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1

Enriching the Web Processing Service  

NASA Astrophysics Data System (ADS)

The OGC Web Processing Service (WPS) provides a standard for implementing geospatial processes in service-oriented networks. In its current version 1.0.0 it allocates the operations GetCapabilities, DescribeProcess and Execute, which can be used to offer custom processes based on single or multiple sub-processes. A large range of ready to use fine granular, fundamental geospatial processes have been developed by the GIS-community in the past. However, modern use cases or whole workflow processes demand specifications of lifecycle management and service orchestration. Orchestrating smaller sub-processes is a task towards interoperability; a comprehensive documentation by using appropriate metadata is also required. Though different approaches were tested in the past, developing complex WPS applications still requires programming skills, knowledge about software libraries in use and a lot of effort for integration. Our toolset RichWPS aims at providing a better overall experience by setting up two major components. The RichWPS ModelBuilder enables the graphics-aided design of workflow processes based on existing local and distributed processes and geospatial services. Once tested by the RichWPS Server, a composition can be deployed for production use on the RichWPS Server. The ModelBuilder obtains necessary processes and services from a directory service, the RichWPS semantic proxy. It manages the lifecycle and is able to visualize results and debugging-information. One aim will be to generate reproducible results; the workflow should be documented by metadata that can be integrated in Spatial Data Infrastructures. The RichWPS Server provides a set of interfaces to the ModelBuilder for, among others, testing composed workflow sequences, estimating their performance and to publish them as common processes. Therefore the server is oriented towards the upcoming WPS 2.0 standard and its ability to transactionally deploy and undeploy processes making use of a WPS-T interface. In order to deal with the results of these processing workflows, a server side extension enables the RichWPS Server and its clients to use WPS presentation directives (WPS-PD), a content related enhancement for the standardized WPS schema. We identified essential requirements of the components of our toolset by applying two use cases. The first enables the simplified comparison of modeled and measured data, a common task in hydro-engineering to validate the accuracy of a model. An implementation of the workflow includes reading, harmonizing and comparing two datasets in NetCDF-format. 2D Water level data from the German Bight can be chosen, presented and evaluated in a web client with interactive plots. The second use case is motivated by the Marine Strategy Directive (MSD) of the EU, which demands monitoring, action plans and at least an evaluation of the ecological situation in marine environment. Information technics adapted to those of INSPIRE should be used. One of the parameters monitored and evaluated for MSD is the expansion and quality of seagrass fields. With the view towards other evaluation parameters we decompose the complex process of evaluation of seagrass in reusable process steps and implement those packages as configurable WPS.

Wosniok, Christoph; Bensmann, Felix; Wössner, Roman; Kohlus, Jörn; Roosmann, Rainer; Heidmann, Carsten; Lehfeldt, Rainer

2014-05-01

2

Process for the manufacture of enriched pitches and carbon fibers  

Microsoft Academic Search

This patent describes an improved process for the production of carbon fibers. It comprises: treating a petroleum pitch in a system comprising wiped-film evaporator and a means for recovering enriched pitch to obtain an enriched pitch; delivering the enriched pitch to the inlet of the means for recovering enriched pitch at a pressure equivalent to a vertical distance between the

D. C. Berkebile; D. M. Lee; L. D. Veneziano; J. L. Lauer; R. E. Booth; W. P. Hettinger

1991-01-01

3

Novel Membranes and Processes for Oxygen Enrichment  

SciTech Connect

The overall goal of this project is to develop a membrane process that produces air containing 25-35% oxygen, at a cost of $25-40/ton of equivalent pure oxygen (EPO2). Oxygen-enriched air at such a low cost will allow existing air-fueled furnaces to be converted economically to oxygen-enriched furnaces, which in turn will improve the economic and energy efficiency of combustion processes significantly, and reduce the cost of CO{sub 2} capture and sequestration from flue gases throughout the U.S. manufacturing industries. During the 12-month Concept Definition project: We identified a series of perfluoropolymers (PFPs) with promising oxygen/nitrogen separation properties, which were successfully made into thin film composite membranes. The membranes showed oxygen permeance as high as 1,200 gpu and oxygen/nitrogen selectivity of 3.0, and the permeance and selectivity were stable over the time period tested (60 days). We successfully scaled up the production of high-flux PFP-based membranes, using MTR's commercial coaters. Two bench-scale spiral-wound modules with countercurrent designs were made and parametric tests were performed to understand the effect of feed flow rate and pressure, permeate pressure and sweep flow rate on the membrane module separation properties. At various operating conditions that modeled potential industrial operating conditions, the module separation properties were similar to the pure-gas separation properties in the membrane stamps. We also identified and synthesized new polymers [including polymers of intrinsic microporosity (PIMs) and polyimides] with higher oxygen/nitrogen selectivity (3.5-5.0) than the PFPs, and made these polymers into thin film composite membranes. However, these membranes were susceptible to severe aging; pure-gas permeance decreased nearly six-fold within two weeks, making them impractical for industrial applications of oxygen enrichment. We tested the effect of oxygen-enriched air on NO{sub x} emissions using a Bloom baffle burner at GTI. The results are positive and confirm that oxygen-enriched combustion can be carried out without producing higher levels of NOx than normal air firing, if lancing of combustion air is used and the excess air levels are controlled. A simple economic study shows that the membrane processes can produce O{sub 2} at less than $40/ton EPO{sub 2} and an energy cost of 1.1-1.5 MMBtu/ton EPO{sub 2}, which are very favorable compared with conventional technologies such as cryogenics and vacuum pressure swing adsorption processes. The benefits of integrated membrane processes/combustion process trains have been evaluated, and show good savings in process costs and energy consumption, as well as reduced CO{sub 2} emissions. For example, if air containing 30% oxygen is used in natural gas furnaces, the net natural gas savings are an estimated 18% at a burner temperature of 2,500 F, and 32% at a burner temperature of 3,000 F. With a 20% market penetration of membrane-based oxygen-enriched combustion in all combustion processes by 2020, the energy savings would be 414-736 TBtu/y in the U.S. The comparable net cost savings are estimated at $1.2-2.1 billion per year by 2020, calculated as the value of fuel savings subtracted from the cost of oxygen production. The fuel savings of 18%-32% by the membrane/oxygen-enriched combustion corresponds to an 18%-32% reduction in CO{sub 2} emissions, or 23-40 MM ton/y less CO{sub 2} from natural gas-fired furnaces by 2020. In summary, results from this project (Concept Definition phase) are highly promising and clearly demonstrate that membrane processes can produce oxygen-enriched air in a low cost manner that will lower operating costs and energy consumption in industrial combustion processes. Future work will focus on proof-of-concept bench-scale demonstration in the laboratory.

Lin, Haiqing

2011-11-15

4

Interstellar Processes Leading to Molecular Deuterium Enrichment and Their Detection  

NASA Technical Reports Server (NTRS)

Large deuterium (D) enrichments in meteoritic materials indicate that interstellar organic materials survived incorporation into parent bodies within the forming Solar System. These enrichments are likelier due to one or more of four distinct astrochemical processes. These are (1) low temperature gas phase ion-molecule reactions; (2) low temperature gas-grain reactions; (3) gas phase unimolecular photodissociation, and (4) ultraviolet photolysis in D-enriched ice mantles. Each of these processes should be associated with molecular carriers having, distinct regiochemical signatures (D placement on the product molecules, correlation with specific chemical functionalities, etc.). These processes are reviewed and specific spectroscopic signatures for the detection of these processes in space are identified and described.

Sandford, Scott A.; Kliss, Mark (Technical Monitor)

2001-01-01

5

Process of .sup.196 Hg enrichment  

DOEpatents

A simple rate equation model shows that by increasing the length of the photochemical reactor and/or by increasing the photon intensity in said reactor, the feedstock utilization of .sup.196 Hg will be increased. Two preferred embodiments of the present invention are described, namely (1) long reactors using long photochemical lamps and vapor filters; and (2) quartz reactors with external UV reflecting films. These embodiments have each been constructed and operated, demonstrating the enhanced utilization process dictated by the mathematical model (also provided).

Grossman, Mark W. (Belmont, MA); Mellor, Charles E. (Salem, MA)

1993-01-01

6

Process of [sup 196]Hg enrichment  

DOEpatents

A simple rate equation model shows that by increasing the length of the photochemical reactor and/or by increasing the photon intensity in said reactor, the feedstock utilization of [sup 196]Hg will be increased. Two preferred embodiments of the present invention are described, namely (1) long reactors using long photochemical lamps and vapor filters; and (2) quartz reactors with external UV reflecting films. These embodiments have each been constructed and operated, demonstrating the enhanced utilization process dictated by the mathematical model (also provided).

Grossman, M.W.; Mellor, C.E.

1993-04-27

7

Combined system of monothermal chemical exchange process with electrolysis and thermal diffusion process for enriching tritium  

SciTech Connect

Monothermal chemical exchange process with electrolysis (wellknown as the CECE process) is an effective method for enriching and removing tritium from tritiated water of low to middle level activity. The thermal diffusion process (ThD) is a low inventory gas phase method for enriching tritium from hydrogen. ThD and CECE process can be combined with each other by hydrogen gas line.

Kitamoto, A.; Hasegawa, K.; Masui, T.

1988-09-01

8

Process for preparing a chemical compound enriched in isotope content. [nitrogen 15-enriched nitric acid  

DOEpatents

A process to prepare a chemical enriched in isotope content includes: a chemical exchange reaction between a first and second compound which yields an isotopically enriched first compound and an isotopically depleted second compound; the removal of a portion of the first compound as product and the removal of a portion of the second compound as spent material; the conversion of the remainder of the first compound to the second compound for reflux at the product end of the chemical exchange reaction region; the conversion of the remainder of the second compound to the first compound for reflux at the spent material end of the chemical exchange region; and the cycling of the additional chemicals produced by one conversion reaction to the other conversion reaction, for consumption therein. One of the conversion reactions is an oxidation reaction, and the energy that it yields is used to drive the other conversion reaction, a reduction. The reduction reaction is carried out in a solid polymer electrolyte electrolytic reactor. The overall process is energy efficient and yields no waste by-products. A particular embodiment of the process in the production of nitrogen-15-enriched nitric acid.

Michaels, E.D.

1981-02-25

9

Process for preparing a chemical compound enriched in isotope content  

DOEpatents

A process to prepare a chemical enriched in isotope content which includes: (a) A chemical exchange reaction between a first and second compound which yields an isotopically enriched first compound and an isotopically depleted second compound; (b) the removal of a portion of the first compound as product and the removal of a portion of the second compound as spent material; (c) the conversion of the remainder of the first compound to the second compound for reflux at the product end of the chemical exchange reaction region; (d) the conversion of the remainder of the second compound to the first compound for reflux at the spent material end of the chemical exchange region; and the cycling of the additional chemicals produced by one conversion reaction to the other conversion reaction, for consumption therein. One of the conversion reactions is an oxidation reaction, and the energy that it yields is used to drive the other conversion reaction, a reduction. The reduction reaction is carried out in a solid polymer electrolyte electrolytic reactor. The overall process is energy efficient and yields no waste by-products.

Michaels, Edward D. (Spring Valley, OH)

1982-01-01

10

Enrichment and Fundamental Optical Processes of Armchair Carbon Nanotubes  

NASA Astrophysics Data System (ADS)

The armchair variety of single-wall carbon nanotubes (SWCNTs) is the only nanotube species that behaves as a metal with no electronic band gap and massless carriers, making them ideally suited to probe fundamental questions of many-body physics of one-dimensional conductors as well as to serve in applications such as highcurrent power transmission cables. However, current methods of nanotube synthesis produce bulk material comprising of a mixture of nanotube lengths, diameters, wrapping angles, and electronic types due to the inability to control the growth process at the nanometer level. As a result, measurements of as-grown SWCNTs produce a superposition of electrical and optical responses from multiple SWCNT species. This thesis demonstrates production of aqueous suspensions composed almost entirely of armchair SWCNTs using a post-synthesis separation method employing density gradient ultracentrifugation (DGU) to separate different SWCNT types based on their mass density and surfactant-specific interactions. Resonant Raman spectroscopy determines the relative abundances of each nanotube species, before and after DGU, by measuring the integrated intensity of the radial breathing mode, the diameter-dependent radial vibration of the SWCNT perpendicular to its main axis, and quantifies the degree of enrichment of bulk nanotube samples to exclusively armchair tubes. Raman spectroscopy of armchair-enriched samples of the G-band mode, which is composed of longitudinal (G-) and circumferential (G+) vibrations oscillating parallel and perpendicular to the tube axis, shows that the G- peak, long-held to be an indicator for the presence of metallic SWCNTs, appears only when electronic resonance with narrow-gap semiconducting SWCNTs occurs and shows only the G+ component in spectra containing only armchair species. Finally, by combining optical absorption measurements with nanotube composition as determined earlier via Raman scattering, peak fitting of absorption spectra indicates that interband transitions of armchair SWCNTs are strongly excitonic as shown by the highly symmetric peak lineshapes, a property normally attributed to semiconductors. Such lineshapes allow classification of armchair SWCNTs as a unique hybrid class of optical nanomaterial. Combining absorption and Raman scattering measurements establishes a distinct optical signature that describes the fundamental optical processes within armchair SWCNTs and lays the foundation for future studies of many-body photophysics and electrical applications.

Haroz, Erik H.

11

Autoxidation of oil emulsions during the Artemia enrichment process  

Microsoft Academic Search

Autoxidation in three Artemia enrichment emulsions (cod liver oil, tuna orbital oil, and Super Selco (Artemia Systems N.V., Belgium)) were monitored over a 23-h period. Percentage concentrations of docosahexaenoic acid (DHA, 22:6n ? 3), eicosapentaenoic acid (EPA, 20:5n-3), total polyun-saturated, monounsaturated and saturated fatty acids, as well as DHA:EPA ratios were measured in (a) the enriched Artemia nauplii (b) control

L. A. McEvoy; J. C. Navarro; J. G. Bell; J. R. Sargent

1995-01-01

12

Neptunium and plutonium valence adjustment in enriched uranium processing  

Microsoft Academic Search

In initial operation of a new flowsheet for recovery of highly irradiated enriched uranium by solvent extraction with 7.5 vol percent tri-n-butyl phosphate, valence adjustment of plutonium and neptunium with ferrous sulfamate was ineffective; plutonium was not rejected as desired, and neptunium was partially lost to waste. Laboratory studies demonstrated that ferrous sulfamate, added to both the aqueous feed solution

M. C. Thompson; G. A. Burney; M. L. Hyder

1976-01-01

13

Development of dissolution process for metal foil target containing low enriched uranium  

Microsoft Academic Search

About six times more low enriched uranium (LEU) metal is needed to produce the same quantity of ⁹⁹Mo as from a high enriched uranium (HEU) oxide target, under similar conditions of neutron irradiation. In view of this, the post-irradiation processing procedures of the LEU target are likely to be different from the Cintichem process procedures now in use for the

B. Srinivasan; J. C. Hutter; G. K. Johnson; G. F. Vandegrift

1994-01-01

14

Method for thermal processing alumina-enriched spinel single crystals  

DOEpatents

A process for age-hardening alumina-rich magnesium aluminum spinel to obtain the desired combination of characteristics of hardness, clarity, flexural strength and toughness comprises selection of the time-temperature pair for isothermal heating followed by quenching. The time-temperature pair is selected from the region wherein the precipitate groups have the characteristics sought. The single crystal spinel is isothermally heated and will, if heated long enough pass from its single phase through two pre-precipitates and two metastable precipitates to a stable secondary phase precipitate within the spinel matrix. Quenching is done slowly at first to avoid thermal shock, then rapidly.

Jantzen, Carol M. (Aiken, SC)

1995-01-01

15

Method for thermal processing alumina-enriched spinel single crystals  

DOEpatents

A process for age-hardening alumina-rich magnesium aluminum spinel to obtain the desired combination of characteristics of hardness, clarity, flexural strength and toughness comprises selection of the time-temperature pair for isothermal heating followed by quenching. The time-temperature pair is selected from the region wherein the precipitate groups have the characteristics sought. The single crystal spinel is isothermally heated and will, if heated long enough pass from its single phase through two pre-precipitates and two metastable precipitates to a stable secondary phase precipitate within the spinel matrix. Quenching is done slowly at first to avoid thermal shock, then rapidly. 12 figs.

Jantzen, C.M.

1995-05-09

16

Assessment of the Interstellar Processes Leading to Deuterium Enrichment in Meteoritic Organics  

NASA Technical Reports Server (NTRS)

The presence of isotopic anomalies is the most unequivocal demonstration that meteoritic material contains circumstellar or interstellar components. In the case of organic compounds in meteorites and interplanetary dust particles (IDPs), the most useful isotopic tracer has been deuterium (D). We discuss four processes that are expected to lead to D enrichment in interstellar materials and describe how their unique characteristics can be used to assess their relative importance for the organics in meteorites. These enrichment processes are low temperature gas phase ion-molecule reactions, low temperature gas-grain reactions, gas phase unimolecular photodissociation, and ultraviolet photolysis in D-enriched ice mantles. Each of these processes is expected to be associated with distinct regiochemical signatures (D placement on the product molecules, correlation with specific chemical functionalities, etc.), especially in the molecular population of polycyclic aromatic hydrocarbons (PAHs). We describe these differences and discuss how they may be used to delineate the various interstellar processes that may have contributed to meteoritic D enrichments. We also briefly discuss how these processes may affect the isotopic distributions in C, 0, and N in the same compounds.

Sandford, Scott A.; Bernstein, Max P.; Dworkin, Jason P.; DeVincenzi, Donald L. (Technical Monitor)

2001-01-01

17

Syndecan-3 and syndecan-4 are enriched in Schwann cell perinodal processes  

Microsoft Academic Search

BACKGROUND: Nodes of Ranvier correspond to specialized axonal domains where voltage-gated sodium channels are highly concentrated. In the peripheral nervous system, they are covered by Schwann cells microvilli, where three homologous cytoskeletal-associated proteins, ezrin, radixin and moesin (ERM proteins) have been found, to be enriched. These glial processes are thought to play a crucial role in organizing axonal nodal domains

Laurence Goutebroze; Michèle Carnaud; Natalia Denisenko; Marie-Claude Boutterin; Jean-Antoine Girault

2003-01-01

18

Standard signal processing using enriched sensor information for WWTP monitoring and control.  

PubMed

Important indicators for monitoring and control of wastewater treatment plants (WWTP) often have to be obtained from the processing of on-line signal trajectories. Therefore, the quality of sensor instantaneous measurements can be improved significantly if they are complemented with valuable information about the geometric features of their trajectories. The present paper describes the design and implementation of a Standard Signal Processing Architecture (SSPA) from which enriched sensor information is generated automatically. The SSPA has been made up of three complementary modules: the pre-processing module, the storage module and the post-processing module. Moreover, the SSPA has been parameterised so as to allow its adaptation to the specifications of every signal. By performing basic calculations on pre-processed signal trajectories, the storage module produces enriched vectors which collect information of the first and second time derivatives, average and variance values, peak values, linear regression parameters, curvature, etc. Then, the enriched information vectors can be exploited to implement customised monitoring and control tools. In this respect, the effectiveness of the SSPA has been demonstrated in three different practical cases: (1) OUR and KLa identification algorithms; (2) processing of measurements for real-time controllers; and, (3) detection of bend-points in on-line signals of SBR processes. PMID:18441432

Irizar, I; Alferes, J; Larrea, L; Ayesa, E

2008-01-01

19

reMelting curve analysis as a tool for enrichment monitoring in the SELEX process.  

PubMed

Current aptamer selection procedures enable limited control and transparency on how the DNA selection pool is evolving. Affinity tests and binding analyses are not always informative. Here we show that real-time PCR provides a valuable tool for the follow-up of aptamer selection. Limited time, work and amount of amplified ssDNA make this an interesting instrument to set-up a SELEX design and monitor the enrichment of oligonucleotides. reMelting Curve Analysis (rMCA) after reannealing under stringent conditions provides information about enrichment, compared to a random library. Monitoring the SELEX process and optimising conditions by means of the proposed methods can increase the selection efficiency in a controlled way. rMCA is applied in enrichment simulations and three different selection procedures. Our results imply that rMCA can be used for different SELEX designs and different targets. SELEX pool diversity analysis by rMCA has been proven to be a useful, reproducible tool to detect and evaluate enrichment of specific binding aptamers while the selection procedure is being performed. PMID:24325000

Vanbrabant, Jeroen; Leirs, Karen; Vanschoenbeek, Katrijn; Lammertyn, Jeroen; Michiels, Luc

2014-02-01

20

Processes of mantle enrichment and magmatic differentiation in the eastern Snake River Plain: Th isotope evidence  

NASA Astrophysics Data System (ADS)

The ˜ 85 km long Great Rift of southern Idaho bisects the volcanic depression that forms the eastern Snake River Plain. Thorium isotope systematics of compositionally diverse lavas of the Great Rift, including those of Craters of the Moon, record a spectrum of crust and mantle processes. ( 230Th) /( 232Th) ratios range from 0.87 to 1.11 and are enriched in ( 230Th) with respect to ( 238U) by up to 13%. Covariations in Th isotope systematics in lavas from Craters of the Moon reflect crustal assimilation accompanied by fractional crstallization involving accessory phases. Temperatures based on apatite and zircon saturation confirm other estimates of magmatic temperatures and, considered together with volcanic histories, suggest cooling in upper crustal magma chambers at rates of > 10° C/ka. Thermal and chemical evolution of the Great Rift basalts support their differentiation at lower crustal conditions. Although basalts of the eastern Snake River Plain are generally interpreted as having originated in ancient enriched mantle lithosphere beneath southern Idaho, they share remarkable chemical similarities with oceanic basalts derived from enriched sources attributed to mantle plumes. Thorium isotope signatures of the Great Rift basalts are those of depleted mantle, resulting in the most extreme case of disparity between 232Th/238U ratios delimited by Th and Pb isotope systematics. It is difficult to account for this decoupling by invoking subduction-related U enrichment. A more likely explanation is metasomatism of hybrid lithospheric mantle in the wake of the Yellowstone plume.

Reid, Mary R.

1995-04-01

21

Resin-assisted Enrichment of N-terminal Peptides for Characterizing Proteolytic Processing  

SciTech Connect

Proteolytic processing is a ubiquitous, irreversible posttranslational modification that plays an important role in cellular regulation in all living organisms. Herein we report a resin-assisted positive selection method for specifically enriching protein N-terminal peptides to facilitate the characterization of proteolytic processing events by liquid chromatography-tandem mass spectrometry. In this approach, proteins are initially reduced and alkylated and their lysine residues are converted to homoarginines. Then, protein N-termini are selectively converted to reactive thiol groups. We demonstrate that these sequential reactions were achieved with nearly quantitative efficiencies. Thiol-containing N-terminal peptides are then captured (>98% efficiency) by a thiol-affinity resin, a significant improvement over the traditional avidin/biotin enrichment. Application to cell lysates of Aspergillus niger, a filamentous fungus of interest for biomass degradation, enabled the identification of 1672 unique protein N-termini and proteolytic cleavage sites from 690 unique proteins.

Kim, Jong Seo; Dai, Ziyu; Aryal, Uma K.; Moore, Ronald J.; Camp, David G.; Baker, Scott E.; Smith, Richard D.; Qian, Weijun

2013-06-17

22

Enrichment of organochlorine contaminants in the sea surface microlayer: An organic carbon-driven process  

Microsoft Academic Search

Over 50 seawater samples from two different sites—Barcelona (Spain) and Banyuls-sur-Mer (France)—were analyzed in order to study the extent and postulate the processes driving the enrichment of hydrophobic organic pollutants in the sea surface microlayer (SML). A number of individual polychlorinated biphenyl (PCB) congeners (41) were measured to study their partitioning between the particulate (fraction >0.7 ?m) and the dissolved+colloidal

N. García-Flor; C. Guitart; M. Ábalos; J. Dachs; J. M. Bayona; J. Albaigés

2005-01-01

23

Process for producing dry, sulfur-free, CH[sub 4]-enriched synthesis or fuel gas  

Microsoft Academic Search

A process is described for the production of a dry, sulfur-free methane enriched synthesis gas or fuel gas stream comprising: (1) cooling a particulate-free raw synthesis or fuel gas feed stream comprising H[sub 2], CO, CO[sub 2], H[sub 2]O, N[sub 2], H[sub 2]S, COS and with or without methane to a temperature in the range of about 60 F to

E. T. Child; W. L. Jr. Lafferty; R. M. Suggitt; F. C. Jahnke

1993-01-01

24

Process for protein enrichment of cassava by solid substrate fermentation in rural conditions  

SciTech Connect

An artisanal static process for protein enrichment of cassava by solid-state fermentation, developed in laboratory and tested on pilot units in Burundi (Central Africa), provides enriched cassava containing 10.7% of dry matter protein versus 1% before fermentation. Cassava chips, processed into granules of 2-4-mm diameter, are moistened (40% water content) and steamed. After cooling to 40 degrees C, cassava is mixed with a nutritive solution containing the inoculum (Rhizopus oryzae, strain MUCL 28627) and providing the following per 100 g dry matter: 3.4 g urea, 1.5 g KH/sub 2/PO/sub 4/, O.8 g MgSO/sub 4/.7H/sub 2/O, and 22.7 g citric acid. For the fermentation, cassava, with circa 60% moisture content, is spread in a thin layer (2-3 cm thick) on perforated trays and slid into an aerated humidified enclosure. The incubation lasts more or less 65 hours. The production of protein enriched cassava is 3.26 kg dry matter/square m tray. The effects of the variation of the nutritive solution composition and the inoculum conservation period on the protein production are equally discussed. (Refs. 37).

Daubresse, P.; Ntibashirwa, S.; Gheysen, A.; Meyer, J.A.

1987-06-01

25

Using Process Load Cell Information for IAEA Safeguards at Enrichment Plants  

SciTech Connect

Uranium enrichment service providers are expanding existing enrichment plants and constructing new facilities to meet demands resulting from the shutdown of gaseous diffusion plants, the completion of the U.S.-Russia highly enriched uranium downblending program, and the projected global renaissance in nuclear power. The International Atomic Energy Agency (IAEA) conducts verification inspections at safeguarded facilities to provide assurance that signatory States comply with their treaty obligations to use nuclear materials only for peaceful purposes. Continuous, unattended monitoring of load cells in UF{sub 6} feed/withdrawal stations can provide safeguards-relevant process information to make existing safeguards approaches more efficient and effective and enable novel safeguards concepts such as information-driven inspections. The IAEA has indicated that process load cell monitoring will play a central role in future safeguards approaches for large-scale gas centrifuge enrichment plants. This presentation will discuss previous work and future plans related to continuous load cell monitoring, including: (1) algorithms for automated analysis of load cell data, including filtering methods to determine significant weights and eliminate irrelevant impulses; (2) development of metrics for declaration verification and off-normal operation detection ('cylinder counting,' near-real-time mass balancing, F/P/T ratios, etc.); (3) requirements to specify what potentially sensitive data is safeguards relevant, at what point the IAEA gains on-site custody of the data, and what portion of that data can be transmitted off-site; (4) authentication, secure on-site storage, and secure transmission of load cell data; (5) data processing and remote monitoring schemes to control access to sensitive and proprietary information; (6) integration of process load cell data in a layered safeguards approach with cross-check verification; (7) process mock-ups constructed to provide simulated load cell data; (8) hardware and software implementation for process load cell data collection; (9) costs associated with unattended monitoring of load cells (for both operator and inspector) weighed against the potential benefits of having access to such data; (10) results from field tests of load cell data collection systems in operating facilities; and (11) use of unattended load cell data to increase efficiency of on-site inspection schedules and activities.

Laughter, Mark D [ORNL; Whitaker, J Michael [ORNL; Howell, John [University of Glasgow

2010-01-01

26

Ferrite process of electroplating sludge and enrichment of copper by hydrothermal reaction  

Microsoft Academic Search

In this paper, ferrite process of electroplating sludge and enrichment of copper by hydrothermal reaction was investigated. By the hydrothermal treatment, Zn, Ni, Cu, Cr-bearing electroplating sludge can be transformed into high value-added Ni–Zn–Cr ferrite by adding iron source (FeCl3·6H2O) and precipitator. The most optimum reaction conditions were explored: 1.57g\\/g dry sludge as the dosage of FeCl3·6H2O, pH 8.5 of

Dan Chen; Yi-Zhong Yu; Hua-Jun Zhu; Zhong-Zhe Liu; Yun-Feng Xu; Qiang Liu; Guang-Ren Qian

2008-01-01

27

A Monte Carlo Analysis of Gas Centrifuge Enrichment Plant Process Load Cell Data  

SciTech Connect

As uranium enrichment plants increase in number, capacity, and types of separative technology deployed (e.g., gas centrifuge, laser, etc.), more automated safeguards measures are needed to enable the IAEA to maintain safeguards effectiveness in a fiscally constrained environment. Monitoring load cell data can significantly increase the IAEA s ability to efficiently achieve the fundamental safeguards objective of confirming operations as declared (i.e., no undeclared activities), but care must be taken to fully protect the operator s proprietary and classified information related to operations. Staff at ORNL, LANL, JRC/ISPRA, and University of Glasgow are investigating monitoring the process load cells at feed and withdrawal (F/W) stations to improve international safeguards at enrichment plants. A key question that must be resolved is what is the necessary frequency of recording data from the process F/W stations? Several studies have analyzed data collected at a fixed frequency. This paper contributes to load cell process monitoring research by presenting an analysis of Monte Carlo simulations to determine the expected errors caused by low frequency sampling and its impact on material balance calculations.

Garner, James R [ORNL; Whitaker, J Michael [ORNL

2013-01-01

28

CONCEPTUAL PROCESS DESCRIPTION FOR THE MANUFACTURE OF LOW-ENRICHED URANIUM-MOLYBDENUM FUEL  

SciTech Connect

The National Nuclear Security Agency Global Threat Reduction Initiative (GTRI) is tasked with minimizing the use of high-enriched uranium (HEU) worldwide. A key component of that effort is the conversion of research reactors from HEU to low-enriched uranium (LEU) fuels. The GTRI Convert Fuel Development program, previously known as the Reduced Enrichment for Research and Test Reactors program was initiated in 1978 by the United States Department of Energy to develop the nuclear fuels necessary to enable these conversions. The program cooperates with the research reactors’ operators to achieve this goal of HEU to LEU conversion without reduction in reactor performance. The programmatic mandate is to complete the conversion of all civilian domestic research reactors by 2014. These reactors include the five domestic high-performance research reactors (HPRR), namely: the High Flux Isotope Reactor at the Oak Ridge National Laboratory, the Advanced Test Reactor at the Idaho National Laboratory, the National Bureau of Standards Reactor at the National Institute of Standards and Technology, the Missouri University Research Reactor at the University of Missouri–Columbia, and the MIT Reactor-II at the Massachusetts Institute of Technology. Characteristics for each of the HPRRs are given in Appendix A. The GTRI Convert Fuel Development program is currently engaged in the development of a novel nuclear fuel that will enable these conversions. The fuel design is based on a monolithic fuel meat (made from a uranium-molybdenum alloy) clad in Al-6061 that has shown excellent performance in irradiation testing. The unique aspects of the fuel design, however, necessitate the development and implementation of new fabrication techniques and, thus, establishment of the infrastructure to ensure adequate fuel fabrication capability. A conceptual fabrication process description and rough estimates of the total facility throughput are described in this document as a basis for establishing preconceptual fabrication facility designs.

Daniel M. Wachs; Curtis R. Clark; Randall J. Dunavant

2008-02-01

29

Gene-ontology enrichment analysis in two independent family-based samples highlights biologically plausible processes for autism spectrum disorders  

PubMed Central

Recent genome-wide association studies (GWAS) have implicated a range of genes from discrete biological pathways in the aetiology of autism. However, despite the strong influence of genetic factors, association studies have yet to identify statistically robust, replicated major effect genes or SNPs. We apply the principle of the SNP ratio test methodology described by O'Dushlaine et al to over 2100 families from the Autism Genome Project (AGP). Using a two-stage design we examine association enrichment in 5955 unique gene-ontology classifications across four groupings based on two phenotypic and two ancestral classifications. Based on estimates from simulation we identify excess of association enrichment across all analyses. We observe enrichment in association for sets of genes involved in diverse biological processes, including pyruvate metabolism, transcription factor activation, cell-signalling and cell-cycle regulation. Both genes and processes that show enrichment have previously been examined in autistic disorders and offer biologically plausibility to these findings.

Anney, Richard J L; Kenny, Elaine M; O'Dushlaine, Colm; Yaspan, Brian L; Parkhomenka, Elena; Buxbaum, Joseph D; Sutcliffe, James; Gill, Michael; Gallagher, Louise; Bailey§, Anthony J; Fernandez, Bridget A; Szatmari§, Peter; Scherer§, Stephen W; Patterson§, Andrew; Marshall, Christian R; Pinto, Dalila; Vincent, John B; Fombonne, Eric; Betancur§, Catalina; Delorme, Richard; Leboyer, Marion; Bourgeron, Thomas; Mantoulan, Carine; Roge, Bernadette; Tauber, Maïté; Freitag§, Christine M; Poustka, Fritz; Duketis, Eftichia; Klauck§, Sabine M; Poustka, Annemarie; Papanikolaou, Katerina; Tsiantis, John; Gallagher§, Louise; Gill§, Michael; Anney, Richard; Bolshakova, Nadia; Brennan, Sean; Hughes, Gillian; McGrath, Jane; Merikangas, Alison; Ennis§, Sean; Green, Andrew; Casey, Jillian P; Conroy, Judith M; Regan, Regina; Shah, Naisha; Maestrini§, Elena; Bacchelli, Elena; Minopoli, Fiorella; Stoppioni, Vera; Battaglia§, Agatino; Igliozzi, Roberta; Parrini, Barbara; Tancredi, Raffaella; Oliveira§, Guiomar; Almeida, Joana; Duque, Frederico; Vicente§, Astrid; Correia, Catarina; Magalhaes, Tiago R; Gillberg, Christopher; Nygren, Gudrun; Jonge, Maretha de; Van Engeland, Herman; Vorstman, Jacob AS; Wittemeyer, Kerstin; Baird, Gillian; Bolton, Patrick F; Rutter, Michael L; Green, Jonathan; Lamb, Janine A; Pickles, Andrew; Parr, Jeremy R; Couteur, Ann Le; Berney, Tom; McConachie, Helen; Wallace, Simon; Coutanche, Marc; Foley, Suzanne; White, Kathy; Monaco§, Anthony P; Holt, Richard; Farrar, Penny; Pagnamenta, Alistair T; Mirza, Ghazala K; Ragoussis, Jiannis; Sousa, Inês; Sykes, Nuala; Wing, Kirsty; Hallmayer§, Joachim; Cantor§, Rita M; Nelson, Stanley F; Geschwind§, Daniel H; Abrahams, Brett S; Volkmar, Fred; Pericak-Vance§, Margaret A; Cuccaro, Michael L; Gilbert, John; Cook§, Edwin H; Guter, Stephen J; Jacob, Suma; Nurnberger Jr§, John I; McDougle, Christopher J; Posey, David J; Lord, Catherine; Corsello, Christina; Hus, Vanessa; Buxbaum§, Joseph D; Kolevzon, Alexander; Soorya, Latha; Parkhomenko, Elena; Leventhal, Bennett L; Dawson, Geraldine; Vieland§, Veronica J; Hakonarson§, Hakon; Glessner, Joseph T; Kim, Cecilia; Wang, Kai; Schellenberg§, Gerard D; Devlin§, Bernie; Klei, Lamburtus; Minshew, Nancy; Sutcliffe§, James S; Haines§, Jonathan L; Lund, Sabata C; Thomson, Susanne; Yaspan, Brian L; Coon§, Hilary; Miller, Judith; McMahon, William M; Munson, Jeff; Estes, Annette; Wijsman§, Ellen M; Buxbaum, Joseph D; Sutcliffe, James; Gill, Michael; Gallagher, Louise

2011-01-01

30

Biomass of Spirulina maxima enriched by biosorption process as a new feed supplement for swine.  

PubMed

This paper deals with the new mineral feed additives with Cu produced in a biosorption process from a semi-technical scale. The natural biomass of edible microalga Spirulina sp. was enriched with Cu(II) and then used as a mineral supplement in feeding experiments on swine to assess its nutrition properties. A total of 24 piglets divided into two groups (control and experimental) were used to determine the bioavailability of a new generation of mineral feed additives based on Spirulina maxima. The control group was feed using traditional inorganic supplements of microelements, while the experimental group was fed with the feed containing the biomass of S. maxima enriched with Cu by biosorption. The apparent absorption was 30 % (P?

Saeid, A; Chojnacka, K; Korczy?ski, M; Korniewicz, D; Dobrza?ski, Z

2013-04-01

31

A Search for Gas-Phase Zirconium in s-process Enriched Planetary Nebulae  

NASA Astrophysics Data System (ADS)

We report results from a search for the ground-state fine-structure line of triply ionized zirconium (Zr) near 8 microns, for several planetary nebulae known to have enhanced abundances of other light neutron-capture elements. The observations were made with the high spectral resolution mid-IR spectrometer TEXES (Lacy et al. 2002, PASP, 114, 153) on the IRTF. Zr, atomic number Z = 40, is part of the “light s-process” peak of nuclei which are synthesized in the region between the H and He-burning shells within AGB stars and mixed into the stellar envelope by dredge-up processes before expulsion of a planetary nebula. The targets included objects for which we have demonstrated that Ge (Z = 32) is enhanced by up to a factor of 5 (Sterling et al. 2005, ApJ, 625, 368), and Kr (Z = 36) is enhanced by factors of up to 10 (Sterling et al. 2006, submitted; Sterling & Dinerstein, in preparation). According to both evolutionary models and observations of Galactic S-type stars, Zr can be even more highly enriched than Ge or Kr, with enrichment factors of up to 20 30 (Busso et al. 2001, ApJ, 557, 802; Vanture & Wallerstein 2002, ApJ, 564, 397). If Zr is present primarily in gaseous form in these planetary nebulae, our failure to detect the mid-IR Zr line sets constraints on a combination of the initial mass of the progenitor stars and the details of the s-process and convective mixing. An alternate interpretation is that much of the Zr, a highly refractory element, is locked up in dust grains that formed in the AGB star’s atmosphere before or during envelope ejection. This research was supported by NSF grants AST 97-31156 and 04-06809.

Dinerstein, Harriet L.; Lacy, J. H.; Sellgren, K.; Sterling, N. C.

2006-12-01

32

Theorie et pratique de la traduction professionelle: differences de point de vue et enrichissement mutuel (Professional Translation Theory and Practice: Different Perspectives and Mutual Enrichment).  

ERIC Educational Resources Information Center

Argues against the proliferation of translation theories and theoretical courses for translators, stating a preference for an approach that focuses on practical principles. Also discusses issues such as the relationship between lexicology and terminology, the editor's role, and translator's qualifications and responsibilities towards the receptor.…

Darbelnet, Jean

1980-01-01

33

The evolution from Miocene potassic to Quaternary sodic magmatism in western Turkey: implications for enrichment processes in the lithospheric mantle  

NASA Astrophysics Data System (ADS)

New K-Ar dating and major- and trace-element analyses from the U?ak-Selendi-Emet (USE) area constrain the timing of changes in the nature of volcanism in the Miocene in western Turkey. The data reveal a change from dominantly calc-alkaline and silicic in the Early Miocene to largely alkaline and more mafic volcanism in the Middle Miocene. This probably reflects a decreasing amount of crustal contamination with time, a result of extensional tectonics. High levels of various incompatible elements (including K) in the more mafic members, suggest an enriched subcontinental lithospheric source region for the Middle Miocene USE lavas. Highly variable {Nb}/{Y}, {Ti}/{Y} and {Th}/{Nb} ratios suggest a lithospheric mantle heterogeneously enriched by two processes: (1) enrichment by subduction-related processes producing high {Th}/{Nb} but low {Nb}/{Y} and {Ti}/{Y}; and (2) enrichment by small degree melts of depleted upper mantle producing low {Th}/{Nb} but high {Nb}/{Y} and {Ti}/{Y}. Both of these enrichment processes have variably contributed to Middle Miocene K-rich lavas in the USE area. The mechanism which initiated the melting of the enriched lithosphere is considered to be extension which produced decompression melting. Comparisons with the nearby Kula lavas reveals that by the Pliocene to Quaternary, volcanism, although still enriched in incompatible elements, had become sodic. It seems likely that continued extension up to this time thinned the lithosphere to such an extent that asthenospheric melts were produced which ascended and mixed with previously enriched lithosphere.

Seyito?lu, Gürol; Anderson, Duncan; Nowell, Geoff; Scott, Barry

1997-03-01

34

Tritium-enrichment via CECE-process with high temperature steam electrolysis (HOT ELLY)  

SciTech Connect

Aqueous waste which is a by-product of nuclear fuel reprocessing plants, is contaminated with tritium in the form of HTO. This waste must be disposed of in a suitable compact manner. In order to minimize waste volume, tritiated water is enriched by several orders of magnitude of its original concentration. This task is accomplished by using the existing combined electrolysis catalytic exchange (CECE)-Process, which is presently in pilot operation with tritium in a German nuclear research facility (Kernforschungszentrum Karlsruhe, KfK, FRG). Substantial energy reduction can be achieved by substituting the conventional water electrolysis by high-temperature steam electrolysis (HOT ELLY) for separating tritiated water into its components.

Keil, W.; Erdle, E.

1988-09-01

35

Tritium-Enrichment Via CECE-Process (Combined Electrolysis Catalytic Exchange - Process) with High-Temperature Steam Electrolysis (HOT ELLY). Final Report.  

National Technical Information Service (NTIS)

Reprocessing of nuclear fuel elements produces tritiated water which has to be disposed of for final storage. The amount of waste can be significantly reduced by tritium-enrichment. Besides distillation the CECE-process (Combined Electrolysis Catalytic Ex...

E. Erdle W. Keil

1988-01-01

36

Development of enriched 106CdWO 4 crystal scintillators to search for double ? decay processes in 106Cd  

NASA Astrophysics Data System (ADS)

A cadmium tungstate crystal scintillator enriched in 106Cd was developed for an experiment to search for double beta processes in 106Cd. With this aim samples of cadmium with natural isotopic composition and enriched in 106Cd were purified by vacuum distillation. Cadmium tungstate compounds were synthesized from solutions. The absolute isotopic composition of the enriched cadmium was accurately determined as 66.4% by thermal ionisation mass-spectrometry. A 106CdWO 4 crystal boule was grown by the low-thermal-gradient Czochralski technique. The total irrecoverable loss of the enriched cadmium in all the stages of the crystal scintillator production does not exceed 2.3%. The produced 106CdWO 4 crystal scintillator with mass of 216 g exhibits good optical and scintillation properties.

Belli, P.; Bernabei, R.; Boiko, R. S.; Brudanin, V. B.; Bukilic, N.; Cerulli, R.; Chernyak, D. M.; Danevich, F. A.; d'Angelo, S.; Degoda, V. Ya.; Dossovitskiy, A. E.; Galashov, E. N.; Hyzhnyi, Yu. A.; Ildyakov, S. V.; Incicchitti, A.; Kobychev, V. V.; Kolesnyk, O. S.; Kovtun, G. P.; Kudovbenko, V. M.; de Laeter, J. R.; Mikhlin, A. L.; Nagorny, S. S.; Nedilko, S. G.; Nikolaiko, A. S.; Nisi, S.; Poda, D. V.; Podviyanuk, R. B.; Polischuk, O. G.; Prosperi, D.; Shcherban, A. P.; Shcherbatskyi, V. P.; Shlegel, V. N.; Solopikhin, D. A.; Stenin, Yu. G.; Tretyak, V. I.; Vasiliev, Ya. V.; Virich, V. D.

2010-04-01

37

Development of dissolution process for metal foil target containing low enriched uranium.  

National Technical Information Service (NTIS)

About six times more low enriched uranium (LEU) metal is needed to produce the same quantity of (sup 99)Mo as from a high enriched uranium (HEU) oxide target, under similar conditions of neutron irradiation. In view of this, the post-irradiation processin...

B. Srinivasan J. C. Hutter G. K. Johnson G. F. Vandegrift

1994-01-01

38

Free-air carbon dioxide enrichment: A new approach to research on carbon exchange processes  

SciTech Connect

Terrestrial-atmospheric carbon balances are currently poorly understood and are vital for predicting future trends in the global carbon budget. Uncertainties in C exchange rates can best be reduced by realistic experiments to determine flux rates in managed and natural ecosystems. Such experiments must minimize any artificiality imposed by the apparatus and should be capable of economical and reliable operation over entire growing seasons or longer. Brookhaven National Laboratory (BNL) has developed a system for exposing field-grown plants to controlled elevated concentrations of atmospheric gases, including CO{sub 2}, without use of confining chambers that alter important atmospheric exchange processes. This system, called FACE for Free Air CO{sub 2} Enrichment, has been proven in over 15000 hours of testing at three locations. FACE uses a 15--27 m. diameter array of vertical ventpipes and offers significant improvements over previous attempts at chamber-free fumigation. BNL's FACE arrays have demonstrated these capabilities in experiment on field-grown cotton. This paper reviews the design concepts of FACE and presents operational results from several recent field campaigns involving seasonal fumigation of field-grown cotton with CO{sub 2} at concentrations ranging from 500--700 ppm. The use of chamber-free experiments in conjunction with mathematical models of plant growth is discussed as a paradigm for assessing climate change effects on vegetation. 14 refs., 6 figs., 1 tab.

Hendrey, G.R.; Lipfert, F.W.; Lewin, K.F.; Nagy, J.

1991-04-01

39

Effects of Environmental Enrichment on Rate of Contextual Processing and Discriminative Ability in Adult Rats  

Microsoft Academic Search

The effect of environmental enrichment on conditioned freezing to contextual cues in adult Sprague-Dawley rats was examined. The freezing of both enriched-and standard-reared rats increased with the time spent in the chamber prior to shock. Both groups of rats showed equally low levels of contextual conditioning following a preshock period of 4 s and equally high levels following a 120-s

Elizabeth A. Woodcock; Rick Richardson

2000-01-01

40

Tritium-enrichment via CECE-process with high temperature steam electrolysis (HOT ELLY)  

Microsoft Academic Search

Aqueous waste which is a by-product of nuclear fuel reprocessing plants, is contaminated with tritium in the form of HTO. This waste must be disposed of in a suitable compact manner. In order to minimize waste volume, tritiated water is enriched by several orders of magnitude of its original concentration. This task is accomplished by using the existing combined electrolysis

W. Keil; E. Erdle

1988-01-01

41

The Evolution of a Process: Language Arts Curriculum Enrichment in Rural Alabama High Schools.  

ERIC Educational Resources Information Center

Flexibility and change have characterized the 3-year history of the English curriculum-enrichment component of the Biomedical Sciences Preparatory Program (BioPrep)--a program that stresses science for rural high school students but includes the importance of writing and communication skills. In the program's first year the curriculum team set out…

Zielinski, David R.

42

Alkaline peroxide processing of low-enriched uranium targets for ⁹⁹Mo production -- Decomposition of hydrogen peroxide  

Microsoft Academic Search

The recent progress on the alkaline peroxide processing of low-enriched uranium targets for the production of ⁹⁹Mo, a parent nuclide of the widely used medical isotope {sup 99m}Tc, is reported. Kinetic studies were undertaken to investigate the decomposition of hydrogen peroxide in alkaline solution in contact with a uranium metal surface. It was found that the decomposition of hydrogen peroxide

D. Dong; G. F. Vandegrift

1997-01-01

43

Process for tritium removal from water by transfer of tritium from water to an elemental hydrogen stream, followed by membrane diffusion tritium stripping and enrichment, and final tritium enrichment by thermal diffusion  

US Patent & Trademark Office Database

A diffusion based process for tritium removal from water by tritium transfer from water to an elemental hydrogen stream, followed by a membrane diffusion cascade for tritium stripping and enrichment, and final tritium enrichment by one or more thermal diffusion columns. The combination of process steps takes advantage of membrane diffusion's large throughput capability at low tritium concentration with the simplicity of thermal diffusion for small throughput final tritium enrichment. The membrane diffusion stages use supported or unsupported microporous or hydrogen permeable metal membranes (such as Pd/Ag alloy). The diffusion process is compatible with any front-end process to transfer tritium from tritiated water to elemental hydrogen. The process may be designed and operated at low pressure, with small gas inventory, and no inherent overpressure hazard.

2010-10-19

44

Preparation of a Crosslinked Bioimprinted Lipase for Enrichment of Polyunsaturated Fatty Acids from Fish Processing Waste  

Microsoft Academic Search

Geotrichum sp. lipase modified with a combined method composed of crosslinking and bioimprinting was employed to selectively hydrolyze\\u000a waste fish oil for enrichment of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in glycerides. Crosslinked polymerization\\u000a by monomer (polyethylene glycol 400 dimethyl acrylate), crosslinker (trimethylolpropane trimethylacrylate), and photoinitiator\\u000a (benzoin methyl ether) coupled to bioimprinting using palmitic acid as imprint molecule, resulted

Jinyong Yan; Lifan Li; Qianli Tang; Manzhou Jiang; Shenzhou Jiang

2010-01-01

45

Reduction of combustion by-products in WTE plants: O2 enrichment of underfire air in the MARTIN SYNCOM process.  

PubMed

The SYNCOM process involves oxygen enrichment of underfire air, recirculation of flue gas and a combustion control system using infrared thermography of the waste layer on the grate. At the demonstration plant in Coburg, operational reliability and plant availability using SYNCOM could be proven under real disposal conditions with a waste throughput of 7 t/h. Oxygen enrichment of the underfire air promotes the destruction of pollutants due to the high oxygen partial pressures and temperatures. This is then reflected in very low residual amounts of organic combustion by-products in the bottom ash and flue gas from the SYNCOM unit. The flue gas concentrations of organic pollutants are reduced, as compared with conventional operation, by over 35% (for CO, total hydrocarbons and PCDD/F) at the boiler outlet. As the flue gas flow is reduced by oxygen enrichment and flue gas recirculation, the resulting reduction in terms of kg of pollutant per Mg of waste is even higher. In the bottom ash, the level of organic residues is reduced, by 45% in the case of loss on ignition and by 55% in the case of TOC and dioxins (I-TE of PCDD/F). This is due to the higher oxygen partial pressures and the fuel bed temperature which is increased by 135 to 1200 degrees C. Other important features of the process include more intense sintering and thus improved immobilization of the bottom ash, as well as reduced flue gas and fly ash flows. PMID:11219678

Gohlke, O; Busch, M

2001-01-01

46

Full-scale demonstration of the cintichem process for the production of Mo-99 using a low-enriched target.  

SciTech Connect

The irradiation, disassembly, and processing of two full-scale low-enriched uranium (LEU) targets were recently demonstrated by personnel in the BATAN PUSPIPTEK Facilities (Serpong, Indonesia). Targets were fabricated at Argonne National Laboratory (Argonne, IL, U.S.A.) and shipped to PUSPIPTEK. The processing was done by nearly the same procedure used for the production of {sup 99}Mo from high-enriched uranium (HEU) targets. The BATAN Radioisotope Production Centre produces {sup 99}Mo using the Cintichem process by first dissolving the uranium in an acid cocktail; three proprietary separation steps recover the {sup 99}Mo and purify it from other components of the irradiated uranium. Processing of LEU-metal targets is nearly identical to that used for HEU-oxide targets except (1) a separate dissolver is required and (2) the dissolution cocktail is nitric acid alone rather than a nitric/sulfuric acid mixture. The demonstrations went smoothly except for problems with sampling and gamma analysis to assess product purity. Foils could be removed from targets fabricated from zirconium and/or 304 stainless steel, and processing produced an equivalent yield of {sup 99}Mo/{sup 235}U to that of the HEU target.

