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Sample records for thiobacillus ferrooxidans isolated

  1. THE DEPRESSION OF PYRITE FLOTATION BY THIOBACILLUS FERROOXIDANS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The experimental studies on the microbial flotation of a pure pyrite sample using Thiobacillus ferrooxidans was conducted in the laboratory. The results indicate that Thiobacillus ferrooaidans has strong depression effect on the flotation of pyrite. Thiobacillus f errooxidans can adsorb on the surface of pyrite in a very short time (a few min. ), changing the surface from hydrophobic into hydrophilic and making the pyrite particles to lose their floatability. Therefore, Thiobacillus ferrooxidans is an effective microbial depressant of pyrite. It has also been pointed out that the depression of pyrite by Thiobacillus ferrooxidans is caused by the adsorption of the microbial colloids, but not by the oxidation effect.

  2. Growth of Thiobacillus ferrooxidans on elemental sulfur

    International Nuclear Information System (INIS)

    Espejo, R.T.; Romero, P.

    1987-01-01

    Growth kinetics of Thiobacillus ferrooxidans in batch cultures, containing prills of elementary sulfur as the sole energy source, were studied by measuring the incorporation of radioactive phosphorus in free and adsorbed bacteria. The data obtained indicate an initial exponential growth of the attached bacteria until saturation of the susceptible surface was reached, followed by a linear release of free bacteria due to successive replication of a constant number of adsorbed bacteria. These adsorbed bacteria could continue replication provided the colonized prills were transferred to fresh medium each time the stationary phase was reached. The bacteria released from the prills were unable to multiply, and in the medium employed they lost viability with a half-live of 3.5 days. The spreading of the progeny on the surface was followed by staining the bacteria on the prills with crystal violet; this spreading was not uniform but seemed to proceed through distortions present in the surface. The specific growth rate of T. ferrooxidans ATCC 19859 was about 0.5 day -1 , both before and after saturation of the sulfur surface. The growth of adsorbed and free bacteria in medium containing both ferrous iron and elementary sulfur indicated that T. ferrooxidans can simultaneously utilize both energy sources

  3. Work within the coordinated programme on bacterial leaching of uranium ores. Immunological identification of Thiobacillus ferrooxidans and Thiobacillus thiooxidans

    International Nuclear Information System (INIS)

    Rhee, K.S.

    1978-04-01

    Little is known of the antigenic structure of Thiobacillus. In the composition of the antigens of gram negative bacteria the polysaccharide moiety endows some specificity permitting immunological identification. The report considers work on attempts to isolate the type specific component from T. thiooxidans and T ferrooxidans. The fractionation procedures presented suggest that the presence of one or a few such type specific major protein antigen fractions from both of the T. ferrooxidans and the T. thiooxidans seems to be originated from the cytoplasm of the bacteria, since it is believed that the glycoprotein fractions which was derived from the cell wall are the common antigenic fraction between the T. ferrooxidans and the T. thiooxidans, respectively. In this regard, it is of great interest that the T. ferrooxidans or the T. thiooxidans appears not to have the type-specific antigens on their LPS or polysaccharide moiety in contrast to the other gram-negative bacteria. Thus, it is strongly believed that the envelopes of these bacteria contain both glycoproteins bearing common antigenicity, since the T. ferrooxidans and the T. thiooxidans have a structually different type-specific antigen moiety according to the results polyacrylamide gel electrophoresis

  4. A novel mineral flotation process using Thiobacillus ferrooxidans.

    Science.gov (United States)

    Nagaoka, T; Ohmura, N; Saiki, H

    1999-08-01

    Oxidative leaching of metals by Thiobacillus ferrooxidans has proven useful in mineral processing. Here, we report on a new use for T. ferrooxidans, in which bacterial adhesion is used to remove pyrite from mixtures of sulfide minerals during flotation. Under control conditions, the floatabilities of five sulfide minerals tested (pyrite, chalcocite, molybdenite, millerite, and galena) ranged from 90 to 99%. Upon addition of T. ferrooxidans, the floatability of pyrite was significantly suppressed to less than 20%. In contrast, addition of the bacterium had little effect on the floatabilities of the other minerals, even when they were present in relatively large quantities: their floatabilities remained in the range of 81 to 98%. T. ferrooxidans thus appears to selectively suppress pyrite floatability. As a consequence, 77 to 95% of pyrite was removed from mineral mixtures while 72 to 100% of nonpyrite sulfide minerals was recovered. The suppression of pyrite floatability was caused by bacterial adhesion to pyrite surfaces. When normalized to the mineral surface area, the number of cells adhering to pyrite was significantly larger than the number adhering to other minerals. These results suggest that flotation with T. ferrooxidans may provide a novel approach to mineral processing in which the biological functions involved in cell adhesion play a key role in the separation of minerals.

  5. Specific dot-immunobinding assay for detection and enumeration of Thiobacillus ferrooxidans

    International Nuclear Information System (INIS)

    Arredondo, R.; Jerez, C.A.

    1989-01-01

    A specific and very sensitive dot-immunobinding assay for the detection and enumeration of the bioleaching microorganism Thiobacillus ferrooxidans was developed. Nitrocellulose spotted with samples was incubated with polyclonal antisera against whole T. ferrooxidans cells and then in 125 I-labeled protein A or 125 I-labeled goat antirabbit immunoglobulin G; incubation was followed by autoradiography. Since a minimum of 10 3 cells per dot could be detected, the method offers the possibility of simultaneous processing of numerous samples in a short time to monitor the levels of T. ferrooxidans in bioleaching operations

  6. Ferrous Iron Oxidation by Thiobacillus ferrooxidans: Inhibition with Benzoic Acid, Sorbic Acid, and Sodium Lauryl Sulfate

    OpenAIRE

    Onysko, Steven J.; Kleinmann, Robert L. P.; Erickson, Patricia M.

    1984-01-01

    Benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds.

  7. Ferrous Iron Oxidation by Thiobacillus ferrooxidans: Inhibition with Benzoic Acid, Sorbic Acid, and Sodium Lauryl Sulfate

    Science.gov (United States)

    Onysko, Steven J.; Kleinmann, Robert L. P.; Erickson, Patricia M.

    1984-01-01

    Benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited bacterial oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds. PMID:16346592

  8. Production of ferric sulphate from pyrite by thiobacillus ferrooxidans. Application to uranium ore leaching

    International Nuclear Information System (INIS)

    Rouas, C.

    1988-12-01

    A process for uranium extraction by oxidizing solutions of ferric sulphate produced by T. ferrooxidans from pyrite is developed. A new counting method specific of T. ferrooxidans is designed. An uranium resistant wild strain, with oxidizing properties as high as the strain ATCC 19859, is isolated. Optimal conditions for ferric sulphate production from pyrite are defined (pH 1.8, density of the medium 1.2%, pyrite granulometry [fr

  9. Mathematical model of the oxidation of ferrous iron by a biofilm of Thiobacillus ferrooxidans.

    Science.gov (United States)

    Mesa, M M; Macías, M; Cantero, D

    2002-01-01

    Microbial oxidation of ferrous iron may be a viable alternative method of producing ferric sulfate, which is a reagent used for removal of H(2)S from biogas. The paper introduces a kinetic study of the biological oxidation of ferrous iron by Thiobacillus ferrooxidans immobilized on biomass support particles (BSP) composed of polyurethane foam. On the basis of the data obtained, a mathematical model for the bioreactor was subsequently developed. In the model described here, the microorganisms adhere by reversible physical adsorption to the ferric precipitates that are formed on the BSP. The model can also be considered as an expression for the erosion of microorganisms immobilized due to the agitation of the medium by aeration.

  10. Short communication: Adverse effect of surface-active reagents on the bioleaching of pyrite and chalcopyrite by Thiobacillus ferrooxidans.

    Science.gov (United States)

    Huerta, G; Escobar, B; Rubio, J; Badilla-Ohlbaum, R

    1995-09-01

    Oxidation of Fe(II) iron and bioleaching of pyrite and chalcopyrite by Thiobacillus ferrooxidans was adversely affected by isopropylxanthate, a flotation agent, and by LIX 984, a solvent-extraction agent, each at ≤ 1 g/l. The reagents/l were adsorbed on the bacterial surface, decreasing the bacteria's development and preventing biooxidation. Both reagents inhibited the bioleaching of pyrite and LIX 984 also inhibited the bioleaching of chalcopyrite.

  11. Constitutive synthesis of a transport function encoded by the Thiobacillus ferrooxidans merC gene cloned in Escherichia coli

    International Nuclear Information System (INIS)

    Kusano, Tomonobu; Ji, Guangyong; Silver, S.; Inoue, Chihiro

    1990-01-01

    Mercuric reductase activity determined by the Thiobacillus ferrooxidans merA gene (cloned and expressed constitutively in Escherichia coli) was measured by volatilization of 203 Hg 2+ . (The absence of a merR regulatory gene in the cloned Thiobacillus mer determinant provides a basis for the constitutive synthesis of this system.) In the absence of the Thiobacillus merC transport gene, the mercury volatilization activity was cryptic and was not seen with whole cells but only with sonication-disrupted cells. The Thiobacillus merC transport function was compared with transport via the merT-merP system of plasmid pDU1358. Both systems, cloned and expressed in E. coli, governed enhanced uptake of 203 Hg 2+ in a temperature- and concentration-dependent fashion. Uptake via MerT-MerP was greater and conferred greater hypersensitivity to Hg 2+ than did uptake with MerC. Mercury uptake was inhibited by N-ethylmaleimide but not by EDTA. Ag + salts inhibited mercury uptake by the MerT-MerP system but did not inhibit uptake via MerC. Radioactive mercury accumulated by the MerT-MerP and by the MerC systems was exchangeable with nonradioactive Hg 2+

  12. Distribution, ecology and inhibition of Thiobacillus ferrooxidans in relation to acid drainage from Witwatersrand gold mine dumps

    International Nuclear Information System (INIS)

    Whillier, P.A.

    1987-03-01

    The distribution and ecology of Thiobacillus ferrooxidans in gold mine dumps and possible means for its inhibition were investigated. A literature survey of the micro-ecology of mine waste dumps in various parts of the world was undertaken. A linear alkylbenzene sulphonate (LAS), NANSA 80/S, and a cetyl pyridinium chloride, Ceepryn, were tested as possible inhibitors for mine dump application. The LAS was rejected because it is poorly soluble in water and required higher concentrations than SLS for the inhibition of T.ferrooxidans. Ceepryn was an efficient inhibitor, but its efficiency was dramatically impeded in the presence of mine dump sand making it unsuitable for application on dumps. The SLS and LAS were tested against a mixed population of T.ferrooxidans from gold mine dumps and these bacteria were shown to be marginally more resistant to the inhibitors than the pure T.ferrooxidans culture. Sampling from mine dumps on the Witwatersrand suggested that the major T.ferrooxidans populations occurred in the moist sand of the drainage areas at the base of dumps, with few viable iron-oxidising bacteria located on the surfaces or in the centre of dumps. Sites of low moisture in dumps contained few or no viable bacteria. In the laboratory the bacterial viability decreased rapidly with loss of moisture from the sand. Moisture was shown to be important to bacterial activity and should be considered with respect to acid drainage control. Experimental sand columns showed that iron was leached with water from mine dump sand in the absence and presence of bacteria. In this study substrates, moisture, oxygen and carbon dioxide availability, ph, temperature, microorganisms and metal pollutants of uranium waste dumps are also covered

  13. Structure/function relationship of the rusticyanin among thiobacillus ferroxidans: from the fermenter to the crystal; Relations structure/fonction de la rusticyanine chez thiobacillus ferrooxidans: du fermenteur au cristal

    Energy Technology Data Exchange (ETDEWEB)

    Nunzi, F.

    1996-09-23

    The commercial extraction of copper and uranium from ores by microbial leaching turns to account the iron oxidation capacity of Thiobacillus ferroxidans. The iron oxidation involves an electron transport chain localized in the peri-plasmic space of the cell. The aim of our work is to study the structure-function relationships of rusticyanin, the most important component of this respiratory chain. Rusticyanin is a blue copper protein and has been characterized from a new strain of Thilbacillus ferrooxidans. A preliminary electrochemical study has been made with a new modified-gold electrode and we have examined, in particular, the pH dependence of the high redox potential of rusticyanin. Its amino acid sequence has been determined and a comparison with two other rusticyanin sequences, isolated from different strains, shows a high degree of homology. A structural alignment with six other blue copper proteins allows to propose four residues as copper ligands, His 84, Cys 138, His 143 and Met 148. The supposed factors responsible for the high redox potential of rusticyanin are discussed. (author)

  14. Charge and softness of the outer part of the cell wall of Thiobacillus ferrooxidans in the low ionic strength medium

    Directory of Open Access Journals (Sweden)

    Škvarla Jiří

    2002-03-01

    Full Text Available The surface charge and surface potential are parameters influencing the microbial adhesion phenomenon through the electrostatic interaction between bacteria and substrates. The Smoluchowski equation, originally developed for estimating the above parameters from the experimentally accessible electrophoretic mobility of rigid colloid particles, is however inapplicable to the elastic bacterial cells. The problem is that the outer cell wall of bacteria is a layer with a complex polyelectrolyte structure. In this article, the OhshimaLs model of the gsofth particle is applied to describe the surface electrostatics of Thiobacillus ferrooxidans cells by measuring their electrophoretic mobility in distilled water as a function of a (low ionic strength and pH. In this model, the rigid core is considered to be covered with a charged ion-penetrable layer of polyelectrolytes. Two model parameters have been determined by the curve fitting at pH from 3.2 to 5.8, namely the number density of the dissociated groups N and the softness parameter 1/ƒÉ of the polyelectrolyte layer of the bacterium. A disagreement of the best fit parameters (evaluated by the correlation coefficient with the analogous parameters determined for other colloids (including bacterial cells in aqueous solutions of a high ionic strength is discussed.

  15. A kinetic study of the depyritization of oil shale HCl-kerogen concentrate by Thiobacillus ferrooxidans at different temperatures

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    OLGA CVETKOVIC

    2003-05-01

    Full Text Available The results of kinetic studies of bacterial depyritization of HCl-kerogen concentrate of Aleksinac (Serbia oil shale by the chemolithoautotrophic thionic bacteria Thiobacillus ferrooxidans under discontinuous laboratory conditions at various temperatures (0, 20, 28 and 37°C at a pH of ca. 1.5 are presented in this paper. Low pH prevents the occurrence of the precipitation of iron(III-ion hydrolysis products on the substrate particles and thereby reduces the process efficiency. Bacterial depyritization is developed as per kinetics of the first order. The activation energy which points to a successive mechanism of pyrite biooxidation, was computed from the Arrhenius plot. The biochemical kinetics indicators point to a high affinity of the bacteria toward pyrite but small values of Vmax, which are probably the result of decelerated metabolic processes due to the low pH value of the environment resp. the large difference of the pH between the external medium and the cell interior.

  16. Evidence of biogenic corrosion of titanium after exposure to a continuous culture of thiobacillus ferrooxidans grown in thiosulfate medium

    International Nuclear Information System (INIS)

    Horn, J M; Martin, S I; Masterson, B

    2000-01-01

    Experiments were undertaken to evaluate extreme conditions under which candidate materials intended for use in a proposed nuclear waste repository might be susceptible to corrosion by endogenous microorganisms. Thiobucillus ferrooxidans, a sulfur-oxidizing bacterium, was grown in continuous culture using thiosulfate as an energy source; thiosulfate is oxidized to sulfate as a metabolic endproduct by this organism. Culture conditions were optimized to produce a high-density, metabolically active culture throughout a period of long term incubation in the presence of Alloy 22 (a high nickel-based alloy) and Titanium grade 7 (Tigr7) material coupons. After seven months incubation under these conditions, material coupons were withdrawn and analyzed by high resolution microscopy and energy dispersive x-ray analyses. Alloy 22 coupons showed no detectable signs of corrosion. Tigr7, however, demonstrated distinct roughening of the coupon surface, and [presumably solubilized and precipitated] titanium was detected on Alloy 22 coupons incubated in the same T. ferrooxiduns culture vessel. Control coupons of these materials incubated in sterile thiosulfate medium did not demonstrate any signs of corrosion, thus showing that observed corrosive effects were due to the T. ferrooxidans metabolic activities. T. ferrooxidans intermediates of thiosulfate oxidation or sulfate may have caused the corrosive effects observed on Tigr7

  17. Aplicação de técnicas eletroquímicas no estudo da dissolução oxidativa da covelita (CuS por Thiobacillus ferrooxidans Electrochemical techniques applied to study the oxidative dissolution of the covellite: CuS by Thiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    Christiane Medina Teixeira

    2002-02-01

    Full Text Available Among the copper sulphides, chalcopyrite (CuFeS2, covellite (CuS and chalcocite (Cu2S are the most important source of minerals for copper mining industry. The acknowledge of behaviour of these sulphides related with bacterial leaching process are essential for optimization procedures. Despite of its importance, covellite has not deserved much interest of researchers regarding this matter. In this work it was studied the oxidation of covellite by the chemolithotrophic bacterium Thiobacillus ferrooxidans by using electrochemical techniques, such as open circuit potentials with the time and cyclic voltammetry. The experiments were carried out in acid medium (pH 1.8, containing or not Fe2+ as additional energy source, and in different periods of incubation; chemical controls were run in parallel. The results showed that a sulphur layer is formed spontaneously due the acid attack, covering the sulphide in the initial phase of incubation, blocking the sulphide oxidation. However, the bacterium was capable to oxidize this sulphur layer. In the presence of Fe2+ as supplemental energy source, the corrosion process was facilitated, because ocurred an indirect oxidation of covellite by Fe3+, which was produced by T. ferrooxidans oxidation of the Fe2+ added in the medium.

  18. The role of sulfur-oxidizing bacteria Thiobacillus thiooxidans in pyrite weathering

    International Nuclear Information System (INIS)

    Sasaki, K.; Tsunekawa, M.; Ohtsuka, T.; Konno, H.

    1998-01-01

    The paper investigates the role of the sulfur-oxidizing bacteria Thiobacillus thiooxidans in pyrite weathering in order to clarify the effects of the bacteria on the dissolution behavior of pyrite and the formation of secondary minerals using Raman spectroscopy and powder X-ray diffraction (XRD) in addition to solution analysis. It was found that T. thiooxidans, when present with the iron-oxidizing bacteria Thiobacillus ferrooxidans, enhanced the dissolution of Fe and S species for pyrite, whereas T. thiooxidans alone did not oxidize pyrite. Enhancement of the consumption of elemental sulfur and regeneration of Fe(II) ions were also observed with T. thiooxidans together with T. ferrooxidans, while this did not occur with T. ferrooxidans alone

  19. A Comparative Study on the Effect of Flotation Reagents on Growth and Iron Oxidation Activities of Leptospirillum ferrooxidans and Acidithiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    Mohammad Jafari

    2016-12-01

    Full Text Available Recently, extraction of metals from different resources using a simple, efficient, and low-cost technique-known as bioleaching-has been widely considered, and has turned out to be an important global technology. Leptospirillum ferrooxidans and Acidithiobacillus (Thiobacillus ferrooxidans are ubiquitous bacteria in the biomining industry. To date, the effects of commercial flotation reagents on the biooxidation activities of these bacteria have not been thoroughly studied. This investigation, by using various systematic measurement methods, studied the effects of various collectors and frothers (collectors: potassium amylxanthate, potassium isobutyl-xanthate, sodium ethylxanthate, potassium isopropylxanthate, and dithiophosphate; and frothers: pine oil and methyl isobutyl carbinol on L. ferrooxidans and A. ferrooxidans activities. In general, results indicate that in the presence of these collectors and frothers, L. ferrooxidans is less sensitive than T. ferrooxidans. In addition, the inhibition effect of collectors on both bacteria is recommended in the following order: for the collectors, potassium isobutyl-xanthate > dithiophosphate > sodium ethylxanthate > potassium isobutyl-xanthate > potassium amylxanthate; and for the frothers, methyl isobutyl carbinol > pine oil. These results can be used for the optimization of biometallurgical processes or in the early stage of a process design for selection of flotation reagents.

  20. Reduction of chromium (VI by the indirect action of Thiobacillus thioparus

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    E. Donati

    2003-03-01

    Full Text Available The microbial reduction of chromium(VI to chromium(III has been one of the most widely studied forms of metal bioremediation. Recently, we have found that Thiobacillus ferrooxidans and Thiobacillus thiooxidans, growing on elemental sulphur, can indirectly promote chromium(VI reduction by producing reducing agents such as sulphite and thiosulphate, which abiotically reduce chromium(VI. Those species of Thiobacillus are acidophilic bacteria which grow optimally at pH values lower than 4. However, most of those reducing agents are stabilised at higher pH values. Thus, the present paper reports on the ability to reduce chromium(VI using another specie of Thiobacilli, Thiobacillus thioparus, which is able to grow at pH close to 7.0. T. thioparus cultures were carried out in a fermentation vessel containing medium and sulphur as the sole energy source and maintained at 30ºC and 400 rpm. The pH was adjusted to 6.0, 7.0 or 8.0 and maintained with the automatic addition of KOH. Our results show high chromium (VI reduction values (close to 100% at the end of bacterial growth at the three pH values. The results of these experiments are very promising for development of a microbiological process to be used in the detoxification of chromium(VI-polluted effluents.

  1. Factors Influencing Degradation of Mercaptans by Thiobacillus ...

    African Journals Online (AJOL)

    Degradation of methylmercaptans by Thiobacillus thioparus TK-m was influenced by pH of the reaction medium. Ratios of headspace concentrations in empty vials and those of acidified buffer solutions were less than 1.0. 95% of the H2S was in headspace with the remaining 5% in solution upon acidification. The values for ...

  2. Biocompatibility evaluation of magnetosomes formed by Acidithiobacillus ferrooxidans

    International Nuclear Information System (INIS)

    Yan Lei; Yue Xiaoxuan; Zhang Shuang; Chen Peng; Xu Zhiliang; Li Yang; Li Hongyu

    2012-01-01

    Magnetite nanocrystal has been extensively used in biomedical field. Currently, an interesting alternative to synthetic magnetic Fe 3 O 4 nanoparticles, called magnetosome, has been found in magnetotactic bacteria. It has been reported that Acidithiobacillus ferrooxidans (At. ferrooxidans) has a potential to synthesize magnetosome. In this study, transmission electron microscope (TEM) was used to analyze the magnetite particles in At. ferrooxidans BY-3. The magnetosomes formed by this bacterium were isolated by a method combining ultracentrifugation and magnetic separation. Crystalline phase and surface functional group of the magnetosomes were investigated by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), respectively. Biocompatibility of the magnetosomes was systematically evaluated at various concentrations (0.5, 1.0, 2.0 and 4.0 mg/ml). MTT test, hemolysis assay and Micronucleus Test were carried out to evaluate in vitro cytotoxicity, blood toxicity and genotoxicity of magnetosomes, respectively. Under these conditions, magnetosomes showed no cytotoxic, genotoxic and hemolytic effects up to 4.0 mg/ml indicating good biocompatibility of these biological nanoparticles. These revealed that the magnetosomes might have a potential for biotechnological and biomedical applications in the future. - Highlights: ► The production of magnetosomes from At. ferrooxidans has been easily available. ► Several techniques are used to characterize properties of the magnetosomes. ► The magnetosomes have no cytotoxicity, no hemolysis activity and no genotoxicity.

  3. Study of a bacterial leaching program for uranium ores by Thiobacillus ferroxidans

    International Nuclear Information System (INIS)

    Garcia Junior, O.

    1989-01-01

    The development of a bacterial leaching program for uranium ores is studied. Three basic points are presented: isolation and purification of Thiobacillus ferroxidans, as well Thiobacillus thio oxidans; physiological studies of growth and respiratory metabolism of T. ferroxidans; uranium leaching from two types of ore by T. ferroxidans action, on laboratory, semi pilot and pilot scales. The bacterial leaching studies were carried out in shake flasks, percolation columns (laboratory and semi pilot) and in heap leaching (pilot). The potential of the ores studied in relation to bacterial action, was first showed in shake flask experiments. The production of H 2 S O 4 and Fe 3+ was a result of the bacterial activity on both ore samples containing pyrite (Fe S 2 ). These two bacterial products resulted in a high uranium and molybdenum extraction and a lower sulfuric acid consumption compared to the sterilized treatments. Similar results were obtained in percolation column at the same scale (lab). (author)

  4. Evaluating Acidithiobacillus ferrooxidans bacterial oxidation of sulphur compounds using FTIR and X-ray diffraction assays

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    Alexandra Muñoz

    2003-01-01

    Full Text Available A native bacterial strain capable of oxidising ferrous iron and sulphur compounds was isolated from effluent and material from the La Maruja gold mine in the municipality of Marmato (Caldas; this was biochemically identified as being Acidithiobacillus ferrooxidans. This strain's ability to oxidise metallic sulphide concentrates having two differ-ent pulp proportions and two particle sizes was evaluated. Sulphide bio-oxidation was observed after 15 days showing this strain's catalytic action on the mineral break-down process. Key words: bio-oxidation; bio-leaching; A. ferrooxidans; sulphides

  5. Arsenic tolerance and bioleaching from realgar based on response surface methodology by Acidithiobacillus ferrooxidans isolated from Wudalianchi volcanic lake, northeast China

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    Lei Yan

    2017-01-01

    Conclusion: From this work we were successful in isolating an acidophilic, arsenic tolerant ferrous iron-oxidizing bacterium. The BBD-RSM analysis showed that maximum arsenic bioleaching rate obtained under optimum conditions, and the most effective factor for arsenic leaching was initial ferrous ion concentration. These revealed that BYQ-12 could be used for bioleaching of arsenic from arsenical minerals.

  6. Draft genome sequence of Acidithiobacillus ferrooxidans YQH-1

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    Lei Yan

    2015-12-01

    Full Text Available Acidithiobacillus ferrooxidans YQH-1 is a moderate acidophilic bacterium isolated from a river in a volcano of Northeast China. Here, we describe the draft genome of strain YQH-1, which was assembled into 123 contigs containing 3,111,222 bp with a G + C content of 58.63%. A large number of genes related to carbon dioxide fixation, dinitrogen fixation, pH tolerance, heavy metal detoxification, and oxidative stress defense were detected. The genome sequence can be accessed at DDBJ/EMBL/GenBank under the accession no. LJBT00000000.

  7. Visualization of capsular polysaccharide induction in Acidithiobacillus ferrooxidans

    NARCIS (Netherlands)

    Bellenberg, S.; Leon Morales, C.F.; Sand, W.; Vera, M.

    2012-01-01

    Extracellular Polymeric Substances (EPS) are of fundamental importance for attachment to metal sulfides, biofilm formation and leaching efficiency of Acidithiobacillus ferrooxidans. In this work we have visualized the capsular polysaccharides (CPS) of A. ferrooxidans ATCC 23270 using the

  8. Application of Acidithiobacillus Ferrooxidans in coal flotation

    Energy Technology Data Exchange (ETDEWEB)

    Amini, E.; Hosseini, T.R.; Oliazadeh, M.; Kolahdoozan, M. [University of Queensland, Brisbane, Qld. (Australia)

    2009-07-01

    Bioflotation is a potential method for removing pyritic sulphur from coal. Sodium cyanide is a well-known depressant for pyrite in flotation of sulphide minerals; however, for coal this reagent is unacceptable from the environmental point of view. This study investigates an alternate to sodium cyanide, Acidithiobacillus Ferrooxidans, a nonharmful bacterial reagent as a pyrite depressant. The flotation behavior of pyrite and other gangue particles using the sodium cyanide and the Ferrooxidans is compared by applying the general first-order flotation model. The kinetic parameters extracted from the model demonstrated that the modified flotation rate of pyrite was reduced, and the selectivity between coal and gangue was improved using the bacteria. These results indicate that Acidithiobacillus Ferrooxidans has potential in removing pyritic sulfur from coal.

  9. ribB and ribBA genes from Acidithiobacillus ferrooxidans: expression levels under different growth conditions and phylogenetic analysis.

    Science.gov (United States)

    Knegt, Fábio H P; Mello, Luciane V; Reis, Fernanda C; Santos, Marcos T; Vicentini, Renato; Ferraz, Lúcio F C; Ottoboni, Laura M M

    2008-01-01

    Acidithiobacillus ferrooxidans is a Gram-negative, chemolithoautotrophic bacterium involved in metal bioleaching. Using the RNA arbitrarily primed polymerase chain reaction (RAP-PCR), we have identified several cDNAs that were differentially expressed when A. ferrooxidans LR was submitted to potassium- and phosphate-limiting conditions. One of these cDNAs showed similarity with ribB. An analysis of the A. ferrooxidans ATCC 23270 genome, made available by The Institute for Genomic Research, showed that the ribB gene was not located in the rib operon, but a ribBA gene was present in this operon instead. The ribBA gene was isolated from A. ferrooxidans LR and expression of both ribB and ribBA was investigated. Transcript levels of both genes were enhanced in cells grown in the absence of K2HPO4, in the presence of zinc and copper sulfate and in different pHs. Transcript levels decreased upon exposure to a temperature higher than the ideal 30 degrees C and at pH 1.2. A comparative genomic analysis using the A. ferrooxidans ATCC 23270 genome revealed similar putative regulatory elements for both genes. Moreover, an RFN element was identified upstream from the ribB gene. Phylogenetic analysis of the distribution of RibB and RibBA in bacteria showed six different combinations. We suggest that the presence of duplicated riboflavin synthesis genes in bacteria must provide their host with some benefit in certain stressful situations.

  10. The environmental context of Acidithiobacillus ferrooxidans and its potential role as an ecosystem engineer in sulphidic mine waste

    Energy Technology Data Exchange (ETDEWEB)

    Ebenaa, Gustav

    2001-06-01

    Microorganisms are the causative agent of the environmental problems since they catalyse the weathering of the (sulphidic) waste. The chemical oxidation alone is not fast enough to create any severe environmental problems. Acidithiobacillus ferrooxidans is thought to be a key organism in weathering of sulphide minerals. A. ferrooxidans is affected by several more or less abiotic factors. The influence of temperature, pH and nutrient deficiency as potentially limiting factors for the activity of A. ferrooxidans has been investigated. It seems that temperature has less influence on its activity, but rather reflects the origin of the bacterial isolate. An alkaline pH seems enough to hinder growth and activity. The nutrients do not seem to be a limiting factor in the studied environment. The possible regulation of the activity of A. ferrooxidans is therefore a way to, at least partly, mitigate the environmental impact from mine waste. Waste from the mining industry is the largest waste problem in Sweden. With amounts over 600 million tonnes one could easily imagine the tremendous cost involved in the abatement. The MiMi-programme, with researchers from several relevant fields, has as its aim to evaluate present and to find alternative techniques to mitigate the environmental impact from mine waste. The understanding of A. ferrooxidans and its role as an ecosystem engineer is essential both in evaluating present techniques and even more so in finding alternative abatement techniques for sulphidic mine waste.

  11. [Application of immunologic methods to the analysis of bio-leaching bacteria].

    Science.gov (United States)

    Coto, O; Fernández, A I; León, T; Rodríguez, D

    1994-09-01

    Pure cultures of Thiobacillus ferrooxidans and mixed cultures of Thiobacillus ferrooxidans and Leptospirillum ferrooxidans isolated from the Matahambre mine (Cuba) were used to fit immunodiffusion and immunoelectron microscopy to the study of iron oxidizing bacteria. The possibilities, advantages and limits of those techniques have been studied from both the identification and the serological characterization points of view. Finally, the efficiency of these methods was tested by applying them to the identification of microorganisms from acidic waters from the mine.

  12. Occurrence of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in uranium mine-Caldas uranium mining and extraction plant, Brazil (CUMEP)

    International Nuclear Information System (INIS)

    Gomes, H.A.; Garcia, O.; Gomes, J.E.; Rabello, E.; Cannavan, F.S.; Tsai, S.M.

    2005-01-01

    percentages of incidence and highest values of A. ferrooxidans and A. thiooxidans counting observed in the sites 0.75, BIA, PM, WR4, WR8 and BE, we can consider these sites as the main locations of acid drainage occurrence and bioleaching bacteria action in the CUMEP. Thus, highest priority should be taking into account for decommission measures, once these critical sites are considered as hot spot. The main isolates from these areas are being identified by conventional microbiological methods and by cloning and sequencing their 16S rRNA genes.

  13. Zinc bioleaching from an iron concentrate using Acidithiobacillus ferrooxidans strain from Hercules Mine of Coahuila, Mexico

    Science.gov (United States)

    Núñez-Ramírez, Diola Marina; Solís-Soto, Aquiles; López-Miranda, Javier; Pereyra-Alférez, Benito; Rutiaga-Quiñónes, Miriam; Medina-Torres, Luis; Medrano-Roldán, Hiram

    2011-10-01

    The iron concentrate from Hercules Mine of Coahuila, Mexico, which mainly contained pyrite and pyrrhotite, was treated by the bioleaching process using native strain Acidithiobacillus ferrooxidans ( A. ferrooxidans) to determine the ability of these bacteria on the leaching of zinc. The native bacteria were isolated from the iron concentrate of the mine. The bioleaching experiments were carried out in shake flasks to analyze the effects of pH values, pulp density, and the ferrous sulfate concentration on the bioleaching process. The results obtained by microbial kinetic analyses for the evaluation of some aspects of zinc leaching show that the native bacteria A. ferrooxidans, which is enriched with a 9K Silverman medium under the optimum conditions of pH 2.0, 20 g/L pulp density, and 40 g/L FeSO4, increases the zinc extraction considerably observed by monitoring during15 d, i.e., the zinc concentration has a decrease of about 95% in the iron concentrate.

  14. [Effect of simulated heavy metal leaching solution of electroplating sludge on the bioactivity of Acidithiobacillus ferrooxidans].

    Science.gov (United States)

    Xie, Xin-Yuan; Sun, Pei-De; Lou, Ju-Qing; Guo, Mao-Xin; Ma, Wang-Gang

    2013-01-01

    An Acidithiobacillus ferrooxidans strain WZ-1 was isolated from the tannery sludge in Wenzhou, Zhejiang Province in China. The cell of WZ-1 strain is Gram negative and rod-shaped, its 16S rDNA sequence is closely related to that of Acidithiobacillus ferrooxidans ATCC23270 with 99% similarity. These results reveal that WZ-1 is a strain of Acidithiobacillus ferrooxidans. The effects of Ni2+, Cr3+, Cu2+, Zn2+ and 5 kinds of simulated leaching solutions of electroplating sludge on the bioactivity of Fe2+ oxidation and apparent respiratory rate of WZ-1 were investigated. The results showed that Ni2+ and Cr3+ did not have any influence on the bioactivity of WZ-1 at concentrations of 5.0 g x L(-1) and 0.1 g x L(-1), respectively. WZ-1 showed tolerance to high levels of Ni2+, Zn2+ (about 30.0 g x L(-1)), but it had lower tolerance to Cr3+ and Cu2+ (0.1 g x L(-1) Cr3+ and 2.5 g x L(-1) Cu2+). Different kinds of simulated leaching solution of electroplating sludge had significant differences in terms of their effects on the bioactivity of WZ-1 with a sequence of Cu/Ni/Cr/Zn > Cu/Ni/Zn > Cu/Cr/Zn > Cu/Ni/Cr > Ni/Cr/Zn.

  15. Impact of solvent extraction organics on bioleaching by Acidithiobacillus ferrooxidans

    Science.gov (United States)

    Yu, Hualong; Liu, Xiaorong; Shen, Junhui; Chi, Daojie

    2017-03-01

    Solvent extraction organics (SX organics) entrained and dissoluted in the raffinate during copper SX operation, can impact bioleaching in case of raffinate recycling. The influence of SX organics on bioleaching process by Acidithiobacillus ferrooxidans (At. ferrooxidans) has been investigated. The results showed that, cells of At. ferrooxidans grew slower with contaminated low-grade chalcopyrite ores in shaken flasks bioleaching, the copper bioleaching efficiency reached 15%, lower than that of 24% for uncontaminated minerals. Obviously, the SX organics could adsorb on mineral surface and hinder its contact with bacterials, finanlly lead to the low bioleaching efficiency.

  16. Genetic manipulation of the obligate chemolithoautotrophic bacterium Thiobacillus denitrificans

    Energy Technology Data Exchange (ETDEWEB)

    Beller, H.R.; Legler, T.C.; Kane, S.R.

    2011-07-15

    Chemolithoautotrophic bacteria can be of industrial and environmental importance, but they present a challenge for systems biology studies, as their central metabolism deviates from that of model organisms and there is a much less extensive experimental basis for their gene annotation than for typical organoheterotrophs. For microbes with sequenced genomes but unconventional metabolism, the ability to create knockout mutations can be a powerful tool for functional genomics and thereby render an organism more amenable to systems biology approaches. In this chapter, we describe a genetic system for Thiobacillus denitrificans, with which insertion mutations can be introduced by homologous recombination and complemented in trans. Insertion mutations are generated by in vitro transposition, the mutated genes are amplified by the PCR, and the amplicons are introduced into T. denitrificans by electroporation. Use of a complementation vector, pTL2, based on the IncP plasmid pRR10 is also addressed.

  17. Synergy between Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the Bioleaching Process of Copper

    Directory of Open Access Journals (Sweden)

    Xuecheng Zheng

    2016-01-01

    Full Text Available This study investigates the synergy of Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the bioleaching process of copper. The results showed that additional R. phaseoli could increase leaching rate and cell number of A. ferrooxidans. When the initial cell number ratio between A. ferrooxidans and R. phaseoli was 2 : 1, A. ferrooxidans attained the highest final cell number of approximately 2 × 108 cells/mL and the highest copper leaching rate of 29%, which is 7% higher than that in the group with A. ferrooxidans only. R. phaseoli may use metabolized polysaccharides from A. ferrooxidans, and organic acids could chelate or precipitate harmful heavy metals to reduce their damage on A. ferrooxidans and promote its growth. Organic acids could also damage the mineral lattice to increase the leaching effect.

  18. Synergy between Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the Bioleaching Process of Copper

    Science.gov (United States)

    Zheng, Xuecheng; Li, Dongwei

    2016-01-01

    This study investigates the synergy of Rhizobium phaseoli and Acidithiobacillus ferrooxidans in the bioleaching process of copper. The results showed that additional R. phaseoli could increase leaching rate and cell number of A. ferrooxidans. When the initial cell number ratio between A. ferrooxidans and R. phaseoli was 2 : 1, A. ferrooxidans attained the highest final cell number of approximately 2 × 108 cells/mL and the highest copper leaching rate of 29%, which is 7% higher than that in the group with A. ferrooxidans only. R. phaseoli may use metabolized polysaccharides from A. ferrooxidans, and organic acids could chelate or precipitate harmful heavy metals to reduce their damage on A. ferrooxidans and promote its growth. Organic acids could also damage the mineral lattice to increase the leaching effect. PMID:26942203

  19. Complete genome sequence of Acidimicrobium ferrooxidans type strain (ICPT)

    Energy Technology Data Exchange (ETDEWEB)

    Clum, Alicia; Nolan, Matt; Lang, Elke; Glavina Del Rio, Tijana; Tice, Hope; Copeland, Alex; Cheng, Jan-Fang; Lucas, Susan; Chen, Feng; Bruce, David; Goodwin, Lynne; Pitluck, Sam; Ivanova, Natalia; Mavrommatis, Konstantinos; Mikhailova, Natalia; Pati, Amrita; Chen, Amy; Palaniappan, Krishna; Goker, Markus; Spring, Stefan; Land, Miriam; Hauser, Loren; Chang, Yun-Juan; Jefferies, Cynthia C.; Chain, Patrick; Bristow, James; Eisen, Jonathan A.; Markowitz, Victor; Hugenholtz, Philip; Kyrpides, Nikos C.; Klenk, Hans-Peter; Lapidus, Alla

    2009-05-20

    Acidimicrobium ferrooxidans (Clark and Norris 1996) is the sole and type species of the genus, which until recently was the only genus within the actinobacterial family Acidimicrobiaceae and in the order Acidomicrobiales. Rapid oxidation of iron pyrite during autotrophic growth in the absence of an enhanced CO2 concentration is characteristic for A. ferrooxidans. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of the order Acidomicrobiales, and the 2,158,157 bp long single replicon genome with its 2038 protein coding and 54 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.

  20. Characterization of arsenic resistant and arsenopyrite oxidizing Acidithiobacillus ferrooxidans from Hutti gold leachate and effluents.

    Science.gov (United States)

    Dave, Shailesh R; Gupta, Kajal H; Tipre, Devayani R

    2008-11-01

    Four arsenic resistant ferrous oxidizers were isolated from Hutti Gold Mine Ltd. (HGML) samples. Characterization of these isolates was done using conventional microbiological, biochemical and molecular methods. The ferrous oxidation rates with these isolates were 16, 48, 34 and 34 mg L(-1)h(-1) and 15, 47, 34 and 32 mg L(-1)h(-1) in absence and presence of 20 mM of arsenite (As3+) respectively. Except isolate HGM 8, other three isolates showed 2.9-6.3% inhibition due to the presence of 20 mM arsenite. Isolate HGM 8 was able to grow in presence of 14.7 g L(-1) of arsenite, with 25.77 mg L(-1)h(-1) ferrous oxidation rate. All the four isolates were able to oxidize iron and arsenopyrite from 20 g L(-1) and 40 g L(-1) refractory gold ore and 20 g L(-1) refractory gold concentrate. Once the growth was established pH adjustment was not needed inspite of ferrous oxidation, which could be due to concurrent oxidation of pyrite. Isolate HGM 8 showed the final cell count of as high as 1.12 x 10(8) cells mL(-1) in 40 g L(-1) refractory gold ore. The isolates were grouped into one haplotypes by amplified ribosomal DNA restriction analysis (ARDRA). The phylogenetic position of HGM 8 was determined by 16S rDNA sequencing. It was identified as Acidithiobacillus ferrooxidans and strain name was given as SRHGM 1.

  1. Isolation of Sulfur Reducing and Oxidizing Bacteria Found in Contaminated Drywall

    Directory of Open Access Journals (Sweden)

    Frederick T. Guilford

    2010-02-01

    Full Text Available Drywall from China has been reported to release sulfur producing products which are corrosive to metals, result in noxious odors, and represent a significant health risk. It has been reported that these emissions produce medical symptoms such as respiratory or asthma type problems, sinusitis, gastrointestinal disorders, and vision problems in home owners and their household pets. We report here a method of identifying a causative agent for these emissions by sampling affected gypsum wallboard and subjecting those samples to Real Time Polymerase Chain Reaction [RT-PCR] studies. Specific DNA probes and primers have been designed and patented that detect a specific iron and sulfur reducing bacterium (i.e., Thiobacillus ferrooxidans. One hundred percent of affected drywall samples obtained from homes located in the southeastern United States tested positive for the presence of T. ferrooxidans. All negative controls consisting of unaffected wallboard and internal controls, Geotrichum sp., tested negative within our limits of detection.

  2. Acidithiobacillus ferrooxidans metabolism: from genome sequence to industrial applications

    Directory of Open Access Journals (Sweden)

    Blake Robert

    2008-12-01

    Full Text Available Abstract Background Acidithiobacillus ferrooxidans is a major participant in consortia of microorganisms used for the industrial recovery of copper (bioleaching or biomining. It is a chemolithoautrophic, γ-proteobacterium using energy from the oxidation of iron- and sulfur-containing minerals for growth. It thrives at extremely low pH (pH 1–2 and fixes both carbon and nitrogen from the atmosphere. It solubilizes copper and other metals from rocks and plays an important role in nutrient and metal biogeochemical cycling in acid environments. The lack of a well-developed system for genetic manipulation has prevented thorough exploration of its physiology. Also, confusion has been caused by prior metabolic models constructed based upon the examination of multiple, and sometimes distantly related, strains of the microorganism. Results The genome of the type strain A. ferrooxidans ATCC 23270 was sequenced and annotated to identify general features and provide a framework for in silico metabolic reconstruction. Earlier models of iron and sulfur oxidation, biofilm formation, quorum sensing, inorganic ion uptake, and amino acid metabolism are confirmed and extended. Initial models are presented for central carbon metabolism, anaerobic metabolism (including sulfur reduction, hydrogen metabolism and nitrogen fixation, stress responses, DNA repair, and metal and toxic compound fluxes. Conclusion Bioinformatics analysis provides a valuable platform for gene discovery and functional prediction that helps explain the activity of A. ferrooxidans in industrial bioleaching and its role as a primary producer in acidic environments. An analysis of the genome of the type strain provides a coherent view of its gene content and metabolic potential.

  3. Genes and pathways for CO2 fixation in the obligate, chemolithoautotrophic acidophile, Acidithiobacillus ferrooxidans, Carbon fixation in A. ferrooxidans

    Directory of Open Access Journals (Sweden)

    Esparza Mario

    2010-08-01

    Full Text Available Abstract Background Acidithiobacillus ferrooxidans is chemolithoautotrophic γ-proteobacterium that thrives at extremely low pH (pH 1-2. Although a substantial amount of information is available regarding CO2 uptake and fixation in a variety of facultative autotrophs, less is known about the processes in obligate autotrophs, especially those living in extremely acidic conditions, prompting the present study. Results Four gene clusters (termed cbb1-4 in the A. ferrooxidans genome are predicted to encode enzymes and structural proteins involved in carbon assimilation via the Calvin-Benson-Bassham (CBB cycle including form I of ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO, EC 4.1.1.39 and the CO2-concentrating carboxysomes. RT-PCR experiments demonstrated that each gene cluster is a single transcriptional unit and thus is an operon. Operon cbb1 is divergently transcribed from a gene, cbbR, encoding the LysR-type transcriptional regulator CbbR that has been shown in many organisms to regulate the expression of RubisCO genes. Sigma70-like -10 and -35 promoter boxes and potential CbbR-binding sites (T-N11-A/TNA-N7TNA were predicted in the upstream regions of the four operons. Electrophoretic mobility shift assays (EMSAs confirmed that purified CbbR is able to bind to the upstream regions of the cbb1, cbb2 and cbb3 operons, demonstrating that the predicted CbbR-binding sites are functional in vitro. However, CbbR failed to bind the upstream region of the cbb4 operon that contains cbbP, encoding phosphoribulokinase (EC 2.7.1.19. Thus, other factors not present in the assay may be required for binding or the region lacks a functional CbbR-binding site. The cbb3 operon contains genes predicted to encode anthranilate synthase components I and II, catalyzing the formation of anthranilate and pyruvate from chorismate. This suggests a novel regulatory connection between CO2 fixation and tryptophan biosynthesis. The presence of a form II Rubis

  4. Influence of process variables on biooxidation of ferrous sulfate by an indigenous Acidithiobacillus ferrooxidans. Part I: Flask experiments

    Energy Technology Data Exchange (ETDEWEB)

    S.M. Mousavi; S. Yaghmaei; F. Salimi; A. Jafari [Sharif University of Technology, Tehran (Iran). Department of Chemical and Petroleum Engineering

    2006-12-15

    Biological oxidation of ferrous sulfate by Acidithiobacillus ferrooxidans has proved to be a significant step in the bioleaching of sulfide minerals and the treatment of acid mine drainage. The same bioreaction also has beneficial applications in the desulphurization of coal and removal of hydrogen sulfide from gaseous effluents. In this research, the effects of some process variables such as pH, temperature, elemental sulfur, amount of initial ferrous and magnesium ions on oxidation of ferrous sulfate by a native A. ferrooxidans, which was isolated from a chalcopyrite concentrate, were investigated. All experiments carried out in shake flasks at 33{sup o}C that was obtained as optimum temperature for the specific bacterial growth rate. The optimum range of pH for the maximum growth of the cells and effective biooxidation of ferrous sulfate varied from 2 to 2.3. The maximum biooxidation rate was achieved 1.2 g/L h in a culture initially containing 20.2 g/L Fe{sup 2+}. Mg{sup 2+} from 20 mg/L to 120 mg/L did not have any effect on the efficiency of the process, while the presence of elemental sulfur had negative effect on the biooxidation. 16 refs., 8 figs.

  5. PERFORMANCE OF A BIOTRICKLING FILTER EMPLOYING THIOBACILLUS THIOPARUS IMMOBILIZED ON POLYURETHANE FOAM FOR HYDROGEN SULFIDE REMOVAL

    Directory of Open Access Journals (Sweden)

    N. Abdehagh

    2011-09-01

    Full Text Available The removal of hydrogen sulfide (H2S from contaminated airstream was studied in a biotrickling filter (BTF packed with open-pore polyurethane foam as a carrier of Thiobacillus thioparus (DSMZ5368 with counter current gas/liquid flows. The effect of operating parameters on BTF performance was studied. Experiments were performed at different Empty Bed Residence Times (EBRT from 9 to 45 seconds, and different initial H2S concentration from 25 to 85 ppm. The results showed reasonable performance of the BTF, in H2S removal from the synthetic gas stream. However, the performance was somewhat lower than other studies in BTF in which either Thiobacillus thioparus with other packings or polyurethane foam with other microbial cultures were used. The effect of liquid recirculation rate (LRR in the range of 175-525 ml/min (0.46-1.34 m/h on BTF performance was also studied. Results showed that increasing LRR from 175 to 350 mL/min resulted in significant enhancement of H2S removal efficiency, but further increase in LRR up to 525 mL/min had an insignificant effect. H2S elimination at different heights of the bed was studied and it was found that decrease in EBRT results in more homogeneous removal of the pollutant in BTF. Determination of microbial species in the BTF after 100 days performance showed that during BTF operation the only H2S degrading specie was Thiobacillus thioparus.

  6. The small heat shock proteins from Acidithiobacillus ferrooxidans: gene expression, phylogenetic analysis, and structural modeling

    Directory of Open Access Journals (Sweden)

    Ribeiro Daniela A

    2011-12-01

    Full Text Available Abstract Background Acidithiobacillus ferrooxidans is an acidophilic, chemolithoautotrophic bacterium that has been successfully used in metal bioleaching. In this study, an analysis of the A. ferrooxidans ATCC 23270 genome revealed the presence of three sHSP genes, Afe_1009, Afe_1437 and Afe_2172, that encode proteins from the HSP20 family, a class of intracellular multimers that is especially important in extremophile microorganisms. Results The expression of the sHSP genes was investigated in A. ferrooxidans cells submitted to a heat shock at 40°C for 15, 30 and 60 minutes. After 60 minutes, the gene on locus Afe_1437 was about 20-fold more highly expressed than the gene on locus Afe_2172. Bioinformatic and phylogenetic analyses showed that the sHSPs from A. ferrooxidans are possible non-paralogous proteins, and are regulated by the σ32 factor, a common transcription factor of heat shock proteins. Structural studies using homology molecular modeling indicated that the proteins encoded by Afe_1009 and Afe_1437 have a conserved α-crystallin domain and share similar structural features with the sHSP from Methanococcus jannaschii, suggesting that their biological assembly involves 24 molecules and resembles a hollow spherical shell. Conclusion We conclude that the sHSPs encoded by the Afe_1437 and Afe_1009 genes are more likely to act as molecular chaperones in the A. ferrooxidans heat shock response. In addition, the three sHSPs from A. ferrooxidans are not recent paralogs, and the Afe_1437 and Afe_1009 genes could be inherited horizontally by A. ferrooxidans.

  7. Interaction of Acidithiobacillus ferrooxidans, Rhizobium phaseoli and Rhodotorula sp. in bioleaching process based on Lotka–Volterra model

    Directory of Open Access Journals (Sweden)

    Xuecheng Zheng

    2016-07-01

    Conclusion: The relationship among microorganisms during leaching could be described appropriately by Lotka–Volterra model between the initial and peak values. The relationship of A. ferrooxidans and R. phaseoli could be considered as mutualism, whereas, the relationship of A. ferrooxidans and R. phaseoli could be considered as commensalism.

  8. Surface Chemical Characterisation of Pyrite Exposed to Acidithiobacillus ferrooxidans and Associated Extracellular Polymeric Substances

    Directory of Open Access Journals (Sweden)

    Sian M. La Vars

    2018-03-01

    Full Text Available A. ferrooxidans and their metabolic products have previously been explored as a viable alternative depressant of pyrite for froth flotation; however, the mechanism by which separation is achieved is not completely understood. Scanning electron microscopy (SEM, photoemission electron microscopy (PEEM, time-of-flight secondary ion mass spectrometry (ToF-SIMS and captive bubble contact angle measurements have been used to examine the surface physicochemical properties of pyrite upon exposure to A. ferrooxidans grown in HH medium at pH 1.8. C K-edge near edge X-ray absorption fine structure (NEXAFS spectra collected from PEEM images indicate hydrophilic lipids, fatty acids and biopolymers are formed at the mineral surface during early exposure. After 168 h, the spectra indicate a shift towards protein and DNA, corresponding to an increase in cell population and biofilm formation on the surface, as observed by SEM. The Fe L-edge NEXAFS show gradual oxidation of the mineral surface from Fe(II sulfide to Fe(III oxyhydroxides. The oxidation of the iron species at the pyrite surface is accelerated in the presence of A. ferrooxidans and extracellular polymeric substances (EPS as compared to HH medium controls. The surface chemical changes induced by the interaction with A. ferrooxidans show a significant decrease in surface hydrophobicity within the first 2 h of exposure. The implications of these findings are the potential use of EPS produced during early attachment of A. ferrooxidans, as a depressant for bioflotation.

  9. Type IV pili of Acidithiobacillus ferrooxidans can transfer electrons from extracellular electron donors.

    Science.gov (United States)

    Li, Yongquan; Li, Hongyu

    2014-03-01

    Studies on Acidithiobacillus ferrooxidans accepting electrons from Fe(II) have previously focused on cytochrome c. However, we have discovered that, besides cytochrome c, type IV pili (Tfp) can transfer electrons. Here, we report conduction by Tfp of A. ferrooxidans analyzed with a conducting-probe atomic force microscope (AFM). The results indicate that the Tfp of A. ferrooxidans are highly conductive. The genome sequence of A. ferrooxidans ATCC 23270 contains two genes, pilV and pilW, which code for pilin domain proteins with the conserved amino acids characteristic of Tfp. Multiple alignment analysis of the PilV and PilW (pilin) proteins indicated that pilV is the adhesin gene while pilW codes for the major protein element of Tfp. The likely function of Tfp is to complete the circuit between the cell surface and Fe(II) oxides. These results indicate that Tfp of A. ferrooxidans might serve as biological nanowires transferring electrons from the surface of Fe(II) oxides to the cell surface. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Identification and Analysis of a Novel Gene Cluster Involves in Fe2+ Oxidation in Acidithiobacillus ferrooxidans ATCC 23270, a Typical Biomining Acidophile.

    Science.gov (United States)

    Ai, Chenbing; Liang, Yuting; Miao, Bo; Chen, Miao; Zeng, Weimin; Qiu, Guanzhou

    2018-07-01

    Iron-oxidizing Acidithiobacillus spp. are applied worldwide in biomining industry to extract metals from sulfide minerals. They derive energy for survival through Fe 2+ oxidation and generate Fe 3+ for the dissolution of sulfide minerals. However, molecular mechanisms of their iron oxidation still remain elusive. A novel two-cytochrome-encoding gene cluster (named tce gene cluster) encoding a high-molecular-weight cytochrome c (AFE_1428) and a c 4 -type cytochrome c 552 (AFE_1429) in A. ferrooxidans ATCC 23270 was first identified in this study. Bioinformatic analysis together with transcriptional study showed that AFE_1428 and AFE_1429 were the corresponding paralog of Cyc2 (AFE_3153) and Cyc1 (AFE_3152) which were encoded by the extensively studied rus operon and had been proven involving in ferrous iron oxidation. Both AFE_1428 and AFE_1429 contained signal peptide and the classic heme-binding motif(s) as their corresponding paralog. The modeled structure of AFE_1429 showed high resemblance to Cyc1. AFE_1428 and AFE_1429 were preferentially transcribed as their corresponding paralogs in the presence of ferrous iron as sole energy source as compared with sulfur. The tce gene cluster is highly conserved in the genomes of four phylogenetic-related A. ferrooxidans strains that were originally isolated from different sites separated with huge geographical distance, which further implies the importance of this gene cluster. Collectively, AFE_1428 and AFE_1429 involve in Fe 2+ oxidation like their corresponding paralog by integrating with the metalloproteins encoded by rus operon. This study provides novel insights into the Fe 2+ oxidation mechanism in Fe 2+ -oxidizing A. ferrooxidans ssp.

  11. Bioleaching of two different types of chalcopyrite by Acidithiobacillus ferrooxidans

    Science.gov (United States)

    Dong, Ying-bo; Lin, Hai; Fu, Kai-bin; Xu, Xiao-fang; Zhou, Shan-shan

    2013-02-01

    Two different types of chalcopyrite (pyritic chalcopyrite and porphyry chalcopyrite) were bioleached with Acidithiobacillus ferrooxidans ATF6. The bioleaching of the pyritic chalcopyrite and porphyry chalcopyrite is quite different. The copper extraction reaches 46.96% for the pyritic chalcopyrite after 48-d leaching, but it is only 14.50% for the porphyry chalcopyrite. Proper amounts of initial ferrous ions can improve the efficiency of copper extraction for the two different types of chalcopyrite. The optimum dosage of ferrous ions for the pyritic chalcopyrite and porphyry chalcopyrite is different. The adsorption of ATF6 on the pyritic chalcopyrite and porphyry chalcopyrite was also studied in this paper. It is found that ATF6 is selectively adsorbed by the two different types of chalcopyrite; the higher adsorption onto the pyritic chalcopyrite than the porphyry chalcopyrite leads to the higher copper dissolution rate of the pyritic chalcopyrite. In addition, the zeta-potential of chalcopyrite before and after bioleaching further confirms that ATF6 is more easily adsorbed onto the pyritic chalcopyrite.

  12. Global transcriptional responses of Acidithiobacillus ferrooxidans Wenelen under different sulfide minerals.

    Science.gov (United States)

    Latorre, Mauricio; Ehrenfeld, Nicole; Cortés, María Paz; Travisany, Dante; Budinich, Marko; Aravena, Andrés; González, Mauricio; Bobadilla-Fazzini, Roberto A; Parada, Pilar; Maass, Alejandro

    2016-01-01

    In order to provide new information about the adaptation of Acidithiobacillus ferrooxidans during the bioleaching process, the current analysis presents the first report of the global transcriptional response of the native copper mine strain Wenelen (DSM 16786) oxidized under different sulfide minerals. Microarrays were used to measure the response of At. ferrooxidans Wenelen to shifts from iron supplemented liquid cultures (reference state) to the addition of solid substrates enriched in pyrite or chalcopyrite. Genes encoding for energy metabolism showed a similar transcriptional profile for the two sulfide minerals. Interestingly, four operons related to sulfur metabolism were over-expressed during growth on a reduced sulfur source. Genes associated with metal tolerance (RND and ATPases type P) were up-regulated in the presence of pyrite or chalcopyrite. These results suggest that At. ferrooxidans Wenelen presents an efficient transcriptional system developed to respond to environmental conditions, namely the ability to withstand high copper concentrations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Isolation of Thiobacillus spp. and its application in the removal of ...

