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Sample records for evaporite microbial films

  1. EVAPORITE MICROBIAL FILMS, MATS, MICROBIALITES AND STROMATOLITES

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    Brigmon, R; Penny Morris, P; Garriet Smith, G

    2008-01-28

    Evaporitic environments are found in a variety of depositional environments as early as the Archean. The depositional settings, microbial community and mineralogical composition vary significantly as no two settings are identical. The common thread linking all of the settings is that evaporation exceeds precipitation resulting in elevated concentrations of cations and anions that are higher than in oceanic systems. The Dead Sea and Storrs Lake are examples of two diverse modern evaporitic settings as the former is below sea level and the latter is a coastal lake on an island in the Caribbean. Each system varies in water chemistry as the Dead Sea dissolved ions originate from surface weathered materials, springs, and aquifers while Storrs Lake dissolved ion concentration is primarily derived from sea water. Consequently some of the ions, i.e., Sr, Ba are found at significantly lower concentrations in Storrs Lake than in the Dead Sea. The origin of the dissolved ions are ultimately responsible for the pH of each system, alkaline versus mildly acidic. Each system exhibits unique biogeochemical properties as the extreme environments select certain microorganisms. Storrs Lake possesses significant biofilms and stromatolitic deposits and the alkalinity varies depending on rainfall and storm activity. The microbial community Storrs Lake is much more diverse and active than those observed in the Dead Sea. The Dead Sea waters are mildly acidic, lack stromatolites, and possess a lower density of microbial populations. The general absence of microbial and biofilm fossilization is due to the depletion of HCO{sub 3} and slightly acidic pH.

  2. Microbial Diversity in Sediment Ecosystems (Evaporites Domes, Microbial Mats, and Crusts) of Hypersaline Laguna Tebenquiche, Salar de Atacama, Chile.

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    Fernandez, Ana B; Rasuk, Maria C; Visscher, Pieter T; Contreras, Manuel; Novoa, Fernando; Poire, Daniel G; Patterson, Molly M; Ventosa, Antonio; Farias, Maria E

    2016-01-01

    We combined nucleic acid-based molecular methods, biogeochemical measurements, and physicochemical characteristics to investigate microbial sedimentary ecosystems of Laguna Tebenquiche, Atacama Desert, Chile. Molecular diversity, and biogeochemistry of hypersaline microbial mats, rhizome-associated concretions, and an endoevaporite were compared with: The V4 hypervariable region of the 16S rRNA gene was amplified by pyrosequencing to analyze the total microbial diversity (i.e., bacteria and archaea) in bulk samples, and in addition, in detail on a millimeter scale in one microbial mat and in one evaporite. Archaea were more abundant than bacteria. Euryarchaeota was one of the most abundant phyla in all samples, and particularly dominant (97% of total diversity) in the most lithified ecosystem, the evaporite. Most of the euryarchaeal OTUs could be assigned to the class Halobacteria or anaerobic and methanogenic archaea. Planctomycetes potentially also play a key role in mats and rhizome-associated concretions, notably the aerobic organoheterotroph members of the class Phycisphaerae. In addition to cyanobacteria, members of Chromatiales and possibly the candidate family Chlorotrichaceae contributed to photosynthetic carbon fixation. Other abundant uncultured taxa such as the candidate division MSBL1, the uncultured MBGB, and the phylum Acetothermia potentially play an important metabolic role in these ecosystems. Lithifying microbial mats contained calcium carbonate precipitates, whereas endoevoporites consisted of gypsum, and halite. Biogeochemical measurements revealed that based on depth profiles of O2 and sulfide, metabolic activities were much higher in the non-lithifying mat (peaking in the least lithified systems) than in lithifying mats with the lowest activity in endoevaporites. This trend in decreasing microbial activity reflects the increase in salinity, which may play an important role in the biodiversity.

  3. Microbial diversity in sediment ecosystems (evaporites domes, microbial mats and crusts of hypersaline Laguna Tebenquiche, Salar de Atacama, Chile

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    Ana Beatriz Fernandez

    2016-08-01

    Full Text Available We combined nucleic acid-based molecular methods, biogeochemical measurements and physicochemical characteristics to investigate microbial sedimentary ecosystems of Laguna Tebenquiche, Atacama Desert, Chile. Molecular diversity and biogeochemistry of hypersaline microbial mats, rhizome-associated concretions and an endoevaporite were compared with: The V4 hypervariable region of the 16S rRNA gene was amplified by pyrosequencing to analyze the total microbial diversity (i.e., bacteria and archaea in bulk samples and, in addition, in detail on a millimeter scale in one microbial mat and in one evaporite. Archaea were more abundant than bacteria. Euryarchaeota was one of the most abundant phyla in all samples, and particularly dominant (97% of total diversity in the most lithified ecosystem, the evaporite. Most of the euryarchaeal OTUs could be assigned to the class Halobacteria or anaerobic and methanogenic archaea. Planctomycetes potentially also play a key role in mats and rhizome-associated concretions, notably the aerobic organoheterotroph members of the class Phycisphaerae. In addition to cyanobacteria, members of Chromatiales and possibly the candidate family Chlorotrichaceae contributed to photosynthetic carbon fixation. Other abundant uncultured taxa such as the candidate division MSBL1, the uncultured MBGB and the phylum Acetothermia potentially play an important metabolic role in these ecosystems. Lithifying microbial mats contained calcium carbonate precipitates, whereas endoevoporites consisted of gypsum and halite. Biogeochemical measurements revealed that based on depth profiles of O2 and sulfide, metabolic activities were much higher in the non-lithifying mat (peaking in the least lithified systems than in lithifying mats with the lowest activity in endoevaporites. This trend in decreasing microbial activity reflects the increase in salinity, which may play an important role in the biodiversity.

  4. Microbial Diversity in Sediment Ecosystems (Evaporites Domes, Microbial Mats, and Crusts) of Hypersaline Laguna Tebenquiche, Salar de Atacama, Chile

    Science.gov (United States)

    Fernandez, Ana B.; Rasuk, Maria C.; Visscher, Pieter T.; Contreras, Manuel; Novoa, Fernando; Poire, Daniel G.; Patterson, Molly M.; Ventosa, Antonio; Farias, Maria E.

    2016-01-01

    We combined nucleic acid-based molecular methods, biogeochemical measurements, and physicochemical characteristics to investigate microbial sedimentary ecosystems of Laguna Tebenquiche, Atacama Desert, Chile. Molecular diversity, and biogeochemistry of hypersaline microbial mats, rhizome-associated concretions, and an endoevaporite were compared with: The V4 hypervariable region of the 16S rRNA gene was amplified by pyrosequencing to analyze the total microbial diversity (i.e., bacteria and archaea) in bulk samples, and in addition, in detail on a millimeter scale in one microbial mat and in one evaporite. Archaea were more abundant than bacteria. Euryarchaeota was one of the most abundant phyla in all samples, and particularly dominant (97% of total diversity) in the most lithified ecosystem, the evaporite. Most of the euryarchaeal OTUs could be assigned to the class Halobacteria or anaerobic and methanogenic archaea. Planctomycetes potentially also play a key role in mats and rhizome-associated concretions, notably the aerobic organoheterotroph members of the class Phycisphaerae. In addition to cyanobacteria, members of Chromatiales and possibly the candidate family Chlorotrichaceae contributed to photosynthetic carbon fixation. Other abundant uncultured taxa such as the candidate division MSBL1, the uncultured MBGB, and the phylum Acetothermia potentially play an important metabolic role in these ecosystems. Lithifying microbial mats contained calcium carbonate precipitates, whereas endoevoporites consisted of gypsum, and halite. Biogeochemical measurements revealed that based on depth profiles of O2 and sulfide, metabolic activities were much higher in the non-lithifying mat (peaking in the least lithified systems) than in lithifying mats with the lowest activity in endoevaporites. This trend in decreasing microbial activity reflects the increase in salinity, which may play an important role in the biodiversity. PMID:27597845

  5. Microbial characterization of microbial ecosystems associated to evaporites domes of gypsum in Salar de Llamara in Atacama desert.

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    Rasuk, Maria Cecilia; Kurth, Daniel; Flores, Maria Regina; Contreras, Manuel; Novoa, Fernando; Poire, Daniel; Farias, Maria Eugenia

    2014-10-01

    The Central Andes in northern Chile contains a large number of closed basins whose central depression is occupied by saline lakes and salt crusts (salars). One of these basins is Salar de Llamara (850 m a.s.l.), where large domed structures of seemingly evaporitic origin forming domes can be found. In this work, we performed a detailed microbial characterization of these domes. Mineralogical studies revealed gypsum (CaSO(4)) as a major component. Microbial communities associated to these structures were analysed by 454 16S rDNA amplicon sequencing and compared between winter and summer seasons. Bacteroidetes Proteobacteria and Planctomycetes remained as the main phylogenetic groups, an increased diversity was found in winter. Comparison of the upper air-exposed part and the lower water-submerged part of the domes in both seasons showed little variation in the upper zone, showing a predominance of Chromatiales (Gammaproteobacteria), Rhodospirillales (Alphaproteobacteria), and Sphingobacteriales (Bacteroidetes). However, the submerged part showed marked differences between seasons, being dominated by Proteobacteria (Alpha and Gamma) and Verrucomicrobia in summer, but with more diverse phyla found in winter. Even though not abundant by sequence, Cyanobacteria were visually identified by scanning electron microscopy (SEM), which also revealed the presence of diatoms. Photosynthetic pigments were detected by high-performance liquid chromatography, being more diverse on the upper photosynthetic layer. Finally, the system was compared with other endoevaporite, mats microbialite and Stromatolites microbial ecosystems, showing higher similitude with evaporitic ecosystems from Atacama and Guerrero Negro. This environment is of special interest for extremophile studies because microbial life develops associated to minerals in the driest desert all over the world. Nevertheless, it is endangered by mining activity associated to copper and lithium extraction; thus, its

  6. Nutrient Stoichiometry Shapes Microbial Community Structure in an Evaporitic Shallow Pond

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    Zarraz M.-P. Lee

    2017-05-01

    Full Text Available Nutrient availability and ratios can play an important role in shaping microbial communities of freshwater ecosystems. The Cuatro Ciénegas Basin (CCB in Mexico is a desert oasis where, perhaps paradoxically, high microbial diversity coincides with extreme oligotrophy. To better understand the effects of nutrients on microbial communities in CCB, a mesocosm experiment was implemented in a stoichiometrically imbalanced pond, Lagunita, which has an average TN:TP ratio of 122 (atomic. The experiment had four treatments, each with five spatial replicates – unamended controls and three fertilization treatments with different nitrogen:phosphorus (N:P regimes (P only, N:P = 16 and N:P = 75 by atoms. In the water column, quantitative PCR of the 16S rRNA gene indicated that P enrichment alone favored proliferation of bacterial taxa with high rRNA gene copy number, consistent with a previously hypothesized but untested connection between rRNA gene copy number and P requirement. Bacterial and microbial eukaryotic community structure was investigated by pyrosequencing of 16S and 18S rRNA genes from the planktonic and surficial sediment samples. Nutrient enrichment shifted the composition of the planktonic community in a treatment-specific manner and promoted the growth of previously rare bacterial taxa at the expense of the more abundant, potentially endemic, taxa. The eukaryotic community was highly enriched with phototrophic populations in the fertilized treatment. The sediment microbial community exhibited high beta diversity among replicates within treatments, which obscured any changes due to fertilization. Overall, these results showed that nutrient stoichiometry can be an important factor in shaping microbial community structure.

  7. Nutrient Stoichiometry Shapes Microbial Community Structure in an Evaporitic Shallow Pond.

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    Lee, Zarraz M-P; Poret-Peterson, Amisha T; Siefert, Janet L; Kaul, Drishti; Moustafa, Ahmed; Allen, Andrew E; Dupont, Chris L; Eguiarte, Luis E; Souza, Valeria; Elser, James J

    2017-01-01

    Nutrient availability and ratios can play an important role in shaping microbial communities of freshwater ecosystems. The Cuatro Ciénegas Basin (CCB) in Mexico is a desert oasis where, perhaps paradoxically, high microbial diversity coincides with extreme oligotrophy. To better understand the effects of nutrients on microbial communities in CCB, a mesocosm experiment was implemented in a stoichiometrically imbalanced pond, Lagunita, which has an average TN:TP ratio of 122 (atomic). The experiment had four treatments, each with five spatial replicates - unamended controls and three fertilization treatments with different nitrogen:phosphorus (N:P) regimes (P only, N:P = 16 and N:P = 75 by atoms). In the water column, quantitative PCR of the 16S rRNA gene indicated that P enrichment alone favored proliferation of bacterial taxa with high rRNA gene copy number, consistent with a previously hypothesized but untested connection between rRNA gene copy number and P requirement. Bacterial and microbial eukaryotic community structure was investigated by pyrosequencing of 16S and 18S rRNA genes from the planktonic and surficial sediment samples. Nutrient enrichment shifted the composition of the planktonic community in a treatment-specific manner and promoted the growth of previously rare bacterial taxa at the expense of the more abundant, potentially endemic, taxa. The eukaryotic community was highly enriched with phototrophic populations in the fertilized treatment. The sediment microbial community exhibited high beta diversity among replicates within treatments, which obscured any changes due to fertilization. Overall, these results showed that nutrient stoichiometry can be an important factor in shaping microbial community structure.

  8. Microbial diversity in sediment ecosystems (evaporites domes, microbial mats and crusts) of hypersaline Laguna Tebenquiche, Salar de Atacama, Chile

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    Ana Beatriz Fernandez; Maria Cecilia Rasuk; Visscher, Pieter T.; Manuel Contreras; Fernando Novoa; Daniel Poire; Patterson, Molly M.; Antonio Ventosa; Maria Eugenia Farias

    2016-01-01

    We combined nucleic acid-based molecular methods, biogeochemical measurements and physicochemical characteristics to investigate microbial sedimentary ecosystems of Laguna Tebenquiche, Atacama Desert, Chile. Molecular diversity and biogeochemistry of hypersaline microbial mats, rhizome-associated concretions and an endoevaporite were compared with: The V4 hypervariable region of the 16S rRNA gene was amplified by pyrosequencing to analyze the total microbial diversity (i.e., bacteria and arch...

  9. Terrestrial Evaporite Analogues for Identifying Extremophiles (Past or Present) from Potential Mars Evaporites

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    Morris, P.; Wentworth, S.; Byrne, M.; Nelman, M.; Longazo, T.; Allen, C.; Brigmon, R.; McKay, D.

    An understanding of terrestrial evaporite microbial biota, their markers and fossilization processes is important for identifying potential present or past life signs from extraterrestrial sources such as Mars meteorites and Mars sample return. Storrs Lake, San Salvador Island, Bahamas, Mono Lake, California and the Dead Sea, Israel represent marine and nonmarine sites for comparative investigative studies of potential Mars analogues. Variations between the sites can be attributed to salinity, pH, water chemistry, and seasonal temperature changes, all of which can affect microbial abundance, fossilization, and mineral formation. Storr's Lake, located at sea level, pH 8, salinity averaging 7 g/l. has extensive stromatolitic structures0 composed of biofilm, rods, filaments, cocci and diatoms. The fossilized organic remains are generally composed of magnesium enriched calcium carbonate. Mono Lake is 2100 meters above sea level, pH and salinity are similar to Storr's Lake, and it has various evaporite and carbonate deposits including tufa structures that vary in height from less than 1 meter to over 4 meters. Algae, cyanobacteria, diatoms, and other microbial forms are present and contribute to t e formation of evaporiteh deposits including tufas. The Dead Sea is 400 m below sea level, pH 6.3 in the upper water mass, salinity averaging 229.9 g/l, and possesses extensive salt deposits with scant evidence of microbial fossilization as large carbonate structures such as tufas and stromatolites are absent. Modern investigative tools can identify microbes from all of these environments, but confirming the presence of fossilized microbes and their biomarkers subsequent to burial and lithification is more difficult. The goal of this study is to identify these biomarkers and test their suitability for identifying extraterrestrial microbial remains.

  10. Physical properties of evaporite minerals

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    Robertson, Eugene C.

    1962-01-01

    The data in the following tables were abstracted from measurements of physical properties of evaporite minerals or of equivalent synthetic compounds. The compounds considered are the halide and sulfate salts which supposedly precipitated from evaporating ocean water and which form very extensive and thick "rock salt" beds. These beds are composed almost entirely of NaCl. In places where the beds are deeply buried and where fractures occur in the overlying rocks, the salt is plastically extruded upward as in a pipe to form the "salt domes". Most of the tables are for NaCl, both the natural (halite) and the synthetic salt, polycrystalline and single crystals. These measurements have been collected for use 1) in studies on storage of radioactive wastes in salt domes or beds, 2) in calculations concerned with nuclear tests in salt domes and beds, and 3) in studies of phenomena in salt of geologic interest. Rather than an exhaustive compilation of physical property measurements, there tables represent a summary of data from accessible sources. As limitations of time have presented making a more systematic and comprehensive selection, the data given may seem arbitrarily chosen. Some of the data listed are old, and newer, more accurate data are undoubtedly available. Halite (an synthetic NaCl) has been very thoroughly studied because of its relatively simple and highly symmetrical crystal structure, its easy availability naturally or synthetically, both in single crystals and polycrystalline, its useful and scientifically interesting properties, and its role as a compound of almost purely ionic bonding. The measurements of NaCl in the tables, however, represent only a small part of the total number of observations; discrimination was necessary to keep the size of the tabulations manageable. The physical properties of the evaporite minerals other than halite and sylvite have received only desultory attention of experiementalists, and appear in only a few tables. The

  11. Evaporitic minibasins of the Sivas Basin (Turkey)

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    Pichat, Alexandre; Hoareau, Guilhem; Callot, Jean-Paul; Ringenbach, Jean-Claude; Kavak, Kaan

    2017-04-01

    The Oligo-Miocene Sivas basin (Turkey) was strongly affected by salt tectonics, best expressed in its central part. Halokinesis initiated from a main evaporite layer deposited during the Upper Eocene. Such evaporitic accumulations led to two generations of mini basins filled with continental to marine deposits, and nowadays separated by diapiric gypsum walls or welds. Some mini-basins developed above depleting diapirs, filled by more than 50 % of lacustrine to sebkhaic gypsiferous facies. These evaporitic mini-basins (EMB) developed during periods of limited fluvial input, when diapiric stems were outcropping with insignificant topographic reliefs. Chemical analyses (S, O and Sr) suggest that such evaporites were sourced from the recycling of adjacent salt structures. EMB development above diapirs can be explained by (i) high regional accommodation (Ribes et al., 2016), (ii) erosion of the diapiric crests by the fluvial system preceding evaporite deposition, (iii) deflation of some diapirs in a transtensive setting (Kergaravat, 2015), and (iv) fast sedimentation rate of the evaporites. EMB stand out from other siliciclastic mini-basins of the Sivas Basin by (i) their small dimension (< 1km), (ii) their teardrop encased shape and (iii) exacerbated internal halokinetic deformations. The latter specifically include large halokinetic wedges, mega-slumps or inverted mega-flaps. Comparison with siliciclastic mini-basins suggests that strong halokinesis of EMB was triggered by the ductile rheology of their evaporitic infilling. Additional filling and subsequent withdrawal of EMB may have been also increased by (i) the large amount of solutes provided by leaching of the outcropping diapiric structure together with the fast sedimentation rate of the evaporites and (iii) the high density of the gypsum and anhydrite compared to halite. The Great Kavir in Iran could display present day analogues relevant of early-stage EMB. Finally, although EMB have never been identified in

  12. Microbial colonization of biopolymeric thin films containing natural compounds and antibiotics fabricated by MAPLE

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    Cristescu, R.; Surdu, A. V.; Grumezescu, A. M.; Oprea, A. E.; Trusca, R.; Vasile, O.; Dorcioman, G.; Visan, A.; Socol, G.; Mihailescu, I. N.; Mihaiescu, D.; Enculescu, M.; Chifiriuc, M. C.; Boehm, R. D.; Narayan, R. J.; Chrisey, D. B.

    2015-05-01

    Although a great number of antibiotics are currently available, they are often rendered ineffective by the ability of microbial strains to develop genetic resistance and to grow in biofilms. Since many antimicrobial agents poorly penetrate biofilms, biofilm-associated infections often require high concentrations of antimicrobial agents for effective treatment. Among the various strategies that may be used to inhibit microbial biofilms, one strategy that has generated significant interest involves the use of bioactive surfaces that are resistant to microbial colonization. In this respect, we used matrix assisted pulsed laser evaporation (MAPLE) involving a pulsed KrF* excimer laser source (λ = 248 nm, τ = 25 ns, ν = 10 Hz) to obtain thin composite biopolymeric films containing natural (flavonoid) or synthetic (antibiotic) compounds as bioactive substances. Chemical composition and film structures were investigated by Fourier transform infrared spectroscopy and X-ray diffraction. Films morphology was studied by scanning electron microscopy and transmission electron microscopy. The antimicrobial assay of the microbial biofilms formed on these films was assessed by the viable cell counts method. The flavonoid-containing thin films showed increased resistance to microbial colonization, highlighting their potential to be used for the design of anti-biofilm surfaces.

  13. Evaporite karst in Italy: a review

    National Research Council Canada - National Science Library

    Jo De Waele; Leonardo Piccini; Andrea Columbu; Giuliana Madonia; Marco Vattano; Chiara Calligaris; Ilenia M D'Angeli; Mario Parise; Mauro Chiesi; Michele Sivelli; Bartolomeo Vigna; Luca Zini; Veronica Chiarini; Francesco Sauro; Russell Drysdale; Paolo Forti

    2017-01-01

    .... More recent and detailed studies focused on the gypsum areas of Emilia-Romagna and Sicily. Sinkholes related to Permian-Triassic gypsum have been studied in Friuli Venezia Giulia. This article reviews the state of the art regarding different aspects of evaporite karst in Italy focusing on the main new results.

  14. Microbial colonization of biopolymeric thin films containing natural compounds and antibiotics fabricated by MAPLE

    Energy Technology Data Exchange (ETDEWEB)

    Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, PO Box MG-36, Bucharest-Magurele (Romania); Surdu, A.V.; Grumezescu, A.M.; Oprea, A.E.; Trusca, R.; Vasile, O. [Faculty of Applied Chemistry and Materials Science, Department of Science and Engineering of Oxide Materials and Nanomaterials, Politehnica University of Bucharest, Polizu Street No. 1–7, 011061 Bucharest (Romania); Dorcioman, G.; Visan, A.; Socol, G.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, PO Box MG-36, Bucharest-Magurele (Romania); Mihaiescu, D. [Faculty of Applied Chemistry and Materials Science, Department of Organic Chemistry, Politehnica University of Bucharest, 1–7 Polizu Street, 011061 Bucharest (Romania); Enculescu, M. [National Institute of Materials Physics, PO Box MG-7, Bucharest-Magurele (Romania); Chifiriuc, M.C. [Microbiology Immunology Department, Faculty of Biology, Research Institute of the University of Bucharest—ICUB, Research Institute of the University of Bucharest, 77206 Bucharest (Romania); Boehm, R.D.; Narayan, R.J. [Biomedical Engineering, University of North Carolina, Chapel Hill, NC (United States); Chrisey, D.B. [Department of Physics and Engineering Physics, Tulane University, New Orleans, LA (United States)

    2015-05-01

    Highlights: • We deposited thin composite quercetin/polyvinylpyrrolidone/antibiotic films with close resemblance to the starting/drop-cast composition by MAPLE. • Quercetin flavonoid shows an anti-biofilm activity comparable to that of the tested large-spectrum antibiotics (norfloxacin or cefuroxime), especially in case of 72 h biofilms. • These results could account for the possible use of quercetin as an alternative to antibiotics to combat the mature biofilms developed on different substrates. • MAPLE may be used to produce implantable medical devices that provide a relatively long term in vitro stability and resistance to the growth of microorganisms. - Abstract: Although a great number of antibiotics are currently available, they are often rendered ineffective by the ability of microbial strains to develop genetic resistance and to grow in biofilms. Since many antimicrobial agents poorly penetrate biofilms, biofilm-associated infections often require high concentrations of antimicrobial agents for effective treatment. Among the various strategies that may be used to inhibit microbial biofilms, one strategy that has generated significant interest involves the use of bioactive surfaces that are resistant to microbial colonization. In this respect, we used matrix assisted pulsed laser evaporation (MAPLE) involving a pulsed KrF* excimer laser source (λ = 248 nm, τ = 25 ns, ν = 10 Hz) to obtain thin composite biopolymeric films containing natural (flavonoid) or synthetic (antibiotic) compounds as bioactive substances. Chemical composition and film structures were investigated by Fourier transform infrared spectroscopy and X-ray diffraction. Films morphology was studied by scanning electron microscopy and transmission electron microscopy. The antimicrobial assay of the microbial biofilms formed on these films was assessed by the viable cell counts method. The flavonoid-containing thin films showed increased resistance to microbial colonization

  15. Laboratory simulations of Mars evaporite geochemistry

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    Moore, Jeffrey M.; Bullock, Mark A.; Newsom, Horton; Nelson, Melissa

    2010-06-01

    Evaporite-rich sedimentary deposits on Mars were formed under chemical conditions quite different from those on the Earth. Their unique chemistries record the chemical and aqueous conditions under which they were formed and possibly subsequent conditions to which they were subjected. We have produced evaporite salt mineral suites in the laboratory under two simulated Martian atmospheres: (1) present-day and (2) a model of an ancient Martian atmosphere rich in volcanic gases. The composition of these synthetic Mars evaporites depends on the atmospheres under which they were desiccated as well as the chemistries of their precursor brines. In this report, we describe a Mars analog evaporite laboratory apparatus and the experimental methods we used to produce and analyze the evaporite mineral suites. The acidic, “paleo-Mars” gas mixture was CO2 with trace amounts of SO2, N2O, and HCl to simulate an atmosphere influenced by volcanic emissions. Brines formed by the interaction of water with an SNC-derived synthetic Mars mineral mix were produced under the acidic Mars atmospheric gas mixture. The brines were then desiccated under the two different simulated Mars conditions in the evaporite apparatus. Infrared reflectance spectroscopy and SEM microprobe analyses reveal that salts precipitated from the brine evaporated under simulated present Mars conditions were chemically different from those formed under the acidic Mars atmosphere conditions. The primary salt precipitated from the brine evaporated under present-day Mars conditions was a hydrated calcium sulfate, with lesser amounts of a magnesium sulfate and aluminum sulfate. Salts precipitated from the brine evaporated under an acidic atmosphere were dominated by magnesium sulfates, with lesser amounts of Na2SO4. These experiments suggest ways that relative cation abundances in Martian sulfate-bearing sediments can indicate the atmospheric and aqueous conditions under which they were formed. We conclude that the

  16. Design of microbial polysaccharide films for food packaging

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    Ferreira, Ana Rita Vasques

    2016-01-01

    The overuse of synthetic non-biodegradable plastic packaging in the last decades turned into a serious global environmental problem, once recycling and energy recovery are not perfect solutions. To overcome this problem, efforts have been done by researchers around the world to use biodegradable biopolymers from renewable resources as food packaging materials. In this thesis, FucoPol, a microbial exopolysaccharide has been studied as a sustainable alternative and the following questions we...

  17. Up-dating the Cholodny method using PET films to sample microbial communities in soil

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    Kordium V. A.

    2011-04-01

    Full Text Available The aim of this work was to investigate the use of PET (polyethylene terephtalate films as a modern development of Cholodny’s glass slides, to enable microscopy and molecular-based analysis of soil communities where spatial detail at the scale of microbial habitats is essential to understand microbial associations and interactions in this complex environment. Methods. Classical microbiological methods; attachment assay; surface tension measurements; molecular techniques: DNA extraction, PCR; confocal laser scanning microscopy (CLSM; micro-focus X-ray computed tomography (µCT. Results. We first show, using the model soil and rhizosphere bacteria Pseudomonas fluorescens SBW25 and P. putida KT2440, that bacteria are able to attach and detach from PET films, and that pre-conditioning with a filtered soil suspension improved the levels of attachment. Bacteria attached to the films were viable and could develop substantial biofilms. PET films buried in soil were rapidly colonised by microorganisms which could be investigated by CLSM and recovered onto agar plates. Secondly, we demonstrate that µCT can be used to non-destructively visualise soil aggregate contact points and pore spaces across the surface of PET films buried in soil. Conclusions. PET films are a successful development of Cholodny’s glass slides and can be used to sample soil communities in which bacterial adherence, growth, biofilm and community development can be investigated. The use of these films with µCT imaging in soil will enable a better understanding of soil micro-habitats and the spatially-explicit nature of microbial interactions in this complex environment.

  18. Evaporite karst in Italy: a review

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    Jo De Waele

    2017-07-01

    Full Text Available Although outcropping rarely in Italy, evaporite (gypsum and anhydrite karst has been described in detail since the early 20th century. Gypsum caves are now known from almost all Italian regions, but are mainly localised along the northern border of the Apennine chain (Emilia Romagna and Marche, Calabria, and Sicily, where the major outcrops occur. Recently, important caves have also been discovered in the underground gypsum mines in Piedmont. During the late 80s and 90s several multidisciplinary studies were carried out in many gypsum areas, resulting in a comprehensive overview, promoting further research in these special karst regions. More recent and detailed studies focused on the gypsum areas of Emilia-Romagna and Sicily. Sinkholes related to Permian-Triassic gypsum have been studied in Friuli Venezia Giulia. This article reviews the state of the art regarding different aspects of evaporite karst in Italy focusing on the main new results.

  19. Origin and chemical composition of evaporite deposits

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    Moore, George William

    1960-01-01

    A comparative study of marine evaporite deposits forming at the present time along the pacific coast of central Mexico and evaporite formations of Permian age in West Texas Basin was made in order to determine if the modern sediments provide a basis for understanding environmental conditions that existed during deposition of the older deposits. The field work was supplemented by investigations of artificial evaporite minerals precipitated in the laboratory and by study of the chemical composition of halite rock of different geologic ages. The environment of deposition of contemporaneous marine salt deposits in Mexico is acidic, is strongly reducing a few centimeters below the surface, and teems with microscopic life. Deposition of salt, unlike that of many other sediments, is not wholly a constructional phenomenon. Permanent deposits result only if a favorable balance exists between deposition in the dry season and dissolution in the wet season. Evaporite formations chosen for special study in the West Texas Basin are, in ascending order, the Castile, Salado, and Rustler formations, which have a combined thickness of 1200 meters. The Castile formation is largely composed of gypsum rock, the Salado, halite rock, and the Rustler, quartz and carbonate sandstone. The lower part of the Castile formation is bituminous and contains limestone laminae. The Castile and Rustler formations thicken to the south at the expense of salt of the intervening Salado formation. The clastic rocks of the Rustler formation are interpreted as the deposits of a series of barrier islands north of which halite rock of the Salado was deposited. The salt is believed to have formed in shallow water of uniform density that was mixed by the wind. Where water depth exceeded the depth of the wind mixing, density stratification developed, and gypsum was deposited. Dense water of high salinity below the density discontinuity was overlain by less dense, more normally saline water which was derived from

  20. Multiple techniques for mineral identification of terrestrial evaporites relevant to Mars exploration

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    Stivaletta, N.; Dellisanti, F.; D'Elia, M.; Fonti, S.; Mancarella, F.

    2013-05-01

    Sulfates, commonly found in evaporite deposits, were observed on Mars surface during orbital remote sensing and surface exploration. In terrestrial environments, evaporite precipitation creates excellent microniches for microbial colonization, especially in desert areas. Deposits comprised of gypsum, calcite, quartz and silicate deposits (phyllosilicates, feldspars) from Sahara Desert in southern Tunisia contain endolithic colonies just below the rock surface. Previous optical observations verified the presence of microbial communities and, as described in this paper, spectral visible analyses have led to identification of chlorophylls belonging to photosynthetic bacteria. Spectral analyses in the infrared region have clearly detected the presence of gypsum and phyllosilicates (mainly illite and/or smectite), as well as traces of calcite, but not quartz. X-ray diffraction (XRD) analysis has identified the dominant presence of gypsum as well as that of other secondary minerals such as quartz, feldspars and Mg-Al-rich phyllosilicates, such as chlorite, illite and smectite. The occurrence of a small quantity of calcite in all the samples was also highlighted by the loss of CO2 by thermal analysis (TG-DTA). A normative calculation using XRD, thermal data and X-ray fluorescence (XRF) analysis has permitted to obtain the mineralogical concentration of the minerals occurring in the samples. The combination of multiple techniques provides information about the mineralogy of rocks and hence indication of environments suitable for supporting microbial life on Mars surface.

  1. Effect of different film packaging on microbial growth in minimally processed cactus pear (Opuntia ficus-indica).

    Science.gov (United States)

    Palma, A; Mangia, N P; Fadda, A; Barberis, A; Schirra, M; D'Aquino, S

    2013-01-01

    Microorganisms are natural contaminants of fresh produce and minimally processed products, and contamination arises from a number of sources, including the environment, postharvest handling and processing. Fresh-cut products are particularly susceptible to microbial contaminations because of the changes occurring in the tissues during processing. In package gas composition of modified atmosphere packaging (MAP) in combination with low storage temperatures besides reducing physiological activity of packaged produce, can also delay pathogen growth. Present study investigated on the effect of MAPs, achieved with different plastic films, on microbial growth of minimally processed cactus pear (Opuntio ficus-indica) fruit. Five different plastic materials were used for packaging the manually peeled fruit. That is: a) polypropylene film (Termoplast MY 40 micron thickness, O2 transmission rate 300 cc/m2/24h); b) polyethylene film (Bolphane BHE, 11 micron thickness, O2 transmission rate 19000 cc/m2/24h); c) polypropylene laser-perforated films (Mach Packaging) with 8, 16 or 32 100-micron holes. Total aerobic psychrophilic, mesophilic microorganisms, Enterobacteriaceae, yeast, mould populations and in-package CO2, O2 and C2H4 were determined at each storage time. Different final gas compositions, ranging from 7.8 KPa to 17.1 KPa O2, and 12.7 KPa to 2.6 KPa CO2, were achieved with MY and micro perforated films, respectively. Differences were detected in the mesophilic, Enterobacteriaceae and yeast loads, while no difference was detected in psychrophilic microorganisms. At the end of storage, microbial load in fruits sealed with MY film was significantly lower than in those sealed with BHE and micro perforated films. Furthermore, fruits packed with micro-perforated films showed the highest microbial load. This occurrence may in part be related to in-package gas composition and in part to a continuous contamination of microorganisms through micro-holes.

  2. Point locations and characteristics of evaporite-related potash deposits

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This spatial database of evaporite-related potash deposits and occurrences provides location and descriptive information for 981 deposits and occurrences that are...

  3. A global survey of Precambrian evaporites: Implications for Proterozoic paleoenvironments

    Science.gov (United States)

    Evans, D. A.

    2006-05-01

    Evaporites are sedimentary rocks comprising minerals that crystallized from supersaturation of surface waters due to solar-driven desiccation. They, or their metamorphic relics and pseudomorphs, are abundant in the geologic record and document changes in paleoclimate, sealevel, and marine chemistry. Phanerozoic evaporites have been well described and summarized, in no small part due to their role as hydrocarbon seals, as well as sources of salinity in hydrothermal fluids that concentrate metal deposits. Precambrian evaporites are abundant in discrete number of instances but are generally less voluminous; their long-term preservation is limited by subsurface mineral dissolution as well as tectonic crustal recycling. Unlike Precambrian glacial deposits, which have been globally catalogued several times during the past fifty years, Precambrian evaporites have been compiled only partially in a few rare studies. A new, global survey of Precambrian evaporites (mainly pseudomorphs after gypsum, anhydrite, and halite) documents over 100 examples, including ten of Archean age. About 20 deposits have total preserved or estimated salt volumes exceeding 1000 cubic km, and these are restricted to the Proterozoic Era. One of the most impressive episodes of evaporite deposition in the entire geologic record occurred at about 800 Ma, coincident with the onset of Rodinia supercontinental fragmentation. These evaporites are preserved primarily as calcium-sulfates, totalling about 350,000 cubic km in volume. The next major global peak in evaporite deposition occurred in late Ediacaran to Early Cambrian time, totalling more than 1.5 million cubic km of mixed sulfates and halites. These peaks rival the great salt records of the Late Devonian, Late Permian, and Late Jurassic, and the molar volumes of deposited salt are comparable to the current inventory of oceanic salinity. Questions for future consideration include: what does the removal of this much salinity from the oceans, in these

  4. Evaporite-karst problems and studies in the USA

    Science.gov (United States)

    Johnson, K.S.

    2008-01-01

    Evaporites, including rock salt (halite) and gypsum (or anhydrite), are the most soluble among common rocks; they dissolve readily to form the same types of karst features that commonly are found in limestones and dolomites. Evaporites are present in 32 of the 48 contiguous states in USA, and they underlie about 40% of the land area. Typical evaporite-karst features observed in outcrops include sinkholes, caves, disappearing streams, and springs, whereas other evidence of active evaporite karst includes surface-collapse structures and saline springs or saline plumes that result from salt dissolution. Many evaporites also contain evidence of paleokarst, such as dissolution breccias, breccia pipes, slumped beds, and collapse structures. All these natural karst phenomena can be sources of engineering or environmental problems. Dangerous sinkholes and caves can form rapidly in evaporite rocks, or pre-existing karst features can be reactivated and open up (collapse) under certain hydrologic conditions or when the land is put to new uses. Many karst features also propagate upward through overlying surficial deposits. Human activities also have caused development of evaporite karst, primarily in salt deposits. Boreholes (petroleum tests or solution-mining operations) or underground mines may enable unsaturated water to flow through or against salt deposits, either intentionally or accidentally, thus allowing development of small to large dissolution cavities. If the dissolution cavity is large enough and shallow enough, successive roof failures can cause land subsidence and/or catastrophic collapse. Evaporite karst, natural and human-induced, is far more prevalent than is commonly believed. ?? 2007 Springer-Verlag.

  5. Microbial dynamics during aerobic exposure of corn silage stored under oxygen barrier or polyethylene films.

    Science.gov (United States)

    Dolci, Paola; Tabacco, Ernesto; Cocolin, Luca; Borreani, Giorgio

    2011-11-01

    The aims of this study were to compare the effects of sealing forage corn with a new oxygen barrier film with those obtained by using a conventional polyethylene film. This comparison was made during both ensilage and subsequent exposure of silage to air and included chemical, microbiological, and molecular (DNA and RNA) assessments. The forage was inoculated with a mixture of Lactobacillus buchneri, Lactobacillus plantarum, and Enterococcus faecium and ensiled in polyethylene (PE) and oxygen barrier (OB) plastic bags. The oxygen permeability of the PE and OB films was 1,480 and 70 cm³ m⁻² per 24 h at 23°C, respectively. The silages were sampled after 110 days of ensilage and after 2, 5, 7, 9, and 14 days of air exposure and analyzed for fermentation characteristics, conventional microbial enumeration, and bacterial and fungal community fingerprinting via PCR-denaturing gradient gel electrophoresis (DGGE) and reverse transcription (RT)-PCR-DGGE. The yeast counts in the PE and OB silages were 3.12 and 1.17 log₁₀ CFU g⁻¹, respectively, with corresponding aerobic stabilities of 65 and 152 h. Acetobacter pasteurianus was present at both the DNA and RNA levels in the PE silage samples after 2 days of air exposure, whereas it was found only after 7 days in the OB silages. RT-PCR-DGGE revealed the activity of Aspergillus fumigatus in the PE samples from the day 7 of air exposure, whereas it appeared only after 14 days in the OB silages. It has been shown that the use of an oxygen barrier film can ensure a longer shelf life of silage after aerobic exposure.

  6. Evaporites as a source for oil

    Energy Technology Data Exchange (ETDEWEB)

    Schreiber, B.C.; Benalihioulhaj, S. (Queens Coll., Flushing, NY (United States). Dept. of Geology); Philp, R.P. (Oklahoma Univ., Norman, OK (United States). School of Geology and Geophysics)

    1993-02-01

    Organic matter, present in some sediments, acts as the source for hydrocarbons and has been studied at great length, but organic-rich sediments from hypersaline environments are just beginning to be understood. Many types of organic matter from such restricted environments have been identified, and in this study their maturation pathways and products are being explored. By collecting biologically-identified organic matter produced within modern evaporative environments from a number of different marine and nonmarine settings and carrying out detailed geochemical examination of samples we are gradually beginning to understand these materials. The organic samples collected were from evaporative marine, sabkha, and lacustrine deposits, and have been subjected to two types of artificial maturation, hydrous and confined pyrolysis, over a fairly wide range of temperatures (1500 to 350[degrees]C). The biomarker products of these treatments are being analyzed and followed in great detail. Analyses of saturate and aromatic hydrocarbons as well as sulfur compounds in the original and the matured samples provide a comprehensive view of the biomarker assemblages associated with these different depositional environments at different stages of maturity. Infrared spectroscopy and Rock Eval pyrolysis of both the isolated kerogens from both the original and pyrolyzed samples has permitted us to clearly characterize the functional groupings on the one hand and the free hydrocarbons, the potential hydrocarbons, and the oxygenated compounds on the other hand. We have thus been able to demonstrate the potential of the organic matter associated with the different evaporitic environments to act as a good source for oil generation.

  7. Hydro-gelified and film forming formulation of microbial plant biostimulants for crop residues treatment on conservation agriculture systems

    Directory of Open Access Journals (Sweden)

    Oancea F.

    2016-05-01

    Full Text Available Microbial plant biostimulants represent one of the solutions for the negative impacts associated with high residues agricultural systems. We developed a hydro-gelified and film forming formulation, which we used for in situ formation of a bio-composite mulch, by treatment on crop residues. Into this hydro-gelified and film forming composition we included microbial biostimulants strains, Trichoderma asperellum T36 and Brevibacillus parabrevis B50. We tested the effects of application of such microbial plant biostimulant formulation on polyamines and ortosilicic acid release from a mixture of hairy vetch and corn residues, on controlled conditions. We evaluated the influence of crop residues treatment with our formulation on crop yield and soil characteristics - water stable aggregates, glomalin related soil proteins. The results demonstrate that treatments on crop residues with our formulation of microbial plant biostimulants compensates some disadvantages of high residues conservation agriculture, enhancing its effects on soil aggregate stability, due to the promotion of glomalin related soil proteins formation.

  8. Bacterial and Archaeal Lipids Recovered from Subsurface Evaporites of Dalangtan Playa on the Tibetan Plateau and Their Astrobiological Implications

    Science.gov (United States)

    Cheng, Ziye; Xiao, Long; Wang, Hongmei; Yang, Huan; Li, Jingjing; Huang, Ting; Xu, Yi; Ma, Nina

    2017-11-01

    Qaidam Basin (Tibetan Plateau) is considered an applicable analogue to Mars with regard to sustained extreme aridity and abundant evaporites. To investigate the possibility of the preservation of microbial lipids under these Mars analog conditions, we conducted a mineralogical and organic geochemistry study on samples collected from two Quaternary sections in Dalangtan Playa, northwestern Qaidam Basin, which will enhance our understanding of the potential preservation of molecular biomarkers on Mars. Two sedimentary units were identified along two profiles: one salt unit characterized by a predominance of gypsum and halite, and one detrital unit with a decrease of gypsum and halite and enrichment in siliciclastic minerals. Bacterial fatty acids and archaeal acyclic diether and tetraether membrane lipids were detected, and they varied throughout the sections in concentration and abundance. Bacterial and archaeal biomolecules indicate a dominance of Gram-positive bacteria and halophilic archaea in this hypersaline ecosystem that is similar to those in other hypersaline environments. Furthermore, the abundance of bacterial lipids decreases with the increase of salinity, whereas archaeal lipids showed a reverse trend. The detection of microbial lipids in hypersaline environments would indicate, for example on Mars, a high potential for the detection of microbial biomarkers in evaporites over geological timescales.

  9. Physical vapor deposited titanium thin films for biomedical applications: Reproducibility of nanoscale surface roughness and microbial adhesion properties

    Science.gov (United States)

    Lüdecke, Claudia; Bossert, Jörg; Roth, Martin; Jandt, Klaus D.

    2013-09-01

    The surface topography is of great importance for the biological performance of titanium based implants since it may influence the initial adsorption of proteins, cell response, as well as microbial adhesion. A recently described technique for the preparation of titanium thin films with an adjustable surface roughness on the nanometer scale is the physical vapor deposition (PVD). The aims of this study were to statistically evaluate the reproducibility of nanorough titanium thin films prepared by PVD using an atomic force microscopy (AFM) based approach, to test the microbial adhesion in dependence of the nanoscale surface roughness and to critically discuss the parameters used for the characterization of the titanium surfaces with respect to AFM microscope settings. No statistically significant differences were found between the surface nanoroughnesses of the PVD prepared titanium thin films. With increasing surface nanoroughness, the coverage by Escherichia coli decreased and the microbial cells were increasingly patchy distributed. The calculated roughness values significantly increased with increasing AFM scan size, while image resolution and pixel density had no influence on this effect. Our study shows that PVD is a suitable tool to reproducibly prepare titanium thin films with a well-defined surface topography on the nanometer scale. These surfaces are, thus, a suitable 2D model system for studies addressing the interaction between surface nanoroughness and the biological system. First results show that surface roughness even on the very low nanometer scale has an influence on bacterial adhesion behavior. These findings give new momentum to biomaterials research and will support the development of biomaterials surfaces with anti-infectious surface properties.

  10. Slanic Tuff and associated Miocene evaporite deposits, Eastern Carpathians, Romania

    Science.gov (United States)

    Bojar, Ana-Voica; Halas, Stanislaw; Barbu, Victor; Bojar, Hans-Peter; Wojtowicz, Artur; Duliu, Octavian

    2017-04-01

    Miocene tuffs of calcalkaline composition are widespread in the Carpathians, Pannonian and Eastern Alpine realm. Their occurrences are described in outcrops as well as in the subsurface. The presence of such tuffs may offer important criteria for stratigraphic correlations and help to establish the absolute age of deposits and associated climatic and environmental changes. The Green Stone Hill (Muntele Piatra Verde) is situated to the north of Slanic-Prahova salt mine, in the bend region of the Eastern Carpathians, Romania. From bottom to top the section is composed of: marls with Globigerina followed by the so called Slanic tuff, gypsum and salt breccia and, on the top, radiolarian bearing shales. The stratigraphic age of the section is Middle to Upper Badenian (nannoplankton zones NN5 to NN6). XRD investigations of the green Slanic tuff show that the main mineralogical component is clinoptilolite (zeolite) followed by quartz and plagioclase. For this type of tuff there is no crystalline phase, which may be used for radiometric dating. In the middle part of the green tuff interval, we found discrete layers of a much coarser white tuff, with mineralogy consisting of quartz, plagioclase, biotite and clinoptilolite. The white tuff forming distinct layers within the green tuff, has an andesitic composition. 40Ar/39Ar dating of biotite concentrates from the white tuff gives an age of 13.6±0.2Ma, the dated layer being situated below the gypsum and salt breccia. We consider that the age is well constraining the time when the green tuffs were formed at the border of the basin. From this level upwards discrete gypsum layers occurs within the green tuffs, the age may be considered as indicating the base of the evaporitic sequence. To the south-east, from this level upwards evaporites, mainly salt formed. The age suggests that evaporitic deposits formed after the Mid Badenian climatic optimum, evaporitic formation being related to restricted circulation due the drop of sea

  11. On the effects of subsurface parameters on evaporite dissolution (Switzerland).

    Science.gov (United States)

    Zidane, Ali; Zechner, Eric; Huggenberger, Peter; Younes, Anis

    2014-05-01

    Uncontrolled subsurface evaporite dissolution could lead to hazards such as land subsidence. Observed subsidences in a study area of Northwestern Switzerland were mainly due to subsurface dissolution (subrosion) of evaporites such as halite and gypsum. A set of 2D density driven flow simulations were evaluated along 1000 m long and 150 m deep 2D cross sections within the study area that is characterized by tectonic horst and graben structures. The simulations were conducted to study the effect of the different subsurface parameters that could affect the dissolution process. The heterogeneity of normal faults and its impact on the dissolution of evaporites is studied by considering several permeable faults that include non-permeable areas. The mixed finite element method (MFE) is used to solve the flow equation, coupled with the multipoint flux approximation (MPFA) and the discontinuous Galerkin method (DG) to solve the diffusion and the advection parts of the transport equation. Results show that the number of faults above the lower aquifer that contains the salt layer is considered as the most important factor that affects the dissolution compared to the other investigated parameters of thickness of the zone above the halite formation, a dynamic conductivity of the lower aquifer, and varying boundary conditions in the upper aquifer. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Characterization of plasma-polymerized 4-vinyl pyridine with silver nanoparticies on poly(ethylene terephthalate) film for anti-microbial properties

    DEFF Research Database (Denmark)

    Jiang, J.; Winther-Jensen, Bjørn; Kjær, Erik Michael

    2006-01-01

    on the poly(4-vinyl pyridine) coating by UV irradiation in Silver nitride water solution, in order to enhance the anti-microbial properties. Different kinds of modified PET films were tested for anti-microbial properties against yeast (Debaryomyces hansenii) by using microbiological analyser mu-4200......4-vinyl pyridine was polymerized on poly(ethylene terephthalate) (PET) film by using lower energy pulsed AC plasma under low pressure in Ar atmosphere. The plasma polymerized coating was characterized by ATR Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), field emission...

  13. Identification, prediction and mitigation of sinkhole hazards in evaporite karst areas

    OpenAIRE

    F. Gutiérrez; Cooper, Anthony; Johnson, Kenneth

    2008-01-01

    Abstract Sinkholes usually have a higher probability of occurrence and a greater genetic diversity in evaporite terrains than in carbonate karst areas. This is because evaporites have a higher solubility, and commonly a lower mechanical strength. Subsidence damage resulting from evaporite dissolution generates substantial losses throughout the world, but the causes are only well-understood in a few areas. To deal with these hazards, a phased approach is needed for sinkhole identification, inv...

  14. Photoactivated chlorophyllin-based gelatin films and coatings to prevent microbial contamination of food products.

    Science.gov (United States)

    López-Carballo, G; Hernández-Muñoz, P; Gavara, R; Ocio, M J

    2008-08-15

    The aim of this work was to develop antimicrobial photosensitizer-containing edible films and coatings based on gelatin as the polymer matrix, incorporating sodium magnesium chlorophyllin (E-140) and sodium copper chlorophyllin (E-141). Chlorophyllins were incorporated into the gelatin film-forming solution and the inhibiting effect of the cast films was tested against Staphylococcus aureus and Listeria monocytogenes. The results demonstrated that water soluble sodium magnesium chlorophyllin and water soluble sodium copper chlorophyllin reduced the growth of S. aureus and L. monocytogenes by 5 log and 4 log respectively. Subsequently, the activity of self-standing films and coatings containing E-140 was assessed on cooked frankfurters inoculated with S. aureus and L. monocytogenes. These tests showed that it was possible to reduce microorganism growth in cooked frankfurters inoculated with S. aureus and L. monocytogenes by covering them with sodium magnesium chlorophyllin-gelatin films and coatings.

  15. Microbial status, aerobic stability and fermentation of maize silage sealed with an oxygen barrier film or standard polyethylene film

    Directory of Open Access Journals (Sweden)

    Szilvia Orosz

    2013-03-01

    Full Text Available An experiment was conducted to compare a bunker silo sealing system comprising an oxygen barrier film (OB: 45μm thickness with protective woven polypropylene with one comprising standard black polyethylene film (S; 125μm thickness with protective tyres. Analysis of samples taken to 30 cm depth after 365 days of storage showed no differences in pH or lactic acid between the two sealing systems. There were no differences in aerobic bacterial count between silages. Whilst 2.56 log10 CFU moulds g-1 fresh weight were found in samples of silage sealed with S, no moulds were found in samples of silage sealed with OB. Aerobic stability, averaged 249 hours and 184 hours for OB and S, respectively. The OB system probably inhibited the development of the micro-organisms responsible for the initiation of aerobic deterioration to a greater extent than the standard silo sealing system.  

  16. Evaporite deposits of Bogota area, Cordillera Oriental, Colombia

    Science.gov (United States)

    McLaughlin, Donald H.

    1972-01-01

    Four evaporite-bearing stratigraphic zones are known in Cretaceous strata of the Cordillera Oriental of Colombia north and east of Bogota. The easternmost and oldest zone is probably of Berriasian to Valanginian age. The next oldest is probably late Barremian to early Aptian in age. The third appears to be Aptian. The westernmost and best known sequence in the Sabana de Bogota is Turonian to early Coniacian in age. This youngest sequence contains the thickest salt deposits known in Colombia and is probably the most widespread geographically.Most of the rock salt exposed in the three accessible mines (at Zipaquira, Nemocon, and Upin) has a characteristic lamination of alternating slightly argillaceous and highly argillaceous salt layers of varied but moderate thickness. Black, calcareous claystone, commonly very pyritic, is interbedded conformably with the laminated salt in many places throughout the deposits. Fragments of black claystone derived from the thinner interbeds are ubiquitous in all deposits, both as concordant breccia zones and as isolated clasts.Anhydrite is scarce at Zipaquira and apparently even rarer at Nemocon and Upin. Gypsum is produced at three small deposits in the oldest evaporite zone where it probably was concentrated by leaching of salt initially associated with it.The two intervening evaporite zones are not exposed, but their existence and distribution are indicated by brine springs and locally by "rute," a distinctive black, calcareous mud formed by the leaching of salt beds.Fossils show that the youngest salt-claystone zone, in the Sabana de Bogota, is contemporary with associated hematitic sandstone and siltstone, and with carbonaceous and locally coaly claystone. Although evidence is poor, this same facies relation probably exists within the other three evaporite zones.All salt deposits in this study probably are associated with anticlines, a relation best exemplified by the deposits on the Sabana de Bogota. Within these anticlines the

  17. Anti-microbial polymer films for food packaging: Poster at the 3rd International Symposium on Food Packaging: Ensuring the Safety, Quality and Traceability of Foods, 17-19 November 2004, Barcelona, Spain

    OpenAIRE

    Sandmeier, D; Kensbock, E.

    2004-01-01

    Anti-microbial fitted polymers can protect the surface of food from unwanted microorganisms like bacteria, yeast and mould or prevent or suppress their growth. This type of active packaging contributes to a better quality and shelf life. Today the extended use of polymers offers new possibilities to construct anti-microbial packaging materials. There are two different mechanisms of anti-microbial fitted films, surface fixed anti-microbial groups or release of active agents. Based on the relea...

  18. Frictional properties and slip stability of active faults within carbonate-evaporite sequences: The role of dolomite and anhydrite

    NARCIS (Netherlands)

    Scuderi, M.M.; Niemeijer, A.R.; Collettini, C.; Marone, C.

    2013-01-01

    Seismological observations show that many destructive earthquakes nucleate within, or propagate through, thick sequences of carbonates and evaporites. For example, along the Apennines range (Italy) carbonate and evaporite sequences are present at hypocentral depths for recent major earthquakes

  19. SSeismic imaging of Messinian Evaporites in the Ionian Basin

    Science.gov (United States)

    Camerlenghi, Angelo; Del Ben, Anna; Forlin, Edy; Geletti, Riccardo; Mocnik, Arianna; Saule, Marco

    2017-04-01

    The understanding of the Messinian Salinity Crisis (MSC) as a Mediterranean basin-wide event requires an improved knowledge of the stratigraphy in the deep basins and continental margins. The seismic markers of the deposition of Messinian evaporites in the deep Mediterranean basins identify two end-members in the Western Mediterranean basins and in the Levant Basin. In the Western Mediterranean a consistent succession of three seismo-stratigraphic units in the deep basins, the so called seismic trilogy, can be correlated across thousands of kilometers in the Algero-Balearic and Provençal basins with a fairly constant distribution of the Lower Unit, the Mobile Unit, and the overlying Upper Unit. In the Levant Basin, one single seismostratigraphic unit defines the MSC, composed of up to 6 alternations of a transparent and layered seismic units. The causes of the these different seismic expressions of the MSC are presently under investigation. Here we report on the seismic signal analysis performed on vintage multichannel seismic reflection profiles from the Ionian Basin, that is located immediately down-flow from the sill separating the Western Mediterranean Basins and the Levant Basin during the postulated re-flooding of the Mediterranean at the end of the MSC. Given the intense post-Messinian tectonic deformation induced plate convergence below the Calabrian and Hellenic margins, the challenge in this area is the identification of an undisturbed deep sea evaporitic sequence where the data quality allows a reliable reconstruction of the seismic units. With the aid of a extensive velocity analysis and pre-stack migration in time and depth domains, we have been able to define a third type of deep basin Messinian seismic sequence characterizing the Ionian Basin. This is composed by a very thin (one or two high amplitude reflectors) and discontinuous Lower Unit, that makes up basal lens-shaped bodies overlain by a nearly 1 km-thick Mobile Unit, typically composed of a

  20. Uranium-Bearing Evaporite Mineralization Influencing Plume Persistence. Literature Review and DOE-LM Site Surveys

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2016-05-01

    This report on evaporite mineralization was completed as an Ancillary Work Plan for the Applied Studies and Technology program under the U.S. Department of Energy (DOE) Office of Legacy Management (LM). This study reviews all LM sites under Title I and Title II of the Uranium Mill Tailings Radiation Control Act (UMTRCA) and one Decontamination and Decommissioning site to provide (1) a summary of which sites have evaporite deposits, (2) any available quantitative geochemical and mineralogical analyses, and (3) references to relevant reports. In this study, “evaporite” refers to any secondary mineral precipitate that occurs due to a loss of water through evaporative processes. This includes efflorescent salt crusts, where this term refers to a migration of dissolved constituents to the surface with a resulting salt crust, where “salt” can refer to any secondary precipitate, regardless of constituents. The potential for the formation of evaporites at LM sites has been identified, and may have relevance to plume persistence issues. Evaporite deposits have the potential to concentrate and store contaminants at LM sites that could later be re-released. These deposits can also provide a temporary storage mechanism for carbonate, chloride, and sulfate salts along with uranium and other contaminants of concern (COCs). Identification of sites with evaporites will be used in a new technical task plan (TTP), Persistent Secondary Contaminant Sources (PeSCS), for any proposed additional sampling and analyses. This additional study is currently under development and will focus on determining if the dissolution of evaporites has the potential to hinder natural flushing strategies and impact plume persistence. This report provides an initial literature review on evaporites followed by details for each site with identified evaporites. The final summary includes a table listing of all relevant LM sites regardless of evaporite identification.

  1. Evaporite karst of Albania: main features and cases of environmental degradation

    Science.gov (United States)

    Parise, Mario; Qiriazi, Perikli; Sala, Skender

    2008-01-01

    The present paper focuses on the description of the main evaporite karst areas of Albania, and on their environmental problems. Even though the majority of the karst areas in Albania is represented by carbonates, evaporites crop out significantly at several sites, and deserve a specific attention for their morphological, karstic and speleological peculiarities. Vulnerability of karst is well marked by pollution and degradation problems in regions such as Dumre (central Albania), where some tens of lakes of karst origin are present in the Permian-Triassic evaporites. Water pollution with negative effects on the local ecosystems, and anthropogenic changes of the natural karst landscape in the last century resulted in intense environmental degradation at Dumre. Messinian evaporites crop out in the Kavaja area (near the Adriatic coast), and at other sites in central-southern Albania. In these areas, surface karst morphology is characterized by a number of dolines, ponors and blind valleys, which often correspond to inlet points of subterranean drainages and caves. Notwithstanding these peculiarities, and the relevance of the area for biospeleological studies, many caves have been destroyed by quarrying activities, resulting in severe losses to the natural heritage. Following a general description of the evaporite karst areas of Albania, the paper focuses on the present situation of the evaporites in the country, which is frequently affected by degradation and environmental losses in the karst landscape, and pollution of the aquifers.

  2. Scalable production of microbially-mediated ZnS nanoparticles and application to functional thin films

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Ji Won [ORNL; Ivanov, Ilia N [ORNL; Joshi, Pooran C [ORNL; Armstrong, Beth L [ORNL; Wang, Wei [ORNL; Jung, Hyunsung [ORNL; Rondinone, Adam Justin [ORNL; Jellison Jr, Gerald Earle [ORNL; Meyer III, Harry M [ORNL; Jang, Gyoung Gug [Oak Ridge National Laboratory (ORNL); Meisner, Roberta [Oak Ridge National Laboratory (ORNL); Duty, Chad E [ORNL; Phelps, Tommy Joe [ORNL

    2014-01-01

    A series of semiconducting zinc sulfide (ZnS) nanoparticles were scalably, reproducibly, controllably, and economically synthesized with anaerobic metal-reducing Thermoanaerobacter species. They reduced partially oxidized sulfur sources to sulfides that extracellularly and thermodynamically incorporated with zinc ions to produce sparingly soluble ZnS nanoparticles with ~5 nm crystallites at yields of ~5 g l 1 month 1. A predominant sphalerite formation was facilitated by rapid precipitation kinetics, low cation/anion ratio, higher zinc concentration, water stabilization, or some combination of the four. The sphalerite ZnS nanoparticles exhibited narrow size distribution, high emission intensity, and few native defects. Scale-up and emission tunability using copper-doping were confirmed spectroscopically. Surface characterization was determined using Fourier transform infrared and X-ray photoelectron spectroscopies, which confirmed amine and carboxylic acid not only maintaining a nano-dimensional average crystallite size, but also increasing aggregation. Application of ZnS nanoparticle ink to a functional thin film was successfully tested for potential future applications.

  3. The persistence of a chlorophyll spectral biosignature from Martian evaporite and spring analogues under Mars-like conditions

    Science.gov (United States)

    Stromberg, J. M.; Applin, D. M.; Cloutis, E. A.; Rice, M.; Berard, G.; Mann, P.

