31st IMAC Conference on Structural Dynamics

CERN Document Server

Adams, Douglas; Carrella, Alex; Mayes, Randy; Rixen, Daniel; Allen, Matt; Cunha, Alvaro; Catbas, Fikret; Pakzad, Shamim; Racic, Vitomir; Pavic, Aleksandar; Reynolds, Paul; Simmermacher, Todd; Cogan, Scott; Moaveni, Babak; Papadimitriou, Costas; Allemang, Randall; Clerck, James; Niezrecki, Christopher; Wicks, Alfred

2013-01-01

Topics in Nonlinear Dynamics, Volume 1: Proceedings of the 31st IMAC, A Conference and Exposition on Structural Dynamics, 2013, the first volume of seven from the Conference, brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Structural Dynamics, including papers on:   Nonlinear Oscillations Nonlinearities In Practice Nonlinear System Identification: Methods Nonlinear System Identification: Friction & Contact Nonlinear Modal Analysis Nonlinear Modeling & Simulation Nonlinear Vibration Absorbers Constructive Utilization of Nonlinearity.

32nd IMAC Conference and Exposition on Structural Dynamics

CERN Document Server

Mayes, Randy; Rixen, Daniel; Catbas, Fikret; Atamturktur, H; Moaveni, Babak; Papadimitriou, Costas; Schoenherr, Tyler; Foss, Gary; Niezrecki, Christopher; Allemang, Randall; Kerschen, Gaetan

2014-01-01

This critical collection examines a range of topics in modal analysis, from experimental techniques to acoustics to biodynamics,  as presented in early findings and case studies from the Proceedings of the 32nd IMAC, A Conference and Exposition on Structural Dynamics, 2014. The collection includes papers in the following general technical research areas: Experimental Techniques, Processing Modal Data, Rotating Machinery, Acoustics, Adaptive Structures, Biodynamics, Damping

First results from the BOXING (Birmingham-OCIW XMM and IMACS Nearby Groups) project.

Science.gov (United States)

Miles, T. A.; Raychaudhury, S.; Mulchaey, J. S.

2004-12-01

We present the first results from the BOXING (Birmingham-OCIW XMM and IMACS Nearby Groups) project, a collaboration between the Observatories of the Carnegie Institute of Washington (OCIW) and the University of Birmingham U.K. to study a sample of 25 galaxy groups (z ˜ 0.06) by means of optical photometry and spectroscopy (du Pont 2.5m; IMACS/Magellan) combined with x-ray observations (XMM). The combination of x-ray with optical data allows us to study the nature of the relationship between the properties of the groups and the galaxies that they contain. In this preliminary study, we present optical luminosity functions, which shows bimodal behavior in the poorer systems, interpreted as result of rapid merging. We also examine the dependence of galaxy morphology on local environment. Once spectroscopic observations are completed, we will be able to study velocity dispersions, star formation and nuclear activity in individual galaxies.

The IMACS Cluster Building Survey. I. Description of the Survey and Analysis Methods

Science.gov (United States)

Oemler Jr., Augustus; Dressler, Alan; Gladders, Michael G.; Rigby, Jane R.; Bai, Lei; Kelson, Daniel; Villanueva, Edward; Fritz, Jacopo; Rieke, George; Poggianti, Bianca M.;

THE IMACS CLUSTER BUILDING SURVEY. I. DESCRIPTION OF THE SURVEY AND ANALYSIS METHODS

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Oemler, Augustus Jr.; Dressler, Alan; Kelson, Daniel; Villanueva, Edward [Observatories of the Carnegie Institution for Science, 813 Santa Barbara St., Pasadena, CA 91101-1292 (United States); Gladders, Michael G. [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Rigby, Jane R. [Observational Cosmology Lab, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Bai Lei [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada); Fritz, Jacopo [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium); Rieke, George [Steward Observatory, University of Arizona, Tucson, AZ 8572 (United States); Poggianti, Bianca M.; Vulcani, Benedetta, E-mail: oemler@obs.carnegiescience.edu [INAF-Osservatorio Astronomico di Padova, Vicolo dell' Osservatorio 5, I-35122 Padova (Italy)

2013-06-10

The IMACS Cluster Building Survey uses the wide field spectroscopic capabilities of the IMACS spectrograph on the 6.5 m Baade Telescope to survey the large-scale environment surrounding rich intermediate-redshift clusters of galaxies. The goal is to understand the processes which may be transforming star-forming field galaxies into quiescent cluster members as groups and individual galaxies fall into the cluster from the surrounding supercluster. This first paper describes the survey: the data taking and reduction methods. We provide new calibrations of star formation rates (SFRs) derived from optical and infrared spectroscopy and photometry. We demonstrate that there is a tight relation between the observed SFR per unit B luminosity, and the ratio of the extinctions of the stellar continuum and the optical emission lines. With this, we can obtain accurate extinction-corrected colors of galaxies. Using these colors as well as other spectral measures, we determine new criteria for the existence of ongoing and recent starbursts in galaxies.

30th IMAC, A Conference on Structural Dynamics

CERN Document Server

Catbas, FN; Mayes, R; Rixen, D; Griffith, DT; Allemang, R; Clerck, J; Klerk, D; Simmermacher, T; Cogan, S; Chauhan, S; Cunha, A; Racic, V; Reynolds, P; Salyards, K; Adams, D; Kerschen, G; Carrella, A; Voormeeren, SN; Allen, MS; Horta, LG; Barthorpe, R; Niezrecki, C; Blough, JR; Vol.1 Topics on the Dynamics of Civil Structures; Vol.2 Topics in Experimental Dynamics Substructuring and Wind Turbine Dynamics; Vol.3 Topics in Nonlinear Dynamics; Vol.4 Topics in Model Validation and Uncertainty Quantification; Vol.5 Topics in Modal Analysis I; Vol.6 Topics in Modal Analysis II

2012-01-01

Topics on the Dynamics of Civil Structures, Volume 1, Proceedings of the 30th IMAC, A Conference and Exposition on Structural Dynamics, 2012, the first volume of six from the Conference, brings together 45 contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Structural Dynamics, including papers on: Human Induced Vibrations Bridge Dynamics Operational Modal Analysis Experimental Techniques and Modeling for Civil Structures System Identification for Civil Structures Method and Technologies for Bridge Monitoring Damage Detection for Civil Structures Structural Modeling Vibration Control Method and Approaches for Civil Structures Modal Testing of Civil Structures.

A MAGELLAN-IMACS-IFU SEARCH FOR DYNAMICAL DRIVERS OF NUCLEAR ACTIVITY. I. REDUCTION PIPELINE AND GALAXY CATALOG

International Nuclear Information System (INIS)

Westoby, P. B.; Mundell, C. G.; Maciejewski, W.; Baldry, I. K.; Nagar, N. M.; Emsellem, E.; Roth, M. M.; Gerssen, J.

2012-01-01

Using the IMACS integral-field unit (IFU) on the 6.5 m Magellan telescope, we have designed the first statistically significant investigation of the two-dimensional distribution and kinematics of ionized gas and stars in the central kiloparsec regions of a well-matched sample of Seyfert and inactive control galaxies selected from the Sloan Digital Sky Survey. The goals of the project are to use the fine spatial sampling (0.2 arcsec pixel –1 ) and large wavelength coverage (4000-7000 Å) of the IMACS-IFU to search for dynamical triggers of nuclear activity in the central region where active galactic nucleus (AGN) activity and dynamical timescales become comparable, to identify and assess the impact of AGN-driven outflows on the host galaxy and to provide a definitive sample of local galaxy kinematics for comparison with future three-dimensional kinematic studies of high-redshift systems. In this paper, we provide the first detailed description of the procedure to reduce and calibrate data from the IMACS-IFU in 'long mode' to obtain two-dimensional maps of the distribution and kinematics of ionized gas and stars. The sample selection criteria are presented, the observing strategy is described, and resulting maps of the sample galaxies are presented along with a description of the observed properties of each galaxy and the overall observed properties of the sample.

35th IMAC, A Conference and Exposition on Structural Dynamics 2017

CERN Document Server

Niezrecki, Christopher; Maio, Dario; Castellini, Paolo; Mains, Michael; Blough, JR; Kerschen, Gaetan; Caicedo, Juan; Pakzad, Shamim; Barthorpe, Robert; Platz, Roland; Lopez, Israel; Moaveni, Babak; Papadimitriou, Costas; v.1 Nonlinear dynamics; v.2 Dynamics of civil structures; v.3 Model validation and uncertainty quantification; v.4 Dynamics of coupled structures; v.5 Sensors and instrumentation; v.6 Special topics in structural dynamics; v.7 Structural health monitoring & damage detection; v.8 Rotating machinery, hybrid test methods, vibro-acoustics & laser vibrometry; v.9 Shock & vibration, aircraft/aerospace, energy harvesting, acoustics & optics; v.10 Topics in modal analysis & testing

2017-01-01

Nonlinear Dynamics, Volume 1: Proceedings of the 35th IMAC, A Conference and Exposition on Structural Dynamics, 2017, the first volume of ten from the Conference brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Nonlinear Dynamics, including papers on: Nonlinear System Identification Nonlinear Modeling & Simulation Nonlinear Reduced-order Modeling Nonlinearity in Practice Nonlinearity in Aerospace Systems Nonlinearity in Multi-Physics Systems Nonlinear Modes and Modal Interactions Experimental Nonlinear Dynamics.

Monotonous consumption of fibre-enriched bread at breakfast increases satiety and influences subsequent food intake.

Science.gov (United States)

Touyarou, Peio; Sulmont-Rossé, Claire; Gagnaire, Aude; Issanchou, Sylvie; Brondel, Laurent

2012-04-01

This study aimed to observe the influence of the monotonous consumption of two types of fibre-enriched bread at breakfast on hedonic liking for the bread, subsequent hunger and energy intake. Two groups of unrestrained normal weight participants were given either white sandwich bread (WS) or multigrain sandwich bread (MG) at breakfast (the sensory properties of the WS were more similar to the usual bread eaten by the participants than those of the MG). In each group, two 15-day cross-over conditions were set up. During the experimental condition the usual breakfast of each participant was replaced by an isocaloric portion of plain bread (WS or MG). During the control condition, participants consumed only 10 g of the corresponding bread and completed their breakfast with other foods they wanted. The results showed that bread appreciation did not change over exposure even in the experimental condition. Hunger was lower in the experimental condition than in the control condition. The consumption of WS decreased energy intake while the consumption of MG did not in the experimental condition compared to the corresponding control one. In conclusion, a monotonous breakfast composed solely of a fibre-enriched bread may decrease subsequent hunger and, when similar to a familiar bread, food intake. Copyright © 2011. Published by Elsevier Ltd.

Synthesis of Thermally Switchable Chromatographic Materials with Immobilized Ti4+ for Enrichment of Phosphopeptides by Reversible Addition Fragmentation Chain Transfer Polymerization

Science.gov (United States)

Wang, Di; Cao, Zhihan; Pang, Xinzhu; Deng, Yulin; Li, Bo; Dai, Rongji

2018-01-01

Reversible phosphorylation of proteins is one of the most crucial types of post-translational modifications (PTMs). And it shows significant work in diversified biological processes. However, the separation technology of phosphorylated peptides is still an analytical challenge in phosphoproteomics, because phosphopeptides are alway in low stoichiometry. Thus, enrichment of phosphopeptides before detection is indispensable. In this study, a novel temperature regulated separation protocol was developed. Silica@p (NIPAAm-co-IPPA)-Ti4+, a new Ti(IV)-IMAC (Immobilized Metal Affinity chromatography) materials was synthesized by reversible addition fragmentation chain transfer polymerization (RAFT). By the unique thermally responsive properties of poly(N-isopropylacrylamide) (PNIPAAm), the captured phosphorylated peptides could be released by changing temperature only without applying any other eluant which could damage the phosphopeptides. We employed isopropanol phosphonic acid (IPPA) as an IMAC ligand for the immobilization of Ti(IV) which could increase the specific adsorption of phosphopeptides. The enrichment and release properties were examined by treatment with pyridoxal 5’-phosphate (PLP) and casein phosphopeptides (CPP). Two phosphorylated compounds above have temperature-stimulated binding to Ti4+. Finally, silica@p (NIPAAm-co-IPPA)-Ti4+ was successfully employed in pretreatment of phosphopeptides in a tryptic digest of a-casein and human serum albumin (HSA). The results indicated a great potential of this new temperature-responsive material in phosphoproteomics study.

The Carnegie-Spitzer-IMACS redshift survey of galaxy evolution since z = 1.5. I. Description and methodology

Energy Technology Data Exchange (ETDEWEB)

Kelson, Daniel D.; Williams, Rik J.; Dressler, Alan; McCarthy, Patrick J.; Shectman, Stephen A.; Mulchaey, John S.; Villanueva, Edward V.; Crane, Jeffrey D.; Quadri, Ryan F. [The Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)

2014-03-10

We describe the Carnegie-Spitzer-IMACS (CSI) Survey, a wide-field, near-IR selected spectrophotometric redshift survey with the Inamori Magellan Areal Camera and Spectrograph (IMACS) on Magellan-Baade. By defining a flux-limited sample of galaxies in Spitzer Infrared Array Camera 3.6 μm imaging of SWIRE fields, the CSI Survey efficiently traces the stellar mass of average galaxies to z ∼ 1.5. This first paper provides an overview of the survey selection, observations, processing of the photometry and spectrophotometry. We also describe the processing of the data: new methods of fitting synthetic templates of spectral energy distributions are used to derive redshifts, stellar masses, emission line luminosities, and coarse information on recent star formation. Our unique methodology for analyzing low-dispersion spectra taken with multilayer prisms in IMACS, combined with panchromatic photometry from the ultraviolet to the IR, has yielded high-quality redshifts for 43,347 galaxies in our first 5.3 deg{sup 2} of the SWIRE XMM-LSS field. We use three different approaches to estimate our redshift errors and find robust agreement. Over the full range of 3.6 μm fluxes of our selection, we find typical redshift uncertainties of σ {sub z}/(1 + z) ≲ 0.015. In comparisons with previously published spectroscopic redshifts we find scatters of σ {sub z}/(1 + z) = 0.011 for galaxies at 0.7 ≤ z ≤ 0.9, and σ {sub z}/(1 + z) = 0.014 for galaxies at 0.9 ≤ z ≤ 1.2. For galaxies brighter and fainter than i = 23 mag, we find σ {sub z}/(1 + z) = 0.008 and σ {sub z}/(1 + z) = 0.022, respectively. Notably, our low-dispersion spectroscopy and analysis yields comparable redshift uncertainties and success rates for both red and blue galaxies, largely eliminating color-based systematics that can seriously bias observed dependencies of galaxy evolution on environment.

PSEUDOAFFINITY CHROMATOGRAPHY ENRICHMENT OF GLYCATED PEPTIDES FOR MONITORING ADVANCED GLYCATION END PRODUCTS (AGES IN METABOLIC DISORDERS

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Rajasekar R. Prasanna

2016-09-01

Full Text Available Advanced Glycation End (AGE products are produced due to diabetic progression and they are responsible for many complications in the diabetic disorder. The diabetic progression is measured, particularly following glycated hemoglobin using specific antibodies. However, the most abundant protein in blood, human serum albumin, is also found to be glycated which has a much shorter half life and gives information on short term glycemic control. In addition, glycated albumins are considered as markers of diabetic complications such as nephropathy, peripheral vascular calcification and also in Alzheimer’s disease. The glycation proceeds from the interaction between aldehyde group of sugar and the free amino group of the protein, resulting in the formation of Schiff’s base, which undergoes a series of modifications leading to generation of imidazoyl derivatives of amino acids known as Amadori rearrangement products. The imidazoyl derivatives from arginine and lysine are the most prominent modifications observed in proteins in the presence of reducing sugar and these imidazoyl derivatives have an affinity towards certain transition metal ions. Based on our earlier exhaustive work on trapping the histidine peptides using transition metal ion, Cu(II linked to imino-diacetate complex, we explored Cu(II immobilized metal affinity chromatography (IMAC as a potential tool for specific detection of glycated peptides of human serum albumin. Our results clearly demonstrate that Cu(II IMAC is able to detect glycated peptides very efficiently while the non-glycated forms were not retained on the Cu (II column as confirmed by LC-MS/MS analysis. We further discuss the utility of IMAC technology to enrich the detection of AGE products in plasma. We anticipate that these studies may provide valuable information on understanding disease pathologies and the potential of AGE products as biomarkers of various diseases including neurodegenerative, renal and

Enrichment and Identification of the Most Abundant Zinc Binding Proteins in Developing Barley Grains by Zinc-IMAC Capture and Nano LC-MS/MS

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Giuseppe Dionisio

2018-01-01

Full Text Available Background: Zinc accumulates in the embryo, aleurone, and subaleurone layers at different amounts in cereal grains. Our hypothesis is that zinc could be stored bound, not only to low MW metabolites/proteins, but also to high MW proteins as well. Methods: In order to identify the most abundant zinc binding proteins in different grain tissues, we microdissected barley grains into (1 seed coats; (2 aleurone/subaleurone; (3 embryo; and (4 endosperm. Initial screening for putative zinc binding proteins from the different tissue types was performed by fractionating proteins according to solubility (Osborne fractionation, and resolving those via Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE followed by polyvinylidene fluoride (PVDF membrane blotting and dithizone staining. Selected protein fractions were subjected to Zn2+-immobilized metal ion affinity chromatography, and the captured proteins were identified using nanoscale liquid chromatography coupled to tandem mass spectrometry (nanoLC-MS/MS. Results: In the endosperm, the most abundant zinc binding proteins were the storage protein B-hordeins, gamma-, and D-hordeins, while in the embryo, 7S globulins storage proteins exhibited zinc binding. In the aleurone/subaleurone, zinc affinity captured proteins were late abundant embryogenesis proteins, dehydrins, many isoforms of non-specific lipid transfer proteins, and alpha amylase trypsin inhibitor. Conclusions: We have shown evidence that abundant barley grain proteins have been captured by Zn-IMAC, and their zinc binding properties in relationship to the possibility of zinc storage is discussed.

Assessment of phosphopeptide enrichment/precipitation method for LC-MS/MS based phosphoproteomic analysis of plant tissue

DEFF Research Database (Denmark)

Ye, Juanying; Rudashevskaya, Elena; Hansen, Thomas Aarup

thaliana (Col-0) leaves using a two-phase partitioning system. The concentration of plasma membrane protein was determined by Bradford assay. Protein was digested with Lys-C for 4 hours and then by trypsin overnight. The peptide mixture was purified with IMAC, TiO2, CPP, SIMAC (IMAC+TiO2), the combination...

Highly selective enrichment of phosphorylated peptides from peptide mixtures using titanium dioxide microcolumns

DEFF Research Database (Denmark)

Larsen, Martin Røssel; Thingholm, Tine E; Jensen, Ole N

2005-01-01

based on TiO2microcolumns and peptide loading in 2,5-dihydroxybenzoic acid (DHB). The effect of DHB was a very efficient reduction in the binding of nonphosphorylated peptides to TiO2 while retaining its high binding affinity for phosphorylated peptides. Thus, inclusion of DHB dramatically increased...... the selectivity of the enrichment of phosphorylated peptides by TiO2. We demonstrated that this new procedure was more selective for binding phosphorylated peptides than IMAC using MALDI mass spectrometry. In addition, we showed that LC-ESI-MSMS was biased toward monophosphorylated peptides, whereas MALDI MS...... was not. Other substituted aromatic carboxylic acids were also capable of specifically reducing binding of nonphosphorylated peptides, whereas phosphoric acid reduced binding of both phosphorylated and nonphosphorylated peptides. A putative mechanism for this intriguing effect is presented....

Enrichment and separation of mono- and multiply phosphorylated peptides using sequential elution from IMAC prior to mass spectrometric analysis

DEFF Research Database (Denmark)

Thingholm, Tine E; Jensen, Ole N; Larsen, Martin R

2009-01-01

Phospho-proteomics relies on methods for efficient purification and sequencing of phosphopeptides from highly complex biological systems using low amounts of starting material. Current methods for phosphopeptide enrichment, e.g., immobilized metal affinity chromatography and titanium dioxide chro...

Coordination of two high-affinity hexamer peptides to copper(II) and palladium(II) models of the peptide-metal chelation site on IMAC resins.

Science.gov (United States)

Chen, Y; Pasquinelli, R; Ataai, M; Koepsel, R R; Kortes, R A; Shepherd, R E

2000-03-20

The coordination of peptides Ser-Pro-His-His-Gly-Gly (SPHHGG) and (His)6 (HHHHHH) to [PdII(mida)(D2O)] (mida2- = N-methyliminodiacetate) was studied by 1H NMR as model reactions for CuII(iminodiacetate)-immobilized metal affinity chromatography (IMAC) sites. This is the first direct physical description of peptide coordination for IMAC. A three-site coordination is observed which involves the first, third, and fourth residues along the peptide chain. The presence of proline in position 2 of SPHHGG achieves the best molecular mechanics and bonding angles in the coordinated peptide and enhances the interaction of the serine amino nitrogen. Histidine coordination of H1, H3, and H4 of (His)6 and H3 and H4 of SPHHGG was detected by 1H NMR contact shifts and H/D exchange of histidyl protons. The EPR spectra of SPHHGG and HHHHHH attached to the [CuII(mida)] unit were obtained for additional modeling of IMAC sites. EPR parameters of the parent [Cu(mida)(H2O)2] complex are representative: gzz = 2.31; gyy = 2.086; gxx = 2.053; A parallel = 161G; AN = 19G (three line, one N coupling). Increased rhombic distortion is detected relative to the starting aqua complex in the order of [Cu(mida)L] for distortion of HHHHHH > SPHHGG > (H2O)2. The lowering of symmetry is also seen in the decrease in the N-shf coupling, presumably to the imino nitrogen of mida2- in the order 19 G (H2O), 16 G (SPHHGG) and 11 G (HHHHHH). Visible spectra of the [Cu(mida)(SPHHGG)] and [Cu(mida)(HHHHHH)] as a function of pH indicate coordination of one histidyl donor at ca. 4.5, two in the range of pH 5-7, and two chelate ring attachments involving the terminal amino donor for SPHHGG or another histidyl donor of HHHHHH in the pH domain of 7-8 in agreement with the [PdII(mida)L] derivatives which form the two-chelate-ring attachment even at lower pH as shown by the 1H NMR methods.

Nonlinear model updating applied to the IMAC XXXII Round Robin benchmark system

Science.gov (United States)

Kurt, Mehmet; Moore, Keegan J.; Eriten, Melih; McFarland, D. Michael; Bergman, Lawrence A.; Vakakis, Alexander F.

2017-05-01

We consider the application of a new nonlinear model updating strategy to a computational benchmark system. The approach relies on analyzing system response time series in the frequency-energy domain by constructing both Hamiltonian and forced and damped frequency-energy plots (FEPs). The system parameters are then characterized and updated by matching the backbone branches of the FEPs with the frequency-energy wavelet transforms of experimental and/or computational time series. The main advantage of this method is that no nonlinearity model is assumed a priori, and the system model is updated solely based on simulation and/or experimental measured time series. By matching the frequency-energy plots of the benchmark system and its reduced-order model, we show that we are able to retrieve the global strongly nonlinear dynamics in the frequency and energy ranges of interest, identify bifurcations, characterize local nonlinearities, and accurately reconstruct time series. We apply the proposed methodology to a benchmark problem, which was posed to the system identification community prior to the IMAC XXXII (2014) and XXXIII (2015) Conferences as a "Round Robin Exercise on Nonlinear System Identification". We show that we are able to identify the parameters of the non-linear element in the problem with a priori knowledge about its position.

A novel strategy for phosphopeptide enrichment using lanthanide phosphate co-precipitation.

Science.gov (United States)

Mirza, Munazza Raza; Rainer, Matthias; Güzel, Yüksel; Choudhary, Iqbal M; Bonn, Günther K

2012-08-01

Reversible phosphorylation of proteins is a common theme in the regulation of important cellular functions such as growth, metabolism, and differentiation. The comprehensive understanding of biological processes requires the characterization of protein phosphorylation at the molecular level. Although, the number of cellular phosphoproteins is relatively high, the phosphorylated residues themselves are generally of low abundance due to the sub-stoichiometric nature. However, low abundance of phosphopeptides and low degree of phosphorylation typically necessitates isolation and concentration of phosphopeptides prior to mass spectrometric analysis. In this study, we used trivalent lanthanide ions (LaCl(3), CeCl(3), EuCl(3), TbCl(3), HoCl(3), ErCl(3), and TmCl(3)) for phosphopeptide enrichment and cleaning-up. Due to their low solubility product, lanthanide ions form stable complexes with the phosphate groups of phosphopeptides and precipitate out of solution. In a further step, non-phosphorylated compounds can easily be removed by simple centrifugation and washing before mass spectrometric analysis using Matrix-assisted laser desorption/ionisation-time of flight. The precipitation method was applied for the isolation of phosphopeptides from standard proteins such as ovalbumin, α-casein, and β-casein. High enrichment of phosphopeptides could also be achieved for real samples such as fresh milk and egg white. The technology presented here represents an excellent and highly selective tool for phosphopeptide recovery; it is easily applicable and shows several advantages as compared with standard approaches such as TiO(2) or IMAC.

Optimized expression in Pichia pastoris eliminates common protein contaminants from subsequent His-tag purification.

Science.gov (United States)

Chen, Yong; Li, Yang; Liu, Peng; Sun, Qun; Liu, Zhu

2014-04-01

A weakness of using immobilized metal affinity chromatography (IMAC) to purify recombinant proteins expressed in Pichia pastoris is the co-purification of native proteins that exhibit high affinities for Ni-IMAC. We have determined the elution profiles of P. pastoris proteins and have examined the native proteins that co-purify when eluting with 100 mM imidazole. Four major contaminants were identified: mitochondrial alcohol dehydrogenase isozyme III (mADH), nucleotide excision repair endonuclease, and the hypothetical proteins TPHA_0L01390 and TDEL_0B02190 which are homologous proteins derived from Tetrapisispora phaffii and Torulaspora delbrueckii, respectively. A new P. pastoris expression strain was engineered that eliminated the predominant contaminant, mADH, by gene disruption. The total amount of protein contaminants was reduced by 55 % without effecting cell growth. The present study demonstrates the feasibility of using a proteomic approach to facilitate bioprocess optimization.

Limitations in SELDI-TOF MS whole serum proteomic profiling with IMAC surface to specifically detect colorectal cancer

International Nuclear Information System (INIS)

Wang, Qi; Gu, Jin; Shen, Jing; Li, Zhen-fu; Jie, Jian-zheng; Wang, Wen-yue; Wang, Jin; Zhang, Zhong-tao; Li, Zhi-xia; Yan, Li

2009-01-01

Surface enhanced laser desorption and ionization time-of-flight mass spectrometry (SELDI-TOF-MS) analysis on serum samples was reported to be able to detect colorectal cancer (CRC) from normal or control patients. We carried out a validation study of a SELDI-TOF MS approach with IMAC surface sample processing to identify CRC. A retrospective cohort of 338 serum samples including 154 CRCs, 67 control cancers and 117 non-cancerous conditions was profiled using SELDI-TOF-MS. No CRC 'specific' classifier was found. However, a classifier consisting of two protein peaks separates cancer from non-cancerous conditions with high accuracy. In this study, the SELDI-TOF-MS-based protein expression profiling approach did not perform to identify CRC. However, this technique is promising in distinguishing patients with cancer from a non-cancerous population; it may be useful for monitoring recurrence of CRC after treatment

Sequential elution from IMAC (SIMAC)

DEFF Research Database (Denmark)

Thingholm, Tine E.; Larsen, Martin R.

2016-01-01

Phosphoproteomics relies on methods for efficient purification and sequencing of phosphopeptides from highly complex biological systems, especially when using low amounts of starting material. Current methods for phosphopeptide enrichment, e.g., Immobilized Metal ion Affinity Chromatography and t...

Stable isotope enrichment: Current and future potential

International Nuclear Information System (INIS)

Tracy, J.G.; Aaron, W.S.

1992-01-01

Oak Ridge National Laboratory (ORNL) operates the Isotope Enrichment Facility for the purpose of providing enriched stable isotopes, selected radioactive isotopes (including the actinides), and isotope-related materials and services for use in various research applications. ORNL is responsible for isotope enrichment and the distribution of approximately 225 nongaseous stable isotopes from 50 multi-isotopic elements. Many enriched isotope products are of prime importance in the fabrication of nuclear targets and the subsequent production of special radionuclides. State-of-the-art techniques to achieve special isotopic, chemical, and physical requirements are performed at ORNL This report describes the status and capabilities of the Isotope Enrichment Facility and the Isotope Research Materials Laboratory as well as emphasizing potential advancements in enrichment capabilities

Stable isotope enrichment - current and future potential

International Nuclear Information System (INIS)

Tracy, J.G.; Aaron, W.S.

1993-01-01

Oak Ridge National Laboratory (ORNL) operates the Isotope Enrichment Facility for the purpose of providing enriched stable isotopes, selected radioactive isotopes (including the actinides), and isotope-related materials and services for use in various research applications. ORNL is responsible for isotope enrichment and the distribution of approximately 225 nongaseous stable isotopes from 50 multi-isotopic elements. Many enriched isotope products are of prime importance in the fabrication of nuclear targets and the subsequent production of special radionuclides. State-of-the-art techniques to achieve special isotopic, chemical, and physical requirements are performed at ORNL. This report describes the status and capabilities of the Isotope Enrichment Facility and the Isotope Research Materials Laboratory as well as emphasizing potential advancements in enrichment capabilities. (orig.)

The Effect of Cyanobacterial Biomass Enrichment by Centrifugation and GF/C Filtration on Subsequent Microcystin Measurement

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Shelley Rogers

2015-03-01

Full Text Available Microcystins are cyclic peptides produced by multiple cyanobacterial genera. After accumulation in the liver of animals they inhibit eukaryotic serine/threonine protein phosphatases, causing liver disease or death. Accurate detection/quantification of microcystins is essential to ensure safe water resources and to enable research on this toxin. Previous methodological comparisons have focused on detection and extraction techniques, but have not investigated the commonly used biomass enrichment steps. These enrichment steps could modulate toxin production as recent studies have demonstrated that high cyanobacterial cell densities cause increased microcystin levels. In this study, three microcystin-producing strains were processed using no cell enrichment steps (by direct freezing at three temperatures and with biomass enrichment (by centrifugation or GF/C filtration. After extraction, microcystins were analyzed using liquid chromatography-tandem mass spectrometry. All processing methods tested, except GF/C filtration, resulted in comparable microcystin quotas for all strains. The low yields observed for the filtration samples were caused by adsorption of arginine-containing microcystins to the GF/C filters. Whilst biomass enrichment did not affect microcystin metabolism over the time-frame of normal sample processing, problems associated with GF/C filtration were identified. The most widely applicable processing method was direct freezing of samples as it could be utilized in both field and laboratory environments.

78 FR 72072 - Proposed Subsequent Arrangement

Science.gov (United States)

2013-12-02

... g of U.S.-origin atomized low-enriched uranium-7wt. % molybdenum powder, containing 365.638 g in the..., which is located at and was prepared by KAERI, will be used for the irradiation test of full-size fuel... subsequent arrangement concerning the retransfer of nuclear material of United States origin will not be...

TRIGA low enrichment fuel

International Nuclear Information System (INIS)

Gietzen, A.

1993-01-01

Sixty TRIGA reactors have been sold and the earliest of these are now passing twenty years of operation. All of these reactors use the uranium zirconium hydride fuel (UZrH) which provides certain unique advantages arising out of its large prompt negative temperature coefficient, very low fission product release, and high temperature capability. Eleven of these Sixty reactors are conversions from plate fuel to TRIGA fuel which were made as a result of these advantages. With only a few exceptions, TRIGA reactors have always used low-enriched uranium (LEU) fuel with an enrichment of 19.9%. The exceptions have either been converted from the standard low-enriched fuel to the 70% enriched FLIP fuel in order to achieve extended lifetime, or are higher powered reactors which were designed for long life using 93%-enriched uranium during the time when the use and export of highly enriched uranium (HEU) was not restricted. The advent of international policies focusing attention on nonproliferation and safeguards made the HEU fuels obsolete. General Atomic immediately undertook a development effort (nearly two years ago) in order to be in a position to comply with these policies for all future export sales and also to provide a low-enriched alternative to fully enriched plate-type fuels. This important work was subsequently partially supported by the U.S. Department of Energy. The laboratory and production tests have shown that higher uranium densities can be achieved to compensate for reducing the enrichment to 20%, and that the fuels maintain the characteristics of the very thoroughly proven standard TRIGA fuels. In May of 1978, General Atomic announced that these fuels were available for TRIGA reactors and for plate-type reactors with power levels up to 15 MW with General Atomic's standard commercial warranty

TRIGA low enrichment fuel

International Nuclear Information System (INIS)

Gietzen, A.

1993-01-01

Sixty TRIGA reactors have been sold and the earliest of these are now passing twenty years of operation. All of these reactors use the uranium-zirconium hydride fuel (UZrH) which provides certain unique advantages arising out of its large prompt negative temperature coefficient, very low fission product release, and high temperature capability. Eleven of these Sixty reactors are conversions from plate fuel to TRIGA fuel which were made as a result of these advantages. With only a few exceptions, TRIGA reactors have always used low-enriched-uranium (LEU) fuel with an enrichment of 19.9%. The exceptions have either been converted from the standard low-enriched fuel to the 70% enriched FLIP fuel in order to achieve extended lifetime, or are higher powered reactors which were designed for long life using 93%-enriched uranium during the time when the use and export of highly enriched uranium (HEU) was not restricted. The advent of international policies focusing attention on nonproliferation and safeguards made the HEU fuels obsolete. General Atomic immediately undertook a development effort (nearly two years ago) in order to be in a position to comply with these policies for all future export sales and also to provide a low-enriched alternative to fully enriched plate-type fuels. This important work was subsequently partially supported by the U.S. Department of Energy. The laboratory and production tests have shown that higher uranium densities can be achieved to compensate for reducing the enrichment to 20%, and that the fuels maintain the characteristics of the very thoroughly proven standard TRIGA fuels. In May of 1978, General Atomic announced that these fuels were available for TRIGA reactors and for plate-type reactors with power levels up to 15 MW with GA's standard commercial warranty

Inoculation stress hypothesis of environmental enrichment.

Science.gov (United States)

Crofton, Elizabeth J; Zhang, Yafang; Green, Thomas A

2015-02-01

One hallmark of psychiatric conditions is the vast continuum of individual differences in susceptibility vs. resilience resulting from the interaction of genetic and environmental factors. The environmental enrichment paradigm is an animal model that is useful for studying a range of psychiatric conditions, including protective phenotypes in addiction and depression models. The major question is how environmental enrichment, a non-drug and non-surgical manipulation, can produce such robust individual differences in such a wide range of behaviors. This paper draws from a variety of published sources to outline a coherent hypothesis of inoculation stress as a factor producing the protective enrichment phenotypes. The basic tenet suggests that chronic mild stress from living in a complex environment and interacting non-aggressively with conspecifics can inoculate enriched rats against subsequent stressors and/or drugs of abuse. This paper reviews the enrichment phenotypes, mulls the fundamental nature of environmental enrichment vs. isolation, discusses the most appropriate control for environmental enrichment, and challenges the idea that cortisol/corticosterone equals stress. The intent of the inoculation stress hypothesis of environmental enrichment is to provide a scaffold with which to build testable hypotheses for the elucidation of the molecular mechanisms underlying these protective phenotypes and thus provide new therapeutic targets to treat psychiatric/neurological conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Development of long-life low enrichment fuel

International Nuclear Information System (INIS)

Gietzen, A.J.; West, G.B.

1978-01-01

With only a few exceptions, TRIGA reactors have always used low-enriched-uranium (LEU) fuel with an enrichment of 19.9%. The exceptions have either been converted from the standard low-enriched fuel to the 70% enriched FLIP fuel in order to achieve extended lifetime, or are higher powered reactors which were designed for long life using 93%-enriched uranium during the time when the use and export of highly enriched uranium (HEU) was not restricted. The advent of international policies focusing attention on non-proliferation and safeguards made the HEU fuels obsolete. General Atomic immediately undertook a development effort (nearly two years ago) in order to be in a position to comply with these policies for all future export sales and also to provide a low-enriched alternative to fully enriched plate-type fuels. This important work was subsequently partially supported by the U. S. Department of Energy. The laboratory and production tests have shown that higher uranium densities can be achieved to compensate for reducing the enrichment to 20%, and that the fuels maintain the characteristics of the very thoroughly proven standard TRIGA fuels. In May of this year, General Atomic announced that these fuels were available for TRIGA reactors and for plate-type reactors with power levels up to 15 MW with GA's standard commercial warranty

Salmonella testing of pooled pre-enrichment broth cultures for screening multiple food samples.

Science.gov (United States)

Price, W R; Olsen, R A; Hunter, J E

1972-04-01

A method has been described for testing multiple food samples for Salmonella without loss in sensitivity. The method pools multiple pre-enrichment broth cultures into single enrichment broths. The subsequent stages of the Salmonella analysis are not altered. The method was found applicable to several dry food materials including nonfat dry milk, dried egg albumin, cocoa, cottonseed flour, wheat flour, and shredded coconut. As many as 25 pre-enrichment broth cultures were pooled without apparent loss in the sensitivity of Salmonella detection as compared to individual sample analysis. The procedure offers a simple, yet effective, way to increase sample capacity in the Salmonella testing of foods, particularly where a large proportion of samples ordinarily is negative. It also permits small portions of pre-enrichment broth cultures to be retained for subsequent individual analysis if positive tests are found. Salmonella testing of pooled pre-enrichment broths provides increased consumer protection for a given amount of analytical effort as compared to individual sample analysis.

Environmental enrichment imparts disease-modifying and transgenerational effects on genetically-determined epilepsy and anxiety.

Science.gov (United States)

Dezsi, Gabi; Ozturk, Ezgi; Salzberg, Michael R; Morris, Margaret; O'Brien, Terence J; Jones, Nigel C

2016-09-01

The absence epilepsies are presumed to be caused by genetic factors, but the influence of environmental exposures on epilepsy development and severity, and whether this influence is transmitted to subsequent generations, is not well known. We assessed the effects of environmental enrichment on epilepsy and anxiety outcomes in multiple generations of GAERS - a genetic rat model of absence epilepsy that manifests comorbid elevated anxiety-like behaviour. GAERS were exposed to environmental enrichment or standard housing beginning either prior to, or after epilepsy onset, and underwent EEG recordings and anxiety testing. Then, we exposed male GAERS to early enrichment or standard housing and generated F1 progeny, which also underwent EEG recordings. Hippocampal CRH mRNA expression and DNA methylation were assessed using RT-PCR and pyrosequencing, respectively. Early environmental enrichment delayed the onset of epilepsy in GAERS, and resulted in fewer seizures in adulthood, compared with standard housed GAERS. Enrichment also reduced the frequency of seizures when initiated in adulthood. Anxiety levels were reduced by enrichment, and these anti-epileptogenic and anxiolytic effects were heritable into the next generation. We also found reduced expression of CRH mRNA in GAERS exposed to enrichment, but this was not due to changes in DNA methylation. Environmental enrichment produces disease-modifying effects on genetically determined absence epilepsy and anxiety, and these beneficial effects are transferable to the subsequent generation. Reduced CRH expression was associated with these phenotypic improvements. Environmental stimulation holds promise as a naturalistic therapy for genetically determined epilepsy which may benefit subsequent generations. Copyright © 2016 Elsevier Inc. All rights reserved.

The enriched chromium neutrino source for GALLEX

International Nuclear Information System (INIS)

Hartmann, F.X.; Hahn, R.L.

1991-01-01

The preparation and study of an intense source of neutrinos in the form of neutron irradiated materials which are enriched in Cr-50 for use in the GALLEX solar neutrino experiment are discussed. Chromyl fluoride gas is enriched in the Cr-50 isotope by gas centrifugation and subsequently converted to a very stable form of chromium oxide. The results of neutron activation analyses of such chromium samples indicate low levels of any long-lived activities, but show that short-lived activities, in particular Na-24, may be of concern. These results show that irradiating chromium oxide enriched in Cr-50 is preferable to irradiating either natural chromium or argon gas as a means of producing a neutrino source to calibrate the GALLEX detector. These results of the impurity level analysis of the enriched chromyl fluoride gas and its conversion to the oxide are also of interest to work in progress by other members of the Collaboration investigating an alternative conversion of the enriched gas to chromium metal. 35 refs., 12 figs., 5 tabs

Remote Handling Devices for Disposition of Enriched Uranium Reactor Fuel Using Melt-Dilute Process

International Nuclear Information System (INIS)

Heckendorn, F.M.

2001-01-01

Remote handling equipment is required to achieve the processing of highly radioactive, post reactor, fuel for the melt-dilute process, which will convert high enrichment uranium fuel elements into lower enrichment forms for subsequent disposal. The melt-dilute process combines highly radioactive enriched uranium fuel elements with deleted uranium and aluminum for inductive melting and inductive stirring steps that produce a stable aluminum/uranium ingot of low enrichment

Iminodiacetic acid-modified magnetic poly(2-hydroxyethyl methacrylate)-based microspheres for phosphopeptide enrichment

Czech Academy of Sciences Publication Activity Database

Novotná, L.; Emmerová, T.; Horák, Daniel; Kučerová, Z.; Tichá, M.

2010-01-01

Roč. 1217, č. 51 (2010), s. 8032-8040 ISSN 0021-9673 R&D Projects: GA AV ČR(CZ) KAN401220801; GA ČR GA203/09/0857; GA ČR GAP503/10/0664 Institutional research plan: CEZ:AV0Z40500505 Keywords : IMAC phosphopeptide separation * IDA-modified magnetic microspheres * Porcine pepsin A Subject RIV: EE - Microbiology, Virology Impact factor: 4.194, year: 2010

THE IMACS CLUSTER BUILDING SURVEY. III. THE STAR FORMATION HISTORIES OF FIELD GALAXIES

Energy Technology Data Exchange (ETDEWEB)

Oemler, Augustus Jr.; Dressler, Alan [Observatories of the Carnegie Institution for Science, 813 Santa Barbara St., Pasadena, CA 91101-1292 (United States); Gladders, Michael G.; Abramson, Louis [Department of Astronomy and Astrophysics, University of Chicago, Chicago, IL 60637 (United States); Fritz, Jacopo [Sterrenkundig Observatorium, Universiteit Gent, Krijgslaan 281 S9, B-9000 Gent (Belgium); Poggianti, Bianca M.; Vulcani, Benedetta [INAF-Osservatorio Astronomico di Padova, vicolo dell' Osservatorio 5, I-35122 Padova (Italy)

2013-06-10

Using data from the IMACS Cluster Building Survey and from nearby galaxy surveys, we examine the evolution of the rate of star formation in field galaxies from z = 0.60 to the present. Fitting the luminosity function to a standard Schechter form, we find a rapid evolution of M{sub B}{sup *} consistent with that found in other deep surveys; at the present epoch M{sub B}{sup *} is evolving at the rate of 0.38 Gyr{sup -1}, several times faster than the predictions of simple models for the evolution of old, coeval galaxies. The evolution of the distribution of specific star formation rates (SSFRs) is also too rapid to explain by such models. We demonstrate that starbursts cannot, even in principle, explain the evolution of the SSFR distribution. However, the rapid evolution of both M{sub B}{sup *} and the SSFR distribution can be explained if some fraction of galaxies have star formation rates characterized by both short rise and fall times and by an epoch of peak star formation more recent than the majority of galaxies. Although galaxies of every stellar mass up to 1.4 Multiplication-Sign 10{sup 11} M{sub Sun} show a range of epochs of peak star formation, the fraction of ''younger'' galaxies falls from about 40% at a mass of 4 Multiplication-Sign 10{sup 10} M{sub Sun} to zero at a mass of 1.4 Multiplication-Sign 10{sup 11} M{sub Sun }. The incidence of younger galaxies appears to be insensitive to the density of the local environment; but does depend on group membership: relatively isolated galaxies are much more likely to be young than are group members.

The Helikon technique for isotope enrichment

International Nuclear Information System (INIS)

Haarhoff, P.C.

1976-11-01

The separating element employed in the UCOR process for uranium enrichment has an enriched stream which is much smaller than the depleted stream. To deal with this small cut and to exploit the full potential of the process, a new cascade technique has been developed, the so-called helikon technique. It is based on the principle that an axial flow compressor can simultaneously compress a number of streams of different isotopic composition, which flow through it in parallel, without any significant mixing between them. The technique makes it possible to achieve the desired enrichment with a relatively small number of separating units, by making the best use of the high enrichment factor available. A further feature of the helikon technique is that a module yields an enrichment factor which is not constant, but can vary. In this way a cascade can be built up from modules of a fixed size, which is a great advantage when compared to conventional cascade arrangements where several unit sizes are required. A general theoretical treatment of the helikon technique is given and the similarity between helikon and conventional cascades is pointed out. Practical helikon cascades are subsequently discussed on the basis of the UCOR process

Linking nutrient enrichment, sediment erodibility and biofilms

Science.gov (United States)

Conrad, B.; Mahon, R.; Sojka, S. L.

2014-12-01

Sediment movement in coastal lagoons affects nutrient flux and primary producer growth. Previous research has shown that sediment erodibility is affected by biofilm concentration and that growth of benthic organisms, which produce biofilm, is affected by nutrient enrichment. However, researchers have not examined possible links between nutrient addition and sediment erodibility. We manipulated nutrient levels in the water column of 16 microcosms filled with homogenized sediment from a shallow coastal lagoon and artificial seawater to determine the effects on biofilm growth, measured through chlorophyll a and colloidal carbohydrate concentrations. Erosion tests using a Gust microcosm were conducted to determine the relationship between sediment erodibility and biofilm concentration. Results show that carbohydrate levels decreased with increasing nutrient enrichment and were unrelated to chlorophyll concentrations and erodibility. The nutrient levels did not predictably affect the chlorophyll levels, with lower chlorophyll concentrations in the control and medium enrichment treatments than the low and high enrichment treatments. Controls on biofilm growth are still unclear and the assumed relationship between carbohydrates and erodibility may be invalid. Understanding how biofilms respond to nutrient enrichment and subsequent effects on sediment erodibility is essential for protecting and restoring shallow coastal systems.

Acute effects of protein composition and fibre enrichment of yogurt consumed as snacks on appetite sensations and subsequent ad libitum energy intake in healthy men.

Science.gov (United States)

Doyon, Caroline Y; Tremblay, Angelo; Rioux, Laurie-Eve; Rhéaume, Caroline; Cianflone, Katherine; Poursharifi, Pegah; Turgeon, Sylvie L

2015-10-01

The objective of the study was to assess the impact of protein composition and/or fibre enrichment of yogurt on appetite sensations and subsequent energy intake. In this double-blind crossover study, 20 healthy men (aged 32.4 ± 9.1 years) were submitted to 5 randomized testing sessions, during which they had to consume 5 isocaloric and isonproteinemic yogurt snacks (120-g servings, ∼230 kJ, ∼4.5 g protein) differing by their casein-to-whey protein ratio (C:W) or dietary fibre content: (i) control C:W = 2.8:1; (ii) high whey (HW) C:W = 1.5:1, and fibre-enriched formulations using control; (iii) 2.4 g of inulin; (iv) 1.9 g of inulin and 0.5 g of β-glucan (+IN-βG); and (v) 0.5 g of β-glucan. Appetite sensations were assessed using 150-mm visual analog scales. Plasma variables (glucose, insulin, ghrelin) were measured at 30-min intervals post-yogurt consumption for 2 h. Finally, energy intakes during ad libitum lunches offered 2 h after yogurt snacks were recorded. None of the yogurts impacted appetite sensations. Ad libitum energy intake was significantly different only between HW and control yogurts (-812 kJ; p = 0.03). Regarding post-yogurt plasma variables, a significant difference was found only between ghrelin area under the curve of the +IN-βG and the HW yogurts (-15 510 pmol/L per 120 min, p = 0.04). In conclusion, although appetite sensations were not influenced by variations in yogurts' protein compositions, a reduced energy intake was observed during the ad libitum lunch after the HW yogurt that may be attributable to its lower C:W. Surprisingly, the fibre enrichments studied did not exert effect on appetite sensations and energy intake.

Measurement of 235U enrichment with a LaBr3 scintillation detector

International Nuclear Information System (INIS)

Mortreau, P.; Berndt, R.

2010-01-01

This paper describes the performance of a 1.5 in.x1.5 in. LaBr 3 gamma radiation detector for determining 235 U enrichment by non-destructive analysis. The spectrometric properties of the detector, brought to market under the trade name BrillanCe-380 , were first evaluated. Enrichment measurements were subsequently carried out in different experimental conditions on certified uranium samples with enrichment ranging from 0.31% to 60% and on UF 6 containers of the type 30B and 48Y.

Enriched lithium collection from lithium plasma flow

International Nuclear Information System (INIS)

Karchevsky, A.I.; Laz'ko, V.S.; Muromkin, Y.A.; Pashkovsky, V.G.; Ustinov, A.L.; Dolgolenko, D.A.

1994-01-01

In order to understand the physical processes concerned with the selective heating by ion cyclotron resonance and with the subsequent collection of heated particles, experiments were carried out with the extraction of lithium samples, enriched with 6 Li isotopes. Probe and integral extractors allow to collect enriched Li at the end of the selective heating region. Surface density distribution on the collector and local isotopic content of lithium are measured, as a function of the screen height and the retarding potential. Dependence of the collected amount of lithium and of its isotopic content on the value of the magnetic field is also measured. 4 figs., 2 tabs., 5 refs

Summary of the Effort to Use Active-induced Time Correlation Techniques to Measure the Enrichment of HEU

Energy Technology Data Exchange (ETDEWEB)

McConchie, Seth M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Crye, Jason Michael [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Pena, Kirsten [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States); Sword, Eric [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mihalczo, John T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-09-30

This document summarizes the effort to use active-induced time correlation techniques to measure the enrichment of bulk quantities of enriched uranium. In summary, these techniques use an external source to initiate fission chains, and the time distribution of the detected fission chain neutrons is sensitive to the fissile material enrichment. The number of neutrons emitted from a chain is driven by the multiplication of the item, and the enrichment is closely coupled to the multiplication of the item. As the enrichment increases (decreases), the multiplication increases (decreases) if the geometry is held constant. The time distribution of fission chain neutrons is a complex function of the enrichment and material configuration. The enrichment contributes to the probability of a subsequent fission in a chain via the likelihood of fissioning on an even-numbered isotope versus an odd-numbered isotope. The material configuration contributes to the same probability via solid angle effects for neutrons inducing subsequent fissions and the presence of any moderating material. To simplify the ability to accurately measure the enrichment, an associated particle imaging (API) D-T neutron generator and an array of plastic scintillators are used to simultaneously image the item and detect the fission chain neutrons. The image is used to significantly limit the space of enrichment and material configuration and enable the enrichment to be determined unambiguously.

Proteomic analysis of phosphoproteins sensitive to a phosphatidylinositol 3-kinase inhibitor, ZSTK474, by using SELDI-TOF MS

Directory of Open Access Journals (Sweden)

Yamori Takao

2009-03-01

Full Text Available Abstract Background Phosphoproteins play important roles in a vast series of biological processes. Recent proteomic technologies offer the comprehensive analyses of phosphoproteins. Recently, we demonstrated that surface-enhanced laser desorption/ionization time of flight mass (SELDI-TOF MS would detect phosphoproteins quantitatively, which was a new application of SELDI-TOF MS. Results We combined immobilized metal affinity chromatography (IMAC with SELDI-TOF MS. After SELDI-TOF MS analysis of IMAC-enrichment phosphoproteins from A549 cancer cells, a series of protein peaks at 12.9, 12.8, 12.7 and 12.6 kDa was obtained in a mass spectrum. The peak intensities of these proteins decreased after a phosphatase treatment and, interestingly, they also decreased when the cells were pre-treated with a novel phosphatidylinositol 3-kinase (PI3K inhibitor, ZSTK474, suggesting that these proteins were ZSTK474-sensitive phosphoproteins. Identity of the phosphoproteins, which were predicted as the multi-phosphorylated forms of 4E-binding protein 1 (4E-BP1 with the aid of TagIdent algorithm, was confirmed by immunoprecipitation and subsequent SELDI-TOF MS analysis. 4E-BP1 is a downstream component of the PI3K/Akt/mTOR pathway and it regulates protein synthesis. We also investigated the effect of ZSTK474 on 4E-BP1 phosphorylation using phospho-specific antibodies. ZSTK474, which have little inhibitory activity for mTOR, inhibited phosphorylation of Ser65, Thr70 and Thr37/46 in 4E-BP1. In contrast, rapamycin, an inhibitor of mTOR, blocked phosphorylation only of Ser65 and Thr70. These results suggest that ZSTK474 and rapamycin inhibited the phosphorylation of 4E-BP1 in a different manner. Conclusion We identified a group of ZSTK474-sensitive phosphoproteins as the multi-phosphorylated form of 4E-BP1 by combining IMAC, SELDI-TOF MS and antibodies.

Safeguarding uranium enrichment facilities. Review and analysis of the status of safeguards technology for uranium enrichment facilities

International Nuclear Information System (INIS)

1977-09-01

The objective of this paper is to examine critically the diversion potential at uranium enrichment facilities and to outline a basic safeguards strategy which counters all identified hazards as completely as possible yet with a minimum of non-essential redundancy. Where existing technology does not appear to be adequate for effective safeguards, the limitations are examined, and suggestions for further R and D effort are made. Parts of this report are generally applicable to all currently known enrichment processes, while other parts are specifically directed toward facilities based on the gas centrifuge process. It is hoped that additional sections discussing a safeguards strategy for gas diffusion facilities can be added later. It should be emphasized that this is a technical report, and does not reflect any legal positions. The safeguards strategy and subsequent inspection procedures are intended as guidelines, not as negotiating positions

Enrichment and identification of polycyclic aromatic compound-degrading bacteria enriched from sediment samples.

Science.gov (United States)

Long, Rachel M; Lappin-Scott, Hilary M; Stevens, Jamie R

2009-07-01

The degradation of polycyclic aromatic compounds (PACs) has been widely studied. Knowledge of the degradation of PACs by microbial populations can be utilized in the remediation of contaminated sites. To isolate and identify PAC-degrading bacteria for potential use in future bioremediation programmes, we established a series of PAC enrichments under the same experimental conditions from a single sediment sample taken from a highly polluted estuarine site. Enrichment cultures were established using the pollutants: anthracene, phenanthrene and dibenzothiophene as a sole carbon source. The shift in microbial community structure on each of these carbon sources was monitored by analysis of a time series of samples from each culture using 16S rRNA polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Significantly, our findings demonstrate that shifts in the constituent species within each degradative community are directly attributable to enrichment with different PACs. Subsequently, we characterized the microorganisms comprising the degradative communities within each enrichment using 16S rRNA sequence data. Our findings demonstrate that the ability to degrade PACs is present in five divisions of the Proteobacteria and Actinobacteria. By determining the precise identity of the PAC-degrading bacterial species isolated from a single sediment sample, and by comparing our findings with previously published research, we demonstrate how bacteria with similar PAC degrading capabilities and 16S rRNA signatures are found in similarly polluted environments in geographically very distant locations, e.g., China, Italy, Japan and Hawaii. Such a finding suggests that geographical barriers do not limit the distribution of key PAC-degrading bacteria; this finding is in accordance with the Baas-Becking hypothesis "everything is everywhere; the environment selects" and may have significant consequences for the global distribution of PAC-degrading bacteria and

The design of an automated electrolytic enrichment apparatus for tritium

Energy Technology Data Exchange (ETDEWEB)

Myers, J.L.

1994-12-01

The Radiation Analytical Sciences Section at Laboratory at Lawrence Livermore National Laboratory performs analysis of low-level tritium concentrations in various natural water samples from the Tri-Valley Area, DOE Nevada Test Site, Site 300 in Tracy, CA, and other various places around the world. Low levels of tritium, a radioactive isotope of hydrogen, which is pre-concentrated in the RAS laboratory using an electrolytic enrichment apparatus. Later these enriched waters are analyzed by liquid scintillation counting to determine the activity of tritium. The enrichment procedure and the subsequent purification process by vacuum distillation are currently undertaken manually, hence being highly labor-intensive. The whole process typically takes about 2 to 3 weeks to complete a batch of 30 samples, with a dedicated personnel operating the process. The goal is to automate the entire process, specifically having the operation PC-LabVIEW{trademark} controlled with real-time monitoring capability. My involvement was in the design and fabrication of a prototypical automated electrolytic enrichment cell. Work will be done on optimizing the electrolytic process by assessing the different parameters of the enrichment procedure. Hardware and software development have also been an integral component of this project.

Inventory control through gamma spectrometry at the enriched uranium laboratory

International Nuclear Information System (INIS)

Vicens, H.E.; Korob, R.O.; Goldschmidt, A.E.

1987-01-01

The enriched uranium laboratory processes alternatively uranium 90% and 20% enriched in U-235. The control of the isotopic composition of lots is made through mass spectrometry. In the laboratory operation wastes of both enrichments are generated and the recovery is performed with a time delay. To strengthen the administrative controls, avoid errors related to personnel replacement and/or deferred operations, it seemed suitable to adjust the gamma spectrometry as a fast, simple and available method to determine the enrichment. The laboratory work includes a wet and a dry process. The waste recovery necessarily involves the handling of liquid samples. For this reason, it was decided to determine the calibration curve for uranyl nitrate samples of fixed concentration and geometry. The samples were prepared from material purified through double precipitation of uranium peroxide and subsequent ignition to U 3 O 8 in platinum crucible, in tubular oven during 8 hours at 720 deg C. The preparation of samples, the measurement description, the discussion of results and the analysis of errors due to the presence of insoluble material and concentration changes are included. (Author)

Method of producing deuterium-oxide-enriched water

International Nuclear Information System (INIS)

Mandel, H.

1976-01-01

A method and apparatus for producing deuterium-oxide-enriched water (e.g., as a source of deuterium-rich gas mixtures) are disclosed wherein the multiplicity of individual cooling cycles of a power plant are connected in replenishment cascade so that fresh feed water with a naturally occurring level of deuterium oxide is supplied to replace the vaporization losses, sludge losses and withdrawn portion of water in a first cooling cycle, the withdrawn water being fed as the feed water to the subsequent cooling cycle or stage and serving as the sole feed-water input to the latter. At the end of the replenishment-cascade system, the withdrawn water has a high concentration of deuterium oxide and may serve as a source of water for the production of heavy water or deuterium-enriched gas by conventional methods of removing deuterium oxide or deuterium from the deuterium-oxide-enriched water. Each cooling cycle may form part of a thermal or nuclear power plant in which a turbine is driven by part of the energy and air-cooling of the water takes place in the atmosphere, e.g., in a cooling tower

Modular enrichment measurement system for in-situ enrichment assay

International Nuclear Information System (INIS)

Stewart, J.P.

