XMM-Newton Observations of Solar Wind Charge Exchange Emission

NASA Technical Reports Server (NTRS)

Snowden, S. L.; Collier, M. R.; Kuntz, K. D.

2004-01-01

We present an XMM-Newton spectrum of diffuse X-ray emission from within the solar system. The spectrum is dominated by O VII and O VIII lines at 0.57 keV and 0.65 keV, O VIII (and possibly Fe XVII) lines at approximately 0.8 keV, Ne IX lines at approximately 0.92 keV, and Mg XI lines at approximately 1.35 keV. This spectrum is consistent with what is expected from charge exchange emission between the highly ionized solar wind and either interstellar neutrals in the heliosphere or material from Earth's exosphere. The emission is clearly seen as a low-energy ( E less than 1.5 keV) spectral enhancement in one of a series of observations of the Hubble Deep Field North. The X-ray enhancement is concurrent with an enhancement in the solar wind measured by the ACE satellite. The solar wind enhancement reaches a flux level an order of magnitude more intense than typical fluxes at 1 AU, and has ion ratios with significantly enhanced higher ionization states. Whereas observations of the solar wind plasma made at a single point reflect only local conditions which may only be representative of solar wind properties with spatial scales ranging from less than half of an Earth radii (approximately 10 s) to 100 Earth radii, X-ray observations of solar wind charge exchange are remote sensing measurements which may provide observations which are significantly more global in character. Besides being of interest in its own right for studies of the solar system, this emission can have significant consequences for observations of more cosmological objects. It can provide emission lines at zero redshift which are of particular interest (e.g., O VII and O VIII) in studies of diffuse thermal emission, and which can therefore act as contamination in objects which cover the entire detector field of view. We propose the use of solar wind monitoring data, such as from the ACE and Wind spacecraft, as a diagnostic to screen for such possibilities.

Charge exchange in galaxy clusters

NASA Astrophysics Data System (ADS)

Gu, Liyi; Mao, Junjie; de Plaa, Jelle; Raassen, A. J. J.; Shah, Chintan; Kaastra, Jelle S.

2018-03-01

Context. Though theoretically expected, the charge exchange emission from galaxy clusters has never been confidently detected. Accumulating hints were reported recently, including a rather marginal detection with the Hitomi data of the Perseus cluster. As previously suggested, a detection of charge exchange line emission from galaxy clusters would not only impact the interpretation of the newly discovered 3.5 keV line, but also open up a new research topic on the interaction between hot and cold matter in clusters. Aim. We aim to perform the most systematic search for the O VIII charge exchange line in cluster spectra using the RGS on board XMM-Newton. Methods: We introduce a sample of 21 clusters observed with the RGS. In order to search for O VIII charge exchange, the sample selection criterion is a >35σ detection of the O VIII Lyα line in the archival RGS spectra. The dominating thermal plasma emission is modeled and subtracted with a two-temperature thermal component, and the residuals are stacked for the line search. The systematic uncertainties in the fits are quantified by refitting the spectra with a varying continuum and line broadening. Results: By the residual stacking, we do find a hint of a line-like feature at 14.82 Å, the characteristic wavelength expected for oxygen charge exchange. This feature has a marginal significance of 2.8σ, and the average equivalent width is 2.5 × 10-4 keV. We further demonstrate that the putative feature can be barely affected by the systematic errors from continuum modeling and instrumental effects, or the atomic uncertainties of the neighboring thermal lines. Conclusions: Assuming a realistic temperature and abundance pattern, the physical model implied by the possible oxygen line agrees well with the theoretical model proposed previously to explain the reported 3.5 keV line. If the charge exchange source indeed exists, we expect that the oxygen abundance could have been overestimated by 8-22% in previous X-ray measurements that assumed pure thermal lines. These new RGS results bring us one step forward to understanding the charge exchange phenomenon in galaxy clusters.

Hidden crossing theory of charge exchange in H+ + He+(1 s) collisions in vicinity of maximum of cross section

NASA Astrophysics Data System (ADS)

Grozdanov, Tasko P.; Solov'ev, Evgeni A.

2018-04-01

Within the framework of dynamical adiabatic approach the hidden crossing theory of inelastic transitions is applied to charge exchange in H+ + He+(1 s) collisions in the wide range of center of mass collision energies E cm = (1.6 -70) keV. The good agreement with experiment and molecular close coupling calculations is obtained. At low energies our 4-state results are closest to the experiment and correctly reproduce the shoulder in energy dependence of the cross section around E cm = 6 keV. The 2-state results correctly predict the position of the maximum of the cross section at E cm ≈ 40 keV, whereas 4-state results fail to correctly describe the region around the maximum. The reason for this is the fact that adiabatic approximation for a given two-state hidden crossing is applicable for values of the Schtueckelberg parameter >1. But with increase of principal quantum number N the Schtueckelberg parameter decreases as N -3. That is why the 4-state approach involving higher excited states fails at smaller collision energies E cm ≈ 15 keV, while the 2-state approximation which involves low lying states can be extended to higher collision energies.

Induction of chromosomal aberrations at fluences of less than one HZE particle per cell nucleus.

PubMed

Hada, Megumi; Chappell, Lori J; Wang, Minli; George, Kerry A; Cucinotta, Francis A

2014-10-01

The assumption of a linear dose response used to describe the biological effects of high-LET radiation is fundamental in radiation protection methodologies. We investigated the dose response for chromosomal aberrations for exposures corresponding to less than one particle traversal per cell nucleus by high-energy charged (HZE) nuclei. Human fibroblast and lymphocyte cells were irradiated with several low doses of <0.1 Gy, and several higher doses of up to 1 Gy with oxygen (77 keV/μm), silicon (99 keV/μm) or Fe (175 keV/μm), Fe (195 keV/μm) or Fe (240 keV/μm) particles. Chromosomal aberrations at first mitosis were scored using fluorescence in situ hybridization (FISH) with chromosome specific paints for chromosomes 1, 2 and 4 and DAPI staining of background chromosomes. Nonlinear regression models were used to evaluate possible linear and nonlinear dose-response models based on these data. Dose responses for simple exchanges for human fibroblasts irradiated under confluent culture conditions were best fit by nonlinear models motivated by a nontargeted effect (NTE). The best fits for dose response data for human lymphocytes irradiated in blood tubes were a linear response model for all particles. Our results suggest that simple exchanges in normal human fibroblasts have an important NTE contribution at low-particle fluence. The current and prior experimental studies provide important evidence against the linear dose response assumption used in radiation protection for HZE particles and other high-LET radiation at the relevant range of low doses.

The Crossroads between the Galactic Disk and Interstellar Space, Ablaze in 3/4 keV Light

NASA Astrophysics Data System (ADS)

Shelton, Robin L.

2016-04-01

The halo is the crossroads between the Galactic disk and intergalactic space. This region is inhabited by hot gas that has risen from the disk, gas heated in situ, and hot material that has fallen in from intergalactic space. Owing to high spectral resolution observations made by by XMM-Newton, Suzaku, and Chandra of the hot plasma's 3/4 keV emission and absorption, increasingly sophisticated and CPU intensive computer modeling, and an awareness that charge exchange can contaminate 3/4 keV observations, we are now better able to understand the hot halo gas than ever before.Spectral analyses indicate that the 3/4 keV emission comes from T ~ 2.2 million Kelvin gas. Although observations suggest that the gas may be convectively unstable and the spectra's temperature is similar to that predicted by recent sophisticated models of the galactic fountain, the observed emission measure is significantly brighter than that predicted by fountain models. This brightness disparity presents us with another type of crossroads: should we continue down the road of adding physics to already sophisticated modeling or should we seek out other sources? In this presentation, I will discuss the galactic fountain crossroads, note the latitudinal and longitudinal distribution of the hot halo gas, provide an update on charge exchange, and explain how shadowing observations have helped to fine tune our understanding of the hot gas.

Analytical Data Report for Sediment Samples Collected From 116-KE-3 and UPR-100-K-1; Boreholes C8796 and C8796

DOE Office of Scientific and Technical Information (OSTI.GOV)

Snyder, Michelle M.V.; Last, George V.; Stephenson, John R.

2016-03-01

CH2M Hill Plateau Remediation Company (CHPRC) requested the services of the Pacific Northwest National Laboratory (PNNL) to perform contaminant leach testing on samples from two boreholes, C8796 and C8797, installed near the 105-KE reactor. These tests consisted of field texture column tests, <2 mm repacked column tests, batch desorption tests, and ion exchange experiments. In addition, hydraulic and physical property characterization was performed.

The Morphology of the X-ray Emission above 2 keV from Jupiter's Aurorae

NASA Technical Reports Server (NTRS)

Elsner, R.; Branduardi-Raymont, G.; Galand, M.; Grodent, D.; Gladstone, G. R.; Waite, J. H.; Cravens, T.; Ford, P.

2007-01-01

The discovery in XMM-Newton X-ray data of X-ray emission above 2 keY from Jupiter's aurorae has led us to reexamine the Chandra ACIS-S observations taken in Feb 2003. Chandra's superior spatial resolution has revealed that the auroral X-rays with E > 2 keV are emitted from the periphery of the region emitting those with E < 1 keV. We are presently exploring the relationship of this morphology to that of the FUV emission from the main auroral oval and the polar cap. The low energy emission has previously been established as due to charge exchange between energetic precipitating ions of oxygen and either sulfur or carbon. It seems likely to us that the higher energy emission is due to precipitation of energetic electrons, possibly the same population of electrons responsible for the FUV emission. We discuss our analysis and interpretation.