    2014-07-01

    Spring and evaporite deposits are considered two of the most promising environments for past habitability on Mars and preservation of biosignatures. Manitoba, Canada hosts the East German Creek (EGC) hypersaline spring complex, and the post impact evaporite gypsum beds of the Lake St. Martin (LSM) impact. The EGC complex has microbial mats, sediments, algae and biofabrics, while endolithic communities are ubiquitous in the LSM gypsum beds. These communities are spectrally detectable based largely on the presence of a chlorophyll absorption band at 670 nm however, the robustness of this feature under Martian surface conditions was unclear. Biological and biology-bearing samples from EGC and LSM were exposed to conditions similar to the surface of present day Mars (high UV flux, 100 mbar, anoxic, CO2 rich) for up to 44 days, and preservation of the 670 nm chlorophyll feature and chlorophyll red-edge was observed. A decrease in band depth of the 670 nm band ranging from ~16 to 80% resulted, with correlations seen in the degree of preservation and the spatial proximity of samples to the spring mound and mineral shielding effects. The spectra were deconvolved to Mars Exploration Rover (MER) Pancam and Mars Science Laboratory (MSL) Mastcam science filter bandpasses to investigate the detectability of the 670 nm feature and to compare with common mineral features. The red-edge and 670 nm feature associated with chlorophyll can be distinguished from the spectra of minerals with features below ~1000 nm, such as hematite and jarosite. However, distinguishing goethite from samples with the chlorophyll feature is more problematic, and quantitative interpretation using band depth data makes little distinction between iron oxyhydroxides and the 670 nm chlorophyll feature. The chlorophyll spectral feature is observable in both Pancam and Mastcam, and we propose that of the proposed EXOMARS Pancam filters, the PHYLL filter is best suited for its detection.

  4. Calcareous nannofossil events in the pre-evaporitic Messinian

    Science.gov (United States)

    Negri, Alessandra; Lozar, Francesca

    2017-04-01

    During the Messinian (7.2 to 5.3 Ma) the Mediterranean area experienced fast and deep climatic and eustatic structural changes. The stratigraphic framework for this interval is relatively well constrained and the beginning of the Messinian salinity crisis dated at 5.97 Ma determine a duration of at least 1.2 Ma for the pre-evaporitic Messinian that is object of this study. Several sites (Faneromeni, Pissouri, Polemi Fanantello borehole, Lemme, Pollenzo, Govone, Moncalvo; Wade and Bown, 2006; Kouwenhoven et al 2006, Morigi et al 2007, Lozar et al 2010, Dela Pierre et al 2011) show similar calcareous nannofossil record behavior, with several Sphenolithus spp. peaks recognised at different quotes in each of the sections. Aim of the present work is to compare the calcareous nannofossil data achieved in the above mentioned sections: interestingly, the occurrence of strongly oligotypic assemblages related to high salinity and unstable environments, appear to correlate precisely among the investigated sites and occur immediately before the onset of the Messinian salinity crisis, then offering the possibility to use them as bioevents for regional correlation. References Dela Pierre, F., Bernardi, E., Cavagna, S., Clari, P., Gennari, R., Irace, A., Lozar, F., Lugli, S., Manzi, V., Natalicchio, M., Roveri, M., Violanti, D., 2011. The record of the Messinian salinity crisis in the Tertiary Piedmont Basin (NW Italy): The Alba section revisited. Palaeogeography, Palaeoclimatology, Palaeoecology 310, 238-255. Kouwenhoven, T.J., Morigi, C., Negri, A., Giunta, S., Krijgsman, W., Rouchy, J.M., 2006 Paleoenvironmental evolution of the eastern Mediterranean during the Messinian: Constraints from integrated microfossil data of the Pissouri Basin (Cyprus). Marine Micropaleontology 60, 17-44. Lozar, F., Violanti, D., Dela Pierre, F., Bernardi, E., Cavagna, S., Clari, P., Irace, A., Martinetto, E., Trenkwalder, S., 2010. Calcareous nannofossils and foraminifers herald the Messinian

  5. Geothermal evolution of the evaporite-bearing sequences of the Lesser Himalaya, India

    Science.gov (United States)

    Singh, S. P.; Singh, B. P.

    2010-01-01

    Neoproterozoic evaporites occurring in the western part of the Lesser Himalaya in India, coeval to Pakistan, Iran and Oman evaporites, were investigated in order to understand the degree of metamorphism in them and in associated carbonates. The evaporite-bearing succession occurs in association of phyllite, quartzite and carbonate near the Main boundary Thrust. In order to learn the details about the burial history of these evaporite rocks, the Kübler illite crystallinity index (KI) was measured from the illite peaks of the clay minerals separated from the evaporite rocks and it indicated that this section has reached a maximum temperature up to ~300°C. Microthermometric measurements on fluid inclusions present in the associated dolomite show range of homogenization temperatures (Th), from 220 to 280°C, well within the temperature range of anchizone metamorphism. Additionally, dolomite shows a highly negative δ18O signature (mean, -15.5‰PDB), which is more likely related to diagenetic overprint from deep burial conditions rather than original precipitation from 18O-depleted seawater. The evaporites (sulfates and chloride) probably were transformed many times after their precipitation, but they have retained only the features developed during last one or two phases of alteration and deformation as they are continuously susceptible to minor changes in temperatures and stresses. The final temperature range of 42-78°C in sulfates and chloride gives thermal approximation estimate that is not in concordance with the thermal history of the basin and are likely related to conversion of anhydrite into gypsum and recrystallization of halite during exhumation. Highly negative oxygen isotopic composition, homogenization temperatures and KI values equivalent to a high anchizone metamorphism suggest a burial depth of ~10 km for these terminal Neoproterozoic evaporite-bearing sequences of the Lesser Himalaya.

  6. Anti-microbial surfaces: An approach for deposition of ZnO nanoparticles on PVA-Gelatin composite film by screen printing technique.

    Science.gov (United States)

    Meshram, J V; Koli, V B; Phadatare, M R; Pawar, S H

    2017-04-01

    Initially micro-organisms get exposed to the surfaces, this demands development of anti-microbial surfaces to inhibit their proliferation. Therefore, herein, we attempt screen printing technique for development of PVA-GE/ZnO nanocomposite (PG/ZnO) films. The synthesis of PG/ZnO nanocomposite includes two steps as: (i) Coating of Zinc Oxide nanoparticles (ZnO NPs) by poly ethylene glycol in order to be compatible with organic counterparts. (ii) Deposition of coated nanoparticles on the PG film surface. The results suggest the enhancement in anti-microbial activity of PG/ZnO nanocomposite over pure ZnO NPs against both Gram positive Bacillus subtilis and Gram negative Escherichia coli from zone of inhibition. The uniformity in deposition is further confirmed by scanning electron microscopy (SEM) images. The phase identification of ZnO NPs and formation of PG/ZnO nanocomposite has been confirmed by X-ray diffraction (XRD) analysis and UV-vis spectroscopy (UV-vis). The Attenuated total reflection Spectroscopy (ATR) analysis indicates the ester bond between PVA and gelatin molecules. The thermal stability of nanocomposite is studied by thermogravimetric analysis (TGA) revealing increase in crystallinity due to ZnO NPs which could be utilized to inhibit the growth of micro-organisms. The tensile strength is found to be higher and percent elongation is double of PG/ZnO nanocomposite than PG composite film. Copyright © 2016. Published by Elsevier B.V.

  7. Mediterranean salt giants beyond the evaporite model: The Sicily perspective

    Science.gov (United States)

    Carmelo Manuella, Fabio; Scribano, Vittorio; Carbone, Serafina; Hovland, Martin; Johnsen, Hans-Konrad; Rueslåtten, Håkon

    2017-04-01

    Mediterranean salt giants, occurring both in sub-seafloor and in onshore settings (the "Gessoso Solfifera Group"), are traditionally explained by repeated cycles of desiccation and replenishment of the entire basin. However, such hypotheses are strongly biased by mass balance calculations and geodynamic considerations. In addition, any hypothesis without full desiccation, still based on the evaporite model, should consider that seawater brines start to precipitate halite when 2/3 of the seawater has evaporated, and hence the level of the basin cannot be the same as the adjacent ocean. On the other hand, hydrothermal venting of hot saline brines onto the seafloor can precipitate salt in a deep marine basin if a layer of heavy brine exists along the seafloor. This process, likely related to sub-surface boiling or supercritical out-salting (Hovland et al., 2006), is consistent with geological evidence in the Red Sea "Deeps" (Hovland et al., 2015). Although supercritical out-salting and phase separation can sufficiently explain the formation of several marine salt deposits, even in deep marine settings, the Mediterranean salt giant formations can also be explained by the serpentinization model (Scribano et al., 2016). Serpentinization of abyssal peridotites does not involve seawater salts, and large quantities of saline brines accumulate in pores and fractures of the sub-seafloor serpentinites. If these rocks undergo thermal dehydration, for example, due to igneous intrusions, brines and salt slurries can migrate upwards as hydrothermal plumes, eventually venting at the seafloor, giving rise to giant salt deposits over time. These hydrothermal processes can take place in a temporal sequence, as it occurred in the "Caltanissetta Basin" (Sicily). There, salt accumulation associated with serpentinization started during Triassic times (and even earlier), and venting of heavy brines onto the seafloor eventually occurred in the Messinian via the hydrothermal plume mechanism

  8. PANI-Ag-Cu Nanocomposite Thin Films Based Impedimetric Microbial Sensor for Detection of E. coli Bacteria

    OpenAIRE

    Huda Abdullah; Norshafadzila Mohammad Naim; Noor Azwen Noor Azmy; Aidil Abdul Hamid

    2014-01-01

    PANI-Ag-Cu nanocomposite thin films were prepared by sol-gel method and deposited on the glass substrate using spin coating technique. Polyaniline was synthesized by chemical oxidative polymerization of aniline monomer in the presence of nitric acid. The films were characterized using XRD, FTIR, and UV-Visible spectroscopy. The performance of the sensor was conducted using electrochemical impedance spectroscopy to obtain the change in impedance of the sensor film before and after incubation w...

  9. Hydraulic testing of Salado Formation evaporites at the Waste Isolation Pilot Plant site: Second interpretive report

    Energy Technology Data Exchange (ETDEWEB)

    Beauheim, R.L. [Sandia National Labs., Albuquerque, NM (United States); Roberts, R.M.; Dale, T.F.; Fort, M.D.; Stensrud, W.A. [INTERA, Inc., Austin, TX (United States)

    1993-12-01

    Pressure-pulse, constant-pressure flow, and pressure-buildup tests have been performed in bedded evaporites of the Salado Formation at the Waste Isolation Pilot Plant (WIPP) site to evaluate the hydraulic properties controlling brine flow through the Salado. Transmissivities have been interpreted from six sequences of tests conducted on five stratigraphic intervals within 15 m of the WIPP underground excavations.

  10. Sedimentary cycles in coal and evaporite basins and the reconstruction of Paleozoic climate

    NARCIS (Netherlands)

    van den Belt, F.J.G.

    2012-01-01

    This thesis deals with large-scale processes controlling the formation of sedimentary cycles in coal and evaporite basins and their relation to large-scale fluctuations of Palaeozoic climate. Coal-clastic cycles dominate Pennsylvanian sequences in palaeo-equatorial basins from Euramerica. They

  11. Discovery of the Badenian evaporites inside the Carpathian Arc: implications for global climate change and Paratethys salinity

    Directory of Open Access Journals (Sweden)

    Báldi Katalin

    2017-06-01

    Full Text Available Massive evaporites were discovered in the Soltvadkert Trough (Great Plain, Hungary correlating to the Badenian Salinity Crisis (13.8 Ma, Middle Miocene on the basis of nannoplankton and foraminifera biostratigraphy. This new occurrence from Hungary previously thought to be devoid of evaporites is part of a growing body of evidence of evaporitic basins inside the Carpathian Arc. We suggest the presence of evaporites perhaps in the entire Central Paratethys during the salinity crisis. Different scenarios are suggested for what subsequently happened to these evaporites to explain their presence or absence in the geological record. Where they are present, scenario A suggests that they were preserved in subsiding, deep basins overlain by younger sediments that protected the evaporites from reworking, like in the studied area. Where they are absent, scenario B suggests recycling. Scenario B explains how the supposedly brackish Sarmatian could have been hyper/normal saline locally by providing a source of the excess salt from the reworking and dissolving of BSC halite into seawater. These scenarios suggest a much larger amount of evaporites locked up in the Central Paratethys during the salinity crisis then previously thought, probably contributing to the step-like nature of cooling of the Mid Miocene Climate Transition, the coeval Mi3b.

  12. Film

    OpenAIRE

    Balint, Ruth; Dolgopolov, Greg

    2008-01-01

    From the beginning of the twentieth century, Sydney defined cosmopolitanism and modernity in the national imagination, and central to this image was the cinema: its technology, its architecture, its stars, its marketing and the stories it circulated to its audiences about Australia and the world. Though it is difficult to define a genre of Sydney film, Sydney provided the backdrop for a host of ideas about the city, and later suburbia. Sydney came to be seen as a ‘tinsel town’ of cultural ban...

  13. Polyethylene Films Containing Silver Nanoparticles for Applications in Food Packaging: Characterization of Physico-Chemical and Anti-Microbial Properties.

    Science.gov (United States)

    Becaro, Aline A; Puti, Fernanda C; Correa, Daniel S; Paris, Elaine C; Marconcini, José M; Ferreira, Marcos D

    2015-03-01

    This paper reports the antibacterial effect and physico-chemical characterization of films containing silver nanoparticles for use as food packaging. Two masterbatches (named PEN and PEC) con- taining silver nanoparticles embedded in distinct carriers (silica and titanium dioxide) were mixed with low-density polyethylene (LDPE) in different compositions and extruded to produce plain films. These films were characterized by Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR). The morphology of the films showed the formation of agglomerates of nanoparticles in both PEN and PEC composites. X-ray analyses confirmed the presence of SiO2 in PEN samples and TiO2 in PEC samples. Thermal analyses indicated an increase in thermal stability of the PEC compositions. The antimicrobial efficacy was determined by applying the test strain for Escherichia coli and Staphylococcus aureus, according to the Japanese Industrial Standard Method (JIS Z 2801:2000). The films analyzed showed antimicrobial properties against the tested microorganisms, presenting better activity against the S. aureus than E. Coli. These findings suggest that LDPE films with silver nanoparticles are promising to provide a significant contribution to the quality and safety of packaged food.

  14. Railway deformation detected by DInSAR over active sinkholes in the Ebro Valley evaporite karst, Spain

    National Research Council Canada - National Science Library

    J P Galve; C Castañeda; F Gutiérrez

    2015-01-01

    ...) using Differential Synthetic Aperture Radar Interferometry (DInSAR) techniques. This area is affected by evaporite karst and the analysed railway corridors traverse active sinkholes that produce deformations in these infrastructures...

  15. Proterozoic low orbital obliquity and axial-dipolar geomagnetic field from evaporite palaeolatitudes.

    Science.gov (United States)

    Evans, David A D

    2006-11-02

    Palaeomagnetism of climatically sensitive sedimentary rock types, such as glacial deposits and evaporites, can test the uniformitarianism of ancient geomagnetic fields and palaeoclimate zones. Proterozoic glacial deposits laid down in near-equatorial palaeomagnetic latitudes can be explained by 'snowball Earth' episodes, high orbital obliquity or markedly non-uniformitarian geomagnetic fields. Here I present a global palaeomagnetic compilation of the Earth's entire basin-scale evaporite record. Magnetic inclinations are consistent with low orbital obliquity and a geocentric-axial-dipole magnetic field for most of the past two billion years, and the snowball Earth hypothesis accordingly remains the most viable model for low-latitude Proterozoic ice ages. Efforts to reconstruct Proterozoic supercontinents are strengthened by this demonstration of a consistently axial and dipolar geomagnetic reference frame, which itself implies stability of geodynamo processes on billion-year timescales.

  16. Earth analogs for Martian life - Microbes in evaporites, a new model system for life on Mars

    Science.gov (United States)

    Rothschild, Lynn J.

    1990-01-01

    It is suggested that 'oases' in which life forms may persist on Mars could occur, by analogy with terrestrial cases, in (1) rocks, as known in endolithic microorganisms, (2) polar ice caps, as seen in snow and ice algae, and (3) volcanic regions, as witnessed in the chemoautotrophs which live in ocean-floor hydrothermal vents. Microorganisms, moreover, have been known to survive in salt crystals, and it has even been shown that organisms can metabolize while encrusted in evaporites. Evaporites which may occur on Mars would be able to attenuate UV light, while remaining more transparent to the 400-700 nm radiation useful in photosynthesis. Suggestions are made for the selection of Martian exobiological investigation sites.

  17. Geochemical study of evaporite and clay mineral-oxyhydroxide samples from the Waste Isolation Pilot Plant site

    Energy Technology Data Exchange (ETDEWEB)

    Brookins, D.G. [Univ. of New Mexico, Albuquerque, NM (US). Dept. of Geology

    1993-06-01

    Samples of clay minerals, insoluble oxyhydroxides, and their host evaporites from the WIPP site have been studied for their major and minor elements abundances, x-ray diffraction characteristics, K-Ar ages, and Rb-Sr ages. This study was undertaken to determine their overall geochemical characteristics and to investigate possible interactions between evaporates and insoluble constituents. The evaporite host material is water-soluble, having Cl/Br ratios typical of marine evaporites, although the Br content is low. Insoluble material (usually a mixture of clay minerals and oxyhydroxide phases) yields very high Cl/Br ratios, possibly because of Cl from admixed halide minerals. This same material yields K/Rb and Th/U ratios in the normal range for shales; suggesting little, if any, effect of evaporite-induced remobilization of U, K, or Rb in the insoluble material. The rare-earth element (REE) data also show normal REE/chondrite (REE/CHON) distribution patterns, supporting the K/Rb and Th/U data. Clay minerals yield K-Ar dates in the range 365 to 390 Ma and a Rb-Sr isochron age of 428 {+-} 7 Ma. These ages are well in excess of the 220- to 230-Ma formational age of the evaporites, and confirm the detrital origin of the clays. The ages also show that any evaporite or clay mineral reactions that might have occurred at or near the time of sedimentation and diagenesis were not sufficient to reset the K-Ar and Rb-Sr systematics of the clay minerals. Further, x-ray data indicate a normal evaporitic assemblage of clay minerals and Fe-rich oxyhydroxide phases. The clay minerals and other insoluble material appear to be resistant to the destructive effects of their entrapment in the evaporites, which suggests that these insoluble materials would be good getters for any radionuclides (hypothetically) released from the storage of radioactive wastes in the area.

  18. PANI-Ag-Cu Nanocomposite Thin Films Based Impedimetric Microbial Sensor for Detection of E. coli Bacteria

    Directory of Open Access Journals (Sweden)

    Huda Abdullah

    2014-01-01

    Full Text Available PANI-Ag-Cu nanocomposite thin films were prepared by sol-gel method and deposited on the glass substrate using spin coating technique. Polyaniline was synthesized by chemical oxidative polymerization of aniline monomer in the presence of nitric acid. The films were characterized using XRD, FTIR, and UV-Visible spectroscopy. The performance of the sensor was conducted using electrochemical impedance spectroscopy to obtain the change in impedance of the sensor film before and after incubation with E. coli bacteria in water. The peaks in XRD pattern confirm the presence of Ag and Cu nanoparticles in face-centered cubic structure. FTIR analysis shows the stretching of N–H in the polyaniline structure. The absorption band from UV-Visible spectroscopy shows high peaks between 400 nm and 500 nm which indicate the presence of Ag and Cu nanoparticles, respectively. Impedance analysis indicates that the change in impedance of the films decreases with the presence of E. coli. The sensitivity on E. coli increases for the sample with high concentration of Cu.

  19. The Messinian evaporites in the Levant Basin: lithology, deformation and its evolution

    Science.gov (United States)

    Feng, Ye; Steinberg, Josh; Reshef, Moshe

    2017-04-01

    The lithological composition of the Messinian evaporite in the Levant Basin remains controversial and salt deformation mechanisms are still not fully understood, due to the lack of high resolution 3D depth seismic data and well logs that record the entire evaporite sequence. We demonstrate how 3D Pre-stack depth migration (PSDM) and intra-salt tomography can lead to improved salt imaging. Using 3D PSDM seismic data with great coverage and deepwater well log data from recently drilled boreholes, we reveal intra-salt reflective units associated with thin clastic layers and a seismic transparent background consisting of uniform pure halite. Structural maps of all internal reflectors are generated for stratigraphy and attributes analysis. High amplitude fan structures in the lowermost intra-salt reflector are observed, which may indicate the source of the clastic formation during the Messinian Salinity Crisis (MSC). The Messinian evaporite in the Levant Basin comprises six units; the uppermost unit thickens towards the northwest, whereas the other units are uniform in thickness. The top of salt (TS) horizon is relatively horizontal, while all other intra-salt reflectors and base of salt (BS) dip towards the northwest. Different seismic attributes are used for identification of intra-salt deformation patterns. Maximum curvature maps show NW-striking thrust faults on the TS and upper intra-salt units, and dip azimuth maps are used to show different fold orientations between the TS and intra-salt units, which indicate a two-phase deformation mechanism: basin NW tilting as syn-depositional phase and NNE spreading of Plio-Pleistocene overburden as post-depositional phase. RMS amplitude maps are used to identify a channelized system on the TS. An evaporite evolution model during the MSC of the Levant Basin is therefore established based on all the observations. Finally the mechanical properties of the salts will be utilized to explore salt deformation in the Levant Basin

  20. Whey protein isolate/cellulose nanofibre/TiO2 nanoparticle/rosemary essential oil nanocomposite film: Its effect on microbial and sensory quality of lamb meat and growth of common foodborne pathogenic bacteria during refrigeration.

    Science.gov (United States)

    Alizadeh Sani, Mahmood; Ehsani, Ali; Hashemi, Mohammad

    2017-06-19

    The use of biodegradable nanocomposite films in active packaging is of great importance since they can have a controlled release of antimicrobial compounds. This study was conducted to evaluate the efficacy of whey protein isolate (WPI)/cellulose nanofibre (CNF) nanocomposite films containing 1.0% (w/w) titanium dioxide (TiO2) and 2.0% (w/v) rosemary essential oil (REO) in preserving the microbial and sensory quality of lamb meat during the storage at 4±1°C. Initially, the best concentration of each compound to be added to the film was determined by micro-dilution and disc diffusion methods. The microbial and sensory properties of lamb meat were controlled in two groups (control and treatment) over 15days of storage. Then, the samples were analysed for total viable count (TVC), Pseudomonas spp. count, Enterobacteriaceae count, Lactic acid bacteria (LAB) count, inoculated Staphylococcus aureus count, Listeria monocytogenes count, and Escherichia coli O157:H7 count. Microbial analysis and nine-point hedonic scale was applied for the sensory analysis. Results indicated that the use of nanocomposite films significantly reduced the bacterial counts of treatment group. Higher inhibition effect was observed on Gram-positive bacteria than on Gram-negative bacteria (Pmeat (15days) compared to the control meat (6days). Based on the results of this study, the edible nanocomposite films were effective in preserving the microbial and sensory qualities of lamb meat; therefore, this application is recommended in meat especially red meat. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Characteristics and geological significance of Re-Os isotopic system of evaporites in Mboukoumassi deposit, the Republic of Congo

    Science.gov (United States)

    Zhao, Xianfu; Wang, Zongqi; Liu, Chenglin; Li, Chao; Jiao, Pengcheng; Zhao, Yanjun; Zhang, Fan

    2018-02-01

    Evaporite dating has been an open problem. The study investigates the Re-Os isotopic system in the organic-rich sedimentary rocks to constrain the infilling of sedimentary basin and related geological events. In the Mboukoumassi potash deposit in the Republic of Congo (Congo-Brazzaville) in West Africa, several layers of organic-rich dark shale were found in the evaporite series. Through drilling core, the dark shale in the evaporite is found to satisfy the requirements of Re-Os isotope test. The result shows that the Re-Os isochron age of the dark shale in the study area ranges from 78.7 ± 1.1 to 96 ± 7 Ma, which is the first precise age of the Mboukoumassi potash deposit in the Republic of Congo (Congo-Brazzaville), West Africa. Therefore, the age of deposition of this set of evaporite may be Cenomanian-Turonian, which is younger than the age previously thought (around 113-125Ma, Aptian). The Re-Os isotopic dating technique used for the pioneering study on the precise dating of the Mboukoumassi potash deposit provides a new approach to the study of the sedimentary age of ancient evaporite deposits. The initial 187Os/188Os value decreasing from 2.02 ± 0.21 to 0.982 ± 0.03 for the core sample reflects the source rock chang along the core, and this is consistent with the geological evolution of the basin.

  2. The geochemical and isotopic record of evaporite recycling in spas and salterns of the Basque Cantabrian basin, Spain

    Energy Technology Data Exchange (ETDEWEB)

    Iribar, V., E-mail: vicente.iribar@ehu.es [Departamento de Geodinamica, Universidad del Pais Vasco, PO Box 644, E-48080 Bilbao (Spain); Abalos, B. [Departamento de Geodinamica, Universidad del Pais Vasco, PO Box 644, E-48080 Bilbao (Spain)

    2011-08-15

    Graphical abstract: Stable isotopes and hydrochemistry disclose two types of saline groundwater whose source is the dissolution of Triassic (Keuper) or Cretaceous (Wealden) evaporites, that are recycled from the older ones. Display Omitted Highlights: > Saline springs compositions are used to delineate extent of subsurface evaporites. > Origin of Wealden vs. Triassic evaporites constrained using {delta}{sup 34}S{sub SO4}, {delta}{sup 18}O{sub SO4} and Cl/Br ratio. > Geological structures and saline water circulation relation. - Abstract: Evaporite outcrops are rare in the Basque Cantabrian basin due to a rainy climate, but saline springs with total dissolved solids ranging from 0.8 to 260 g/L are common and have long been used to supply spas and salterns. New and existing hydrochemistry of saline springs are used to provide additional insight on the origin and underground extent of their poorly known source evaporites. Saline water hydrochemistry is related to dissolution of halite and gypsum from two evaporitic successions (Triassic 'Keuper' and Lower Cretaceous 'Wealden'), as supported by rock samples from outcrops and oil exploration drill cuttings. The {delta}{sup 34}S value of gypsum in the Keuper evaporites and sulfate in the springs is {delta}{sup 34}S{sub SO4} = 14.06 {+-} 1.07 per mille and {delta}{sup 18}O{sub SO4} = 13.41 {+-} 1.44 per mille, and the relationship between Cl/Br ratio of halite and water shows that waters have dissolved halite with Br content between 124 and 288 ppm. The {delta}{sup 34}S value of gypsum in the Wealden evaporites and sulfate in the springs is {delta}{sup 34}S{sub SO4} = 19.66 {+-} 1.76 per mille, {delta}{sup 18}O{sub SO4} = 14.93 {+-} 2.35 per mille, and the relationship between Cl/Br ratio of halite and water shows that waters have dissolved halite with Br content between 15 and 160 ppm. Wealden evaporites formed in a continental setting after the dissolution of Keuper salt. Gypsum {delta}{sup 34}S

  3. Identification, prediction, and mitigation of sinkhole hazards in evaporite karst areas

    Science.gov (United States)

    Gutierrez, F.; Cooper, A.H.; Johnson, K.S.

    2008-01-01

    Sinkholes usually have a higher probability of occurrence and a greater genetic diversity in evaporite terrains than in carbonate karst areas. This is because evaporites have a higher solubility and, commonly, a lower mechanical strength. Subsidence damage resulting from evaporite dissolution generates substantial losses throughout the world, but the causes are only well understood in a few areas. To deal with these hazards, a phased approach is needed for sinkhole identification, investigation, prediction, and mitigation. Identification techniques include field surveys and geomorphological mapping combined with accounts from local people and historical sources. Detailed sinkhole maps can be constructed from sequential historical maps, recent topographical maps, and digital elevation models (DEMs) complemented with building-damage surveying, remote sensing, and high-resolution geodetic surveys. On a more detailed level, information from exposed paleosubsidence features (paleokarst), speleological explorations, geophysical investigations, trenching, dating techniques, and boreholes may help in investigating dissolution and subsidence features. Information on the hydrogeological pathways including caves, springs, and swallow holes are particularly important especially when corroborated by tracer tests. These diverse data sources make a valuable database-the karst inventory. From this dataset, sinkhole susceptibility zonations (relative probability) may be produced based on the spatial distribution of the features and good knowledge of the local geology. Sinkhole distribution can be investigated by spatial distribution analysis techniques including studies of preferential elongation, alignment, and nearest neighbor analysis. More objective susceptibility models may be obtained by analyzing the statistical relationships between the known sinkholes and the conditioning factors. Chronological information on sinkhole formation is required to estimate the probability of

  4. Possible evaporite karst in an interior layered deposit in Juventae Chasma, Mars

    Directory of Open Access Journals (Sweden)

    Davide Baioni

    2017-06-01

    Full Text Available This paper describes karst landforms observed in an interior layered deposit (ILD located within Juventae Chasma a trough of the Valles Marineris, a rift system that belongs to the Tharsis region of Mars. The ILD investigated is characterized by spectral signatures of kieserite, an evaporitic mineral present on Earth. A morphologic and morphometric survey of the ILD surface performed on data of the Orbiter High Resolution Imaging Science Experiment (HiRISE highlighted the presence of depressions of various shapes and sizes. These landforms interpreted as dolines resemble similar karst landforms on Earth and in other regions of Mars. The observed karst landforms suggest the presence of liquid water, probably due to ice melting, in the Amazonian age.

  5. A halite-siderite-anhydrite-chlorapatite assemblage in Nakhla: mineralogical evidence for evaporites on Mars

    Science.gov (United States)

    Bridges, J. C.; Grady, M. M.

    1999-05-01

    We report the results of a study of a halite-siderite-anhydrite-chlorapatite assemblage in the SNC (martian) meteorite Nakhla. These minerals are found associated with each other in interstitial areas, halite often being adjacent to or enclosing siderite. We suggest the halite and other minerals are martian in origin because the conditions of fall preclude significant amounts of terrestrial contamination or weathering having taken place; textures indicate that the minerals within this assemblage crystallised at the same stage as some silicate and oxide minerals within the Nakhla parent ; the association with siderite which previous studies have shown has carbon and oxygen isotopic compositions incompatible with an origin on Earth. Siderite has the range of compositions CaCO3 0.1-5.7, MgCO3 2.0-40.9, FeCO3 23.2-87.0, MnCO3 1.0-39.9 mol. %. There are two compositional groupings: high-MnCO3 (( 30 mol %) and low-MnCO3/high-FeCO3, with a gap identified between the two. This may be a miscibility gap or, alternatively, the 2 compositional groupings may mark separate generations of carbonate. We have not found any textural evidence for the latter explanation but acceptance of the presence of a miscibility gap would require independent work on Fe-Mn carbonates to verify its existence. Trace element abundances have been determined by ion microprobe analysis on 3 siderite and 1 anhydrite grains. Siderite has LREE (2.2 - 7.3 x C1) > HREE (0.32 - 0.79 x C1) without Ce or Eu anomalies and the anhydrite has a similar pattern. These abundances reflect the source composition rather than partitioning or complexing controls. They are not typical of hydrothermal signatures which generally do not have such smooth REE abundance patterns. The nature of the mineral assemblage suggests that its source rocks on Mars were evaporites. These may be common in the craters and flood plains of the martian southern highlands. Two models are suggested in this paper to explain the incorporation of

  6. Integrated stratigraphy and chronology of Messinian evaporites from the Levant basin in the deep eastern Mediterranean

    Science.gov (United States)

    Meilijson, Aaron; Steinberg, Josh; Hilgen, Frits; Bialik, Or; Ilner, Peter; Waldmann, Nicolas; Makovsky, Yizhaq

    2017-04-01

    The Messinian salinity crisis (MSC) is perceived as an environmental crisis governed by climatic and tectonic controls, affecting global oceans salinity and shaping the Mediterranean's bio-chemical composition. The elaborate and ongoing study of the Mediterranean MSC is mainly focused on marginal and intermediate sections from which material was previously available. This relatively proximal data is also coupled with offshore seismic data and several wells which have penetrated the deep-basin Messinian salt in its uppermost parts, for producing stratigraphic models and hypotheses related to the distal occurrence of the MSC. These offshore assumptions could only be tested by drilling in the deep Mediterranean Sea. In this work we investigate these fascinating deposits from previously inaccessible domains in the deepest realms of the Mediterranean, and correlate this data with the much more abundant and elaborate findings reported from the marginal and intermediate depositional environments. Here we provide for the first time high resolution sedimentological, faunal and geochemical data from the entire massive Messinian evaporite section of the deep Eastern Mediterranean basin. We have analyzed an extensive set of well cuttings while correlating results to well logs and seismic data, and constructed a chronostratigraphic model based on biostratigraphy and astrochronology. We present a detailed account of the pre- and evaporitic Messinian as it occurred in the deep Levant basin, identifying paleo life in the form of diatoms, foraminifera and ostracods within different parts of the section. Our results indicate that salt was deposited during the complete 640 kyr-long MSC, rather than limited to the 50 kyr (stage 2) MSC acme. Moreover, the deep-basin was barren of eukaryotic life throughout most of this duration, at least in the Levant. Thus brine formation, salt precipitation and faunal extinction took place in a non-desiccated basin, having a restricted but often open

  7. Recharged or modified-connate water in a carbonate bed within an evaporite aquitard, Texas panhandle

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, A.R.; Kreitler, C.W.

    1985-01-01

    Hydraulic-head data and numerical modeling suggest that ground water in the Palo Duro Basin area of the Texas Panhandle has leaked downward through a Permian evaporite-carbonate-shale aquitard. Chemical composition of brine in a carbonate bed of the San Andres Formation within the aquitard gives ambiguous evidence of ground-water leakage. San Andres ground water varies chemically from potable Ca-HCO/sub 3/- and Ca-SO/sub 4/-type waters in the nonhalitic sections of the San Andres Formation below the Pecos Plains of eastern New Mexico to Na-Ca-Cl brine within the Palo Duro Basin. The composition of the 336 to 384 g/L brine can be explained by solution of dolomite, anhydrite, and halite, accompanied by exchange of some sodium for calcium. The brine is near oxygen isotopic equilibrium with San Andres dolomite. Problems with this recharged-water explanation are identification of the water-rock reaction that replaces dissolved sodium with calcium and the reaction that enriches deltaD of San Andres brine by 30 per thousand to 40 per thousand relative to modern regional meteoric water. Problems with explaining San Andres brine as modified-connate water are that hydraulic-head data and numerical modeling suggest leakage occurs and that ion ratios in brine differ from ion ratios in evaporatively concentrated, diagenetically modified seawater. However, because leakage rates are slow and variable, some modified-connate brine could be mixed with leaking recharged water, making interpretation difficult. Leakage rate and extent of flushing of old brine depend on whether flow is through fractures or through intergranular pore space in the evaporite aquitard.

  8. Thickness of Jurassic evaporite facies in the Afghan-Tajik and Amu Darya basins of northern Afghanistan and adjacent areas (evapisoafg.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This shapefile contains polylines (isopachs) that describe the thickness of Jurassic age evaporite facies (Gaurdak formation) in the Afghan-Tajik and Amu Darya basins

  9. Jurassic evaporite facies of the Afghan-Tajik and Amu Darya basins in northern Afghanistan and adjacent areas (evapfacafg.shp)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This shapefile contains polygons that describe the spatial extent of Jurassic age evaporite facies (Gaurdak formation) in the Afghan-Tajik and Amu Darya basins.

  10. Characterization of organic-rich material in an evaporitic environment: the Lower Oligocene of the Mulhouse basin (Alsace, France)

    Science.gov (United States)

    Gely, J.-P.; Blanc-Valleron, M.-M.; Fache-Dany, F.; Schuler, M.; Ansart, M.

    1993-12-01

    Evaporitic sediments from the Max borehole (Mulhouse Potash Basin, southern Rhine Graben) were studied over an interval of about 40 m in the vicinity of sylvite beds. Total organic carbon (TOC) analyses of 450 samples showed that marly layers interbedded within the evaporites have TOC values that fluctuate in a rhythmic manner; the highest values are found near the top of the clay—anhydrite layers and the lowest values are recorded near the top of the halite-rich beds. Geochemical (elemental analysis of kerogen, gas chromatography of bitumen) and palynological studies of 26 samples showed that the organic matter is mainly of algal origin (A and B groups). A third category of organic material (C group) may have been derived from a mixture of continental supply and in situ bacterial productivity.

  11. Contribution of an ancient evaporitic-type reservoir to lake vostok chemistry

    Science.gov (United States)

    de Angelis, M.; Thiemens, M. H.; Savarino, J.; Petit, J. R.

    2003-04-01

    Accretion ice 1 (3538 to 3608 m) contents visible sediment inclusions likely incorporated into ice in a shallow bay upstream Vostok where glacier moves against a relief rise. Ion chromatography measurements indicate that elemental concentrations are linked to inclusions abundances. More than 80% of SO_42- is present as CaSO_4 or MgSO_4. While SO_42- concentrations and the relative proportion of CaSO_4 and MgSO_4 varies in a wide range in accreted ice, concentration profiles of Na and Cl, present as NaCl, are much more regular even along individual crystals. Question rises about the presence of such salts in lake water: The 17O anomaly of sulphate in one samples taken at 3570 m suggests that less than 10% of total sulphate comes from DMS oxidation, ruling out any significant contribution of glacer melt water. Fe concentrations are low (10 ppb) excluding sulphate production from the pyrite oxidation by biogenic in-situ activity. This conclusion is supported by the isotopic signature of 34S. Taken all together, these observations strongly suggest the contribution of an evaporitic-type basin to the lake salinity. Assuming that sediments accumulated in an isolated reservoir prior the lake formation, seismotectonic activated hydrothermal circulation may pulse NaCl rich water with sulphate salts through faults up to their vents in a shallow bay upstream Vostok, where they could be incorporated in the accreted ice and also contribute to lake salinity.

  12. Origin of deformed halite hopper crystals, pseudomorphic anhydrite cubes and polyhalite in Alpine evaporites (Austria, Germany).

    Science.gov (United States)

    Leitner, C; Neubauer, F; Marschallinger, R; Genser, J; Bernroider, M

    The Alpine Haselgebirge Formation represents an Upper Permian to Lower Triassic evaporitic rift succession of the Northern Calcareous Alps (Eastern Alps). Although the rocksalt body deposits are highly tectonised, consisting mainly of protocataclasites and mylonites of halite and mudrock, the early diagenetic history can be established from non-tectonised mudrock bodies: Cm-sized euhedral halite hopper crystals formed as displacive cubes within mud just during shallow burial. The crystals were deformed by subsequent compaction. Later, migrating fluids led to the replacement of halite by anhydrite retaining the shapes of deformed halite cubes. Polyhalite formed from subsequent enhanced fluid migration. Mudrock provided water by dewatering, while potassium and magnesium were dissolved from primary salt minerals. When these fluids interacted with sulphates, polyhalite precipitated. 40Ar/39Ar analyses date the polyhalite from within the retaining shapes of deformed halite hopper-shaped cubes from two localities to ca. 235-232 Ma (Middle Triassic). At this time, ca. 20-25 Ma after sedimentation, polyhalite crystallised at shallow levels.

  13. A co-crystal between benzene and ethane: a potential evaporite material for Saturn's moon Titan

    Directory of Open Access Journals (Sweden)

    Helen E. Maynard-Casely

    2016-05-01

    Full Text Available Using synchrotron X-ray powder diffraction, the structure of a co-crystal between benzene and ethane formed in situ at cryogenic conditions has been determined, and validated using dispersion-corrected density functional theory calculations. The structure comprises a lattice of benzene molecules hosting ethane molecules within channels. Similarity between the intermolecular interactions found in the co-crystal and in pure benzene indicate that the C—H...π network of benzene is maintained in the co-crystal, however, this expands to accommodate the guest ethane molecules. The co-crystal has a 3:1 benzene:ethane stoichiometry and is described in the space group R\\bar 3 with a = 15.977 (1 Å and c = 5.581 (1 Å at 90 K, with a density of 1.067 g cm−3. The conditions under which this co-crystal forms identify it is a potential that forms from evaporation of Saturn's moon Titan's lakes, an evaporite material.

  14. Volcanic sequence in Late Triassic – Jurassic siliciclastic and evaporitic rocks from Galeana, NE Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Cruz-Gómez, E.M.; Velasco-Tapia, F.; Ramírez-Fernández, J.A.; Jenchen, U.; Rodríguez-Saavedra, P.; Rodríguez-Díaz, A.A.; Iriondo, A.

    2017-11-01

    In northeastern Mexico, volcanic rocks interbedded with Late Triassic–Jurassic siliciclastic and evaporitic strata have been linked to magmatic arcs developed in the Pangea western margin during its initial phase of fragmentation. This work provides new petrographic and geochemical data for volcanism included in the El Alamar and Minas Viejas formations outcropping in the Galeana region. Andesitic dykes and sills (n= 10) in the El Alamar redbeds show SiO2= 47.5–59.1% and MgO= 1.2–4.2%, as well as a geochemical affinity to island arc magmas. This work represents the first report of this tectonic setting in the region. Geological and petrographic evidence suggest that this arc system likely developed after ~220 and before ~193Ma. Trachy-andesitic and rhyodacitic domes (n= 20) associated with the Minas Viejas gypsum-carbonates sequence show SiO2= 61.8–82.7% and MgO= 0.1–4.0% with a tectonic affinity to continental arc. A rhyodacite sample from this region has been dated by U-Pb in zircon, yielding an age of 149.4 ± 1.2Ma (n= 21), being the youngest age related to this arc. Finally, we propose a threestep model to explain the tectonic evolution from Late Triassic island arc to Jurassic continental arc system in the northeastern Mexico.

  15. Geochemical impacts of groundwater heat pump systems in an urban alluvial aquifer with evaporitic bedrock.

    Science.gov (United States)

    Garrido Schneider, Eduardo A; García-Gil, Alejandro; Vázquez-Suñè, Enric; Sánchez-Navarro, José Á

    2016-02-15

    In the last decade, there has been an extensive use of shallow geothermal exploitations in urban environments. Although the thermal interference between exploitations has been recently studied, there is a lack of knowledge regarding the geochemical impacts of those systems on the aquifers where they are installed. Groundwater flow line scale and well-doublet scale research work has been conducted at city scale to quantify the geochemical interaction of shallow geothermal exploitations with the environment. A comprehensive analysis was conducted on data obtained from a monitoring network specifically designed to control and develop aquifer policies related to thermal management of the aquifer. The geochemical impacts were evaluated from a thermodynamic point of view by means of saturation index (SI) calculations with respect to the different mineral species considered in the system. The results obtained indicate limited geochemical interaction with the urban environment in most of the situations. However, there are some cases where the interaction of the groundwater heat pump installations with the evaporitic bedrock resulted in the total disablement of the exploitation system operation wells. The application of the tool proposed proved to be pragmatic in the evaluation of geochemical impacts. Injection of water into the aquifer can trigger an important bedrock gypsum and halite dissolution process that is partly responsible for scaling in well casing pipes and collapse of the terrain in the vicinity of injection wells. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Estimating Rheological Parameters of Anhydrite from Folded Evaporite sequences: Implications for Internal Dynamics of Salt Structure

    Science.gov (United States)

    Adamuszek, Marta; Dabrowski, Marcin; Schmalholz, Stefan M.; Urai, Janos L.; Raith, Alexander

    2015-04-01

    Salt structures have been identified as a potential target for hydrocarbon, CO2, or radioactive waste storage. The most suitable locations for magazines are considered in the thick and relatively homogeneous rock salt layers. However, salt structures often consist of the evaporite sequence including rock salt intercalated with other rock types e.g.: anhydrite, gypsum, potassium and magnesium salt, calcite, dolomite, or shale. The presence of such heterogeneities causes a serious disturbance in the structure management. Detailed analysis of the internal architecture and internal dynamics of the salt structure are crucial for evaluating them as suitable repositories and also their long-term stability. The goal of this study is to analyse the influence of the presence of anhydrite layers on the internal dynamics of salt structures. Anhydrite is a common rock in evaporite sequences. Its physical and mechanical properties strongly differ from the properties of rock salt. The density of anhydrite is much higher than the density of salt, thus anhydrite is likely to sink in salt causing the disturbance of the surrounding structures. This suggestion was the starting point to the discussion about the long-term stability of the magazines in salt structures [1]. However, the other important parameter that has to be taken into account is the viscosity of anhydrite. The high viscosity ratio between salt and anhydrite can restrain the layer from sinking. The rheological behaviour of anhydrite has been studied in laboratory experiments [2], but the results only provide information about the short-term behaviour. The long-term behaviour can be best predicted using indirect methods e.g. based on the analysis of natural structures that developed over geological time scale. One of the most promising are fold structures, the shape of which is very sensitive to the rheological parameters of the deforming materials. Folds can develop in mechanically stratified materials during layer

  17. Geochemical impacts of groundwater heat pump systems in an urban alluvial aquifer with evaporitic bedrock

    Energy Technology Data Exchange (ETDEWEB)

    Garrido Schneider, Eduardo A. [Geological Survey of Spain (IGME), C/ Manuel Lasala no. 44, 9B, 50006 Zaragoza (Spain); García-Gil, Alejandro, E-mail: agargil@unizar.es [Department of Earth Sciences, University of Zaragoza, C/ Pedro Cerbuna 12, 50009 Zaragoza (Spain); GHS, Institute of Environmental Assessment & Water Research (IDAEA), CSIC, Jordi Girona 18–26, 08034 Barcelona (Spain); Vázquez-Suñè, Enric [GHS, Institute of Environmental Assessment & Water Research (IDAEA), CSIC, Jordi Girona 18–26, 08034 Barcelona (Spain); Sánchez-Navarro, José Á. [Department of Earth Sciences, University of Zaragoza, C/ Pedro Cerbuna 12, 50009 Zaragoza (Spain)

    2016-02-15

    In the last decade, there has been an extensive use of shallow geothermal exploitations in urban environments. Although the thermal interference between exploitations has been recently studied, there is a lack of knowledge regarding the geochemical impacts of those systems on the aquifers where they are installed. Groundwater flow line scale and well-doublet scale research work has been conducted at city scale to quantify the geochemical interaction of shallow geothermal exploitations with the environment. A comprehensive analysis was conducted on data obtained from a monitoring network specifically designed to control and develop aquifer policies related to thermal management of the aquifer. The geochemical impacts were evaluated from a thermodynamic point of view by means of saturation index (SI) calculations with respect to the different mineral species considered in the system. The results obtained indicate limited geochemical interaction with the urban environment in most of the situations. However, there are some cases where the interaction of the groundwater heat pump installations with the evaporitic bedrock resulted in the total disablement of the exploitation system operation wells. The application of the tool proposed proved to be pragmatic in the evaluation of geochemical impacts. Injection of water into the aquifer can trigger an important bedrock gypsum and halite dissolution process that is partly responsible for scaling in well casing pipes and collapse of the terrain in the vicinity of injection wells. - Highlights: • We studied geochemical impacts of groundwater heat pump systems. • We have sampled a monitoring network in an energetically exploited urban aquifer. • A limited geochemical interaction has been found in most of the exploitations. • Reinjection into the aquifer produces an important bedrock gypsum dissolution. • Scaling in well casing pipes and collapse of the terrain have been observed.

  18. Evaporites as a source for oil. Progress report, November 15, 1988--November 15, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Schreiber, B.C.; Benalihioulhaj, S. [Queens Coll., Flushing, NY (United States). Dept. of Geology; Philp, R.P. [Oklahoma Univ., Norman, OK (United States). School of Geology and Geophysics

    1993-02-01

    Organic matter, present in some sediments, acts as the source for hydrocarbons and has been studied at great length, but organic-rich sediments from hypersaline environments are just beginning to be understood. Many types of organic matter from such restricted environments have been identified, and in this study their maturation pathways and products are being explored. By collecting biologically-identified organic matter produced within modern evaporative environments from a number of different marine and nonmarine settings and carrying out detailed geochemical examination of samples we are gradually beginning to understand these materials. The organic samples collected were from evaporative marine, sabkha, and lacustrine deposits, and have been subjected to two types of artificial maturation, hydrous and confined pyrolysis, over a fairly wide range of temperatures (1500 to 350{degrees}C). The biomarker products of these treatments are being analyzed and followed in great detail. Analyses of saturate and aromatic hydrocarbons as well as sulfur compounds in the original and the matured samples provide a comprehensive view of the biomarker assemblages associated with these different depositional environments at different stages of maturity. Infrared spectroscopy and Rock Eval pyrolysis of both the isolated kerogens from both the original and pyrolyzed samples has permitted us to clearly characterize the functional groupings on the one hand and the free hydrocarbons, the potential hydrocarbons, and the oxygenated compounds on the other hand. We have thus been able to demonstrate the potential of the organic matter associated with the different evaporitic environments to act as a good source for oil generation.

  19. Optimized Use of the MALDI BioTyper System and the FilmArray BCID Panel for Direct Identification of Microbial Pathogens from Positive Blood Cultures.

    Science.gov (United States)

    Fiori, B; D'Inzeo, T; Giaquinto, A; Menchinelli, G; Liotti, F M; de Maio, F; De Angelis, G; Quaranta, G; Nagel, D; Tumbarello, M; Posteraro, B; Sanguinetti, M; Spanu, T

    2016-03-01

    Despite the current reliance on blood cultures (BCs), the diagnosis of bloodstream infections (BSIs) can be sped up using new technologies performed directly on positive BC bottles. Two methods (the MALDI BioTyper system and FilmArray blood culture identification [BCID] panel) are potentially applicable. In this study, we performed a large-scale clinical evaluation (1,585 microorganisms from 1,394 BSI episodes) on the combined use of the MALDI BioTyper and FilmArray BCID panel compared to a reference (culture-based) method. As a result, the causative organisms of 97.7% (1,362/1,394) of the BSIs were correctly identified by our MALDI BioTyper and FilmArray BCID-based algorithm. Specifically, 65 (5.3%) out of 1,223 monomicrobial BCs that provided incorrect or invalid identifications with the MALDI BioTyper were accurately detected by the FilmArray BCID panel; additionally, 153 (89.5%) out of 171 polymicrobial BCs achieved complete identification with the FilmArray BCID panel. Conversely, full use of the MALDI BioTyper would have resulted in the identification of only 1 causative organism in 97/171 (56.7%) of the polymicrobial cultures. By applying our diagnostic algorithm, the median time to identification was shortened (19.5 h versus 41.7 h with the reference method; P FilmArray BCID panel led to a significant cost savings. Twenty-six out of 31 microorganisms that could not be identified were species/genera not designed to be detected with the FilmArray BCID panel, indicating that subculture was not dispensable for a few of our BSI episodes. In summary, the fast and effective testing of BC bottles is realistically adoptable in the clinical microbiology laboratory workflow, although the usefulness of this testing for the management of BSIs remains to be established. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  20. An evaporite-based high-resolution sulfur isotope record of Late Permian and Triassic seawater sulfate

    Science.gov (United States)

    Bernasconi, Stefano M.; Meier, Irene; Wohlwend, Stephan; Brack, Peter; Hochuli, Peter A.; Bläsi, Hansruedi; Wortmann, Ulrich G.; Ramseyer, Karl

    2017-05-01

    Variations in the sulfur isotope composition of dissolved marine sulfate through time reflect changes in the global sulfur cycle and are intimately related to changes in the carbon and oxygen cycles. A large shift in the sulfur isotope composition of sulfate at the Permian/Triassic boundary has been recognized for long time and a number of studies were carried out to understand the causes and significance of this shift. However, data for the Middle and Late Triassic are very sparse and the stratigraphic evolution of the sulfur isotope composition of seawater is poorly constrained due to the small number of samples analyzed and/or due to the limited stratigraphic intervals studied. Moreover, in the last few years the Triassic timescale has significantly changed due to a wealth of new radiometric and stratigraphic data. In this study we show that for the Late Permian and the Triassic it is possible to obtain a precise reconstruction of the evolution of the sulfur cycle, for parts of it at sub-million year resolution, by analyzing exclusively gypsum and anhydrite deposits. We base our reconstruction on new data from the Middle and Late Triassic evaporites of Northern Switzerland and literature data from evaporites from Germany, Austria, Italy and the Middle East. We propose a revised correlation between the well-dated marine Tethyan sections in northern Italy and the evaporites from Northern Switzerland and from the Germanic Basin calibrated to the newest radiometric absolute age scale. This new correlation allows for a precise dating of the evaporites and constructing a composite sulfur isotope evolution of seawater sulfate from the latest Permian (Lopingian Epoch) to the Norian. We show that a rapid positive shift of approximately 24‰ at the Permian-Triassic boundary can be used to constrain seawater sulfate concentrations in the range of 2-6 mM, thus higher than previous estimates but with less rapid changes. Finally, we discuss two possible evolution scenarios

  1. Enriching particles on a bubble through drainage: Measuring and modeling the concentration of microbial particles in a bubble film at rupture

    Directory of Open Access Journals (Sweden)

    Peter L. L. Walls

    2017-06-01

    Full Text Available The concentration of microbes and other particulates is frequently enriched in the droplets produced by bursting bubbles. As a bubble rises to the ocean surface, particulates in the bulk liquid can be transported to the sea surface microlayer by attaching to the bubble’s interface. When the bubble eventually ruptures, a fraction of these particulates is often ejected into the surroundings in film droplets with a particulate concentration that is higher than in the liquid from which they formed. The precise mechanisms responsible for this enrichment are unclear, yet such enrichment at the ocean surface influences important exchange processes with the atmosphere. Here we provide evidence that drainage, coupled with scavenging, is responsible for the enrichment. By simultaneously recording the drainage and rupture effects with high-speed and standard photography, we directly measured the particulate concentrations in the thin film of a bubble cap at the moment before it ruptures. We observed that the enrichment factor strongly depends on the film thickness at rupture, and developed a physical model, based on scavenging and drainage, that is consistent with our observations. We have also demonstrated that this model is quantitatively consistent with prior observations of film drop enrichment, indicating its potential for a broader range of applications in the study of the sea surface microlayer and related phenomena.

  2. Performance of the FilmArray® blood culture identification panel utilized by non-expert staff compared with conventional microbial identification and antimicrobial resistance gene detection from positive blood cultures.

    Science.gov (United States)

    McCoy, Morgan H; Relich, Ryan F; Davis, Thomas E; Schmitt, Bryan H

    2016-07-01

    Utilization of commercially available rapid platforms for microbial identification from positive blood cultures is useful during periods of, or in laboratories with, limited expert staffing. We compared the results of the FilmArray® BCID Panel performed by non-expert technologists to those of conventional methods for organism identification performed by skilled microbiologists. Within 8 h of signalling positive by a continuous monitoring blood culture system, positive bottles were analysed by the FilmArray BCID Panel. Data from these analyses were compared to standard-of-care testing, which included conventional and automated methods. To gauge the ease of use of the BCID Panel by non-expert staff, technologists unfamiliar with diagnostic bacteriology performed the testing without prior knowledge of the Gram stain results, or even whether organisms were detected. Identifications of 172/200 (86 %) positive blood cultures using the BCID Panel were consistent with identifications provided by standard-of-care methods. Standard-of-care testing identified organisms in 20 positive blood cultures, which were not represented on the BCID Panel. Seven (3.5 %) blood cultures demonstrated a discrepancy between the methods, which could not be attributed to either a lack of representation on the panel or unclear separate detection of organisms in a mixed blood culture of a shared genus or grouping of organisms, e.g. Staphylococcus or Enterobacteriaceae . One (0.5 %) blood culture yielded invalid results on two separate panels, so it was eliminated from the study. The easy-to-use FilmArray® technology shows good correlation with blood culture identification and antibiotic resistance detection performed by conventional methods. This technology may be particularly useful in laboratories with limited staffing or limited technical expertise.

  3. Evaporite caprock integrity: an experimental study of reactive mineralogy and pore-scale heterogeneity during brine-CO2 exposure.

    Science.gov (United States)

    Smith, Megan M; Sholokhova, Yelena; Hao, Yue; Carroll, Susan A

    2013-01-02

    We present characterization and geochemical data from a core-flooding experiment on a sample from the Three Fingers evaporite unit forming the lower extent of caprock at the Weyburn-Midale reservoir, Canada. This low-permeability sample was characterized in detail using X-ray computed microtomography before and after exposure to CO(2)-acidified brine, allowing mineral phase and voidspace distributions to be quantified in three dimensions. Solution chemistry indicated that CO(2)-acidified brine preferentially dissolved dolomite until saturation was attained, while anhydrite remained unreactive. Dolomite dissolution contributed to increases in bulk permeability through the formation of a localized channel, guided by microfractures as well as porosity and reactive phase distributions aligned with depositional bedding. An indirect effect of carbonate mineral reactivity with CO(2)-acidified solution is voidspace generation through physical transport of anhydrite freed from the rock matrix following dissolution of dolomite. The development of high permeability fast pathways in this experiment highlights the role of carbonate content and potential fracture orientations in evaporite caprock formations considered for both geologic carbon sequestration and CO(2)-enhanced oil recovery operations.

  4. Assessment of an enhanced geothermal system targeting the Prairie Evaporite Formation of the Williston Basin in SW Manitoba

    Science.gov (United States)

    Holländer, Hartmut; Niloofar, Firoozy

    2017-04-01

    Canada has a large potential for geothermal energy production. High thermal resources are recognized at the volcanic belt within the Canadian Cordillera due to the difference between the oceanic and the continental heat flux which creates a border with high heat flow (as high as 150°C/km) along the volcanic belt. However, also regions with lower heat flow such as the Western Canadian Sedimentary Basin (WCSB) is of interest for geothermal usage. The Williston Basin as part of the WCSB shows low thermal gradients of 25-40°C/km. The geology and lithology of Williston Basin show the presence of halite, potassium salts and carbonate wedges within the Prairie Evaporite formation. Halite is the mineral form (salt) of sodium chloride (NaCl) which decreases thermal resistance providing paths of heat transfer to the surface and has 2-3 times higher thermal conductivity comparing to other types of minerals. The potential of a proposed enhanced geothermal system (EGS) to provide adequate energy to a 10-megawatt electricity production plant was investigated. Borehole data from the Manitoban part of the Williston Basin were collected, and two numerical models were built. One model was created for Tilston, SW Manitoba and the second at a generic site in southern Saskatchewan. Geology differs between the sites in terms of layer thicknesses and their depths. The geological sequence is identical. Both sites contain the Prairie Evaporite which consists mainly of halite. The low thermal resistance of the Prairie Evaporite is assumed to be the driving force behind a relatively high temperature at a low depth, which translates into a lower drilling cost to reach the desired layer. The Prairie Evaporite Formation is located at the Tilston site at a depth of 1.5 km with a reservoir thickness of 118 m, while the similar generic's reservoir is present at a depth of 3 km. The design suggested a two well system having one injection and one pumping well. Saline formations are impermeable and

  5. Inverse modeling of groundwater flow in the semiarid evaporitic closed basin of Los Monegros, Spain

    Science.gov (United States)

    Samper-Calvete, F. J.; García-Vera, M. A.

    Only minor attention has been given in the past to the study of closed-basin hydrogeology in evaporitic environments, because these basins usually contain poor-quality groundwater. The motivation for hydrogeological research in the Los Monegros area in northeastern Spain was the approval in 1986 of a large irrigation project in the Ebre River basin. The irrigation of 60,000 ha is planned, partly in an evaporitic closed basin containing playa lakes. The project has given rise to environmental concerns. The evaluation of the hydrologic impacts of irrigation requires quantifying properly the hydrogeology of the area. With the available information, a conceptual hydrogeological model was formulated that identifies two main aquifers connected through a leaky aquitard. On the basis of the conceptual model, a numerical model was calibrated under steady-state conditions using the method of maximum-likelihood automatic parameter estimation (Carrera and Neuman, 1986a). The calibrated model reproduces the measured hydraulic heads fairly well and is consistent with independent information on groundwater discharge. By the solution of the inverse problem, reliable parameter estimates were obtained. It is concluded that anisotropy plays a major role in some parts of the lower aquifer. The geometric average of model conductivity is almost two orders of magnitude larger than the average conductivity derived from small-scale field tests. This scale effect in hydraulic conductivity is consistent with the findings of Neuman (1994) and Sánchez-Vila et al. (1996). Résumé Dans le passé, on s'est peu intéresséà l'hydrogéologie des bassins fermés en milieu évaporitique, parce que ces bassins possèdent en général de l'eau souterraine de qualité médiocre. L'intérêt porté aux recherches hydrogéologiques dans la région de Los Monegros, dans le nord-est de l'Espagne est dûà l'approbation en 1986 d'un vaste projet d'irrigation dans le bassin de l'Ebre. L'irrigation de 60000

  6. Palaeoredox indicators from the organic-rich Messinian early post-evaporitic deposits of the Apennines (Central Italy)

    Science.gov (United States)

    Sampalmieri, G.; Iadanza, A.; Cipollari, P.; Cosentino, D.; Lo Mastro, S.

    2009-04-01

    Bottom redox conditions in marine and lacustrine ancient basins are often inferred by the occurrence of peculiar sedimentological structures and microfaunal assemblages. The co-occurrence, in such environments, of authigenic uranium, framboidal pyrite, barite and Fe-Mn nodules and encrustations, provides a good constraint for palaeo reconstructions. Authigenic uranium is a common constituent of hydrocarbon source rocks: it forms at the sediment-water interface under oxygen-deficient conditions and accumulates together with organic matter (OM). Its precipitation is triggered by the reduction of the soluble U6+ion in seawater to insoluble U4+. With respect to black shales, uranium content has even been used to estimate the TOC. Also authigenic pyrite forms under anoxic conditions and replaces organic matter: 1) the increase in pyrite content and in organic matter are directly correlated; 2) the size distribution of framboidal pyrite (consistent with sulphate-reducing bacterial activity) is considered a measure of redox conditions within the sediment. Barite is an authigenic mineral related to Corg content, since its organic precipitation is triggered by sulphate-reduction processes occurring in decaying OM-bearing microenvironments. Finally, also Fe-Mn oxyhydroxide are typical indicators of redox conditions. About 6 My ago the Mediterranean Sea underwent a giant event of concentration referred to as Messinian Salinity Crisis, which can be roughly subdivided into an evaporitic and a post evaporitic phase. The post evaporitic phase (p-ev; 5.61-5.33 Ma) developed in a context of humid conditions and can be further distinguished into two steps: p-ev1 (early post evaporitic phase) and p-ev2 (late post evaporitic phase). Previous works focused on pev2, which is interpreted to represent the establishment of brackish water conditions (Lago-Mare biofacies). In other respects, the palaeoenvironment of p-ev1 deposits, mostly represented by resedimented evaporitic deposits or

  7. Microbial pesticides

    Science.gov (United States)

    Michael L. McManus

    1991-01-01

    Interest in the use of microbial pesticides has intensified because of public concern about the safety of chemical pesticides and their impact in the environment. Characteristics of the five groups of entomopathogens that have potential as microbial pesticides are briefly discussed and an update is provided on research and development activities underway to enhance the...

