Rhodococcus erythropolis and Its γ-Lactone Catabolic Pathway: An Unusual Biocontrol System That Disrupts Pathogen Quorum Sensing Communication

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Xavier Latour

2013-12-01

Full Text Available Rhodococcus erythropolis is an environmental Gram-positive Actinobacterium with a versatile metabolism involved in various bioconversions and degradations. Rhodococci are best known for their great potential in numerous decontamination and industrial processes. However, they can also prevent plant disease by disrupting quorum sensing-based communication of Gram-negative soft-rot bacteria, by degrading N-acyl-homoserine lactone signaling molecules. Such biocontrol activity results partly from the action of the γ-lactone catabolic pathway. This pathway is responsible for cleaving the lactone bond of a wide range of compounds comprising a γ-butyrolactone ring coupled to an alkyl or acyl chain. The aliphatic products of this hydrolysis are then activated and enter fatty acid metabolism. This short pathway is controlled by the presence of the γ-lactone, presumably sensed by a TetR-like transcriptional regulator, rather than the presence of the pathogen or the plant-host in the environment of the Rhodococci. Both the density and biocontrol activity of R. erythropolis may be boosted in crop systems. Treatment with a cheap γ-lactone stimulator, for example, the food flavoring γ-caprolactone, induces the activity in the biocontrol agent, R. erythropolis, of the pathway degrading signaling molecules; such treatments thus promote plant protection.

Biodegradation of benzo[α]pyrene, toluene, and formaldehyde from the gas phase by a consortium of Rhodococcus erythropolis and Fusarium solani.

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Morales, Paulina; Cáceres, Manuel; Scott, Felipe; Díaz-Robles, Luis; Aroca, Germán; Vergara-Fernández, Alberto

2017-09-01

Polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) are important indoor contaminants. Their hydrophobic nature hinders the possibility of biological abatement using biofiltration. Our aim was to establish whether the use of a consortium of Fusarium solani and Rhodococcus erythropolis shows an improved performance (in terms of mineralization rate and extent) towards the degradation of formaldehyde, as a slightly polar VOC; toluene, as hydrophobic VOC; and benzo[α]pyrene (BaP) as PAH at low concentrations compared to a single-species biofilm in serum bottles with vermiculite as solid support to mimic a biofilter and to relate the possible improvements with the surface hydrophobicity and partition coefficient of the biomass at three different temperatures. Results showed that the hydrophobicity of the surface of the biofilms was affected by the hydrophobicity of the carbon source in F. solani but it did not change in R. erythropolis. Similarly, the partition coefficients of toluene and BaP in F. solani biomass (both as pure culture and consortium) show a reduction of up to 38 times compared to its value in water, whereas this reduction was only 1.5 times in presence of R. erythropolis. Despite that increments in the accumulated CO 2 and its production rate were found when F. solani or the consortium was used, the mineralization extent of toluene was below 25%. Regarding BaP degradation, the higher CO 2 production rates and percent yields were obtained when a consortium of F. solani and R. erythropolis was used, despite a pure culture of R. erythropolis exhibits poor mineralization of BaP.

Localization of Low Copy Number Plasmid pRC4 in Replicating Rod and Non-Replicating Cocci Cells of Rhodococcus erythropolis PR4.

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Divya Singhi

Full Text Available Rhodococcus are gram-positive bacteria, which can exist in two different shapes rod and cocci. A number of studies have been done in the past on replication and stability of small plasmids in this bacterium; however, there are no reports on spatial localization and segregation of these plasmids. In the present study, a low copy number plasmid pDS3 containing pRC4 replicon was visualized in growing cells of Rhodococcus erythropolis PR4 (NBRC100887 using P1 parS-ParB-GFP system. Cells were initially cocci and then became rod shaped in exponential phase. Cocci cells were found to be non-replicating as evident by the presence of single fluorescence focus corresponding to the plasmid and diffuse fluorescence of DnaB-GFP. Rod shaped cells contained plasmid either present as one fluorescent focus observed at the cell center or two foci localized at quarter positions. The results suggest that the plasmid is replicated at the cell center and then it goes to quarter position. In order to observe the localization of plasmid with respect to nucleoid, plasmid segregation was also studied in filaments where it was found to be replicated at the cell center in a nucleoid free region. To the best of our knowledge, this is the first report on segregation of small plasmids in R. erythropolis.

Improvement of Biodesulfurization Rate of Alginate Immobilized Rhodococcus erythropolis R1.

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Derikvand, Peyman; Etemadifar, Zahra

2014-03-01

Sulfur oxides released from the burning of oil causes severe environmental pollution. The sulfur can be removed via the 4S pathway in biodesulfurization (BDS). Immobilization approaches have been developed to prevent cell contamination of oil during the BDS process. The encapsulation of Rhodococcus erythropolis R1 in calcium alginate beads was studied in order to enhance conversion of dibenzothiophene (DBT) to 2-hydroxy biphenyl (2-HBP) as the final product. Also the effect of different factors on the BDS process was investigated. Calcium alginate capsules were prepared using peristaltic pumps with different needle sizes to control the beads sizes. Scanning electron microscopy and flow cytometry methods were used to study the distribution and viability of encapsulated cells, respectively. Two non-ionic surfactants and also nano Ƴ-Al2O3were used with the ratio of 0.5% (v/v) and 1:5 (v/v) respectively to investigate their BDS efficiency. In addition, the effect of different bead sizes and different concentrations of sodium alginate in BDS activity was studied. The 2% (w/v) sodium alginate beads with 1.5mm size were found to be the optimum for beads stability and efficient 2-HBP production. The viability of encapsulated cells decreased by 12% after 20 h of desulfurization, compared to free cells. Adding the non-ionic surfactants markedly enhanced the rate of BDS, because of increasing mass transfer of DBT to the gel matrix. In addition, Span 80 was more effective than Tween 80. The nanoƳ-Al2O3 particles could increase BDS rate by up to two-folds greater than that of the control beads. The nano Ƴ-Al2O3 can improve the immobilized biocatalyst for excellent efficiency of DBT desulfurization. Also the BDS activity can be enhanced by setting the other explained factors at optimum levels.

Improvement of phytoremediation of an aged petroleum hydrocarbon-contaminated soil by Rhodococcus erythropolis CD 106 strain.

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Płociniczak, Tomasz; Fic, Ewa; Pacwa-Płociniczak, Magdalena; Pawlik, Małgorzata; Piotrowska-Seget, Zofia

2017-07-03

The aim of this study was to assess the impact of soil inoculation with the Rhodococcus erythropolis CD 106 strain on the effectiveness of the phytoremediation of an aged hydrocarbon-contaminated [approx. 1% total petroleum hydrocarbon (TPH)] soil using ryegrass (Lolium perenne). The introduction of CD 106 into the soil significantly increased the biomass of ryegrass and the removal of hydrocarbons in planted soil. The fresh weight of the shoots and roots of plants inoculated with CD 106 increased by 49% and 30%, respectively. After 210 days of the experiment, the concentration of TPH was reduced by 31.2%, whereas in the planted, non-inoculated soil, it was reduced by 16.8%. By contrast, the concentration of petroleum hydrocarbon decreased by 18.7% in non-planted soil bioaugmented with the CD 106 strain. The rifampicin-resistant CD 106 strain survived after inoculation into soil and was detected in the soil during the entire experimental period, but the number of CD 106 cells decreased constantly during the enhanced phytoremediation and bioaugmentation experiments. The plant growth-promoting and hydrocarbon-degrading properties of CD 106, which are connected with its long-term survival and limited impact on autochthonous microflora, make this strain a good candidate for improving the phytoremediation efficiency of soil contaminated with hydrocarbons.

Improvement of Biodesulfurization Rate of Alginate Immobilized Rhodococcus erythropolis R1

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Derikvand, Peyman; Etemadifar, Zahra

2014-01-01

Background: Sulfur oxides released from the burning of oil causes severe environmental pollution. The sulfur can be removed via the 4S pathway in biodesulfurization (BDS). Immobilization approaches have been developed to prevent cell contamination of oil during the BDS process. Objectives: The encapsulation of Rhodococcus erythropolis R1 in calcium alginate beads was studied in order to enhance conversion of dibenzothiophene (DBT) to 2-hydroxy biphenyl (2-HBP) as the final product. Also the effect of different factors on the BDS process was investigated. Materials and Methods: Calcium alginate capsules were prepared using peristaltic pumps with different needle sizes to control the beads sizes. Scanning electron microscopy and flow cytometry methods were used to study the distribution and viability of encapsulated cells, respectively. Two non-ionic surfactants and also nano Ƴ-Al2O3were used with the ratio of 0.5% (v/v) and 1:5 (v/v) respectively to investigate their BDS efficiency. In addition, the effect of different bead sizes and different concentrations of sodium alginate in BDS activity was studied. Results: The 2% (w/v) sodium alginate beads with 1.5mm size were found to be the optimum for beads stability and efficient 2-HBP production. The viability of encapsulated cells decreased by 12% after 20 h of desulfurization, compared to free cells. Adding the non-ionic surfactants markedly enhanced the rate of BDS, because of increasing mass transfer of DBT to the gel matrix. In addition, Span 80 was more effective than Tween 80. The nanoƳ-Al2O3 particles could increase BDS rate by up to two-folds greater than that of the control beads. Conclusions: The nano Ƴ-Al2O3 can improve the immobilized biocatalyst for excellent efficiency of DBT desulfurization. Also the BDS activity can be enhanced by setting the other explained factors at optimum levels. PMID:25147685

Genome and Proteome Analysis of Rhodococcus erythropolis MI2: Elucidation of the 4,4´-Dithiodibutyric Acid Catabolism

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Khairy, Heba; Meinert, Christina; Wübbeler, Jan Hendrik; Poehlein, Anja; Daniel, Rolf; Voigt, Birgit; Riedel, Katharina; Steinbüchel, Alexander

2016-01-01

Rhodococcus erythropolis MI2 has the extraordinary ability to utilize the xenobiotic 4,4´-dithiodibutyric acid (DTDB). Cleavage of DTDB by the disulfide-reductase Nox, which is the only verified enzyme involved in DTDB-degradation, raised 4-mercaptobutyric acid (4MB). 4MB could act as building block of a novel polythioester with unknown properties. To completely unravel the catabolism of DTDB, the genome of R. erythropolis MI2 was sequenced, and subsequently the proteome was analyzed. The draft genome sequence consists of approximately 7.2 Mbp with an overall G+C content of 62.25% and 6,859 predicted protein-encoding genes. The genome of strain MI2 is composed of three replicons: one chromosome and two megaplasmids with sizes of 6.45, 0.4 and 0.35 Mbp, respectively. When cells of strain MI2 were cultivated with DTDB as sole carbon source and compared to cells grown with succinate, several interesting proteins with significantly higher expression levels were identified using 2D-PAGE and MALDI-TOF mass spectrometry. A putative luciferase-like monooxygenase-class F420-dependent oxidoreductase (RERY_05640), which is encoded by one of the 126 monooxygenase-encoding genes of the MI2-genome, showed a 3-fold increased expression level. This monooxygenase could oxidize the intermediate 4MB into 4-oxo-4-sulfanylbutyric acid. Next, a desulfurization step, which forms succinic acid and volatile hydrogen sulfide, is proposed. One gene coding for a putative desulfhydrase (RERY_06500) was identified in the genome of strain MI2. However, the gene product was not recognized in the proteome analyses. But, a significant expression level with a ratio of up to 7.3 was determined for a putative sulfide:quinone oxidoreductase (RERY_02710), which could also be involved in the abstraction of the sulfur group. As response to the toxicity of the intermediates, several stress response proteins were strongly expressed, including a superoxide dismutase (RERY_05600) and an osmotically induced

Genome and Proteome Analysis of Rhodococcus erythropolis MI2: Elucidation of the 4,4´-Dithiodibutyric Acid Catabolism.

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Heba Khairy

Full Text Available Rhodococcus erythropolis MI2 has the extraordinary ability to utilize the xenobiotic 4,4´-dithiodibutyric acid (DTDB. Cleavage of DTDB by the disulfide-reductase Nox, which is the only verified enzyme involved in DTDB-degradation, raised 4-mercaptobutyric acid (4MB. 4MB could act as building block of a novel polythioester with unknown properties. To completely unravel the catabolism of DTDB, the genome of R. erythropolis MI2 was sequenced, and subsequently the proteome was analyzed. The draft genome sequence consists of approximately 7.2 Mbp with an overall G+C content of 62.25% and 6,859 predicted protein-encoding genes. The genome of strain MI2 is composed of three replicons: one chromosome and two megaplasmids with sizes of 6.45, 0.4 and 0.35 Mbp, respectively. When cells of strain MI2 were cultivated with DTDB as sole carbon source and compared to cells grown with succinate, several interesting proteins with significantly higher expression levels were identified using 2D-PAGE and MALDI-TOF mass spectrometry. A putative luciferase-like monooxygenase-class F420-dependent oxidoreductase (RERY_05640, which is encoded by one of the 126 monooxygenase-encoding genes of the MI2-genome, showed a 3-fold increased expression level. This monooxygenase could oxidize the intermediate 4MB into 4-oxo-4-sulfanylbutyric acid. Next, a desulfurization step, which forms succinic acid and volatile hydrogen sulfide, is proposed. One gene coding for a putative desulfhydrase (RERY_06500 was identified in the genome of strain MI2. However, the gene product was not recognized in the proteome analyses. But, a significant expression level with a ratio of up to 7.3 was determined for a putative sulfide:quinone oxidoreductase (RERY_02710, which could also be involved in the abstraction of the sulfur group. As response to the toxicity of the intermediates, several stress response proteins were strongly expressed, including a superoxide dismutase (RERY_05600 and an

Electrical resistivity tomography to monitor enhanced biodegradation of hydrocarbons with Rhodococcus erythropolis T902.1 at a pilot scale.

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Masy, Thibaut; Caterina, David; Tromme, Olivier; Lavigne, Benoît; Thonart, Philippe; Hiligsmann, Serge; Nguyen, Frédéric

2016-01-01

Petroleum hydrocarbons (HC) represent the most widespread contaminants and in-situ bioremediation remains a competitive treatment in terms of cost and environmental concerns. However, the efficiency of such a technique (by biostimulation or bioaugmentation) strongly depends on the environment affected and is still difficult to predict a priori. In order to overcome these uncertainties, Electrical Resistivity Tomography (ERT) appears as a valuable non-invasive tool to detect soil heterogeneities and to monitor biodegradation. The main objective of this study was to isolate an electrical signal linked to an enhanced bacterial activity with ERT, in an aged HC-contaminated clay loam soil. To achieve this, a pilot tank was built to mimic field conditions. Compared to a first insufficient biostimulation phase, bioaugmentation with Rhodococcus erythropolis T902.1 led to a HC depletion of almost 80% (6900 to 1600ppm) in 3months in the center of the contaminated zone, where pollutants were less bioavailable. In the meantime, lithological heterogeneities and microbial activities (growth and biosurfactant production) were successively discriminated by ERT images. In the future, this cost-effective technique should be more and more transferred to the field in order to monitor biodegradation processes and assist in selecting the most appropriate remediation technique. Copyright © 2015 Elsevier B.V. All rights reserved.

Electrical resistivity tomography to monitor enhanced biodegradation of hydrocarbons with Rhodococcus erythropolis T902.1 at a pilot scale

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Masy, Thibaut; Caterina, David; Tromme, Olivier; Lavigne, Benoît; Thonart, Philippe; Hiligsmann, Serge; Nguyen, Frédéric

2016-01-01

Petroleum hydrocarbons (HC) represent the most widespread contaminants and in-situ bioremediation remains a competitive treatment in terms of cost and environmental concerns. However, the efficiency of such a technique (by biostimulation or bioaugmentation) strongly depends on the environment affected and is still difficult to predict a priori. In order to overcome these uncertainties, Electrical Resistivity Tomography (ERT) appears as a valuable non-invasive tool to detect soil heterogeneities and to monitor biodegradation. The main objective of this study was to isolate an electrical signal linked to an enhanced bacterial activity with ERT, in an aged HC-contaminated clay loam soil. To achieve this, a pilot tank was built to mimic field conditions. Compared to a first insufficient biostimulation phase, bioaugmentation with Rhodococcus erythropolis T902.1 led to a HC depletion of almost 80% (6900 to 1600 ppm) in 3 months in the center of the contaminated zone, where pollutants were less bioavailable. In the meantime, lithological heterogeneities and microbial activities (growth and biosurfactant production) were successively discriminated by ERT images. In the future, this cost-effective technique should be more and more transferred to the field in order to monitor biodegradation processes and assist in selecting the most appropriate remediation technique.

INDUSTRIAL WASTE BIOCONVERSION INTO SURFACTANTS BY Rhodococcus erythropolis ІMV Ас-5017, Acinetobacter calcoaceticus ІMV В-7241 and Nocardia vaccinii ІMV В-7405

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T. P. Pirog

2017-04-01

Full Text Available The aim of the work is to realize an alternative processing of toxic industrial waste into surfactants by strains Rhodococcus erythropolis IMV Ac-5017, Acinetobacter calcoaceticus IMV B-7241 and Nocardia vaccinii IMV B-7405 for remediation of environment. The studied strains were grown in liquid media containing such sources of carbon as waste (fried sunflower oil, technical glycerol (by-product of biodiesel production, and aromatic compounds. The synthesis of surfactants was evaluated by emulsification index, conditional concentration of surfactants and concentration of extracellular surfactants, which was determined gravimetrically after their extraction from supernatant by the mixture of methanol and chloroform. The concentration of oil in water and soil was analyzed by gravimetric method after extraction with hexane. It was shown that with increasing concentration of the inoculum up to 10−15% and two times increase of nitrogen source content in medium containing 7−8% (v/v of crude glycerol, concentration of surfactants synthesized by R. erythropolis IMV Ac-5017, A. calcoaceticus IMV B 7241 and N. vaccinii IMV B-7405 was 3.4; 5.0 and 5.3 g/l, respectively, that is 1.6−1.7 times higher as compared with values on basal medium with the same content of substrate. The maximum concentration (3.9−4.3 g/l of surfactants synthesized by A. calcoaceticus IMV B-7241 on fried sunflower oil (4% was achieved by using the inoculum grown on refined oil. The ability of R. erythropolis IMV Ac-5017, A. calcoaceticus IMV B-7241 and N. vaccinii IMV B-7405 to decompose aromatic compounds (phenol, naphthalene, toluene, hexachlorobenzene, benzoic and N-phenylanthranilic acid with simultaneous synthesis of extracellular metabolites with surface-active and emulsifying properties was established. In the presence of surfactants in the form of culture liquid (5−10%, the degree of degradation of complex oil with heavy metal (Cu2+, Cd2+, Pb2+, 0.01−0.5 mmol

NCBI nr-aa BLAST: CBRC-LAFR-01-0178 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-LAFR-01-0178 ref|YP_345668.1| putative disulfide bond formation protein [Rhodo...coccus erythropolis PR4] dbj|BAE46176.1| putative disulfide bond formation protein [Rhodococcus erythropolis PR4] YP_345668.1 1.3 28% ...

Optimizing Polychlorinated Biphenyl Degradation by Flavonoid-Induced Cells of the Rhizobacterium Rhodococcus erythropolis U23A.

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Thi Thanh My Pham

Full Text Available There is evidence that many plant secondary metabolites may act as signal molecules to trigger the bacterial ability to metabolize polychlorinated biphenyls (PCBs during the rhizoremediation process. However, the bases for the PCB rhizoremediation process are still largely unknown. The rhizobacterium Rhodococcus erythropolis U23A is unable to use flavanone as a growth substrate. However, on the basis of an assay that monitors the amount of 4-chlorobenzoate produced from 4-chlorobiphenyl by cells grown co-metabolically on flavanone plus sodium acetate, this flavonoid was previously found to be a potential inducer of the U23A biphenyl catabolic pathway. In this work, and using the same assay, we identified ten other flavonoids that did not support growth, but that acted as inducers of the U23A biphenyl pathway, and we confirmed flavonoid induction of the biphenyl catabolic pathway using quantitative real-time polymerase chain reaction (RT-qPCR on the bphA gene. We also examined the effect of the growth co-substrate on flavonoid induction. Sodium acetate was replaced by glucose, mannose, sucrose, or mannitol, which are sugars found in plant root exudates. The data showed that the level of induction of strain U23A biphenyl-degrading enzymes was significantly influenced by the nature and concentration of the flavonoid in the growth medium, as well as by the substrate used for growth. Sucrose allowed for an optimal induction response for most flavonoids. Some flavonoids, such as flavone and isoflavone, were better inducers of the biphenyl catabolic enzymes than biphenyl itself. We also found that all flavonoids tested in this work were metabolized by strain U23A during co-metabolic growth, but that the metabolite profiles, as well as the level of efficiency of degradation, differed for each flavonoid. To obtain insight into how flavonoids interact with strain U23A to promote polychlorinated biphenyl (PCB degradation, we determined the concentration of

Growth and Desulfurization Kinetics of Rhodcoccus Erythropolis IGTS8 on Dibenzothiophen and Petroleum Fraction

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El-Temtamy, S.A.; Farahat, L.A.; Mostafa, Y.M.; Al-Shatnawi, D.F.; AI-Sayed, S.

2004-01-01

The growth Kinetics of Rhodococcus erythropolis IGTS8 on dibenzo-thiophene. DBT, of different initial concentrations as well as on two petroleum fractions namely untreated and hydrodesulfurized gasoline and gas oil have been investigated in batch cultures. Using dibenzothiophene as a substrate, the specific growth rates were found to decrease with increasing initial substrate concentration. The removal of dibenzothiophene from culture media was found to follow first order kinetics. The reaction rate constant., k, decreased with increasing substrate concentration. The decrease of both specific growth rate and reaction rate constant with increasing substrate concentration suggested substrate inhibition. The growth rate on untreated gasoline as well as on hydrodesulfurized gasoline gave nearly the same specific growth rates of 0.067 h-I while growth on gas oil gave a higher specific growth rate of 0.1h -1

Rhodococcus antrifimi sp. nov., isolated from dried bat dung of a cave.

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Ko, Kwan Su; Kim, Youngju; Seong, Chi Nam; Lee, Soon Dong

2015-11-01

A Gram-reaction-positive, high DNA G+C content, non-motile actinobacterium, strain D7-21T, was isolated from dried bat dung inside a natural cave and its taxonomic status was examined by using a polyphasic approach. The 16S rRNA gene sequence study showed that the isolate belonged to the genus Rhodococcus and formed a cluster with Rhodococcus defluvii (98.98 % gene similarity), Rhodococcus equi (98.62 %) and Rhodococcus kunmingensis (97.66 %). Whole-cell hydrolysates contained meso-diaminopimelic acid, arabinose and galactose as the diagnostic diamino acid and sugars. MK-8(H2) was the predominant menaquinone. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside, an unknown phosphoglycolipid and an unknown glycolipid. Mycolic acids were present. The major fatty acids were C16 : 0, C18 : 1ω9c and 10-methyl C18 : 0. The DNA G+C content was 70.1 mol%. A battery of phenotypic features and DNA-DNA relatedness data support that strain D7-21T ( = KCTC 29469T = DSM 46727T) represents a novel species of the genus Rhodococcus, for which Rhodococcus antrifimi sp. nov. is proposed.

Biofouling inhibition in MBR by Rhodococcus sp. BH4 isolated from real MBR plant.

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Oh, Hyun-Suk; Kim, Sang-Ryoung; Cheong, Won-Suk; Lee, Chung-Hak; Lee, Jung-Kee

2013-12-01

It has been reported that an indigenous quorum quenching bacterium, Rhodococcus sp. BH4, which was isolated from a real plant of membrane bioreactor (MBR) has promising potential to control biofouling in MBR. However, little is known about quorum quenching mechanisms by the strain BH4. In this study, various characteristics of strain BH4 were investigated to elucidate its behavior in more detail in the mixed liquor of MBR. The N-acyl homoserine lactone hydrolase (AHL-lactonase) gene of strain BH4 showed a high degree of identity to qsdA in Rhodococcus erythropolis W2. The LC-ESI-MS analysis of the degradation product by strain BH4 confirmed that it inactivated AHL activity by hydrolyzing the lactone bond of AHL. It degraded a wide range of N-acyl homoserine lactones (AHLs), but there was a large difference in the degradation rate of each AHL compared to other reported AHL-lactonase-producing strains belonging to Rhodococcus genus. Its quorum quenching activity was confirmed not only in the Luria-Bertani medium, but also in the synthetic wastewater. Furthermore, the amount of strain BH4 encapsulated in the vessel as well as the material of the vessel substantially affected the quorum quenching activity of strain BH4, which provides useful information, particularly for the biofouling control in a real MBR plant from an engineering point of view.

Growth Kinetics of Rhodococcus Erythropolis IGTS8 on Thiophene and Dimethylsulphoxide

International Nuclear Information System (INIS)

El-Temtamy, S.A.; Farahat, L.A.; Al-Shatnawi, D.F.; AI-Sayed, S.

2004-01-01

Sulfur oxides emissions through fossil fuel combustion posse environmental problems because these oxides are major cause of acid rain, which dissolve buildings, kills forests and poisons lakes. That is why world environmental regulations are becoming harder with respect to sulfur content in fossil fuels. The demand for new low-cost desulfurization technologies has led to renewed interest in bio desulfurization. In this work the growth kinetics of Rhodococcus Erythopolis IGTS8 have been studied on two model sulfur compounds that are found among other sulfur compounds in petroleum fractions. These are namely thiophene and dimethyl sulfoxide, DEMSO. Batch reactor and different substrate concentrations ranging between 1 and 8 gl -1 were used to study the growth kinetics. Growth on thiophene was shown to follow Monode kinetics with μ m ax =0.064 h -1 and K s = 2.8 gl -1 , on the other hand, growth on DEMSO was found to be substrate inhibited

Bio-surfactants production from low cost substrate and degradation of diesel oil by a Rhodococcus strain

International Nuclear Information System (INIS)

Sadouk, Z.; Tazerouti, A.; Sadouk, Z.; Hacene, H.

2008-01-01

The ability of a Rhodococcus strain to produce surface-active agents from residual sunflower frying oil (RSFO) has been screened in batch cultures. During cultivation with RSFO at the concentration 3% (vol/vol), the strain has synthesized extra-cellular compounds which increase the E 24 emulsion index of the culture medium up to 63%. In their crude form, these substances lower the surface tension of water until 31.9 mN m -1 . The exponential growth with RSFO as the sole carbon source has developed at a specific growth rate μ = 0.55 d -1 . The critical micelle concentration of the crude product reached the value 287 mg L -1 (γCMC = 31.9 mN m -1 ). After methyl-esterification, the lipid fraction of bio-surfactants has been analyzed by GC-MS in EI, which reveals the presence of fatty acid methyl esters. The microorganism was also cultivated with the diesel oil as the sole carbon source at the concentration 1% (vol/vol): the active growth phase has developed at rate = 0.02 d -1 , without production of emulsifying substance: the microorganism seems to develop different modes of substrate uptake, according to the nature of the carbon source. The potential use of surface-active agents synthesized on RSFO by Rhodococcus erythropolis 16 LM.USTHB is in the oil industry with minimum purity specification, so that crude preparation could be used, at low cost, in clean-up of hydrocarbons contaminated sites and for enhanced oil recovery. (authors)

Bio-surfactants production from low cost substrate and degradation of diesel oil by a Rhodococcus strain; Production de biosurfactants sur un substrat economique et degradation du gasoil par une souche du genre Rhodococcus

Energy Technology Data Exchange (ETDEWEB)

Sadouk, Z.; Tazerouti, A. [Universite des Sciences et de la Technologie H. Boumediene (USTHB), Lab. de Synthese Organique, Faculte de Chimie, Algiers (Algeria); Sadouk, Z.; Hacene, H. [Universite des Sciences et de la Technologie H. Boumediene (USTHB), Lab. de Microbiologie, Faculte des Sciences Biologiques, Algiers (Algeria)

2008-07-01

The ability of a Rhodococcus strain to produce surface-active agents from residual sunflower frying oil (RSFO) has been screened in batch cultures. During cultivation with RSFO at the concentration 3% (vol/vol), the strain has synthesized extra-cellular compounds which increase the E{sub 24} emulsion index of the culture medium up to 63%. In their crude form, these substances lower the surface tension of water until 31.9 mN m{sup -1}. The exponential growth with RSFO as the sole carbon source has developed at a specific growth rate {mu} = 0.55 d{sup -1}. The critical micelle concentration of the crude product reached the value 287 mg L{sup -1} ({gamma}CMC = 31.9 mN m{sup -1}). After methyl-esterification, the lipid fraction of bio-surfactants has been analyzed by GC-MS in EI, which reveals the presence of fatty acid methyl esters. The microorganism was also cultivated with the diesel oil as the sole carbon source at the concentration 1% (vol/vol): the active growth phase has developed at rate = 0.02 d{sup -1}, without production of emulsifying substance: the microorganism seems to develop different modes of substrate uptake, according to the nature of the carbon source. The potential use of surface-active agents synthesized on RSFO by Rhodococcus erythropolis 16 LM.USTHB is in the oil industry with minimum purity specification, so that crude preparation could be used, at low cost, in clean-up of hydrocarbons contaminated sites and for enhanced oil recovery. (authors)

MICROBIAL SURFACTANTS. I. GLYCOLIPIDS

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Pirog T. Р.

2014-02-01

Full Text Available The review is devoted to surface-active glycolipids. The general characteristics, the physiological role of the rhamnolipids, trehalose lipids, sophorolipids, mannosylerythritol lipids and their traditional producers — the representatives of the genera Pseudozyma, Pseudomonas, Rhodococcus and Candida are given. The detailed analysis of the chemical structure, the stages of the biosynthesis and the regulation of some low molecular glycolipids are done. The own experimental data concerning the synthesis intensification, the physiological role and the practical use of Rhodococcus erythropolis IMV Ac-5017, Acinetobacter calcoaceticus IMV B-7241 and Nocardia vaccinii IMV B-7405 surfactants, which are a complex of the glyco-, phospho-, amino- and neutral lipids (glycolipids of all strains are presented by trehalose mycolates are summarized. It was found that R. erythropolis IMV Ac-5017, A. calcoaceticus IMV B-7241 and N. vaccinii IMV B-7405 surfactants have protective, antimicrobial and antiadhesive properties. It was shown that R. erythropolis IMV Ac-5017, A. calcoaceticus IMV B-7241 and N. vaccinii IMV B-7405 surfactants preparation of cultural liquid intensified the degradation of oil in water due to the activation of the natural petroleum-oxidizing microflora.

Cloning systems for Rhodococcus and related bacteria

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Finnerty, W.R.; Singer, M.E.

1990-08-28

A plasmid transformation system for Rhodococcus was developed using an Escherichia coli-Rhodococcus shuttle plasmid. Rhodococcus sp. H13-A contains three cryptic indigenous plasmids, designated pMVS100, pMVS200 and pMVS300, of 75, 19.5 and 13.4 kilobases (Kb), respectively. A 3.8 Kb restriction fragment of pMVS300 was cloned into pIJ30, a 6.3 Kb pBR322 derivative, containing the E. coli origin of replication (ori) and ampicillin resistance determinant (bla) as well as a Streptomyces gene for thiostrepton resistance, tsr. The resulting 10.1 Kb recombinant plasmid, designated pMVS301, was isolated from E. coli DH1 (pMVS301) and transformed into Rhodococcus sp. AS-50, a derivative of strain H13-A, by polyethylene glycol-assisted transformation of Rhodococcus protoplasts and selection for thiostrepton-resistant transformants. This strain was deposited with the ATCC on Feb. 1, 1988 and assigned ATCC 53719. The plasmid contains the Rhodococcus origin of replication. The plasmid and derivatives thereof can therefore be used to introduce nucleic acid sequences to and from Rhodococcus for subsequent expression and translation into protein. The isolated origin of replication can also be used in the construction of new vectors. 2 figs.

GenBank blastx search result: AK062096 [KOME

Lifescience Database Archive (English)

Full Text Available AK062096 001-044-H12 U17130.1 Rhodococcus erythropolis ORF6' gene, partial cds, regulatory protein ThcR (thc...R), cytochrome P-450 (thcB), ORF4, rhodocoxin (thcC), rhodocoxin reductase (thcD) and ORF5 genes, complete cds.|BCT BCT 3e-18 +3 ...

Aromatic-aliphatic copolyesters based on waste poly(ethylene terephthalate) and their biodegradability

Czech Academy of Sciences Publication Activity Database

Prokopová, I.; Vlčková, E.; Šašek, Václav; Náhlík, J.; Soukupová-Chaloupková, V.; Skolil, J.

-, 052 (2008), s. 1-9 ISSN 1618-7229 R&D Projects: GA ČR GA203/03/0508; GA ČR GA203/06/0528 Institutional research plan: CEZ:AV0Z50200510 Keywords : aromatic-aliphatic colpolyesters * rhodococcus erythropolis * biodegradability Subject RIV: EE - Microbiology, Virology Impact factor: 0.661, year: 2008

Biotransformation of nitriles to hydroxamic acids via a nitrile hydratase–amidase cascade reaction

Czech Academy of Sciences Publication Activity Database

Vejvoda, Vojtěch; Martínková, Ludmila; Veselá, Alicja Barbara; Kaplan, Ondřej; Lutz-Wahl, S.; Fischer, L.; Uhnáková, Bronislava

2011-01-01

Roč. 71, 1-2 (2011), s. 51-55 ISSN 1381-1177 R&D Projects: GA MŠk(CZ) LC06010; GA MŠk OC09046 Institutional research plan: CEZ:AV0Z50200510 Keywords : Nitrile hydratase * Rhodococcus erythropolis * Amidase Subject RIV: EE - Microbiology, Virology Impact factor: 2.735, year: 2011

Molecular characterization of three 3-ketosteroid-Δ(1)-dehydrogenase isoenzymes of Rhodococcus ruber strain Chol-4.

Science.gov (United States)

Fernández de las Heras, Laura; van der Geize, Robert; Drzyzga, Oliver; Perera, Julián; María Navarro Llorens, Juana

2012-11-01

Rhodococcus ruber strain Chol-4 isolated from a sewage sludge sample is able to grow on minimal medium supplemented with steroids, showing a broad catabolic capacity. This paper reports the characterization of three different 3-ketosteroid-Δ(1)-dehydrogenases (KstDs) in the genome of R. ruber strain Chol-4. The genome of this strain does not contain any homologues of a 3-keto-5α-steroid-Δ(4)-dehydrogenase (Kst4d or TesI) that appears in the genomes of Rhodococcus erythropolis SQ1 or Comamonas testosteroni. Growth experiments with kstD2 mutants, either a kstD2 single mutant, kstD2 double mutants in combination with kstD1 or kstD3, or the triple kstD1,2,3 mutant, proved that KstD2 is involved in the transformation of 4-androstene-3,17-dione (AD) to 1,4-androstadiene-3,17-dione (ADD) and in the conversion of 9α-hydroxy-4-androstene-3,17-dione (9OHAD) to 9α-hydroxy-1,4-androstadiene-3,17-dione (9OHADD). kstD2,3 and kstD1,2,3 R. ruber mutants (both lacking KstD2 and KstD3) did not grow in minimal medium with cholesterol as the only carbon source, thus demonstrating the involvement of KstD2 and KstD3 in cholesterol degradation. In contrast, mutation of kstD1 does not alter the bacterial growth on the steroids tested in this study and therefore, the role of this protein still remains unclear. The absence of a functional KstD2 in R. ruber mutants provoked in all cases an accumulation of 9OHAD, as a branch product probably formed by the action of a 3-ketosteroid-9α-hydroxylase (KshAB) on the AD molecule. Therefore, KstD2 is a key enzyme in the AD catabolism pathway of R. ruber strain Chol-4 while KstD3 is involved in cholesterol catabolism. Copyright © 2012 Elsevier Ltd. All rights reserved.

The genus Dracunculus – A source of triacylglycerols containing odd-numbered ω-phenyl fatty acids

Czech Academy of Sciences Publication Activity Database

Řezanka, Tomáš; Schreiberová, O.; Čejková, A.; Sigler, Karel

2011-01-01

Roč. 72, 14-15 (2011), s. 1914-1926 ISSN 0031-9422 R&D Projects: GA ČR(CZ) GAP503/11/0215; GA MŠk 2B08062 Institutional research plan: CEZ:AV0Z50200510 Keywords : Dracunculus vulgaris * Rhodococcus erythropolis * RP-HPLC/MS-APCI Subject RIV: EE - Microbiology, Virology Impact factor: 3.351, year: 2011

Effect of Rhodococcus sp. on desulfurization, swelling and extraction of coal

Energy Technology Data Exchange (ETDEWEB)

Wang De-qiang; Shui Heng-fu [University of Technology of Anhui, Maanshang (China). School of Chemical Engineering

2006-08-15

Bio-desulfurization of coal by rhodococcus sp. was studied. Some kinds of coal were swelled with different organic solvents, and then the swelled coals were treated by rhodococcus sp. The results show that the ratios of desulfurization of coals increase after they are swelled, especially swelled with NMP, the ratio is more than 80%. The swelling and extraction of coal were also studied after the coal had been treated by rhodococcus sp. The results show that the ratios of swelling increase more than 65%, but the extraction yield decreases for the coal treated by rhodococcus sp. 11 refs., 5 tabs.

Rhodococcus bacteremia in cancer patients is mostly catheter related and associated with biofilm formation.

Directory of Open Access Journals (Sweden)

Fadi Al Akhrass

Full Text Available Rhodococcus is an emerging cause of opportunistic infection in immunocompromised patients, most commonly causing cavitary pneumonia. It has rarely been reported as a cause of isolated bacteremia. However, the relationship between bacteremia and central venous catheter is unknown. Between 2002 and 2010, the characteristics and outcomes of seventeen cancer patients with Rhodococcus bacteremia and indwelling central venous catheters were evaluated. Rhodococcus bacteremias were for the most part (94% central line-associated bloodstream infection (CLABSI. Most of the bacteremia isolates were Rhodococcus equi (82%. Rhodococcus isolates formed heavy microbial biofilm on the surface of polyurethane catheters, which was reduced completely or partially by antimicrobial lock solution. All CLABSI patients had successful response to catheter removal and antimicrobial therapy. Rhodococcus species should be added to the list of biofilm forming organisms in immunocompromised hosts and most of the Rhodococcus bacteremias in cancer patients are central line associated.

Coaggregation between Rhodococcus and Acinetobacter strains isolated from the food industry.

Science.gov (United States)

Møretrø, Trond; Sharifzadeh, Shahab; Langsrud, Solveig; Heir, Even; Rickard, Alexander H

2015-07-01

In this study, coaggregation interactions between Rhodococcus and Acinetobacter strains isolated from food-processing surfaces were characterized. Rhodococcus sp. strain MF3727 formed intrageneric coaggregates with Rhodococcus sp. strain MF3803 and intergeneric coaggregates with 2 strains of Acinetobacter calcoaceticus (MF3293, MF3627). Stronger coaggregation between A. calcoaceticus MF3727 and Rhodococcus sp. MF3293 was observed after growth in batch culture at 30 °C than at 20 °C, after growth in tryptic soy broth than in liquid R2A medium, and between cells in exponential and early stationary phases than cells in late stationary phase. The coaggregation ability of Rhodococcus sp. MF3727 was maintained even after heat and Proteinase K treatment, suggesting its ability to coaggregate was protein independent whereas the coaggregation determinants of the other strains involved proteinaceous cell-surface-associated polymers. Coaggregation was stable at pH 5-9. The mechanisms of coaggregation among Acinetobacter and Rhodococcus strains bare similarity to those displayed by coaggregating bacteria of oral and freshwater origin, with respect to binding between proteinaceous and nonproteinaceous determinants and the effect of environmental factors on coaggregation. Coaggregation may contribute to biofilm formation on industrial food surfaces, protecting bacteria against cleaning and disinfection.

Trehalolipid biosurfactants from nonpathogenic Rhodococcus actinobacteria with diverse immunomodulatory activities.

Science.gov (United States)

Kuyukina, Maria S; Ivshina, Irena B; Baeva, Tatiana A; Kochina, Olesia A; Gein, Sergey V; Chereshnev, Valery A

2015-12-25

Actinobacteria of the genus Rhodococcus produce trehalolipid biosurfactants with versatile biochemical properties and low toxicity. In recent years, these biosurfactants are increasingly studied as possible biomedical agents with expressed immunological activities. Applications of trehalolipids from Rhodococcus, predominantly cell-bound, in biomedicine are also attractive because their cost drawback could be less significant for high-value products. The review summarizes recent findings in immunomodulatory activities of trehalolipid biosurfactants from nonpathogenic Rhodococcus and related actinobacteria and compares their biomedical potential with well-known immunomodifying properties of trehalose dimycolates from Mycobacterium tuberculosis. Molecular mechanisms of trehalolipid interactions with immunocompetent cells are also discussed. Copyright © 2015. Published by Elsevier B.V.

Bacteremia por Rhodococcus equi em paciente com síndrome da imunodeficiência adquirida: relato de caso Bacteremia due to Rhodococcus equi in a patient with acquired immunodeficiency syndrome: case report

Directory of Open Access Journals (Sweden)

Carina Secchi

2006-12-01

Full Text Available Rhodococcus equi é um importante agente de infecções zoonóticas, podendo causar sérias infecções em humanos, principalmente em pacientes imunocomprometidos. Neste estudo, nós relatamos o caso de uma bacteremia fatal devido a Rhodococcus equi em paciente com síndrome da imunodeficiência adquirida (HIV positivo.Rhodococcus equi is an important agent for zoonotic infections, and may cause serious infections in humans, especially immunocompromised patients. In this study, a case of fatal bacteremia due to Rhodococcus equi in a patient with acquired immunodeficiency syndrome (HIV positive is reported.

Radiological findings in three acquired immunodeficiency syndrome patients with Rhodococcus equi pneumonia

International Nuclear Information System (INIS)

Liu Jinxin; Tang Xiaoping; Zhang Lieguang

2011-01-01

Objective: To study the imaging appearances of Rhodococcus equi pneumonia in three patients with acquired immunodeficiency syndrome ( AIDS). Methods: Thoracic imaging appearances of' Rhodococcus equi pneumonia in three patients with AIDS were retrospectively analyzed. Results: The chest radiograph showed patchy consolidations and small nodules (n=3), large consolidations with multiple cavitations (n=2). CT showed large lobar or segmental consolidations with multiple cavitations (n=2), patchy consolidations (n=2), bronchiectasis (n=1), multiple small centrilobular nodules (n=2) and tree-in-bud patterns (n=2). Conclusion: The most common radiological findings in AIDS patients with Rhodococcus equi pulmonary infection are large consolidations with multiple cavitations and multiple centrilobular nodules. (authors)

Seroprevalence of Rhodococcus equi in horses in Israel.

Science.gov (United States)

Tirosh-Levy, Sharon; Gürbilek, Sevil E; Tel, Osman Y; Keskin, Oktay; Steinman, Amir

2017-06-26

Rhodococcus equi is a common cause of pneumonia in foals and has extensive clinical, economic and possibly zoonotic consequences. This bacterium survives well in the environment and may be considered as normal flora of adult horses. Certain strains of this bacterium are extremely virulent in foals, and early identification and intervention is crucial for prognosis. Rhodococcus equi is endemic in many parts of the world and occasionally isolated in Israel. This study was designed to evaluate R. equi seroprevalence in adult horses in Israel to indirectly indicate the potential level of exposure of susceptible foals. Sera were collected from 144 horses during spring 2011 and from 293 horses during fall 2014, and the presence of antibodies against virulent R. equi was detected by enzyme-linked immunosorbent assay. Equine seroprevalence of R. equi was found to be 7.6% in 2011 and 5.1% in 2014. Only one farm had seropositive horses in 2011, whereas several farms had seropositive horses in 2014. No significant risk factors for seropositivity were found. Rhodococcus equi appears to be endemic in Israel. This is the first survey of R. equi in Israel that provides information on the epidemiology of this important bacterium.

Nd{sub 39}Ir{sub 10.98}In{sub 36.02}. A complex intergrowth structure with CsCl- and AlB{sub 2}-related slabs

Energy Technology Data Exchange (ETDEWEB)

Dominyuk, Nataliya; Zaremba, Vasyl' I. [Ivan Franko National Univ., Lviv (Ukraine). Dept. of Inorganic Chemistry; Rodewald, Ute C.; Poettgen, Rainer [Muenster Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie

2015-11-01

The ternary indide Nd{sub 39}Ir{sub 10.98}In{sub 36.02} was synthesized by arc-melting and characterized by single crystal X-ray diffraction. Nd{sub 39}Ir{sub 10.98}In{sub 36.02} crystallizes with a new structure type: Pearson code oP172, Pbam, a = 3175.4(6), b = 3762.5(8), c = 378.02(8) pm, wR2 = 0.0828, 5544 F{sup 2} values, and 262 variables. Although the structure contains 44 crystallographically independent sites, it can easily be explained as an intergrowth structure of CsCl and AlB{sub 2} related slabs. The larger indium atoms fill all distorted CsCl slabs. The trigonal prismatic (AlB{sub 2}) slabs have no uniform size. The larger ones are filled by indium and the smaller ones by the iridium atoms. Additionally, one trigonal prism shows a mixed occupancy by indium and iridium. The crystal chemistry of Nd{sub 39}Ir{sub 10.98}In{sub 36.02} is discussed in the context of other intergrowth structures with the same simple slabs.

Evolutionary transitions between beneficial and phytopathogenic Rhodococcus challenge disease management.

Science.gov (United States)

Savory, Elizabeth A; Fuller, Skylar L; Weisberg, Alexandra J; Thomas, William J; Gordon, Michael I; Stevens, Danielle M; Creason, Allison L; Belcher, Michael S; Serdani, Maryna; Wiseman, Michele S; Grünwald, Niklaus J; Putnam, Melodie L; Chang, Jeff H

2017-12-12

Understanding how bacteria affect plant health is crucial for developing sustainable crop production systems. We coupled ecological sampling and genome sequencing to characterize the population genetic history of Rhodococcus and the distribution patterns of virulence plasmids in isolates from nurseries. Analysis of chromosome sequences shows that plants host multiple lineages of Rhodococcus , and suggested that these bacteria are transmitted due to independent introductions, reservoir populations, and point source outbreaks. We demonstrate that isolates lacking virulence genes promote beneficial plant growth, and that the acquisition of a virulence plasmid is sufficient to transition beneficial symbionts to phytopathogens. This evolutionary transition, along with the distribution patterns of plasmids, reveals the impact of horizontal gene transfer in rapidly generating new pathogenic lineages and provides an alternative explanation for pathogen transmission patterns. Results also uncovered a misdiagnosed epidemic that implicated beneficial Rhodococcus bacteria as pathogens of pistachio. The misdiagnosis perpetuated the unnecessary removal of trees and exacerbated economic losses.

Seroprevalence of Rhodococcus equi in horses in Israel

Directory of Open Access Journals (Sweden)

Sharon Tirosh-Levy

2017-06-01

Full Text Available Rhodococcus equi is a common cause of pneumonia in foals and has extensive clinical, economic and possibly zoonotic consequences. This bacterium survives well in the environment and may be considered as normal flora of adult horses. Certain strains of this bacterium are extremely virulent in foals, and early identification and intervention is crucial for prognosis. Rhodococcus equi is endemic in many parts of the world and occasionally isolated in Israel. This study was designed to evaluate R. equi seroprevalence in adult horses in Israel to indirectly indicate the potential level of exposure of susceptible foals. Sera were collected from 144 horses during spring 2011 and from 293 horses during fall 2014, and the presence of antibodies against virulent R. equi was detected by enzyme-linked immunosorbent assay. Equine seroprevalence of R. equi was found to be 7.6% in 2011 and 5.1% in 2014. Only one farm had seropositive horses in 2011, whereas several farms had seropositive horses in 2014. No significant risk factors for seropositivity were found. Rhodococcus equi appears to be endemic in Israel. This is the first survey of R. equi in Israel that provides information on the epidemiology of this important bacterium.

Biodegradation potential of the genus Rhodococcus

Czech Academy of Sciences Publication Activity Database

Martínková, Ludmila; Uhnáková, Bronislava; Pátek, Miroslav; Nešvera, Jan; Křen, Vladimír

2009-01-01

Roč. 35, č. 1 (2009), s. 162-177 ISSN 0160-4120 R&D Projects: GA MŠk(CZ) LC06010; GA MŠk 2B06151 Institutional research plan: CEZ:AV0Z50200510 Keywords : rhodococcus * aromatics * nitriles Subject RIV: EE - Microbiology, Virology Impact factor: 4.786, year: 2009

Analysis of 137Cs radionuclides activities in Cs-zeolite using gamma spectrometry

International Nuclear Information System (INIS)

Noviarty; Ginting, Aslina Br; Anggraini, Dian; Rosika K

2013-01-01

137 Cs Radionuclide activity analysis has been carried out. The objective is to determine the activity of the 137 Cs radionuclide in Cs-zeolite are packaged in the form of point source. Analysis of 137 Cs Radionuclide activities in Cs zeolite samples was determined by measuring intensity of the isotope 137 Cs gamma energy at 661.7 keV use-y spectrometer. Before measurement the sample, was first carried out measurements of 137 Cs radionuclide in certified point standards from Amersham, to determine the efficiency value. Result the standard sample measurement obtained the efficiency value of 43.98%. Efficiency values obtained are used in the calculation of sample activity. On the measurement of the intensity of the sample obtained results dose rate 196.4537 cps with a standard deviation of 0.5274. By using standard measurement efficiency values obtained by the calculation of the average activity of the radionuclide 137 Cs in Cs-zeolite 524.9082 Bq. Deviation measurements were below 5% (0.27% ) so that the analysis of the activity of radionuclide 137 Cs in Cs-zeolite samples using gamma spectrometer can be accepted with a 95% confidence level. (author)

Molecular biological enhancement of coal biodesulfurization. [Rhodococcus rhodochrous

Energy Technology Data Exchange (ETDEWEB)

Kilbane, J.J.; Bielaga, B.A.

1990-07-01

The overall objective of this project is to sue molecular genetics to develop strains of bacteria with enhanced ability to remove sulfur from coal and to obtain data that will allow the performance and economics of a coal biodesulfurization process to be predicted. The work planned for the current quarter (May 1990 to July 1990) includes the following activities: (1) Construct a cloning vector that can be used in Rhodococcus rhodochrous IGTS8 from the small cryptic plasmid found in Rhodococcus rhodochrous ATCC 190607; (2) Develop techniques for the genetic analysis of IGTS8; (3) Continue biochemical experiments, particularly those that may allow the identification of desulfurization-related enzymes; (4) Continue experiments with coal to determine the kinetics of organic sulfur removal.

Successful treatment of Rhodococcus equi pulmonary infection in a renal transplant recipient.

OpenAIRE

Marsh, H. P.; Bowler, I. C.; Watson, C. J.

2000-01-01

The rhodococcus is a mycobacterium-like organism which is normally a pathogen in foals. It usually spreads by direct contact or by aerosol from horse faeces and causes pyogranulomatous pulmonary infections. Occasionally, it acts opportunistically to infect immuno-compromised human hosts, most commonly those with the acquired immune deficiency syndrome (AIDS). Here we report a pulmonary infection by Rhodococcus equi in a renal transplant recipient who was successfully treated. The literature o...

Isolation and characterization of Rhodococcus ruber CGMCC3090 ...

African Journals Online (AJOL)

STORAGESEVER

2009-10-19

Oct 19, 2009 ... Available online at http://www.academicjournals.org/AJB. ISSN 1684–5315 .... the soil samples by an enrichment culture method in basal medium containing 0.5 ..... The phylogeny of the genus Rhodococcus currently remains ...

Complete Genome Sequence of a Rhodococcus Species Isolated from the Winter Skate Leucoraja ocellata.

Science.gov (United States)

Wiens, Julia; Ho, Ryan; Fernando, Dinesh; Kumar, Ayush; Loewen, Peter C; Brassinga, Ann Karen C; Anderson, W Gary

2016-09-01

We report here a genome sequence for Rhodococcus sp. isolate UM008 isolated from the renal/interrenal tissue of the winter skate Leucoraja ocellata Genome sequence analysis suggests that Rhodococcus bacteria may act in a novel mutualistic relationship with their elasmobranch host, serving as biocatalysts in the steroidogenic pathway of 1α-hydroxycorticosterone. Copyright © 2016 Wiens et al.

The detection and phylogenetic analysis of the alkane 1-monooxygenase gene of members of the genus Rhodococcus.

Science.gov (United States)

Táncsics, András; Benedek, Tibor; Szoboszlay, Sándor; Veres, Péter G; Farkas, Milán; Máthé, István; Márialigeti, Károly; Kukolya, József; Lányi, Szabolcs; Kriszt, Balázs

2015-02-01

Naturally occurring and anthropogenic petroleum hydrocarbons are potential carbon sources for many bacteria. The AlkB-related alkane hydroxylases, which are integral membrane non-heme iron enzymes, play a key role in the microbial degradation of many of these hydrocarbons. Several members of the genus Rhodococcus are well-known alkane degraders and are known to harbor multiple alkB genes encoding for different alkane 1-monooxygenases. In the present study, 48 Rhodococcus strains, representing 35 species of the genus, were investigated to find out whether there was a dominant type of alkB gene widespread among species of the genus that could be used as a phylogenetic marker. Phylogenetic analysis of rhodococcal alkB gene sequences indicated that a certain type of alkB gene was present in almost every member of the genus Rhodococcus. These alkB genes were common in a unique nucleotide sequence stretch absent from other types of rhodococcal alkB genes that encoded a conserved amino acid motif: WLG(I/V/L)D(G/D)GL. The sequence identity of the targeted alkB gene in Rhodococcus ranged from 78.5 to 99.2% and showed higher nucleotide sequence variation at the inter-species level compared to the 16S rRNA gene (93.9-99.8%). The results indicated that the alkB gene type investigated might be applicable for: (i) differentiating closely related Rhodococcus species, (ii) properly assigning environmental isolates to existing Rhodococcus species, and finally (iii) assessing whether a new Rhodococcus isolate represents a novel species of the genus. Copyright © 2014 Elsevier GmbH. All rights reserved.

Summary report on the aerobic degradation of diesel fuel and the degradation of toluene under aerobic, denitrifying and sulfate reducing conditions

International Nuclear Information System (INIS)

Coyne, P.; Smith, G.

1995-01-01

This report contains a number of studies that were performed to better understand the technology of the biodegradation of petroleum hydrocarbons. Topics of investigation include the following: diesel fuel degradation by Rhodococcus erythropolis; BTEX degradation by soil isolates; aerobic degradation of diesel fuel-respirometry; aerobic degradation of diesel fuel-shake culture; aerobic toluene degradation by A3; effect of HEPES, B1, and myo-inositol addition on the growth of A3; aerobic and anaerobic toluene degradation by contaminated soils; denitrifying bacteria MPNs; sulfate-reducing bacteria MPNs; and aerobic, DNB and SRB enrichments

Bioaccumulation of 137Cs by culture collection strains of bacteria and fungi

International Nuclear Information System (INIS)

Pipiska, M.; Rozloznik, M.; Augustin, J.

2003-01-01

Soil decontamination of soil contaminated by low-level activities of radionuclides, mainly by caesium-137, which come from accidental releases by maintenance of nuclear devices and by liquid wastes reprocessing, is long-term and expensive technology. Knowledge of the causations, which control the processes of bioaccumulation of radionuclides, is a necessary condition for critical assessment and successful utilization of processes of bioremediation in situ in practise. The authors present the experimentally gained quantitative values of bioaccumulation of caesium-137 from water solutions by micro organism cultures of Rhodotorula aurantiaca CCY 20-9-1, Sacharomyces cerevisiae, Rhodococcus rhodochrous ATCC 15906, Streptomyces sp. DX-IX, Coriolus versicolor CCWDF-14 and Rhizopus sp. R-18. Intensively growing cultures reach the highest values of bioaccumulation; the cultures in non-growing phase reach several orders lower values. From researched micro organisms the highest values of bioaccumulation of Cs + 5.1 pmol/g (wet weight) at initial concentration of Cs + in solution co = 1 nmol/l (without carrier) and 29.2 μmol/g (wet weight) at co = 6 mmol/l Cs + (adding of carrier CsCl) were found out at growing culture S. cerevisiae as model of eukaryotic cell after an achievement of maximal stationary grow phase. Acquired information refer to the possible role of soil micro organisms at bioaccumulation of 137 Cs in contaminated soils and their potential utilization in lowering of radioactive contamination of environment (authors)

Vanillin Catabolism in Rhodococcus jostii RHA1

Science.gov (United States)

Chen, Hao-Ping; Chow, Mindy; Liu, Chi-Chun; Lau, Alice; Liu, Jie

2012-01-01

Genes encoding vanillin dehydrogenase (vdh) and vanillate O-demethylase (vanAB) were identified in Rhodococcus jostii RHA1 using gene disruption and enzyme activities. During growth on vanillin or vanillate, vanA was highly upregulated while vdh was not. This study contributes to our understanding of lignin degradation by RHA1 and other actinomycetes. PMID:22057861

Metabolomics of the Bio-Degradation Process of Aflatoxin B1 by Actinomycetes at an Initial pH of 6.0

Directory of Open Access Journals (Sweden)

Manal Eshelli

2015-02-01

Full Text Available Contamination of food and feed by Aflatoxin B1 (AFB1 is a cause of serious economic and health problems. Different processes have been used to degrade AFB1. In this study, biological degradation of AFB1 was carried out using three Actinomycete species, Rhodococcus erythropolis ATCC 4277, Streptomyces lividans TK 24, and S. aureofaciens ATCC 10762, in liquid cultures. Biodegradation of AFB1 was optimised under a range of temperatures from 25 to 40 °C and pH values of 4.0 to 8.0. An initial concentration of 20 µg/mL of AFB1 was used in this study. The amount of AFB1 remaining was measured against time by thin layer chromatography (TLC and high-performance liquid chromatography (HPLC, coupled with UV and mass spectrometry (LC-MS. All species were able to degrade the AFB1, and no significant difference was found between them. AFB1 remained in the liquid culture for R. erythropolis, S. lividans and S. aureofaciens were 0.81 µg/mL, 2.41 µg/mL and 2.78 µg/mL respectively, at the end of the first 24 h. Degradation occurred at all incubation temperatures and the pH with the optimal conditions for R. erythropolis was achieved at 30 °C and pH 6, whereas for S. lividans and S. aureofaciens the optimum conditions for degradation were 30 °C and pH 5. Analysis of the degradative route indicated that each microorganism has a different way of degrading AFB1. The metabolites produced by R. erythropolis were significantly different from the other two microorganisms. Products of degradation were identified through metabolomic studies by utilizing high-resolution mass spectral data. Mass spectrometric analysis indicated that the degradation of AFB1 was associated with the appearance of a range of lower molecular weight compounds. The pathway of degradation or chemical alteration of AFB1 was followed by means of high resolution Fourier transform mass spectrometry (HR-FTMS analysis as well as through the MS2 fragmentation to unravel the degradative pathway for

Biodegradation of sulfamethoxazole by individual and mixed bacteria.

Science.gov (United States)

Larcher, Simone; Yargeau, Viviane

2011-07-01

Antibiotic compounds, like sulfamethoxazole (SMX), have become a concern in the aquatic environment due to the potential development of antibacterial resistances. Due to excretion and disposal, SMX has been frequently detected in wastewaters and surface waters. SMX removal in conventional wastewater treatment plants (WWTPs) ranges from 0% to 90%, and there are opposing results regarding its biodegradability at lab scale. The objective of this research was to determine the ability of pure cultures of individual and mixed consortia of bacteria (Bacillus subtilis, Pseudomonas aeruginosa, Pseudomonas putida, Rhodococcus equi, Rhodococcus erythropolis, Rhodococcus rhodocrous, and Rhodococcus zopfii) known to exist in WWTP activated sludge to remove SMX. Results showed that R. equi alone had the greatest ability to remove SMX leading to 29% removal (with glucose) and the formation of a metabolite. Degradation pathways and metabolite structures have been proposed based on the potential enzymes produced by R. equi. When R. equi was mixed with other microorganisms, a positive synergistic effect was not observed and the maximum SMX removal achieved was 5%. This indicates that pure culture results cannot be extrapolated to mixed culture conditions, and the methodology developed here to study the biodegradability of compounds under controlled mixed culture conditions offers an alternative to conventional studies using pure bacterial cultures or inocula from activated sludge sources consisting of unknown and variable microbial populations.

Biotransformation of heterocyclic dinitriles by Rhodococcus erythropolis and fungal nitrilases

Czech Academy of Sciences Publication Activity Database

Vejvoda, Vojtěch; Šveda, Ondřej; Kaplan, Ondřej; Přikrylová, Věra; Elišáková, Veronika; Himl, Michal; Kubáč, David; Pelantová, Helena; Kuzma, Marek; Křen, Vladimír; Martínková, Ludmila

2007-01-01

Roč. 29, č. 7 (2007), s. 1119-1124 ISSN 0141-5492 R&D Projects: GA AV ČR IAA500200708; GA MŠk LC06010; GA MŠk OC D25.001 Institutional research plan: CEZ:AV0Z50200510 Keywords : amidase * arpegillus nniger * heterocyclic Subject RIV: EE - Microbiology, Virology Impact factor: 1.222, year: 2007

Biotransformation of benzonitrile herbicides via the nitrile hydratase-amidase pathway in rhodococci.

Science.gov (United States)

Veselá, Alicja B; Pelantová, Helena; Sulc, Miroslav; Macková, Martina; Lovecká, Petra; Thimová, Markéta; Pasquarelli, Fabrizia; Pičmanová, Martina; Pátek, Miroslav; Bhalla, Tek Chand; Martínková, Ludmila

2012-12-01

The aim of this work was to determine the ability of rhodococci to transform 3,5-dichloro-4-hydroxybenzonitrile (chloroxynil), 3,5-dibromo-4-hydroxybenzonitrile (bromoxynil), 3,5-diiodo-4-hydroxybenzonitrile (ioxynil) and 2,6-dichlorobenzonitrile (dichlobenil); to identify the products and determine their acute toxicities. Rhodococcus erythropolis A4 and Rhodococcus rhodochrous PA-34 converted benzonitrile herbicides into amides, but only the former strain was able to hydrolyze 2,6-dichlorobenzamide into 2,6-dichlorobenzoic acid, and produced also more of the carboxylic acids from the other herbicides compared to strain PA-34. Transformation of nitriles into amides decreased acute toxicities for chloroxynil and dichlobenil, but increased them for bromoxynil and ioxynil. The amides inhibited root growth in Lactuca sativa less than the nitriles but more than the acids. The conversion of the nitrile group may be the first step in the mineralization of benzonitrile herbicides but cannot be itself considered to be a detoxification.

[Transformation of 2- and 4-cyanopyridines by free and immobilized cells of nitrile-hydrolyzing bacteria].

Science.gov (United States)

Maksimova, Iu G; Vasil'ev, D M; Ovechkina, G V; Maksimov, A Iu; Demakov, V A

2013-01-01

The transformation dynamics of 2- and 4-cyanopyridines by cells suspended and adsorbed on inorganic carriers has been studied in the Rhodococcus ruber gt 1 strain possessing nitrile hydratase activity and the Pseudomonas fluorescens C2 strain containing nitrilase. It was shown that both nitrile hydratase and nitrilase activities of immobilized cells against 2-cyanopyridine were 1.5-4 times lower compared to 4-cyanopyridine and 1.6-2 times lower than the activities of free cells against 2-cyanpopyridine. The possibility of obtaining isonicotinic acid during the combined conversion of 4-cyanopyridine by a mixed suspension of R. ruber gt 1 cells with a high level of nitrile hydratase activity and R. erythropolis 11-2 cells with a pronounced activity of amidase has been shown. Immobilization of Rhodococcus cells on raw coal and Pseudomonas cells on china clay was shown to yield a heterogeneous biocatalyst for the efficient transformation of cyanopyridines into respective amides and carbonic acids.

Secondary successions of biota in oil-polluted peat soil upon different biological remediation methods

Science.gov (United States)

Melekhina, E. N.; Markarova, M. Yu.; Shchemelinina, T. N.; Anchugova, E. M.; Kanev, V. A.

2015-06-01

The effects of different bioremediation methods on restoration of the oil-polluted peat soil (Histosol) in the northernmost taiga subzone of European Russia was studied. The population dynamics of microorganisms belonging to different trophic groups (hydrocarbon-oxidizing, ammonifying, nitrifying, and oligonitrophilic) were analyzed together with data on the soil enzyme (catalase and dehydrogenase) activities, population densities of soil microfauna groups, their structures, and states of phytocenoses during a sevenyear-long succession. The remediation with biopreparations Roder composed of oil-oxidizing microorganisms-Roder with Rhodococcus rubber and R. erythropolis and Universal with Rhodotorula glutinis and Rhodococcus sp.-was more efficient than the agrochemical and technical remediation. It was concluded that the biopreparations activate microbiological oil destruction, thereby accelerating restoration succession of phytocenosis and zoocenosis. The succession of dominant microfauna groups was observed: the dipteran larvae and Mesostigmata mites predominant at the early stages were replaced by collembolans at later stages. The pioneer oribatid mite species were Tectocepheus velatus, Oppiella nova, Liochthonius sellnicki, Oribatula tibialis, and Eupelops sp.

Fluorene transformation by bacteria of the genus Rhodococcus

NARCIS (Netherlands)

Finkelstein, Z.I.; Baskunov, B.P.; Golovlev, E.L.; Vervoort, J.J.M.; Rietjens, I.M.C.M.; Baboshin, M.A.; Golovleva, L.A.