    African Journals Online (AJOL)

    uwerhiavwe

    physiological-biochemical characteristics. Single and mixed cultures of the strains were used to carry ... The characteristics of the sludge sample. Characteristic. Te content. Method. Solid content (%). 5 ..... archaeal diversity of a mixed thermophilic bioleaching culture by. TGGE and FISH. Syst. Appl. Microbiol. 32: 501–513.

  14. The Effect of Inoculants of Thiobacillus and Aspergillus on Corn Growth

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    M. Mohammdi Aria

    2011-01-01

    Full Text Available Abstract Phosphorus (P is one of the essential macronutrients for growth and development of plant. Phosphorus is added to soil in the form of phosphatic fertilizers, part of which is utilized by plants and the remainder converted into insoluble fixed forms. Increasingly high cost of chemical fertilizers has been the major stimulus to search for an alternative, naturally-occurring, phosphate source. The researchers offered phosphorus rocks as a valuable alternative source for P. fertilizer. Unfortunately, rock phosphate is not plant available in soils with a pH greater than 6. One method to increase soluble form inorganic P is application of phosphate solublizing microorganisms and sulfur oxidizing bacteria (Thiobacillus with rock phosphate. A greenhouse experiment was carried out with two bio fertilizers (bio fertilizers santes in incubation condition in a soil with low available P on corn growth. The bio fertilizers were: rock phosphate with 20% sulfur, 15% vermicompost, Thiobacillus bacteria and Aspergillus fungi (BFS20V15 at three rates: 440 kg/ha (BF1 , 880 kg/ha (BF2, 1320kg/ha (BF3, rock phosphate with 20% sulfur, 15% vermicompost, Thiobacillus bacteria (BFS20V15 at three rates: 440 kg/ha (B1 , 880 kg/ha (B2, 1320kg/ha (B3, triple super phosphate (TSP, and control without phosphorus. In the greenhouse experiment, shoot dry matter, p uptake in plant and available p in soil were determined. The results showed that maximum yield obtained from BF3 with the shoot dry weight 7.2 g per plant and with no significant difference in relation to the triple super phosphate (7.5g at 5% level. Also highest rate p-uptake resulted from BF3. There was significant difference between treatment BF3 and TSP on p-uptake. Results indicated that it could be possible to substitute rock phosphate inoculated with sulfur-oxidizing bacteria and phosphorous-solublizing fungus for super phosphate. Keywords: Uptake-p, pH Rock phosphate, Solfur, Vermicompost

  15. Impact of solvent extraction organics on adsorption and bioleaching of A. ferrooxidans and L. ferriphilum

    Science.gov (United States)

    Hualong, Yu; Xiaorong, Liu

    2017-04-01

    Copper solvent extraction entrained and dissoluted organics (SX organics) in the raffinate during SX operation can contaminated chalcopyrite ores and influence bioleaching efficiency by raffinate recycling. The adsorption and bioleaching of A. ferrooxidans and L. ferriphilum with contaminated ores were investigated. The results showed that, A. ferrooxidans and L. ferriphilum cells could adsorb quickly on minerals, the adsorption rate on contaminated ores were 83% and 60%, respectively, larger than on uncontaminated ores. However, in the bioleaching by the two kinds of acid bacterias, contaminated ores presented a lower bioleaching efficiency.

  16. Influence oFe3+ Ions on Nitrate Removal by Autotrophic Denitrification Using Thiobacillus denitrificans

    Directory of Open Access Journals (Sweden)

    Z. Blažková

    2017-07-01

    Full Text Available he sulphur-based autotrophic denitrification process utilizing Thiobacillus denitrificans was studied experimentally as an alternative method of removing nitrates from industrial wastewater. The objective of the work was to examine the effect of ferric iron addition to the reaction mixture and determine optimal dosage for specific conditions. All experiments were carried out in anoxic batch bioreactor, and elemental sulphur was used as an electron donor. Compared to the control operation without ferric iron addition, significant increases in nitrates removal were demonstrated for the concentration of ferric iron equal to 0.1 mg L–1. However, under these conditions, increased nitrite content was detected in the reaction mixture which exceeds the limits for drinking water.

  17. Kinetic properties of ATP sulfurylase and APS kinase from Thiobacillus denitrificans.

    Science.gov (United States)

    Gay, Sean C; Fribourgh, Jennifer L; Donohoue, Paul D; Segel, Irwin H; Fisher, Andrew J

    2009-09-01

    The Thiobacillus denitrificans genome contains two sequences corresponding to ATP sulfurylase (Tbd_0210 and Tbd_0874). Both genes were cloned and expressed protein characterized. The larger protein (Tbd_0210; 544 residues) possesses an N-terminal ATP sulfurylase domain and a C-terminal APS kinase domain and was therefore annotated as a bifunctional enzyme. But, the protein was not bifunctional because it lacked ATP sulfurylase activity. However, the enzyme did possess APS kinase activity and displayed substrate inhibition by APS. Truncated protein missing the N-terminal domain had APS kinase activity suggesting the function of the inactive sulfurylase domain is to promote the oligomerization of the APS kinase domains. The smaller gene product (Tbd_0874; 402 residues) possessed strong ATP sulfurylase activity with kinetic properties that appear to be kinetically optimized for the direction of APS utilization and ATP+sulfate production, which is consistent with an enzyme that functions physiologically to produce inorganic sulfate.

  18. Insights into the relation between adhesion force and chalcopyrite-bioleaching by Acidithiobacillus ferrooxidans.

    Science.gov (United States)

    Zhu, Jianyu; Wang, Qianfen; Zhou, Shuang; Li, Qian; Gan, Min; Jiang, Hao; Qin, Wenqing; Liu, Xueduan; Hu, Yuehua; Qiu, Guanzhou

    2015-02-01

    This paper presents a study on the relation between bacterial adhesion force and bioleaching rate of chalcopyrite, which sheds light on the influence of interfacial interaction on bioleaching behavior. In our research, Acidithiobacillus ferrooxidans (A. ferrooxidans) were adapted to grow with FeSO4 · 7H2O, element sulfur or chalcopyrite. Then, surface properties of Acidithiobacillus ferrooxidans and chalcopyrite were analyzed by contact angle, zeta potential and Fourier transform infrared spectroscopy (FTIR). Adhesion force between bacteria and chalcopyrite was measured by atomic force microscopy (AFM). Attachment and bioleaching behaviors were also monitored. The results showed that A. ferrooxidans adapted with chalcopyrite exhibited the strongest adhesion force to chalcopyrite and the highest bioleaching rate. Culture adapted with sulfur bacteria took second place and FeSO4 · 7H2O-adapted bacteria were the lowest. Bioleaching rate and bacterial attachment capacity were positively related to bacterial adhesion force, which is affected by the nature of energy source. According to this work, the attachment of bacteria to chalcopyrite surface is one of the most important aspects that influence the bioleaching process of chalcopyrite. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. A Lux-like Quorum Sensing System in the Extreme Acidophile Acidithiobacillus ferrooxidans

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    MARIELLA RIVAS

    2005-01-01

    Full Text Available The genome of the acidophilic, proteobacterium Acidithiobacillus ferrooxidans, contains linked but divergently oriented genes, termed afeI and afeR, whose predicted protein products are significantly similar to the LuxI and LuxR families of proteins. A possible promoter and Lux box are predicted upstream of afeI. A cloned copy of afeI, expressed in E. coli, encodes an enzyme that catalyzes the production of a diffusible compound identified by gas chromatography and mass spectrometry as an unsubstituted N-acyl homoserine lactone (AHL of chain length C14. This AHL can be detected by a reporter strain of Sinorhizobium meliloti Rm41 suggesting that it is biologically active. The reporter strain also responds to extracts of the supernatant of A. ferrooxidans grown to early stationary phase in sulfur medium indicating that a diffusible AHL is produced by this microorganism. Semi-quantitative RT-PCR experiments indicate that afeI and afeR are expressed maximally in early stationary phase and are more expressed when A. ferrooxidans is grown in sulfur- rather than iron-containing medium. Given the predicted amino acid sequence and functional properties of AfeI and AfeR it is proposed that A. ferrooxidans has a quorum sensing system similar to the LuxI-LuxR paradigm.

  20. Co-Inoculation Effects of Thiobacillus thiooxidans Bacteria and Mycorrhiza (Glomus spp. on Maize Nutrition at Different Levels of Sulfur

    Directory of Open Access Journals (Sweden)

    A. Gholami

    2016-02-01

    Full Text Available Introduction: Sulfur is the key element for higher crops and plays an important role in the formation of proteins, vitamins, and enzymes. It is a constituent of amino acids such as cysteine and methionine, which act for the synthesis of other compounds containing reduced sulfur, such as chlorophyll and utilization of phosphorus and otheressential nutrients.Deficiency of this nutrient in soil is usually compensated by using chemical fertilizers. However, these fertilizers have harmful effects on the environment and decrease the quality of the agriculture products. Therefore, biological fertilizers are more useful for using in agricultural ecosystems.Sulfurshould be addedto the soil, usually in a reduced form such as elemental sulfur. Use of S oxidizers enhances the rate of natural oxidation of S and speeds up the production of sulfates and makes them available to plants consequently resulting in an increased plant yield. The role of chemolithotrophic bacteria of the genus Thiobacillus through oxidation process in the soil is usually emphasized. Sulfur oxidation is the most important step of sulfur cycle, which improves soil fertility. The result is formation of sulfate, which can be used by the plants, while the acidity produced by oxidation helps to solubilize nutrients in alkaline soils. These bacteria can solubilise the soil minerals through the production of H2SO4 that reacts with these non-soluble minerals and oxidised them to be available nutrients to the cultivated plants. Arbuscular MycorrhizalFungi isan important component ofthe microbiota, mutualistic symbioticsoilfungithatcolonizesthe rootsofmost cropplants.The AM symbiosis involves an about 80% of land plant species and 92% of plant families. They have theability to enhance host uptake of relativelyimmobile nutrientsparticularly phosphorus (P andzinc (Zn,Manganese (Mn andiron(Fe.Arbuscular mycorrhizal fungi increased plant uptake of phosphorus, nitrogen and water absorption

  1. Effect of Thiobacillus thioparus 1904 and sulphur addition on odour emission during aerobic composting.

    Science.gov (United States)

    Gu, Wenjie; Sun, Wen; Lu, Yusheng; Li, Xia; Xu, Peizhi; Xie, Kaizhi; Sun, Lili; Wu, Hangtao

    2018-02-01

    The effects of sulphur and Thiobacillus thioparus 1904 on odour emissions during composting were studied. Results indicated that the sulphur addition reduced the pH and decreased cumulative emission of ammonia and the nitrogen loss by 47.80% and 44.23%, respectively, but the amount of volatile sulphur compounds (VSCs) and the sulphur loss increased. The addition of T. thioparus 1904 effectively reduced the cumulative emissions of H 2 S, methyl sulphide, methanethiol, dimethyl disulphide and the sulphur loss by 33.24%, 81.24%, 32.70%, 54.22% and 54.24%, respectively. T. thioparus 1904 also limited the nitrogen loss. The combined application of sulphur and T. thioparus 1904 resulted in the greatest amount of nitrogen retention. The accumulation of ammonia emissions was reduced by 63.33%, and the nitrogen loss was reduced by 71.93%. The combined treatment did not increase the emission of VSCs. The application of sulphur and T. thioparus 1904 may help to control the odour of compost. Copyright © 2017. Published by Elsevier Ltd.

  2. Bioleaching of Primary Nickel Ore Using Acidithiobacillus ferrooxidans LR Cells Immobilized in Glass Beads

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    Ellen Cristine Giese

    2015-06-01

    Full Text Available Sulphide minerals are one of the most important sources of value metals. For several years, a large number of hydrometallurgical and biotechnological processes have been developed to leach low-grade sulphide ores and the conditions are well established. However, the management of microorganisms in the bioleaching process is not easy to handle. In this paper, the use of immobilized cells of Acidithiobacillus ferrooxidans LR in glass beads in bioleaching of primary nickel ore was evaluated. The column experiments inoculated with immobilized cells of A. ferrooxidans LR showed the same efficiency than the conventional method using free cells and is promising for application on a larger scale as it ensuring integrity and activity of biomining microorganisms and reduce process costs. DOI: http://dx.doi.org/10.17807/orbital.v7i2.698 

  3. Formation of jarosite during Fe{sup 2+} oxidation by Acidithiobacillus ferrooxidans

    Energy Technology Data Exchange (ETDEWEB)

    Daoud, J.; Karamanev, D. [University of Western Ontario, London, ON (Canada). Dept. of Chemical & Biochemical Engineering

    2006-07-15

    Jarosite precipitation is a very important phenomenon that is observed in many bacterial cultures. In many applications involving Acidithiobacillus ferrooxidans, like coal desulphurization and bioleaching, it is crucial to minimize jarosite formation in order to increase efficiency. The formation of jarosite during the oxidation of ferrous iron by free suspended cells of A. ferrooxidans was studied. The process was studied as a function of time, pH and temperature. The main parameter affecting the jarosite formation was pH. Several experiments yielded results showing oxidation rates as high as 0.181-0.194 g/L h, with low jarosite precipitation of 0.0125-0.0209 g at conditions of pH 1.6-1.7 with an operating temperature of 35{sup o} C.

  4. Preliminary X-ray crystallographic analysis of sulfide:quinone oxidoreductase from Acidithiobacillus ferrooxidans

    International Nuclear Information System (INIS)

    Zhang, Yanfei; Cherney, Maia M.; Solomonson, Matthew; Liu, Jianshe; James, Michael N. G.; Weiner, Joel H.

    2009-01-01

    The sulfide:quinone oxidoreductase from A. ferrooxidans ATCC 23270 was overexpressed in E. coli and purified. Crystallization and preliminarily X-ray crystallographic analysis were performed for the recombinant enzyme. The gene product of open reading frame AFE-1293 from Acidithiobacillus ferrooxidans ATCC 23270 is annotated as encoding a sulfide:quinone oxidoreductase, an enzyme that catalyses electron transfer from sulfide to quinone. Following overexpression in Escherichia coli, the enzyme was purified and crystallized using the hanging-drop vapour-diffusion method. The native crystals belonged to the tetragonal space group P4 2 2 1 2, with unit-cell parameters a = b = 131.7, c = 208.8 Å, and diffracted to 2.3 Å resolution. Preliminary crystallographic analysis indicated the presence of a dimer in the asymmetric unit, with an extreme value of the Matthews coefficient (V M ) of 4.53 Å 3 Da −1 and a solvent content of 72.9%

  5. Genomic insights into the iron uptake mechanisms of the biomining microorganism Acidithiobacillus ferrooxidans.

    Science.gov (United States)

    Quatrini, Raquel; Jedlicki, Eugenia; Holmes, David S

    2005-12-01

    Commercial bioleaching of copper and the biooxidation of gold is a cost-effective and environmentally friendly process for metal recovery. A partial genome sequence of the acidophilic, bioleaching bacterium Acidithiobacillus ferrooxidans is available from two public sources. This information has been used to build preliminary models that describe how this microorganism confronts unusually high iron loads in the extremely acidic conditions (pH 2) found in natural environments and in bioleaching operations. A. ferrooxidans contains candidate genes for iron uptake, sensing, storage, and regulation of iron homeostasis. Predicted proteins exhibit significant amino acid similarity with known proteins from neutrophilic organisms, including conservation of functional motifs, permitting their identification by bioinformatics tools and allowing the recognition of common themes in iron transport across distantly related species. However, significant differences in amino acid sequence were detected in pertinent domains that suggest ways in which the periplasmic and outer membrane proteins of A. ferrooxidans maintain structural integrity and relevant protein-protein contacts at low pH. Unexpectedly, the microorganism also contains candidate genes, organized in operon-like structures that potentially encode at least 11 siderophore systems for the uptake of Fe(III), although it does not exhibit genes that could encode the biosynthesis of the siderophores themselves. The presence of multiple Fe(III) uptake systems suggests that A. ferrooxidans can inhabit aerobic environments where iron is scarce and where siderophore producers are present. It may also help to explain why it cannot tolerate high Fe(III) concentrations in bioleaching operations where it is out-competed by Leptospirillum species.

  6. Ex-situ bioremediation of U(VI from contaminated mine water using Acidithiobacillus ferrooxidans strains

    Directory of Open Access Journals (Sweden)

    Maria eRomero-Gonzalez

    2016-05-01

    Full Text Available The ex-situ bioremoval of U(VI from contaminated water using Acidithiobacillus ferrooxidans strain 8455 and 13538 was studied under a range of pH and uranium concentrations. The effect of pH on the growth of bacteria was evaluated across the range 1.5 – 4.5 pH units. The respiration rate of At. ferrooxidans at different U(VI concentrations was quantified as a measure of the rate of metabolic activity over time using an oxygen electrode. The biosorption process was quantified using a uranyl nitrate solution, U-spiked growth media and U-contaminated mine water. The results showed that both strains of At. ferrooxidans are able to remove U(VI from solution at pH 2.5 – 4.5, exhibiting a buffering capacity at pH 3.5. The respiration rate of the micro-organism was affected at U(VI concentration of 30 mg L-1. The kinetics of the sorption fitted a pseudo-first order equation, and depended on the concentration of U(VI. The KD obtained from the biosorption experiments indicated that strain 8455 is more efficient for the removal of U(VI. A bioreactor designed to treat a solution of 100 mg U(VI L-1 removed at least 50% of the U(VI in water. The study demonstrated that At. ferrooxidans can be used for the ex-situ bioremediation of U(VI contaminated mine water.

  7. Bioinformatic Prediction of Gene Functions Regulated by Quorum Sensing in the Bioleaching Bacterium Acidithiobacillus ferrooxidans

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    Alvaro Banderas

    2013-08-01

    Full Text Available The biomining bacterium Acidithiobacillus ferrooxidans oxidizes sulfide ores and promotes metal solubilization. The efficiency of this process depends on the attachment of cells to surfaces, a process regulated by quorum sensing (QS cell-to-cell signalling in many Gram-negative bacteria. At. ferrooxidans has a functional QS system and the presence of AHLs enhances its attachment to pyrite. However, direct targets of the QS transcription factor AfeR remain unknown. In this study, a bioinformatic approach was used to infer possible AfeR direct targets based on the particular palindromic features of the AfeR binding site. A set of Hidden Markov Models designed to maintain palindromic regions and vary non-palindromic regions was used to screen for putative binding sites. By annotating the context of each predicted binding site (PBS, we classified them according to their positional coherence relative to other putative genomic structures such as start codons, RNA polymerase promoter elements and intergenic regions. We further used the Multiple EM for Motif Elicitation algorithm (MEME to further filter out low homology PBSs. In summary, 75 target-genes were identified, 34 of which have a higher confidence level. Among the identified genes, we found afeR itself, zwf, genes encoding glycosyltransferase activities, metallo-beta lactamases, and active transport-related proteins. Glycosyltransferases and Zwf (Glucose 6-phosphate-1-dehydrogenase might be directly involved in polysaccharide biosynthesis and attachment to minerals by At. ferrooxidans cells during the bioleaching process.

  8. Vanadium Bioleaching Behavior by Acidithiobacillus ferrooxidans from a Vanadium-Bearing Shale

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    Dunpei Wei

    2018-01-01

    Full Text Available This study investigated bioleaching behavior of vanadium from a vanadium-bearing shale using Acidithiobacillus ferrooxidans (A. ferrooxidans. Results showed a maximum recovery of 62% vanadium in 1.2-day bioleaching, which was 22.45% higher than the controls. Then, the vanadium leaching efficiency decreased significantly, only 24% of that was obtained on the tenth day. The vanadium extraction in 1.2 days was mainly attributed to the dissolution of vanadium in free oxides of shale. Fe3+ produced by A. ferrooxidans promoted the dissolution process. X-ray diffraction (XRD patterns of the leached residues confirmed the generation of jarosite. SEM-EDS analysis of the residues indicated that jarosite adsorbed on the shale and inhibited the further dissolution of vanadium. The relevance of V, Fe, S, O was quite good in the energy disperse X-ray spectrometry (EDS element mapping of jarosite, and acid-washing of the jarosite resulted in 31.6% of the vanadium in the precipitates desorption, indicating that the decrease of vanadium leaching efficiency in bioleaching process was caused by both adsorption and co-precipitation with jarosite.

  9. Comparison Analysis of Coal Biodesulfurization and Coal’s Pyrite Bioleaching with Acidithiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    Fen-Fen Hong

    2013-01-01

    Full Text Available Acidithiobacillus ferrooxidans (A. ferrooxidans was applied in coal biodesulfurization and coal’s pyrite bioleaching. The result showed that A. ferrooxidans had significantly promoted the biodesulfurization of coal and bioleaching of coal’s pyrite. After 16 days of processing, the total sulfur removal rate of coal was 50.6%, and among them the removal of pyritic sulfur was up to 69.9%. On the contrary, after 12 days of processing, the coal’s pyrite bioleaching rate was 72.0%. SEM micrographs showed that the major pyrite forms in coal were massive and veinlets. It seems that the bacteria took priority to remove the massive pyrite. The sulfur relative contents analysis from XANES showed that the elemental sulfur (28.32% and jarosite (18.99% were accumulated in the biotreated residual coal. However, XRD and XANES spectra of residual pyrite indicated that the sulfur components were mainly composed of pyrite (49.34% and elemental sulfur (50.72% but no other sulfur contents were detected. Based on the present results, we speculated that the pyrite forms in coal might affect sulfur biooxidation process.

  10. Bioinformatic Prediction of Gene Functions Regulated by Quorum Sensing in the Bioleaching Bacterium Acidithiobacillus ferrooxidans

    Science.gov (United States)

    Banderas, Alvaro; Guiliani, Nicolas

    2013-01-01

    The biomining bacterium Acidithiobacillus ferrooxidans oxidizes sulfide ores and promotes metal solubilization. The efficiency of this process depends on the attachment of cells to surfaces, a process regulated by quorum sensing (QS) cell-to-cell signalling in many Gram-negative bacteria. At. ferrooxidans has a functional QS system and the presence of AHLs enhances its attachment to pyrite. However, direct targets of the QS transcription factor AfeR remain unknown. In this study, a bioinformatic approach was used to infer possible AfeR direct targets based on the particular palindromic features of the AfeR binding site. A set of Hidden Markov Models designed to maintain palindromic regions and vary non-palindromic regions was used to screen for putative binding sites. By annotating the context of each predicted binding site (PBS), we classified them according to their positional coherence relative to other putative genomic structures such as start codons, RNA polymerase promoter elements and intergenic regions. We further used the Multiple EM for Motif Elicitation algorithm (MEME) to further filter out low homology PBSs. In summary, 75 target-genes were identified, 34 of which have a higher confidence level. Among the identified genes, we found afeR itself, zwf, genes encoding glycosyltransferase activities, metallo-beta lactamases, and active transport-related proteins. Glycosyltransferases and Zwf (Glucose 6-phosphate-1-dehydrogenase) might be directly involved in polysaccharide biosynthesis and attachment to minerals by At. ferrooxidans cells during the bioleaching process. PMID:23959118

  11. Microarray and bioinformatic analyses suggest models for carbon metabolism in the autotroph Acidithiobacillus ferrooxidans

    Energy Technology Data Exchange (ETDEWEB)

    C. Appia-ayme; R. Quatrini; Y. Denis; F. Denizot; S. Silver; F. Roberto; F. Veloso; J. Valdes; J. P. Cardenas; M. Esparza; O. Orellana; E. Jedlicki; V. Bonnefoy; D. Holmes

    2006-09-01

    Acidithiobacillus ferrooxidans is a chemolithoautotrophic bacterium that uses iron or sulfur as an energy and electron source. Bioinformatic analysis was used to identify putative genes and potential metabolic pathways involved in CO2 fixation, 2P-glycolate detoxification, carboxysome formation and glycogen utilization in At. ferrooxidans. Microarray transcript profiling was carried out to compare the relative expression of the predicted genes of these pathways when the microorganism was grown in the presence of iron versus sulfur. Several gene expression patterns were confirmed by real-time PCR. Genes for each of the above predicted pathways were found to be organized into discrete clusters. Clusters exhibited differential gene expression depending on the presence of iron or sulfur in the medium. Concordance of gene expression within each cluster, suggested that they are operons Most notably, clusters of genes predicted to be involved in CO2 fixation, carboxysome formation, 2P-glycolate detoxification and glycogen biosynthesis were up-regulated in sulfur medium, whereas genes involved in glycogen utilization were preferentially expressed in iron medium. These results can be explained in terms of models of gene regulation that suggest how A. ferrooxidans can adjust its central carbon management to respond to changing environmental conditions.

  12. Bioflotation of sulfide minerals with Acidithiobacillus ferrooxidans in relation to copper activation and surface oxidation.

    Science.gov (United States)

    Pecina-Treviño, E T; Ramos-Escobedo, G T; Gallegos-Acevedo, P M; López-Saucedo, F J; Orrantia-Borunda, E

    2012-09-01

    Surface oxidation of sulfides and copper (Cu) activation are 2 of the main processes that determine the efficiency of flotation. The present study was developed with the intention to ascertain the role of the phenomena in the biomodification of sulfides by Acidithiobacillus ferrooxidans culture (cells and growth media) and their impact in bioflotation. Surface characteristics of chalcopyrite, sphalerite, and pyrrhotite, alone and in mixtures, after interaction with A. ferrooxidans were evaluated. Chalcopyrite floatability was increased substantially by biomodification, while bacteria depressed pyrrhotite floatability, favoring separation. The results showed that elemental sulfur concentration increased because of the oxidation generated by bacterial cells, the effect is intensified by the Fe(III) left in the culture and by galvanic contact. Acidithiobacillus ferrooxidans culture affects the Cu activation of sphalerite. The implications of elemental sulfur concentration and Cu activation of sphalerite are key factors that must be considered for the future development of sulfide bioflotation processes, since the depressive effect of cells could be counteracted by elemental sulfur generation.

  13. Comparison Analysis of Coal Biodesulfurization and Coal's Pyrite Bioleaching with Acidithiobacillus ferrooxidans

    Science.gov (United States)

    Hong, Fen-Fen; He, Huan; Liu, Jin-Yan; Tao, Xiu-Xiang; Zheng, Lei; Zhao, Yi-Dong

    2013-01-01

    Acidithiobacillus ferrooxidans (A. ferrooxidans) was applied in coal biodesulfurization and coal's pyrite bioleaching. The result showed that A. ferrooxidans had significantly promoted the biodesulfurization of coal and bioleaching of coal's pyrite. After 16 days of processing, the total sulfur removal rate of coal was 50.6%, and among them the removal of pyritic sulfur was up to 69.9%. On the contrary, after 12 days of processing, the coal's pyrite bioleaching rate was 72.0%. SEM micrographs showed that the major pyrite forms in coal were massive and veinlets. It seems that the bacteria took priority to remove the massive pyrite. The sulfur relative contents analysis from XANES showed that the elemental sulfur (28.32%) and jarosite (18.99%) were accumulated in the biotreated residual coal. However, XRD and XANES spectra of residual pyrite indicated that the sulfur components were mainly composed of pyrite (49.34%) and elemental sulfur (50.72%) but no other sulfur contents were detected. Based on the present results, we speculated that the pyrite forms in coal might affect sulfur biooxidation process. PMID:24288464

  14. Acidithrix ferrooxidans gen. nov., sp. nov.; a filamentous and obligately heterotrophic, acidophilic member of the Actinobacteria that catalyzes dissimilatory oxido-reduction of iron.

    Science.gov (United States)

    Jones, Rose M; Johnson, D Barrie

    2015-01-01

    A novel acidophilic member of the phylum Actinobacteria was isolated from an acidic stream draining an abandoned copper mine in north Wales. The isolate (PY-F3) was demonstrated to be a heterotroph that catalyzed the oxidation of ferrous iron (but not of sulfur or hydrogen) under aerobic conditions, and the reduction of ferric iron under micro-aerobic and anaerobic conditions. PY-F3 formed long entangled filaments of cells (>50 μm long) during active growth phases, though these degenerated into smaller fragments and single cells in late stationary phase. Although isolate PY-F3 was not observed to grow below pH 2.0 and 10 °C, harvested biomass was found to oxidize ferrous iron at relatively fast rates at pH 1.5 and 5 °C. Phylogenetic analysis, based on comparisons of 16S rRNA gene sequences, showed that isolate PY-F3 has 91-93% gene similarity to those of the four classified genera and species of acidophilic Actinobacteria, and therefore is a representative of a novel genus. The binomial Acidithrix ferrooxidans is proposed for this new species, with PY-F3 as the designated type strain (=DSM 28176(T), =JCM 19728(T)). Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  15. A genomic island provides Acidithiobacillus ferrooxidans ATCC 53993 additional copper resistance: a possible competitive advantage.

    Science.gov (United States)

    Orellana, Luis H; Jerez, Carlos A

    2011-11-01

    There is great interest in understanding how extremophilic biomining bacteria adapt to exceptionally high copper concentrations in their environment. Acidithiobacillus ferrooxidans ATCC 53993 genome possesses the same copper resistance determinants as strain ATCC 23270. However, the former strain contains in its genome a 160-kb genomic island (GI), which is absent in ATCC 23270. This GI contains, amongst other genes, several genes coding for an additional putative copper ATPase and a Cus system. A. ferrooxidans ATCC 53993 showed a much higher resistance to CuSO(4) (>100 mM) than that of strain ATCC 23270 (<25 mM). When a similar number of bacteria from each strain were mixed and allowed to grow in the absence of copper, their respective final numbers remained approximately equal. However, in the presence of copper, there was a clear overgrowth of strain ATCC 53993 compared to ATCC 23270. This behavior is most likely explained by the presence of the additional copper-resistance genes in the GI of strain ATCC 53993. As determined by qRT-PCR, it was demonstrated that these genes are upregulated when A. ferrooxidans ATCC 53993 is grown in the presence of copper and were shown to be functional when expressed in copper-sensitive Escherichia coli mutants. Thus, the reason for resistance to copper of two strains of the same acidophilic microorganism could be determined by slight differences in their genomes, which may not only lead to changes in their capacities to adapt to their environment, but may also help to select the more fit microorganisms for industrial biomining operations. © Springer-Verlag 2011

  16. Optimization of magnetosome production by Acidithiobacillus ferrooxidans using desirability function approach

    International Nuclear Information System (INIS)

    Yan, Lei; Zhang, Shuang; Liu, Hetao; Wang, Weidong; Chen, Peng; Li, Hongyu

    2016-01-01

    Present study aimed to resolve the conflict between cell growth and magnetosome formation of Acidithiobacillus ferrooxidans (A. ferrooxidans) in batch experiments by applying response surface methodology (RSM) integrated a desirability function approach. The effects of several operating parameters on cell growth (OD_6_0_0) and magnetosome production (C_m_a_g) were evaluated. The maximum overall desirability (D) of 0.923 was achieved at iron concentration of 125.07 mM, shake speed of 122.37 rpm and nitrogen concentration of 2.40 g/L. Correspondingly, the OD_6_0_0 and C_m_a_g were 0.522 and 1.196, respectively. The confirmation experiment confirmed that the optimum OD_6_0_0 and C_m_a_g obtained were in good agreement with the predicted values. The inductively coupled plasma atomic emission spectrometer (ICP-AES) and transmission electron microscopy (TEM) analyses revealed that the production of magnetosomes could be improved via optimization. X-ray diffraction (XRD) showed the magnetosomes are magnetite. Results indicated that RSM with a desirability function was a useful technique to get the maximum OD_6_0_0 and C_m_a_g simultaneously. - Highlights: • Optimization of magnetosome production by A. ferrooxidans using BBD of RSM. • Desirability function was used for concurrent maximization of cell and magnetosome yield. • ICP-AES results showed an increase in intracellular iron content through optimizing. • TEM showed a 2.5 fold increase in magnetosome number after optimization. • The methodology demonstrated a useful tool with an overall desirability of 0.923.

  17. Bioleaching of low grade uranium ore containing pyrite using A. ferrooxidans and A. thiooxidans

    International Nuclear Information System (INIS)

    Alexey Borisovich Umanskii; Anton Mihaylovich Klyushnikov

    2013-01-01

    A process of uranium extraction from ore containing 3.1 % pyrite by bacterial leaching was investigated in shaken flasks during 90 days. The highest uranium recovery amounting to 85.1 % was obtained using binary mixture of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans that was exceeding results obtained by traditional acid leaching technique up to 27 %. High uranium recovery was founded to be due to the high degree of pyrite dissolution that can be readily achieved by bacterial leaching (up to 98.0 %). (author)

  18. Bioleaching of low-grade uranium ore using Acidithiobacillus ferrooxidans

    International Nuclear Information System (INIS)

    Pal, S.; Das, T.; Sukla, L.B.; Roy Chaudhury, G.; Pradhan, D.

    2010-01-01

    Bioleaching of uranium was carried out with Turamdih ore sample procured from Uranium Corporation of India Limited, Jaduguda. The bacterial strain that was used in the leaching experiments was isolated from the Jaduguda mine water sample. Efficiency of bioleaching was studied by varying parameters like pulp density and initial ferrous concentration as source of energy. It is observed that the efficiency of bioleaching was 49% at 10% pulp density (w/v) and initial pH 2.0. Addition of external has no effect on efficiency of bioleaching showing domination of direct leaching mechanism over indirect. (author)

  19. Evaluating Maize Yield and the Quality of Response to Vermicompost, in Thiobacillus and Foliar Application of Fe and Zn

    Directory of Open Access Journals (Sweden)

    Elnaz Davaran Hagh

    2017-08-01

    Full Text Available Introduction Half of the world's population suffers from micronutrients malnutrition. Use of bio-fertilizers in sustainable agricultural systems is important in production and enables plants to absorb more water from soil and improves plant nutrient uptake and photosynthesis. Benefits of vermicompost application in agriculture is due to its content of organic matter, plant nutrients and plant growth promotion. Vermicompost increases the absorption and transition of nutrients from soil to roots and improves plant growth (Simsek-Ersahin, 2011. Zn and Fe application is highly important; foliar application causes faster and higher absorption rate and cures deficiencies symptoms (Ghaffari et al., 2010. Thiobacillus is a chemolithotroph bacterium, receiving energy from sulfur oxidation. This bacterium acidifies microcites in the rhizosphere, increasing the availability of nutrients to plant roots (Kaya et al., 2009. Regarding the benefits of integrated nutrient management, this experiment was conducted with the aim of testing the effects of Fe and Zn foliar spraying, Thiobacillu sthiooxidans inoculation and vermicompost application on growth, yield and bio fortification of popcorn maize. Materials and methods This experiment was conducted in 2012 at the research field of Islamic Azad University, Tabriz branch, Iran. The experiment was conducted in factorial in the form of a randomized complete block design with three replications and four factors: vermicompost application in soil (0 and 2 t.ha-1, applied in strip form below the seeds before cultivation, inoculation with Thiobacillus thiooxidans, with a population of 108cfu.g-1. Sulfur was inoculated with T. thiooxidans prior to application. Fe chelate foliar application (without spraying and two times spraying of 0.002 concentration of 13% Fe chelate and Zn chelate foliar application (without spraying and two times spraying of 0.002 concentration of 15% Zn chelate. Maize seeds (Zea mays L. var

  20. Amenability of low-grade uranium towards column bioleaching by acidithiobacillus ferrooxidans

    International Nuclear Information System (INIS)

    Abhilash; Mehta, K.D.; Kumar, V.; Pandey, B.D.; Tamrakar, P.K.

    2007-01-01

    R and D studies were carried out at NML using Acidithiobacillus ferrooxidans (Ac.Tf) in column for the bio-recovery of uranium from the low-grade uranium ore containing 0.024% U 3 O 8 of Turamdih mines, Singhbhum. A recovery of 55.48% uranium was obtained in bio-leaching as against ∼ 44.9% in sterile control in 30 days at 1.7 pH in a column containing 2.5kg ore of particle size mainly in the range 5-1mm. In the large scale column, leaching with 80kg ore of particle size ∼ 0.5cm, uranium bio-recovery was found to be 69.8% in comparison to a recovery of 55% in control set at 1.7 pH in 50 days. The uranium recoveries followed indirect leaching mechanism. (author)

  1. Synergistic bioleaching of chalcopyrite and bornite in the presence of Acidithiobacillus ferrooxidans.

    Science.gov (United States)

    Zhao, Hongbo; Wang, Jun; Hu, Minghao; Qin, Wenqing; Zhang, Yansheng; Qiu, Guanzhou

    2013-12-01

    Bioleaching of chalcopyrite and bornite in the presence of Acidithiobacillus ferrooxidans was carried out to investigate the influences between each other during bioleaching. Bioleaching results indicated that bornite accelerated the dissolution of chalcopyrite, and chalcopyrite also accelerated the dissolution of bornite, it could be described as a synergistic effect during bioleaching, this synergistic effect might be attributed to the galvanic effect between chalcopyrite and bornite, and to the relatively low solution potential as the addition of bornite. Significantly amount of elemental sulfur and jarosite formed on the minerals surface might be the main passivation film inhibiting the further dissolution, and the amount of elemental sulfur significantly increased with the addition of bornite. Results of electrochemical measurements indicated that the oxidation and reduction mechanisms of chalcopyrite and bornite were similar, the addition of bornite or chalcopyrite did not change the oxidative and reductive mechanisms, but increased the oxidation rate. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Selective separation of arsenopyrite from pyrite by biomodulation in the presence of Acidithiobacillus ferrooxidans.

    Science.gov (United States)

    Chandraprabha, M N; Natarajan, K A; Somasundaran, P

    2004-08-15

    Effective methods for selective separation using flotation or flocculation of arsenopyrite from pyrite by biomodulation using Acidithiobacillus ferrooxidans are presented here. Adhesion of the bacterium to the surface of arsenopyrite was very slow compared to that to pyrite, resulting in a difference in surface modification of the minerals subsequent to interaction with cells. The cells were able to effectively depress pyrite flotation in presence of collectors like potassium isopropyl xanthate and potassium amyl xanthate. On the other hand the flotability of arsenopyrite after conditioning with the cells was not significantly affected. The activation of pyrite by copper sulfate was reduced when the minerals were conditioned together, resulting in better selectivity. Selective separation could also be achieved by flocculation of biomodulated samples.

  3. Insights into the iron and sulfur energetic metabolism of Acidithiobacillus ferrooxidans by microarray transcriptome profiling

    Energy Technology Data Exchange (ETDEWEB)

    R. Quatrini; C. Appia-Ayme; Y. Denis; J. Ratouchniak; F. Veloso; J. Valdes; C. Lefimil; S. Silver; F. Roberto; O. Orellana; F. Denizot; E. Jedlicki; D. Holmes; V. Bonnefoy

    2006-09-01

    Acidithiobacillus ferrooxidans is a well known acidophilic, chemolithoautotrophic, Gram negative, bacterium involved in bioleaching and acid mine drainage. In aerobic conditions, it gains energy mainly from the oxidation of ferrous iron and/or reduced sulfur compounds present in ores. After initial oxidation of the substrate, electrons from ferrous iron or sulfur enter respiratory chains and are transported through several redox proteins to oxygen. However, the oxidation of ferrous iron and reduced sulfur compounds has also to provide electrons for the reduction of NAD(P) that is subsequently required for many metabolic processes including CO2 fixation. To help to unravel the enzymatic pathways and the electron transfer chains involved in these processes, a genome-wide microarray transcript profiling analysis was carried out. Oligonucleotides corresponding to approximately 3000 genes of the A. ferrooxidans type strain ATCC23270 were spotted onto glass-slides and hybridized with cDNA retrotranscribed from RNA extracted from ferrous iron and sulfur grown cells. The genes which are preferentially transcribed in ferrous iron conditions and those preferentially transcribed in sulfur conditions were analyzed. The expression of a substantial number of these genes has been validated by real-time PCR, Northern blot hybridization and/or immunodetection analysis. Our results support and extend certain models of iron and sulfur oxidation and highlight previous observations regarding the possible presence of alternate electron pathways. Our findings also suggest ways in which iron and sulfur oxidation may be co-ordinately regulated. An accompanying paper (Appia-Ayme et al.) describes results pertaining to other metabolic functions.

  4. A Tyrosine-Dependent Riboswitch Controls the Expression of a Tyrosyl-tRNA Synthetase from Acidithiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    Paula Bustamante

    2016-06-01

    Full Text Available Expression of aminoacyl-tRNA synthetases is regulated by a variety of mechanisms at the level of transcription or translation. A T-box dependent transcription termination / antitermination riboswitch system that responds to charged / uncharged tRNA regulates expression of aminoacyl tRNA synthetase genes in Gram-positive bacteria. TyrZ, the gene encoding tyrosyl-tRNA synthetase from Acidithiobacillus ferrooxidans, a Gram-negative acidophilic bacterium that participates in bioleaching of minerals, resembles the gene from Bacillus subtilis including the 5´-untranslated region encoding the riboswitch. Transcription of A. ferrooxidans tyrZ is induced by the presence of tyrosine by a mechanism involving antitermination of transcription. This mechanism is probably adapted to the low supply of amino acids of acidic environments of autotrophic bioleaching microorganisms. This work is licensed under a Creative Commons Attribution 4.0 International License.

  5. Expression, purification and molecular structure modeling of thioredoxin (Trx) and thioredoxin reductase (TrxR) from Acidithiobacillus ferrooxidans.

    Science.gov (United States)

    Wang, Yiping; Zhang, Xiaojian; Liu, Qing; Ai, Chenbing; Mo, Hongyu; Zeng, Jia

    2009-07-01

    The thioredoxin system consists of thioredoxin (Trx), thioredoxin reductase (TrxR) and NADPH, which plays several key roles in maintaining the redox environment of the cell. In Acidithiobacillus ferrooxidans, thioredoxin system may play important functions in the activity regulation of periplasmic proteins and energy metabolism. Here, we cloned thioredoxin (trx) and thioredoxin reductase (trxR) genes from Acidithiobacillus ferrooxidans, and expressed the genes in Escherichia coli. His-Trx and His-TrxR were purified to homogeneity with one-step Ni-NTA affinity column chromatography. Site-directed mutagenesis results confirmed that Cys33, Cys36 of thioredoxin, and Cys142, Cys145 of thioredoxin reductase were active-site residues.

  6. Evaluation of Thiobacillus Bacteria and Mycorrhizal Symbiosis on Yield and Yield Components of Garlic (Allium sativum at Different Levels of Sulfur

    Directory of Open Access Journals (Sweden)

    parvin Hejazi rad

    2017-09-01

    Full Text Available Introduction Most researchers believe that good management and proper use of biofertilizers are the ways for preparation of better nutritional conditions for the medicinal plant. Garlic is one of the most important medicinal crops. Allicin is the main active ingredient in this plant. Biofertilizers contain beneficial soil microorganisms or the metabolic products. Mycorrhizal symbiosis improves the soil physical, chemical and biological properties. Mycorrhizae increase crop resistance to pathogens, nutrient and water uptake, also reduce the negative effects of environmental stress and improve the quality of their host plants. Adding sulfur to the soil to improve the nutritional status of the plant by the release of nutrients will be effective when that the oxidation of sulfur in the soil is significant. For sulfur uptake by the plant, it is necessary that this element convert to sulfate by soil microorganisms. If elemental sulfur distribute in the soil and mix with the organic material, conversion of sulfur-oxidizing microorganisms be faster in wet conditions. Materials and methods The experiment was conducted as randomized complete block design with three replications in 2012. Treatments were included control plot, mycorrhizal inoculation (M, Thiobacillus (T, M + T, 75 kg sulfur per hectare (75S, 75S + M, 75S + T, 75S + M + T, 150 kg sulfur per hectare (150S, 150S + M, 150S + T, 150S + M + T. Each plot consisted of four rows with a spacing of 40 cm and row length of 10 m. In treatments with 75 and 150 kg sulfur per hectare, 48 and 96 g of sulfur were used, respectively. Thiobacillus at the recommended dose was added to the soil a week before planting. Percent of fungal colonization obtained with Gridline Intersect Method. HPLC method was used to extract allicin content. Data were analyzed with the MSTAT-C software; the means were compared with LSD test at the 5% level of probability. Results and discussion The results showed that tuber dry

  7. Hydrogen sulfide oxidation in novel Horizontal-Flow Biofilm Reactors dominated by an Acidithiobacillus and a Thiobacillus species.

    Science.gov (United States)

    Gerrity, S; Kennelly, C; Clifford, E; Collins, G

    2016-09-01

    Hydrogen Sulfide (H2S) is an odourous, highly toxic gas commonly encountered in various commercial and municipal sectors. Three novel, laboratory-scale, Horizontal-Flow Biofilm Reactors (HFBRs) were tested for the removal of H2S gas from air streams over a 178-day trial at 10°C. Removal rates of up to 15.1 g [H2S] m(-3) h(-1) were achieved, demonstrating the HFBRs as a feasible technology for the treatment of H2S-contaminated airstreams at low temperatures. Bio-oxidation of H2S in the reactors led to the production of H(+) and sulfate (SO(2-)4) ions, resulting in the acidification of the liquid phase. Reduced removal efficiency was observed at loading rates of 15.1 g [H2S] m(-3) h(-1). NaHCO3 addition to the liquid nutrient feed (synthetic wastewater (SWW)) resulted in improved H2S removal. Bacterial diversity, which was investigated by sequencing and fingerprinting 16S rRNA genes, was low, likely due to the harsh conditions prevailing in the systems. The HFBRs were dominated by two species from the genus Acidithiobacillus and Thiobacillus. Nonetheless, there were significant differences in microbial community structure between distinct HFBR zones due to the influence of alkalinity, pH and SO4 concentrations. Despite the low temperature, this study indicates HFBRs have an excellent potential to biologically treat H2S-contaminated airstreams.

  8. Role of Thiobacillus thioparus in the biodegradation of carbon disulfide in a biofilter packed with a recycled organic pelletized material.

    Science.gov (United States)

    Prenafeta-Boldú, Francesc X; Rojo, Naiara; Gallastegui, Gorka; Guivernau, Miriam; Viñas, Marc; Elías, Ana

    2014-07-01

    This study reports the biodegradation of carbon disulfide (CS2) in air biofilters packed with a pelletized mixture of composted manure and sawdust. Experiments were carried out in two lab-scale (1.2 L) biofiltration units. Biofilter B was seeded with activated sludge enriched previously on CS2-degrading biomass under batch conditions, while biofilter A was left as a negative inoculation control. This inoculum was characterized by an acidic pH and sulfate accumulation, and contained Achromobacter xylosoxidans as the main putative CS2 biodegrading bacterium. Biofilter operation start-up was unsuccessfully attempted under xerophilic conditions and significant CS2 elimination was only achieved in biofilter A upon the implementation of an intermittent irrigation regime. Sustained removal efficiencies of 90-100 % at an inlet load of up to 12 g CS2 m(-3) h(-1) were reached. The CS2 removal in this biofilter was linked to the presence of the chemolithoautotrophic bacterium Thiobacillus thioparus, known among the relatively small number of species with a reported capacity of growing on CS2 as the sole energy source. DGGE molecular profiles confirmed that this microbe had become dominant in biofilter A while it was not detected in samples from biofilter B. Conventional biofilters packed with inexpensive organic materials are suited for the treatment of low-strength CS2 polluted gases (IL biofiltration of recalcitrant compounds has been highlighted.

  9. Synthesis of argentojarosite with simulated bioleaching solutions produced by Acidithiobacillus ferrooxidans

    International Nuclear Information System (INIS)

    th Avenue, Columbus, OH 43210 (United States))" data-affiliation=" (Department of Microbiology, Ohio State University, 484 West 12th Avenue, Columbus, OH 43210 (United States))" >Mukherjee, Chiranjit; Jones, F. Sandy; Bigham, Jerry M.; th Avenue, Columbus, OH 43210 (United States))" data-affiliation=" (Department of Microbiology, Ohio State University, 484 West 12th Avenue, Columbus, OH 43210 (United States))" >Tuovinen, Olli H.

    2016-01-01

    Argentojarosite (AgFe 3 (SO 4 ) 2 (OH) 6 ) is formed as a secondary phase in Ag-catalyzed bioleaching of chalcopyrite (CuFeS 2 ), but to date very little is known about the paragenesis or characteristics of this silver-containing compound. The purpose of this study was to synthesize argentojarosite via biological oxidation of 120 mM ferrous sulfate by Acidithiobacillus ferrooxidans. Because of its toxicity to A. ferrooxidans, Ag + (as AgNO 3 ) was added to spent culture media (pH 2) after complete oxidation of ferrous sulfate. Schwertmannite (ideally Fe 8 O 8 (OH) 6 (SO 4 )) was precipitated during the iron oxidation phase, and subsequent Ag + addition resulted in the formation of argentojarosite. Contact time (8 h, 5 d, and 14 d) and Ag + concentration (0, 5, 20, and 40 mM) were used as variables in these experiments. Synthesis of argentojarosite, schwertmannite and other mineral phases was confirmed through X-ray diffraction analysis. Additional analyses of solid-phase oxidation products included elemental composition, color and specific surface area. The sample synthesized in the presence of 40 mM Ag + and with 14 d contact time yielded an X-ray diffraction pattern of well crystallized argentojarosite, and its elemental composition closely matched the calculated Ag, Fe, and S contents of ideal argentojarosite. The color and surface area of the remaining samples were influenced by the presence of residual schwertmannite. This phase remained stable over the time course of 14 d when no Ag + was present in the system. When equilibrations were extended to 42 d, partial conversion of reference schwertmannite to goethite was noted in the absence of Ag. In the presence of 20 mM or 40 mM Ag over the same time course, some formation of argentojarosite was also noted. In this case, schwertmannite was the only source of Fe and SO 4 for argentojarosite formation. - Highlights: • Iron-oxidizing bacteria were used to oxidize Fe 2+ in the absence of K + and NH 4 + .

  10. Synthesis of argentojarosite with simulated bioleaching solutions produced by Acidithiobacillus ferrooxidans

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Chiranjit [Department of Microbiology, Ohio State University, 484 West 12" t" h Avenue, Columbus, OH 43210 (United States); Jones, F. Sandy; Bigham, Jerry M. [School of Environment and Natural Resources, Ohio State University, 2021 Coffey Road, Columbus, OH 43210 (United States); Tuovinen, Olli H., E-mail: tuovinen.1@osu.edu [Department of Microbiology, Ohio State University, 484 West 12" t" h Avenue, Columbus, OH 43210 (United States)

    2016-09-01

    Argentojarosite (AgFe{sub 3}(SO{sub 4}){sub 2}(OH){sub 6}) is formed as a secondary phase in Ag-catalyzed bioleaching of chalcopyrite (CuFeS{sub 2}), but to date very little is known about the paragenesis or characteristics of this silver-containing compound. The purpose of this study was to synthesize argentojarosite via biological oxidation of 120 mM ferrous sulfate by Acidithiobacillus ferrooxidans. Because of its toxicity to A. ferrooxidans, Ag{sup +} (as AgNO{sub 3}) was added to spent culture media (pH 2) after complete oxidation of ferrous sulfate. Schwertmannite (ideally Fe{sub 8}O{sub 8}(OH){sub 6}(SO{sub 4})) was precipitated during the iron oxidation phase, and subsequent Ag{sup +} addition resulted in the formation of argentojarosite. Contact time (8 h, 5 d, and 14 d) and Ag{sup +} concentration (0, 5, 20, and 40 mM) were used as variables in these experiments. Synthesis of argentojarosite, schwertmannite and other mineral phases was confirmed through X-ray diffraction analysis. Additional analyses of solid-phase oxidation products included elemental composition, color and specific surface area. The sample synthesized in the presence of 40 mM Ag{sup +} and with 14 d contact time yielded an X-ray diffraction pattern of well crystallized argentojarosite, and its elemental composition closely matched the calculated Ag, Fe, and S contents of ideal argentojarosite. The color and surface area of the remaining samples were influenced by the presence of residual schwertmannite. This phase remained stable over the time course of 14 d when no Ag{sup +} was present in the system. When equilibrations were extended to 42 d, partial conversion of reference schwertmannite to goethite was noted in the absence of Ag. In the presence of 20 mM or 40 mM Ag over the same time course, some formation of argentojarosite was also noted. In this case, schwertmannite was the only source of Fe and SO{sub 4} for argentojarosite formation. - Highlights: • Iron-oxidizing bacteria

  11. Effect of Extracellular Polymeric Substances on Surface Properties and Attachment Behavior of Acidithiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    Qian Li

    2016-09-01

    Full Text Available Bacterial contact leaching of ores is more effective than non-contact leaching. Adhesion is the first step for leaching bacteria to form a biofilm on a mineral surface. Extracellular polymeric substances (EPS are pivotal for mediating bacterial adhesion to a substratum. In order to clarify the role of EPS, we measured the adhesion forces between chalcopyrite-, sulfur- or FeSO4·7H2O-grown cells of Acidithiobacillus ferrooxidans and chalcopyrite by an atomic force microscope (AFM before and after EPS removal. Surface properties of these cells were assessed by measurements of the contact angle, zeta potential, Fourier transform infrared spectroscopy (FTIR and acid-base titration. Bacterial attachment to chalcopyrite was monitored for 140 min. The results indicate that the EPS control the surface properties of the cells. In addition, the surface properties are decisive for adhesion. The adhesion forces and the amounts of attached cells decreased dramatically after removing EPS, which was not dependent on the preculture.

  12. Fe extraction from çayeli copper ores by bioleaching with eco freiendly acidithiobacillus ferrooxidans

    International Nuclear Information System (INIS)

    Kocadagistan, M.E.; Bayhan, Y.K.

    2017-01-01

    Recently, biological treatment; an important recovery process, has became important from the environmental and economical respects in recovery of metallic values from low-grade sulfur-bearing ores or concentrates. Bacterial ore leaching can be applied to extract heavy metals from low grade ores, industrial wastes and other materials on an industrial scale by different procedures. The main objective of this work was to investigate the dissolution of Fe from Çayeli copper ores, via a bioleaching process using Acidithiobacillus ferrooxidans. Experiments performed with batch operation in jar test equipment were conducted at different pH values, pulp densities, inoculum volumes, particle sizes, stirring conditions and operation times. The optimal parameters were found as follows; at pH 2, the pulp density; 4% (w/v), inoculum volume; 4% (v/v), stirring rate; 120 rpm and particle size; -0.053 mm for 192nd and 288th hours, at pH 2, the pulp density; 4% (w/v), inoculum volume; 5% (v/v), stirring speed; 200 rpm and particle size; -0.053 mm for 384th and 480th hours. By performing the bioleaching process under these conditions, almost 99% of the iron extent in the ore was transfer from ore into solution, however the experiments in which distilled water was used instead of modified 9K*, only 18.5% Fe efficiency was obtained. (author)

  13. [Effect of simulated inorganic anion leaching solution of electroplating sludge on the bioactivity of Acidithiobacillus ferrooxidans].

    Science.gov (United States)

    Chen, Yan; Huang, Fang; Xie, Xin-Yuan

    2014-04-01

    An Acidithiobacillus ferrooxidans strain WZ-1 (GenBank sequence number: JQ968461) was used as the research object. The effects of Cl-, NO3-, F- and 4 kinds of simulated inorganic anions leaching solutions of electroplating sludge on the bioactivity of Fe2+ oxidation and apparent respiratory rate of WZ-1 were investigated. The results showed that Cl-, NO3(-)- didn't have any influence on the bioactivity of WZ-1 at concentrations of 5.0 g x L(-1), 1.0 g x L(-1), respectively. WZ-1 showed tolerance to high levels of Cl- and NO3- (about 10.0 g x L(-1), 5.0 g x L(-1), respectively), but it had lower tolerance to F- (25 mg x L(-1)). Different kinds of simulated inorganic anions leaching solutions of electroplating sludge had significant differences in terms of their effects on bioactivity of WZ-1 with a sequence of Cl-/NO3(-)/F(-) > or = NO3(-)/F(-) > Cl-/F(-) > Cl(-)/NO3(-).

  14. Genome-enabled studies of anaerobic, nitrate-dependent iron oxidation in the chemolithoautotrophic bacterium Thiobacillus denitrificans

    Directory of Open Access Journals (Sweden)

    Harry R Beller

    2013-08-01

    Full Text Available Thiobacillus denitrificans is a chemolithoautotrophic bacterium capable of anaerobic, nitrate-dependent U(IV and Fe(II oxidation, both of which can strongly influence the long-term efficacy of in situ reductive immobilization of uranium in contaminated aquifers. We previously identified two c-type cytochromes involved in nitrate-dependent U(IV oxidation in T. denitrificans and hypothesized that c-type cytochromes would also catalyze Fe(II oxidation, as they have been found to play this role in anaerobic phototrophic Fe(II-oxidizing bacteria. Here we report on efforts to identify genes associated with nitrate-dependent Fe(II oxidation, namely (a whole-genome transcriptional studies [using FeCO3, Fe2+, and U(IV oxides as electron donors under denitrifying conditions], (b Fe(II oxidation assays performed with knockout mutants targeting primarily highly expressed or upregulated c-type cytochromes, and (c random transposon-mutagenesis studies with screening for Fe(II oxidation. Assays of mutants for 26 target genes, most of which were c-type cytochromes, indicated that none of the mutants tested were significantly defective in nitrate-dependent Fe(II oxidation. The non-defective mutants included the c1-cytochrome subunit of the cytochrome bc1 complex (complex III, which has relevance to a previously proposed role for this complex in nitrate-dependent Fe(II oxidation and to current concepts of reverse electron transfer. A transposon mutant with a disrupted gene associated with NADH:ubiquinone oxidoreductase (complex I was ~35% defective relative to the wild-type strain; this strain was similarly defective in nitrate reduction with thiosulfate as the electron donor. Overall, our results indicate that nitrate-dependent Fe(II oxidation in T. denitrificans is not catalyzed by the same c-type cytochromes involved in U(IV oxidation, nor have other c-type cytochromes yet been implicated in the process.