1976-01-01

A modular enrichment measurement system has been designed and is in operation within General Electric's Nuclear Fuel Fabrication Facility for the in-situ enrichment assay of uranium-bearing materials in process containers. This enrichment assay system, which is based on the ''enrichment meter'' concept, is an integral part of the site's enrichment control program and is used in the in-situ assay of the enrichment of uranium dioxide (UO 2 ) powder in process containers (five gallon pails). The assay system utilizes a commercially available modular counting system and a collimnator designed for compatability with process container transport lines and ease of operator access. The system has been upgraded to include a microprocessor-based controller to perform system operation functions and to provide data acquisition and processing functions. Standards have been fabricated and qualified for the enrichment assay of several types of uranium-bearing materials, including UO 2 powders. The assay system has performed in excess of 20,000 enrichment verification measurements annually and has significantly contributed to the facility's enrichment control program

Enrichment of anaerobic syngas-converting bacteria from thermophilic bioreactor sludge.

Science.gov (United States)

Alves, Joana I; Stams, Alfons J M; Plugge, Caroline M; Alves, M Madalena; Sousa, Diana Z

2013-12-01

Thermophilic (55 °C) anaerobic microbial communities were enriched with a synthetic syngas mixture (composed of CO, H2 , and CO2 ) or with CO alone. Cultures T-Syn and T-CO were incubated and successively transferred with syngas (16 transfers) or CO (9 transfers), respectively, with increasing CO partial pressures from 0.09 to 0.88 bar. Culture T-Syn, after 4 successive transfers with syngas, was also incubated with CO and subsequently transferred (9 transfers) with solely this substrate - cultures T-Syn-CO. Incubation with syngas and CO caused a rapid decrease in the microbial diversity of the anaerobic consortium. T-Syn and T-Syn-CO showed identical microbial composition and were dominated by Desulfotomaculum and Caloribacterium species. Incubation initiated with CO resulted in the enrichment of bacteria from the genera Thermincola and Thermoanaerobacter. Methane was detected in the first two to three transfers of T-Syn, but production ceased afterward. Acetate was the main product formed by T-Syn and T-Syn-CO. Enriched T-CO cultures showed a two-phase conversion, in which H2 was formed first and then converted to acetate. This research provides insight into how thermophilic anaerobic communities develop using syngas/CO as sole energy and carbon source can be steered for specific end products and subsequent microbial synthesis of chemicals. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

The world enrichment market

International Nuclear Information System (INIS)

Gunter, L.; McCants, C.; Rutkowski, E.

1991-01-01

The enrichment market can be divided into two periods: the near-term market (1991 to 1995) and the long-term market (1995 and beyond). The near-term market is characterized by limited unfilled requirements of 4% per year, to be supplied by national stockpiles and excess inventories. This low-cost material will be drawn down by about 1993, causing a subsequent price rise. As the price rises, primary supplier activity is expected to increase. In the near-term, two contracting activities are apparent: spot; and intermediate-term. The current spot market is expected to last until available low cost inventories are drawn down. Recently, in attempts to gain market share, suppliers have offered attractively priced intermediate-term (3 year) contracts for 1996 to 1998. While a small spot market will continue after 1995, it is anticipated that utilities will prefer a mix of medium- and long-term (5 to 10 year) contracts from primary suppliers for most of their enrichment requirements. As national stockpiles and utility inventories are consumed, low-cost supply available to the spot market is expected to diminish. Consequently, with little low-cost supply available, the only apparent source of material will be from primary suppliers, and the resulting competition over market share is expected to be intense. (author)

Growth Rates of Bacillus Species Probiotics using Various Enrichment Media

Directory of Open Access Journals (Sweden)

Maryam Poormontaseri

2017-03-01

Full Text Available Background: Probiotics are well-known as valuable functional foods to promote specific health benefits to consumers. Some Bacillus bacteria have been recently considered as probiotic and food additives. We aimed to investigate the growing rate of probiotic B. subtilis and B. coagulans using several enrichment media incubated at 37 °C for 24 hours. Methods: Various enrichment media including nutrient broth (NB, tryptic soy broth (TSB, double strength TSB, Mueller Hinton broth (MH, brain-heart infusion broth (BHIB, de Man, Rogosa and Sharpe (MRS, and nutrient yeast extract salt medium (NYSM were used to enrich the probiotics and they were subsequently incubated for 18 h at 37 °C. The bacteria were then enumerated on TSA medium. Results: The results showed that B. subtilis ATCC 6633, B. subtilis PY79, and B. coagulans developed in TSB, double strength TBS, TSB yeast extract, BHIB and NYSM, respectively. Moreover, the formulas were achieved based on the optical density curve and the number of bacteria. Conclusion: Considering that the probiotics are significantly employed as food supplements, it is essential to identify appropriate enrichment media to proliferate these beneficial bacteria.

Selecting Sample Preparation Workflows for Mass Spectrometry-Based Proteomic and Phosphoproteomic Analysis of Patient Samples with Acute Myeloid Leukemia.

Science.gov (United States)

Hernandez-Valladares, Maria; Aasebø, Elise; Selheim, Frode; Berven, Frode S; Bruserud, Øystein

2016-08-22

Global mass spectrometry (MS)-based proteomic and phosphoproteomic studies of acute myeloid leukemia (AML) biomarkers represent a powerful strategy to identify and confirm proteins and their phosphorylated modifications that could be applied in diagnosis and prognosis, as a support for individual treatment regimens and selection of patients for bone marrow transplant. MS-based studies require optimal and reproducible workflows that allow a satisfactory coverage of the proteome and its modifications. Preparation of samples for global MS analysis is a crucial step and it usually requires method testing, tuning and optimization. Different proteomic workflows that have been used to prepare AML patient samples for global MS analysis usually include a standard protein in-solution digestion procedure with a urea-based lysis buffer. The enrichment of phosphopeptides from AML patient samples has previously been carried out either with immobilized metal affinity chromatography (IMAC) or metal oxide affinity chromatography (MOAC). We have recently tested several methods of sample preparation for MS analysis of the AML proteome and phosphoproteome and introduced filter-aided sample preparation (FASP) as a superior methodology for the sensitive and reproducible generation of peptides from patient samples. FASP-prepared peptides can be further fractionated or IMAC-enriched for proteome or phosphoproteome analyses. Herein, we will review both in-solution and FASP-based sample preparation workflows and encourage the use of the latter for the highest protein and phosphorylation coverage and reproducibility.

Laser-induced photochemical enrichment of boron isotopes

International Nuclear Information System (INIS)

Freund, S.M.; Ritter, J.J.

1976-01-01

A boron trichloride starting material containing both boron-10 isotopes and boron-11 isotopes is selectively enriched in one or the other of these isotopes by a laser-induced photochemical method involving the reaction of laser-excited boron trichloride with either H 2 S or D 2 S. The method is carried out by subjecting a low pressure gaseous mixture of boron trichloride starting material and the sulfide to infrared radiation from a carbon dioxide TE laser. The wave length of the radiation is selected so as to selectively excite one or the other of boron-10 BCl 3 molecules or boron-11 BCl 3 molecules, thereby making them preferentially more reactive with the sulfide. The laser-induced reaction produces both a boron-containing solid phase reaction product and a gaseous phase containing mostly unreacted BCl 3 and small amounts of sulfhydroboranes. Pure boron trichloride selectively enriched in one of the isotopes is recovered as the primary product of the method from the gaseous phase by a multi-step recovery procedure. Pure boron trichloride enriched in the other isotope is recovered as a secondary product of the method by the subsequent chlorination of the solid phase reaction product followed by separation of BCl 3 from the mixture of gaseous products resulting from the chlorination

Uranium enrichment

International Nuclear Information System (INIS)

1990-01-01

This report looks at the following issues: How much Soviet uranium ore and enriched uranium are imported into the United States and what is the extent to which utilities flag swap to disguise these purchases? What are the U.S.S.R.'s enriched uranium trading practices? To what extent are utilities required to return used fuel to the Soviet Union as part of the enriched uranium sales agreement? Why have U.S. utilities ended their contracts to buy enrichment services from DOE?

Gas-phase UF6 enrichment monitor for enrichment plant safeguards

International Nuclear Information System (INIS)

Strittmatter, R.B.; Tape, J.W.

1980-03-01

An in-line enrichment monitor is being developed to provide real-time enrichment data for the gas-phase UF 6 feed stream of an enrichment plant. The nondestructive gamma-ray assay method can be used to determine the enrichment of natural UF 6 with a relative precision of better than 1% for a wide range of pressures

Enrichment Wastes' Processing of Manganiferous Ores with the Use of Mechanochemical Methods

Science.gov (United States)

Kubekova, Sholpan N.; Kapralova, Viktoria I.; Ibraimova, Gulnur T.; Batyrbayeva, Aigul A.

2016-01-01

The aim of the research is the study of the chemical and phase composition of enrichment wastes of manganiferous ore in Ushkatyn-III deposit and the synthesis of new materials by mechanochemical activation and subsequent heat treatment of the mechanical activation products. The use of XFA, infrared spectroscopy and electron probe microanalysis…

Retro-Nasal Aroma Release Is Correlated with Variations in the In-Mouth Air Cavity Volume after Empty Deglutition

Science.gov (United States)

Mishellany-Dutour, Anne; Woda, Alain; Labouré, Hélène; Bourdiol, Pierre; Lachaze, Pauline; Guichard, Elisabeth; Feron, Gilles

2012-01-01

We hypothesized that interindividual differences in motor activities during chewing and/or swallowing were determining factors for the transfer of volatile aroma from the in-mouth air cavity (IMAC) toward the olfactory mucosa. In our first experiment, we looked for changes in IMAC volume after saliva deglutition in 12 healthy subjects. The mean IMAC volume was measured after empty deglutition using an acoustic pharyngometer device. Based on the time course of the IMAC volume after swallowing, we discerned two groups of subjects. The first group displayed a small, constant IMAC volume (2.26 mL ±0.62) that corresponded to a high tongue position. The second group displayed a progressive increase in IMAC (from 6.82 mL ±2.37 to 22.82 mL ±3.04) that corresponded to a progressive lowering of the tongue to its resting position. In our second experiment, we investigated the relationship between IMAC volume changes after deglutition and the level of aroma release at the nostril. For this purpose, the release of menthone was measured at the nostril level in 25 subjects who consumed similar amounts of a mint tablet. The subjects were separated into two groups corresponding to two levels of menthone release: high (H) and low (L). The mean volume of IMAC was measured during and after empty deglutition. Group H displayed a small, constant amplitude of IMAC volume change after deglutition, while Group L displayed a progressive increase in IMAC. It is likely that Group H continuously released the aroma through the veloglossal isthmus as the mint was consumed, while Group L trapped the aroma in the oral cavity and then released it into the nasal cavity upon swallowing. These results show that the in vivo aroma release profile in humans depends closely on the different motor patterns at work during empty deglutition. PMID:22815986

Retro-nasal aroma release is correlated with variations in the in-mouth air cavity volume after empty deglutition.

Directory of Open Access Journals (Sweden)

Anne Mishellany-Dutour

Full Text Available We hypothesized that interindividual differences in motor activities during chewing and/or swallowing were determining factors for the transfer of volatile aroma from the in-mouth air cavity (IMAC toward the olfactory mucosa. In our first experiment, we looked for changes in IMAC volume after saliva deglutition in 12 healthy subjects. The mean IMAC volume was measured after empty deglutition using an acoustic pharyngometer device. Based on the time course of the IMAC volume after swallowing, we discerned two groups of subjects. The first group displayed a small, constant IMAC volume (2.26 mL ±0.62 that corresponded to a high tongue position. The second group displayed a progressive increase in IMAC (from 6.82 mL ±2.37 to 22.82 mL ±3.04 that corresponded to a progressive lowering of the tongue to its resting position. In our second experiment, we investigated the relationship between IMAC volume changes after deglutition and the level of aroma release at the nostril. For this purpose, the release of menthone was measured at the nostril level in 25 subjects who consumed similar amounts of a mint tablet. The subjects were separated into two groups corresponding to two levels of menthone release: high (H and low (L. The mean volume of IMAC was measured during and after empty deglutition. Group H displayed a small, constant amplitude of IMAC volume change after deglutition, while Group L displayed a progressive increase in IMAC. It is likely that Group H continuously released the aroma through the veloglossal isthmus as the mint was consumed, while Group L trapped the aroma in the oral cavity and then released it into the nasal cavity upon swallowing. These results show that the in vivo aroma release profile in humans depends closely on the different motor patterns at work during empty deglutition.

Uranium enrichment

International Nuclear Information System (INIS)

Rae, H.K.; Melvin, J.G.

1988-06-01

Canada is the world's largest producer and exporter of uranium, most of which is enriched elsewhere for use as fuel in LWRs. The feasibility of a Canadian uranium-enrichment enterprise is therefore a perennial question. Recent developments in uranium-enrichment technology, and their likely impacts on separative work supply and demand, suggest an opportunity window for Canadian entry into this international market. The Canadian opportunity results from three particular impacts of the new technologies: 1) the bulk of the world's uranium-enrichment capacity is in gaseous diffusion plants which, because of their large requirements for electricity (more than 2000 kW·h per SWU), are vulnerable to competition from the new processes; 2) the decline in enrichment costs increases the economic incentive for the use of slightly-enriched uranium (SEU) fuel in CANDU reactors, thus creating a potential Canadian market; and 3) the new processes allow economic operation on a much smaller scale, which drastically reduces the investment required for market entry and is comparable with the potential Canadian SEU requirement. The opportunity is not open-ended. By the end of the century the enrichment supply industry will have adapted to the new processes and long-term customer/supplier relationships will have been established. In order to seize the opportunity, Canada must become a credible supplier during this century

An Internal Standard for Assessing Phosphopeptide Recovery from Metal Ion/Oxide Enrichment Strategies

Science.gov (United States)

Paulo, Joao A.; Navarrete-Perea, Jose; Erickson, Alison R.; Knott, Jeffrey; Gygi, Steven P.

2018-04-01

Phosphorylation-mediated signaling pathways have major implications in cellular regulation and disease. However, proteins with roles in these pathways are frequently less abundant and phosphorylation is often sub-stoichiometric. As such, the efficient enrichment, and subsequent recovery of phosphorylated peptides, is vital. Mass spectrometry-based proteomics is a well-established approach for quantifying thousands of phosphorylation events in a single experiment. We designed a peptide internal standard-based assay directed toward sample preparation strategies for mass spectrometry analysis to understand better phosphopeptide recovery from enrichment strategies. We coupled mass-differential tandem mass tag (mTMT) reagents (specifically, TMTzero and TMTsuper-heavy), nine mass spectrometry-amenable phosphopeptides (phos9), and peak area measurements from extracted ion chromatograms to determine phosphopeptide recovery. We showcase this mTMT/phos9 recovery assay by evaluating three phosphopeptide enrichment workflows. Our assay provides data on the recovery of phosphopeptides, which complement other metrics, namely the number of identified phosphopeptides and enrichment specificity. Our mTMT/phos9 assay is applicable to any enrichment protocol in a typical experimental workflow irrespective of sample origin or labeling strategy. [Figure not available: see fulltext.

Image management and communication in patient care: perspectives on implementation and impact.

Science.gov (United States)

Greberman, M; Mun, S K

1989-02-01

Image management and communication (IMAC) systems are automated and integrated systems that capture digital medical images and related patient information and transmit them electronically, display them for interpretation, and store them for future retrieval. The IMAC system concept includes images and relevant information from all clinical sources. The First International Conference on Image Management and Communication in Patient Care (IMAC 89) provides a forum for expert presentations, poster sessions, and discussion and debate among all attendees interested in the implementation and impact of IMAC systems. Plenary sessions provide an international perspective and explore the role of image-based information in patient care, approaches to improved IMAC systems, current technical barriers, quality of care issues, evaluation approaches, and scenarios for the future. Invited participants are from North America, Europe, Japan, Australia, and the WHO. Conference organizers are working with numerous professional organizations and representatives of meetings which focus on IMAC-related technology to complement, and not duplicate, the contribution of other groups.

Advanced enrichment techniques

International Nuclear Information System (INIS)

Johnson, A.

1988-01-01

BNFL is in a unique position in that it has commercial experience of diffusion enrichment, and of centrifuge enrichment through its associate company Urenco. In addition BNFL is developing laser enrichment techniques as part of a UK development programme in this area. The paper describes the development programme which led to the introduction of competitive centrifuge enrichment technology by Urenco and discusses the areas where improvements have and will continue to be made in the centrifuge process. It also describes the laser development programme currently being undertaken in the UK. The paper concludes by discussing the relative merits of the various methods of uranium enrichment, with particular reference to the enrichment market likely to obtain over the rest of the century

Advanced enrichment techniques

International Nuclear Information System (INIS)

Johnson, A.

1987-01-01

BNFL is in a unique position in that it has commercial experience of diffusion enrichment, and of centrifuge enrichment through its associate company Urenco. In addition BNFL is developing laser enrichment techniques as part of a UK development programme in this area. The paper describes the development programme which led to the introduction of competitive centrifuge enrichment technology by Urenco and discusses the areas where improvements have and will continue to be made in the centrifuge process. It also describes the laser development programme currently being undertaken in the UK. The paper concludes by discussing the relative merits of the various methods of uranium enrichment, with particular reference to the enrichment market likely to obtain over the rest of the century. (author)

Juvenile psittacine environmental enrichment.

Science.gov (United States)

Simone-Freilicher, Elisabeth; Rupley, Agnes E

2015-05-01

Environmental enrichment is of great import to the emotional, intellectual, and physical development of the juvenile psittacine and their success in the human home environment. Five major types of enrichment include social, occupational, physical, sensory, and nutritional. Occupational enrichment includes exercise and psychological enrichment. Physical enrichment includes the cage and accessories and the external home environment. Sensory enrichment may be visual, auditory, tactile, olfactory, or taste oriented. Nutritional enrichment includes variations in appearance, type, and frequency of diet, and treats, novelty, and foraging. Two phases of the preadult period deserve special enrichment considerations: the development of autonomy and puberty. Copyright © 2015 Elsevier Inc. All rights reserved.

Uranium enrichment

International Nuclear Information System (INIS)

1989-01-01

GAO was asked to address several questions concerning a number of proposed uranium enrichment bills introduced during the 100th Congress. The bill would have restructured the Department of Energy's uranium enrichment program as a government corporation to allow it to compete more effectively in the domestic and international markets. Some of GAO's findings discussed are: uranium market experts believe and existing market models show that the proposed DOE purchase of a $750 million of uranium from domestic producers may not significantly increase production because of large producer-held inventories; excess uranium enrichment production capacity exists throughout the world; therefore, foreign producers are expected to compete heavily in the United States throughout the 1990s as utilities' contracts with DOE expire; and according to a 1988 agreement between DOE's Offices of Nuclear Energy and Defense Programs, enrichment decommissioning costs, estimated to total $3.6 billion for planning purposes, will be shared by the commercial enrichment program and the government

Isotope enrichment

International Nuclear Information System (INIS)

Lydtin, H-J.; Wilden, R.J.; Severin, P.J.W.

1978-01-01

The isotope enrichment method described is based on the recognition that, owing to mass diffusion and thermal diffusion in the conversion of substances at a heated substrate while depositing an element or compound onto the substrate, enrichment of the element, or a compound of the element, with a lighter isotope will occur. The cycle is repeated for as many times as is necessary to obtain the degree of enrichment required

Effects of Environmental Enrichment on the Fertility and Fecundity of Zebrafish (Danio rerio).

Science.gov (United States)

Wafer, Lemnique N; Jensen, V Behrana; Whitney, Jesse C; Gomez, Thomas H; Flores, Rene; Goodwin, Bradford S

2016-01-01

Zebrafish (Danio rerio) are a popular vertebrate model in biomedical research, but information describing the effects of environmental enrichment on fertility and fecundity of zebrafish is sparse. In the current study, 18 breeding pairs were placed in divided 1.5-L breeding tanks containing 1 of 3 enrichment conditions: plastic grass (n = 6), plastic leaves (n = 6), or no enrichment (n = 6, control). The pairs were allowed to spawn for 3 h the next day, after which eggs were counted and breeding pairs were returned to holding tanks for use in subsequent sessions. Spawning sessions were repeated at 7-d intervals until the completion of 9 trials, with pairs rotating to a different condition at each interval. Total egg count (mean ± SEM) after 3 h was greater for zebrafish spawning in the grass environment (48.0 ± 7.7 eggs) than in the leaf or control environments (29.4 ± 5.3 and 20.4 ± 3.7 eggs, respectively). An interaction emerged between enrichment type and the age of the spawning pair on the number of fry at 6 d postfertilization (dpf). Initially, more fry were obtained from 110- and 160-dpf pairs with the grass enrichment, but from 173- and 180-dpf pairs there were more obtained with leaf enrichment than grass. A separate experiment showed that enrichment type did not have an effect on fry survivability. Overall, our data indicates that, under certain conditions, zebrafish fertility and fecundity are greater in a breeding tank containing environmental enrichment than in a bare tank.

New generation enrichment monitoring technology for gas centrifuge enrichment plants

International Nuclear Information System (INIS)

Ianakiev, Kiril D.; Alexandrov, Boian S.; Boyer, Brian D.; Hill, Thomas R.; Macarthur, Duncan W.; Marks, Thomas; Moss, Calvin E.; Sheppard, Gregory A.; Swinhoe, Martyn T.

2008-01-01

The continuous enrichment monitor, developed and fielded in the 1990s by the International Atomic Energy Agency, provided a go-no-go capability to distinguish between UF 6 containing low enriched (approximately 4% 235 U) and highly enriched (above 20% 235 U) uranium. This instrument used the 22-keV line from a 109 Cd source as a transmission source to achieve a high sensitivity to the UF 6 gas absorption. The 1.27-yr half-life required that the source be periodically replaced and the instrument recalibrated. The instrument's functionality and accuracy were limited by the fact that measured gas density and gas pressure were treated as confidential facility information. The modern safeguarding of a gas centrifuge enrichment plant producing low-enriched UF 6 product aims toward a more quantitative flow and enrichment monitoring concept that sets new standards for accuracy stability, and confidence. An instrument must be accurate enough to detect the diversion of a significant quantity of material, have virtually zero false alarms, and protect the operator's proprietary process information. We discuss a new concept for advanced gas enrichment assay measurement technology. This design concept eliminates the need for the periodic replacement of a radioactive source as well as the need for maintenance by experts. Some initial experimental results will be presented.

Selecting Sample Preparation Workflows for Mass Spectrometry-Based Proteomic and Phosphoproteomic Analysis of Patient Samples with Acute Myeloid Leukemia

Directory of Open Access Journals (Sweden)

Maria Hernandez-Valladares

2016-08-01

Full Text Available Global mass spectrometry (MS-based proteomic and phosphoproteomic studies of acute myeloid leukemia (AML biomarkers represent a powerful strategy to identify and confirm proteins and their phosphorylated modifications that could be applied in diagnosis and prognosis, as a support for individual treatment regimens and selection of patients for bone marrow transplant. MS-based studies require optimal and reproducible workflows that allow a satisfactory coverage of the proteome and its modifications. Preparation of samples for global MS analysis is a crucial step and it usually requires method testing, tuning and optimization. Different proteomic workflows that have been used to prepare AML patient samples for global MS analysis usually include a standard protein in-solution digestion procedure with a urea-based lysis buffer. The enrichment of phosphopeptides from AML patient samples has previously been carried out either with immobilized metal affinity chromatography (IMAC or metal oxide affinity chromatography (MOAC. We have recently tested several methods of sample preparation for MS analysis of the AML proteome and phosphoproteome and introduced filter-aided sample preparation (FASP as a superior methodology for the sensitive and reproducible generation of peptides from patient samples. FASP-prepared peptides can be further fractionated or IMAC-enriched for proteome or phosphoproteome analyses. Herein, we will review both in-solution and FASP-based sample preparation workflows and encourage the use of the latter for the highest protein and phosphorylation coverage and reproducibility.

Uranium enrichment plans

International Nuclear Information System (INIS)

Thomas, D.C.; Gagne, R.W.

1978-01-01

The following topics are covered: the status of the Government's existing uranium enrichment services contracts, natural uranium requirements based on the latest contract information, uncertainty in predicting natural uranium requirements based on uranium enrichment contracts, and domestic and foreign demand assumed in enrichment planning

Quantitative phosphoproteomics applied to the yeast pheromone signaling pathway

DEFF Research Database (Denmark)

Gruhler, Albrecht; Olsen, Jesper Velgaard; Mohammed, Shabaz

2005-01-01

of a detailed molecular view of complex biological processes. We present a quantitative modification-specific proteomic approach that combines stable isotope labeling by amino acids in cell culture (SILAC) for quantitation with IMAC for phosphopeptide enrichment and three stages of mass spectrometry (MS....... Phosphopeptide fractions were analyzed by LC-MS using a linear ion trap-Fourier transform ion cyclotron resonance mass spectrometer. MS/MS and neutral loss-directed MS/MS/MS analysis allowed detection and sequencing of phosphopeptides with exceptional accuracy and specificity. Of more than 700 identified...

Other enrichment related contracts

International Nuclear Information System (INIS)

Hall, J.C.

1978-01-01

In addition to long-term enrichment contracts, DOE has other types of contracts: (1) short-term, fixed-commitment enrichment contract; (2) emergency sales agreement for enriched uranium; (3) feed material lease agreement; (4) enriched uranium storage agreement; and (5) feed material usage agreement

Fish burger enriched by olive oil industrial by-product.

Science.gov (United States)

Cedola, Annamaria; Cardinali, Angela; Del Nobile, Matteo Alessandro; Conte, Amalia

2017-07-01

Oil industry produces large volume of waste, which represents a disposal and a potential environmental pollution problem. Nevertheless, they are also promising sources of compounds that can be recovered and used as valuable substances. The aim of this work is to exploit solid olive by-products, in particular dry olive paste flour (DOPF) coming from Coratina cultivar, to enrich fish burger and enhance the quality characteristics. In particular, the addition of olive by-products leads to an increase of the phenolic content and the antioxidant activity; however, it also provokes a deterioration of sensory quality. Therefore, to balance quality and sensory characteristics of fish burgers, three subsequent phases have been carried out: first, the quality of DOPF in terms of phenolic compounds content and antioxidant activity has been assessed; afterward, DOPF has been properly added to fish burgers and, finally, the formulation of the enriched fish burgers has been optimized in order to improve the sensory quality. Results suggested that the enriched burgers with 10% DOPF showed considerable amounts of polyphenols and antioxidant activity, even though they are not very acceptable from the sensory point of view. Pre-treating DOPF by hydration/extraction with milk, significantly improved the burger sensory quality by reducing the concentration of bitter components.

Sequential enrichment of microbial population exhibiting enhanced biodegradation of crude oil

International Nuclear Information System (INIS)

Venkateswaran, Kasthuri; Harayama, Shigeaki.

1995-01-01

The distribution of oil-degrading bacteria in the coastal waters and sediments of Hokkaido, Japan, was surveyed. It was found that the potential of mixed microbial populations to degrade weathered crude oil was not confined to any ecological components (water or sediment) nor to the sampling stations. One microbial culture that was stable during repeated subculturing degraded 45% of the saturates and 20% of the aromatics present in crude oil in 10 days during the initial screening. The residual hydrocarbons in this culture were extracted by chloroform and dispersed in a fresh seawater-based medium and subsequently inoculated with microorganisms from the first culture. After full growth of the second culture, the residual hydrocarbons were extracted and dispersed in a fresh medium in which microorganisms from the second culture had been inoculated. This sequential process was carried out six times to enrich those microorganisms that grew on the recalcitrant components of crude oil. After repeated exposure of the residual crude oil to the enriched microorganisms, about 80% of the initially added crude oil was degraded. The cultures obtained after each enrichment cycle were kept, and the degradation of fresh crude oil by the enriched microorganisms was monitored. The degrading activity of the enriched cultures increased as the number of enrichment cycles increased. A microbial population that had been selected six times on the residual crude oil could degrade 70% of the saturates and 30% of the aromatics of crude oil, indicating that growth of a microbial population on residual crude oil improved its ability to biodegrade crude oil. 21 refs., 2 tabs., 7 figs

On-Line Enrichment Monitor for UF{sub 6} Gas Centrifuge Enrichment Plant

Energy Technology Data Exchange (ETDEWEB)

Ianakiev, K. D.; Boyer, B.; Favalli, A.; Goda, J. M.; Hill, T.; Keller, C.; Lombardi, M.; Paffett, M.; MacArthur, D. W.; McCluskey, C.; Moss, C. E.; Parker, R.; Smith, M. K.; Swinhoe, M. T. [Los Alamos National Laboratory, Los Alamos (United States)

2012-06-15

This paper is a continuation of the Advanced Enrichment Monitoring Technology for UF{sub 6} Gas Centrifuge Enrichment Plant (GCEP) work, presented in the 2010 IAEA Safeguards Symposium. Here we will present the system architecture for a planned side-by-side field trial test of passive (186-keV line spectroscopy and pressure-based correction for UF{sub 6} gas density) and active (186-keV line spectroscopy and transmission measurement based correction for UF{sub 6} gas density) enrichment monitoring systems in URENCO's enrichment plant in Capenhurst. Because the pressure and transmission measurements of UF{sub 6} are complementary, additional information on the importance of the presence of light gases and the UF{sub 6} gas temperature can be obtained by cross-correlation between simultaneous measurements of transmission, pressure and 186-keV intensity. We will discuss the calibration issues and performance in the context of accurate, on-line enrichment measurement. It is hoped that a simple and accurate on-line enrichment monitor can be built using the UF{sub 6} gas pressure provided by the Operator, based on online mass spectrometer calibration, assuming a negligible (a small fraction of percent) contribution of wall deposits. Unaccounted-for wall deposits present at the initial calibration will lead to unwanted sensitivity to changes in theUF{sub 6} gas pressure and thus to error in the enrichment results. Because the accumulated deposits in the cascade header pipe have been identified as an issue for Go/No Go measurements with the Cascade Header Enrichment Monitor (CHEM) and Continuous Enrichment Monitor (CEMO), it is important to explore their effect. Therefore we present the expected uncertainty on enrichment measurements obtained by propagating the errors introduced by deposits, gas density, etc. and will discuss the options for a deposit correction during initial calibration of an On-Line Enrichment Monitor (OLEM).

Uranium Enrichment, an overview

International Nuclear Information System (INIS)

Coates, J.H.

1994-01-01

This general presentation on uranium enrichment will be followed by lectures on more specific topics including descriptions of enrichment processes and assessments of the prevailing commercial and industrial situations. I shall therefore avoid as much as possible duplications with these other lectures, and rather dwell on: some theoretical aspects of enrichment in general, underlying the differences between statistical and selective processes, a review and comparison between enrichment processes, remarks of general order regarding applications, the proliferation potential of enrichment. It is noteworthy that enrichment: may occur twice in the LWR fuel cycle: first by enriching natural uranium, second by reenriching uranium recovered from reprocessing, must meet LWR requirements, and in particular higher assays required by high burn up fuel elements, bears on the structure of the entire front part of the fuel cycle, namely in the conversion/reconversion steps only involving UF 6 for the moment. (author). tabs., figs., 4 refs

A Targeted Enrichment Strategy for Massively Parallel Sequencing of Angiosperm Plastid Genomes

Directory of Open Access Journals (Sweden)

Gregory W. Stull

2013-02-01

Full Text Available Premise of the study: We explored a targeted enrichment strategy to facilitate rapid and low-cost next-generation sequencing (NGS of numerous complete plastid genomes from across the phylogenetic breadth of angiosperms. Methods and Results: A custom RNA probe set including the complete sequences of 22 previously sequenced eudicot plastomes was designed to facilitate hybridization-based targeted enrichment of eudicot plastid genomes. Using this probe set and an Agilent SureSelect targeted enrichment kit, we conducted an enrichment experiment including 24 angiosperms (22 eudicots, two monocots, which were subsequently sequenced on a single lane of the Illumina GAIIx with single-end, 100-bp reads. This approach yielded nearly complete to complete plastid genomes with exceptionally high coverage (mean coverage: 717×, even for the two monocots. Conclusions: Our enrichment experiment was highly successful even though many aspects of the capture process employed were suboptimal. Hence, significant improvements to this methodology are feasible. With this general approach and probe set, it should be possible to sequence more than 300 essentially complete plastid genomes in a single Illumina GAIIx lane (achieving 50× mean coverage. However, given the complications of pooling numerous samples for multiplex sequencing and the limited number of barcodes (e.g., 96 available in commercial kits, we recommend 96 samples as a current practical maximum for multiplex plastome sequencing. This high-throughput approach should facilitate large-scale plastid genome sequencing at any level of phylogenetic diversity in angiosperms.

Uranium enrichment

International Nuclear Information System (INIS)

Mohrhauer, H.

1982-01-01

The separation of uranium isotopes in order to enrich the fuel for light water reactors with the light isotope U-235 is an important part of the nuclear fuel cycle. After the basic principals of isotope separation the gaseous diffusion and the centrifuge process are explained. Both these techniques are employed on an industrial scale. In addition a short review is given on other enrichment techniques which have been demonstrated at least on a laboratory scale. After some remarks on the present situation on the enrichment market the progress in the development and the industrial exploitation of the gas centrifuge process by the trinational Urenco-Centec organisation is presented. (orig.)

United States uranium enrichment policies

International Nuclear Information System (INIS)

Roberts, R.W.

1977-01-01

ERDA's uranium enrichment program policies governing the manner in which ERDA's enrichment complex is being operated and expanded to meet customer requirements for separative work, research and development activities directed at providing technology alternatives for future enrichment capacity, and establishing the framework for additional domestic uranium enrichment capacity to meet the domestic and foreign nuclear industry's growing demand for enrichment services are considered. The ERDA enrichment complex consists of three gaseous diffusion plants located in Oak Ridge, Tennessee; Paducah, Kentucky; and Portsmouth, Ohio. Today, these plants provide uranium enrichment services for commercial nuclear power generation. These enrichment services are provided under contracts between the Government and the utility customers. ERDA's program involves a major pilot plant cascade, and pursues an advanced isotope separation technique for the late 1980's. That the United States must develop additional domestic uranium enrichment capacity is discussed

The use of titanium dioxide for selective enrichment of phosphorylated peptides

DEFF Research Database (Denmark)

Thingholm, Tine E.; Larsen, Martin R.

2016-01-01

acid (DHB), phthalic acid, lactic acid, or glycolic acid has been shown to improve selectivity significantly by reducing unspecific binding of non-phosphorylated peptides. The phosphopeptides bound to the TiO2 are subsequently eluted from the chromatographic material using an alkaline buffer. TiO2......Titanium dioxide (TiO2) has very high affinity for phosphopeptides and in recent years it has become one of the most popular methods for phosphopeptide enrichment from complex biological samples. Peptide loading onto TiO2 resin in a highly acidic environment in the presence of 2,5-dihydroxybenzoic...... chromatography is extremely tolerant towards most buffers used in biological experiments, highly robust and as such it has become the method of choice in large-scale phosphoproteomics. Here we describe a batch mode protocol for phosphopeptide enrichment using TiO2 chromatographic material followed by desalting...

Blueprint for domestic uranium enrichment

International Nuclear Information System (INIS)

1981-01-01

The AEC advisory committee on domestic production of uranium enrichment has studied for more than a year how to achieve the domestic enrichment of uranium by the construction and operation of a commercial enriching plant using centrifugal separation method, and the report was submitted to the Atomic Energy Commission on August 18, 1980. Japan has depended wholly on overseas services for her uranium enrichment needs, but the development of domestic enrichment has been carried on in parallel. The AEC decided to construct a uranium enrichment pilot plant using centrifuges, and it has been forwarded as a national project. The plant is operated by the Power Reactor and Nuclear Fuel Development Corp. since 1979. The capacity of the plant will be raised to approximately 75 ton SWU a year. The centrifuges already operated have provided the first delivery of fuel of about 1 ton for the ATR ''Fugen''. The demand-supply balance of uranium enrichment service, the significance of the domestic enrichment of uranium, the evaluation of uranium enrichment technology, the target for domestic enrichment plan, the measures to promote domestic uranium enrichment, and the promotion of the construction of a demonstration plant are reported. (Kako, I.)

78 FR 52170 - Proposed Subsequent Arrangement

Science.gov (United States)

2013-08-22

... 700,888 g of U.S.-origin natural uranium oxide material, containing 5,005 g of the isotope U-235 (0.71% enrichment) and 18,699,112 g of U.S.-origin enriched uranium oxide material, containing 654,386 g of the isotope U-235 (less than five percent enrichment) in the form of uranium fuel fabrication scrap from...

Derivatized graphitic nanofibres (GNF) as a new support material for mass spectrometric analysis of peptides and proteins.

Science.gov (United States)

Greiderer, Andreas; Rainer, Matthias; Najam-ul-Haq, Muhammad; Vallant, Rainer M; Huck, Christian W; Bonn, Günther K

2009-07-01

Graphitic nanofibres (GNFs), 100-200 nm in diameter and 5-20 microm in length have been modified in order to yield different affinities (Cu2+ and Fe3+ loaded immobilized metal affinity chromatography (IMAC) as well as cation and anion exchange materials) for the extraction of a range of biomolecules by their inherited hydrophobicity and the hydrophilic chemical functionalities, obtained by derivatization. Modified GNFs have for the first time been employed as carrier materials for protein profiling in material-enhanced laser desorption/ionization (MELDI) for the enrichment and screening of biofluids. For that purpose, the derivatized GNF materials have comprehensively been characterized regarding surface area, structural changes during derivatization, IMAC, as well as ion exchange and protein-loading capacity and recovery. GNF derivatives revealed high protein-binding capacity (2,000 microg ml(-1) for insulin) and ideal sensitivities, resulting in a detection limit of 50 fmol microl(-1) (for insulin), which is crucial for the detection of low abundant species in biological samples. Compared to other MELDI carrier materials, sensitivity was enhanced on GNF derivatives, which might be ascribed to the fact that GNFs support desorption and ionization mechanisms and by absorbing laser energy in addition to matrix.

Uranium enrichment. Enrichment processes

International Nuclear Information System (INIS)

Alexandre, M.; Quaegebeur, J.P.

2009-01-01

Despite the remarkable progresses made in the diversity and the efficiency of the different uranium enrichment processes, only two industrial processes remain today which satisfy all of enriched uranium needs: the gaseous diffusion and the centrifugation. This article describes both processes and some others still at the demonstration or at the laboratory stage of development: 1 - general considerations; 2 - gaseous diffusion: physical principles, implementation, utilisation in the world; 3 - centrifugation: principles, elementary separation factor, flows inside a centrifuge, modeling of separation efficiencies, mechanical design, types of industrial centrifuges, realisation of cascades, main characteristics of the centrifugation process; 4 - aerodynamic processes: vortex process, nozzle process; 5 - chemical exchange separation processes: Japanese ASAHI process, French CHEMEX process; 6 - laser-based processes: SILVA process, SILMO process; 7 - electromagnetic and ionic processes: mass spectrometer and calutron, ion cyclotron resonance, rotating plasmas; 8 - thermal diffusion; 9 - conclusion. (J.S.)

Optimized enrichment for the detection of Escherichia coli O26 in French raw milk cheeses.

Science.gov (United States)

Savoye, F; Rozand, C; Bouvier, M; Gleizal, A; Thevenot, D

2011-06-01

Our main objective was to optimize the enrichment of Escherichia coli O26 in raw milk cheeses for their subsequent detection with a new automated immunological method. Ten enrichment broths were tested for the detection of E. coli O26. Two categories of experimentally inoculated raw milk cheeses, semi-hard uncooked cheese and 'Camembert' type cheese, were initially used to investigate the relative efficacy of the different enrichments. The enrichments that were considered optimal for the growth of E. coli O26 in these cheeses were then challenged with other types of raw milk cheeses. Buffered peptone water supplemented with cefixim-tellurite and acriflavin was shown to optimize the growth of E. coli O26 artificially inoculated in the cheeses tested. Despite the low inoculum level (1-10 CFU per 25 g) in the cheeses, E. coli O26 counts reached at least 5.10(4) CFU ml(-1) after 24-h incubation at 41.5 °C in this medium. All the experimentally inoculated cheeses were found positive by the immunological method in the enrichment broth selected. Optimized E. coli O26 enrichment and rapid detection constitute the first steps of a complete procedure that could be used in routine to detect E. coli O26 in raw milk cheeses. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

Promotion of uranium enrichment business

International Nuclear Information System (INIS)

Kurushima, Morihiro

1981-01-01

The Committee on Nuclear Power has studied on the basic nuclear power policy, establishing its five subcommittees, entrusted by the Ministry of Nternational Trade and Industry. The results of examination by the subcommittee on uranium enrichment business are given along with a report in this connection by the Committee. In order to establish the nuclear fuel cycle, the aspect of uranium enrichment is essential. The uranium enrichment by centrifugal process has proceeded steadily in Power Reactor and Nuclear Fuel Development Corporation. The following matters are described: the need for domestic uranium enrichment, the outlook for overseas enrichment services and the schedule for establishing domestic enrichment business, the current state of technology development, the position of the prototype enrichment plant, the course to be taken to establish enrichment business the main organization operating the prototype and commercial plants, the system of supplying centrifuges, the domestic conversion of natural uranium the subsidies for uranium enrichment business. (J.P.N.)

Environmental enrichment in the absence of wheel running produces beneficial behavioural and anti-oxidative effects in rats.

Science.gov (United States)

Mármol, F; Sánchez, J; Torres, M N; Chamizo, V D

2017-11-01

The effects of early environmental enrichment (EE) when solving a simple spatial task in adult male rats were assessed. After weaning, rats were housed in pairs in enriched or standard cages (EE and control groups) for two and a half months. Then the rats were trained in a triangular-shaped pool to find a hidden platform whose location was defined in terms of two sources of information, a landmark outside the pool and a particular corner of the pool. As expected, enriched rats reached the platform faster than control animals. Enriched rats also performed better on a subsequent test trial without the platform with the geometry cue individually presented (in the absence of the landmark). Most importantly, the beneficial effects of the present protocol were obtained in the absence of wheel running. Additionally, the antioxidative effects in the hippocampus produced by the previous protocol are also shown. Copyright © 2017 Elsevier B.V. All rights reserved.

From high enriched to low enriched uranium fuel in research reactors

Energy Technology Data Exchange (ETDEWEB)

Van Den Berghe, S.; Leenaers, A.; Koonen, E.; Moons, F.; Sannen, L. [Nuclear Materials Science Institute, SCK.CEN, Boeretang 200, B-2400 Mol (Belgium)

2010-07-01

Since the 1970's, global efforts have been going on to replace the high-enriched (>90% {sup 235}U), low-density UAlx research reactor fuel with high-density, low enriched (<20% {sup 235}U) replacements. This search is driven by the attempt to reduce the civil use of high-enriched material because of proliferation risks and terrorist threats. American initiatives, such as the Global Threat Reduction Initiative (GTRI) and the Reduced Enrichment for Research and Test Reactors (RERTR) program have triggered the development of reliable low-enriched fuel types for these reactors, which can replace the high enriched ones without loss of performance. Most success has presently been obtained with U{sub 3}Si{sub 2} dispersion fuel, which is currently used in many research reactors in the world. However, efforts to search for a replacement with even higher density, which will also allow the conversion of some high flux research reactors that currently cannot change to U{sub 3}Si{sub 2} (eg. BR2 in Belgium), have continued and are for the moment mainly directed towards the U(Mo) alloy fuel (7-10 w% Mo). This paper provides an overview of the past efforts and presents the current status of the U(Mo) development. (authors)

From high enriched to low enriched uranium fuel in research reactors

International Nuclear Information System (INIS)

Van Den Berghe, S.; Leenaers, A.; Koonen, E.; Moons, F.; Sannen, L.

2010-01-01

Since the 1970's, global efforts have been going on to replace the high-enriched (>90% 235 U), low-density UAlx research reactor fuel with high-density, low enriched ( 235 U) replacements. This search is driven by the attempt to reduce the civil use of high-enriched material because of proliferation risks and terrorist threats. American initiatives, such as the Global Threat Reduction Initiative (GTRI) and the Reduced Enrichment for Research and Test Reactors (RERTR) program have triggered the development of reliable low-enriched fuel types for these reactors, which can replace the high enriched ones without loss of performance. Most success has presently been obtained with U 3 Si 2 dispersion fuel, which is currently used in many research reactors in the world. However, efforts to search for a replacement with even higher density, which will also allow the conversion of some high flux research reactors that currently cannot change to U 3 Si 2 (eg. BR2 in Belgium), have continued and are for the moment mainly directed towards the U(Mo) alloy fuel (7-10 w% Mo). This paper provides an overview of the past efforts and presents the current status of the U(Mo) development. (authors)

Uranium enrichment by gas centrifuge

International Nuclear Information System (INIS)

Heriot, I.D.

1988-01-01

After recalling the physical principles and the techniques of centrifuge enrichment the report describes the centrifuge enrichment programmes of the various countries concerned and compares this technology with other enrichment technologies like gaseous diffusion, laser, aerodynamic devices and chemical processes. The centrifuge enrichment process is said to be able to replace with advantage the existing enrichment facilities in the short and medium term. Future prospects of the process are also described, like recycled uranium enrichment and economic improvements; research and development needs to achieve the economic prospects are also indicated. Finally the report takes note of the positive aspect of centrifuge enrichment as far as safeguards and nuclear safety are concerned. 27 figs, 113 refs

Derived enriched uranium market

International Nuclear Information System (INIS)

Rutkowski, E.

1996-01-01

The potential impact on the uranium market of highly enriched uranium from nuclear weapons dismantling in the Russian Federation and the USA is analyzed. Uranium supply, conversion, and enrichment factors are outlined for each country; inventories are also listed. The enrichment component and conversion components are expected to cause little disruption to uranium markets. The uranium component of Russian derived enriched uranium hexafluoride is unresolved; US legislation places constraints on its introduction into the US market

The Independent Medicare Advisory Committee: death panel or smart governing?

Science.gov (United States)

Coleman, Robert

2011-01-01

This comment explores whether health care reform legislation establishes an administrative body effectively charged with the rationing of health care resources; insofar as it establishes a presidentially appointed Independent Medicare Advisory Committee (IMAC). IMAC would be charged with "making two annual reports dictating updated rates for Medicare providers including physicians, hospitals, skilled nursing facilities, home health, and durable medical equipment." IMAC's recommendations would be implemented nationally, subject to a Congressional vote. Congress would be granted a thirty-day window to achieve a simple majority for or against the IMAC recommendations. Part I is an introduction. Part II of this article covers the history of American health care. It lays out the federal government's evolving role in the arena of public health and health care, starting in the mid-nineteenth century and continues up to the present day. Part III examines the existing process by which Medicare spending is controlled. This part focuses on the administrative procedures that control Medicare reimbursements. Part IV examines IMAC. This part discusses IMAC's statutory provisions and the administrative transparency laws IMAC would be bound to follow. The close of this part, draws on three analogies as a gauge for how IMAC will operate: Senator Tom Daschle's Federal Health Board (FHB) proposal; the administrative oversight of the Federal Reserve; and the United Kingdom's National Institute for Health and Clinical Excellence (NICE). Part V creates a snapshot of the U.S. health care system as it operates today. This part emphasizes cost, quality, and accessibility of health care, with comparisons to international and state-run health care systems. Throughout this article there are a number of words, phrases, and agencies that have been given acronyms. For convenience, an index of these acronyms is provided in an appendix following the article.

Evaluation of the impact of density gradient centrifugation on fetal cell loss during enrichment from maternal peripheral blood.

Science.gov (United States)

Emad, Ahmed; Drouin, Régen

2014-09-01

Physical separation by density gradient centrifugation (DGC) is usually used as an initial step of multistep enrichment protocols for purification of fetal cells (FCs) from maternal blood. Many protocols were designed but no single approach was efficient enough to provide noninvasive prenatal diagnosis. Procedures and methods were difficult to compare because of the nonuniformity of protocols among different groups. Recovery of FCs is jeopardized by their loss during the process of enrichment. Any loss of FCs must be minimized because of the multiplicative effect of each step of the enrichment process. The main objective of this study was to evaluate FC loss caused by DGC. Fetal cells were quantified in peripheral blood samples obtained from both euploid and aneuploid pregnancies before and after enrichment by buoyant DGC using Histopaque 1.119 g/mL. Density gradient centrifugation results in major loss of 60% to 80% of rare FCs, which may further complicate subsequent enrichment procedures. Eliminating aggressive manipulations can significantly minimize FC loss. Data obtained raise questions about the appropriateness of the DGC step for the enrichment of rare FCs and argues for the use of the alternative nonaggressive version of the procedure presented here or prioritizing other methods of enrichments. © 2014 John Wiley & Sons, Ltd.

Radiometric enrichment of nonradioactive ores

International Nuclear Information System (INIS)

Mokrousov, V.A.; Lileev, V.A.

1979-01-01

Considered are the methods of mineral enrichment based on the use of the radioation of various types. The physical essence of enrichment processes is presented, their classification is given. Described are the ore properties influencing the efficiency of radiometric enrichment, methods of the properties study and estimation of ore enrichment. New possibilities opened by radiometric enrichment in the technology of primary processing of mineral raw materials are elucidated. A considerable attention is paid to the main and auxiliary equipment for radiometric enrichment. The foundations of the safety engineering are presented in a brief form. Presented are also results of investigations and practical works in the field of enrichment of ores of non-ferrous, ferrous and non-metallic minerals with the help of radiometric methods

PWR fuel of high enrichment with erbia and enriched gadolinia

International Nuclear Information System (INIS)

Bejmer, Klaes-Håkan; Malm, Christian

2011-01-01

Today standard PWR fuel is licensed for operation up to 65-70 MWd/kgU, which in most cases corresponds to an enrichment of more than 5 w/o "2"3"5U. Due to criticality safety reason of storage and transportation, only fuel up to 5 w/o "2"3"5U enrichment is so far used. New fuel storage installations and transportation casks are necessary investments before the reactivity level of the fresh fuel can be significantly increased. These investments and corresponding licensing work takes time, and in the meantime a solution that requires burnable poisons in all pellets of the fresh high-enriched fuel might be used. By using very small amounts of burnable absorber in every pellet the initial reactivity can be reduced to today's levels. This study presents core calculations with fuel assemblies enriched to almost 6 w/o "2"3"5U mixed with a small amount of erbia. Some of the assemblies also contain gadolinia. The results are compared to a reference case containing assemblies with 4.95 w/o "2"3"5U without erbia, utilizing only gadolinia as burnable poison. The comparison shows that the number of fresh fuel assemblies can be reduced by 21% (which increases the batch burnup by 24%) by utilizing the erbia fuel concept. However, increased cost of uranium due to higher enrichment is not fully compensated for by the cost gain due to the reduction of the number assemblies. Hence, the fuel cycle cost becomes slightly higher for the high enrichment erbia case than for the reference case. (author)

77 FR 14838 - General Electric-Hitachi Global Laser Enrichment LLC, Commercial Laser-Based Uranium Enrichment...

Science.gov (United States)

2012-03-13

... Laser Enrichment LLC, Commercial Laser-Based Uranium Enrichment Facility, Wilmington, North Carolina... a license to General Electric-Hitachi Global Laser Enrichment LLC (GLE or the applicant) to authorize construction of a laser-based uranium enrichment facility and possession and use of byproduct...

Simultaneous enrichment of cysteine-containing peptides and phosphopeptides using a cysteine-specific phosphonate adaptable tag (CysPAT) in combination with titanium dioxide (TiO2) chromatography

DEFF Research Database (Denmark)

Huang, Honggang; Pedersen, Martin Haar; Ibañez-Vea, Maria

2016-01-01

to selectively label cysteine-containing peptides (Cys peptides) followed by their enrichment with titanium dioxide (TiO2) and subsequent mass spectrometric analysis. The CysPAT strategy was developed using a synthetic peptide, a standard protein and subsequently the strategy was applied to protein lysates from...

Bacterial Community Profiling of H2/CO2 or Formate-Utilizing Acetogens Enriched from Diverse Ecosystems

Science.gov (United States)

Han, R.; Zhang, L.; Fu, B.; Liu, H.

2014-12-01

Synthetic gases are usually generated from either cellulosic agricultural waste combustion or industrial release and could be subsequently transformed into acetate, ethanol, and/or butyrate by homoacetogenic bacteria, which commonly possess reductive acetyl-CoA synthesis pathway. Homoacetogen-based syngas fermentation technology provides an alternative solution to link greenhouse gas emission control and cellulosic solid waste treatment with biofuels production. The objective of our current project is to hunt for homoacetogens with capabilities of highly efficiently converting syngases to chemical solvents. In this study, we evaluated homoacetogens population dynamics during enrichments and pinpointed dominant homoacetogens representing diverse ecosystems enriched by different substrates. We enriched homoacetogens from four different samples including waste activate sludge, freshwater sediment, anaerobic methanogenic sludge, and cow manure using H2/CO2 (4:1) or formate as substrate for homoacetogen enrichment. Along with the formyltetrahydrofolate synthetase (FTHFS) gene (fhs gene)-specific real time qPCR assay and Terminal Restriction Fragment Length Polymorphism (T-RFLP) analysis, 16S rRNA based 454 high-throughput pyrosequencing was applied to reveal the population dynamic and community structure during enrichment from different origins. Enrichment of homoacetogenic populations coincided with accumulations of short chain fatty acids such as acetate and butyrate. 454 high-throughput pyrosequencing revealed Firmicutes and Spirochaetes populations became dominant while the overall microbial diversity decreased after enrichment. The most abundant sequences among the four origins belonged to the following phyla: Firmicutes, Spirochaetes, Proteobacteria, and Bacteroidetes, accounting for 62.1%-99.1% of the total reads. The major putative homoacetogenic species enriched on H2/CO2 or formate belonged to Clostridium spp., Acetobacterium spp., Acetoanaerobium spp

Contributory role of the tongue and mandible in modulating the in-mouth air cavity at rest.

Science.gov (United States)

Bourdiol, Pierre; Mishellany-Dutour, Anne; Peyron, Marie-Agnes; Woda, Alain

2013-12-01

The tongue-to-palate distance influences the volume of the in-mouth air cavity (IMAC), thus conditioning the entry of aromatic compounds to the olfactory mucosa site. This study was set out to record the IMAC volume by measuring tongue-to-palate distance at rest. Twelve young adults in good general health were tested--lips contacting, with at-rest posture of the tongue and jaw during a silent reading task. Observations in this study were limited to pre- and post-swallowing sequences. The tongue-to-palate distance was measured using three electromagnetic sensors placed on the tongue upper surface. IMAC volume was evaluated from a geometrical model, taking into account the tongue-to-palate distance, the IMAC transversal distance measured from dental casts and historic data giving the anterior-posterior distance of the oral cavity. (1) In the at-rest posture, the tongue-to-palate distance was significantly greater at the posterior sensor level. (2) A vertical shift in tongue posture at rest frequently appeared following deglutition. The upward shifts were of larger amplitude and more frequent than the downward shifts. (3) Evaluation of the IMAC volume gave an approximate value of 12 ml at rest. (4) The chin sensor at rest was 2.8 ± 0.8 mm below its position when in occlusion. The tongue and mandible contribute to shaping the IMAC volume. These and other results suggest that deglutition changes tongue-to-palate distance and influences aroma release during mastication/deglutition acts through modulation of the IMAC volume.

The origin of secondary heavy rare earth element enrichment in carbonatites: Constraints from the evolution of the Huanglongpu district, China

Science.gov (United States)

Smith, M.; Kynicky, J.; Xu, Cheng; Song, Wenlei; Spratt, J.; Jeffries, T.; Brtnicky, M.; Kopriva, A.; Cangelosi, D.

2018-05-01

The silico‑carbonatite dykes of the Huanglongpu area, Lesser Qinling, China, are unusual in that they are quartz-bearing, Mo-mineralised and enriched in the heavy rare earth elements (HREE) relative to typical carbonatites. The textures of REE minerals indicate crystallisation of monazite-(Ce), bastnäsite-(Ce), parisite-(Ce) and aeschynite-(Ce) as magmatic phases. Burbankite was also potentially an early crystallising phase. Monazite-(Ce) was subsequently altered to produce a second generation of apatite, which was in turn replaced and overgrown by britholite-(Ce), accompanied by the formation of allanite-(Ce). Bastnäsite and parisite where replaced by synchysite-(Ce) and röntgenite-(Ce). Aeschynite-(Ce) was altered to uranopyrochlore and then pyrochlore with uraninite inclusions. The mineralogical evolution reflects the evolution from magmatic carbonatite, to more silica-rich conditions during early hydrothermal processes, to fully hydrothermal conditions accompanied by the formation of sulphate minerals. Each alteration stage resulted in the preferential leaching of the LREE and enrichment in the HREE. Mass balance considerations indicate hydrothermal fluids must have contributed HREE to the mineralisation. The evolution of the fluorcarbonate mineral assemblage requires an increase in aCa2+ and aCO32- in the metasomatic fluid (where a is activity), and breakdown of HREE-enriched calcite may have been the HREE source. Leaching in the presence of strong, LREE-selective ligands (Cl-) may account for the depletion in late stage minerals in the LREE, but cannot account for subsequent preferential HREE addition. Fluid inclusion data indicate the presence of sulphate-rich brines during alteration, and hence sulphate complexation may have been important for preferential HREE transport. Alongside HREE-enriched magmatic sources, and enrichment during magmatic processes, late stage alteration with non-LREE-selective ligands may be critical in forming HREE-enriched

Turkey's regulatory plans for high enriched to low enriched conversion of TR-2 reactor core

International Nuclear Information System (INIS)

Guelol Oezdere, Oya

2003-01-01

Turkey is a developing country and has three nuclear facilities two of which are research reactors and one pilot fuel production plant. One of the two research reactors is TR-2 which is located in Cekmece site in Istanbul. TR-2 Reactor's core is composed of both high enriched and low enriched fuel and from high enriched to low enriched core conversion project will take place in year 2005. This paper presents the plans for drafting regulations on the safety analysis report updates for high enriched to low enriched core conversion of TR-2 reactor, the present regulatory structure of Turkey and licensing activities of nuclear facilities. (author)

High enrichment to low enrichment core's conversion. Technical securities

International Nuclear Information System (INIS)

Abbate, P.; Madariaga, M.R.

1990-01-01

This work presents the fulfillment of the technical securities subscribed by INVAP S.E. for the conversion of a high enriched uranium core. The reactor (of 5 thermal Mw), built in the 50's and 60's, is of the 'swimming pool' type, with light water and fuel elements of the curve plates MTR type, enriched at 93.15 %. These are neutronic and thermohydraulic securities. (Author) [es

Beta activity of enriched uranium

International Nuclear Information System (INIS)

Nambiar, P.P.V.J.; Ramachandran, V.

1975-01-01

Use of enriched uranium as reactor fuel necessitates its handling in various forms. For purposes of planning and organising radiation protection measures in enriched uranium handling facilities, it is necessary to have a basic knowledge of the radiation status of enriched uranium systems. The theoretical variations in beta activity and energy with U 235 enrichment are presented. Depletion is considered separately. Beta activity build up is also studied for two specific enrichments, in respect of which experimental values for specific alpha activity are available. (author)

Isotope enrichment

International Nuclear Information System (INIS)

Garbuny, M.

