a combination of the two major types of DNA extraction: mechanical and enzymatic. A two-step intense mechanical homogenization step (using bead-beating specifically formulated for environmental samples) was added to the beginning of the "gold standard" enzymatic DNA extraction method for fecal samples to enhance the removal of bacteria and DNA from the sample matrix and improve the recovery of Gram-positive bacterial community members. Once the enzymatic extraction portion of the hybrid method was initiated, the remaining purification process was automated using a robotic workstation to increase sample throughput and decrease sample processing error. In comparison to the strict mechanical and enzymatic DNA extraction methods, this novel hybrid method provided the best overall combined performance when considering quantitative (using 16S rRNA qPCR) and qualitative (using microbiomics) estimates of the total bacterial communities when processing poultry feces and litter samples. PMID:25548939

  5. Integrated Productivity Accounts: Contributions to the Measurement of Capital

    OpenAIRE

    MacDonald, Ryan; Gu, Wulong; Baldwin, John R.

    2010-01-01

    Measures of productivity are derived by comparing outputs and inputs. The System of National Accounts (SNA) in Canada provides a useful framework for organizing the information required for comparisons of this type. Integrated systems of economic accounts provide coherent, consistent alternate estimates of the various concepts that can be used to measure productivity.

  6. Measurement of inelastic charmonium production at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Steder, Michael

    2008-09-15

    This thesis presents measurements of inelastic photoproduction and electroproduction of J/{psi} mesons in ep scattering at HERA. The data was collected by the H1 detector during the HERA II running and corresponds to an integrated luminosity of L {approx} 166 pb{sup -1} in the photoproduction analysis and L {approx} 315 pb{sup -1} in the electroproduction analysis. In both analyses the elasticity of the J/{psi} meson is restricted to a medium range of 0.3 {<=} z {<=} 0.9. The kinematic range of the photoproduction analysis is defined by Q{sup 2} {approx} 0 GeV{sup 2}, 60 {<=}W{sub {gamma}}{sub p}{<=} 240 GeV and P{sub {tau}}{sub ,{psi}}{>=} 1 GeV{sup 2}, whereas the electroproduction analysis is restricted to 3.6 {<=} Q{sup 2} {<=} 100 GeV{sup 2}, 50 {<=}W{sub {gamma}}{sub p}{<=} 225 GeV, and P{sup *}{sub {tau}}{sub ,} {sub {psi}} {>=} 1 GeV. Here P{sup *}{sub {tau}}{sub ,} {sub {psi}} denotes the transverse momentum of the J/{psi} in the {gamma}p center of mass frame. In both kinematic ranges, single differential and double differential cross sections are measured with increased precision with respect to previous analyses. The polarisation of the J/{psi} mesons is studied in fits to the decay angular distributions cos({theta}{sup *}) and {phi}{sup *}. The measured cross sections are compared to different theoretical predictions. The most successful calculation in describing the data accounts for higher order corrections by using a k{sub {tau}} factorisation ansatz in the color singlet model (CSM). In addition, this thesis reviews the description of the data by calculations at leading and next to leading order in the CSM. The polarisation variables are compared to calculations in the factorisation ansatz in NRQCD, in addition to the leading order CSM predictions. (orig.)

  7. Manipulating the glycosylation pathway in bacterial and lower eukaryotes for production of therapeutic proteins.

    Science.gov (United States)

    Anyaogu, Diana Chinyere; Mortensen, Uffe Hasbro

    2015-12-01

    The medical use of pharmaceutical proteins is rapidly increasing and cheap, fast and efficient production is therefore attractive. Microbial production hosts are promising candidates for development and production of pharmaceutical proteins. However, as most therapeutic proteins are secreted proteins, they are frequently N-glycosylated. This hampers production in microbes as these hosts glycosylate proteins differently. The resulting products may therefore be immunogenic, unstable and show reduced efficacy. Recently, successful glycoengineering of microbes has demonstrated that it is possible to produce proteins with humanlike glycan structures setting the stage for production of pharmaceutical proteins in bacteria, yeasts and algae.

  8. Multi-parameter flow cytometry as a process analytical technology (PAT) approach for the assessment of bacterial ghost production.

    Science.gov (United States)

    Langemann, Timo; Mayr, Ulrike Beate; Meitz, Andrea; Lubitz, Werner; Herwig, Christoph

    2016-01-01

    Flow cytometry (FCM) is a tool for the analysis of single-cell properties in a cell suspension. In this contribution, we present an improved FCM method for the assessment of E-lysis in Enterobacteriaceae. The result of the E-lysis process is empty bacterial envelopes-called bacterial ghosts (BGs)-that constitute potential products in the pharmaceutical field. BGs have reduced light scattering properties when compared with intact cells. In combination with viability information obtained from staining samples with the membrane potential-sensitive fluorescent dye bis-(1,3-dibutylarbituric acid) trimethine oxonol (DiBAC4(3)), the presented method allows to differentiate between populations of viable cells, dead cells, and BGs. Using a second fluorescent dye RH414 as a membrane marker, non-cellular background was excluded from the data which greatly improved the quality of the results. Using true volumetric absolute counting, the FCM data correlated well with cell count data obtained from colony-forming units (CFU) for viable populations. Applicability of the method to several Enterobacteriaceae (different Escherichia coli strains, Salmonella typhimurium, Shigella flexneri 2a) could be shown. The method was validated as a resilient process analytical technology (PAT) tool for the assessment of E-lysis and for particle counting during 20-l batch processes for the production of Escherichia coli Nissle 1917 BGs.

  9. Top production measurements using the ATLAS detector at the LHC

    CERN Document Server

    Romano, Marino; The ATLAS collaboration

    2015-01-01

    Measurements of the inclusive and differential top quark pair and singletop production cross sections in proton-proton collisions with the ATLAS detector at the Large Hadron Collider are presented. The inclusive measurements reach high precision and are compared to the best available theoretical calculations. Differential measurements of the kinematic properties of the top quark production are also discussed. These measurements, including results using boosted tops, probe our understanding of top pair production in the TeV regime. The results, unfolded to particle and parton level, are compared to Monte Carlo generators implementing LO and NLO matrix elements matched with parton showers and NLO QCD calculations.

  10. Salmonella Infection Enhances Erythropoietin Production by the Kidney and Liver, Which Correlates with Elevated Bacterial Burdens.

    Science.gov (United States)

    Li, Lin-Xi; Benoun, Joseph M; Weiskopf, Kipp; Garcia, K Christopher; McSorley, Stephen J

    2016-10-01

    Salmonella infection profoundly affects host erythroid development, but the mechanisms responsible for this effect remain poorly understood. We monitored the impact of Salmonella infection on erythroid development and found that systemic infection induced anemia, splenomegaly, elevated erythropoietin (EPO) levels, and extramedullary erythropoiesis in a process independent of Salmonella pathogenicity island 2 (SPI2) or flagellin. The circulating EPO level was also constitutively higher in mice lacking the expression of signal-regulatory protein α (SIRPα). The expression level of EPO mRNA was elevated in the kidney and liver but not increased in the spleens of infected mice despite the presence of extramedullary erythropoiesis in this tissue. In contrast to data from a previous report, mice lacking EPO receptor (EPOR) expression on nonerythroid cells (EPOR rescued) had bacterial loads similar to those of wild-type mice following Salmonella infection. Indeed, treatment to reduce splenic erythroblasts and mature red blood cells correlated with elevated bacterial burdens, implying that extramedullary erythropoiesis benefits the host. Together, these findings emphasize the profound effect of Salmonella infection on erythroid development and suggest that the modulation of erythroid development has both positive and negative consequences for host immunity.

  11. Engineering bacterial biopolymers for the biosorption of heavy metals; new products and novel formulations

    International Nuclear Information System (INIS)

    Bioremediation of heavy metal pollution remains a major challenge in environmental biotechnology. One of the approaches considered for application involves biosorption either to biomass or to isolated biopolymers. Many bacterial polysaccharides have been shown to bind heavy metals with varying degrees of specificity and affinity. While various approaches have been adopted to generate polysaccharide variants altered in both structure and activity, metal biosorption has not been examined. Polymer engineering has included structural modification through the introduction of heterologous genes of the biosynthetic pathway into specific mutants, leading either to alterations in polysaccharide backbone or side chains, or to sugar modification. In addition, novel formulations can be designed which enlarge the family of available bacterial biopolymers for metal-binding and subsequent recovery. An example discussed here is the use of amphipathic bioemulsifiers such as emulsan, produced by the oil-degrading Acinetobacter lwoffii RAG-1, that forms stable, concentrated (70%), oil-in-water emulsions (emulsanosols). In this system metal ions bind primarily at the oil/water interface, enabling their recovery and concentration from relatively dilute solutions. In addition to the genetic modifications described above, a new approach to the generation of amphipathic bioemulsifying formulations is based on the interaction of native or recombinant esterase and its derivatives with emulsan and other water-soluble biopolymers. Cation-binding emulsions are generated from a variety of hydrophobic substrates. The features of these and other systems will be discussed, together with a brief consideratiton of possible applications. (orig.)

  12. Engineering bacterial biopolymers for the biosorption of heavy metals; new products and novel formulations

    Energy Technology Data Exchange (ETDEWEB)

    Gutnick, D.L.; Bach, H. [Tel-Aviv Univ. (Israel). Dept. of Molecular Microbiology and Biotechnology

    2000-07-01

    Bioremediation of heavy metal pollution remains a major challenge in environmental biotechnology. One of the approaches considered for application involves biosorption either to biomass or to isolated biopolymers. Many bacterial polysaccharides have been shown to bind heavy metals with varying degrees of specificity and affinity. While various approaches have been adopted to generate polysaccharide variants altered in both structure and activity, metal biosorption has not been examined. Polymer engineering has included structural modification through the introduction of heterologous genes of the biosynthetic pathway into specific mutants, leading either to alterations in polysaccharide backbone or side chains, or to sugar modification. In addition, novel formulations can be designed which enlarge the family of available bacterial biopolymers for metal-binding and subsequent recovery. An example discussed here is the use of amphipathic bioemulsifiers such as emulsan, produced by the oil-degrading Acinetobacter lwoffii RAG-1, that forms stable, concentrated (70%), oil-in-water emulsions (emulsanosols). In this system metal ions bind primarily at the oil/water interface, enabling their recovery and concentration from relatively dilute solutions. In addition to the genetic modifications described above, a new approach to the generation of amphipathic bioemulsifying formulations is based on the interaction of native or recombinant esterase and its derivatives with emulsan and other water-soluble biopolymers. Cation-binding emulsions are generated from a variety of hydrophobic substrates. The features of these and other systems will be discussed, together with a brief consideratiton of possible applications. (orig.)

  13. Near-infrared spectroscopy for the detection and quantification of bacterial contaminations in pharmaceutical products.

    Science.gov (United States)

    Quintelas, Cristina; Mesquita, Daniela P; Lopes, João A; Ferreira, Eugénio C; Sousa, Clara

    2015-08-15

    Accurate detection and quantification of microbiological contaminations remains an issue mainly due the lack of rapid and precise analytical techniques. Standard methods are expensive and time-consuming being associated to high economic losses and public health threats. In the context of pharmaceutical industry, the development of fast analytical techniques able to overcome these limitations is crucial and spectroscopic techniques might constitute a reliable alternative. In this work we proved the ability of Fourier transform near infrared spectroscopy (FT-NIRS) to detect and quantify bacteria (Bacillus subtilis, Escherichia coli, Pseudomonas fluorescens, Salmonella enterica, Staphylococcus epidermidis) from 10 to 10(8) CFUs/mL in sterile saline solutions (NaCl 0.9%). Partial least squares discriminant analysis (PLSDA) models showed that FT-NIRS was able to discriminate between sterile and contaminated solutions for all bacteria as well as to identify the contaminant bacteria. Partial least squares (PLS) models allowed bacterial quantification with limits of detection ranging from 5.1 to 9 CFU/mL for E. coli and B. subtilis, respectively. This methodology was successfully validated in three pharmaceutical preparations (contact lens solution, cough syrup and topic anti-inflammatory solution) proving that this technique possess a high potential to be routinely used for the detection and quantification of bacterial contaminations. PMID:26151105

  14. Effects of different fermentation methods on bacterial cellulose and acid production by Gluconacetobacter xylinus in Cantonese-style rice vinegar.

    Science.gov (United States)

    Fu, Liang; Chen, Siqian; Yi, Jiulong; Hou, Zongxia

    2014-07-01

    A strain of acidogenic bacterium was isolated from the fermentation liquid of Cantonese-style rice vinegar produced by traditional surface fermentation. 16S rDNA identification confirmed the bacterium as Gluconacetobacter xylinus, which synthesizes bacterial cellulose, and the acid productivity of the strain was investigated. In the study, the effects of the membrane integrity and the comparison of the air-liquid interface membrane with immerged membrane on total acidity, cellulose production, alcohol dehydrogenase (ADH) activity and number of bacteria were investigated. The cellulose membrane and the bacteria were observed under SEM for discussing their relationship. The correlations between oxygen consumption and total acid production rate were compared in surface and shake flask fermentation. The results showed the average acid productivity of the strain was 0.02g/(100mL/h), and the integrity of cellulose membrane in surface fermentation had an important effect on total acidity and cellulose production. With a higher membrane integrity, the total acidity after 144 h of fermentation was 3.75 g/100 mL, and the cellulose production was 1.71 g/100 mL after 360 h of fermentation. However, when the membrane was crushed by mechanical force, the total acidity and the cellulose production were as low as 0.36 g/100 mL and 0.14 g/100 mL, respectively. When the cellulose membrane was forced under the surface of fermentation liquid, the total acid production rate was extremely low, but the activity of ADH in the cellulose membrane was basically the same with the one above the liquid surface. The bacteria were mainly distributed in the cellulose membrane during the fermentation. The bacterial counts in surface fermentation were more than in the shake flask fermentation and G. xylinus consumed the substrate faster, in surface fermentation than in shake flask fermentation. The oxygen consumption rate and total acid production rate of surface fermentation were respectively 26

  15. Nanomaterial-based sensors for detection of foodborne bacterial pathogens and toxins as well as pork adulteration in meat products

    Directory of Open Access Journals (Sweden)

    B. Stephen Inbaraj

    2016-01-01

    Full Text Available Food safety draws considerable attention in the modern pace of the world owing to rapid-changing food recipes and food habits. Foodborne illnesses associated with pathogens, toxins, and other contaminants pose serious threat to human health. Besides, a large amount of money is spent on both analyses and control measures, which causes significant loss to the food industry. Conventional detection methods for bacterial pathogens and toxins are time consuming and laborious, requiring certain sophisticated instruments and trained personnel. In recent years, nanotechnology has emerged as a promising field for solving food safety issues in terms of detecting contaminants, enabling controlled release of preservatives to extend the shelf life of foods, and improving food-packaging strategies. Nanomaterials including metal oxide and metal nanoparticles, carbon nanotubes, and quantum dots are gaining a prominent role in the design of sensors and biosensors for food analysis. In this review, various nanomaterial-based sensors reported in the literature for detection of several foodborne bacterial pathogens and toxins are summarized highlighting their principles, advantages, and limitations in terms of simplicity, sensitivity, and multiplexing capability. In addition, the application through a noncross-linking method without the need for any surface modification is also presented for detection of pork adulteration in meat products.

  16. Measures for Increasing of Company’s Production Capacity

    Directory of Open Access Journals (Sweden)

    Ernesta Žikevičiūtė

    2012-07-01

    Full Text Available Production capacity improvements are poorly explored areas of economic literature and the existing methods are difficult to apply. For this reason, the organization has only a superficial analysis of capacity, but after all this time, each production company had to improve the production capacity for the market economy and the most economical use of production factors.This article explores the company’s production capacity for better use of tools. It also presents the capacity of their concept, establishment, evaluates the factors leading to their production capacity, for developing efficiency measures and model presentation.Article in Lithuanian

  17. Optimization of rhamnolipid production by biodegrading bacterial isolates using Plackett-Burman design.

    Science.gov (United States)

    Hassan, Mariam; Essam, Tamer; Yassin, Aymen S; Salama, Aisha

    2016-01-01

    Biosurfactants are biological surfactants produced by microorganisms. Pseudomonas species are well known for the production of the rhamnolipid biosurfactant. In this work, the production of rhamnolipid biosurfactant by Pseudomonas spp. was investigated and further optimized. Two Plackett-Burman designs to study the effect of carbon source, nitrogen source, C/N ratio, iron concentration, magnesium concentration, phenol toxicity, pH, temperature, agitation and sampling time were tested. The first design revealed an optimization that increased biosurfactant productivity by almost two to fivefolds for the tested isolates. However, using the second design showed no remarkable increase in biosurfactant productivity. An additional validation run was adopted using the predicted optimal medium with predicted optimal conditions. The validation run showed remarkable increase in the productivity of the tested isolates. The use of microorganisms with biodegradation ability coupled with optimization of the parameters affecting productivity provides an efficient strategy for biosurfactant production.

  18. Implications of energy efficiency measures in wheat production

    DEFF Research Database (Denmark)

    Meyer-Aurich, Andreas; Ziegler, T.; Scholz, L.;

    The economic and environmental effect of energy saving measures were analyzed for a typical wheat production system in Germany. The introduction of precision farming, reduced nitrogen fertilization and improved crop drying technologies proved to be efficient measures for enhancing energy efficiency...... in wheat production. While the measures precision farming and improved crop drying require investments, reduced fertilizer input can be realized without investments. The environmental effects of all measures are comparable and do not show a clear advantage of one measure against the others. However......, reduced fertilizer input implies an economic loss which is unlikely to be realized by farmers unless they are forced to do so....

  19. Incomplete aerobic degradation of the antidiabetic drug Metformin and identification of the bacterial dead-end transformation product Guanylurea.

    Science.gov (United States)

    Trautwein, Christoph; Kümmerer, Klaus

    2011-10-01

    Active pharmaceutical ingredients as well as personal care products are detected in increasing prevalence in different environmental compartments such as surface water, groundwater and soil. Still little is known about the environmental fate of these substances. The type II antidiabetic drug Metformin has already been detected in different surface waters worldwide, but concentrations were significantly lower than the corresponding predicted environmental concentration (PEC). In human and mammal metabolism so far no metabolites of Metformin have been identified, so the expected environmental concentrations should be very high. To assess the aerobic biodegradability of Metformin and the possible formation of degradation products, three Organisation of Economic Cooperation and Development (OECD) test series were performed in the present study. In the Closed Bottle test (OECD 301 D), a screening test that simulates the conditions of an environmental surface water compartment, Metformin was classified as not readily biodegradable (no biodegradation). In the Manometric Respiratory test (OEDC 301 F) working with high bacterial density, Metformin was biodegraded in one of three test bottles to 48.7% and in the toxicity control bottle to 57.5%. In the Zahn-Wellens test (OECD 302 B) using activated sludge, Metformin was biodegraded in both test vessels to an extent of 51.3% and 49.9%, respectively. Analysis of test samples by high performance liquid chromatography coupled to multiple stage mass spectrometry (HPLC-MS(n)) showed in the tests vessels were biodegradation was observed full elimination of Metformin and revealed Guanylurea (Amidinourea, Dicyandiamidine) as single and stable aerobic bacterial degradation product. In another Manometric Respiratory test Guanylurea showed no more transformation. Photodegradation of Guanylurea was also negative. A first screening in one of the greatest sewage treatment plant in southern Germany found Metformin with high concentrations

  20. Measurements of photon and jet production properties with ATLAS

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00237016; The ATLAS collaboration

    2016-01-01

    Summary of recent ATLAS measurements of jet and photon production using proton–proton (pp) collisions from the Large Hadron Collider. The charged-particle multiplicity in jets, and jet charge measurements are presented using 8 TeV pp collisions. Differential measurements of jet and photon cross-sections are shown for 7, 8 and 13 TeV pp collisions.

  1. Measurements of photon and jet production properties with ATLAS

    CERN Document Server

    Meyer, Chris

    2016-01-01

    Summary of recent ATLAS measurements of jet and photon production using proton-proton (pp) collisions from the Large Hadron Collider. The charged-particle multiplicity in jets, and jet charge measurements are presented using 8 TeV pp collisions. Differential measurements of jet and photon cross-sections are shown for 7, 8 and 13 TeV pp collisions.

  2. Single-step production of a recyclable nanobiocatalyst for organophosphate pesticides biodegradation using functionalized bacterial magnetosomes.

    Directory of Open Access Journals (Sweden)

    Nicolas Ginet

    Full Text Available Enzymes are versatile catalysts in laboratories and on an industrial scale; improving their immobilization would be beneficial to broadening their applicability and ensuring their (reuse. Lipid-coated nano-magnets produced by magnetotactic bacteria are suitable for a universally applicable single-step method of enzyme immobilization. By genetically functionalizing the membrane surrounding these magnetite particles with a phosphohydrolase, we engineered an easy-to-purify, robust and recyclable biocatalyst to degrade ethyl-paraoxon, a commonly used pesticide. For this, we genetically fused the opd gene from Flavobacterium sp. ATCC 27551 encoding a paraoxonase to mamC, an abundant protein of the magnetosome membrane in Magnetospirillum magneticum AMB-1. The MamC protein acts as an anchor for the paraoxonase to the magnetosome surface, thus producing magnetic nanoparticles displaying phosphohydrolase activity. Magnetosomes functionalized with Opd were easily recovered from genetically modified AMB-1 cells: after cellular disruption with a French press, the magnetic nanoparticles are purified using a commercially available magnetic separation system. The catalytic properties of the immobilized Opd were measured on ethyl-paraoxon hydrolysis: they are comparable with the purified enzyme, with K(m (and k(cat values of 58 µM (and 178 s(-1 and 43 µM (and 314 s(-1 for the immobilized and purified enzyme respectively. The Opd, a metalloenzyme requiring a zinc cofactor, is thus properly matured in AMB-1. The recycling of the functionalized magnetosomes was investigated and their catalytic activity proved to be stable over repeated use for pesticide degradation. In this study, we demonstrate the easy production of functionalized magnetic nanoparticles with suitably genetically modified magnetotactic bacteria that are efficient as a reusable nanobiocatalyst for pesticides bioremediation in contaminated effluents.

  3. Measurements of inclusive vector boson production from ATLAS

    CERN Document Server

    Karnevskiy, M; The ATLAS collaboration

    2014-01-01

    The production of the W and Z bosons is the standard candle process at the LHC. Measurement of the transverse momentum of the Z boson performed by the ATLAS collaboration is reported for sqrt{s} = 7 TeV. The measurement is sensitive to soft resummation effects for small momentum transfers and to multiple hard jet emissions for large momentum transfers, probing QCD in a unique way. Measurements of the Drell-Yan production at low and high invariant masses are reported and compared to predictions based on NNLO QCD corrected for electroweak effects. A measurement of the lepton forward-­backward asymmetry for Z/gamma* production is used to determine the weak mixing angle. A measurement of the cross section for 4 lepton production near the Z resonance is presented for sqrt{s} = 7 and 8 TeV proton­-proton collisions recorded with the ATLAS experiment. An overview of these results is given.

  4. Associated J/$\\psi$ Production Measurements at ATLAS

    CERN Document Server

    Weinert, Benjamin; The ATLAS collaboration

    2016-01-01

    The associated production of quarkonium with a vector boson or an additional quarkonium state are rare processes that provide new insight into QCD models of quarkonium production, but also provide new opportunities to study double parton scattering. We present new measurements of J/psi production in association with a vector boson or another J/psi, in pp collisions at the ATLAS experiment. Differential production cross-sections of these processes are measured, and a data-driven approach is used to estimate the single parton scattering and double parton scattering contributions to these rates

  5. Associated $J/\\psi$ production measurements at ATLAS

    CERN Document Server

    Weinert, Benjamin; The ATLAS collaboration

    2016-01-01

    The associated production of quarkonium with a vector boson or an additional quarkonium state are rare processes that provide new insight into QCD models of quarkonium production, but also provide new opportunities to study double parton scattering. We present new measurements of $J/\\psi$ production in association with a vector boson or another $J/\\psi$, in $pp$ collisions using the ATLAS detector at the LHC. Differential production cross-sections of these processes are measured, and a data-driven approach is used to estimate the single parton scattering and double parton scattering contributions to these rates.

  6. Combining Overall equipment Efficiency (OEE) and productivity measures as drivers for production improvements

    OpenAIRE

    Andersson, Carin; Bellgran, Monica

    2011-01-01

    To compete on a globalized market companies need to constantly improve the performance in their manufacturing systems. Production performance measures can be used for different purposes, by practitioners they are commonly used for follow-up and reporting purposes. Two of the most commonly used performance measures are Overall Equipment Efficiency (OEE) and productivity. Between these two productivity exhibits the far most variety in definition. Even if OEE and productivity are strongly affect...

  7. Measuring productivity of customer knowledge management in projects

    OpenAIRE

    Tanika D. Sofianti; Kadarsah Suryadi; Rajesri Govindaraju; Budhi Prihartono

    2013-01-01

    Projects is one of the dominating modes of international business today. Companies interact with their customers in projects for a certain period. To explore the impact of customer knowledge management in such interactions, this paper promotes a measurement framework that can be used to measure the productivity of customer knowledge management. The measures are developed based on previous studies on customer knowledge management and project management. To verify the measures, this study condu...

  8. Biogas production from coumarin-rich plants--inhibition by coumarin and recovery by adaptation of the bacterial community.

    Science.gov (United States)

    Popp, Denny; Schrader, Steffi; Kleinsteuber, Sabine; Harms, Hauke; Sträuber, Heike

    2015-09-01

    Plants like sweet clover (Melilotus spp.) are not suitable as fodder for cattle because of harmful effects of the plant secondary metabolite coumarin. As an alternative usage, the applicability of coumarin-rich plants as substrates for biogas production was investigated. When coumarin was added to continuous fermentation processes codigesting grass silage and cow manure, it caused a strong inhibition noticeable as decrease of biogas production by 19% and increase of metabolite concentrations to an organic acids/alkalinity ratio higher than 0.3(gorganic acids) gCaCO3 (-1). Microbial communities of methanogenic archaea were dominated by the genera Methanosarcina (77%) and Methanoculleus (11%). This community composition was not influenced by coumarin addition. The bacterial community analysis unraveled a divergence caused by coumarin addition correlating with the anaerobic degradation of coumarin and the recovery of the biogas process. As a consequence, biogas production resumed similar to the coumarin-free control with a biogas yield of 0.34 LN g(volatile solids) (-1) and at initial metabolite concentrations (∼ 0.2 g(organic acids) gCaCO3 (-1)). Coumarin acts as inhibitor and as substrate during anaerobic digestion. Hence, coumarin-rich plants might be suitable for biogas production, but should only be used after adaptation of the microbial community to coumarin.

  9. Service Productivity How to Measure and Improve It?

    Science.gov (United States)

    den Hartigh, Erik; Zegveld, Marc

    Productivity is a key performance measure for service businesses and serves as a compass for measuring their innovativeness. In this chapter we present a tool for measuring productivity in service businesses. Improvements in service business productivity do not depend on industry, business size or business growth, but on the specific knowledge and competences of managers. Using case examples we show various ways of how managers can improve the productivity of their service businesses. They can do so by adopting a perspective of standardization, flexibility or individualization. Based on these perspectives, we provide a framework that shows how managers can improve service business productivity by coordinating strategic orientation, value creation and the configuration of business processes.

  10. Utilization of makgeolli sludge filtrate (MSF) as low-cost substrate for bacterial cellulose production by Gluconacetobacter xylinus.

    Science.gov (United States)

    Hyun, Jo Yi; Mahanty, Biswanath; Kim, Chang Gyun

    2014-04-01

    Search for efficient low-cost substrate/additives are gaining significant impetus in bacterial cellulose (BC) production. Makgeolli sludge (a traditional Korean wine distillery waste) is enriched with organic acid, alcohol, and sugar. Using makgeolli sludge filtrate (MSF) and Hestrin-Schramm (HS) medium (g/l of distilled water: glucose, 10.0; peptone, 5.0; yeast extract, 5.0; disodium phosphate, 2.7; citric acid, 1.15; pH 5.0), two different media-namely the modified HS media (ingredients of HS media except glucose dissolved in MSF) and mixed modified HS media (equal volume mixture of original and modified HS media)-were formulated. BC production with Gluconacetobacter xylinus was studied using the two above referred medium. Keeping HS medium as reference, effect of initial pH, glucose, ethanol, and organic acid concentration on BC production was also studied. It suggests that increasing initial glucose (up to 25 g/l) though improves BC production but results in poor BC yield above 15 g/l of glucose. However, addition of alcohol (up to 1%v/v) or citric acid (up to 20 mM) escalate productivity up to four and two times, respectively. In both modified HS media and mixed modified HS medium, BC production was four to five times higher than that of original HS medium. Even MSF alone surpassed HS medium in BC production. Scanning electron microscopy showed that BC microfibrils from MSF based media were several micrometers long and about 25-60 nm widths. X-ray diffraction patterns suggested the produced BC were of cellulose I polymorph.

  11. The SPIDER fission fragment spectrometer for fission product yield measurements

    Energy Technology Data Exchange (ETDEWEB)

    Meierbachtol, K.; Tovesson, F. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Shields, D. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Colorado School of Mines, Golden, CO 80401 (United States); Arnold, C. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Blakeley, R. [University of New Mexico, Albuquerque, NM 87131 (United States); Bredeweg, T.; Devlin, M. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Hecht, A.A.; Heffern, L.E. [University of New Mexico, Albuquerque, NM 87131 (United States); Jorgenson, J.; Laptev, A. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Mader, D. [University of New Mexico, Albuquerque, NM 87131 (United States); O' Donnell, J.M.; Sierk, A.; White, M. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2015-07-11

    The SPectrometer for Ion DEtermination in fission Research (SPIDER) has been developed for measuring mass yield distributions of fission products from spontaneous and neutron-induced fission. The 2E–2v method of measuring the kinetic energy (E) and velocity (v) of both outgoing fission products has been utilized, with the goal of measuring the mass of the fission products with an average resolution of 1 atomic mass unit (amu). The SPIDER instrument, consisting of detector components for time-of-flight, trajectory, and energy measurements, has been assembled and tested using {sup 229}Th and {sup 252}Cf radioactive decay sources. For commissioning, the fully assembled system measured fission products from spontaneous fission of {sup 252}Cf. Individual measurement resolutions were met for time-of-flight (250 ps FWHM), spacial resolution (2 mm FHWM), and energy (92 keV FWHM for 8.376 MeV). Mass yield results measured from {sup 252}Cf spontaneous fission products are reported from an E–v measurement.

  12. Production and characterization of nanospheres of bacterial cellulose from Acetobacter xylinum from processed rice bark

    Energy Technology Data Exchange (ETDEWEB)

    Goelzer, F.D.E. [Group of Industrial Microbiology, UNIVALI-Universidade do Vale do Itajai, R. Uruguai, 458, 88302-202, Itajai, Santa Catarina (Brazil); Faria-Tischer, P.C.S. [Group of Industrial Microbiology, UNIVALI-Universidade do Vale do Itajai, R. Uruguai, 458, 88302-202, Itajai, Santa Catarina (Brazil); Laboratory of Biopolymers, UFPR-Universidade Federal do Parana, CxP 19081, 81531-990, Curitiba, Parana (Brazil); Vitorino, J.C. [Group of Industrial Microbiology, UNIVALI-Universidade do Vale do Itajai, R. Uruguai, 458, 88302-202, Itajai, Santa Catarina (Brazil); Sierakowski, Maria-R. [Laboratory of Biopolymers, UFPR-Universidade Federal do Parana, CxP 19081, 81531-990, Curitiba, Parana (Brazil); Tischer, C.A. [Group of Industrial Microbiology, UNIVALI-Universidade do Vale do Itajai, R. Uruguai, 458, 88302-202, Itajai, Santa Catarina (Brazil)], E-mail: cesarat@uol.com.br

    2009-03-01

    Bacterial cellulose (BC), biosynthesized by Acetobacter xylinum, was produced in a medium consisting of rice bark pre-treated with an enzymatic pool. Rice bark was evaluated as a carbon source by complete enzymatic hydrolysis and monosaccharide composition (GC-MS of derived alditol acetates). It was treated enzymatically and then enriched with glucose up to 4% (w/v). The BC produced by static and aerated processes was purified by immersion in 0.1 M NaOH, was characterized by FT-IR, X-ray diffraction and the biosynthetic nanostructures were evaluated by Scanning Electronic (SEM), Transmission Electronic (TEM) and Atomic Force Microscopy (AFM). The BC films arising from static fermentation with rice bark/glucose and glucose are tightly intertwined, partially crystalline, being type II cellulose produced with rice bark/glucose, and type I to the produced in a glucose medium. The nanostructurated biopolymer obtained from the rice bark/glucose medium, produced in a reactor with air flux had micro- and nanospheres linked to nanofibers of cellulose. These results indicate that the bark components, namely lignins, hemicelluloses or mineral contents, interact with the cellulose forming micro- and nanostructures with potential use to incorporate drugs.