The Morphology of the X-ray Emission above 2 keV from Jupiter's Aurorae

NASA Technical Reports Server (NTRS)

Elsner, R.; Branduardi-Raymont, G.; Galand, M.; Grodent, D.; Waite, J. H.; Cravens, T.; Ford, P.

2007-01-01

The discovery in XMM-Newton X-ray data of X-ray emission above 2 keV from Jupiter's aurorae has led us to reexamine the Chandra ACIS-S observations taken in Feb 2003. Chandra's superior spatial resolution has revealed that the auroral X-rays with E > 2 keV are emitted from the periphery of the region emitting those with E < 1 keV. We are presently exploring the relationship of this morphology to that of the FUV emission from the main auroral oval and the polar cap. The low energy emission has previously been established as due to charge exchange between energetic precipitating ions of oxygen and either sulfur or carbon. It seems likely to us that the higher energy emission is due to precipitation of energetic electrons, possibly the same population of electrons responsible for the FUV emission. We discuss our analysis and interpretation.

Searching for the 3.5 keV Line in the Deep Fields with Chandra: The 10 Ms Observations

NASA Astrophysics Data System (ADS)

Cappelluti, Nico; Bulbul, Esra; Foster, Adam; Natarajan, Priyamvada; Urry, Megan C.; Bautz, Mark W.; Civano, Francesca; Miller, Eric; Smith, Randall K.

2018-02-01

We report a systematic search for an emission line around 3.5 keV in the spectrum of the cosmic X-ray background using a total of ∼10 Ms Chandra observations toward the COSMOS Legacy and Extended Chandra Deep Field South survey fields. We find marginal evidence of a feature at an energy of ∼3.51 keV with a significance of 2.5–3σ, depending on the choice of statistical treatment. The line intensity is best fit at (8.8 ± 2.9) × 10‑7 ph cm‑2 s‑1 when using a simple Δχ 2 or {10.2}-0.4+0.2× {10}-7 ph cm‑2 s‑1 when Markov chain Monte Carlo is used. Based on our knowledge of Chandra and the reported detection of the line by other instruments, an instrumental origin for the line remains unlikely. We cannot, however, rule out a statistical fluctuation, and in that case our results provide a 3σ upper limit at 1.85 × 10‑6 ph cm‑2 s‑1. We discuss the interpretation of this observed line in terms of the iron line background, S XVI charge exchange, as well as potentially being from sterile neutrino decay. We note that our detection is consistent with previous measurements of this line toward the Galactic center and can be modeled as the result of sterile neutrino decay from the Milky Way for the dark matter distribution modeled as a Navarro–Frenk–White profile. For this case, we estimate a mass m ν ∼ 7.01 keV and a mixing angle sin2(2θ) = (0.83–2.75) × 10‑10. These derived values are in agreement with independent estimates from galaxy clusters, the Galactic center, and M31.

Observed Limits on Charge Exchange Contributions to the Diffuse X-Ray Background

NASA Astrophysics Data System (ADS)

Crowder, S. G.; Barger, K. A.; Brandl, D. E.; Eckart, M. E.; Galeazzi, M.; Kelley, R. L.; Kilbourne, C. A.; McCammon, D.; Pfendner, C. G.; Porter, F. S.; Rocks, L.; Szymkowiak, A. E.; Teplin, I. M.

2012-10-01

We present a high-resolution spectrum of the diffuse X-ray background from 0.1 to 1 keV for a ~1 sr region of the sky centered at l = 90°, b = +60° using a 36 pixel array of microcalorimeters flown on a sounding rocket. With an energy resolution of 11 eV FWHM below 1 keV, the spectrum's observed line ratios help separate charge exchange contributions originating within the heliosphere from thermal emission of hot gas in the interstellar medium. The X-ray sensitivity below 1 keV was reduced by about a factor of four from contamination that occurred early in the flight, limiting the significance of the results. The observed centroid of helium-like O VII is 568+2 - 3 eV at 90% confidence. Since the centroid expected for thermal emission is 568.4 eV and for charge exchange is 564.2 eV, thermal emission appears to dominate for this line complex. The dominance of thermal emission is consistent with much of the high-latitude O VII emission originating in 2-3 × 106 K gas in the Galactic halo. On the other hand, the observed ratio of C VI Lyγ to Lyα is 0.3 ± 0.2. The expected ratios are 0.04 for thermal emission and 0.24 for charge exchange, indicating that charge exchange must contribute strongly to this line and therefore potentially to the rest of the ROSAT R12 band usually associated with 106 K emission from the Local Hot Bubble. The limited statistics of this experiment and systematic uncertainties due to the contamination require only >32% thermal emission for O VII and >20% from charge exchange for C VI at the 90% confidence level. An experimental gold coating on the silicon substrate of the array greatly reduced extraneous signals induced on nearby pixels from cosmic rays passing through the substrate, reducing the triggered event rate by a factor of 15 from a previous flight of the instrument.

Observed Limits on Charge Exchange Contributions to the Diffuse X-Ray Background

NASA Technical Reports Server (NTRS)

Crowder, S. G.; Barger, K. A.; Brandl, D. E.; Eckart, M. E.; Galeazzi, M.; Kelley, R. L.; Kilbourne, C. A.; McCammon, D.; Pfendner, C. G.; Porter, F. S.;

Exploring knowledge exchange: a useful framework for practice and policy.

PubMed

Ward, Vicky; Smith, Simon; House, Allan; Hamer, Susan

2012-02-01

Knowledge translation is underpinned by a dynamic and social knowledge exchange process but there are few descriptions of how this unfolds in practice settings. This has hampered attempts to produce realistic and useful models to help policymakers and researchers understand how knowledge exchange works. This paper reports the results of research which investigated the nature of knowledge exchange. We aimed to understand whether dynamic and fluid definitions of knowledge exchange are valid and to produce a realistic, descriptive framework of knowledge exchange. Our research was informed by a realist approach. We embedded a knowledge broker within three service delivery teams across a mental health organisation in the UK, each of whom was grappling with specific challenges. The knowledge broker participated in the team's problem-solving process and collected observational fieldnotes. We also interviewed the team members. Observational and interview data were analysed quantitatively and qualitatively in order to determine and describe the nature of the knowledge exchange process in more detail. This enabled us to refine our conceptual framework of knowledge exchange. We found that knowledge exchange can be understood as a dynamic and fluid process which incorporates distinct forms of knowledge from multiple sources. Quantitative analysis illustrated that five broadly-defined components of knowledge exchange (problem, context, knowledge, activities, use) can all be in play at any one time and do not occur in a set order. Qualitative analysis revealed a number of distinct themes which better described the nature of knowledge exchange. By shedding light on the nature of knowledge exchange, our findings problematise some of the linear, technicist approaches to knowledge translation. The revised model of knowledge exchange which we propose here could therefore help to reorient thinking about knowledge exchange and act as a starting point for further exploration and evaluation of the knowledge exchange process. Copyright © 2011 Elsevier Ltd. All rights reserved.

The Influence of Shielding on the Biological Effectiveness of Accelerated Particles for the Induction of Chromosome Damages

NASA Technical Reports Server (NTRS)

George, K.; Cucinotta, F. A.

2006-01-01

Chromosome damage was assessed in human peripheral blood lymphocytes after in vitro exposure to the either Si-28 (490 or 600 MeV/n), Ti-48 (1000 MeV/n), or Fe-56 (600, 1000, or 5000 MeV/n). LET values for these ions ranged from approximately 50 to 174 keV/micrometers and doses ranged from 10 to 200 cGy. The effect of either aluminum or polyethylene shielding on the induction of chromosome aberrations was investigated for each ion. Chromosome exchanges were measured using fluorescence in situ hybridization (FISH) with whole chromosome probes in cells collected 48-56 hours after irradiation using a chemical-induced premature chromosome condensation (PCC) technique. The yield of chromosomal aberrations increased linearly with dose and the relative biological effectiveness (RBE) for the primary beams, estimated from the initial slope of the dose response curve for total chromosomal exchanges with respect to gamma-rays, ranged from 14 to 35. The RBE values increased with LET, reaching a maximum for the 1 GeV/n Fe ions with LET of 150 keV/micrometers, and decreased with further increases in LET. When LET of the primary beam was in the region of increasing RBE (i.e. below approximately 100 keV/micrometers), the addition of shielding material increased the effectiveness per unit dose. Whereas shielding decreased the effectiveness per unit dose when the LET of the primary particle beam was higher than 150 keV/micrometers.

Separation of organic ion exchange resins from sludge -- engineering study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Duncan, J.B.

1998-08-25

This engineering study evaluates the use of physical separation technologies to separate organic ion exchange resin from KE Basin sludge prior to nitric acid dissolution. This separation is necessitate to prevent nitration of the organics in the acid dissolver. The technologies under consideration are: screening, sedimentation, elutriation. The recommended approach is to first screen the Sludge and resin 300 microns then subject the 300 microns plus material to elutriation.

The origin of the local 1/4-keV X-ray flux in both charge exchange and a hot bubble.