2003-01-01

Of the four investigated Rhodococcus strains (R. rhodochrous172, R. opacus 4a and 557, and R. rhodnii 135), the first three strains were found to be able to completely transform fluorene when it was present in the medium as the sole source of carbon at a concentration of 12¿25 mg/l. At a fluorene

Rhodococcus equi Parte 2: imunologia e profilaxia Rhodococcus equi Part 2: immunology and profilaxy

Directory of Open Access Journals (Sweden)

Ana Carolina Rusca Correa Porto

2011-12-01

Full Text Available Rhodococcus equi é um patógeno ubíquo e habitante da flora intestinal dos equinos de importância na neonatologia equina. Todos os potros são expostos à doença ao nascimento, porém alguns a desenvolvem e outros não. Este artigo revisa características da resposta imune, tanto em adultos competentes quanto em potros suscetíveis ao patógeno. A resposta imune humoral é abordada, incluindo uma discussão sobre o uso do plasma hiperimune como ferramenta profilática. O papel dos mecanismos de imunidade inata na suscetibilidade de alguns potros ao R. equi é também abordado. Da mesma maneira, os componentes envolvidos na resposta cito-mediada são revisados, com atenção particular às pesquisas direcionadas ao desenvolvimento de uma vacina efetiva para ser utilizada em potros.Rhodococcus equi is an important pathogen in equine neonatology that is ubiquitous and a normal intestinal inhabitant of equines. All foals are exposed at birth, however, some foals develop disease and others do not. This article reviews concepts of the equine immune response, both in the immune adult and susceptible neonate, with respect to this pathogen. Humoral immune responses are addressed, with a discussion on the use of hyperimmune plasma as a prophylactic tool. The role that innate immune mechanisms play in the susceptibility of some foals to R. equi infection is also highlighted. Likewise, cell-mediated immune components are reviewed, with particular attention directed towards research to develop an effective vaccine for foals.

Decontamination efficiencies of pot-type water purifiers for ¹³¹I, ¹³⁴Cs and ¹³⁷Cs in rainwater contaminated during Fukushima Daiichi nuclear disaster.

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Shogo Higaki

Full Text Available Rainwater was contaminated by a large release of radionuclides into the environment during the Fukushima Daiichi nuclear disaster. It became a matter of concern for Japan when several water purification plants detected ¹³¹I contamination in the drinking water. In the present study, the decontamination efficiency of two easily obtainable commercial water purifiers were examined for rainwater contaminated with ¹³¹I, ¹³⁴Cs and ¹³⁷Cs. The water purifiers removed 94.2-97.8% of the ¹³¹I and 84.2-91.5% of the ¹³⁴Cs and ¹³⁷Cs after one filtration. Seven filtrations removed 98.2-99.6% of the ¹³¹I and over 98.0% of the ¹³⁴Cs and ¹³⁷Cs. From a practical perspective, over the fourth filtrations were not needed because of no significant improvements after the third filtration.

Microbial biodiesel production from oil palm biomass hydrolysate using marine Rhodococcus sp. YHY01.

Science.gov (United States)

Bhatia, Shashi Kant; Kim, Junyoung; Song, Hun-Seok; Kim, Hyun Joong; Jeon, Jong-Min; Sathiyanarayanan, Ganesan; Yoon, Jeong-Jun; Park, Kyungmoon; Kim, Yun-Gon; Yang, Yung-Hun

2017-06-01

The effect of various biomass derived inhibitors (i.e. furfural, hydroxymethylfurfural (HMF), vanillin, 4-hydroxy benzaldehyde (4-HB) and acetate) was investigated for fatty acid accumulation in Rhodococcus sp. YHY 01. Rhodococcus sp. YHY01 was able to utilize acetate, vanillin, and 4-HB for biomass production and fatty acid accumulation. The IC 50 value for furfural (3.1mM), HMF (3.2mM), vanillin (2.0mM), 4-HB (2.7mM) and acetate (3.7mM) was calculated. HMF and vanillin affect fatty acid composition and increase saturated fatty acid content. Rhodococcus sp. YHY 01 cultured with empty fruit bunch hydrolysate (EFBH) as the main carbon source resulted in enhanced biomass (20%) and fatty acid productivity (37%), in compression to glucose as a carbon source. Overall, this study showed the beneficial effects of inhibitory molecules on growth and fatty acid production, and support the idea of biomass hydrolysate utilization for biodiesel production by avoiding complex efforts to remove inhibitory compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biosynthesis of 1α-hydroxycorticosterone in the winter skate Leucoraja ocellata: evidence to suggest a novel steroidogenic route.

Science.gov (United States)

Wiens, J; Ho, R; Brassinga, A K; Deck, C A; Walsh, P J; Ben, R N; Mcclymont, K; Charlton, T; Evans, A N; Anderson, W G

2017-07-01

The present study explores the ability of intracellular bacteria within the renal-inter-renal tissue of the winter skate Leucoraja ocellata to metabolize steroids and contribute to the synthesis of the novel elasmobranch corticosteroid, 1α-hydroxycorticosterone (1α-OH-B). Despite the rarity of C1 hydroxylation noted in the original identification of 1α-OH-B, literature provides evidence for steroid C1 hydroxylation by micro-organisms. Eight ureolytic bacterial isolates were identified in the renal-inter-renal tissue of L. ocellata, the latter being the site of 1α-OH-B synthesis. From incubations of bacterial isolates with known amounts of potential 1α-OH-B precursors, one isolate UM008 of the genus Rhodococcus was seen to metabolize corticosteroids and produce novel products via HPLC analysis. Cations Zn 2+ and Fe 3+ altered metabolism of certain steroid precursors, suggesting inhibition of Rhodococcus steroid catabolism. Genome sequencing of UM008 identified strong sequence and structural homology to that of Rhodococcus erythropolis PR4. A complete enzymatic pathway for steroid-ring oxidation as documented within other Actinobacteria was identified within the UM008 genome. This study highlights the potential role of Rhodococcus bacteria in steroid metabolism and proposes a novel alternative pathway for 1α-OH-B synthesis, suggesting a unique form of mutualism between intracellular bacteria and their elasmobranch host. © 2017 The Fisheries Society of the British Isles.

40 CFR 98.174 - Monitoring and QA/QC requirements.

Science.gov (United States)

2010-07-01

... (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Iron and Steel Production § 98.174 Monitoring and QA/QC... moisture content of the stack gas. (5) Determine the mass rate of process feed or process production (as... Fusion Techniques (incorporated by reference, see § 98.7) for iron and ferrous scrap. (v) ASM CS-104 UNS...

Rhodococcus equi infection after alemtuzumab therapy for T-cell prolymphocytic leukemia

NARCIS (Netherlands)

Meeuse, Jan J.; Sprenger, Herman G.; Van Assen, Sander; Leduc, Dominique; Daenen, Simon M.G.J.; Arends, Jan P.; van der Werf, Tjipke

2007-01-01

Rhodococcus equi, mainly known from veterinary medicine as a pathogen in domestic animals, can also cause infections in immunocompromised humans, especially in those with defects in cellular immunity. Alemtuzumab, an anti-CD52 monoclonal antibody, causes lymphocytopenia by eliminating CD52-positive

Severe Rhodococcus equi pneumonia: case report and literature review

DEFF Research Database (Denmark)

Vestbo, Jørgen; Lundgren, Jens Dilling; Gaub, J

1991-01-01

or sputum on standard media, but is frequently regarded as a contaminant. Mortality from Rhodococcus equi pneumonia is high (25%) and early surgical intervention has been recommended. Based on this review, the benefit of surgery seems dubious, whereas good results have been obtained using long......-term antibiotic treatment with erythromycin plus rifampicin, or vancomycin in combination with either of these antibiotics....

SEPARATION OF CsCl FROM LiCl-CsCl MOLTEN SALT BY COLD FINGER MELT CRYSTALLIZATION

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JOSHUA R. VERSEY

2014-06-01

Full Text Available This study provides a fundamental understanding of a cold finger melt crystallization technique by exploring the heat and mass transfer processes of cold finger separation. A series of experiments were performed using a simplified LiCl-CsCl system by varying initial CsCl concentrations (1, 3, 5, and 7.5 wt%, cold finger cooling rates (7.4, 9.8, 12.3, and 14.9 L/min, and separation times (5, 10, 15, and 30 min. Results showed a potential recycling rate of 0.36 g/min with a purity of 0.33 wt% CsCl in LiCl. A CsCl concentrated drip formation was found to decrease crystal purity especially for smaller crystal formations. Dimensionless heat and mass transfer correlations showed that separation production is primarily influenced by convective transfer controlled by cooling gas flow rate, where correlations are more accurate for slower cooling gas flow rates.

Seperation of CsCl from LiCl-CsCl molten salt by cold finger melt cryst allization

Energy Technology Data Exchange (ETDEWEB)

Versey, Joshua R. [Dept. of Chemical and Materials Engineering and Nuclear Engineering Program University of Idaho, Idaho (United States); Phongikaroon, Supathorn [Dept. of Mechanical and Nuclear Engineering Virginia Commonwealth University, Richmond (Korea, Republic of); Simpson, Michael F. [Dept. of Metallurgical Engineering University of Utah, Utah (Korea, Republic of)

2014-06-15

This study provides a fundamental understanding of a cold finger melt crystallization technique by exploring the heat and mass transfer processes of cold finger separation. A series of experiments were performed using a simplified LiCl-CsCl system by varying initial CsCl concentrations (1, 3, 5, and 7.5 wt%), cold finger cooling rates (7.4, 9.8, 12.3, and 14.9 L/min), and separation times (5, 10, 15, and 30 min). Results showed a potential recycling rate of 0.36 g/min with a purity of 0.33 wt% CsCl in LiCl. A CsCl concentrated drip formation was found to decrease crystal purity especially for smaller crystal formations. Dimensionless heat and mass transfer correlations showed that separation production is primarily influenced by convective transfer controlled by cooling gas flow rate, where correlations are more accurate for slower cooling gas flow rates.

Cloning, expression, and enzymatic activity evaluation of cholesterol oxidase gene isolated from a native Rhodococcus sp.

Directory of Open Access Journals (Sweden)

Hamed Esmaeil Lashgarian

2016-10-01

Full Text Available Cholesterol oxidase (CHO is one of the valuable enzymes that play an important role in: measurement of serum cholesterol, food industry as a biocatalyst and agriculture as a biological larvicide. This enzyme was produced by several bacterial strains. Wild type enzyme produced by Rhodococcus sp. secret two forms of CHO enzyme: extra cellular and membrane bound type which its amount is low and unstable. The goal of the study was cloning, expression, and enzymatic activity evaluation of cholesterol oxidase gene isolated from a native Rhodococcus sp. CHO gene was isolated from native bacteria and cloned into pET23a. In the next step, the construct was expressed in E.coli BL21 and induced by different concentration of IPTG ranges from 0.1 - 0.9 mM. This gene contains 1642 bp and encodes a protein consists of 533 amino acids. It has about 96 % homology with CHO gene isolated from Rhodococcus equi. The high expression was obtained in 0.5 mM concentration of IPTG after 4 hour induction. This recombinant enzyme had a molecular weight of 55 kDa, that secretion of intra cellular type is much more than extracellular form. The optimum pH and temperature conditions for the recombinant enzyme were 7.5 and 45°C, respectively. CHO enzyme obtained from Rhodococcus sp. is a cheap enzyme with medical and industrial applications that can be produced easily and purified in large scale with simple methods.

[Respiratory infections caused by slow-growing bacteria: Nocardia, Actinomyces, Rhodococcus].

Science.gov (United States)

Eschapasse, E; Hussenet, C; Bergeron, A; Lebeaux, D

2017-06-01

Pneumonia caused by slow-growing bacteria is rare but sometimes severe. These infections share many similarities such as several differential diagnoses, difficulties to identify the pathogen, the importance of involving the microbiologist in the diagnostic investigation and the need for prolonged antibiotic treatment. However, major differences distinguish them: Nocardia and Rhodococcus infect mainly immunocompromised patients while actinomycosis also concerns immunocompetent patients; the severity of nocardioses is related to their hematogenous spread while locoregional extension by contiguity makes the gravity of actinomycosis. For these diseases, molecular diagnostic tools are essential, either to obtain a species identification and guide treatment in the case of nocardiosis or to confirm the diagnosis from a biological sample. Treatment of these infections is complex due to: (1) the limited data in the literature; (2) the need for prolonged treatment of several months; (3) the management of toxicities and drug interactions for the treatment of Nocardia and Rhodococcus. Close cooperation between pneumonologists, infectious disease specialists and microbiologists is essential for the management of these patients. Copyright © 2017 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Effect of Tween 80 on 9a-steroid hydroxylating activity and ultrastructural characteristics of Rhodococcus sp. cells

OpenAIRE

Avramova , Tatyana; Spassova , Dimitrina; Mutafov , Sava; Momchilova , Svetlana; Boyadjieva , Lilyana; Damyanova , Boryana; Angelova , Blaga

2010-01-01

International audience; Studied is the effect of the non-ionic surfactant Tween 80 on the microbial transformation of 4-androstene- 3,17-dione into its 9a-hydroxy-derivative by resting Rhodococcus sp. cells. The surfactant was applied in the cultivation medium as an additional source of carbon, in the transformation reaction medium as a mediator of the steroid substrate solubility or was used for permeabilization of the glucose grown Rhodococcus sp. cells. Special attention is paid to the fac...

Potential of Rhodococcus strains for biotechnological vanillin production from ferulic acid and eugenol.

Science.gov (United States)

Plaggenborg, Rainer; Overhage, Jörg; Loos, Andrea; Archer, John A C; Lessard, Philip; Sinskey, Anthony J; Steinbüchel, Alexander; Priefert, Horst

2006-10-01

The potential of two Rhodococcus strains for biotechnological vanillin production from ferulic acid and eugenol was investigated. Genome sequence data of Rhodococcus sp. I24 suggested a coenzyme A-dependent, non-beta-oxidative pathway for ferulic acid bioconversion, which involves feruloyl-CoA synthetase (Fcs), enoyl-CoA hydratase/aldolase (Ech), and vanillin dehydrogenase (Vdh). This pathway was proven for Rhodococcus opacus PD630 by physiological characterization of knockout mutants. However, expression and functional characterization of corresponding structural genes from I24 suggested that degradation of ferulic acid in this strain proceeds via a beta-oxidative pathway. The vanillin precursor eugenol facilitated growth of I24 but not of PD630. Coniferyl aldehyde was an intermediate of eugenol degradation by I24. Since the genome sequence of I24 is devoid of eugenol hydroxylase homologous genes (ehyAB), eugenol bioconversion is most probably initiated by a new step in this bacterium. To establish eugenol bioconversion in PD630, the vanillyl alcohol oxidase gene (vaoA) from Penicillium simplicissimum CBS 170.90 was expressed in PD630 together with coniferyl alcohol dehydrogenase (calA) and coniferyl aldehyde dehydrogenase (calB) genes from Pseudomonas sp. HR199. The recombinant strain converted eugenol to ferulic acid. The obtained data suggest that genetically engineered strains of I24 and PD630 are suitable candidates for vanillin production from eugenol.

Pneumonia por Rhodococcus equi em doente VIH (+: A propósito de uma associação rara

Directory of Open Access Journals (Sweden)

Paula Esteves

2007-09-01

Full Text Available Resumo: A infecção humana por Rhodococcus equi, mesmo no contexto da infecção pelo VIH, é relativamente rara. Os autores apresentam o caso clínico de um indivíduo, infectado pelo VIH, que apresentava um quadro clínico e imagiológico compatível com pneumonia, cujos exames iniciais revelaram a presença de Pneumocystis jiroveci. Após realização de terapêutica específica, perante a manutenção do quadro clínico-imagiológico, procedeu-se à realização de novos exames complementares, tendo sido identificado a presença de Rhodococcus equi no lavado broncoalveolar. Com instituição de terapêutica dirigida a este agente, verificou--se progressiva melhoria clínica e imagiológica. Os autores efectuam uma revisão bibliográfica da pneumonia por Rhodococcus equi, salientando a raridade desta associação e a elevada sobrevida observada. Abstract: The human infection by Rhodococcus equi, even in the presence of HIV infection, remains a rare disease. The authors present a case report of pneumonia, occurring in a HIV (+ man. After identifying Pneumocystis jiroveci in the BAL, despite proper medication, the patient didn’t improve. Another BAL was performed and a Rhodoccus equi isolated. The therapeutic regimen was changed according to this finding and the patient improved. The authors make a review of the literature, focusing on the rarity of this association and the high survival observed. Palavras-chave: Rhodococcus equi, Pneumocystis jiroveci, VIH, Key-words: Rhodococcus equi, Pneumocystis jiroveci, HIV

Genome-based exploration of the specialized metabolic capacities of the genus Rhodococcus

NARCIS (Netherlands)

Ceniceros, Ana; Dijkhuizen, Lubbert; Petrusma, Mirjan; Medema, M.H.

2017-01-01

Background Bacteria of the genus Rhodococcus are well known for their ability to degrade a large range of organic compounds. Some rhodococci are free-living, saprophytic bacteria; others are animal and plant pathogens. Recently, several studies have shown that their genomes encode putative pathways

Genome-based exploration of the specialized metabolic capacities of the genus Rhodococcus

NARCIS (Netherlands)

Ceniceros, Ana; Dijkhuizen, Lubbert; Petrusma, Mirjan; Medema, Marnix H.

2017-01-01

Background: Bacteria of the genus Rhodococcus are well known for their ability to degrade a large range of organic compounds. Some rhodococci are free-living, saprophytic bacteria; others are animal and plant pathogens. Recently, several studies have shown that their genomes encode putative pathways

Genome-based exploration of the specialized metabolic capacities of the genus Rhodococcus

NARCIS (Netherlands)

Ceniceros, Ana; Dijkhuizen, Lubbert; Petrusma, Mirjan; Medema, Marnix H

2017-01-01

BACKGROUND: Bacteria of the genus Rhodococcus are well known for their ability to degrade a large range of organic compounds. Some rhodococci are free-living, saprophytic bacteria; others are animal and plant pathogens. Recently, several studies have shown that their genomes encode putative pathways

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.

Bacteremia due to Rhodococcus equi in an immunocompetent infant

OpenAIRE

P Devi; S Malhotra; A Chadha

2011-01-01

Rhodococcus equi , previously known as Corynebacterium equi, is one of the most important causes of zoonotic infection in grazing animals. Increased cases of human infection with R. equi have been reported especially in immunocompromised patients. Infection in immunocompetent patients is extremely rare. We report a case of R. equi bacteremia in a 26-day-old immunocompetent infant with recurrent swellings on different parts of the body. To the best of our knowledge, this is the first ever repo...

Disseminated Rhodococcus equi infection in a kidney transplant patient without initial pulmonary involvement

NARCIS (Netherlands)

Rahamat-Langendoen, Janette C.; van Meurs, Matijs; Zijlstra, Jan G.; Lo-Ten-Foe, Jerome R.

2009-01-01

Rhodococcus equi is increasingly recognized as an opportunistic pathogen in solid organ transplant recipients. Primary pulmonary involvement is the most common finding. We report a case of a 42-year-old female kidney transplant recipient who developed multiple disseminated abscesses caused by R.

Biodegradation of cyanide by acetonitrile-induced cells of Rhodococcus sp. UKMP-5M.

Science.gov (United States)

Nallapan Maniyam, Maegala; Sjahrir, Fridelina; Ibrahim, Abdul Latif; Cass, Anthony E G

2013-01-01

A Rhodococcus sp. UKMP-5M isolate was shown to detoxify cyanide successfully, suggesting the presence of an intrinsic property in the bacterium which required no prior cyanide exposure for induction of this property. However, in order to promote growth, Rhodococcus sp. UKMP-5M was fully acclimatized to cyanide after 7 successive subcultures in 0.1 mM KCN for 30 days. To further shorten the lag phase and simultaneously increase the tolerance towards higher cyanide concentrations, the bacterium was induced with various nitrile compounds sharing a similar degradatory pathway to cyanide. Acetonitrile emerged as the most favored inducer and the induced cells were able to degrade 0.1 mM KCN almost completely within 18 h. With the addition of subsequent aliquots of 0.1 mM KCN a shorter period for complete removal of cyanide was required, which proved to be advantageous economically. Both resting cells and crude enzyme of Rhodococcus sp. UKMP-5M were able to biodegrade cyanide to ammonia and formate without the formation of formamide, implying the identification of a simple hydrolytic cyanide degradation pathway involving the enzyme cyanidase. Further verification with SDS-PAGE revealed that the molecular weight of the active enzyme was estimated to be 38 kDa, which is consistent with previously reported cyanidases. Since the recent advancement in the application of biological methods in treating cyanide-bearing wastewater has been promising, the discovery of this new bacterium will add value by diversifying the existing microbial populations capable of cyanide detoxification.

Infecção por Rhodococcus em doente imunocompetente - a propósito de um caso

Directory of Open Access Journals (Sweden)

Susana Barbosa

2015-12-01

Full Text Available Resumo: O Rhodococcus equi raramente causa infecção no humano, sendo que a maioria dos casos descritos estão associados a doentes imunodeprimidos. Os autores apresentam o caso de um homem de 65 anos que foi admitido no serviço de urgência por agravamento da dispneia habitual, tosse e febre. Foi internado com o diagnóstico de sépsis com ponto de partida respiratório em pneumonia de focos múltiplos e peritonite. Medicado empiricamente com ceftriaxone, com melhoria clínica. Isolamento no líquido ascítico de Rhodococcus spp. Cumpriu 2 meses de antibioterapia com doxiciclina, com boa evolução clínica, analítica e radiológica. Os autores apresentam este caso dada a raridade da situação e pretendem realçar a necessidade de um elevado índice de suspeição para o diagnóstico da infecção por este agente em doentes imunocompetentes. Abstract: Rhodococcus equi rarely causes human infection, and most of the described cases are associated with immunosuppressed patients. The authors present a 65-year-old man who was admitted to the emergency department with worsening of dyspnoea, cough and fever. He was admitted with a diagnosis of sepsis with respiratory starting point in multiple foci pneumonia and peritonitis. He was medicated empirically with ceftriaxone, with clinical improvement. Isolation in the ascites fluid of Rhodococcus spp. He completed two months of antibiotic treatment with doxycycline, with clinical, analytical and radiological improvement. The authors present this case due to the rarity of the situation and highlight the need for a high index of suspicion for the infection diagnosis by this agent in immunocompetent patients.

Biodegradation of dimethyl phthalate, diethyl phthalate and di-n-butyl phthalate by Rhodococcus sp. L4 isolated from activated sludge.

Science.gov (United States)

Lu, Yi; Tang, Fei; Wang, Ying; Zhao, Jinhui; Zeng, Xin; Luo, Qifang; Wang, Lin

2009-09-15

In this study, an aerobic bacterial strain capable of utilizing dimethyl phthalate (DMP), diethyl phthalate (DEP) and di-n-butyl phthalate (DBP) as sole carbon source and energy was isolated from activated sludge collected from a dyeing plant. According to its morphology, physiochemical characteristics and 16S rDNA sequence, the strain was identified as Rhodococcus ruber. The biodegradation batch tests of DMP, DEP and DBP by the Rhodococcus sp. L4 showed the optimal pH value, temperature and substrate concentration: pH 7.0-8.0, 30-37 degrees C and PAEs concentration Kinetics of degradation have also been performed at different initial concentrations. The results show that the degradation can be described with exponential model. The half-life of degradation was about 1.30 days when the concentration of PAEs mixture was lower than 300 mg/L. PAEs contaminated water samples (300 mg/L) with non-emulsification and completed emulsification were prepared to investigate the effect on PAEs degradation rate. Little difference between the above two sample preparations was observed in terms of ultimate degradation rate. Rhodococcus sp. L4 can also grow on phenol, sodium benzoate or naphthalene solution as sole carbon source and energy which suggests its ability in resisting environmental toxicants. This work provides some new evidence for the possibility of applying Rhodococcus for contaminated water remediation in the area of industry.

Biosurfactant production by halotolerant Rhodococcus fascians from Casey Station, Wilkes Land, Antarctica.

Science.gov (United States)

Gesheva, Victoria; Stackebrandt, Erko; Vasileva-Tonkova, Evgenia

2010-08-01

Isolate A-3 from Antarctic soil in Casey Station, Wilkes Land, was characterized for growth on hydrocarbons. Use of glucose or kerosene as a sole carbon source in the culture medium favoured biosynthesis of surfactant which, by thin-layer chromatography, indicated the formation of a rhamnose-containing glycolipid. This compound lowered the surface tension at the air/water interface to 27 mN/m as well as inhibited the growth of B. subtilis ATCC 6633 and exhibited hemolytic activity. A highly hydrophobic surface of the cells suggests that uptake occurs via a direct cell-hydrocarbon substrate contact. Strain A-3 is Gram-positive, halotolerant, catalase positive, urease negative and has rod-coccus shape. Its cell walls contained meso-diaminopimelic acid. Phylogenetic analysis based on comparative analysis of 16S rRNA gene sequences revealed that strain A-3 is closely related to Rhodococcus fascians with which it shares 100% sequence similarity. This is the first report on rhamnose-containing biosurfactant production by Rhodococcus fascians isolated from Antarctic soil.

MICs of Oxazolidinones for Rhodococcus equi Strains Isolated from Humans and Animals

OpenAIRE

Bowersock, Terry L.; Salmon, Sarah A.; Portis, Ellen S.; Prescott, John F.; Robison, Denise A.; Ford, Charles W.; Watts, Jeffrey L.

2000-01-01

Eperezolid and linezolid are representatives of a new class of orally active, synthetic antimicrobial agents. The in vitro activity values (MICs) of linezolid, eperezolid, and comparator antibiotics against 102 strains of Rhodococcus equi isolated from humans and animals were determined. Linezolid was more active than eperezolid against the strains tested; premafloxacin was the most active comparator antibiotic.

Enzyme-substrate binding landscapes in the process of nitrile biodegradation mediated by nitrile hydratase and amidase.

Science.gov (United States)

Zhang, Yu; Zeng, Zhuotong; Zeng, Guangming; Liu, Xuanming; Chen, Ming; Liu, Lifeng; Liu, Zhifeng; Xie, Gengxin

2013-08-01

The continuing discharge of nitriles in various industrial processes has caused serious environmental consequences of nitrile pollution. Microorganisms possess several nitrile-degrading pathways by direct interactions of nitriles with nitrile-degrading enzymes. However, these interactions are largely unknown and difficult to experimentally determine but important for interpretation of nitrile metabolisms and design of nitrile-degrading enzymes with better nitrile-converting activity. Here, we undertook a molecular modeling study of enzyme-substrate binding modes in the bi-enzyme pathway for degradation of nitrile to acid. Docking results showed that the top substrates having favorable interactions with nitrile hydratase from Rhodococcus erythropolis AJ270 (ReNHase), nitrile hydratase from Pseudonocardia thermophila JCM 3095 (PtNHase), and amidase from Rhodococcus sp. N-771 (RhAmidase) were benzonitrile, 3-cyanopyridine, and L-methioninamide, respectively. We further analyzed the interactional profiles of these top poses with corresponding enzymes, showing that specific residues within the enzyme's binding pockets formed diverse contacts with substrates. This information on binding landscapes and interactional profiles is of great importance for the design of nitrile-degrading enzyme mutants with better oxidation activity toward nitriles or amides in the process of pollutant treatments.

Kinetics of hydrocarbon extraction from oil shale using biosurfactant producing bacteria

International Nuclear Information System (INIS)

Haddadin, Malik S.Y.; Abou Arqoub, Ansam A.; Abu Reesh, Ibrahim; Haddadin, Jamal

2009-01-01

This study was done to extract hydrocarbon compounds from El-Lajjun oil shale using biosurfactant produced from two strains Rhodococcus erythropolis and Rhodococcus ruber. The results have shown that, optimal biosurfactant production was found using naphthalene and diesel as a carbon source for R. erthropolis and R. ruber, respectively. Optimum nitrogen concentration was 9 g/l and 7 g/l for R. erthropolis and R. ruber, respectively. Optimum K 2 HPO 4 to KH 2 PO 4 ratio, temperature, pH, and agitation speeds were 2:1, 37 deg. C, 7 and 200 rpm. Under optimal conditions R. erthropolis and R. ruber produced 5.67 and 6.9 g/l biosurfactant, respectively. Maximum recovery of oil achieved with hydrogen peroxide pre-treatment was 25% and 26% at biosurfactant concentration of 8 g/l and 4 g/l for R. erthropolis and R. ruber, respectively. The extent desorption of hydrocarbons from the pre-treated oil shale by biosurfactant were inversely related to the concentration of high molecular weight hydrocarbons, asphaltenes compounds. Pre- treatment of oil shale with hydrogen peroxide produced better improvement in aromatic compounds extraction in comparison with improvement which resulted from demineralization of the oil shale

A new zearalenone biodegradation strategy using non-pathogenic Rhodococcus pyridinivorans K408 strain.

Science.gov (United States)

Kriszt, Rókus; Krifaton, Csilla; Szoboszlay, Sándor; Cserháti, Mátyás; Kriszt, Balázs; Kukolya, József; Czéh, Arpád; Fehér-Tóth, Szilvia; Török, Lívia; Szőke, Zsuzsanna; Kovács, Krisztina J; Barna, Teréz; Ferenczi, Szilamér

2012-01-01

Zearalenone (hereafter referred to as ZEA) is a nonsteroidal estrogenic mycotoxin produced by several Fusarium spp. on cereal grains. ZEA is one of the most hazardous natural endocrine disrupting chemicals (EDC) which induces hyper estrogenic responses in mammals. This can result in reproductive disorders in farm animals as well as in humans. Consequently, detoxification strategies for contaminated crops are crucial for food safety. In this study we have developed a bacterial based detoxification system using a non-pathogen Rhodococcus pyridinivorans K408 strain. Following 5 days treatment of ZEA with R. pyridinivorans K408 strain HPLC analyses showed an 87.21% ZEA-degradation efficiency of the bacterial enzyme systems. In another approach, the strain biotransformation ability has also been confirmed by a bioluminescent version of the yeast estrogen screening system (BLYES), which detected an 81.75% of biodegradability of ZEA, in a good agreement with the chemical analyses. Furthermore, the capacity of R. pyridinivorans to eliminate the estrogenic effects of ZEA was tested by using an immature uterotrophic assay. Prepubertal female rats were treated with vehicle (olive oil), 17β-estradiol, ZEA (0.1-1-5-10 mg/kg body weight) and LB broth containing 500 mg/l ZEA that has already been incubated with or without Rhodococcus pyridinivorans K408 strain. Uterine weights were measured and the mRNA level changes relating to apelin, aquaporin 5, complement component 2, and calbindin-3 genes were measured by qRT-PCR. These genes represent the major pathways that are affected by estromimetic compounds. Zearalenone feeding significantly increased the uterus weight in a dose dependent manner and at the same time upregulated complement component 2 and calbindin-3 expression as well as decreased apelin and aquaporin 5 mRNA levels comparable to that seen in 17β-estradiol exposed rats. In contrast, LB broth in which ZEA was incubated with Rhodococcus pyridinivorans K408 prior to

A new zearalenone biodegradation strategy using non-pathogenic Rhodococcus pyridinivorans K408 strain.

Directory of Open Access Journals (Sweden)

Rókus Kriszt

Full Text Available Zearalenone (hereafter referred to as ZEA is a nonsteroidal estrogenic mycotoxin produced by several Fusarium spp. on cereal grains. ZEA is one of the most hazardous natural endocrine disrupting chemicals (EDC which induces hyper estrogenic responses in mammals. This can result in reproductive disorders in farm animals as well as in humans. Consequently, detoxification strategies for contaminated crops are crucial for food safety. In this study we have developed a bacterial based detoxification system using a non-pathogen Rhodococcus pyridinivorans K408 strain. Following 5 days treatment of ZEA with R. pyridinivorans K408 strain HPLC analyses showed an 87.21% ZEA-degradation efficiency of the bacterial enzyme systems. In another approach, the strain biotransformation ability has also been confirmed by a bioluminescent version of the yeast estrogen screening system (BLYES, which detected an 81.75% of biodegradability of ZEA, in a good agreement with the chemical analyses. Furthermore, the capacity of R. pyridinivorans to eliminate the estrogenic effects of ZEA was tested by using an immature uterotrophic assay. Prepubertal female rats were treated with vehicle (olive oil, 17β-estradiol, ZEA (0.1-1-5-10 mg/kg body weight and LB broth containing 500 mg/l ZEA that has already been incubated with or without Rhodococcus pyridinivorans K408 strain. Uterine weights were measured and the mRNA level changes relating to apelin, aquaporin 5, complement component 2, and calbindin-3 genes were measured by qRT-PCR. These genes represent the major pathways that are affected by estromimetic compounds. Zearalenone feeding significantly increased the uterus weight in a dose dependent manner and at the same time upregulated complement component 2 and calbindin-3 expression as well as decreased apelin and aquaporin 5 mRNA levels comparable to that seen in 17β-estradiol exposed rats. In contrast, LB broth in which ZEA was incubated with Rhodococcus pyridinivorans K

A high-throughput screening strategy for nitrile-hydrolyzing enzymes based on ferric hydroxamate spectrophotometry.

Science.gov (United States)

He, Yu-Cai; Ma, Cui-Luan; Xu, Jian-He; Zhou, Li

2011-02-01

Nitrile-hydrolyzing enzymes (nitrilase or nitrile hydratase/amidase) have been widely used in the pharmaceutical industry for the production of carboxylic acids and their derivatives, and it is important to build a method for screening for nitrile-hydrolyzing enzymes. In this paper, a simple, rapid, and high-throughput screening method based on the ferric hydroxamate spectrophotometry has been proposed. To validate the accuracy of this screening strategy, the nitrilases from Rhodococcus erythropolis CGMCC 1.2362 and Alcaligenes sp. ECU0401 were used for evaluating the method. As a result, the accuracy for assaying aliphatic and aromatic carboxylic acids was as high as the HPLC-based method. Therefore, the method may be potentially used in the selection of microorganisms or engineered proteins with nitrile-hydrolyzing enzymes.

Discovery and characterization of thermophilic limonene-1,2-epoxide hydrolases from hot spring metagenomic libraries

DEFF Research Database (Denmark)

Ferrandi, Erica Elisa; Sayer, Christopher; Isupov, Michail N.

2015-01-01

thermophilic sources, have higher optimal temperatures and apparent melting temperatures than Re-LEH. The new LEH enzymes have been crystallized and their structures solved to high resolution in the native form and in complex with the inhibitor valpromide for Tomsk-LEH and poly(ethylene glycol) for CH55-LEH......,2-epoxide hydrolase (LEH) family of enzymes. These two LEHs (Tomsk-LEH and CH55-LEH) show EH activities towards different epoxide substrates, differing in most cases from those previously identified for Rhodococcus erythropolis (Re-LEH) in terms of stereoselectivity. Tomsk-LEH and CH55-LEH, both from....... The structural analysis has provided insights into the LEH mechanism, substrate specificity and stereoselectivity of these new LEH enzymes, which has been supported by mutagenesis studies....

Bacteremia due to Rhodococcus equi in an immunocompetent infant

Directory of Open Access Journals (Sweden)

P Devi

2011-01-01

Full Text Available Rhodococcus equi , previously known as Corynebacterium equi, is one of the most important causes of zoonotic infection in grazing animals. Increased cases of human infection with R. equi have been reported especially in immunocompromised patients. Infection in immunocompetent patients is extremely rare. We report a case of R. equi bacteremia in a 26-day-old immunocompetent infant with recurrent swellings on different parts of the body. To the best of our knowledge, this is the first ever report of R. equi bacteremia from an immunocompetent patient from Northern India.

Complete Genome Sequence of Rhodococcus sp. Strain WMMA185, a Marine Sponge-Associated Bacterium

OpenAIRE

Adnani, Navid; Braun, Doug R.; McDonald, Bradon R.; Chevrette, Marc G.; Currie, Cameron R.; Bugni, Tim S.

2016-01-01

The Rhodococcus strain WMMA185 was isolated from the marine sponge Chondrilla nucula as part of ongoing drug discovery efforts. Analysis of the 4.44-Mb genome provides information regarding interspecies interactions as pertains to regulation of secondary metabolism and natural product biosynthetic potentials.

Analysis of genome sequences from plant pathogenic Rhodococcus reveals genetic novelties in virulence loci

Science.gov (United States)

Members of Gram-positive Actinobacteria cause economically important diseases to plants. Within the Rhodococcus genus, some members can cause growth deformities and persist as pathogens on a wide range of host plants. The current model predicts that phytopathogenic isolates require a cluster of thre...

Cold adaptive traits revealed by comparative genomic analysis of the eurypsychrophile Rhodococcus sp. JG3 isolated from high elevation McMurdo Dry Valley permafrost, Antarctica.

Science.gov (United States)

Goordial, Jacqueline; Raymond-Bouchard, Isabelle; Zolotarov, Yevgen; de Bethencourt, Luis; Ronholm, Jennifer; Shapiro, Nicole; Woyke, Tanja; Stromvik, Martina; Greer, Charles W; Bakermans, Corien; Whyte, Lyle

2016-02-01

The permafrost soils of the high elevation McMurdo Dry Valleys are the most cold, desiccating and oligotrophic on Earth. Rhodococcus sp. JG3 is one of very few bacterial isolates from Antarctic Dry Valley permafrost, and displays subzero growth down to -5°C. To understand how Rhodococcus sp. JG3 is able to survive extreme permafrost conditions and be metabolically active at subzero temperatures, we sequenced its genome and compared it to the genomes of 14 mesophilic rhodococci. Rhodococcus sp. JG3 possessed a higher copy number of genes for general stress response, UV protection and protection from cold shock, osmotic stress and oxidative stress. We characterized genome wide molecular adaptations to cold, and identified genes that had amino acid compositions favourable for increased flexibility and functionality at low temperatures. Rhodococcus sp. JG3 possesses multiple complimentary strategies which may enable its survival in some of the harshest permafrost on Earth. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Infecção pulmonar por "Rhodococcus equi": relato dos dois primeiros casos brasileiros Pulmonary Rhodococcus equi infection: report of the first two Brazilian cases

Directory of Open Access Journals (Sweden)

LUIZ CARLOS SEVERO

2001-05-01

Full Text Available O Rhodococcus equi, principal agente da rodococose, é um cocobacilo pleomórfico, gram-positivo e aeróbio, que infecta humanos por via inalatória ou transcutânea e se manifesta clinicamente como abscesso pulmonar. Relatam-se os dois primeiros casos brasileiros da doença. Ambos os pacientes eram imunocomprometidos e apresentavam quadro infeccioso pulmonar. O primeiro tinha AIDS e apresentava pneumonia cavitada em lobo superior esquerdo, que teve evolução fatal. O segundo tinha doença de Goodpasture, insuficiência renal crônica e fazia uso de corticosteróides. Apresentava uma lesão pulmonar escavada no lobo superior direito, que foi tratada com sulfametoxazol-trimetoprim, com resolução do processo.Rhodococcus equi, the principal agent of rhodococcosis, is a pleomorphic, gram-positive, aerobic coccus bacillus that infects humans by inhalation or through a transcutaneous route. It is clinically manifested as a pulmonary abscess. The first two Brazilian cases of rhodococcosis are reported on. Both patients were immunocompromised and showed pulmonary infection. The first patient had AIDS and cavitating pneumonia in the left upper lobe, that was fatal. The second case presented Goodpasture syndrome and was under chronic corticotherapy. He displayed a cavitating nodular lesion in the right upper lobe, that was successfully treated with sulfametoxazol-trimethoprim.

Theoretical study of the Cs isotope exchange reaction of CsI + Cs' → Cs + ICs' (Contract research)

International Nuclear Information System (INIS)

Kobayashi, Takanori; Hashimoto, Masashi; Yokoyama, Keiichi

2015-12-01

To discuss the exchange reaction of Cs isotope by CsI + Cs' → Cs + ICs', the structure and chemical properties of Cs 2 I intermediate and potential energy surface of the entrance reaction are calculated using M06/def2-TZVPPD density functional calculation. The calculation shows that the reaction to the intermediate has no barrier and the two Cs-I bonds of Cs 2 I are chemically equivalent. These results suggest that the rate of the Cs exchange reaction of CsI + Cs' → Cs + ICs' is as high as the collision rate. (author)

Biotransformation of d-Limonene to (+) trans-Carveol by Toluene-Grown Rhodococcus opacus PWD4 Cells

Science.gov (United States)

Duetz, Wouter A.; Fjällman, Ann H. M.; Ren, Shuyu; Jourdat, Catherine; Witholt, Bernard

2001-01-01

The toluene-degrading strain Rhodococcus opacus PWD4 was found to hydroxylate d-limonene exclusively in the 6-position, yielding enantiomerically pure (+) trans-carveol and traces of (+) carvone. This biotransformation was studied using cells cultivated in chemostat culture with toluene as a carbon and energy source. The maximal specific activity of (+) trans-carveol formation was 14.7 U (g of cells [dry weight])−1, and the final yield was 94 to 97%. Toluene was found to be a strong competitive inhibitor of the d-limonene conversion. Glucose-grown cells did not form any trans-carveol from d-limonene. These results suggest that one of the enzymes involved in toluene degradation is responsible for this allylic monohydroxylation. Another toluene degrader (Rhodococcus globerulus PWD8) had a lower specific activity but was found to oxidize most of the formed trans-carveol to (+) carvone, allowing for the biocatalytic production of this flavor compound. PMID:11375201

Enhancement of dibenzothiophene biodesulfurization using {beta}-cyclodextrins in oil-to-water media

Energy Technology Data Exchange (ETDEWEB)

Ainhoa Caro; Pedro Leton; Eloy Garcia-Calvo; Leonardo Setti [Universidad de Alcala, Madrid (Spain). Departamento de Quimica Analitica e Ingeniera Quimica

2007-11-15

It has been reported that biodesulfurization (BDS) of dibenzothiophene (DBT) in oil-to-water emulsions is carried out by growing cells of the aerobic Rhodococcus erythropolis IGTS8 strain and developing the so-called 4S desulfurization pathway. On adding {beta}-cyclodextrins, it is possible to improve the BDS yields, increase the diffusion of DBT into the aqueous phase or avoid the HBP accumulation. Moreover, by using greater biocatalyst initial concentrations and adding 15 ppm of {beta}-cyclodextrin, a very high BDS yield has been observed, but the presence of mass transfer limitations and the inhibition effects were not satisfactorily avoided. The Haldane kinetic model agreed well with the experimental results obtained, and the values of the kinetic parameters were determined. Short communication. 20 refs., 2 figs., 2 tabs.

In vitro and in vivo efficiency of clinoptilolite in 137Cs binding

International Nuclear Information System (INIS)

Vitorovic, D.; Vitorovic, G.; Mladenovic, V.; Vukicevic, O.

1998-01-01

The results of investigation of the sorption of micro amounts of 137 Cs on powdered clinoptilolite in an electrolyte similar to the stomach content of animals are presented. The experiments were performed with the natural form of clinoptilolite from the Zlatopek mine (Vranjska Banja) and with the sodium form at 37 deg C. Simultaneously, investigation was made into the efficiency of the natural form of clinoptilolite in the radioprotection of chicks alimentary contaminated with 1 37 Cs. Clinoptilolite showed a high efficiency in 137 Cs sorption from the electrolyte solution, where 96-98% of initial activity was sorbed. Protection effect in chicks alimentary contaminated with 137 Cs, measured 3 and 7 hours after the contamination, was approximately 75% for the meat and edible inner organs of the chicks

The selective separation of Cs and Sr ion on the inorganic ion-exchanger zeolites

Energy Technology Data Exchange (ETDEWEB)

Park, Hun Hwee; Min, Byeog Heon [Hoseo University, Taegu (Korea)

1998-04-01

This study shows the selective separation of Cs and Sr ion on the inorganic ion-exchanger zeolites such as clinoptilolite, Y-type CBV760, CBV780 and A-type 3A. The selective separation of Cs and Sr on these zeolites was examined using batch and continuous column experiments. For the selective separation of Cs and Sr from a synthetic wastewater, adsorption rate of Cs increased in the order, clinoptilolite> 3A>> CBV760> CBV780, adsorption rate of Sr increased in the other, 3A>> clinoptilolite> CBV760> CBV780. For the clinoptilolite, the adsorption rate of Cs reached about 96 {approx} 98% within 3h. The adsorption rate of Sr on 3A reached about 99% within 3h. (author). 40 refs., 27 figs., 4 tabs.

Analysis and optimization of triacylglycerol synthesis in novel oleaginous Rhodococcus and Streptomyces strains isolated from desert soil.

Science.gov (United States)

Röttig, Annika; Hauschild, Philippa; Madkour, Mohamed H; Al-Ansari, Ahmed M; Almakishah, Naief H; Steinbüchel, Alexander

2016-05-10

As oleaginous microorganisms represent an upcoming novel feedstock for the biotechnological production of lipids or lipid-derived biofuels, we searched for novel, lipid-producing strains in desert soil. This was encouraged by the hypothesis that neutral lipids represent an ideal storage compound, especially under arid conditions, as several animals are known to outlast long periods in absence of drinking water by metabolizing their body fat. Ten lipid-accumulating bacterial strains, affiliated to the genera Bacillus, Cupriavidus, Nocardia, Rhodococcus and Streptomyces, were isolated from arid desert soil due to their ability to synthesize poly(β-hydroxybutyrate), triacylglycerols or wax esters. Particularly two Streptomyces sp. strains and one Rhodococcus sp. strain accumulate significant amounts of TAG under storage conditions under optimized cultivation conditions. Rhodococcus sp. A27 and Streptomyces sp. G49 synthesized approx. 30% (w/w) fatty acids from fructose or cellobiose, respectively, while Streptomyces isolate G25 reached a cellular fatty acid content of nearly 50% (w/w) when cultivated with cellobiose. The stored triacylglycerols were composed of 30-40% branched fatty acids, such as anteiso-pentadecanoic or iso-hexadecanoic acid. To date, this represents by far the highest lipid content described for streptomycetes. A biotechnological production of such lipids using (hemi)cellulose-derived raw material could be used to obtain sustainable biodiesel with a high proportion of branched-chain fatty acids to improve its cold-flow properties and oxidative stability. Copyright © 2016 Elsevier B.V. All rights reserved.

Steady-state and pre-steady-state kinetic analysis of halopropane conversion by a Rhodococcus haloalkane dehalogenase

NARCIS (Netherlands)

Bosma, T; Pikkemaat, MG; Kingma, Jacob; Dijk, J; Janssen, DB

2003-01-01

Haloalkane dehalogenase from Rhodococcus rhodochrous NCIMB 13064 (DhaA) catalyzes the hydrolysis of carbon-halogen bonds in a wide range of haloalkanes. We examined the steady-state and pre-steady-state kinetics of halopropane conversion by DhaA to illuminate mechanistic details of the

An Adenoviral Vector Based Vaccine for Rhodococcus equi.

Directory of Open Access Journals (Sweden)

Carla Giles

Full Text Available Rhodococcus equi is a respiratory pathogen which primarily infects foals and is endemic on farms around the world with 50% mortality and 80% morbidity in affected foals. Unless detected early and treated appropriately the disease can be fatal. Currently, there is no vaccine available to prevent this disease. For decades researchers have endeavoured to develop an effective vaccine to no avail. In this study a novel human adenoviral vector vaccine for R. equi was developed and tested in the mouse model. This vaccine generated a strong antibody and cytokine response and clearance of R. equi was demonstrated following challenge. These results show that this vaccine could potentially be developed further for use as a vaccine to prevent R. equi disease in foals.

From oil spills to barley growth - oil-degrading soil bacteria and their promoting effects.

Science.gov (United States)

Mikolasch, Annett; Reinhard, Anne; Alimbetova, Anna; Omirbekova, Anel; Pasler, Lisa; Schumann, Peter; Kabisch, Johannes; Mukasheva, Togzhan; Schauer, Frieder

2016-11-01

Heavy contamination of soils by crude oil is omnipresent in areas of oil recovery and exploitation. Bioremediation by indigenous plants in cooperation with hydrocarbon degrading microorganisms is an economically and ecologically feasible means to reclaim contaminated soils. To study the effects of indigenous soil bacteria capable of utilizing oil hydrocarbons on biomass production of plants growing in oil-contaminated soils eight bacterial strains were isolated from contaminated soils in Kazakhstan and characterized for their abilities to degrade oil components. Four of them, identified as species of Gordonia and Rhodococcus turned out to be effective degraders. They produced a variety of organic acids from oil components, of which 59 were identified and 7 of them are hitherto unknown acidic oil metabolites. One of them, Rhodococcus erythropolis SBUG 2054, utilized more than 140 oil components. Inoculating barley seeds together with different combinations of these bacterial strains restored normal growth of the plants on contaminated soils, demonstrating the power of this approach for bioremediation. Furthermore, we suggest that the plant promoting effect of these bacteria is not only due to the elimination of toxic oil hydrocarbons but possibly also to the accumulation of a variety of organic acids which modulate the barley's rhizosphere environment. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Kinetics of hydrocarbon extraction from oil shale using biosurfactant producing bacteria

Energy Technology Data Exchange (ETDEWEB)

Haddadin, Malik S.Y.; Abou Arqoub, Ansam A.; Abu Reesh, Ibrahim [Faculty of Graduate Studies, Jordan University, Queen Rania Street, Amman, 11942 (Jordan); Haddadin, Jamal [Faculty of Agriculture, Mutah University, P.O. Box 59, Mutah 61710 (Jordan)

2009-04-15

This study was done to extract hydrocarbon compounds from El-Lajjun oil shale using biosurfactant produced from two strains Rhodococcus erythropolis and Rhodococcus ruber. The results have shown that, optimal biosurfactant production was found using naphthalene and diesel as a carbon source for R. erthropolis and R. ruber, respectively. Optimum nitrogen concentration was 9 g/l and 7 g/l for R. erthropolis and R. ruber, respectively. Optimum K{sub 2}HPO{sub 4} to KH{sub 2}PO{sub 4} ratio, temperature, pH, and agitation speeds were 2:1, 37 C, 7 and 200 rpm. Under optimal conditions R. erthropolis and R. ruber produced 5.67 and 6.9 g/l biosurfactant, respectively. Maximum recovery of oil achieved with hydrogen peroxide pre-treatment was 25% and 26% at biosurfactant concentration of 8 g/l and 4 g/l for R. erthropolis and R. ruber, respectively. The extent desorption of hydrocarbons from the pre-treated oil shale by biosurfactant were inversely related to the concentration of high molecular weight hydrocarbons, asphaltenes compounds. Pre-treatment of oil shale with hydrogen peroxide produced better improvement in aromatic compounds extraction in comparison with improvement which resulted from demineralization of the oil shale. (author)

CS Informativeness Governs CS-US Associability

Science.gov (United States)

Ward, Ryan D.; Gallistel, C. R.; Jensen, Greg; Richards, Vanessa L.; Fairhurst, Stephen; Balsam, Peter D

2012-01-01

In a conditioning protocol, the onset of the conditioned stimulus (CS) provides information about when to expect reinforcement (the US). There are two sources of information from the CS in a delay conditioning paradigm in which the CS-US interval is fixed. The first depends on the informativeness, the degree to which CS onset reduces the average expected time to onset of the next US. The second depends only on how precisely a subject can represent a fixed-duration interval (the temporal Weber fraction). In three experiments with mice, we tested the differential impact of these two sources of information on rate of acquisition of conditioned responding (CS-US associability). In Experiment 1, we show that associability (the inverse of trials to acquisition) increases in proportion to informativeness. In Experiment 2, we show that fixing the duration of the US-US interval or the CS-US interval or both has no effect on associability. In Experiment 3, we equated the increase in information produced by varying the C̅/T̅ ratio with the increase produced by fixing the duration of the CS-US interval. Associability increased with increased informativeness, but, as in Experiment 2, fixing the CS-US duration had no effect on associability. These results are consistent with the view that CS-US associability depends on the increased rate of reward signaled by CS onset. The results also provide further evidence that conditioned responding is temporally controlled when it emerges. PMID:22468633

Pulmonary Rhodococcus equi infection: report of the first two Brazilian cases

OpenAIRE

SEVERO, LUIZ CARLOS; RITTER, PATRICIA; PETRILLO, VICTOR FLÁVIO; DIAS, CÍCERO ARMÍDIO GOMES; PORTO, NELSON DA SILVA

2001-01-01

O Rhodococcus equi, principal agente da rodococose, é um cocobacilo pleomórfico, gram-positivo e aeróbio, que infecta humanos por via inalatória ou transcutânea e se manifesta clinicamente como abscesso pulmonar. Relatam-se os dois primeiros casos brasileiros da doença. Ambos os pacientes eram imunocomprometidos e apresentavam quadro infeccioso pulmonar. O primeiro tinha AIDS e apresentava pneumonia cavitada em lobo superior esquerdo, que teve evolução fatal. O segundo tinha doença de Goodpas...

Genetically engineered micro-organisms: Aromatic hydrocarbon biodegradation genes from Rhodococcus

International Nuclear Information System (INIS)

Kendall, K.

1993-01-01

DNA known to encode toluene biodegradation genes in Pseudomonas putida was used in Southern Blots to identify homologous DNA in the unrelated toluene degrading Actinomycete, Rhodococcus sp. ATCC 19070. Two strongly hybridizing EcoRI fragments of 2.3 kb and 2.7 kb respectively were cloned into E. coli. Sequence analysis of a 400 bp section of the 2.3 kb fragment demonstrated that it encodes proteins with similar amino acid sequences to the xylX and xylY genes of P. putida. These proteins are components of toluate oxygenase, the enzyme catalyzing the first step in the metabolism of benzoic acid

Molecular characterization of three 3-ketosteroid-Delta(1)-dehydrogenase isoenzynnes of Rhodococcus ruber strain Chol-4

NARCIS (Netherlands)

Fernandez de las Heras, Laura; van der Geize, Robert; Drzyzga, Oliver; Perera, Julian; Navarro Llorens, Juana Maria

2012-01-01

Rhodococcus ruber strain Chol-4 isolated from a sewage sludge sample is able to grow on minimal medium supplemented with steroids, showing a broad catabolic capacity. This paper reports the characterization of three different 3-ketosteroid-Delta(1)-dehydrogenases (KstDs) in the genome of R. ruber

Molecular structures and thermodynamic properties of 12 gaseous cesium-containing species of nuclear safety interest: Cs 2, CsH, CsO, Cs 2O, CsX, and Cs 2X 2 (X = OH, Cl, Br, and I)

Science.gov (United States)

Badawi, Michael; Xerri, Bertrand; Canneaux, Sébastien; Cantrel, Laurent; Louis, Florent

2012-01-01

Ab initio electronic structure calculations at the coupled cluster level with a correction for the triples extrapolated to the complete basis set limit have been made for the estimation of the thermochemical properties of Cs 2, CsH, CsO, Cs 2O, CsX, and Cs 2X 2 (X = OH, Cl, Br, and I). The standard enthalpies of formation and standard molar entropies at 298 K, and the temperature dependence of the heat capacities at constant pressure were evaluated. The calculated thermochemical properties are in good agreement with their literature counterparts. For Cs 2, CsH, CsOH, Cs 2(OH) 2, CsCl, Cs 2Cl 2, CsBr, CsI, and Cs 2I 2, the calculated ΔfH298K∘ values are within chemical accuracy of the most recent experimental values. Based on the excellent agreement observed between our calculated ΔfH298K∘ values and their literature counterparts, the standard enthalpies of formation at 298 K are estimated to be the following: ΔfH298K∘ (CsO) = 17.0 kJ mol -1 and ΔfH298K∘ (Cs 2Br 2) = -575.4 kJ mol -1.

Infection by rhodococcus fascians maintains cotyledons as a sink tissue for the pathogen

Czech Academy of Sciences Publication Activity Database

Dhandapani, P.; Song, J.; Novák, Ondřej; Jameson, P. E.

2017-01-01

Roč. 119, č. 5 (2017), s. 841-852 ISSN 0305-7364 R&D Projects: GA MŠk(CZ) LO1204; GA MŠk LK21306 Institutional support: RVO:61389030 Keywords : Amino acid transporter * Apical dominance * Cell wall invertase * Cytokinin * Cytokinin oxidase/dehydro-genase * Pea * Pisum sativum L. * Rhodococcus fascians * Seed * Sink and source * Sucrose transporter * sweet Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 4.041, year: 2016

Evidence for an Inducible Nucleotide-Dependent Acetone Carboxylase in Rhodococcus rhodochrous B276

OpenAIRE

Clark, Daniel D.; Ensign, Scott A.

1999-01-01

The metabolism of acetone was investigated in the actinomycete Rhodococcus rhodochrous (formerly Nocardia corallina) B276. Suspensions of acetone- and isopropanol-grown R. rhodochrous readily metabolized acetone. In contrast, R. rhodochrous cells cultured with glucose as the carbon source lacked the ability to metabolize acetone at the onset of the assay but gained the ability to do so in a time-dependent fashion. Chloramphenicol and rifampin prevented the time-dependent increase in this acti...

[Effects of nitriles and amides on the growth and the nitrile hydratase activity of the Rhodococcus sp. strain gt1].

Science.gov (United States)

Maksimov, A Iu; Kuznetsova, M V; Ovechkina, G V; Kozlov, S V; Maksimova, Iu G; Demakov, V A

2003-01-01

Effects of some nitriles and amides, as well as glucose and ammonium, on the growth and the nitrile hydratase (EC 4.2.1.84) activity of the Rhodococcus sp. strain gt1 isolated from soil were studied. The activity of nitrile hydratase mainly depended on carbon and nitrogen supply to cells. The activity of nitrile hydratase was high in the presence of glucose and ammonium at medium concentrations and decreased at concentrations of glucose more than 0.3%. Saturated unsubstituted aliphatic nitriles and amides were found to be a good source of nitrogen and carbon. However, the presence of nitriles and amides in the medium was not absolutely necessary for the expression of the activity of nitrile hydratase isolated from the Rhodococcus sp. strain gt1.

Identification and analysis of novel virulence-defective Rhodococcus fascians mutants

OpenAIRE

Cabecinhas, Adriana Sofia Silva

2014-01-01

Rhodococcus fascians é uma actinomiceta fitopatogénica que induz uma doença, conhecida como irritação frondosa, caracterizada pela indução de múltiplos rebentos, numa vasta gama de plantas herbáceas dicotiledóneas. O principal factor de patogenicidade da bactéria é a produção de uma mistura de 6 citoquininas codificadas pelos genes do operão fas que está localizado num plasmídeo linear associado à virulência, pFiD188. Este trabalho teve como objectivo a análise de dois novos loci deste plasmí...

Biocatalytic properties and structural analysis of eugenol oxidase from Rhodococcus jostii RHA1 : a versatile oxidative biocatalyst

NARCIS (Netherlands)

Nguyen, Quoc-Thai; De Gonzalo, Gonzalo; Binda, Claudia; Rioz, Ana; Mattevi, Andrea; Fraaije, Marco

2016-01-01

Eugenol oxidase (EUGO) from Rhodococcus jostii RHA1 was previously shown to convert only a limited set of phenolic compounds. In this study, we have explored the biocatalytic potential of this flavoprotein oxidase resulting in a broadened substrate scope and a deeper insight into its structural

Growth kinetics and biodeterioration of polypropylene microplastics by Bacillus sp. and Rhodococcus sp. isolated from mangrove sediment.

Science.gov (United States)

Auta, H S; Emenike, C U; Jayanthi, B; Fauziah, S H

2018-02-01

Interest in the biodegradation of microplastics is due to their ubiquitous distribution, availability, high persistence in the environment and deleterious impact on marine biota. The present study evaluates the growth response and mechanism of polypropylene (PP) degradation by Bacillus sp. strain 27 and Rhodococcus sp. strain 36 isolated from mangrove sediments upon exposure to PP microplastics. Both bacteria strains were able to utilise PP microplastic for growth as confirmed by the reduction of the polymer mass. The weight loss was 6.4% by Rhodococcus sp. strain 36 and 4.0% by Bacillus sp. strain 27 after 40days of incubation. PP biodegradation was further confirmed using Fourier-transform infrared spectroscopy and scanning electron microscopy analyses, which revealed structural and morphological changes in the PP microplastics with microbial treatment. These analyses showed that the isolates can colonise, modify and utilise PP microplastics as carbon source. Copyright © 2017 Elsevier Ltd. All rights reserved.

Molecular CsF 5 and CsF 2 +

KAUST Repository

Rogachev, Andrey Yu.; Miao, Mao-sheng; Merino, Gabriel; Hoffmann, Roald

2015-01-01

D5h star-like CsF5, formally isoelectronic with known XeF5− ion, is computed to be a local minimum on the potential energy surface of CsF5, surrounded by reasonably large activation energies for its exothermic decomposition to CsF+2 F2, or to CsF3 (three isomeric forms)+F2, or for rearrangement to a significantly more stable isomer, a classical Cs+ complex of F5−. Similarly the CsF2+ ion is computed to be metastable in two isomeric forms. In the more symmetrical structures of these molecules there is definite involvement in bonding of the formally core 5p levels of Cs.

Molecular CsF 5 and CsF 2 +

KAUST Repository

Rogachev, Andrey Yu.

2015-06-03

D5h star-like CsF5, formally isoelectronic with known XeF5− ion, is computed to be a local minimum on the potential energy surface of CsF5, surrounded by reasonably large activation energies for its exothermic decomposition to CsF+2 F2, or to CsF3 (three isomeric forms)+F2, or for rearrangement to a significantly more stable isomer, a classical Cs+ complex of F5−. Similarly the CsF2+ ion is computed to be metastable in two isomeric forms. In the more symmetrical structures of these molecules there is definite involvement in bonding of the formally core 5p levels of Cs.

Identification of microbial carotenoids and isoprenoid quinones from Rhodococcus sp. B7740 and its stability in the presence of iron in model gastric conditions.

Science.gov (United States)

Chen, Yashu; Xie, Bijun; Yang, Jifang; Chen, Jigang; Sun, Zhida

2018-02-01

Rhodococcus sp. B7740 is a newfound bacterium which was isolated from 25m deep seawater in the arctic. In this paper, Rhodococcus sp. B7740 was firstly discovered to produce abundant natural isoprenoids, including ubiquinone-4(UQ-4), 13 kinds of menaquinones, three rare aromatic carotenoids and more than one common carotenoid. These compounds were identified by UV-Visible, HPLC-APCI-MS/MS and HRMS spectra. Results demonstrated that Rhodococcus sp. B7740 might be a worthy source of natural isoprenoids especially for scarce aromatic carotenoids. Among them, isorenieratene with 528.3762Da (calculated for 528.3756Da, error: 1.1ppm), a carotenoid with aromatic ring, was purified by HSCCC. The stability of isorenieratene under the mimical gastric conditions was measured compared with common dietary carotenoids, β-carotene and lutein. Unlike β-carotene and lutein, isorenieratene exhibited rather stable in the presence of free iron or heme iron. Its high retention rate in gastrointestinal tract after ingestion indicates the benefits for health. Copyright © 2017. Published by Elsevier Ltd.

El género Rhodococcus. Una revisión didáctica

OpenAIRE

Sánchez, N; Sandoval, AH; Díaz-Corrales, F; Serrano, JA

2004-01-01

Los autores presentan una extensa revisión sobre el género Rhodococcus, grupo de microorganismos pertenecientes a la familia de los Actinomicetales. Se revisan aspectos relativos a la microbiología, taxonomía, citoquímica, patología, clínica y terapéutica de las afecciones que, como agentes patógenos, producen estos microorganismos, en especial en su papel de agentes productores de infecciones nosocomiales y oportunistas. Así mismo se revisan aspectos relativos a la importancia de estos micro...

Application of two bacterial strains for wastewater bioremediation and assessment of phenolics biodegradation.

Science.gov (United States)

Paisio, Cintia E; Quevedo, María R; Talano, Melina A; González, Paola S; Agostini, Elizabeth

2014-08-01

The use of native bacteria is a useful strategy to decontaminate industrial effluents. In this work, two bacterial strains isolated from polluted environments constitutes a promising alternative since they were able to remove several phenolic compounds not only from synthetic solutions but also from effluents derived from a chemical industry and a tannery which are complex matrices. Acinetobacter sp. RTE 1.4 showed ability to completely remove 2-methoxyphenol (1000 mg/L) while Rhodococcus sp. CS 1 not only degrade the same concentration of this compound but also removed 4- chlorophenol, 2,4-dichlorophenol and pentachlorophenol with high efficiency. Moreover, both bacteria degraded phenols naturally present or even exogenously added at high concentrations in effluents from the chemical industry and a tannery in short time (up to 5 d). In addition, a significant reduction of biological oxygen demand and chemical oxygen demand values was achieved after 7 d of treatment for both effluents using Acinetobacter sp. RTE 1.4 and Rhodococcus sp. CS1, respectively. These results showed that Acinetobacter sp. RTE1.4 and Rhodococcus sp. CS 1 might be considered as useful biotechnological tools for an efficient treatment of different effluents, since they showed wide versatility to detoxify these complex matrices, even supplemented with high phenol concentrations.

Aerobic degradation of buprofezin via novel degradation intermediates by Rhodococcus sp. strain RX-3

OpenAIRE

Ruixue Li; Chun Dai; Guangli Wang; Shaoxian Wu; Yubao Gong; Yuanyuan Jiang; Zhijia Wang; Naiyue Sun

2016-01-01

Buprofezin is a commonly used chemical with satisfactory efficacy against sucking insect pests, but its disposal causes serious environmental problems. In this study, a bacterial strain RX-3 isolated by continuous enrichment from buprofezin-treated soil was tested for biodegradation of buprofezin. The bacteria were most similar to Rhodococcus sp. based on their morphological, physiological and biochemical characteristics, as well as phylogenetic placement inferred from 16S rRNA gene sequence....