Mutalib, A.

1998-10-28

47

Process for producing enriched uranium having a {sup 235}U content of at least 4 wt. % via combination of a gaseous diffusion process and an atomic vapor laser isotope separation process to eliminate uranium hexafluoride tails storage  

DOEpatents

An uranium enrichment process capable of producing an enriched uranium, having a {sup 235}U content greater than about 4 wt. %, is disclosed which will consume less energy and produce metallic uranium tails having a lower {sup 235}U content than the tails normally produced in a gaseous diffusion separation process and, therefore, eliminate UF{sub 6} tails storage and sharply reduce fluorine use. The uranium enrichment process comprises feeding metallic uranium into an atomic vapor laser isotope separation process to produce an enriched metallic uranium isotopic mixture having a {sup 235} U content of at least about 2 wt. % and a metallic uranium residue containing from about 0.1 wt. % to about 0.2 wt. % {sup 235} U; fluorinating this enriched metallic uranium isotopic mixture to form UF{sub 6}; processing the resultant isotopic mixture of UF{sub 6} in a gaseous diffusion process to produce a final enriched uranium product having a {sup 235}U content of at least 4 wt. %, and up to 93.5 wt. % or higher, of the total uranium content of the product, and a low {sup 235}U content UF{sub 6} having a {sup 235}U content of about 0.71 wt. % of the total uranium content of the low {sup 235}U content UF{sub 6}; and converting this low {sup 235}U content UF{sub 6} to metallic uranium for recycle to the atomic vapor laser isotope separation process. 4 figs.

Horton, J.A.; Hayden, H.W. Jr.

1995-05-30

48

Interface processes between iron containing aluminosilicate systems and simulated body fluid enriched with protein  

Microsoft Academic Search

The behaviour of iron containing aluminosilicate samples in Kokubo’s simulated body fluid (SBF) and in SBF enriched with bovine\\u000a serum albumin (BSA) has been investigated. Crystalline samples of (80–x)SiO2·20Al2O3·xFe2O3 system, with x = 5, 10 or 15 mol%, obtained by sol–gel method and heat treated at 1200°C in air for 24 h. Data on electrical\\u000a conductivity, calcium, phosphorous and potassium concentrations in simulated body

K. Magyari; O. Popescu; V. Simon

2010-01-01

49

Interface processes between iron containing aluminosilicate systems and simulated body fluid enriched with protein.  

PubMed

The behaviour of iron containing aluminosilicate samples in Kokubo's simulated body fluid (SBF) and in SBF enriched with bovine serum albumin (BSA) has been investigated. Crystalline samples of (80-x)SiO2 X 20Al2O3 X Fe2O3 system, with x = 5, 10 or 15 mol%, obtained by sol-gel method and heat treated at 1200 degrees C in air for 24 h. Data on electrical conductivity, calcium, phosphorous and potassium concentrations in simulated body fluids after samples soaking in static regime at 37 degrees C, for several periods up to 14 days, were used to estimate the dynamics of these cations on the interface of aluminosilicate samples with SBF, and with SBF containing BSA. The UV-visible and fluorescence spectra recorded from the simulated body fluids after immersion of the investigated aluminosilicate samples evidence changes function on immersion time and Fe2O3 content. PMID:20224936

Magyari, K; Popescu, O; Simon, V

2010-06-01

50

Real-time image processing for label-free enrichment of Actinobacteria cultivated in picolitre droplets.  

PubMed

The majority of today's antimicrobial therapeutics is derived from secondary metabolites produced by Actinobacteria. While it is generally assumed that less than 1% of Actinobacteria species from soil habitats have been cultivated so far, classic screening approaches fail to supply new substances, often due to limited throughput and frequent rediscovery of already known strains. To overcome these restrictions, we implement high-throughput cultivation of soil-derived Actinobacteria in microfluidic pL-droplets by generating more than 600,000 pure cultures per hour from a spore suspension that can subsequently be incubated for days to weeks. Moreover, we introduce triggered imaging with real-time image-based droplet classification as a novel universal method for pL-droplet sorting. Growth-dependent droplet sorting at frequencies above 100 Hz is performed for label-free enrichment and extraction of microcultures. The combination of both cultivation of Actinobacteria in pL-droplets and real-time detection of growing Actinobacteria has great potential in screening for yet unknown species as well as their undiscovered natural products. PMID:23881253

Zang, Emerson; Brandes, Susanne; Tovar, Miguel; Martin, Karin; Mech, Franziska; Horbert, Peter; Henkel, Thomas; Figge, Marc Thilo; Roth, Martin

2013-09-21

51

Selective Enrichment of DJ-1 Protein in Primate Striatal Neuronal Processes: Implications for Parkinson's Disease  

PubMed Central

Mutations in DJ-1 cause autosomal recessive, early-onset Parkinson's disease (PD). The precise function and distribution of DJ-1 in the central nervous system remain unclear. In this study, we performed a comprehensive analysis of DJ-1 expression in human, monkey, and rat brains using antibodies that recognize distinct, evolutionarily conserved epitopes of DJ-1. We found that DJ-1 displays region-specific neuronal and glial labeling in human and non-human primate brain, sharply contrasting the primarily neuronal expression pattern observed throughout rat brain. Further immunohistochemical analysis of DJ-1 expression in human and non-human primate brains showed that DJ-1 protein is expressed in neurons within the substantia nigra pars compacta and striatum, two regions critically involved in PD pathogenesis. Moreover, immunoelectron microscopic analysis revealed a selective enrichment of DJ-1 within primate striatal axons, presynaptic terminals, and dendritic spines with respect to the DJ-1 expression in prefrontal cortex. Together, these findings indicate neuronal and synaptic expression of DJ-1 in primate subcortical brain regions and suggest a physiological role for DJ-1 in the survival and/or function of nigral-striatal neurons.

OLZMANN, JAMES A.; BORDELON, JILL R.; MULY, E. CHRIS; REES, HOWARD D.; LEVEY, ALLAN I.; LI, LIAN; CHIN, LIH-SHEN

2008-01-01

52

The role of Rhes, Ras homolog enriched in striatum, in neurodegenerative processes.  

PubMed

Rhes is a small GTPase whose expression is highly enriched in striatum. It shares homology with Ras proteins, but also contains a C-terminal extension, thus suggesting additional functions. Signaling by 7 transmembrane receptors through heterotrimeric G proteins is inhibited by Rhes. However, perhaps the most remarkable feature of this small GTPase described thus far is that it can account for the selective vulnerability of the striatum in Huntington's Disease (HD). HD is an autosomal dominant neurodegenerative disease caused by a poly-glutamine expansion in the protein huntingtin. Despite the presence of huntingtin throughout the brain and the rest of the body, the striatum is selectively degenerated. Recent work shows that Rhes acts as an E3 ligase for attachment of SUMO (small ubiquitin-like modifier). As this post-translational modification decreases the formation of huntingtin aggregates and promotes cell death, this property of Rhes offers an explanation for selective striatal vulnerability in HD. In addition, the sequestering of Rhes through its binding to mutant huntingtin may decrease the ability of Rhes to perform vital physiological functions in the neuron. Thus, as Rhes is an attractive candidate for HD therapy, a thorough understanding of its physiological functions will allow for specific targeting of its pathological functions. PMID:23583659

Harrison, Laura M; Lahoste, Gerald J

2013-09-10

53

Enrichment history of r-process elements shaped by a merger of neutron star pairs  

NASA Astrophysics Data System (ADS)

The origin of r-process elements remains unidentified and still puzzles us. The recent discovery of evidence for the ejection of r-process elements from a short-duration ?-ray burst singled out neutron star mergers (NSMs) as their origin. In contrast, core-collapse supernovae are ruled out as the main origin of heavy r-process elements (A > 110) by recent numerical simulations. However, the properties characterizing NSM events - their rarity and high yield of r-process elements per event - have been claimed to be incompatible with the observed stellar records on r-process elements in the Galaxy. We add to this picture with our results, which show that the observed constant [r-process/H] ratio in faint dwarf galaxies and one star unusually rich in r-process in the Sculptor galaxy agree well with this rarity of NSM events. Furthermore, we found that a large scatter in the abundance ratios of r-process elements to iron in the Galactic halo can be reproduced by a scheme that incorporates an assembly of various protogalactic fragments, in each of which r-process elements supplied by NSMs pervade the whole fragment while supernovae distribute heavy elements only inside the regions swept up by the blast waves. Our results demonstrate that NSMs occurring at Galactic rate of 12-23 Myr-1 are the main site of r-process elements, and we predict the detection of gravitational waves from NSMs at a high rate with upcoming advanced detectors.

Tsujimoto, T.; Shigeyama, T.

2014-05-01

54

Enrichment of a Microbial Culture Capable of Reductive Debromination of the Flame Retardant Tetrabromobisphenol-A, and Identification of the Intermediate Metabolites Produced in the Process  

Microsoft Academic Search

Tetrabromobisphenol-A is a reactive flame retardant used in the production of many plastic polymers. In previous research, it was demonstrated that anaerobic microorganisms from contaminated sediment debrominate tetrabromobisphenol-A to bisphenol-A, but an enrichment culture was not established. The current study was carried out to identify the intermediate metabolites in this process and to determine the factors facilitating enrichment of debrominating

Ziv Arbeli; Zeev Ronen

2003-01-01

55

Enrichment of the metallic components from waste printed circuit boards by a mechanical separation process using a stamp mill  

SciTech Connect

Printed circuit boards incorporated in most electrical and electronic equipment contain valuable metals such as Cu, Ni, Au, Ag, Pd, Fe, Sn, and Pb. In order to employ a hydrometallurgical route for the recycling of valuable metals from printed circuit boards, a mechanical pre-treatment step is needed. In this study, the metallic components from waste printed circuit boards have been enriched using a mechanical separation process. Waste printed circuit boards shredded to <10 mm were milled using a stamp mill to liberate the various metallic components, and then the milled printed circuit boards were classified into fractions of <0.6, 0.6-1.2, 1.2-2.5, 2.5-5.0, and >5.0 mm. The fractions of milled printed circuit boards of size <5.0 mm were separated into a light fraction of mostly non-metallic components and a heavy fraction of the metallic components by gravity separation using a zig-zag classifier. The >5.0 mm fraction and the heavy fraction were subjected to two-step magnetic separation. Through the first magnetic separation at 700 Gauss, 83% of the nickel and iron, based on the whole printed circuit boards, was recovered in the magnetic fraction, and 92% of the copper was recovered in the non-magnetic fraction. The cumulative recovery of nickel-iron concentrate was increased by a second magnetic separation at 3000 Gauss, but the grade of the concentrate decreased remarkably from 76% to 56%. The cumulative recovery of copper concentrate decreased, but the grade increased slightly from 71.6% to 75.4%. This study has demonstrated the feasibility of the mechanical separation process consisting of milling/size classification/gravity separation/two-step magnetic separation for enriching metallic components such as Cu, Ni, Al, and Fe from waste printed circuit boards.

Yoo, Jae-Min; Jeong, Jinki; Yoo, Kyoungkeun [Minerals and Materials Processing Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), 30 Gajeong-dong, Yuseong-gu, Daejeon 305-350 (Korea, Republic of); Lee, Jae-chun [Minerals and Materials Processing Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), 30 Gajeong-dong, Yuseong-gu, Daejeon 305-350 (Korea, Republic of)], E-mail: jclee@kigam.re.kr; Kim, Wonbaek [Minerals and Materials Processing Division, Korea Institute of Geoscience and Mineral Resources (KIGAM), 30 Gajeong-dong, Yuseong-gu, Daejeon 305-350 (Korea, Republic of)

2009-03-15

56

78 FR 33995 - Nuclear Proliferation Assessment in Licensing Process for Enrichment or Reprocessing Facilities  

Federal Register 2010, 2011, 2012, 2013

...requirements for advance notice and protection...shipments of specified materials. Further, appendix...prepared'' for the processing, use, or production...special fissionable material. In addition to...The statement that laser technology could...purify other kinds of materials such as SNM is...

2013-06-06

57

Enriching the Inoculation Construct: The Role of Critical Components in the Process of Resistance.  

ERIC Educational Resources Information Center

Tests effectiveness of inoculation treatments on 790 undergraduate students. Probes relationship between threat and involvement, their role in inoculation, and nature of cognitive processes triggered via inoculation. Suggests inoculation elicits threat, threat contributes to resistance, and resistance is most pronounced for more involved receivers…

Pfau, Michael; Tusing, Kyle James; Koerner, Ascan F.; Lee, Waipeng; Godbold, Linda C.; Penaloza, Linda J.; Yang, Violet Shu-Huei; Hong, Yah-Huei

1997-01-01

58

Enrichment, concentration and retention processes in relation to anchovy ( Engraulis ringens) eggs and larvae distributions in the northern Humboldt upwelling ecosystem  

Microsoft Academic Search

A Lagrangian model is used to simulate and quantify in the northern Humboldt upwelling ecosystem the processes of enrichment, concentration and retention, identified by Bakun [Bakun, A., 1996. Patterns in the ocean. Ocean processes and marine population dynamics. University of California Sea Grant, California, USA, in cooperation with Centro de Investigaciones Biologicas de Noroeste, La Paz, Baja California Sur, Mexico,

Christophe Lett; Pierrick Penven; Patricia Ayón; Pierre Fréon

2007-01-01

59

A laboratory model of a prebiotic, spontaneous, and continuous enantiomeric enrichment process.  

PubMed

Construction and operation of a laboratory model, which combines the lately discovered enantioenrichment method of the author (2007) with the sun-powered evaporative pumping process of Hsu and Siegenthaler (Sedimentology 12:11-25 1969), is described. The model operated continuously for 120 days before it was intentionally shut down, even though it could have continued. During that time it raised the enantiomeric excess of the test material by a factor of 3.6. Implications of these results on the origin of biohomochirality are discussed. PMID:23344885

Goldberg, Stanley I

2013-02-01

60

Geochemical diversity in S processes mediated by culture-adapted and environmental-enrichments of Acidithiobacillus spp.  

NASA Astrophysics Data System (ADS)

Coupled S speciation and acid generation resulting from S processing associated with five different microbial treatments, all primarily Acidithiobacillus spp. (i.e. autotrophic S-oxidizers) were evaluated in batch laboratory experiments. Microbial treatments included two culture-adapted strains, Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans, their consortia and two environmental enrichments from a mine tailings lake that were determined to be >95% Acidithiobacillus spp., by whole-cell fluorescent hybridization. Using batch experiments simulating acidic mine waters with no carbon amendments, acid generation, and S speciation associated with the oxidation of three S substrates (thiosulfate, tetrathionate, and elemental S) were evaluated. Aseptic controls showed no observable pH decrease over the experimental time course (1 month) for all three S compounds examined. In contrast, pH decreased in all microbial treatments from starting pH values of 4 to 2 or less for all three S substrates. Results show a non-linear relationship between the pH dynamics of the batch cultures and their corresponding sulfate concentrations, and indicate how known microbial S processing pathways have opposite impacts, ultimately on pH dynamics. Associated geochemical modeling indicated negligible abiogenic processes contributing to the observed results, indicating strong microbial control of acid generation extending over pH ranges from 4 to less than 2. However, the observed acid generation rates and associated S speciation were both microbial treatment and substrate-specific. Results reveal a number of novel insights regarding microbial catalysis of S oxidation: (1) metabolic diversity in S processing, as evidenced by the observed geochemical signatures in S chemical speciation and rates of acid generation amongst phylogenetically similar organisms (to the genus level); (2) consortial impacts differ from those of individual strain members; (3) environmental enrichments of Acidithiobacillus spp. catalyze different S reaction arrays than pure strain Acidithiobacillus spp.; and (4) microbial catalysis of S reactions involves significant disproportionation tied to substantial H + consumption, with the formation of as yet, poorly characterized intermediate S species, most likely polythionates and polysulfane monosulfonic acids that are thought to be involved in microbial S storage mechanisms.

Bernier, Luc; Warren, Lesley A.

2007-12-01

61

Optimization of an Enrichment process for Circulating tumor cells from the blood of Head and Neck Cancer patients through depletion of normal cells  

PubMed Central

The optimization of a purely negative depletion, enrichment process for circulating tumor cells, CTC's, in the peripheral blood of Head and Neck cancer patients is presented. The enrichment process uses a red cell lysis step followed by immunomagnetic labeling, and subsequent depletion, of CD45 positive cells. A number of relevant variables are quantified, or attempted to be quantified, which control the performance of the enrichment process. Six different immunomagnetic labeling combinations were evaluated as well as the significant difference in performance with respect to the blood source: buffy coats purchased from the Red Cross, fresh, peripheral blood from normal donors, and fresh peripheral blood from human cancer patients. After optimization, the process is able to reduce the number of normal blood cells in a cancer patient's blood from 4.05 × 109 to 8.04 × 103 cells/ml and still recover, on average, 2.32 CTC per ml of blood. For all of the cancer patient blood samples tested in which CTC were detected (20 out of 26 patients) the average recovery of CTCs was 21.7 per ml of blood, with a range of 282 to 0.53 CTC per ml of blood. Unlike a majority of other published studies, this study focused on quantifying as many factors as possible to facilitate both the optimization of the process as well as provide information for future performance comparisons. The authors are not aware any other reported study which has achieved the performance reported here (a 5.76 log10) in a purely negative enrichment mode of operation. Such a mode of operation of an enrichment process provides significant flexibility in that it has no bias with respect to what attributes define a CTC; thereby allowing the researcher or clinician to use any maker they choose to define whether the final, enrich product contains CTC's or other cell type relevant to the specific question (i.e. does the CTC have predominately epithelia or mesenchymal characteristics?).

Yang, Liying; Lang, James C.; Balasubramanian, Priya; Jatana, Kris R.; Schuller, David; Agrawal, Amit; Zborowski, Maciej; Chalmers, Jeffrey J.

2014-01-01

62

Development of LEU (Low Enriched Uranium) Targets for (99)Mo Production and Their Chemical Processing Status, 1989.  

National Technical Information Service (NTIS)

Most of the world's supply of (99m)Tc for medical purposes is currently produced from (99)Mo derived from the fissioning of high enriched uranium (HEU). Substitution of low enriched uranium (LEU) silicide fuel for the HEU alloy and aluminide fuels used in...

G. F. Vandegrift J. D. Kwok D. B. Chamberlain J. C. Hoh E. W. Streets

1989-01-01

63

Geochemistry of near-EPR seamounts: importance of source vs. process and the origin of enriched mantle component  

Microsoft Academic Search

Niu and Batiza [Earth Planet. Sci. Lett. 148 (1997) 471–483] show that lavas from the seamounts on the flanks of the East Pacific Rise (EPR) between 5° and 15°N vary from extremely depleted tholeiites to highly enriched alkali basalts. The extent of depletion and enrichment exceeds the known range of seafloor lavas in terms of the abundances and ratios of

Yaoling Niu; Marcel Regelous; Immo J. Wendt; Rodey Batiza; Mike J. O’Hara

2002-01-01

64

Code RED (Remediation and Enrichment Days): The Complex Journey of a School and University Partnership's Process to Increase Mathematics Achievement  

ERIC Educational Resources Information Center

This study examined a focused remediation and enrichment effort among school and university faculty to affect the mathematics achievement of a group of third-grade students in a Title I elementary school. A total of 87 students participated in the Code RED (Remediation and Enrichment Days) Project. During the Code RED Project, student assessment…

Moyer, Patricia S.; Dockery, Kim; Jamieson, Spencer; Ross, Julie

2007-01-01

65

In situ reduction of hexavalent chromium in alkaline soils enriched with chromite ore processing residue  

PubMed

In investigating chromium sites in New Jersey, it has been observed that an organic-rich 0.5- to 4-foot-thick layer of decayed vegetation (locally known as "meadowmat") underlying the chromium-containing material acts as a natural barrier to the migration of Cr(VI). The groundwater in a sand layer directly beneath the meadowmat has been shown to contain low or nondetectable levels of chromium. The meadowmat is under highly reduced conditions due to bacterial activity associated with the organic material. Based on the observed ability of the meadowmat to reduce Cr(VI) to Cr(III), the feasibility of in situ reduction of Cr(VI) to Cr(III) at chromite ore processing residue (COPR) sites was investigated in biologically-active, laboratory-scale test columns. COPR typically has a high pH (in excess of 12) and may contain total chromium concentrations as high as 70,000 mg/kg. Experimental results demonstrated that the addition of a mineral acid (to lower the pH to between 7.0 and 9.5) and a bacteria-rich organic substrate (fresh manure) resulted in the reduction of Cr(VI) to the less toxic and less mobile trivalent form. Pore water Cr(VI) was reduced from approximately 800 mg/L to less than 0.05 mg/L over a period of eight months. This is less than the U.S. Environmental Protection Agency's (EPA) Maximum Contaminant Level (MCL) for chromium in drinking water of 0.1 mg/L. Solid phase Cr(VI) concentrations decreased from approximately 2,000 mg/kg to less than 10 mg/kg in the columns over a period of 11 months while the total chromium concentrations remained unchanged. Toxicity Characteristic Leaching Procedure (TCLP) extract from the treated columns met the regulatory limit of 5 mg/L of Cr, whereas the untreated samples had TCLP extract concentrations greater than 40 mg/L. This study demonstrated the potential applicability of in situ reduction to soils contaminated with Cr(VI) by adjusting the pH to between 7.0 and 9.5 and mixing in a bacteria-rich organic substrate. PMID:9846134

Higgins; Halloran; Dobbins; Pittignano

1998-11-01

66

In-Situ Measurements of Low Enrichment Uranium Holdup Process Gas Piping at K-25-Paper for Waste Management Symposia 2010 East Tennessee Technology Park, Oak Ridge, Tennessee.  

National Technical Information Service (NTIS)

This document is the final version of a paper submitted to the Waste Management Symposia, Phoenix, 2010, abstract BJC/OR-3280. The primary document from which this paper was condensed is In-Situ Measurement of Low Enrichment Uranium Holdup in Process Gas ...

B. Rasmussen

2010-01-01

67

Development of LEU (low enriched uranium) targets for sup 99 Mo production and their chemical processing status, 1989  

Microsoft Academic Search

Most of the world's supply of {sup 99m}Tc for medical purposes is currently produced from ⁹⁹Mo derived from the fissioning of high enriched uranium (HEU). Substitution of low enriched uranium (LEU) silicide fuel for the HEU alloy and aluminide fuels used in current target designs will allow equivalent ⁹⁹Mo yields with no change in target geometries. Substitution of uranium metal

G. F. Vandegrift; J. D. Kwok; D. B. Chamberlain; J. C. Hoh; E. W. Streets; S. Vogler; H. R. Thresh; R. F. Domagala; T. C. Wiencek; J. E. Matos

1989-01-01

68

Enrichment, concentration and retention processes in relation to anchovy ( Engraulis ringens) eggs and larvae distributions in the northern Humboldt upwelling ecosystem  

NASA Astrophysics Data System (ADS)

A Lagrangian model is used to simulate and quantify in the northern Humboldt upwelling ecosystem the processes of enrichment, concentration and retention, identified by Bakun [Bakun, A., 1996. Patterns in the ocean. Ocean processes and marine population dynamics. University of California Sea Grant, California, USA, in cooperation with Centro de Investigaciones Biologicas de Noroeste, La Paz, Baja California Sur, Mexico, 323 pp.] as being important for the survival and recruitment of early life stages of pelagic fish. The method relies on tracking the positions of particles within water velocity fields generated by a three-dimensional hydrodynamic model. Simple criteria for considering particles as participating to enrichment, concentration or retention are used to derive indices of the three processes. We analyse the spatial distribution of and seasonal variability in these indices. The results are discussed in relation to anchovy ( Engraulis ringens) eggs and larvae distributions off Peru, and to a comparable study conducted in the southern Benguela upwelling ecosystem.

Lett, Christophe; Penven, Pierrick; Ayón, Patricia; Fréon, Pierre

2007-01-01

69

Enriched Uranium  

NSDL National Science Digital Library

This Wikipedia website provides information about the various concentrations of uranium used for different applications. Topics include a brief description of the grades of uranium and methods of isotope separation. There are also links to other aspects of uranium enrichment and related information. This information lays the foundation for informed discussion about the potential of nuclear energy and the risks of nuclear proliferation.

Wikipedia

70

16. VIEW OF THE ENRICHED URANIUM RECOVERY SYSTEM. ENRICHED URANIUM ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. VIEW OF THE ENRICHED URANIUM RECOVERY SYSTEM. ENRICHED URANIUM RECOVERY PROCESSED RELATIVELY PURE MATERIALS AND SOLUTIONS AND SOLID RESIDUES WITH RELATIVELY LOW URANIUM CONTENT. URANIUM RECOVERY INVOLVED BOTH SLOW AND FAST PROCESSES. (4/4/66) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

71

La pedagogie du francais langue seconde: enrichissement d'un code et pratique en acte et en situation (Teaching French as a Second Language: Enrichment of a Code and Practice in Action and in Situations)  

ERIC Educational Resources Information Center

Discusses the teaching of French as a second language to Tunisian students. The emphasis is on practicing "in action" and "in situations" so that the language is taught as a means of communication and not as an end in itself. (Text is in French.) (AM)

Blondel, Anne-Marie

1975-01-01

72

Profile of World Uranium Enrichment Programs - 2007  

Microsoft Academic Search

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

Laughter; Mark D

2007-01-01

73

Profile of World Uranium Enrichment Programs-2009  

Microsoft Academic Search

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

Laughter; Mark D

2009-01-01

74

Enrichment of Rare Earth Elements during magmatic and post-magmatic processes: a case study from the Loch Loyal Syenite Complex, northern Scotland  

NASA Astrophysics Data System (ADS)

Concern about security of supply of critical elements used in new technologies, such as the Rare Earth Elements (REE), means that it is increasingly important to understand the processes by which they are enriched in crustal settings. High REE contents are found in syenite-dominated alkaline complexes intruded along the Moine Thrust Zone, a major collisional zone in north-west Scotland. The most northerly of these is the Loch Loyal Syenite Complex, which comprises three separate intrusions. One of these, the Cnoc nan Cuilean intrusion, contains two mappable zones: a Mixed Syenite Zone in which mafic melasyenite is mixed and mingled with leucosyenite and a Massive Leucosyenite Zone. Within the Mixed Syenite Zone, hydrothermal activity is evident in the form of narrow altered veins dominated by biotite and magnetite; these are poorly exposed and their lateral extent is uncertain. The REE mineral allanite is relatively abundant in the melasyenite and is extremely enriched in the biotite-magnetite veins, which have up to 2 % total rare earth oxides in bulk rock analyses. An overall model for development of this intrusion can be divided into three episodes: (1) generation of a Light Rare Earth Element (LREE)-enriched parental magma due to enrichment of the mantle source by subduction of pelagic carbonates; (2) early crystallisation of allanite in melasyenite, due to the saturation of the magma in the LREE; and (3) hydrothermal alteration, in three different episodes identified by petrography and mineral chemistry, generating the intense enrichment of REE in the biotite-magnetite veins. Dating of allanite and titanite in the biotite-magnetite veins gives ages of c. 426 Ma, overlapping with previously published crystallisation ages for zircon in the syenite.

Walters, A. S.; Goodenough, K. M.; Hughes, H. S. R.; Roberts, N. M. W.; Gunn, A. G.; Rushton, J.; Lacinska, A.

2013-10-01

75

Final report on the project entitled: Highly Preheated Combustion Air System with/without Oxygen Enrichment for Metal Processing Furnaces  

SciTech Connect

This work develops and demonstrates a laboratory-scale high temperature natural gas furnace that can operate with/without oxygen enrichment to significantly improve energy efficiency and reduce emissions. The laboratory-scale is 5ft in diameter & 8ft tall. This furnace was constructed and tested. This report demonstrates the efficiency and pollutant prevention capabilities of this test furnace. The project also developed optical detection technology to control the furnace output.

Arvind Atreya

2007-02-16

76

Conversion of Methane to Hydrogen in a Reversible Flow Reactor in the Process of Filtration Combustion of Fuel Mixtures Enriched with Oxygen  

NASA Astrophysics Data System (ADS)

This paper considers the process of partial oxidation of methane to syngas in a reversible flow reactor in the process of filtration combustion of fuel mixtures enriched with oxygen in an inert porous medium. Experimental studies have been made of the influence of the volume concentration of oxygen in the initial fuel mixture on the basic parameters of the conversion process — the maximum temperature in the combustion wave and the composition of reaction products. Investigations have been carried out for fuel mixtures having different calorific values under the same filtration conditions. It has been shown that the addition of oxygen to the initial methane-air mixture permits increasing considerably the efficiency of the conversion process.

Dmitrenko, Yu. M.; Klyovan, R. A.

2013-11-01

77

Phytoplankton processes during a mesoscale iron enrichment in the NE subarctic Pacific: Part I—Biomass and assemblage  

NASA Astrophysics Data System (ADS)

We report results from the Subarctic Ecosystem Response to Iron Enrichment Study (SERIES) experiment in waters of the NE subarctic Pacific in which a large scale iron (Fe) enrichment lead to a shift in the phytoplankton assemblage from pico- and nanophytoplankton to one dominated by large diatoms. The phytoplankton response to the added Fe was monitored for 26 days following two infusions into a 77 km 2 patch of seawater. During the course of the experiment, the resulting algal bloom was constrained within the upper 30 m and spread to a region measuring over 1000 km 2. Phytoplankton chlorophyll a (chl a) increased from 0.3 mg m -3 to a peak of 6.3 mg m -3 18 days after the initial addition of Fe. Water-column integrated chl a was enhanced 8-fold, reaching a maximum of 114 mg m -2 on day 17. The resulting bloom is described in two ecological phases based on dominant phytoplankton groups. In Phase I, which encompassed the initial infusion up to day 10, all size-fractions (0.2-2, 2-20 and >20 ?m) increased in biomass as indicated by chl a, contributing to a surface standing stock of 2 mg m -3. In Phase II, from days 10 to 18, the bloom was dominated by microphytoplankton (>20 ?m), with a concomitant decrease in phytoplankton <20 ?m. Microphytoplankton, which initially accounted for 25% of the phytoplankton biomass and increased by a factor of 50, consisted primarily of the pennate diatom genera, Pseudo-nitzschia, Neodenticula and Thalassiothrix and the centric diatom genera, Chaetoceros, Rhizosolenia, and Proboscia. Particulate carbon-to-chl a (PC: chl a) ratios for large cells (?5 ?m) decreased 5-fold by day 18, indicative of enhanced cellular chl a content and increased phytoplankton contributions to PC. Pennate diatoms were most abundant in the patch, although when converted to biovolume, centric diatoms contributed larger amounts of algal carbon (C) to the bloom. A rapid decline in chl a on day 19 marked the onset of bloom decline. The magnitude, duration and composition of the phytoplankton response to the Fe enrichment clearly depicted a major shift in the structure of the algal assemblage and increased C export potential.

Marchetti, Adrian; Sherry, Nelson D.; Kiyosawa, Hiroshi; Tsuda, Atsushi; Harrison, Paul J.

2006-10-01

78

31 CFR 540.316 - Uranium enrichment.  

Code of Federal Regulations, 2013 CFR

...ASSETS CONTROL REGULATIONS General Definitions § 540.316 Uranium enrichment. The term uranium enrichment means the process of increasing the concentration of the isotope U235 relative to that of the isotope...

2013-07-01

79

Self-Enrichment Through Teaching.  

ERIC Educational Resources Information Center

Following a brief discussion of the "occupational diseases" of teaching are some questions which teachers can ask themselves to help define for themselves how they might use the teaching process to enrich themselves as people. (KC)

Pine, Gerald J.; Boy, Angelo V.

1979-01-01

80

Preliminary study of sources and processes of enrichment of manganese in water from University of Rhode Island supply wells  

USGS Publications Warehouse

Concentrations of dissolved manganese have increased from 0.0 to as much as 3.3 mg/liter over a period of years in closely spaced University of Rhode Island supply wells. The wells tap stratified glacial deposits and derive part of their water from infiltration from a nearby river-pond system. The principal sources of the manganese seem to be coatings of oxides and other forms of manganese on granular aquifer materials and organic-rich sediments on the bottom of the pond and river. Chemical analyses of water from an observation well screened from 3 to 5 feet below the pond bottom indicate that infiltration of water through organic-rich sediments on the pond bottom is the likely cause of manganese enrichment in the well supplies. After passing through the organic layer, the water contains concentrations of manganese as high as 1.2 mg/liter. Manganese in water in concentrations that do not cause unpleasant taste is not regarded to be toxicologically significant. However, concentrations in excess of a few tenths of a milligram per liter are undesirable in public supplies and in many industrial supplies. Brown and others (21970) note that waters containing manganese in concentrations less than 0.1 mg/liter seldom prove troublesome, but that those containing more than 0.5 mg/liter may form objectionable deposits on cooked food, laundry, and plumbing fixtures. The U.S. Public health Service (1962) recommends that the concentrations of manganese in drinking and culinary water not exceed 0.05 mg/liter. (Woodard-USGS)

Silvey, William Dudley; Johnston, Herbert E.

1977-01-01

81

Ultrathin (5 nm) SiGe-On-Insulator with high compressive strain (-2 GPa): From fabrication (Ge enrichment process) to in-depth characterizations  

NASA Astrophysics Data System (ADS)

300 mm ultrathin Silicon-On-Insulator (SOI) wafers with SiGe/Si stacks on top were used as pre-structures for the fabrication of 5 nm thick SiGe-On-Insulator (SGOI) substrates obtained by the Ge enrichment technique. Those substrates will be used as the channel of advanced Fully Depleted (FD) p-type Metal Oxide Semiconductor Field Effect Transistors (pMOSFET). We present in the first part the successful fabrication of 5 nm SGOI wafers. Various characterization techniques are used to investigate the Ge profile and the final strain in the fabricated 5 nm Si0.7Ge0.3 film. Secondary Ions Mass Spectrometry (SIMS) and Scanning Transmission Electron Microscopy (STEM) clearly show that the Ge content is very homogeneous (xGe = 30 ± 1%) in the SiGe layer. Raman spectroscopy and High Angle Annular Dark Field (HAADF) STEM both confirm that the 5 nm thick SiGe film is compressively strained (-2 GPa). The second part is dedicated to the sensitivity of the Ge enrichment process (based on numerical modelling). We investigate the impact of single and combined fluctuations of the pre-structure parameters (TSi, TSiGe,0, xGe,0) on the final SiGe layer (TSiGe, xGe).

Glowacki, F.; Le Royer, C.; Morand, Y.; Pédini, J.-M.; Denneulin, T.; Cooper, D.; Barnes, J.-P.; Nguyen, P.; Rouchon, D.; Hartmann, J.-M.; Gourhant, O.; Baylac, E.; Campidelli, Y.; Barge, D.; Bonnin, O.; Schwarzenbach, W.

2014-07-01

82

Expensive Enrichment  

ERIC Educational Resources Information Center

This article presents an economic analysis of the nuclear fuel reprocessing industry. It indicates that while environmental safety devices have improved the working conditions, they have also added ever-increasing costs to this necessary process. (MA)

Resnikoff, Marvin

1975-01-01

83

Influence of fine process particles enriched with metals and metalloids on Lactuca sativa L. leaf fatty acid composition following air and/or soil-plant field exposure.  

PubMed

We investigate the effect of both foliar and root uptake of a mixture of metal(loid)s on the fatty acid composition of plant leaves. Our objectives are to determine whether both contamination pathways have a similar effect and whether they interact. Lactuca sativa L. were exposed to fine process particles enriched with metal(loid)s in an industrial area. Data from a first experiment were used to conduct an exploratory statistical analysis which findings were successfully cross-validated by using the data from a second one. Both foliar and root pathways impact plant leaf fatty acid composition and do not interact. Z index (dimensionless quantity), weighted product of fatty acid concentration ratios was built up from the statistical analyses. It provides new insights on the mechanisms involved in metal uptake and phytotoxicity. Plant leaf fatty acid composition is a robust and fruitful approach to detect and understand the effects of metal(loid) contamination on plants. PMID:23694728

Schreck, Eva; Laplanche, Christophe; Le Guédard, Marina; Bessoule, Jean-Jacques; Austruy, Annabelle; Xiong, Tiantian; Foucault, Yann; Dumat, Camille

2013-08-01

84

Progress in developing processes for converting ⁹⁹Mo production from high- to low-enriched uranium1998  

Microsoft Academic Search

During 1998, the emphasis of our activities was focused mainly on target fabrication. Successful conversion requires a reliable irradiation target; the target being developed uses thin foils of uranium metal, which can be removed from the target hardware for dissolution and processing. This paper describes successes in (1) improving our method for heat-treating the uranium foil to produce a random-small

C. Conner; M. W. Liberatore; A. Mutalib; J. Sedlet; D. Walker; G F. Vandegrift

1998-01-01

85

Improved automated bone marrow processing and enrichment of CD34+ cells by a large-volume apheresis procedure.  

PubMed

We investigated the efficacy of bone marrow (bm) processing by a large-volume apheresis procedure using a self constructed sixfold collection bag system for sequential cell collection and analysis for 5 pediatric patients. Quantitation of leukocytes (WBC), CD34+ cells and colony-forming cells (CFU-GM) within the single bags showed a relative time-dependent decrease of all cell fractions during leukapheresis, whereas the relative amount of mononuclear cells (MNC) droped only slightly. At the same time the large volume apheresis (6 x original bm-volume) clearly enhanced the absolute yield of CD34+ cells compared to the standard procedure (3 x bm-volume) for more than 20%. We conclude that large-volume apheresis for bm processing is an efficient technique to improve the yields of progenitor cells. PMID:8865944

Cassens, U; Garritsen, H; Ernst, R; Jürgens, H; Sibrowski, W

1996-01-01

86

Chemical Looping Gasification of Biomass for Hydrogen Enriched Gas Production with In-Process Carbon-Dioxide Capture  

NASA Astrophysics Data System (ADS)

The research presents an innovative idea of developing a continuous H2 production process employing fluidized bed technology from agricultural biomass with in-situ CO2 capture and catalyst regeneration. Novelty of the process lies in the generation of relatively pure H2 from biomass with CO2 as a by-product using steam as the gasifying agent. Another unique feature of the process is internal regeneration of the catalyst, fouled in the gasifier. Thus, the technology will serve the twin purpose of regenerating the catalyst, and generation of N2 free H2 and CO2. The work also reports the experimental results conducted in a batch type fluidized bed steam gasifier using CaO as the catalyst. A 71% concentration of H2 and nearly 0 concentration of CO2 were achieved in the product gas when sawdust was used as the feedstock. In a separate test using a circulating fluidized bed reactor as the regenerator, a 40 % regeneration of CaO was also achieved at a calcination temperature of 800°C.

Dutta, Animesh; Aeharya, Bishnu; Basu, Prabir

87

Effects of dietary enrichment with n-3 fatty acids on the quality of raw and processed breast meat of high and low growth rate chickens.  

PubMed

1. The enrichment of raw poultry meat with n-3 fatty acids (n-3 FA) has been investigated in detail, particularly in high growth rate genotype standard broiler chickens, whereas low growth rate genotype Label Rouge chickens have received less attention. With the increased development of processed poultry products, it is necessary to ensure that the nutritional and sensory quality of meat enriched with n-3 FA is not affected by processing. 2. Two experiments were undertaken for this purpose. In the first experiment, 696 male Ross 708 chickens were reared under standard conditions, and in the second, 750 male JA 657 chickens were reared under Label Rouge conditions. All birds received the same starting and growing diets containing palm and soya oils in each experiment. Birds were distributed into three groups from 21 or 57 d of age for standard and Label Rouge chickens, respectively, and given a control, linseed oil or extruded linseed diet. Diets were also supplemented with vitamin E (100-200 mg/kg). Birds were slaughtered at 56 or 84 d of age for standard and Label Rouge chickens, respectively. A total amount of 60 kg of breast meat from each group was processed into white cured-cooked meat. 3. The dietary treatment had no effect on the growth performance of chickens or meat yield. The use of extruded linseed or linseed oil only decreased the carcass fatness of the standard chickens but had no effect on the carcass fatness of Label Rouge chickens. The nutritional quality of raw and cured-cooked meat was improved (increased concentration of n-3 FA), whereas the technological quality of the meat (pH, juice loss after cold storage, susceptibility to oxidation, colour, processing yield and shear force value) and sensory quality of the processed products were not or slightly affected. 4. Linked to lower breast yield, to lower lipid content in breast meat and to higher slaughter age, Label Rouge chickens seemed to be less efficient for n-3 FA deposition in breast muscles than standard chickens. PMID:23647182

Baeza, E; Chartrin, P; Gigaud, V; Tauty, S; Meteau, K; Lessire, M; Berri, C

2013-01-01

88

Nutrient enrichment, phytoplankton algal growth, and estimated rates of instream metabolic processes in the Quinebaug River Basin, Connecticut, 2000-2001  

USGS Publications Warehouse

A consistent and pervasive pattern of nutrient enrichment was substantiated by water-quality sampling in the Quinebaug River and its tributaries in eastern Connecticut during water years 2000 and 2001. Median total nitrogen and total phosphorus concentrations exceeded the U.S. Environmental Protection Agency?s recently recommended regional ambient water-qual-ity criteria for streams (0.71 and 0.031 milligrams per liter, respectively). Maximum total phosphorus concentrations exceeded 0.1 milligrams per liter at nearly half the sampled locations in the Quinebaug River Basin. Elevated total nitrogen and total phosphorus concentrations were measured at all stations on the mainstem of the Quinebaug River, the French River, and the Little River. Nutrient enrichment was related to municipal wastewater point sources at the sites on the mainstem of the Quinebaug River and French River, and to agricultural nonpoint nutrient sources in the Little River Basin. Nutrient enrichment and favorable physical factors have resulted in excessive, nuisance algal blooms during summer months, particularly in the numerous impoundments in the Quinebaug River system. Phytoplankton algal density as high as 85,000 cells per milliliter was measured during such nuisance blooms in water years 2000 and 2001. Different hydrologic conditions during the summers of 2000 and 2001 produced very different seston algal populations. Larger amounts of precipitation sustained higher streamflows in the summer of 2000 (than in 2001), which resulted in lower total algal abundance and inhibited the typical algal succession from diatoms to cyanobacteria. Despite this, nearly half of all seston chlorophyll-a concentrations measured during this study exceeded the recommended regional ambient stream-water-quality criterion (3.75 micrograms per liter), and seston chlorophyll-a concentrations as large as 42 micrograms per liter were observed in wastewa-ter-receiving reaches of the Quinebaug River. Estimates of primary productivity and respiration obtained from diel dissolved oxygen monitoring and from light- and dark-bottle dissolved oxygen measurements demonstrated that instream metabolic processes are consistent with a seston-algae dominant system. The highest estimated maximum primary productivity rate was 1.72 grams of oxygen per cubic meter per hour at the Quinebaug River at Jewett City during September 2001. The observed extremes in diel dissolved oxygen concentrations (less than 5 milligrams per liter) and pH (greater than 9) may periodically stress aquatic organisms in the Quinebaug River Basin.

Colombo, Michael J.; Grady, Stephen J.; Todd Trench, Elaine C.

2004-01-01

89

Evaluation of processes controlling the geochemical constituents in deep groundwater in Bangladesh: spatial variability on arsenic and boron enrichment.  

PubMed

Forty-six deep groundwater samples from highly arsenic affected areas in Bangladesh were analyzed in order to evaluate the processes controlling geochemical constituents in the deep aquifer system. Spatial trends of solutes, geochemical modeling and principal component analysis indicate that carbonate dissolution, silicate weathering and ion exchange control the major-ion chemistry. The groundwater is dominantly of Na-Cl type brackish water. Approximately 17% of the examined groundwaters exhibit As concentrations higher than the maximum acceptable limit of 10 microg/L for drinking water. Strong correlation (R(2)=0.67) of Fe with dissolved organic carbon (DOC) and positive saturation index of siderite suggests that the reductive dissolution of Fe-oxyhydroxide in presence of organic matter is considered to be the dominant process to release high content of Fe (median 0.31 mg/L) in the deep aquifer. In contrast, As is not correlated with Fe and DOC. Boron concentration in the 26% samples exceeds the standard limit of 500 microg/L, for water intended for human consumption. Negative relationships of B/Cl ratio with Cl and boron with Na/Ca ratio demonstrate the boron in deep groundwater is accompanied by brackish water and cation exchange within the clayey sediments. PMID:20092941

Halim, M A; Majumder, R K; Nessa, S A; Hiroshiro, Y; Sasaki, K; Saha, B B; Saepuloh, A; Jinno, K

2010-08-15

90

Efficacy and kinetics of bone marrow processing and enrichment of haematopoietic progenitor cells (HPC) by a large-volume apheresis procedure.  

PubMed

We investigated the efficacy of bone marrow (BM) processing by an automated large-volume apheresis procedure (6 x original BM volume) in 10 paediatric and adult patients undergoing BM harvesting before myeloablative therapy. Volume-dependent kinetics during apheresis were analyzed by sequential collection of processed cells into a six-fold collection bag system with consecutive analysis of the single bags. BM processing resulted in an 83.3% (+/- 21) recovery of mononuclear cells (MNC), a 97.9% (+/- 1.1) reduction of erythrocytes (RBC) and a 87.7% (+/- 2.9) volume reduction. To determine volume-dependent kinetics of haematopoietic progenitor cell (HPC) enrichment during apheresis, leukocytes (WBC), mononuclear cells (MNC), CD34 cells and colony-forming cells (CFU-GM) were serially quantitated in subsequent collection bags. Large-volume BM processing significantly enhanced absolute yields of CD34+ cells (mean: 4.01 (+/- 2.81) x 10(6)/kg bw) and CFU-GM (mean: 1.92 (+/- 1.47) x 10(4)/kg bw) compared with the standard procedure (3 x BM volume) by 26.9% (+/- 10.9) and 27.2% (+/- 11.6), respectively. We concluded that large-volume apheresis for BM processing is an efficient technique significantly improving the yields of haematopoietic progenitor cells (HPC) without any relevant changes in the purity of the final product. Moreover, sequential collection and analysis of HPC represents a good model to investigate the volume-dependent kinetics and efficacy of BM processing. PMID:9134178

Cassens, U; Ostkamp-Ostermann, P; Garritsen, H; Kelsch, R; Ostermann, H; Kienast, J; Kiehl, M; Buechner, T; van de Loo, J; Juergens, H; Sibrowski, W

1997-04-01

91

Progress in developing processes for converting {sup 99}Mo production from high- to low-enriched uranium--1998.  

SciTech Connect

During 1998, the emphasis of our activities was focused mainly on target fabrication. Successful conversion requires a reliable irradiation target; the target being developed uses thin foils of uranium metal, which can be removed from the target hardware for dissolution and processing. This paper describes successes in (1) improving our method for heat-treating the uranium foil to produce a random-small grain structure, (2) improving electrodeposition of zinc and nickel fission-fragment barriers onto the foil, and (3) showing that these fission fragment barriers should be stable during transport of the targets following irradiation. A method was also developed for quantitatively electrodepositing uranium and plutonium contaminants in the {sup 99}Mo. Progress was also made in broadening international cooperation in our development activities.

Conner, C.

1998-10-28

92

Where does the carbon go? A model-data intercomparison of vegetation carbon allocation and turnover processes at two temperate forest free-air CO2 enrichment sites.  

PubMed

Elevated atmospheric CO2 concentration (eCO2 ) has the potential to increase vegetation carbon storage if increased net primary production causes increased long-lived biomass. Model predictions of eCO2 effects on vegetation carbon storage depend on how allocation and turnover processes are represented. We used data from two temperate forest free-air CO2 enrichment (FACE) experiments to evaluate representations of allocation and turnover in 11 ecosystem models. Observed eCO2 effects on allocation were dynamic. Allocation schemes based on functional relationships among biomass fractions that vary with resource availability were best able to capture the general features of the observations. Allocation schemes based on constant fractions or resource limitations performed less well, with some models having unintended outcomes. Few models represent turnover processes mechanistically and there was wide variation in predictions of tissue lifespan. Consequently, models did not perform well at predicting eCO2 effects on vegetation carbon storage. Our recommendations to reduce uncertainty include: use of allocation schemes constrained by biomass fractions; careful testing of allocation schemes; and synthesis of allocation and turnover data in terms of model parameters. Data from intensively studied ecosystem manipulation experiments are invaluable for constraining models and we recommend that such experiments should attempt to fully quantify carbon, water and nutrient budgets. PMID:24844873

De Kauwe, Martin G; Medlyn, Belinda E; Zaehle, Sönke; Walker, Anthony P; Dietze, Michael C; Wang, Ying-Ping; Luo, Yiqi; Jain, Atul K; El-Masri, Bassil; Hickler, Thomas; Wårlind, David; Weng, Ensheng; Parton, William J; Thornton, Peter E; Wang, Shusen; Prentice, I Colin; Asao, Shinichi; Smith, Benjamin; McCarthy, Heather R; Iversen, Colleen M; Hanson, Paul J; Warren, Jeffrey M; Oren, Ram; Norby, Richard J

2014-08-01

93

Exome sequencing by targeted enrichment.  

PubMed

This unit describes methods for targeted enrichment of the exon-coding portions of the genome using Agilent SureSelect Human All Exon 50 Mb and Roche Nimblegen SeqCap EZ Exome platforms. Each platform targets and enriches a large overlapping portion of the greater human exome. The protocols here describe the biochemical procedures used to enrich exomic DNA with each platform, including recommended modifications to the manufacturers' protocols. In addition, a brief description of the sequencing protocol and estimation of the needed amount of sequencing for each platform is included. Finally, a detailed analytical pipeline for processing the subsequent data is described. These protocols focus specifically on human exome sequencing platforms, but can be applied with some modification to other organisms and targeted enrichment approaches. PMID:23547016

Clark, Michael James; Chen, Rui; Snyder, Michael

2013-01-01

94

Novel process of fermenting black soybean [Glycine max (L.) Merrill] yogurt with dramatically reduced flatulence-causing oligosaccharides but enriched soy phytoalexins.  

PubMed

Black soybeans [Glycine max (L.) Merrill] were germinated under fungal stress with food grade R. oligosporus for 3 days and were homogenized and fermented with lactic acid bacteria (LAB) to produce soy yogurt. Fungal stress led to the generation of oxylipins [oxooctadecadienoic acids (KODES) isomers and their respective glyceryl esters] and glyceollins--a type of phytoalexins unique to soybeans. In soy yogurt, the concentrations of total KODES and total glyceollins were 0.678 mg/g (dry matter) and 0.953 mg/g, respectively. The concentrations of other isoflavones (mainly genistein and daidzein and their derivatives) in soy yogurt remained largely unchanged after the processes compared with the control soy yogurt. Germination of black soybean under fungal stress for 3 days was sufficient to reduce stachyose and raffinose (which cause flatulence) by 92 and 80%, respectively. With a pH value of 4.42, a lactic acid content of 0.262%, and a maximum viable cell count of 2.1 x 10 (8) CFU/mL in the final soy yogurt, soy milk from germinated soybeans under fungal stress was concluded to be a suitable medium for yogurt-making. The resulting soy yogurt had significantly altered micronutrient profiles with significantly reduced oligosaccharides and enriched glyceollins. PMID:18831591

Feng, Shengbao; Saw, Chin Lee; Lee, Yuan Kun; Huang, Dejian

2008-11-12

95

Efficiency of four secondary enrichment protocols in differentiation and isolation of Listeria spp. and Listeria monocytogenes from smoked fish processing chains.  