PubMed

Galeazzi, M; Chiao, M; Collier, M R; Cravens, T; Koutroumpa, D; Kuntz, K D; Lallement, R; Lepri, S T; McCammon, D; Morgan, K; Porter, F S; Robertson, I P; Snowden, S L; Thomas, N E; Uprety, Y; Ursino, E; Walsh, B M

2014-08-14

The solar neighbourhood is the closest and most easily studied sample of the Galactic interstellar medium, an understanding of which is essential for models of star formation and galaxy evolution. Observations of an unexpectedly intense diffuse flux of easily absorbed 1/4-kiloelectronvolt X-rays, coupled with the discovery that interstellar space within about a hundred parsecs of the Sun is almost completely devoid of cool absorbing gas, led to a picture of a 'local cavity' filled with X-ray-emitting hot gas, dubbed the local hot bubble. This model was recently challenged by suggestions that the emission could instead be readily produced within the Solar System by heavy solar-wind ions exchanging electrons with neutral H and He in interplanetary space, potentially removing the major piece of evidence for the local existence of million-degree gas within the Galactic disk. Here we report observations showing that the total solar-wind charge-exchange contribution is approximately 40 per cent of the 1/4-keV flux in the Galactic plane. The fact that the measured flux is not dominated by charge exchange supports the notion of a million-degree hot bubble extending about a hundred parsecs from the Sun.

Aviation Safety Risk Modeling: Lessons Learned From Multiple Knowledge Elicitation Sessions

NASA Technical Reports Server (NTRS)

Luxhoj, J. T.; Ancel, E.; Green, L. L.; Shih, A. T.; Jones, S. M.; Reveley, M. S.

2014-01-01

Aviation safety risk modeling has elements of both art and science. In a complex domain, such as the National Airspace System (NAS), it is essential that knowledge elicitation (KE) sessions with domain experts be performed to facilitate the making of plausible inferences about the possible impacts of future technologies and procedures. This study discusses lessons learned throughout the multiple KE sessions held with domain experts to construct probabilistic safety risk models for a Loss of Control Accident Framework (LOCAF), FLightdeck Automation Problems (FLAP), and Runway Incursion (RI) mishap scenarios. The intent of these safety risk models is to support a portfolio analysis of NASA's Aviation Safety Program (AvSP). These models use the flexible, probabilistic approach of Bayesian Belief Networks (BBNs) and influence diagrams to model the complex interactions of aviation system risk factors. Each KE session had a different set of experts with diverse expertise, such as pilot, air traffic controller, certification, and/or human factors knowledge that was elicited to construct a composite, systems-level risk model. There were numerous "lessons learned" from these KE sessions that deal with behavioral aggregation, conditional probability modeling, object-oriented construction, interpretation of the safety risk results, and model verification/validation that are presented in this paper.

Variational calculation of ground-state energy of iron atoms and condensed matter in strong magnetic fields. [at neutron star surfaces

NASA Technical Reports Server (NTRS)

Flowers, E. G.; Ruderman, M. A.; Lee, J.-F.; Sutherland, P. G.; Hillebrandt, W.; Mueller, E.

1977-01-01

Variational calculations of the binding energies of iron atoms and condensed matter in strong magnetic fields (greater than 10 to the 12th gauss). These calculations include the electron exchange energy. The cohesive energy of the condensed matter, which is the difference between these two binding energies, is of interest in pulsar theories and in the description of the surfaces of neutron stars. It is found that the cohesive energy ranges from 2.6 keV to 8.0 keV.

Numerical calculation of charge exchange cross sections for plasma diagnostics

NASA Astrophysics Data System (ADS)

Mendez, Luis

2016-09-01

The diagnostics of impurity density and temperature in the plasma core in tokamak plasmas is carried out by applying the charge exchange recombination spectroscopy (CXRS) technique, where a fast beam of H atoms collides with the plasma particles leading to electron capture reactions with the impurity ions. The diagnostics is based on the emission of the excited ions formed in the electron capture. The application of the CXRS requires the knowledge of accurate state-selective cross sections, which in general are not accessible experimentally, and the calculation of cross sections for the high n capture levels, required for the diagnostics in the intermediate energy domain of the probe beam, is particularly difficult. In this work, we present a lattice numerical method to solve the time dependent Schrödinger equation. The method is based on the GridTDSE package, it is applicable in the wide energy range 1 - 500 keV/u and can be used to assess the accuracy of previous calculations. The application of the method will be illustrated with calculations for collisions of multiply charged ions with H. Work partially supported by project ENE2014-52432-R (Secretaria de Estado de I+D+i, Spain).

Solar Wind Charge Exchange Studies Of Highly Charged Ions On Atomic Hydrogen

NASA Astrophysics Data System (ADS)

Draganić, I. N.; Seely, D. G.; McCammon, D.; Havener, C. C.

2011-06-01

Accurate studies of low-energy charge exchange (CX) are critical to understanding underlying soft X-ray radiation processes in the interaction of highly charged ions from the solar wind with the neutral atoms and molecules in the heliosphere, cometary comas, planetary atmospheres, interstellar winds, etc.. Particularly important are the CX cross sections for bare, H-like, and He-like ions of C, N, O and Ne, which are the dominant charge states for these heavier elements in the solar wind. Absolute total cross sections for single electron capture by H-like ions of C, N, O and fully-stripped O ions from atomic hydrogen have been measured in an expanded range of relative collision energies (5 eV/u-20 keV/u) and compared to previous H-oven measurements. The present measurements are performed using a merged-beams technique with intense highly charged ion beams extracted from a 14.5 GHz ECR ion source installed on a high voltage platform at the Oak Ridge National Laboratory. For the collision energy range of 0.3 keV/u-3.3 keV/u, which corresponds to typical ion velocities in the solar wind, the new measurements are in good agreement with previous H-oven measurements. The experimental results are discussed in detail and compared with theoretical calculations where available.

Knowledge exchange and integrated services: experiences from an integrated community intellectual (learning) disability service for adults.

PubMed

Farrington, C; Clare, I C H; Holland, A J; Barrett, M; Oborn, E

2015-03-01

This paper examines knowledge exchange dynamics in a specialist integrated intellectual (learning) disability service, comprising specialist healthcare provision with social care commissioning and management, and considers their significance in terms of integrated service delivery. A qualitative study focusing on knowledge exchange and integrated services. Semi-structured interviews (n = 25) were conducted with members of an integrated intellectual disability service in England regarding their perceptions of knowledge exchange within the service and the way in which knowledge exchange impinges on the operation of the integrated service. Exchange of 'explicit' (codifiable) knowledge between health and care management components of the service is problematic because of a lack of integrated clinical governance and related factors such as IT and care record systems and office arrangements. Team meetings and workplace interactions allowed for informal exchange of explicit and 'tacit' (non-codifiable) knowledge, but presented challenges in terms of knowledge exchange completeness and sustainability. Knowledge exchange processes play an important role in the functioning of integrated services incorporating health and care management components. Managers need to ensure that knowledge exchange processes facilitate both explicit and tacit knowledge exchange and do not rely excessively on informal, 'ad hoc' interactions. Research on integrated services should take account of micro-scale knowledge exchange dynamics and relationships between social dynamics and physical factors. © 2014 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

The Biological Effectiveness of Silicon Ions is Significantly Higher than Iron Ions for the Induction of Chromosome Damage in Human Lymphocytes

NASA Technical Reports Server (NTRS)

George, Kerry; Hada, Megumi; Cucinotta, F. A.

2010-01-01

Chromosome aberrations were measured in human peripheral blood lymphocytes after in vitro exposure to Si-28-ions with energies ranging from 90 to 600 MeV/u, or Fe-56-ions with energies ranging from 200 to 5,000 MeV/u. The LET of the various Fe beams in this study ranged from 145 to 440 keV/micron and the LET Si ions ranged from 48 to 158 keV/micron. Doses delivered were in the 10 to 200 cGy range. Dose response curves for chromosome exchanges in cells at first division after exposure, measured using fluorescence in situ hybridization (FISH) with whole chromosome probes, were fitted with linear or linear-quadratic functions. The relative biological effectiveness (RBE) was estimated from the initial slope of the dose response curve for chromosome damage with respect to gamma-rays. The estimates of RBE(sub max) values for total chromosome exchanges ranged from 4.4+/-0.4 to 31.5+/-2.6 for Fe ions, and 11.8+/-1.0 to 42.2+/-3.3 for Si ions. The highest RBE(sub max) value for Fe ions was obtained with the 600 Mev/u beam and 170 MeV/u beam produced the highest RBE(sub max) value for Si ions. For both ions the RBE(sub max) values increased with LET, reaching a maximum at about 180 keV/micron for Fe and about 100 keV/micron for Si, and decreased with further increase in LET.

The Influence of Shielding on the Biological Effectiveness of Accelerated Particles for the Induction of Chromosome Damage

NASA Technical Reports Server (NTRS)

Goeorge, Kerry; Cucinotta, Francis A.