  8. McCauley Sinks: A compound breccia pipe in evaporite karst, Holbrook Basin, Arizona, U.S.A

    Science.gov (United States)

    Neal, J.T.; Johnson, K.S.

    2002-01-01

    The McCauley Sinks, in the Holbrook basin of northeastern Arizona, are comprised of some 50 individual sinkholes within a 3-km-wide depression. The sinks are grouped in a semi-concentric pattern of three nested rings. The outer ring is an apparent tension zone containing ring fractures. The two inner rings are semi-circular chains of large sinkholes, ranging up to 100 m across and 50 m deep. Several sub-basins within the larger depression show local downwarping and possible incipient sinkholes. Permian Kaibab Formation limestone is the principal surface lithology; the limestone here is less than 15 m thick and is near its easternmost limit. Although surface rillenkarren are present, and the sinks are seen in the Kaibab limestone outcrops, the Kaibab is mainly a passive rock unit that has collapsed into solution cavities developed in underlying salt beds. Beneath the Kaibab is Coconino Sandstone, which overlies the Permian Schnebly Hill Formation, the unit containing the evaporite rocks-principally halite in the Corduroy Member. Evaporite karst in this part of the Holbrook basin is quite different from the eastern part, probably because of the westward disappearance of the Holbrook anticline, a structure that has major joint systems that help channel water down to the salt beds farther to the east. Also, the McCauley Sinks are near the western limits of the evaporites. The structure at McCauley Sinks suggests a compound breccia pipe, with multiple sinks contributing to the inward-dipping major depression. The Richards Lake depression, 5 km southeast of McCauley Sinks, is similar in form and size but contains only a single, central sinkhole. An apparent difference in hydrogeology at McCauley Sinks is their proximity to the adjacent, deeply incised, Chevelon Canyon drainage, but the hydrologic connections are unknown. The 3-km-wide McCauley Sinks karst depression, along with five other nearby depressions, provide substantial hydrologic catchment. Because of widespread

  9. Effects of current generation and electrolyte pH on reverse salt flux across thin film composite membrane in osmotic microbial fuel cells.

    Science.gov (United States)

    Qin, Mohan; Abu-Reesh, Ibrahim M; He, Zhen

    2016-11-15

    Osmotic microbial fuel cells (OsMFCs) take advantages of synergy between forward osmosis (FO) and microbial fuel cells (MFCs) to accomplish wastewater treatment, current generation, and high-quality water extraction. As an FO based technology, OsMFCs also encounter reverse salt flux (RSF) that is the backward transport of salt ions across the FO membrane into the treated wastewater. This RSF can reduce water flux, contaminate the treated wastewater, and increase the operational expense, and thus must be properly addressed before any possible applications. In this study, we aimed to understand the effects of current generation and electrolyte pH on RSF in an OsMFC. It was found that electricity generation could greatly inhibit RSF, which decreased from 16.3 ± 2.8 to 3.9 ± 0.7 gMH when the total Coulomb production increased from 0 to 311 C. The OsMFC exhibited 45.9 ± 28.4% lower RSF at the catholyte pH of 3 than that at pH 11 when 40 Ω external resistance was connected. The amount of sodium ions transported across the FO membrane was 18.3-40.7% more than that of chloride ions. Ion transport was accomplished via diffusion and electrically-driven migration, and the theoretical analysis showed that the inhibited electrically-driven migration should be responsible for the reduced RSF. These findings are potentially important to control and reduce RSF in OsMFCs or other osmotic-driven processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. The Alpine Haselgebirge Formation, Northern Calcareous Alps (Austria): Permo-Scythian evaporites in an alpine thrust system

    Science.gov (United States)

    Spötl, Christoph

    1989-11-01

    Multiphase-deformed and weakly metamorphosed Permo-Scythian evaporites of the Northern Calcareous Alps (Eastern Alps) of Austria were deposited in an aborted rift arm of the northwest Tethys. They represent marine precipitates laid down in a basin surrounded by alluvial fans and mudflats. Mean bromide values of halite (13 ± 53 ppm) as well as S-isotope ratios of sulphate minerals ( +14 ± 0.9ℵ CDT) indicate that the contribution of non-marine waters to the marine brine composition was insignificant. The most striking feature is the Haselgebirge structure, a chaotic mélange of shales, silt and sandstones, anhydrites, carbonates and scarce magmatites (Kirchner, 1980) embedded in a clayey halite matrix. This mélange resulted from severe tectonization caused by a variety of deformational processes (halokinesis, diapirism, gravitational sliding and alpine thrust tectonics).

  11. Control of Cambrian evaporites on fracturing in fault-related anticlines in the Zagros fold-and-thrust belt

    Science.gov (United States)

    Carminati, Eugenio; Aldega, Luca; Bigi, Sabina; Corrado, Sveva; D'Ambrogi, Chiara; Mohammadi, Peyman; Shaban, Ali; Sherkati, Shahram

    2013-07-01

    Orientation and distribution of fractures in the Oligocene-Early Miocene Asmari Formation (a major reservoir rock of the Zagros petroleum system) were investigated in two anticlines of the Zagros fold-and-thrust belt. The Sim and Kuh-e-Asmari anticlines developed in the areas of the Zagros characterized by the occurrence and absence of Cambrian evaporites at the bottom of the stratigraphic pile, respectively. The aim was to outline major differences in terms of fracture spacing and saturation. Organic matter maturity and clay minerals-based geothermometers suggest that the depth of deformation for the top of the Asmari Formation in the Kuh-e-Asmari anticline was in the range of 1.5-2.7 km assuming a geothermal gradient of 22.5 °C/km. The Asmari Formation in the Sim anticline probably experienced a slightly deeper sedimentary burial (maximum 3 km) with a geothermal gradient of 20 °C/km. The spacing of fractures is generally 2-3 times larger (i.e., strain accommodated by fracturing is smaller) in the Sim anticline than in the Kuh-e-Asmari anticline. This is consistent with regional geological studies, analogue, and numerical models that suggest that thrust faults geometry and related folds are markedly different in the absence or presence of a weak decòllement (evaporites). The larger spacing in the Sim anticline is also consistent with higher temperature predicted for the Asmari Formation in this area. By contrast, the orientation of fractures with respect to the fold axes is the same in both anticlines. The fracture systems are rather immature in both anticlines. The amount and density of fractures in the twofolds are controlled by regional (occurrence/absence of salt and probably different burial), rather than local features (fold geometry).

  12. Marine Microbial Mats and the Search for Evidence of Life in Deep Time and Space

    Science.gov (United States)

    Des Marais, David J.

    2011-01-01

    Cyanobacterial mats in extensive seawater evaporation ponds at Guerrero Negro, Baja California, Mexico, have been excellent subjects for microbial ecology research. The studies reviewed here have documented the steep and rapidly changing environmental gradients experienced by mat microorganisms and the very high rates of biogeochemical processes that they maintained. Recent genetic studies have revealed an enormous diversity of bacteria as well as the spatial distribution of Bacteria, Archaea and Eukarya. These findings, together with emerging insights into the intimate interactions between these diverse populations, have contributed substantially to our understanding of the origins, environmental impacts, and biosignatures of photosynthetic microbial mats. The biosignatures (preservable cells, sedimentary fabrics, organic compounds, minerals, stable isotope patterns, etc.) potentially can serve as indicators of past life on early Earth. They also can inform our search for evidence of any life on Mars. Mars exploration has revealed evidence of evaporite deposits and thermal spring deposits; similar deposits on Earth once hosted ancient microbial mat ecosystems.

  13. Sulfur and strontium isotopic compositions of carbonate and evaporite rocks from the late Neoproterozoic–early Cambrian Bilara Group (Nagaur-Ganganagar Basin, India): Constraints on intrabasinal correlation and global sulfur cycle

    Digital Repository Service at National Institute of Oceanography (India)

    Mazumdar, A.; Strauss, H.

    deposits of terminal Neoproterozoic to early Cambrian age. Lithological and geochemical results suggest the coeval nature of the Bilara Group and Hanseran Evaporite Group. Fluctuations in the sulfur isotopic composition may at least partially be attributed...

  14. Transition from marine deep slope deposits to evaporitic facies of an isolated foreland basin: case study of the Sivas Basin (Turkey)

    Science.gov (United States)

    Pichat, Alexandre; Hoareau, Guilhem; Legeay, Etienne; Lopez, Michel; Bonnel, Cédric; Callot, Jean-Paul; Ringenbach, Jean-Claude

    2017-04-01

    The Sivas Basin, located in the central part of the Anatolian Plateau in Turkey, formed after the closure of the northern Neotethys from Paleocene to Pliocene times. It developed over an ophiolitic basement obducted from the north during the Late Cretaceous. During Paleocene to Eocene times, the onset of the Tauride compression led to the development of a foreland basin affected by north-directed thrusts. The associate general deepening of the basin favored the accumulation of a thick marine turbiditic succession in the foredeep area, followed by a fast shallowing of the basin and thick evaporitic sequence deposition during the late Eocene. We present here the detailed sedimentological architecture of this flysch to evaporite transition. In the northern part of the basin, volcanoclastic turbidites gradually evolved into basinal to prodelta deposits regularly fed by siliciclastic material during flood events. Locally (to the NE), thick-channelized sandstones are attributed to the progradation of delta front distributary channels. The basin became increasingly sediment-starved and evolved toward azoic carbonates and shaly facies, interlayered with organic-rich shales before the first evaporitic deposits. In the southern part of the basin, in the central foredeep, the basinal turbidites become increasingly gypsum-rich and record a massive mega-slump enclosing olistoliths of gypsum and of ophiolitic rocks. Such reworked evaporites were fed by the gravitational collapsing of shallow water evaporites that had previously precipitated in silled piggy-back basins along the southern fold-and-thrust-belt of the Sivas Basin. Tectonic activity that led to the dismantlement of such evaporites probably also contributed to the closure of the basin from the marine domain. From the north to the south, subsequent deposits consist in about 70 meters of secondary massive to fine-grained gypsiferous beds interpreted as recording high to low density gypsum turbidites. Such facies were

  15. Low temperature geothermal systems in carbonate-evaporitic rocks: Mineral equilibria assumptions and geothermometrical calculations. Insights from the Arnedillo thermal waters (Spain).

    Science.gov (United States)

    Blasco, Mónica; Gimeno, María J; Auqué, Luis F

    2018-02-15

    Geothermometrical calculations in low-medium temperature geothermal systems hosted in carbonate-evaporitic rocks are complicated because 1) some of the classical chemical geothermometers are, usually, inadequate (since they were developed for higher temperature systems with different mineral-water equilibria at depth) and 2) the chemical geothermometers calibrated for these systems (based on the Ca and Mg or SO4 and F contents) are not free of problems either. The case study of the Arnedillo thermal system, a carbonate-evaporitic system of low temperature, will be used to deal with these problems through the combination of several geothermometrical techniques (chemical and isotopic geothermometers and geochemical modelling). The reservoir temperature of the Arnedillo geothermal system has been established to be in the range of 87±13°C being the waters in equilibrium with respect to calcite, dolomite, anhydrite, quartz, albite, K-feldspar and other aluminosilicates. Anhydrite and quartz equilibria are highly reliable to stablish the reservoir temperature. Additionally, the anhydrite equilibrium explains the coherent results obtained with the δ18O anhydrite - water geothermometer. The equilibrium with respect to feldspars and other aluminosilicates is unusual in carbonate-evaporitic systems and it is probably related to the presence of detrital material in the aquifer. The identification of the expected equilibria with calcite and dolomite presents an interesting problem associated to dolomite. Variable order degrees of dolomite can be found in natural systems and this fact affects the associated equilibrium temperature in the geothermometrical modelling and also the results from the Ca-Mg geothermometer. To avoid this uncertainty, the order degree of the dolomite present in the Arnedillo reservoir has been determined and the results indicate 18.4% of ordered dolomite and 81.6% of disordered dolomite. Overall, the results suggest that this multi-technique approach

  16. Thrust and fold tectonics and the role of evaporites in deformation in the Western Kuqa Foreland of Tarim Basin, Northwest China

    Energy Technology Data Exchange (ETDEWEB)

    Shuping Chen; Liangjie Tang; Zhijun Jin [University of Petroleum, Beijing (China). Basin and Reservoir Research Center; Key Lab. for Hydrocarbon Accumulation of Education Ministry in Petroleum Univ., Beijing (China); Chengzao Jin [PetroChina Co. Ltd., Beijing (China); Xuejun Pi [Tarim Oilfield Co., PetroChina Co. Ltd., Korla, Xinjiang (China)

    2004-09-01

    The Kuqa foreland between the Tarim basin and the Tianshan Mountains is rich in oil and gas. Based on field work and seismic profiles, the structural styles and their formation mechanisms were determined, and the role of evaporites in the deformation was demonstrated. The main structural styles in the overburden are detachment folds, large scale nappes, triangle zones, gentle and wide synclines, fault-propagation folds and pop-ups. The main structures in the substrate are small-scale thrust faults, duplexes, pop-ups and fault-bend and fault-propagation folds, and formed mainly at the end of the Pliocene under north-south compression. The evaporite layer in the lower section of the Paleogene is the decollement zone for the disharmonic deformations in the overburden and in the substrate. The detachment along the evaporite layer made it possible for compressive stresses to be transmitted farther in the overburden than in the substrate. Deformation in the overburden is more extensive than in the substrate at the leading edge of deformation. At the trailing edge of deformation, the structural highs in the overburden closely correspond to those in the substrate, which is of significance for petroleum exploration in the western Kuqa foreland. (author)

  17. Evaporites and the Salinity of the Ocean During the Phanerozoic: Implications for Climate, Ocean Circulation and Life

    Science.gov (United States)

    Floegel, S.; Hay, W. W.; Migdisov, A.; Balukhovsky, A. N.; Wold, C. N.; Soeding, E.

    2005-12-01

    A compilation of data on volumes and masses of evaporite deposits is used as the basis for reconstruction of the salinity of the ocean in the past. Chloride is tracked as the only ion essentially restricted to the ocean, and past salinities are calculated from reconstructed chlorine content of the ocean. Models for ocean salinity through the Phanerozoic are developed using maximal and minimal estimates of the volumes of existing evaporite deposits, and constant and declining volumes of ocean water through the Phanerozoic. We conclude that there have been significant changes in the mean salinity of the ocean accompanying a general decline throughout the Phanerozoic. The greatest changes are related to major extractions of salt into the ocean basins which developed during the Mesozoic as Pangaea broke apart. Unfortunately, the sizes of these salt deposits are also the least well known. The last major extractions of salt from the ocean occurred during the Miocene, shortly after the large scale extraction of water from the ocean to form the ice cap of Antarctica. However, these two modifications of the masses of H2O and salt in the ocean followed in sequence and did not cancel each other out. Accordingly, salinities during the Early Miocene were reconstructed to be between 37‰ and 39‰. The Mesozoic was a time of generally declining salinity associated with the deep sea salt extractions of the North Atlantic and Gulf of Mexico (Middle to Late Jurassic) and South Atlantic (Early Cretaceous). The earliest of the major extractions of the Phanerozoic occurred during the Permian. There were few large extractions of salt during the earlier Paleozoic. The models suggest that this was a time of relatively stable but slowly increasing salinities ranging through the upper 40‰'s into the lower 50‰'s. Higher salinities for the world ocean had profound consequences for the thermohaline circulation of the ocean in the past. In the modern ocean, with an average salinity of

  18. Evaporite karst geohazards in the Delaware Basin, Texas: review of traditional karst studies coupled with geophysical and remote sensing characterization

    Directory of Open Access Journals (Sweden)

    Kevin W. Stafford

    2017-06-01

    Full Text Available Evaporite karst throughout the Gypsum Plain of west Texas is complex and extensive, including manifestations ranging from intrastratal brecciation and hypogene caves to epigene features and suffosion caves. Recent advances in hydrocarbon exploration and extraction has resulted in increased infrastructure development and utilization in the area; as a result, delineation and characterization of potential karst geohazards throughout the region have become a greater concern. While traditional karst surveys are essential for delineating the subsurface extent and morphology of individual caves for speleogenetic interpretation, these methods tend to underestimate the total extent of karst development and require surficial manifestation of karst phenomena. Therefore, this study utilizes a composite suite of remote sensing and traditional field studies for improved karst delineation and detection of potential karst geohazards within gypsum karst. Color InfraRed (CIR imagery were utilized for delineation of lineaments associated with fractures, while Normalized Density Vegetation Index (NDVI analyses were used to delineate regions of increased moisture flux and probable zones of shallow karst development. Digital Elevation Models (DEM constructed from high-resolution LiDAR (Light Detection and Ranging data were used to spatially interpret sinkholes, while analyses of LiDAR intensity data were used in a novel way to categorize local variations in surface geology. Resistivity data, including both direct current (DC and capacitively coupled (CC resistivity analyses, were acquired and interpreted throughout the study area to delineate potential shallow karst geohazards specifically associated with roadways of geohazard concern; however, detailed knowledge of the surrounding geology and local karst development proved essential for proper interpretation of resistivity inversions. The composite suite of traditional field investigations and remotely sensed karst

  19. Thin Films

    Directory of Open Access Journals (Sweden)

    M. Benmouss

    2003-01-01

    the optical absorption are consistent with the film color changes. Finally, the optical and electrochromic properties of the films prepared by this method are compared with those of our sputtered films already studied and with other works.

  20. Novel chitosan film embedded with liposome-encapsulated phage for biocontrol of Escherichia coli O157:H7 in beef.

    Science.gov (United States)

    Cui, Haiying; Yuan, Lu; Lin, Lin

    2017-12-01

    In recent years, phages used for the reduction of pathogenic bacteria have fostered many attentions, but they are liable to lost bioactivity in food due to the presence of acidic compounds, enzymes and evaporite materials. To improve the stability of phages, a chitosan edible film containing liposome-encapsulated phage was engineered in the present study. The characteristics of liposome-encapsulated phage and the chitosan film containing liposome-encapsulated phage were investigated. The encapsulation efficiency of phages in liposome reached 57.66±0.12%. Besides, the desirable physical properties of chitosan film were obtained. The chitosan film embedded with liposome-encapsulated phage exhibited high antibacterial activity against Escherichia coli O157:H7, without the impact on the sensory properties of beef. Hence, chitosan film containing liposome-encapsulated phage could be a promising antibacterial packaging for beef preservation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Gypsum scarps and asymmetric fluvial valleys in evaporitic terrains. The role of river migration, landslides, karstification and lithology (Ebro River, NE Spain)

    Science.gov (United States)

    Guerrero, J.; Gutiérrez, F.

    2017-11-01

    Most of the Spanish fluvial systems excavated in Tertiary evaporitic gypsum formations show asymmetric valleys characterized by a stepped sequence of fluvial terraces on one valley flank and kilometric-long and > 100-m high prominent river scarp on the opposite side of the valley. Scarp undermining by the continuous preferential lateral migration of the river channel toward the valley margin leads to vertical to overhanging unstable slopes affected by a large number of slope failures that become the main geological hazard for villages located at the toe of the scarps. Detailed mapping of the gypsum scarps along the Ebro and Huerva Rivers gypsum scarps demonstrates that landslides and lateral spreading processes are predominant when claystones crop out at the base of the scarp, while rockfalls and topples become the dominant movement in those reaches where the rock mass is mainly constituted by evaporites. The dissolution of gypsum nodules, seasonal swelling and shrinking, and dispersion processes contribute to a decrease in the mechanical strength of claystones. The existence of dissolution-enlarged joints, sinkholes, and severely damaged buildings at the toe of the scarp from karstic subsidence demonstrates that the interstratal karstification of evaporites becomes a triggering factor in the instability of the rock mass. The genesis of asymmetric valleys and river gypsum scarps in the study area seem to be caused by the random migration of the river channel in the absence of lateral tilting related to tectonics or dissolution-induced subsidence. Once the scarp is developed, its preservation depends on the physicochemical properties of the substratum, the ratio between bedrock erosion and river incision rates, and climatic conditions that favour runoff erosion versus dissolution.

  2. Microbial Ecosystems, Protection of

    NARCIS (Netherlands)

    Bodelier, P.L.E.; Nelson, K.E.

    2014-01-01

    Synonyms Conservation of microbial diversity and ecosystem functions provided by microbes; Preservation of microbial diversity and ecosystem functions provided by microbes Definition The use, management, and conservation of ecosystems in order to preserve microbial diversity and functioning.

  3. Microbial metropolis.

    Science.gov (United States)

    Wimpenny, Julian

    2009-01-01

    Microorganisms can form tightly knit communities such as biofilms. Many others include marine snow, anaerobic digester granules, the ginger beer plant and bacterial colonies. This chapter is devoted to a survey of the main properties of these communities, with an emphasis on biofilms. We start with attachment to surfaces and the nature of adhesion. The growing community then forms within a matrix, generally of organic macromolecules. Inevitably the environment within such a matrix is different from that outside. Organisms respond by forming crowd-detection and response units; these quorum sensing systems act as switches between planktonic life and the dramatically altered conditions found inside microbial aggregates. The community then matures and changes and may even fail and disappear. Antimicrobial resistance is discussed as an example of multicellular behavior. The multicellular lifestyle has been modeled mathematically and responded to powerful molecular biological techniques. Latterly, microbial systems have been used as models for fundamental evolutionary processes, mostly because of their high rates of reproduction and the ease of genetic manipulation. The life of most microbes is a duality between the yin of the community and the yang of planktonic existence. Sadly far less research has been devoted to adaptation to free-living forms than in the opposite direction. Copyright © 2009 Elsevier Ltd. All rights reserved.

  4. Sinkholes and caves related to evaporite dissolution in a stratigraphically and structurally complex setting, Fluvia Valley, eastern Spanish Pyrenees. Geological, geomorphological and environmental implications

    Science.gov (United States)

    Gutiérrez, Francisco; Fabregat, Ivan; Roqué, Carles; Carbonel, Domingo; Guerrero, Jesús; García-Hermoso, Fernando; Zarroca, Mario; Linares, Rogelio

    2016-08-01

    Evaporite karst and sinkhole development is analysed in a geologically complex area of NE Spain, including four evaporite units with different characteristics and affected by compressional and extensional tectonic structures. The exposed paleosinkholes, including remarkable Early Pleistocene paleontological sites, provide valuable information on the subsidence mechanisms and reveal the significant role played by interstratal karstification in the area. These gravitational deformation structures, including hectometre-scale bending folds and oversteepened normal faults, strongly suggest that the present-day compressional regime inferred in previous studies may be largely based on the analysis of non-tectonic structures. Two gypsum caves ca. 1 km long show that passages with restricted cross-sectional area may produce large breccia pipes and sinkholes thanks to the removal of breakdown boulders by high-competence episodic floods. Moreover, the upward progression of cave ceilings by paragenesis and condensation dissolution contributes to increase the probability of sinkhole occurrence. An inventory of 135 sinkholes together with their geological and geomorphological context has been developed. This data base has been used to infer several properties of the sinkholes with practical implications: a magnitude and frequency scaling relationship, spatial distribution patterns, dominant controlling factors and risk implications.

  5. The impact of droughts and climate change on sinkhole occurrence. A case study from the evaporite karst of the Fluvia Valley, NE Spain.

    Science.gov (United States)

    Linares, Rogelio; Roqué, Carles; Gutiérrez, Francisco; Zarroca, Mario; Carbonel, Domingo; Bach, Joan; Fabregat, Ivan

    2017-02-01

    This work introduces the concept that sinkhole frequency in some karst settings increases during drought periods. This conception is tested in a sector of the Fluvia River valley in NE Spain, where subsidence phenomena is related to the karstification of folded Eocene evaporite formations. In the discharge areas, the evaporites behave as confined aquifers affected by hypogene karstification caused by aggressive artesian flows coming form an underlying carbonate aquifer. A sinkhole inventory with chronological data has been constructed, revealing temporal clusters. Those clusters show a good correlation with drought periods, as revealed by precipitation, river discharge and piezometric data. This temporal association is particularly obvious for the last and current drought starting in 1998, which is the most intense of the record period (1940-present). Climatic projections based on recent studies foresee an intensification of the droughts in this sector of NE Spain, which could be accompanied by the enhancement of the sinkhole hazard and the associated risks. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Microbial mats and modern stromatolites in Shark Bay, Western Australia

    Science.gov (United States)

    Golubic, S.

    1985-01-01

    Distribution, external morphology, texture, and microbial composition of microbial mats in Hamelin Pool, Shark Bay, Western Australia, have been studied and reviewed along a composite representative profile starting from the permanently submerged zone, across the zones of periodic flooding, toward permanently emerged land and coastal dunes. The following nine types of algal mats have been recognized: colloform, gelatinous, smooth, pincushion, tufted, mamillate, film, reticulate, and blister. Solar ponds represent a particular environment. The mat types represent microbial communities that are characterized by one or more dominant microorganisms. The colonization and stabilization of loose sediment is carried out by a microbial assemblage of generalists that prepare the ground for later replacement and succession by specialized microflora. Lithification of microbial mats takes place periodically, mainly during the austral summer. This process is destructive for the microbial community but increases the preservation potential of the stromatolitic structures.

  7. Role of evaporitic sulfates in iron skarn mineralization: a fluid inclusion and sulfur isotope study from the Xishimen deposit, Handan-Xingtai district, North China Craton

    Science.gov (United States)

    Wen, Guang; Bi, Shi-Jian; Li, Jian-Wei

    2017-04-01

    The Xishimen iron skarn deposit in the Handan-Xingtai district, North China Craton, contains 256 Mt @ 43 % Fe (up to 65 %). The mineralization is dominated by massive magnetite ore along the contact zone between the early Cretaceous Xishimen diorite stock and middle Ordovician dolomite and dolomitic limestones with numerous intercalations of evaporitic beds. Minor lenticular magnetite-dominated bodies also occur in the carbonate rocks proximal to the diorite stock. Hydrothermal alteration is characterized by extensive albitization within the diorite stock and extreme development of magnesian skarn along the contact zone consisting of diopside, forsterite, serpentine, tremolite, phlogopite, and talc. Magmatic quartz and amphibole from the diorite and hydrothermal diopside from the skarns contain abundant primary or pseudosecondary fluid inclusions, most of which have multiple daughter minerals dominated by halite, sylvite, and opaque phases. Scanning electron microscopy (SEM) and laser Raman spectrometry confirm that pyrrhotite is the predominant opaque phase in most fluid inclusions, in both the magmatic and skarn minerals. These fluid inclusions have total homogenization temperatures of 416-620 °C and calculated salinities of 42.4-74.5 wt% NaCl equiv. The fluid inclusion data thus document a high-temperature, high-salinity, ferrous iron-rich, reducing fluid exsolved from a cooling magma likely represented by the Xishimen diorite stock. Pyrite from the iron ore has δ34S values ranging from 14.0 to 18.6 ‰, which are significantly higher than typical magmatic values (δ34S = 0 ± 5 ‰). The sulfur isotope data thus indicate an external source for the sulfur, most likely from the evaporitic beds in the Ordovician carbonate sequences that have δ34S values of 24 to 29 ‰. We suggest that sulfates from the evaporitic beds have played a critically important role by oxidizing ferrous iron in the magmatic-hydrothermal fluid, leading to precipitation of massive

  8. Molecular indicators for palaeoenvironmental change in a Messinian evaporitic sequence (Vena del Gesso, Italy) II. Stratigraphic changes in abundances and (13)C contents of free and sulphur-bound skeletons in a single marl bed

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Kenig, F.; Frewin, N.L.; Hayes, J.M.

    1995-01-01

    The extractable organic matter of 10 immature samples from a marl bed of one evaporitic cycle of the Vena del Gesso sediments (Gessoso-solfifera Fm., Messinian, Italy) was analyzed quantitatively for free hydrocarbons and organic sulphur compounds. Nickel boride was used as a desulphurizing agent to

  9. Nanocomposite films

    Science.gov (United States)

    Mitlin, David; , Ophus, Colin; Evoy, Stephane; Radmilovic, Velimir; Mohammadi, Reza; Westra, Ken; Nelson-Fitzpatrick, Nathaniel; Lee, Zonghoon

    2010-07-20

    A thin-film composition of nanocrystal molybdenum in an amorphous metallic matrix may be formed by co-sputtering Mo with aluminum or nickel. NEMS cantilevers may be formed from the film. The films exhibit high nanoindentation hardness and a reduction in roughness and intrinsic stress, while maintaining resistivity in the metallic range.

  10. Microbial conversions of terpenoids

    OpenAIRE

    Parshikov, Igor A

    2015-01-01

    The monograph describes examples of the application of microbial technology for obtaining of derivatives of terpenoids. Obtaining new derivatives of terpenoids, including artemisinin derivatives with increased antimalarial activity, is an important goal of research in microbial biotechnology and medicinal chemistry.

  11. The microbial community at Laguna Figueroa, Baja California Mexico - From miles to microns

    Science.gov (United States)

    Stolz, J. F.

    1985-01-01

    The changes in the composition of the stratified microbial community in the sediments at Laguna Figeroa following floods are studied. The laguna which is located on the Pacific coast of the Baja California peninsula 200 km south of the Mexican-U.S. border is comprised of an evaporite flat and a salt marsh. Data collected from 1979-1983 using Landsat imagery, Skylab photographs, and light and transmission electron microscopy are presented. The flood conditions, which included 1-3 m of meteoric water covering the area and a remanent of 5-10 cm of siliciclastic and clay sediment, are described. The composition of the community prior to the flooding consisted of Microcoleus, Phormidium sp., a coccoid cynanobacteria, Phloroflexus, Ectothiorhodospira, Chloroflexus, Thiocapsa sp., and Chromatium. Following the floods Thiocapsa, Chromatium, Oscillatora sp., Spirulina sp., and Microcoleus are observed in the sediments.

  12. Molecular microbial ecology manual

    NARCIS (Netherlands)

    Kowalchuk, G.A.; Bruijn, de F.J.; Head, I.M.; Akkermans, A.D.L.

    2004-01-01

    The field of microbial ecology has been revolutionized in the past two decades by the introduction of molecular methods into the toolbox of the microbial ecologist. This molecular arsenal has helped to unveil the enormity of microbial diversity across the breadth of the earth's ecosystems, and has

  13. Identification and applicability of analogues for a safety case for a HLW repository in evaporites: results from a NEA workshop

    Energy Technology Data Exchange (ETDEWEB)

    Noseck, U.; Wolf, J. [Gesellschaft für Anlagen und Reaktorsicherheit (GRS) mbH, Brunswick (Germany); Steininger, W. [Project Management Agency Karslruhe Water Technology and Waste Management, PTKA-WTE, Karlsruhe Institute of Technology, KIT, Eggenstein-Leopoldshafen (Germany); Miller, B. [AMEC, The Renaissance Center, Warrington (United Kingdom)

    2015-06-15

    A workshop was held in September 2012 in Braunschweig, Germany, to discuss the potential for natural and anthropogenic analogue studies to contribute to safety cases for radioactive waste repositories constructed in salt formations. Presentations were given on many analogue sites and systems from different countries. Discussions at the workshop then addressed the following aspects that are particularly relevant to the safety concept for radioactive waste disposal in salt: (1) the long-term integrity of rock salt formations, (2) the integrity of technical barriers, and (3) microbial, chemical and transport processes. A diverse range of natural systems were discussed as potential analogues for the integrity of rock salt. These included the deformation of anhydrite layers in rock salt; the response of rock salt to mechanical and thermal loads; and the isotopic signatures of syngenetic waters contained in fluid inclusions. Some anthropogenic examples drawn from the oil and gas industries, and from hazardous waste disposal, were proposed as analogues for the integrity of (geo)technical barriers. A broad range of studies on natural and anthropogenic salt-brine systems were identified as potential analogues for the radionuclide sorption and (co)precipitation process that may take place in the repository near and far fields, as well as for understanding the significance of hydrocarbons and microbial processes. It was evident from discussions at the workshop that there are some specific technical issues that may benefit from further analogue study, particularly the compaction of crushed salt backfill, the viability of microbes in the near-field, the stability of plugs and seals, the deformation of anhydrite, and isotope signatures in fluid inclusions. (authors)

  14. Demens Film

    DEFF Research Database (Denmark)

    Jensen, Anders Møller

    2012-01-01

    Vi vil skabe film til mennesker med demens – ikke film om demens sygdommen eller beretninger om livet og hverdagen med en kronisk lidelse. Filmene skal medvirke til at frembringe en behagelig stemning omkring og hos mennesker med demens, så hverdagen bliver så tryg som mulig. Filmene skal samtidig...... var at afgrænse og prioritere projektet, samt komme med anbefalinger omkring hvad der er vigtigt, i forbindelse med produktion af film målrettet mennesker med demens. Resultat af ekspertgruppen sammenfattes i denne rapport. Projektet gennemføres som et samarbejde mellem Retrospect Film...

  15. [Microbial biosensors for detection of biological oxygen demand (a review)].

    Science.gov (United States)

    Ponamoreva, O N; Arliapov, V A; Alferov, V A; Reshetilov, A N

    2011-01-01

    The review briefs recent advances in application of biosensors for determining biological oxygen demand (BOD) in water. Special attention is focused on the principles of operation of microbial BOD sensors; the information about biorecognition elements in such systems and the methods used for immobilization of biological components in film biosensors is summarized. Characteristics of some BOD sensor models are considered in detail.

  16. Thin Film

    African Journals Online (AJOL)

    a

    TiO2 film and also the photo generated electrons are the charge carriers. As anodic potential increased, a large amount of current carrier (photoelectrons) passed through the TiO2 film. Additionally, photogenerated holes were consumed by methyl orange in the solution, which is reflected in the decrease of absorbance. 0.

  17. A Little Vacation on Mars: Mars Simulation Microbial Challenge Experiments

    Science.gov (United States)

    Boston, P.; Todd, P.; Van De Camp, J.; Northup, D.; Spilde, M.

    2008-06-01

    Communities of microbial organisms isolated from a variety of extreme environments were subjected to 1 to 5 weeks of simulated Martian environmental conditions using the Mars Environment Simulation Chamber at the Techshot, Inc. facility in Greenville, Indiana. The goal of the overall experiment program was to assess survival of test Earth organisms under Mars full spectrum sunlight, low-latitude daily temperature profile and various Mars-atmosphere pressures (~50 mbar to 500 mbar, 100% CO2) and low moisture content. Organisms surviving after 5 weeks at 100 mbar included those from gypsum surface fracture communities in a Permian aged evaporite basin, desert varnish on andesite lavas around a manganese mine, and iron and manganese oxidizing organisms isolated from two caves in Mew Mexico. Phylogenetic DNA analysis revealed strains of cyanobacteria, bacterial genera (present in all surviving communities) Asticacaulis, Achromobacter, Comamonas, Pantoea, Verrucomicrobium, Bacillus, Gemmatimonas, Actinomyces, and others. At least one microcolonial fungal strain from a desert varnish community and at least one strain from Utah survived simulations. Strains related to the unusual cave bacterial group Bacteroidetes are present in survivor communities that resist isolation into pure culture implying that their consortial relationships may be critical to their survival.

  18. Microbial electrosynthetic cells

    Energy Technology Data Exchange (ETDEWEB)

    May, Harold D.; Marshall, Christopher W.; Labelle, Edward V.

    2018-01-30

    Methods are provided for microbial electrosynthesis of H.sub.2 and organic compounds such as methane and acetate. Method of producing mature electrosynthetic microbial populations by continuous culture is also provided. Microbial populations produced in accordance with the embodiments as shown to efficiently synthesize H.sub.2, methane and acetate in the presence of CO.sub.2 and a voltage potential. The production of biodegradable and renewable plastics from electricity and carbon dioxide is also disclosed.

  19. Demens Film

    DEFF Research Database (Denmark)

    Ridder, Hanne Mette Ochsner

    2012-01-01

    I forbindelse med opstarten af Demens Film projektet har der været nedsat en ekspertgruppe, som er kommet med en række anbefalinger omkring film til mennesker med demens. Anbefalingerne skal bruges i de næste faser af projektet. Deltagerne i ekspertgruppen var sammensat af en bred gruppe...... fagpersoner inde for forskellige fagområder. Læs mere om gruppens anbefalinger og sammensætning af ekspertgruppen i den kort rapport som er offentlig tilgængelig. Læs Ekspertgruppe anbefalingerne til Demens Film projekt....

  20. Microbially induced sedimentary structures in evaporite–siliciclastic sediments of Ras Gemsa sabkha, Red Sea Coast, Egypt

    Directory of Open Access Journals (Sweden)

    Amany G. Taher

    2014-09-01

    Full Text Available The coastal sabkha in Ras Gemsa, Red Sea coast with its colonizing microbial mats and biofilms was investigated. The sabkha sediments consist mainly of terrigenous siliciclastic material accompanied by the development of evaporites. Halite serves as a good conduit for light and reduces the effect of intensive harmful solar radiation, which allows microbial mats to survive and flourish. The microbial mats in the evaporite–siliciclastic environments of such sabkha display distinctive sedimentary structures (microbially induced sedimentary structures, including frozen multidirected ripple marks, salt-encrusted crinkle mats, jelly roll structure, and petee structures. Scanning electron microscopy of the sediment surface colonized by cyanobacteria revealed that sand grains of the studied samples are incorporated into the biofilm by trapping and binding processes. Filamentous cyanobacteria and their EPS found in the voids in and between the particles construct a network that effectively interweaves and stabilizes the surface sediments. In advanced stages, the whole surface is covered by a spider web-like structure of biofilm, leading to a planar surface morphology. Sabkha with its chemical precipitates is a good model for potential preservation of life signatures. It is worthy to note that the available, published works on the subject of the present work are not numerous.

  1. Linking Archaeal Molecular Diversity and Lipid Biomarker Composition in a Hypersaline Microbial Mat Community

    Science.gov (United States)

    Jahnke, Linda; Orphan, Victoria; Turk, Kendra; Embaye, Tsegereda; Kubo, Mike; Summons, Roger

    2005-01-01

    Lipid biomarkers for discrete microbial groups are a valuable tool for establishing links to ancient microbial ecosystems. Lipid biomarkers can establish organism source and function in contemporary microbial ecosystems (membrane lipids) and by analogy, potential relevance to the fossilized carbon skeletons (geolipids) extracted from ancient sedimentary rock. The Mars Exploration Rovers have provided clear evidence for an early wet Mars and the presence of hypersaline evaporitic basins. Ongoing work on an early Earth analog, the hypersaline benthic mats in Guerrero Negro, Baja California Sur, may provide clues to what may have evolved and flourished on an early wet Mars, if only for a short period. Cyanobacterial mats are a pertinent early Earth analog for consideration of evolutionary and microbial processes within the aerobic photosynthetic and adjacent anoxic layers. Fluctuations in physio-chemical parameters associated with spatial and temporal scales are expressed through vast microbial metabolic diversity. Our recent work hopes to establish the dynamic of archaeal diversity, particularly as it relates to methane production in this high sulfate environment, through the use of lipid biomarker and phylogenetic analyses. Archaeal 16s rRNA and mcrA gene assemblages, demonstrated distinct spatial separation over the 130 mm core of at least three distinct genera within the order Methanosarcinales, as well as an abundance of uncultured members of the Thermoplasmales and Crenarchaeota. Ether-bound lipid analysis identified abundant 0-alkyl and 0-isopranyl chains throughout the core, and the presence of sn-2 hydroxyarchaeol, a biomarker for methylotrophic methanogens. A unique ether isoprenoid chain, a C30:1 , possibly related to the geolipid squalane, a paleobiomarker associated with hypersaline environments, was most abundant within the oxic-anoxic transition zone.

  2. Microbial Enzymatic Degradation of Biodegradable Plastics.

    Science.gov (United States)

    Roohi; Bano, Kulsoom; Kuddus, Mohammed; Zaheer, Mohammed R; Zia, Qamar; Khan, Mohammed F; Ashraf, Ghulam Md; Gupta, Anamika; Aliev, Gjumrakch

    2017-01-01

    The renewable feedstock derived biodegradable plastics are important in various industries such as packaging, agricultural, paper coating, garbage bags and biomedical implants. The increasing water and waste pollution due to the available decomposition methods of plastic degradation have led to the emergence of biodegradable plastics and biological degradation with microbial (bacteria and fungi) extracellular enzymes. The microbes utilize biodegradable polymers as the substrate under starvation and in unavailability of microbial nutrients. Microbial enzymatic degradation is suitable from bioremediation point of view as no waste accumulation occurs. It is important to understand the microbial interaction and mechanism involved in the enzymatic degradation of biodegradable plastics under the influence of several environmental factors such as applied pH, thermo-stability, substrate molecular weight and/or complexity. To study the surface erosion of polymer film is another approach for hydrolytic degradation characteristion. The degradation of biopolymer is associated with the production of low molecular weight monomer and generation of carbon dioxide, methane and water molecule. This review reported the degradation study of various existing biodegradable plastics along with the potent degrading microbes (bacteria and fungi). Patents available on plastic biodegradation with biotechnological significance is also summarized in this paper. This paper assesses that new disposal technique should be adopted for the degradation of polymers and further research is required for the economical production of biodegradable plastics along with their enzymatic degradation. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  3. Film Reviews

    Science.gov (United States)

    Ladd, George T.

    1974-01-01

    Briefly describes films about the following topics: water cycles, the energy crisis, the eruption of Mt. Aetna, the hot springs of Yellowstone National Park, and methods of using pine cones to determine the ages of ancient civilizations. (MLH)

  4. Piezoelectric Film.

    Science.gov (United States)

    Garrison, Steve

    1992-01-01

    Presents activities that utilize piezoelectric film to familiarize students with fundamental principles of electricity. Describes classroom projects involving chemical sensors, microbalances, microphones, switches, infrared sensors, and power generation. (MDH)

  5. Polymer films

    Science.gov (United States)

    Granick, Steve; Sukhishvili, Svetlana A.

    2004-05-25

    A film contains a first polymer having a plurality of hydrogen bond donating moieties, and a second polymer having a plurality of hydrogen bond accepting moieties. The second polymer is hydrogen bonded to the first polymer.

  6. MICROBIAL FUEL CELL

    DEFF Research Database (Denmark)

    2008-01-01

    A novel microbial fuel cell construction for the generation of electrical energy. The microbial fuel cell comprises: (i) an anode electrode, (ii) a cathode chamber, said cathode chamber comprising an in let through which an influent enters the cathode chamber, an outlet through which an effluent...

  7. thin films

    Indian Academy of Sciences (India)

    by successive ionic layer adsorption and reaction (SILAR) method at room temperature (∼300 K). The films are characterized for their ... two steps: (i) adsorption of Sn4+ ions on the substrate surface for 20 s and (ii) reaction with ... The mechanism of formation of SnO2:H2O film can be eluci- dated as follows. The SnCl2 ...

  8. Messinian post-evaporitic paleogeography of the Po Plain-Adriatic region by 3D numerical modeling: implications for the Central Mediterranean desiccation during the MSC

    Science.gov (United States)

    Amadori, Chiara; Garcia-Castellanos, Daniel; Di Giulio, Andrea; Fantoni, Roberto; Ghielmi, Manlio; Sternai, Pietro; Toscani, Giovanni

    2017-04-01

    In the last decades the Messinian Salinity Crisis (MSC) has been the topic of a number of studies, in particular in onshore areas, as they offer a unique opportunity to analyze the controlling factors and the geological consequences of the estimated 1.5 km sea-level drop. During the MSC, the geometry of western and eastern sides of the Mediterranean basin was similar to the present day basin while, important changes took place in the central portion as a consequence of the (still ongoing) tectonic activity of the Apennine domain. Recent high-resolution 2D seismo-stratigraphic and 1D backstripping analysis by Eni E&P group described a step-wise sea-level lowering during evaporitic and post-evaporitic MSC phases in the Po Plain-Northern Adriatic foreland (PPAF), with a sea-level drop not exceeding 900 m. Thanks to a dense grid of 2D seismic profiles, integrated with ca. 200 well logs (confidential data, courtesy of ENI E&P), a 3D reconstruction of the entire northern PPAF basin geometry and the facies distribution during the Latest Messinian time has been carried out. In this study, we performed a 3D backstripping and lithospheric scale uplift calculations of the northern PPAF basin testing the 800-900m of sea-level draw down. The resulted restored Latest Messinian paleotopography (corresponding to the bottom Pliocene in the most of the study area) and related shoreline position, strongly fit with the recentmost continental/marine facies distribution maps. The latest Messinian morphology shows deep marine basins persisting during the entire MSC period, filled by clastic turbiditic sediments and a wide emerged area along the Southern Alps margin and Friulian-Venetian basin. A 3D reconstruction of the Latest Messinian surface shows peculiar river incisions along the Southern Alps margin; these V-shape canyons perfectly fit with the present day fluvial network, dating back the drainage origin at least at the Messinian acme. Moreover, if in a well-constrained marginal

  9. Conditions for the formation and atmospheric dispersion of a toxic, heavy gas layer during thermal metamorphism of coal and evaporite deposits by sill intrusion

    Science.gov (United States)

    Storey, Michael; Hankin, Robin K. S.

    2010-05-01

    There is compelling evidence for massive discharge of volatiles, including toxic species, into the atmosphere at the end of the Permian. It has been argued that most of the gases were produced during thermal metamorphism of coal and evaporite deposits in the East Siberia Tunguska basin following sill intrusion (Retallack and Jahren, 2008; Svensen et al., 2009). The release of the volatiles has been proposed as a major cause of environmental and extinction events at the end of the Permian, with venting of carbon gases and halocarbons to the atmosphere leading to global warming and atmospheric ozone depletion (Svensen et al., 2009) Here we consider the conditions required for the formation and dispersion of toxic, heavier than air, gas plumes, made up of a mixture of CO2, CH4, H2S and SO2 and formed during the thermal metamorphism of C- and S- rich sediments. Dispersion models and density considerations within a range of CO2/CH4 ratios and volatile fluxes and temperatures, for gas discharge by both seepage and from vents, allow the possibility that following sill emplacement much of the vast East Siberia Tunguska basin was - at least intermittently - covered by a heavy, toxic gas layer that was unfavorable for life. Dispersion scenarios for a heavy gas layer beyond the Siberian region during end-Permian times will be presented. REFERENCES G. J. Retallack and A. H. Jahren, Methane release from igneous intrusion of coal during Late Permian extinction events, Journal of Geology, volume 116, 1-20, 2008 H. Svensen et al., Siberian gas venting and the end-Permian environmental crisis, Earth and Planetary Science Letters, volume 277, 490-500, 2009

  10. Science Fiction on Film.

    Science.gov (United States)

    Burmester, David

    1985-01-01

    Reviews science fiction films used in a science fiction class. Discusses feature films, short science fiction films, short story adaptations, original science fiction pieces and factual science films that enrich literature. (EL)

  11. Safety Assessment of Microbial Polysaccharide Gums as Used in Cosmetics.

    Science.gov (United States)

    Fiume, Monice M; Heldreth, Bart; Bergfeld, Wilma F; Belsito, Donald V; Hill, Ronald A; Klaassen, Curtis D; Liebler, Daniel C; Marks, James G; Shank, Ronald C; Slaga, Thomas J; Snyder, Paul W; Andersen, F Alan

    2016-07-01

    The Cosmetic Ingredient Review Expert Panel assessed the safety of 34 microbial polysaccharide gums for use in cosmetics, finding that these ingredients are safe in cosmetic formulations in the present practices of use and concentration. The microbial polysaccharide gums named in this report have a variety of reported functions in cosmetics, including emulsion stabilizer, film former, binder, viscosity-increasing agent, and skin-conditioning agent. The Panel reviewed available animal and clinical data in making its determination of safety. © The Author(s) 2016.

  12. Microbial characteristics of biogas.

    Science.gov (United States)

    Moletta, Marina; Wery, Nathalie; Delgenes, Jean-Philippe; Godon, Jean-Jacques

    2008-01-01

    The microbial diversity of biogas was analyzed in order to examine the aerosolization behavior of microorganisms. Six biogas samples were analyzed: five from mesophilic and thermophilic anaerobic digestors treating different wastes, and one from landfill. Epifluorescent microscopic counts revealed 10(6) prokarya m(-3). To assess the difference occuring in aerosolization, 498 biogas-borne 16S ribosomal DNA were analyzed and compared to published anaerobic digestor microbial diversity. Results show a large microbial diversity and strong discrepancy with digestor microbial diversity. Three different aerosolisation behaviour patterns can be identified: (i) that of non-aerosolized microorganisms, Deltaproteobacteria, Spirochaetes, Thermotogae, Chloroflexi phyla and sulfate-reducing groups, (ii) that of passively aerosolized microorganisms, including Actinobacteria, Firmicutes and Bacteroidetes phyla and (iii) that of preferentially aerosolized microorganisms, including Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, as well as strictly aerobic and occasionally pathogenic species, presented high levels of aerosolization.

  13. Molecular and lipid biomarker analysis of a gypsum-hosted endoevaporitic microbial community.

    Science.gov (United States)

    Jahnke, L L; Turk-Kubo, K A; N Parenteau, M; Green, S J; Kubo, M D Y; Vogel, M; Summons, R E; Des Marais, D J

    2014-01-01

    Modern evaporitic microbial ecosystems are important analogs for understanding the record of earliest life on Earth. Although mineral-depositing shallow-marine environments were prevalent during the Precambrian, few such environments are now available today for study. We investigated the molecular and lipid biomarker composition of an endoevaporitic gypsarenite microbial mat community in Guerrero Negro, Mexico. The 16S ribosomal RNA gene-based phylogenetic analyses of this mat corroborate prior observations indicating that characteristic layered microbial communities colonize gypsum deposits world-wide despite considerable textural and morphological variability. Membrane fatty acid analysis of the surface tan/orange and lower green mat crust layers indicated cell densities of 1.6 × 10(9) and 4.2 × 10(9)  cells cm(-3) , respectively. Several biomarker fatty acids, ∆7,10-hexadecadienoic, iso-heptadecenoic, 10-methylhexadecanoic, and a ∆12-methyloctadecenoic, correlated well with distributions of Euhalothece, Stenotrophomonas, Desulfohalobium, and Rhodobacterales, respectively, revealed by the phylogenetic analyses. Chlorophyll (Chl) a and cyanobacterial phylotypes were present at all depths in the mat. Bacteriochlorophyl (Bchl) a and Bchl c were first detected in the oxic-anoxic transition zone and increased with depth. A series of monomethylalkanes (MMA), 8-methylhexadecane, 8-methylheptadecane, and 9-methyloctadecane were present in the surface crust but increased in abundance in the lower anoxic layers. The MMA structures are similar to those identified previously in cultures of the marine Chloroflexus-like organism 'Candidatus Chlorothrix halophila' gen. nov., sp. nov., and may represent the Bchl c community. Novel 3-methylhopanoids were identified in cultures of marine purple non-sulfur bacteria and serve as a probable biomarker for this group in the lower anoxic purple and olive-black layers. Together microbial culture and environmental analyses

  14. Microbial bioinformatics 2020.

    Science.gov (United States)

    Pallen, Mark J

    2016-09-01

    Microbial bioinformatics in 2020 will remain a vibrant, creative discipline, adding value to the ever-growing flood of new sequence data, while embracing novel technologies and fresh approaches. Databases and search strategies will struggle to cope and manual curation will not be sustainable during the scale-up to the million-microbial-genome era. Microbial taxonomy will have to adapt to a situation in which most microorganisms are discovered and characterised through the analysis of sequences. Genome sequencing will become a routine approach in clinical and research laboratories, with fresh demands for interpretable user-friendly outputs. The "internet of things" will penetrate healthcare systems, so that even a piece of hospital plumbing might have its own IP address that can be integrated with pathogen genome sequences. Microbiome mania will continue, but the tide will turn from molecular barcoding towards metagenomics. Crowd-sourced analyses will collide with cloud computing, but eternal vigilance will be the price of preventing the misinterpretation and overselling of microbial sequence data. Output from hand-held sequencers will be analysed on mobile devices. Open-source training materials will address the need for the development of a skilled labour force. As we boldly go into the third decade of the twenty-first century, microbial sequence space will remain the final frontier! © 2016 The Author. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  15. New applications of carbon nanostructures in microbial fuel cells (MFC)

    Science.gov (United States)

    Kaca, W.; Żarnowiec, P.; Keczkowska, Justyna; Suchańska, M.; Czerwosz, E.; Kozłowski, M.

    2014-11-01

    In the studies presented we proposed a new application for nanocomposite carbon films (C-Pd). These films were evaluated as an anode material for Microbial Fuel Cells (MFCs) used for electrical current generation. The results of characterization of C-Pd films composed of carbon and palladium nanograins were obtained using the Physical Vapor Deposition (PVD) method. The film obtained by this method exhibits a multiphase structure composed of fullerene nanograins, amorphous carbon and palladium nanocrystals. Raman Spectroscopy (RS) and scanning electron microscopy (SEM) are used to characterize the chemical composition, morphology and topography of these films. We observed, for MFC with C-Pd anode, the highest electrochemical activity and maximal voltage density - 458 mV (20,8 mV/cm2) for Proteus mirabilis, 426 mV (19,4 mV/cm2) for Pseudomonas aeruginosa and 652 mV (29,6 mV/cm2) for sewage bacteria as the microbial catalyst.

  16. Microbial life in ice and subglacial environments

    Science.gov (United States)

    Price, P. B.; Bramall, N.; Tatebe, K.

    2003-04-01

    Conditions for microbial life to exist in solid ice require the presence of liquid water and sources of energy and bioelements. In ice in thermal equilibrium, liquid water will exist in a three-dimensional network of micron-sized veins and in nanometer-thick films on mineral grains in ice. Ionic impurities lower the freezing temperature in the veins to as low as -95^oC. Depending on mineral type, the film on a grain surface will remain liquid down to ˜ -40^oC. The impurities provide both energy (via microbially catalyzed redox reactions) and bioelements. The maximum sustainable microbial population depends on metabolic rate, which in turn depends on species, temperature, and type and concentration of impurities in veins and surfaces. Microbes have been imaged by epifluorescence in veins in sea and Arctic lake ice and on grains in Dry Valleys lake ice. Indirect evidence exists for metabolism of microbes in Vostok glacial ice, in Greenland basal ice, and in Sajama (Bolivia) glacial ice. We will discuss several approaches to detection of microbes: epifluorescence microscopy of glacial ice at low temperature; fluorescence spectra taken with BSL (a new borehole logging instrument); fluorescence of microbes on surfaces of silt and volcanic ash in glacial ice; and in-situ cultivation of bacterial colonies at intersections of mineral grains and liquid veins in ice held in contact with a nutrient medium at subfreezing temperature. Based on measurements in the oligotrophic Lake Tahoe, BSL is sensitive to a concentration of ˜10^3 microbes cm-3, which may be adequate to detect life in Greenland ice and in Lake Vostok. A miniaturized version could be used to search for life in Martian permafrost and in diapirs in Europan ice.

  17. The Microbial Olympics

    Science.gov (United States)

    Youle, Merry; Rohwer, Forest; Stacy, Apollo; Whiteley, Marvin; Steel, Bradley C.; Delalez, Nicolas J.; Nord, Ashley L.; Berry, Richard M.; Armitage, Judith P.; Kamoun, Sophien; Hogenhout, Saskia; Diggle, Stephen P.; Gurney, James; Pollitt, Eric J. G.; Boetius, Antje; Cary, S. Craig

    2014-01-01

    Every four years, the Olympic Games plays host to competitors who have built on their natural talent by training for many years to become the best in their chosen discipline. Similar spirit and endeavour can be found throughout the microbial world, in which every day is a competition to survive and thrive. Microorganisms are trained through evolution to become the fittest and the best adapted to a particular environmental niche or lifestyle, and to innovate when the ‘rules of the game’ are changed by alterations to their natural habitats. In this Essay, we honour the best competitors in the microbial world by inviting them to take part in the inaugural Microbial Olympics. PMID:22796885

  18. Graphene-Based Flexible Micrometer-Sized Microbial Fuel Cell

    KAUST Repository

    Mink, Justine E.

    2013-10-23

    Microbial fuel cells harvest electrical energy produced by bacteria during the natural decomposition of organic matter. We report a micrometer-sized microbial fuel cell that is able to generate nanowatt-scale power from microliters of liquids. The sustainable design is comprised of a graphene anode, an air cathode, and a polymer-based substrate platform for flexibility. The graphene layer was grown on a nickel thin film by using chemical vapor deposition at atmospheric pressure. Our demonstration provides a low-cost option to generate useful power for lab-on-chip applications and could be promising to rapidly screen and scale up microbial fuel cells for water purification without consuming excessive power (unlike other water treatment technologies).

  19. Chlorophyll and carotenoid pigments in solar saltern microbial mats

    Science.gov (United States)

    Villanueva, Joan; Grimalt, Joan O.; de Wit, Rutger; Keely, Brendan J.; Maxwell, James R.

    1994-11-01

    The distributions of carotenoids, chlorophylls, and their degradation products have been studied in two microbial mat systems developed in the calcite and calcite/gypsum evaporite domains of a solar saltern system. Phormidium valderianum and Microcoleus chthonoplastes are the dominant cyanobacterial species, respectively, and large amounts of Chloroflexus-like bacteria occur in the carbonate/gypsum mat. In both systems, the major pigments are chlorophyll a, zeaxanthin, β-carotene and myxoxanthophyll, which originate from these mat-building cyanobacteria. This common feature contrasts with differences in other pigments that are specific for each mat community. Thus, chlorophyll c and fucoxanthin, reflecting diatom inputs, are only found in the calcite mat, whereas the calcite/gypsum mat contains high concentrations of bacteriochlorophylls c produced by the multicellular green filamentous bacteria. In both cases, the depth concentration profiles (0-30 and 0-40 mm) show a relatively good preservation of the cyanobacterial carotenoids, zeaxanthin, β-carotene, myxoxanthophyll, and echinenone. This contrasts with the extensive biodegradation of cyanobacterial remains observed microscopically. Fucoxanthin in the calcite mat is also transformed at a faster rate than the cyanobacterial carotenoids. Chlorophyll a, the major pigment in both mats, exhibits different transformation pathways. In the calcite/gypsum mat, it is transformed via C-13 2 carbomethoxy defunctionalization prior to loss of the phytyl chain, leading to the formation of pyrophaeophytin a and, subsequently, pyrophaeophorbide a. On the other hand, the occurrence of the enzyme chlorophyllase, attributed to diatoms in the calcite mat, gives rise to extensive phytyl hydrolysis, with the formation of chlorophyllide a, pyrophaeophorbide a and, in minor proportion, phaeophorbide a. Studies of the sources of the photosynthetic pigments and of their transformation pathways in such simplified ecosystems provide a

  20. Film: An Introduction.

    Science.gov (United States)

    Fell, John L.

    "Understanding Film," the opening section of this book, discusses perceptions of and responses to film and the way in which experiences with and knowledge of other media affect film viewing. The second section, "Film Elements," analyzes the basic elements of film: the use of space and time, the impact of editing, sound and color, and the effects…

  1. Charge transport in films of Geobacter sulfurreducens on graphite electrodes as a function of film thickness

    KAUST Repository

    Jana, Partha Sarathi

    2014-01-01

    Harnessing, and understanding the mechanisms of growth and activity of, biofilms of electroactive bacteria (EAB) on solid electrodes is of increasing interest, for application to microbial fuel and electrolysis cells. Microbial electrochemical cell technology can be used to generate electricity, or higher value chemicals, from organic waste. The capability of biofilms of electroactive bacteria to transfer electrons to solid anodes is a key feature of this emerging technology, yet the electron transfer mechanism is not fully characterized as yet. Acetate oxidation current generated from biofilms of an EAB, Geobacter sulfurreducens, on graphite electrodes as a function of time does not correlate with film thickness. Values of film thickness, and the number and local concentration of electrically connected redox sites within Geobacter sulfurreducens biofilms as well as a charge transport diffusion co-efficient for the biofilm can be estimated from non-turnover voltammetry. The thicker biofilms, of 50 ± 9 μm, display higher charge transport diffusion co-efficient than that in thinner films, as increased film porosity of these films improves ion transport, required to maintain electro-neutrality upon electrolysis. This journal is © the Partner Organisations 2014.

  2. 11 Soil Microbial Biomass

    African Journals Online (AJOL)

    A field experiment to monitor the dynamics of microbial biomass carbon, nitrogen and phosphorus under amendments and cropping ... Biomass carbon showed positive correlations with soil organic carbon with r values of 0.71, 0.40 and 0.64 in 2006 (major) .... (Jenkinson, 1988; Ross & Tate, 1993) were used, respectively.

  3. Microbial Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, Merry [American Society for Microbiology (ASM), Washington, DC (United States); Wall, Judy D. [Univ. of Missouri, Columbia, MO (United States)

    2006-10-01

    The American Academy of Microbiology convened a colloquium March 10-12, 2006, in San Francisco, California, to discuss the production of energy fuels by microbial conversions. The status of research into various microbial energy technologies, the advantages and disadvantages of each of these approaches, research needs in the field, and education and training issues were examined, with the goal of identifying routes for producing biofuels that would both decrease the need for fossil fuels and reduce greenhouse gas emissions. Currently, the choices for providing energy are limited. Policy makers and the research community must begin to pursue a broader array of potential energy technologies. A diverse energy portfolio that includes an assortment of microbial energy choices will allow communities and consumers to select the best energy solution for their own particular needs. Funding agencies and governments alike need to prepare for future energy needs by investing both in the microbial energy technologies that work today and in the untested technologies that will serve the world’s needs tomorrow. More mature bioprocesses, such as ethanol production from starchy materials and methane from waste digestors, will find applications in the short term. However, innovative techniques for liquid fuel or biohydrogen production are among the longer term possibilities that should also be vigorously explored, starting now. Microorganisms can help meet human energy needs in any of a number of ways. In their most obvious role in energy conversion, microorganisms can generate fuels, including ethanol, hydrogen, methane, lipids, and butanol, which can be burned to produce energy. Alternatively, bacteria can be put to use in microbial fuel cells, where they carry out the direct conversion of biomass into electricity. Microorganisms may also be used some day to make oil and natural gas technologies more efficient by sequestering carbon or by assisting in the recovery of oil and

  4. Microbial transport systems

    National Research Council Canada - National Science Library

    Winkelmann, Günther

    2001-01-01

    ... transport is the plasma membrane, which may be accompanied by an outer membrane in the case of gram-negative bacteria. Due to their long evolutionary development, microbial cells are the most diverse with respect to transport. The various mechanisms of solute transport across these membranes are so diverse that it is surprising that cells can manage...