  13. Magnesium improves hydrogen production by a novel fermentative hydrogen-producing bacterial strain B49

    Institute of Scientific and Technical Information of China (English)

    WANG Xiang-jing; REN Nan-qi; XIANG Wen-sheng

    2005-01-01

    Batch experiments were conducted to investigate the effects of magnesium on glucose metabolism, including growth and hydrogen-producing capacity of fermentative hydrogen-producing bacterial strain B49. These abilities were enhanced with an increase in magnesium concentration. At the end of fermentation from 10 g/L ratio of ethanol amount (mg/L) to acetate amount (mg/L) was 1.1, and the accumulated hydrogen volume hydrogen volume was increased to 2 360. 5 mL H2/L culture, the ratio of ethanol amount (mg/L) to acetate amount (mg/L) was increased to 1.3 and polysaccharide was decreased to 2. 5 mg/L. Moreover, the magnesium solution addition to the medium at different fermentation times affected hydrogen-producing ability. However,the later the addition time was postponed, the less the effect was on hydrogen evolution. Further experiments confirmed the enhancement was dependent on magnesium ions and not on the other inorganic ions such as SO42- or Cl-, which constituted the magnesium salts.

  14. Integral measurements of neutron production in spallation targets

    International Nuclear Information System (INIS)

    Measurements of neutron production for thick iron, tungsten and lead targets of different diameter prototypic for spallation systems have been made at SATURNE in an incident proton energy range from 400 MeV to 2 GeV. TIERCE code system calculations are in good agreement with experiment for iron and large diameter tungsten and lead targets. They overestimate the measured neutron production for tungsten and lead targets for diameter ≤20 cm. (author)

  15. Measurement of exclusive eta' production in γγ reactions

    International Nuclear Information System (INIS)

    We observe γγ->eta' production in the reaction e+e- -> e+e-π+π-γ. We measure the product GAMMAsub(γγ)(eta')B(eta' -> rho0γ) to be 1.14+-0.08+-0.11 keV. A first measurement of the γγ->eta' transition form factor is made for Q2 up to 1 GeV2. (orig.)

  16. Productivity measurement and growth in Nigeria: challenges and prospects

    Directory of Open Access Journals (Sweden)

    Chibueze C. IKEJI

    2010-12-01

    Full Text Available Productivity (growth measurements (describing the assessment of an economy’s rate of change in the ratio of a volume measure of output to a volume measure of input use and related analysis are regular undertakings by staff of economic development of most nations and development institutions such as the OECD. Although they strive to accomplish objectives related to studying efficiency or the achievement of maximum output physically achievable under the use of current technology and given inputs, accounting for the contribution of real costs savings; introduction of benchmarks for production processes and to highlight living standards obtaining at points in time, its emphasis has been at the expense of examination of issues related to society (institutions, history, innovation and productivity change, which are concerned with promoting growth beyond mere productivity accounting. This paper has attempted to address all these issues as they pertain to Nigeria’s rather stagnant or declining economy. This slight modification was prompted by changes from philosophers concerned with the wider area of productivity measurement and change. The literature agrees that productivity measurement (growth accounting only “identified the significance of different proximate sources of growth” but fails to employ institutional, historical case studies to investigate the underlying causes of the growth, innovation and productivity change. Details of deficiencies related to the foregoing issues are examined and policy recommendations drafted and presented to assist practitioners, policy and decision makers and other stakeholders.

  17. Allais Measure of Production Sector Waste Due to Quotas, An

    OpenAIRE

    Lilyan E. Fulginiti; Richard K. Perrin

    1996-01-01

    Agricultural production quotas are policy instruments that many countries have adopted as a means of transferring income from consumers to producers. Here the partial equilibrium approach of Allais and Diewert is adapted to measure the efficiency loss in the production sector due to quotas. Published in American Journal of Agricultural Economics 77(November 1995):865-74. 1995.

  18. Endogenous ethanol production in a patient with chronic intestinal pseudo-obstruction and small intestinal bacterial overgrowth.

    Science.gov (United States)

    Spinucci, Giulio; Guidetti, Mariacristina; Lanzoni, Elisabetta; Pironi, Loris

    2006-07-01

    The case of the gastrointestinal production of ethanol from Candida albicans and Saccharomyces cerevisiae in a Caucasian man with chronic intestinal pseudo-obstruction is reported. The patient, who declared to have always abstained from alcohol, was hospitalized for abdominal pain, belching and mental confusion. The laboratory findings showed the presence of ethanol in the blood. Gastric juice and faecal microbiological cultures were positive for C. albicans and S. cerevisiae. At home, he was on oral antibiotic therapy with amoxicillin plus clavulanic acid for a small bowel bacterial overgrowth, associated with a simple sugar-rich diet. Twenty-four hours after stopping both the antibiotic therapy and the simple sugar-rich diet, the blood ethanol disappeared. A provocative test, performed by giving amoxicillin plus clavulanic acid associated with the simple sugar-rich diet was followed by the reappearance of ethanol in the blood. A review of the literature is reported.

  19. Production of Cold-Active Bacterial Lipases through Semisolid State Fermentation Using Oil Cakes

    OpenAIRE

    Babu Joseph; Supriya Upadhyaya; Pramod Ramteke

    2011-01-01

    Production of cold active lipase by semisolid state fermentation involves the use of agroindustrial residues. In the present study, semisolid state fermentation was carried out for the production of cold active lipase using Micrococcus roseus, isolated from soil samples of Gangotri glaciers, Western Himalayas. Among various substrate tested, groundnut oil cake (GOC) favored maximal yield of lipases at 15 ± 1°C within 48 h. Supplementation of glucose 1% (w/v) as additional carbon source and am...

  20. Bacterial ecology of PDO Coppa and Pancetta Piacentina at the end of ripening and after MAP storage of sliced product.

    Science.gov (United States)

    Busconi, Matteo; Zacconi, Carla; Scolari, Gianluigi

    2014-02-17

    The objective of this study was to evaluate the microbiota of two typical Italian PDO delicatessens Coppa and Pancetta Piacentina, produced in Piacenza area (Italy). Classical and molecular approaches were employed, in order to acquire knowledge on their bacterial ecology and its evolution after slicing and MAP storing; thus, the biodiversity of characteristic bacterial community, already present or introduced during such procedures, was studied in both full ripened and sliced samples from two producers (A and B) of the PDO district, packaged under MAP and stored at 2 and 8 °C for 30 days. The microbiota of the two kinds of Italian delicatessen demonstrated peculiar differences, particularly regarding the staphylococci and lactic acid bacteria (LAB) ratio. Moreover, some species within these two groups appeared to be linked to the kind of product: Leuconostoc, Lactobacillus versmoldensis and Staphylococcus saprophyticus were found only in Pancetta while Lactobacillus pentosus, Staphylococcus equorum, Staphylococcus xylosus, Staphylococcus sciuri and Macrococcus caseolyticus occurred only in Coppa. Also, both delicatessens from producer A were richer in LAB compared to those of producer B and the opposite applied for staphylococci. Interestingly, Tetragenococcus halophilus was detectable in all the samples and its presence in the sausage environment has been reported only for Capocollo. Storage did not substantially modify the microbiota composition, the only changes being the relative abundance of same sequences; S. xylosus was prevalent before slicing process and S. equorum at the end of MAP storage at both 2 °C and 8 °C. Concerning microbial contamination during the slicing process, our results suggest that the adopted procedures assure high hygienic quality standard of these typical products, with exception of a contamination by Psychrobacter psychrophilus in Coppa B. The possible origin of species rarely or never reported in the sausage environment and

  1. Exposure to bacterial signals does not alter pea aphids' survival upon a second challenge or investment in production of winged offspring.

    Directory of Open Access Journals (Sweden)

    Bas ter Braak

    Full Text Available Pea aphids have an obligate nutritional symbiosis with the bacteria Buchneraaphidicola and frequently also harbor one or more facultative symbionts. Aphids are also susceptible to bacterial pathogen infections, and it has been suggested that aphids have a limited immune response towards such pathogen infections compared to other, more well-studied insects. However, aphids do possess at least some of the genes known to be involved in bacterial immune responses in other insects, and immune-competent hemocytes. One possibility is that immune priming with microbial elicitors could stimulate immune protection against subsequent bacterial infections, as has been observed in several other insect systems. To address this hypothesis we challenged aphids with bacterial immune elicitors twenty-four hours prior to live bacterial pathogen infections and then compared their survival rates to aphids that were not pre-exposed to bacterial signals. Using two aphid genotypes, we found no evidence for immune protection conferred by immune priming during infections with either Serratia marcescens or with Escherichia coli. Immune priming was not altered by the presence of facultative, beneficial symbionts in the aphids. In the absence of inducible immune protection, aphids may allocate energy towards other defense traits, including production of offspring with wings that could escape deteriorating conditions. To test this, we monitored the ratio of winged to unwinged offspring produced by adult mothers of a single clone that had been exposed to bacterial immune elicitors, to live E. coli infections or to no challenge. We found no correlation between immune challenge and winged offspring production, suggesting that this mechanism of defense, which functions upon exposure to fungal pathogens, is not central to aphid responses to bacterial infections.

  2. Valorization of lubricant-based wastewater for bacterial neutral lipids production: Growth-linked biosynthesis.

    Science.gov (United States)

    Da Silva, Pedro D M P; Lima, Filipa; Alves, Maria Madalena; Bijmans, Martijn F M; Pereira, Maria Alcina

    2016-09-15

    Lipids produced by microorganisms are currently of great interest as raw material for either biofuels or oleochemicals production. Significant biosynthesis of neutral lipids, such as triacylglycerol (TAG) and wax esters (WE) are thought to be limited to a few strains. Hydrocarbonoclastic bacteria (HCB), key players in bioremediation of hydrocarbon contaminated ecosystems, are among this group of strains. Hydrocarbon rich wastewaters have been overlooked concerning their potential as raw material for microbial lipids production. In this study, lubricant-based wastewater was fed, as sole carbon source, to two HCB representative wild strains: Alcanivorax borkumensis SK2, and Rhodococcus opacus PD630. Neutral lipid production was observed with both strains cultivated under uncontrolled conditions of pH and dissolved oxygen. A. borkumensis SK2 was further investigated in a pH- and OD-controlled fermenter. Different phases were assessed separately in terms of lipids production and alkanes removal. The maximum TAG production rate occurred during stationary phase (4 mg-TAG/L h). The maximum production rate of WE-like compounds was 15 mg/L h, and was observed during exponential growth phase. Hydrocarbons removal was 97% of the gas chromatography (GC) resolved straight-chain alkanes. The maximum removal rate was observed during exponential growth phase (6 mg-alkanes/L h). This investigation proposes a novel approach for the management of lubricant waste oil, aiming at its conversion into valuable lipids. The feasibility of the concept is demonstrated under low salt (0.3%) and saline (3.3%) conditions, and presents clues for its technological development, since growth associated oil production opens the possibility for establishing continuous fermentation processes. PMID:27244293

  3. Structural insights into inhibition of lipid I production in bacterial cell wall synthesis.

    Science.gov (United States)

    Chung, Ben C; Mashalidis, Ellene H; Tanino, Tetsuya; Kim, Mijung; Matsuda, Akira; Hong, Jiyong; Ichikawa, Satoshi; Lee, Seok-Yong

    2016-05-26

    Antibiotic-resistant bacterial infection is a serious threat to public health. Peptidoglycan biosynthesis is a well-established target for antibiotic development. MraY (phospho-MurNAc-pentapeptide translocase) catalyses the first and an essential membrane step of peptidoglycan biosynthesis. It is considered a very promising target for the development of new antibiotics, as many naturally occurring nucleoside inhibitors with antibacterial activity target this enzyme. However, antibiotics targeting MraY have not been developed for clinical use, mainly owing to a lack of structural insight into inhibition of this enzyme. Here we present the crystal structure of MraY from Aquifex aeolicus (MraYAA) in complex with its naturally occurring inhibitor, muraymycin D2 (MD2). We show that after binding MD2, MraYAA undergoes remarkably large conformational rearrangements near the active site, which lead to the formation of a nucleoside-binding pocket and a peptide-binding site. MD2 binds the nucleoside-binding pocket like a two-pronged plug inserting into a socket. Further interactions it makes in the adjacent peptide-binding site anchor MD2 to and enhance its affinity for MraYAA. Surprisingly, MD2 does not interact with three acidic residues or the Mg(2+) cofactor required for catalysis, suggesting that MD2 binds to MraYAA in a manner that overlaps with, but is distinct from, its natural substrate, UDP-MurNAc-pentapeptide. We have determined the principles of MD2 binding to MraYAA, including how it avoids the need for pyrophosphate and sugar moieties, which are essential features for substrate binding. The conformational plasticity of MraY could be the reason that it is the target of many structurally distinct inhibitors. These findings can inform the design of new inhibitors targeting MraY as well as its paralogues, WecA and TarO. PMID:27088606

  4. Cost-effective production of bacterial cellulose in static cultures using distillery wastewater.

    Science.gov (United States)

    Wu, Jyh-Ming; Liu, Ren-Han

    2013-03-01

    Thin stillage (TS), wastewater from rice wine distillery, was used as a cost-free feedstock to replace the costly traditional Hestrin and Schramm (HS) medium for BC production by Gluconacetobacter xylinus. Due to the rich organic acids and amino acids content in TS, BC production was significantly enhanced as 50 (v/v) % of HS medium was replaced with TS. In the 50/50 TS-HS medium, BC concentration of 6.26 g/l could be obtained after 7 days static cultivation which is approximately 50% higher than that could be produced in HS-only medium. The BC produced by TS containing medium had slightly denser reticulated structures and higher crystallinity index values but with lower water holding capacities than that obtained from HS medium. Based on the 50% cost-free TS, the 50/50 TS-HS medium had a BC production feedstock cost about 67% lower than that of traditional HS medium. The employment of cost-free TS to replace a portion of HS medium to achieve a higher BC production not only can reduce the BC production cost but also solve the wastewater disposal problem of winery industry.

  5. Measurement of W/Z production with the ATLAS detector

    CERN Document Server

    Sauvan, JB; The ATLAS collaboration

    2012-01-01

    The production of W and Z bosons at the LHC has been measured with the ATLAS detector. These measurements include inclusive and differential cross sections, $W$ polarisation, and the polarisation of tau leptons from W decays. They show sensitivity to the proton structure and are also used to test predictions from perturbative QCD and phenomenological models.

  6. Does Input Quality Drive Measured Differences in Firm Productivity?

    DEFF Research Database (Denmark)

    Fox, Jeremy T.; Smeets, Valerie Anne Rolande

    Firms in the same industry can differ in measured productivity by multiples of 3. Griliches (1957) suggests one explanation: the quality of inputs differs across firms. We add labor market history variables such as experience and firm and industry tenure, as well as general human capital measures...

  7. Measurements of strangeness production in the STAR experiment at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, W.K. [Wayne State Univ., Detroit, MI (United States)

    1995-07-15

    Simulations of the ability of the STAR (Solenoidal Tracker at RHIC) detector to measure strangeness production in central Au+Au collisions at RHIC are presented. Emphasis is placed on the reconstruction of short lived particles using a high resolution inner tracker. The prospects for performing neutral kaon interferometry are discussed. Simulation results for measurements of strange and multi-strange baryons are presented.

  8. Product formation from thiophene by a mixed bacterial culture. Influence of benzene as growth substrate

    DEFF Research Database (Denmark)

    Rivas, Isabelle Marie; Mosbæk, Hans; Arvin, Erik

    2003-01-01

    The influence of benzene as a growth substrate on the cometabolic conversion of thiophene was investigated in batch systems with microorganisms originating from an creosote contaminated site. Benzene was shown to stimulate the conversion of thiophene with a first-order rate, during the initial...... phase of transformation. The microorganisms were able to transform thiophene in the absence of benzene at a zero-order rate. Thiophene was converted to five oxidation products, regardless of the presence of benzene. Benzene had no influence on the distribution of these oxidation products. The main...

  9. Measurement of the ZZ production cross section with ATLAS

    Energy Technology Data Exchange (ETDEWEB)

    Ellinghaus, Frank; Schmitz, Simon; Tapprogge, Stefan [Institut fuer Physik, Johannes Gutenberg-Universitaet Mainz (Germany); Collaboration: ATLAS-Collaboration

    2015-07-01

    The study of the ZZ production has an excellent potential to test the electroweak sector of the Standard Model, where Z boson pairs can be produced via non-resonant processes or via Higgs decays. A deviation from the Standard Model expectation for the ZZ production cross section would be an indication for new physics. This could manifest itself in so called triple gauge couplings via ZZZ or ZZγ, which the Standard Model forbids at tree level. The measurement of the ZZ production cross section is based on an integrated luminosity of 20.3 fb{sup -1} of proton-proton collision data at √(s) = 8 TeV recorded with the ATLAS detector in 2012. Measurements of differential cross sections as well as searches for triple gauge couplings have been performed. This talk presents the measurement and analysis details of the ZZ production in the ZZ → 4l channel.

  10. Measurement and Comparison of Productivity Performance Under Fuzzy Imprecise Data

    Directory of Open Access Journals (Sweden)

    Avninder Gill

    2011-08-01

    Full Text Available The creation of goods and services requires changing the expended resources into the outputgoods and services. How efficiently we transform these input resources into goods and servicesdepends on the productivity of the transformation process. However, it has been observedthere is always a vagueness or imprecision associated with the values of inputs and outputs.Therefore, it becomes hard for a productivity measurement expert to specify the amount ofresources and the outputs as exact scalar numbers. The present paper, applies fuzzy settheory to measure and compare productivity performance of transformation processes whennumerical data cannot be specified in exact terms. The approach makes it possible to measureand compare productivity of organizational units (including non-government and non-profitentities when the expert inputs can not be specified as exact scalar quantities. The model hasbeen applied to compare productivity of different branches of a company.

  11. PROCESS AND PRODUCT QUALITY ASSURANCE MEASURES IN CMMI

    Directory of Open Access Journals (Sweden)

    Mahmoud Khraiwesh

    2014-10-01

    Full Text Available Process and product quality assurance are very important aspects in development of software. Process and product quality assurance monitor the software engineering processes and methods to ensure quality. It is the process of confirming and verifying that whether services and products meet the customer expectation or not. This research will identify general measures for the specific goals and its specific practices of Process and Product Quality Assurance Process Area in Capability Maturity Model Integration (CMMI. CMMI is developed by Software Engineering Institute (SEI in Carnegie Mellon University in USA. CMMI is a framework for assessment and improvement of computer information systems. The procedure we used to determine the measures is to apply the Goal Questions Metrics (GQM approach to the two specific goals and its four specific practices of Process and Product Quality Assurance Process Area in CMMI.

  12. Self-potential and Geochemical Measurements of Microbially Mediated Bacterial Sulfate Reduction in Saturated Sediments

    Science.gov (United States)

    Park, S.; Wolf, L. W.; Lee, M.; Saunders, J.

    2004-12-01

    In situ bioremediation is a non-invasive groundwater remediation technique that stimulates microorganisms to catalyze desirable redox reactions. Using a series of laboratory experiments, we explored the suitability of self-potential methods for monitoring bioremediation of metals contamination. Each experiment was designed to quantify the relationship between electrical potential and changing redox conditions and to determine factors influencing this relationship. In the first experiment, we introduced sulfate-reducting bacteria (SRB) into a Plexiglas tank containing autoclaved quartz sand saturated with an iron-rich Desulfovibrio (a sulfate-reducing bacteria) media. An array of non-polarizable electrodes positioned on the sediment surface was used to record electrical potentials both prior to and after inoculation for about 40 days. Changes in water chemistry were determined through a series of samples taken before, during and after the experiments. A significant decrease in total iron occurred after 3 days near the injection site; however, a clearly discernable decrease in electrical potential was not perceived until ~ day 10. Contoured SP data indicate that the redox front migrated away from the injection site over time. This change probably reflects the changing water chemistry as well as bacterial migration, as iron close to the injection site was consumed. The second experiment consisted of 4 glass columns, two of which were inoculated with SRB. The first pair contained sediment similar to the tank experiment saturated with an iron-rich media. The second pair contained the same sediment but was saturated with acid-mine drainage (AMD) collected from a contaminated field site. Each column was identically instrumented with a system of four electrodes. In the active columns, an increase in pH, a decrease in sulfate and a significant decrease in total iron in the media column accompany a decrease in electrical potential after about 10 days. Results of the study

  13. Dimensional measurements with submicrometer uncertainty in production environment

    DEFF Research Database (Denmark)

    De Chiffre, L.; Gudnason, M. M.; Madruga, D.

    2015-01-01

    The work concerns a laboratory investigation of a method to achieve dimensional measurements with submicrometer uncertainty under conditions that are typical of a production environment. The method involves the concurrent determination of dimensions and material properties from measurements carried...... gauge blocks along with their uncertainties were estimated directly from the measurements. The length of the two workpieces at the reference temperature of 20 °C was extrapolated from the measurements and compared to certificate values. The investigations have documented that the developed approach...... and laboratory equipment allow traceable length measurements with expanded uncertainties (k=2) below 1 μm....

  14. A secretory system for bacterial production of high-profile protein targets

    DEFF Research Database (Denmark)

    Kotzsch, Alexander; Vernet, Erik; Hammarström, Martin;

    2011-01-01

    Escherichia coli represents a robust, inexpensive expression host for the production of recombinant proteins. However, one major limitation is that certain protein classes do not express well in a biologically relevant form using standard expression approaches in the cytoplasm of E. coli. To impr...

  15. Measurement of beauty production from dimuon events at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Chekanov, S.; Derrick, M.; Magill, S. [Argonne National Laboratory, Argonne, IL (United States)] (and others)

    2008-09-15

    Beauty production in events containing two muons in the final state has been measured with the ZEUS detector at HERA using an integrated luminosity of 114 pb{sup -1}. A low transverse-momentum threshold for muon identification, in combination with the large rapidity coverage of the ZEUS muon system, gives access to almost the full phase space for beauty production. The total cross section for beauty production in ep collisions at {radical}(s) = 318 GeV has been measured to be {sigma}{sub tot}(ep {yields} b anti bX) = 13.9 {+-} 1.5(stat.){sub -4.3}{sup +4.0}(syst.) nb. Differential cross sections and a measurement of b anti b correlations are also obtained, and compared to other beauty cross-section measurements, Monte Carlo models and next-to-leading-order QCD predictions. (orig.)

  16. Measurements of inclusive vector boson production from ATLAS

    Directory of Open Access Journals (Sweden)

    Karnevskiy Mikhail

    2015-01-01

    Full Text Available The measurements of single W, Z boson production in association with jets probes QCD in a multi-scale environment. In this paper, we summarize the latest measurements of W+jet and Z+jet production and their ratio, extending to high jet multiplicities over a large set of kinematic distributions for proton-proton collisions at a center of mass energy of 7 TeV data at the LHC. The results are compared to the latest theoretical predictions of modern Monte Carlo generators. In addition, the measurement of production of vector bosons in association with heavy flavours allows to study c and b-quark parton distribution functions (PDFs and gluon splitting effects. Also the corresponding measurements of W + c and Z + b(b are reported and compared to predictions based on various PDFs in four and five-flavour schemes.

  17. A duplex PCR-based assay for measuring the amount of bacterial contamination in a nucleic acid extract from a culture of free-living protists.

    Directory of Open Access Journals (Sweden)

    Alan O Marron

    Full Text Available BACKGROUND: Cultures of heterotrophic protists often require co-culturing with bacteria to act as a source of nutrition. Such cultures will contain varying levels of intrinsic bacterial contamination that can interfere with molecular research and cause problems with the collection of sufficient material for sequencing. Measuring the levels of bacterial contamination for the purposes of molecular biology research is non-trivial, and can be complicated by the presence of a diverse bacterial flora, or by differences in the relative nucleic acid yield per bacterial or eukaryotic cell. PRINCIPAL FINDINGS: Here we describe a duplex PCR-based assay that can be used to measure the levels of contamination from marine bacteria in a culture of loricate choanoflagellates. By comparison to a standard culture of known target sequence content, the assay can be used to quantify the relative proportions of bacterial and choanoflagellate material in DNA or RNA samples extracted from a culture. We apply the assay to compare methods of purifying choanoflagellate cultures prior to DNA extraction, to determine their effectiveness in reducing bacterial contamination. Together with measurements of the total nucleic acid concentration, the assay can then be used as the basis for determining the absolute amounts of choanoflagellate DNA or RNA present in a sample. CONCLUSIONS: The assay protocol we describe here is a simple and relatively inexpensive method of measuring contamination levels in nucleic acid samples. This provides a new way to establish quantification and purification protocols for molecular biology and genomics in novel heterotrophic protist species. Guidelines are provided to develop a similar protocol for use with any protistan culture. This assay method is recommended where qPCR equipment is unavailable, where qPCR is not viable because of the nature of the bacterial contamination or starting material, or where prior sequence information is insufficient

  18. Optimization of biohydrogen yield produced by bacterial consortia using residual glycerin from biodiesel production.

    Science.gov (United States)

    Faber, Mariana de Oliveira; Ferreira-Leitão, Viridiana Santana

    2016-11-01

    The aims of this study were to simplify the fermentation medium and to optimize the conditions of dark fermentation of residual glycerin to produce biohydrogen. It was possible to remove all micronutrients of fermentation medium and improve biohydrogen production by applying residual glycerin as feedstock. After statistical analysis of the following parameters pH, glycerin concentration and volatile suspended solids, the values of 5.5; 0.5g.L(-1) and 8.7g.L(-1), respectively, were defined as optimum condition for this process. It generated 2.44molH2/molglycerin, an expressive result when compared to previous results reported in literature and considering that theoretical yield of H2 from glycerol in dark fermentation process is 3molH2/molglycerol. This study allowed the improvement of yield and productivity by 68% and 67%, respectively. PMID:27501033

  19. Optimization of biohydrogen yield produced by bacterial consortia using residual glycerin from biodiesel production.

    Science.gov (United States)

    Faber, Mariana de Oliveira; Ferreira-Leitão, Viridiana Santana

    2016-11-01

    The aims of this study were to simplify the fermentation medium and to optimize the conditions of dark fermentation of residual glycerin to produce biohydrogen. It was possible to remove all micronutrients of fermentation medium and improve biohydrogen production by applying residual glycerin as feedstock. After statistical analysis of the following parameters pH, glycerin concentration and volatile suspended solids, the values of 5.5; 0.5g.L(-1) and 8.7g.L(-1), respectively, were defined as optimum condition for this process. It generated 2.44molH2/molglycerin, an expressive result when compared to previous results reported in literature and considering that theoretical yield of H2 from glycerol in dark fermentation process is 3molH2/molglycerol. This study allowed the improvement of yield and productivity by 68% and 67%, respectively.

  20. Mucosal Immune Regulation in Intestinal Disease. The role of bacterial products, food components and drugs

    OpenAIRE

    Bol-Schoenmakers, M

    2009-01-01

    The challenge of the mucosal gut associated immune system is to remain unresponsive to food products and commensal microbiota, while mounting an appropriate immune response towards pathogens. This implicates the necessity of tight immune regulation within the gut associated lymphoid tissue (GALT). Imbalance between tolerance and immunity (e.g. intestinal homeostasis) contributes to the pathogenesis of intestinal diseases like inflammatory bowel disease (IBD) and food allergies. The first part...

  1. A secretory system for bacterial production of high-profile protein targets

    OpenAIRE

    Kotzsch, Alexander; Vernet, Erik; Hammarström, Martin; Berthelsen, Jens; Weigelt, Johan; Gräslund, Susanne; Sundström, Michael

    2011-01-01

    Escherichia coli represents a robust, inexpensive expression host for the production of recombinant proteins. However, one major limitation is that certain protein classes do not express well in a biologically relevant form using standard expression approaches in the cytoplasm of E. coli. To improve the usefulness of the E. coli expression platform we have investigated combinations of promoters and selected N-terminal fusion tags for the extracellular expression of human target proteins. A co...

  2. Identification of the Bacterial Microflora in Dairy Products by Temporal Temperature Gradient Gel Electrophoresis

    OpenAIRE

    Ogier, Jean-Claude; Son, Olivier; Gruss, Alexandra; Tailliez, Patrick; Delacroix-Buchet, Agnes

    2002-01-01

    Numerous microorganisms, including bacteria, yeasts, and molds, are present in cheeses, forming a complex ecosystem. Among these organisms, bacteria are responsible for most of the physicochemical and aromatic transformations that are intrinsic to the cheesemaking process. Identification of the bacteria that constitute the cheese ecosystem is essential for understanding their individual contributions to cheese production. We used temporal temperature gradient gel electrophoresis (TTGE) to ide...

  3. Biopolymer Production by Bacterial Enrichment Cultures Using Non-Fermented Substrates

    OpenAIRE

    Moralejo Gárate, H.

    2014-01-01

    Polyhydroxyalkanotes (PHAs) are naturally occurring polymers synthesized by a wide range of microorganisms. Their physiological role is to act as carbon and energy reserves, and their mechanical and physical properties are similar to those of petrochemical plastics. PHAs can be synthesized from renewable materials and they are biodegradable. Considering these properties, PHAs are commonly known as bioplastics. Commercial processes for the production of PHA are based on the use of pure culture...

  4. Recombinant production of bacterial toxins and their derivatives in the methylotrophic yeast Pichia pastoris

    OpenAIRE

    Gurkan Cemal; Ellar David J

    2005-01-01

    Abstract The methylotrophic yeast Pichia pastoris is a popular heterologous expression host for the recombinant production of a variety of prokaryotic and eukaryotic proteins. The rapid emergence of P. pastoris as a robust heterologous expression host was facilitated by the ease with which it can be manipulated and propagated, which is comparable to that of Escherichia coli and Saccharomyces cerevisiae. P. pastoris offers further advantages such as the tightly-regulated alcohol oxidase promot...

  5. Anti-Biofilm Performance of Three Natural Products against Initial Bacterial Attachment

    OpenAIRE

    Stokes, Keith R.; Dennington, Simon P.; Paul Stoodley; Maria Salta; Wharton, Julian A.

    2013-01-01

    Marine bacteria contribute significantly towards the fouling consortium, both directly (modern foul release coatings fail to prevent “slime” attachment) and indirectly (biofilms often excrete chemical cues that attract macrofouling settlement). This study assessed the natural product anti-biofilm performance of an extract of the seaweed, Chondrus crispus, and two isolated compounds from terrestrial sources, (+)-usnic acid and juglone, against two marine biofilm forming bacteria, Cobetia marin...

  6. Bacterial production and transformation of dissolved neutral sugars and amino acids in seawater

    OpenAIRE

    L. Jørgensen; Lechtenfeld, O.; Benner, R.; Middelboe, M.; Stedmon, C.A.

    2014-01-01

    Dissolved organic matter (DOM) in the ocean consists of a heterogeneous mixture of molecules, most of which are of unknown origin. Neutral sugars and amino acids are among the few recognizable biomolecules in DOM, and the molecular composition of these biomolecules is shaped primarily by biological production and degradation processes. This study provides insight into the bioavailability of biomolecules as well as the chemical composition of DOM produced by ...

  7. Strategies for production of active eukaryotic proteins in bacterial expression system

    Institute of Scientific and Technical Information of China (English)

    Orawan Khow; Sunutcha Suntrarachun

    2012-01-01

    Bacteria have long been the favorite expression system for recombinant protein production. However, the flaw of the system is that insoluble and inactive proteins are co-produced due to codon bias, protein folding, phosphorylation, glycosylation, mRNA stability and promoter strength. Factors are cited and the methods to convert to soluble and active proteins are described, for example a tight control of Escherichia coli milieu, refolding from inclusion body and through fusion technology.

  8. Food safety in raw milk production: risk factors associated to bacterial DNA contamination.

    Science.gov (United States)

    Cerva, Cristine; Bremm, Carolina; Reis, Emily Marques dos; Bezerra, André Vinícius Andrade; Loiko, Márcia Regina; Cruz, Cláudio Estêvão Farias da; Cenci, Alexander; Mayer, Fabiana Quoos

    2014-06-01

    While human illness from milkborne pathogens may be linked to contamination of the product after pasteurization or improper pasteurization, such diseases are usually associated with consumption of raw milk or its by-products. Molecular biology tools were applied to investigate contamination by Listeria monocytogenes, Salmonella spp., some pathogenic strains of Escherichia coli, and Campylobacter jejuni in 548 raw milk samples from 125 dairy farms established in two regions from southern Brazil. Moreover, 15 variables were evaluated for their association with raw milk contamination levels, and the risk factors were determined by multiple regression analysis. Salmonella spp. were more frequently detected, followed by pathogenic E. coli. There was difference in contamination index between the regions, in which risk factors such as temporary cattle confinement, low milk production, low milking machine cleaning frequency, and milk storage area without tile walls were identified. The risk factors were specific to each region studied. Nevertheless, the data can be used to improve milk quality of dairy farms/herds with similar management practices. PMID:24715203

  9. Marine Fungal and Bacterial Isolates for Lipase Production: A Comparative Study.

    Science.gov (United States)

    Patnala, H S; Kabilan, U; Gopalakrishnan, L; Rao, R M D; Kumar, D S

    2016-01-01

    Lipases, belonging to the class of enzymes called hydrolases, can catalyze triglycerides to fatty acids and glycerol. They are produced by microbes of plant and animal origin, and also by marine organisms. As marine microorganisms thrive in extreme conditions, lipases isolated from their origin possess characteristics of extremozymes, retain its activity in extreme conditions and can catalyze few chemical reactions which are impossible otherwise relative to the lipase produced from terrestrial microorganisms. Lipases are useful in many industries like detergent, food, leather, pharmaceutical, diary, etc. Few commercial enzymes have been developed and the use of them in certain industries like dairy, soaps are proved to be beneficial. There are few research papers reporting the production of lipase from marine bacteria and fungi. Lipase production involves two types of fermentation processes-solid-state fermentation (SSF) and submerged fermentation (SmF). Although SmF process is used conventionally, SSF process produces lipase in higher amounts. The production is also influenced by the composition of the medium, physiochemical parameters like temperature, pH, carbon, and nitrogen sources. PMID:27452166

  10. Hospitals Productivity Measurement Using Data Envelopment Analysis Technique.

    Directory of Open Access Journals (Sweden)

    Amin Torabipour

    2014-11-01

    Full Text Available This study aimed to measure the hospital productivity using data envelopment analysis (DEA technique and Malmquist indices.This is a cross sectional study in which the panel data were used in a 4 year period from 2007 to 2010. The research was implemented in 12 teaching and non-teaching hospitals of Ahvaz County. Data envelopment analysis technique and the Malmquist indices with an input-orientation approach, was used to analyze the data and estimation of productivity. Data were analyzed using the SPSS.18 and DEAP.2 software.Six hospitals (50% had a value lower than 1, which represents an increase in total productivity and other hospitals were non-productive. the average of total productivity factor (TPF was 1.024 for all hospitals, which represents a decrease in efficiency by 2.4% from 2007 to 2010. The average technical, technologic, scale and managerial efficiency change was 0.989, 1.008, 1.028, and 0.996 respectively. There was not a significant difference in mean productivity changes among teaching and non-teaching hospitals (P>0.05 (except in 2009 years.Productivity rate of hospitals had an increasing trend generally. However, the total average of productivity was decreased in hospitals. Besides, between the several components of total productivity, variation of technological efficiency had the highest impact on reduce of total average of productivity.