2007-01-01

Chromosome damage was assessed in human peripheral blood lymphocytes after in vitro exposure to the either Si-28 (490 or 600 MeV/n), Ti-48 (1000 MeV/n), or Fe-56 (600, 1000, or 5000 MeV/n). LET values for these ions ranged from 51 to 184 keV/micron and doses ranged from 10 to 200 cGy. The effect of either aluminum or polyethylene shielding on the induction of chromosome aberrations was investigated for each ion. Chromosome exchanges were measured using fluorescence in situ hybridization (FISH) with whole chromosome probes in cells collected at G2 and mitosis in first division post irradiation after chromosomes were prematurely condensed using calyculin-A. The yield of chromosomal aberrations increased linearly with dose and the relative biological effectiveness (RBE) for the primary beams, estimated from the initial slope of the dose response curve for total chromosomal exchanges with respect to gamma-rays, ranged from 9 to 35. The RBE values increased with LET, reaching a maximum for the 600 MeV/n Fe ions with LET of 184 keV/micron. When the LET of the primary beam was below approximately 100 keV/micron, the addition of shielding material increased the effectiveness per unit dose. Whereas shielding decreased the effectiveness per unit dose when the LET of primary beams was higher than 100 keV/micron. The yield of aberrations correlated with the dose-average LET of the beam after traversal through the shielding.

The Biological Effectiveness of Different Radiation Qualities for the Induction of Chromosome Damage in Human Lymphocytes

NASA Technical Reports Server (NTRS)

Hada, M.; George, Kerry; Cucinotta, F. A.

2011-01-01

Chromosome aberrations were measured in human peripheral blood lymphocytes after in vitro exposure to Si-28-ions with energies ranging from 90 to 600 MeV/u, Ti-48-ions with energies ranging from 240 to 1000 MeV/u, or to Fe-56-ions with energies ranging from 200 to 5,000 MeV/u. The LET of the various Si beams in this study ranged from 48 to 158 keV/ m, the LET of the Ti ions ranged from 107 to 240 keV/micron, and the LET of the Fe-ions ranged from 145 to 440 keV/ m. Doses delivered were in the 10- to 200-cGy range. Dose-response curves for chromosome exchanges in cells at first division after exposure, measured using fluorescence in situ hybridization (FISH) with whole-chromosome probes, were fitted with linear or linear-quadratic functions. The relative biological effectiveness (RBE) was estimated from the initial slope of the dose-response curve for chromosome damage with respect to gamma-rays. The estimates of RBEmax values for total chromosome exchanges ranged from 4.4+/-0.4 to 31.5+/-2.6 for Fe ions, 21.4+/-1.7 to 28.3+/-2.4 for Ti ions, and 11.8+/-1.0 to 42.2+/-3.3 for Si ions. The highest RBEmax value for Fe ions was obtained with the 600 MeV/u beam, the highest RBEmax value for Ti ions was obtained 1000 MeV/u beam, and the highest RBEmax value for Si ions was obtained with the 170 MeV/u beam. For Si and Fe ions the RBEmax values increased with LET, reaching a maximum at about 180 keV/micron for Fe and about 100 keV/micron for Si, and decreasing with further increase in LET. Additional studies for low doses Si-28-ions down to 0.02 Gy will be discussed.

Induction of Chromosomal Aberrations at Fluences of Less Than One HZE Particle per Cell Nucleus

NASA Technical Reports Server (NTRS)

Hada, Megumi; Chappell, Lori J.; Wang, Minli; George, Kerry A.; Cucinotta, Francis A.

2014-01-01

The assumption of a linear dose response used to describe the biological effects of high LET radiation is fundamental in radiation protection methodologies. We investigated the dose response for chromosomal aberrations for exposures corresponding to less than one particle traversal per cell nucleus by high energy and charge (HZE) nuclei. Human fibroblast and lymphocyte cells where irradiated with several low doses of <0.1 Gy, and several higher doses of up to 1 Gy with O (77 keV/ (long-s)m), Si (99 keV/ (long-s)m), Fe (175 keV/ (long-s)m), Fe (195 keV/ (long-s)m) or Fe (240 keV/ (long-s)m) particles. Chromosomal aberrations at first mitosis were scored using fluorescence in situ hybridization (FISH) with chromosome specific paints for chromosomes 1, 2 and 4 and DAPI staining of background chromosomes. Non-linear regression models were used to evaluate possible linear and non-linear dose response models based on these data. Dose responses for simple exchanges for human fibroblast irradiated under confluent culture conditions were best fit by non-linear models motivated by a non-targeted effect (NTE). Best fits for the dose response data for human lymphocytes irradiated in blood tubes were a NTE model for O and a linear response model fit best for Si and Fe particles. Additional evidence for NTE were found in low dose experiments measuring gamma-H2AX foci, a marker of double strand breaks (DSB), and split-dose experiments with human fibroblasts. Our results suggest that simple exchanges in normal human fibroblasts have an important NTE contribution at low particle fluence. The current and prior experimental studies provide important evidence against the linear dose response assumption used in radiation protection for HZE particles and other high LET radiation at the relevant range of low doses.

A high resolution spectrum of the diffuse soft X-ray background

NASA Astrophysics Data System (ADS)

Crowder, S. Gwynne

Galactic contributions to the diffuse X-ray background were believed to largely come from thermal emission of hot gas and models of the Galactic neighborhood within ˜ 100 pc reflected this belief. However, recent observations led to the realization that emission from charge exchange within the Solar System might produce comparable intensities to that of thermal emission. A high resolution spectrum of the diffuse X-ray background from 0.1 to 1 keV was obtained for a ˜ 1 sr region of the sky centered at l = 90°, b = +60° in May 2008 using a 36 pixel array of microcalorimeters flown on a sounding rocket. With an energy resolution of 11 eV FWHM below 1 keV, the spectrum can be used to separate charge exchange contributions originating within the heliosphere from thermal emission of hot gas in the interstellar medium. The X-ray sensitivity below 1 keV was reduced about a factor of four by contamination that occurred early in the flight, limiting the significance of the results. The observed ratio of helium-like O VII forbidden plus intercombination to resonance lines is 1.2 +/- 1.2 at 90% confidence. This indicates that at least 67% of the emission is thermal. On the other hand, the observed ratio of C VI Lygamma to Lyalpha is 0.3+0.3-0.2 , requiring at least a 33% contribution from charge exchange. In addition to these astrophysical results, I present experimental improvements from the addition of a gold coating to the detector array substrate which greatly reduces extraneous signals and from the use of silicon support meshes which improves blocking filter robustness. I also detail a new optimal filtering analysis technique that preserves spectral resolution and live time in the presence of pulse overlap.

Knowledge Management in Doctoral Education toward Knowledge Economy

ERIC Educational Resources Information Center

Stamou, Adamantia

2017-01-01

Purpose: The purpose of this paper is to investigate the role and the scope of knowledge management (KM) in doctoral education, in the emerging knowledge economy (KE) context, and the recommendation of a framework for KM in doctoral education. Design/Methodology/Approach: An extended literature analysis was contacted to elaborate the role and the…

The Biological Effectiveness of Different Radiation Qualities for the Induction of Chromosome Damage in Human Lymphocytes

NASA Technical Reports Server (NTRS)

Hada, M.; George, K.; Cucinotta, F. A.

2010-01-01

Chromosome aberrations were measured in human peripheral blood lymphocytes after in vitro exposure to 28Si- ions with energies ranging from 90 to 600 MeV/u, or to 56Fe-ions with energies ranging from 200 to 5,000 MeV/u. The LET of the various Fe beams in this study ranged from 145 to 440 keV/micron and the LET of the Si ions ranged from 48 to 158 keV/ m. Doses delivered were in the 10- to 200-cGy range. Dose-response curves for chromosome exchanges in cells at first division after exposure, measured using fluorescence in situ hybridization (FISH) with whole-chromosome probes, were fitted with linear or linear-quadratic functions. The relative biological effectiveness (RBE) was estimated from the initial slope of the dose-response curve for chromosome damage with respect to -rays. The estimates of RBE(sub max) values for total chromosome exchanges ranged from 4.4+/-0.4 to 31.5+/-2.6 for Fe ions, and 11.8+/-1.0 to 42.2+/-3.3 for Si ions. The highest RBE(sub max) value for Fe ions was obtained with the 600-Mev/u beam, and the highest RBE(sub max) value for Si ions was obtained with the 170 MeV/u beam. For both ions the RBEmax values increased with LET, reaching a maximum at about 180 keV/micron for Fe and about 100 keV/ m for Si, and decreasing with further increase in LET. Additional studies for low doses 28Si-ions down to 0.02 Gy will be discussed.

The loss rates of O+ in the inner magnetosphere caused by both magnetic field line curvature scattering and charge exchange reactions

NASA Astrophysics Data System (ADS)

Ji, Y.; Shen, C.

2014-03-01

With consideration of magnetic field line curvature (FLC) pitch angle scattering and charge exchange reactions, the O+ (>300 keV) in the inner magnetosphere loss rates are investigated by using an eigenfunction analysis. The FLC scattering provides a mechanism for the ring current O+ to enter the loss cone and influence the loss rates caused by charge exchange reactions. Assuming that the pitch angle change is small for each scattering event, the diffusion equation including a charge exchange term is constructed and solved; the eigenvalues of the equation are identified. The resultant loss rates of O+ are approximately equal to the linear superposition of the loss rate without considering the charge exchange reactions and the loss rate associated with charge exchange reactions alone. The loss time is consistent with the observations from the early recovery phases of magnetic storms.

Estimate of the frequency of true incomplete exchanges in human lymphocytes exposed to 1 GeV/u Fe ions in vitro

NASA Technical Reports Server (NTRS)

Wu, H.; George, K.; Yang, T. C.