1979-01-01

The invention discloses a method for deriving, from a starting material including an element having a plurality of isotopes, derived material enriched in one isotope of the element. The starting material is deposited on a substrate at less than a critical submonatomic surface density, typically less than 10 16 atoms per square centimeter. The deposit is then selectively irradiated by a laser (maser or electronic oscillator) beam with monochromatic coherent radiation resonant with the one isotope causing the material including the one istope to escape from the substrate. The escaping enriched material is then collected. Where the element has two isotopes, one of which is to be collected, the deposit may be irradiated with radiation resonant with the other isotope and the residual material enriched in the one isotope may be evaporated from the substrate and collected

Laser and gas centrifuge enrichment

Energy Technology Data Exchange (ETDEWEB)

Heinonen, Olli [Senior Fellow, Belfer Center for Science and International Affairs, Harvard Kennedy School, Cambridge, Massachusetts (United States)

2014-05-09

Principles of uranium isotope enrichment using various laser and gas centrifuge techniques are briefly discussed. Examples on production of high enriched uranium are given. Concerns regarding the possibility of using low end technologies to produce weapons grade uranium are explained. Based on current assessments commercial enrichment services are able to cover the global needs of enriched uranium in the foreseeable future.

Real-time PCR detection of Listeria monocytogenes in infant formula and lettuce following macrophage-based isolation and enrichment.

Science.gov (United States)

Day, J B; Basavanna, U

2015-01-01

To develop a rapid detection procedure for Listeria monocytogenes in infant formula and lettuce using a macrophage-based enrichment protocol and real-time PCR. A macrophage cell culture system was employed for the isolation and enrichment of L. monocytogenes from infant formula and lettuce for subsequent identification using real-time PCR. Macrophage monolayers were exposed to infant formula and lettuce contaminated with a serial dilution series of L. monocytogenes. As few as approx. 10 CFU ml(-1) or g(-1) of L. monocytogenes were detected in infant formula and lettuce after 16 h postinfection by real-time PCR. Internal positive PCR controls were utilized to eliminate the possibility of false-negative results. Co-inoculation with Listeria innocua did not reduce the L. monocytogenes detection sensitivity. Intracellular L. monocytogenes could also be isolated on Listeria selective media from infected macrophage lysates for subsequent confirmation. The detection method is highly sensitive and specific for L. monocytogenes in infant formula and lettuce and establishes a rapid identification time of 20 and 48 h for presumptive and confirmatory identification, respectively. The method is a promising alternative to many currently used q-PCR detection methods which employ traditional selective media for enrichment of contaminated food samples. Macrophage enrichment of L. monocytogenes eliminates PCR inhibitory food elements and contaminating food microflora which produce cleaner samples that increase the rapidity and sensitivity of detection. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Enrichment technology. Dependable vendor of gas centrifuges; Enrichment Technology. Zuverlaessiger Lieferant von Gaszentrifugen

Energy Technology Data Exchange (ETDEWEB)

Anon.

2011-10-15

Enrichment Technology is an innovative, high-tech company that develops, manufactures and installs gas centrifuges for enriching uranium. In addition, Enrichment Technology designs enrichment plants that use gas centrifuge technology. This technology offers the most efficient and cost-effective method for enriching uranium yet: high-performance, safe technology that dominates the market with a global share of 45 percent. A determining factor in Enrichment Technology's success is its mission: supplying its customers with safe, reliable technology. Production of the centrifuges requires versatile know-how and collaboration between different departments as well as interdisciplinary teams at the various sites. More than 2000 operators at 8 sites in 5 countries contribute their individual knowledge and personal skills in order to produce this exceptional technology. The head office is in Beaconsfield near London and the operational headquarters are in Almelo in the Netherlands. There are other sites in Germany (Juelich und Gronau), Great Britain (Capenhurst) as well as project sites in the USA and France. Capenhurst is where experienced engineers design new enrichment plants and organise their construction. Centrifuge components are manufactured in Almelo and Juelich, while the pipework needed to connect up the centrifuges is produced at the site in Gronau. In Juelich, highly qualified scientists in interdisciplinary teams are continuously researching ways of improving the current centrifuges. Communication between specialists in the fields of chemistry, physics and engineering forms the basis for the company's success and the key to extending this leading position in the global enrichment market. (orig.)

76 FR 11523 - Atomic Safety and Licensing Board; AREVA Enrichment Services, LLC (Eagle Rock Enrichment Facility...

Science.gov (United States)

2011-03-02

... and Licensing Board; AREVA Enrichment Services, LLC (Eagle Rock Enrichment Facility); Notice of... Governmental Entities Regarding Environmental Portion of Enrichment Facility Licensing Proceeding February 24.... White. In this 10 CFR part 70 proceeding regarding the request of applicant AREVA Enrichment Services...

76 FR 34103 - In the Matter of Areva Enrichment Services, LLC (Eagle Rock Enrichment Facility); Notice of...

Science.gov (United States)

2011-06-10

.... 10-899-02-ML-BD01] In the Matter of Areva Enrichment Services, LLC (Eagle Rock Enrichment Facility...'' portion of this proceeding regarding the December 2008 application by AREVA Enrichment Services, LLC (AES... gas centrifuge uranium enrichment facility--denoted as the Eagle Rock Enrichment Facility (EREF)--in...

Enrichment plants. A survey of major new uranium enriching projects

International Nuclear Information System (INIS)

Kovan, D.

1976-01-01

The work enrichment situation is reported. The development of enrichment in the U.S. and in Europe is outlined. A brief description is given of the technology of separation by diffusion and by centrifugation and the advantages and disadvantages of the two processes are compared. Finally the supply and demand situation is briefly considered. (U.K.)

Removal of PCR error products and unincorporated primers by metal-chelate affinity chromatography.

Directory of Open Access Journals (Sweden)

Indhu Kanakaraj

Full Text Available Immobilized Metal Affinity Chromatography (IMAC has been used for decades to purify proteins on the basis of amino acid content, especially surface-exposed histidines and "histidine tags" genetically added to recombinant proteins. We and others have extended the use of IMAC to purification of nucleic acids via interactions with the nucleotide bases, especially purines, of single-stranded RNA and DNA. We also have demonstrated the purification of plasmid DNA from contaminating genomic DNA by IMAC capture of selectively-denatured genomic DNA. Here we describe an efficient method of purifying PCR products by specifically removing error products, excess primers, and unincorporated dNTPs from PCR product mixtures using flow-through metal-chelate affinity adsorption. By flowing a PCR product mixture through a Cu(2+-iminodiacetic acid (IDA agarose spin column, 94-99% of the dNTPs and nearly all the primers can be removed. Many of the error products commonly formed by Taq polymerase also are removed. Sequencing of the IMAC-processed PCR product gave base-calling accuracy comparable to that obtained with a commercial PCR product purification method. The results show that IMAC matrices (specifically Cu(2+-IDA agarose can be used for the purification of PCR products. Due to the generality of the base-specific mechanism of adsorption, IMAC matrices may also be used in the purification of oligonucleotides, cDNA, mRNA and micro RNAs.

Effects of Enrichment and Litter Parity on Reproductive Performance and Behavior in BALB/c and 129/Sv Mice.

Science.gov (United States)

Whitaker, Julia W; Moy, Sheryl S; Pritchett-Corning, Kathleen R; Fletcher, Craig A

2016-01-01

We examined the effect of adding species-appropriate environmental enrichment items to breeding cages of BALB/cAnNCrl and 129S2/SvPasCrl mice. The 3 enrichment conditions were: 1) cotton nesting material; 2) nesting material plus a paper shelter and rolled paper bedding; and 3) an igloo dome with an exercise wheel in addition to the shelter-group enrichments. We measured litter size, litter survival to weaning age, average pup weight at 21 d, and the interlitter interval to evaluate reproductive performance. A random subset of the first- or second-litter offspring from each enrichment condition and strain was assessed in multiple behavioral tests. Enrichment significantly affected anxiety-like behavior and sociability, with the direction of change dependent on strain and sex. Litter parity had greater effects on some reproductive parameters than did the enrichment condition, and this effect was not solely due to a difference between the first compared with subsequent litters. The significant effects of litter parity on the number of pups born and weaned, female pup weight, and interlitter interval were dependent on the enrichment condition in BALB/c but not 129/Sv mice. Offspring from the first or second litter were included in a generational component to investigate whether enrichment effects on reproduction persist in adult offspring after transfer to a different facility for breeding. Natal cage enrichment had no effect on any reproductive parameter in the transferred mice. Overall, additional enrichment beyond nesting material had a beneficial effect on the interlitter interval in BALB/c mice and on the number of pups weaned in 129/Sv mice.

Developments in uranium enrichment

International Nuclear Information System (INIS)

Mohrhauer, H.

1995-01-01

The enrichment services market is still characterized by overcapacities. While consumption worldwide will rise by some 15% to 39,000 t SWU/a over the next ten years, capacities amount to nearly 50,000 t SWU/a. The price for enrichment services probably has reached its all time low. Prices below U.S. $ 100/kg SWU are not likely to cover costs even of the economically most advanced enrichment processes. Urenco has prepared for the difficult enrichment business in the years to come by streamlining and cost cutting measures. The company intends to hold and increase its share of more than 10% in the world market. The uranium enrichment plant of Gronau will be expanded further. Expansion beyond 1000 t is subject to another permit being granted under the Atomic Energy Act, an application for which was filed in December 1994. Centrifuge technology is the superior enrichment technology, i.e., there is still considerable potential for further development. Construction of enrichment plants employing the centrifuge technology in the United States and in France is being pursued in various phases, from feasibility studies to licensing procedures. Before these plants could be implemented, however, considerable problems of organization would have to be solved, and the market would have to change greatly, respectively. The laser process, at the present time, does not seem to be able to develop into a major industrial competitor. (orig.) [de

Uranium enrichment plans

International Nuclear Information System (INIS)

Gagne, R.W.; Thomas, D.C.

1977-01-01

The status of existing uranium enrichment contracts in the US is reviewed and expected natural uranium requirements for existing domestic uranium enrichment contracts are evaluated. Uncertainty in natural uranium requirements associated with requirements-type and fixed-commitment type contracts is discussed along with implementation of variable tails assay

Centrifuge enrichment program

International Nuclear Information System (INIS)

Astley, E.R.

1976-01-01

Exxon Nuclear has been active in privately funded research and development of centrifuge enrichment technology since 1972. In October of 1975, Exxon Nuclear submitted a proposal to design, construct, and operate a 3000-MT SWU/yr centrifuge enrichment plant, under the provisions of the proposed Nuclear Fuel Assurance Act of 1975. The U.S. Energy Research and Development Administration (ERDA) accepted the proposal as a basis for negotiation. It was proposed to build a 1000-MT SWU/yr demonstration increment to be operational in 1982; and after successful operation for about one year, expand the facilities into a 3000-MT SWU/yr plant. As part of the overall centrifuge enrichment plant, a dedicated centrifuge manufacturing plant would be constructed; sized to support the full 3000-MT SWU/yr plant. The selection of the centrifuge process by Exxon Nuclear was based on an extremely thorough evaluation of current and projected enrichment technology; results show that the technology is mature and the process will be cost effective. The substantial savings in energy (about 93%) from utilization of the centrifuge option rather than gaseous diffusion is a compelling argument. As part of this program, Exxon Nuclear has a large hardware R and D program, plus a prototype centrifuge manufacturing capability in Malta, New York. To provide a full-scale machine and limited cascade test capability, Exxon Nuclear is constructing a $4,000,000 Centrifuge Test Facility in Richland, Washington. This facility was to initiate operations in the Fall of 1976. Exxon Nuclear is convinced that the centrifuge enrichment process is the rational selection for emergence of a commercial enrichment industry

Ascophyllum nodosum enriched bread reduces subsequent energy intake with no effect on post-prandial glucose and cholesterol in healthy, overweight males. A pilot study.

Science.gov (United States)

Hall, A C; Fairclough, A C; Mahadevan, K; Paxman, J R

2012-02-01

It is well recognised that the consumption of seaweed isolates (such as alginate) successfully reduce energy intake and modulate glycaemic and cholesterolaemic responses. However, to date, the effect of adding whole seaweed to bread has not been widely investigated. Hence, this study aims to investigate the acceptability of Ascophyllum nodosum enriched bread as part of a meal, and measure its effect on energy intake and nutrient absorption in overweight, healthy males to see if it has a similar impact. Results from the acceptability study, (79 untrained sensory panellists) indicated that it is acceptable to incorporate seaweed (A. nodosum) into a staple food such as bread at concentrations of up to 4% per 400 g wholemeal loaf. A single blind cross over trial (n=12 males, aged 40.1±12.5 years; BMI 30.8±4.4 kg/m(2)) was used to compare energy intake and nutrient uptake after a breakfast meal using the enriched bread (4% A. nodosum) against the control bread (0% A. nodosum). Consumption of the enriched bread at breakfast led to a significant reduction (16.4%) in energy intake at a test meal 4 h later. Differences between treatment arms for area under the curve, peak values, and time of peak for blood glucose and cholesterol were not significant. Further investigation of potential mechanisms of action is warranted. Copyright © 2011 Elsevier Ltd. All rights reserved.

A Systematic Approach to Marital Enrichment.

Science.gov (United States)

Dinkmeyer, Don; Carlson, Jon

1986-01-01

Presents a systematic approach to enriching marital relationships. The history and current status of marital enrichment is reviewed. An Adlerian approach to marital enrichment is described. Applications of the program in enrichment groups, marriage therapy and couple groups are included. (Author)

77 FR 13367 - General Electric-Hitachi Global Laser Enrichment, LLC, Proposed Laser-Based Uranium Enrichment...

Science.gov (United States)

2012-03-06

... NUCLEAR REGULATORY COMMISSION [NRC-2009-0157] General Electric-Hitachi Global Laser Enrichment, LLC, Proposed Laser-Based Uranium Enrichment Facility, Wilmington, NC AGENCY: Nuclear Regulatory... Impact Statement (EIS) for the proposed General Electric- Hitachi Global Laser Enrichment, LLC (GLE...

The enrichment secondary market

International Nuclear Information System (INIS)

Einbund, D.R.

1986-01-01

This paper will addresses two topics: the background to the present status of the enrichment secondary market and the future outlook of the secondary market in enrichment services, and the viability of the nuclear fuel brokerage industry. These two topics are inevitably connected, as most secondary market activity, not only in enrichment but also in natural uranium, has traditionally been conducted with the participation of brokers. Therefore, the author interrelates these topics

Thermal breeder fuel enrichment zoning

International Nuclear Information System (INIS)

Capossela, H.J.; Dwyer, J.R.; Luce, R.G.; McCoy, D.F.; Merriman, F.C.

1992-01-01

A method and apparatus for improving the performance of a thermal breeder reactor having regions of higher than average moderator concentration are disclosed. The fuel modules of the reactor core contain at least two different types of fuel elements, a high enrichment fuel element and a low enrichment fuel element. The two types of fuel elements are arranged in the fuel module with the low enrichment fuel elements located between the high moderator regions and the high enrichment fuel elements. Preferably, shim rods made of a fertile material are provided in selective regions for controlling the reactivity of the reactor by movement of the shim rods into and out of the reactor core. The moderation of neutrons adjacent the high enrichment fuel elements is preferably minimized as by reducing the spacing of the high enrichment fuel elements and/or using a moderator having a reduced moderating effect. 1 figure

Uranium enrichment in the United States

International Nuclear Information System (INIS)

Hill, J.H.; Parks, J.W.

1975-01-01

History, improvement programs, status of electrical power availability, demands for uranium enrichment, operating plan for the U. S. enriching facilities, working inventory of enriched uranium, possible factors affecting deviations in the operating plan, status of gaseous diffusion technology, status of U. S. gas centrifuge advances, transfer of enrichment technology, gaseous diffusion--gas centrifuge comparison, new enrichment capacity, U. S. separative work pricing, and investment in nuclear energy are discussed. (LK)

Enrichment into the 21st century

International Nuclear Information System (INIS)

Rutkowski, E.

1995-01-01

This article discusses the future of the enrichment services market into the next century. It is estimated that demand for enrichment services will reach 31 million SWU by the end of the century and remain constant for the following 10 years. The current world enrichment capacity is 44 million SWU, or some 50% ahead of the demand. This oversupply is projected to continue into the next century, but in spite of this, several suppliers are planning new enrichment facilities. HEU as a source of enriched uranium is examined. Overall, long-term prices for enrichment services are expected to decline in the coming decade

The commercial role for centrifuge enrichment

International Nuclear Information System (INIS)

Readle, P.H.; Wilcox, P.

1987-01-01

The enrichment market is extremely competitive and capacity greatly exceeds demand. BNFL [British Nuclear Fuels Ltd.] is in a unique position in having commercial experience of the two enrichment technologies currently used industrially: diffusion, and centrifuge enrichment through its associate company Urenco. In addition, BNFL is developing laser enrichment techniques as part of a UK development programme. The paper describes the enrichment market, briefly discusses the relative merits of the various methods of uranium enrichment and concludes that the gas centrifuge will be best able to respond to market needs for at least the remainder of the century. (author)

High enrichment to low enrichment core's conversion. Accidents analysis

International Nuclear Information System (INIS)

Abbate, P.; Rubio, R.; Doval, A.; Lovotti, O.

1990-01-01

This work analyzes the different accidents that may occur in the reactor's facility after the 20% high-enriched uranium core's conversion. The reactor (of 5 thermal Mw), built in the 50's and 60's, is of the 'swimming pool' type, with light water and fuel elements of the curve plates MTR type, enriched at 93.15 %. This analysis includes: a) accidents by reactivity insertion; b) accidents by coolant loss; c) analysis by flow loss and d) fission products release. (Author) [es

Advanced Neutron Source enrichment study

International Nuclear Information System (INIS)

Bari, R.A.; Ludewig, H.; Weeks, J.R.

1996-01-01

A study has been performed of the impact on performance of using low-enriched uranium (20% 235 U) or medium-enriched uranium (35% 235 U) as an alternative fuel for the Advanced Neutron Source, which was initially designed to use uranium enriched to 93% 235 U. Higher fuel densities and larger volume cores were evaluated at the lower enrichments in terms of impact on neutron flux, safety, safeguards, technical feasibility, and cost. The feasibility of fabricating uranium silicide fuel at increasing material density was specifically addressed by a panel of international experts on research reactor fuels. The most viable alternative designs for the reactor at lower enrichments were identified and discussed. Several sensitivity analyses were performed to gain an understanding of the performance of the reactor at parametric values of power, fuel density, core volume, and enrichment that were interpolations between the boundary values imposed on the study or extrapolations from known technology

Prospects and problems of uranium enrichment

International Nuclear Information System (INIS)

Imai, Ryukichi

1974-01-01

The problem of uranium enrichment now concerns principally peaceful nuclear power generation. With the current oil crisis, energy resources assume unprecedented importance. However, the requirements for enriched uranium vary with the vicissitude of the world situation in nuclear power generation; the enterprise of uranium enrichment is related to economic aspect. The following matters are described: dimension of enrichment problem, political factors, changes in requirements, projects in each country, and strategy of enrichment in Japan. (Mori, K.)

Uranium enrichment: an overview

International Nuclear Information System (INIS)

Cazalet, J.

1995-01-01

This paper is a general presentation of uranium enrichment processes and assessments of the prevailing commercial and industrial situations. It gives first some theoretical aspects of enrichment in general and explains the differences between statistical and selective processes in particular. Then a review of the different processes is made with a comparison between them. Finally, some general remarks concerning applications are given and the risks of proliferation related to enrichment are mentioned. (J.S.). 4 refs., 5 figs., 8 tabs

Supply of low enriched (LEU) and highly enriched uranium (HEU) for research reactors

International Nuclear Information System (INIS)

Mueller, H.

1997-01-01

Enriched uranium for research reactors in the form of LEU /= low enriched uranium at 19.75% U-235) and HEU (= highly enriched uranium at 90 to 93% U-235) was and is - due to its high U-235 enrichment - a political fuel other than enriched uranium for power reactors. The sufficient availability of LEU and HEU is a vital question for research reactors, especially in Europe, in order to perform their peaceful research reactor programs. In the past the USA were in the Western hemisphere sole supplier of LEU and HEU. Today the USA have de facto stopped the supply of LEU and HEU, for HEU mainly due to political reasons. This paper deals, among others, with the present availability of LEU and HEU for European research reactors and touches the following topics: - historical US supplies, - influence of the RERTR-program, - characteristics of LEU and HEU, - military HEU enters the civil market, -what is the supply situation for LEU and HEU today? - outlook for safe supplies of LEU and HEU. (author)

77 FR 35366 - Proposed Subsequent Arrangement

Science.gov (United States)

2012-06-13

... arrangement concerns the retransfer of 6,672,212 g of U.S.-origin enriched uranium fuel fabrications scrap, containing 233,977 g of the isotope U-235 (less than five percent enrichment), from Nuclear Fuel Industries... material, which is currently located at Nuclear Fuels Industries, Ltd. in Japan, will be transferred to...

The competitive enrichment market

International Nuclear Information System (INIS)

Parks, J.W.; Huffman, F.C.

1984-01-01

With the enactment of the ''Private Ownership of Special Nuclear Materials Act'' in 1964, the U.S. Government made provisions to enter into the uranium enrichment services business. Since nuclear power was in its infancy and the Government was promoting its growth as well as trying to help U.S. industry sell reactors overseas, the initial contracts (Requirements Contracts) for enrichment services placed most of the risks associated with the supplying of the services on the Government. Projections of nuclear power additions continued to grow and in 1972 the Atomic Energy Commission (AEC) stopped contracting under Requirements Contracts in order to study which mode of contracting best suited the commercial development of the industry. In mid-1973, the AEC introduced the Long-Term Fixed Commitment (LTFC) contract which shifted the risk to the customer. By mid-1974, AEC had contracts which completely used the enrichment capacity of its complex and refused to accept requests for additional contracts. This action further convinced European nations that they should continue to develop their own enrichment capacity and resulted in the EURODIF and URENCO projects. Before this time the U.S. supplied 100% of the world market for enriching services

Enrichment: Dealing with overcapacity

International Nuclear Information System (INIS)

Peterson, C.H.

1989-01-01

Today's surplus of enrichment capacity will continue until at least the end of this century. This will challenge the ingenuity of the separative work unit (SWU) suppliers as they attempt to keep market share and remain profitable in a very competitive marketplace. The utilities will be faced with attractive choices, but making the best choice will require careful analysis and increased attention to market factors. Current demand projections will probably prove too high to the extent that more reactors are canceled or delayed. The DOE has the vast majority of the unused capacity, so it will feel the most immediate impact of this large surplus in productive capacity. The DOE has responded to these market challenges by planning another reorganization of its enriching operations. Without a major agreement among the governments affected by the current surplus in enrichment capacity, the future will see lower prices, more competitive terms, and the gradual substitution of centrifuge or laser enrichment for the gaseous diffusion plants. The competition that is forcing the gaseous diffusion prices down to marginal cost will provide the long-term price basis for the enrichment industry

Development of on-line uranium enrichment monitor of gaseous UF6 for uranium enrichment plant

International Nuclear Information System (INIS)

Lu Xuesheng; Liu Guorong; Jin Huimin; Zhao Yonggang; Li Jinghuai; Hao Xueyuan; Ying Bin; Yu Zhaofei

2013-01-01

An on-line enrichment monitor was developed to measure the enrichment of UF 6 , flowing through the processing pipes in uranium enrichment plant. A Nal (Tl) detector was used to measure the count rates of the 185.7 keV γ-ray emitted from 235 U, and the total quantity of uranium was determined from thermodynamic characteristics of gaseous uranium hexafluoride. The results show that the maximum relative standard deviation is less than 1% when the measurement time is 120 s or more and the pressure is more than 2 kPa in the measurement chamber. Uranium enrichment of gaseous uranium hexafluoride in the output end of cascade can be monitored continuously by using the device. It should be effective for nuclear materials accountability verifications and materials balance verification at uranium enrichment plant. (authors)

Oxygen enrichment incineration

International Nuclear Information System (INIS)

Kim, Jeong Guk; Yang, Hee Chul; Park, Geun Il; Kim, Joon Hyung

2000-10-01

Oxygen enriched combustion technology has recently been used in waste incineration. To apply the oxygen enrichment on alpha-bearing waste incineration, which is being developed, a state-of-an-art review has been performed. The use of oxygen or oxygen-enriched air instead of air in incineration would result in increase of combustion efficiency and capacity, and reduction of off-gas product. Especially, the off-gas could be reduced below a quarter, which might reduce off-gas treatment facilities, and also increase an efficiency of off-gas treatment. However, the use of oxygen might also lead to local overheating and high nitrogen oxides (NOx) formation. To overcome these problems, an application of low NOx oxy-fuel burner and recycling of a part of off-gas to combustion chamber have been suggested

Oxygen enrichment incineration

Energy Technology Data Exchange (ETDEWEB)

Kim, Jeong Guk; Yang, Hee Chul; Park, Geun Il; Kim, Joon Hyung

2000-10-01

Oxygen enriched combustion technology has recently been used in waste incineration. To apply the oxygen enrichment on alpha-bearing waste incineration, which is being developed, a state-of-an-art review has been performed. The use of oxygen or oxygen-enriched air instead of air in incineration would result in increase of combustion efficiency and capacity, and reduction of off-gas product. Especially, the off-gas could be reduced below a quarter, which might reduce off-gas treatment facilities, and also increase an efficiency of off-gas treatment. However, the use of oxygen might also lead to local overheating and high nitrogen oxides (NOx) formation. To overcome these problems, an application of low NOx oxy-fuel burner and recycling of a part of off-gas to combustion chamber have been suggested.

75 FR 10525 - In the Matter of: AREVA Enrichment Services, LLC (Eagle Rock Enrichment Facility) and All Other...

Science.gov (United States)

2010-03-08

...: AREVA Enrichment Services, LLC (Eagle Rock Enrichment Facility) and All Other Persons Who Seek or Obtain... for the Implementation of a Safeguards Information Program (Effective Immediately) I AREVA Enrichment... it to construct and operate a uranium enrichment facility in Bonneville County, Idaho. AES submitted...

Impact of the use of low or medium enriched uranium on the masses of space nuclear reactor power systems

International Nuclear Information System (INIS)

1994-12-01

The design process for determining the mass increase for the substitution of low-enriched uranium (LEU) for high-enriched uranium (HEU) in space nuclear reactor systems is an optimization process which must simultaneously consider several variables. This process becomes more complex whenever the reactor core operates on an in-core thermionic power conversion, in which the fissioning of the nuclear fuel is used to directly heat thermionic emitters, with the subsequent elimination of external power conversion equipment. The increased complexity of the optimization process for this type of system is reflected in the work reported herein, where considerably more information has been developed for the moderated in-core thermionic reactors

76 FR 387 - Atomic Safety and Licensing Board; AREVA Enrichment Services, LLC (Eagle Rock Enrichment Facility)

Science.gov (United States)

2011-01-04

... and Licensing Board; AREVA Enrichment Services, LLC (Eagle Rock Enrichment Facility) December 17, 2010... construction and operation of a gas centrifuge uranium enrichment facility--denoted as the Eagle Rock... site at http://www.nrc.gov/materials/fuel-cycle-fac/arevanc.html . These and other documents relating...

Two-Stage Enzymatic Preparation of Eicosapentaenoic Acid (EPA) And Docosahexaenoic Acid (DHA) Enriched Fish Oil Triacylglycerols.

Science.gov (United States)

Zhang, Zhen; Liu, Fang; Ma, Xiang; Huang, Huihua; Wang, Yong

2018-01-10

Fish oil products in the form of triacylglycerols generally have relatively low contents of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and so it is of potential research and industrial interest to enrich the related contents in commercial products. Thereby an economical and efficient two-stage preparation of EPA and DHA enriched fish oil triacylglycerols is proposed in this study. The first stage was the partial hydrolysis of fish oil by only 0.2 wt.‰ AY "Amano" 400SD which led to increases of EPA and DHA contents in acylglycerols from 19.30 and 13.09 wt % to 25.95 and 22.06 wt %, respectively. Subsequently, products of the first stage were subjected to transesterification with EPA and DHA enriched fatty acid ethyl esters (EDEE) as the second stage to afford EPA and DHA enriched fish oil triacylglycerols by using as low as 2 wt % Novozyme 435. EDEEs prepared from fish oil ethyl ester, and recycled DHA and EPA, respectively, were applied in this stage. Final products prepared with two different sources of EDEEs were composed of 97.62 and 95.92 wt % of triacylglycerols, respectively, with EPA and DHA contents of 28.20 and 21.41 wt % for the former and 25.61 and 17.40 wt % for the latter. Results not only demonstrate this two-stage process's capability and industrial value for enriching EPA and DHA in fish oil products, but also offer new opportunities for the development of fortified fish oil products.

Detection of Listeria monocytogenes from selective enrichment broth using MALDI-TOF Mass Spectrometry.

Science.gov (United States)

Jadhav, Snehal; Sevior, Danielle; Bhave, Mrinal; Palombo, Enzo A

2014-01-31

Conventional methods used for primary detection of Listeria monocytogenes from foods and subsequent confirmation of presumptive positive samples involve prolonged incubation and biochemical testing which generally require four to five days to obtain a result. In the current study, a simple and rapid proteomics-based MALDI-TOF MS approach was developed to detect L. monocytogenes directly from selective enrichment broths. Milk samples spiked with single species and multiple species cultures were incubated in a selective enrichment broth for 24h, followed by an additional 6h secondary enrichment. As few as 1 colony-forming unit (cfu) of L. monocytogenes per mL of initial selective broth culture could be detected within 30h. On applying the same approach to solid foods previously implicated in listeriosis, namely chicken pâté, cantaloupe and Camembert cheese, detection was achieved within the same time interval at inoculation levels of 10cfu/mL. Unlike the routine application of MALDI-TOF MS for identification of bacteria from solid media, this study proposes a cost-effective and time-saving detection scheme for direct identification of L. monocytogenes from broth cultures.This article is part of a Special Issue entitled: Trends in Microbial Proteomics. Globally, foodborne diseases are major causes of illness and fatalities in humans. Hence, there is a continual need for reliable and rapid means for pathogen detection from food samples. Recent applications of MALDI-TOF MS for diagnostic microbiology focused on detection of microbes from clinical specimens. However, the current study has emphasized its use as a tool for detecting the major foodborne pathogen, Listeria monocytogenes, directly from selective enrichment broths. This proof-of-concept study proposes a detection scheme that is more rapid and simple compared to conventional methods of Listeria detection. Very low levels of the pathogen could be identified from different food samples post-enrichment in

The low-enrichment fuel development program

International Nuclear Information System (INIS)

Stahl, D.

1993-01-01

In the 1950s and 1960s, low-power research reactors were built around the world utilized MTR-type fuel elements containing 20% enriched uranium. However, the demand for higher specific power created a need for greater uranium-235 concentrations. Early difficulties in increasing uranium content led to the substitution of highly enriched uranium in place of the 20% enriched fuel previously utilized. The highly enriched material also yielded other benefits including longer core residence time, higher specific reactivity, and somewhat lower cost. Highly enriched material then became readily available and was used for high-power reactors as well as in low-power reactors where 20% enriched material would have sufficed. The trend toward higher and higher specific power also led to the development of the dispersion-type fuels which utilized highly enriched uranium at a concentration of about 40 wt%. In the 1970's, however, concerns were raised about the proliferation resistance of fuels and fuel cycles. As a consequence, the U.S. Department of State has recently prohibited the foreign shipment of highly enriched material, except where prior contractual obligation or special merit exists. This will impact on the availability and utilization of highly enriched uranium for research and test reactor fuel. It has also stimulated development programs on fuels with higher uranium content which would allow the use of uranium of lower enrichment. The purpose of this report is to briefly describe the overall fuel-development program which is coordinated by Argonne National Laboratory for the Department of Energy, and to indicate the current and potential uranium loadings. Other reports will address the individual fuel-development activities in greater detail

Enrichment and desalting of tryptic protein digests and the protein depletion using boron nitride

Energy Technology Data Exchange (ETDEWEB)

Fischnaller, Martin; Köck, Rainer; Bakry, Rania, E-mail: rania.bakry@uibk.ac.at; Bonn, Günther K.

2014-05-01

Highlights: • Protein tryptic digests were desalted and enriched utilizing hexagonal boron nitride. • Phosphopeptides were desalted with high recovery rates. • Boron nitride exhibits high wettability allowing fast sample preparation. • Boron nitride shows protein depletion capability applied for peptide purification. - Abstract: Sample preparation still remains a great challenge in modern bioanalysis and the interest in new efficient solid phase extraction (SPE) materials still remains high. In this work, hexagonal boron nitride (h-BN) is introduced as a new SPE material for the isolation and enrichment of peptides. The h-BN is isoelectronic and structurally similar to graphite. It has remarkable properties including good thermal conductivity, excellent thermal and chemical stability and a better oxidation resistance than graphite. BN attracts increasing interest because of its wide range of applicability. In the present work, the great potential of h-BN, as a new SPE-material, on the enrichment, preconcentration and desalting of tryptic digest of model proteins is demonstrated. A special attention was dedicated to the efficient enrichment of hydrophilic phosphopeptides. Two elution protocols were developed for the enrichment of peptides compatible for subsequent MALDI-MS and ESI-MS analysis. In addition, the recoveries of 5 peptides and 3 phosphopeptides with wide range of pI values utilizing h-BN materials with different surface areas were investigated. 84–106% recovery rate could be achieved using h-BN materials. The results were compared with those obtained using graphite and silica C18 under the same elution conditions, and lower recoveries were obtained. In addition, h-BN was found to have a capability of protein depletion, which is requisite for the peptide profiling.

Enrichment and desalting of tryptic protein digests and the protein depletion using boron nitride

International Nuclear Information System (INIS)

Fischnaller, Martin; Köck, Rainer; Bakry, Rania; Bonn, Günther K.

2014-01-01

Highlights: • Protein tryptic digests were desalted and enriched utilizing hexagonal boron nitride. • Phosphopeptides were desalted with high recovery rates. • Boron nitride exhibits high wettability allowing fast sample preparation. • Boron nitride shows protein depletion capability applied for peptide purification. - Abstract: Sample preparation still remains a great challenge in modern bioanalysis and the interest in new efficient solid phase extraction (SPE) materials still remains high. In this work, hexagonal boron nitride (h-BN) is introduced as a new SPE material for the isolation and enrichment of peptides. The h-BN is isoelectronic and structurally similar to graphite. It has remarkable properties including good thermal conductivity, excellent thermal and chemical stability and a better oxidation resistance than graphite. BN attracts increasing interest because of its wide range of applicability. In the present work, the great potential of h-BN, as a new SPE-material, on the enrichment, preconcentration and desalting of tryptic digest of model proteins is demonstrated. A special attention was dedicated to the efficient enrichment of hydrophilic phosphopeptides. Two elution protocols were developed for the enrichment of peptides compatible for subsequent MALDI-MS and ESI-MS analysis. In addition, the recoveries of 5 peptides and 3 phosphopeptides with wide range of pI values utilizing h-BN materials with different surface areas were investigated. 84–106% recovery rate could be achieved using h-BN materials. The results were compared with those obtained using graphite and silica C18 under the same elution conditions, and lower recoveries were obtained. In addition, h-BN was found to have a capability of protein depletion, which is requisite for the peptide profiling

BlueBerry Isolate, Pterostilbene, Functions as a Potential Anticancer Stem Cell Agent in Suppressing Irradiation-Mediated Enrichment of Hepatoma Stem Cells

Directory of Open Access Journals (Sweden)

Chi-Ming Lee

2013-01-01

Full Text Available For many malignancies, radiation therapy remains the second option only to surgery in terms of its curative potential. However, radiation-induced tumor cell death is limited by a number of factors, including the adverse response of the tumor microenvironment to the treatment and either intrinsic or acquired mechanisms of evasive resistance, and the existence of cancer stem cells (CSCs. In this study, we demonstrated that using different doses of irradiation led to the enrichment of CD133+ Mahlavu cells using flow cytometric method. Subsequently, CD133+ Mahlavu cells enriched by irradiation were characterized for their stemness gene expression, self-renewal, migration/invasion abilities, and radiation resistance. Having established irradiation-enriched CD133+ Mahlavu cells with CSC properties, we evaluated a phytochemical, pterostilbene (PT, found abundantly in blueberries, against irradiation-enriched CSCs. It was shown that PT treatment dose-dependently reduced the enrichment of CD133+ Mahlavu cells upon irradiation; PT treatment also prevented tumor sphere formation, reduced stemness gene expression, and suppressed invasion and migration abilities as well as increasing apoptosis of CD133+ Mahlavu CSCs. Based on our experimental data, pterostilbene could be used to prevent the enrichment of CD133+ hepatoma CSCs and should be considered for future clinical testing as a combined agent for HCC patients.

AEC determines uranium enrichment policy

International Nuclear Information System (INIS)

Anon.

1992-01-01

The Advisory Committee on Uranium Enrichment of the Atomic Energy Commission (AEC) has submitted a report to AEC chairman concerning the promotion of the introduction of advanced material, high performance centrifuges to replace conventional metallic drum centrifuges, and the development of next generation advanced centrifuges. The report also called for the postponement until around 1997 of the decision whether the development should be continued or not on atomic vapor laser isotope separation (AVLIS) and molecular laser isotope separation (MLIS) processes, as well as the virtual freezing of the construction of a chemical process demonstration plant. The report was approved by the AEC chairman in August. The uranium enrichment service market in the world will continue to be characterized by oversupply. The domestic situation of uranium enrichment supply-demand trend, progress of the expansion of Rokkasho enrichment plant, the trend in the development of gas centrifuge process and the basic philosophy of commercializing domestic uranium enrichment are reported. (K.I.)

Gaseous diffusion -- the enrichment workhorse

International Nuclear Information System (INIS)

Shoemaker, J.E. Jr.

1984-01-01

Construction of the first large-scale gaseous diffusion facility was started as part of the Manhattan Project in Oak Ridge, Tennessee, in 1943. This facility, code named ''K-25,'' began operation in January 1945 and was fully on stream by September 1945. Four additional process buildings were later added in Oak Ridge as the demand for enriched uranium escalated. New gaseous diffusion plants were constructed at Paducah, Kentucky, and Portsmouth, Ohio, during this period. The three gaseous diffusion plants were the ''workhorses'' which provided the entire enriched uranium demand for the United States during the 1950s and 1960s. As the demand for enriched uranium for military purposes decreased during the early 1960s, power to the diffusion plants was curtailed to reduce production. During the 1960s, as plans for the nuclear power industry were formulated, the role of the diffusion plants gradually changed from providing highly-enriched uranium for the military to providing low-enriched uranium for power reactors

ToNER: A tool for identifying nucleotide enrichment signals in feature-enriched RNA-seq data.

Directory of Open Access Journals (Sweden)

Yuttachon Promworn

Full Text Available Biochemical methods are available for enriching 5' ends of RNAs in prokaryotes, which are employed in the differential RNA-seq (dRNA-seq and the more recent Cappable-seq protocols. Computational methods are needed to locate RNA 5' ends from these data by statistical analysis of the enrichment. Although statistical-based analysis methods have been developed for dRNA-seq, they may not be suitable for Cappable-seq data. The more efficient enrichment method employed in Cappable-seq compared with dRNA-seq could affect data distribution and thus algorithm performance.We present Transformation of Nucleotide Enrichment Ratios (ToNER, a tool for statistical modeling of enrichment from RNA-seq data obtained from enriched and unenriched libraries. The tool calculates nucleotide enrichment scores and determines the global transformation for fitting to the normal distribution using the Box-Cox procedure. From the transformed distribution, sites of significant enrichment are identified. To increase power of detection, meta-analysis across experimental replicates is offered. We tested the tool on Cappable-seq and dRNA-seq data for identifying Escherichia coli transcript 5' ends and compared the results with those from the TSSAR tool, which is designed for analyzing dRNA-seq data. When combining results across Cappable-seq replicates, ToNER detects more known transcript 5' ends than TSSAR. In general, the transcript 5' ends detected by ToNER but not TSSAR occur in regions which cannot be locally modeled by TSSAR.ToNER uses a simple yet robust statistical modeling approach, which can be used for detecting RNA 5'ends from Cappable-seq data, in particular when combining information from experimental replicates. The ToNER tool could potentially be applied for analyzing other RNA-seq datasets in which enrichment for other structural features of RNA is employed. The program is freely available for download at ToNER webpage (http://www4a

ToNER: A tool for identifying nucleotide enrichment signals in feature-enriched RNA-seq data.

Science.gov (United States)

Promworn, Yuttachon; Kaewprommal, Pavita; Shaw, Philip J; Intarapanich, Apichart; Tongsima, Sissades; Piriyapongsa, Jittima

2017-01-01

Biochemical methods are available for enriching 5' ends of RNAs in prokaryotes, which are employed in the differential RNA-seq (dRNA-seq) and the more recent Cappable-seq protocols. Computational methods are needed to locate RNA 5' ends from these data by statistical analysis of the enrichment. Although statistical-based analysis methods have been developed for dRNA-seq, they may not be suitable for Cappable-seq data. The more efficient enrichment method employed in Cappable-seq compared with dRNA-seq could affect data distribution and thus algorithm performance. We present Transformation of Nucleotide Enrichment Ratios (ToNER), a tool for statistical modeling of enrichment from RNA-seq data obtained from enriched and unenriched libraries. The tool calculates nucleotide enrichment scores and determines the global transformation for fitting to the normal distribution using the Box-Cox procedure. From the transformed distribution, sites of significant enrichment are identified. To increase power of detection, meta-analysis across experimental replicates is offered. We tested the tool on Cappable-seq and dRNA-seq data for identifying Escherichia coli transcript 5' ends and compared the results with those from the TSSAR tool, which is designed for analyzing dRNA-seq data. When combining results across Cappable-seq replicates, ToNER detects more known transcript 5' ends than TSSAR. In general, the transcript 5' ends detected by ToNER but not TSSAR occur in regions which cannot be locally modeled by TSSAR. ToNER uses a simple yet robust statistical modeling approach, which can be used for detecting RNA 5'ends from Cappable-seq data, in particular when combining information from experimental replicates. The ToNER tool could potentially be applied for analyzing other RNA-seq datasets in which enrichment for other structural features of RNA is employed. The program is freely available for download at ToNER webpage (http://www4a.biotec.or.th/GI/tools/toner) and Git

Considering the post-1995 enrichment market

International Nuclear Information System (INIS)

Gunter, L.

1994-01-01

World demand for uranium enrichment services is likely to grow only a little over the next decade, from the current 28 million separative work units (SWU) per year to 33 MSWU per year. Much of the growth will come from Asia where nuclear generating capacity is still increasing. The current situation of the primary enrichment companies is summarized. The primary Western suppliers, Cogema, United States Enrichment Corporation and Urenco, are competing for increased market share in the USA, Europe and Asia as utilities purchase their post-1995 requirements. Entry of the Russian enrichment company, Tenex, into Western markets has been limited by trade restrictions. As a consequence of disarmament, blended weapons material has resulted in a surplus of low-enriched uranium. Together with over-capacity amongst the primary enrichers this has led to an expectation that reduced prices will be negotiable in the medium term. (3 figures). (UK)

Present state of development of uranium enrichment

International Nuclear Information System (INIS)

1979-01-01

The pilot plant for uranium enrichment started the operation on September 12, 1979. The pilot plant has been constructed by the Power Reactor and Nuclear Fuel Development Corp. in Ningyo Pass, Okayama Prefecture. 7000 centrifugal separators will be installed by mid 1981, and yearly production of 70 t SWU is expected. The Uranium Enrichment Committee of Japan Atomic Industrial Forum has made the proposal on the method of forwarding the development of uranium enrichment in Japan to Atomic Energy Commission and related government offices in December, 1978. This survey summarized the trends of uranium enrichment in Japan and foreign countries and the problems about nuclear non-proliferation, and provides with the reference materials. The demand and supply of uranium enrichment in the world, the present states and plans in USA, Europe, USSR and others, the demand and supply of uranium enrichment and the measures for securing it in Japan, the present state and future plan of uranium enrichment project in Japan, the international regulation of uranium enrichment, the recent policy of USA and INFCE, and the trend of the regulation of utilizing enriched uranium are described. Moreover, the concept of separation works in uranium enrichment and the various technologies of separation are explained. (Kako, I.)

Noble gas enrichment studies at JET

International Nuclear Information System (INIS)

Groth, M.; Andrew, P.; Fundamenski, W.; Guo, H.Y.; Hillis, D.L.; Hogan, J.T.; Horton, L.D.; Matthews, G.F.; Meigs, A.G.; Morgan, P.M.; Stamp, M.F.; Hellermann, M. von

2001-01-01

Adequate helium exhaust has been achieved in reactor-relevant ELMy H-mode plasmas in JET performed in the MKII AP and MKII GB divertor geometry. The divertor-characteristic quantities of noble gas compression and enrichment have been experimentally inferred from Charge Exchange Recombination Spectroscopy measurements in the core plasma, and from spectroscopic analysis of a Penning gauge discharge in the exhaust gas. The retention of helium was found to be satisfactory for a next-step device, with enrichment factors exceeding 0.1. The helium enrichment decreases with increasing core plasma density, while the neon enrichment has the opposite behaviour. Analytic and numerical analyses of these plasmas using the divertor impurity code package DIVIMP/NIMBUS support the explanation that the enrichment of noble gases depends significantly on the penetration depth of the impurity neutrals with respect to the fuel atoms. Changes of the divertor plasma configuration and divertor geometry have no effect on the enrichment

Power-Controlled MAC Protocols with Dynamic Neighbor Prediction for Ad hoc Networks

Institute of Scientific and Technical Information of China (English)

LI Meng; ZHANG Lin; XIAO Yong-kang; SHAN Xiu-ming

2004-01-01

Energy and bandwidth are the scarce resources in ad hoc networks because most of the mobile nodes are battery-supplied and share the exclusive wireless medium. Integrating the power control into MAC protocol is a promising technique to fully exploit these precious resources of ad hoc wireless networks. In this paper, a new intelligent power-controlled Medium Access Control (MAC) (iMAC) protocol with dynamic neighbor prediction is proposed. Through the elaborate design of the distributed transmit-receive strategy of mobile nodes, iMAC greatly outperforms the prevailing IEEE 802.11 MAC protocols in not only energy conservation but also network throughput. Using the Dynamic Neighbor Prediction (DNP), iMAC performs well in mobile scenes. To the best of our knowledge, iMAC is the first protocol that considers the performance deterioration of power-controlled MAC protocols in mobile scenes and then proposes a solution. Simulation results indicate that DNP is important and necessary for power-controlled MAC protocols in mobile ad hoc networks.

Extraosseus enrichments in bone scintigraphy

International Nuclear Information System (INIS)

Jochens, R.; Schumacher, T.; Amthauer, H.; Wolter, M.; Stock, W.; Stroszczynski, C.; Moersler, J.P.; Eichstaedt, H.

1996-01-01

Extraosseus enrichments are common findings in bone scintigraphy. Main causes are artifacts by skin or cloth contamination, paravenous and subcutaneous injection. Physical examination, removal of cloths, skin cleaning or further images in differing projections lead to the correct diagnosis artefact or extraosseous enrichments. Further on, extraosseous enrichments are seen in physiological variants. In different diseases extraosseous enrichments are common, especially in urinary tract, liver and extremities. Further diagnostics, e.g. conventional radiologic procedures, sonography and CT scans, have to be performed. In individual cases side results in bone scintigraphy lead to formerly unknown diagnosis, further diagnostic procedure is influenced decisively. Own cases show for example a cerebral apoplectic insult, formerly unknown liver metastasis or metastasis in extraosseous Ewings's sarcoma. (orig.) [de

Report of the Subcommittee on Domestic Uranium Enrichment

International Nuclear Information System (INIS)

1981-01-01

A report by the Subcommittee on Domestic Uranium Enrichment to the Atomic Energy Commission is described; which covers the procedure of the domestic uranium enrichment by centrifugal process up to the commercial production, reviewing the current situation in this field. Domestic uranium enrichment is important in the aspects of securing stable enrichment service, establishing sound fuel cycle, and others. As the future target, the production around the year 2000 is set at 3,000 tons SWU per year at least. The business of uranium enrichment, which is now developed in the Power Reactor and Nuclear Fuel Development Corporation, is to be carried out by private enterprise. The contents are as follows: demand and supply balance of uranium enrichment service, significance of domestic uranium enrichment, evaluation of centrifugal uranium enrichment technology, the target of domestic uranium enrichment, the policy of domestic uranium enrichment promotion. (J.P.N.)

31 CFR 540.316 - Uranium enrichment.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Uranium enrichment. 540.316 Section 540.316 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF... REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of...

Length bias correction in gene ontology enrichment analysis using logistic regression.

Science.gov (United States)

Mi, Gu; Di, Yanming; Emerson, Sarah; Cumbie, Jason S; Chang, Jeff H

2012-01-01

When assessing differential gene expression from RNA sequencing data, commonly used statistical tests tend to have greater power to detect differential expression of genes encoding longer transcripts. This phenomenon, called "length bias", will influence subsequent analyses such as Gene Ontology enrichment analysis. In the presence of length bias, Gene Ontology categories that include longer genes are more likely to be identified as enriched. These categories, however, are not necessarily biologically more relevant. We show that one can effectively adjust for length bias in Gene Ontology analysis by including transcript length as a covariate in a logistic regression model. The logistic regression model makes the statistical issue underlying length bias more transparent: transcript length becomes a confounding factor when it correlates with both the Gene Ontology membership and the significance of the differential expression test. The inclusion of the transcript length as a covariate allows one to investigate the direct correlation between the Gene Ontology membership and the significance of testing differential expression, conditional on the transcript length. We present both real and simulated data examples to show that the logistic regression approach is simple, effective, and flexible.

The reduced enrichment program for JRR-4

International Nuclear Information System (INIS)

Takayanagi, M.

1992-01-01

Japan Research Reactor No. 4(JRR-4) with the rated power of 3.5 MW, swimming pool type research reactor, 93 % enriched uranium ETR-type fuel used, light water moderated and cooled. The first criticality reached on 28th January, 1965. The reactor has operated for about 26 years. However, it was planed to the reduced enrichment of the fuels to low enrichment according to the International Reduced Enrichment for Research and Test Reactors (RERTR) program. This paper describes the program for conversion of the enrichment of fuel from 93 % to less than 20 %. (author)

Competing for the non-US enrichment markets

International Nuclear Information System (INIS)

Anon.

1980-01-01

The article discusses three basic steps: first, the historical perspectives; second, where the enrichment industry and the non-US markets for enrichment stand today (the present situation); and third, the likely future developments, which, for practical purposes, are dealt with in two parts: the non-US enrichment markets in the 1980s; and the non-US enrichment markets beyond the 1980s;

Enriched uranium sales: effect on supply industry

International Nuclear Information System (INIS)

Andersen, R.K.

1985-01-01

The subject is covered in sections: introduction (combined effect of low-enriched uranium (LEU) inventory sales and utility services enrichment contract terms); enrichment market overview; enrichment market dynamics; the reaction of the US Department of Energy; elimination of artificial demand; draw down of inventories; purchase and sale of LEU inventories; tails assay option; unfulfilled requirements for U 3 O 8 ; conclusions. (U.K.)

U.S. forms uranium enrichment corporation

International Nuclear Information System (INIS)

Seltzer, R.

1993-01-01

After almost 40 years of operation, the federal government is withdrawing from the uranium enrichment business. On July 1, the Department of Energy turned over to a new government-owned entity--the US Enrichment Corp. (USEC)--both the DOE enrichment plants at Paducah, Ky., and Portsmouth, Ohio, and domestic and international marketing of enriched uranium from them. Pushed by the inability of DOE's enrichment operations to meet foreign competition, Congress established USEC under the National Energy Policy Act of 1992, envisioning the new corporation as the first step to full privatization. With gross revenues of $1.5 billion in fiscal 1992, USEC would rank 275th on the Fortune 500 list of top US companies. USEC will lease from DOE the Paducah and Portsmouth facilities, built in the early 1950s, which use the gaseous diffusion process for uranium enrichment. USEC's stock is held by the US Treasury, to which it will pay annual dividends. Martin Marietta Energy Systems, which has operated Paducah since 1984 and Portsmouth since 1986 for DOE, will continue to operate both plants for USEC. Closing one of the two facilities will be studied, especially in light of a 40% world surplus of capacity over demand. USEC also will consider other nuclear-fuel-related ventures. USEC will produce only low-enriched uranium, not weapons-grade material. Indeed, USEC will implement a contract now being completed under which the US will purchase weapons-grade uranium from dismantled Russian nuclear weapons and convert it into low-enriched uranium for power reactor fuel

Uranium Conversion & Enrichment

Energy Technology Data Exchange (ETDEWEB)

Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-02-06

The isotopes of uranium that are found in nature, and hence in ‘fresh’ Yellowcake’, are not in relative proportions that are suitable for power or weapons applications. The goal of conversion then is to transform the U₃O₈ yellowcake into UF₆. Conversion and enrichment of uranium is usually required to obtain material with enough ²³⁵U to be usable as fuel in a reactor or weapon. The cost, size, and complexity of practical conversion and enrichment facilities aid in nonproliferation by design.

Immobilised metal-ion affinity chromatography purification of histidine-tagged recombinant proteins : a wash step with a low concentration of EDTA

NARCIS (Netherlands)

Westra, DF; Welling, GW; Koedijk, DGAM; Scheffer, AJ; The, TH; Welling-Wester, S

2001-01-01

Immobilised metal-ion affinity chromatography (IMAC) is widely used for the purification of recombinant proteins in which a poly-histidine tag is introduced. However, other proteins may also bind to IMAC columns. We describe the use of a washing buffer with a low concentration of EDTA (0.5 mM) for

Micropropagation and subsequent enrichment of carotenoids, fatty acids and tocopherol contents in Sedum dasyphyllum L

Science.gov (United States)

Park, Han Yong; Saini, Ramesh Kumar; Gopal, Judy; Keum, Young-Soo; Kim, Doo Hwan; Lee, Onew; Sivanesan, Iyyakkannu

2017-10-01

A promising micropropagation protocol has been systematically established and demonstrated for the enhanced production of carotenoids, tocopherol and fatty acids in shoot tissues of Sedum dasyphyllum. Shoot tip explants were grown on Murashige and Skoog (MS) medium. Different concentrations of N6-benzyladenine (BA) or thidiazuron (TDZ) alone or in combination with α-naphthaleneacetic acid (NAA) were tested in order to stimulate multiple shoot production. Ideal shoot induction (100%) and maximized shoot numbers (36.4) were obtained on explants cultured on media incorporated with 2 µM BA and 1 µM NAA combinations. The in vitro-developed shoots rooted best on half-strength MS media incorporated with 2 µM indole 3-butyric acid. Plantlets were effectively acclimatized in the greenhouse with 100% survival rate. The composition and contents of bioactive compounds such as carotenoids, tocopherol and fatty acids in shoot tissues of S. dasyphyllum were investigated using HPLC and GC-MS. The most abundant carotenoid in the shoot tissue was all-E-lutein (40.3-70.5 µg g-1 FW) followed by 9'-Z-neoxanthin (5.3-9.9 µg g-1 FW), all-E-violaxanthin (4.4-8.2 µg g-1 FW), and all-E-β-carotene (1.6-3.6 µg g-1 FW). The α-tocopherol contents of in vitro-raised shoots was 6.5-fold higher than shoots of greenhouse-grown plants. The primary fatty acids found in shoot tissues were α-linolenic acid (32.0-39.3%), linoleic acid (27.4-38.2%), palmitic acid (13.3-15.5%) and stearic acid (5.2-12.2%). In all, summarizing the findings, the micropropagated S. dasyphyllum showed significant enrichment of valuable bioactive carotenoids (92.3 µg g-1 FW), tocopherols (14.6 µg g-1 FW) and α-linolenic acid (39.3%) compared to their greenhouse counterparts. The protocol demonstrated here could be applied for the mass propagation and production of enhanced bioactive compounds from S. dasyphyllum with credibility.

Uranium enrichment. Technology, economics, capacity

International Nuclear Information System (INIS)

Voigt, W.R. Jr.; Saire, D.E.; Gestson, D.K.; Peske, S.E.; Vanstrum, P.R.

1983-01-01

Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R+D efforts on various processes. (author)

Uranium enrichment: technology, economics, capacity

Energy Technology Data Exchange (ETDEWEB)

Voigt, Jr., W. R.; Vanstrum, P. R.; Saire, D. E.; Gestson, D. K.; Peske, S. E.

1982-08-01

Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R and D efforts on various processes.

Uranium enrichment: technology, economics, capacity

International Nuclear Information System (INIS)

Voigt, W.R. Jr.; Vanstrum, P.R.; Saire, D.E.; Gestson, D.K.; Peske, S.E.

1982-01-01

Large-scale enrichment of uranium has now been carried out for 40 years. While the gaseous diffusion process was the original choice of several countries and continues today to provide the major component of the world production of separative work, the last two decades have witnessed the development of a number of alternative processes for enrichment. These processes, which are being studied and deployed around the world, offer a wide range of technical and economic characteristics which will be useful in assuring adequate capacity to meet projected reactor fuel market needs through the rest of this century at competitive prices. With present uncertainties in future enriched uranium needs, it is apparent that flexibility in the deployment and operation of any enrichment process will be one of the prime considerations for the future. More economical production of separative work not only can have a beneficial impact on reactor fuel costs, but also tends to conserve natural uranium resources. This paper reviews the world scene in the enrichment component of the fuel cycle, including existing or planned commercial-scale facilities and announced R and D efforts on various processes

World enrichment requirements to 2005

International Nuclear Information System (INIS)

Anon.

1991-01-01

The primary enrichment suppliers-Eurodif, Techsnabexport, Urenco, and the US DOE - are positioning themselves to take advantage of the post - 1995 market. Overall, unfilled requirements represent about 40 percent of world requirements in the year 2000. The USA will be the primary market, as US utilities' unfilled enrichment requirements account for over 60 percent of the world's total unfilled requirements. The enrichment market is moving toward more global competition, as each supplier tries to maintain its current regional market base and then to capture additional market share in other regions

DOE enrichment plants-safeguards means business

International Nuclear Information System (INIS)

Donnelly, R.