PubMed

Four secondary enrichment protocols (conventional methods: UVM II, Fraser 24 h and Fraser 48 h: Impedimetric method: Listeria electrical detection medium) were studied for their ability to isolate Listeria spp. and Listeria monocytogenes from fish and environmental samples collected along the processing chain of cold-smoked fish. From all methods, Listeria spp. and L. monocytogenes were respectively present in 56 and 34 of 315 samples analysed. Fraser broth incubated for 48 h gave the fewest false negative Listeria spp. results [4/56; (7.1%)], but concurrently only 15/34 (44.1%) samples were correctly identified as containing L. monocytogenes, Listeria electrical detection (LED) medium detected only 36/56 (64.3%) Listeria spp. positive samples. Despite this lower isolation rate, LED identified 20/34 (58.8%) L. monocytogenes positive samples correctly and gave fewer false positive results. The overall conclusion was that more than one isolation method is needed to accurately estimate L. monocytogenes contamination rates. PMID:10733247

Duarte, G; Vaz-Velho, M; Capell, C; Gibbs, P

1999-11-15

96

Biomass gasification and in-bed contaminants removal: performance of iron enriched olivine and bauxite in a process of steam/O2 gasification.  

PubMed

A modified Olivine, enriched in iron content (10% Fe/Olivine), and a natural bauxite, were tested in the in-bed reduction of tar and alkali halides (NaCl and KCl) released in a process of biomass steam/O(2) gasification. The tests were carried out at an ICBFB bench scale reactor under the operating conditions of: 855-890 °C, atmospheric pressure, 0.5 steam/biomass and 0.33 ER ratios. From the use of the two materials, a reduction in the contaminant contents of the fuel gas produced was found. For the alkali halides, a decrease up to 70%(wt) was observed for the potassium concentration, while for sodium, the reduction was found to be quite poor. For the organic content, compared to unmodified Olivine, the chromatographically determined total tar quantity showed a removal efficiency of 38%(wt). Moreover, regarding the particulate content a rough doubling in the fuel gas revealed a certain brittleness of the new bed material. PMID:22705523

Barisano, D; Freda, C; Nanna, F; Fanelli, E; Villone, A

2012-08-01

97

Enrichment of light hydrocarbon mixture  

DOEpatents

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.

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

2010-08-10

98

Enrichment of light hydrocarbon mixture  

DOEpatents

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.

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)

2011-11-29

99

Effect of Enriched (Complex) Environment on Nerve Conduction Velocity: New Data and Review of Implications for the Speed of Information Processing.  

ERIC Educational Resources Information Center

Results with 54 mice confirm that increased stimulation or usage, as would be provided by environmental enrichment (EE), increases peripheral nerve conduction velocity. These results suggest a role at the physiological level for EE (or deprivation) in affecting measured intelligence. (SLD)

Reed, T. Edward

1993-01-01

100

Environmental Enrichment: Aging and Memory  

PubMed Central

A decline in learning and memory is a feature of the normal aging process and associated with neurodegenerative diseases such as dementia and Alzheimer’s disease. Moreover, certain forms of dementia and memory loss are inevitable due to the normal aging process. The unavoidable effect of age on memory is an ongoing study, as the findings assist in identifying cortical functions of the brain. Histone acetylation is a mechanism in synaptic plasticity and a key function in learning and memory because changes within the process alter gene transcription and the quantity of synthesized proteins. Similar to histone acetylation, environmental enrichment has also been found to improve memory formation by stimulating synaptic plasticity. Through understanding the mechanisms by which environmental enrichment and histone acetylation interact in the brain and affect learning and memory, novel applications can be developed for therapeutic interventions to neurodegenerative diseases and aging.

Patel, Toral Rohit

2012-01-01

101

Evolution of Listeria populations in food samples undergoing enrichment culturing  

Microsoft Academic Search

The isolation of Listeria monocytogenes from food is carried out using a double enrichment. It is believed that the double enrichment can allow the overgrowth of Listeria innocua in samples where both species are present. In this study, we have evaluated the impact of overgrowth between Listeria species and strains during each step of the enrichment process. The effect of

Nathalie Gnanou Besse; Nelly Audinet; Annaëlle Kérouanton; Pierre Colin; Martin Kalmokoff

2005-01-01

102

Conversion of Molybdenum-99 production process to low enriched uranium: Neutronic and thermal hydraulic analyses of HEU and LEU target plates for irradiation in Pakistan Research Reactor-1  

NASA Astrophysics Data System (ADS)

Technetium-99m, the daughter product of Molybdenum-99 is the most widely needed radionuclide for diagnostic studies in Pakistan. Molybdenum-99 Production Facility has been established at PINSTECH. Highly enriched uranium (93% 235U) U/Al alloy targets have been irradiated in Pakistan Research Reactor-1 (PARR-1) for the generation of fission Mo-99, while basic dissolution technique is used for separation of Mo-99 from target matrix activity. In line with the international objective of minimizing and eventually eliminating the use of HEU in civil commerce, national and international efforts have been underway to shift the production of medical isotopes from HEU to LEU (LEU; <20% 235U enrichment) targets. To achieve the equivalent amount of 99Mo with LEU targets, approximately 5 times uranium is needed. LEU aluminum uranium dispersion target has been developed, which may replace existing HEU aluminum/uranium alloy targets for production of 99Mo using basic dissolution technique. Neutronic and thermal hydraulic calculations were performed for safe irradiation of targets in the core of PARR-1.

Mushtaq, Ahmad; Iqbal, Masood; Bokhari, Ishtiaq Hussain; Mahmood, Tayyab; Muhammad, Atta

2012-09-01

103

Enrichment Map - a Cytoscape app to visualize and explore OMICs pathway enrichment results  

PubMed Central

High-throughput OMICs experiments generate signals for millions of entities (i.e. genes, proteins, metabolites or any measurable biological entity) in the cell. In an effort to summarize and explore these signals, expression results are examined in the context of known pathways and processes, through enrichment analysis to generate a set of pathways and processes that is significantly enriched. Due to the high redundancy in annotation resources this often results in hundreds of sets. To facilitate the analysis of these results, we have developed the Enrichment Map app to visualize enrichments as a network. We have updated Enrichment Map to support Cytoscape 3, and have added additional features including new data formats and command line access.

Isserlin, Ruth; Merico, Daniele; Voisin, Veronique; Bader, Gary D.

2014-01-01

104

Laser and gas centrifuge enrichment  

NASA Astrophysics Data System (ADS)

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.

Heinonen, Olli

2014-05-01

105

Enriching the Catalog  

ERIC Educational Resources Information Center

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…

Tennant, Roy

2004-01-01

106

Science Student Enrichment Opportunities.  

ERIC Educational Resources Information Center

This document was developed with the intention of increasing California public school students' awareness of and participation in science-related enrichment activities. Some of the activities are intended for participation by individuals, while others are meant for teams of students. These annual events are listed in chronological order for a…

California State Dept. of Education, Sacramento.

107

ENRICHMENT--CLASSROOM CHALLENGE.  

ERIC Educational Resources Information Center

THIS MANUAL CONTAINS SUGGESTIONS FOR ENRICHMENT IN LANGUAGE ARTS, SOCIAL STUDIES, SCIENCE, ARITHMETIC, FOREIGN LANGUAGES, ART, AND MUSIC AT THE ELEMENTARY LEVEL AND IN ENGLISH, SOCIAL STUDIES, SCIENCE, MATHEMATICS, MODERN LANGUAGES AND LATIN, ART, AND MUSIC AT THE SECONDARY LEVEL. ADDITIONAL SECTIONS INCLUDE INFORMATION ON THE USE OF COMMUNITY…

GIBBONY, HAZEL L.

108

Economic Analysis. Enrichment.  

ERIC Educational Resources Information Center

A multimedia course in economic analysis was prepared for the United States Naval Academy. (ED 043 790 and ED 043 791 are the final reports of the project evaluation and development model.) This report presents enrichment segments for selected core segments in concept areas one and two, covering a spectrum of economic systems, the influence of…

Sterling Inst., Washington, DC. Educational Technology Center.

109

Enriching Number Knowledge  

ERIC Educational Resources Information Center

Exploring number systems of other cultures can be an enjoyable learning experience that enriches students' knowledge of numbers and number systems in important ways. It helps students deepen mental computation fluency, knowledge of place value, and equivalent representations for numbers. This article describes how the author designed her…

Mack, Nancy K.

2011-01-01

110

U. S. forms uranium enrichment corporation  

SciTech Connect

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.

Seltzer, R.

1993-07-12

111

Advanced Neutron Source enrichment study  

Microsoft Academic Search

A study has been performed of the impact on performance of using low-enriched uranium (20% ²³⁵U) or medium-enriched uranium (35% ²³⁵U) as an alternative fuel for the Advanced Neutron Source, which was initially designed to use uranium enriched to 93% ²³⁵U. Higher fuel densities and larger volume cores were evaluated at the lower enrichments in terms of impact on neutron

R. A. Bari; H. Ludewig

1996-01-01

112

Advanced Neutron Source enrichment study  

Microsoft Academic Search

A study has been performed of the impact on performance of using low enriched uranium (20% ²³⁵U) or medium enriched uranium (35% ²³⁵U) as an alternative fuel for the Advanced Neutron Source, which is currently designed to use uranium enriched to 93% ²³⁵U. Higher fuel densities and larger volume cores were evaluated at the lower enrichments in terms of impact

R. A. Bari; H. Ludewig

1994-01-01

113

Organic wheatgrass as environmental enrichment.  

PubMed

Environmental enrichment must be provided for the various animal species that are housed in laboratory animal facilities. Wheatgrass can be used as a natural form of enrichment that requires minimal preparation and effort. Wheatgrass is appropriate enrichment for cats, rabbits, guinea pigs, rodents and birds. PMID:20164947

Brown, Cyndi

2010-03-01

114

Parents as Partners in Art Education Enrichment  

ERIC Educational Resources Information Center

The author describes a parent art program, how it works, and ways to implement it. She emphasizes the strengths of parent programs as a way to support and enrich existing arts education, not as a replacement. Hansen describes the art kit--the adult's teaching resource--and the basic four-part process: presentation, demonstration, an art activity,…

Hansen, Laurie

2008-01-01

115

KEA: kinase enrichment analysis  

PubMed Central

Motivation: Multivariate experiments applied to mammalian cells often produce lists of proteins/genes altered under treatment versus control conditions. Such lists can be projected onto prior knowledge of kinase–substrate interactions to infer the list of kinases associated with a specific protein list. By computing how the proportion of kinases, associated with a specific list of proteins/genes, deviates from an expected distribution, we can rank kinases and kinase families based on the likelihood that these kinases are functionally associated with regulating the cell under specific experimental conditions. Such analysis can assist in producing hypotheses that can explain how the kinome is involved in the maintenance of different cellular states and can be manipulated to modulate cells towards a desired phenotype. Summary: Kinase enrichment analysis (KEA) is a web-based tool with an underlying database providing users with the ability to link lists of mammalian proteins/genes with the kinases that phosphorylate them. The system draws from several available kinase–substrate databases to compute kinase enrichment probability based on the distribution of kinase–substrate proportions in the background kinase–substrate database compared with kinases found to be associated with an input list of genes/proteins. Availability: The KEA system is freely available at http://amp.pharm.mssm.edu/lib/kea.jsp Contact: avi.maayan@mssm.edu

Lachmann, Alexander; Ma'ayan, Avi

2009-01-01

116

Gene expression profiles of spleen, liver, and head kidney in turbot (Scophthalmus maximus) along the infection process with Philasterides dicentrarchi using an immune-enriched oligo-microarray.  

PubMed

We evaluated the expression profiles of turbot in spleen, liver, and head kidney across five temporal points of the Philasterides dicentrarchi infection process using an 8x15K Agilent oligo-microarray. The microarray included 2,176 different fivefold replicated gene probes designed from a turbot 3' sequenced EST database. We were able to identify 221 differentially expressed (DE) genes (8.1% of the whole microarray), 113 in spleen, 83 in liver, and 90 in head kidney, in at least 1 of the 5 temporal points sampled for each organ. Most of these genes could be annotated (83.0%) and functionally categorized using GO terms (69.1%) after the additional sequencing of DE genes from the 5' end. Many DE genes were related to innate and acquired immune functions. A high proportion of DE genes were organ-specific (70.6%), although their associated GO functions showed notable similarities in the three organs. The most striking difference in functional distribution was observed between the up- and downregulated gene groups. Upregulated genes were mostly associated to immune functions, while downregulated ones mainly involved metabolism-related genes. Genetic response appeared clustered in a few groups of genes with similar expression profiles along the temporal series. The information obtained will aid to understand the turbot immune response and will specifically be valuable to develop strategies of defense to P. dicentrarchi to achieve more resistant broodstocks for turbot industry. PMID:22367415

Pardo, Belén G; Millán, Adrián; Gómez-Tato, Antonio; Fernández, Carlos; Bouza, Carmen; Alvarez-Dios, José Antonio; Cabaleiro, Santiago; Lamas, Jesús; Leiro, José M; Martínez, Paulino

2012-10-01

117

Progress in alkaline peroxide dissolution of low-enriched uranium metal and silicide targets.  

National Technical Information Service (NTIS)

This paper reports recent progress on two alkaline peroxide dissolution processes: the dissolution of low-enriched uranium metal and silicide (U(sub 3)Si(sub 2)) targets. These processes are being developed to substitute low-enriched for high-enriched ura...

L. Chen D. Dong B. A. Buchholz G. F. Vandegrift D. Wu

1996-01-01

118

Thermal breeder fuel enrichment zoning  

DOEpatents

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.

Capossela, Harry J. (Schenectady, NY); Dwyer, Joseph R. (Albany, NY); Luce, Robert G. (Schenectady, NY); McCoy, Daniel F. (Latham, NY); Merriman, Floyd C. (Rotterdam, NY)

1992-01-01

119

Work Enrichment for Academic Libraries.  

ERIC Educational Resources Information Center

Explores important quality of work life strategy--job redesign--and discusses job enlargement and job enrichment. A case study of academic library personnel demonstrates how introduction of automated systems at University of California, Berkeley led to restructuring and enrichment of jobs. References and list of selected resources are appended.…

Martell, Charles; Untawale, Mercedes

1983-01-01

120

AVLIS enrichment of medical isotopes  

Microsoft Academic Search

Under the Sponsorship of the United states Enrichment Corporation (USEC), we are currently investigating the large scale separation of several isotopes of medical interest using atomic vapor isotope separation (AVLIS). This work includes analysis and experiments in the enrichment of thallium 203 as a precursor to the production of thallium 201 used in cardiac imaging following heart attacks, on the

C. A. Haynam; K. F. Scheibner; R. C. Stern; E. F. Worden

1996-01-01

121

ENRICHMENT OF OBO ONTOLOGIES  

PubMed Central

This paper describes a frame-based integration of the three GO subontologies, the Chemicals of Biological Interest ontology (ChEBI), and the Cell Type Ontology (CTO) in which relationships between elements of the ontologies are modeled in a way that better captures the relational semantics between biological concepts represented by the terms, rather than between the terms themselves, than previous frame-based efforts. We also describe a methodology for creating suggested enriching assertions of the form (subject, relationship, object) by identifying patterns in GO terms, mapping these patterns and subpatterns to relationships, matching concepts to these patterns and subpatterns, and integrating these assertions into the ontologies. Using this methodology, a large number of reliable assertions linking previously unlinked OBO terms using a wide variety of specific, hierarchically arranged relationships were created: A predicted assertion was made for 62% of GO terms that matched one of 31 patterns, and 97% of these predicted assertions were assessed to be valid; a further 429 assertions (corresponding to 6% of the matching terms) were manually created, resulting in an initial set of 4,497 assertions. Furthermore, this methodology programmatically integrates assertions into a base ontology such that each assertion is fully consistent with respect to higher (i.e., more general) relevant class and slot levels. Such an integration is absent from previous compositional efforts, and we argue its necessity for the creation of coherent biological ontologies when linking previously unlinked terms.

Bada, Michael; Hunter, Lawrence

2006-01-01

122

Avian antigen binding cells: enrichment methods.  

PubMed

Data are presented comparing different methods for the fractionation and enrichment, respectively, of specific antigen binding lymphoid cells from immunized chickens. The bovine serum albumin (BSA) anti-BSA system was chosen as a model. To enrich avian antigen binding cells (ABC) from a mixture of chicken peripheral blood and spleen lymphocytes 3 different methods were used: (1) separation of cells forming rosettes with antigen-coated sheep red blood cells (SRBC) from non-rosetting cells by density centrifugation; (2) isolation of ABC by their specific adherence to antigen bound to immunoadsorptive surfaces (gelatin, plastics); (3) column affinity chromatography with antigen-coated agarose, cross-linked dextran for plastic beads. The most efficient method was column affinity chromatography with antigen-coated polyacrylamide beads which affords up to 12-fold enrichment of ABC. Both the other methods are also suitable for separation and enrichment of specific ABC but can only with difficulty be adapted for processing the large numbers of cells which would be necessary, e.g., for in vivo transfer studies. PMID:422853

Wolf, H; Gattringer, C; Wick, G

1979-01-01

123

Uranium enrichment export control guide: Gaseous diffusion  

SciTech Connect

This document was prepared to serve as a guide for export control officials in their interpretation, understanding, and implementation of export laws that relate to the Zangger International Trigger List for gaseous diffusion uranium enrichment process components, equipment, and materials. Particular emphasis is focused on items that are especially designed or prepared since export controls are required for these by States that are party to the International Nuclear Nonproliferation Treaty.

Not Available

1989-09-01

124

Oxygen-enriched air for MHD power plants  

NASA Technical Reports Server (NTRS)

Cryogenic air-separation process cycle variations and compression schemes are examined. They are designed to minimize net system power required to supply pressurized, oxygen-enriched air to the combustor of an MHD power plant with a coal input of 2000 MWt. Power requirements and capital costs for oxygen production and enriched air compression for enrichment levels from 13 to 50% are determined. The results are presented as curves from which total compression power requirements can be estimated for any desired enrichment level at any delivery pressure. It is found that oxygen enrichment and recuperative heating of MHD combustor air to 1400 F yields near-term power plant efficiencies in excess of 45%. A minimum power compression system requires 167 MW to supply 330 lb of oxygen per second and costs roughly 100 million dollars. Preliminary studies show MHD/steam power plants to be competitive with plants using high-temperature air preheaters burning gas.

Ebeling, R. W., Jr.; Cutting, J. C.; Burkhart, J. A.

1979-01-01

125

DETERMINATION OF REACTIVITY LIFETIME FOR LOW ENRICHMENT, LIGHT WATER MODERATED POWER REACTORS  

Microsoft Academic Search

This report dsscribes the effect that variation in enrichment and water-; to-metal ratio have on the reactivity lifetime of low enrichment water moderated ; thermal reactors. Sines both reactivity lifetime and enrichment have a ; significant effect upon reactor fuel costs, the variation in these costs is also ; discussed. The present high chemical processing and fabrication costs cause the

Graves; H. W. Jr

1954-01-01

126

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

Federal Register 2010, 2011, 2012, 2013

...AREVA Enrichment Services, LLC (Eagle Rock Enrichment Facility) December 17, 2010...enrichment facility--denoted as the Eagle Rock Enrichment Facility (EREF)--in Bonneville...www.nrc.gov/materials/fuel-cycle-fac/arevanc.html. These and...

2011-01-04

127

Centrifuge Enrichment: Benefits and Risks.  

National Technical Information Service (NTIS)

The President decided to use the new centrifuge technology instead of the proven diffusion technology for the uranium enrichment plant to be built at Portsmouth, Ohio. This report addresses the appropriateness of (1) substituting the new technology and (2...

1978-01-01

128

10 CFR Appendix G to Part 110 - Illustrative List of Plasma Separation Enrichment Plant Equipment and Components Under NRC Export...  

...2014-01-01 false Illustrative List of Plasma Separation Enrichment Plant Equipment...G to Part 110—Illustrative List of Plasma Separation Enrichment Plant Equipment...Licensing Authority Note: In the plasma separation process, a plasma...

2014-01-01

129

Material control and accounting requirements for uranium enrichment facilities  

SciTech Connect

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 {ge}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.

Ting, P. (Nuclear Regulatory Commission, Washington, DC (United States). Office of Nuclear Material Safety and Safeguards); Moran, B.W. (International Technology Programs Div., Martin Marietta Energy Systems, Inc., Oak Ridge, TN (US))

1991-01-01

130

Enabling Enrichment Analysis with the Human Disease Ontology  

PubMed Central

Advanced statistical methods used to analyze high-throughput data such as gene-expression assays result in long lists of “significant genes.” One way to gain insight into the significance of altered expression levels is to determine whether Gene Ontology (GO) terms associated with a particular biological process, molecular function, or cellular component are over- or under-represented in the set of genes deemed significant. This process, referred to as enrichment analysis, profiles a gene-set, and is widely used to make sense of the results of high-throughput experiments. Our goal is to develop and apply general enrichment analysis methods to profile other sets of interest, such as patient cohorts from the electronic medical record, using a variety of ontologies including SNOMED CT, MedDRA, RxNorm, and others. Although it is possible to perform enrichment analysis using ontologies other than the GO, a key pre-requisite is the availability of a background set of annotations to enable the enrichment calculation. In the case of the GO, this background set is provided by the Gene Ontology Annotations. In the current work, we describe: (i) a general method that uses hand-curated GO annotations as a starting point for creating background datasets for enrichment analysis using other ontologies; and (ii) a gene–disease background annotation set—that enables disease-based enrichment—to demonstrate feasibility of our method.

LePendu, Paea; Musen, Mark A.; Shah, Nigam H.

2012-01-01

131

Conversion and Evaluation of the University of Massachusetts Lowell Research Reactor From High-Enriched To Low-Enriched Uranium Fuel  

Microsoft Academic Search

The process for converting the University of Massachusetts Lowell Research Reactor (UMLRR) from high-enrichment uranium (HEU) fuel to low-enrichment uranium (LEU) fuel began in 1988. Several years of design reviews, computational modeling, and thermal hydraulic analyses resulted in a preliminary reference core design and configuration based on 20 standard, MTR-type, flat-plate, 19.75% enriched, uranium silicide (u3Si2) fuel elements. A final

Leo M. Bobek

2003-01-01

132

Conversion and Blending Facility highly enriched uranium to low enriched uranium as metal. Revision 1  

SciTech Connect

The mission of this Conversion and Blending Facility (CBF) will be to blend surplus HEU metal and alloy with depleted uranium metal to produce an 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. The blended LEU will be produced as a waste suitable for storage or disposal.

NONE

1995-07-05

133

Progress in alkaline peroxide dissolution of low-enriched uranium metal and silicide targets  

Microsoft Academic Search

This paper reports recent progress on two alkaline peroxide dissolution processes: the dissolution of low-enriched uranium metal and silicide (UâSiâ) targets. These processes are being developed to substitute low-enriched for high-enriched uranium in targets used for production of fission-product ⁹⁹Mo. Issues that are addressed include (1) dissolution kinetics of silicide targets, (2) ⁹⁹Mo lost during aluminum dissolution, (3) modeling of

L. Chen; D. Dong; B. A. Buchholz; G. F. Vandegrift; D. Wu

1996-01-01

134

Enrichment for Nonhuman Primates: Baboons.  

National Technical Information Service (NTIS)

This book serves as an introduction to the basic behavior and environmental enrichment of a specific species of nonhuman primates that are more commonly used in education, research and entertainment. In many ways, this book is meant to be a how to manual;...

L. Brent T. M. Butler

2005-01-01

135

Enrichment for Nonhuman Primates: Chimpanzees.  

National Technical Information Service (NTIS)

This book serves as an introduction to the basic behavior and environmental enrichment of a specific species of nonhuman primates that are more commonly used in education, research and entertainment. In many ways, this book is meant to be a how to manual;...

K. Baker

2005-01-01

136

Day Care Center Enrichment Program.  

ERIC Educational Resources Information Center

This guide to a West Virginia Department of Welfare project for upgrading the quality of day care centers throughout the state presents samples of the forms used in the program, accompanied by a brief description of the program's format, requirements and procedures. The Day Care Center Enrichment Program provides a monetary incentive for…

West Virginia State Dept. of Welfare, Charleston.

137

Simulations of Cosmic Chemical Enrichment  

Microsoft Academic Search

Using a new numerical model for cosmic chemical evolution, we study the influence of hypernova feedback on the star formation and metal enrichment history of the universe. For assumptions which produce plausible results in idealized collapse models of individual galaxies, our cosmological simulations of the standard Lambda cold dark matter (CDM) cosmology show a peak of the cosmic star formation

Chiaki Kobayashi; Volker Springel; Simon D. M. White

2007-01-01

138

Enrichment Tours in Physical Education.  

ERIC Educational Resources Information Center

Enrichment tours designed to heighten interest and enhance the breadth and depth of learning a lifetime sport are encouraged. A tour of the Florida Keys and Bahama Islands for sailing and diving taken by students from Mankato State University is described. (JMF)

McCarthy, Jean

1980-01-01

139

Enrichment of the Intracluster Medium  

Microsoft Academic Search

The relevance of galaxies of different luminosity and mass for the chemical enrichment of the intracluster medium (ICM) is analysed. For this purpose, I adopt the composite luminosity function of cluster galaxies from Trentham (1998), which exhibits a significant rise at the very faint end. The model -- adopting a universal Salpeter IMF -- is calibrated on reproducing the M-Fe

Daniel Thomas

1999-01-01

140

Enriched uranium recovery flowsheet improvements  

SciTech Connect

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, /sup 95/Zr, has been adequate, but excessive solvent degradation caused by the long phase contact times in the mixer-settlers has limited the /sup 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 /sup 95/Zr removal efficiencies. Feed solutions spiked with actual plant solutions were used. The /sup 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.

Holt, D L

1986-01-01

141

Magnesian andesites, Nb-enriched basalt-andesites, and adakites from late-Archean 2.7 Ga Wawa greenstone belts, Superior Province, Canada: implications for late Archean subduction zone petrogenetic processes  

NASA Astrophysics Data System (ADS)

Magnesian andesites (MA) occur with 'normal' tholeiitic to calc-alkaline basalt-andesite suites in four greenstone belts of the 2.7 Ga Wawa subprovince, Canada. Collectively, the magnesian andesites span ranges of SiO2=56-64 wt%, Mg-number=0.64-0.50, with Cr and Ni contents of 531-106 and 230-21 ppm, respectively. Relative to 'normal' andesites, the magnesian andesites form distinct trends on variation diagrams, with relatively high Th and LREE contents, uniform Yb over a range of MgO, more fractionated HREE, and lower Nb/Thpm and Nb/Lapm ratios. Niobium-enriched basalts and andesites (NEBA; Nb=7-16 ppm), and an Al-enriched rhyolite (adakite) suite are associated in space and time with the magnesian andesites. Nb-enriched basalts and andesites are characterized by high TiO2, P2O5, Th, and Zr contents, variably high Zr/Hf (36-44) ratios, and more fractionated HREE (Gd/Ybcn=1.3-4.1) compared to the 'normal' tholeiitic to calc-alkaline basalt-andesite suites. The adakite suite has the high Al (Al2O3=16-18 wt%), high La/Ybcn (21-43), and low Yb (0.4-1.2 ppm) of Archean tonalite-trondhjemite-granodiorite (TTG) suites and Cenozoic adakites, indicative of liquids derived mainly from slab melting. The basalt-andesite suites are not characterized by normal tholeiitic or calc-alkaline fractionation trends of major or trace elements. Rather, compositional trends can be accounted for by some combination of fractional crystallization and variable degrees of metasomatism of the source of basalt and/or andesites by adakitic liquids. The occurrence of magnesian andesites, Nb-enriched basalts/andesites, and adakites has been described from certain Phanerozoic arcs featuring shallow subduction of young and/or hot oceanic lithosphere. Adakites likely represent slab melts, magnesian andesites the product of hybridization of adakite liquids with mantle peridotite, and Nb-enriched basalts/andesites melts of the residue from hybridization. Geological similarities between the late-Archean Wawa greenstone belts and certain Cenozoic transpressional orogens with the MA-NEBA-adakite association suggest that subduction of young, hot oceanic lithosphere may have played an important role in the production of this arc-related association in the late Archean.

Polat, A.; Kerrich, R.

2001-02-01

142

Conversion and Blending Facility Highly enriched uranium to low enriched uranium as uranium hexafluoride. Revision 1  

SciTech Connect

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.

NONE

1995-07-05

143

Conversion and Blending Facility highly enriched uranium to low enriched uranium as oxide. Revision 1  

SciTech Connect

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.

NONE

1995-07-05

144

Enriching tortoises: assessing color preference.  

PubMed

Environmental enrichment is a principle that is used to enhance the quality of care for nonhuman animals in captivity. To achieve this, it is necessary to understand the animal's needs. This study focused on color preference to provide food stimuli as a source of environmental enrichment for the tortoise, Chelonoidis denticulata. During this study, the stimuli green-, blue-, yellow-, and red-colored bananas and plaster blocks were randomly offered to the tortoises. Analysis of the data showed that the tortoises had a preference for the stimuli dyed with colors red and yellow over the other presented colors. It was possible to conclude that presenting food in different colors stimulated the animals to evaluate their environment and make choices in relation to their color preference. Thus, this experiment introduced an element of choice into their lives, beyond identifying color food preferences for the tortoises. The element of choice is known to be important to animal welfare. PMID:24911428

Passos, Luiza F; Mello, Humberto Espirito Santo; Young, Robert John

2014-01-01

145

Preparation of biomembrane by immobilizing enriched ammonia-oxidizing bacteria (AOB) in polyvinyl alcohol (PVA) for biosensor  

Microsoft Academic Search

A biomembrane that was used to make a biosensor for detecting inhibitor of ammoia oxidation was prepared by entrapping enriched ammonia-oxidizing bacteria (AOB) in polyvinyl alcohol (PVA). AOB were enriched by fed batch cultivation with using return activated sludge from A 2 \\/O process as seed. Enrichment of AOB was confirmed by denaturing gradient gel electrophoresis (DGGE) analysis. The optimum

Rong Cui; Jinling Li; Ke Zhang; Jinglong Han

2011-01-01

146

Deuterium Enrichment of PAHs by VUV Irradiation of Interstellar Ices  

NASA Technical Reports Server (NTRS)

Laboratory results demonstrate that polycyclic aromatic hydrocarbons (PAHs) rapidly exchange their hydrogen atoms with those of nearby molecules when they are frozen into low-temperature ices and exposed to vacuum ultraviolet radiation. As a result, PAHs quickly become deuterium-enriched when VUV irradiated in D-containing ices. This mechanism has important consequences for several astrophysical issues owing to the ubiquitous nature of PAHs in the interstellar medium. For example, this process may explain the deuterium enrichments found in PAHs in meteorites and interplanetary dust particles. These results also provide general predictions about the molecular siting of the deuterium on aromatic materials in meteorites if this process produced a significant fraction of their D-enrichment.

Bernstein, Max P.; Sandford, Scott A.; Allamandola, Louis J.; Gillette, J. Seb; Zare, Richard N.; DeVincenzi, Donald (Technical Monitor)

1998-01-01

147

Method for Isotope Enrichment by Photoinduced Chemiionization.  

National Technical Information Service (NTIS)

Isotope enrichment, particularly exp 235 U enrichment, is achieved by irradiating an isotopically mixed vapor feed with radiant energy at a wavelength or wavelengths chosen to selectively excite the species containing a desired isotope to a predetermined ...

J. W. Dubrin

1976-01-01

148

Stable Isotope Inventory Requirements and Enrichment Capabilities.  

National Technical Information Service (NTIS)

The electromagnetic isotope enrichment program established in 1945 has since then continued to provide enriched stable, actinide, and selected radioactive isotopes. These unique materials used in research and medicine and for industrial applications are m...

W. A. Bell J. G. Tracy

1985-01-01

149

Enrichment of By-Product Materials from Steel Pickling Acid Regeneration Plants (TRP 9942).  

National Technical Information Service (NTIS)

A new process for manufacturing an enriched, iron-based product (Strontium Hexaferrite) in existing steel pickling acid regeneration facilities was evaluated. Process enhancements and equipment additions were made to an existing acid regeneration plant to...

L. Swan

2009-01-01

150

Inhomogeneous chemical enrichment of the universe  

NASA Astrophysics Data System (ADS)

Elemental and isotopic abundances are the fossils of galactic archaeology. The observed [X/Fe]-[Fe/H] relations in the Galactic bulge and disk and the mass-metallicity relation of galaxies are roughly reproduced with chemodynamical simulations of galaxies under the standard ?-CDM picture and standard stellar physics. The observed [Mn/Fe] will put a constraint on the progenitors of Type Ia Supernova, while [(Zn,Co)/Fe] will put a constraint on the fraction of hypernovae. The isotopic ratios such as 17,18O and 25,26Mg may require a refinement of modelling of supernova and asymptotic giant branch stars. The recent observation of the Carbon-rich Damped Lyman ? system can be reproduced only with faint core-collapse supernovae. This suggests that chemical enrichment by the first stars in the first galaxies is driven not by pair-instability supernovae but by core-collapse supernovae (~20-50Msolar). The observed F abundances can be reproduced with the neutrino processes of core-collapse supernovae. As in F, the observations of elemental abundances in small systems may requires further complications of chemical enrichment. In globular clusters the relative contribution from low-mass supernovae is smaller than in the field, while the contribution from massive supernovae is smaller in dwarf spheroidal galaxies than in the solar neighborhood.

Kobayashi, Chiaki

2012-11-01

151

Oxygen-enriched air production for MHD power plants  

NASA Astrophysics Data System (ADS)

An analysis of several of the cryogenic air separation process cycle variations and compression schemes designed to minimize net system power requirements for supplying pressurized, oxygen-enriched air to the combustor of a 2000 MWt (coal input) baseload MHD power plant is presented.

1980-05-01

152

Polychaetes as indicators of marine fish farm organic enrichment  

Microsoft Academic Search

Marine fish farms cause environmental disturbance of sediment due to uneaten food and fish faeces that accumulate on the sea bottom. These products give rise to organic enrichment followed by degradation processes; reduction of level of dissolved oxygen in the bottom water; generation of high levels of sulfides; changes of benthic assemblages and even azoic conditions. The soft bottom benthic

P. Tomassetti; S. Porrello

2005-01-01

153

Progress in alkaline peroxide dissolution of low-enriched uranium metal and silicide targets  

SciTech Connect

This paper reports recent progress on two alkaline peroxide dissolution processes: the dissolution of low-enriched uranium metal and silicide (U{sub 3}Si{sub 2}) targets. These processes are being developed to substitute low-enriched for high-enriched uranium in targets used for production of fission-product {sup 99}Mo. Issues that are addressed include (1) dissolution kinetics of silicide targets, (2) {sup 99}Mo lost during aluminum dissolution, (3) modeling of hydrogen peroxide consumption, (4) optimization of the uranium foil dissolution process, and (5) selection of uranium foil barrier materials. Future work associated with these two processes is also briefly discussed.

Chen, L.; Dong, D.; Buchholz, B.A.; Vandegrift, G.F. [Argonne National Lab., IL (United States). Chemical Technology Div.; Wu, D. [Univ. of Illinois, Urbana, IL (United States)

1996-12-31

154

Environmental enrichment for primates in laboratories  

NASA Astrophysics Data System (ADS)

Environmental enrichment is a critical component of Refinement, one of the 3Rs underlying humane experimentation on animals. In this paper I discuss why primates housed in laboratories, which often have constraints of space and study protocols, are a special case for enrichment. I outline a framework for categorising the different types of enrichment, using the marmoset as a case study, and summarise the methods used to determine what animals want/prefer. I briefly review the arguments that enrichment does not negatively affect experimental outcomes. Finally I focus on complexity and novelty, choice and control, the underlying features of enrichment that makes it successful, and how combined with a thorough understanding of natural history we can put effective enrichment into practice in laboratories. Throughout the paper I emphasise the need to evaluate enrichment to ensure it is having the desired effect.

Buchanan-Smith, H. M.

2010-06-01

155

Assay of low-enriched uranium using spontaneous fission neutrons  

SciTech Connect

Low-enriched uranium oxide in bulk containers can be assayed for safeguards purposes, using the neutrons from spontaneous fission of /sup 238/U as a signature, to complement enrichment and mass measurement. The penetrability of the fast fission neutrons allows the inner portion of bulk samples to register. The measurement may also be useful for measuring moisture content, of significance in process control. The apparatus used can be the same as for neutron correlation counting for Pu assay. The neutron multiplication observed in /sup 238/U is of intrinsic interest.

Zucker, M.S.; Fainberg, A.

1980-01-01

156

The paradox of enrichment in phytoplankton by induced competitive interactions.  

PubMed

The biodiversity loss of phytoplankton with eutrophication has been reported in many aquatic ecosystems, e.g., water pollution and red tides. This phenomenon seems similar, but different from the paradox of enrichment via trophic interactions, e.g., predator-prey systems. We here propose the paradox of enrichment by induced competitive interactions using multiple contact process (a lattice Lotka-Volterra competition model). Simulation results demonstrate how eutrophication invokes more competitions in a competitive ecosystem resulting in the loss of phytoplankton diversity in ecological time. The paradox is enhanced under local interactions, indicating that the limited dispersal of phytoplankton reduces interspecific competition greatly. Thus, the paradox of enrichment appears when eutrophication destroys an ecosystem either by elevated interspecific competition within a trophic level and/or destabilization by trophic interactions. Unless eutrophication due to human activities is ceased, the world's aquatic ecosystems will be at risk. PMID:24089056

Tubay, Jerrold M; Ito, Hiromu; Uehara, Takashi; Kakishima, Satoshi; Morita, Satoru; Togashi, Tatsuya; Tainaka, Kei-ichi; Niraula, Mohan P; Casareto, Beatriz E; Suzuki, Yoshimi; Yoshimura, Jin

2013-01-01

157

The paradox of enrichment in phytoplankton by induced competitive interactions  

PubMed Central

The biodiversity loss of phytoplankton with eutrophication has been reported in many aquatic ecosystems, e.g., water pollution and red tides. This phenomenon seems similar, but different from the paradox of enrichment via trophic interactions, e.g., predator-prey systems. We here propose the paradox of enrichment by induced competitive interactions using multiple contact process (a lattice Lotka-Volterra competition model). Simulation results demonstrate how eutrophication invokes more competitions in a competitive ecosystem resulting in the loss of phytoplankton diversity in ecological time. The paradox is enhanced under local interactions, indicating that the limited dispersal of phytoplankton reduces interspecific competition greatly. Thus, the paradox of enrichment appears when eutrophication destroys an ecosystem either by elevated interspecific competition within a trophic level and/or destabilization by trophic interactions. Unless eutrophication due to human activities is ceased, the world's aquatic ecosystems will be at risk.

Tubay, Jerrold M.; Ito, Hiromu; Uehara, Takashi; Kakishima, Satoshi; Morita, Satoru; Togashi, Tatsuya; Tainaka, Kei-ichi; Niraula, Mohan P.; Casareto, Beatriz E.; Suzuki, Yoshimi; Yoshimura, Jin

2013-01-01

158

Chemoselective enrichment for natural products discovery†  

PubMed Central

Natural products account for a significant proportion of modern day therapeutic agents. However, the discovery of novel compounds is hindered by the isolation process, which often relies upon extraction and chromatographic separation techniques. These methods, which are dependent upon the physicochemical properties of the compounds, have a limited ability to both purify and concentrate the minor components of a biological extract. We have devised an isolation strategy based upon an orthogonal chemical feature, namely, functional group composition. Development of a functional group-targeted method is expected to achieve exceptional resolution given the large number of distinct moieties present in natural product extracts. Here, we describe the generation of controllably reversible covalent enrichment tags for the chemoselective isolation of alcohol-containing natural products from complex mixtures.

Carlson, Erin E.

2014-01-01

159

Microfluidic platform for negative enrichment of circulating tumor cells.  

PubMed

Negative enrichment is the preferred approach for tumor cell isolation as it does not rely on biomarker expression. However, size-based negative enrichment methods suffer from well-known recovery/purity trade-off. Non-size based methods have a number of processing steps that lead to compounded cell loss due to extensive sample processing and handling which result in a low recovery efficiency. We present a method that performs negative enrichment in two steps from 2 ml of whole blood in a total assay processing time of 60 min. This negative enrichment method employs upstream immunomagnetic depletion to deplete CD45-positive WBCs followed by a microfabricated filter membrane to perform chemical-free RBC depletion and target cells isolation. Experiments of spiking two cell lines, MCF-7 and NCI-H1975, in the whole blood show an average of >90 % cell recovery over a range of spiked cell numbers. We also successfully recovered circulating tumor cells from 15 cancer patient samples. PMID:24668439

Sajay, Bhuvanendran Nair Gourikutty; Chang, Chia-Pin; Ahmad, Hamizah; Khuntontong, Puttachat; Wong, Chee Chung; Wang, Zhiping; Puiu, Poenar Daniel; Soo, Ross; Rahman, Abdur Rub Abdur

2014-08-01

160

Defining the needs for gas centrifuge enrichment plants advanced safeguards  

SciTech Connect

Current safeguards approaches used by the International Atomic Energy Agency (IAEA) at gas centrifuge enrichment plants (GCEPs) need enhancement in order to verify declared low-enriched (LEU) production, detect undeclared LEU production and detect highly enriched uranium (HEU) production with adequate detection probability using nondestructive assay (NDA) techniques. At present inspectors use attended systems, systems needing the presence of an inspector for operation, during inspections to verify the mass and {sup 235}U enrichment of declared UF{sub 6} containers used in the process of enrichment at GCEPs. In verifying declared LEU production, the inspectors also take samples for off-site destructive assay (DA) which provide accurate data, with 0.1% to 0.5% measurement uncertainty, on the enrichment of the UF{sub 6} feed, tails, and product. However, taking samples of UF{sub 6} for off-site analysis is a much more labor and resource intensive exercise for the operator and inspector. Furthermore, the operator must ship the samples off-site to the IAEA laboratory which delays the timeliness of results and interruptions to the continuity of knowledge (CofK) of the samples during their storage and transit. This paper contains an analysis of possible improvements in unattended and attended NDA systems such as process monitoring and possible on-site analysis of DA samples that could reduce the uncertainty of the inspector's measurements and provide more effective and efficient IAEA GCEPs safeguards. We also introduce examples advanced safeguards systems that could be assembled for unattended operation.

Boyer, Brian David [Los Alamos National Laboratory; Erpenbeck, Heather H [Los Alamos National Laboratory; Miller, Karen A [Los Alamos National Laboratory; Swinhoe, Martyn T [Los Alamos National Laboratory; Ianakiev, Kiril [Los Alamos National Laboratory; Marlowe, Johnna B [Los Alamos National Laboratory

2010-01-01

161

Surface enrichment of inorganic nutrients in the North Pacific Ocean  

NASA Astrophysics Data System (ADS)

Vertical profiles of the inorganic nutrients phosphate, silicate and nitrate show frequent surface enrichment (i.e. a sub-surface minimum) throughout the historical California Cooperative Oceanic Fisheries Investigations (CalCOFI) data set and in hydrographic sections across the North Pacific Ocean. Although present in the open ocean, it is especially pronounced in the offshore California Current and near the Hawaiian Islands. Its consistent occurrence over time, space, and methods argues that it is a real feature of the upper ocean ecosystem, rather than a result of some methodological problem. In the California Current, surface enrichment is spatially and temporally rare at nearshore stations. When nearshore enrichment does occur, minimum values are shallow (10-30 m). The subsurface minima become more frequent and deeper (eventually occurring at >100 m) the farther offshore one goes. A similar trend exists alongshore: the minima are deeper and more frequent towards the south. In all data, the enrichment is usually clearest and most frequent in silicate, weakest and least frequent in nitrate. Surface enrichment can contribute up to 100% of a specific inorganic nutrient available above the nutricline. The cause of surface enrichment is unknown: possible explanations include (1) nutrient scavenging and vertical transportation by rising particles or bubbles; (2) Langmuir circulations; (3) nutrient transport by vertically migrating organisms; (4) atmospheric inputs; (5) remineralization related to distributions of organisms with depth; or (6) photochemical processes. Because the three nutrients remineralize at different rates, this feature might be useful as a potential tracer of past or ongoing physical and biological processes in the mixed layer.

Haury, Loren R.; Fey, Connie L.; Shulenberger, Eric

1994-08-01

162

2,4-Dichlorophenoxyacetic Acid (2,4-D)- and 2,4,5-Trichlorophenoxyacetic Acid (2,4,5-T)-Degrading Bacterial Community in Soil-Water Suspension during the Enrichment Process.  

PubMed

Changes in the bacterial community in soil-water suspensions during the enrichment period of 2,4-D and 2,4,5-T degraders were examined using denaturing gradient gel electrophoresis (DGGE) analysis of the 16S rRNA gene. The nucleotide sequences of almost all major bands at the degradation of 2,4-D and 2,4,5-T corresponded to those of 2,4-D- and 2,4,5-T-degrading isolates, and successions of diverse 2,4-D- and 2,4,5-T-degrading bacterial communities were demonstrated in the DGGE profile. These results suggested that 2,4-D- and 2,4,5-T-degrading isolates were responsible for the degradation of 2,4-D and 2,4,5-T in soil-water suspensions; however, one major band of a non-degrader was found in some cases. Therefore, to elucidate the relationship between the structures and functions of bacterial communities, the importance of a combined approach using both culture-dependent and -independent methods was demonstrated. PMID:21558700

Huong, Nguyen L; Itoh, Kazuhito; Suyama, Kousuke

2008-01-01

163

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

Federal Register 2010, 2011, 2012, 2013

...enrichment facility--denoted as the Eagle Rock Enrichment Facility (EREF)--in Bonneville...Areva Enrichment Services, LLC (Eagle Rock Enrichment Facility), 74 FR 38,052...www.nrc.gov/materials/fuel-cycle-fac/arevanc.html. These and...

2011-06-10

164

Overview of reduced-enrichment fuels - development  

Microsoft Academic Search

The US Reduced Enrichment Research and Test Reactor (RERTR) Program was established in 1978 to provide the technical means to operate research and test reactors with low-enrichment uranium (LEU) fuels without significant penalty in experiment performance, operation costs, component modifications, or safety characteristics. A large increase in ²³⁸U is required to reduce the enrichment, and a 10 to 15% increase

Snelgrove

1987-01-01

165

Gas-phase UF/sub 6/ enrichment monitor for enrichment plant safeguards  

SciTech Connect

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

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

1980-03-01

166

Studies on Recovering Rutile from Titanium-Enriched High-Iron Smelter Slag.  

National Technical Information Service (NTIS)

Titanium-enriched smelter slag produced commercially by Quebec Iron and Titanium Corporation, Sorel, Quebec, was evaluated as feed material for a process developed by the Bureau of Mines and conducted at the Bureau's Albany Metallurgy Research Center. Gla...

D. H. Sumner J. Howe L. L. Oden

1973-01-01

167

PAGE: Parametric Analysis of Gene Set Enrichment  

Microsoft Academic Search

Background: Gene set enrichment analysis (GSEA) is a microarray data analysis method that uses predefined gene sets and ranks of genes to identify significant biological changes in microarray data sets. GSEA is especially useful when gene expression changes in a given microarray data set is minimal or moderate. Results: We developed a modified gene set enrichment analysis method based on

Seon-young Kim; David J. Volsky

2005-01-01

168

Enrichment Programs for Intellectually Gifted Pupils.  

ERIC Educational Resources Information Center

This report of the enrichment phase of California Project Talent is designed to provide guidelines for teachers in other schools. Part 1 contains five chapters on the planning phases of the enrichment program which was operated at the demonstration center of the Los Angeles Unified School District from 1963-1966. Included are rationale for…

Hill, Mary Broderick

169

Enrichment Monitor for 235U Fuel Tubes  

SciTech Connect

This report describes the performance of this prototype y-monitor of 235 Uranium enrichment. In this proposed method y-rates associated with 235U and 232U are correlated with enrichment. Instrumentation for appraising fuel tubes with this method has been assembled and tested.

Winn, W.G.

2001-08-22

170

Student science enrichment training program  

SciTech Connect

This is a report on the Student Science Enrichment Training Program, with special emphasis on chemical and computer science fields. The residential summer session was held at the campus of Claflin College, Orangeburg, SC, for six weeks during 1993 summer, to run concomitantly with the college`s summer school. Fifty participants selected for this program, included high school sophomores, juniors and seniors. The students came from rural South Carolina and adjoining states which, presently, have limited science and computer science facilities. The program focused on high ability minority students, with high potential for science engineering and mathematical careers. The major objective was to increase the pool of well qualified college entering minority students who would elect to go into science, engineering and mathematical careers. The Division of Natural Sciences and Mathematics and engineering at Claflin College received major benefits from this program as it helped them to expand the Departments of Chemistry, Engineering, Mathematics and Computer Science as a result of additional enrollment. It also established an expanded pool of well qualified minority science and mathematics graduates, which were recruited by the federal agencies and private corporations, visiting Claflin College Campus. Department of Energy`s relationship with Claflin College increased the public awareness of energy related job opportunities in the public and private sectors.

Sandhu, S.S.

1994-08-01

171

Enrichment Assay Methods Development for the Integrated Cylinder Verification System  

SciTech Connect

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampling of cylinders taken to be representative of the facility's entire product-cylinder inventory. Pacific Northwest National Laboratory (PNNL) is developing a concept to automate the verification of enrichment plant cylinders to enable 100 percent product-cylinder verification and potentially, mass-balance calculations on the facility as a whole (by also measuring feed and tails cylinders). The Integrated Cylinder Verification System (ICVS) could be located at key measurement points to positively identify each cylinder, measure its mass and enrichment, store the collected data in a secure database, and maintain continuity of knowledge on measured cylinders until IAEA inspector arrival. The three main objectives of this FY09 project are summarized here and described in more detail in the report: (1) Develop a preliminary design for a prototype NDA system, (2) Refine PNNL's MCNP models of the NDA system, and (3) Procure and test key pulse-processing components. Progress against these tasks to date, and next steps, are discussed.

Smith, Leon E.; Misner, Alex C.; Hatchell, Brian K.; Curtis, Michael M.

2009-10-22

172

ProbCD: enrichment analysis accounting for categorization uncertainty  

PubMed Central

Background As in many other areas of science, systems biology makes extensive use of statistical association and significance estimates in contingency tables, a type of categorical data analysis known in this field as enrichment (also over-representation or enhancement) analysis. In spite of efforts to create probabilistic annotations, especially in the Gene Ontology context, or to deal with uncertainty in high throughput-based datasets, current enrichment methods largely ignore this probabilistic information since they are mainly based on variants of the Fisher Exact Test. Results We developed an open-source R-based software to deal with probabilistic categorical data analysis, ProbCD, that does not require a static contingency table. The contingency table for the enrichment problem is built using the expectation of a Bernoulli Scheme stochastic process given the categorization probabilities. An on-line interface was created to allow usage by non-programmers and is available at: . Conclusion We present an analysis framework and software tools to address the issue of uncertainty in categorical data analysis. In particular, concerning the enrichment analysis, ProbCD can accommodate: (i) the stochastic nature of the high-throughput experimental techniques and (ii) probabilistic gene annotation.