Wild mushroom contamination by 137Cs in Central Slovakia region in 2011

International Nuclear Information System (INIS)

Durecova, Alzbeta; Durec, F.; Auxtova, L.; Cechova, A.

2012-01-01

A total of 98 wild mushrooms (24 species collected at 26 sites) were analyzed for 137 Cs in 2011. The radionuclide was determined separately in the caps and the stipes of the majority of the mushrooms species. The highest activities were found in the genera Boletus, Leccinum, Lactarius and Russula whereas the lowest activities were found in Amanita. In the vast majority of mushrooms, the cap-to-stipe 137 Cs activity ratio was larger than 1. The cap-to-stipe 137 Cs activity ratio did not correlate with the cap-to-stipe 40 K activity ratio in Russula or Amanita. The cap of a Boletus pulverulentus specimen collected at Skalka pri Kremnici in August had a 137 Cs activity 190 Bq/kg fresh sample. For an individual who ate 10 kg of fresh caps of this mushroom during a year, their committed effective dose estimate is 0.025 mSv/year (adults) or 0.019 mSv/year (children aged 10). (orig.)

Crystal structure and thermal behaviour of boro-pollucite CsBSi2O6

International Nuclear Information System (INIS)

Bubnova, R.S.; Stepanov, N.K.; Filatov, S.K.; Levin, A.A.; Paufler, P.; Meyer, D.C.

2004-01-01

The crystal structure of Cs 0.82 B 1.09 Si 1.98 O 6 boro-pollucite at room temperature was determined by direct methods and refined in the l a 3-bar d space group using an anisotropic approximation of atomic thermal displacements (a = 13.009 (1) angstrom, Z = 16, R w = 0.027, R F = 0.037 for 141 independent observed (IFI ≥4σ F ) reflections). The occupancy factors have been refined for Cs and tetrahedral positions assuming the oxygen sites being fully occupied. The compound is isostructural to leucite pollucite high-temperature modification. Thermal behaviour of CsBSi 2 O 6 was investigated by DTA and TG, annealing at different temperatures with following wet chemical analysis and high-temperature X-ray powder diffraction methods. The CsBSi 2 O 6 cubic phase loses mass before melting and decomposes to form a new crystalline phase with close to CsBSi 3 O 8 stoichiometry in the temperature range of 1303 353 K. Thermal expansion of two boro-pollucite samples, which differed in the number of Cs + and/or B 3+ ions of a nominal composition CsBSi 2 O 6 was investigated in air as well as in vacuum. Temperature ranges of negative thermal expansion were found. (authors)

Haloalkane-utilizing Rhodococcus strains isolated from geographically distinct locations possess a highly conserved gene cluster encoding haloalkane catabolism

NARCIS (Netherlands)

Poelarends, GJ; Bosma, T; Kulakov, LA; Larkin, MJ; Marchesi, [No Value; Weightman, AJ; Janssen, DB; Kulakov, Leonid A.; Larkin, Michael J.; Marchesi, Julian R.; Weightman, Andrew J.

The sequences of the 16S rRNA and haloalkane dehalogenase (dhaA) genes of five gram-positive haloalkane-utilizing bacteria isolated from contaminated sites in Europe, Japan, and the United States and of the archetypal haloalkane-degrading bacterium Rhodococcus sp. strain NCIMB13064 were compared.

Failure of pulmonary clearance of Rhodococcus equi infection in CD4+ T-lymphocyte-deficient transgenic mice.

OpenAIRE

Kanaly, S T; Hines, S A; Palmer, G H

1993-01-01

Pulmonary clearance of Rhodococcus equi requires functional T lymphocytes. In this study, CD8+ T-lymphocyte-deficient transgenic mice cleared virulent R. equi from the lungs while infection in CD4+ T-lymphocyte-deficient transgenic mice persisted. Although both CD4+ and CD8+ T cells function early in pulmonary defense against R. equi, clearance is dependent on CD4+ T lymphocytes.

Genetic diversity of culturable bacteria in oil-contaminated rhizosphere of Galega orientalis

International Nuclear Information System (INIS)

Jussila, Minna M.; Jurgens, German; Lindstroem, Kristina; Suominen, Leena

2006-01-01

A collection of 50 indigenous meta-toluate tolerating bacteria isolated from oil-contaminated rhizosphere of Galega orientalis on selective medium was characterized and identified by classical and molecular methods. 16S rDNA partial sequencing showed the presence of five major lineages of the Bacteria domain. Gram-positive Rhodococcus, Bacillus and Arthrobacter and gram-negative Pseudomonas were the most abundant genera. Only one-fifth of the strains that tolerated m-toluate also degraded m-toluate. The inoculum Pseudomonas putida PaW85 was not found in the rhizosphere samples. The ability to degrade m-toluate by the TOL plasmid was detected only in species of the genus Pseudomonas. However, a few Rhodococcus erythropolis strains were found which were able to degrade m-toluate. A new finding was that Pseudomonas migulae strains and a few P. oryzihabitans strains were able to grow on m-toluate and most likely contained the TOL plasmid. Because strain specific differences in degradation abilities were found for P. oryzihabitans, separation at the strain level was important. For strain specific separation (GTG) 5 fingerprinting was the best method. A combination of the single locus ribotyping and the whole genomic fingerprinting techniques with the selective partial sequencing formed a practical molecular toolbox for studying genetic diversity of culturable bacteria in oil-contaminated rhizosphere. - Bacterial diversity during rhizoremediation in oil-contaminated soil is characterized by a combination of molecular methods

Plasmid Vectors for Testing In Vivo Promoter Activities in Corynebacterium glutamicum and Rhodococcus erythropolis

Czech Academy of Sciences Publication Activity Database

Knoppová, Monika; Phensaijai, M.; Veselý, Martin; Zemanová, Martina; Nešvera, Jan; Pátek, Miroslav

2007-01-01

Roč. 55, - (2007), s. 234-239 ISSN 0343-8651 R&D Projects: GA ČR GA526/04/0542; GA ČR GA204/06/0330 Institutional research plan: CEZ:AV0Z50200510 Keywords : corynebacterium * rhodoccoccus * promoter-probe vectors Subject RIV: EE - Microbiology , Virology Impact factor: 1.167, year: 2007

Improved Method for the Isolation of Biosurfactant Glycolipids from Rhodococcus sp. Strain H13A

OpenAIRE

Bryant, Frank O.

1990-01-01

An improved method for the isolation of the biosurfactant glycolipids from Rhodococcus sp. strain H13A by using XM 50 diafiltration and isopropanol precipitation was devised. This procedure was advantageous since it removes protein coisolated when the glycolipids are obtained by organic extraction and silicic acid chromatography. The protein apparently does not contribute any biosurfactant characteristics to the glycolipids. The deacylated glycolipid backbone included only a disaccharide.

Benzoate Catabolite Repression of the Phthalate Degradation Pathway in Rhodococcus sp. Strain DK17▿

OpenAIRE

Choi, Ki Young; Zylstra, Gerben J.; Kim, Eungbin

2006-01-01

Rhodococcus sp. strain DK17 exhibits a catabolite repression-like response when provided simultaneously with benzoate and phthalate as carbon and energy sources. Benzoate in the medium is depleted to detection limits before the utilization of phthalate begins. The transcription of the genes encoding benzoate and phthalate dioxygenase paralleled the substrate utilization profile. Two mutant strains with defective benzoate dioxygenases were unable to utilize phthalate in the presence of benzoat...

Genome-based exploration of the specialized metabolic capacities of the genus Rhodococcus.

Science.gov (United States)

Ceniceros, Ana; Dijkhuizen, Lubbert; Petrusma, Mirjan; Medema, Marnix H

2017-08-09

Bacteria of the genus Rhodococcus are well known for their ability to degrade a large range of organic compounds. Some rhodococci are free-living, saprophytic bacteria; others are animal and plant pathogens. Recently, several studies have shown that their genomes encode putative pathways for the synthesis of a large number of specialized metabolites that are likely to be involved in microbe-microbe and host-microbe interactions. To systematically explore the specialized metabolic potential of this genus, we here performed a comprehensive analysis of the biosynthetic coding capacity across publicly available rhododoccal genomes, and compared these with those of several Mycobacterium strains as well as that of their mutual close relative Amycolicicoccus subflavus. Comparative genomic analysis shows that most predicted biosynthetic gene cluster families in these strains are clade-specific and lack any homology with gene clusters encoding the production of known natural products. Interestingly, many of these clusters appear to encode the biosynthesis of lipopeptides, which may play key roles in the diverse environments were rhodococci thrive, by acting as biosurfactants, pathogenicity factors or antimicrobials. We also identified several gene cluster families that are universally shared among all three genera, which therefore may have a more 'primary' role in their physiology. Inactivation of these clusters by mutagenesis might help to generate weaker strains that can be used as live vaccines. The genus Rhodococcus thus provides an interesting target for natural product discovery, in view of its large and mostly uncharacterized biosynthetic repertoire, its relatively fast growth and the availability of effective genetic tools for its genomic modification.

Pneumonia due to Rhodococcus equi in a non-Hodgkin's lymphoma patient: case report

Directory of Open Access Journals (Sweden)

Iuri de França Bonilha

Full Text Available The authors reported a lung infection by Rhodococcus equi in a 25 years-old male patient admitted to hospital with cough, dyspnea, fever, and previous diagnosis of pleural effusion. R. equi was isolated from pleural fluid and the patient acquired nosocomial infection by Acinetobacter baumannii, isolated from chest drain. The patient was treated with antibiotics. During hospitalization, he was diagnosed with non-Hodgkin lymphoma of precursor T-cell lymphoblastic lymphoma subtype in biopsy of pleura. After undergoing surgery for pulmonary decortication for drain empyema, the patient died due to septicemia.

Sorption of Cs onto γ-Al2O3 using batch technique

International Nuclear Information System (INIS)

Wang Xiangke

2004-01-01

The sorption of Cs onto γ-Al 2 O 3 is studied by using batch technique, ultra-filtration method and UV vis spectrophotometer at room temperature, pH 4.0, 6.0 and 8.0, the ionic strength of NaClO 4 is from 0.001 mol/L to 0.1 mol/L. The concentration of humic acid in the solution is determined at wavelength of 254 nm. The sorption of humic acid on the γ-Al 2 O 3 is strong (≅98% HA is sorbed on the surface of alumina at pH zpc =9.2)) and strongly dependent on pH values. At pH>9.2, the sorption of HA is decreased markedly with the increasing of pH. Humic acid has a little negative effect on the sorption of Cs onto alumina, this may be attributed to the formation of HA-Cs complexation in the solution. The sorption of Cs onto γ-Al 2 O 3 is weakly dependent on the pH and independent on the ionic strength. Freundlich isotherm can fit the sorption isotherms very well. The sorption of Cs onto γ-Al 2 O 3 may be contributed to cation exchange and surface complexation mechanisms. (authors)

Enzymatic cyanide degradation by cell-free extract of Rhodococcus UKMP-5M.

Science.gov (United States)

Nallapan Maniyam, Maegala; Sjahrir, Fridelina; Latif Ibrahim, Abdul; Cass, Anthony E G

2015-01-01

The cell-free extract of locally isolated Rhodococcus UKMP-5M strain was used as an alternative to develop greener and cost effective cyanide removal technology. The present study aims to assess the viability of the cell-free extract to detoxify high concentrations of cyanide which is measured through the monitoring of protein concentration and specific cyanide-degrading activity. When cyanide-grown cells were subjected to grinding in liquid nitrogen which is relatively an inexpressive and fast cell disruption method, highest cyanide-degrading activity of 0.63 mM min(-1) mg(-1) protein was obtained in comparison to enzymatic lysis and agitation with fine glass beads. The cell-free extracts managed to degrade 80% of 20 mM KCN within 80 min and the rate of cyanide consumption increased linearly as the concentration of protein was raised. In both cases, the addition of co-factor was not required which proved to be advantageous economically. The successful formation of ammonia and formate as endproducts indicated that the degradation of cyanide by Rhodococcus UKMP-5M proceeded via the activity of cyanidase and the resulting non-toxic products are safe for disposal into the environment. Further verification with SDS-PAGE revealed that the molecular weight of the active enzyme was estimated to be 38 kDa, which is consistent with previously reported cyanidases. Thus, the utilization of cell-free extracts as an alternative to live microbial in cyanide degradation offers numerous advantageous such as the potential to tolerate and degrade higher concentration of cyanide and total reduction in the overall cost of operation since the requirement for nutrient support is irrelevant.

Variación de la composición de ácidos grasos de membrana celular de Rhodococcus rodochrous GNP-OHP-38r en respuesta a la temperatura y salinidad Variation in the composition of Rhodococcus rodochrous GNP-OHP-38r cell membrane fatty acids in response to temperature and salinity

Directory of Open Access Journals (Sweden)

G.N. Pucci

2004-06-01

Full Text Available Los integrantes del género Rhodococcus son habitantes frecuentes y abundantes de áreas contaminadas con hidrocarburos y resisten la creciente salinidad que se presenta en la Patagonia central. Este género tiene buena capacidad de eliminar contaminantes hidrocarburos que constituyen el mayor contaminante de la región. En el presente trabajo se estudió la respuesta en la composición de sus ácidos grasos de una cepa aislada de un sistema de landfarming, ante la acción combinada de diferentes temperaturas y concentraciones salinas. La estrategia de la cepa Rhodococcus rodochrous GNP-OHP-38r frente al incremento de temperatura, es el aumento del porcentaje de los ácidos grasos saturados totales (n:0; ácidos grasos ramificados en el carbono terminal con grupos oxidrilo en posición 2 (n:0 iso 2 OH y saturados con grupo metilo en carbono 10 (n:0 10 metil, a expensas de la disminución del porcentaje de los n:1 cis.The members of the genus Rhodococcus are frequent and abundant inhabitants of polluted areas with hydrocarbons and they resist the salinity present in the central Patagonia. This genus has good capacity to eliminate pollution produced by hydrocarbons that constitutes the biggest pollutant agent in the region. The present work studies the answer in the composition of its fatty acids under the combined action of the temperature and saline concentration of an isolated stump of a landfarming system. The strategy of Rhodococcus rodochrous strain GNP-OHP-38r in front of the thermal-osmotic stress is the increase of the percentage of the total saturated fatty acids (n:0; fatty acids branched in the terminal carbon with hidroxyl group in position 2 (n:0 iso 2 OH and saturated with group methyl in carbon 10 (n:0 10 metil when the temperature is increased. These acids increase while the percentage of n:1 cis decrease.

Rhodococcus rhodochrous DSM 43269 3-Ketosteroid 9 alpha-Hydroxylase, a Two-Component Iron-Sulfur-Containing Monooxygenase with Subtle Steroid Substrate Specificity

NARCIS (Netherlands)

Petrusma, M.; Dijkhuizen, L.; van der Geize, R.

2009-01-01

This paper reports the biochemical characterization of a purified and reconstituted two-component 3-ketosteroid 9 alpha-hydroxylase (KSH). KSH of Rhodococcus rhodochrous DSM 43269, consisting of a ferredoxin reductase (KshB) and a terminal oxygenase (KshA), was heterologously expressed in

Members of the genera Paenibacillus and Rhodococcus harbor genes homologous to enterococcal glycopeptide resistance genes vanA and vanB

DEFF Research Database (Denmark)

Guardabassi, L.; Christensen, H.; Hasman, Henrik

2004-01-01

Genes homologous to enterococcal glycopeptide resistance genes vanA and vanB were found in glycopeptide-resistant Paenibacillus and Rhodococcus strains from soil. The putative D-Ala:D-Lac ligase genes in Paenibacillus thiaminolyticus PT-2B1 and Paenibacillus apiarius PA-B2B were closely related...

Cloning, overexpression, purification, crystallization and preliminary X-ray analysis of 3-ketosteroid Delta(4)-(5 alpha)-dehydrogenase from Rhodococcus jostii RHA1

NARCIS (Netherlands)

van Oosterwijk, Niels; Knol, Jan; Dijkhuizen, Lubbert; van der Geize, Robert; Dijkstra, Bauke

2011-01-01

3-Ketosteroid dehydrogenases are flavoproteins which play key roles in steroid ring degradation. The enzymes are abundantly present in actinobacteria, including the catabolic powerhouse Rhodococcus jostii and the pathogenic species R. equi and Mycobacterium tuberculosis. The gene for 3-ketosteroid

Antibodies derived from an enterotoxigenic Escherichia coli (ETEC) adhesin tip MEFA (multiepitope fusion antigen) against adherence of nine ETEC adhesins: CFA/I, CS1, CS2, CS3, CS4, CS5, CS6, CS21 and EtpA.

Science.gov (United States)

Nandre, Rahul M; Ruan, Xiaosai; Duan, Qiangde; Sack, David A; Zhang, Weiping

2016-06-30

Diarrhea continues to be a leading cause of death in children younger than 5 years in developing countries. Enterotoxigenic Escherichia coli (ETEC) is a leading bacterial cause of children's diarrhea and travelers' diarrhea. ETEC bacteria initiate diarrheal disease by attaching to host receptors at epithelial cells and colonizing in small intestine. Therefore, preventing ETEC attachment has been considered the first line of defense against ETEC diarrhea. However, developing vaccines effectively against ETEC bacterial attachment encounters challenge because ETEC strains produce over 23 immunologically heterogeneous adhesins. In this study, we applied MEFA (multiepitope fusion antigen) approach to integrate epitopes from adhesin tips or adhesive subunits of CFA/I, CS1, CS2, CS3, CS4, CS5, CS6, CS21 and EtpA adhesins and to construct an adhesin tip MEFA peptide. We then examined immunogenicity of this tip MEFA in mouse immunization, and assessed potential application of this tip MEFA for ETEC vaccine development. Data showed that mice intraperitoneally immunized with this adhesin tip MEFA developed IgG antibody responses to all nine ETEC adhesins. Moreover, ETEC and E. coli bacteria expressing these nine adhesins, after incubation with serum of the immunized mice, exhibited significant reduction in attachment to Caco-2 cells. These results indicated that anti-adhesin antibodies induced by this adhesin tip MEFA blocked adherence of the most important ETEC adhesins, suggesting this multivalent tip MEFA may be useful for developing a broadly protective anti-adhesin vaccine against ETEC diarrhea. Copyright © 2016 Elsevier Ltd. All rights reserved.

Molecular CsF{sub 5} and CsF{sub 2}{sup +}

Energy Technology Data Exchange (ETDEWEB)

Rogachev, Andrey Yu. [Illinois Institute of Technology, IL (United States). Dept. of Biological and Chemical Sciences; Miao, Mao-sheng [California State Univ., Northridge, CA (United States). Dept. of Chemistry and Biochemistry; Beijing Computational Science Research Center (China); Merino, Gabriel [Centro de Investigacion y de Estudios Avanzados, Unidad Merida (Mexico). Dept. de Fisica Aplicada; Hoffmann, Roald [Cornell Univ., Ithaca, NY (United States). Dept. of Chemistry and Chemical Biology

2015-07-06

D{sub 5h} star-like CsF{sub 5}, formally isoelectronic with known XeF{sub 5}{sup -} ion, is computed to be a local minimum on the potential energy surface of CsF{sub 5}, surrounded by reasonably large activation energies for its exothermic decomposition to CsF + 2F{sub 2}, or to CsF{sub 3} (three isomeric forms) + F{sub 2}, or for rearrangement to a significantly more stable isomer, a classical Cs{sup +} complex of F{sub 5}{sup -}. Similarly the CsF{sub 2}{sup +} ion is computed to be metastable in two isomeric forms. In the more symmetrical structures of these molecules there is definite involvement in bonding of the formally core 5p levels of Cs.

Migration and chemical extractability of 137Cs and 90Sr in Swedish long-term experimental pastures

International Nuclear Information System (INIS)

Forsberg, S.; Strandmark, M.

1999-01-01

Vertical migration and chemical extractability were studied on two experimental pastures, a sandy soil and a clay soil, contaminated with 137 Cs and 90 Sr in 1961. Migration was studied by measuring the total nuclide content in soil samples to 55 cm depth, chemical extractability by sequential extraction. Both 137 Cs and 90 Sr were found at all depths in both soils, and 90 Sr had moved deeper than 137 Cs. 137 Cs was mainly found in the upper 10 cm, and no difference was seen between clay and sandy soil, due to retention in the root mat of the sandy soil. 90 Sr had moved deeper in sandy than in clay soil, the reason being the higher exchange capacity of the clay soil. Sequential extractions showed that 90 Sr was much more extractable than 137 Cs. 96-98% of 137 Cs was found in the HNO 3 and residual fractions. 137 Cs was more extractable in the sandy soil than in clay, and in the sandy soil the extractability of 137 Cs increased slightly with depth. Regarding 90 Sr, 63-75% was found in the easily exchangeable fractions, the higher figure was in clay soil. A large proportion, 18-30%, was extracted in the reducible fraction, showing that availability of 90 Sr might increase under reducing conditions. (au)

Toxicity evaluation of 2-hydroxybiphenyl and other compounds involved in studies of fossil fuels biodesulphurisation.

Science.gov (United States)

Alves, L; Paixão, S M

2011-10-01

The acute toxicity of some compounds used in fossil fuels biodesulphurisation studies, on the respiration activity, was evaluated by Gordonia alkanivorans and Rhodococcus erythropolis. Moreover, the effect of 2-hydroxybiphenyl on cell growth of both strains was also determined, using batch (chronic bioassays) and continuous cultures. The IC₅₀ values obtained showed the toxicity of all the compounds tested to both strains, specially the high toxicity of 2-HBP. These results were confirmed by the chronic toxicity data. The toxicity data sets highlight for a higher sensitivity to the toxicant by the strain presenting a lower growth rate, due to a lower cells number in contact with the toxicant. Thus, microorganisms exhibiting faster generation times could be more resistant to 2-HBP accumulation during a BDS process. The physiological response of both strains to 2-HBP pulse in a steady-state continuous culture shows their potential to be used in a future fossil fuel BDS process. Copyright © 2011 Elsevier Ltd. All rights reserved.

Transformation of saturated nitrogen-containing heterocyclic compounds by microorganisms.

Science.gov (United States)

Parshikov, Igor A; Silva, Eliane O; Furtado, Niege A J C

2014-02-01

The saturated nitrogen-containing heterocyclic compounds include many drugs and compounds that may be used as synthons for the synthesis of other pharmacologically active substances. The need for new derivatives of saturated nitrogen-containing heterocycles for organic synthesis, biotechnology and the pharmaceutical industry, including optically active derivatives, has increased interest in microbial synthesis. This review provides an overview of microbial technologies that can be valuable to produce new derivatives of saturated nitrogen-containing heterocycles, including hydroxylated derivatives. The chemo-, regio- and enantioselectivity of microbial processes can be indispensable for the synthesis of new compounds. Microbial processes carried out with fungi, including Beauveria bassiana, Cunninghamella verticillata, Penicillium simplicissimum, Aspergillus niger and Saccharomyces cerevisiae, and bacteria, including Pseudomonas sp., Sphingomonas sp. and Rhodococcus erythropolis, biotransform many substrates efficiently. Among the biological activities of saturated nitrogen-containing heterocyclic compounds are antimicrobial, antitumor, antihypertensive and anti-HIV activities; some derivatives are effective for the treatment and prevention of malaria and trypanosomiasis, and others are potent glycosidase inhibitors.

Bio-desulfurization technology in Japan; Wagakuni ni okeru baio datsuryu gijutsu

Energy Technology Data Exchange (ETDEWEB)

Maruhashi, K. [Petroleum Energy Center, Tokyo (Japan)

2000-05-01

A bio-reaction of microbes (catalytic reaction by an enzyme) is characterized in that the reaction is carried out at a normal temperature and under a normal pressure and has particularly high specificity with respect to substrate (reactant). It is considered that a low loading process of environment harmony type can be constructed by applying the bio-reaction in petroleum refinery process. CO{sub 2} exhaust and energy consumption in the bio-desulfurization (BDS) is estimated to be 70 to 80% lower than those in hydrodesulfurization (HDS). The bio-technologies that can be applied to the petroleum refinery process include, for example, desulfurization, demetallation, dewaxing, denitration, cracking and so on. In this paper, the present state of bio-desulphurization technology is introduced. Particularly, as the research results in Japan, acquirement of mesophile R.erythropolis KA2-5-1 strain, thermophile Paenibacillus sp. A11-2 strain whose optimum temperature is 50 degrees C, BT degradation fungus Rhodococcus sp. T09 and the like are introduced. (NEDO)

Rhodococcus equi: the many facets of a pathogenic actinomycete.

Science.gov (United States)

Vázquez-Boland, José A; Giguère, Steeve; Hapeshi, Alexia; MacArthur, Iain; Anastasi, Elisa; Valero-Rello, Ana

2013-11-29

Rhodococcus equi is a soil-dwelling pathogenic actinomycete that causes pulmonary and extrapulmonary pyogranulomatous infections in a variety of animal species and people. Young foals are particularly susceptible and develop a life-threatening pneumonic disease that is endemic at many horse-breeding farms worldwide. R. equi is a facultative intracellular parasite of macrophages that replicates within a modified phagocytic vacuole. Its pathogenicity depends on a virulence plasmid that promotes intracellular survival by preventing phagosome-lysosome fusion. Species-specific tropism of R. equi for horses, pigs and cattle appears to be determined by host-adapted virulence plasmid types. Molecular epidemiological studies of these plasmids suggest that human R. equi infection is zoonotic. Analysis of the recently determined R. equi genome sequence has identified additional virulence determinants on the bacterial chromosome. This review summarizes our current understanding of the clinical aspects, biology, pathogenesis and immunity of this fascinating microbe with plasmid-governed infectivity. Copyright © 2013 Elsevier B.V. All rights reserved.

Synthesis of novel cyano-cyclitols and their stereoselective biotransformation catalyzed by Rhodococcus erythropolis A4

Czech Academy of Sciences Publication Activity Database

D’Antona, N.; Nicolosi, G.; Morrone, R.; Kubáč, David; Kaplan, Ondřej; Martínková, Ludmila

2010-01-01

Roč. 21, č. 6 (2010), s. 695-702 ISSN 0957-4166 R&D Projects: GA MŠk OC09046 Institutional research plan: CEZ:AV0Z50200510 Keywords : ALICYCLIC NITRILES * ASYMMETRIZATION * HYDROLYSIS Subject RIV: CC - Organic Chemistry Impact factor: 2.484, year: 2010

Individual or synchronous biodegradation of di-n-butyl phthalate and phenol by Rhodococcus ruber strain DP-2

Energy Technology Data Exchange (ETDEWEB)

He, Zhixing; Niu, Chengzhen; Lu, Zhenmei, E-mail: lzhenmei@zju.edu.cn

2014-05-01

Highlights: • A Rhodococcus ruber strain degraded DBP and phenol. • Degradation kinetics of DBP or phenol fit modified first-order models. • Degradation interaction between DBP and phenol was studied by strain DP-2. • The degradation genes transcriptional were quantified by RT-qPCR. - Abstract: The bacterial strain DP-2, identified as Rhodococcus ruber, is able to effectively degrade di-n-butyl phthalate (DBP) and phenol. Degradation kinetics of DBP and phenol at different initial concentrations revealed DBP and phenol degradation to fit modified first-order models. The half-life of DBP degradation ranged from 15.81 to 27.75 h and phenol degradation from 14.52 to 45.52 h under the initial concentrations of 600–1200 mg/L. When strain DP-2 was cultured with a mixture of DBP (800 mg/L) and phenol (700 mg/L), DBP degradation rate was found to be only slightly influenced; however, phthalic acid (PA) accumulated, and phenol degradation was clearly inhibited during synchronous degradation. Transcriptional levels of degradation genes, phenol hydroxylase (pheu) and phthalate 3,4-dioxygenase (pht), decreased significantly more during synchronous degradation than during individual degradation. Quantitative estimation of individual or synchronous degradation kinetics is essential to manage mixed hazardous compounds through biodegradation in industrial waste disposal.

'Wash-out' of Cs-134 and Cs-137 from river sediment; 'Ispiranja' Cs-134 i Cs-137 iz recnog sedimenta

Energy Technology Data Exchange (ETDEWEB)

Skrbic, Z; Conkic, Lj; Bikit, I; Veskovic, M; Slivka, J; Marinkov, L [Institut za Fiziku, Novi Sad Univ. (Yugoslavia)

1988-07-01

Natural elimination and 'wash out' period of the Cs-134 and Cs-137 from the river sediment has been investigated. Obtained results suggest the possibility to describe these processes by exponential low and determination of the corresponding half lives. (author)

Biocatalytic Properties and Structural Analysis of Eugenol Oxidase from Rhodococcus jostii RHA1: A Versatile Oxidative Biocatalyst

OpenAIRE

Nguyen, Quoc-Thai; de Gonzalo, Gonzalo; Binda, Claudia; Rioz-Martínez, Ana; Mattevi, Andrea; Fraaije, Marco W.

2016-01-01

Abstract Eugenol oxidase (EUGO) from Rhodococcus jostii RHA1 had previously been shown to convert only a limited set of phenolic compounds. In this study, we have explored the biocatalytic potential of this flavoprotein oxidase, resulting in a broadened substrate scope and a deeper insight into its structural properties. In addition to the oxidation of vanillyl alcohol and the hydroxylation of eugenol, EUGO can efficiently catalyze the dehydrogenation of various phenolic ketones and the selec...

Uptake and distribution of 137Cs, stable Cs and K in rice plants

International Nuclear Information System (INIS)

Tsukada, Hirofumi; Hasegawa, Hidenao

2003-01-01

The uptake and distributions of 137 Cs, stable Cs and K were determined for rice plant components, including polished rice, rice bran, hulls, leaves, stems, and roots. The distribution of 137 Cs in polished rice and rice bran was similar to that of stable Cs, while that of K was different. The concentration ratios of Cs/K in leaves increased in older leaf blade positions, which meant that the translocation rate of stable Cs, was slower than that of K. At harvest the dry weight of polished rice accounted for 34% of the entire rice plant, while the distributions of stable Cs in the polished rice and the non-edible parts were 7 and 93%, respectively. These findings suggest that the transfer and distribution of stable Cs in rice plants are different from those of K, and the behavior of stable Cs provides a useful analogue in predicting the fate of 137 Cs in an agricultural environment. (author)

vanO, a new glycopeptide resistance operon in environmental Rhodococcus equi isolates

DEFF Research Database (Denmark)

Gudeta, Dereje Dadi; Moodley, Arshnee; Bortolaia, Valeria

2014-01-01

We describe sequence and gene organization of a new glycopeptide resistance operon (vanO) in Rhodococcus equi from soil. The vanO operon has low homology to enterococccal van operons and harbors a vanHOX cluster transcribed in opposite direction to the vanS-vanR regulatory system and comprised be...... between three open reading frames with unknown function. This finding has clinical interest since glycopeptides are used to treat R. equi infections and resistance has been reported in clinical isolates....

135Cs activity and 135Cs/137Cs atom ratio in environmental samples before and after the Fukushima Daiichi Nuclear Power Plant accident.

Science.gov (United States)

Yang, Guosheng; Tazoe, Hirofumi; Yamada, Masatoshi

2016-04-07

(135)Cs/(137)Cs is a potential tracer for radiocesium source identification. However, due to the challenge to measure (135)Cs, there were no (135)Cs data available for Japanese environmental samples before the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. It was only 3 years after the accident that limited (135)Cs values could be measured in heavily contaminated environmental samples. In the present study, activities of (134)Cs, (135)Cs, and (137)Cs, along with their ratios in 67 soil and plant samples heavily and lightly contaminated by the FDNPP accident were measured by combining γ spectrometry with ICP-MS/MS. The arithmetic means of the (134)Cs/(137)Cs activity ratio (1.033 ± 0.006) and (135)Cs/(137)Cs atom ratio (0.334 ± 0.005) (decay corrected to March 11, 2011), from old leaves of plants collected immediately after the FDNPP accident, were confirmed to represent the FDNPP derived radiocesium signature. Subsequently, for the first time, trace (135)Cs amounts before the FDNPP accident were deduced according to the contribution of global and FDNPP accident-derived fallout. Apart from two soil samples with a tiny global fallout contribution, contributions of global fallout radiocesium in other soil samples were observed to be 0.338%-52.6%. The obtained (135)Cs/(137)Cs database will be useful for its application as a geochemical tracer in the future.

Activity standardization of 134Cs and 137Cs

International Nuclear Information System (INIS)

Sochorová, Jana; Auerbach, Pavel

2014-01-01

The paper presents the results from a primary standardization of 137 Cs using two independent methods – efficiency tracing using PC-NaI coincidence and the TDCR method. The nuclides 60 Co and 134 Cs were used as the tracers. Primary standardization of the 134 Cs is also discussed. The efficiency extrapolation was carried out by measuring samples of varying mass and using the wet extrapolation method. The results obtained are in good agreement; the differences did not exceed 0.5%. The advantages, pitfalls and also possibilities for improvement of the procedures are discussed

Determination of Cs-134 and Cs-137 rain water samples

International Nuclear Information System (INIS)

Lima, M.F.; Mazzilli, B.

1988-01-01

In order to setting an environmental monitoring program at IPEN, was developed a fast and simple methodology for concentration of Cs-134 and Cs-137 in rain water. This procedure consists in the precipitation of cesium and others cathions of its family (NH 4 + , K + and Rb + ) by ammonium molybdophosphate. The measures of the desintegration rates of Cs-134 and Cs-137 was done by gamma spectrometry in a Ge(Li) detector. After setting up the ideal experimental conditions, the procedure was used to analyze four samples of rain water. (author) [pt

Determination of {sup 135}Cs and {sup 137}Cs in environmental samples: A review

Energy Technology Data Exchange (ETDEWEB)

Russell, B.C., E-mail: ben.russell@npl.co.uk [GAU-Radioanalytical, Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH (United Kingdom); National Physical Laboratory, Hampton Road, Teddington, Middlesex, TW11 0LW (United Kingdom); Croudace, Ian W.; Warwick, Phil E. [GAU-Radioanalytical, Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH (United Kingdom)

2015-08-26

Radionuclides of caesium are environmentally important since they are formed as significant high yield fission products ({sup 135}Cs and {sup 137}Cs) and activation products ({sup 134}Cs and {sup 136}Cs) during nuclear fission. They originate from a range of nuclear activities such as weapons testing, nuclear reprocessing and nuclear fuel cycle discharges and nuclear accidents. Whilst {sup 137}Cs, {sup 134}Cs and {sup 136}Cs are routinely measurable at high sensitivity by gamma spectrometry, routine detection of long-lived {sup 135}Cs by radiometric methods is challenging. This measurement is, however, important given its significance in long-term nuclear waste storage and disposal. Furthermore, the {sup 135}Cs/{sup 137}Cs ratio varies with reactor, weapon and fuel type, and accurate measurement of this ratio can therefore be used as a forensic tool in identifying the source(s) of nuclear contamination. The shorter-lived activation products {sup 134}Cs and {sup 136}Cs have a limited application but provide useful early information on fuel irradiation history and have importance in health physics. Detection of {sup 135}Cs (and {sup 137}Cs) is achievable by mass spectrometric techniques; most commonly inductively coupled plasma mass spectrometry (ICP-MS), as well as thermal ionisation (TIMS), accelerator (AMS) and resonance ionisation (RIMS) techniques. The critical issues affecting the accuracy and detection limits achievable by this technique are effective removal of barium to eliminate isobaric interferences arising from {sup 135}Ba and {sup 137}Ba, and elimination of peak tailing of stable {sup 133}Cs on {sup 135}Cs. Isobaric interferences can be removed by chemical separation, most commonly ion exchange chromatography, and/or instrumental separation using an ICP-MS equipped with a reaction cell. The removal of the peak tailing interference is dependent on the instrument used for final measurement. This review summarizes and compares the analytical procedures

Radioactive Cs in the Severely Contaminated Soils Near the Fukushima Daiichi Nuclear Power Plant

Energy Technology Data Exchange (ETDEWEB)

Kaneko, Makoto; Iwata, Hajime; Shiotsu, Hiroyuki; Masaki, Shota; Kawamoto, Yuji; Yamasaki, Shinya; Nakamatsu, Yuki; Imoto, Junpei; Furuki, Genki; Ochiai, Asumi [Department of Chemistry, Kyushu University, Fukuoka (Japan); Nanba, Kenji [Department of Environmental Management, Faculty of Symbiotic System Science, Fukushima University, Fukushima (Japan); Ohnuki, Toshihiko [Advanced Science Research Center Japan Atomic Energy Agency, Tokai (Japan); Ewing, Rodney C. [Department of Geological Sciences, Center for International Security and Cooperation, Stanford University, Stanford, CA (United States); Utsunomiya, Satoshi, E-mail: utsunomiya.satoshi.998@m.kyushu-u.ac.jp [Department of Chemistry, Kyushu University, Fukuoka (Japan)

2015-09-01

Radioactive Cs isotopes ({sup 137}Cs, t{sub 1/2} = 30.07 years and {sup 134}Cs, t{sub 1/2} = 2.062 years) occur in severely contaminated soils within a few kilometer of the Fukushima Daiichi nuclear power plant at concentrations that range from 4 × 10{sup 5} to 5 × 10{sup 7} Bq/kg. In order to understand the mobility of Cs in these soils, both bulk and submicron-sized particles elutriated from four surface soils have been investigated using a variety of analytical techniques, including powder X-ray diffraction analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and analysis of the amount of radioactivity in sequential chemical extractions. Major minerals in bulk soil samples were quartz, feldspar, and minor clays. The submicron-sized particles elutriated from the same soil consist mainly of mica, vermiculite, and smectite and occasional gibbsite. Autoradiography in conjunction with SEM analysis confirmed the association of radioactive Cs mainly with the submicron-sized particles. Up to ~3 MBq/kg of {sup 137}Cs are associated with the colloidal size fraction (<1 μm), which accounts for ~78% of the total radioactivity. Sequential extraction of the bulk sample revealed that most Cs was retained in the residual fraction, confirming the high binding affinity of Cs to clays, aluminosilicate sheet structures. The chemistry of the fraction containing submicron-sized particles from the same bulk sample showed a similar distribution to that of the bulk sample, again confirming that the Cs is predominantly adsorbed onto submicron-sized sheet aluminosilicates, even in the bulk soil samples. Despite the very small particle size, aggregation of the particles prevents migration in the vertical direction, resulting in the retention of >98% of Cs within top ~5 cm of the soil. These results suggest that the mobility of the aggregates of submicron-sized sheet aluminosilicate in the surface environment is a key factor controlling the current Cs

The effective and environmental half-life of 137Cs at Coral Islands at the former US nuclear test site

International Nuclear Information System (INIS)

Robison, William L.; Conrado, Cynthia L.; Bogen, Kenneth T.; Stoker, A. Carol

2003-01-01

The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 ( 137 Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of 137 Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of 137 Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of 137 Cs and 90 Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of 137 Cs and 90 Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of 137 Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the 137 Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the 137 Cs/ 90 Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the 137 Cs/ 90 Sr ratios in soil in 1987 relative to the 137 Cs/ 90 Sr ratios at the time of deposition in 1954 is less than 17 years. The magnitude of the decrease below 17 years depends on

The effective and environmental half-life of 137Cs at Coral Islands at the former US nuclear test site.

Science.gov (United States)

Robison, William L; Conrado, Cynthia L; Bogen, Kenneth T; Stoker, A Carol

2003-01-01

The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 (137Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of 137Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of 137Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of 137Cs and 90Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of 137Cs and 90Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of 137Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the 137Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the 137Cs/90Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the 137Cs/90Sr ratios in soil in 1987 relative to the 137Cs/90Sr ratios at the time of deposition in 1954 is less than 17 years. The magnitude of the decrease below 17 years depends on the ELH for 90Sr

Structure of the virulence-associated protein VapD from the intracellular pathogen Rhodococcus equi

International Nuclear Information System (INIS)

Whittingham, Jean L.; Blagova, Elena V.; Finn, Ciaran E.; Luo, Haixia; Miranda-CasoLuengo, Raúl; Turkenburg, Johan P.; Leech, Andrew P.; Walton, Paul H.; Murzin, Alexey G.; Meijer, Wim G.; Wilkinson, Anthony J.

2014-01-01

VapD is one of a set of highly homologous virulence-associated proteins from the multi-host pathogen Rhodococcus equi. The crystal structure reveals an eight-stranded β-barrel with a novel fold and a glycine rich ‘bald’ surface. Rhodococcus equi is a multi-host pathogen that infects a range of animals as well as immune-compromised humans. Equine and porcine isolates harbour a virulence plasmid encoding a homologous family of virulence-associated proteins associated with the capacity of R. equi to divert the normal processes of endosomal maturation, enabling bacterial survival and proliferation in alveolar macrophages. To provide a basis for probing the function of the Vap proteins in virulence, the crystal structure of VapD was determined. VapD is a monomer as determined by multi-angle laser light scattering. The structure reveals an elliptical, compact eight-stranded β-barrel with a novel strand topology and pseudo-twofold symmetry, suggesting evolution from an ancestral dimer. Surface-associated octyl-β-d-glucoside molecules may provide clues to function. Circular-dichroism spectroscopic analysis suggests that the β-barrel structure is preceded by a natively disordered region at the N-terminus. Sequence comparisons indicate that the core folds of the other plasmid-encoded virulence-associated proteins from R. equi strains are similar to that of VapD. It is further shown that sequences encoding putative R. equi Vap-like proteins occur in diverse bacterial species. Finally, the functional implications of the structure are discussed in the light of the unique structural features of VapD and its partial structural similarity to other β-barrel proteins

Structure of the virulence-associated protein VapD from the intracellular pathogen Rhodococcus equi

Energy Technology Data Exchange (ETDEWEB)

Whittingham, Jean L.; Blagova, Elena V. [University of York, Heslington, York YO10 5DD (United Kingdom); Finn, Ciaran E.; Luo, Haixia; Miranda-CasoLuengo, Raúl [University College Dublin, Dublin (Ireland); Turkenburg, Johan P.; Leech, Andrew P.; Walton, Paul H. [University of York, Heslington, York YO10 5DD (United Kingdom); Murzin, Alexey G. [MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH (United Kingdom); Meijer, Wim G. [University College Dublin, Dublin (Ireland); Wilkinson, Anthony J., E-mail: tony.wilkinson@york.ac.uk [University of York, Heslington, York YO10 5DD (United Kingdom)

2014-08-01

VapD is one of a set of highly homologous virulence-associated proteins from the multi-host pathogen Rhodococcus equi. The crystal structure reveals an eight-stranded β-barrel with a novel fold and a glycine rich ‘bald’ surface. Rhodococcus equi is a multi-host pathogen that infects a range of animals as well as immune-compromised humans. Equine and porcine isolates harbour a virulence plasmid encoding a homologous family of virulence-associated proteins associated with the capacity of R. equi to divert the normal processes of endosomal maturation, enabling bacterial survival and proliferation in alveolar macrophages. To provide a basis for probing the function of the Vap proteins in virulence, the crystal structure of VapD was determined. VapD is a monomer as determined by multi-angle laser light scattering. The structure reveals an elliptical, compact eight-stranded β-barrel with a novel strand topology and pseudo-twofold symmetry, suggesting evolution from an ancestral dimer. Surface-associated octyl-β-d-glucoside molecules may provide clues to function. Circular-dichroism spectroscopic analysis suggests that the β-barrel structure is preceded by a natively disordered region at the N-terminus. Sequence comparisons indicate that the core folds of the other plasmid-encoded virulence-associated proteins from R. equi strains are similar to that of VapD. It is further shown that sequences encoding putative R. equi Vap-like proteins occur in diverse bacterial species. Finally, the functional implications of the structure are discussed in the light of the unique structural features of VapD and its partial structural similarity to other β-barrel proteins.

Both epiphytic and endophytic strains of Rhodococcus fascians influence transporter gene expression and cytokinins in infected Pisum sativum L. seedlings

Czech Academy of Sciences Publication Activity Database

Dhandapani, P.; Song, J.; Novák, Ondřej; Jameson, P. E.

2018-01-01

Roč. 85, č. 2 (2018), s. 231-242 ISSN 0167-6903 R&D Projects: GA ČR(CZ) GA17-06613S Institutional support: RVO:61389030 Keywords : Amino acid transporter * Cell wall invertase * Cytokinin * Pea * Rhodococcus fascians * Sucrose transporter * Sugar Will Eventually be Exported Transporter (SWEET) Subject RIV: EF - Botanics OBOR OECD: Plant sciences, botany Impact factor: 2.646, year: 2016

Serological survey of Rhodococcus equi infection in horses in Hokkaido.

Science.gov (United States)

Sanada, Y; Noda, H; Nagahata, H

1992-08-01

Serological survey of Rhodococcus equi infection in horses in Hokkaido was performed using ELISA. Of 2,879 horse sera, 318 (11.0%) gave antibody-positive (OD greater than or equal to 0.3) reactions. The antibody-positive rate of female was significantly higher (p less than 0.01) than that of male, and no statistical difference between Anglo-Arab and thoroughbred was detected in the antibody-positive rate. The maximum antibody-positive rate (27.1%) was shown at 14 years of age. The antibody-positive rates on the 160 farms were found to vary widely from 0 to 78.9%. A significant difference (p less than 0.01) in the antibody-positive rate was detected among horse farms. It was elucidated that 100 (62.5%) out of 160 horse farms had an antibody-positive horse. These results indicate that R. equi was widespread on horse farms, and the level of environmental contamination with R. equi differed among horse farms.

Biodegradation of Di-(2-ethylhexyl) Phthalate by Rhodococcus ruber YC-YT1 in Contaminated Water and Soil

OpenAIRE

Ting Yang; Lei Ren; Yang Jia; Shuanghu Fan; Junhuan Wang; Jiayi Wang; Ruth Nahurira; Haisheng Wang; Yanchun Yan

2018-01-01

Di-(2-ethylehxyl) phthalate (DEHP) is one of the most broadly representative phthalic acid esters (PAEs) used as a plasticizer in polyvinyl chloride (PVC) production, and is considered to be an endocrine-disrupting chemical. DEHP and its monoester metabolites are responsible for adverse effects on human health. An efficient DEHP-degrading bacterial strain Rhodococcus ruber YC-YT1, with super salt tolerance (0–12% NaCl), is the first DEHP-degrader isolated from marine plastic debris found in c...

[Cloning and expression of Micrococcus luteus IAM 14879 Rpf and its role in the recovery of the VBNC state in Rhodococcus sp. DS471].

Science.gov (United States)

Ding, Linxian; Zhang, Pinghua; Hong, Huachang; Lin, Hongjun; Yokota, Akira

2012-01-01

The purpose of the present study was to produce the Rpf (resuscitation promoting factor) protein by cloning and expressing the rpf gene, secreted by Micrococcus luteus IAM 14879, in Escherichia coli and to evaluate its role in the recovery of the VBNC (viable but non-culturable) state in high-GC Gram-positive bacteria. Genomic DNA was extracted from Micrococcus luteus IAM 14879 and the rpf gene was amplified by PCR using specific primers. The PCR products was purified, cloned into a pET15b expression vector, and transformed into Escherichia coli BL21 (DE3). Then the pET15b plasmid expression vector was used to confirm the purification of the recombinant proteins via SDS-PAGE. The VBNC state cells from the high-GC Gram-positive bacteria, Rhodococcus sp. DS471, were used to confirm the promotion and recovery of growth capacity. Rhodococcus sp. DS471 were isolated from soil and closely related to Micrococcus luteus IAM 14879. The gene sequences confirmed that the rpf gene from Micrococcus luteus IAM 14879 that was expressed in Escherichia coli, was 672 bp. SDS-PAGE analysis showed that the recombinant Rpf protein was obtained successfully, and further studies showed it capable of promoting the recovery of the VBNC state by about 100-fold relative to the control. Rpf of Micrococus luteus IAM 14879 can be successfully cloned and expressed in Escherichia coli and shows a strong ability to promote the recovery of the VBNC state of cells of Rhodococcus sp. DS471.

Improving CS regulations.

Energy Technology Data Exchange (ETDEWEB)

Nesse, R.J.; Scheer, R.M.; Marasco, A.L.; Furey, R.

1980-10-01

President Carter issued Executive Order 12044 (3/28/78) that required all Federal agencies to distinguish between significant and insignificant regulations, and to determine whether a regulation will result in major impacts. This study gathered information on the impact of the order and the guidelines on the Office of Conservation and Solar Energy (CS) regulatory practices, investigated problems encountered by the CS staff when implementing the order and guidelines, and recommended solutions to resolve these problems. Major tasks accomplished and discussed are: (1) legislation, Executive Orders, and DOE Memoranda concerning Federal administrative procedures relevant to the development and analysis of regulations within CS reviewed; (2) relevant DOE Orders and Memoranda analyzed and key DOE and CS staff interviewed in order to accurately describe the current CS regulatory process; (3) DOE staff from the Office of the General Counsel, the Office of Policy and Evaluation, the Office of the Environment, and the Office of the Secretary interviewed to explore issues and problems encountered with current CS regulatory practices; (4) the regulatory processes at five other Federal agencies reviewed in order to see how other agencies have approached the regulatory process, dealt with specific regulatory problems, and responded to the Executive Order; and (5) based on the results of the preceding four tasks, recommendations for potential solutions to the CS regulatory problems developed. (MCW)

Radiation damage in undoped CsI and CsI(Tl)

International Nuclear Information System (INIS)

Woody, C.L.; Kierstead, J.A.; Levy, P.W.; Stoll, S.

1992-01-01

Radiation damage has been studied in undoped CsI and CsI(TI) crystals using 60 Co gamma radiation for doses up to ∼ 4.2 x 10 6 . Samples from various manufacturers were measured ranging in size from 2.54 cm long cylinders to a 30 cm long block. Measurements were made on the change in optical transmission and scintillation light output as a function of dose. Although some samples showed a small change in transmission, a significant change in light output was observed for all samples. Recovery from damage was also studied as a function of time and exposure to UV light. A short lived phosphorescence was observed in undoped CsI, similar to the phosphorescence seen in CsI(TI)

Regeneration of Used Frying Palm Oil with Coffee Silverskin (CS), CS Ash (CSA) and Nanoparticles of CS (NCS).

Science.gov (United States)

Ismail, Samir Abd-Elmonem A; El-Anany, Ayman Mohammed; Ali, Rehab Farouk M

2017-01-01

The present investigation aimed to evaluate the efficiency of coffee silverskin (CS), CS ash (CSA) and nanoparticles of CS (NCS) in regeneration the quality of used frying palm oil. The adsorbents were mixed individually with used frying palm oil at level 4% (w/v) for 60 min. The properties of CS, CSA and NCS adsorbents were studied using (SEM) scanning electron microscopy technique. Some of physico-chemical characteristics of used frying palm oil (UFPO) and UFPO treated with adsorbents were determined. The results showed that the CS ash particles composed of irregular spherical and semispherical grains with deep cavities. The size of particles of CS ash ranged in diameter from 1.1 to 1.7 µm. The morphology of NCS consisted of cluster-type spherical nanoparticles and flakes. The particle size of NCS varies from 0.9 to 1.7 µm. Purification treatments caused marked (poil compared to untreated oil. The treatment of UFPO with 4% of adsorbents caused significant reductions in the content of free fatty acids ranged from 51.2 to 65.0%. The lowest level of peroxide (2.1 meq/kg) was recorded for UFPO treated with 4% of NCS. The highest reductions (72.8; 70.0%) in p-anisidine value were observed in UFPO treated with 4% of CSA and NCS, respectively. Treatment of UFPO with 4% of CS, CSA and NCS significantly lowered the polar content from 13.9% to 6.3, 4.8 and 3.9%, respectively. The results also indicate that CSA and NCS have nearly the same adsorption efficiency in lowering polymer content of UFPO. Filtration treatment of UFPO with 4% of CS, CSA and NCS markedly lowered the viscosity and colour values of treated UFPO.

Properties of CsI and CsI-TMAE photocathodes

International Nuclear Information System (INIS)

Anderson, D.F.; Kwan, S.; Peskov, V.; Hoeneisen, B.

1992-06-01

The importance of heating the CsI or CsI-TMAE photocathodes during preparation, as well as the importance of the gas environment on the quantum efficiency is presented. The dependence of the aging characteristics of these photocathodes on the operating temperature, on the presence of gas, and on the charge amplification of the chamber is also discussed. For CsI photocathodes charges in excess of 2x10 14 e - /mm 2 can be collected with little degradation of performance. A timing resolution of 0.55 ns is also achieved for single photoelectrons suggesting a possible time-of-flight detector

Identificação diferencial de Rhodococcus equi e Dietzia maris em bubalinos Differential identification of Rhodococcus equi and Dietzia maris in buffaloes

Directory of Open Access Journals (Sweden)

L.R. Viana

2009-08-01

Full Text Available Foram analisados 24 isolados bacterianos oriundos de leite e pele de búfalas (Bubalus bubalis, os quais foram previamente identificados como Rhodococcus equi com o auxílio de fenotipia concisa. Testes fenotípicos complementares e ferramentas moleculares foram utilizados com o objetivo de caracterizar esses isolados, bem como diferenciá-los de outros microrganismos intimamente relacionados. Observaram-se três fenótipos distintos, porém a identificação dos isolados foi inconclusiva. Apenas um dos isolados foi comprovado como sendo R. equi com a realização da PCR espécie-específica, sequenciamento e análise dos fragmentos de DNA. Os demais isolados só foram identificados pelo sequenciamento de fragmento do gene que codifica a região 16S do rRNA universal de bactérias, indicando tratar-se de Dietzia maris. O perfil de susceptibilidade aos antimicrobianos revelou maior resistência dos isolados de D. maris para oxacilina (96% e rifampicina (87%. O isolado de R. equi apresentou resistência à amicacina, oxacilina, penicilina, rifampicina e tetraciclina. Alerta-se para o risco da incorreta identificação dos isolados baseados em testes fenotípicos concisos e para a necessidade de utilização de testes complementares para diferenciação entre R. equi e D. maris.Twenty-four bacterial isolates from milk and skin of buffalo females (Bubalus bubalis, which previously had been identified as Rhodococcus equi by using a restricted number of phenotypical tests for bacterial characterization, were analyzed. The goal of this study was to perform the characterization of these isolates, as well as the differentiation of other microorganisms closely related by using additional phenotypical tests and molecular tools. Based on the phenotypical results, three different biotypes were obtained. However, the identification of the isolates was inconclusive. Only one of the isolates was confirmed as R. equi by the PCR specifically for this species, as

Induction of leafy galls in Acacia mearnsii De Wild seedlings infected by Rhodococcus fascians

Directory of Open Access Journals (Sweden)

Marguerite Quoirin

2004-07-01

Full Text Available Plantlets of blackwattle (Acacia mearnsii De Wild were inoculated with the bacterium Rhodococcus fascians and cultured in vitro. Leafy galls appeared at the cotyledonary nodes in 75% of the infected plants. The galls were separated from the plants and cultured on a medium containing three-quarters-strength MS salts (Murashige and Skoog, 1962, MS vitamins, 2% sucrose and an antibiotic (cephalothin, supplemented with or without 0.2% activated charcoal. Histological studies conducted from the sixth to the twenty-second day after plant infection revealed the presence of newly formed meristematic centers, first in the axillary region, then on the petioles and lamina of the leaflets around the apical meristem. Approximately 37% of the galls developed one shoot with both concentrations of cephalothin.Plantas recém germinadas de acácia negra (Acacia mearnsii De Wild. foram inoculadas com a bactéria Rhodococcus fascians e cultivadas in vitro. Galhas cobertas por folhas apareceram na altura do nó cotiledonar em 75% das plantas infectadas. As galhas foram separadas das plantas e cultivadas num meio de cultura contendo os sais do meio MS (Murashige e Skoog, 1962 reduzidos a 3/4, as vitaminas do mesmo meio, 2% de sacarose e um antibiótico (cefalotina, adicionado ou não de 0,2% de carvão ativo. Estudos histológicos realizados entre o sexto e o vigésimo segundo dia depois da inoculação, revelaram a presença de centros meristemáticos novos, primeiro nas regiões axilares, em seguida nos pecíolos e limbos dos folíolos ao redor do meristema apical. Aproximadamente 37% das galhas desenvolveram um broto na presença de cefalotina.

Concentration of 134Cs and 137Cs in Malaysian palm products

International Nuclear Information System (INIS)

Yii Mei Wo; Nor Aza Hassan; Narizan Sanusi

2008-08-01

Until today, countries importing food products from Malaysia, in region such as Indian Continental, Middle East, Central Europe and Central America still require the products to be tested for the radioactive contamination particularly for 134 Cs and 137 Cs. Information extracted from 3371 analytical results observed on isotopic concentration for 134 Cs and 137 Cs in the exported Malaysia origins palm products between years 2002 until 2007 had been summarized and reported in this work. Data shown that the concentration level of the concerned radio nuclides are below the minimum detectable activity and also well below maximum permissible limits adopted by Malaysian Government and also the international bodies. (Author)

Separation of 134Cs and 137Cs from 125I solution for medical applications

International Nuclear Information System (INIS)

Ram, Ramu; Dash, Ashutosh; Banerjee, Dayamoy

2015-01-01

While neutron irradiation of natural Xe gas followed by wet chemical dissolution of activation products constitutes a successful paradigm for the small scale production 125 I, the concomitant production of 134 Cs and 137 Cs emerged as the primary impediment which necessitates purification of 125 I solution. This paper describes an ion-exchange chromatographic technique using Resorcinol Formaldehyde (RF) resin to purify 125 I solution from 134 Cs and 137 Cs impurities. A thorough investigation of the adsorption parameters of RF resin was carried out to arrive at the experimental conditions resulting optimum retention of 134 Cs and 137 Cs impurities. Based on the experimental findings, an optimized separation procedure was developed in which the neutron irradiated dissolved products at pH ∝ 13 was passed through a chromatography column containing RF resin where in 134 Cs and 137 Cs impurities gets adsorbed leaving behind 125 I to appear in the effluent. The overall recovery of 125 I was >90% with acceptable purity amenable for clinical applications.

APPLICATION OF PSEUDOMONAS PUTIDA AND RHODOCOCCUS SP. BY BIODEGRADATION OF PAH(S, PCB(S AND NEL SOIL SAMPLES FROM THE HAZARDOUS WASTE DUMP IN POZĎÁTKY (CZECH REPUBLIC

Directory of Open Access Journals (Sweden)

Radmila Kucerova

2006-12-01

Full Text Available The objective of the project was a laboratory check of biodegradation of soil samples contaminated by PAH(s, PCB(s and NEL from the hazardous waste dump in the Pozďátky locality. For the laboratory check, pure bacterial cultures of Rhodococcus sp. and Pseudomonas putida have been used. It is apparent from the laboratory experiments results that after one-month bacterial leaching, applying the bacterium of Rhodococcus sp. there is a 83 % removal of NEL, a 79 % removal of PAH(s and a 14 % removal of PCB(s. Applying a pure culture of Pseudomonas putida there is a 87 % removal of NEL, a 81 % removal of PAH(s and a 14 % removal of PCB(s.

Successful bioaugmentation of an activated sludge reactor with Rhodococcus sp. YYL for efficient tetrahydrofuran degradation

International Nuclear Information System (INIS)

Yao, Yanlai; Lu, Zhenmei; Zhu, Fengxiang; Min, Hang; Bian, Caimiao

2013-01-01

Highlights: • Rhodococcus sp. YYL is an efficient tetrahydrofuran-degrading strain. • Strain YYL was used to augment an activated sludge system for THF degradation. • Successful bioaugmentation was achieved only by coinoculation of strain YYL and the two bacilli. • Successful bioaugmentation of the system resulted in efficient THF degradation. -- Abstract: The exchange of tetrahydrofuran (THF)-containing wastewater should significantly affect the performance of an activated sludge system. In this study, the feasibility of using THF-degrading Rhodococcus sp. strain YYL to bioaugment an activated sludge system treating THF wastewater was explored. As indicated by a DGGE analysis, strain YYL alone could not dominate the system, with the concentration of mixed liquor suspended solids (MLSS) decreasing to nearly half of the initial concentration after 45 d, and the microbial diversity was found to be significantly reduced. However, after the reactor was augmented with the mixed culture of strain YYL and two bacilli initially coexisting in the enriched isolation source, strain YYL quickly became dominant in the system and was incorporated into the activated sludge. The concentration of MLSS increased from 2.1 g/L to 7.3 g/L in 20 d, and the efficiency of THF removal from the system was remarkably improved. After the successful bioaugmentation, more than 95% of THF was completely removed from the wastewater when 20 mM THF was continuously loaded into the system. In conclusion, our research first demonstrates that bioaugmentation of activated sludge system for THF degradation is feasible but that successful bioaugmentation should utilize a THF-degrading mixed culture as the inoculum, in which the two bacilli might help strain YYL colonize in activated sludge by co-aggregation

[Energy pooling collisions for K(4P) + Cs(5D) in a K-Cs mixture].

Science.gov (United States)

Aihemaiti, Pulati; Dai, Kang; Lu, Xin-hong; Shen, Yi-fan

2005-04-01

The rate coefficients for energy-pooling collisions K(4P) + Cs(5D) --> Cs(6S) + K(4D, 6S) in the K-Cs vapor mixture were measured relative to a known energy-pooling rate coefficient of a homonuclear reaction [i. e., Cs(6P) + Cs(5D) --> Cs(6S) + Cs (7D(J))]. Populations of the Cs(6P, 5D) and K(4P) states were produced by photodissociation of K2 and Cs2 molecules through the use of a dye laser radiation. The resulting fluorescence included the direct components emitted in the decay of the excited states produced by photodissociation and the induced components arising from the collisionally populated states. By combining relative intensities of the components with the effective lifetimes of Cs(6P) and K(4P) states, the rate coefficients (in units of 10(-9) cm3 x s(-1)) for the heteronuclear energy-pooling were found to be 2.6 and 3.6, respectively. The contribution to the rate coefficients from other processes are discussed.

Biotechnological methods for chalcone reduction using whole cells of Lactobacillus, Rhodococcus and Rhodotorula strains as a way to produce new derivatives.

Science.gov (United States)

Stompor, Monika; Kałużny, Mateusz; Żarowska, Barbara

2016-10-01

Microbial strains of the genera Dietzia, Micrococcus, Pseudomonas, Rhodococcus, Gordonia, Streptomyces, Pseudomonas, Bacillus, Penicillium, Rhodotorula and Lactobacillus were screened for the ability to convert chalcones. Synthesis of chalcones was performed by the Claisen-Schmidt reaction. There were three groups of chalcones obtained as the products, which included the derivatives containing 4-substituted chalcone, 2'-hydroxychalcone and 4'-methoxychalcone. The B ring of the chalcones was substituted in the para position with different groups, such as halide, hydroxyl, nitro, methyl, ethyl and ethoxy one. The structure-activity relationship of the tested chalcones in biotransformation processes was studied. It has been proven that Gram-positive bacterial strains Rhodococcus and Lactobacillus catalyzed reduction of C=C bond in the chalcones to give respective dihydrochalcones. The strain Rhodotorula rubra AM 82 transformed chalcones into dihydrochalcones and respective secondary alcohols. These results suggest that the probiotic strain of Lactobacillus can be used for biotransformations of chalcones, which has not been described before. The structure of new metabolites 14a and 15b were established as 4-ethoxy-4'-methoxydihydrochalcone and 3-(4-bromophenyl)-1-(4'-O-methylphenyl)-2-propan-1-ol, respectively, which was confirmed by (1)H NMR and (13)C NMR analysis.

Characterization of Virulence Plasmids and Serotyping of Rhodococcus equi Isolates from Submaxillary Lymph Nodes of Pigs in Hungary

OpenAIRE

Makrai, László; Takayama, Saki; Dénes, Béla; Hajtós, István; Sasaki, Yukako; Kakuda, Tsutomu; Tsubaki, Shiro; Major, Andrea; Fodor, László; Varga, János; Takai, Shinji

2005-01-01

The plasmid types and serotypes of 164 Rhodococcus equi strains obtained from submaxillary lymph nodes of swine from different piggeries in 28 villages and towns located throughout the country were examined. The strains were tested by PCR for the presence of 15- to 17-kDa virulence-associated protein antigen (VapA) and 20-kDa virulence-associated protein antigen (VapB) genes. Plasmid DNAs were isolated and analyzed by digestion with restriction endonucleases to estimate size and compare their...

Changing US Attributes After CS-US Pairings Changes CS-Attribute-Assessments: Evidence for CS-US Associations in Attribute Conditioning.

Science.gov (United States)

Förderer, Sabine; Unkelbach, Christian

2016-03-01

Attribute Conditioning (AC) refers to people's changed assessments of stimuli's (CSs) attributes due to repeated pairing with stimuli (USs) possessing these attributes; for example, when an athletic person (US) is paired with a neutral person (CS), the neutral person is judged to be more athletic after the pairing. We hypothesize that this AC effect is due to CSs' associations with USs rather than direct associations with attributes. Three experiments test this hypothesis by changing US attributes after CS-US pairings. Experiments 1 and 2 conditioned athleticism by pairing neutral men (CSs) with athletic and non-athletic USs. Post-conditioning, USs' athleticism was reversed, which systematically influenced participants' assessment of CS athleticism. Experiment 3 conditioned athleticism and changed USs' musicality after CS-US pairings. This post-conditioning change affected musicality assessments of CSs but did not influence athleticism-assessments. The results indicate that AC effects are based on an associative CS-US-attribute structure. © 2016 by the Society for Personality and Social Psychology, Inc.