1987-01-01

The Portsmouth Gaseous Diffusion Plant, owned by the US Department of Energy (DOE) and operated by Martin Marietta Energy Systems, Inc., is a full service enrichment plant. Its long enriching cascade can process uranium hexafluoride (UF 6 ) feeds at almost any 235 U level and can produce UF 6 over the complete spectrum from depleted to very highly enriched uranium. The DOE uranium enrichment program is a government-owned enterprise operating as a business. The operating concerns of the DOE uranium enrichment plants and their safeguards programs have evolved together over the past three decades, and that evolution will likely continue. As the risk associated with possession, processing, and shipment of strategic nuclear material increased, the protection and control of it increased; as the value of the product grew with time, better ways were found to measure and conserve it. In each of these areas, safeguards objectives and the business requirements of the plant are complementary, and the progress made in one area has been reflected by progress in the other. The plant's material control and accountability program has become crucial to such business requirements as quantifying the enriched uranium (separative work units) produced in each monthly period and convincing financial auditors that the multibillion dollar enriched uranium assets located at the Portsmouth plant are properly stated

Uranium enrichment

International Nuclear Information System (INIS)

1991-08-01

This paper reports that in 1990 the Department of Energy began a two-year project to illustrate the technical and economic feasibility of a new uranium enrichment technology-the atomic vapor laser isotope separation (AVLIS) process. GAO believes that completing the AVLIS demonstration project will provide valuable information about the technical viability and cost of building an AVLIS plant and will keep future plant construction options open. However, Congress should be aware that DOE still needs to adequately demonstrate AVLIS with full-scale equipment and develop convincing cost projects. Program activities, such as the plant-licensing process, that must be completed before a plant is built, could take many years. Further, an updated and expanded uranium enrichment analysis will be needed before any decision is made about building an AVLIS plant. GAO, which has long supported legislation that would restructure DOE's uranium enrichment program as a government corporation, encourages DOE's goal of transferring AVLIS to the corporation. This could reduce the government's financial risk and help ensure that the decision to build an AVLIS plant is based on commercial concerns. DOE, however, has no alternative plans should the government corporation not be formed. Further, by curtailing a planned public access program, which would have given private firms an opportunity to learn about the technology during the demonstration project, DOE may limit its ability to transfer AVLIS to the private sector

Availability of enrichment services

International Nuclear Information System (INIS)

Svenke, E.

1977-01-01

The report summarizes major uncertainties which are likely to influence future demands for uranium isotopic enrichment. Since for the next decade the development of nuclear power will be largely concerned with the increment in demand the timely need for enrichment capacity will be particularly sensitive to assumptions about growth rates. Existing worldwide capacity together with capacities under construction will be sufficient well into the 1980's. However, long decision and construction leadtime, uncertainty as to future demand as well as other factors, specifically high capital need, all of which entail financial risks, create hindrances to a timely development of increment. The adequacy of current technology is well demonstrated in plant operation and new technology is under way. Technology is, however, not freely available on a purely commercial basis. Commercial willingness, which anticipates a limited degree of financial risk, is requesting both long term back-up from the utilities that would parallel their firm decisions on the acquisition of nuclear power units, and a protective government umbrella. This situation depends on the symbiotic relationship that exists between the nuclear power generating organizations, the enrichment undertakings and the governments involved. The report accordingly stresses the need for a more cooperative approach and this, moreover, at the multinational level. There is otherwise a risk that proper resources and financing means will not be allocated to the enrichment sector. Export limitations that request the highest degree of industrial processing of nuclear fuel, i.e. the compulsory enrichment of natural uranium, do not serve the interests of overall industrial efficiency

Analysis of the performance of fuel cells PWR with a single enrichment and radial distribution of enrichments

International Nuclear Information System (INIS)

Vargas, S.; Gonzalez, J. A.; Alonso, G.; Del Valle, E.; Xolocostli M, J. V.

2008-01-01

One of the main challenges in the design of fuel assemblies is the efficient use of uranium achieving burnt homogeneous of the fuel rods as well as the burnt maximum possible of the same ones to the unload. In the case of the assemblies type PWR has been decided actually for fuel assemblies with a single radial enrichment. The present work has like effect to show the because of this decision, reason why a comparison of the neutronic performance of two fuel cells takes place with the same enrichment average but one of them with radial distribution of enrichment and the other with a single enrichment equal to the average. The results shown in the present study of the behavior of the neutron flow as well as the power distribution through of assembly sustain the because of a single radial enrichment. (Author)

Civilian inventories of plutonium and highly enriched uranium

International Nuclear Information System (INIS)

Albright, D.

1987-01-01

In the future, commercial laser isotope enrichment technologies, currently under development, could make it easier for national to produce highly enriched uranium secretly. The head of a US firm that is developing a laser enrichment process predicts that in twenty years, major utilities and small countries will have relatively small, on-site, laser-based uranium enrichment facilities. Although these plants will be designed for the production of low enriched uranium, they could be modified to produce highly enriched uranium, an option that raises the possibility of countries producing highly enriched uranium in small, easily hidden facilities. Against this background, most of this report describes the current and future quantities of plutonium and highly enriched uranium in the world, their forms, the facilities in which they are produced, stored, and used, and the extent to which they are transported. 5 figures, 10 tables

NRC licensing of uranium enrichment plants

International Nuclear Information System (INIS)

Moran, B.W.

1991-01-01

The US Nuclear Regulatory Commission (NRC) is preparing a rule making that establishes the licensing requirements for low-enriched uranium enrichment plants. Although implementation of this rule making is timed to correspond with receipt of a license application for the Louisiana Energy Services centrifuge enrichment plant, the rule making is applicable to all uranium enrichment technologies. If ownership of the US gaseous diffusion plants and/or atomic vapor laser isotope separation is transferred to a private or government corporation, these plants also would be licensable under the new rule making. The Safeguards Studies Department was tasked by the NRC to provide technical assistance in support of the rule making and guidance preparation process. The initial and primary effort of this task involved the characterization of the potential safeguards concerns associated with a commercial enrichment plant, and the licensing issues associated with these concerns. The primary safeguards considerations were identified as detection of the loss of special nuclear material, detection of unauthorized production of material of low strategic significance, and detection of production of uranium enriched to >10% 235 U. The primary safeguards concerns identified were (1) large absolute limit of error associated with the material balance closing, (2) the inability to shutdown some technologies to perform a cleanout inventory of the process system, and (3) the flexibility of some technologies to produce higher enrichments. Unauthorized production scenarios were identified for some technologies that could prevent conventional material control and accounting programs from detecting the production and removal of 5 kg 235 U as highly enriched uranium. Safeguards techniques were identified to mitigate these concerns

Environmental enrichment choices of shelter cats.

Science.gov (United States)

Ellis, J J; Stryhn, H; Spears, J; Cockram, M S

2017-08-01

Choices made by cats between different types of environmental enrichment may help shelters to prioritize how to most effectively enrich cat housing, especially when limited by space or funds. This study investigates the environmental enrichment use of cats in a choice test. Twenty-six shelter cats were kept singularly in choice chambers for 10days. Each chamber had a central area and four centrally-linked compartments containing different types of environmental enrichment: 1) an empty control, 2) a prey-simulating toy, 3) a perching opportunity, and 4) a hiding opportunity. Cat movement between compartments was quantitatively recorded using a data-logger. Enriched compartments were visited significantly more frequently during the light period than during the dark period. Cats spent a significantly greater percentage of time in the hiding compartment (median=55%, IQR=46) than in the toy compartment (median=2%, IQR=9), or in the empty control compartment (median=4%, IQR=4). These results provide additional evidence to support the value of a hiding box to cats housed in a novel environment, in that they choose hiding relative to other types of environmental enrichment. Copyright © 2017 Elsevier B.V. All rights reserved.

Uranium enrichment: heading for a cliff

International Nuclear Information System (INIS)

Norman, C.

1987-01-01

Thanks to drastic cost cutting in the past 2 years, US enrichment plants now have the lowest cost production in the world, but US prices are still higher than those of overseas competitors because the business is paying for past mistakes. The most serious difficulty is that the Department of Energy (DOE), which owns and operates the US enrichment enterprise, is paying more than $500 million a year to the Tennessee Valley Authority (TVA) for electricity it once thought it would need but no longer requires. Another is that billions of dollars were spent in the 1970s and early 1980s to build new capacity that is now not needed. As a result, the enrichment enterprise has accumulated a debt to the US Treasury that the General Accounting Office (GAO) estimates at $8.8 billion. This paper presents the background and current debate in Congress about the difficulties facing the enrichment industry. In the midst of this debate over the future of the enterprise, the development of the next generation of enrichment technology is being placed in jeopardy. Known as atomic vapor laser isotope separation, or AVLIS, the process was viewed as the key to the long-term competitiveness of US enrichment. As the federal deficit mounted, however, funding for the AVLIS program was cut back and the timetable was stretched out. The US enrichment program has reached the point at which Congress will be forced to make some politically difficult decisions

Hf and Nd Isotope Evidence for Production of an Incompatible Trace Element Enriched Crustal Reservoir in Early Earth (Invited)

Science.gov (United States)

Brandon, A. D.; Debaille, V.; Lapen, T. J.

2010-12-01

The final significant stage of accretion of the Earth was likely a collision between proto-Earth and a Mars sized impactor that formed the Moon. This event is thought to have produced enough thermal energy to melt all or most of the Earth, with a consequent magma ocean (MO). During subsequent cooling, the Earth would have formed its protocrust and corresponding mantle lithosphere, consisting of solidified basalt-komatiitic melt, in combination with buoyant cumulates and late stage residual melts from the MO. Relative to the convecting mantle, portions of this protolithosphere are likely to have been enriched in incompatible trace elements (ITE) in sufficient quantities to contain a significant amount of the bulk Earth’s budget for rare earth elements, U, Th, and Hf. If the protolithosphere was negatively buoyant, it may have overturned at or near the final stages of MO crystallization and a significant portion of that material may have been transported into the deep mantle where it resided and remixed into the convecting mantle over Earth history [1,2]. If the protolithosphere remained positively buoyant, its crust would have likely begun to erode from surface processes, and subsequently recycled back into the mantle over time as sediment and altered crust, once a subduction mechanism arose. The Nd and Hf isotopic compositions of Earth’s earliest rocks support the idea that an early-formed ITE-enriched reservoir was produced. The maxima in 142Nd/144Nd for 3.85 to 3.64 Ga rocks from Isua, Greenland decreases from +20 ppm to +12 ppm relative to the present day mantle value, respectively [3]. This indicates mixing of an early-formed ITE enriched reservoir back into the convecting mantle. In addition, zircons from the 3.1 Ga Jack Hills conglomerate indicate that material with an enriched 176Lu/177Hf of ~0.02 and an age of 4.4 Ga or greater was present at the Earth’s surface over the first 2 Ga of Earth history, supporting the scenario of a positively buoyant

Safety of uranium enrichment plant

International Nuclear Information System (INIS)

Yonekawa, Shigeru; Morikami, Yoshio; Morita, Minoru; Takahashi, Tsukasa; Tokuyasu, Takashi.

1991-01-01

With respect to safety evaluation of the gas centrifuge enrichment facility, several characteristic problems are described as follows. Criticality safety in the cascade equipments can be obtained to maintain the enrichment of UF 6 below 5 %. External radiation dose equivalent rate of the 30B cylinder is low enough, the shield is not necessary. Penetration ratio of the two-stage HEPA filters for UF 6 aerosol is estimated at 10 -9 . From the experimental investigation, vacuum tightness is not damaged by destruction of gas centrifuge rotor. Carbon steel can be used for uranium enrichment equipments under the condition below 100degC. (author)

Profile of World Uranium Enrichment Programs - 2007

International Nuclear Information System (INIS)

Laughter, Mark D.

2007-01-01

It is generally agreed that the most difficult step in building a nuclear weapon is acquiring weapons grade fissile material, either plutonium or highly enriched uranium (HEU). Plutonium is produced in a nuclear reactor, while HEU is produced using a uranium enrichment process. Enrichment is also an important step in the civil nuclear fuel cycle, in producing low enriched uranium (LEU) for use in fuel for nuclear reactors. However, the same equipment used to produce LEU for nuclear fuel can also be used to produce HEU for weapons. Safeguards at an enrichment plant are the array of assurances and verification techniques that ensure uranium is only enriched to LEU, no undeclared LEU is produced, and no uranium is enriched to HEU or secretly diverted. There are several techniques for enriching uranium. The two most prevalent are gaseous diffusion, which uses older technology and requires a lot of energy, and gas centrifuge separation, which uses more advanced technology and is more energy efficient. Gaseous diffusion plants (GDPs) provide about 40% of current world enrichment capacity, but are being phased out as newer gas centrifuge enrichment plants (GCEPs) are constructed. Estimates of current and future enrichment capacity are always approximate, due to the constant upgrades, expansions, and shutdowns occurring at enrichment plants, largely determined by economic interests. Currently, the world enrichment capacity is approximately 53 million kg-separative work units (SWU) per year, with 22 million in gaseous diffusion and 31 million in gas centrifuge plants. Another 23 million SWU/year of capacity are under construction or planned for the near future, almost entirely using gas centrifuge separation. Other less-efficient techniques have also been used in the past, including electromagnetic and aerodynamic separations, but these are considered obsolete, at least from a commercial perspective. Laser isotope separation shows promise as a possible enrichment technique

The future cost of uranium enrichment

International Nuclear Information System (INIS)

Pouris, A.

1986-01-01

The cost of uranium enrichment is the most important factor determining the fuel cost of nuclear energy. This paper attempts to forecast the future direction of the price of separative work by examining the forces that determine it. It is argued that the interplay among the characteristics of enrichment technologies, the structure of the international market, and the balance of supply and demand determine the enrichment price. The analysis indicates that all forces point towards a price much lower than the current one. It is predicted that, depending on the technological advances, the price of separative work unit for uranium enrichment will range between $40 and $90 by the year 2000. (author)

31 CFR 540.308 - Low Enriched Uranium (LEU).

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Low Enriched Uranium (LEU). 540.308... OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.308 Low Enriched Uranium (LEU). The term low enriched...

Industrial aspects in uranium enrichment

International Nuclear Information System (INIS)

Mezin, M.

1982-05-01

Characteristics of isotope separation processes in operation and under development are discussed. These include the number of stages in series, the number of components, the component unit capacity and enery requirements. The implementation of an enrichment process and the question of an enrichment plant in Australia are also considered

Advances in uranium enrichment processes

International Nuclear Information System (INIS)

Rae, H.K.; Melvin, J.G.; Slater, J.B.

1986-05-01

Advances in gas centrifuges and development of the atomic vapour laser isotope separation process promise substantial reductions in the cost of enriched uranium. The resulting reduction in LWR fuel costs could seriously erode the economic advantage of CANDU, and in combination with LWR design improvements, shortened construction times and increased operational reliability could allow the LWR to overtake CANDU. CANDU's traditional advantages of neutron economy and high reliability may no longer be sufficient - this is the challenge. The responses include: combining neutron economy and dollar economy by optimizing CANDU for slightly enriched uranium fuel; developing cost-reducing improvements in design, manufacture and construction; and reducing the cost of heavy water. Technology is a renewable resource which must be continually applied to a product for it to remain competitive in the decades to come. Such innovation is a prerequisite to Canada increasing her share of the international market for nuclear power stations. The higher burn-up achievable with enriched fuel in CANDU can reduce the fuel cycle costs by 20 to 40 percent for a likely range of costs for yellowcake and separative work. Alternatively, some of the benefits of a higher fissile content can take the form of a cheaper reactor core containing fewer fuel channels and less heavy water, and needing only a single fuelling machine. An opportunity that is linked to this need to introduce an enriched uranium fuel cycle into CANDU is to build an enrichment business in Canada. This could offer greater value added to our uranium exports, security of supply for enriched CANDUs, technological growth in Canada and new employment opportunities. AECL has a study in progress to define this opportunity

Environmental enrichment for aquatic animals.

Science.gov (United States)

Corcoran, Mike

2015-05-01

Aquatic animals are the most popular pets in the United States based on the number of owned pets. They are popular display animals and are increasingly used in research settings. Enrichment of captive animals is an important element of zoo and laboratory medicine. The importance of enrichment for aquatic animals has been slower in implementation. For a long time, there was debate over whether or not fish were able to experience pain or form long-term memories. As that debate has reduced and the consciousness of more aquatic animals is accepted, the need to discuss enrichment for these animals has increased. Copyright © 2015 Elsevier Inc. All rights reserved.

Changing perspectives on the importance of urban phosphorus inputs as the cause of nutrient enrichment in Lough Neagh.

Science.gov (United States)

Foy, R H; Lennox, S D; Gibson, C E

2003-07-01

The scale and chronology of the phosphorus (P) enrichment of Lough Neagh, a large hypertrophic lake, was assessed using, as enrichment proxies, published palaeocological studies on diatoms and chironomid head capsules preserved in the lake sediments and, from 1974, monitoring data from the lake and its inflowing rivers. Enrichment commenced in 1880, and the scale and chronology of the diatom and chironomid records were similar up to 1960, but in the 1960s, chironomid accumulation rates increased dramatically, whereas diatom rates remained unchanged. From subsequent lake monitoring, the absence of a diatom response after 1960 was attributed to silica limitation so that P could be considered as the driver of increased diatom production only up to 1960. Using a coefficient for the demand for P by diatoms of 4 microg P mg SiO(2)(-1), it was calculated that the increased diatom production between 1881 and 1961 required an increase in lake P of 26 microg P l(-1). This value is close to the predicted increase of 22.5 microg P l(-1) in the lake caused by inputs of P from sewage treatment works and septic tanks. There was no evidence that diffuse source P contributed to enrichment over this period. Enrichment up to 1960 appears modest in comparison to subsequent years. From 1961 to 1974, lake P was estimated to have increased by 62 microg P l(-1), but only 25 microg P l(-1) of this increase was attributable to greater loadings of P from urban and septic tank sources. The enrichment response of chironomids at this time was also much greater than expected from a regression-derived relationship between urban P inputs and chironomid accumulation rates suggesting additional sources of P. The larger than expected increase in lake P was attributed to the onset of a significant internal loading of P and the commencement of an increase in diffuse source loadings of P. River monitoring has shown that diffuse P has increased steadily since 1974, more than counterbalancing a 40

Review of uranium enrichment prospects in Canada, 1976

International Nuclear Information System (INIS)

Developments since 1971 which affect the prospects for uranium enrichment in Canada from the federal government point of view are reviewed. The market for enriched uranium to the year 2000 is similar to that projected in 1971. The committed enrichment capacity of the world will be sufficient until 1990. The Canadian uranium mining capability may be adequate to supply an enrichment plant, but the present reserves policy along with the currently known resources are likely to restrict exports of its products during the plant life. Prices for enriched uranium produced in Canada would be higher than those reported by other proposed new plants; however, newer enrichment techniques have some potential for cost reductions. Application of enrichment with U235 (or plutonium and U233/thorium) to CANDU offers some uranium resource conservation and possible slight power cost reductions. Construction of an enrichment plant in Canada to supply the export market is less attractive in 1976 than in 1971, but there is potential for such a business in the future. (L.L.)

Profile of World Uranium Enrichment Programs-2009

International Nuclear Information System (INIS)

Laughter, Mark D.

2009-01-01

It is generally agreed that the most difficult step in building a nuclear weapon is acquiring fissile material, either plutonium or highly enriched uranium (HEU). Plutonium is produced in a nuclear reactor, whereas HEU is produced using a uranium enrichment process. Enrichment is also an important step in the civil nuclear fuel cycle, in producing low enriched uranium (LEU) for use as fuel for nuclear reactors to generate electricity. However, the same equipment used to produce LEU for nuclear reactor fuel can also be used to produce HEU for weapons. Safeguards at an enrichment plant are the array of assurances and verification techniques that ensure uranium is not diverted or enriched to HEU. There are several techniques for enriching uranium. The two most prevalent are gaseous diffusion, which uses older technology and requires a lot of energy, and gas centrifuge separation, which uses more advanced technology and is more energy efficient. Gaseous diffusion plants (GDPs) provide about 40% of current world enrichment capacity but are being phased out as newer gas centrifuge enrichment plants (GCEPs) are constructed. Estimates of current and future enrichment capacity are always approximate, due to the constant upgrades, expansions, and shutdowns occurring at enrichment plants, largely determined by economic interests. Currently, the world enrichment capacity is approximately 56 million kilogram separative work units (SWU) per year, with 22.5 million in gaseous diffusion and more than 33 million in gas centrifuge plants. Another 34 million SWU/year of capacity is under construction or planned for the near future, almost entirely using gas centrifuge separation. Other less-efficient techniques have also been used in the past, including electromagnetic and aerodynamic separations, but these are considered obsolete, at least from a commercial perspective. Laser isotope separation shows promise as a possible enrichment technique of the future but has yet to be

Evaluating biomarkers for prognostic enrichment of clinical trials.

Science.gov (United States)

Kerr, Kathleen F; Roth, Jeremy; Zhu, Kehao; Thiessen-Philbrook, Heather; Meisner, Allison; Wilson, Francis Perry; Coca, Steven; Parikh, Chirag R

2017-12-01

A potential use of biomarkers is to assist in prognostic enrichment of clinical trials, where only patients at relatively higher risk for an outcome of interest are eligible for the trial. We investigated methods for evaluating biomarkers for prognostic enrichment. We identified five key considerations when considering a biomarker and a screening threshold for prognostic enrichment: (1) clinical trial sample size, (2) calendar time to enroll the trial, (3) total patient screening costs and the total per-patient trial costs, (4) generalizability of trial results, and (5) ethical evaluation of trial eligibility criteria. Items (1)-(3) are amenable to quantitative analysis. We developed the Biomarker Prognostic Enrichment Tool for evaluating biomarkers for prognostic enrichment at varying levels of screening stringency. We demonstrate that both modestly prognostic and strongly prognostic biomarkers can improve trial metrics using Biomarker Prognostic Enrichment Tool. Biomarker Prognostic Enrichment Tool is available as a webtool at http://prognosticenrichment.com and as a package for the R statistical computing platform. In some clinical settings, even biomarkers with modest prognostic performance can be useful for prognostic enrichment. In addition to the quantitative analysis provided by Biomarker Prognostic Enrichment Tool, investigators must consider the generalizability of trial results and evaluate the ethics of trial eligibility criteria.

Immobilized palladium(II) ion affinity chromatography for recovery of recombinant proteins with peptide tags containing histidine and cysteine.

Science.gov (United States)

Kikot, Pamela; Polat, Aise; Achilli, Estefania; Fernandez Lahore, Marcelo; Grasselli, Mariano

2014-11-01

Fusion of peptide-based tags to recombinant proteins is currently one of the most used tools for protein production. Also, immobilized metal ion affinity chromatography (IMAC) has a huge application in protein purification, especially in research labs. The combination of expression systems of recombinant tagged proteins with this robust chromatographic system has become an efficient and rapid tool to produce milligram-range amounts of proteins. IMAC-Ni(II) columns have become the natural partners of 6xHis-tagged proteins. The Ni(II) ion is considered as the best compromise of selectivity and affinity for purification of a recombinant His-tagged protein. The palladium(II) ion is also able to bind to side chains of amino acids and form ternary complexes with iminodiacetic acid and free amino acids and other sulfur-containing molecules. In this work, we evaluated two different cysteine- and histidine-containing six amino acid tags linked to the N-terminal group of green fluorescent protein (GFP) and studied the adsorption and elution conditions using novel eluents. Both cysteine-containing tagged GFPs were able to bind to IMAC-Pd(II) matrices and eluted successfully using a low concentration of thiourea solution. The IMAC-Ni(II) system reaches less than 20% recovery of the cysteine-containing tagged GFP from a crude homogenate of recombinant Escherichia coli, meanwhile the IMAC-Pd(II) yields a recovery of 45% with a purification factor of 13. Copyright © 2014 John Wiley & Sons, Ltd.

Enrichment and proteomic analysis of plasma membrane from rat dorsal root ganglions

Directory of Open Access Journals (Sweden)

Lin Yong

2009-11-01

Full Text Available Abstract Background Dorsal root ganglion (DRG neurons are primary sensory neurons that conduct neuronal impulses related to pain, touch and temperature senses. Plasma membrane (PM of DRG cells plays important roles in their functions. PM proteins are main performers of the functions. However, mainly due to the very low amount of DRG that leads to the difficulties in PM sample collection, few proteomic analyses on the PM have been reported and it is a subject that demands further investigation. Results By using aqueous polymer two-phase partition in combination with high salt and high pH washing, PMs were efficiently enriched, demonstrated by western blot analysis. A total of 954 non-redundant proteins were identified from the plasma membrane-enriched preparation with CapLC-MS/MS analysis subsequent to protein separation by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE or shotgun digestion. 205 (21.5% of the identified proteins were unambiguously assigned as PM proteins, including a large number of signal proteins, receptors, ion channel and transporters. Conclusion The aqueous polymer two-phase partition is a simple, rapid and relatively inexpensive method. It is well suitable for the purification of PMs from small amount of tissues. Therefore, it is reasonable for the DRG PM to be enriched by using aqueous two-phase partition as a preferred method. Proteomic analysis showed that DRG PM was rich in proteins involved in the fundamental biological processes including material exchange, energy transformation and information transmission, etc. These data would help to our further understanding of the fundamental DRG functions.

Enriching Metal-Oxidizing Microbes from Marine Sediment on Cathodic Currents

Science.gov (United States)

Rowe, A. R.; Nealson, K. H.

2013-12-01

terminal electron acceptors. Batch feeds of different electron donors resulted in a spike in electric current over a 24 hour period of time. Two subsequent enrichment cultures have been phylogenetically characterized that were supplied solely with elemental sulfur (So) as an electron donor, and either nitrate, δ-MnO2 or Fe3+ as the terminal electron acceptor. Current efforts are geared towards isolating currently iron-oxidizing and sulfur-oxidizing lithotrophs.

Enrichment of Acinetobacter spp. from food samples.

Science.gov (United States)

Carvalheira, Ana; Ferreira, Vânia; Silva, Joana; Teixeira, Paula

2016-05-01

Relatively little is known about the role of foods in the chain of transmission of acinetobacters and the occurrence of different Acinetobacter spp. in foods. Currently, there is no standard procedure to recover acinetobacters from food in order to gain insight into the food-related ecology and epidemiology of acinetobacters. This study aimed to assess whether enrichment in Dijkshoorn enrichment medium followed by plating in CHROMagar™ Acinetobacter medium is a useful method for the isolation of Acinetobacter spp. from foods. Recovery of six Acinetobacter species from food spiked with these organisms was compared for two selective enrichment media (Baumann's enrichment and Dijkshoorn's enrichment). Significantly (p enrichment. Next, the Dijkshoorn's enrichment followed by direct plating on CHROMagar™ Acinetobacter was applied to detect Acinetobacter spp. in different foods. Fourteen different presumptive acinetobacters were recovered and assumed to represent nine different strains on the basis of REP-PCR typing. Eight of these strains were identified by rpoB gene analysis as belonging to the species Acinetobacter johnsonii, Acinetobacter calcoaceticus, Acinetobacter guillouiae and Acinetobacter gandensis. It was not possible to identify the species level of one strain which may suggests that it represents a distinct species. Copyright © 2015 Elsevier Ltd. All rights reserved.

Enrichment of sub-milligram size carbon samples

NARCIS (Netherlands)

Kitagawa, H; vanderPlicht, J

We have developed a carbon isotope enrichment system for use in conjunction with the Groningen Accelerator Mass Spectrometer. Using thermal diffusion of CO, we obtained an enrichment factor of about 3 for C-13 for half-gram carbon in 5 days. This means we expect for C-14 an enrichment factor of 6,

Review of environmental enrichment for broiler chickens

DEFF Research Database (Denmark)

Riber, Anja Brinch; Van de Weerd, H.A.; de Jong, I.C.

2018-01-01

to improvements of the biological function. This definition has been broadened to include practical and economic aspects, as any enrichment strategy that adversely affects the health of animals or that has too many economic or practical constraints will never be implemented on commercial farms and thus never...... benefit animals. Environmental enrichment for broilers often has the purpose of satisfying behavioral needs and/or stimulating the broilers to an increased level of activity, which among others will reduce the occurrence of leg problems. Potentially successful environmental enrichments for broiler...... chickens are elevated resting-places, panels, barriers, and bales of straw (“point-source enrichment”), as well as covered verandas and outdoor ranges (“complex enriched environments”). Many of the ideas for environmental enrichment for broilers need to be further developed and studied, preferably...

Current perspective of the uranium enrichment market

International Nuclear Information System (INIS)

Laughon, K.O.

1986-01-01

Over the past several years, developments in the uranium enrichment market have required the Department of Energy (DOE) to make a number of changes in the U.S. enrichment enterprise. These changes have been made to allow DOE to conduct our enrichment business so as to be more responsive to changing market forces. Needless to say, some of these changes have been difficult, but they have been necessary if they are to conduct a healthy and competitive uranium enrichment business in the United States. This paper discusses several topics, including: The Uranium Enrichment Market, Utility Services (US) Contracts, Reduced Prices, Incentive Pricing, Better Customer Services, and Advanced Technology. In addition to these topics, information is provided on the recent court action regarding the US Contracts and the viability finding on the uranium mining industry

Review of environmental enrichment for broiler chickens.

Science.gov (United States)

Riber, A B; van de Weerd, H A; de Jong, I C; Steenfeldt, S

2018-02-01

Welfare problems are commonly found in both conventional and organic production of broiler chickens. In order to reduce the extent of welfare problems, it has been suggested to provide stimulating, enriched environments. The aim of the present paper is to provide a review of the effect on behavior and welfare of the different kinds of environmental enrichments in the production of broilers that have been described in the scientific literature. Environmental enrichment is defined as an improvement of the environment of captive animals, which increases the behavioral opportunities of the animal and leads to improvements of the biological function. This definition has been broadened to include practical and economic aspects, as any enrichment strategy that adversely affects the health of animals or that has too many economic or practical constraints will never be implemented on commercial farms and thus never benefit animals. Environmental enrichment for broilers often has the purpose of satisfying behavioral needs and/or stimulating the broilers to an increased level of activity, which among others will reduce the occurrence of leg problems. Potentially successful environmental enrichments for broiler chickens are elevated resting-places, panels, barriers, and bales of straw ("point-source enrichment"), as well as covered verandas and outdoor ranges ("complex enriched environments"). Many of the ideas for environmental enrichment for broilers need to be further developed and studied, preferably in commercial trials, with respect to the use, the effect on behavior and on other welfare aspects such as leg health, and the interaction with genotype, production system, stocking density, light, and flock size. In addition, information on the practical application and the economics of the production system is often lacking, although it is important for application in practice. © 2017 Poultry Science Association Inc.

Super enrichment of Fe-group nuclei in solar flares and their association with large 3He enrichments

International Nuclear Information System (INIS)

Anglin, J.D.; Dietrich, W.F.; Simpson, J.A.

1977-01-01

''Fe''/He ratios at approximately 2 MeV/n have been measured in 60 solar flares and periods of enhanced fluxes during the interval 1972-1976. The observed ditribution of ratios is extremely wide with values ranging from approximately 1 to more than 1000 times the solar abundance ratio. In constrast, most of the CHO/He ratios for the same flares lie within a factor 2 of the observed mean value of 2 x 10 -2 . While experimental limitations prevent a complete correlation study of Fe-group and 3 He abundances, comparison of flares with large Fe enrichments with flares with large 3 He enrichments for the period 1969-1976 shows that a 3 He-rich flare is also likely to be rich in iron. We feel that the association of 3 He and Fe enrichments may be explained by a two-stage process in which a preliminary enrichment of heavy nuclei precedes the preferential acceleration of ambient 3 He. Nuclear interactions are ruled out as the principal source of the enriched 3 He. (author)

A new generation of 99.999% enriched 28Si single crystals for the determination of Avogadro’s constant

Science.gov (United States)

Abrosimov, N. V.; Aref'ev, D. G.; Becker, P.; Bettin, H.; Bulanov, A. D.; Churbanov, M. F.; Filimonov, S. V.; Gavva, V. A.; Godisov, O. N.; Gusev, A. V.; Kotereva, T. V.; Nietzold, D.; Peters, M.; Potapov, A. M.; Pohl, H.-J.; Pramann, A.; Riemann, H.; Scheel, P.-T.; Stosch, R.; Wundrack, S.; Zakel, S.

2017-08-01

A metrological challenge is currently underway to replace the present definition of the kilogram. One prerequisite for this is that the Avogadro constant, N A, which defines the number of atoms in a mole, needs to be determined with a relative uncertainty of better than 2  ×  10-8. The method applied in this case is based on the x-ray crystal density experiment using silicon crystals. The first attempt, in which silicon of natural isotopic composition was used, failed. The solution chosen subsequently was the usage of silicon highly enriched in 28Si from Russia. First, this paper reviews previous efforts from the very first beginnings to an international collaboration with the goal of producing a 28Si single crystal with a mass of 5 kg, an enrichment greater than 0.9999 and of sufficient chemical purity. Then the paper describes the activities of a follow-up project, conducted by PTB, to produce a new generation of highly enriched silicon in order to demonstrate the quasi-industrial and reliable production of more than 12 kg of the 28Si material with enrichments of five nines. The intention of this project is also to show the availability of 28Si single crystals as a guarantee for the future realisation of the redefined kilogram.

Cavitation resistance of 45 and 2H13 steels laser enriched with silicon carbides and hafnium

International Nuclear Information System (INIS)

Skodo, M.; Giren, B.; Cenian, A.

1999-01-01

Cavitation resistance of 45 and H13 steels with surface layers enriched with Hf and SiC compounds was investigated. All contamination elements were spread over the samples surfaces and subsequently alloyed with core material by CO 2 laser beam. Cavitation tests carried out at the rotating disk facility revealed multiple - 5 to 10 times - increase of erosion resistance of the processed materials during the incubation period of the destruction. This effect was found not to be decisively linked to obtained microhardness changes. (author)

Comparative proteomic assessment of matrisome enrichment methodologies

Science.gov (United States)

Krasny, Lukas; Paul, Angela; Wai, Patty; Howard, Beatrice A.; Natrajan, Rachael C.; Huang, Paul H.

2016-01-01

The matrisome is a complex and heterogeneous collection of extracellular matrix (ECM) and ECM-associated proteins that play important roles in tissue development and homeostasis. While several strategies for matrisome enrichment have been developed, it is currently unknown how the performance of these different methodologies compares in the proteomic identification of matrisome components across multiple tissue types. In the present study, we perform a comparative proteomic assessment of two widely used decellularisation protocols and two extraction methods to characterise the matrisome in four murine organs (heart, mammary gland, lung and liver). We undertook a systematic evaluation of the performance of the individual methods on protein yield, matrisome enrichment capability and the ability to isolate core matrisome and matrisome-associated components. Our data find that sodium dodecyl sulphate (SDS) decellularisation leads to the highest matrisome enrichment efficiency, while the extraction protocol that comprises chemical and trypsin digestion of the ECM fraction consistently identifies the highest number of matrisomal proteins across all types of tissue examined. Matrisome enrichment had a clear benefit over non-enriched tissue for the comprehensive identification of matrisomal components in murine liver and heart. Strikingly, we find that all four matrisome enrichment methods led to significant losses in the soluble matrisome-associated proteins across all organs. Our findings highlight the multiple factors (including tissue type, matrisome class of interest and desired enrichment purity) that influence the choice of enrichment methodology, and we anticipate that these data will serve as a useful guide for the design of future proteomic studies of the matrisome. PMID:27589945

Study on the radiotoxicology of enriched uranium

International Nuclear Information System (INIS)

Zhu Shoupeng; Zheng Siying; Wang Guolin; Wang Chongdao; Cao Genfa

1987-12-01

A study on the retentive peculiarity of soluble enriched uranium UO 2 F 2 were observed after iv once or consecutive ip qd x 3d to Wistar male rats. The dynamic retention of radioactivity in the body showed that the enriched uranium UO 2 F 2 was chiefly localized in kidney, and then in skeleton and liver. The radioactivity of the enriched uranium UO 2 F 2 in skeleton rose steadily while the concentratoin in kidney and liver droped. When enriched uranium UO 2 F 2 was accumulated in organism, it caused chromosome aberrations on bone marrow cells. Results indicated that the chromosome aberration rates were elevated when the dose of the enriched uranium UO 2 F 2 was increased, at the same time, the cell division was depressed. Accumulation of insoluble enriched uranium U 3 O 8 in gastrointestinal tract was well described by a two exponential expression. Values of retention estimate for fast component, T 1 = 0.34 d, and for relatively long term component, T 2 = 4.05 d. The deposition of UO 2 F 2 in the intact skin was only 0.16 to 0.18% of the total contaminated UO 2 F 2 . Penetration of the enriched uranium UO 2 F 2 was dominantly increased in abraded skin. This value is about 25 to 32 times as compaired with that in intact skin. Retention of the enriched uranium UO 2 F 2 through abraded skins was dominantly localized in kidney and skeleton

Enrichment technology. Dependable vendor of gas centrifuges

International Nuclear Information System (INIS)

Anon.

2011-01-01

Enrichment Technology is an innovative, high-tech company that develops, manufactures and installs gas centrifuges for enriching uranium. In addition, Enrichment Technology designs enrichment plants that use gas centrifuge technology. This technology offers the most efficient and cost-effective method for enriching uranium yet: high-performance, safe technology that dominates the market with a global share of 45 percent. A determining factor in Enrichment Technology's success is its mission: supplying its customers with safe, reliable technology. Production of the centrifuges requires versatile know-how and collaboration between different departments as well as interdisciplinary teams at the various sites. More than 2000 operators at 8 sites in 5 countries contribute their individual knowledge and personal skills in order to produce this exceptional technology. The head office is in Beaconsfield near London and the operational headquarters are in Almelo in the Netherlands. There are other sites in Germany (Juelich und Gronau), Great Britain (Capenhurst) as well as project sites in the USA and France. Capenhurst is where experienced engineers design new enrichment plants and organise their construction. Centrifuge components are manufactured in Almelo and Juelich, while the pipework needed to connect up the centrifuges is produced at the site in Gronau. In Juelich, highly qualified scientists in interdisciplinary teams are continuously researching ways of improving the current centrifuges. Communication between specialists in the fields of chemistry, physics and engineering forms the basis for the company's success and the key to extending this leading position in the global enrichment market. (orig.)

Comments on applications of reduced enrichment fuels

International Nuclear Information System (INIS)

Winkler, M.H.

1983-01-01

Full text: I will briefly describe the experience gained using different fuels in the SAPHIR reactor in Switzerland. The SAPHIR has been operating since 1957 and was the first swimming pool reactor built outside of the United States, which was originally known as the Geneva Conference Reactor. The first core was loaded with 20 percent enriched high density UO 2 fuel with a density of about 2.5 grams per cc, fabricated in 1955 by Oak Ridge National Laboratory. After a few years of operation at a power level of one MW, more than one batch of the elements released small amounts of fission products mainly Xe and Kr. When these releases were discovered, high enriched fuel was becoming available so that the fuel fabricators began to produce the lower density high enriched fuels. During this transition from fabrication of low to high enriched fuels no one could foresee that the stone age of nuclear fuel fabrication would come back again. Therefore, we did not investigate the reasons for the fission product release from the high density low enriched UO 2 fuel. The second fuel type used in the SAPHIR was the 90 percent enriched low density U 3 O 8 fuel fabricated by NUKEM. This high enriched fuel has performed satisfactorily over the years. Since 1968, the core has been using improved 23 plate fuel elements with a loading of 280 grams of uranium. The reactor power has been recently increased to five MW. An additional increase in the power level to 10 MW is planned at the end of next year so that heavier loaded elements will be needed. In order to follow the recommendations of the INFCE working group 8C and in cooperation with the reduced enrichment program, we intend to initially reduce the fuel enrichment to 45 percent. Last year we ordered five fuel elements with a loading of 320 grams 235 U/element and 45 percent enrichment for full power tests. Unfortunately, the delivery of the necessary enriched fuel uranium has been delayed and it is not available at this time. If

Continuous monitoring of variations in the 235U enrichment of uranium in the header pipework of a centrifuge enrichment plant

International Nuclear Information System (INIS)

Packer, T.W.

1991-01-01

Non-destructive assay equipment, based on gamma-ray spectrometry and x-ray fluorescence analysis has previously been developed for confirming the presence of low enriched uranium in the header pipework of UF 6 gas centrifuge enrichment plants. However inspections can only be carried out occasionally on a limited number of pipes. With the development of centrifuge enrichment technology it has been suggested that more frequent, or ideally, continuous measurements should be made in order to improve safeguards assurance between inspections. For this purpose we have developed non-destructive assay equipment based on continuous gamma-ray spectrometry and x-ray transmission measurements. This equipment is suitable for detecting significant changes in the 235 U enrichment of uranium in the header pipework of new centrifuge enrichment plants. Results are given in this paper of continuous measurements made in the laboratory and also on header pipework of a centrifuge enrichment plant at Capenhurst

Procedures for the retention of gaseous tritium released from a tritium enrichment plant

International Nuclear Information System (INIS)

Gutowski, H.; Bracha, M.

1987-01-01

General aim of the study is the comparison of two alternative processes for the retention of gaseous tritium which is released during normal operation and emergency operation in a tritium-enrichment-plant. Two processes for the retention of tritium were compared: 1. Oxidation-process. The hydrogen-gas containing HT will be burnt on an oxidation catalyst to H 2 O and HTO. In a subsequent step the water will be removed from the process by condensation, freezing and adsorption. 2. TROC-process (Tritium Removal by Organic Compounds). The tritium is added to an organic compound (acid) via catalyst. This reaction is irreversible and leads to solid products. (orig./RB) [de

Enriching an effect calculus with linear types

DEFF Research Database (Denmark)

Egger, Jeff; Møgelberg, Rasmus Ejlers; Simpson, Alex

2009-01-01

We define an ``enriched effect calculus'' by conservatively extending  a type theory for computational effects with primitives from linear logic. By doing so, we obtain a generalisation of linear type theory, intended as a formalism for expressing linear aspects of effects. As a worked example, we...... formulate  linearly-used continuations in the enriched effect calculus. These are captured by a fundamental translation of the enriched effect calculus into itself, which extends existing call-by-value and call-by-name linearly-used CPS translations. We show that our translation is involutive. Full...... completeness results for the various linearly-used CPS translations  follow. Our main results, the conservativity of enriching the effect calculus with linear primitives, and the involution property of the fundamental translation, are proved using a category-theoretic semantics for the enriched effect calculus...

Multinational uranium enrichment in the Middle East

International Nuclear Information System (INIS)

Ahmad, Ali; Salahieh, Sidra; Snyder, Ryan

2017-01-01

The Joint Comprehensive Plan of Action (JCPOA) agreed to by Iran and the P5+1 in July 2015 placed restrictions on Iran’s nuclear program while other Middle Eastern countries– Egypt, Jordan, Saudi Arabia, Turkey, and the United Arab Emirates–are planning to build their own nuclear power plants to meet increasing electricity demands. Although the JCPOA restricts Iran's uranium enrichment program for 10–15 years, Iran's neighbors may choose to develop their own national enrichment programs giving them a potential nuclear weapons capability. This paper argues that converting Iran's national enrichment program to a more proliferation-resistant multinational arrangement could offer significant economic benefits–reduced capital and operational costs–due to economies of scale and the utilization of more efficient enrichment technologies. In addition, the paper examines policy aspects related to financing, governance, and how multinational enrichment could fit into the political and security context of the Middle East. A multinational enrichment facility managed by regional and international partners would provide more assurance that it remains peaceful and could help build confidence between Iran and its neighbors to cooperate in managing other regional security challenges. - Highlights: • Freezing Iran's nuclear program is an opportunity to launch joint initiatives in ME. • A joint uranium enrichment program in the Middle East offers economic benefits. • Other benefits include improved nuclear security and transparency in the region.

Large-scale analysis of in Vivo phosphorylated membrane proteins by immobilized metal ion affinity chromatography and mass spectrometry

DEFF Research Database (Denmark)

Nühse, Thomas S; Stensballe, Allan; Jensen, Ole N

2003-01-01

specificity. We investigated the potential of IMAC in combination with capillary liquid chromatography coupled to tandem mass spectrometry for the identification of plasma membrane phosphoproteins of Arabidopsis. Without chemical modification of peptides, over 75% pure phosphopeptides were isolated from...... plasma membrane digests and detected and sequenced by mass spectrometry. We present a scheme for two-dimensional peptide separation using strong anion exchange chromatography prior to IMAC that both decreases the complexity of IMAC-purified phosphopeptides and yields a far greater coverage...... of monophosphorylated peptides. Among the identified sequences, six originated from different isoforms of the plasma membrane H(+)-ATPase and defined two previously unknown phosphorylation sites at the regulatory C terminus. The potential for large-scale identification of phosphorylation sites on plasma membrane...

Implementation trial of high performance trace analysis/environmental sampling (HPTA/ES) in uranium centrifuge enrichment plants

International Nuclear Information System (INIS)

Nackaerts, H.; Kloeckner, W.; Landresse, G.; MacLean, F.; Betti, M.; Forcina, V.; Hiernaut, T.; Tamborini, G.; Koch, L.; Schenkel, R.

1999-01-01

Field trials have demonstrated that the analysis of particles upon swipes obtained from inside nuclear installations provides clear signatures of past operations in that installation. This can offer a valuable tool for gaining assurance regarding the compliance with declared activities and the absence of undeclared activities (e.g. enrichment, reprocessing, and reactor operation) at such sites. This method, known as 'Environmental Sampling' (ES) or 'High Performance Trace Analysis' (HPTA) in EURATOM terminology, is at present being evaluated by the EURATOM Safeguards Directorate (ESD) in order to assess its possible use in nuclear installations within the European Union. It is expected that incorporation of HPTA/ES of sample collection and analysis into routine inspection activities will allow EURATOM to improve the effectiveness of safeguards in these installations and hopefully save inspection resources as well. The EURATOM Safeguards Directorate has therefore performed implementation trials involving the collection of particles by the so-called swipe sampling method in uranium centrifuge enrichment plants and hot cells in the European Union. These samples were subsequently analysed by the Joint Research Centre, Institute for Transuranium Elements (ITU) in Karlsruhe. Sampling points were chosen on the basis of the activities performed in the vicinity and by considering the possible ways through which particles are released, diffused and transported. The aim was to test the efficiency of the method as regards: the collection of enough representative material; the identification of a large enough number of uranium particles; the accurate measurement of the enrichment of the uranium particles found on the swipe; the representativity of the results in respect of past activities in the plant; the capability of detecting whether highly enriched uranium has been produced, used or occasionally transported in a location where low enriched uranium is routinely produced in

21 CFR 137.260 - Enriched corn meals.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Enriched corn meals. 137.260 Section 137.260 Food... Flours and Related Products § 137.260 Enriched corn meals. (a) Enriched corn meals are the foods, each of which conforms to the definition and standard of identity prescribed for a kind of corn meal by §§ 137...

PC based uranium enrichment analyser

International Nuclear Information System (INIS)

Madan, V.K.; Gopalakrishana, K.R.; Bairi, B.R.

1991-01-01

It is important to measure enrichment of unirradiated nuclear fuel elements during production as a quality control measure. An IBM PC based system has recently been tested for enrichment measurements for Nuclear Fuel Complex (NFC), Hyderabad. As required by NFC, the system has ease of calibration. It is easy to switch the system from measuring enrichment of fuel elements to pellets and also automatically store the data and the results. The system uses an IBM PC plug in card to acquire data. The card incorporates programmable interval timers (8253-5). The counter/timer devices are executed by I/O mapped I/O's. A novel algorithm has been incorporated to make the system more reliable. The application software has been written in BASIC. (author). 9 refs., 1 fig

A Summary of Actinide Enrichment Technologies and Capability Gaps

Energy Technology Data Exchange (ETDEWEB)

Patton, Bradley D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Robinson, Sharon M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-01-01

The evaluation performed in this study indicates that a new program is needed to efficiently provide a national actinide radioisotope enrichment capability to produce milligram-to-gram quantities of unique materials for user communities. This program should leverage past actinide enrichment, the recent advances in stable isotope enrichment, and assessments of the future requirements to cost effectively develop this capability while establishing an experience base for a new generation of researchers in this vital area. Preliminary evaluations indicate that an electromagnetic isotope separation (EMIS) device would have the capability to meet the future needs of the user community for enriched actinides. The EMIS technology could be potentially coupled with other enrichment technologies, such as irradiation, as pre-enrichment and/or post-enrichment systems to increase the throughput, reduce losses of material, and/or reduce operational costs of the base EMIS system. Past actinide enrichment experience and advances in the EMIS technology applied in stable isotope separations should be leveraged with this new evaluation information to assist in the establishment of a domestic actinide radioisotope enrichment capability.

Uranium enrichment (a strategy analysis overview)

International Nuclear Information System (INIS)

Blahnik, C.

1979-08-01

An analysis of available information on enrichment technology, separative work supply and demand, and SWU cost is presented. Estimates of present and future enrichment costs are provided for use in strategy analyses of alternate nuclear fuel cycles and systems. (auth)

Providing incentives to buy US enrichment

International Nuclear Information System (INIS)

Steyn, J.

1985-01-01

The U.S. Department of Energy is making a series of commercial and technological decisions crucial to its future as an enriching enterprise. The state of US enrichment, as revealed in this years AIF Fuel Cycle conference, is reported. (U.K.)

Synthesis of 15N-enriched fertilizers. Pt. II. Synthesis of 15N-enriched urea

International Nuclear Information System (INIS)

Bondassolli, J.A.; Trivelin, P.C.O.; Mortatti, J.; Victoria, R.L.

1988-01-01

The results of studies on the production of 15 N-urea through the reaction between 15 N-enriched anhidrous ammonia, carbon monoxide and sulfur, using hydrogen sulfite as a auto catalizers and methyl alcohol as a liquid reaction medium is presented. The influence of the quantities of reagents on final yield of synthesised urea were studied. Analysis of the cost of 5 Atoms % 15 N-enriched urea were made. (M.A.C.) [pt

Induced-Pluripotent-Stem-Cell-Derived Primitive Macrophages Provide a Platform for Modeling Tissue-Resident Macrophage Differentiation and Function.

Science.gov (United States)

Takata, Kazuyuki; Kozaki, Tatsuya; Lee, Christopher Zhe Wei; Thion, Morgane Sonia; Otsuka, Masayuki; Lim, Shawn; Utami, Kagistia Hana; Fidan, Kerem; Park, Dong Shin; Malleret, Benoit; Chakarov, Svetoslav; See, Peter; Low, Donovan; Low, Gillian; Garcia-Miralles, Marta; Zeng, Ruizhu; Zhang, Jinqiu; Goh, Chi Ching; Gul, Ahmet; Hubert, Sandra; Lee, Bernett; Chen, Jinmiao; Low, Ivy; Shadan, Nurhidaya Binte; Lum, Josephine; Wei, Tay Seok; Mok, Esther; Kawanishi, Shohei; Kitamura, Yoshihisa; Larbi, Anis; Poidinger, Michael; Renia, Laurent; Ng, Lai Guan; Wolf, Yochai; Jung, Steffen; Önder, Tamer; Newell, Evan; Huber, Tara; Ashihara, Eishi; Garel, Sonia; Pouladi, Mahmoud A; Ginhoux, Florent

2017-07-18

Tissue macrophages arise during embryogenesis from yolk-sac (YS) progenitors that give rise to primitive YS macrophages. Until recently, it has been impossible to isolate or derive sufficient numbers of YS-derived macrophages for further study, but data now suggest that induced pluripotent stem cells (iPSCs) can be driven to undergo a process reminiscent of YS-hematopoiesis in vitro. We asked whether iPSC-derived primitive macrophages (iMacs) can terminally differentiate into specialized macrophages with the help of growth factors and organ-specific cues. Co-culturing human or murine iMacs with iPSC-derived neurons promoted differentiation into microglia-like cells in vitro. Furthermore, murine iMacs differentiated in vivo into microglia after injection into the brain and into functional alveolar macrophages after engraftment in the lung. Finally, iPSCs from a patient with familial Mediterranean fever differentiated into iMacs with pro-inflammatory characteristics, mimicking the disease phenotype. Altogether, iMacs constitute a source of tissue-resident macrophage precursors that can be used for biological, pathophysiological, and therapeutic studies. Copyright © 2017 Elsevier Inc. All rights reserved.

Boron isotopic enrichment by displacement chromatography

International Nuclear Information System (INIS)

Mohapatra, K.K.; Bose, Arun

2014-01-01

10 B enriched boron is used in applications requiring high volumetric neutron absorption (absorption cross section- 3837 barn for thermal and 1 barn for 1 MeV fast neutron). It is used in fast breeder reactor (as control rod material), in neutron counter, in Boron Neutron Capture Therapy etc. Owing to very small separation factor, boron isotopic enrichment is a complex process requiring large number of separation stages. Heavy Water Board has ventured in industrial scale production of 10 B enriched boron using Exchange Distillation Process as well as Ion Displacement Chromatography Process. Ion Displacement Chromatography process is used in Boron Enrichment Plant at HWP, Manuguru. It is based on isotopic exchange between borate ions (B(OH) 4 - ) on anion exchange resin and boric acid passing through resin. The isotopic exchange takes place due to difference in zero point energy of 10 B and 11 B

Oxygen enriched combustion system performance study. Phase 2: 100 percent oxygen enriched combustion in regenerative glass melters, Final report

Energy Technology Data Exchange (ETDEWEB)

Tuson, G.B.; Kobayashi, H.; Campbell, M.J.

1994-08-01

The field test project described in this report was conducted to evaluate the energy and environmental performance of 100% oxygen enriched combustion (100% OEC) in regenerative glass melters. Additional objectives were to determine other impacts of 100% OEC on melter operation and glass quality, and to verify on a commercial scale that an on-site Pressure Swing Adsorption oxygen plant can reliably supply oxygen for glass melting with low electrical power consumption. The tests constituted Phase 2 of a cooperative project between the United States Department of Energy, and Praxair, Inc. Phase 1 of the project involved market and technical feasibility assessments of oxygen enriched combustion for a range of high temperature industrial heating applications. An assessment of oxygen supply options for these applications was also performed during Phase 1, which included performance evaluation of a pilot scale 1 ton per day PSA oxygen plant. Two regenerative container glass melters were converted to 100% OEC operation and served as host sites for Phase 2. A 75 ton per day end-fired melter at Carr-Lowrey Glass Company in Baltimore, Maryland, was temporarily converted to 100% OEC in mid- 1990. A 350 tpd cross-fired melter at Gallo Glass Company in Modesto, California was rebuilt for permanent commercial operation with 100% OEC in mid-1991. Initially, both of these melters were supplied with oxygen from liquid storage. Subsequently, in late 1992, a Pressure Swing Adsorption oxygen plant was installed at Gallo to supply oxygen for 100% OEC glass melting. The particular PSA plant design used at Gallo achieves maximum efficiency by cycling the adsorbent beds between pressurized and evacuated states, and is therefore referred to as a Vacuum/Pressure Swing Adsorption (VPSA) plant.

Long term assurance of supply of uranium enrichment

International Nuclear Information System (INIS)

1978-01-01

After elaborating a number of key questions on uranium enrichment, the representatives of 10 countries and of the EC commission present their answers. Attention is paid to the assurance of uranium supply, to uranium enrichment, market trends and flexibility in enrichment agreements

GOMA: functional enrichment analysis tool based on GO modules

Institute of Scientific and Technical Information of China (English)

Qiang Huang; Ling-Yun Wu; Yong Wang; Xiang-Sun Zhang

2013-01-01

Analyzing the function of gene sets is a critical step in interpreting the results of high-throughput experiments in systems biology.A variety of enrichment analysis tools have been developed in recent years,but most output a long list of significantly enriched terms that are often redundant,making it difficult to extract the most meaningful functions.In this paper,we present GOMA,a novel enrichment analysis method based on the new concept of enriched functional Gene Ontology (GO) modules.With this method,we systematically revealed functional GO modules,i.e.,groups of functionally similar GO terms,via an optimization model and then ranked them by enrichment scores.Our new method simplifies enrichment analysis results by reducing redundancy,thereby preventing inconsistent enrichment results among functionally similar terms and providing more biologically meaningful results.

Enrichment of light hydrocarbon mixture

Science.gov (United States)

Yang,; Dali, [Los Alamos, NM; Devlin, David [Santa Fe, NM; Barbero, Robert S [Santa Cruz, NM; Carrera, Martin E [Naperville, IL; Colling, Craig W [Warrenville, IL

2010-08-10

Light hydrocarbon enrichment is accomplished using a vertically oriented distillation column having a plurality of vertically oriented, nonselective micro/mesoporous hollow fibers. Vapor having, for example, both propylene and propane is sent upward through the distillation column in between the hollow fibers. Vapor exits neat the top of the column and is condensed to form a liquid phase that is directed back downward through the lumen of the hollow fibers. As vapor continues to ascend and liquid continues to countercurrently descend, the liquid at the bottom of the column becomes enriched in a higher boiling point, light hydrocarbon (propane, for example) and the vapor at the top becomes enriched in a lower boiling point light hydrocarbon (propylene, for example). The hollow fiber becomes wetted with liquid during the process.

Nutrient enrichment shifts mangrove height distribution: Implications for coastal woody encroachment.

Science.gov (United States)

Weaver, Carolyn A; Armitage, Anna R

2018-01-01

Global changes, such as increased temperatures and elevated CO2, are driving shifts in plant species distribution and dominance, like woody plant encroachment into grasslands. Local factors within these ecotones can influence the rate of regime shifts. Woody encroachment is occurring worldwide, though there has been limited research within coastal systems, where mangrove (woody shrub/tree) stands are expanding into salt marsh areas. Because coastal systems are exposed to various degrees of nutrient input, we investigated how nutrient enrichment may locally impact mangrove stand expansion and salt marsh displacement over time. We fertilized naturally co-occurring Avicennia germinans (black mangrove) and Spartina alterniflora (smooth cordgrass) stands in Port Aransas, TX, an area experiencing mangrove encroachment within the Northern Gulf of Mexico mangrove-marsh ecotone. After four growing seasons (2010-2013) of continuous fertilization, Avicennia was more positively influenced by nutrient enrichment than Spartina. Most notably, fertilized plots had a higher density of taller (> 0.5 m) mangroves and mangrove maximum height was 46% taller than in control plots. Fertilization may promote an increase in mangrove stand expansion within the mangrove-marsh ecotone by shifting Avicennia height distribution. Avicennia individuals, which reach certain species-specific height thresholds, have reduced negative neighbor effects and have higher resilience to freezing temperatures, which may increase mangrove competitive advantage over marsh grass. Therefore, we propose that nutrient enrichment, which augments mangrove height, could act locally as a positive feedback to mangrove encroachment, by reducing mangrove growth suppression factors, thereby accelerating the rates of increased mangrove coverage and subsequent marsh displacement. Areas within the mangrove-marsh ecotone with high anthropogenic nutrient input may be at increased risk of a regime shift from grass to woody

Nutrient enrichment shifts mangrove height distribution: Implications for coastal woody encroachment

Science.gov (United States)

Armitage, Anna R.