  5. Microbial solubilization of coal

    Science.gov (United States)

    Strandberg, G.W.; Lewis, S.N.

    1988-01-21

    The present invention relates to a cell-free preparation and process for the microbial solubilization of coal into solubilized coal products. More specifically, the present invention relates to bacterial solubilization of coal into solubilized coal products and a cell-free bacterial byproduct useful for solubilizing coal. 5 tabs.

  6. SEAGRASS RHIZOSPHERE MICROBIAL COMMUNITIES

    Science.gov (United States)

    Devereux, Richard. 2005. Seagrass Rhizosphere Microbial Communities. In: Interactions Between Macro- and Microorganisms in Marine Sediments. E. Kristense, J.E. Kostka and R.H. Haese, Editors. American Geophysical Union, Washington, DC. p199-216. (ERL,GB 1213). Seagrasses ...

  7. Ferroelectric ultrathin perovskite films

    Science.gov (United States)

    Rappe, Andrew M; Kolpak, Alexie Michelle

    2013-12-10

    Disclosed herein are perovskite ferroelectric thin-film. Also disclosed are methods of controlling the properties of ferroelectric thin films. These films can be used in a variety materials and devices, such as catalysts and storage media, respectively.

  8. Film Noir Style Genealogy

    OpenAIRE

    Dita Rietuma

    2012-01-01

    Annotation for the Doctoral Work Film Noir Style Genealogy (The Genealogy of the Film Noir Style) The doctoral work topic Film Noir Style Genealogy encompasses traditionally approved world film theory views on the concept of film noir and its related cinematographic heritage, and an exploration of its evolution and distinctive style, including – the development of film noir in the USA, Europe, and also in Latvia, within the context of both socio-political progression and the paradigm of m...

  9. Thraustochytrid protists as a component of marine microbial films

    Digital Repository Service at National Institute of Oceanography (India)

    Raghukumar, S.; Anil, A.C.; Khandeparker, L.; Patil, J.S.

    that cells of the thraustochytrid attached directly to the surfaces, without producing copious extracellular polysaccharides. The presence of ectoplasmic net elements was not a prerequisite for attachment of cells to surfaces. Cell surface hydrophobicity...

  10. Global Microbial Identifier

    DEFF Research Database (Denmark)

    Wielinga, Peter; Hendriksen, Rene S.; Aarestrup, Frank Møller

    2017-01-01

    Human and animal populations are increasingly confronted with emerging and re-emerging infections and often such infections are exchanged between these populations, e.g. through food. A more effective and uniform approach to the prevention of these microbial threats is essential. The technological......-source systems. There is therefore an obvious need to develop a global system of whole microbial genome databases to aggregate, share, mine and use microbiological genomic data, to address global public health and clinical challenges, and most importantly to identify and diagnose infectious diseases. The global...... of microorganisms, for the identification of relevant genes and for the comparison of genomes to detect outbreaks and emerging pathogens. To harness the full potential of WGS, a shared global database of genomes linked to relevant metadata and the necessary software tools needs to be generated, hence the global...

  11. Microbial Risk Assessment

    Science.gov (United States)

    Ott, C. M.; Mena, K. D.; Nickerson, C.A.; Pierson, D. L.

    2009-01-01

    Historically, microbiological spaceflight requirements have been established in a subjective manner based upon expert opinion of both environmental and clinical monitoring results and the incidence of disease. The limited amount of data, especially from long-duration missions, has created very conservative requirements based primarily on the concentration of microorganisms. Periodic reevaluations of new data from later missions have allowed some relaxation of these stringent requirements. However, the requirements remain very conservative and subjective in nature, and the risk of crew illness due to infectious microorganisms is not well defined. The use of modeling techniques for microbial risk has been applied in the food and potable water industries and has exceptional potential for spaceflight applications. From a productivity standpoint, this type of modeling can (1) decrease unnecessary costs and resource usage and (2) prevent inadequate or inappropriate data for health assessment. In addition, a quantitative model has several advantages for risk management and communication. By identifying the variable components of the model and the knowledge associated with each component, this type of modeling can: (1) Systematically identify and close knowledge gaps, (2) Systematically identify acceptable and unacceptable risks, (3) Improve communication with stakeholders as to the reasons for resource use, and (4) Facilitate external scientific approval of the NASA requirements. The modeling of microbial risk involves the evaluation of several key factors including hazard identification, crew exposure assessment, dose-response assessment, and risk characterization. Many of these factors are similar to conditions found on Earth; however, the spaceflight environment is very specialized as the inhabitants live in a small, semi-closed environment that is often dependent on regenerative life support systems. To further complicate modeling efforts, microbial dose

  12. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year's report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  13. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year`s report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  14. Phylogenetic analysis of a microbialite-forming microbial mat from a hypersaline lake of the Kiritimati atoll, Central Pacific.

    Science.gov (United States)

    Schneider, Dominik; Arp, Gernot; Reimer, Andreas; Reitner, Joachim; Daniel, Rolf

    2013-01-01

    On the Kiritimati atoll, several lakes exhibit microbial mat-formation under different hydrochemical conditions. Some of these lakes trigger microbialite formation such as Lake 21, which is an evaporitic, hypersaline lake (salinity of approximately 170‰). Lake 21 is completely covered with a thick multilayered microbial mat. This mat is associated with the formation of decimeter-thick highly porous microbialites, which are composed of aragonite and gypsum crystals. We assessed the bacterial and archaeal community composition and its alteration along the vertical stratification by large-scale analysis of 16S rRNA gene sequences of the nine different mat layers. The surface layers are dominated by aerobic, phototrophic, and halotolerant microbes. The bacterial community of these layers harbored Cyanobacteria (Halothece cluster), which were accompanied with known phototrophic members of the Bacteroidetes and Alphaproteobacteria. In deeper anaerobic layers more diverse communities than in the upper layers were present. The deeper layers were dominated by Spirochaetes, sulfate-reducing bacteria (Deltaproteobacteria), Chloroflexi (Anaerolineae and Caldilineae), purple non-sulfur bacteria (Alphaproteobacteria), purple sulfur bacteria (Chromatiales), anaerobic Bacteroidetes (Marinilabiacae), Nitrospirae (OPB95), Planctomycetes and several candidate divisions. The archaeal community, including numerous uncultured taxonomic lineages, generally changed from Euryarchaeota (mainly Halobacteria and Thermoplasmata) to uncultured members of the Thaumarchaeota (mainly Marine Benthic Group B) with increasing depth.

  15. Phylogenetic analysis of a microbialite-forming microbial mat from a hypersaline lake of the Kiritimati atoll, Central Pacific.

    Directory of Open Access Journals (Sweden)

    Dominik Schneider

    Full Text Available On the Kiritimati atoll, several lakes exhibit microbial mat-formation under different hydrochemical conditions. Some of these lakes trigger microbialite formation such as Lake 21, which is an evaporitic, hypersaline lake (salinity of approximately 170‰. Lake 21 is completely covered with a thick multilayered microbial mat. This mat is associated with the formation of decimeter-thick highly porous microbialites, which are composed of aragonite and gypsum crystals. We assessed the bacterial and archaeal community composition and its alteration along the vertical stratification by large-scale analysis of 16S rRNA gene sequences of the nine different mat layers. The surface layers are dominated by aerobic, phototrophic, and halotolerant microbes. The bacterial community of these layers harbored Cyanobacteria (Halothece cluster, which were accompanied with known phototrophic members of the Bacteroidetes and Alphaproteobacteria. In deeper anaerobic layers more diverse communities than in the upper layers were present. The deeper layers were dominated by Spirochaetes, sulfate-reducing bacteria (Deltaproteobacteria, Chloroflexi (Anaerolineae and Caldilineae, purple non-sulfur bacteria (Alphaproteobacteria, purple sulfur bacteria (Chromatiales, anaerobic Bacteroidetes (Marinilabiacae, Nitrospirae (OPB95, Planctomycetes and several candidate divisions. The archaeal community, including numerous uncultured taxonomic lineages, generally changed from Euryarchaeota (mainly Halobacteria and Thermoplasmata to uncultured members of the Thaumarchaeota (mainly Marine Benthic Group B with increasing depth.

  16. Pathogenesis of microbial keratitis.

    Science.gov (United States)

    Lakhundi, Sahreena; Siddiqui, Ruqaiyyah; Khan, Naveed Ahmed

    2017-03-01

    Microbial keratitis is a sight-threatening ocular infection caused by bacteria, fungi, and protist pathogens. Epithelial defects and injuries are key predisposing factors making the eye susceptible to corneal pathogens. Among bacterial pathogens, the most common agents responsible for keratitis include Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pneumonia and Serratia species. Fungal agents of corneal infections include both filamentous as well as yeast, including Fusarium, Aspergillus, Phaeohyphomycetes, Curvularia, Paecilomyces, Scedosporium and Candida species, while in protists, Acanthamoeba spp. are responsible for causing ocular disease. Clinical features include redness, pain, tearing, blur vision and inflammation but symptoms vary depending on the causative agent. The underlying molecular mechanisms associated with microbial pathogenesis include virulence factors as well as the host factors that aid in the progression of keratitis, resulting in damage to the ocular tissue. The treatment therefore should focus not only on the elimination of the culprit but also on the neutralization of virulence factors to minimize the damage, in addition to repairing the damaged tissue. A complete understanding of the pathogenesis of microbial keratitis will lead to the rational development of therapeutic interventions. This is a timely review of our current understanding of the advances made in this field in a comprehensible manner. Coupled with the recently available genome sequence information and high throughput genomics technology, and the availability of innovative approaches, this will stimulate interest in this field. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Microbial reduction of iodate

    Science.gov (United States)

    Councell, T.B.; Landa, E.R.; Lovley, D.R.

    1997-01-01

    The different oxidation species of iodine have markedly different sorption properties. Hence, changes in iodine redox states can greatly affect the mobility of iodine in the environment. Although a major microbial role has been suggested in the past to account for these redox changes, little has been done to elucidate the responsible microorganisms or the mechanisms involved. In the work presented here, direct microbial reduction of iodate was demonstrated with anaerobic cell suspensions of the sulfate reducing bacterium Desulfovibrio desulfuricans which reduced 96% of an initial 100 ??M iodate to iodide at pH 7 in 30 mM NaHCO3 buffer, whereas anaerobic cell suspensions of the dissimilatory Fe(III)-reducing bacterium Shewanella putrefaciens were unable to reduce iodate in 30 mM NaHCO3 buffer (pH 7). Both D. desulfuricans and S. putrefaciens were able to reduce iodate at pH 7 in 10 mM HEPES buffer. Both soluble ferrous iron and sulfide, as well as iron monosulfide (FeS) were shown to abiologically reduce iodate to iodide. These results indicate that ferric iron and/or sulfate reducing bacteria are capable of mediating both direct, enzymatic, as well as abiotic reduction of iodate in natural anaerobic environments. These microbially mediated reactions may be important factors in the fate and transport of 129I in natural systems.

  18. Impact of paleoclimate on the distribution of microbial communities in the subsurface sediment of the Dead Sea.

    Science.gov (United States)

    Thomas, C; Ionescu, D; Ariztegui, D

    2015-11-01

    A long sedimentary core has been recently retrieved from the Dead Sea Basin (DSB) within the framework of the ICDP-sponsored Dead Sea Deep Drilling Project. Contrasting climatic intervals were evident by distinctive lithological facies such as laminated aragonitic muds and evaporites. A geomicrobiological investigation was conducted in representative sediments of this core. To identify the microbial assemblages present in the sediments and their evolution with changing depositional environments through time, the diversity of the 16S rRNA gene was analyzed in gypsum, aragonitic laminae, and halite samples. The subsurface microbial community was largely dominated by the Euryarchaeota phylum (Archaea). Within the latter, Halobacteriaceae members were ubiquitous, probably favored by their 'high salt-in' osmotic adaptation which also makes them one of the rare inhabitants of the modern Dead Sea. Bacterial community members were scarce, emphasizing that the 'low salt-in' strategy is less suitable in this environment. Substantial differences in assemblages are observed between aragonitic sediments and gypsum-halite ones, independently of the depth and salinity. The aragonite sample, deposited during humid periods when the lake was stratified, consists mostly of the archaeal MSBL1 and bacterial KB1 Candidate Divisions. This consortium probably relies on compatible solutes supplied from the lake by halotolerant species present in these more favorable periods. In contrast, members of the Halobacteriaceae were the sole habitants of the gypsum-halite sediments which result from a holomictic lake. Although the biomass is low, these variations in the observed subsurface microbial populations appear to be controlled by biological conditions in the water column at the time of sedimentation, and subsequently by the presence or absence of stratification and dilution in the lake. As the latter are controlled by climatic changes, our data suggest a relationship between local

  19. Preparation and characterization of biocomposite film based on chitosan and kombucha tea as active food packaging

    DEFF Research Database (Denmark)

    Ashrafi, Azam; Jokar, Maryam

    2018-01-01

    work demonstrates that the chitosan/KT film not only maintains the quality of the minced beef but also, retards microbial growth significantly, extending the shelf life of the minced beef meat up to 3 days; thus, chitosan/KT film is a potential material for active food packaging....... chitosan and the polyphenol groups of KT. In a minced beef model, chitosan/KT film effectively served as an active packaging and extended the shelf life of the minced beef as manifested in the retardation of lipid oxidation and microbial growth from 5.36 to 2.11 log cfu gr−1 in 4 days storage. The present......An active film composed of chitosan and kombucha tea (KT) was successfully prepared using the solvent casting technique. The effect of incorporation of KT at the levels 1%–3% w/w on the physical and functional properties of chitosan film was investigated. The antimicrobial activity of chitosan...

  20. [Films in French.

    Science.gov (United States)

    Encyclopaedia Britannica, Inc., Chicago, IL.

    This list of approximately 100 educational films in French covers a wide variety of topics including films for use in social studies, language arts, humanities, physical and natural sciences, safety and health, and fine arts classes. Many films feature life patterns among particular ethnic groups. Catalogue numbers and sale prices of films in both…

  1. Biodegradation of poly(hydroxy butanoic acid) copolymer mulch films in soil

    Science.gov (United States)

    Kukade, Pranav

    Agricultural mulch films that are used to cover soil of crop rows contribute to earlier maturation of crops and higher yield. Incineration and landfill disposals are the most common means of disposal of the incumbent polyethylene (PE) mulch films; however, these are not environment friendly options. Biodegradable mulch films that can be rototilled into the soil after crop harvest are a promising alternative to offset problems such as landfill disposal, film retrieval and disposal costs. In this study, an in-house laboratory scale test method was developed in which the rate of disintegration, as a result of biodegradation of films based on polyhydroxybutanoic acid (PHB) copolymers was investigated in a soil environment using the residual weight loss method. The influence of soil composition, moisture levels in the soil, and industry-standard anti-microbial additive in the film composition on the rate of disintegration of PHB copolymer films was investigated. The soil composition has significant effect on the disintegration kinetics of PHB copolymer films, since the increasing compost levels in the soil lowered the rate of disintegration of the film. Also, with the increase in moisture level up to a threshold limit, the microbial activity and, hence, the rate of disintegration increased. Lastly, the developed lab-scale test protocol was found to be sensitive to even small concentrations of industry-standard antimicrobial additive in the film composition.

  2. Durable solar mirror films

    Science.gov (United States)

    O'Neill, Mark B.; Henderson, Andrew J.; Hebrink, Timothy J.; Katare, Rajesh K.; Jing, Naiyong; North, Diane; Peterson, Eric M.

    2017-02-14

    The present disclosure generally relates to durable solar mirror films, methods of making durable solar mirror films, and constructions including durable solar mirror films. In one embodiment, the present disclosure relates to a solar mirror film comprising: a multilayer optical film layer including having a coefficient of hygroscopic expansion of less than about 30 ppm per percent relative humidity; and a reflective layer having a coefficient of hygroscopic expansion.

  3. F and Ti doped silicate nanocomposite thin films for antimicrobial and easy clean applications.

    Science.gov (United States)

    Seo, YongSeong; Son, You-Hwan; Kim, Dae-Jin; Cho, Won-Je; Raj, C Justin; HyunYu, Kook

    2014-12-01

    Titanium isopropoxide (TIPO), tetraethyl orthosilicate (TEOS) and Fluoroalkylsilane (FAS) silane precursor were employed to coat transparent thin film on the glass substrate and these effectively prevents pollution on the glass from microorganisms. The each nanocomposition film was prepared by sol-gel method, the solution of nanocomposite was coated by spin coater with 1200 rpm for 30 sec and cured by thermal at 100 degrees C on glass which surface treated with Piranha solution. The nanocomposite films with highly self cleaning efficacy were fabricated and studied for various molar compositions of TEOS, TIPO and FAS. TEOS/TIPO film in glass substrate shows an optical transparency over 90% up to 30 mol% of TIPO in TEOS/TIPO composite films and also FAS incorporated up to 4 mol% onto TEOS/TIPO films. The anti-microbial efficiency of the nanocomposite film was improved 30% when it was exposed under UV light radiation than that in ambient condition.

  4. Microbial Cell Dynamics Lab (MCDL)

    Data.gov (United States)

    Federal Laboratory Consortium — The Microbial Cell Dynamics Laboratory at PNNL enables scientists to study the molecular details of microbes under relevant environmental conditions. The MCDL seeks...

  5. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Coates, J.D.; Chisholm, J.L.

    1993-05-01

    A multi-well microbially enhanced oil recovery field pilot has been performed in the Southeast Vassar Vertz Sand Unit in Payne County, Oklahoma. The primary emphasis of the experiment was preferential plugging of high permeability zones for the purpose of improving waterflood sweep efficiency. Studies were performed to determine reservoir chemistry, ecology, and indigenous bacteria populations. Growth experiments were used to select a nutrient system compatible with the reservoir that encouraged growth of a group of indigenous nitrate-using bacteria and inhibit growth of sulfate-reducing bacteria. A specific field pilot area behind an active line drive waterflood was selected. Surface facilities were designed and installed. Injection protocols of bulk nutrient materials were prepared to facilitate uniform distribution of nutrients within the pilot area. By the end of December, 1991, 82.5 tons (75.0 tonnes) of nutrients had been injected in the field. A tracer test identified significant heterogeneity in the SEVVSU and made it necessary to monitor additional production wells in the field. The tracer tests and changes in production behavior indicate the additional production wells monitored during the field trial were also affected. Eighty two and one half barrels (13.1 m[sup 3]) of tertiary oil have been recovered. Microbial activity has increased CO[sub 2] content as indicated by increased alkalinity. A temporary rise in sulfide concentration was experienced. These indicate an active microbial community was generated in the field by the nutrient injection. Pilot area interwell pressure interference test results showed that significant permeability reduction occurred. The interwell permeabilities in the pilot area between the injector and the three pilot production wells were made more uniform which indicates a successful preferential plugging enhanced oil recovery project.

  6. Versatility of microbial transglutaminase.

    Science.gov (United States)

    Strop, Pavel

    2014-05-21

    Although microbial transglutaminases (mTGs) were initially discovered to offset the cost of producing mammalian transglutaminases for food applications, they have quickly become important tools in research and biotechnology. Today, mTGs are utilized for a large number of applications to conjugate proteins and peptides to small molecules, polymers, surfaces, and DNA, as well as to other proteins. It is important to know how to maximize the advantages of the enzymatic approach and avoid undesired cross-linking. This review focuses on the versatility of transglutaminases in the field of bioconjugation and covers recent developments in utilizing mTG for generating antibody drug conjugates (ADCs) for therapeutic applications.

  7. Microbial bebop: creating music from complex dynamics in microbial ecology.

    Science.gov (United States)

    Larsen, Peter; Gilbert, Jack

    2013-01-01

    In order for society to make effective policy decisions on complex and far-reaching subjects, such as appropriate responses to global climate change, scientists must effectively communicate complex results to the non-scientifically specialized public. However, there are few ways however to transform highly complicated scientific data into formats that are engaging to the general community. Taking inspiration from patterns observed in nature and from some of the principles of jazz bebop improvisation, we have generated Microbial Bebop, a method by which microbial environmental data are transformed into music. Microbial Bebop uses meter, pitch, duration, and harmony to highlight the relationships between multiple data types in complex biological datasets. We use a comprehensive microbial ecology, time course dataset collected at the L4 marine monitoring station in the Western English Channel as an example of microbial ecological data that can be transformed into music. Four compositions were generated (www.bio.anl.gov/MicrobialBebop.htm.) from L4 Station data using Microbial Bebop. Each composition, though deriving from the same dataset, is created to highlight different relationships between environmental conditions and microbial community structure. The approach presented here can be applied to a wide variety of complex biological datasets.

  8. Magnetic core/shell nanoparticle thin films deposited by MAPLE: Investigation by chemical, morphological and in vitro biological assays

    Science.gov (United States)

    Cristescu, R.; Popescu, C.; Socol, G.; Iordache, I.; Mihailescu, I. N.; Mihaiescu, D. E.; Grumezescu, A. M.; Balan, A.; Stamatin, I.; Chifiriuc, C.; Bleotu, C.; Saviuc, C.; Popa, M.; Chrisey, D. B.

    2012-09-01

    We report on thin film deposition of nanostructured Fe3O4/oleic acid/ceftriaxone and Fe3O4/oleic acid/cefepime nanoparticles (core/shell/adsorption-shell) were fabricated by matrix assisted pulsed laser evaporation (MAPLE) onto inert substrates. The thin films were characterized by profilometry, Fourier transform infrared spectroscopy, atomic force microscopy, and investigated by in vitro biological assays. The biological properties tested included the investigation of the microbial viability and the microbial adherence to the glass coverslip nanoparticle film, using Gram-negative and Gram-positive bacterial strains with known antibiotic susceptibility behavior, the microbial adherence to the HeLa cells monolayer grown on the nanoparticle pellicle, and the cytotoxicity on eukaryotic cells. The proposed system, based on MAPLE, could be used for the development of novel anti-microbial materials or strategies for fighting pathogenic biofilms frequently implicated in the etiology of biofilm associated chronic infections.

  9. [Microbial sources of pigments].

    Science.gov (United States)

    Cañizares-Villanueva, R O; Ríos-Leal, E; Olvera Ramírez, R; Ponce Noyola, T; Márquez Rocha, F

    1998-01-01

    Pigments from natural sources has been obtained since long time ago, and their interest has increased due to the toxicity problems caused by those of synthetic origin. In this way the pigments from microbial sources are a good alternative. Some of more important natural pigments, are the carotenoids, flavonoids (anthocyanins) and some tetrapirroles (chloropyls, phycobilliproteins). Another group less important are the betalains and quinones. The carotenoids are molecules formed by isoprenoids units and the most important used as colorant are the alpha and beta carotene which are precursors of vitamin A, and some xantophylls as astaxanthin. The pigment more used in the industry is the beta-carotene which is obtained from some microalgae and cyanobacteria. The astaxanthin another important carotenoid is a red pigment of great commercial value, and it is used in the pharmaceutical feed and acuaculture industries. This pigments is mainly obtained from Phaffia rhodozyma and Haematococcus pluvialis and other organisms. The phycobilliproteins obtained from cyanobacteria and some group of algae, have recently been increased on the food industries. In the last years it has been used as fluorescent marker in biochemical assays. Our research group have carried out studies about the factors that improve the production of these pigments obtained from different microbial species as well as the methods for their extraction and application.

  10. Microbial biofilm formation and its consequences for the CELSS program

    Science.gov (United States)

    Mitchell, R.

    1994-01-01

    A major goal of the Controlled Ecology Life Support System (CELSS) program is to provide reliable and efficient life support systems for long-duration space flights. A principal focus of the program is on the growth of higher plants in growth chambers. These crops should be grown without the risk of damage from microbial contamination. While it is unlikely that plant pathogens will pose a risk, there are serious hazards associated with microorganisms carried in the nutrient delivery systems and in the atmosphere of the growth chamber. Our experience in surface microbiology showed that colonization of surfaces with microorganisms is extremely rapid even when the inoculum is small. After initial colonization extensive biofilms accumulate on moist surfaces. These microbial films metabolize actively and slough off continuously to the air and water. During plant growth in the CELSS program, microbial biofilms have the potential to foul sensors and to plug nutrient delivery systems. In addition both metabolic products of microbial growth and degradation products of materials being considered for use as nutrient reservoirs and for delivery are likely sources of chemicals known to adversly affect plant growth.

  11. Compositions of constructed microbial mats

    Science.gov (United States)

    Bender, Judith A.; Phillips, Peter C.

    1999-01-01

    Compositions and methods of use of constructed microbial mats, comprising cyanobacteria and purple autotrophic bacteria and an organic nutrient source, in a laminated structure, are described. The constructed microbial mat is used for bioremediation of different individual contaminants and for mixed or multiple contaminants, and for production of beneficial compositions and molecules.

  12. A microbial world within us

    NARCIS (Netherlands)

    Zoetendal, E.G.; Vaughan, E.E.; Vos, de W.M.

    2006-01-01

    The microbial world within us includes a vast array of gastrointestinal (GI) tract communities that play an important role in health and disease. Significant progress has been made in recent years in describing the intestinal microbial composition based on the application of 16S ribosomal RNA

  13. Microbial biofilms on facial prostheses

    NARCIS (Netherlands)

    Ariani, Nina; Vissink, Arjan; van Oort, Robert P.; Kusdhany, Lindawati; Djais, Ariadna; Rahardjo, Tri Budi W.; van der Mei, Henny C.; Krom, Bastiaan P.

    2012-01-01

    The composition of microbial biofilms on silicone rubber facial prostheses was investigated and compared with the microbial flora on healthy and prosthesis-covered skin. Scanning electron microscopy showed the presence of mixed bacterial and yeast biofilms on and deterioration of the surface of the

  14. Application of a puffer fish skin gelatin film containing Moringa oleifera Lam. leaf extract to the packaging of Gouda cheese.

    Science.gov (United States)

    Lee, Ka-Yeon; Yang, Hyun-Ju; Song, Kyung Bin

    2016-11-01

    This study aims to develop a puffer fish skin gelatin (PSG) film that contains Moringa oleifera Lam. leaf extract (ME) as a new biodegradable film. With the increase in ME concentration, the tensile strength and elongation at break of the PSG film increased, whereas the oxygen permeability and water vapor permeability decreased. In addition, the PSG film with ME exhibited antimicrobial activity against Listeria monocytogenes and antioxidant activity. To apply the ME-containing PSG film to food packaging, Gouda cheese was wrapped with the ME-containing PSG film. During storage, the cheese packaging with the ME-containing PSG film effectively inhibited the microbial growth and retarded the lipid oxidation of cheese compared with the control sample. Thus, the ME-containing PSG film can be used as an antimicrobial and antioxidative packaging material to improve the quality of food products.

  15. Hydrodynamics of microbial filter feeding

    DEFF Research Database (Denmark)

    Nielsen, Lasse Tor; Asadzadeh, Seyed Saeed; Dölger, Julia

    2017-01-01

    Microbial filter feeders are an important group of grazers, significant to the microbial loop, aquatic food webs, and biogeochemical cycling. Our understanding of microbial filter feeding is poor, and, importantly, it is unknown what force microbial filter feeders must generate to process adequate...... amounts of water. Also, the trade-off in the filter spacing remains unexplored, despite its simple formulation: A filter too coarse will allow suitably sized prey to pass unintercepted, whereas a filter too fine will cause strong flow resistance. We quantify the feeding flow of the filter......-feeding choanoflagellate Diaphanoeca grandis using particle tracking, and demonstrate that the current understanding of microbial filter feeding is inconsistent with computational fluid dynamics (CFD) and analytical estimates. Both approaches underestimate observed filtration rates by more than an order of magnitude...

  16. Preparation and Properties of Moisture-absorbing Film Impregnated with Polyacrylic Acid Partial Sodium Salt Material

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Youn Suk; Park, Insik [Yonsei University, Wonju (Korea, Republic of); Choi, Hong Yeol [CJ Cheiljedang, Seoul (Korea, Republic of)

    2014-08-15

    Moisture is a major factor causing the deteriorative physical change, microbial growth, and chemical reaction of the products. In this study, the moisture absorbing composite films have been prepared with moisture absorbing material of polyacrylic acid partial sodium salt (PAPSS) impregnated on LLDPE polymer for the functional packaging applications. The results showed that PAPSS impregnated film illustrated uniformly dispersed PAPSS particles in the LLDPE polymer matrix. The transparency of the PAPSS impregnated film decreased slightly at higher PAPSS concentrations. An increase in the PAPSS content for moisture-absorbing films showed a similar decrease in tensile strength, percent elongation at break, and tear strength. Their values of films impregnated with PAPSS of 0.5, 1, and 2% showed no significant difference. Meanwhile, 4% PAPSS films significantly decreased the values of mechanical properties compared to the films impregnated with different PAPSS levels. Values of the oxygen permeability and water vapor permeability for PAPSS impregnated films decreased significantly with greater PAPSS. The results indicate that 4% PAPSS impregnated in LLDPE films had high affinity of moisture absorbencies compared to the other films. The mathematical equation that best described the moisture sorption isotherm of each film sample was the GAB equation at 25 .deg. C. The crystallization and melting temperatures of PAPSS films were influenced by the addition of PAPSS material, but showed good thermal stability.

  17. Film som kunst

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    2013-01-01

    Films by artists induce scholars to work across art, film and cultural history. Accordingly, this article adopts an interdisciplinary approach to the British-Nigerian artist Yinka Shonibare’s film Un Ballo in Maschera (2004). The film is grounded in Shonibare’s unique use of African-print fabric...... in conjunction with references to European cultural and political history, but the film is also – it is alleged – rooted in Black British cinema and the transnational postcolonialism which emerged in the UK of the 1980s. The article starts with a general introduction to Shonibare’s art and the colonial...... connotations of the African-print fabric, which are also central to the critique of power in Un Ballo in Maschera. Its critical agenda is then analysed and put into historical perspective by relating the film to Black British film. A comparison with the Black Audio Film Collective’s key work Handsworth Songs...

  18. Defining Documentary Film

    DEFF Research Database (Denmark)

    Juel, Henrik

    2006-01-01

    A discussion of various attemts at defining documentary film regarding form, content, truth, stile, genre or reception - and a propoposal of a positive list of essential, but non-exclusive characteristica of documentary film......A discussion of various attemts at defining documentary film regarding form, content, truth, stile, genre or reception - and a propoposal of a positive list of essential, but non-exclusive characteristica of documentary film...

  19. Sputtered Thin Film Research

    Science.gov (United States)

    1976-02-01

    influences substrate heating and uniformity of the deposition Th. ing .50 L/sec in the milxitorr range. Use of the turbomolecular pump in place...evaluation of the films eposited. Prior to film deposition the wafers were degreased, boiled in nitric acid rinsed in high resitivity deionized...the shutters were opened and film depositxon was initiated. After film deposition, heat treatments in nitrogen, hydrogen and oxygen were investigated

  20. Monitoring Microbially Influenced Corrosion

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    Abstract Microbially influenced corrosion (MIC) of carbon steel may occur in media with microbiological activity of especially sulphate-reducing bacteria (SRB). The applicability and reliability of a number of corrosion monitoring techniques for monitoring MIC has been evaluated in experiments...... and diffusional effects and unreliable corrosion rates, when biofilm and ferrous sulphide corrosion products cover the steel surface. Corrosion rates can be overestimated by a factor of 10 to 100 by electrochemical techniques. Weight loss coupons and ER are recommended as necessary basic monitoring techniques....... EIS might be used for detection of MIC as the appearance of very large capacitances can be attributed to the combined ferrous sulphide and biofilm formation. Capacitance correlates directly with sulphide concentration in sterile sulphide media. Keywords: Corrosion monitoring, carbon steel, MIC, SRB...

  1. Drinking water microbial myths.

    Science.gov (United States)

    Allen, Martin J; Edberg, Stephen C; Clancy, Jennifer L; Hrudey, Steve E

    2015-01-01

    Accounts of drinking water-borne disease outbreaks have always captured the interest of the public, elected and health officials, and the media. During the twentieth century, the drinking water community and public health organizations have endeavored to craft regulations and guidelines on treatment and management practices that reduce risks from drinking water, specifically human pathogens. During this period there also evolved misunderstandings as to potential health risk associated with microorganisms that may be present in drinking waters. These misunderstanding or "myths" have led to confusion among the many stakeholders. The purpose of this article is to provide a scientific- and clinically-based discussion of these "myths" and recommendations for better ensuring the microbial safety of drinking water and valid public health decisions.

  2. Microbial desulfurization of dibenzothiophene

    Energy Technology Data Exchange (ETDEWEB)

    van Afferden, M.; Schacht, S.; Beyer, M.; Klein, J.

    1988-01-01

    Concerning the sulfur removal from coal before combustion there is considerable interest in microbial methods as pyrite oxidation and elimination of organically bound sulfur from coal. Using organic sulfur compounds relevant for coal the mechanism of desulfurization was investigated. The authors isolated a defined mixed culture (FODO) able to utilize dibenzothiophene as sole sulfur source for growth, while benzoate was used as carbon source. The mixed culture FODO consists of an Alcaligenes denitrificans subspecies and a Brevibacterium species. Two metabolites of the degradation and dibenzothiophene-5-dioxide. The subsequent degradation of dibenzothiophene-5-dioxide used as sole sulfur source results in a release of sulfate ions into the medium. The results suggest a sulfur specific oxidative mechanism for removal of sulfur from dibenzothiophene.

  3. New microbial growth factor

    Science.gov (United States)

    Bok, S. H.; Casida, L. E., Jr.

    1977-01-01

    A screening procedure was used to isolate from soil a Penicillium sp., two bacterial isolates, and a Streptomyces sp. that produced a previously unknown microbial growth factor. This factor was an absolute growth requirement for three soil bacteria. The Penicillium sp. and one of the bacteria requiring the factor, an Arthrobacter sp., were selected for more extensive study concerning the production and characteristics of the growth factor. It did not seem to be related to the siderochromes. It was not present in soil extract, rumen fluid, or any other medium component tested. It appears to be a glycoprotein of high molecular weight and has high specific activity. When added to the diets for a meadow-vole mammalian test system, it caused an increased consumption of diet without a concurrent increase in rate of weight gain.

  4. Getting into Film.

    Science.gov (United States)

    London, Mel

    This book describes the various aspects of the film industry and the many jobs related to filmmaking, stressing that no "formula" exists for finding a successful career in the film industry. Chapters provide information on production, writing for film, cinematography, editing, music, sound, animation and graphics, acting and modeling, the "unsung…

  5. Radiochromic film dosimetry

    CERN Document Server

    Xu Zhi Yong

    2002-01-01

    Radiochromic film dosimetry was developed to measure ionization irradiation dose for industry and medicine. At this time, there are no comprehensive guideline on the medical application, calibration method and densitometer system for medicine. The review gives update on Radiochromic film dosimetry used for medicine, including principles, film model and material, characteristics, calibration method, scanning densitometer system and medical application

  6. Microbial biosensors for environmental monitoring

    Directory of Open Access Journals (Sweden)

    David VOGRINC

    2015-12-01

    Full Text Available Microbial biosensors are analytical devices capable of sensing substances in the environment due to the specific biological reaction of the microorganism or its parts. Construction of a microbial biosensor requires knowledge of microbial response to the specific analyte. Linking this response with the quantitative data, using a transducer, is the crucial step in the construction of a biosensor. Regarding the transducer type, biosensors are divided into electrochemical, optical biosensors and microbial fuel cells. The use of the proper configuration depends on the selection of the biosensing element. With the use of transgenic E. coli strains, bioluminescence or fluorescence based biosensors were developed. Microbial fuel cells enable the use of the heterogeneous microbial populations, isolated from wastewater. Different microorganisms are used for different pollutants – pesticides, heavy metals, phenolic compounds, organic waste, etc. Biosensing enables measurement of their concentration and their toxic or genotoxic effects on the microbes. Increasing environmental awareness has contributed to the increase of interest for biomonitoring. Although technologies, such as bioinformatics and genetic engineering, allow us to design complex and efficient microbial biosensors for environmental pollutants, the transfer of the laboratory work to the field still remains a problem to solve.

  7. Effects of Edible Films Containing Procyanidin on the Preservation of Pork Meat during Chilled Storage.

    Science.gov (United States)

    Kim, Hyoun Wook; Jeong, Jin Young; Seol, Kuk-Hwan; Seong, Pil-Nam; Ham, Jun-Sang

    2016-01-01

    Procyanidins, which are natural antioxidants and antimicrobials found in grapes, enhance the quality and extend the shelf life of meat. We explored the effects of edible films incorporating procyanidins on pork loin stored for various times. Procyanidins (0, 0.1, and 0.3%, w/w) were incorporated into the edible films. We assessed meat color, pH, levels of volatile basic nitrogen (VBN) and 2-thiobarbituric acid-reactive substances (TBARS), and microbial populations for 14 d. The chromaticities and pH values of pork loin wrapped in film containing procyanidins (0.1% and 0.3%) generally increased (pedible film impregnated with procyanidins inhibits lipid oxidation and microbial growth, thereby enhancing the quality and shelf life of pork meat.

  8. Microbial diversity structure in acetate single chamber microbial fuel cell for electricity generation

    Directory of Open Access Journals (Sweden)

    Dena Z. Khater

    2017-06-01

    Full Text Available This study investigates the performance of acetate feed membrane less single chamber microbial fuel cell and physical characterization of the bio film present on the anode surface using Scanning Electron Microscope (SEM and 16S rRNA analyzer. The performance has been investigated using Teflon treated carbon paper with 0.3 mg/cm2 Pt/C loaded as a cathode and carbon paper as an anode. The maximum open circuit potential is noticed as 791 mV, the system successfully revealed a maximum power density of 86.1 mW m−2 at stable current density of 354 mA m−2 with high coulombic efficiency of 65% at maximum degradation rate of 96%. SEM showed the dense adherence of microorganisms on the anode. 16S rRNA sequencing results indicates phylogenetic mixture in the communities of anodic biofilm and there is no single dominant bacterial species. The dominant phyla are Firmicutes, Gamma Proteobacteria, Alpha Proteobacteria, Actinobacteria, with ten dominant microbial strains: Bacillus firmus, Shewanella profunda, Bacillus isronensis, Brevundimonas bullata, Pseudomonas putida, Planococcus citreus, Micrococcus endophyticus, Acinetobacter tandoii, Bacillus safensis and Shewanella xiamenensis.

  9. The microbial ecology of permafrost

    DEFF Research Database (Denmark)

    Jansson, Janet; Tas, Neslihan

    2014-01-01

    Permafrost constitutes a major portion of the terrestrial cryosphere of the Earth and is a unique ecological niche for cold-adapted microorganisms. There is a relatively high microbial diversity in permafrost, although there is some variation in community composition across different permafrost......-gas emissions. This Review describes new data on the microbial ecology of permafrost and provides a platform for understanding microbial life strategies in frozen soil as well as the impact of climate change on permafrost microorganisms and their functional roles....

  10. Defining Disturbance for Microbial Ecology.

    Science.gov (United States)

    Plante, Craig J

    2017-08-01

    Disturbance can profoundly modify the structure of natural communities. However, microbial ecologists' concept of "disturbance" has often deviated from conventional practice. Definitions (or implicit usage) have frequently included climate change and other forms of chronic environmental stress, which contradict the macrobiologist's notion of disturbance as a discrete event that removes biomass. Physical constraints and disparate biological characteristics were compared to ask whether disturbances fundamentally differ in microbial and macroorganismal communities. A definition of "disturbance" for microbial ecologists is proposed that distinguishes from "stress" and other competing terms, and that is in accord with definitions accepted by plant and animal ecologists.

  11. Antimicrobial activity of biopolymer–antibiotic thin films fabricated by advanced pulsed laser methods

    Energy Technology Data Exchange (ETDEWEB)

    Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest-Magurele (Romania); Popescu, C.; Dorcioman, G.; Miroiu, F.M.; Socol, G.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest-Magurele (Romania); Gittard, S.D.; Miller, P.R.; Narayan, R.J. [Biomedical Engineering, University of North Carolina and North Carolina State University, Chapel Hill, NC 27599-7575 (United States); Enculescu, M. [National Institute for Materials Physics, PO Box MG-7, Bucharest-Magurele (Romania); Chrisey, D.B. [Tulane University, Department of Physics and Engineering Physics, New Orleans, LA (United States)

    2013-08-01

    We report on thin film deposition by matrix assisted pulsed laser evaporation (MAPLE) of two polymer–drug composite thin film systems. A pulsed KrF* excimer laser source (λ = 248 nm, τ = 25 ns, ν = 10 Hz) was used to deposit composite thin films of poly(D,L-lactide) (PDLLA) containing several gentamicin concentrations. FTIR spectroscopy was used to demonstrate that MAPLE-transferred materials exhibited chemical structures similar to those of drop cast materials. Scanning electron microscopy data indicated that MAPLE may be used to fabricate thin films of good morphological quality. The activity of PDLLA–gentamicin composite thin films against Staphylococcus aureus bacteria was demonstrated using drop testing. The influence of drug concentration on microbial viability was also assessed. Our studies indicate that polymer–drug composite thin films prepared by MAPLE may be used to impart antimicrobial activity to implants, medical devices, and other contact surfaces.

  12. Antimicrobial activity of biopolymer-antibiotic thin films fabricated by advanced pulsed laser methods

    Science.gov (United States)

    Cristescu, R.; Popescu, C.; Dorcioman, G.; Miroiu, F. M.; Socol, G.; Mihailescu, I. N.; Gittard, S. D.; Miller, P. R.; Narayan, R. J.; Enculescu, M.; Chrisey, D. B.

    2013-08-01

    We report on thin film deposition by matrix assisted pulsed laser evaporation (MAPLE) of two polymer-drug composite thin film systems. A pulsed KrF* excimer laser source (λ = 248 nm, τ = 25 ns, ν = 10 Hz) was used to deposit composite thin films of poly(D,L-lactide) (PDLLA) containing several gentamicin concentrations. FTIR spectroscopy was used to demonstrate that MAPLE-transferred materials exhibited chemical structures similar to those of drop cast materials. Scanning electron microscopy data indicated that MAPLE may be used to fabricate thin films of good morphological quality. The activity of PDLLA-gentamicin composite thin films against Staphylococcus aureus bacteria was demonstrated using drop testing. The influence of drug concentration on microbial viability was also assessed. Our studies indicate that polymer-drug composite thin films prepared by MAPLE may be used to impart antimicrobial activity to implants, medical devices, and other contact surfaces.

  13. Pyrolyzed thin film carbon

    Science.gov (United States)

    Tai, Yu-Chong (Inventor); Liger, Matthieu (Inventor); Harder, Theodore (Inventor); Konishi, Satoshi (Inventor); Miserendino, Scott (Inventor)

    2010-01-01

    A method of making carbon thin films comprises depositing a catalyst on a substrate, depositing a hydrocarbon in contact with the catalyst and pyrolyzing the hydrocarbon. A method of controlling a carbon thin film density comprises etching a cavity into a substrate, depositing a hydrocarbon into the cavity, and pyrolyzing the hydrocarbon while in the cavity to form a carbon thin film. Controlling a carbon thin film density is achieved by changing the volume of the cavity. Methods of making carbon containing patterned structures are also provided. Carbon thin films and carbon containing patterned structures can be used in NEMS, MEMS, liquid chromatography, and sensor devices.

  14. Reading Lawyer Films

    OpenAIRE

    Elkins, James

    2012-01-01

    With the advent of film studies in the United States, there has been a growing interest in legal academic circles in lawyer, legal, and courtroom films. In Professor Elkins’s essay, we find a claim that Hollywood lawyer films have pedagogical value.With the emerging interest in lawyer and legal films, there is virtually nothing written about what or how films are to be taught, and what their value might be. Professor Elkins provides the basic axioms for a humanistic approach to reading lawyer...

  15. Thin film processes II

    CERN Document Server

    Kern, Werner

    1991-01-01

    This sequel to the 1978 classic, Thin Film Processes, gives a clear, practical exposition of important thin film deposition and etching processes that have not yet been adequately reviewed. It discusses selected processes in tutorial overviews with implementation guide lines and an introduction to the literature. Though edited to stand alone, when taken together, Thin Film Processes II and its predecessor present a thorough grounding in modern thin film techniques.Key Features* Provides an all-new sequel to the 1978 classic, Thin Film Processes* Introduces new topics, and sever

  16. Microbial Functional Diversity, Biomass and Activity as Affected by Soil Surface Mulching in a Semiarid Farmland.

    Directory of Open Access Journals (Sweden)

    Yufang Shen

    Full Text Available Mulching is widely used to increase crop yield in semiarid regions in northwestern China, but little is known about the effect of different mulching systems on the microbial properties of the soil, which play an important role in agroecosystemic functioning and nutrient cycling. Based on a 4-year spring maize (Zea mays L. field experiment at Changwu Agricultural and Ecological Experimental Station, Shaanxi, we evaluated the responses of soil microbial activity and crop to various management systems. The treatments were NMC (no mulching with inorganic N fertilizer, GMC (gravel mulching with inorganic N fertilizer, FMC (plastic-film mulching with inorganic N fertilizer and FMO (plastic-film mulching with inorganic N fertilizer and organic manure addition. The results showed that the FMO soil had the highest contents of microbial biomass carbon and nitrogen, dehydrogenase activity, microbial activity and Shannon diversity index. The relative use of carbohydrates and amino acids by microbes was highest in the FMO soil, whereas the relative use of polymers, phenolic compounds and amines was highest in the soil in the NMC soil. Compared with the NMC, an increased but no significant trend of biomass production and nitrogen accumulation was observed under the GMC treatment. The FMC and FMO led a greater increase in biomass production than GMC and NMC. Compare with the NMC treatment, FMC increased grain yield, maize biomass and nitrogen accumulation by 62.2, 62.9 and 86.2%, but no significant difference was found between the FMO and FMC treatments. Some soil biological properties, i.e. microbial biomass carbon, microbial biomass nitrogen, being sensitive to the mulching and organic fertilizer, were significant correlated with yield and nitrogen availability. Film mulching over gravel mulching can serve as an effective measure for crop production and nutrient cycling, and plus organic fertilization additions may thus have improvements in the biological

  17. Effects of Edible Films Containing Procyanidin on the Preservation of Pork Meat during Chilled Storage

    OpenAIRE

    Kim, Hyoun Wook; Jeong, Jin Young; Seol, Kuk-Hwan; Seong, Pil-Nam; Ham, Jun-Sang

    2016-01-01

    Procyanidins, which are natural antioxidants and antimicrobials found in grapes, enhance the quality and extend the shelf life of meat. We explored the effects of edible films incorporating procyanidins on pork loin stored for various times. Procyanidins (0, 0.1, and 0.3%, w/w) were incorporated into the edible films. We assessed meat color, pH, levels of volatile basic nitrogen (VBN) and 2-thiobarbituric acid-reactive substances (TBARS), and microbial populations for 14 d. The chromaticities...

  18. Microbial ecology-based engineering of Microbial Electrochemical Technologies.

    Science.gov (United States)

    Koch, Christin; Korth, Benjamin; Harnisch, Falk

    2017-08-14

    Microbial ecology is devoted to the understanding of dynamics, activity and interaction of microorganisms in natural and technical ecosystems. Bioelectrochemical systems represent important technical ecosystems, where microbial ecology is of highest importance for their function. However, whereas aspects of, for example, materials and reactor engineering are commonly perceived as highly relevant, the study and engineering of microbial ecology are significantly underrepresented in bioelectrochemical systems. This shortfall may be assigned to a deficit on knowledge and power of these methods as well as the prerequisites for their thorough application. This article discusses not only the importance of microbial ecology for microbial electrochemical technologies but also shows which information can be derived for a knowledge-driven engineering. Instead of providing a comprehensive list of techniques from which it is hard to judge the applicability and value of information for a respective one, this review illustrates the suitability of selected techniques on a case study. Thereby, best practice for different research questions is provided and a set of key questions for experimental design, data acquisition and analysis is suggested. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  19. Ceramic Composite Thin Films

    Science.gov (United States)

    Ruoff, Rodney S. (Inventor); Stankovich, Sasha (Inventor); Dikin, Dmitriy A. (Inventor); Nguyen, SonBinh T. (Inventor)

    2013-01-01

    A ceramic composite thin film or layer includes individual graphene oxide and/or electrically conductive graphene sheets dispersed in a ceramic (e.g. silica) matrix. The thin film or layer can be electrically conductive film or layer depending the amount of graphene sheets present. The composite films or layers are transparent, chemically inert and compatible with both glass and hydrophilic SiOx/silicon substrates. The composite film or layer can be produced by making a suspension of graphene oxide sheet fragments, introducing a silica-precursor or silica to the suspension to form a sol, depositing the sol on a substrate as thin film or layer, at least partially reducing the graphene oxide sheets to conductive graphene sheets, and thermally consolidating the thin film or layer to form a silica matrix in which the graphene oxide and/or graphene sheets are dispersed.

  20. Microbial Cell Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Doktycz, Mitchel John [ORNL; Sullivan, Claretta [Eastern Virginia Medical School; Mortensen, Ninell P [ORNL; Allison, David P [ORNL

    2011-01-01

    limitation on the maximum scan size (roughly 100 x 100 {mu}m) and the restricted movement of the cantilever in the Z (or height) direction. In most commercial AFMs, the Z range is restricted to roughly 10 {mu}m such that the height of cells to be imaged must be seriously considered. Nevertheless, AFM can provide structural-functional information at nanometer resolution and do so in physiologically relevant environments. Further, instrumentation for scanning probe microscopy continues to advance. Systems for high-speed imaging are becoming available, and techniques for looking inside the cells are being demonstrated. The ability to combine AFM with other imaging modalities is likely to have an even greater impact on microbiological studies. AFM studies of intact microbial cells started to appear in the literature in the 1990s. For example, AFM studies of Saccharomyces cerevisiae examined buddings cars after cell division and detailed changes related to cell growth processes. Also, the first AFM studies of bacterial biofilms appeared. In the late 1990s, AFM studies of intact fungal spores described clear changes in spore surfaces upon germination, and studies of individual bacterial cells were also described. These early bacterial imaging studies examined changes in bacterial morphology due to antimicrobial peptides exposure and bacterial adhesion properties. The majority of these early studies were carried out on dried samples and took advantage of the resolving power of AFM. The lack of cell mounting procedures presented an impediment for cell imaging studies. Subsequently, several approaches to mounting microbial cells have been developed, and these techniques are described later. Also highlighted are general considerations for microbial imaging and a description of some of the various applications of AFM to microbiology.

  1. Microbial hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, P.F.; Maness, P.C.; Martin, S. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1995-09-01

    Photosynthetic bacteria inhabit an anaerobic or microaerophilic world where H{sub 2} is produced and consumed as a shared intermediary metabolite. Within a given bacterial isolate there are as many as 4 to 6 distinct enzymes that function to evolve or consume H{sub 2}. Three of the H{sub 2}-evolving physiologies involving three different enzymes from photosynthetic bacteria have been examined in detail for commercial viability. Nitrogenase-mediated H{sub 2} production completely dissimilates many soluble organic compounds to H{sub 2} and CO{sub 2} at rates up to 131 {mu}mol H{sub 2}{sm_bullet}min{sup -1}{sm_bullet}g cdw{sup -1} and can remain active for up to 20 days. This metabolism is very energy intensive, however, which limits solar conversion efficiencies. Fermentative hydrogenase can produce H{sub 2} at rates of 440 {mu}mol{sm_bullet}min{sup -1}{sm_bullet}g cdw{sup -1} at low levels of irradiation over indefinite periods. The equilibrium for this activity is low (<0.15 atmospheres), thereby requiring gas sparging, vacuuming, or microbial scavenging to retain prolonged activity. Microbial H{sub 2} production from the CO component of synthesis or producer gases maximally reaches activities of 1.5 mmol{sm_bullet}min{sup -1}{sm_bullet}g cdw{sup -1}. Mass transport of gaseous CO into an aqueous bacterial suspension is the rate-limiting step. Increased gas pressure strongly accelerates these rates. Immobilized bacteria on solid supports at ambient pressures also show enhanced shift activity when the bulk water is drained away. Scaled-up bioreactors with 100-200 cc bed volume have been constructed and tested. The near-term goal of this portion of the project is to engineer and economically evaluate a prototype system for the biological production of H{sub 2} from biomass. The CO shift enables a positive selection technique for O{sub 2}-resistant, H{sub 2}-evolving bacterial enzymes from nature.

  2. MICROBIAL MATS - A JOINT VENTURE

    NARCIS (Netherlands)

    VANGEMERDEN, H

    Microbial mats characteristically are dominated by a few functional groups of microbes: cyanobacteria, colorless sulfur bacteria, purple sulfur bacteria, and sulfate-reducing bacteria. Their combined metabolic activities result in steep environmental microgradients, particularly of oxygen and

  3. Microbial factories for recombinant pharmaceuticals

    OpenAIRE

    Domingo-Espín Joan; Ferrer-Miralles Neus; Corchero José; Vázquez Esther; Villaverde Antonio

    2009-01-01

    Abstract Most of the hosts used to produce the 151 recombinant pharmaceuticals so far approved for human use by the Food and Drug Administration (FDA) and/or by the European Medicines Agency (EMEA) are microbial cells, either bacteria or yeast. This fact indicates that despite the diverse bottlenecks and obstacles that microbial systems pose to the efficient production of functional mammalian proteins, namely lack or unconventional post-translational modifications, proteolytic instability, po...

  4. Microbial genomes: Blueprints for life

    Energy Technology Data Exchange (ETDEWEB)

    Relman, David A.; Strauss, Evelyn

    2000-12-31

    Complete microbial genome sequences hold the promise of profound new insights into microbial pathogenesis, evolution, diagnostics, and therapeutics. From these insights will come a new foundation for understanding the evolution of single-celled life, as well as the evolution of more complex life forms. This report is an in-depth analysis of scientific issues that provides recommendations and will be widely disseminated to the scientific community, federal agencies, industry and the public.

  5. In-Drift Microbial Communities

    Energy Technology Data Exchange (ETDEWEB)

    D. Jolley

    2000-11-09

    As directed by written work direction (CRWMS M and O 1999f), Performance Assessment (PA) developed a model for microbial communities in the engineered barrier system (EBS) as documented here. The purpose of this model is to assist Performance Assessment and its Engineered Barrier Performance Section in modeling the geochemical environment within a potential repository drift for TSPA-SR/LA, thus allowing PA to provide a more detailed and complete near-field geochemical model and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near Field Environment (NFE) Revision 2 (NRC 1999). This model and its predecessor (the in-drift microbial communities model as documented in Chapter 4 of the TSPA-VA Technical Basis Document, CRWMS M and O 1998a) was developed to respond to the applicable KTIs. Additionally, because of the previous development of the in-drift microbial communities model as documented in Chapter 4 of the TSPA-VA Technical Basis Document (CRWMS M and O 1998a), the M and O was effectively able to resolve a previous KTI concern regarding the effects of microbial processes on seepage and flow (NRC 1998). This document supercedes the in-drift microbial communities model as documented in Chapter 4 of the TSPA-VA Technical Basis Document (CRWMS M and O 1998a). This document provides the conceptual framework of the revised in-drift microbial communities model to be used in subsequent performance assessment (PA) analyses.

  6. Biogeochemistry of Microbial Mats

    Science.gov (United States)

    DesMarais, David J.; DeVincenizi, D. (Technical Monitor)

    2002-01-01

    The hierarchical organization of microbial ecosystems determines the rates of processes that shape Earth's environment, define the stage upon which major evolutionary events occurred, and create biosignatures in sediments and atmospheres. In cyanobacterial mats, oxygenic photosynthesis provides energy, organic substrates and oxygen to the ecosystem. Incident light changes with depth in the mat, both in intensity and spectral composition, and counteracting gradients of oxygen and sulfide shape the chemical microenvironment. A combination of benefits and hazards of light, oxygen and sulfide promotes the allocation of the various essential mat processes between light and dark periods and to various depths in the mat. Microliters produce hydrogen, small organic acids, nitrogen and sulfur species. Such compounds fuel a flow of energy and electrons in these ecosystems and thus shape interactions between groups of microorganisms. Coordinated observations of population distribution, abundance, and activity for an entire community are making fundamental questions in ecology accessible. These questions address those factors that sustain the remarkable diversity of microorganisms that are now being revealed by molecular techniques. These questions also target the processes that shape the various kinds of biosignatures that we will seek, both in ancient rocks from Earth and Mars, and in atmospheres of distant planets beyond our Solar System.

  7. Microbial production of biovanillin

    Directory of Open Access Journals (Sweden)

    A. Converti

    2010-10-01

    Full Text Available This review aims at providing an overview on the microbial production of vanillin, a new alternative method for the production of this important flavor of the food industry, which has the potential to become economically competitive in the next future. After a brief description of the applications of vanillin in different industrial sectors and of its physicochemical properties, we described the traditional ways of providing vanillin, specifically extraction and chemical synthesis (mainly oxidation and compared them with the new biotechnological options, i.e., biotransformations of caffeic acid, veratraldehyde and mainly ferulic acid. In the second part of the review, emphasis has been addressed to the factors most influencing the bioproduction of vanillin, specifically the age of inoculum, pH, temperature, type of co-substrate, as well as the inhibitory effects exerted either by excess substrate or product. The final part of the work summarized the downstream processes and the related unit operations involved in the recovery of vanillin from the bioconversion medium.

  8. Film: Genres and Genre Theory

    DEFF Research Database (Denmark)

    Bondebjerg, Ib

    2015-01-01

    Genre is a concept used in film studies and film theory to describe similarities between groups of films based on aesthetic or broader social, institutional, cultural, and psychological aspects. Film genre shares similarities in form and style, theme, and communicative function. A film genre...

  9. Film Music. Factfile No. 8.

    Science.gov (United States)

    Elsas, Diana, Ed.; And Others

    Organizations listed here with descriptive information include film music clubs and music guilds and associations. These are followed by a representative list of schools offering film music and/or film sound courses. Sources are listed for soundtrack recordings, sound effects/production music, films on film music, and oral history programs. The…

  10. [Microbial geochemical calcium cycle].

    Science.gov (United States)

    Zavarzin, G A

    2002-01-01

    The participation of microorganisms in the geochemical calcium cycle is the most important factor maintaining neutral conditions on the Earth. This cycle has profound influence on the fate of inorganic carbon, and, thereby, on the removal of CO2 from the atmosphere. The major part of calcium deposits was formed in the Precambrian, when prokaryotic biosphere predominated. After that, calcium recycling based on biogenic deposition by skeletal organisms became the main process. Among prokaryotes, only a few representatives, e.g., cyanobacteria, exhibit a special calcium function. The geochemical calcium cycle is made possible by the universal features of bacteria involved in biologically mediated reactions and is determined by the activities of microbial communities. In the prokaryotic system, the calcium cycle begins with the leaching of igneous rock predominantly through the action of the community of organotrophic organisms. The release of carbon dioxide to the soil air by organotrophic aerobes leads to leaching with carbonic acid and soda salinization. Under anoxic conditions, of major importance is the organic acid production by primary anaerobes (fermentative microorganisms). Calcium carbonate is precipitated by secondary anaerobes (sulfate reducers) and to a smaller degree by methanogens. The role of the cyanobacterial community in carbonate deposition is exposed by stromatolites, which are the most common organo-sedimentary Precambrian structures. Deposition of carbonates in cyanobacterial mats as a consequence of photoassimilation of CO2 does not appear to be a significant process. It is argued that carbonates were deposited at the boundary between the "soda continent", which emerged as a result of subaerial leaching with carbonic acid, and the ocean containing Ca2+. Such ecotones provided favorable conditions for the development of the benthic cyanobacterial community, which was a precursor of stromatolites.

  11. Thin Film Processes

    CERN Document Server

    Vossen, John L.

    1991-01-01

    This sequel to the 1978 classic, Thin Film Processes, gives a clear, practical exposition of important thin film deposition and etching processes that have not yet been adequately reviewed. It discusses selected processes in tutorial overviews with implementation guide lines and an introduction to the literature. Though edited to stand alone, when taken together, Thin Film Processes II and its predecessor present a thorough grounding in modern thin film techniques. Key Features * Provides an all-new sequel to the 1978 classic, Thin Film Processes * Introduces new topics, and several key topics presented in the original volume are updated * Emphasizes practical applications of major thin film deposition and etching processes * Helps readers find the appropriate technology for a particular application

  12. Hypersaline Subsurface Microbial Communities from the Dead Sea Viewed from Their Metagenomes.

    Science.gov (United States)

    Thomas, C.; Ionescu, D.; Ariztegui, D.