  11. Production of Bacterial Cellulose by Kombucha%红茶菌制备细菌纤维素的研究

    Institute of Scientific and Technical Information of China (English)

    唐水佳; 杨雪霞; 洪枫

    2012-01-01

    To find an efficient manufacturing strain and fermentation technology as well as a cost-effective medium are important strategies to solve the bottleneck problems that the industrialization of bacterial cellulose (BC) is facing, such as high production cost and low productivity. This paper investigated the effects of various carbon and nitrogen sources as well as concentration of tea water on the BC production by Kombucha (black tea fimgus) and Gluconacetobacter xylinus. The results showed that no big difference was found in the BC produced by the two types of microorganism. Kombucha had higher productivity of BC than Gluconacetobacter xylinus. The yield from Kombucha fermentation could be 3 times higher or more than G. xylinus.%寻找高效的生产菌和发酵工艺以及廉价高效的培养基是解决当前细菌纤维素产业化面临的高生产成本和低产率等瓶颈问题的重要手段。以红茶菌和木葡糖酸醋杆菌作为生产菌株,比较研究了不同碳源、氮源以及茶叶浓度对两种菌合成细菌纤维素的影响。结果表明,以红茶菌制备的细菌纤维素与木葡糖酸醋杆菌无本质区别;红茶菌生产细菌纤维素的效率显著高于木葡糖酸醋杆菌,产量可提高3倍以上。

  12. Production of bacterial cellulose by Gluconacetobacter hansenii CGMCC 3917 using only waste beer yeast as nutrient source.

    Science.gov (United States)

    Lin, Dehui; Lopez-Sanchez, Patricia; Li, Rui; Li, Zhixi

    2014-01-01

    In order to improve the use of waste beer yeast (WBY) for bacterial cellulose production by Gluconacetobacter hansenii CGMCC 3917, a two-step pre-treatment was designed. First WBY was treated by 4 methods: 0.1M NaOH treatment, high speed homogenizer, ultrasonication and microwave treatment followed by hydrolysis (121°C, 20 min) under mild acid condition (pH 2). The optimal pre-treatment conditions were evaluated by the reducing sugar yield after hydrolysis. 15% WBY treated by ultrasonication for 40 min had the highest reducing sugar yield (29.19%), followed by NaOH treatment (28.98%), high speed homogenizer (13.33%) and microwaves (13.01%). Treated WBY hydrolysates were directly supplied as only nutrient source for BC production. A sugar concentration of 3% WBY hydrolysates treated by ultrasonication gave the highest BC yield (7.02 g/L), almost 6 times as that from untreated WBY (1.21 g/L). Furthermore, the properties of the BC were as good as those obtained from the conventional chemical media.

  13. The utilization of sugar cane molasses with/without the presence of lignosulfonate for the production of bacterial cellulose.

    Science.gov (United States)

    Keshk, Sherif; Sameshima, Kazuhiko

    2006-09-01

    Production of bacterial cellulose (BC) using sugar cane molasses (MO) with/without the presence of lignosulfonate (MOL) as a sole carbon source in a Hestrin-Schramm medium (HS) was investigated. Six strains of Acetobacter xylinum [American Type Culture Collection 10245 and Institute of Fermentation in Osaka (IFO) 13693, 13772, 13773, 14815, and 15237] were screened for their BC production. The yield of the BC among all the strains from both the MO and MOL media was much higher than that from the HS medium. Acetobacter xylinum IFO 13772 was the best BC producer for all media. Furthermore, physical properties of these BC from the HS, MO, and MOL media were studied using Fourier-transform infrared spectroscopy, X-ray diffractometer, and cross polarization/magic angle spinning 13C nuclear magnetic resonance. There are no significant differences in the crystallinity and the recorded Ialpha fraction among the BC produced from the different media. A remarkable difference was only recorded in terms of viscosity. These results indicate that MO is a better carbon source than glucose for most of the strains investigated. PMID:16450110

  14. Production of nano bacterial cellulose from beverage industrial waste of citrus peel and pomace using Komagataeibacter xylinus.

    Science.gov (United States)

    Fan, Xin; Gao, Yue; He, Wanying; Hu, Hao; Tian, Ming; Wang, Kexing; Pan, Siyi

    2016-10-20

    Bacterial cellulose (BC) is a high-purity and robust cellulose that is utilised in medicine, consumer goods, and industrial practices. The present study aimed to investigate the suitability of beverage industrial waste for the production of BC by Komagataeibacter xylinus CICC No. 10529 and to study the structural properties of BC films in both citrus peel and pomace enzymolysis (CPPE) and Hestrin-Schramm (HS, Hestrin & Schramm, 1954) media. Under similar experimental conditions, the yield of BC from CPPE medium was 5.7±0.7g/L, which was higher than from HS medium (3.9±0.6g/L). To evaluate the structure of BC, fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and colour evaluation using a chroma meter were utilised. The average diameters of BC, obtained from CPPE and HS mediums, were 50nm and 60nm, respectively. The crystallinity index of BC from the CPPE medium was approximately 63%, which was lower than BC produced from the HS medium (65%). The two varieties of BC showed no significant differences in relation to their colour parameters. Therefore, BC production from CPPE medium had similar properties to BC from HS medium, but it is more environmentally friendly and cheaper to produce. PMID:27474656

  15. Measurement of the copy number of the master quorum-sensing regulator of a bacterial cell.

    Science.gov (United States)

    Teng, Shu-Wen; Wang, Yufang; Tu, Kimberly C; Long, Tao; Mehta, Pankaj; Wingreen, Ned S; Bassler, Bonnie L; Ong, N P

    2010-05-19

    Quorum-sensing is the mechanism by which bacteria communicate and synchronize group behaviors. Quantitative information on parameters such as the copy number of particular quorum-sensing proteins should contribute strongly to understanding how the quorum-sensing network functions. Here, we show that the copy number of the master regulator protein LuxR in Vibrio harveyi can be determined in vivo by exploiting small-number fluctuations of the protein distribution when cells undergo division. When a cell divides, both its volume and LuxR protein copy number, N, are partitioned with slight asymmetries. We measured the distribution functions describing the partitioning of the protein fluorescence and the cell volume. The fluorescence distribution is found to narrow systematically as the LuxR population increases, whereas the volume partitioning is unchanged. Analyzing these changes statistically, we determined that N = 80-135 dimers at low cell density and 575 dimers at high cell density. In addition, we measured the static distribution of LuxR over a large (3000) clonal population. Combining the static and time-lapse experiments, we determine the magnitude of the Fano factor of the distribution. This technique has broad applicability as a general in vivo technique for measuring protein copy number and burst size. PMID:20441767

  16. Commercialization of bacterial cell factories for the sustainable production of polyhydroxyalkanoate thermoplastics: progress and prospects.

    Science.gov (United States)

    Kumar, Abhishek; Srivastava, Janmejai K; Mallick, Nirupama; Singh, Akhilesh K

    2015-01-01

    Ubiquitous conventional plastics, generally manufactured from finite, nonsustainable fossil fuels are non-biodegradable wonder entities but their ill effect on Mother Nature has subsequently raised major environmental concerns like their safe disposal, solid waste management and several potential hazards. Such concerns have fuelled initiatives for research globally towards development of sustainable and eco-friendly bioplastics. The new generation of plastics called 'bioplastics' are polymers of long chain of repeating monomer units that are classified as photodegradable, semi-biodegradable, chemically synthesized and polyhydroxyalkanoates (PHAs). The commonly emerged novel bioplastics are polyesters of hydroxyalkanoates (HAs) called PHAs, which are lipoidic storage materials found in the cytosol of vast and diverse forms of bacteria. Among 150 different PHAs known so far, poly- 3-hydroxybutyrate is the most common and comprehensively characterized PHA. Interestingly, PHAs are only completely biodegradable plastics with material properties comparable to conventional plastics that can be achieved by regulating the co-monomers incorporation into PHAs backbone. PHA bioplastics are exploited in the form of user-friendly goods viz. films, absorbable sutures, bone plates, drug carriers, etc. Besides advantages, such useful entity(s) has major shortcomings as well like high production cost compared to conventional plastics. Precisely, in PHAs production, about fifty percent of the overall price is due to the carbon substrates. Consequently, exploring novel cost-effective substrates is a major compulsion for successful commercialization of this bioplastic, which is anticipated to reduce the cost of production as a result of advancing and intensifying research work. This review presents an insight and patent developments in the field of PHAs bioplastics. PMID:26073514

  17. A Clostridium difficile Cell Wall Glycopolymer Locus Influences Bacterial Shape, Polysaccharide Production and Virulence

    Science.gov (United States)

    Bertolo, Lisa; Monteiro, Mario A.; Agellon, Al; Viswanathan, V. K.; Vedantam, Gayatri

    2016-01-01

    Clostridium difficile is a diarrheagenic pathogen associated with significant mortality and morbidity. While its glucosylating toxins are primary virulence determinants, there is increasing appreciation of important roles for non-toxin factors in C. difficile pathogenesis. Cell wall glycopolymers (CWGs) influence the virulence of various pathogens. Five C. difficile CWGs, including PSII, have been structurally characterized, but their biosynthesis and significance in C. difficile infection is unknown. We explored the contribution of a conserved CWG locus to C. difficile cell-surface integrity and virulence. Attempts at disrupting multiple genes in the locus, including one encoding a predicted CWG exporter mviN, were unsuccessful, suggesting essentiality of the respective gene products. However, antisense RNA-mediated mviN downregulation resulted in slight morphology defects, retarded growth, and decreased surface PSII deposition. Two other genes, lcpA and lcpB, with putative roles in CWG anchoring, could be disrupted by insertional inactivation. lcpA- and lcpB- mutants had distinct phenotypes, implying non-redundant roles for the respective proteins. The lcpB- mutant was defective in surface PSII deposition and shedding, and exhibited a remodeled cell surface characterized by elongated and helical morphology, aberrantly-localized cell septae, and an altered surface-anchored protein profile. Both lcpA- and lcpB- strains also displayed heightened virulence in a hamster model of C. difficile disease. We propose that gene products of the C. difficile CWG locus are essential, that they direct the production/assembly of key antigenic surface polysaccharides, and thereby have complex roles in virulence. PMID:27741317

  18. Commercialization of bacterial cell factories for the sustainable production of polyhydroxyalkanoate thermoplastics: progress and prospects.

    Science.gov (United States)

    Kumar, Abhishek; Srivastava, Janmejai K; Mallick, Nirupama; Singh, Akhilesh K

    2015-01-01

    Ubiquitous conventional plastics, generally manufactured from finite, nonsustainable fossil fuels are non-biodegradable wonder entities but their ill effect on Mother Nature has subsequently raised major environmental concerns like their safe disposal, solid waste management and several potential hazards. Such concerns have fuelled initiatives for research globally towards development of sustainable and eco-friendly bioplastics. The new generation of plastics called 'bioplastics' are polymers of long chain of repeating monomer units that are classified as photodegradable, semi-biodegradable, chemically synthesized and polyhydroxyalkanoates (PHAs). The commonly emerged novel bioplastics are polyesters of hydroxyalkanoates (HAs) called PHAs, which are lipoidic storage materials found in the cytosol of vast and diverse forms of bacteria. Among 150 different PHAs known so far, poly- 3-hydroxybutyrate is the most common and comprehensively characterized PHA. Interestingly, PHAs are only completely biodegradable plastics with material properties comparable to conventional plastics that can be achieved by regulating the co-monomers incorporation into PHAs backbone. PHA bioplastics are exploited in the form of user-friendly goods viz. films, absorbable sutures, bone plates, drug carriers, etc. Besides advantages, such useful entity(s) has major shortcomings as well like high production cost compared to conventional plastics. Precisely, in PHAs production, about fifty percent of the overall price is due to the carbon substrates. Consequently, exploring novel cost-effective substrates is a major compulsion for successful commercialization of this bioplastic, which is anticipated to reduce the cost of production as a result of advancing and intensifying research work. This review presents an insight and patent developments in the field of PHAs bioplastics.

  19. Measuring productivity of customer knowledge management in projects

    Directory of Open Access Journals (Sweden)

    Tanika D. Sofianti

    2013-06-01

    Full Text Available Projects is one of the dominating modes of international business today. Companies interact with their customers in projects for a certain period. To explore the impact of customer knowledge management in such interactions, this paper promotes a measurement framework that can be used to measure the productivity of customer knowledge management. The measures are developed based on previous studies on customer knowledge management and project management. To verify the measures, this study conducted a survey involving 24 projects. The results of the study provide some insights into the impact of customer knowledge management in interactions between companies and their customers through projects.

  20. Characterization and crop production efficiency of diazotrophic bacterial isolates from coastal saline soils.

    Science.gov (United States)

    Barua, Shilajit; Tripathi, Sudipta; Chakraborty, Ashis; Ghosh, Sagarmoy; Chakrabarti, Kalyan

    2012-01-20

    Use of eco-friendly area specific salt tolerant bioinoculants is better alternatives to chemical fertilizer for sustainable agriculture in coastal saline soils. We isolated diverse groups of diazotrophic bacteria from coastal saline soils of different forest and agricultural lands in the Sundarbans, West Bengal, India, to study their effect on crop productivity in saline soils. Phenotypic, biochemical and molecular identifications of the isolates were performed. The isolates produced indole acetic acid, phosphatase, and solubilized insoluble phosphates. Sequence analysis of 16S rDNA identified the SUND_BDU1 strain as Agrobacterium and the strains SUND_LM2, Can4 and Can6 belonging to the genus Bacillus. The ARA activity, dinitrogen fixation and presence of nifH genes indicated they were diazotrophs. Field trials with these strains as bioinoculants were carried out during 2007-2009, with rice during August-December followed by Lady's finger during April-June. Microplots, amended with FYM inoculated with four bioinoculants individually were compared against sole FYM (5 t ha(-1)) and a sole chemical fertilizer (60:30:30 kg ha(-1) NPK) treated plot. The strain Can6 was by far the best performer in respect of yield attributes and productivity of studied crops. PMID:21596539

  1. Measurement of stau_1 pair production at CLIC

    CERN Document Server

    Muennich, A.

    2012-01-01

    We present a study performed for the CLIC Conceptual Design Report Volume 3 on the measurement of stau_1 pair production at sqrt(s) = 1.4 TeV. Only the hadronic decay of taus are considered. Results obtained using full detector simulation and including beam-induced backgrounds for the mass and for the production cross section of the stau_1 are discussed.

  2. Productivity Measurement in Manufacturing and the Expenditure Approach

    DEFF Research Database (Denmark)

    Schjerning, Bertel; Sørensen, Anders

    2008-01-01

    This paper studies conversion factors based on the expenditure approach and evaluates the appropriateness for international comparisons of output levels in manufacturing. We apply a consistency check based on the insight that relative productivity levels should be invariant to the choice of base...... conclusion is insensitive to the applied method for developing conversion factors. The implication is that we cannot measure relative productivity levels in manufacturing across countries using the expenditure approach....

  3. Patterns of hydrogen peroxide among lakes of the Mackenzie Delta and potential effects on bacterial production

    OpenAIRE

    Febria, Catherine Maria

    2005-01-01

    Lakes in the Mackenzie Delta have complex patterns of dissolved organic carbon (DOC) ranging from low levels of coloured DOC in lakes frequently flooded with riverwater to high levels of non-coloured DOC in infrequently flooded lakes. Hydrogen peroxide (H202) levels measured in 40 lakes at three times, ranging from summer solstice to late summer were highest around the solstice and in lakes of intermediate flood-frequency. Diurnal dynamics of H202, tracked for 40 hours during 24-hour sunlight...

  4. Proteomics as a quality control tool of pharmaceutical probiotic bacterial lysate products

    OpenAIRE

    Günter Klein; Schanstra, Joost P.; Janosch Hoffmann; Harald Mischak; Justyna Siwy; Kurt Zimmermann

    2013-01-01

    Probiotic bacteria have a wide range of applications in veterinary and human therapeutics. Inactivated probiotics are complex samples and quality control (QC) should measure as many molecular features as possible. Capillary electrophoresis coupled to mass spectrometry (CE/MS) has been used as a multidimensional and high throughput method for the identification and validation of biomarkers of disease in complex biological samples such as biofluids. In this study we evaluate the suitability of ...

  5. Engineering control of bacterial cellulose production using a genetic toolkit and a new cellulose-producing strain

    OpenAIRE

    Florea, Michael; Hagemann, Henrik; Santosa, Gabriella; Abbott, James; Micklem, Chris N.; Spencer-Milnes, Xenia; de Arroyo Garcia, Laura; Paschou, Despoina; Lazenbatt, Christopher; Kong, Deze; Chughtai, Haroon; Jensen, Kirsten; Freemont, Paul S.; Kitney, Richard; Reeve, Benjamin

    2016-01-01

    Bacterial cellulose is a remarkable material that is malleable, biocompatible, and over 10-times stronger than plant-based cellulose. It is currently used to create materials for tissue engineering, medicine, defense, electronics, acoustics, and fabrics. We describe here a bacterial strain that is readily amenable to genetic engineering and produces high quantities of bacterial cellulose in low-cost media. To reprogram this organism for biotechnology applications, we created a set of genetic ...

  6. Measurement of heat generation from simulated bituminized product

    International Nuclear Information System (INIS)

    The fire and explosion incident occurred at Bituminization Demonstration Facility of PNC Tokai Works on March 11, 1997. In order to ascertain the cause of incident, the investigation has been pushed forward. For the investigation, we prepared simulated bituminized product of measurement of heat generation in low temperature region less than 200degC. We used calvet Calorimeter MS80 for the heat generation measurement. Result of measurement, we were able to catch the feeble heat generation from bituminized product. The maximum calorific value that was able to detect it in isothermal measurement was approximately 1 mW/g in 160degC. It was approximately 2 mW/g in 200degC. And, as the another measurement, the measurement condition went heat rate by 0.01degC/minute, the highest temperature 190degC. As a result, the maximum generation of heat value that was able to detect it was approximately 0.5 mW/g. I changed simulated bituminized products and measured these. A difference of condition is salt particle size, salt content rate (45%, 60%), addition of the simulated precipitate. But there was not a difference in the generation of heat characteristic detected. (author)

  7. LHCb: Measurement of $D^{\\pm}$ Production Asymmetry at LHCb

    CERN Multimedia

    Xing, Zhou

    2012-01-01

    Heavy quark production in 7 TeV pp collisions at the LHC need not be flavour symmetric. Here the production asymmetry, $A_p$ , between $D_s^+$ and $D_s^-$ mesons is measured using the $\\phi\\pi$ decay mode. The difference between $\\pi^+$ and $\\pi^-$ detection efficiencies is measured using the ratio of fully reconstructed to partially reconstructed $D^*$ decays. Using 1 fb$^{-1}$ of data collected with the LHCb detector, we find $A_p = (-0.39 \\pm 0.22 \\pm 0.08)$%.

  8. Di-boson production measurements with the ATLAS detector

    CERN Document Server

    Chevalier, Laurent; The ATLAS collaboration

    2015-01-01

    Measurements diboson production cross sections in proton-proton interactions at 7 and 8 TeV are reported from the ATLAS experiment. The cross section results are measured in phase space regions defined by the decay kinematics and then extrapolated to the full phase spaces. Cross sections for WV (V=W or Z) production in the leptonic or semileptonic channels are compared to (N)NLO predictions of the Standard Model and are used to place constraints on anomalous triple-gauge-boson couplings. First LHC Run-2 results will be included if available.

  9. Direct measurement of cell wall stress-stiffening and turgor pressure in live bacterial cells

    CERN Document Server

    Deng, Yi; Shaevitz, Joshua W

    2011-01-01

    The mechanical properties of gram-negative bacteria are governed by a rigid peptidoglycan (PG) cell wall and the turgor pressure generated by the large concentration of solutes in the cytoplasm. The elasticity of the PG has been measured in bulk and in isolated sacculi and shown to be compliant compared to the overall stiffness of the cell itself. However, the stiffness of the cell wall in live cells has not been measured. In particular, the effects that pressure-induced stress might have on the stiffness of the mesh-like PG network have not been addressed even though polymeric materials often exhibit large amounts of stress-stiffening. We study bulging Escherichia coli cells using atomic force microscopy to separate the contributions of the cell wall and turgor pressure to the overall cell stiffness. We find strong evidence of power-law stress-stiffening in the E. coli cell wall, with an exponent of $1.07 \\pm 0.25$, such that the wall is significantly stiffer in live cells ($E\\sim32\\pm10$ MPa) than in unpres...

  10. Kinetic Monte Carlo Simulations and Molecular Conductance Measurements of the Bacterial Decaheme Cytochrome MtrF

    Energy Technology Data Exchange (ETDEWEB)

    Byun, H. S.; Pirbadian, S.; Nakano, Aiichiro; Shi, Liang; El-Naggar, Mohamed Y.

    2014-09-05

    Microorganisms overcome the considerable hurdle of respiring extracellular solid substrates by deploying large multiheme cytochrome complexes that form 20 nanometer conduits to traffic electrons through the periplasm and across the cellular outer membrane. Here we report the first kinetic Monte Carlo simulations and single-molecule scanning tunneling microscopy (STM) measurements of the Shewanella oneidensis MR-1 outer membrane decaheme cytochrome MtrF, which can perform the final electron transfer step from cells to minerals and microbial fuel cell anodes. We find that the calculated electron transport rate through MtrF is consistent with previously reported in vitro measurements of the Shewanella Mtr complex, as well as in vivo respiration rates on electrode surfaces assuming a reasonable (experimentally verified) coverage of cytochromes on the cell surface. The simulations also reveal a rich phase diagram in the overall electron occupation density of the hemes as a function of electron injection and ejection rates. Single molecule tunneling spectroscopy confirms MtrF's ability to mediate electron transport between an STM tip and an underlying Au(111) surface, but at rates higher than expected from previously calculated heme-heme electron transfer rates for solvated molecules.

  11. Summary of the COSY-11 Measurements of Hyperon Production

    CERN Document Server

    Grzonka, D

    2007-01-01

    The studies of hyperon production performed at COSY-11 are summarized. The results of the experiments in the reaction channels pp-->pK+Lambda, pp-->pK+Sigma0, and pp-->nK+Sigma+ are shown. Excitation functions fromthreshold up to about 90MeV excess energies have been evaluated with high precision for the Lambda and Sigma0 production. The Lambdap and Sigma0p final state interactions were extracted. The Sigma+ production was measured at 13 and 60 MeV excess energies.

  12. Isolation of non-sulphur photosynthetic bacterial strains efficient in hydrogen production at elevated temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Singh, S.P.; Srivastava, S.C. (Banaras Hindu Univ., Varanasi (IN). Centre of Advanced Study in Botany)

    1991-01-01

    Four strains of non-sulphur photosynthetic bacteria were isolated from root zone associations of aquatic plants like Azolla, Salvinia and Eichhornia, as well as the deep-water rice. Based on the gross cell morphology and pigmentation, the isolates resembled Rhodopseudomonas sp. and have been designated as BHU strains 1 to 4, respectively. When subjected to elevated temperature (from 33-45{sup o}C), substantial growth/hydrogen production could be observed only in strains 1 and 4. Strains 2 and 3 on the other hand, showed diminished growth and negligible hydrogen photoproduction. The BHU strains 1 and 4 have been selected as the most active (thermostable) hydrogen producing strains of local origin as far as the Indian tropical climate is concerned. (author).

  13. Biological role of pigment production for the bacterial phytopathogen Pantoea stewartii subsp. stewartii.

    Science.gov (United States)

    Mohammadi, Mojtaba; Burbank, Lindsey; Roper, M Caroline

    2012-10-01

    Pantoea stewartii subsp. stewartii, the causal agent of Stewart's wilt of sweet corn, produces a yellow carotenoid pigment. A nonpigmented mutant was selected from a bank of mutants generated by random transposon mutagenesis. The transposon insertion site was mapped to the crtB gene, encoding a putative phytoene synthase, an enzyme involved in the early steps of carotenoid biosynthesis. We demonstrate here that the carotenoid pigment imparts protection against UV radiation and also contributes to the complete antioxidant pathway of P. stewartii. Moreover, production of this pigment is regulated by the EsaI/EsaR quorum-sensing system and significantly contributes to the virulence of the pathogen in planta. PMID:22820327

  14. Comparison of some indigenous bacterial strains of pseudomonas ssp. for production of biosurfactants

    International Nuclear Information System (INIS)

    Some indigenous pseudomonas spp. were found to have the ability of emulsification, lowering the surface and interfacial tensions, and formation of high reciprocal CMCs. Six strains of Pseudomonas spp were compared for biosurfactant production grown on hexadecane. Supernatant from whole culture broth of these strains could lower surface tension from 65 mN/m to 28-32 nM/m, interfacial tension from 40 nM/m to 1-3 mN/m and had high reciprocal CMCs. When compared for emulsification ability by the culture broth of these strains, the emulsification index (E24) was found to range between 60-65. Biosurfactant containing culture broth of some strains could retain the property up to 80 C, pH of 13 and sodium chloride concentration for 17% which indicates their possible role in some depleted oil well. (author)

  15. Engineered bacterial polyester hydrolases efficiently degrade polyethylene terephthalate due to relieved product inhibition.

    Science.gov (United States)

    Wei, Ren; Oeser, Thorsten; Schmidt, Juliane; Meier, René; Barth, Markus; Then, Johannes; Zimmermann, Wolfgang

    2016-08-01

    Recent studies on the enzymatic degradation of synthetic polyesters have shown the potential of polyester hydrolases from thermophilic actinomycetes for modifying or degrading polyethylene terephthalate (PET). TfCut2 from Thermobifida fusca KW3 and LC-cutinase (LCC) isolated from a compost metagenome are remarkably active polyester hydrolases with high sequence and structural similarity. Both enzymes exhibit an exposed active site in a substrate binding groove located at the protein surface. By exchanging selected amino acid residues of TfCut2 involved in substrate binding with those present in LCC, enzyme variants with increased PET hydrolytic activity at 65°C were obtained. The highest activity in hydrolyzing PET films and fibers were detected with the single variant G62A and the double variant G62A/I213S. Both variants caused a weight loss of PET films of more than 42% after 50 h of hydrolysis, corresponding to a 2.7-fold increase compared to the wild type enzyme. Kinetic analysis based on the released PET hydrolysis products confirmed the superior hydrolytic activity of G62A with a fourfold higher hydrolysis rate constant and a 1.5-fold lower substrate binding constant than those of the wild type enzyme. Mono-(2-hydroxyethyl) terephthalate is a strong inhibitor of TfCut2. A determination of the Rosetta binding energy suggested a reduced interaction of G62A with 2PET, a dimer of the PET monomer ethylene terephthalate. Indeed, G62A revealed a 5.5-fold lower binding constant to the inhibitor than the wild type enzyme indicating that its increased PET hydrolysis activity is the result of a relieved product inhibition by mono-(2-hydroxyethyl) terephthalate. Biotechnol. Bioeng. 2016;113: 1658-1665. © 2016 Wiley Periodicals, Inc. PMID:26804057

  16. Method s for Measuring Productivity in Libraries and Information Centres

    Directory of Open Access Journals (Sweden)

    Mohammad Alaaei

    2009-04-01

    Full Text Available   Within Information centers, productivity is the result of optimal and effective use of information resources, service quality improvement, increased user satisfaction, pleasantness of working environment, increased motivation and enthusiasm of staff to work better. All contribute to the growth and development of information centers. Thus these centers would need to be familiar with methods employed in productivity measurement. Productivity is one of the criteria for evaluating system performance. In the past decades particular emphasis has been placed on measurement and improvement of human resource, creativity, innovation and expert analysis. Contemplation and efforts made towards identification of problems and issues and new means to make more useful and better resource management is the very definition of productivity. Simply put, productivity is the relationship between system output and the elements garnered to produce these outputs. The causality between variables and factors impacting on productivity is very complex. In information centers, given the large volume of elements involved, it seems necessary to increase efficiency and productivity

  17. Random walk of second class particles in product shock measures

    CERN Document Server

    Balazs, Marton; Kovacs, Peter; Rakos, Attila

    2009-01-01

    We consider shock measures in a class of conserving stochastic particle systems on Z. These shock measures have a product structure with a step-like density profile and include a second class particle at the shock position. We show for the asymmetric simple exclusion process, for the exponential bricklayers' process, and for a generalized zero range process, that under certain conditions these shocks, and therefore the second class particles, perform a simple random walk. Some previous results, including random walks of product shock measures and stationary shock measures seen from a second class particle, are direct consequences of our more general theorem. Multiple shocks can also be handled easily in this framework. Similar shock structure is also found in a nonconserving model, the branching coalescing random walk, where the role of the second class particle is played by the rightmost (or leftmost) particle.

  18. Charged fusion product loss measurements using nuclear activation

    International Nuclear Information System (INIS)

    In ITER, α particle loss measurements will be required in order to understand the alpha particle physics. Techniques capable of operating in a fusion reactor environment need further development. Recent experimental studies on JET demonstrated the potential of nuclear activation to measure the flux of escaping MeV ions. New results from MeV ion induced activation of metallic, ceramic, and crystal samples placed near the plasma edge are reported. Activation products were measured as function of orientation with respect to the magnetic field as well as function of the distance to the plasma. Sample activity was measured using ultralow-level gamma-ray spectrometry. Distribution of 14.68 MeV fusion proton induced activation products is strongly anisotropic in agreement with simulations and falls off sharply with increasing distance to the plasma. Prospects for using the technique in ITER are discussed.

  19. Proposal; Precise measurements of very forward particle production at RHIC

    CERN Document Server

    Itow, Y; Sako, T; Sakurai, N; Kasahara, K; Suzuki, T; Torii, S; Adriani, O; Bonechi, L; D'Alessandro, R; Mitsuka, G; Tricomi, A; Goto, Y; Tanida, K

    2014-01-01

    We propose a new experiment Relativistic Heavy Ion Collider forward (RHICf) for the precise measurements of very forward particle production at RHIC. The proposal is to install the LHCf Arm2 detector in the North side of the ZDC installation slot at the PHENIX interaction point. By installing high-resolution electromagnetic calorimeters at this location we can measure the spectra of photons, neutrons and pi0 at pseudorapidity eta>6.

  20. Catalytic irreversible inhibition of bacterial and plant arginine decarboxylase activities by novel substrate and product analogues.

    Science.gov (United States)

    Bitonti, A J; Casara, P J; McCann, P P; Bey, P

    1987-02-15

    Arginine decarboxylase (ADC) activity from Escherichia coli and two plant species (oats and barley) was inhibited by five new substrate (arginine) and product (agmatine) analogues. The five compounds, (E)-alpha-monofluoromethyldehydroarginine (delta-MFMA), alpha-monofluoromethylarginine (MFMA), alpha-monofluoromethylagatine (FMA), alpha-ethynylagmatine (EA) and alpha-allenylagmatine (AA), were all more potent inhibitors of ADC activity than was alpha-difluoromethylarginine (DFMA), the only irreversible inhibitor of this enzyme described previously. The inhibition caused by the five compounds was apparently enzyme-activated and irreversible, since the loss of enzyme activity followed pseudo-first-order kinetics, was time-dependent, the natural substrate of ADC (arginine) blocked the effects of the inhibitors, and the inhibition remained after chromatography of inhibited ADC on Sephadex G-25 or on overnight dialysis of the enzyme. DFMA, FMA, delta-MFMA and MFMA were effective at very low concentrations (10 nM-10 microM) at inhibiting ADC activity in growing E. coli. FMA was also shown to deplete putrescine effectively in E. coli, particularly when combined with an inhibitor of ornithine decarboxylase, alpha-monofluoromethyl-putrescine. The potential uses of the compounds for the study of the role of polyamine biosynthesis in bacteria and plants is discussed.

  1. Measurement of bacterial gene expression in vivo by laser capture microdissection and quantitative real-time RT-PCR

    DEFF Research Database (Denmark)

    Schou, Kirstine Klitgaard; Jensen, Tim Kåre; Angen, Øystein;

    2007-01-01

    Due to the relative small number of bacterial pathogens present in an infected host, exploration of pathogen gene expression in vivo is challenging. This study reports the development of a protocol for quantifying bacterial gene expression in vivo in Actinobacillus pleuropneumoniae using laser ca...... capture microdissection and real-time quantitative RT-PCR....