  15. Evaluation of the Effect of Sulfur Application and Thiobacillus on Some Soil Chemical Characteristics and Yield of Canola in Wheat-Canola Rotation System

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    H. Besharati

    2016-09-01

    Full Text Available Introduction: After soybean and palm oil, canola is third important oil seed in the world which belongs to the genus Brassicaceae, that its seeds contain about 40% oil. The per capita consumption of oil in Iran is about 14 kg, so approximately 900 thousand tons of oil will be required for each year. However, only less than 10% of this oil is produced in the country. In recent years, special attention has been paid to canola cultivation in order to increase oil production, so during recent years an apparent increase in canola cultivated lands is significant. In most of these canola cultivated lands, the soil is calcareous therefore; some available nutrients such as phosphorus, iron and zinc are less than the amounts required by plants. Increasing qualitative and quantitative yield of canola in calcareous soils is a priority to canola cultivation improvement. Sulfur plays an important role in oil content of oily seed crops. On the other hands sulfur oxidation in calcareous soils can improve some nutrients availability. The present study was designed to investigate the effect of sulfur on yield, oil content and nutrients uptake and also its impact on soil chemical properties with 8 treatments, in 3 replications. Materials and Methods: This study was conducted in Ekbatan research station in Hamedan province for 2 years as completely randomized block design with 8 treatments and 3 repetitions. The treatments were: T1: Control (Without sulfur and Thiobacillus, T2: Application of 150 kg sulfur per ha, T3: T2+ Thiobacillus inoculums (2% of applied sulfur, T4: Application of 300 kg sulfur per ha, T5: T4+ Thiobacillus inoculums (2% of applied sulfur, T6: Application of 600 kg sulfur per ha, T7: T6+ Thiobacillus inoculums (2% of applied sulfur T8: Fertilizing based on soil test without sulfur and Thiobacillus. Thiobacillus inoculant containing about 107 cells of Thiobacillus bacteria which belonged to neutrophile Thiobacilli were prepared at soil biology

  16. Effect of Vermicompost, Sulfur and Thiobacillus on Some Soil Physico-chemical Properties, Yield and Yield Components of Maize (Zea mays L. in Jovain District

    Directory of Open Access Journals (Sweden)

    Mahmmud Ahmadi

    2018-02-01

    Full Text Available Introduction The excessive use of chemical fertilizers causes environmental pollution that is led to imbalance of essential elements in agricultural production system. Organic matter application as compost in the soil can improve chemical quality and biochemical properties that increase essential elements for plant nutrition. Application of organic manure can significantly increase the soil aggregate as well. Reported that application of 7 ton ha-1 of vermicompost increased number of leaves, stem dry weight, and corn plant height as compared to control and water holding capacity increases. Sulphur in plant is near to phosphorus (0.2%. Sulphur deficiency cause severe reduction in plant growth and due to participation in protein building and its deficiency cause yellowish in younger leaves. Sulphur can be applied as elemental sulphur, with ammonium and super phosphate to the soil. Iran is situated in arid and semi arid region of the world and need to reduce the pH with sulphur application due to high pH above 8 in some parts. The aim of this research was to study the effect of above factors in yield and yield components of maize and reducing environmental pollution. Materials and Methods This research carried out at 2012 in Jovein Distract suberb of Sabzevar city. Before conducting the research soil sample were collected from 0-30 cm depth and physical and chemical properties of the soil were estimated. Treatments including sulphur, thiobacillus and vermicompost were applied to soil and well mixed with soil before sowing. Each plot consists of five rows with six m length by 80 cm from each other. Seeds were sown at the depth of five cm and 20 cm from each other. This research carried out as a factorial experiment on the basis of randomized complete block design. In this research three factors including elemental sulphur, vermicompost and thiobacillus were used with three replications. Elemental sulphur in three levels (control, 500 kg ha-1 and

  17. Reduction of arsenic content in a complex galena concentrate by Acidithiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    López Alejandro

    2004-10-01

    Full Text Available Abstract Background Bioleaching is a process that has been used in the past in mineral pretreatment of refractory sulfides, mainly in the gold, copper and uranium benefit. This technology has been proved to be cheaper, more efficient and environmentally friendly than roasting and high pressure moisture heating processes. So far the most studied microorganism in bioleaching is Acidithiobacillus ferrooxidans. There are a few studies about the benefit of metals of low value through bioleaching. From all of these, there are almost no studies dealing with complex minerals containing arsenopyrite (FeAsS. Reduction and/or elimination of arsenic in these ores increase their value and allows the exploitation of a vast variety of minerals that today are being underexploited. Results Arsenopyrite was totally oxidized. The sum of arsenic remaining in solution and removed by sampling represents from 22 to 33% in weight (yield of the original content in the mineral. The rest of the biooxidized arsenic form amorphous compounds that precipitate. Galena (PbS was totally oxidized too, anglesite (PbSO4 formed is virtually insoluble and remains in the solids. The influence of seven factors in a batch process was studied. The maximum rate of arsenic dissolution in the concentrate was found using the following levels of factors: small surface area of particle exposure, low pulp density, injecting air and adding 9 K medium to the system. It was also found that ferric chloride and carbon dioxide decreased the arsenic dissolution rate. Bioleaching kinetic data of arsenic solubilization were used to estimate the dilution rate for a continuous culture. Calculated dilution rates were relatively small (0.088–0.103 day-1. Conclusion Proper conditions of solubilization of arsenic during bioleaching are key features to improve the percentage (22 to 33% in weight of arsenic removal. Further studies are needed to determine other factors that influence specifically the

  18. Bioleaching in batch tests for improving sludge dewaterability and metal removal using Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans after cold acclimation.

    Science.gov (United States)

    Zhou, Qingyang; Gao, Jingqing; Li, Yonghong; Zhu, Songfeng; He, Lulu; Nie, Wei; Zhang, Ruiqin

    2017-09-01

    Bioleaching is a promising technology for removal of metals from sludge and improvement of its dewaterability. Most of the previous studies of bioleaching were focused on removal of metals; bioleaching in cold environments has not been studied extensively. In this study, Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans were acclimated at 15 °C and co-inoculated to explore the optimal conditions for improvement of sludge dewaterability and removal of metals by the sequencing batch reactors. The data show after 6 days of bioleaching at 15 °C, 89.6% of Zn, 72.8% of Cu and 39.4% of Pb were removed and the specific resistance to filtration (SRF) was reduced to ∼12%. In addition, the best conditions for bioleaching are an initial pH of 6, a 15% (v/v) inoculum concentration, and A. thiooxidans and A. ferrooxidans mixed in a ratio of 4:1. We found that bioleaching of heavy metals is closely related to final pH, while the sludge SRF is dominated by other factors. Bioleaching can be completed in 6 days, and the sludge dewaterability and removal of metals at 15 °C meet the requirements of most sewage treatment plants.

  19. Cross-Comparison of Leaching Strains Isolated from Two Different Regions: Chambishi and Dexing Copper Mines

    OpenAIRE

    Ngom, Baba; Liang, Yili; Liu, Xueduan

    2014-01-01

    A cross-comparison of six strains isolated from two different regions, Chambishi copper mine (Zambia, Africa) and Dexing copper mine (China, Asia), was conducted to study the leaching efficiency of low grade copper ores. The strains belong to the three major species often encountered in bioleaching of copper sulfide ores under mesophilic conditions: Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, and Leptospirillum ferriphilum. Prior to their study in bioleaching, the different...

  20. Insights into the Quorum Sensing Regulon of the Acidophilic Acidithiobacillus ferrooxidans Revealed by Transcriptomic in the Presence of an Acyl Homoserine Lactone Superagonist Analogue

    Directory of Open Access Journals (Sweden)

    Sigde Mamani

    2016-09-01

    Full Text Available While a functional quorum sensing system has been identified in the acidophilic chemolithoautotroph Acidithiobacillus ferrooxidans ATCC 23270T and shown to modulate cell adhesion to solid substrates, nothing is known about the genes it regulates. To address the question of how quorum sensing controls biofilm formation in At. ferrooxidansT, the transcriptome of this organism in conditions in which quorum sensing response is stimulated by a synthetic superagonist AHL analogue has been studied. First, the effect on biofilm formation of a synthetic AHL tetrazolic analogue, tetrazole 9c, known for its agonistic QS activity, was assessed by fluorescence and electron microscopy experiments. A faster adherence of At. ferrooxidansT cells on sulfur coupons was observed. Then, tetrazole 9c was used in DNA microarray experiments that allowed the identification of genes regulated by quorum sensing signalling, and more particularly, those involved in early biofilm formation. Interestingly, afeI gene, encoding the AHL synthase, but not the At. ferrooxidans quorum sensing transcriptional regulator AfeR encoding gene, was shown to be regulated by quorum sensing. Data indicated that QS network represents at least 4.5 % (141 genes of the ATCC 23270T genome of which 42.5 % (60 genes are related to biofilm formation. Finally, AfeR was shown to bind specifically to the regulatory region of the afeI gene at the level of the palindromic sequence predicted to be the AfeR binding site. Our results give new insights on the response of At. ferrooxidans to quorum sensing and on biofilm biogenesis, opening new biological/chemical alternatives for bioleaching development and managing acid Mine/Rock drainage environmental damages.

  1. Biosynthesis of schwertmannite by Acidithiobacillus ferrooxidans cell suspensions under different pH condition

    Energy Technology Data Exchange (ETDEWEB)

    Liao Yuehua [Department of Environmental Engineering, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Zhou Lixiang [Department of Environmental Engineering, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China)], E-mail: lxzhou@njau.edu.cn; Liang Jianru; Xiong Huixin [Department of Environmental Engineering, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China)

    2009-01-01

    Oxidation of FeSO{sub 4} solution with initial pH in the range of 1.40-3.51 by Acidithiobacillus ferrooxidans LX5 cell at 26 deg. C and subsequent precipitation of resulting Fe(III) were investigated in the present study. Results showed that the oxidation rate of Fe(II) was around 1.2-3.9 mmol l{sup -1} h{sup -1}. X-ray diffraction (XRD) indicated that the formed precipitates were composed of natrojarosite with schwertmannite when the initial pH was 3.51, while only schwertmannite was produced when initial pH was in the range of 1.60-3.44 and no precipitate occurred when initial pH {<=} 1.40. Scanning electron microscope (SEM) analyses showed that precipitates formed in solution with initial pH 3.51 were spherical particles of about 0.4 {mu}m in diameter and had a smooth surface, whereas precipitates in solution with initial pH {<=} 3.44 were spherical particles of approximately 1.0 {mu}m in diameter, having specific sea-urchin morphology. Specific surface area of the precipitates varied from 3.42 to 23.45 m{sup 2} g{sup -1}. X-ray fluorescence analyses revealed that schwertmannite formed in solution with initial pH in the range of 2.00-3.44 had similar elemental composition and could be expressed as Fe{sub 8}O{sub 8}(OH){sub 4.42}(SO{sub 4}){sub 1.79,} whereas Fe{sub 8}O{sub 8}(OH){sub 4.36}(SO{sub 4}){sub 1.82} and Fe{sub 8}O{sub 8}(OH){sub 4.29}(SO{sub 4}){sub 1.86} as its chemical formula when the initial pH was 1.80 and 1.60, respectively.

  2. Estudo da oxidação dos sulfetos sintéticos molibdenita (MoS2 e covelita (CuS por Acidithiobacillus ferrooxidans via respirometria celular Oxidation study of the synthetic sulfides molybdenite (MoS2 and covellite (CuS by Acidithiobacillus ferrooxidans using respirometric experiments

    Directory of Open Access Journals (Sweden)

    Wilmo E. Francisco Junior

    2009-01-01

    Full Text Available This paper analyses the oxidation of covellite and molybdenite by Acidithiobacillus ferrooxidans strain LR using respirometric experiments. The results showed that both sulfides were oxidized by A. ferrooxidans, however, the covellite oxidation was much higher than molybdenite. Regarding the kinetic oxidation, the findings revealed that just molybdenite oxidation followed the classical Michaelis-Menten kinetic. It is probably associated with the pathway which these sulfides react to chemistry-bacterial attack, what is influenced by its electronic structures. Besides, experiments conducted in the presence of Fe3+ did not indicate alterations in molybdenite oxidation. Thus, ferric ions seem not to be essential to the sulfide oxidations.

  3. Adaptación de una cepa compatible con Acidithiobacillus ferrooxidans sobre concentrados de calcopirita (CuFeS2, esfalerita (ZnS y galena (PbS

    Directory of Open Access Journals (Sweden)

    E Mejía

    2011-01-01

    In this study the adaptation of Acidithiobacillus ferrooxidans-like to high concentrations of chalcopyrite, sphalerite and galena were evaluated with two mineral-particle sizes: 200 and 325 Tyler mesh. The strain was adapted using two simultaneous processes. The first one consisted in a gradual decreasing of the main energy source, ferrous sulphate. The second one consisted in a gradual increasing of the mineral content. Finally, a test was made without ferrous sulphate. The serial subculturing was found to be an efficient strategy to adapt Acidithiobacillus ferrooxidans-like to higher concentrations of chalcopyrite, sphalerite and galena. This indicates that a suitable protocol was employed. The results showed that Acidithiobacillus ferrooxidans-like is more resistant to high concentration of sphalerite, chalcopyrite and galena in descendant order. The particle size played an important role in the adaption of microorganism to the mineral. Key words: Sphalerite, chalcopyrite, galena, adapting, Acidithiobacillus ferrooxidans, bioleaching.

  4. Cross-Comparison of Leaching Strains Isolated from Two Different Regions: Chambishi and Dexing Copper Mines

    Directory of Open Access Journals (Sweden)

    Baba Ngom

    2014-01-01

    Full Text Available A cross-comparison of six strains isolated from two different regions, Chambishi copper mine (Zambia, Africa and Dexing copper mine (China, Asia, was conducted to study the leaching efficiency of low grade copper ores. The strains belong to the three major species often encountered in bioleaching of copper sulfide ores under mesophilic conditions: Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, and Leptospirillum ferriphilum. Prior to their study in bioleaching, the different strains were characterized and compared at physiological level. The results revealed that, except for copper tolerance, strains within species presented almost similar physiological traits with slight advantages of Chambishi strains. However, in terms of leaching efficiency, native strains always achieved higher cell density and greater iron and copper extraction rates than the foreign microorganisms. In addition, microbial community analysis revealed that the different mixed cultures shared almost the same profile, and At. ferrooxidans strains always outcompeted the other strains.

  5. Effect of pH values on the extracellular polysaccharide secreted by Acidithiobacillus ferrooxidans during chalcopyrite bioleaching

    Science.gov (United States)

    Yu, Run-lan; Liu, Jing; Tan, Jian-xi; Zeng, Wei-min; Shi, Li-juan; Gu, Guo-hua; Qin, Wen-qing; Qiu, Guan-zhou

    2014-04-01

    The pH value plays an important role in the bioleaching of sulphide minerals. The effect of pH values on the extracellular polysaccharide secreted by Acidithiobacillus ferrooxidans was investigated in different phases of bacterial growth during chalcopyrite bioleaching. It is found that extracellular polysaccharide secretion from the cells attached to chalcopyrite is more efficiently than that of the free cells in the bioleaching solution. Three factors, pH values, the concentration of soluble metal ions, and the bacterial growth and metabolism, affect extracellular polysaccharide secretion in the free cells, and are related to the bacterial growth phase. Extracellular polysaccharide secretion from the attached cells is mainly dependent on the pH value of the bacterial culture.

  6. Characterization of bornite (Cu5FeS4 electrodes in the presence of the bacterium Acidithiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    Bevilaqua Denise

    2003-01-01

    Full Text Available Bornite electrodes were characterized in the absence or in the presence of Acidithiobacillus ferrooxidans, which is an important microorganism involved in metal bioleaching processes. The presence of the bacterium modified the mineral/electrolyte interface, increasing the corrosion rate, as revealed by interferometric, AEM, ICP and EIS analyses. As a consequence of bacterial activity the electrode became porous, increasing its surface heterogeneity. This behavior was correlated with the evolution of impedance diagrams obtained during the time course of experiments. The main difference in these diagrams was the presence of an inductive feature (up to 44 h, which was related to bacterial action on the mineral dissolution, better than to its adhesion on the bornite. The total real impedance measured in presence of the bacterium was about 10 times lower than in its absence, due to the acceleration of the mineral dissolution, because an oxidant environment was maintained.

  7. Crystallization and preliminary crystallographic studies of FoxE from Rhodobacter ferrooxidans SW2, an FeII oxidoreductase involved in photoferrotrophy

    International Nuclear Information System (INIS)

    Pereira, L.; Saraiva, I. H.; Coelho, R.; Newman, D. K.; Louro, R. O.; Frazão, C.

    2012-01-01

    Crystals of the R. ferrooxidans SW2 iron oxidoreductase FoxE were obtained and the phase problem was solved by Fe SAD at 2.44 Å resolution. FoxE is a protein encoded by the foxEYZ operon of Rhodobacter ferrooxidans SW2 that is involved in Fe II -based anoxygenic photosynthesis (‘photoferrotrophy’). It is thought to reside in the periplasm, where it stimulates light-dependent Fe II oxidation. It contains 259 residues, including two haem c-binding motifs. As no three-dimensional model is available and there is no structure with a similar sequence, crystals of FoxE were produced. They diffracted to 2.44 Å resolution using synchrotron radiation at the Fe edge. The phase problem was solved by SAD using SHELXC/D/E and the experimental maps confirmed the presence of two haems per molecule

  8. AHL signaling molecules with a large acyl chain enhance biofilm formation on sulfur and metal sulfides by the bioleaching bacterium Acidithiobacillus ferrooxidans.

    Science.gov (United States)

    González, Alex; Bellenberg, Sören; Mamani, Sigde; Ruiz, Lina; Echeverría, Alex; Soulère, Laurent; Doutheau, Alain; Demergasso, Cecilia; Sand, Wolfgang; Queneau, Yves; Vera, Mario; Guiliani, Nicolas

    2013-04-01

    Biofilm formation plays a pivotal role in bioleaching activities of bacteria in both industrial and natural environments. Here, by visualizing attached bacterial cells on energetic substrates with different microscopy techniques, we obtained the first direct evidence that it is possible to positively modulate biofilm formation of the extremophilic bacterium Acidithiobacillus ferrooxidans on sulfur and pyrite surfaces by using Quorum Sensing molecules of the N-acylhomoserine lactone type (AHLs). Our results revealed that AHL-signaling molecules with a long acyl chain (12 or 14 carbons) increased the adhesion of A. ferrooxidans cells to these substrates. In addition, Card-Fish experiments demonstrated that C14-AHL improved the adhesion of indigenous A. ferrooxidans cells from a mixed bioleaching community to pyrite. Finally, we demonstrated that this improvement of cell adhesion is correlated with an increased production of extracellular polymeric substances. Our results open up a promising means to develop new strategies for the improvement of bioleaching efficiency and metal recovery, which could also be used to control environmental damage caused by acid mine/rock drainage.

  9. Investigation of Acidithiobacillus ferrooxidans in pure and mixed-species culture for bioleaching of Theisen sludge from former copper smelting.

    Science.gov (United States)

    Klink, C; Eisen, S; Daus, B; Heim, J; Schlömann, M; Schopf, S

    2016-06-01

    The aim of this study was to investigate the potential of bioleaching for the treatment of an environmentally hazardous waste, a blast-furnace flue dust designated Theisen sludge. Bioleaching of Theisen sludge was investigated at acidic conditions with Acidithiobacillus ferrooxidans in pure and mixed-species culture with Acidiphilium. In shaking-flask experiments, bioleaching parameters (pH, redox potential, zinc extraction from ZnS, ferrous- and ferric-iron concentration) were controlled regularly. The analysis of the dissolved metals showed that 70% zinc and 45% copper were extracted. Investigations regarding the arsenic and antimony species were performed. When iron ions were lacking, animonate (Sb(V)) and total arsenic concentration were highest in solution. The bioleaching approach was scaled up in stirred-tank bioreactors resulting in higher leaching efficiency of valuable trace elements. Concentrations of dissolved antimony were approx. 23 times, and of cobalt, germanium, and rhenium three times higher in comparison to shaking-flask experiments, when considering the difference in solid load of Theisen sludge. The extraction of base and trace metals from Theisen sludge, despite of its high content of heavy metals and organic compounds, was feasible with iron-oxidizing acidophilic bacteria. In stirred-tank bioreactors, the mixed-species culture performed better. To the best of our knowledge, this study is the first providing an appropriate biological technology for the treatment of Theisen sludge to win valuable elements. © 2016 The Society for Applied Microbiology.

  10. Oxidation of dibenzothiophene as a model substrate for the removal of organic sulphur from fossil fuels by iron(III ions generated from pyrite by Acidithiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    VLADIMIR P. BESKOSKI

    2007-06-01

    Full Text Available Within this paper a new idea for the removal of organically bonded sulphur from fossil fuels is discussed. Dibenzothiophene (DBT was used as a model compound of organicmolecules containing sulphur. This form of (biodesulphurization was performed by an indirect mechanism in which iron(III ions generated from pyrite by Acidithiobacillus ferrooxidans performed the abiotic oxidation. The obtained reaction products, dibenzothiopene sulfoxide and dibenzothiophene sulfone, are more soluble in water than the basic substrate and the obtained results confirmed the basic hypothesis and give the posibility of continuing the experiments related to application of this (biodesulphurization process.

  11. Immobilization of Acidithiobacillus ferrooxidans on sulfonated microporous poly(styrene-divinylbenzene) copolymer with granulated activated carbon and its use in bio-oxidation of ferrous iron.

    Science.gov (United States)

    Koseoglu-Imer, Derya Yuksel; Keskinler, Bulent

    2013-01-01

    The immobilization efficiencies of Acidithiobacillus ferrooxidans cells on different immobilization matrices were investigated for biooxidation of ferrous iron (Fe(2+)) to ferric iron (Fe(3+)). Six different matrices were used such as the polyurethane foam (PUF), granular activated carbon (GAC), raw poly(styrene-divinylbenzene) copolymer (rawSDVB), raw poly(styrene-divinylbenzene) copolymer with granular activated carbon (rawSDVB-GAC), sulfonated poly(styrene-divinylbenzene) copolymer (sulfSDVB) and sulfonated poly(styrene-divinylbenzene) copolymer with granular activated carbon (sulfSDVB-GAC). The sulfSDVB-GAC polymer showed the best performance for Fe(2+) biooxidation. It was used at packed-bed bioreactor and the kinetic parameters were obtained. The highest Fe(2+) biooxidation rate (R) was found to be 4.02 g/L h at the true dilution rate (Dt) of 2.47 1/h and hydraulic retention time (τ) of 0.4 h. The sulfSDVB-GAC polymer was used for the first time as immobilization material for A. ferrooxidans for Fe(2+) biooxidation. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Synthesis and properties of ternary (K, NH4, H3O)-jarosites precipitated from Acidithiobacillus ferrooxidans cultures in simulated bioleaching solutions

    International Nuclear Information System (INIS)

    Sandy Jones, F.; Bigham, Jerry M.; Gramp, Jonathan P.; Tuovinen, Olli H.

    2014-01-01

    The purpose of this study was to synthesize a series of solid solution jarosites by biological oxidation of ferrous iron at pH 2.2–4.4 and ambient temperature in media containing mixtures of K + (0, 1, 4, 6, 12, 31 mM) and NH 4 + (6.1, 80, 160, 320 mM). The starting material was a liquid medium for Acidithiobacillus ferrooxidans comprised of 120 mM FeSO 4 solution and mineral salts at pH 2.2. Following inoculation with A. ferrooxidans, the cultures were incubated in shake flasks at 22 °C. As bacteria oxidized ferrous iron, ferric iron hydrolyzed and precipitated as jarosite-group minerals (AFe 3 (SO 4 ) 2 (OH) 6 ) and/or schwertmannite (idealized formula Fe 8 O 8 (OH) 6 (SO 4 )·nH 2 O). The precipitates were characterized by X-ray diffraction (XRD), elemental analysis, and Munsell color. Schwertmannite was the dominant mineral product at low combinations of K + (≤ 4 mM) and NH 4 + (≤ 80 mM) in the media. At higher single or combined concentrations, yellowish jarosite phases were produced, and Munsell hue provided a sensitive means of detecting minor schwertmannite in the oxidation products. Although the hydrated ionic radii of K + and NH 4 + are similar, K + greatly facilitated the formation of a jarosite phase compared to NH 4 + . Unit cell and cell volume calculations from refinements of the powder XRD patterns indicated that the jarosite phases produced were mostly ternary (K, NH 4 , H 3 O)-solid solutions that were also deficient in structural Fe, especially at low NH 4 contents. Thus, ferric iron precipitation from the simulated bioleaching systems yielded solid solutions of jarosite with chemical compositions that were dependent on the relative concentrations of K + and NH 4 + in the synthesis media. No phase separations involving discrete, end-member K-jarosite or NH 4 -jarosite were detected in the un-aged precipitates. - Highlights: • Fe(III) precipitates formed in A. ferrooxidans culture solutions were characterized. • The monovalent cation

  13. The Global Redox Responding RegB/RegA Signal Transduction System Regulates the Genes Involved in Ferrous Iron and Inorganic Sulfur Compound Oxidation of the Acidophilic Acidithiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    Danielle Moinier

    2017-07-01

    Full Text Available The chemical attack of ore by ferric iron and/or sulfuric acid releases valuable metals. The products of these reactions are recycled by iron and sulfur oxidizing microorganisms. These acidophilic chemolithotrophic prokaryotes, among which Acidithiobacillus ferrooxidans, grow at the expense of the energy released from the oxidation of ferrous iron and/or inorganic sulfur compounds (ISCs. In At. ferrooxidans, it has been shown that the expression of the genes encoding the proteins involved in these respiratory pathways is dependent on the electron donor and that the genes involved in iron oxidation are expressed before those responsible for ISCs oxidation when both iron and sulfur are present. Since the redox potential increases during iron oxidation but remains stable during sulfur oxidation, we have put forward the hypothesis that the global redox responding two components system RegB/RegA is involved in this regulation. To understand the mechanism of this system and its role in the regulation of the aerobic respiratory pathways in At. ferrooxidans, the binding of different forms of RegA (DNA binding domain, wild-type, unphosphorylated and phosphorylated-like forms of RegA on the regulatory region of different genes/operons involved in ferrous iron and ISC oxidation has been analyzed. We have shown that the four RegA forms are able to bind specifically the upstream region of these genes. Interestingly, the phosphorylation of RegA did not change its affinity for its cognate DNA. The transcriptional start site of these genes/operons has been determined. In most cases, the RegA binding site(s was (were located upstream from the −35 (or −24 box suggesting that RegA does not interfere with the RNA polymerase binding. Based on the results presented in this report, the role of the RegB/RegA system in the regulation of the ferrous iron and ISC oxidation pathways in At. ferrooxidans is discussed.

  14. The Global Redox Responding RegB/RegA Signal Transduction System Regulates the Genes Involved in Ferrous Iron and Inorganic Sulfur Compound Oxidation of the Acidophilic Acidithiobacillus ferrooxidans

    Science.gov (United States)

    Moinier, Danielle; Byrne, Deborah; Amouric, Agnès; Bonnefoy, Violaine

    2017-01-01

    The chemical attack of ore by ferric iron and/or sulfuric acid releases valuable metals. The products of these reactions are recycled by iron and sulfur oxidizing microorganisms. These acidophilic chemolithotrophic prokaryotes, among which Acidithiobacillus ferrooxidans, grow at the expense of the energy released from the oxidation of ferrous iron and/or inorganic sulfur compounds (ISCs). In At. ferrooxidans, it has been shown that the expression of the genes encoding the proteins involved in these respiratory pathways is dependent on the electron donor and that the genes involved in iron oxidation are expressed before those responsible for ISCs oxidation when both iron and sulfur are present. Since the redox potential increases during iron oxidation but remains stable during sulfur oxidation, we have put forward the hypothesis that the global redox responding two components system RegB/RegA is involved in this regulation. To understand the mechanism of this system and its role in the regulation of the aerobic respiratory pathways in At. ferrooxidans, the binding of different forms of RegA (DNA binding domain, wild-type, unphosphorylated and phosphorylated-like forms of RegA) on the regulatory region of different genes/operons involved in ferrous iron and ISC oxidation has been analyzed. We have shown that the four RegA forms are able to bind specifically the upstream region of these genes. Interestingly, the phosphorylation of RegA did not change its affinity for its cognate DNA. The transcriptional start site of these genes/operons has been determined. In most cases, the RegA binding site(s) was (were) located upstream from the −35 (or −24) box suggesting that RegA does not interfere with the RNA polymerase binding. Based on the results presented in this report, the role of the RegB/RegA system in the regulation of the ferrous iron and ISC oxidation pathways in At. ferrooxidans is discussed. PMID:28747899

  15. Synthesis and properties of ternary (K, NH{sub 4}, H{sub 3}O)-jarosites precipitated from Acidithiobacillus ferrooxidans cultures in simulated bioleaching solutions

    Energy Technology Data Exchange (ETDEWEB)

    Sandy Jones, F.; Bigham, Jerry M. [School of Environment and Natural Resources, Ohio State University, 2021 Coffey Road, Columbus, OH 43210 (United States); Gramp, Jonathan P. [Department of Microbiology, Ohio State University, 484 West 12th Avenue, Columbus, OH 43210 (United States); Tuovinen, Olli H., E-mail: tuovinen.1@osu.edu [Department of Microbiology, Ohio State University, 484 West 12th Avenue, Columbus, OH 43210 (United States)

    2014-11-01

    The purpose of this study was to synthesize a series of solid solution jarosites by biological oxidation of ferrous iron at pH 2.2–4.4 and ambient temperature in media containing mixtures of K{sup +} (0, 1, 4, 6, 12, 31 mM) and NH{sub 4}{sup +} (6.1, 80, 160, 320 mM). The starting material was a liquid medium for Acidithiobacillus ferrooxidans comprised of 120 mM FeSO{sub 4} solution and mineral salts at pH 2.2. Following inoculation with A. ferrooxidans, the cultures were incubated in shake flasks at 22 °C. As bacteria oxidized ferrous iron, ferric iron hydrolyzed and precipitated as jarosite-group minerals (AFe{sub 3}(SO{sub 4}){sub 2}(OH){sub 6}) and/or schwertmannite (idealized formula Fe{sub 8}O{sub 8}(OH){sub 6}(SO{sub 4})·nH{sub 2}O). The precipitates were characterized by X-ray diffraction (XRD), elemental analysis, and Munsell color. Schwertmannite was the dominant mineral product at low combinations of K{sup +} (≤ 4 mM) and NH{sub 4}{sup +} (≤ 80 mM) in the media. At higher single or combined concentrations, yellowish jarosite phases were produced, and Munsell hue provided a sensitive means of detecting minor schwertmannite in the oxidation products. Although the hydrated ionic radii of K{sup +} and NH{sub 4}{sup +} are similar, K{sup +} greatly facilitated the formation of a jarosite phase compared to NH{sub 4}{sup +}. Unit cell and cell volume calculations from refinements of the powder XRD patterns indicated that the jarosite phases produced were mostly ternary (K, NH{sub 4}, H{sub 3}O)-solid solutions that were also deficient in structural Fe, especially at low NH{sub 4} contents. Thus, ferric iron precipitation from the simulated bioleaching systems yielded solid solutions of jarosite with chemical compositions that were dependent on the relative concentrations of K{sup +} and NH{sub 4}{sup +} in the synthesis media. No phase separations involving discrete, end-member K-jarosite or NH{sub 4}-jarosite were detected in the un-aged precipitates

  16. FY 1994 report on the cooperative research on the biological use mine wastewater treatment technology; 1994 nendo bio riyo ni yoru kohaisui shori gijutsu ni kansuru kenkyu kyoryoku hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    In this project, a pilot plant for mine wastewater treatment facilities using Thiobacillus ferrooxidans was installed at the Wushan mine in China to study the operation using the bacteria habitable in this mine. The project aims at establishing the mine wastewater treatment technology using the method of Thiobacillus ferrooxidans in China. The field survey and study in Japan were carried out. In the field survey, the technical guidance was given for incubation method, neutralization experiment method and analysis method of Thiobacillus ferrooxidans. In the study in Japan, one kind of bacteria to be used was selected in the 'selection test for the optimum kind of bacteria,' and a study was made which was titled 'Study of mine wastewater treatment using the method of Thiobacillus ferrooxidans which is suitable for the mine site.' In 'Study of the optimum removal of heavy metal in mine wastewater,' a table test of sulfide precipitation method was conducted on copper removal/recovery to make formation conditions of copper sulfide clear. The conditions obtained were reflected in 'Study of mine wastewater treatment by the method of Thiobacillus ferrooxidans which is suitable for the mine site,' and various conditions for bacteria oxidation process were studied. The paper surveyed characteristics of heavy metal and temperature of Chinese strains. Further, the basic data were acquired which contribute to the production of inorganic flocculants. (NEDO)

  17. Mecanismo de selección de consorcios bacterianos compatibles con A. ferrooxidans y A. thiooxidans en procesos de biodesulfurización de carbón

    Directory of Open Access Journals (Sweden)

    Gerardo Andrés Caicedo

    2010-01-01

    Full Text Available A nivel de erlenmeyer, se evaluaron procesos de biodesulfurización de un carbón rico en azufre con un tamaño de partícula entre 0,24 cm - 0,06 cm, empleando consorcios bacterianos de cepas compatibles con Acidithiobacillus ferrooxidans y compatibles con Acidithiobacillus thiooxidans. Se analizaron los principales factores fisicoquímicos que pueden influir, con monitoreos de pH, potencial redox en el líquido lixiviante y sulfato en solución y precipitado, producido a partir de compuestos reducidos de azufre presentes en el carbón y en el medio. De acuerdo con los resultados obtenidos, se alcanzó 71,50% de sulfato producido con relación al máximo posible después de 16 días de proceso. Estos resultados son claves para la escogencia de cepa a la hora de trabajar procesos de biodesulfurización a escala mayor.

  18. Oxidation study of the synthetic sulfides molybdenite (MoS{sub 2}) and covellite (CuS) by acidithiobacillus ferrooxidants using respirometric experiments; Estudo da oxidacao dos sulfetos sinteticos molibdenita (MoS2) e covelita (CuS) por Acidithiobacillus ferrooxidans via respirometria celular

    Energy Technology Data Exchange (ETDEWEB)

    Francisco Junior, Wilmo E. [Universidade Federal de Rondonia (UFRO), Porto Velho, RO (Brazil). Dept. de Quimica; Universidade Estadual Paulista (UNESP), Araraquara, SP (Brazil). Inst. de Quimica. Dept. de Bioquimica e Tecnologia Quimica], e-mail: wilmojr@bol.com.br; Bevilaqua, Denise; Garcia Junior, Oswaldo [Universidade Estadual Paulista (UNESP), Araraquara, SP (Brazil). Inst. de Quimica. Dept. de Bioquimica e Tecnologia Quimica

    2009-07-01

    This paper analyses the oxidation of covellite and molybdenite by Acidithiobacillus ferrooxidans strain LR using respirometric experiments. The results showed that both sulfides were oxidized by A. ferrooxidans, however, the covellite oxidation was much higher than molybdenite. Regarding the kinetic oxidation, the findings revealed that just molybdenite oxidation followed the classical Michaelis-Menten kinetic. It is probably associated with the pathway which these sulfides react to chemistry-bacterial attack, what is influenced by its electronic structures. Besides, experiments conducted in the presence of Fe{sup 3+} did not indicate alterations in molybdenite oxidation. Thus, ferric ions seem not to be essential to the sulfide oxidations. (author)

  19. Biochemical solubilization of toxic salts from residual geothermal brines and waste waters

    Science.gov (United States)

    Premuzic, Eugene T.; Lin, Mow S.

    1994-11-22

    A method of solubilizing metal salts such as metal sulfides in a geothermal sludge using mutant Thiobacilli selected for their ability to metabolize metal salts at high temperature is disclosed, The method includes the introduction of mutated Thiobacillus ferrooxidans and Thiobacillus thiooxidans to a geothermal sludge or brine. The microorganisms catalyze the solubilization of metal salts, For instance, in the case of metal sulfides, the microorganisms catalyze the solubilization to form soluble metal sulfates.

  20. Effect of calcium oxide on the efficiency of ferrous ion oxidation and total iron precipitation during ferrous ion oxidation in simulated acid mine drainage treatment with inoculation of Acidithiobacillus ferrooxidans.

    Science.gov (United States)

    Liu, Fenwu; Zhou, Jun; Jin, Tongjun; Zhang, Shasha; Liu, Lanlan

    2016-01-01

    Calcium oxide was added into ferrous ion oxidation system in the presence of Acidithiobacillus ferrooxidans at concentrations of 0-4.00 g/L. The pH, ferrous ion oxidation efficiency, total iron precipitation efficiency, and phase of the solid minerals harvested from different treatments were investigated during the ferrous ion oxidation process. In control check (CK) system, pH of the solution decreased from 2.81 to 2.25 when ferrous ions achieved complete oxidation after 72 h of Acidithiobacillus ferrooxidans incubation without the addition of calcium oxide, and total iron precipitation efficiency reached 20.2%. Efficiency of ferrous ion oxidation and total iron precipitation was significantly improved when the amount of calcium oxide added was ≤1.33 g/L, and the minerals harvested from systems were mainly a mixture of jarosite and schwertmannite. For example, the ferrous ion oxidation efficiency reached 100% at 60 h and total iron precipitation efficiency was increased to 32.1% at 72 h when 1.33 g/L of calcium oxide was added. However, ferrous ion oxidation and total iron precipitation for jarosite and schwertmannite formation were inhibited if the amount of calcium oxide added was above 2.67 g/L, and large amounts of calcium sulfate dihydrate were generated in systems.

  1. LIXIVIACION BACTERIANA EN REACTORES: RECUPERACION DE COBRE A PARTIR DE CONCENTRADOS SULFURADOS.

    OpenAIRE

    CASAS DE PRADA, JESUS MANUEL

    1991-01-01

    Se estudió la cinética de lixiviación química (estéril) y bacteriana (con Thiobacillus ferrooxidans) de dos concentrados sulfurados de cobre, utilizando como agente oxidante el sulfato férrico en ambos casos. Los concentrados fueron suministrados por las 167p.

  2. Isolated galaxies

    International Nuclear Information System (INIS)

    Einasto, Maret

    1990-01-01

    To test for the possible presence of really isolated galaxies, which form a randomly distributed population in voids, we compare the distribution of most isolated galaxies in an observed sample with distributions of the same number of random points using the nearest neighbour test. The results show that the random population of really isolated galaxies does not exist - even the most isolated galaxies are connected with systems of galaxies, forming their outlying parts. (author)

  3. Limnobacter thiooxidans gen. nov., sp. nov., a novel thiosulfate-oxidizing bacterium isolated from freshwater lake sediment.

    Science.gov (United States)

    Spring, S; Kämpfer, P; Schleifer, K H

    2001-07-01

    Two novel thiosulfate-oxidizing strains were isolated from sediment of the littoral zone of a freshwater lake (Lake Chiemsee, Bavaria, Germany). The new isolates, designated CS-K1 and CS-K2T, were gram-negative, slightly curved rods with pointed ends that were motile by means of single polar flagella. Both strains were obligately aerobic and grew on a variety of organic substrates, but not autotrophically. The utilization of thiosulfate led to an increase in the growth yield, indicating that these strains were able to grow chemolithoheterotrophically by oxidation of thiosulfate to sulfate. The optimum thiosulfate concentrations for growth were determined to be 10 mM for strain CS-K1 and 20 mM for strain CS-K2T. Phylogenetically, both strains were affiliated to the beta-Proteobacteria. Their characterization by a polyphasic approach resulted in the placement of both strains into a single species that is related only distantly to any known type species. Thus, the creation of a novel taxon is proposed, with the name Limnobacter thiooxidans gen. nov., sp. nov., to include the novel strains. In addition, the phylogenetic position of the chemolithoheterotrophic strain 'Thiobacillus' Q was determined.

  4. Isolation World

    OpenAIRE

    Núñez Martín, Eugeni

    2012-01-01

    El trabajo de fin de grado tiene como nombre “Isolation World”, que en su traducción literal significa “Aislamiento del mundo”, un videojuego diseñado y creado desde cero en su totalidad, utilizando herramientas y conocimiento de lógica en programación que se han ido aprendiendo y desarrollando a lo largo de la carrera.

  5. Isolation of a strain of Acidithiobacillus caldus and its role in bioleaching of chalcopyrite

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Q.G.; Bo, F.; Bo, Z.H.; Xi, L.; Jian, G.; Fei, L.F.; Hua, C.X. [Central South University of Technology, Changsha (China)

    2007-09-15

    A moderately thermophilic and acidophilic sulfur-oxidizing bacterium named S-2, was isolated from coal heap drainage. The bacterium was motile, Gramnegative, rod-shaped, measured 0.4 to 0.6 by 1 to 2 gm, and grew optimally at 42-45{sup o}C and an initial pH of 2.5. The strain S-2 grew autotrophically by using elemental sulfur, sodium thiosulfate and potassium tetrathionate as energy sources. The strain did not use organic matter and inorganic minerals including ferrous sulfate, pyrite and chalcopyrite as energy sources. The morphological, biochemical, physiological characterization and analysis based on 16S rRNA gene sequence indicated that the strain S2 is most closely related to Acidithiobacillus caldus (> 99% similarity in gene sequence). The combination of the strain S-2 with Leptospirillum ferriphilum or Acidithiobacillus ferrooxidans in chalcopyrite bioleaching improved the copper-leaching efficiency. Scanning electron microscope (SEM) analysis revealed that the chalcopyrite surface in a mixed culture of Leptospirillum ferriphilum and Acidithiobacillus caldus was heavily etched. The energy dispersive X-ray (EDX) analysis indicated that Acidithiobacillus caldus has the potential role to enhance the recovery of copper from chalcopyrite by oxidizing the sulfur formed during the bioleaching progress.

  6. Bacterial leaching of uranium ores - a review

    International Nuclear Information System (INIS)

    Lowson, R.T.

    1975-11-01

    The bacterial leaching of uranium ores involves the bacterially catalysed oxidation of associated pyrite to sulphuric acid and Fe 3+ by autotrophic bacteria and the leaching of the uranium by the resulting acidic, oxidising solution. Industrial application has been limited to Thiobacillus thiooxidans and Thiobacillus ferrooxidans at pH 2 to 3, and examples of these are described. The bacterial catalysis can be improved with nutrients or prevented with poisons. The kinetics of leaching are controlled by the bed depth, particle size, percolation rate, mineralogy and temperature. Current work is aimed at quantitatively defining the parameters controlling the kinetics and extending the method to alkaline conditions with other autotrophic bacteria. (author)

  7. Underground bioleaching: extracting from low-grade ore

    International Nuclear Information System (INIS)

    McCready, R.G.L.

    1986-01-01

    In 1984, Denison Mines began a research and demonstration project on the engineering aspects of bacterial leaching of low-grade uranium ore at Elliot Lake. The leaching solution was acidic mine water enriched in bacterial nutrients and innoculated with Thiobacillus ferrooxidans. Leaching of one stope was found to be impeded by fungi of the genus penicillium. Although fungal growth on leaching stopes must be prevented, research is proceeding on the potential use of the fungi to concentrate uranium from bioleaching solutions

  8. Review biodepyritisation of coal

    Energy Technology Data Exchange (ETDEWEB)

    Acharya, C.; Sukla, L.B.; Misra, V.N. [Regional Research Lab., Orissa (India)

    2004-01-01

    This review provides a detailed summary of the recent and past research activities in the area of biodesulfurisation of coal. It provides information about microorganisms important for biodesulfurisation of coal, with the emphasis on Thiobacillus ferrooxidans. The review presents an insight into various methods of desulfurisation of coal combining physical and biological methods. Also, there are discussions on coal structure, distribution, mechanism and kinetics of pyrite oxidation and jarosite precipitation. Finally, areas requiring further research are identified.

  9. Modeling of uranium bioleaching by Acidithiobacillus ferrooxidans

    International Nuclear Information System (INIS)

    Rashidi, A.; Safdari, J.; Roosta-Azad, R.; Zokaei-Kadijani, S.

    2012-01-01

    Highlights: ► A mathematical model for the mesophilic bioleaching of uraninite is introduced. ► New rate expressions are used for the iron precipitation and uranium leaching rates. ► Good fits of the model are obtained, while the values of the parameters are within the range expected. ► The model can be applied to other bioleaching processes under the same conditions. - Abstract: In this paper, a mathematical model for the mesophilic bioleaching of uraninite is developed. The case of constant temperature, pH, and initial ore concentration is considered. The model is validated by comparing the calculated and measured values of uranium extraction, ferric and ferrous iron in solution, and cell concentration. Good fits of the model were obtained, while the values of the parameters were within the range expected. New rate expressions were used for the iron precipitation and uranium leaching rates. The rates of chemical leaching and ferric precipitation are related to the ratio of ferric to ferrous in solution. The fitted parameters can be considered applicable only to this study. In contrast, the model equation is general and can be applied to bioleaching under the same conditions.

  10. Biodegradation of Mustard

    Science.gov (United States)

    1994-07-01

    different areas of Kuwait. The isolates were identified as Asoeraillus terreus, h. IlabirM, Mucor alobosus, usarium sp . and Penicillium citrinum (94...Thiobacillus delicatus nov. sp . J. Ferment . Technol. 54:181-191 (1976). (39) Harrison, AP. The acidophilic thiobacilli and other acidophilic bacteria...methyl sulfide is oxidized to sulfate by Hnhomicrobium S sp ., Hynhomicrobu EG (21-23), Thiobacillus thioDarus TK-m and Thiobacillus MS1 (24,25), but only

  11. Optimum Shock Isolation

    National Research Council Canada - National Science Library

    Bolotnik, Nikolai

    2001-01-01

    .... Several types of performance criteria for isolation are considered, the most important of which are the peak force transmitted to the body to be isolated and the maximum displacement of the body relative to the base...

  12. Isolated patellofemoral osteoarthritis.

    NARCIS (Netherlands)

    Jonbergen, J.P.W. van; Poolman, R.W.; Kampen, A. van

    2010-01-01

    BACKGROUND AND PURPOSE: The optimal treatment for isolated patellofemoral osteoarthritis is unclear at present. We systematically reviewed the highest level of available evidence on the nonoperative and operative treatment of isolated patellofemoral osteoarthritis to develop an evidenced-based

  13. The role of heterotrophic microorganism Galactomyces sp. Z3 in improving pig slurry bioleaching.

    Science.gov (United States)

    Zhou, Jun; Zheng, Guanyu; Zhou, Lixiang; Liu, Fenwu; Zheng, Chaocheng; Cui, Chunhong

    2013-01-01

    The feasibility of removing heavy metals and eliminating pathogens from pig slurry through bioleaching involving the fungus Galactomyces sp. Z3 and two acidophilic thiobacillus (A. ferrooxidans LX5 and A. thiooxidans TS6) was investigated. It was found that the isolated pig slurry dissolved organic matter (DOM) degrader Z3 was identified as Galactomyces sp. Z3, which could grow well at pH 2.5-7 and degrade pig slurry DOM from 1973 to 942 mg/l within 48 h. During the successive multi-batch bioleaching systems, the co-inoculation of pig slurry degrader Galactomyces sp. Z3 and the two Acidithiobacillus species could improve pig slurry bioleaching efficiency compared to the single system without Galactomyces sp. Z3. The removal efficiency of Zn and Cu exceeded 94% and 85%, respectively. In addition, the elimination efficiencies of pathogens, including both total coliform and faecal coliform counts, exceeded 99% after bioleaching treatment. However, the counts of Galactomyces sp. Z3 decreased with the fall of pH and did not restore to the initial level during successive multi-batch bioleaching systems, and it is necessary to re-inoculate Galactomyces sp. Z3 cells into the bioleaching system to maintain its role in degrading pig slurry DOM. Therefore, a bioleaching technique involving both Galactomyces sp. Z3 and Acidithiobacillus species is an efficient method for removing heavy metals and eliminating pathogens from pig slurry.

  14. Mutation and premating isolation

    Science.gov (United States)

    Woodruff, R. C.; Thompson, J. N. Jr

    2002-01-01

    While premating isolation might be traceable to different genetic mechanisms in different species, evidence supports the idea that as few as one or two genes may often be sufficient to initiate isolation. Thus, new mutation can theoretically play a key role in the process. But it has long been thought that a new isolation mutation would fail, because there would be no other individuals for the isolation-mutation-carrier to mate with. We now realize that premeiotic mutations are very common and will yield a cluster of progeny carrying the same new mutant allele. In this paper, we discuss the evidence for genetically simple premating isolation barriers and the role that clusters of an isolation mutation may play in initiating allopatric, and even sympatric, species divisions.

  15. Physics in isolation

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    In late May, about 330 physicists made their way up to isolated and beautiful Lake Louise high in the Canadian Rockies about 100 miles west of Calgary in a second effort to increase interactions between particle and nuclear physicists. The conference series aims to foster exciting and diverse physics by bringing the different physicists together somewhere which is so isolated that they must interact with each other. The formula worked very well and isolated Lake Louise was a huge success

  16. Physics in isolation

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1986-09-15

    In late May, about 330 physicists made their way up to isolated and beautiful Lake Louise high in the Canadian Rockies about 100 miles west of Calgary in a second effort to increase interactions between particle and nuclear physicists. The conference series aims to foster exciting and diverse physics by bringing the different physicists together somewhere which is so isolated that they must interact with each other. The formula worked very well and isolated Lake Louise was a huge success.

  17. Isolated optic nerve pseudotumour

    International Nuclear Information System (INIS)

    Patankar, T.; Prasad, S.; Krishnan, A.; Laxminarayan, R.

    2000-01-01

    Isolated optic nerve involvement by the idiopathic inflammatory process is a rare finding and very few reports are available. Here a case of an isolated optic nerve inflammatory pseudotumour presenting with gradually progressive unilateral loss of vision is described. It showed dramatic response to a trial of steroids and its differential diagnoses are discussed. Copyright (1999) Blackwell Science Pty Ltd

  18. MOX Fabrication Isolation Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Eric L. Shaber; Bradley J Schrader

    2005-08-01

    This document provides a technical position on the preferred level of isolation to fabricate demonstration quantities of mixed oxide transmutation fuels. The Advanced Fuel Cycle Initiative should design and construct automated glovebox fabrication lines for this purpose. This level of isolation adequately protects the health and safety of workers and the general public for all mixed oxide (and other transmutation fuel) manufacturing efforts while retaining flexibility, allowing parallel development and setup, and minimizing capital expense. The basis regulations, issues, and advantages/disadvantages of five potential forms of isolation are summarized here as justification for selection of the preferred technical position.

  19. Influence of organics and silica on Fe(II) oxidation rates and cell-mineral aggregate formation by the green-sulfur Fe(II)-oxidizing bacterium Chlorobium ferrooxidans KoFox - Implications for Fe(II) oxidation in ancient oceans

    Science.gov (United States)

    Gauger, Tina; Byrne, James M.; Konhauser, Kurt O.; Obst, Martin; Crowe, Sean; Kappler, Andreas

    2016-06-01

    Most studies on microbial phototrophic Fe(II) oxidation (photoferrotrophy) have focused on purple bacteria, but recent evidence points to the importance of green-sulfur bacteria (GSB). Their recovery from modern ferruginous environments suggests that these photoferrotrophs can offer insights into how their ancient counterparts grew in Archean oceans at the time of banded iron formation (BIF) deposition. It is unknown, however, how Fe(II) oxidation rates, cell-mineral aggregate formation, and Fe-mineralogy vary under environmental conditions reminiscent of the geological past. To address this, we studied the Fe(II)-oxidizer Chlorobium ferrooxidans KoFox, a GSB living in co-culture with the heterotrophic Geospirillum strain KoFum. We investigated the mineralogy of Fe(III) metabolic products at low/high light intensity, and in the presence of dissolved silica and/or fumarate. Silica and fumarate influenced the crystallinity and particle size of the produced Fe(III) minerals. The presence of silica also enhanced Fe(II) oxidation rates, especially at high light intensities, potentially by lowering Fe(II)-toxicity to the cells. Electron microscopic imaging showed no encrustation of either KoFox or KoFum cells with Fe(III)-minerals, though weak associations were observed suggesting co-sedimentation of Fe(III) with at least some biomass via these aggregates, which could support diagenetic Fe(III)-reduction. Given that GSB are presumably one of the most ancient photosynthetic organisms, and pre-date cyanobacteria, our findings, on the one hand, strengthen arguments for photoferrotrophic activity as a likely mechanism for BIF deposition on a predominantly anoxic early Earth, but, on the other hand, also suggest that preservation of remnants of Fe(II)-oxidizing GSB as microfossils in the rock record is unlikely.

  20. isolated from Trichoderma harzianum

    African Journals Online (AJOL)

    SAM

    2014-05-21

    May 21, 2014 ... Chitinase gene from Trichoderma harzianum was cloned and hetrologously over expressed in ... used by Trichoderma to inhibit the growth of other fungi. ..... actinomycete isolates from niche habitats in Manipur for antibiotic.

  1. Biodesulfurization techniques: Application of selected microorganisms for organic sulfur removal from coals. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Elmore, B.B.

    1993-08-01

    As an alternative to post-combustion desulfurization of coal and pre-combustion desulfurization using physicochemical techniques, the microbial desulfurization of coal may be accomplished through the use of microbial cultures that, in an application of various microbial species, may remove both the pyritic and organic fractions of sulfur found in coal. Organisms have been isolated that readily depyritize coal but often at prohibitively low rates of desulfurization. Microbes have also been isolated that may potentially remove the organic-sulfur fraction present in coal (showing promise when acting on organic sulfur model compounds such as dibenzothiophene). The isolation and study of microorganisms demonstrating a potential for removing organic sulfur from coal has been undertaken in this project. Additionally, the organisms and mechanisms by which coal is microbially depyritized has been investigated. Three cultures were isolated that grew on dibenzothiophene (DBT), a model organic-sulfur compound, as the sole sulfur source. These cultures (UMX3, UMX9, and IGTS8) also grew on coal samples as the sole sulfur source. Numerous techniques for pretreating and ``cotreating`` coal for depyritization were also evaluated for the ability to improve the rate or extent of microbial depyritization. These include prewashing the coal with various solvents and adding surfactants to the culture broth. Using a bituminous coal containing 0.61% (w/w) pyrite washed with organic solvents at low slurry concentrations (2% w/v), the extent of depyritization was increased approximately 25% in two weeks as compared to controls. At slurry concentrations of 20% w/v, a tetrachloroethylene treatment of the coal followed by depyritization with Thiobacillus ferrooxidans increased both the rate and extent of depyritization by approximately 10%.

  2. Seismic isolation structure for pool-type LMFBR - isolation building with vertically isolated floor for NSSS

    International Nuclear Information System (INIS)

    Sakurai, A.; Shiojiri, H.; Aoyagi, S.; Matsuda, T.; Fujimoto, S.; Sasaki, Y.; Hirayama, H.

    1987-01-01

    The NSSS isolation floor vibration characteristics were made clear. Especially, the side support bearing (rubber bearing) is effective for horizontal floor motion restraint and rocking motion control. Seismic isolation effects for responses of the reactor components can be sufficiently expected, using the vertical seismic isolation floor. From the analytical and experimental studies, the following has been concluded: (1) Seismic isolation structure, which is suitable for large pool-type LMFBR, were proposed. (2) Seismic response characteristics of the seismic isolation structure were investigated. It was made clear that the proposed seismic isolation (Combination of the isolated building and the isolated NSSS floor) was effective. (orig./HP)

  3. Oxidation of inorganic compounds of sulphur by various sulphur bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Parker, C D; Prisk, J

    1953-01-01

    Cultures of thiobacillus thiooxidans, Th. thioparus, Th. novellus, Thiobacillus b strains t and kand Th. concretivorus, Thiobacillus x and the m strains, organisms isolated from concrete were examined to elucidate the mode of oxidation and to establish the identity of the organisms recently isolated from corroded concrete. Thiosulphate was oxidized by all these bacteria. Th. thiooxidans, Th. concretivorus and Thiobacillus x first converted it to tetrathionate and sulphate and then oxidized the tetrathionate to sulphate and free sulphuric acid. Thiobaciullus x differed from the other two in that, owing to a lesser acid tolerance, some tetrathionate was found in the final products of oxidation. Th. Thioparus converted thiosulphate to sulphate and sulphur, followed by partial oxidation of the sulphur to sulphuric acid. Th. novellus produced sulphate and sulphuric acid. Thiobacillus b, the t and k strains and the m strains formed sulphate and tetrathionate with temporary increase in pH value; only Thiobacillus x oxidized tetrationate, yielding sulphate and sulphuric acid. Elementary sulphur was oxidized by Th. thiooxidans, th. Concretivorus, thiobacillus x and Th. thioparus; the rates of oxidation decreased in that order, and the only product was sulphuric acid. Hydrogen sulphide was oxidized only at low concentrations and only by th. Concretivorus and Thiobacillus x; sulphuric acid was the end-product, and elementary sulphur may have been an intermediate. Thiobacillus x differed from Th. thiooxidans in pH range for growth and from Th. thioparus in its method of oxidation of thiosulphate, tetrathionate and H/sub 2/S. The m strains were similar to thiobacillus b and the t and k strains of trautwein.

  4. Isolated Optic Disc Tuberculosis

    Science.gov (United States)

    Mansour, Ahmad M.; Tabbara, Khalid F.; Tabbarah, Zuhair

    2015-01-01

    We present a healthy male subject who developed progressive visual loss in the left eye initially diagnosed as optic neuritis. Upon suspicion of infectious etiology, testing was positive for tuberculosis. There were no signs or symptoms of active systemic tuberculosis infection. The patient responded swiftly to antimycobacterial therapy with return of vision and resolution of disc swelling. Positive purified protein derivative skin test, negative chest radiograph, negative systemic workup, negative workup for other causes of unilateral optic neuritis and quick response to mycobacterial therapy reaffirm the entity of isolated optic disc tuberculosis similar to isolated choroidal tuberculosis without systemic manifestation. PMID:26483675

  5. Isolated Optic Disc Tuberculosis

    Directory of Open Access Journals (Sweden)

    Ahmad M. Mansour

    2015-09-01

    Full Text Available We present a healthy male subject who developed progressive visual loss in the left eye initially diagnosed as optic neuritis. Upon suspicion of infectious etiology, testing was positive for tuberculosis. There were no signs or symptoms of active systemic tuberculosis infection. The patient responded swiftly to antimycobacterial therapy with return of vision and resolution of disc swelling. Positive purified protein derivative skin test, negative chest radiograph, negative systemic workup, negative workup for other causes of unilateral optic neuritis and quick response to mycobacterial therapy reaffirm the entity of isolated optic disc tuberculosis similar to isolated choroidal tuberculosis without systemic manifestation.