Vencio, Ricardo ZN; Shmulevich, Ilya

2007-01-01

173

Thermal enrichment and speciation of copper in rice husk ashes  

Microsoft Academic Search

Copper(II) was considerably enriched in the residual ash via thermal treatment of copper-sorbed rice husk at 700–1100°C for 2h, and the copper speciation was quantitatively determined with X-ray absorption spectroscopy. After the thermal process, the resulting ash only represents by weight 18.7–26.4% of the pre-heated samples. Copper content in the ashes is >7% which is far above the required minimum

Yu-Ling Wei; Ming-Jan Hu; Yen-Hsun Peng

2010-01-01

174

Breadmaking performance of protein enriched, gluten-free breads  

Microsoft Academic Search

Soybean enriched, rice-based gluten-free breads were designed incorporating a structuring agent (hydroxypropylmethylcellulose,\\u000a HPMC) and a processing aid (transglutaminase, TG). At dough level the effect of increasing amounts of soybean protein isolate\\u000a (SPI), HPMC and water was studied in the Mixolab. Mixing and thermal characteristics showed the significant effect induced\\u000a by water, soybean protein isolate, HPMC and TG, allowing the selection

Cristina Marco; Cristina M. Rosell

2008-01-01

175

Parametric study on the enrichment of immunoglobulin from milk by foam fractionation.  

PubMed

Foam fractionation is a promising method for separation and concentration of biochemicals. It is simple, easily scalable, inexpensive, and environment friendly. Foam fractionation thus represents an alternative to the traditional methods used for immunoglobulin enrichment. However, little, if any, literature exists documenting the utilization of foam fractionation in the enrichment of immunoglobulins. Milk were utilized as an immunoglobulin source to serve as examples of a real system in this study. The investigation examined the effects of varying five different process parameters: the initial pH value, the initial concentration of immunoglobulin, the nitrogen flow rate, the column height, and the foaming time. Experimental results demonstrated that immunoglobulin could effectively be enriched from milk by foam fractionation. The maximum enrichment ratio with pretreatment (using pH 4.6 precipitation) was 6.30 along with a more than 92 % recovery for IgG and an enrichment ratio of 5.1 with 85 % recovery for IgM. PMID:23709288

Chen, Yen-Chih; Parlar, Harun

2013-08-01

176

21 CFR 136.115 - Enriched bread, rolls, and buns.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 2009-04-01 false Enriched bread, rolls, and buns. 136.115 Section...Bakery Products § 136.115 Enriched bread, rolls, and buns. (a) Each of the foods enriched bread, enriched rolls, and enriched...

2009-04-01

177

21 CFR 136.115 - Enriched bread, rolls, and buns.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Enriched bread, rolls, and buns. 136.115 Section...Bakery Products § 136.115 Enriched bread, rolls, and buns. (a) Each of the foods enriched bread, enriched rolls, and enriched...

2010-04-01

178

Status of stable isotope enrichment, products, and services at the Oak Ridge National Laboratory  

NASA Astrophysics Data System (ADS)

The Oak Ridge National Laboratory (ORNL) has been supplying enriched stable and radioactive isotopes to the research, medical, and industrial communities for over 50 y. Very significant changes have occurred in this effort over the past several years, and, while many of these changes have had a negative impact on the availability of enriched isotopes, more recent developments are actually improving the situation for both the users and the producers of enriched isotopes. ORNL is still a major producer and distributor of radioisotopes, but future isotope enrichment operations to be conducted at the Isotope Enrichment Facility (IEF) will be limited to stable isotopes. Among the positive changes in the enriched stable isotope area are a well-functioning, long-term contract program, which offers stability and pricing advantages; the resumption of calutron operations; the adoption of prorated conversion charges, which greatly improves the pricing of isotopes to small users; ISO 9002 registration of the IEF's quality management system; and a much more customer-oriented business philosophy. Efforts are also being made to restore and improve upon the extensive chemical and physical form processing capablities that once existed in the enriched stable isotope program. Innovative ideas are being pursued in both technical and administrative areas to encourage the beneficial use of enriched stable isotopes and the development of related technologies.

Scott Aaron, W.; Tracy, Joe G.; Collins, Emory D.

179

Biomechanical parameters of the BP-enriched bone cement.  

PubMed

Bisphosphonates (BPs) are well-known substances with very efficient antiresorptive properties. Their beneficial actions are useful not only in achieving better bone mineral density but also in improving bone microarchitecture, strength and, consequently, its quality. Surgical cement, being a polymer composite, is required to be highly biocompatible and biotolerant. The goal of the presented study was to assess whether the enrichment of cement with pamidronate has changed its biomechanical properties. We compared the biomechanical parameters of clean bone cement and BP-enriched bone cement, which were both used formerly in our rat models. Biomechanical properties of BP-enriched bone cement are defined by two basic terms: stress and strain, which are caused by the influence of external force. In the investigatory process of the bone's biomechanical parameters, the compressive test and the three-point flexural tests were used. During the three-point flexural investigation, the sample was supported at both ends and loaded in the middle, resulting in a flexure. After a specific range of flexure, the sample was fractured. In obtained results, there were no significant differences in the values of the stress determined at the point of maximal load and the energy stored in the samples for proportional stress-strain limit (elastic region). There were also no significant differences in the density of the samples. The study shows that the enrichment of bisphosphonates causes yielding of the bone cement material. In the presented data, we conclude that use of pamidronate implanted in bone cement did not have a detrimental effect on its biomechanical properties. Therefore, the obtained results encouraged us to perform further in vivo experiments which assess the biomechanical properties of bones implanted with BP-enriched bone cement. PMID:23670846

Matuszewski, Lukasz; Olchowik, Gra?yna; Mazurkiewicz, Tomasz; Kowalczyk, Bart?omiej; Zdrojewska, Agata; Matuszewska, Anna; Ciszewski, Andrzej; Gospodarek, Ma?gorzata; Morawik, Iwona

2014-05-01

180

MHD performance calculations with oxygen enrichment  

NASA Technical Reports Server (NTRS)

The impact of oxygen enrichment of the combustion air on the generator and overall plant performance was studied for the ECAS-scale MHD/steam plants. A channel optimization technique is described and the results of generator performance calculations using this technique are presented. Performance maps were generated to assess the impact of various generator parameters. Directly and separately preheated plant performance with varying O2 enrichment was calculated. The optimal level of enrichment was a function of plant type and preheat temperature. The sensitivity of overall plant performance to critical channel assumptions and oxygen plant performance characteristics was also examined.

Pian, C. C. P.; Staiger, P. J.; Seikel, G. R.

1979-01-01

181

Method for isotope enrichment by photoinduced chemiionization  

DOEpatents

Isotope enrichment, particularly .sup.235 U enrichment, is achieved by irradiating an isotopically mixed vapor feed with radiant energy at a wavelength or wavelengths chosen to selectively excite the species containing a desired isotope to a predetermined energy level. The vapor feed if simultaneously reacted with an atomic or molecular reactant species capable of preferentially transforming the excited species into an ionic product by a chemiionization reaction. The ionic product, enriched in the desired isotope, is electrostatically or electromagnetically extracted from the reaction system.

Dubrin, James W. (Walnut Creek, CA)

1985-01-01

182

An enrichment scheme for solidification problems  

NASA Astrophysics Data System (ADS)

A new enriched finite element formulation for solving isothermal phase change problems is presented. We propose a fixed mesh method, where the discontinuity in the temperature gradient is represented by enriching the finite element space through a function whose definition includes a gradient discontinuity. Generally, in these types of formulations, the enrichment location (the location of the solidification front) is determined through a level set auxiliary scheme. In this work, this position is determined implicitly by constraining the temperature at the phase change boundary to be equal to the melting temperature. Several numerical examples are presented to show the application of the method.

Cosimo, Alejandro; Fachinotti, Víctor; Cardona, Alberto

2013-07-01

183

Laser Isotope Enrichment for Medical and Industrial Applications  

SciTech Connect

Laser Isotope Enrichment for Medical and Industrial Applications by Jeff Eerkens (University of Missouri), Jay Kunze (Idaho State University), and Leonard Bond (Idaho National Laboratory) The principal isotope enrichment business in the world is the enrichment of uranium for commercial power reactor fuels. However, there are a number of other needs for separated isotopes. Some examples are: 1) Pure isotopic targets for irradiation to produce medical radioisotopes. 2) Pure isotopes for semiconductors. 3) Low neutron capture isotopes for various uses in nuclear reactors. 4) Isotopes for industrial tracer/identification applications. Examples of interest to medicine are targets to produce radio-isotopes such as S-33, Mo-98, Mo-100, W-186, Sn-112; while for MRI diagnostics, the non-radioactive Xe-129 isotope is wanted. For super-semiconductor applications some desired industrial isotopes are Si-28, Ga-69, Ge-74, Se-80, Te-128, etc. An example of a low cross section isotope for use in reactors is Zn-68 as a corrosion inhibitor material in nuclear reactor primary systems. Neutron activation of Ar isotopes is of interest in industrial tracer and diagnostic applications (e.g. oil-logging). . In the past few years there has been a sufficient supply of isotopes in common demand, because of huge Russian stockpiles produced with old electromagnetic and centrifuge separators previously used for uranium enrichment. Production of specialized isotopes in the USA has been largely accomplished using old ”calutrons” (electromagnetic separators) at Oak Ridge National Laboratory. These methods of separating isotopes are rather energy inefficient. Use of lasers for isotope separation has been considered for many decades. None of the proposed methods have attained sufficient proof of principal status to be economically attractive to pursue commercially. Some of the authors have succeeded in separating sulfur isotopes using a rather new and different method, known as condensation repression. In this scheme a gas, of the selected isotopes for enrichment, is irradiated with a laser at a particular wavelength that would excite only one of the isotopes. The entire gas is subject to low temperatures sufficient to cause condensation on a cold surface. Those molecules in the gas that the laser excited are not as likely to condense as are the unexcited molecules. Hence the gas drawn out of the system will be enriched in the isotope that was excited by the laser. We have evaluated the relative energy required in this process if applied on a commercial scale. We estimate the energy required for laser isotope enrichment is about 20% of that required in centrifuge separations, and 2% of that required by use of "calutrons".

Leonard Bond

2006-07-01

184

31 CFR 540.306 - Highly Enriched Uranium (HEU).  

Code of Federal Regulations, 2013 CFR

...ASSETS CONTROL REGULATIONS General Definitions § 540.306 Highly Enriched Uranium (HEU). The term highly enriched uranium or HEU means uranium enriched to twenty (20) percent or greater in the isotope...

2013-07-01

185

31 CFR 540.308 - Low Enriched Uranium (LEU).  

Code of Federal Regulations, 2013 CFR

...AGREEMENT ASSETS CONTROL REGULATIONS General Definitions § 540.308 Low Enriched Uranium (LEU). The term low enriched uranium or LEU means uranium enriched to less than twenty (20) percent in the isotope...

2013-07-01

186

21 CFR 137.165 - Enriched flour.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 false Enriched flour. 137.165 Section 137.165 ...FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.165...

2013-04-01

187

Enrichment of cations via bipolar electrode focusing.  

PubMed

We have previously demonstrated up to 5 × 10(5)-fold enrichment of anionic analytes in a microchannel using a technique called bipolar electrode focusing (BEF). Here, we demonstrate that BEF can also be used to enrich a cationic fluorescent tracer. The important point is that chemical modification of the microchannel walls enables reversal of the electroosmotic flow (EOF), enabling cations, instead of anions, to be enriched via an electric field gradient focusing mechanism. Reversal of the EOF has significant consequences on the formation and shape of the region of the buffer solution depleted of charge carriers (depletion zone). Electric field measurements and numerical simulations are used to elucidate the factors influencing the depletion zone. This information is used to understand and control the location and shape of the depletion zone, which in turn influences the stability and concentration of the enriched band. PMID:22891868

Sheridan, Eoin; Hlushkou, Dzmitry; Knust, Kyle N; Tallarek, Ulrich; Crooks, Richard M

2012-09-01

188

A Guide to Job Enrichment and Redesign.  

ERIC Educational Resources Information Center

Describes job design alternatives--job enrichment, the job characteristics model, Japanese style management, and quality-of-worklife approaches. Focuses on the problems that human resources professionals may encounter when attempting to implement these approaches. (Author/JOW)

Cunningham, J. Barton; Eberle, Ted

1990-01-01

189

Stable Isotope Enrichment Capabilities at ORNL  

SciTech Connect

The Oak Ridge National Laboratory (ORNL) and the US Department of Energy Nuclear Physics Program have built a high-resolution Electromagnetic Isotope Separator (EMIS) as a prototype for reestablishing a US based enrichment capability for stable isotopes. ORNL has over 60 years of experience providing enriched stable isotopes and related technical services to the international accelerator target community, as well as medical, research, industrial, national security, and other communities. ORNL is investigating the combined use of electromagnetic and gas centrifuge isotope separation technologies to provide research quantities (milligram to several kilograms) of enriched stable isotopes. In preparation for implementing a larger scale production facility, a 10 mA high-resolution EMIS prototype has been built and tested. Initial testing of the device has simultaneously collected greater than 98% enriched samples of all the molybdenum isotopes from natural abundance feedstock.

Egle, Brian [ORNL; Aaron, W Scott [ORNL; Hart, Kevin J [ORNL

2013-01-01

190

Uranium enrichment activities: the SILVA program.  

National Technical Information Service (NTIS)

Through its commitment to a nuclear electricity generation policy, France holds today a specific position in the uranium enrichment market thanks to the modern multinational EURODIF gaseous diffusion plant. France has, altogether, a long-term goal in deve...

J. Guyot J. Cazalet N. Camarcat J. Figuet

1994-01-01

191

Management's Ecstasy and Disparity Over Job Enrichment  

ERIC Educational Resources Information Center

A case study analyzing job enrichment schemes and manager expectations of increased productivity is presented. It was found that it was the managers' expectations of increased productivity, not the reorganization of work, that led to higher productivity. (EC)

King, Albert S.

1976-01-01

192

Measurement of uranium enrichment for gaseous uranium at low pressure  

SciTech Connect

X-ray fluoresence determines the amount of total uranium present in gaseous UF/sub 6/ inside cascade header pipes of a uranium centrifuge enrichment facility. A highly collimated source, highly collimated detector, and a very rigid, reproducible geometry are required. Two measurements of the 185.7-keV gamma ray from /sup 235/U using two collimators determine the amount of /sup 235/U present only in the gas phase. The ratio of the gas-only /sup 235/U signal to the total uranium gas-only signal is directly proportional to the enrichment of the process UF/sub 6/ gas. This measurement technique is independent of the deposit that forms on a surface in contact with UF/sub 6/. This measurement technique is independent of the pressure of the gaseous UF/sub 6/. This technique has the required sensitivity to determine whether the process gas is of uranium enrichment less than or equal to 20% or >20%. 6 refs., 4 figs., 4 tabs.

Close, D.A.; Pratt, J.C.; Atwater, H.F.; Malanify, J.J.; Nixon, K.V.; Speir, L.G.

1985-01-01

193

Amalgamation in CASL via Enriched Signatures  

Microsoft Academic Search

We construct a representation of the institution of the algebraic specification language Casl in an institution called enriched Casl. Enriched Casl satisfies the amalgamation property, which fails in the Casl institution, as well as its converse. Thus, the previously suggested institution-independent semantics of architectural specifications\\u000a is actually applicable to Casl. Moreover, a variety of results for institutions with amalgamation, such

Lutz Schröder; Till Mossakowski; Andrzej Tarlecki

2001-01-01

194

Dynamic fracture with meshfree enriched XFEM  

Microsoft Academic Search

The enrichment of the extended finite element method (XFEM) by meshfree approximations is studied. The XFEM allows for modeling\\u000a arbitrary discontinuities, but with low order elements the accuracy often needs improvement. Here, the meshfree approximation\\u000a is used as an enrichment in a cluster of nodes about the crack tip to improve accuracy. Several numerical examples show that\\u000a this leads to

Thomas Menouillard; Ted Belytschko

2010-01-01

195

Enriching text with images and colored light  

NASA Astrophysics Data System (ADS)

We present an unsupervised method to enrich textual applications with relevant images and colors. The images are collected by querying large image repositories and subsequently the colors are computed using image processing. A prototype system based on this method is presented where the method is applied to song lyrics. In combination with a lyrics synchronization algorithm the system produces a rich multimedia experience. In order to identify terms within the text that may be associated with images and colors, we select noun phrases using a part of speech tagger. Large image repositories are queried with these terms. Per term representative colors are extracted using the collected images. Hereto, we either use a histogram-based or a mean shift-based algorithm. The representative color extraction uses the non-uniform distribution of the colors found in the large repositories. The images that are ranked best by the search engine are displayed on a screen, while the extracted representative colors are rendered on controllable lighting devices in the living room. We evaluate our method by comparing the computed colors to standard color representations of a set of English color terms. A second evaluation focuses on the distance in color between a queried term in English and its translation in a foreign language. Based on results from three sets of terms, a measure of suitability of a term for color extraction based on KL Divergence is proposed. Finally, we compare the performance of the algorithm using either the automatically indexed repository of Google Images and the manually annotated Flickr.com. Based on the results of these experiments, we conclude that using the presented method we can compute the relevant color for a term using a large image repository and image processing.

Sekulovski, Dragan; Geleijnse, Gijs; Kater, Bram; Korst, Jan; Pauws, Steffen; Clout, Ramon

2008-01-01

196

Root growth and development in response to CO2 enrichment  

NASA Technical Reports Server (NTRS)

A non-destructive technique (minirhizotron observation tubes) was used to assess the effects of CO2 enrichment on root growth and development in experimental plots in a scrub oak-palmetto community at the Kennedy Space Center. Potential effects of CO2 enrichment on plants have a global significance in light of concerns over increasing CO2 concentrations in the Earth's atmosphere. The study at Kennedy Space Center focused on aboveground physiological responses (photosynthetic efficiency and water use efficiency), effects on process rates (litter decomposition and nutrient turnover), and belowground responses of the plants. Belowground dynamics are an exceptionally important component of total plant response but are frequently ignored due to methodological difficulties. Most methods used to examine root growth and development are destructive and, therefore, severely compromise results. Minirhizotrons allow nondestructive observation and quantification of the same soil volume and roots through time. Root length density and root phenology were evaluated for CO2 effects with this nondestructive technique.

Day, Frank P., Jr.

1994-01-01

197

Characterization of Protein Serotonylation via Bioorthogonal Labeling and Enrichment.  

PubMed

Protein serotonylation is a transglutaminase-mediated phenomenon whose biological mechanism of protein serotonylation is not yet fully understood, as the complete profiling of serotonylation targets in a proteome remains a critical challenge to date. Utilizing an alkyne-functionalized serotonin derivative bioorthogonally coupled to a cleavable linker, we developed a method to selectively enrich serotonylated proteins in a complex sample. With online nanoflow liquid chromatography and LTQ-Orbitrap Velos hybrid mass spectrometer detection, we identified 46 proteins with 50 serotonylation sites at their glutamine residues. Mass spectrometric analysis also generated direct residue-level evidence of various biological processes such as transglutaminase-chaperon interactions as well as actin assembly. An enrichment workflow utilizing click chemistry and on-bead digestion allowed us to achieve site-specific identification of protein serotonylation by mass spectrometry, and results obtained hereby also provided a great foundation in the elucidation of the true roles of protein serotonylation in biological systems. PMID:25055207

Lin, Jason Ching-Yao; Chou, Chi-Chi; Tu, Zhijay; Yeh, Lun-Fu; Wu, Shang-Chuen; Khoo, Kay-Hooi; Lin, Chun-Hung

2014-08-01

198

Surface enrichment of aluminosilicate minerals and coal combustion ash particles  

NASA Astrophysics Data System (ADS)

Auger electron spectroscopy has been used to provide evidence of surface segregation in illite, an aluminosilicate mineral representative of those which produce coal combustion ash particles. For the temperature range of 150-1100°C., the segregation of Fe, K, Ca and S has been observed, and the temperature dependence of the segregation levels of these elements has been determined. A comparison of these results with the reported data for surface enrichment of coal combustion ash particles indicates that the segregation levels of Fe, K, Ca and S in heated illite are comparable to the levels observed for the ash particles. Order-of-magnitude calculations indicate that appreciable segregation may occur on a time scale compatible with the residence time of ash particles in the combustor. These results are particularly significant because the surface enrichment of coal combustion ash has been generally attributed solely to adsorption/condensation processes.

Stinespring, C. D.; Stewart, G. W.

199

Reversal of cocaine addiction by environmental enrichment  

PubMed Central

Environmental conditions can dramatically influence the behavioral and neurochemical effects of drugs of abuse. For example, stress increases the reinforcing effects of drugs and plays an important role in determining the vulnerability to develop drug addiction. On the other hand, positive conditions, such as environmental enrichment, can reduce the reinforcing effects of psychostimulants and may provide protection against the development of drug addiction. However, whether environmental enrichment can be used to “treat” drug addiction has not been investigated. In this study, we first exposed mice to drugs and induced addiction-related behaviors and only afterward exposed them to enriched environments. We found that 30 days of environmental enrichment completely eliminates behavioral sensitization and conditioned place preference to cocaine. In addition, housing mice in enriched environments after the development of conditioned place preference prevents cocaine-induced reinstatement of conditioned place preference and reduces activation of the brain circuitry involved in cocaine-induced reinstatement. Altogether, these results demonstrate that environmental enrichment can eliminate already established addiction-related behaviors in mice and suggest that environmental stimulation may be a fundamental factor in facilitating abstinence and preventing relapse to cocaine addiction.

Solinas, Marcello; Chauvet, Claudia; Thiriet, Nathalie; El Rawas, Rana; Jaber, Mohamed

2008-01-01

200

Conversion and enrichment in the Soviet Union  

SciTech Connect

In the Soviet Union, just as in the West, the civilian nuclear industry emerged from research work undertaken for nuclear weapons development. At first, researchers tried various techniques for physical separation of uranium isotopes: electromagnetic and molecular-kinetic thermo-diffusion methods; gaseous diffusion; and centrifuge methods. All of those methods, which are based primarily on differences in the atomic mass of uranium isotopes, called for extensive research and the development of new, technically unprecedented equipment. Gradually gaseous diffusion and gas centrifuge technology became recognized as most feasible for industrial use, so research on other methods was terminated. Industrial-scale uranium enrichment in the Soviet Union began in 1949 using the gaseous diffusion method; by the early 1960s, centrifuge technology was in use on an industrial scale. All Soviet production of highly-enriched, weapons-grade uranium was halted in 1987. The Soviet Union now has four enrichment plants in operation (at classified locations), solely for civilian nuclear power needs. All four enrichment plants have centrifuge modules, and enrichment provided by gaseous diffusion accounts for less than 5% of their total output. Two of the four enrichment plants also incorporate facilities for conversion to uranium hexafluoride (UF{sub 6}).

NONE

1991-04-01

201

Toward a predictive theory for environmental enrichment.  

PubMed

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. PMID:19830747

Watters, Jason V

2009-11-01

202

Development of Enriched Borated Aluminum Alloy for Basket Material of Cask for Spent Nuclear Fuel  

Microsoft Academic Search

New enriched borated aluminum alloys manufactured by melting process are developed, which resulted in supplying structural basket materials for spent nuclear fuel packagings. In this process, the borated aluminum alloys were melted in a vacuum induction furnace at elevated temperature than that of ordinary aluminum melting processes. Boron dissolves into the matrix at the temperature of 1273 K or more,

Katsura Kajihara; Yasuhiro Aruga; Jun Shimojo; Hiroaki Taniuchi; Tsutomu Takeda; Masatosi Sasaki

2002-01-01

203

Gene expression profiles of the spleen, liver, and head kidney in turbot (Scophthalmus maximus) along the infection process with Aeromonas salmonicida using an immune-enriched oligo-microarray.  

PubMed

We evaluated the expression profiles of turbot in the spleen, liver, and head kidney across five temporal points of the Aeromonas salmonicida infection process using an 8?×?15 K Agilent oligo-microarray. The microarray included 2,176 different fivefold replicated gene probes designed from a turbot 3' sequenced EST database. We were able to identify 471 differentially expressed (DE) genes (17.3% of the whole microarray), 223 in the spleen, 246 in the liver, and 125 in the head kidney, in at least one of the five temporal points sampled for each organ. Most of these genes could be annotated (83.0%) and functionally categorized using Gene Ontology terms (69.1%) after the additional sequencing of DE genes from the 5' end. Many DE genes were related to innate and acquired immune functions in accordance to previous studies with this pathogen in other fish species. A high proportion of DE genes were organ specific (77.1%), but their associated GO functions were rather similar in the three organs. The most striking difference in functional distribution was observed between the up- and down-regulated gene groups. Up-regulated genes were mostly associated to key immune functions while down-regulated ones mainly involved metabolism- and transport-related genes. Genetic response appeared clustered in groups of genes with similar expression profiles along the temporal series. The spleen showed the most clustering while the liver and head kidney displayed a higher diversification. The information obtained will aid to understand the turbot immune response and will specifically be valuable to develop strategies of defense to A. salmonicida to achieve more resistant broodstocks for turbot industry. PMID:21503602

Millán, Adrián; Gómez-Tato, Antonio; Pardo, Belén G; Fernández, Carlos; Bouza, Carmen; Vera, Manuel; Alvarez-Dios, José Antonio; Cabaleiro, Santiago; Lamas, Jesús; Lemos, Manuel L; Martínez, Paulino

2011-12-01

204

Conversion and Blending Facility highly enriched uranium to low enriched uranium as uranyl nitrate hexahydrate. Revision 1  

SciTech Connect

This Conversion and Blending Facility (CBF) will have two missions: (1) convert HEU materials to pure HEU uranyl nitrate (UNH) and (2) blend pure HEU UNH with depleted and natural UNH to produce HEU UNH crystals. 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.

NONE

1995-07-05

205

Enrichment Determination of Uranium in Shielded Configurations  

SciTech Connect

The determination of the enrichment of uranium is required in many safeguards and security applications. Typical methods of determining the enrichment rely on detecting the 186 keV gamma ray emitted by {sup 235}U. In some applications, the uranium is surrounded by external shields, and removal of the shields is undesirable. In these situations, methods relying on the detection of the 186 keV gamma fail because the gamma ray is shielded easily. Oak Ridge National Laboratory (ORNL) has previously measured the enrichment of shielded uranium metal using active neutron interrogation. The method consists of measuring the time distribution of fast neutrons from induced fissions with large plastic scintillator detectors. To determine the enrichment, the measurements are compared to a calibration surface that is created from Monte Carlo simulations where the enrichment in the models is varied. In previous measurements, the geometry was always known. ORNL is extending this method to situations where the geometry and materials present are not known in advance. In the new method, the interrogating neutrons are both time and directionally tagged, and an array of small plastic scintillators measures the uncollided interrogating neutrons. Therefore, the attenuation through the item along many different paths is known. By applying image reconstruction techniques, an image of the item is created which shows the position-dependent attenuation. The image permits estimating the geometry and materials present, and these estimates are used as input for the Monte Carlo simulations. As before, simulations predict the time distribution of induced fission neutrons for different enrichments. Matching the measured time distribution to the closest prediction from the simulations provides an estimate of the enrichment. This presentation discusses the method and provides results from recent simulations that show the importance of knowing the geometry and materials from the imaging system.

Crye, Jason Michael [ORNL; Hall, Howard L [ORNL; McConchie, Seth M [ORNL; Mihalczo, John T [ORNL; Pena, Kirsten E [ORNL

2011-01-01

206

Bioactivity of herb-enriched beef patties.  

PubMed

Interest exists in the manufacture of meat products with added functional ingredients to enhance consumer health. Because experimental evidence suggests that many herbs and spices, particularly those of the Lamiaceae family such as Salvia officinalis L. (sage) and Origanum vulgare L. (oregano), possess a wide range of biological and pharmacological activities, they represent promising functional ingredients for incorporation into meat and meat products. The present study aimed to determine the bioactivity of cooked beef patties that were enriched with or without sage or oregano extracts (1,200 microg/g). Cooked beef patties were subjected to an in vitro digestion procedure, and the resulting micelles isolated from the digested meats were added to human intestinal Caco-2 cells. The antioxidant potential (ferric reducing antioxidant power [FRAP] value) of enriched beef patties was significantly higher than the FRAP value of non-enriched beef patties, both before and after in vitro digestion. Cell viability significantly increased following treatment with certain concentrations of the micelle fractions from digested sage- or oregano-enriched beef patties. Pretreatment with micelles derived from sage- or oregano-enriched beef patties did not significantly protect against cell injury or DNA damage induced by H(2)O(2). However, micelles derived from digested sage-enriched beef patties (10% vol/vol) significantly increased cellular reduced glutathione (GSH) content. In addition, micelles derived from both sage- and oregano-enriched beef patties (10% vol/vol) significantly protected against H(2)O(2)-induced GSH depletion. Thus, it appears that sage and oregano exhibit some bioactivity within a meat system. Our findings suggest that herbal extracts have potential as possible functional ingredients in meat products. PMID:19735192

Ryan, Eileen; Aherne, S Aisling; O'Grady, Michael N; McGovern, Laura; Kerry, Joseph P; O'Brien, Nora M

2009-08-01

207

Use of natural antioxidants from lyophilized water extracts of Borago officinalis in dry fermented sausages enriched in ?-3 PUFA  

Microsoft Academic Search

An evaluation of the capacity of a lyophilized water extract of borage leaves to delay the lipid oxidation process in dry fermented sausages enriched with ?-3 PUFAs has been performed. Lyophilized extract (340ppm) showed an antioxidant capacity equivalent to 200ppm of a butylhydroxyanisol (BHA) and butylhydroxytoluene (BHT) mixture. Two batches of dry fermented sausages enriched in ?-3 PUFA were developed.

Mikel García-Iñiguez de Ciriano; Cecilia García-Herreros; Eduardo Larequi; Idoia Valencia; Diana Ansorena; Iciar Astiasarán

2009-01-01

208

Test the effects of nutrient enrichment on organic carbon storage in western Pacific oligotrophic gyre  

NASA Astrophysics Data System (ADS)

In order to test the hypothesis that enrichment of nitrate and phosphate would decrease storage of organic carbon in the ocean (Jiao et al., 2011), we conducted a series of in-situ incubation experiments in the western Pacific Ocean. Five treatments were employed: organic carbon (glucose or algal exudation organic matter (EOM)) and macronutrient (nitrate and phosphate) were added alone or in combination with each other. The final concentration of organic carbon and macronutrient in treatments were 10 ?M/C/kg, 1.5 ?M/N/kg and 0.15 ?M/P/ respectively higher than those in controls. Total dissolved organic matter (TOC) concentration, bacterial abundance, and nitrate and phosphate concentration were monitored during the incubation processes. The results showed that the utilization of TOC and bacterial community growth rate were enhanced by inorganic nutrients enrichment treatments during the initial 48 hours incubation, regardless of glucose enrichment or not. Until the end of 14 days incubation, the percentage of remaining additional organic carbon was significant higher in the glucose enrichment treatments and EOM enrichment treatments (40.64% and 55.05%, respectively), compared to the combination of glucose and inorganic nutrients enrichment treatment (4.52%). These results suggest that inorganic nutrients enrichment condition may be adverse to short-term scale carbon storage, presumably due to the nutrient-stimulated bacterial metabolism and respiration, which is consistent to the hypothesis.

liu, J.; Jiao, N.; Tang, K.

2013-12-01

209

A unified enrichment scheme for fracture problems  

NASA Astrophysics Data System (ADS)

An enrichment scheme is presented in the framework of the extended finite element method (XFEM) that is independent of the material model. In the case of linear elastic fracture mechanics (LEFM), i.e. brittle fracture, stresses are singular at the crack-tip, whereas, in the case of cohesive fracture models, i.e. quasi-brittle cracks, stresses are finite at the crack-tip. Despite of the stress situation at the crack-tip, stresses are always finite in the region near the crack-tip and have a high gradient in the near-tip region. In order to cover almost all the stress gradients near the crack-tip, an optimal set of enrichment functions is found that can interpolate all the near-tip stress gradients starting from a large gradient that can no longer be captured by a standard FEM up to the situation where the gradient is almost infinite. An optimization study is conducted in order to find the optimal set of enrichment functions with respect to some error criterion. Test cases for static and quasi-static cracks are presented to show the usefulness and robustness of the proposed technique. In the case of brittle fracture, better results are achieved as compared to those obtained by the classical branch enrichments. The enrichment scheme is also used for the case of cohesive fracture and excellent agreement to available benchmarks is achieved.

Abbas, Safdar; Fries, Thomas-Peter

2010-06-01

210

Lower Metal Enrichment of Virialized Gas in Minihalos  

NASA Astrophysics Data System (ADS)

We differentiate between the metal enrichment of the gas in virialized minihalos and that of the intergalactic medium at high redshift, which is pertinent to cosmological reionization, with the initial expectation that gas in the high-density regions within formed dark matter halos may be more robust and thus resistant to mixing with the lower density intergalactic medium. Using detailed hydrodynamic simulations of gas clouds in minihalos subject to destructive processes associated with the encompassing intergalactic shocks carrying metal-enriched gas, we find, as an example, that, for realistic shocks with velocities of 10-100 km s-1, more than (90%, 65%) of the high-density gas with ?>=500?b inside a minihalo virialized at z=10 with a mass of (107, 106) Msolar, respectively, remains at a metallicity lower than 3% of that of the intergalactic medium by redshift z=6. It may be expected that the high-density gas in minihalos will become fuel for subsequent star formation when they are incorporated into larger halos, where efficient atomic cooling can induce gas condensation and hence star formation. Since minihalos virialize at high redshift, when the universe is not expected to have been significantly reionized, the implication is that gas in virialized minihalos may provide an abundant reservoir of primordial gas that could possibly allow the formation of Population III metal-free stars to extend to much lower redshifts than would have been otherwise expected on the basis of the enrichment of the intergalactic medium.

Cen, Renyue; Riquelme, Mario A.

2008-02-01

211

Uranium enrichment management review: summary of analysis  

SciTech Connect

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.

Not Available

1981-01-01

212

Fire extinguishment in oxygen enriched atmospheres  

NASA Technical Reports Server (NTRS)

Current state-of-the-art of fire suppression and extinguishment techniques in oxygen enriched atmosphere is reviewed. Four classes of extinguishment action are considered: cooling, separation of reactants, dilution or removal of fuel, and use of chemically reactive agents. Current practice seems to show preference for very fast acting water spray applications to all interior surfaces of earth-based chambers. In space, reliance has been placed on fire prevention methods through the removal of ignition sources and use of nonflammable materials. Recommendations are made for further work related to fire suppression and extinguishment in oxygen enriched atmospheres, and an extensive bibliography is appended.

Robertson, A. F.; Rappaport, M. W.

1973-01-01

213

Enriching the Design Process: Developing a Wearable Operator's Assistant  

Microsoft Academic Search

An interdisciplinary research team from Carnegie Mellon's Human-Computer Interaction Institute (HCII) collaborated with Inmedius Inc. (a CMU spin-off company) and colleagues in Shell Exploration and Production UK (EXPRO) to develop a Wearable Operator's Assistant (WOA) for workers on offshore oil rigs. The assistant is a handheld or wearable computer for technicians to perform daily operations and maintenance tasks on oil

Jack L. Moffett; Derek Wahila; Christopher Graefe; Jane Siegel; Jurry Swart

2000-01-01

214

Origin of middle rare earth element enrichment in acid mine drainage-impacted areas.  

PubMed

The commonly observed enrichment of middle rare earth elements (MREE) in water sampled in acid mine drainage (AMD)-impacted areas was found to be the result of preferential release from the widespread mineral pyrite (FeS2). Three different mining-impacted sites in Europe were sampled for water, and various pyrite samples were used in batch experiments with diluted sulphuric acid simulating AMD-impacted water with high sulphate concentration and high acidity. All water samples independent on their origin from groundwater, creek water or lake water as well as on the surrounding rock types showed MREE enrichment. Also the pyrite samples showed MREE enrichment in the respective acidic leachate but not always in their total contents indicating a process-controlled release. It is discussed that most probably complexation to sulphite (SO3 (2-)) or another intermediate S-species during pyrite oxidation is the reason for the MREE enrichment in the normalized REE patterns. PMID:24385183

Grawunder, Anja; Merten, Dirk; Büchel, Georg

2014-06-01

215

Effect of enriched municipal solid waste compost application on soil available macronutrients in the rice field  

Microsoft Academic Search

A study was conducted in the Department of Environmental Sciences, Tamil Nadu Agricultural University, Coimbatore, India, to transform the normal compost into bioactive compost, which has multiple benefits to the crop system. The key players in this transformation process were Azotobacter sp., Pseudomonas sp., Phosphobacteria sp. and the waste materials like poultry litter and spent wash. This enrichment process increases

Kavitha Ramadass; Subramanian Palaniyandi

2007-01-01

216

Enrichment of osteosarcoma stem cells by chemotherapy  

PubMed Central

Osteosarcoma is the most common primary malignant bone cancer in children and adolescents. Emerging evidence has suggested that the capability of a tumor to grow is driven by a small subset of cells within a tumor, termed cancer stem cells (CSCs). Although several methods have been explored to identify or enrich CSCs in osteosarcoma, these methods sometimes seem impractical, and chemotherapy enrichment for CSCs in osteosarcoma is rarely investigated. In the present study, we found that short exposure to chemotherapy could change the morphology of osteosarcoma cells and increase sarcosphere formation in vitro, as well as increase tumor formation in vivo. Furthermore, methotrexate (MTX)-resistant U2OS/MTX300 osteosarcoma cells were larger in size and grew much more tightly than parental U2OS cells. More importantly, U2OS/MTX300 cells possessed a higher potential to generate sarcospheres in serum-free conditions compared to parental U2OS cells. Also, U2OS/MTX300 cells exhibited the side population (SP) phenotype and expressed CSC surface markers CD117 and Stro-1. Notably, U2OS/MTX300 cells showed a substantially higher tumorigenicity in nude mice relative to U2OS cells. Therefore, we conclude that chemotherapy enrichment is a feasible and practical way to enrich osteosarcoma stem cells.

Tang, Qing-Lian; Liang, Yi; Xie, Xian-Biao; Yin, Jun-Qiang; Zou, Chang-Ye; Zhao, Zhi-Qiang; Shen, Jing-Nan; Wang, Jin

2011-01-01

217

Glycoprotein enrichment through lectin affinity techniques.  

PubMed

Posttranslational modifications (PTM) of proteins are among the key biological regulators of function, activity, localization, and interaction. The fact that no more than 30,000-50,000 proteins are encoded by the human genome underlines the importance of posttranslational modifications in modulating the activities and functions of proteins in health and disease. With approximately 50% of all proteins now considered to be glycosylated, its physiological importance in mammalian systems is imperative. Aberrant glycosylation has now been recognized as an attribute of many mammalian diseases, including hereditary disorders, immune deficiencies, neurodegenerative diseases, cardiovascular conditions, and cancer. As many potential disease biomarkers may be glycoproteins present in only minute quantities in tissue extracts and physiological fluids, glycoprotein isolation and enrichment may be critical in a search for such biomarkers. For decades, efforts have been focused on the development of glycoprotein enrichment from complex biological samples. Logically, the great majority of these enrichment methodologies rely on the use of immobilized lectins, which permit selective enrichment of the pools of glycoproteins for proteomic/glycomic studies. In this chapter, lectin affinity chromatography in different formats are described, including tubes; packed columns, and microfluidic channels. PMID:18369876

Mechref, Yehia; Madera, Milan; Novotny, Milos V

2008-01-01

218

Fair Value Enrichment Pricing: Is it Fair.  

National Technical Information Service (NTIS)

The Atomic Energy Act of 1954, as amended (Public Law 83-702), requires the Department of Energy to recover all costs for its enrichment activities over a reasonable period of time. The proposed legislation would allow the Department to recover its costs ...

1978-01-01

219

Enrichment for Nonhuman Primates: Capuchin Monkeys.  

National Technical Information Service (NTIS)

This book serves as an introduction to the basic behavior and environmental enrichment of a specific species of nonhuman primates that are more commonly used in education, research and entertainment. In many ways, this book is meant to be a how to manual;...

D. Fragaszy

2005-01-01

220

Enrichment for Nonhuman Primates: Squirrel Monkeys (Saimiri).  

National Technical Information Service (NTIS)

This book serves as an introduction to the basic behavior and environmental enrichment of a specific species of nonhuman primates that are more commonly used in education, research and entertainment. In many ways, this book is meant to be a how to manual;...

A. M. Schuler C. R. Abee

2005-01-01

221

Transportable calorimeter measurements of highly enriched uranium  

Microsoft Academic Search

A sensitive calorimeter has been combined with a small temperature-controlled water bath to compose a transportable system that is capable of measuring multikilogram quantities of highly enriched uranium (HEU). The sample chamber size, 5 in. in diameter by 10 in. high, is large enough to hold sufficient HEU metal or high-grade scrap to provide a measurable thermal signal. Calorimetric measurements

C. Rudy; D. S. Bracken; P. Staples; L. Carrillo

1997-01-01

222

Enriching a Child's Literacy Environment (ECLE).  

ERIC Educational Resources Information Center

The Enriching a Child's Literacy Environment (ECLE) program was designed to establish a model for teaching parents, teachers, and other care providers how to develop the oral language, thinking abilities and motor skills of young children (ages six months to three years). ECLE trainers instruct the parents or other care providers by first modeling…

Reid, Ethna R.

223

Robotic teaching for Malaysian gifted enrichment program  

Microsoft Academic Search

In Malaysia, interest of public toward robotic teachings has increasing astonishingly in the last few years. In most of technology learning environment in traditional classroom, the ways of learning could be dull and lack of activities that involved the children. In this paper, we present a curriculum development for a robotic class for Malaysian gifted enrichment program. During the program,

Rizauddin Ramli; Noriah Mohd Ishak

2011-01-01

224

ENRICHMENT OF HEAVY WATER BY THERMAL DIFFUSION  

Microsoft Academic Search

Equations of the best wire angle of inclination for the maximum separation, maximum output and minimum column height for enrichment of heavy water in a concentric-tube wired thermal diffusion column have been derived. Considerable improvements in performance were obtained by employing the wired column instead of using the open column (without wire). It was also found that the wire inclination

HO-MING YEH

1998-01-01

225

Query enrichment for web-query classification  

Microsoft Academic Search

Web-search queries are typically short and ambiguous. To classify these queries into certain target categories is a difficult but important problem. In this article, we present a new technique called query enrichment, which takes a short query and maps it to intermediate objects. Based on the collected intermediate objects, the query is then mapped to target categories. To build the

Dou Shen; Rong Pan; Jian-tao Sun; Jeffrey Junfeng Pan; Kangheng Wu; Jie Yin; Qiang Yang

2006-01-01

226

Weighted set enrichment of gene expression data  

PubMed Central

Background Sets of genes that are known to be associated with each other can be used to interpret microarray data. This gene set approach to microarray data analysis can illustrate patterns of gene expression which may be more informative than analyzing the expression of individual genes. Various statistical approaches exist for the analysis of gene sets. There are three main classes of these methods: over-representation analysis, functional class scoring, and pathway topology based methods. Methods We propose weighted hypergeometric and weighted chi-squared methods in order to assign a rank to the degree to which each gene participates in the enrichment. Each gene is assigned a weight determined by the absolute value of its log fold change, which is then raised to a certain power. The power value can be adjusted as needed. Datasets from the Gene Expression Omnibus are used to test the method. The significantly enriched pathways are validated through searching the literature in order to determine their relevance to the dataset. Results Although these methods detect fewer significantly enriched pathways, they can potentially produce more relevant results. Furthermore, we compare the results of different enrichment methods on a set of microarray studies all containing data from various rodent neuropathic pain models. Discussion Our method is able to produce more consistent results than other methods when evaluated on similar datasets. It can also potentially detect relevant pathways that are not identified by the standard methods. However, the lack of biological ground truth makes validating the method difficult.

2013-01-01

227

How to Enrich Geometry Using String Designs.  

ERIC Educational Resources Information Center

This book presents activities developed for grades 6-10 in creating string designs on polygons and polyhedra. They are designed for use as enrichment materials, each having step-by-step instructions and are arranged from easiest to most difficult, and marked accordingly. The pages are punched and perforated. Many activities are followed by related…

Pohl, Victoria

228

Origins of Enriched and Depleted Mantle Reservoirs  

Microsoft Academic Search

The relationships among plate tectonic circulation, continent formation and mantle heterogeneity have long been addressed through investigations of trace elements and isotopes in oceanic basalts. Various models, some involving recycled ocean crust, others involving mantle metasomatism by low degree peridotite melts, have been called upon to create the enriched signatures observed on ridges and ocean islands. The depleted reservoir, reflected

C. H. Langmuir; S. L. Goldstein; K. Donnelly; Y. J. Su

2005-01-01

229

Metacognitive Enrichment for Community College Students  

ERIC Educational Resources Information Center

Recent research was conducted to explore how introducing metacognitive enrichment into courses containing implicit or explicit critical thinking goals would affect the students' personal epistemological maturity. At the beginning of a fall semester at a moderate sized community college in the southeastern United States, 733 students were divided…

Wyre, Steven H.

2012-01-01

230

SUGGESTED URINARY TOLERANCE LEVELS FOR ENRICHED URANIUM  

Microsoft Academic Search

The animal experimentation basis for estimates of permissible levels of ; airborne, soluble, and insoluble natural uranium is briefly reviewed. It ; suggested that permissibie air and urinary levels for enriched uranium be set at ; values equivalent to those for natural uranium in terms of disintegrations per ; minute per unit volume. An attempt is made to calculate the

Hursh

1957-01-01

231

Implementing the Schoolwide Enrichment Model in Brazil  

ERIC Educational Resources Information Center

The Schoolwide Enrichment Model (SEM) has been one of the most widely used models in the education of the gifted in Brazil. It has inspired the political and pedagogical project of the Centers of Activities of High Abilities/Giftedness recently implemented in 27 Brazilian states by the Ministry of Education. In this article, our experience in…

de Souza Fleith, Denise; Soriano de Alencar, Eunice M. L.

2010-01-01

232

CUE (CULTURE, UNDERSTANDING, ENRICHMENT)--SCIENCE.  

ERIC Educational Resources Information Center

THIS PUBLICATION IS A TEACHING GUIDE TO PROVIDE GUIDANCE FOR INTEGRATING CAREFULLY SELECTED AUDIOVISUAL ITEMS INTO EXISTING NINTH-GRADE CURRICULUMS IN SCIENCE. IT IS ONE OF FIVE GUIDES PREPARED FOR USE IN PROJECT CUE, AN EXPERIMENTAL PROGRAM DESIGNED TO INCREASE CULTURAL UNDERSTANDING AND ENRICHMENT IN THE EDUCATIONAL PROGRAMS OF HIGH SCHOOLS. THE…

BROWN, ROBERT M.; AND OTHERS

233

Using Synchronous Technology to Enrich Student Learning  

ERIC Educational Resources Information Center

To explore the potential applications of synchronous technology to enrich student learning, faculty members from an American regional state university and a Chinese regional university collaborated to find appropriate ways to integrate synchronous technology (e.g., Adobe Connect) into an educational technology program in the American university…

Wang, Charles Xiaoxue; Jaeger, David; Liu, Jinxia; Guo, Xiaoning; Xie, Nan

2013-01-01

234

Projects To Enrich School Mathematics. Level 2.  

ERIC Educational Resources Information Center

This is a series of research projects that can be used for enrichment of the middle school mathematics curriculum. It is suggested that the topics are either not found in the standard curriculum or represent a more indepth study of standard topics. The areas considered are: microcomputer programs; divisibility; magic squares; pentominoes; the…

Sachs, Leroy, Ed.

235

Enriched domain detector: a program for detection of wide genomic enrichment domains robust against local variations  

PubMed Central

Nuclear lamins contact the genome at the nuclear periphery through large domains and are involved in chromatin organization. Among broad peak calling algorithms available to date, none are suited for mapping lamin–genome interactions genome wide. We disclose a novel algorithm, enriched domain detector (EDD), for analysis of broad enrichment domains from chromatin immunoprecipitation (ChIP)-seq data. EDD enables discovery of genomic domains interacting with broadly distributed proteins, such as A- and B-type lamins affinity isolated by ChIP. The advantages of EDD over existing broad peak callers are sensitivity to domain width rather than enrichment strength at a particular site, and robustness against local variations.

Lund, Eivind; Oldenburg, Anja R.; Collas, Philippe

2014-01-01

236

Vegetation and soil sampling for detection of enrichment facilities  

SciTech Connect

The concept of being able to detect clandestine nuclear operations rests on the fact that they invariably lose material characteristic of the process to the environment. This material can be collected and characterized using highly sensitive analytical techniques. The extent to which these signatures penetrate the environment depends on the type of process and the care taken at the facility to control losses. An enrichment facility that uses UF{sub 6}, a gas, will tend to lose more than a reactor because gases are harder to contain then solids. Any nuclear facility, like industrial processes everywhere, loses some characteristic material to the environment. The issues involved in acquiring environmental samples from around nuclear facilities are discussed, with the primary application being safeguards. Sampling plans, sample acquisition, analytical techniques, and data interpretation are described.

Smith, D.H.

1994-06-01

237

Intellectual enrichment is linked to cerebral efficiency in multiple sclerosis: functional magnetic resonance imaging evidence for cognitive reserve.  