  2. Bacterial carbon cycling in a subarctic fjord

    DEFF Research Database (Denmark)

    Middelboe, Mathias; Glud, Ronnie Nøhr; Sejr, M.K.

    2012-01-01

    and BGE were positively correlated with BDOC concentration, suggesting that organic carbon availability was limiting bacterial activity and carbon conversion efficiency. Viral production was low (0.8–1.8 × 104 viruses mL−1 h−1) as compared to low-latitude environments, suggesting a relatively small effect......In this seasonal study, we examined the environmental controls and quantitative importance of bacterial carbon consumption in the water column and the sediment in the subarctic Kobbefjord, Greenland. Depth-integrated bacterial production in the photic zone varied from 5.0 ± 2.7 mg C m−2 d−1...... in February to 42 ± 28 mg C m−2 d−1 in May and 34 ± 7 mg C m−2 d−1 in September, corresponding to a bacterial production to primary production ratio of 0.34 ± 0.14, 0.07 ± 0.04, and 0.08 ± 0.06, respectively. Based on measured bacterial growth efficiencies (BGEs) of 0.09–0.10, pelagic bacterial carbon...

  3. Measurement of Electroweak Top Quark Production at {D\\O}

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Yun-Tse [Univ. of Rochester, NY (United States)

    2013-01-01

    We present a new model-independent measurement of the electroweak single top-quark production cross section in proton-antiproton (p- $\\bar{p}$) collisions at √s = 1.96 TeV in 9.7 fb-1 of integrated luminosity collected with the DØ detector.

  4. Does Input Quality Drive Measured Differences in Firm Productivity?

    DEFF Research Database (Denmark)

    Fox, Jeremy T.; Smeets, Valerie Anne Rolande

    2011-01-01

    One explanation for productivity dispersion is that the quality of inputs differs across firms. We add labor market history variables such as experience and firm and industry tenure, as well as general human capital measures such as schooling and sex. Adding these variables decreases the ratio...

  5. Performance measurement for product lifecycle management: a systemact literature review

    Directory of Open Access Journals (Sweden)

    Fernando Fonseca

    2012-01-01

    Full Text Available The aim of this study is to identify recommendations as well as the main performance indicator for developing a performance measurement system (PMS for product lifecycle management (PLM approach. Thus it was performed a systematic literature review that identified 22 recommendations and 296 performance indicators.

  6. Application of coincidence techniques to fusion product measurements

    International Nuclear Information System (INIS)

    Measurement of two products of a fusion reaction in coincidence is proposed. Possible detector arrays and sample count rates have been evaluated for reactions in the TFR and TEXT tokamaks and in the TFTR neutral beamlines. The count rates indicate that this method is feasible on existing devices

  7. Transaction costs and social networks in productivity measurement

    DEFF Research Database (Denmark)

    Henningsen, Geraldine; Henningsen, Arne; Henning, Christian H. C. A.

    2015-01-01

    and support. Hence, we use measures of a firm’s access to social networks as a proxy for the transaction costs the firm faces. We develop a microeconomic production model that takes into account transaction costs and networks. Using a data set of 384 Polish farms, we empirically estimate this model...

  8. Environmentally adjusted productivity measurement: an Australian case study.

    Science.gov (United States)

    Nanere, Marthin; Fraser, Iain; Quazi, Ali; D'Souza, Clare

    2007-10-01

    This paper critically examines various methods for estimating productivity incorporating environmental effects for the Australian agricultural sector. The agricultural sector has been selected because of its strategic position in the economy of Australia. The findings of this study indicate that the application of environmentally adjusted productivity methods is a credible approach to measure productivity, in the context of sustainable development. Although the empirical findings of this research are case study specific, the results provide evidence supporting the adoption of these techniques to other sectors of the economy when measuring productivity and needing to be cognisant of sustainable development. The findings suggest that adjusting for the environmental impacts of soil erosion can result in higher or lower agricultural productivity depending on the assumptions we make regarding damage costs of erosion. It is argued in this paper that, for soil erosion in Australia, assumptions yielding higher productivity (i.e., upwardly adjusted) are justified. Finally, the findings of this study and the use of the methods presented point to important gaps in data availability. This gap needs to be addressed by policy makers if sustainable development objectives are to be credibly assessed using these techniques.

  9. Data Interpretation Technology for Continuous Measurement Production Profile Logging

    Directory of Open Access Journals (Sweden)

    Junfeng Liu

    2014-05-01

    Full Text Available Up till now, there is no production logging data interpretation module in CIFLog, which is the 3rd generation well-logging software platform in China. So the situation has a strong impact on its promotion and utilization. In this paper, firstly, the authors introduce the characteristics of the existing and mature logging interpretation software, and design the data interpretation module functions for continuous measurement production profile logging based on JAVA-NetBeans. Secondly, the calculation methods of apparent fluid velocity, holdup, superficial velocity and flow rate of each phase are presented. Thirdly, eight module functions including wellbore message, curve value, physical parameters, and parameter settings are described. Finally, the authors has analyzed three-phase flow production profile logging data of X well using this module, which includes seven parameters of continuous measurement, and provided the result chart and table. In a word, the practice has proved that the module application effect is good.

  10. Measurements of heavy quark production via single leptons at PHENIX

    CERN Document Server

    Hornback, Donald

    2008-01-01

    The measurement of single leptons from the semi-leptonic decay of heavy-flavor hadrons has long been a means for studying heavy-quark production. PHENIX has measured single muons in pp collisions at forward rapidity and single electrons in both pp and AuAu collisions at mid-rapidity at sqrt(s_NN)=200 GeV. The most recent PHENIX single lepton results are presented in the context of state-of-the-art pQCD calculations. An updated azimuthal anisotropy, v2(pT), measurement for heavy-flavor single electrons in AuAu collisions is also presented.

  11. Photosynthetic bacterial growth and productivity under continuous illumination or diurnal cycles with olive mill wastewater as feedstock

    Energy Technology Data Exchange (ETDEWEB)

    Eroglu, Ela [Middle East Technical University, Dept. of Chemical Engineering, 06531, Ankara (Turkey); University of California, Dept. of Plant and Microbial Biology, Berkeley, CA 94720-3102 (United States); Gunduz, Ufuk; Yucel, Meral [Middle East Technical University, Dept. of Biology, 06531, Ankara (Turkey); Eroglu, Inci [Middle East Technical University, Dept. of Chemical Engineering, 06531, Ankara (Turkey)

    2010-06-15

    Photofermentative hydrogen production from olive mill wastewater by Rhodobacter sphaeroides O.U.001 was investigated under different regimes of illumination. The analysis included measurements of biomass accumulation, H{sub 2}-production, high-value bio-product accumulation (polyhydroxybutyrate and carotenoid) and measurements of the medium pH as a function of growth and productivity. Batch cultures were grown under continuous light (CL) or 12 h light/12 h dark (12L/12D) diurnal cycles. Growth under CL or 12L/12D cycles yielded about the same amount of biomass (0.5 g dry cell weight per L culture) and volume of H{sub 2} gas (50 ml H{sub 2} per L culture). On the other hand, 12L/12D cultures showed a pronounced lag in biomass and H{sub 2} accumulation. Advances described in the work would find application in lowering operational costs for hydrogen production by better management of the energy source and cheap feedstock utilization. Compare to CL, equivalent amount of hydrogen gas accumulation within shorter time interval denoted to have two times higher hydrogen production rate and light conversion efficiencies via diurnal cycles, which can yield 50% savings on consumed energy source. (author)

  12. Significant alteration of soil bacterial communities and organic carbon decomposition by different long-term fertilization management conditions of extremely low-productivity arable soil in South China.

    Science.gov (United States)

    Xun, Weibing; Zhao, Jun; Xue, Chao; Zhang, Guishan; Ran, Wei; Wang, Boren; Shen, Qirong; Zhang, Ruifu

    2016-06-01

    Different fertilization managements of red soil, a kind of Ferralic Cambisol, strongly affected the soil properties and associated microbial communities. The association of the soil microbial community and functionality with long-term fertilization management in the unique low-productivity red soil ecosystem is important for both soil microbial ecology and agricultural production. Here, 454 pyrosequencing analysis of 16S recombinant ribonucleic acid genes and GeoChip4-NimbleGen-based functional gene analysis were used to study the soil bacterial community composition and functional genes involved in soil organic carbon degradation. Long-term nitrogen-containing chemical fertilization-induced soil acidification and fertility decline and significantly altered the soil bacterial community, whereas long-term organic fertilization and fallow management improved the soil quality and maintained the bacterial diversity. Short-term quicklime remediation of the acidified soils did not change the bacterial communities. Organic fertilization and fallow management supported eutrophic ecosystems, in which copiotrophic taxa increased in relative abundance and have a higher intensity of labile-C-degrading genes. However, long-term nitrogen-containing chemical fertilization treatments supported oligotrophic ecosystems, in which oligotrophic taxa increased in relative abundance and have a higher intensity of recalcitrant-C-degrading genes but a lower intensity of labile-C-degrading genes. Quicklime application increased the relative abundance of copiotrophic taxa and crop production, although these effects were utterly inadequate. This study provides insights into the interaction of soil bacterial communities, soil functionality and long-term fertilization management in the red soil ecosystem; these insights are important for improving the fertility of unique low-productivity red soil. PMID:26486414

  13. Significant alteration of soil bacterial communities and organic carbon decomposition by different long-term fertilization management conditions of extremely low-productivity arable soil in South China.

    Science.gov (United States)

    Xun, Weibing; Zhao, Jun; Xue, Chao; Zhang, Guishan; Ran, Wei; Wang, Boren; Shen, Qirong; Zhang, Ruifu

    2016-06-01

    Different fertilization managements of red soil, a kind of Ferralic Cambisol, strongly affected the soil properties and associated microbial communities. The association of the soil microbial community and functionality with long-term fertilization management in the unique low-productivity red soil ecosystem is important for both soil microbial ecology and agricultural production. Here, 454 pyrosequencing analysis of 16S recombinant ribonucleic acid genes and GeoChip4-NimbleGen-based functional gene analysis were used to study the soil bacterial community composition and functional genes involved in soil organic carbon degradation. Long-term nitrogen-containing chemical fertilization-induced soil acidification and fertility decline and significantly altered the soil bacterial community, whereas long-term organic fertilization and fallow management improved the soil quality and maintained the bacterial diversity. Short-term quicklime remediation of the acidified soils did not change the bacterial communities. Organic fertilization and fallow management supported eutrophic ecosystems, in which copiotrophic taxa increased in relative abundance and have a higher intensity of labile-C-degrading genes. However, long-term nitrogen-containing chemical fertilization treatments supported oligotrophic ecosystems, in which oligotrophic taxa increased in relative abundance and have a higher intensity of recalcitrant-C-degrading genes but a lower intensity of labile-C-degrading genes. Quicklime application increased the relative abundance of copiotrophic taxa and crop production, although these effects were utterly inadequate. This study provides insights into the interaction of soil bacterial communities, soil functionality and long-term fertilization management in the red soil ecosystem; these insights are important for improving the fertility of unique low-productivity red soil.

  14. Production of glycolipidic bio surfactants by environment bacteria: diversity and physiological part; Production de biosurfactants glycolipidiques par les bacteries de l`environnement: diversite et role physiologique

    Energy Technology Data Exchange (ETDEWEB)

    Arino, S.

    1996-10-09

    About a hundred bacterial strains, isolated from soils, polluted or not by hydrocarbons, were tested for their capacity to excrete glycosides. The biggest productions were obtained for a soluble carbon source (glycerol) in a culture medium limited in the nitrogen source. In these conditions, 18 g/l of rhamnose lipids were produced by train Pseudomonas aeruginosa GL1 in a 200 h culture. Pseudomonas aeruginosa GL1, Cellulomonas celulans SA43 and Rhodococcus erythropolis DSM 43060 were studied in detail. The bio-surfactants produced were identified respectively as rhamnose lipids, oligosaccharide lipids and trehalose lipids, using various original analytical methods. Sugars and fatty acids composing these glycolipids had been shown to be usual components of the outer part of the cell wall in these microbial species. Moreover, cell hydrophobicity of the producing bacteria varied in time during culture. These results showed that both the cell wall and the extracellular glycolipids take part in the process of hydrocarbon uptake in the polluted environments. As other bacteria of the same species from different origins present the same characteristics, it may be concluded that glycolipid excretion does not constitute a specific response for hydrocarbon assimilation. In fact, a more general physiological role of glycolipids, concerning modifications of hydrophobic interfaces between the producing bacteria and their surrounding environment, could explain the production of glycolipids, and could also be utilized in hydrocarbon uptake. (author)

  15. Long-term organic-inorganic fertilization ensures great soil productivity and bacterial diversity after natural-to-agricultural ecosystem conversion.

    Science.gov (United States)

    Xun, Weibing; Xu, Zhihui; Li, Wei; Ren, Yi; Huang, Ting; Ran, Wei; Wang, Boren; Shen, Qirong; Zhang, Ruifu

    2016-09-01

    Natural ecosystems comprise the planet's wild plant and animal resources, but large tracts of land have been converted to agroecosystems to support the demand for agricultural products. This conversion limits the number of plant species and decreases the soil biological diversity. Here we used high-throughput 16S rRNA gene sequencing to evaluate the responses of soil bacterial communities in long-term converted and fertilized red soils (a type of Ferralic Cambisol). We observed that soil bacterial diversity was strongly affected by different types of fertilization management. Oligotrophic bacterial taxa demonstrated large relative abundances in chemically fertilized soil, whereas copiotrophic bacterial taxa were found in large relative abundances in organically fertilized and fallow management soils. Only organic-inorganic fertilization exhibited the same local taxonomic and phylogenetic diversity as that of a natural ecosystem. However, the independent use of organic or inorganic fertilizer reduced local taxonomic and phylogenetic diversity and caused biotic homogenization. This study demonstrated that the homogenization of bacterial communities caused by natural-to-agricultural ecosystem conversion can be mitigated by employing rational organic-inorganic fertilization management. PMID:27572510

  16. Long-term organic-inorganic fertilization ensures great soil productivity and bacterial diversity after natural-to-agricultural ecosystem conversion.

    Science.gov (United States)

    Xun, Weibing; Xu, Zhihui; Li, Wei; Ren, Yi; Huang, Ting; Ran, Wei; Wang, Boren; Shen, Qirong; Zhang, Ruifu

    2016-09-01

    Natural ecosystems comprise the planet's wild plant and animal resources, but large tracts of land have been converted to agroecosystems to support the demand for agricultural products. This conversion limits the number of plant species and decreases the soil biological diversity. Here we used high-throughput 16S rRNA gene sequencing to evaluate the responses of soil bacterial communities in long-term converted and fertilized red soils (a type of Ferralic Cambisol). We observed that soil bacterial diversity was strongly affected by different types of fertilization management. Oligotrophic bacterial taxa demonstrated large relative abundances in chemically fertilized soil, whereas copiotrophic bacterial taxa were found in large relative abundances in organically fertilized and fallow management soils. Only organic-inorganic fertilization exhibited the same local taxonomic and phylogenetic diversity as that of a natural ecosystem. However, the independent use of organic or inorganic fertilizer reduced local taxonomic and phylogenetic diversity and caused biotic homogenization. This study demonstrated that the homogenization of bacterial communities caused by natural-to-agricultural ecosystem conversion can be mitigated by employing rational organic-inorganic fertilization management.

  17. Bacterial Cellulose Production by Fruit Juice Fermentation%果汁发酵生产细菌纤维素

    Institute of Scientific and Technical Information of China (English)

    张俊娜; 甘峰; 李志西; 林德慧; 潘凯旋

    2012-01-01

    为提高果汁发酵生产细菌纤维素的产量,开发特色纤维素功能性食品,以葡糖醋杆菌CGMCC 3917为实验菌种,以苹果汁和梨汁为发酵培养基生产细菌纤维素(BC),研究果汁用量和酵母膏添加量对细菌纤维素产量的影响,比较分析两种果汁生产的细菌纤维素在产量、结构和性质方面的差别。结果表明:梨汁发酵生产的细菌纤维素产量明显高于苹果汁,可达46.343g/100mL;其BC干膜复水率显著高于苹果汁,BC干膜的总糖含量稍高于苹果汁。两种果汁发酵生产的细菌纤维素在湿膜持水量及干膜的纤维素含量、蛋白质含量、脂肪含量以及微观结构上没有明显差异。%To improve bacterial cellulose (BC) production and to develop specific cellulose functional food products, BC was prepared from the fermentation of apple juice or pear juice by Gluconoacetobacter hanseni CGMCC 3917. The influence of fruit juice dilution and amount of added yeast extract on BC yield was evaluated. Meanwhile, further studies were done to investigate the influence of fruit juice type on BC production, structure and properties. The results showed that pear juice provided more production of BC than apple juice, reaching 46.343 g/100 mL. Moreover, dried BC membranes from pear juice showed a significantly higher rehydration rate, and a slightly higher total sugar content than those from apple juice. There were no pronounced differences in water content of wet BC membranes and cellulose, protein and fat contents and microstructure of dry BC membranes between both fruit juices.

  18. Incidence of spontaneous bacterial peritonitis in patients with ascites. Diagnostic value of white blood cell count and pH measurement in ascitic fluid

    DEFF Research Database (Denmark)

    Storgaard, J S; Svendsen, Jesper Hastrup; Hegnhøj, J;

    1991-01-01

    During a 21-month period, 65 consecutive patients admitted with ascites were included in a prospective study of the incidence of spontaneous bacterial peritonitis, and paracentesis was performed on admission. The ascitic fluid was cultured, ascitic leucocytes were counted and pH was measured....... Bacterial growth was found in five patients with chronic liver disease, who were diagnosed as having spontaneous bacterial peritonitis (SBP), since no intra-abdominal focus could be demonstrated. Thus, the incidence of SBP in this material was 7.7% (95% confidence limits: 2.5-17%). SBP was caused...... of the patients with SBP. In contrast to several previous studies, neither ascites pH nor ascites leucocyte counts were any help in obtaining a rapid diagnosis. Survival time of patients with SBP was significantly shorter than of patients without SBP....

  19. Measurement of cosmogenic radioactive products in xenon and copper

    Science.gov (United States)

    Piastra, Francesco

    2016-02-01

    Rare events searches, such as direct dark matter detection or neutrinoless double beta decay (0vββ) observation, using liquid xenon as target and detection medium require ultralow background to fully exploit the physics potential. Cosmogenic activation of the detector components, and even more importantly, of the xenon itself might have undesired impact on the background and the final sensitivity of the experiment. Since no measurement of cosmogenic activation of xenon was present in literature so far, we performed such a measurement exposing of a natural xenon sample to the cosmic radiation at the Jungfraujoch research station at an altitude of 3470 m above sea level for 245 days. This study was complemented with a ultra pure copper sample that was activated together with the xenon. We directly observed, with gamma-ray spectrometry, the production of 7Be, 101Rh, 125Sb, 126I and 127Xe in xenon, out of which only 125 Sb could potentially lead to a background relevant for multi-ton scale direct dark matter search. The production rates for five out of eight radioactive isotopes in copper are in good agreement with the only dedicated measurement present in literature. The production rates measured for both samples were compared with the predictions obtained with commonly used software packages. The latter showed a systematic under-estimation, especially for xenon.

  20. Profit and Risk Measures in Oil Production Optimization

    DEFF Research Database (Denmark)

    Capolei, Andrea; Foss, Bjarne; Jørgensen, John Bagterp

    2015-01-01

    In oil production optimization, we usually aim to maximize a deterministic scalar performance index such as the profit over the expected reservoir lifespan. However, when uncertainty in the parameters is considered, the profit results in a random variable that can assume a range of values dependi...... pro and cons for each of them. Finally, among the presented risk measures, we identify two of them as appropriate risk measures when minimizing the risk....... on the value of the uncertain parameters. In this case, a problem reformulation is needed to properly define the optimization problem. In this paper we describe the concept of risk and we explore how to handle the risk by using appropriate risk measures. We provide a review on various risk measures reporting...

  1. Measuring individual research productivity: A review and development of the integrated research productivity index.

    Science.gov (United States)

    Duffy, Ryan D; Martin, Helena M; Bryan, Nicole A; Raque-Bogdan, Trisha L

    2008-10-01

    The purpose of the present study was to investigate methods of measuring individual research productivity for counseling psychologists. Using the 60 members of the Journal of Counseling Psychology editorial board, the authors computed a comparison of 6 popular indices of productivity, revealing considerable levels of positive skewness, kurtosis, and overlap with each other. Combining the strengths of the 6 indices, the authors developed a new productivity index entitled the Integrated Research Productivity Index (IRPI). The IRPI measures individual productivity by statistically combining an individual's author-weighted publications, average times cited by other publications, and years since first publication into a comprehensive score. Productivity values and IRPI scores for 3 groups of counseling psychologists (Tyler Award recipients, Kuder Award recipients, and Division 17 Presidents) were computed to provide evidence of discriminant validity among the indices. In contrast to the other measures examined, the IRPI accounts for productivity per year and years in the field and assesses mean citation count per article as opposed to total citation count, thus yielding similar scores for Tyler (lifetime) and Kuder (early career) research award recipients. (PsycINFO Database Record (c) 2010 APA, all rights reserved). PMID:22017558

  2. Latest LHCb measurements of Electroweak Boson Production in Run-1

    CERN Document Server

    CERN. Geneva

    2015-01-01

    We present the latest LHCb measurements of forward Electroweak Boson Production using proton-proton collisions recorded in LHC Run-1. The seminar shall discuss measurements of the 8 TeV W & Z boson production cross-sections. These results make use of LHCb's excellent integrated luminosity determination to provide constraints on the parton distribution functions which describe the inner structure of the proton. These LHCb measurements probe a region of phase space at low Bjorken-x where the other LHC experiments have limited sensitivity. We also present measurements of cross-section ratios, and ratios of results in 7 TeV and 8 TeV proton-proton collisions. These results provide precision tests of the Standard Model. The seminar shall also present a measurement of the forward-backward asymmetry (A_FB) in Z boson decays to two muons. This result allows for precision tests of the coupling of the Z boson to left and right handed particles, providing sensitivity to the effective weak mixing angle (...

  3. Measurement of Charmed Particle Production in Hadronic Reactions

    CERN Multimedia

    2002-01-01

    The aim of the experiment is to measure the production cross-section for charmed particles in hadronic reactions, study their production mechanism, and search for excited charmed hadrons.\\\\ \\\\ Charmed Mesons and Baryons will be measured in @p and p interactions on Beryllium between 100 and 200 GeV/c. The trigger will be on an electron from the leptonic decay of one charmed particle by signals from the Cerenkov counter (Ce), the electron trigger calorimeter (eCal), scintillation counters, and proportional wire chambers. The accompanying charmed particle will be measured via its hadronic decay in a two-stage magnetic spectrometer with drift chambers (arms 2, 3a, 3b, 3c), two large-area multicell Cerenkov counters (C2, C3) and a large-area shower counter (@g-CAL). The particles which can be measured and identified include @g, e, @p@+, @p|0, K@+, p, @* so that a large number of hadronic decay modes of charmed particles can be studied. \\\\ \\\\ A silicon counter telescope with 5 @mm spatial resolution will measure se...

  4. Link between Domoic Acid Production and Cell Physiology after Exchange of Bacterial Communities between Toxic Pseudo-nitzschia multiseries and Non-Toxic Pseudo-nitzschia delicatissima

    Directory of Open Access Journals (Sweden)

    Aurélie Lelong

    2014-06-01

    Full Text Available Bacteria are known to influence domoic acid (DA production by Pseudo-nitzschia spp., but the link between DA production and physiology of diatoms requires more investigation. We compared a toxic P. multiseries to a non-toxic P. delicatissima, investigating links between DA production, physiological parameters, and co-occurring bacteria. Bacterial communities in cultures of both species were reduced by antibiotic treatment, and each of the diatoms was inoculated with the bacterial community of the other species. The physiology of P. delicatissima was minimally affected by the absence of bacteria or the presence of alien bacteria, and no DA was detected. P. multiseries grew faster without bacteria, did not produce a significant amount of DA, and exhibited physiological characteristics of healthy cells. When grown with alien bacteria, P. multiseries did not grow and produced more DA; the physiology of these cells was affected, with decreases in chlorophyll content and photosynthetic efficiency, an increase in esterase activity, and almost 50% mortality of the cells. The alien bacterial community had morphological and cellular characteristics very different from the original bacteria, and the number of free-living bacteria per algal cell was much higher, suggesting the involvement of bacteria in DA production.

  5. Precision Measurements of Top Quark Production with the ATLAS Detector

    CERN Document Server

    Stolte, Philipp; The ATLAS collaboration

    2016-01-01

    The top quark is the heaviest known fundamental particle. It is the only quark that decays before it hadronises which gives us the unique opportunity to probe the properties of bare quarks and to test perturbative QCD. This overview will focus on a few recent precision top quark measurements by the ATLAS Collaboration at the LHC: Fiducial top pair and single top production cross-sections including differential distributions will be presented and compared with QCD predictions. The results include the first top quark measurements at 13 TeV using data from LHC Run 2.

  6. Precision measurements of top quark production with the ATLAS detector

    CERN Document Server

    Stolte, Philipp; The ATLAS collaboration

    2016-01-01

    The top quark is the heaviest known fundamental particle. As it is the only quark that decays before it hadronizes, this gives us the unique opportunity to probe the properties of bare quarks and to test perturbative QCD. This talk will focus on a few recent precision top quark measurements by the ATLAS Collaboration: fiducial top pair and single top production cross sections including differential distributions will be presented and compared with QCD predictions. The results include the first top quark measurements at 13 TeV using data from LHC run 2.

  7. Measurement of beauty production in DIS and extraction at ZEUS

    Energy Technology Data Exchange (ETDEWEB)

    Abramowicz, H.; Ingbir, R.; Kananov, S.; Levy, A.; Stern, A. [Tel Aviv University, Raymond and Beverly Sackler Faculty of Exact Sciences, School of Physics, Tel Aviv (Israel); Abt, I.; Caldwell, A.; Kollar, D.; Reisert, B.; Schmidke, W.B. [Max-Planck-Institut fuer Physik, Muenchen (Germany); Adamczyk, L.; Bold, T.; Gach, G.; Grabowska-Bold, I.; Kisielewska, D.; Przybycien, M.; Suszycki, L. [AGH-University of Science and Technology, Faculty of Physics and Applied Computer Science, Cracow (Poland); Adamus, M.; Plucinski, P.; Tymieniecka, T. [Institute for Nuclear Studies, Warsaw (Poland); Aggarwal, R.; Kaur, M.; Kaur, P.; Singh, I. [Panjab University, Department of Physics, Chandigarh (India); Antonelli, S.; Basile, M.; Bindi, M.; Cifarelli, L.; Contin, A.; De Pasquale, S.; Sartorelli, G.; Zichichi, A. [University Bologna (Italy); INFN Bologna, Bologna (Italy); Antonioli, P.; Bari, G.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Cindolo, F.; Corradi, M.; Iacobucci, G.; Margotti, A.; Nania, R.; Polini, A. [INFN Bologna, Bologna (Italy); Antonov, A.; Dolgoshein, B.A.; Gladkov, D.; Sosnovtsev, V.; Stifutkin, A.; Suchkov, S. [Moscow Engineering Physics Institute, Moscow (Russian Federation); Arneodo, M.; Ruspa, M. [Universita del Piemonte Orientale, Novara (Italy); INFN, Torino (Italy); Aushev, V.; Aushev, Y.; Borodin, M.; Gogota, O.; Kadenko, I.; Korol, I.; Kuprash, O.; Lontkovskyi, D.; Makarenko, I.; Onishchuk, Yu.; Salii, A.; Tomalak, O.; Viazlo, V.; Volynets, O.; Zenaiev, O.; Zhmak, N.; Zolko, M. [National Academy of Sciences, and Kiev National University, Institute for Nuclear Research, Kiev (Ukraine); Bachynska, O.; Behnke, O.; Behr, J.; Behrens, U.; Blohm, C.; Borras, K.; Bot, D.; Ciesielski, R.; Coppola, N.; Fang, S.; Geiser, A.; Goettlicher, P.; Grebenyuk, J.; Gregor, I.; Haas, T.; Hain, W.; Huettmann, A.; Januschek, F.; Kahle, B.; Katkov, I.I.; Klein, U.; Koetz, U.; Kowalski, H.; Libov, V.; Lisovyi, M.; Lobodzinska, E. [and others

    2010-10-15

    Beauty production in deep inelastic scattering with events in which a muon and a jet are observed in the final state has been measured with the ZEUS detector at HERA using an integrated luminosity of 114 pb{sup -1}. The fraction of events with beauty quarks in the data was determined using the distribution of the transverse momentum of the muon relative to the jet. The cross section for beauty production was measured in the kinematic range of photon virtuality, Q{sup 2}>2 GeV{sup 2}, and inelasticity, 0.05

  8. Measurement of isolated photon production in deep inelastic ep scattering

    Energy Technology Data Exchange (ETDEWEB)

    Chekanov, S.; Derrick, M.; Magill, S. [Argonne National Lab., Argonne, IL (US)] (and others)

    2009-09-15

    Isolated photon production in deep inelastic ep scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 320 pb{sup -1}. Measurements were made in the isolated-photon transverse-energy and pseudo- rapidity ranges 45 GeV. Differential cross sections are presented for inclusive isolated photon production as functions of Q{sup 2}, x, E{sub T}{sup {gamma}} and {eta}{sup {gamma}}. Leading-logarithm parton-shower Monte Carlo simulations and perturbative QCD predictions give a reasonable description of the data over most of the kinematic range. (orig.)

  9. LEP measurements on production, mass, lifetime of beauty particles

    International Nuclear Information System (INIS)

    Present knowledge about the individual properties of the different beauty particles is discussed using the results of the LEP experiments. Individual lifetimes for Bd0 and B+ are found to be equal within 10% whilst a 15% precision is reached for Bs0 and Λb. The Λb lifetime is found to be smaller than τB+ with a 2.7 σ significance. The production rate of each of these particles is measured at the 20% level. Preliminary evidence for Ξb production has been reported. Finally, the Bs0 meson mass has been measured to be 5373 ± 4 MeV/c2. (author) 24 refs., 9 figs., 5 tabs

  10. Measurements of $\\Upsilon$ Production and Nuclear Modification Factor at STAR

    CERN Document Server

    Kesich, Anthony

    2012-01-01

    Thermal suppression of quarkonium production in heavy-ion collisions, due to Debye screening of the quark-antiquark potential, has been proposed as a clear signature of Quark-Gluon Plasma (QGP) formation. At RHIC energies, the $\\Upsilon$ meson is a clean probe of the early system due to negligible levels of enhancement from \\bbbar recombination and non-thermal suppression from co-mover absorption. We report on our measurement of the $\\Upsilon \\to e^+ e^-$ cross section in Au+Au collisions at $\\sqrt{s_{NN}}$=200 GeV. We compute the Nuclear Modification Factor by comparing these results to new p+p measurements from 2009 (21 pb$^{-1}$ in 2009 compared to 7.9 pb$^{-1}$ in 2006). In order to have a complete assessment of both hot and cold nuclear matter effects on Upsilon production we also report on results from d+Au collisions.

  11. Di-boson production measurements with the ATLAS detector

    CERN Document Server

    Chevalier, Laurent

    2015-01-01

    This talk covers the results of the measurements of diboson production cross sections in proton- proton interactions at 7 TeV in 2011 and at 8 TeV in 2012, performed by the ATLAS experiment. The cross sections are measured in phase space regions defined by the decay kinematics, the detector acceptance and then extrapolated to the full phase space. Cross sections for VV (V=W, Z, γ) production in the leptonic or semileptonic channels are compared to (N)NLO predictions of the Standard Model. Kinematic spectra are used to place constraints on anomalous triple-gauge-boson couplings. All cross sections are in agreement with the Standard Model predictions. No experimental evidence is found of anomalous triple-gauge-boson couplings. PACS: 14.70.-e Gauge bosons.

  12. Sampling the Fermi statistics and other conditional product measures

    CERN Document Server

    Gaudilliere, Alexandre

    2009-01-01

    Through a Metropolis-like algorithm with single step computational cost of order one, we build a Markov chain that relaxes to the canonical Fermi statistics for k non-interacting particles among m energy levels. Uniformly over the temperature as well as the energy values and degeneracies of the energy levels we give an explicit upper bound with leading term km(ln k) for the mixing time of the dynamics. We obtain such construction and upper bound as a special case of a general result on (non-homogeneous) products of ultra log-concave measures (like binomial or Poisson laws) with a global constraint. As a consequence of this general result we also obtain a disorder-independent upper bound on the mixing time of a simple exclusion process on the complete graph with site disorder. This general result is based on an elementary coupling argument and extended to (non-homogeneous) products of log-concave measures.

  13. ATLAS reach for Quarkonium production and polarization measurements

    International Nuclear Information System (INIS)

    The ATLAS detector at CERN's LHC is preparing to take data from the first proton-proton collisions expected in the next few months. We report on the analysis of simulated data samples for production of heavy Quarkonium states J/ψ and Y, corresponding to an integrated luminosity of 10pb-1 with center of mass energy of 14 TeV expected at the early ATLAS data. We review various aspects of prompt Quarkonium production at LHC: the accessible ranges in transverse momentum and pseudorapidity, spin alignment of vector states, separation of color octet and color singlet production mechanism and feasibility of observing radiative decays χc and χb decays. Strategies of various measurements are outlined and methods of separating promptly produced J/ψ and Y mesons from various backgrounds are discussed.