1999-01-01

PURPOSE: To study the frequency of true incomplete exchanges induced by high-LET radiation. MATERIALS AND METHODS: Human lymphocytes were exposed to 1 GeV/u Fe ions (LET = 140 keV/microm). Chromosome aberrations were analysed by a fluorescence in situ hybridization using a combination of whole-chromosome-specific probes and human telomere probes. Chromosomes 1, 3 and 4 were investigated. RESULTS: The percentage of incomplete exchanges was between 23 and 29% if telomere signals were not considered. The percentage decreased to approximately 10% after ruling out false incomplete exchanges containing telomere signals. The final estimation of true incomplete exchanges was <10%. CONCLUSION: Within a degree of uncertainty, the percentage of true incomplete exchanges in 1 GeV/u Fe ion-irradiated human lymphocytes was similar to that induced by gamma rays.

Knowledge exchange systems for youth health and chronic disease prevention: a tri-provincial case study.

PubMed

Murnaghan, D; Morrison, W; Griffith, E J; Bell, B L; Duffley, L A; McGarry, K; Manske, S

2013-09-01

The research teams undertook a case study design using a common analytical framework to investigate three provincial (Prince Edward Island, New Brunswick and Manitoba) knowledge exchange systems. These three knowledge exchange systems seek to generate and enhance the use of evidence in policy development, program planning and evaluation to improve youth health and chronic disease prevention. We applied a case study design to explore the lessons learned, that is, key conditions or processes contributing to the development of knowledge exchange capacity, using a multi-data collection method to gain an in-depth understanding. Data management, synthesis and analysis activities were concurrent, iterative and ongoing. The lessons learned were organized into seven "clusters." Key findings demonstrated that knowledge exchange is a complex process requiring champions, collaborative partnerships, regional readiness and the adaptation of knowledge exchange to diverse stakeholders. Overall, knowledge exchange systems can increase the capacity to exchange and use evidence by moving beyond collecting and reporting data. Areas of influence included development of new partnerships, expanded knowledge-sharing activities, and refinement of policy and practice approaches related to youth health and chronic disease prevention.

Can knowledge exchange support the implementation of a health-promoting schools approach? Perceived outcomes of knowledge exchange in the COMPASS study.

PubMed

Brown, Kristin M; Elliott, Susan J; Robertson-Wilson, Jennifer; Vine, Michelle M; Leatherdale, Scott T

2018-03-13

Despite the potential population-level impact of a health-promoting schools approach, schools face challenges in implementation, indicating a gap between school health research and practice. Knowledge exchange provides an opportunity to reduce this gap; however, there has been limited evaluation of these initiatives. This research explored researchers' and knowledge users' perceptions of outcomes associated with a knowledge exchange initiative within COMPASS, a longitudinal study of Canadian secondary students and schools. Schools received annual tailored summaries of their students' health behaviours and suggestions for action and were linked with knowledge brokers to support them in taking action to improve student health. Qualitative semi-structured interviews were conducted with COMPASS researchers (n = 13), school staff (n = 13), and public health stakeholders (n = 4) to explore their experiences with COMPASS knowledge exchange. Key issues included how knowledge users used school-specific findings, perceived outcomes of knowledge exchange, and suggestions for change. Outcomes for both knowledge users and researchers were identified; interestingly, knowledge users attributed more outcomes to using school-specific findings than knowledge brokering. School and public health participants indicated school-specific findings informed their programming and planning. Importantly, knowledge exchange provided a platform for partnerships between researchers, schools, and public health units. Knowledge brokering allowed researchers to gain feedback from knowledge users to enhance the study and a better understanding of the school environment. Interestingly, COMPASS knowledge exchange outcomes aligned with Samdal and Rowling's eight theory-driven implementation components for health-promoting schools. Hence, knowledge exchange may provide a mechanism to help schools implement a health-promoting schools approach. This research contributes to the limited literature regarding outcomes of knowledge brokering in public health and knowledge exchange in school health research. However, since not all schools engaged in knowledge brokering, and not all schools that engaged discussed these outcomes, further research is needed to determine the amount of engagement required for change and examine the process of COMPASS knowledge brokering to consider how to increase school engagement.

The Structure of the Local Hot Bubble

NASA Technical Reports Server (NTRS)

Liu, W.; Chiao, M.; Collier, M. R.; Cravens, T.; Galeazzi, M.; Koutroumpa, D.; Kuntz, K. D.; Lallement, R.; Lepri, S. T.; McCammon, Dan;

Modified Fourth-Order Kinetic Energy Gradient Expansion with Hartree Potential-Dependent Coefficients.

PubMed

Constantin, Lucian A; Fabiano, Eduardo; Della Sala, Fabio

2017-09-12

Using the semiclassical neutral atom theory, we developed a modified fourth-order kinetic energy (KE) gradient expansion (GE4m) that keeps unchanged all the linear-response terms of the uniform electron gas and gives a significant improvement with respect to the known semilocal functionals for both large atoms and jellium surfaces. On the other hand, GE4m is not accurate for light atoms; thus, we modified the GE4m coefficients making them dependent on a novel ingredient, the reduced Hartree potential, recently introduced in the Journal of Chemical Physics 2016, 145, 084110, in the context of exchange functionals. The resulting KE gradient expansion functional, named uGE4m, belongs to the novel class of u-meta-generalized-gradient-approximations (uMGGA) whose members depend on the conventional ingredients (i.e., the reduced gradient and Laplacian of the density) as well as on the reduced Hartree potential. To test uGE4m, we defined an appropriate benchmark (including total KE and KE differences for atoms, molecules and jellium clusters) for gradient expansion functionals, that is, including only those systems which are mainly described by a slowly varying density regime. While most of the GGA and meta-GGA KE functionals (we tested 18 of them) are accurate for some properties and inaccurate for others, uGE4m shows a consistently good performance for all the properties considered. This represents a qualitative boost in the KE functional development and highlights the importance of the reduced Hartree potential for the construction of next-generation KE functionals.

The Evolution of the Plasma Sheet Ion Composition: Storms and Recoveries: Plasma Sheet Ion Composition

DOE PAGES

Denton, M. H.; Thomsen, M. F.; Reeves, G. D.; ...

2017-10-03

The ion plasma sheet (~few hundred eV to ~few 10s keV) is usually dominated by H + ions. Here, changes in ion composition within the plasma sheet are explored both during individual events, and statistically during 54 calm-to-storm events and during 21 active-to-calm events. Ion composition data from the HOPE (Helium, Oxygen, Proton, Electron) instruments onboard Van Allen Probes satellites provide exceptional spatial and temporal resolution of the H +, O +, and He + ion fluxes in the plasma sheet. H+ shown to be the dominant ion in the plasma sheet in the calm-to-storm transition. However, the energy-flux ofmore » each ion changes in a quasi-linear manner during extended calm intervals. Heavy ions (O + and He +) become increasingly important during such periods as charge-exchange reactions result in faster loss for H + than for O + or He +. Results confirm previous investigations showing that the ion composition of the plasma sheet can be largely understood (and predicted) during calm intervals from knowledge of: (a) the composition of previously injected plasma at the onset of calm conditions, and (b) use of simple drift-physics models combined with calculations of charge-exchange losses.« less

The Evolution of the Plasma Sheet Ion Composition: Storms and Recoveries: Plasma Sheet Ion Composition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Denton, M. H.; Thomsen, M. F.; Reeves, G. D.

The ion plasma sheet (~few hundred eV to ~few 10s keV) is usually dominated by H + ions. Here, changes in ion composition within the plasma sheet are explored both during individual events, and statistically during 54 calm-to-storm events and during 21 active-to-calm events. Ion composition data from the HOPE (Helium, Oxygen, Proton, Electron) instruments onboard Van Allen Probes satellites provide exceptional spatial and temporal resolution of the H +, O +, and He + ion fluxes in the plasma sheet. H+ shown to be the dominant ion in the plasma sheet in the calm-to-storm transition. However, the energy-flux ofmore » each ion changes in a quasi-linear manner during extended calm intervals. Heavy ions (O + and He +) become increasingly important during such periods as charge-exchange reactions result in faster loss for H + than for O + or He +. Results confirm previous investigations showing that the ion composition of the plasma sheet can be largely understood (and predicted) during calm intervals from knowledge of: (a) the composition of previously injected plasma at the onset of calm conditions, and (b) use of simple drift-physics models combined with calculations of charge-exchange losses.« less

The Origin of the Local 1/4-KeV X-Ray Flux in Both Charge Exhange and a Hot Bubble

NASA Technical Reports Server (NTRS)

Galeazzi, M.; Chiao, M.; Collier, M. R.; Cravens, T.; Koutroumpa, D.; Kuntz, K. D.; Lallement, R.; Lepri, S. T.; McCammon, D.; Morgan, K.;

"I Ulu No Ka Lala I Ke Kumu", The Branches Grow Because of the Trunk: Ancestral Knowledge as Refusal

ERIC Educational Resources Information Center

Chandler, Kapua L.

2018-01-01

This paper will discuss the ways that Native Hawaiian scholars are engaging in innovative strategies that incorporate ancestral knowledges into the academy. Ancestral knowledges are highly valued as Indigenous communities strive to pass on such wisdom and lessons from generation to generation. Ancestral knowledges are all around us no matter where…

Contraction velocity influence the magnitude and etiology of neuromuscular fatigue during repeated maximal contractions.