PubMed

The cognitive reserve hypothesis helps to explain the incomplete relationship between brain disease and cognitive status in people with neurologic diseases, including Alzheimer's; disease and multiple sclerosis. Lifetime intellectual enrichment (estimated with education or vocabulary knowledge) lessens the negative impact of brain disease on cognition, such that people with greater enrichment are able to withstand more severe neuropathology before suffering cognitive impairment or dementia. The current research is the first to investigate directly the relationship between intellectual enrichment and an index of cerebral activity (the blood oxygen level dependent signal) in a neurologic sample. Multiple sclerosis patients completed a vocabulary-based estimate of lifetime intellectual enrichment. Disease severity was estimated with brain atrophy. Cognitive status was measured with the Symbol Digit Modalities Test. Cerebral activity (functional magnetic resonance imaging blood oxygen level dependent signal) and behavioural performance (accuracy, reaction time) were recorded during the visual N-Back working memory task (three levels of demand: 0-, 1-, 2-Back). All patients produced perfect/nearly perfect accuracy during lower demands (0- and 1-Back), and reaction time was unrelated to intellectual enrichment; however, voxelwise partial correlations controlling for brain atrophy revealed strong positive correlations between intellectual enrichment and cerebral activity within the brain's; default network (e.g. anterior and posterior cingulate corticies), indicating that patients with greater enrichment were able to maintain resting state activity during cognitive processing better. In turn, intellectual enrichment was negatively associated with prefrontal recruitment, suggesting that patients with lesser enrichment required more cerebral resources to perform the same cognitive task as patients with greater enrichment. This same pattern of enrichment-related cerebral activity was observed when cognitive demands increased (2-Back), and intellectual enrichment was negatively associated with reaction time. Principle components analysis revealed a single cognitive reserve network across tasks (greater default network, lesser prefrontal recruitment). Expression of this network almost fully mediated the positive relationship between intellectual enrichment and cognitive status (Symbol Digit Modalities Test). Also, expression of this network was positively associated with brain atrophy when controlling for cognitive status, indicating that patients with greater expression of this network can withstand more severe brain disease before exhibiting cognition similar to patients with lesser network expression. Of note, similar functional magnetic resonance imaging research with healthy adults has not found an association between intelligence and cerebral efficiency. The unique relationship between intellectual enrichment and cerebral efficiency in neurologic patients is consistent with the cognitive reserve hypothesis, which does not posit that enrichment leads to gains in neurocognitive functioning per se; rather, enrichment protects against neurocognitive decline secondarily to disease. PMID:20008455

Sumowski, James F; Wylie, Glenn R; Deluca, John; Chiaravalloti, Nancy

2010-02-01

238

Intellectual enrichment is linked to cerebral efficiency in multiple sclerosis: functional magnetic resonance imaging evidence for cognitive reserve  

PubMed Central

The cognitive reserve hypothesis helps to explain the incomplete relationship between brain disease and cognitive status in people with neurologic diseases, including Alzheimer's; disease and multiple sclerosis. Lifetime intellectual enrichment (estimated with education or vocabulary knowledge) lessens the negative impact of brain disease on cognition, such that people with greater enrichment are able to withstand more severe neuropathology before suffering cognitive impairment or dementia. The current research is the first to investigate directly the relationship between intellectual enrichment and an index of cerebral activity (the blood oxygen level dependent signal) in a neurologic sample. Multiple sclerosis patients completed a vocabulary-based estimate of lifetime intellectual enrichment. Disease severity was estimated with brain atrophy. Cognitive status was measured with the Symbol Digit Modalities Test. Cerebral activity (functional magnetic resonance imaging blood oxygen level dependent signal) and behavioural performance (accuracy, reaction time) were recorded during the visual N-Back working memory task (three levels of demand: 0-, 1-, 2-Back). All patients produced perfect/nearly perfect accuracy during lower demands (0- and 1-Back), and reaction time was unrelated to intellectual enrichment; however, voxelwise partial correlations controlling for brain atrophy revealed strong positive correlations between intellectual enrichment and cerebral activity within the brain's; default network (e.g. anterior and posterior cingulate corticies), indicating that patients with greater enrichment were able to maintain resting state activity during cognitive processing better. In turn, intellectual enrichment was negatively associated with prefrontal recruitment, suggesting that patients with lesser enrichment required more cerebral resources to perform the same cognitive task as patients with greater enrichment. This same pattern of enrichment-related cerebral activity was observed when cognitive demands increased (2-Back), and intellectual enrichment was negatively associated with reaction time. Principle components analysis revealed a single cognitive reserve network across tasks (greater default network, lesser prefrontal recruitment). Expression of this network almost fully mediated the positive relationship between intellectual enrichment and cognitive status (Symbol Digit Modalities Test). Also, expression of this network was positively associated with brain atrophy when controlling for cognitive status, indicating that patients with greater expression of this network can withstand more severe brain disease before exhibiting cognition similar to patients with lesser network expression. Of note, similar functional magnetic resonance imaging research with healthy adults has not found an association between intelligence and cerebral efficiency. The unique relationship between intellectual enrichment and cerebral efficiency in neurologic patients is consistent with the cognitive reserve hypothesis, which does not posit that enrichment leads to gains in neurocognitive functioning per se; rather, enrichment protects against neurocognitive decline secondarily to disease.

Wylie, Glenn R.; DeLuca, John; Chiaravalloti, Nancy

2010-01-01

239

Rapid quality control analysis of (13)C-enriched substrate synthesis by isotope ratio mass spectrometry.  

PubMed

There is a growing interest in the use of (13)C-enriched substrates to investigate metabolic processes in humans. The non-invasive nature of (13)C breath tests makes them attractive to clinicians, particularly because they can be safely used in children. The availability of suitable (13)C-enriched substrates can limit the application of this biotechnology. We have used isotope ratio mass spectrometry to assay the chemical purity and isotopic enrichment of substrates that were synthesised to study gut transit and colonic fermentation. Lactose ureide and lactose [(13)C]ureide were synthesised by acid-catalysed condensation of lactose and urea or (13)C urea, respectively. Glucose ureide and glucose [(13)C]ureide were synthesised by similar methods but required an additional purification step to remove urea of crystallisation. Substrates were analysed by standard analytical techniques and combustion isotope ratio mass spectrometry for carbon and nitrogen content and (13)C-enrichment. Monitoring the C/N ratio proved to be a sensitive assay of chemical purity. Analysis of the percentage composition of C and N (and hence O + H) suggested that lactose ureide crystallises as the dihydrate. It was synthesised with approximately 99% chemical purity and with the theoretical enrichment. Glucose ureide was synthesised with approximately 98% chemical purity but with lower than theoretical enrichment. PMID:11466784

Morrison, D J; Dodson, B; Preston, T; Weaver, L T

2001-01-01

240

Assessment of liquid disposal originated by uranium enrichment at Aramar Experimental Center São Paulo--Brazil.  

PubMed

This work presents a liquid disposal monitoring originated from uranium enrichment process at Aramar Experimental Center from 1990 to 1998. Assessment of uranium, fluorides, ammoniacal nitrogen, chemical oxygen demand, and pH measurements were made in water samples and compared with results achieved in other countries, as North America and India. The liquid disposal evaluation, generated by uranium enrichment process, showed low levels, considering most parameters established by Federal and State Legislation, aiming environmental pollution control. However, uranium levels were above the limits established by Conselho Nacional do Meio Ambiente, Environment Protection Agency and mainly by the World Health Organization. PMID:21814717

Gerenutti, Marli; Gonçalves, Marcos Moisés; Rissato, Sandra Regina; de Oliveira, José Martins; dos Santos Reigota, Marco Antonio; Galhiane, Mário Sergio

2012-07-01

241

Enriched Pyrite ?34S Signals in Modern Tropical Deltaic Muds  

NASA Astrophysics Data System (ADS)

The biogeochemical cycling of sulfur is one of the primary processes that regulate the Earth's surface redox conditions. In this study, we examine the abundance and sulfur isotopic composition (?34S) of pyrite through a series of cores collected from different water depths from the Gulf of Papua, Papua New Guinea. Physically undisturbed cores from deep water (depths up to 50 m) show relatively smooth ?34Spyr profiles with small scatter between adjacent samples within a core. In these cores, ?34Spyr gets gradually enriched from ~ -32‰ in the upper section to ~ -25‰ in the lower section. On the other hand, the ?34Spyr profiles in cores from shallow water depths (8 - 18 m) present larger scatter (up to 35‰) and unusually enriched ?34Spyr values (up to +36‰) are observed. These disparate results can be understood by combining a Rayleigh distillation model to explain elevated 34S values under closed-system conditions, together with the impact of episodic reworking of sediments, which enhances the stratigraphic variability of sulfide isotopic signals. Such different ?34Spyr patterns (both in their mean values and the degree of variability) between shallow water and deep water depositional environments, if preserved in the geologic record, could result in disparate interpretations. Understanding how modern depositional and diagenetic environments impact sulfur cycling processes gives us new insights when interpreting ancient sulfur isotope records.

Gao, J.; Fike, D. A.; Aller, R. C.

2013-12-01

242

Environmental monitoring for detection of uranium enrichment operations: Comparison of LEU and HEU facilities  

SciTech Connect

In 1994, the International Atomic Energy Agency (IAEA) initiated an ambitious program of worldwide field trials to evaluate the utility of environmental monitoring for safeguards. Part of this program involved two extensive United States field trials conducted at the large uranium enrichment facilities. The Paducah operation involves a large low-enriched uranium (LEU) gaseous diffusion plant while the Portsmouth facilities include a large gaseous diffusion plant that has produced both LEU and high-enriched uranium (HEU) as well as an LEU centrifuge facility. As a result of the Energy Policy Act of 1992, management of the uranium enrichment operations was assumed by the US Enrichment Corporation (USEC). The facilities are operated under contract by Martin Marietta Utility Services. Martin Marietta Energy Systems manages the environmental restoration and waste management programs at Portsmouth and Paducah for DOE. These field trials were conducted. Samples included swipes from inside and outside process buildings, vegetation and soil samples taken from locations up to 8 km from main sites, and hydrologic samples taken on the sites and at varying distances from the sites. Analytical results from bulk analysis were obtained using high abundance sensitivity thermal ionization mm spectrometers (TIMS). Uranium isotopics altered from the normal background percentages were found for all the sample types listed above, even on vegetation 5 km from one of the enrichment facilities. The results from these field trials demonstrate that dilution by natural background uranium does not remove from environmental samples the distinctive signatures that are characteristic of enrichment operations. Data from swipe samples taken within the enrichment facilities were particularly revealing. Particulate analysis of these swipes provided a detailed ``history`` of both facilities, including the assays of the end product and tails for both facilities.

Hembree, D.M. Jr.; Carter, J.A.; Ross, H.H.

1995-03-01

243

Mutant Enrichment with 3?-Modified Oligonucleotides  

PubMed Central

Many clinical situations necessitate highly sensitive and reliable molecular assays; however, the achievement of such assays remains a challenge due to the inherent limitations of molecular testing methods. Here, we describe a simple and inexpensive enrichment technique that we call mutant enrichment with 3?-modified oligonucleotides (MEMO). The method is based on the use of a 3?-modified oligonucleotide primer that blocks extension of the normal allele but enables extension of the mutated allele. The performance of the technique was evaluated with respect to its ability to detect common cancer mutations in the EGFR, KRAS, BRAF, TP53, JAK2, and NPM1 genes. We achieved sensitivities of 10?2 to 10?6 using downstream Sanger sequencing, depending on the concentrations and thermodynamics of the primers. MEMO may be applicable to the quantitative real-time PCR platform and other downstream assays. This technique may be practically applicable to various medical situations.

Lee, Seung-Tae; Kim, Ji-Youn; Kown, Min-Jung; Kim, Sun Wook; Chung, Jae Hoon; Ahn, Myung-Ju; Oh, Young Lyun; Kim, Jong-Won; Ki, Chang-Seok

2011-01-01

244

Inhibitory Action of Tetrathionate Enrichment Broth  

PubMed Central

Tetrathionate enrichment broth is a complex mixture of salts including iodides and other polythionates, but only thiosulfate (0.0736 m) and tetrathionate (0.0236 m) in combination were toxic for Escherichia coli. Individually, these two salts were not lethal. The lethal action of this thiosulfate-tetrathionate mixture affected only growing cells. A possible relationship between the lethality of the thiosulfate-tetrathionate mixture for a culture and its ability to reduce tetrathionate is suggested.

Palumbo, Samuel A.; Alford, John A.

1970-01-01

245

History-Enriched Spaces for Shared Encounters  

Microsoft Academic Search

\\u000a We discuss “history-enriched spaces” that use historical data to support shared encounters. We first examine our experiences\\u000a with DeaiExplorer, a social network display that uses RFID and a historical database to support social interactions at academic conferences.\\u000a This leads to our discussions on three complementary approaches to addressing the issues of supporting social encounters:\\u000a (1) embedding historical data in embodied

Shin’ichi Konomi; Kaoru Sezaki; Masaru Kitsuregawa

2010-01-01

246

Measurements of uranium holdup in an operating gaseous diffusion enrichment plant  

SciTech Connect

Holdup of nuclear material in process equipment is one of the major sources of uncertainty in materials balances, particularly for high-throughput facilities with large equipment and extensive piping, such as gaseous diffusion uranium-enrichment plants. Locating and measuring the holdup while the plant is operating is a challenging problem because of background from the process material and the neighboring equipment. This paper reports NDA measurements performed at the Goodyear Atomic Gaseous Diffusion Plant, Portsmouth, Ohio, on enrichment equipment at the higher enrichment and (>10% /sup 235/U isotopic abundance) of the cascade. Both neutron and gamma-ray measurements were made to locate anomalously large deposits in converters and compressors and, within the limitations of the techniques, to quantify the amount of the deposit.

Augustson, R.H.; Walton, R.B.; Harris, R.; Harbarger, W.; Hicks, J.; Timmons, G.; Shissler, D.; Tayloe, R.; Jones, S.; Fields, L.

1983-01-01

247

Turkey liver - a chromium enriched food source  

SciTech Connect

There are presently no known foods for humans that are particularly good sources of chromium. As a means of obtaining Cr enriched foods, turkeys were fed diets containing various levels of supplemental chromium. Four groups of 6-month old turkey hens were fed either the basal diet for laying hens or this diet supplemented with 25, 100 or 200 ..mu..g of chromium as chromium chloride per g of diet. Liver Cr concentration of the turkeys sacrificed after 1 week increased from 7 ng/g (wet wt) while consuming the basal diet to 15, 48 and 68 ng/g, respectively, while consuming the diets with supplemental chromium. Comparable values for the turkeys sacrificed after 5 weeks were 2, 43, 170 and 325 ng/g. Similar trends but higher chromium values were observed for kidney samples. The chromium contents of the dark and white meat and eggs were not altered significantly. Chromium concentrations of the pancreas, gizzard and heart increased marginally; final chromium concentrations were less than 23 ng/g even after 5 weeks on the highest level of supplemental chromium. Chromium content of spleen and lungs was approximately 2-fold higher than that of the pancreas, gizzard or heart. Therefore, turkey liver is a food source suitable for Cr enrichment while the eggs, dark and white meat and other edible parts do not appear to be enriched following chromium supplementation.

Polansky, M.M.; Bryden, N.A.; Richards, M.; Anderson, R.A.

1986-03-01

248

Core-collapse supernova enrichment in the core of the Virgo cluster  

NASA Astrophysics Data System (ADS)

Using a deep (574 ks) Chandra observation of M87, the dominant galaxy of the nearby Virgo cluster, we present the best measurements to date of the radial distribution of metals in the central intracluster medium (ICM). Our measurements, made in 36 independent annuli with ˜250 000 counts each, extend out to a radius r˜ 40 kpc and show that the abundance profiles of Fe, Si, S, Ar, Ca, Ne, Mg and Ni are all centrally peaked. Interestingly, the abundance profiles of Si and S - which are measured robustly and to high precision - are even more centrally peaked than Fe, while the Si/S ratio is relatively flat. These measurements challenge the standard picture of chemical enrichment in galaxy clusters, wherein Type Ia supernovae (SN Ia) from an evolved stellar population are thought to dominate the central enrichment. The observed abundance patterns are most likely due to one or more of the following processes: continuing enrichment by winds of a stellar population pre-enriched by core-collapse supernova (SNCC) products; intermittent formation of massive stars in the central cooling core; early enrichment of the low-entropy gas. We also discuss other processes that might have contributed to the observed radial profiles, such as a stellar initial mass function that changes with radius; changes in the pre-enrichment of SNCC progenitors; and a diversity in the elemental yields of SN Ia. Although systematic uncertainties prevent us from measuring the O abundance robustly, indications are that it is about two times lower than predicted by the enrichment models.

Million, E. T.; Werner, N.; Simionescu, A.; Allen, S. W.

2011-12-01

249

Availability of Enriched Stable Isotopes: Present Status and Future Prospects.  

National Technical Information Service (NTIS)

The Electromagnetic Isotope Enrichment Facility (EMIEF) is currently used to produce 225 enriched stable isotopes of 50 elements. Among these are included most of the known elements with stable isotopes except for the noble gases, certain light elements, ...

R. W. Hoff

1986-01-01

250

Enrichment Assay Methods Development for the Integrated Cylinder Verification System.  

National Technical Information Service (NTIS)

International Atomic Energy Agency (IAEA) inspectors currently perform periodic inspections at uranium enrichment plants to verify UF6 cylinder enrichment declarations. Measurements are typically performed with handheld high-resolution sensors on a sampli...

A. C. Misner B. K. Hatchell L. E. Smith M. M. Curtis

2009-01-01

251

Nutrient enrichment of the subarctic Pacific Ocean pycnocline  

NASA Astrophysics Data System (ADS)

At the end of the global thermohaline circulation, the subarctic Pacific is the richest nutrient repository in the world oceans. Trends towards lower oxygen and higher nutrients in waters below the surface layer (the pycnocline) have been observed in recent decades. We assess these trends using data from four programs and suggest the enrichment of pycnocline nitrate (200 Gmol y-1) is essential in keeping supply to the surface ocean constant, despite increasing upper ocean stratification. A nitrate budget helps identify possible vertical processes that could account for nutrient redistribution. We hypothesize that warming and oxygen loss in the deeper pycnocline, arising from ice loss in the Okhotsk Sea, have initiated a largely vertical redistribution of nutrients due to compression of vertical migrator habitat and/or changes in dissolution of sinking particulates. Coupled climate-ecosystem models will need to incorporate these processes to more fully understand projected changes in the subarctic Pacific.

Whitney, Frank A.; Bograd, Steven J.; Ono, Tsuneo

2013-05-01

252

Microbial response to a mesoscale iron enrichment in the NE Subarctic Pacific: Bacterial community composition  

NASA Astrophysics Data System (ADS)

Changes in microbial community composition were determined during the subarctic ecosystem response to iron enrichment study (SERIES), a mesoscale Fe enrichment conducted in a high-nutrient low-chlorophyll (HNLC) region of the Northeast Subarctic Pacific, in July 2002. Phylogenetic composition using fluorescence in situ hybridization (FISH), relative DNA content using flow cytometry (FCM), and cellular morphometrics (shape and volume) of heterotrophic bacteria were used to characterize community composition from samples collected within and below the mixed layer, inside and outside the Fe-patch. The proportion of total cells detected as members of the Cytophaga-Flavobacterium cluster increased in a log-linear manner from 16 (±1.0)% to 47 (±1.9)% in samples within the mixed layer, inside the Fe-enriched patch, while outside the patch, the proportion remained ?21 (±2.2)%. Temporal changes in the proportion of cells in the mixed layer with high DNA content (% HDNA) were significantly different inside and outside the Fe-enriched patch, where inside the patch % HDNA increased 2-fold after a week, reaching 93% towards the end of the observation period. Coupling in situ observations with the results of manipulation experiments allowed us to determine the relative contributions of bottom-up (nutrient limitation) and top-down (grazing) processes on heterotrophic bacterial abundance and community composition. Shifts in heterotrophic bacterial community composition inside the Fe-enriched patch were mainly controlled by top-down processes and moderately controlled by bottom-up controls (organic substrate limitation).

Agawin, Nona S. R.; Hale, Michelle S.; Rivkin, Richard B.; Matthews, Paul; Li, William K. W.

2006-10-01

253

Analysis of the effectiveness of gas centrifuge enrichment plants advanced safeguards  

SciTech Connect

Current safeguards approaches used by the International Atomic Energy Agency (IAEA) at gas centrifuge enrichment plants (GCEPs) need enhancement in order to verify declared low-enriched uranium (LEU) production, detect undeclared LEU production and detect highly enriched uranium (HEU) production with adequate detection probability using non destructive assay (NDA) techniques. At present inspectors use attended systems, systems needing the presence of an inspector for operation, during inspections to verify the mass and 235U enrichment of declared UF6 containers used in the process of enrichment at GCEPs. This paper contains an analysis of possible improvements in unattended and attended NDA systems including process monitoring and possible on-site destructive assay (DA) of samples that could reduce the uncertainty of the inspector's measurements. These improvements could reduce the difference between the operator's and inspector's measurements providing more effective and efficient IAEA GCEPs safeguards. We also explore how a few advanced safeguards systems could be assembled for unattended operation. The analysis will focus on how unannounced inspections (UIs), and the concept of information-driven inspections (IDS) can affect probability of detection of the diversion of nuclear materials when coupled to new GCEPs safeguards regimes augmented with unattended systems.

Boyer, Brian David [Los Alamos National Laboratory; Erpenbeck, Heather H [Los Alamos National Laboratory; Miller, Karen A [Los Alamos National Laboratory; Swinjoe, Martyn T [Los Alamos National Laboratory; Ianakiev, Kiril D [Los Alamos National Laboratory; Marlow, Johnna B [Los Alamos National Laboratory

2010-01-01

254

Enrichment Factors of Perfluoroalkyl Anionic Surfactants at the Air/water Interface  

NASA Astrophysics Data System (ADS)

The refractory, water-bound perfluoro-n-alkyl carboxylate (n-PFC-) and sulfonate (n- PFS-) surfactants reach remote locations hydrologically unconnected to their sources via hitherto unknown processes. Here we quantify the enrichment of these anions in microdroplets produced by aerosolization of 1 M aqueous surfactant solutions at pH 7 using sonic spray ionization mass spectrometry. Relative enrichment factors fsteeply increase from n= 1 to 3, level off at f(n-PFS-) ~ 2.3 f(n-PFC-) ~ 190 f(Br-) (n â?¥ 8), and display even-odd effects. The preferential enrichment of n-PFS- over n-PFC- reflects a larger headgroup. The hyperbolic, rather than the predicted linear ln fvs. ndependence suggests the onset of conformational restrictions to interfacial enrichment above n ~ 3. Marine aerosols produced from contaminated ocean surface waters are thus expected to be highly enriched in PFC-s/PFS-s. The monotonic accumulation of 8-PFS- and PFC-s in East and, less pronouncedly, in West Greenland biomarkers is therefore consistent with the deposition of marine aerosol drawn from contaminated North American Current waters and transported westward by predominant easterlies. The analogous trend for PFC-s in Canadian Arctic biota vis-a-vis the rapid decline of 8-PFS- after 2000 suggest that the fresher Labrador Sea does not sustain a similar process over this region.

Hoffmann, M. R.; Colussi, A. J.; Cheng, J.

2009-04-01

255

Public perceptions of behavioral enrichment: Assumptions gone awry  

Microsoft Academic Search

4 Brookfield Zoo, Brookfield, Illinois More and more, zoos are integrating behavioral enrichment programs into their management routines. Given the newness of such programs on an official level, however, there are an increasing number of enrichment decisions based on as- sumption. Enrichment is typically not provided on exhibit, especially for exhib- its considered to be more naturalistic, because it is

M. E. McPhee; J. S. Foster; M. Sevenich; C. D. Saunders

1998-01-01

256

Defining the needs for gas centrifuge enrichment plants advanced safeguards  

Microsoft Academic Search

Current safeguards approaches used by the International Atomic Energy Agency (IAEA) at gas centrifuge enrichment plants (GCEPs) need enhancement in order to verify declared low-enriched (LEU) production, detect undeclared LEU production and detect highly enriched uranium (HEU) production with adequate detection probability using nondestructive assay (NDA) techniques. At present inspectors use attended systems, systems needing the presence of an inspector

Brian David Boyer; Heather H Erpenbeck; Karen A Miller; Martyn T Swinhoe; Kiril Ianakiev; Johnna B Marlowe

2010-01-01

257

The Effect of Selenium Enrichment on Baker s Yeast Proteome  

PubMed Central

The use of regular yeast (RY) and selenium-enriched yeast (SEY) as dietary supplement is of interest because the Nutritional Prevention of Cancer (NPC) trial revealed that SEY but not RY decreased the incidence of prostate cancer (PC). Using two-dimensional difference in gel electrophoresis (2D-DIGE) – tandem mass spectrometry (MS/MS) approach, we performed proteomic analysis of RY and SEY to identify proteins that are differentially expressed as a result of selenium enrichment. 2D-DIGE revealed 96 candidate protein spots that were differentially expressed (p?0.05) between SEY and RY. The 96 spots were selected, sequenced by LC/MS/MS and 37 proteins were unequivocally identified. The 37 identified proteins were verified with ProteinProphet software and mapped to existing Gene Ontology categories. Furthermore, the expression profile of 5 of the proteins with validated or putative roles in the carcinogenesis process, and for which antibodies against human forms of the proteins are available commercially were verified by western analysis. This study provides evidence for the first time that SEY contains higher levels of Pyruvate Kinase, HSP70, and Elongation factor 2 and lower levels of Eukaryotic Translation Initiation Factor 5A-2 and Triosephosphate Isomerase than those found in RY.

El-Bayoumy, Karam; Das, Arunangshu; Russell, Stephen; Wolfe, Steven; Jordan, Rick; Renganathan, Kutralanathan; Loughran, Thomas P.; Somiari, Richard

2011-01-01

258

Paradox of enrichment: A fractional differential approach with memory  

NASA Astrophysics Data System (ADS)

The paradox of enrichment (PoE) proposed by Rosenzweig [M. Rosenzweig, The paradox of enrichment, Science 171 (1971) 385-387] is still a fundamental problem in ecology. Most of the solutions have been proposed at an individual species level of organization and solutions at community level are lacking. Knowledge of how learning and memory modify behavioral responses to species is a key factor in making a crucial link between species and community levels. PoE resolution via these two organizational levels can be interpreted as a microscopic- and macroscopic-level solution. Fractional derivatives provide an excellent tool for describing this memory and the hereditary properties of various materials and processes. The derivatives can be physically interpreted via two time scales that are considered simultaneously: the ideal, equably flowing homogeneous local time, and the cosmic (inhomogeneous) non-local time. Several mechanisms and theories have been proposed to resolve the PoE problem, but a universally accepted theory is still lacking because most studies have focused on local effects and ignored non-local effects, which capture memory. Here we formulate the fractional counterpart of the Rosenzweig model and analyze the stability behavior of a system. We conclude that there is a threshold for the memory effect parameter beyond which the Rosenzweig model is stable and may be used as a potential agent to resolve PoE from a new perspective via fractional differential equations.

Rana, Sourav; Bhattacharya, Sabyasachi; Pal, Joydeep; N'Guérékata, Gaston M.; Chattopadhyay, Joydev

2013-09-01

259

Preparation and characterization of carbon-enriched coal fly ash.  

PubMed

Carbon-enriched fractions have been obtained from two coal fly ash (FA) samples. The FA came from two pulverized-coal fired power stations (Lada and Escucha, Spain) and were collected from baghouse filters. Sieving was used to obtain carbon-enriched fractions, which were further subjected to two beneficiation processes: acid demineralization using HCl and HF, and oil agglomeration using soya oil-water. Yield in weight after sieving, unburned carbon content, and several physicochemical characteristics of the obtained fractions were used to compare the performance of the beneficiation methods. Low carbon concentration was obtained by sieving, particularly in the case of Escucha FA. However, after acid demineralization or oil agglomeration, fractions containing unburned carbon in a range of 63% to 68% were obtained. These fractions showed differences in mineral phase composition and distribution depending on the FA and on the beneficiation method used. The textural properties of the obtained fractions varied as a function of their carbon content and the beneficiation method used. However, no significant differences in morphology of the carbonaceous particles were found. PMID:17826888

Rubio, B; Izquierdo, M T; Mayoral, M C; Bona, M T; Martínez-Tarazona, R M

2008-09-01

260

Synthesis of Neutron Enriched Heavy and Superheavy Nuclei  

NASA Astrophysics Data System (ADS)

Applicability of different nuclear reactions (fusion of stable and radioactive nuclei, multi-nucleon transfers and neutron capture) for the production of new neutron enriched heavy nuclei is discussed in the paper. For the first time, a narrow pathway is found to the middle of the island of stability owing to possible ?+-decay of SH isotopes which can be formed in ordinary fusion reactions of stable nuclei. Neutron capture reactions can be also used for the production of the long-living neutron rich SH nuclei. Strong neutron fluxes might be provided by pulsed nuclear reactors and by multiple nuclear explosions in laboratory conditions and by supernova explosions in nature. Low-energy multinucleon transfer reactions with actinide beams and targets are of special interest for synthesis of new neutron enriched transfermium nuclei and not-yet-known nuclei around the closed neutron shell N = 126 having largest impact on astrophysical r process. The estimated cross sections for the production of these nuclei look very promising to plan such experiments at available accelerators. Several new test experiments of such kind are proposed to perform including those in which a role of the shell effects in low-energy reaction dynamics could be clarify much better.

Zagrebaev, V. I.; Karpov, A. V.; Greiner, Walter

2014-09-01

261

Carbon isotopic enrichment in Titan's Tholins: implications for Titan's aerosols  

NASA Astrophysics Data System (ADS)

Since the discovery of the main composition of Titan s atmosphere many laboratory experiments have been carried out to mimic its chemical evolution and in particular the formation of the haze particles of this atmosphere Indeed the solid products obtained during these simulation experiments -- often named Titan s tholins -- are supposed to be analogues of Titan s aerosols and many studies have already been achieved on these tholins We have studied the possible isotopic fractionation of carbon during the processes involved in the formation of Titan s tholins using tholins obtained from different simulation experiments We will present the first results obtained on the isotopic ratios of 13 C 12 C measured on the analogues of Titan s aerosols synthesized in laboratory Measurement of delta 13 C leaded both on laboratory aerosols and on the initial gas mixture N 2 CH 4 98 2 used in the simulations doesn t show any evident deficit or enrichment of 13 C in comparison with 12 C in the aerosols synthesised compared to the initial gas mixture Preliminary retrieving of the data of the ACP instrument on the Huygens probe suggests that Titan s aerosols may present also no enrichment This allows us to go further in the analyses of the ACP data in comparison with the first conclusions newly published in Nature Isra e l et al Nature 2005

Nguyen, N.; Raulin, R.; Coll, C.; Derenne, D.; Szopa, S.; Israël, I.; Cernogora, C.; Bernard, B.

262

Fissile Flow and Enrichment Monitor for GCEP Advanced Safeguards Application  

SciTech Connect

This paper presents experimental data that demonstrate a concept for a {sup 235}U flow and enrichment monitor (FEMO) based on passive measurements of process equipment in gaseous centrifuge enrichment plants (GCEPs). The primary goal of the FEMO is to prevent, without using pipe penetrations or active interrogation with external sources, the production and diversion of undeclared nuclear material. This FEMO concept utilizes: (1) calibrated measurements of {sup 235}U density in cascade headers, and (2) measurements of pump inlet pressure and volumetric flow rate, which are correlated to the electrical power consumed by the GCEP pumps that transport UF{sub 6} from the cascade to the condensation cylinders. The {sup 235}U density is measured by counting 186 keV emissions using a NaI gamma detector located upstream of the pump. The pump inlet pressure and volumetric flow rate are determined using a correlation that is a function of the measured pump operational parameters (e.g., electric power consumption and rotational frequency) and the pumping configuration. The concept has been demonstrated in a low-pressure flow loop at Oak Ridge National Laboratory.

March-Leuba, Jose A [ORNL; Uckan, Taner [ORNL

2010-01-01

263

Kinetics of Coal Char Combustion in Oxygen-Enriched Environment  

NASA Astrophysics Data System (ADS)

The influence of oxygen-enriched gaseous atmosphere on coal char combustion was studied. Two different coals, i.e. lignite and bituminous coal, were used as a basic fuel and the reacting gases of oxygen & CO2 were used to simulate flue gas recirculation. Moreover, a broad range of in-furnace conditions, i.e. five temperatures of 873, 973, 1073, 1173, 1273K and five oxygen concentrations of 20, 40, 60, 80, 100%vol., was investigated. Thermogravimetric method of measurement was employed to obtain the processing data on fuel conversion rate under foregoing investigated conditions. For further calculations, simplified Shrinking-Core Model was introduced. Finally, fundamental kinetic parameters, i.e. pre-exponential factor, activation energy and reaction order, were established and then on the basis of their values reaction-controlling regime for coal char combustion in oxygen-enriched environment was predicted. The investigations, financially supported by Polish Government, are a part of Framework Project "Supercritical Coal-fired Power Units".

Czakiert, T.; Nowak, W.

264

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

SciTech Connect

The US and UK have been separately working on the development of a NDA instrument to determine the enrichment of gaseous UF/sub 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 ..gamma..-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.

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

1985-01-01

265

Enriched biodiversity data as a resource and service  

PubMed Central

Abstract Background: Recent years have seen a surge in projects that produce large volumes of structured, machine-readable biodiversity data. To make these data amenable to processing by generic, open source “data enrichment” workflows, they are increasingly being represented in a variety of standards-compliant interchange formats. Here, we report on an initiative in which software developers and taxonomists came together to address the challenges and highlight the opportunities in the enrichment of such biodiversity data by engaging in intensive, collaborative software development: The Biodiversity Data Enrichment Hackathon. Results: The hackathon brought together 37 participants (including developers and taxonomists, i.e. scientific professionals that gather, identify, name and classify species) from 10 countries: Belgium, Bulgaria, Canada, Finland, Germany, Italy, the Netherlands, New Zealand, the UK, and the US. The participants brought expertise in processing structured data, text mining, development of ontologies, digital identification keys, geographic information systems, niche modeling, natural language processing, provenance annotation, semantic integration, taxonomic name resolution, web service interfaces, workflow tools and visualisation. Most use cases and exemplar data were provided by taxonomists. One goal of the meeting was to facilitate re-use and enhancement of biodiversity knowledge by a broad range of stakeholders, such as taxonomists, systematists, ecologists, niche modelers, informaticians and ontologists. The suggested use cases resulted in nine breakout groups addressing three main themes: i) mobilising heritage biodiversity knowledge; ii) formalising and linking concepts; and iii) addressing interoperability between service platforms. Another goal was to further foster a community of experts in biodiversity informatics and to build human links between research projects and institutions, in response to recent calls to further such integration in this research domain. Conclusions: Beyond deriving prototype solutions for each use case, areas of inadequacy were discussed and are being pursued further. It was striking how many possible applications for biodiversity data there were and how quickly solutions could be put together when the normal constraints to collaboration were broken down for a week. Conversely, mobilising biodiversity knowledge from their silos in heritage literature and natural history collections will continue to require formalisation of the concepts (and the links between them) that define the research domain, as well as increased interoperability between the software platforms that operate on these concepts.

Balech, Bachir; Beard, Niall; Blissett, Matthew; Brenninkmeijer, Christian; van Dooren, Tom; Eades, David; Gosline, George; Groom, Quentin John; Hamann, Thomas D.; Hettling, Hannes; Hoehndorf, Robert; Holleman, Ayco; Hovenkamp, Peter; Kelbert, Patricia; King, David; Kirkup, Don; Lammers, Youri; DeMeulemeester, Thibaut; Mietchen, Daniel; Miller, Jeremy A.; Mounce, Ross; Nicolson, Nicola; Page, Rod; Pawlik, Aleksandra; Pereira, Serrano; Penev, Lyubomir; Richards, Kevin; Sautter, Guido; Shorthouse, David Peter; Tahtinen, Marko; Weiland, Claus; Williams, Alan R.; Sierra, Soraya

2014-01-01

266

The contribution of land photosynthesis to the stationary enrichment of 18 O in the atmosphere  

Microsoft Academic Search

Summary The stationary enrichment of18O in the earth's atmosphere (Dole-effect) does not result exclusively from respiration processes, but also from photosynthesis in transpiring plants. Using the global distribution patterns of relative humidity, photosynthetic activity and H218O concentration in precipitation water, the contribution of land photosynthesis to the Dole-effect is estimated to 8 ‰.

G. Dongmann

1974-01-01

267

Natural phenomena hazards evaluation of equipment and piping of Gaseous Diffusion Plant Uranium Enrichment Facility  

Microsoft Academic Search

In support of the Gaseous Diffusion Plant Safety Analysis Report Upgrade program (GDP SARUP), a natural phenomena hazards evaluation was performed for the main process equipment and piping in the uranium enrichment buildings at Paducah and Portsmouth gaseous diffusion plants. In order to reduce the cost of rigorous analyses, the evaluation methodology utilized a graded approach based on an experience

M. K. Singhal; J. H. Kincaid; C. R. Hammond; B. I. Stockdale; J. C. Walls; W. R. Brock; D. R. Denton

1995-01-01

268

Enrichment and Purification of Total Chlorogenic Acids from Tobacco Waste Extract with Macroporous Resins  

Microsoft Academic Search

In the present study, an evaluation was conducted on the performance and separation characteristics of nine macroporous resins for the enrichment and purification of total chlorogenic acids from tobacco (Nicotiana tobaccum L.) waste extracts. Based on the results, XAD-4 offered higher adsorption and desorption capacities for total chlorogenic acids than other resins. To optimize the separation process of total chlorogenic

Zhao Hui; Wang Jun; Jia Jing; Liu Ji; Ling Xiuquan; Lu Dingqiang

2010-01-01

269

Ice-Enriched Loess and the Formation of Periglacial Terrain in Mid-Utopia Planitia, Mars  

NASA Astrophysics Data System (ADS)

Landforms suggestive of periglacial processes are commonplace in mid-Utopia Planitia, Mars. They form syngenetically in ground-ice comprised of loess transported by katabatic wind from the NPLDs and enriched by ice through the thaw-freeze cycling of obliquity-driven precipitation.

Soare, R. J.; Conway, S. J.; Pearce, G. D.; Costard, F.

2012-03-01

270

Enrichments of Cellulolytic Communities from Diverse Natural Sources Using a Novel Selection System  

NASA Astrophysics Data System (ADS)

In order to ensure a sustainable future and curb carbon dioxide emissions from the combustion of fossil fuels, it is imperative to develop a cost-competitive manufacturing process for an alternative liquid fuel with low life cycle greenhouse gas emissions. A potential route towards this sustainable future is the large-scale production of fuels derived from plant biomass, biofuels. A major step for the biological conversion of biomass to fuel is the solubilization and utilization of cellulose. However, lignocellulose is a recalcitrant material, and has evolved to resist microbial degradation. Studying cellulolytic communities from nature can reveal the mechanisms by which organisms can utilize lignocellulose, and also reveal the conditions that facilitate the fastest possible rates of cellulose utilization. This thesis used an Automated Repetitive Batch (ARB) system to perform enrichments of cellulolytic communities to test if cellulolytic communities from diverse sources could be reproducibly enriched for rapid cellulose utilization. This thesis first developed a robust method for reproducibly enriching cellulolytic communities in the ARB system with a single environmental source. Using this method, this research then investigated if cellulolytic communities could be enriched for rapid cellulose utilization from different inoculum sources. In all reproducible enrichments, this thesis then confirmed the use of carbon dioxide as a real time proxy for cellulose utilization based on end product analysis. This thesis showed that the ARB system could yield cellulolytic communities capable of rapid cellulose utilization from diverse environmental sources, and laid a strong foundation for determining whether or not these different sources can be enriched to yield functionally similar cellulolytic communities. The work from this thesis also suggests that fermentation conditions, rather than source material, play a more important role in determining enriched community performance.

Ludwig, Evan Joel

271

DEFOG: Discrete Enrichment of Functionally Organized Genes†  

PubMed Central

High-throughput biological experiments commonly result in a list of genes or proteins of interest. In order to understand the observed changes of the genes and to generate new hypotheses, one needs to understand the functions and roles of the genes and how those functions relate to the experimental conditions. Typically, statistical tests are performed in order to detect enriched Gene Ontology categories or Pathways, i.e. the categories are observed in the genes of interest more often than is expected by chance. Depending on the number of genes and the complexity and quantity of functions in which they are involved, such an analysis can easily result in hundreds of enriched terms. To this end we developed DEFOG, a web-based application that facilitates the functional analysis of gene sets by hierarchically organizing the genes into functionally related modules. Our computational pipeline utilizes three powerful tools to achieve this goal: (1) GeneMANIA creates a functional consensus network of the genes of interest based on gene-list-specific data fusion of hundreds of genomic networks from publicly available sources; (2) Transitivity Clustering organizes those genes into a clear hierarchy of functionally related groups, and (3) Ontologizer performs a Gene Ontology enrichment analysis on the resulting gene clusters. DEFOG integrates this computational pipeline within an easy-to-use web interface, thus allowing for a novel visual analysis of gene sets that aids in the discovery of potentially important biological mechanisms and facilitates the creation of new hypotheses. DEFOG is available at http://www.mooneygroup.org/defog.

Wittkop, Tobias; Berman, Ari E.; Fleisch, K. Mathew; Mooney, Sean D.

2012-01-01

272

Uranium Enrichment - ChemCases.com  

NSDL National Science Digital Library

Natural uranium contains 0.7205% of the U-235, the fissile isotope of uranium. There are a few U-234 atoms (0.0055%) in the remaining mass of U-238 (99.274%). Uranium-238 does not contribute to slow neutron fission; however, it does react with neutrons to form a fissile isotope of plutonium, Pu-239. Although U-235 and U-238 are chemically identical, they differ slightly in their physical properties, most importantly mass. This small mass difference allows the isotopes to be separated and makes it possible to increase ("enrich") the percentage of U-235 in uranium.

Settle, Frank

273

Mineralization of trichloroethylene by heterotrophic enrichment cultures  

SciTech Connect

Microbial consortia capable of aerobically degrading greater than 99% of 50 mg/l exogenous trichloroethylene (TCE) have been enriched from TCE contaminated subsurface sediments. Concentrations of TCE greater than 300 mg/l were not degraded nor was TCE used as a sole energy source. Successful electron donors for growth included tryptone-yeast extract, methanol, methane or propane. The optimum temperature for growth was 22--37 C and the ph optimum was 7.0--8.1. Utilization of TCE occurred only after apparent microbial growth had ceased. The major end products recovered were hydrochloric acid and carbon dioxide. Minor products included dichloroethylene, vinylidine chloride and possibly chloroform.

Phelps, T.J.; Ringelberg, D.; Mikell, A.T.; White, D.C. [Univ. of Tennessee, Knoxville, TN (United States). Inst. for Applied Microbiology]|[Oak Ridge National Lab., Knoxville, TN (United States); Fliermans, C.B. [E.I. DuPont de Nemours and Co., Aiken, SC (United States). Savannah River Lab.

1988-12-31

274

Hydrogen-enrichment-concept preliminary evaluation  

NASA Technical Reports Server (NTRS)

A hydrogen-enriched fuels concept for automobiles is described and evaluated in terms of fuel consumption and engine exhaust emissions through multicylinder (V-8) automotive engine/hydrogen generator tests, single cylinder research engine (CFR) tests, and hydrogen-generator characterization tests. Analytical predictions are made of the fuel consumption and NO/sub x/ emissions which would result from anticipated engine improvements. The hydrogen-gas generator, which was tested to quantify its thermodynamic input-output relationships was used for integrated testing of the V-8 engine and generator.

Ecklund, E. E.

1975-01-01

275

Active interrogation of highly enriched uranium  

NASA Astrophysics Data System (ADS)

Safeguarding special nuclear material (SNM) in the Department of Energy Complex is vital to the national security of the United States. Active and passive nondestructive assays are used to confirm the presence of SNM in various configurations ranging from waste to nuclear weapons. Confirmation measurements for nuclear weapons are more challenging because the design complicates the detection of a distinct signal for highly enriched uranium. The emphasis of this dissertation was to investigate a new nondestructive assay technique that provides an independent and distinct signal to confirm the presence of highly enriched uranium (HEU). Once completed and tested this assay method could be applied to confirmation measurements of nuclear weapons. The new system uses a 14-MeV neutron source for interrogation and records the arrival time of neutrons between the pulses with a high efficiency detection system. The data is then analyzed by the Feynman reduced variance method. The analysis determined the amount of correlation in the data and provided a unique signature of correlated fission neutrons. Measurements of HEU spheres were conducted at Los Alamos with the new system. Then, Monte Carlo calculations were performed to verify hypothesis made about the behavior of the neutrons in the experiment. Comparisons of calculated counting rates by the Monte Carlo N-Particle Transport Code (MCNP) were made with the experimental data to confirm that the measured response reflected the desired behavior of neutron interactions in the highly enriched uranium. In addition, MCNP calculations of the delayed neutron build-up were compared with the measured data. Based on the results obtained from this dissertation, this measurement method has the potential to be expanded to include mass determinations of highly enriched uranium. Although many safeguards techniques exist for measuring special nuclear material, the number of assays that can be used to confirm HEU in shielded systems is limited. These assays also rely on secondary characteristics of the material to be measured. A review of the nondestructive techniques with potential applications for nuclear weapons confirmatory measurements were evaluated with summaries of the pros and cons involved in implementing the methods at production type facilities.

Fairrow, Nannette Lea

276

Flight opportunities for science teacher enrichment  

NASA Technical Reports Server (NTRS)

NASA Astrophysics Division supports a pre-college teacher program to provide Flight Opportunities for Science Teacher EnRichment (FOSTER). To date, forty-five teachers are participating, and the program will expand nation-wide to serve fifty teachers per year on board the Kuiper Airborne Observatory. In the future, the Stratospheric Observatory for Infrared Astronomy (SOFIA) will bring more than one-hundred teachers per year on board for astronomical research mission. FOSTER is supported by a grant to the SETI Institute from the NASA Astrophysics Division, NAGW-3291.

Devore, Edna; Gillespie, Carlton, Jr.; Hull, Garth; Koch, David

1995-01-01

277

Dietary fiber-enriching agent and dietary fiber-enriched food  

US Patent & Trademark Office Database

The invention provides a water-soluble dietary fiber enriching agent comprising a modified starch which contains dietary fibers in an amount not more than 5% by mass measured by Prosky's method and a low-molecular weight water-soluble dietary fiber in an amount not less than 25% by mass. The water-soluble dietary fiber enriching agent contains a low-molecular weight water-soluble dietary fiber, and does not deteriorate the mouthfeel of the food obtained using the same.

2013-02-19

278

PREPARING THE HIGH FLUX ISOTOPE REACTOR FOR CONVERSION TO LOW ENRICHED URANIUM FUEL ? EXTENDING CYCLE BURNUP  

SciTech Connect

Reactor performance studies have been completed for conceptual plate designs and show that maintaining reactor performance while converting HFIR from high enriched to low enriched uranium (20 wt % 235U) fuel requires extending the end-of-life burnup value for HFIR fuel from the current nominal value of 2200 MWD to 2600 MWD. The current fuel fabrication procedure is discussed and changes that would be required to this procedure are identified. Design and safety related analyses that are required for the certification of a new fuel are identified. Qualification tests and comments regarding the regulatory approval process are provided along with a conceptual schedule.

Primm, Trent [ORNL; Chandler, David [ORNL

2009-01-01

279

Selective Recovery of Enriched Uranium from Inorganic Wastes  

SciTech Connect

Uranium as U(IV) and U(VI) can be selectively recovered from liquids and sludge containing metal precipitates, inorganic salts, sand and silt fines, debris, other contaminants, and slimes, which are very difficult to de-water. Chemical processes such as fuel manufacturing and uranium mining generate enriched and natural uranium-bearing wastes. This patented Framatome ANP (FANP) uranium recovery process reduces uranium losses, significantly offsets waste disposal costs, produces a solid waste that meets mixed-waste disposal requirements, and does not generate metal-contaminated liquids. At the head end of the process is a floating dredge that retrieves liquids, sludge, and slimes in the form of a slurry directly from the floor of a lined surface impoundment (lagoon). The slurry is transferred to and mixed in a feed tank with a turbine mixer and re-circulated to further break down the particles and enhance dissolution of uranium. This process uses direct steam injection and sodium hypochlorite addition to oxidize and dissolves any U(IV). Cellulose is added as a non-reactive filter aid to help filter slimes by giving body to the slurry. The slurry is pumped into a large recessed-chamber filter press then de-watered by a pressure cycle-controlled double-diaphragm pump. U(VI) captured in the filtrate from this process is then precipitated by conversion to U(IV) in another Framatome ANP-patented process which uses a strong reducing agent to crystallize and settle the U(IV) product. The product is then dewatered in a small filter press. To-date, over 3,000 Kgs of U at 3% U-235 enrichment were recovered from a 8100 m2 hypalon-lined surface impoundment which contained about 10,220 m3 of liquids and about 757 m3 of sludge. A total of 2,175 drums (0.208 m3 or 55 gallon each) of solid mixed-wastes have been packaged, shipped, and disposed. In addition, 9463 m3 of low-U liquids at <0.001 KgU/m3 were also further processed and disposed.

Kimura, R. T.

2003-02-26

280

Highly efficient enrichment method for glycopeptide analyses: using specific and nonspecific nanoparticles synergistically.  

PubMed

We invented a new method for highly efficient and specific enrichment of glycopeptides using two different nanomaterials synergistically. One is boronic-acid-functionalized Fe3O4 nanoparticles, enriching glycopeptides through formation of cyclic boronate esters between the boronic acid groups and the cis-diol groups on glycopeptides. The other nanomaterial is conventional poly(methyl methacrylate) nanobeads, which have strong adsorption toward nonglycopeptides. By optimizing the proportion of these two materials, extremely high sensitivity and selectivity are achieved in analyzing the standard glycopeptides/nonglycopeptides mixture solutions. Since the washing step is not necessary for these conditions, the enrichment process is simplified and the recovery efficiency of target glycopeptides reaches 90%. Finally, this approach is successfully applied to analyze human serum with the sample volume as little as 1 ?L, in which 147 different N-glycosylation peptides within 66 unique glycoproteins are identified. All these performances by the synergistic enrichment are much better than employing one specific enrichment agent alone. PMID:24471740

Wang, Yali; Liu, Minbo; Xie, Liqi; Fang, Caiyun; Xiong, Huanming; Lu, Haojie

2014-02-18

281

Testing for efficacy in adaptive clinical trials with enrichment.  

PubMed

Adaptive design of clinical trials has attracted considerable interest because of its potential of reducing costs and saving time in the clinical development process. In this paper, we consider the problem of assessing the effectiveness of a test treatment over a control by a two-arm randomized clinical trial in a potentially heterogenous patient population. In particular, we study enrichment designs that use accumulating data from a clinical trial to adaptively determine patient subpopulation in which the treatment effect is eventually assessed. A hypothesis testing procedure and a lower confidence limit are presented for the treatment effect in the selected patient subgroups. The performances of the new methods are compared with existing approaches through a simulation study. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24577792

Wu, Samuel S; Tu, Yi-Hsuan; He, Ying

2014-07-20

282

Galaxy formation and chemical enrichment using cosmological hydrodynamic simulations  

NASA Astrophysics Data System (ADS)

Structure formation in the Universe is inherently a nonlinear physical process, and the field of computational cosmology aims to study its time evolution throughout the history of the Universe as self-consistently as possible. Cosmological hydrodynamic simulations have gone through two major revolutions over the last two decades, and now starting to go through the third one via more frequent usage of zoom-in technique. In the first part of this article, I briefly review the history of computational cosmology. In the second part, I discuss the results of recent work on the feedback effects and chemical enrichment, which is one of the main topics of this OMEG12 conference. Finally, I describe the new steps that the numerical community is taking; namely the numerical simulation comparison projects such as the AGORA project.

Nagamine, Kentaro

2014-05-01

283

Successful brain aging: plasticity, environmental enrichment, and lifestyle.  

PubMed

Aging is a physiological process that can develop without the appearance of concurrent diseases. However, very frequently, older people suffer from memory loss and an accelerated cognitive decline. Studies of the neurobiology of aging are beginning to decipher the mechanisms underlying not only the physiology of aging of the brain but also the mechanisms that make people more vulnerable to cognitive dysfunction and neurodegenerative diseases. Today we know that the aging brain retains a considerable functional plasticity, and that this plasticity is positively promoted by genes activated by different lifestyle factors. In this article some of these lifestyle factors and their mechanisms of action are reviewed, including environmental enrichment and the importance of food intake and some nutrients. Aerobic physical exercise and reduction of chronic stress are also briefly reviewed. It is proposed that lifestyle factors are powerful instruments to promote healthy and successful aging of the brain and delay the appearance of age-related cognitive deficits in elderly people. PMID:23576888

Mora, Francisco

2013-03-01

284

Microbial community composition in sediments resists perturbation by nutrient enrichment  

PubMed Central

Functional redundancy in bacterial communities is expected to allow microbial assemblages to survive perturbation by allowing continuity in function despite compositional changes in communities. Recent evidence suggests, however, that microbial communities change both composition and function as a result of disturbance. We present evidence for a third response: resistance. We examined microbial community response to perturbation caused by nutrient enrichment in salt marsh sediments using deep pyrosequencing of 16S rRNA and functional gene microarrays targeting the nirS gene. Composition of the microbial community, as demonstrated by both genes, was unaffected by significant variations in external nutrient supply in our sampling locations, despite demonstrable and diverse nutrient-induced changes in many aspects of marsh ecology. The lack of response to external forcing demonstrates a remarkable uncoupling between microbial composition and ecosystem-level biogeochemical processes and suggests that sediment microbial communities are able to resist some forms of perturbation.