A novel vanadosilicate with hexadeca-coordinated Cs+ ions as a highly effective Cs+ remover

International Nuclear Information System (INIS)

Datta, Shuvo Jit; Moon, Won Kyung; Choi, Do Young; Hwang, In Chul; Yoon, Kyung Byung

2014-01-01

The effective removal of 137 Cs + ions from contaminated groundwater and seawater and from radioactive nuclear waste solutions is crucial for public health and for the continuous operation of nuclear power plants. Various 137 Cs + removers have been developed, but more effective 137 Cs + removers are still needed. A novel microporous vanadosilicate with mixed-valence vanadium (V 4+ and V 5+ ) ions is now reported, which shows an excellent ability for Cs + capture and immobilization from groundwater, seawater, and nuclear waste solutions. This material is superior to other known materials in terms of selectivity, capacity, and kinetics, and at very low Cs + concentrations, it was found to be the most effective material for the removal of radioactive Cs + ions under the test conditions. This novel vanadosilicate also contains hexadeca-coordinated Cs + ions, which corresponds to the highest coordination number ever described.

Hybridization of Single Nanocrystals of Cs4PbBr6 and CsPbBr3.

Science.gov (United States)

Weerd, Chris de; Lin, Junhao; Gomez, Leyre; Fujiwara, Yasufumi; Suenaga, Kazutomo; Gregorkiewicz, Tom

2017-09-07

Nanocrystals of all-inorganic cesium lead halide perovskites (CsPbX 3 , X = Cl, Br, I) feature high absorption and efficient narrow-band emission which renders them promising for future generation of photovoltaic and optoelectronic devices. Colloidal ensembles of these nanocrystals can be conveniently prepared by chemical synthesis. However, in the case of CsPbBr 3 , its synthesis can also yield nanocrystals of Cs 4 PbBr 6 and the properties of the two are easily confused. Here, we investigate in detail the optical characteristics of simultaneously synthesized green-emitting CsPbBr 3 and insulating Cs 4 PbBr 6 nanocrystals. We demonstrate that, in this case, the two materials inevitably hybridize, forming nanoparticles with a spherical shape. The actual amount of these Cs 4 PbBr 6 nanocrystals and nanohybrids increases for synthesis at lower temperatures, i.e., the condition typically used for the development of perovskite CsPbBr 3 nanocrystals with smaller sizes. We use state-of-the-art electron energy loss spectroscopy to characterize nanoparticles at the single object level. This method allows distinguishing between optical characteristics of a pure Cs 4 PbBr 6 and CsPbBr 3 nanocrystal and their nanohybrid. In this way, we resolve some of the recent misconceptions concerning possible visible absorption and emission of Cs 4 PbBr 6 . Our method provides detailed structural characterization, and combined with modeling, we conclusively identify the nanospheres as CsPbBr 3 /Cs 4 PbBr 6 hybrids. We show that the two phases are independent of each other's presence and merge symbiotically. Herein, the optical characteristics of the parent materials are preserved, allowing for an increased absorption in the UV due to Cs 4 PbBr 6 , accompanied by the distinctive efficient green emission resulting from CsPbBr 3 .

Properties of Cs-intercalated single wall carbon nanotubes investigated by 133Cs Nuclear Magnetic resonance

KAUST Repository

Schmid, Marc R.

2012-11-01

In the present study, we investigated Cs-intercalated single wall carbon nanotubes (SWCNTs) using 133Cs Nuclear Magnetic resonance. We show that there are two types of Cs cations depending on the insertion level. Indeed, at low concentrations, Static spectra analysis shows that the Cs (α)+ species are fully ionized, i.e. α equal ca.1, while at higher concentrations a second paramagnetically shifted line appears, indicating the formation of Cs (β)+ ions with β < α ∼ +1. At low concentrations and low temperatures the Cs (α)+ ions exhibit a weak hyperfine coupling to the SWCNT conduction electrons, whereas, at higher temperatures, a thermally activated slow-motion diffusion process of the Cs (α)+ ions occurs along the interstitial channels present within the carbon nanotube bundles. At high concentrations, the Cs (β)+ ions seem to occupy well defined positions relative to the carbon lattice. As a matter of fact, the Korringa relaxation behavior suggests a strong hyperfine coupling between Cs nuclei and conduction electrons in the carbon nanotubes and a partial charge transfer, which suggest a plausible Cs(6s)-C(2p) hybridization. © 2012 Elsevier Ltd. All rights reserved.

The effective and environmental half-life of {sup 137}Cs at Coral Islands at the former US nuclear test site

Energy Technology Data Exchange (ETDEWEB)

Robison, William L. E-mail: robison1@llnl.gov; Conrado, Cynthia L.; Bogen, Kenneth T.; Stoker, A. Carol

2003-07-01

The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 ({sup 137}Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of {sup 137}Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of {sup 137}Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of {sup 137}Cs and {sup 90}Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of {sup 137}Cs and {sup 90}Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of {sup 137}Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the {sup 137}Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the {sup 137}Cs/{sup 90}Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the {sup 137}Cs/{sup 90}Sr ratios in soil in 1987 relative to the{sup 137}Cs/{sup 90}Sr ratios at the time of deposition in 1954 is less

Development of Chemical and Metabolite Sensors for Rhodococcus opacus PD630.

Science.gov (United States)

DeLorenzo, Drew M; Henson, William R; Moon, Tae Seok

2017-10-20

Rhodococcus opacus PD630 is a nonmodel, Gram-positive bacterium that possesses desirable traits for biomass conversion, including consumption capabilities for lignocellulose-based sugars and toxic lignin-derived aromatic compounds, significant triacylglycerol accumulation, relatively rapid growth rate, and genetic tractability. However, few genetic elements have been directly characterized in R. opacus, limiting its application for lignocellulose bioconversion. Here, we report the characterization and development of genetic tools for tunable gene expression in R. opacus, including: (1) six fluorescent reporters for quantifying promoter output, (2) three chemically inducible promoters for variable gene expression, and (3) two classes of metabolite sensors derived from native R. opacus promoters that detect nitrogen levels or aromatic compounds. Using these tools, we also provide insights into native aromatic consumption pathways in R. opacus. Overall, this work expands the ability to control and characterize gene expression in R. opacus for future lignocellulose-based fuel and chemical production.

Thermal gravimetric analysis of the CsCuCl3, Cs2CuCl4 and Cs2CuCl4x2H2O crystals

International Nuclear Information System (INIS)

Soboleva, L.V.; Vasil'eva, M.G.

1977-01-01

The thermal characteristics of crystals of Cs 2 CuCl 4 , Cs 2 CuCl 4 x2H 2 O, and CsCuCl 3 were investigated thermogravimetrically. The derivatogram of the Cs 2 CuCl 4 crystal is characterized by the presence of a single endothermal effect at 505 deg C. The derivatogram of the Cs 2 CuCl 4 x2H 2 O crystal contains three endothermal effects: at 40, 135, and 480 deg C. The derivatogram of the CsCuCl 3 crystal shows the presence of two endothermal effects at 142 and 455 deg C. The thermogravimetric data on Cs 2 CuCl 4 and CsCuCl 3 crystals reveal crystal decomposition on melting; hence, these crystals cannot be grown from melts

Purification, characterization of Chondroitinase ABC from Sphingomonas paucimobilis and in vitro cardiocytoprotection of the enzymatically degraded CS-A.

Science.gov (United States)

Fu, Jingyun; Jiang, Zhiwen; Chang, Jing; Han, Baoqin; Liu, Wanshun; Peng, Yanfei

2018-04-24

An extracellular chondroitinase ABC (ChSase ABC) produced by Sphingomonas paucimobilis was purified to homogeneity through ammonium sulfate precipitation, DEAE-Sepharose Fast Flow and Sephadex G-100 chromatography. The molecular weight was 82.3 kDa. It showed specific lyase activity toward chondroitin sulfate A (CS-A), CS-B, CS-C and hyaluronan (HA). Using CS-A as substrate, the specific activity was 98.04 U/mg, the maximal reaction rate (V max ) and Michaelis-Menten constant (K m ) were 0.49 μmol/min/ml and 0.79 mg/ml, respectively. Highest activity was obtained at pH 6.5 and 40 °C, and Hg 2+ could strongly inhibit the enzyme activity. Mass spectrometry analysis indicated CS-A was degraded to unsaturated disaccharides by ChSase ABC. In vitro cytotoxic tests showed that CS-A oligosaccharide at the concentration of 50 and 100 μg/ml could promote the proliferation of normal H9c2 myocardial cells, decrease the damage induced by isoproterenol (ISO) and accelerate the recovery of cells injured by ISO. These findings suggested that ChSase ABC from Sphingomonas paucimobilis could be a promising tool for the structural analysis and bioactive oligosaccharide preparation of glucosaminoglycans. Copyright © 2018 Elsevier B.V. All rights reserved.

135Cs/137Cs isotopic composition of environmental samples across Europe: Environmental transport and source term emission applications

International Nuclear Information System (INIS)

Snow, Mathew S.; Snyder, Darin C.

2016-01-01

135 Cs/ 137 Cs isotopic analyses represent an important tool for studying the fate and transport of radiocesium in the environment; in this work the 135 Cs/ 137 Cs isotopic composition in environmental samples taken from across Europe is reported. Surface soil and vegetation samples from western Russia, Ukraine, Austria, and Hungary show consistent aged thermal fission product 135 Cs/ 137 Cs isotope ratios of 0.58 ± 0.01 (age corrected to 1/1/15), with the exception of one sample of soil-moss from Hungary which shows an elevated 135 Cs/ 137 Cs ratio of 1.78 ± 0.12. With the exception of the outlier sample from Hungary, surface soil/vegetation data are in quantitative agreement with values previously reported for soils within the Chernobyl exclusion zone, suggesting that radiocesium at these locations is primarily composed of homogenous airborne deposition from Chernobyl. Seawater samples taken from the Irish Sea show 135 Cs/ 137 Cs isotope ratios of 1.22 ± 0.11 (age corrected to 1/1/15), suggesting aged thermal fission product Cs discharged from Sellafield. The differences in 135 Cs/ 137 Cs isotope ratios between Sellafield, Chernobyl, and global nuclear weapons testing fallout indicate that 135 Cs/ 137 Cs isotope ratios can be utilized to discriminate between and track radiocesium transport from different nuclear production source terms, including major emission sources in Europe. - Highlights: • 135 Cs/ 137 Cs useful for tracking anthropogenic environmental radiocesium releases. • European surface soils/vegetation have uniform ratio consistent with Chernobyl. • 135 Cs/ 137 Cs in Irish sea represents thermal fission ratio distinct from Chernobyl. • Can distinguish between major source terms in Europe based on 135 Cs/ 137 Cs.

Reactive barriers for 137Cs retention

International Nuclear Information System (INIS)

Krumhansl, James L.; Brady, Patrick V.; Anderson, Howard L.

2000-01-01

137 Cs was dispersed globally by cold war activities and, more recently, by the Chernobyl accident. Engineered extraction of 137 Cs from soils and groundwaters is exceedingly difficult. Because the half life of 137 Cs is only 30.2 years, remediation might be more effective (and less costly) if 137 Cs bioavailability could be demonstrably limited for even a few decades by use of a reactive barrier. Essentially permanent isolation must be demonstrated in those few settings where high nuclear level wastes contaminated the environment with 135 Cs (half life 2.3x10 6 years) in addition to 137 Cs. Clays are potentially a low-cost barrier to Cs movement, though their long-term effectiveness remains untested. To identify optimal clays for Cs retention Cs resorption was measured for five common clays: Wyoming Montmorillonite (SWy-1), Georgia Kaolinites (KGa-1 and KGa-2), Fithian Illite (F-Ill), and K-Metabentonite (K-Mbt). Exchange sites were pre-saturated with 0.16 M CsCl for 14 days and readily exchangeable Cs was removed by a series of LiNO 3 and LiCl washes. Washed clay were then placed into dialysis bags and the Cs release to the deionized water outside the bags measured. Release rates from 75 to 139 days for SWy-1, K-Mbt and F- 111 were similar; 0.017 to 0.021% sorbed Cs released per day. Both kaolinites released Cs more rapidly (0.12 to 0.05% of the sorbed Cs per day). In a second set of experiments, clays were doped for 110 days and subjected to an extreme and prolonged rinsing process. All the clays exhibited some capacity for irreversible Cs uptake so most soils have some limited ability to act as a natural barrier to Cs migration. However, the residual loading was greatest on K-Mbt (∼ 0.33 wt% Cs). Thus, this clay would be the optimal material for constructing artificial reactive barriers

137Cs in man organism

International Nuclear Information System (INIS)

Marej, A.N.; Barkhudarov, R.M.

1980-01-01

Considered are the levels of 137 Cs content in the organism of adult urban population of the USSR and the main regularities of their alterations during 1962-1974. The non-uniform distribution of levels of 137 Cs buildup in adult population is shown to be connected with soil and geographic conditions. Food stuffs of local production have a noticeable effect on the levels of 137 Cs buildup in the organism of urban population. Calculation methods are used to study 137 Cs administration in a human organism. No significant difference is found between the indexes of 137 Cs content in the organism of rural and urban population. Presented are the levels of 137 Cs content in the organisms of inhabitants of such regions as Far North and Byelorussian-Ukrainian woodlands. Given are the reasons for the increased content of 137 Cs in the organism of rural population of these zones

Comparative Genomics of Rhodococcus equi Virulence Plasmids Indicates Host-Driven Evolution of the vap Pathogenicity Island.

Science.gov (United States)

MacArthur, Iain; Anastasi, Elisa; Alvarez, Sonsiray; Scortti, Mariela; Vázquez-Boland, José A

2017-05-01

The conjugative virulence plasmid is a key component of the Rhodococcus equi accessory genome essential for pathogenesis. Three host-associated virulence plasmid types have been identified the equine pVAPA and porcine pVAPB circular variants, and the linear pVAPN found in bovine (ruminant) isolates. We recently characterized the R. equi pangenome (Anastasi E, et al. 2016. Pangenome and phylogenomic analysis of the pathogenic actinobacterium Rhodococcus equi. Genome Biol Evol. 8:3140-3148.) and we report here the comparative analysis of the virulence plasmid genomes. Plasmids within each host-associated type were highly similar despite their diverse origins. Variation was accounted for by scattered single nucleotide polymorphisms and short nucleotide indels, while larger indels-mostly in the plasticity region near the vap pathogencity island (PAI)-defined plasmid genomic subtypes. Only one of the plasmids analyzed, of pVAPN type, was exceptionally divergent due to accumulation of indels in the housekeeping backbone. Each host-associated plasmid type carried a unique PAI differing in vap gene complement, suggesting animal host-specific evolution of the vap multigene family. Complete conservation of the vap PAI was observed within each host-associated plasmid type. Both diversity of host-associated plasmid types and clonality of specific chromosomal-plasmid genomic type combinations were observed within the same R. equi phylogenomic subclade. Our data indicate that the overall strong conservation of the R. equi host-associated virulence plasmids is the combined result of host-driven selection, lateral transfer between strains, and geographical spread due to international livestock exchanges. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Exploring Polaronic, Excitonic Structures and Luminescence in Cs4PbBr6/CsPbBr3.

Science.gov (United States)

Kang, Byungkyun; Biswas, Koushik

2018-02-15

Among the important family of halide perovskites, one particular case of all-inorganic, 0-D Cs 4 PbBr 6 and 3-D CsPbBr 3 -based nanostructures and thin films is witnessing intense activity due to ultrafast luminescence with high quantum yield. To understand their emissive behavior, we use hybrid density functional calculations to first compare the ground-state electronic structure of the two prospective compounds. The dispersive band edges of CsPbBr 3 do not support self-trapped carriers, which agrees with reports of weak exciton binding energy and high photocurrent. The larger gap 0-D material Cs 4 PbBr 6 , however, reveals polaronic and excitonic features. We show that those lattice-coupled carriers are likely responsible for observed ultraviolet emission around ∼375 nm, reported in bulk Cs 4 PbBr 6 and Cs 4 PbBr 6 /CsPbBr 3 composites. Ionization potential calculations and estimates of type-I band alignment support the notion of quantum confinement leading to fast, green emission from CsPbBr 3 nanostructures embedded in Cs 4 PbBr 6 .

Crystallization and crystallographic analysis of the Rhodococcus rhodochrous NCIMB 13064 DhaA mutant DhaA31 and its complex with 1,2,3-trichloropropane

Czech Academy of Sciences Publication Activity Database

Lahoda, M.; Chaloupková, R.; Stsiapanava, A.; Damborský, J.; Kutá-Smatanová, Ivana

2011-01-01

Roč. 67, Part 3 (2011), s. 397-400 ISSN 1744-3091 R&D Projects: GA MŠk(CZ) LC06010; GA MŠk(CZ) ED1.1.00/02.0073 Institutional research plan: CEZ:AV0Z60870520 Keywords : haloalkane dehalogenases * DhaA * Rhodococcus rhodochrous Subject RIV: CE - Biochemistry Impact factor: 0.506, year: 2011

Temperature and Pressure Dependence of the Reaction S plus CS (+M) -> CS2 (+M)

DEFF Research Database (Denmark)

Glarborg, Peter; Marshall, Paul; Troe, Juergen

2015-01-01

Experimental data for the unimolecular decomposition of CS2 from the literature are analyzed by unimolecular rate theory with the goal of obtaining rate constants for the reverse reaction S + CS (+M) -> CS2 (+M) over wide temperature and pressure ranges. The results constitute an important input...

A simple method for the deconvolution of 134 Cs/137 Cs peaks in gamma-ray scintillation spectrometry

International Nuclear Information System (INIS)

Darko, E.O.; Osae, E.K.; Schandorf, C.

1998-01-01

A simple method for the deconvolution of 134 Cs / 137 Cs peaks in a given mixture of 134 Cs and 137 Cs using Nal(TI) gamma-ray scintillation spectrometry is described. In this method the 795 keV energy of 134 Cs is used as a reference peak to calculate the activity of the 137 Cs directly from the measured peaks. Certified reference materials were measured using the method and compared with a high resolution gamma-ray spectrometry measurements. The results showed good agreement with the certified values. The method is very simple and does not need any complicated mathematics and computer programme to de- convolute the overlapping 604.7 keV and 661.6 keV peaks of 134 Cs and 137 Cs respectively. (author). 14 refs.; 1 tab., 2 figs

Tunable CsPbBr3/Cs4PbBr6 phase transformation and their optical spectroscopic properties.

Science.gov (United States)

Chen, Xiao; Chen, Daqin; Li, Junni; Fang, Gaoliang; Sheng, Hongchao; Zhong, Jiasong

2018-04-24

As a novel type of promising materials, metal halide perovskites are a rising star in the field of optoelectronics. On this basis, a new frontier of zero-dimensional perovskite-related Cs4PbBr6 with bright green emission and high stability has attracted an enormous amount of attention, even though its photoluminescence still requires to clarification. Herein, the controllable phase transformation between three-dimensional CsPbBr3 and zero-dimensional Cs4PbBr6 is easily achieved in a facile ligand-assisted supersaturated recrystallization synthesis procedure via tuning the amount of surfactants, and their unique optical properties are investigated and compared in detail. Both Cs4PbBr6 and CsPbBr3 produce remarkably intense green luminescence with quantum yields up to 45% and 80%, respectively; however, significantly different emitting behaviors are observed. The fluorescence lifetime of Cs4PbBr6 is much longer than that of CsPbBr3, and photo-blinking is easily detected in the Cs4PbBr6 product, proving that the zero-dimensional Cs4PbBr6 is indeed a highly luminescent perovskite-related material. Additionally, for the first time, tunable emissions over the visible-light spectral region are demonstrated to be achievable via halogen composition modulations in the Cs4PbX6 (X = Cl, Br, I) samples. Our study brings a simple method for the phase control of CsPbBr3/Cs4PbBr6 and demonstrates the intrinsic luminescence nature of the zero-dimensional perovskite-related Cs4PbX6 products.

Microhydration of caesium compounds: Cs, CsOH, CsI and Cs₂I₂ complexes with one to three H₂O molecules of nuclear safety interest.

Science.gov (United States)

Sudolská, Mária; Cantrel, Laurent; Cernušák, Ivan

2014-04-01

Structure and thermodynamic properties (standard enthalpies of formation and Gibbs free energies) of hydrated caesium species of nuclear safety interest, Cs, CsOH, CsI and its dimer Cs₂I₂, with one up to three water molecules, are calculated to assess their possible existence in severe accident occurring to a pressurized water reactor. The calculations were performed using the coupled cluster theory including single, double and non-iterative triple substitutions (CCSD(T)) in conjunction with the basis sets (ANO-RCC) developed for scalar relativistic calculations. The second-order spin-free Douglas-Kroll-Hess Hamiltonian was used to account for the scalar relativistic effects. Thermodynamic properties obtained by these correlated ab initio calculations (entropies and thermal capacities at constant pressure as a function of temperature) are used in nuclear accident simulations using ASTEC/SOPHAEROS software. Interaction energies, standard enthalpies and Gibbs free energies of successive water molecules addition determine the ordering of the complexes. CsOH forms the most hydrated stable complexes followed by CsI, Cs₂I₂, and Cs. CsOH still exists in steam atmosphere even at quite high temperature, up to around 1100 K.

1+ collective states of 124Cs and 126Cs nuclei

International Nuclear Information System (INIS)

Ivanova, S.P.; Kuliev, A.A.; Salamov, D.I.

1977-01-01

Within the framework of the random phase approximation β-decay properties of the 1 + states of 124 Cs and 126 Cs have been investigated. Greatly collectivized 1 + states in odd-odd nuclei are produced by the spin-dependent charge-exchange nucleon interaction. For numerical calculations the scheme of single-particle levels in the deformed Saxon-Woods potential has been used

Distribuição de 137Cs em três solos representativos do estado de pernambuco Distribution of 137Cs in three representative soils of pernambuco state, Brazil

Directory of Open Access Journals (Sweden)

Patrik Diogo Antunes

2010-06-01

Full Text Available O 137Cs tem sido usado para quantificar perdas ou deposição de solo, com base em valores das concentrações em áreas de referência que tiveram pouca perturbação nas últimas décadas. Determinações em áreas assim ainda não foram feitas na região Nordeste do Brasil. Em Pernambuco, foram selecionadas três áreas com topografia plana, vegetação nativa e solos não perturbados, em Goiana, Sertânia e Araripina. Em cada área, foram marcados quatro pontos, distantes 20 a 50 m um do outro, e em cada um retiradas amostras de solo, em camadas consecutivas de 3 cm de espessura, até 30 cm. As atividades de 137Cs foram determinadas usando espectrometria gama com detector de germânio hiperpuro (HPGe. Os estoques médios de 137Cs (Bq m-2 foram de 71,6 ± 6,3 em Goiana, 64,0 ± 13,8 em Araripina e 95,5 ± 9,8 em Sertânia. Valores nessa faixa têm sido relatados na Paraíba e na Bahia e, mais altos, na região Sudeste, confirmando a diminuição dos estoques em áreas mais próximas do Equador. As maiores atividades ocorreram nas camadas superficiais, variando de 0,5 a 1,6 Bq kg-1, e decresceram linearmente com a profundidade, até os limites de detecção: 18 cm em Araripina, 15 cm em Goiana e 9 cm em Sertânia. Em Goiana, acima dos horizontes inorgânicos havia um horizonte orgânico, com a mais alta atividade (2,06 Bq kg-1. Atividades e estoque altos e menor aprofundamento em Sertânia poderiam ser explicados pela predominância de argilominerais 2:1, em contraposição à de argilominerais 1:1 nos outros locais. Houve correlações positivas entre a atividade de 137Cs e os valores de pH em água e KCl e correlação negativa com as concentrações de Al3+. Confirma-se que, em áreas de referência, a maior atividade do 137Cs está na camada superior, com decréscimos regulares ao longo do perfil do solo.Contents of 137Cs have been used to quantify soil loss or accumulations, based on values of reference sites with little soil disturbance

Cesium platinide hydride 4Cs{sub 2}Pt.CsH: an intermetallic double salt featuring metal anions

Energy Technology Data Exchange (ETDEWEB)

Smetana, Volodymyr [Ames Laboratory, US Department of Energy, and Critical Materials Institute, Ames, Iowa, 50011-3020 (United States); Mudring, Anja-Verena [Ames Laboratory, US Department of Energy, and Critical Materials Institute, Ames, Iowa, 50011-3020 (United States); Department of Materials Sciences and Engineering, Iowa State University, Ames, Iowa, 50011-3111 (United States)

2016-11-14

With Cs{sub 9}Pt{sub 4}H a new representative of ionic compounds featuring metal anions can be added to this rare-membered family. Cs{sub 9}Pt{sub 4}H exhibits a complex crystal structure containing Cs{sup +} cations, Pt{sup 2-} and H{sup -} anions. Being a red, transparent compound its band gap is in the visible range of the electromagnetic spectrum and the ionic type of bonding is confirmed by quantum chemical calculations. This cesium platinide hydride can formally be considered as a double salt of the ''alloy'' cesium-platinum, or better cesium platinide, Cs{sub 2}Pt, and the salt cesium hydride CsH according to Cs{sub 9}Pt{sub 4}H≡4 Cs{sub 2}Pt.CsH. (copyright 2016 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

Isolation and characterization of styrene metabolism genes from styrene-assimilating soil bacteria Rhodococcus sp. ST-5 and ST-10.

Science.gov (United States)

Toda, Hiroshi; Itoh, Nobuya

2012-01-01

Styrene metabolism genes were isolated from styrene-assimilating bacteria Rhodococcus sp. ST-5 and ST-10. Strain ST-5 had a gene cluster containing four open reading frames which encoded styrene degradation enzymes. The genes showed high similarity to styABCD of Pseudomonas sp. Y2. On the other hand, strain ST-10 had only two genes which encoded styrene monooxygenase and flavin oxidoreductase (styAB). Escherichia coli transformants possessing the sty genes of strains ST-5 and ST-10 produced (S)-styrene oxide from styrene, indicating that these genes function as styrene degradation enzymes. Metabolite analysis by resting-cell reaction with gas chromatography-mass spectrometry revealed that strain ST-5 converts styrene to phenylacetaldehyde via styrene oxide by styrene oxide isomerase (styC) reaction. On the other hand, strain ST-10 lacked this enzyme, and thus accumulated styrene oxide as an intermediate. HPLC analysis showed that styrene oxide was spontaneously isomerized to phenylacetaldehyde by chemical reaction. The produced phenylacetaldehyde was converted to phenylacetic acid (PAA) in strain ST-10 as well as in strain ST-5. Furthermore, phenylacetic acid was converted to phenylacetyl-CoA by the catalysis of phenylacetate-CoA ligase in strains ST-5 and ST-10. This study proposes possible styrene metabolism pathways in Rhodococcus sp. strains ST-5 and ST-10. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Knudsen cell--mass spectrometer studies of cesium--urania interactions. [Cs/sub 2/CO/sub 3/ or CsOH

Energy Technology Data Exchange (ETDEWEB)

Collins, J.L.; Osborne, M.F.; Malinauskas, A.P.; Lorenz, R.A.; Manning, S.R.

1976-06-01

Limited Knudsen cell--mass spectrometer studies were made of the partial pressures of cesium-containing species (assumed to be primarily Cs(g)) over Cs/sub 2/CO/sub 3/ and over phase equilibria involving UO/sub 2/ and probable Cs-U-O compounds formed from mixtures that initially contained either Cs/sub 2/CO/sub 3/-UO/sub 2/ or CsOH-UO/sub 2/. Although additional work is required to further define the equilibria involved, the data demonstrate unambiguously a significant reduction in cesium partial pressures due to probable Cs-U-O compound formation and indicate essentially identical behavior with either CsOH or Cs/sub 2/CO/sub 3/ as the starting material with UO/sub 2/.

Development of certified matrix reference materials for quality assurance of screening 134Cs and 137Cs in food

International Nuclear Information System (INIS)

Ishizu, H.; Yamada, T.

2013-01-01

A certified reference material using activated alumina powder certified for activity of 134 Cs and 137 Cs was developed. The results of the verification and the certification are described. The certified reference material can be used for quality assurance of screening activity measurements of 134 Cs and 137 Cs in food/foodstuffs. Commercially available equipments were experimentally tested using the CRM and another CRM including 40 K. The results of these tests are also shown. - Highlights: • CRM of 134 Cs and 137 Cs using activated alumina was developed. • CRM including 134 Cs, 137 Cs and 40 K was also developed. • Results of experimental performance test of commercial inspection equipments using CRMs were shown

Ab Initio investigation of cesium monoxide of CsO and CsO+

International Nuclear Information System (INIS)

Zialenina, M.; Kelloe, V.; Cernusak, I.

2015-01-01

Cesium is material with a low work function and, accordingly, atomic Cs has a low value of ionization energy. Therefore cesium is regarded as a good source material for electrons in plasma heating module. One of plasma heating technologies using Cs grid is foreseen as a candidate for the tokamak within the framework of project ITER. Among the possible impurities that can coexist in this module are CsO or CsO + , due to presence of oxygen traces in the heating chamber. We conducted CCSD(T) energy calculations of the cesium oxide (X 2 Σ + ) and its cation (X 3 Σ - ). Here are presented the bond lengths and spectroscopic parameters of both species and ionization energy (IE). Our IE (6.88 eV) is in good agreement with previous theoretical results, experiment indicates substantially lower value (6.22 eV). (authors)

Luminescence properties of undoped CsCaCl3 and CsSrCl3 crystalline scintillators

International Nuclear Information System (INIS)

Fujimoto, Yutaka; Saeki, Keiichiro; Koshimizu, Masanori; Asai, Keisuke; Yanagida, Takayuki

2015-01-01

Intrinsic luminescence properties of undoped CsCaCl 3 and CsSrCl 3 crystalline scintillators were studied. The crystal samples were grown by a vertical Bridgman method. Photoluminescence spectra of the crystals showed Auger-free luminescence (AFL) at 310 nm and self-trapped emission (STE) at 400 nm for CsCaCl 3 and 465 nm for CsSrCl 3 , when vacuum ultraviolet (VUV) light at 84 nm and 160 nm excited the crystals. X-ray excited radioluminescence spectra of the crystals showed some emission bands in the 280-600 nm wavelength range, which are owing to AFL, STE, and other origins such as lattice defects and impurities. Scintillation light yield was 400-300 ph/MeV, and the principal scintillation decay time about 2.5 ns and 12 ns for CsCaCl 3 and 1.8 ns and 13 ns for CsSrCl 3 . (author)

Aerobic degradation of 4-nitroaniline (4-NA) via novel degradation intermediates by Rhodococcus sp. strain FK48

Energy Technology Data Exchange (ETDEWEB)

Khan, Fazlurrahman; Pandey, Janmejay; Vikram, Surendra; Pal, Deepika; Cameotra, Swaranjit Singh, E-mail: ssc@imtech.res.in

2013-06-15

Highlights: • This study reports isolation of a novel bacterium capable of mineralizing 4-nitroaniline (4-NA). • This bacterium has been identified as Rhodococcus sp. strain FK48. • Strain FK48 degrades 4-NA via a novel aerobic degradation pathway that involves 4-AP and 1,2,4-BT. • Subsequent degradation proceeds via ring fission and formation of maleylacetate. • This is the first report showing elucidation of catabolic pathway for microbial degradation 4-NA. -- Abstract: An aerobic strain, Rhodococcus sp. strain FK48, capable of growing on 4-nitroaniline (4-NA) as the sole source of carbon, nitrogen, and energy has been isolated from enrichment cultures originating from contaminated soil samples. During growth studies with non- induced cells of FK48 catalyzed sequential denitrification (release of NO{sub 2} substituent) and deamination (release of NH{sub 2} substituent) of 4-NA. However, none of the degradation intermediates could be identified with growth studies. During resting cell studies, 4-NA-induced cells of strain FK48 transformed 4-NA via a previously unknown pathway which involved oxidative hydroxylation leading to formation of 4-aminophenol (4-AP). Subsequent degradation involved oxidated deamination of 4-AP and formation of 1,2,4-benzenetriol (BT) as the major identified terminal aromatic intermediate. Identification of these intermediates was ascertained by HPLC, and GC–MS analyses of the culture supernatants. 4-NA-induced cells of strain FK48 showed positive activity for 1,2,4-benzenetriol dioxygenase in spectrophotometric assay. This is the first conclusive study on aerobic microbial degradation of 4-NA and elucidation of corresponding metabolic pathway.

Aerobic degradation of 4-nitroaniline (4-NA) via novel degradation intermediates by Rhodococcus sp. strain FK48

International Nuclear Information System (INIS)

Khan, Fazlurrahman; Pandey, Janmejay; Vikram, Surendra; Pal, Deepika; Cameotra, Swaranjit Singh

2013-01-01

Highlights: • This study reports isolation of a novel bacterium capable of mineralizing 4-nitroaniline (4-NA). • This bacterium has been identified as Rhodococcus sp. strain FK48. • Strain FK48 degrades 4-NA via a novel aerobic degradation pathway that involves 4-AP and 1,2,4-BT. • Subsequent degradation proceeds via ring fission and formation of maleylacetate. • This is the first report showing elucidation of catabolic pathway for microbial degradation 4-NA. -- Abstract: An aerobic strain, Rhodococcus sp. strain FK48, capable of growing on 4-nitroaniline (4-NA) as the sole source of carbon, nitrogen, and energy has been isolated from enrichment cultures originating from contaminated soil samples. During growth studies with non- induced cells of FK48 catalyzed sequential denitrification (release of NO 2 substituent) and deamination (release of NH 2 substituent) of 4-NA. However, none of the degradation intermediates could be identified with growth studies. During resting cell studies, 4-NA-induced cells of strain FK48 transformed 4-NA via a previously unknown pathway which involved oxidative hydroxylation leading to formation of 4-aminophenol (4-AP). Subsequent degradation involved oxidated deamination of 4-AP and formation of 1,2,4-benzenetriol (BT) as the major identified terminal aromatic intermediate. Identification of these intermediates was ascertained by HPLC, and GC–MS analyses of the culture supernatants. 4-NA-induced cells of strain FK48 showed positive activity for 1,2,4-benzenetriol dioxygenase in spectrophotometric assay. This is the first conclusive study on aerobic microbial degradation of 4-NA and elucidation of corresponding metabolic pathway

Fast CsI-phoswich detector

International Nuclear Information System (INIS)

Langenbrunner, J.R.

1996-01-01

An improved phoswich radiation detector used pure CsI crystal and a fast plastic scintillator and a single photomultiplier tube. The plastic is arranged to receive incident radiation, and that which passed through then strikes the CsI crystal. Scintillation light from both the plastic and CsI crystal are applied to the photomultiplier tube, with the light from the plastic passing through the crystal without absorption therein. Electronics are provided for analyzing the output of the photomultiplier tube to discriminate responses due to the plastic and the CsI crystal, through short gate and long gate integration, to produce results which are indicative of the characteristics of the different types of incident radiation, even in the presence of large amounts of radiation. The phoswich detector has excellent timing resolution. The scintillators of the CsI- phoswich were chosen for their fast risetimes, of about 3 ns for NE102A, and 30 ns for the pure CsI. 5 figs

Rapid determination of {sup 135}Cs and precise {sup 135}Cs/{sup 137}Cs atomic ratio in environmental samples by single-column chromatography coupled to triple-quadrupole inductively coupled plasma-mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Yang, Guosheng [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan); Division of Nuclear Technology and Applications, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Beijing Engineering Research Center of Radiographic Techniques and Equipment, Beijing 100049 (China); Tazoe, Hirofumi [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan); Yamada, Masatoshi, E-mail: myamada@hirosaki-u.ac.jp [Department of Radiation Chemistry, Institute of Radiation Emergency Medicine, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan)

2016-02-18

For source identification, measurement of {sup 135}Cs/{sup 137}Cs atomic ratio not only provides information apart from the detection of {sup 134}Cs and {sup 137}Cs, but it can also overcome the application limit that measurement of the {sup 134}Cs/{sup 137}Cs ratio has due to the short half-life of {sup 134}Cs (2.06 y). With the recent advancement of ICP-MS, it is necessary to improve the corresponding separation method for rapid and precise {sup 135}Cs/{sup 137}Cs atomic ratio analysis. A novel separation and purification technique was developed for the new generation of triple-quadrupole inductively coupled plasma-mass spectrometry (ICP-MS/MS). The simple chemical separation, incorporating ammonium molybdophosphate selective adsorption of Cs and subsequent single cation-exchange chromatography, removes the majority of isobaric and polyatomic interference elements. Subsequently, the ICP-MS/MS removes residual interference elements and eliminates the peak tailing effect of stable {sup 133}Cs, at m/z 134, 135, and 137. The developed analytical method was successfully applied to measure {sup 135}Cs/{sup 137}Cs atomic ratios and {sup 135}Cs activities in environmental samples (soil and sediment) for radiocesium source identification. - Highlights: • A simple {sup 135}Cs/{sup 137}Cs analytical method was developed. • The separation procedure was based on AMP adsorption and one column chromatography. • {sup 135}Cs/{sup 137}Cs was measured by ICP-MS/MS. • Decontamination factors for Ba, Mo, Sb, and Sn were improved. • {sup 135}Cs/{sup 137}Cs atomic ratios of 0.341–0.351 were found in Japanese soil samples.

A novel vanadosilicate with hexadeca-coordinated Cs{sup +} ions as a highly effective Cs{sup +} remover

Energy Technology Data Exchange (ETDEWEB)

Datta, Shuvo Jit; Moon, Won Kyung; Choi, Do Young; Hwang, In Chul; Yoon, Kyung Byung [Sogang Univ., Seoul (Korea, Republic of). Korea Center for Artificial Photosynthesis

2014-07-07

The effective removal of {sup 137}Cs{sup +} ions from contaminated groundwater and seawater and from radioactive nuclear waste solutions is crucial for public health and for the continuous operation of nuclear power plants. Various {sup 137}Cs{sup +} removers have been developed, but more effective {sup 137}Cs{sup +} removers are still needed. A novel microporous vanadosilicate with mixed-valence vanadium (V{sup 4+} and V{sup 5+}) ions is now reported, which shows an excellent ability for Cs{sup +} capture and immobilization from groundwater, seawater, and nuclear waste solutions. This material is superior to other known materials in terms of selectivity, capacity, and kinetics, and at very low Cs{sup +} concentrations, it was found to be the most effective material for the removal of radioactive Cs{sup +} ions under the test conditions. This novel vanadosilicate also contains hexadeca-coordinated Cs{sup +} ions, which corresponds to the highest coordination number ever described.

The behavior of radioactive 137Cs and stable Cs at the isolated undisturbed mountain pond in Fukui, Japan

International Nuclear Information System (INIS)

Iwamoto, Kazumi; Kimura, Makio; Ando, Kenji; Amano, Hikaru

2003-01-01

The behavior of radioactive 137 Cs and stable Cs at the isolated undisturbed mountain pond in Fukui, Japan was studied for the pond water, the sedimentary grains and the soil near the pond. The concentrations of 137 Cs and stable Cs in the pond water ranged from 0.23 to 0.85 Bq/m 3 and from 0.005 to 0.018 mg/m 3 , respectively. The sedimentary grains were sorted by sieving into fractions with diameter from 2 mm to less than 38 μm. The concentrations of 137 Cs and stable Cs in the sorted grains were measured, and those of the adsorbed state were determined by subtracting the concentration of the grain matrix. The adsorbed concentrations increased with decrease in particle diameter and depended less on the kind of samples. The in-situ distribution coefficient Kd depended largely on particle diameter and increased with the decrease in diameter. The values of Kd ranged from about 20 to 1200 m 3 /kg for stable Cs and about 15 to 1000 m 3 /kg for 137 Cs, and the Kd of 137 Cs seemed to be slightly smaller than that of stable Cs. The concentration of stable Cs in the sedimentary mud was found to be close to that of the fine grains. The concentrations of stable Cs in the soil near the pond was about 7.7 mg/kg, and that of 137 Cs was about 0.6 kBq/kg for the surface layer soil and decreased with increase in soil depth. (author)

The Godparent Plan: A Pedagogical Strategy for CS1 Accompaniment and CS2 Pedagogical Enhancement

Directory of Open Access Journals (Sweden)

Pedro Guillermo Feijóo-García

2018-02-01

Full Text Available Courses such as CS1 and CS2 can present an interesting pedagogical challenge when it comes to the theory-practice relationship, along with aspects that involve the course's logistics, the programming language used, and the characteristics of the students involved in the process. This study presents an innovative didactic approach, oriented towards the accompaniment of CS1 students by CS2 students at Universidad El Bosque, Colombia, seeking with this Godparent Plan, to provide a personalized accompaniment to first semester students, whereby CS2 students enhance their domain over concepts and skills while accompanying, explaining and teaching younger peers. The results of this study are favorable, outlining a didactic scheme that can be adapted and replicated in other curricular scenarios.

Characterization of the expression of the thcB gene, coding for a pesticide-degrading cytochrome P-450 in Rhodococcus strains.

OpenAIRE

Shao, Z Q; Behki, R

1996-01-01

A cytochrome P-450 system in Rhodococcus strains, encoded by thcB, thcC, and thcD, participates in the degradation of thiocarbamates and several other pesticides. The regulation of the system was investigated by fusing a truncated lacZ in frame to thcB, the structural gene for the cytochrome P-450 monooxygenase. Analysis of the thcB-lacZ fusion showed that the expression of thcB was 10-fold higher in the presence of the herbicide EPTC (s-ethyl dipropylthiocarbamate). Similar enhancement of th...

Correlations between potassium, rubidium and cesium (133Cs and 137Cs) in sporocarps of Suillus variegatus in a Swedish boreal forest

International Nuclear Information System (INIS)

Vinichuk, M.; Rosen, K.; Johanson, K.J.; Dahlberg, A.

2011-01-01

An analysis of sporocarps of ectomycorrhizal fungi Suillus variegatus assessed whether cesium ( 133 Cs and 137 Cs) uptake was correlated with potassium (K) or rubidium (Rb) uptake. The question was whether intraspecific correlations of Rb, K and 133 Cs mass concentrations with 137 Cs activity concentrations in sporocarps were higher within, rather than among, different fungal species, and if genotypic origin of sporocarps within a population affected uptake and correlation. Sporocarps (n = 51) from a Swedish forest population affected by the fallout after the Chernobyl accident were studied. The concentrations were 31.9 ± 6.79 g kg -1 for K (mean ± SD, dwt), 0.40 ± 0.09 g kg -1 for Rb, 8.7 ± 4.36 mg kg -1 for 133 Cs and 63.7 ± 24.2 kBq kg -1 for 137 Cs. The mass concentrations of 133 Cs correlated with 137 Cs activity concentrations (r = 0.61). There was correlation between both 133 Cs concentrations (r = 0.75) and 137 Cs activity concentrations (r = 0.44) and Rb, but the 137 Cs/ 133 Cs isotopic ratio negatively correlated with Rb concentration. Concentrations of K and Rb were weakly correlated (r = 0.51). The 133 Cs mass concentrations, 137 Cs activity concentrations and 137 Cs/ 133 Cs isotopic ratios did not correlate with K concentrations. No differences between, within or, among genotypes in S. variegatus were found. This suggested the relationships between K, Rb, 133 Cs and 137 Cs in sporocarps of S. variegatus is similar to other fungal species. - Highlights: → We studied uptake of Cs ( 133 Cs and 137 Cs), K and Rb by Suillus variegates sporocarps. → Genotypic origin of fungus did not affect uptake of studied elements (isotopes). → Genotypic origin did not affect correlation between Cs ( 133 Cs and 137 Cs), K and Rb.

Measurement of thermal neutron cross section and resonance integral of the reaction {sup 135}Cs(n,{gamma}){sup 136}Cs

Energy Technology Data Exchange (ETDEWEB)

Katoh, Toshio; Nakamura, Shoji; Harada, Hideo [Power Reactor and Nuclear Fuel Development Corp., Tokyo (Japan); Hatsukawa, Yuichi; Shinohara, Nobuo; Hata, Kentaro; Kobayashi, Katsutoshi; Motoishi, Shoji; Tanase, Masakazu

1997-03-01

The thermal neutron(2,200 m/s neutron) capture cross section({sigma}{sub 0}) and the resonance integral(I{sub 0}) of the reaction {sup 135}Cs(n,{gamma}){sup 136}Cs were measured by an activation method. Targets of radioactive cesium, which include {sup 135}Cs, {sup 137}Cs and stable {sup 133}Cs, were irradiated with reactor neutrons within or without a Cd shield case. The ratio of the number of nuclei of {sup 135}Cs to that of {sup 137}Cs was measured with a quadrupole mass spectrometer. This ratio and the ratio of activity of {sup 136}Cs to that of {sup 137}Cs were used for deduction of the {sigma}{sub 0} and the I{sub 0} of {sup 135}Cs. The {sigma}{sub 0} and the I{sub 0} of the reaction {sup 135}Cs(n,{sigma}){sup 136}Cs were 8.3 {+-} 0.3 barn and 38.1 {+-} 2.6 barn, respectively. (author)

Cs/CsPbX3 (X = Br, Cl) epitaxial heteronanocrystals with magic-angle stable/metastable grain boundary

Science.gov (United States)

Zhang, Yumeng; Fan, Baolu; Wu, Wenhui; Fan, Jiyang

2017-05-01

Metal-semiconductor heteronanostructures are crucial building blocks of nanoscale electronic and optoelectronic devices. However, the lattice misfit remains a challenge in constructing heteronanostructures. Perovskite nanocrystals are superior candidates for constructing nanodevices owing to excellent optical, ferroelectric, and superconducting properties. We report the epitaxial growth of lattice-matched Cs/CsPbBr3 metal-semiconductor heteronanocrystals in a liquid medium. The well-crystallized ultrathin Cs layers grow epitaxially on the surfaces of colloidal CsPbBr3 nanocrystals, forming heteronanocrystals with interface diameters of several nanometers. Most of them are pseudomorphic with coherent interfaces free from dislocations, and the others exhibit discrete high-angle grain boundaries. The model based on the calculation of the elastic potential energy of the epilayer and analysis of the near-coincidence sites explains well the experimental result. The analysis shows that the excellent lattice match between the metal and the semiconductor ensures the ideal epitaxial-growth of both Cs/CsPbBr3 and Cs/CsPbCl3 heteronanocrystals. Such metal/semiconductor heteronanocrystals pave the way for developing perovskite-based nanodevices.

Phase Transitions in CsSnCl3 and CsPbBr3 An NMR and NQR Study

Science.gov (United States)

Sharma, Surendra; Weiden, Norbert; Weiss, Alarich

1991-04-01

The phase transitions in CsSnCl3 and CsPbBr3 have been studied by X-ray powder diffraction, by 81Br-NQR and by 'H-, 119Sn-, and 113Cs-NMR. At room temperature in air CsSnCl3 forms a hydrate which can be dehydrated to the monoclinic phase II of CsSnCl3. The high temperature phase I has the Perovskite structure, as the X-ray and NMR experiments show. The three phases of CsPbBr3, known from literature, have been corroborated. The results are discussed in the framework of the group ABX3, A = alkalimetal ion, B = IV main group ion, and X = Halogen ion

A preliminary study on 226Ra, 232Th, 40K and 137Cs activity concentrations in vegetables and fruits frequently consumed by inhabitants of Elazig Region, Turkey

International Nuclear Information System (INIS)

Cumhur Canbazoglu; Mahmut Dogru

2013-01-01

Determining radioactivity levels in foodstuffs is of great importance for the protection of human health. In addition, the literature includes few studies related to this subject in Turkey. In this study, gamma spectroscopic system was used in order to measure 226 Ra, 232 Th, 40 K and 137 Cs activity concentrations in vegetables and fruits produced in Elazig( Region. The average activity concentrations in vegetables was calculated as 0.64 ± 0.26 Bq kg -1 for 226 Ra, 0.65 ± 0.14 Bq kg -1 for 232 Th, 13.98 ± 1.22 Bq kg -1 for 40 K, and 0.54 ± 0.04 Bq kg -1 for 137 Cs. The average activity concentrations in fruits were 1.52 ± 0.34, 0.98 ± 0.23, 18.66 ± 1.13 and 0.59 ± 0.16 Bq kg -1 , respectively for 226 Ra, 232 Th, 40 K and 137 Cs. Total committed effective dose value was determined as 20 and 30.55 μSv y -1 , respectively for vegetables and fruits. The findings were compared with previous data reported for Turkey and other regions of the world. (author)

VERA-CS Verification & Validation Plan

Energy Technology Data Exchange (ETDEWEB)

Downar, Thomas [Univ. of Michigan, Ann Arbor, MI (United States)

2017-02-01

This report summarizes the current status of VERA-CS Verification and Validation for PWR Core Follow operation and proposes a multi-phase plan for continuing VERA-CS V&V in FY17 and FY18. The proposed plan recognizes the hierarchical nature of a multi-physics code system such as VERA-CS and the importance of first achieving an acceptable level of V&V on each of the single physics codes before focusing on the V&V of the coupled physics solution. The report summarizes the V&V of each of the single physics codes systems currently used for core follow analysis (ie MPACT, CTF, Multigroup Cross Section Generation, and BISON / Fuel Temperature Tables) and proposes specific actions to achieve a uniformly acceptable level of V&V in FY17. The report also recognizes the ongoing development of other codes important for PWR Core Follow (e.g. TIAMAT, MAMBA3D) and proposes Phase II (FY18) VERA-CS V&V activities in which those codes will also reach an acceptable level of V&V. The report then summarizes the current status of VERA-CS multi-physics V&V for PWR Core Follow and the ongoing PWR Core Follow V&V activities for FY17. An automated procedure and output data format is proposed for standardizing the output for core follow calculations and automatically generating tables and figures for the VERA-CS Latex file. A set of acceptance metrics is also proposed for the evaluation and assessment of core follow results that would be used within the script to automatically flag any results which require further analysis or more detailed explanation prior to being added to the VERA-CS validation base. After the Automation Scripts have been completed and tested using BEAVRS, the VERA-CS plan proposes the Watts Bar cycle depletion cases should be performed with the new cross section library and be included in the first draft of the new VERA-CS manual for release at the end of PoR15. Also, within the constraints imposed by the proprietary nature of plant data, as many as possible of the FY17

Epiphytic fruticose lichens as biomonitors for retrospective evaluation of the 134Cs/137Cs ratio in Fukushima fallout

International Nuclear Information System (INIS)

Ramzaev, V.; Barkovsky, A.; Gromov, A.; Ivanov, S.; Kaduka, M.

2014-01-01

In 2011–2013, sampling of epiphytic fruticose lichens of the genera Usnea, Bryoria and Alectoria was carried out on Sakhalin and Kuril Islands (the Sakhalin region, Russia) to investigate contamination of these organisms with the Fukushima-derived 134 Cs and 137 Cs. Activities of the radionuclides were determined in all 56 samples of lichens taken for the analysis. After correction for radioactive decay (on 15 March 2011), the activity concentrations ranged from 2.1 Bq kg −1 (d.w.) to 52 Bq kg −1 for 134 Cs and from 2.3 Bq kg −1 to 52 Bq kg −1 for 137 Cs. Cesium-134 and 137 Cs activities for the whole set of lichens (n = 56) were strongly positively correlated; Spearman's rank correlation coefficient was calculated as 0.991 (P < 0.01). The activity concentrations of 134 Cs and 137 Cs in Usnea lichens from the Sakhalin and Kunashir islands declined with a factor of three in the period from 2011 to 2013. The average biological half-time for both cesium radionuclides in lichens of the genus Usnea is estimated as 1.3 y. The mean of 0.99 ± 0.10 and median of 0.99 were calculated for the decay corrected 134 Cs/ 137 Cs activities ratios in the lichens (n = 56). The radionuclides ratio in the lichens did not depend on location of sampling site, species and the time that had passed after the Fukushima accident. The regression analysis has shown the background pre-Fukushima level of 137 Cs of 0.4 ± 0.3 Bq kg −1 , whereas the ratio between the Fukushima-borne 134 Cs and 137 Cs in the lichens was estimated as 1.04. The 134 Cs/ 137 Cs activities ratio in lichens from the Sakhalin region is consistent with the ratios reported by others for the heavy contaminated areas on Honshu Island in Japan following the Fukushima accident. The activity concentrations of natural 7 Be in lichens from the Sakhalin region varied between 100 Bq kg −1 and 600 Bq kg −1 ; the activity concentrations did not exhibit temporal variations during a 2y-period of observations. The

Multiplicity of 3-Ketosteroid-9 alpha-Hydroxylase Enzymes in Rhodococcus rhodochrous DSM43269 for Specific Degradation of Different Classes of Steroids

OpenAIRE

Petrusma, Mirjan; Hessels, Gerda; Dijkhuizen, Lubbert; van der Geize, Robert

2011-01-01

The well-known large catabolic potential of rhodococci is greatly facilitated by an impressive gene multiplicity. This study reports on the multiplicity of kshA, encoding the oxygenase component of 3-ketosteroid 9 alpha-hydroxylase, a key enzyme in steroid catabolism. Five kshA homologues (kshA1 to kshA5) were previously identified in Rhodococcus rhodochrous DSM43269. These KshA(DSM43269) homologues are distributed over several phylogenetic groups. The involvement of these KshA homologues in ...

All-Ambient Processed Binary CsPbBr3-CsPb2Br5 Perovskites with Synergistic Enhancement for High-Efficiency Cs-Pb-Br-Based Solar Cells.

Science.gov (United States)

Zhang, Xisheng; Jin, Zhiwen; Zhang, Jingru; Bai, Dongliang; Bian, Hui; Wang, Kang; Sun, Jie; Wang, Qian; Liu, Shengzhong Frank

2018-02-28

All-inorganic CsPbBr 3 perovskite solar cells display outstanding stability toward moisture, light soaking, and thermal stressing, demonstrating great potential in tandem solar cells and toward commercialization. Unfortunately, it is still challenging to prepare high-performance CsPbBr 3 films at moderate temperatures. Herein, a uniform, compact CsPbBr 3 film was fabricated using its quantum dot (QD)-based ink precursor. The film was then treated using thiocyanate ethyl acetate (EA) solution in all-ambient conditions to produce a superior CsPbBr 3 -CsPb 2 Br 5 composite film with a larger grain size and minimal defects. The achievement was attributed to the surface dissolution and recrystallization of the existing SCN - and EA. More specifically, the SCN - ions were first absorbed on the Pb atoms, leading to the dissolution and stripping of Cs + and Br - ions from the CsPbBr 3 QDs. On the other hand, the EA solution enhances the diffusion dynamics of surface atoms and the surfactant species. It is found that a small amount of CsPb 2 Br 5 in the composite film gives the best surface passivation, while the Br-rich surface decreases Br vacancies (V Br ) for a prolonged carrier lifetime. As a result, the fabricated device gives a higher solar cell efficiency of 6.81% with an outstanding long-term stability.

The distribution of 137Cs, K, Rb and Cs in plants in a Sphagnum-dominated peatland in eastern central Sweden

International Nuclear Information System (INIS)

Vinichuk, M.; Johanson, K.J.; Rydin, H.; Rosen, K.

2010-01-01

We record the distribution of 137 Cs, K, Rb and Cs within individual Sphagnum plants (down to 20 cm depth) as well as 137 Cs in vascular plants growing on a peatland in eastern central Sweden. In Calluna vulgaris 137 Cs was mainly located within the green parts, whereas Andromeda polifolia, Eriophorum vaginatum and Vaccinium oxycoccos showed higher 137 Cs activity in roots. Carex rostrata and Menyanthes trifoliata showed variable distribution of 137 Cs within the plants. The patterns of 137 Cs activity concentration distribution as well as K, Rb and Cs concentrations within individual Sphagnum plants were rather similar and were usually highest in the capitula and/or in the subapical segments and lowest in the lower dead segments, which suggests continuous relocation of those elements to the actively growing apical part. The 137 Cs and K showed relatively weak correlations, especially in capitula and living green segments (0-10 cm) of the plant (r = 0.50). The strongest correlations were revealed between 137 Cs and Rb (r = 0.89), and between 137 Cs and stable Cs (r = 0.84). This suggests similarities between 137 Cs and Rb in uptake and relocation within the Sphagnum, but that 137 Cs differs from K.

The distribution of (137)Cs, K, Rb and Cs in plants in a Sphagnum-dominated peatland in eastern central Sweden.

Science.gov (United States)

Vinichuk, M; Johanson, K J; Rydin, H; Rosén, K

2010-02-01

We record the distribution of (137)Cs, K, Rb and Cs within individual Sphagnum plants (down to 20cm depth) as well as (137)Cs in vascular plants growing on a peatland in eastern central Sweden. In Calluna vulgaris(137)Cs was mainly located within the green parts, whereas Andromeda polifolia, Eriophorum vaginatum and Vaccinium oxycoccos showed higher (137)Cs activity in roots. Carex rostrata and Menyanthes trifoliata showed variable distribution of (137)Cs within the plants. The patterns of (137)Cs activity concentration distribution as well as K, Rb and Cs concentrations within individual Sphagnum plants were rather similar and were usually highest in the capitula and/or in the subapical segments and lowest in the lower dead segments, which suggests continuous relocation of those elements to the actively growing apical part. The (137)Cs and K showed relatively weak correlations, especially in capitula and living green segments (0-10cm) of the plant (r=0.50). The strongest correlations were revealed between (137)Cs and Rb (r=0.89), and between (137)Cs and stable Cs (r=0.84). This suggests similarities between (137)Cs and Rb in uptake and relocation within the Sphagnum, but that (137)Cs differs from K. Copyright 2009 Elsevier Ltd. All rights reserved.

Uptake and accumulation of 137Cs by upland grassland soil fungi: a potential pool of Cs immobilization

International Nuclear Information System (INIS)

Dighton, J.; Clint, G.M.; Poskitt, J.

1991-01-01

Reports of high concentrations of fallout radiocaesium in basidiomycete fruit bodies after the Chernobyl nuclear reactor accident and speculation that fungi could be long-term 137 Cs accumulators led us to ask if fungi could be long-term 137 Cs accumulators. We used six common upland grassland species to try to estimate their importance in the immobilization of 137 Cs. Uptake of Cs by these species ranged from 44 to 235 nmol Cs g − 1d.w. h − 1. Efflux studies indicate that more than 40% of the Cs taken up is bound within the hyphae. We estimate that the fungal component of the soil could immobilize the total radiocaesium fallout received in upland grasslands following the Chernobyl accident

Enhanced biodegradation of diesel oil by a newly identified Rhodococcus baikonurensis EN3 in the presence of mycolic acid.

Science.gov (United States)

Lee, M; Kim, M K; Singleton, I; Goodfellow, M; Lee, S-T

2006-02-01

The aim of the present study was to isolate and characterize a bacterium, strain EN3, capable of using diesel oil as a major carbon and energy source, and to analyse the enhancement of diesel oil degradation by this organism using synthetic mycolic acid (2-hexyl-3-hydroxyldecanoic acid). An actinomycete with the ability to degrade diesel oil was isolated from oil contaminated soil and characterized. The strain had phenotypic properties consistent with its classification in the genus Rhodococcus showing a 16S rRNA gene similarity of 99.7% with Rhodococcus baikonurensis DSM 44587(T). The ability of the characterized strain to degrade diesel oil at various concentrations (1000, 5000, 10 000 and 20 000 mg l(-1)) was determined. The effect of synthetic mycolic acid on the biodegradation of diesel oil was investigated at the 20 000 mg l(-1) concentration; the surfactant was added to the flask cultures at three different concentrations (10, 50 and 100 mg l(-1)) and degradation followed over 7 days. Enhanced degradation was found at all three concentrations of the surfactant. In addition, the enhancement of diesel oil degradation by other surfactants was observed. The synthetic mycolic acid has potential for the remediation of petroleum-contaminated sites from both an economic and applied perspective as it can stimulate biodegradation at low concentrations. This study showed that the synthesized mycolic acid can be used for potential applications in the bioremediation industries, for example, in oil spill clean-up, diesel fuel remediation and biostimulation.

Photoresponse of CsPbBr3 and Cs4PbBr6 Perovskite Single Crystals.

Science.gov (United States)

Cha, Ji-Hyun; Han, Jae Hoon; Yin, Wenping; Park, Cheolwoo; Park, Yongmin; Ahn, Tae Kyu; Cho, Jeong Ho; Jung, Duk-Young

2017-02-02

High-quality and millimeter-sized perovskite single crystals of CsPbBr 3 and Cs 4 PbBr 6 were prepared in organic solvents and studied for correlation between photocurrent generation and photoluminescence (PL) emission. The CsPbBr 3 crystals, which have a 3D perovskite structure, showed a highly sensitive photoresponse and poor PL signal. In contrast, Cs 4 PbBr 6 crystals, which have a 0D perovskite structure, exhibited more than 1 order of magnitude higher PL intensity than CsPbBr 3 , which generated an ultralow photoresponse under illumination. Their contrasting optoelectrical characteristics were attributed to different exciton binding energies, induced by coordination geometry of the [PbBr 6 ] 4- octahedron sublattices. This work correlated the local structures of lead in the primitive perovskite and its derivatives to PL spectra as well as photoconductivity.

Postsynthesis Transformation of Insulating Cs4PbBr6 Nanocrystals into Bright Perovskite CsPbBr3 through Physical and Chemical Extraction of CsBr.

Science.gov (United States)

Palazon, Francisco; Urso, Carmine; De Trizio, Luca; Akkerman, Quinten; Marras, Sergio; Locardi, Federico; Nelli, Ilaria; Ferretti, Maurizio; Prato, Mirko; Manna, Liberato

2017-10-13

Perovskite-related Cs 4 PbBr 6 nanocrystals present a "zero-dimensional" crystalline structure where adjacent [PbBr 6 ] 4- octahedra do not share any corners. We show in this work that these nanocrystals can be converted into "three-dimensional" CsPbBr 3 perovskites by extraction of CsBr. This conversion drastically changes the optoelectronic properties of the nanocrystals that become highly photoluminescent. The extraction of CsBr can be achieved either by thermal annealing (physical approach) or by chemical reaction with Prussian Blue (chemical approach). The former approach can be simply carried out on a dried film without addition of any chemicals but does not yield a full transformation. Instead, reaction with Prussian Blue in solution achieves a full transformation into the perovskite phase. This transformation was also verified on the iodide counterpart (Cs 4 PbI 6 ).

Elucidation and functional characterization of CsPSY and CsUGT promoters in Crocus sativus L.

Science.gov (United States)

Bhat, Archana; Mishra, Sonal; Kaul, Sanjana; Dhar, Manoj K

2018-01-01

The dried stigmas of Crocus sativus constitute the saffron, which is considered to be the costliest spice of the world. Saffron is valuable for its constituents, which are mainly apocarotenoids. In order to enhance the production of apocarotenoids, it is imperative to understand the regulation of apocarotenoid biosynthetic pathway. In C. sativus, although the pathway has been elucidated, the information regarding the regulation of the pathwaygenes is scanty. During the present investigation, the characterization of promoters regulating the expression of two important genes i.e. CsPSY and CsUGT was performed. We successfully cloned the promoters of both the genes, which were functionally characterized in Crocus sativus and Nicotiana tabaccum. In silico analysis of the promoters demonstrated the presence of several important cis regulatory elements responding tolight, hormonesand interaction with transcription factors (TFs). Further analysis suggested the regulation of CsPSY promoter by Abscisic acid (ABA) and that of CsUGT by Gibberellic acid (GA). In addition, we also observed ABA and GA mediated modulation in the expression of significant TFs and CsPSY and CsUGT transcripts. Overall, the study addresses issues related to regulation of key genes of apocarotenoid pathway in C.sativus.

Immunogenicity of an electron beam inactivated Rhodococcus equi vaccine in neonatal foals.

Directory of Open Access Journals (Sweden)

Angela I Bordin

Full Text Available Rhodococcus equi is an important pathogen of foals that causes severe pneumonia. To date, there is no licensed vaccine effective against R. equi pneumonia of foals. The objectives of our study were to develop an electron beam (eBeam inactivated vaccine against R. equi and evaluate its immunogenicity. A dose of eBeam irradiation that inactivated replication of R. equi while maintaining outer cell wall integrity was identified. Enteral administration of eBeam inactivated R. equi increased interferon-γ production by peripheral blood mononuclear cells in response to stimulation with virulent R. equi and generated naso-pharyngeal R. equi-specific IgA in newborn foals. Our results indicate that eBeam irradiated R. equi administered enterally produce cell-mediated and upper respiratory mucosal immune responses, in the face of passively transferred maternal antibodies, similar to those produced in response to enteral administration of live organisms (a strategy which previously has been documented to protect foals against intrabronchial infection with virulent R. equi. No evidence of adverse effects was noted among vaccinated foals.

Transfer of Chernobyl-derived 134Cs, 137Cs, 131I and 103Ru from flowers to honey and pollen

International Nuclear Information System (INIS)

Bunzl, K.; Kracke, W.

1988-01-01

The activity concentrations of 137 Cs, 134 Cs, 131 I and 103 Ru were determined separately in honey and pollen samples collected from a single bee colony during several months after the deposition of Chernobyl fallout. The source of each honey and pollen sample was determined by pollen analysis. Although the activity concentrations in honey and pollen varied with time, the concentrations of 137 Cs and 134 Cs were, in general, higher in pollen than in honey. For 103 Ru and 131 I, these differences were comparatively small. The mean 131 I/ 137 Cs and 103 Ru/ 137 Cs ratios were about one order of magnitude higher in honey than in pollen. The mean 131 I/ 103 Ru ratio was about the same for honey and pollen. This observation, in the light of the corresponding nuclide ratios found in the deposition, suggests that 137 Cs, 134 Cs, 131 I and 103 Ru were taken up by the plant leaves and transported to nectar and pollen. The higher activity concentrations of 137 Cs and 134 Cs in pollen, relative to honey, indicate that these radionuclides behave analogously to potassium, which is also found in higher quantities in pollen. (author)

Relative injectivity and CS-modules

Directory of Open Access Journals (Sweden)

Mahmoud Ahmed Kamal

1994-01-01

Full Text Available In this paper we show that a direct decomposition of modules M⊕N, with N homologically independent to the injective hull of M, is a CS-module if and only if N is injective relative to M and both of M and N are CS-modules. As an application, we prove that a direct sum of a non-singular semisimple module and a quasi-continuous module with zero socle is quasi-continuous. This result is known for quasi-injective modules. But when we confine ourselves to CS-modules we need no conditions on their socles. Then we investigate direct sums of CS-modules which are pairwise relatively inective. We show that every finite direct sum of such modules is a CS-module. This result is known for quasi-continuous modules. For the case of infinite direct sums, one has to add an extra condition. Finally, we briefly discuss modules in which every two direct summands are relatively inective.