PubMed

Morel, B; Clémençon, M; Rota, S; Millet, G Y; Bishop, D J; Brosseau, O; Rouffet, D M; Hautier, C A

2015-10-01

This study aimed to compare the magnitude and etiology of neuromuscular fatigue during maximal repeated contractions performed in two contraction modes (concentric vs isometric) and at two contraction velocities (30/s vs 240°/s). Eleven lower limb-trained males performed 20 sets of maximal contractions at three different angular velocities: 0°/s (KE0), 30/s (KE30), and 240°/s (KE240). Cumulated work, number of contraction, duty cycle, and contraction time were controlled. Torque, superimposed and resting twitches, as well as gas exchange, were analyzed. Increasing contraction velocity was associated with greater maximal voluntary torque loss (KE0: -9.8 ± 3.9%; KE30: -16.4 ± 8.5%; KE240: -32.6 ± 6.3%; P < 0.05). Interestingly, the torque decrease was similar for a given cumulated work. Compared with KE0, KE240 generated a greater evoked torque loss (Db100: -24.3 ± 5.3% vs -5.9 ± 6.9%; P < 0.001), a higher O2 consumption (23.7 ± 6.4 mL/min/kg vs 15.7 ± 3.8 mL/min/kg; P < 0.001), but a lower voluntary activation (VA) loss (-4.3 ± 1.6% vs -11.2 ± 4.9%; P < 0.001). The neuromuscular perturbations were intermediate for KE30 (Db100: -10.0 ± 6.8%; VA: -7.2 ± 2.8%). Although the amount of mechanical work cumulated strongly determined the magnitude of torque decrease, the contraction velocity and mode influenced the origin of the neuromuscular fatigue. The metabolic stress and peripheral fatigue increased but reduction of VA is attenuated when the contraction velocity increased from 0°/s to 240°/s. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Knowledge Exchange in the Shrines of Knowledge: The ''How's'' and ''Where's'' of Knowledge Sharing Processes

ERIC Educational Resources Information Center

Reychav, Iris; Te'eni, Dov

2009-01-01

Academic conferences are places of situated learning dedicated to the exchange of knowledge. Knowledge is exchanged between colleagues who are looking to enhance their future research by taking part in several formal and informal settings (lectures, discussions and social events). We studied the processes of knowledge sharing and the influence of…

In vivo and in vitro measurements of complex-type chromosomal exchanges induced by heavy ions.

PubMed

George, K; Durante, M; Wu, H; Willingham, V; Cucinotta, F A

2003-01-01

Heavy ions are more efficient in producing complex-type chromosome exchanges than sparsely ionizing radiation, and this can potentially be used as a biomarker of radiation quality. We measured the induction of complex-type chromosomal aberrations in human peripheral blood lymphocytes exposed in vitro to accelerated H-, He-, C-, Ar-, Fe- and Au-ions in the LET range of approximately 0.4-1400 keV/micrometers. Chromosomes were analyzed either at the first post-irradiation mitosis, or in interphase, following premature condensation by phosphatase inhibitors. Selected chromosomes were then visualized after FISH-painting. The dose-response curve for the induction of complex-type exchanges by heavy ions was linear in the dose-range 0.2-1.5 Gy, while gamma-rays did not produce a significant increase in the yield of complex rearrangements in this dose range. The yield of complex aberrations after 1 Gy of heavy ions increased up to an LET around 100 keV/micrometers, and then declined at higher LET values. When mitotic cells were analyzed, the frequency of complex rearrangements after 1 Gy was about 10 times higher for Ar- or Fe- ions (the most effective ions, with LET around 100 keV/micrometers) than for 250 MeV protons, and values were about 35 times higher in prematurely condensed chromosomes. These results suggest that complex rearrangements may be detected in astronauts' blood lymphocytes after long-term space flight, because crews are exposed to HZE particles from galactic cosmic radiation. However, in a cytogenetic study of ten astronauts after long-term missions on the Mir or International Space Station, we found a very low frequency of complex rearrangements, and a significant post-flight increase was detected in only one out of the ten crewmembers. It appears that the use of complex-type exchanges as biomarker of radiation quality in vivo after low-dose chronic exposure in mixed radiation fields is hampered by statistical uncertainties. c2003 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

Vacuum system design and tritium inventory for the TFTR charge exchange diagnostic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Medley, S.S.

The charge exchange diagnostic for the TFTR is comprised of two analyzer systems which contain a total of twenty independent mass/energy analyzers and one diagnostic neutral beam tentatively rated at 80 keV, 15 A. The associated vacuum systems were analyzed using the Vacuum System Transient Simulator (VSTS) computer program which models the transient transport of multi-gas species through complex networks of ducts, valves, traps, vacuum pumps, and other related vacuum system components. In addition to providing improved design performance at reduced cost, the analysis yields estimates for the exchange of tritium from the torus to the diagnostic components and ofmore » the diagnostic working gases to the torus.« less

From science to action: Principles for undertaking environmental research that enables knowledge exchange and evidence-based decision-making.

PubMed

Cvitanovic, C; McDonald, J; Hobday, A J

2016-12-01

Effective conservation requires knowledge exchange among scientists and decision-makers to enable learning and support evidence-based decision-making. Efforts to improve knowledge exchange have been hindered by a paucity of empirically-grounded guidance to help scientists and practitioners design and implement research programs that actively facilitate knowledge exchange. To address this, we evaluated the Ningaloo Research Program (NRP), which was designed to generate new scientific knowledge to support evidence-based decisions about the management of the Ningaloo Marine Park in north-western Australia. Specifically, we evaluated (1) outcomes of the NRP, including the extent to which new knowledge informed management decisions; (2) the barriers that prevented knowledge exchange among scientists and managers; (3) the key requirements for improving knowledge exchange processes in the future; and (4) the core capacities that are required to support knowledge exchange processes. While the NRP generated expansive and multidisciplinary science outputs directly relevant to the management of the Ningaloo Marine Park, decision-makers are largely unaware of this knowledge and little has been integrated into decision-making processes. A range of barriers prevented efficient and effective knowledge exchange among scientists and decision-makers including cultural differences among the groups, institutional barriers within decision-making agencies, scientific outputs that were not translated for decision-makers and poor alignment between research design and actual knowledge needs. We identify a set of principles to be implemented routinely as part of any applied research program, including; (i) stakeholder mapping prior to the commencement of research programs to identify all stakeholders, (ii) research questions to be co-developed with stakeholders, (iii) implementation of participatory research approaches, (iv) use of a knowledge broker, and (v) tailored knowledge management systems. Finally, we articulate the individual, institutional and financial capacities that must be developed to underpin successful knowledge exchange strategies. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Energetic Neutral Atom Spectra in the 0.2-3.0 keV from a Residual Source Across the Sky Obtained by the Neutral Particle Detector on board Venus Express

NASA Astrophysics Data System (ADS)

Brandt, Pontus; Roelof, Edmond; Wurz, Peter; Decker, Robert; Barabash, Stas; Bazell, David; Sotirelis, Thomas

We have surveyed the sky for residual energetic neutral atom (ENA) signals in the energy range of 0.2-3.0 keV [Brandt et al., AIP Proceedings, 2009]. Approximately three years of data obtained by the Neutral Particle Detector (NPD) on board Venus Express (VEX) from May 2006 through August 2009 have been analyzed. After applying strict viewing criteria to minimize all known signals and subtracting the UV background from the Milky Way, we find a residual energy spectral shape with a ledge/bump at around 0.5 keV and a break in the spectral slope at about 1.0 keV, reiminiscent of the spectral shape obtained in reverse shocks. The ledge/bump at about 0.5 keV appears consistent with twice the plasma flow velocity obtained by the V1 measurements in the inner HS. When the ENA spectrum is divided by the energy dependent charge exchange cross section its slope above 1 keV has a spectral power-law index of 1.5, with some variations across the sky. In order to better understand the spectral shape over an extended energy range we compare the spectra obtained by VEX/NPD with the ones reported by the Interstellar Boundary Explorer (IBEX) [Funsten et al., Science, 2009], by the Ion Neutral Camera (INCA) on board Cassini [Krimigis et al., Science, 2009]and with those measured in-situ in the inner heliosheath (HS) by the Low-Energy Charged Particle (LECP) instrument (>40 keV) on board Voyager-1 (V1).

Quick-EXAFS setup at the SuperXAS beamline for in situ X-ray absorption spectroscopy with 10 ms time resolution

PubMed Central

Müller, Oliver; Nachtegaal, Maarten; Just, Justus; Lützenkirchen-Hecht, Dirk; Frahm, Ronald

2016-01-01

The quick-EXAFS (QEXAFS) method adds time resolution to X-ray absorption spectroscopy (XAS) and allows dynamic structural changes to be followed. A completely new QEXAFS setup consisting of monochromator, detectors and data acquisition system is presented, as installed at the SuperXAS bending-magnet beamline at the Swiss Light Source (Paul Scherrer Institute, Switzerland). The monochromator uses Si(111) and Si(311) channel-cut crystals mounted on one crystal stage, and remote exchange allows an energy range from 4.0 keV to 32 keV to be covered. The spectral scan range can be electronically adjusted up to several keV to cover multiple absorption edges in one scan. The determination of the Bragg angle close to the position of the crystals allows high-accuracy measurements. Absorption spectra can be acquired with fast gridded ionization chambers at oscillation frequencies of up to 50 Hz resulting in a time resolution of 10 ms, using both scan directions of each oscillation period. The carefully developed low-noise detector system yields high-quality absorption data. The unique setup allows both state-of-the-art QEXAFS and stable step-scan operation without the need to exchange whole monochromators. The long-term stability of the Bragg angle was investigated and absorption spectra of reference materials as well as of a fast chemical reaction demonstrate the overall capabilities of the new setup. PMID:26698072

Quick-EXAFS setup at the SuperXAS beamline for in situ X-ray absorption spectroscopy with 10 ms time resolution.