    2014-12-01

    The Dead Sea Deep Drilling Project (DSDDP) is an international research initiative aiming to reconstruct the paleoenvironmental and paleoseismic history of the Dead Sea Basin (DSB) in the Levantine region. Within this framework, analysis of microbial communities intend to qualify the extent of life in this extreme environment, the factors allowing its development and their contribution to the sedimentary and geochemical record. The extreme chemistry of the Dead Sea prevents the use of common in situ imaging techniques leaving little information on the general activity of the subsurface biosphere. Cloning and metagenomic techniques have however been implemented at different levels of a 457 m deep core. Results suggest a differential development or survival of the microbial community along the sedimentary column. Reasons for such distribution remain unclear but cannot only be imparted to salinity. Poorly known communities (e.g. Candidate Divisions MSBL1 and KB1) with strong potential for adaptations to anoxic hypersaline environments are recovered in some intervals. Halobacteria classes generally dominate the assemblages. Metagenomic data allowed characterizing their presence in two evaporitic facies of the core (aragonite at 2.7 m and gypsum at 90.6 m below lake floor), where they exhibit both salt-in and salt-out strategies to cope with the high salinities of the Dead Sea. Metabolisms are also adapted to the high heavy metal concentrations and low nutrient availability in the sediment. Although more work is needed in order to infer the impact of these microorganisms on the sediment and element cycles, indices of methanogenesis, fermentation and sulfate reducing activity imply influence on the carbon and sulfur cycle of the Dead Sea subsurface. This is highlighted by traces of microbial degradation of organic matter viewed under SEM, and by the formation of euhedral Fe-S mineralizations as a result of reduction of sulfur. Overall, this work calls for the importance

  13. Horror films and psychiatry.

    Science.gov (United States)

    Friedman, Susan Hatters; Forcen, Fernando Espi; Shand, John Preston

    2014-10-01

    Horror films have been popular for generations. The purpose of this article is to illustrate psychiatric conditions, themes and practice seen in horror films. Horror films often either include psychiatrists as characters or depict (Hollywood's dangerous version of) serious mental illness. Demonic possession, zombies, and 'slasher' killers are described, as well as the horror genre's characterizations of psychiatrists. © The Royal Australian and New Zealand College of Psychiatrists 2014.

  14. Religion og film

    DEFF Research Database (Denmark)

    Hvithamar, Annika; Eskjær, Mikkel Fugl

    2007-01-01

    Artiklen søger at stipulere en ramme for analyse af religion og film. Dels ved at række ud over den blotte konstatering af tilstedeværelse af religiøse elementer i film, dels ved at anslå en række temaer, der kan anvendes til analyse af sådanne film (individualisering, (de-)sekularisering, banal...

  15. Den danske independent film

    DEFF Research Database (Denmark)

    Hansen, Kim Toft

    2014-01-01

    at producere film, og derved er filmproduktion potentielt gjort tilgængelig for en større gruppe personer som både afsender og modtager. For det fjerde implicerer diskussionen af de to film også genre- og stilmæssige spørgsmål om dansk filmkultur, fordi indiefilmen både i film og uden for filmene italesætter...

  16. Clinical careers film.

    Science.gov (United States)

    2015-09-01

    Those interested in developing clinical academic careers might be interested in a short animated film by Health Education England (HEE) and the National Institute for Health Research. The three-minute film, a frame from which is shown below, describes the sort of opportunities that are on offer to all professionals as part of the HEE's clinical academic careers framework. You can view the film on YouTube at tinyurl.com/pelb95c.

  17. Renaissance of the Film.

    Science.gov (United States)

    Bellone, Julius, Ed.

    The post-World War II period was one of the liveliest in the history of the cinema. This is a collection of 33 critical articles on some of the best films of the perd. Most of the essays explicate the themes and symbols of the films. The essays deal with these films: "The Apu Trilogy,""L'Avventura,""Balthazar,""Blow-Up,""Bonnie and Clyde," Citizen…

  18. Inactivation of E. Coli in Water Using Photocatalytic, Nanostructured Films Synthesized by Aerosol Routes

    Directory of Open Access Journals (Sweden)

    Pratim Biswas

    2013-03-01

    Full Text Available TiO2 nanostructured films were synthesized by an aerosol chemical vapor deposition (ACVD method with different controlled morphologies: columnar, granular, and branched structures for the photocatalytic inactivation of Escherichia coli (E. coli in water. Effects of film morphology and external applied voltage on inactivation rate were investigated. As-prepared films were characterized using scanning electron microscopy (SEM, transmission electron microscopy (TEM, X-ray diffractometry (XRD, and UV-VIS. Photocatalytic and photoelectrochemical inactivation of E. coli using as-prepared TiO2 films were performed under irradiation of UVA light (note: UVA has a low efficiency to inactivate E. coli. Inactivation rate constants for each case were obtained from their respective inactivation curve through a 2 h incubation period. Photocatalytic inactivation rate constants of E. coli are 0.02/min (using columnar films, and 0.08/min (using branched films. The inactivation rate constant for the columnar film was enhanced by 330% by applied voltage on the film while that for the branched film was increased only by 30%. Photocatalytic microbial inactivation rate of the columnar and the branched films were also compared taking into account their different surface areas. Since the majority of the UV radiation that reaches the Earth’s surface is UVA, this study provides an opportunity to use sunlight to efficiently decontaminate drinking water.

  19. Observation of Microorganisms in Milk after the Expiration Date Using Dry Rehydratable Film

    Science.gov (United States)

    Kim, Youngshin; Lim, Soo-Min; Lee, Il-Sun

    2013-01-01

    Cultivation of microorganisms such as fungi and bacteria is often not included in scientific inquiries conducted in school because of the difficulty of manufacturing a suitable medium. A method using dry rehydratable film to reduce the need to manufacture a suitable medium and shorten incubation time was developed as an efficient microbial testing…

  20. MICROBIAL SURFACTANTS IN ENVIRONMENTAL TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    T. P. Pirog

    2015-08-01

    Full Text Available It was shown literature and own experimental data concerning the use of microbial surface active glycolipids (rhamno-, sophoro- and trehalose lipids and lipopeptides for water and soil purification from oil and other hydrocarbons, removing toxic heavy metals (Cu2+, Cd2+, Ni2+, Pb2+, degradation of complex pollution (oil and other hydrocarbons with heavy metals, and the role of microbial surfactants in phytoremediation processes. The factors that limit the use of microbial surfactants in environmental technologies are discussed. Thus, at certain concentrations biosurfactant can exhibit antimicrobial properties and inhibit microorganisms destructing xenobiotics. Microbial biodegradability of surfactants may also reduce the effectiveness of bioremediation. Development of effective technologies using microbial surfactants should include the following steps: monitoring of contaminated sites to determine the nature of pollution and analysis of the autochthonous microbiota; determining the mode of surfactant introduction (exogenous addition of stimulation of surfactant synthesis by autochthonous microbiota; establishing an optimal concentration of surfactant to prevent exhibition of antimicrobial properties and rapid biodegradation; research both in laboratory and field conditions.

  1. Role of lactoferrin in the tear film.

    Science.gov (United States)

    Flanagan, J L; Willcox, M D P

    2009-01-01

    The surface of the eye provides an inert barrier against infection. Through its unique combination of antimicrobial action and anti-inflammatory activities lactoferrin (Lf) in the tear film plays an important role in the maintenance of ocular health. In order to maintain clarity the eye must provide immunological defense without immunopathology. Along with physical barriers, soluble plasma factors and other proteins such as lysozyme, Lf produced by the acinar cells of the lacrimal gland serves a number of roles in defense for this purpose. Lf in tears provides antimicrobial efficacy by binding free iron thus reducing the availability of iron necessary for microbial growth and survival as well as pathogenesis. Lf has been shown to inhibit biofilm formation and thus may play a role in protecting contact lens surfaces from colonization. Virus particles' entry into epithelial cells is inhibited by Lf while an excess of Lf in tear film is thought to limit the opportunistic Lf-mediated bridging of adenovirus and host cell that occurs in other tissues. Lf dampens the classical complement activation pathway by binding to markers of inflammation and immune activation while pathogen-associated molecular patterns such as lipopolysaccharide (LPS) are targeted by Lf for removal through tears and hydrodynamic flushing. This review focuses on the role of Lf in human tear film and its contribution to ocular health during contact lens wear.

  2. The Possibility of Film Criticism.

    Science.gov (United States)

    Poague, Leland; Cadbury, William

    1989-01-01

    Examines the role of critical language in film criticism. Compares and contrasts Monroe Beardsley's philosophy on film aesthetics with the New Criticism. Outlines some of the contributions Beardsley has made to the study of film criticism. (KM)

  3. Precambrian Skeletonized Microbial Eukaryotes

    Science.gov (United States)

    Lipps, Jere H.

    2017-04-01

    . Tintinnids first appear in the mid-Mesozoic, like other modern planktic groups, including planktic foraminifera, new types of radiolarians, and a host of skeletal micro-algae. Microbial eukaryotes track algal eukaryote and metazoan evolution—none or very few in the Precambrian, some in the early Paleozoic with radiations in the later Paleozoic, Mesozoic and Cenozoic, with extinctions ( 30) reducing their biodiversity at particular times in the fossil record—thus indicating strong environmental selection on all marine groups.

  4. Microbial metabolism of tholin

    Science.gov (United States)

    Stoker, C. R.; Boston, P. J.; Mancinelli, R. L.; Segal, W.; Khare, B. N.; Sagan, C.

    1990-05-01

    In this paper, we show that a wide variety of common soil bacteria are able to obtain their carbon and energy needs from tholin (a class of complex organic heteropolymers thought to be widely distributed through the solar system; in this case tholin was produced by passage of electrical discharge through a mixture of methane, ammonia, and water vapor). We have isolated aerobic, anaerobic, and facultatively anaerobic bacteria which are able to use tholin as a sole carbon source. Organisms which metabolize tholin represent a variety of bacterial genera including Clostridium, Pseudomonas, Bacillus, Acinetobacter, Paracoccus, Alcaligenes, Micrococcus, Cornebacterium, Aerobacter, Arthrobacter, Flavobacterium,and Actinomyces. Aerobic tholin-using bacteria were firrst isolated from soils containing unusual or sparse carbon sources. Some of these organisms were found to be facultatively anaerobic. Strictly anaerobic tholin-using bacteria were isolated from both carbon-rich and carbon-poor anaerobic lake muds. In addition, both aerobic and anaerobic tholin-using bacteria were isolated from common soil collected outside the laboratory building. Some, but not all, of the strains that were able to obtain carbon from tholin were also able to obtain their nitrogen requirements from tholin. Bacteria isolated from common soils were tested for their ability to obtain carbon from the water-soluble fraction, the ethanol-soluble fraction, and the water/ethanol-insoluble fraction of the tholin. Of the 3.5 × 10 7 bacteria isolated per gram of common soils, 1.7 0.5, and 0.2%, respectively, were able to obtaib their carbon requirements from the water-soluble fraction, the ethanol-soluble fraction and the water/ethanol-insoluble fraction of the tholin. The palatability of tholins to modern microbes may have implications for the early evolution of microbial life on Earth. Tholins may have formed the base of the food chain for an early heterotrophic biosphere before the evolution of

  5. Optical thin film devices

    Science.gov (United States)

    Mao, Shuzheng

    1991-11-01

    Thin film devices are applied to almost all modern scientific instruments, and these devices, especially optical thin film devices, play an essential role in the performances of the instruments, therefore, they are attracting more and more attention. Now there are numerous kinds of thin film devices and their applications are very diversified. The 300-page book, 'Thin Film Device and Applications,' by Prof. K. L. Chopra gives some general ideas, and my paper also outlines the designs, fabrication, and applications of some optical thin film devices made in my laboratory. Optical thin film devices have been greatly developed in the recent decades. Prof. A. Thelan has given a number of papers on the theory and techniques, Prof. H. A. Macleod's book, 'Thin Film Optical Filters,' has concisely concluded the important concepts of optical thin film devices, and Prof. J. A. Dobrowobski has proposed many successful designs for optical thin film devices. Recently, fully-automatic plants make it easier to produce thin film devices with various spectrum requirements, and some companies, such as Balzers, Leybold AG, Satis Vacuum AG, etc., have manufactured such kinds of coating plants for research or mass-production, and the successful example is the production of multilayer antireflection coatings with high stability and reproducibility. Therefore, it could be said that the design of optical thin film devices and coating plants is quite mature. However, we cannot expect that every problem has been solved, the R&D work still continues, the competition still continues, and new design concepts, new techniques, and new film materials are continually developed. Meanwhile, the high-price of fully-automatic coating plants makes unpopular, and automatic design of coating stacks is only the technique for optimizing the manual design according to the physical concepts and experience, in addition, not only the optical system, but also working environment should be taken into account when

  6. Initial treatment of microbial keratitis.

    Science.gov (United States)

    Blanton, C L; Rapuano, C J; Cohen, E J; Laibson, P R

    1996-04-01

    The common occurrence of failed medical treatment in microbial keratitis led us to investigate this phenomenon. We retrospectively reviewed all ulcers that presented to our department for 24 consecutive months. We classified each ulcer as either a therapeutic success or failure based on a precise definition of the response to initial antibiotic selection. We then analyzed multiple factors including: antibiotic selection, ophthalmic disease, ulcer characteristics, and management, to determine their significance in the success or failure in treating microbial keratitis. Complications were also examined. Important factors in failure were non-fortified antibiotics (P ulcers (P = 0.051) were of borderline significance. Sensitivity results reflect high sensitivity among successfully treated patients when appropriate antibiotics are chosen. This report provides insight into current practice patterns and potential means to improve success in managing microbial keratitis.

  7. Microbial Metagenomics: Beyond the Genome

    Science.gov (United States)

    Gilbert, Jack A.; Dupont, Christopher L.

    2011-01-01

    Metagenomics literally means “beyond the genome.” Marine microbial metagenomic databases presently comprise ˜400 billion base pairs of DNA, only ˜3% of that found in 1 ml of seawater. Very soon a trillion-base-pair sequence run will be feasible, so it is time to reflect on what we have learned from metagenomics. We review the impact of metagenomics on our understanding of marine microbial communities. We consider the studies facilitated by data generated through the Global Ocean Sampling expedition, as well as the revolution wrought at the individual laboratory level through next generation sequencing technologies. We review recent studies and discoveries since 2008, provide a discussion of bioinformatic analyses, including conceptual pipelines and sequence annotation and predict the future of metagenomics, with suggestions of collaborative community studies tailored toward answering some of the fundamental questions in marine microbial ecology.

  8. Towards a processual microbial ontology.

    Science.gov (United States)

    Bapteste, Eric; Dupré, John

    2013-03-01

    Standard microbial evolutionary ontology is organized according to a nested hierarchy of entities at various levels of biological organization. It typically detects and defines these entities in relation to the most stable aspects of evolutionary processes, by identifying lineages evolving by a process of vertical inheritance from an ancestral entity. However, recent advances in microbiology indicate that such an ontology has important limitations. The various dynamics detected within microbiological systems reveal that a focus on the most stable entities (or features of entities) over time inevitably underestimates the extent and nature of microbial diversity. These dynamics are not the outcome of the process of vertical descent alone. Other processes, often involving causal interactions between entities from distinct levels of biological organisation, or operating at different time scales, are responsible not only for the destabilisation of pre-existing entities, but also for the emergence and stabilisation of novel entities in the microbial world. In this article we consider microbial entities as more or less stabilised functional wholes, and sketch a network-based ontology that can represent a diverse set of processes including, for example, as well as phylogenetic relations, interactions that stabilise or destabilise the interacting entities, spatial relations, ecological connections, and genetic exchanges. We use this pluralistic framework for evaluating (i) the existing ontological assumptions in evolution (e.g. whether currently recognized entities are adequate for understanding the causes of change and stabilisation in the microbial world), and (ii) for identifying hidden ontological kinds, essentially invisible from within a more limited perspective. We propose to recognize additional classes of entities that provide new insights into the structure of the microbial world, namely "processually equivalent" entities, "processually versatile" entities, and

  9. Universality of human microbial dynamics

    Science.gov (United States)

    Bashan, Amir; Gibson, Travis E.; Friedman, Jonathan; Carey, Vincent J.; Weiss, Scott T.; Hohmann, Elizabeth L.; Liu, Yang-Yu

    2016-06-01

    Human-associated microbial communities have a crucial role in determining our health and well-being, and this has led to the continuing development of microbiome-based therapies such as faecal microbiota transplantation. These microbial communities are very complex, dynamic and highly personalized ecosystems, exhibiting a high degree of inter-individual variability in both species assemblages and abundance profiles. It is not known whether the underlying ecological dynamics of these communities, which can be parameterized by growth rates, and intra- and inter-species interactions in population dynamics models, are largely host-independent (that is, universal) or host-specific. If the inter-individual variability reflects host-specific dynamics due to differences in host lifestyle, physiology or genetics, then generic microbiome manipulations may have unintended consequences, rendering them ineffective or even detrimental. Alternatively, microbial ecosystems of different subjects may exhibit universal dynamics, with the inter-individual variability mainly originating from differences in the sets of colonizing species. Here we develop a new computational method to characterize human microbial dynamics. By applying this method to cross-sectional data from two large-scale metagenomic studies—the Human Microbiome Project and the Student Microbiome Project—we show that gut and mouth microbiomes display pronounced universal dynamics, whereas communities associated with certain skin sites are probably shaped by differences in the host environment. Notably, the universality of gut microbial dynamics is not observed in subjects with recurrent Clostridium difficile infection but is observed in the same set of subjects after faecal microbiota transplantation. These results fundamentally improve our understanding of the processes that shape human microbial ecosystems, and pave the way to designing general microbiome-based therapies.

  10. Thin Film & Deposition Systems (Windows)

    Data.gov (United States)

    Federal Laboratory Consortium — Coating Lab: Contains chambers for growing thin film window coatings. Plasma Applications Coating Lab: Contains chambers for growing thin film window coatings. Solar...

  11. Water depth penetration film test

    Science.gov (United States)

    Lockwood, H. E.; Perry, L.; Sauer, G. E.; Lamar, N. T.

    1974-01-01

    As part of the National Aeronautics and Space Administration Earth Resources Program, a comparative and controlled evaluation of nine film-filter combinations was completed to establish the relative effectiveness in recording water subsurface detail if exposed from an aerial platform over a typical water body. The films tested, with one exception, were those which prior was suggested had potential. These included an experimental 2-layer positive color film, a 2-layer (minus blue layer) film, a normal 3-layer color film, a panchromatic black-and-white film, and a black-and-white infrared film. Selective filtration was used with all films.

  12. Advanced microscopy of microbial cells

    DEFF Research Database (Denmark)

    Haagensen, Janus Anders Juul; Regenberg, Birgitte; Sternberg, Claus

    2011-01-01

    Growing awareness of heterogeneity in cells of microbial populations has emphasized the importance of advanced microscopy for visualization and understanding of the molecular mechanisms underlying cell-to-cell variation. In this review, we highlight some of the recent advances in confocal...... microscopy, super-resolution optical microscopy (STED, SIM, PALM) as well as atomic force microscopy and Raman spectroscopy. Using examples of bistability in microbial populations as well as biofilm development and differentiation in bacterial and yeast consortia, we demonstrate the importance of microscopy...

  13. Systems biology of Microbial Communities

    Energy Technology Data Exchange (ETDEWEB)

    Navid, A; Ghim, C; Fenley, A; Yoon, S; Lee, S; Almaas, E

    2008-04-11

    Microbes exist naturally in a wide range of environments, spanning the extremes of high acidity and high temperature to soil and the ocean, in communities where their interactions are significant. We present a practical discussion of three different approaches for modeling microbial communities: rate equations, individual-based modeling, and population dynamics. We illustrate the approaches with detailed examples. Each approach is best fit to different levels of system representation, and they have different needs for detailed biological input. Thus, this set of approaches is able to address the operation and function of microbial communities on a wide range of organizational levels.

  14. Children As Film Makers.

    Science.gov (United States)

    Lidstone, John; McIntosh, Don

    Based on the premise that film making can be of much greater value in education than is generally realized, this book tells the classroom teacher how to help children make their own films from beginning to end. A detailed text illustrated by drawings and photographs explains the basics of camera operation, editing, splicing, animation, titling,…

  15. Eesti film sai auhindu

    Index Scriptorium Estoniae

    2011-01-01

    Anu Auna film "Vahetus" võitis Rooma sõltumatu filmi festivalil (Rome Independent Film Festival) parima välismaise lühifilmi preemia ning Olga ja Priit Pärna "Elu ilma Gabriella Ferrita" Lissaboni animafilmide festivalil Monstra eripreemia

  16. FAA Film Catalog.

    Science.gov (United States)

    Federal Aviation Administration (DOT), Washington, DC.

    Some 75 films from the U.S. Department of Transportation's Federal Aviation Administration are listed in this catalog. Topics dealt with include aerodynamics, airports, aviation history and careers, flying clubs, navigation and weather. Most of the films are 16mm sound and color productions. Filmstrips requiring a 35mm projector and phonograph or…

  17. On Teaching Ethnographic Film

    Science.gov (United States)

    Clarfield, Geoffrey

    2013-01-01

    The author of this article, a developmental anthropologist, illustrates how the instructor can use ethnographic films to enhance the study of anthropology and override notions about the scope and efficacy of Western intervention in the Third World, provided the instructor places such films in their proper historical and cultural context. He…

  18. Film, Neuroaesthetics, and Empathy

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh; Kramer, Mette

    2014-01-01

    The article analyzes the link between film viewing and human 'ultra-sociality' (Boyd and Richardson 1998), describing how empathy is supported by mirror resonances but also modified by appraisal mechanisms and how emotions are communicated, It further discusses how 'attainment' to film builds...

  19. Abstract Film and Beyond.

    Science.gov (United States)

    Le Grice, Malcolm

    A theoretical and historical account of the main preoccupations of makers of abstract films is presented in this book. The book's scope includes discussion of nonrepresentational forms as well as examination of experiments in the manipulation of time in films. The ten chapters discuss the following topics: art and cinematography, the first…

  20. Malaysian Cinema, Asian Film

    NARCIS (Netherlands)

    Heide, van der William

    2002-01-01

    This title series departs from traditional studies of national cinema by accentuating the intercultural and intertextual links between Malaysian films and Asian (as well as European and American) film practices. Using cross-cultural analysis, the author characterizes Malaysia as a pluralist society

  1. Protolytic carbon film technology

    Energy Technology Data Exchange (ETDEWEB)

    Renschler, C.L.; White, C.A.

    1996-04-01

    This paper presents a technique for the deposition of polyacrylonitrile (PAN) on virtually any surface allowing carbon film formation with only the caveat that the substrate must withstand carbonization temperatures of at least 600 degrees centigrade. The influence of processing conditions upon the structure and properties of the carbonized film is discussed. Electrical conductivity, microstructure, and morphology control are also described.

  2. What Is Film Phenomenology?

    NARCIS (Netherlands)

    Hanich, Julian; Ferencz-Flatz, Christian

    2016-01-01

    In this article Christian Ferencz-Flatz and I try to give an answer to the question what film phenomenology actually is. We proceed in three steps. First, we provide a survey of five different research practices within current film phenomenological writing: We call them excavation, explanation,

  3. Microbial volatile compounds alter the soil microbial community.

    Science.gov (United States)

    Yuan, Jun; Zhao, Mengli; Li, Rong; Huang, Qiwei; Raza, Waseem; Rensing, Christopher; Shen, Qirong

    2017-10-01

    Volatile organic compounds (VOCs) from soil bacteria are likely to have an important role in the interactions among soil microorganisms. However, their effects on the soil microbial community have not been extensively studied. In this study, the effect of bacterial VOCs generated by growing Bacillus amyloliquefaciens NJN-6 on modified MS medium on soil microbial community was evaluated. B. amyloliquefaciens NJN-6 was able to produce 48 volatile compounds as determined by solid-phase microextraction-GC/MS. MiSeq sequencing data showed that bacterial VOCs could alter the composition of both soil bacterial and soil fungal communities and could decrease the alpha-diversity of the soil microbial community. Taxonomic analysis revealed that bacterial VOCs significantly increased the relative abundance of Proteobacteria, Bacteroidetes, and Firmicutes. Moreover, bacterial VOCs significantly increased the relative abundance of Ascomycota. The qPCR data showed that bacterial VOCs of strain NJN-6 decreased the soil fungal biomass and increased the soil bacterial biomass. Further evaluation of the effect of bacterial VOCs on functional genes revealed that VOCs could reduce the copies of nifH, nirS, and a gene encoding nonribosomal peptide synthase, while increasing the copy number of the ammonium-oxidizing bacteria gene. The effect on gene encoding polyketide synthase was insignificant. Results from this study indicated that bacterial VOCs could influence the soil microbial community as well as functional gene abundance.

  4. Conceiving Landscape through Film

    DEFF Research Database (Denmark)

    Farsø, Mads; Munck Petersen, Rikke

    2015-01-01

    This article shows how the media of film can be integrated, explored and can add value to architectural design studios and practice. It elucidates how film may offer an alternative position in architecture, where landscapes and cities are thought, planned and developed in closer relation...... to their spatial and sensory effects on humans. It underscores that the film camera can work as a kind of amplifier of how we, with our bodies, perceive space and project space. In the “Landscape Film” Studio at University of Copenhagen the film medium was tested as a combined registration and design tool...... for a new Nature Park south of Copenhagen. The final studio films and designs show how resonate recordings of sound, time and a bodily presence may simulate an Einfühling that inspires an alternative architecture of relations: the ambient, the changeable and the volatile. They also emphasize that an ability...

  5. Microbial Heat Recovery Cell (MHRC) System Concept

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-09-01

    This factsheet describes a project that aimed to develop a microbial heat recovery cell (MHRC) system that combines a microbial reverse electrodialysis technology with waste heat recovery to convert industrial effluents into electricity and hydrogen.

  6. Microbial community structure elucidates performance of Glyceria maxima plant microbial fuel cell

    NARCIS (Netherlands)

    Timmers, R.A.; Rothballer, M.; Strik, D.P.B.T.B.; Engel, M.; Schulz, M.; Hartmann, A.; Hamelers, H.V.M.; Buisman, C.J.N.

    2012-01-01

    The plant microbial fuel cell (PMFC) is a technology in which living plant roots provide electron donor, via rhizodeposition, to a mixed microbial community to generate electricity in a microbial fuel cell. Analysis and localisation of the microbial community is necessary for gaining insight into

  7. Magnetic core/shell nanoparticle thin films deposited by MAPLE: Investigation by chemical, morphological and in vitro biological assays

    Energy Technology Data Exchange (ETDEWEB)

    Cristescu, R., E-mail: rodica.cristescu@inflpr.ro [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest-Magurele (Romania); Popescu, C.; Socol, G.; Iordache, I.; Mihailescu, I.N. [National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, P.O. Box MG-36, Bucharest-Magurele (Romania); Mihaiescu, D.E.; Grumezescu, A.M. [Faculty of Applied Chemistry and Materials Science, ' Politehnica' University of Bucharest, 1-7 Polizu Street, 011061 Bucharest (Romania); Balan, A.; Stamatin, I. [University of Bucharest, 3Nano-SAE Research Center, PO Box MG-38, Bucharest-Magurele (Romania); Chifiriuc, C. [Faculty of Biology, University of Bucharest, Microbiology Immunology Department, Aleea Portocalilor 1-3, Sector 5, 77206 Bucharest (Romania); Bleotu, C. [Stefan S. Nicolau Institute of Virology, 285 Mihai Bravu, 030304 Bucharest (Romania); Saviuc, C.; Popa, M. [Faculty of Biology, University of Bucharest, Microbiology Immunology Department, Aleea Portocalilor 1-3, Sector 5, 77206 Bucharest (Romania); Chrisey, D.B. [Rensselaer Polytechnic Institute, School of Engineering, Departments of Materials Science and Biomedical Engineering, Troy, 12180-3590, NY (United States)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer We deposit magnetic Fe{sub 3}O{sub 4}/oleic acid/cephalosporin nanoparticle thin films by MAPLE. Black-Right-Pointing-Pointer Thin films have a chemical structure similar to the starting material. Black-Right-Pointing-Pointer Cephalosporins have an additive effect on the grain size and induce changes in grain shape. Black-Right-Pointing-Pointer MAPLE can be used to develop novel strategies for fighting medical biofilms associated with chronic infections. - Abstract: We report on thin film deposition of nanostructured Fe{sub 3}O{sub 4}/oleic acid/ceftriaxone and Fe{sub 3}O{sub 4}/oleic acid/cefepime nanoparticles (core/shell/adsorption-shell) were fabricated by matrix assisted pulsed laser evaporation (MAPLE) onto inert substrates. The thin films were characterized by profilometry, Fourier transform infrared spectroscopy, atomic force microscopy, and investigated by in vitro biological assays. The biological properties tested included the investigation of the microbial viability and the microbial adherence to the glass coverslip nanoparticle film, using Gram-negative and Gram-positive bacterial strains with known antibiotic susceptibility behavior, the microbial adherence to the HeLa cells monolayer grown on the nanoparticle pellicle, and the cytotoxicity on eukaryotic cells. The proposed system, based on MAPLE, could be used for the development of novel anti-microbial materials or strategies for fighting pathogenic biofilms frequently implicated in the etiology of biofilm associated chronic infections.

  8. Microbially produced phytotoxins and plant disease management ...

    African Journals Online (AJOL)

    The knowledge of the inactivation of microbial toxins has led to the use of microbial enzymes to inactivate phytotoxins thereby reducing incidence and severity of disease induced by microbial toxins. Considering the increasing awareness of herbicide resistance, and the restriction of the use of chemical pesticides in ...

  9. Microbial incorporation of nitrogen in stream detritus

    Science.gov (United States)

    Diane M. Sanzone; Jennifer L. Tank; Judy L. Meyer; Patrick J. Mulholland; Stuart E.G. Findlay

    2001-01-01

    We adapted the chloroform fumigation method to determine microbial nitrogen (N) and microbial incorporation of 15N on three common substrates [leaves, wood and fine benthic organic matter (FBOM)] in three forest streams. We compared microbial N and 15 content of samples collected during a 6-week15N-NH...

  10. Film Theory and Hugo Munsterberg's "The Film": A Psychological Study.

    Science.gov (United States)

    Wicclair, Mark R.

    1978-01-01

    Hugo Munsterberg's "The Film: A Psychological Study" is one of the earliest essays in the area of film theory. Unfortunately, it has remained relatively unknown since its publication in 1916. The author discusses two concepts raised by Munsterberg: the contrast between films in the theatrical mode and films in the cinematic mode.…

  11. Advanced Microscopy of Microbial Cells

    DEFF Research Database (Denmark)

    Haagensen, Janus Anders Juul; Regenberg, Birgitte; Sternberg, Claus

    2011-01-01

    Growing awareness of heterogeneity in cells of microbial populations has emphasized the importance of advanced microscopy for visualization and understanding of the molecular mechanisms underlying cell-to-cell variation. In this review, we highlight some of the recent advances in confocal...... for visualization of variation between cells in phenotypic traits such as gene expression....

  12. Towards a microbial thermoelectric cell.

    Directory of Open Access Journals (Sweden)

    Raúl Rodríguez-Barreiro

    Full Text Available Microbial growth is an exothermic process. Biotechnological industries produce large amounts of heat, usually considered an undesirable by-product. In this work, we report the construction and characterization of the first microbial thermoelectric cell (MTC, in which the metabolic heat produced by a thermally insulated microbial culture is partially converted into electricity through a thermoelectric device optimized for low ΔT values. A temperature of 41°C and net electric voltage of around 250-600 mV was achieved with 1.7 L baker's yeast culture. This is the first time microbial metabolic energy has been converted into electricity with an ad hoc thermoelectric device. These results might contribute towards developing a novel strategy to harvest excess heat in the biotechnology industry, in processes such as ethanol fermentation, auto thermal aerobic digestion (ATAD or bioremediation, which could be coupled with MTCs in a single unit to produce electricity as a valuable by-product of the primary biotechnological product. Additionally, we propose that small portable MTCs could be conceived and inoculated with suitable thermophilic of hyperthermophilic starter cultures and used for powering small electric devices.

  13. System for detecting microbial contamination

    NARCIS (Netherlands)

    Gerritse, J.; Groenestijn, J.W.; Zegers, N.D.

    2009-01-01

    The present invention relates to a system for detecting microbial contamination of a liquid specimen comprising a device for concentrating micro-organisms from a liquid specimen, having (i) a hypobaric chamber, (ii) a filter housing comprising a liquid-permeable bed of an adsorbent material and

  14. Ion-Pumping Microbial Rhodopsins

    Directory of Open Access Journals (Sweden)

    Hideki eKandori

    2015-09-01

    Full Text Available Rhodopsins are light-sensing proteins used in optogenetics. The word rhodopsin originates from the Greek words rhodo and opsis, indicating rose and sight, respectively. Although the classical meaning of rhodopsin is the red-colored pigment in our eyes, the modern meaning of rhodopsin encompasses photoactive proteins containing a retinal chromophore in animals and microbes. Animal and microbial rhodopsins possess 11-cis and all-trans retinal, respectively, to capture light in seven transmembrane α-helices, and photoisomerizations into all-trans and 13-cis forms, respectively, initiate each function. Ion-transporting proteins can be found in microbial rhodopsins, such as light-gated channels and light-driven pumps, which are the main tools in optogenetics. Light-driven pumps, such as archaeal H+ pump bacteriorhodopsin (BR and Cl- pump halorhodopsin (HR, were discovered in the 1970s, and their mechanism has been extensively studied. On the other hand, different kinds of H+ and Cl- pumps have been found in marine bacteria, such as proteorhodopsin (PR and Fulvimarina pelagi rhodopsin (FR, respectively. In addition, a light-driven Na+ pump was found, Krokinobacter eikastus rhodopsin 2 (KR2. These light-driven ion-pumping microbial rhodopsins are classified as DTD, TSA, DTE, NTQ and NDQ rhodopsins for BR, HR, PR, FR and KR2, respectively. Recent understanding of ion-pumping microbial rhodopsins is reviewed in this paper.

  15. Physicochemical and antifungal properties of bio-nanocomposite film based on gelatin-chitin nanoparticles.

    Science.gov (United States)

    Sahraee, Samar; Milani, Jafar M; Ghanbarzadeh, Babak; Hamishehkar, Hamed

    2017-04-01

    The gelatin-based nanocomposite films containing chitin nanoparticles (N-chitin) with concentrations of 0, 3, 5 and 10% were prepared and their physical, thermal and anti-microbial properties were investigated. Scanning electron microscopy (SEM) micrographs showed that N-chitin size distribution was around 60-70nm which dispersed appropriately at low concentration in gelatin matrix. The results showed that incorporation of N-chitin significantly influenced apparent color and transparency of the gelatin films. The reduced water vapor permeability (WVP) and solubility and higher surface hydrophobicity of the nanocomposite films were obtained by enhancing N-chitin concentration in film formulation. The use of N-chitin up to 5% concentration in the gelatin based nanocomposite film led to improved mechanical properties. Also, the results of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) confirmed improved stability of nanocomposite films against melting and degradation at high temperatures in comparison to neat gelatin film. The well compatibility of chitin nanoparticles with gelatin polymer was concluded from Fourier transform infrared (FTIR) spectra and X-ray diffraction (XRD) plots. Finally, the gelatin based nanocomposite films had anti-fungal properties against Aspergillus niger in the contact surface zone. Increasing the concentration of N-chitin up to 5% enlarged inhibition zone diameter, but the nanocomposite film containing 10% N-chitin showed smaller inhibition zone. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Intermetallic semiconducting films

    CERN Document Server

    Wieder, H H

    1970-01-01

    Intermetallic Semiconducting Films introduces the physics and technology of AшВv compound films. This material is a type of a polycrystalline semiconductor that is used for galvanomagnetic device applications. Such material has a high electron mobility that is ideal for generators and magnetoresistors. The book discusses the available references on the preparation and identification of the material. An assessment of its device applications and other possible use is also enumerated. The book describes the structures and physical parts of different films. A section of the book covers the three t

  17. Nopal cactus film

    Science.gov (United States)

    Toxqui-López, S.; Olivares-Pérez, A.; Fuentes-Tapia, I.; Conde-Cuatzo, María. G.

    2017-03-01

    Nopal mucilage potentially has certain properties required for the preparation biofilms which can be used as holographic replication recording medium. In this study, mucilage from nopal was extracted and characterized by its ability to form films under different concentration with polyvinyl alcohol. The transmission holographic diffraction gratings (master) were replicated into nopal films. The results showed good diffraction efficiencies. Mucilage from nopal could represent a good option for the development of films to replication holographic, owing to; its low cost and its compatibility with the environmental.

  18. Ultrahard carbon nanocomposite films

    Energy Technology Data Exchange (ETDEWEB)

    SIEGAL,MICHAEL P.; TALLANT,DAVID R.; PROVENCIO,PAULA P.; OVERMYER,DONALD L.; SIMPSON,REGINA L.; MARTINEZ-MIRANDA,L.J.

    2000-01-27

    Modest thermal annealing to 600 C of diamondlike amorphous-carbon (a-C) films grown at room temperature results in the formation of carbon nanocomposites with hardness similar to diamond. These nanocomposite films consist of nanometer-sized regions of high density a-C embedded in an a-C matrix with a reduced density of 5--10%. The authors report on the evolution of density and bonding topologies as a function of annealing temperature. Despite a decrease in density, film hardness actually increases {approximately} 15% due to the development of the nanocomposite structure.

  19. A Film Guide on China.

    Science.gov (United States)

    Wiley, Christopher J., Ed.

    Over 80 films are listed in this annotated film guide on China. Designed to help educators select films about China, each entry contains a short annotation which gives a capsule and sometimes evaluative summary of film content. The booklet is divided into four sections on China before and after 1949, Taiwan, and Chinese culture. Each listing…

  20. Edible films and coatings: Sources, properties and application

    Directory of Open Access Journals (Sweden)

    Šuput Danijela Z.

    2015-01-01

    Full Text Available In order to extend product shelf life while preserving the quality scientific attention focused to biopolymers research that are base for edible films and coatings production. Another major advantage of this kind of food packaging is their eco-friendly status because biopolymers do not cause environmental problems as packaging materials derived from non-renewable energy sources do. Objective of this work was to review recently studied edible films and coatings - their sources, properties and possible application. As sources for edible biopolymers were highlighted polysaccharides, proteins and lipids. The most characteristic subgroups from each large group of compounds were selected and described regarding possible physical and mechanical protection; migration, permeation, and barrier functions. The most important biopolymers characteristic is possibility to act as active substance carriers and to provide controlled release. In order to achieve active packaging functions emulsifiers, antioxidants and antimicrobial agents can also be incorporated into film-forming solutions in order to protect food products from oxidation and microbial spoilage, resulting in quality improvement and enhanced safety. The specific application where edible films and coatings have potential to replace some traditional polymer packaging are explained. It can be concluded that edible films and coatings must be chosen for food packaging purpose according to specific applications, the types of food products, and the major mechanisms of quality deterioration.

  1. Toward Understanding, Managing, and Protecting Microbial Ecosystems

    Science.gov (United States)

    Bodelier, Paul L. E.

    2011-01-01

    Microbial communities are at the very basis of life on earth, catalyzing biogeochemical reactions driving global nutrient cycles. However, unlike for plants and animals, microbial diversity is not on the biodiversity–conservation agenda. The latter, however, would imply that microbial diversity is not under any threat by anthropogenic disturbance or climate change. This maybe a misconception caused by the rudimentary knowledge we have concerning microbial diversity and its role in ecosystem functioning. This perspective paper identifies major areas with knowledge gaps within the field of environmental microbiology that preclude a comprehension of microbial ecosystems on the level we have for plants and animals. Opportunities and challenges are pointed out to open the microbial black box and to go from descriptive to predictive microbial ecology. PMID:21747797

  2. Towards understanding, managing and protecting microbial ecosystems

    Directory of Open Access Journals (Sweden)

    Paul eBodelier

    2011-04-01

    Full Text Available Microbial communities are at the very basis of life on earth, catalysing biogeochemical reactions driving global nutrient cycles. However, unlike for plants and animals, microbial diversity is not on the biodiversity conservation agenda. The latter, however, would imply that microbial diversity is not under any threat by anthropogenic disturbance or climate change. This maybe a misconception caused by the rudimentary knowledge we have concerning microbial diversity and its role in ecosystem functioning. This perspective paper indentifies major areas with knowledge gaps within the field of environmental microbiology that preclude a comprehension of microbial ecosystems on the level we have for plants and animals. Opportunities and challenges are pointed out to open the microbial black box and to go from descriptive to predictive microbial ecology.

  3. Toward understanding, managing, and protecting microbial ecosystems.

    Science.gov (United States)

    Bodelier, Paul L E

    2011-01-01

    Microbial communities are at the very basis of life on earth, catalyzing biogeochemical reactions driving global nutrient cycles. However, unlike for plants and animals, microbial diversity is not on the biodiversity-conservation agenda. The latter, however, would imply that microbial diversity is not under any threat by anthropogenic disturbance or climate change. This maybe a misconception caused by the rudimentary knowledge we have concerning microbial diversity and its role in ecosystem functioning. This perspective paper identifies major areas with knowledge gaps within the field of environmental microbiology that preclude a comprehension of microbial ecosystems on the level we have for plants and animals. Opportunities and challenges are pointed out to open the microbial black box and to go from descriptive to predictive microbial ecology.

  4. The microbial nature of laminated limestones: Lessons from the Upper Aptian, Araripe Basin, Brazil

    Science.gov (United States)

    Catto, Bruno; Jahnert, Ricardo Jorge; Warren, Lucas Verissimo; Varejao, Filipe Giovanini; Assine, Mario Luis

    2016-07-01

    The Araripe Basin, located in northeastern Brazil, originated during the Gondwana continental break-up responsible for the opening of the South Atlantic during the Early Cretaceous. In the Araripe Basin, the post-rift Aptian sequence corresponds to the Santana Group, which is composed, in upward succession, of mostly clastic continental and rare carbonate layers of the Barbalha, Crato, Ipubi and Romualdo Formations. The laminated limestones of the Crato Formation were deposited in a lacustrine environment preceding the deposition of the Ipubi Formation evaporites. They are age-equivalent to the limestones of the pre-salt interval of the east coast of Brazil, which contains large petroleum reserves. The excellent preservation of its macrofossils has made the Crato Formation known worldwide as a Fossil Lagerstätte. The limestones are macroscopically homogeneous, and their deposition has been previously attributed to chemical precipitation. Although the carbonate laminites are macroscopically undifferentiated, mineralogical variations, microscopic texture and distinctive biotic aspects supported the characterization of four microfacies: planar laminated, crustiform, nodular and rhythmic. The microfacies analysis indicated a strong and pervasive biological activity in the Crato limestone morphogenesis. Organominerals precipitated by the metabolic action of cyanobacteria and/or sulfate-reducing bacteria and methanogenic-oxidizing archea are represented by calcite and pyrite. Calcified coccoid and filaments are common, furthermore, the presence of calcified biofilms composed of exopolymeric substances (EPS) is ubiquitous. The presence of amorphous organic matter (AOM) and gypsum, particularly in the rhythmic microfacies, indicates anoxic/dysoxic conditions and stressful environments during periods of drought and low lake levels which favored the development and preservation of microbial biofilms. Phytoclasts and miospores when present in the succession indicate an

  5. Key Concepts in Microbial Oceanography

    Science.gov (United States)

    Bruno, B. C.; Achilles, K.; Walker, G.; Weersing, K.; Team, A

    2008-12-01

    The Center for Microbial Oceanography: Research and Education (C-MORE) is a multi-institution Science and Technology Center, established by the National Science Foundation in 2006. C-MORE's research mission is to facilitate a more comprehensive understanding of the diverse assemblages of microorganisms in the sea, ranging from the genetic basis of marine microbial biogeochemistry including the metabolic regulation and environmental controls of gene expression, to the processes that underpin the fluxes of carbon, related bioelements, and energy in the marine environment. The C-MORE education and outreach program is focused on increasing scientific literacy in microbial oceanography among students, educators, and the general public. A first step toward this goal is defining the key concepts that constitute microbial oceanography. After lengthy discussions with scientists and educators, both within and outside C-MORE, we have arrived at six key concepts: 1) Marine microbes are very small and have been around for a long time; 2) Life on Earth could not exist without microbes; 3) Most marine microbes are beneficial; 4) Microbes are everywhere: they are extremely abundant and diverse; 5) Microbes significantly impact our global climate; and 6) There are new discoveries every day in the field of microbial oceanography. A C-MORE-produced brochure on these six key concepts will be distributed at the meeting. Advanced copies may be requested by email or downloaded from the C-MORE web site(http://cmore.soest.hawaii.edu/downloads/MO_key_concepts_hi-res.pdf). This brochure also includes information on career pathways in microbial oceanography, with the aim of broadening participation in the field. C-MORE is eager to work in partnership to incorporate these key concepts into other science literacy publications, particularly those involving ocean and climate literacy. We thank the following contributors and reviewers: P Chisholm, A Dolberry, and A Thompson (MIT); N Lawrence

  6. Enhancing microbial production of biofuels by expanding microbial metabolic pathways.

    Science.gov (United States)

    Yu, Ping; Chen, Xingge; Li, Peng

    2017-09-01

    Fatty acid, isoprenoid, and alcohol pathways have been successfully engineered to produce biofuels. By introducing three genes, atfA, adhE, and pdc, into Escherichia coli to expand fatty acid pathway, up to 1.28 g/L of fatty acid ethyl esters can be achieved. The isoprenoid pathway can be expanded to produce bisabolene with a high titer of 900 mg/L in Saccharomyces cerevisiae. Short- and long-chain alcohols can also be effectively biosynthesized by extending the carbon chain of ketoacids with an engineered "+1" alcohol pathway. Thus, it can be concluded that expanding microbial metabolic pathways has enormous potential for enhancing microbial production of biofuels for future industrial applications. However, some major challenges for microbial production of biofuels should be overcome to compete with traditional fossil fuels: lowering production costs, reducing the time required to construct genetic elements and to increase their predictability and reliability, and creating reusable parts with useful and predictable behavior. To address these challenges, several aspects should be further considered in future: mining and transformation of genetic elements related to metabolic pathways, assembling biofuel elements and coordinating their functions, enhancing the tolerance of host cells to biofuels, and creating modular subpathways that can be easily interconnected. © 2016 International Union of Biochemistry and Molecular Biology, Inc.

  7. Fra bog til film

    DEFF Research Database (Denmark)

    Schepelern, Peter

    2010-01-01

    Efter en historisk oversigt over samspillet mellem film og litteratur i dansk film, opstilles en råkke begreber, som filmatiseringer kan analyseres ud fra. Der ses pa det litteråre vårks status — evt. som klassiker eller bestseller. Der ses pa de centrale filmatiseringsproblemer, forhold som pråger...... adaptionsprocessen fra bog til film. De kan opdeles dels i forhold, der udspringer af filmsprogets specifikke sys- tem, dels forhold, der udspringer af filmens status som massemedium. Den färste kategori er pråget af, at filmsproget generelt fremstiller handling snarere end refleksion, noget konkret snarere end...... noget abstrakt, en scene snarere end et resume og det ydre snarere det indre. Den anden kategori kan forklare filmens tilbäjelighed til åndring af forlågget, til forkortelse, forenkling og modernisering. Eksemplerne er en råkke centrale danske film/romaner...

  8. Photographic Film Image Enhancement

    Science.gov (United States)

    1975-01-01

    A series of experiments were undertaken to assess the feasibility of defogging color film by the techniques of Optical Spatial Filtering. A coherent optical processor was built using red, blue, and green laser light input and specially designed Fouri...

  9. Thin film device applications

    CERN Document Server

    Kaur, Inderjeet

    1983-01-01

    Two-dimensional materials created ab initio by the process of condensation of atoms, molecules, or ions, called thin films, have unique properties significantly different from the corresponding bulk materials as a result of their physical dimensions, geometry, nonequilibrium microstructure, and metallurgy. Further, these characteristic features of thin films can be drasti­ cally modified and tailored to obtain the desired and required physical characteristics. These features form the basis of development of a host of extraordinary active and passive thin film device applications in the last two decades. On the one extreme, these applications are in the submicron dimensions in such areas as very large scale integration (VLSI), Josephson junction quantum interference devices, magnetic bubbles, and integrated optics. On the other extreme, large-area thin films are being used as selective coatings for solar thermal conversion, solar cells for photovoltaic conver­ sion, and protection and passivating layers. Ind...

  10. Nanodiffusion in electrocatalytic films

    Science.gov (United States)

    Costentin, Cyrille; di Giovanni, Carlo; Giraud, Marion; Savéant, Jean-Michel; Tard, Cédric

    2017-10-01

    In the active interest aroused by electrochemical reactions' catalysis, related to modern energy challenges, films deposited on electrodes are often preferred to homogeneous catalysts. A particularly promising variety of such films, in terms of efficiency and selectivity, is offered by sprinkling catalytic nanoparticles onto a conductive network. Coupled with the catalytic reaction, the competitive occurrence of various modes of substrate diffusion--diffusion toward nanoparticles (`nanodiffusion') against film linear diffusion and solution linear diffusion--is analysed theoretically. It is governed by a dimensionless parameter that contains all the experimental factors, thus allowing one to single out the conditions in which nanodiffusion is the dominant mode of mass transport. These theoretical predictions are illustrated experimentally by proton reduction on a mixture of platinum nanoparticles and carbon dispersed in a Nafion film deposited on a glassy carbon electrode. The density of nanoparticles and the scan rate are used as experimental variables to test the theory.

  11. Film: The Conversation

    National Research Council Canada - National Science Library

    Hillis, Aaron

    2009-01-01

    In an interview, director Francis Ford Coppola comments on presenting "Tetro" at the 2009 Cannes Film Festival in France, shooting the movie in high definition, his decision to distribute it himself...

  12. Musical and film time

    National Research Council Canada - National Science Library

    Kulezic-Wilson, Danijela

    2008-01-01

    Comparative analysis of linear, non-linear and multiple temporal dimensions in music and film reveals that the understanding and utilisation of time in these two arts reflect not only the aesthetic...

  13. Peel testing metalized films

    Science.gov (United States)

    Bivins, L.; Smith, T.

    1980-01-01

    Flimsy ultrathin sheets are mounted on glass for peel-strength measurements. Technique makes it easier to perform peel tests on metalized plastic films. Technique was developed for determining peel strength of thin (1,000 A) layers of aluminum on Kapton film. Previously, material has been difficult to test because it is flimsy and tends to curl up and blow away at slightest disturbance. Procedure can be used to measure effects on metalization bond strength of handling, humidity, sunlight, and heat.

  14. Min Morfars Film

    DEFF Research Database (Denmark)

    Juel, Henrik

    1957-01-01

    Reflektioner over filmhistoriebegrebet og gennemgang af konkrete filmoplevelser i 1957 og i nutiden med udgangspunkt i mødet med en gammel familiefilm. Reflektioner over valg af motiver i en social- og personhistorisk dateret film.......Reflektioner over filmhistoriebegrebet og gennemgang af konkrete filmoplevelser i 1957 og i nutiden med udgangspunkt i mødet med en gammel familiefilm. Reflektioner over valg af motiver i en social- og personhistorisk dateret film....

  15. Multifunctional thin film surface

    Science.gov (United States)

    Brozik, Susan M.; Harper, Jason C.; Polsky, Ronen; Wheeler, David R.; Arango, Dulce C.; Dirk, Shawn M.

    2015-10-13

    A thin film with multiple binding functionality can be prepared on an electrode surface via consecutive electroreduction of two or more aryl-onium salts with different functional groups. This versatile and simple method for forming multifunctional surfaces provides an effective means for immobilization of diverse molecules at close proximities. The multifunctional thin film has applications in bioelectronics, molecular electronics, clinical diagnostics, and chemical and biological sensing.

  16. Sputtered Thin Film Research

    Science.gov (United States)

    1974-11-01

    and Idonllly hy block numbor) Reactive Sputtering, Heteroepitaxy, Thin Films Single Crystal Zinc Oxide, Titanium Dioxide, Aluminum Nitride, Gallium...Conditions were determined for the deposition of amorphous neodymium ultra- phosphate films. This material holds the potential for the fabrication...reaching the substrate at any time during sputtering. A 17.2 cm diameter quartz plate was covered with a thin coating of zinc sulflde and placed on

  17. Preparation and characterization of biocomposite film based on chitosan and kombucha tea as active food packaging.

    Science.gov (United States)

    Ashrafi, Azam; Jokar, Maryam; Mohammadi Nafchi, Abdorreza

    2018-03-01

    An active film composed of chitosan and kombucha tea (KT) was successfully prepared using the solvent casting technique. The effect of incorporation of KT at the levels 1%-3% w/w on the physical and functional properties of chitosan film was investigated. The antimicrobial activity of chitosan/KT film against Escherichia coli and Staphylococcus aureus was evaluated using agar diffusion test, and its antioxidant activity was determined using DPpH assay. The results revealed that incorporation of KT into chitosan films improved the water vapor permeability (from 256.7 to 132.1gcm -2 h -1 KPa -1 mm) and enhanced the antioxidant activity of the latter up to 59% DPpH scavenging activity. Moreover, the incorporation of KT into the chitosan film increased the protective effect of the film against ultra violet (UV). Fourier transform infrared spectroscopic analysis revealed the chemical interactions between chitosan and the polyphenol groups of KT. In a minced beef model, chitosan/KT film effectively served as an active packaging and extended the shelf life of the minced beef as manifested in the retardation of lipid oxidation and microbial growth from 5.36 to 2.11logcfugr -1 in 4days storage. The present work demonstrates that the chitosan/KT film not only maintains the quality of the minced beef but also, retards microbial growth significantly, extending the shelf life of the minced beef meat up to 3days; thus, chitosan/KT film is a potential material for active food packaging. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Multiresonant layered plasmonic films

    Energy Technology Data Exchange (ETDEWEB)

    DeVetter, Brent M. [Pacific Northwest National Laboratory, Richland, Washington, United States; Bernacki, Bruce E. [Pacific Northwest National Laboratory, Richland, Washington, United States; Bennett, Wendy D. [Pacific Northwest National Laboratory, Richland, Washington, United States; Schemer-Kohrn, Alan [Pacific Northwest National Laboratory, Richland, Washington, United States; Alvine, Kyle J. [Pacific Northwest National Laboratory, Richland, Washington, United States

    2017-01-01

    Multi-resonant nanoplasmonic films have numerous applications in areas such as nonlinear optics, sensing, and tamper indication. While techniques such as focused ion beam milling and electron beam lithography can produce high-quality multi-resonant films, these techniques are expensive, serial processes that are difficult to scale at the manufacturing level. Here, we present the fabrication of multi-resonant nanoplasmonic films using a layered stacking technique. Periodically-spaced gold nanocup substrates were fabricated using self-assembled polystyrene nanospheres followed by oxygen plasma etching and metal deposition via magnetron sputter coating. By adjusting etch parameters and initial nanosphere size, it was possible to achieve an optical response ranging from the visible to the near-infrared. Singly resonant, flexible films were first made by performing peel-off using an adhesive-coated polyolefin film. Through stacking layers of the nanofilm, we demonstrate fabrication of multi-resonant films at a fraction of the cost and effort as compared to top-down lithographic techniques.

  19. Recovery and purification of polysaccharides from microbial broth.

    Science.gov (United States)

    Johns, M R; Noor, E

    1991-04-01

    Current industrial practice to recover extracellular microbial polysaccharides from the broth usually requires dilution to permit cell removal followed by precipitation, typically using alcohol. This paper presents a discussion on the solvent precipitation of xanthan and the results of research performed to investigate the behaviour of xanthan solutions during membrane processing using a microporous membrane. Using crossflow microfiltration, flux rates of up to 120 L/m2h were achieved for pure xanthan solutions, with complete rejection of the polysaccharide by the membrane. The thin film model underpredicted flux for xanthan solutions. In fact, flux was independent of xanthan concentration up to 20-25 g/L, and strongly dependent on crossflow velocity. Considerable benefits in terms of purification and reduced solvent requirements can be obtained by the use of an intermediate crossflow microfiltration step during xanthan recovery.

  20. Electrolyte-Sensing Transistor Decals Enabled by Ultrathin Microbial Nanocellulose

    Science.gov (United States)

    Yuen, Jonathan D.; Walper, Scott A.; Melde, Brian J.; Daniele, Michael A.; Stenger, David A.

    2017-01-01

    We report an ultra-thin electronic decal that can simultaneously collect, transmit and interrogate a bio-fluid. The described technology effectively integrates a thin-film organic electrochemical transistor (sensing component) with an ultrathin microbial nanocellulose wicking membrane (sample handling component). As far as we are aware, OECTs have not been integrated in thin, permeable membrane substrates for epidermal electronics. The design of the biocompatible decal allows for the physical isolation of the electronics from the human body while enabling efficient bio-fluid delivery to the transistor via vertical wicking. High currents and ON-OFF ratios were achieved, with sensitivity as low as 1 mg·L-1.

  1. Microbial degradation of petroleum hydrocarbons.

    Science.gov (United States)

    Varjani, Sunita J

    2017-01-01

    Petroleum hydrocarbon pollutants are recalcitrant compounds and are classified as priority pollutants. Cleaning up of these pollutants from environment is a real world problem. Bioremediation has become a major method employed in restoration of petroleum hydrocarbon polluted environments that makes use of natural microbial biodegradation activity. Petroleum hydrocarbons utilizing microorganisms are ubiquitously distributed in environment. They naturally biodegrade pollutants and thereby remove them from the environment. Removal of petroleum hydrocarbon pollutants from environment by applying oleophilic microorganisms (individual isolate/consortium of microorganisms) is ecofriendly and economic. Microbial biodegradation of petroleum hydrocarbon pollutants employs the enzyme catalytic activities of microorganisms to enhance the rate of pollutants degradation. This article provides an overview about bioremediation for petroleum hydrocarbon pollutants. It also includes explanation about hydrocarbon metabolism in microorganisms with a special focus on new insights obtained during past couple of years. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Microbial tannases: advances and perspectives.

    Science.gov (United States)

    Aguilar, Cristóbal N; Rodríguez, Raúl; Gutiérrez-Sánchez, Gerardo; Augur, Christopher; Favela-Torres, Ernesto; Prado-Barragan, Lilia A; Ramírez-Coronel, Ascensión; Contreras-Esquivel, Juan C

    2007-08-01

    In the last years, tannase has been the subject of a lot of studies due to its commercial importance and complexity as catalytic molecule. Tannases are capable of hydrolyzing complex tannins, which represent the main chemical group of natural anti-microbials occurring in the plants. The general outline of this work includes information of the substrates, the enzyme, and the applications. This review considers in its introduction the concepts and history of tannase and explores scientific and technological aspects. The "advances" trace the route from the general, molecular, catalytic, and functional information obtained under close to optimal conditions for microbial production through purification, description of the enzyme properties, and the commercial applications to the "perspectives" including expression studies, regulation, and potential uses; aspects related to the progress in our understanding of tannin biodegradation are also included.

  3. Microbial methods of reducing technetium

    Science.gov (United States)

    Wildung, Raymond E [Richland, WA; Garland, Thomas R [Greybull, WY; Gorby, Yuri A [Richland, WA; Hess, Nancy J [Benton City, WA; Li, Shu-Mei W [Richland, WA; Plymale, Andrew E [Richland, WA

    2001-01-01

    The present invention is directed toward a method for microbial reduction of a technetium compound to form other compounds of value in medical imaging. The technetium compound is combined in a mixture with non-growing microbial cells which contain a technetium-reducing enzyme system, a stabilizing agent and an electron donor in a saline solution under anaerobic conditions. The mixture is substantially free of an inorganic technetium reducing agent and its reduction products. The resulting product is Tc of lower oxidation states, the form of which can be partially controlled by the stabilizing agent. It has been discovered that the microorganisms Shewanella alga, strain Bry and Shewanelia putrifacians, strain CN-32 contain the necessary enzyme systems for technetium reduction and can form both mono nuclear and polynuclear reduced Tc species depending on the stabilizing agent.

  4. Synthetic microbial ecosystems for biotechnology.

    Science.gov (United States)

    Pandhal, Jagroop; Noirel, Josselin

    2014-06-01

    Most highly controlled and specific applications of microorganisms in biotechnology involve pure cultures. Maintaining single strain cultures is important for industry as contaminants can reduce productivity and lead to longer "down-times" during sterilisation. However, microbes working together provide distinct advantages over pure cultures. They can undertake more metabolically complex tasks, improve efficiency and even expand applications to open systems. By combining rapidly advancing technologies with ecological theory, the use of microbial ecosystems in biotechnology will inevitably increase. This review provides insight into the use of synthetic microbial communities in biotechnology by applying the engineering paradigm of measure, model, manipulate and manufacture, and illustrate the emerging wider potential of the synthetic ecology field. Systems to improve biofuel production using microalgae are also discussed.

  5. Toward engineering synthetic microbial metabolism.

    Science.gov (United States)

    McArthur, George H; Fong, Stephen S

    2010-01-01

    The generation of well-characterized parts and the formulation of biological design principles in synthetic biology are laying the foundation for more complex and advanced microbial metabolic engineering. Improvements in de novo DNA synthesis and codon-optimization alone are already contributing to the manufacturing of pathway enzymes with improved or novel function. Further development of analytical and computer-aided design tools should accelerate the forward engineering of precisely regulated synthetic pathways by providing a standard framework for the predictable design of biological systems from well-characterized parts. In this review we discuss the current state of synthetic biology within a four-stage framework (design, modeling, synthesis, analysis) and highlight areas requiring further advancement to facilitate true engineering of synthetic microbial metabolism.

  6. Toward Engineering Synthetic Microbial Metabolism

    Directory of Open Access Journals (Sweden)

    George H. McArthur

    2010-01-01

    Full Text Available The generation of well-characterized parts and the formulation of biological design principles in synthetic biology are laying the foundation for more complex and advanced microbial metabolic engineering. Improvements in de novo DNA synthesis and codon-optimization alone are already contributing to the manufacturing of pathway enzymes with improved or novel function. Further development of analytical and computer-aided design tools should accelerate the forward engineering of precisely regulated synthetic pathways by providing a standard framework for the predictable design of biological systems from well-characterized parts. In this review we discuss the current state of synthetic biology within a four-stage framework (design, modeling, synthesis, analysis and highlight areas requiring further advancement to facilitate true engineering of synthetic microbial metabolism.