  14. NOx from cement production - reduction by primary measures

    DEFF Research Database (Denmark)

    Jensen, Lars Skaarup

    1999-01-01

    This thesis comprises an investigation of the mechanisms involved in forming and reducing NOx in kiln systems for cement production. Particularly the mechanisms forming and reducing NOx in calciners are dealt with in detail, as altered calciner design and operation are most applicable...... to controlling NOx emission by primary measures. The main focus has been on elucidating NOx formation and reduction mechanisms involving reactions of char, and on determining their relative importance in calciners.The first three chapters give an introduction to cement production, combustion and NOx. In modern...... cement production processes cement is typically produced by thermally treating a mixture of limestone and clay minerals in kiln systems consisting of a rotary kiln and a calciner. Clinker burning at a temperature of about 1450 °C takes place in the internally fired rotary kiln and calcination, which...

  15. A contribution for the understanding and measurement of production sustainability

    OpenAIRE

    Lago, David Rodríguez

    2015-01-01

    Dissertação de mestrado integrado em Engenharia e Gestão Industrial Sustainability is an imperative of present and future production activity. Sustainability is concerned with the environment protection, safety and welfare of present and future generations. Business success, both in manufacturing and services, must be measured against results contributing to sustainability. This means that business practices must be based on strategies that assertively address not only economic...

  16. Farm production diversity and dietary quality: Linkages and measurement issues

    OpenAIRE

    Sibhatu, Kibrom T.; Qaim, Matin

    2016-01-01

    Recent research has analyzed whether higher levels of farm production diversity contribute to improved dietary quality in smallholder households. We add to this literature by using different indicators, thus testing the robustness of previous findings and helping to better understand the underlying linkages. The analysis builds on data from Indonesia, Kenya, and Uganda. Farm diversity measured through a simple species count has a small positive effect on dietary quality, either expressed in t...

  17. Classifying Floating Potential Measurement Unit Data Products as Science Data

    Science.gov (United States)

    Coffey, Victoria; Minow, Joseph

    2015-01-01

    We are Co-Investigators for the Floating Potential Measurement Unit (FPMU) on the International Space Station (ISS) and members of the FPMU operations and data analysis team. We are providing this memo for the purpose of classifying raw and processed FPMU data products and ancillary data as NASA science data with unrestricted, public availability in order to best support science uses of the data.

  18. Resistance Induction and Enhanced Tuber Production by Pre-inoculation with Bacterial Strains in Potato Plants against Phytophthora infestans

    OpenAIRE

    Kim, Hyo-Jeong; Jeun, Yong-Chull

    2006-01-01

    Efficacy of resistance induction by the bacterial isolates Pseudomonas putida (TRL2-3), Micrococcus luteus (TRK2-2) and Flexibacteraceae bacterium (MRL412), which were isolated from the rhizosphere of plants growing in Jeju Mountain, were tested in a greenhouse. The disease severity caused by Phytophthora infestans was effectively reduced in the potato plants pre-inoculated with bacterial isolates compared with those of the untreated control plants growing in a greenhouse. In order to estimat...

  19. Analysis of the Impact of Rosuvastatin on Bacterial Mevalonate Production Using a UPLC-Mass Spectrometry Approach.

    Science.gov (United States)

    Nolan, J A; Kinsella, M; Hill, C; Joyce, S A; Gahan, C G M

    2016-07-01

    Statins are widely prescribed cholesterol-lowering medications and act through inhibition of the human enzyme 3-methylglutaryl coenzyme A reductase (HMG-R) which produces mevalonate (MVAL), a key substrate for cholesterol biosynthesis. Some important microbial species also express an isoform of HMG-R; however, the nature of the interaction between statins and bacteria is currently unclear and studies would benefit from protocols to quantify MVAL in complex microbial environments. The objective of this study was to develop a protocol for the analytical quantification of MVAL in bacterial systems and to utilise this approach to analyse the effects of Rosuvastatin (RSV) on bacterial MVAL formation. To determine the effective concentration range of RSV, we examined the dose-dependent inhibition of growth in the HMG-R(+) bacterial pathogens Listeria monocytogenes, Staphylococcus aureus and Enterococcus faecium at various concentrations of pure RSV. Growth inhibition generally correlated with a reduction in bacterial MVAL levels, particularly in culture supernatants at high RSV concentrations, as determined using our ultra-performance liquid chromatography mass spectrometry protocol. This work therefore outlines a refined protocol for the analysis of MVAL in microbial cultures and provides evidence for statin-mediated inhibition of bacterial HMG-R. Furthermore, we show that MVAL is readily transported and secreted from bacterial cells into the growth media. PMID:26960292

  20. Bacterial incorporation of tritiated thymidine and populations of bacteriophagous fauna in the rhizosphere of wheat

    DEFF Research Database (Denmark)

    Christensen, Henrik; Griffiths, Bryan; Christensen, Søren

    1992-01-01

    Bacterial and microfaunal populations, and bacterial productivity measured by tritiated thymidine (3HTdr) incorporation, in the rhizosphere of wheat seedlings were measured. Soil from planted pots was fractionated into rhizosphere and non-rhizosphere (bulk) soil, while unplanted soil was taken fr...

  1. Effects of dietary inulin on bacterial growth, short-chain fatty acid production and hepatic lipid metabolism in gnotobiotic mice.

    Science.gov (United States)

    Weitkunat, Karolin; Schumann, Sara; Petzke, Klaus Jürgen; Blaut, Michael; Loh, Gunnar; Klaus, Susanne

    2015-09-01

    In literature, contradictory effects of dietary fibers and their fermentation products, short-chain fatty acids (SCFA), are described: On one hand, they increase satiety, but on the other hand, they provide additional energy and promote obesity development. We aimed to answer this paradox by investigating the effects of fermentable and non-fermentable fibers on obesity induced by high-fat diet in gnotobiotic C3H/HeOuJ mice colonized with a simplified human microbiota. Mice were fed a high-fat diet supplemented either with 10% cellulose (non-fermentable) or inulin (fermentable) for 6 weeks. Feeding the inulin diet resulted in an increased diet digestibility and reduced feces energy, compared to the cellulose diet with no differences in food intake, suggesting an increased intestinal energy extraction from inulin. However, we observed no increase in body fat/weight. The additional energy provided by the inulin diet led to an increased bacterial proliferation in this group. Supplementation of inulin resulted further in significantly elevated concentrations of total SCFA in cecum and portal vein plasma, with a reduced cecal acetate:propionate ratio. Hepatic expression of genes involved in lipogenesis (Fasn, Gpam) and fatty acid elongation/desaturation (Scd1, Elovl3, Elovl6, Elovl5, Fads1 and Fads2) were decreased in inulin-fed animals. Accordingly, plasma and liver phospholipid composition were changed between the different feeding groups. Concentrations of omega-3 and odd-chain fatty acids were increased in inulin-fed mice, whereas omega-6 fatty acids were reduced. Taken together, these data indicate that, during this short-term feeding, inulin has mainly positive effects on the lipid metabolism, which could cause beneficial effects during obesity development in long-term studies.

  2. Effects of dietary inulin on bacterial growth, short-chain fatty acid production and hepatic lipid metabolism in gnotobiotic mice.

    Science.gov (United States)

    Weitkunat, Karolin; Schumann, Sara; Petzke, Klaus Jürgen; Blaut, Michael; Loh, Gunnar; Klaus, Susanne

    2015-09-01

    In literature, contradictory effects of dietary fibers and their fermentation products, short-chain fatty acids (SCFA), are described: On one hand, they increase satiety, but on the other hand, they provide additional energy and promote obesity development. We aimed to answer this paradox by investigating the effects of fermentable and non-fermentable fibers on obesity induced by high-fat diet in gnotobiotic C3H/HeOuJ mice colonized with a simplified human microbiota. Mice were fed a high-fat diet supplemented either with 10% cellulose (non-fermentable) or inulin (fermentable) for 6 weeks. Feeding the inulin diet resulted in an increased diet digestibility and reduced feces energy, compared to the cellulose diet with no differences in food intake, suggesting an increased intestinal energy extraction from inulin. However, we observed no increase in body fat/weight. The additional energy provided by the inulin diet led to an increased bacterial proliferation in this group. Supplementation of inulin resulted further in significantly elevated concentrations of total SCFA in cecum and portal vein plasma, with a reduced cecal acetate:propionate ratio. Hepatic expression of genes involved in lipogenesis (Fasn, Gpam) and fatty acid elongation/desaturation (Scd1, Elovl3, Elovl6, Elovl5, Fads1 and Fads2) were decreased in inulin-fed animals. Accordingly, plasma and liver phospholipid composition were changed between the different feeding groups. Concentrations of omega-3 and odd-chain fatty acids were increased in inulin-fed mice, whereas omega-6 fatty acids were reduced. Taken together, these data indicate that, during this short-term feeding, inulin has mainly positive effects on the lipid metabolism, which could cause beneficial effects during obesity development in long-term studies. PMID:26033744

  3. Airborne measurements of fission product fall-out

    Energy Technology Data Exchange (ETDEWEB)

    Hovgaard, J.; Korsbech, U.

    1992-12-01

    During 1993 the Danish Emergency Management Agency will install an airborne [gamma]-ray detector system for area survey of contamination with radioactive nuclides - primarily fission products that may be released during a heavy accident at a nuclear power plant or from accidents during transport of radioactive material. The equipment is based on 16 liter NaI(TI) crystals and multichannel analysers from Exploranium (Canada). A preliminary investigation of the possibilities for detection of low and high level contamination - and the problems that may be expected during use of the equipment, and during interpretation of the measured data, is described. Several days after reactor shut-down some of the nuclides can be identified directly from the measured spectrum, and contamination levels may be determined within a factor two. After several weeks, most fission products have decayed. Concentrations and exposure rates can be determined with increasing accuracy as time passes. Approximate calibration of the equipment for measurements of surface contamination and natural radioactivity can be performed in the laboratory. Further checks of equipment should include accurate measurements of the spectrum resolution. Detectors should be checked individually, and all together. Further control of dead time and pulse pile-up should be performed. Energy calibration, electronics performance and data equipment should be tested against results from the original calibration. (AB).

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

    OpenAIRE

    Crispin Humberto Garcia-Cruz; Fernanda M. P. G. Ernandes

    2005-01-01

    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 flavo...

  5. Membrane fluidity as a factor in production and stability of bacterial ice nuclei active at high subfreezing temperatures.

    Science.gov (United States)

    Lindow, S E

    1995-06-01

    Detailed measurements were made of the rate of appearance of bacterial ice nuclei upon cooling of suspensions of Pseudomonas syringae cells and the disappearance of ice nuclei upon warming of the cells before assay for ice nucleation activity. While no substantial change in numbers of ice nuclei active at either -5 or at -9 degrees C was observed in cells that were grown at temperatures lower than 24 degrees C and cooled to 21 degrees C before assay, large increases in -5 but not -9 degrees C ice nuclei were observed in cells grown at temperatures greater than 24 degrees C. Ice nucleation activity of cells subjected to a decrease in temperature before assay increased immediately upon temperature shift, but 8 to 12 min was required before maximum rates of increase in numbers of ice nuclei were observed. The rate of appearance of ice nuclei in cell suspensions incubated at relatively cold temperatures prior to assay was substantially less than those incubated at temperatures approaching 24 degrees C. Cells rapidly lost ice nucleation activity when warmed to above 27 degrees C before assay; the rate of loss of ice nuclei in cells grown at a given temperature increased rapidly as the temperature to which they were warmed before assay increased. Ice nuclei disappeared most rapidly when cells grown at low temperatures were warmed before assay, suggesting that ice nucleus stability was lower in highly fluid membranes. The logarithm of the half-life of ice nuclei in cells was directly related to the concentration of the membrane fluidizing agent, 2-phenethyl alcohol, in which they were suspended. PMID:7781327

  6. Particle Production Measurements using the MIPP Detector at Fermilab

    CERN Document Server

    Mahajan, Sonam

    2013-01-01

    The Main Injector Particle Production (MIPP) experiment is a fixed target hadron production experiment at Fermilab. It measures particle production in interactions of 120 GeV/c primary protons from the Main Injector and secondary beams of $\\pi^{\\pm}, \\rm{K}^{\\pm}$, p and $\\bar{\\rm{p}}$ from 5 to 90 GeV/c on nuclear targets which include H, Be, C, Bi and U, and a dedicated run with the NuMI target. MIPP is a high acceptance spectrometer which provides excellent charged particle identification using Time Projection Chamber (TPC), Time of Flight (ToF), multicell Cherenkov (CKOV), Ring Imaging Cherenkov (RICH) detectors, and Calorimeter for neutrons. We present inelastic cross section measurements for 58 and 85 GeV/c p-H interactions, and 58 and 120 GeV/c p-C interactions. A new method is described to account for the low multiplicity inefficiencies in the interaction trigger using KNO scaling. Inelastic cross sections as a function of multiplicity are also presented. The MIPP data are compared with the Monte Carl...

  7. Measurement of Heavy Flavor and Quarkonia Production by PHENIX

    CERN Document Server

    Brooks, M L

    2008-01-01

    Heavy quarks (charm and bottom) are good probes of the hot and dense medium created in relativistic heavy ion collisions since they are mainly generated at the beginning of collisions and interact with the media in all collision stages. In addition, heavy flavor quarkonia production is thought to be uniquely sensitive to the deconfined medium of the Quark Gluon Plasma (QGP) through color screening. Heavy quark production has been studied by the PHENIX experiment at RHIC via measurements of single leptons from semi-leptonic decays in both the electron channel at mid-rapidity and in the muon channel at forward-rapidity. Large suppression and azimuthal anisotropy of single electrons have been observed in Au+Au collisions at sqrt(s) = 200 GeV. These results suggest a large energy loss and flow of the heavy quarks in the hot, dense matter. The PHENIX experiment has also measured J/psi production up to sqrt(s) = 200 GeV in p+p, d+Au, Cu+Cu and Au+Au collisions, both at mid (|y|<0.35) and forward (1.2<|y|<2...

  8. Comparison of bacterial biomass and PRP production between different isolation of Haemophilus influenza type-b (Hib under different culture conditions

    Directory of Open Access Journals (Sweden)

    Hadi, A.

    2011-06-01

    Full Text Available Heamophilus influenzae type-b (Hib is a gram - negative pleomorphic bacterium that causes meningitis infections in children with the age of less than 5 years particularly in two years old infants. In the present study various isolates of Heamophilus influenzae from infants suspected to meningitis were collected, identified, characterized and were used throughout our experiments. Different culture media namely Brain Heart Infusion Broth (BHIB, Tryptic Soy Broth (TSB and GC medium Base (GCB which this medium was modified and prepared in our own laboratory, were compared to determine the highest bacterial yield. All media were added supplements 10mg/ml hemin & 0.01/ml IsovitaleX containing V factor. The bacterial yield for all Hib strains present in our laboratory were measured with an initial inoculums of 104 cfu per ml. The result showed very closed amount of biomass for all isolates however, GCB had slightly higher yield and ultimately we chose this medium for cultivation and extraction of capsular polysaccharide (CPS-b. In our laboratory we have adapted the PRP production according to our technical and instrumental availabilities which exists in our laboratories replacing ultra centrifugation to phenol chloroform to remove contaminants like endotoxin and proteins to the minimum level and also decreased the number of some chemical treatments while some steps were added in purification process. Our study showed although there were not significant differences between the PRP extract of the three isolates with average amount of 108 mg/lit, however, isolate ATCC10210 (ATF2 showed the highest amount with 192mg/lit and the least PRP was produced by isolate H.inf.1, with 16 mg/lit. It seems that the data can be categorized to a normal distribution with the mean of 106.4 and standard deviation of 6.25. This result was confirmed by one sample kolmogorov-Smirnov test, hence the PRP ≥192 mg/lit is statistically significant at a significant level of α =0

  9. Statistical analysis of long- and short-range forces involved in bacterial adhesion to substratum surfaces as measured using atomic force microscopy.

    Science.gov (United States)

    Chen, Yun; Busscher, Henk J; van der Mei, Henny C; Norde, Willem

    2011-08-01

    Surface thermodynamic analyses of microbial adhesion using measured contact angles on solid substrata and microbial cell surfaces are widely employed to determine the nature of the adhesion forces, i.e., the interplay between Lifshitz-van der Waals and acid-base forces. While surface thermodynamic analyses are often viewed critically, atomic force microscopy (AFM) can also provide information on the nature of the adhesion forces by means of Poisson analysis of the measured forces. This review first presents a description of Poisson analysis and its underlying assumptions. The data available from the literature for different combinations of bacterial strains and substrata are then summarized, leading to the conclusion that bacterial adhesion to surfaces is generally dominated by short-range, attractive acid-base interactions, in combination with long-range, weaker Lifshitz-van der Waals forces. This is in line with the findings of surface thermodynamic analyses of bacterial adhesion. Comparison with single-molecule ligand-receptor forces from the literature suggests that the short-range-force contribution from Poisson analysis involves a discrete adhesive bacterial cell surface site rather than a single molecular force. The adhesion force arising from these cell surface sites and the number of sites available may differ from strain to strain. Force spectroscopy, however, involves the tedious task of identifying the minor peaks in the AFM retraction force-distance curve. This step can be avoided by carrying out Poisson analysis on the work of adhesion, which can also be derived from retraction force-distance curves. This newly proposed way of performing Poisson analysis confirms that multiple molecular bonds, rather than a single molecular bond, contribute to a discrete adhesive bacterial cell surface site. PMID:21642399

  10. A Hybrid Fuzzy Model for Lean Product Development Performance Measurement

    Science.gov (United States)

    Osezua Aikhuele, Daniel; Mohd Turan, Faiz

    2016-02-01

    In the effort for manufacturing companies to meet up with the emerging consumer demands for mass customized products, many are turning to the application of lean in their product development process, and this is gradually moving from being a competitive advantage to a necessity. However, due to lack of clear understanding of the lean performance measurements, many of these companies are unable to implement and fully integrated the lean principle into their product development process. Extensive literature shows that only few studies have focus systematically on the lean product development performance (LPDP) evaluation. In order to fill this gap, the study therefore proposed a novel hybrid model based on Fuzzy Reasoning Approach (FRA), and the extension of Fuzzy-AHP and Fuzzy-TOPSIS methods for the assessment of the LPDP. Unlike the existing methods, the model considers the importance weight of each of the decision makers (Experts) since the performance criteria/attributes are required to be rated, and these experts have different level of expertise. The rating is done using a new fuzzy Likert rating scale (membership-scale) which is designed such that it can address problems resulting from information lost/distortion due to closed-form scaling and the ordinal nature of the existing Likert scale.

  11. Measurement of D*+ production in charged-current neutrino interactions

    International Nuclear Information System (INIS)

    During the years 1994-1997, the emulsion target of the CHORUS detector was exposed to the wide-band neutrino beam of the CERN SPS of 27 GeV average neutrino energy. In total about 100-bar 000 charged-current neutrino interactions were located in the nuclear emulsion target and fully reconstructed. A high-statistics sample of neutrino interactions with a D0 in the final state was collected. Using the decay mode D*+->D0π+ a production cross-section measurement of the D*+ in neutrino-nucleon charged-current interactions was performed. The low Q-value of the decay was used to isolate a sample of candidate events containing a positive hadron with a small pT with respect to the D0 direction. A signal of 22.1+/-5.5D*+ events was obtained. The D*+ production cross-section relative to the D0 production cross-section, σ(D*+)/σ(D0), was estimated to be 0.38+/-0.09(stat)+/-0.05(syst). From this result, the fraction of D0's produced via the decay of a D* was deduced to be 0.63+/-0.17. The D*+ production cross-section relative to the νμ charged-current interaction, σ(D*+)/σ(CC), was estimated to be [1.02+/-0.25(stat)+/-0.15(syst)]%

  12. Measurement of charm production in antineutrino charged-current interactions

    CERN Document Server

    Onengüt, G; De Jong, M; Konijn, J; Melzer, O; Oldeman, R G C; Pesen, E; Van der Poel, C A F J; Visschers, J L; Güler, M; Köse, U; Serin-Zeyrek, M; Kama, S; Sever, R; Tolun, P; Zeyrek, M T; Catanesi, M G; De Serio, M; Ieva, M; Muciaccia, M T; Radicioni, E; Simone, S; Bülte, A; Winter, Klaus; Van de Vyver, B; Vilain, P; Wilquet, G; Saitta, B; Di Capua, E; Ogawa, S; Shibuya, H; Artamonov, A V; Brunner, J; Chizhov, M; Cussans, D G; Doucet, M; Fabre, Jean-Paul; Hristova, I R; Kawamura, T; Kolev, D; Litmaath, M; Meinhard, H; Panman, J; Papadopoulos, I M; Ricciardi, S; Rozanov, A; Saltzberg, D; Tsenov, R V; Uiterwijk, J W E; Zucchelli, P; Goldberg, J; Chikawa, M; Arik, E; Song, J S; Yoon, C S; Kodama, K; Ushida, N; Aoki, S; Hara, T; Delbar, T; Favart, D; Grégoire, G; Kalinin, S; Makhlyoueva, I V; Gorbunov, P; Khovanskii, V D; Shamanov, V V; Tsukerman, I; Bruski, N; Frekers, D; Rondeshagen, D; Wolff, T; Hoshino, K; Kawada, J; Komatsu, M; Miyanishi, M; Nakamura, M; Nakano, T; Narita, K; Niu, K; Niwa, K; Nonaka, N; Sato, O; Toshito, T; Buontempo, S; Cocco, A G; D'Ambrosio, N; De Lellis, G; De Rosa, G; Di Capua, F; Ereditato, A; Fiorillo, G; Marotta, A; Messina, M; Migliozzi, P; Pistillo, C; Santorelli, R; Scotto-Lavina, L; Strolin, P; Tioukov, V; Nakamura, K; Okusawa, T; Dore, U; FLoverre, P; Ludovici, L; Maslennikov, A L; Righini, P; Rosa, G; Santacesaria, R; Satta, A; Spada, F R; Barbuto, E; Bozza, C; Grella, G; Romano, G; Sirignano, C; Sorrentino, S; Sato, Y; Tezuka, I

    2004-01-01

    During the years 1994-97, the emulsion target of the CHORUS detector was exposed to the wideband neutrino beam of the CERN SPS collecting about 10^6 neutrino interactions. A measurement of nubar_mu-induced charm production is performed by usingthe presence of a 5% nubarmu component in the nu_mu beam. The measurement takes advantage of the capability to observe the decay topology in the emulsion. The analysis is based on a sample of charged-current interactions with at least one identified muon. About 100 000 vere located in the emulsion target and fully reconstructed. By requiring a positive muon charge as determined by the CHORUS spectrometer, 32-nubar_mu induced charm events were observed with an estimated background of 3.2 events. At an average antineutrino energy in the neutrino beam of 18GeV, the charm production rate induced by anitneutrinos is measured to be sigma(nubar_muN -> mu+cbarX)/sigma(nubar_muN -> mu+X) = (5.0^+1.4_-0.9(stat) +- 0.7(syst))%. The ratio between neutral and charged charm productio...

  13. Measurement of β-Glucan in Mushrooms and Mycelial Products.

    Science.gov (United States)

    McCleary, Barry V; Draga, Anna

    2016-01-01

    A robust and reliable method has been developed for the measurement of β-glucan in mushroom and mycelial products. Total glucan (plus free glucose and glucose from sucrose) was measured using controlled acid hydrolysis with H2SO4 and the glucose released specifically was measured using glucose oxidase/peroxidase reagent. α-Glucan (starch/glycogen) plus free glucose and glucose from sucrose were specifically measured after hydrolysis of starch/glycogen to glucose with glucoamylase and sucrose to glucose plus fructose with invertase and the glucose specifically measured with GOPOD reagent. β-Glucan was determined by the difference. Several acid and enzyme-based methods for the hydrolysis of the β-glucan were compared, and the best option was the method using H2SO4. For most samples, similar β-glucan values were obtained with both the optimized HCl and H2SO4 PROCEDURES: However, in the case of certain samples, specifically Ganoderma lucidum and Poria cocus, the H2SO4 procedure resulted in significantly higher values. Hydrolysis with 2 N trifluoroacetic acid at 120°C was found to be much less effective than either of the other two acids evaluated. Assays based totally on enzymatic hydrolysis, in general, yielded much lower values than those obtained with the H2SO4 procedure. PMID:26957216

  14. Microbiology and biogeochemistry of sediments and rhizosphere of mangroves: bacterial production, sulphate-reduction and methylation of mercury with methodological focus on incubation-extraction of 14C-leucine

    International Nuclear Information System (INIS)

    Mangroves are one of the most important ecosystems when it comes to cycling of various elements, including carbon and mercury. Microbiological processes that occur in sediment are essential for carbon mineralization, its conversion into biomass and for availability of mercury to the food chain. Sulfate-reducing bacteria are one of the main groups responsible for degradation of organic compounds in marine sediments and mercury methylation, especially in the rhizosphere of macrophyte. The aim of this study was to evaluate bacterial production (BP) over different sedimentary profiles as well as mercury methylation (% MeHg), sulfate reduction rates (SRR) and bacterial production in the rhizosphere of a ubiquitous mangrove tree. Radiochemical approaches were used to access bacterial production (14C-leucine), sulfate reduction (35SO4) and mercury methylation (203Hg). Study area was located at Coroa Grande (Sepetiba bay) and Jequia mangrove (Guanabara bay). Methodological studies using 14C-leucine as a tool to assess bacterial production in mangrove sediment were not found. In this context, we tested two leucine uptake methodologies for measuring bacterial production in mangrove sediments according to Baath et al. (2001) Soil Biol. Biochem., v.33,p. 1571-1574 and Fischer and Pusch (1999) Appl. Environ. Microbiol., v.6, p.4411-4418. Our results suggest that an adaptation of both techniques were suitable to measure BP in mangrove sediment. We also provided underlying parameters of the method such as saturation level and linearity of leucine incorporation that can be used as guidance for future studies in mangrove. Once the methodology was established, we accessed BP along a shallow sedimentary profile in three physiographic mangroves types: basin, fringe and riverine. BP was highly heterogeneous in different physiographic types of mangroves and along the sediment profiles.The mangrove located at Guanabara bay presented BP which was 50 times higher than tho one located at

  15. Responses of soil microbial biomass and bacterial community structure to closed-off management (an ecological natural restoration measures): A case study of Dongting Lake wetland, middle China.

    Science.gov (United States)

    Dai, Juan; Wu, Haipeng; Zhang, Chang; Zeng, Guangming; Liang, Jie; Guo, Shenglian; Li, Xiaodong; Huang, Lu; Lu, Lunhui; Yuan, Yujie

    2016-09-01

    Soil microbial biomass (SMB) and bacterial community structure, which are critical to global ecosystem and fundamental ecological processes, are sensitive to anthropogenic activities and environmental conditions. In this study, we examined the possible effects of closed-off management (an ecological natural restoration measures, ban on anthropogenic activity, widely employed for many important wetlands) on SMB, soil bacterial community structure and functional marker genes of nitrogen cycling in Dongting Lake wetland. Soil samples were collected from management area (MA) and contrast area (CA: human activities, such as hunting, fishing and draining, are permitted) in November 2013 and April 2014. Soil properties, microbial biomass carbon (MBC), and bacterial community structure were investigated. Comparison of the values of MA and CA showed that SMB and bacterial community diversity of the MA had a significant increase after 7 years closed-off management. The mean value of Shannon-Weiner diversity index of MA and CA respectively were 2.85 and 2.07. The gene copy numbers of 16S rRNA and nosZ of MA were significant higher than those of CA. the gene copy numbers of ammonia-oxidizing archaea (AOA) and nirK of MA were significant lower than those of CA. However, there was no significant change in the gene copy numbers of ammonia-oxidizing bacteria (AOB) and nirS.

  16. Responses of soil microbial biomass and bacterial community structure to closed-off management (an ecological natural restoration measures): A case study of Dongting Lake wetland, middle China.

    Science.gov (United States)

    Dai, Juan; Wu, Haipeng; Zhang, Chang; Zeng, Guangming; Liang, Jie; Guo, Shenglian; Li, Xiaodong; Huang, Lu; Lu, Lunhui; Yuan, Yujie

    2016-09-01

    Soil microbial biomass (SMB) and bacterial community structure, which are critical to global ecosystem and fundamental ecological processes, are sensitive to anthropogenic activities and environmental conditions. In this study, we examined the possible effects of closed-off management (an ecological natural restoration measures, ban on anthropogenic activity, widely employed for many important wetlands) on SMB, soil bacterial community structure and functional marker genes of nitrogen cycling in Dongting Lake wetland. Soil samples were collected from management area (MA) and contrast area (CA: human activities, such as hunting, fishing and draining, are permitted) in November 2013 and April 2014. Soil properties, microbial biomass carbon (MBC), and bacterial community structure were investigated. Comparison of the values of MA and CA showed that SMB and bacterial community diversity of the MA had a significant increase after 7 years closed-off management. The mean value of Shannon-Weiner diversity index of MA and CA respectively were 2.85 and 2.07. The gene copy numbers of 16S rRNA and nosZ of MA were significant higher than those of CA. the gene copy numbers of ammonia-oxidizing archaea (AOA) and nirK of MA were significant lower than those of CA. However, there was no significant change in the gene copy numbers of ammonia-oxidizing bacteria (AOB) and nirS. PMID:27036597

  17. Measurements of e+e- pair production at the Bevalac

    International Nuclear Information System (INIS)

    A complete kinematic description of a lepton pair requires 6 independent variables, in contrast to the case of a real photon, where there are only 3 independent variables. The mass and momentum of the virtual photon may be specified independently, with the remaining variables being the two angles specifying its production direction, and the two angles of the decay in its rest frame. It has become customary to use as kinetics variables: the mass, M; the transverse momentum, Pt; and a longitudinal variable, either the rapidity -- Y, or the scaling variable -- X. Data are almost always presented as a function of only one of these variables. This may be due to the difficulty inherent in presenting multi-dimensional data, to poor statistics, to limited experimental acceptance, or to some combination of these reasons. It should be noted, however, that these one-dimensional projections always represent integrations over the remaining variables -- integrations within which the shape and limits of the acceptance of the experimental apparatus must be taken into account. The effects of the acceptance must be understood in comparing experimental data either to theory or to results from experiments with different coverage of the total phase space. Although we have a strong interest in studying nucleus-nucleus collisions using the tool, most of the discussion presented here will be about our measurements in p+Be collisions. It was necessary for us to make these measurements because, in the relevant range of incident energies, the yield of electron pairs from nucleon-nucleon collisions had not been measured, nor was the hadronic production mechanism understood. A brief discussion of lepton production in hadronic collision will help put out our results in a proper framework. 15 refs., 9 figs., 2 tabs

  18. Measuring NO Production by Plant Tissues and Suspension Cultured Cells

    Institute of Scientific and Technical Information of China (English)

    Jan Vitecek; Vilem Reinohl; Russell L.Jones

    2008-01-01

    We describe an inexpensive and reliable detector for measuring NO emitted in the gas phase from plants.The method relies on the use of a strong oxidizer to convert NO to NO2 and subsequent capture of NO2 by a Griess reagent trap.The set-up approaches the sensitivity for NO comparable to that of instruments based on chemiluminescence and photoacoustic detectors.We demonstrate the utility of our set-up by measuring NO produced by a variety of well established plant sources.NO produced by nitrate reductase (NR) in tobacco leaves and barley aleurone was readily detected,as was the production of NO from nitrite by the incubation medium of barley aleurone.Arabidopsis mutants that overproduce NO or lack NO-synthase (AtNOS1) also displayed the expected NO synthesis phenotype when assayed by our set-up.We could also measure NO production from elicitor-treated suspension cultured cells using this set-up.Further,we have focused on the detection of NO by a widely used fluorescent probe 4-amino-5-methylamino-2',7'-difluorofluorescein (DAF-FM).Our work points to the pitfalls that must be avoided when using DAF-FM to detect the production of NO by plant tissues.In addition to the dramatic effects that pH can have on fluorescence from DAF-FM,the widely used NO scavengers 2-phenyl-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide (PTIO) and 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) can produce anomalous and unexpected results.Perhaps the most serious drawback of DAF-FM is its ability to bind to dead cells and remain NO-sensitive.

  19. Prevalence of tabacco product use in Latvia and control measures

    Directory of Open Access Journals (Sweden)

    Kokarevica A.