2018-01-01

Global changes, such as increased temperatures and elevated CO2, are driving shifts in plant species distribution and dominance, like woody plant encroachment into grasslands. Local factors within these ecotones can influence the rate of regime shifts. Woody encroachment is occurring worldwide, though there has been limited research within coastal systems, where mangrove (woody shrub/tree) stands are expanding into salt marsh areas. Because coastal systems are exposed to various degrees of nutrient input, we investigated how nutrient enrichment may locally impact mangrove stand expansion and salt marsh displacement over time. We fertilized naturally co-occurring Avicennia germinans (black mangrove) and Spartina alterniflora (smooth cordgrass) stands in Port Aransas, TX, an area experiencing mangrove encroachment within the Northern Gulf of Mexico mangrove-marsh ecotone. After four growing seasons (2010–2013) of continuous fertilization, Avicennia was more positively influenced by nutrient enrichment than Spartina. Most notably, fertilized plots had a higher density of taller (> 0.5 m) mangroves and mangrove maximum height was 46% taller than in control plots. Fertilization may promote an increase in mangrove stand expansion within the mangrove-marsh ecotone by shifting Avicennia height distribution. Avicennia individuals, which reach certain species-specific height thresholds, have reduced negative neighbor effects and have higher resilience to freezing temperatures, which may increase mangrove competitive advantage over marsh grass. Therefore, we propose that nutrient enrichment, which augments mangrove height, could act locally as a positive feedback to mangrove encroachment, by reducing mangrove growth suppression factors, thereby accelerating the rates of increased mangrove coverage and subsequent marsh displacement. Areas within the mangrove-marsh ecotone with high anthropogenic nutrient input may be at increased risk of a regime shift from grass to woody

Uranium enrichment capacity: public versus private ownership

International Nuclear Information System (INIS)

Fraser, J.T.

1977-01-01

Continual growth of conventional nuclear capacity requires an assured supply of enriched uranium and, hence, potential expansion of domestic uranium enrichment capacity. The question of ownership of new enrichment capacity, i.e., public or private, entails not only the social-opportunity costs of alternative investments but also technical parameters of uranium utilization and advanced reactor development. Inclusion of risk preferences in both the public and private sectors produces interesting results in terms of optimal investment strategies with respect to choice of technology and scale of investment. Utilization of a nuclear fuel cycle requirements process model allows explicit specification of production technology. Integration of process model output with a least-cost investment model permits flexibility in parametric analysis. Results indicate minimum incentive for Government subsidy of a private enrichment sector through 2000 given moderate to low nuclear growth assumptions. The long-run scenario, to 2020, exhibits potentially greater incentives for private enrichment investment

Evaluation of the uranium enrichment demonstration plant project

International Nuclear Information System (INIS)

Sugitsue, Noritake

2001-01-01

In this report, the organization system of the uranium enrichment business is evaluated, based on the operation of the uranium enrichment demonstration plant. As a result, in uranium enrichment technology development or business, it was acknowledged that maintenance of the organization which has the Trinity of a research/engineering/operation was necessary in an industrialization stage by exceptional R and D cycle. Japan Nuclear Fuel Ltd. (JNFL) set up the Rokkashomura Aomori Uranium Enrichment Research and Development Center in November 2000. As a result, the system that company directly engaged in engineering development was prepared. And results obtained in this place is expected toward certain establishment of the uranium enrichment business of Japan. (author)

Uranium enrichment: a vital new industry

International Nuclear Information System (INIS)

1975-10-01

The energy problem facing the nation and the need for nuclear power are pointed out. Uranium enrichment and the demand for it are discussed. Reasons for, and obstacles to, private enrichment are outlined. The President's plan (including the Nuclear Fuel Assurance Act) is summarized

A dual protease approach for expression and affinity purification of recombinant proteins.

Science.gov (United States)

Raran-Kurussi, Sreejith; Waugh, David S

2016-07-01

We describe a new method for affinity purification of recombinant proteins using a dual protease protocol. Escherichia coli maltose binding protein (MBP) is employed as an N-terminal tag to increase the yield and solubility of its fusion partners. The MBP moiety is then removed by rhinovirus 3C protease, prior to purification, to yield an N-terminally His6-tagged protein. Proteins that are only temporarily rendered soluble by fusing them to MBP are readily identified at this stage because they will precipitate after the MBP tag is removed by 3C protease. The remaining soluble His6-tagged protein, if any, is subsequently purified by immobilized metal affinity chromatography (IMAC). Finally, the N-terminal His6 tag is removed by His6-tagged tobacco etch virus (TEV) protease to yield the native recombinant protein, and the His6-tagged contaminants are removed by adsorption during a second round of IMAC, leaving only the untagged recombinant protein in the column effluent. The generic strategy described here saves time and effort by removing insoluble aggregates at an early stage in the process while also reducing the tendency of MBP to "stick" to its fusion partners during affinity purification. Published by Elsevier Inc.

N-enriched multilayered porous carbon derived from natural casings for high-performance supercapacitors

Science.gov (United States)

Xu, Zongying; Li, Yu; Li, Dandan; Wang, Dawei; Zhao, Jing; Wang, Zhifeng; Banis, Mohammad N.; Hu, Yongfeng; Zhang, Huaihao

2018-06-01

In this study, N-enriched multilayered porous activated carbon (LPAC), using natural casings as precursor, was fabricated by a facile carbonization and subsequent KOH activation procedure. The influence of the mass ratio of KOH to carbonized material on pore-structure and surface element composition of LPACs was investigated by a variety of means, such as SEM, HRTEM, BET, Raman, XRD, XPS and XAS. Owing to the unique multilayered texture and nitrogen (N) and oxygen (O) rich feature of natural casings, the resulting LPACs possess interconnected and developed porous structure with N- and O-enriched functional groups, contributing to larger pseudocapacitance. With the rise of mass ratio, the specific surface area (SSA) and average pore size of LPACs increased. The final materials were endowed with a desirable SSA (3100 m2 g-1) and high N content (6.34 at.%). Meanwhile, N- and O-enriched LPAC-4 exhibited a high specific capacitance (307.5 F g-1 at a current density of 0.5 A g-1 in 6 M KOH aqueous solution), excellent rate performance (63.4% capacitance retention at 20 A g-1) and good cycling stability (7.1% capacitance loss after 5000 cycles). Furthermore, the assembled symmetrical supercapacitor (LPAC-4//LPAC-4) with a wide voltage window of 1.4 V delivered a remarkable energy density of 11.6 Wh kg-1 at a power density of 297 W kg-1. These results suggested that unique LPACs derived from natural casings are a promising material for supercapacitors.

INSIGHTS INTO PRE-ENRICHMENT OF STAR CLUSTERS AND SELF-ENRICHMENT OF DWARF GALAXIES FROM THEIR INTRINSIC METALLICITY DISPERSIONS

International Nuclear Information System (INIS)

Leaman, Ryan

2012-01-01

Star clusters are known to have smaller intrinsic metallicity spreads than dwarf galaxies due to their shorter star formation timescales. Here we use individual spectroscopic [Fe/H] measurements of stars in 19 Local Group dwarf galaxies, 13 Galactic open clusters, and 49 globular clusters to show that star cluster and dwarf galaxy linear metallicity distributions are binomial in form, with all objects showing strong correlations between their mean linear metallicity Z-bar and intrinsic spread in metallicity σ(Z) 2 . A plot of σ(Z) 2 versus Z-bar shows that the correlated relationships are offset for the dwarf galaxies from the star clusters. The common binomial nature of these linear metallicity distributions can be explained with a simple inhomogeneous chemical evolution model, where the star cluster and dwarf galaxy behavior in the σ(Z) 2 - Z-bar diagram is reproduced in terms of the number of enrichment events, covering fraction, and intrinsic size of the enriched regions. The inhomogeneity of the self-enrichment sets the slope for the observed dwarf galaxy σ(Z) 2 - Z-bar correlation. The offset of the star cluster sequence from that of the dwarf galaxies is due to pre-enrichment, and the slope of the star cluster sequence represents the remnant signature of the self-enriched history of their host galaxies. The offset can be used to separate star clusters from dwarf galaxies without a priori knowledge of their luminosity or dynamical mass. The application of the inhomogeneous model to the σ(Z) 2 - Z-bar relationship provides a numerical formalism to connect the self-enrichment and pre-enrichment between star clusters and dwarf galaxies using physically motivated chemical enrichment parameters. Therefore we suggest that the σ(Z) 2 - Z-bar relationship can provide insight into what drives the efficiency of star formation and chemical evolution in galaxies, and is an important prediction for galaxy simulation models to reproduce.

31 CFR 540.306 - Highly Enriched Uranium (HEU).

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false Highly Enriched Uranium (HEU). 540...) OFFICE OF FOREIGN ASSETS CONTROL, DEPARTMENT OF THE TREASURY HIGHLY ENRICHED URANIUM (HEU) AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.306 Highly Enriched Uranium (HEU). The term highly...

Comparative studies on mitochondria isolated from neuron-enriched and glia-enriched fractions of rabbit and beef brain.

Science.gov (United States)

Hamberger, A; Blomstrand, C; Lehninger, A L

1970-05-01

Fractions enriched in neuronal and glial cells were obtained from dispersions of whole beef brain and rabbit cerebral cortex by large-scale density gradient centrifugation procedures. The fractions were characterized by appropriate microscopic observation. Mitochondria were then isolated from these fractions by differential centrifugation of their homogenates. The two different types of mitochondria were characterized with respect to certain enzyme activities, respiratory rate, rate of protein synthesis, and their buoyant density in sucrose gradients. The mitochondria from the neuron-enriched fraction were distinguished by a higher rate of incorporation of amino acids into protein, higher cytochrome oxidase activity, and a higher buoyant density in sucrose density gradients. Mitochondria from the glia-enriched fraction showed relatively high monoamine oxidase and Na(+)- and K(+)-stimulated ATPase activities. The rates of oxidation of various substrates and the acceptor control ratios did not differ appreciably between the two types of mitochondria. The difference in the buoyant density of mitochondria isolated from the neuron-enriched and glia-enriched cell fractions was utilized in attempts to separate neuronal and glial mitochondria from the mixed mitochondria obtained from whole brain homogenates in shallow sucrose gradients. The appearance of two peaks of cytochrome oxidase, monoamine oxidase, and protein concentration in such gradients shows the potential feasibility of such an approach.

Enrichment and Molecular Analysis of Breast Cancer Disseminated Tumor Cells from Bone Marrow Using Microfiltration.

Directory of Open Access Journals (Sweden)

Sreeraj G Pillai

Full Text Available Molecular characterization of disseminated tumor cells (DTCs in the bone marrow (BM of breast cancer (BC patients has been hindered by their rarity. To enrich for these cells using an antigen-independent methodology, we have evaluated a size-based microfiltration device in combination with several downstream biomarker assays.BM aspirates were collected from healthy volunteers or BC patients. Healthy BM was mixed with a specified number of BC cells to calculate recovery and fold enrichment by microfiltration. Specimens were pre-filtered using a 70 μm mesh sieve and the effluent filtered through CellSieve microfilters. Captured cells were analyzed by immunocytochemistry (ICC, FISH for HER-2/neu gene amplification status, and RNA in situ hybridization (RISH. Cells eluted from the filter were used for RNA isolation and subsequent qRT-PCR analysis for DTC biomarker gene expression.Filtering an average of 14×106 nucleated BM cells yielded approximately 17-21×103 residual BM cells. In the BC cell spiking experiments, an average of 87% (range 84-92% of tumor cells were recovered with approximately 170- to 400-fold enrichment. Captured BC cells from patients co-stained for cytokeratin and EpCAM, but not CD45 by ICC. RNA yields from 4 ml of patient BM after filtration averaged 135ng per 10 million BM cells filtered with an average RNA Integrity Number (RIN of 5.3. DTC-associated gene expression was detected by both qRT-PCR and RISH in filtered spiked or BC patient specimens but, not in control filtered normal BM.We have tested a microfiltration technique for enrichment of BM DTCs. DTC capture efficiency was shown to range from 84.3% to 92.1% with up to 400-fold enrichment using model BC cell lines. In patients, recovered DTCs can be identified and distinguished from normal BM cells using multiple antibody-, DNA-, and RNA-based biomarker assays.

Composting of a crop residue through treatment with microorganisms and subsequent vermicomposting

Energy Technology Data Exchange (ETDEWEB)

Singh, A.; Sharma, S. [Indian Institute of Technology, New Delhi (India). Centre for Rural Development and Technology

2002-11-01

Preliminary studies were conducted on wheat straw to test the technical viability of an integrated system of composting, with bioinoculants and subsequent vermicomposting, to overcome the problem of lignocellulosic waste degradation, especially during the winter season. Wheat straw was pre-decomposed for 40 days by inoculating it with Pleurotus sajor-caju, Trichoderma harzianum, Aspergillus niger and Azotobacter chroococcum in different combinations. This was followed by vermicomposting for 30 days. Chemical analysis of the samples showed a significant decrease in cellulose, hemicellulose and lignin contents during pre-decomposition and vermicomposting. The N, P, K content increased significantly during pre-decomposition with bioinoculants. The best quality compost, based on chemical analysis, was prepared where the substrate was treated with all the four bioinoculants together followed by vermicomposting. Results indicated that the combination of both the systems reduced the overall time required for composting and accelerated the composting of ligno-cellulosic waste during the winter season besides producing a nutrient-enriched compost product. (author)

Enriched uranium recovery flowsheet improvements

International Nuclear Information System (INIS)

Holt, D.L.

1986-01-01

Savannah River uses 7.5% TBP to recover and purify enriched uranium. Adequate decontamination from fission products is necessary to reduce personnel exposure and to ensure that the enriched uranium product meets specifications. Initial decontamination of the enriched uranium from the fission products is carried out in the 1A bank, 16 stages of mixer-settlers. Separation of the enriched uranium from the fission product, 95 Zr, has been adequate, but excessive solvent degradation caused by the long phase contact times in the mixer-settlers has limited the 95 Zr decontamination factor (DF). An experimental program is investigating the replacement of the current 1A bank with either centrifugal contactors or a combination of centrifugal contactors and mixer-settlers. Experimental work completed has compared laboratory-scale centrifugal contactors and mixer-settlers for 95 Zr removal efficiencies. Feed solutions spiked with actual plant solutions were used. The 95 Zr DF was significantly better in the mixer-settlers than in the centrifugal contactors. As a result of this experimental study, a hybrid equipment flowsheet has been proposed for plant use. The hybrid equipment flowsheet combines the advantages of both types of solvent extraction equipment. Centrifugal contactors would be utilized in the extraction and initial scrub sections, followed by additional scrub stages of mixer-settlers

Stable isotope enrichment by thermal diffusion

International Nuclear Information System (INIS)

Vasaru, Gheorghe

2003-01-01

Thermal diffusion (TD) in both gaseous and liquid phase has been the subject of extensive experimental and theoretical investigations, especially after the invention by K. Clusius and G. Dickel of the thermal diffusion column, sixty years ago. This paper gives a brief overview of the most important applications and developments of this transport phenomenon for enrichment of 13 C and of some noble gases isotopes in our institute. The results of calculations of the transport coefficients H and K for a concentric tube type TD column, operated with methane as process gas, are presented. Static separation factor at equilibrium vs gas pressure has been calculated for various molecular models. The experimental separation factors for different gas pressure were found to be consistent with those calculated for the inverse power repulsion model and the Lennard-Jones model. The most important characteristics of a seven-stage cascade consisting of 19 TD columns of concentric tube type are given. This system has been constructed and successfully operated at a temperature of 673 K and produces an enrichment of methane of natural isotopic 13 C abundance, up to the concentration of 25% 13 CH 4 . Enrichment of the noble gases isotopes implies: - a . Enrichment of 20 Ne and 22 Ne in a eight-stage cascade consisting of 8 TD columns; - b. enrichment of 46 Ar in a seven-stage cascade consisting of TD columns and finally; - c. enrichment of 78 Kr and 86 Kr in a fifteen-stage cascade, consisting of 35 TD columns. For all these installations we have adopted TD columns of hot wire type (4 m in length), operated at a temperature of 1073 K. (author)

MICROBIOLOGICAL AND NUTRITIONAL QUALITY OF WARANKASHI ENRICHED BREAD

Directory of Open Access Journals (Sweden)

O. E. Dudu

2012-08-01

Full Text Available The study was carried out to determine the microbiological and nutritional quality, organoleptic, rheological and textural effect as well as the effect on the shelf life of wheat bread enriched with West African cottage cheese (warankashi at different substitution levels (1 %, 3 % and 5 %. The protein and fat content of wheat bread significantly increased but carbohydrate levels decreased significantly as enrichment with Warankashi increased. The amino acid profile of the wheat bread increased with increasing enrichment. The incorporation of Warankashi into wheat flour affected the rheological and textural properties of wheat flour; the rate of water absorption of the wheat flour decreased as Warankashi incorporation levels increased. Also, the dough stability time of the enriched flours was lesser than that of the wheat flour. The 3 % enrichment level had the highest dough consistency (520 BU. The extensibility of 1 % and 3 % wara bread dough were the same while that of wheat flour bread and 5 % Warankashi were the same. The 3 % wara bread dough had the highest resistance to extension. Shelf life of the bread remained unaffected by Warankashi incorporation but the rate of bacteria and fungi (yeast and mould growth decreased significantly (P < 0.05 as enrichment levels increased. There was no significant difference between the organoleptic properties of wheat bread to that of the enriched breads but the 3 % Warankshi enriched bread had the highest consumer acceptability.

Enrichment of omnivorous cercozoan nanoflagellates from coastal Baltic Sea waters.

Directory of Open Access Journals (Sweden)

Kasia Piwosz

Full Text Available Free-living nano-sized flagellates are important bacterivores in aquatic habitats. However, some slightly larger forms can also be omnivorous, i.e., forage upon both bacterial and eukaryotic resources. This hitherto largely ignored feeding mode may have pronounced implications for the interpretation of experiments about protistan bacterivory. We followed the response of an uncultured group of omnivorous cercozoan nanoflagellates from the Novel Clade 2 (Cerc_BAL02 to experimental food web manipulation in samples from the Gulf of Gdańsk (Southern Baltic Sea. Seawater was either prefiltered through 5 µm filters to exclude larger predators of nanoflagellates (F-treatment, or prefiltered and subsequently 1∶10 diluted with sterile seawater (F+D-treatment to stimulate the growth of both, flagellates and bacteria. Initially, Cerc_BAL02 were rapidly enriched under both conditions. They foraged on both, eukaryotic prey and bacteria, and were highly competitive at low concentrations of food. However, these omnivores were later only successful in the F+D treatment, where they eventually represented almost one fifth of all aplastidic nanoflagellates. By contrast, their numbers stagnated in the F-treatment, possibly due to top-down control by a concomitant bloom of other, unidentified flagellates. In analogy with observations about the enrichment of opportunistically growing bacteria in comparable experimental setups we suggest that the low numbers of omnivorous Cerc_Bal02 flagellates in waters of the Gulf of Gdańsk might also be related to their vulnerability to grazing pressure.

Matching Subsequences in Trees

DEFF Research Database (Denmark)

Bille, Philip; Gørtz, Inge Li

2009-01-01

Given two rooted, labeled trees P and T the tree path subsequence problem is to determine which paths in P are subsequences of which paths in T. Here a path begins at the root and ends at a leaf. In this paper we propose this problem as a useful query primitive for XML data, and provide new...

Safety aspects of gas centrifuge enrichment plants

International Nuclear Information System (INIS)

Hansen, A.H.

1987-01-01

Uranium enrichment by gas centrifuge is a commercially proven, viable technology. Gas centrifuge enrichment plant operations pose hazards that are also found in other industries as well as unique hazards as a result of processing and handling uranium hexafluoride and the handling of enriched uranium. Hazards also found in other industries included those posed by the use of high-speed rotating equipment and equipment handling by use of heavy-duty cranes. Hazards from high-speed rotating equipment are associated with the operation of the gas centrifuges themselves and with the operation of the uranium hexafluoride compressors in the tail withdrawal system. These and related hazards are discussed. It is included that commercial gas centrifuge enrichment plants have been designed to operate safely

Uranium enrichment: an evolving market

International Nuclear Information System (INIS)

Longenecker, J.; Witzel, R.

1997-01-01

With over half of the world uranium enrichment market uncommitted to any supplier early in the next century, competition is certain to be fierce. In the meantime the outlood remains unclear, with the market dominated by a number of developments -privatisation of the United States Enrichment Corp (USEC), increasing availability of Russian and US military inventories, the deployment of advanced technology and the closure of nuclear power plants due to deregulation. (author)

Enrichment of Sc{sub 2}O{sub 3} and TiO{sub 2} from bauxite ore residues

Energy Technology Data Exchange (ETDEWEB)

Deng, Bona; Li, Guanghui, E-mail: liguangh@csu.edu.cn; Luo, Jun; Ye, Qing; Liu, Mingxia; Peng, Zhiwei; Jiang, Tao

2017-06-05

Highlights: • Sc{sub 2}O{sub 3} and TiO{sub 2} from bauxite ore residue were successfully enriched. • H{sub 3}PO{sub 4} and NaOH were efficient for enriching Sc{sub 2}O{sub 3} and TiO{sub 2} by removing SiO{sub 2}, Al{sub 2}O{sub 3}, and partial Fe{sub 2}O{sub 3} and CaO. • Enriching mechanism of Sc{sub 2}O{sub 3} and TiO{sub 2} was explicitly explained. - Abstract: As a major byproduct generated in the alumina industry, bauxite ore residue is an important reserve of scandium and titanium. In this study, the feasibility and mechanism of enriching Sc{sub 2}O{sub 3} and TiO{sub 2} from a non-magnetic material, which was obtained from carbothermal reductive roasting and magnetic separation of bauxite ore residue, were investigated based on a two-step (acidic and alkali) leaching process. It was revealed that approximately 78% SiO{sub 2} and 30–40% of CaO, FeO and Al{sub 2}O{sub 3} were removed from a non-magnetic material with 0.0134 wt.% Sc{sub 2}O{sub 3} and 7.64 wt.% TiO{sub 2} by phosphoric acidic leaching, while about 95% Al{sub 2}O{sub 3} and P{sub 2}O{sub 5} were further leached by subsequent sodium hydroxide leaching of the upper-stream leach residue. A Sc{sub 2}O{sub 3}-, TiO{sub 2}- rich material containing 0.044 wt.% Sc{sub 2}O{sub 3} and 25.5 wt.% TiO{sub 2} was obtained, the recovery and the enrichment factor of Sc{sub 2}O{sub 3} and TiO{sub 2} were about 85% and 5, respectively. The enrichment of Sc{sub 2}O{sub 3} was attributed to higher pH (>3.3) of phosphoric acid solution than its dissolution pH{sup 0}, and the enrichment of TiO{sub 2} was mainly associated with the insoluble perovskite (CaTiO{sub 3}) in the acidic solution at ambient temperature. As Sc{sub 2}O{sub 3} and TiO{sub 2} cannot be dissolved in the alkali solution, they were further enriched in the leach residue.

A theory of surface enrichment in ordered alloys

NARCIS (Netherlands)

Santen, van R.A.; Sachtler, W.M.H.

1974-01-01

A simple theory was developed to explain exptl. data on surface enrichment in Pt3Sn. The computed surface enrichment is in accord with exptl. findings. The theory predicts that in the Pt3Sn system enrichment occurs by interchange of atoms of the element with the lower heat of sublimation from the

Detection of uranium enrichment activities using environmental monitoring techniques

International Nuclear Information System (INIS)

Belew, W.L.; Carter, J.A.; Smith, D.H.; Walker, R.L.

1993-01-01

Uranium enrichment processes have the capability of producing weapons-grade material in the form of highly enriched uranium. Thus, detection of undeclared uranium enrichment activities is an international safeguards concern. The uranium separation technologies currently in use employ UF 6 gas as a separation medium, and trace quantities of enriched uranium are inevitably released to the environment from these facilities. The isotopic content of uranium in the vegetation, soil, and water near the plant site will be altered by these releases and can provide a signature for detecting the presence of enriched uranium activities. This paper discusses environmental sampling and analytical procedures that have been used for the detection of uranium enrichment facilities and possible safeguards applications of these techniques

How is uranium supply affecting enrichment?

International Nuclear Information System (INIS)

Steve Kidd

2007-01-01

As a result of the enlivened uranium market, momentum has in turn picked up in the enrichment sector. What are the consequences of higher uranium prices? There is, of course, a link between uranium and enrichment supply to the extent that they are at least partial substitutes. On the enrichment supply side, the most obvious feature is the gradual replacement of the old gas diffusion facilities of Usec in the USA and EURODIF in France with more modern and economical centrifuge plants. Assuming Usec can overcome the financing and technical issues surrounding its plans, the last gas diffusion capacity should disappear around 2015 and the entire enrichment market should then be using centrifuges. On the commercial side, the key anticipated developments are mostly in Russia. Although there should still continue to be substantial quantities of surplus Russian HEU available for down blending in the period beyond 2013, it is now reasonable to expect that it will be mostly consumed by internal needs, to fuel Russian-origin reactors both at home and in export markets such as China and India. Finally, as a key sensitive area for the non-proliferation of nuclear weapons, the enrichment sector is likely to be a central point of the new international arrangements which must be developed to support a buoyant nuclear sector throughout this century.

PACS/IMAC technology assessment

OpenAIRE

Schilling, Ronald B.

1997-01-01

According to Peter Ogle of Digital Imaging (San Francisco, CA), “Radiologists should help identify common values for the use of information technology in medicine.” Achieving a set of common values often requires a framework for organizing the thought process involved. That is the focus of this article in addressing the subject of picture archiving and communication system (PACS) technology assessment.

Toward a predictive theory for environmental enrichment.

Science.gov (United States)

Watters, Jason V

2009-11-01

There have been many applications of and successes with environmental enrichment for captive animals. The theoretical spine upon which much enrichment work hangs largely describes why enrichment should work. Yet, there remains no clear understanding of how enrichment should be applied to achieve the most beneficial results. This lack of understanding may stem in part from the assumptions that underlie the application of enrichment by practitioners. These assumptions are derived from an understanding that giving animals choice and control in their environment stimulates their motivation to perform behaviors that may indicate a heightened state of well-being. Learning theory provides a means to question the manner in which these constructs are routinely applied, and converting learning theory's findings to optimality predictions suggests a particularly vexing paradox-that motivation to perform appears to be maintained best when acquiring a payoff for expressing the behavior is uncertain. This effect occurs even when the actual value of the payoff is the same for all schedules of certainty of payoff acquisition. The paradox can be resolved by invoking rewards of an alternative type, such as cognitive rewards, or through an understanding of how the average payoff changes with changes in the probability of reward. This model, with measures of the average change of the payoff, suggests testable scenarios by which practitioners can measure the quality of environmental uncertainty in enrichment programs.

Oak Ridge National Laboratory's isotope enrichment program

International Nuclear Information System (INIS)

Tracy, J.G.; Aaron, W.C.

1997-01-01

The Isotope Enrichment Program (IEP) at Oak Ridge National Laboratory (ORNL) is responsible for the production and distribution of ∼225 enriched stable isotopes from 50 multi-isotopic elements. In addition, ORNL distributes enriched actinide isotopes and provides extensive physical- and chemical-form processing of enriched isotopes to meet customer requirements. For more than 50 yr, ORNL has been a major provider of enriched isotopes and isotope-related services to research, medical, and industrial institutions throughout the world. Consolidation of the Isotope Distribution Office (IDO), the Isotope Research Materials Laboratory (IRML), and the stable isotope inventories in the Isotope Enrichment Facility (IEF) have improved operational efficiencies and customer services. Recent changes in the IEP have included adopting policies for long-term contracts, which offer program stability and pricing advantages for the customer, and prorated service charges, which greatly improve pricing to the small research users. The former U.S. Department of Energy (DOE) Loan Program has been converted to a lease program, which makes large-quantity or very expensive isotopes available for nondestructive research at a nominal cost. Current efforts are being pursued to improve and expand the isotope separation capabilities as well as the extensive chemical- and physical-form processing that now exists. The IEF's quality management system is ISO 9002 registered and accredited in the United States, Canada, and Europe

The isotopic enrichment of uranium in 1979

International Nuclear Information System (INIS)

Baron, M.

1979-01-01

The Eurodif uranium enrichment plant built on the Tricastin site is described. The uranium isotope separation plants in service abroad are presented. The main characteristics of the international enrichment market are defined [fr

Network-based functional enrichment

Directory of Open Access Journals (Sweden)

Poirel Christopher L

2011-11-01

Full Text Available Abstract Background Many methods have been developed to infer and reason about molecular interaction networks. These approaches often yield networks with hundreds or thousands of nodes and up to an order of magnitude more edges. It is often desirable to summarize the biological information in such networks. A very common approach is to use gene function enrichment analysis for this task. A major drawback of this method is that it ignores information about the edges in the network being analyzed, i.e., it treats the network simply as a set of genes. In this paper, we introduce a novel method for functional enrichment that explicitly takes network interactions into account. Results Our approach naturally generalizes Fisher’s exact test, a gene set-based technique. Given a function of interest, we compute the subgraph of the network induced by genes annotated to this function. We use the sequence of sizes of the connected components of this sub-network to estimate its connectivity. We estimate the statistical significance of the connectivity empirically by a permutation test. We present three applications of our method: i determine which functions are enriched in a given network, ii given a network and an interesting sub-network of genes within that network, determine which functions are enriched in the sub-network, and iii given two networks, determine the functions for which the connectivity improves when we merge the second network into the first. Through these applications, we show that our approach is a natural alternative to network clustering algorithms. Conclusions We presented a novel approach to functional enrichment that takes into account the pairwise relationships among genes annotated by a particular function. Each of the three applications discovers highly relevant functions. We used our methods to study biological data from three different organisms. Our results demonstrate the wide applicability of our methods. Our algorithms are

Method and apparatus for enrichment or upgrading heavy water

International Nuclear Information System (INIS)

Butler, J.P.; Hammerli, M.

1979-01-01

A method and apparatus for upgrading and final enrichment of heavy water are described, comprising means for contacting partially enriched heavy water feed in a catalyst column with hydrogen gas (essentially D 2 ) originating in an electrolysis cell so as to enrich the feed water with deuterium extracted from the electrolytic hydrogen gas and means for passing the deuterium enriched water to the electrolysis cell. (author)

EURODIF: the uranium enrichment by gaseous diffusion

International Nuclear Information System (INIS)

Rougeau, J.P.

1981-01-01

During the seventies the nuclear power programme had an extremely rapid growth rate which entailed to increase the world uranium enrichment capacity. EURODIF is the largest undertaking in this field. This multinational joint venture built and now operates and enrichment plant using the gaseous diffusion process at Tricastin (France). This plant is delivering low enriched uranium since two years and has contracted about 110 million SWU's till 1990. Description, current activity and prospects are given in the paper. (Author) [pt

Unattended safeguards instrumentation at centrifuge enrichment plants

International Nuclear Information System (INIS)

Smith, L. Eric; Lebrun, Alain R.; Labella, Rocco

2014-01-01

As global uranium enrichment capacity under international safeguards expands, the International Atomic Energy Agency (IAEA) is challenged to develop effective safeguards approaches at gaseous centrifuge enrichment plants, particularly high‑capacity plants, while working within budgetary constraints. New safeguards approaches should meet the high‑level verification objectives for such facilities (i.e., timely detection of: diversion of declared material, excess production beyond declared amounts, and production of enrichment levels higher than declared), but should also strive for efficiency advantages in implementation, for both the IAEA and operators. Under the Agency’s State- level approach to safeguards implementation, the Agency needs a flexible toolbox of technologies, allowing tailoring of safeguards measures for each individual enrichment facility. In this paper, the potential roles and development status for three different types of unattended measurement instrumentation are discussed. On‑Line Enrichment Monitors (OLEM) could provide continuous enrichment measurement for 100% of the declared gas flowing through unit header pipes. Unattended Cylinder Verification Stations (UCVS) could provide unattended verification of the declared uranium mass and enrichment of 100% of the cylinders moving through the plant, but also apply and verify an ‘NDA Fingerprint’ to preserve verification knowledge on the contents of each cylinder throughout its life in the facility. Sharing of the operator’s load cell signals from feed and withdrawal stations could count all cylinders introduced to the process and provide periodic monitoring of the uranium mass balance for in‑process material. The integration of load cell, OLEM and UCVS data streams offers the possibility for 100% verification of declared cylinder flow, and enables the periodic verification of the declared 235 U mass balance in the plant. These new capabilities would enhance the IAEA�

Curriculum enrichment through indigenous Zulu games | Roux ...

African Journals Online (AJOL)

Curriculum enrichment through indigenous Zulu games. ... 1997). The aim of the study was to document and analyze indigenous Zulu games for possible curriculum enrichment of physical ... AJOL African Journals Online. HOW TO USE AJOL.

Unjust enrichment in business law

OpenAIRE

Vydrová, Zuzana

2016-01-01

This thesis analyses the concept of unjust enrichment under the business law. First of all the thesis explains the term of business law. Business law is a complex of legal rules concerning the contractual relationships between entrepreneurs arising from their business activities. Business law is a comprehensive field of law which extends into many other fields of law, both private and public law. Equally the regulation of unjust enrichment within the business law expands into many other laws ...

Uranium enrichment by centrifuge in Japan

International Nuclear Information System (INIS)

Watanabe, T.; Murase, T.

1977-01-01

The demand for enriched uranium is on the increase with nuclear power capacity in which the LWR predominates and is estimated to exceed the supply from the present facilities in the world in less than ten years. Therefore, the basic strategy for enriched uranium is investigated on the following three-point long-range program in Japan: 1. To continue negotiations to extend the current allocation by the long-term contract; 2. To seek active participation in international enrichment projects; and 3. To make efforts to develop uranium enrichment technology and to construct inland facilities. On this basis, a vigorous development program of gas centrigue process for industrialization was launched out in 1972 as a national project. Ever since substantial progress in this field has been made and development works have been increased year after year. At present, a concrete plan of a pilot plant is taking shape. Up to now, several types of centrifuges were developed, of which some were completed as prototype models, and subjected to life tests and also to extensive earthquake-resistivity tests for the characteristics of Japanese geological condition. An enrichment plant is composed of so many centrifuges that the installation and piping system of centrifuges is an important factor which has an effect on plant economy and reliability. Two types of the experimental cascade were constructed in Japan. One has been in operation since 1973, and the other since 1975. Valuable empirical data have been accumulated on cascade characteristics, maintenance scheme and so on. It will be important for the coming plants to have a flexibility to escalation of labor and energy cost, or to variation of the separative work requirement and further. An economic prospect of centrifuge enrichment process is presented

Subsequence Automata with Default Transitions

DEFF Research Database (Denmark)

Bille, Philip; Gørtz, Inge Li; Skjoldjensen, Frederik Rye

2016-01-01

of states and transitions) of the subsequence automaton is O(nσ) and that this bound is asymptotically optimal. In this paper, we consider subsequence automata with default transitions, that is, special transitions to be taken only if none of the regular transitions match the current character, and which do...... not consume the current character. We show that with default transitions, much smaller subsequence automata are possible, and provide a full trade-off between the size of the automaton and the delay, i.e., the maximum number of consecutive default transitions followed before consuming a character......(nσ) and delay O(1), thus matching the bound for the standard subsequence automaton construction. The key component of our result is a novel hierarchical automata construction of independent interest....

US enrichment reduction studies

International Nuclear Information System (INIS)

1979-06-01

A major national program, the Reduced Enrichment Research and Test Reactor (RERTR) Program, is currently under way in the U.S., centered at the Argonne National Laboratory (ANL), to reduce the potential of research and test reactor fuels for increasing the proliferation of nuclear explosive devices. The main objective of the program is to provide the technical means by which the uranium enrichment to be used in these reactors can be reduced to less than 20% without significant economic and performance penalties. The criteria, basis and goals of the program are consistent with the results of a number of case studies which have been performed as part of the program

Advanced uranium enrichment processes

International Nuclear Information System (INIS)

Clerc, M.; Plurien, P.

1986-01-01

Three advanced Uranium enrichment processes are dealt with in the report: AVLIS (Atomic Vapour LASER Isotope Separation), MLIS (Molecular LASER Isotope Separation) and PSP (Plasma Separation Process). The description of the physical and technical features of the processes constitutes a major part of the report. If further presents comparisons with existing industrially used enrichment technologies, gives information on actual development programmes and budgets and ends with a chapter on perspectives and conclusions. An extensive bibliography of the relevant open literature is added to the different subjects discussed. The report was drawn up by the nuclear research Centre (CEA) Saclay on behalf of the Commission of the European Communities

Low-resolution gamma-ray measurements of uranium enrichment

International Nuclear Information System (INIS)

Sprinkle, J.K. Jr.; Christiansen, A.; Cole, R.; Collins, M.L.

1996-01-01

Facilities that process special nuclear material perform periodic inventories. In bulk facilities that process low-enriched uranium, these inventories and their audits are based primarily on weight and enrichment measurements. Enrichment measurements determine the 211 U weight fraction of the uranium compound from the passive gamma-ray emissions of the sample. Both international inspectors and facility operators rely on the capability to make in-field gamma-ray measurements of uranium enrichment. These users require rapid, portable measurement capability. Some in-field measurements have been biased, forcing the inspectors to resort to high-resolution measurements or mass spectrometry to accomplish their goals

A consideration on laser enrichment module

International Nuclear Information System (INIS)

Arisawa, Takashi; Shiba, Koreyuki

1983-09-01

Several problems are discussed for designing a simplified enrichment module based on Atomic Laser Isotope Separation Method, which involve the vaporization of metal, laser excitation, laser ionization and ion recovery. The conditions at which the consumed energy has the minimum value are obtained by calculating the specific energy consumption for producing unit amount of enriched products. It is found that there should be an appropriate relationship between the processing atomic density and the electrode gap in order to avoid the enrichment loss caused by the charge exchange during the ion recovery. Moreover it is also found that this relation depends on the electrode length measured along both the atomic beam direction and the laser beam direction. (author)

21 CFR 137.350 - Enriched rice.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Enriched rice. 137.350 Section 137.350 Food and... Related Products § 137.350 Enriched rice. (a) The foods for which definitions and standards of identity are prescribed by this section are forms of milled rice (except rice coated with talc and glucose and...

Theoretical studies aiming at the IEA-R1 reactor core conversion from high U-235 enrichment to low U-235 enrichment

International Nuclear Information System (INIS)

Frajndlich, R.

1982-01-01

The research reactors, of which the fuel elements are of MTR type, functions presently, almost in their majority with high U-235 enrichment. The fear that those fuel elements might generate a considerabLe proliferation of nuclear weapons rendered almost mandatory the conversion of highly enriched fuel elements to a low U-235 enrichment. As the IEA-R1 reactor of IPEN is operating with highly enriched fuel elements a study aiming at this conversion was done. The problems related to the conversion and the results obtained, demonstrated the technical viabilty for its realization. (E.G.) [pt

Axial blanket enrichment optimization of the NPP Krsko fuel

International Nuclear Information System (INIS)

Kromar, M.; Kurincic, B.

2001-01-01

In this paper optimal axial blanket enrichment of the NPP Krsko fuel is investigated. Since the optimization is dictated by economic categories that can significantly vary in time, two step approach is applied. In the first step simple relationship between the equivalent change in enrichment of axial blankets and central fuel region is established. The relationship is afterwards processed with economic criteria and constraints to obtain optimal axial blanket enrichment. In the analysis realistic NPP Krsko conditions are considered. Except for the fuel enrichment all other fuel characteristics are the same as in the fuel used in the few most recent cycles. A typical reload cycle after the plant power uprate is examined. Analysis has shown that the current blanket enrichment is close to the optimal. Blanket enrichment reduction results in an approximately 100 000 US$ savings per fuel cycle.(author)

Subsequence automata with default transitions

DEFF Research Database (Denmark)

Bille, Philip; Gørtz, Inge Li; Skjoldjensen, Frederik Rye

2017-01-01

of states and transitions) of the subsequence automaton is O(nσ) and that this bound is asymptotically optimal. In this paper, we consider subsequence automata with default transitions, that is, special transitions to be taken only if none of the regular transitions match the current character, and which do...... not consume the current character. We show that with default transitions, much smaller subsequence automata are possible, and provide a full trade-off between the size of the automaton and the delay, i.e., the maximum number of consecutive default transitions followed before consuming a character......(1), thus matching the bound for the standard subsequence automaton construction. Finally, we generalize the result to multiple strings. The key component of our result is a novel hierarchical automata construction of independent interest....

Reducing enrichment of fuel for research reactors

International Nuclear Information System (INIS)

Kanda, Keiji; Matsuura, Shojiro.

1980-01-01

In research reactors, highly enriched uranium (HEU) is used as fuel for their purposes of operation. However, the United States strongly required in 1977 that these HEU should be replaced by low enrichment uranium (LEU) of 20% or less, or even in unavoidable cases, it should be replaced by medium enrichment uranium (MEU). INFCE (International Nuclear Fuel Cycle Evaluation) which started its activity just at that time decided to discuss this problem in the research reactor group of No. 8 sectional committee. Japan has been able to forward the work, taking a leading part in the international opinion because she has taken the countermeasures quickly. INFCE investigated the problem along the lines of policy that the possibility of reducing the degree of enrichment should be limited to the degree in which the core structures and equipments of research reactors will be modified as little as possible, and the change of fuel element geometry will be done within the permissible thermohydrodynamic capacity, and concluded that it might be possible in near future to reduce the degree of enrichment to about 45% MEU, while the reduction to 20% LEU might require considerable research, development and verification. On the other hand, the joint researches by Kyoto University and ANL (Argonne National Laboratory) and by Japan Atomic Energy Research Institute and ANL are being continued. IAEA has edited the guidebook (IAEA-TECDOC-233) for reducing the degree of enrichment for developing countries. (Wakatsuki, Y.)

Negative enrichment by immunomagnetic nanobeads for unbiased characterization of circulating tumor cells from peripheral blood of cancer patients

Directory of Open Access Journals (Sweden)

Tinhofer Ingeborg

2011-05-01

Full Text Available Abstract Background A limitation of positive selection strategies to enrich for circulating tumor cells (CTCs is that there might be CTCs with insufficient expression of the surface target marker which may be missed by the procedure. We optimized a method for enrichment, subsequent detection and characterization of CTCs based on depletion of the leukocyte fraction. Methods The 2-step protocol was developed for processing 20 mL blood and based on red blood cell lysis followed by leukocyte depletion. The remaining material was stained with the epithelial markers EpCAM and cytokeratin (CK 7/8 or for the melanoma marker HMW-MAA/MCSP. CTCs were detected by flow cytometry. CTCs enriched from blood of patients with carcinoma were defined as EpCAM+CK+CD45-. CTCs enriched from blood of patients with melanoma were defined as MCSP+CD45-. One-hundred-sixteen consecutive blood samples from 70 patients with metastatic carcinomas (n = 48 or metastatic melanoma (n = 22 were analyzed. Results CTCs were detected in 47 of 84 blood samples (56% drawn from carcinoma patients, and in 17 of 32 samples (53% from melanoma patients. CD45-EpCAM-CK+ was detected in pleural effusion specimens, as well as in peripheral blood samples of patients with NSCLC. EpCAM-CK+ cells have been successfully cultured and passaged longer than six months suggesting their neoplastic origin. This was confirmed by CGH. By defining CTCs in carcinoma patients as CD45-CK+ and/or EpCAM+, the detection rate increased to 73% (61/84. Conclusion Enriching CTCs using CD45 depletion allowed for detection of epithelial cancer cells not displaying the classical phenotype. This potentially leads to a more accurate estimation of the number of CTCs. If detection of CTCs without a classical epithelial phenotype has clinical relevance need to be determined.

Hammond Postulate Mirroring Enables Enantiomeric Enrichment of Phosphorus Compounds via Two Thermodynamically Interconnected Sequential Stereoselective Processes.

Science.gov (United States)

Rajendran, Kamalraj V; Nikitin, Kirill V; Gilheany, Declan G

2015-07-29

The dynamic resolution of tertiary phosphines and phosphine oxides was monitored by NMR spectroscopy. It was found that the stereoselectivity is set during the formation of the diastereomeric alkoxyphosphonium salts (DAPS), such that their initial diastereomeric excess (de) limits the final enantiomeric excess (ee) of any phosphorus products derived from them. However, (31)P NMR monitoring of the spontaneous thermal decomposition of the DAPS shows consistent diastereomeric self-enrichment, indicating a higher rate constant for decomposition of the minor diastereomer. This crucial observation was confirmed by reductive trapping of the unreacted enriched DAPS with lithium tri-sec-butylborohydride (commercially distributed as L-Selectride reagent) at different time intervals after the start of reaction, which gives progressively higher ee of the phosphine product with time. It is proposed that the Hammond postulate operates for both formation and decomposition of DAPS intermediate so that the lower rate of formation and faster subsequent collapse of the minor isomer are thermodynamically linked. This kinetic enhancement of kinetic resolution furnishes up to 97% ee product.

Protein selectivity with immobilized metal ion-tacn sorbents: chromatographic studies with human serum proteins and several other globular proteins.

Science.gov (United States)

Jiang, W; Graham, B; Spiccia, L; Hearn, M T

1998-01-01

The chromatographic selectivity of the immobilized chelate system, 1,4,7-triazocyclononane (tacn), complexed with the borderline metal ions Cu2+, Cr3+, Mn2+, Co2+, Zn2+, and Ni2+ has been investigated with hen egg white lysozyme, horse heart cytochrome c, and horse skeletal muscle myoglobin, as well as proteins present in partially fractionated preparations of human plasma. The effects of ionic strength and pH of the loading and elution buffers on protein selectivities of these new immobilized metal ion affinity chromatographic (IMAC) systems have been examined. The results confirm that immobilized Mn;pl-tacn sorbents exhibit a novel type of IMAC behavior with proteins. In particular, the chromatographic properties of these immobilized M(n+)-tacn ligand systems were significantly different compared to the IMAC behavior observed with other types of immobilized tri- and tetradentate chelating ligands, such as iminodiacetic acid, O-phosphoserine, or nitrilotriacetic acid, when complexed with borderline metal ions. The experimental results have consequently been evaluated in terms of the additional contributions to the interactive processes mediated by effects other than solely the conventional lone pair Lewis soft acid-Lewis soft base coordination interactions, typically found for the IMAC of proteins with borderline and soft metal ions, such as Cu2+ or Ni2+.

Managing public acceptance for a new enrichment facility

International Nuclear Information System (INIS)

Boyd, M.

1992-01-01

The Claiborne Enrichment Center has many first associated with it, and a solid nuclear-based community relations experience has been combined with fly-by-the-seat-of-your-pants techniques to successfully introduce a first-of-a-kind facility not only to Louisiana, but also to the US. The project is being developed by Louisiana Energy Services (LES), a limited partnership consisting of Urenco, the European enrichment consortium that operates centrifuge enrichment facilities in the United Kingdom, the Netherlands, and Germany; Fluor Daniel, an internationally known engineering and construction firm; and three utilities - Duke Power, Northern States Power, and Louisiana Power and Light (LP and L). Louisiana Energy will build the nation's first privately owned uranium enrichment facility. It will be the first commercial use of centrifuge technology for enrichment in the US. Some of the community relations challenges the project has had and their solutions are described

Future of uranium enrichment

International Nuclear Information System (INIS)

Hosmer, C.

1981-01-01

The increasing amount of separative work being done in government facilities to produce low-enriched uranium fuel for nuclear utilities again raises the question: should this business-type, industrial function be burned over the private industry. The idea is being looked at by the Reagan administration, but faces problems of national security as well as from the unique nature of the business. This article suggests that a joint government-private venture combining enriching, reprocessing, and waste disposal could be the answer. Further, a separate entity using advanced laser technology to deplete existing uranium tails and lease them for fertile blankets in breeder reactors might earn substantial revenues to help reduce the national debt

Uranium enrichment: investment options for the long term

International Nuclear Information System (INIS)

Anon.

1983-01-01

The US government supplies a major portion of the enriched uranium used to fuel most of the nuclear power plants that furnish electricity in the free world. As manager of the US uranium enrichment concern, the Department of Energy (DOE) is investigating a number of technological choices to improve enrichment service and remain a significant world supplier. The Congress will ultimately select a strategy for federal investment in the uranium enrichment enterprise. A fundamental policy choice between possible future roles - that of the free world's main supplier of enrichment services, and that of a mainly domestic supplier - will underlie any investment decision the Congress makes. The technological choices are gaseous diffusion, gas centrifuge, and atomic vapor laser isotope separation (AVLIS). A base plan and four alternatives were examined by DOE and the Congressional Budget Office. In terms of total enterprise costs, Option IV, ultimately relying on advanced gas centrifuges for enrichment services, would offer the most economic approach, with costs over the full projection period totaling $123.5 billion. Option III, ultimately relying on AVLIS without gas centrifuge enrichment or gaseous diffusion, falls next in the sequence, with costs of $128.2 billion. Options I and II, involving combinations of the gas centrifuge and AVLIS technologies, follow closely with costs of $128.7 and $129.6 billion. The base plan has costs of $136.8 billion over the projection period. 1 figure, 22 tables

Environmental Enrichment for Broiler Breeders: An Undeveloped Field

Directory of Open Access Journals (Sweden)

Anja B. Riber

2017-06-01

Full Text Available Welfare problems, such as hunger, frustration, aggression, and abnormal sexual behavior, are commonly found in broiler breeder production. To prevent or reduce these welfare problems, it has been suggested to provide stimulating enriched environments. We review the effect of the different types of environmental enrichment for broiler breeders, which have been described in the scientific literature, on behavior and welfare. Environmental enrichment is defined as an improvement of the environment of captive animals, which increases the behavioral opportunities of the animal and leads to improvements in biological function. This definition has been broadened to include practical and economic aspects as any enrichment strategy that adversely affects the health of animals (e.g., environmental hygiene, or that has too many economic or practical constraints will never be implemented on commercial farms and thus never benefit animals. Environmental enrichment for broiler breeders often has the purpose of satisfying the behavioral motivations for feeding and foraging, resting, and/or encouraging normal sexual behavior. Potentially successful enrichments for broiler breeders are elevated resting places, cover panels, and substrate (for broiler breeders housed in cage systems. However, most of the ideas for environmental enrichment for broiler breeders need to be further developed and studied with respect to the use, the effect on behavior and welfare, and the interaction with genotype and production system. In addition, information on practical use and the economics of the production system is often lacking although it is important for application in practice.

Measurement of the enrichment of uranium in the pipework of a gas centrifuge enrichment plant

International Nuclear Information System (INIS)

Packer, T.W.; Lees, E.W.; Close, D.; Nixon, K.V.; Pratt, J.C.; Strittmatter, R.

1985-01-01

The US and UK have been separately working on the development of a NDA instrument to determine the enrichment of gaseous UF 6 at low pressures in cascade header pipework in line with the conclusions of the Hexapartite Safeguards Project viz. the instrument is capable of making a ''go/no go'' decision of whether the enrichment is less than/greater than 20%. Recently, there has been a series of very useful technical exchanges of ideas and information between the two countries. This has led to a technical formulation for such an instrumentation based on γ-ray spectrometry which, although plant-specific in certain features, nevertheless is based on the same physical principles. Experimental results from commercially operating enrichment plants are very encouraging and indicate that a complete measurement including set up time on the pipe should be attainable in about 30 minutes when measuring pipes of diameter around 110 mm. 5 refs., 4 figs

Design, construction, and operation of a laboratory scale reactorfor the production of high-purity, isotopically enriched bulksilicon

Energy Technology Data Exchange (ETDEWEB)

Ager III, J.W.; Beeman, J.W.; Hansen, W.L.; Haller, E.E.

2004-12-20

The design and operation of a recirculating flow reactor designed to convert isotopically enriched silane to polycrystalline Si with high efficiency and chemical purity is described. The starting material is SiF{sub 4}, which is enriched in the desired isotope by a centrifuge method and subsequently converted to silane. In the reactor, the silane is decomposed to silicon on the surface of a graphite starter rod (3 mm diameter) heated to 700-750 C. Flow and gas composition (0.3-0.5% silane in hydrogen) are chosen to minimize the generation of particles by homogeneous nucleation of silane and to attain uniform deposition along the length of the rod. Growth rates are 5 {micro}m/min, and the conversion efficiency is greater than 95%. A typical run produces 35 gm of polycrystalline Si deposited along a 150 mm length of the rod. After removal of the starter rod, dislocation-free single crystals are formed by the floating zone method. Crystals enriched in all 3 stable isotopes of Si have been made: {sup 28}Si (99.92%), {sup 29}Si (91.37%), and {sup 30}Si (88.25%). Concentrations of electrically active impurities (P and B) are as low as mid-10{sup 13} cm{sup -3}. Concentrations of C and O lie below 10{sup 16} and 10{sup 15} cm{sup -3}, respectively.

Applications and theory of electrokinetic enrichment in micro-nanofluidic chips.

Science.gov (United States)

Chen, Xueye; Zhang, Shuai; Zhang, Lei; Yao, Zhen; Chen, Xiaodong; Zheng, Yue; Liu, Yanlin

2017-09-01

This review reports the progress on the recent development of electrokinetic enrichment in micro-nanofluidic chips. The governing equations of electrokinetic enrichment in micro-nanofluidic chips are given. Various enrichment applications including protein analysis, DNA analysis, bacteria analysis, viruses analysis and cell analysis are illustrated and discussed. The advantages and difficulties of each enrichment method are expatiated. This paper will provide a particularly convenient and valuable reference to those who intend to research the electrokinetic enrichment based on micro-nanofluidic chips.

Process for recovering water enriched with deuterium

International Nuclear Information System (INIS)

Mandel, H.

1975-01-01

By the process proposed herewith, enrichment of deuterium in water by cooling water recirculation through series-connection of several cooling ciruits in the form of columns is obtained. With this method, conventional, open-type cooling towers without special installations can be applied, which is an important advantage as compared with a formerly proposed single-stage process with specially designed, complicated cooling towers. Series-connection of the cooling towers is carried out in such a way that the circulating water of a certain cooling circuit, which has a corresponding output value of deuterium enrichment, is conveyed to a succeeding circuit where further enrichment is achieved. The water enriched with deuterium is removed from the last cooling circuit of the series while an amount of fresch water equivalent to the water removed or evaporated altogether is fed to the first circuit of the series. (RB) [de

Including indigestible carbohydrates in the evening meal of healthy subjects improves glucose tolerance, lowers inflammatory markers, and increases satiety after a subsequent standardized breakfast

DEFF Research Database (Denmark)

Nilsson, A.C.; Ostman, E.M.; Holst, Jens Juul

2008-01-01

Low-glycemic index (GI) foods and foods rich in whole grain are associated with reduced risk of type 2 diabetes and cardiovascular disease. We studied the effect of cereal-based bread evening meals (50 g available starch), varying in GI and content of indigestible carbohydrates, on glucose...... tolerance and related variables after a subsequent standardized breakfast in healthy subjects (n = 15). At breakfast, blood was sampled for 3 h for analysis of blood glucose, serum insulin, serum FFA, serum triacylglycerides, plasma glucagon, plasma gastric-inhibitory peptide, plasma glucagon-like peptide-1...... based bread (ordinary, high-amylose- or beta-glucan-rich genotypes) or an evening meal with white wheat flour bread (WWB) enriched with a mixture of barley fiber and resistant starch improved glucose tolerance at the subsequent breakfast compared with unsupplemented WWB (P

75 FR 67086 - Proposed Subsequent Arrangement

Science.gov (United States)

2010-11-01

... concerns the retransfer of 1,470,588.2 kg of U.S.-origin natural uranium hexafluoride (68.00% U), 1,000,000... Areva Resources, will be transferred to Eurodif Production for enrichment and use as fuel in civilian...

75 FR 67087 - Proposed Subsequent Arrangement

Science.gov (United States)

2010-11-01

... concerns the retransfer of 514,705.9 kg of U.S.-origin natural uranium hexafluoride (68.00% U), 350,000 kg... be transferred to URENCO-Gronau for enrichment and use as fuel in civilian nuclear power programs in...

Marine sediment sample pre-processing for macroinvertebrates metabarcoding: mechanical enrichment and homogenization

Directory of Open Access Journals (Sweden)

Eva Aylagas

2016-10-01

Full Text Available Metabarcoding is an accurate and cost-effective technique that allows for simultaneous taxonomic identification of multiple environmental samples. Application of this technique to marine benthic macroinvertebrate biodiversity assessment for biomonitoring purposes requires standardization of laboratory and data analysis procedures. In this context, protocols for creation and sequencing of amplicon libraries and their related bioinformatics analysis have been recently published. However, a standardized protocol describing all previous steps (i.e. processing and manipulation of environmental samples for macroinvertebrate community characterization is lacking. Here, we provide detailed procedures for benthic environmental sample collection, processing, enrichment for macroinvertebrates, homogenization, and subsequent DNA extraction for metabarcoding analysis. Since this is the first protocol of this kind, it should be of use to any researcher in this field, having the potential for improvement.

Community Structure in Methanogenic Enrichments Provides Insight into Syntrophic Interactions in Hydrocarbon-Impacted Environments

DEFF Research Database (Denmark)

Fowler, Jane; Toth, Courtney R. A.; Gieg, Lisa M.

2016-01-01

, but such information has important implications for bioremediation and microbial enhanced energy recovery technologies. Many factors such as changing environmental conditions or substrate variations can influence the composition and biodegradation capabilities of syntrophic microbial communities in hydrocarbon......The methanogenic biodegradation of crude oil involves the conversion of hydrocarbons to methanogenic substrates by syntrophic bacteria and subsequent methane production by methanogens. Assessing the metabolic roles played by various microbial species in syntrophic communities remains a challenge......-impacted environments. In this study, a methanogenic crude oil-degrading enrichment culture was successively transferred onto the single long chain fatty acids palmitate or stearate followed by their parent alkanes, hexadecane or octadecane, respectively, in order to assess the impact of different substrates...

75 FR 21680 - GE-Hitachi Global Laser Enrichment LLC;

Science.gov (United States)

2010-04-26

... Global Laser Enrichment LLC; Establishment of Atomic Safety and Licensing Board Pursuant to delegation by... over the following proceeding: GE-Hitachi Global Laser Enrichment LLC (GLE Commercial Facility) This... application of GE-Hitachi Global Laser Enrichment LLC for a license to possess and use source, byproduct, and...

Safety review and stress test of the uranium enrichment facility Gronau; Compact. Sicherheitsueberpruefung und Stresstest der Urananreicherungsanlage Gronau

Energy Technology Data Exchange (ETDEWEB)

Kleiboemer, Burkhard [URENCO Deutschland GmbH, Gronau (Germany). Ueberwachung

2013-07-01

As a consequence of the earthquake and tsunami in Japan in 2011 and the subsequent catastrophic destruction of the nuclear power plant in Fukushima URENCO has agreed to perform the safety check of the uranium enrichment facility Gronau (UAG) two years earlier than planned. The review was started in May 2011. The contribution deals with the requirements for the safety analysis and the questionnaire for the stress test, the methodology for realization of the safety check and the results of the investigations performed by URENCO and experts of ESK.

Selective adsorption-desorption method for the enrichment of krypton

International Nuclear Information System (INIS)

Yuasa, Y.; Ohta, M.; Watanabe, A.; Tani, A.; Takashima, N.