PubMed

Müller, Oliver; Nachtegaal, Maarten; Just, Justus; Lützenkirchen-Hecht, Dirk; Frahm, Ronald

2016-01-01

The quick-EXAFS (QEXAFS) method adds time resolution to X-ray absorption spectroscopy (XAS) and allows dynamic structural changes to be followed. A completely new QEXAFS setup consisting of monochromator, detectors and data acquisition system is presented, as installed at the SuperXAS bending-magnet beamline at the Swiss Light Source (Paul Scherrer Institute, Switzerland). The monochromator uses Si(111) and Si(311) channel-cut crystals mounted on one crystal stage, and remote exchange allows an energy range from 4.0 keV to 32 keV to be covered. The spectral scan range can be electronically adjusted up to several keV to cover multiple absorption edges in one scan. The determination of the Bragg angle close to the position of the crystals allows high-accuracy measurements. Absorption spectra can be acquired with fast gridded ionization chambers at oscillation frequencies of up to 50 Hz resulting in a time resolution of 10 ms, using both scan directions of each oscillation period. The carefully developed low-noise detector system yields high-quality absorption data. The unique setup allows both state-of-the-art QEXAFS and stable step-scan operation without the need to exchange whole monochromators. The long-term stability of the Bragg angle was investigated and absorption spectra of reference materials as well as of a fast chemical reaction demonstrate the overall capabilities of the new setup.

Exploring knowledge exchange at the research-policy-practice interface in children's behavioral health services.

PubMed

Leslie, Laurel K; Maciolek, Susan; Biebel, Kathleen; Debordes-Jackson, Gifty; Nicholson, Joanne

2014-11-01

This case study explored core components of knowledge exchange among researchers, policymakers, and practitioners within the context of the Rosie D. versus Romney class action lawsuit in Massachusetts and the development and implementation of its remedial plan. We identified three distinct, sequential knowledge exchange episodes with different purposes, stakeholders, and knowledge exchanged, as decision-making moved from Federal Medicaid policy to state Medicaid program standards and to community-level practice. The knowledge exchanged included research regarding Wraparound, a key component of the remedial plan, as well as contextual information critical for implementation (e.g., Federal Medicaid policy, managed care requirements, community organizations' characteristics).

Heavy-ion dominance near Cluster perigees

NASA Astrophysics Data System (ADS)

Ferradas, C. P.; Zhang, J.-C.; Kistler, L. M.; Spence, H. E.

2015-12-01

Time periods in which heavy ions dominate over H+ in the energy range of 1-40 keV were observed by the Cluster Ion Spectrometry (CIS)/COmposition DIstribution Function (CODIF) instrument onboard Cluster Spacecraft 4 at L values less than 4. The characteristic feature is a narrow flux peak at around 10 keV that extends into low L values, with He+ and/or O+ dominating. In the present work we perform a statistical study of these events and examine their temporal occurrence and spatial distribution. The observed features, both the narrow energy range and the heavy-ion dominance, can be interpreted using a model of ion drift from the plasma sheet, subject to charge exchange losses. The narrow energy range corresponds to the only energy range that has direct drift access from the plasma sheet during quiet times. The drift time to these locations from the plasma sheet is > 30 h, so that charge exchange has a significant impact on the population. We show that a simple drift/loss model can explain the dependence on L shell and MLT of these heavy-ion-dominant time periods.

Study of inelastic processes in Li+-Ar, K+-Ar, and Na+-He collisions in the energy range 0.5-10 keV

NASA Astrophysics Data System (ADS)

Lomsadze, Ramaz A.; Gochitashvili, Malkhaz R.; Kezerashvili, Roman Ya; Schulz, Michael

2017-11-01

Absolute cross sections are measured for charge-exchange, ionization, and excitation processes within the same experimental setup for the Li{}+-Ar, K{}+-Ar, and Na{}+-He collisions in the ion energy range of 0.5-10 keV. The results of the measurements and schematic correlation diagrams are used to analyze and determine the mechanisms for these processes. The experimental results show that the charge-exchange processes occur with high probabilities and electrons are predominantly captured in ground states. The contributions of various partial inelastic channels to the total ionization cross section are estimated, and a primary mechanism for the process is identified. In addition, the energy-loss spectrum is applied in order to estimate the relative contribution of different inelastic channels, and to determine the mechanisms for the ionization and for some excitation processes of Ar resonance lines for the {{{K}}}+-Ar collision system. The excitation cross sections for the helium and for the sodium doublet lines for the Na{}+-He collision system both reveal some unexpected features. A mechanism to explain this observation is suggested.

Decreased Diastolic Ventricular Kinetic Energy in Young Patients with Fontan Circulation Demonstrated by Four-Dimensional Cardiac Magnetic Resonance Imaging.

PubMed

Sjöberg, Pia; Heiberg, Einar; Wingren, Pär; Ramgren Johansson, Jens; Malm, Torsten; Arheden, Håkan; Liuba, Petru; Carlsson, Marcus

2017-04-01

Four-dimensional (4D) flow magnetic resonance imaging (MRI) enables quantification of kinetic energy (KE) in intraventricular blood flow. This provides a novel way to understand the cardiovascular physiology of the Fontan circulation. In this study, we aimed to quantify the KE in functional single ventricles. 4D flow MRI was acquired in eleven patients with Fontan circulation (median age 12 years, range 3-29) and eight healthy volunteers (median age 26 years, range 23-36). Follow-up MRI after surgical or percutaneous intervention was performed in 3 patients. Intraventricular KE was calculated throughout the cardiac cycle and indexed to stroke volume (SV). The systolic/diastolic ratio of KE in Fontan patients was similar to the ratio of the controls' left ventricle (LV) or right ventricle (RV) depending on the patients' ventricular morphology (Cohen´s κ = 1.0). Peak systolic KE/SV did not differ in patients compared to the LV in controls (0.016 ± 0.006 mJ/ml vs 0.020 ± 0.004 mJ/ml, p = 0.09). Peak diastolic KE/SV in Fontan patients was lower than in the LV of the control group (0.028 ± 0.010 mJ/ml vs 0.057 ± 0.011 mJ/ml, p < 0.0001). The KE during diastole showed a plateau in patients with aortopulmonary collaterals. This is to our knowledge the first study that quantifies the intraventricular KE of Fontan patients. KE is dependent on the morphology of the ventricle, and diastolic KE indexed to SV in patients is decreased compared to controls. The lower KE in Fontan patients may be a result of impaired ventricular filling.

Tailoring the structural and magnetic properties of masked CoPt thin films using ion implantation

NASA Astrophysics Data System (ADS)

Kumar, Durgesh; Gupta, Surbhi; Jin, Tianli; Nongjai, R.; Asokan, K.; Piramanayagam, S. N.

2018-05-01

The effects of ion implantations through a mask on the structural and magnetic properties of Co80Pt20 films were investigated. The mask was patterned using the self-assembly of diblock copolymers. For implantation, high (40 keV for 14N+ and 100 keV for 40Ar+) and low (7.5 keV for 14N+ and 4.5 keV for 40Ar+) energy 14N+ and 40Ar+ ions were used to modify the structural and magnetic properties of these films. X-ray diffraction and TRIM simulations were performed for understanding the structural changes due to ion implantations. These results revealed the intermixing of Co atoms in lower layers and lattice expansion in Co80Pt20 magnetic and Ru layers. A lateral straggling of Co caused an increase in the exchange coupling in the masked region. Depletion of Co atoms in Co80Pt20 layer caused a decrease in the anisotropy constant, which were further confirmed by the alternating gradient force magnetometer and magnetic force microscopy results. The magnetic force microscopy images showed an increase in domain width and domain wall width confirming the above-mentioned effects.

SERENA: A Neutral Atoms Detector to be proposed for the ESA's BepiColombo Planetary Orbiter

NASA Astrophysics Data System (ADS)

di Lellis, A.; Orsini, S.; Livi, S.; Wurz, P.; Milillo, A.; Barabash, S.

2003-04-01

A comprehensive suite for the neutral particles detection in the Mercury environment is under development and it will be proposed in the frame of the ESA cornerstone’s BepiColombo mission. The package, namely NPA - SERENA (Neutral Particle Analyser - Searching for Exospheric Refilling and Emitted Neutral Abundances), consists of three dedicated spectrometers (MAIA, ELENA, and M/H-ENA) identifying and measuring the particles and their energies, namely from fraction of eV to tens of keV. The proposed sensors will observe and analyse the bulk of the sub-thermal / thermal exospheric (0-50 eV) gas along the ram direction (MAIA), the sputtering emission (E min < 100eV; E max > 1 keV) within 1-D (2 deg x 60 deg) nadir cross track slices from the planet surface (ELENA), and the charge exchange between ions and exospheric gas (E min < 5 keV; E max > 30 keV) in order to monitor the Mercury’s magnetosphere dynamics (M/H-ENA). The paper describes the progress achieved in the system and sensor level design and provides a summary report on the laboratory test of the investigated techniques and of the expected performances of the ELENA detector head.