    2012-10-01

    Full Text Available The use of tobacco products is a major problem having a serious effect on public health. Deaths from external causes are those that can be prevented by ensuring environmental safety and educating the society about the effect of lifestyle habits and behaviour on health of an individual. Not only research data reveal the prevalence of tobacco use but also the rate of tobacco sales. Tobacco industry marketing includes advertising, sales promotion and sponsorship strategies that are aimed at promotion of tobacco use. Demand for tobacco products is influenced also by changes in legislation relating to ban on tobacco advertising and sponsorship. Therefore it is necessary to introduce an agreed strategy for reducing tobacco use. The countries that have ratified the World Health Organisation (WHO Framework Convention on Tobacco Control (the Convention should develop and implement an effective tobacco control programme. In Latvia the number of daily smokers gradually decreases thanks to the extensive smoking restrictions though tobacco manufacturers use all the available media, radio and television, newspapers, magazines, advertisements and Internet, to advertise their products. Therefore in order to combat the prevalence of smoking first of all it is necessary to limit cigarette marketing and sales and to carry out monitoring and development of tobacco control measures on the state level. The sales of legal cigarettes have decreased in Latvia starting from 2009. However, the increase in tax rates and prices has contributed to the movement of illegal goods therefore it is necessary to take additional restrictive measures concerning the movement of illegal goods. Though amendments to legislation of Latvia relating to tobacco control comply with the requirements of the WHO Convention it is necessary to evaluate the efficiency of control measures and to improve them. Systematic and comprehensive education of the public is required to encourage the change of

  20. Measurement and characterization of fission products released from LWR fuel

    International Nuclear Information System (INIS)

    Samples of commercial LWR fuel have been heated under simulated accident conditions to determine the extent and the chemical forms of fission product release. Of the five tests discussed, the fractional releases of Kr, I, and Cs varied from proportional 2% at 14000C to >50% at 20000C; much smaller fractions of Ru, Ag, Sb, and Te were measured in some tests. The major chemical forms in the effluent appeared to include CsI, CsOH, Sb, Te, and Ag. (orig./HP)

  1. Charm and Bottom Production Measurements at the LHC

    CERN Document Server

    Walkowiak, W

    2008-01-01

    Early data of the ATLAS and CMS experiments at the LHC will allow us to measure the cross sections for beauty and heavy quarkonia production in proton-proton collisions at a center-of-mass energy of 14 TeV to a reasonable precision. Different experimental approaches employing single or di-muon triggered events and b-tagging methods are discussed. The potential for extracting the polarization of vector states from the decays J/psi to mu+mu- and Y to mu+mu- is presented.

  2. Charm and Bottom Production Measurements at the LHC

    CERN Document Server

    Walkowiak, Wolfgang

    2008-01-01

    Early data of the ATLAS and CMS experiments at the LHC will allow us to measure the cross sections for beauty and heavy quarkonia production in proton-proton collisions at a center-of-mass energy of 14 TeV to a reasonable precision. Different experimental approaches employing single or di-muon triggered events and b-tagging methods are discussed. The potential for extracting the polarization of vector states from the decays J/psi to mu+ mu- and Y to mu+ mu- is presented.

  3. Control strategies against Campylobacter at the poultry production level: biosecurity measures, feed additives and vaccination.

    Science.gov (United States)

    Meunier, M; Guyard-Nicodème, M; Dory, D; Chemaly, M

    2016-05-01

    Campylobacteriosis is the most prevalent bacterial foodborne gastroenteritis affecting humans in the European Union, and ranks second in the United States only behind salmonellosis. In Europe, there are about nine million cases of campylobacteriosis every year, making the disease a major public health issue. Human cases are mainly caused by the zoonotic pathogen Campylobacter jejuni. The main source of contamination is handling or consumption of poultry meat. Poultry constitutes the main reservoir of Campylobacter, substantial quantities of which are found in the intestines following rapid, intense colonization. Reducing Campylobacter levels in the poultry chain would decrease the incidence of human campylobacteriosis. As primary production is a crucial step in Campylobacter poultry contamination, controlling the infection at this level could impact the following links along the food chain (slaughter, retail and consumption). This review describes the control strategies implemented during the past few decades in primary poultry production, including the most recent studies. In fact, the implementation of biosecurity and hygiene measures is described, as well as the immune strategy with passive immunization and vaccination trials and the nutritional strategy with the administration of organic and fatty acids, essential oil and plant-derived compound, probiotics, bacteriocins and bacteriophages. PMID:26541243

  4. Measurement of AFB in B± meson production at D0

    Science.gov (United States)

    Hoganon, J.; D0 Collaboration

    2016-07-01

    We present a measurement of the forward-backward asymmetry in the production of B± mesons, AFB( B±) , using B± → J/ ψ K± decays in 10.4 fb-1 of p bar{{p}} collisions at √{{s}} = 1.96 TeV collected by the D0 experiment during Run II of the Tevatron collider. A nonzero asymmetry would indicate a preference for a particular flavor, i.e., b quark or bar{{b}} antiquark, to be produced in the direction of the proton beam. We extract AFB( B±) from a maximum-likelihood fit to the difference between the numbers of forward- and backward-produced B± mesons. We measure an asymmetry consistent with zero: AFB( B±) = [- 0.24±0.41(stat)±0.19(syst)]%.

  5. Nanomaterial-based sensors for detection of foodborne bacterial pathogens and toxins as well as pork adulteration in meat products

    OpenAIRE

    Stephen Inbaraj, B; Chen, B H

    2016-01-01

    Food safety draws considerable attention in the modern pace of the world owing to rapid-changing food recipes and food habits. Foodborne illnesses associated with pathogens, toxins, and other contaminants pose serious threat to human health. Besides, a large amount of money is spent on both analyses and control measures, which causes significant loss to the food industry. Conventional detection methods for bacterial pathogens and toxins are time consuming and laborious, requiring certain soph...

  6. New challenge in the speciation of selenium. Measurement and production on nano selenium

    International Nuclear Information System (INIS)

    Complete text of publication follows. We have found that several species of probiotic bacteria also used in food industry for making yogurts is capable of producing spherical elemental selenium nanospheres having an average diameter in the range of 50-500 nm when 1-1000 mg/L selenium was added to the medium in the form of selenite ions. Elemental selenium produced thereby has a high degree of purity, is spherical, and its size and crystalline form depends on the bacterium species applied. We have found that some species of the probiotic yogurt bacteria (e.g. Bifidobacterium bifidum or Bifidobacterium longum) are capable of producing the grey crystalline form of elemental selenium which is so far unprecedented in the art for any bacteria capable of producing elemental selenium nanoparticles. Our finding, therefore, enables the first time the development of economical industrial bacterial fermentation based processes for the production of a high quality elemental selenium material comprising uniformly sized grey or red nanospheres having an average diameter in the range of 50-500 nm. The size and the crystalline form of the produced nanosized (50-500 nm) spherical particles is defined by the selected microorganism. This genetic pre-determination result in reproducible production of a material having individual characteristics which can be used in numerous fields of industry and research. The produced nano selenium could be a good raw material for a production of certified reference materials. The measurement of the produced elemental nanoselenium is a new challenge for the speciation analysis. A sample preparation and measurement method was developed and investigated for the analysis of different selenium forms by HPLC-AFS system. The atomic fluorescence (AFS) was a reliable and simple detection method for the elemental nano selenium. The elemental selenium can produce hydride in the system or can be converted to selenite with HCl/H2O2 digestion.

  7. Statistical optimization of medium composition for bacterial cellulose production by Gluconacetobacter hansenii UAC09 using coffee cherry husk extract--an agro-industry waste.

    Science.gov (United States)

    Rani, Mahadevaswamy Usha; Rastogi, Navin K; Appaiah, K A Anu

    2011-07-01

    During the production of grape wine, the formation of thick leathery pellicle/bacterial cellulose (BC) at the airliquid interface was due to the bacterium, which was isolated and identified as Gluconacetobacter hansenii UAC09. Cultural conditions for bacterial cellulose production from G. hansenii UAC09 were optimized by central composite rotatable experimental design. To economize the BC production, coffee cherry husk (CCH) extract and corn steep liquor (CSL) were used as less expensive sources of carbon and nitrogen, respectively. CCH and CSL are byproducts from the coffee processing and starch processing industry, respectively. The interactions between pH (4.5- 8.5), CSL (2-10%), alcohol (0.5-2%), acetic acid (0.5- 2%), and water dilution rate to CCH ratio (1:1 to 1:5) were studied using response surface methodology. The optimum conditions for maximum BC production were pH (6.64), CSL (10%), alcohol (0.5%), acetic acid (1.13%), and water to CCH ratio (1:1). After 2 weeks of fermentation, the amount of BC produced was 6.24 g/l. This yield was comparable to the predicted value of 6.09 g/l. This is the first report on the optimization of the fermentation medium by RSM using CCH extract as the carbon source for BC production by G. hansenii UAC09.

  8. An Inner Membrane Protein (Imp) of Xanthomonas oryzae pv. oryzicola Functions in Carbon Acquisition, EPS Production, Bacterial Motility and Virulence in Rice

    Institute of Scientific and Technical Information of China (English)

    CHEN Gong-you

    2014-01-01

    Xanthomonas oryzae pv. oryzicola (Xoc) causes bacterial leaf streak, a devastating disease in rice-growing regions worldwide. A Tn5-insertion mutant in Xoc_3248, encoding an inner membrane protein (Imp), showed reduced virulence in rice. To explore the potential function of this gene in virulence, a deletion mutant R∆imp was constructed in the wild-type RS105. The R∆imp mutant was signiifcantly impaired for bacterial virulence and growth in planta. The mutation in imp made the pathogen insufifciently utilize glucose, fructose, mannose or pyruvate as a sole carbon source, leading to less extracellular polysaccharide (EPS) production and reduced motility. The deifciencies noted for the mutant were restored to wild-type levels when imp was introduced in trans. Transcription of imp was signiifcantly declined when hrpG and hrpX was mutated and the expression of hrpG and hrpX was also signiifcantly declined when imp was deleted. Cell sublocalization in planta showed Imp membrane-binding feature. These results suggest that Imp is a virulence factor with roles in the catabolism of sugars, EPS production, and bacterial motility.

  9. Impact of the freeze-drying process on product appearance, residual moisture content, viability, and batch uniformity of freeze-dried bacterial cultures safeguarded at culture collections.

    Science.gov (United States)

    Peiren, Jindrich; Hellemans, Ann; De Vos, Paul

    2016-07-01

    In this study, causes of collapsed bacterial cultures in glass ampoules observed after freeze-drying were investigated as well as the influence of collapse on residual moisture content (RMC) and viability. Also, the effect of heat radiation and post freeze-drying treatments on the RMC was studied. Cake morphologies of 21 bacterial strains obtained after freeze-drying with one standard protocol could be classified visually into four major types: no collapse, porous, partial collapse, and collapse. The more pronounced the collapse, the higher residual moisture content of the freeze-dried product, ranging from 1.53 % for non-collapsed products to 3.62 % for collapsed products. The most important cause of collapse was the mass of the inserted cotton plug in the ampoule. Default cotton plugs with a mass between 21 and 30 mg inside the ampoule did not affect the viability of freeze-dried Aliivibrio fischeri LMG 4414(T) compared to ampoules without cotton plugs. Cotton plugs with a mass higher than 65 mg inside the ampoule induced a full collapsed product with rubbery look (melt-back) and decreasing viability during storage. Heat radiation effects in the freeze-drying chamber and post freeze-drying treatments such as exposure time to air after freeze-drying and manifold drying time prior to heat sealing of ampoules influenced the RMC of freeze-dried products. To produce uniform batches of freeze-dried bacterial strains with intact cake structures and highest viabilities, inserted cotton plugs should not exceed 21 mg per ampoule. Furthermore, heat radiation effects should be calculated in the design of the primary drying phase and manifold drying time before heat sealing should be determined as a function of exposure time to air.

  10. Measurement of charm production in neutrino charged-current interactions

    International Nuclear Information System (INIS)

    The nuclear emulsion target of the CHORUS detector was exposed to the wide-band neutrino beam of the CERN SPS of 27 GeV average neutrino energy from 1994 to 1997. In total, about 100 000 charged-current (CC) neutrino interactions with at least one identified muon were located in the emulsion target and fully reconstructed, using newly developed automated scanning systems. Charmed particles were searched for by a program recognizing particle decays. The observation of the decay in nuclear emulsion makes it possible to select a sample with very low background and minimal kinematical bias. In all, 2013 CC interactions with a charmed hadron candidate in the final state were selected and confirmed through visual inspection. The charm production rate induced by neutrinos relative to the CC cross-section is measured to be σ(νμN→μ-CX)/σ(CC)=(5.75 ± 0.32(stat)±0.30(syst))%. The charm production cross-section as a function of neutrino energy is also obtained. The results are in good agreement with previous measurements. The charm-quark hadronization produces the following charmed hadrons with relative fractions (in %): fD0=43.7±4.5, fΛc+=19.2±4.2, fD+=25.3±4.2 and fDs+=11.8±4.7.

  11. Measurement of CP asymmetries in neutralino production at the ILC

    CERN Document Server

    Kittel, O; Rolbiecki, K; Schade, P; Terwort, M

    2012-01-01

    We study the prospects to measure the CP-sensitive triple-product asymmetries in neutralino production e+e- -> ~chi^0_i ~chi^0_1 and subsequent leptonic two-body decays ~chi^0_i -> ~l_R l, ~l_R -> ~chi^0_1 l, for l=e, mu, within the Minimal Supersymmetric Standard Model. We include a full detector simulation of the International Large Detector for the International Linear Collider. The simulation was performed at a center of mass energy of sqrt{s}=500 GeV, including the relevant Standard Model background processes, a realistic beam energy spectrum, beam backgrounds and a beam polarization of 80% and -60% for the electron and positron beams, respectively. In order to effectively disentangle different signal samples and reduce SM and SUSY backgrounds we apply a method of kinematic reconstruction. Assuming an integrated luminosity of 500 fb^-1 collected by the experiment and the performance of the current ILD detector, we arrive at a relative measurement accuracy of 10% for the CP-sensitive asymmetry in our scen...

  12. Measurement of CP asymmetries in neutralino production at the ILC

    Energy Technology Data Exchange (ETDEWEB)

    Kittel, O. [Granada Univ. (Spain). Dept. de Fisica Teorica y del Cosmos y CAFPE; Moortgat-Pick, G. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Rolbiecki, K.; Terwort, M. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Schade, P. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); European Organization for Nuclear Research (CERN), Geneva (Switzerland)

    2011-08-15

    We study the prospects to measure the CP-sensitive triple-product asymmetries in neutralino production e{sup +}e{sup -} {yields} {chi}{sup 0}{sub i}{chi}{sup 0}{sub 1} and subsequent leptonic twobody decays {chi}{sup 0}{sub i} {yields} l{sub R}l, l{sub R} {yields} {chi}{sup 0}{sub 1}l for l=e,{mu} within the Minimal Supersymmetric Standard Model. We include a full detector simulation of the International Large Detector for the International Linear Collider. The simulation was performed at a center of mass energy of {radical}(s)=500 GeV, including the relevant Standard Model background processes, a realistic beam energy spectrum, beam backgrounds and a beam polarization of 80% and -60% for the electron and positron beams, respectively. In order to effectively disentangle different signal samples and reduce SM and SUSY backgrounds we apply a method of kinematic reconstruction. Assuming an integrated luminosity of 500 fb{sup -1} collected by the experiment and the performance of the current ILD detector, we arrive at a relative measurement accuracy of 10% for the CP-sensitive asymmetry in our scenario. (orig.)

  13. Measurement of Fission Product Yields from Fast-Neutron Fission

    Science.gov (United States)

    Arnold, C. W.; Bond, E. M.; Bredeweg, T. A.; Fowler, M. M.; Moody, W. A.; Rusev, G.; Vieira, D. J.; Wilhelmy, J. B.; Becker, J. A.; Henderson, R.; Kenneally, J.; Macri, R.; McNabb, D.; Ryan, C.; Sheets, S.; Stoyer, M. A.; Tonchev, A. P.; Bhatia, C.; Bhike, M.; Fallin, B.; Gooden, M. E.; Howell, C. R.; Kelley, J. H.; Tornow, W.

    2014-09-01

    One of the aims of the Stockpile Stewardship Program is a reduction of the uncertainties on fission data used for analyzing nuclear test data [1,2]. Fission products such as 147Nd are convenient for determining fission yields because of their relatively high yield per fission (about 2%) and long half-life (10.98 days). A scientific program for measuring fission product yields from 235U,238U and 239Pu targets as a function of bombarding neutron energy (0.1 to 15 MeV) is currently underway using monoenergetic neutron beams produced at the 10 MV Tandem Accelerator at TUNL. Dual-fission chambers are used to determine the rate of fission in targets during activation. Activated targets are counted in highly shielded HPGe detectors over a period of several weeks to identify decaying fission products. To date, data have been collected at neutron bombarding energies 4.6, 9.0, 14.5 and 14.8 MeV. Experimental methods and data reduction techniques are discussed, and some preliminary results are presented.

  14. Measurement of $D^{*+}$ production in charged-current neutrino interactions

    CERN Document Server

    Önengüt, G; De Jong, M; Oldeman, R G C; Güler, M; Köse, U; Tolun, P; Catanesi, M G; Muciaccia, M T; Winter, Klaus; Van de Vyver, B; Vilain, P; Wilquet, G; Saitta, B; Di Capua, E; Ogawa, S; Shibuya, H; Goldberg, J; Hristova, I R; Kawamura, T; Kolev, D; Kayis-Topaksu, A; Meinhard, H; Panman, J; Rozanov, A; Tsenov, R V; Zucchelli, P; Uiterwijk, J W E; Chikawa, M; Song, J S; Yoon, C S; Kodama, K; Ushida, N; Hara, T; Aoki, S; Delbar, T; Favart, D; Grégoire, G; Kalinin, S; Makhlyoueva, I V; Bruski, N; Frekers, D; Tsukerman, I; Shamanov, V V; Khovanskii, V D; Gorbunov, P; Artamonov, A V; Sato, Y; Tezuka, I; Barbuto, E; Bozza, C; Grella, G; Romano, G; Sirignano, C; Sorrentino, S; Dore, U; Loverre, P F; Ludovici, L; Rosa, G; Santacesaria, R; Satta, A; Spada, F R; Okusawa, T; Hoshino, K; Kawada, J; Komatsu, M; Miyanishi, M; Nakamura, M; Nakano, T; Narita, K; Niu, K; Niwa, K; Nonaka, N; Sato, O; Toshito, T; Buontempo, S; Cocco, A G; D'Ambrosio, N; De Lellis, G; De Rosa, G; Di Capua, F; Fiorillo, G; Marotta, A; Messina, M; Migliozzi, P; Scotto-Lavina, L; Strolin, P; Tioukov, V

    2005-01-01

    During the years 1994-97, the emulsion target of the CHORUS detector was exposed to the wide-band neutrino beam of the CERN SPS of 27 GeV average neutrino energy. In total about 100 000 charged-current neutrino interactions were located in the nuclear emulsion target and fully reconstructed. A high-statistics sample of neutrino interactions with a D^0 in the final state was collected. Using the decay mode D*^+ -> D ^0 \\pi+ a production cross-section measurement of the D*^+ in neutrino-nucleon charged-current interactions was performed. The low Q-value of the decay was used to isolate a sample of candidate events containing a positive hadron with a small p_T with respect to the D^0 direction. A signal of 22.1 +- 5.5 D*^+ events was obtained. The D*^+ production cross-section relative to the D^0 production cross-section, \\sigma(D*^+) / \\sigma(D^0), was estimated to be 0.38 +- 0.09(stat) +- 0.05(syst). From this result, the fraction of D^0’s produced via the decay of a D* was deduced to be 0.63 +- 0.17. The D*...

  15. A hybrid DNA extraction method for the qualitative and quantitative assessment of bacterial communities from poultry production samples

    Science.gov (United States)

    The efficacy of DNA extraction protocols can be highly dependent upon both the type of sample being investigated and the types of downstream analyses performed. Considering that the use of new bacterial community analysis techniques (e.g., microbiomics, metagenomics) is becoming more prevalent in th...

  16. What Will SWOT Measurements and Products Look Like?

    Science.gov (United States)

    Alsdorf, D.; Bates, P.; Lettenmaier, D.; Mognard, N.; Moller, D.; Rodriguez, E.; Participants, S.

    2008-12-01

    The Surface Water Ocean Topography (SWOT) satellite mission is designed to measure water elevations across the world's rivers, lakes, wetlands, and oceans. The mission is designed to provide global, high- spatial resolution, ~weekly products of river discharge and changes in stored water volumes. Already, some satellite missions such as GRACE, various altimeters, SRTM, and imaging systems, provide a glimpse of what these products might look like. For example, despite GRACE's hundreds of kilometers of spatial resolution, it allows a first-order assessment of Amazon floodplain storage anomalies - measurements that are key for understanding the hydraulic flux and subsequent delivery of sediment and exchange of nutrients. Various altimeters have shown that spot elevations of water surfaces are possible, albeit without a fine resolution on the order of less than 100m. In contrast, repeat-pass interferometric SAR measurements show a high-spatial resolution (~30m) but poor temporal resolution (~monthly) and are restricted to dh/dt mappings (i.e., water elevation changes with time). SRTM is perhaps the most spatially detailed mapping of water surface elevations globally, but is restricted to one temporal map (i.e., February 2000). SWOT is designed to overcome these various limitations by using a Ka-band radar interferometer which is essentially a higher- accuracy and more compact version of SRTM. Its look angle is near-nadir which maximizes the returned radar energy and improves the height accuracy to +/- 0.5m (an order of magnitude better than SRTM). Because SWOT uses this two-antennae SAR system, the smallest spatial resolution theoretically possible is 2m (in azimuth) by 0.75m (in range) whereas, after multi-looking, SWOT will have a nominal resolution of around 30m x 30m. The mission will produce terabytes of data per month, thus ground systems need to be designed to rapidly convert water elevation measurements to products of discharge and storage change. SWOT is in

  17. Measurements of charged fusion product diffusion in TFTR

    International Nuclear Information System (INIS)

    The single particle confinement of charged fusion products, namely the 1 MeV triton and the 3 MeV proton, has been studied using a detector located near the outer midplane of TFTR. The detector, which measure the flux of escaping particles, is composed of a scintillator [ZnS(Ag)] and a system of collimating apertures, which permit pitch angle, energy and time resolution. It is mounted on a movable probe which can be inserted 25 cm into the vacuum vessel. Measurements indicate a level of losses higher than expected from a first-orbit loss mechanism alone. The primary candidate for explaining the observed anomalous losses is the toroidal field (TF) stochastic ripple diffusion, theoretically discovered by Goldston, White and Boozer. This loss mechanism is expected to be localized near the outer midplane where, at least at high current (approx-gt 1.0 MA) it would locally dominate over first-orbit losses. Calculations made with a mapping particle orbit code (MAPLOS) show a semi-quantitative agreement with the measurements. The predominant uncertainties in the numerical simulations were found to originate from the modeling of the first wall geometry and also from the assumed plasma current and source profiles. Direct measurements of the diffusion rate were performed by shadowing the detector with a second movable probe used as an obstacle. The diffusion rate was also measured by moving the detector behind the radius of the RF limiters, located on the outer wall. Comparisons of these experimental results with numerical simulations, which include diffusive mechanisms, indicate a quantitative agreement with the TF stochastic ripple diffusion model

  18. Measurements of charged fusion product diffusion in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Boivin, R.L.

    1991-12-01

    The single particle confinement of charged fusion products, namely the 1 MeV triton and the 3 MeV proton, has been studied using a detector located near the outer midplane of TFTR. The detector, which measure the flux of escaping particles, is composed of a scintillator (ZnS(Ag)) and a system of collimating apertures, which permit pitch angle, energy and time resolution. It is mounted on a movable probe which can be inserted 25 cm into the vacuum vessel. Measurements indicate a level of losses higher than expected from a first-orbit loss mechanism alone. The primary candidate for explaining the observed anomalous losses is the toroidal field (TF) stochastic ripple diffusion, theoretically discovered by Goldston, White and Boozer. This loss mechanism is expected to be localized near the outer midplane where, at least at high current ({approx gt} 1.0 MA) it would locally dominate over first-orbit losses. Calculations made with a mapping particle orbit code (MAPLOS) show a semi-quantitative agreement with the measurements. The predominant uncertainties in the numerical simulations were found to originate from the modeling of the first wall geometry and also from the assumed plasma current and source profiles. Direct measurements of the diffusion rate were performed by shadowing the detector with a second movable probe used as an obstacle. The diffusion rate was also measured by moving the detector behind the radius of the RF limiters, located on the outer wall. Comparisons of these experimental results with numerical simulations, which include diffusive mechanisms, indicate a quantitative agreement with the TF stochastic ripple diffusion model.

  19. Measurements of charged fusion product diffusion in TFTR

    Energy Technology Data Exchange (ETDEWEB)

    Boivin, R.L.

    1991-12-01

    The single particle confinement of charged fusion products, namely the 1 MeV triton and the 3 MeV proton, has been studied using a detector located near the outer midplane of TFTR. The detector, which measure the flux of escaping particles, is composed of a scintillator [ZnS(Ag)] and a system of collimating apertures, which permit pitch angle, energy and time resolution. It is mounted on a movable probe which can be inserted 25 cm into the vacuum vessel. Measurements indicate a level of losses higher than expected from a first-orbit loss mechanism alone. The primary candidate for explaining the observed anomalous losses is the toroidal field (TF) stochastic ripple diffusion, theoretically discovered by Goldston, White and Boozer. This loss mechanism is expected to be localized near the outer midplane where, at least at high current ({approx_gt} 1.0 MA) it would locally dominate over first-orbit losses. Calculations made with a mapping particle orbit code (MAPLOS) show a semi-quantitative agreement with the measurements. The predominant uncertainties in the numerical simulations were found to originate from the modeling of the first wall geometry and also from the assumed plasma current and source profiles. Direct measurements of the diffusion rate were performed by shadowing the detector with a second movable probe used as an obstacle. The diffusion rate was also measured by moving the detector behind the radius of the RF limiters, located on the outer wall. Comparisons of these experimental results with numerical simulations, which include diffusive mechanisms, indicate a quantitative agreement with the TF stochastic ripple diffusion model.

  20. Productive measures: Culture and measurement in the context of everyday neoliberalism

    Directory of Open Access Journals (Sweden)

    David Beer

    2015-04-01

    Full Text Available This article reflects on how data circulations and data analysis have become a central and routine part of contemporary life; it does this through the lens of a particular cultural form: the game of football. More specifically, the article focuses upon the role of data in the production and playing of football, with the suggestion that forms of measurement and pattern recognition are now central to the performance of footballers and the recruitment and organization of squads. The article reflects on what this case study reveals about the implications of data, metrics and analytics for contemporary culture and suggests that we can use examples like football to see how embedded these data-processes are in the social world. This article presents the concept of productive measures as one means for analysing such developments.

  1. Fermentative hydrogen production and bacterial community structure in high-rate anaerobic bioreactors containing silicone-immobilized and self-flocculated sludge.

    Science.gov (United States)

    Wu, Shu-Yii; Hung, Chun-Hsiung; Lin, Chi-Neng; Chen, Hsin-Wei; Lee, An-Sheng; Chang, Jo-Shu

    2006-04-01

    A novel continuously stirred anaerobic bioreactor (CSABR) seeded with silicone-immobilized sludge was developed for high-rate fermentative H2 production using sucrose as the limiting substrate. The CSABR system was operated at a hydraulic retention time (HRT) of 0.5-6 h and an influent sucrose concentration of 10-40 g COD/L. With a high feeding sucrose concentration (i.e., 30-40 g COD/L) and a short HRT (0.5 h), the CSABR reactor produced H2 more efficiently with the highest volumetric rate (VH2) of 15 L/h/L (i.e., 14.7 mol/d/L) and an optimal yield of ca. 3.5 mol H2/mol sucrose. The maximum VH2 value obtained from this work is much higher than any other VH2 values ever documented. Formation of self-flocculated granular sludge occurred during operation at a short HRT. The granule formation is thought to play a pivotal role in the dramatic enhancement of H2 production rate, because it led to more efficient biomass retention. A high biomass concentration of up to 35.4 g VSS/L was achieved even though the reactor was operated at an extremely low HRT (i.e., 0.5 h). In addition to gaining high biomass concentrations, formation of granular sludge also triggered a transition in bacterial community structure, resulting in a nearly twofold increase in the specific H2 production rate. According to denatured-gradient-gel-electrophoresis analysis, operations at a progressively decreasing HRT resulted in a decrease in bacterial population diversity. The culture with the best H2 production performance (at HRT = 0.5 h and sucrose concentration = 30 g COD/L) was eventually dominated by a presumably excellent H2-producing bacterial species identified as Clostridium pasteurianum.

  2. Measurement of $K^{+}$ production in charged-current $\

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, C.M.; et al.

    2016-07-14

    Production of K+ mesons in charged-current νμ interactions on plastic scintillator (CH) is measured using MINERvA exposed to the low-energy NuMI beam at Fermilab. Timing information is used to isolate a sample of 885 charged-current events containing a stopping K+ which decays at rest. The differential cross section in K+ kinetic energy, dσ/dTK, is observed to be relatively flat between 0 and 500 MeV. Its shape is in good agreement with the prediction by the genie neutrino event generator when final-state interactions are included, however the data rate is lower than the prediction by 15%.

  3. Measured radionuclide production from copper, gold and lead spallation targets

    International Nuclear Information System (INIS)

    Spallation target materials are chosen so as to produce large numbers of neutrons while at the same time avoiding the creation of long-lived radioactive wastes. While there has been considerable research to determine the number of neutrons produced per incident particle for various target materials, there has been less effort to precisely quantify the types and amounts of radionuclides produced. Accurate knowledge of the radioactive species produced by spallation reactions is important for specifying waste disposal criteria for targets. In order to verify the production rates calculated by LAHET, a study has been conducted using the Texas A ampersand M University (TAMU) Cyclotron to measure radionuclide yields from copper, gold, and lead targets

  4. Dose-area product measurements in panoramic dental radiology

    International Nuclear Information System (INIS)

    In this study, dose-area product (DAP) measurements in panoramic dental radiology have been performed in Germany. The results obtained in this study were proposed as diagnostic reference levels (DRLs). A representative number of dental panoramic units, both with digital and conventional image receptors, have been chosen. Common statistical parameters such as mean, standard deviation and 3. quartile have been calculated. For four different standard programmes, 'large adult', 'adult male', 'adult female' and 'child', the proposed DRLs are 101, 87, 84 and 75 mGy cm2, respectively. No clear tendency to a generalised dose reduction from the transition to digital techniques has been observed. Effective doses have been calculated from E/DAP conversion factors published in literature. Even though these values differ by a factor of ∼3, upper limits of 15.8-21.2 μSv for the four different exposure settings were derived from the data. (authors)

  5. Measurement of the Charge Asymmetry in Top Quark Pair Production

    Directory of Open Access Journals (Sweden)

    Böser Christian

    2012-06-01

    Full Text Available We present a measurement of the charge asymmetry in top quark pair production using an integrated luminosity of 1.09 fb−1 collected with the CMS detector. Top quark pairs with a signature of one electron or muon and four or more jets, at least one of them b tagged, are selected. At the LHC a small charge asymmetry in the rapidity distributions of top and antitop quarks is predicted. Therein slightly broader rapidity distributions for top quarks are expected, while antitop quarks are produced more centrally and possess narrower rapidity distributions. We determine the charge asymmetry based on two different sensitive variables and the results are compared with the most precise standard model theory predictions using a dedicated unfolding technique.

  6. Measurement of charm production in neutrino charged-current interactions

    CERN Document Server

    Kayis-Topaksu, A

    2011-01-01

    The nuclear emulsion target of the CHORUS detector was exposed to the wide-band neutrino beam of the CERN SPS of 27 GeV average neutrino energy from 1994 to 1997. In total about 100000 charged-current neutrino interactions with at least one identified muon were located in the emulsion target and fully reconstructed, using newly developed automated scanning systems. Charmed particles were searched for by a program recognizing particle decays. The observation of the decay in nuclear emulsion makes it possible to select a sample with very low background and minimal kinematical bias. 2013 charged-current interactions with a charmed hadron candidate in the final state were selected and confirmed through visual inspection. The charm production rate induced by neutrinos relative to the charged-current cross-section is measured to be $\\sigma(\

  7. On Possibility of Detonation Products Temperature Measurements of Emulsion Explosives

    Directory of Open Access Journals (Sweden)

    Silvestrov V. V.

    2014-10-01

    Full Text Available The new view on the structure of the radiance signal recorded by optical pyrometer and the preliminary results of brightness detonation temperature of the emulsion explosive are presented. The structure of an optical signal observed is typical for the heterogeneous explosives. First, there is the short temperature spike to 2500 ÷ 3300 K connecting with a formation of “hot spots” assembly that fire the matrix capable of exothermal reaction. Then the relaxation of radiance to equilibrium level is observed that corresponds to brightness temperature 1840 ÷ 2260 K of explosion products at detonation pressure 1 ÷ 11 GPa. Experimental results are compared with the calculations of other authors. The detonation temperature of the investigated explosive is measured for the first time.