Bowen, Jennifer L; Ward, Bess B; Morrison, Hilary G; Hobbie, John E; Valiela, Ivan; Deegan, Linda A; Sogin, Mitchell L

2011-01-01

285

An immunomagnetic epithelial tumor cell enrichment model for minimal residual disease detection of cytokeratin 8+ malignancies.  

PubMed

Immunocytochemical detection of isolated tumor cells in peripheral blood and bone marrow is currently the most established method for monitoring early dissemination in epithelial cancer. In this study we used an immunomagnetic selection technique to develop an enrichment model for disseminated tumor cells in blood. Buffy coat cells spiked with varying numbers of BT-474 carcinoma cells were permeabilized and fixed, following which carcinoma cells were magnetically labelled with an anti-cytokeratin 8 mAb. Labelled cells were enriched by the use of magnetic columns. The eluted cytokeratin 8+ tumor cells were detected by flow cytometry and immunocytochemistry. Spiked samples were split and processed freshly in the immunomagnetic enrichment assay, as well as cryopreserved and processed in the assay after thawing. Enumeration of BT-474 cells demonstrated a detection limit of one BT-474 cell in 1.0 x 10(7) leukocytes in both fresh and cryopreserved-thawed samples. The pair wise comparison showed a significantly higher recovery of spiked BT-474 cells from freshly processed samples than from cryopreserved and thawed samples (57% vs 21%). Viability tests suggested that this outcome might be due to a greater susceptibility of BT-474 cells than buffy coat cells to the used cryopreservation and thawing technique. Altogether our findings show that the performance of the immunomagnetic enrichment assay on fresh samples is satisfactory with a recovery rate of almost 60% and a sensitivity of 10(-7). However, performance of the assay on cryopreserved and thawed cells needs to be improved. PMID:16178280

Brooimans, R A; de Leeuw, N; Bontenbal, M; Gratama, J W

2005-01-01

286

The sea surface microlayer: Biology, chemistry and anthropogenic enrichment  

NASA Astrophysics Data System (ADS)

Recent studies increasingly point to the interface between the world's atmosphere and hydrosphere (the sea-surface microlayer) as an important biological habitat and a collection point for anthropogenic materials. Newly developed sampling techniques collect different qualitative and quantitative fractions of the upper sea surface from depths of less than one micron to several centimeters. The microlayer provides a habitat for a biota, including the larvae of many commercial fishery species, which are often highly enriched in density compared to subsurface water only a few cm below. Common enrichments for bacterioneuston, phytoneuston, and zooneuston are 10 2-10 4, 1-10 2, and 1-10, respectively. The trophic relationships or integrated functioning of these neustonic communities have not been examined. Surface tension forces provide a physically stable microlayer, but one which is subjected to greater environmental and climatic variation than the water column. A number of poorly understood physical processes control the movement and flux of materials within and through the microlayer. The microlayer is generally coated with a natural organic film of lipid and fatty acid material overlying a polysaccharide protein complex. The microlayer serves as both a source and a sink for materials in the atmosphere and the water column. Among these materials are large quantities of anthropogenic substances which frequently occur at concentrations 10 2-10 4 greater than these in the water column. These include plastics, tar lumps, polyaromatic hydrocarbons, chlorrinated hydrocarbons, and potentially toxic metals, such as, lead, copper, zinc, and nickel. How the unique processes occurring in the microlayer affect the fate of anthropogenic substances is not yet clear. Many important questions remain to be examined.

Hardy, J. T.

287

75 FR 62895 - Notice of Availability of Safety Evaluation Report; AREVA Enrichment Services LLC, Eagle Rock...  

Federal Register 2010, 2011, 2012, 2013

...AREVA Enrichment Services LLC, Eagle Rock Enrichment Facility, Bonneville County...Senior Project Manager, Advanced Fuel Cycle, Enrichment, and Uranium Conversion...proposed facility is known as the Eagle Rock Enrichment Facility (EREF) and...

2010-10-13

288

Gender-Dependent Effects of Enriched Environment and Social Isolation in Ischemic Retinal Lesion in Adult Rats  

PubMed Central

Exposure to an enriched environment has been shown to have many positive effects on brain structure and function. Numerous studies have proven that enriched environment can reduce the lesion induced by toxic and traumatic injuries. Impoverished environment, on the other hand, can have deleterious effects on the outcome of neuronal injuries. We have previously shown that enriched conditions have protective effects in retinal injury in newborn rats. It is well-known that the efficacy of neuroprotective strategies can depend on age and gender. The aim of the present study, therefore, was to examine the effects of environmental enrichment and social isolation in retinal ischemia. We used bilateral common carotid artery occlusion to induce retinal hypoperfusion in adult Wistar rats of both genders. Groups were housed in standard, enriched or impoverished conditions. Impoverished environment was induced by social isolation. Retinas were processed for histological analysis after two weeks of survival. In the present study, we show that (1) enriched environment has protective effects in adult ischemic retinal lesion, while (2) impoverished environment further increases the degree of ischemic injury, and (3) that these environmental effects are gender-dependent: females are less responsive to the positive effects of environmental enrichment and more vulnerable to retinal ischemia in social isolation. In summary, our present study shows that the effects of both positive and negative environmental stimuli are gender-dependent in ischemic retinal lesions.

Kiss, Peter; Szabadfi, Krisztina; Horvath, Gabor; Tamas, Andrea; Farkas, Jozsef; Gabriel, Robert; Reglodi, Dora

2013-01-01

289

Production of fuel products by the thermal dissolution of enriched Baltic combustible shale  

SciTech Connect

The thermal dissolution of enriched Baltic shale (kerogen-70) in the presence of an organosilicon compound reduces the formation of gas and raises the solubility of its organic matter and, when the sludge from the process is coked, it decreases the formation of semicoke and gas; as a result of this, the yield of liquid products calculated on the shale processed is increased one and a half times.

Vol-Epshtein, A.B.; Gorlov, E.G.; Shpilberg, M.B.

1983-01-01

290

OnTarget: A tool for analysing enrichment data derived from next generation sequencing  

Microsoft Academic Search

We have developed OnTarget, a pipeline which is designed to evaluate next generation sequencing data after sub-genomic enrichment. It is able to process single-end and paired-end sequence reads as well as single-end bisulfite data. Sequence reads can be sorted by barcodes and are mapped against the genome. Only reads which map once are processed, subsequently removing duplicate reads and finally

Agnes Hotz-Wagenblatt; Ilia Kats; Karl-Heinz Glatting; Maren Scharfenberger-Schmeer; Berit Haldemann

2011-01-01

291

Enrichment of By-Product Materials from Steel Pickling Acid Regeneration Plants (TRP 9942)  

Microsoft Academic Search

A new process for manufacturing an enriched, iron-based product (strontium hexaferrite) in existing steel pickling acid regeneration facilities was evaluated. Process enhancements and equipment additions were made to an existing acid regeneration plant to develop and demonstrate (via pilot scale testing and partial-capacity production trials) the viability of a patented method to produce strontium-based compounds that, when mixed with steel

Lu Swan; Delta Ferrites LLC

2009-01-01

292

Rare-earth elements enrichment of Pacific seafloor sediments: the view from volcanic islands of Polynesia  

NASA Astrophysics Data System (ADS)

Rare-earth elements (REEs) are key metals for «green» technologies such as energy saving lamps or permanent magnets used in, e.g., wind turbines, hard disk drives, portable phone or electric or hybrid vehicles. Since several years, world demand for these metals is therefore drastically increasing. The quasi-monopolistic position of China, which produces around 95 % of global REEs production, generates risks for the industries that depend on a secure supply of REEs. In response, countries are developing and diversifying their supply sources, with new mining projects located outside China and efforts in the area of REEs recycling. Most of these projects focus on deposits related to carbonatites and alkaline-peralkaline magmatism, which are generally enriched in light REEs (LREEs) compared to the heavy REEs (HREEs)-enriched deposits of the ion-adsorption types, located in southern China. However, a recent study revealed new valuable resources corresponding to seafloor sediments located in the south-eastern and north-central Pacific. The deep-sea mud described by these authors show a higher HREE/LREE ratio than ion-adsorption deposits, a feature which significantly increases their economic interest. The authors suggest mid-ocean ridge hydrothermal activity as an explanation to this anomalous enrichment. However, several contributions have documented considerable REEs enrichment in basalts and peridotitic xenoliths from French Polynesia. Several arguments have been exposed in favour of a supergene origin, with a short migration, suggesting that REEs were collected from weathered basalts. The Tahaa volcanic island (Sous-le-Vent Island, Society Archipelago, French Polynesia) is the first location where such enrichment has been described. New petrographic and mineralogical investigations confirm a supergene mobilization of this abnormal occurrence. REE-bearing minerals (mainly phosphates of the rhabdophane group) are primarily located within basalt vesicles but also in crack that cross-cut the calcite filling the vesicles or the volcanic glass. They are also closely associated with Ni-Mg bearing phyllosilicates, which appear to nucleate from alteration of olivine and clinopyroxenes. Further investigations are done to evidence and confirm an anterior magmatic enrichment. On the basis of these observations, we believe that the anomalous enrichment observed in seafloor sediments could derive from abnormally-rich provinces corresponding to aerial basaltic formations from oceanic islands primarily enriched during weathering processes (Melleton et al., 2014). Melleton et al. (2014). Rare-earth elements enrichment of Pacific sea-floor sediments: the view from volcanic islands of Polynesia. In preparation.

Melleton, Jérémie; Tuduri, Johann; Pourret, Olivier; Bailly, Laurent; Gisbert, Thierry

2014-05-01

293

Assuaging Nuclear Energy Risks: The Angarsk International Uranium Enrichment Center  

SciTech Connect

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.

Myers, Astasia [Stanford University, Stanford, CA 94305, USA and MonAme Scientific Research Center, Ulaanbaatar (Mongolia)

2011-06-28

294

Environmental enrichment: effects on stereotyped behavior and dendritic morphology.  

PubMed

We evaluated whether environmental enrichment-related effects on the development of stereotyped behavior in deer mice were associated with alterations in dendritic morphology. Deer mice were reared under enriched or standard housing conditions and then tested in automated photocell detectors and classified as stereotypic or nonstereotypic. Dendritic morphology was assessed in layer V pyramidal neurons of the motor cortex, medium spiny neurons of the dorsolateral striatum, and granule cells of the dentate gyrus using Golgi-Cox histochemistry. Enriched nonstereotypic mice exhibited significantly higher dendritic spine densities in the motor cortex and the striatum than enriched stereotypic or standard-cage mice. Significant increases in dendritic arborization following environmental enrichment also were observed. These results suggest that the enrichment-related prevention of stereotyped behavior is associated with increased dendritic spine density. PMID:12794775

Turner, Cortney A; Lewis, Mark H; King, Michael A

2003-07-01

295

University of Cambridge : Mathematics Enrichment (nrich)  

NSDL National Science Digital Library

University of Cambridge offers this website, Mathematics Enrichment (nrich), with problems, games and articles on mathematics for students ages 5 to 19. The problems are organized by Tiers (1 to 3) and follow the UK education system, but a guide for international educators is given in the Help section. Each problem includes a question, related resources, pictures or diagrams, a form for students to submit their solution, hints for students having difficulty, and notes for parents and teachers. The website is updated monthly and offers a weekly problem. This months theme is the mathematics of making journeys, with the path of the Olympic Torch as an intriguing lead-in to the topic. Registered users can pose questions and post messages in the discussion forum, both of which are also viewable by non-registered viewers. Registration is simple and does not cost anything.

2007-12-12

296

Enriched Storable Oxidizers for Rocket Engines  

NASA Technical Reports Server (NTRS)

The name "enriched storable oxidizers" (ESOs) has been coined for a family of optimized mixtures of between two and four oxidizer fluids. For most applications, the constituents of these mixtures would be nitrogen tetroxide (N2O4), nitrous oxide (N2O), and nitrogen dioxide (NO2); in some applications, the mixtures might include inhibited red fuming nitric acid [IRFN (which consists of red fuming nitric acid to which some hydrogen fluoride is added to reduce its corrosive effect]. The optimum proportions of these constituents would be different for different applications. ESOs were originally proposed for use in spacecraft and launch-rocket propulsion systems: ESOs could be especially useful in advanced spacecraft propulsion systems that could operate in multiple modes. ESOs might also be useful in special terrestrial applications that could include ramjet and scramjet aircraft engines.

Sackheim, R. L.; Herdy, J. R., Jr.

2010-01-01

297

Uranium enrichment decontamination and decommissioning fund  

SciTech Connect

One of the most challenging issues facing the Department of Energy`s Office of Environmental Management is the cleanup of the three gaseous diffusion plants. In October 1992, Congress passed the Energy Policy Act of 1992 and established the Uranium Enrichment Decontamination and Decommissioning Fund to accomplish this task. This mission is being undertaken in an environmentally and financially responsible way by: devising cost-effective technical solutions; producing realistic life-cycle cost estimates, based on practical assumptions and thorough analysis; generating coherent long-term plans which are based on risk assessments, land use, and input from stakeholders; and, showing near-term progress in the cleanup of the gaseous diffusion facilities at Oak Ridge.

NONE

1994-12-31

298

University of Cambridge: Mathematics Enrichment (nrich)  

NSDL National Science Digital Library

University of Cambridge offers this website, Mathematics Enrichment (nrich), with problems, games and articles on mathematics for students ages 5 to 19. The problems are organized by Tiers (1 to 3) and follow the UK education system, but a guide for international educators is given in the Help section. Each problem includes a question, related resources, pictures or diagrams, a form for students to submit their solution, hints for students having difficulty, and notes for parents and teachers. The website is updated monthly and offers a weekly problem. This months' theme is "the mathematics of making journeys," with the path of the Olympic Torch as an intriguing lead-in to the topic. Registered users can pose questions and post messages in the discussion forum, both of which are also viewable by non-registered viewers. Registration is simple and does not cost anything.

299

Acoustically enriching, large-depth aquatic sampler.  

PubMed

In marine biology, it is useful to collect water samples when exploring the distribution and diversity of microbial communities in underwater environments. In order to provide, e.g., a miniaturized submersible explorer with the capability of collecting microorganisms, a compact sample enrichment system has been developed. The sampler is 30 mm long, 15 mm wide, and just a few millimetres thick. Integrated in a multilayer steel, polyimide and glass construction is a microfluidic channel with piezoelectric transducers, where microorganism and particle samples are collected and enriched, using acoustic radiation forces for gentle and labelless trapping. High-pressure, latchable valves, using paraffin as the actuation material, at each end of the microfluidic channel keep the collected sample pristine. A funnel structure raised above the surface of the device directs water into the microfluidic channel as the vehicle propels itself or when there is a flow across its hull. The valves proved leak proof to a pressure of 2.1 MPa for 19 hours and momentary pressures of 12.5 MPa, corresponding to an ocean depth of more than 1200 metres. By reactivating the latching mechanism, small leakages through the valves could be remedied, which could thus increase the leak-less operational time. Fluorescent particles, 1.9 ?m in diameter, were successfully trapped in the microfluidic channel at flow rates up to 15 ?l min(-1), corresponding to an 18.5 cm s(-1) external flow rate of the sampler. In addition, liquid-suspended GFP-marked yeast cells were successfully trapped. PMID:22422039

Jonsson, Jonas; Ogden, Sam; Johansson, Linda; Hjort, Klas; Thornell, Greger

2012-05-01

300

Trace metal enrichments in waters of the Gulf of Cadiz, Spain  

NASA Astrophysics Data System (ADS)

Dissolved Cu, Cd, and Zn concentrations in continental shelf waters of the Gulf of Cadiz are much higher than reported for other coastal areas. Direct observations of the metal enrichments in this region were made in March-April 1986 and October 1986; indirect observations (in the Alboran Sea) suggest similar enrichments occurred in June 1982 and September 1980, and it is probable that these enrichments are a persistent feature of the region. Zinc concentrations varied by more than two orders of magnitude between Atlantic water entering the Strait of Gibraltar (<1 nmol/kg) and Spanish shelf water (up to 160 nmol/kg). Copper and cadmium were also highly enriched in Spanish shelf water (up to 47 and 1.3 nmol/kg, respectively), and concentrations of these metals varied co-linearly with Zn. Chemical profiles show that metal enrichments over the Spanish shelf extended from the surface down to about a 45 m depth. In contrast, Ni, phosphate, silicate, and 228Ra/ 226Ra all occurred at levels typical of other shelf waters. Copper, cadmium, and zinc concentrations in nearby Moroccan shelf water were only a factor of 2 to 3 higher than off-shore surface Atlantic water. A steep surface Cu, Cd, and Zn concentration gradient was observed in the axis of the Strait of Gibraltar denoting the boundary between off-shore Atlantic and Spanish shelf water. Metal:metal and metal:salinity relationships immediately west of the Strait of Gibraltar show that variations in the composition of surface water can be described by conservative mixing of three sources: (1) metal-depleted surface Atlantic water, (2) Spanish shelf water, highly enriched in Cu, Cd, and Zn, and (3) subsurface North Atlantic Central Water, enriched in Cd and slightly enriched in Ni. Because the Atlantic inflow through the Strait is the main water source for the Mediterranean Sea, enrichments in the Gulf of Cadiz influence metal concentrations of the whole basin. Some temporal metal variation is observed in Spanish shelf water: Zn concentrations decreased by a factor of two between April and October 1986. Although metal concentrations increase systematically with decreasing salinity over the Spanish shelf, Iberian rivers cannot account for the Cu, Cd, and Zn enrichments. An anthropogenic source of any type seems unlikely because the loss of Cu, Cd, and Zn by entrainment of shelf water through the Strait of Gibraltar is equivalent to a significant fraction of total metal consumption on the Iberian peninsula. A diagenetic shelf sediment source may be more plausible, but it would have to be of much greater magnitude than on other shelves. One mechanism that may enhance metal fluxes from shelf sediments is a coastal "metal trap" driven by an estuarine-type circulation pattern and biological production along the Iberian coast. This process is illustrated here by a simple box model; if this process occurs along the whole Iberian peninsula, Cd enrichments (but perhaps only part of the observed Cu or Zn enrichments) could be sustained against the considerable advective metal sink through the Strait of Gibraltar.

Van Geen, Alexander; Boyle, Edward A.; Moore, Willard S.

1991-08-01

301

Confronting the Paradox of Enrichment to the Metacommunity Perspective  

PubMed Central

Resource enrichment can potentially destabilize predator-prey dynamics. This phenomenon historically referred as the "paradox of enrichment" has mostly been explored in spatially homogenous environments. However, many predator-prey communities exchange organisms within spatially heterogeneous networks called metacommunities. This heterogeneity can result from uneven distribution of resources among communities and thus can lead to the spreading of local enrichment within metacommunities. Here, we adapted the original Rosenzweig-MacArthur predator-prey model, built to study the paradox of enrichment, to investigate the effect of regional enrichment and of its spatial distribution on predator-prey dynamics in metacommunities. We found that the potential for destabilization was depending on the connectivity among communities and the spatial distribution of enrichment. In one hand, we found that at low dispersal regional enrichment led to the destabilization of predator-prey dynamics. This destabilizing effect was more pronounced when the enrichment was uneven among communities. In the other hand, we found that high dispersal could stabilize the predator-prey dynamics when the enrichment was spatially heterogeneous. Our results illustrate that the destabilizing effect of enrichment can be dampened when the spatial scale of resource enrichment is lower than that of organismss movements (heterogeneous enrichment). From a conservation perspective, our results illustrate that spatial heterogeneity could decrease the regional extinction risk of species involved in specialized trophic interactions. From the perspective of biological control, our results show that the heterogeneous distribution of pest resource could favor or dampen outbreaks of pests and of their natural enemies, depending on the spatial scale of heterogeneity.

Hauzy, Celine; Nadin, Gregoire; Canard, Elsa; Gounand, Isabelle; Mouquet, Nicolas; Ebenman, Bo

2013-01-01

302

Selective Enrichment of Two Different Types of Nitrospira-like Nitrite-oxidizing Bacteria from a Wastewater Treatment Plant  

PubMed Central

Nitrification is an important step in nitrogen removal in biological wastewater treatment processes. Recently, Nitrospira have been recognized as the numerically dominant nitrite-oxidizing bacterial genus primarily responsible for the second step of aerobic nitrification; however, Nitrospira usually resist cultivation under laboratory conditions and only one species enriched from activated sludge has been described. In this study, a novel enrichment method for Nitrospira was successfully developed using continuous feeding bioreactors. By controlling nitrite concentrations strictly in the bioreactor at low levels below 10 mg-N L?1, coexisting members of sublineages I and II of the genus Nitrospira were enriched selectively. The maximum ratios of sublineages I and II to total microbial cells achieved 88.3% and 53.8%, respectively. This enrichment method is potentially applicable to other uncultured Nitrospira.

Fujitani, Hirotsugu; Aoi, Yoshiteru; Tsuneda, Satoshi

2013-01-01

303

Thermal enrichment and speciation of copper in rice husk ashes.  

PubMed

Copper(II) was considerably enriched in the residual ash via thermal treatment of copper-sorbed rice husk at 700-1100°C for 2h, and the copper speciation was quantitatively determined with X-ray absorption spectroscopy. After the thermal process, the resulting ash only represents by weight 18.7-26.4% of the pre-heated samples. Copper content in the ashes is >7% which is far above the required minimum copper content in copper ores for the copper smelting sector, 0.5%. Crystalline SiO(2) is observed only in the ash generated at 1100°C, with more copper in this ash being available for leaching in acidic solution. It is suggested that this is due to the considerable dissimilarity in crystalline structure between copper compounds and crystalline SiO(2). No chemical reaction between copper and SiO(2) is observed in any ash. In fact, we suggest that the SiO(2) crystalline phase repels copper during the thermal process; this would make it easy to extract copper from the ashes. For copper speciation in the ashes, CuO merely represents 0-12% of the total copper, while Cu(2)O and Cu(0) represent 34-42% and 46-63%, respectively. The lower copper oxidation state would be beneficial for the copper smelting process due to less usage of coke. PMID:20869164

Wei, Yu-Ling; Hu, Ming-Jan; Peng, Yen-Hsun

2010-12-15

304

[Selenium enriched spirulina and phycocyanin are sources of bioavailable selenium].  

PubMed

Rats were fed for two weeks low-selenium semi-synthetic diet supplemented with different sources of selenium: sodium selenite (selenium concentration 96 and 350 mcg/kg diet), selenium-enriched Spirulina (selenium concentration 350 mcg/kg diet) and selenium-enriched Phycocyanin (selenium concentration 96 mcg/kg diet). Selenium bioavailability was evaluated in terms of selenium accumulation in blood and liver as well as glutathione peroxidase activity. It was shown that selenium from selenium-enriched Spirulina and selenium-enriched phycocyanin was high bioavailable in rats. PMID:18839810

Kravchenko, L V; Gladkikh, O L; Gmoshinski?, I V; Mazo, V K

2008-01-01

305

Contaminant enrichment and properties of soil adhering to skin  

SciTech Connect

The adhesion of contaminated soil to skin has potentially important health implications, because the contaminants may ultimately be ingested or absorbed through the skin. Previous studies indicated that the adhering soil is enriched in contaminant concentration relative In the original soil because of the selective adhesion of finer particles. This study investigated this enrichment using 11 markedly different soils. Two sandy soils consistently gave very high contaminant enrichment ratios, with a mean enrichment of 10-fold. The other soils all had enrichment ratios above unity. Scanning electron microscopy illustrated the potential for strong adhesion of very fine clay particles. The contaminant enrichment ratios were positively correlated to enrichments in specific surface area, organic matter content, and extractable Fe content. Correlations to soil textural properties and detailed particle-size analysis of the adhering soil indicated that 50 to 100 {mu}m may be a critical particle size: larger grains and aggregates do not adhere readily to skin. Because of this, enrichment ratios will vary positively with the proportion of particles in the whole soil that am greater than 50 {mu}m. A simple model is provided to predict enrichments using information from routine soil particle-size analysis. 44 refs., 4 figs., 4 tabs.

Sheppard, S.C.; Evenden, W.G. [Whiteshell Labs., Pinawa (Canada)

1994-05-01

306

A Method for Selective Enrichment and Analysis of Nitrotyrosine-Containing Peptides in Complex Proteome Samples  

SciTech Connect

Elevated levels of protein tyrosine nitration have been found in various neurodegenerative diseases and aging related pathologies; however, the lack of an efficient enrichment method has prevented the analysis of this important low level protein modification. We have developed an efficient method for specific enrichment of nitrotyrosine containing peptides that permits nitrotyrosine peptides and specific nitration sites to be unambiguously identified with LC-MS/MS. The method is based on the derivatization of nitrotyrosine into free sulfhydryl groups followed by high efficiency enrichment of sulfhydryl-containing peptides with thiopropyl sepharose beads. The derivatization process starts with acetylation with acetic anhydride to block all primary amines, followed by reduction of nitrotyrosine to aminotyrosine, then derivatization of aminotyrosine with N-Succinimidyl S-Acetylthioacetate (SATA), and finally deprotecting of S-acetyl on SATA to form free sulfhydryl groups. This method was evaluated using nitrotyrosine containing peptides, in-vitro nitrated human histone 1.2, and bovine serum albumin (BSA). 91% and 62% of the identified peptides from enriched histone and BSA samples were nitrotyrosine derivatized peptides, respectively, suggesting relative high specificity of the enrichment method. The application of this method to in-vitro nitrated mouse brain homogenate resulted in 35% of identified peptides containing nitrotyrosine (compared to only 5.9% observed from the global analysis of unenriched sample), and a total of 150 unique nitrated peptides covering 102 proteins were identified with a false discovery rate estimated at 3.3% from duplicate LC-MS/MS analyses of a single enriched sample.

Zhang, Qibin; Qian, Weijun; Knyushko, Tanya V.; Clauss, Therese RW; Purvine, Samuel O.; Moore, Ronald J.; Sacksteder, Colette A.; Chin, Mark H.; Smith, Desmond J.; Camp, David G.; Bigelow, Diana J.; Smith, Richard D.

2007-06-01

307

Differential Response of High-Elevation Planktonic Bacterial Community Structure and Metabolism to Experimental Nutrient Enrichment  

PubMed Central

Nutrient enrichment of high-elevation freshwater ecosystems by atmospheric deposition is increasing worldwide, and bacteria are a key conduit for the metabolism of organic matter in these oligotrophic environments. We conducted two distinct in situ microcosm experiments in a high-elevation lake (Emerald Lake, Sierra Nevada, California, USA) to evaluate responses in bacterioplankton growth, carbon utilization, and community structure to short-term enrichment by nitrate and phosphate. The first experiment, conducted just following ice-off, employed dark dilution culture to directly assess the impact of nutrients on bacterioplankton growth and consumption of terrigenous dissolved organic matter during snowmelt. The second experiment, conducted in transparent microcosms during autumn overturn, examined how bacterioplankton in unmanipulated microbial communities responded to nutrients concomitant with increasing phytoplankton-derived organic matter. In both experiments, phosphate enrichment (but not nitrate) caused significant increases in bacterioplankton growth, changed particulate organic stoichiometry, and induced shifts in bacterial community composition, including consistent declines in the relative abundance of Actinobacteria. The dark dilution culture showed a significant increase in dissolved organic carbon removal in response to phosphate enrichment. In transparent microcosms nutrient enrichment had no effect on concentrations of chlorophyll, carbon, or the fluorescence characteristics of dissolved organic matter, suggesting that bacterioplankton responses were independent of phytoplankton responses. These results demonstrate that bacterioplankton communities in unproductive high-elevation habitats can rapidly alter their taxonomic composition and metabolism in response to short-term phosphate enrichment. Our results reinforce the key role that phosphorus plays in oligotrophic lake ecosystems, clarify the nature of bacterioplankton nutrient limitation, and emphasize that evaluation of eutrophication in these habitats should incorporate heterotrophic microbial communities and processes.

Nelson, Craig E.; Carlson, Craig A.

2011-01-01

308

Biomineralization of strontianite(SrCO3) by aerobic microorganisms enriched from rhodoliths  

NASA Astrophysics Data System (ADS)

The transport and fate of trace metals and radionuclides in natural environments are controlled by physical, chemical, and microbiological processes. Especially, microbially induced precipitation of carbonates has drawn much attention in recent decades because of its numerous implications such as atmospheric CO2 fixation through mineral carbonation and solid phase capture of inorganic contaminants. The objectives of this study were to investigate the potential for microbially induced precipitation of strontianite (SrCO3) using microorganisms enriched from rhodoliths and to identify mineralogical characteristics of the precipitates of strontianite. Carbonate forming microorganisms were enriched from rhodoliths, which were sampled at Seogwang-ri coast in the western part of Wu Island, Jeju-do, Korea. Microorganisms enriched from rhodoliths were aerobically cultured at 25? in D-1 media containing 30 mM Sr-acetate, and the microorganisms were analyzed by 16S rRNA gene DGGE analysis to confirm microbial diversity. Mineralogical characteristics of the carbonate minerals precipitated by the enriched microorganisms were determined by XRD, TEM-EDS, and SEM-EDS analyses. A 16S rRNA sequence analysis showed the enriched microorganisms contained carbonate forming microorganisms such as Proteus mirailis. The enriched microorganisms precipitated carbonate minerals using D-1 media containing 30 mM Sr-acetate and mineralogy of the precipitate was strontianite (SrCO3). SEM/TEM-EDS analyses showed that the strontianite formed by the microorganisms had a spherical shape and consisted of mainly Sr, O and C. TEM-EDS analyses showed that the strontianite formed by the microorganisms had a rhombohedron shape and consisted of mainly Sr, O and C. These results indicate that the microorganisms induce precipitation of strontianite (SrCO3) on the cell walls and EPS via the accumulation of Sr ions on the cells. Therefore, microbial precipitation of carbonate minerals may play one of important roles in immobilization of metals and radionuclides in natural environments.

Kang, S.; Roh, Y.

2012-12-01

309

Odor Enrichment Sculpts the Abundance of Olfactory Bulb Mitral Cells  

PubMed Central

Mitral cells are the primary output cell from the olfactory bulb conveying olfactory sensory information to higher cortical areas. Gene-targeted deletion of the Shaker potassium channel Kv1.3 alters voltage-dependence and inactivation kinetics of mitral cell current properties, which contribute to the “Super-smeller” phenotype observed in Kv1.3-null mice. The goal of the current study was to determine if morphology and density are influenced by mitral cell excitability, olfactory environment, and stage of development. Wildtype (WT) and Kv1.3-null (KO) mice were exposed to a single odorant (peppermint or citralva) for 30 days. Under unstimulated conditions, postnatal day 20 KO mice had more mitral cells than their WT counterparts, but no difference in cell size. Odor-enrichment with peppermint, an olfactory and trigeminal stimulus, decreased the number of mitral cells in three month and one year old mice of both genotypes. Mitral cell density was most sensitive to odor-stimulation in three month WT mice. Enrichment at the same age with citralva, a purely olfactory stimulus, decreased cell density regardless of genotype. There were no significant changes in cell body shape in response to citralva exposure, but the cell area was greater in WT mice and selectively greater in the ventral region of the OB in KO mice. This suggests that trigeminal or olfactory stimulation may modify mitral cell area and density while not impacting cell body shape. Mitral cell density can therefore be modulated by the voltage and sensory environment to alter information processing or olfactory perception.

Johnson, Melissa Cavallin; Biju, K.C.; Hoffman, Joshua; Fadool, Debra Ann

2013-01-01

310

Odor enrichment sculpts the abundance of olfactory bulb mitral cells.  

PubMed

Mitral cells are the primary output cell from the olfactory bulb conveying olfactory sensory information to higher cortical areas. Gene-targeted deletion of the Shaker potassium channel Kv1.3 alters voltage-dependence and inactivation kinetics of mitral cell current properties, which contribute to the "Super-smeller" phenotype observed in Kv1.3-null mice. The goal of the current study was to determine if morphology and density are influenced by mitral cell excitability, olfactory environment, and stage of development. Wildtype (WT) and Kv1.3-null (KO) mice were exposed to a single odorant (peppermint or citralva) for 30 days. Under unstimulated conditions, postnatal day 20 KO mice had more mitral cells than their WT counterparts, but no difference in cell size. Odor-enrichment with peppermint, an olfactory and trigeminal stimulus, decreased the number of mitral cells in three month and one year old mice of both genotypes. Mitral cell density was most sensitive to odor-stimulation in three month WT mice. Enrichment at the same age with citralva, a purely olfactory stimulus, decreased cell density regardless of genotype. There were no significant changes in cell body shape in response to citralva exposure, but the cell area was greater in WT mice and selectively greater in the ventral region of the OB in KO mice. This suggests that trigeminal or olfactory stimulation may modify mitral cell area and density while not impacting cell body shape. Mitral cell density can therefore be modulated by the voltage and sensory environment to alter information processing or olfactory perception. PMID:23485739

Johnson, Melissa Cavallin; Biju, K C; Hoffman, Joshua; Fadool, Debra Ann

2013-04-29

311

Identification of OBO nonalignments and its implications for OBO enrichment  

PubMed Central

Motivation: Existing projects that focus on the semiautomatic addition of links between existing terms in the Open Biomedical Ontologies can take advantage of reasoners that can make new inferences between terms that are based on the added formal definitions and that reflect nonalignments between the linked terms. However, these projects require that these definitions be necessary and sufficient, a strong requirement that often does not hold. If such definitions cannot be added, the reasoners cannot point to the nonalignments through the suggestion of new inferences. Results: We describe a methodology by which we have identified over 1900 instances of nonredundant nonalignments between terms from the Gene Ontology (GO) biological process (BP), cellular component (CC) and molecular function (MF) ontologies, Chemical Entities of Biological Interest (ChEBI) and the Cell Type Ontology (CL). Many of the 39.8% of these nonalignments whose object terms are more atomic than the subject terms are not currently examined in other ontology-enrichment projects due to the fact that the necessary and sufficient conditions required for the inferences are not currently examined. Analysis of the ratios of nonalignments to assertions from which the nonalignments were identified suggests that BP–MF, BP–BP, BP–CL and CC–CC terms are relatively well-aligned, while ChEBI–MF, BP–ChEBI and CC–MF terms are relatively not aligned well. We propose four ways to resolve an identified nonalignment and recommend an analogous implementation of our methodology in ontology-enrichment tools to identify types of nonalignments that are currently not detected. Availability: The nonalignments discussed in this article may be viewed at http://compbio.uchsc.edu/Hunter_lab/Bada/nonalignments_2008_03_06.html. Code for the generation of these nonalignments is available upon request. Contact: mike.bada@uchsc.edu

Bada, Michael; Hunter, Lawrence

2008-01-01

312

Evaluation of elemental enrichments in surface sediments off southwestern Taiwan  

NASA Astrophysics Data System (ADS)

Surface slices of 20 sediment cores, off southwestern Taiwan, and bed sediment of River Kaoping were measured for major and trace elements (Al, As, Ca, Cd, Cl, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Si, Ti, V, and Zn) to evaluate the geochemical processes responsible for their distribution, including elemental contamination. Major element/Al ratio and mean grain size indicate quartz-dominated, coarse grained sediments that likely derived from sedimentary rocks of Taiwan and upper crust of Yangtze Craton. Bi-plot of SiO2 versus Fe2O{3/T} suggests the possible iron enrichment in sediments of slag dumping sites. Highest concentrations of Cr, Mn, P, S, and Zn found in sediments of dumping sites support this. Correlation analysis shows dual associations, detrital and organic carbon, for Cr, P, S, and V with the latter association typical for sediments in dumping sites. Normalization of trace elements to Al indicates high enrichment factors (>2) for As, Cd, Pb, and Zn, revealing contamination. Factor analysis extracted four geochemical associations with the principal factor accounted for 25.1% of the total variance and identifies the combined effects of dumped iron and steel slag-induced C-S-Fe relationship owing to authigenic precipitation of Fe-Mn oxyhydroxides and/or metal sulfides, and organic matter complexation of Fe, Mn, Ca, Cr, P, and V. Factors 2, 3, and 4 reveal detrital association (Ti, Al, Ni, Pb, Cu, and V), effect of sea salt (Cl, Mg, Na, and K) and anthropogenic component (As and Zn)-carbonate link, respectively, in the investigated sediments.

Chen, Chen-Tung; Kandasamy, Selvaraj

2008-05-01

313

Assessment for Effective Intervention: Enrichment Science Academic Program  

NASA Astrophysics Data System (ADS)

Israel suffers from a growing problem of socio-economic gaps between those who live in the center of the country and residents of outlying areas. As a result, there is a low level of accessibility to higher education among the peripheral population. The goal of the Sidney Warren Science Education Center for Youth at Tel-Hai College is to strengthen the potential of middle and high school students and encourage them to pursue higher education, with an emphasis on majoring in science and technology. This study investigated the implementation and evaluation of the enrichment science academic program, as an example of informal learning environment, with an emphasis on physics studies. About 500 students conducted feedback survey after participating in science activities in four domains: biology, chemistry, physics, and computer science. Results indicated high level of satisfaction among the students. No differences were found with respect to gender excluding in physics with a positive attitudes advantage among boys. In order to get a deeper understanding of this finding, about 70 additional students conducted special questionnaires, both 1 week before the physics enrichment day and at the end of that day. Questionnaires were intended to assess both their attitudes toward physics and their knowledge and conceptions of the physical concept "pressure." We found that the activity moderately improved boys' attitudes toward physics, but that girls displayed decreased interest in and lower self-efficacy toward physics. Research results were used to the improvement of the instructional design of the physics activity demonstrating internal evaluation process for effective intervention.

Sasson, Irit; Cohen, Donita

2012-11-01

314

Continuing Effects of Early Enrichment in Adult Life: The Turkish Early Enrichment Project 22 Years Later  

ERIC Educational Resources Information Center

Long-term studies of early intervention, spanning over decades, are scarce in the United States and nonexistent in the rest of the world. The Turkish Early Enrichment Project (TEEP) is the only non-U.S. example to date. This paper reports a new follow-up assessment of the long-term outcomes of TEEP, an intervention carried out in 1983-1985 with…

Kagitcibasi, Cigdem; Sunar, Diane; Bekman, Sevda; Baydar, Nazli; Cemalcilar, Zeynep

2009-01-01

315

Following isotopes in pulse-chase enriched aspen seedlings  

NASA Astrophysics Data System (ADS)

One method to quantitatively trace biogeochemical fluxes through ecosystems, such as organic matter decomposition, is to use plant material enriched with stable isotopes. However, as plant macromolecules are known to vary in their rate of formation and decomposition, both the enrichment levels and the location of enrichment within the plant material should be characterized prior to decomposition and tracing studies. Aspen (Populus tremuloides Michx.) is a common tree species with a diverse organic matter chemical structure found in the western Canadian boreal forest. This study used a multi pulse and multi chase enrichment of stable isotopes (15N and 13C) on aspen seedlings to determine the seedling enrichment, isotope movement among plant tissues and translocation of isotopes within plant macromolecules e.g., carbohydrates and lignin. As expected, all tissues experienced increased enrichment with multiple pulses. An initial enrichment with 13C was observed in the leaves followed by translocation to the stems and roots while the 15N moved upward from the roots to leaves. The macromolecular chemistry of the organic carbon was further characterized using 13C solid state nuclear magnetic resonance spectroscopy. After the initial two hour chase period enrichment of the O-alkyl type (carbohydrate) carbon within the leaves was identified, followed by redistribution to more complex carbon compounds after the one week chase period. Root and stem tissues did not show the same pattern. Rather, changes in 13C enrichment were observed in shifting ethyl and methyl alkyl (lipid) carbon peak intensities for the stem samples while roots did not preferentially allocate 13C to a specific macromolecule. These results confirm that stable isotope enrichment of plants was non-uniform across macromolecules and tissue types. Enrichment of aspen seedlings was therefore dependant on the pulse-chase sequence used.

Norris, C. E.; Wasylishen, R. E.; Landhäusser, S.; Quideau, S. A.

2011-12-01

316

Enrichment of chemical libraries docked to protein conformational ensembles and application to aldehyde dehydrogenase 2.  

PubMed

Molecular recognition is a complex process that involves a large ensemble of structures of the receptor and ligand. Yet, most structure-based virtual screening is carried out on a single structure typically from X-ray crystallography. Explicit-solvent molecular dynamics (MD) simulations offer an opportunity to sample multiple conformational states of a protein. Here we evaluate our recently developed scoring method SVMSP in its ability to enrich chemical libraries docked to MD structures of seven proteins from the Directory of Useful Decoys (DUD). SVMSP is a target-specific rescoring method that combines machine learning with statistical potentials. We find that enrichment power as measured by the area under the ROC curve (ROC-AUC) is not affected by increasing the number of MD structures. Among individual MD snapshots, many exhibited enrichment that was significantly better than the crystal structure, but no correlation between enrichment and structural deviation from crystal structure was found. We followed an innovative approach by training SVMSP scoring models using MD structures (SVMSPMD). The resulting models were applied to two difficult cases (p38 and CDK2) for which enrichment was not better than random. We found remarkable increase in enrichment power, particularly for p38, where the ROC-AUC increased by 0.30 to 0.85. Finally, we explored approaches for a priori identification of MD snapshots with high enrichment power from an MD simulation in the absence of active compounds. We found that the use of randomly selected compounds docked to the target of interest using SVMSP led to notable enrichment for EGFR and Src MD snapshots. SVMSP rescoring of protein-compound MD structures was applied for the search of small-molecule inhibitors of the mitochondrial enzyme aldehyde dehydrogenase 2 (ALDH2). Rank-ordering of a commercial library of 50?000 compounds docked to MD structures of ALDH2 led to five small-molecule inhibitors. Four compounds had IC50s below 5 ?M. These compounds serve as leads for the design and synthesis of more potent and selective ALDH2 inhibitors. PMID:24856086

Wang, Bo; Buchman, Cameron D; Li, Liwei; Hurley, Thomas D; Meroueh, Samy O

2014-07-28

317

Material control and accounting requirements for uranium enrichment facilities  

Microsoft Academic Search

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

P. Ting; B. W. Moran

1991-01-01

318

Schoolwide Enrichment Model: Challenging All Children to Excel  

ERIC Educational Resources Information Center

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…

Beecher, Margaret

2010-01-01

319

Dance Educator Enrichment Program (DEEP): A Model for Professional Development  

Microsoft Academic Search

In 2001, North Carolina Dance Theatre, The University of North Carolina at Charlotte, and the Charlotte-Mecklenburg School system joined forces to create a multidimensional, professional development program for dance professionals (teachers and artists) in the public schools called, The Dance Educator Enrichment Program (DEEP). DEEP was designed to strengthen and enrich the teaching skills of dance educators while providing additional

Pamela Anderson Sofras; Ambre Emory-Maier

2005-01-01

320

Enrichment and Training Improve Cognition in Rats with Cortical Malformations  

PubMed Central

Children with malformations of cortical development (MCD) frequently have associated cognitive impairments which reduce quality of life. We hypothesized that cognitive deficits associated with MCD can be improved with environmental manipulation or additional training. The E17 methylazoxymethanol acetate (MAM) exposure model bears many anatomical hallmarks seen in human MCDs as well as similar behavioral and cognitive deficits. We divided control and MAM exposed Sprague-Dawley rats into enriched and non-enriched groups and tested performance in the Morris water maze. Another group similarly divided underwent sociability testing and also underwent Magnetic Resonance Imaging (MRI) scans pre and post enrichment. A third group of control and MAM rats without enrichment were trained until they reached criterion on the place avoidance task. MAM rats had impaired performance on spatial tasks and enrichment improved performance of both control and MAM animals. Although MAM rats did not have a deficit in sociability they showed similar improvement with enrichment as controls. MRI revealed a whole brain volume decrease with MAM exposure, and an increase in both MAM and control enriched volumes in comparison to non-enriched animals. In the place avoidance task, MAM rats required approximately 3 times as long to reach criterion as control animals, but with additional training were able to reach control performance. Environmental manipulation and additional training can improve cognition in a rodent MCD model. We therefore suggest that patients with MCD may benefit from appropriate alterations in educational strategies, social interaction and environment. These factors should be considered in therapeutic strategies.

Jenks, Kyle R.; Lucas, Marcella M.; Duffy, Ben A.; Robbins, Ashlee A.; Gimi, Barjor; Barry, Jeremy M.; Scott, Rod C.

2013-01-01

321

Uranium Enrichment Policies and Operations: Status and Future Needs.  

National Technical Information Service (NTIS)

The three Government-owned uranium enrichment plants are the world's primary source of enrichment services. These plants prepare uranium for use as nuclear reactor fuel. The need for, and timing of, future plants depends largely on nuclear power growth, t...

1977-01-01

322

A case study of air enrichment in rotary kiln incineration  

Microsoft Academic Search

This paper presents a case study of air enrichment in an industrial rotary kiln type incineration unit. The study is based on mass and energy balances, considering the combustion reaction of a mixture composed by the residue and the auxiliary fuel with air enriched with oxygen. The steps are shown for the primary chamber (rotary kiln) and secondary chamber (afterburner).

J. A. Carvalho; P. T. Lacava

1998-01-01

323

Enriching Intrusion Alerts Through Multi-Host Causality  

Microsoft Academic Search

Current intrusion detection systems point out suspicious states or events but do not show how the suspicious state or events relate to other states or events in the system. We show how to enrich an IDS alert with information about how those alerts causally lead to or result from other events in the system. By enriching IDS alerts with this

Samuel T. King; Zhuoqing Morley Mao; Dominic G. Lucchetti; Peter M. Chen

2005-01-01

324

A review of environmental enrichment for kennelled dogs, Canis familiaris  

Microsoft Academic Search

Domestic dogs can be housed in a variety of confined conditions, including kennels, shelters and laboratories. Concern over the well-being of dogs housed in human care has prompted much research in recent years into the enrichment of environments for kennelled dogs. This paper highlights the findings and recommendations arising from this work. Two types of general enrichment method are discussed,

Deborah L. Wells

2004-01-01

325

Isolating factors that determine the organic enrichment of sea spray  

Microsoft Academic Search

Particles formed by the bursting of bubbles entrained in ocean waters may become significantly enriched in organic matter relative to sea water particularly for submicron sea spray aerosols formed from ocean waters characterized by high levels of biological activity. However, the factors controlling enrichment are not yet fully understood. The knowledge of marine aerosol chemical composition, as a function of

B. Gantt; E. Morris; M. D. Petters; N. Meskhidze

2010-01-01

326

Jet drop enrichment of bacteria, virus, and dissolved organic material  

Microsoft Academic Search

Four parameters that control the enrichment of bacteria in jet drops are bubble scavenging, drop size, drop position in the jet set, and the type of bacteria. Without the scavenging of bacteria as a bubble rises through the water it is doubtful that the observed enrichment factors, EF, greater than 1000 could be obtained. There is a maximum in EF

Duncan C. Blanchard

1978-01-01

327

Environmental enrichment influences on pig behavior, performance and meat quality  

Microsoft Academic Search

The influence of environmental enrichment and genotype were evaluated for effects on performance, behavior and carcass characteristics in 320 pigs from weaning to slaughter at over 110 kg. Ten treatments were evaluated including two genotypes and five levels of enrichment, arranged factorially. Genotypes were PIC C-15×405 cross (C-15) which is a commonly employed commercial hybrid in the US swine industry

Jeff D. Hill; John J. McGlone; Steven D. Fullwood; Markus F. Miller

1998-01-01

328

21 CFR 139.115 - Enriched macaroni products.  

Code of Federal Regulations, 2010 CFR

...any substance referred to in paragraphs (a) (1), (2), and (3) of this section through the use of dried yeast, dried torula yeast, partly defatted wheat germ, enriched farina, or enriched flour, or through the direct additions of any of the...

2010-04-01

329

21 CFR 139.115 - Enriched macaroni products.  

Code of Federal Regulations, 2010 CFR

...any substance referred to in paragraphs (a) (1), (2), and (3) of this section through the use of dried yeast, dried torula yeast, partly defatted wheat germ, enriched farina, or enriched flour, or through the direct additions of any of the...

2009-04-01

330

Status of reduced enrichment program for research reactors in Japan  

Microsoft Academic Search

The status of reduced enrichment program for research reactors in Japan will be reviewed. The reduced enrichment programs for the JRR-3M, JRR-4 and JMTR of Japan Atomic Energy Agency (JAEA, former name is Japan Atomic Energy Research Institute (JAERI)) has been completed by 1999, and the reactors are being satisfactory operated using LEU fuels. The KUR of Kyoto University Research

Hironobu Unesaki; Kazunori Ohta; Takeshi Inoue

2008-01-01

331

Project Success Enrichment: Language Arts Manual. Short Story Unit.  

ERIC Educational Resources Information Center

This manual is intended for teachers using the Project Success Enrichment (PSE) program to teach language arts to gifted and typical elementary school students. Following an introduction that outlines the purposes and objectives set forth in the Project Success Enrichment: Language Arts Introductory Unit, this component focuses on the short story…

1996

332

Nucleosynthesis in Stars and the Chemical Enrichment of Galaxies  

NASA Astrophysics Data System (ADS)

After the Big Bang, production of heavy elements in the early Universe takes place starting from the formation of the first stars, their evolution, and explosion. The first supernova explosions have strong dynamical, thermal, and chemical feedback on the formation of subsequent stars and evolution of galaxies. However, the nature of the Universe's first stars and supernova explosions has not been well clarified. The signature of the nucleosynthesis yields of the first stars can be seen in the elemental abundance patterns observed in extremely metal-poor stars. Interestingly, those patterns show some peculiarities relative to the solar abundance pattern, which should provide important clues to understanding the nature of early generations of stars. We thus review the recent results of the nucleosynthesis yields of mainly massive stars for a wide range of stellar masses, metallicities, and explosion energies. We also provide yields tables and examine how those yields are affected by some hydrodynamical effects during supernova explosions, namely, explosion energies from those of hypernovae to faint supernovae, mixing and fallback of processed materials, asphericity, etc. Those parameters in the supernova nucleosynthesis models are constrained from observational data of supernovae and metal-poor stars. Nucleosynthesis yields are then applied to the chemical evolution model of our Galaxy and other types of galaxies to discuss how the chemical enrichment process occurred during evolution.