  7. Microbial siderophores: a mini review.

    Science.gov (United States)

    Saha, Ratul; Saha, Nabaneeta; Donofrio, Robert S; Bestervelt, Lorelle L

    2013-04-01

    Iron is one of the major limiting factors and essential nutrients of microbial life. Since in nature it is not readily available in the preferred form, microorganisms produce small high affinity chelating molecules called siderophores for its acquisition. Microorganisms produce a wide variety of siderophores controlled at the molecular level by different genes to accumulate, mobilize and transport iron for metabolism. Siderophores also play a critical role in the expression of virulence and development of biofilms by different microbes. Apart from maintaining microbial life, siderophores can be harnessed for the sustainability of human, animals and plants. With the advent of modern molecular tools, a major breakthrough is taking place in the understanding of the multifaceted role of siderophores in nature. This mini review is intended to provide a general overview on siderophore along with its role and applications. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Microbial Flocculant for Nature Soda

    Energy Technology Data Exchange (ETDEWEB)

    Qin, Peiyong; Zhang, Tong; Chen, Cuixian

    2004-03-31

    Microbial flocculant for nature soda has been studied. Lactobacillus TRJ21, which was able to produce an excellent biopolymer flocculant for nature soda, was obtained in our lab. The microbial flocculant was mainly produced when the bacteria laid in stationary growth phase. Fructose or glucose, as carbon sources, were more favorable for the bacterial growth and flocculant production. The bacteria was able to use ammonium sulfate or Urea as nitrogen to produce flocculant, but was not able to use peptone effectively. High C/N ratio was more favorable to Lactobacillus TRJ21 growth and flocculant production than low C/N ratio. The biopolymer flocculant was mainly composed of polysaccharide and protein with a molecular weight 1.38x106 by gel permeation chromatography. It was able to be easily purified from the culture medium by acetone. Protein in the flocculant was tested for the flocculating activity ingredient by heating the flocculant.

  9. Microbial activity at Yucca Mountain

    Energy Technology Data Exchange (ETDEWEB)

    Horn, J.M.; Meike, A.

    1995-09-25

    The U.S. Department of Energy is engaged in a suitability study for a potential geological repository at Yucca Mountain, Nevada, for the containment and storage of commercially generated spent fuel and defense high-level nuclear waste. There is growing recognition of the role that biotic factors could play in this repository, either directly through microbially induced corrosion (MIC), or indirectly by altering the chemical environment or contributing to the transport of radionuclides. As a first step toward describing and predicting these processes, a workshop was held on April 10-12, 1995, in Lafayette, California. The immediate aims of the workshop were: (1) To identify microbially related processes relevant to the design of a radioactive waste repository under conditions similar to those at Yucca Mountain. (2) To determine parameters that are critical to the evaluation of a disturbed subterranean environment. (3) To define the most effective means of investigating the factors thus identified.

  10. Theory of microbial genome evolution

    Science.gov (United States)

    Koonin, Eugene

    Bacteria and archaea have small genomes tightly packed with protein-coding genes. This compactness is commonly perceived as evidence of adaptive genome streamlining caused by strong purifying selection in large microbial populations. In such populations, even the small cost incurred by nonfunctional DNA because of extra energy and time expenditure is thought to be sufficient for this extra genetic material to be eliminated by selection. However, contrary to the predictions of this model, there exists a consistent, positive correlation between the strength of selection at the protein sequence level, measured as the ratio of nonsynonymous to synonymous substitution rates, and microbial genome size. By fitting the genome size distributions in multiple groups of prokaryotes to predictions of mathematical models of population evolution, we show that only models in which acquisition of additional genes is, on average, slightly beneficial yield a good fit to genomic data. Thus, the number of genes in prokaryotic genomes seems to reflect the equilibrium between the benefit of additional genes that diminishes as the genome grows and deletion bias. New genes acquired by microbial genomes, on average, appear to be adaptive. Evolution of bacterial and archaeal genomes involves extensive horizontal gene transfer and gene loss. Many microbes have open pangenomes, where each newly sequenced genome contains more than 10% `ORFans', genes without detectable homologues in other species. A simple, steady-state evolutionary model reveals two sharply distinct classes of microbial genes, one of which (ORFans) is characterized by effectively instantaneous gene replacement, whereas the other consists of genes with finite, distributed replacement rates. These findings imply a conservative estimate of at least a billion distinct genes in the prokaryotic genomic universe.

  11. Microbial Keratitis After Penetrating Keratoplasty.

    Science.gov (United States)

    Sun, Jen-Pin; Chen, Wei-Li; Huang, Jehn-Yu; Hou, Yu-Chih; Wang, I-Jong; Hu, Fung-Rong

    2017-06-01

    To report the incidence, microbiological profile, graft survival, and determining factors of microbial keratitis after penetrating keratoplasty (PK). Observational case series. The study involved 51 patients (52 eyes) who were treated at a single tertiary referral center during a 10-year period. Retrospective chart review included medical records of all patients diagnosed with microbial keratitis after penetrating keratoplasty at the National Taiwan University Hospital between January 2000 and December 2009. The main outcome measures were incidence of graft infection, microbial profile, and graft survival status. There were 871 PKs performed and 67 episodes in 52 eyes of culture-positive microbial keratitis during the study period. There were 32 infectious episodes (47.8%) in the first year post-PK and 35 episodes (52.2%) after the first year post-PK. Forty-four gram-positive bacterial isolates (57.9%), 17 gram-negative bacterial isolates (22.4%), and 15 fungal isolates (19.7%) were found. Twenty-three (34.3%) grafts remained clear after the infection episode with a mean follow-up of 1127 days (range, 25-3962 days). There was no difference in graft survival rate regarding the original indication of PK or offending pathogen. Suture-related infection was associated with decreased risk of graft failure (P = .02), while the factor associated with increased risk of graft failure was usage of antiglaucoma agents (P = .01). Infectious keratitis after penetrating keratoplasty leads to a high graft failure rate. Such complications can occur before or after the first year post-PK. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Biofilm: A dental microbial infection

    OpenAIRE

    Saini, Rajiv; Saini, Santosh; Sharma, Sugandha

    2011-01-01

    Recent advances in research technology have allowed researchers to study bacteria in their natural environment. Dental biofilm forms via an ordered sequence of events, resulting in structured and functionally organized species rich microbial community and modern molecular biological techniques have identified about 1000 different bacterial species in the dental biofilm, twice as many as can be cultured. Sites for biofilm formation include all kinds of surfaces: natural materials above and bel...

  13. Molecular indicators for palaeoenvironmental change in a Messinian evaporitic sequence (Vena del Gesso, Italy). II: High-resolution variations in abundances and 13C contents of free and sulphur-bound carbon skeletons in a single marl bed

    Science.gov (United States)

    Kenig, F.; Damste, J. S.; Frewin, N. L.; Hayes, J. M.; De Leeuw, J. W.

    1995-01-01

    The extractable organic matter of 10 immature samples from a marl bed of one evaporitic cycle of the Vena del Gesso sediments (Gessoso-solfifera Fm., Messinian, Italy) was analyzed quantitatively for free hydrocarbons and organic sulphur compounds. Nickel boride was used as a desulphurizing agent to recover sulphur-bound lipids from the polar and asphaltene fractions. Carbon isotopic compositions (delta vs PDB) of free hydrocarbons and of S-bound hydrocarbons were also measured. Relationships between these carbon skeletons, precursor biolipids, and the organisms producing them could then be examined. Concentrations of S-bound lipids and free hydrocarbons and their delta values were plotted vs depth in the marl bed and the profiles were interpreted in terms of variations in source organisms, 13 C contents of the carbon source, and environmentally induced changes in isotopic fractionation. The overall range of delta values measured was 24.7%, from -11.6% for a component derived from green sulphur bacteria (Chlorobiaceae) to -36.3% for a lipid derived from purple sulphur bacteria (Chromatiaceae). Deconvolution of mixtures of components deriving from multiple sources (green and purple sulphur bacteria, coccolithophorids, microalgae and higher plants) was sometimes possible because both quantitative and isotopic data were available and because either the free or S-bound pool sometimes appeared to contain material from a single source. Several free n-alkanes and S-bound lipids appeared to be specific products of upper-water-column primary producers (i.e. algae and cyanobacteria). Others derived from anaerobic photoautotrophs and from heterotrophic protozoa (ciliates), which apparently fed partly on Chlorobiaceae. Four groups of n-alkanes produced by algae or cyanobacteria were also recognized based on systematic variations of abundance and isotopic composition with depth. For hydrocarbons probably derived from microalgae, isotopic variations are well correlated with

  14. Microbial terroir for wine grapes

    Energy Technology Data Exchange (ETDEWEB)

    Gilbert, J. A.; van der Lelie, D.; Zarraonaindia, I.

    2013-12-05

    The viticulture industry has been selectively growing vine cultivars with different traits (grape size, shape, color, flavor, yield of fruit, and so forth) for millennia, and small variations in soil composition, water management, climate, and the aspect of vineyards have long been associated with shifts in these traits. As such, many different clonal varieties of vines exist, even within given grape varieties, such as merlot, pinot noir, and chardonnay. The commensal microbial flora that coexists with the plant may be one of the key factors that influence these traits. To date, the role of microbes has been largely ignored, outside of microbial pathogens, mainly because the technologies did not exist to allow us to look in any real depth or breadth at the community structure of the multitudes of bacterial and fungal species associated with each plant. In PNAS, Bokulich et al. (1) used next-generation sequencing of 16S rRNA and internal transcribed spacer ribosomal sequence to determine the relative abundances of bacteria and fungi, respectively, from grape must (freshly pressed grape juice, containing the skins and seeds) from plants in eight vineyards representing four of the major wine growing regions in California. The authors show that the microbiomes (bacterial and fungal taxonomic structure) associated with this early fermentation stage show defined biogeography, illustrating that different wine-growing regions maintain different microbial communities, with some influences from the grape variety and the year of production.

  15. Microbial regulation in gorgonian corals.

    Science.gov (United States)

    Hunt, Laura R; Smith, Stephanie M; Downum, Kelsey R; Mydlarz, Laura D

    2012-06-01

    Gorgonian corals possess many novel natural products that could potentially mediate coral-bacterial interactions. Since many bacteria use quorum sensing (QS) signals to facilitate colonization of host organisms, regulation of prokaryotic cell-to-cell communication may represent an important bacterial control mechanism. In the present study, we examined extracts of twelve species of Caribbean gorgonian corals, for mechanisms that regulate microbial colonization, such as antibacterial activity and QS regulatory activity. Ethanol extracts of gorgonians collected from Puerto Rico and the Florida Keys showed a range of both antibacterial and QS activities using a specific Pseudomonas aeruginosa QS reporter, sensitive to long chain AHLs and a short chain N-acylhomoserine lactones (AHL) biosensor, Chromobacterium violaceium. Overall, the gorgonian corals had higher antimicrobial activity against non-marine strains when compared to marine strains. Pseudopterogorgia americana, Pseusopterogorgia acerosa, and Pseudoplexuara flexuosa had the highest QS inhibitory effect. Interestingly, Pseudoplexuara porosa extracts stimulated QS activity with a striking 17-fold increase in signal. The stimulation of QS by P. porosa or other elements of the holobiont may encourage colonization or recruitment of specific microbial species. Overall, these results suggest the presence of novel stimulatory QS, inhibitory QS and bactericidal compounds in gorgonian corals. A better understanding of these compounds may reveal insight into coral-microbial ecology and whether a therapeutic potential exists.

  16. Microbial consortia at steady supply

    Science.gov (United States)

    Taillefumier, Thibaud; Posfai, Anna; Meir, Yigal; Wingreen, Ned S

    2017-01-01

    Metagenomics has revealed hundreds of species in almost all microbiota. In a few well-studied cases, microbial communities have been observed to coordinate their metabolic fluxes. In principle, microbes can divide tasks to reap the benefits of specialization, as in human economies. However, the benefits and stability of an economy of microbial specialists are far from obvious. Here, we physically model the population dynamics of microbes that compete for steadily supplied resources. Importantly, we explicitly model the metabolic fluxes yielding cellular biomass production under the constraint of a limited enzyme budget. We find that population dynamics generally leads to the coexistence of different metabolic types. We establish that these microbial consortia act as cartels, whereby population dynamics pins down resource concentrations at values for which no other strategy can invade. Finally, we propose that at steady supply, cartels of competing strategies automatically yield maximum biomass, thereby achieving a collective optimum. DOI: http://dx.doi.org/10.7554/eLife.22644.001 PMID:28473032

  17. Flow injection microbial trichloroethylene sensor.

    Science.gov (United States)

    Han, Tae-Sung; Sasaki, Satoshi; Yano, Kazuyoshi; Ikebukuro, Kazunori; Kitayama, Atsushi; Nagamune, Teruyuki; Karube, Isao

    2002-05-16

    A flow type microbial biosensor for direct measurement of trichloroethylene (TCE) was developed. The unique features of this novel microbial sensor were the use of the TCE degrading bacterium Pseudomonas aeruginosa JI104, the electrical detection of the chloride ion released by microbial degradation, and flow cell made of glass. Glass cell was used in order to suppress adsorption of TCE and made a closed reaction cell. Vaporization of TCE during the measurement was prevented using closed flow cell. The performance of the sensor was evaluated from following aspects; such as pH of the carrier solution, amount of the immobilized microbe, flow rate and injection volume. The sensor signals were linearly proportional to the concentration of TCE in the range from 0.03 to 2 mgl(-1), which is suitable for the determination of suspected samples to be drinkable water or not. The sensor performance was checked on the real sample, and this system showed good response in ground water, indicating its applicability for the on line monitoring at TCE contaminated areas or hazardous sites.

  18. Simplifying Microbial Electrosynthesis Reactor Design

    Directory of Open Access Journals (Sweden)

    Cloelle G.S. Giddings

    2015-05-01

    Full Text Available Microbial electrosynthesis, an artificial form of photosynthesis, can efficiently convert carbon dioxide into organic commodities; however, this process has only previously been demonstrated in reactors that have features likely to be a barrier to scale-up. Therefore, the possibility of simplifying reactor design by both eliminating potentiostatic control of the cathode and removing the membrane separating the anode and cathode was investigated with biofilms of Sporomusa ovata, which reduces carbon dioxide to acetate. In traditional ‘H-cell’ reactors, where the anode and cathode chambers were separated with a proton-selective membrane, the rates and columbic efficiencies of microbial electrosynthesis remained high when electron delivery at the cathode was powered with a direct current power source rather than with a poteniostat-poised cathode utilized in previous studies. A membrane-less reactor with a direct-current power source with the cathode and anode positioned to avoid oxygen exposure at the cathode, retained high rates of acetate production as well as high columbic and energetic efficiencies. The finding that microbial electrosynthesis is feasible without a membrane separating the anode from the cathode, coupled with a direct current power source supplying the energy for electron delivery, is expected to greatly simplify future reactor design and lower construction costs.

  19. In-Flight Microbial Monitor

    Science.gov (United States)

    Zeitlin, Nancy; Mullenix, Pamela; Wheeler, Raymond M.; Ruby, Anna Maria

    2015-01-01

    Previous research has shown that potential human pathogens have been detected on the International Space Station (ISS). New microorganisms are introduced with every exchange of crew and cargo. Microorganisms introduced to the ISS are readily transferred between crew and subsystems (i.e., ECLSS, environmental control and life support systems). Current microbial characterization methods require a culture-based enrichment of microorganisms and at least a 48-hour incubation time. This increases the microbial load while detecting only a limited number of microorganisms. The culture-based method detects approximately 1-10% of the total organisms present and provides no identification. To identify and enumerate ISS samples requires that the microbes be returned to Earth for complete analysis. Therefore, a more expedient, low-cost, inflight method of microbial detection, identification, and enumeration is needed. The RAZOR EX, a ruggedized, commercial off the shelf, real-time PCR field instrument was tested for its ability to detect microorganisms at low concentrations within one hour. Escherichia coli, Salmonella enterica Typhimurium, and Pseudomonas aeruginosa were detected at low levels using real-time DNA amplification. Total heterotrophic counts could also be detected using a 16S gene marker that can identify up to 98% of all bacteria. To reflect viable cells found in the samples, RNA was also detectable using a modified, single-step reverse transcription reaction.

  20. Dynamic processes in soap films.

    Science.gov (United States)

    Mysels, K J

    1968-07-01

    Some relations between the two main types of thin liquid films, the water-in-air "soap" films and the invert oil-in-water "lipid" films, are outlined, and several dynamic aspects of film behavior are illustrated and briefly reviewed with reference to more complete treatments. These dynamic processes are important in both types of films, but are easier to study in soap films. The topics include the difference between rigid and mobile films and their interconversion; the origin and measurement of film elasticity; the effect of rate of formation upon film thickness, and the evidence against the existence of thick rigid water layers at the surface; and the kinetics of drainage and the role played in it by viscous flow, marginal regeneration, and intermolecular forces.

  1. Physicochemical properties and bioactivity of nisin-containing cross-linked hydroxypropylmethylcellulose films.

    Science.gov (United States)

    Sebti, Issam; Delves-Broughton, John; Coma, Véronique

    2003-10-22

    Cross-linked hydroxypropylmethylcellulose (HPMC) cast films with citric acid as polycarboxylic cross-linker were elaborated to study the effect of cross-linking level on various properties. Increased amounts of cross-linking agent were not connected to statistically different tensile strength and Young's modulus. Whatever the cross-linking level of the film was, the ultimate elongation parameter decreased by approximately 60% compared to the HMPC control film. Moisture sorption isotherms and water contact angle meter showed that the effect of cross-linking degree tends to reduce the hygroscopic and hydrophilic characteristics of films. In addition, to control bacteria growth on food surfaces, the antimicrobial activity of both 98% cross-linked HPMC-nisin and control HPMC-nisin films was tested on Micrococcus luteus. Despite the incorporation of a significant content of nisin, cross-linked HPMC-nisin films were completely inactive on the microbial strain compared to the HPMC-nisin control films. Cross-linking conditions likely either denatured the nisin or irreversibly bound nisin to the cross-linked HPMC. However, nisin adsorbed into films made from previously cross-linked HPMC maintained its activity.

  2. WATER SORPTION PROPERTIES AND ANTIMICROBIAL ACTION OF ZINC OXIDE NANO PARTICLES LOADED SAGO STARCH FILM

    Directory of Open Access Journals (Sweden)

    Sunil Bajpai

    2013-02-01

    Full Text Available In this work, sago starch based films have been loaded with ZnO nanoparticles prepared insitu via using an unique equilibration-cum-hydrothermal approach. The films have been characterized by XRD, DSC,SPR ,FTIR and SEM analysis. The moisture absorption behavior of plain and ZnO nanoparticles loaded films have been studied at 23, 31 and 37o C.The equilibrium moisture uptake data was found to fit well on GAB isotherm model and the monolayer sorption capacity Mo for the plain and ZnO nanoparticles loaded films was 0.089, 0.039 ,0.021 g/g and 0.042, 0.012, 0.007 g/g at 23,31 and 37 oC respectively. Moreover, the water vapor transmission rates (WVTR for plain and ZnO nanoparticles loaded films at 23,31,37 oC were 11.19x10-4, 48.9x10-4, 62.1x10-4 and 3.73 x10-4, 6.21x10-4, 24.8x10-4 respectively. These films have shown excellent antibacterial action against model bacteria E.coli when investigated qualitatively by zone inhibition method. Films exhibit great potential to be used as packaging films to protect food stuff against microbial contaminents.

  3. Impact of Microbial Growth on Subsurface Perfluoroalkyl Acid Transport

    Science.gov (United States)

    Weathers, T. S.; Higgins, C. P.; Sharp, J.

    2014-12-01

    The fate and transport of poly and perfluoroalkyl substances (PFASs) in the presence of active microbial communities has not been widely investigated. These emerging contaminants are commonly utilized in aqueous film-forming foams (AFFF) and have often been detected in groundwater. This study explores the transport of a suite of perfluorocarboxylic acids and perfluoroalkylsulfonates, including perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), in microbially active settings. Single point organic carbon normalized sorption coefficients derived by exposing inactive cellular material to PFASs result in more than an order of magnitude increase in sorption compared to soil organic carbon sorption coefficients found in literature. For example, the sorption coefficients for PFOS are 4.05±0.07 L/kg and 2.80±0.08 L/kg for cellular organic carbon and soil organic carbon respectively. This increase in sorption, coupled with enhanced extracellular polymeric substance production observed during growth of a common hydrocarbon degrading soil microbe exposed to source-level concentrations of PFASs (10 mg/L of 11 analytes, 110 mg/L total) may result in PFAS retardation in situ. To address the upscaling of this phenomenon, flow-through columns packed with low-organic carbon sediment and biostimulated with 10 mg/L glucose were exposed to PFAS concentrations from 15 μg/L to 10 mg/L of each 11 analytes. Breakthrough and tailing of each analyte was measured and modeled with Hydrus-1D to explore sorption coefficients over time for microbially active columns.

  4. Cold Oxygen Plasma Treatments for the Improvement of the Physicochemical and Biodegradable Properties of Polylactic Acid Films for Food Packaging.

    Science.gov (United States)

    Song, Ah Young; Oh, Yoon Ah; Roh, Si Hyeon; Kim, Ji Hyeon; Min, Sea C

    2016-01-01

    The effects of cold plasma (CP) treatment on the physicochemical and biodegradable properties of polylactic acid (PLA) films were studied. The PLA films were exposed to CP for 40 min at 900 W and 667 Pa using oxygen as the plasma-forming gas. The tensile, optical, and dynamic mechanical thermal properties, surface morphology, printability, water contact angle, chemical structure, weight change, and biodegradability properties of the films were evaluated during storage for up to 56 d. The tensile and optical properties of the PLA films were not significantly affected by CP treatment (CPT; P > 0.05). The surface roughness and water contact angle of PLA films increased by CPT and further increased during storage for 56 d. The printability of the PLA films increased following CPT and remained stable throughout the storage period. CP-induced hydrophilicity was also sustained during the storage period. The PLA films lost 1.9% of their weight after CPT, but recovered 99.5% of this loss after 14 d in storage. Photodegradation, thermal, and microbial biodegradable properties of the films were significantly improved by CPT (P < 0.05). Accelerated biodegradation of CP-treated PLA sachets with and without cheese was observed in compost. These results demonstrate the potential of CPT for modifying the stiffness, water contact angle, and chemical structure of PLA films and improving the printability and biodegradability of the films for food packaging. © 2015 Institute of Food Technologists®

  5. Biomarkers: d13C and d15N Distribution Tightly Coupled to Nutrient Dynamics and Viral Lysing in a Microbial Mat From Death Valley, California

    Science.gov (United States)

    Hewson, I.; Archer, R.; Mahaffey, C.; Scott, J.; Tsapin, A.

    2002-12-01

    downward organic C (polysaccaride exudates) transport within the mat. Subsequent accumulation of d13C as well as heavier d15N in deeper sediment(denitrification)horizons elucidates tight nutrient coupling between evaporite substrate, nitrogen fixing primary producers and downcore zones of active denitrification and sulphate reduction. Discrepencies between d13C of ancient stromatolites (in line with C-3 photosynthetic pathways) and modern analogues (Badwater, CA) suggest a migration of microbial mats towards more extreme environments through time. A methodology for isotopically testing environmental and physiological responses in the geological record is presented here.

  6. Effect of plant essential oils on antimicrobial and physical properties of apple-puree, edible films and coatings

    Science.gov (United States)

    The use of edible films as carriers of antimicrobial plant essential oils and other phytochemicals constitutes an approach for external protection of food systems to reduce surface microbial populations and to enhance oxygen-barrier properties, thus enhancing food safety as well as shelf life. The o...

  7. Specialized microbial databases for inductive exploration of microbial genome sequences

    Directory of Open Access Journals (Sweden)

    Cabau Cédric

    2005-02-01

    Full Text Available Abstract Background The enormous amount of genome sequence data asks for user-oriented databases to manage sequences and annotations. Queries must include search tools permitting function identification through exploration of related objects. Methods The GenoList package for collecting and mining microbial genome databases has been rewritten using MySQL as the database management system. Functions that were not available in MySQL, such as nested subquery, have been implemented. Results Inductive reasoning in the study of genomes starts from "islands of knowledge", centered around genes with some known background. With this concept of "neighborhood" in mind, a modified version of the GenoList structure has been used for organizing sequence data from prokaryotic genomes of particular interest in China. GenoChore http://bioinfo.hku.hk/genochore.html, a set of 17 specialized end-user-oriented microbial databases (including one instance of Microsporidia, Encephalitozoon cuniculi, a member of Eukarya has been made publicly available. These databases allow the user to browse genome sequence and annotation data using standard queries. In addition they provide a weekly update of searches against the world-wide protein sequences data libraries, allowing one to monitor annotation updates on genes of interest. Finally, they allow users to search for patterns in DNA or protein sequences, taking into account a clustering of genes into formal operons, as well as providing extra facilities to query sequences using predefined sequence patterns. Conclusion This growing set of specialized microbial databases organize data created by the first Chinese bacterial genome programs (ThermaList, Thermoanaerobacter tencongensis, LeptoList, with two different genomes of Leptospira interrogans and SepiList, Staphylococcus epidermidis associated to related organisms for comparison.

  8. MAPLE fabrication of thin films based on kanamycin functionalized magnetite nanoparticles with anti-pathogenic properties

    Science.gov (United States)

    Grumezescu, Valentina; Andronescu, Ecaterina; Holban, Alina Maria; Mogoantă, Laurenţiu; Mogoşanu, George Dan; Grumezescu, Alexandru Mihai; Stănculescu, Anca; Socol, Gabriel; Iordache, Florin; Maniu, Horia; Chifiriuc, Mariana Carmen

    2015-05-01

    In this study we aimed to evaluate the biocompatibility and antimicrobial activity of kanamycin functionalized 5 nm-magnetite (Fe3O4@KAN) nanoparticles thin films deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. A laser deposition regime was established in order to stoichiometrically transfer Fe3O4@KAN thin films on silicone and glass substrates. Morphological and physico-chemical properties of powders and coatings were characterized by XRD, TEM, SEM, AFM and IR microscopy (IRM). Our nanostructured thin films have proved efficiency in the prevention of microbial adhesion and mature biofilms development as a result of antibiotic release in its active form. Furthermore, kanamycin functionalized nanostructures exhibit a good biocompatibility, both in vivo and in vitro, demonstrating their potential for implants application. This is the first study reporting the assessment of the in vivo biocompatibility of a magnetite-antimicrobial thin films produced by MAPLE technique.

  9. Epitaxial thin films

    Science.gov (United States)

    Hunt, Andrew Tye; Deshpande, Girish; Lin, Wen-Yi; Jan, Tzyy-Jiuan

    2006-04-25

    Epitatial thin films for use as buffer layers for high temperature superconductors, electrolytes in solid oxide fuel cells (SOFC), gas separation membranes or dielectric material in electronic devices, are disclosed. By using CCVD, CACVD or any other suitable deposition process, epitaxial films having pore-free, ideal grain boundaries, and dense structure can be formed. Several different types of materials are disclosed for use as buffer layers in high temperature superconductors. In addition, the use of epitaxial thin films for electrolytes and electrode formation in SOFCs results in densification for pore-free and ideal gain boundary/interface microstructure. Gas separation membranes for the production of oxygen and hydrogen are also disclosed. These semipermeable membranes are formed by high-quality, dense, gas-tight, pinhole free sub-micro scale layers of mixed-conducting oxides on porous ceramic substrates. Epitaxial thin films as dielectric material in capacitors are also taught herein. Capacitors are utilized according to their capacitance values which are dependent on their physical structure and dielectric permittivity. The epitaxial thin films of the current invention form low-loss dielectric layers with extremely high permittivity. This high permittivity allows for the formation of capacitors that can have their capacitance adjusted by applying a DC bias between their electrodes.

  10. Microbial diversity and the genetic nature of microbial species.

    Science.gov (United States)

    Achtman, Mark; Wagner, Michael

    2008-06-01

    The earth contains a huge number of largely uncharacterized Bacteria and Archaea. Microbiologists are struggling to summarize their genetic diversity and classify them, which has resulted in heated debates on methods for defining species, mechanisms that lead to speciation and whether microbial species even exist. This Review proposes that decisions on the existence of species and methods to define them should be guided by a method-free species concept that is based on cohesive evolutionary forces. It summarizes current approaches to defining species and the problems of these approaches, and presents selected examples of the population genetic patterns at and below the species level.

  11. Dewetting of Thin Polymer Films

    Science.gov (United States)

    Dixit, P. S.; Sorensen, J. L.; Kent, M.; Jeon, H. S.

    2001-03-01

    DEWETTING OF THIN POLYMER FILMS P. S. Dixit,(1) J. L. Sorensen,(2) M. Kent,(2) H. S. Jeon*(1) (1) Department of Petroleum and Chemical Engineering, New Mexico Institute of Mining and Technology, 801 Leroy Place, Socorro, NM 87801, jeon@nmt.edu (2) Department 1832, Sandia National Laboratories, Albuquerque, NM. Dewetting of thin polymer films is of technological importance for a variety of applications such as protective coatings, dielectric layers, and adhesives. Stable and smooth films are required for the above applications. Above the glass transition temperature (Tg) the instability of polymer thin films on a nonwettable substrate can be occurred. The dewetting mechanism and structure of polypropylene (Tg = -20 ^circC) and polystyrene (Tg = 100 ^circC) thin films is investigated as a function of film thickness (25 Åh < 250 Åand quenching temperature. Contact angle measurements are used in conjunction with optical microscope to check the surface homogeneity of the films. Uniform thin films are prepared by spin casting the polymer solutions onto silicon substrates with different contact angles. We found that the stable and unstable regions of the thin films as a function of the film thickness and quenching temperature, and then constructed a stability diagram for the dewetting of thin polymer films. We also found that the dewetting patterns of the thin films are affected substantially by the changes of film thickness and quenching temperature.

  12. Film beyond boundaries: film, migrant narratives and other media

    OpenAIRE

    Anelise Reich Corseuil

    2006-01-01

    The articles here presented are representative of the debates about the various transformational aspects of film studies, fostering the discussion about the transformations and interactions between national and international narrative forms, the interrelations between film and literature, and film with other media. The critical perspectives here presented range from an emphasis on cultural materialism, dialogism, reception theory, deconstructionism, narrative studies to film aesthetics or fil...

  13. Gammel Sherlock Holmes-film fundet - igen

    DEFF Research Database (Denmark)

    Lauridsen, Palle Schantz

    2017-01-01

    Om genfunden af en forsvundet Sherlock Holmes-film fra 1911, produceret af Nordisk Films Kompagni......Om genfunden af en forsvundet Sherlock Holmes-film fra 1911, produceret af Nordisk Films Kompagni...

  14. A microbial perspective of human developmental biology.

    Science.gov (United States)

    Charbonneau, Mark R; Blanton, Laura V; DiGiulio, Daniel B; Relman, David A; Lebrilla, Carlito B; Mills, David A; Gordon, Jeffrey I

    2016-07-07

    When most people think of human development, they tend to consider only human cells and organs. Yet there is another facet that involves human-associated microbial communities. A microbial perspective of human development provides opportunities to refine our definitions of healthy prenatal and postnatal growth and to develop innovative strategies for disease prevention and treatment. Given the dramatic changes in lifestyles and disease patterns that are occurring with globalization, we issue a call for the establishment of 'human microbial observatories' designed to examine microbial community development in birth cohorts representing populations with diverse anthropological characteristics, including those undergoing rapid change.

  15. Microbial fructosyltransferases and the role of fructans

    National Research Council Canada - National Science Library

    Velázquez-Hernández, M L; Baizabal-Aguirre, V M; Bravo-Patiño, A; Cajero-Juárez, M; Chávez-Moctezuma, M P; Valdez-Alarcón, J J

    2009-01-01

    ... (levan, inulin and fructo-oligosaccharide) biosynthesis. Structurally, microbial fructosyltransferase proteins share the catalytic domain of glycoside hydrolases 68 family and are grouped in seven phylogenetically related clusters...

  16. Microbial diversity supporting dark fermentation of waste.

    Science.gov (United States)

    Jobard, Marlène; Pessiot, Jérémy; Nouaille, Régis; Sime-Ngando, Télesphore

    2014-11-01

    Microbial diversity is essential for human well-being and ecosystem services. Use of microorganisms in biomolecule production is common, but involves single-strain cultures. Microbial consortia provide advantages in the process of degrading organic waste to yield biomolecules of biotechnological interest. Microbial diversity in consortia can be an asset in the context of bioenergy and chemical production, which are key concerns for global energy demands. Improving knowledge of microbial consortia will therefore be important for biotechnology. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Microbial Degradation of a Recalcitrant Pesticide: Chlordecone

    National Research Council Canada - National Science Library

    Chaussonnerie, Sébastien; Saaidi, Pierre-Loïc; Ugarte, Edgardo; Barbance, Agnès; Fossey, Aurélie; Barbe, Valérie; Gyapay, Gabor; Brüls, Thomas; Chevallier, Marion; Couturat, Loïc; Fouteau, Stéphanie; Muselet, Delphine; Pateau, Emilie; Cohen, Georges N; Fonknechten, Nuria; Weissenbach, Jean; Le Paslier, Denis

    2016-01-01

    .... In order to investigate the biodegradability of chlordecone, microbial enrichment cultures from soils contaminated by chlordecone or other organochlorines and from sludge of a wastewater treatment...

  18. Film Propaganda: Ikonografi Kekuasaan

    Directory of Open Access Journals (Sweden)

    Budi Irawanto

    2004-07-01

    Full Text Available As a modern technological invention cinema has numerous potentialities such as economic, social and political power. Fascist regimes as well as film corporations have employed cinema as a tool of propaganda to control and mobilize the masses for the sake of their power longevity. Moreover, the character of film itself is a perfect fascist medium which came from the network of proto-fascism of the twentieth century civilization. By using various genres of Indonesian cinema from different eras as a case study, this article argues that Indonesian propaganda films have monolithic representation which can be described as a cult of "bapakisme" (patronism, "kultur komando" (command culture, marginalisation of women' role in Indonesian revolutionary movement and demonization of progressive women organisation, and glorification of the role of Soeharto in Indonesian revolutionary movement.

  19. Electricity production and microbial characterization of thermophilic microbial fuel cells.

    Science.gov (United States)

    Dai, Kun; Wen, Jun-Li; Zhang, Fang; Ma, Xi-Wen; Cui, Xiang-Yu; Zhang, Qi; Zhao, Ting-Jia; Zeng, Raymond J

    2017-11-01

    Thermophilic microbial fuel cell (TMFC) offers many benefits, but the investigations on the diversity of exoelectrogenic bacteria are scarce. In this study, a two-chamber TMFC was constructed using ethanol as an electron donor, and the microbial dynamics were analyzed by high-throughput sequencing and 16S rRNA clone-library sequencing. The open-circuit potential of TMFC was approximately 650mV, while the maximum voltage was around 550mV. The maximum power density was 437mW/m2, and the columbic efficiency in this work was 20.5±6.0%. The Firmicutes bacteria, related to the uncultured bacterium clone A55_D21_H_B_C01 with a similarity of 99%, accounted for 90.9% of all bacteria in the TMFC biofilm. This unknown bacterium has the potential to become a new thermophilic exoelectrogenic bacterium that is yet to be cultured. The development of TMFC-involved biotechnologies will be beneficial for the production of valuable chemicals and generation of energy in the future. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Microbial Cretaceous park: biodiversity of microbial fossils entrapped in amber.

    Science.gov (United States)

    Martín-González, Ana; Wierzchos, Jacek; Gutiérrez, Juan C; Alonso, Jesús; Ascaso, Carmen

    2009-05-01

    Microorganisms are the most ancient cells on this planet and they include key phyla for understanding cell evolution and Earth history, but, unfortunately, their microbial records are scarce. Here, we present a critical review of fossilized prokaryotic and eukaryotic microorganisms entrapped in Cretaceous ambers (but not exclusively from this geological period) obtained from deposits worldwide. Microbiota in ambers are rather diverse and include bacteria, fungi, and protists. We comment on the most important microbial records from the last 25 years, although it is not an exhaustive bibliographic compilation. The most frequently reported eukaryotic microfossils are shells of amoebae and protists with a cell wall or a complex cortex. Likewise, diverse dormant stages (palmeloid forms, resting cysts, spores, etc.) are abundant in ambers. Besides, viral and protist pathogens have been identified inside insects entrapped in amber. The situation regarding filamentous bacteria and fungi is quite confusing because in some cases, the same record was identified consecutively as a member of these phylogenetically distant groups. To avoid these identification errors in the future, we propose to apply a more resolute microscopic and analytical method in amber studies. Also, we discuss the most recent findings about ancient DNA repair and bacterial survival in remote substrates, which support the real possibility of ancient DNA amplification and bacterial resuscitation from Cretaceous resins.

  1. Microbial Regulation in Gorgonian Corals

    Directory of Open Access Journals (Sweden)

    Laura D. Mydlarz

    2012-06-01

    Full Text Available Gorgonian corals possess many novel natural products that could potentially mediate coral-bacterial interactions. Since many bacteria use quorum sensing (QS signals to facilitate colonization of host organisms, regulation of prokaryotic cell-to-cell communication may represent an important bacterial control mechanism. In the present study, we examined extracts of twelve species of Caribbean gorgonian corals, for mechanisms that regulate microbial colonization, such as antibacterial activity and QS regulatory activity. Ethanol extracts of gorgonians collected from Puerto Rico and the Florida Keys showed a range of both antibacterial and QS activities using a specific Pseudomonas aeruginosa QS reporter, sensitive to long chain AHLs and a short chain N-acylhomoserine lactones (AHL biosensor, Chromobacterium violaceium. Overall, the gorgonian corals had higher antimicrobial activity against non-marine strains when compared to marine strains. Pseudopterogorgia americana, Pseusopterogorgia acerosa, and Pseudoplexuara flexuosa had the highest QS inhibitory effect. Interestingly, Pseudoplexuara porosa extracts stimulated QS activity with a striking 17-fold increase in signal. The stimulation of QS by P. porosa or other elements of the holobiont may encourage colonization or recruitment of specific microbial species. Overall, these results suggest the presence of novel stimulatory QS, inhibitory QS and bactericidal compounds in gorgonian corals. A better understanding of these compounds may reveal insight into coral-microbial ecology and whether a therapeutic potential exists.

  2. Designing the Microbial Research Commons

    Energy Technology Data Exchange (ETDEWEB)

    Uhlir, Paul F. [Board on Research Data and Information Policy and Global Affairs, Washington, DC (United States)

    2011-10-01

    Recent decades have witnessed an ever-increasing range and volume of digital data. All elements of the pillars of science--whether observation, experiment, or theory and modeling--are being transformed by the continuous cycle of generation, dissemination, and use of factual information. This is even more so in terms of the re-using and re-purposing of digital scientific data beyond the original intent of the data collectors, often with dramatic results. We all know about the potential benefits and impacts of digital data, but we are also aware of the barriers, the challenges in maximizing the access, and use of such data. There is thus a need to think about how a data infrastructure can enhance capabilities for finding, using, and integrating information to accelerate discovery and innovation. How can we best implement an accessible, interoperable digital environment so that the data can be repeatedly used by a wide variety of users in different settings and with different applications? With this objective: to use the microbial communities and microbial data, literature, and the research materials themselves as a test case, the Board on Research Data and Information held an International Symposium on Designing the Microbial Research Commons at the National Academy of Sciences in Washington, DC on 8-9 October 2009. The symposium addressed topics such as models to lower the transaction costs and support access to and use of microbiological materials and digital resources from the perspective of publicly funded research, public-private interactions, and developing country concerns. The overall goal of the symposium was to stimulate more research and implementation of improved legal and institutional models for publicly funded research in microbiology.

  3. Partnervalg på film

    DEFF Research Database (Denmark)

    Kramer, Mette

    2006-01-01

    Nye kognitions- og evolutionspsykologiske aspekter på kvinders filmpræferencer for romantiske film og melodramer......Nye kognitions- og evolutionspsykologiske aspekter på kvinders filmpræferencer for romantiske film og melodramer...

  4. Science and Science Fiction Films.

    Science.gov (United States)

    Dubeck, Leroy W.

    1981-01-01

    Describes an undergraduate physics course for nonscience majors which combines physics with science fiction films. Includes course format, sample module on the concept of momentum, and an appendix with a listing of science fiction films used in this course. (DS)

  5. Thin film metal-oxides

    CERN Document Server

    Ramanathan, Shriram

    2009-01-01

    Presents an account of the fundamental structure-property relations in oxide thin films. This title discusses the functional properties of thin film oxides in the context of applications in the electronics and renewable energy technologies.

  6. Transparent, Conductive Carbon Nanotube Films

    National Research Council Canada - National Science Library

    Zhuangchun Wu; Zhihong Chen; Xu Du; Jonathan M. Logan; Jennifer Sippel; Maria Nikolou; Katalin Kamaras; John R. Reynolds; David B. Tanner; Arthur F. Hebard; Andrew G. Rinzler

    2004-01-01

    We describe a simple process for the fabrication of ultrathin, transparent, optically homogeneous, electrically conducting films of pure single-walled carbon nanotubes and the transfer of those films...

  7. Thin film ceramic thermocouples

    Science.gov (United States)

    Gregory, Otto (Inventor); Fralick, Gustave (Inventor); Wrbanek, John (Inventor); You, Tao (Inventor)

    2011-01-01

    A thin film ceramic thermocouple (10) having two ceramic thermocouple (12, 14) that are in contact with each other in at least on point to form a junction, and wherein each element was prepared in a different oxygen/nitrogen/argon plasma. Since each element is prepared under different plasma conditions, they have different electrical conductivity and different charge carrier concentration. The thin film thermocouple (10) can be transparent. A versatile ceramic sensor system having an RTD heat flux sensor can be combined with a thermocouple and a strain sensor to yield a multifunctional ceramic sensor array. The transparent ceramic temperature sensor that could ultimately be used for calibration of optical sensors.

  8. Thin film photovoltaic device

    Science.gov (United States)

    Catalano, A.W.; Bhushan, M.

    1982-08-03

    A thin film photovoltaic solar cell which utilizes a zinc phosphide semiconductor is of the homojunction type comprising an n-type conductivity region forming an electrical junction with a p-type region, both regions consisting essentially of the same semiconductor material. The n-type region is formed by treating zinc phosphide with an extrinsic dopant such as magnesium. The semiconductor is formed on a multilayer substrate which acts as an opaque contact. Various transparent contacts may be used, including a thin metal film of the same chemical composition as the n-type dopant or conductive oxides or metal grids. 5 figs.

  9. Films and nursing education

    Directory of Open Access Journals (Sweden)

    María GABRIELA FELIPPA

    2016-01-01

    Full Text Available The purpose of this paper is to provide some ideas about the importance of film, with it’s audiovisual narrative, in the nursing education. The use of films during teaching gives the posibility to increase the construction of a professional view.The nursing carreer of Isalud University of Argentina is founded a sistematic work with cinematographic support. In this case are presented different ways of work with cinematographic support in a curricular space of Fundamentals of Nursing of the career of a professional Nurse of the Isalud University.

  10. Films et cultistes

    OpenAIRE

    Châteauvert, Jean; Bates, Tamara

    2015-01-01

    La critique cinématographique a contribué à populariser l’expression « film-culte », situant tel ou tel film comme un incontournable dans l’histoire du cinéma. Or, si l’expression est devenue commune, on est constamment confronté à une réalité polymorphe. Car le vocable désigne aussi bien un classique tel Casablanca (Curtiz, 1942) ou Rebel without a Cause (Ray, 1955) que The Rocky Horror Picture Show (Sharman, 1973), voire quelques « navets » de science-fiction, qu’on nomme les psychotronique...

  11. Intellectual Video Filming

    DEFF Research Database (Denmark)

    Juel, Henrik

    Like everyone else university students of the humanities are quite used to watching Hollywood productions and professional TV. It requires some didactic effort to redirect their eyes and ears away from the conventional mainstream style and on to new and challenging ways of using the film media...... in favour of worthy causes. However, it is also very rewarding to draw on the creativity, enthusiasm and rapidly improving technical skills of young students, and to guide them to use video equipment themselves for documentary, for philosophical film essays and intellectual debate. In the digital era...

  12. Thin Film Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Zweibel, K.

    1998-11-19

    The motivation to develop thin film technologies dates back to the inception of photovoltaics. It is an idea based on achieving truly low-cost photovoltaics appropriate for mass production and energy significant markets. The key to the idea is the use of pennies worth of active materials. Since sunlight carries relatively little energy in comparison with combustion-based energy sources, photovoltaic (PV) modules must be cheap to produce energy that can be competitive. Thin films are presumed to be the answer to that low-cost requirement. But how cheap do they have to be? The following is an oversimplified analysis that allows some insight into this question.

  13. Microbial biosensors for organophosphate pesticides.

    Science.gov (United States)

    Mulchandani, Ashok; Rajesh

    2011-09-01

    Organophosphates, amongst the most toxic substance known, are used widely in agriculture around the world. Their extensive use, however, has resulted in their occurrence in the water and food supply threatening humans and animals. Therefore, there is a need for determination of these neurotoxic compounds sensitively, selectively, and rapidly in the field. The present work is a brief review on the recent advancements in amperometric, potentiometric, and optical biosensors using genetically engineered microorganisms expressing organophosphate hydrolyzing enzyme intracellularly or anchored on the cell surface for the detection of organophosphate pesticides. The benefits and limitations associated with such microbial biosensors are delineated.

  14. Hydrogen production from microbial strains

    Science.gov (United States)

    Harwood, Caroline S; Rey, Federico E

    2012-09-18

    The present invention is directed to a method of screening microbe strains capable of generating hydrogen. This method involves inoculating one or more microbes in a sample containing cell culture medium to form an inoculated culture medium. The inoculated culture medium is then incubated under hydrogen producing conditions. Once incubating causes the inoculated culture medium to produce hydrogen, microbes in the culture medium are identified as candidate microbe strains capable of generating hydrogen. Methods of producing hydrogen using one or more of the microbial strains identified as well as the hydrogen producing strains themselves are also disclosed.

  15. Microbial Influenced Corrosion (MIC) Study

    Science.gov (United States)

    2012-05-23

    corrosion morphology (i e tunneling suggests MIC) . ., Inner Surfaces BUSINESS SENSITIVE 6 Outer Surfaces Outer Surfaces Microbial Influenced...environmental conditions expected within areas of aircraft −Identify and assess the effect of possible short- and long- term mitigation technologies...DAY 28 Chrome Conversion Coating  Coupon Type: A    Alodine  1200 (Henkel)  Non‐Chrome Treatment  Coupon Type: E    Prekote® (Pantheon Chemical

  16. Microbial Forensics: A Scientific Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Keim, Paul

    2003-02-17

    Microorganisms have been used as weapons in criminal acts, most recently highlighted by the terrorist attack using anthrax in the fall of 2001. Although such ''biocrimes'' are few compared with other crimes, these acts raise questions about the ability to provide forensic evidence for criminal prosecution that can be used to identify the source of the microorganisms used as a weapon and, more importantly, the perpetrator of the crime. Microbiologists traditionally investigate the sources of microorganisms in epidemiological investigations, but rarely have been asked to assist in criminal investigations. A colloquium was convened by the American Academy of Microbiology in Burlington, Vermont, on June 7-9, 2002, in which 25 interdisciplinary, expert scientists representing evolutionary microbiology, ecology, genomics, genetics, bioinformatics, forensics, chemistry, and clinical microbiology, deliberated on issues in microbial forensics. The colloquium's purpose was to consider issues relating to microbial forensics, which included a detailed identification of a microorganism used in a bioattack and analysis of such a microorganism and related materials to identify its forensically meaningful source--the perpetrators of the bioattack. The colloquium examined the application of microbial forensics to assist in resolving biocrimes with a focus on what research and education are needed to facilitate the use of microbial forensics in criminal investigations and the subsequent prosecution of biocrimes, including acts of bioterrorism. First responders must consider forensic issues, such as proper collection of samples to allow for optimal laboratory testing, along with maintaining a chain of custody that will support eventual prosecution. Because a biocrime may not be immediately apparent, a linkage must be made between routine diagnosis, epidemiological investigation, and criminal investigation. There is a need for establishing standard operating

  17. Antikken på film

    DEFF Research Database (Denmark)

    Krasilnikoff, Jens

    2012-01-01

    Review af forskning om den græsk-romerske oldtid på film. Dertil en skitse til videre arbejde med antikken på film ud fra et historiefagligt og kulturhistorisk udgangspunkt.......Review af forskning om den græsk-romerske oldtid på film. Dertil en skitse til videre arbejde med antikken på film ud fra et historiefagligt og kulturhistorisk udgangspunkt....

  18. Film beyond boundaries: film, migrant narratives and other media Film beyond boundaries: film, migrant narratives and other media

    OpenAIRE

    Anelise Reich Corseuil

    2008-01-01

    The articles here presented are representative of the debates about the various transformational aspects of film studies, fostering the discussion about the transformations and interactions between national and international narrative forms, the interrelations between film and literature, and film with other media. The critical perspectives here presented range from an emphasis on cultural materialism, dialogism, reception theory, deconstructionism, narrative studies to film aesthetics or fil...

  19. Rare Earth Oxide Thin Films

    CERN Document Server

    Fanciulli, Marco

    2007-01-01

    Thin rare earth (RE) oxide films are emerging materials for microelectronic, nanoelectronic, and spintronic applications. The state-of-the-art of thin film deposition techniques as well as the structural, physical, chemical, and electrical properties of thin RE oxide films and of their interface with semiconducting substrates are discussed. The aim is to identify proper methodologies for the development of RE oxides thin films and to evaluate their effectiveness as innovative materials in different applications.

  20. Push Tester For Laminated Films

    Science.gov (United States)

    Sugimura, Russell S.

    1991-01-01

    Small instrument used to measure brittleness of polymer film adhesively bonded to hard substrate. Penlike instrument has microball tip. Small pointer in slot on side of instrument used to calibrate and indicate spring force applied by point. Microball dents only small area of specimen. Such measurements used to measure rates of embrittlement in environmental tests of candidate laminated-film covers for photovoltaic modules. Not limited to transparent films; also used on opaque laminated films on back panels of photovoltaic modules.

  1. Functionalized magnetite silica thin films fabricated by MAPLE with antibiofilm properties.

    Science.gov (United States)

    Mihaiescu, D E; Cristescu, R; Dorcioman, G; Popescu, C E; Nita, C; Socol, G; Mihailescu, I N; Grumezescu, A M; Tamas, D; Enculescu, M; Negrea, R F; Ghica, C; Chifiriuc, C; Bleotu, C; Chrisey, D B

    2013-03-01

    We report on the fabrication of magnetite/salicylic acid/silica shell/antibiotics (Fe(3)O(4)/SA/SiO(2)/ATB) thin films by matrix-assisted pulsed laser evaporation (MAPLE) to inert substrates. Fe(3)O(4)-based powder have been synthesized and investigated by XRD and TEM. All thin films were studied by FTIR, SEM and in vitro biological assays using Staphylococcus aureus and Pseudomonas aeruginosa reference strains, as well as eukaryotic HEp-2 cells. The influence of the obtained nanosystems on the microbial biofilm development as well as their biocompatibility has been assessed. For optimum deposition conditions, we obtained uniform adherent films with the composition identical with the raw materials. Fe(3)O(4)/SA/SiO(2)/ATB thin films had an inhibitory activity on the ability of microbial strains to initiate and develop mature biofilms, in a strain- and antibiotic-dependent manner. These magnetite silica thin films are promising candidates for the development of novel materials designed for the inhibition of medical biofilms formed by different pathogenic agents on common substrates, frequently implicated in the etiology of chronic and hard to treat infections.

  2. Anti-Biofilm Activity of Polyazolidinammonium Modified with Iodine Hydrate Ions against Microbial Biofilms of Uropathogenic Coliform Bacteria.

    Science.gov (United States)

    Nechaeva, O V; Tikhomirova, E I; Zayarsky, D A; Bespalova, N V; Glinskaya, E V; Shurshalova, N F; Al Bayati, B M; Babailova, A I

    2017-04-01

    The dynamics of microbial biofilm formation by standard strain and by clinical strains of uropathogenic coliform bacteria was investigated in vitro and the effect of sublethal concentrations of the polymer compound polyazolidinammonium modified with iodine hydrate ions on the initial stages of biofilm formation was assessed. Treatment of immunological plate wells with the polymeric compound prevented film formation, especially in case of clinical E. coli strain carrying FimH virulence gene.

  3. Film in Education: This Worked For Me.

    Science.gov (United States)

    Breen, Myles P.

    Several techniques for teaching film appreciation to adults are discussed, including the use of audio cassettes, instructional films, silent films, and film dissection. Included are the techniques, philosophy, and content of a seminar on the short film, in which the short film is viewed as a variant of a short story, a pop song, a joke, and a…

  4. Synthesis and bactericidal ability of Ag/TiO 2 composite films deposited on titanium plate

    Science.gov (United States)

    Mai, Lixiang; Wang, Dawei; Zhang, Sheng; Xie, Yongjian; Huang, Chunming; Zhang, Zhiguang

    2010-11-01

    In this study, we develop a bactericidal coating material for micro-implant, TiO 2 films with Ag deposited on were prepared on titanium plates by sol-gel process. Their anti-microbial properties were analyzed as a function of the annealed temperature using Escherichia coli as a benchmark microorganism. Ag nanoparticles deposited on TiO 2 film were of metallic nature and could grow to larger ones when the annealed temperature increased. The results indicated that the smaller size of Ag nanoparticles, the better bactericidal ability. On the other hand, the positive antibacterial effect of TiO 2 enhanced the bactericidal effect of Ag.

  5. Film Images of the Negro.

    Science.gov (United States)

    Manchel, Frank

    1967-01-01

    Educators can help students recognize the value of the motion picture as a social influence by exposing them to film stereotyping and the effect of this distortion on society. A historical study of the film image of the Negro will show him emerging from a humorous, fearful, "perverted" character in early films to "an unfortunate member of society"…

  6. Radical Pedagogy, Prison, and Film

    Science.gov (United States)

    O'Neill, Dierdre

    2015-01-01

    This article explores the work of The Inside Film project. Inside Film works with a specific group of people (prisoners and ex-prisoners) in a particular set of circumstances (in prison or on parole) exploring how film making can be used within prison education or with people who have been to prison as a means of fostering a critical engagement…

  7. Instructional Films: Asset or Liability?

    Science.gov (United States)

    Braselman, Herbert P.

    1978-01-01

    The unique capabilities of film and research findings in educational psychology, learning psychology, and cost effectiveness indicate that film is an asset to the educational process. Sufficient resources and continued training should be provided to enable teachers to use the most effective film at the optimal time. (CMV)

  8. Reading Lawyer Films Comment lire les films juridiques

    OpenAIRE

    James Elkins

    2012-01-01

    With the advent of film studies in the United States, there has been a growing interest in legal academic circles in lawyer, legal, and courtroom films. In Professor Elkins’s essay, we find a claim that Hollywood lawyer films have pedagogical value.With the emerging interest in lawyer and legal films, there is virtually nothing written about what or how films are to be taught, and what their value might be. Professor Elkins provides the basic axioms for a humanistic approach to reading lawyer...

  9. Manipulatiaon of Biofilm Microbial Ecology

    Energy Technology Data Exchange (ETDEWEB)

    Burkhalter, R.; Macnaughton, S.J.; Palmer, R.J.; Smith, C.A.; Whitaker, K.W.; White, D.C.; Zinn, M.; kirkegaard, R.

    1998-08-09

    The Biofilm mode of growth provides such significant advantages to the members of the consortium that most organisms in important habitats are found in biofilms. The study of factors that allow manipulation of biofilm microbes in the biofilm growth state requires that reproducible biofilms by generated. The most effective monitoring of biofilm formation, succession and desquamation is with on-line monitoring of microbial biofilms with flowcell for direct observation. The biofilm growth state incorporates a second important factor, the heterogeneity in the distribution in time and space of the component members of the biofilm consortium. This heterogeneity is reflected not only in the cellular distribution but in the metabolic activity within a population of cells. Activity and cellular distribution can be mapped in four dimensions with confocal microscopy, and function can be ascertained by genetically manipulated reporter functions for specific genes or by vital stains. The methodology for understanding the microbial ecology of biofilms is now much more readily available and the capacity to manipulate biofilms is becoming an important feature of biotechnology.

  10. Manipulation of Biofilm Microbial Ecology

    Energy Technology Data Exchange (ETDEWEB)

    White, D.C.; Palmer, R.J., Jr.; Zinn, M.; Smith, C.A.; Burkhalter, R.; Macnaughton, S.J.; Whitaker, K.W.; Kirkegaard, R.D.

    1998-08-15

    The biofilm mode of growth provides such significant advantages to the members of the consortium that most organisms in important habitats are found in biofilms. The study of factors that allow manipulation of biofilm microbes in the biofilm growth state requires that reproducible biofilms be generated. The most effective monitoring of biofilm formation, succession and desaturation is with on-line monitoring of microbial biofilms with flowcell for direct observation. The biofilm growth state incorporates a second important factor, the heterogeneity in distribution in time and space of the component members of the biofilm consortium. This heterogeneity is reflected not only in the cellular distribution but in the metabolic activity within a population of cells. Activity and cellular distribution can be mapped in four dimensions with confocal microscopy, and function can be ascertained by genetically manipulated reporter functions for specific genes or by vital stains. The methodology for understanding the microbial ecology of biofilms is now much more readily available and the capacity to manipulate biofilms is becoming an important feature of biotechnology.

  11. Diamond films: Historical perspective

    Energy Technology Data Exchange (ETDEWEB)

    Messier, R. [Pennsylvania State Univ., University Park (United States)

    1993-01-01

    This section is a compilation of notes and published international articles about the development of methods of depositing diamond films. Vapor deposition articles are included from American, Russian, and Japanese publications. The international competition to develop new deposition methodologies is stressed. The current status of chemical vapor deposition of diamond is assessed.

  12. 8 mm Film - Postscript

    Science.gov (United States)

    Grimmett, George

    1969-01-01

    Supplements article in v1 n3 concerning practical methods of using transparencies and 8mm film in ETV presentations. (LS) Note: In referring to a previous issue of the journal being indexed, is it necessary to repeat the title of the journal in the annotation? Some standardization (i.e., aguideline) would be helpful

  13. FILM I KUFFERTEN

    DEFF Research Database (Denmark)

    Johansen, Stine Liv; Hansen, Adriana Maria

    2013-01-01

    kulturen, medierne er i kulturen – også i legekulturen. Denne rapport beskriver og undersøger et særligt eksempel på medialiseret leg. På baggrund af feltstudier i fem danske børnehaver, hvor et nyt filmpædagogisk materiale – Film i Kufferten - introduceres, er det rapportens formål at eksemplificere...

  14. Film i skolen

    DEFF Research Database (Denmark)

    Møller, Thilde Emilie

    med atskabe film, og at elevernes samarbejde særligt kommer til udtryk igennem kropslige handlinger omkringiPad’en. I afhandlingen præciseres filmproduktion på iPad som en cirkulær bevægelse mellem optagelse, refleksionog redigering. Denne forståelse udfordrer den lineært orienterede filmpædagogik...

  15. Filmens krop, kroppens film

    DEFF Research Database (Denmark)

    Moestrup, Steffen Damkjær

    2014-01-01

    Vi har i nyere tid set en lind strøm af dokumentarfilm, der iscenesætter afvigende kroppe. Det gælder film som Shape of the Shapeless (2010), Herbstgold (2010), Beating Time (2010), Planet of Snail (2011), Whole (2003) og Kinbaku – the Art of Bondage (2009). Fælles for filmene er, at de dels...

  16. Our Favorite Film Shocks

    DEFF Research Database (Denmark)

    Willerslev, Rane; Suhr, Christian

    2014-01-01

    The modern medium of film has long been hailed for its capacity for producing shocks of an entertaining, thought-provoking, or even politically emancipative nature. But what is a shock, how and when does it occur, how long does it last, and are there particular techniques for producing cinematic...

  17. Storyboarding an Animated Film

    DEFF Research Database (Denmark)

    Frølunde, Lisbeth

    2009-01-01

    This paper applies notions of transformation to the analysis of data on semiotic processes related to making an animated film. The data derives from a study conducted in an upper secondary school in Copenhagen with students (18 years old) participating in a week-long workshop. The paper applies...

  18. Korupsi dalam Film Indonesia

    Directory of Open Access Journals (Sweden)

    Rhafidilla Vebrynda

    2015-01-01

    Full Text Available Abstract: Corruption has been rooted and institutionalized in our smallest environment. The campaign to fight corruption comes from various organizations through numerous varieties of means. This study looks at the Komisi Pemberantasan Korupsi (KPK campaign through a film entitled “Kita Versus Korupsi”. This study uses narrative analysis by looking at the elements of narrative, narrative structure, the analysis model of aktan and the Greimas’ semiotic square. It is found that the film narrates corruption as trouble and resistor. The various forms of corruption are narrated using the combination of techniques scene, dialogue and flashback. Abstrak: Korupsi sudah mengakar dan melembaga hingga lingkungan terkecil kita. Kampanye untuk melawannya datang dari berbagai pihak melalui beragam sarana. Penelitian ini melihat kampanye Komisi Pemberantasan Korupsi (KPK melalui film “Kita Versus Korupsi”. Menggunakan metode analisis naratif dengan melihat unsur naratif, struktur naratif, analisis model aktan dan oposisi segi empat Algirdas Greimas, penelitian ini menemukan bahwa korupsi dinarasikan sebagai gangguan dan penghambat. Film tersebut selalu menghadapkan pelaku korupsi dengan pihak yang tidak korupsi secara langsung. Latar belakang pengetahuan tokoh utama tentang korupsi berpengaruh dalam pengambilan keputusannya. Berbagai bentuk korupsi dinarasikan dengan teknik penggabungan scene, dialog dan flashback.

  19. A Film Canister Colorimeter.

    Science.gov (United States)

    Gordon, James; James, Alan; Harman, Stephanie; Weiss, Kristen

    2002-01-01

    A low-cost, low-tech colorimeter was constructed from a film canister. The student-constructed colorimeter was used to show the Beer-Lambert relationship between absorbance and concentration and to calculate the value of the molar absorptivity for permanganate at the wavelength emission maximum for an LED. Makes comparisons between this instrument…

  20. Surrealism and Film.

    Science.gov (United States)

    Matthews, J. H.