  6. Primary isolated hepatic tuberculosis

    International Nuclear Information System (INIS)

    Sheikh, A.S.F.; Qureshi, I.H.; Saba, K.; Bukhari, M.H.

    2013-01-01

    Isolated hepatic tuberculosis without pulmonary or bowel involvement is a diagnostic challenge and can cause considerable morbidity. A young lady from Lahore presented with fever, pain in right hypochondria, nausea and weight loss. CT scan of abdomen showed multiple small hypodense non-enhancing lesions and a heterogeneous texture of liver. Biopsy confirmed the diagnosis of hepatic tuberculosis. It was concluded a case of isolated hepatic tuberculosis without evidence of other primary sites involvement. It is important to consider tuberculosis in the differential diagnosis when suspecting lymphoproliferative or metastatic diseases in a patient with vague symptoms and abnormal hepatic texture on CT. (author)

  7. A note on isolate domination

    Directory of Open Access Journals (Sweden)

    Ismail Sahul Hamid

    2016-04-01

    Full Text Available A set $S$ of vertices of a graph $G$ such that $\\left\\langle S\\right\\rangle$ has an isolated vertex is called an \\emph{isolate set} of $G$. The minimum and maximum cardinality of a maximal isolate set are called the \\emph{isolate number} $i_0(G$ and the \\emph{upper isolate number} $I_0(G$ respectively. An isolate set that is also a dominating set (an irredundant set is an $\\emph{isolate dominating set} \\ (\\emph{an isolate irredundant set}$. The \\emph{isolate domination number} $\\gamma_0(G$ and the \\emph{upper isolate domination number} $\\Gamma_0(G$ are respectively the minimum and maximum cardinality of a minimal isolate dominating set while the \\emph{isolate irredundance number} $ir_0(G$ and the \\emph{upper isolate irredundance number} $IR_0(G$ are the minimum and maximum cardinality of a maximal isolate irredundant set of $G$. The notion of isolate domination was introduced in \\cite{sb} and the remaining were introduced in \\cite{isrn}. This paper further extends a study of these parameters.   

  8. Emotion regulation during isolation

    Czech Academy of Sciences Publication Activity Database

    Poláčková Šolcová, Iva; Šolcová, Iva

    2012-01-01

    Roč. 47, Suppl. 1 (2012) ISSN 0020-7594. [International Congress of Psychology /30./. 22.07.2012-27.07.2012, Cape Town] R&D Projects: GA ČR(CZ) GAP407/11/2226 Institutional support: RVO:68081740 Keywords : emotion regulation * isolation * Mars500 Subject RIV: AN - Psychology

  9. Beyond insulation and isolation

    DEFF Research Database (Denmark)

    Højlund, Marie Koldkjær

    2016-01-01

    are insulation and isolation strategies to reduce measurable and perceptual noise levels. However, these strategies do not actively support the need to feel like an integral part of the shared hospital environment, which is a key element in creating healing environments, according to the paradigm of Evidence-Based...

  10. Fault isolation techniques

    Science.gov (United States)

    Dumas, A.

    1981-01-01

    Three major areas that are considered in the development of an overall maintenance scheme of computer equipment are described. The areas of concern related to fault isolation techniques are: the programmer (or user), company and its policies, and the manufacturer of the equipment.

  11. Proteoglycan isolation and analysis

    DEFF Research Database (Denmark)

    Woods, A; Couchman, J R

    2001-01-01

    Proteoglycans can be difficult molecules to isolate and analyze due to large mass, charge, and tendency to aggregate or form macromolecular complexes. This unit describes detailed methods for purification of matrix, cell surface, and cytoskeleton-linked proteoglycans. Methods for analysis...

  12. Isolated limb perfusion.

    Science.gov (United States)

    Gillespie, Rosalyn; Chantier, Nariane

    1994-12-08

    Growing concern over the rising incidence of malignant melanoma has brought about a need for information on this disorder and the treatment available. Isolated limb perfusion is a relatively new technique used in only a few hospitals. An increased knowledge base will lead to a better understanding of the nursing care required and to a more in-depth care plan.

  13. Broadband Faraday isolator.

    Science.gov (United States)

    Berent, Michał; Rangelov, Andon A; Vitanov, Nikolay V

    2013-01-01

    Driving on an analogy with the technique of composite pulses in quantum physics, we theoretically propose a broadband Faraday rotator and thus a broadband optical isolator, which is composed of sequences of ordinary Faraday rotators and achromatic quarter-wave plates rotated at the predetermined angles.

  14. Elective culture of bacteria used in bioleaching on pyrrhotite

    Institute of Scientific and Technical Information of China (English)

    邱冠周; 覃文庆; 蓝卓越; 黎维中

    2003-01-01

    Elective culture of bacteria on pyrrhotite was researched, and the selected bacteria were tested on bi-oleaching of marmatite and zinc sulfide ore. The results show that the microorganism cultured on pyrrhotite with va-rious S/Fe ratios is a mixed culture of thiobacillus ferrooxidans and thiobacillus thiooxidans, of which the integral ac-tivity and the oxidation capability of Fe2+ and S are enhanced. With the high Fe and low S content of pyrrhotite, the oxida-tion capacity of ferrous ion is improved; on the contrary, the oxidation capacity of sulfur is advanced. The bioleaching ca-pacity of bacteria cultured on marmatite is better than that of the bacteria cultivated by conventional methods.

  15. Application of bacterial leaching technology to deep solution-mining conditions for uranium extraction. Final report, September 1, 1978-September 30, 1981

    International Nuclear Information System (INIS)

    Brierley, J.A.; Brierley, C.L.; Torma, A.E.

    1982-03-01

    Microorganisms were evaluated for use in recovery of uranium under conditions of in-situ solution mining. The cultures tested were Thiobacillus ferrooxidans, the faculative-thermophilic TH3 strain, and two Sulfolobus species. Growth of the organisms occurred in the presence of 0.34 to 5.0 mM uranyl ion with higher concentrations being inhibitory. Uranium ore from the Anaconda Minerals Co. Jackpile mine was not readily leachable by microorganisms. To support bacterial activity the ore was supplemented with pyrite or ferrous iron. The ore possessed some toxic properties. T. ferrooxidans was able to assist in leaching of uranium from the ore at a hydrostatic pressure of 10.3 MPa

  16. Using microbiological leaching method to remove heavy metals from sludge

    Directory of Open Access Journals (Sweden)

    Zhuyu Gu

    2017-01-01

    Full Text Available Microbial leaching is one of the most effective methods to remove heavy metals from sludge. In the conducted researches, the sludge samples were processed with Thiobacillus ferrooxidans and Thiobacillus thiooxidans obtained via cultivation, extraction and purification processes. Heavy metals such as Pb, Cd, Cu and Ni were leached from sludge by Thiobacillus ferrooxidans and Thiobacillus thiooxidans within different substrate concentration and pH value conditions. It is defined that from the point of view of economy and efficiency the optimal concentration of FeSO4.7H2O and sulfur for bio-leaching process was 0.2 g. The leaching rates of heavy metals such as Pb, Cd, Cu and Ni of the same concentration were 74.72%, 81.54%, 70.46% and 77.35% respectively. However, no significant differences depending on the pH value among the leaching rates were defined, even for the pH value of 1.5. Along with the removal of heavy metals from sludge, the organic matter, N, P, K were also leached to some extent. The losing rate of phosphorus was the highest and reached 38.44%. However, the content of organic matter, N, P, K in the processed sludge were higher in comparison with level I of the National Soil Quality Standards of China. Ecological risk of heavy metals in sludge before and after leaching was assessed by Index of Geo-accumulation (Igeo and comprehensive potential risk (RI. The results of research defined that the content of heavy metals in sludge meets the level of low ecological risk after leaching and their contents is lower in comparison with the National Agricultural Sludge Standard of China. Sludge leached by biological methods is possible to use for treatment for increasing soil fertility.

  17. Waste pyritic coal as a raw material for energetic industry

    Energy Technology Data Exchange (ETDEWEB)

    Gasiorek, J. [Institute of Inorganic Chemistry, Poznan (Poland). Dept. of Research and Technology

    1997-11-01

    Results are presented of large laboratory studies on coal desulphurisation with foam flotation method improved by application of bioadsorption of Thiobacillus ferrooxidans bacteria to the modification of superficial properties of pyrite particulates from hydrophobic to hydrophillic ones. Results of coal desulfurization with and without bioadsorption have been compared. Bioadsorption improved pyritic sulfur removal by 30% (for coal from `Sierza mine`, coal size 0.3 to 0.102 mm, S pyritic content 1.69%) after 6-week adaptation of bacteria and 30 min of bioadsorption. Bacteria concentration in 5% water suspension of coal reached 22 {mu}g of biomass cm{sup -3}. 12 refs., 4 figs., 1 tab.

  18. Research within the coordinated progamme on bacterial leaching of uranium ores

    International Nuclear Information System (INIS)

    Marjanovic, D.

    1978-01-01

    Effect of magnetic field on the growth rate of Thiobacillus ferrooxidans bacteria was studied at intensities of 30, 100, 2400, and 4000 Oe. Low intensity magnetic field was found to stimulate the bacteria growth rate and the rate of ferrosulphate oxidation with optimum values at 30 to 300 Oe (maximum at 300 Oe). Magnetic field of high intensity (2400, 3200, 4000 Oe) inhibits the growth of bacteria and processes of bacterial oxidation. The possibility was also studied of using biocides for inhibiting bacterial processes in uranium-bearing waste dumps. The use of biocides resulted in a decrease of uranium-bearing waste dump autochthonous microflora density

  19. High voltage isolation transformer

    Science.gov (United States)

    Clatterbuck, C. H.; Ruitberg, A. P. (Inventor)

    1985-01-01

    A high voltage isolation transformer is provided with primary and secondary coils separated by discrete electrostatic shields from the surfaces of insulating spools on which the coils are wound. The electrostatic shields are formed by coatings of a compound with a low electrical conductivity which completely encase the coils and adhere to the surfaces of the insulating spools adjacent to the coils. Coatings of the compound also line axial bores of the spools, thereby forming electrostatic shields separating the spools from legs of a ferromagnetic core extending through the bores. The transformer is able to isolate a high constant potential applied to one of its coils, without the occurrence of sparking or corona, by coupling the coatings, lining the axial bores to the ferromagnetic core and by coupling one terminal of each coil to the respective coating encasing the coil.

  20. Psychopathology of social isolation

    OpenAIRE

    Baek, Sang-Bin

    2014-01-01

    The most important defining factor of being human is the use of symbolic language. Language or communication problem occurs during the growth, the child will have a higher risk of social isolation and then the survival will be threatened constantly. Today, adolescents and youths are familiar with computer and smart-phone devices, and communication with others by these devices is easy than face-to-face communication. As adolescents and youths live in the comfortable and familiar cyber-world ra...

  1. Mechanical beam isolator

    International Nuclear Information System (INIS)

    Post, R.F.; Vann, C.S.

    1996-10-01

    Back-reflections from a target, lenses, etc. can gain energy passing backwards through a laser just like the main beam gains energy passing forwards. Unless something blocks these back-reflections early in their path, they can seriously damage the laser. A Mechanical Beam Isolator is a device that blocks back-reflections early, relatively inexpensively, and without introducing aberrations to the laser beam

  2. Neglected isolated scaphoid dislocation

    Directory of Open Access Journals (Sweden)

    Jong-Ryoon Baek

    2016-01-01

    Full Text Available The authors present a case of isolated scaphoid dislocation in a 40-year-old male that was undiagnosed for 2 months. The patient was treated by open reduction, Kirschner wire fixation, interosseous ligament repair using a suture anchor and Blatt's dorsal capsulodesis. At 6 years followup, his radiographs of wrist showed a normal carpal alignment with a scapholunate gap of 3 mm and no evidence of avascular necrosis (AVN of the scaphoid.

  3. Miniature Optical Isolator, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — To address NASA's need for compact optical isolators, Physical Optics Corporation (POC) proposes to continue the development of a new Miniature Optical Isolator...

  4. Isolation and Cultivation of Anaerobes

    DEFF Research Database (Denmark)

    Aragao Börner, Rosa

    2016-01-01

    Anaerobic microorganisms play important roles in different biotechnological processes. Their complex metabolism and special cultivation requirements have led to less isolated representatives in comparison to their aerobic counterparts.In view of that, the isolation and cultivation of anaerobic...

  5. Diabetes in population isolates

    DEFF Research Database (Denmark)

    Grarup, Niels; Moltke, Ida; Albrechtsen, Anders

    2015-01-01

    Type 2 diabetes (T2D) is an increasing health problem worldwide with particularly high occurrence in specific subpopulations and ancestry groups. The high prevalence of T2D is caused both by changes in lifestyle and genetic predisposition. A large number of studies have sought to identify...... on glucose-stimulated plasma glucose, serum insulin levels, and T2D. The variant defines a specific subtype of non-autoimmune diabetes characterized by decreased post-prandial glucose uptake and muscular insulin resistance. These and other recent findings in population isolates illustrate the value...

  6. Journey from isolation

    Directory of Open Access Journals (Sweden)

    Wim A. Dreyer

    2011-04-01

    Full Text Available Since the Ottawa Consultation in 1982, the relationship between the Nederduitsch Hervormde Kerk van Afrika (NHKA and the World Alliance of Reformed Churches (WARC was nonexistent. In the NHKA it became progressively clear that it would be impossible to travel the road of faith alone. This article examined the factors which contributed to the growing isolation of the NHKA, especially nationalism, a particularistic ecclesiology and the rejection of Apartheid by international ecumenical bodies. It also reflected on efforts of the NHKA to return to the international ecumenical movement.

  7. Waste isolation: a bibliography

    International Nuclear Information System (INIS)

    McLaren, L.H.

    1982-12-01

    This bibliography contains information on waste isolation included in the Department of Energy's Energy Data Base from Janurary 1981 through November 1982. The abstracts are grouped by subject category as shown in the table of contents. Entries in the subject index also facilitate access by subject, e.g., Radioactive Waste Disposal/Salt Deposits. Within each category the arrangement is by report number for reports, followed by nonreports in reverse chronological order. These citations are to research reports, journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes, each preceded by a brief description, are provided: Corporate Author, Personal Author, Subject, Contract Number, and Report Number

  8. Yeast Isolation for Bioethanol Production

    Directory of Open Access Journals (Sweden)

    EKA RURIANI

    2012-09-01

    Full Text Available We have isolated 12 yeast isolates from five different rotten fruits by using a yeast glucose chloramphenicol agar (YGCA medium supplemented with tetracycline. From pre-screening assay, four isolates exhibited higher substrate (glucose-xylose consumption efficiency in the reaction tube fermentation compared to Saccharomyces cerevisiae dan Saccharomyces ellipsoids as the reference strains. Based on the fermentation process in gooseneck flasks, we observed that two isolates (K and SB showed high fermentation efficiency both in sole glucose and mixed glucose-xylose substrate. Moreover, isolates K and SB produced relatively identical level of ethanol concentration compared to the reference strains. Isolates H and MP could only produce high levels of ethanol in glucose fermentation, while only half of that amount of ethanol was detected in glucose-xylose fermentation. Isolate K and SB were identified as Pichia kudriavzeevii (100% based on large sub unit (LSU ribosomal DNA D1/D2 region.

  9. Isolated sulfite oxidase deficiency.

    Science.gov (United States)

    Rupar, C A; Gillett, J; Gordon, B A; Ramsay, D A; Johnson, J L; Garrett, R M; Rajagopalan, K V; Jung, J H; Bacheyie, G S; Sellers, A R

    1996-12-01

    Isolated sulfite oxidase (SO) deficiency is an autosomal recessively inherited inborn error of sulfur metabolism. In this report of a ninth patient the clinical history, laboratory results, neuropathological findings and a mutation in the sulfite oxidase gene are described. The data from this patient and previously published patients with isolated sulfite oxidase deficiency and molybdenum cofactor deficiency are summarized to characterize this rare disorder. The patient presented neonatally with intractable seizures and did not progress developmentally beyond the neonatal stage. Dislocated lenses were apparent at 2 months. There was increased urine excretion of sulfite and S-sulfocysteine and a decreased concentration of plasma cystine. A lactic acidemia was present for 6 months. Liver sulfite oxidase activity was not detectable but xanthine dehydrogenase activity was normal. The boy died of respiratory failure at 32 months. Neuropathological findings of cortical necrosis and extensive cavitating leukoencephalopathy were reminiscent of those seen in severe perinatal asphyxia suggesting an etiology of energy deficiency. A point mutation that resulted in a truncated protein missing the molybdenum-binding site has been identified.

  10. Schizosaccharomyces isolation method

    Directory of Open Access Journals (Sweden)

    Benito Santiago

    2014-01-01

    Full Text Available This study discusses the optimization of a selective and differential medium which would facilitate the isolation of Schizosaccharomyces (a genus with a low incidence compared to other microorganisms to select individuals from this genus for industrial purposes, especially in light of the recent recommendation of the use of yeasts from this genus in the wine industry by the International Organisation of Vine and Wine, or to detect the presence of such yeasts, for those many authors who consider them food spoilers. To this end, we studied various selective differential agents based on the main physiological characteristics of these species, such as their high resistances to high concentrations of sugar, sulfur dioxide, sorbic acid, benzoic acid, acetic acid or malo ethanolic fermentation. This selective medium is based on the genus resistance to the antibiotic actidione and its high resistance to inhibitory agents such as benzoic acid. Malic acid was used as a differential factor due to the ability of this genus to metabolise it to ethanol, which allows detecting of the degradation of this compound. Lastly, the medium was successfully used to isolate strains of Schizosaccharomyces pombe from honey and honeycombs.

  11. Isolated Cardiac Hydatid Cyst

    International Nuclear Information System (INIS)

    Shakil, U.; Rehman, A. U.; Shahid, R.

    2015-01-01

    Hydatid cyst disease is common in our part of the world. Cardiac hydatid cyst is its rare manifestation. We report this case of 48-year male having isolated cardiac hydatid cyst, incidentally found on computed tomography. This patient presented in medical OPD of Combined Military Hospital, Lahore with one month history of mild retrosternal discomfort. His general physical and systemic examinations as well as ECG were unremarkable. Chest X-ray showed an enlarged cardiac shadow with mildly irregular left heart border. Contrast enhanced CT scan of the chest showed a large well defined multiloculated non-enhancing cystic lesion with multiple daughter cysts involving wall of left ventricle and overlying pericardium. Serology for echinococcus confirmed the diagnosis of hydatid cyst. Patient was offered the surgical treatment but he opted for medical treatment only. Albendezol was prescribed. His follow-up echocardiography after one month showed no significant decrease in size of the cyst. (author)

  12. The Neuroendocrinology of Social Isolation

    Science.gov (United States)

    Cacioppo, John T.; Cacioppo, Stephanie; Capitanio, John P.; Cole, Steven W.

    2016-01-01

    Social isolation has been recognized as a major risk factor for morbidity and mortality in humans for more than a quarter of a century. Although the focus of research has been on objective social roles and health behavior, the brain is the key organ for forming, monitoring, maintaining, repairing, and replacing salutary connections with others. Accordingly, population-based longitudinal research indicates that perceived social isolation (loneliness) is a risk factor for morbidity and mortality independent of objective social isolation and health behavior. Human and animal investigations of neuroendocrine stress mechanisms that may be involved suggest that (a) chronic social isolation increases the activation of the hypothalamic pituitary adrenocortical axis, and (b) these effects are more dependent on the disruption of a social bond between a significant pair than objective isolation per se. The relational factors and neuroendocrine, neurobiological, and genetic mechanisms that may contribute to the association between perceived isolation and mortality are reviewed. PMID:25148851

  13. The neuroendocrinology of social isolation.

    Science.gov (United States)

    Cacioppo, John T; Cacioppo, Stephanie; Capitanio, John P; Cole, Steven W

    2015-01-03

    Social isolation has been recognized as a major risk factor for morbidity and mortality in humans for more than a quarter of a century. Although the focus of research has been on objective social roles and health behavior, the brain is the key organ for forming, monitoring, maintaining, repairing, and replacing salutary connections with others. Accordingly, population-based longitudinal research indicates that perceived social isolation (loneliness) is a risk factor for morbidity and mortality independent of objective social isolation and health behavior. Human and animal investigations of neuroendocrine stress mechanisms that may be involved suggest that (a) chronic social isolation increases the activation of the hypothalamic pituitary adrenocortical axis, and (b) these effects are more dependent on the disruption of a social bond between a significant pair than objective isolation per se. The relational factors and neuroendocrine, neurobiological, and genetic mechanisms that may contribute to the association between perceived isolation and mortality are reviewed.

  14. Miniature Optical Isolator, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — To address NASA's need for miniature optical isolators in atom interferometry applications, Physical Optics Corporation (POC) proposes to develop a miniature optical...

  15. Genome Analysis of the Biotechnologically Relevant Acidophilic Iron Oxidising Strain JA12 Indicates Phylogenetic and Metabolic Diversity within the Novel Genus "Ferrovum".

    Directory of Open Access Journals (Sweden)

    Sophie R Ullrich

    Full Text Available Members of the genus "Ferrovum" are ubiquitously distributed in acid mine drainage (AMD waters which are characterised by their high metal and sulfate loads. So far isolation and microbiological characterisation have only been successful for the designated type strain "Ferrovum myxofaciens" P3G. Thus, knowledge about physiological characteristics and the phylogeny of the genus "Ferrovum" is extremely scarce.In order to access the wider genetic pool of the genus "Ferrovum" we sequenced the genome of a "Ferrovum"-containing mixed culture and successfully assembled the almost complete genome sequence of the novel "Ferrovum" strain JA12.The genome-based phylogenetic analysis indicates that strain JA12 and the type strain represent two distinct "Ferrovum" species. "Ferrovum" strain JA12 is characterised by an unusually small genome in comparison to the type strain and other iron oxidising bacteria. The prediction of nutrient assimilation pathways suggests that "Ferrovum" strain JA12 maintains a chemolithoautotrophic lifestyle utilising carbon dioxide and bicarbonate, ammonium and urea, sulfate, phosphate and ferrous iron as carbon, nitrogen, sulfur, phosphorous and energy sources, respectively.The potential utilisation of urea by "Ferrovum" strain JA12 is moreover remarkable since it may furthermore represent a strategy among extreme acidophiles to cope with the acidic environment. Unlike other acidophilic chemolithoautotrophs "Ferrovum" strain JA12 exhibits a complete tricarboxylic acid cycle, a metabolic feature shared with the closer related neutrophilic iron oxidisers among the Betaproteobacteria including Sideroxydans lithotrophicus and Thiobacillus denitrificans. Furthermore, the absence of characteristic redox proteins involved in iron oxidation in the well-studied acidophiles Acidithiobacillus ferrooxidans (rusticyanin and Acidithiobacillus ferrivorans (iron oxidase indicates the existence of a modified pathway in "Ferrovum" strain JA12

  16. Canadian geologic isolation program

    International Nuclear Information System (INIS)

    Dyne, P.J.

    1976-01-01

    The Canadian geologic isolation program is directed at examining the potential of (1) salt deposits and (2) hard rock as repositories for radioactive wastes. It was felt essential from the inception that alternative host rocks be evaluated over a fairly large geographical area. The studies on salt deposits to date are based on existing geological information and have identified the areas that show some potential and merit further study. The factors considered include depth, thickness and purity of the deposit, overlying aquifers, and the potential for gas and oil exploration as well as potash recovery. The studies on hard rock are restricted to plutonic igneous rocks in the Ontario part of the Canadian Shield. Because geological information on their nature and extent is sparse, the study is limited to bodies that are well exposed and for which information is available.for which information is available. Field studies in the next two seasons are aimed at mapping the fault and joint patterns and defining the geologic controls on their development. In 1977 and 1978, two or three of the more favorable sites will be mapped in greater detail, and an exploratory drilling program will be established to determine the extent of fracturing at depth and the hydrology of these fractures. Conceptual designs of mined repositories in hard rock are also being made with the hope of identifying, at an early stage in this program, special problems in hard-rock repositories that may require development and study

  17. Isolated Amoebic Abscess of Spleen

    Directory of Open Access Journals (Sweden)

    Kaushik M

    2013-04-01

    Full Text Available Amoebic liver abscess is the most common extraintestinal manifestation of amoebiasis. Extrahepatic amoebic abscesses have occasionally been described in the lung, brain, and skin and presumably result from hematogenous spread. Isolated amoebic abscess of spleen has been reported scarcely in literature. We report here a case of isolated amoebic abscess of spleen.

  18. METHICILLIN RESISTANCE IN STAPHYLOCOCCAL ISOLATES ...

    African Journals Online (AJOL)

    The study assessed the importance of Staphylococcus aureus as a urinary pathogen and the incidence of multidrug resistant (MDR), methicillin-resistant Staphylococcus aureus (MRSA). A total of 86 staphylococcal isolates made up of 50 clinical isolates from urine samples submitted to the Medical Microbiology Laboratory ...

  19. Polyketides isolated from Penicillium herquei

    International Nuclear Information System (INIS)

    Marinho, Andrey Moacir do Rosario; Marinho, Patricia Santana Barbosa; Rodrigues Filho, Edson; Ferreira, Izabel Cristina Piloto

    2011-01-01

    In this work we are reporting the isolation of polyketides citreoserine (1), emodin (2), janthinone (3), dihydrocitrinone (4) and citrinin H-1 (5). The compounds were isolated by chromatographic procedures and identified by spectral methods of NMR 1D and 2D and MS. The compounds 1, 2 and 3 were tested against promastigotes of Leishmania brasiliensis. (author)

  20. Review of nuclear waste isolation

    International Nuclear Information System (INIS)

    Richard, B.H.

    1978-06-01

    On Jun 22 and 23, 1978, Rockwell Hanford Operations assembled a committee of their personnel, subcontractors, and representatives of other waste isolation programs for a review of nuclear waste isolation. Appendix A lists the participants and their affiliations; Appendix B indicates the agenda. The purpose of the review was to gather experts in the areas pertaining to isolation of nuclear waste to discuss three basic issues that must be addressed in isolation studies. These were: the paths of transport to the biosphere; the barriers needed for containment; and the isolation time necessary for each radioactive isotope. In that these issues are media dependent, the basalt medium was emphasized. Conclusions of the review are described

  1. Patients experience of source isolation

    DEFF Research Database (Denmark)

    Johansen, Kamilla; Pedersen, Didde; Kragbak, Nina

    2014-01-01

    , Nursing education in Århus, Hedeager 2, 8200 Aarhus N, Denmark. Background: Medical treatment and care of patients with infections may include source isolation of the patient, to avoid spreading of the infection. However, isolation is a potential physiological and psychological stress factor...... of the patients perspectives of being isolated to identify areas of potential interest for developing new caring strategies to minimize the negative side effects of isolation. Methods: Literature was systematically searched in CINAHL, Nursing Reference Center, Social Care Online, SveMed+, The Cochrane Library...... of Care: The patients felt abandoned and forgotten by the nurses, because of fewer visits and time limited communication. This led to emotions such as frustrations, insecurity and neglect. While isolated the patients felt it difficult to achieve contact and have an optimal relation with the nurses...

  2. Dynamic isolation technologies in negative pressure isolation wards

    CERN Document Server

    Xu, Zhonglin

    2017-01-01

    This book presents novel design principles and technologies for dynamic isolation based on experimental studies. These approaches have now become the local standard in Beijing and are currently being promoted for use nationwide. Further, the book provides details of measures and guidelines for the design process. Departing from the traditional understanding that isolation wards should be designed with high negative pressure, airtight doors and fresh air, it establishes the basis for designing biological clean rooms, including isolation wards, using a simple and convenient scientific approach. This book is intended for designers, engineers, researchers, hospital management staff and graduate students in heating ventilation air conditioning (HVAC), air cleaning technologies and related areas.

  3. Isolated Proofs of Knowledge and Isolated Zero Knowledge

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Nielsen, Jesper Buus; Wichs, Daniel

    2008-01-01

    . This is because the prover may just be forwarding messages between the environment and the verifier while the environment performs all the necessary computation. In this paper we consider an ℓ-isolated prover, which is restricted to exchanging at most ℓ bits of information with its environment. We introduce a new...... notion called ℓ-isolated proofs of knowledge (ℓ-IPoK). These protocols securely ensure that an ℓ-isolated prover knows the witness. To prevent the above-mentioned attack, an ℓ-IPoK protocol has to have communication complexity greater than ℓ. We show that for any relation in NP and any value ℓ...

  4. Waste Isolation Pilot Plant Overview

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, Douglas James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-03-27

    The mission of Waste Isolation Pilot Plant (WIPP) is to demonstrate the safe, environmentally sound, cost effective, permanent disposal of Transuranic (TRU) waste left from production of nuclear weapons.

  5. Seismic isolation in New Zealand

    International Nuclear Information System (INIS)

    Skinner, R.I.; Robinson, W.H.; McVerry, G.H.

    1989-01-01

    Bridges, buildings, and industrial equipment can be given increased protection from earthquake damage by limiting the earthquake attack through seismic isolation. A broad summary of the seismic responses of base-isolated structures is of considerable assistance for their preliminary design. Seismic isolation as already used in New Zealand consists of a flexible base or support combined with some form of energy-dissipating device, usually involving the hysteretic working of steel or lead. This paper presents examples of the New Zealand experience, where seismic isolation has been used for 42 bridges, 3 buildings, a tall chimney, and high-voltage capacitor banks. Additional seismic response factors, which may be important for nuclear power plants, are also discussed briefly

  6. WIPP: Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    1984-01-01

    The following aspects of the Waste Isolation Pilot Plant are discussed briefly: history and site selection; salt as a disposal medium; transporting waste materials; early key events; impacts on New Mexico; project organization; and site certification profile

  7. Isolation of rat adrenocortical mitochondria

    Energy Technology Data Exchange (ETDEWEB)

    Solinas, Paola [Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States); Department of Medicine, Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States); Fujioka, Hisashi [Electron Microscopy Facility, Department of Pharmacology, Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States); Tandler, Bernard [Department of Biological Sciences, School of Dental Medicine, Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States); Hoppel, Charles L., E-mail: charles.hoppel@case.edu [Department of Pharmacology, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States); Department of Medicine, Center for Mitochondrial Disease, School of Medicine, Case Western Reserve University, Cleveland, OH 44106 (United States)

    2012-10-12

    Highlights: Black-Right-Pointing-Pointer A method for isolation of adrenocortical mitochondria from the adrenal gland of rats is described. Black-Right-Pointing-Pointer The purified isolated mitochondria show excellent morphological integrity. Black-Right-Pointing-Pointer The properties of oxidative phosphorylation are excellent. Black-Right-Pointing-Pointer The method increases the opportunity of direct analysis of adrenal mitochondria from small animals. -- Abstract: This report describes a relatively simple and reliable method for isolating adrenocortical mitochondria from rats in good, reasonably pure yield. These organelles, which heretofore have been unobtainable in isolated form from small laboratory animals, are now readily accessible. A high degree of mitochondrial purity is shown by the electron micrographs, as well as the structural integrity of each mitochondrion. That these organelles have retained their functional integrity is shown by their high respiratory control ratios. In general, the biochemical performance of these adrenal cortical mitochondria closely mirrors that of typical hepatic or cardiac mitochondria.

  8. Isolation Effect in Immediate and Delayed Recall

    Science.gov (United States)

    Bellezza, Francis S.; Cheney, Terry L.

    1973-01-01

    If the hypothesis of selective rehearsal is used to account for the isolation effect, then the recall of isolated items will depend both on the serial position of the isolated item and on whether recall is immediate or delayed. (Author)

  9. Isolated Systolic Hypertension: A Health Concern?

    Science.gov (United States)

    Isolated systolic hypertension: A health concern? Is having a high top number (systolic) blood pressure, but a normal bottom number (diastolic) ... mm Hg, you have a common type of high blood pressure called isolated systolic hypertension. Isolated systolic hypertension can ...

  10. Waste isolation safety assessment program

    International Nuclear Information System (INIS)

    Brandstetter, A.; Harwell, M.A.

    1979-05-01

    Associated with commercial nuclear power production in the United States is the generation of potentially hazardous radioactive wastes. The Department of Energy (DOE), through the National Waste Terminal Storage (NWTS) Program, is seeking to develop nuclear waste isolation systems in geologic formations that will preclude contact with the biosphere of waste radionuclides in concentrations which are sufficient to cause deleterious impact on humans or their environments. Comprehensive analyses of specific isolation systems are needed to assess the expectations of meeting that objective. The Waste Isolation Safety Assessment Program (WISAP) has been established at the Pacific Northwest Laboratory (operated by Battelle Memorial Institute) for developing the capability of making those analyses. Among the analyses required for isolation system evaluation is the detailed assessment of the post-closure performance of nuclear waste repositories in geologic formations. This assessment is essential, since it is concerned with aspects of the nuclear power program which previously have not been addressed. Specifically, the nature of the isolation systems (e.g., involving breach scenarios and transport through the geosphere), and the time-scales necessary for isolation, dictate the development, demonstration and application of novel assessment capabilities. The assessment methodology needs to be thorough, flexible, objective, and scientifically defensible. Further, the data utilized must be accurate, documented, reproducible, and based on sound scientific principles

  11. Geomorphology of Minnesota - Isolated Landform Structures

    Data.gov (United States)

    Minnesota Department of Natural Resources — Geomorphology of Minnesota - Isolated Landform Structures are essentially cartographic arcs representing isolated glacial features that were mapped in conjunction...

  12. Sensitivity of seismically isolated structures

    International Nuclear Information System (INIS)

    Politopoulos, I.; Hoan, Khac Pham

    2009-01-01

    In this paper we study the sensitivity of seismically isolated structures to a small variability of the earthquake excitation and of some structural properties with respect to the probability of failure and floor spectra. In particular, the influence of the nonlinear behaviour of the isolated superstructure on the vulnerability and on the floor spectra is investigated by means of a series of Monte Carlo simulations of simple two degrees-of-freedom systems. Several types of passive and active isolation systems are examined and three different idealized nonlinear constitutive laws are considered for the superstructure. It is found that, in general, the probability of failure does not depend on the specific cyclic behaviour of the assumed constitutive law and general trends regarding the impact of different isolation devices on vulnerability are established. As for the floor spectra, the influence of moderate nonlinear behaviour of isolated Superstructures, with the exception of the case of a non-dissipative elastic nonlinear law is negligible, contrary to the case of conventional Structures. (authors)

  13. Sensitivity of seismically isolated structures

    Energy Technology Data Exchange (ETDEWEB)

    Politopoulos, I. [CEA Saclay, DEN DANS DM2S, 91 - Gif sur Yvette (France); Hoan, Khac Pham

    2009-07-15

    In this paper we study the sensitivity of seismically isolated structures to a small variability of the earthquake excitation and of some structural properties with respect to the probability of failure and floor spectra. In particular, the influence of the nonlinear behaviour of the isolated superstructure on the vulnerability and on the floor spectra is investigated by means of a series of Monte Carlo simulations of simple two degrees-of-freedom systems. Several types of passive and active isolation systems are examined and three different idealized nonlinear constitutive laws are considered for the superstructure. It is found that, in general, the probability of failure does not depend on the specific cyclic behaviour of the assumed constitutive law and general trends regarding the impact of different isolation devices on vulnerability are established. As for the floor spectra, the influence of moderate nonlinear behaviour of isolated Superstructures, with the exception of the case of a non-dissipative elastic nonlinear law is negligible, contrary to the case of conventional Structures. (authors)

  14. Isolated Echinococcosis of cervical region

    Directory of Open Access Journals (Sweden)

    Pratima Khare

    2014-01-01

    Full Text Available Echinococcosis, commonly called as hydatid disease, is a parasitic infestation caused by the larva of the genus Echinococcus in human. Isolated occurrence of Echinococcosis without any evidence of visceral disease is very rare. A thorough search of the literature revealed only 11 cases of isolated cervical Echinococcosis. We report here a very rare case of isolated hydatid cyst in a 45-year-old female patient, who presented with swelling in right cervical region about 5 cm below the angle of mandible with no evidence of the disease elsewhere in the body. The case was diagnosed on fine needle aspiration cytology. The diagnosis was further supported by histopathology. We propose that the treating physician should also consider the differential diagnosis of Echinococcosis in the presence of an asymptomatic soft tissue mass, especially when the patient lives in an endemic area.

  15. Sympathicotomy for isolated facial blushing

    DEFF Research Database (Denmark)

    Licht, Peter Bjørn; Pilegaard, Hans K; Ladegaard, Lars

    2012-01-01

    Background. Facial blushing is one of the most peculiar of human expressions. The pathophysiology is unclear, and the prevalence is unknown. Thoracoscopic sympathectomy may cure the symptom and is increasingly used in patients with isolated facial blushing. The evidence base for the optimal level...... of targeting the sympathetic chain is limited to retrospective case studies. We present a randomized clinical trial. Methods. 100 patients were randomized (web-based, single-blinded) to rib-oriented (R2 or R2-R3) sympathicotomy for isolated facial blushing at two university hospitals during a 6-year period...... between R2 and R2-R3 sympathicotomy for isolated facial blushing. Both were effective, and QOL increased significantly. Despite very frequent side effects, the vast majority of patients were satisfied. Surprisingly, many patients experienced mild recurrent symptoms within the first year; this should...

  16. VIBRATION ISOLATION SYSTEM PROBABILITY ANALYSIS

    Directory of Open Access Journals (Sweden)

    Smirnov Vladimir Alexandrovich

    2012-10-01

    Full Text Available The article deals with the probability analysis for a vibration isolation system of high-precision equipment, which is extremely sensitive to low-frequency oscillations even of submicron amplitude. The external sources of low-frequency vibrations may include the natural city background or internal low-frequency sources inside buildings (pedestrian activity, HVAC. Taking Gauss distribution into account, the author estimates the probability of the relative displacement of the isolated mass being still lower than the vibration criteria. This problem is being solved in the three dimensional space, evolved by the system parameters, including damping and natural frequency. According to this probability distribution, the chance of exceeding the vibration criteria for a vibration isolation system is evaluated. Optimal system parameters - damping and natural frequency - are being developed, thus the possibility of exceeding vibration criteria VC-E and VC-D is assumed to be less than 0.04.

  17. Isolation, characterization and identification of actinomycetes from ...

    African Journals Online (AJOL)

    A total of 62 isolates of actinomycetes were isolated from 7 soil samples collected from Agriculture Research Center Semongok, Sarawak. All 62 isolates exhibited a range of colony colours (dark grey, grey, dark brown, brownish, whitish and yellowish white). All the isolates were later purified and subjected to a few ...

  18. Isolated petrous apex ectopic craniopharyngioma

    Directory of Open Access Journals (Sweden)

    Julius July

    2015-12-01

    Full Text Available Primary ectopic craniopharyngioma is a rare entity. Isolated petrous apex bone location has not been reported previously. This study reports a case of 26-year-old male with right abducent nerve palsy. CT and MRI imaging reveal right petrous apex cystic lesion. No sellar or suprasellar region involvement was found. Endoscopic endonasal transphenoid approach has been successfully performed. Histopathology examination confirms the diagnosis of adamantinomatous craniopharyngioma. So far, it’s probably the first case report of primary ectopic craniopharyngioma isolated in the petrous apex. This case report supports the premise that primary ectopic craniopharyngioma is a multifactorial process that starts with an error from migrated embryological cells.

  19. Isolation contactor state control system

    Energy Technology Data Exchange (ETDEWEB)

    Bissontz, Jay E.

    2017-05-16

    A controller area network (CAN) installed on a hybrid electric vehicle provides one node with control of high voltage power distribution system isolation contactors and the capacity to energize a secondary electro-mechanical relay device. The output of the secondary relay provides a redundant and persistent backup signal to the output of the node. The secondary relay is relatively immune to CAN message traffic interruptions and, as a result, the high voltage isolation contactor(s) are less likely to transition open in the event that the intelligent output driver should fail.

  20. Seismic isolation of nuclear power plants using sliding isolation bearings

    Science.gov (United States)

    Kumar, Manish

    Nuclear power plants (NPP) are designed for earthquake shaking with very long return periods. Seismic isolation is a viable strategy to protect NPPs from extreme earthquake shaking because it filters a significant fraction of earthquake input energy. This study addresses the seismic isolation of NPPs using sliding bearings, with a focus on the single concave Friction Pendulum(TM) (FP) bearing. Friction at the sliding surface of an FP bearing changes continuously during an earthquake as a function of sliding velocity, axial pressure and temperature at the sliding surface. The temperature at the sliding surface, in turn, is a function of the histories of coefficient of friction, sliding velocity and axial pressure, and the travel path of the slider. A simple model to describe the complex interdependence of the coefficient of friction, axial pressure, sliding velocity and temperature at the sliding surface is proposed, and then verified and validated. Seismic hazard for a seismically isolated nuclear power plant is defined in the United States using a uniform hazard response spectrum (UHRS) at mean annual frequencies of exceedance (MAFE) of 10-4 and 10 -5. A key design parameter is the clearance to the hard stop (CHS), which is influenced substantially by the definition of the seismic hazard. Four alternate representations of seismic hazard are studied, which incorporate different variabilities and uncertainties. Response-history analyses performed on single FP-bearing isolation systems using ground motions consistent with the four representations at the two shaking levels indicate that the CHS is influenced primarily by whether the observed difference between the two horizontal components of ground motions in a given set is accounted for. The UHRS at the MAFE of 10-4 is increased by a design factor (≥ 1) for conventional (fixed base) nuclear structure to achieve a target annual frequency of unacceptable performance. Risk oriented calculations are performed for

  1. Active Fault Isolation in MIMO Systems

    DEFF Research Database (Denmark)

    Niemann, Hans Henrik; Poulsen, Niels Kjølstad

    2014-01-01

    isolation is based directly on the input/output s ignals applied for the fault detection. It is guaranteed that the fault group includes the fault that had occurred in the system. The second step is individual fault isolation in the fault group . Both types of isolation are obtained by applying dedicated......Active fault isolation of parametric faults in closed-loop MIMO system s are considered in this paper. The fault isolation consists of two steps. T he first step is group- wise fault isolation. Here, a group of faults is isolated from other pos sible faults in the system. The group-wise fault...

  2. Comparison of seismic isolation concepts for FBR

    International Nuclear Information System (INIS)

    Shiojiri, H.; Mazda, T.; Kasai, H.; Kanda, J.N.; Kubo, T.; Madokoro, M.; Shimomura, T.; Nojima, O.

    1989-01-01

    This paper seeks to verify the reliability and effectiveness of seismic isolation for FBR. Some results of the preliminary study of the program are described. Seismic isolation concepts and corresponding seismic isolation devices were selected. Three kinds of seismically-isolated FBR plant concepts were developed by applying promising seismic isolation concepts to the non-isolated FBR plant, and by developing plant component layout plans and building structural designs. Each plant was subjected to seismic response analysis and reduction in the amount of material of components and buildings were estimated for each seismic isolation concepts. Research and development items were evaluated

  3. Effect of light on Thiobacilli

    International Nuclear Information System (INIS)

    Le Roux, N.W.; Marshall, V.M.

    1977-01-01

    The aim was to study the effect of visible and ultra-violet light on some members of the genus Thiobacillus. This genus is one more example of an aerobic organism which undergoes what appears to be the widespread phenomenon of light inhibition. Light inhibition of thiobacilli has been observed before and these other observations are presented. In the present study the effect of both visible and U-V light on three species was considered, viz. T. thiooxidans, T. thioparus and T. ferrooxidans, the latter species being studied more thoroughly with respect to different intensities and wavelengths of light and the shielding effect of bacterial numbers and ferric iron. The photoreactivation of T. ferrooxidans cells after irradiation by U-V light was also examined. Using unfiltered, visible light, there was an inhibitory effect on all three of the thiobacilli irrespective of the source being used. When selected wavelengths were studied it was seen that the blue end of the visible spectrum was most inhibitory. A relationship between ferric iron concentration and protection from visible light was shown and the beneficial protective effect of particulate suspensions was demonstrated. The sensitivity of T. ferrooxidans and T. thioparus to U-V light and the protection afforded by ferric iron and cell numbers was assessed. Photoreactivation of U-V irradiated cells by exposure to visible light showed that this phenomenon occurred using wavelengths of visible light which, by themselves, were inhibitory. Some practical implication of these findings are offered. (orig.) [de

  4. Recent knowledge about the role of bacterial adhesion in coal preparation

    Directory of Open Access Journals (Sweden)

    Turèániová ¼udmila

    1998-09-01

    Full Text Available V nadväznosti na flotáciu pyritu v uhlí sú zhrnuté súèasné poznatky o vplyve fyzikálno-chemických vlastností buneènej steny baktérie Thiobacillus ferrooxidans na jej adhéziu na povrch rôznych minerálov a uhlia. Aplikovaním modelu mikrobiálnej adhézie (Škvarla, J. Chem. Soc. Faraday Trans., 89, 1993, p. 2913-2921 a využitím známych parametrov vstupujúcich do tohoto modelu bolo zistené, že k (reverzibilnej adhézii T. ferrooxidans dochádza spravidla v sekundárnom minime. Pre posúdenie možnosti využitia tohoto modelu na objasnenie selektívneho prichytenia T. ferrooxidans na pyrit je však potrebné doplni chýbajúce údaje vstupujúce do tohoto modelu.

  5. Physical isolation with virtual support

    DEFF Research Database (Denmark)

    Wearne, Susan M.; Teunissen, Pim W.; Dornan, Tim

    2015-01-01

    Purpose: Changing the current geographical maldistribution of the medical workforce is important for global health. Research regarding programs that train doctors for work with disadvantaged, rural populations is needed. This paper explores one approach of remote supervision of registrars in isol...

  6. Emotional isolation in BBC Forum

    International Nuclear Information System (INIS)

    Sienkiewicz, J; Chmiel, A

    2014-01-01

    We analyze emotionally annotated massive data from BBC Forum and examine properties of the isolation phenomenon of negative and positive users. Our results show the existence of a percolation threshold dependent on the average emotional value in the network of negatively charged nodes

  7. Sterols isolated from Tubifex tubifex.

    Science.gov (United States)

    Perez Gutierrez, Rosa Martha; Reyes, Ivan Cordova

    2006-11-01

    Four 3beta-hydroxysterols isolated from chloroform extract from Tubifex tubifex were shown to have the structures stigmast-23-en-3-ol, stigmast-7,14-dien-3-ol, 22-dehydrocholesterol, and 24 methylenecholesterol based on spectroscopic methods. Stigmasterol and beta-sitosterol were also investigated on the basis of mass spectral analyses and compared with known compounds.

  8. High-Voltage Isolation Transformer

    Science.gov (United States)

    Clatterbuck, C. H.; Ruitberg, A. P.

    1985-01-01

    Arcing and field-included surface erosion reduced by electrostatic shields around windings and ferromagnetic core of 80-kilovolt isolation transformer. Fabricated from high-resistivity polyurethane-based material brushed on critical surfaces, shields maintained at approximately half potential difference of windings.

  9. Isolated tricuspid valve infective endocarditis

    African Journals Online (AJOL)

    1990-07-07

    Jul 7, 1990 ... thromycin and cefamandole was isolated from multiple blood. Department of .... through the tricuspid orifice into the right atrium. ..... ('ma' 50) indicating adequate platelet function.) In the ... reponed here failed to prevent spontaneous haemorrhage ... this preparation is in shon supply and is very expensive.

  10. Isolating Lysosomes from Rat Liver.

    Science.gov (United States)

    Pryor, Paul R

    2016-04-01

    This protocol describes the generation of a fraction enriched in lysosomes from rat liver. The lysosomes are rapidly isolated using density-gradient centrifugation with gradient media that retain the osmolarity of the lysosomes such that they are functional and can be used in in vitro assays. © 2016 Cold Spring Harbor Laboratory Press.

  11. Optical isolation by Faraday rotator

    International Nuclear Information System (INIS)

    Kasai, Takeshi; Matsushima, Isao; Nemoto, Fusashi; Yano, Masaaki

    1984-01-01

    Three Faraday rotators designed as optical isolators in a high power glass laser system are described. The spatial fluctuation of applied magnetic field is less than 1% throughout the Faraday glass rod. The Faraday rotators transmit more than 80% of the forward-going laser light and reject more than 96% of the backward-going light. (author)

  12. SYMBIODINIUM ISOLATES FROM STONY CORAL: ISOLATION, GROWTH CHARACTERISTICS AND EFFECTS OF UV IRRADIATION

    Science.gov (United States)

    Symbiodinium spp. Isolates from Stony Coral: Isolation, Growth Characteristics and Effects of UV Irradiation (Abstract). J. Phycol. 37(3):42-43.Symbiodinium species were isolated from Montipora capitata, Acropora palmata and two field samples of Porites porites. Cultures ...

  13. Establishing the isolated Standard Model

    International Nuclear Information System (INIS)

    Wells, James D.; Zhang, Zhengkang; Zhao, Yue

    2017-02-01

    The goal of this article is to initiate a discussion on what it takes to claim ''there is no new physics at the weak scale,'' namely that the Standard Model (SM) is ''isolated.'' The lack of discovery of beyond the SM (BSM) physics suggests that this may be the case. But to truly establish this statement requires proving all ''connected'' BSM theories are false, which presents a significant challenge. We propose a general approach to quantitatively assess the current status and future prospects of establishing the isolated SM (ISM), which we give a reasonable definition of. We consider broad elements of BSM theories, and show many examples where current experimental results are not sufficient to verify the ISM. In some cases, there is a clear roadmap for the future experimental program, which we outline, while in other cases, further efforts - both theoretical and experimental - are needed in order to robustly claim the establishment of the ISM in the absence of new physics discoveries.

  14. Isolated urachal malakoplakia mimicking malignancy

    Directory of Open Access Journals (Sweden)

    Saisriharsha Pakalapati

    2017-01-01

    Full Text Available Malakoplakia is an unusual inflammatory disease with uncertain pathogenesis affecting any organ in the body, but predominantly genitourinary tract, with specific predilection to the bladder. We report a rare case of isolated malakoplakia of the urachus in a 29-year-old male patient who presented with lower urinary tract symptoms without any hematuria. Investigations revealed sterile pyuria with no bacterial growth in urine. Radiological investigations revealed a mass in the urachal region. The patient underwent cystoscopy with biopsy followed by pelvic lymph node dissection and partial cystectomy with excision of the urachal mass. Histopathological examination of the mass revealed malakoplakia. Postoperative course was uneventful. To the best of our knowledge, this is the first ever case report of isolated urachal malakoplakia without any concomitant malignancy or bladder involvement reported in our country and one of the very few reported worldwide.

  15. Isolated vasculitis of the CNS

    International Nuclear Information System (INIS)

    Block, F.; Reith, W.

    2000-01-01

    Vasculitis is a rare cause for disease of the CNS. The isolated vasculitis of the CNS is restricted to the CNS whereas other forms of vasculitis affect various organs including the CNS. Headache, encephalopathy, focal deficits and epileptic seizures are the major symptoms suggestive for vasculitis. One major criterion of the isolated vasculitis of the CNS is the lack of evidence for other vasculitis forms or for pathology of other organs. Angiography displays multifocal segmental stenosis of intracranial vessels. MRI demonstrates multiple lesions which in part show enhancement after gadolinium. A definite diagnosis can only be made on the grounds of biopsy from leptomeninges and parenchyma. Therapy consists of corticosteroids and cyclophosphamid. (orig.) [de

  16. Isolated adrenal paracoccidioidomycosis: Case report

    International Nuclear Information System (INIS)

    Uribe Castro, Jorge Ricardo; Quintana, Humberto; Puentes, Alix Sofia and others

    2011-01-01

    Even though paracoccidioidomycosis has a relatively high prevalence in Latin America in a systemic form, isolated cases, especially compromising the adrenal glands, are uncommon, with only two reported cases. In this article, we report the case of a 55 year-old male with clinical manifestations of adrenal insufficiency. The only imaging finding was the presence of bilateral adrenal masses. The biopsy showed Paracoccidioides brasiliensis infection.

  17. Transformerless dc-Isolated Converter

    Science.gov (United States)

    Rippel, Wally E.

    1987-01-01

    Efficient voltage converter employs capacitive instead of transformer coupling to provide dc isolation. Offers buck/boost operation, minimal filtering, and low parts count, with possible application in photovoltaic power inverters, power supplies and battery charges. In photovoltaic inverter circuit with transformerless converter, Q2, Q3, Q4, and Q5 form line-commutated inverter. Switching losses and stresses nil because switching performed when current is zero.

  18. Preparation and isolation of isobenzofuran

    Directory of Open Access Journals (Sweden)

    Morten K. Peters

    2017-12-01

    Full Text Available The synthesis, isolation and characterization of isobenzofuran are described in this publication. Isobenzofuran is of general interest in synthetic and physical organic chemistry because it is one of the most reactive dienes known. A number of synthetic pathways have been published which all suffer from disadvantages such as low yields and difficult purification. We present a synthetic pathway to prepare isobenzofuran in laboratory scale with high yields, from affordable, commercially available starting materials.

  19. Evolution of Isolated Neutron Stars

    OpenAIRE

    Popov, S. B.

    2001-01-01

    In this paper we briefly review our recent results on evolution and properties of isolated neutron stars (INSs) in the Galaxy. As the first step we discuss stochastic period evolution of INSs. We briefly discuss how an INS's spin period evolves under influence of interaction with turbulized interstellar medium. To investigate statistical properties of the INS population we calculate a {\\it census} of INSs in our Galaxy. Then we show that for exponential field decay the range of minimum value ...

  20. Tiamulin resistance in porcine Brachyspira pilosicoli isolates.

    Science.gov (United States)

    Pringle, M; Landén, A; Franklin, A

    2006-02-01

    There are few studies on antimicrobial susceptibility of Brachyspira pilosicoli, therefore this study was performed to investigate the situation among isolates from pigs. The tiamulin and tylosin susceptibility was determined by broth dilution for 93 and 86 porcine B. pilosicoli isolates, respectively. The isolates came from clinical samples taken in Swedish pig herds during the years 2002 and 2003. The tylosin minimal inhibitory concentration (MIC) was >16 microg/ml for 50% (n=43) of the isolates tested. A tiamulin MIC >2 microg/ml was obtained for 14% (n=13) of the isolates and these were also tested against doxycycline, salinomycin, valnemulin, lincomycin and aivlosin. For these isolates the susceptibility to salinomycin and doxycycline was high but the MICs for aivlosin varied. The relationship between the 13 tiamulin resistant isolates was analyzed by pulsed-field gel electrophoresis (PFGE). Among the 13 isolates 10 different PFGE patterns were identified.

  1. Input-output rearrangement of isolated converters

    DEFF Research Database (Denmark)

    Madsen, Mickey Pierre; Kovacevic, Milovan; Mønster, Jakob Døllner

    2015-01-01

    This paper presents a new way of rearranging the input and output of isolated converters. The new arrangement posses several advantages, as increased voltage range, higher power handling capabilities, reduced voltage stress and improved efficiency, for applications where galvanic isolation...

  2. Isolated malignant melanoma metastasis to the pancreas

    DEFF Research Database (Denmark)

    Larsen, Anne K; Krag, Christen; Geertsen, Poul

    2013-01-01

    SUMMARY: Malignant melanomas rarely develop isolated pancreatic metastases. We describe a unique patient who is still alive 22 years following an isolated pancreatic melanoma metastasis, and we review the sparse literature in the field....

  3. Isolated Horizon, Killing Horizon and Event Horizon

    OpenAIRE

    Date, G.

    2001-01-01

    We consider space-times which in addition to admitting an isolated horizon also admit Killing horizons with or without an event horizon. We show that an isolated horizon is a Killing horizon provided either (1) it admits a stationary neighbourhood or (2) it admits a neighbourhood with two independent, commuting Killing vectors. A Killing horizon is always an isolated horizon. For the case when an event horizon is definable, all conceivable relative locations of isolated horizon and event hori...

  4. Behavioural reproductive isolation and speciation in Drosophila

    Indian Academy of Sciences (India)

    In the genus Drosophila, the phenomenon of behavioural reproductive isolation, which is an important type of premating (prezygotic) reproductive isolating mechanisms, has been extensively studied and interesting data have been documented. In many cases incomplete sexual isolation has been observed and the pattern ...

  5. Isolation and morphological characterization of antibiotic producing ...

    African Journals Online (AJOL)

    Purpose: To isolate and characterize antibiotic producing actinomycetes from soil samples in Belgaum, Karnataka, India. Methods: Crowded plate technique was used for the isolation of actinomycetes in media such as soybean – casein digest medium and actinomycetes isolation agar. The morphological and cultural ...

  6. Isolation and characterization of copper tolerant bacterial isolates

    International Nuclear Information System (INIS)

    Farooq, S.; Shoeb, E.; Badar, U.; Akhtar, J.

    2008-01-01

    Twelve bacterial strains were isolated from metal contaminated sites close to the chemical factory, Purification and characterization of these strains was done. Maximum tolerable concentration (MTC) of all the isolated strains was determined against heavy metals cadmium chloride (CdCl/sub 2/), copper sulphate (CuSO/sub 4/), and nickel chloride (NiCI/sub 2/) and antibiotics kanamycin (Km), streptomycin (Sm), and chloramphenicol (Cm). Most promising strain was found to be GESSF012 which showed MTC of 4.5 mM and 1.6 mM against CdCI/sub 2/ in enriched and minimal media respectively; whereas MTC of 750 micro g/ml was against Sm. GESSF012 demonstrated the occurrence of multiple stress tolerance as this strain showed considerable tolerance against other heavy metals including CuSO/sub 4/, (3.0 mM in enriched media and 1.8 mM in minimal media) and NiCl/sub 2/, (2.0 mM in enriched media and 1.8 mM in minimal media) as well as other antibiotics Cm and Km (150 and 125 micro g/ml respectively). Plasmids were detected in most of the strains including GESSF012. (author)

  7. Fungi isolated in school buildings

    Directory of Open Access Journals (Sweden)

    Elżbieta Ejdys

    2013-12-01

    Full Text Available The aim of the study was to determine the species composition of fungi occurring on wall surfaces and in the air in school buildings. Fungi isolated from the air using the sedimentation method and from the walls using the surface swab technique constituted the study material. Types of finish materials on wall surfaces were identified and used in the analysis. Samples were collected in selected areas in two schools: classrooms, corridors, men's toilets and women's toilets, cloakrooms, sports changing rooms and shower. Examinations were conducted in May 2005 after the heating season was over. Fungi were incubated on Czapek-Dox medium at three parallel temperatures: 25, 37 and 40°C, for at least three weeks. A total of 379 isolates of fungi belonging to 32 genera of moulds, yeasts and yeast-like fungi were obtained from 321 samples in the school environment. The following genera were isolated most frequently: Aspergillus, Penicillium and Cladosporium. Of the 72 determined species, Cladosporium herbarum, Aspergillus fumigatus and Penicillium chrysogenum occurred most frequently in the school buildings. Wall surfaces were characterised by an increased prevalence of mycobiota in comparison with the air in the buildings, with a slightly greater species diversity. A certain species specificity for rough and smooth wall surfaces was demonstrated. Fungi of the genera Cladosporium and Emericella with large spores adhered better to smooth surfaces while those of the genus Aspergillus with smaller conidia adhered better to rough surfaces. The application of three incubation temperatures helped provide a fuller picture of the mycobiota in the school environment.