  8. Measurement of Dijet Production at Low $Q^{2}$ at HERA

    CERN Document Server

    Aktas, A; Anthonis, T; Asmone, A; Babaev, A; Backovic, S; Bähr, J; Baranov, P; Barrelet, E; Bartel, Wulfrin; Baumgartner, S; Becker, J; Beckingham, M; Behnke, O; Behrendt, O; Belousov, A; Berger, C; Berger, N; Berndt, T; Bizot, J C; Böhme, J; Boenig, M O; Boudry, V; Bracinik, J; Braunschweig, W; Brisson, V; Broker, H B; Brown, D P; Bruncko, Dusan; Büsser, F W; Bunyatyan, A; Buschhorn, G; Bystritskaya, L; Campbell, A J; Caron, S; Cassol-Brunner, F; Cerny, K; Chekelian, V; Chyla, J; Collard, Caroline; Contreras, J G; Coppens, Y R; Coughlan, J A; Cousinou, M C; Cox, B E; Cozzika, G; Cvach, J; Dainton, J B; Dau, W D; Daum, K; Delcourt, B; Delerue, N; Demirchyan, R A; de Roeck, A; Desch, Klaus; De Wolf, E A; Diaconu, C; Dingfelder, J; Dodonov, V; Dowell, John D; Dubak, A; Duprel, C; Eckerlin, G; Efremenko, V; Egli, S; Eichler, R; Eisele, F; Ellerbrock, M; Elsen, E; Erdmann, M; Erdmann, W; Faulkner, P J W; Favart, L; Fedotov, A; Felst, R; Ferencei, J; Fleischer, M; Fleischmann, P; Fleming, Y H; Flucke, G; Flügge, G; Fomenko, A; Foresti, I; Formánek, J; Franke, G; Frising, G; Gabathuler, Erwin; Gabathuler, K; Garvey, J; Gassner, J; Gayler, J; Gerhards, R; Gerlich, C; Ghazaryan, S; Görlich, L; Gogitidze, N; Gorbounov, S; Grab, C; Grabskii, V; Grässler, Herbert; Greenshaw, T; Gregori, M; Grindhammer, G; Haidt, Dieter; Hajduk, L; Haller, J; Heinzelmann, G; Henderson, R C W; Henschel, H; Henshaw, O; Heremans, R; Herrera-Corral, G; Herynek, I; Heuer, R D; Hildebrandt, M; Hiller, K H; Hladky, J; Hoting, P; Hoffmann, D; Horisberger, R P; Hovhannisyan, A V; Ibbotson, M; Ismail, M; Jacquet, M; Janauschek, L; Janssen, X; Jemanov, V; Jönsson, L B; Johnson, C; Johnson, D P; Jung, H; Kant, D; Kapichine, M; Karlsson, M; Katzy, J; Keller, N; Kennedy, J; Kenyon, I R; Kiesling, C; Klein, M; Kleinwort, C; Kluge, T; Knies, G; Knutsson, A; Koblitz, B; Kolya, S D; Korbel, V; Kostka, P; Koutouev, R; Kropivnitskaya, A; Kroseberg, J; Kuckens, J; Kuhr, T; Landon, M P J; Lange, W; Lastoviicka, T; Laycock, P; Lebedev, A; Leiner, B; Lemrani, R; Lendermann, V; Levonian, S; List, B; Lobodzinska, E; Loktionova, N A; López-Fernandez, R; Lubimov, V; Lüders, H; Lüders, S; Lüke, D; Lux, T; Lytkin, L; Makankine, A; Malden, N; Malinovskii, E I; Mangano, S; Marage, P; Marks, J; Marshall, R; Martisikova, M; Martyn, H U; Martyniak, J; Maxfield, S J; Meer, D; Mehta, A; Meier, K; Meyer, A B; Meyer, H; Meyer, J; Michine, S; Mikocki, S; Milcewicz, I; Milstead, D; Moreau, F; Morozov, A; Morozov, I; Morris, J V; Mozer, M; Müller, K; Murn, P; Nagovizin, V; Naroska, Beate; Naumann, J; Naumann, T; Newman, P R; Niebuhr, C B; Nikitin, D K; Nowak, G; Nozicka, M; Olivier, B; Olsson, J E; Ossoskov, G; Ozerov, D; Pascaud, C; Patel, G D; Peez, M; Pérez, E; Perieanu, A; Petrukhin, A; Pitzl, D; Pöschl, R; Portheault, B; Povh, B; Raicevic, N; Rauschenberger, J; Reimer, P; Reisert, B; Risler, C; Rizvi, E; Robmann, P; Roosen, R; Rostovtsev, A A; Rurikova, Z; Rusakov, S V; Rybicki, K; Sankey, D P C; Sauvan, E; Schatzel, S; Scheins, J; Schilling, F P; Schleper, P; Schmidt, S; Schmitt, S; Schneider, M; Schoeffel, L; Schöning, A; Schröder, V; Schultz-Coulon, H C; Schwanenberger, C; Sedlak, K; Sefkow, F; Shevyakov, I; Shtarkov, L N; Sirois, Y; Sloan, T; Smirnov, P; Soloviev, Yu; South, D; Spaskov, V N; Specka, A E; Spitzer, H; Stamen, R; Stella, B; Stiewe, J; Strauch, I; Straumann, U; Tasevsky, M; Thompson, G; Thompson, P D; Tomasz, F; Traynor, D; Truöl, P; Tsipolitis, G; Tsurin, I; Turnau, J; Tzamariudaki, E; Uraev, A; Urban, M; Usik, A; Valkár, S; Valkárová, A; Vallée, C; Van Mechelen, P; Vargas-Trevino, A; Vasilev, S; Vazdik, Ya A; Veelken, C; Vest, A; Vichnevski, A; Vinokurova, S; Volchinski, V; Wacker, K; Wagner, J; Waugh, B; Weber, G; Weber, R; Wegener, D; Werner, C; Werner, N; Wessels, M; Wessling, B; Winde, M; Winter, G G; Wissing, C; Woerling, E E; Wünsch, E; Yan, W; Zácek, J; Zaleisak, J; Zhang, Z; Zhokin, A; Zohrabyan, H G; Zomer, F

    2004-01-01

    Triple differential dijet cross sections in e^\\pm p interactions are presented in the region of photon virtualities 27GeV, E_T2>5GeV, and pseudorapidities -2.5 < eta_1^*, eta_2^* <0. The measurements are made in the gamma^* p centre-of-mass frame, using an integrated luminosity of 57pb^-1. The data are compared with NLO QCD calculations and LO Monte Carlo programs with and without a resolved virtual photon contribution. NLO QCD calculations fail to describe the region of low Q^2 and low jet transverse energies, in contrast to a LO Monte Carlo generator which includes direct and resolved photon interactions with both transversely and longitudinally polarised photons. Initial and final state parton showers are tested as a mechanism for including higher order QCD effects in low E_T jet production.

  9. Production of bacterial blight resistant lines from somatic hybridization between Oryza sativa L. and Oryza meyeriana L.

    Institute of Scientific and Technical Information of China (English)

    严成其; 钱凯先; 薛刚平; 吴忠长; 陈跃磊; 颜秋生; 张雪琴; 吴平

    2004-01-01

    Novel bacterial blight (BB) resistance gene(s) for rice was (were) introduced into a cultivated japonica rice variety Oryza sativa (cv. 8411), via somatic hybridization using the wild rice Oryza meyeriana as the donor of the resistance gene(s). Twenty-nine progenies of somatically hybridized plants were obtained. Seven somatically hybridized plants and their parents were used for AFLP (amplified fragment length polymorphism) analysis using 8 primer pairs. Results confirmed that these plants were somatic hybrids containing the characteristic bands of both parents. The morphology of the regenerated rice showed characters of both O.sativa and O.meyeriana. Two somatic hybrids showed highest BB resistance and the other 8 plants showed moderate resistance. The new germplasms with highest resistance have been used in the rice breeding program for the improvement of bacterial blight resistance.

  10. Production of bacterial blight resistant lines from somatic hybridization between Oryza sativa L.and Oryza meyeriana L.

    Institute of Scientific and Technical Information of China (English)

    严成其; 钱凯先; 薛刚平; 吴忠长; 陈跃磊; 颜秋生; 张雪琴; 吴平

    2004-01-01

    Novel bacterial blight (BB) resistance gene(s) for rice was (were) introduced into a cultivated japonica rice variety Oryza sativa (cv. 8411), via somatic hybridization using the wild rice Oryza meyeriana as the donor of the resistance gene(s). Twenty-nine progenies of somatically hybridized plants were obtained. Seven somatically hybridized plants and their parents were used for AFLP (amplified fragment length polymorphism) analysis using 8 primer pairs. Results confirmed that these plants were somatic hybrids containing the characteristic bands of both parents. The morphology of the regenerated rice showed characters of both O. sativa and O. meyeriana. Two somatic hybrids showed highest BB resistance and the other 8 plants showed moderate resistance. The new germplasms with highest resistance have been used in the rice bfeeding program for the improvement of bacterial blight resistance.

  11. Biological hydrogen production measured in batch anaerobic respirometers.

    Science.gov (United States)

    Logan, Bruce E; Oh, Sang-Eun; Kim, In S; Van Ginkel, Steven

    2002-06-01

    The biological production of hydrogen from the fermentation of different substrates was examined in batch tests using heat-shocked mixed cultures with two techniques: an intermittent pressure release method (Owen method) and a continuous gas release method using a bubble measurement device (respirometric method). Under otherwise identical conditions, the respirometric method resulted in the production of 43% more hydrogen gas from glucose than the Owen method. The lower conversion of glucose to hydrogen using the Owen protocol may have been produced by repression of hydrogenase activity from high partial pressures in the gastight bottles, but this could not be proven using a thermodynamic/rate inhibition analysis. In the respirometric method, total pressure in the headspace never exceeded ambient pressure, and hydrogen typically composed as much as 62% of the headspace gas. High conversion efficiencies were consistently obtained with heat-shocked soils taken at different times and those stored for up to a month. Hydrogen gas composition was consistently in the range of 60-64% for glucose-grown cultures during logarithmic growth but declined in stationary cultures. Overall, hydrogen conversion efficiencies for glucose cultures were 23% based on the assumption of a maximum of 4 mol of hydrogen/ mol of glucose. Hydrogen conversion efficiencies were similar for sucrose (23%) and somewhat lower for molasses (15%) but were much lower for lactate (0.50%) and cellulose (0.075%).

  12. Particle-associated bacterial dynamics in a tropical tidal plain (Zuari estuary, India)

    Digital Repository Service at National Institute of Oceanography (India)

    DeSouza, M.J.B.D.; Nair, S.; LokaBharathi, P.A.; Chandramohan, D.

    The dynamics of particle-associated bacteria (PAB) in a tropical estuary, Zuari, in Goa on the west coast of India, was studied for a year from September 1997 to October 1998. Bacterial abundance, productivity and enzymatic activities were measured...

  13. The influence of bacterial-humus preparations on the biological activity of soils polluted with oil products and heavy metals

    Science.gov (United States)

    Kozlova, E. N.; Stepanov, A. L.; Lysak, L. V.

    2015-04-01

    The influence of bacterial-humus preparations based on Gumigel ( Agrosintez Company) on the biological activity of soddy-podzolic soil polluted with Pb(CH3COO)2 and gasoline was studied in a model experiment. Some indicators of biological activity are shown to depend on soil pollution to different extents. The process of nitrogen fixation and the activity of dehydrogenase and phosphatase were mostly inhibited by Pb(CH3COO)2 and gasoline. Gasoline compared to Pb(CH3COO)2 inhibited the soil biological activity to a greater extent. The bacterial-humus preparations exerted a significant positive effect on the biological activity of the polluted soils manifested in the increase of the total number of bacteria and of the enzyme activity (1.5-5.0 times), in the intensification of nitrogen fixation and denitrification (3-8 times), as well as in the increase in the biomass of the plants grown (1.5-2.0 times). The application of bacterial suspensions of pure cultures or the microbial complex without the preparations of humic acids did not always give a positive effect.

  14. Product intelligence: its conceptualization, measurement and impact on consumer satisfaction

    OpenAIRE

    Rijsdijk, Serge; Hultink, Erik Jan; Diamantopoulos, Adamantios

    2007-01-01

    textabstractIn the last decade, companies have developed a large number of intelligent products. Due to the use of information technology, these products, for example, are able to work autonomously, cooperate with other products, or adapt to changing circumstances. Although intelligent products appear an attractive category of products, they have received little attention in the literature. The present article provides a conceptualization of the new construct of product intelligence and descr...

  15. Measurement of open beauty production in photoproduction at HERA

    CERN Document Server

    Breitweg, J; Derrick, Malcolm; Krakauer, D A; Magill, S; Musgrave, B; Pellegrino, A; Repond, J; Stanek, R; Yoshida, R; Mattingly, M C K; Antonioli, P; Bari, G; Basile, M; Bellagamba, L; Boscherini, D; Bruni, A; Bruni, G; Cara Romeo, G; Cifarelli, Luisa; Cindolo, F; Contin, A; Corradi, M; De Pasquale, S; Giusti, P; Iacobucci, G; Levi, G; Margotti, A; Massam, Thomas; Nania, R; Palmonari, F; Pesci, A; Sartorelli, G; Zichichi, A; Aghuzumtsyan, G; Amelung, C; Brock, I; Coboken, K; Goers, S; Hartmann, H; Heinloth, K; Hilger, E; Irrgang, P; Jakob, H P; Kappes, A; Katz, U F; Kerger, R; Kind, O; Paul, E; Rautenberg, J; Schnurbusch, H; Stifutkin, A; Tandler, J; Voss, K C; Weber, A; Wieber, H; Bailey, D S; Barret, O; Brook, N H; Cole, J E; Foster, B; Heath, G P; Heath, H F; Robins, S A; Rodrigues, E; Scott, J; Tapper, R J; Capua, M; Mastroberardino, A; Schioppa, M; Susinno, G; Jeoung, H Y; Kim, J Y; Lee, J H; Lim, I T; Ma, K J; Pac, M Y; Caldwell, A; Liu, W; Liu, X; Mellado, B; Paganis, S; Sampson, S; Schmidke, W B; Sciulli, F; Chwastowski, J; Eskreys, Andrzej; Figiel, J; Klimek, K H; Olkiewicz, K; Piotrzkowski, K; Przybycien, M B; Stopa, P; Zawiejski, L; Bednarek, B; Jelen, K; Kisielewska, D; Kowal, A M; Kowalski, T; Rulikowska-Zarebska, E; Suszycki, L; Szuba, D; Bauerdick, L A T; Behrens, U; Bienlein, J K; Borras, K; Chiochia, V; Crittenden, James Arthur; Dannheim, D; Desler, K; Drews, G; Fox-Murphy, A; Fricke, U; Göbel, F; Göttlicher, P; Graciani, R; Haas, T; Hain, W; Hartner, G F; Hebbel, K; Hillert, S; Koch, W; Kötz, U; Kowalski, H; Labes, H; Löhr, B; Mankel, R; Martens, J; Martínez, M; Milite, M; Moritz, M; Notz, D; Petrucci, M C; Polini, A; Rohde, M; Savin, A A; Schneekloth, U; Selonke, F; Sievers, M; Stonjek, S; Wolf, G; Wollmer, U; Youngman, C; Zeuner, W; Coldewey, C; López-Duran-Viani, A; Meyer, A; Schlenstedt, S; Straub, P B; Barbagli, G; Gallo, E; Parenti, A; Pelfer, P G; Bamberger, Andreas; Benen, A; Coppola, N; Eisenhardt, S; Markun, P; Raach, H; Wölfle, S; Bussey, Peter J; Bell, M; Doyle, A T; Glasman, C; Lee, S W; Lupi, A; MacDonald, N; McCance, G J; Saxon, D H; Sinclair, L E; Skillicorn, Ian O; Waugh, R; Bodmann, B; Gendner, N; Holm, U; Salehi, H; Wick, K; Yildirim, A; Carli, T; Garfagnini, A; Geiser, A; Gialas, I; Kcira, D; Klanner, Robert; Lohrmann, E; Goncalo, R; Long, K R; Miller, D B; Tapper, A D; Walker, R; Cloth, P; Filges, D; Ishii, T; Kuze, M; Nagano, K; Tokushuku, K; Yamada, S; Yamazaki, Y; Boos, E G; Pokrovskiy, N S; Zhautykov, B O; Barakbaev, A N; Ahn, S H; Lee, S B; Park, S K; Lim, H; Son, D; Barreiro, F; García, G; González, O; Labarga, L; Del Peso, J; Redondo, I; Terron, J; Vázquez, M E; Barbi, M S; Corriveau, F; Padhi, S; Stairs, D G; Wing, M; Tsurugai, T; Antonov, A; Bashkirov, V; Danilov, M V; Dolgoshein, B A; Gladkov, D; Sosnovtsev, V V; Suchkov, S; Dementiev, R K; Ermolov, P F; Golubkov, Yu A; Katkov, I I; Khein, L A; Korotkova, N A; Korzhavina, I A; Kuzmin, V A; Lukina, O Yu; Proskuryakov, A S; Shcheglova, L M; Solomin, A N; Vlasov, N N; Zotkin, S A; Bokel, C; Botje, M; Brümmer, N; Engelen, J; Grijpink, S; Koffeman, E; Kooijman, P M; Schagen, S; Van Sighem, A; Tassi, E; Tiecke, H G; Tuning, N; Velthuis, J J; Vossebeld, Joost Herman; Wiggers, L; De Wolf, E; Bylsma, B; Durkin, L S; Gilmore, J; Ginsburg, C M; Kim, C L; Ling, T Y; Boogert, S; Cooper-Sarkar, A M; Devenish, R C E; Grosse-Knetter, J; Matsushita, T; Ruske, O; Sutton, M R; Walczak, R; Bertolin, A; Brugnera, R; Carlin, R; Dal Corso, F; Dusini, S; Limentani, S; Longhin, A; Posocco, M; Stanco, L; Turcato, M; Adamczyk, L; Iannotti, L; Oh, B Y; Okrasinski, J R; Saull, P R B; Toothacker, W S; Whitmore, J J; Iga, Y; D'Agostini, Giulio; Marini, G; Nigro, A; Cormack, C; Hart, J C; McCubbin, N A; Shah, T P; Epperson, D E; Heusch, C A; Sadrozinski, H F W; Seiden, A; Wichmann, R; Williams, D C; Park, I H; Pavel, N; Abramowicz, H; Dagan, S; Gabareen, A; Kananov, S; Kreisel, A; Levy, A; Abe, T; Fusayasu, T; Kohno, T; Umemori, K; Yamashita, T; Hamatsu, R; Hirose, T; Inuzuka, M; Kitamura, S; Matsuzawa, K; Nishimura, T; Arneodo, M; Cartiglia, N; Cirio, R; Costa, M; Ferrero, M I; Maselli, S; Monaco, V; Peroni, C; Ruspa, M; Sacchi, R; Solano, A; Staiano, A; Bailey, D C; Fagerstroem, C P; Galea, R; Koop, T; Levman, G M; Martin, J F; Mirea, A; Sabetfakhri, A; Butterworth, J M; Gwenlan, C; Hayes, M E; Heaphy, E A; Jones, T W; Lane, J B; West, B J; Ciborowski, J; Ciesielski, R; Grzelak, G; Nowak, R J; Pawlak, J M; Pawlak, R; Smalska, B; Tymieniecka, T; Wróblewski, A K; Zakrzewski, J A

    2001-01-01

    The production and semi-leptonic decay of heavy quarks have been studied in the photoproduction process $e^+p -> e^+ + {dijet} + e^- + X with the ZEUS detector at HERA using an integrated luminosity of 38.5 ${\\rm pb^{-1}}$. Events with photon-proton centre-of-mass energies, $W_{\\gamma p}$, between 134 and 269 GeV and a photon virtuality, Q^2, less than 1 ${\\rm GeV^2}$ were selected requiring at least two jets of transverse energy $E_T^{\\rm jet1(2)} >7(6)$ GeV and an electron in the final state. The electrons were identified by employing the ionisation energy loss measurement. The contribution of beauty quarks was determined using the transverse momentum of the electron relative to the axis of the closest jet, $p_T^{\\rm rel}$. The data, after background subtraction, were fit with a Monte Carlo simulation including beauty and charm decays. The measured beauty cross section was extrapolated to the parton level with the b quark restricted to the region of transverse momentum $p_T^{b} > p_T^{\\rm min} =$ 5 GeV and ...

  16. Measurement of open beauty production in photoproduction at HERA

    Science.gov (United States)

    ZEUS Collaboration; Breitweg, J.; et al.

    2001-01-01

    The production and semi-leptonic decay of heavy quarks have been studied in the photoproduction process e+p -> e+ + dijet + e- + X with the ZEUS detector at HERA using an integrated luminosity of 38.5 pb -1. Events with photon-proton centre-of-mass energies, Wγ p, between 134 and 269 GeV and a photon virtuality, Q2, less than 1 GeV 2 were selected requiring at least two jets of transverse energy ET jet1(2) >7(6) GeV and an electron in the final state. The electrons were identified by employing the ionisation energy loss measurement. The contribution of beauty quarks was determined using the transverse momentum of the electron relative to the axis of the closest jet, pT rel. The data, after background subtraction, were fit with a Monte Carlo simulation including beauty and charm decays. The measured beauty cross section was extrapolated to the parton level with the b quark restricted to the region of transverse momentum pT^b > pT^min = 5 GeV and pseudorapidity |η b| < 2. The extrapolated cross section is 1.6 +/- 0.4 (stat.)+0.3-0.5 (syst.) +0.2-0.4 (ext.) nb. The result is compared to a perturbative QCD calculation performed to next-to-leading order.

  17. Bacterial CD1d-restricted glycolipids induce IL-10 production by human regulatory T cells upon cross-talk with invariant NKT cells.

    Science.gov (United States)

    Venken, Koen; Decruy, Tine; Aspeslagh, Sandrine; Van Calenbergh, Serge; Lambrecht, Bart N; Elewaut, Dirk

    2013-09-01

    Invariant NKT (iNKT) cells and CD4(+)CD25(+)FOXP3(+) regulatory T cells (Tregs) are important immune regulatory T cells with Ag reactivity to glycolipids and peptides, respectively. However, the functional interplay between these cells in humans is poorly understood. We show that Tregs suppress iNKT cell proliferation induced by CD1d-restricted glycolipids, including bacterial-derived diacylglycerols, as well as by innate-like activation. Inhibition was related to the potency of iNKT agonists, making diacylglycerol iNKT responses very prone to suppression. Cytokine production by iNKT cells was differentially modulated by Tregs because IL-4 production was reduced more profoundly compared with IFN-γ. A compelling observation was the significant production of IL-10 by Tregs after cell contact with iNKT cells, in particular in the presence of bacterial diacylglycerols. These iNKT-primed Tregs showed increased FOXP3 expression and superior suppressive function. Suppression of iNKT cell responses, but not conventional T cell responses, was IL-10 dependent, suggesting that there is a clear difference in mechanism between the Treg-mediated inhibition of these cell types. Our data highlight a physiologically relevant interaction between human iNKT and Tregs upon pathogen-derived glycolipid recognition that has a significant impact on the design of iNKT cell-based therapeutics.

  18. Surface-attached and suspended bacterial community structure as affected by C/N ratios: relationship between bacteria and fish production.

    Science.gov (United States)

    Yu, Ermeng; Xie, Jun; Wang, Jinlin; Ako, Harry; Wang, Guangjun; Chen, Zhanghe; Liu, Yongfeng

    2016-07-01

    Bacteria play crucial roles in the combined system of substrate addition and C/N control, which has been demonstrated to improve aquaculture production. However, the complexity of surface-attached bacteria on substrates and suspended bacteria in the water column hamper further application of this system. This study firstly applied this combined system into the culture of grass carp, and then explored the relationship between microbial complexes from surface-attached and suspended bacteria in this system and the production of grass carp. In addition, this study investigated bacterial community structures as affected by four C/N ratios using Illumina sequencing technology. The results demonstrated that the weight gain rate and specific growth rate of grass carp in the CN20 group (C/N ratio 20:1) were the highest (P production of grass carp, and Verrucomicrobiae and Rhodobacter in the surface-attached bacterial community were potential probiotic bacteria that contributed to the enhanced growth of grass carp. PMID:27263011

  19. Selection of potent bacterial strain for over-production of PHB by using low cost carbon source for eco-friendly bioplastics

    Directory of Open Access Journals (Sweden)

    Rahat Abdul Rehman

    2015-11-01

    Full Text Available Background: The microbial PHB production is a promising tool for the plastic industry for the synthesis of environmental friendly, biodegradable plastic in contrast to the conventional petro-chemical based non-degradable plastics. The selection of potent bacterial strains, inexpensive carbon source, efficient fermentation and recovery processes are important aspects that were taken into account during this study. Methods: Different bacterial strains i.e. Bacillus Spp, P. putida and P. fluorescens were screened for maximum PHB production. Under media optimization, various carbon and nitrogen sources (alone or in combination were used to achieve the maximum PHB production. Finally the degradation tests of the PHB sheet were also performed to test its biodegradability potential. Results: Shake flask studies have shown the PHB concentrations upto 7.02, 4.50 and 34.4 mg/g of dry cell mass of P. putida, P. fluorescens and Bacillus Spp. respectively. Almost same results were observed at laboratory scale production of PHB in 10 L fermenter i.e. 6.28, 6.23 and 39.5 mg/g of dry cell mass by P. putida, P. fluorescens and Bacillus Spp. respectively. On the basis of these observations, Bacillus Spp. was chosen for laboratory scale PHB production. Corn steep liquor (4% was chosen as the best medium to achieve the highest PHB contents. Isolated PHB has shown biodegradation in soil up to 86.7% at 37oC. Conclusion: The Bacillus Spp. Proved to be the best strain for PHB production on only 4% CSL which is cheapest and easily available.

  20. Biodegradability of Poly-3-hydroxybutyrate/Bacterial Cellulose Composites under Aerobic Conditions, Measured via Evolution of Carbon Dioxide and Spectroscopic and Diffraction Methods.

    Science.gov (United States)

    Ruka, Dianne R; Sangwan, Parveen; Garvey, Christopher J; Simon, George P; Dean, Katherine M

    2015-08-18

    Poly-3-hydroxybutyrate (PHB) and bacterial cellulose (BC) are both natural polymeric materials that have the potential to replace traditional, nonrenewable polymers. In particular, the nanofibrillar form of bacterial cellulose makes it an effective reinforcement for PHB. Neat PHB, bacterial cellulose, and a composite of PHB/BC produced with 10 wt % cellulose were composted under accelerated aerobic test conditions, with biodegradability measured by the carbon dioxide evolution method, in conjunction with spectroscopic and diffraction methods to assess crystallinity changes during the biodegradation process. The PHB/BC composite biodegraded at a greater rate and extent than that of PHB alone, reaching 80% degradation after 30 days, whereas PHB did not reach this level of degradation until close to 50 days of composting. The relative crystallinity of PHB and PHB in the PHB/BC composite was found to increase in the initial weeks of degradation, with degradation occurring primarily in the amorphous region of the material and some recrystallization of the amorphous PHB. Small angle X-ray scattering indicates that the change in PHB crystallinity is accompanied by a change in morphology of semicrystalline lamellae. The increased rate of biodegradability suggests that these materials could be applicable to single-use applications and could rapidly biodegrade in compost on disposal.

  1. Isolation of a Siderophore-Producting Bacterial Strain and Mica-bacterial Interactions%一株产铁载体细菌的筛选及其与云母的相互作用

    Institute of Scientific and Technical Information of China (English)

    何琳燕; 张垠; 盛下放; 黄智

    2012-01-01

    Studies on the interactions between siderophore-producting bacteria and mica minerals will help us understand the mechanism of bio-weathering, the formation of soil, global cycle of several elements, and local environmental contamination. A siderophore(pyoverdins)-producting bacterial strain Z6 was isolated from rhizosphere soil of advantage wild plants sheep sorrel (Rumex acetosa L.) growing in Longshan potassium mine tailings in Nanjing, which was identified as Pseudomonas sp. By checking the individual morphology, colony characteristics, and 16S rDNA sequencing. Using the test cultures containing biotite or muscovite inoculated with Pseudomonas sp. Z6, we found that a strong increase in the amount of siderophore in the fiest 15 days and bacteria could influence silicon and iron mobilization from mica minerals consistently until 75 d of culture. The amounts of iron released from biotite in the presence of Z6 increased by 211 times and the silicon increased by a factor of 27.8, much higher than that in the negative control without minerals. SEM analysis revealed the formation of erosion and bacteria-mineral aggregates on the surface of mica. Cellular growth, siderophere production and pH change by Pseudomonas sp. Z6 cultivated in biotite were directly and quickly influenced, more significantly than that in muscovite experimental setup. The siderophore(pyoverdins)-producting bacterial strain Z6 might play an important role in the process of mica weathering. Production of bacterial siderophore may be related to the presence of different mica minerals.%产铁载体细菌与云母类矿物相互作用的研究有助于了解矿物生物风化和土壤形成的演化规律和机理.采用纯培养法自南京龙山废钾矿区酸模根际土壤分离筛选到一株高产荧光铁载体的细菌Z6,通过16S rDNA序列分析和生理生化反应将其鉴定为假单胞菌属(Pseudomonas sp.);通过室温静置培养试验研究Z6菌株与云母的相互作用结果

  2. Product Intelligence: Its Conceptualization, Measurement and Impact on Consumer Satisfaction

    NARCIS (Netherlands)

    S.A. Rijsdijk (Serge); E.J. Hultink (Erik Jan); A. Diamantopoulos (Adamantios)

    2007-01-01

    textabstractIn the last decade, companies have developed a large number of intelligent products. Due to the use of information technology, these products, for example, are able to work autonomously, cooperate with other products, or adapt to changing circumstances. Although intelligent products appe

  3. A Criteria-based Measure of Similarity between Product Functionalities

    OpenAIRE

    Politze, D. P.; Dierssen, S.

    2009-01-01

    Today‘s customers request product functions and not components. A specific, modular description of the product functions and how they are realized becomes widely accepted to track how a product function is realized and to support future development. This will result in an additional, modular product structure from a functional viewpoint that is orthogonal to the physical product structure. Because the extent of each functional module has to be defined according to some kind of sim...

  4. Net production and consumption of fluorescent colored dissolved organic matter by natural bacterial assemblages growing on marine phytoplankton exudates.

    Science.gov (United States)

    Romera-Castillo, Cristina; Sarmento, Hugo; Alvarez-Salgado, Xosé Antón; Gasol, Josep M; Marrasé, Celia

    2011-11-01

    An understanding of the distribution of colored dissolved organic matter (CDOM) in the oceans and its role in the global carbon cycle requires a better knowledge of the colored materials produced and consumed by marine phytoplankton and bacteria. In this work, we examined the net uptake and release of CDOM by a natural bacterial community growing on DOM derived from four phytoplankton species cultured under axenic conditions. Fluorescent humic-like substances exuded by phytoplankton (excitation/emission [Ex/Em] wavelength, 310 nm/392 nm; Coble's peak M) were utilized by bacteria in different proportions depending on the phytoplankton species of origin. Furthermore, bacteria produced humic-like substances that fluoresce at an Ex/Em wavelength of 340 nm/440 nm (Coble's peak C). Differences were also observed in the Ex/Em wavelengths of the protein-like materials (Coble's peak T) produced by phytoplankton and bacteria. The induced fluorescent emission of CDOM produced by prokaryotes was an order of magnitude higher than that of CDOM produced by eukaryotes. We have also examined the final compositions of the bacterial communities growing on the exudates, which differed markedly depending on the phytoplankton species of origin. Alteromonas and Roseobacter were dominant during all the incubations on Chaetoceros sp. and Prorocentrum minimum exudates, respectively. Alteromonas was the dominant group growing on Skeletonema costatum exudates during the exponential growth phase, but it was replaced by Roseobacter afterwards. On Micromonas pusilla exudates, Roseobacter was replaced by Bacteroidetes after the exponential growth phase. Our work shows that fluorescence excitation-emission matrices of CDOM can be a helpful tool for the identification of microbial sources of DOM in the marine environment, but further studies are necessary to explore the association of particular bacterial groups with specific fluorophores. PMID:21742918

  5. Synthesis and Anti-Bacterial Activities of a Bis-Chalcone Derived from Thiophene and Its Bis-Cyclized Products

    OpenAIRE

    Asiri, Abdullah M.; Khan, Salman A.

    2011-01-01

    A chalcone was prepared by the reaction of terephthalaldehyde with 3-acetyl-2,5-dimethylthiophene. Treatment of this chalcone with thiosemicarbazide/phenyl hydrazine/guanidine hydrochloride/thiourea afforded the corresponding pyrazoline,  pyrazole, and pyrimidine in good yields. All the new compounds have been characterized by IR, 1H-NMR, 13C-NMR, GC-MS and elemental analyses. The anti-bacterial activity of these compounds were first tested in vitro by the disk diffusion assay against two Gra...

  6. Bacterial surface adaptation

    Science.gov (United States)

    Utada, Andrew

    2014-03-01

    Biofilms are structured multi-cellular communities that are fundamental to the biology and ecology of bacteria. Parasitic bacterial biofilms can cause lethal infections and biofouling, but commensal bacterial biofilms, such as those found in the gut, can break down otherwise indigestible plant polysaccharides and allow us to enjoy vegetables. The first step in biofilm formation, adaptation to life on a surface, requires a working knowledge of low Reynolds number fluid physics, and the coordination of biochemical signaling, polysaccharide production, and molecular motility motors. These crucial early stages of biofilm formation are at present poorly understood. By adapting methods from soft matter physics, we dissect bacterial social behavior at the single cell level for several prototypical bacterial species, including Pseudomonas aeruginosa and Vibrio cholerae.

  7. Evidence for WZ Production and a Measurement of the WZ Production Cross Section

    Energy Technology Data Exchange (ETDEWEB)

    Degenhardt, James D.; /Michigan U.