Nomoto, Ken'ichi; Kobayashi, Chiaki; Tominaga, Nozomu

2013-08-01

333

Influence of Enriched Environment on Viral Encephalitis Outcomes: Behavioral and Neuropathological Changes in Albino Swiss Mice  

PubMed Central

An enriched environment has previously been described as enhancing natural killer cell activity of recognizing and killing virally infected cells. However, the effects of environmental enrichment on behavioral changes in relation to virus clearance and the neuropathology of encephalitis have not been studied in detail. We tested the hypothesis that environmental enrichment leads to less CNS neuroinvasion and/or more rapid viral clearance in association with T cells without neuronal damage. Stereology-based estimates of activated microglia perineuronal nets and neurons in CA3 were correlated with behavioral changes in the Piry rhabdovirus model of encephalitis in the albino Swiss mouse. Two-month-old female mice maintained in impoverished (IE) or enriched environments (EE) for 3 months were behaviorally tested. After the tests, an equal volume of Piry virus (IEPy, EEPy)-infected or normal brain homogenates were nasally instilled. Eight days post-instillation (dpi), when behavioral changes became apparent, brains were fixed and processed to detect viral antigens, activated microglia, perineuronal nets, and T lymphocytes by immuno- or histochemical reactions. At 20 or 40 dpi, the remaining animals were behaviorally tested and processed for the same markers. In IEPy mice, burrowing activity decreased and recovered earlier (8–10 dpi) than open field (20–40 dpi) but remained unaltered in the EEPy group. EEPy mice presented higher T-cell infiltration, less CNS cell infection by the virus and/or faster virus clearance, less microgliosis, and less damage to the extracellular matrix than IEPy. In both EEPy and IEPy animals, CA3 neuronal number remained unaltered. The results suggest that an enriched environment promotes a more effective immune response to clear CNS virus and not at the cost of CNS damage.

Bento-Torres, Joao; Trevia, Nonata; de Almeida Lins, Nara Alves; Passos, Aline; Santos, Zaire; Diniz, Jose Antonio Picanco; da Costa Vasconcelos, Pedro Fernando; Cunningham, Colm; Perry, Victor Hugh; Picanco Diniz, Cristovam Wanderley

2011-01-01

334

Conversion of crude oil to methane by a microbial consortium enriched from oil reservoir production waters  

PubMed Central

The methanogenic biodegradation of crude oil is an important process occurring in petroleum reservoirs and other oil-containing environments such as contaminated aquifers. In this process, syntrophic bacteria degrade hydrocarbon substrates to products such as acetate, and/or H2 and CO2 that are then used by methanogens to produce methane in a thermodynamically dependent manner. We enriched a methanogenic crude oil-degrading consortium from production waters sampled from a low temperature heavy oil reservoir. Alkylsuccinates indicative of fumarate addition to C5 and C6 n-alkanes were identified in the culture (above levels found in controls), corresponding to the detection of an alkyl succinate synthase encoding gene (assA/masA) in the culture. In addition, the enrichment culture was tested for its ability to produce methane from residual oil in a sandstone-packed column system simulating a mature field. Methane production rates of up to 5.8 ?mol CH4/g of oil/day were measured in the column system. Amounts of produced methane were in relatively good agreement with hydrocarbon loss showing depletion of more than 50% of saturate and aromatic hydrocarbons. Microbial community analysis revealed that the enrichment culture was dominated by members of the genus Smithella, Methanosaeta, and Methanoculleus. However, a shift in microbial community occurred following incubation of the enrichment in the sandstone columns. Here, Methanobacterium sp. were most abundant, as were bacterial members of the genus Pseudomonas and other known biofilm forming organisms. Our findings show that microorganisms enriched from petroleum reservoir waters can bioconvert crude oil components to methane both planktonically and in sandstone-packed columns as test systems. Further, the results suggest that different organisms may contribute to oil biodegradation within different phases (e.g., planktonic vs. sessile) within a subsurface crude oil reservoir.

Berdugo-Clavijo, Carolina; Gieg, Lisa M.

2014-01-01

335

Photoablative dilution with pre-enrichment for the clonal isolation of rare cancer cells  

NASA Astrophysics Data System (ADS)

The clonal isolation of rare cells, especially cancer and stem cells, in a population is important to cell biology. We have demonstrated that the Laser-Enabled Analysis and Processing (LEAP, Cyntellect Inc., San Diego, CA) instrument can be used to efficiently produce clones by photoablative dilution. The LEAP instrument performs automated fluorescence imaging and real-time image analysis to classify cells. The instrument also features a pulsed laser that gives it the ability to purify a sample by eliminating unwanted cells via laser ablation or UV-induced apoptosis. In photoablative dilution, rare cells are deposited into a multiwell plate at 10 cells per well. Then one cell is chosen to clone, and the other cells present in the well are eliminated by laser ablation. We have successfully used LEAP to produce single cell clones in 95% of wells (originally containing 5+/-2.1 cells/well). While photoablative dilution is a very effective way of producing clonal cultures, it has a fundamental limitation in the low number of cells that can be processed. This can be overcome by performing a pre-enrichment to increase the frequency of the rare cells to be cloned. Another enrichment strategy is flow cytometry based cell sorting. Flow sorting can provide greater than 104 fold enrichment and cells can be sorted directly into a multiwell plate. With pre-enrichment, photoablative dilution can be used to clonally isolate rare cells. This is especially important in cases where the total number of potentially rare cells recovered by first stage enrichment sorting is only 10-200 cells. Such a situation which would normally preclude second pass sorting for purity by the high-throughput first stage cell separation technology.

Zordan, Michael D.; Leary, James F.

2009-02-01

336

Conversion of crude oil to methane by a microbial consortium enriched from oil reservoir production waters.  

PubMed

The methanogenic biodegradation of crude oil is an important process occurring in petroleum reservoirs and other oil-containing environments such as contaminated aquifers. In this process, syntrophic bacteria degrade hydrocarbon substrates to products such as acetate, and/or H2 and CO2 that are then used by methanogens to produce methane in a thermodynamically dependent manner. We enriched a methanogenic crude oil-degrading consortium from production waters sampled from a low temperature heavy oil reservoir. Alkylsuccinates indicative of fumarate addition to C5 and C6 n-alkanes were identified in the culture (above levels found in controls), corresponding to the detection of an alkyl succinate synthase encoding gene (assA/masA) in the culture. In addition, the enrichment culture was tested for its ability to produce methane from residual oil in a sandstone-packed column system simulating a mature field. Methane production rates of up to 5.8 ?mol CH4/g of oil/day were measured in the column system. Amounts of produced methane were in relatively good agreement with hydrocarbon loss showing depletion of more than 50% of saturate and aromatic hydrocarbons. Microbial community analysis revealed that the enrichment culture was dominated by members of the genus Smithella, Methanosaeta, and Methanoculleus. However, a shift in microbial community occurred following incubation of the enrichment in the sandstone columns. Here, Methanobacterium sp. were most abundant, as were bacterial members of the genus Pseudomonas and other known biofilm forming organisms. Our findings show that microorganisms enriched from petroleum reservoir waters can bioconvert crude oil components to methane both planktonically and in sandstone-packed columns as test systems. Further, the results suggest that different organisms may contribute to oil biodegradation within different phases (e.g., planktonic vs. sessile) within a subsurface crude oil reservoir. PMID:24829563

Berdugo-Clavijo, Carolina; Gieg, Lisa M

2014-01-01

337

Oxygen enriched air/natural gas burner system development. Final report, July 1984-September 1989  

SciTech Connect

In order to remain competitive in the global market, energy intensive combustion processes must reduce costs. Air-natural gas combustion is used in many of these processes including heating and melting of glass and metals. These applications are summarized with respect to natural gas consumption and energy efficiency. Oxygen enrichment can increase furnace productivity and reduce operating costs through improved energy efficiency. Commercial air-natural gas burners were shown to be generally limited to 30% enrichment. Since the maximum benefits of oxygen enrichment (high flame temperature and NOx minimization) are achieved with 100% oxygen, a simple retrofit technology was developed to convert air-natural gas burners to fire oxy-fuel. The technology was tested in a ladle preheating process and a glass melting furnace where increased production and fuel savings were observed. In the glass furnace, burner survivability was improved through water cooling. NOx emissions from heating and melting processes have become a significant environmental issue. A computer-based mathematical model was developed to predict the effect of burner firing conditions on NOx levels. The model currently predicts values higher than experimentally observed, but the trend is correct. The data show that conversion of a furnace to 100% oxygen-natural gas can dramatically reduce NOx emissions to well within existing regulations.

Dalton, A.I.; Tyndall, D.W.

1989-11-01

338

Transportable calorimeter measurements of highly enriched uranium  

SciTech Connect

A sensitive calorimeter has been combined with a small temperature-controlled water bath to compose a transportable system that is capable of measuring multikilogram quantities of highly enriched uranium (HEU). The sample chamber size, 5 in. in diameter by 10 in. high, is large enough to hold sufficient HEU metal or high-grade scrap to provide a measurable thermal signal. Calorimetric measurements performed on well-characterized material indicate that the thermal power generated by 93% {sup 235}U samples with 1.0% {sup 234}U can be measured with a precision of about 1% (1 sigma) for 4-kg samples. The transportable system consists of a twin-bridge calorimeter installed inside a 55-gal. stainless steel drum filled with water with heating and cooling supplied by a removable thermoelectric module attached to the side. Isotopic measurements using high-resolution gamma-ray measurements of the HEU samples and analysis with the FRAM code were used to determine the isotopic ratios and specific power of the samples. This information was used to transform the measured thermal power into grams of HEU. Because no physical standards are required, this system could be used for the verification of plutonium, {sup 238}Pu heat sources, or large quantities of metal or other high-grade matrix forms of HEU.

Rudy, C.; Bracken, D.S.; Staples, P.; Carrillo, L.

1997-11-01

339

Early Gaseous Oxygen Enrichment to Enhance Magnetite Pellet Oxidation  

NASA Astrophysics Data System (ADS)

It is suggested that oxygen enrichment in the gas atmosphere, during continuous heating of magnetite pellets, can cause pellets to be oxidized throughout their volumes, eliminating unoxidized cores. The peculiarities of the oxidation kinetics of magnetite concentrate imply that such oxygen enrichment might be particularly effective at lower temperatures. This suggestion was tested by developing and testing a mixed-control model for pellet oxidation (to allow the sizes of unreacted cores to be predicted), and by experimentally testing the effects of oxygen enrichment at relatively low temperatures ("early oxygen enrichment"). The results confirmed that the extents (depth) of oxidation and pellet strength were both improved significantly by applying oxygen enrichment up to 873 K (600 °C), as part of a heating cycle up to 1073 K (800 °C).

Tang, Ming; Cho, Hyeon Jeong; Pistorius, Petrus Christiaan

2014-04-01

340

Plutonium isotopic analysis of highly enriched mixed oxides  

SciTech Connect

We investigated the analysis method used by the International Atomic Energy Agency (IAEA) to determine the plutonium isotopic composition of highly enriched mixed oxides (MOX). The IAEA currently uses the Cicero multichannel analyzer and the IAEAPU algorithm for its analysis. In our investigation the plutonium isotopic measurements were found to be good for PuO/sub 2/ powder or low-enriched MOX, but acceptable for highly enriched MOX in IAEA special nuclear material (SNM) accountability applications. The gamma-ray interferences from /sup 235/U resulted in underestimation of the isotopic composition of /sup 239/Pu and overestimation of all other plutonium isotopes. Samples with high /sup 240/Pu content were found to have significantly higher error in plutonium isotopic analyses of highly enriched MOX. Code modifications or use of calibration curves are necessary for plutonium isotopic analyses of highly enriched MOX in IAEA SNM accountability applications.

Clement, S.D.; Augustson, R.H.

1986-08-01

341

HIGHLY ENRICHED URANIUM BLEND DOWN PROGRAM AT THE SAVANNAH RIVER SITE PRESENT AND FUTURE  

SciTech Connect

The Department of Energy (DOE) and Tennessee Valley Authority (TVA) entered into an Interagency Agreement to transfer approximately 40 metric tons of highly enriched uranium (HEU) to TVA for conversion to fuel for the Browns Ferry Nuclear Power Plant. Savannah River Site (SRS) inventories included a significant amount of this material, which resulted from processing spent fuel and surplus materials. The HEU is blended with natural uranium (NU) to low enriched uranium (LEU) with a 4.95% 235U isotopic content and shipped as solution to the TVA vendor. The HEU Blend Down Project provided the upgrades needed to achieve the product throughput and purity required and provided loading facilities. The first blending to low enriched uranium (LEU) took place in March 2003 with the initial shipment to the TVA vendor in July 2003. The SRS Shipments have continued on a regular schedule without any major issues for the past 5 years and are due to complete in September 2008. The HEU Blend program is now looking to continue its success by dispositioning an additional approximately 21 MTU of HEU material as part of the SRS Enriched Uranium Disposition Project.

Magoulas, V; Charles Goergen, C; Ronald Oprea, R

2008-06-05

342

Preparation of titanium-grafted magnetic mesoporous silica for the enrichment of endogenous serum phosphopeptides.  

PubMed

As one of the most important post-translational modifications, reversible phosphorylation of protein plays crucial roles in a large number of biological processes. Moreover, endogenous phosphopeptides are also associated with certain human diseases. An efficient enrichment and separation method is the premise for successful identification and quantification of phosphopeptides. In this work, titanium grafted magnetic mesoporous silica (Fe3O4@Ti-mSiO2) was developed and applied for the enrichment of endogenous phosphopeptides. Fe3O4@Ti-mSiO2 particles were prepared by grafting titanocene dichloride on the inner walls of magnetic mesoporous silica and then being calcined to remove cyclopentadienyl ligand. The physicochemical properties of the prepared materials were characterized by energy dispersive X-ray spectroscopy (EDX), nitrogen adsorption-desorption analysis, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM). For selective enrichment of phosphopeptides, the prepared Fe3O4@Ti-mSiO2 particles were applied for tryptic digests of ?-casein, mixtures of ?-casein and bovine serum albumin (BSA), and low-fat milk. Finally, Fe3O4@Ti-mSiO2 was successfully applied for the enrichment of endogenous phosphopeptides from human serum. PMID:24090595

Li, Xiao-Shui; Pan, Ya-Ni; Zhao, Yong; Yuan, Bi-Feng; Guo, Lin; Feng, Yu-Qi

2013-11-01

343

Discontinuous pH gradient-mediated separation of TiO2-enriched phosphopeptides  

PubMed Central

Global profiling of phosphoproteomes has proven a great challenge due to the relatively low stoichiometry of protein phosphorylation and poor ionization efficiency in mass spectrometers. Effective, physiologically-relevant, phosphoproteome research relies on the efficient phosphopeptide enrichment from complex samples. Immobilized metal affinity chromatography and titanium dioxide chromatography (TOC) can greatly assist selective phosphopeptide enrichment. However, the complexity of resultant enriched samples is often still high, suggesting that further separation of enriched phosphopeptides is required. We have developed a pH-gradient elution technique for enhanced phosphopeptide identification in conjunction with TOC. Using this process, we have demonstrated its superiority to the traditional ‘one-pot’ strategies for differential protein identification. Our technique generated a highly specific separation of phosphopeptides by an applied pH-gradient between 9.2 and 11.3. The most efficient elution range for high-resolution phosphopeptide separation was between pH 9.2 and 9.4. High-resolution separation of multiply-phosphorylated peptides was primarily achieved using elution ranges > pH 9.4. Investigation of phosphopeptide sequences identified in each pH fraction indicated that phosphopeptides with phosphorylated residues proximal to acidic residues, including glutamic acid, aspartic acid, and other phosphorylated residues, were preferentially eluted at higher pH values.

Park, Sung-Soo; Maudsley, Stuart

2010-01-01

344

Benzoboroxole-functionalized magnetic core/shell microspheres for highly specific enrichment of glycoproteins under physiological conditions.  

PubMed

Efficient enrichment of specific glycoproteins from complex biological samples is of great importance towards the discovery of disease biomarkers in biological systems. Recently, phenylboronic acid-based functional materials have been widely used for enrichment of glycoproteins. However, such enrichment was mainly carried out under alkaline conditions, which is different to the status of glycoproteins in neutral physiological conditions and may cause some unpredictable degradation. In this study, on-demand neutral enrichment of glycoproteins from crude biological samples is accomplished by utilizing the reversible interaction between the cis-diols of glycoproteins and benzoboroxole-functionalized magnetic composite microspheres (Fe3O4/PAA-AOPB). The Fe3O4/PAA-AOPB composite microspheres are deliberately designed and constructed with a high-magnetic-response magnetic supraparticle (MSP) core and a crosslinked poly(acrylic acid) (PAA) shell anchoring abundant benzoboroxole functional groups on the surface. These nanocomposites possessed many merits, such as large enrichment capacity (93.9 mg/g, protein/beads), low non-specific adsorption, quick enrichment process (10 min) and magnetic separation speed (20 s), and high recovery efficiency. Furthermore, the as-prepared Fe3O4/PAA-AOPB microspheres display high selectivity to glycoproteins even in the E. coli lysate or fetal bovine serum, showing great potential in the identify of low-abundance glycoproteins as biomarkers in real complex biological systems for clinical diagnoses. PMID:24307573

Zhang, Yuting; Ma, Wanfu; Li, Dian; Yu, Meng; Guo, Jia; Wang, Changchun

2014-04-01

345

Air-Xe enrichments in Elk Hills oil field gases: role of water in migration and storage  

NASA Astrophysics Data System (ADS)

Hydrocarbons from the Elk Hills Naval Petroleum Reserve (NPR#1), Bakersfield, CA, are enriched in heavy noble gases. The 132Xe/ 36Ar ratios are as high as ˜576 times the ratio in air and represent the largest relative Xe-enrichments ever observed in terrestrial fluids. The Xe isotopic composition is indistinguishable from air. We show that these samples cannot be explained by equilibration of oil with air saturated water and secondary enrichment via a Rayleigh distillation gas stripping process. Based on laboratory studies of others with potential petroleum source rocks, we believe the source of this enriched heavy noble gas component was adsorbed air initially trapped in/on the source rocks that was expelled and mixed with the hydrocarbons during expulsion and primary migration. Kr and Xe enrichments decrease with increasing 36Ar concentration. We propose a model in which an initial Kr-Xe-enriched hydrocarbon becomes diluted with noble gases extracted from air saturated groundwater during expulsion, migration, and storage. The model generates an integrated water/hydrocarbon ratio for the production fluid which indicates a minimal role for water in hydrocarbon expulsion and migration. The results are interpreted to provide time/geometrical constraints on the mechanisms by which hydrocarbons can migrate as a separate phase.

Torgersen, T.; Kennedy, B. M.

1999-04-01

346

Enrichment of By-Product Materials from Steel Pickling Acid Regeneration Plants (TRP 9942)  

SciTech Connect

A new process for manufacturing an enriched, iron-based product (strontium hexaferrite) in existing steel pickling acid regeneration facilities was evaluated. Process enhancements and equipment additions were made to an existing acid regeneration plant to develop and demonstrate (via pilot scale testing and partial-capacity production trials) the viability of a patented method to produce strontium-based compounds that, when mixed with steel pickling acid and roasted, would result in a strontium hexaferrite powder precursor which could then be subjected to further heat treatment in an atmosphere that promotes rapid, relatively low-temperature formation of discrete strontium hexaferrite magnetic domains yielding an enriched iron-based product, strontium hexaferrite, that can be used in manufacturing hard ferrite magnets.

Lu Swan, Delta Ferrites LLC

2009-09-30

347

Establishing Specifications for Low Enriched Uranium Fuel Operations Conducted Outside the High Flux Isotope Reactor Site  

SciTech Connect

The National Nuclear Security Administration (NNSA) has funded staff at Oak Ridge National Laboratory (ORNL) to study the conversion of the High Flux Isotope Reactor (HFIR) from the current, high enriched uranium fuel to low enriched uranium fuel. The LEU fuel form is a metal alloy that has never been used in HFIR or any HFIR-like reactor. This report provides documentation of a process for the creation of a fuel specification that will meet all applicable regulations and guidelines to which UT-Battelle, LLC (UTB) the operating contractor for ORNL - must adhere. This process will allow UTB to purchase LEU fuel for HFIR and be assured of the quality of the fuel being procured.

Pinkston, Daniel [ORNL; Primm, Trent [ORNL; Renfro, David G [ORNL; Sease, John D [ORNL

2010-10-01

348

Herbivore responses to nutrient enrichment and landscape heterogeneity in a mangrove ecosystem  

Microsoft Academic Search

Complex gradients in forest structure across the landscape of offshore mangrove islands in Belize are associated with nutrient\\u000a deficiency and flooding. While nutrient availability can affect many ecological processes, here we investigate how N and P\\u000a enrichment interact with forest structure in three distinct zones (fringe, transition, dwarf) to alter patterns of herbivory\\u000a as a function of folivory, loss of

Ilka C. Feller; Anne Chamberlain

2007-01-01

349

Soil respiration under mature deciduous forest trees after 7 years of CO2 enrichment  

Microsoft Academic Search

The anthropogenic rise in atmospheric CO2 is expected to impact carbon fluxes not only at ecosystem level but also at the global scale by altering carbon cycle processes in soils. At the Swiss Canopy Crane (SCC), we examined how 7 years of free air CO2 enrichment (FACE) affected soil CO2 dynamics in a c. 100-year-old mixed deciduous forest. The use

Martin Bader; Christian Körner

2010-01-01

350

A novel dual-layer forward osmosis membrane for protein enrichment and concentration  

Microsoft Academic Search

We have demonstrated the prospect of dual-layer polybenzimidazole-polyethersulfone\\/polyvinylpyrrolidone (PBI–PES\\/PVP) hollow fiber nanofiltration (NF) membranes in the forward osmosis (FO) process for the enrichment and concentration of pharmaceutical products without denaturing the component of interests. The dual-layer hollow fiber membrane via coextrusion technology has an ultra-thin selective skin around 10?m, fully open-cell water channels underneath and a microporous sponge-like support structure.

Qian Yang; Kai Yu Wang; Tai-Shung Chung

2009-01-01

351

Environmental Enrichment for Primates: Annotated Database on Environmental Enrichment and Refinement of Husbandry for Nonhuman Primates  

NSDL National Science Digital Library

The Animal Welfare Institute, a nonprofit organization founded "to reduce the sum total of pain and fear inflicted on animals by humans," offers this frequently updated bibliographic database for information on all aspects of environmental enrichment for nonhuman primates. Search results include a list of relevant references with complete bibliographic information, brief summaries of each entry, Web links to full-text documents where available, and a keyword index for easily finding related sources. Users may also browse the entire contents of the database alphabetically. Primatologists and animal handlers alike should find this comprehensive database particularly useful.

2008-08-29

352

Environmental Enrichment for Primates: Annotated Database on Environmental Enrichment and Refinement of Husbandry for Nonhuman Primates  

NSDL National Science Digital Library

The Animal Welfare Institute, a nonprofit organization founded "to reduce the sum total of pain and fear inflicted on animals by humans," offers this frequently updated bibliographic database for information on all aspects of environmental enrichment for nonhuman primates. Search results include a list of relevant references with complete bibliographic information, brief summaries of each entry, Web links to full-text documents where available, and a keyword index for easily finding related sources. Users may also browse the entire contents of the database alphabetically. Primatologists and animal handlers alike should find this comprehensive database particularly useful.

1998-01-01

353

Anammox enrichment from different conventional sludges.  

PubMed

Three sets of sequencing batch reactor (SBR) were used for Anammox enrichment from conventional sludges including upflow anaerobic sludge blanket, activated sludge, and anaerobic digestion sludge. After four months of operation, the Anammox activity occurred in all reactors allowing continuous removal of ammonium and nitrite. The morphology of the cultivated Anammox sludge was observed using scanning electron microscope. The photographs showed that the obtained culture was mostly spherical in shape, presumably Anammox culture. There were also filamentous-like bacteria co-existing in the system. Fluorescence in situ hybridization (FISH) analysis using 16S rRNA targeting oligonucleotide probes PLA46 and Amx820 showed that the dominant population developed in all SBRs was hybridized with both PLA46 and Amx820 gene probes. It means that the cultivated biomass in all SBRs was classified in the group of Planctomycetales bacteria with respect to the anaerobic ammonium-oxidizing bacteria, Candidatus Brocadia anammoxidans and Candidatus Kuenenia stuttgartiensis. Numerous time sequences were tested in this experiment. The shortest workable reaction time was found in the range from 5 to 7 h. Good quiescence of sludge was obtained at 30 min of settle period followed by a discharge period of 15 min. A long-term performance showed a near perfect removal of nitrite based on the influent NO2(-)-N concentration of 50-70 mg l(-1). The maximum ammonia removal efficiency was 80% with the influent NH4(+)-N concentration of 40-60 mg l(-1). It is, therefore, concluded that Anammox cultivation from conventional sludges was highly possible under control environment within four months. PMID:17207839

Chamchoi, Nutchanat; Nitisoravut, Suwanchai

2007-02-01

354

Immunomagnetic separation can enrich fixed solid tumors for epithelial cells.  

PubMed Central

Immunomagnetic separation is a highly specific technique for the enrichment or isolation of cells from a variety of fresh tissues and microorganisms or molecules from suspensions. Because new techniques for molecular analysis of solid tumors are now applicable to fixed tissue but sometimes require or benefit from enrichment for tumor cells, we tested the efficacy of immunomagnetic separation for enriching fixed solid tumors for malignant epithelial cells. We applied it to two different tumors and fixation methods to separate neoplastic from non-neoplastic cells in primary colorectal cancers and metastatic breast cancers, and were able to enrich to a high degree of purity. Immunomagnetic separation was effective in unembedded fixed tissue as well as fixed paraffin-embedded tissue. The magnetically separated cells were amenable to fluorescence in situ hybridization and polymerase chain reaction amplification of their DNA with minimal additional manipulation. The high degree of enrichment achieved before amplification contributed to interpretation of loss of heterozygosity in metastatic breast cancers, and simplified fluorescence in situ hybridization analysis because only neoplastic cells were hybridized and counted. Immunomagnetic separation is effective for the enrichment of fixed solid tumors, can be performed with widely available commercial antibodies, and requires little specialized instrumentation. It can contribute to interpretation of results in situations where enrichment by other methods is difficult or not possible. Images Figure 1 Figure 2 Figure 3

Yaremko, M. L.; Kelemen, P. R.; Kutza, C.; Barker, D.; Westbrook, C. A.

1996-01-01

355

Salt Enrichment of Municipal Sewage: New Prevention Approaches in Israel  

PubMed

Wastewater irrigation is an environmentally sound wastewater disposal practice, but sewage is more saline than the supplied fresh water and the salts are recycled together with the water. Salts have negative environmental effects on crops, soils, and groundwater. There are no inexpensive ways to remove the salts once they enter sewage, and the prevention of sewage salt enrichment is the most immediately available solution. The body of initiatives presently structured by the Ministry of the Environment of Israel are herein described, with the aim to contribute to the search for a long-term solution of salinity problems in arid countries. The new initiatives are based on: (1) search for new technologies to reduce salt consumption and discharge into sewage; (2) different technologies to cope with different situations; (3) raising the awareness of the public and industry on the environmental implications of salinity pollution; and (4) an elastic legal approach expressed through new state-of-the-art regulations. The main contributor to the salinity of sewage in Israel is the water-softening process followed by the meat koshering process. Some of the adopted technical solutions are: the discharge of the brine into the sea, the substitution of sodium by potassium salts in the ion-exchangers, the construction of centralized systems for the supply of soft water in industrial areas, the precipitation of Ca and Mg in the effluents from ion-exchangers and recycling of the NaCl solution, a reduction of the discharge of salts by the meat koshering process, and new membrane technology for salt recovery. PMID:8661617

Weber; Avnimelech; Juanico

1996-07-01

356

Salt enrichment of municipal sewage: New prevention approaches in Israel  

NASA Astrophysics Data System (ADS)

Wastewater irrigation is an environmentally sound wastewater disposal practice, but sewage is more saline than the supplied fresh water and the salts are recycled together with the water. Salts have negative environmental effects on crops, soils, and groundwater. There are no inexpensive ways to remove the salts once they enter sewage, and the prevention of sewage salt enrichment is the most immediately available solution. The body of initiatives presently structured by the Ministry of the Environment of Israel are herein described, with the aim to contribute to the search for a long-term solution of salinity problems in arid countries. The new initiatives are based on: (1) search for new technologies to reduce salt consumption and discharge into sewage; (2) different technologies to cope with different situations; (3) raising the awareness of the public and industry on the environmental implications of salinity pollution; and (4) an elastic legal approach expressed through new state-of-the-art regulations. The main contributor to the salinity of sewage in Israel is the watersoftening process followed by the meat koshering process. Some of the adopted technical solutions are: the discharge of the brine into the sea, the substitution of sodium by potassium salts in the ion-exchangers, the construction of centralized systems for the supply of soft water in industrial areas, the precipitation of Ca and Mg in the effluents from ion-exchangers and recycling of the NaCI solution, a reduction of the discharge of salts by the meat koshering process, and new membrane technology for salt recovery.

Weber, Baruch; Avnimelech, Yoram; Juanico, Marcelo

1996-07-01

357

From sets to graphs: towards a realistic enrichment analysis of transcriptomic systems  

PubMed Central

Motivation: Current gene set enrichment approaches do not take interactions and associations between set members into account. Mutual activation and inhibition causing positive and negative correlation among set members are thus neglected. As a consequence, inconsistent regulations and contextless expression changes are reported and, thus, the biological interpretation of the result is impeded. Results: We analyzed established gene set enrichment methods and their result sets in a large-scale investigation of 1000 expression datasets. The reported statistically significant gene sets exhibit only average consistency between the observed patterns of differential expression and known regulatory interactions. We present Gene Graph Enrichment Analysis (GGEA) to detect consistently and coherently enriched gene sets, based on prior knowledge derived from directed gene regulatory networks. Firstly, GGEA improves the concordance of pairwise regulation with individual expression changes in respective pairs of regulating and regulated genes, compared with set enrichment methods. Secondly, GGEA yields result sets where a large fraction of relevant expression changes can be explained by nearby regulators, such as transcription factors, again improving on set-based methods. Thirdly, we demonstrate in additional case studies that GGEA can be applied to human regulatory pathways, where it sensitively detects very specific regulation processes, which are altered in tumors of the central nervous system. GGEA significantly increases the detection of gene sets where measured positively or negatively correlated expression patterns coincide with directed inducing or repressing relationships, thus facilitating further interpretation of gene expression data. Availability: The method and accompanying visualization capabilities have been bundled into an R package and tied to a grahical user interface, the Galaxy workflow environment, that is running as a web server. Contact: Ludwig.Geistlinger@bio.ifi.lmu.de; Ralf.Zimmer@bio.ifi.lmu.de

Geistlinger, Ludwig; Csaba, Gergely; Kuffner, Robert; Mulder, Nicola; Zimmer, Ralf

2011-01-01

358

Biodegradation of haloacetic acids by bacterial isolates and enrichment cultures from drinking water systems.  

PubMed

Biodegradation is a potentially important loss process for haloacetic acids (HAAs), a class of chlorination byproducts, in water treatment and distribution systems, but little is known about the organisms involved (i.e., identity, substrate range, biodegradation kinetics). In this research, 10 biomass samples (i.e., tap water, distribution system biofilms, and prechlorinated granular activated carbon filters) from nine drinking water systems were used to inoculate a total of thirty enrichment cultures fed monochloroacetic acid (MCAA), dichloroacetic acid (DCAA), or trichloroacetic (TCAA) as sole carbon and energy source. HAA degraders were successfully enriched from the biofilm samples (GAC and distribution system) but rarely from tap water. Half of the MCAA and DCAA enrichment cultures were positive, whereas only one TCAA culture was positive (two were inconclusive). Eight unique HAA-degrading isolates were obtained including several Afipia spp. and a Methylobacterium sp.; all isolates were members of the phylum Proteobacteria. MCAA, monobromoacetic acid (MBAA), and monoiodoacetic acid (MIAA) were rapidly degraded by all isolates, and DCAA and tribromoacetic (TBAA) were also relatively labile. TCAA and dibromoacetic acid (DBAA)were degraded by only three isolates and degradation lagged behind the other HAAs. Detailed DCAA biodegradation kinetics were obtained for two selected isolates and two enrichment cultures. The maximum biomass-normalized degradation rates (Vm) were 0.27 and 0.97 microg DCAA/ microg protein/h for Methylobacterium fujisawaense strain PAWDI and Afipia felis strain EMD2, respectively, which were comparable to the values obtained for the enrichment cultures from which those organisms were isolated (0.39 and 1.37 microg DCAN/microg protein/h, respectively). The half-saturation constant (Km) values ranged from 4.38 to 77.91 microg DCAA/L and the cell yields ranged from 14.4 to 36.1 mg protein/g DCAA. PMID:19534130

Zhang, Ping; Lapara, Timothy M; Goslan, Emma H; Xie, Yuefeng; Parsons, Simon A; Hozalski, Raymond M

2009-05-01

359

Robust phosphoproteome enrichment using monodisperse microsphere-based immobilized titanium (IV) ion affinity chromatography.  

PubMed

Mass spectrometry (MS)-based proteomics has become the preferred tool for the analysis of protein phosphorylation. To be successful at such an endeavor, there is a requirement for an efficient enrichment of phosphopeptides. This is necessary because of the substoichiometric nature of phosphorylation at a given site and the complexity of the cell. Recently, new alternative materials have emerged that allow excellent and robust enrichment of phosphopeptides. These monodisperse microsphere-based immobilized metal ion affinity chromatography (IMAC) resins incorporate a flexible linker terminated with phosphonate groups that chelate either zirconium or titanium ions. The chelated zirconium or titanium ions bind specifically to phosphopeptides, with an affinity that is similar to that of other widely used metal oxide affinity chromatography materials (typically TiO(2)). Here we present a detailed protocol for the preparation of monodisperse microsphere-based Ti(4+)-IMAC adsorbents and the subsequent enrichment process. Furthermore, we discuss general pitfalls and crucial steps in the preparation of phosphoproteomics samples before enrichment and, just as importantly, in the subsequent mass spectrometric analysis. Key points such as lysis, preparation of the chromatographic system for analysis and the most appropriate methods for sequencing phosphopeptides are discussed. Bioinformatics analysis specifically relating to site localization is also addressed. Finally, we demonstrate how the protocols provided are appropriate for both single-protein analysis and the screening of entire phosphoproteomes. It takes ?2 weeks to complete the protocol: 1 week to prepare the Ti(4+)-IMAC material, 2 d for sample preparation, 3 d for MS analysis of the enriched sample and 2 d for data analysis. PMID:23391890

Zhou, Houjiang; Ye, Mingliang; Dong, Jing; Corradini, Eleonora; Cristobal, Alba; Heck, Albert J R; Zou, Hanfa; Mohammed, Shabaz

2013-03-01

360

Network enrichment analysis: extension of gene-set enrichment analysis to gene networks  

PubMed Central

Background Gene-set enrichment analyses (GEA or GSEA) are commonly used for biological characterization of an experimental gene-set. This is done by finding known functional categories, such as pathways or Gene Ontology terms, that are over-represented in the experimental set; the assessment is based on an overlap statistic. Rich biological information in terms of gene interaction network is now widely available, but this topological information is not used by GEA, so there is a need for methods that exploit this type of information in high-throughput data analysis. Results We developed a method of network enrichment analysis (NEA) that extends the overlap statistic in GEA to network links between genes in the experimental set and those in the functional categories. For the crucial step in statistical inference, we developed a fast network randomization algorithm in order to obtain the distribution of any network statistic under the null hypothesis of no association between an experimental gene-set and a functional category. We illustrate the NEA method using gene and protein expression data from a lung cancer study. Conclusions The results indicate that the NEA method is more powerful than the traditional GEA, primarily because the relationships between gene sets were more strongly captured by network connectivity rather than by simple overlaps.

2012-01-01

361

Realities of verifying the absence of highly enriched uranium (HEU) in gas centrifuge enrichment plants  

SciTech Connect

Over a two and one-half year period beginning in 1981, representatives of six countries (United States, United Kingdom, Federal Republic of Germany, Australia, The Netherlands, and Japan) and the inspectorate organizations of the International Atomic Energy Agency and EURATOM developed and agreed to a technically sound approach for verifying the absence of highly enriched uranium (HEU) in gas centrifuge enrichment plants. This effort, known as the Hexapartite Safeguards Project (HSP), led to the first international concensus on techniques and requirements for effective verification of the absence of weapons-grade nuclear materials production. Since that agreement, research and development has continued on the radiation detection technology-based technique that technically confirms the HSP goal is achievable. However, the realities of achieving the HSP goal of effective technical verification have not yet been fully attained. Issues such as design and operating conditions unique to each gas centrifuge plant, concern about the potential for sensitive technology disclosures, and on-site support requirements have hindered full implementation and operator support of the HSP agreement. In future arms control treaties that may limit or monitor fissile material production, the negotiators must recognize and account for the realities and practicalities in verifying the absence of HEU production. This paper will describe the experiences and realities of trying to achieve the goal of developing and implementing an effective approach for verifying the absence of HEU production. 3 figs.

Swindle, D.W.

1990-03-01

362

Enrichment Medium for Selection of Salmonella from Fish Homogenate1  

PubMed Central

A new liquid medium, called “dulcitol selenite enrichment,” has been developed for the detection and enumeration of Salmonella in foods. The medium is not only highly selective in enriching Salmonella and inhibiting completely or appreciably other extraneous organisms commonly found in seafoods, but is also highly sensitive in recovering as low as 2 to 7 cells of Salmonella, even in the presence of large numbers (104 to 106 cells) of mixed flora common to these foods. The addition of seafood material does not seem to interfere with the sensitivity, selectivity, or productivity of the medium. Even physiologically debilitated cells of Salmonella were enriched well enough in this medium to be detected easily.

Raj, H.

1966-01-01

363

Consuming iodine enriched eggs to solve the iodine deficiency endemic for remote areas in Thailand  

PubMed Central

Background Evidence showed that the occurrence of iodine deficiency endemic areas has been found in every provinces of Thailand. Thus, a new pilot programme for elimination of iodine deficiency endemic areas at the community level was designed in 2008 by integrating the concept of Sufficient Economic life style with the iodine biofortification of nutrients for community consumption. Methods A model of community hen egg farm was selected at an iodine deficiency endemic area in North Eastern part of Thailand. The process for the preparation of high content iodine enriched hen food was demonstrated to the farm owner with technical transfer in order to ensure the sustainability in the long term for the community. The iodine content of the produced iodine enriched hen eggs were determined and the iodine status of volunteers who consumed the iodine enriched hen eggs were monitored by using urine iodine excretion before and after the implement of iodine enrichment in the model farm. Results The content of iodine in eggs from the model farm were 93.57 ?g per egg for the weight of 55 - 60 g egg and 97.76 ?g for the weight of 60 - 65 g egg. The biological active iodo-organic compounds in eggs were tested by determination of the base-line urine iodine of the volunteer villagers before and after consuming a hard boiled iodine enriched egg per volunteer at breakfast for five days continuous period in 59 volunteers of Ban Kew village, and 65 volunteers of Ban Nong Nok Kean village. The median base-line urine iodine level of the volunteers in these two villages before consuming eggs were 7.00 and 7.04 ?g/dL respectively. After consuming iodine enriched eggs, the median urine iodine were raised to the optimal level at 20.76 ?g/dL for Ban Kew and 13.95 ?g/dL for Ban Nong Nok Kean. Conclusions The strategic programme for iodine enrichment in the food chain with biological iodo-organic compound from animal origins can be an alternative method to fortify iodine in the diet for Iodine Deficiency Endemic Areas at the community level in Thailand.

2010-01-01

364

Thermal infrared emission spectroscopy of titanium-enriched pyroxenes  

NASA Astrophysics Data System (ADS)

Pyroxenes are useful indicators of igneous processes and may be identified in geologic materials in the laboratory or remotely through the use of spectroscopic analysis. Studies of the thermal infrared (vibrational) spectra of many compositions in the pyroxene solid solution series (quadrilateral orthopyroxene and clinopyroxene, and some nonquadrilateral compositions) have shown that spectral absorption features shift in wavelength position, vary in number, and change shape as a function of pyroxene silicate structure and cation substitution. These spectral variations can be used to identify the approximate composition(s) of pyroxenes in the thermal infrared emission spectra of rocks. Here I demonstrate that the spectra of Ti-rich calcic clinopyroxenes also have thermal infrared spectral characteristics that distinguish them from typical quadrilateral compositions via a comparison to the spectrum of Angra dos Reis, a meteorite dominated by Ti-enriched clinopyroxene. The distinctive spectral character of Ti-rich pyroxenes may permit their identification not only in laboratory mineral and rock samples but also in thermal infrared remote sensing data, providing additional chemical information about igneous lithologies.

Hamilton, V. E.

2003-08-01

365

Enrichment by supernovae in globular clusters with multiple populations.  

PubMed

The most massive globular cluster in the Milky Way, omega Centauri, is thought to be the remaining core of a disrupted dwarf galaxy, as expected within the model of hierarchical merging. It contains several stellar populations having different heavy elemental abundances supplied by supernovae-a process known as metal enrichment. Although M 22 appears to be similar to omega Cen, other peculiar globular clusters do not. Therefore omega Cen and M 22 are viewed as exceptional, and the presence of chemical inhomogeneities in other clusters is seen as 'pollution' from the intermediate-mass asymptotic-giant-branch stars expected in normal globular clusters. Here we report Ca abundances for seven globular clusters and compare them to omega Cen. Calcium and other heavy elements can only be supplied through numerous supernovae explosions of massive stars in these stellar systems, but the gravitational potentials of the present-day clusters cannot preserve most of the ejecta from such explosions. We conclude that these globular clusters, like omega Cen, are most probably the relics of more massive primeval dwarf galaxies that merged and disrupted to form the proto-Galaxy. PMID:19940919

Lee, Jae-Woo; Kang, Young-Woon; Lee, Jina; Lee, Young-Wook

2009-11-26

366

Cryopreservation of adult bovine testicular tissue for spermatogonia enrichment.  

PubMed

To develop a procedure for cryopreservation of adult bovine testis tissue, the effects of dimethyl sulphoxide (DMSO), propylene glycol (PG), ethylene glycol (EG), and their concentrations (v/v), as well as different thawing temperatures, on the cell viability of bovine testis tissue after freezing/thawing were examined. The highest testicular cell viabilities came from the media containing DMSO (85.3 ± 1.2 percent), PG (82 ± 1.0 percent) and EG (83.4 ± 1.0 percent) at 10 percent concentration respectively. Using 10 percent DMSO gave significantly higher spermatogonia percentage (61.1 ± 1.2 percent, P < 0.001) than processing with 10 percent PG (54.3 ± 0.6 percent) or 10 percent EG (55 ± 1.8 percent) after differential plating. Thawing in water bath of 37 or 97-100 degree C also provided significantly higher viabilities (85.1 ± 1.0, 85 ± 1.0 percent, P < 0.01, respectively) and spermatogonia percentages (56.6 ± 2.0, 56.6 ± 2.6 percent, P < 0.01, respectively) than that thawing at 4C (23.4 ± 0.8 percent for total viability, 8.97 ± 1.0 percent for spermatogonia percentage). Collectively, 10 percent DMSO and thawing in 37-100 degree C water baths were appropriate for the cryopreservation of bovine testicular tissue and subsequent spermatogonia enrichment. PMID:22020462

Wu, J J; Hu, T J; Guo, B; Yue, Z P; Yang, Z T; Zhang, X M

2011-01-01

367

Low-enriched uranium holdup measurements in Kazakhstan  

SciTech Connect

Quantification of the residual nuclear material remaining in process equipment has long been a challenge to those who work with nuclear material accounting systems. Fortunately, nuclear material has spontaneous radiation emissions that can be measured. If gamma-ray measurements can be made, it is easy to determine what isotope a deposit contains. Unfortunately, it can be quite difficult to relate this measured signal to an estimate of the mass of the nuclear deposit. Typically, the measurement expert must work with incomplete or inadequate information to determine a quantitative result. Simplified analysis models, the distribution of the nuclear material, any intervening attenuation, background(s), and the source-to-detector distance(s) can have significant impacts on the quantitative result. This presentation discusses the application of a generalized-geometry holdup model to the low-enriched uranium fuel pellet fabrication plant in Ust-Kamenogorsk, Kazakhstan. Preliminary results will be presented. Software tools have been developed to assist the facility operators in performing and documenting the measurements. Operator feedback has been used to improve the user interfaces.

Barham, M.A.; Ceo, R.N.; Smith, S.E. [Oak Ridge Y-12 Plant, TN (United States)] [and others

1998-12-31

368

Dual KS: Defining Gene Sets with Tissue Set Enrichment Analysis  

PubMed Central

Background: Gene set enrichment analysis (GSEA) is an analytic approach which simultaneously reduces the dimensionality of microarray data and enables ready inference of the biological meaning of observed gene expression patterns. Here we invert the GSEA process to identify class-specific gene signatures. Because our approach uses the Kolmogorov-Smirnov approach both to define class specific signatures and to classify samples using those signatures, we have termed this methodology “Dual-KS” (DKS). Results: The optimum gene signature identified by the DKS algorithm was smaller than other methods to which it was compared in 5 out of 10 datasets. The estimated error rate of DKS using the optimum gene signature was smaller than the estimated error rate of the random forest method in 4 out of the 10 datasets, and was equivalent in two additional datasets. DKS performance relative to other benchmarked algorithms was similar to its performance relative to random forests. Conclusions: DKS is an efficient analytic methodology that can identify highly parsimonious gene signatures useful for classification in the context of microarray studies. The algorithm is available as the dualKS package for R as part of the bioconductor project.

Yang, Yarong; Kort, Eric J.; Ebrahimi, Nader; Zhang, Zhongfa; Teh, Bin T.

2010-01-01

369

Nanoscience and Nanotechnology Concepts for Enriching High School Curricula  

NASA Astrophysics Data System (ADS)

High school science teachers seeking to enhance student enthusiasm for science and to enrich their curricula with ``real world'' examples might be interested in drawing on nanoscience, which is currently a major branch of study in biology, chemistry, and physics---key high school curriculum areas---and is also a subject much reported upon by the news media. However, presenting nanoscience and nanotechnology in the classroom presents key challenges: the subject matter must be successfully integrated into the core curriculum so as to enhance the students' educational experience; it must support the aims of Texas Essential Knowledge and Skills for Science (TEKC), or equivalent systems in other states; it must be made accessible to students; and it must be presentable with the use of equipment or supplies that are neither too expensive nor too rare to be obtainable by school districts. These last two requirements are particularly difficult, because it is the nature of nanoscale research that complex fabrication processes and expensive characterization methods are typically required. This talk will discuss the authors' experience leading a teachers' workshop session in 2009 to address the issue of introducing nanoscience into the high school science classroom. The workshop is funded by the NSF through the UT-IGERT program, and brings together teachers from across Texas annually for discussion, curriculum-building, and training in concepts related to nanoscience and nanotechnology.

Sanders, Charlotte; Marshall, Jill

2010-03-01

370

Extracting semantically enriched events from biomedical literature  

PubMed Central

Background Research into event-based text mining from the biomedical literature has been growing in popularity to facilitate the development of advanced biomedical text mining systems. Such technology permits advanced search, which goes beyond document or sentence-based retrieval. However, existing event-based systems typically ignore additional information within the textual context of events that can determine, amongst other things, whether an event represents a fact, hypothesis, experimental result or analysis of results, whether it describes new or previously reported knowledge, and whether it is speculated or negated. We refer to such contextual information as meta-knowledge. The automatic recognition of such information can permit the training of systems allowing finer-grained searching of events according to the meta-knowledge that is associated with them. Results Based on a corpus of 1,000 MEDLINE abstracts, fully manually annotated with both events and associated meta-knowledge, we have constructed a machine learning-based system that automatically assigns meta-knowledge information to events. This system has been integrated into EventMine, a state-of-the-art event extraction system, in order to create a more advanced system (EventMine-MK) that not only extracts events from text automatically, but also assigns five different types of meta-knowledge to these events. The meta-knowledge assignment module of EventMine-MK performs with macro-averaged F-scores in the range of 57-87% on the BioNLP’09 Shared Task corpus. EventMine-MK has been evaluated on the BioNLP’09 Shared Task subtask of detecting negated and speculated events. Our results show that EventMine-MK can outperform other state-of-the-art systems that participated in this task. Conclusions We have constructed the first practical system that extracts both events and associated, detailed meta-knowledge information from biomedical literature. The automatically assigned meta-knowledge information can be used to refine search systems, in order to provide an extra search layer beyond entities and assertions, dealing with phenomena such as rhetorical intent, speculations, contradictions and negations. This finer grained search functionality can assist in several important tasks, e.g., database curation (by locating new experimental knowledge) and pathway enrichment (by providing information for inference). To allow easy integration into text mining systems, EventMine-MK is provided as a UIMA component that can be used in the interoperable text mining infrastructure, U-Compare.

2012-01-01

371

Free Air CO2 Enrichment (FACE) Data Management System  

DOE Data Explorer

The U.S. Department of Energy (DOE) has funded trace gas enrichment experiments since the mid 1990s in two separate programs, the Terrestrial Carbon Processes Program and the Program for Ecosystem Research. The experiments are categorized as Free-Air Carbon Dioxide Enrichment (FACE) experiments or open-top chamber (OTC) experiments. DOE initially funded the FACE sites as research and development experiments which later evolved into environmental research user facilities. FACE technology is capable of providing a means by which the environment around growing plants may be modified to realistically simulate future concentrations of atmospheric carbon dioxide (CO2). Unlike the OTC experiments, no containment is required with FACE designs. Previously difficult-to-study natural conditions such as temperature, precipitation, pollination, wind, humidity, and sunlight are now possible. In addition, there are, in theory, no plant size or growth problems caused by the constraint of enclosures (although the system must be sized, or expandable, to accommodate the anticipated future size of the plants during the lifetime of the experiment). Therefore, long-term studies may be conducted. FACE field data represent plant and ecosystem responses to concentrations of atmospheric CO2 in a natural setting possible during the next century. The DOE Biological and Environmental Research Program (BER) is responsible for four "core" FACE sites and projects. These are known as Aspen FACE, Duke FACE, ORNL FACE, and Nevada Deseret FACE. Brookhaven provides operational support to some of these sites, while The FACE Data Management System at ORNL and CDIAC serves as a data repository. In addition, DOE supports OTC experiments in conjunction with the Smithsonian Environmental Research Center (SERC) in Maryland and Florida. There are also FACE experiments ongoing in other countries. [Quoted from the home page of the FACE Data Management System and other pages within the web site.] The FACE Data Management System at ORNL provides links to all the FACE and SERC sites and to the data (both the data archived at CDIAC and data still residing on site-specific pages). Users are also given in-depth information on the concept, provided with a full, linked list of international projects, and guided to related research. The FACE projects were part of the CO2 research network fostered by the Global Change and Terrestrial Ecosystems core project of the International Geosphere-Biosphere Programme. Results from the experiment contribute to the Terrestrial Ecosystem Response to Atmospheric and Climatic Change (TERACC) project, a 5-year initiative integrating experimental data and global change modeling.