  8. Isolated penile torsion in newborns.

    Science.gov (United States)

    Eroglu, Egemen; Gundogdu, Gokhan

    2015-01-01

    We reported on the incidence of isolated penile torsion among our healthy children and our approach to this anomaly. Between 2011 and 2014, newborn babies with penile torsion were classified according to the angle of torsion. Surgical correction (penile degloving and reattachment for moderate cases and dorsal dartos flap technique in case of resistance) after 6 months was advised to the babies with rotations more than 45°. Among 1000 newborn babies, 200 isolated penile torsions were found, and among these, 43 had torsions more than 45°, and 4 of these had angles greater than 90°. The mean angle of the rotations was found 30.45° (median: 20°). In total, 8 children with 60° torsions were previously circumcised. Surgery was performed on 19 patients, with a mean patient age of 12 ± 2 months. Of these 19, 13 babies were corrected with degloving and reattachment. This technique was not enough on the remaining 6 patients; therefore, derotational dorsal dartos flap was added to correct the torsion. After a mean of 15.6 ± 9.8 months, residual penile rotation, less than 15°, was found only in 2 children. The incidence of isolated penile torsion is 20% in newborns. However, rotation more than 45° angles are seen in 4.3% of male babies. Correction is not necessary in mild degrees, and penile degloving with reattachment is enough in most cases. If the initial correction is insufficient, dorsal dartos flap rotation is easy and effective. Prior circumcision neither disturbs the operative procedure nor affects the outcomes.

  9. Basalt waste isolation project overview

    International Nuclear Information System (INIS)

    Dahlem, D.H.

    1987-01-01

    The proposed candidate site for a high-level nuclear waste repository is located beneath the Hanford Nuclear Reservation in southeastern Washington State. At this point, the Hanford Reservation has been selected as one of three preferred candidates in the draft environmental assessment. Project activities have concentrated on understanding the site location with respect to the 10CFR60, 40CFR191, and 10CFR960, identifying critical parameters for design of water package and repository seals, and identifying parameters for repository design. This paper describes the program to evaluate the site and to identify the natural processes that would effect isolation

  10. [Neuroanatomy of Isolated Body Lateropulsion].

    Science.gov (United States)

    Nakazato, Yoshihiko; Tamura, Naotoshi; Ikeda, Kei; Tanaka, Ai; Yamamoto, Toshimasa

    2016-03-01

    Axial body lateropulsion, a phenomenon where the body is pulled toward the side of the lesion, with tendency of falling down, is the well-known transient feature of lateral medullary syndrome. In some cases, axial body lateropulsion occurs without vestibular and cerebellar symptoms (isolated body lateropulsion:[iBL]). Patients with iBL have a lesion located in the spinocerebellar tract, descending lateral vestibulospinal tract, vestibulo-thalamic pathway, dentatorubrothalamic pathway, or thalamocortical fascicle. This review deals with the anatomic basis and clinical significance of iBL.

  11. Thermodynamic laws in isolated systems.

    Science.gov (United States)

    Hilbert, Stefan; Hänggi, Peter; Dunkel, Jörn

    2014-12-01

    The recent experimental realization of exotic matter states in isolated quantum systems and the ensuing controversy about the existence of negative absolute temperatures demand a careful analysis of the conceptual foundations underlying microcanonical thermostatistics. Here we provide a detailed comparison of the most commonly considered microcanonical entropy definitions, focusing specifically on whether they satisfy or violate the zeroth, first, and second laws of thermodynamics. Our analysis shows that, for a broad class of systems that includes all standard classical Hamiltonian systems, only the Gibbs volume entropy fulfills all three laws simultaneously. To avoid ambiguities, the discussion is restricted to exact results and analytically tractable examples.

  12. Variable stiffness and damping MR isolator

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, X Z; Wang, X Y; Li, W H; Kostidis, K [University of Wollongong, School of Mechanical, Materials and Mechatronic Engineering, NSW 2522 (Australia)], E-mail: weihuali@uow.edu.au

    2009-02-01

    This paper presents the development of a magnetorheological (MR) fluid-based variable stiffness and damping isolator for vibration suppressions. The MR fluid isolator used a sole MR control unit to achieve the variable stiffness and damping in stepless and relative large scope. A mathematical model of the isolator was derived, and a prototype of the MR fluid isolator was fabricated and its dynamic behavior was measured in vibration under various applied magnetic fields. The parameters of the model under various magnetic fields were identified and the dynamic performances of isolator were evaluated.

  13. Establishing the isolated Standard Model

    Energy Technology Data Exchange (ETDEWEB)

    Wells, James D.; Zhang, Zhengkang [Michigan Univ., Ann Arbor, MI (United States). Michigan Center for Theoretical Physics; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Zhao, Yue [Michigan Univ., Ann Arbor, MI (United States). Michigan Center for Theoretical Physics

    2017-02-15

    The goal of this article is to initiate a discussion on what it takes to claim ''there is no new physics at the weak scale,'' namely that the Standard Model (SM) is ''isolated.'' The lack of discovery of beyond the SM (BSM) physics suggests that this may be the case. But to truly establish this statement requires proving all ''connected'' BSM theories are false, which presents a significant challenge. We propose a general approach to quantitatively assess the current status and future prospects of establishing the isolated SM (ISM), which we give a reasonable definition of. We consider broad elements of BSM theories, and show many examples where current experimental results are not sufficient to verify the ISM. In some cases, there is a clear roadmap for the future experimental program, which we outline, while in other cases, further efforts - both theoretical and experimental - are needed in order to robustly claim the establishment of the ISM in the absence of new physics discoveries.

  14. Isolation of technogenic magnetic particles

    Energy Technology Data Exchange (ETDEWEB)

    Catinon, Mickaël, E-mail: mickael.catinon@gmail.com [Laboratoire LECA, UMR 5553, Equipe Pollution, Environnement, Ecotoxicologie et Ecoremédiation, Univ. J. Fourier, 38041 Grenoble (France); Ayrault, Sophie, E-mail: sophie.ayrault@lsce.ispl.fr [Laboratoire des Sciences du Climat et de l' Environnement, UMR 8212, CEA-CNRS-UVSQ/IPSL, 91198 Gif-sur-Yvette (France); Boudouma, Omar, E-mail: boudouma@ccr.jussieu.fr [Service du MEB, UFR928, Université Pierre et Marie Curie, 75252 Paris VI (France); Bordier, Louise, E-mail: Louise.Bordier@lsce.ipsl.fr [Laboratoire des Sciences du Climat et de l' Environnement, UMR 8212, CEA-CNRS-UVSQ/IPSL, 91198 Gif-sur-Yvette (France); Agnello, Gregory, E-mail: contact@evinrude.fr [Evinrude, Espace St Germain, 38200 Vienne (France); Reynaud, Stéphane, E-mail: stephane.reynaud@ujf-grenoble.fr [Laboratoire LECA, UMR 5553, Equipe Pollution, Environnement, Ecotoxicologie et Ecoremédiation, Univ. J. Fourier, 38041 Grenoble (France); Tissut, Michel, E-mail: michel.tissut@ujf-grenoble.fr [Laboratoire LECA, UMR 5553, Equipe Pollution, Environnement, Ecotoxicologie et Ecoremédiation, Univ. J. Fourier, 38041 Grenoble (France)

    2014-03-01

    Technogenic magnetic particles (TMPs) emitted by various industrial sources, such as smelting plants, end up after atmospheric transfer on the soil surface. In the present study, we characterised the origin and composition of such particles emitted by a large iron smelting plant and deposited on particular substrates, namely tombstones, which act as a very interesting and appropriate matrix when compared to soil, tree bark, lichens or attic dust. The isolation and subsequent description of TMPs require a critical step of separation between different components of the sample and the magnetic particles; here, we described an efficient protocol that fulfils such a requirement: it resorts to water suspension, sonication, repeated magnetic extraction, sedimentation, sieving and organic matter destruction at 550 °C in some instances. The isolated TMPs displayed a noticeable crystalline shape with variable compositions: a) pure iron oxides, b) iron + Cr, Ni or Zn, and c) a complex structure containing Ca, Si, Mg, and Mn. Using Scanning Electron Microscope Energy Dispersive X-ray (SEM–EDX), we obtained profiles of various and distinct magnetic particles, which allowed us to identify the source of the TMPs. - Highlights: • The developed method offers a low-cost approach of large-scale dry deposition. • Tombstones are excellent supports for sampling these atmospheric deposits. • Smelted elements crystallise after cooling, giving typical technogenic magnetic particles (TMPs). • Coupling microscopic and bulk analyses allows identifying TMP origin. • Magnetic TMPs issued from steel industry were separated by a new technique.

  15. Power inverter with optical isolation

    Science.gov (United States)

    Duncan, Paul G.; Schroeder, John Alan

    2005-12-06

    An optically isolated power electronic power conversion circuit that includes an input electrical power source, a heat pipe, a power electronic switch or plurality of interconnected power electronic switches, a mechanism for connecting the switch to the input power source, a mechanism for connecting comprising an interconnecting cable and/or bus bar or plurality of interconnecting cables and/or input bus bars, an optically isolated drive circuit connected to the switch, a heat sink assembly upon which the power electronic switch or switches is mounted, an output load, a mechanism for connecting the switch to the output load, the mechanism for connecting including an interconnecting cable and/or bus bar or plurality of interconnecting cables and/or output bus bars, at least one a fiber optic temperature sensor mounted on the heat sink assembly, at least one fiber optic current sensor mounted on the load interconnection cable and/or output bus bar, at least one fiber optic voltage sensor mounted on the load interconnection cable and/or output bus bar, at least one fiber optic current sensor mounted on the input power interconnection cable and/or input bus bar, and at least one fiber optic voltage sensor mounted on the input power interconnection cable and/or input bus bar.

  16. Assessing Social Isolation: Pilot Testing Different Methods.

    Science.gov (United States)

    Taylor, Harry Owen; Herbers, Stephanie; Talisman, Samuel; Morrow-Howell, Nancy

    2016-04-01

    Social isolation is a significant public health problem among many older adults; however, most of the empirical knowledge about isolation derives from community-based samples. There has been less attention given to isolation in senior housing communities. The objectives of this pilot study were to test two methods to identify socially isolated residents in low-income senior housing and compare findings about the extent of isolation from these two methods. The first method, self-report by residents, included 47 out of 135 residents who completed in-person interviews. To determine self-report isolation, residents completed the Lubben Social Network Scale 6 (LSNS-6). The second method involved a staff member who reported the extent of isolation on all 135 residents via an online survey. Results indicated that 26% of residents who were interviewed were deemed socially isolated by the LSNS-6. Staff members rated 12% of residents as having some or a lot of isolation. In comparing the two methods, staff members rated 2% of interviewed residents as having a lot of isolation. The combination of self-report and staff report could be more informative than just self-report alone, particularly when participation rates are low. However, researchers should be aware of the potential discrepancy between these two methods.

  17. Bacteriological lixiviation of low-grade uranium ores at low temperatures, by phiobacillus ferrooxidaus

    International Nuclear Information System (INIS)

    Lobato Filho, A.N.S.

    1976-12-01

    Laboratory experiments are described that, using selective and mutagenic agents, allowed the isolation of a strain of thiobacillus ferrooxidams capable of developing at 8 0 C, and keeping its oxidesing characteristics tests showed that the isoled sample is capable of solubilizing 95% of the uranium content in samples with U 3 O 8 content below 1000ppm [pt

  18. Oligotrophic bacteria isolated from clinical materials.

    OpenAIRE

    Tada, Y; Ihmori, M; Yamaguchi, J

    1995-01-01

    Oligotrophic bacteria (oligotrophs) are microorganisms that grow in extremely nutritionally deficient conditions in which the concentrations of organic substances are low. Many oligotrophic bacteria were isolated from clinical materials including urine, sputum, swabbings of the throat, vaginal discharges, and others. Seventy-seven strains of oligotrophic bacteria from 871 samples of clinical material were isolated. A relatively higher frequency of isolation of oligotrophic bacteria was shown ...

  19. Isolated trochlear nerve palsy with midbrain hemorrhage

    Directory of Open Access Journals (Sweden)

    Raghavendra S

    2010-01-01

    Full Text Available Midbrain hemorrhage causing isolated fourth nerve palsy is extremely rare. Idiopathic, traumatic and congenital abnormalities are the most common causes of fourth nerve palsy. We report acute isolated fourth nerve palsy in an 18-year-old lady due to a midbrain hemorrhage probably due to a midbrain cavernoma. The case highlights the need for neuroimaging in selected cases of isolated trochlear nerve palsy.

  20. Recent advances in micro-vibration isolation

    Science.gov (United States)

    Liu, Chunchuan; Jing, Xingjian; Daley, Steve; Li, Fengming

    2015-05-01

    Micro-vibration caused by disturbance sources onboard spacecraft can severely degrade the working environment of sensitive payloads. Some notable vibration control methods have been developed particularly for the suppression or isolation of micro-vibration over recent decades. Usually, passive isolation techniques are deployed in aerospace engineering. Active isolators, however, are often proposed to deal with the low frequency vibration that is common in spacecraft. Active/passive hybrid isolation has also been effectively used in some spacecraft structures for a number of years. In semi-active isolation systems, the inherent structural performance can be adjusted to deal with variation in the aerospace environment. This latter approach is potentially one of the most practical isolation techniques for micro-vibration isolation tasks. Some emerging advanced vibration isolation methods that exploit the benefits of nonlinearity have also been reported in the literature. This represents an interesting and highly promising approach for solving some challenging problems in the area. This paper serves as a state-of-the-art review of the vibration isolation theory and/or methods which were developed, mainly over the last decade, specifically for or potentially could be used for, micro-vibration control.

  1. Fault Isolation for Shipboard Decision Support

    DEFF Research Database (Denmark)

    Lajic, Zoran; Blanke, Mogens; Nielsen, Ulrik Dam

    2010-01-01

    Fault detection and fault isolation for in-service decision support systems for marine surface vehicles will be presented in this paper. The stochastic wave elevation and the associated ship responses are modeled in the frequency domain. The paper takes as an example fault isolation of a containe......Fault detection and fault isolation for in-service decision support systems for marine surface vehicles will be presented in this paper. The stochastic wave elevation and the associated ship responses are modeled in the frequency domain. The paper takes as an example fault isolation...... to the quality of decisions given to navigators....

  2. Genetics Home Reference: isolated growth hormone deficiency

    Science.gov (United States)

    ... can be inherited? More about Inheriting Genetic Conditions Diagnosis & Management Resources Genetic Testing (4 links) Genetic Testing Registry: Ateleiotic dwarfism Genetic Testing Registry: Autosomal dominant isolated somatotropin deficiency ...

  3. Loneliness and Social Isolation among Eldely People

    Directory of Open Access Journals (Sweden)

    Engin Püllüm

    2017-11-01

    Full Text Available Social isolation is defined as the process of people losing their contacts with other social resources or their willingness to participate. Social isolation is a grave and widespread problem among seniors in society causing many harmful health conditions. Social isolation may be prevented by defining risk factors in seniors and leading them to suitable resources. The elderly should be encouraged to share their experiences and continue to produce for as long as possible, so that they are prevented from feeling isolated from society and the continuity of their economic productivity is ensured.

  4. Mycoplasma contamination of Chlamydia pneumoniae isolates

    DEFF Research Database (Denmark)

    Huniche, BS; Jensen, Lise Torp; Birkelund, Svend

    1998-01-01

    media, immunoblotting, polymerase chain reaction and pulsed field gel electrophoresis. Two of the 6 ATCC isolates [ATCC VR1355 (TWAR strain 2043) and ATCC VR1356 (TWAR strain 2023)] were infected with Mycoplasma hominis and 1 isolate [ATCC VR2282 (TWAR strain TW183)] was contaminated with both...... Mycoplasma hominis and Mycoplasma orale, whereas 3 of the ATCC isolates [ATCC VR1310, ATCC VR1360 (TWAR strain CM-1) and ATCC 53592 (TWAR strain AR39)] were not contaminated. The Finnish C. pneumoniae isolates Kajaani 6 and Parola were found to be contaminated with M. hominis and M. orale, respectively...

  5. Permanent isolation surface barrier: Functional performance

    International Nuclear Information System (INIS)

    Wing, N.R.

    1993-10-01

    This document presents the functional performance parameters for permanent isolation surface barriers. Permanent isolation surface barriers have been proposed for use at the Hanford Site (and elsewhere) to isolate and dispose of certain types of waste in place. Much of the waste that would be disposed of using in-place isolation techniques is located in subsurface structures, such as solid waste burial grounds, tanks, vaults, and cribs. Unless protected in some way, the wastes could be transported to the accessible environment via transport pathways, such as water infiltration, biointrusion, wind and water erosion, human interference, and/or gaseous release

  6. Isolation and characterization of methanogenic bacteria from ...

    African Journals Online (AJOL)

    Isolation and characterization of methanogenic bacteria from brewery wastewater in Kenya. Sylvia Injete Murunga, Duncan Onyango Mbuge, Ayub Njoroge Gitau, Urbanus Ndungwa Mutwiwa, Ingrid Namae Wekesa ...

  7. Isolated systems with wind power. Main report

    DEFF Research Database (Denmark)

    Lundsager, P.; Bindner, Henrik W.; Clausen, Niels-Erik

    2001-01-01

    The overall objective of this research project is to study the development of methods and guidelines rather than "universal solutions" for the use of wind energy in isolated communities. The main specific objective of the project is to develop and present amore unified and generally applicable...... approach for assessing the technical and economical feasibility of isolated power supply systems with wind energy. As a part of the project the following tasks were carried out: Review of literature, fieldmeasurements in Egypt, development of an inventory of small isolated systems, overview of end...... for Isolated Systems with Wind Power, applicable for international organisations such as donoragencies and development banks....

  8. Update on clinically isolated syndrome.

    Science.gov (United States)

    Thouvenot, Éric

    2015-04-01

    Optic neuritis, myelitis and brainstem syndrome accompanied by a symptomatic MRI T2 or FLAIR hyperintensity and T1 hypointensity are highly suggestive of multiple sclerosis (MS) in young adults. They are called "clinically isolated syndrome" (CIS) and correspond to the typical first multiple sclerosis (MS) episode, especially when associated with other asymptomatic demyelinating lesions, without clinical, radiological and immunological sign of differential diagnosis. After a CIS, the delay of apparition of a relapse, which corresponds to the conversion to clinically definite MS (CDMS), varies from several months to more than 10 years (10-15% of cases, generally called benign RRMS). This delay is generally associated with the number and location of demyelinating lesions of the brain and spinal cord and the results of CSF analysis. Several studies comparing different MRI criteria for dissemination in space and dissemination in time of demyelinating lesions, two hallmarks of MS, provided enough substantial data to update diagnostic criteria for MS after a CIS. In the last revision of the McDonald's criteria in 2010, diagnostic criteria were simplified and now the diagnosis can be made by a single initial scan that proves the presence of active asymptomatic lesions (with gadolinium enhancement) and of unenhanced lesions. However, time to conversion remains highly unpredictable for a given patient and CIS can remain isolated, especially for idiopathic unilateral optic neuritis or myelitis. Univariate analyses of clinical, radiological, biological or electrophysiological characteristics of CIS patients in small series identified numerous risk factors of rapid conversion to MS. However, large series of CIS patients analyzing several characteristics of CIS patients and the influence of disease modifying therapies brought important information about the risk of CDMS or RRMS over up to 20 years of follow-up. They confirmed the importance of the initial MRI pattern of

  9. [Prenatal management of isolated IUGR].

    Science.gov (United States)

    Senat, M-V; Tsatsaris, V

    2013-12-01

    To evaluate the performance of different antenatal tools for the monitoring of fetuses with isolated intrauterine growth restriction (IUGR). To define the prenatal management of IUGR and indications for delivery before and after 32 weeks of gestation. PubMed, Embase and the Cochrane databases were searched using the keywords "IUGR", "fetal growth restriction", "cardiotocography", "amniotic fluid", "ultrasound assessment", "biophysical profile", "Doppler ultrasonography", "randomized trial", "meta-analysis". These terms were also combined together. Fetal monitoring of isolated IUGR should be based on the combined use of fetal heart rate (FHR) and ultrasound Doppler. The use of computerized FHR, with short-term variability (STV) measurement allows longitudinal monitoring and provides objective values upon which to decide very premature delivery (LE3). The use of umbilical Doppler is associated with a decrease in perinatal morbidity, especially in IUGR (LE1). It should be the first-line mean for the monitoring of SGA and IUGR fetuses (LE1). The additional use of cerebral Doppler is associated with a better predictive value for a poor perinatal outcome than the umbilical Doppler alone (LE3). Therefore, cerebral Doppler should be used in fetuses with IUGR, whether the umbilical Doppler is normal or not. As morbidity and mortality is increased in IUGR with pathological ductus venosus, the use of this Doppler should be considered in the monitoring of IUGR at before 32 weeks (professional consensus). Routine hospitalization is not mandatory for the monitoring of fetuses with IUGR/SGA. However, tertiary referral is advisable in cases of severe IUGR at between 26 to 32 weeks (professional consensus). The decision for delivery cannot be standardized and should be based on the combined analysis of gestational age, fetal heart rate analysis and Doppler study (professional consensus). Monitoring of fetuses with IUGR and decision for delivery should be based on the combined

  10. Single Cell Isolation and Analysis

    Directory of Open Access Journals (Sweden)

    Ping Hu

    2016-10-01

    Full Text Available Increasing evidence shows that the heterogeneity of individual cells within a genetically identical population can be critical to their peculiar function and fate. Conventional cell based assays mainly analysis the average responses from a population cells, while the difference within individual cells may often be masked. The cell size, RNA transcripts and protein expression level are quite different within individual cells and these variations are key point to answer the problems in cancer, neurobiology, stem cell biology, immunology and developmental biology. To better understand the cell-to-cell variations, the single cell analysis can provide much more detailed information which may be helpful for therapeutic decisions in an increasingly personalized medicine. In this review, we will focus on the recent development in single cell analysis, including methods used in single cell isolation, analysis and some application examples. The review provides the historical background to single cell analysis, discusses limitations, and current and future possibilities in this exciting field of research.

  11. Isolated polypeptide having arabinofuranosidase activity

    Science.gov (United States)

    Foreman, Pamela; Van Solingen, Pieter; Goedegebuur, Frits; Ward, Michael

    2010-02-23

    Described herein are novel gene sequences isolated from Trichoderma reesei. Two genes encoding proteins comprising a cellulose binding domain, one encoding an arabionfuranosidase and one encoding an acetylxylanesterase are described. The sequences, CIP1 and CIP2, contain a cellulose binding domain. These proteins are especially useful in the textile and detergent industry and in pulp and paper industry. TABLE-US-00001 cip1 cDNA sequence (SEQ ID NO: 1) GACTAGTTCA TAATACAGTA GTTGAGTTCA TAGCAACTTC 50 ACTCTCTAGC TGAACAAATT ATCTGCGCAA ACATGGTTCG CCGGACTGCT 100 CTGCTGGCCC TTGGGGCTCT CTCAACGCTC TCTATGGCCC AAATCTCAGA 150 CGACTTCGAG TCGGGCTGGG ATCAGACTAA ATGGCCCATT TCGGCACCAG 200 ACTGTAACCA GGGCGGCACC GTCAGCCTCG ACACCACAGT AGCCCACAGC 250 GGCAGCAACT CCATGAAGGT CGTTGGTGGC CCCAATGGCT ACTGTGGACA 300 CATCTTCTTC GGCACTACCC AGGTGCCAAC TGGGGATGTA TATGTCAGAG 350 CTTGGATTCG GCTTCAGACT GCTCTCGGCA GCAACCACGT CACATTCATC 400 ATCATGCCAG ACACCGCTCA GGGAGGGAAG CACCTCCGAA TTGGTGGCCA 450 AAGCCAAGTT CTCGACTACA ACCGCGAGTC CGACGATGCC ACTCTTCCGG 500 ACCTGTCTCC CAACGGCATT GCCTCCACCG TCACTCTGCC TACCGGCGCG 550 TTCCAGTGCT TCGAGTACCA CCTGGGCACT GACGGAACCA TCGAGACGTG 600 GCTCAACGGC AGCCTCATCC CGGGCATGAC CGTGGGCCCT GGCGTCGACA 650 ATCCAAACGA CGCTGGCTGG ACGAGGGCCA GCTATATTCC GGAGATCACC 700 GGTGTCAACT TTGGCTGGGA GGCCTACAGC GGAGACGTCA ACACCGTCTG 750 GTTCGACGAC ATCTCGATTG CGTCGACCCG CGTGGGATGC GGCCCCGGCA 800 GCCCCGGCGG TCCTGGAAGC TCGACGACTG GGCGTAGCAG CACCTCGGGC 850 CCGACGAGCA CTTCGAGGCC AAGCACCACC ATTCCGCCAC CGACTTCCAG 900 GACAACGACC GCCACGGGTC CGACTCAGAC ACACTATGGC CAGTGCGGAG 1000 GGATTGGTTA CAGCGGGCCT ACGGTCTGCG CGAGCGGCAC GACCTGCCAG 1050 GTCCTGAACC CATACTACTC CCAGTGCTTA TAAGGGGATG AGCATGGAGT 1100 GAAGTGAAGT GAAGTGGAGA GAGTTGAAGT GGCATTGCGC TCGGCTGGGT 1150 AGATAAAAGT CAGCAGCTAT GAATACTCTA TGTGATGCTC ATTGGCGTGT 1200 ACGTTTTAAA AAAAAAAAAA AAAAAAAAAA AAAAAAAAAA AAAAAAAAAA 1250 AAAAAAAAAA AAAAAAAAAG GGGGCGGCCG C 1271

  12. Stability of isolated Barchan dunes

    Science.gov (United States)

    Fourrière, Antoine; Charru, François

    2010-11-01

    When sand grains are entrained by an air flow over a non-erodible ground, or with limited sediment supply from the bed, they form isolated dunes showing a remarkable crescentic shape with horns pointing downstream. These dunes, known as Barchan dunes, are commonly observed in deserts, with height of a few meters and velocity of a few meters per year (Bagnold 1941). These dunes also exist under water, at a much smaller, centimetric size (Franklin & Charru 2010). Their striking stability properties are not well understood yet. Two phenomena are likely to be involved in this stability: (i) relaxation effects of the sand flux which increases from the dune foot up to the crest, related to grain inertia or deposition, and (ii) a small transverse sand flux due to slope effects and the divergence of the streamlines of the fluid flow. We reproduced aqueous Barchan dunes in a channel, and studied their geometrical and dynamic properties (in particular their shape, velocity, minimum size, and rate of erosion). Using coloured glass beads (see the figure), we were then able to measure the particle flux over the whole dune surface. We will discuss the stability of these dunes in the light of our measurements.

  13. Cooling system upon reactor isolation

    International Nuclear Information System (INIS)

    Yamamoto, Kohei; Oda, Shingo; Miura, Satoshi

    1992-01-01

    A water level indicator for detecting the upper limit value for a range of using a suppression pool and a thermometer for detecting the temperature of water at the cooling water inlet of an auxiliary device are disposed. When a detection signal is intaken and the water level in the suppression pool reach the upper limit value for the range of use, a secondary flow rate control value is opened and a primary flow rate control valve is closed. When the temperature of the water at the cooling water inlet of the auxiliary device reaches the upper limit value, the primary and the secondary flow rate control valves are opened. During a stand-by state, the first flow rate control valve is set open and the secondary flow rate control valve is set closed respectively. After reactor isolation, if a reactor water low level signal is received, an RCIC pump is actuated and cooling water is sent automatically under pressure from a condensate storage tank to the reactor and the auxiliary device requiring coolants by way of the primary flow rate control valve. Rated flow rate is ensured in the reactor and cooling water of an appropriate temperature can be supplied to the auxiliary device. (N.H.)

  14. Cooling device upon reactor isolation

    International Nuclear Information System (INIS)

    Otsu, Tatsuya

    1995-01-01

    A vacuum breaking valve is disposed to a sucking pipeline of vacuum pumps. A sucking port of the breaking valve is connected with an exhaustion side of a relief valve of a liquid nitrogen-filled tank by way of communication pipes. When a cooling device is operated upon reactor isolation and the vacuum pumps are operated, a three directional electromagnetic valve is operated, and nitrogen discharged out of the exhaustion port of the relief valve of the liquid nitrogen-filled tank is sent to a nitrogen releasing port on the suction side of the vacuum breaking valve by way of the communication pipes and released to atmosphere. When the pressure in the vacuum tank is excessively lowered in this state and the vacuum breaking valve is opened, nitrogen flows from the nitrogen discharge port into the vacuum tank through the breaking valve, and are sent to a pressure suppression chamber by the vacuum pumps. Since a great amount of nitrogen is sent to the pressure suppression chamber, and the inflow of the air is reduced, increase of oxygen concentration in the pressure suppression chamber can be suppressed. (I.N.)

  15. Distinguishing Isolated Photons from Jets

    CERN Document Server

    Pieri, Marco; Branson, James G

    2006-01-01

    We have developed isolation and shower-shape variables that are optimized for reducing the jet background for a high transverse-energy photon signal. To help understand the relative importance of each variable, we have computed the background rejection power as a function of signal efficiency for these variables as well as for some simple combinations of variables. We find that a combination of tracker plus ECAL information can give very significant background rejection power. By adding information from the HCAL, the rejection power can be improved. In addition we find that a very significant reduction in background can be achieved by adding photon shower shape information from the ECAL to the Neural Net inputs. About 1 in 200 jets contains a high E_T electromagnetic shower that is reconstructed by the CMS software and is therefore a potential background for photon detection. An additional jet rejection factor of 100 with 80% photon efficiency (or 400 with 50% efficiency) can be achieved by using the isolatio...

  16. Review of the ISOL Method

    CERN Document Server

    Lindroos, M

    2004-01-01

    The ISOL technique was invented in Copenhagen over 50 years ago and eventually migrated to CERN where a suitable proton drive beam was available at the Syncho-Cyclotron. The quick spread of the technique from CERN to many other laboratories has resulted in a large user community, which has assured the continued development of the method, physics in the front-line of fundamental research and the application of the method to many applied sciences. The technique is today established as one of the main techniques for on-line isotope production of high intensity and high quality beams. The thick targets used allows the production of unmatched high intensity radioactive beams. The fact that the ions are produced at rest makes it ideally suitable for low energy experiments and for post acceleration using well established accelerator techniques. The many different versions of the technique will be discussed and the many facilities spread all over the world will be reviewed. The major developments at the existing faci...

  17. Isolation colling device for reactor

    International Nuclear Information System (INIS)

    Ikehara, Morihiko; Arai, Shigeki.

    1982-01-01

    Purpose: To prevent undesired operation of an emergency core cooling system due to excess lowering of water level in a reactor. Constitution: In an emergency facility adapted to drive a turbine, upon reactor isolation, with the excess steams of the reactor to operate a pump and thereby inject cooling water to the reactor, a water level detector is provided and connected to a pump exhaust valve control circuit, a turbine inlet valve control circuit and a by-pass valve control circuit. Valve ON-OFF is automatically controlled depending on the water level to thereby render the level constant. A by-pass pipe is branched from a pump exhaust pipe and connected to a condensate storage tank. When the water level rises due to water injection, the injecting water is returned to circulate by way of the by-pass pipe to the condensate storage tank under the ON-OFF for each of the valves while the turbine being kept to drive. Then, if the water level is lowered, water injection is started again by the ON-OFF for each of the valves. (Ikeda, J.)

  18. Urine Exosome Isolation and Characterization.

    Science.gov (United States)

    Street, Jonathan M; Koritzinsky, Erik H; Glispie, Deonna M; Yuen, Peter S T

    2017-01-01

    Exosomes are nanometer-scale, membrane-enclosed vesicles that can potentially be used to detect nephrotoxicity, and reveal the subsequent response of the kidney. Epithelial cells of every nephron segment can contribute to the urinary exosome population, which is rich in potential biomarkers, including membrane proteins such as transporters and receptors, transcription factors, and microRNAs. These exosomal biomarkers may be up- or downregulated upon nephrotoxicant exposure. Exosome isolation is an area of ongoing research. Although faster and simpler methods have been developed, ultracentrifugation remains a mainstay for purification. A single ultracentrifugation step provides an enriched preparation suitable for biomarker discovery, and a second ultracentrifugation on a sucrose/D 2 O cushion provides the purest exosome preparation currently available and may be preferred for bioactivity assays. The concentration of exosomes can be determined using Nanosight Nanoparticle Tracking Analysis and their contents studied with a variety of approaches including western blots for proteins and RT-qPCR for microRNAs.

  19. Blackbody Radiation from Isolated Neptunes

    Science.gov (United States)

    Ginzburg, Sivan; Sari, Re'em; Loeb, Abraham

    2016-05-01

    Recent analyses of the orbits of some Kuiper belt objects hypothesize the presence of an undiscovered Neptune-size planet at a very large separation from the Sun. The energy budget of Neptunes on such distant orbits is dominated by the internal heat released by their cooling rather than solar irradiation (making them effectively “isolated”). The blackbody radiation that these planets emit as they cool may provide the means for their detection. Here, we use an analytical toy model to study the cooling and radiation of isolated Neptunes. This model can translate a detection (or a null detection) to a constraint on the size and composition of the hypothesized “Planet Nine.” Specifically, the thick gas atmosphere of Neptune-like planets serves as an insulating blanket that slows down their cooling. Therefore, a measurement of the blackbody temperature, {T}{{eff}}˜ 50 {{K}}, at which a Neptune emits, can be used to estimate the mass of its atmosphere, {M}{{atm}}. Explicitly, we find the relation {T}{{eff}}\\propto {M}{{atm}}1/12. Despite this weak relation, a measurement of the flux at the Wien tail can constrain the atmospheric mass, at least to within a factor of a few, and provide useful limits to possible formation scenarios of these planets. Finally, we constrain the size and composition of Planet Nine by combining our model with the null results of recent all-sky surveys.

  20. Effect of isolation techniques on the characteristics of pigeon pea (Cajanus cajan) protein isolates

    OpenAIRE

    Adenekan, Monilola K.; Fadimu, Gbemisola J.; Odunmbaku, Lukumon A.; Oke, Emmanuel K.

    2017-01-01

    Abstract In this study, the effect of different isolation techniques on the isolated proteins from pigeon pea was investigated. Water, methanol, ammonium sulfate, and acetone were used for the precipitation of proteins from pigeon pea. Proximate composition, and antinutritional and functional properties of the pigeon pea flour and the isolated proteins were measured. Data generated were statistically analyzed. The proximate composition of the water‐extracted protein isolate was moisture 8.30%...

  1. Assessment of effectiveness of geologic isolation systems

    International Nuclear Information System (INIS)

    Soldat, J.K.; Napier, B.A.; Strenge, D.L.; Schreckhise, R.G.; Zimmerman, M.G.

    1981-01-01

    The program for Assessment of Effectiveness of Geologic Isolation Systems (AEGIS) is managed through PNL's Water and Land Resources Department and is funded through the Battelle Office of Nuclear Waste Isolation (ONWI). The Ecological Sciences Department was involved in two subtasks under AEGIS: Dose Methodology Development and Reference Site Initial Analysis (RSIA) for a Salt Dome

  2. Isolation and characterization of extreme halophilic archaea

    Energy Technology Data Exchange (ETDEWEB)

    Franze, Madlen; Cherkouk, Andrea [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). HZDR Young Investigator Group

    2017-06-01

    Extreme halophilic archaea from the family Halobactereacea represent a dominant part of the microbial community present in saline soils as well as rock salts. By using a culture-dependent approach different Haloarchaea could be isolated and were phylogenetic analysed. Interestingly, isolates closely related to different Halobacterium spp. were found in both environments.

  3. ASPECTS OF THE ISOLATION AND CHARACTERIZATON OF ...

    African Journals Online (AJOL)

    A local isolate of Alternaria alternata isolated from soil under the decaying cassava peels heap was screened for the production of a-amylase and hydrolysis of starch. The maximal dextrinizing amylolytic activity of the partially purified enzyme was obtained at temperature of 600C and pH 7.0. Apart from glucose, sucrose and ...

  4. Virus isolation: Specimen type and probable transmission

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Virus isolation: Specimen type and probable transmission. Over 500 CHIK virus isolations were made. 4 from male Ae. Aegypti (?TOT). 6 from CSF (neurological involvement). 1 from a 4-day old child (transplacental transmission.

  5. Isolation and characterization of extreme halophilic archaea

    International Nuclear Information System (INIS)

    Franze, Madlen; Cherkouk, Andrea

    2017-01-01

    Extreme halophilic archaea from the family Halobactereacea represent a dominant part of the microbial community present in saline soils as well as rock salts. By using a culture-dependent approach different Haloarchaea could be isolated and were phylogenetic analysed. Interestingly, isolates closely related to different Halobacterium spp. were found in both environments.

  6. Isolation and characterization of cellulolytic Bacillus licheniformis ...

    African Journals Online (AJOL)

    Eight cellulose degrading bacteria were isolated from compost and were identified as Bacillus licheniformis by 16S rRNA sequencing. Among the eight isolates, Bacillus licheniformis B4, B7 and B8 showed the highest cellulase activity. B. licheniformis B4 and B8 showed the maximum cellulase activity during the stationary ...

  7. Isolated gallbladder rupture following blunt abdominal injury

    African Journals Online (AJOL)

    2015-05-26

    May 26, 2015 ... Kaohsiung Medical University, Kaohsiung, Taiwan. Abstract. Isolated traumatic gallbladder rupture subsequent to blunt abdominal injury is rare. Most literatures on the subjects consist of case reports. We reported a rare case of isolated gallbladder rupture and discussed the possible predisposing factors to ...

  8. Experiments on seismic isolation in Italy

    International Nuclear Information System (INIS)

    Bonacina, G.; Bettinali, F.; Martelli, A.; Olivieri, M.

    1992-01-01

    Static and dynamic tests have been performed in Italy on high damping steel-laminated elastomer bearings in various scales, rubber specimens and structures isolated by means of such bearings, in the framework of studies in progress to support seismic isolation development. Tests on rubber specimens and bearings have already provided important data (vertical and horizontal stiffness, damping, creep, temperature, aging and scale effects, etc.), necessary for the development and validation of numerical models, comparison with the test results of isolated structure mockups and actual buildings, and improvement of design guidelines. Dynamic experiments of structures concerned both full-scale and scaled isolated structure mock-ups and actual isolated buildings (one of those forming the SIP Administration Center at Ancona, an isolated house at Squillace, Calabria). Both snap-back tests and forced excitation experiments were performed, to rather large displacements. The latter were both sinusoidal and (on a 1/4 scale mock-up) seismic, with one- and multidirectional simultaneous excitations. Test results have already demonstrated the adequacy of seismic isolation and have provided data useful for the comparison with single bearing test results and validation of numerical models for the analysis of isolated structures. This paper reports the main features and results of tests performed or in progress. Further tests planned have been mentioned in the Status Report. Numerical analysis of measured data and guidelines development have been discussed in separate technical papers. (author)

  9. Antagonist potential of Trichoderma indigenous isolates for ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... the severity of insects and pathogens attacks especially .... After 30-days of incubation at 26°C, the isolation of Trichoderma ... Percentage inhibition (I) of colony growth of P. palmivora was ..... In fact, our success in isolating.

  10. K-Basin isolation barrier seal

    International Nuclear Information System (INIS)

    Ruff, E.S.

    1994-10-01

    This report documents various aspects of the design, analysis, procurement, and fabrication of the hydraulic seal on the isolation barriers to be installed in the 100-K Area spent nuclear fuel basin. The isolation barrier is used to keep water in the basin in the event of an earthquake

  11. Noncommunicating Isolated Enteric Duplication Cyst in the ...

    African Journals Online (AJOL)

    Noncommunicating isolated enteric duplications in the abdomen are an extremely rare variant of enteric duplications with their own blood supply. We report a case of a noncommunicating isolated ileal duplication in a 10-month-old boy. He was admitted because of severe abdominal distension and developed irritability ...

  12. Experimental Study of Vibration Isolation Characteristics of a Geometric Anti-Spring Isolator

    Directory of Open Access Journals (Sweden)

    Lixun Yan

    2017-07-01

    Full Text Available In order to realize low-frequency vibration isolation, a novel geometric anti-spring isolator consisting of several cantilever blade springs are developed in this paper. The optimal design parameters of the geometric anti-spring isolator for different nonlinear geometric parameters are theoretically obtained. The transmissibility characteristic of the geometric anti-spring isolator is investigated through mathematical simulation. A geometric anti-spring isolator with a nonlinear geometric parameter of 0.92 is designed and its vibration isolation performance and nonlinearity characteristic is experimentally studied. The experiment results show that the designed isolator has good low-frequency vibration isolation performance, of which the initial isolation frequency is less than 3.6 Hz when the load weight is 21 kg. The jump phenomena of the response of the isolator under linear frequency sweep excitation are observed, and this result demonstrates that the geometric anti-spring isolator has a complex nonlinearity characteristics with the increment of excitation amplitude. This research work provides a theoretical and experimental basis for the application of the nonlinear geometric anti-spring low-frequency passive vibration isolation technology in engineering practice.

  13. Study on three dimensional seismic isolation system

    International Nuclear Information System (INIS)

    Morishita, Masaki; Kitamura, Seiji

    2003-01-01

    Japan Nuclear Cycle Development Institute (JNC) and Japan Atomic Power Company (JAPC) launched joint research programs on structural design and three-dimensional seismic isolation technologies, as part of the supporting R and D activities for the feasibility studies on commercialized fast breeder reactor cycle systems. A research project by JAPC under the auspices of the Ministry of Economy, Trade, and Industry (METI) with technical support by JNC is included in this joint study. This report contains the results of the research on the three-dimensional seismic isolation technologies, and the results of this year's study are summarized in the following five aspects. (1) Study on Earthquake Condition for Developing 3-dimensional Base Isolation System. The case study S2 is one of the maximum ground motions, of which the records were investigated up to this time. But a few observed near the fault exceed the case study S2 in the long period domain, depending on the fault length and conditions. Generally it is appropriate that the response spectra ratio (vertical/horizontal) is 0.6. (2) Performance Requirement for 3-dimensional Base Isolation System and Devices. Although the integrity map of main equipment/piping dominate the design criteria for the 3-dimensional base isolation system, the combined integrity map is the same as those of FY 2000, which are under fv=1Hz and over hv=20%. (3) Developing Targets and Schedule for 3-dimensional Isolation Technology. The target items for 3-dimensional base isolation system were rearranged into a table, and developing items to be examined concerning the device were also adjusted. A development plan until FY 2009 was made from the viewpoint of realization and establishment of a design guideline on 3-dimensional base isolation system. (4) Study on 3-dimensional Entire Building Base Isolation System. Three ideas among six ideas that had been proposed in FY2001, i.e., '3-dimensional base isolation system incorporating hydraulic

  14. Isolation and characterization of phenol degrading yeast.

    Science.gov (United States)

    Patel, Riddhi; Rajkumar, Shalini

    2009-04-01

    A phenol degrading yeast isolate was identified and characterized from the soil sample collected from a landfill site, in Ahmedabad, India, by plating the soil dilutions on Sabouraud's Dextrose Agar. The microscopic studies and biochemical tests indicated the isolate to be Saccharomyces cerevisiae. The phenol degrading potential of the isolate was measured by inoculation of pure culture in the mineral medium containing various phenol concentrations ranging from 100 to 800 mg l(-1 )and monitoring phenol disappearance rate at regular intervals of time. Growth of the isolate in mineral medium with various phenol concentrations was monitored by measuring the turbidity (OD(600) nm). The results showed that the isolated yeast was tolerant to phenol up to 800 mg(-1). The phenol degradation ranged from 8.57 to 100% for the concentration of phenol from 800 mg l(-1 )to 200 mg l(-1), respectively. ((c) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim).

  15. Isolation of Pasteurella multocida from broiler chickens

    Directory of Open Access Journals (Sweden)

    Sri Poernomo

    1996-06-01

    Full Text Available Pasteurella multocida, the etiological agent of fowl cholera, was isolated from five, 32 days oldbroilerchickens in the late of 1992. The chickens were from a farm located in Bogor area, raised in cages and each flock consisted of 1,550 broilers . Therewere 230 birds, aging from 28-31 days old, died with clinical signs of lameness and difficulty in breathing. Serological test of the isolate revealed serotype Aof Carter classification . To prove its virulences, the isolate was then inoculated into 3 mice subcutaneously. The mice died less then 24 hours postinoculation and P. multocida can be reisolated . The sensitivity test to antibiotics and sulfa preparations showed that the isolate was sensitive to ampicillin, doxycyclin, erythromycin, gentamycin, sulfamethoxazol-trimethoprim and baytril, but resistance to tetracyclin, kanamycin and oxytetracyclin. This is the first report of P. multocida isolation in broiler chickens in Indonesia, and it is intended to add information on bacterial diseases in poultry in Indonesia.

  16. Effect of isolation techniques on the characteristics of pigeon pea (Cajanus cajan) protein isolates.

    Science.gov (United States)

    Adenekan, Monilola K; Fadimu, Gbemisola J; Odunmbaku, Lukumon A; Oke, Emmanuel K

    2018-01-01

    In this study, the effect of different isolation techniques on the isolated proteins from pigeon pea was investigated. Water, methanol, ammonium sulfate, and acetone were used for the precipitation of proteins from pigeon pea. Proximate composition, and antinutritional and functional properties of the pigeon pea flour and the isolated proteins were measured. Data generated were statistically analyzed. The proximate composition of the water-extracted protein isolate was moisture 8.30%, protein 91.83%, fat 0.25%, ash 0.05%, and crude fiber 0.05%. The methanol-extracted protein isolate composition was moisture 7.87%, protein 91.83%, fat 0.17%, and ash 0.13%, while crude fiber and carbohydrates were not detected. The composition of the ammonium sulfate-extracted protein isolate was moisture 7.73%, protein 91.73%, fat 0.36, ash 0.13%, and crude fiber 0.67%. The acetone-extracted protein isolate composition was moisture 8.03%, protein 91.50%, ash 0.67%, and fat 0.30%, but crude fiber and carbohydrates were not detected. The isolate precipitated with ammonium sulfate displayed the highest foaming capacity (37.63%) and foaming stability (55.75%). Isolates precipitated with methanol and acetone had the highest water absorption capacity (160%). Pigeon pea protein isolates extracted with methanol and ammonium sulfate had the highest oil absorption capacity of 145%. Protein isolates recovered through acetone and methanol had the highest emulsifying capacity of 2.23% and emulsifying stability of 91.47%, respectively. The proximate composition of the recovered protein isolates were of high purity. This shows the efficiency of the extraction techniques. The isolates had desirable solubility index. All the isolation techniques brought significant impact on the characteristics of the isolated pigeon pea protein.

  17. Isolement et identification des levures.

    Directory of Open Access Journals (Sweden)

    S. DOMERCQ

    1967-06-01

    Full Text Available La fermentation du moût de raisin est assurée par les levures qui se trouvent sur la pellicule du raisin, sur les rafles, et aussi, par celles qui envahissent le matériel de vendange et de vinification dès que la récolte est commencée. L'apparition deLa fermentation du moût de raisin est assurée par les levures qui se trouvent sur la pellicule du raisin, sur les rafles, et aussi, par celles qui envahissent le matériel de vendange et de vinification dès que la récolte est commencée. L'apparition des signes de la fermentation est spontanée. La fermentation est rapide dans la majorité des cas, si elle devient trop violente et que la température s'élève dangeureusement, il faut la « canaliser », la calmer. Des accidents peuvent se produire; des arrêts de fermentation laissant des sucres non fermentés pouvant être attaqués par d'autres microorganismes, des développements de levures formant des substances nuisibles à la qualité; par la suite, il s'agit d'obtenir la stabilité du vin, en particulier, éviter les refermentations des vins doux. L'étude de ces problèmes nécessite une étude préliminaire, celle des levures responsables de la fermentation alcoolique du jus de raisin, qui ne peut être faite que sur des cultures pures, isolées au préalable à l'aide de prélèvements soigneusement réalisés.s signes de la fermentation est spontanée. La fermentation est rapide dans la majorité des cas, si elle devient trop violente et que la température s'élève dangeureusement, il faut la « canaliser », la calmer. Des accidents peuvent se produire; des arrêts de fermentation laissant des sucres non fermentés pouvant être attaqués par d'autres microorganismes, des développements de levures formant des substances nuisibles à la qualité; par la suite, il s'agit d'obtenir la stabilité du vin, en particulier, éviter les refermentations des vins doux. L'étude de ces problèmes nécessite une étude pr

  18. Heap leaching for uranium

    International Nuclear Information System (INIS)

    1988-01-01

    Denison Mines Ltd. is using two bacterial leaching processes to combat the high cost of extracting uranium from low grade ore in thin reefs. Both processes use thiobacillus ferro-oxidans, a bacterium that employs the oxidation of ferrous iron and sulphur as its source of energy for growth. The first method is flood leaching, in which ore is subjected to successive flood, drain and rest cycles. The second, trickle leaching, uses sprinklers to douse the broken muck continuously with leaching solution. In areas where grades are too low to justify the expense of hauling the ore to the surface, the company is using this biological process underground to recover uranium. In 1987 Denison recovered 840 000 lb of uranium through bacterial heap leaching. It plans to have biological in-place leaching contribute 25% of the total uranium production by 1990. (fig.)

  19. Mass spectrographic analysis of selected chemical elements by microbial leaching of zircon

    International Nuclear Information System (INIS)

    Becker, S.; Dietze, H.J.; Bullmann, M.; Iske, U.

    1986-01-01

    Spark source mass spectrometry is a useful method for chemical element analysis of geological and biological samples. This sensitive technique (detection limit down to the ppb-range) is used to analyze leaching processes by means of several microorganisms. The problem of microbial leaching of chemical resistent materials was tested under laboratory conditions with regard to possible analytical and technical applications. Leaching of metals with chemolithotrophic and heterotrophic, organic acids producing microorganisms has been investigated with zircon from the Baltic Shield containing 0.7% rare earth elements and 1.67% hafnium. When zircon is leached with strains of thiobacillus ferrooxidans about 80% of the rare earth elements, Hf, Th and U can be recovered. (orig.) [de

  20. Microbial detoxification of waste rubber material by wood-rotting fungi.

    Science.gov (United States)

    Bredberg, Katarina; Andersson, B Erik; Landfors, Eva; Holst, Olle

    2002-07-01

    The extensive use of rubber products, mainly tires, and the difficulties to recycle those products, has resulted in world wide environmental problems. Microbial devulcanisation is a promising way to increase the recycling of rubber materials. One obstacle is that several microorganisms tested for devulcanisation are sensitive to rubber additives. A way to overcome this might be to detoxify the rubber material with fungi prior to the devulcanisation. In this study, 15 species of white-rot and brown-rot fungi have been screened with regard to their capacity to degrade an aromatic model compound in the presence of ground waste tire rubber. The most effective fungus, Resinicium bicolor, was used for detoxification of rubber material. Increase in growth of the desulfurising bacterium Thiobacillus ferrooxidans in presence of the rubber treated with Resinicium bicolor compared to untreated rubber demonstrated that detoxification with fungi is possible.

  1. Are Isolated Indigenous Populations Headed toward Extinction?

    Directory of Open Access Journals (Sweden)

    Robert S Walker

    Full Text Available At least 50 indigenous groups spread across lowland South America remain isolated and have only intermittent and mostly hostile interactions with the outside world. Except in emergency situations, the current policy of governments in Brazil, Colombia, and Peru towards isolated tribes is a "leave them alone" strategy, in which isolated groups are left uncontacted. However, these no-contact policies are based on the assumption that isolated populations are healthy and capable of persisting in the face of mounting external threats, and that they can maintain population viability in the long-term. Here, we test this assumption by tracking the sizes and movements of cleared horticultural areas made by 8 isolated groups over the last 10-14 years. We used deforestation data derived from remote sensing Landsat satellite sensors to identify clearings, and those were then validated and assessed with high-resolution imagery. We found only a single example of a relatively large and growing population (c. 50 cleared ha and 400 people, whereas all of the other 7 groups exhibited much smaller villages and gardens with no sizable growth through time. These results indicated that the smaller groups are critically endangered, and it prompts an urgent re-thinking of policies toward isolated populations, including plans for well-organized contacts that may help save lives and rescue isolated indigenous populations from imminent extinction.

  2. Are Isolated Indigenous Populations Headed toward Extinction?

    Science.gov (United States)

    Walker, Robert S; Kesler, Dylan C; Hill, Kim R

    2016-01-01

    At least 50 indigenous groups spread across lowland South America remain isolated and have only intermittent and mostly hostile interactions with the outside world. Except in emergency situations, the current policy of governments in Brazil, Colombia, and Peru towards isolated tribes is a "leave them alone" strategy, in which isolated groups are left uncontacted. However, these no-contact policies are based on the assumption that isolated populations are healthy and capable of persisting in the face of mounting external threats, and that they can maintain population viability in the long-term. Here, we test this assumption by tracking the sizes and movements of cleared horticultural areas made by 8 isolated groups over the last 10-14 years. We used deforestation data derived from remote sensing Landsat satellite sensors to identify clearings, and those were then validated and assessed with high-resolution imagery. We found only a single example of a relatively large and growing population (c. 50 cleared ha and 400 people), whereas all of the other 7 groups exhibited much smaller villages and gardens with no sizable growth through time. These results indicated that the smaller groups are critically endangered, and it prompts an urgent re-thinking of policies toward isolated populations, including plans for well-organized contacts that may help save lives and rescue isolated indigenous populations from imminent extinction.

  3. Isolated microalbuminuria indicates a poor medical prognosis.

    Science.gov (United States)

    Scheven, Lieneke; Van der Velde, Marije; Lambers Heerspink, Hiddo J; De Jong, Paul E; Gansevoort, Ron T

    2013-07-01

    Microalbuminuria is often regarded as a sign of end-organ damage due to diabetes and/or hypertension, and as such to be associated with an increased risk for cardiovascular events. It has been questioned whether isolated microalbuminuria, that is microalbuminuria in the absence of a cardiovascular disease (CVD) history, hypertension and diabetes has clinical relevance. Included were 8356 subjects who participated in the first four screening rounds of the PREVEND study, a prospective, community-based, observational cohort study. Isolated microalbuminuria was defined as microalbuminuria (30-300 mg/24 h), in the absence of a CVD history, hypertension (blood pressuredefinition of isolated microalbuminuria, in which 2250 person-years of follow-up were available. In subjects with isolated microalbuminuria, the incidence rates of cardiovascular events and mortality, hypertension and diabetes were 15.3, 28.9 and 8.9 per 1000 person-year follow-up, respectively. Subjects with isolated microalbuminuria had an increased risk for cardiovascular events and mortality [crude HR 2.23 (1.63-3.07); Phypertension [OR 1.95 (1.47-2.59); Phypertension and/or diabetes. This increased risk remained significant after adjustment for age and gender. The relative risk held by isolated microalbuminuria was similar to the relative risk held by microalbuminuria in subjects that did have a CVD history, hypertension and/or diabetes. Isolated microalbuminuria indicates a poor prognosis and warrants medical attention.

  4. Different Babesia canis isolates, different diseases.

    Science.gov (United States)

    Schetters, T P; Moubri, K; Précigout, E; Kleuskens, J; Scholtes, N C; Gorenflot, A

    1997-11-01

    Using surface immunofluorescence isolate-specific antigens were detected on the membrane of erythrocytes infected with Babesia parasites. In addition, the strains reacted differently with Plasmagel in that the European isolate (B.c. canis) could be purified on Plasmagel effectively, whereas infected erythrocytes of the South-African isolate (B.c. rossi) could not. Experimental infection of dogs with Babesia canis isolates from geographically different areas revealed different pathology. The European isolate obtained from France exhibited transient parasitaemia, usually below 1%, associated with low PCV values and congestion of internal organs. Clinical disease was correlated with an effect on the coagulation system, and not with peripheral parasitaemia. Infection of dogs with South-African-derived isolate induced high parasitaemia usually much higher than 1%, which required chemotherapeutic treatment. In these animals clinical disease was correlated with peripheral parasitaemia and not with parameters of the coagulation system. The results show that the etiology of disease caused by these isolates of B.c. canis and B.c. rossi is different. This might have implications for the development of vaccines against these infections.