The distribution of {sup 137}Cs, K, Rb and Cs in plants in a Sphagnum-dominated peatland in eastern central Sweden

Energy Technology Data Exchange (ETDEWEB)

Vinichuk, M., E-mail: mykhailo.vinichuk@mark.slu.s [Department of Soil and Environment, Swedish University of Agricultural Sciences, SLU, P.O. Box 7014, SE-750 07 Uppsala (Sweden); Department of Ecology, Zhytomyr State Technological University, 103 Chernyakhovsky Street, 10005 Zhytomyr (Ukraine); Johanson, K.J. [Department of Soil and Environment, Swedish University of Agricultural Sciences, SLU, P.O. Box 7014, SE-750 07 Uppsala (Sweden); Rydin, H. [Department of Plant Ecology, Evolutionary Biology Centre, Uppsala University, Norbyvaegen 18D, SE-752 36 Uppsala (Sweden); Rosen, K. [Department of Soil and Environment, Swedish University of Agricultural Sciences, SLU, P.O. Box 7014, SE-750 07 Uppsala (Sweden)

2010-02-15

We record the distribution of {sup 137}Cs, K, Rb and Cs within individual Sphagnum plants (down to 20 cm depth) as well as {sup 137}Cs in vascular plants growing on a peatland in eastern central Sweden. In Calluna vulgaris{sup 137}Cs was mainly located within the green parts, whereas Andromeda polifolia, Eriophorum vaginatum and Vaccinium oxycoccos showed higher {sup 137}Cs activity in roots. Carex rostrata and Menyanthes trifoliata showed variable distribution of {sup 137}Cs within the plants. The patterns of {sup 137}Cs activity concentration distribution as well as K, Rb and Cs concentrations within individual Sphagnum plants were rather similar and were usually highest in the capitula and/or in the subapical segments and lowest in the lower dead segments, which suggests continuous relocation of those elements to the actively growing apical part. The {sup 137}Cs and K showed relatively weak correlations, especially in capitula and living green segments (0-10 cm) of the plant (r = 0.50). The strongest correlations were revealed between {sup 137}Cs and Rb (r = 0.89), and between {sup 137}Cs and stable Cs (r = 0.84). This suggests similarities between {sup 137}Cs and Rb in uptake and relocation within the Sphagnum, but that {sup 137}Cs differs from K.

Function of Nup98 subtypes and their fusion proteins, Nup98-TopIIβ and Nup98-SETBP1 in nuclear-cytoplasmic transport.

Science.gov (United States)

Saito, Shoko; Yokokawa, Takafumi; Iizuka, Gemmei; Cigdem, Sadik; Okuwaki, Mitsuru; Nagata, Kyosuke

2017-05-20

Nup98 is a component of the nuclear pore complex. The nup98-fusion genes derived by chromosome translocations are involved in hematopoietic malignancies. Here, we investigated the functions of Nup98 isoforms and two unexamined Nup98-fusion proteins, Nup98-TopIIβ and Nup98-SETBP1. We first demonstrated that two Nup98 isoforms are expressed in various mouse tissues and similarly localized in the nucleus and the nuclear envelope. We also showed that Nup98-TopIIβ and Nup98-SETBP1 are localized in the nucleus and partially co-localized with full-length Nup98 and a nuclear export receptor XPO1. We demonstrated that Nup98-TopIIβ and Nup98-SETBP1 negatively regulate the XPO1-mediated protein export. Our results will contribute to the understanding of the molecular mechanism by which the Nup98-fusion proteins induce tumorigenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

Derivation of 137Cs deposition density from measurement of 137Cs inventories in undisturbed soils

International Nuclear Information System (INIS)

Hien, P.D.; Hiep, H.T.; Quang, N.H.; Huy, N.Q.; Binh, N.T.; Hai, P.S.; Long, N.Q.; Bac, V.T

2012-01-01

The 137 Cs inventories in undisturbed soils were measured for 292 locations across the territory of Vietnam. the logarithmic inventory values were regressed against characteristics of sampling sites, such as geographical coordinates, annual rainfall and physico-chemical parameters of soil. The regression model containing latitude and annual rainfall as determinants could explain 76% of the variations in logarithmic inventory values across the territory. The model part was interpreted as the logarithmic 137 Cs deposition density. At the 95% confidence level, 137 Cs deposition density could be predicted be the model ± 7% relative uncertainty. the latitude mean 137 Cs deposition density increases northward from 237 Bq m -2 to 1097 Bq m -2 , while the corresponding values derived from the UNSCEAR (1969) global pattern are 300 Bq m -2 and 600 Bq m -2 . High 137 Cs inputs were found in high-rainfall areas in northern and central parts of the territory. (author)

Endosulfan induced alteration in bacterial protein profile and RNA yield of Klebsiella sp. M3, Achromobacter sp. M6, and Rhodococcus sp. M2.

Science.gov (United States)

Singh, Madhu; Singh, Dileep Kumar

2014-01-30

Three bacterial strains identified as Klebsiella sp. M3, Achromobacter sp. M6 and Rhodococcus sp. M2 were isolated by soil enrichment with endosulfan followed by shake flask enrichment technique. They were efficiently degrading endosulfan in the NSM (non sulfur medium) broth. Degradation of endosulfan was faster with the cell free extract of bacterial cells grown in the sulfur deficient medium (NSM) supplemented with endosulfan than that of nutrient rich medium (Luria Bertani). In the cell free extract of NSM supplemented with endosulfan as sole sulfur source, a unique band was visualized on SDS-PAGE but not with magnesium sulfate as the sole sulfur source in NSM and LB with endosulfan. Expression of a unique polypeptide band was speculated to be induced by endosulfan under sulfur starved condition. These unique polypeptide bands were identified as OmpK35 protein, sulfate binding protein and outer membrane porin protein, respectively, in Klebsiella sp. M3, Achromobacter sp. M6 and Rhodococcus sp. M2. Endosulfan showed dose dependent negative effect on total RNA yield of bacterial strains in nutrient rich medium. Absence of plasmid DNA indicated the presence of endosulfan metabolizing gene on genomic DNA. Copyright © 2013 Elsevier B.V. All rights reserved.

Accumulation of thorium and uranium by microbes. The effect of pH, concentration of metals, and time course on the accumulation of both elements using streptomyces levoris

International Nuclear Information System (INIS)

Tsuruta, Takehiko

2006-01-01

The accumulation of thorium and uranium by various microorganisms from a solution containing both metals at pH 3.5 was examined. Among the tested species, a high accumulation ability for thorium was exhibited by strains of gram-positive bacteria, such as Arthrobacter nicotianae, Bacillus megaterium, B. subtilis, Micrococcus luteus, Rhodococcus erythropolis, and Streptomyces levoris. Though uranium was accumulated in small amounts by most of microorganisms. A. nicotianae, S. flavoviridis, and S. levoris had relatively high uranium accumulation abilities. In these high performance thorium- and uranium-accumulating microorganisms, S. levoris, which accumulated the largest amount of uranium from the solution containing only uranium at pH 3.5, accumulated about 300 μmol thorium and 133 μmol uranium per gram dry weight of microbial cells from a solution containing both thorium and uranium at pH 3.5. The amount and time course of the thorium accumulation were almost unaffected by the co-existing uranium, while those of uranium were strongly affected by the co-existing thorium. The effects of pH, the thorium and uranium concentrations, and time course on both metal accumulations were also evaluated by numerical formulas. (author)

Distribution of hydrocarbon-degrading bacteria in the soil environment and their contribution to bioremediation.

Science.gov (United States)

Fukuhara, Yuki; Horii, Sachie; Matsuno, Toshihide; Matsumiya, Yoshiki; Mukai, Masaki; Kubo, Motoki

2013-05-01

A real-time PCR quantification method for indigenous hydrocarbon-degrading bacteria (HDB) carrying the alkB gene in the soil environment was developed to investigate their distribution in soil. The detection limit of indigenous HDB by the method was 1 × 10(6) cells/g-soil. The indigenous HDB were widely distributed throughout the soil environment and ranged from 3.7 × 10(7) to 5.0 × 10(8) cells/g-soil, and the ratio to total bacteria was 0.1-4.3 %. The dynamics of total bacteria, indigenous HDB, and Rhodococcus erythropolis NDKK6 (carrying alkB R2) during bioremediation were analyzed. During bioremediation with an inorganic nutrient treatment, the numbers of these bacteria were slightly increased. The numbers of HDB (both indigenous bacteria and strain NDKK6) were gradually decreased from the middle stage of bioremediation. Meanwhile, the numbers of these bacteria were highly increased and were maintained during bioremediation with an organic nutrient. The organic treatment led to activation of not only the soil bacteria but also the HDB, so an efficient bioremediation was carried out.

Examination of the role of CS{sub 2} in the CS{sub 2}/NMP mixed solvents to coal extraction

Energy Technology Data Exchange (ETDEWEB)

Shui, Hengfu; Wang, Zhicai [School of Chemistry and Chemical Engineering, Anhui University of Technology, 243002 Maanshan Anhui (China); Gao, Jinsheng [Department of Energy Resources and Chemical Engineering, East China University of Science & amp; Technology, 200237 Shanghai (China)

2006-02-15

The roles of CS{sub 2} in the CS{sub 2}/NMP mixed solvent to coal extraction and solubilization were investigated in this study. There was little effect of removing of CS{sub 2} from the solutions on the solubilities of UF coal extract and pyridine insoluble (PI) of the extract in the NMP/CS{sub 2} mixed solvent, suggesting that NMP has high enough solubilities to the UF coal extract and PI. Six Argonne different rank coals were extracted with the CS{sub 2}/NMP mixed solvent and NMP, respectively. It was found that the extraction yield difference between NMP and CS{sub 2}/NMP mixed solvent for UF coal is largely deviated from the curve obtained for the other 5 coals, suggesting that the pre-swelling of CS{sub 2} in the mixed solvent may be one of important roles for high extraction yield of UF coal in the CS{sub 2}/NMP mixed solvent. FTIR indicated that there was a strong interaction between CS{sub 2} and NMP in the CS{sub 2}/NMP mixed solvent of 1:1 volume ratio, which made the strong absorbance at 2156 cm{sup -1} in the FTIR spectra, and this interaction may disrupt the dipole based association of NMP thus making the CS{sub 2}/NMP mixed solvent lower viscosity, to penetrate more quickly into the network structure of coal, resulting in the larger solvent partner (NMP) to enter and break the stronger coal-coal interactions. (author)

Transformation of Sintered CsPbBr3 Nanocrystals to Cubic CsPbI3 and Gradient CsPbBrxI3-x through Halide Exchange.

Science.gov (United States)

Hoffman, Jacob B; Schleper, A Lennart; Kamat, Prashant V

2016-07-13

All-inorganic cesium lead halide (CsPbX3, X = Br(-), I(-)) perovskites could potentially provide comparable photovoltaic performance with enhanced stability compared to organic-inorganic lead halide species. However, small-bandgap cubic CsPbI3 has been difficult to study due to challenges forming CsPbI3 in the cubic phase. Here, a low-temperature procedure to form cubic CsPbI3 has been developed through a halide exchange reaction using films of sintered CsPbBr3 nanocrystals. The reaction was found to be strongly dependent upon temperature, featuring an Arrhenius relationship. Additionally, film thickness played a significant role in determining internal film structure at intermediate reaction times. Thin films (50 nm) showed only a small distribution of CsPbBrxI3-x species, while thicker films (350 nm) exhibited much broader distributions. Furthermore, internal film structure was ordered, featuring a compositional gradient within film. Transient absorption spectroscopy showed the influence of halide exchange on the excited state of the material. In thicker films, charge carriers were rapidly transferred to iodide-rich regions near the film surface within the first several picoseconds after excitation. This ultrafast vectorial charge-transfer process illustrates the potential of utilizing compositional gradients to direct charge flow in perovskite-based photovoltaics.

Correlations between potassium, rubidium and cesium ({sup 133}Cs and {sup 137}Cs) in sporocarps of Suillus variegatus in a Swedish boreal forest

Energy Technology Data Exchange (ETDEWEB)

Vinichuk, M., E-mail: Mykhailo.Vinichuk@slu.s [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, SE-750 07 Uppsala (Sweden); Department of Ecology, Zhytomyr State Technological University, 103 Cherniakhovsky Str., 10005 Zhytomyr (Ukraine); Rosen, K.; Johanson, K.J. [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, SE-750 07 Uppsala (Sweden); Dahlberg, A. [Department of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, P.O. Box 7026, 750 07 Uppsala (Sweden)

2011-04-15

An analysis of sporocarps of ectomycorrhizal fungi Suillus variegatus assessed whether cesium ({sup 133}Cs and {sup 137}Cs) uptake was correlated with potassium (K) or rubidium (Rb) uptake. The question was whether intraspecific correlations of Rb, K and {sup 133}Cs mass concentrations with {sup 137}Cs activity concentrations in sporocarps were higher within, rather than among, different fungal species, and if genotypic origin of sporocarps within a population affected uptake and correlation. Sporocarps (n = 51) from a Swedish forest population affected by the fallout after the Chernobyl accident were studied. The concentrations were 31.9 {+-} 6.79 g kg{sup -1} for K (mean {+-} SD, dwt), 0.40 {+-} 0.09 g kg{sup -1} for Rb, 8.7 {+-} 4.36 mg kg{sup -1} for {sup 133}Cs and 63.7 {+-} 24.2 kBq kg{sup -1} for {sup 137}Cs. The mass concentrations of {sup 133}Cs correlated with {sup 137}Cs activity concentrations (r = 0.61). There was correlation between both {sup 133}Cs concentrations (r = 0.75) and {sup 137}Cs activity concentrations (r = 0.44) and Rb, but the {sup 137}Cs/{sup 133}Cs isotopic ratio negatively correlated with Rb concentration. Concentrations of K and Rb were weakly correlated (r = 0.51). The {sup 133}Cs mass concentrations, {sup 137}Cs activity concentrations and {sup 137}Cs/{sup 133}Cs isotopic ratios did not correlate with K concentrations. No differences between, within or, among genotypes in S. variegatus were found. This suggested the relationships between K, Rb, {sup 133}Cs and {sup 137}Cs in sporocarps of S. variegatus is similar to other fungal species. - Highlights: {yields} We studied uptake of Cs ({sup 133}Cs and {sup 137}Cs), K and Rb by Suillus variegates sporocarps. {yields} Genotypic origin of fungus did not affect uptake of studied elements (isotopes). {yields} Genotypic origin did not affect correlation between Cs ({sup 133}Cs and {sup 137}Cs), K and Rb.

137Cs in northern Adriatic sediments

International Nuclear Information System (INIS)

Barisic, D.; Lulic, S.; Vdovic, N.; Vertacnik, A.; Juracic, M.

1996-01-01

The activity of 137 Cs in shallow northern Adriatic sediments was obtained on the basis of measurement results from 25 sediment box cores, sampled during the Adriatic Scientific COoperation Program (ASCOP) 16 cruise in the summer 1990. 137 Cs was determined in surface sediments (0-3 cm) and 12-15 cm-deep sediment. It was found that the lowest caesium concentrations correspond to sands, which are spread along the Croatian coast. Parallel to the Italian coast, 137 Cs concentrations in pelites are the highest. It seems that the influence of Po River is significant for 137 Cs activities in recent marine sediments along Italian coast south of Po River delta. Significantly higher 137 Cs activities in 0-3 cm sediment layer can be attributed to the deposition caused by Chernobyl accident. (author)

Reliability and Validity of the Footprint Assessment Method Using Photoshop CS5 Software.

Science.gov (United States)

Gutiérrez-Vilahú, Lourdes; Massó-Ortigosa, Núria; Costa-Tutusaus, Lluís; Guerra-Balic, Myriam

2015-05-01

Several sophisticated methods of footprint analysis currently exist. However, it is sometimes useful to apply standard measurement methods of recognized evidence with an easy and quick application. We sought to assess the reliability and validity of a new method of footprint assessment in a healthy population using Photoshop CS5 software (Adobe Systems Inc, San Jose, California). Forty-two footprints, corresponding to 21 healthy individuals (11 men with a mean ± SD age of 20.45 ± 2.16 years and 10 women with a mean ± SD age of 20.00 ± 1.70 years) were analyzed. Footprints were recorded in static bipedal standing position using optical podography and digital photography. Three trials for each participant were performed. The Hernández-Corvo, Chippaux-Smirak, and Staheli indices and the Clarke angle were calculated by manual method and by computerized method using Photoshop CS5 software. Test-retest was used to determine reliability. Validity was obtained by intraclass correlation coefficient (ICC). The reliability test for all of the indices showed high values (ICC, 0.98-0.99). Moreover, the validity test clearly showed no difference between techniques (ICC, 0.99-1). The reliability and validity of a method to measure, assess, and record the podometric indices using Photoshop CS5 software has been demonstrated. This provides a quick and accurate tool useful for the digital recording of morphostatic foot study parameters and their control.

137Cs metabolism in pregnant women

International Nuclear Information System (INIS)

Melo, D.R.; Lipsztein, J.L.; Oliveira, C.A.N.; Bertelli, L.

2000-01-01

Data from two pregnant women contaminated with 137 Cs, body burdens of 0.2 and 300 MBq, respectively at the time of the Goiania accident, were compared. The first one, with lower body burden was exposed during the fourth month of pregnancy, while the second became pregnant three years and eight months after 137 Cs intake. For the first woman 137 Cs concentrations were equal for the mother, infant and placenta, indicating an easy and homogeneous transport of 137 Cs from mother to foetus. The whole body monitoring data from the second woman, who became pregnant four years after intake, did not show a reduction in biological half-life during the pregnancy. Cs concentration in the mother was found to be 13 times higher than in the infant. One possible reason for this result is that four years after intake, Cs is supposed to be concentrated mainly in skeletal muscle tissue. During the pregnancy the blood flux becomes higher in most of the organs and tissues except brain, liver and skeletal muscle tissue. (author)

Estimation of average burnup of damaged fuels loaded in Fukushima Dai-ichi reactors by using the 134Cs/137Cs ratio method

International Nuclear Information System (INIS)

Endo, T.; Sato, S.; Yamamoto, A.

2012-01-01

Average burnup of damaged fuels loaded in Fukushima Dai-ichi reactors is estimated, using the 134 Cs/ 137 Cs ratio method for measured radioactivities of 134 Cs and 137 Cs in contaminated soils within the range of 100 km from the Fukushima Dai-ichi nuclear power plants. As a result, the measured 134 Cs/ 137 Cs ratio from the contaminated soil is 0.996±0.07 as of March 11, 2011. Based on the 134 Cs/ 137 Cs ratio method, the estimated burnup of damaged fuels is approximately 17.2±1.5 [GWd/tHM]. It is noted that the numerical results of various calculation codes (SRAC2006/PIJ, SCALE6.0/TRITON, and MVP-BURN) are almost the same evaluation values of 134 Cs/ 137 Cs ratio with same evaluated nuclear data library (ENDF-B/VII.0). The void fraction effect in depletion calculation has a major impact on 134 Cs/ 137 Cs ratio compared with the differences between JENDL-4.0 and ENDF-B/VII.0. (authors)

Waste forms based on Cs-loaded silicotitanates

International Nuclear Information System (INIS)

Balmer, M.L.; Bunker, B.C.

1995-04-01

Silicotitanate ion exchange materials are being considered for removal of radioactive Cs and Sr from tank wastes at the Hanford site. The phase evolution as a function of heat treatment temperature for several sol gel derived compositions within the Cs 2 O-SiO 2 -TiO 2 system was investigated, in order to determine if an adequate waste form can be achieved by direct thermal conversion. The Cs leach rates and Cs loss during heat treatment of select materials were measured. Some compositions which contain large amounts of Ti melt to form a glass with reasonably low aqueous leach rates. A new Cs-silicotitanate material with a structure isomorphous to pollucite was discovered. This material forms at low temperatures (700--800 C) where Cs volatility is negligible. The silicotitanate-pollucite exhibits extremely low leach rates (1.42 g/m 2 day ) at 90 C, and has been identified as a promising waste form for Cs containment

Hybridization of Single Nanocrystals of Cs4PbBr6 and CsPbBr3

OpenAIRE

Weerd, Chris de; Lin, Junhao; Gomez, Leyre; Fujiwara, Yasufumi; Suenaga, Kazutomo; Gregorkiewicz, Tom

2017-01-01

Nanocrystals of all-inorganic cesium lead halide perovskites (CsPbX3, X = Cl, Br, I) feature high absorption and efficient narrow-band emission which renders them promising for future generation of photovoltaic and optoelectronic devices. Colloidal ensembles of these nanocrystals can be conveniently prepared by chemical synthesis. However, in the case of CsPbBr3, its synthesis can also yield nanocrystals of Cs4PbBr6 and the properties of the two are easily confused. Here, we investigate in de...

Hydrolysis of nitriles by soil bacteria: variation with soil origin.

Science.gov (United States)

Rapheeha, O K L; Roux-van der Merwe, M P; Badenhorst, J; Chhiba, V; Bode, M L; Mathiba, K; Brady, D

2017-03-01

The aim of this study was to explore bacterial soil diversity for nitrile biocatalysts, in particular, those for hydrolysis of β-substituted nitriles, to the corresponding carboxamides and acids that may be incorporated into peptidomimetics. To achieve this, we needed to compare the efficiency of isolation methods and determine the influence of land use and geographical origin of the soil sample. Nitrile-utilizing bacteria were isolated from various soil environments across a 1000 km long transect of South Africa, including agricultural soil, a gold mine tailing dam and uncultivated soil. The substrate profile of these isolates was determined through element-limited growth studies on seven different aliphatic or aromatic nitriles. A subset of these organisms expressing broad substrate ranges was evaluated for their ability to hydrolyse β-substituted nitriles (3-amino-3-phenylpropionitrile and 3-hydroxy-4-phenoxybutyronitrile) and the active organisms were found to be Rhodococcus erythropolis from uncultivated soil and Rhodococcus rhodochrous from agricultural soils. The capacity for hydrolysis of β-substituted nitriles appears to reside almost exclusively in Rhodococci. Land use has a much greater effect on the biocatalysis substrate profile than geographical location. Enzymes are typically substrate specific in their catalytic reactions, and this means that a wide diversity of enzymes is required to provide a comprehensive biocatalysis toolbox. This paper shows that the microbial diversity of nitrile hydrolysis activity can be targeted according to land utilization. Nitrile biocatalysis is a green chemical method for the enzymatic production of amides and carboxylic acids that has industrial applications, such as in the synthesis of acrylamide and nicotinamide. The biocatalysts discovered in this study may be applied to the synthesis of peptidomimetics which are an important class of therapeutic compounds. © 2016 The Society for Applied Microbiology.

Plant exudates promote PCB degradation by a rhodococcal rhizobacteria

Energy Technology Data Exchange (ETDEWEB)

Toussaint, Jean-Patrick; Pham, Thi Thanh My; Barriault, Diane; Sylvestre, Michel [Instiut National de la Recherche Scientifique INRS, Laval, QC (Canada). Inst. Armand-Frappier

2012-09-15

Rhodococcus erythropolis U23A is a polychlorinated biphenyl (PCB)-degrading bacterium isolated from the rhizosphere of plants grown on a PCB-contaminated soil. Strain U23A bphA exhibited 99% identity with bphA1 of Rhodococcus globerulus P6. We grew Arabidopsis thaliana in a hydroponic axenic system, collected, and concentrated the plant secondary metabolite-containing root exudates. Strain U23A exhibited a chemotactic response toward these root exudates. In a root colonizing assay, the number of cells of strain U23A associated to the plant roots (5.7 x 105 CFU g{sup -1}) was greater than the number remaining in the surrounding sand (4.5 x 104 CFU g{sup -1}). Furthermore, the exudates could support the growth of strain U23A. In a resting cell suspension assay, cells grown in a minimal medium containing Arabidopsis root exudates as sole growth substrate were able to metabolize 2,3,4'- and 2,3',4-trichlorobiphenyl. However, no significant degradation of any of congeners was observed for control cells grown on Luria-Bertani medium. Although strain U23A was unable to grow on any of the flavonoids identified in root exudates, biphenyl-induced cells metabolized flavanone, one of the major root exudate components. In addition, when used as co-substrate with sodium acetate, flavanone was as efficient as biphenyl to induce the biphenyl catabolic pathway of strain U23A. Together, these data provide supporting evidence that some rhodococci can live in soil in close association with plant roots and that root exudates can support their growth and trigger their PCB-degrading ability. This suggests that, like the flagellated Gram-negative bacteria, non-flagellated rhodococci may also play a key role in the degradation of persistent pollutants. (orig.)

Behaviour of 134Cs in the aquatic ecosystems

International Nuclear Information System (INIS)

Xu Yinliang; Chen Chuanqun

1992-07-01

The diminution of 134 Cs in the aquatic phases and the absorption of 134 Cs by aquatic lives observe the exponential expression. i.e. Y Ae be . The relationships between the enrichment factor of 134 Cs(K) and the time(t) in the aquatic lives can be represented by a linear equation, K A + Bt. The value of K in the Alternanthera philoxeroides was about 560. That can be used for monitoring and purifying the water phase contaminated by 134 Cs. Fish can absorb 134 Cs from water phase and store it in liver and kidney. The specific activity of 134 Cs in fish flesh was low but the percentage of radioactivity was high that was about 30% of total radioactivity in the fish. River mud can strongly absorb 134 Cs and reduce the absorption by aquatic lives. It is a good adsorbent and purifying agent with low cost for treatment of 134 Cs. The K + can prevent aquatic lives from absorbing Cs + because of antagonistic function

Lag phase and biomass determination of Rhodococcus pyridinivorans GM3 for degradation of phenol

Science.gov (United States)

Al-Defiery, M. E. J.; Reddy, G.

2018-05-01

Among various techniques available for removal of phenol, biodegradation is an eco-friendly and cost effective method. Thus, it is required to understand the process of biodegradation of phenol, such as investigate on lag phase and biomass concentration. Phenol degrading bacteria were isolated from soil samples of industrial sites in enriched mineral salts medium (MSM) with phenol as a sole source of energy and carbon. One isolate of potential phenol degradation from consortium for phenol degrading studies was identified as Rhodococcus pyridinivorans GM3. Lag phase and biomass determination of R. pyridinivorans GM3 was studied with different phenol concentrations under pH 8.5 at temperature 32 Co and 200 rpm. Microbial biomass was directly proportional to increasing phenol concentration between 1.0 to 2.0 g/L with a maximum dry biomass of 1.745 g/L was noted after complete degradation of 2.0 g/L phenol in 48 hours.

New technology of CRDM-CS

International Nuclear Information System (INIS)

Yasushi Nozaki; Hiroyuki Ukon; Toshiaki Matsumura; Yoshihiro Sakurai; Sigenori Hatazawa; Hitoshi Yamagishi; Katsuji Kaneizumi; Hisashi Yasuda

2005-01-01

Control Rod Drive Mechanism Control System (CRDM-CS) for PWR Nuclear Power Plant was developed as a domestic product in 1975 and it has been applied to the commercial power plants. Since then, the CRDM-CS has been continuously improved through applying a double-hold-system, an intensified monitoring system, etc. As the result of these modifications unexpected rod drops have never occurred more than ten years in Japanese PWR plants. The system is still so high reliable, however, the technologies of employed devices are old-fashioned and we face on the difficulty to keep spare-parts these days. On the other hand, there are new movements to seek after the plant life extension of 60 years. These situations require a modernized CRDM-CS to accomplish the reliability in accordance to the plant life extension. to comply the above-mentioned object we developed a new CRDM-CS applied with following technologies; 1) Digitalized logic cabinet, 2) I.G.B.T in the main circuit of power cabinet, 3) Standardized cabinet by employing the unit structure, 4) Unnecessary DC hold power cabinet. These measures can play an important role in cost cutting and space reduction in replacing CRDM-CS. The concepts in developing the new CRDM-CS, the applied technologies to the power cabinet, the system structure and characteristics of the logic cabinet and the outline of verification test and result are discussed in this paper. (authors)

Coefficients of distribution and accumulation of K, Rb, Cs and 137Cs in the intensive poultry breeding cycle

International Nuclear Information System (INIS)

Djuric, G.; Ajdacic, N.; Institut za Nuklearne Nauke Boris Kidric, Belgrade

1984-01-01

The concentration of K,Rb,Cs and the activity level of Cs-137 in samples from the intensive poultry breeding cycle (feed, meat, eggs), under the condition of chronic alimentary contamination is presented. Concentrations of Cs and Rb were determined by non-destructive neutron activation analysis, concentration of K by atomic absorption flame photometry and activity of Cs-137 by gamma spectrometric analysis. On the basis of these results, coefficients of distribution and accumulation were calculated. The distribution coefficients of the analysed stable isotopes in meat have values close to 1, whereas for various parts of egg these coefficients vary between 0.5 and 1.5. Significant differences in Cs-137 distribution in various parts of egg were established. The values of accumulation coefficients indicate that all analysed elements selectively accumulate in the meat of young birds (broilers), and Cs-137 accumulates in the egg white as well. (orig.)

Using Multiple Paths in NoCs for Guaranteed Resource Allocation and Improved Best Effort Performance in NoCs.

NARCIS (Netherlands)

Ovadia, I.; Ha, Y.; Corporaal, H.

2005-01-01

Networks-on-Chips (NoCs) provide communication platforms to Systems-on-Chips (SoCs). In NoCs, channels are generally shared between traffic flows, resulting in contention. However, certain flows require delivery guarantees. Differentiated quality-of-service (QoS) is achieved by providing guaranteed

Diastereoselective reduction of 1-(4-fluorophenyl)-3(R)-[3-oxo-3-(4-fluorophenyl) -propyl]-4 (S)-(4-hydroxyphenyl)azetidin-2-one to Ezetimibe by the whole cell catalyst Rhodococcus fascians MO22

Czech Academy of Sciences Publication Activity Database

Kyslíková, Eva; Babiak, P.; Marešová, Helena; Palyzová, Andrea; Hajíček, J.; Kyslík, Pavel

2010-01-01

Roč. 67, 3-4 (2010), s. 266-270 ISSN 1381-1177 R&D Projects: GA MŠk 2B08064 Institutional research plan: CEZ:AV0Z50200510 Keywords : Biotransformation * Rhodococcus fascians MO22 * Ezetimibe Subject RIV: CE - Biochemistry Impact factor: 2.330, year: 2010

Modeling radionuclide Cs and C dynamics in an artificial forest ecosystem in Japan -FoRothCs ver1.0-

Directory of Open Access Journals (Sweden)

Kazuya eNishina

2015-09-01

Full Text Available Predicting the environmental fate of Cs radionuclides in forest ecosystems is important for the effective management and assessment of radioactively contaminated forest areas. A large proportion of the radioactively contaminated areas in Japan consist of forest ecosystems, and most of these areas are artificial forests that are used for timber production (e.g., Japanese cedar (Cryptomeria japonica and red pine (Pinus densiflora. Determining the long-term redistribution of 137Cs in forest ecosystems is important for estimating human doses and understanding the ecological impacts and challenges associated with managing contaminated forests. To facilitate the management and 137Cs decontamination of these forests, we developed a new open-source 137Cs cycling model, ForRothCs, that considers C cycling within forests, as well as biomass production and soil decomposition processes. For the 137Cs inventory, this model estimates the dynamics (Bq m−2 and activity (Bq kg−2 of 137Cs on a decadal time scale, primarily in the leaves, branches, stems, litter layer, and the soil. This model is based on the biomass production and the dynamics of the C cycle models. We tested the model by considering a simple scenario of forest management, i.e., thinning and harvesting, for the first five years following a fallout event. The results showed that these activities have a limited impact on the 137Cs inventory due to the rapid migration of 137Cs from vegetation to soil. Our projections also showed the examined forest management practices resulted in reduced litterfall, which in turn reduced C input to the forest floor and increased the concentration of 137Cs in the litterfall and soil organic layer. Although further validation of the ForRothCs model is required using field observation data, the model can be used to evaluate long-term 137Cs dynamics associated with commonly used forest and decontamination management scenarios.

Emulsification of crude oil by an alkane-oxidizing Rhodococcus species isolated from seawater

Energy Technology Data Exchange (ETDEWEB)

Bredholt, H.; Bruheim, P.; Eimhjellen, K. [Norwegian Univ. of Scince and Technology, Trondheim (Norway); Josefsen, K.; Vatland, A. [SINTEF SI, Oslo (Norway). Industrial Chemistry Div.

1998-04-01

A Rhodococcus species, which has proven to be the best of 99 oil-emulsifying bacteria isolated from seawater, was characterized. This bacterium produced very stable oil-in-water emulsions from different crude oils with various content of aliphatic and aromatic compounds, by utilizing C{sub 1}1 and C{sub 3}3 n-alkanes as carbon and energy sources. Bacteria that produce stable emulsions are often able to adhere strongly to hydrocarbons or hydrophobic surfaces. It was at these surfaces that extensive emulsification of the residual oil and accumulation of acidic oxidation products occurred. The acidic products were consumed in a second step. This step was characterized by linear growth and an increasing number of cells growing in the water phase. The most extensive emulsification occurred at the end of the exponential phase. There was no evidence of surfactants at the end of the exponential phase, however, a polymeric compound with emulsifying activity, tightly bound to the oil droplets, was isolated, suggesting that the emulsification resulted from the release of the hydrophobic cell surface discarded during growth limitations. 38 refs., 7 figs.

Cholesterol oxidase (ChoE) is not important in the virulence of Rhodococcus equi.

Science.gov (United States)

Pei, Yanlong; Dupont, Chris; Sydor, Tobias; Haas, Albert; Prescott, John F

2006-12-20

To analyze further the role in virulence of the prominent cholesterol oxidase (ChoE) of Rhodococcus equi, an allelic exchange choE mutant from strain 103+ was constructed and assessed for virulence in macrophages, in mice, and in foals. There was no difference between the mutant and parent strain in cytotoxic activity for macrophages or in intra-macrophage multiplication. No evidence of attenuation was obtained in macrophages and in mice, but there was slight attenuation apparent in four intra-bronchially infected foals compared to infection of four foals with the virulent parent strain, based on a delayed rise in temperature of the choE-mutant infected foals. However, bacterial colony counts in the lung 2 weeks after infection were not significantly different, although there was a slight but non-significant (P=0.12) difference in lung:body weight ratio of the choE mutant versus virulent parent infected foals (mean 2.67+/-0.25% compared to 4.58+/-0.96%). We conclude that the cholesterol oxidase is not important for the virulence of R. equi.

Luminescent CsPbI.sub.3./sub. and Cs.sub.4./sub.PbI.sub.6./sub. aggregates in annealed CsI:Pb crystals

Czech Academy of Sciences Publication Activity Database

Babin, V.; Fabeni, P.; Nikl, Martin; Nitsch, Karel; Pazzi, G.P.; Zazubovich, S.

2001-01-01

Roč. 226, č. 2 (2001), s. 419-428 ISSN 0370-1972 Institutional research plan: CEZ:AV0Z1010914 Keywords : CsPbI 3 * Cs 4 PbI 6 * nanoaggregates * luminescence Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.873, year: 2001

Cs2UPd3Se6

Directory of Open Access Journals (Sweden)

George N. Oh

2011-02-01

Full Text Available Dicaesium uranium(IV tripalladium(II hexaselenide, Cs2UPd3Se6, crystallizes in the space group Fmmm in the Ba2NaCu3O6 structure type. The asymmetric unit comprises the following atoms with site symmetries as shown: U1 (mm2, Cs1 (222, Cs2 (m2m, Pd1 (.m., Pd2 (2mm, Se1 (m.., and Se2 (1. This layered structure contains six edge-sharing square-planar [PdSe4] units that form a hexagon. These, in turn, edge-share with [USe6] trigonal–prismatic units, forming an extended layer parallel to (010. The layers are stacked along [010]. They are staggered, and are separated by the Cs atoms. The Cs atoms are either coordinated in a square antiprism of Se atoms or are ten-coordinate, with one square face and the opposite face hexagonal.

Properties of Cs-intercalated single wall carbon nanotubes investigated by 133Cs Nuclear Magnetic resonance

KAUST Repository

Schmid, Marc R.; Mahfouz, Remi; Bouhrara, Mohamed; Saih, Youssef; Mehring, Michael; Basset, Jean-Marie; Goze-Bac, Christophe; Abou-Hamad, Edy

2012-01-01

present within the carbon nanotube bundles. At high concentrations, the Cs (β)+ ions seem to occupy well defined positions relative to the carbon lattice. As a matter of fact, the Korringa relaxation behavior suggests a strong hyperfine coupling between Cs

Potential value of Cs-137 capsules

Energy Technology Data Exchange (ETDEWEB)

Bloomster, C.H.; Brown, D.R.; Bruno, G.A.; Hazelton, R.F.; Hendrickson, P.L.; Lezberg, A.J.; Tingey, G.L.; Wilfert, G.L.

1985-04-01

We determined the value of Cs-137 compared to Co-60 as a source for the irradiation of fruit (apples and cherries), pork and medical supplies. Cs-137, in the WESF capsule form, had a value of approximately $0.40/Ci as a substitute for Co-60 priced at approximately $1.00/Ci. The comparison was based on the available curies emitted from the surface of each capsule. We developed preliminary designs for fourteen irradiation facilities; seven were based on Co-60 and seven were based on Cs-137. These designs provided the basis for estimating capital and operating costs which, in turn, provided the basis for determining the value of Cs-137 relative to Co-60 in these applications. We evaluated the effect of the size of the irradiation facility on the value of Cs-137. The cost of irradiation is low compared to the value of the product. Irradiation of apples for disinfestation costs $.01 to .02 per pound. Irradiation for trichina-safe pork costs $.02 per pound. Irradiation of medical supplies for sterilization costs $.07 to .12 per pound. The cost of the irradiation source, either Co-60 or Cs-137, contributed only a minor amount to the total cost of irradiation, about 5% for the fruit and hog cases and about 20% for the medical supply cases. We analyzed the sensitivity of the irradiation costs and Cs-137 value to several key assumptions.

Potential value of Cs-137 capsules

International Nuclear Information System (INIS)

Bloomster, C.H.; Brown, D.R.; Bruno, G.A.; Hazelton, R.F.; Hendrickson, P.L.; Lezberg, A.J.; Tingey, G.L.; Wilfert, G.L.

1985-04-01

We determined the value of Cs-137 compared to Co-60 as a source for the irradiation of fruit (apples and cherries), pork and medical supplies. Cs-137, in the WESF capsule form, had a value of approximately $0.40/Ci as a substitute for Co-60 priced at approximately $1.00/Ci. The comparison was based on the available curies emitted from the surface of each capsule. We developed preliminary designs for fourteen irradiation facilities; seven were based on Co-60 and seven were based on Cs-137. These designs provided the basis for estimating capital and operating costs which, in turn, provided the basis for determining the value of Cs-137 relative to Co-60 in these applications. We evaluated the effect of the size of the irradiation facility on the value of Cs-137. The cost of irradiation is low compared to the value of the product. Irradiation of apples for disinfestation costs $.01 to .02 per pound. Irradiation for trichina-safe pork costs $.02 per pound. Irradiation of medical supplies for sterilization costs $.07 to .12 per pound. The cost of the irradiation source, either Co-60 or Cs-137, contributed only a minor amount to the total cost of irradiation, about 5% for the fruit and hog cases and about 20% for the medical supply cases. We analyzed the sensitivity of the irradiation costs and Cs-137 value to several key assumptions

Biodesulfurization of Naphthothiophene and Benzothiophene through Selective Cleavage of Carbon-Sulfur Bonds by Rhodococcus sp. Strain WU-K2R

Science.gov (United States)

Kirimura, Kohtaro; Furuya, Toshiki; Sato, Rika; Ishii, Yoshitaka; Kino, Kuniki; Usami, Shoji

2002-01-01

Naphtho[2,1-b]thiophene (NTH) is an asymmetric structural isomer of dibenzothiophene (DBT), and in addition to DBT derivatives, NTH derivatives can also be detected in diesel oil following hydrodesulfurization treatment. Rhodococcus sp. strain WU-K2R was newly isolated from soil for its ability to grow in a medium with NTH as the sole source of sulfur, and growing cells of WU-K2R degraded 0.27 mM NTH within 7 days. WU-K2R could also grow in the medium with NTH sulfone, benzothiophene (BTH), 3-methyl-BTH, or 5-methyl-BTH as the sole source of sulfur but could not utilize DBT, DBT sulfone, or 4,6-dimethyl-DBT. On the other hand, WU-K2R did not utilize NTH or BTH as the sole source of carbon. By gas chromatography-mass spectrometry analysis, desulfurized NTH metabolites were identified as NTH sulfone, 2′-hydroxynaphthylethene, and naphtho[2,1-b]furan. Moreover, since desulfurized BTH metabolites were identified as BTH sulfone, benzo[c][1,2]oxathiin S-oxide, benzo[c][1,2]oxathiin S,S-dioxide, o-hydroxystyrene, 2-(2′-hydroxyphenyl)ethan-1-al, and benzofuran, it was concluded that WU-K2R desulfurized NTH and BTH through the sulfur-specific degradation pathways with the selective cleavage of carbon-sulfur bonds. Therefore, Rhodococcus sp. strain WU-K2R, which could preferentially desulfurize asymmetric heterocyclic sulfur compounds such as NTH and BTH through the sulfur-specific degradation pathways, is a unique desulfurizing biocatalyst showing properties different from those of DBT-desulfurizing bacteria. PMID:12147483

Water culture of the rice containing Cs-137

International Nuclear Information System (INIS)

Choi, Yong Ho; Keum, Dong Kwon; Lim, Kwang Muk; Jun, In; Park, Doo Won

2008-10-01

Pot experiments were carried out in a greenhouse in order to produce Cs-137-containing rice seeds as a source material for use in manufacturing reference rice samples of a high Cs-137 activity. Two kinds of soil were used and two pots were prepared for each kind of soil. Rice plants were water-cultured in the pots and Cs-137 was applied to the surface water to induce a Cs-137 contamination of rice seeds via a plant uptake of Cs-137. Mature rice plants were harvested and Cs-137-containing rice seeds were obtained after some treatment of the harvested plants. These produced rice seeds are going to be provided for the KRISS so as to be used in manufacturing reference rice samples for Cs-137

Thermal, conductivity, NMR, and Raman spectroscopic measurements and phase diagram of the Cs2S2O7-CsHSO4 system

DEFF Research Database (Denmark)

Rasmussen, Søren Birk; Hama, Hind; Lapina, Olga

2003-01-01

The conductivity of the binary system CS2S2O7-CsHSO4 has been measured at 20 different molten compositions in the full composition range and in the temperature range 430-750 K. From the obtained liquidus-solidus phase transition temperatures, the phase diagram has been constructed. It is of the s......The conductivity of the binary system CS2S2O7-CsHSO4 has been measured at 20 different molten compositions in the full composition range and in the temperature range 430-750 K. From the obtained liquidus-solidus phase transition temperatures, the phase diagram has been constructed...... from the NMR measurements on CsHSO4, CS2S2O7, and Cs2S2O7-CsHSO4 mixtures. For 11 selected compositions covering the entire composition range of the CS2S2O7-CsHSO4 binary system, the conductivity of the molten state has been expressed by equations of the form k(X) = A(X) + B(X)(T - T-m) + C(X)(T - T...

Determination of /sup 131/I, /sup 134/Cs, /sup 137/Cs in grass and cheese after Chernobyl accident in Austria

Energy Technology Data Exchange (ETDEWEB)

Teherani, D K

1987-09-14

Various samples from Styria (grass) and Salzburg (cheese) were analyzed for /sup 131/I, /sup 134/Cs and /sup 137/Cs concentration during April - July 1986 by ..gamma..-ray spectroscopy. The concentrations are reported in nCi kg/sup -1/ wet weight. The values found for /sup 131/I were 0.2-17.2 (grass), 0.1-0.5 (cheese), for /sup 134/Cs 1.1-6.2 (grass), 0.2-1.3 (cheese), for /sup 137/Cs 1.6-15.7 (grass), 0.3-2.2 (cheese). While radioactivity of /sup 131/I, /sup 134/Cs and /sup 137/Cs in cheese samples increased from May to June, it decreased in grass samples from May to July. (author) 5 refs

Management of Rhodococcus equi pneumonia in foals

Directory of Open Access Journals (Sweden)

Johns I

2013-11-01

Full Text Available Imogen Johns Department of Clinical Sciences and Services, Royal Veterinary College, North Mymms, UK Abstract: Rhodococcus equi, a gram-positive facultative intracellular bacterial pathogen, is the most important cause of pneumonia in foals aged 3 weeks to 5 months. The disease occurs worldwide, resulting in significant morbidity and mortality on endemically affected farms. Foals appear to become infected early in life, but clinical signs are typically delayed until 1–3 months of age because of the insidious nature of the disease. Although pneumonia is the most common clinical manifestation, up to 74% of foals may concurrently have extrapulmonary disorders, including both extrapulmonary infections (abdominal abscessation, colitis, osteomyelitis and immune-mediated disorders (nonseptic synovitis, uveitis. Diagnosis is based on the combination of clinical signs and abnormalities on hematologic screening and thoracic imaging in an appropriately aged foal and is confirmed by bacteriologic culture of the organism. Management of R. equi infections, in particular on farms with endemic disease, combines appropriate treatment of affected foals with preventative measures targeted at preventing infection and identifying foals before the development of severe disease. The combination of rifampin and a macrolide antimicrobial is recommended for treatment, as the combination is synergistic, reaches high intracellular concentrations, and should minimize the development of antimicrobial resistance. The prognosis for survival for foals with R. equi pneumonia is good, especially in foals mildly or subclinically affected, as is the prognosis for future athletic performance. Screening for early identification before the development of clinical signs has been advocated on endemically affected farms, although the most appropriate method, the timing of screening, and the selection of foals requiring treatment have yet to be determined. Recent evidence suggests that

Magnetophoretic separation ICP-MS immunoassay using Cs-doped multicore magnetic nanoparticles for the determination of salmonella typhimurium.

Science.gov (United States)

Jeong, Arong; Lim, H B

2018-02-01

In this work, a magnetophoretic separation ICP-MS immunoassay using newly synthesized multicore magnetic nanoparticles (MMNPs) was developed for the determination of salmonella typhimurium (typhi). The uniqueness of this method was the use of MMNPs doped with Cs for both separation and detection, which enable us to achieve fast analysis, high sensitivity, and good reliability. For demonstration, heat-killed typhi in a phosphate buffer solution was determined by ICP-MS after the MMNP-typhi reaction product was separated from unreacted MMNPs in a micropipette tip filled with 25% polyethylene glycol through magnetophoretic separation. The calibration curve obtained by plotting 133 Cs intensity vs. the number of synthetic standard, showed a coefficient of determination (R 2 ) of 0.94 with a limit of detection (LOD) of 102 cells/mL without cell culturing. Excellent recoveries, between 98-100%, were obtained from four replicates and compared with a sandwich-type ICP-MS immunoassay for further confirmation. Copyright © 2017 Elsevier B.V. All rights reserved.

Calculation of inelastic cross sections for H+ + Cs → H(n=2) + Cs+

International Nuclear Information System (INIS)

Valance, A.; Spiess, G.

1975-01-01

The cross sections for the processes H + +Cs → H(2p and 2s) +Cs + were calculated in the center of mass energy range 250--2400 eV using a simple pseudopotential formalism for the potential curves and coupling matrix elements and a perturbed stationary state (pss) formulation for the calculation of the cross sections. The results are found to be in reasonable agreement with experiment. (auth)

Absolute activity measurements with the windowless 4π-CsI(Tl)-sandwich spectrometer

International Nuclear Information System (INIS)

Denecke, B.

1994-01-01

The windowless 4π-CsI(Tl)-sandwich spectrometer consists of two scintillation crystals sandwiching radioactive sources deposited on thin plastic foils. This configuration has a solid angle very close to 4π sr. The detectors are sensitive to charged particles with energies > 15 keV and measure photons of 15-200 keV with a probability > 98%. Disintegration rates of samples of radionuclides with complex decay modes can be determined directly from the measured count rates with uncertainties below 0.3%. Radionuclide solutions of 57 Co, 109 Cd, 125 I, 152 Eu and 192 Ir were standardised, partly in the framework of international comparisons. A detailed description of the spectrometer and the measurement procedure is given. (orig.)

Absolute activity measurements with the windowless 4π-CsI(Tl)-sandwich spectrometer

Science.gov (United States)

Denecke, B.

1994-01-01

The windowless 4π-CsI(Tl)-sandwich spectrometer consists of two scintillation crystals sandwiching radioactive sources deposited on thin plastic foils. This configuration has a solid angle very close to 4π sr. The detectors are sensitive to charged particles with energies > 15 keV and measure photons of 15-200 keV with a probability > 98%. Disintegration rates of samples of radionuclides with complex decay modes can be determined directly from the measured count rates with uncertainties below 0.3%. Radionuclide solutions of 57Co, 109Cd, 125I, 152Eu and 192Ir were standardised, partly in the framework of international comparisons. A detailed description of the spectrometer and the measurement procedure is given.

Influence of water management and fertilizer application on "1"3"7Cs and "1"3"3Cs uptake in paddy rice fields

International Nuclear Information System (INIS)

Wakabayashi, Shokichi; Itoh, Sumio; Kihou, Nobuharu; Matsunami, Hisaya; Hachinohe, Mayumi; Hamamatsu, Shioka; Takahashi, Shigeru

2016-01-01

Cesium-137 derived from the Tokyo Electric Power Company's Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident contaminated large areas of agricultural land in Eastern Japan. Previous studies before the accident have indicated that flooding enhances radiocesium uptake in rice fields. We investigated the influence of water management in combination with fertilizers on "1"3"7Cs concentrations in rice plants at two fields in southern Ibaraki Prefecture. Stable Cs ("1"3"3Cs) in the plants was also determined as an analogue for predicting "1"3"7Cs behavior after long-term aging of soil "1"3"7Cs. The experimental periods comprised 3 y starting from 2012 in one field, and 2 y from 2013 in another field. These fields were divided into three water management sections: a long-flooding section without midsummer drainage, and medial-flooding, and short-flooding sections with one- or two-week midsummer drainage and earlier end of flooding than the long-flooding section. Six or four types of fertilizer subsections (most differing only in potassium application) were nested in each water management section. Generally, the long-flooding treatment led to higher "1"3"7Cs and "1"3"3Cs concentrations in both straw and brown rice than medial- and short-flooding treatments, although there were some notable exceptions in the first experimental year at each site. Effects of differing potassium fertilizer treatments were cumulative; the effects on "1"3"7Cs and "1"3"3Cs concentrations in rice plants were not obvious in 2012 and 2013, but in 2014, these concentrations were highest where potassium fertilizer had been absent and lowest where basal dressings of K had been tripled. The relationship between "1"3"7Cs and "1"3"3Cs in rice plants was not correlative in the first experimental year at each site, but correlation became evident in the subsequent year(s). This study demonstrates a novel finding that omitting midsummer drainage and/or delaying drainage during the grain-filling period

Study of Cs recovery by extraction chromatography (2)

International Nuclear Information System (INIS)

Hoshi, Harutaka; Zhang, Anyun; Uchida, Hiromi; Kuraoka, Etsushu

2005-02-01

In order to apply CalixR14 extractant to extraction chromatography for Cs separation, basic characteristics of CalixR14 adsorbent were studied. CalixR14 impregnated resin and CalixR14 + TBP impregnated resin were prepared. CalixR14 extractant showed no adsorption for Cs by liquid-liquid extraction and CalixR14 impregnated resin also showed no adsorption for Cs. Therefore, it is concluded that CalixR14 itself has no affinity for Cs. On the other hand, Cs was adsorbed onto CalixR14-TBP impregnated resin from a concentrated nitric acid solution. The distribution coefficients of Cs were more than 10 cm 3 /g from 2 to 6 M nitric acid. While Rb showed week adsorption, Na, K, Sr and La showed no adsorption and separation factor was over 100. A slight amount of CalixR14 and TBP was leaked from impregnated resin into the aqueous phase. Separation from simulated liquid waste was carried out by using a column packed with CalixR14-TBP adsorbent. Na, K, Sr and La were not adsorbed onto the column, however, Cs and Rb were adsorbed onto the column. Cs and Rb were eluted from the column by water. Cs and Rb were quantitatively recovered. (author)

Radiation doses for Marshall Islands Atolls affected by U.S. nuclear testing: all exposure pathways, remedial measures, and environmental loss of (137)Cs.

Science.gov (United States)

Robison, William L; Hamilton, Terry F

2010-01-01

Radiation doses calculated for people resettling Bikini Island at Bikini Atoll, Enjebi Island at Enewetak Atoll, Rongelap Island at Rongelap Atoll, and Utrōk Island at Utrōk Atoll are presented. Residence is assumed to begin in 2010. In previous dose assessments it was shown that (137)Cs accounts for about 98% of the total dose for returning residents. About 85 to 90% (depending on the atoll) is via consumption of locally grown foods containing (137)Cs, and about 10 to 15% is due to external exposure from (137)Cs in the soil. These assessments were made using only the radiological half-life of (137)Cs (30.1 y). We have shown since that there is an environmental loss of (137)Cs from soil to groundwater that results in a more rapid loss of (137)Cs from the atoll ecosystem. The mean effective half-life of (137)Cs at the atolls is 8.5 y. Moreover, treatment of coconut trees with potassium (K) reduces (137)Cs concentration in drinking coconut meat at Bikini Atoll to about 5% of pretreatment concentrations. The magnitude of reduction is dependent on the concentration of (137)Cs in soil, and thereby in food crops, and is less for Enjebi and Rongelap Islands than for Bikini Island. Treatment of food crops and fruit trees with K and removal of the top 15 cm of soil around houses and community buildings prior to construction to reduce external exposure where people spend most of their time has been presented to the communities as a "Combined Option" remediation strategy. Doses presented here are calculated using the Combined Option, effective half-life of (137)Cs at the atolls, and a diet of both imported and local foods. The average natural background dose in the Marshall Islands, plus the anthropogenic nuclear test-related dose at Bikini, Enjebi, and Rongelap Islands, is less for each of the islands than the average background dose in the U.S. and Europe.

Vertical profile of 137Cs in soil.

Science.gov (United States)

Krstić, D; Nikezić, D; Stevanović, N; Jelić, M

2004-12-01

In this paper, a vertical distribution of 137Cs in undisturbed soil was investigated experimentally and theoretically. Soil samples were taken from the surroundings of the city of Kragujevac in central Serbia during spring-summer of 2001. The sampling locations were chosen in such a way that the influence of soil characteristics on depth distribution of 137Cs in soil could be investigated. Activity of 137Cs in soil samples was measured using a HpGe detector and multi-channel analyzer. Based on vertical distribution of 137Cs in soil which was measured for each of 10 locations, the diffusion coefficient of 137Cs in soil was determined. In the next half-century, 137Cs will remain as the source of the exposure. Fifteen years after the Chernobyl accident, and more than 30 years after nuclear probes, the largest activity of 137Cs is still within 10 cm of the upper layer of the soil. This result confirms that the penetration of 137Cs in soil is a very slow process. Experimental results were compared with two different Green functions and no major differences were found between them. While both functions fit experimental data well in the upper layer of soil, the fitting is not so good in deeper layers. Although the curves obtained by these two functions are very close to each other, there are some differences in the values of parameters acquired by them.

The 134Cs uptake by sunflower (Helianthus anuus, Less) cultivated on soil contaminated with 134Cs

International Nuclear Information System (INIS)

Poppy Intan Tjahaja; Putu Sukmabuana

2008-01-01

One of the methods for remediation of contaminated environment is phytoremediation techniques, i.e. the environmental remediation using plants. In this research the bioavailability of sunflower plant (Helianthus anuus, Less) in radiocaesium uptake from soil was studied for being considered as a phytoremediator later. Sunflower plants were cultivated on soil contaminated with 134 Cs with the concentrations of 29,3 kBq/kg ; 117,2 kBq/kg ; 557 kBq/kg for 45 days. As control the sunflowers were also cultivated on non contaminated soil. Observation was carried out every 5 days by sampling 3 plants and soils. The plant and soil samples were dried using infra red lamp for 24 hours, and then counted using gamma spectrometer. The counting results i.e. 134 Cs concentration on soil and plant parts were then analyzed to obtain transfer factor (TF) values. The highest TF values was reached on 26 th day, i.e. 0,87; 1,89 ; 2,82 for initial soil 134 Cs concentrations of 29,3 Bq/g ; 117,2 Bq/g ; 557 Bq/g, respectively. The TF values obtained expressed the capability of plants to accumulate 134 Cs from soils. The observation to the plants growth showed that the plants grew normally on the 134 Cs contaminated soil until the concentration of 557 Bq/g. The sunflower can be considered to be phytoremediator of andosol soil contaminated with Cs radionuclides. (author)

Enzymatic degradation of aliphatic nitriles by Rhodococcus rhodochrous BX2, a versatile nitrile-degrading bacterium.

Science.gov (United States)

Fang, Shumei; An, Xuejiao; Liu, Hongyuan; Cheng, Yi; Hou, Ning; Feng, Lu; Huang, Xinning; Li, Chunyan

2015-06-01

Nitriles are common environmental pollutants, and their removal has attracted increasing attention. Microbial degradation is considered to be the most acceptable method for removal. In this work, we investigated the biodegradation of three aliphatic nitriles (acetonitrile, acrylonitrile and crotononitrile) by Rhodococcus rhodochrous BX2 and the expression of their corresponding metabolic enzymes. This organism can utilize all three aliphatic nitriles as sole carbon and nitrogen sources, resulting in the complete degradation of these compounds. The degradation kinetics were described using a first-order model. The degradation efficiency was ranked according to t1/2 as follows: acetonitrile>trans-crotononitrile>acrylonitrile>cis-crotononitrile. Only ammonia accumulated following the three nitriles degradation, while amides and carboxylic acids were transient and disappeared by the end of the assay. mRNA expression and enzyme activity indicated that the tested aliphatic nitriles were degraded via both the inducible NHase/amidase and the constitutive nitrilase pathways, with the former most likely preferred. Copyright © 2015 Elsevier Ltd. All rights reserved.

SR-XRF imaging of Cs highly accumulated in vegetables

International Nuclear Information System (INIS)

Nakai, Izumi; Oda, Nahoko; Terada, Yasuko

2011-01-01

Accumulation of Cs in vegetables was studied with regard to the remediation of radioactive Cs from a nuclear plant accident in Fukushima. It was found that Brassica oleracea var. capitata, Brassica campestris var. perviridis, and Lactuca sativa accumulated Cs to a level of more than 10000 ppm (dry weight) when they were cultivated in 1 mM Cs solution. Two-dimensional distributions of Cs were revealed by SR-XRF imaging showing a homogeneous distribution of Cs in the plant bodies. (author)

Radioecological studies of 137Cs in limnological ecosystems. Biochemical states of 137Cs accumulated in killifish (Medaka, Oryzias latipes) meat

International Nuclear Information System (INIS)

Miyake, Sadaaki; Motegi, Misako; Oosawa, Takashi; Nakazawa, Kiyoaki; Izumo, Yoshiro; Nakamura, Fumio.

1997-01-01

Biochemical states of 137 Cs accumulated in killifish's (Medaka, Oryzias latipes) meat were investigated in order to elucidate the accumulation mechanism of the radionuclide in goldfish, Carassius auratus auratus, examined in our preceding report. Most of 137 Cs radioactivity in the killifish's raw meat accumulated this radionuclide in the radioactive freshwater, were found in the non-protein nitrogenous compound (NPNC) fraction (>92%), also in the killifish's control raw meat mixed with 137 Cs, the difference between both meat samples was not clear. As the results of gel filtration profiles on Sephadex G-25 for the NPNC fraction of these meats, each only one radioactive peak was shown, also similar to 137 CsCl solution. Moreover, these peaks appeared at the same position. On the other hand, the peak positions absorbed at OD 280nm in the samples were different from those of each radioactive peak. It was so suggested that 137 Cs accumulated in the killifish's meat was shown not to be binding to protein's composition. Furthermore, as the results on thin-layer chromatography, ion-exchange resin chromatography and reaction with 137 Cs in samples and ammonium phosphomolybdate, 137 Cs in the NPNC fraction of the killifish's meat was not almost different from those of each control and 137 CsCl solution. (author)

Comparison of CsI(Tl) and CsI(Na) partially slotted crystals for high-resolution SPECT imaging

International Nuclear Information System (INIS)

Giokaris, N.; Loudos, G.; Maintas, D.; Karabarbounis, A.; Lembesi, M.; Spanoudaki, V.; Stiliaris, E.; Boukis, S.; Sakellios, N.; Karakatsanis, N.; Gektin, A.; Boyarintsev, A.; Pedash, V.; Gayshan, V.

2006-01-01

Dedicated systems based on Position Sensitive Photomultiplier Tubes (PSPMTs) coupled to scintillators, have been used over the past years for the construction of compact systems, suitable for applications such as small animal imaging and small organs imaging. Most of the proposed systems are based on fully pixelized scintillators. Previous studies have shown that partially slotted scintillators offer a good compromise between cost, energy resolution and spatial resolution. In this work, the performance of two sets of CsI(Tl) and CsI(Na) partially slotted crystals is compared. Initial results show that CsI(Tl) scintillators are more suitable for gamma-ray detection, since their performance in terms of sensitivity, spatial and energy resolution is superior than that of CsI(Na)

CsI and some new photocathodes

International Nuclear Information System (INIS)

Anderson, D.F.; Kwan, S.; Peskov, V.

1993-06-01

A discussion of the possible sources of discrepancies in the measurements of the quantum efficiency of CsI photocathodes is presented. We propose that the major causes for disagreements in QE are due to the QE dependence on the current density extracted from the photocathode, on the electric field, and on the temperature of the photocathode. Preliminary results on TMAE enhanced GaAs and Si, plus TMAE protected CsTe and SbCs photocathodes, operated in gas, are also presented

137Cs distribution in guava trees

International Nuclear Information System (INIS)

Mosquera, B.; Veiga, R.; Mangia, L.; Carvalho, C.; Estellita, L.; Uzeda, D.; Facure, A.; Violini, B.; Anjos, R.M.

2004-01-01

This paper presents results of 137 Cs concentration measured from a guava tree cultivated after the first decontamination work of one of the sites where the worst Brazilian radiological accident occurred. The present work aims to verify how the 137 Cs is transported and distributed along the tropical trees. Bi-dimensional analyses of the radial distribution of 137 Cs in the main trunk are also presented. Neither symmetrical nor homogeneous behaviors of the specific activity distribution in the tree rings were observed. (author)

Coordination polyhedra CsCln in crystals

International Nuclear Information System (INIS)

Serezhkin, V.N.; Serezhkina, L.B.

1999-01-01

Characteristics of the Voronoi-Dirichlet polyhedrons are estimated for 133 crystallographic cesium atoms in chlorides Cs x M y Cl z (M=Cd, Sc, V, Nb, Mo, W, Ru, Re, etc.). It is found that cesium atoms have coordination numbers 6,8,9,10, 11 and 12 as regards the chlorine atoms. The results of cesium atom coordination sphere examination by the crossing spheres method are presented. Metal-metal interactions (including Cs-Cs) in the structure of certain chlorides are revealed

CS EMISSION NEAR MIR-BUBBLES

International Nuclear Information System (INIS)

Watson, C.; Devine, Kathryn; Quintanar, N.; Candelaria, T.

2016-01-01

We survey 44 young stellar objects located near the edges of mid-IR-identified bubbles in CS (1–0) using the Green Bank Telescope. We detect emission in 18 sources, indicating young protostars that are good candidates for being triggered by the expansion of the bubble. We calculate CS column densities and abundances. Three sources show evidence of infall through non-Gaussian line-shapes. Two of these sources are associated with dark clouds and are promising candidates for further exploration of potential triggered star formation. We obtained on-the-fly maps in CS (1–0) of three sources, showing evidence of significant interactions between the sources and the surrounding environment

CS EMISSION NEAR MIR-BUBBLES

Energy Technology Data Exchange (ETDEWEB)

Watson, C. [Manchester University, Department of Physics, 604 E. College Ave., North Manchester, IN 46962 (United States); Devine, Kathryn [College of Idaho, Department of Physics, 2112 Cleveland Blvd, Caldwell, ID 83605 (United States); Quintanar, N. [Texas A and M University, Department of Nuclear Engineering, 401 Joe Routt Blvd, College Station, TX 77843 (United States); Candelaria, T., E-mail: cwatson@manchester.edu, E-mail: KDevine@collegeofidaho.edu, E-mail: nrquintanar@tamu.edu, E-mail: tcandela@nmt.edu [New Mexico Institute of Mining and Technology, Department of Physics, 801 Leroy Place, Socorro, NM 87801 (United States)

2016-02-10

We survey 44 young stellar objects located near the edges of mid-IR-identified bubbles in CS (1–0) using the Green Bank Telescope. We detect emission in 18 sources, indicating young protostars that are good candidates for being triggered by the expansion of the bubble. We calculate CS column densities and abundances. Three sources show evidence of infall through non-Gaussian line-shapes. Two of these sources are associated with dark clouds and are promising candidates for further exploration of potential triggered star formation. We obtained on-the-fly maps in CS (1–0) of three sources, showing evidence of significant interactions between the sources and the surrounding environment.