    This book is a critical, genre study of surrealist films including a general discussion of the backgrounds, influences, and overall traits of surrealism as a mode of artistic response to an absurdist world. Citing the impetus of Jacques Vache and Andre Breton as the originators of surrealism, the work expands upon the themes of fractured realism…

  1. Developing Film Study Guides.

    Science.gov (United States)

    Tatsuki, Donna

    Popular films can be used successfully in a wide range of language, content, and culture classes. Creating support materials in order to use a movie in such a class is an enormous task, but with careful planning it can be broken into four manageable components: contemplation, selection, segmentation, and construction. This brief paper provides a…

  2. Soap Films and Bubbles.

    Science.gov (United States)

    Rice, Karen

    1986-01-01

    Develops and explains a format for a workshop which focuses on soap films and bubbles. The plan consists of: a discussion to uncover what children know about bubbles; explanations of the demonstration equipment; the presentation itself; the assembly of the workshop kit; and time to play with the bubbles. (ML)

  3. Patterned Nanomagnetic Films

    NARCIS (Netherlands)

    Lodder, J.C.; Sellmyer, D.; Skomski, R.

    2006-01-01

    Nano-fabrication technologies for realising patterned structures from thin films are reviewed. A classification is made to divide the patterning technologies in two groups namely with and without the use of masks. The more traditional methods as well as a few new methods are discussed al in relation

  4. Mobile Library Filming Device.

    Science.gov (United States)

    Martin, Claud E.

    This report contains details of the study and performance test of the Mobile Filming Library Device which consists of a camera and self contained power source. Because of the cost savings and service improvement characteristics, this technique involving the use of a microfilm intermediate in the preparation of copies of material filed in full size…

  5. "Gudbai, Lenin!" - film goda

    Index Scriptorium Estoniae

    2003-01-01

    Euroopa Filmiakadeemia tänavused auhinnasaajad : Saksa film "Good bye, Lenin!" võitis 6 auhinda, kaasaarvatud parima filmi tiitel. Parim režissöör - Lars von Trier "Dogville'i" eest, aasta üllatus - Andrei Zvjagintsevi "Tagasitulek"

  6. Film: The Creative Eye.

    Science.gov (United States)

    Sohn, David A.

    Short films are often experimental in nature. They can place aspects of the environment which are usually unnoticed in such a way as to sharpen our observations of the world, and "create a new awareness, a fuller sense of life and being." Based on the premise that visual literacy is becoming increasingly important, this book describes several…

  7. Flow fields in soap films: Relating viscosity and film thickness.

    Science.gov (United States)

    Prasad, V; Weeks, Eric R

    2009-08-01

    We follow the diffusive motion of colloidal particles in soap films with varying h / d, where h is the thickness of the film and d is the diameter of the particles. The hydrodynamics of these films are determined by looking at the correlated motion of pairs of particles as a function of separation R. The Trapeznikov approximation [A. A. Trapeznikov, (Butterworths, London, 1957), p. 242] is used to model soap films as an effective two-dimensional (2D) fluid in contact with bulk air phases. The flow fields determined from correlated particle motions show excellent agreement with what is expected for the theory of 2D fluids for all our films where 0.6 films (h / d > 7 + or - 3) . Our results indicate that three-dimensional effects become important for these thicker films, despite the flow fields still having a 2D character.

  8. Microbial corrosion in weld zone of stainless steel. Stainless ko yosetsubu no biseibutsu fushoku

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, E. (National Chemical Laboratory for Industry, Tsukuba (Japan)); Nishimura, M. (Mitsubishi Kakoki Kaisha, Ltd., Tokyo (Japan))

    1992-10-15

    Microbial corrosion may happen wherever water is treated in many kinds of practical metal except titan, such as common steel, copper alloy, stainless steel, and high-nickel alloy. Although microbes causing microbial corrosion are not limited to specified microbes, specially affecting microbes are iron bacteria, iron-oxidizing bacteria, and sulfate-reducing bacteria. mechanism in these microbial corrosion, which is fundamentally caused through formation of oxygen concentration cells and production of metabolites, is complex and different by each microbe. In the case of stainless steel, the corrosion is located mainly in weld zones or heat affected zones, the shape of corrosion is like a pot, and the pattern is a type of pitting corrosion. Microbes are apt to adhere to the surface near weld zones, then oxygen becomes consequently insufficient beneath the surface, where the self-mending capacity of passive films is deprived, resulting in occurrence of pitting corrosion. For protection of microbial corrosion, it is essential to control water so that habitation of microbes is not formed. 9 refs., 3 figs.

  9. Microbial Biosensors for Selective Detection of Disaccharides

    Science.gov (United States)

    Seven microbial strains were screened for their ability to detect disaccharides as components of Clark-type oxygen biosensors. Sensors responded to varying degrees to maltose, cellobiose, sucrose, and melibiose, but none responded strongly to lactose. Although microbial sensors are relatively nons...

  10. on microbial populations in the cotton rhizosphere

    African Journals Online (AJOL)

    Swilla

    Moreover, the studied culturable bacterial and fungal groups were positively correlated (p>0.001) with soil respiration and microbial biomass, which exhibited uneven trend with the treatments. Generally Soil from 06Z604D showed the slight higher microbial populations and CFU count, whilst HART 89M showed slight lower ...

  11. Microbial synthetic biology for human therapeutics.

    Science.gov (United States)

    Jain, Aastha; Bhatia, Pooja; Chugh, Archana

    2012-06-01

    The emerging field of synthetic biology holds tremendous potential for developing novel drugs to treat various human conditions. The current study discusses the scope of synthetic biology for human therapeutics via microbial approach. In this context, synthetic biology aims at designing, engineering and building new microbial synthetic cells that do not pre-exist in nature as well as re-engineer existing microbes for synthesis of therapeutic products. It is expected that the construction of novel microbial genetic circuitry for human therapeutics will greatly benefit from the data generated by 'omics' approaches and multidisciplinary nature of synthetic biology. Development of novel antimicrobial drugs and vaccines by engineering microbial systems are a promising area of research in the field of synthetic biology for human theragnostics. Expression of plant based medicinal compounds in the microbial system using synthetic biology tools is another avenue dealt in the present study. Additionally, the study suggest that the traditional medicinal knowledge can do value addition for developing novel drugs in the microbial systems using synthetic biology tools. The presented work envisions the success of synthetic biology for human therapeutics via microbial approach in a holistic manner. Keeping this in view, various legal and socio-ethical concerns emerging from the use of synthetic biology via microbial approach such as patenting, biosafety and biosecurity issues have been touched upon in the later sections.

  12. Fundamentals of microbial community resistance and resilience

    Directory of Open Access Journals (Sweden)

    Ashley eShade

    2012-12-01

    Full Text Available Microbial communities are at the heart of all ecosystems, and yet microbial community behavior in disturbed environments remains difficult to measure and predict. Understanding the drivers of microbial community stability, including resistance (insensitivity to disturbance and resilience (the rate of recovery after disturbance is important for predicting community response to disturbance. Here, we provide an overview of the concepts of stability that are relevant for microbial communities. First, we highlight insights from ecology that are useful for defining and measuring stability. To determine whether general disturbance responses exist for microbial communities, we next examine representative studies from the literature that investigated community responses to press (long-term and pulse (short-term disturbances in a variety of habitats. Then we discuss the biological features of individual microorganisms, of microbial populations, and of microbial communities that may govern overall community stability. We conclude with thoughts about the unique insights that systems perspectives - informed by meta-omics data- may provide about microbial community stability.

  13. Uses of antimicrobial genes from microbial genome

    Science.gov (United States)

    Sorek, Rotem; Rubin, Edward M.

    2013-08-20

    We describe a method for mining microbial genomes to discover antimicrobial genes and proteins having broad spectrum of activity. Also described are antimicrobial genes and their expression products from various microbial genomes that were found using this method. The products of such genes can be used as antimicrobial agents or as tools for molecular biology.

  14. Tracking microbial impact on crop production

    Science.gov (United States)

    One of the benefits of no-till systems is that activity of the soil microbial community increases. Producers gain an array of improvements in their production systems due to enhanced microbial functioning. For example, corn yield can increase approximately 25% with the same inputs with more microb...

  15. [Sanitary-hygienic assessment of microbial biofertilizer].

    Science.gov (United States)

    Arkhipchenko, N A; Akhtemava, G A; Lebedeva, T V; Voronina, A A; Makhan'kova, T I; Pavlova, M M; Shteĭntsaĭg, T A

    1991-10-01

    Biological treatment of sewage from pig-breeding complexes allowed to produce microbial biomass and primary sediments. The mixture of these components (1:1) after rendering harmless and drying out become the high effective biofertilizer. The results of chronic experiment on sanitary status of soil (microbial and helminthological indexes) under this biofertilizer usage are discussed, and the harmlessness of it is demonstrated.

  16. Microbial Cellulose Utilization: Fundamentals and Biotechnology

    OpenAIRE

    Lee R Lynd; Weimer, Paul J.; van Zyl, Willem H.; Pretorius, Isak S.

    2002-01-01

    Fundamental features of microbial cellulose utilization are examined at successively higher levels of aggregation encompassing the structure and composition of cellulosic biomass, taxonomic diversity, cellulase enzyme systems, molecular biology of cellulase enzymes, physiology of cellulolytic microorganisms, ecological aspects of cellulase-degrading communities, and rate-limiting factors in nature. The methodological basis for studying microbial cellulose utilization is considered relative to...

  17. Microbial granulation for lactic acid production

    DEFF Research Database (Denmark)

    Kim, Dong-Hoon; Lee, Mo-Kwon; Hwang, Yuhoon

    2016-01-01

    This work investigated the formation of microbial granules to boost the productivity of lactic acid (LA). The flocculated form of LA-producing microbial consortium, dominated by Lactobacillus sp. (91.5% of total sequence), was initially obtained in a continuous stirred-tank reactor (CSTR), which ...

  18. Developing microbial inoculants for native Hawaiian trees

    Science.gov (United States)

    Kim H. Wilkinson

    2002-01-01

    We use certain microbial inoculants in the nursery as a part of supporting the objectives of accelerating rehabilitation of degraded land and ecosystem function, as well as reducing costs in establishment and maintenance of forest plantings. Microbial inoculants re-create natural partnerships between plants and some of the beneficial microorganisms that support plants...

  19. A LIXISOL MICROBIAL ACTIVITY UNDER URBAN WASTES ...

    African Journals Online (AJOL)

    31 déc. 2014 ... This study focuses soil microbial activity measurement in relation with the application ... friendly composts adoption could improve soil organic carbon content for sustainable microbial process. ... microbienne (à travers la biomasse microbienne et la respiration du sol) et à identifier la formule de compost qui ...

  20. Fundamentals of Microbial Community Resistance and Resilience

    Science.gov (United States)

    Shade, Ashley; Peter, Hannes; Allison, Steven D.; Baho, Didier L.; Berga, Mercè; Bürgmann, Helmut; Huber, David H.; Langenheder, Silke; Lennon, Jay T.; Martiny, Jennifer B. H.; Matulich, Kristin L.; Schmidt, Thomas M.; Handelsman, Jo

    2012-01-01

    Microbial communities are at the heart of all ecosystems, and yet microbial community behavior in disturbed environments remains difficult to measure and predict. Understanding the drivers of microbial community stability, including resistance (insensitivity to disturbance) and resilience (the rate of recovery after disturbance) is important for predicting community response to disturbance. Here, we provide an overview of the concepts of stability that are relevant for microbial communities. First, we highlight insights from ecology that are useful for defining and measuring stability. To determine whether general disturbance responses exist for microbial communities, we next examine representative studies from the literature that investigated community responses to press (long-term) and pulse (short-term) disturbances in a variety of habitats. Then we discuss the biological features of individual microorganisms, of microbial populations, and of microbial communities that may govern overall community stability. We conclude with thoughts about the unique insights that systems perspectives – informed by meta-omics data – may provide about microbial community stability. PMID:23267351

  1. Microbial growth and substrate utilization kinetics | Okpokwasili ...

    African Journals Online (AJOL)

    Microbial growth on and utilization of environmental contaminants as substrates have been studied by many researchers. Most times, substrate utilization results in removal of chemical contaminant, increase in microbial biomass and subsequent biodegradation of the contaminant. These are all aimed at detoxification of the ...

  2. The enrichment of surface passive film on stainless steel during biofilm development in coastal seawater.

    Science.gov (United States)

    Eashwar, M; Sreedhar, G; Lakshman Kumar, A; Hariharasuthan, R; Kennedy, J

    2015-01-01

    The surface passive film on UNS S30400 alloy was characterized before and after biofilm development under different regimes of diurnal lighting in quiescent flowing coastal seawater. As exemplified by atomic force microscopy, the passive film grew under all test conditions with conspicuous variations in morphological features. X-ray photon spectroscopy illustrated an enrichment of the outer film by iron oxide and a progressive increase in the iron oxide/chromium oxide ratio with lighting. Mott-Schottky plots reflected the duplex nature of the film, comprising an outer n-type and an inner p-type configuration. The slopes of the plots showed a strong decrease in donor and acceptor densities with biofilm coverage and lighting, thus confirming passive film growth. These results provide new insights that passive film enrichment is an intrinsic process under practical marine conditions, and show that the evolution of the passive film is a key step to sustained passivity and/or its breakdown by microbial mechanisms.

  3. Physicochemical Properties of Edible Chitosan/Hydroxypropyl Methylcellulose/Lysozyme Films Incorporated with Acidic Electrolyzed Water

    Directory of Open Access Journals (Sweden)

    Ewa Brychcy

    2015-01-01

    Full Text Available The treatment with acidic electrolyzed water (AEW is a promising disinfection method due to its effectiveness in reducing microbial population. The aim of the study was to evaluate physicochemical properties of chitosan/HPMC films incorporated with lysozyme and acidic electrolyzed water. In the composite films, decreasing film solubility and increasing concentration of sodium chloride solution and prolongation of electrolysis time were observed. Electrolysis process with sodium chloride induces spongy network of film structure. The use of AEW has not changed chemical composition of films which was proved by 1H NMR, MALDI-TOF, and FT-IR spectroscopy. The research confirmed that electrolysis significantly improved thermomechanical properties of the examined films. The contact angle values of the films were quite similar and ranged between 56° and 73°. The increase of salt concentration used in the electrolysis process had an impact on increasing flexibility of samples. Application of electrolyzed water in commonly used food processing systems is possible. Fusion of AEW and biopolymers may provide better integration with coated food product and multidirectional protecting effect.

  4. Microbial Burden Approach : New Monitoring Approach for Measuring Microbial Burden

    Science.gov (United States)

    Venkateswaran, Kasthuri; Vaishampayan, Parag; Barmatz, Martin

    2013-01-01

    Advantages of new approach for differentiating live cells/ spores from dead cells/spores. Four examples of Salmonella outbreaks leading to costly destruction of dairy products. List of possible collaboration activities between JPL and other industries (for future discussion). Limitations of traditional microbial monitoring approaches. Introduction to new approach for rapid measurement of viable (live) bacterial cells/spores and its areas of application. Detailed example for determining live spores using new approach (similar procedure for determining live cells). JPL has developed a patented approach for measuring amount of live and dead cells/spores. This novel "molecular" method takes less than 5 to 7 hrs. compared to the seven days required using conventional techniques. Conventional "molecular" techniques can not discriminate live cells/spores among dead cells/spores. The JPL-developed novel method eliminates false positive results obtained from conventional "molecular" techniques that lead to unnecessary delay in the processing and to unnecessary destruction of food products.

  5. Ion beam assisted film growth

    CERN Document Server

    Itoh, T

    2012-01-01

    This volume provides up to date information on the experimental, theoretical and technological aspects of film growth assisted by ion beams.Ion beam assisted film growth is one of the most effective techniques in aiding the growth of high-quality thin solid films in a controlled way. Moreover, ion beams play a dominant role in the reduction of the growth temperature of thin films of high melting point materials. In this way, ion beams make a considerable and complex contribution to film growth. The volume will be essential reading for scientists, engineers and students working in thi

  6. Handbook of thin film technology

    CERN Document Server

    Frey, Hartmut

    2015-01-01

    “Handbook of Thin Film Technology” covers all aspects of coatings preparation, characterization and applications. Different deposition techniques based on vacuum and plasma processes are presented. Methods of surface and thin film analysis including coating thickness, structural, optical, electrical, mechanical and magnetic properties of films are detailed described. The several applications of thin coatings and a special chapter focusing on nanoparticle-based films can be found in this handbook. A complete reference for students and professionals interested in the science and technology of thin films.

  7. Microbial Biogeography of the Arctic Cryosphere

    DEFF Research Database (Denmark)

    Hauptmann, Aviaja Zenia Edna Lyberth

    Microbial biogeography has become a recognized field of research within the science of microbial ecology. Technological advances such as the high throughput sequencing of genetic information with next-generation sequencing (NGS) technologies have made us able to “see” the diversity of microbial...... communities. This has considerably improved our understanding that even harsh and seemingly barren environments such as the cryosphere, the frozen parts of our planet, is inhabited by diverse life. This thesis presents three studies in microbial biogeography of the Arctic cryosphere utilizing a range of NGS...... to a previously unacknowledged degree. The overall aim of this thesis is to illustrate the advantages that NGS has given in the field of microbial biogeography with the Arctic cryosphere as an example. The most important point in the following is that in order to utilize these advantages to their full potential...

  8. Microbial methanogenesis in subsurface oil and coal.

    Science.gov (United States)

    Meslé, Margaux; Dromart, Gilles; Oger, Philippe

    2013-11-01

    It is now clear that active methanogens are present in the deep-subsurface. This paper reviews microbial population structures and the biodegradation of organic compounds to methane in situ within oil reservoirs and coal deposits. It summarizes our current knowledge of methanogenes and methanogenesis, fermenters, synthrophs and microbial metabolism of complex organic compounds in these two widely occurring organic-rich subsurface environments. This review is not intended to be an exhaustive report of microbial diversity. Rather, it illustrates the similarities and differences between the two environments with specific examples, from the nature of the organic molecules to the methanogenic metabolic pathways and the structure of the microbial populations to demonstrate that widely diverging microbial populations show surprisingly similar metabolic capabilities. Copyright © 2013 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  9. Microbial inoculant carrier for pesticide degradation

    Energy Technology Data Exchange (ETDEWEB)

    Zhixing, Y.; Velagaleti, R.; Gorman, M. [ABC Laboratories, Inc., Columbia, MO (United States)] [and others

    1995-12-31

    Biological degradation of pesticides may be enhanced by using a suitable carrier that sustains microbial growth. The char matrix (TRB Char) was evaluated as a biocarrier, and is produced by three sequential cocurrent gasifications of coal. The nature of TRB Char and the large pores provides an ideal matrix for mixing, drying, and retaining liquid wastes. The macropore structure of TRB Char is also ideal for microbial growth. Plate counts were conducted to monitor the extent of microbial growth following 20 and 504 hours of growth. Additionally, electron micrograph scans showed location of microbial growth on the char particle. By 21 days 10{sup 8} colony forming units per gram of bacteria had grown. The electron micrographs showed that the macropore structure of TRB Char is an ideal shelter for microbial growth throughout the char particle. TRB Char could serve as a biocarrier for pesticide degradation.

  10. Microbial populations in contaminant plumes

    Science.gov (United States)

    Haack, Sheridan K.; Bekins, Barbara A.

    Efficient biodegradation of subsurface contaminants requires two elements: (1) microbial populations with the necessary degradative capabilities, and (2) favorable subsurface geochemical and hydrological conditions. Practical constraints on experimental design and interpretation in both the hydrogeological and microbiological sciences have resulted in limited knowledge of the interaction between hydrogeological and microbiological features of subsurface environments. These practical constraints include: (1) inconsistencies between the scales of investigation in the hydrogeological and microbiological sciences, and (2) practical limitations on the ability to accurately define microbial populations in environmental samples. However, advances in application of small-scale sampling methods and interdisciplinary approaches to site investigations are beginning to significantly improve understanding of hydrogeological and microbiological interactions. Likewise, culture-based and molecular analyses of microbial populations in subsurface contaminant plumes have revealed significant adaptation of microbial populations to plume environmental conditions. Results of recent studies suggest that variability in subsurface geochemical and hydrological conditions significantly influences subsurface microbial-community structure. Combined investigations of site conditions and microbial-community structure provide the knowledge needed to understand interactions between subsurface microbial populations, plume geochemistry, and contaminant biodegradation. La biodégradation efficace des polluants souterrains requiert deux éléments: des populations microbiennes possédant les aptitudes nécessaires à la dégradation, et des conditions géochimiques et hydrologiques souterraines favorables. Des contraintes pratiques sur la conception et l'interprétation des expériences à la fois en microbiologie et en hydrogéologie ont conduit à une connaissance limitée des interactions entre les

  11. Lonsdaleite Films with Nanometer Thickness.

    Science.gov (United States)

    Kvashnin, Alexander G; Sorokin, Pavel B

    2014-02-06

    We investigate the properties of potentially the stiffest quasi-2-D films with lonsdaleite structure. Using a combination of ab initio and empirical potential approaches, we analyze the elastic properties of lonsdaleite films in both elastic and inelastic regimes and compare them with graphene and diamond films. We review possible fabrication methods of lonsdaleite films using the pure nanoscale "bottom-up" paradigm: by connecting carbon layers in multilayered graphene. We propose the realization of this method in two ways: by applying direct pressure and by using the recently proposed chemically induced phase transition. For both cases, we construct the phase diagrams depending on temperature, pressure, and film thickness. Finally, we consider the electronic properties of lonsdaleite films and establish the nonlinear dependence of the band gap on the films' thicknesses and their lower effective masses in comparison with bulk crystal.

  12. Method for making carbon films

    Science.gov (United States)

    Tan, M.X.

    1999-07-29

    A method for treating an organic polymer material, preferably a vinylidene chloride/vinyl chloride copolymer (Saran) to produce a flat sheet of carbon film material having a high surface area ([approx equal]1000 m[sup 2] /g) suitable as an electrode material for super capacitor applications. The method comprises heating a vinylidene chloride/vinyl chloride copolymer film disposed between two spaced apart graphite or ceramic plates to a first temperature of about 160 C for about 14 hours to form a stabilized vinylidene chloride/vinyl chloride polymer film, thereafter heating the stabilized film to a second temperature of about 750 C in an inert atmosphere for about one hour to form a carbon film; and finally activating the carbon film to increase the surface area by heating the carbon film in an oxidizing atmosphere to a temperature of at least 750--850 C for between 1--6 hours. 2 figs.

  13. Thin film superconductor magnetic bearings

    Science.gov (United States)

    Weinberger, Bernard R.

    1995-12-26

    A superconductor magnetic bearing includes a shaft (10) that is subject to a load (L) and rotatable around an axis of rotation, a magnet (12) mounted to the shaft, and a stator (14) in proximity to the shaft. The stator (14) has a superconductor thin film assembly (16) positioned to interact with the magnet (12) to produce a levitation force on the shaft (10) that supports the load (L). The thin film assembly (16) includes at least two superconductor thin films (18) and at least one substrate (20). Each thin film (18) is positioned on a substrate (20) and all the thin films are positioned such that an applied magnetic field from the magnet (12) passes through all the thin films. A similar bearing in which the thin film assembly (16) is mounted on the shaft (10) and the magnet (12) is part of the stator (14) also can be constructed.

  14. Professor Camillo Negro's Neuropathological Films.

    Science.gov (United States)

    Chiò, Adriano; Gianetto, Claudia; Dagna, Stella

    2016-01-01

    Camillo Negro, Professor in Neurology at the University of Torino, was a pioneer of scientific film. From 1906 to 1908, with the help of his assistant Giuseppe Roasenda and in collaboration with Roberto Omegna, one of the most experienced cinematographers in Italy, he filmed some of his patients for scientific and educational purposes. During the war years, he continued his scientific film project at the Military Hospital in Torino, filming shell-shocked soldiers. In autumn 2011, the Museo Nazionale del Cinema, in partnership with the Faculty of Neurosciences of the University of Torino, presented a new critical edition of the neuropathological films directed by Negro. The Museum's collection also includes 16 mm footage probably filmed in 1930 by Doctor Fedele Negro, Camillo's son. One of these films is devoted to celebrating the effects of the so-called "Bulgarian cure" on Parkinson's disease.

  15. Thin Film Polyamide Membranes with Photoresponsive Antibacterial Activity

    KAUST Repository

    Duong, Phuoc H. H.

    2017-08-09

    Membranes containing a photosensitizer molecule as part of the selective layer are proposed with demonstrated anti-biofouling activity. For the membrane preparation, mixtures of an amine-functionalized photosensitizer molecule, (5,10,15,20-(tetra-4-aminophenyl)porphyrin) and m-phenylene diamine (MPD) reacted with trimesoyl chloride (TMC) by interfacial polymerization to form thin polyamide films on top of an asymmetric porous support. A highly permeable membrane (35.4 Lm−2h−1bar−1) with 99 % rejection of Brilliant Blue R (826 g/mol) was obtained using 0.25 wt% porphyrin and 0.75 wt% MPD as amine monomers. Under visible light exposure, singlet oxygen (1O2) is generated in the porphyrin containing-polyamide film, reaching the bacteria in the feed by diffusion and enhancing the biofouling resistance and anti-microbial activity. Anti-biofouling and anti-microbial photoactivity in solution are demonstrated on Staphylococcus aureus at different porphyrin concentrations and light exposure time.

  16. Resolution in forensic microbial genotyping

    Energy Technology Data Exchange (ETDEWEB)

    Velsko, S P

    2005-08-30

    Resolution is a key parameter for differentiating among the large number of strain typing methods that could be applied to pathogens involved in bioterror events or biocrimes. In this report we develop a first-principles analysis of strain typing resolution using a simple mathematical model to provide a basis for the rational design of microbial typing systems for forensic applications. We derive two figures of merit that describe the resolving power and phylogenetic depth of a strain typing system. Rough estimates of these figures-of-merit for MLVA, MLST, IS element, AFLP, hybridization microarrays, and other bacterial typing methods are derived from mutation rate data reported in the literature. We also discuss the general problem of how to construct a ''universal'' practical typing system that has the highest possible resolution short of whole-genome sequencing, and that is applicable with minimal modification to a wide range of pathogens.

  17. Analysis of Illumina Microbial Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Clum, Alicia; Foster, Brian; Froula, Jeff; LaButti, Kurt; Sczyrba, Alex; Lapidus, Alla; Woyke, Tanja

    2010-05-28

    Since the emerging of second generation sequencing technologies, the evaluation of different sequencing approaches and their assembly strategies for different types of genomes has become an important undertaken. Next generation sequencing technologies dramatically increase sequence throughput while decreasing cost, making them an attractive tool for whole genome shotgun sequencing. To compare different approaches for de-novo whole genome assembly, appropriate tools and a solid understanding of both quantity and quality of the underlying sequence data are crucial. Here, we performed an in-depth analysis of short-read Illumina sequence assembly strategies for bacterial and archaeal genomes. Different types of Illumina libraries as well as different trim parameters and assemblers were evaluated. Results of the comparative analysis and sequencing platforms will be presented. The goal of this analysis is to develop a cost-effective approach for the increased throughput of the generation of high quality microbial genomes.

  18. Theoretical microbial ecology without species

    Science.gov (United States)

    Tikhonov, Mikhail

    2017-09-01

    Ecosystems are commonly conceptualized as networks of interacting species. However, partitioning natural diversity of organisms into discrete units is notoriously problematic and mounting experimental evidence raises the intriguing question whether this perspective is appropriate for the microbial world. Here an alternative formalism is proposed that does not require postulating the existence of species as fundamental ecological variables and provides a naturally hierarchical description of community dynamics. This formalism allows approaching the species problem from the opposite direction. While the classical models treat a world of imperfectly clustered organism types as a perturbation around well-clustered species, the presented approach allows gradually adding structure to a fully disordered background. The relevance of this theoretical construct for describing highly diverse natural ecosystems is discussed.

  19. Microbial processes and subsurface contaminants

    Science.gov (United States)

    Molz, Fred J.

    A Chapman Conference entitled “Microbial Processes in the Transport, Fate, and In Situ Treatment of Subsurface Contaminants” was held in Snowbird, Utah, October 1-3, 1986. Members of the program committee and session chairmen were Lenore Clesceri (Rensselaer Polytechnic Institute, Troy, N.Y.), David Gibson (University of Texas, Austin), James Mercer (GeoTrans, Inc., Herndon , Va.), Donald Michelsen (Virginia Polytechnic Institute and State University, Blacksburg), Fred Molz (Auburn University, Auburn, Ala.), Bruce Rittman (University of Illinois, Urbana), Gary Sayler (University of Tennessee, Knoxville), and John T. Wilson (U.S. Environmental Protection Agency, Ada, Okla.). The following report attempts to highlight the six sessions that constituted the conference. For additional information, including a bound summary and abstracts, contact Fred J. Molz, Civil Engineering Department, Auburn University, AL 36849 (telephone: 205-826-4321).

  20. Microbial bioreporters of trace explosives.

    Science.gov (United States)

    Shemer, Benjamin; Koshet, Ori; Yagur-Kroll, Sharon; Belkin, Shimshon

    2017-06-01

    Since its introduction as an explosive in the late 19th century, 2,4,6-trinitrotoluene (TNT), along with other explosive compounds, has left numerous environmental marks. One of these is widespread soil and water pollution by trace explosives in military proving grounds, manufacturing facilities, or actual battlefields. Another dramatic impact is that exerted by the millions of landmines and other explosive devices buried in large parts of the world, causing extensive loss of life, injuries, and economical damage. In this review we highlight recent advances in the design and construction of microbial bioreporters, molecularly engineered to generate a quantifiable dose-dependent signal in the presence of trace amounts of explosives. Such sensor strains may be employed for monitoring environmental pollution as well as for the remote detection of buried landmines. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Enzymology of Microbial Dimethylsulfoniopropionate Catabolism.

    Science.gov (United States)

    Dey, Mishtu

    2017-01-01

    The biochemistry of dimethylsulfoniopropionate (DMSP) catabolism is reviewed. The microbes that catalyze the reactions central to DMSP catabolic pathways are described, and the focus is on the enzymology of the process. Approximately 10(9)tons of DMSP is released annually by marine eukaryotes as an osmolyte. A vast majority of DMSP is assimilated by bacteria through either a demethylation or lyase pathways, producing either the methane thiol or the volatile dimethylsulfide (DMS), respectively. Enzymatic breakdown of DMSP generates ~10(7)tons of DMS annually, which may have impact on global climate. DMS also acts as a chemoattractant for zooplanktons and seabirds. Both DMSP and DMS play a key role in the global sulfur cycle and are key nutrients for marine microbial growth. Important enzymes in the biochemical pathways of DMSP catabolism are covered in this review, with a focus on the latest developments in their mechanism. © 2017 Elsevier Inc. All rights reserved.

  2. Conditioning biomass for microbial growth

    Energy Technology Data Exchange (ETDEWEB)

    Bodie, Elizabeth A; England, George

    2015-03-31

    The present invention relates to methods for improving the yield of microbial processes that use lignocellulose biomass as a nutrient source. The methods comprise conditioning a composition comprising lignocellulose biomass with an enzyme composition that comprises a phenol oxidizing enzyme. The conditioned composition can support a higher rate of growth of microorganisms in a process. In one embodiment, a laccase composition is used to condition lignocellulose biomass derived from non-woody plants, such as corn and sugar cane. The invention also encompasses methods for culturing microorganisms that are sensitive to inhibitory compounds in lignocellulose biomass. The invention further provides methods of making a product by culturing the production microorganisms in conditioned lignocellulose biomass.

  3. Antibiotic tolerance and microbial biofilms

    DEFF Research Database (Denmark)

    Folkesson, Anders

    Increased tolerance to antimicrobial agents is thought to be an important feature of microbes growing in biofilms. We study the dynamics of antibiotic action within hydrodynamic flow chamber biofilms of Escherichia coli and Pseudomonas aeruginosa using isogenic mutants and fluorescent gene...... expression reporters and we address the question of how biofilm organization affects antibiotic susceptibility. The dynamics of microbial killing is monitored by viable count determination, and confocal laser microscopy. Our work shows that the apparent increased antibiotic tolerance is due to the formation...... of antibiotic tolerant subpopulations within the biofilm. The formation of these subpopulations is highly variable and dependent on the antibiotic used, the biofilm structural organization and the induction of specific tolerance mechanisms....

  4. Microbial ecology of watery kimchi.

    Science.gov (United States)

    Kyung, Kyu Hang; Medina Pradas, Eduardo; Kim, Song Gun; Lee, Yong Jae; Kim, Kyong Ho; Choi, Jin Joo; Cho, Joo Hyong; Chung, Chang Ho; Barrangou, Rodolphe; Breidt, Frederick

    2015-05-01

    The biochemistry and microbial ecology of 2 similar types of watery (mul) kimchi, containing sliced and unsliced radish and vegetables (nabak and dongchimi, respectively), were investigated. Samples from kimchi were fermented at 4, 10, and 20 °C were analyzed by plating on differential and selective media, high-performance liquid chromatography, and high-throughput DNA sequencing of 16S rDNA. Nabak kimchi showed similar trends as dongchimi, with increasing lactic and acetic acids and decreasing pH for each temperature, but differences in microbiota were apparent. Interestingly, bacteria from the Proteobacterium phylum, including Enterobacteriaceae, decreased more rapidly during fermentation at 4 °C in nabak cabbage fermentations compared with dongchimi. Although changes for Proteobacterium and Enterobacteriaceae populations were similar during fermentation at 10 and 20 °C, the homolactic stage of fermentation did not develop for the 4 and 10 °C samples of both nabak and dongchimi during the experiment. These data show the differences in biochemistry and microbial ecology that can result from preparation method and fermentation conditions of the kimchi, which may impact safety (Enterobacteriaceae populations may include pathogenic bacteria) and quality (homolactic fermentation can be undesirable, if too much acid is produced) of the product. In addition, the data also illustrate the need for improved methods for identifying and differentiating closely related lactic acid bacteria species using high-throughput sequencing methods. © 2015 Institute of Food Technologists®. This article has been contributed by US Government employees and their work is in the public domain in the USA.

  5. Microbial detoxification of mycotoxin deoxynivalenol.

    Science.gov (United States)

    Völkl, Andrea; Vogler, Bernhard; Schollenberger, Margit; Karlovsky, Petr

    2004-01-01

    Deoxynivalenol (DON) is a trichothecene secondary metabolite produced by Fusarium species infecting cereal crops. As a mycotoxin, DON causes losses in livestock production and poses a health risk to humans consuming contaminated cereal products. DON also acts as a virulence factor, facilitating the colonization of host plants by Fusarium spp. Enzymatic detoxification of mycotoxins in feed additives and genetically modified crops is a promising approach for the reduction of mycotoxin contamination of feeds and food. A prerequisite for the development of biotechnological strategies for DON detoxification is the availability of genes encoding suitable enzymatic activities. With the goal of isolating microbial cultures that can be used as a source of such activities, we screened 1285 microbial cultures from farmland soil, cereal grains, insects and other sources for DON transformation under aerobic conditions. One mixed culture transformed DON into two chromatographically separable products. The main product of the transformation was purified and its structure was elucidated by mass spectroscopy, (1)H-NMR, (13)C-NMR and proton-proton and carbon-proton correlated NMR spectroscopy. The structure of this product was determined to be 3-keto-4-deoxynivalenol. The DON-transforming mixed culture survived and retained its transforming activity during a starvation period of six months at 20 degrees C. Transformation of DON was suppressed by low concentrations of glucose and high concentrations of tryptone and yeast extract. Cell-free supernatants obtained either by filtration through a 0.22 microm membrane filter or by centrifugation did not exert DON-transforming activity. Trichothecenes 15-acetyl-DON, 3-acetyl-DON and fusarenon-X were also transformed. Copyright 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

  6. Reading through Films

    Directory of Open Access Journals (Sweden)

    Madhavi Gayathri Raman

    2016-02-01

    Full Text Available This paper captures the design of a comprehensive curriculum incorporating the four skills based exclusively on the use of parallel audio-visual and written texts. We discuss the use of authentic materials to teach English to Indian undergraduates aged 18 to 20 years. Specifically, we talk about the use of parallel reading (screen-play and audio-visual texts (Shawshank Redemption, and Life is Beautiful, A Few Good Men and Lion King drawn from popular culture in the classroom as an effective teaching medium. Students were gradually introduced to films based on novels with extracts from the original texts (Schindler’s List, Beautiful Mind for extended reading and writing practice. We found that students began to pay more attention to aspects such as pronunciation, intonational variations, discourse markers and vocabulary items (phrasal verbs, synonyms, homophones, and puns. Keywords: Reading, films, popular culture, ESL classroom, language skills

  7. Musical and film time

    Directory of Open Access Journals (Sweden)

    Kulezić-Wilson Danijela

    2008-01-01

    Full Text Available Comparative analysis of linear, non-linear and multiple temporal dimensions in music and film reveals that the understanding and utilisation of time in these two arts reflect not only the aesthetic inclinations of its creators and their subjective experiences of temporality but also their philosophical views and, sometimes, spiritual beliefs. Viewed in the context of contemporary theories about Time, particularly Shallis' interpretation of different temporalities as symbolic of various levels of reality and J. T. Fraser's concept of time as a hierarchical nest of different temporalities or Umwelts, the results of this comparison lead to the conclusion that the time in which music and film unfold belongs to a separate, artificial Umwelt of its own - art-temporality.

  8. Magnetoresistance of Au films

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, D. L., E-mail: zhangdl@iphy.ac.cn; Song, X. H.; Zhang, X. [Institute of Physics, Chinese Academy of Sciences, Beijing 10081 (China); Zhang, X.-G., E-mail: xgz@ufl.edu [Department of Physics and Quantum Theory Project, University of Florida, Gainesville, Florida 32611 (United States); Center for Nanophase Materials Sciences and Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6493 (United States)

    2014-12-14

    Classical magnetoresistance (MR) in nonmagnetic metals are conventionally understood in terms of the Kohler rule, with violation usually viewed as anomalous electron transport, in particular, as evidence of non-Fermi liquid behavior. Measurement of the MR of Au films as a function of temperature and film thickness reveals a strong dependence on grain size distribution and clear violation of the Kohler rule. Using a model of random resistor network, we show that this result can be explained if the MR arises entirely from inhomogeneity due to grain boundary scattering and thermal activation of grain boundary atoms. Consequently, the Kohler rule should not be used to distinguish normal and anomalous electron transport in solids.

  9. Biomimetic thin film deposition

    Energy Technology Data Exchange (ETDEWEB)

    Rieke, P.R.; Graff, G.E.; Campbell, A.A.; Bunker, B.C.; Baskaran, S.; Song, L.; Tarasevich, B.J.; Fryxell, G.E.

    1995-09-01

    Biological mineral deposition for the formation of bone, mollusk shell and other hard tissues provides materials scientists with illustrative materials processing strategies. This presentation will review the key features of biomineralization and how these features can be of technical importance. We have adapted existing knowledge of biomineralization to develop a unique method of depositing inorganic thin films and coating. Our approach to thin film deposition is to modify substrate surfaces to imitate the proteins found in nature that are responsible for controlling mineral deposition. These biomimetic surfaces control the nucleation and growth of the mineral from a supersaturated aqueous solution. This has many processing advantages including simple processing equipment, environmentally benign reagents, uniform coating of highly complex shapes, and enhanced adherence of coating. Many different types of metal oxide, hydroxide, sulfide and phosphate materials with useful mechanical, optical, electronic and biomedical properties can be deposited.

  10. Fifty important research questions in microbial ecology.

    Science.gov (United States)

    Antwis, Rachael E; Griffiths, Sarah M; Harrison, Xavier A; Aranega-Bou, Paz; Arce, Andres; Bettridge, Aimee S; Brailsford, Francesca L; de Menezes, Alexandre; Devaynes, Andrew; Forbes, Kristian M; Fry, Ellen L; Goodhead, Ian; Haskell, Erin; Heys, Chloe; James, Chloe; Johnston, Sarah R; Lewis, Gillian R; Lewis, Zenobia; Macey, Michael C; McCarthy, Alan; McDonald, James E; Mejia-Florez, Nasmille L; O'Brien, David; Orland, Chloé; Pautasso, Marco; Reid, William D K; Robinson, Heather A; Wilson, Kenneth; Sutherland, William J

    2017-05-01

    Microbial ecology provides insights into the ecological and evolutionary dynamics of microbial communities underpinning every ecosystem on Earth. Microbial communities can now be investigated in unprecedented detail, although there is still a wealth of open questions to be tackled. Here we identify 50 research questions of fundamental importance to the science or application of microbial ecology, with the intention of summarising the field and bringing focus to new research avenues. Questions are categorised into seven themes: host-microbiome interactions; health and infectious diseases; human health and food security; microbial ecology in a changing world; environmental processes; functional diversity; and evolutionary processes. Many questions recognise that microbes provide an extraordinary array of functional diversity that can be harnessed to solve real-world problems. Our limited knowledge of spatial and temporal variation in microbial diversity and function is also reflected, as is the need to integrate micro- and macro-ecological concepts, and knowledge derived from studies with humans and other diverse organisms. Although not exhaustive, the questions presented are intended to stimulate discussion and provide focus for researchers, funders and policy makers, informing the future research agenda in microbial ecology. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Patterns and Processes of Microbial Community Assembly

    Science.gov (United States)

    Schmidt, Steven K.; Fukami, Tadashi; O'Neill, Sean P.; Bilinski, Teresa M.; Stanish, Lee F.; Knelman, Joseph E.; Darcy, John L.; Lynch, Ryan C.; Wickey, Phillip; Ferrenberg, Scott

    2013-01-01

    SUMMARY Recent research has expanded our understanding of microbial community assembly. However, the field of community ecology is inaccessible to many microbial ecologists because of inconsistent and often confusing terminology as well as unnecessarily polarizing debates. Thus, we review recent literature on microbial community assembly, using the framework of Vellend (Q. Rev. Biol. 85:183–206, 2010) in an effort to synthesize and unify these contributions. We begin by discussing patterns in microbial biogeography and then describe four basic processes (diversification, dispersal, selection, and drift) that contribute to community assembly. We also discuss different combinations of these processes and where and when they may be most important for shaping microbial communities. The spatial and temporal scales of microbial community assembly are also discussed in relation to assembly processes. Throughout this review paper, we highlight differences between microbes and macroorganisms and generate hypotheses describing how these differences may be important for community assembly. We end by discussing the implications of microbial assembly processes for ecosystem function and biodiversity. PMID:24006468

  12. Interspecies Interactions within Oral Microbial Communities

    Science.gov (United States)

    Kuramitsu, Howard K.; He, Xuesong; Lux, Renate; Anderson, Maxwell H.; Shi, Wenyuan

    2007-01-01

    Summary: While reductionism has greatly advanced microbiology in the past 400 years, assembly of smaller pieces just could not explain the whole! Modern microbiologists are learning “system thinking” and “holism.” Such an approach is changing our understanding of microbial physiology and our ability to diagnose/treat microbial infections. This review uses oral microbial communities as a focal point to describe this new trend. With the common name “dental plaque,” oral microbial communities are some of the most complex microbial floras in the human body, consisting of more than 700 different bacterial species. For a very long time, oral microbiologists endeavored to use reductionism to identify the key genes or key pathogens responsible for oral microbial pathogenesis. The limitations of reductionism forced scientists to begin adopting new strategies using emerging concepts such as interspecies interaction, microbial community, biofilms, polymicrobial disease, etc. These new research directions indicate that the whole is much more than the simple sum of its parts, since the interactions between different parts resulted in many new physiological functions which cannot be observed with individual components. This review describes some of these interesting interspecies-interaction scenarios. PMID:18063722

  13. Microbial considerations in genetically engineered mouse research.

    Science.gov (United States)

    Franklin, Craig L

    2006-01-01

    Microbial infections have long been of concern to scientists using laboratory rodents because of their potential to confound and invalidate research. With the explosion of genetically engineered mice (GEM), new concerns over the impact of microbial agents have emerged because these rodents in many cases are more susceptible to disease than their inbred or outbred counterparts. Moreover, interaction between microbe and host and the resulting manifestation of disease conceivably differ between GEM and their inbred and outbred counterparts. As a result, infections may alter the GEM phenotype and confound interpretation of results and conclusions about mutated gene function. In addition, because GEM are expensive to produce and maintain, contamination by pathogens or opportunists has severe economic consequences. This review addresses how microbial infections may influence phenotype, how immunomodulation of the host as the result of induced mutations may modify host susceptibility to microbial infections, how novel host:microbe interactions have led to the development of new animal models for disease, how phenotype changes have led to the discovery of new pathogens, and new challenges associated with prevention and control of microbial infections in GEM. Although the focus is on naturally occurring infections, extensive literature on the use of GEM in studies of microbial pathogenesis also exists, and the reader is referred to this literature if microbial infection is a suspected culprit in phenotype alteration.

  14. Development of tailored indigenous marine consortia for the degradation of naturally weathered polyethylene films.

    Science.gov (United States)

    Syranidou, Evdokia; Karkanorachaki, Katerina; Amorotti, Filippo; Repouskou, Eftychia; Kroll, Kevin; Kolvenbach, Boris; Corvini, Philippe F-X; Fava, Fabio; Kalogerakis, Nicolas

    2017-01-01

    This study investigated the potential of bacterial-mediated polyethylene (PE) degradation in a two-phase microcosm experiment. During phase I, naturally weathered PE films were incubated for 6 months with the indigenous marine community alone as well as bioaugmented with strains able to grow in minimal medium with linear low-density polyethylene (LLDPE) as the sole carbon source. At the end of phase I the developed biofilm was harvested and re-inoculated with naturally weathered PE films. Bacteria from both treatments were able to establish an active population on the PE surfaces as the biofilm community developed in a time dependent way. Moreover, a convergence in the composition of these communities was observed towards an efficient PE degrading microbial network, comprising of indigenous species. In acclimated communities, genera affiliated with synthetic (PE) and natural (cellulose) polymer degraders as well as hydrocarbon degrading bacteria were enriched. The acclimated consortia (indigenous and bioaugmented) reduced more efficiently the weight of PE films in comparison to non-acclimated bacteria. The SEM images revealed a dense and compact biofilm layer and signs of bio-erosion on the surface of the films. Rheological results suggest that the polymers after microbial treatment had wider molecular mass distribution and a marginally smaller average molar mass suggesting biodegradation as opposed to abiotic degradation. Modifications on the surface chemistry were observed throughout phase II while the FTIR profiles of microbially treated films at month 6 were similar to the profiles of virgin PE. Taking into account the results, we can suggest that the tailored indigenous marine community represents an efficient consortium for degrading weathered PE plastics.

  15. Development of tailored indigenous marine consortia for the degradation of naturally weathered polyethylene films.

    Directory of Open Access Journals (Sweden)

    Evdokia Syranidou

    Full Text Available This study investigated the potential of bacterial-mediated polyethylene (PE degradation in a two-phase microcosm experiment. During phase I, naturally weathered PE films were incubated for 6 months with the indigenous marine community alone as well as bioaugmented with strains able to grow in minimal medium with linear low-density polyethylene (LLDPE as the sole carbon source. At the end of phase I the developed biofilm was harvested and re-inoculated with naturally weathered PE films. Bacteria from both treatments were able to establish an active population on the PE surfaces as the biofilm community developed in a time dependent way. Moreover, a convergence in the composition of these communities was observed towards an efficient PE degrading microbial network, comprising of indigenous species. In acclimated communities, genera affiliated with synthetic (PE and natural (cellulose polymer degraders as well as hydrocarbon degrading bacteria were enriched. The acclimated consortia (indigenous and bioaugmented reduced more efficiently the weight of PE films in comparison to non-acclimated bacteria. The SEM images revealed a dense and compact biofilm layer and signs of bio-erosion on the surface of the films. Rheological results suggest that the polymers after microbial treatment had wider molecular mass distribution and a marginally smaller average molar mass suggesting biodegradation as opposed to abiotic degradation. Modifications on the surface chemistry were observed throughout phase II while the FTIR profiles of microbially treated films at month 6 were similar to the profiles of virgin PE. Taking into account the results, we can suggest that the tailored indigenous marine community represents an efficient consortium for degrading weathered PE plastics.

  16. Thin film processes

    CERN Document Server

    Vossen, John L

    1978-01-01

    Remarkable advances have been made in recent years in the science and technology of thin film processes for deposition and etching. It is the purpose of this book to bring together tutorial reviews of selected filmdeposition and etching processes from a process viewpoint. Emphasis is placed on the practical use of the processes to provide working guidelines for their implementation, a guide to the literature, and an overview of each process.

  17. Nonlinear optical thin films

    Science.gov (United States)

    Leslie, Thomas M.

    1993-01-01

    A focused approach to development and evaluation of organic polymer films for use in optoelectronics is presented. The issues and challenges that are addressed include: (1) material synthesis, purification, and the tailoring of the material properties; (2) deposition of uniform thin films by a variety of methods; (3) characterization of material physical properties (thermal, electrical, optical, and electro-optical); and (4) device fabrication and testing. Photonic materials, devices, and systems were identified as critical technology areas by the Department of Commerce and the Department of Defense. This approach offers strong integration of basic material issues through engineering applications by the development of materials that can be exploited as the active unit in a variety of polymeric thin film devices. Improved materials were developed with unprecedented purity and stability. The absorptive properties can be tailored and controlled to provide significant improvement in propagation losses and nonlinear performance. Furthermore, the materials were incorporated into polymers that are highly compatible with fabrication and patterning processes for integrated optical devices and circuits. By simultaneously addressing the issues of materials development and characterization, keeping device design and fabrication in mind, many obstacles were overcome for implementation of these polymeric materials and devices into systems. We intend to considerably improve the upper use temperature, poling stability, and compatibility with silicon based devices. The principal device application that was targeted is a linear electro-optic modulation etalon. Organic polymers need to be properly designed and coupled with existing integrated circuit technology to create new photonic devices for optical communication, image processing, other laser applications such as harmonic generation, and eventually optical computing. The progression from microscopic sample to a suitable film

  18. [Therapy through film].

    Science.gov (United States)

    Nicli, Pierrette

    2012-01-01

    For psychiatric patients, playing the role of their life, producing a film, editing it and presenting it to the public with the support of a group made up of patients and caregivers is a real form of self-distancing, a type of therapy. The video group from the Saint Ouen day hospital has been carrying out this creative and therapeutic work for several years. Screenings and exchanges between care centres are regularly organised.

  19. Ellipsometry of anodic film growth

    Energy Technology Data Exchange (ETDEWEB)

    Smith, C.G.

    1978-08-01

    An automated computer interpretation of ellisometer measurements of anodic film growth was developed. Continuous mass and charge balances were used to utilize more fully the time dependence of the ellipsometer data and the current and potential measurements. A multiple-film model was used to characterize the growth of films which proceeds via a dissolution--precipitation mechanism; the model also applies to film growth by adsorption and nucleation mechanisms. The characteristic parameters for film growth describe homogeneous and heterogeneous crystallization rates, film porosities and degree of hydration, and the supersaturation of ionic species in the electrolyte. Additional descriptions which may be chosen are patchwise film formation, nonstoichiometry of the anodic film, and statistical variations in the size and orientation of secondary crystals. Theories were developed to describe the optical effects of these processes. An automatic, self-compensating ellipsometer was used to study the growth in alkaline solution of anodic films on silver, cadmium, and zinc. Mass-transport conditions included stagnant electrolyte and forced convection in a flow channel. Multiple films were needed to characterize the optical properties of these films. Anodic films grew from an electrolyte supersatuated in the solution-phase dissolution product. The degree of supersaturation depended on transport conditions and had a major effect on the structure of the film. Anodic reaction rates were limited by the transport of charge carriers through a primary surface layer. The primary layers on silver, zinc, and cadmium all appeared to be nonstoichiometric, containing excess metal. Diffusion coefficients, transference numbers, and the free energy of adsorption of zinc oxide were derived from ellipsometer measurements. 97 figures, 13 tables, 198 references.

  20. Spring magnet films.

    Energy Technology Data Exchange (ETDEWEB)

    Bader, S. D.; Fullerton, E. E.; Gornakov, V. S.; Inomata, A.; Jiang, J. S.; Nikitenko, V. I.; Shapiro, A. J.; Shull, R. D.; Sowers, C. H.

    1999-03-29

    The properties of exchange-spring-coupled bilayer and superlattice films are highlighted for Sm-Co hard magnet and Fe or Co soft magnet layers. The hexagonal Sm-Co is grown via magnetron sputtering in a- and b-axis epitaxial orientations. In both cases the c-axis, in the film plane, is the easy axis of magnetization. Trends in coercivity with film thickness are established and related to the respective microstructure of the two orientations. The magnetization reversal process for the bilayers is examined by magnetometry and magneto-optical imaging, as well as by simulations that utilize a one-dimensional model to provide the spin configuration for each atomic layer. The Fe magnetization is pinned to that of the Sm-Co at the interface, and reversal proceeds via a progressive twisting of the Fe magnetization. The Fe demagnetization curves are reversible as expected for a spring magnet. Comparison of experiment and simulations indicates that the spring magnet behavior can be understood from the intrinsic properties of the hard and soft layers. Estimated are made of the ultimate gain in performance that can potentially be realized in this system.

  1. Polymer Thin Film Stabilization.

    Science.gov (United States)

    Costa, A. C.; Oslanec, R.; Composto, R. J.; Vlcek, P.

    1998-03-01

    We study the dewetting dynamics of thin polystyrene (PS) films deposited on silicon oxide surfaces using optical (OM) and atomic force (AFM) microscopes. Quantitative analysis of the hole diameter as a function of annealing time at 175^oC shows that blending poly(styrene-block-methyl-methacrylate) (PS-b-PMMA) with PS acts to dramatically slow down the dewetting rate and even stops holes growth before they impinge. AFM studies show that the hole floor is smooth for a pure PS film but contains residual polymer for the blend. At 5% vol., a PS-b-PMMA with high molar mass and low PMMA is a more effective stabilizing agent than a low molar mass/high PMMA additive. The optimum copolymer concentration is 3% vol. beyond which film stability doesn't improve. Although dewetting is slowed down relative to pure PS, PS/PS-b-PMMA bilayers dewet at a faster rate than blends having the same overall additive concentration.

  2. Mathematical modeling of microbial growth in milk

    Directory of Open Access Journals (Sweden)

    Jhony Tiago Teleken

    2011-12-01

    Full Text Available A mathematical model to predict microbial growth in milk was developed and analyzed. The model consists of a system of two differential equations of first order. The equations are based on physical hypotheses of population growth. The model was applied to five different sets of data of microbial growth in dairy products selected from Combase, which is the most important database in the area with thousands of datasets from around the world, and the results showed a good fit. In addition, the model provides equations for the evaluation of the maximum specific growth rate and the duration of the lag phase which may provide useful information about microbial growth.

  3. EVALUATION OF MICROBIAL SURVIVAL IN EXTRATERRESTRIAL ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    Betül BULUÇ

    2012-08-01

    Full Text Available In this paper, the space environments where microbial terrestrial life could form and evolve in, were evaluted with the base of the physical and chemical properties. In addition, Earthial microbial life formation conditions in the interstellar medium and the other planets are investigated and the survival of microorganisms in the space environments are questioned. As a result, considering the aspects of terrestrial microbial life, we suggest that the space environment and other planets could not be a habitat for Earthial microorganisms.

  4. Biotechnological Processes in Microbial Amylase Production

    Directory of Open Access Journals (Sweden)

    Subash C. B. Gopinath

    2017-01-01

    Full Text Available Amylase is an important and indispensable enzyme that plays a pivotal role in the field of biotechnology. It is produced mainly from microbial sources and is used in many industries. Industrial sectors with top-down and bottom-up approaches are currently focusing on improving microbial amylase production levels by implementing bioengineering technologies. The further support of energy consumption studies, such as those on thermodynamics, pinch technology, and environment-friendly technologies, has hastened the large-scale production of the enzyme. Herein, the importance of microbial (bacteria and fungi amylase is discussed along with its production methods from the laboratory to industrial scales.

  5. EVA Suit Microbial Leakage Investigation Project

    Science.gov (United States)

    Falker, Jay; Baker, Christopher; Clayton, Ronald; Rucker, Michelle

    2016-01-01

    The objective of this project is to collect microbial samples from various EVA suits to determine how much microbial contamination is typically released during simulated planetary exploration activities. Data will be released to the planetary protection and science communities, and advanced EVA system designers. In the best case scenario, we will discover that very little microbial contamination leaks from our current or prototype suit designs, in the worst case scenario, we will identify leak paths, learn more about what affects leakage--and we'll have a new, flight-certified swab tool for our EVA toolbox.

  6. Development of a Photosynthetic Microbial Electrochemical Cell (PMEC Reactor Coupled with Dark Fermentation of Organic Wastes: Medium Term Perspectives

    Directory of Open Access Journals (Sweden)

    Samir Bensaid

    2015-01-01

    Full Text Available In this article the concept, the materials and the exploitation potential of a photosynthetic microbial electrochemical cell for the production of hydrogen driven by solar power are investigated. In a photosynthetic microbial electrochemical cell, which is based on photosynthetic microorganisms confined to an anode and heterotrophic bacteria confined to a cathode, water is split by bacteria hosted in the anode bioactive film. The generated electrons are conveyed through external “bio-appendages” developed by the bacteria to transparent nano-pillars made of indium tin oxide (ITO, Fluorine-doped tin oxide (FTO or other conducting materials, and then transferred to the cathode. On the other hand, the generated protons diffuse to the cathode via a polymer electrolyte membrane, where they are reduced by the electrons by heterotrophic bacteria growing attached to a similar pillared structure as that envisaged for the anode and supplemented with a specific low cost substrate (e.g., organic waste, anaerobic digestion outlet. The generated oxygen is released to the atmosphere or stored, while the produced pure hydrogen leaves the electrode through the porous layers. In addition, the integration of the photosynthetic microbial electrochemical cell system with dark fermentation as acidogenic step of anaerobic digester, which is able to produce additional H2, and the use of microbial fuel cell, feed with the residues of dark fermentation (mainly volatile fatty acids, to produce the necessary extra-bias for the photosynthetic microbial electrochemical cell is here analyzed to reveal the potential benefits to this novel integrated technology.

  7. Ultrasound treated potato peel and sweet lime pomace based biopolymer film development.

    Science.gov (United States)

    Borah, Purba Prasad; Das, Pulak; Badwaik, Laxmikant S

    2017-05-01

    Treatment and management of food processing waste is a major challenge for food industry. Potato processing industry generates tremendous amount of peel and consider it as zero valued waste. Again, pomace generated after juice extraction from sweet lime pulp is considered as waste and not properly utilized. Whereas these waste could be utilized for the development of biodegradable packaging film to overcome environmental issues. Composite films were prepared with varying proportion of potato peel powder (PP) and sweet lime pomace (SLP) in the ratio of 0:1(A), 0.5:1(B), 1:1(C), 1:0.5(D), 1:0(E) with an ultrasound treatment of 45min, and 0:1(F), 0.5:1(G), 1:1(H), 1:0.5(I), 1:0(J) with an ultrasound treatment of 60min. Ultrasound was applied for 45 and 60min to film forming solutions to break down biopolymer particles small enough to form a film. All the films were analyzed for their barrier and mechanical properties. It was observed that increasing ultrasound treatment times gives better result in film properties and less PP content also gives better film properties, from these observations film G prepared with 0.5:1 (PP:SLP) showed better characteristics among all other films. Water vapor permeability, moisture absorption, water solubility, breakage strength and elongation capacity of G film were reported as 7.25×10 -9 g/Pahm, 12.88±0.348%, 38.92±0.702%, 242.01±3.074g and 7.61±0.824mm respectively. However, thermal decomposition for film G took place above 200°C. The film forming solution of selected G film, added with clove essential oil (1.5%) as an antimicrobial agent was wrapped on bread and stored it for 5days. The film was successful in lowering the weight loss, reducing the hardness and inhibition of surface microbial load from bread sample. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Stability of soap films: hysteresis and nucleation of black films.

    Science.gov (United States)

    Casteletto, Valeria; Cantat, Isabelle; Sarker, Dipak; Bausch, Richard; Bonn, Daniel; Meunier, Jacques

    2003-01-31

    We study the stability of soap films of a nonionic surfactant under different applied capillary pressures on the film. Depending on the pressure, either a thick common black film (CBF), or a micro-scopically thin Newton black film (NBF) is formed as a (metastable) equilibrium state, with a first-order (discontinuous) transition between the two. Studying the dynamics of the CBF-NBF transition, it is found that under certain conditions a hysteresis for the transition is observed: for a given range of pressures, either of the two states may be observed. We quantify the nucleation process that is at the basis of these observations both experimentally and theoretically.

  9. Relations entre les types de dépôts évaporitiques et la présence de couches riches en matière organique (roches-mères potentielles Relationship Between Different Types of Evaporitic Deposits and the Occurrence of Organic-Rich Layers (Potential Source Rocks

    Directory of Open Access Journals (Sweden)

    Busson G.