1975-01-01

Selective adsorption-desorption method has been developed as an effective means of enriching krypton and xenon gases. A seriesof laboratory-scale tests were performed to provide some basic data of the method when applied to off-gas streams of nuclear power plants. For the first step of the enrichment process of the experiments, krypton was adsorbed on solid adsorbents from dilute mixtures with air at temperatures ranging from -50 0 C to -170 0 C. After the complete breakthrough was obtained, the adsorption bed was evacuated at low temperature by a vacuum pump. By combining these two steps krypton was highly enriched on the adsorbents, and the enrichment factor for krypton was calculated as the product of individual enrichment factors of each step. Two types of adsorbents, coconut charcoal and molecular sieves 5A, were used. Experimental results showed that the present method gave the greater enrichment factor than the conventional method which used selective adsorption step only. (U.S.)

Enrichment increases hippocampal neurogenesis independent of blood monocyte-derived microglia presence following high-dose total body irradiation.

Science.gov (United States)

Ruitenberg, Marc J; Wells, Julia; Bartlett, Perry F; Harvey, Alan R; Vukovic, Jana

2017-06-01

Birth of new neurons in the hippocampus persists in the brain of adult mammals and critically underpins optimal learning and memory. The process of adult neurogenesis is significantly reduced following brain irradiation and this correlates with impaired cognitive function. In this study, we aimed to compare the long-term effects of two environmental paradigms (i.e. enriched environment and exercise) on adult neurogenesis following high-dose (10Gy) total body irradiation. When housed in standard (sedentary) conditions, irradiated mice revealed a long-lasting (up to 4 months) deficit in neurogenesis in the granule cell layer of the dentate gyrus, the region that harbors the neurogenic niche. This depressive effect of total body irradiation on adult neurogenesis was partially alleviated by exposure to enriched environment but not voluntary exercise, where mice were single-housed with unlimited access to a running wheel. Exposure to voluntary exercise, but not enriched environment, did lead to significant increases in microglia density in the granule cell layer of the hippocampus; our study shows that these changes result from local microglia proliferation rather than recruitment and infiltration of circulating Cx 3 cr1 +/gfp blood monocytes that subsequently differentiate into microglia-like cells. In summary, latent neural precursor cells remain present in the neurogenic niche of the adult hippocampus up to 8 weeks following high-dose total body irradiation. Environmental enrichment can partially restore the adult neurogenic process in this part of the brain following high-dose irradiation, and this was found to be independent of blood monocyte-derived microglia presence. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

Uranium enrichment. 1980 annual report

International Nuclear Information System (INIS)

1981-05-01

This report contains data and related information on the production of enriched uranium at the gaseous diffusion plants and an update on the construction and project control center for the gas centrifuge plant. Power usage at the gaseous diffusion plants is illustrated. The report contains several glossy color pictures of the plants and processes described. In addition to gaseous diffusion and the centrifuge process, three advanced isotope separation process are now being developed. The business operation of the enrichment plants is described; charts on revenue, balance sheets, and income statements are included

Sulfur isotope separation by anion exchange chromatography: 34 S isotope enrichment

International Nuclear Information System (INIS)

Bendassolli, Jose Albertino; Trivelin, Paulo Cesar O.; Carneiro Junior, Francisco

1995-01-01

The 34 S isotope separation was carried out by isotopic exchange reactions between sulphurous acid in solution and bisulphite anions adsorbed on an ammonium quaternary (Dowex 1 x 8 and Dowex 2 x 8, 100-200 mesh) anion exchange resin packed in columns. Each resin column had 130 cm length and 2.2 cm diameter. The columns were connected in series during displacement of bisulphite bands. For the experiments, a band of bisulphite was fixed to the anion resin, initially in the hydroxyl ion form, and subsequently eluted with 0.2 0.3, 0.4 and 0.6 mol L -1 HCL solution. The hydrochloric acid solution was kept under a nitrogen atmosphere at 245 KPa of pressure, in order to prevent the evolution of gases and also the oxidation of the bisulphite. The experiments showed that the best results were obtained with the elution of bisulphite with 0.2 mol.L -1 HCL, with the Dowex 1 x 8 resin. Enrichments in 34 S of 17.33 atoms% were obtained using Dowex 1 x 8 resin, 0.2 mol.L -1 HCL solution and band displacement of 50 m. Replacing the depleted portion of the band with natural bisulphite, for each 10 m of band displacement, produced 6.79 mmol of sulphurous acid enriched with approximately 17% of 34 S, after 14 m of band dislocation. (author). 7 refs., 1 fig., 2 tabs

Thermal profiles, crystallization behaviors and microstructure of diacylglycerol-enriched palm oil blends with diacylglycerol-enriched palm olein.

Science.gov (United States)

Xu, Yayuan; Zhao, Xiaoqing; Wang, Qiang; Peng, Zhen; Dong, Cao

2016-07-01

To elucidate the possible interaction mechanisms between DAG-enriched oils, this study investigated how mixtures of DAG-enriched palm-based oils influenced the phase behavior, thermal properties, crystallization behaviors and the microstructure in binary fat blends. DAG-enriched palm oil (PO-DAGE) was blended with DAG-enriched palm olein (POL-DAGE) in various percentages (0%, 10%, 30%, 50%, 70%, 90%, 100%). Based on the observation of iso-solid diagram and phase diagram, the binary mixture of PO-DAGE/POL-DAGE showed a better compatibility in comparison with their corresponding original blends. DSC thermal profiles exhibited that the melting and crystallization properties of PO-DAGE/POL-DAGE were distinctively different from corresponding original blends. Crystallization kinetics revealed that PO-DAGE/POL-DAGE blends displayed a rather high crystallization rate and exhibited no spherulitic crystal growth. From the results of polarized light micrographs, PO-DAGE/POL-DAGE blends showed more dense structure with very small needle-like crystals than PO/POL. X-ray diffraction evaluation revealed when POL-DAGE was added in high contents to PO-DAGE, above 30%, β-polymorph dominated, and the mount of β' forms crystals was decreasing. Copyright © 2016 Elsevier Ltd. All rights reserved.

Device and method to enrich and process heavy water

International Nuclear Information System (INIS)

Hammerli, M.M.; Butler, J.P.

1979-01-01

A device to process and enrich heavy water is proposed which is based on a combined electrolysis catalyst exchange system in which a D 2 O enrichment of more than 99.8% is achieved in the end stage. Water partly enriched with D 2 -containing hydrogen gas from an electrolysis cell is brought into contact in a catalyst column. The water is further enriched here with deuterium. It is then fed to the electrolysis cell. Details of the apparatus are closely described. (UWI) [de

Motif enrichment tool.

Science.gov (United States)

Blatti, Charles; Sinha, Saurabh

2014-07-01

The Motif Enrichment Tool (MET) provides an online interface that enables users to find major transcriptional regulators of their gene sets of interest. MET searches the appropriate regulatory region around each gene and identifies which transcription factor DNA-binding specificities (motifs) are statistically overrepresented. Motif enrichment analysis is currently available for many metazoan species including human, mouse, fruit fly, planaria and flowering plants. MET also leverages high-throughput experimental data such as ChIP-seq and DNase-seq from ENCODE and ModENCODE to identify the regulatory targets of a transcription factor with greater precision. The results from MET are produced in real time and are linked to a genome browser for easy follow-up analysis. Use of the web tool is free and open to all, and there is no login requirement. ADDRESS: http://veda.cs.uiuc.edu/MET/. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

The case for enrichment of uranium in Australia

International Nuclear Information System (INIS)

George, D.W.

1981-01-01

Information is presented on the number of nuclear power plants in operation and under construction and on the extent of the use of uranium. The case for enrichment of uranium in Australia is then considered in detail and the status of feasbility studies being carried out is discussed. Arguments to support an enrichment industry include: the need for additional enrichment capacity; added value; potential profitability; increased employment and industrial opportunities; and retention of depleted uranium

Optimal pin enrichment distributions in nuclear reactor fuel bundles

International Nuclear Information System (INIS)

Lim, E.Y.

1976-01-01

A methodology has been developed to determine the fuel pin enrichment distribution that yields the best approximation to a prescribed power distribution in nuclear reactor fuel bundles. The problem is formulated as an optimization problem in which the optimal pin enrichments minimize the sum of squared deviations between the actual and prescribed fuel pin powers. A constant average enrichment constraint is imposed to ensure that a suitable value of reactivity is present in the bundle. When constraints are added that limit the fuel pins to a few enrichment types, one must determine not only the optimal values of the enrichment types but also the optimal distribution of the enrichment types amongst the pins. A matrix of boolean variables is used to describe the assignment of enrichment types to the pins. This nonlinear mixed integer programming problem may be rigorously solved with either exhaustive enumeration or branch and bound methods using a modification of the algorithm from the continuous problem as a suboptimization. Unfortunately these methods are extremely cumbersome and computationally overwhelming. Solutions which require only a moderate computational effort are obtained by assuming that the fuel pin enrichments in this problem are ordered as in the solution to the continuous problem. Under this assumption search schemes using either exhaustive enumeration or branch and bound become computationally attractive. An adaptation of the Hooke--Jeeves pattern search technique is shown to be especially efficient

Functional properties of pasta enriched with variable cereal brans.

Science.gov (United States)

Kaur, Gurkirat; Sharma, Savita; Nagi, H P S; Dar, Basharat N

2012-08-01

To explore the potentiality of cereal brans for preparation of fiber enriched pasta, various cereal brans (Wheat, Rice, Barley and Oat) were added at 0, 5, 10, 15, 20 and 25 per cent to durum wheat semolina. The effect of cereal bran enrichment on the colour, cooking, sensory quality and shelf life of enriched pasta was assessed at ambient temperature. Pasta prepared with added fiber at 25 per cent level had the highest protein and dietary fiber content as compared to control. Enrichment with variable fiber sources improved the brightness of pasta, as colour of pasta enhanced significantly. Addition of cereal brans resulted an increase in the water absorption and cooking losses of pasta. This effect was dependent on the level and type of cereal brans. Significant correlation (r = 0.80) was obtained between water absorption and volume expansion in all types of bran enriched pasta. At 25 per cent level of supplementation, maximum solids were leached into cooking water. Bran enriched pasta required less cooking time for complete gelatinization of starch. Increasing level of cereal brans had significantly affected the overall acceptability of enriched pasta. Cooking quality of pasta remained constant during storage. Non significant effect of storage was found on water activity, free fatty acids. Enriched pasta (15 per cent level of wheat, rice and oat bran and 10 per cent barley bran) was highly acceptable upto 4 months of storage with respect to quality.

Synthesis of fertilizers nitrogen and 15N-enriched. Pt. I. Production of enriched 15N-anhydrous ammonia

International Nuclear Information System (INIS)

Bendassolli, J.A.; Mortatti, J.; Trivelin, P.C.O.; Victoria, R.L.

1988-01-01

The results of 15 N-anhydrous ammonia production through reaction between 15 N-enriched ammonium sulphate and sodium hidroxide are reported. Influence of the reaction temperature, carrier gas flow, reaction time and mass of ammonium sulphate on the production of anhydrous ammonia were studied. Analyses for the cost of production of 5% atoms in 15 N-enriched anhydrous ammonia were made. (M.A.C.) [pt

Isotopically enriched structural materials in nuclear devices

Energy Technology Data Exchange (ETDEWEB)

Morgan, L.W.G., E-mail: Lee.Morgan@ccfe.ac.uk [CCFE, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Shimwell, J. [CCFE, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom); Department of Physics and Astronomy, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Gilbert, M.R. [CCFE, Culham Science Centre, Abingdon, Oxfordshire OX14 3DB (United Kingdom)

2015-01-15

Highlights: • C-B analysis of isotopic enrichment of structural materials is presented. • Some, previously, prohibited elements could be used as alloying elements in LAM's. • Adding enriched molybdenum and nickel, to EUROFER, could increase availability. • Isotope enrichment for EUROFER could be cost-effective. • Isotopically enriching copper, in CuCrZr, can reduce helium production by 50%. - Abstract: A large number of materials exist which have been labeled as low activation structural materials (LAM). Most often, these materials have been designed in order to substitute-out or completely remove elements that become activated and contribute significantly to shut-down activity after being irradiated by neutrons in a reactor environment. To date, one of the fundamental principles from which LAMs have been developed is that natural elemental compositions are the building blocks of LAMs. Thus, elements such as Co, Al, Ni, Mo, Nb, N and Cu that produce long-lived decay products are significantly reduced or removed from the LAM composition. These elements have an important part to play in the composition of steels and the removal/substitution can have a negative impact on materials properties such as yield stress and fracture toughness. This paper looks in more detail at whether using isotopic selection of the more mechanically desirable, but prohibited due to activation, elements can improve matters. In particular, this paper focuses on the activation of Eurofer. Carefully chosen isotopically enriched elements, which are normally considered to be on the prohibited element list, are added to EUROFER steel as potential alloying elements. The EUROFER activation results show that some prohibited elements can be used as alloying elements in LAM steels, providing the selected isotopes do not have a significant impact on waste disposal rating or shut-down dose. The economic implications of isotopically enriching elements and the potential implications for

Principles and techniques of uranium enrichment

International Nuclear Information System (INIS)

Frejacques, Claude; Mezin, Michel

1975-01-01

The main separation processes already used industrially or likely to be used before the end of century (gas diffusion, ultracentrifugation, laser, the nozzle process, a process developed in South Africa) are presented. Some data on the costs of the enrichment are clarified. The main characteristics of the enrichment market in which the Eurodif plant is called upon, on the expiration of five years, to take a foremost place are reported [fr

A short-term intervention trial with selenate, selenium-enriched yeast and selenium-enriched milk: effects on oxidative defence regulation

DEFF Research Database (Denmark)

Ravn-Haren, Gitte; Bugel, Susanne; Krath, Britta

2008-01-01

-enriched yeast or Se-enriched milk. We found no effect on plasma lipid resistance to oxidation, total cholesterol, TAG, HDL- and LDL-cholesterol, GPX, glutathione reductase (GR) and glutathione S-transferase (GST) activities measured in erythrocytes, GPX and GR activities determined in plasma, or GR and GST...

Enriched uranium cycles in pressurized heavy water reactors

International Nuclear Information System (INIS)

Mazzola, A.

1994-01-01

A study was made on the substitution of natural uranium with enriched and on plutonium recycle in unmodified PHWRs (pressure vessel reactor). Results clearly show the usefulness of enriched fuel utilisation for both uranium ore consumption (savings of 30% around 1.3% enrichment) and decreasing fuel cycle coasts. This is also due to a better plutonium exploitation during the cycle. On the other hand plutonium recycle in these reactors via MOX-type fuel appears economically unfavourable under any condition

The Passive Neutron Enrichment Meter for Uranium Cylinder Assay

Energy Technology Data Exchange (ETDEWEB)

Miller, Karen A.; Menlove, Howard O.; Swinhoe, Martyn T.; Marlow, Johanna B. [Safeguards Science and Technology Group (N-1), Los Alamos National Laboratory, Los Alamos (United States)

2011-12-15

As fuel cycle technology becomes more prevalent around the world, international safeguards have become increasingly important in verifying that nuclear materials have not been diverted. Uranium enrichment technology is a critical pathway to nuclear weapons development, making safeguards of enrichment facilities especially important. Independently-verifiable material accountancy is a fundamental measure in detecting diversion of nuclear materials. This paper is about a new instrument for uranium cylinder assay for enrichment plant safeguards called the Passive Neutron Enrichment Meter (PNEM). The measurement objective is to simultaneously verify uranium mass and enrichment in Uf6 cylinders. It can be used with feed, product, and tails cylinders. Here, we consider the enrichment range up to 5% {sup 235}U. The concept is to use the Doubles-to-Singles count rate to give a measure of the {sup 235}U enrichment and the Singles count rate to provide a measure of the total uranium mass. The cadmium ratio is an additional signature for the enrichment that is especially useful for feed and tails cylinders. PNEM is a {sup 3}He-based system that consists of two portable detector pods. Uranium enrichment in UF{sub 6} cylinders is typically determined using a gamma-ray-based method that only samples a tiny volume of the cylinder's content and requires knowledge of the cylinder wall thickness. The PNEM approach has several advantages over gamma-ray-based methods including a deeper penetration depth into the cylinder, meaning it can be used with heterogeneous isotopic mixtures of UF{sub 6}. In this paper, we describe a Monte Carlo modelling study where we have examined the sensitivity of the system to systematic uncertainties such as the distribution of UF{sub 6} within the cylinder. We also compare characterization measurements of the PNEM prototype to the expected measurements calculated with Monte Carlo simulations.

Novel meat-enriched foods for older consumers.

Science.gov (United States)

Farouk, Mustafa M; Yoo, Michelle J Y; Hamid, Nazimah S A; Staincliffe, Maryann; Davies, Briar; Knowles, Scott O

2018-02-01

Red meat enriched versions of bread, spaghetti, yoghurt, ice cream and chocolate were prototyped and assessed for some of their physical, chemical and microbiological properties, as well as sensory appeal. The protein content of the products were significantly increased and their colour went darker with meat enrichment (pice cream meltability and yoghurt apparent viscosity decreased with meat enrichment (pice cream and spaghetti were not affected (p>0.05) but that of non-flavoured ice cream and yoghurt went down (pindustry stretch its established business models, and encouraging further development of novel food choices for elderly and other groups of consumers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Uranium enrichment management review. Final report

International Nuclear Information System (INIS)

Ellett, J.D.; Rieke, W.B.; Simpson, J.W.; Sullivan, P.E.

1980-01-01

The uranium enrichment enterprise of the US Department of Energy (DOE) provides enriched nuclear fuel for private and government utilities domestically and abroad. The enterprise, in effect, provides a commercial service and represents a signficant business operation within the US government: more than $1 billion in revenues annually and future capital expenditures estimated at several billions of dollars. As a result, in May 1980, the Assistant Secretary for Resource Applications within DOE requested that a group of experienced business executives be assembled to review the operation, financing, and management of the uranium enrichment enterprise as a basis for advising the Secretary of Energy. The review group was specifically asked to focus on the management activities to which sound business practices could be applied. The group developed findings and recommendations in six areas: management of operations and construction; long-range planning; marketing of enrichment services; financial management; research and development; and general management. The chapters of this report present first the management review group's recommendations in the six areas evaluated and then the findings and issues in each area. An appendix provides the group's calendar of meetings. A list of major reference sources used in the course of the study is also included. 12 references

Measurement of the enrichment of uranium-hexafluoride gas in product pipes in the centrifuge enrichment plant at Almelo

International Nuclear Information System (INIS)

Packer, T.W.; Lees, E.W.; Aaldijk, J.K.; Harry, R.J.S.

1987-09-01

One of the objectives of safeguarding centrifuge enrichment plants is to apply non-destructive measurements inside the cascade area to confirm that the enrichment level is in the low enriched uranium range. Research in the UK and USA has developed a NDA instrument which can confirm the presence of low enriched uranium on a rapid go/no go basis in cascade header pipework of their centrifuge enrichment plants. The instrument is based on a gamma spectroscopic measurement coupled with an X-ray fluorescence analysis. This report gives the results of measurements carried out at Almelo by the UKAEA Harwell, ECN Petten and KFA Juelich to determine if these techniques could be employed at Almelo and Gronau. The energy dispersive X-ray fluorescence analysis has been applied to determine the total mass of uranium in the gas phase, and the deposit correction technique and the two geometry technique have been applied at Almelo to correct the measured gamma intensities for those emitted by the deposit. After an executive summary the report discusses the principles of the two correction methods. A short description of the equipment precedes the presentation of the results of the measurements and the discussion. After the conclusions the report contains two appendices which contain the derivation of the formulae for the deposit correction technique and a discussion of the systematic errors of this technique. 8 figs.; 11 refs.; 6 tables

Assuaging Nuclear Energy Risks: The Angarsk International Uranium Enrichment Center

International Nuclear Information System (INIS)

Myers, Astasia

2011-01-01

The recent nuclear renaissance has motivated many countries, especially developing nations, to plan and build nuclear power reactors. However, domestic low enriched uranium demands may trigger nations to construct indigenous enrichment facilities, which could be redirected to fabricate high enriched uranium for nuclear weapons. The potential advantages of establishing multinational uranium enrichment sites are numerous including increased low enrichment uranium access with decreased nuclear proliferation risks. While multinational nuclear initiatives have been discussed, Russia is the first nation to actualize this concept with their Angarsk International Uranium Enrichment Center (IUEC). This paper provides an overview of the historical and modern context of the multinational nuclear fuel cycle as well as the evolution of Russia's IUEC, which exemplifies how international fuel cycle cooperation is an alternative to domestic facilities.

Energy consumption of chemical uranium enrichment

International Nuclear Information System (INIS)

Miyake, T.; Takeda, K.; Obanawa, H.

1987-01-01

A quantitative study of chemical separation energy for enriching uranium-235 by the redox chromatography was conducted. Isotope exchange reactions between U 4+ -UO 2 2+ ions in the enrichment column are maintained by the redox reactions. The chemical separation energy is ultimately supplied by hydrogen and oxygen gas for regenerating redox agents. The redox energy for the isotope separation is theoretically predicted as a function of the dynamic enrichment factor observed in the chromatographic development of uranium adsorption band. Thermodynamic treatments of the equilibrium reactions implies and inverse redox reaction which can be enhanced by the chemical potential of the ion-exchange reaction of oxidant. Experimental results showed 30 to 90% recovery of the redox energy by the inverse reaction. These results will devise a simplified redox chromatography process where a number of columns in one module is reduced

An Enriching Community.

Science.gov (United States)

Holland, Nancy A.; Burroughs, Jean

2001-01-01

Successful school-community partnerships in Volusia (Florida) Public Schools are the results of marketing creatively, meeting community members' needs, and bringing the right people together. The 3-year old program now offers students of all ages an expanding list of enrichment classes on many subjects for a nominal fee. (MLH)

Is there a potential win for companies when women enrich their role of workers through the enrichement of their family lives?

OpenAIRE

Oliveira, Inês Martins

2015-01-01

While the work-family relation conflict literature has received much attention, there is a lack of empirical evidence towards work-family positive relation. Furthermore, there is a lack of understanding and recognition of possible benefits obtained by skills’ development during maternity. This study concludes that a family-work relation has a positive outcome, namely the enrichment. It was evident that there is a potential win when women enrich their role as workers through the enrichment of ...

Uranium-enriched granites in Sweden

International Nuclear Information System (INIS)

Wilson, M.R.; Aakerblom, G.

1980-01-01

Granites with uranium contents higher than normal occur in a variety of geological settings in the Swedish Precambrian, and represent a variety of granite types and ages. They may have been generated by the anatexis of continental crust or processes occurring at a much greater depth. They commonly show enrichment in F, Sn, W and/or Mo. Only in one case is an important uranium mineralization thought to be directly related to a uranium-enriched granite, while the majority of epigenetic uranium mineralizations with economic potential are related to hydrothermal processes in areas where the bedrock is regionally uranium-enhanced. (author)

Uranium enriched granites in Sweden

International Nuclear Information System (INIS)

Wilson, M.R.; Aakerblom, G.

1980-01-01

Granites with uranium contents higher than normal occur in a variety of geological settings in the Swedish Precambrian, and represent a variety of granite types and ages. They may have been generated by (1) the anatexis of continental crust (2) processes occurring at a much greater depth. They commonly show enrichement in F, Sn, W and/or Mo. Only in one case is an important uranium mineralization thought to be directly related to a uranium-enriched granite, while the majority of epigenetic uranium mineralizations with economic potential are related to hydrothermal processes in areas where the bedrock is regionally uranium-enhanced. (Authors)

Environmental Enrichment for Broiler Breeders: An Undeveloped Field

DEFF Research Database (Denmark)

Riber, Anja Brinch; Jong, Ingrid de; van de Werd, Heleen A.

2017-01-01

Welfare problems, such as hunger, frustration, aggression, and abnormal sexual behavior, are commonly found in broiler breeder production. To prevent or reduce these welfare problems, it has been suggested to provide stimulating enriched environments. We review the effect of the different types...... of environmental enrichment for broiler breeders, which have been described in the scientific literature, on behavior and welfare. Environmental enrichment is defined as an improvement of the environment of captive animals, which increases the behavioral opportunities of the animal and leads to improvements...... in biological function. This definition has been broadened to include practical and economic aspects as any enrichment strategy that adversely affects the health of animals (e.g., environmental hygiene), or that has too many economic or practical constraints will never be implemented on commercial farms...

The uranium enrichment industry and the SILEX process

International Nuclear Information System (INIS)

Goldsworthy, M.

1999-01-01

Silex Systems Limited has been developing a new laser isotope separation process since 1992. The principle application of the SILEX Technology is Uranium Enrichment, the key step in the production of fuel for nuclear power plants. The Uranium Enrichment industry, today worth ∼ US$3.5 Billion p.a., is dominated by four major players, the largest being USEC with almost 40% of the market. In 1996, an agreement was signed between Silex and USEC to develop SILEX Technology for potential application to Uranium Enrichment. The SILEX process is a low cost, energy efficient scheme which may provide significant commercial advantage over current technology and competing laser processes. Silex is also investigating possible application to the enrichment of Silicon, Carbon and other materials. Significant markets may develop for such materials, particularly in the semiconductor industry

The assisting system for uranium enrichment plant operation

International Nuclear Information System (INIS)

Nakazawa, Hiroaki; Yamamoto, Fumio

1990-01-01

We have been developing an operation assisting system, partially supported by AI system, for uranium enrichment plant. The AI system is a proto-type system aiming a final one which can be applied to any future large uranium enrichment plant and also not only to specific operational area but also to complex and multi-phenomenon operational area. An existing AI system, for example facility diagnostic system that utilizes the result of CCT analysis as knowledge base, has weakness in flexibility and potentiality. To build AI system, we have developed the most suitable knowledge representations using deep knowledge for each facility or operation of uranium enrichment plant. This paper describes our AI proto-type system adopting several knowledge representations that can represent an uranium enrichment plant's operation with deep knowledge. (author)

Uranium enrichment techniques

International Nuclear Information System (INIS)

Hamdoun, N.A.

2007-01-01

This article includes an introduction about the isotopes of natural uranium, their existence and the difficulty of the separation between them. Then it goes to the details of a number of methods used to enrich uranium: Gaseous Diffusion method, Electromagnetic method, Jet method, Centrifugal method, Chemical method, Laser method and Plasma method.

Enriching the Catalog

Science.gov (United States)

Tennant, Roy

2004-01-01

After decades of costly and time-consuming effort, nearly all libraries have completed the retrospective conversion of their card catalogs to electronic form. However, bibliographic systems still are really not much more than card catalogs on wheels. Enriched content that Amazon.com takes for granted--such as digitized tables of contents, cover…

Tandem Rh-Catalyzed Oxidative C-H Olefination and Cyclization of Enantiomerically Enriched Benzo-1,3-Sulfamidates: Stereoselective Synthesis of trans-1,3-Disubstituted Isoindolines.

Science.gov (United States)

Achary, Raghavendra; Jung, In-A; Lee, Hyeon-Kyu

2018-04-06

A tandem process, involving Rh(III)-catalyzed oxidative C-H olefination of enantiomerically enriched 4-aryl-benzo-1,3-sulfamidates and subsequent intramolecular aza-Michael cyclization has been developed. The reaction produces trans-benzosulfamidate-fused-1,3-disubstituted isoindolines as major products, in which the configurational integrity of the stereogenic center in the starting material is preserved. Further transformations of the benzosulfamidate-fused-1,3-disubstituted isoindolines are described.

Optimal set of selected uranium enrichments that minimizes blending consequences

International Nuclear Information System (INIS)

Nachlas, J.A.; Kurstedt, H.A. Jr.; Lobber, J.S. Jr.

1977-01-01

Identities, quantities, and costs associated with producing a set of selected enrichments and blending them to provide fuel for existing reactors are investigated using an optimization model constructed with appropriate constraints. Selected enrichments are required for either nuclear reactor fuel standardization or potential uranium enrichment alternatives such as the gas centrifuge. Using a mixed-integer linear program, the model minimizes present worth costs for a 39-product-enrichment reference case. For four ingredients, the marginal blending cost is only 0.18% of the total direct production cost. Natural uranium is not an optimal blending ingredient. Optimal values reappear in most sets of ingredient enrichments

Tritium enrichment of environmental waters by electrolysis: Development of cathodes exhibiting high isotopic separation and precise measurement of tritium enrichment factors

International Nuclear Information System (INIS)

Taylor, C.B.

1976-01-01

Equations are developed for the estimation of tritium enrichment in batch, continuous feed and periodic addition electrolysis cells. Optimum enrichment and minimum variability is obtained using developed cathode surfaces which catalyse the separation of tritium, as exhibited by the results of experiments using mild steel cathodes with NaOH electrolyte. The equations and various simple refinements of technique are applied to the determination of tritium enrichment factors by the spike cell method: for batch cells the standard errors are less than 1%. (author)

Marché européen des margarines et des matières grasses à tartiner

Directory of Open Access Journals (Sweden)

Herreman Inneke

2005-09-01

Full Text Available IMACE, the International Margarine Association of the Countries of Europe represents 21 national associations of the margarine industry. While in 2003 the World Production increased to 10.1 Mt (9.3 Mt in 1998, the production of the European countries of 15 was 1.9 Mt (2.3 Mt in 1998. In 2003 the most important European producing countries are Germany (446,000 t, the United Kingdom (322,000 t, Belgium (268,000 t, the Netherlands (289,000 t and Poland (510,000 t. The changes in food habits involved a decline of consumption. But the sector has invested a lot in optimizing the composition of its products, with a special attention for unsaturated fatty acids. European Union food legislation that has a particular impact on the margarine industry are the proposed EU Claims regulation, the proposed EU harmonization of vitamins and minerals, the EU directives on full ingredient labelling and on nutrition labelling. But the industry also actively pursues a road of self-regulation i.e. IMACE Code of Practice on Nutrition Claims, IMACE Code of Practice on Addition of Vitamins, IMACE Code of Practice on TFA. Several scientific publications recognize the margarine industry’s efforts in reducing TFA and underline that they are known as a determinant factor in the overall reduction of TFA in food products.

Uranium enrichment : global view and Brazilian perspectives

International Nuclear Information System (INIS)

Zouain, D.M.; Sakamoto, L.H.

1981-12-01

A global view of isotope enrichment involving a general description of process (technical-economical aspects and policy) and status in developing countries is done. An enrichment demand in function of the Brazilian Nuclear Program is evaluated, analyzing a probable market and a low market. The perspectives to attend this demand, are studied. (E.G.) [pt

The gas centrifuge, uranium enrichment and nuclear proliferation

International Nuclear Information System (INIS)

Chapman, A.

1988-01-01

The author considers the consequences for controlling nuclear proliferation of the emergence of the gas centrifuge method for enriching uranium and succeeds in the difficult and delicate task of saying enough about gas centrifuge techniques for readers to judge, what may be involved in fully embracing gas centrifuge enrichment within the constraints of an anti-proliferation strategy, whilst at the same time saying nothing that could be construed as encouraging an interest in the gas centrifuge route to highly enriched uranium where none had before existed. (author)

The evolution of the enriched uranium markets

International Nuclear Information System (INIS)

Arnaiz, J.; Moleres, C.; Tarin, F.

2004-01-01

This paper deals with the evolution of the enriched uranium component markets (uranium concentrates, conversion and enrichment), starting with the situation of historically low prices that occurred during 2000. The situation that has been reached as on December 2003, when the concentrates and conversion markets were 44% and 70% (current US$) respectively, and the enrichment prices 30%, higher, is analysed. Finally, the negative impact of the 90's depressed prices, due to abundant alternative sources of uranium components, on the primary production of all three components and, as a conclusion, the impact of the new situation on the transport logistics, and the need of appropriate economic conditions to make the future primary production sustainable, is commented. (Author)

Combination of Cobe AutoPBSC and Gambro Elutra as a platform for monocyte enrichment in dendritic cell (DC) therapy: clinical study.

Science.gov (United States)

Chen, Ying; Hoecker, Paul; Zeng, Jia; Dettke, Markus

2008-01-01

Monocytes are a common source for generating dendritic cells (DCs). The aim of the present study was to evaluate the efficiency of a platform for monocyte collection and enrichment in a clinical setting. The platform was based on the combination of two semiautomated devices; the Cobe Spectra Auto PBSC for mononuclear cells (MNC) collection followed by counterflow elutriation for monocyte enrichment (Gambro BCT Elutra). Twenty-four patients with various types of epithelial cancer participated in the study. MNC collections were first performed as large volume leukapheresis (LVL). Subsequently, MNC products were processed with an elutriation system for monocyte isolation. LVL resulted in the collection of MNC at a median of 8.1 x 10(9) cells, containing of 31.4% monocytes. A similar efficacy was also shown in patients with lower peripheral blood counts. Elutriation of the MNC product with the Cobe Elutra device resulted in the enrichment of monocytes at a median of 2.7 x 10(9) cells, with a recovery of 80.2% and a purity of 90.7%. These monocytes were then successfully developed into DCs for clinical therapy after in vitro manipulation. These data suggest that the combination of the Cobe Spectra Auto PBSC and the Gambro BCT Elutra is an effective platform for monocyte enrichment in clinical practice according to GCP standards and GMP guidelines, and can be easily implemented in the clinical routine under current DC protocols. Copyright 2008 Wiley-Liss, Inc.

Experience with environmental sampling at gas centrifuge enrichment plants

International Nuclear Information System (INIS)

Ekenstam, G. af; Bush, W.; Janov, J.; Kuhn, E.; Ryjinski, M.

2001-01-01

Environmental sampling has been used routinely by the IAEA since 1996 after the IAEA Board of Governors approved it in March 1995 as a new technique to strengthen safeguards and improve efficiency. In enrichment plants it is used to confirm that there has been no production of highly enriched uranium (HEU), or production of uranium at above the declared enrichment. The use of environmental sampling is based on the assumption that every process, no matter how leak tight, will release small amounts of process material to the environment. Even though these releases of nuclear material are extremely small in gas centrifuge enrichment plants, and well below levels of concern from a health physics and safety standpoint, they are detectable and their analysis provides an indication of the enrichment of the material that has been processed in the plant. The environmental samples at enrichment plants are collected by swiping selected areas of the plant with squares of cotton cloth (10x10 cm) from sampling kits prepared in ultra clean condition. The squares of cotton cloth sealed in plastic bags are sent for analysis to the Network Analytical Laboratories. The analysis includes the measurement of the uranium isotopic composition in uranium-containing particles by Thermal lonization Mass Spectroscopy (TIMS) or Secondary ION Mass Spectroscopy (SIMS). Since the implementation of environmental sampling, swipes have been collected from 240 sampling points at three gas centrifuge plants of URENCO, which have a total throughput of more than 8,000 tonnes of uranium per year. The particle analysis results generally reflected the known operational history of the plants and confirmed that they had only been operated to produce uranium with enrichment less than 5% 235 U. The information about the content of the minor isotopes 234 U and 236 U also indicates that depleted and recycled uranium were sometimes used as feed materials in some plants. An example is given of the TIMS particle

Preparation of isotopically enriched mercury sulphide targets

Energy Technology Data Exchange (ETDEWEB)

Szerypo, J.; Friebel, H.U.; Frischke, D.; Grossman, R.; Maier, H.J. [Dept. fuer Physik, Univ. Muenchen (LMU) (Germany); Maier-Leibnitz-Lab. (MLL), Garching (Germany)

2007-07-01

The primary difficulty in performing nuclear reactions on mercury is to obtain a suitable target. The primary difficulty in performing nuclear reactions on mercury is to obtain a suitable target. The utilization of amalgam targets has been reported in early publications. These targets, however, were lacking homogeneity and in-beam stability. A thorough investigation of literature shows, that HgS, because of its comparatively high chemical and mechanical stability, is one of the more adequate Hg compounds for accelerator target applications. In this presentation we describe the production of HgS targets consisting of an enriched Hg isotope and S of natural isotopic abundance, starting up from HgO. Following the outline given in [3], in this special case HgS can be prepared by dissolving HgO in diluted HNO{sub 3} and subsequent precipitation of the black HgS modification with gaseous H{sub 2}S. Last step of the target production procedure is evaporation-condensation of HgS in vacuum. In the present case, HgS layers of 500 {mu}g/cm{sup 2} on a backing carbon foil of 26 {mu}g/cm{sup 2} with a protective carbon layer of about 20 {mu}g/cm{sup 2} thickness on top of the HgS layer were produced. (orig.)

Enrichment measurement in TRIGA type fuels

International Nuclear Information System (INIS)

Aguilar H, F.; Mazon R, R.

2001-05-01

The Department of Energy of the United States of North America, through the program 'Idaho Operations Nuclear Spent Fuel Program' of the Idaho National Engineering and Environmental Laboratory (INEEL), in Idaho Falls; Idaho USA, hires to Global Technologies Inc. (GTI) to develop a prototype device of detection enrichment uranium (DEU Detection of Enrichment of Uranium) to determine quantitatively the enrichment in remainder U-235 in a TRIGA fuel element at the end of it useful life. The characteristics of the prototype developed by GTI are the following ones: It allows to carry out no-destructive measurements of TRIGA type fuel. Easily transportable due to that reduced of it size. The determination of the enrichment (in grams of U-235) it is obtained with a precision of 5%. The National Institute of Nuclear Research (ININ), in its facilities of the Nuclear Center of Mexico, it has TRIGA type fuel of high and low enrichment (standard and FLIP) fresh and with burnt, it also has the infrastructure (hot cells, armor-plating of transport, etc) and qualified personnel to carry out the necessary maneuvers to prove the operation of the DEU prototype. For this its would be used standard type fuel elements and FLIP, so much fresh as with certain burnt one. In the case of the fresh fuels the measurement doesn't represent any risk, the fuels before and after the measurement its don't contain a quantity of fission products that its represent a radiological risk in its manipulation; but in the case of the fuels with burnt the handling of the same ones represents an important radiological risk reason why for its manipulation it was used the transport armor-plating and the hot cells. (Author)

DOE hands over uranium enrichment duties to government corporation

International Nuclear Information System (INIS)

Simpson, J.

1993-01-01

In an effort to renew the United States' competitiveness in the world market for uranium enrichment services, the Department of Energy (DOE) is turning over control of its Paducah, KY, and Portsmouth, OH, enrichment facilities to a for-profit organization, the United States Enrichment Corp. (USEC), which was created by last year's Energy Policy Act. William H. Timbers, Jr., a former investment banker who was appointed acting CEO in March, said the Act's mandate will mean more competitive prices for enriched reactor fuel and greater responsiveness to utility customers. As a government corporation, USEC, with current annual revenues estimated at $1.5 billion, will no longer be part of the federal budget appropriations process, but will use business management techniques, set market-based prices for enriched uranium, and pay annual dividends to the US Treasury-its sole stockholder-from earnings. The goal is to finish privatizing the corporation within two years, and to sell its stock to investors for an estimated $1 to $3 billion. USEC's success will depend in part on developing short- and long-term marketing plants to help stanch the flow of enriched-uranium customers to foreign suppliers. (DOE already has received notice from a number of US utilities that they want to be let out of their long-term enrichment contracts as they expire over the next several years).USEC's plans likely will include exploring new joint ventures with other businesses in the nuclear fuel cycle-such as suppliers, fabricators, and converters-and offering a broader range of enrichment services than DOE provided. The corporation will have to be responsive to utilities on an individual basis

GSL-enriched membrane microdomains in innate immune responses.

Science.gov (United States)

Nakayama, Hitoshi; Ogawa, Hideoki; Takamori, Kenji; Iwabuchi, Kazuhisa

2013-06-01

Many pathogens target glycosphingolipids (GSLs), which, together with cholesterol, GPI-anchored proteins, and various signaling molecules, cluster on host cell membranes to form GSL-enriched membrane microdomains (lipid rafts). These GSL-enriched membrane microdomains may therefore be involved in host-pathogen interactions. Innate immune responses are triggered by the association of pathogens with phagocytes, such as neutrophils, macrophages and dendritic cells. Phagocytes express a diverse array of pattern-recognition receptors (PRRs), which sense invading microorganisms and trigger pathogen-specific signaling. PRRs can recognize highly conserved pathogen-associated molecular patterns expressed on microorganisms. The GSL lactosylceramide (LacCer, CDw17), which binds to various microorganisms, including Candida albicans, is expressed predominantly on the plasma membranes of human mature neutrophils and forms membrane microdomains together with the Src family tyrosine kinase Lyn. These LacCer-enriched membrane microdomains can mediate superoxide generation, migration, and phagocytosis, indicating that LacCer functions as a PRR in innate immunity. Moreover, the interactions of GSL-enriched membrane microdomains with membrane proteins, such as growth factor receptors, are important in mediating the physiological properties of these proteins. Similarly, we recently found that interactions between LacCer-enriched membrane microdomains and CD11b/CD18 (Mac-1, CR3, or αMβ2-integrin) are significant for neutrophil phagocytosis of non-opsonized microorganisms. This review describes the functional role of LacCer-enriched membrane microdomains and their interactions with CD11b/CD18.

Evaluation of economical at a uranium enrichment demonstration plant

International Nuclear Information System (INIS)

Sugitsue, Noritake

2001-01-01

In this report, the economy of technical achievement apply in the uranium enrichment demonstration plant is evaluated. From the evaluation, it can be concluded that the expected purpose was achieved because there was a definite economic prospect to commercial plant. The benefit analysis of thirteen years operation of the uranium enrichment demonstration plant also provides a financial aspect of the uranium enrichment business. Therefore, the performance, price and reliability of the centrifuge is an important factor in the uranium enrichment business. And the continuous development of a centrifuge while considering balance with the development cost is necessary for the business in the future. (author)

Enriching Orphans’ Potentials through Interpersonal and Intrapersonal Intelligence Enrichment Activities

Directory of Open Access Journals (Sweden)

Nurulwahida Hj Azid

2016-01-01

Full Text Available Orphans are considered a minority and they should be given a greater emphasis so that they do not feel left out and can build their own lives without a sense of humility. This does not mean that the orphans should be pampered instead they should be given the confidence and motivation to strive for success in later life. Humility among orphans can be associated with interpersonal and intrapersonal intelligences. This study aims to evaluate the impact of problem-solving activity treatment based on the interpersonal and intrapersonal intelligences. 46 students from two orphanages were involved as the treatment group. The research design used was a one-group pretest-posttest design applied through a combination of quantitative and qualitative approaches. Enrichment activities that provided interpersonal and intrapersonal skills as evidenced in this study should be carried out regularly at orphanages. Our study has proven that orphans‟ rights to learn cannot be neglected and „no child left behind „policy needs to be carried through by everybody involved with orphans‟ well-being. Teachers and carers need to be trained to use these enrichment activities at their orphanages to help maximize the orphans‟ potentials.

Data analysis for neutron monitoring in an enrichment facility

International Nuclear Information System (INIS)

Markin, J.T.; Stewart, J.E.; Goldman, A.S.

1982-01-01

Area monitoring of neutron radiation to detect high-enriched uranium production is a potential strategy for inspector verification of operations in the cascade area of a centrifuge enrichment facility. This paper discusses the application of statistical filtering and hypothesis testing procedures to experimental data taken in an enrichment facility. The results demonstrate that these data analysis methods can enhance detection of facility misoperation by neutron monitoring

Enriching stable isotopes: Alternative use for Urenco technology

International Nuclear Information System (INIS)

Rakhorst, H.; de Jong, P.G.T.; Dawson, P.D.

1996-01-01

The International Urenco Group utilizes a technologically advanced centrifuge process to enrich uranium in the fissionable isotope 235 U. The group operates plants in the United Kingdom, the Netherlands, and Germany and currently holds a 10% share of the multibillion dollar world enrichment market. In the early 1990s, Urenco embarked on a strategy of building on the company's uniquely advanced centrifuge process and laser isotope separation (LIS) experience to enrich nonradioactive isotopes colloquially known as stable isotopes. This paper summarizes the present status of Urenco's stable isotopes business

The Enriched Effect Calculus: Syntax and Semantics

DEFF Research Database (Denmark)

Møgelberg, Rasmus Ejlers; Simpson, Alex; Egger, Jeff

2014-01-01

This article introduces the enriched effect calculus, which extends established type theories for computational effects with primitives from linear logic. The new calculus provides a formalism for expressing linear aspects of computational effects; e.g. the linear usage of imperative features....... The second half of the article investigates models for the enriched effect calculus, based on enriched category theory. We give several examples of such models, relating them to models of standard effect calculi (such as those based on monads), and to models of intuitionistic linear logic. We also prove...

Study on behaviors and performances of universal N-glycopeptide enrichment methods.

Science.gov (United States)

Xue, Yu; Xie, Juanjuan; Fang, Pan; Yao, Jun; Yan, Guoquan; Shen, Huali; Yang, Pengyuan

2018-04-16

Glycosylation is a crucial process in protein biosynthesis. However, the analysis of glycopeptides through MS remains challenging due to the microheterogeneity and macroheterogeneity of the glycoprotein. Selective enrichment of glycopeptides from complex samples prior to MS analysis is essential for successful glycoproteome research. In this work, we systematically investigated the behaviors and performances of boronic acid chemistry, ZIC-HILIC, and PGC of glycopeptide enrichment to promote understanding of these methods. We also optimized boronic acid chemistry and ZIC-HILIC enrichment methods and applied them to enrich glycopeptides from mouse liver. The intact N-glycopeptides were interpreted using the in-house analysis software pGlyco 2.0. We found that boronic acid chemistry in this study preferred to capture glycopeptides with high mannose glycans, ZIC-HILIC enriched most N-glycopeptides and did not show significant preference during enrichment and PGC was not suitable for separating glycopeptides with a long amino acid sequence. We performed a detailed study on the behaviors and performances of boronic acid chemistry, ZIC-HILIC, and PGC enrichment methods and provide a better understanding of enrichment methods for further glycoproteomics research.

South Australia, uranium enrichment

International Nuclear Information System (INIS)

1976-02-01

The Report sets out the salient data relating to the establishment of a uranium processing centre at Redcliff in South Australia. It is conceived as a major development project for the Commonwealth, the South Australian Government and Australian Industry comprising the refining and enrichment of uranium produced from Australian mines. Using the data currently available in respect of markets, demand, technology and possible financial return from overseas sales, the project could be initiated immediately with hexafluoride production, followed rapidly in stages by enrichment production using the centrifuge process. A conceptual development plan is presented, involving a growth pattern that would be closely synchronised with the mining and production of yellowcake. The proposed development is presented in the form of an eight-and-half-year programme. Costs in this Report are based on 1975 values, unless otherwise stated. (Author)

76 FR 17407 - Proposed Subsequent Arrangement

Science.gov (United States)

2011-03-29

... of U.S.-origin atomized depleted uranium- 8wt. % molybdenum powder, 0.3 percent enrichment, from... located at and prepared by KAERI, will be used for qualification testing of plate- type nuclear fuel as... concerning the retransfer of nuclear material of United States origin will not be inimical to the common...

Ningyo Toge uranium enrichment pilot plant comes into full

International Nuclear Information System (INIS)

1982-01-01

The uranium enrichment pilot plant of the Power Reactor and Nuclear Fuel Development Corporation at Ningyo Toge went into full operation on March 26, 1982. This signifies that the front end of the nuclear fuel cycle in Japan, from uranium ore to enrichment, is only a step away from commercialization. On the same day, the pilot plant of uranium processing and conversion to UF 6 , the direct purification of uranium ore into uranium hexafluoride, began batch operation at the same works. The construction of the uranium enrichment pilot plant has been advanced in three stages: i.e. OP-1A with 1000 centrifuges, OP-1B with 3000 centrifuges and OP-2 with 3000 centrifuges. With a total of 7000 centrifuges, the pilot plant, the first enrichment plant in Japan, has now a capacity of supplying enriched uranium for six months operation of a 1,000 MW nuclear power plant. (J.P.N.)

Mapping airborne lead contamination near a metals smelter in Derbyshire, UK: spatial variation of Pb concentration and 'enrichment factor' for tree bark.

Science.gov (United States)

Bellis, D; Cox, A J; Staton, I; McLeod, C W; Satake, K

2001-10-01

Samples of tree bark, collected over an area of 4 km2 near a small non-ferrous metals smelter in Derbyshire, UK, were analysed for Pb and Al by inductively coupled plasma atomic emission spectroscopy (ICP-AES). Analyte concentrations varied from 100 to over 25,000 mg kg-1 and 5 to 1000 mg kg-1, respectively. While an inverse relationship between the Pb content of bark and distance from the smelter was observed, concentrations fluctuated, indicating a variability in sample collection efficiency and problems in standardization. To overcome these effects, the Pb/Al ratio was calculated and subsequently normalized to the average Pb/Al ratio in continental crust (0.00015). On the assumption that the time-averaged concentration of airborne Al in this area is relatively constant and derived principally from wind-blown soil, the measurement represents an anthropogenic 'enrichment factor' (PbEF). PbEF varied from 10,000 to over 1,000,000, and showed a consistent reduction with distance from the smelter. Isolines of equal PbEF were subsequently defined on a map of the sampled area. Pb contamination was greatest in the vicinity of the smelter, and preferential transport along the NW-SE axis of the valley (in which the smelter is situated) was observed. The use of enrichment factors thus proved valuable in defining the relative level of airborne-derived Pb pollution.

Perspectives for the uranium enrichment in Brazil

International Nuclear Information System (INIS)

Senna, J.G.S.M.

1991-01-01

Through an analysis of the electrical energy future in Brazil, the needs for enriched uranium are discussed, and therefore the importance of developing local capability for self-production. A description of the production processes that are well established is given first, then the analysis itself is performed and finally a visualization of the International Market for enriched uranium is shown. (author)

Enrichment and activation of smectite-poor clay

Energy Technology Data Exchange (ETDEWEB)

Sarcevica, Inese; Kostjukovs, Juris; Actint, Andris, E-mail: inese.sarcevicha@gmail.com [Department of Chemistry, University of Latvia, Kr. Valdemara street 48, Riga (Latvia)

2011-06-23

A new method of smectite clay enrichment has been developed. The method is based on dispersing clay in a phosphate solution and sequential coagulation. The product of enrichment is characterized with X-ray powder diffraction, wavelength dispersive X-ray fluorescence spectrometry, differential thermal analysis and thermogravimetry. Sorption of methylene blue and hexadecylpyridinium bromide on raw and purified clays was studied.

Nutrient enrichment increases mortality of mangroves.

Directory of Open Access Journals (Sweden)

Catherine E Lovelock

Full Text Available Nutrient enrichment of the coastal zone places intense pressure on marine communities. Previous studies have shown that growth of intertidal mangrove forests is accelerated with enhanced nutrient availability. However, nutrient enrichment favours growth of shoots relative to roots, thus enhancing growth rates but increasing vulnerability to environmental stresses that adversely affect plant water relations. Two such stresses are high salinity and low humidity, both of which require greater investment in roots to meet the demands for water by the shoots. Here we present data from a global network of sites that documents enhanced mortality of mangroves with experimental nutrient enrichment at sites where high sediment salinity was coincident with low rainfall and low humidity. Thus the benefits of increased mangrove growth in response to coastal eutrophication is offset by the costs of decreased resilience due to mortality during drought, with mortality increasing with soil water salinity along climatic gradients.

Environmental enrichment in farm, zoo, companion and experimental animals

OpenAIRE

Vučinić Marijana

2009-01-01

The paper deals with environmental enrichment for domestic animals at farms, animals in zoos, experimental animals and pet animals. Also, the paper defines and describes different strategies of environmental enrichment. Environmental enrichment is a simple and effective mean of prevention of boredom, behavioral disorders as well as an effective mean of improving animal welfare in farm, zoo, companion and experimental animals. Different items and materials may be used for environmental enrichm...

Method of deuterium isotope separation and enrichment

International Nuclear Information System (INIS)

Benson, S.W.

1978-01-01

A method of separating deuterium, i.e., heavy hydrogen, from certain naturally occurring sources using tuned infrared lasers to selectively decompose specified classes of organic molecules (i.e., RX) into enriched molecular products containing deuterium atoms is described. The deuterium containing molecules are easily separated from the starting material by absorption, distillation or other simple chemical separation techniques and methods. After evaporation such deuterium containing molecules can be burned to form water with an enriched deuterium content or pyrolyzed to form hydrogen gas with an enriched deuterium content. The undecomposed molecules and the other reaction products which are depleted of their deuterium containing species can be catalytically treated, preferably using normal water, to restore the natural abundance of deuterium and such restored molecules can then be recycled

Specific capture of uranyl protein targets by metal affinity chromatography

International Nuclear Information System (INIS)

Basset, C.; Dedieu, A.; Guerin, P.; Quemeneur, E.; Meyer, D.; Vidaud, C.

2008-01-01

To improve general understanding of biochemical mechanisms in the field of uranium toxicology, the identification of protein targets needs to be intensified. Immobilized metal affinity chromatography (IMAC) has been widely developed as a powerful tool for capturing metal binding proteins from biological extracts. However uranyl cations (UO 2 2+ ) have particular physico-chemical characteristics which prevent them from being immobilized on classical metal chelating supports. We report here on the first development of an immobilized uranyl affinity chromatography method, based on the cation-exchange properties of amino-phosphonate groups for uranyl binding. The cation distribution coefficient and loading capacity on the support were determined. Then the stability of the uranyl-bonded phase under our chromatographic conditions was optimized to promote affinity mechanisms. The successful enrichment of uranyl binding proteins from human serum was then proven using proteomic and mass spectral analysis. (authors)

Capability of the electromagnetic isotope-enrichment facility at ORNL

International Nuclear Information System (INIS)

Newman, E.

1982-01-01

The isotope separation program at Oak Ridge National Laboratory (ORNL) prepares and distributes electromagnetically enriched stable isotopes to the worldwide scientific community. Among the topics discussed in the present paper are the methods of enriching isotopes, the limitations that apply to the quantity and final assay of the separation products, and a generalized production flowsheet indicating the capability of the facility. A brief description of each of the production steps, from the selection and preparation of initial feedstock to the recovery and distribution of the isotopically enriched material, is presented. The future of the facility, the continued supply of enriched isotopes, and the response of the program to new and changing requirements are emphasized

Scoping study to expedite development of a field deployable and portable instrument for UF6 enrichment assay

Energy Technology Data Exchange (ETDEWEB)

Chan, George; Valentine, John D.; Russo, Richard E.

2017-09-14

-Term R&D Plan, 2012–2023, one of the IAEA long-term R&D needs is to “develop tools and techniques to enable timely, potentially real-time, detection of HEU (Highly Enriched Uranium) production in LEU (Lowly Enriched Uranium) enrichment facilities” (Milestone 5.2). Because it is common that the next generation of analytical instruments is driven by technologies that are either currently available or just now emerging, one reasonable and practical approach to project the next generation of chemical instrumentation is to track the recent trends and to extrapolate them. This study adopted a similar approach, and an extensive literature review on existing and emerging technologies for UF6 enrichment assay was performed. The competitive advantages and current limitations of different analytical techniques for in-field UF6 enrichment assay were then compared, and the main gaps between needs and capabilities for their field use were examined. Subsequently, based on these results, technologies for the next-generation field-deployable instrument for UF6 enrichment assay were recommended. The study was organized in a way that a suite of assessment metric was first identified. Criteria used in this evaluation are presented in Section 1 of this report, and the most important ones are described briefly in the next few paragraphs. Because one driving force for in-field UF6 enrichment assay is related to the demanding transportation regulation for gaseous UF6, Section 2 contains a review of solid sorbents that convert and immobilized gaseous UF6 to a solid state, which is regarded as more transportation friendly and is less regulated. Furthermore, candidate solid sorbents, which show promise in mating with existing and emerging assay technologies, also factor into technology recommendations. Extensive literature reviews on existing and emerging technologies for UF6 enrichment assay, covering their scientific principles, instrument options, and current limitations are detailed in

Effect of a diet enriched with green-lipped mussel on pain behavior and functioning in dogs with clinical osteoarthritis.

Science.gov (United States)

Rialland, Pascale; Bichot, Sylvain; Lussier, Bertrand; Moreau, Maxim; Beaudry, Francis; del Castillo, Jérôme R E; Gauvin, Dominique; Troncy, Eric

2013-01-01

This study aimed to establish the effect of a diet enriched with green-lipped mussel (GLM) on pain and functional outcomes in osteoarthritic dogs. Twenty-three client-owned dogs with osteoarthritis (OA) were fed a balanced control diet for 30 d and then a GLM-enriched balanced diet for the next 60 d. We assessed peak vertical force (PVF), which is considered to be the gold standard method, at Day (D)0 (start), D30 (end of control diet), and D90 (end of GLM-enriched diet). The owners completed a client-specific outcome measure (CSOM), which is a pain questionnaire, once a week. Motor activity (MA) was continuously recorded in 7 dogs for 12 wk. Concentrations of plasma omega-3 fatty acids were quantified as indicative of diet change. Statistical analyses were linear-mixed models and multinomial logistic regression for repeated measures. The GLM diet (from D30 to D90) resulted in an increase in concentrations of plasma omega-3 fatty acids (P change (P = 0.06), which suggests that the GLM diet had a beneficial effect on gait function. Moreover, PVF (P = 0.0004), CSOM (P = 0.006), and MA (P = 0.02) improved significantly from D0 to D90. In general, the balanced control diet could have contributed to reduced OA symptoms, an effect that was subsequently amplified by the GLM diet.

Use of enriched uranium in Canada's power reactors

International Nuclear Information System (INIS)

Dormuth, K.W.; Jackson, D.P.

2011-01-01

Recent trends in Canadian nuclear power reactor design and proposed development of nuclear power in Canada have indicated the possibility that Canada will break with its tradition of natural uranium fuelled systems, designed for superior neutron economy and, hence, superior uranium utilization. For instance, the Darlington B new reactor project procurement process included three reactor designs, all employing enriched fuel, although a natural uranium reactor design was included at a late stage in the ensuing environmental assessment for the project as an alternative technology. An evaluation of the alternative designs should include an assessment of the environmental implications through the entire fuel cycle, which unfortunately is not required by the environmental assessment process. Examples of comparative environmental implications of the reactor designs throughout the fuel cycle indicate the importance of these considerations when making a design selection. As Canada does not have enrichment capability, a move toward the use of enriched fuel would mean that Canada would be exporting natural uranium and buying back enriched uranium with value added. From a waste management perspective, Canada would need to deal with mill, refinery, and conversion tailings, as well as with the used fuel from its own reactors, while the enrichment supplier would retain depleted uranium with some commercial value. On the basis of reasoned estimates based on publicly available information, it is expected that enrichment in Canada is likely to be more profitable than exporting natural uranium and buying back enriched uranium. Further, on the basis of environmental assessments for enrichment facilities in other countries, it is expected that an environmental assessment of a properly sited enrichment facility would result in approval. (author)

Georges Besse 2. A new era for enrichment

International Nuclear Information System (INIS)

2009-01-01

Since 1978, AREVA group subsidiary EURODIF's Georges Besse plant has been using gaseous diffusion to enrich uranium and meet the requirements of electricity utilities. Georges Besse II plant, which will use far less electricity, will replace George Besse not so long. The Georges Besse II plant is located on the Tricastin nuclear site in southern France. AREVA ensure delivery of uranium enrichment services in accordance with customer expectations. AREVA obtained the right to use URENCO's centrifugation technology on July 3, 2006. This is the process to be used at Georges Besse II. The new uranium enrichment plant will comprise two enrichment units, with a total production capacity of 7.5 million separative work units, which can be extended to 11 million if needed. Each enrichment unit will include: a Centrifuge Assembly Building (CAB), a Centrifuge Utility Building (CUB) with offices and control room, annexes for purification, supply and extraction of uranium hexafluoride (UF 6 ), modules containing the halls that house the centrifuge cascades. The modular design of the Georges Besse II plant will allow production in the first cascade where as the others cascades are build. The first cascade should be operational in the first half of 2009. At an overall cost of 3 billion euros, this project is one of the largest investments of the decade in France On November 24, 2003, AREVA and URENCO signed an agreement under which AREVA would buy 50% of the shares in the Enrichment Technology Company (ETC), which designs and manufactures centrifuges

Material control and accounting requirements for uranium enrichment facilities

International Nuclear Information System (INIS)

Ting, P.