Fractionation of 137Cs and Pu in natural peatland

International Nuclear Information System (INIS)

Mihalík, Ján; Bartusková, Miluše; Hölgye, Zoltán; Ježková, Tereza; Henych, Ondřej

2014-01-01

High Cs-137 concentrations in plants growing on peatland inspired us to investigate the quantity of its bioavailable fraction in natural peat. Our investigation aims to: a) estimate the quantity of bioavailable Cs-137 and Pu present in peat, b) verify the similarity of Cs-137 and K-40 behaviours, and c) perform a quantification of Cs-137 and Pu transfer from peat to plants. We analysed the vertical distribution of Cs-137 and Pu isotopes in the peat and their concentrations in plants growing on these places. Bioavailability of radionuclides was investigated by sequential extraction. Sequential analyses revealed that it was the upper layer which contained the majority of Cs-137 in an available form while deeper layers retained Cs-137 in immobile fractions. We can conclude that 18% of all Cs-137 in the peat is still bioavailable. Despite of the low quantity of bioavailable fraction of Cs-137 its transfer factor reached extremely high values. In the case of Pu, 64% of its total amount was associated with fulvic/humic acids which resulted in the high transfer factor from peat to plants. 27 years after the Chernobyl nuclear accident, the significant part of radionuclides deposited in peatland is still bioavailable. - Highlights: • Decrease of exchangeable 137 Cs and its increase in residual fraction with depth. • High 137 Cs transfer factor contrary to its low quantity in bioavailable fractions. • Fulvic/humic acids are a more effective carrier for Pu than for Cs

Biodegradation of buprofezin by Rhodococcus sp. strain YL-1 isolated from rice field soil.

Science.gov (United States)

Li, Chao; Zhang, Ji; Wu, Zhi-Guo; Cao, Li; Yan, Xin; Li, Shun-Peng

2012-03-14

A buprofezin-degrading bacterium, YL-1, was isolated from rice field soil. YL-1 was identified as Rhodococcus sp. on the basis of the comparative analysis of 16S rDNA sequences. The strain could use buprofezin as the sole source of carbon and nitrogen for growth and was able to degrade 92.4% of 50 mg L(-1) buprofezin within 48 h in liquid culture. During the degradation of buprofezin, four possible metabolites, 2-tert-butylimino-3-isopropyl-1,3,5-thiadiazinan-4-one, N-tert-butyl-thioformimidic acid formylaminomethyl ester, 2-isothiocyanato-2-methyl-propane, and 2-isothiocyanato-propane, were identified using gas chromatography-mass spectrometry (GC-MS) analysis. The catechol 2,3-dioxygenase activity was strongly induced during the degradation of buprofezin. A novel microbial biodegradation pathway for buprofezin was proposed on the basis of these metabolites. The inoculation of soils treated with buprofezin with strain YL-1 resulted in a higher degradation rate than that observed in noninoculated soils, indicating that strain YL-1 has the potential to be used in the bioremediation of buprofezin-contaminated environments.

{sup 137}Cs in northern Adriatic sediments

Energy Technology Data Exchange (ETDEWEB)

Barisic, D; Lulic, S; Vdovic, N; Vertacnik, A [Center for Marine Research - Department Zagreb, ' Ruder Boskovic' Institute, Zagreb (Croatia); Juracic, M [Department of Geology, Faculty of Natural Sciences, University of Zagreb, Zagreb (Croatia)

1996-01-01

The activity of {sup 137}Cs in shallow northern Adriatic sediments was obtained on the basis of measurement results from 25 sediment box cores, sampled during the Adriatic Scientific COoperation Program (ASCOP) 16 cruise in the summer 1990. {sup 137}Cs was determined in surface sediments (0-3 cm) and 12-15 cm-deep sediment. It was found that the lowest caesium concentrations correspond to sands, which are spread along the Croatian coast. Parallel to the Italian coast, {sup 137}Cs concentrations in pelites are the highest. It seems that the influence of Po River is significant for {sup 137}Cs activities in recent marine sediments along Italian coast south of Po River delta. Significantly higher {sup 137}Cs activities in 0-3 cm sediment layer can be attributed to the deposition caused by Chernobyl accident. (author)

Transfer of 137Cs to wild vegetables

International Nuclear Information System (INIS)

Ito, Nobuhiko; Natsuhori, Masahiro; Mezawa, Akane; Kawakami, Akira

1998-01-01

For the evaluation of internal radiation dose, it is needed to estimate the amount of radionuclide incorporated to human body using a simulation model. 137 Cesium (Cs) is easily transferred associating with food intake as well as potassium and so, Cs is an important nuclide for evaluation of internal radiation. 137 Cs concentrations in wild vegetables are higher than those of cultured vegetables and milk. Therefore, the transfer coefficients of 137 Cs from soil to wild vegetables were estimated in this study. Wild vegetables and soils of their farms were collected in the Hakkoda Mountain range of Aomori Prefecture. The levels of 137 Cs in wild vegetables were 0.42-18.35 (Bq/kg), whereas those in cabbage and spinach were 0.08 and 0.01 (Bq/kg), respectively, indicating that the Cs level is dozens to several hundreds times higher in wild vegetables than cultured ones. And the transfer coefficient was estimated as 0.003-0.94 for the former and 0.001-0.8 for the latter. On the other hand, 1 37 Cs levels of the soils on which wild vegetables grew was 28.0 Bq/kg and it was 3.9 Bq/kg for the farm soil. Furthermore, the effects of water content and pH of the soil on the transfer coefficient were studied. (M.N.)

Imbedded Nanocrystals of CsPbBr3 in Cs4 PbBr6 : Kinetics, Enhanced Oscillator Strength, and Application in Light-Emitting Diodes.

Science.gov (United States)

Xu, Junwei; Huang, Wenxiao; Li, Peiyun; Onken, Drew R; Dun, Chaochao; Guo, Yang; Ucer, Kamil B; Lu, Chang; Wang, Hongzhi; Geyer, Scott M; Williams, Richard T; Carroll, David L

2017-11-01

Solution-grown films of CsPbBr 3 nanocrystals imbedded in Cs 4 PbBr 6 are incorporated as the recombination layer in light-emitting diode (LED) structures. The kinetics at high carrier density of pure (extended) CsPbBr 3 and the nanoinclusion composite are measured and analyzed, indicating second-order kinetics in extended and mainly first-order kinetics in the confined CsPbBr 3 , respectively. Analysis of absorption strength of this all-perovskite, all-inorganic imbedded nanocrystal composite relative to pure CsPbBr 3 indicates enhanced oscillator strength consistent with earlier published attribution of the sub-nanosecond exciton radiative lifetime in nanoprecipitates of CsPbBr 3 in melt-grown CsBr host crystals and CsPbBr 3 evaporated films. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effect of growth media on cell envelope composition and nitrile hydratase stability in Rhodococcus rhodochrous strain DAP 96253.

Science.gov (United States)

Tucker, Trudy-Ann; Crow, Sidney A; Pierce, George E

2012-11-01

Rhodococcus is an important industrial microorganism that possesses diverse metabolic capabilities; it also has a cell envelope, composed of an outer layer of mycolic acids and glycolipids. Selected Rhodococcus species when induced are capable of transforming nitriles to the corresponding amide by the enzyme nitrile hydratase (NHase), and subsequently to the corresponding acid via an amidase. This nitrile biochemistry has generated interest in using the rhodococci as biocatalysts. It was hypothesized that altering sugars in the growth medium might impact cell envelope components and have effects on NHase. When the primary carbon source in growth media was changed from glucose to fructose, maltose, or maltodextrin, the NHase activity increased. Cells grown in the presence of maltose and maltodextrin showed the highest activities against propionitrile, 197 and 202 units/mg cdw, respectively. Stability of NHase was also affected as cells grown in the presence of maltose and maltodextrin retained more NHase activity at 55 °C (45 and 23 %, respectively) than cells grown in the presence of glucose or fructose (19 and 10 %, respectively). Supplementation of trehalose in the growth media resulted in increased NHase stability at 55 °C, as cells grown in the presence of glucose retained 40 % NHase activity as opposed to 19 % without the presence of trehalose. Changes in cell envelope components, such mycolic acids and glycolipids, were evaluated by high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC), respectively. Changing sugars and the addition of inducing components for NHase, such as cobalt and urea in growth media, resulted in changes in mycolic acid profiles. Mycolic acid content increased 5 times when cobalt and urea were added to media with glucose. Glycolipids levels were also affected by the changes in sugars and addition of inducing components. This research demonstrates that carbohydrate selection impacts NHase activity and

Enthalpy-increment measurements for CsI(s) and Cs2CrO4(s) by high-temperature Calvet calorimetry

International Nuclear Information System (INIS)

Venugopal, V.; Agarwal, R.; Roy, K.N.; Prasad, R.; Sood, D.D.

1987-01-01

Molar thermodynamic properties of CsI(s) and Cs 2 Cr O 4 (s) have been evaluated by enthalpy-increment measurements, using a Calvet high-temperature calorimeter. Least squares analyses were performed on the enthalpy increment results. Data is presented in tabular form for the dependence of enthalpy increments on temperature, in the range 333 to 822 K, for both caesium compounds, along with the thermal properties of the compounds. Good agreement is found between the present data and previously reported results on reduced enthalpy increments of CsI(s) and Cs 2 CrO 4 (s). (U.K.)

Transcriptional Response of Rhodococcus aetherivorans I24 to Polychlorinated Biphenyl-Contaminated Sediments

KAUST Repository

Puglisi, Edoardo

2010-04-06

We used a microarray targeting 3,524 genes to assess the transcriptional response of the actinomycete Rhodococcus aetherivorans I24 in minimal medium supplemented with various substrates (e. g., PCBs) and in both PCB-contaminated and non-contaminated sediment slurries. Relative to the reference condition (minimal medium supplemented with glucose), 408 genes were upregulated in the various treatments. In medium and in sediment, PCBs elicited the upregulation of a common set of 100 genes, including gene-encoding chaperones (groEL), a superoxide dismutase (sodA), alkyl hydroperoxide reductase protein C (ahpC), and a catalase/peroxidase (katG). Analysis of the R. aetherivorans I24 genome sequence identified orthologs of many of the genes in the canonical biphenyl pathway, but very few of these genes were upregulated in response to PCBs or biphenyl. This study is one of the first to use microarrays to assess the transcriptional response of a soil bacterium to a pollutant under conditions that more closely resemble the natural environment. Our results indicate that the transcriptional response of R. aetherivorans I24 to PCBs, in both medium and sediment, is primarily directed towards reducing oxidative stress, rather than catabolism. © 2010 Springer Science+Business Media, LLC.

Aerobic Biodegradation of N-Nitrosodimethylamine by the Propanotroph Rhodococcus ruber ENV425▿

Science.gov (United States)

Fournier, Diane; Hawari, Jalal; Halasz, Annamaria; Streger, Sheryl H.; McClay, Kevin R.; Masuda, Hisako; Hatzinger, Paul B.

2009-01-01

The propanotroph Rhodococcus ruber ENV425 was observed to rapidly biodegrade N-nitrosodimethylamine (NDMA) after growth on propane, tryptic soy broth, or glucose. The key degradation intermediates were methylamine, nitric oxide, nitrite, nitrate, and formate. Small quantities of formaldehyde and dimethylamine were also detected. A denitrosation reaction, initiated by hydrogen atom abstraction from one of the two methyl groups, is hypothesized to result in the formation of n-methylformaldimine and nitric oxide, the former of which decomposes in water to methylamine and formaldehyde and the latter of which is then oxidized further to nitrite and then nitrate. Although the strain mineralized more than 60% of the carbon in [14C]NDMA to 14CO2, growth of strain ENV425 on NDMA as a sole carbon and energy source could not be confirmed. The bacterium was capable of utilizing NDMA, as well as the degradation intermediates methylamine and nitrate, as sources of nitrogen during growth on propane. In addition, ENV425 reduced environmentally relevant microgram/liter concentrations of NDMA to <2 ng/liter in batch cultures, suggesting that the bacterium may have applications for groundwater remediation. PMID:19542346

Humoral immune responses of pregnant Guinea pigs Immunized with live attenuated Rhodococcus equi

Directory of Open Access Journals (Sweden)

Mawlood Abass Ali Al- Graibawi

2018-02-01

Full Text Available The potential to increase passive transfer of specific Rhodococcus equi (R.equi humoral immunity to newborn by preparturient vaccination of their dams was investigated in Pregnant Guinea pigs as a pilot study. Attenuated autogenous vaccine was prepared from a Congo red negative (CR- R.equi local isolate mixed with adjuvant (potassium alum sulphate, tested for sterility, safety and potency prior to vaccination .Two groups of pregnant G. pigs were used, the first group was vaccinated twice subcutaneously (S.C with the prepared vaccine at five and three weeks prior parturition, the second group was inoculated with adjuvant plus phosphate buffer saline (PBS twice s.c and kept as control. Offspring from the vaccinated dams had revealed high titers of specific R. equi antibody as detected by tube agglutination (TA and passive haemagglutination (PH test and showed protection against challenge dose. The results revealed that vaccination of pregnant G. pigs with the prepared attenuated vaccine was safe and efficient method to protect their offspring against experimental challenge with virulent R.equi. Vaccination was associated with increased humoral immune response in vaccinated group.

Uptake and release of {sup 134} Cs and {sup 137} Cs and iTs relation to {sup 40} K concentration in rats

Energy Technology Data Exchange (ETDEWEB)

Essa, M W.A.; Hussein, H H.M.; Abdelfattah, A T; Abdelbaky, W M [Nuclear research Center, Atomic Energy Authority, Cairo (Egypt)

1997-12-31

Studies were performed to examine the effect of a accumulation of {sup 134} Cs and Cs-137 on the concentration of K-40 in white rats. Five male and five female rats were fed with normal diet for four weeks. After that, the ten rats were fed with macaroni contaminated with Cs-134 (116 Bq/kg) and Cs-137 (318 Bq/kg) besides the normal diet. Animal whole body counting was done once weekly for four months using HPGe and multichannel analyzer. The results should that the uptake of cesium increases until saturation was reached after about one month to values 60,65 Bq/kg for Cs-134, and 200,240 Bq/kg for Cs-137. Results show a decrease in k-40 concentration due to the replacement of potassium ions by cesium ions in the cell. After saturation, feeding with radioactive diet was replaced by normal diet. A release of Cs-134 and Cs-137 was noticed with increase of K-40 concentration. 6 figs., 2 tabs.

The mobility of 137Cs and 90Sr in agricultural soils in the Ukraine, Belarus, and Russia, 1991

International Nuclear Information System (INIS)

Salbu, B.; Oughton, D.H.; Ratnikov, A.V.; Zhigareva, T.L.; Kruglov, S.V.; Petrov, K.V.; Grebenshakikova, N.V.; Firsakova, S.K.; Astasheva, N.P.; Loshchilov, N.A.

1994-01-01

Results are presented from studies concerning the behavior of the Chernobyl-derived radionuclides 137 Cs and 90 Sr in soil-plant agricultural systems in the Ukraine, Belarus, and Russia during 1991. The sites, representing ploughed and natural pastures, were located at varying distances between 50 and 650 km and varying directions from the Chernobyl reactor site. The 137 Cs activity concentrations in the upper 0-5 cm soil layer ranged from 25-1,000 kBq m -2 and were higher in natural pastures as compared to ploughed pastures. For 90 Sr, activity levels ranged from 1.4-40 kBq m -2 , and the highest 90 Sr deposition was observed in the Gomel Region, Belarus. The highest 90 Sr: 137 Cs ratio was also observed in the Gomel soils, i.e., 15% as compared to between 0.72 and 7.4% in the other soils. The mobility of radionuclides was studied by means of sequential extraction. For all soils, between 60 and 95% of the 137 Cs was found to be strongly bound to soil components. In the Russian and Ukrainian soils, between 40 and 98% of the 90 Sr was found in the easily extractable fractions, and the distribution of 137 Cs and 90 Sr followed that of the naturally occurring stable isotopes of cesium and strontium. However, in the Gomel soils, between 20 and 50% of the 90 Sr was easily extractable and the distribution of 90 Sr within the extraction fractions did not follow that observed for stable strontium. These results are though to reflect the association of 90 Sr with fuel particles deposited in the Gomel Region. The mobility of 90 Sr is expected to increase with time (as the particles weather) in these soils. 24 refs., 14 figs., 3 tabs

Solution-Grown CsPbBr3 /Cs4 PbBr6 Perovskite Nanocomposites: Toward Temperature-Insensitive Optical Gain.

Science.gov (United States)

Wang, Yue; Yu, Dejian; Wang, Zeng; Li, Xiaoming; Chen, Xiaoxuan; Nalla, Venkatram; Zeng, Haibo; Sun, Handong

2017-09-01

With regards to developing miniaturized coherent light sources, the temperature-insensitivity in gain spectrum and threshold is highly desirable. Quantum dots (QDs) are predicted to possess a temperature-insensitive threshold by virtue of the separated electronic states; however, it is never observed in colloidal QDs due to the poor thermal stability. Besides, for the classical II-VI QDs, the gain profile generally redshifts with increasing temperature, plaguing the device chromaticity. Herein, this paper addresses the above two issues simultaneously by embedding ligands-free CsPbBr 3 nanocrystals in a wider band gap Cs 4 PbBr 6 matrix by solution-phase synthesis. The unique electronic structures of CsPbBr 3 nanocrystals enable temperature-insensitive gain spectrum while the lack of ligands and protection from Cs 4 PbBr 6 matrix ensure the thermal stability and high temperature operation. Specifically, a color drift-free stimulated emission irrespective of temperature change (20-150 °C) upon two-photon pumping is presented and the characteristic temperature is determined to be as high as ≈260 K. The superior gain properties of the CsPbBr 3 /Cs 4 PbBr 6 perovskite nanocomposites are directly validated by a vertical cavity surface emitting laser operating at temperature as high as 100 °C. The results shed light on manipulating optical gain from the advantageous CsPbBr 3 nanocrystals and represent a significant step toward the temperature-insensitive frequency-upconverted lasers. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cs-137 migration in soil near NPPs

International Nuclear Information System (INIS)

Silant'ev, A.N.; Shkuratova, I.G.; Khatskevich, R.N.

1984-01-01

A convective-diffusion model has been employed for describing Cs-137 migration in soil. The migration parameters were determined by comparing the calculated vertical distribution profiles with the experimental ones. The migration parameters dependence on the soil state has been studied. Cs-137 penetration rate was found to be function of the soil type, surface state, soil wetness and orography. The obtained values are presented. A method is suggested for revealing the soil surface contamination by Cs-137 produced during NPP operation with distinguishing it from the global contamination background. For this purpose Cs-137 content in the upper 5 mm soil layer is estimated [ru

Is 137Cs Dating Becoming Obsolete in North America?

Science.gov (United States)

Drexler, J. Z.; Fuller, C.; Salas, A.

2016-12-01

Dating of wetland sediments and peat is routinely carried out using 137Cs and 210Pb analysis. Unlike 210Pb, 137Cs is an anthropogenic radionuclide with a history of fallout from nuclear weapons testing. 137Cs is used as a single time marker; its peak is coincident with the height of atmospheric nuclear testing in 1963/4. During its use in the 1970s-90s, 137Cs peaks were usually highly distinct in wetland sediments (e.g., see 137Cs peaks from Louisiana marshes in Feijtel et al., 1988). This enabled its use as a check for dates assigned to a profile by 210Pb and other methods. However, recently, the efficacy of 137Cs dating in North America has deteriorated. In this presentation, we will provide specific examples of 137Cs as well as 210Pb dating in wetland sediments/peats we collected between 2005 and 2015 in Maine, California, Virginia, North Carolina, South Carolina, and Washington. Two main reasons exist for this decline. First, 137Cs activities in our recent cores are 30-40 % of the original activities in 1963/4 due to decay of the original 137Cs in situ (half-life = 30.17 years) and no major new sources. This manifests in lower signal to noise ratio, with some peaks barely recognizable above the noise. Second, 137Cs peaks are much less distinct due to 137Cs migration through time independent of substrate (or sediment) particles. Migration of peaks has resulted in estimated accretion rates being systematically lower or higher than those derived from 210Pb dating. These issues with 137Cs dating have important implications because 137Cs is used with 210Pb dating or even alone to determine rates of recent wetland carbon accumulation. Such rates are required to enter wetland restoration projects into carbon markets and to document IPCC mandated reductions in carbon pollution. Our analysis shows that, although dating by 137Cs alone has always been highly tenuous, now it is especially contraindicated and should be disallowed for the purposes of carbon accounting.

Dimetilsulfóxido - DMSO no teste de sensibilidade microbiana in vitro em cepas de Rhodococcus equi isoladas de afecções pulmonares em potros

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Ribeiro Márcio Garcia

2001-01-01

Full Text Available Comparou-se a sensibilidade microbiana in vitro de isolados de Rhodococcus equi pelo teste padrão de difusão com discos, com o modificado, pela adição de 5% de dimetilsulfóxido-DMSO. Observou-se aumento da sensibilidade do R. equi no teste com DMSO, frente a aminoglicosídeos (canamicina, amicacina, estreptomicina e ao cloranfenicol, enquanto para a eritromicina e derivados ß-lactâmicos (penicilina G, cefalosporinas, amoxicilina, oxacilina, constatou-se redução da sensibilidade do agente.

An optical microscopy study of the swelling of wet-spun films of CsDNA as a function of hydration and CsCl concentration

Science.gov (United States)

Schwenker, Megan; Marlowe, Robert; Lee, Scott; Rupprecht, Allan

2005-03-01

Highly oriented, wet-spun films of DNA expand in the direction perpendicular to the helical axis as the hydration of the film is increased. CsDNA films with a high CsCl content show an unexpected shrinkage at a relative humidity of 92%. Our most recent experiments have been to measure the perpendicular dimension of CsDNA as a function of both hydration and concentration of CsCl. Our preliminary results show that no shrinkage is observed at low contents of CsCl, showing that the CsCl plays an integral role in the shrinkage phenomenon.

137Cs in the western South Pacific Ocean

International Nuclear Information System (INIS)

Yamada, Masatoshi; Wang Zhongliang

2007-01-01

The 137 Cs activities were determined for seawater samples from the East Caroline, Coral Sea, New Hebrides, South Fiji and Tasman Sea (two stations) Basins of the western South Pacific Ocean by γ spectrometry using a low background Ge detector. The 137 Cs activities ranged from 1.4 to 2.3 Bq m -3 over the depth interval 0-250 m and decreased exponentially from the subsurface to 1000 m depth. The distribution profiles of 137 Cs activity at these six western South Pacific Ocean stations did not differ from each other significantly. There was a remarkable difference for the vertical profiles of 137 Cs activity between the East Caroline Basin station in this study and the GEOSECS (Geochemical Ocean Sections Study) station at the same latitude in the Equatorial Pacific Ocean; the 137 Cs inventory over the depth interval 100-1000 m increased from 400 ± 30 Bq m -2 to 560 ± 30 Bq m -2 during the period from 1973 to 1992. The total 137 Cs inventories in the western South Pacific Ocean ranged from 850 ± 70 Bq m -2 in the Coral Sea Basin to 1270 ± 90 Bq m -2 in the South Fiji Basin. Higher 137 Cs inventories were observed at middle latitude stations in the subtropical gyre than at low latitude stations. The 137 Cs inventories were 1.9-4.5 times (2.9 ± 0.7 on average) and 1.7-4.3 times (3.1 ± 0.7 on average) higher than that of the expected deposition density of atmospheric global fallout at the same latitude and that of the estimated 137 Cs deposition density in 10 o latitude by 10 deg. longitude grid data obtained by Aoyama et al. [Aoyama M, Hirose K, Igarashi Y. Re-construction and updating our understanding on the global weapons tests 137 Cs fallout. J Environ Monit 2006;8:431-438], respectively. The possible processes for higher 137 Cs inventories in the western South Pacific Ocean than that of the expected deposition density of atmospheric global fallout may be attributable to the inter-hemisphere dispersion of the atmospheric nuclear weapons testing 137 Cs from

Measurement of 137Cs activity in living chicken

International Nuclear Information System (INIS)

Balas, J.; Poeschl, M.

1998-01-01

The possibility of measuring the 137 Cs activity in broiler chickens in vivo was examined. The experiment was conducted with broiler chickens 7 to 22 days old (White Leghorn hybrid, race ISA VEDETTE). Three oral doses of 137 Cs (total activity 5 kBq/chicken) were administered during a day (at 8:00, 12:00 and 16:00). The radioactivity was determined by gamma spectroscopy with a stabilised Nal/Tl detector. The measurement was carried out on days 1, 2, 3, 4, 7, 8, 14 and 15 after the 137 Cs administration in vivo. The detector was put closely to the body in the area of breast muscles. The radiocesium activity concentrations in fresh daily excreta were also determined. A rapid uptake of the orally administered 137 Cs (within a few hours) as well as a rapid loss of radiocesium were observed. The dynamics and accuracy of the in vivo measurement of 137 Cs activity were comparable with the recently published results of in vitro measurement of radiocesium activity. Only the initial 137 Cs activity (during 2 days after 137 Cs application) was higher with regard to the content of contaminated feed mixture in the gastrointestinal tract

A simple preparation of calibration curve standards of 134Cs and 137Cs by serial dilution of a standard reference material

International Nuclear Information System (INIS)

Labrecque, J.J.; Rosales, P.A.

1990-01-01

Two sets of calibration standards for 134 Cs and 137 Cs were prepared by small serial dilution of a natural matrix standard reference material, IAEA-154 whey powder. The first set was intended to screen imported milk powders which were suspected to be contaminated with 134 Cs and 137 Cs. Their concentration ranged from 40 to 400 Bq/kg. The other set of calibration standards was prepared to measure the environmental levels of 137 Cs in commercial Venezuelan milk powders. Their concentration ranged from 3 to 10 Bq/kg of 137 Cs. The accuracy of these calibration curves was checked by IAEA-152 and A-14 milk powders. Their measured values were in good agreement with their certified values. Finally, it is shown that these preparation techniques using serial dilution of a standard reference material were simple, rapid, precise, accurate and cost-effective. (author) 5 refs.; 5 figs.; 3 tabs

Nitrile hydratase of Rhodococcus erythropolis: characterization of the enzyme and the use of whole cells for biotransformation of nitriles.

Science.gov (United States)

Kamble, Ashwini L; Banoth, Linga; Meena, Vachan Singh; Singh, Amit; Chisti, Yusuf; Banerjee, U C

2013-08-01

The intracellular cobalt-type nitrile hydratase was purified from the bacterium Rhodococcuserythropolis. The pure enzyme consisted of two subunits of 29 and 30 kDa. The molecular weight of the native enzyme was estimated to be 65 kDa. At 25 °C the enzyme had a half-life of 25 h. The Michaelis-Menten constants K m and v max for the enzyme were 0.624 mM and 5.12 μmol/min/mg, respectively, using 3-cyanopyridine as the substrate. The enzyme-containing freely-suspended bacterial cells and the cells immobilized within alginate beads were evaluated for converting the various nitriles to amides. In a packed bed reactor, alginate beads (2 % alginate; 3 mm bead diameter) containing 200 mg/mL of cells, achieved a conversion of >90 % for benzonitrile and 4-cyanopyridine in 38 h (25 °C, pH 7.0) at a feed substrate concentration of 100 mM. The beads could be reused for up to six reaction cycles.

Increase in Bacterial Colony Formation from a Permafrost Ice Wedge Dosed with a Tomitella biformata Recombinant Resuscitation-Promoting Factor Protein.

Science.gov (United States)

Puspita, Indun Dewi; Kitagawa, Wataru; Kamagata, Yoichi; Tanaka, Michiko; Nakatsu, Cindy H

2015-01-01

Resuscitation-promoting factor (Rpf) is a protein that has been found in a number of different Actinobacteria species and has been shown to promote the growth of active cells and resuscitate dormant (non-dividing) cells. We previously reported the biological activity of an Rpf protein in Tomitella biformata AHU 1821(T), an Actinobacteria isolated from a permafrost ice wedge. This protein is excreted outside the cell; however, few studies have investigated its contribution in environmental samples to the growth or resuscitation of bacteria other than the original host. Therefore, the aim of the present study was to determine whether Rpf from T. biformata impacted the cultivation of other bacteria from the permafrost ice wedge from which it was originally isolated. All experiments used recombinant Rpf proteins produced using a Rhodococcus erythropolis expression system. Dilutions of melted surface sterilized ice wedge samples mixed with different doses of the purified recombinant Rpf (rRpf) protein indicated that the highest concentration tested, 1250 pM, had a significantly (p permafrost sediments. The results of the present study demonstrated that rRpf not only promoted the growth of T. biformata from which it was isolated, but also enhanced colony formation by another Actinobacteria in an environmental sample.

Increasing the production of desulfurizing biocatalysts by means of fed - batch culture

International Nuclear Information System (INIS)

Berdugo, C I; Mena, J A; Acero, J R; Mogollon, L

2001-01-01

Over the past years, environmental regulations have driven a lot of effort for the development of new technologies for the upgrading of fossil fuels. Biotechnology offers an alternative way to process fossil fuels by means of a biodesulfurization technology where the production of the biocatalyst is one of the key topics. Traditionally, the production is carried out in batch culture where the maximum cellular concentration is restricted by inherent limitations of the culture type and the microorganism growth rate. This work addresses the production of two desulfurizing microorganisms: Rhodococcus erythropolis IGTS8 and gordona rubropertinctus ICP172 using fed-batch culture. Fed-batch cultures were conducted in a 12 L fermentor using ICP 4 medium containing glucose and DMSO as carbon and sulfur sources. As a result, cell concentration was increased 1.5 and 3 times with fed-batch cultures using constant and exponential flow respectively, achieving a maximum cell concentration of 7.3 g DCW/L of biocatalyst igts8 and 12.85 gGDCW/L of the new biocatalyst ICP172. Both biocatalysts presented biodesulfurization activity in a spiked matrix DBT/HXD and in diesel matrix with the detection of 2-HBP which is the end-product of DBT degradation pathway

Molecular characterization of Rhodococcus equi isolates from horses in Poland: pVapA characteristics and plasmid new variant, 85-kb type V.

Science.gov (United States)

Witkowski, Lucjan; Rzewuska, Magdalena; Takai, Shinji; Chrobak-Chmiel, Dorota; Kizerwetter-Świda, Magdalena; Feret, Małgorzata; Gawryś, Marta; Witkowski, Maciej; Kita, Jerzy

2017-01-26

Rhodococcus equi is one of the most significant bacterial pathogens affecting foals up to 6 months of age worldwide. Rhodococcosis is present in Poland however information about molecular characterization of R. equi isolates is scarce. This study describes molecular characterization of Rhodococcus equi infection on 13 horse breeding farms in Poland between 2001 and 2012. Samples were collected by tracheobronchial aspiration from pneumonic foals or during necropsy. The R. equi isolates were genotyped by plasmid profiling and pulsed-field gel electrophoresis. Totally, 58 R. equi isolates were investigated. One isolate lost its plasmid. Among the 57 VapA-positive isolates, 48 contained 85-kb type I plasmid (82.8%), 8 contained 87-kb type I plasmid (13.8%). One isolate (1.7%) had a unique restriction cleavage pattern and the 2nd fragment of EcoRI digests of this plasmid DNA was about 2600 bases smaller than that of the 85 kb type I. This new plasmid variant was designated as the "85-kb type V". Among the 58 isolates typeable with VspI-PFGE, ten PFGE clusters were detected. The majority of foals were infected mostly with isolates of low genetic diversity. Most of clinical isolates of R. equi from foals in Poland contain pVapA 85-kb type I and 87-kb type I similarly to the other European countries and the United States. However, the new variant of pVapA 85-kb type V was identified. The chromosomal variability was detected among some of the investigated isolates and the presence of farm-specific isolates might be possible.

Bioremediation of soil contaminated by dichlorodiphenyltrichloroethane with the use of aerobic strain Rhodococcus wratislaviensis Ch628

Science.gov (United States)

Egorova, D. O.; Farafonova, V. V.; Shestakova, E. A.; Andreyev, D. N.; Maksimov, A. S.; Vasyanin, A. N.; Buzmakov, S. A.; Plotnikova, E. G.

2017-10-01

The concentration of dichlorodiphenyltrichloroethane (DDT) was determined in a sandy soil of specially Protected Natural Area Osinskaya Lesnaya Dacha (Perm region) 45 years after the last application of the insecticide in this area. The concentration of DDT in the soil exceeded the maximum permissible concentration by 250 times and reached 25.05 mg/kg of soil. Under the conditions of model experiment, efficient decontamination of the soil was recorded in the system with the introduced strain Rhodococcus wratislaviensis Ch628; the DDT concentration decreased by 99.7% and equaled 0.07 mg/kg. The process of DDT degradation proceeded slower in the model soil system with autochthonous microbial complex. In this case, 58.2% DDT degraded in 70 days, and the final concentration was 10.47 mg/kg. The soil lost its toxicity for animal and plant test objects by the end of the experiment only in the model system containing the R. wratislaviensis Ch628 strain.

Fractionation of (137)Cs and Pu in natural peatland.

Science.gov (United States)

Mihalík, Ján; Bartusková, Miluše; Hölgye, Zoltán; Ježková, Tereza; Henych, Ondřej

2014-08-01

High Cs-137 concentrations in plants growing on peatland inspired us to investigate the quantity of its bioavailable fraction in natural peat. Our investigation aims to: a) estimate the quantity of bioavailable Cs-137 and Pu present in peat, b) verify the similarity of Cs-137 and K-40 behaviours, and c) perform a quantification of Cs-137 and Pu transfer from peat to plants. We analysed the vertical distribution of Cs-137 and Pu isotopes in the peat and their concentrations in plants growing on these places. Bioavailability of radionuclides was investigated by sequential extraction. Sequential analyses revealed that it was the upper layer which contained the majority of Cs-137 in an available form while deeper layers retained Cs-137 in immobile fractions. We can conclude that 18% of all Cs-137 in the peat is still bioavailable. Despite of the low quantity of bioavailable fraction of Cs-137 its transfer factor reached extremely high values. In the case of Pu, 64% of its total amount was associated with fulvic/humic acids which resulted in the high transfer factor from peat to plants. 27 years after the Chernobyl nuclear accident, the significant part of radionuclides deposited in peatland is still bioavailable. Copyright © 2014 Elsevier Ltd. All rights reserved.

Energy- and temperature dependences of secondary electron emission of CsI- and CsBr layers doped with Cd

International Nuclear Information System (INIS)

Galij, P.V.; Tsal', N.A.

1983-01-01

The energy and temperature dependences of the secondary electron emission coefficient (SEEC) of CsI-Cd-, CsBr-Cd-, CsI-CsBr layers have been studied. The effect of bivalent cadmium impurity on the SEEC value is investigated. It is shown that implantation of small amounts of Cd 2+ impurity into the lattice of the initial monocrystals might increase the SEEC values of the layers. Temperature dependences (TD) of SEEC are measured and the possibility of comparing experimental results with the Dekker formula is analyzed. A conclusion is drawn that the Dekker model well describes the TD of SEEC of doped layers at temperatures T < or approximately 100 deg C. At elevated temperatures., along with secondary electron scattering on phonons, one should take into account their scattering on vacancies

Cs0.49NbPS6

Directory of Open Access Journals (Sweden)

Hoseop Yun

2011-01-01

Full Text Available The quaternary thiophosphate, Cs0.49NbPS6, caesium hexathioniobiophosphate(V, has been synthesized by the reactive halide flux method. The title compound is isotypic with Rb0.46TaPS6 and is made up of a bicapped trigonal–biprismatic [Nb2S12] unit and a tetrahedral [PS4] group. The [Nb2S12] units linked by the [PS4] tetrahedra form infinite chains, yielding a three-dimensional network with rather large van der Waals gaps along the c axis in which the disordered Cs+ ions reside. The electrons released by the Cs atoms are transferred to the pairwise niobium metal site and there are substantial intermetallic Nb—Nb bonding interactions. This leads to a significant decrease of the intermetallic distance in the title compound compared to that in TaPS6. The classical charge balance of the title compound may be represented as [Cs+]0.49[Nb4.51+][P5+][S2−]4[S22−].

Uptake and distribution of 137Cs and stable Cs by microorganisms isolated from mushroom substrata in the Japanese forests

International Nuclear Information System (INIS)

Kuwahara, Chikako; Fukumoto, Atsushi; Kato, Fumio; Sugiyama, Hideo

2004-01-01

The pH values of wild mushroom substrata, the influence of pH in medium on the appearance frequencies of microorganisms from mushroom substrata, and growth and Cs uptake by several microorganisms were investigated. The results showed that the pH values of 42 mushroom substrata were slightly acidic. There was no remarkable difference in the appearance frequencies of filamentous actinomycetes and planktonic bacteria at pH 5, 6 and 7, except in the samples of mushroom substrata from Mt. Fuji. The values of Cs concentration ratio (CR) for microorganisms isolated from mushroom substrata and for mushrooms were almost the same level, suggesting that those microorganisms could take up Cs in substrata and reserve Cs in their cells. (author)

Cs[FeSe{sub 2}], Cs{sub 3}[FeSe{sub 2}]{sub 2}, and Cs{sub 7}[Fe{sub 4}Se{sub 8}]. Missing links of known chalcogenido ferrate series

Energy Technology Data Exchange (ETDEWEB)

Stueble, Pirmin; Roehr, Caroline [Institut fuer Anorganische und Analytische Chemie, Universitaet Freiburg (Germany)

2017-11-17

The three cesium selenido ferrate title compounds with an Se:Fe ratio of 2:1 were synthesized from stoichiometric samples reacting elemental Cs either (A) with Fe and Se in a double-crucible setup (Cs[FeSe{sub 2}], Cs{sub 3}[FeSe{sub 2}]{sub 2}) or (B) with previously prepared FeSe{sub 2} (Cs{sub 3}[FeSe{sub 2}]{sub 2}, Cs{sub 7}[Fe{sub 4}S{sub 8}]) (T{sub max} = 800-1000 C). The pure Fe{sup III} ferrate Cs[FeSe{sub 2}] crystallizes in the Tl[FeSe{sub 2}] type [monoclinic, space group C2/m, a = 1392.95(10), b = 564.43(3), c = 737.44(6) pm, β = 119.163(5) , Z = 4, R{sub 1} = 0.0550]. It is thus not isotypic to all other alkali ferrates(III) A[FeS{sub 2}] and A[FeSe{sub 2}] containing chains of edge-sharing tetrahedra, but crystallizes in a t2 subgroup of the Immm structure of Cs[FeS{sub 2}]. The mixed-valent chain compound Cs{sub 3}[FeSe{sub 2}]{sub 2} is isotypic to its sulfido analogue [orthorhombic, space group Pnma, a = 777.88(6), b = 1151.02(6), c = 1341.61(7) pm, Z = 4, R{sub 1} = 0.0470]. In contrast to the isopunctal Na{sub 3}[FeSe{sub 2}]{sub 2} type K/Rb compounds the chains are only slightly corrugated. The monoclinic, likewise mixed-valent Fe{sup II/III} selenido ferrate Cs{sub 7}[Fe{sub 4}Se{sub 8}] [monoclinic, space group C2/c, a = 1953.79(10), b = 879.71(5), c = 1717.03(10) pm, β = 117.890(2) , Z = 4, R{sub 1} = 0.0816] is isostructural both to the cesium sulfido and tellurido compound. The structure contains oligomeric moieties of four edge sharing [FeSe{sub 4}] tetrahedra forming slightly distorted tetrahedral clusters [Fe{sub 4}Se{sub 8}]{sup 7-}, which are surrounded by a cube of 26 Cs cations. Based on a structure map, the crystal chemistry of the three title compounds is discussed together with all chain/cluster ferrates of the general series A{sub 1+x}[Fe{sup III}{sub 1-x}Fe{sup II}{sub x}Q{sub 2}] (x = 0-1; A = Na, K, Rb, Cs; Q = S, Se, Te). (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Learning Flash CS4 Professional

CERN Document Server

Shupe, Rich

2009-01-01

Learning Flash CS4 Professional offers beginners and intermediate Flash developers a unique introduction to the latest version of Adobe's powerful multimedia application. This easy-to-read book is loaded with full-color examples and hands-on tasks to help you master Flash CS4's new motion editor, integrated 3D system, and character control using the new inverse kinematics bones animation system. No previous Flash experience is necessary.

The Two Translationally Controlled Tumor Protein Genes, CsTCTP1 and CsTCTP2, Are Negative Modulators in the Cucumis sativus Defense Response to Sphaerotheca fuliginea

Directory of Open Access Journals (Sweden)

Xiangnan Meng

2018-04-01

Full Text Available Pathogen stress often significantly decreases cucumber production. However, knowledge regarding the molecular mechanism and signals of cucumber disease resistance is far from complete. Here, we report two translationally controlled tumor protein genes, CsTCTP1 and CsTCTP2, that are both negative modulators in the Cucumis sativus defense response to Sphaerotheca fuliginea. Subcellular localization analysis showed that CsTCTP1 and CsTCTP2 were both localized in the cytoplasm. Expression analysis indicated that the transcript levels of CsTCTP1 and CsTCTP2 were linked to the degree of cucumber resistance to S. fuliginea. Transient overexpression of either CsTCTP1 or CsTCTP2 in cucumber cotyledons impaired resistance to S. fuliginea, whereas silencing of either CsTCTP1 or CsTCTP2 enhanced cucumber resistance to S. fuliginea. The relationship of several defense-related genes and ABA and target of rapamycin (TOR signaling pathway-related genes to the overexpressing and silencing of CsTCTP1/CsTCTP2 in non-infested cucumber plants was investigated. The results indicated that CsTCTP1 participates in the defense response to S. fuliginea by regulating the expression of certain defense-associated genes and/or ABA signaling pathway-associated genes, and CsTCTP2 participates through regulating the expression of TOR signaling pathway-associated genes. Our findings will guide enhancing the resistance of cucumber to powdery mildew.

Coprecipitation of 137Cs and 85Sr microquantities with complex compound [M(18-crown-6)]BPH4 (M=Na+, Cs+) from neutral and alkaline solutions

International Nuclear Information System (INIS)

Konovalova, N.A.; Rumer, I.A.; Kulyukhin, S.A.

2009-01-01

The paper reports the possibility of joint separation of 137 Cs and 85 Sr from neutral and alkaline aqueous solutions by their coprecipitation with the solid phase of complex compounds [M(18-crown-6)]BPh 4 (M=Na + , Cs + ), as well as to study the coprecipitation of 137 Cs and 85 Sr with the solid phase CsBPh 4 . It is found that complex compounds [M(18-crown-6)]BPh 4 (M=Na + , Cs + ) increased the degree of 85 Sr separation from solutions virtually two- to threefold vs. CsBPh 4 . Chloride and nitrate were found to have hardly any impact on the coprecipitation of 137 Cs and 85 Sr with [M(18-crown-6)]BPh 4 (M = Na + , Cs + ). (orig.)

Bygningers varmebehov 98, Bv98

DEFF Research Database (Denmark)

Bygningers energibehov og i SBI-anvisning 189 Småhuse. Programmet kan anvendes på pc under operativsystemet Microsoft Windows 95, Windows 98 og Windows NT 4.0, Servicepack 3 eller nyere. Pc-programmet er en revideret og moderniseret udgave af pc-programmet Bygningers Varmebehov, BV95, som SBI udgav i 1995....

Mobility and plant availability of radioactive Cs in natural soil in relation to stable Cs, other alkali elements and soil fertility

International Nuclear Information System (INIS)

Varskog, P.; Steinnes, E.; Naeumann, R.

1994-01-01

The mobility and plant availability of radioactive Cs from the Chernobyl accident in natural soil-plant systems of varying fertility were studied at three sampling locations situated in subalpine areas of central Norway. The soil samples included litter, humus (0-2 cm and 2-5 cm depth), and mineral soil (8-12 cm and 20-30 cm depth), and the plant species studied were Betula nana, Empetrum hermaphroditum and Juncus trifidus. The lichen Cetraria nivalis was also sampled. The sampling took place in the middle of the growth season during the period 1987-1989. The soil and vegetation samples were analysed with respect to total radiocaesium ( 137 Cs and 134 Cs), Rb, stable Cs and exchangeable 137 Cs (in soil only), K, Ca and Mg. (Author)

Effect of nutrition peculiarities on 137Cs uptake

International Nuclear Information System (INIS)

Knizhnikov, V.A.; Marej, A.N.; Borisov, B.K.; Petukhova, Eh.V.

1980-01-01

Reasons for different 137 Cs uptake from diets of the vegetable-animal type are studied. Indexes of accumulation multiplicity for Moscow and the Byelorussian-Ukrainian wooded district are compared. 137 Cs buildup levels in the organism of the USSR and the USA population are presented. The most probable reason for peculiarities in 137 Cs uptake from various types of diet, as well as the reason for the alterations in the uptake of this radionuclide from the diet of the same type, is the non-uniformity of 137 Cs contribution of aerial and nonaerial origin

CsMYB5a and CsMYB5e from Camellia sinensis differentially regulate anthocyanin and proanthocyanidin biosynthesis.

Science.gov (United States)

Jiang, Xiaolan; Huang, Keyi; Zheng, Guangshun; Hou, Hua; Wang, Peiqiang; Jiang, Han; Zhao, Xuecheng; Li, Mingzhuo; Zhang, Shuxiang; Liu, Yajun; Gao, Liping; Zhao, Lei; Xia, Tao

2018-05-01

Tea is one of the most widely consumed nonalcoholic beverages worldwide. Polyphenols are nutritional compounds present in the leaves of tea plants. Although numerous genes are functionally characterized to encode enzymes that catalyze the formation of diverse polyphenolic metabolites, transcriptional regulation of those different pathways such as late steps of the proanthcoyanidin (PA) pathway remains unclear. In this study, using different tea transcriptome databases, we screened at least 140 R2R3-MYB transcription factors (TFs) and grouped them according to the basic function domains of the R2R3 MYB TF superfamily. Among 140 R2R3 TFs, CsMYB5a and CsMYB5e were chosen for analysis because they may be involved in PA biosynthesis regulation. CsMYB5a-overexpressing tobacco plants exhibited downregulated anthocyanin accumulation but a high polymeric PA content in the flowers. Overexpression of CsMYB5e in tobacco plants did not change the anthocyanin content but increased the dimethylaminocinnamaldehyde-stained PA content. RNA-seq and qRT-PCR analyses revealed that genes related to PA and anthocyanin biosynthesis pathways were markedly upregulated in both CsMYB5a- and CsMYB5e-overexpressing flowers. Three UGTs and four GSTs were identified as involved in PA and anthocyanin glycosylation and transportation in transgenic plants. These results provide new insights into the regulation of PA and anthocyanin biosynthesis in Camellia sinensis. Copyright © 2018 Elsevier B.V. All rights reserved.

Recovery of Cs from high level radioactive waste

International Nuclear Information System (INIS)

Kumar, Amar; Kaushik, C.P.; Raj, K.; Varshney, Lalit

2008-01-01

Separation of Cs + from HLW restricts the personal radiation exposure during the vitrification and prevents thermal deformation of conditioned waste matrix during storage because of the high calorific power of 134 Cs (13.18 W/g) and 137 Cs (0.417 W/g) which would markedly reduce the storage cost. Separation will also reduce its volatility during vitrification and extent of migration from the vitrified mass in repository. In addition 137 Cs has enormous applications as radiation sources in food preservation, sterilization of medical products, brachy therapy, blood irradiation, hygienization of sewage sludge etc. The use of 137 Cs (T 1/2 = 30 years) in place of 60 Co (T 1/2 = 5.2 years) will also reduce the shielding requirement and frequency of source replenishment which will ease the handling/transportation of radioactive source

The sensor kinase MprB is required for Rhodococcus equi virulence.

Science.gov (United States)

MacArthur, Iain; Parreira, Valeria R; Lepp, Dion; Mutharia, Lucy M; Vazquez-Boland, José A; Prescott, John F

2011-01-10

Rhodococcus equi is a soil bacterium and, like Mycobacterium tuberculosis, a member of the mycolata. Through possession of a virulence plasmid, it has the ability to infect the alveolar macrophages of foals, resulting in pyogranulomatous bronchopneumonia. The virulence plasmid has an orphan two-component system (TCS) regulatory gene, orf8, mutation of which completely attenuates virulence. This study attempted to find the cognate sensor kinase (SK) of orf8. Annotation of the R. equi strain 103 genome identified 23 TCSs encoded on the chromosome, which were used in a DNA microarray to compare TCS gene transcription in murine macrophage-like cells to growth in vitro. This identified six SKs as significantly up-regulated during growth in macrophages. Mutants of these SKs were constructed and their ability to persist in macrophages was determined with one SK, MprB, found to be required for intracellular survival. The attenuation of the mprB- mutant, and its complementation, was confirmed in a mouse virulence assay. In silico analysis of the R. equi genome sequence identified an MprA binding box motif homologous to that of M. tuberculosis, on mprA, pepD, sigB and sigE. The results of this study also show that R. equi responds to the macrophage environment differently from M. tuberculosis. MprB is the first SK identified as required for R. equi virulence and intracellular survival. Copyright © 2010 Elsevier B.V. All rights reserved.

Bacterial CS2 Hydrolases from Acidithiobacillus thiooxidans Strains Are Homologous to the Archaeal Catenane CS2 Hydrolase

NARCIS (Netherlands)

Smeulders, M.J.; Pol, A. van der; Venselaar, H.; Barends, T.R.; Hermans, J.; Jetten, M.S.M.; Camp, H.J.M. op den

2013-01-01

Carbon disulfide (CS2) and carbonyl sulfide (COS) are important in the global sulfur cycle, and CS2 is used as a solvent in the viscose industry. These compounds can be converted by sulfur-oxidizing bacteria, such as Acidithiobacillus thiooxidans species, to carbon dioxide (CO2) and hydrogen sulfide

Differences in Rhodococcus equi Infections Based on Immune Status and Antibiotic Susceptibility of Clinical Isolates in a Case Series of 12 Patients and Cases in the Literature

Science.gov (United States)

Suzuki, Yasuhiro; Ribes, Julie A.; Thornton, Alice

2016-01-01

Rhodococcus equi is an unusual zoonotic pathogen that can cause life-threatening diseases in susceptible hosts. Twelve patients with R. equi infection in Kentucky were compared to 137 cases reported in the literature. Although lungs were the primary sites of infection in immunocompromised patients, extrapulmonary involvement only was more common in immunocompetent patients (P antibiotics, preferably selected from vancomycin, imipenem, clarithromycin/azithromycin, ciprofloxacin, rifampin, or cotrimoxazole. Local antibiograms should be checked prior to using cotrimoxazole due to developing resistance. PMID:27631004

Early stages of Cs adsorption mechanism for GaAs nanowire surface

Science.gov (United States)

Diao, Yu; Liu, Lei; Xia, Sihao; Feng, Shu

2018-03-01

In this study, the adsorption mechanism of Cs adatoms on the (100) surface of GaAs nanowire with [0001] growth direction is investigated utilizing first principles method based on density function theory. The adsorption energy, work function, atomic structure and electronic property of clean surface and Cs-covered surfaces with different coverage are discussed. Results show that when only one Cs is adsorbed on the surface, the most favorable adsorption site is BGa-As. With increasing Cs coverage, work function gradually decreases and gets its minimum at 0.75 ML, then rises slightly when Cs coverage comes to 1 ML, indicating the existence of 'Cs-kill' phenomenon. According to further analysis, Cs activation process can effectively reduce the work function due to the formation of a downward band bending region and surface dipole moment directing from Cs adatom to the surface. As Cs coverage increases, the conduction band minimum and valence band maximum both shift towards lower energy side, contributed by the orbital hybridization between Cs-5s, Cs-5p states and Ga-4p, As-4s, As-4p states near Fermi level. The theoretical calculations and analysis in this study can improve the Cs activation technology for negative electron affinity optoelectronic devices based on GaAs nanowires, and also provide a reference for the further Cs/O or Cs/NF3 activation process.

Radioecological studies of 137Cs in limnological ecosystems. 137Cs concentrations in water, sediment and fishes at the pond in Saitama prefecture, Japan

International Nuclear Information System (INIS)

Miyake, Sadaaki; Motegi, Misako; Oosawa, Takashi; Nakazawa, Kiyoaki; Izumo, Yoshiro

1998-01-01

The concentrations of 137 Cs in water, sediment and fishes at the pond in Saitama prefecture were determined in order to elucidate the radioecology of 137 Cs in limnological ecosystems. 137 Cs concentration in water was 0.31±0.002 mBq/l (mean±standard error), and so indicated about 3 times higher than that (0.10 mBq/l) for the river in our previous report. 137 Cs concentrations in sediment, carp, Cyprinus carpio, crucian carp, Carassius auratus cuvieri, and Hakuren, Hypophthalmichthys molitrix, were about 20000, 1200, 2400 and 3100 times higher than that of the water, respectively. These concentrations were higher than those of each sample for the river in our previous report. It was so suggested that 137 Cs tended to be accumulated in these samples at the pond more than the nuclide in the river. Moreover, concentration ratios, concentration of 137 Cs in sediment, crucian carp and Hakuren to that of the water, were about 30, 2 and 3 times higher than these of 40 K, respectively, except for carp of which 137 Cs and 40 K concentration ratios were almost same. These results showed difference in accumulation mechanism between 137 Cs and 40 K in these samples, as well as 137 Cs transfer mechanism in the limnological ecosystems in part. (author)

Long-term behaviours of 137Cs in simulated crop fields

International Nuclear Information System (INIS)

Lim, K. M.; Choi, Y. H.; Park, H. K.; Park, D. W.; Lee, W. Y.

1999-01-01

In order to understand the long-term behaviour of 137 Cs in crop fields, root uptake and underground distribution of 137 Cs were investigated through a greenhouse experiment where 137 Cs was mixed with topsoil in culture boxes and rice, soybean and Chinese cabbage were grown for 4 years. Soil-to-plant transfer factors of 137 Cs for hulled rice, rice straw, soybean seed and Chinese cabbage reduced by factors of 3-10 depending on crops, and leaching of 137 Cs from the rice culture box decreased by a factor of about 7, in 3 years. The 137 Cs transfer factor for soybean seed were several times higher than that for hulled rice. The amount of 137 Cs leaching during the growing season of rice was as low as 0.025% of applied activity even in the 1st year. The uniformity of 137 Cs distribution in topsoil tended to improve year by year. The present results may be utilized as basic information for the environmental impact assessment and the counter-measure decision when crop fields are contaminated with 137 Cs

Pre-assessment of dose rates of 134Cs, 137Cs, and 60Co for marine biota from discharge of Haiyang Nuclear Power Plant, China

International Nuclear Information System (INIS)

Li, Jingjing; Liu, Senlin; Zhang, Yongxing; Chen, Ling; Yan, Yuan; Cheng, Weiya; Lou, Hailin; Zhang, Yongbao

2015-01-01

Haiyang Nuclear Power Plant to be built in China was selected as a case for the dose pre-assessment for marine biota in this study. The concentrations of Cs and Co in organisms (turbot, yellow croaker, swimming crab, abalone, sea cucumber, and sea lettuce), seawater, and bottom sediment sampled on-site were measured by neutron activation analysis, and the site-specific transfer parameters (concentration ratios and distribution coefficients) of Cs and Co were calculated. 134 Cs, 137 Cs, and 60 Co activity concentrations in the organisms and the sediment at the site were calculated with the site-specific transfer parameters and the anticipated activity concentrations in the liquid effluent of the nuclear power plant. The ERICA tool was used to estimate the dose rates of 134 Cs, 137 Cs, and 60 Co to the selected organisms based on the biological models developed. The total dose rates of 134 Cs, 137 Cs, and 60 Co to the six organisms were all <0.001 μGy h −1 . - Highlights: • Pre-assessment for biota dose rates from Haiyang Nuclear Power Plant was made. • The site-specific transfer parameters were obtained by neutron activation analysis. • The dose rates of 134 Cs, 137 Cs, and 60 Co to the organisms were <0.001 μGy h −1

Comparison of bilirubin level in term infants born by vaginal delivery and C/S

Directory of Open Access Journals (Sweden)

Ahmad Shah Farhat

2016-12-01

Full Text Available Background: Given the overriding importance of neonatal jaundice and scarcity of studies on the role of route of delivery on its occurrence, this study aimed to investigate the association between neonatal bilirubin level and the route of delivery (i.e., normal vaginal delivery [NVD] and cesarean section [CS]. Methods: This prospective, cross-sectional study was conducted in 2012 in Imam Reza Hospital of Mashhad, Iran, 2012. In all term infants, who met the inclusion criteria, serum bilirubin level was measured by the bili-test device between the second and seventh days after birth. In cases with skin bilirubin level>5 mg/dl, serum bilirubin was also checked. The collected data were analyzed using SPSS, version 16. Results: A total of 182 neonates were enrolled in the study, 56% of whom were male. The mean bilirubin levels in the NVD and CS groups were 9.4±2.9 mg/dl and 9.8±3.4 mg/dl, respectively (P=0.53. Additionally, comparison of the mean bilirubin levels between the two groups based of demographic characteristics demonstrated no significant differences. Conclusion: This study showed no significant correlation between neonatal jaundice in term infants and the route of delivery.

Radioecological studies of {sup 137}Cs in limnological ecosystems. Biochemical states of {sup 137}Cs accumulated in killifish (Medaka, Oryzias latipes) meat

Energy Technology Data Exchange (ETDEWEB)

Miyake, Sadaaki; Motegi, Misako; Oosawa, Takashi; Nakazawa, Kiyoaki [Saitama Institute of Public Health, Urawa (Japan); Izumo, Yoshiro; Nakamura, Fumio

1997-07-01

Biochemical states of {sup 137}Cs accumulated in killifish`s (Medaka, Oryzias latipes) meat were investigated in order to elucidate the accumulation mechanism of the radionuclide in goldfish, Carassius auratus auratus, examined in our preceding report. Most of {sup 137}Cs radioactivity in the killifish`s raw meat accumulated this radionuclide in the radioactive freshwater, were found in the non-protein nitrogenous compound (NPNC) fraction (>92%), also in the killifish`s control raw meat mixed with {sup 137}Cs, the difference between both meat samples was not clear. As the results of gel filtration profiles on Sephadex G-25 for the NPNC fraction of these meats, each only one radioactive peak was shown, also similar to {sup 137}CsCl solution. Moreover, these peaks appeared at the same position. On the other hand, the peak positions absorbed at OD{sub 280nm} in the samples were different from those of each radioactive peak. It was so suggested that {sup 137}Cs accumulated in the killifish`s meat was shown not to be binding to protein`s composition. Furthermore, as the results on thin-layer chromatography, ion-exchange resin chromatography and reaction with {sup 137}Cs in samples and ammonium phosphomolybdate, {sup 137}Cs in the NPNC fraction of the killifish`s meat was not almost different from those of each control and {sup 137}CsCl solution. (author)

Exposure of a herbivorous fish to 134Cs and 137Cs from the riverbed following the Fukushima disaster

International Nuclear Information System (INIS)

Tsuboi, Jun-ichi; Abe, Shin-ichiro; Fujimoto, Ken; Kaeriyama, Hideki; Ambe, Daisuke; Matsuda, Keishi; Enomoto, Masahiro; Tomiya, Atsushi; Morita, Takami; Ono, Tsuneo; Yamamoto, Shoichiro; Iguchi, Kei'ichiro

2015-01-01

Ayu Plecoglossus altivelis, a herbivorous fish, is an important fishery resource and key component of the foodweb in many Japanese streams. Radionuclide contamination of this species is likely transferred to higher trophic levels, include humans, in the food chain. After the Fukushima accident in March 2011, ayu were exposed to highly contaminated silt while feeding on algae attached to the riverbed stones. To understand the route by which herbivorous fish are exposed to radionuclides, the activity concentrations of sum of 134 Cs and 137 Cs (radiocesium) were analyzed in riverbed samples (algae and silt) and in the internal organs and the muscle of ayu in five river systems in the Fukushima Prefecture between summer 2011 and autumn 2013. Although there was a positive correlation between the radiocesium activity concentrations in the muscle and the internal organs of ayu, the median activity concentration in the muscle was much lower than those in the internal organs. The activity concentrations of radiocesium in the riverbed samples and the internal organs and the muscle of ayu were correlated with contamination levels in soil samples taken from the watershed upstream of the sample sites. The results of the generalized linear mixed models suggest that the activity concentrations in both the internal organs and the muscle of ayu declined over time. Additionally, the activity concentrations in the internal organs were correlated with those in the riverbed samples that were collected around the same time as the ayu. The activity concentrations in the muscle were correlated with ayu body size. Our results suggest that ayu ingest 134 Cs and 137 Cs while grazing silt and algae from the riverbed, and a part of the 134 Cs and 137 Cs is assimilated into the muscle of the fish. - Highlights: • The radiocesium (sum of 134 Cs and 137 Cs) concentrations in a herbivorous fish were measured following the Fukushima disaster. • The muscle concentrations were correlated with

The concentration of 137Cs and stable Cs in zooplankton in the western North Pacific in relation to their taxonomic composition

International Nuclear Information System (INIS)

Kaeriyama, Hideki; Watabe, Teruhisa; Kusakabe, Masashi

2008-01-01

The objective of this study is to obtain information on the background level of 137 Cs in zooplankton in the waters close to Rokkasho-mura in Aomori Prefecture, Japan, where a large-scale project has been progressively promoted to establish the nuclear fuel cycle. Prior to the full-scale operation of the spent nuclear fuel reprocessing plant, zooplankton samples were collected in May and October 2005, June 2006, and June 2007 from the surface water (0-5 m depth). The samples were analyzed to determine the concentrations of 137 Cs and stable Cs in relation to taxonomic composition. The numerical abundance of the plankton varied from 253 to 1514 inds. m -3 . Taxonomic composition differed between the two sampling periods. Although copepods formed the most abundant taxonomic group during both seasons, gelatinous plankton (chaetognaths, siphonophores, appendicularians and doliolids) were more abundant in October 2005 than in June 2006 and June 2007. The concentration of 137 Cs in zooplankton varied from 11 to 24 mBq kg-WW -1 . At the same station, the 137 Cs concentration in zooplankton in October 2005 was almost twice as much as that in June 2006, although the concentration of 137 Cs in seawater did not show a difference. The concentration of stable Cs was measured for each taxonomic group: that in gelatinous zooplankton (chaetognaths) was higher than that in crustacean zooplankton (copepods, euphausiids and amphipods). These results suggest that the concentration of 137 Cs in zooplankton is affected by the occurrence of gelatinous zooplankton. (author)

Quantitative Cs-137 distributions from airborne gamma ray data

International Nuclear Information System (INIS)

Oberlercher, G.; Seiberl, W.

1997-01-01

The Chernobyl reactor accident caused in Austria Cs-137 activities up to 180 kBq/m 2 . The following paper explains how airborne NaJ-spectroscopy, originally designed for geological surveys, was used as an accurate method to obtain the ground activity of Cs-137 in certain regions of Austria. To retrieve the net count rate in a Cs-137 window it is necessary to subtract all background contributions from the peak, including the Compton continuum and the contribution of overlapping peaks. Therefore the measurement of Cs-137 with a NaJ detector system must take into account radioactive elements with gamma-ray lines near the peak energy of Cs-137 at 662 keV. In regions with higher concentrations of the natural radioactive elements uranium and thorium a peak near 600 keV is found, containing the 609 keV line of Bi-214 and the 585 keV line of TI-208. Additionally a Cs-134 line is located at 604 keV. Because of the poor energy resolution of NaJ detectors it is not possible to find a clear separation between these peaks and the Cs-137 peak. The following section describes the method that was used to obtain accurate quantified Cs-137 activity values. (author)

Pre-assessment of dose rates of (134)Cs, (137)Cs, and (60)Co for marine biota from discharge of Haiyang Nuclear Power Plant, China.

Science.gov (United States)

Li, Jingjing; Liu, Senlin; Zhang, Yongxing; Chen, Ling; Yan, Yuan; Cheng, Weiya; Lou, Hailin; Zhang, Yongbao

2015-09-01

Haiyang Nuclear Power Plant to be built in China was selected as a case for the dose pre-assessment for marine biota in this study. The concentrations of Cs and Co in organisms (turbot, yellow croaker, swimming crab, abalone, sea cucumber, and sea lettuce), seawater, and bottom sediment sampled on-site were measured by neutron activation analysis, and the site-specific transfer parameters (concentration ratios and distribution coefficients) of Cs and Co were calculated. (134)Cs, (137)Cs, and (60)Co activity concentrations in the organisms and the sediment at the site were calculated with the site-specific transfer parameters and the anticipated activity concentrations in the liquid effluent of the nuclear power plant. The ERICA tool was used to estimate the dose rates of (134)Cs, (137)Cs, and (60)Co to the selected organisms based on the biological models developed. The total dose rates of (134)Cs, (137)Cs, and (60)Co to the six organisms were all <0.001 μGy h(-1). Copyright © 2015 Elsevier Ltd. All rights reserved.