  5. Preventing social isolation in older people.

    Science.gov (United States)

    Cotterell, Natalie; Buffel, Tine; Phillipson, Christopher

    2018-07-01

    The extent of social isolation amongst older people has emerged as a major concern for health and social policy. Although the social and health outcomes of social isolation are well documented, evidence regarding the prevention of isolation in later life remains scarce. This article addresses this by presenting the findings from a literature review focusing on the identification, assessment, prevention, and intervention strategies relevant to social isolation in older age. The paper first addresses the issues of identification and assessment, using an ecological framework to identify the risk factors for social isolation at four levels: individual, relationship, community, and societal. It then reviews different types of interventions to reduce or prevent social isolation in later life, including one-to-one, group, service provision, technology-based, neighbourhood, and structural interventions. The paper discusses both the opportunities and the constraints associated with these different approaches. The discussion highlights future directions for research, emphasising the need for a cultural change from 'cure' to 'prevention' of social isolation across the life-course, and the importance of acknowledging greater diversity within the ageing population. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. EMPLACEMENT DRIFT ISOLATION DOOR CONTROL SYSTEM

    International Nuclear Information System (INIS)

    N.T. Raczka

    1998-01-01

    The purpose of this analysis is to review and refine key design concepts related to the control system presently under consideration for remotely operating the emplacement drift isolation doors at the potential subsurface nuclear waste repository at Yucca Mountain. This analysis will discuss the key design concepts of the control system that may be utilized for remotely monitoring, opening, and closing the emplacement drift isolation doors. The scope and primary objectives of this analysis are to: (1) Discuss the purpose and function of the isolation doors (Presented in Section 7.1). (2) Review the construction of the isolation door and other physical characteristics of the doors that the control system will interface with (Presented in Section 7.2). (3) Discuss monitoring and controlling the operation of the isolation doors with a digital control system (either a Programmable Logic Controller (PLC) system or a Distributed Control System (DCS)) (Presented in Section 7.3). (4) Discuss how all isolation doors can be monitored and controlled from a subsurface central control center (Presented in Section 7.4). This analysis will focus on the development of input/output (I/O) counts including the types of I/O, redundancy and fault tolerance considerations, and processor requirements for the isolation door control system. Attention will be placed on operability, maintainability, and reliability issues for the system operating in the subsurface environment with exposure to high temperatures and radiation

  7. Cryopreservation of Mycobacterium bovis isolates

    Directory of Open Access Journals (Sweden)

    Cássia Yumi Ikuta

    2016-11-01

    Full Text Available Research, development of new biotechnological methods, diagnostic tests, confirmation of results, and reinvestigations are possible because of the availability of well-preserved living organisms maintained without any changes. Cryopreservation is a simpler, more reliable and long-term stable method for culture maintenance. Storage temperature and composition of the suspending vehicle are factors that affect the viability of mycobacterial strains. Three vehicles and three storage temperatures were evaluated to define a suitable cryoprotective medium for the preservation of Mycobacterium bovis strains. Colonies of sixteen M. bovis isolates were used to prepare the suspensions, which were then added to three vehicles: sterile 0.85% saline solution (SS, Middlebrook 7H9 broth (7H9, and Middlebrook 7H9 broth with sodium pyruvate (7H9p replacing glycerol. Aliquots of these suspensions were frozen by three different methods, directly in the -20°C freezer, directly in the -80°C freezer, and at -196°C by immersion in liquid nitrogen (LN. The frozen aliquots were thawed at room temperature after 45, 90 and 120 days. Mycobacterial viability was assessed by counting the living cells on plates of Stonebrink medium before and after the freezing procedure. Storage at -20°C exhibited a lower recovery of M. bovis compared to storage at -80°C (Dunn’s test, p=0.0018 and LN (Dunn’s test, p=0.0352. There was no statistically significant difference between storage at -80°C and in LN (Dunn’s test, p=0.1403, yet -80°C showed better results than LN. All three suspending vehicles showed no statistically significant difference in terms of viability (Friedman’s test, p=0.7765. Given the low loss proportion of 5% during storage at -20°C and the high cost equipment required for storage at -80°C and LN, we recommend storage at -20°C or -80°C, when this is available, for preservation of M. bovis field strains.

  8. Genetic differences between avian and human isolates of Candida dubliniensis.

    LENUS (Irish Health Repository)

    McManus, Brenda A

    2009-09-01

    When Candida dubliniensis isolates obtained from seabird excrement and from humans in Ireland were compared by using multilocus sequence typing, 13 of 14 avian isolates were genetically distinct from human isolates. The remaining avian isolate was indistinguishable from a human isolate, suggesting that transmission may occur between humans and birds.

  9. Effect of Trichoderma isolates on tomato seedling growth response ...

    African Journals Online (AJOL)

    Trichoderma species are commonly used as biological control agents against phytopathogenic fungi and some isolates are able to improve plant growth. In this study, the effects of three Trichoderma isolates including Trichoderma harzianum isolate T969, T. harzianum isolate T447 and Trichoderma sp. isolate T in tomato ...

  10. Microbial ecology of Rum Jungle, III. Leaching behaviour of sulphidic waste material under controlled conditions

    International Nuclear Information System (INIS)

    Babij, T.; Goodman, A.; Khalid, A.M.; Ralph, B.J.

    1981-12-01

    The discharge, into river systems, of acid and heavy metals generated by leaching of sulphidic waste materials at the abandoned opencut uranium mine at Rum Jungle, Northern Territory, is causing continuing pollution of the surrounding environment. The maximum effects of acid and microorganisms on samples from the overburden dump material, under defined and controlled environmental conditions, were assessed using reactor systems. These samples came from the overburden dump resulting from the mining of White's orebody. Similarly, the stability of tailings material under conditions of flooding and increasing acidity was determined. At ph 2.5, metals in White's dump material were solubilised by acid attack only, whereas at pH 3.5, bacterial activity (principally that of Thiobacillus ferrooxidans) generated acidity and contributed significantly to metal release. Under microaerophilic conditions Thiobacillus ferrooxidans continued to effect metal release from the ore, but did not produce further acidity. If White's overburden is returned to the acidic, flooded opencuts, complete solubilisation of the material will occur. The exclusion of oxygen from the dump will not necessarily stop bacterially catalysed leaching processes. Under highly aerated and agitated flooded conditions the tailings material was not active, except for copper release of about 2 g kg -1 ore at pH 4.0. The only deleterious element released by increasing acidity was copper, which was 100 per cent solubilised at pH 2.5. Uranium was always lss than 3 μg kg -1 ore, and lead was detected only at pH 2.5. Indigenous leaching bacteria did not develop

  11. [Isolation of C. pyloridis from children].

    Science.gov (United States)

    Spirina, T S; Bokser, G V; Safonova, T B; Taranenko, L A; Levitskaia, S V

    1989-01-01

    The authors analyze the findings of gastroduodenal biopsies in 25 children aged 6 to 15 years suffering from mucosal inflammations and functional abnormalities of the upper portions of the digestive tract. Chocolate agar with various bases, one of which has been suggested by the authors, has been used for the isolation of C. pyloridis. Five cultures have been isolated. Microscopic examinations and biochemical identification of the isolates have lead the authors to a conclusion that campylobacter infections of the upper digestive tract may be diagnosed with certainty only after a comprehensive bacteriologic examination.

  12. Fault Detection and Isolation for Spacecraft

    DEFF Research Database (Denmark)

    Jensen, Hans-Christian Becker; Wisniewski, Rafal

    2002-01-01

    This article realizes nonlinear Fault Detection and Isolation for actuators, given there is no measurement of the states in the actuators. The Fault Detection and Isolation of the actuators is instead based on angular velocity measurement of the spacecraft and knowledge about the dynamics...... of the satellite. The algorithms presented in this paper are based on a geometric approach to achieve nonlinear Fault Detection and Isolation. The proposed algorithms are tested in a simulation study and the pros and cons of the algorithms are discussed....

  13. Improved containment isolation for CANDU plants

    Energy Technology Data Exchange (ETDEWEB)

    Stretch, A H [Atomic Energy of Canada Ltd., Mississauga, ON (Canada)

    1996-12-31

    The publication of Regulatory Policy Statement R- 7 in February 1991 by the Atomic Energy Control Board imposes new requirement for the isolation of fluid piping penetrating the containment boundary. The Appendix of R-7 describes the detailed requirements for metal extensions of the containment envelope, including the code classification qf the pressure retaining portions and isolation requirements for fluid piping and tubing.The application of these new requirements to the existing CANDU 6 design resulted in a number of design changes, including the addition of manual and automatic isolation valves, changes in code classification, and leakage monitoring considerations. (author). 3 refs., 3 figs.

  14. Isolators Including Main Spring Linear Guide Systems

    Science.gov (United States)

    Goold, Ryan (Inventor); Buchele, Paul (Inventor); Hindle, Timothy (Inventor); Ruebsamen, Dale Thomas (Inventor)

    2017-01-01

    Embodiments of isolators, such as three parameter isolators, including a main spring linear guide system are provided. In one embodiment, the isolator includes first and second opposing end portions, a main spring mechanically coupled between the first and second end portions, and a linear guide system extending from the first end portion, across the main spring, and toward the second end portion. The linear guide system expands and contracts in conjunction with deflection of the main spring along the working axis, while restricting displacement and rotation of the main spring along first and second axes orthogonal to the working axis.

  15. STREPTOMYCETE Producing Antibiotics Isolated From Egyptian Soil

    International Nuclear Information System (INIS)

    SALAMA, S.M; MAHMOUD, S.M; ELKABBANY, H.M.

    2010-01-01

    An investigation was concerned the distribution of Streptomyces species in some types of Egyptian soils. Thirty nine actinomycetes isolates were obtained from 7 types of Egyptian soils; 8 isolates exhibited antimicrobial activities against all tested organisms and three of them were identified as Streptomyces griseoluteus (YM23), Streptomyces aurantiogriseus (S15) and Streptomyces nogalator (H12). RAPD-PCR showed correlation between 8 isolates in 3 clades. The active metabolite was extracted with ethyl acetate and concentrated in vacuum and the crude fraction was purified using thin layer and column chromatography

  16. Earthquake response observation of isolated buildings

    International Nuclear Information System (INIS)

    Harada, O.; Kawai, N.; Ishii, T.; Sawada, Y.; Shiojiri, H.; Mazda, T.

    1989-01-01

    Base isolation system is expected to be a technology for a rational design of FBR plant. In order to apply this system to important structures, accumulation of verification data is necessary. From this point of view, the vibration test and the earthquake response observation of the actual isolated building using laminated rubber bearings and elasto-plastic steel dampers were conducted for the purpose of investigating its dynamic behavior and of proving the reliability of the base isolation system. Since September in 1986, more than thirty earthquakes have been observed. This paper presents the results of the earthquake response observation

  17. Isolated jejunal perforation following blunt abdominal trauma

    Directory of Open Access Journals (Sweden)

    Ahmet Pergel

    2012-09-01

    Full Text Available Isolated perforation of the jejunum, following blunt abdominaltrauma, is extremely rare. These injuries aredifficult to diagnose because initial clinical signs are frequentlynonspecific and a delay in treatment increasesmortality and morbidity of the patients. Conventional radiogramsare often inadequate for diagnosing this subsetof trauma. For an accurate and timely diagnosis, thepossibility of bowel perforation and the need for repeatedexaminations should be kept in mind. Herein, we presenta 28-year-old man with isolated jejunal perforation followingblunt abdominal trauma.Key words: Blunt abdominal trauma, isolated jejunal perforation,early diagnosis

  18. The heterogeneity of socially isolated older adults: a social isolation typology.

    Science.gov (United States)

    Machielse, Anja

    2015-01-01

    Recent statistics show a growing number of older adults who are living alone and are socially isolated. It is against this background that, in recent years, many interventions have been developed to address social isolation among the elderly. Evaluative studies show that most interventions are hardly effective, though. An important reason for this is the heterogeneity of the socially isolated. This article offers insight into this heterogeneity by presenting a typology with different profiles of socially isolated older adults and the intervention implications of this typology. The typology is derived from an extensive qualitative study on socially isolated elderly individuals in the Netherlands. The typology imposes some degree of order to a diversity of circumstances, ambitions, and possibilities of the socially isolated elderly, thereby deepening the understanding of the heterogeneity of this population. The definition of social isolation used in this study starts from a societal angle of incidence, namely the current policy context of Western European welfare states, in which governments emphasize the importance of independence and self-reliance of their citizens. Developed from that perspective, the typology provides a theoretical basis for applying interventions aimed at increasing self-reliance of social isolated elderly. This perspective on social isolation also has consequences for the way in which the effectiveness of interventions to alleviate social isolation is assessed.

  19. Optimization of yeast (Saccharomyces cerevisiae) RNA isolation ...

    African Journals Online (AJOL)

    Yomi

    2012-01-16

    Jan 16, 2012 ... isolation method for real-time quantitative PCR and microarray ... disease genes to experimental evolution and systems biology (Landry et al., .... scanning, and preliminary analyses with GeneChip Operating. Software 1.4 ...

  20. Antigenic typing Polish isolates of canine parvovirus

    Energy Technology Data Exchange (ETDEWEB)

    Mizak, B. [National Veterinary Research Institute, Pulawy (Poland); Plucienniczak, A. [Polish Academy ofd Sciences. Microbiology and Virology Center, Lodz (Poland)

    1995-12-31

    Polish strains of canine parvovirus isolated between 1982 and 1993 were examined to determine the extent to which the virus has evolved antigenically and genetically over eleven years. Two CPV isolates obtained in Warsaw in 1982 and Pulawy in 1993, were examined using monoclonal antibody typing, restriction analysis and sequencing VP-2 protein gene. Five other isolates from Warsaw and Pulawy were tested with the panel of monoclonal antibodies specific to CPV-2, CPV-2a and common for canine parvovirus, feline panleukopenia virus and milk enteritis virus. Results of the studies demonstrated that all isolates tested represented CPV-2a antigenic type. Rapid antigenic strain replacement recorded by Parrish and Senda in the U.S.A and Japan was not confirmed in Poland. (author). 30 refs, 2 tabs.

  1. ISOLATION AND IDENTIFICATION OF FUNGI RESPONSIBLE FOR ...

    African Journals Online (AJOL)

    User

    technique. The diseased plant leaves were taken to the laboratory for culture, isolation, and identification ... The tree is native to Asia particularly eastern India, Burma, and the Andaman ..... in Southeastern Nigeria and Biological. Control with ...

  2. Isolation and molecular characterisation of Mycobacterium bovis ...

    African Journals Online (AJOL)

    : Three hundred and six milk samples collected from 102 infected cows in different Tunisian regions were analysed. M. bovis isolates were further characterized by spoligotyping and variable number tandem repeat typing. Results: A total of ...

  3. A case of familial isolated hemihyperplasia

    Directory of Open Access Journals (Sweden)

    Bacino Carlos A

    2004-02-01

    Full Text Available Abstract Background Hemihyperplasia (hemihypertrophy is defined as asymmetric body overgrowth of one or more body parts. Hemihyperplasia can be isolated or be part of well-defined syndromes such as in the case of Beckwith-Wiedemann syndrome (BWS. Isolated hemihyperplasia is usually sporadic, but a number of familial occurrences have been described. Case presentation We describe a Tunisian family in which three maternal cousins and their maternal grandfather present with isolated hemihyperplasia. Conclusions The etiology of isolated hemihyperplasia is unknown although in BWS, genomic imprinting has been shown to play a role in the asymmetric overgrowth. Given the similarity between these two conditions, it is possible that both may share a common pathogenesis. We also discuss the possible genetic mechanisms leading to the production of hemihyperplasia in this family.

  4. Isolation and characterization of biogenic calcium carbonate ...

    Indian Academy of Sciences (India)

    Biogenic calcium carbonate/phosphate were isolated and characterized from oral bacteria (CPOB). The crystalline nature ... XRD analysis revealed the cubic phase of ... subjected to identify upto genus level according to Bergey's. Manual of ...

  5. Isolate resistance of Blastocystis hominis to metronidazole.

    Science.gov (United States)

    Haresh, K; Suresh, K; Khairul Anus, A; Saminathan, S

    1999-04-01

    Isolates of Blastocystis hominis from infected immigrant workers from Indonesia, Bangladesh and infected individuals from Singapore and Malaysia were assessed for growth pattern and degree of resistance to different concentrations of metronidazole. Viability of the cells was assessed using eosin-brillian cresyl blue which stained viable cells green and nonviable cells red. The Bangladeshi and Singaporean isolates were nonviable even at the lowest concentration of 0.01 mg/ml, whereas 40% of the initial inoculum of parasites from the Indonesian isolate at day one were still viable in cultures with 1.0 mg/ml metronidazole. The study shows that isolates of B. hominis of different geographical origin have different levels of resistance to metronidazole. The search for more effective drugs to eliminate th parasite appears inevitable, especially since surviving parasites from metronidazole cultures show greater ability to multiply in subcultures than controls.

  6. Occurrence, isolation and DNA identification of Streptococcus ...

    African Journals Online (AJOL)

    ajl yemi

    2011-11-28

    Nov 28, 2011 ... Streptococcus thermophilus involved in Algerian ... among reference, and wild strains of S. thermophilus and for their differentiation from Enterococcus spp. ..... Isolation and characterization of Lactobacillus delbrueckii ssp.

  7. Connecting Vietnam's isolated communities to improve healthcare ...

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

    2018-01-29

    Jan 29, 2018 ... Connecting Vietnam's isolated communities to improve healthcare ... of pregnancy and new motherhood improved their interactions with health workers. ... Return to main page: Overcoming eHealth challenges with social and ...

  8. AEROBIC BACTERIAL ISOLATES FROM INFECTED WOUNDS

    African Journals Online (AJOL)

    boaz

    most frequently reported as the cause of delay wound healing (6-9, 3). ... All isolates were resistant to Ampicillin, Amoxicillin- clavulanate and .... Ulcer bed infection. Report of a case of enlarging venous leg ulcer colonized by ... Ann. Burns Fire.

  9. Isolated torsion of fallopian tube. Radiological findings

    International Nuclear Information System (INIS)

    Tomas Fanjul, L.; Aldea Martinez, J.; Fernandez Matia, G.; Rodrigo Verguizas, J.; Fernandez Alvarez, G.; Galindo Vicente, M.C.

    1993-01-01

    Isolated tubal torsion is a very uncommon disorder that is rarely diagnosed preoperatively. We present a case and review the literature, which only provides ultrasonographic findings in 5 cases reported to date. 11 refs

  10. Genetics Home Reference: isolated sulfite oxidase deficiency

    Science.gov (United States)

    ... and Management Resources (1 link) GeneReview: Isolated Sulfite Oxidase Deficiency General Information from MedlinePlus (5 links) Diagnostic Tests Drug Therapy Genetic Counseling Palliative Care Surgery and ...

  11. Antigenic typing Polish isolates of canine parvovirus

    International Nuclear Information System (INIS)

    Mizak, B.; Plucienniczak, A.

    1995-01-01

    Polish strains of canine parvovirus isolated between 1982 and 1993 were examined to determine the extent to which the virus has evolved antigenically and genetically over eleven years. Two CPV isolates obtained in Warsaw in 1982 and Pulawy in 1993, were examined using monoclonal antibody typing, restriction analysis and sequencing VP-2 protein gene. Five other isolates from Warsaw and Pulawy were tested with the panel of monoclonal antibodies specific to CPV-2, CPV-2a and common for canine parvovirus, feline panleukopenia virus and milk enteritis virus. Results of the studies demonstrated that all isolates tested represented CPV-2a antigenic type. Rapid antigenic strain replacement recorded by Parrish and Senda in the U.S.A and Japan was not confirmed in Poland. (author). 30 refs, 2 tabs

  12. Isolation of entomopathogenic nematodes and control of ...

    African Journals Online (AJOL)

    Jaime Ruiz

    when a new NE is isolated from field samples, laboratory assessments of ..... Tanks to Amanda Hodson, University of California at. Davis, for carrying out ... Manual of techniques in insect pathology. Academic Press, New York. Koppenhöfer A ...

  13. Isolation and characterization of a bacterial celluloseproducing ...

    African Journals Online (AJOL)

    year ripened persimmon vinegar, which belonged to the family of Acetobacteracea based on its morphological and physiological characteristics. The phylogenetic position of the isolated strain was most closely related to Gluconacetobacter ...

  14. Triterpene alcohol isolation from oil shale.

    Science.gov (United States)

    Albrecht, P; Ourisson, G

    1969-03-14

    Isoarborinol, an intact pentacyclic unsaturated alcohol, was isolated from the Messel oil shale (about 50 x 106 years old). Complex organic substances, even those very sensitive to oxidation, reduction, or acidic conditions, can thus survive without alteration for long periods.

  15. Cerveau isolé and pretrigeminal rats.

    Science.gov (United States)

    Zernicki, B; Gandolfo, G; Glin, L; Gottesmann, C

    1984-01-01

    Cortical and hippocampal EEG activity was analysed in 14 cerveau isole and 8 pretrigerninal rats. In the acute stage, waking EEG patterns were absent in the cerveau isole, whereas sleep EEG patterns were absent in the pretrigeminal preparations. However, already on the second day the EEG waking-sleep cycle recovered in the majority of rats. Paradoxically, stimuli directed to the caudal part of preparations evoked stronger cortical and hippocampal EEG arousal than olfactory and visual stimuli. The behavior of the caudal part was observed in 25 preparations. Although in abortive form, the rats did show some locomotor and grooming behavior, and could be fed orally. The peripheral events of paradoxical sleep appeared only on the fourth or fifth day of survival of the cerveau isole rats. It is concluded that the activity of the isolated cerebrum of the rat is similar to that of cat preparations, but that functions of the caudal neuraxis are superior in rats.

  16. Isolated neck-lifting procedure: isolated stork lift.

    Science.gov (United States)

    Barbarino, Sheila C; Wu, Allan Y; Morrow, David M

    2013-04-01

    Many patients desire cosmetic improvement of neck laxity when consulting with a plastic surgeon about their face. Neck laxity and loss of the cervicomental angle can be due to multiple components of aging such as skin quality/elasticity, loss of platysma muscle tone, and submental fat accumulation. Traditionally, the procedure of choice for patients with an aging lower face and neck is a cervicofacial rhytidectomy. However, occasionally, a patient wishes to have no other facial surgery than an improvement of their excessive skin of the anterior, lateral, and/or posterior neck. In other instances, a patient may present with having had a face/neck-lifting procedure that left objectionable vertical/diagonal lines at the lateral neck. In both these instances, a surgeon should consider an isolated stork lift (ISL) procedure. An ISL procedure avoids and/or corrects problematic vertical/diagonal lateral neck folds by "walking" the excess skin flaps around the posterior inferior occipital hairline bilaterally, bringing the flaps together at the lateral and posterior neck, which sometimes involves a midline posterior dart excision of the dog ear. A patient presenting with excessive skin of the neck (anterior, lateral, and/or posterior) and/or residual vertical/diagonal skin folds is an excellent candidate for the ISL. The ISL procedure was performed on 273 patients over a 2-year period at The Morrow Institute. Patients were included if they had excessive skin of the anterior, lateral, and/or posterior neck and/or diagonal/vertical lateral bands and did not desire a full face-lifting procedure. Patients were excluded from this study if they would not accept having longer hair in order to cover the scar along the posterior inferior occipital hairline or a midline T-flap skin closure scar at the base of the posterior midline neck. Under a combination of local anesthesia and IV sedation, a postauricular face-lift incision was made that was extended in a circumoccipital fashion

  17. Using Euler buckling springs for vibration isolation

    CERN Document Server

    Winterflood, J; Blair, D G

    2002-01-01

    Difficulties in obtaining ideal vertical vibration isolation with mechanical springs are identified as being due to the mass of the elastic element which is in turn due to its energy storage requirement. A new technique to minimize this energy is presented - being an Euler column undergoing elastic buckling. The design of a high performance vertical vibration isolation stage based on this technique is presented together with its measured performance.

  18. Using Euler buckling springs for vibration isolation

    International Nuclear Information System (INIS)

    Winterflood, J; Barber, T; Blair, D G

    2002-01-01

    Difficulties in obtaining ideal vertical vibration isolation with mechanical springs are identified as being due to the mass of the elastic element which is in turn due to its energy storage requirement. A new technique to minimize this energy is presented - being an Euler column undergoing elastic buckling. The design of a high performance vertical vibration isolation stage based on this technique is presented together with its measured performance

  19. Base isolation strategies for structures and components

    International Nuclear Information System (INIS)

    Varma, Veto; Reddy, G.R.; Vaze, K.K.; Kushwaha, H.S.

    2003-08-01

    In the present report the effect of laminated rubber bearing (LRB) system on the dynamic response of the structure was studied. A LRB system was designed and tested in the laboratory for its dynamic characteristics. Finite element analysis was also performed and based on this analysis, isolator for PHWR nuclear power plant was designed. Analysis of the building was performed with and without isolator. Comparison of responses was made in terms of frequencies, accelerations and displacements and floor response spectra. (author)

  20. Isolated rib fractures in geriatric patients

    OpenAIRE

    Elmistekawy, Elsayed M.; Hammad, Abd Almohsen M.

    2007-01-01

    Introduction: The goal of this study was to investigate the short-term outcomes in patients older than 60 years with isolated rib fractures and admitted to emergency hospital. Materials and Methods: This study included patients who were 60 years old or more and sustained blunt chest injury and had isolated rib fractures. The following data were obtained from the medical records: age, gender, number of fracture ribs, side of fracture ribs, mechanism and nature of injury, preexisting medical...

  1. Fault Detection and Isolation using Eigenstructure Assignment

    DEFF Research Database (Denmark)

    Jørgensen, R. B.; Patton, R.; Chen, J.

    1994-01-01

    The purpose of this article is to investigate the robustness to model uncertainties of observer based fault detection and isolation. The approach is designed with a straight forward dynamic nad the observer.......The purpose of this article is to investigate the robustness to model uncertainties of observer based fault detection and isolation. The approach is designed with a straight forward dynamic nad the observer....

  2. Isolation of avian influenza virus in Texas.

    Science.gov (United States)

    Glass, S E; Naqi, S A; Grumbles, L C

    1981-01-01

    An avian influenza virus with surface antigens similar to those of fowl plague virus (Hav 1 Nav 2) was isolated in 1979 from 2 commercial turkey flocks in Central Texas. Two flocks in contact with these infected flocks developed clinical signs, gross lesions, and seroconversion but yielded no virus. This was the first recorded incidence of clinical avian influenza in Texas turkeys and only the second time that an agent with these surface antigens was isolated from turkeys in U.S.

  3. Criteria: waste tank isolation and stabilization

    International Nuclear Information System (INIS)

    Metz, W.P.; Ogren, W.E.

    1976-09-01

    The crystallized Hanford high-level wastes stored in single-shell underground tanks consist of sludges and salt cakes covered with supernatural liquor. Purpose of stabilization and isolation is to reduce the releases and losses as a result of a loss of tank integrity. The tanks will be modified so that no inadvertent liquid additions can be made. Criteria for the isolation and stabilization are given and discussed briefly

  4. New approach for isolation of VNTR markers.

    OpenAIRE

    Nakamura, Y; Carlson, M; Krapcho, K; Kanamori, M; White, R

    1988-01-01

    Elsewhere we have reported an efficient method for isolating VNTR (Variable Number of Tandem Repeats) markers. Several of the VNTR markers isolated in those experiments were sequenced, and a DNA sequence of 9 bp (GNNGTGGG) emerged as an apparent consensus sequence for VNTR markers. To confirm this result and to develop more VNTR markers, we synthesized nine different 18-base-long oligonucleotides whose sequences each included GNNGTGGG. When 102 cosmid clones selected by these oligonucleotides...

  5. Probiotic features of two oral Lactobacillus isolates

    OpenAIRE

    Zavisic, Gordana; Petricevic, Sasa; Radulovic, Zeljka; Begovic, Jelena; Golic, Natasa; Topisirovic, Ljubisa; Strahinic, Ivana

    2012-01-01

    In this study, we checked lactobacilli strains of human origin for their potential as probiotic. Samples were collected from oral mucosa of 16 healthy individuals, out of which twenty isolates were obtained and two of them were selected and identified as Lactobacillus plantarum (G1) and L. casei (G3). Both isolates exhibited antagonistic action towards pathogenic microorganisms such as Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Salmonella abony, and Clostridium sporogene...

  6. Criteria: waste tank isolation and stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Metz, W.P.; Ogren, W.E.

    1976-09-01

    The crystallized Hanford high-level wastes stored in single-shell underground tanks consist of sludges and salt cakes covered with supernatural liquor. Purpose of stabilization and isolation is to reduce the releases and losses as a result of a loss of tank integrity. The tanks will be modified so that no inadvertent liquid additions can be made. Criteria for the isolation and stabilization are given and discussed briefly. (DLC)

  7. The supply solutions for isolated rural consumers

    International Nuclear Information System (INIS)

    Hazi, Gheorghe; Solomon, Petre; Hazi, Aneta

    2004-01-01

    This paper establishes the supply optimal solutions for isolated rural consumers. A complex technical-economical calculation method is developed for selection of the best solutions. This analysis is based on the minimization of the net present value, NPV, criterion. Using the results of this calculation, one can select easily the supply solution for a given active power and for a given distance separating the power source and the isolated consumer. (authors)

  8. Protein import into isolated pea root leucoplasts

    OpenAIRE

    Chu, Chiung-Chih; Li, Hsou-min

    2015-01-01

    Leucoplasts are important organelles for the synthesis and storage of starch, lipids and proteins. However, molecular mechanism of protein import into leucoplasts and how it differs from that of import into chloroplasts remain unknown. We used pea seedlings for both chloroplast and leucoplast isolations to compare within the same species. We further optimized the isolation and import conditions to improve import efficiency and to permit a quantitative comparison between the two plastid types....

  9. Genotoxicological Evaluation of NUTRALYS Pea Protein Isolate

    OpenAIRE

    Aouatif, Chentouf; Looten, Ph.; Parvathi, M. V. S.; Raja Ganesh, S.; Paranthaman, V.

    2013-01-01

    NUTRALYS Pea Protein Isolate, a protein supplement, is a high-quality source of protein which is primarily emulsifying functional protein. We evaluated the genotoxic potential of NUTRALYS isolated from dry yellow pea, using three established genotoxicity tests (AMES test in vitro chromosomal aberration test, and in vivo micronucleus test) employing OECD guidelines under GLP conditions. In the bacterial reverse mutation test, NUTRALYS did not show positive responses in strains detecting point ...

  10. Corynebacterium species isolated from patients with mastitis.

    Science.gov (United States)

    Paviour, Sue; Musaad, Sahar; Roberts, Sally; Taylor, Graeme; Taylor, Susan; Shore, Keith; Lang, Selwyn; Holland, David

    2002-12-01

    Corynebacteria were isolated from breast tissue, pus, or deep wound swabs of 24 women; the most common species isolated was the newly described Corynebacterium kroppenstedtii, followed by Corynebacterium amycolatum and Corynebacterium tuberculostearicum. Gram-positive bacilli were seen in samples sent for culture or in histological specimens for 12 women, and 9 of the 12 women from whom adequate histological specimens were obtained had conditions that met the criteria for granulomatous lobular mastitis, a chronic inflammatory disease of unknown etiology.

  11. Genome Analysis of the Biotechnologically Relevant Acidophilic Iron Oxidising Strain JA12 Indicates Phylogenetic and Metabolic Diversity within the Novel Genus “Ferrovum”

    Science.gov (United States)

    Ullrich, Sophie R.; Poehlein, Anja; Tischler, Judith S.; González, Carolina; Ossandon, Francisco J.; Daniel, Rolf; Holmes, David S.; Schlömann, Michael; Mühling, Martin

    2016-01-01

    Background Members of the genus “Ferrovum” are ubiquitously distributed in acid mine drainage (AMD) waters which are characterised by their high metal and sulfate loads. So far isolation and microbiological characterisation have only been successful for the designated type strain “Ferrovum myxofaciens” P3G. Thus, knowledge about physiological characteristics and the phylogeny of the genus “Ferrovum” is extremely scarce. Objective In order to access the wider genetic pool of the genus “Ferrovum” we sequenced the genome of a “Ferrovum”-containing mixed culture and successfully assembled the almost complete genome sequence of the novel “Ferrovum” strain JA12. Phylogeny and Lifestyle The genome-based phylogenetic analysis indicates that strain JA12 and the type strain represent two distinct “Ferrovum” species. “Ferrovum” strain JA12 is characterised by an unusually small genome in comparison to the type strain and other iron oxidising bacteria. The prediction of nutrient assimilation pathways suggests that “Ferrovum” strain JA12 maintains a chemolithoautotrophic lifestyle utilising carbon dioxide and bicarbonate, ammonium and urea, sulfate, phosphate and ferrous iron as carbon, nitrogen, sulfur, phosphorous and energy sources, respectively. Unique Metabolic Features The potential utilisation of urea by “Ferrovum” strain JA12 is moreover remarkable since it may furthermore represent a strategy among extreme acidophiles to cope with the acidic environment. Unlike other acidophilic chemolithoautotrophs “Ferrovum” strain JA12 exhibits a complete tricarboxylic acid cycle, a metabolic feature shared with the closer related neutrophilic iron oxidisers among the Betaproteobacteria including Sideroxydans lithotrophicus and Thiobacillus denitrificans. Furthermore, the absence of characteristic redox proteins involved in iron oxidation in the well-studied acidophiles Acidithiobacillus ferrooxidans (rusticyanin) and Acidithiobacillus

  12. Geographically isolated wetlands: Rethinking a misnomer

    Science.gov (United States)

    Mushet, David M.; Calhoun, Aram J.K.; Alexander, Laurie C.; Cohen, Matthew J.; DeKeyser, Edward S.; Fowler, Laurie G.; Lane, Charles R.; Lang, Megan W.; Rains, Mark C.; Walls, Susan

    2015-01-01

    We explore the category “geographically isolated wetlands” (GIWs; i.e., wetlands completely surrounded by uplands at the local scale) as used in the wetland sciences. As currently used, the GIW category (1) hampers scientific efforts by obscuring important hydrological and ecological differences among multiple wetland functional types, (2) aggregates wetlands in a manner not reflective of regulatory and management information needs, (3) implies wetlands so described are in some way “isolated,” an often incorrect implication, (4) is inconsistent with more broadly used and accepted concepts of “geographic isolation,” and (5) has injected unnecessary confusion into scientific investigations and discussions. Instead, we suggest other wetland classification systems offer more informative alternatives. For example, hydrogeomorphic (HGM) classes based on well-established scientific definitions account for wetland functional diversity thereby facilitating explorations into questions of connectivity without an a priori designation of “isolation.” Additionally, an HGM-type approach could be used in combination with terms reflective of current regulatory or policymaking needs. For those rare cases in which the condition of being surrounded by uplands is the relevant distinguishing characteristic, use of terminology that does not unnecessarily imply isolation (e.g., “upland embedded wetlands”) would help alleviate much confusion caused by the “geographically isolated wetlands” misnomer.

  13. Isolated vertigo and possibility of brain ischemia.

    Science.gov (United States)

    Mosarrezai, Arash; Toghae, Mansoureh; Majed, Masoud; Aloosh, Mehdi

    2012-08-01

    In cases of isolated vertigo, physicians are unable to definitely distinguish between central or peripheral vertigo by history and physical examination. Some central causes of isolated vertigo such as cerebellar stroke can be life-threatening and require intervention. Brain infarction can be detected shortly after the onset of clinical symptoms by using diffusion-weighted MRI (DWI). We have conducted this study to perform DWI on isolated vertigo patients with a higher probability of brain infarction. We enrolled 55 consecutive patients with isolated vertigo who had at least one cardiovascular risk factor. A questionnaire that consisted of cardiovascular risk factors was completed and DWI performed for each patient. We analyzed the association of cardiovascular risk factors with infarction as identified by DWI. Using DWI, 5 (9.1%) patients had an acute ischemic stroke. Among cardiovascular risk factors, analysis showed a significant relationship between diabetes mellitus (DM) and infarction. Isolated vertigo may occur due to the occlusion of a small artery in the area of brain circulated by the posterior inferior cerebellar artery. According to our results, DWI may be used in diabetic patients with isolated vertigo to locate a probable infarction.

  14. Isolation of cellulose microfibrils - An enzymatic approach

    Directory of Open Access Journals (Sweden)

    Sain, M.

    2006-11-01

    Full Text Available Isolation methods and applications of cellulose microfibrils are expanding rapidly due to environmental benefits and specific strength properties, especially in bio-composite science. In this research, we have success-fully developed and explored a novel bio-pretreatment for wood fibre that can substantially improve the microfibril yield, in comparison to current techniques used to isolate cellulose microfibrils. Microfibrils currently are isolated in the laboratory through a combination of high shear refining and cryocrushing. A high energy requirement of these procedures is hampering momentum in the direction of microfibril isolation on a sufficiently large scale to suit potential applications. Any attempt to loosen up the microfibrils by either complete or partial destruction of the hydrogen bonds before the mechanical process would be a step forward in the quest for economical isolation of cellulose microfibrils. Bleached kraft pulp was treated with OS1, a fungus isolated from Dutch Elm trees infected with Dutch elm disease, under different treatment conditions. The percentage yield of cellulose microfibrils, based on their diameter, showed a significant shift towards a lower diameter range after the high shear refining, compared to the yield of cellulose microfibrils from untreated fibres. The overall yield of cellulose microfibrils from the treated fibres did not show any sizeable decrease.

  15. Design experience on seismically isolated buildings

    International Nuclear Information System (INIS)

    Giuliani, G.C.

    1991-01-01

    This paper describes the practical problems associated with the structural design of seismically isolated buildings now under construction in Ancona, Italy. These structures are the first seismically isolated buildings in Italy. The Ancona region is in zone 2 of the Italian Seismic Code. It has a design acceleration of 0.07 g which corresponds to a ground surface acceleration of 0.25 g. The last significant earthquake was recorded on June 14, 1972, having a single shock-type wave with a peak acceleration of 0.53 g. Taking into account the aforesaid earthquake, the structural design of these new buildings was performed according to an acceleration spectrum which was different from the zone 2 seismic code and which provided protection for stronger ground motions. To minimize the cost of the structure, the buildings used ribbed plate decks, thus reducing the amount of material and the mass of the structures to be isolated. The design requirements, dynamic analysis performed, structural design, and practical engineering employed are reported in this paper. A comparison between the costs of a conventionally designed and a base-isolated structure is also reported. It shows a net savings of 7% for the base-isolated structure. The tests undertaken for certifying the mechanical properties of the isolators for both static and dynamic loads are also described, as is the full-scale dynamic test which is scheduled for next year (1990) for one of the completed buildings. (orig.)

  16. Design experience on seismically isolated buildings

    International Nuclear Information System (INIS)

    Giuliani, G.C.

    1989-01-01

    This paper describes the practical problems associated with the structural design of a group of seismically isolated buildings now under construction in Ancona, Italy. These structures are the first seismically isolated buildings in Italy. Taking into account previous earthquakes, the structural design of these new buildings was performed according to an acceleration spectrum which was different from its Zone 2 seismic code and which provided protection for stronger ground motions. To minimize the cost of the structure, the buildings used ribbed plate decks, thus reducing the amount of material and the mass of the structures to be isolated. The design requirements, dynamic analysis performed, structural design, and practical engineering employed are reported in this paper. A comparison between the costs of a conventionally designed and a base-isolated structure is also reported. The tests undertaken for certifying the mechanical properties of the isolators for both static and dynamic loads are also described, as is the full-scale dynamic test which is scheduled for next year (1990) for one of the completed buildings. Lessons learned in this design effort are potentially applicable to seismic base isolation for nuclear power plants

  17. The waste isolation safety assessment programme

    International Nuclear Information System (INIS)

    Brandstetter, A.; Harwell, M.A.

    1980-01-01

    Associated with commercial nuclear power production in the USA is the generation of potentially hazardous radioactive wastes. The Department of Energy (DOE), through the National Waste Terminal Storage (NWTS) Programme, is seeking to develop nuclear waste isolation systems in geologic formations that will preclude contact with the biosphere of waste radionuclides in concentrations which are sufficient to cause deleterious impact on humans or their environments. Comprehensive analyses of specific isolation systems are needed to assess the expectations of meeting that objective. The Waste Isolation Safety Assessment Programme (WISAP) has been established at the Pacific Northwest Laboratory (operated by Battelle Memorial Institute) for developing the capability of making those analyses. Among the analyses required for isolation system evaluation is the detailed assessment of the post-closure performance of nuclear waste repositories in geologic formations. This assessment is essential, since it is concerned with aspects of the nuclear power programme which previously have not been addressed. Specifically, the nature of the isolation systems (e.g. involving breach scenarios and transport through the geosphere), and the time-scales necessary for isolation, dictate the development, demonstration and application of novel assessment capabilities. The assessment methodology needs to be thorough, flexible, objective, and scientifically defensible. Further, the data utilized must be accurate, documented, reproducible, and based on sound scientific principles. (author)

  18. Xerophilic mycopopulations isolated from rapeseeds (Brassica napus

    Directory of Open Access Journals (Sweden)

    Škrinjar Marija M.

    2013-01-01

    Full Text Available This paper presents the results of an investigation related to mycological populations of rapeseed samples produced in the Institute of Field and Vegetable Crops in Novi Sad (location: Rimski Šančevi, Novi Sad, with a special emphasis on the potentially toxigenic mycopopulations. Mycological investigations were performed on the samples that were treated with 4% solution of Na-hypochlorite, and on the ones that were not submitted to this treatment. Isolation and determination of total mould count was carried out using Dichloran Glycerol Agar (DG18. The identification of isolated moulds was done according to modern keys for fungal determination. From 20 untreated tested samples, 17 were contaminated with moulds (10.0 to 4.7x102 cfu/g. When the samples were treated with 4% solution of Na-hypochlorite, moulds were isolated only form 4 samples, and the total mould count ranged from 10.0 to 60.0 cfu/g. In the isolated mycopopulations, xerophilic moulds dominated, especially those from the genera Aspergillus, Eurotium and Penicillium. In the isolated mycopopulations, high degree of isolated species belonged to toxigenic species from the genera Alternaria, Aspergillus, Fusarium, Eurotium and Penicillium. [Projekat Ministarstva nauke Republike Srbije, br. III46009 i br.TR31025

  19. Dissemination of clonal Salmonella enterica serovar Typhimurium isolates causing salmonellosis in Mauritius

    DEFF Research Database (Denmark)

    Issack, M. I.; Migura, Lourdes Garcia; Ramsamy, Veemala D.

    2013-01-01

    from foodborne illness outbreaks and sporadic gastroenteritis cases, four blood isolates, one postmortem colon isolate, 14 food isolates, and five poultry isolates. All isolates were pansusceptible to the 16 antibiotics tested, except for two isolates that were resistant to sulfamethoxazole...

  20. Isolation and Characterization of Pollulan Produced by a Local Isolate of Aureobasidium Pullulans

    OpenAIRE

    Kassim, Mohammad Bashir Ismail [محمد بشيراسماعيل قاسم

    2000-01-01

    A local isolate of Aureobasidium pullulans was obtained from fig leaves surface. The isolate was identified as A. pullulans on the basis of appearance of polymorphism in the colonies, melanin pigment and pullulan production in shake flask cultures. Pullulan production by the local isolate of A pullulans was two thirds of that produced by ATCC 42023. The studies of physico — chemical properties, chemical analysis, sugar composition periodate oxidation and smith degradation showed that the pull...

  1. Bacterial isolates from the bryozoan Membranipora membranacea: influence of culture media on isolation and antimicrobial activity.

    Science.gov (United States)

    Heindl, Herwig; Thiel, Vera; Wiese, Jutta; Imhoff, Johannes F

    2012-03-01

    From specimens of the bryozoan Membranipora membranacea collected in the Baltic Sea, bacteria were isolated on four different media, which significantly increased the diversity of the isolated groups. All isolates were classified according to 16S rRNA gene sequence analysis and tested for antimicrobial properties using a panel of five indicator strains and six different media. Each medium featured a unique set of isolated phylotypes, and a phylogenetically diverse collection of isolates was obtained. A total of 96 isolates were assigned to 49 phylotypes and 29 genera. Only one-third of the members of these genera had been isolated previously from comparable sources. The isolates were affiliated with Alpha- and Gammaproteobacteria, Bacilli, and Actinobacteria. A comparable large portion of up to 22 isolates, i.e., 15 phylotypes, probably represent new species. Likewise, 47 isolates (approximately 50%) displayed antibiotic activities, mostly against grampositive indicator strains. Of the active strains, 63.8 % had antibiotic traits only on one or two of the growth media, whereas only 12.7 % inhibited growth on five or all six media. The application of six different media for antimicrobial testing resulted in twice the number of positive hits as obtained with only a single medium. The use of different media for the isolation of bacteria as well as the variation of media considered suitable for the production of antibiotic substances significantly enhanced both the number of isolates obtained and the proportion of antibiotic active cultures. Thus the approach described herein offers an improved strategy in the search for new antibiotic compounds.

  2. SUSCEPTIBILITY OF RESPIRATORY ISOLATES OF STREPTOCOCCUS PNEUMONIAE ISOLATED FROM CHILDREN HOSPITALIZED IN THE CLINICAL CENTER NIS.

    Science.gov (United States)

    Dinić, Marina M; Mladenović Antić, Snezana; Kocić, Branislava; Stanković Dordević, Dobrila; Vrbić, Miodrag; Bogdanović, Milena

    2016-01-01

    Streptococcus pneumoniae is one of the most common causes of respiratory infections. The aim was to study the susceptibility to antimicrobial agents of respiratory isolates ofStreptococcus pneumoniae obtained from hospitalized children. A total of 190 respiratory pneumococcal isolates obtained from children aged from 0 to 14 years were isolated and identified by using standard microbiological methods. Susceptibility to oxacillin, erythromycin, clindamycin, tetracycline, cotrimoxazole, ofloxacin and rifampicin was tested by disc diffusion method. Minimal inhibitory concentrations for amoxicillin and ceftriaxone were determined by means of E test. The macrolide-resistant phenotype was detected by double disc diffusion test. All tested isolates were susceptible to amoxicillin and ceftriaxone. The minimal amoxicillin concentration inhibiting the growth of 50% of isolates and of 90% of isolates was 0.50 microg/ml and 1.0 microg/ml, respectively and the minimal ceftriaxone concentration inhibiting the growth of 50% of isolates and of 90% of isolates was 0.25 microg/ml and 0.50 microg/ml, respectively. Susceptibility to erythromycin and clindamycin was observed in 21.6% and 29.47% of isolates, respectively. The resistence to macrolides-M phenotype was detected in 10.07% of isolates and constitutive macrolide-lincosamide-streptogramin phenotype (constitutive MLS phenotype) was found in 89.93% of isolates. All tested isolates were susceptible to ofloxacin and rifampicin. Amoxicillin could be the therapy of choice in pediatric practice. The macrolides should not be recommended for the empirical therapy of pneumococcal respiratory tract infection in our local area.

  3. Single spore isolation and morphological characterization of local Malaysian isolates of rice blast fungus Magnoporthe grisea

    Science.gov (United States)

    Mishra, Ankitta; Ratnam, Wickneswari; Bhuiyan, Md Atiqur Rahman; Ponaya, Ariane; Jena, Khisord K.

    2015-09-01

    Rice blast is a destructive disease, caused by the fungal pathogen Magnaporthe grisea. It causes considerable damage to rice and leads to crop loss in rice growing regions worldwide. Although fungicides can be used to control rice blast, they generate additional cost in rice production and contamination of environment and food. Therefore, the use of resistant varieties is thought to be one of the most economically and environmentally efficient ways of crop protection from the disease. Six new local Malaysian isolates of M. grisea were isolated using single spore isolation method. Five isolates were from infected leaf samples collected from Kompleks Latihan MADA, Kedah and one was from Kelantan. These isolates were identified using morphological characteristics and microscopic studies and later confirmed by ITSequences. These isolates were induced to sporulate and used for greenhouse screening on two differential rice varieties: Mahsuri (susceptible) and Pongsu Seribu 2 (resistant). Among the 6 isolates, isolate number 3 was found to be the most virulent showing high sporulation while isolate number 4 was very slow growing, and the least virulent.

  4. Permanent isolation surface barrier development plan

    International Nuclear Information System (INIS)

    Wing, N.R.

    1994-01-01

    The exhumation and treatment of wastes may not always be the preferred alternative in the remediation of a waste site. In-place disposal alternatives, under certain circumstances, may be the most desirable alternatives to use in the protection of human health and the environment. The implementation of an in-place disposal alternative will likely require some type of protective covering that will provide long-term isolation of the wastes from the accessible environment. Even if the wastes are exhumed and treated, a long-term barrier may still be needed to adequately dispose of the treated wastes or any remaining waste residuals. Currently, no open-quotes provenclose quotes long-term barrier is available. The Hanford Site Permanent Isolation Surface Barrier Development Program (BDP) was organized to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site. The permanent isolation barrier technology also could be used at other sites. Permanent isolation barriers use engineered layers of natural materials to create an integrated structure with redundant protective features. Drawings of conceptual permanent isolation surface barriers are shown. The natural construction materials (e.g., fine soil, sand, gravel, riprap, asphalt) have been selected to optimize barrier performance and longevity. The objective of current designs is to use natural materials to develop a maintenance-free permanent isolation surface barrier that isolates wastes for a minimum of 1,000 years by limiting water drainage to near-zero amounts; reducing the likelihood of plant, animal, and human intrusion; controlling the exhalation of noxious gases; and minimizing erosion-related problems

  5. Permanent isolation surface barrier development plan

    Energy Technology Data Exchange (ETDEWEB)

    Wing, N.R.

    1994-01-01

    The exhumation and treatment of wastes may not always be the preferred alternative in the remediation of a waste site. In-place disposal alternatives, under certain circumstances, may be the most desirable alternatives to use in the protection of human health and the environment. The implementation of an in-place disposal alternative will likely require some type of protective covering that will provide long-term isolation of the wastes from the accessible environment. Even if the wastes are exhumed and treated, a long-term barrier may still be needed to adequately dispose of the treated wastes or any remaining waste residuals. Currently, no {open_quotes}proven{close_quotes} long-term barrier is available. The Hanford Site Permanent Isolation Surface Barrier Development Program (BDP) was organized to develop the technology needed to provide a long-term surface barrier capability for the Hanford Site. The permanent isolation barrier technology also could be used at other sites. Permanent isolation barriers use engineered layers of natural materials to create an integrated structure with redundant protective features. Drawings of conceptual permanent isolation surface barriers are shown. The natural construction materials (e.g., fine soil, sand, gravel, riprap, asphalt) have been selected to optimize barrier performance and longevity. The objective of current designs is to use natural materials to develop a maintenance-free permanent isolation surface barrier that isolates wastes for a minimum of 1,000 years by limiting water drainage to near-zero amounts; reducing the likelihood of plant, animal, and human intrusion; controlling the exhalation of noxious gases; and minimizing erosion-related problems.

  6. Performance assessment of nuclear waste isolation systems

    International Nuclear Information System (INIS)

    Lee, W.L.

    1984-01-01

    A number of concepts have been proposed for the isolation of highly radioactive wastes, and it will be necessary to demonstrate the safety of such systems. In many countries including the U.S., the waste isolation system of choice is deep mined geologic repositories. Because of the complex nature of the multiple isolation barriers afforded by mined geologic disposal systems, and the long isolation periods involved, this demonstration can only be indirect. In recent years this indirect demonstration, mostly through mathematical modeling, is called performance assessment. Performance Assessment can be defined to mean the development, testing, and application of a series of mathematical models and computer codes which traces the movement of radionuclides from a waste isolation system to the biosphere and any resultant dose to man. In modeling such a repository system, it is often convenient to divide it into a number of subsystems, there may be several different processes that need to be modeled, individually and interactively. For instance, this waste package will probably consist of a waste form such as borosilicate glass containing the radioisotopes, a canister, an overpack material such as steel or copper, and a buffer material such as bentonite. The processes to be modeled at the waste package scale include radioisotope inventory and decay, thermal radiation, radiolysis effects, corrosion, leading and fluid flow. In tracing radionuclide transport through rock, the processes of importance are probably groundwater flow, and sorption and retardation of radionuclide movement

  7. Seismic Analysis of a Viscoelastic Damping Isolator

    Directory of Open Access Journals (Sweden)

    Bo-Wun Huang

    2015-01-01

    Full Text Available Seismic prevention issues are discussed much more seriously around the world after Fukushima earthquake, Japan, April 2011, especially for those countries which are near the earthquake zone. Approximately 1.8×1012 kilograms of explosive energy will be released from a magnitude 9 earthquake. It destroys most of the unprotected infrastructure within several tens of miles in diameter from the epicenter. People can feel the earthquake even if living hundreds of miles away. This study is a seismic simulation analysis for an innovated and improved design of viscoelastic damping isolator, which can be more effectively applied to earthquake prevention and damage reduction of high-rise buildings, roads, bridges, power generation facilities, and so forth, from earthquake disaster. Solidworks graphic software is used to draw the 3D geometric model of the viscoelastic isolator. The dynamic behavior of the viscoelastic isolator through shock impact of specific earthquake loading, recorded by a seismometer, is obtained via ANSYS finite element package. The amplitude of the isolator is quickly reduced by the viscoelastic material in the device and is shown in a time response diagram. The result of this analysis can be a crucial reference when improving the design of a seismic isolator.

  8. Loneliness, Social Isolation, and Cardiovascular Health.

    Science.gov (United States)

    Xia, Ning; Li, Huige

    2018-03-20

    Social and demographic changes have led to an increased prevalence of loneliness and social isolation in modern society. Recent Advances: Population-based studies have demonstrated that both objective social isolation and the perception of social isolation (loneliness) are correlated with a higher risk of mortality and that both are clearly risk factors for cardiovascular disease (CVD). Lonely individuals have increased peripheral vascular resistance and elevated blood pressure. Socially isolated animals develop more atherosclerosis than those housed in groups. Molecular mechanisms responsible for the increased cardiovascular risk are poorly understood. In recent reports, loneliness and social stress were associated with activation of the hypothalamic-pituitary-adrenocortical axis and the sympathetic nervous system. Repeated and chronic social stress leads to glucocorticoid resistance, enhanced myelopoiesis, upregulated proinflammatory gene expression, and oxidative stress. However, the causal role of these mechanisms in the development of loneliness-associated CVD remains unclear. Elucidation of the molecular mechanisms of how CVD is induced by loneliness and social isolation requires additional studies. Understanding of the pathomechanisms is essential for the development of therapeutic strategies to prevent the detrimental effects of social stress on health. Antioxid. Redox Signal. 28, 837-851.

  9. A Multifunctional Isolated and Non-Isolated Dual Mode Converter for Renewable Energy Conversion Applications

    Directory of Open Access Journals (Sweden)

    Yiwang Wang

    2017-11-01

    Full Text Available In this paper, a multifunctional isolated and non-isolated dual-mode low-power converter was designed for renewable energy conversion applications such as photovoltaic power generation to achieve different operating modes under bi-directional electrical conversion. The proposed topology consists of a bidirectional non-isolated DC/DC circuit and an isolated converter with a high-frequency transformer, which merge the advantages of both the conventional isolated converter and non-isolated converter with the combination of the two converter technologies. Compared with traditional converters, the multifunctional converter can not only realize conventional bi-directional functions, but can also be applied for many different operation modes and meet the high output/input ratio demands with the two converter circuits operating together. A novel control algorithm was proposed to achieve the various functions of the proposed converter. An experimental platform based on the proposed circuit was established. Both the simulation and experimental results indicated that the proposed converter could provide isolated and non-isolated modes in different applications, which could meet different practical engineering requirements.

  10. Wire rope isolators for vibration isolation of equipment and structures – A review

    International Nuclear Information System (INIS)

    Balaji, P S; Rahman, M E; Lau, H H; Moussa, Leblouba

    2015-01-01

    Vibrations and shocks are studied using various techniques and analyzed to predict their detrimental effect on the equipment and structures. In cases, where the effects of vibration become unacceptable, it may cause structural damage and affect the operation of the equipment. Hence, adding a discrete system to isolate the vibration from source becomes necessary. The Wire Rope Isolator (WRI) can be used to effectively isolate the system from disturbing vibrations. The WRI is a type of passive isolator that exhibits nonlinear behavior. It consists of stranded wire rope held between two metal retainer bars and the metal wire rope is made up of individual wire strands that are in frictional contact with each other, hence, it is a kind of friction-type isolator. This paper compiles the research work on wire rope isolators. This paper presents the research work under two categories, namely monotonic and cyclic loading behaviors of WRI. The review also discusses the different terminologies associated with vibration isolation system and highlights the comparison between various isolation systems. (paper)

  11. Identity of streptococcal blood isolates and oral isolates from two patients with infective endocarditis

    DEFF Research Database (Denmark)

    Fiehn, N E; Gutschik, E; Larsen, Tove

    1995-01-01

    The purpose of this study was to isolate streptococcal strains from the oral cavities of streptococcal endocarditis patients and compare these strains biochemically and genetically with the corresponding streptococcal blood isolates. Total identity was observed between the blood and oral cavity...

  12. Isolation, Characterization and Identification of Environmental Bacterial Isolates with Screening for Antagonism Against Three Bacterial Targets

    Science.gov (United States)

    2017-04-01

    ISOLATES WITH SCREENING FOR ANTAGONISM AGAINST THREE BACTERIAL TARGETS 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...Identification of environmental isolates followed the flowchart from “Bergey’s Manual of Determinative Bacteriology” (Holt et al. 1994), which

  13. Medullary sponge kidney and isolated hemihyperplasia

    Directory of Open Access Journals (Sweden)

    P S Priyamvada

    2014-01-01

    Full Text Available The term hemihyperplasia refers to an enlargement of body parts beyond the normal asymmetry. Hemihyperplasia can be isolated or associated with various well-described malformation syndromes. Medullary sponge kidney (MSK has been described with isolated and syndromic hemihyperplasia; the actual prevalence is not known The hemi hypertrophy can be so subtle that it may be easily overlooked. MSK need not be limited to the side of hemihyperplasia - most often it is bilateral. Around 33 cases has been reported from different parts of the world of which 15 cases are isolated hemi hyperplasia (IHH, the remaining occurring in the context of various malformation syndromes So far only one case has been reported from India. We report a case of IHH involving right side of the body, recurrent renal stones, incomplete distal renal tubular acidosis hypercalciuria and imaging showing bilateral MSKs.

  14. Symbiodinium isolation by NaOH treatment.

    Science.gov (United States)

    Zamoum, Thamilla; Furla, Paola

    2012-11-15

    The presence of photosynthetic zooxanthellae (dinoflagellates) in the tissue of many cnidarians is the main reason for their ecological success (i.e. coral reefs). It could also be the main cause of their demise, as the worldwide bleaching of reef-building coral is nothing less than the breakdown of this symbiotic association. The stability of this relationship is the principal marker for the biomonitoring of cnidarian health. We have therefore developed a new, simple method to isolate zooxanthellae in a few steps using NaOH solution. The protocol was validated in three symbiotic cnidarian species: a sea anemone, a gorgonian and a coral. Our method allows the isolation of intact and viable zooxanthellae with better yields than classic methods, especially for species with a calcareous skeleton. Moreover, the isolated zooxanthellae were free of host nucleic contaminants, facilitating subsequent specific molecular analyses.