372

Chemical enrichment and physical conditions in I Zw 18  

NASA Astrophysics Data System (ADS)

Context. Low-metallicity star-forming dwarf galaxies are prime targets to understand the chemical enrichment of the interstellar medium. The H i region contains the bulk of the mass in blue compact dwarfs, and it provides important constraints on the dispersal and mixing of heavy elements released by successive star-formation episodes. The metallicity of the H i region is also a critical parameter to investigate the future star-formation history, as metals provide most of the gas cooling that will facilitate and sustain star formation. Aims: Our primary objective is to study the enrichment of the H i region and the interplay between star-formation history and metallicity evolution. Our secondary objective is to constrain the spatial- and time-scales over which the H i and H ii regions are enriched, and the mass range of stars responsible for the heavy element production. Finally, we aim to examine the gas heating and cooling mechanisms in the H i region. Methods: We observed the most metal-poor star-forming galaxy in the Local Universe, I Zw 18, with the Cosmic Origin Spectrograph onboard Hubble. The abundances in the neutral gas are derived from far-ultraviolet absorption-lines (H i, C ii, C ii*, N i, O i, ...) and are compared to the abundances in the H ii region. Models are constructed to calculate the ionization structure and the thermal processes. We investigate the gas cooling in the H i region through physical diagnostics drawn from the fine-structure level of C+. Results: We find that H i region abundances are lower by a factor of ~2 as compared to the H ii region. There is no differential depletion on dust between the H i and H ii region. Using sulfur as a metallicity tracer, we calculate a metallicity of 1/46 Z? (vs. 1/31 Z? in the H ii region). From the study of the C/O, [O/Fe], and N/O abundance ratios, we propose that C, N, O, and Fe are mainly produced in massive stars. We argue that the H i envelope may contain pockets of pristine gas with a metallicity essentially null. Finally, we derive the physical conditions in the H i region by investigating the C ii* absorption line. The cooling rate derived from C ii* is consistent with collisions with H0 atoms in the diffuse neutral gas. We calculate the star-formation rate from the C ii* cooling rate assuming that photoelectric effect on dust is the dominant gas heating mechanism. Our determination is in good agreement with the values in the literature if we assume a low dust-to-gas ratio (~2000 times lower than the Milky Way value). Appendix A is available in electronic form at http://www.aanda.org

Lebouteiller, V.; Heap, S.; Hubeny, I.; Kunth, D.

2013-05-01

373

Looking North into Lab Metallurgy Testing Area and Enrichment Motor ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Looking North into Lab Metallurgy Testing Area and Enrichment Motor within Recycle Recovery Building - Hematite Fuel Fabrication Facility, Recycle Recovery Building, 3300 State Road P, Festus, Jefferson County, MO

374

21 CFR 137.160 - Enriched bromated flour.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Enriched bromated flour. 137.160 Section 137.160 ...FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.160...

2013-04-01

375

21 CFR 137.185 - Enriched self-rising flour.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Enriched self-rising flour. 137.185 Section 137.185 ...FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.185...

2013-04-01

376

21 CFR 137.185 - Enriched self-rising flour.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Enriched self-rising flour. 137.185 Section 137.185 ...FOOD FOR HUMAN CONSUMPTION CEREAL FLOURS AND RELATED PRODUCTS Requirements for Specific Standardized Cereal Flours and Related Products § 137.185...

2010-04-01

377

Free-Air CO2 Enrichment (FACE) Research Sites  

NSDL National Science Digital Library

FACE, the Free Air Carbon Dioxide Enrichment research program of Brookhaven National Laboratory, provides data summaries on a variety of FACE sites: North Carolina, Nevada, Wisconsin, and Brauschweig (Germany). To access more detailed information, follow links to specific sites.

1969-12-31

378

Accelerating the Reduction of Excess Russian Highly Enriched Uranium.  

National Technical Information Service (NTIS)

This paper presents the latest information on one of the Accelerated Highly Enriched Uranium (HEU) Disposition initiatives that resulted from the May 2002 Summit meeting between Presidents George W. Bush and Vladimir V. Putin. These initiatives are meant ...

J. Benton D. Wall E. Parker E. Rutkowski

2004-01-01

379

Criticality issues with highly enriched fuels in a repository environment.  

National Technical Information Service (NTIS)

This paper presents preliminary analysis of a volcanic tuff repository containing a combination of low enrichment commercial spent nuclear fuels (SNF) and DOE-owned SNF packages. These SNFs were analyzed with respect to their criticality risks. Disposal o...

L. L. Taylor L. C. Sanchez J. S. Rath

1998-01-01

380

Enrichment medium for isolation of Campylobacter jejuni-Campylobacter coli.  

PubMed

A kaseini-broth enrichment medium (KBEM) for the isolation improvement of Campylobacter jejuni-Campylobacter coli from stool samples is described. Isolation of Campylobacters from stool specimens by direct inoculation onto solid selective medium was compared with isolation after twenty-four hours enrichment at 37 degrees C in KBEM, followed by subculture onto the same solid selective medium. Of 156 examined stool samples from diarrhoeal children positive results were obtained from 17 patients altogether: 11 by direct inoculation on selective media and 6 only owing to enrichment. Thus, an increase of 35.3% in the isolation rate was obtained by using the enrichment medium. The same medium allows the preservation of isolates of Campylobacter jejuni-Campylobacter coli for 2 months and longer at 37 degrees C. PMID:9524671

Sicinschi, L A

1995-01-01

381

Running is the neurogenic and neurotrophic stimulus in environmental enrichment  

PubMed Central

Environmental enrichment (EE) increases dentate gyrus (DG) neurogenesis and brain-derived neurotrophic factor (BDNF) levels. However, running is considered an element of EE. To dissociate effects of physical activity and enrichment on hippocampal neurogenesis and BDNF levels, young female C57Bl/6 mice were housed under control, running, enrichment, or enrichment plus running conditions, and injected with bromodeoxyuridine. Cell genesis was assessed after 12 d and differentiation was analyzed 1 mo later. In addition, locomotor activity in the open field and hippocampal mature BDNF peptide levels were measured. Open-field adaptation was improved in all groups, compared to controls, but more so with running. New cell proliferation, survival, neuron number, and neurotrophin levels were enhanced only when running was accessible. We conclude that exercise is the critical factor mediating increased BDNF levels and adult hippocampal neurogenesis.

Kobilo, Tali; Liu, Qing-Rong; Gandhi, Kriti; Mughal, Mohammed; Shaham, Yavin; van Praag, Henriette

2011-01-01

382

Assessing the enrichment performance in targeted resequencing experiments.  

PubMed

Target enrichment strategies are a very common approach to sequence a predefined part of an individual's genome using second-generation sequencing technologies. While highly dependent on the technology and the target sequences selected, the performance of the various assays is also variable between samples and is influenced by the way how the libraries are handled in the laboratory. Here, we show how to find detailed information about the enrichment performance using a novel software package called NGSrich, which we developed as a part of a whole-exome resequencing pipeline in a medium-sized genomics center. Our software is suitable for high-throughput use and the results can be shared using HTML and a web server. Finally, we have sequenced exome-enriched DNA libraries of 18 human individuals using three different enrichment products and used our new software for a comparative analysis of their performance. PMID:22290614

Frommolt, Peter; Abdallah, Ali T; Altmüller, Janine; Motameny, Susanne; Thiele, Holger; Becker, Christian; Stemshorn, Kathryn; Fischer, Matthias; Freilinger, Tobias; Nürnberg, Peter

2012-04-01

383

Unraveling the human dendritic cell phagosome proteome by organellar enrichment ranking.  

PubMed

Dendritic cells (DC) take up pathogens through phagocytosis and process them into protein and lipid fragments for presentation to T cells. So far, the proteome of the human DC phagosome, a detrimental compartment for antigen processing and presentation as well as for DC activation, remains largely uncharacterized. Here we have analyzed the protein composition of phagosomes from human monocyte-derived DC. For LC-MS/MS analysis we purified phagosomes from DC using latex beads targeted to DC-SIGN, and quantified proteins using a label-free method. We used organellar enrichment ranking (OER) to select proteins with a high potential to be relevant for phagosome function. The method compares phagosome protein abundance with protein abundance in whole DC. Phagosome enrichment indicates specific recruitment to the phagosome rather than co-purification or passive incorporation. Using OER we extracted the most enriched proteins that we further complemented with functionally associated proteins to define a set of 90 phagosomal proteins that included many proteins with established relevance on DC phagosomes as well as high potential novel candidates. We already experimentally confirmed phagosomal recruitment of Galectin-9, which has not been previously associated with phagocytosis, to both bead and pathogen containing phagosomes, suggesting a role for Galectin-9 in DC phagocytosis. PMID:22146474

Buschow, Sonja I; Lasonder, Edwin; Szklarczyk, Radek; Oud, Machteld M; de Vries, I Jolanda M; Figdor, Carl G

2012-02-16

384

Review-oriented metadata enrichment: a case study  

Microsoft Academic Search

Book reviews contributed by readers in social sites contain valuable information on books' content, style and merit, many informative words in which can be used to enrich metadata of books in China-Us Million Book Digital Library. In this paper, we present a system for review-oriented metadata enrichment and propose an Book-Centric Diverse Random Walk algorithm on a four-partite graph containing

Liang Zhang; Jiangqin Wu; Yueting Zhuang; Yin Zhang; Chenxing Yang

2009-01-01

385

Enrichment of Named Entities for Image Photo Retrieval  

Microsoft Academic Search

\\u000a This paper describes and discusses an approach to extract and exploit enriched Named Entities for Image Photo Retrieval. The\\u000a enrichment of Named Entities is inspired by the concept of definite description. The approach is evaluated using the imageCLEF-08 testset for the photo retrieval task held at Cross-Language Evaluation\\u000a Forum in 2008. We are particularly interested in testing and discuss whether

Rodrigo Agerri; Ruben Granados; Ana García-Serrano

2009-01-01

386

A microchip for nucleic acid isolation and enrichment  

Microsoft Academic Search

This paper presents a microchip that effectively isolates and enriches target-binding single-stranded DNA (ssDNA) in a randomized DNA mixture using solid-phase extraction (SPE) and electrophoresis. The microchip consists of isolation and enrichment microchambers that are connected by a microchannel partially filled with agarose gel. Single-stranded DNA oligomers in the randomized mixture are captured via specific binding onto human immunoglobulin E

J. Kim; J. P. Hilton; K. A. Yang; R. Pei; K. Ennis; M. Stojanovic; Q. Lin

2012-01-01

387

Degradation of p-xylene by a denitrifying enrichment culture  

SciTech Connect

Microbial cultures enriched from a diesel fuel-contaminated aquifer were able to grow on p-xylene under denitrifying conditions. The oxidation of p-xylene to CO{sub 2} was coupled to the reduction of NO{sub 3}{sup -}. The enrichment cultures also grew on toluene and m-xylene, but they did not degrade benzene, ethylbenzene, and o-xylene. 37 refs., 4 figs.

Haener, A.; Hoehener, P.; Zeyer, J. [Swiss Federal Institute of Technology, Schlieren (Switzerland)

1995-08-01

388

ENVIRONMENTAL ENRICHMENT REDUCES THE MNEMONIC AND NEURAL BENEFITS OF ESTROGEN  

PubMed Central

The degree to which memory is enhanced by estrogen replacement in postmenopausal women may depend on environmental factors such as education. The present study utilized an animal model of environmental enrichment to determine whether environmental factors influence the mnemonic and neural response to estrogen. Female mice were raised in standard (SC) or enriched (EC) conditions from weaning until adulthood (7 months). All mice were ovariectomized at 10 weeks, and tested in object recognition and water-escape motivated radial arm maze (WRAM) tasks at 6 months. Each day at the completion of training, mice received injections of 0.1 mg/kg cyclodextrin-encapsulated 17-?-estradiol (E2), 0.2 mg/kg E2, or cyclodextrin vehicle (VEH). At the completion of behavioral testing, hippocampal levels of the presynaptic protein synaptophysin and of brain-derived neurotrophic factor (BDNF) were measured. Enrichment effects were evident in VEH-treated mice; relative to SC-VEH females, EC-VEH females committed fewer working memory errors in the WRAM and exhibited increased hippocampal synaptophysin levels. Estrogen effects depended on environmental conditions. E2 (0.2 mg/kg) improved object memory only in SC females. The same dose improved working memory in SC females, but somewhat impaired working memory in EC females. Furthermore, both doses reduced hippocampal synaptophysin levels in EC, but not SC, females. In contrast, E2 reduced hippocampal BDNF levels in SC, but not EC, females. This study is the first to compare the effects of estrogen on memory and hippocampal function in enriched and non-enriched female mice. The results suggest that: (1) estrogen benefits object and working memory more in mice raised in non-enriched environments than in those raised in enriched environments, and (2) the changes induced by estrogen and/or enrichment may be associated with alterations in hippocampal synaptic plasticity.

GRESACK, J. E.; FRICK, K. M.

2006-01-01

389

Detection ofMycobacterium tuberculosisin Cerebrospinal Fluid following Immunomagnetic Enrichment  

Microsoft Academic Search

ThedetectionofMycobacteriumtuberculosisbycultureofcerebrospinalfluid(CSF)isunacceptablyslow.Low numbersoforganismsandthepresenceofreactioninhibitorsmaypreventdetectionofM.tuberculosisbyPCR. We used immunomagnetic enrichment to accelerate and enhance the detection of mycobacteria in CSF after demonstrating the utility of the method with pure suspensions. Growth was detected earlier in Bactec cultures of magnetically recovered mycobacteria than in untreated CSF (7 versus 15 days). We detectedM. tuberculosis DNA by PCR in the immunomagnetically enriched sample but not in untreated

GERALD H. MAZUREK; VENKAT REDDY; DAVID MURPHY; ANDTARIQ ANSARI

1996-01-01

390

Semantic enrichment of building and construction knowledge sources using a domain ontology for classification  

NASA Astrophysics Data System (ADS)

The paper introduces a new conceptual framework for representation of knowledge sources (whether they are web pages or documents), where each knowledge source is semantically represented (within its domain of use) by a Semantic Vector (SV), which is enriched using the classical vector space model approach extended with ontological support, employing ontology concepts and their relations in the enrichment process. The test domain for the assessment of the approach is the Building and Construction, using an appropriate available Ontology. Preliminary results were collected using a clustering algorithm for document classification where documents were assigned into a pre-defined set of categories. Such results indicate that the proposed approach does improve the precision and recall of classifications.

Costa, Ruben; Lima, Celson; Sarraipa, Joa~o.; Jardim-Gonçalves, Ricardo

2013-10-01

391

Three Phases of Plant Response to Atmospheric CO2 Enrichment 1  

PubMed Central

Several years of research on seven different plants (five terrestrial and two aquatic species) suggest that the beneficial effects of atmospheric CO2 enrichment may be divided into three distinct growth response phases. First is a well-watered optimum-growth-rate phase where a 300 parts per million increase in the CO2 content of the air generally increases plant productivity by approximately 30%. Next comes a nonlethal water-stressed phase where the same increase in atmospheric CO2 is more than half again as effective in increasing plant productivity. Finally, there is a water-stressed phase normally indicative of impending death, where atmospheric CO2 enrichment may actually prevent plants from succumbing to the rigors of the environment and enable them to maintain essential life processes, as life ebbs from corresponding ambient-treatment plants.

Idso, Sherwood B.

1988-01-01

392

Three phases of plant response to atmospheric CO sub 2 enrichment  

SciTech Connect

Several years of research on seven different plants (five terrestrial and two aquatic species) suggest that the beneficial effects of atmospheric CO{sub 2} enrichment may be divided into three distinct growth response phases. First is a well-watered optimum-growth-rate phase where a 300 parts per million increase in the CO{sub 2} content of the air generally increases plant productivity by approximately 30%. Next comes a nonlethal water-stressed phase where the same increase in atmospheric CO{sub 2} is more than half again as effective in increasing plant productivity. Finally, there is a water-stressed phase normally indicative of impending death, where atmospheric CO{sub 2} enrichment may actually prevent plants from succumbing to the rigors of the environment and enable them to maintain essential life processes, as life ebbs from corresponding ambient-treatment plants.

Idso, S.B. (Water Conservation Laboratory, Phoenix, AZ (USA))

1988-05-01

393

Enrichment can decrease NO{sub x}, SO{sub x} formation  

SciTech Connect

One of the key issues associated with fluid catalytic cracking (FCC) unit operations and debottlenecking options is the effects of process variables and operational modes on regenerator-related NO{sub x} and SO{sub x} emissions. This second of 2 articles on FCC oxygen enrichment explains regenerator NO{sub x}-formation pathways and summarizes the effects of variations in the regenerator environment, including regenerator gas and solids compositions, on these pathways. Also reported are results indicating that operation with oxygen enrichment can improved the effectiveness, of SO{sub x}-transfer additives. The first article in this series described advances in oxygen-production technology and presented results from materials-compatibility studies.

Tamhankar, S.; Menon, R.; Chou, T. [BOC Group Inc., Murray Hill, NJ (United States); Ramachandran, R. [BOC Gases, Murray Hill, NJ (United States); Hull, R. [BOC Gases--Americas, Murray Hill, NJ (United States); Watson, R. [BOC Gases--Europe, Surrey (United Kingdom)

1996-03-04

394

Enrichment-toy trauma in a New Zealand White rabbit.  

PubMed

An injury was caused by an enrichment toy (a whiffle ball, which is a perforated hollow ball made of hard plastic) that led to its removal from the rabbit enrichment program. Manipulata and food treats form the basis of the Yale rabbit enrichment program. All singly housed rabbits are given toys such as balls, chains, wood blocks, PVC tubing, Nylabones, and corrugated plastic tunnels. Before they are used, all potential enrichment devices are reviewed for safety and potential veterinary problems. The whiffle ball had been considered safe because it was made of hard non-toxic plastic, had no sharp edges, was too large to be swallowed or inhaled, and was judged too sturdy to be broken by the rabbits. However, the ball became lodged in the incisors of an adult female New Zealand White rabbit, preventing her from eating or drinking for 12 h and causing marked trauma to her gums. Removal of the ball necessitated anesthetizing the rabbit and using bone cutters to cut away the ball. Ideally, environmental enrichment should increase species-specific normal behavior and minimize stereotypies and self- and conspecific-directed abusive behavior. This case illustrates that safety assessments for an enrichment device must include both the inherent properties of the device and the risks if the toy is misused or damaged. Considerations for safety assessment are discussed. PMID:11300673

Shomer, N H; Peikert, S; Terwilliger, G

2001-01-01

395

Experimental evidence of nitrogen control on pCO2 in phosphorus-enriched humic and clear coastal lagoon waters  

PubMed Central

Natural and human-induced controls on carbon dioxide (CO2) in tropical waters may be very dynamic (over time and among or within ecosystems) considering the potential role of warmer temperatures intensifying metabolic responses and playing a direct role on the balance between photosynthesis and respiration. The high magnitude of biological processes at low latitudes following eutrophication by nitrogen (N) and phosphorus (P) inputs into coastal lagoons waters may be a relevant component of the carbon cycle, showing controls on partial pressure of CO2 (pCO2) that are still poorly understood. Here we assessed the strength of N control on pCO2 in P-enriched humic and clear coastal lagoons waters, using four experimental treatments in microcosms: control (no additional nutrients) and three levels of N additions coupled to P enrichments. In humic coastal lagoons waters, a persistent CO2 supersaturation was reported in controls and all nutrient-enriched treatments, ranging from 24- to 4-fold the atmospheric equilibrium value. However, both humic and clear coastal lagoons waters only showed significant decreases in pCO2 in relation to the controlled microcosms in the two treatments with higher N addition levels. Additionally, clear coastal lagoons water microcosms showed a shift from CO2 sources to CO2 sinks, in relation to the atmosphere. Only in the two more N-enriched treatments did pCO2 substantially decrease, from 650 µatm in controls and less N-enriched treatments to 10 µatm in more N-enriched microcosms. Humic substrates and N inputs can modulate pCO2 even in P-enriched coastal lagoons waters, thereby being important drivers on CO2 outgassing from inland waters.

Peixoto, Roberta B.; Marotta, Humberto; Enrich-Prast, Alex

2013-01-01

396

Experimental evidence of nitrogen control on pCO(2) in phosphorus-enriched humic and clear coastal lagoon waters.  

PubMed

Natural and human-induced controls on carbon dioxide (CO(2)) in tropical waters may be very dynamic (over time and among or within ecosystems) considering the potential role of warmer temperatures intensifying metabolic responses and playing a direct role on the balance between photosynthesis and respiration. The high magnitude of biological processes at low latitudes following eutrophication by nitrogen (N) and phosphorus (P) inputs into coastal lagoons waters may be a relevant component of the carbon cycle, showing controls on partial pressure of CO(2) (pCO(2)) that are still poorly understood. Here we assessed the strength of N control on pCO(2) in P-enriched humic and clear coastal lagoons waters, using four experimental treatments in microcosms: control (no additional nutrients) and three levels of N additions coupled to P enrichments. In humic coastal lagoons waters, a persistent CO(2) supersaturation was reported in controls and all nutrient-enriched treatments, ranging from 24- to 4-fold the atmospheric equilibrium value. However, both humic and clear coastal lagoons waters only showed significant decreases in pCO(2) in relation to the controlled microcosms in the two treatments with higher N addition levels. Additionally, clear coastal lagoons water microcosms showed a shift from CO(2) sources to CO(2) sinks, in relation to the atmosphere. Only in the two more N-enriched treatments did pCO(2) substantially decrease, from 650 µatm in controls and less N-enriched treatments to 10 µatm in more N-enriched microcosms. Humic substrates and N inputs can modulate pCO(2) even in P-enriched coastal lagoons waters, thereby being important drivers on CO(2) outgassing from inland waters. PMID:23390422

Peixoto, Roberta B; Marotta, Humberto; Enrich-Prast, Alex

2013-01-01

397

A first principles approach to supergene enrichment of a porphyry copper protore: I. Cu-Fe-S subsystem  

NASA Astrophysics Data System (ADS)

A unified description of supergene enrichment of a porphyry copper protore is presented based on the principles of metasomatic zoning. Mathematically this formulation represents the supergene weathering process as a moving boundary problem. A first principles approach is used to describe quantitatively the transport of oxygenated water through a porous host rock consisting of a Cu-bearing protore. Mineral reaction rates are represented by kinetic rate expressions for both precipitation and dissolution. Reaction zones containing mineral alteration products making up a leached zone, oxide zone, and enrichment blanket propagate downward in the direction of fluid transport. The time evolution of the system is completely determined by the governing transport equations once initial and boundary conditions are specified, giving the composition of the unaltered host rock and infiltrating fluid entering at the surface of the weathering column. The description provides for both fully saturated conditions and undersaturated conditions in the presence of a water table at depth. An order of magnitude estimate of the velocity of propagation of a redox front demonstrates that metasomatic effects become increasingly important as the O content of the infiltrating water increases. Regions of higher permeability, resulting in higher fluid flow velocities, lead to increased enrichment compared to regions of lower permeability, with reduced flow velocities, in agreement with field observations. Results of numerical calculations suggest that the enrichment blanket may be subdivided into three distinct zones: (1) an enriched zone at the top of the blanket (2) the middle blanket in which chemical reactions of Cu-bearing minerals are absent; and (3) the nascent blanket forming the interface between the protore and middle blanket. Both the nascent and middle blanket contain the same Cu grade as the protore. These results are in agreement with field observations of a high Cu grade within a relatively narrow zone in the upper portion of the blanket. Results of numerical calculations for three different scenarios are presented. The first example considers a simplified representation of the enrichment process with chalcopyrite, covellite, and chalcocite as the major Cu minerals. In this case chalcocite forms an enriched zone at the top of the blanket which migrates downward increasing in width. The second and third examples differ by the presence of a water table at depth, and include brochantite, tenorite, native Cu, and cuprite as secondary Cu minerals in addition to the minerals used in the first example. Surprisingly, in these two examples the enriched blanket zone does not grow indefinitely with time, but reaches a steady-state profile that is displaced rigidly in the direction of fluid transport without changing shape. In the presence of a water table at depth, the major enrichment occurs in the oxide zone lying above the blanket.

Lichtner, Peter C.; Biino, Giuseppe G.

1992-11-01

398

PREPARING THE HIGH FLUX ISOTOPE REACTOR FOR CONVERSION TO LOW ENRICHED URANIUM FUEL ? RETURN TO 100 MW  

SciTech Connect

The feasibility of low-enriched uranium (LEU) fuel as a replacement for the current, high enriched uranium (HEU) fuel for the High Flux Isotope Reactor (HFIR) has been under study since 2006. Reactor performance studies have been completed for conceptual plate designs and show that maintaining reactor performance while converting to LEU fuel requires returning the reactor power to 100 MW from 85 MW. The analyses required to up-rate the reactor power and the methods to perform these analyses are discussed. Comments regarding the regulatory approval process are provided along with a conceptual schedule.

Smith, Kevin Arthur [ORNL; Primm, Trent [ORNL

2009-01-01

399

Building Science Process Skills  

ERIC Educational Resources Information Center

A well-designed and executed field trip experience serves not only to enrich and supplement course content, but also creates opportunities to build basic science process skills. The National Science Education Standards call for science teachers "to design and manage learning environments that provide students with the time, space, and resources…

DeFina, Anthony V.

2006-01-01

400

Building Science Process Skills  

NSDL National Science Digital Library

A well-designed and executed field trip experience serves not only to enrich and supplement course content, but also creates opportunities to build basic science process skills. This article describes an onsite trip to the Bronx Zoo that allowed collaborating students to develop acquisitive and organizational skills while exploring rain forest habitat characteristics and species diversity.

Defina, Anthony V.

2006-01-01

401

An Optically Stimulated Luminescence Uranium Enrichment Monitor  

Microsoft Academic Search

The Pacific Northwest National Laboratory (PNNL) has pioneered the use of Optically Stimulated Luminescence (OSL) technology for use in personnel dosimetry and high dose radiation processing dosimetry. PNNL has developed and patented an alumina-based OSL dosimeter that is being used by the majority of medical X-ray and imaging technicians worldwide. PNNL has conceived of using OSL technology to passively measure

Steven D. Miller; Jennifer E. Tanner; Kevin L. Simmons; Matthew M. Conrady; Jacob M. Benz; Bryce A. Greenfield

2010-01-01

402

The oxygen isotope enrichment of leaf-exported assimilates - does it always reflect lamina leaf water enrichment?  

PubMed Central

The oxygen stable isotope composition of plant organic matter (OM) (particularly of wood and cellulose in the tree ring archive) is valuable in studies of plant–climate interaction, but there is a lack of information on the transfer of the isotope signal from the leaf to heterotrophic tissues. We studied the oxygen isotopic composition and its enrichment above source water of leaf water over diel courses in five tree species covering a broad range of life forms. We tracked the transfer of the isotopic signal to leaf water-soluble OM and further to phloem-transported OM. Observed leaf water evaporative enrichment was consistent with values predicted from mechanistic models taking into account nonsteady-state conditions. While leaf water-soluble OM showed the expected 18O enrichment in all species, phloem sugars were less enriched than expected from leaf water enrichment in Scots pine (Pinus sylvestris), European larch (Larix decidua) and Alpine ash (Eucalyptus delegatensis). Oxygen atom exchange with nonenriched water during phloem loading and transport, as well as a significant contribution of assimilates from bark photosynthesis, can explain these phloem 18O enrichment patterns. Our results indicate species-specific uncoupling between the leaf water and the OM oxygen isotope signal, which is important for the interpretation of tree ring data.

Gessler, Arthur; Brandes, Elke; Keitel, Claudia; Boda, Sonja; Kayler, Zachary E; Granier, Andre; Barbour, Margaret; Farquhar, Graham D; Treydte, Kerstin

2013-01-01

403

Informal criticality safety analysis report for UND project. Part I. 2. 1 wt. % enriched UOâ(NOâ)â. 2HâO  

Microsoft Academic Search

The cold canyon (EDL-102) and the adjoining laboratory sections which comprise the west side of the 324 Building are to be established under criticality specification control for the processing of up to 1500 pounds of 2.1% enriched uranium as uranyl nitrate dihydrate (UND). The 2.1% enriched uranyl nitrate dihydrate has no critical mass. However, if the UND were converted to

Schwab

1967-01-01

404

Stoichiometric and molecular evidence for the enrichment of anaerobic ammonium oxidizing bacteria from wastewater treatment plant sludge samples.  

PubMed

Anammox enrichments were readily developed from seven municipal wastewater treatment plants (WWTPs) sludge, but not with methanogenic granular sludge from two agro-industrial WWTPs. Only 50d was required for the first evidence of anammox activity from a return activated sludge obtained from a WWTP operated for nutrient removal. The molar ratios of nitrite and ammonium consumption of approximately 1.32 as well as nitrate and dinitrogen gas product ratios of approximately 0.095 provided evidence of the anammox reaction. The presence of anammox was confirmed by polymerase chain reaction (PCR) using primer sets (PLA46F and AMX820R) specific for anammox bacteria. The 16S rRNA gene fragment of anammox bacteria was detected in seven enrichment cultures (ECs) with demonstrated anammox activity but not in the original inocula from which the ECs were derived and also not in the two methanogenic sludge samples, which indicates the PCR predicted the anammox activity. Two genera, Brocadia and Kuenenia, were successfully identified as the Planctomycetes occurring in the clone libraries of successful anammox enrichments. Brocadia dominated in cultures that were respiked extensively; whereas Kuenenia predominated in cultures that were less aggressively respiked. These findings indicate that respiking management may play an important role on selecting the genus of anammox bacteria. The batch enrichment results clearly illustrate that anammox can be readily enriched from municipal sludge from a wide variety of process operations at WWTPs. PMID:21620436

Sun, Wenjie; Banihani, Qais; Sierra-Alvarez, Reyes; Field, Jim A

2011-08-01

405

Contrasting resource limitations of marine primary producers: implications for competitive interactions under enriched CO2 and nutrient regimes.  

PubMed

Primary producers rarely exist under their ideal conditions, with key processes often limited by resource availability. As human activities modify environmental conditions, and therefore resource availability, some species may be released from these limitations while others are not, potentially disrupting community structure. In order to examine the limitations experienced by algal functional groups that characterise alternate community structures (i.e. turf-forming algae and canopy-forming kelp), we exposed these groups to contemporary and enriched levels of carbon dioxide (CO2) and nutrients. Turfs responded to the individual enrichment of both CO2 and nutrients, with the greatest shift in the biomass and carbon:nitrogen (C:N) ratios observed under their combined enrichment. In contrast, kelp responded to enriched nutrients, but not enriched CO2. We hypothesise that the differing limitations reflect the contrasting physiologies of these functional groups, specifically their methods of C acquisition, such as the possession and/or efficiency of a carbon concentrating mechanism (CCM). Importantly, our results reveal that these functional groups, whose interactions structure entire communities, experience distinct resource limitations, with some potentially limited by a single type of resource (i.e. kelp by nutrients), while others may be co-limited (i.e. turf by CO2 and nutrients). Consequently, the identification of how alternate conditions modify resource availability and limitations may facilitate anticipation of the future sustainability of major ecosystem components and the communities they support. PMID:23111809

Falkenberg, Laura J; Russell, Bayden D; Connell, Sean D

2013-06-01

406

[Characteristics and mechanism of 2,4,6-TCP degradation by the "Fe0/enriched-bacteria" system].  

PubMed

The synergistic mechanism of 2, 4, 6-trichlorophenol (TCP) degradation using a combination of Fe0 and anaerobic dechlorinating bacteria with batch processing was investigated. Experimental results showed that under the conditions of pH 7.0, Fe0 5 g x L(-1) and 2,4,6-TCP 30 mg x L(-1), the growth and interface enrichment of enriched-bacteria could be promoted by Fe0, the cell mass (expressed by D600) of Fe0/enriched-bacteria was about 1.7 times as high as that of the individual predominant groups of dechlorinating bacteria. After 96 h reaction, large amount of bacteria attached to the iron surface, with short rod or coccus-like morphology. The pH value of the system was maintained at 7.8, which could be beneficial to the reductive dechlorination reaction and the growth of the enriched-bacteria. The major pathway of 2,4,6-TCP degradation in the Fe0/enriched-bacteria system was 2,4,6-TCP to 2,4-DCP and then to 4-CP. PMID:23213899

Dai, You-zhi; Guo, Li-li; Shi, Lei; Liu, Zhi-yong; Gao, Bao-chai

2012-08-01

407

Surface reactions of iron - enriched smectites: adsorption and transformation of hydroxy fatty acids and phenolic acids  

NASA Astrophysics Data System (ADS)

Iron-enriched smectites play an important role in adsorption and transformation of soil organic components. Soil organo-clay complexes, and in particular humin contain hydroxy fatty acids, which are derived from plant biopolymer cutin. Phenolic acids belong to another major group of organic acids detected in soil. They participate in various soil processes, and are of concern due to their allelopathic activity. We studied the reactivity of iron-enriched smectites (Fe(III)-montmorillonite and nontronite) toward both groups of acids. We used fatty acids- 9(10),16-dihydroxypalmitic acid (diHPA), isolated from curtin, and 9,10,16-trihydroxypalmitic acid (triHPA); the following phenolic acids were used: ferulic, p-coumaric, syringic, and vanillic. Adsorption of both groups of acids was measured. The FTIR spectra of fatty acid-mineral complexes indicated inner-sphere complexation of fatty acids with iron-enriched smectites (versus outer-sphere complexation with Ca(II)-montmorillonite). The LC-MS results demonstrated enhanced esterification of fatty acids on the iron-enriched smectite surfaces (as compared to Ca(II)-montmorillonite). This study suggests that fatty acids can be esterified on the iron-enriched smectite surfaces, which results in the formation of stable organo-mineral complexes. These complexes may serve as a model for the study of natural soil organo-clay complexes and humin. The reaction of phenolic acids with Fe(III)-montmorillonite demonstrated their oxidative transformation by the mineral surfaces, which was affected by molecular structure of acids. The following order of their transformation was obtained: ferulic >syringic >p-coumaric >vanillic. The LC-MS analysis demonstrated the presence of dimers, trimers, and tetramers of ferulic acid on the surface of Fe(III)-montmorillonite. Oxidation and transformation of ferulic acid were more intense on the surface of Fe(III)-montmorillonite as compared to Fe(III) in solution due to stronger complexation on the Fe(III)-motnomrillonite surface. Our study demonstrate the importance of iron-enriched minerals for the abiotic formation of humic materials and for the transformation of aromatic (phenolic) pollutants.

Polubesova, Tamara; Olshansky, Yaniv; Eldad, Shay; Chefetz, Benny

2014-05-01

408

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

SciTech Connect

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.

NONE

1994-12-01

409

Semantically enriched data for effective sensor data fusion  

NASA Astrophysics Data System (ADS)

Data fusion plays a major role in assisting decision makers by providing them with an improved situational awareness so that informed decisions could be made about the events that occur in the field. This involves combining a multitude of sensor modalities such that the resulting output is better (i.e., more accurate, complete, dependable etc.) than what it would have been if the data streams (hereinafter referred to as 'feeds') from the resources are taken individually. However, these feeds lack any context-related information (e.g., detected event, event classification, relationships to other events, etc.). This hinders the fusion process and may result in creating an incorrect picture about the situation. Thus, results in false alarms, waste valuable time/resources. In this paper, we propose an approach that enriches feeds with semantic attributes so that these feeds have proper meaning. This will assist underlying applications to present analysts with correct feeds for a particular event for fusion. We argue annotated stored feeds will assist in easy retrieval of historical data that may be related to the current fusion. We use a subset of Web Ontology Language (OWL), OWL-DL to present a lightweight and efficient knowledge layer for feeds annotation and use rules to capture crucial domain concepts. We discuss a solution architecture and provide a proof-of-concept tool to evaluate the proposed approach. We discuss the importance of such an approach with a set of user cases and show how a tool like the one proposed could assist analysts, planners to make better informed decisions.

de Mel, Geeth; Pham, Tien; Damarla, Thyagaraju; Vasconcelos, Wamberto; Norman, Tim

2011-05-01

410

Potato skin proteome is enriched with plant defence components  

PubMed Central

Periderm is a tissue of secondary origin that replaces damaged epidermis. It can be found in underground plant organs, as an above-ground tissue of woody species (cork), and as a wound-healing tissue. Its outer layers are composed of phellem cells with suberized walls that constitute a protective barrier, preventing pathogen invasion and fluid loss. In potato, a model for periderm studies, periderm tissue replaces the epidermis early in tuber development and the suberized phellems constitute the tuber's skin. To identify factors involved in phellem/skin development and that play a role in its defensive characteristics, two-dimensional gel electrophoresis was used to compare the skin and parenchymatic flesh proteomes of young developing tubers. Proteins exhibiting differentially high signal intensity in the skin were sorted by functional categories. As expected, the differential skin proteome was enriched in proteins whose activity is characteristic of actively dividing tissues such as cell proliferation, C1 metabolism, and the oxidative respiratory chain. Interestingly, the major functional category consisted of proteins (63%) involved in plant defence responses to biotic and abiotic stresses. This group included three isozymes of caffeoyl-CoA O-methyltransferase and five isozymes of peroxidase that may play a role in suberization processes. The differential expression of these proteins in the skin was further verified by RT-PCR of their corresponding transcripts in skin and tuber flesh samples. The results presented here shed light on the early events in skin development and further expand the concept of the periderm as a protective tissue containing an array of plant defence components.

Barel, Gilli; Ginzberg, Idit

2008-01-01

411

Recovery of three arctic stream reaches from experimental nutrient enrichment  

USGS Publications Warehouse

1. Nutrient enrichment and resulting eutrophication is a widespread anthropogenic influence on freshwater ecosystems, but recovery from nutrient enrichment is poorly understood, especially in stream environments. We examined multi-year patterns in community recovery from experimental low-concentration nutrient enrichment (N + P or P only) in three reaches of two Arctic tundra streams (Kuparuk River and Oksrukuyik Creek) on the North Slope of Alaska (U.S.A.). 2. Rates of recovery varied among community components and depended on duration of enrichment (2-13 consecutive growing seasons). Biomass of epilithic algae returned to reference levels rapidly (within 2 years), regardless of nutrients added or enrichment duration. Aquatic bryophyte cover, which increased greatly in the Kuparuk River only after long-term enrichment (8 years), took 8 years of recovery to approach reference levels, after storms had scoured most remnant moss in the recovering reach. 3. Multi-year persistence of bryophytes in the Kuparuk River appeared to prevent recovery of insect populations that had either been positively (e.g. the mayfly Ephemerella, most chironomid midge taxa) or negatively (e.g. the tube-building chironomid Orthocladius rivulorum) affected by this shift in dominant primary producer. These lags in recovery (of >3 years) were probably driven by the persistent effect of bryophytes on physical benthic habitat. 4. Summer growth rates of Arctic grayling (both adults and young-of-year) in Oksrukuyik Creek (fertilised for 6 years with no bryophyte colonisation), which were consistently increased by nutrient addition, returned to reference rates within 1-2 years. 5. Rates of recovery of these virtually pristine Arctic stream ecosystems from low-level nutrient enrichment appeared to be controlled largely by duration of enrichment, mediated through physical habitat shifts caused by eventual bryophyte colonisation, and subsequent physical disturbance that removed bryophytes. Nutrient enrichment of oligotrophic Arctic stream ecosystems caused by climate change or local anthropogenic activity may have dramatic and persistent consequences if it results in the colonisation of long-lived primary producers that alter physical habitat. ?? 2007 The Authors.

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

2007-01-01

412

[The accreditation, source of knowledge and enrichment].  

PubMed

On the way for the accreditation which should lead us until 2020, we wish to share some reflections stemming from the daily practice concerning the compulsory quality approach for everyone. Several themes as training and skills evaluation, external quality controls, risk management and action plans have a great relevance and are a matter of public concern. Their consideration contributes not only to the reassurance of processes but also to knowledge improvement. In the following paragraphs we will present an overview of these themes which are all key elements for project management. PMID:24736149

Klein, Jean-Paul

2014-01-01

413

Isolation and Enrichment of Stem Cells  

NASA Astrophysics Data System (ADS)

Stem cells have the potential to revolutionize tissue regeneration and engineering. Both general types of stem cells, those with pluripotent differentiation potential as well as those with multipotent differentiation potential, are of equal interest. They are important tools to further understanding of general cellular processes, to refine industrial applications for drug target discovery and predictive toxicology, and to gain more insights into their potential for tissue regeneration. This chapter provides an overview of existing sorting technologies and protocols, outlines the phenotypic characteristics of a number of different stem cells, and summarizes their potential clinical applications.

Bosio, Andreas; Huppert, Volker; Donath, Susan; Hennemann, Petra; Malchow, Michaela; Heinlein, Uwe A. O.

414

Enrichment culture can bias the isolation of Campylobacter subtypes.  

PubMed

Enrichment culture is often used to isolate Campylobacter. This study compared isolation of Campylobacter spp. from 119 broiler chicken environments from two farms, using Preston and modified Exeter (mExeter) and modified Bolton (mBolton) enrichments. mExeter was significantly more effective in isolating Campylobacter spp. from the environmental samples compared to Preston (P<0.001) and mBolton (P<0.04) broths but there was no significant difference between the latter two methods (P>0.05). Enrichment broth type did not affect isolation from chicken faecal or soil and litter samples. C. jejuni was isolated from significantly more environmental samples using mExeter broth compared to Preston (P<0.01) and mBolton (P<0.003) broths; there was no difference between the latter two methods or between all methods for detection of C. coli (P>0.05). Only C. coli was isolated from the soil and litter samples and although both C. jejuni and C. coli were recovered from the faecal samples there was no effect of using different enrichment broths. The majority of samples where the same species had been isolated yielded the same or closely related genotypes as defined by pulsed-field gel electrophoresis. Isolates recovered using Preston and mBolton broths were less genetically diverse than those from mExeter broth. We conclude that the enrichment method used affects both the number and species of Campylobacter isolated from naturally contaminated samples. PMID:21923970

Williams, L K; Sait, L C; Cogan, T A; Jørgensen, F; Grogono-Thomas, R; Humphrey, T J

2012-07-01

415

Phosphopeptide enrichment using microscale titanium dioxide solid phase extraction.  

PubMed

Identification of phosphopeptides by MS is challenging due to their relatively low abundance in proteomic samples and their limited ionization efficiency. Various affinity enrichment methods have been used in the literature. Titanium dioxide SPE devices have been recently proposed as an alternative to immobilized metal affinity chromatography for phosphopeptide enrichment. This study evaluates the TiO(2 )method using sorbent packed in a 96 well microscale extraction plate operated using a vacuum manifold. The phosphopeptide recovery and enrichment selectivity were investigated at various loading conditions. The effectiveness of organic additives such as dihydroxybenzoic acid derivatives and other nonaliphatic carboxylic acids on enrichment selectivity was examined. The performance of TiO(2) was compared to IMAC sorbent. The results suggest that various additives improve the enrichment selectivity by effectively interfering with the acidic peptides binding to TiO(2) sorbent. Interaction of phosphopeptides with sorbent is also affected, which leads to overall reduction in phosphopeptide recovery. The new SPE device was successfully utilized for the extraction of phosphopeptides from yeast lysate digest using 2,5-dihydroxybenzoic acid to minimize the interference from nonphosphorylated peptides. PMID:19301321

Yu, Ying-Qing; Fournier, Jennifer; Gilar, Martin; Gebler, John C

2009-04-01

416

A short and valid measure of work-family enrichment.  

PubMed

The stream of research concerning work-family enrichment has generated a significant body of research because it plays an important role in occupational health (Masuda, McNall, Allen, & Nicklin, 2012). work-family enrichment has been defined as "the extent to which experiences in one role improve the quality of life in the other role" (Greenhaus & Powell, 2006, p. 73). Within work-family enrichment, there are two directions: work to family and family to work. Carlson, Kacmar, Wayne, and Grzywacz (2006) developed an 18-item scale to measure this construct. Although the scale has been shown to be both reliable and valid, it also requires work-family researchers to include a proportionally large number of items to capture this construct in a study. The goal of the current study was to isolate a subset of the items in this measure that produces results similar to the full version thereby providing a more streamlined scale for researchers. Using a five-sample study that follows the scale reduction procedures offered by Stanton, Sinar, Balzer, and Smith (2002), we provide evidence that scales containing only three items for each direction of enrichment produce results equivalent to the full scale with respect to reliability and discriminant, convergent, and predictive validity. Reducing the original scale by two thirds, without losing explanatory power, allows scholars to measure enrichment in the work and family domains more efficiently, which should help minimize survey time, lower refusal rates, and generate less missing data. PMID:24447219

Kacmar, K Michele; Crawford, Wayne S; Carlson, Dawn S; Ferguson, Merideth; Whitten, Dwayne

2014-01-01

417

Surface enrichment of niobium on Inconel 718 (100) single crystals  

NASA Astrophysics Data System (ADS)

The surface composition of an Inconel 718 (100) single crystal was investigated by X-ray photoelectron spectroscopy over the temperature range 300 to 1000 K in ultra-high vacuum (UHV). The surface composition of an ion etched surface closely resembled the bulk alloy composition determined by atomic absorption spectroscopy. The composition of the ion etched surface remained close to the bulk composition until the temperature was raised above 800 K. At temperatures above 800 K, a dramatic enrichment of surface niobium (Nb) occurred. The extent of Nb enrichment was highly influenced by the presence of trace amounts of surface or subsurface oxygen. Numerous cycles of ion etching and annealing led to nearly complete removal of oxygen from the surface and subsurface region. Surface enrichment of Nb at high temperatures on these oxygen-free surfaces was greatly reduced. However, extensive Nb enrichment could be easily reintroduced by pre-exposure of the surface to oxygen prior to high-temperature vacuum annealing. The evolution of CO during the high-temperature anneal suggested that oxygen attack of the Nb carbide particles played a role in the mechanism of surface enrichment.

Dwyer, D. J.; Pang, X. J.; Gao, M.; Wei, R. P.

1994-10-01

418

Dechlorination of Chlorocatechols by Stable Enrichment Cultures of Anaerobic Bacteria  

PubMed Central

Metabolically stable anaerobic cultures obtained by enrichment with 5-bromovanillin, 5-chlorovanillin, catechin, and phloroglucinol were used to study dechlorination of chlorocatechols. A high degree of specificity in dechlorination was observed, and some chlorocatechols were appreciably more resistant to dechlorination than others: only 3,5-dichlorocatechol, 4,5-dichlorocatechol, 3,4,5-trichlorocatechol, and tetrachlorocatechol were dechlorinated, and not all of them were dechlorinated by the same consortium. 3,5-Dichlorocatechol produced 3-chlorocatechol, 4,5-dichlorocatechol produced 4-chlorocatechol, and 3,4,5-trichlorocatechol produced either 3,5-dichlorocatechol or 3,4-dichlorocatechol; tetrachlorocatechol produced only 3,4,6-trichlorocatechol. Incubation of uncontaminated sediments without additional carbon sources brought about dechlorination of 3,4,5-trichlorocatechol to 3,5-dichlorocatechol. O-demethylation of chloroguaiacols was generally accomplished by enrichment cultures, except that catechin enrichment was unable to O-demethylate tetrachloroguaiacol. None of the enrichments dechlorinated any of the polychlorinated phenols examined. The results suggested that dechlorination was not dependent on enrichment with or growth at the expense of chlorinated compounds and that it would be premature to formulate general rules for the structural dependence of the dechlorination reaction.

Allard, Ann-Sofie; Hynning, Per-Ake; Lindgren, Carin; Remberger, Mikael; Neilson, Alasdair H.

1991-01-01

419

Autologous Antibody Capture to Enrich Immunogenic Viruses for Viral Discovery  

PubMed Central

Discovery of new viruses has been boosted by novel deep sequencing technologies. Currently, many viruses can be identified by sequencing without knowledge of the pathogenicity of the virus. However, attributing the presence of a virus in patient material to a disease in the patient can be a challenge. One approach to meet this challenge is identification of viral sequences based on enrichment by autologous patient antibody capture. This method facilitates identification of viruses that have provoked an immune response within the patient and may increase the sensitivity of the current virus discovery techniques. To demonstrate the utility of this method, virus discovery deep sequencing (VIDISCA-454) was performed on clinical samples from 19 patients: 13 with a known respiratory viral infection and 6 with a known gastrointestinal viral infection. Patient sera was collected from one to several months after the acute infection phase. Input and antibody capture material was sequenced and enrichment was assessed. In 18 of the 19 patients, viral reads from immunogenic viruses were enriched by antibody capture (ranging between 1.5x to 343x in respiratory material, and 1.4x to 53x in stool). Enriched reads were also determined in an identity independent manner by using a novel algorithm Xcompare. In 16 of the 19 patients, 21% to 100% of the enriched reads were derived from infecting viruses. In conclusion, the technique provides a novel approach to specifically identify immunogenic viral sequences among the bulk of sequences which are usually encountered during virus discovery metagenomics.

Deijs, Martin; Jonkers, Jiri; Verhoeven, Joost T. P.; Ieven, Margareta; Goossens, Herman; de Jong, Menno D.; Berkhout, Ben; Loens, Katherine; Kellam, Paul; Bakker, Margreet; Canuti, Marta; Cotten, Matthew; van der Hoek, Lia

2013-01-01

420

Magic angle spinning NMR experiments for structural studies of differentially enriched protein interfaces and protein assemblies.  

PubMed

Protein-protein interactions play vital roles in numerous biological processes. These interactions often result in formation of insoluble and noncrystalline protein assemblies. Solid-state NMR spectroscopy is rapidly emerging as a premier method for structural analysis of such systems. We introduce a family of two-dimensional magic angle spinning (MAS) NMR experiments for structural studies of differentially isotopically enriched protein assemblies. Using 1-73((13)C,(15)N)/74-108((15)N) labeled thioredoxin reassembly, we demonstrate that dipolar dephasing followed by proton-assisted heteronuclear magnetization transfer yields long-range (15)N-(13)C correlations arising exclusively from the interfaces formed by the pair of differentially enriched complementary fragments of thioredoxin. Incorporation of dipolar dephasing into the (15)N proton-driven spin diffusion and into the (1)H-(15)N FSLG-HETCOR sequences permits (1)H and (15)N resonance assignments of the 74-108((15)N) enriched C-terminal fragment of thioredoxin alone. The differential isotopic labeling scheme and the NMR experiments demonstrated here allow for structural analysis of both the interface and each interacting protein. Isotope editing of the magnetization transfers results in spectral simplification, and therefore larger protein assemblies are expected to be amenable to these experiments. PMID:18393505

Yang, Jun; Tasayco, Maria Luisa; Polenova, Tatyana

2008-04-30

421

Amazon capims (floating grassmats): A source of sup 13 C enriched methane to the troposphere  

SciTech Connect

The {sup 13}C isotope composition of methane emitted to the troposphere from Amazon capims (floating grassmats) ranged from {minus}36.9 to {minus}48.0{per thousand} averaging {minus}44.4 {plus minus} 4.2{per thousand}. All pools of methane associated with the grassmats were {sup 13}C enriched; methane withdrawn from plant stems ranged from {minus}39 to {minus}49{per thousand} while bubbles stirred from the root mat averaged {minus}41.4{per thousand}. As the CH{sub 4} flux from these habitats makes up some 40% of the total flux from the Amazon flooplain, CH{sub 4} emissions form the region as a whole must be enriched in the heavy carbon isotope. Methane withdrawn from the stems of five genera of rooted macrophysics ranging in latitude from the Florida Everglades to the Alaskan Arctic exhibited {sup 13}C enrichment relative to the sedimentary methane bubble reservoir. Several hypotheses based upon isotopic fractionation by methane transport, oxidation and production processes are proposed to explain this phenomenon.

Chanton, J. (Florida State Univ., Tallahassee (USA)); Crill, P. (Univ. of New Hampshire, Durham (USA)); Martens, C. (Univ. of North Carolina, Chapel Hill (USA)); Bartlett, K.

1989-08-01

422

Rabbits fed cholesterol-enriched diets exhibit pathological features of inclusion body myositis.  

PubMed

Sporadic inclusion body myositis (IBM) is the most common age-related muscle disease in humans; however, its etiology is unknown, there are few animal models for this disease, and effective treatments have not been identified. Similarities between pathological findings in Alzheimer'