Cs-137 in Arctic foxes (Alopex lagopus) on Svalbard

International Nuclear Information System (INIS)

Gwynn, Justin P.; Fuglei, Eva; Dowdall, Mark

2007-01-01

This study presents 137 Cs muscle activity concentrations in Arctic foxes (Alopex lagopus) from Svalbard over a period of several years and discusses the transfer of 137 Cs to Arctic foxes through likely predator-prey relationships. Mean 137 Cs activity concentrations and 137 Cs T ag values (per trapping season) ranged from 0.51 ± 2.76 to 1.32 ± 2.89 Bq/kg (w.w.) and 5.1 x 10 -4 to 1.3 x 10 -3 m 2 /kg, respectively. Mean concentration ratios of 137 Cs in Arctic foxes compared to probable prey ranged from 1.0 to 7.9. On Svalbard, transfer of 137 Cs to Arctic foxes is likely to occur via both marine and terrestrial food chains. The relative contribution of marine and terrestrial food sources to the diet of Arctic foxes may vary by location and by season and may lead to either an increase or decrease in the trophic transfer of 137 Cs to Arctic foxes compared to transfer resulting from terrestrial only diets

Calcium carbonate formation on mica supported extracellular polymeric substance produced by Rhodococcus opacus

Energy Technology Data Exchange (ETDEWEB)

Szcześ, Aleksandra, E-mail: aszczes@poczta.umcs.lublin.pl [Department of Physical Chemistry – Interfacial Phenomena, Faculty of Chemistry, Maria Curie-Skłodowska University, Lublin 20-031 (Poland); Czemierska, Magdalena; Jarosz-Wilkołazka, Anna [Department of Biochemistry, Maria Curie-Skłodowska University, Lublin 20-031 (Poland)

2016-10-15

Extracellular polymeric substance (EPS) extracted from Rhodococcus opacus bacterial strain was used as a matrix for calcium carbonate precipitation using the vapour diffusion method. The total exopolymer and water-soluble exopolymer fraction of different concentrations were spread on the mica surface by the spin-coating method. The obtained layers were characterized using the atomic force microscopy measurement and XPS analysis. The effects of polymer concentration, initial pH of calcium chloride solution and precipitation time on the obtained crystals properties were investigated. Raman spectroscopy and scanning electron microscopy were used to characterize the precipitated minerals. It was found that the type of precipitated CaCO{sub 3} polymorph and the crystal size depend on the kind of EPS fraction. The obtained results indicates that the water soluble fraction favours vaterite dissolution and calcite growth, whereas the total EPS stabilizes vaterite and this effect is stronger at basic pH. It seems to be due to different contents of the functional group of EPS fractions. - Highlights: • CaCO{sub 3} crystal size and polymorph can be controlled by EPS substance obtained from R. opacus. • The water soluble fraction favours vaterite dissolution and calcite growth. • The total EPS stabilizes vaterite. • This effect is stronger at basic pH.

Rhodococcus equi venous catheter infection: a case report and review of the literature

Directory of Open Access Journals (Sweden)

Nahleh Zeina

2011-08-01

Full Text Available Abstract Introduction Rhodococcus equi is an animal pathogen that was initially isolated from horses and is being increasingly reported as a cause of infection in humans with impaired cellular immunity. However, this pathogen is underestimated as a challenging antagonist and is frequently considered to be a mere contaminant despite the potential for life-threatening infections. Most case reports have occurred in immunocompromised patients who have received organ transplants (for example kidney, heart, bone marrow or those with human immunodeficiency virus infection. Infections often manifest as pulmonary involvement or soft tissue abscesses. Bacteremia related to R. equi infections of tunneled central venous catheters has rarely been described. Case presentation We report the case of a 63-year-old non-transplant recipient, non-HIV infected Caucasian woman with endometrial carcinoma who developed recurrent bloodstream infections and septic shock due to R. equi and ultimately required the removal of her port catheter, a subcutaneous implantable central venous catheter. We also review the medical literature related to human infections with R. equi. Conclusion R. equi should be considered a serious pathogen, not a contaminant, particularly in an immunocompromised patient who presents with a central venous catheter-related bloodstream infection. Counseling patients with central venous catheters who participate in activities involving exposure to domesticated animals is recommended.

Calcium carbonate formation on mica supported extracellular polymeric substance produced by Rhodococcus opacus

International Nuclear Information System (INIS)

Szcześ, Aleksandra; Czemierska, Magdalena; Jarosz-Wilkołazka, Anna

2016-01-01

Extracellular polymeric substance (EPS) extracted from Rhodococcus opacus bacterial strain was used as a matrix for calcium carbonate precipitation using the vapour diffusion method. The total exopolymer and water-soluble exopolymer fraction of different concentrations were spread on the mica surface by the spin-coating method. The obtained layers were characterized using the atomic force microscopy measurement and XPS analysis. The effects of polymer concentration, initial pH of calcium chloride solution and precipitation time on the obtained crystals properties were investigated. Raman spectroscopy and scanning electron microscopy were used to characterize the precipitated minerals. It was found that the type of precipitated CaCO 3 polymorph and the crystal size depend on the kind of EPS fraction. The obtained results indicates that the water soluble fraction favours vaterite dissolution and calcite growth, whereas the total EPS stabilizes vaterite and this effect is stronger at basic pH. It seems to be due to different contents of the functional group of EPS fractions. - Highlights: • CaCO 3 crystal size and polymorph can be controlled by EPS substance obtained from R. opacus. • The water soluble fraction favours vaterite dissolution and calcite growth. • The total EPS stabilizes vaterite. • This effect is stronger at basic pH.

{sup 137}Cs distribution in guava trees

Energy Technology Data Exchange (ETDEWEB)

Mosquera, B.; Veiga, R.; Mangia, L.; Carvalho, C.; Estellita, L.; Uzeda, D.; Facure, A.; Violini, B.; Anjos, R.M. [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Inst. de Fisica

2004-09-15

This paper presents results of {sup 137}Cs concentration measured from a guava tree cultivated after the first decontamination work of one of the sites where the worst Brazilian radiological accident occurred. The present work aims to verify how the {sup 137}Cs is transported and distributed along the tropical trees. Bi-dimensional analyses of the radial distribution of {sup 137}Cs in the main trunk are also presented. Neither symmetrical nor homogeneous behaviors of the specific activity distribution in the tree rings were observed. (author)

Long-term distribution of Cs-137 in freshwater ecosystem and the effect of bioturbation on leakage of Cs-137 from the sediments

International Nuclear Information System (INIS)

Aquilonius, K.

1995-06-01

The first aim of the project was to make a literature compilation regarding Cs-137 in freshwater systems. Secondly, in order to follow up the long-term behaviour of Cs-137 in Lake Hillesjoen, sediment and water was sampled with respect to Cs-137. Finally, an experiment was done with chironomids, with the aim to assess the impact of bioturbation on the leakage of Cs-137 from the sediment, since this is one of the factors contributing to the uncertainties in radioecological models. Some aspects of long-term distribution of Cs-137 in freshwater lakes is discussed. In lake Hillesjoen the pool of Cs-137 in sediments (225 kBq/m 2 , 1993) has gradually increased since the Chernobyl accident, and now exceeds the initial deposition (100 kBq/m 2 ). The effect of bioturbation on the leakage from the sediment to the water could not be clarified in this experiment, but is discussed. 40 refs

Synthesis, thermal decomposition and sensitivity study of CsDNBF

Energy Technology Data Exchange (ETDEWEB)

Wang, Shaozong; Zhang, Tonglai; Yang, Li; Zhang, Jianguo; Sun, Yuanhua [State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081 (China)

2007-02-15

CsDNBF (cesium 7-hydroxy-4,6-dinitro-5,7-dihydrobenzofuroxanide) was synthesized from the sodium salt of DNBF and cesium nitrate. The thermal decomposition process has been investigated and the results show that the solid residues at 240 C are RCOOCs, CsNCO, RNO{sub 2} and CsNO{sub 3}. The sensitivity results demonstrate that CsDNBF has better properties than KDNBF, which has been widely used. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

ENC 98

International Nuclear Information System (INIS)

1998-01-01

This press dossier document reports on the main points presented by the Framatome group at the ENC'98 colloquium which took place in Nice (France) on September 25 1998. The summary comprises 4 main parts: the 1997-98 highlights (nuclear realizations in France, China and Turkey, nuclear services, nuclear fuels), the international activities in the nuclear domain (USA, China, Eastern Europe), the research and development activities (the French-German joint EPR project, the high temperature reactor (HTR) project), and the service and nuclear fuel activities (maintenance, improvements, control and expertise). (J.S.)

Chemical information on tank supernatants, Cs adsorption from tank liquids onto Hanford sediments, and field observations of Cs migration from past tank leaks

Energy Technology Data Exchange (ETDEWEB)

Serne, R.J.; Zachara, J.M.; Burke, D.S.

1998-01-01

Borehole gamma-logging profiles beneath the SX-Tank Farm suggest that contamination from Cs-137 extends to at least a depth of 40 m (130 ft), and may extend even deeper. What is presently not known is the pathway that Cs-137 has taken to reach these depths. In this report we provide an analysis of the chemistry of tank supernates with emphasis on the REDOX waste stream disposed in SX tanks, Cs chemistry in aqueous solutions and adsorption properties onto minerals, available data on Cs adsorption onto Hanford sediments, and information on Cs migration from other Hanford tank leaks that have been studied. The data in this report was used to help guide the vadose zone transport analysis of the SX Tank Farm presented in a companion report. The goal of the vadose zone transport modelling is to attempt to explain the depth and extent of the Cs-137 plume under the SX Tank farm, specifically in the vicinity of the greatest leak, near the SX-109 Tank as inferred from the gamma logs (DOE 1996). In solution Cs is present as the monovalent cation and shows very little tendency to form aqueous complexes with inorganic or organic ligands. Cs is expected to adsorb primarily onto selective minerals that have unique adsorption sites. The small Cs{sup +} ion is accommodated on these frayed edge and interlayer sites. Adsorption within the interlayers often leads to collapse of the layers such that the Cs{sup +} ion is effectively trapped and not readily exchangeable by all other common cations. The degree of adsorption is thus only moderately dependent on the types and high concentrations of other cations in leaking tank liquors.

Chemical information on tank supernatants, Cs adsorption from tank liquids onto Hanford sediments, and field observations of Cs migration from past tank leaks

International Nuclear Information System (INIS)

Serne, R.J.; Zachara, J.M.; Burke, D.S.

1998-01-01

Borehole gamma-logging profiles beneath the SX-Tank Farm suggest that contamination from Cs-137 extends to at least a depth of 40 m (130 ft), and may extend even deeper. What is presently not known is the pathway that Cs-137 has taken to reach these depths. In this report we provide an analysis of the chemistry of tank supernates with emphasis on the REDOX waste stream disposed in SX tanks, Cs chemistry in aqueous solutions and adsorption properties onto minerals, available data on Cs adsorption onto Hanford sediments, and information on Cs migration from other Hanford tank leaks that have been studied. The data in this report was used to help guide the vadose zone transport analysis of the SX Tank Farm presented in a companion report. The goal of the vadose zone transport modelling is to attempt to explain the depth and extent of the Cs-137 plume under the SX Tank farm, specifically in the vicinity of the greatest leak, near the SX-109 Tank as inferred from the gamma logs (DOE 1996). In solution Cs is present as the monovalent cation and shows very little tendency to form aqueous complexes with inorganic or organic ligands. Cs is expected to adsorb primarily onto selective minerals that have unique adsorption sites. The small Cs + ion is accommodated on these frayed edge and interlayer sites. Adsorption within the interlayers often leads to collapse of the layers such that the Cs + ion is effectively trapped and not readily exchangeable by all other common cations. The degree of adsorption is thus only moderately dependent on the types and high concentrations of other cations in leaking tank liquors

Absorption spectra of CsNd(MoO4)2 and CsGd(MoO4)2-Nd3+ crystals in strong magnetic fields

International Nuclear Information System (INIS)

Gorban', I.S.; Kozeeva, L.P.; Slobodyanyuk, A.V.; Shevchenko, V.A.

1987-01-01

The comparison of the electronic structure of Nd 3+ in CsNd(MoO 4 ) 2 and CsGd(MoO 4 ) 2 - Nd 3+ crystals is made. It is established that in these crystals the activator centers, mainly, of the certain type with the symmetry of the local environment C 2 are formed. The absorption spectra of self-activated CsNd(MoO 4 ) 2 crystal differ from spectra of CsGd(MoO 4 ) 2 - Nd 3+ by the presence of the vibrating structure. The Stark splittings of energy levels of Nd 3+ in the investigated crystalline matrices are more sensitive to the environment effect than the Zeeman ones. The ground state of Nd 3+ ion in CsNd(MoO 4 ) 2 and CsGd(MoO 4 ) 2 molybdates is characterized by the similar values of g-factors

133Cs NMR investigation of 2D frustrated Heisenberg antiferromagnet, Cs2CuCl4

Science.gov (United States)

Vachon, M.-A.; Kundhikanjana, W.; Straub, A.; Mitrovic, V. F.; Reyes, A. P.; Kuhns, P.; Coldea, R.; Tylczynski, Z.

2006-10-01

We report 133Cs nuclear magnetic resonance (NMR) measurements on the 2D frustrated Heisenberg antiferromagnet Cs2CuCl4 down to 2 K and up to 15 T. We show that 133Cs NMR is a good probe of the magnetic degrees of freedom in this material. Cu spin degrees of freedom are sensed through a strong anisotropic hyperfine coupling. The spin excitation gap opens above the critical saturation field. The gap value was determined from the activation energy of the nuclear spin-lattice relaxation rate in a magnetic field applied parallel to the Cu chains (\\skew3\\hat{b} axis). The values of the g-factor and the saturation field are consistent with the neutron-scattering and magnetization results. The measurements of the spin spin relaxation time are exploited to show that no structural changes occur down to the lowest temperatures investigated.

Initial interaction of {sup 137}Cs with soils

Energy Technology Data Exchange (ETDEWEB)

Nagasaki, S., E-mail: nagasaki@mcmaster.ca [McMaster Univ., Hamilton, Ontario (Canada); Makino, H.; Saito, T. [Univ. of Toyko, Tokyo (Japan)

2013-07-01

It is critical to understand the physicochemical behaviour of Cs in soil in order to progress the decontamination of soils which were contaminated by nuclear power plant accident and to improve the reliability of safety assessment of used nuclear fuel disposal. In this paper, the initial interactions of {sup 137}Cs with soils, which were sampled in Fukushima 38 days after Fukushima Accident, were investigated with sequential extraction method. It was found that there were fast and slow processes of fixation of {sup 137}Cs in clay minerals and that the organic substances might play an important role on kinetics of {sup 137}Cs in soils. (author)

Uptake of Cs 137 from farmland 1986-1989

International Nuclear Information System (INIS)

Holmberg, M.

1986-12-01

The basic mechanisms of the accumulation of Cs 137 in grass, corn, oleiferous plants, potatoes etc are described. It is also presented as a function of time after the deposition. Transport of Cs 137 to milk, meat and bacon is described. A prognosis of Cs 137 in food products for the coming two years is made on basis of the estimated data. (G.B.)

137Cs in man due to nuclear fallout

International Nuclear Information System (INIS)

Poulheim, K.F.

1981-01-01

137 Cs has been determined in man with the aid of a whole-body counter. It is shown that the specific 137 Cs content (as related to the potassium content in man) continuously decreased from 1965 through 1974. After a slight increase in 1975, possibly caused by a Chinese atmospheric nuclear test in June 1974, the 137 Cs content again decreased in the following years. (author)

The radiation chemistry of the Cs-7SB modifier used in Cs and Sr extraction

International Nuclear Information System (INIS)

Swancutt, Katy L.; Cullen, Thomas D.; Mezyk, Stephen P.; Elias, Gracy; Bauer, William F.; Peterman, Dean R.; Riddle, Catherine L.; Ball, R. Duane; Mincher, Bruce J.; Muller, James J.

2011-01-01

The compound 1-(2,2,3,3,-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol, also called Cs-7SB, is used as a solvent modifier in formulations containing calixarenes and crown ethers for cesium and/or strontium extraction from nuclear waste solutions. The compound solvates complexes of both metals and concentration decreases result in lowered extraction efficiency for both. The use of Cs-7SB in nuclear solvent extraction ensures that it will be exposed to high radiation doses, and thus its radiation chemical robustness is a matter of interest in the design of extraction systems employing it. The behavior of the compound in irradiated solution, both in the presence and absence of a nitric acid aqueous phase was investigated here using steady state and pulsed radiolysis techniques. The rate constants for the aqueous reactions of Cs-7SB with H, OH, NO 3 and NO 2 radicals are reported. UPLC-UV-MS results were used to identify major products of the radiolysis of Cs-7SB in contact with nitric acid, and revealed the production of hydroxylated nitro-derivatives. Reaction mechanisms are proposed and it is concluded that the aryl ether configuration of this molecule makes it especially susceptible to nitration in the presence of radiolytically-produced nitrous acid. Fluoride yields are also given under various conditions.

Measurement limits to 134Cs concentration in soil

International Nuclear Information System (INIS)

Ahn, J.K.; Kim, J.S.; Lee, H.M.; Kim, H.; Kim, T.H.; Park, J.N.; Kang, Y.S.; Lee, H.S.; Kim, S.J.; Park, J.Y.; Ryu, S.Y.; Kim, H.-Ch.; Kang, W.G.; Kim, S.K.

2011-01-01

We investigate the caesium concentrations in soils in mountain areas near Gori nuclear power plant in Korea, focusing on the measurement limits to the 134 Cs. In order to lower the minimum detectable amount (MDA) of activity for the 134 Cs, we have used the ammonium molybdophosphate (AMP) precipitation method to get rid of the 40 K existing in natural radioactivity, which reduces the MDA activity about 10 times smaller than those without the AMP precipitation method. The MDA results for the 134 Cs were found to be in the range between 0.015 and 0.044 Bq/kg-dry weight. In order to diminish the background, we also have measured a part of the soil samples in Yangyang, a small town in the east coast of Korea. However, it turns out that in order to detect the 134 Cs in the samples the MDA should be reduced to the level of mBq/kg-dry weight. - Highlights: → We study the caesium concentrations in soils in mountain areas near Gori NPT in Korea. → We use the AMP precipitation method to lower the minimum detectable amount (MDA) of activity for the 134 Cs. → The results of the MDA for the 134 Cs turn out to be in the range between 0.015 and 0.044. → In order to detect the 134 Cs in the samples, the MDA should be reduced to the level of mBq/kg-dry weight.

134Cs and 137Cs whole-body measurements and internal dosimetry of the population living in areas contaminated by radioactivity after the Chernobyl accident

International Nuclear Information System (INIS)

Zvonova, I.A.; Jesko, T.V.; Balonov, M.I.; Danilova, I.O.; Wallstroem, E.; Alpsten, M.; Thornberg, C.; Mattsson, S.

1995-01-01

Six western districts of the Bryansk region, Russia, were heavily contaminated with radioactive fallout after the Chernobyl NPP accident. Annually, between 1991 and 1994, inhabitants of four settlements were studied. Whole-body 134+137 Cs contents were measured in about 500 inhabitants. No correlation between Cs whole-body content and Cs soil contamination was found; Cs accumulation in a body depends greatly on natural factors such as type of soil, on social factors such as food habits including consumption of forest products, and on countermeasures to reduce internal exposure. During 1991-1994 average whole-body content of 134+137 Cs in adult inhabitants was about 3-60 kBq, corresponding to an effective dose of 0.1-2.4 mSv.y -1 . Cs whole-body content increases equally for girls and boys up to adult age. Cs content in adults does not depend significantly on age and is usually 1.2-2 times higher in men than in women. The average annual internal effective dose varies with age significantly less than 134+137 Cs whole-body content. In children (0-5 years) the mean absorbed dose is usually 1.2-1.5 times less than in adults. (author)

Room-temperature synthesis of pure perovskite-related Cs4PbBr6 nanocrystals and their ligand-mediated evolution into highly luminescent CsPbBr3 nanosheets

Science.gov (United States)

Yang, Liu; Li, Dongmei; Wang, Cong; Yao, Wei; Wang, Hao; Huang, Kaixiang

2017-07-01

Currently, all-inorganic cesium lead-halide perovskite nanocrystals have attracted enormous attentions owing to their excellent optical performances. While great efforts have been devoted to CsPbBr3 nanocrystals, the perovskite-related Cs4PbBr6 nanocrystals, which were newly reported, still remained poorly understood. Here, we reported a novel room-temperature reaction strategy to synthesize pure perovskite-related Cs4PbBr6 nanocrystals. Size of the products could be adjusted through altering the amount of ligands, simply. A mixture of two good solvents with different polarity was innovatively used as precursor solvent, being one key to the high-yield Cs4PbBr6 nanocrystals synthesis. Other two keys were Cs+ precursor concentration and surface ligands. Ingenious experiments were designed to reveal the underlying reaction mechanism. No excitonic emission was observed from the prepared Cs4PbBr6 nanocrystals in our work. We considered the green emission which was observed in other reports originated from the avoidless transformation of Cs4PbBr6 into CsPbBr3 nanocrystals. Indeed, the new-prepared Cs4PbBr6 nanocrystals could transform into CsPbBr3 nanosheets with surface ligands mediated. The new-transformed two-dimensional CsPbBr3 nanosheets could evolve into large-size nanosheets. The influences of surface ligand density on the fluorescent intensity and stability of transformed CsPbBr3 nanosheets were also explained. Notably, the photoluminescence quantum yield of the as-transformed CsPbBr3 nanosheets could reach as high as 61.6% in the form of thin film. The fast large-scale synthesis of Cs4PbBr6 nanocrystals and their ligand-mediated transformation into high-fluorescent CsPbBr3 nanosheets will be beneficial to the future optoelectronic applications. Our work provides new approaches to understand the structural evolution and light-emitting principle of perovskite nanocrystals. [Figure not available: see fulltext.

Theoretical investigation of the Cs*Hen>=3 exciplexes

International Nuclear Information System (INIS)

Zbiri, Mohamed; Daul, Claude

2005-01-01

The X 2 Σ 1/2 , A 2 Π 1/2 , B 2 Σ 1/2 , and A 2 Π 3/2 states of Cs*He n exciplexes, with n={3,...,9}, are studied using first principle density functional theory (DFT) formalism combined with the zeroth order regular approximation (ZORA). The zero points energies (ZPEs) E 0 for Cs*He n are calculated at a first step, in order to estimate the stability of the studied exciplexes. Relativistic calculations are carried out including spin-orbit effect (SO), and potential energy surfaces of Cs*He 6 are shown. The electronic distribution shapes of the studied molecules are also discussed, and their emission lines are evaluated and compared to a new discovered experimental emission spectra, which has been recently assigned, using a semi-empirical model, to Cs(AΠ 1/2 )He 7 . Our first principle calculation suggests that the discovered emission line is most probably due to a decay of Cs(AΠ 1/2 )He 6

Dual Two-Component Regulatory Systems Are Involved in Aromatic Compound Degradation in a Polychlorinated-Biphenyl Degrader, Rhodococcus jostii RHA1 ▿ †

OpenAIRE

Takeda, Hisashi; Shimodaira, Jun; Yukawa, Kiyoshi; Hara, Naho; Kasai, Daisuke; Miyauchi, Keisuke; Masai, Eiji; Fukuda, Masao

2010-01-01

A Gram-positive polychlorinated-biphenyl (PCB) degrader, Rhodococcus jostii RHA1, degrades PCBs by cometabolism with biphenyl. A two-component BphS1T1 system encoded by bphS1 and bphT1 (formerly bphS and bphT) is responsible for the transcription induction of the five gene clusters, bphAaAbAcAdC1B1, etbAa1Ab1CbphD1, etbAa2Ab2AcD2, etbAdbphB2, and etbD1, which constitute multiple enzyme systems for biphenyl/PCB degradation. The bphS2 and bphT2 genes, which encode BphS2 and BphT2, virtually ide...

Photon Reabsorption in Mixed CsPbCl3:CsPbI3 Perovskite Nanocrystal Films for Light-Emitting Diodes

KAUST Repository

Davis, Nathaniel J. L. K.; de la Peñ a, Francisco J.; Tabachnyk, Maxim; Richter, Johannes M.; Lamboll, Robin D.; Booker, Edward P.; Wisnivesky Rocca Rivarola, Florencia; Griffiths, James T.; Ducati, Caterina; Menke, S. Matthew; Deschler, Felix; Greenham, Neil C.

2017-01-01

is significantly reduced. We investigate samples containing mixtures of perovskite nanocrystals with different compositions and study the resulting optical and electrical interactions. We report excitation transfer from CsPbCl3 to CsPbI3 in solution and within a

Crystal structure of CsTb(PO3)4 compound

International Nuclear Information System (INIS)

Palkina, K.K.; Maksimova, S.I.; Kuznetsov, V.G.; Chibiskova, N.T.

1978-01-01

The X-ray structural study of compounds of the CsLn(PO 3 ) 4 series has been made. Found is the presence of two structural types for CsPr(PO 3 ) 4 (cubic and monoclinic modifications), one type for CsNd(PO 3 ) 4 (cubic modification) and for CsTb(PO 3 ) 4 (monoclinic modification). For the CsTb(PO 3 ) 4 monocrystal the lattice parameters are determined: a=7.032 +- 0.001; b=8.705 +- 0.001; c=9.051 +- 0.001 A; α=90 deg, β=90 deg, γ=100 deg, Z=2, V=545.68 A 3 , dsub(exp)=3.70 g/cm 3 . The structure character is presented as infinite chains of (PO 4 ) tetrahedrons, stretched along the ''C'' period. Tb and Cs atoms are rounded by 8 atoms of oxygen. Tb polyhedron are irregular octaapexes or strongly deformed tetragonal antiprisms. Tb-Tb shortest distance is 6.59 A

Modelling 137Cs uptake in plants from undisturbed soil monoliths

International Nuclear Information System (INIS)

Waegeneers, Nadia; Smolders, Erik; Merckx, Roel

2005-01-01

A model predicting 137 Cs uptake in plants was applied on data from artificially contaminated lysimeters. The lysimeter data involve three different crops (beans, ryegrass and lettuce) grown on five different soils between 3 and 5 years after contamination and where soil solution composition was monitored. The mechanistic model predicts plant uptake of 137 Cs from soil solution composition. Predicted K concentrations in the rhizosphere were up to 50-fold below that in the bulk soil solution whereas corresponding 137 Cs concentration gradients were always less pronounced. Predictions of crop 137 Cs content based on rhizosphere soil solution compositions were generally closer to observations than those based on bulk soil solution composition. The model explained 17% (beans) to 91% (lettuce) of the variation in 137 Cs activity concentrations in the plants. The model failed to predict the 137 Cs activity concentration in ryegrass where uptake of the 5-year-old 137 Cs from 3 soils was about 40-fold larger than predicted. The model generally underpredicted crop 137 Cs concentrations at soil solution K concentration below about 1.0 mM. It is concluded that 137 Cs uptake can be predicted from the soil solution composition at adequate K nutrition but that significant uncertainties remain when soil solution K is below 1 mM

A homeostatic-partly dynamic model for Cs-137 in trees

International Nuclear Information System (INIS)

Frissel, M. J.

1994-01-01

To describe the uptake of Cs-137 (hereafter only called Cs) two types of models seem most promising: the simple concentration ratio model and the homeostatic model. The first one calculates the concentration of Cs in the vegetation from the Cs concentration in the soil by applying a multiplication factor which is often called a transfer factor. There is no dynamics in the system, the transfer factor or concentration ratio is a constant, which may depend on the ecological system under study. It is often applied to annual crops. The second type of model assumes that the Cs/K ratio in the soil determines the Cs/K ratio in the vegetation. Also this model is usually static. By taking into account variations of the Cs/K ratio in the soil with time - e.g. as caused by K fertilization - it can be extended into a dynamic model. (author)

Removal of Cs+, Sr2+, and Co2+ ions from the mixture of organics and suspended solids aqueous solutions by zeolites

International Nuclear Information System (INIS)

Fang, Xiang Hong; Fang, Fang; Lu, Chun Hai; Zheng, Lei

2017-01-01

Serving as an excellent adsorbent and inorganic ion exchanger in the water purification field, zeolite 4A has in this work presented a strong capability for purifying radioactive waste, such as Sr 2+ , Cs + , and Co 2+ in water. During the processes of decontamination and decommissioning of suspended solids and organics in low-level radioactive wastewater, the purification performance of zeolite 4A has been studied. Under ambient temperature and neutral condition, zeolite 4A absorbed simulated radionuclides such as Sr 2+ , Cs + , and Co 2+ with an absorption rate of almost 90%. Additionally, in alkaline condition, the adsorption percentage even approached 98.7%. After conducting research on suspended solids and organics of zeolite 4A for the treatment of radionuclides, it was found that the suspended clay was conducive to absorption, whereas the absorption of organics in solution was determined by the species of radionuclides and organics. Therefore, zeolite 4A has considerable potential in the treatment of radioactive wastewater

40 CFR 98.418 - Definitions.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Definitions. 98.418 Section 98.418 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Suppliers of Industrial Greenhouse Gases § 98.418 Definitions. All terms used in...

Pengembangan E-Modul Berbasis Adobe Flash CS6 pada Mata Pelajaran Penataan Barang Dagang

Directory of Open Access Journals (Sweden)

Indah Zahrotul Fauziah

2016-09-01

Full Text Available Abstract: The increasing of technology development gives several new things. They are both the technology development in the general aspect and in education aspect. Those developments demand the educators to develop the innovative learning. One of them is using an interactive multimedia in the form of e-module or electronic module which uses Adobe Flash CS6 application. This research uses Research and Development (R&D method with which the combination between ADDIE procedure and Borg & Gall. It consists of 5 stages: (1 Analysis (Needs Analysis, (2 Design (Media of Learning, (3 Development (Media and Materials Validation, (4 Implementation (Small-scale and Field Try-Out, and Evaluation (Three times of revision. The e-module was validated by two experts for three times containing the early product, after small-scale try-out, and after field try-out. The results of the final validation are 99.31% for media expert validation, 98.61% for materials expert validation, and 90.03% for student validation. Abstrak: Perkembangan teknologi yang sangat pesat menghasilkan hal-hal baru, baik teknologi secara umum maupun perkembangan teknologi dalam dunia pendidikan. Perkembangan teknologi tersebut menuntut pendidik untuk mengembangkan pembelajaran yang inovatif. Salah satunya menggunakan multimedia interaktif yang dikemas dalam bentuk e-modul atau modul elektronik dengan memanfaatkan aplikasi Adobe Flash CS6. Penelitian ini menggunakan metode penelitian dan pengembangan (R&D dengan Prosedur penelitian dan pengembangan (R&D ADDIE yang digabungkan dengan Borg & Gall, meliputi 5 tahap yaitu: (1 Analisis (analisis kebutuhan, (2 Design (media pembelajaran, (3 Development (validasi media dan materi, (4 Implementasi (uji coba terbatas dan uji coba lapangan dan (5 Evaluasi (revisi tiga kali. E-modul ini divalidasi oleh dua validator sebanyak tiga kali, yaitu produk awal, setelah uji coba terbatas, dan setelah uji coba lapangan. Berikut adalah hasil yang diperoleh pada

Distribution of 137Cs in the American Coot (Fulica americana)

International Nuclear Information System (INIS)

Potter, C.M.; Brisbin, I.L. Jr.; McDowell, S.G.; Whicker, F.W.

1989-01-01

Caesium-137 concentrations were determined for major tissue and organ components of Americal Coots (Fulica americana) wintering on two contaminated reactor cooling reservoirs on the US Department of Energy's Savannah River Plant. Concentrations reflected the relative contamination levels of the two reservoirs. A low ratio of 137 Cs in gut contents to that in muscle indicated that the coots used in the study were established winter residents and tissue 137 Cs had probably reached equilibrium with intake. The contributions of each component to the whole body weight and total 137 Cs body burden were calculated. Skeletal muscle exhibited the highest 137 Cs concentrations and comprised 35% of the total 137 Cs body burden. Gut contents represented 17% of the total body burden. Various other organs were intermediate and bone exhibited the lowest 137 Cs concentrations. Linear regressions were determined for 137 Cs concentrations in skeletal muscle, liver, kidney, gastrointestinal (GI) tract tissue and gut contents, as functions of whole-body concentrations. (author)

Chondroitin Sulfate (CS) Lyases: Structure, Function and Application in Therapeutics.

Science.gov (United States)

Rani, Aruna; Patel, Seema; Goyal, Arun

2018-01-01

Glycosaminoglycans (GAGs) such as chondroitin sulfate (CS) are the chief natural polysaccharides which reside in biological tissues mainly in extracellular matrix. These CS along with adhesion molecules and growth factors are involved in central nervous system (CNS) development, cell progression and pathogenesis. The chondroitin lyases are the enzyme that degrade and alter the CS chains and hence modify various signalling pathways involving CS chains. These CS lyases are substrate specific, can precisely manipulate the CS polysaccharides and have various biotechnological, medical and therapeutic applications. These enzymes can be used to produce the unsaturated oligosaccharides, which have immune-modulatory, anti-inflammatory and neuroprotective properties. This review focuses on the major breakthrough of the chondroitin sulfate degrading enzymes, their structures and functioning mechanism. This also provides comprehensive information regarding production, purification, characterization of CS lyases and their major applications, both established as well as emerging ones such as neural development. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

137Cs concentration in some Philippine foods

International Nuclear Information System (INIS)

dela Cruz, B.; Marzan, A.M.; Lagmay, N.; Anden, A.

1977-01-01

The current investigation being made by the Philippine Atomic Research Center on the 137 Cs content of the different foods commonly used by the Filipinos is described and preliminary results are reported. The 137 Cs content is determined radiochemically only for the edible portion of the food

Cs separation from nitric acid solutions of radioactive waste

International Nuclear Information System (INIS)

Heckmann, K.; Pieronczyk, W.; Strnad, J.; Feldmaier, F.

1989-01-01

It was the objective of this study to selectively separate active caesium (Cs-134 and Cs-137) from acid radioactive waste solutions (especially MAW and HAWC). The following 'strategy' was designed for a separation process: synthesis of reagents which are acid-resistant and selective for caesium; precipitation of Cs + and separation of the precipitates by filtration or centrifugation or precipitation of Cs + and separation of the precipitates by flotation; caesium separation by liquid-liquid extraction. As precipitating agents, sodium tetraphenylborate (kalignost) and several of its fluorine derivatives were examined. (orig./RB) [de

Export of 134 Cs and 137 Cs in the Fukushima river systems at heavy rains by Typhoon Roke in September 2011

Directory of Open Access Journals (Sweden)

S. Nagao

2013-10-01

Full Text Available At stations on the Natsui River and the Same River in Fukushima Prefecture, Japan, effects of a heavy rain event on radiocesium export were studied after Typhoon Roke during 21–22 September 2011, six months after the Fukushima Dai-ichi Nuclear Power Plant accident. Radioactivity of 134Cs and 137Cs in river waters was 0.009–0.098 Bq L−1 in normal flow conditions during July–September 2011, but it increased to 0.85 Bq L−1 in high flow conditions because of heavy rains occurring with the typhoon. The particulate fractions of 134Cs and 137Cs were 21–56% of total radiocesium in the normal flow condition, but were close to 100% after the typhoon. These results indicate that the pulse input of radiocesium associated with suspended particles from land to coastal ocean occurred because of the heavy rain event. Export flux of 134Cs and 137Cs attributable to the heavy rain accounts for 30–50% of the annual radiocesium flux from inland to coastal ocean region in 2011. Results show that rain events are one factor contributing to the transport and dispersion of radiocesium in river watersheds and coastal marine environments.

Production of carotenoids and lipids by Rhodococcus opacus PD630 in batch and fed-batch culture.

Science.gov (United States)

Thanapimmetha, Anusith; Suwaleerat, Tharatron; Saisriyoot, Maythee; Chisti, Yusuf; Srinophakun, Penjit

2017-01-01

Production of carotenoids by Rhodococcus opacus PD630 is reported. A modified mineral salt medium formulated with glycerol as an inexpensive carbon source was used for the fermentation. Ammonium acetate was the nitrogen source. A dry cell mass concentration of nearly 5.4 g/L could be produced in shake flasks with a carotenoid concentration of 0.54 mg/L. In batch culture in a 5 L bioreactor, without pH control, the maximum dry biomass concentration was ~30 % lower than in shake flasks and the carotenoids concentration was 0.09 mg/L. Both the biomass concentration and the carotenoids concentration could be raised using a fed-batch operation with a feed mixture of ammonium acetate and acetic acid. With this strategy, the final biomass concentration was 8.2 g/L and the carotenoids concentration was 0.20 mg/L in a 10-day fermentation. A control of pH proved to be unnecessary for maximizing the production of carotenoids in this fermentation.

Nutrient starvation leading to triglyceride accumulation activates the Entner Doudoroff pathway in Rhodococcus jostii RHA1.

Science.gov (United States)

Juarez, Antonio; Villa, Juan A; Lanza, Val F; Lázaro, Beatriz; de la Cruz, Fernando; Alvarez, Héctor M; Moncalián, Gabriel

2017-02-27

Rhodococcus jostii RHA1 and other actinobacteria accumulate triglycerides (TAG) under nutrient starvation. This property has an important biotechnological potential in the production of sustainable oils. To gain insight into the metabolic pathways involved in TAG accumulation, we analysed the transcriptome of R jostii RHA1 under nutrient-limiting conditions. We correlate these physiological conditions with significant changes in cell physiology. The main consequence was a global switch from catabolic to anabolic pathways. Interestingly, the Entner-Doudoroff (ED) pathway was upregulated in detriment of the glycolysis or pentose phosphate pathways. ED induction was independent of the carbon source (either gluconate or glucose). Some of the diacylglycerol acyltransferase genes involved in the last step of the Kennedy pathway were also upregulated. A common feature of the promoter region of most upregulated genes was the presence of a consensus binding sequence for the cAMP-dependent CRP regulator. This is the first experimental observation of an ED shift under nutrient starvation conditions. Knowledge of this switch could help in the design of metabolomic approaches to optimize carbon derivation for single cell oil production.

45 CFR 98.90 - Monitoring.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 1 2010-10-01 2010-10-01 false Monitoring. 98.90 Section 98.90 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CHILD CARE AND DEVELOPMENT FUND Monitoring, Non-compliance and Complaints § 98.90 Monitoring. (a) The Secretary will monitor programs funded under...

29 CFR 98.1000 - Respondent.

Science.gov (United States)

2010-07-01

... 29 Labor 1 2010-07-01 2010-07-01 true Respondent. 98.1000 Section 98.1000 Labor Office of the Secretary of Labor GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 98.1000 Respondent. Respondent means a person against whom an agency has initiated a debarment or suspension action. ...

34 CFR 98.6 - Reports.

Science.gov (United States)

2010-07-01

... 34 Education 1 2010-07-01 2010-07-01 false Reports. 98.6 Section 98.6 Education Office of the Secretary, Department of Education STUDENT RIGHTS IN RESEARCH, EXPERIMENTAL PROGRAMS, AND TESTING § 98.6 Reports. The Secretary may require the recipient to submit reports containing information necessary to...

Effect of minerals on accumulation of Cs by fungus Saccaromyces cerevisiae

International Nuclear Information System (INIS)

Ohnuki, Toshihiko; Sakamoto, Fuminori; Yamasaki, Shinya; Kozai, Naofumi; Shiotsu, Hiroyuki; Utsunomiya, Satoshi; Watanabe, Naoko; Kozaki, Tamotsu

2015-01-01

The accumulation of Cs by unicellular fungus of Saccharomyces cerevisiae in the presence of minerals has been studied to elucidate the role of microorganisms in the migration of radioactive Cs in the environment. Two different types of experiments were employed: experiments using stable Cs to examine the effect of a carbon source on the accumulation of Cs, and accumulation experiments of radioactive Cs from agar medium containing 137 Cs and zeolite, vermiculite, phlogopite, smectite, mica, or illite as mineral supplements. In the former type of experiments, the Cs-accumulated cells were analyzed by scanning electron microscopy equipped with energy dispersive X-ray analysis (SEM-EDS). In the latter type, the radioactivity in the yeast cells was measured by an autoradiography technique. When a carbon source was present, higher amounts of Cs accumulated in the cells than in the resting condition without a carbon source. Analyses with SEM-EDS showed that no mineral formed on the cell surface. These results indicate that the yeast cells accumulate Cs by adsorption on the cell surface and intracellular accumulation. In the presence of minerals in the agar medium, the radioactivity in the yeast cells was in the order of mica > smectite, illite >> vermiculite, phlogopite, zeolite. This order is inversely correlated to the ratio of the concentration of radioactive Cs between the minerals and the medium solution. These results strongly suggest that the yeast accumulates radioactive Cs competitively with minerals. - Graphical abstract: Autoradiography analysis showed that presence of larger amounts of mineral of vermiculite collected in South Africa induced less accumulation of radioactive Cs in yeast cells from the medium. - Highlights: • Effect of minerals on the accumulation of radioactive Cs by yeast was studied. • Presence of minerals reduced accumulation of radioactive Cs by yeast. • The order of reduction is mica>smectite, illite>>vermiculite, phlogopite

Facile synthesis of CsPbBr3/PbSe composite clusters.

Science.gov (United States)

Nguyen, Thang Phan; Ozturk, Abdullah; Park, Jongee; Sohn, Woonbae; Lee, Tae Hyung; Jang, Ho Won; Kim, Soo Young

2018-01-01

In this work, CsPbBr 3 and PbSe nanocomposites were synthesized to protect perovskite material from self-enlargement during reaction. UV absorption and photoluminescence (PL) spectra indicate that the addition of Se into CsPbBr 3 quantum dots modified the electronic structure of CsPbBr 3 , increasing the band gap from 2.38 to 2.48 eV as the Cs:Se ratio increased to 1:3. Thus, the emission color of CsPbBr 3 perovskite quantum dots was modified from green to blue by increasing the Se ratio in composites. According to X-ray diffraction patterns, the structure of CsPbBr 3 quantum dots changed from cubic to orthorhombic due to the introduction of PbSe at the surface. Transmission electron microscopy and X-ray photoemission spectroscopy confirmed that the atomic distribution in CsPbBr 3 /PbSe composite clusters is uniform and the composite materials were well formed. The PL intensity of a CsPbBr 3 /PbSe sample with a 1:1 Cs:Se ratio maintained 50% of its initial intensity after keeping the sample for 81 h in air, while the PL intensity of CsPbBr 3 reduced to 20% of its initial intensity. Therefore, it is considered that low amounts of Se could improve the stability of CsPbBr 3 quantum dots.

Determination of {sup 135}Cs by accelerator mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

MacDonald, C.M.; Charles, C.R.J. [Andre. E. Lalonde AMS Laboratory, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Department of Earth Sciences, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Zhao, X.-L.; Kieser, W.E. [Andre. E. Lalonde AMS Laboratory, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Cornett, R.J. [Andre. E. Lalonde AMS Laboratory, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Department of Earth Sciences, University of Ottawa, 150 Louis Pasteur, Ottawa, ON K1N 6N5 (Canada); Litherland, A.E. [IsoTrace Laboratory, University of Toronto, 60 St. George St., Toronto, ON M5S 1A7 (Canada)

2015-10-15

The ratio of anthropogenic {sup 135}Cs and {sup 137}Cs isotopes is characteristic of a uranium fission source. This research evaluates the technique of isotope dilution (yield tracing) for the purpose of quantifying {sup 135}Cs by accelerator mass spectrometry with on-line isobar separation. Interferences from Ba, Zn{sub 2}, and isotopes of equal mass to charge ratios were successfully suppressed. However, some sample crosstalk from source contamination remains. The transmission and di-fluoride ionization efficiencies of Cs isotopes were found to be 8 × 10{sup −3} and 1.7 × 10{sup −7} respectively. This quantification of {sup 135}Cs using yield tracing by accelerator mass spectrometry shows promise for future environmental sample analysis once the issues of sample crosstalk and low efficiency can be resolved.

The TiO2 Refraction Film for CsI Scintillator

OpenAIRE

C. C. Chen; C. W. Hun; C. J. Wang; C. Y. Chen; J. S. Lin; K. J. Huang

2015-01-01

Cesium iodide (CsI) melt was injected into anodic aluminum oxide (AAO) template and was solidified to CsI column. The controllable AAO channel size (10~500 nm) can makes CsI column size from 10 to 500 nm in diameter. In order to have a shorter light irradiate from each singe CsI column top to bottom the AAO template was coated a TiO2 nano-film. The TiO2 film acts a refraction film and makes X-ray has a shorter irradiation path in the CsI crystal making a stronger the photo-electron signal. Wh...

Dynamic modelling of Cs-137 contamination in Denmark

International Nuclear Information System (INIS)

Oehlenschlaeger, M.

1989-01-01

The paper describes the structure of a dynamic food-chain transport model for Cs-137 in the Danish terrestrial environment. The model solves a set of linear, coupled differential equations in order to estimate the inventories and concentrations of Cs-137 in the soil, vegetation, animal tissue and animal product as a function of time based on the Cs-137 concentrations in the air after an accidental release. Meteorological conditions and seasonal variations in agricultural practice are included. (orig.)

Recent levels of radionuclides in lichens from southwest Poland with particular reference to 134Cs and 137Cs

International Nuclear Information System (INIS)

Seaward, M.R.D.; Bylinska, E.A.

1988-01-01

Analyses of Umbilicaria species collected from southwest Poland in August 1986 have shown there to be significant increases in levels of various radionuclides since previous analyses based on fieldwork in 1978-1979. The composition and ratio of the various radionuclides, particularly in respect of 134 Cs and 137 Cs, exhibit a characteristic signature consistent with contamination derived from the accident at the Chernobyl nuclear reactor in April 1986. Intraspecific variation in levels of 137 Cs in Umbilicaria is related to such factors as location, altitude and, to a lesser degree, aspect; interspecific variation in levels is related to ecological requirements and geographical pattern, and hence the same factors, although morphological differences in thalli may be implicated. (author)

CsPb2Br5 Single Crystals: Synthesis and Characterization

KAUST Repository

Dursun, Ibrahim

2017-08-02

CsPb2Br5 is a ternary halogen-plumbate material with close characteristics to well-reported halide perovskites. Due to its unconventional two-dimensional structure, CsPb2Br5 is being looked at broadly for potential applications in optoelectronics. CsPb2Br5 investigations are currently limited to nanostructures and powder forms of the material, which present unclear and conflicting optical properties. In this study, we present the synthesis and characterization of CsPb2Br5 bulk single crystals, which enabled us to finally clarify the material\\'s optical features. Our CsPb2Br5 crystal has a two-dimensional structure with Pb2Br5- layers spaced by Cs+ cations, and exhibits a ~3.1 eV indirect bandgap with no emission in the visible spectrum.

Concentration factors for 137Cs in Japanese coastal fish (1984-1990)

International Nuclear Information System (INIS)

Tateda, Yutaka; Koyanagi, Taku.

1996-01-01

Concentration factors (CFs; Bq kg -1 wet in fish muscle/Bq kg -1 in filtered seawater) for 137 Cs were determined in Japanese coastal fish collected from 1984 to 1990. 137 Cs/Cs (stable) atom ratios were also examined to clarify the distribution equilibrium of 137 Cs-between marine fish and seawater. The geometric mean of CF in Japanese coastal fish was 52±4 (standard error of the mean), with values ranging from 14 to 133. 137 Cs/Cs atom ratios both in marine fish and seawater indicate that the distribution of 137 Cs was in equilibrium between fish muscle and seawater. Therefore, CF values obtained in the present study can be regarded as equilibrated. Our results show that the CFs for 137 Cs in Japanese coastal fish were within the range of Japanese guidelines, but were below the recommended IAEA value. (author)

On the cesium-rich part of the Cs-Te phase diagram

International Nuclear Information System (INIS)

Boer, R. de; Cordfunke, E.H.P.

1995-03-01

The cesium-tellurium system in the region between 33 and 55 at.% Te has been investigated with X-ray diffraction and DSC. The existence of the compounds Cs 5 Te 3 and CsTe is demonstrated. The latter compound exhibits a structural transition at elevated temperature, as does the compound Cs 2 Te. The earlier reported compounds Cs 3 Te 2 and Cs 5 Te 4 do not exist. (orig.)

Photon Reabsorption in Mixed CsPbCl3:CsPbI3 Perovskite Nanocrystal Films for Light-Emitting Diodes

KAUST Repository

Davis, Nathaniel J. L. K.

2017-01-24

Cesium lead halide nanocrystals, CsPbX3 (X = Cl, Br, I), exhibit photoluminescence quantum efficiencies approaching 100% without the core–shell structures usually used in conventional semiconductor nanocrystals. These high photoluminescence efficiencies make these crystals ideal candidates for light-emitting diodes (LEDs). However, because of the large surface area to volume ratio, halogen exchange between perovskite nanocrystals of different compositions occurs rapidly, which is one of the limiting factors for white-light applications requiring a mixture of different crystal compositions to achieve a broad emission spectrum. Here, we use mixtures of chloride and iodide CsPbX3 (X = Cl, I) perovskite nanocrystals where anion exchange is significantly reduced. We investigate samples containing mixtures of perovskite nanocrystals with different compositions and study the resulting optical and electrical interactions. We report excitation transfer from CsPbCl3 to CsPbI3 in solution and within a poly(methyl methacrylate) matrix via photon reabsorption, which also occurs in electrically excited crystals in bulk heterojunction LEDs.

Electronic structure, photoemission spectra, and vacuum-ultraviolet optical spectra of CsPbCl3 and CsPbBr3

Science.gov (United States)

Heidrich, K.; Schäfer, W.; Schreiber, M.; Söchtig, J.; Trendel, G.; Treusch, J.; Grandke, T.; Stolz, H. J.

1981-11-01

Optical spectra of CsPbCl3 and CsPbBr3 have been measured in the range from 2 to 10 eV and have been combined with ultraviolet-photoemission-spectroscopy (UPS)-measurements at 21.1 and 40.8 eV. A quantitative band calculation is presented, which takes into account anion-anion interaction as well as electronic states of the Cs+ ion. The prominent features of earlier band models and measurements are reestablished through our measurements and calculations, namely that the valence band consists of anionic p functions and Pb 6s functions, the lowest conduction band being Pb 6p type, and the lowest gap occuring at the R point of the Brillouin zone. Inclusion of a further (Cs 6s-type) conduction band, however, is necessary to bring the calculated joint density of states into agreement with vacuum-ultraviolet optical spectra. The calculated densities of states of the valence bands are in quantitative agreement with those deduced from our UPS measurements.

Cs phytoremediation by Sorghum bicolor cultivated in soil and in hydroponic system.

Science.gov (United States)

Wang, Xu; Chen, Can; Wang, Jianlong

2017-04-03

Cs accumulation characteristics by Sorghum bicolor were investigated in hydroponic system (Cs level at 50-1000 μmol/L) and in soil (Cs-spiked concentration was 100 and 400 mg/kg soil). Two varieties of S. bicolor Cowly and Nengsi 2# grown on pot soil during the entire growth period (100 days) did not show significant differences on the height, dry weight (DW), and Cs accumulation. S. bicolor showed the potential phytoextraction ability for Cs-contaminated soil with the bioaccumulation factor (BCF) and the translocation factor (TF) values usually higher than 1 in soil system and in hydroponic system. The aerial parts of S. bicolor contributed to 86-92% of the total removed amounts of Cs from soil. Cs level in solution at 100 μmol/L gave the highest BCF and TF values of S. bicolor. Cs at low level tended to transfer to the aerial parts, whereas Cs at high level decreased the transfer ratio from root to shoot. In soil, the plant grew well when Cs spiked level was 100 mg/kg soil, but was inhibited by Cs at 400 mg/kg soil with Cs content in sorghum reaching 1147 mg/kg (roots), 2473 mg/kg (stems), and 2939 mg/kg (leaves). In hydroponic system, average Cs level in sorghum reached 5270 mg/kg (roots) and 4513 mg/kg (aerial parts), without significant damages to its biomass at 30 days after starting Cs treatment. Cs accumulation in sorghum tissues was positively correlated with the metal concentration in medium.

9 CFR 98.30 - Definitions.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Definitions. 98.30 Section 98.30... EMBRYOS AND ANIMAL SEMEN Certain Animal Semen § 98.30 Definitions. Whenever in this subpart of the... (England, Scotland, Wales, the Isle of Man, and Northern Ireland). Cattle. Animals of the bovine species...

29 CFR 98.1005 - State.

Science.gov (United States)

2010-07-01

... 29 Labor 1 2010-07-01 2010-07-01 true State. 98.1005 Section 98.1005 Labor Office of the Secretary of Labor GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 98.1005 State. (a) State means— (1) Any of the states of the United States; (2) The District of Columbia; (3) The...

In vitro and intra-macrophage gene expression by Rhodococcus equi strain 103.

Science.gov (United States)

Rahman, Md Tanvir; Parreira, Valeria; Prescott, John F

2005-09-30

Rhodococcus equi is a facultative intracellular respiratory pathogen of foals that persists and multiplies within macrophages. In foals, virulence is associated with 80-90 kb plasmids, which include a pathogenicity island (PI) containing the virulence-associated protein (vap) gene family, but detailed understanding of the basis of virulence is still poor. A 60 spot-based DNA microarray was developed containing eight PI genes and 42 chromosomal putative virulence or virulence-associated genes selected from a recent partial genome sequence in order to study transcription of these genes by R. equi grown inside macrophages and under in vitro conditions thought to simulate those of macrophages. In addition to seven PI genes, nine chromosomal genes involved in fatty acid and lipid metabolism (choD, fadD13, fbpB), heme biosynthesis (hemE), iron utilization (mbtF), heat shock resistance and genes encoding chaperones (clpB, groEL), a sigma factor (sigK), and a transcriptional regulator (moxR) were significantly induced in R. equi growing inside macrophages. The pattern of R. equi chromosomal genes significantly transcribed inside macrophages largely differed from those transcribed under in vitro conditions (37 degrees C, pH 5.0 or 50mM H2O2 for 30 min). This study has identified genes, other than those of the virulence plasmid, the transcription of which is enhanced within equine macrophages. These genes should be investigated further to improve understanding of how this organism survives intracellularly.

Dissolution behavior of 137Cs absorbed on the green tea leaves

International Nuclear Information System (INIS)

Oya, Yasuhisa; Uchimura, Hiromichi; Toda, Kensuke; Okuno, Kenji; Ikka, Takashi; Morita, Akio

2013-01-01

The green tea leaves was dipped in the 137 CsCl solution to elucidate the dissolution behavior of 137 Cs contaminated on the green tea leaves. It was found that the amount of 137 Cs dissolved into tea water was controlled by the temperature of water, and the activation energy of 137 Cs dissolution was estimated to be 0.045 eV, indicating that most of 137 Cs would exist as the adsorbed state. In addition, the dissolution behavior was controlled by the concentration of stable Cs dissolved in water, although no large correlation with pH was observed. (author)

Detection of CS in Neptune's atmosphere from ALMA observations

Science.gov (United States)

Moreno, R.; Lellouch, E.; Cavalié, T.; Moullet, A.

2017-12-01

Context. The large and vertically non-uniform abundance of CO in Neptune's atmosphere has been interpreted as the result of past cometary impact(s), either single or distributed in size and time, which could also be at the origin of Neptune's HCN. Aims: We aim to provide observational support for this scenario by searching for other comet-induced species, in particular carbon sulfide (CS) which has been observed continuously in Jupiter since the 1994 Shoemaker-Levy 9 impacts. Methods: In April 2016 we used the ALMA interferometer to search for CS(7-6) at 342.883 GHz in Neptune. Results: We report on the detection of CS in Neptune's atmosphere, the first unambiguous observation of a sulfur-bearing species in a giant planet beyond Jupiter. Carbon sulfide appears to be present only at submillibar levels, with a column density of (2.0-3.1) × 1012 cm-2, and a typical mixing ratio of (2-20) × 10-11 that depends on its precise vertical location. The favoured origin of CS is deposition by a putative large comet impact several centuries ago, and the strong depletion of CS with respect to CO - compared to the Jupiter case - is likely due to the CS sticking to aerosols or clustering to form polymers in Neptune's lower stratosphere. Conclusions: The CS detection, along with recent analyses of the CO profile, reinforces the presumption of a large comet impact into Neptune 1000 yr ago, that delivered CO, CS, and HCN at the same time.

Lattice dynamics of cubic Cs2NaLnX6 and CsNaLn1-xLn'xX6 elpasolites

International Nuclear Information System (INIS)

Acevedo, R.; Poblete, V.; Alzamora, R.; Venegas, R.; Navarro, G.; Henriquez, C.

1999-01-01

Crystal lattice dynamics of stoichiometric Cs 2 NaLnX 6 and nonstoichiometric CsNaLn 1-x Ln' x X 6 , 0.01 ≤ x ≤ 0.10, Ln and Ln' are trivalent positive lanthanide ions and X is chlorine or bromine, were studied.. Phonon dispersion relations were computed for similar compound, Cs 2 UBr 6 , and vibronic absorption spectra with reduced number of required input parameters are considered on the basis of proposed model. (author)

Soil 137Cs background values in monsoon region of china

International Nuclear Information System (INIS)

Zhang Mingli; Yang Hao; Wang Xiaolei; Wang Yihong; Xu Congan; Yang Jiudong; Rong Jing

2009-01-01

Land degradation,, which is resulted from the soil erosion, is one of the major environmental problems. It severely affects the food supplies, environmental safety and the sustainable development in China. Some areas in the monsoon region are suffering from the acute soil erosion. To find out the degree of soil erosion, the proven technique of 137 Cs tracer is definitely one of the best methods, and the key is to ascertain the accuracy of soil 137 Cs background value. The distributions of 137 Cs were explored in soil profiles by detecting the 137 Cs of soil cores from the Yimeng mountain area in Shandong Province, hills in the southern area of Jiangsu Province and Dianchi catchment in Yunnan Province, respectively. We found that the depth of 137 Cs distribution is not the same in the soils of various areas. But the 137 Cs activity shows an exponential distribution in the uncultivated soil and demonstrates a strong correlation with the soil depth, while the 137 Cs activity proves uniform in the soil plowing layer of the cultivated land. The study shows the 137 Cs background values of three areas: 1737.1 Bq/m 2 in Yimeng mountain area, 1847.6 Bq/m 2 in southern area of hills in Jiangsu, 918.0 Bq/m 2 in Dianchi catchment. The certainty of 137 Cs background value can technically support the use of 137 Cs technique to study the spatial pattern of soil erosion, deposition and the land degradation, which provides the support for the sustainable utilization of soil resource, the assessment of economical benefit and loss and the evaluation of water and soil conservation measures. (authors)

Restriction Fragment Length Polymorphisms of Virulence Plasmids in Rhodococcus equi

Science.gov (United States)

Takai, Shinji; Shoda, Masato; Sasaki, Yukako; Tsubaki, Shiro; Fortier, Guillaume; Pronost, Stephane; Rahal, Karim; Becu, Teotimo; Begg, Angela; Browning, Glenn; Nicholson, Vivian M.; Prescott, John F.

1999-01-01

Virulent Rhodococcus equi, which is a well-known cause of pyogranulomatous pneumonia in foals, possesses a large plasmid encoding virulence-associated 15- to 17-kDa antigens. Foal and soil isolates from five countries—Argentina, Australia, Canada, France, and Japan—were investigated for the presence of 15- to 17-kDa antigens by colony blotting, using the monoclonal antibody 10G5, and the gene coding for 15- to 17-kDa antigens by PCR. Plasmid DNAs extracted from positive isolates were digested with restriction endonucleases BamHI, EcoRI, EcoT22I, and HindIII, and the digestion patterns that resulted divided the plasmids of virulent isolates into five closely related types. Three of the five types had already been reported in Canadian and Japanese isolates, and the two new types had been found in French and Japanese isolates. Therefore, we tentatively designated these five types 85-kb type I (pREAT701), 85-kb type II (a new type), 87-kb type I (EcoRI and BamHI type 2 [V. M. Nicholson and J. F. Prescott, J. Clin. Microbiol. 35:738–740, 1997]), 87-kb type II (a new type), and 90-kb (pREL1) plasmids. The 85-kb type I plasmid was found in isolates from Argentina, Australia, Canada, and France. Plasmid 87-kb type I was isolated in specimens from Argentina, Canada, and France. The 85-kb type II plasmid appeared in isolates from France. On the other hand, plasmids 87-kb type II and 90-kb were found only in isolates from Japan. These results revealed geographic differences in the distribution of the virulence plasmids found in the five countries and suggested that the restriction fragment length polymorphism of virulence plasmids might be useful to elucidate the molecular epidemiology of virulent R. equi in the world. PMID:10488224

Effect of minerals on accumulation of Cs by fungus Saccaromyces cerevisiae.

Science.gov (United States)

Ohnuki, Toshihiko; Sakamoto, Fuminori; Yamasaki, Shinya; Kozai, Naofumi; Shiotsu, Hiroyuki; Utsunomiya, Satoshi; Watanabe, Naoko; Kozaki, Tamotsu

2015-06-01

The accumulation of Cs by unicellular fungus of Saccharomyces cerevisiae in the presence of minerals has been studied to elucidate the role of microorganisms in the migration of radioactive Cs in the environment. Two different types of experiments were employed: experiments using stable Cs to examine the effect of a carbon source on the accumulation of Cs, and accumulation experiments of radioactive Cs from agar medium containing (137)Cs and zeolite, vermiculite, phlogopite, smectite, mica, or illite as mineral supplements. In the former type of experiments, the Cs-accumulated cells were analyzed by scanning electron microscopy equipped with energy dispersive X-ray analysis (SEM-EDS). In the latter type, the radioactivity in the yeast cells was measured by an autoradiography technique. When a carbon source was present, higher amounts of Cs accumulated in the cells than in the resting condition without a carbon source. Analyses with SEM-EDS showed that no mineral formed on the cell surface. These results indicate that the yeast cells accumulate Cs by adsorption on the cell surface and intracellular accumulation. In the presence of minerals in the agar medium, the radioactivity in the yeast cells was in the order of mica > smectite, illite > vermiculite, phlogopite, zeolite. This order is inversely correlated to the ratio of the concentration of radioactive Cs between the minerals and the medium solution. These results strongly suggest that the yeast accumulates radioactive Cs competitively with minerals. Copyright © 2015 Elsevier Ltd. All rights reserved.

WESF (173)Cs gamma ray sources

Science.gov (United States)

Kenna, B. T.

1984-10-01

The Waste Encapsulation and Storage Facility (WESP) at Hanford, Washington has been separating cesium from stored liquid defense waste since 1945. This is done to alleviate the heat generated by the decay of radioactive Cs137. The cesium is converted to CsCl, doubly encapsulated in 316l stainless steel, and placed in storage. The potential utility of these Cs137 capsules as gamma radiation sources was demonstrated. Registration of the capsule with the NRC as a sealed gamma source would facilitate the licensing of non-DOE irradiation facilities using this source. To grant this registration, the NRC requires characteristics of the capsule. It must also be demonstrated that the capsule will maintain its integrity under both normal circumstances and specified abnormal conditions. The required information is provided through collation of results of studies and tests done previously by other laboratories.

Experimental and computation method for determination of burnup and isotopic composition of the WWER-440 fuel using the 134Cs and 137Cs concentrations

International Nuclear Information System (INIS)

Babichev, B.A.; Kozharin, V.V.

1990-01-01

An experimental and computational method for determination of burnup and actinoid concentrations in WWER fuel elements using 134 Cs and 137 Cs concentrations in fuel is considered. It is shown that the error in calculation of fuel burnup and U and Pu isotope concentrations in WWER-440 fuel elements is 1.3-4.9% provided that the error in 134 Cs and 137 Cs concentration measurements does not exceed 1.7 and 1.2%. 9 refs.; 10 figs.; 4 tabs

Sequestration and disposal of dissolved Cs+ using zeolite 13X

Science.gov (United States)

Park, M.; Park, J.; Jeong, H. Y.

2017-12-01

Low-to-intermediate level liquid radioactive wastes (LILLW) typically contain high levels of radioactive 137Cs. Due to the great radiational and thermal stability as well as the high selectivity, zeolite has been commonly utilized to sequester radioactive isotopes from nuclear wastewater effluents. In this study, an Al-rich synthetic zeolite 13X was evaluated for the sorption capacity of Cs+ as a function of pH (4.0-10.5), ionic strength (0.05 and 0.2 M), and initial Cs+ concentration (1×10-6-5×10-3 M). For safe disposal, Cs+-exchanged 13X was both thermally and hydrothermally treated under different temperature and pressure. Subsequently, the resultant materials were examined for the phase transition by X-ray diffraction (XRD) and the local coordination chemistry by X-ray absorption spectroscopy (XAS). Our experimental results will detail the Cs+ sorption behavior by 13X under varying solution compositions. Also, the structural changes of Cs+-exchanged 13X upon thermal and hydrothermal treatment will be delineated to assess the stability of Cs+ in the treated materials.

Pulsed Cs beam development for the BNL polarized H- source

International Nuclear Information System (INIS)

Alessi, J.G.

1983-01-01

A pulsed Cs + beam has been developed for use on a polarized H - source. Cesium ion production is by surface ionization using a porous tungsten ionizer. While satisfactory current pulses (5 to 10 mA greater than or equal to 0.5 ms) can be obtained, the pulse shapes are a sensitive function of the ionizer temperature and Cs surface coverage. The beam optical requirements are stringent, and the optics have been studied experimentally for both Cs + and Cs 0 beams. Computer calculations are in good agreement with the observed results. The present source has delivered 2.6 mA of Cs + through the interaction region of the polarized ion source, and as much as 2.0 particle mA of Cs 0 . A new source is being built which is designed to give 15 mA through the interaction region

Speciation of Cs-137 in fertilizers amended soils

International Nuclear Information System (INIS)

Mocanu, N.; Breban, D.C.