1991-01-01

This paper reports that the U.S. Nuclear Regulatory Commission has defined material control and accounting (MC and A) requirement for low-enriched uranium enrichment plants licensed under 10 CFR parts 40 and 70. Following detailed assessment of potential safeguards issues relevant to these facilities, a new MC and A rule was developed. The primary safeguards considerations are detection of the loss of special nuclear material, detection of clandestine production of special nuclear material of low strategic significance for unauthorized use or distribution, and detection of unauthorized production of uranium enriched to ≥10 wt % U-235. The primary safeguards concerns identified were the large absolute limit of error associated with the material balance closing, the inability to shutdown some uranium enrichment technologies to perform a cleanout inventory of the process system, and the flexibility of some of these technologies to produce higher enrichments. Unauthorized production scenarios were identified for some technologies that could circumvent the detection of the production and removal of 5 kilograms of U-235 as high-enriched uranium through conventional material control and accounting programs. Safeguards techniques, including the use of production and process control information, measurements, and technical surveillance, were identified to compensate for these concerns

Enrichment of reticulocytes from whole blood using aqueous multiphase systems of polymers.

Science.gov (United States)

Kumar, Ashok A; Lim, Caeul; Moreno, Yovany; Mace, Charles R; Syed, Abeer; Van Tyne, Daria; Wirth, Dyann F; Duraisingh, Manoj T; Whitesides, George M

2015-01-01

This paper demonstrates the enrichment of reticulocytes by centrifuging whole blood through aqueous multiphase systems (AMPSs)-immiscible phases of solutions of polymers that form step-gradients in density. The interfaces of an AMPS concentrate cells; this concentration facilitates the extraction of blood enriched for reticulocytes. AMPS enrich reticulocytes from blood from both healthy and hemochromatosis donors. Varying the osmolality and density of the phases of AMPS provides different levels of enrichment and yield of reticulocytes. A maximum enrichment of reticulocytemia of 64 ± 3% was obtained from donors with hemochromatosis. When used on peripheral blood from normal donors, AMPS can provide a higher yield of enriched reticulocytes and a higher proportion of reticulocytes expressing CD71 than differential centrifugation followed by centrifugation over Percoll. Blood enriched for reticulocytes by AMPS could be useful for research on malaria. Several species of malaria parasites show a preference to invade young erythrocytes and reticulocytes; this preference complicates in vitro cultivation of these species in human blood. Plasmodium knowlesi malaria parasites invade normal human blood enriched for reticulocytes by AMPSs at a rate 2.2 times greater (P blood. Parasite invasion in normal blood enriched by AMPS was 1.8 times greater (P blood enriched to a similar reticulocytemia by differential centrifugation followed by centrifugation over Percoll. The enrichment of reticulocytes that are invaded by malaria parasites demonstrates that AMPSs can provide a label-free method to enrich cells for biological research. © 2014 Wiley Periodicals, Inc.

Development of empirical relation for isotope of uranium in enriched uranium matrix

International Nuclear Information System (INIS)

Srivastava, S.K.; Vidyasagar, D.; Jha, S.K.; Tripathi, R.M.

2018-01-01

Uranium enriched in 235 U is required in commercial light water reactors to produce a controlled nuclear reaction. Enrichment allows the 235 U isotopes to be increased from 0.71% to a range between 2% to 5% depending upon requirement. The enriched uranium in the form of sintered UO 2 pellet is used for any commercially operating boiling light water reactors. The enriched uranium fuel bundle surface swipes sample is being analysed to assess the tramp uranium as a quality control parameter. It is known that the 234 U isotope also enriched along with 235 U isotope in conventional gaseous diffusion enrichment process. The information about enrichment percentage of 234 U helps to characterize isotopic properties of enriched uranium. A few reports provide the empirical equation and graphs for finding out the specific activity, activity percentage, activity ratio of 234 U isotopes for enriched uranium. Most of them have not provided the reference for the data used and their source. An attempt has been made to model the relationship between 234 U and 235 U as a function of uranium enrichment at low level

Enrichment situation outside the United States

International Nuclear Information System (INIS)

Anon.

1979-01-01

Different enrichment technologies are briefly characterized which include gaseous diffusion, which is presently the production mainstay of the United States and France; the gaseous centrifuge which is the production plant for Urenco and the technology for future United States enrichment expansion; the aero-dynamic processes which include the jet nozzle (also known as the Becker process) and the fixed-wall centrifuge (also known as the Helikon process); chemical processes; laser isotope separation processes (also referred to in the literature as LIS); and plasma technology

Highly Selective Enrichment of Glycopeptides Based on Zwitterionically Functionalized Soluble Nanopolymers

Science.gov (United States)

Cao, Weiqian; Huang, Jiangming; Jiang, Biyun; Gao, Xing; Yang, Pengyuan

2016-07-01

Efficient glycopeptides enrichment prior to mass spectrometry analysis is essential for glycoproteome study. ZIC-HILIC (zwitterionic hydrophilic interaction liquid chromatography) based glycopeptides enrichment approaches have been attracting more attention for several benefits like easy operating, high enrichment specificity and intact glycopeptide retained. In this study, Poly (amidoamine) dendrimer (PAMAM) was adopted for the synthesis of zwitterionically functionalized (ZICF) materials for glycopeptide enrichment. The multiple branched structure and good solubility of ZICF-PAMAM enables a sufficient interaction with glycopeptides. The ZICF-PAMAM combined with the FASP-mode enrichment strategy exhibits more superior performance compared with the existing methods. It has the minimum detectable concentration of femtomolar level and high recovery rate of over 90.01%, and can efficiently enrich glycopeptides from complex biological samples even for merely 0.1 μL human serum. The remarkable glycopeptides enrichment capacity of ZICF-PAMAM highlights the potential application in in-depth glycoproteome research, which may open up new opportunities for the development of glycoproteomics.

Buckwheat-enriched wheat bread: National market placement possibilities

Directory of Open Access Journals (Sweden)

Sakač Marijana B.

2015-01-01

Full Text Available Quality parameters and the possibility of successful placement of buckwheat-enriched wheat bread on the national market are presented in this paper. Analysis of the market position of buckwheat-enriched wheat bread includes demands, offer and competition. Elements that affect the overall retail price of buckwheat-enriched wheat bread are given in details, along with SWOT analysis and marketing plan including target market, market supply and product marketing mix. According to all performed analyses it could be concluded that this product should be positioned on the national market, especially for people with special needs and requirements.

Uranium enrichment plans and policies

International Nuclear Information System (INIS)

Schwennesen, J.L.

1981-01-01

Significant progress has been made in US efforts to expand its enrichment capacity. The Cascade Improvement Program (CIP) and Cascade Upgrading Program (CUP) are now complete at Oak Ridge and Paducah and almost complete at Portsmouth. Considerable progress has also been made in constructing the Gas Centrifuge Enrichment Plant (GCEP), and physical construction of the first process building is well under way. Current plans are to have two process buildings on-line by 1989 with the remaining six buildings to be added sequentially as needed to meet demand. The status of DOE enrichment services contracts is essentially unchanged from that reported at last year's seminar. The OUEA latest forecast of nuclear power growth, however, is considerably lower than reported last year, although a leveling trend is becoming apparent. The Variable Tails Assay Option (VTAO) of the AFC contract was made available for the third time for FY 1983. The DOE inventories of natural uranium still remain high. The Department of Energy will dispose of this material by using it for Government programs and for enrichment plant operations. It appears that Government inventories of uranium are adequate through at least the mid-1990s. It remains DOE policy not to dispose of its natural uranium stocks through direct sales in the marketplace, except for very small quantities or if an emergency situation would exist and all reasonable attempts had been made, without success, to obtain natural uranium from commercial sources. Finally, with regard to DOE plans on future transaction tails assays, it still appears likely that the current 0.20 percent uranium-235 reference tails assay will be maintained until well into the 1990s, at which time it might be increased up to 0.25 percent uranium-235

Recent developments in the United States uranium enrichment enterprise

International Nuclear Information System (INIS)

Longenecker, J.R.

1987-01-01

In the near term, DOE is reducing production costs at the gaseous diffusion plants (GDPs), and we've made significant progress already. GDP production costs are expected to decline even further in the near future. DOE is also negotiating new power contracts for the GDPs. The new power contracts, capital improvements, and the use of more unfirm power should reduce our GDP average cost of production to about $60/SWU in the 1990s. Significant technical progress on the Atomic Vapor Laser Isotope Separation (AVLIS) advanced enrichment technology has been made recently. The highlight has been a series of half-scale integrated enrichment experiments using the Laser Demonstration Facility and the Mars separator. We are also ready to initiate testing in the full-scale Separator Demonstration Facility, including a 100 hour run that will vaporize over 5 tons of uranium. DOE is developing plans to restructure the enterprise into a more businesslike entity. The key objective in 1987 is to work with Congress to advance the restructuring of the U.S. uranium enrichment enterprise, to assure its long term competitiveness. We hope to establish in law the charter, objectives, and goals for the restructured enterprise. DOE expects that the world price for enrichment services will continue to decrease in the future. There should be sufficient excess enrichment capacity in the future to assure that competition will be keen. Such a healthy, competitive, world enrichment market will be beneficial to both suppliers and consumers of uranium enrichment services. (J.P.N.)

Comparison of microbial DNA enrichment tools for metagenomic whole genome sequencing.

Science.gov (United States)

Thoendel, Matthew; Jeraldo, Patricio R; Greenwood-Quaintance, Kerryl E; Yao, Janet Z; Chia, Nicholas; Hanssen, Arlen D; Abdel, Matthew P; Patel, Robin

2016-08-01

Metagenomic whole genome sequencing for detection of pathogens in clinical samples is an exciting new area for discovery and clinical testing. A major barrier to this approach is the overwhelming ratio of human to pathogen DNA in samples with low pathogen abundance, which is typical of most clinical specimens. Microbial DNA enrichment methods offer the potential to relieve this limitation by improving this ratio. Two commercially available enrichment kits, the NEBNext Microbiome DNA Enrichment Kit and the Molzym MolYsis Basic kit, were tested for their ability to enrich for microbial DNA from resected arthroplasty component sonicate fluids from prosthetic joint infections or uninfected sonicate fluids spiked with Staphylococcus aureus. Using spiked uninfected sonicate fluid there was a 6-fold enrichment of bacterial DNA with the NEBNext kit and 76-fold enrichment with the MolYsis kit. Metagenomic whole genome sequencing of sonicate fluid revealed 13- to 85-fold enrichment of bacterial DNA using the NEBNext enrichment kit. The MolYsis approach achieved 481- to 9580-fold enrichment, resulting in 7 to 59% of sequencing reads being from the pathogens known to be present in the samples. These results demonstrate the usefulness of these tools when testing clinical samples with low microbial burden using next generation sequencing. Copyright © 2016 Elsevier B.V. All rights reserved.

Status report on uranium enrichment associates

International Nuclear Information System (INIS)

Langley, R.A. Jr.; O'Donnell, A.J.; Garrett, G.A.

1977-01-01

Uranium Enrichment Associates (UEA) had as its priority project financing, an approach in which the total project is financially self-liquidating. UEA worked with financial institutions to define the combination of assurances and guarantees required by lenders in order to provide the required debt funding. UEA's assets against which the debt liability for the plant would be balanced would be the facilities under construction and the equipment on order. On the customer side, there was major concern on the part of the utilities of whether private industry would be able to complete and operate the plant owing to many of the same possibilities which concerned financial institutions. The disparity between the conditions under which financing could be obtained and the terms acceptable to utilities was a significant element in EUA's choice of process to use for its enrichment plants. UEA's technical staff then began to parallel conceptual designs of gaseous diffusion and gas cenrifuge plants. UEA negotiated with ERDA on the terms of a Cooperative Arrangement, within the provisions of the NFAA, providing the minimum conditions necessary to obtain financing and contracts with utilities for enrichment sources. The UEA plant has several features different from the ERDA plants. The UEA plant used only two basic stage sizes. The UEA design employed four main process buildings. The partners in UEA have mutually agreed to follow the private uranium enrichment project to a logical conclusion. 6 figures

Automated assay of uranium solution concentration and enrichment

International Nuclear Information System (INIS)

Horley, E.C.; Gainer, K.; Hansen, W.J.; Kelley, T.A.; Parker, J.L.; Sampson, T.E.; Walton, G.; Jones, S.A.

1992-01-01

For the first time, the concentration and enrichment of uranium solutions can be measured in one step. We have developed a new instrument to automatically measure the concentration and enrichment of uranium solutions through the adaptation of a commercial robot. Two identical solution enrichment systems are being installed in the Portsmouth Gaseous Diffusion Plant. These automated systems will reduce radiation exposure to personnel and increase the reliability and repeatability of the measurements. Each robotic system can process up to 40 batch and 8 priority samples in an unattended mode. Both passive gamma-ray and x-ray fluorescence (XRF) analyses are performed to determine total uranium concentration and 235 U enrichment. Coded samples are read by a bar-code reader to determine measurement requirements, then assayed by either or both of the gamma-ray and XRF instruments. The robot moves the sample containers and operates all shield doors and shutters, reducing hardware complexity. If the robots is out of service, an operator can manually perform all operations

Method of deuterium isotope separation and enrichment

International Nuclear Information System (INIS)

Benson, S.W.

1979-01-01

A method is described for separating and enriching deuterium containing molecules comprising the steps of: providing a source of organic molecules containing a normal abundance of deuterium atoms, the organic molecules having a structural formula RX, in which R is an organic radical selected from ethyl, isopropyl, t-butyl and 3-cyclopentenyl, and in which X is selected from F, Cl, Br and OH, and wherein R represents 3-cyclopentenyl, X may additionally represent H; exposing the molecules to the radiation of at least one pulsed infrared laser source which has been specifically tuned and focussed to selectively decompose RX molecules containing deuterium to form an enriched olefin specie containing deuterium, and HX; and separating the deuterium enriched olefin specie from the undecomposed deuterium depleted RX molecules and HX. (author)

Selenium Enrichment of Horticultural Crops.

Science.gov (United States)

Puccinelli, Martina; Malorgio, Fernando; Pezzarossa, Beatrice

2017-06-04

The ability of some crops to accumulate selenium (Se) is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

Selenium Enrichment of Horticultural Crops

Directory of Open Access Journals (Sweden)

Martina Puccinelli

2017-06-01

Full Text Available The ability of some crops to accumulate selenium (Se is crucial for human nutrition and health. Selenium has been identified as a cofactor of the enzyme glutathione peroxidase, which is a catalyzer in the reduction of peroxides that can damage cells and tissues, and can act as an antioxidant. Plants are the first link in the food chain, which ends with humans. Increasing the Se quantity in plant products, including leafy and fruity vegetables, and fruit crops, without exceeding the toxic threshold, is thus a good way to increase animal and human Se intake, with positive effects on long-term health. In many Se-enriched plants, most Se is in its major organic form. Given that this form is more available to humans and more efficient in increasing the selenium content than inorganic forms, the consumption of Se-enriched plants appears to be beneficial. An antioxidant effect of Se has been detected in Se-enriched vegetables and fruit crops due to an improved antioxidative status and to a reduced biosynthesis of ethylene, which is the hormone with a primary role in plant senescence and fruit ripening. This thus highlights the possible positive effect of Se in preserving a longer shelf-life and longer-lasting quality.

Enrichment and Preservation of Architectural Knowledge

DEFF Research Database (Denmark)

Beetz, Jakob; Blümel, Ina; Dietze, Stefan

2016-01-01

In the context of the EU FP7 DURAARK project (2013–2016), inter-disciplinary methods, technologies and tools have been researched and developed, that support the Long Term Preservation of semantically enriched digital representations of built structures. The results of the research efforts include...... approaches of semi-automatically deriving building models from point cloud data sets acquired from laser scans and the integration and overlay of such representations with explicit Building Information Models (BIM). We introduce novel ways for the further semantic enrichment of such hybrid building models...

Uranium enrichment: heading for the abyss

International Nuclear Information System (INIS)

Norman, C.

1983-01-01

This article discusses the federal government's $2.3 billion a year business enriching uranium for nuclear power plants which is heading toward a major crisis. Due to miscalculations by the Department of Energy, it is caught with billions of dollars of construction in progress just as projected demand for enriched uranium is decreasing. At the center of the controversy is the Gas Centrifuge Plant at Portsmouth, Ohio - estimated to cost $10 billion dollars. A review of how DOE got into this situation and how they plan to solve it is presented

Isotopic enrichment in a plasma centrifuge

International Nuclear Information System (INIS)

Del Bosco, E.; Dallaqua, R.S.; Ludwig, G.O.; Bittencourt, J.A.

1986-05-01

A rotating fully ionized plasma column was produced in a vacuum-arc centrifuge. The apparatus is described and new results for the rotational velocity and isotope enrichment of carbon and metal plasmas are shown. The ion rotation velocity is derived from electrostatic probes measurents and from the azimuthal displacement of the material deposited behind of a narrow slit. The isotope enrichment is measured with a modified quadrupole mass spectrometer, which determines, in situ, the relative abundance of the isotopes at the end of the plasm column at various radil positions. (Author) [pt

Simulating cosmic metal enrichment by the first galaxies

NARCIS (Netherlands)

Pallottini, A.; Ferrara, A.; Gallerani, S.; Salvadori, S.; D'Odorico, V.

We study cosmic metal enrichment via adaptive mesh refinement hydrodynamical simulations in a (10 Mpc h-1)3 volume following the Population III (PopIII)-PopII transition and for different PopIII initial mass function (IMFs). We have analysed the joint evolution of metal enrichment on galactic and

Fast Enrichment Screening for Safeguards Applications

International Nuclear Information System (INIS)

Simpson, A.; McElhaney, S.

2010-01-01

Methods for rapid non-destructive uranium enrichment classification of large containers are of importance to safeguards and counter-terrorism agencies. There is a need to quickly categorize and segregate suspect items as 'depleted' or 'enriched' on a 'Go/No Go' basis. Recent improvements in gamma spectroscopy technologies have provided the capability to perform rapid field analysis using portable and hand-held devices such as battery-operated medium and high resolution detectors (including lanthanum halide and high purity germanium). Furthermore a new generation of portal monitors are currently under development with advanced spectroscopic capabilities. Instruments and technologies that were previously the domain of complex lab systems are now widely available as touch-screen 'off-the-shelf' units. Despite such advances, the task of enrichment analysis remains a complex exercise. This is particularly so when surveying large items such as drums and crates containing debris of unknown density and composition contaminated with uranium. The challenge is equally applicable to safeguards inspectors evaluating large items and for interdiction of illicit special nuclear materials in mass transport e.g. shipping containers at ports and borders. The variable shielding, container size, lack of matrix knowledge, wall thickness and self-shielding compound this problem. Performing an accurate assessment within the short count time window demanded of the field operative, leads to the need for a reliable method that can adapt to such conditions and is robust to a wide dynamic range of counting statistics. Several methods are evaluated with reference to the performance metrics defined in applicable standards. The primary issue is to minimize the bias that can result from attenuation effects, particularly as the gamma emissions from U235 are low energy and therefore highly susceptible to absorption in large containers with metal scrap. Use of other radiometric signatures such as

A Review of Subsequence Time Series Clustering

Directory of Open Access Journals (Sweden)

Seyedjamal Zolhavarieh

2014-01-01

Full Text Available Clustering of subsequence time series remains an open issue in time series clustering. Subsequence time series clustering is used in different fields, such as e-commerce, outlier detection, speech recognition, biological systems, DNA recognition, and text mining. One of the useful fields in the domain of subsequence time series clustering is pattern recognition. To improve this field, a sequence of time series data is used. This paper reviews some definitions and backgrounds related to subsequence time series clustering. The categorization of the literature reviews is divided into three groups: preproof, interproof, and postproof period. Moreover, various state-of-the-art approaches in performing subsequence time series clustering are discussed under each of the following categories. The strengths and weaknesses of the employed methods are evaluated as potential issues for future studies.

A review of subsequence time series clustering.

Science.gov (United States)

Zolhavarieh, Seyedjamal; Aghabozorgi, Saeed; Teh, Ying Wah

2014-01-01

Clustering of subsequence time series remains an open issue in time series clustering. Subsequence time series clustering is used in different fields, such as e-commerce, outlier detection, speech recognition, biological systems, DNA recognition, and text mining. One of the useful fields in the domain of subsequence time series clustering is pattern recognition. To improve this field, a sequence of time series data is used. This paper reviews some definitions and backgrounds related to subsequence time series clustering. The categorization of the literature reviews is divided into three groups: preproof, interproof, and postproof period. Moreover, various state-of-the-art approaches in performing subsequence time series clustering are discussed under each of the following categories. The strengths and weaknesses of the employed methods are evaluated as potential issues for future studies.

A Review of Subsequence Time Series Clustering

Science.gov (United States)

Teh, Ying Wah

2014-01-01

Clustering of subsequence time series remains an open issue in time series clustering. Subsequence time series clustering is used in different fields, such as e-commerce, outlier detection, speech recognition, biological systems, DNA recognition, and text mining. One of the useful fields in the domain of subsequence time series clustering is pattern recognition. To improve this field, a sequence of time series data is used. This paper reviews some definitions and backgrounds related to subsequence time series clustering. The categorization of the literature reviews is divided into three groups: preproof, interproof, and postproof period. Moreover, various state-of-the-art approaches in performing subsequence time series clustering are discussed under each of the following categories. The strengths and weaknesses of the employed methods are evaluated as potential issues for future studies. PMID:25140332

Report of Sectional Committee on Industrialization of Uranium Enrichment

International Nuclear Information System (INIS)

1981-01-01

In order to accelerate the development and utilization of atomic energy which is the core of the substitute energies for petroleum, it is indispensable requirement to establish independent fuel cycle as the base. In particular, the domestic production of enriched uranium is necessary to eliminate the obstacles to secure the energy supply in Japan. The construction and operation of the pilot plant for uranium enrichment by centrifugal separation method have progressed smoothly, and the technical base for the domestic production of enriched uranium is being consolidated. For the time being, the service of uranium enrichment is given by USA and France, but it is expected that the short supply will arise around 1990. The start of operation of the uranium enrichment plant in Japan is scheduled around 1990, and the scale of the plant will be expanded stepwise thereafter. The scale of production is assumed as 3000 t SWU/year in 2000. Prior to this commercial plant, the prototype plant of up to 250 t SWU/year capacity will be operated in 1986, starting the production of centrifugal separators in 1983. The production line for centrifugal separators will have the capacity of up to 125 t SWU/year. The organization for operating these plants, the home production of natural uranium conversion, the uranium enrichment by chemical method and others are described. (Kako, I.)

Application research of improved 235U enrichment meter

International Nuclear Information System (INIS)

Liu Daming; Wu Xin; Lu Zhao; Tang Peijia; Lu Feng; Wang Yunmei

1998-01-01

A prototype 235 U enrichment meter based on NaI(Tl) γ spectroscopy is improved and it works under the principle of that the enrichment of 235 U is proportional to the radioactivity of 185 keV γ-ray when the sample is thick infinitely. The data of radioactivity from 235 U can be collected by a notebook computer and the interface control software is written using C++ language. The meter was tested and calibrated using standard fuel rods in fuel fabrication plant. For single fuel rod, the measured value of 235 U enrichment is agreeable with declared value within-1.0%-2.8%

Schoolwide Enrichment Model: Challenging All Children to Excel

Science.gov (United States)

Beecher, Margaret

2010-01-01

This article summarizes how the components of the Schoolwide Enrichment Model were used to dramatically reduce the achievement gap in a school with a high at-risk student population. The theories of enrichment and instructional differentiation replaced an existing remedial paradigm and a strength-based methodology was embraced by the school…

Work-Family Enrichment: the Positive Side of Roles of Accumulation

Directory of Open Access Journals (Sweden)

Kadma Maia

2015-08-01

Full Text Available This article aims at understand up how the interaction can promote work-family enrichment in the roles developed by the Executive Secretaries of a public university. The approach used was the qualitative analysis research and data collection technique employed a semi-structured interview, applied to twenty executive secretaries, employed at the public universities. For the data interpretation, we used the technique of content analysis. The analytical results identified the existence of enrichment in this interaction. The learning opportunity to was mentioned as one of the most enriching element of the work, besides the family values as family enriching element. The family support and experience emerged as enrichment phenomena common to both domains. Regarding the implications of work-family interaction, the most perceived implications by respondents were: increased knowledge and skills, material and psychological benefits, improved quality of life and personal and professional fulfillment. The conclusion is that one should not emphasize the negative side of the work-family interaction if there are favorable resources to enrich this relationship. One should also value the positive side of the interaction to seek a balance between the demands of work and the ones of family is equally important, since the participation of Secretaries in family and work roles proved to be necessary and challenging and it can provide enrichment to the executive secretary roles in their work place.

Development of an On-Line Uranium Enrichment Monitor

International Nuclear Information System (INIS)

Xuesheng, L.; Guorong, L.; Yonggang, Z.; Xueyuan, H. X.-Y.

2015-01-01

An on-line enrichment monitor was developed to measure the enrichment of UF6 flowing through the processing pipes in centrifuge uranium enrichment plant. A NaI(Tl) detector was used to measure the count rates of the 186 keV gamma ray emitted from 235U, and the total quantity of uranium was determined from thermodynamic characteristics of gaseous uranium hexafluoride. The results show that the maximum relative standard deviation is less than 1% when the measurement time is 120 s or more and the pressure is more than 2 kPa in the measurement chamber. There are two working models for the monitor. The monitor works normally in the continuous model, When the gas's pressure in the pipe fluctuates greatly, it can work in the intermittent model, and the measurement result is very well. The background of the monitor can be measured automatically periodically. It can control automatically electromagnetic valves open and close, so as to change the gas's quantity in the chamber. It is a kind of unattended and remote monitor, all of data can be transfer to central control room. It should be effective for nuclear materials accountability verifications and materials balance verification at uranium enrichment plant by using the monitor to monitor Uranium enrichment of gaseous uranium hexafluoride in the output end of cascade continuously. (author)

Successful enrichment of the ubiquitous freshwater acI Actinobacteria.

Science.gov (United States)

Garcia, Sarahi L; McMahon, Katherine D; Grossart, Hans-Peter; Warnecke, Falk

2014-02-01

Actinobacteria of the acI lineage are often the numerically dominant bacterial phylum in surface freshwaters, where they can account for > 50% of total bacteria. Despite their abundance, there are no described isolates. In an effort to obtain enrichment of these ubiquitous freshwater Actinobacteria, diluted freshwater samples from Lake Grosse Fuchskuhle, Germany, were incubated in 96-well culture plates. With this method, a successful enrichment containing high abundances of a member of the lineage acI was established. Phylogenetic classification showed that the acI Actinobacteria of the enrichment belonged to the acI-B2 tribe, which seems to prefer acidic lakes. This enrichment grows to low cell densities and thus the oligotrophic nature of acI-B2 was confirmed. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

Requirements for enrichment tools

NARCIS (Netherlands)

Boer, A.; Winkels, R.; Trompper, M.

2016-01-01

This report gives a high level overview of requirements for Enrichment tools in the Openlaws.eu project. Openlaws.eu aims to initiate a platform and develop a vision for Big Open Legal Data (BOLD): an open framework for legislation, case law, and legal literature from across Europe.

The Acute Effects of Intermittent Light Exposure in the Evening on Alertness and Subsequent Sleep Architecture.

Science.gov (United States)

Yang, Minqi; Ma, Ning; Zhu, Yingying; Su, Ying-Chu; Chen, Qingwei; Hsiao, Fan-Chi; Ji, Yanran; Yang, Chien-Ming; Zhou, Guofu

2018-03-15

Exposure to bright light is typically intermittent in our daily life. However, the acute effects of intermittent light on alertness and sleep have seldom been explored. To investigate this issue, we employed within-subject design and compared the effects of three light conditions: intermittent bright light (30-min pulse of blue-enriched bright light (~1000 lux, ~6000 K) alternating with 30-min dim normal light (~5 lux, ~3600 K) three times); continuous bright light; and continuous dim light on subjective and objective alertness and subsequent sleep structure. Each light exposure was conducted during the three hours before bedtime. Fifteen healthy volunteers (20 ± 3.4 years; seven males) were scheduled to stay in the sleep laboratory for four separated nights (one for adaptation and the others for the light exposures) with a period of at least one week between nights. The results showed that when compared with dim light, both intermittent light and continuous bright light significantly increased subjective alertness and decreased sleep efficiency (SE) and total sleep time (TST). Intermittent light significantly increased objective alertness than dim light did during the second half of the light-exposure period. Our results suggested that intermittent light was as effective as continuous bright light in their acute effects in enhancing subjective and objective alertness and in negatively impacting subsequent sleep.

The Acute Effects of Intermittent Light Exposure in the Evening on Alertness and Subsequent Sleep Architecture

Directory of Open Access Journals (Sweden)

Minqi Yang

2018-03-01

Full Text Available Exposure to bright light is typically intermittent in our daily life. However, the acute effects of intermittent light on alertness and sleep have seldom been explored. To investigate this issue, we employed within-subject design and compared the effects of three light conditions: intermittent bright light (30-min pulse of blue-enriched bright light (~1000 lux, ~6000 K alternating with 30-min dim normal light (~5 lux, ~3600 K three times; continuous bright light; and continuous dim light on subjective and objective alertness and subsequent sleep structure. Each light exposure was conducted during the three hours before bedtime. Fifteen healthy volunteers (20 ± 3.4 years; seven males were scheduled to stay in the sleep laboratory for four separated nights (one for adaptation and the others for the light exposures with a period of at least one week between nights. The results showed that when compared with dim light, both intermittent light and continuous bright light significantly increased subjective alertness and decreased sleep efficiency (SE and total sleep time (TST. Intermittent light significantly increased objective alertness than dim light did during the second half of the light-exposure period. Our results suggested that intermittent light was as effective as continuous bright light in their acute effects in enhancing subjective and objective alertness and in negatively impacting subsequent sleep.

Enrichment overview: fierce competition in a buyers' market

International Nuclear Information System (INIS)

Wolf, W.H.

1985-01-01

There is considerable market uncertainty about what the non-US suppliers of enrichment will do to compete in the light of recent Department of Energy action on technology, price and contracts. But virtually whatever happens, it will be the enrichment customer who will benefit. The ''buyers market'' of today will continue. (author)

47 CFR 1.2111 - Assignment or transfer of control: unjust enrichment.

Science.gov (United States)

2010-10-01

... enrichment. 1.2111 Section 1.2111 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL PRACTICE AND...: unjust enrichment. (a) Reporting requirement. An applicant seeking approval for a transfer of control or... an option to purchase; below market financing). (b) Unjust enrichment payment: set-aside. As...

Centar's gas centrifuge enrichment project

International Nuclear Information System (INIS)

Abajian, V.V.; Fishman, A.M.

1976-01-01

Plans for the building and operating of Centar Associates gas centrifuge uranium enrichment plant are described. Operating costs and machine manufacture are considered. Commitments with the utilities are summarised. (U.K.)

Monitoring the enrichment of the UF6 in the pipework of a gas centrifuge enrichment plant

International Nuclear Information System (INIS)

Packer, T.W.; Close, D.A.; Pratt, J.C.

1987-01-01

Research in the UK and the US has resulted in the development of a nondestructive assay instrument which can confirm the presence of low enriched uranium, on a rapid Go, No-Go basis, in cascade header pipework in the centrifuge enrichment plant at Capenhurst. The instrument is based on gamma-ray spectrometry and x-ray fluorescence analysis. It allows pipes, 120mm outer diameter, to be inspected in a total measurement time of approximately 30 minutes. This paper describes the techniques developed and includes the results obtained during a demonstration to, and preliminary in-plant measurements by, members of the IAEA and EURATOM Inspectorates at Capenhurst

Determination of uranium enrichment by using gamma-spectrometric methods

International Nuclear Information System (INIS)

Kutnyj, D.V.; Telegin, Yu.N.; Odejchuk, N.P.; Mikhailov, V.A.; Tovkanets, V.E.

2009-01-01

By using commercial analysis programs MGAU (LLNL, USA) and FRAM (LANL, USA) the summary error of gamma-spectrometric uranium enrichment measurements was investigated. Uranium samples with enrichments of 0,71; 4,46 and 20,1 % were measured. The coaxial high purity germanium detector (type GC) and the planar germanium detector (type LEGe) were used as gamma-radiation detectors. It was shown that experimental equipment and mathematical software available in NSC KIPT allow us to measure uranium enrichment by nondestructive method with accuracy of not worse than 2%.

The nature of mathematical enrichment: a case study of implementation

Directory of Open Access Journals (Sweden)

Jennifer Susan Piggott

2007-12-01

Full Text Available This paper reports a framework for describing the nature of mathematics enrichment that emerged from a case study based on the work of the NRICH Project (www.nrich.maths.org team when producing “mathematics enrichment trails” (an ordered set of related mathematics problems and support materials. A range of data sources, including the trails, trail development sessions, related literature and the views of colleagues were used to inform the findings. The data were analysed using NVivo and involved the development of two complementary coding systems. One, drawn from the data itself, gave evidence of views of the content aspects of mathematical enrichment. The other, specifically designed and informed by the literature, was used to aid the analysis of the roles of teaching and learning inherent in views of enrichment described by participants. The framework describes the content of an enrichment curriculum as well as implications for teaching and learning, the experiences of learners and the features of settings where this occurs. To support this, some detail is provided on the role, nature and purpose of problem-solving and what constitutes a good problem. While emerging from a particular context, the framework highlights the need for debate concerning the audience for mathematics enrichment, particularly in questioning the commonly held belief that its value is in supporting the needs of the mathematically most able. The framework also has potential value through offering a focus for debate within the wider community concerning the nature of mathematics enrichment and as a reference point for evaluating the potential of existing or new curriculum to deliver mathematics enrichment.

Unattended Monitoring of HEU Production in Gaseous Centrifuge Enrichment Plants using Automated Aerosol Collection and Laser-based Enrichment Assay

International Nuclear Information System (INIS)

Anheier, Norman C.; Bushaw, Bruce A.

2010-01-01

Nuclear power is enjoying rapid growth as government energy policies and public demand shift toward low carbon energy production. Pivotal to the global nuclear power renaissance is the development and deployment of robust safeguards instrumentation that allows the limited resources of the IAEA to keep pace with the expansion of the nuclear fuel cycle. Undeclared production of highly enriched uranium (HEU) remains a primary proliferation concern for modern gaseous centrifuge enrichment plants (GCEPs), due to their massive separative work unit (SWU) processing power and comparably short cascade equilibrium timescale. The Pacific Northwest National Laboratory is developing an unattended safeguards instrument, combining continuous aerosol particulate collection with uranium isotope assay, to provide timely detection of HEU production within a GCEP. This approach is based on laser vaporization of aerosol particulates, followed by laser spectroscopy to characterize the uranium enrichment level. Our prior investigation demonstrated single-shot detection sensitivity approaching the femtogram range and relative isotope ratio uncertainty better than 10% using gadolinium as a surrogate for uranium. In this paper we present measurement results on standard samples containing traces of depleted, natural, and low enriched uranium, as well as measurements on aerodynamic size uranium particles mixed in background materials (e.g., dust, minerals, soils). Improvements and optimizations in the detection electronics, signal timing, calibration, and laser alignment have lead to significant improvements in detection sensitivity and enrichment accuracy, contributing to an overall reduction in the false alarm probability. The sample substrate media was also found to play a significant role in facilitating laser-induced vaporization and the production of energetic plasma conditions, resulting in ablation optimization and further improvements in the isotope abundance sensitivity.

Recovery of Three Arctic Stream Reaches From Experimental Nutrient Enrichment.

Science.gov (United States)

Green, A. C.; Benstead, J. P.; Deegan, L. A.; Peterson, B. J.; Bowden, W. B.; Huryn, A. D.; Slavik, K.; Hershey, A. E.

2005-05-01

We examined multi-year patterns in community recovery from experimental low-concentration nutrient (N+P and P only) enrichment in three reaches of two Arctic tundra streams (Kuparuk River and Oksrukuyik Creek) on the North Slope of Alaska (USA). Rates of recovery varied among community components and depended on duration of enrichment (2 to 13 consecutive growing seasons). Biomass and C:P ratio of epilithic algae returned to reference levels rapidly (within 2 years), regardless of enrichment duration. Bryophyte cover, which increased greatly after long-term enrichment (>8 years), recovered to reference levels only after 7 years, when a storm scoured most remnant moss in the recovering reach. Persistence of bryophytes slowed recovery rates of insect taxa that had either been positively (e.g., Ephemerella, most chironomid taxa) or negatively (e.g., Orthocladius rivulorum) affected by this shift in dominant primary producer and its consequence for benthic habitat. Growth of Arctic grayling (adults and young-of-year), the top predator, returned to reference rates within two years. Recovery of these Arctic stream ecosystems from nutrient enrichment was consequently controlled largely by interactions between duration of enrichment and physical disturbance, mediated through physical habitat shifts caused by bryophytes.

On the enrichment of hydrophobic organic compounds in fog droplets

Science.gov (United States)

Valsaraj, K. T.; Thoma, G. J.; Reible, D. D.; Thibodeaux, L. J.

The unusual degree of enrichment of hydrophobic organics in fogwater droplets reported by several investigators can be interpreted as a result of (a) the effects of temperature correction on the reported enrichment factors, (b) the effects of colloidal organic matter (both filterable and non-filterable) in fog water and (c) the effects of the large air-water interfacial adsorption of neutral hydrophobic organics on the tiny fog droplets. The enrichment factor was directly correlated to the hydrophobicity (or the activity coefficient in water) of the compounds, as indicated by their octanol-water partition constants. Compounds with large octanol-water partition coefficients (high activity coefficients in water) showed the largest enrichment. Available experimental data on the adsorption of hydrophobic compounds at the air-water interface and on colloidal organic carbon were used to show that the large specific air-water interfacial areas of fog droplets contribute significantly to the enrichment factor.

Uranium enrichment. Industrial and commercial aspect

International Nuclear Information System (INIS)

Lamorlette, G.

1983-01-01

The uranium enrichment, a key stage in the fuel cycle of light-water nuclear power stations, applies sophisticated and protected techniques in installations on a very large scale. This article shows how there was a sudden change from a monopoly position in production to a severe competition in a market which is depressed today but offers good prospects for the future. It indicates how the enrichment industrialist have adapted themselves to the fluctuations of the demand, while safeguarding the reliability of the rendered service and the necessary security of supplies for the proper development of the nuclear electric power [fr

Some engineering considerations when designing centrifuge enrichment plants

International Nuclear Information System (INIS)

Edwards, T.T.

1982-01-01

A review is given of the three main areas where flexibility is needed in the design of centrifuge enrichment plants. These are: the need to cope with market requirements, the limitations imposed by currently available centrifuges and ever advancing centrifuge technology. Details of BNFL's experience with centrifuge enrichment at Capenhurst are presented. (U.K.)

76 FR 30326 - Proposed Subsequent Arrangement

Science.gov (United States)

2011-05-25

... content of 28.276 kg (24.541 ekg) of U.S.-origin highly enriched uranium (HEU) (26.342 kg U-235) and 0.0048 g of plutonium contained in three HEU driver fuels that have been irradiated in the YAYOI nuclear... three HEU driver fuels from the core of YAYOI to be cut and de-cladded in the reactor room into...

Low enrichment of uranium in the light of the nuclear weapon problem

International Nuclear Information System (INIS)

Barstad, G.

1979-09-01

A difficult problem in the immediate future will be to direct civil nuclear technology in such a way that the ability to produce nuclear weapons by additional countries is prevented. There are two main problems. First, enrichment plants can be used to produce high enriched uranium, which can be used in nuclear weapons, as well as low enriched reactor fuel. Second, plutonium produced during reactor operation can be used as nuclear weapon material, as well as for nuclear fuel. The problem discussed here is particularly the development of an enrichment process which is economic for low enriched reactor fuel, but which may not easily be adapted to produce high enriched uranium. (JIW)

Behavioral responses of three lemur species to different food enrichment devices.

Science.gov (United States)

Shapiro, Morgan E; Shapiro, Hannah G; Ehmke, Erin E

2018-05-01

Environmental enrichment is a tool used to promote the welfare and well-being of captive animals by encouraging the display of species-specific behaviors and reducing the stress or boredom induced by captive environments. Lemurs are highly endangered, yet few studies have analyzed the behavioral impacts of enrichment on captive populations. We studied the impacts of two novel enrichment devices on three lemur species (ring-tailed lemurs [Lemur catta], red-ruffed lemurs [Varecia rubra], and Coquerel's sifaka [Propithecus coquereli]) to determine both the overall and species-specific impacts of enrichment on lemur behavior. We recorded lemur behavior using the continuous sampling method to obtain behavior duration and analyzed our results using ANOVA Repeated Measures. Results showed enrichment effectiveness differed for each species and that different enrichment devices had varying impacts on lemur behavior across all species. We attributed the differences in species-specific responses to the unique locomotor patterns and methods of diet acquisition of each species, and the variances in behavioral responses across all species to the characteristics of each device. Our study highlights the importance of species-specific enrichment and encourages further research in this field in order to maximize the positive effects of enrichment, which in turn has the potential to affect the overall well-being of captive populations. © 2018 Wiley Periodicals, Inc.

Determining method and device for enrichment distribution inside of fuel assembly

International Nuclear Information System (INIS)

Hirano, Yasushi; Hida, Kazuki; Sakurada, Koichi.

1997-01-01

An enrichment degree at an initial burning stage of each of fuel rods of a BWR type reactor assembly is divided into groups. The enrichment degree at the initial burning stage of each of the groups is inputted, and the burning period from the loading to the taking out is divided into a plurality of burning steps. Nuclear characteristics of fuel assemblies such as the power of fuel rods, R-factor and infinite multiplication factor in each of the burning steps are estimated. The enrichment degree of the group of enrichment degree at the initial burning stage and the estimated power of fuel rods in a reactor operation state during the burning step are stored in the memory. A sensitivity coefficient showing the amount of change of the power of fuel rods in the burning step relative to the change of the enrichment degree of the group of enrichment degree is evaluated. A weighing function in the burning step is inputted. The maximum value of the product of the weighing function and the power of fuel rods throughout the entire burning steps is determined as an aimed function. Optimization calculation is conducted for determining the enrichment degree of the group so as to minimize the aimed function thereby determining the distribution of the enrichment degree. (N.H.)

Technical and economic aspects of new gaseous diffusion uranium enrichment capacity

International Nuclear Information System (INIS)

Langley, R.A. Jr.; O'Donnell, A.J.

1977-01-01

Work is well advanced on design and construction of the next major increment of U.S. uranium enrichment capacity. The plant will use the gaseous diffusion process to provide the required capacity and reliability at a competitive enrichment services cost. Gaseous diffusion technology is the base against which other processes are compared in order to assess their commercial viability. While it has generally been described as a mature technology with limited future development potential, work on design of the new U.S. plant has resulted in major improvement in plant design with corresponding decreases in plant capacity and operating costs. The paper describes major technological advances incorporated into the new plant design and their impact on enrichment costs. These include the effects of: - advanced barrier technology; - tandem compressor drive systems; - optimization of number of equipment sizes; - single level plant design; - development of rapid power level change capability; - electrical system simplification; - plant arrangement and layout. Resulting capital costs and projected enrichment costs are summarized. Enrichment costs are placed in the context of total nuclear fuel cycle costs. Trade-offs between uranium feed material quantities and enrichment plant tails assays are described, and optimization of this aspect of the nuclear fuel cycle is discussed. The effect on enrichment plant characteristics is described. Flexibility and capability of the new U.S. enrichment plant to meet these changing optimization conditions are described

Evaluation of objects and food for environmental enrichment of NZW rabbits.

Science.gov (United States)

Harris, L D; Custer, L B; Soranaka, E T; Burge, J R; Ruble, G R

2001-01-01

The Guide for the Care and Use of Laboratory Animals states that both structural and social environments should be considered when addressing the husbandry needs of laboratory animals. The purpose of this study was to investigate environmental enrichment strategies that could potentially enhance the well-being of rabbits. Male and female 6-week old New Zealand White rabbits were divided into three groups: food-enriched (Bunny Stix, Bunny Blocks, or celery), non-food enriched (Jingle Ball, Kong toy, or Nylabone), and not enriched. Animals were given a particular enrichment for 1 h daily for 15 days. Home cages were fitted with specially designed plexiglass doors, which allowed the animals' interactions with the objects to be videotaped. The amount of time the animal interacted with each object and the total activity during the 1-h taped session were recorded for each rabbit. Rabbits were weighed weekly. Rabbits spent significantly more time interacting with the Bunny Stix than any other food item or non-food object. In addition, total activity time was significantly greater for all rabbits enriched with food versus any of the non-food items. Weight gains after 15 days did not differ significantly, but there was a trend towards increased weight gains in food-enriched rabbits. In this study, food was a stronger, more sustained enrichment device than were non-food objects.

CEO age and gender: Subsequent market performance

Directory of Open Access Journals (Sweden)

Marcelo Eduardo

2016-12-01

Full Text Available The issue of CEO age and gender vs. concurrent performance is extensively examined, but the association with subsequent performance has limited treatment in the financial literature, and with conflicting findings. In the current study, we examine the association between CEO age and gender, and subsequent company market performance using a more recent set of observations and the standard four-factor model to estimate future cumulative abnormal shareholder returns. We find that subsequent abnormal shareholder returns are marginally significantly higher for female CEOs than for their male counterparts, but no material pattern is observed between CEO age and subsequent abnormal shareholder return performance.

Effects of environmental enrichment on behaviour, physiology and performance of pigs: A review.

Science.gov (United States)

Mkwanazi, Mbusiseni Vusumuzi; Ncobela, Cyprial Ndumiso; Kanengoni, Arnold Tapera; Chimonyo, Michael

2017-06-26

The aim of this paper is to critically analyse and synthesise existing knowledge concerning the use of environmental enrichment and its effect on behaviour, physiology and performance of pigs housed in intensive production systems. The objective is also to provide clarity as to what constitute successful enrichment and recommend on when and how enrichment should be used. Environmental enrichment is usually understood as an attempt to improve animal welfare and to lesser extent, performance. Common enrichment objects used are straw bedding, suspended rope and wood shavings, toys, rubber tubing, coloured plastic keys, table tennis balls, chains and strings. These substrates need to be chewable, deformable, destructible and ingestible. For enrichment to be successful four goals are the prerequisite. Firstly, enrichment should increase the number and range of normal behaviours (2) prevent the phenomenon of anomalous behaviours or reduce their frequency (3) increase positive use of the environment such as space and (4) increase the ability of the animals to deal with behavioural and physiological challenges. The performance, behaviour and physiology of pigs in enriched environments is similar or in some cases slightly better when compared with barren environments. In studies where there was no improvement, it should be born in mind that enriching the environment may not always be practical and yield positive results due to factors such as type of enrichment substrates, duration of provision and type of enrichment used. The review also identifies possible areas which still need further research, especially in understanding the role of enrichment, novelty, breed differences and other enrichment alternatives.

Some economic aspects of the low enriched uranium production

International Nuclear Information System (INIS)

1990-05-01

At the Technical Committee Meeting on Economics of Low Enriched Uranium 14 papers were presented. A separate abstract was prepared for each of these papers. The five technical sessions covered several economic aspects of uranium concentrates production, conversion into uranium hexafluoride and uranium enrichment and the recycling of U and Pu in LWR. Four Panel discussions were held to discuss the uranium market trends, the situation of conversion industry, the reprocessing and the uranium market, the future trends of enrichment and the economics of LWRs compared with other reactors. Refs, figs and tabs

A Resolution of the Paradox of Enrichment

OpenAIRE

Feng, Z. C.; Li, Y. Charles

2011-01-01

The paradox of enrichment was observed by M. Rosenzweig in a class of predator-prey models. Two of the parameters in the models are crucial for the paradox. These two parameters are the prey's carrying capacity and prey's half-saturation for predation. Intuitively, increasing the carrying capacity due to enrichment of the prey's environment should lead to a more stable predator-prey system. Analytically, it turns out that increasing the carrying capacity always leads to an unstable predator-p...

Uranium enrichment management review: summary of analysis

International Nuclear Information System (INIS)

1981-01-01

In May 1980, the Assistant Secretary for Resource Applications within the Department of Energy requested that a group of experienced business executives be assembled to review the operation, financing, and management of the uranium enrichment enterprise as a basis for advising the Secretary of Energy. After extensive investigation, analysis, and discussion, the review group presented its findings and recommendations in a report on December 2, 1980. The following pages contain background material on which that final report was based. This report is arranged in chapters that parallel those of the uranium enrichment management review final report - chapters that contain summaries of the review group's discussion and analyses in six areas: management of operations and construction; long-range planning; marketing of enrichment services; financial management; research and development; and general management. Further information, in-depth analysis, and discussion of suggested alternative management practices are provided in five appendices

Uranium enrichment management review: summary of analysis

Energy Technology Data Exchange (ETDEWEB)

1981-01-01

In May 1980, the Assistant Secretary for Resource Applications within the Department of Energy requested that a group of experienced business executives be assembled to review the operation, financing, and management of the uranium enrichment enterprise as a basis for advising the Secretary of Energy. After extensive investigation, analysis, and discussion, the review group presented its findings and recommendations in a report on December 2, 1980. The following pages contain background material on which that final report was based. This report is arranged in chapters that parallel those of the uranium enrichment management review final report - chapters that contain summaries of the review group's discussion and analyses in six areas: management of operations and construction; long-range planning; marketing of enrichment services; financial management; research and development; and general management. Further information, in-depth analysis, and discussion of suggested alternative management practices are provided in five appendices.

Method of deuterium isotope separation and enrichment

International Nuclear Information System (INIS)

Benson, S.W.

1980-01-01

A method of deuterium isotope separation and enrichment using infrared laser technology in combination with chemical processes for treating and recycling the unreacted and deuterium-depleted starting materials is described. Organic molecules of the formula RX (where R is an ethyl, isopropyl, t-butyl, or cyclopentenyl group and X is F, Cl, Br or OH) containing a normal abundance of hydrogen and deuterium are exposed to intense laser infrared radiation. An olefin containing deuterium (olefin D) will be formed, along with HX. The enriched olefin D can be stripped from the depleted stream of RX and HX, and can be burned to form enriched water or pyrolyzed to produce hydrogen gas with elevated deuterium content. The depleted RX is decomposed to olefins and RX, catalytically exchanged with normal water to restore the deuterium content to natural levels, and recombined to form RX which can be recycled. (LL)

[Hydroxylamine conversion by anammox enrichment].

Science.gov (United States)

Hu, Anhui; Zheng, Ping; Lu, Huifeng; Ding, Shuang; Wang, Caihua

2010-04-01

Hydroxylamine is an important intermediate product of anammox. This study was focused on the characteristics of hydroxylamine and nitrite conversions by anammox enrichment. The changes of nitrogenous substrates and related products with time were measured using batch tests with anammox enrichment as inoculum. Since hydroxylamine didn't react with nitrite in uninoculated control culture, these two compounds were chemically stable. Both of them decreased with time in anammox enrichment inoculated cultures, in which ammonia as intermediate product would be produced and converted with the maximum concentration being 0.338 mg/L. The total nitrogen concentration decreased from 4.694 mmol/L to 0.812 mmol/L with conversion rate 82.7% in the end. When hydroxylamine and nitrite concentrations were about 2.5 mmol/L respectively, the maximum specific sludge conversion rates of hydroxylamine was 0.535 mmol/(gVSS.h), which was 1.81 times bigger than that of ammonia in ammonia reaction system; the maximum specific sludge rate of total nitrogen was slightly higher than that in ammonia reaction system. When hydroxylamine concentration increased to 5.0 mmol/L, the hydroxylamine and nitrite conversion rates promoted by 26.7% and 120.7% respectively; and the maximum ammonia accumulated was 1.810 mmol/L. When nitrite concentration increased to 5.0 mmol/L, the hydroxylamine and nitrite conversion rates promoted by 6.9% and 9.0% respectively; and the maximum ammonia accumulated was 0.795 mmol/L. Anammox enrichment was capable of converting hydroxylamine and nitrite simultaneously and had the higher conversion rate of hydroxylamine than ammonia conversion rate. Hydroxylamine and nitrite conversion rates were less affected by increase in nitrite concentration, but more significantly influenced by increase in hydroxylamine. The maximum ammonia concentration accumulated would rise as the result of increasing both hydroxylamine and nitrite. The result of experiment was consistent with pathway

10 CFR 70.23a - Hearing required for uranium enrichment facility.

Science.gov (United States)

2010-01-01

... 10 Energy 2 2010-01-01 2010-01-01 false Hearing required for uranium enrichment facility. 70.23a... MATERIAL License Applications § 70.23a Hearing required for uranium enrichment facility. The Commission... license for construction and operation of a uranium enrichment facility. The Commission will publish...

Environmental Enrichment Mitigates Deficits after Repetitive Mild Traumatic Brain Injury.

Science.gov (United States)

Liu, Xixia; Qiu, Jianhua; Alcon, Sasha; Hashim, Jumana; Meehan, William P; Mannix, Rebekah

2017-08-15

Although environmental enrichment has been shown to improve functional and histologic outcomes in pre-clinical moderate-to-severe traumatic brain injury (TBI), there are a paucity of pre-clinical data regarding enrichment strategies in the setting of repetitive mild traumatic brain injury (rmTBI). Given the vast numbers of athletes and those in the military who sustain rmTBI, the mounting evidence of the long-term and progressive sequelae of rmTBI, and the lack of targeted therapies to mitigate these sequelae, successful enrichment interventions in rmTBI could have large public health significance. Here, we evaluated enrichment strategies in an established pre-clinical rmTBI model. Seventy-one male C57BL/6 mice were randomized to two different housing conditions, environmental enrichment (EE) or normal condition (NC), then subjected to rmTBI injury (seven injuries in 9 days) or sham injury (anesthesia only). Functional outcomes in all four groups (NC-TBI, EE-TBI, NC-sham, and EE-sham) were assessed by motor, exploratory/anxiety, and mnemonic behavioral tests. At the synaptic level, N-methyl d-aspartate receptor (NMDAR) subunit expression of phosphorylated glutamate receptor 1 (GluR1), phosphorylated Ca 2+ /calmodulin-dependent protein kinase II (CaMKII), and calpain were evaluated by western blot. Compared to injured NC-TBI mice, EE-TBI mice had improved memory and decreased anxiety and exploratory activity post-injury. Treatment with enrichment also corresponded to normal NMDAR subunit expression, decreased GluR1 phosphorylation, decreased phosphorylated CaMKII, and normal calpain expression post-rmTBI. These data suggest that enrichment strategies may improve functional outcomes and mitigate synaptic changes post-rmTBI. Given that enrichment strategies are feasible in the clinical setting, particularly for athletes and soldiers for whom the risk of repetitive injury is greatest, these data suggest that clinical trials may be warranted.

Improved enrichment culture technique for methane-oxidizing bacteria from marine ecosystems: the effect of adhesion material and gas composition.

Science.gov (United States)

Vekeman, Bram; Dumolin, Charles; De Vos, Paul; Heylen, Kim

2017-02-01

Cultivation of microbial representatives of specific functional guilds from environmental samples depends largely on the suitability of the applied growth conditions. Especially the cultivation of marine methanotrophs has received little attention, resulting in only a limited number of ex situ cultures available. In this study we investigated the effect of adhesion material and headspace composition on the methane oxidation activity in methanotrophic enrichments obtained from marine sediment. Addition of sterilized natural sediment or alternatively the addition of acid-washed silicon dioxide significantly increased methane oxidation. This positive effect was attributed to bacterial adhesion on the particles via extracellular compounds, with a minimum amount of particles required for effect. As a result, the particles were immobilized, thus creating a stratified environment in which a limited diffusive gas gradients could build up and various microniches were formed. Such diffusive gas gradient might necessitate high headspace concentrations of CH 4 and CO 2 for sufficient concentrations to reach the methane-oxidizing bacteria in the enrichment culture technique. Therefore, high concentrations of methane and carbon dioxide, in addition to the addition of adhesion material, were tested and indeed further stimulated methane oxidation. Use of adhesion material in combination with high concentrations of methane and carbon dioxide might thus facilitate the cultivation and subsequent enrichment of environmentally important members of this functional guild. The exact mechanism of the observed positive effects on methane oxidation and the differential effect on methanotrophic diversity still needs to be explored.

Effect of Listeria seeligeri or Listeria welshimeri on Listeria monocytogenes detection in and recovery from buffered Listeria enrichment broth.

Science.gov (United States)

Dailey, Rachel C; Welch, Lacinda J; Hitchins, Anthony D; Smiley, R Derike

2015-04-01

The presence of multiple species of Listeria in regulated food products is not uncommon and can complicate the recovery of Listeria monocytogenes particularly on a non-differentiating medium. The potential complications of Listeria seeligeri and Listeria welshimeri on the recovery of L. monocytogenes from inoculated food test samples using the U.S. Food and Drug Administration's (FDA) selective enrichment procedure was investigated. Post-enrichment enumeration, in the absence of food product, indicates that some L. seeligeri and L. monocytogenes pairings may have population differentials as great as 2.7 ± 0.1 logs with L. seeligeri being the predominant species. A similar observation was noted for L. welshimeri and L. monocytogenes pairings which resulted in population differentials as large as 3.7 ± 0.2 logs with L. welshimeri being the predominant species. Select strain pairings were used to inoculate guacamole, crab meat, broccoli, and cheese with subsequent recovery by the FDA Bacteriological Analytical Manual (BAM) method with 10 colonies per sample selected for confirmation. The presence of L. seeligeri had little effect on the recovery of L. monocytogenes. The presence of L. welshimeri resulted in the failure to recover L. monocytogenes in three out of the four food matrices. This work extends the observation that non-pathogenic species of Listeria can complicate the recovery of L. monocytogenes and that competition during selective enrichment is not limited to the presence of just Listeria innocua. Published by Elsevier Ltd.