  15. Characterization of lactococci isolated from homemade kefir

    Directory of Open Access Journals (Sweden)

    Kojić M.

    2007-01-01

    Full Text Available Five bacteriocin-producing lactococci isolates from traditionally prepared kefir were determined as Lactococcus lactis subsp. lactis. The analyzed isolates showed different plasmid profiles and no cross inhibition between them was detected. Moreover, natural isolate BGKF26 was resistant to the antimicrobial activity of nisin producing strain NP45. Plasmid curing experiments revealed that the genes encoding bacteriocin and proteinase production are located on separate genetic elements, except in BGKF26. Production of the tested bacteriocins depends on the concentration of casitone or triptone in the medium. Higher concentrations of casitone or triptone induce bacteriocin activity. Our DNA-DNA hybridization analyses suggest that the analyzed antimicrobial compounds probably are lactococcin-like bacteriocins.

  16. Isolation of Salmonellae from Foods Samples

    Science.gov (United States)

    Taylor, Welton I.; Silliker, John H.

    1961-01-01

    A comparison of various methods of enhancing frequency of Salmonella isolations revealed that inoculation of a second enrichment broth, with culture from the first, was no improvement over the single direct enrichment method. It was inferior to centrifugation. Selenite was observed to produce more positive isolations at 48 hr than at 24. No change occurred in tetrathionate. Reconstitution of dried albumen with water produced a significant increase in isolations over direct inoculation of enrichment broth in the case of tetrathionate but not selenite broth. Pre-enrichment in lactose broth before inoculation of enrichment media was vastly superior to reconstitution in water for both enrichment broths. A comparison of results obtained using dulcitol, mannitol, lactose and carbohydrate-free purple broths in pre-enrichment indicated that the carbohydrate added was immaterial. PMID:13920002

  17. Development of novel Alicyclobacillus spp. isolation medium.

    Science.gov (United States)

    Chang, S; Kang, D-H

    2005-01-01

    To develop a new isolation medium with higher recovery rates of Alicyclobacillus spp. SK agar was developed with optimized incubation temperature, pH, acidulant, Tween 80 concentration and divalent cation addition. Results indicate that detection of Alicyclobacillus spp. by SK agar was significantly higher (P > 0.05) than those obtained by K agar, orange serum agar, and potato dextrose agar. Current media used for Alicyclobacillus spp. isolation still resulted in high numbers of false negative products. The sensitivity of SK agar to Alicyclobacillus spp. allows detection of low numbers of Alicyclobacillus spp. and also provides a more higher isolation results compared with currently used media. SK agar will be useful to the fruit juice industry to obtain more accurate numbers of contaminant Alicyclobacillus spp. With this media, false negative samples can be reduced, and the likelihood of exported products being rejected can be greatly reduced.

  18. MICROSCOPIC FUNGI ISOLATED FROM POLISH HONEY

    Directory of Open Access Journals (Sweden)

    Soňa Felšöciová

    2012-12-01

    Full Text Available The characterization of some honey samples from Poland was carried out on the basis of their microbiological (fungi and yeasts analysis. Most of the samples contained less than 20 % water. The amount of fungi found in the honey samples was less than 1 x 102 CFU.g-1 but 19 % of the samples had more yeasts than 1 x 102 CFU.g-1 – up to 5.7 x 102 CFU.g-1. The isolated fungi were Alternaria spp., Aspergillus spp., Cladosporium spp., Fusarium spp., Mycelia sterilia, Rhizopus spp. and Penicillium spp. The last genus was isolated very frequently. A total number of eight fungal Penicillium species were identified namely, Penicillium brevicompactum, P. commune, P. corylophilum, P. crustosum, P. expansum, P. griseofulvum, P. chrysogenum and P. polonicum. They were isolated using dilution plate method. The results showed that honeys produced in this region are of good microbiological quality.

  19. Increased cefepime MIC for enterobacteriacae clinical isolates.

    Science.gov (United States)

    Najafi, Narges; Alikhani, Ahmad; Babamahmoudi, Farhang; Davoudi, Alireza; Ghasemiyan, Roya; Aliyan, Shahriar; Shoujaiifar, Arman

    2013-01-01

    Background : Cefepime was used as empirical treatment in ventilator-associated pneumonia (VAP) induced by gram-negative and gram-positive bacteria. This study aimed to determine the antimicrobial susceptibility pattern of cefepime against microorganism causing VAP in Mazandaran, North of Iran. This study was performed on VAP patients diagnosed with clinical pulmonary infection score (CPIS) scores in ICU of two hospitals. For each patient suspected of having VAP, quantitative culture of endotracheal aspiration (QEA) was performed and MIC was determined by micro dilution test. Data were collected and analyzed. Thirty- five cases of enterobacteriaceae were isolated orderly including E coli 13, P. aeruginosa 11, Enterobacter 7 and K. pneumonia 4 cases. All the isolated E. coli, Enterobacter and Klebsiella, 54.5% of P. aeruginosa isolated were fully resistant to cefepime. The results of this study show that cefepime is not a reasonable choice for empirical treatment of nosocomial pneumonia and VAP.

  20. Isolated hepatic actinomycosis: a case report

    Directory of Open Access Journals (Sweden)

    Shehab Thomas M

    2010-02-01

    Full Text Available Abstract Introduction Actinomyces are slow growing, non-spore forming, gram-positive, branching bacilli that thrive in anaerobic and microareophilic conditions. Actinomyces are more commonly associated with oral and cervicofacial infections. Hepatic involvement in infections of the abdomen (known as isolated hepatic actinomycosis is rare, accounting for only 5% of all cases of actinomycosis. Case presentation We present the case of a 75-year-old Caucasian woman with a 3-month history of night sweats, fever, chills, abdominal bloating, anorexia, weight-loss, and early satiety. The patient was found to have isolated hepatic actinomycosis infection after undergoing a laparotomy with a biopsy of the liver. The patient has now recovered. Conclusion Isolated hepatic actinomycosis is a rare and often overlooked etiology for a liver mass. Given its subacute presentation and nondescript symptomatology, physicians should be aware of this differential and the potential pitfalls in diagnosis and management.

  1. THK: CLB Crossed Linear Bearing Seismic Isolators

    International Nuclear Information System (INIS)

    Toniolo, Roberto

    2008-01-01

    This text highlights the new seismic isolation technology called CLB (Crossed Linear Bearing), which is made of linear guides with recirculating steel ball technology. It describes specifications and building characteristics, provides examples of seismic isolation and application functionalities and shows experimental data. Since 1994, the constant commitment by Japan to develop diversified anti-seismic systems based on the precise needs of the structures to protect and the areas where they were built has led to the creation of important synergy between the research institutions of leading Japanese companies and THK's Centre for Research and Development. Their goal has been to develop new technology and solutions to allow seismic isolation to be effective in the following cases:

  2. Methods to isolate extracellular vesicles for diagnosis

    Science.gov (United States)

    Kang, Hyejin; Kim, Jiyoon; Park, Jaesung

    2017-12-01

    Extracellular vesicles (EVs) are small membrane-bound bodies that are released into extracellular space by diverse cells, and are found in body fluids like blood, urine and saliva. EVs contain RNA, DNA and proteins, which can be biomarkers for diagnosis. EVs can be obtained by minimally-invasive biopsy, so they are useful in disease diagnosis. High yield and purity contribute to precise diagnosis of disease, but damaged EVs and impurities can cause confu sed results. However, EV isolation methods have different yields and purities. Furthermore, the isolation method that is most suitable to maximize EV recovery efficiency depends on the experimental conditions. This review focuses on merits and demerits of several types of EV isolation methods, and provides examples of how to diagnose disease by exploiting information obtained by analysis of EVs.

  3. Prevalence and Biotyping of Pasteurella Haemolytica Isolates from ...

    African Journals Online (AJOL)

    P. haemolytica isolated from Sahel sheep and goat in Maiduguri was characterized phenotypically. A total of 92 P. haemolytica isolates were obtained from the nasopharyngeal swabs while a total of 15 isolates came from pneumonic lung samples. The results showed that 37(20.22%) P. haemolytica isolates were obtained ...

  4. Isolation and in vitro evaluation of bacteriophages against MDR-bacterial isolates from septic wound infections.

    Directory of Open Access Journals (Sweden)

    Roja Rani Pallavali

    Full Text Available Multi-drug resistance has become a major problem for the treatment of pathogenic bacterial infections. The use of bacteriophages is an attractive approach to overcome the problem of drug resistance in several pathogens that cause fatal diseases. Our study aimed to isolate multi drug resistant bacteria from patients with septic wounds and then isolate and apply bacteriophages in vitro as alternative therapeutic agents. Pus samples were aseptically collected from Rajiv Gandhi Institute of Medical Science (RIMS, Kadapa, A.P., and samples were analyzed by gram staining, evaluating morphological characteristics, and biochemical methods. MDR-bacterial strains were collected using the Kirby-Bauer disk diffusion method against a variety of antibiotics. Bacteriophages were collected and tested in vitro for lytic activity against MDR-bacterial isolates. Analysis of the pus swab samples revealed that the most of the isolates detected had Pseudomonas aeruginosa as the predominant bacterium, followed by Staphylococcus aureus, Klebsiella pneumoniae and Escherichia coli. Our results suggested that gram-negative bacteria were more predominant than gram-positive bacteria in septic wounds; most of these isolates were resistant to ampicillin, amoxicillin, penicillin, vancomycin and tetracycline. All the gram-positive isolates (100% were multi-drug resistant, whereas 86% of the gram-negative isolates had a drug resistant nature. Further bacteriophages isolated from sewage demonstrated perfect lytic activity against the multi-drug resistant bacteria causing septic wounds. In vitro analysis of the isolated bacteriophages demonstrated perfect lysis against the corresponding MDR-bacteria, and these isolated phages may be promising as a first choice for prophylaxis against wound sepsis, Moreover, phage therapy does not enhance multi-drug resistance in bacteria and could work simultaneously on a wide variety of MDR-bacteria when used in a bacteriophage cocktail. Hence

  5. Doubts and Concerns about Isolated Maternal Hypothyroxinemia

    Directory of Open Access Journals (Sweden)

    Mariacarla Moleti

    2011-01-01

    Full Text Available There is evidence that isolated maternal hypothyroxinemia may have detrimental effects on both mother and foetus. Nonetheless, this condition is still far from being universally accepted as a separate thyroid disease, and a standard definition of this state of mild thyroid underfunction is still lacking. We will review the biochemical criteria used to define isolated maternal hypothyroxinemia, together with current methodological issues related to FT4 assays. We will also discuss its epidemiological impact in both iodine-deficient and-sufficient areas, and the effectiveness of iodine prophylaxis on maternal thyroid function and neuropsychomotor development in offspring.

  6. [Isolated thyroid gland sarcoidosis and hyperthyroidism].

    Science.gov (United States)

    Langsteger, W; Lind, P; Beham, A; Költringer, P; Eber, O

    1989-04-29

    A case of isolated sarcoidosis of the thyroid gland, associated with hyperthyroidism, is reported in a 28-year-old male patient whose thyroid was removed for hyperthyroid multinodular goitre. Histology revealed a regressive adenoma and sarcoidosis in non-adenomatous thyroid residue. Further diagnosis, therapeutic management and a 3-year follow-up did not disclose any specific changes or involvement of other tissues. Isolated thyroidal sarcoidosis with hyperthyroid alterations are extremely rare and mostly chance findings; simultaneous occurrence of thyroid sarcoidosis and hyperthyroidism may be a symptom of gland infiltration for which an adequate explanation is still lacking.

  7. Experimental chaos in nonlinear vibration isolation system

    International Nuclear Information System (INIS)

    Lou Jingjun; Zhu Shijian; He Lin; He Qiwei

    2009-01-01

    The chaotic vibration isolation method was studied thoroughly from an experimental perspective. The nonlinear load-deflection characteristic of the conical coil spring used in the experiment was surveyed. Chaos and subharmonic responses including period-2 and period-6 motions were observed. The line spectrum reduction and the drop of the acceleration vibration level in chaotic state and that in non-chaotic state were compared, respectively. It was concluded from the experiment that the nonlinear vibration isolation system in chaotic state has strong ability in line spectrum reduction.

  8. Reliability analysis of containment isolation systems

    International Nuclear Information System (INIS)

    Pelto, P.J.; Counts, C.A.

    1984-06-01

    The Pacific Northwest Laboratory (PNL) is reviewing available information on containment systems design, operating experience, and related research as part of a project being conducted by the Division of Systems Integration, US Nuclear Regulatory Commission. The basic objective of this work is to collect and consolidate data relevant to assessing the functional performance of containment isolation systems and to use this data to the extent possible to characterize containment isolation system reliability for selected reference designs. This paper summarizes the results from initial efforts which focused on collection of data from available documents and briefly describes detailed review and analysis efforts which commenced recently. 5 references

  9. Vaginal Lactobacillus isolates inhibit uropathogenic Escherichia coli.

    OpenAIRE

    Atassi , Fabrice; Brassart , Dominique; Grob , Philipp; Graf , Federico; Servin , Alain ,

    2006-01-01

    The purpose of this study was to investigate the antibacterial activities of Lactobacillus jensenii KS119.1 and KS121.1, and Lactobacillus gasserii KS120.1 and KS124.3 strains isolated from the vaginal microflora of healthy women, against uropathogenic, diffusely adhering Afa/Dr Escherichia coli (Afa/Dr DAEC) strains IH11128 and 7372 involved in recurrent cystitis. We observed that some of the Lactobacillus isolates inhibited the growth and decreased the viability of E. coli IH11128 and 7372....

  10. Function analysis of steam isolation valves

    International Nuclear Information System (INIS)

    Persson, R.; Kilpi, K.; Noro, H.; Siikonen, T.; Sjoeberg, A.; Wallen, G.; Aakesson, H.

    1981-01-01

    Function analysis of system-medium-operated steam isolation valves has been the objective of the Swedish-Finnish IVLS project, the results of which are presented in this report. Theoretical models were to be verified against available experimental data, to some extent from the HDR blowdown experiments, which are part of a German reactor safety program. Finnish hydraulic measurements on a valve model (scale 1:2.15) have been performed to give complementary data. The analysis work has covered the thermal-hydraulic behaviour of steam isolation valves as well as phenomena related to structural mechanics. Work performed under contract with the Swedish Nuclear Power Inspectorate. (Author)

  11. Function analysis of steam isolation valves

    International Nuclear Information System (INIS)

    Persson, R.; Sjoeberg, A.; Aakesson, H.; Kilpi, K.; Noro, H.; Siikonen, T.; Wallen, G.

    1981-01-01

    Function analysis of system-medium-operated steam isolation valves has been the objective of the Swedish-Finnish IVLS project, the results of which are presented in this report. Theoretical models were to be verified against available experimental data, to some extent from the HDR blowdown experiments, which are part of a German reactor safety program. Finnish hydraulic measurements on a valve model (scale 1:2.15) have been performed to give complementary data. The analysis work has covered the thermal-hydraulic behaviour of steam isolation valves as well as phenomena related to structural mechanics. (Auth.)

  12. Axenic isolation of viable Giardia muris trophozoites.

    Science.gov (United States)

    Tillotson, K D; Buret, A; Olson, M E

    1991-06-01

    Large numbers of viable Giardia muris trophozoites were isolated from the duodenum of experimentally infected mice 6 days after inoculation with 1,000 G. muris cysts. A series of shaking, incubation, and washing steps in the presence of the broad-spectrum antibiotic piperacillin readily provided 4.9 +/- 1.5 x 10(5) G. muris trophozoites per mouse, free of detectable contaminant organisms. Anaerobic and microaerophilic culturing and scanning electron microscopy demonstrated axenic status and high purity of the isolates. The viability of trophozoites was 98 +/- 2%. Application of this technique should permit novel immunological and epidemiological analyses of G. muris infection and biochemical investigations of this protozoan parasite.

  13. BIOLOGICAL CLONING OF A BOVINE CORONAVIRUS ISOLATE

    OpenAIRE

    Betancourt, A; Rodríguez, Edisleidy; Relova, Damarys; Barrera, Maritza

    2008-01-01

    Con el objetivo de obtener un aislado de Coronavirus bovino clonado biológicamente se adaptó el aislado VB73/04 a la multiplicación en la línea celular MDBK. Este aislado indujo la formación de placas, las cuales resultaron homogéneas después del clonaje biológico. La población viral obtenida fue identificada como Coronavirus bovino por RT-PCR y Seroneutralización. In order to obtain a biologically cloned bovine coronavirus isolate, the isolate VB73/04 was adapted to multiplication in MDBK...

  14. Properties of Oryctes Baculovirus Isolated in Indonesia

    Directory of Open Access Journals (Sweden)

    Jun Kobayashi

    1995-12-01

    Full Text Available An Indonesian isolate of Oryctes baculovirus was purified from infected midguts of the rhinoceros beetle (Oryctes rhinoceros by centrifugation on a 10–40% (w/v sucroese gradient. Morphological features of  nucleocapsid including a tail-like projection were very same as those previously reported. Both protein components of purified particles and restriction fragment electrophoresis profiles of viral DNA were similar to those of their isolates of Oryctes baculovirus, although there were some differences. Key words: Baculovirus oryctes, electrophoresis

  15. Seismic isolation systems designed with distinct multiple frequencies

    International Nuclear Information System (INIS)

    Wu, Ting-shu; Seidensticker, R.W.

    1991-01-01

    Two systems for seismic base isolation are presented. The main feature of these system is that, instead of only one isolation frequency as in conventional isolation systems, they are designed to have two distinct isolation frequencies. When the responses during an earthquake exceed the design value(s), the system will automatically and passively shift to the secondly isolation frequency. Responses of these two systems to different ground motions including a harmonic motion with frequency same as the primary isolation frequency, show that no excessive amplification will occur. Adoption of these new systems certainly will greatly enhance the safety and reliability of an isolated superstructure against future strong earthquakes. 3 refs

  16. Age-related associative deficits and the isolation effect.

    Science.gov (United States)

    Badham, Stephen P; Maylor, Elizabeth A

    2013-01-01

    If all but one of the items in a list are similar (e.g., all black except one red), memory for the different item is enhanced (the isolation effect). Older adults generally show similar or smaller isolation effects compared to young adults, which has been attributed to age-related deficits in associative memory whereby older adults are less able to associate an isolated stimulus to its isolating feature. Experiment 1 examined the isolation effect for isolation based on spatial position, modality and color; in Experiment 2, the criterion for isolation was the associative relation between stimuli. The results consistently showed no differences between young and older participants in the magnitude of the isolation effect. Whilst age deficits in associative memory may act to reduce the isolation effect in older adults, age deficits in self-initiated processing and inhibitory functionality may counteract this reduction by enhancing the isolation effect in older adults.

  17. K. OXYTOCA BACTERIOPHAGES ISOLATION METHODS IMPROVEMENT

    Directory of Open Access Journals (Sweden)

    G. R. Sadrtdinova

    2017-01-01

    Full Text Available The article presents the results of a study related to increasing the efficiency of phage isolation of bacteria of the species K. oxytoca, by developing the optimal composition of the medium used in the work. In scientific research, in almost all methods associated with the isolation of bacteriophages, meat-peptone broth and meat-peptone agar are used as the nutrient basis. The peculiarities of growth and cultivation of microorganisms create certain difficulties for the isolation of phages active against bacteria of the species K. oxytoca. The selection of components and the creation of an environment that would ensure the optimal growth of both the bacterial culture and the reproduction of the virus makes it possible to facilitate the isolation of bacteriophages. The number of bacterial strains used in the work was 7. All strains of cultures were obtained from the Museum of the Department of Microbiology, Virology, Epizootology and Veterinary and Sanitary Expertise of the Federal State Budget Educational Institution of Higher Education “Ulyanovsk State Agrarian University named after P.A. Stolypin”. The studies included 2 main stages. The first stage consisted in isolation of bacteriophages by the method of isolation from the external environment by the method of Adelson L.I., Lyashenko E.A. The material for the studies were samples: soil, sewage sample, fecal samples (2. Only 4 samples. According to the chosen method, the sowing of the putative phagolysate was carried out on meat-peptone agar (1.5% and the agar for isolating bacteriophages (Aph (1.5%. A positive result was the presence on the environment of negative colonies, clearly visible on the matt background of deep growth of bacteria. A negative result is a continuous growth (“lawn” of bacterial culture. As a control, the culture of the microorganism studied was used for the media. In the course of the conducted studies for the first stage, 2 bacteriophages were isolated, active

  18. Virulence of Rhodococcus equi Isolated from Cats and Dogs

    OpenAIRE

    Takai, Shinji; Martens, Ronald J.; Julian, Alan; Garcia Ribeiro, Márcio; Rodrigues de Farias, Marconi; Sasaki, Yukako; Inuzuka, Kazuho; Kakuda, Tsutomu; Tsubaki, Shiro; Prescott, John F.

    2003-01-01

    Nine cat isolates and nine dog isolates of Rhodococcus equi from clinical material were investigated for the presence of the virulence-associated antigens (VapA and VapB) and virulence plasmids. Five of the cat isolates and one dog isolate were VapA positive and contained an 85-kb type I or an 87-kb type I plasmid. The remaining 12 isolates were avirulent R. equi strains and contained no virulence plasmids.

  19. Bioprocessing of coal - 10 - an application of microbial flotation to mineral processing

    Energy Technology Data Exchange (ETDEWEB)

    Nagaoka, T. [and others] [CRIEPI, Abiko-shi (Japan). Abiko Research Lab.

    1996-09-01

    Microbial flotation for coal desulfurization is being developed. Pyrite in coal is removed by bacterial adhesion by changing the surface property of pyrite. The bacterial adhesion of Thiobacillus ferrooxidans to sulfide minerals (pyrite, galena, molybdenite, chalcocite and millerite), and pyrite removal from the mixture of these sulfide minerals by microbial flotation was investigated. To compare the adhesion of T. ferrooxidans to pyrite with that to the other four minerals mentioned, the surface areas of the minerals, where the bacterium could adhere, was measured. It was observed that the roughness on the mineral surfaces was much smaller than the size of the bacterial cells. Hence, it was suggested that the roughness did not affect the bacterial adhesion to mineral surfaces. Bacterial adhesion to pyrite was compared with that to the other minerals. The amount of adhering bacterium was estimated on the basis of the adherable surface area measured with microscopic method. The amount of adhering cells to pyrite was 421.6 x 10{sup 8} cells/cm{sup 2}. On the other hand, the amounts of adhering cells to the minerals, except for pyrite were in a range of 77.1 to 160.8 x 10{sup 8} cells/cm{sup 2}. The bacterium adheres more to pyrite than to the other minerals, and only adheres to pyrite even if the pyrite is mixed with other minerals. Hence, T. ferrooxidans could adhere selectively to pyrite. Pyrite removal from the mineral mixtures was investigated with microbial flotation. Pyrite removal was in a range of 83.7% to 95.1% and mineral recovery was 72.9% to 100%. The grade of recovered minerals was in a range of 79.2 to 86.0% and that of rejected pyrite was in a range of 78.7 to 90.0%. These results suggest that microbial flotation can be a novel technology for mineral processing.

  20. Static and dynamic stability of pneumatic vibration isolators and systems of isolators

    Science.gov (United States)

    Ryaboy, Vyacheslav M.

    2014-01-01

    Pneumatic vibration isolation is the most widespread effective method for creating vibration-free environments that are vital for precise experiments and manufacturing operations in optoelectronics, life sciences, microelectronics, nanotechnology and other areas. The modeling and design principles of a dual-chamber pneumatic vibration isolator, basically established a few decades ago, continue to attract attention of researchers. On the other hand, behavior of systems of such isolators was never explained in the literature in sufficient detail. This paper covers a range of questions essential for understanding the mechanics of pneumatic isolation systems from both design and application perspectives. The theory and a model of a single standalone isolator are presented in concise form necessary for subsequent analysis. Then the dynamics of a system of isolators supporting a payload is considered with main attention directed to two aspects of their behavior: first, the static stability of payloads with high positions of the center of gravity; second, dynamic stability of the feedback system formed by mechanical leveling valves. The direct method of calculating the maximum stable position of the center of gravity is presented and illustrated by three-dimensional stability domains; analytic formulas are given that delineate these domains. A numerical method for feedback stability analysis of self-leveling valve systems is given, and the results are compared with the analytical estimates for a single isolator. The relation between the static and dynamic phenomena is discussed.

  1. Discrete optimization of isolator locations for vibration isolation systems: An analytical and experimental investigation

    Energy Technology Data Exchange (ETDEWEB)

    Ponslet, E.R.; Eldred, M.S. [Sandia National Labs., Albuquerque, NM (United States). Structural Dynamics Dept.

    1996-05-17

    An analytical and experimental study is conducted to investigate the effect of isolator locations on the effectiveness of vibration isolation systems. The study uses isolators with fixed properties and evaluates potential improvements to the isolation system that can be achieved by optimizing isolator locations. Because the available locations for the isolators are discrete in this application, a Genetic Algorithm (GA) is used as the optimization method. The system is modeled in MATLAB{trademark} and coupled with the GA available in the DAKOTA optimization toolkit under development at Sandia National Laboratories. Design constraints dictated by hardware and experimental limitations are implemented through penalty function techniques. A series of GA runs reveal difficulties in the search on this heavily constrained, multimodal, discrete problem. However, the GA runs provide a variety of optimized designs with predicted performance from 30 to 70 times better than a baseline configuration. An alternate approach is also tested on this problem: it uses continuous optimization, followed by rounding of the solution to neighboring discrete configurations. Results show that this approach leads to either infeasible or poor designs. Finally, a number of optimized designs obtained from the GA searches are tested in the laboratory and compared to the baseline design. These experimental results show a 7 to 46 times improvement in vibration isolation from the baseline configuration.

  2. Water splitting: Taking cobalt in isolation

    Science.gov (United States)

    Wang, Aiqin; Zhang, Tao

    2016-01-01

    The sustainable production of hydrogen is key to the delivery of clean energy in a hydrogen economy; however, lower-cost alternatives to platinum electrocatalysts are needed. Now, isolated, earth-abundant cobalt atoms dispersed over nitrogen-doped graphene are shown to efficiently electrolyse water to generate hydrogen.

  3. Immunomodulatory Potential of Patchouli Alcohol Isolated from ...

    African Journals Online (AJOL)

    Purpose: To isolate and purify patchouli alcohol (PA), a tricyclic sesquiterpene constituent of Pogostemon cablin, and investigate its immunomodulatory potential in Kunming mice. Methods: PA was prepared from an ethanol aqueous extract of P. cablin by silica gel column chromatography, and further purified by ...

  4. Isolated Enteric Cyst in the Neck

    Directory of Open Access Journals (Sweden)

    Amit Mahore

    2014-01-01

    Full Text Available We report an extremely rare case of isolated enteric cyst in the neck region which was diagnosed on the histopathological examination. It was suspected to be duplication cyst on radiology. We have also evaluated the differential diagnosis and management issues.

  5. Biodegradation of norfloxacin by Penicillium frequentans isolated ...

    African Journals Online (AJOL)

    One norfloxacin-degrading fungi was isolated from soil contaminated by norfloxacin and preliminary identified as Penicillium frequentans. Indoor simulative degradation experiments were carried out to investigate the biodegradation kinetics of norfloxacin with or without NFX3 in soil. The results indicate that the ...

  6. Secondary wastewater treatment by microalgae isolated from ...

    African Journals Online (AJOL)

    Microalgae play a fundamental role in primary and secondary wastewater treatment. In this work the growth, photosynthetic activity and removal of phosphorus from wastewater effluents by indigenous blue-green algal species, Spirulina and Oscillatoria, isolated from Gaborone oxidation ponds was studied. Oscillatoria and ...

  7. Isolated microalbuminuria indicates a poor medical prognosis

    NARCIS (Netherlands)

    Scheven, Lieneke; Van der Velde, Marije; Heerspink, Hiddo J. Lambers; De Jong, Paul E.; Gansevoort, Ron T.

    Background. Microalbuminuria is often regarded as a sign of end-organ damage due to diabetes and/or hypertension, and as such to be associated with an increased risk for cardiovascular events. It has been questioned whether isolated microalbuminuria, that is microalbuminuria in the absence of a

  8. Campylobacter iguaniorum sp. nov., isolated from reptiles

    Science.gov (United States)

    During samplings of reptiles for Epsilonproteobacteria, Campylobacter strains were isolated from lizards and chelonians not belonging to any of the established taxa. Initial AFLP, PCR, and 16S rRNA sequence analysis showed that these strains were most closely related to Campylobacter fetus and Campy...

  9. Antimicrobial substances produced by bacteria isolated from ...

    African Journals Online (AJOL)

    SERVER

    2007-08-06

    Aug 6, 2007 ... We report here the preliminary antimicrobial activity of substances produced by Bacillus subtilis NB-6. (air flora isolate) ... Key words: Antimicrobial activity, Bacillus, Burkholderia, Corynebacterium, methicillin-resistant Staphylococcus aureus. .... products contaminated with animal MRSA is very plausible ...

  10. Densitometric HPTLC quantification of asiaticoside isolated from ...

    African Journals Online (AJOL)

    Asiaticoside isolated from Centella asiatica has been found through in vitro test to serve as an active agent of healing on wounds. To quantify this compound in Centella asiatica cultivated in Benin, a new, simple and rapid High-Performance Thin-Layer Chromatography (HPTLC) method was developed and validated for its ...

  11. Site identification presentation: Basalt Waste Isolation Project

    International Nuclear Information System (INIS)

    1979-11-01

    The final step in the site identification process for the Basalt Waste Isolation Project is described. The candidate sites are identified. The site identification methodology is presented. The general objectives which must be met in selecting the final site are listed. Considerations used in the screening process are also listed. Summary tables of the guidelines used are included

  12. Isolation of glycoproteins from brown algae

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a novel process for the isolation of unique anti-oxidative glycoproteins from the pH precipitated fractions of enzymatic extracts of brown algae. Two brown seaweeds viz, Fucus serratus and Fucus vesiculosus were hydrolysed by using 3 enzymes viz, Alcalase, Viscozyme...

  13. Isolated prompt photon production at CDF

    International Nuclear Information System (INIS)

    Maas, P.A.

    1992-11-01

    This note describes measurements of isolated prompt photon production at √s = 1.8 TeV using the CDF experiment. The measurements are compared to recent NLO QCD calculations, including recently obtained parton distribution functions. Qualitatively, the QCD calculation with the new parton distribution functions agrees better with the data than the previous parton distribution functions

  14. Multiple antibiotics resistant among environmental isolates of ...

    African Journals Online (AJOL)

    In this study we assessed the functionality of integrons, melanin-like pigment and biofilm formation on multidrug resistance among environmental isolates of Stenotrophomonas maltophilia. Marked resistances were noted against aztreonam (60%), cefepime (68%), ceftazidime (77%), ciprofloxacin (72%), gentamicin (65%), ...

  15. Antidepressant screening and flavonoids isolation from ...

    African Journals Online (AJOL)

    Eremostachys laciniata (L) Bunge (Lamiaceae), a rich source of flavonoids, has been investigated for chemical constituents and in vivo antidepressant property using forced swim test (FST) model. Five important compounds were isolated, including luteolin (1), apigenin (2), 5,8-dihydroxy-6,7- dimethoxyflavone (3), 5 ...

  16. Back to basics: hand hygiene and isolation

    Science.gov (United States)

    Lin Huang, G. Khai; Stewardson, Andrew J.; Lindsay Grayson, M.

    2014-01-01

    Purpose of review Hand hygiene and isolation are basic, but very effective, means of preventing the spread of pathogens in healthcare. Although the principle may be straightforward, this review highlights some of the controversies regarding the implementation and efficacy of these interventions. Recent findings Hand hygiene compliance is an accepted measure of quality and safety in many countries. The evidence for the efficacy of hand hygiene in directly reducing rates of hospital-acquired infections has strengthened in recent years, particularly in terms of reduced rates of staphylococcal sepsis. Defining the key components of effective implementation strategies and the ideal method(s) of assessing hand hygiene compliance are dependent on a range of factors associated with the healthcare system. Although patient isolation continues to be an important strategy, particularly in outbreaks, it also has some limitations and can be associated with negative effects. Recent detailed molecular epidemiology studies of key healthcare-acquired pathogens have questioned the true efficacy of isolation, alone as an effective method for the routine prevention of disease transmission. Summary Hand hygiene and isolation are key components of basic infection control. Recent insights into the benefits, limitations and even adverse effects of these interventions are important for their optimal implementation. PMID:24945613

  17. Isolation and characterization of two malathiondegrading ...

    African Journals Online (AJOL)

    Pseudomonas aeruginosa and Pseudomonas mendocina degrading malathion were studied. Morphological, biochemical and 16S rRNA genes for bacterial identification were selected. Biodegradation of some organophosphorus compounds with the 2 bacterial isolates was determined by high performance liquid ...

  18. DNA isolation from rat tail or ear

    NARCIS (Netherlands)

    Cuppen, E.

    2010-01-01

    This protocol describes a rapid procedure for isolating DNA from rat tail or ear punches. The simplest version of the protocol can be scaled for use in 96-well (deep-well) plates. The quality of the DNA is sufficient for any polymerase chain reaction (PCR)-based genotyping approach.

  19. The Unpopular Issues of Poverty and Isolation.

    Science.gov (United States)

    Hunter, Bruce

    2000-01-01

    Nearly every state shortchanges poor and geographically isolated children. It is unpopular to spend on the neediest. Instead of fully funding Title 1 and The Individuals with Disabilities Education Act, Congress and President Clinton construct new competitive, general grant programs available to middle-class communities. (MLH)

  20. isolation and characterization of keratinase producing marine ...

    African Journals Online (AJOL)

    Dr.NGPASC

    Department of Biotechnology, Dr. N.G.P. Arts and Science College, Coimbatore – 48, Tamilnadu, India. Accepted 2 October, 2012. A unique standard starch casein medium has been implemented for the isolation of actinobacteria from the south Indian ... INTRODUCTION. Keratin is an insoluble protein which is resistant to.

  1. Chromium Tolerance and Bioremoval by Cyanobacteria Isolated ...

    African Journals Online (AJOL)

    Two cyanobacterial species Nostoc calcicola HH-12 and Chroococcus minutus HH-11 isolated from a textile mill oxidation pond were examined individually and as consortium for their chromium(VI) tolerance and bioremoval from aqueous solutions. Both species were tolerant to the metal and showed significant increase ...

  2. dichlorophenoxyacetic acid by bacteria species isolated from ...

    African Journals Online (AJOL)

    SERVER

    2007-06-18

    Jun 18, 2007 ... released/mg protein)-1 h-1] in actively growing cell cultures ranged from 0.010 – 0.055 (SERU 2) and .... concentration of the extracts was estimated by the Biuret method. (Gornall et al., 1949) using bovine serum albumin as the standard ... free culture extract of the isolates against 2,4-D were determined by.

  3. Phenotypic and Genotypic Characterization of Nosocomial Isolates ...

    African Journals Online (AJOL)

    The overall resistance of MRSA to a variety of antibiotics tested was linezolid, 48.7 %; ciprofloxacin, 15.3 %; sulfamethoxazole/trimethoprim (TMS), 14.0 %; gentamicin, 12.7 %; and rifampicin, 6.7 %. All MRSA isolates were positive for femB and mecA genes; one MSSA carried mecA gene. Conclusion: Since S. aureus ...

  4. Antibiotic Sensitivity Pattern of Microorganisms Isolated from ...

    African Journals Online (AJOL)

    Antibiotic sensitivity pattern of microorganisms isolated from smoked and frozen fishes sold in Benin and Warri metropolis were investigated. Adopting microbiological standard techniques, the results of the bacterial counts and fungal counts ranged from 5.4 x 106 (Ekpan market) to 25.1 x 106 (Ekpan market) and 1.1 x 105 ...

  5. Organic fragments from graphene oxide: Isolation, characterization ...

    Indian Academy of Sciences (India)

    in water.6 In recent years, several groups have reported ... ticles were termed as base-treated GO (BGO). ... we isolated debris formed from aq-NH3-treated GO .... under aqueous basic conditions (green ball—carbon in GO basal plane; grey.

  6. Corynebacterium macginleyi isolated from a corneal ulcer

    Directory of Open Access Journals (Sweden)

    Kathryn Ruoff

    2010-02-01

    Full Text Available We report the isolation of Corynebacterium macginleyi from the corneal ulcer culture of a patient, later enrolled in the Steroids for Corneal Ulcer Trial (SCUT. To our knowledge this is the first published report from North America of the recovery of C. macginleyi from a serious ocular infection.

  7. Antimicrobial susceptibility of Salmonella enterica strains isolated ...

    African Journals Online (AJOL)

    SARAH

    2015-11-30

    Nov 30, 2015 ... (n=50) and sheep intestine (n=50) were analyzed using standards microbiological method for ... handlers are still observed during food marketing ... was conducted according to ISO 6579: 2002 (E) methods ..... from local beverages (bissap, gnamakoudji) sold ... Salmonella isolated from children under five.

  8. Molecular characterization of Danish Cryptosporidium parvum isolates

    DEFF Research Database (Denmark)

    Enemark, Heidi L.; Ahrens, Peter; Juel, Cynthia Dawn

    2002-01-01

    The genetic polymorphism among 271 Danish Cryptosporidium isolates of human and animal origin was studied by partial amplification and sequencing of the Cryptosporidium oocyst wall protein (COWP) gene, the 18S rDNA, and a microsatellite locus.dagger Furthermore, the microsatellite locus was studi...

  9. on Isolated Smooth Muscle Preparation in Rats

    African Journals Online (AJOL)

    Samuel Olaleye

    ABSTRACT. This study investigated the receptor effects of methanolic root extract of ... Phytochemical Analysis: Photochemistry of the methanolic extract was ... mounted with resting tension 0.5g in an organ bath containing .... Effects of extra cellular free Ca2+ and 0.5mM ... isolated smooth muscle by high K+ on the other.

  10. Isolation of Circulating Tumor Cells by Dielectrophoresis

    Directory of Open Access Journals (Sweden)

    Peter R. C. Gascoyne

    2014-03-01

    Full Text Available Dielectrophoresis (DEP is an electrokinetic method that allows intrinsic dielectric properties of suspended cells to be exploited for discrimination and separation. It has emerged as a promising method for isolating circulation tumor cells (CTCs from blood. DEP-isolation of CTCs is independent of cell surface markers. Furthermore, isolated CTCs are viable and can be maintained in culture, suggesting that DEP methods should be more generally applicable than antibody-based approaches. The aim of this article is to review and synthesize for both oncologists and biomedical engineers interested in CTC isolation the pertinent characteristics of DEP and CTCs. The aim is to promote an understanding of the factors involved in realizing DEP-based instruments having both sufficient discrimination and throughput to allow routine analysis of CTCs in clinical practice. The article brings together: (a the principles of DEP; (b the biological basis for the dielectric differences between CTCs and blood cells; (c why such differences are expected to be present for all types of tumors; and (d instrumentation requirements to process 10 mL blood specimens in less than 1 h to enable routine clinical analysis. The force equilibrium method of dielectrophoretic field-flow fractionation (DEP-FFF is shown to offer higher discrimination and throughput than earlier DEP trapping methods and to be applicable to clinical studies.

  11. Isolation of cowpea genes conferring drought tolerance ...

    African Journals Online (AJOL)

    The main objective of this study was to identify and isolate the genes conferring drought tolerance in cowpea. A cDNA library enriched for cowpea genes expressed specifically during responses to drought was constructed. A procedure called suppression subtractive hybridisation (SSH) was successfully employed to obtain ...

  12. Aminoglycoside resistance among isolates of nosocomial Enterobacteriaceae

    International Nuclear Information System (INIS)

    Botha, P.L.; Elisha, G.; Pratt, K.

    1981-01-01

    Fifty-seven gentamicin-resistant isolates of Enterobacteriaceae, obtained from patients attending hospital, were examined for the production of aminoglycoside-modifying enzymes. Of the 51 strains producing such enzymes, 34 were presumptively plasmid-mediated as indicated by conjugation experiments

  13. SCREENING AND BIOASSAY-GUIDED ISOLATION OF ...

    African Journals Online (AJOL)

    DR. AMINU

    2013-06-01

    Jun 1, 2013 ... Antimicrobial Sensitivity Test (ATS) was adopted in testing the bioactivity of the plant extracts against seven bacteria and ... (LM1-01) of the leaves of the Laggera mollis using column chromatography, led to the isolation of two pure ... exploration of medicinal plants for the treatment of microbial infections of ...

  14. Isolation of Cholesterol from an Egg Yolk

    Science.gov (United States)

    Taber, Douglass F.; Li, Rui; Anson, Cory M.

    2011-01-01

    A simple procedure for the isolation of the cholesterol, by hydrolysis and extraction followed by column chromatography, is described. The cholesterol can be further purified by complexation with oxalic acid. It can also be oxidized and conjugated to cholestenone. The source of the cholesterol is one egg yolk, which contains about 200 mg of…

  15. Genetic homogeneity among Ugandan isolates of Xanthomonas ...

    African Journals Online (AJOL)

    Seven random primers were used because of their ability to amplify reproducible and reliable fingerprints generated between 6 - 12 amplicons each from the Xcm isolates obtained from central core of pseudostems, peduncles, fruit peelings, sap, nectar, insects' bodies and bacterial oozes. Regardless of the source and ...

  16. Characterization of Trypanosoma brucei gambiense stocks isolated ...

    African Journals Online (AJOL)

    Trypanosoma brucei gambiense was isolated twice from each of 23 patients in Côte d'Ivoire. Genetic characterization using RAPD (Random Primed Amplified Polymorphic DNA) showed additional variability within a given isoenzyme profile (zymodeme), confirming that this fingerprinting method has a higher discriminative ...

  17. common bacterial isolates from infected eyes abstract

    African Journals Online (AJOL)

    LIVINGSTON

    to open as a result of the accumulation of exudates during the night. ... Bacteria were isolated most on the eye infections of the conjunctiva 222(66.70%), then the cornea ..... risk after their maternal immunity has disappeared and before their ...

  18. Phylogenomics of Colombian Helicobacter pylori isolates.

    Science.gov (United States)

    Gutiérrez-Escobar, Andrés Julián; Trujillo, Esperanza; Acevedo, Orlando; Bravo, María Mercedes

    2017-01-01

    During the Spanish colonisation of South America, African slaves and Europeans arrived in the continent with their corresponding load of pathogens, including Helicobacter pylori . Colombian strains have been clustered with the hpEurope population and with the hspWestAfrica subpopulation in multilocus sequence typing (MLST) studies. However, ancestry studies have revealed the presence of population components specific to H. pylori in Colombia. The aim of this study was to perform a thorough phylogenomic analysis to describe the evolution of the Colombian urban H. pylori isolates. A total of 115 genomes of H. pylori were sequenced with Illumina technology from H. pylori isolates obtained in Colombia in a region of high risk for gastric cancer. The genomes were assembled, annotated and underwent phylogenomic analysis with 36 reference strains. Additionally, population differentiation analyses were performed for two bacterial genes. The phylogenetic tree revealed clustering of the Colombian strains with hspWestAfrica and hpEurope, along with three clades formed exclusively by Colombian strains, suggesting the presence of independent evolutionary lines for Colombia. Additionally, the nucleotide diversity of horB and vacA genes from Colombian isolates was lower than in the reference strains and showed a significant genetic differentiation supporting the hypothesis of independent clades with recent evolution. The presence of specific lineages suggest the existence of an hspColombia subtype that emerged from a small and relatively isolated ancestral population that accompanied crossbreeding of human population in Colombia.

  19. Probiotic features of two oral Lactobacillus isolates

    Directory of Open Access Journals (Sweden)

    Gordana Zavisic

    2012-03-01

    Full Text Available In this study, we checked lactobacilli strains of human origin for their potential as probiotic. Samples were collected from oral mucosa of 16 healthy individuals, out of which twenty isolates were obtained and two of them were selected and identified as Lactobacillus plantarum (G1 and L. casei (G3. Both isolates exhibited antagonistic action towards pathogenic microorganisms such as Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Salmonella abony, and Clostridium sporogenes, but not on the growth of Candida albicans. The bacteriocin activity against Staphylococcus aureus ATCC 6358-P was shown only by L. plantarum G1. Moreover, the isolates G1 and G3 showed good viability in the acid gastric environment and in the gut environment containing bovine bile salts. The viability of G1 and G3 isolates in the gastrointestinal tract, and the adhesion to the intestinal mucosa were also confirmed in vivo. The biochemical tests of blood samples revealed lower levels of serum triglycerides and cholesterol, as well as reduced activity of alkaline phosphatase in all lactobacilli-treated Wistar rats, compared to control ones. No toxicity for NMRI Ham mice was observed. According to our experimental results, these findings imply that L. plantarum G1 and L. casei G3 could be characterized as potential probiotics.

  20. Probiotic features of two oral Lactobacillus isolates.

    Science.gov (United States)

    Zavisic, Gordana; Petricevic, Sasa; Radulovic, Zeljka; Begovic, Jelena; Golic, Natasa; Topisirovic, Ljubisa; Strahinic, Ivana

    2012-01-01

    In this study, we checked lactobacilli strains of human origin for their potential as probiotic. Samples were collected from oral mucosa of 16 healthy individuals, out of which twenty isolates were obtained and two of them were selected and identified as Lactobacillus plantarum (G1) and L. casei (G3). Both isolates exhibited antagonistic action towards pathogenic microorganisms such as Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Salmonella abony, and Clostridium sporogenes, but not on the growth of Candida albicans. The bacteriocin activity against Staphylococcus aureus ATCC 6358-P was shown only by L. plantarum G1. Moreover, the isolates G1 and G3 showed good viability in the acid gastric environment and in the gut environment containing bovine bile salts. The viability of G1 and G3 isolates in the gastrointestinal tract, and the adhesion to the intestinal mucosa were also confirmed in vivo. The biochemical tests of blood samples revealed lower levels of serum triglycerides and cholesterol, as well as reduced activity of alkaline phosphatase in all lactobacilli-treated Wistar rats, compared to control ones. No toxicity for NMRI Ham mice was observed. According to our experimental results, these findings imply that L. plantarum G1 and L. casei G3 could be characterized as potential probiotics.

  1. Decoherence in Nearly-Isolated Quantum Dots

    DEFF Research Database (Denmark)

    Folk, J.; M. Marcus, C.; Harris jr, J.

    2000-01-01

    Decoherence in nearly-isolated GaAs quantum dots is investigated using the change in average Coulomb blockade peak height upon breaking time-reversal symmetry. The normalized change in average peak height approaches the predicted universal value of 1/4 at temperatures well below the single...

  2. PATHOGENIC POTENTIALS OF ESCHERICHIA COLI ISOLATED ...

    African Journals Online (AJOL)

    Electrolyte and haematological parameters in rabbits infected with pathogenic isolates of Escherichia coli from rural water supplies in Rivers State, Nigeria, where monitored. Rabbits were orally infected with suspension containing 3x107 cfu /ml of Escherichia coli to induce diarrhoea, and the electrolyte (sodium, potassium ...

  3. SINGLE CONVERSION ISOLATED IMPEDANCE TRANSFORMATION AMPLIFIER

    DEFF Research Database (Denmark)

    2003-01-01

    The invention relates to a switch mode power amplifier. A first and a second change-over switch are inserted between a DC voltage supply and a primary side of an isolation transformer. Two secondary windings are connected to a power output terminal. A first and a second secondary side power switc...

  4. Isolated systems with wind power. Main report

    Energy Technology Data Exchange (ETDEWEB)

    Lundsager, P.; Bindner, H.; Clausen, N.E.; Frandsen, S.; Hansen, L.H.; Hansen, J.C.

    2001-06-01

    The overall objective of this research project is to study the development of methods and guidelines rather than 'universal solutions' for the use of wind energy in isolated communities. The main specific objective of the project is to develop and present a more unified and generally applicable approach for assessing the technical and economical feasibility of isolated power supply systems with wind energy. As a part of the project the following tasks were carried out: Review of literature, field measurements in Egypt, development of an inventory of small isolated systems, overview of end-user demands, analysis of findings and development of proposed guidelines. The project is reported in one main report and four topical reports, all of them issued as Risoe reports. This is the Main Report Risoe-R-1256, summing up the activities and findings of the project and outlining an Implementation Strategy for Isolated Systems with Wind Power, applicable for international organisations such as donor agencies and development banks. (au)

  5. Geological problems in radioactive waste isolation

    International Nuclear Information System (INIS)

    Witherspoon, P.A.

    1991-01-01

    The problem of isolating radioactive wastes from the biosphere presents specialists in the fields of earth sciences with some of the most complicated problems they have ever encountered. This is especially true for high level waste (HLW) which must be isolated in the underground and away from the biosphere for thousands of years. Essentially every country that is generating electricity in nuclear power plants is faced with the problem of isolating the radioactive wastes that are produced. The general consensus is that this can be accomplished by selecting an appropriate geologic setting and carefully designing the rock repository. Much new technology is being developed to solve the problems that have been raised and there is a continuing need to publish the results of new developments for the benefit of all concerned. The 28th International Geologic Congress that was held July 9--19, 1989 in Washington, DC provided an opportunity for earth scientists to gather for detailed discussions on these problems. Workshop W3B on the subject, ''Geological Problems in Radioactive Waste Isolation -- A World Wide Review'' was organized by Paul A Witherspoon and Ghislain de Marsily and convened July 15--16, 1989 Reports from 19 countries have been gathered for this publication. Individual papers have been cataloged separately

  6. Isolation of deoxyribonucleic acids (A Review)

    International Nuclear Information System (INIS)

    Garcia Pineda, M. de

    1974-01-01

    The criteria of choice in this Review have been to gather some of the last advances in the methodology of DNAs isolation; also the description of the generally accepted procedures has been emphasized. Only papers published before March 1974 are reviewed, because this work has been finished during this month. (Author) 109 refs

  7. Enumeration, Isolation and Antibiotic Susceptibility Profile of ...

    African Journals Online (AJOL)

    For each mobile phone, two sterile swabs moistened with normal saline were ... antibiotics. MATERIALS AND METHODS ... 28 isolates comprising of four genera of E. coli. 7(25.0%), S. ... personal mobile phones in some locations within Kano ... clothing, food and/or hands of the users (Uabol- .... Journal of Food Protection,.

  8. Social isolation and all-cause mortality

    DEFF Research Database (Denmark)

    Laugesen, Kristina; Baggesen, Lisbeth Munksgård; Schmidt, Sigrún Alba Jóhannesdóttir

    2018-01-01

    and Syme's social network index (SNI), which combines four components of social networks (partnership, interaction with family/friends, religious activities, and membership in organizations/clubs) into an index, ranging from 0/1 (most socially isolated) to 4 (least socially isolated). We estimated.......6% for SNI 0/1 and 3.9% for SNI 4. Adjusted MRRs comparing SNI 0/1 with SNI 4 were 1.7 (95% CI: 1.1-2.6) among men and 1.6 (95% CI: 0.83-2.9) among women. Having no partner was associated with an adjusted MRR of 1.5 (95% CI: 1.2-2.1) for men and 1.7 (95% CI: 1.2-2.4) for women. In conclusion, social......Social isolation is associated with increased mortality. Meta-analytic results, however, indicate heterogeneity in effect sizes. We aimed to provide new evidence to the association between social isolation and mortality by conducting a population-based cohort study. We reconstructed the Berkman...

  9. Isolation of Circulating Tumor Cells by Dielectrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Gascoyne, Peter R. C., E-mail: pgascoyn@mdanderson.org [Department of Imaging Physics Research, The University of Texas M.D. Anderson Cancer Center Unit 951, 1515 Holcombe Boulevard, Houston, TX 77030 (United States); Shim, Sangjo [Department of Imaging Physics Research, The University of Texas M.D. Anderson Cancer Center Unit 951, 1515 Holcombe Boulevard, Houston, TX 77030 (United States); Department of Biomedical Engineering, The University of Texas at Austin, 1 University Station, C0800, Austin, TX 78712 (United States); Present address: Micro & Nanotechnology Laboratory, University of Illinois at Urbana-Champaign, Urbana, 208 North Wright Street, Urbana, IL 61801 (United States)

    2014-03-12

    Dielectrophoresis (DEP) is an electrokinetic method that allows intrinsic dielectric properties of suspended cells to be exploited for discrimination and separation. It has emerged as a promising method for isolating circulation tumor cells (CTCs) from blood. DEP-isolation of CTCs is independent of cell surface markers. Furthermore, isolated CTCs are viable and can be maintained in culture, suggesting that DEP methods should be more generally applicable than antibody-based approaches. The aim of this article is to review and synthesize for both oncologists and biomedical engineers interested in CTC isolation the pertinent characteristics of DEP and CTCs. The aim is to promote an understanding of the factors involved in realizing DEP-based instruments having both sufficient discrimination and throughput to allow routine analysis of CTCs in clinical practice. The article brings together: (a) the principles of DEP; (b) the biological basis for the dielectric differences between CTCs and blood cells; (c) why such differences are expected to be present for all types of tumors; and (d) instrumentation requirements to process 10 mL blood specimens in less than 1 h to enable routine clinical analysis. The force equilibrium method of dielectrophoretic field-flow fractionation (DEP-FFF) is shown to offer higher discrimination and throughput than earlier DEP trapping methods and to be applicable to clinical studies.

  10. A failure detection and isolation system simulator

    International Nuclear Information System (INIS)

    Assumpcao Filho, E.O.; Nakata, H.

    1990-04-01

    A failure detection and isolation system (FDI) simulation program has been developed for IBM-PC microcomputers. The program, based on the sequential likelihood ratio testing method developed by A. Wald, was implemented with the Monte-Carlo technique. The calculated failure detection rate was favorably compared against the wind-tunnel experimental redundant temperature sensors. (author) [pt

  11. Isolated laryngeal myasthenia gravis for 26 years.

    Science.gov (United States)

    Renard, Dimitri; Hedayat, Amir; Gagnard, Corinne

    2015-02-01

    Laryngeal myasthenia gravis is a relatively rare variant of myasthenia gravis. A vast portion of patients with initial laryngeal myasthenia gravis develop involvement of ocular and/or extra-ocular muscles during the years after symptom onset although a minority of laryngeal myasthenia gravis patients continues to have isolated laryngeal muscle involvement for several years. We present a 58-year-old woman with recurrent episodic isolated dysphonia (associated with diffuse bilateral vocal cord paresis on laryngoscopy) since the age of 32. Dysphonia became permanent since 6 months. A diagnosis of laryngeal myasthenia gravis was made based on abnormal single-fiber electromyography and spectacular response to pyridostigmine treatment. Repetitive nerve stimulation was normal and anti-acetylcholine receptor and anti-muscle specific tyrosine kinase antibodies were absent. This case shows that laryngeal myasthenia gravis can be isolated during 26 years of follow-up. We propose that even when myasthenia gravis seems unlikely as underlying mechanism of isolated dysphonia (because of lack of antibodies, normal repetitive nerve stimulation, and absence of extra-laryngeal involvement after years of follow-up), single-fiber electromyography should be performed and myasthenia gravis treatment should be tried. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Isolated pharmacomechanical thrombolysis using the Trellis system

    LENUS (Irish Health Repository)

    O’Sullivan, GJ

    2010-01-01

    While anticoagulation remains the current gold standard for treating acute deep vein thrombosis,1 there is a growing body of evidence that rapid thrombus removal results in better short- and long-term outcomes.2–5 This is a practical guide to achieve rapid thrombus removal with isolated pharmacomechanical thrombolysis using the Trellis® peripheral infusion system.\\r\

  13. An isolated vaginal metastasis from rectal cancer

    Directory of Open Access Journals (Sweden)

    Ai Sadatomo

    2016-02-01

    Conclusion: We should keep the vagina within the field of view of pelvic MRI, which is one of the preoperative diagnostic tools for colorectal cancer. If female patients show gynecological symptoms, gynecological examination should be recommended. Isolated vaginal metastases are an indication for surgical resection, and adjuvant chemotherapy is also recommended.

  14. Isolated macrodactyly or extremely localized Proteus syndrome?

    NARCIS (Netherlands)

    van Bever, Y.; Hennekam, R. C.

    1994-01-01

    We report on a woman with unilateral macrosyndactyly of the second and third toes, a local plantar soft tissue lump, and radiographically an abnormal shape of the phalanges of the affected toes. This finding may represent either an isolated macrosyndactyly or an extremely localised form of Proteus

  15. Isolation and characterization of methanogenic bacteria from ...

    African Journals Online (AJOL)

    Eliud Wafula

    2016-11-23

    Nov 23, 2016 ... concentration of methane for most isolates was recorded at temperatures of 35 and 37°C for all the pH ranges. ... consumption reflects the state of development of a ... and CO2. (Bayer et al., 2004). The environmental and internal factors usually control the ... fermentation samples of the biogas plants are still.

  16. Isolated Fournier's gangrene of the penis.

    Science.gov (United States)

    Obi, A O

    2016-01-01

    To share experience on the presentation and management of 4 cases of isolated penile Fournier's gangrene. Clinical and demographic data of four patients with isolated penile Fournier's gangrene seen over an 8-year period (January 2006-December 2013) were reviewed. All patients had intravenous fluid resuscitation, emergency surgical debridement, and broad-spectrum intravenous antibiotics. Fournier's gangrene of the penis was, respectively, due to long segment anterior urethral stricture, penile edema from poorly controlled congestive cardiac failure, penile abrasion from oral sex and idiopathic. The mean age of the patients was 34.3 ± 5.6 years. One patient with urethral stricture had urinary tract infection. The patients presented with a prodromal period of genital pain and fever followed by genital swelling, gangrene, and ulceration. The most common wound swab isolates were Staphylococcus aureus and Escherichia coli. Only the skin and dartos fascia were affected with sparing of the corporal cylinders. Mean hospital stay was 17.3 ± 3.0 days and mean Fournier's gangrene severity index (FGSI) was 4.0 ± 0.8. Wound closure was achieved by split skin grafting in 2 patients, delayed primary closure in the third and healing by secondary intention in the fourth patient. Subjectively assessed erectile function was preserved in all four patients. Isolated Fournier's gangrene of the penis is very rare. It is associated with low FGSI and sparing of the three corporal cylinders. It may rarely follow oral sexual practice.

  17. Total excitation of the isolated human heart

    NARCIS (Netherlands)

    Durrer, D.; Dam, R.Th. van; Freud, G.E.; Janse, M.J.; Meijler, F.L.; Arzbaecher, R.C.