1999-01-01

One of the most used agricultural countermeasures to reduce the uptake of radionuclides from soil into plants is the chemical treatment of the soil with fertilizers. The distribution of a radionuclide between different physico chemical forms is essential to characterize its behaviour and the biological impact on the environment. To assess a radionuclide bioavailability to the soil-plant transfer, the chemical forms that are most relevant are the water soluble and exchangeable ones. Laboratory experiments were conducted to determine the potential modifications in time of the Cs-137 distribution in the two soil fractions, induced by the treatment with different K-based fertilizers. The two types of soil were selected taking into account their importance for the agricultural use in Romania. By the sequential extraction method the distribution of 137 Cs has been determined in the water soluble and exchangeable fractions separated from the soils after 1 day, 1 week, 1 month and 4 months, respectively. For the reference untreated soils, experimental data revealed that less than 1 percent of Cs-137 is associated to the water soluble fraction for both types of soil. Around 4 percents of the total amount of Cs-137 in the brown-reddish soil and 13 percents in the alluvial one were associated to the exchangeable fraction. The differences between the Cs-137 distribution are correlated to the higher content of dust and clay in the brown reddish soil, which are strong binders for Cs ions. The application of the two fertilizers releasing fast the K ions (KCl and potassium salt), determined from at the first moment after the contamination a reduction of the Cs-137 concentration in both fraction. The effect was most pronounced for the soluble fraction in the brown -reddish soil: with a factor of 8 in case of KCl treatment and 5 in case of potassium salt. For the others experimental cases the concentration of Cs-137 in both fractions was slightly reduced, with factors between (1

49 CFR 98.10 - Appeal.

Science.gov (United States)

2010-10-01

... Administration of Enforcement Proceedings § 98.10 Appeal. (a) Within 30 working days after receipt of a decision issued under § 98.8 or § 98.9 of this part, either the Departmental counsel or the former employee may appeal the decision to the Secretary. (b) In making a decision on an appeal, the Secretary shall consider...

Diversion of phagosome trafficking by pathogenic Rhodococcus equi depends on mycolic acid chain length.

Science.gov (United States)

Sydor, Tobias; von Bargen, Kristine; Hsu, Fong-Fu; Huth, Gitta; Holst, Otto; Wohlmann, Jens; Becken, Ulrike; Dykstra, Tobias; Söhl, Kristina; Lindner, Buko; Prescott, John F; Schaible, Ulrich E; Utermöhlen, Olaf; Haas, Albert

2013-03-01

Rhodococcus equi is a close relative of Mycobacterium spp. and a facultative intracellular pathogen which arrests phagosome maturation in macrophages before the late endocytic stage. We have screened a transposon mutant library of R. equi for mutants with decreased capability to prevent phagolysosome formation. This screen yielded a mutant in the gene for β-ketoacyl-(acyl carrier protein)-synthase A (KasA), a key enzyme of the long-chain mycolic acid synthesizing FAS-II system. The longest kasA mutant mycolic acid chains were 10 carbon units shorter than those of wild-type bacteria. Coating of non-pathogenic E. coli with purified wild-type trehalose dimycolate reduced phagolysosome formation substantially which was not the case with shorter kasA mutant-derived trehalose dimycolate. The mutant was moderately attenuated in macrophages and in a mouse infection model, but was fully cytotoxic.Whereas loss of KasA is lethal in mycobacteria, R. equi kasA mutant multiplication in broth was normal proving that long-chain mycolic acid compounds are not necessarily required for cellular integrity and viability of the bacteria that typically produce them. This study demonstrates a central role of mycolic acid chain length in diversion of trafficking by R. equi. © 2012 Blackwell Publishing Ltd.

Biological effects of 137Cs, incorporated into organism of rats

International Nuclear Information System (INIS)

Monakhov, A.S.; Strekalov, S.A.; Sokolov, A.V.; Aver'yanova, T.K.

1987-01-01

Results of investigating mutagenous and hemotoxic effects of 137 Cs on blood lymphocytes of rats are presented. 137 Cs was orally administrated into organism of rats as 270 kBq/g chloride solution. 137 Cs mutagenous effect was studied on metaphase plates of rat blood lymphocytes in course of rats lifetime experiment. It is stated that 137 Cs inducing severe disturbances of genetic material in a great quantity of blood lymphocytes, causes their total killing

45 CFR 98.14 - Plan process.

Science.gov (United States)

2010-10-01

... 45 Public Welfare 1 2010-10-01 2010-10-01 false Plan process. 98.14 Section 98.14 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CHILD CARE AND DEVELOPMENT FUND General Application Procedures § 98.14 Plan process. In the development of each Plan, as required pursuant to § 98.17...

The effect of clinoptilolite on 137 Cs binding in broiler chickens

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G. VITOROVIC

2008-12-01

Full Text Available The objective of this study was to evaluate the 137 Cs binding capacity of clinoptilolite.In the first in vitro experiment we investigated sorption of 137 Cs to natural and modified forms of clinoptilolite in highly acid solution,prepared to be similar to that of the gut of pigs (pH =2 3at 37 ºC.In the second in vivo experiment 137 Cs binding to a modified form of clinoptilolite was studied in orally contaminated broiler chickens.137 Cs sorption in the high acidity solution depended on clinoptilolite concentration and varied between 30 85 %of the initial activity.In the chickens,three hours after 137 Cs administration,there was 67%and 63%lower accumulation of 137 Cs in meat and edible organs (respectivelyand seven hours after 137 Cs administration,there was 69% and 49% lower accumulation of 137 Cs in meat and edible organs (respectivelycompared to the controls with no clinoptilolite added in food. Natural and modified forms of clinoptilolite have been shown to high sorption efficiency towards 137 Cs ions and could be recommended as possible radiocaesium binders in domestic animals.;

137Cs use in estimating soil erosion: 30 years of research

International Nuclear Information System (INIS)

Ritchie, J.C.

1998-01-01

Significant amounts of fallout 137 Cs from nuclear weapons tests were introduced to the landscape during the 1950s and 1960s. Once 137 Cs reaches the soil surface it is strongly and quickly adsorbed by clay particles, and is essentially nonexchangeable in most environments. Thus, 137 Cs becomes and effective tracer of the movement of soil particles across the landscape. Over the past 30 years, researchers have shown that 137 Cs can be used to study soil movement. Early work used empirical relationships between soil loss and 137 Cs loss to estimate erosion. This was followed by the development of proportional and theoretical models to relate 137 Cs movement and soil redistribution. Most of the problems related to the 137 Cs technique are the same as those encountered with other techniques (i.e., sampling, measurement). The 137 Cs technique can make actual measurements of soil loss and redeposition in fields, fostering the formulation of better plans to conserve the quality of the landscape. This paper reviews the development of the 137 Cs technique to show how it can be used to understand erosion and soil movement on the landscape. (author)

Behaviour of 137Cs in the Boreal forest ecosystem of central Sweden

International Nuclear Information System (INIS)

Fawaris, B.H.

1995-01-01

Behaviour of Chernobyl fallout 1 37 Cs in a coniferous forest ecosystem in central Sweden was investigated between 1990 and 1994. Results demonstrated that forest soil belongs to nutrient deficient type, and deposited fallout 1 37 Cs from Chernobyl nuclear accident (CNA) was retained (85%) in the upper 5 cm of humic forest soil layer, with a venial migration deeper into soil profile. No correlation between forest soil exchangeable and total potassium (K + ) and 1 37 Cs transfer parameters was observed. However, addition of K + , found to efficiently reduce 1 37 Cs uptake by sheep's fescue and the addition of stable caesium (1 33 Cs + ) enhanced it. The addition of ammonium (NH 4 + ) was slightly stimulating the uptake of 1 37 Cs by sheep's fescue in the first cut only. Field plants showed a considerably reduction in their 1 37 Cs activity concentrations. Relative to their 1 37 Cs levels of 1986-89, a little reduction in heather (16%) occurred eight years after CNA. In contrast the reductions in lingonberry and bilberry were 87% and 68%, respectively. Three fractions of forest soil bound 1 37 Cs were observed due to sequential extraction procedure (SEP). The first, is easily extractable 1 37 Cs fraction (F1+F2), it comprises 22% of total forest soil 1 37 Cs inventory in the upper 5 cm layer. The second, is soil organically and biologically bound 1 37 Cs (F3+F4) comprises about 30% of soil bound 1 37 Cs. This fraction might be accounted for long-term soil available 1 37 Cs for plant uptake after bio-degradation processes by soil microorganisms. The third, is the residual fraction (F5), it comprises more than 35% of total forest soil 1 37 Cs inventory, and may be associated with soil components which are probably of organic nature. Sorption of 1 37 Cs by zeolite (Mordenite) revealed that soil bound 1 37 Cs is to some extent more mobile in forest soils with high OM% and low pH than those with low OM%. 99 refs

Study of 137Cs absorption by Lemna minor

International Nuclear Information System (INIS)

Bergamini, P.G.; Palmas, G.; Piantelli, F.; Sani, M.; Banditelli, P.; Previtera, M.; Sodi, F.

1979-01-01

Absorption of 137 Cs by the floating aquatic plant Lemna Minor in relation to 137 Cs concentration in the water was measured under controlled conditions of temperature, pH and light. The method used to analyse the results is described. When applied to this study the method shows the influence on 137 Cs absorption of (1) potassium-cesium exchange due to chemical affinity, (2) the natural colony growth of the organism and (3) the effect of light. Concentration factors were determined for these three processes. (author)

Radioactive caesium (134Cs and 137Cs) in mushrooms of the genus Boletus from the Reggio Emilia in Italy and Pomerania in Poland.

Science.gov (United States)

Cocchi, Luigi; Kluza, Karolina; Zalewska, Tamara; Apanel, Anna; Falandysz, Jerzy

2017-12-01

Activity concentrations of 134 Cs and 137 Cs were determined in mushrooms of the Boletus species B. aereus, B. reticulatus, B. appendiculatus, B. calopus, B. edulis, B. erythropus, B. fechtneri, B. pinophilus, B. pseudoregius, B. rhodopurpureus, B. rhodoxanthus collected in the Reggio Emilia, Italy, in 1993 and 1994 and in B. edulis collected in Pomerania in northern Poland in the period from 1995-2015. Boletus edulis from the Reggio Emilia showed presence of 137 Cs at 330 ± 220 Bq kg -1 dry biomass in 1993 and at 370 ± 180 Bq kg -1 dry biomass in 1994. In B. edulis sampled in the Reggio Emilia in 1993 and 1994, the pre-Chernobyl 137 Cs from global fallout amounted to 39-46 % of the total activity concentrations of isotope 137 Cs. B. edulis from Pomerania contained 137 Cs in caps at 270 ± 15 Bq kg -1 dry biomass in 1995, and in whole fruiting bodies it was found to be 470 ± 9 Bq kg -1 dry biomass in 2015. The activity concentrations of 137 Cs determined in fruiting bodies of B. edulis from Pomerania fluctuated but persisted over the period from 1995 to 2015, while the maximum activity concentrations were well below the tolerance limit of 600 Bq kg -1 fresh product.

Five years of monitoring Cs-137 And Cs-134 in moss and soil samples in the campania region of Italy after the Chernobyl accident

International Nuclear Information System (INIS)

Fontana, C.; Tenero, A.Lo; Musumeci, R.G.; Valeriani, F.

2000-01-01

The Central Laboratory of The Italian Red Cross is part of the National Network for the Monitoring of the Environmental Radioactivity in Italy, coordinated by the National Environmental Agency (ANPA). The Central Laboratory took part in the national campaigns for the monitoring of the environmental gamma radioactivity in order to evaluate the deposition of artificial radioactivity on Italian territory after the Chernobyl accident. The distribution of the concentration of artificial radionuclide Cs-137 as reached, in North and Central Italy, the higher values: 2-185 kBq/m 2 and 0-40 kBq/m 2 . This paper presents the data of the concentration of artificial radionuclides Cs-137 and Cs-134 in mosses picked up in four different locations in the Campania Region of Italy with the help of the Department of the State Forestry Corp of S.Gregorio Matese, Vesuvio, Laviano, Piaggine from 1993 to 1998. The deposition of artificial radioactivity on the territory expected after the Chernobyl fallout was evaluated. The content of K-40 was also measured. Soil samples were also taken from the same sites. In this study Hypnum cupressiforme and Homalotecium lutescens mosses were used as bioindicators, available in all Italian ecosystems. The soil and moss samples were gathered according to a national standard procedure. These results, obtained by gamma spectrometry analyses, initially have shown values of medium concentration in mosses in the Campania Region of Cs-137 of 375 Bq/m 2 and of Cs-134 of 16 Bq/m 2 and K-40 of 150 Bq/m 2 in line with the ones of other Italian regions. The results of the average concentrations of the Cs-137 and Cs-134 in the mosses confirm a uniform distribution of post-Chernobyl radioactivity in the regional territory, in the Department of the State Forestry Corp of Vesuvio, Laviano and Piaggine. The results of Cs-137 and Cs-134 of S.Gregorio Matese are in accordance with the previous data relative to the monitoring campaign of mosses in Italy from 1992 to

Analysis on the influence of forest soil characteristics on radioactive Cs infiltration and evaluation of residual radioactive Cs on surfaces.

Science.gov (United States)

Mori, Yoshitomo; Yoneda, Minoru; Shimada, Yoko; Fukutani, Satoshi; Ikegami, Maiko; Shimomura, Ryohei

2018-03-29

We investigated the depth profiles of radioactive Cs, ignition loss, and cation exchange capacity (CEC) in five types of forest soils sampled using scraper plates. We then simulated the monitored depth profiles in a compartment model, taking ignition loss as a parameter based on experimental results showing a positive correlation between ignition loss and the CEC. The calculated values were comparable with the monitored values, though some discrepancy was observed in the middle of the soil layer. Based on decontamination data on the surface dose rate and surface contamination concentration, we newly defined a surface residual index (SRI) to evaluate the residual radioactive Cs on surfaces. The SRI value tended to gradually decrease in forests and unpaved roads and was much smaller in forests and on unpaved roads than on paved roads. The radioactive Cs was assumed to have already infiltrated underground 18 months after the nuclear power plant accident, and the sinking was assumed to be ongoing. The SRI values measured on paved roads suggested that radioactive Cs remained on the surfaces, though a gradual infiltration was observed towards the end of the monitoring term. The SRI value is thought to be effective in grasping the rough condition of residual radioactive Cs quickly at sites of decontamination activity in the field. The SRI value may be serviceable for actual contamination works after further research is done to elucidate points such as the relation between the SRI and the infiltration of radioactive Cs in various types of objects.

Cs-137 and Sr-90 level in diary products

International Nuclear Information System (INIS)

Petukhov, V.L.; Dukhanov, Y.A.; Sevryuk, I.Z.; Patrashkov, S.A.; Korotkevich, O.S.; Gorb, T.S.; Petukhov, I.V.

2003-01-01

About 70% of radioactive substances fell on the territory of the Byelorussian Republic after the Chernobyl Atom Power Station Disaster. Cs-137 and Sr-90 accumulation dynamics was studied in milk of the cows from the highest polluted Braginsky area. 408 milk samples of Black and White cows were investigated. In 1995 average Cs-137 and Sr-90 levels were 61.00 and 3.73 Bk/dm 3 respectively. Cs-137 and Sr-90 levels exceeded Byelorussian Republic upper limits RDU - 96 in 10 and 50% of milk samples respectively. After 5 years (by 2000) Cs-137 and Sr-90 levels had become almost 3 and 2 times less (21.70 Bk/dm 3 and 1.72 Bk/dm 3 respectively). Cs-137 and Sr-90 levels exceeded RDU - 96 in 1.5 and 5.5% of milk samples respectively. In the same periods Cs-137 and Sr-90 levels were 7 and 2 times higher than the similar indexes in the relatively clean Novosibirsk area. Thus, radioactive element levels in milk of Black and White cows of the Byelorussian Republic decreased significantly for the past years. (authors)

Photoelectron Emission Studies in CsBr at 257 nm

International Nuclear Information System (INIS)

Maldonado, Juan R.; Liu, Zhi; Sun, Yun; Pianetta, Piero A.; Pease, Fabian W.

2006-01-01

CsBr/Cr photocathodes were found [1,2] to meet the requirements of a multi-electron beam lithography system operating with a light energy of 4.8 eV (257nm). The fact that photoemission was observed with a light energy below the reported 7.3 eV band gap for CsBr was not understood. This paper presents experimental results on the presence of intra-band gap absorption sites (IBAS) in CsBr thin film photo electron emitters, and presents a model based on IBAS to explain the observed photoelectron emission behavior at energies below band gap. A fluorescence band centered at 330 nm with a FWHM of about 0.34 eV was observed in CsBr/Cr samples under 257 nm laser illumination which can be attributed to IBAS and agrees well with previously obtained synchrotron photoelectron spectra[1] from the valence band of CsBr films

Knudsen cell mass spectrometric study of the Cs2IOH(g) molecule thermodynamics

International Nuclear Information System (INIS)

Roki, F-Z.; Ohnet, M-N.; Fillet, S.; Chatillon, C.; Nuta, I.

2013-01-01

Highlights: • The pronounced ionic character leads to only dissociative ionization processes. • Ions formed are same as those coming from pure dimmers. • De-convolution of the ions origin needs accurate thermodynamic values for the pure gas phase. • Mass spectrometric interpretation has to be performed gradually and as a function of suitable condensed compositions. • Thermal functions have to be fully estimated. -- Abstract: The gas phase of the CsI + CsOH system is analyzed by high temperature Knudsen cell mass spectrometry in order to confirm the existence of the Cs 2 IOH(g) complex molecule. The mass spectrometric analysis is quite complex since such molecules undergo dissociative ionization into fragment ions that mix with the same ions from dimers of the pure compounds in the same vapor phase. Varying the chemical conditions for vaporization by using different CsI + CsOH mixture contents showed that the ionization of the Cs 2 IOH(g) molecule led to five different fragment ions, Cs 2 OH + , Cs 2 I + , Cs + , CsOH + and CsI + . This complex ionization pattern was studied in relation with previous assessed values for the vaporization of CsOH and CsI pure compounds in which monomer and dimer molecules are predominant. The equilibrium constant for the reaction CsI(g) + CsOH(g) = Cs 2 IOH(g) was determined and, after modeling the structure of the Cs 2 IOH molecule, the enthalpy of formation was determined using the third law of thermodynamics, as follows: Δ f H°(Cs 2 IOH, g, 298.15 K) = −578 ± 14.7 kJ · mole −1

Retention of 137Cs in three humans

International Nuclear Information System (INIS)

Soegaard-Hansen, J.; Lauridsen, B.

1992-01-01

In two experiments the retention of 137 Cs after a single intake have been measured with whole-body counting. In the first experiment, two persons ingested a prepared liquid solution of 137 CsCl. In the second experiment these two persons together with a third person ingested 137 Cs naturally incorporated in a piece of meat. The obtained data have been fitted to a retention function with a small compartment having a fast excretion rate and a large compartment having a slow excretion rate, as given by the International Commission on Radiological Protection (ICRP). The effective biological half-lives were in both experiments significantly different from the value given by ICRP. (au)

Cs-137 for irradiation of sewage sludge

International Nuclear Information System (INIS)

Lessel, T.

1986-01-01

Since 1973, the Geiselbullach sewage treatment works have been continuously operating their first system for gamma irradiation of sewage sludge. Within the framework of a German-American agreement, nine Cs-137 sources with a total activity of 56.000 Ci have been made available to the works free of charge in 1983, in order to test in practice and to demonstrate the applicability of these radiation sources in comparison to the Co-60 sources exclusively used up to then. This first study on the applicability of Cs-137 as a radiation source for sewage sludge treatment revealed no findings or effects speaking against Cs-137 as a radiation source for this purpose. (orig./RB) [de

Accumulation of a poly(hydroxyalkanoate) copolymer containing primarily 3-hydroxyvalerate from simple carbohydrate substrates by Rhodococcus sp. NCIMB 40126.

Science.gov (United States)

Haywood, G W; Anderson, A J; Williams, D R; Dawes, E A; Ewing, D F

1991-04-01

A number of taxonomically-related bacteria have been identified which accumulate poly(hydroxyalkanoate) (PHA) copolymers containing primarily 3-hydroxyvalerate (3HV) monomer units from a range of unrelated single carbon sources. One of these, Rhodococcus sp. NCIMB 40126, was further investigated and shown to produce a copolymer containing 75 mol% 3HV and 25 mol% 3-hydroxybutyrate (3HB) from glucose as sole carbon source. Polyesters containing both 3HV and 3HB monomer units, together with 4-hydroxybutyrate (4HB), 5-hydroxyvalerate (5HV) or 3-hydroxyhexanoate (3HHx), were also produced by this organism from certain accumulation substrates. With valeric acid as substrate, almost pure (99 mol% 3HV) poly(3-hydroxyvalerate) was produced. N.m.r. analysis confirmed the composition of these polyesters. The thermal properties and molecular weight of the copolymer produced from glucose were comparable to those of PHB produced by Alcaligenes eutrophus.

Speciation of 137Cs in the Baltic sea water

International Nuclear Information System (INIS)

Lujaniene, G.; Morkuniene, R.; Styra, D.

1998-01-01

A possibility of application of Filtrac 391 and Nuclepore filters, Ky-2-8-C exchanger and the Mtilon-T fiber impregnated with Fe, Co, Ni ferrocyanides for separation of particulate and ionic 137 Cs in the sea water was investigated. Physico-chemical forms of 137 Cs were investigated in the Baltic Sea water during 1995-1997. It was determined that 137 Cs was mainly present in ionic form (62-93 %) both in the near-shore and open waters. Concentration of particulate 137 Cs ranged from 255 to 625 Bq/kg (dry weight).The distribution coefficient (K d ) of radiocaesium reached values of 2100-9700. (author)

Elastic properties of Cs2HgBr4 and Cs2CdBr4 crystals

International Nuclear Information System (INIS)

Kityk, A.V.; Zadorozhna, A.V.; Shchur, Y.I.; Martynyuk-Lototska, Y.I.; Burak, Y.; Vlokh, O.G.

1998-01-01

Using ultrasonic velocity measurements, all components of the elastic constant matrix C ij , elastic compliances matrix S ij , and linear compressibility constants matrix K ij of orthorhombic Cs 2 HgBr 4 and Cs 2 CdBr 4 crystals have been determined over a wide temperature range, including the region of the phase transition from the normal to the incommensurate phase. Results obtained are considered within the framework of the phenomenological theory. Preliminary analysis of the acoustical properties at room temperature clearly indicates that both crystals are relatively important materials for acousto-optical applications. Copyright (1998) CSIRO Australia

Energy transfer mechanism in CsI:Eu crystal

International Nuclear Information System (INIS)

Yakovlev, V.; Trefilova, L.; Karnaukhova, A.; Ovcharenko, N.

2014-01-01

This paper studies the scintillation process in CsI:Eu crystal exposed to the pulse electron irradiation (E=0.25 MeV, t 1/2 =15 ns and W=0.003 J/cm 2 ). It has been proved that the energy transfer from the lattice to Eu 2+ ions in CsI:Eu occurs through the re-absorption of STE emission. The proposed model rests on the following experimental facts: (1) the activator emission at 2.68 eV rises gradually after the decay of the excitation pulse even at temperature lower than 90 K when V k centers are immobile; (2) the rise time of 2.68 eV emission and the decay time of STE emission have the same temperature dependences at T=78–300 K; (3) the excitation spectrum of 2.68 eV emission overlaps the emission spectrum of STE. -- Highlights: • The scintillation process in CsI:Eu was studied under pulsed electron irradiation. • A model of the energy transfer from the lattice to Eu 2+ ions in CsI:Eu was proposed. • Eu 2+ ions in CsI:Eu reabsorb the π-emission of self-trapped excitons

New crystals of the CsHSO{sub 4}–CsH{sub 2}PO{sub 4}–H{sub 2}O system

Energy Technology Data Exchange (ETDEWEB)

Makarova, I. P., E-mail: makarova@crys.ras.ru; Grebenev, V. V.; Komornikov, V. A.; Selezneva, E. V. [Russian Academy of Sciences, Shubnikov Institute of Crystallography, Federal Scientific Research Centre “Crystallography and Photonics,” (Russian Federation)

2016-11-15

Cs{sub 6}H(HSO{sub 4}){sub 3}(H{sub 2}PO{sub 4}){sub 4} crystals, grown for the first time based on an analysis of the phase diagram of the CsHSO{sub 4}–CsH{sub 2}PO{sub 4}–H{sub 2}O ternary system, have been investigated by structural analysis using synchrotron radiation. The atomic structure of the crystals is determined and its specific features are analyzed.

Sorption Analysis of 137Cs On Karawang’s Clay Samples

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Budi Setiawan

2016-12-01

Full Text Available The objective of this work is to characterize the specific of distribution coefficient (Kd values of 137Cs onto Karawang’s clay for radioactive waste disposal facility purpose. Sorption phenomena was affected by contact time, ionic strength and loaded concentration of CsCl.  Experiments were done in a batch method, with initial concentration was 10-8 M CsCl in the experiments of contact time and ionic strength effects. In the CsCl loading experiment, the concentration was varied from 10-8 to 10-4 M CsCl and 137Cs radioactive solution was used as a tracer. The solid-liquid ratio is 10-2 g/mL.  The results shown that obtained Kd values were 21,714 and 4035 mL/g after contacted for 8 days for Sample-1 and 2, respectively. The presence of K+ and Na+ ions in solution had reduced the Kd value Cs-137 where the effect of K+ is greater than Na+ on decreased the value of Kd.  The increasing of CsCl concentrations in solution had reduced the value of Kd.  In both samples of clay were closely fit to Freundlich isotherm and pseudo-second order kinetic model.  The results are very useful as the input of the safety assessment activity of site candidate for radioactive waste disposal facility in the future.

A homeostatic-partly dynamic model for 137Cs in trees

International Nuclear Information System (INIS)

Frissel, M.

1994-01-01

A model has been developed to describe the behaviour of 137 Cs in trees. The core of the model is the assumption that 137 Cs/K ratio in soil determines the 137 Cs/K ratio in various parts of a tree. This is an equilibrium model but taking into account the time dependence of Cs/K ratio in the soil (caused by K-fertilization) it has been extended to a dynamic model. The model desribes a growing tree. Four compartments are considered: soil; easily accessible parts of the tree; woody parts difficult to access; fruits or leaves. The model is homeostatic, i.e. all 137 Cs concentrations and fluxes are controlled by K concentrations and fluxes, respectively. The addition of K-fertilizer to the soil manifests itself in an immediate change of the Cs/K ratio in the soil and in the easily accessible plant parts, but only slowly - in the woody parts. Also an excess of Cs in the woody part is only slowly released. Important processes are the discrimination between Cs and K and the luxurious consumption of K. The cycling of K in the system (throughput of K via falling leaves, branches, etc.) is also important. Furthermore, a good insight in accessibility of the various parts of the tree seems required, the division in only three compartments, as in the model is probably unsufficient. (author)

Paddy-field contamination with 134Cs and 137Cs due to Fukushima Dai-ichi Nuclear Power Plant accident and soil-to-rice transfer coefficients

International Nuclear Information System (INIS)

Endo, Satoru; Kajimoto, Tsuyoshi; Shizuma, Kiyoshi

2013-01-01

The transfer coefficient (TF) from soil to rice plants of 134 Cs and 137 Cs in the form of radioactive deposition from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in March 2011 was investigated in three rice paddy fields in Minami-Soma City. Rice crops were planted in the following May and harvested at the end of September. Soil cores of 30-cm depth were sampled from rice-planted paddy fields to measure 134 Cs and 137 Cs radioactivity at 5-cm intervals. 134 Cs and 137 Cs radioactivity was also measured in rice ears (rice with chaff), straws and roots. The rice ears were subdivided into chaff, brown rice, polished rice and rice bran, and the 134 Cs and 137 Cs radioactivity concentration of each plant part was measured to calculate the respective TF from the soil. The TF of roots was highest at 0.48 ± 0.10 in the field where the 40 K concentration in the soil core was relatively low, in comparison with TF values of 0.31 and 0.38 in other fields. Similar trends could be found for the TF of whole rice plants, excluding roots. The TF of rice ears was relatively low at 0.019–0.026. The TF of chaff, rice bran, brown rice and polished rice was estimated to be 0.049, 0.10–0.16, 0.013–0.017 and 0.005–0.013, respectively. - Highlights: ► We investigated the transfer coefficient of 134 Cs and 137 Cs from soil to rice plants in Minami-Soma City due to the Fukushima accident in 2011. ► The rice ears, straws, roots, chaff, brown rice, polished rice, rice bran and soil samples have been measured by Ge-detector. ► Transfer coefficient of chaff, rice bran, brown rice, and polished rice is estimated as 0.049, ranging from 0.10 to 0.16, 0.013 to 0.017, and 0.005 to 0.013, respectively.

Physicochemical properties of the CsNO2-CsOH-H2O ternary system at 25 deg C

International Nuclear Information System (INIS)

Protsenko, P.I.; Medvedev, B.S.; Popova, T.B.

1977-01-01

Saturated solutions of the CsNO 2 - CsOH- H 2 O system have been studied at 25 deg C by the methods of solubility, viscosity, electric conductivity, refractometry and density. It is stated that no solid phase of a new composition is formed in the system. While adding hydroxide to the saturated solution of cesium nitride, a considerable salting-out of the latter takes place

Water-resistant, monodispersed and stably luminescent CsPbBr3/CsPb2Br5 core-shell-like structure lead halide perovskite nanocrystals

Science.gov (United States)

Qiao, Bo; Song, Pengjie; Cao, Jingyue; Zhao, Suling; Shen, Zhaohui; Gao, Di; Liang, Zhiqin; Xu, Zheng; Song, Dandan; Xu, Xurong

2017-11-01

Lead halide perovskite materials are thriving in optoelectronic applications due to their excellent properties, while their instability due to the fact that they are easily hydrolyzed is still a bottleneck for their potential application. In this work, water-resistant, monodispersed and stably luminescent cesium lead bromine perovskite nanocrystals coated with CsPb2Br5 were obtained using a modified non-stoichiometric solution-phase method. CsPb2Br5 2D layers were coated on the surface of CsPbBr3 nanocrystals and formed a core-shell-like structure in the synthetic processes. The stability of the luminescence of the CsPbBr3 nanocrystals in water and ethanol atmosphere was greatly enhanced by the photoluminescence-inactive CsPb2Br5 coating with a wide bandgap. The water-stable enhanced nanocrystals are suitable for long-term stable optoelectronic applications in the atmosphere.

Crystal Growth and Scintillation Properties of Eu2+ doped Cs4CaI6 and Cs4SrI6

Science.gov (United States)

Stand, L.; Zhuravleva, M.; Chakoumakos, B.; Johnson, J.; Loyd, M.; Wu, Y.; Koschan, M.; Melcher, C. L.

2018-03-01

In this work we present the crystal growth and scintillation properties of two new ternarymetal halide scintillators activated with divalent europium, Cs4CaI6 and Cs4SrI6. Single crystals of each compound were grown in evacuated quartz ampoules via the vertical Bridgman technique using a two-zone transparent furnace. Single crystal X-ray diffraction experiments showed that both crystals have a trigonal (R-3c) structure, with a density of 3.99 g/cm3 and 4.03 g/cm3. The radioluminescence and photoluminescence measurements showed typical luminescence properties due to the 5d-4f radiative transitions in Eu2+. At this early stage of development Cs4SrI6:Eu and Cs4CaI6:Eu have shown very promising scintillation properties, with light yields and energy resolutions of 62,300 ph/MeV and 3.3%, and 51,800 photons/MeV and 3.6% at 662 keV, respectively.

{sup 137}Cs applicability to soil erosion assessment: theoretical and empirical model; Aplicabilidade do {sup 137}Cs para medir erosao do solo: modelos teoricos e empiricos

Energy Technology Data Exchange (ETDEWEB)

Andrello, Avacir Casanova

2004-02-15

The soil erosion processes acceleration and the increase of soil erosion rates due to anthropogenic perturbation in soil-weather-vegetation equilibrium has influenced in the soil quality and environment. So, the possibility to assess the amplitude and severity of soil erosion impact on the productivity and quality of soil is important so local scale as regional and global scale. Several models have been developed to assess the soil erosion so qualitative as quantitatively. {sup 137}Cs, an anthropogenic radionuclide, have been very used to assess the superficial soil erosion process Empirical and theoretical models were developed on the basis of {sup 137} Cs redistribution as indicative of soil movement by erosive process These models incorporate many parameters that can influence in the soil erosion rates quantification by {sup 137} Cs redistribution. Statistical analysis was realized on the models recommended by IAEA to determinate the influence that each parameter generates in results of the soil redistribution. It was verified that the most important parameter is the {sup 137} Cs redistribution, indicating the necessity of a good determination in the {sup 137} Cs inventory values with a minimum deviation associated with these values. After this, it was associated a 10% deviation in the reference value of {sup 137} Cs inventory and the 5% in the {sup 137} Cs inventory of the sample and was determinate the deviation in results of the soil redistribution calculated by models. The results of soil redistribution was compared to verify if there was difference between the models, but there was not difference in the results determinate by models, unless above 70% of {sup 137} Cs loss. Analyzing three native forests and an area of the undisturbed pasture in the Londrina region, can be verified that the {sup 137} Cs spatial variability in local scale was 15%. Comparing the {sup 137} Cs inventory values determinate in the three native forest with the {sup 137} Cs inventory

Transfer of 137Cs through the food chain to man

International Nuclear Information System (INIS)

Evans, C.; Bennett, B.G.

1976-10-01

Deposition, concentrations in diet, and body burdens of 137 Cs have been measured since 1954 at various sites throughout the world. This report is a compilation and updating of various fallout 137 Cs measurements and an interpretation of transfer properties of 137 Cs from deposition to diet and from diet to man. An empirical model is used to correlate deposition and diet data. Direct foliar contamination, stored food supplies, and uptake from soil contribute to the dietary levels of 137 Cs. The accumulation of 137 Cs by man is described by a single exponential model. The inferred biological half-times, 200 to 400 days, are somewhat greater than the half-time of about 100 days obtained from shorter term studies. Differences in body burdens due to sex, age, and weight are discussed. During the period 1954 to 1974, the internal dose from fallout 137 Cs, based on average body burdens, is estimated to be 4 to 5 percent of the 21 year radiation dose from 40 K

Shape and phase evolution from CsPbBr3 perovskite nanocubes to tetragonal CsPb2Br5 nanosheets with an indirect bandgap.

Science.gov (United States)

Li, Guopeng; Wang, Hui; Zhu, Zhifeng; Chang, Yajing; Zhang, Ting; Song, Zihang; Jiang, Yang

2016-09-13

Tetragonal CsPb 2 Br 5 nanosheets were obtained by an oriented attachment of orthorhombic CsPbBr 3 nanocubes, involving a lateral shape evolution from octagonal to square. Meanwhile, the experimental results, together with DFT simulation results, indicated that the tetragonal CsPb 2 Br 5 is an indirect bandgap semiconductor that is PL-inactive with a bandgap of 2.979 eV.

Radioecological studies of 137Cs in limnological ecosystems. 137Cs concentrations in water, sediment and biota at the lower region of the famous river in Saitama Prefecture

International Nuclear Information System (INIS)

Miyake, Sadaaki; Motegi, Misako; Oosawa, Takashi; Nakazawa, Kiyoaki; Ogata, Hiromitsu; Izumo, Yoshiro; Nakamura, Fumio.

1996-01-01

The concentrations of 137 Cs in water, sediment and biota at the lower region of the famous river in Saitama prefecture were determined in order to elucidate the radioecology of 137 Cs in limnological ecosystems. 137 Cs concentration in water was 0.10 mBq/l. 137 Cs concentrations in sediment, shellfish, Sinotaia quadratus historica (mean for 2 detectable samples), and fish, Carassius auratus cuvieri (mean for 2 detectable samples), were about 6200, 840 and 320 times higher than the concentration of the water, respectively. But 137 Cs radioactivity in the crustacea, Procambarus clarki, was significantly not detected. So, 137 Cs transfer mechanism in the limnological ecosystems was indicated in part. (author)

CS Bond formation by

Indian Academy of Sciences (India)

2017-02-02

Feb 2, 2017 ... a thiol substituent at position-2 of the quinazoline ring. ... coupling reactions represent great contribution to the recent growth of organic synthesis.2 ... Difficulties in C-S ...... Experimental Advances (Amsterdam: Elsevier) 19; (b).

Disseminated Rhodococcus equi infection in a patient with Hodgkin’s lymphoma

Directory of Open Access Journals (Sweden)

Mikić Dragan

2014-01-01

Full Text Available Introduction. Rhodococcus (R equi is an opportunistic, uncommon human pathogen that causes mainly infection in immunocompromised hosts. The disease is usually presented as subacute pneumonia that is mostly cavitary and sometimes bacteremic. Case report. We reported the extremly rare case of a 43-year-old woman with Hodgkin's lymphoma, who developed R. equi pulmonary infection after recieving multiple courses of chemotherapy. Secondary, the patient developed bacteremia, leading to sepsis and dissemination of R. equi infection in many extrapulmonary sites. At addmission the patient was febrile, tachypnoic, tachycardic, hypotensive, with facial edema, splenomegaly, positive meningeal signs, left hemiparesis and paraparesis. Laboratory data included erythrocyte sedimentation rate (ESR > 140 mm/h, C-reactive protein (CRP 143.0 mg/L, red blood cells (RBC 2.14 × 1012/L, whyite blood cells (WBC 2.8 × 109/L, lactate dehydrogenase (LDH 706 U/L, serum albumin 26 g/L, sodium 127 mmol/L and potassium 2.7 mmol/L. Blood culture and culture of sputum and empyema were positive for R. equi. Imaging studies demonstrated a large right cavitary pneumonia and abscess, empyema, pericarditis, mediastinal and intra-abdominal lymphadenopathy, brain and psoas abscesses, osteomyelitis and spondylodiscitis. The patient recovered completely after a 12-month treatment with combinations of parenteral and oral antibiotics (meropenem, vancomycin, teicoplanin, ciprofloxacin, rifampicin, macrolides etc, including drainage of abscesses and empyema. Eight years after completition of the treatment the patient was without recurrence of R. equi infection and lymphoma. Conclusion. Since the eradication od R. equi is very difficult, it is very important to make the diagnosis and initiate appropriate antibiotic therapy as soon as possible.

Recent 210Pb, 137Cs and 241Am accumulation in an ombrotrophic peatland from Amsterdam Island (Southern Indian Ocean).

Science.gov (United States)

Li, Chuxian; Le Roux, Gaël; Sonke, Jeroen; van Beek, Pieter; Souhaut, Marc; Van der Putten, Nathalie; De Vleeschouwer, François

2017-09-01

Over the past 50 years, 210 Pb, 137 Cs and 241 Am have been abundantly used in reconstructing recent sediment and peat chronologies. The study of global aerosol-climate interaction is also partially depending on our understanding of 222 Rn- 210 Pb cycling, as radionuclides are useful aerosol tracers. However, in comparison with the Northern Hemisphere, few data are available for these radionuclides in the Southern Hemisphere, especially in the South Indian Ocean. A peat core was collected in an ombrotrophic peatland from the remote Amsterdam Island (AMS) and was analyzed for 210 Pb, 137 Cs and 241 Am radionuclides using an underground ultra-low background gamma spectrometer. The 210 Pb Constant Rate of Supply (CRS) model of peat accumulations is validated by peaks of artificial radionuclides ( 137 Cs and 241 Am) that are related to nuclear weapon tests. We compared the AMS 210 Pb data with an updated 210 Pb deposition database. The 210 Pb flux of 98 ± 6 Bq·m -2 ·y -1 derived from the AMS core agrees with data from Madagascar and South Africa. The elevated flux observed at such a remote location may result from the enhanced 222 Rn activity and frequent rainfall in AMS. This enhanced 222 Rn activity itself may be explained by continental air masses passing over southern Africa and/or Madagascar. The 210 Pb flux at AMS is higher than those derived from cores collected in coastal areas in Argentina and Chile, which are areas dominated by marine westerly winds with low 222 Rn activities. We report a 137 Cs inventory at AMS of 144 ± 13 Bq·m -2 (corrected to 1969). Our data thus contribute to the under-represented data coverage in the mid-latitudes of the Southern Hemisphere. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cucumber Metallothionein-Like 2 (CsMTL2 Exhibits Metal-Binding Properties

Directory of Open Access Journals (Sweden)

Yu Pan

2016-11-01

Full Text Available We identified a novel member of the metallothionein (MT family, Cucumis sativus metallothionein-like 2 (CsMTL2, by screening a young cucumber fruit complementary DNA (cDNA library. The CsMTL2 encodes a putative 77-amino acid Class II MT protein that contains two cysteine (Cys-rich domains separated by a Cys-free spacer region. We found that CsMTL2 expression was regulated by metal stress and was specifically induced by Cd2+ treatment. We investigated the metal-binding characteristics of CsMTL2 and its possible role in the homeostasis and/or detoxification of metals by heterologous overexpression in Escherichia coli cells. Furthermore, we produced a deletion mutant form of the protein, CsMTL2m, that contained the two Cys-rich clusters but lacked the spacer region, in E. coli. We compared the metal-binding properties of CsMTL2 with those of CsMTL2m, the β domain of human metallothionein-like protein 1 (HsMTXb, and phytochelatin-like (PCL heterologously expressed in E. coli using metal-binding assays. We found that E. coli cells expressing CsMTL2 accumulated the highest levels of Zn2+ and Cd2+ of the four transformed cell types, with levels being significantly higher than those of control cells containing empty vector. E. coli cells expressing CsMTL2 had a higher tolerance for cadmium than for zinc ions. These findings show that CsMTL2 improves metal tolerance when heterologously expressed in E. coli. Future studies should examine whether CsMTL2 improves metal tolerance in planta.

Reversible light-mediated compositional and structural transitions between CsPbBr3 and CsPb2Br5 nanosheets.

Science.gov (United States)

Shen, Wei; Ruan, Longfei; Shen, Zhitao; Deng, Zhengtao

2018-03-13

This communication describes a new method to achieve reversible light-induced chemical composition and phase structural transitions from polyvinylpyrrolidone-capped orthorhombic CsPbBr 3 to tetragonal CsPb 2 Br 5 nanosheets or vice versa. This work will deepen our understanding of the controlled synthesis, post-processing, and decomposition pathway of cesium lead halide perovskite nanocrystals.

Contribution of Asian dust to atmospheric deposition of radioactive cesium (137Cs)

International Nuclear Information System (INIS)

Fukuyama, Taijiro; Fujiwara, Hideshi

2008-01-01

Both Asian dust (kosa) transported from the East Asian continent and locally suspended dust near monitoring sites contribute to the observed atmospheric deposition of 137 Cs in Japan. To estimate the relative contribution of these dust phenomena to the total 137 Cs deposition, we monitored weekly deposition of mineral particles and 137 Cs in spring. Deposition of 137 Cs from a single Asian dust event was 62.3 mBq m -2 and accounted for 67% of the total 137 Cs deposition during the entire monitoring period. Furthermore, we found high 137 Cs specific activity in the Asian dust deposition sample. Although local dust events contributed to 137 Cs deposition, their contribution was considerably smaller than that of Asian dust. We conclude that the primary source of atmospheric 137 Cs in Japan is dust transported from the East Asian continent

Mastering Adobe Premiere Pro CS6

CERN Document Server

Ekert, Paul

2013-01-01

Designed to be practical and engaging, Mastering Adobe Premiere Pro CS6 is a project-based book to help you truly augment your skills and become a film editing hotshot.If you're just starting out or even migrating from existing video editing software, then this book is for you. With rapid progression through practical examples constructed to be both engaging and useful, Mastering Adobe Premiere Pro CS6 is ideal for learning the sometimes complex workflows of this powerful application.

{sup 137}CS-determination in game meat from some hunting areas in lower Austria; {sup 137}Cs-Bestimmungen im Wildfleisch aus einigen niederoesterreichischen Jagdrevieren

Energy Technology Data Exchange (ETDEWEB)

Ayromlou, S. [Inst. fuer Anorganische Chemie der Univ. Wien (Austria); Tataruch, F. [Forschungsinstitut fuer Wildtierkunde und Oekologie der Veterinaermedizinischen Univ., Wien (Austria)

2001-07-01

In 1986, the contamination of some regions in Austria by {sup 137}Cs, due to the Chernobyl accident was relatively high. Among other {sup 137}Cs is taken up by people by the consumption of game. In an area of Lower Austria which is relatively heavily contaminated by Chernobyl fallout since 1986 the {sup 137}Cs-contamination of meat of game-animals was measured every year. Clear differences arose in the load of the single game species whose causes just like the temporal changes are discussed. The highest {sup 137}Cs activity concentration was with 5243 Bq/kg measured on a wild boar. With this activity concentration an annual effective dose of only 0,06 mSv can be estimated for an annual average consumption of one kilogram meat of wild boar. (orig.) [German] Druch den Reaktor-Unfall in Tschernobyl wurde Oesterreich gebietsweise relativ stark mit {sup 137}Cs kontaminiert. Unter anderem gelangt {sup 137}Cs durch den Verzehr von Wildfleisch in den Koerper der Menschen. Daher wurden in einem niederoesterreichischen Gebiet, das 1986 durch Fallout verhaeltnismaessig stark kontaminiert worden war seither jaehrlich erlegte Wildtiere auf den {sup 137}Cs-Gehalt ihres Fleisches hin untersucht. Dabei ergaben sich deutliche Unterschiede in der Belastung der einzelnen Wildarten, deren Ursachen ebenso wie die zeitlichen Veraenderungen diskutiert werden. Die hoechste {sup 137}Cs-Aktivitaetskonzentration wurde mit 5243 Bq/kg bei einem Wildschwein gemessen. Mit einen durchschnittlichen Verzehr von 1 kg Wildschweinfleisch pro Jahr kann daraus eine maximale Effektivdosis von nur 0,06 mSv/Jahr abgeschaetzt werden. (orig.)

Relationship between 137Cs concentration and cultivated history on loessial hillslopes

International Nuclear Information System (INIS)

Wang Xiaoyan; Tian Junliang; Yang Mingyi; Liu Puling

2005-01-01

There are close linkages between soil loss degree and soil disturbance degree by human. So it is a key problem to know that how human activity affects soil loss. To analyse the correlation of 137 Cs loss degree with hillslopes' cultivated histories, the concentrations of 137 Cs on different kinds of loessial hillslopes with different cultivated histories, abandoned ages and different patterns of reforestation are studied. The result shows that there is a linear relationship among 137 Cs areal concentrations, cultivation ages and slope gradients. the regressive equation is as follows: X=2356.79-22.77 t-35.53 S. Variant coefficient of 137 Cs areal concentration is 80.11% among hillslopes with different abandonment ages. It is also deduced that 137 Cs areal concentration is affected primarily by abandonment ages of hillslopes. The 137 Cs loss rates of hillslopes with different vegetation restoration manners show significant differences, as a whole, autogenic restoration 137 Cs area concentrations on hillslopes. (authors)

Internal contamination assessment, with regard to 90Sr, 134Cs, and 137Cs nuclei during nuclear accident

International Nuclear Information System (INIS)

Ayad, M.; Hanna, K.M.

2000-01-01

In case of nuclear reactor accident leading to the release of some radioactive isotopes in the plume, the sedimentation of its constituents on the ground causes surface contamination which consequently can be observed in the form of an internal contamination in the living biosphere. The migration of the radio nuclei from the soil to the plant root, stem, and the other edible parts is considered the main source for the contaminated foodstuffs used by the general public. In this work we have calculated the total accumulative internal dose for 9 0Sr, 1 34Cs, and 1 37Cs radio contaminants with regard to different public age groups (infant, child, and adult) due to an unexpected nuclear accident. In our calculations we have applied the protective measure inequality for the chosen standard group of foodstuffs, with respect to each age group of the public as well as the three indicated above radio nuclei. Our results indicated that the values of the calculated protective measures with regard to 9 0Sr, 1 37Cs, and 1 34Cs radio nuclei are increasing respectively for all age groups. In addition, we found that the ratio of the total protection measure values of all radio nuclei for different age groups still less than one which requires no intervention level procedures

Direct and indirect contamination of tree crops with Cs-134

International Nuclear Information System (INIS)

Skarlou, V.; Nobeli, C.; Anoussis, J.; Arapis, G.; Haidouti, C.

1996-01-01

A long term glasshouse pot experiment was established in 1994 to study the transfer factors of Cs-134 from soil to olive and orange trees for which no relevant data are available. A calcareous-heavy textured and an acid-light textured soil were used in this experiment. Results from two year's experimentation are considered in this study. The ability of the studied plant species for Cs-134 root uptake seems to be significantly influenced by soil type. The contamination of both tree species grown on calcareous and heavy soil was very low and did not change much with the time. On the contrary, trees grown on acid and light soil showed much higher Cs-134 concentration (up to 34 times for orange and 23 for olive trees) which significantly increased with the time. Both olive and orange trees showed a similar behaviour in the studied soils. Effort was also made to study the long term consequences of the direct contamination in a field experiment where an olive tree was contaminated by dry deposition with Cs-134. Six months after contamination 5 % of the Cs-134 deposited on the leaves was measured in the first olive production. However, very small quantities (= 0.5 %) of the olive Cs-134 was detected in the unprocessed olive oil. The following year 15 % of the Cs-134 remained in the leaves while extremely low quantities of Cs-134 were detected in either olives or olive oil. (author)

Changes in 137Cs transfer to agricultural products

International Nuclear Information System (INIS)

Goncharov, N.; Timochtchenko, A.; Milutin, A.

1999-01-01

The food production and food harvesting systems common in the areas contaminated by the Chernobyl accident in Republic of Belarus can be grouped into three major categories: collective farm produce, private farming produce and natural foods collected from natural ecosystems. The collective farm system provided the smallest contribution (8-12 %) to the intake of 137 Cs. Natural food was the major contributor to the intake at one study site (73 %), and private produce was the major contributor (60 %) at the other study site. Assessment of the situation just after the accident (one year) shows that collective farming was still a minor contributor to 137 CS intake (10 %) whilst private fanning would have been the major contributor wherever private milk production and consumption continued. The extent to which inhabitants consume natural foods from forests has a considerable effect on their 137 CS intake. The comparative importance of food products from natural ecosystems increases with time due to the long effective ecological half lives of 137 Cs in unimproved pastures and forests. Estimation of the contribution to the fluxes of 137 Cs from the different production and harvesting systems showed that the contribution from private farming and food harvesting from natural ecosystems may also be significant, contributing 14-30 % to the total fluxes of 137 Cs from an area even if the quantity of food produced in these systems is small. However, the major contributor to the flux exported from an area was the collective farming system, accounting for about 70-86 % of the total. Refs. 12 (author)

Kinetics of Cs adsorption on soils with different mineralogical composition

International Nuclear Information System (INIS)

Nakao, Atsushi; Funakawa, Shinya; Kosaki, Takashi

2004-01-01

137 Cs is one of the main radioisotopes released into the environment by nuclear powerstation accidents (e.g. Chernobyl) and nuclear weapons tests. Many studies have shown that Cs tends to remain at surface soils due to the high adsorption selectivity of clay minerals for this element. This behavior of the Cs + ion is, however, assumed to vary significantly depending on the mineralogical composition of the soil. The main objective of this study is to analyze the kinetics of Cs adsorption on soils with different mineralogical composition. Soil samples used in this study were Mollisols (Um) and Alfisols (Ua) from Ukraine, Ultisols (Tu) from Thailand and Spodosols (Js) from Japan. The dominant clay species of these soils are montmorillonite (Um, Ua), kaolinite and mica (Tu) and beidellite (Js). The rates of Cs adsorption and Ca or K desorption were measured using a continuous flow method. Soil samples that were previously saturated with Ca 2+ were leached with a 0.75 mmol/l Cs + solution at a constant rate of 2.0 ml/min. The leachate was collected every 10 minutes and the concentrations of Cs + , Ca 2+ and K + of each aliquot were measured by atomic adsorption spectrophotometry (Cs + , Ca 2+ ) and flame spectrophotometry (K + ). The datasets obtained were simulated using the first order kinetic model: y = a(1 - exp(-kt)), where a is the adsorption (desorption) maximum and k the rate constant. It is here assumed that Ca 2+ is desorbed from cation exchange sites and K + desorbed from the frayed edges of micaceous minerals. The values of a obtained for both Cs adsorption and Ca desorption was in the order Js>Um>Tu>Ua, whereas the values of k were in the order Tu>Ua>Um>Js. This result reflects the values of permanent negative charge of clays which are originated from the substitution of cations in the structure of 2:1 clay minerals. The value of a for K + desorption was, however, highest in Tu, suggesting that the values of Cs + -exchangeable K + correspond to the amount

Catalytic Mechanism of Nitrile Hydratase Proposed by Time-resolved X-ray Crystallography Using a Novel Substrate, tert-Butylisonitrile*S⃞

Science.gov (United States)

Hashimoto, Koichi; Suzuki, Hiroyuki; Taniguchi, Kayoko; Noguchi, Takumi; Yohda, Masafumi; Odaka, Masafumi

2008-01-01

Nitrile hydratases (NHases) have an unusual iron or cobalt catalytic center with two oxidized cysteine ligands, cysteine-sulfinic acid and cysteine-sulfenic acid, catalyzing the hydration of nitriles to amides. Recently, we found that the NHase of Rhodococcus erythropolis N771 exhibited an additional catalytic activity, converting tert-butylisonitrile (tBuNC) to tert-butylamine. Taking advantage of the slow reactivity of tBuNC and the photoreactivity of nitrosylated NHase, we present the first structural evidence for the catalytic mechanism of NHase with time-resolved x-ray crystallography. By monitoring the reaction with attenuated total reflectance-Fourier transform infrared spectroscopy, the product from the isonitrile carbon was identified as a CO molecule. Crystals of nitrosylated inactive NHase were soaked with tBuNC. The catalytic reaction was initiated by photo-induced denitrosylation and stopped by flash cooling. tBuNC was first trapped at the hydrophobic pocket above the iron center and then coordinated to the iron ion at 120 min. At 440 min, the electron density of tBuNC was significantly altered, and a new electron density was observed near the isonitrile carbon as well as the sulfenate oxygen of αCys114. These results demonstrate that the substrate was coordinated to the iron and then attacked by a solvent molecule activated by αCys114-SOH. PMID:18948265

Production of glycolipidic bio surfactants by environment bacteria: diversity and physiological part; Production de biosurfactants glycolipidiques par les bacteries de l`environnement: diversite et role physiologique

Energy Technology Data Exchange (ETDEWEB)

Arino, S

1996-10-09

About a hundred bacterial strains, isolated from soils, polluted or not by hydrocarbons, were tested for their capacity to excrete glycosides. The biggest productions were obtained for a soluble carbon source (glycerol) in a culture medium limited in the nitrogen source. In these conditions, 18 g/l of rhamnose lipids were produced by train Pseudomonas aeruginosa GL1 in a 200 h culture. Pseudomonas aeruginosa GL1, Cellulomonas celulans SA43 and Rhodococcus erythropolis DSM 43060 were studied in detail. The bio-surfactants produced were identified respectively as rhamnose lipids, oligosaccharide lipids and trehalose lipids, using various original analytical methods. Sugars and fatty acids composing these glycolipids had been shown to be usual components of the outer part of the cell wall in these microbial species. Moreover, cell hydrophobicity of the producing bacteria varied in time during culture. These results showed that both the cell wall and the extracellular glycolipids take part in the process of hydrocarbon uptake in the polluted environments. As other bacteria of the same species from different origins present the same characteristics, it may be concluded that glycolipid excretion does not constitute a specific response for hydrocarbon assimilation. In fact, a more general physiological role of glycolipids, concerning modifications of hydrophobic interfaces between the producing bacteria and their surrounding environment, could explain the production of glycolipids, and could also be utilized in hydrocarbon uptake. (author)

Ex situ bioremediation of oil-contaminated soil.

Science.gov (United States)

Lin, Ta-Chen; Pan, Po-Tsen; Cheng, Sheng-Shung

2010-04-15

An innovative bioprocess method, Systematic Environmental Molecular Bioremediation Technology (SEMBT) that combines bioaugmentation and biostimulation with a molecular monitoring microarray biochip, was developed as an integrated bioremediation technology to treat S- and T-series biopiles by using the landfarming operation and reseeding process to enhance the bioremediation efficiency. After 28 days of the bioremediation process, diesel oil (TPH(C10-C28)) and fuel oil (TPH(C10-C40)) were degraded up to approximately 70% and 63% respectively in the S-series biopiles. When the bioaugmentation and biostimulation were applied in the beginning of bioremediation, the microbial concentration increased from approximately 10(5) to 10(6) CFU/g dry soil along with the TPH biodegradation. Analysis of microbial diversity in the contaminated soils by microarray biochips revealed that Acinetobacter sp. and Pseudomonas aeruginosa were the predominant groups in indigenous consortia, while the augmented consortia were Gordonia alkanivorans and Rhodococcus erythropolis in both series of biopiles during bioremediation. Microbial respiration as influenced by the microbial activity reflected directly the active microbial population and indirectly the biodegradation of TPH. Field experimental results showed that the residual TPH concentration in the complex biopile was reduced to less than 500 mg TPH/kg dry soil. The above results demonstrated that the SEMBT technology is a feasible alternative to bioremediate the oil-contaminated soil. Crown Copyright 2009. Published by Elsevier B.V. All rights reserved.

Characterization of micro-organisms isolated from dairy industry after cleaning and fogging disinfection with alkyl amine and peracetic acid.

Science.gov (United States)

Bore, E; Langsrud, S

2005-01-01

To characterize micro-organisms isolated from Norwegian dairy production plants after cleaning and fogging disinfection with alkyl amine/peracetic acid and to indicate reasons for survival. Microbial samples were collected from five dairy plants after cleaning and fogging disinfection. Isolates from two of these production plants, which used fogging with alkylamino acetate (plant A), and peracetic acid (plant B), were chosen for further characterization. The sequence of the 16S ribosomal DNA, fatty acid analysis and biochemical characteristics were used to identify isolates. Three isolates identified as Rhodococcus erythropolis, Methylobacterium rhodesianum and Rhodotorula mucilaginosa were isolated from plant A and one Sphingomonas sp. and two M. extorquens from plant B. Different patterns of resistance to seven disinfectants in a bactericidal suspension test and variable degree of attachment to stainless steel were found. The strains with higher disinfectant resistance showed lower degree of attachment than susceptible strains. The study identifies and characterizes micro-organisms present after cleaning and fogging disinfection. Both surface attachment and resistance were shown as possible reasons for the presence of the isolates after cleaning and disinfection. These results contribute to the awareness of disinfectant resistance as well as attachment as mechanisms of survival in dairy industry. It also strengthens the argument of frequent alternation of disinfectants in the food processing industry to avoid the establishment of resistant house strains.

Characterization of ATPase activity of the AAA ARC from Bifidobacterium longum subsp. infantis.

Science.gov (United States)

Guzmán-Rodríguez, Mabel; de la Rosa, Ana Paulina Barba; Santos, Leticia

2015-01-01

Bifidobacteria are considered to be probiotics that exist in the large intestine and are helpful to maintain human health. Oral administration of bifidobacteria may be effective in improving the intestinal flora and environment, stimulating the immune response and possibly preventing cancer. However, for consistent and positive results, further well-controlled studies are urgently needed to describe the basic mechanisms of this microorganism. Analysis of the proteasome-lacking Bifidobacterium longum genome reveals that it possesses a gene, IPR003593 AAA ATPase core, which codes a 56 kDa protein containing one AAA ATPase domain. Phylogenetic classification made by CLANS, positioned this sequence into the ARC divergent branch of the AAA ATPase family of proteins. N-terminal analysis of the sequence indicates this protein is closely related to other ATPases such as the Rhodococcus erythropolis ARC, Archaeoglobus fulgidus PAN, Mycobacterium tuberculosis Mpa and the human proteasomal Rpt1 subunit. This gene was cloned, the full-length recombinant protein was overexpressed in Escherichia coli, purified as a high-molecular size complex and named Bl-ARC. Enzymatic characterization showed that Bl-ARC ATPase is active, Mg(+2)-dependent and sensitive to N-ethylmaleimide. Gene organization positions bl-arc in a region flanked by a cluster of genes that includes pup, dop and pafA genes. These findings point to a possible function as a chaperone in the degradation pathway via pupylation.

Transformation of Cs-IONSIV® into a ceramic wasteform by hot isostatic pressing

Science.gov (United States)

Chen, Tzu-Yu; Maddrell, Ewan R.; Hyatt, Neil C.; Gandy, Amy S.; Stennett, Martin C.; Hriljac, Joseph A.

2018-01-01

A simple method to directly convert Cs-exchanged IONSIV® IE-911 into a ceramic wasteform by hot isostatic pressing (1100 °C/190 MPa/2 hr) is presented. Two major Cs-containing phases, Cs2TiNb6O18 and Cs2ZrSi6O15, and a series of mixed oxides form. The microstructure and phase assemblage of the samples as a function of Cs content were examined using XRD, XRF, SEM and TEM/EDX. The chemical aqueous durability of the materials was investigated using the MCC-1 and PCT-B standard test methods. For HIPed Cs-IONSIV® samples, the MCC-1 normalised release rates of Cs were low rates are indicative of a safe long-term immobilisation matrix for Cs formed directly from spent IONSIV®. It was also demonstrated that the phase formation can be altered by adding Ti metal due to a controlled redox environment.

Effect of 137Cs on immunological reactivity

International Nuclear Information System (INIS)

Shubik, V.M.

1975-01-01

An important role of 137 Cs as a new ecological factor was shown by analyzing 31 different studies. The radioisotope may at present be detected in the organisms of all inhabitants of this planet. The migration of 137 Cs along the chain lichen-deer-man leads to its accumulation in the organism of humans living in the Extreme North and taking venison in their food. Although the high sensitivity of immunological reactions to various unfavourable environmental factors is well known, data on the effect of incorporated 137 Cs on immunity are scanty. Experiments on animals showed changes in factors of nonspecific immunity (phagocytic reaction of blood neutrophils, bactericidal activity, lysozyme and complement titres of blood serum) and specific immunity (formation of antiviral antibodies). The blood of animals injured by the isotope displays complete and incomplete autoantibodies. The dependence of immunobiological changes on the dose absorbed by the organism is shown. The 137 Cs intake of inhabitants of the Extreme North who eat venison did not, with the absorbed dose equalling up to 50 Mrem per year, lead to changes in their immunological reactivity. (author)

Effective half-lives of 137Cs in giant butterbur and field horsetail, and the distribution differences of potassium and 137Cs in aboveground tissue parts

International Nuclear Information System (INIS)

Tagami, Keiko; Uchida, Shigeo

2015-01-01

Concentrations of 137 Cs and 40 K in different tissues of edible wild herbaceous plants, that is, leaf blade and petiole for giant butterbur (Petasites japonicas (Siebold et Zucc.) Maxim.), and leaf, stem and strobilus for fertile shoot of field horsetail (Equisetum arvense L.) were measured in 2012–2014 to clarify the effect in Japan from the Fukushima Daiichi Nuclear Power Plant accident. The concentrations of 137 Cs decreased with time with effective half-lives of ca. 450 d and 360 d for giant butterbur and field horsetail, respectively. The ANOVA test revealed that 40 K and 137 Cs distributions in leaf blade and petiole for giant butterbur and leaf and stem for field horsetail were different. Therefore, other plants, leaf and stem for Japanese knotweed (Fallopia japonica (Houtt.) Ronse Decr.) and Canada goldenrod (Solidago canadensis L.), and leaf blade and petiole for gingko (Ginkgo biloba L.) and Someiyoshino cherry (Cerasus × yedoensis (Matsum.) A.V.Vassil. ‘Somei-yoshino’) were collected from the same sampling field and their 137 Cs and 40 K concentrations were compared to those in the giant butterbur and field horsetail parts. For 137 Cs, concentrations in leaf blade and leaf parts were 1.1–6.0 times higher than those in petiole and stem parts for all six plants. On the other hand, 40 K concentrations in leaf blade and leaf parts were 0.40–0.97 of those observed in petiole and stem parts. Discrimination ratios of 40 K/ 137 Cs of leaf blade to petiole or leaf to stem were then calculated and they ranged from 0.09 to 0.57. These results suggested that Cs and K did not behave similarly in these plants. Thus, to understand the radiocesium fate in plants, K measurement results should not be used as an analog for Cs behavior although Cs is known to have a similar chemical reactivity to that of K. - Highlights: • 137 Cs amounts in leaf blade and leaf were higher than those in petiole and stem in plants. • 40 K amounts in leaf blade and leaf

Plant remediation of soil contaminated with 137Cs

International Nuclear Information System (INIS)

Yang Juncheng; Zhang Jianfeng; Zhu Yongyi; Chen Jingjie; Mei Yong; Jiang Huimin

2005-01-01

A pot experiment was conducted to evaluate the bio-remediation of soils contaminated with 137 Cs. The selected plants are Cucurbita moschata Duchesne, Brassica chinensis L, Chloris virgata, Beta oulgaris L. Hongye, Beta oulgaris L. Dongshengye and Beta oulgaris L. The soils samples were taken from the paddy field, 2 km from the Dayawan nuclear power plant and Qinshan nuclear power plant, respectively, and cinnamon soil from the cultivated land in Beijing. The results show that all the employed species of plant have a higher accumulation to 137 Cs with the increased grade of the radioactivity of 137 Cs. A good correlation exist with the coefficient (r 2 ) of 0.9989. When the contaminated radioactivity of 137 Cs is in the same level the uptake of Cucurbita moschata Duchesne, Brassica chinensis L. and Chloris virgata increased with the decrease of pH value ranged 5.22-7.69. The ability of bioremediation in the orders were Chloris virgata, Brassica chinensis L., Beta oulgaris L. Hongye, Cucurbita moschata Duchesne, Beta oulgaris L. and Beta oulgaris L. Dongshengye, according to the comprehensive evaluation of transfer factor, specific activity of plant in dry weight of biomass and total absorption of 137 Cs by the individual plant in the same area. (authors)