Effect of Listeria seeligeri or Listeria welshimeri on Listeria monocytogenes detection in and recovery from buffered Listeria enrichment broth☆

Science.gov (United States)

Dailey, Rachel C.; Welch, Lacinda J.; Hitchins, Anthony D.; Smiley, R. Derike

2016-01-01

The presence of multiple species of Listeria in regulated food products is not uncommon and can complicate the recovery of Listeria monocytogenes particularly on a non-differentiating medium. The potential complications of Listeria seeligeri and Listeria welshimeri on the recovery of L. monocytogenes from inoculated food test samples using the U.S. Food and Drug Administration's (FDA) selective enrichment procedure was investigated. Post-enrichment enumeration, in the absence of food product, indicates that some L. seeligeri and L. monocytogenes pairings may have population differentials as great as 2.7 ± 0.1 logs with L. seeligeri being the predominant species. A similar observation was noted for L. welshimeri and L. monocytogenes pairings which resulted in population differentials as large as 3.7 ± 0.2 logs with L. welshimeri being the predominant species. Select strain pairings were used to inoculate guacamole, crab meat, broccoli, and cheese with subsequent recovery by the FDA Bacteriological Analytical Manual (BAM) method with 10 colonies per sample selected for confirmation. The presence of L. seeligeri had little effect on the recovery of L. monocytogenes. The presence of L. welshimeri resulted in the failure to recover L. monocytogenes in three out of the four food matrices. This work extends the observation that non-pathogenic species of Listeria can complicate the recovery of L. monocytogenes and that competition during selective enrichment is not limited to the presence of just Listeria innocua. PMID:25475325

Can enrichment make Brazilian tapir spend more time on view to the public?

Science.gov (United States)

Dutra, Luísa Mascarenhas Ladeia; Young, Robert John

2015-01-01

One common visitor complaint in zoos is that the nonhuman animals are not visible. This problem needs to be resolved without compromising the animals' welfare; environmental enrichment could solve the problem. This study investigated whether enrichment would increase public exposure time of lowland tapir (Tapirus terrestris) in the Belo Horizonte Zoo in Minas Gerais, Brazil. Observations were made before (62 hr) and during (62 hr) the introduction of enrichment using focal animal sampling with instantaneous recording of behavior. The 5 enrichment items were a bamboo fence covered in vines, logs, a sandbox, dry leaves, and bamboo bushes. Before the enrichments were applied, the tapir was not visible to the public for more than 85% of the time. In addition, during the analysis of the enrichment treatment, other variables were considered--such as weekday, time of day, and weather conditions--which could influence the animals' interaction with the enrichments. The enrichments increased and decreased the expression of some behaviors; however, public viewing time of the animals did not increase. Thus, the enrichment applied was not strong enough to overcome the animals' crepuscular behavior.

Improved verification methods for safeguards verifications at enrichment plants

International Nuclear Information System (INIS)

Lebrun, A.; Kane, S. C.; Bourva, L.; Poirier, S.; Loghin, N. E.; Langlands, D.

2009-01-01

The International Atomic Energy Agency (IAEA) has initiated a coordinated research and development programme to improve its verification methods and equipment applicable to enrichment plants. The programme entails several individual projects to meet the objectives of the IAEA Safeguards Model Approach for Gas Centrifuge Enrichment Plants updated in 2006. Upgrades of verification methods to confirm the absence of HEU (highly enriched uranium) production have been initiated and, in particular, the Cascade Header Enrichment Monitor (CHEM) has been redesigned to reduce its weight and incorporate an electrically cooled germanium detector. Such detectors are also introduced to improve the attended verification of UF 6 cylinders for the verification of the material balance. Data sharing of authenticated operator weighing systems such as accountancy scales and process load cells is also investigated as a cost efficient and an effective safeguards measure combined with unannounced inspections, surveillance and non-destructive assay (NDA) measurement. (authors)

Conversion of research reactors to low-enrichment uranium fuels

International Nuclear Information System (INIS)

Muranaka, R.G.

1983-01-01

There are at present approximately 350 research reactors in 52 countries ranging in power from less than 1 watt to 100 Megawatt and over. In the 1970's, many people became concerned about the possibility that some fuels and fuel cycles could provide an easy route to the acquisition of nuclear weapons. Since enrichment to less than 20% is internationally recognized as a fully adequate barrier to weapons usability, certain Member States have moved to minimize the international trade in highly enriched uranium and have established programmes to develop the technical means to help convert research reactors to the use of low-enrichment fuels with minimum penalties. This could involve modifications in the design of the reactor and development of new fuels. As a result of these programmes, it is expected that most research reactors can be converted to the use of low-enriched fuel

Improved verification methods for safeguards verifications at enrichment plants

Energy Technology Data Exchange (ETDEWEB)

Lebrun, A.; Kane, S. C.; Bourva, L.; Poirier, S.; Loghin, N. E.; Langlands, D. [Department of Safeguards, International Atomic Energy Agency, Wagramer Strasse 5, A1400 Vienna (Austria)

2009-07-01

The International Atomic Energy Agency (IAEA) has initiated a coordinated research and development programme to improve its verification methods and equipment applicable to enrichment plants. The programme entails several individual projects to meet the objectives of the IAEA Safeguards Model Approach for Gas Centrifuge Enrichment Plants updated in 2006. Upgrades of verification methods to confirm the absence of HEU (highly enriched uranium) production have been initiated and, in particular, the Cascade Header Enrichment Monitor (CHEM) has been redesigned to reduce its weight and incorporate an electrically cooled germanium detector. Such detectors are also introduced to improve the attended verification of UF{sub 6} cylinders for the verification of the material balance. Data sharing of authenticated operator weighing systems such as accountancy scales and process load cells is also investigated as a cost efficient and an effective safeguards measure combined with unannounced inspections, surveillance and non-destructive assay (NDA) measurement. (authors)

Centrifuge enrichment plants. (Latest citations from the NTIS bibliographic database). Published Search

International Nuclear Information System (INIS)

1993-09-01

The bibliography contains citations concerning the design, control, monitoring, and safety of centrifuge enrichment plants. Power supplies, enrichment plant safeguards, facility design, cascade heater test loops to monitor the enrichment process, inspection strategies, and the socioeconomic effects of centrifuge enrichment plants are examined. Radioactive waste disposal problems are considered. (Contains a minimum of 171 citations and includes a subject term index and title list.)

Availability of enriched isotopic material for accelerator targets

International Nuclear Information System (INIS)

Newman, E.

1982-01-01

The electromagnetic isotope enrichment facility at ORNL provides a broad spectrum of highly enriched stable isotopes to the worldwide scientific community. The continued timely availability of these materials is of vital importance in many areas of basic research and, in particular, as source material for the fabrication of accelerator targets. A brief description of the facility and its capabilities and limitations is presented

Modeling of Transients in an Enrichment Circuit

International Nuclear Information System (INIS)

Fernandino, Maria; Delmastro, Dario; Brasnarof, Daniel

2003-01-01

In the present work a mathematical model is presented in order to describe the dynamic behavior inside a closed enrichment loop, the latter representing a single stage of an uranium gaseous diffusion enrichment cascade.The analytical model is turned into a numerical model, and implemented through a computational code.Transients of two species separation were numerically analyzed, including setting times of each magnitude, behavior of each one of them during different transients, and redistribution of concentrations along the closed loop

Qualification status of LEU [low enriched uranium] fuels

International Nuclear Information System (INIS)

Snelgrove, J.L.

1987-01-01

Sufficient data has been obtained from tests of high-density, low-enriched fuels for research and test reactors to declare them qualified for use. These fuels include UZrH x (TRIGA fuel) and UO 2 (SPERT fuel) for rod-type reactors and UAl x , U 3 O 8 , U 3 Si 2 , and U 3 Si dispersed in aluminium for plate-type reactors. Except for U 3 Si, the allowable fission density for LEU applications is limited only by the available 235 U. Several reactors are now using these fuels, and additional conversions are in progress. The basic performance characteristics and limits, if any, of the qualified low-enriched (and medium-enriched) fuels are discussed. Continuing and planned work to qualify additional fuels is also discussed. (Author)

Environmental enrichment delays pup-induced maternal behavior in rats.

Science.gov (United States)

Mann, Phyllis E; Gervais, Kristen J

2011-05-01

Adult, virgin rats do not spontaneously display maternal behavior when exposed to foster pups. However, continuous daily exposure of the female to foster pups for about 5-7 days can induce a set of maternal behaviors similar to those shown by postpartum dams. Induction latencies depend upon a number of factors, including the stress and anxiety levels of the female. The goal of this study was to attempt to mitigate the likely stressfulness of being singly housed during testing by enriching the rat's home cage environment and to determine if the concomitant environmental change would alter the latency to express maternal behavior. In addition, the effect of varying the number of test pups used for testing was examined. Two groups of virgin Sprague-Dawley rats were first tested on the elevated plus maze after 1 week of exposure to either control (standard housing) or enriched conditions. One week later, maternal behavior testing began using one or three pups. Upon completion of maternal behavior testing, plasma corticosterone concentrations were determined following a mild stressor. The data indicate that enrichment tends to increase anxiety-like behaviors in the elevated plus maze. In addition, enrichment delayed the onset of maternal behavior irrespective of the number of test pups. There were no effects of environmental enrichment on plasma corticosterone levels following exposure to a stressor. These results indicate that what is considered a modestly enriched environment delays the expression of pup-oriented responses and does not apparently reduce stress or improve performance on all behavioral tasks. Copyright © 2011 Wiley Periodicals, Inc.

Evaluation of Methyl-Binding Domain Based Enrichment Approaches Revisited.

Directory of Open Access Journals (Sweden)

Karolina A Aberg

Full Text Available Methyl-binding domain (MBD enrichment followed by deep sequencing (MBD-seq, is a robust and cost efficient approach for methylome-wide association studies (MWAS. MBD-seq has been demonstrated to be capable of identifying differentially methylated regions, detecting previously reported robust associations and producing findings that replicate with other technologies such as targeted pyrosequencing of bisulfite converted DNA. There are several kits commercially available that can be used for MBD enrichment. Our previous work has involved MethylMiner (Life Technologies, Foster City, CA, USA that we chose after careful investigation of its properties. However, in a recent evaluation of five commercially available MBD-enrichment kits the performance of the MethylMiner was deemed poor. Given our positive experience with MethylMiner, we were surprised by this report. In an attempt to reproduce these findings we here have performed a direct comparison of MethylMiner with MethylCap (Diagenode Inc, Denville, NJ, USA, the best performing kit in that study. We find that both MethylMiner and MethylCap are two well performing MBD-enrichment kits. However, MethylMiner shows somewhat better enrichment efficiency and lower levels of background "noise". In addition, for the purpose of MWAS where we want to investigate the majority of CpGs, we find MethylMiner to be superior as it allows tailoring the enrichment to the regions where most CpGs are located. Using targeted bisulfite sequencing we confirmed that sites where methylation was detected by either MethylMiner or by MethylCap indeed were methylated.

Wildland fire limits subsequent fire occurrence

Science.gov (United States)

Sean A. Parks; Carol Miller; Lisa M. Holsinger; Scott Baggett; Benjamin J. Bird

2016-01-01

Several aspects of wildland fire are moderated by site- and landscape-level vegetation changes caused by previous fire, thereby creating a dynamic where one fire exerts a regulatory control on subsequent fire. For example, wildland fire has been shown to regulate the size and severity of subsequent fire. However, wildland fire has the potential to influence...

Phosphopeptide Enrichment by Covalent Chromatography after Derivatization of Protein Digests Immobilized on Reversed-Phase Supports

Science.gov (United States)

Nika, Heinz; Nieves, Edward; Hawke, David H.; Angeletti, Ruth Hogue

2013-01-01

A rugged sample-preparation method for comprehensive affinity enrichment of phosphopeptides from protein digests has been developed. The method uses a series of chemical reactions to incorporate efficiently and specifically a thiol-functionalized affinity tag into the analyte by barium hydroxide catalyzed β-elimination with Michael addition using 2-aminoethanethiol as nucleophile and subsequent thiolation of the resulting amino group with sulfosuccinimidyl-2-(biotinamido) ethyl-1,3-dithiopropionate. Gentle oxidation of cysteine residues, followed by acetylation of α- and ε-amino groups before these reactions, ensured selectivity of reversible capture of the modified phosphopeptides by covalent chromatography on activated thiol sepharose. The use of C18 reversed-phase supports as a miniaturized reaction bed facilitated optimization of the individual modification steps for throughput and completeness of derivatization. Reagents were exchanged directly on the supports, eliminating sample transfer between the reaction steps and thus, allowing the immobilized analyte to be carried through the multistep reaction scheme with minimal sample loss. The use of this sample-preparation method for phosphopeptide enrichment was demonstrated with low-level amounts of in-gel-digested protein. As applied to tryptic digests of α-S1- and β-casein, the method enabled the enrichment and detection of the phosphorylated peptides contained in the mixture, including the tetraphosphorylated species of β-casein, which has escaped chemical procedures reported previously. The isolates proved highly suitable for mapping the sites of phosphorylation by collisionally induced dissociation. β-Elimination, with consecutive Michael addition, expanded the use of the solid-phase-based enrichment strategy to phosphothreonyl peptides and to phosphoseryl/phosphothreonyl peptides derived from proline-directed kinase substrates and to their O-sulfono- and O-linked β-N-acetylglucosamine (O

Low-enriched research reactor fuel: Post-Irradiation Examinations at SCK-CEN

International Nuclear Information System (INIS)

Van den Berghe, S.; Leenaers, A.

2007-01-01

Generally, research and test reactors are fuelled with fuel plates instead of pins. In most cases in the past, these plates consisted of high enriched (higher than 95 percent 235 U) UAl 3 powder mixed with a pure Al matrix (called the meat) in between two aluminium alloy plates (the cladding). These plates are then assembled in fuel elements of different designs to fit the needs of the various reactors. Since the 1970's, efforts have been going on to replace the high-enriched, low-density UAl 3 fuel with high-density, low enriched ( 235 U) replacements. This search is driven by the attempt to reduce the civil use of high-enriched materials because of proliferation risks and terrorist threats. American initiatives, such as the Global Threat Reduction Initiative and the Reduced Enrichment for Research and Test Reactors program have triggered the development of reliable low-enriched fuel types for these reactors, which can replace the high enriched ones without loss of performance. Most success has been obtained with U 3 Si 2 fuel, which is currently used in many research reactors in the world. However, efforts to search for a better replacement have continued and are currently directed towards the U-Mo alloy fuel (7-10 weight percent Mo)

The Schoolwide Enrichment Model: A Focus on Student Strengths and Interests

Science.gov (United States)

Renzulli, Joseph S.; Renzulli, Sally Reis

2010-01-01

This article includes an introduction to the Schoolwide Enrichment Model (SEM), with its three components: a total talent portfolio for each child, curriculum differentiation and modification, and enrichment opportunities from the Enrichment Triad Model. Also included is a brief history of the SEM and a summary of 30 years of research underlying…

Adoption of Enriched Local Complementary Food in Osun State ...

African Journals Online (AJOL)

Locally processed complementary foods, appropriately enriched can complement breast milk and traditional foods during the nutritionally vulnerable periods of a child life. The study therefore examines the adoption of enriched local complementary foods in Osun State Nigeria. Structured interview schedule was used to ...

Method for the preparation of deuterium-enriched water in the preparation of hydrogen

International Nuclear Information System (INIS)

Mandrin, C.

1984-01-01

The synthesis-gas plant is operated in a number of successive operating periods such that during the first operating period an excess of fresh water is supplied to the synthesis gas plant and the waste water from the resulting mixture is separated in a condenser and supplied to a storage container. During the subsequent operating periods, the waste water stored in the container is used as the feed water for the synthesis gas plant and the waste water obtained on each occasion is stored in the container with increasing deuterium concentration. The waste water obtained during the last operating period and having the highest deuterium concentration is used to feed a plant for producing heavy water. This process, when used in a synthesis gas plant for producing hydrogen, can be used to obtain deuterium-enriched water as a feedstock for a heavy-water plant without expensive additional energy-consuming devices

Tellurium Enrichment in Jurassic Coal, Brora, Scotland

Directory of Open Access Journals (Sweden)

Liam Bullock

2017-11-01

Full Text Available Mid-Jurassic pyritic coals exposed at the village of Brora, northern Scotland, UK, contain a marked enrichment of tellurium (Te relative to crustal mean, average world coal compositions and British Isles Carboniferous coals. The Te content of Brora coal pyrite is more than one order of magnitude higher than in sampled pyrite of Carboniferous coals. The Te enrichment coincides with selenium (Se and mercury (Hg enrichment in the rims of pyrite, and Se/Te is much lower than in pyrites of Carboniferous coals. Initial pyrite formation is attributed to early burial (syn-diagenesis, with incorporation of Te, Se, Hg and lead (Pb during later pyrite formation. The source of Te may have been a local hydrothermal system which was responsible for alluvial gold (Au in the region, with some Au in Brora headwaters occurring as tellurides. Anomalous Te is not ubiquitous in coal, but may occur locally, and is detectable by laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS.

NAA analysis of enriched Zn-68 by

International Nuclear Information System (INIS)

Rafii, H.; Mirzaei, M.; Mirzajani, N.; Sardari, D.; Shahabi, I.; Majedi, F.

2002-01-01

Excessive application of enriched isotopes in various fields of sciences and industry necessitates measuring their abundant by a precise and rapid methos. Beside the inductively coupled plasma mass spectrometry, the thermal neutron activation analysis, NAA, is an alternative method, which is capable to determine trace amounts of elements as well as the elemental abundance. In this article the enrichment of Zn-68 in two different samples has been studied by mean of NAA. One sample was separated by an electromagnetic system in our center and the other was purchased from a French company, Cortecnet. The neutron irradiation was took place in MNSR reactor by flux 10 1 1n/cm 2 sec. for 30 min. and the produced radioactivity from Zn-69 m was measured one day after irradiation by HPGe detector. The results shows a good agreement with the reported ones and its low derivation of about ±3.05 indicates that the NAA is a precise, rapid, and supplemental method for analyzing enriched Zn-68

Involvement of glycosphingolipid-enriched lipid rafts in inflammatory responses.

Science.gov (United States)

Iwabuchi, Kazuhisa

2015-01-01

Glycosphingolipids (GSLs) are membrane components consisting of hydrophobic ceramide and hydrophilic sugar moieties. GSLs cluster with cholesterol in cell membranes to form GSL-enriched lipid rafts. Biochemical analyses have demonstrated that GSL-enriched lipid rafts contain several kinds of transducer molecules, including Src family kinases. Among the GSLs, lactosylceramide (LacCer, CDw17) can bind to various microorganisms, is highly expressed on the plasma membranes of human phagocytes, and forms lipid rafts containing the Src family tyrosine kinase Lyn. LacCer-enriched lipid rafts mediate immunological and inflammatory reactions, including superoxide generation, chemotaxis, and non-opsonic phagocytosis. Therefore, LacCer-enriched membrane microdomains are thought to function as pattern recognition receptors (PRRs), which recognize pathogen-associated molecular patterns (PAMPs) expressed on microorganisms. LacCer also serves as a signal transduction molecule for functions mediated by CD11b/CD18-integrin (αM/β2-integrin, CR3, Mac-1), as well as being associated with several key cellular processes. LacCer recruits PCKα/ε and phospholipase A2 to stimulate PECAM-1 expression in human monocytes and their adhesion to endothelial cells, as well as regulating β1-integrin clustering and endocytosis on cell surfaces. This review describes the organizational and inflammation-related functions of LacCer-enriched lipid rafts.

Comparative study on gene set and pathway topology-based enrichment methods.

Science.gov (United States)

Bayerlová, Michaela; Jung, Klaus; Kramer, Frank; Klemm, Florian; Bleckmann, Annalen; Beißbarth, Tim

2015-10-22

Enrichment analysis is a popular approach to identify pathways or sets of genes which are significantly enriched in the context of differentially expressed genes. The traditional gene set enrichment approach considers a pathway as a simple gene list disregarding any knowledge of gene or protein interactions. In contrast, the new group of so called pathway topology-based methods integrates the topological structure of a pathway into the analysis. We comparatively investigated gene set and pathway topology-based enrichment approaches, considering three gene set and four topological methods. These methods were compared in two extensive simulation studies and on a benchmark of 36 real datasets, providing the same pathway input data for all methods. In the benchmark data analysis both types of methods showed a comparable ability to detect enriched pathways. The first simulation study was conducted with KEGG pathways, which showed considerable gene overlaps between each other. In this study with original KEGG pathways, none of the topology-based methods outperformed the gene set approach. Therefore, a second simulation study was performed on non-overlapping pathways created by unique gene IDs. Here, methods accounting for pathway topology reached higher accuracy than the gene set methods, however their sensitivity was lower. We conducted one of the first comprehensive comparative works on evaluating gene set against pathway topology-based enrichment methods. The topological methods showed better performance in the simulation scenarios with non-overlapping pathways, however, they were not conclusively better in the other scenarios. This suggests that simple gene set approach might be sufficient to detect an enriched pathway under realistic circumstances. Nevertheless, more extensive studies and further benchmark data are needed to systematically evaluate these methods and to assess what gain and cost pathway topology information introduces into enrichment analysis. Both

Beneficial effects of enriched environment following status epilepticus in immature rats.

Science.gov (United States)

Faverjon, S; Silveira, D C; Fu, D D; Cha, B H; Akman, C; Hu, Y; Holmes, G L

2002-11-12

There is increasing evidence that enriching the environment can improve cognitive and motor deficits following a variety of brain injuries. Whether environmental enrichment can improve cognitive impairment following status epilepticus (SE) is not known. To determine whether the environment in which animals are raised influences cognitive function in normal rats and rats subjected to SE. Rats (n = 100) underwent lithium-pilocarpine-induced SE at postnatal (P) day 20 and were then placed in either an enriched environment consisting of a large play area with toys, climbing objects, and music, or in standard vivarium cages for 30 days. Control rats (n = 32) were handled similarly to the SE rats but received saline injections instead of lithium-pilocarpine. Rats were then tested in the water maze, a measure of visual-spatial memory. A subset of the rats were killed during exposure to the enriched or nonenriched environment and the brains examined for dentate granule cell neurogenesis using bromodeoxyuridine (BrdU) and phosphorylated cyclic AMP response element binding protein (pCREB) immunostaining, a brain transcription factor important in long-term memory. Both control and SE rats exposed to the enriched environment performed significantly better than the nonenriched group in the water maze. There was a significant increase in neurogenesis and pCREB immunostaining in the dentate gyrus in both control and SE animals exposed to the enriched environment compared to the nonenriched groups. Environmental enrichment resulted in no change in SE-induced histologic damage. Exposure to an enriched environment in weanling rats significantly improves visual-spatial learning. Even following SE, an enriched environment enhances cognitive function. An increase in neurogenesis and activation of transcription factors may contribute to this enhanced visual-spatial memory.

Practical enrichment technique for 33S (34S)

International Nuclear Information System (INIS)

McInteer, B.B.; Lyman, J.L.; Nilsson, A.C.; Quigley, G.P.

1982-01-01

The successful preparation of a macroscopic sample of enriched 33 S by laser-induced molecular dissociation is reported. Approach was to induce isotopically selective dissociation of SF 6 with CO 2 -laser pulses and to separate the remaining SF 6 from the sulfur-containing reaction products by cryogenic distillation. A 200 Hz, 0.75 J/pulse laser was used for photolysis of low-pressure (less than 1 torr) gas mixtures. The mixture of SF 6 and scavenger recirculated continuously throughout the irradiation chamber where the laser pulses selectively dissociated 32 SF 6 to give the final products: SF 4 or SOF 2 . The unreacted SF 6 was enriched in the heavier isotopes: 33 S, 34 S, and 36 S. A 1.3-g sample of SF 6 was collected with a 33 S enrichment factor of 1.96 and a 34 S enrichment factor of 2.25. A similar size sample of depleted ( 32 S) sulfur compounds was also collected. A scavenger was necessary to ensure high yield, and moist hydrogen was found to be best for our conditions. Removal of hydrogen fluoride was also necessary to prevent severe corrosion and to maintain high isotopic selectivity. 6 figures

Uranium enrichment: a competitive market in the future?

Energy Technology Data Exchange (ETDEWEB)

Marques, Andre Ferreira; Honaiser, Eduardo Henrique Rangel [Centro Tecnologico da Marinha em Sao Paulo (CTMSP), Sao Paulo, SP (Brazil)]. E-mail: 20-1@ctemsp.mar.mil.br

2005-07-01

Uranium enrichment is the costly step in the nuclear fuel cycle. It has born as a an activity for the military in the 40s, financed by governments, such as the United States (US) and the former Soviet Union. Later, other major nations have joined them in the nuclear weapons development. The activity of enrichment was done in each country that developed nuclear weapons, and the nuclear weapons countries, especially the US and Soviet Union, dictated the mined uranium market. In the 70s, with the growth of the commercial use of nuclear energy, uranium enrichment started to be treated as a market, which gradually have structured itself, strongly influenced by the historical background. Today, the market is an oligopoly of four major government-owned (or government-influenced) companies. In this paper, the trends in the enrichment market are identified, focusing on competitiveness. Through the conduction of a market analysis (past and future), and the study of the market structure evolution, a more competitive market is shown, but still influenced by the governmental participation. Competitiveness is dictated by government support, verticalization capacity, and, mainly by technological advantages. (author)

Uranium enrichment: a competitive market in the future?

International Nuclear Information System (INIS)

Marques, Andre Ferreira; Honaiser, Eduardo Henrique Rangel

2005-01-01

Uranium enrichment is the costly step in the nuclear fuel cycle. It has born as a an activity for the military in the 40s, financed by governments, such as the United States (US) and the former Soviet Union. Later, other major nations have joined them in the nuclear weapons development. The activity of enrichment was done in each country that developed nuclear weapons, and the nuclear weapons countries, especially the US and Soviet Union, dictated the mined uranium market. In the 70s, with the growth of the commercial use of nuclear energy, uranium enrichment started to be treated as a market, which gradually have structured itself, strongly influenced by the historical background. Today, the market is an oligopoly of four major government-owned (or government-influenced) companies. In this paper, the trends in the enrichment market are identified, focusing on competitiveness. Through the conduction of a market analysis (past and future), and the study of the market structure evolution, a more competitive market is shown, but still influenced by the governmental participation. Competitiveness is dictated by government support, verticalization capacity, and, mainly by technological advantages. (author)

Phosphorylation of plant plasma membrane H+-ATPase by the heterologous host S. cerevisiae

DEFF Research Database (Denmark)

Rudashevskaya, Elena; Ye, Juanying; Young, Clifford

 It is known, that phosphorylation of both plant and yeast plasma membrane H+-ATPase results in enzyme activation or inhibition. Several sites at the regulatory C-terminus of the enzyme have been found to undergo phosphorylation in vivo in both plant and yeast. The C-termini of plant H...... of heterologous system of yeast cells, expressing plant proton pump. Therefore identification of possible regulatory effects by phosphorylation events in plant H+-ATPase in the system is significant. A number of putative phosphorylation sites at regulatory C-domain of H+-ATPase (AHA2) have been point...... functioning of the residues and suggests, that plant H+-ATPase could be regulated by phosphorylation at several sites being in yeast cells. Plant H+-ATPase purified from yeast cells by his-tag affinity chromatography was subjected to IMAC and TiO2 for enrichment of phosphopeptides. The phosphopeptides were...

Application of enriched stable isotopes as tracers in biological systems

DEFF Research Database (Denmark)

Stürup, Stefan; Hansen, Helle Rüsz; Gammelgaard, Bente

2008-01-01

The application of enriched stable isotopes of minerals and trace elements as tracers in biological systems is a rapidly growing research field that benefits from the many new developments in inorganic mass spectrometric instrumentation, primarily within inductively coupled plasma mass spectrometry...... (ICP-MS) instrumentation, such as reaction/collision cell ICP-MS and multicollector ICP-MS with improved isotope ratio measurement and interference removal capabilities. Adaptation and refinement of radioisotope tracer experiment methodologies for enriched stable isotope experiments......, and the development of new methodologies coupled with more advanced compartmental and mathematical models for the distribution of elements in living organisms has enabled a broader use of enriched stable isotope experiments in the biological sciences. This review discusses the current and future uses of enriched...

Safeguards for reprocessing and enrichment plants

International Nuclear Information System (INIS)

1977-01-01

Agency safeguards are entering a new phase with the coming under active safeguards for the first time of reprocessing plants in several regions of the world. This is taking place at a time when not only the safeguards aspect itself is coming under international scrutiny, but also at a time when the necessity of reprocessing plants is being called into question. Attracting less attention at the moment, but potentially of equal significance, are the enrichment plants that soon will be coming under Agency safeguards. It is not unreasonable in view of the present controversies to ask what is the significance of these reprocessing and enrichment plants, what are the problems concerning safeguards that appear to have given rise to the controversies, and how these problems are to be solved. The question of significance is an easy one to answer. The output of these plants is material which some people consider can be used directly for military purposes, whereas the output from other plants, for instance, reactors, would require long and extensive processing before it could be used for military purposes. Like most short answers, this one is an over-simplification which requires some elaboration to make it strictly accurate. For example, the material output of a power reactor is in the form of irradiate assemblies containing plutonium which is potentially of military use if the irradiation had been within a certain range. However, to utilize this plutonium under clandestine conditions, the highly radioactive material would have to be secretly transported to a reprocessing plant and there would have to be simultaneous falsification of the reactor material accounts and the plant records. Such falsification would be difficult to conceal. The total time required to obtain usable plutonium would be many months. Diversion of material from a uranium fabrication plant making fuel for power reactors would be easier physically but strategically it would be of little value. The

Factors that predict consumer acceptance of enriched processed meats.

Science.gov (United States)

Shan, Liran C; Henchion, Maeve; De Brún, Aoife; Murrin, Celine; Wall, Patrick G; Monahan, Frank J

2017-11-01

The study aimed to understand predictors of consumers' purchase intention towards processed meat based functional foods (i.e. enriched processed meat). A cross-sectional survey was conducted with 486 processed meat consumers in spring 2016. Results showed that processed meats were perceived differently in healthiness, with sausage-type products perceived less healthy than cured meat products. Consumers were in general more uncertain than positive about enriched processed meat but differences existed in terms of the attitudes and purchase intention. Following regression analysis, consumers' purchase intention towards enriched processed meat was primarily driven by their attitudes towards the product concept. Perceived healthiness of existing products and eating frequency of processed meat were also positively associated with the purchase intention. Other factors such as general food choice motives, socio-demographic characteristics, consumer health and the consumption of functional foods and dietary supplements in general, were not significant predictors of the purchase intention for enriched processed meat. Copyright © 2017 Elsevier Ltd. All rights reserved.

The antecedents and outcomes of work-family enrichment amongst female workers

Directory of Open Access Journals (Sweden)

Esandre Marais

2014-11-01

Research purpose: The objective was to determine the relationship between work resources,home resources, work engagement, family engagement and work-family enrichment. The aim was also to test two models representing work-to-family and family-to-work enrichment as mediators. Motivation for the study: By investigating work-family enrichment, as a new research concept,and its antecedents and outcomes, this study will add to the positive side of the work-family interface literature and provide information to organisations.Research design, approach and method: A cross-sectional survey design was used in this study with a sample of female workers (N = 420 in South Africa. Polychoric correlations, fit indices, structural equation modelling and testing mediation were used to analyse the data.Omegas and alpha coefficients were employed to determine the reliability. Main findings: A positive relationship between work-family enrichment and its antecedents and outcomes was found. Furthermore, work-family enrichment (W-FE mediated (large effectthe relationship between work resources and work engagement and family-work enrichment mediated (small effect the relationship between home resources and family engagement. Practical/managerial implications: The results provide more insight and understanding to organisations and female workers on the benefits of being involved in both the domain of work life and the domain of family life. Contribution/value-add: The study contributes to the limited research undertaken on work family enrichment within the South African context. The present study also contributes to the literature on the use of the newly developed MACE Work-Family Enrichment Instrument.

29 CFR 18.407 - Subsequent remedial measures.

Science.gov (United States)

2010-07-01

... OFFICE OF ADMINISTRATIVE LAW JUDGES Rules of Evidence Relevancy and Its Limits § 18.407 Subsequent... event less likely to occur, evidence of the subsequent measures is not admissible to prove negligence or...

Standard specification for uranium hexafluoride enriched to less than 5 % 235U

CERN Document Server

American Society for Testing and Materials. Philadelphia

2010-01-01

1.1 This specification covers nuclear grade uranium hexafluoride (UF6) that either has been processed through an enrichment plant, or has been produced by the blending of Highly Enriched Uranium with other uranium to obtain uranium of any 235U concentration below 5 % and that is intended for fuel fabrication. The objectives of this specification are twofold: (1) To define the impurity and uranium isotope limits for Enriched Commercial Grade UF6 so that, with respect to fuel design and manufacture, it is essentially equivalent to enriched uranium made from natural UF6; and (2) To define limits for Enriched Reprocessed UF6 to be expected if Reprocessed UF6 is to be enriched without dilution with Commercial Natural UF6. For such UF6, special provisions, not defined herein, may be needed to ensure fuel performance and to protect the work force, process equipment, and the environment. 1.2 This specification is intended to provide the nuclear industry with a standard for enriched UF6 that is to be used in the pro...

Feasibility of nondestructive assay measurements in uranium enrichment plants

Energy Technology Data Exchange (ETDEWEB)

Walton, R.B.

1978-04-01

Applications of nondestructive assay methods to measurement problems in uranium enrichment facilities are reviewed. The results of a number of test and evaluation projects that were performed over the last decade at ORGDP and Portsmouth are presented. Measurements of the residual holdup in the top enrichment portion of the shut-down K-25 cascade were made with portable neutron and gamma-ray detectors, and inventory estimates based on these data were in good agreement with ORGDP estimates. In the operating cascade, the tests showed that portable NaI detectors are effective for monitoring NaF and alumina media for gaseous effluent traps and that gas phase enrichments and inventories, as well as large deposits of uranium, can be detected with portable neutron and gamma-ray instrumentation. A wide variety of scrap and waste materials, including barrier and compressor blades, incinerator ash and trapping media, and miscellaneous waste, were measured using passive gamma-ray and neutron methods and 14-MeV neutron interrogation. Methods developed for rapid verification of UF/sub 6/ in shipping containers with portable neutron and gamma-ray instruments are now used routinely by safeguards inspectors. Passive assay methods can also be used to measure continuously the enrichments of /sup 235/U and /sup 234/U in the UF/sub 6/ product and tails withdrawals of a gaseous diffusion plant. A system that was developed and installed in the extended-range product withdrawal station of the Portsmouth facility measures enrichment with a relative accuracy of 0.5%. A stand-alone neutron detector has also been successfully evaluated for the measurement of the isotopic abundance of /sup 234/U in UF/sub 6/ in sample cylinders, an application of potential importance to Minor Isotope Safeguards Technology. Recommendations are made on the role of NDA measurements for enrichment plant safeguards, including additional tests and evaluations that may be needed, particularly for advanced uranium

Yalina booster subcritical assembly performance with low enriched uranium fuel

International Nuclear Information System (INIS)

Talamo, Alberto; Gohar, Yousry

2011-01-01

The YALINA Booster facility is a subcritical assembly located in Minsk, Belarus. The facility has special features that result in fast and thermal neutron spectra in different zones. The fast zone of the assembly uses a lead matrix and uranium fuels with different enrichments: 90% and 36%, 36%, or 21%. The thermal zone of the assembly contains 10% enriched uranium fuel in a polyethylene matrix. This study discusses the performance of the three YALINA Booster configurations with the different fuel enrichments. In order to maintain the same subcriticality level in the three configurations, the number of fuel rods in the thermal zone is increased as the uranium fuel enrichment in the fast zone is decreased. The maximum number of fuel rods that can be loaded in the thermal zone is about 1185. Consequently, the neutron multiplication of the configuration with 21% enriched uranium fuel in the fast zone is enhanced by changing the position of the boron carbide and the natural uranium absorber rods, located between the fast and the thermal zones, to form an annular rather than a square arrangement. (author)

Yalina booster subcritical assembly performance with low enriched uranium fuel

Energy Technology Data Exchange (ETDEWEB)

Talamo, Alberto; Gohar, Yousry, E-mail: alby@anl.gov [Argonne National Laboratory, Lemont, IL (United States)

2011-07-01

The YALINA Booster facility is a subcritical assembly located in Minsk, Belarus. The facility has special features that result in fast and thermal neutron spectra in different zones. The fast zone of the assembly uses a lead matrix and uranium fuels with different enrichments: 90% and 36%, 36%, or 21%. The thermal zone of the assembly contains 10% enriched uranium fuel in a polyethylene matrix. This study discusses the performance of the three YALINA Booster configurations with the different fuel enrichments. In order to maintain the same subcriticality level in the three configurations, the number of fuel rods in the thermal zone is increased as the uranium fuel enrichment in the fast zone is decreased. The maximum number of fuel rods that can be loaded in the thermal zone is about 1185. Consequently, the neutron multiplication of the configuration with 21% enriched uranium fuel in the fast zone is enhanced by changing the position of the boron carbide and the natural uranium absorber rods, located between the fast and the thermal zones, to form an annular rather than a square arrangement. (author)

Experiments of JRR-4 low-enriched-uranium-silicied fuel core

International Nuclear Information System (INIS)

Hirane, Nobuhiko; Ishikuro, Yasuhiro; Nagadomi, Hideki; Yokoo, Kenji; Horiguchi, Hironori; Nemoto, Takumi; Yamamoto, Kazuyoshi; Yagi, Masahiro; Arai, Nobuyoshi; Watanabe, Shukichi; Kashima, Yoichi

2006-03-01

JRR-4, a light-water-moderated and cooled, swimming pool type research reactor using high-enriched uranium plate-type fuels had been operated from 1965 to 1996. In order to convert to low-enriched-uranium-silicied fuels, modification work had been carried out for 2 years, from 1996 to 1998. After the modification, start-up experiments were carried out to obtain characteristics of the low-enriched-uranium-silicied fuel core. The measured excess reactivity, reactor shutdown margin and the maximum reactivity addition rate satisfied the nuclear limitation of the safety report for licensing. It was confirmed that conversion to low-enriched-uranium-silicied fuels was carried out properly. Besides, the necessary data for reactor operation were obtained, such as nuclear, thermal hydraulic and reactor control characteristics. This report describes the results of start-up experiments and burnup experiments. The first criticality of low-enriched-uranium-silicied core was achieved on 14th July 1998, and the operation for joint-use has been carried out since 6th October 1998. (author)

Effect of reduced enrichment on the fuel cycle for research reactors

International Nuclear Information System (INIS)

Travelli, A.

1982-01-01

The new fuels developed by the RERTR Program and by other international programs for application in research reactors with reduced uranium enrichment (<20% EU) are discussed. It is shown that these fuels, combined with proper fuel-element design and fuel-management strategies, can provide at least the same core residence time as high-enrichment fuels in current use, and can frequently significantly extend it. The effect of enrichment reduction on other components of the research reactor fuel cycle, such as uranium and enrichment requirements, fuel fabrication, fuel shipment, and reprocessing are also briefly discussed with their economic implications. From a systematic comparison of HEU and LEU cores for the same reference research reactor, it is concluded that the new fuels have a potential for reducing the research reactor fuel cycle costs while reducing, at the same time, the uranium enrichment of the fuel

Conversion and Blending Facility Highly enriched uranium to low enriched uranium as uranium hexafluoride. Revision 1

International Nuclear Information System (INIS)

1995-01-01

This report describes the Conversion and Blending Facility (CBF) which will have two missions: (1) convert surplus HEU materials to pure HEU UF 6 and a (2) blend the pure HEU UF 6 with diluent UF 6 to produce LWR grade LEU-UF 6 . The primary emphasis of this blending be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The chemical and isotopic concentrations of the blended LEU product will be held within the specifications required for LWR fuel. The blended LEU product will be offered to the United States Enrichment Corporation (USEC) to be sold as feed material to the commercial nuclear industry

Conversion and Blending Facility Highly enriched uranium to low enriched uranium as uranium hexafluoride. Revision 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-07-05

This report describes the Conversion and Blending Facility (CBF) which will have two missions: (1) convert surplus HEU materials to pure HEU UF{sub 6} and a (2) blend the pure HEU UF{sub 6} with diluent UF{sub 6} to produce LWR grade LEU-UF{sub 6}. The primary emphasis of this blending be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The chemical and isotopic concentrations of the blended LEU product will be held within the specifications required for LWR fuel. The blended LEU product will be offered to the United States Enrichment Corporation (USEC) to be sold as feed material to the commercial nuclear industry.

Laser enrichment: a new path to proliferation

International Nuclear Information System (INIS)

Casper, B.M.

1977-01-01

The use of lasers to obtain enriched uranium is an easier and cheaper method than methods currently in use. The immediate concern is that it could promote easy access to nuclear weapons by countries that do not presently have them. Mr. Casper feels that the U.S. government is working against itself; while the State Department is seeking to block one path to proliferation, ERDA laboratories are developing new technology that could open another. The proliferation implications have not been factored in a serious way into the decisions to proceed with this research. It is also clear that the United States does not now have a comprehensive policy that deals with all potentially important paths to proliferation, including laser enrichment. Mr. Casper states that there is still time to stop and consider whether laser enrichment should be developed, in light of its broader consequences. But this will not happen if the decisions are left exclusively in the hands of those promoting the technology, the author says. It is just this sort of situation that prompted the creation of several government institutions to provide independent assessments of new technologies. The Office of Technology Assessment, the Nuclear Regulatory Commission, and the Arms Control and Disarmament Agency all have the authority to intervene. Laser enrichment provides a good test of these institutions and of the viability of the concept of technology assessment. The status, benefits and risks, and the policy needed on laser research are discussed

The uranium enrichment market and long-term technological options

International Nuclear Information System (INIS)

Schneider-Maunoury, A.

1992-01-01

The world enrichment market situation is clearly delineated up to the year 2000. Including the East European countries, worldwide enriched uranium requirements should reach 40 million separative work units (SWUs) a year and production capacity should reach 44 millions SWUs. Two-thirds of this capacity will be supplied by the gaseous diffusion process and one-third by the centrifuge process. The enrichment processes currently considered are: (i) the gaseous diffusion process, (ii) the centrifuge process, (iii) the chemical treatment process and (iv) the laser processes, long-term assessment of the enrichment market up to the year 2015. Two scenarios may be envisioned for the (i) Public opinion will continue to block the development of nuclear power, and requirements will level off at 40 million SWUs. (ii) Changing attitudes will favor a reasonable approach enabling a revival of nuclear power expansion around 1995. Requirements should then increase starting in 2005 and would readily attain 60 million SWUs a year by 2015. Depending on market conditions, enrichment process options will be influenced either entirely by cost considerations, without allowance for the time factor, or by need to meet demand. Demonstrations of the industrial validity of laser processes are expected by 1992 - 1995 and, if interest in nuclear power makes a comeback, decisions should be made between 1995 and 2000 to build new large-capacity enrichment plants. The gaseous diffusion process may still be used for a long time if nuclear power is judiciously employed. The centrifuge process will be fully mature by the year 2000. The uranium vapor laser processes offer the most promise and should ultimately prevail. the chemical processes, though outsiders, deserve watching. (author)

Short-term blueberry-enriched diet prevents and reverses object recognition memory loss in aging rats.

Science.gov (United States)

Malin, David H; Lee, David R; Goyarzu, Pilar; Chang, Yu-Hsuan; Ennis, Lalanya J; Beckett, Elizabeth; Shukitt-Hale, Barbara; Joseph, James A

2011-03-01

Previously, 4 mo of a blueberry-enriched (BB) antioxidant diet prevented impaired object recognition memory in aging rats. Experiment 1 determined whether 1- and 2-mo BB diets would have a similar effect and whether the benefits would disappear promptly after terminating the diets. Experiment 2 determined whether a 1-mo BB diet could subsequently reverse existing object memory impairment in aging rats. In experiment 1, Fischer-344 rats were maintained on an appropriate control diet or on 1 or 2 mo of the BB diet before testing object memory at 19 mo postnatally. In experiment 2, rats were tested for object recognition memory at 19 mo and again at 20 mo after 1 mo of maintenance on a 2% BB or control diet. In experiment 1, the control group performed no better than chance, whereas the 1- and 2-mo BB diet groups performed similarly and significantly better than controls. The 2-mo BB-diet group, but not the 1-mo group, maintained its performance over a subsequent month on a standard laboratory diet. In experiment 2, the 19-mo-old rats performed near chance. At 20 mo of age, the rats subsequently maintained on the BB diet significantly increased their object memory scores, whereas the control diet group exhibited a non-significant decline. The change in object memory scores differed significantly between the two diet groups. These results suggest that a considerable degree of age-related object memory decline can be prevented and reversed by brief maintenance on BB diets. Copyright © 2011 Elsevier Inc. All rights reserved.

Conversion and Blending Facility highly enriched uranium to low enriched uranium as oxide. Revision 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-07-05

This Conversion and Blending Facility (CBF) will have two missions: (1) convert HEU materials into pure HEU oxide and (2) blend the pure HEU oxide with depleted and natural uranium oxide to produce an LWR grade LEU product. The primary emphasis of this blending operation will be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. To the extent practical, the chemical and isotopic concentrations of blended LEU product will be held within the specifications required for LWR fuel. Such blended LEU product will be offered to the United States Enrichment Corporation (USEC) to be sold as feed material to the commercial nuclear industry. Otherwise, blended LEU will be produced as a waste suitable for storage or disposal.

Production of Mo-99 using low-enriched uranium silicide

International Nuclear Information System (INIS)

Hutter, J.C.; Srinivasan, B.; Vicek, M.; Vandegrift, G.F.

1994-01-01

Over the last several years, uranium silicide fuels have been under development as low-enriched uranium (LEU) targets for Mo-99. The use of LEU silicide is aimed at replacing the UAl x alloy in the highly-enriched uranium dissolution process. A process to recover Mo-99 from low-enriched uranium silicide is being developed at Argonne National Laboratory. The uranium silicide is dissolved in alkaline hydrogen peroxide. Experiments performed to determine the optimum dissolution procedure are discussed, and the results of dissolving a portion of a high-burnup (>40%) U 3 Si 2 miniplate are presented. Future work related to Mo-99 separation and waste disposal are also discussed

Enrichment 2.0 Gifted and Talented Education for the 21st Century

Science.gov (United States)

Eckstein, Michelle

2009-01-01

Enrichment clusters, a component of the Schoolwide Enrichment Model, are multigrade investigative groups based on constructivist learning methodology. Enrichment clusters are organized around major disciplines, interdisciplinary themes, or cross-disciplinary topics. Within clusters, students are grouped across grade levels by interests and focused…

Enriched uranium recovery at Los Alamos

International Nuclear Information System (INIS)

Herrick, C.C.

1984-01-01

Graphite casting scrap, fuel elements and nongraphite combustibles are calcined to impure oxides. These materials along with zircaloy fuel elements and refractory solids are leach-dissolved separately in HF-HNO 3 acid to solubilize the contained enriched uranium. The resulting slurry is filtered and the clear filtrate (to which mineral acid solutions bearing enriched uranium may be added) are passed through solvent extraction. The solvent extraction product is filtered, precipitated with H 2 O 2 and the precipitate calcined to U 3 O 8 . Metal is made from U 3 O 8 by conversion to UO 2 , hydrofluorination and reduction to metal. Throughput is 150 to 900 kg uranium per year depending on the type of scrap

Diagenetic silica enrichment and late-stage groundwater activity in Gale crater, Mars

Science.gov (United States)

Frydenvang, Jens; Gasda, Patrick J.; Hurowitz, Joel A.; Grotzinger, John P.; Wiens, Roger C.; Newsom, Horton E.; Edgett, Ken S.; Watkins, Jessica; Bridges, John C.; Maurice, Sylvestre; Fisk, Martin R.; Johnson, Jeffrey R.; Rapin, William; Stein, Nathan; Clegg, Sam M.; Schwenzer, S. P.; Bedford, C.; Edwards, P.; Mangold, Nicolas; Cousin, Agnes; Anderson, Ryan; Payre, Valerie; Vaniman, David; Blake, David; Lanza, Nina L.; Gupta, Sanjeev; Van Beek, Jason; Sautter, Violaine; Meslin, Pierre-Yves; Rice, Melissa; Milliken, Ralf; Gellert, Ralf; Thompson, Lucy; Clark, Ben C.; Sumner, Dawn Y.; Fraeman, Abigail A.; Kinch, Kjartan M; Madsen, Morten B.; Mitofranov, Igor; Jun, Insoo; Calef, Fred J.; Vasavada, Ashwin R.

2017-01-01

Diagenetic silica enrichment in fracture-associated halos that crosscut lacustrine and unconformably overlying aeolian sedimentary bedrock is observed on the lower north slope of Aeolis Mons in Gale crater, Mars. The diagenetic silica enrichment is colocated with detrital silica enrichment observed in the lacustrine bedrock yet extends into a considerably younger, unconformably draping aeolian sandstone, implying that diagenetic silica enrichment postdates the detrital silica enrichment. A causal connection between the detrital and diagenetic silica enrichment implies that water was present in the subsurface of Gale crater long after deposition of the lacustrine sediments and that it mobilized detrital amorphous silica and precipitated it along fractures in the overlying bedrock. Although absolute timing is uncertain, the observed diagenesis likely represents some of the most recent groundwater activity in Gale crater and suggests that the timescale of potential habitability extended considerably beyond the time that the lacustrine sediments of Aeolis Mons were deposited.

Uranium-236 in light water reactor spent fuel recycled to an enriching plant

International Nuclear Information System (INIS)

de la Garza, A.

1977-01-01

The introduction of 236 U to an enriching plant by recycling spent fuel uranium results in enriched products containing 236 U, a parasitic neutron absorber in reactor fuel. Convenient approximate methodology determines 235 236 U, and total uranium flowsheets with associated separative work requirements in enriching plant operations for use by investigators of the light water reactor fuel cycle not having recourse to specialized multicomponent cascade technology. Application of the methodology has been made to compensation of an enriching plant product for 236 U content and to the value at an enriching plant of spent fuel uranium. The approximate methodology was also confirmed with more exact calculations and with some experience with 236 U in an enriching plant

A Resolution of the Paradox of Enrichment

Science.gov (United States)

Feng, Z. C.; Li, Y. Charles

2015-06-01

The paradox of enrichment was observed by Rosenzweig [1971] in a class of predator-prey models. Two of the parameters in the models are crucial for the paradox. These two parameters are the prey's carrying capacity and prey's half-saturation for predation. Intuitively, increasing the carrying capacity due to enrichment of the prey's environment should lead to a more stable predator-prey system. Analytically, it turns out that increasing the carrying capacity always leads to an unstable predator-prey system that is susceptible to extinction from environmental random perturbations. This is the so-called paradox of enrichment. Our resolution here rests upon a closer investigation on a dimensionless number H formed from the carrying capacity and the prey's half-saturation. By recasting the models into dimensionless forms, the models are in fact governed by a few dimensionless numbers including H. The effects of the two parameters: carrying capacity and half-saturation are incorporated into the number H. In fact, increasing the carrying capacity is equivalent (i.e. has the same effect on H) to decreasing the half-saturation which implies more aggressive predation. Since there is no paradox between more aggressive predation and instability of the predator-prey system, the paradox of enrichment is resolved. The so-called instability of the predator-prey system is characterized by the existence of a stable limit cycle in the phase plane, which gets closer and closer to the predator axis and prey axis. Due to random environmental perturbations, this can lead to extinction. We also further explore spatially dependent models for which the phase space is infinite-dimensional. The spatially independent limit cycle which is generated by a Hopf bifurcation from an unstable steady state, is linearly stable in the infinite-dimensional phase space. Numerical simulations indicate that the basin of attraction of the limit cycle is riddled. This shows that spatial perturbations can

Identification of candidate biomarker mass (m/z) ranges in serous ovarian adenocarcinoma using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry profiling.

Science.gov (United States)

Periyasamy, Amutha; Gopisetty, Gopal; Veluswami, Sridevi; Joyimallaya Subramanium, Malliga; Thangarajan, Rajkumar

2015-01-01

To differentiate plasma from ovarian cancer and healthy individuals using MALDI-TOF mass spectroscopy. MALDI-TOF was used to generate profiles of immuno-depleted plasma samples (89 cancers and 199 healthy individuals) that were fractionated using three types of magnetic beads (HIC8, WCX and IMAC-Cu). Differentially expressed mass ranges showing >1.5-2-fold change in expression from HIC8 (30), WCX (12) and IMAC-Cu (6) fractions were identified. Cross validation and recognition capability scores for the models indicated discrimination between the classes. Spectral profiles can differentiate plasma samples of ovarian cancer patients from healthy individuals.

Electrically Cooled Germanium System for Measurements of Uranium Enrichments in UF6 Cylinders

International Nuclear Information System (INIS)

Dvornyak, P.; Koestlbauer, M.; Lebrun, A.; Murray, M.; Nizhnik, V.; Saidler, C.; Twomey, T.

2010-01-01

Measurements of Uranium enrichment in UF6 cylinders is a significant part of the IAEA Safeguards verification activities at enrichment and conversion plants. Nowadays, one of the main tools for verification of Uranium enrichment in UF6 cylinders used by Safeguards inspectors is the gamma spectroscopy system with HPGe detector cooled with liquid nitrogen. Electrically Cooled Germanium System (ECGS) is a new compact and portable high resolution gamma spectrometric system free from liquid nitrogen cooling, which can be used for the same safeguards applications. It consists of the ORTEC Micro-trans-SPEC HPGe Portable Spectrometer, a special tungsten collimator and UF6 enrichment measurement software. The enrichment of uranium is determined by of quantifying the area of the 185.7 keV peak provided that the measurement is performed with a detector viewing an infinite thickness of material. Prior starting the verification of uranium enrichment at the facility, the ECGS has to be calibrated with a sample of known uranium enrichment, material matrix, container wall thickness and container material. Evaluation of the ECGS capabilities was performed by carrying out a field test on actual enrichment verification of uranium in UF6 cylinder or other forms of uranium under infinite thickness conditions. The results of these evaluations allow to say that the use of ECGS will enhance practicality of the enrichment measurements and support unannounced inspection activities at enrichment and conversion plants. (author)

Elephant Management in North American Zoos: Environmental Enrichment, Feeding, Exercise, and Training.

Science.gov (United States)

Greco, Brian J; Meehan, Cheryl L; Miller, Lance J; Shepherdson, David J; Morfeld, Kari A; Andrews, Jeff; Baker, Anne M; Carlstead, Kathy; Mench, Joy A

2016-01-01

The management of African (Loxodonta africana) and Asian (Elephas maximus) elephants in zoos involves a range of practices including feeding, exercise, training, and environmental enrichment. These practices are necessary to meet the elephants' nutritional, healthcare, and husbandry needs. However, these practices are not standardized, resulting in likely variation among zoos as well as differences in the way they are applied to individual elephants within a zoo. To characterize elephant management in North America, we collected survey data from zoos accredited by the Association of Zoos and Aquariums, developed 26 variables, generated population level descriptive statistics, and analyzed them to identify differences attributable to sex and species. Sixty-seven zoos submitted surveys describing the management of 224 elephants and the training experiences of 227 elephants. Asian elephants spent more time managed (defined as interacting directly with staff) than Africans (mean time managed: Asians = 56.9%; Africans = 48.6%; pyear of age for both species. Enrichment, feeding, and exercise programs were evaluated using diversity indices, with mean scores across zoos in the midrange for these measures. There were an average of 7.2 feedings every 24-hour period, with only 1.2 occurring during the nighttime. Feeding schedules were predictable at 47.5% of zoos. We also calculated the relative use of rewarding and aversive techniques employed during training interactions. The population median was seven on a scale from one (representing only aversive stimuli) to nine (representing only rewarding stimuli). The results of our study provide essential information for understanding management variation that could be relevant to welfare. Furthermore, the variables we created have been used in subsequent elephant welfare analyses.

Effects of CO2 Enrichment on Growth and Development of Impatiens hawkeri

Science.gov (United States)

Zhang, Fan-Fan; Wang, Yan-Li; Huang, Zhi-Zhe; Zhu, Xiao-Chen; Zhang, Feng-Jiao; Chen, Fa-Di; Fang, Wei-Min; Teng, Nian-Jun

2012-01-01

The effects of CO2 enrichment on growth and development of Impatiens hawkeri, an important greenhouse flower, were investigated for the purpose of providing scientific basis for CO2 enrichment to this species in greenhouse. The plants were grown in CO2-controlled growth chambers with 380 (the control) and 760 (CO2 enrichment) μmol·mol−1, respectively. The changes in morphology, physiology, biochemistry, and leaf ultrastructure of Impatiens were examined. Results showed that CO2 enrichment increased flower number and relative leaf area compared with the control. In addition, CO2 enrichment significantly enhanced photosynthetic rate, contents of soluble sugars and starch, activities of peroxidase (POD), superoxide dismutase (SOD), and ascorbate peroxidase (APX), but reduced chlorophyll content and malondialdehyde (MDA) content. Furthermore, significant changes in chloroplast ultrastructure were observed at CO2 enrichment: an increased number of starch grains with an expanded size, and an increased ratio of stroma thylakoid to grana thylakoid. These results suggest that CO2 enrichment had positive effects on Impatiens, that is, it can improve the visual value, promote growth and development, and enhance antioxidant capacity. PMID:22536147

Selective enrichment of a methanol-utilizing consortium using pulp & paper mill waste streams

Energy Technology Data Exchange (ETDEWEB)

Gregory R. Mockos; William A. Smith; Frank J. Loge; David N. Thompson

2007-04-01

Efficient utilization of carbon inputs is critical to the economic viability of the current forest products sector. Input carbon losses occur in various locations within a pulp mill, including losses as volatile organics and wastewater . Opportunities exist to capture this carbon in the form of value-added products such as biodegradable polymers. Waste activated sludge from a pulp mill wastewater facility was enriched for 80 days for a methanol-utilizing consortium with the goal of using this consortium to produce biopolymers from methanol-rich pulp mill waste streams. Five enrichment conditions were utilized: three high-methanol streams from the kraft mill foul condensate system, one methanol-amended stream from the mill wastewater plant, and one methanol-only enrichment. Enrichment reactors were operated aerobically in sequencing batch mode at neutral pH and 25°C with a hydraulic residence time and a solids retention time of four days. Non-enriched waste activated sludge did not consume methanol or reduce chemical oxygen demand. With enrichment, however, the chemical oxygen demand reduction over 24 hour feed/decant cycles ranged from 79 to 89 %, and methanol concentrations dropped below method detection limits. Neither the non-enriched waste activated sludge nor any of the enrichment cultures accumulated polyhydroxyalkanoates (PHAs) under conditions of nitrogen sufficiency. Similarly, the non-enriched waste activated sludge did not accumulate PHAs under nitrogen limited conditions. By contrast, enriched cultures accumulated PHAs to nearly 14% on a dry weight basis under nitrogen limited conditions. This indicates that selectively-enriched pulp mill waste activated sludge can serve as an inoculum for PHA production from methanol-rich pulp mill effluents.