    To obtain information conceming the time course and instantaneous distribution of the excitatory process of the normal human healt, studies were made on isolated human hearts from seven individuals who died from various cerebral conditions, but who had no history of cardiac disease. Measurements

  18. Isolated posterior fossa involvement of progressive multifocal ...

    African Journals Online (AJOL)

    2017-11-14

    Nov 14, 2017 ... and the HIV pandemic has resulted in an increased prevalence of PML, affecting 3% – 7% of HIV- infected ... majority of HIV-infected patients with PML have CD4 lymphocyte counts < 200 cells/mm3. JC ... infrequent contrast enhancement.3 There is no involvement of the optic nerves or spinal cord. Isolated ...

  19. Polyclonal antibodies of Ganoderma boninense isolated from ...

    African Journals Online (AJOL)

    Polyclonal antibodies of Ganoderma boninense isolated from Malaysian oil palm for detection of basal stem rot disease. ... ELISA-PAb shows better detection as compared to cultural-based method, Ganoderma selective medium (GSM) with an improvement of 18% at nursery trial. The present study also demonstrates ...

  20. Isolation, characterization and molecular weight determination of ...

    African Journals Online (AJOL)

    Shanmugam

    2013-01-30

    Jan 30, 2013 ... an attempt was made to isolate and characterize collagen from the marine sponge, Spirastrella inconstans. The total ... major constituent of many connective tissues. It is distributed in skin, bones, cartilage, tendons, ligaments, blood vessels, teeth ..... sponge fiber skeleton: a biomimetic scaffold for human.

  1. Shewanella strain isolated from black powder

    Energy Technology Data Exchange (ETDEWEB)

    Lutterbach, Marcia T.S.; Contador, Luciana S.; Oliveira, Ana Lucia C.; Galvao, Mariana M. [National Institute of Technology (INT), Rio de Janeiro, RJ (Brazil); Pimenta, Gutemberg S. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2009-07-01

    Black powder is a term frequently used to refer to residues formed by various types of iron sulfides mixed with contaminants eventually present in the natural gas flow. According to some researchers, the occurrence of black powder in gas pipelines, besides its chemical corrosion origin, can be directly related to the sulfate-reducing bacteria (SRB) metabolism in this environment. A black powder sample was inoculated in a Post gate E medium modified with the addition of thioglycolate. The resulting positive culture was kept in the laboratory for four years until its use. A dilution technique was then performed aiming to isolate an SRB strain. The bacterial strain isolated and identified through DNA sequencing was not an SRB but rather a Shewanella sp. Compared to the sulfate-reducing bacteria group-traditionally considered the foremost responsible for microbially-influenced corrosion (MIC) - Shewanella is a facultative anaerobe and has a versatile metabolism. Shewanella is able to reduce ferric iron and sulfite, oxidize hydrogen gas, and produce hydrogen sulfide; therefore, these bacteria can be responsible for MIC and pit formation. The isolated Shewanella was used in a corrosion experiment, and the corrosion products were characterized by X-ray diffraction, identifying iron sulfides, iron oxides, and sulfur. Our results indicate that the strain isolated, S. putrefaciens, plays a key role in corrosion problems in gas pipelines. (author)

  2. Isolation and molecular characterization of phytase producing ...

    African Journals Online (AJOL)

    Isolation and molecular characterization of phytase producing bacteria from Malaysia hot springs. ... The strains were further analyzed in broth culture using sodium phytate as substrate. Among them, strain L3 was selected as the best producer (0.16 U/ml after 72 h of culture). This phytase showed optimal activity at 37 °C ...

  3. Characterization of Proteus mirabilis isolates from broilers

    Science.gov (United States)

    Background: Proteus mirabilis is ubiquitous in the environment and is regarded as a part of the normal flora in human gastrointestinal tract. However, this bacterium is also an opportunistic human pathogen that causes urinary tract infections. Recently, this microorganism has been isolated from m...

  4. Profound improvements of isolated microspores culture techniques ...

    African Journals Online (AJOL)

    We studied the effects of sampling stages, physical conditions (like temperature), culture conditions, embryo long-distance transportation methodology and plantlet regeneration on isolated microspores from donor plants in field. Results indicated that if microspores were sampled in bud stage instead of blooming stage to ...

  5. Isolation of a mycoplasma from sarcoid tissue.

    Science.gov (United States)

    Jansson, E; Hannuksela, M; Eklund, H; Halme, H; Tuuri, S

    1972-10-01

    Using a modified cell-free culture medium, a mycoplasma was isolated from sarcoid lymph nodes in two cases and from sarcoid skin lesions in four out of seven cases of chronic sarcoidosis. Growth inhibition tests showed that the isolates were related to Mycoplasma orale type 1. By the indirect haemagglutination method, 244 cases of definite or probable sarcoidosis, 160 patients with other diseases, and 355 blood donors were tested for antibodies against an isolated mycoplasma (strain 215-M). Titres [unk] 16 were found in 14% of the patients with sarcoidosis and in 8% of the patients with other diseases but only in 0.6% of the blood donors. The proportion of patients with high antibody titres among those with sarcoidosis and erythema nodosum was smaller (8%) than among those with other forms of sarcoidosis (17%). The role of the mycoplasmas isolated from sarcoid tissues remains obscure, but it is possible that these organisms are only an expression of altered immunity in sarcoidosis.

  6. Isolation of Circulating Tumor Cells by Dielectrophoresis

    International Nuclear Information System (INIS)

    Gascoyne, Peter R. C.; Shim, Sangjo

    2014-01-01

    Dielectrophoresis (DEP) is an electrokinetic method that allows intrinsic dielectric properties of suspended cells to be exploited for discrimination and separation. It has emerged as a promising method for isolating circulation tumor cells (CTCs) from blood. DEP-isolation of CTCs is independent of cell surface markers. Furthermore, isolated CTCs are viable and can be maintained in culture, suggesting that DEP methods should be more generally applicable than antibody-based approaches. The aim of this article is to review and synthesize for both oncologists and biomedical engineers interested in CTC isolation the pertinent characteristics of DEP and CTCs. The aim is to promote an understanding of the factors involved in realizing DEP-based instruments having both sufficient discrimination and throughput to allow routine analysis of CTCs in clinical practice. The article brings together: (a) the principles of DEP; (b) the biological basis for the dielectric differences between CTCs and blood cells; (c) why such differences are expected to be present for all types of tumors; and (d) instrumentation requirements to process 10 mL blood specimens in less than 1 h to enable routine clinical analysis. The force equilibrium method of dielectrophoretic field-flow fractionation (DEP-FFF) is shown to offer higher discrimination and throughput than earlier DEP trapping methods and to be applicable to clinical studies

  7. Isolation and Characterization of Efficient Phosphate Solubilizing ...

    African Journals Online (AJOL)

    Vostro154032bit

    Research Article http://dx.doi.org/10.4314/mejs.v9i2.9. Momona Ethiopian Journal of Science (MEJS), V9(2):262-273,2017 ©CNCS, Mekelle University, ISSN:2220-184X. Isolation and Characterization of Efficient Phosphate Solubilizing Bacillus (PSB) from Different Agro-ecological Zones of Tigray Soil, Ethiopia. Kibrom, F.G.

  8. Geological problems in radioactive waste isolation

    Energy Technology Data Exchange (ETDEWEB)

    Witherspoon, P.A. (ed.)

    1991-01-01

    The problem of isolating radioactive wastes from the biosphere presents specialists in the fields of earth sciences with some of the most complicated problems they have ever encountered. This is especially true for high level waste (HLW) which must be isolated in the underground and away from the biosphere for thousands of years. Essentially every country that is generating electricity in nuclear power plants is faced with the problem of isolating the radioactive wastes that are produced. The general consensus is that this can be accomplished by selecting an appropriate geologic setting and carefully designing the rock repository. Much new technology is being developed to solve the problems that have been raised and there is a continuing need to publish the results of new developments for the benefit of all concerned. The 28th International Geologic Congress that was held July 9--19, 1989 in Washington, DC provided an opportunity for earth scientists to gather for detailed discussions on these problems. Workshop W3B on the subject, Geological Problems in Radioactive Waste Isolation -- A World Wide Review'' was organized by Paul A Witherspoon and Ghislain de Marsily and convened July 15--16, 1989 Reports from 19 countries have been gathered for this publication. Individual papers have been cataloged separately.

  9. Microbially-Enhanced Redox Solution Reoxidation for Sour Natural Gas Sweetening

    Energy Technology Data Exchange (ETDEWEB)

    Kenneth Brezinsky

    2008-01-15

    The specific objective of this project are to advance the technology and improve the economics of the commercial iron-based chelate processes such as LO-CAT II and SulFerox process utilizing biologically enhanced reoxidation of the redox solutions used in these processes. The project is based on the use of chelated ferric iron as the catalyst for the production of elemental sulfur, and then oxidizing bacteria, such as Thiobacillus Ferrooxidans (ATCC 23270) as an oxidizer. The regeneration of Fe{sup 3+} - chelate is accomplished by the use of these same microbes under mild conditions at 25-30 C and at atmospheric pressure to minimize the chelate degradation process. The pH of the redox solution was observed to be a key process parameter. Other parameters such as temperature, total iron concentration, gas to liquid ratio and bacterial cell densities also influence the overall process. The second part of this project includes experimental data and a kinetic model of microbial H{sub 2}S removal from sour natural gas using thiobacillus species. In the experimental part, a series of experiments were conducted with a commercial chelated iron catalyst at pH ranges from 8.7 to 9.2 using a total iron concentration range from 925 ppm to 1050 ppm in the solution. Regeneration of the solution was carried out by passing air through the solution. Iron oxidizing bacteria were used at cell densities of 2.3 x 10{sup 7}cells/ml for optimum effective performance. In the modeling part, oxidation of Fe{sup 2+} ions by the iron oxidizing bacteria - Thiobacillus Ferrooxidans was studied for application to a continuous stirred tank reactor (CSTR). The factors that can directly affect the oxidation rate such as dilution rate, temperature, and pH were analyzed. The growth of the microorganism was assumed to follow Monod type of growth kinetics. Dilution rate had influence on the rate of oxidation of ferrous iron. Higher dilution rates caused washout of the biomass. The oxidation rate was

  10. Isolation & characterization of Brucella melitensis isolated from patients suspected for human brucellosis in India

    Science.gov (United States)

    Barua, Anita; Kumar, Ashu; Thavaselvam, Duraipandian; Mangalgi, Smita; Prakash, Archana; Tiwari, Sapana; Arora, Sonia; Sathyaseelan, Kannusamy

    2016-01-01

    Background & objectives: Brucellosis is endemic in the southern part of India. A combination of biochemical, serological and molecular methods is required for identification and biotyping of Brucella. The present study describes the isolation and biochemical, molecular characterization of Brucella melitensis from patients suspected for human brucellosis. Methods: The blood samples were collected from febrile patients suspected to have brucellosis. A total of 18 isolates were obtained from 102 blood samples subjected to culture. The characterization of these 18 isolates was done by growth on Brucella specific medium, biochemical reactions, CO2 requirement, H2S production, agglutination with A and M mono-specific antiserum, dye sensitivity to basic fuchsin and thionin. Further, molecular characterization of the isolates was done by amplification of B. melitensis species specific IS711 repetitive DNA fragment and 16S (rRNA) sequence analysis. PCR-restriction fragment length polymorphism (RFLP) analysis of omp2 locus and IS711 gene was also done for molecular characterization. Results: All 102 suspected samples were subjected to bacteria isolation and of these, 18 isolates could be recovered on blood culture. The biochemical, PCR and PCR-RFLP and 16s rRNA sequencing revealed that all isolates were of B. melitensis and matched exactly with reference strain B. melitensis 16M. Interpretation & conclusions: The present study showed an overall isolation rate of 17.64 per cent for B. melitensis. There is a need to establish facilities for isolation and characterization of Brucella species for effective clinical management of the disease among patients as well as surveillance and control of infection in domestic animals. Further studies are needed from different geographical areas of the country with different level of endemicity to plan and execute control strategies against human brucellosis. PMID:27488010

  11. Teaching basic lung isolation skills on human anatomy simulator: attainment and retention of lung isolation skills.

    Science.gov (United States)

    Latif, Rana K; VanHorne, Edgar M; Kandadai, Sunitha Kanchi; Bautista, Alexander F; Neamtu, Aurel; Wadhwa, Anupama; Carter, Mary B; Ziegler, Craig H; Memon, Mohammed Faisal; Akça, Ozan

    2016-01-20

    Lung isolation skills, such as correct insertion of double lumen endobronchial tube and bronchial blocker, are essential in anesthesia training; however, how to teach novices these skills is underexplored. Our aims were to determine (1) if novices can be trained to a basic proficiency level of lung isolation skills, (2) whether video-didactic and simulation-based trainings are comparable in teaching lung isolation basic skills, and (3) whether novice learners' lung isolation skills decay over time without practice. First, five board certified anesthesiologist with experience of more than 100 successful lung isolations were tested on Human Airway Anatomy Simulator (HAAS) to establish Expert proficiency skill level. Thirty senior medical students, who were naive to bronchoscopy and lung isolation techniques (Novice) were randomized to video-didactic and simulation-based trainings to learn lung isolation skills. Before and after training, Novices' performances were scored for correct placement using pass/fail scoring and a 5-point Global Rating Scale (GRS); and time of insertion was recorded. Fourteen novices were retested 2 months later to assess skill decay. Experts' and novices' double lumen endobronchial tube and bronchial blocker passing rates showed similar success rates after training (P >0.99). There were no differences between the video-didactic and simulation-based methods. Novices' time of insertion decayed within 2 months without practice. Novices could be trained to basic skill proficiency level of lung isolation. Video-didactic and simulation-based methods we utilized were found equally successful in training novices for lung isolation skills. Acquired skills partially decayed without practice.

  12. Numerical activities on seismic isolation in Italy

    International Nuclear Information System (INIS)

    Bettinali, F.; Martelli, A.; Bonacina, G.; Olivieri, M.

    1992-01-01

    The numerical activities which are in progress in Italy in the framework of the seismic isolation studies mainly concern the definition of models for bearings and isolated structures, and their use for test design and the analysis of experimental results. Simple bearing models have been set up, and the development of finite-element (f.e.) three-dimensional (3D) and 2D axisymmetric models is in progress. simple models have been based on the results of single bearing tests: models formed by a spring in parallel to a viscous damper, where both horizontal stiffness and viscous damping vary with displacements, have been developed by ENEA. Models based on hysteretic damping have also been developed by DISP and ISMES. Detailed bearing models include separate elements for the rubber and steel plates. A 3D model has been implemented by ENEA in the ABAQUS code. Linear elastic calculations have been performed with this model. The implementation of an elastic-plastic model for steel is also being completed, together with that of a hyper elastic model of the rubber, based on tests on specimens. Detailed models will be validated based on measured data. They will be used for bearing design and analysis of the effects of defects: some bearings with artificial defects have been fabricated to this purpose. As to the isolated structures, finite-difference programs were set up for the analysis of such structures in the case that they can be represented by sets of one-degree-of-freedom oscillators. The program ISOLA includes the aforementioned simple bearing model of ENEA, where both stiffness and damping depend on displacement and the effects of viscous creep are accounted for. A similar program has been based on the bearing model developed at ISMES. These models have been successfully used to analyse the experimental results concerning both isolated structure mock-ups and actual isolated buildings, based on the single bearing test data for both horizontal stiffness and damping (see a

  13. Klebsiella pneumoniae KPC: first isolations in Italy

    Directory of Open Access Journals (Sweden)

    Carla Fontana

    2009-12-01

    Full Text Available Klebsiella pneumoniae carbapenemase (KPC was detected in two isolates of carbapenem-resistant K. pneumoniae in an italian teaching hospital. This is the first report of a KPC-producing isolates in our country. The first strain was isolated from a urine sample collected from a indwelling urinary catheter in a ICU-patient with subdural haematoma, while the second was from the culture of the central venous catheter (CVC in a patient affected by Crohn’s disease admitted in gastroenterology ward. Both were resistant to all ß-lactams, susceptible to imipenem and meropenem and resistant to ertapenem.They were resistant to other classes of non-ß-lactams antibiotics such as quinolones, aminoglycosides (with the exception of amikacin, trimethoprim-sulfamethoxazole (TMP-SMX as well as to nitrofurantoin.The isolates were not associated with travel abroad.They were found to contain the plasmid encoded carbapenemase gene blaKPC and were also positive to the Hodge’s test.The detection of KPC-producing bacteria has important implications in infection control and public health. The K. pneumoniae carbapenemase (KPC belong to class A ß-lactamases of the functional group 2f. Reported for the first time in U.S. in 2001, these agents were subsequently identified in Europe. KPC strains are typically resistant to penicillins, extended-spectrum cephalosporin and aztreonam and present a peculiar behavior against carbapenems in that MIC is close to the susceptibility value or is borderline (except for ertapenem.This pattern is often associated with resistance to quinolones.The information is conveyed by the resistance plasmids, thus explaining their diffusion and implication in outbreaks of KPC. Despite this, to date there are few reports concerning the isolation of this phenotype in Italy.The purpose of this paper is to present two clinical cases related to the isolation of KPC in our hospital. The KPC-producing strains have been respectively isolated: the first

  14. Methanogenic archaea isolated from Taiwan's Chelungpu fault.

    Science.gov (United States)

    Wu, Sue-Yao; Lai, Mei-Chin

    2011-02-01

    Terrestrial rocks, petroleum reservoirs, faults, coal seams, and subseafloor gas hydrates contain an abundance of diverse methanoarchaea. However, reports on the isolation, purification, and characterization of methanoarchaea in the subsurface environment are rare. Currently, no studies investigating methanoarchaea within fault environments exist. In this report, we succeeded in obtaining two new methanogen isolates, St545Mb(T) of newly proposed species Methanolobus chelungpuianus and Methanobacterium palustre FG694aF, from the Chelungpu fault, which is the fault that caused a devastating earthquake in central Taiwan in 1999. Strain FG694aF was isolated from a fault gouge sample obtained at 694 m below land surface (mbls) and is an autotrophic, mesophilic, nonmotile, thin, filamentous-rod-shaped organism capable of using H(2)-CO(2) and formate as substrates for methanogenesis. The morphological, biochemical, and physiological characteristics and 16S rRNA gene sequence analysis revealed that this isolate belongs to Methanobacterium palustre. The mesophilic strain St545Mb(T), isolated from a sandstone sample at 545 mbls, is a nonmotile, irregular, coccoid organism that uses methanol and trimethylamine as substrates for methanogenesis. The 16S rRNA gene sequence of strain St545Mb(T) was 99.0% similar to that of Methanolobus psychrophilus strain R15 and was 96 to 97.5% similar to the those of other Methanolobus species. However, the optimal growth temperature and total cell protein profile of strain St545Mb(T) were different from those of M. psychrophilus strain R15, and whole-genome DNA-DNA hybridization revealed less than 20% relatedness between these two strains. On the basis of these observations, we propose that strain St545Mb(T) (DSM 19953(T); BCRC AR10030; JCM 15159) be named Methanolobus chelungpuianus sp. nov. Moreover, the environmental DNA database survey indicates that both Methanolobus chelungpuianus and Methanobacterium palustre are widespread in the

  15. Notochord isolation using laser capture microdissection.

    Science.gov (United States)

    Santegoeds, R G C; Yakkioui, Y; Jahanshahi, A; Raven, G; Van Overbeeke, J J; Herrler, A; Temel, Y

    2017-03-01

    Chordoma are malignant tumors of the axial skeleton, which arise from remnants of the notochord. The Notochord (chorda dorsalis) is an essential embryonic structure involved in the development of the nervous system and axial skeleton. Therefore, the notochord seems to be the most biologically relevant control tissue to study chordoma in molecular biology research. Nevertheless, up to now mainly different tissues but not the notochord have been used as control for chordoma, due to difficulty of isolating notochordal tissue. Here, we describe a fast and precise method of isolating notochordal cells. Examination of human fetuses, with a gestation of 9, 11 and 13 weeks, using (immuno)histochemical methods was performed. To isolate pure notochord cells for further molecular biology investigation five flash frozen fetuses between 9 and 10 weeks of gestation were dissected by microtome slicing. Thereafter pure notochord cells for further molecular biology investigation where harvested by using laser capture microdissection (LCM). RNA was extracted from these samples and used in quantitative PCR. This study illustrates notochord of embryonic spines in three different stages of gestation (9-11-13 weeks). Immunohistochemical staining with brachyury showed strong staining of the notochord, but also weak staining of the intervertebral disc and vertebral body. LCM of notochord slices and subsequent total RNA extraction resulted in a good yield of total RNA. qPCR analysis of two housekeeping genes confirmed the quality of the RNA. LCM is a fast and precise method to isolate notochord and the quality and yield RNA extracted from this tissue is sufficient for qPCR analysis. Therefore early embryo notochord isolated by LCM is suggested to be the gold standard for future research in chordoma development, classification and diagnosis. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Isolation of Pasteurella multocida subspec. Multocida from chronic periapical lesion: First isolation in ex-Yugoslavia

    Directory of Open Access Journals (Sweden)

    Suvajdžić Ljiljana Ð.

    2006-01-01

    Full Text Available This study presents five isolates of Pasteurella multocida subsp. multo-cida isolated from chronic periapical inflammatory lesion. We described the methods of sampling and cultivation as well as diagnostic criteria. Pasteurella multocida was diagnosed on the basis of characteristic cultural and tinctorial properties and the facts that all strains produced indole and induced ornithine decarboxilation, glucose, saccharose and manitole fermentation. Isolates produced neither urease, nor fermented lactose and maltose. Further classification to subspecies multocida was based on the fact that all investigated isolates fermented trechalose, xylose and sorbitol the traits which are diagnostically significant for the species. Patients deny any contact with farm animals or pets, which indicates a possible aerosol transport and animal-human as well as human-human infection. We consider that this organism should be paid more attention by dentist, oral surgeons and microbiologists.

  17. Frequency of isolation and antibiotic resistance patterns of bacterial isolates from wound infections

    Directory of Open Access Journals (Sweden)

    Stojanović-Radić, Z.

    2016-12-01

    Full Text Available Six hundred and thirteen bacterial strains were isolated from wound swabs and the isolates were identified on the basis of growth on differential and selective media. In order to test the sensitivity of isolated strains to different antibiotics, the disc diffusion method, according to EUCAST protocol v 5.0 was used. The most common species isolated from wound swabs was Staphylococcus epidermidis (18.4%, followed by Staphylococcus aureus, Pseudomonas aeruginosa and Enterococcus faecalis (16.8%, 12.7% and 10.4%, respectively. The maximum resistance of Gram-positive cocci was observed to penicillin and the lowest to linezolid. Gram-negative bacteria showed the highest resistance to tetracyclines, while the same strains demonstrated the highest sensitivity to polypeptide antibiotics. Comparison of the resistance patterns of Gramnegative and Gram-positive bacterial strains showed significant difference in the tetracycline efficiency.

  18. Isolation & characterization of Brucella melitensis isolated from patients suspected for human brucellosis in India

    Directory of Open Access Journals (Sweden)

    Anita Barua

    2016-01-01

    Interpretation & conclusions: The present study showed an overall isolation rate of 17.64 per cent for B. melitensis. There is a need to establish facilities for isolation and characterization of Brucella species for effective clinical management of the disease among patients as well as surveillance and control of infection in domestic animals. Further studies are needed from different geographical areas of the country with different level of endemicity to plan and execute control strategies against human brucellosis.

  19. The Effectiveness of Seismic Isolation System for Nuclear Equipment

    International Nuclear Information System (INIS)

    Kim, Min-Kyu; Choun, Young-Sun; Seo, Jeong-Moon

    2005-04-01

    In this study, the Emergency Diesel Generator and Off-site Transformer were selected for isolation. For the selection of the most suitable base isolation system, the literature review and the numerical analysis were performed. For the decision of the parameter of isolation system, the sensitivity analysis was performed. Finally the conceptual design of each equipment was performed. In case of EDG, the Coil Spring and Viscous Damper system was selected for isolation system and 45% isolation effect was determined. For the OST, the FPS was selected and 69% isolation effect was determined

  20. The Effectiveness of Seismic Isolation System for Nuclear Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min-Kyu; Choun, Young-Sun; Seo, Jeong-Moon

    2005-04-15

    In this study, the Emergency Diesel Generator and Off-site Transformer were selected for isolation. For the selection of the most suitable base isolation system, the literature review and the numerical analysis were performed. For the decision of the parameter of isolation system, the sensitivity analysis was performed. Finally the conceptual design of each equipment was performed. In case of EDG, the Coil Spring and Viscous Damper system was selected for isolation system and 45% isolation effect was determined. For the OST, the FPS was selected and 69% isolation effect was determined.

  1. Development of analysis methods for seismically isolated nuclear structures

    International Nuclear Information System (INIS)

    Yoo, Bong; Lee, Jae-Han; Koo, Gyeng-Hoi

    2002-01-01

    KAERI's contributions to the project entitled Development of Analysis Methods for Seismically Isolated Nuclear Structures under IAEA CRP of the intercomparison of analysis methods for predicting the behaviour of seismically isolated nuclear structures during 1996-1999 in effort to develop the numerical analysis methods and to compare the analysis results with the benchmark test results of seismic isolation bearings and isolated nuclear structures provided by participating countries are briefly described. Certain progress in the analysis procedures for isolation bearings and isolated nuclear structures has been made throughout the IAEA CRPs and the analysis methods developed can be improved for future nuclear facility applications. (author)

  2. Isolation, Identification, and Evaluation of Novel Probiotic Strains Isolated from Feces of Breast-Fed Infants.

    Science.gov (United States)

    Panya, Marutpong; Lulitanond, Viraphong; Rattanachaikunsopon, Pongsak; Srivoramas, Thanyakarn; Chaiwong, Tarinee

    2016-01-01

    To isolate, identify, and evaluate the probiotic properties of lactic acid bacteria (LAB) isolated from the feces of breast-fed infants. The probiotic tests included investigation of hemolysis activity, survival in simulated gastrointestinal tract conditions (acid and bile salt tolerance), susceptibility to antibiotics, and ability to inhibit selected bacterial pathogens (Escherichia coli O157:H7, Vibrio cholerae and Salmonella enterica subsp enterica serovar Typhimurium). The bacterial species identification was performed by both carbohydrate utilization and partial 16S ribosomal RNA sequencing. Five of fifty LAB isolates (UBU-03, UBU-06, UBU-09, UBU-34, and UBU-37) showed good probiotic properties. These five isolates showed non-hemolysis type (gamma-hemolysis), susceptibility to all antibiotics tested except for vancomycin, ability to survive in the simulated gastrointestinal conditions of both acid and bile salt solution, and ability to inhibit growth of E. coli O157: H7 and V. cholerae. Bacterial species identification revealed that all five isolates were firmly identified as Lactobacillus rhamnosus species. The L. rhamnosus strains that were isolated and characterized in this study could be considered as probiotic strains, and then used for further probiotic characterization in human cell cultures or animal models.

  3. Isolation and screening of azo dye decolorizing bacterial isolates from dye-contaminated textile wastewater

    Directory of Open Access Journals (Sweden)

    Shahid Mahmood

    2011-04-01

    Full Text Available Azo dyes are released into wastewater streams without any pretreatment and pollute water and soilenvironments. To prevent contamination of our vulnerable resources, removal of these dye pollutants is of greatimportance. For this purpose, wastewater samples were collected from dye-contaminated sites of Faisalabad. About200 bacterial isolates were isolated through enrichment and then tested for their potential to remove RemazolBlack-B azo dye in liquid medium. Five bacterial isolates capable of degrading Remazol Black-B azo dye efficientlywere screened through experimentation on modified mineral salt medium. Isolate SS1 (collected from wastewater ofSupreme Textile Industry was able to completely remove the Remazol Black-B dye from the liquid medium in 18 h.Further, the isolate showed the best performance at the dye concentration of 100 mg L-1 medium (pH 7 and attemperature 35oC. Similarly, yeast extract proved to be the best carbon source for decolorization purpose. Theresults imply that the isolate SS1 could be used for the removal of the reactive dyes from textile effluents.

  4. Bacterial consortium for copper extraction from sulphide ore consisting mainly of chalcopyrite

    Directory of Open Access Journals (Sweden)

    E. Romo

    2013-01-01

    Full Text Available The mining industry is looking forward for bacterial consortia for economic extraction of copper from low-grade ores. The main objective was to determine an optimal bacterial consortium from several bacterial strains to obtain copper from the leach of chalcopyrite. The major native bacterial species involved in the bioleaching of sulphide ore (Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, Leptospirillum ferrooxidans and Leptospirillum ferriphilum were isolated and the assays were performed with individual bacteria and in combination with At. thiooxidans. In conclusion, it was found that the consortium integrated by At. ferrooxidans and At. thiooxidans removed 70% of copper in 35 days from the selected ore, showing significant differences with the other consortia, which removed only 35% of copper in 35 days. To validate the assays was done an escalation in columns, where the bacterial consortium achieved a higher percentage of copper extraction regarding to control.

  5. Comparison of camelpox viruses isolated in Dubai.

    Science.gov (United States)

    Pfeffer, M; Meyer, H; Wernery, U; Kaaden, O R

    1996-03-01

    Between October 1993 and March 1994, outbreaks of pox-like exanthemas were observed in several camel raising farms in Dubai. Scabs from twenty camels with either local or generalized lesions were examined, seven of them had previously been vaccinated with a modified live camelpox virus vaccine. Inspection of scabs by electron microscopy confirmed an infection with orthopox viruses (OPV) in 10 animals and with parapox virus in one camel. Investigation of the scabs by polymerase chain reaction and dot blot assay revealed the presence of OPV in 15 or 13 samples, respectively. OPV could be isolated in cell culture in 14 cases. Restriction enzyme profiles characterized all isolates as camelpox virus. Their DNA patterns were virtually identical displaying only slight variations in the terminal fragments. In contrast, the vaccine strain showed a distinct restriction enzyme profile, indicating that it was not involved in the infections.

  6. Incidental Finding of Isolated Colonic Neurofibroma

    Directory of Open Access Journals (Sweden)

    Haritha Chelimilla

    2013-09-01

    Full Text Available Neurofibromatosis is a genetic disorder manifested by characteristic cutaneous lesions called neurofibromas. There are two distinct neurocutaneous syndromes named neurofibromatosis type 1 (also called von Recklinghausen disease or NF1 and neurofibromatosis type 2 (NF2. NF1 is by far the most common presentation and is caused by an autosomal dominant mutation in the NF1 gene mapped to chromosome 17q11.2. The literature shows that gastrointestinal involvement is noted in systemic neurofibromatosis in up to 25% of patients, but isolated intestinal neurofibromatosis is a very rare manifestation. We herein present the case of a 70-year-old woman who was diagnosed with an isolated colonic neurofibroma without any systemic signs of neurofibromatosis; only a few case reports of this condition have been published to date.

  7. Actinomyces Species Isolated from Breast Infections

    Science.gov (United States)

    Loh, S. F.; Morris, T.; Hughes, H.; Dixon, J. M.

    2015-01-01

    Actinomycosis is a chronic infection caused by Actinomyces species characterized by abscess formation, tissue fibrosis, and draining sinuses. The spectrum of infections caused by Actinomyces species ranges from classical invasive actinomycosis to a less invasive form of superficial skin and soft tissue infection. We present a review detailing all Actinomyces species isolated from breast infections in NHS Lothian between 2005 and 2013, Actinomyces species isolated from breast infections referred to the United Kingdom Anaerobe Reference Unit between 1988 and 2014, and cases describing Actinomyces breast infections published in the medical literature since 1994. Actinomyces species are fastidious organisms which can be difficult to identify and are likely to be underascertained as a cause of breast infections. Due to improved diagnostic methods, they are increasingly associated with chronic, recurrent breast infections and may play a more significant role in these infections than has previously been appreciated. PMID:26224846

  8. Biodiversity of Bacteria Isolated from Different Soils

    Directory of Open Access Journals (Sweden)

    Fatma YAMAN

    2017-01-01

    Full Text Available The aim of this study was to determine the biodiversity of PHB producing bacteria isolated from soils where fruit and vegetable are cultivated (onion, grape, olive, mulberry and plum in Aydın providence. Morphological, cultural, biochemical, and molecular methods were used for bacteria identification. These isolated bacteria were identified by 16S rRNA sequencing and using BLAST. The following bacteria Bacillus thuringiensis (6, Bacillus cereus (8, Bacillus anthrachis (1, Bacillus circulans (1, Bacillus weihenstephanensis (1, Pseudomonas putida (1, Azotobacter chroococcum (1, Brevibacterium frigoritolerans (1, Burkholderia sp. (1, Staphylococcus epidermidis (1, Streptomyces exfoliatus (1, Variovorax paradoxus (1 were found. The Maximum Likelihood method was used to produce a molecular phylogenetic analysis and a phylogenetic tree was constructed. These bacteria can produce polyhydroxybutyrate (PHB which is an organic polymer with commercial potential as a biodegradable thermoplastic. PHB can be used instead of petrol derivated non-degradable plastics. For this reason, PHB producing microorganisms are substantial in industry.

  9. Waste isolation facility description: bedded salt

    Energy Technology Data Exchange (ETDEWEB)

    1976-09-01

    The waste isolation facility is designed to receive and store three basic types of solidified wastes: high-level wastes, intermediate level high-gamma transuranic waste, and low-gamma transuranic wastes. The facility under consideration in this report is designed for bedded salt at a depth of approximately 1800 ft. The present design for the facility includes an area which would be used initially as a pilot facility to test the viability of the concept, and a larger facility which would constitute the final storage area. The total storage area in the pilot facility is planned to be 77 acres and in the fuel facility 1601 acres. Other areas for shaft operations and access would raise the overall size of the total facility to slightly less than 2,000 acres. The following subjects are discussed in detail: surface facilities, shaft design and characteristics, design and construction of the underground waste isolation facility, ventilation systems, and design requirements and criteria. (LK)

  10. Antioxidant activity directed isolations form punica granatum

    International Nuclear Information System (INIS)

    Siddiqi, R.; Saeed, M.G.; Sayeed, S.A.

    2012-01-01

    The extracts derived from pomegranate juice following antioxidant activity directed isolation were screened for their antioxidant activity through their ability to scavenge 2,2- diphenyl-l-picrylhydrazyl (DPPH) radicals. Only fractions which exhibited >50 / 0 DPPH scavenging effect at each step of isolation were selected for further purification and their ability to reduce peroxide formation (peroxide value) in heated com oil. Phytochemical analysis of the pure compounds finally obtained, revealed the presence of pelargonidin-3- galactose (Pg-3-galactose), cyanidin-3-glucose (Cy-3-Glucose), gallic acid, quercetin and myricetin in the fractions exhibiting >50% DPPH scavenging potential. The order of antioxidant activity of these pure compounds by DPPH method was found to be gallic acid> quercetin> myricetin> Cy-3-galactose> Pg-3-Glucose while order with respect to reduction in peroxide value (PV) was the reverse of DPPH. (author)

  11. Waste isolation facility description: bedded salt

    International Nuclear Information System (INIS)

    1976-09-01

    The waste isolation facility is designed to receive and store three basic types of solidified wastes: high-level wastes, intermediate level high-gamma transuranic waste, and low-gamma transuranic wastes. The facility under consideration in this report is designed for bedded salt at a depth of approximately 1800 ft. The present design for the facility includes an area which would be used initially as a pilot facility to test the viability of the concept, and a larger facility which would constitute the final storage area. The total storage area in the pilot facility is planned to be 77 acres and in the fuel facility 1601 acres. Other areas for shaft operations and access would raise the overall size of the total facility to slightly less than 2,000 acres. The following subjects are discussed in detail: surface facilities, shaft design and characteristics, design and construction of the underground waste isolation facility, ventilation systems, and design requirements and criteria

  12. Isolation of Human Innate Lymphoid Cells.

    Science.gov (United States)

    Krabbendam, Lisette; Nagasawa, Maho; Spits, Hergen; Bal, Suzanne M

    2018-06-29

    Innate lymphoid cells (ILCs) are innate immune cells of lymphoid origin that have important effector and regulatory functions in the first line of defense against pathogens, but also regulate tissue homeostasis, remodeling, and repair. Their function mirrors T helper cells and cytotoxic CD8 + T lymphocytes, but they lack expression of rearranged antigen-specific receptors. Distinct ILC subsets are classified in group 1 ILCs (ILC1s), group 2 ILCs (ILC2s), and group 3 ILCs (ILC3s and lymphoid tissue-inducer cells), based on the expression of transcription factors and the cytokines they produce. As the frequency of ILCs is low, their isolation requires extensive depletion of other cell types. The lack of unique cell surface antigens further complicates the identification of these cells. Here, methods for ILC isolation and characterization from human peripheral blood and different tissues are described. © 2018 by John Wiley & Sons, Inc. © 2018 John Wiley & Sons, Inc.

  13. Adaptive vibration isolation system for diesel engine

    Institute of Scientific and Technical Information of China (English)

    YANG Tie-jun; ZHANG Xin-yu; XIAO You-hong; HUANG Jin-e; LIU Zhi-gang

    2004-01-01

    An active two-stage isolation mounting, on which servo-hydraulic system is used as the actuator (secondary vibration source) and a diesel engine is used as primary vibration source, has been built. The upper mass of the mounting is composed of a 495diesel and an electrical eddy current dynamometer. The lower mass is divided into four small masses to which servo-hydraulic actuator and rubber isolators are attached. According to the periodical characteristics of diesel vibration signals, a multi-point adaptive strategy based on adaptive comb filtered algorithm is applied to active multi-direction coupled vibrations control for the engine. The experimental results demonstrate that a good suppression in the effective range of phase compensation in secondary path (within 100Hz) at different operation conditions is achieved, and verify that this strategy is effective. The features of the active system, the development activities carried out on the system and experimental results are discussed in the paper.

  14. Characterization of Italian isolates of Inonotus rickii

    Directory of Open Access Journals (Sweden)

    Tiziana ANNESI

    2011-01-01

    Full Text Available Thirty-seven isolates of Inonotus rickii, a pathogenic fungus causing white rot and cankers, were collected from diseased boxelder trees lining boulevards in Rome and from other hosts in Rome and Sicily. During the survey, it was observed that this fungus occasionally produced basidiomes, but more frequently it had anamorphic structures that released a brown powdery mass of chlamydospores, presumably acting as asexual propagules. All isolates were characterized using random amplified microsatellite analysis and somatic incompatibility tests in order to investigate the diversity of genotypes within and between the different disease centers surveyed in Italy. The results suggest that both sexual and asexual reproduction play an important role in the spread of this disease, with important epidemiological implications. .

  15. Highly Dense Isolated Metal Atom Catalytic Sites

    DEFF Research Database (Denmark)

    Chen, Yaxin; Kasama, Takeshi; Huang, Zhiwei

    2015-01-01

    -ray diffraction. A combination of electron microscopy images with X-ray absorption spectra demonstrated that the silver atoms were anchored on five-fold oxygen-terminated cavities on the surface of the support to form highly dense isolated metal active sites, leading to excellent reactivity in catalytic oxidation......Atomically dispersed noble-metal catalysts with highly dense active sites are promising materials with which to maximise metal efficiency and to enhance catalytic performance; however, their fabrication remains challenging because metal atoms are prone to sintering, especially at a high metal...... loading. A dynamic process of formation of isolated metal atom catalytic sites on the surface of the support, which was achieved starting from silver nanoparticles by using a thermal surface-mediated diffusion method, was observed directly by using in situ electron microscopy and in situ synchrotron X...

  16. Etiological study on isolated esophageal atresia

    Energy Technology Data Exchange (ETDEWEB)

    Szendrey, T; Danyi, G; Czeizel, A

    1985-01-01

    A study group of 160 index patients with isolated esophageal atresia, a control group of 160 matched healthy controls, and the first-degree relatives of patients and controls were examined; epidemiological, family planning, teratological, and genetic data were obtained by personal interview in the study and control groups. One half of the index patients were male. Intrauterine growth retardation, a higher proportion of mothers under 19 or over 30 years of age, and less skilled professions of the parents were found in the study group. There were more extramarital conceptions, more pregnancies in spite of the use of contraceptive pills, and more delayed conceptions in index patients mothers. The teratogens studied did not have an obvious pathological effect here. The sib occurrence of isolated esophageal atresia was 0.43%, which did not correspond well to the expected figure of 1.34% based on the polygenic model.

  17. Target materials for exotic ISOL beams

    CERN Document Server

    Gottberg, A

    2016-01-01

    The demand for intensity, purity, reliability and availability of short-lived isotopes far from stability is steadily high, and considerably exceeding the supply. In many cases the ISOL (Isotope Separation On-Line) method can provide beams of high intensity and purity. Limitations in terms of accessible chemical species and minimum half-life are driven mainly by chemical reactions and physical processes inside of the thick target. A wide range of materials are in use, ranging from thin metallic foils and liquids to refractory ceramics, while poly-phasic mixed uranium carbides have become the reference target material for most ISOL facilities world-wide. Target material research and development is often complex and especially important post-irradiation analyses are hindered by the high intrinsic radiotoxicity of these materials. However, recent achievements have proven that these investigations are possible if the effort of different facilities is combined, leading to the development of new material matrices t...

  18. Review of relevant studies of isolated systems

    DEFF Research Database (Denmark)

    Hansen, L.H.; Lundsager, P.

    2001-01-01

    The report presents the results of a review of studies relating to integration of wind energy in isolated power supply systems, based on a systematic literature survey. The purpose of the study is to develop a methodology consisting of a set of guidelinesfor wind energy projects in isolated energy...... systems and a set of tools and models that are operational on an engineering level. The review is based on a literature search in the ETDE Energy Database with a main search covering the period 7/88 to 6/97 andsupplemented by partial update periods. A few newer references have been included in the review...... have been organised according to the following keywords: methods & guides, economics, concept ofapplication, system solutions, case studies, financial programmes, dedicated software tools. None of the found references presents methods or tools that contradict the philosophy of Risø's methodology...

  19. Isolation and biological activity of frankiamide.

    Science.gov (United States)

    Haansuu, J P; Klika, K D; Söderholm, P P; Ovcharenko, V V; Pihlaja, K; Haahtela, K K; Vuorela, P M

    2001-07-01

    An antibiotic produced by the symbiotic actinomycete Frankia strain AiPs1 was isolated from culture broth using optimized thin-layer chromatography and high-performance liquid chromatography (HPLC) methods. The novel compound that was isolated, dubbed frankiamide, displayed antimicrobial activity against all 14 Gram-positive bacterial strains and six pathogenic fungal strains tested. The pathogenic actinomycete Clavibacter michiganensis and the oomycete Phytophthora were especially susceptible. In addition to displaying antimicrobial activity, frankiamide also strongly inhibited 45Ca(2+) fluxes in clonal rat pituitary GH4C1 tumor cells and was comparable to a frequently used calcium antagonist, verapamil hydrochloride. The results of HPLC analysis, supported by both nuclear magnetic resonance and mass spectroscopy studies, showed that frankiamide has a high affinity for Na(+) ions.

  20. Deafblind people, communication, independence, and isolation.

    Science.gov (United States)

    Hersh, Marion

    2013-10-01

    This paper discusses issues related to communication, independence, and isolation for an understudied group of deaf people who also have visual impairments. The discussion is based on the experiences of 28 deafblind people in 6 different countries, obtained from interviews that were carried out as part of a larger research project on travel issues. However, the similarities in experiences between countries were stronger than the differences. In particular, barriers to communication and inadequate support, with resulting problems of isolation and depression, were found in all the countries. Equally, deafblind people in all the countries were interested in being involved in and contributing to society and supporting other people, particularly through organizations of blind and deafblind people. This runs counter to the tendency to present deafblind and other disabled people purely as recipients of support rather than also as active participants in society. However, there were some differences in the support available in the different countries.

  1. Do geographically isolated wetlands influence landscape functions?

    OpenAIRE

    Cohen, Matthew J.; Creed, Irena F.; Alexander, Laurie; Basu, Nandita B.; Calhoun, Aram J. K.; Craft, Christopher; D’Amico, Ellen; DeKeyser, Edward; Fowler, Laurie; Golden, Heather E.; Jawitz, James W.; Kalla, Peter; Kirkman, L. Katherine; Lane, Charles R.; Lang, Megan

    2016-01-01

    Geographically isolated wetlands (GIWs), those surrounded by uplands, exchange materials, energy, and organisms with other elements in hydrological and habitat networks, contributing to landscape functions, such as flow generation, nutrient and sediment retention, and biodiversity support. GIWs constitute most of the wetlands in many North American landscapes, provide a disproportionately large fraction of wetland edges where many functions are enhanced, and form complexes with other water bo...

  2. Active vibration isolation of high precision machines

    CERN Document Server

    Collette, C; Artoos, K; Hauviller, C

    2010-01-01

    This paper provides a review of active control strategies used to isolate high precisionmachines (e.g. telescopes, particle colliders, interferometers, lithography machines or atomic force microscopes) from external disturbances. The objective of this review is to provide tools to develop the best strategy for a given application. Firstly, the main strategies are presented and compared, using single degree of freedom models. Secondly, the case of huge structures constituted of a large number of elements, like particle colliders or segmented telescopes, is considered.

  3. Isolation Mounting for Charge-Coupled Devices

    Science.gov (United States)

    Goss, W. C.; Salomon, P. M.

    1985-01-01

    CCD's suspended by wires under tension. Remote thermoelectric cooling of charge coupled device allows vibration isolating mounting of CCD assembly alone, without having to suspend entire mass and bulk of thermoelectric module. Mounting hardware simple and light. Developed for charge-coupled devices (CCD's) in infrared telescope support adaptable to sensors in variety of environments, e.g., sensors in nuclear reactors, engine exhausts and plasma chambers.

  4. Trypanosoma evansi isolated from capybara (Hidrochaeris hidrochaeris

    Directory of Open Access Journals (Sweden)

    Karina Muñoz

    2001-10-01

    Full Text Available A study was conducted to determine the morphological and biometric characteristics of Trypanosoma isolated from 50 capybaras animals, raised in captivity in the Peruvian Amazon. Trypanosoma was found in 14 blood samples using the microhaematocrit, wide drop, and Giemsa-stain methods and T. evansi was identified through morphological details in all 14 positive samples (the subterminal kinetoplast, the developed undulating membrane, and a long free flagellum were used for the identification of the agent.

  5. Isolated penile metastasis from bladder carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Demuren, O.A. [Department of Radiology and Imaging, Armed Forces Hospital, Riyadh (Saudi Arabia); Koriech, O. [Department of Oncology, Armed Forces Hospital, Riyadh (Saudi Arabia)

    1999-10-01

    Metastases of the penis are uncommon, with only approximately 300 cases reported since 1870. In up to 70 % of patients, the primary tumour is located in the urogenital tract. Furthermore, isolated metastases of the penis are exceptionally rare. We report a case of solitary squamous cell metastasis of the penis presenting with painful swelling initially thought to be inflammatory in origin. The CT and MR imaging findings are presented with a short review of the literature. (orig.) With 2 figs., 9 refs.

  6. Technical program plan, Basalt Waste Isolation Project

    International Nuclear Information System (INIS)

    1979-12-01

    The Basalt Waste Isolation Project (BWIP) program as administered by the DOE's Richland Operations Office and Rockwell Hanford Operations is described. The objectives, scope and scientific technologies are discussed. The work breakdown structure of the project includes: project management and support, systems integration, geosciences, hydrology, engineered barriers, test facility design and construction, engineering testing, repository studies, and schedules. The budget of the program including operating and capital cost control is also included

  7. Exploration of renewable sources for isolated systems

    OpenAIRE

    Apolo, Cristhian Agustin Apolo

    2017-01-01

    Providing universal access to electricity is a priority worldwide. Renewable Energy Sources (RES) play an important role in the supply of energy to rural and remote areas, where grid electricity is not available, or the cost of the grid extension is excessively. Isolated communities in the Amazon region of Ecuador are frequently far away from each other, formed by scattered housing, exhibit very low population density, and are surrounded by dense vegetation. Supplying such communities is typi...

  8. Causes and roentgenographic patterns of isolated bronchoceles

    Energy Technology Data Exchange (ETDEWEB)

    Scheel, W.; Eger, H.

    1986-11-01

    A survey is given of the roentgenographic features of isolated bronchoceles (25 cases: 9 men; 16 women). If some roentgenomorphological peculiarities are taken into consideration, identification is possible via plain radiography and topic related two-dimensional tomography. With regard to preoperative aspects the perception of this disease is very important because the extent of a surgical procedure may not infrequently be limited to a segmental resection.

  9. Causes and roentgenographic patterns of isolated bronchoceles

    International Nuclear Information System (INIS)

    Scheel, W.; Eger, H.

    1986-01-01

    A survey is given of the roentgenographic features of isolated bronchoceles (25 cases: 9 men; 16 women). If some roentgenomorphological peculiarities are taken into consideration, identification is possible via plain radiography and topic related two-dimensional tomography. With regard to preoperative aspects the perception of this disease is very important because the extent of a surgical procedure may not infrequently be limited to a segmental resection. (orig.) [de

  10. Isolated pseudohypoplasia of the right ventricle.

    Science.gov (United States)

    Pastor, Esteban; Aramendi, José I; Luis, Maite; Voces, Roberto; Rodríguez, Miguel A; Galdeano, José M

    2007-08-01

    We present a case of a 12-year-old girl with severe cyanosis due to abnormal moderator band producing a hidden trabecular component of the right ventricle, mimicking isolated hypoplasia of the right ventricle. A marked hypoplasia was confirmed by echocardiography and catheterization. At operation an anomalously thickened moderator band obstructing the apical infundibulum was found. Repair consisted of a section of the moderator band and closure of the atrial septal defect. Postoperatively the right ventricle showed normal dimension and function.

  11. Radioactive-waste isolation pilot plant

    International Nuclear Information System (INIS)

    Weart, W.D.

    1977-01-01

    The objective of the Waste Isolation Pilot Plant (WIPP) program is to demonstrate the suitability of bedded salt, specifically, the bedded salt deposits in the Los Medanos area of southeastern New Mexico, as a disposal medium for radioactive wastes. Our program responsibilities include site selection considerations, all aspects of design and development, technical guidance of facility operation, environmental impact assessment, and technical support to ERDA for developing public understanding of the facility

  12. Bistable (latching) solenoid actuated propellant isolation valve

    Science.gov (United States)

    Wichmann, H.; Deboi, H. H.

    1979-01-01

    The design, fabrication, assembly and test of a development configuration bistable (latching) solenoid actuated propellant isolation valve suitable for the control hydrazine and liquid fluorine to an 800 pound thrust rocket engine is described. The valve features a balanced poppet, utilizing metal bellows, a hard poppet/seat interface and a flexure support system for the internal moving components. This support system eliminates sliding surfaces, thereby rendering the valve free of self generated particles.

  13. Cultural isolation of third-world scientists

    International Nuclear Information System (INIS)

    Sadiq, A.

    1981-10-01

    The isolation of third world scientists from the modes of production and from the culture of their countries seems to be related to the alienation of the urban culture of these countries from their respective rural backgrounds. It is suggested that this alienation may be overcome by directly interfacing modern science and technology to the corresponding elements in their rural culture through the process of education. (author)

  14. Isolation of lytic bacteriophage against Vibrio harveyi.

    Science.gov (United States)

    Crothers-Stomps, C; Høj, L; Bourne, D G; Hall, M R; Owens, L

    2010-05-01

    The isolation of lytic bacteriophage of Vibrio harveyi with potential for phage therapy of bacterial pathogens of phyllosoma larvae from the tropical rock lobster Panulirus ornatus. Water samples from discharge channels and grow-out ponds of a prawn farm in northeastern Australia were enriched for 24 h in a broth containing four V. harveyi strains. The bacteriophage-enriched filtrates were spotted onto bacterial lawns demonstrating that the bacteriophage host range for the samples included strains of V. harveyi, Vibrio campbellii, Vibrio rotiferianus, Vibrio parahaemolyticus and Vibrio proteolyticus. Bacteriophage were isolated from eight enriched samples through triple plaque purification. The host range of purified phage included V. harveyi, V. campbellii, V. rotiferianus and V. parahaemolyticus. Transmission electron microscope examination revealed that six purified phage belonged to the family Siphoviridae, whilst two belonged to the family Myoviridae. The Myoviridae appeared to induce bacteriocin production in a limited number of host bacterial strains, suggesting that they were lysogenic rather than lytic. A purified Siphoviridae phage could delay the entry of a broth culture of V. harveyi strain 12 into exponential growth, but could not prevent the overall growth of the bacterial strain. Bacteriophage with lytic activity against V. harveyi were isolated from prawn farm samples. Purified phage of the family Siphoviridae had a clear lytic ability and no apparent transducing properties, indicating they are appropriate for phage therapy. Phage resistance is potentially a major constraint to the use of phage therapy in aquaculture as bacteria are not completely eliminated. Phage therapy is emerging as a potential antibacterial agent that can be used to control pathogenic bacteria in aquaculture systems. The development of phage therapy for aquaculture requires initial isolation and determination of the bacteriophage host range, with subsequent creation of

  15. Isolation of Retroelement from Plant Genomic DNA

    OpenAIRE

    sprotocols

    2014-01-01

    Author: Pat Heslop-Harrison ### Abstract: Retroelements and their derivatives are an ubiquitous and abundant component of plant genomes. From the 1990s, PCR based techniques have been developed to isolate the elements from genomic DNA of different plants, and the methods and primers used are presented here. Major classes of retroelements include the Ty1-copia, the Ty3-gypsy and the LINE (non-LTR) groups. Mixed PCR products representing the full heterogeneous pool of retrotransposo...

  16. [Initiating psychiatric care for young, isolated foreigners].

    Science.gov (United States)

    Woestelandt, Laure; Touhami, Fatima; Radjack, Rahmeth; Moro, Marie Rose; Lachal, Jonathan

    The various traumatic events experienced by young isolated foreigners can weaken them psychologically and cause psychiatric decompensation. A qualitative study, carried out by the Maison de Solenn and the Avicenne hospital, aimed to provide better understanding of the conditions for initiating psychiatric care with these adolescents. The different results show that this type of care for these young migrants must be cross-cultural and multi-disciplinary. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  17. United States steps up waste isolation programme

    Energy Technology Data Exchange (ETDEWEB)

    Smedes, H W [Department of Energy, Germantown, MD (USA). Office of Waste Isolation; Carbiener, W A [Battelle Columbus Labs., OH (USA)

    1982-11-01

    A description is given of the United States' waste isolation programme which now involves tests of specific sites. The US Department of Energy plans to build a system of mined geological repositories for the disposal of commercially generated high-level and transuranic radioactive waste. It is hoped that the first repository will be available by 1998. Studies of the geology and hydrology of the proposed sites, the waste packaging and the repository design are reported.

  18. Experimental equipment for an advanced ISOL facility

    International Nuclear Information System (INIS)

    Baktash, C.; Lee, I.Y.; Rehm, K.E.

    1999-01-01

    This report summarizes the proceedings and recommendations of the Workshop on the Experimental Equipment for an Advanced ISOL Facility which was held at Lawrence Berkeley National Laboratory on July 22--25, 1998. The purpose of this workshop was to discuss the performance requirements, manpower and cost estimates, as well as a schedule of the experimental equipment needed to fully exploit the new physics which can be studied at an advanced ISOL facility. An overview of the new physics opportunities that would be provided by such a facility has been presented in the White Paper that was issued following the Columbus Meeting. The reactions and experimental techniques discussed in the Columbus White Paper served as a guideline for the formulation of the detector needs at the Berkeley Workshop. As outlined a new ISOL facility with intense, high-quality beams of radioactive nuclei would provide exciting new research opportunities in the areas of: the nature of nucleonic matter; the origin of the elements; and tests of the Standard Model. After an introductory section, the following equipment is discussed: gamma-ray detectors; recoil separators; magnetic spectrographs; particle detectors; targets; and apparatus using non-accelerated beams

  19. Isolation and characterization of novel chitinolytic bacteria

    Science.gov (United States)

    Gürkök, Sümeyra; Görmez, Arzu

    2016-04-01

    Chitin, a linear polymer of β-1,4-N-acetylglucosamine units, is one of the most abundant biopolymers widely distributed in the marine and terrestrial environments. It is found as a structural component of insects, crustaceans and the cell walls of fungi. Chitinases, the enzymes degrading chitin by cleaving the β-(1-4) bond, have gained increased attention due to their wide range of biotechnological applications, especially for biocontrol of harmful insects and phytopathogenic fungi in agriculture. In the present study, 200 bacterial isolates from Western Anatolia Region of Turkey were screened for chitinolytic activity on agar media amended with colloidal chitin. Based on the chitin hydrolysis zone, 13 isolates were selected for further study. Bacterial isolates with the highest chitinase activity were identified as Acinetobacter calcoaceticus, Arthrobacter oxydans, Bacillus cereus, Bacillus megaterium, Brevibacillus reuszeri, Kocuria erythromyxa, Kocuria rosea, Novosphingobium capsulatum, Rhodococcus bratislaviensis, Rhodococcus fascians and Staphylococcus cohnii by MIS and BIOLOG systems. The next aims of the study are to compare the productivity of these bacteria quantitatively, to purify the enzyme from the most potent producer and to apply the pure enzyme for the fight against the phytopathogenic fungi and harmful insects.

  20. Antarctic isolation: immune and viral studies

    Science.gov (United States)

    Tingate, T. R.; Lugg, D. J.; Muller, H. K.; Stowe, R. P.; Pierson, D. L.

    1997-01-01

    Stressful environmental conditions are a major determinant of immune reactivity. This effect is pronounced in Australian National Antarctic Research Expedition populations exposed to prolonged periods of isolation in the Antarctic. Alterations of T cell function, including depression of cutaneous delayed-type hypersensitivity responses and a peak 48.9% reduction of T cell proliferation to the mitogen phytohaemagglutinin, were documented during a 9-month period of isolation. T cell dysfunction was mediated by changes within the peripheral blood mononuclear cell compartment, including a paradoxical atypical monocytosis associated with altered production of inflammatory cytokines. There was a striking reduction in the production by peripheral blood mononuclear cells of the predominant pro-inflammatory monokine TNF-alpha and changes were also detected in the production of IL-1, IL-2, IL-6, IL-1ra and IL-10. Prolonged Antarctic isolation is also associated with altered latent herpesvirus homeostasis, including increased herpesvirus shedding and expansion of the polyclonal latent Epstein-Barr virus-infected B cell population. These findings have important long-term health implications.