    2006-11-01

    évaporites de marge de bassin avec couches à matière organique au centre correspondent à une période prolongée. C'est l'essentiel de la vie du bassin. Le remplissage de la cuvette centrale par des évaporites de centre de bassin peut être un épisode bref et qui peut entraîner la disparition même du bassin. Les évaporites de plate-forme s'étalant indifféremment sur l'ancien domaine du bassin comme sur celui des anciennes plates-formes marginales peuvent être l'aube d'un nouveau cycle sédimentaire, indifférent au passé. The extraordinary fertility of saline waters has been confirmed by recent studies of salterns in the western Mediterranean. The benthos contains mollusks, foraminifers, ostracodes and especially Cyanophyceae and bacterial populations. Plankton includes microphytoplankton (Dunaliella, diatoms, etc. , zooplankton (flagellates, Artemia salina and numerous heterotrophic bacteria. Where diversity is low when salinity is high, the proliferation of well adapted forms can be greater than the productivity levels observed in most other environments. The effectiveness of stratified water bodies for the preservation of organic matter originally produced in photic and oxygenated water is brought out. Such stratified systems may be accompanied by the proliferation of photosynthetic bacteria that are exposed to sporadic mass mortality, resulting in the formation of organic laminae at the bottom. In shelf (or epeiric evaporites, where the segregation of salinities and deposits has been synchronous and lateral, the water depth must have been shallow and hence unsuitable for the formation of stratified water bodies and especially for their geological duration. Such accumulations thus generally have a low organic content, and they also do not have abundant reef systems. In basin-center evaporites, the deposits are attributed to a succession of phases of increasing salinity in time, i. e. limestone in high areas, contemporaneous with thin organic

  10. Evolving Microbial Communities in Cellulose-Fed Microbial Fuel Cell

    Directory of Open Access Journals (Sweden)

    Renata Toczyłowska-Mamińska

    2018-01-01

    Full Text Available The abundance of cellulosic wastes make them attractive source of energy for producing electricity in microbial fuel cells (MFCs. However, electricity production from cellulose requires obligate anaerobes that can degrade cellulose and transfer electrons to the electrode (exoelectrogens, and thus most previous MFC studies have been conducted using two-chamber systems to avoid oxygen contamination of the anode. Single-chamber, air-cathode MFCs typically produce higher power densities than aqueous catholyte MFCs and avoid energy input for the cathodic reaction. To better understand the bacterial communities that evolve in single-chamber air-cathode MFCs fed cellulose, we examined the changes in the bacterial consortium in an MFC fed cellulose over time. The most predominant bacteria shown to be capable electron generation was Firmicutes, with the fermenters decomposing cellulose Bacteroidetes. The main genera developed after extended operation of the cellulose-fed MFC were cellulolytic strains, fermenters and electrogens that included: Parabacteroides, Proteiniphilum, Catonella and Clostridium. These results demonstrate that different communities evolve in air-cathode MFCs fed cellulose than the previous two-chamber reactors.

  11. Chemical and microbial properties of farmer's field soils fertilized ...

    African Journals Online (AJOL)

    The study investigated the chemical and microbial characteristic of soils receiving different quantity of waste for several years (20, 10 and 7 years). Soils were sampled around the city of Ouagadougou (Burkina Faso). Soil chemical (C, N, P and pH) and microbial (basal respiration, microbial biomass and microbial diversity) ...

  12. Understanding Microbial Sensing in Inflammatory Bowel Disease Using Click Chemistry

    Science.gov (United States)

    2016-10-01

    AWARD NUMBER: W81XWH-15-1-0368 TITLE: Understanding Microbial Sensing in Inflammatory Bowel Disease Using Click Chemistry PRINCIPAL...AND SUBTITLE with Click Chemistry : : Understanding Microbial Sensing in Inflammatory Bowel Disease with Click Chemistry Understanding Microbial...Sensing in Inflammatory Bowel Disease with Click Chemistry 5a. CONTRACT NUMBER Understanding Microbial Sensing in Inflammatory Bowel Disease Using Click

  13. Women and Film: A Resource Handbook.

    Science.gov (United States)

    Association of American Colleges, Washington, DC. Project on the Status and Education of Women.

    This resource handbook provides a summary of the media resources available concerning women. Emphasis is placed on some questions to consider in planning a film festival, suggestions for reducing costs, feature length films pertinent to women's roles, films shown at the first International Festival of Women's Films, short films, slide programs,…

  14. Elasticity of Flowing Soap films

    Science.gov (United States)

    Kim, Ildoo; Mandre, Shreyas

    2016-11-01

    The robustness of soap films and bubbles manifests their mechanical stability. The single most important factor underlying the mechanical stability of soap films is its elasticity. Non-destructive measurement of the elasticity in these films has been cumbersome, because of its flowing nature. Here we provide a convenient, reproducible, and non-destructive method for measuring the elasticity by generating and inspecting Marangoni waves. Our method is based on generating an oblique shock by inserting a thin cylindrical obstacle in the flowing film, and converting the measured the shock angle to elasticity. Using this method, we find a constant value for the elasticity of 22 dyne/cm in the commonly used range of film widths, thicknesses or flow rates, implying that the surface of the film is chemically saturated with soap molecules.

  15. Evaluation of microbial diversity of the microbial mat from the extremely acidic Lake Robule (Bor, Serbia)

    OpenAIRE

    Stanković Srđan; Vasiljević Branka; Jeremić Sanja; Cvetković Vladica; Morić Ivana

    2017-01-01

    Extremely acidic environments are frequently formed in areas impacted by mining activities, and Lake Robule is such an ecosystem. Although an extreme environment, Lake Robule is inhabited by acidophilic microorganisms. We investigated biodiversity of the macroscopic structure known as a microbial mat formed on the lake bottom in shallow waters. Microbial mats are common in acidic environments, but their composition can differ significantly from site to site. Microbial diversity of the mat fro...

  16. Microbial volatile fongerprints : potential use for soil / water diagnostics and correlation with traditional microbial parameters

    OpenAIRE

    Bastos, A.C.

    2007-01-01

    This project used an electronic nose (E-nose) system composed of an array of 14 non- specific conducting polymer sensors for soil and water diagnostics, based on qualitative microbial volatile production patterns. It tested the feasibility of using soil microbial volatile fingerprints for detecting and monitoring changes in microbial activity in three soils, as a response to key environmental factors such as temperature (16, 25, 37°C), water potential (-0.7, -2.8 MPa), and nutr...

  17. Performance evaluation of cassava starch-zinc nanocomposite film for tomatoes packaging

    Directory of Open Access Journals (Sweden)

    Adeshina Fadeyibi

    2017-05-01

    Full Text Available Biodegradable nanocomposite films are novel materials for food packaging because of their potential to extend the shelf life of food. In this research, the performance of cassava starch-zincnanocomposite film was evaluated for tomatoes packaging. The films were developed by casting the solutions of 24 g cassava starch, 0-2% (w/w zinc nanoparticles and 55% (w/w glycerol in plastic mould of 12 mm depth. The permeability of the films, due to water and oxygen, was investigated at 27°C and 65% relative humidity while the mechanical properties were determined by nanoindentation technique. The average thickness of the dried nanocomposite films was found to be 17±0.13 μm. The performances of films for tomatoes packaging was evaluated in comparison with low density polyethylene (LDPE; 10 μm at the temperature and period ranges of 10-27°C and 0-9 days, respectively. The quality and microbial attributes of the packaged tomatoes, including ascorbic acid, β-carotene and total coliform were analysed at an interval of 3 days. The results revealed that the water vapour permeability increased while the oxygen permeability decreased with the nanoparticles (P<0.05. The hardness, creep, elastic and plastic works, which determined the plasticity index of the film, decreased generally with the nanoparticles. The films containing 1 and 2% of the nanoparticles suppressed the growth of microorganisms and retained the quality of tomatoes than the LDPE at 27°C and day-9 of packaging (P<0.05. The results implied that the film could effectively be used for tomatoes packaging due to their lower oxygen permeability, hardness, elastic and plastic works.

  18. Development of Multifunctional Active Film and Its Application in Modified Atmosphere Packaging of Shiitake Mushrooms.

    Science.gov (United States)

    Wang, Hong Jiang; An, Duck Soon; Lee, Dong Sun

    2016-09-01

    Agar-based films with multiple functions (CO2 absorption, water vapor absorption, and antimicrobial activity) were developed, tested for their properties, and then applied to the packaging of fresh shiitake mushrooms as an insert label. The films were cast from an agar-based aqueous solution containing a dissolving plasticizer (glycerol), a CO2 absorbent (sodium carbonate [SC] alone or a combination of SC and sodium glycinate [SC-SG]), and a volatile antimicrobial agent (carvacrol [CRV]). The agar of the film matrix is designed to serve as a water vapor absorbent. The multifunctional films tended to have poor mechanical properties, with a hard texture and an opaque and yellowish color. The CO2 absorbent, either SC alone or SC-SG, affected CRV retention and release along with the CO2 and water vapor absorption behavior. Both films (SC-CRV and SC-SG-CRV films) showed good inhibitory effects against Pseudomonas fluorescens and Saccharomyces cerevisiae . SC-CRV film had a higher and faster CO2 absorption property, higher retention and extended release of CRV, and lower and slower water vapor absorption and was assessed to be better suited for use in shiitake mushroom packaging. The packaging in which the SC-CRV film with an appropriate amount of CRV was used as an insert label was able to generate the desired atmosphere and less moisture condensation inside the package, producing the best preservation of quality in terms of mushroom color, firmness, flavor score, and microbial counts after 6 days of storage at 10°C. A tailored modified atmosphere packaging system using multifunctional film would be useful in the preservation of CO2-sensitive fresh commodities.

  19. Development of chlorine dioxide releasing film and its application in decontaminating fresh produce.

    Science.gov (United States)

    Ray, Soumi; Jin, Tony; Fan, Xuetong; Liu, Linshu; Yam, Kit L

    2013-02-01

    A feasibility study was conducted to develop chlorine dioxide (ClO(2) )-releasing packaging films for decontaminating fresh produce. Sodium chlorite and citric acid powder were incorporated into polylactic acid (PLA) polymer. Films made with different amounts of PLA (100 and 300 mg), percentages of reactant (5% to 60%), and ratios of sodium chlorite to citric acid (1:2 or 2:1) were prepared using a solvent casting method. The release of ClO(2) from the resultant films was activated by moisture. Increase of reactants in the films produced more ClO(2) while higher PLA content in the films resulted in less release of ClO(2) . The ratio of sodium chlorite to citric acid and activation temperature (22 °C compared with 10 °C) did not affect the ClO(2) release from the films. Antimicrobial efficacy of ClO(2) released from the films was evaluated using grape tomato as a model food. The results indicate that the films were activated by moisture from tomatoes in the package and the released ClO(2) reduced Salmonella spp. and Escherichia coli O157:H7 inoculated on the tomatoes to undetectable levels (units (CFU)/tomato), achieving more than 3 log reduction. The film-treated tomatoes did not show significant changes in color and texture as compared to controls during storage at 10 °C for 21 d. This study demonstrated the technical feasibility for development of gaseous ClO(2) -releasing packaging system to enhance microbial safety and extend shelf life of fresh produce. © 2013 Institute of Food Technologists®

  20. Chitosan composite films. Biomedical applications.

    Science.gov (United States)

    Cárdenas, Galo; Anaya, Paola; von Plessing, Carlos; Rojas, Carlos; Sepúlveda, Jackeline

    2008-06-01

    Chitosan acetate films have been prepared using chitosans from shrimps (Pleuroncodes monodon) of low and high molecular weight (LMv = 68,000 g/mol and HMv = 232,000 g/mol) and deacetylation degree of 80 and 100%, respectively. The chitosan films were obtained by addition of several additives to acetic acid chitosan solutions, such as: glycerol, oleic acid and linoleic acid in different proportions. The pH of the solutions before casting ranged from 5.0 to 6.0. The composite film thickness are reported. The films have been analyzed by FTIR showing characteristic bands corresponding to the additives. The scanning electron microscopy (SEM) studies reveals the different morphology of the composite films. The films exhibit different physical properties depending upon the additives and/or mixture of them. The addition of glycerol to composite improves the elasticity of the films. The swelling in glucose and saline solutions for several films was evaluated, being higher in the glucose solution. The bactericide test against Staphylococcus aureus, Pseudomona aeruginosa and Acinetobacter baumanii in plates with either blood and or agar tripticase showed that the molecular weight influences on the bactericidal properties of the chitosan composite films and over its effect against gram positive and gram negative bacteria. Medical applications of the composite films were done in patients with burns, ulcers and injuries, the films containing glycerol showed good adhesion in comparison with those without it. The composite films tested were mainly three (1) chitosan acetate with glycerol, (2) chitosan acetate with oleic acid and (3) chitosan acetate with glycerol and oleic acid. Excellent results in the skin recovery were obtained after 7-10 days. Since the chitosan is biodegradable by the body enzymes it does not need to be removed and increases the gradual grows of the damage tissues.

  1. Conelike soap films spanning tetrahedra

    OpenAIRE

    Huff, Robert

    2008-01-01

    In this paper we provide the first examples of non-flat soap films proven to span tetrahedra. These are members of a continuous two parameter family of soap films with tetrahedral boundaries. Of particular interest is a two parameter subfamily where each spanning soap film has the property that two minimal surfaces meet along an edge of the boundary at an angle greater than 120 degrees.

  2. Use of edible films and coatings to extend the shelf life of food products.

    Science.gov (United States)

    Maftoonazad, Neda; Badii, Fojan

    2009-06-01

    The increased consumer demand for high quality, extended shelf life, ready to eat foods has initiated the development of several innovative techniques to keep their natural and fresh appearance as long as possible and at the same time render them safe. Packaging has been an important element in these preservation concepts for providing the appropriate (mechanical and functional) protection to the commodity. Since synthetic packaging materials contribute to the environmental pollution, edible coatings and packages have been proposed to replace or complement conventional packaging. Biodegradable and edible films and coatings are made from naturally occurring polymers and functional ingredients, and formed on the surface of food products. Edible films and coating have long been known to protect perishable food products from deterioration and reduce quality loss. These films should have acceptable sensory characteristics, appropriate barrier properties (CO(2), O(2), water, oil), microbial, biochemical and physicochemical stability, they should be safe, and be produced by simple technology in low cost. Also they can act as effective carrier for antioxidant, flavor, color, nutritional or anti-microbial additives. Patents on edible films and food products are also discussed in this article.

  3. Microbial heterogeneity affects bioprocess robustness: dynamic single-cell analysis contributes to understanding of microbial populations.

    Science.gov (United States)

    Delvigne, Frank; Goffin, Philippe

    2014-01-01

    Heterogeneity or segregation of microbial populations has been the subject of much research, but the real impact of this phenomenon on bioprocesses remains poorly understood. The main reason for this lack of knowledge is the difficulty in monitoring microbial population heterogeneity under dynamic process conditions. The main concepts resulting in microbial population heterogeneity in the context of bioprocesses have been summarized by two distinct hypotheses. The first involves the individual history of microbial cells or the "path" followed during their residence time inside the process equipment. The second hypothesis involves a coordinated response by the microbial population as a bet-hedging strategy, in order to cope with process-related stresses. The respective contribution of each hypothesis to microbial heterogeneity in bioprocesses is still unclear. This illustrates the fact that, although microbial phenotypic heterogeneity has been thoroughly investigated at a fundamental level, the implications of this phenomenon in the context of microbial bioprocesses are still subject to debate. At this time, automated flow cytometry is the best technique for investigating microbial heterogeneity under process conditions. However, dedicated software and relevant biomarkers are needed for the proper integration of flow cytometry as a bioprocess control tool. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. The interpretation of quantitative microbial data

    DEFF Research Database (Denmark)

    Ribeiro Duarte, Ana Sofia

    infection or disease due to ingestion of a specific pathogenic microorganism conveyed by specific food products; it is also used to assess the effect of different control measures. In their role of risk managers, public authorities base their policies on the outcome of risk assessmentstudies. Therefore......, they need to be transparent and affected by minimum imprecision. The potential exposure to and infection by foodborne microorganisms depend, among other factors, on the microbial concentrations in food and on the microbial behaviour (growth, survival and transfer) along the food chain. Both factors...... are therefore important inputs in QMRA. Since microbial concentrations vary among different samples of a food lot, probability distributions are used to describe these concentrations in QMRA. As microbial behaviour varies with food storage conditions (because it depends on intrinsic properties of food...

  5. Microbial (Pathogen)/Recreational Water Quality Criteria

    Science.gov (United States)

    Documents pertaining to Recreational Human Health Ambient Water Quality Criteria for Microbial Organisms (Pathogens). These documents include safe levels for cyanotoxins microcystin and cylindrospermopsin, and Coliphage to protect human health.

  6. Paleobiological Perspectives on Early Microbial Evolution.

    Science.gov (United States)

    Knoll, Andrew H

    2015-07-01

    Microfossils, stromatolites, and chemical biosignatures indicate that Earth became a biological planet more than 3.5 billion years ago, making most of life's history microbial. Proterozoic rocks preserve a rich record of cyanobacteria, including derived forms that differentiate multiple cell types. Stromatolites, in turn, show that microbial communities covered the seafloor from tidal flats to the base of the photic zone. The Archean record is more challenging to interpret, particularly on the question of cyanobacterial antiquity, which remains to be resolved. In the late Neoproterozoic Era, increasing oxygen and radiating eukaryotes altered the biosphere, with planktonic algae gaining ecological prominence in the water column, whereas seaweeds and, eventually, animals spread across shallow seafloors. From a microbial perspective, however, animals, algae, and, later, plants simply provided new opportunities for diversification, and, to this day, microbial metabolisms remain the only essential components of biogeochemical cycles. Copyright © 2015 Cold Spring Harbor Laboratory Press; all rights reserved.

  7. Discovering new bioactive molecules from microbial sources

    National Research Council Canada - National Science Library

    Monciardini, Paolo; Iorio, Marianna; Maffioli, Sonia; Sosio, Margherita; Donadio, Stefano

    2014-01-01

    ...‐resistant microbial pathogens. Natural products represent a major source of approved drugs and still play an important role in supplying chemical diversity, despite a decreased interest by large pharmaceutical companies...

  8. Oral chlorhexidine and microbial contamination during endoscopy

    DEFF Research Database (Denmark)

    Donatsky, Anders Meller; Holzknecht, Barbara Juliane; Arpi, Magnus

    2013-01-01

    BACKGROUND: One of the biggest concerns associated with transgastric surgery is contamination and risk of intra-abdominal infection with microbes introduced from the access route. The purpose of this study was to evaluate the effect of oral decontamination with chlorhexidine on microbial contamin......BACKGROUND: One of the biggest concerns associated with transgastric surgery is contamination and risk of intra-abdominal infection with microbes introduced from the access route. The purpose of this study was to evaluate the effect of oral decontamination with chlorhexidine on microbial...... contamination of the endoscope. METHODS: In a prospective, randomized, single-blinded, clinical trial the effect of chlorhexidine mouth rinse was evaluated. As a surrogate for the risk of intra-abdominal contamination during transgastric surgery, microbial contamination of the endoscope during upper endoscopy...... microbial contamination of the endoscope, but micro-organisms with abscess forming capabilities were still present. PPI treatment significantly increased CFU and should be discontinued before transgastric surgery....

  9. Predicting microbial nitrogen pathways from basic principles

    NARCIS (Netherlands)

    Leemput, van de I.A.; Veraart, A.J.; Dakos, V.; Klein, de J.J.M.; Strous, M.; Scheffer, M.

    2011-01-01

    Nitrogen compounds are transformed by a complicated network of competing geochemical processes or microbial pathways, each performed by a different ecological guild of microorganisms. Complete experimental unravelling of this network requires a prohibitive experimental effort. Here we present a

  10. Center for Advancing Microbial Risk Assessment

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for Advancing Microbial Risk Assessment (CAMRA), based at Michigan State University and jointly funded by the U.S. Department of Homeland Security and the...

  11. A thermodynamic theory of microbial growth

    Science.gov (United States)

    Desmond-Le Quéméner, Elie; Bouchez, Théodore

    2014-01-01

    Our ability to model the growth of microbes only relies on empirical laws, fundamentally restricting our understanding and predictive capacity in many environmental systems. In particular, the link between energy balances and growth dynamics is still not understood. Here we demonstrate a microbial growth equation relying on an explicit theoretical ground sustained by Boltzmann statistics, thus establishing a relationship between microbial growth rate and available energy. The validity of our equation was then questioned by analyzing the microbial isotopic fractionation phenomenon, which can be viewed as a kinetic consequence of the differences in energy contents of isotopic isomers used for growth. We illustrate how the associated theoretical predictions are actually consistent with recent experimental evidences. Our work links microbial population dynamics to the thermodynamic driving forces of the ecosystem, which opens the door to many biotechnological and ecological developments. PMID:24522260

  12. MICROBIAL BIOFILMS AS INDICATORS OF ESTUARINE CONDITION

    Science.gov (United States)

    Microbial biofilms are complex communities of bacteria, protozoa, microalgae, and micrometazoa which exist in a polymer matrix on submerged surfaces. Their development is integrative of environmental conditions and is affected by local biodiversity, the availability of organic ma...

  13. Exocellular electron transfer in anaerobic microbial communities

    NARCIS (Netherlands)

    Stams, A.J.M.; Bok, de F.A.M.; Plugge, C.M.; Eekert, van M.H.A.; Dolfing, J.; Schraa, G.

    2006-01-01

    Exocellular electron transfer plays an important role in anaerobic microbial communities that degrade organic matter. Interspecies hydrogen transfer between microorganisms is the driving force for complete biodegradation in methanogenic environments. Many organic compounds are degraded by obligatory

  14. Harnessing microbial resources for increased agricultural ...

    African Journals Online (AJOL)

    Mo

    depletion, environmental, agricultural, food, forestry and public health concerns and contributions towards poverty eradication and improved livelihoods of the people. ... status of microbial resource utilization and conservation has been recently reviewed ... Food Science and Technology Institute. (FOSRI). Pathogens.

  15. Ecological processes in groundwater microbial community assembly

    OpenAIRE

    Strack, Michael

    2015-01-01

    ~12 minute presentation from Macquarie University Department of Biological Sciences 2015 HDR Research Conference. Summarises a section of my PhD research on the evidence for community structuring by dispersal limitation and environmental selection in groundwater microbial ecosystems.

  16. Defining seasonal marine microbial community dynamics

    National Research Council Canada - National Science Library

    Gilbert, Jack A; Steele, Joshua A; Caporaso, J Gregory; Steinbrück, Lars; Reeder, Jens; Temperton, Ben; Huse, Susan; McHardy, Alice C; Knight, Rob; Joint, Ian; Somerfield, Paul; Fuhrman, Jed A; Field, Dawn

    Here we describe, the longest microbial time-series analyzed to date using high-resolution 16S rRNA tag pyrosequencing of samples taken monthly over 6 years at a temperate marine coastal site off Plymouth, UK...

  17. Incidente of microbial contaminants in sugarcane micropropagation

    Directory of Open Access Journals (Sweden)

    Yelenys Alvarado-Capó

    2003-01-01

    Full Text Available The incidence of microbial contaminants in Establishment, Multiplication and Rooting stages of the sugarcane micropropagation was determined by visual observation of the culture vessels. The type of microorganism was confirmed in observations to the optic microscope. The percentage of contamination for microbial group was determined in 731 apexes in the Establishment stage, in each multiplication subculture (up to the seventh in a total of 5 225 in vitro plants and 6 650 in the Rooting stage. In three stages the presence of microbial contaminants was verified (filamentous fungi, bacteria and yeasts with prevalence of the bacteria (13.7-31.6%. In the Multiplication stage the percentages of bacterial contamination were increased with the number of subcultures. The results indicated the high incidence of microbial contaminants in sugarcane micropropagation and the necessity of paying attention to the control of the bacterial contamination. Key words: bacteria, filamentous fungi, in vitro plants, yeast

  18. Monitoring microbial population dynamics at low densities

    Science.gov (United States)

    Julou, Thomas; Desprat, Nicolas; Bensimon, David; Croquette, Vincent

    2012-07-01

    We propose a new and simple method for the measurement of microbial concentrations in highly diluted cultures. This method is based on an analysis of the intensity fluctuations of light scattered by microbial cells under laser illumination. Two possible measurement strategies are identified and compared using simulations and measurements of the concentration of gold nanoparticles. Based on this comparison, we show that the concentration of Escherichia coli and Saccharomyces cerevisiae cultures can be easily measured in situ across a concentration range that spans five orders of magnitude. The lowest measurable concentration is three orders of magnitude (1000×) smaller than in current optical density measurements. We show further that this method can also be used to measure the concentration of fluorescent microbial cells. In practice, this new method is well suited to monitor the dynamics of population growth at early colonization of a liquid culture medium. The dynamic data thus obtained are particularly relevant for microbial ecology studies.

  19. Microbial cell surfaces and secretion systems

    NARCIS (Netherlands)

    Tommassen, J.P.M.|info:eu-repo/dai/nl/069127077; Wosten, H.A.B.|info:eu-repo/dai/nl/120693186

    2015-01-01

    Microbial cell surfaces, surface-exposed organelles, and secreted proteins are important for the interaction with the environment, including adhesion to hosts, protection against host defense mechanisms, nutrient acquisition, and intermicrobial competition. Here, we describe the structures of the

  20. Microbial interactions in building of communities

    Science.gov (United States)

    Wright, Christopher J.; Burns, Logan H.; Jack, Alison A.; Back, Catherine R.; Dutton, Lindsay C.; Nobbs, Angela H.; Lamont, Richard J.; Jenkinson, Howard F.

    2012-01-01

    SUMMARY Establishment of a community is considered to be essential for microbial growth and survival in the human oral cavity. Biofilm communities have increased resilience to physical forces, antimicrobial agents, and nutritional variations. Specific cell-to-cell adherence processes, mediated by adhesin-receptor pairings on respective microbial surfaces, are able to direct community development. These interactions co-localize species in mutually beneficial relationships, such as streptococci, veillonellae, Porphyromonas gingivalis and Candida albicans. In transition from the planktonic mode of growth to a biofilm community, microorganisms undergo major transcriptional and proteomic changes. These occur in response to sensing of diffusible signals, such as autoinducer molecules, and to contact with host tissues or other microbial cells. Underpinning many of these processes are intracellular phosphorylation events that regulate a large number of microbial interactions relevant to community formation and development. PMID:23253299

  1. Guiding bioprocess design by microbial ecology.

    Science.gov (United States)

    Volmer, Jan; Schmid, Andreas; Bühler, Bruno

    2015-06-01

    Industrial bioprocess development is driven by profitability and eco-efficiency. It profits from an early stage definition of process and biocatalyst design objectives. Microbial bioprocess environments can be considered as synthetic technical microbial ecosystems. Natural systems follow Darwinian evolution principles aiming at survival and reproduction. Technical systems objectives are eco-efficiency, productivity, and profitable production. Deciphering technical microbial ecology reveals differences and similarities of natural and technical systems objectives, which are discussed in this review in view of biocatalyst and process design and engineering strategies. Strategies for handling opposing objectives of natural and technical systems and for exploiting and engineering natural properties of microorganisms for technical systems are reviewed based on examples. This illustrates the relevance of considering microbial ecology for bioprocess design and the potential for exploitation by synthetic biology strategies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. Cheese Microbial Risk Assessments ? A Review

    OpenAIRE

    Kyoung-Hee Choi; Heeyoung Lee; Soomin Lee; Sejeong Kim; Yohan Yoon

    2016-01-01

    Cheese is generally considered a safe and nutritious food, but foodborne illnesses linked to cheese consumption have occurred in many countries. Several microbial risk assessments related to Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli infections, causing cheese-related foodborne illnesses, have been conducted. Although the assessments of microbial risk in soft and low moisture cheeses such as semi-hard and hard cheeses have been accomplished, it has been more focused o...

  3. Biofilm and dental implant: The microbial link

    OpenAIRE

    Dhir, Sangeeta

    2013-01-01

    Mouth provides a congenial environment for the growth of the microorganisms as compared to any other part of the human body by exhibiting an ideal nonshedding surface. Dental plaque happens to be a diverse community of the microorganisms found on the tooth surface. Periodontal disease and the peri-implant disease are specific infections that are originating from these resident microbial species when the balance between the host and the microbial pathogenicity gets disrupted. This review discu...

  4. A family of microbial lysine transporter polypeptides

    DEFF Research Database (Denmark)

    2017-01-01

    modifications that confer reduced lysine metabolism and/or enhanced lysine synthesis as compared to the parent cell from which said genetically modified cell was derived. The invention further provides a method for producing lysine using the genetically modified microbial cell. The invention further provides...... a novel family of lysine transporter polypeptides; and the use of said polypeptide to enhance production of extracellular lysine in a microbial cell....

  5. Microbial Biofilm as a Smart Material

    OpenAIRE

    Christian Garde; Martin Welch; Jesper Ferkinghoff-Borg; Thomas Sams

    2015-01-01

    Microbial biofilm colonies will in many cases form a smart material capable of responding to external threats dependent on their size and internal state. The microbial community accordingly switches between passive, protective, or attack modes of action. In order to decide which strategy to employ, it is essential for the biofilm community to be able to sense its own size. The sensor designed to perform this task is termed a quorum sensor, since it only permits collective behaviour once a suf...

  6. Patterns and Scales in Gastrointestinal Microbial Ecology

    OpenAIRE

    Camp, J. Gray; Kanther, Michelle; Semova, Ivana; Rawls, John F.

    2009-01-01

    The body surfaces of humans and other animals are colonized at birth by microorganisms. The majority of microbial residents on the human body exist within gastrointestinal (GI) tract communities, where they contribute to many aspects of host biology and pathobiology. Recent technological advances have expanded our ability to perceive the membership and physiologic traits of microbial communities along the GI tract. To translate this information into a mechanistic and practical understanding o...

  7. Microbial Life in a Liquid Asphalt Desert

    OpenAIRE

    Schulze-Makuch, Dirk; Haque, Shirin; Antonio, Marina Resendes de Sousa; Ali, Denzil; Hosein, Riad; Song, Young C.; Yang, Jinshu; Zaikova, Elena; Beckles, Denise M.; Guinan, Edward; Lehto, Harry J.; Hallam, Steven J.

    2010-01-01

    An active microbiota, reaching up to 10 E+7 cells/g, was found to inhabit a naturally occurring asphalt lake characterized by low water activity and elevated temperature. Geochemical and molecular taxonomic approaches revealed novel and deeply branching microbial assemblages mediating anaerobic hydrocarbon degradation, metal respiration and C1 utilization pathways. These results open a window into the origin and adaptive evolution of microbial life within recalcitrant hydrocarbon matrices, an...

  8. Microbial keratitis in West and East Malaysia

    OpenAIRE

    Vanitha Ratnalingam; Thiageswari Umapathy; Kala Sumugam; Hanida Hanafi; Shamala Retnasabapathy

    2017-01-01

    AIM: To evaluate the epidemiological and etiological factors of microbial keratitis seen in tertiary hospitals in West and East Malaysia.METHODS: A total of 207 patients were enrolled. Patients referred for microbial keratitis to Sungai Buloh Hospital and Kuala Lumpur Hospital in West Malaysia and Queen Elizabeth Hospital and Kuching General Hospital in East Malaysia were recruited. Risk factors were documented. Corneal scrapings for microscopy and culture were performed.RESULTS: The most com...

  9. Nanofibrillated Cellulose and Copper Nanoparticles Embedded in Polyvinyl Alcohol Films for Antimicrobial Applications

    Science.gov (United States)

    Zhong, Tuhua; Oporto, Gloria S.; Jaczynski, Jacek; Jiang, Changle

    2015-01-01

    Our long-term goal is to develop a hybrid cellulose-copper nanoparticle material as a functional nanofiller to be incorporated in thermoplastic resins for efficiently improving their antimicrobial properties. In this study, copper nanoparticles were first synthesized through chemical reduction of cupric ions on TEMPO nanofibrillated cellulose (TNFC) template using borohydride as a copper reducing agent. The resulting hybrid material was embedded into a polyvinyl alcohol (PVA) matrix using a solvent casting method. The morphology of TNFC-copper nanoparticles was analyzed by transmission electron microscopy (TEM); spherical copper nanoparticles with average size of 9.2 ± 2.0 nm were determined. Thermogravimetric analysis and antimicrobial performance of the films were evaluated. Slight variations in thermal properties between the nanocomposite films and PVA resin were observed. Antimicrobial analysis demonstrated that one-week exposure of nonpathogenic Escherichia coli DH5α to the nanocomposite films results in up to 5-log microbial reduction. PMID:26137482

  10. Potential of nisin-incorporated sodium caseinate films to control Listeria in artificially contaminated cheese.

    Science.gov (United States)

    Cao-Hoang, Lan; Chaine, Aline; Grégoire, Lydie; Waché, Yves

    2010-10-01

    A sodium caseinate film containing nisin (1000 IU/cm(2)) was produced and used to control Listeria innocua in an artificially contaminated cheese. Mini red Babybel cheese was chosen as a model semi-soft cheese. L. innocua was both surface- and in-depth inoculated to investigate the effectiveness of the antimicrobial film as a function of the distance from the surface in contact with the film. The presence of the active film resulted in a 1.1 log CFU/g reduction in L. innocua counts in surface-inoculated cheese samples after one week of storage at 4 degrees C as compared to control samples. With regard to in-depth inoculated cheese samples, antimicrobial efficiency was found to be dependent on the distance from the surface in contact with the active films to the cheese matrix. The inactivation rates obtained were 1.1, 0.9 and 0.25 log CFU/g for distances from the contact surface of 1 mm, 2 mm and 3 mm, respectively. Our study demonstrates the potential application of sodium caseinate films containing nisin as a promising method to overcome problems associated with post-process contamination, thereby extending the shelf life and possibly enhancing the microbial safety of cheeses. 2010 Elsevier Ltd. All rights reserved.

  11. Characteristic of ascorbic acid in crosslinked chitosan edible film as drug delivery system membrane

    Directory of Open Access Journals (Sweden)

    Kistriyani Lilis

    2018-01-01

    Full Text Available Chitosan is a polysaccharide compound in the form of a linear polysaccharide consisting of N-acetyl glucosamine (GlcNAc and D-glucosamine (GlcN monomer, which is a derivative of deacetylization of chitin polymer. Chitin is one of common type of polysaccharide on earth after the excess cellulose from inveterbrata skeletons. Chitosan has anti-microbial properties. Based on this properties, chitosan is potentially used to be an edible film as drug delivery system membrane. Edible film was made by dissolving chitosan in 100 mL acetic acid 1%, then the plasticizer and crosslinker was added while heated at 60° C. It was molded and dried in oven at 50°C for 48 hours. Drug loading in the edible film could be controlled by remodeling membrane characteristics in the presence of crosslinker additions. The purpose of this study was to estimate the mass transfer coefficient (kCa of drug loading in various concentrations of ascorbic acid in the edible film. The characteristics of ascorbic acid in chitosan edible film could be seen from the number of drugs that could be loaded through the uv-vis spectrophotometric analysis. The higher concentration of ascorbic acid was added, the drug would be loaded more into edible film.

  12. Degradation of biodegradable plastic mulch films in soil environment by phylloplane fungi isolated from gramineous plants.

    Science.gov (United States)

    Koitabashi, Motoo; Noguchi, Masako T; Sameshima-Yamashita, Yuka; Hiradate, Syuntaro; Suzuki, Ken; Yoshida, Shigenobu; Watanabe, Takashi; Shinozaki, Yukiko; Tsushima, Seiya; Kitamoto, Hiroko K

    2012-08-02

    To improve the biodegradation of biodegradable plastic (BP) mulch films, 1227 fungal strains were isolated from plant surface (phylloplane) and evaluated for BP-degrading ability. Among them, B47-9 a strain isolated from the leaf surface of barley showed the strongest ability to degrade poly-(butylene succinate-co-butylene adipate) (PBSA) and poly-(butylene succinate) (PBS) films. The strain grew on the surface of soil-mounted BP films, produced breaks along the direction of hyphal growth indicated that it secreted a BP-degrading enzyme, and has directly contributing to accelerating the degradation of film. Treatment with the culture filtrate decomposed 91.2 wt%, 23.7 wt%, and 14.6 wt% of PBSA, PBS, and commercially available BP polymer blended mulch film, respectively, on unsterlized soil within 6 days. The PCR-DGGE analysis of the transition of soil microbial community during film degradation revealed that the process was accompanied with drastic changes in the population of soil fungi and Acantamoeba spp., as well as the growth of inoculated strain B47-9. It has a potential for application in the development of an effective method for accelerating degradation of used plastics under actual field conditions.

  13. Physicochemical properties of apple puree-alginate films containing plant essential oils and oil compounds active against Escherichia coli 0157:H7

    Science.gov (United States)

    The use of edible films as carriers of antimicrobial plant essential oils and other phytochemicals constitutes an approach for external protection of food systems to reduce surface microbial populations and to enhance oxygen-barrier properties, thus enhancing food safety as well as shelf life. To de...

  14. Sophorolipid-induced dimpling and increased porosity in solvent-cast short-chain polyhydroxyalkanoate films: impact on thermo-mechanical properties

    Science.gov (United States)

    Sophorolipids (SL; microbial glycolipids) were used as additives in solvent-cast short-chain polyhydroxyalkanoate (sc-PHA) films to enhance surface roughness and porosity. Poly-3-hydroxybutyrate (PHB), poly-(6%)-3-hydroxybutyrate-co-(94%)-3-hydroxyvalerate (PHB/V), and poly-(90%)-3-hydroxybutyrate-c...

  15. Cheese Microbial Risk Assessments — A Review

    Directory of Open Access Journals (Sweden)

    Kyoung-Hee Choi

    2016-03-01

    Full Text Available Cheese is generally considered a safe and nutritious food, but foodborne illnesses linked to cheese consumption have occurred in many countries. Several microbial risk assessments related to Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli infections, causing cheese-related foodborne illnesses, have been conducted. Although the assessments of microbial risk in soft and low moisture cheeses such as semi-hard and hard cheeses have been accomplished, it has been more focused on the correlations between pathogenic bacteria and soft cheese, because cheese-associated foodborne illnesses have been attributed to the consumption of soft cheeses. As a part of this microbial risk assessment, predictive models have been developed to describe the relationship between several factors (pH, Aw, starter culture, and time and the fates of foodborne pathogens in cheese. Predictions from these studies have been used for microbial risk assessment as a part of exposure assessment. These microbial risk assessments have identified that risk increased in cheese with high moisture content, especially for raw milk cheese, but the risk can be reduced by preharvest and postharvest preventions. For accurate quantitative microbial risk assessment, more data including interventions such as curd cooking conditions (temperature and time and ripening period should be available for predictive models developed with cheese, cheese consumption amounts and cheese intake frequency data as well as more dose-response models.

  16. Cheese Microbial Risk Assessments — A Review

    Science.gov (United States)

    Choi, Kyoung-Hee; Lee, Heeyoung; Lee, Soomin; Kim, Sejeong; Yoon, Yohan

    2016-01-01

    Cheese is generally considered a safe and nutritious food, but foodborne illnesses linked to cheese consumption have occurred in many countries. Several microbial risk assessments related to Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli infections, causing cheese-related foodborne illnesses, have been conducted. Although the assessments of microbial risk in soft and low moisture cheeses such as semi-hard and hard cheeses have been accomplished, it has been more focused on the correlations between pathogenic bacteria and soft cheese, because cheese-associated foodborne illnesses have been attributed to the consumption of soft cheeses. As a part of this microbial risk assessment, predictive models have been developed to describe the relationship between several factors (pH, Aw, starter culture, and time) and the fates of foodborne pathogens in cheese. Predictions from these studies have been used for microbial risk assessment as a part of exposure assessment. These microbial risk assessments have identified that risk increased in cheese with high moisture content, especially for raw milk cheese, but the risk can be reduced by preharvest and postharvest preventions. For accurate quantitative microbial risk assessment, more data including interventions such as curd cooking conditions (temperature and time) and ripening period should be available for predictive models developed with cheese, cheese consumption amounts and cheese intake frequency data as well as more dose-response models. PMID:26950859

  17. Microbial changes during pregnancy, birth and infancy

    Directory of Open Access Journals (Sweden)

    Meital Nuriel-Ohayon

    2016-07-01

    Full Text Available Several healthy developmental processes such as pregnancy, fetal development and infant development include a multitude of physiological changes: weight gain, hormonal and metabolic changes, as well as immune changes. In this review we present an additional important factor which both influences and is affected by these physiological processes- the microbiome. We summarize the known changes in microbiota composition at a variety of body sites including gut, vagina, oral cavity and placenta, throughout pregnancy, fetal development and early childhood. There is still a lot to be discovered; yet several pieces of research point to the healthy desired microbial changes. Future research is likely to unravel precise roles and mechanisms of the microbiota in gestation; perhaps linking the metabolic, hormonal and immune changes together. Although some research has started to link microbial dysbiosis and specific microbial populations with unhealthy pregnancy complications, it is important to first understand the context of the natural healthy microbial changes occurring. Until recently the placenta and developing fetus were considered to be germ free, containing no apparent microbiome. We present multiple study results showing distinct microbiota compositions in the placenta and meconium, alluding to early microbial colonization. These results may change dogmas and our overall understanding of the importance and roles of microbiota from the beginning of life. We further review the main factors shaping the infant microbiome- modes of delivery, feeding, weaning, and exposure to antibiotics. Taken together, we are starting to build a broader understanding of healthy vs. abnormal microbial alterations throughout major developmental time-points.

  18. An Economic Framework of Microbial Trade.

    Directory of Open Access Journals (Sweden)

    Joshua Tasoff

    Full Text Available A large fraction of microbial life on earth exists in complex communities where metabolic exchange is vital. Microbes trade essential resources to promote their own growth in an analogous way to countries that exchange goods in modern economic markets. Inspired by these similarities, we developed a framework based on general equilibrium theory (GET from economics to predict the population dynamics of trading microbial communities. Our biotic GET (BGET model provides an a priori theory of the growth benefits of microbial trade, yielding several novel insights relevant to understanding microbial ecology and engineering synthetic communities. We find that the economic concept of comparative advantage is a necessary condition for mutualistic trade. Our model suggests that microbial communities can grow faster when species are unable to produce essential resources that are obtained through trade, thereby promoting metabolic specialization and increased intercellular exchange. Furthermore, we find that species engaged in trade exhibit a fundamental tradeoff between growth rate and relative population abundance, and that different environments that put greater pressure on group selection versus individual selection will promote varying strategies along this growth-abundance spectrum. We experimentally tested this tradeoff using a synthetic consortium of Escherichia coli cells and found the results match the predictions of the model. This framework provides a foundation to study natural and engineered microbial communities through a new lens based on economic theories developed over the past century.

  19. Microbial cellulose utilization: fundamentals and biotechnology.

    Science.gov (United States)

    Lynd, Lee R; Weimer, Paul J; van Zyl, Willem H; Pretorius, Isak S

    2002-09-01

    Fundamental features of microbial cellulose utilization are examined at successively higher levels of aggregation encompassing the structure and composition of cellulosic biomass, taxonomic diversity, cellulase enzyme systems, molecular biology of cellulase enzymes, physiology of cellulolytic microorganisms, ecological aspects of cellulase-degrading communities, and rate-limiting factors in nature. The methodological basis for studying microbial cellulose utilization is considered relative to quantification of cells and enzymes in the presence of solid substrates as well as apparatus and analysis for cellulose-grown continuous cultures. Quantitative description of cellulose hydrolysis is addressed with respect to adsorption of cellulase enzymes, rates of enzymatic hydrolysis, bioenergetics of microbial cellulose utilization, kinetics of microbial cellulose utilization, and contrasting features compared to soluble substrate kinetics. A biological perspective on processing cellulosic biomass is presented, including features of pretreated substrates and alternative process configurations. Organism development is considered for "consolidated bioprocessing" (CBP), in which the production of cellulolytic enzymes, hydrolysis of biomass, and fermentation of resulting sugars to desired products occur in one step. Two organism development strategies for CBP are examined: (i) improve product yield and tolerance in microorganisms able to utilize cellulose, or (ii) express a heterologous system for cellulose hydrolysis and utilization in microorganisms that exhibit high product yield and tolerance. A concluding discussion identifies unresolved issues pertaining to microbial cellulose utilization, suggests approaches by which such issues might be resolved, and contrasts a microbially oriented cellulose hydrolysis paradigm to the more conventional enzymatically oriented paradigm in both fundamental and applied contexts.

  20. Microbial Changes during Pregnancy, Birth, and Infancy.

    Science.gov (United States)

    Nuriel-Ohayon, Meital; Neuman, Hadar; Koren, Omry

    2016-01-01

    Several healthy developmental processes such as pregnancy, fetal development, and infant development include a multitude of physiological changes: weight gain, hormonal, and metabolic changes, as well as immune changes. In this review, we present an additional important factor which both influences and is affected by these physiological processes-the microbiome. We summarize the known changes in microbiota composition at a variety of body sites including gut, vagina, oral cavity, and placenta, throughout pregnancy, fetal development, and early childhood. There is still a lot to be discovered; yet several pieces of research point to the healthy desired microbial changes. Future research is likely to unravel precise roles and mechanisms of the microbiota in gestation; perhaps linking the metabolic, hormonal, and immune changes together. Although some research has started to link microbial dysbiosis and specific microbial populations with unhealthy pregnancy complications, it is important to first understand the context of the natural healthy microbial changes occurring. Until recently the placenta and developing fetus were considered to be germ free, containing no apparent microbiome. We present multiple study results showing distinct microbiota compositions in the placenta and meconium, alluding to early microbial colonization. These results may change dogmas and our overall understanding of the importance and roles of microbiota from the beginning of life. We further review the main factors shaping the infant microbiome-modes of delivery, feeding, weaning, and exposure to antibiotics. Taken together, we are starting to build a broader understanding of healthy vs. abnormal microbial alterations throughout major developmental time-points.

  1. An Economic Framework of Microbial Trade.

    Science.gov (United States)

    Tasoff, Joshua; Mee, Michael T; Wang, Harris H

    2015-01-01

    A large fraction of microbial life on earth exists in complex communities where metabolic exchange is vital. Microbes trade essential resources to promote their own growth in an analogous way to countries that exchange goods in modern economic markets. Inspired by these similarities, we developed a framework based on general equilibrium theory (GET) from economics to predict the population dynamics of trading microbial communities. Our biotic GET (BGET) model provides an a priori theory of the growth benefits of microbial trade, yielding several novel insights relevant to understanding microbial ecology and engineering synthetic communities. We find that the economic concept of comparative advantage is a necessary condition for mutualistic trade. Our model suggests that microbial communities can grow faster when species are unable to produce essential resources that are obtained through trade, thereby promoting metabolic specialization and increased intercellular exchange. Furthermore, we find that species engaged in trade exhibit a fundamental tradeoff between growth rate and relative population abundance, and that different environments that put greater pressure on group selection versus individual selection will promote varying strategies along this growth-abundance spectrum. We experimentally tested this tradeoff using a synthetic consortium of Escherichia coli cells and found the results match the predictions of the model. This framework provides a foundation to study natural and engineered microbial communities through a new lens based on economic theories developed over the past century.

  2. Microbial effects on colloidal agglomeration

    Energy Technology Data Exchange (ETDEWEB)

    Hersman, L.

    1995-11-01

    Colloidal particles are known to enhance the transport of radioactive metals through soil and rock systems. This study was performed to determine if a soil microorganism, isolated from the surface samples collected at Yucca Mountain, NV, could affect the colloidal properties of day particles. The agglomeration of a Wyoming bentonite clay in a sterile uninoculated microbial growth medium was compared to the agglomeration in the medium inoculated with a Pseudomonas sp. In a second experiment, microorganisms were cultured in the succinate medium for 50 h and removed by centrifugation. The agglomeration of the clay in this spent was compared to sterile uninoculated medium. In both experiments, the agglomeration of the clay was greater than that of the sterile, uninoculated control. Based on these results, which indicate that this microorganism enhanced the agglomeration of the bentonite clay, it is possible to say that in the presence of microorganisms colloidal movement through a rock matrix could be reduced because of an overall increase in the size of colloidal particle agglomerates. 32 refs.

  3. Tetranucleotide frequencies in microbial genomes.

    Science.gov (United States)

    Noble, P A; Citek, R W; Ogunseitan, O A

    1998-04-01

    A computational strategy for determining the variability of long DNA sequences in microbial genomes is described. Composite portraits of bacterial genomes were obtained by computing tetranucleotide frequencies of sections of genomic DNA, converting the frequencies to color images and arranging the images according to their genetic position. The resulting images revealed that the tetranucleotide frequencies of genomic DNA sequences are highly conserved. Sections that were visibly different from those of the rest of the genome contained ribosomal RNA, bacteriophage, or undefined coding regions and had corresponding differences in the variances of tetranucleotide frequencies and GC content. Comparison of nine completely sequenced bacterial genomes showed that there was a nonlinear relationship between variances of the tetranucleotide frequencies and GC content, with the highest variances occurring in DNA sequences with low GC contents (less than 0.30 mol). High variances were also observed in DNA sequences having high GC contents (greater than 0.60 mol), but to a much lesser extent than DNA sequences having low GC contents. Differences in the tetranucleotide frequencies may be due to the mechanisms of intercellular genetic exchange and/or processes involved in maintaining intracellular genetic stability. Identification of sections that were different from those of the rest of the genome may provide information on the evolution and plasticity of bacterial genomes.

  4. Microbial contamination in industrial tofu

    Directory of Open Access Journals (Sweden)

    Thaís Teresa Brandão Cavalheiro Ribeiro

    Full Text Available ABSTRACT: This study aimed to evaluate the microbiological quality of tofu sold in supermarkets in Porto Alegre/Brazil. Bacteria counts were performed for Bacillus cereus , mesophilic, coliforms and Staphylococcus coagulase positive and negative. The presence of Listeria sp. was also evaluated. Two different brands of tofu (A and B were collected, one lot per month, for six months. Five samples from each lot were analyzed. All lots presented mesophilic aerobic counts above 4.3x105CFU g-1. Four of the six lots from brand A and all lots from brand B showed E. coli and/or Staphylococcus coagulase positive counts above the Brazilian law accepted limits. The Staphylococcus coagulase negative counts were higher than those of coagulase positive in all lots. In all lots where Staphylococcus coagulase positive counts were above the legal limit, there were counts of coagulase negative above 104CFU g-1. B. cereus and Listeria sp. were not found in either brand. The majority of lots of brand A and all lots of brand B were unsuitable for human consumption. Our results showed that there are problems in tofu manufacturing in both industries analyzed. There is a need of improvement on its microbial quality to avoid problems of food-borne illness, and finally the need of a better control by the Brazilian inspection services.

  5. Halitosis: An oral microbial faction

    Directory of Open Access Journals (Sweden)

    Rajiv Saini

    2010-01-01

    Full Text Available Halitosis is a widespread condition and believed to affect one-quarter of the population around the world; also, most people have this condition from time to time. Breath malodour may be an important factor in social communication, and therefore may be the origin of concern not only for a possible health condition but also for frequent psychological alterations, leading to social and personal isolation. The most conspicuous malodorous compounds are termed volatile sulphur compounds (VSCs, with hydrogen sulphide, methyl mercaptan, and dimethyl sulphide accounting for roughly 90% of the VSCs. A number of oral bacteria, especially Gram-negative anaerobic species found in the subgingival plaque, produce a diverse array of malodorous compounds as byproducts of their metabolism, including VSCs and short-chain organic acids. Assessment and management of halitosis is of paramount importance in enhancing the overall health; moreover, dentists play a significant role in combating halitosis by reducing the oral microbial stack. Thus, the aim of the present review was to describe the aetiological factors, assessment tools, and therapeutic approaches related to halitosis.

  6. Comprehensive review on application of edible film on meat and meat products: An eco-friendly approach.

    Science.gov (United States)

    Umaraw, Pramila; Verma, Akhilesh K

    2017-04-13

    The functions of packaging materials are to prevent moisture loss, drip, reduce lipid oxidation, improve some of their sensorial properties (color, taste and smell) and provide microbial stability of foods. Edible films can be made from protein, polysaccharides and lipids or by combination of any of these to form a composite film. Nanocomposites are composite films made by incorporation of nanoparticles. Edible packaging and coating of the meat and meat products enhances the self-life by the incorporation of the active compound (such as antimicrobial and antioxidant compound) in to the packaging matrix. Incorporation of the some ingredients in the matrix may also improve the nutritional as well as sensory attributes of the packed products. Edible packaging material also reduces environmental pollution by overcoming the burden degradation as edible films are biodegradable and thus eco-friendly.

  7. "Kuleshov on Film": A Spectator-Centered Film Theory.

    Science.gov (United States)

    Curran, Trisha

    This paper describes some of the theories of cinematography of Soviet film theorist and filmmaker Lev Kuleshov. It points out that for him, film was communication portraying people's activities emanating from the environment. It explains that he was especially interested in audience response, particularly that of the proletariat, and that he felt…

  8. Obsolescence and Film Restoration: The case of Colored Silent Films

    NARCIS (Netherlands)

    Fossati, G.

    2013-01-01

    Elsewhere I have discussed the transitional nature of film and argued that the current shift from analog to digital technology is one of the many transitional phases that film has experienced in its history as a technology, a popular form of entertainment and art. The obsolescence brought about by

  9. Antioxidant, Color and Antibacterial Properties of Edible Chitosan Film Incorporated with Zataria Multiflora Boiss ٍEssential Oil against Listeria Monocytogenes

    Directory of Open Access Journals (Sweden)

    M Moradi

    2011-01-01

    Full Text Available Introduction & Objective: The film containing antimicrobial agents are a type of active packaging which is mainly designed to control microbial and chemical spoilage of food. The aim of this study was to evaluate the antimicrobial, antioxidant and color properties of chitosan film incorporated with essential oil of Zataria multiflora Boiss. (ZEO. Materials & Methods: In this experimental study which was conducted at Urmia University of Medical Sciences between 2009-2010, the chemical composition of ZEO was analyzed using GC-MS. Chitosan films containing 0, 0.5, 1 and 2% ZEO, were obtained by casting method and subsequently, total phenol (TP, antioxidant, color (accordance with hunter system (L* (luminosity, * (redness, and b* (yellowness and antimicrobial characteristics of films on Listeria monocytogenes were studied. The collected data was analyzed by the SPSS software. Results: The order of TP for all films in the experiment was 2% ZEO1% ZEO 0.5% ZEO unsupplemented chitosan film, respectively. It was also concluded that the antioxidant activity of chitosan films was increased by adding various concentrations of ZEO. These increases were significant for film containing 1% (33.98% and 2% (37.77% ZEO (p0.05. Regarding the color luminosity (L* of the chitosan film, results indicated no significant changes by incorporating ZEO, whereas the incorporation of ZEO into films had a significant effect on film yellowness, evidenced by lower b* values. Finally, it was shown that the presence of ZEO in chitosan films significantly modified the anti- listerial activity of chitosan, (p0.05. Conclusion: The results indicated that an active film from chitosan could be achieved by incorporating ZEO. Addition of ZEO improves functional and antibacterial characteristics of chitosan film.

  10. Falling Liquid Films

    CERN Document Server

    Kalliadasis, S; Scheid, B

    2012-01-01

    This research monograph gives a detailed review of the state-of-the-art theoretical methodologies for the analysis of dissipative wave dynamics and pattern formation on the surface of a film falling down a planar, inclined substrate. This prototype is an open-flow hydrodynamic instability representing an excellent paradigm for the study of complexity in active nonlinear media with energy supply, dissipation and dispersion. Whenever possible, the link between theory and experiments is illustrated and the development of order-of-magnitude estimates and scaling arguments is used to facilitate the

  11. History, Memory and Film

    DEFF Research Database (Denmark)

    Bondebjerg, Ib

    In this paper I discuss history and memory from a theoretical and philosophical point of view and the non-fiction and fiction aspects of historical representation. I use Edgar Reitz’ monumental work Heimat 1-3 (and his recent film Die Andere Heimat) as examples of very different transformative...... historical narratives. In terms of narrative construction and aesthetic form the Heimat-project challenges the dominant forms of historical fiction. By combining personal memory, everyday life and collective memory and a more indirect way of representing factual history Reitz wants to transform our look...

  12. Effect of edible chitosan/clove oil films and high-pressure processing on the microbiological shelf life of trout fillets.

    Science.gov (United States)

    Albertos, Irene; Rico, Daniel; Diez, Ana María; González-Arnáiz, Lucía; García-Casas, María Jesús; Jaime, Isabel

    2015-11-01

    The inhibitory effect of chitosan films with clove oil (0-50 g kg(-1) ) was evaluated on a range of ten representative food spoilage and pathogenic bacteria. The most sensitive bacteria to the films was Shewanella putrefaciens and the most resistant was Aeromonas hydrophila (inhibition was apparent only at 50 g kg(-1) clove essential oil (CEO)). Films with 20 g kg(-1) CEO inhibited nine of ten of the bacteria tested. Chitosan films with 20 g kg(-1) CEO were combined with high-pressure (HPP) processing as treatments for trout fillets, and changes in physicochemical parameters and microbial load were evaluated at 4 °C over 22 days of storage. The films reduced weight loss and water activity compared to fresh and treated samples (HPP and cooking). Results showed that microbial load (total aerobic mesophilic, lactic acid bacteria and total coliform) of the trout fillets covered with chitosan films was lower than that for HPP-treated samples, and similar to cooked samples, except for coliform counts. The use of 20 g kg(-1) CEO-chitosan films showed a further improvement in the shelf-life of trout fillets when compared to that obtained with HPP and cooking treatment. © 2014 Society of Chemical Industry.

  13. Listeria monocytogenes inhibition by defatted mustard meal-based edible films.

    Science.gov (United States)

    Lee, Hahn-Bit; Noh, Bong Soo; Min, Sea C

    2012-02-01

    An antimicrobial edible film was developed from defatted mustard meal (Sinapis alba) (DMM), a byproduct from the bio-fuel industry, without incorporating external antimicrobials and its antimicrobial activity against Listeria monocytogenes and physical properties were investigated. The DMM colloidal solution consisting of 184 g water, 14 g DMM, and 2g glycerol was homogenized and incubated at 37°C for 0.2, 0.5, 24 or 48 h to prepare a film-forming solution. The pH of a portion of the film-forming solution (pH 5.5) was adjusted to 2.0 or 4.0. Films were formed by drying the film-forming solutions at 23°C for 48 h. The film-forming solution incubated for 48 h inhibited L. monocytogenes in broth and on agar media. Antimicrobial effects of the film prepared from the 48 h-incubated solution increased with decrease in pH of the solution from 5.5 to 2.0. The film from the film forming solution incubated for 48 h (pH 2.0) initially inhibited more than 4.0 log CFU/g of L. monocytogenes inoculated on film-coated salmon. The film-coating retarded the growth of L. monocytogenes in smoked salmon at 5, 10, and 15°C and the antimicrobial effect during storage was more noticeable when the coating was applied before inoculation than when it was applied after inoculation. The tensile strength, percentage elongation, solubility in watercxu, and water vapor permeability of the anti microbial film were 2.44 ± 0.19 MPa, 6.40 ± 1.13%, 3.19 ± 0.90%, and 3.18 ± 0.63 gmm/kPa hm(2), respectively. The antimicrobial DMM films have demonstrated a potential to be applied to foods as wraps or coatings to control the growth of L. monocytogenes. Copyright © 2011 Elsevier B.V. All rights reserved.

  14. Predicting Film Genres with Implicit Ideals

    OpenAIRE

    Olney, Andrew McGregor

    2013-01-01

    We present a new approach to defining film genre based on implicit ideals. When viewers rate the likability of a film, they indirectly express their ideal of what a film should be. Across six studies we investigate the category structure that emerges from likability ratings and the category structure that emerges from the features of film. We further compare these data-driven category structures with human annotated film genres. We conclude that film genres are structured more around ideals t...

  15. Electrical initiation of an energetic nanolaminate film

    Science.gov (United States)

    Tringe, Joseph W.; Gash, Alexander E.; Barbee, Jr., Troy W.

    2010-03-30

    A heating apparatus comprising an energetic nanolaminate film that produces heat when initiated, a power source that provides an electric current, and a control that initiates the energetic nanolaminate film by directing the electric current to the energetic nanolaminate film and joule heating the energetic nanolaminate film to an initiation temperature. Also a method of heating comprising providing an energetic nanolaminate film that produces heat when initiated, and initiating the energetic nanolaminate film by directing an electric current to the energetic nanolaminate film and joule heating the energetic nanolaminate film to an initiation temperature.

  16. Predicting film genres with implicit ideals

    Directory of Open Access Journals (Sweden)

    Andrew McGregor Olney

    2013-01-01

    Full Text Available We present a new approach to defining film genre based on implicit ideals. When viewers rate the likability of a film, they indirectly express their ideal of what a film should be. Across six studies we investigate the category structure that emerges from likability ratings and the category structure that emerges from the features of film. We further compare these data-driven category structures with human annotated film genres. We conclude that film genres are structured more around ideals than around features of film. This finding lends experimental support to the notion that film genres are set of shifting, fuzzy, and highly contextualized psychological categories.

  17. Predicting film genres with implicit ideals.

    Science.gov (United States)

    Olney, Andrew McGregor

    2012-01-01

    We present a new approach to defining film genre based on implicit ideals. When viewers rate the likability of a film, they indirectly express their ideal of what a film should be. Across six studies we investigate the category structure that emerges from likability ratings and the category structure that emerges from the features of film. We further compare these data-driven category structures with human annotated film genres. We conclude that film genres are structured more around ideals than around features of film. This finding lends experimental support to the notion that film genres are set of shifting, fuzzy, and highly contextualized psychological categories.

  18. Predicting Film Genres with Implicit Ideals

    Science.gov (United States)

    Olney, Andrew McGregor

    2013-01-01

    We present a new approach to defining film genre based on implicit ideals. When viewers rate the likability of a film, they indirectly express their ideal of what a film should be. Across six studies we investigate the category structure that emerges from likability ratings and the category structure that emerges from the features of film. We further compare these data-driven category structures with human annotated film genres. We conclude that film genres are structured more around ideals than around features of film. This finding lends experimental support to the notion that film genres are set of shifting, fuzzy, and highly contextualized psychological categories. PMID:23423823

  19. Organized organic ultrathin films fundamentals and applications

    CERN Document Server

    Ariga, Katsuhiko

    2012-01-01

    This handy reference is the first comprehensive book covering both fundamentals and recent developments in the field with an emphasis on nanotechnology. Written by a highly regarded author in the field, the book details state-of-the-art preparation, characterization and applications of thin films of organic molecules and biomaterials fabricated by wet processes and also highlights applications in nanotechnology The categories of films covered include monomolecular films (monolayers) both on a water surface and on a solid plate, Langmuir-Blodgett films (transferred multilayer films on a solid plate from a water surface), layer-by-layer films (adsorbed multilayer films on a solid support), and spontaneously assembled films in solution.

  20. Võitis õige film / Kaja Lotman

    Index Scriptorium Estoniae

    Lotman, Kaja, 1960-

    2006-01-01

    Lihulas toimunud loodusfilmide festivalil tunnistati peapreemia vääriliseks režissööride Mark Deeble'i ja Victoria Stone'i Keenias filmitud film "Puude kuninganna" ( Suurbritannia, Keenia, Jaapani, USA, Saksamaa koostööfilm)