    2007-05-01

    This dissertation describes a test of the Standard Model (SM) of particle physics by measuring the probability, or cross section, of simultaneously producing a W boson and a Z boson from proton-antiproton collisions. The SM predicts the cross section of WZ production to be 3.68 {+-} 0.25 pb. The SM and physics of WZ production are described in Chapter 2 of this dissertation. The 1.96 TeV center-of-mass energy proton-antiproton collisions are provided by the Fermi National Accelerator Laboratory (FNAL) Tevatron Collider. The W and Z particles are detected using the D0 detector, which is described in Chapter 3. The data were collected by the detector during 2002-2006 corresponding to 1 fb{sup -1} of p{bar p} collisions. This data set is described in Chapter 6. The measurement uses the trilepton (e{nu}ee, {mu}{nu}ee, e{nu}{mu}{mu}, and {mu}{nu}{mu}{mu}) decay channels, in which a W decays to a charged lepton plus a neutrino and a Z decays to a pair of charged leptons. The W and Z particle selection criteria, detection efficiency, and background determination are described in Chapter 7. We observe 13 candidate events in 1 fb{sup -1} of p{bar p} collisions. In this data set we expect to see 4.5 {+-} 0.6 background events, and we expect to see 9.2 {+-} 1.0 signal events. The probability of 4.5 {+-} 0.6 background events to fluctuate to 13 or more events is 1.2 x 10{sup -3} which is a 3.0 {sigma} deviation from the background estimate. A log likelihood method is used to determine the most likely cross section as determined by the measured signal efficiencies, the expected backgrounds, and the observed data. Presented in Chapter 8 is a measurement of the cross section for p{bar p} {yields} WZ + X at {radical}s = 1.96 TeV. The WZ diboson production cross section is measured to be {sigma}{sub WZ} = 2.7{sub -1.3}{sup +1.7} pb. This is in agreement with the predicted Standard Model cross section.

  8. Evidence for WZ Production and a Measurement of the WZ Production Cross Section

    Energy Technology Data Exchange (ETDEWEB)

    Degenhardt, James D. [Univ. of Michigan, Ann Arbor, MI (United States)

    2007-05-01

    This dissertation describes a test of the Standard Model (SM) of particle physics by measuring the probability, or cross section, of simultaneously producing a W boson and a Z boson from proton-antiproton collisions. The SM predicts the cross section of WZ production to be 3.68 ± 0.25 pb. The SM and physics of WZ production are described in Chapter 2 of this dissertation. The 1.96 TeV center-of-mass energy proton-antiproton collisions are provided by the Fermi National Accelerator Laboratory (FNAL) Tevatron Collider. The W and Z particles are detected using the D0 detector, which is described in Chapter 3. The data were collected by the detector during 2002-2006 corresponding to 1 fb-1 of p{bar p} collisions. This data set is described in Chapter 6. The measurement uses the trilepton (evee, μvee, evμμ, and μvμμ) decay channels, in which a W decays to a charged lepton plus a neutrino and a Z decays to a pair of charged leptons. The W and Z particle selection criteria, detection efficiency, and background determination are described in Chapter 7. We observe 13 candidate events in 1 fb-1 of p$\\bar{p}$ collisions. In this data set we expect to see 4.5 ± 0.6 background events, and we expect to see 9.2 ± 1.0 signal events. The probability of 4.5 ± 0.6 background events to fluctuate to 13 or more events is 1.2 x 10-3 which is a 3.0 σ deviation from the background estimate. A log likelihood method is used to determine the most likely cross section as determined by the measured signal efficiencies, the expected backgrounds, and the observed data. Presented in Chapter 8 is a measurement of the cross section for p$\\bar{p}$ → WZ + X at √s = 1.96 TeV. The WZ diboson production cross section is measured to be σWZ = 2.7$+1.7\\atop{-1.3}$ pb. This is in agreement with the predicted Standard Model cross section.

  9. The methodical substantiation of measures to improve the use of basic production assets of the enterprise

    Directory of Open Access Journals (Sweden)

    Korol Svetlana Anatolevna

    2013-07-01

    Full Text Available The method of calculating the performance measures to improve the use of basic production assets of the enterprise: production cost, production volume, number of additional workers, depreciation and amortization.

  10. Electrical measuring device, method and computer program product

    NARCIS (Netherlands)

    Meijer G.C.M.; Hilhorst, M.A.

    2008-01-01

    The invention relates to an electrical measuring device for performing an electrical -impedance measurement in a contactless manner. The measuring device comprises a measuring unit which is provided with the impedance (7,8) to be measured and a passive resonance circuit (4) connected thereto for gen

  11. Changes in production efficiency in China identification and measuring

    CERN Document Server

    Xu, Bing; Watada, Junzo

    2014-01-01

    Evaluating  Production Efficiency in China examines production from engineering and statistics perspectives rather than from economics and mathematics perspectives. The authors present an observable benchmark as the criterion of the production efficiency to replace the unobservable production frontier surface. This book discusses several different computing technologies, controllable variable as a path of identification, changes in production efficiency by decision making on specific operating conditions, and optimal resource allocation. The book provides a channel to tap inside the success stories of China, exploiting the way of changes in production efficiency during China’s development in the past 30 years. This book examines the concepts and realization of production efficiencies across all areas of the economy. Also the book provides the perspective of foreign direct investment (FDI) absorption to identify how Chinese economy changes in production efficiency.

  12. R&D and Productivity: Measurement Issues and Econometric Results.

    Science.gov (United States)

    Griliches, Zvi

    1987-01-01

    Discusses the relationship and contributions of research and development (R&D) to productivity growth in the United States. Focuses on the impacts of industrial R&D and presents study results on trends in productivity. (ML)

  13. Postoperative changes in fecal bacterial communities and fermentation products in obese patients undergoing bilio-intestinal bypass

    Directory of Open Access Journals (Sweden)

    Vania ePatrone

    2016-02-01

    Full Text Available We assessed the gut microbial ecology of 11 severely obese patients before and after bilio-intestinal bypass (BIB. Fecal samples were evaluated for microbial communities using 16S rDNA Illumina sequencing, real-time PCR targeting functional genes, and gas chromatography of short chain fatty acids (SCFAs. At 6 months after surgery, subjects exhibited significant improvements in metabolic markers (body weight, glucose, and lipid metabolism compared with baseline. The fecal microbiota of post-surgery individuals was characterized by an overall decrease of bacterial diversity, with a significant reduction in Lachnospiraceae, Clostridiaceae, Ruminococcaceae, Eubacteriaceae, and Coriobacteriaceae. On the contrary, there were significant increases of genera Lactobacillus, Megasphaera, and Acidaminococcus and the family Enterobacteriaceae. The pH was decreased in fecal samples from patients after BIB and SCFA profiles were altered, with lower percentages of acetate and propionate and higher levels of valerate and hexanoate. Some changes in the bacterial populations were associated with variations in the patients’ metabolic health parameters, namely Gemmiger and glucose, Lactobacillus and glucose, and Faecalibacterium and triglycerides. The results from this study of BIB patients furthers our understanding of the composition of gut microbiota and the functional changes that may be involved in improving obesity-related conditions following weight-loss surgery.

  14. Postoperative Changes in Fecal Bacterial Communities and Fermentation Products in Obese Patients Undergoing Bilio-Intestinal Bypass.

    Science.gov (United States)

    Patrone, Vania; Vajana, Elia; Minuti, Andrea; Callegari, Maria L; Federico, Alessandro; Loguercio, Carmela; Dallio, Marcello; Tolone, Salvatore; Docimo, Ludovico; Morelli, Lorenzo

    2016-01-01

    We assessed the gut microbial ecology of 11 severely obese patients before and after bilio-intestinal bypass (BIB). Fecal samples were evaluated for microbial communities using 16S rDNA Illumina sequencing, real-time PCR targeting functional genes, and gas chromatography of short chain fatty acids (SCFAs). At 6 months after surgery, subjects exhibited significant improvements in metabolic markers (body weight, glucose, and lipid metabolism) compared with baseline. The fecal microbiota of post-surgery individuals was characterized by an overall decrease of bacterial diversity, with a significant reduction in Lachnospiraceae, Clostridiaceae, Ruminococcaceae, Eubacteriaceae, and Coriobacteriaceae. On the contrary, there were significant increases of genera Lactobacillus, Megasphaera, and Acidaminococcus and the family Enterobacteriaceae. The pH was decreased in fecal samples from patients after BIB and SCFA profiles were altered, with lower percentages of acetate and propionate and higher levels of valerate and hexanoate. Some changes in the bacterial populations were associated with variations in the patients' metabolic health parameters, namely Gemmiger and glucose, Lactobacillus and glucose, and Faecalibacterium and triglycerides. The results from this study of BIB patients furthers our understanding of the composition of gut microbiota and the functional changes that may be involved in improving obesity-related conditions following weight-loss surgery. PMID:26941724

  15. SIV-induced Translocation of Bacterial Products in the Liver Mobilizes Myeloid Dendritic and Natural Killer Cells Associated With Liver Damage.

    Science.gov (United States)

    Evans, Tristan I; Li, Haiying; Schafer, Jamie L; Klatt, Nichole R; Hao, Xing-Pei; Traslavina, Ryan P; Estes, Jacob D; Brenchley, Jason M; Reeves, R Keith

    2016-02-01

    Disruption of the mucosal epithelium during lentivirus infections permits translocation of microbial products into circulation, causing immune activation and driving disease. Although the liver directly filters blood from the intestine and is the first line of defense against gut-derived antigens, the effects of microbial products on the liver are unclear. In livers of normal macaques, minute levels of bacterial products were detectable, but increased 20-fold in simian immunodeficiency virus (SIV)-infected animals. Increased microbial products in the liver induced production of the chemoattractant CXCL16 by myeloid dendritic cells (mDCs), causing subsequent recruitment of hypercytotoxic natural killer (NK) cells expressing the CXCL16 receptor, CXCR6. Microbial accumulation, mDC activation, and cytotoxic NK cell frequencies were significantly correlated with markers of liver damage, and SIV-infected animals consistently had evidence of hepatitis and fibrosis. Collectively, these data indicate that SIV-associated accumulation of microbial products in the liver initiates a cascade of innate immune activation, resulting in liver damage.

  16. Consumer-product attachment: measurement and design implications

    NARCIS (Netherlands)

    Schifferstein, H.N.J.; Zwartkruis-Pelgrim, E.P.H.

    2008-01-01

    Due to differences in the attachment consumers experience towards the durable products they own, they hang on to certain products whereas they easily dispose of others. From the viewpoint of sustainability, it may be worthwhile to lengthen the life span of many durable consumer products. Hence, ther

  17. Measuring Productive Efficiency: An Application to Illinois Strip Mines

    OpenAIRE

    P. Byrnes; R. Färe; S Grosskopf

    1984-01-01

    The purpose of this paper is to apply a generalized version of the Farrell measure of technical efficiency to a sample of Illinois strip mines. We disaggregate the original Farrell measure (which was designed to measure lost output or wasted inputs due to underutilization of inputs) into three mutually exclusive and exhaustive components: (1) a measure of purely technical efficiency, (2) a measure of input congestion (overutilization of some input(s)) and (3) a measure of scale efficiency. Th...

  18. Effects of dietary antibiotic growth promoter and Saccharomyces cerevisiae fermentation product on production, intestinal bacterial community, and nonspecific immunity of hybrid tilapia (Oreochromis niloticus female x Oreochromis aureus male).

    Science.gov (United States)

    He, S; Zhou, Z; Meng, K; Zhao, H; Yao, B; Ringø, E; Yoon, I

    2011-01-01

    To investigate the effects of a dietary antibiotic growth promoter (florfenicol) and a Saccharomyces cerevisiae fermentation product (DVAQUA) on growth, G:F, daily feed intake, intestinal bacterial community, and nonspecific immunity of hybrid tilapia (Oreochromis niloticus ♀ × Oreochromis aureus ♂), a 16-wk feeding trial was conducted in a recirculating aquaculture system. Four feeding regimens were evaluated: control, dietary florenicol (0.02 g/kg; 16 wk), dietary DVAQUA (0.5 g/kg; 16 wk), and sequential use of florenicol (0.02 g/kg; 8 wk), and DVAQUA (0.5 g/kg; 8 wk). Each regimen had 4 replicate tanks (0.5 × 0.5 × 0.5 m) and each tank contained 12 fish (initial BW: 46.88 ± 0.38 g). Dietary florfenicol improved growth (P = 0.089), G:F (P = 0.036), and serum complement component concentrations (P < 0.001) of hybrid tilapia. However, the compound decreased the estimated intestinal bacterial count estimated by rpoB quantitative PCR (P < 0.001) and bacterial diversity (visual band numbers, Shannon diversity index, and Shannon equitability index based on 16S rDNA V3 denaturing gradient gel electrophoresis fingerprints) compared with the control. Although sequential use of florfenicol and DVAQUA improved growth and G:F numerically to a similar extent as dietary florfenicol, and increased intestinal bacterial count to normal quantities, the sequential use of florenicol and DVAQUA decreased intestinal bacterial diversity (visual band numbers, Shannon diversity index, and Shannon equitability index) as well as serum complement component concentrations (P < 0.001) compared with their respective use and the control. These findings might be negatively related to disease control and host defense, and the sequential use of florenicol and DVAQUA should be practiced with caution. Feeding DAVQUA to the fish improved nonspecific immunity and increased intestinal bacterial count and bacterial diversity, but further research, including challenge studies, should be conducted

  19. Co-transcriptomic Analysis by RNA Sequencing to Simultaneously Measure Regulated Gene Expression in Host and Bacterial Pathogen

    KAUST Repository

    Ravasi, Timothy

    2016-01-24

    Intramacrophage pathogens subvert antimicrobial defence pathways using various mechanisms, including the targeting of host TLR-mediated transcriptional responses. Conversely, TLR-inducible host defence mechanisms subject intramacrophage pathogens to stress, thus altering pathogen gene expression programs. Important biological insights can thus be gained through the analysis of gene expression changes in both the host and the pathogen during an infection. Traditionally, research methods have involved the use of qPCR, microarrays and/or RNA sequencing to identify transcriptional changes in either the host or the pathogen. Here we describe the application of RNA sequencing using samples obtained from in vitro infection assays to simultaneously quantify both host and bacterial pathogen gene expression changes, as well as general approaches that can be undertaken to interpret the RNA sequencing data that is generated. These methods can be used to provide insights into host TLR-regulated transcriptional responses to microbial challenge, as well as pathogen subversion mechanisms against such responses.

  20. The efficacy of immediate versus delayed antibiotic administration on bacterial growth and biofilm production of selected strains of uropathogenic Escherichia coli and Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Leah Gandee

    2015-02-01

    Full Text Available Purpose The treatment of urinary tract infections (UTI with antibiotics is commonly used, but recurrence and antibiotic resistance have been growing and concerning clinicians. We studied whether the rapid onset of a protective biofilm may be responsible for the lack of effectiveness of antibiotics against selected bacteria. Materials and Methods Two established uropathogenic Escherichia coli strains, UTI89 and CFT073, and two Pseudomonas aeruginosa strains, PA01 and Boston-41501, were studied to establish a reliable biofilm formation process. Bacterial growth (BG was determined by optical density at 600 nm (OD 600 using a spectrophotometer, while biofilm formation (BF using crystal violet staining was measured at OD 550. Next, these bacterial strains were treated with clinically relevant antibiotics, ciprofloxacin HCl (200 ng/mL and 2 μg/mL, nitrofurantoin (20 μg/mL and 40 μg/mL and ampicillin (50 μg/mL at time points of 0 (T0 or after 6 hours of culture (T6. All measurements, including controls (bacteria -1% DMSO, were done in triplicates and repeated three times for consistency. Results The tested antibiotics effectively inhibited both BG and BF when administered at T0 for UPEC strains, but not when the antibiotic administration started 6 hours later. For Pseudomonas strains, only Ciprofloxacin was able to significantly inhibit bacterial growth at T0 but only at the higher concentration of 2 μg/mL for T6. Conclusion When established UPEC and Pseudomonas bacteria were allowed to culture for 6 hours before initialization of treatment, the therapeutic effect of selected antibiotics was greatly suppressed when compared to immediate treatment, probably as a result of the protective nature of the biofilm.

  1. Bacterial Vaginosis

    Science.gov (United States)

    ... 586. Related Content STDs during Pregnancy Fact Sheet Pregnancy and HIV, Viral Hepatitis, and STD Prevention Pelvic Inflammatory Disease ( ... Bacterial Vaginosis (BV) Chlamydia Gonorrhea Genital Herpes Hepatitis HIV/AIDS & STDs Human Papillomavirus ... STDs See Also Pregnancy Reproductive ...

  2. Bacterial Meningitis

    Science.gov (United States)

    ... Schedules Preteen & Teen Vaccines Meningococcal Disease Sepsis Bacterial Meningitis Recommend on Facebook Tweet Share Compartir On this ... serious disease. Laboratory Methods for the Diagnosis of Meningitis This manual summarizes laboratory methods used to isolate, ...

  3. Synthesis and Anti-Bacterial Activities of a Bis-Chalcone Derived from Thiophene and Its Bis-Cyclized Products

    Directory of Open Access Journals (Sweden)

    Abdullah M. Asiri

    2011-01-01

    Full Text Available A chalcone was prepared by the reaction of terephthalaldehyde with 3-acetyl-2,5-dimethylthiophene. Treatment of this chalcone with thiosemicarbazide/phenyl hydrazine/guanidine hydrochloride/thiourea afforded the corresponding pyrazoline,  pyrazole, and pyrimidine in good yields. All the new compounds have been characterized by IR, 1H-NMR, 13C-NMR, GC-MS and elemental analyses. The anti-bacterial activity of these compounds were first tested in vitro by the disk diffusion assay against two Gram-positive and two Gram-negative bacteria, and then the minimum inhibitory concentration (MIC was determined with the reference of standard drug chloramphenicol. The results showed that the pyrazoline derivative is better at inhibiting growth of both types of bacteria (Gram-positive and Gram-negative compared to chloramphenicol.

  4. Enhanced production of ε-caprolactone by coexpression of bacterial hemoglobin gene in recombinant Escherichia coli expressing cyclohexanone monooxygenase gene.

    Science.gov (United States)

    Lee, Won-Heong; Park, Eun-Hee; Kim, Myoung-Dong

    2014-12-28

    Baeyer-Villiger (BV) oxidation of cyclohexanone to epsilon-caprolactone in a microbial system expressing cyclohexanone monooxygenase (CHMO) can be influenced by not only the efficient regeneration of NADPH but also a sufficient supply of oxygen. In this study, the bacterial hemoglobin gene from Vitreoscilla stercoraria (vhb) was introduced into the recombinant Escherichia coli expressing CHMO to investigate the effects of an oxygen-carrying protein on microbial BV oxidation of cyclohexanone. Coexpression of Vhb allowed the recombinant E. coli strain to produce a maximum epsilon-caprolactone concentration of 15.7 g/l in a fed-batch BV oxidation of cyclohexanone, which corresponded to a 43% improvement compared with the control strain expressing CHMO only under the same conditions.

  5. The 'Sophistication' Of Exports: A New Measure Of Product Characteristics.

    OpenAIRE

    Lall, Sanjaya; Weiss, John; Zhang, Jinkang

    2005-01-01

    Trade data are often classified by product characteristics. We propose a new classification "sophistication" as a means of distinguishing between products. We construct a sophistication index based on the income levels of exporting economies. Sophistication captures a range of factors including technology, ease of product fragmentation, natural resource availability, and marketing. We calculate sophistication scores at the 3- and 4-digit levels and test how far the index relates to existing t...

  6. Measuring Product Type with Dynamics of Online Product Review Variances: A Theoretical Model and the Empirical Applications

    OpenAIRE

    Yili Hong; Pei-yu Chen; Lorin Hitt

    2014-01-01

    A significant body of literature in information systems, marketing, and economics has shown the important implication of the distinction between experience products and search products (“product type†) on consumer information search, marketplace design, and firm strategy. However, how to empirically measure product types remains a challenge, and this challenge is further complicated by the growth of online commerce and the increasing availability of online reviews that have transformed th...

  7. New lactic acid bacterial strains from traditional Mongolian fermented milk products have altered adhesion to porcine gastric mucin depending on the carbon source.

    Science.gov (United States)

    Kimoto-Nira, Hiromi; Yamasaki, Seishi; Sasaki, Keisuke; Moriya, Naoko; Takenaka, Akio; Suzuki, Chise

    2015-03-01

    Attachment of lactic acid bacteria to the mucosal surface of the gastrointestinal tract is a major property of probiotics. Here, we examined the ability of 21 lactic acid bacterial strains isolated from traditional fermented milk products in Mongolia to adhere to porcine gastric mucin in vitro. Higher attachment was observed with Lactobacillus delbrueckii subsp. bulgaricus strains 6-8 and 8-1 than with Lactobacillus rhamnosus GG (positive control). Lactococcus lactis subsp. cremoris strain 7-1 adhered to mucin as effectively as did strain GG. Heat inactivation decreased the adhesive ability of strains 6-8 and 8-1 but did not affect strain 7-1. The adhesion of strains 6-8, 7-1 and 8-1 was significantly inhibited when the cells were pretreated with periodate and trypsin, indicating that proteinaceous and carbohydrate-like cell surface compounds are involved in the adhesion of these strains. The adhesion of strain 7-1 was affected by the type of carbohydrate present in the growth medium, being higher with fructose than with lactose, galactose or xylose as the carbon source. The sugar content of 7-1 cells grown on various carbohydrates was negatively correlated with its adhesive ability. We provide new probiotic candidate strains and new information regarding carbohydrate preference that influences lactic acid bacterial adhesion to mucin.

  8. A natural bacterial-derived product, the metalloprotease arazyme, inhibits metastatic murine melanoma by inducing MMP-8 cross-reactive antibodies.

    Directory of Open Access Journals (Sweden)

    Felipe V Pereira

    Full Text Available The increased incidence, high rates of mortality and few effective means of treatment of malignant melanoma, stimulate the search for new anti-tumor agents and therapeutic targets to control this deadly metastatic disease. In the present work the antitumor effect of arazyme, a natural bacterial-derived metalloprotease secreted by Serratia proteomaculans, was investigated. Arazyme significantly reduced the number of pulmonary metastatic nodules after intravenous inoculation of B16F10 melanoma cells in syngeneic mice. In vitro, the enzyme showed a dose-dependent cytostatic effect in human and murine tumor cells, and this effect was associated to the proteolytic activity of arazyme, reducing the CD44 expression at the cell surface, and also reducing in vitro adhesion and in vitro/in vivo invasion of these cells. Arazyme treatment or immunization induced the production of protease-specific IgG that cross-reacted with melanoma MMP-8. In vitro, this antibody was cytotoxic to tumor cells, an effect increased by complement. In vivo, arazyme-specific IgG inhibited melanoma lung metastasis. We suggest that the antitumor activity of arazyme in a preclinical model may be due to a direct cytostatic activity of the protease in combination with the elicited anti-protease antibody, which cross-reacts with MMP-8 produced by tumor cells. Our results show that the bacterial metalloprotease arazyme is a promising novel antitumor chemotherapeutic agent.

  9. A Natural Bacterial-Derived Product, the Metalloprotease Arazyme, Inhibits Metastatic Murine Melanoma by Inducing MMP-8 Cross-Reactive Antibodies

    Science.gov (United States)

    Pereira, Felipe V.; Ferreira-Guimarães, Carla A.; Paschoalin, Thaysa; Scutti, Jorge A. B.; Melo, Filipe M.; Silva, Luis S.; Melo, Amanda C. L.; Silva, Priscila; Tiago, Manoela; Matsuo, Alisson L.; Juliano, Luiz; Juliano, Maria A.; Carmona, Adriana K.; Travassos, Luiz R.; Rodrigues, Elaine G.

    2014-01-01

    The increased incidence, high rates of mortality and few effective means of treatment of malignant melanoma, stimulate the search for new anti-tumor agents and therapeutic targets to control this deadly metastatic disease. In the present work the antitumor effect of arazyme, a natural bacterial-derived metalloprotease secreted by Serratia proteomaculans, was investigated. Arazyme significantly reduced the number of pulmonary metastatic nodules after intravenous inoculation of B16F10 melanoma cells in syngeneic mice. In vitro, the enzyme showed a dose-dependent cytostatic effect in human and murine tumor cells, and this effect was associated to the proteolytic activity of arazyme, reducing the CD44 expression at the cell surface, and also reducing in vitro adhesion and in vitro/in vivo invasion of these cells. Arazyme treatment or immunization induced the production of protease-specific IgG that cross-reacted with melanoma MMP-8. In vitro, this antibody was cytotoxic to tumor cells, an effect increased by complement. In vivo, arazyme-specific IgG inhibited melanoma lung metastasis. We suggest that the antitumor activity of arazyme in a preclinical model may be due to a direct cytostatic activity of the protease in combination with the elicited anti-protease antibody, which cross-reacts with MMP-8 produced by tumor cells. Our results show that the bacterial metalloprotease arazyme is a promising novel antitumor chemotherapeutic agent. PMID:24788523

  10. Microbial production of xylitol from xylose and L-arabinose: conversion of L-arabitol to xylitol using bacterial oxidoreductases

    Science.gov (United States)

    Microbial production of xylitol, using hemicellulosic biomass such as agricultural residues, is becoming more attractive for reducing its manufacturing cost. L-arabitol is a particular problem to xylitol production from hemicellulosic hydrolyzates that contain both xylose and L-arabinose because it...

  11. Measuring the "Ideas" Production Function: Evidence from International Patent Output

    OpenAIRE

    Porter, Michael E.; Scott Stern

    2000-01-01

    This paper estimates the parameters of the ideas' production function central to recent models of economic growth. We do so by evaluating the determinants of international' patenting rates across the OECD, where an international patent is one granted by the U.S. patent office to a foreign establishment. Taking advantage of variation in the flow of ideas produced by different countries over time, we provide evidence for three main findings. First, at the level of the production of internationa...

  12. Measuring the Canada-U.S. Productivity Gap: Industry Dimensions

    OpenAIRE

    Someshwar Rao; Jianmin Tang; Weimin Wang

    2004-01-01

    A key objective of economic policy in Canada is to reduce the productivity gap with the United States. The development of appropriate policies to attain this goal requires a thorough understanding of the nature of the gap, including its industry dimensions. Unfortunately, statistical agencies do not currently produce estimates of Canada-U.S. productivity gaps by industry. To fill this data lacuna, Someshwar Rao, Jianmin Tang, and Weimin Wang of Industry Canada in the first article present ben...

  13. Productivity in the Mining Industry: Measurement and Interpretation

    OpenAIRE

    Vernon Topp; Leo Soames; Dean Parham; Harry Bloch

    2008-01-01

    Mining typically accounts for around 5 per cent of Australia's nominal market sector gross domestic product. Long lead times between investment in new capacity in mining and the associated output response can lead to short term movements in mining multifactor productivity (MFP) unrelated to underlying efficiency. Ongoing depletion of Australia's natural resource base is estimated to have had a significant adverse effect on long-term mining MFP. Over the longer-term, MFP impacts of resource de...

  14. Characterization of foot-and-mouth disease virus gene products with antisera against bacterially synthesized fusion proteins

    International Nuclear Information System (INIS)

    Defined segments of the cloned foot-and-mouth disease virus genome corresponding to all parts of the coding region were expressed in Escherichia coli as fusions to the N-terminal part of the MS2-polymerase gene under the control of the inducible λPL promoter. All constructs yielded large amounts of proteins, which were purified and used to raise sequence-specific antisera in rabbits. These antisera were used to identify the corresponding viral gene products in 35S-labeled extracts from foot-and-mouth disease virus-infected BHK cells. This allowed us to locate unequivocally all mature foot-and-mouth disease virus gene products in the nucleotide sequence, to identify precursor-product relationships, and to detect several foot-and mouth disease virus gene products not previously identified in vivo or in vitro

  15. A Versatile Strategy for Production of Membrane Proteins with Diverse Topologies: Application to Investigation of Bacterial Homologues of Human Divalent Metal Ion and Nucleoside Transporters.

    Science.gov (United States)

    Ma, Cheng; Hao, Zhenyu; Huysmans, Gerard; Lesiuk, Amelia; Bullough, Per; Wang, Yingying; Bartlam, Mark; Phillips, Simon E; Young, James D; Goldman, Adrian; Baldwin, Stephen A; Postis, Vincent L G

    2015-01-01

    Membrane proteins play key roles in many biological processes, from acquisition of nutrients to neurotransmission, and are targets for more than 50% of current therapeutic drugs. However, their investigation is hampered by difficulties in their production and purification on a scale suitable for structural studies. In particular, the nature and location of affinity tags introduced for the purification of recombinant membrane proteins can greatly influence their expression levels by affecting their membrane insertion. The extent of such effects typically depends on the transmembrane topologies of the proteins, which for proteins of unknown structure are usually uncertain. For example, attachment of oligohistidine tags to the periplasmic termini of membrane proteins often interferes with folding and drastically impairs expression in Escherichia coli. To circumvent this problem we have employed a novel strategy to enable the rapid production of constructs bearing a range of different affinity tags compatible with either cytoplasmic or periplasmic attachment. Tags include conventional oligohistidine tags compatible with cytoplasmic attachment and, for attachment to proteins with a periplasmic terminus, either tandem Strep-tag II sequences or oligohistidine tags fused to maltose binding protein and a signal sequence. Inclusion of cleavage sites for TEV or HRV-3C protease enables tag removal prior to crystallisation trials or a second step of purification. Together with the use of bioinformatic approaches to identify members of membrane protein families with topologies favourable to cytoplasmic tagging, this has enabled us to express and purify multiple bacterial membrane transporters. To illustrate this strategy, we describe here its use to purify bacterial homologues of human membrane proteins from the Nramp and ZIP families of divalent metal cation transporters and from the concentrative nucleoside transporter family. The proteins are expressed in E. coli in a

  16. Accredited dose measurements for validation of radiation sterilized products

    DEFF Research Database (Denmark)

    Miller, A.

    1993-01-01

    for control of radiation sterilization. The accredited services include: 1. 1. Irradiation of dosimeters and test samples with cobalt-60 gamma rays. 2. 2. Irradiation of dosimeters and test samples with 10 MeV electrons. 3. 3. Issue of and measurement with calibrated dosimeters. 4. 4. Measurement...

  17. Measurements of photon and jet production properties with CMS

    CERN Document Server

    Flouris, Giannis

    2016-01-01

    The measurements of the jet charge, the Z+jet and gamma+jet, the dijet azimuthal decorrelations, and the inclusive jet cross sections are presented. The measurements use the samples of proton-proton collisions collected with the CMS detector at the LHC at a center-of-mass energy of 8 and 13 TeV.

  18. Measurement of Inclusive W and Z Production in ATLAS

    Directory of Open Access Journals (Sweden)

    Goddard J. R.

    2013-11-01

    Full Text Available A summary of five ATLAS W and Z inclusive measurements are presented, these are a mixture of analyses using the 2010 and 2011 datasets of √s = 7 TeV proton-proton collisions at the LHC. The 2010 data is used to measure the cross sections of the Z, W+ and W.. bosons which are then used with the HERA deep inelastic scattering data to determine the strange quark density of the proton. Three analyses that use 2011 data are shown; a measurement of the forward-backward asymmetry of the Z/γ* boson, from which the effective weak mixing angle is extracted; a measurement of the angular correlations of Drell-Yan lepton pairs from resonant Z decays; and a measurement of the high mass Drell-Yan differential cross section.

  19. Measurement of Inclusive W and Z Production in ATLAS

    CERN Document Server

    Goddard, J R

    2013-01-01

    A summary of five ATLAS $W$ and $Z$ inclusive measurements are presented, these are a mixture of analyses using the 2010 and 2011 datasets of $\\sqrt{s}=7$ TeV proton-proton collisions at the LHC. The 2010 data is used to measure the cross sections of the $Z$, $W^{+}$ and $W^{-}$ bosons which are then used with the HERA deep inelastic scattering data to determine the strange quark density of the proton. Three analyses that use 2011 data are shown; a measurement of the forward-backward asymmetry of the $Z/\\gamma^{*}$ boson, from which the effective weak mixing angle is extracted; a measurement of the angular correlations of Drell-Yan lepton pairs from resonant $Z$ decays; and a measurement of the high mass Drell-Yan differential cross section.

  20. Temperature and Light Effects on Extracellular Superoxide Production by Algal and Bacterial Symbionts in Corals: Implications for Coral Bleaching

    Science.gov (United States)

    Brighi, C.; Diaz, J. M.; Apprill, A.; Hansel, C. M.

    2014-12-01

    Increased surface seawater temperature due to global warming is one of the main causes of coral bleaching, a phenomenon in which corals lose their photosynthetic algae. Light and temperature induced production of superoxide and other reactive oxygen species (ROS) by these symbiotic algae has been implicated in the breakdown of their symbiotic association with the coral host and subsequent coral bleaching. Nevertheless, a direct link between Symbiodinium ROS production and coral bleaching has not been demonstrated. In fact, given the abundance and diversity of microorganisms within the coral holobiont, the concentration and fluxes of ROS within corals may involve several microbial sources and sinks. Here, we explore the role of increased light and temperature on superoxide production by coral-derived cultures of Symbiodinium algae and Oceanospirillales bacteria of the genus Endozoicomonas, which are globally common and abundant associates of corals. Using a high sensitivity chemiluminescent technique, we find that heat stress (exposure to 34°C vs. 23°C for 2hr or 24hr) has no significant effect on extracellular superoxide production by Symbiodinium isolates within clades B and C, regardless of the level of light exposure. Exposure to high light, however, increased superoxide production by these organisms at both 34°C and 23°C. On the other hand, extracellular superoxide production by Endozoicomonas bacteria tested under the same conditions was stimulated by the combined effects of thermal and light stress. The results of this research suggest that the sources and physical triggers for biological superoxide production within corals are more complex than currently assumed. Thus, further investigations into the biological processes controlling ROS dynamics within corals are required to improve our understanding of the mechanisms underpinning coral bleaching and to aid in the development of mitigation strategies.