Key exchange using biometric identity based encryption for sharing encrypted data in cloud environment

NASA Astrophysics Data System (ADS)

Hassan, Waleed K.; Al-Assam, Hisham

2017-05-01

The main problem associated with using symmetric/ asymmetric keys is how to securely store and exchange the keys between the parties over open networks particularly in the open environment such as cloud computing. Public Key Infrastructure (PKI) have been providing a practical solution for session key exchange for loads of web services. The key limitation of PKI solution is not only the need for a trusted third partly (e.g. certificate authority) but also the absent link between data owner and the encryption keys. The latter is arguably more important where accessing data needs to be linked with identify of the owner. Currently available key exchange protocols depend on using trusted couriers or secure channels, which can be subject to man-in-the-middle attack and various other attacks. This paper proposes a new protocol for Key Exchange using Biometric Identity Based Encryption (KE-BIBE) that enables parties to securely exchange cryptographic keys even an adversary is monitoring the communication channel between the parties. The proposed protocol combines biometrics with IBE in order to provide a secure way to access symmetric keys based on the identity of the users in unsecure environment. In the KE-BIOBE protocol, the message is first encrypted by the data owner using a traditional symmetric key before migrating it to a cloud storage. The symmetric key is then encrypted using public biometrics of the users selected by data owner to decrypt the message based on Fuzzy Identity-Based Encryption. Only the selected users will be able to decrypt the message by providing a fresh sample of their biometric data. The paper argues that the proposed solution eliminates the needs for a key distribution centre in traditional cryptography. It will also give data owner the power of finegrained sharing of encrypted data by control who can access their data.

κ -distributed protons in the solar wind and their charge-exchange coupling to energetic hydrogen

DOE PAGES

Heerikhuisen, J.; Zirnstein, Eric; Pogorelov, Nikolai

2015-03-16

The interaction between the solar wind and the interstellar medium represents a collision between two plasma flows, resulting in a heliosphere with an extended tail. While the solar wind is mostly ionized material from the corona, the interstellar medium is only partially ionized. The ion and neutral populations are coupled through charge-exchange collisions that operate on length scales of tens to hundreds of astronomical units. About half the interstellar hydrogen flows into the heliosphere where it may charge-exchange with solar wind protons. This process gives rise to a nonthermal proton, known as a pickup ion, which joins the plasma. Inmore » this paper we investigate the effects of approximating the total ion distribution of the subsonic solar wind as a generalized Lorentzian, or κ distribution, using an MHD neutral code. We illustrate the effect different values of the κ parameter have on both the structure of the heliosphere and the energetic neutral atom flux at 1 AU. We find that using a κ distribution in our simulations yields levels of energetic neutral atom flux that are within a factor of about 2 or 3 over the IBEX-Hi range of energies from 0.5 to 6 keV. In conclusion, while the presence of a suprathermal tail in the proton distribution leads to the production of high-energy neutrals, the sharp decline in the charge-exchange cross section around 10 keV mitigates the enhanced transfer of energy from the ions to the neutrals that might otherwise be expected.« less

DATA QUALITY OBJECTIVE SUMMARY REPORT FOR THE 105 K EAST ION EXCHANGE COLUMN MONOLITH

DOE Office of Scientific and Technical Information (OSTI.GOV)

JOCHEN, R.M.

2007-08-02

The 105-K East (KE) Basin Ion Exchange Column (IXC) cells, lead caves, and the surrounding vault are to be removed as necessary components in implementing ''Hanford Federal Facility Agreement and Consent Order'' (Ecology et al. 2003) milestone M-034-32 (Complete Removal of the K East Basin Structure). The IXCs consist of six units located in the KE Basin, three in operating positions in cells and three stored in a lead cave. Methods to remove the IXCs from the KE Basin were evaluated in KBC-28343, ''Disposal of K East Basin Ion Exchange Column Evaluation''. The method selected for removal was grouting themore » six IXCs into a single monolith for disposal at the Environmental Restoration Disposal Facility (ERDF). Grout will be added to the IXC cells, IXC lead caves containing spent IXCs, and in the spaces between the lead cave walls and metal skin, to immobilize the contaminants, provide self-shielding, minimize void space, and provide a structurally stable waste form. The waste to be offered for disposal is the encapsulated monolith defined by the exterior surfaces of the vault and the lower surface of the underlying slab. This document presents summary of the data quality objective (DQO) process establishing the decisions and data required to support decision-making activities for the disposition of the IXC monolith. The DQO process is completed in accordance with the seven-step planning process described in EPA QA/G-4, ''Guidance for the Data Quality Objectives Process'', which is used to clarify and study objectives; define the appropriate type, quantity, and quality of data; and support defensible decision-making. The DQO process involves the following steps: (1) state the problem; (2) identify the decision; (3) identify the inputs to the decision; (4) define the boundaries of the study; (5) develop a decision rule (DR); (6) specify tolerable limits on decision errors; and (7) optimize the design for obtaining data.« less

Three-dimensional ring current decay model

NASA Technical Reports Server (NTRS)

Fok, Mei-Ching; Moore, Thomas E.; Kozyra, Janet U.; Ho, George C.; Hamilton, Douglas C.

1995-01-01

This work is an extension of a previous ring current decay model. In the previous work, a two-dimensional kinetic model was constructed to study the temporal variations of the equatorially mirroring ring current ions, considering charge exchange and Coulomb drag losses along drift paths in a magnetic dipole field. In this work, particles with arbitrary pitch angle are considered. By bounce averaging the kinetic equation of the phase space density, information along magnetic field lines can be inferred from the equator. The three-dimensional model is used to simulate the recovery phase of a model great magnetic storm, similar to that which occurred in early February 1986. The initial distribution of ring current ions (at the minimum Dst) is extrapolated to all local times from AMPTE/CCE spacecraft observations on the dawnside and duskside of the inner magnetosphere spanning the L value range L = 2.25 to 6.75. Observations by AMPTE/CCE of ring current distributions over subsequent orbits during the storm recovery phase are compared to model outputs. In general, the calculated ion fluxes are consistent with observations, except for H(+) fluxes at tens of keV, which are always overestimated. A newly invented visualization idea, designated as a chromogram, is used to display the spatial and energy dependence of the ring current ion differential flux. Important features of storm time ring current, such as day-night asymmetry during injection and drift hole on the dayside at low energies (less than 10 keV), are manifested in the chromogram representation. The pitch angle distribution is well fit by the function, J(sub o)(1 + Ay(sup n)), where y is sine of the equatorial pitch angle. The evolution of the index n is a combined effect of charge exchange loss and particle drift. At low energies (less than 30 keV), both drift dispersion and charge exchange are important in determining n.

A three-dimensional ring current decay model

NASA Technical Reports Server (NTRS)

Fok, Mei-Ching; Moore, Thomas E.; Kozyra, Janet U.; Ho, George C.; Hamilton, Douglas C.

1994-01-01

This work is an extension of a previous ring current decay model. In the previous work, a two-dimensional kinetic model was constructed to study the temporal variations of the equatorially mirroring ring current ions, considering charge exchange and Coulomb drag losses along drift paths in a magnetic dipole field. In this work, particles with arbitrary pitch angle are considered. By bounce averaging the kinetic equation of the phase space density, information along magnetic field lines can be inferred from the equator. The three-dimensional model is used to simulate the recovery phase of a model great magnetic storm, similar to that which occurred in early February 1986. The initial distribution of ring current ions (at the minimum Dst) is extrapolated to all local times from AMPTE/CCE spacecraft observations on the dawn and dusk sides of the inner magnetosphere spanning the L value range L = 2.25 to 6.75. Observations by AMPTE/CCE of ring current distributions over subsequent orbits during the storm recovery phase are compared to model outputs. In general, the calculated ion fluxes are consistent with observations, except for H+ fluxes at tens of keV, which are always over-estimated. A newly-invented visualization idea, designated as a chromogram, is used to display the spatial and energy dependence of the ring current ion differential flux. Important features of storm-time ring current, such as day-night asymmetry during injection and drift hole on the dayside at low energies (less than 10 keV), are manifested in the chromogram representation. The pitch angle distribution is well fit by the function, j(sub o)(1+Ay(exp n)), where y is sine of the equatorial pitch angle. The evolution of the index n is a combined effect of charge exchange loss and particle drift. At low energies (less than 30 keV), both drift dispersion and charge exchange are important in determining n.

How can knowledge exchange portals assist in knowledge management for evidence-informed decision making in public health?

PubMed Central

2014-01-01

Background Knowledge exchange portals are emerging as web tools that can help facilitate knowledge management in public health. We conducted a review to better understand the nature of these portals and their contribution to knowledge management in public health, with the aim of informing future development of portals in this field. Methods A systematic literature search was conducted of the peer-reviewed and grey literature to identify articles that described the design, development or evaluation of Knowledge Exchange Portals KEPs in the public health field. The content of the articles was analysed, interpreted and synthesised in light of the objectives of the review. Results The systematic search yielded 2223 articles, of which fifteen were deemed eligible for review, including eight case studies, six evaluation studies and one commentary article. Knowledge exchange portals mainly included design features to support knowledge access and creation, but formative evaluation studies examining user needs suggested collaborative features supporting knowledge exchange would also be useful. Overall web usage statistics revealed increasing use of some of these portals over time; however difficulties remain in retaining users. There is some evidence to suggest that the use of a knowledge exchange portal in combination with tailored and targeted messaging can increase the use of evidence in policy and program decision making at the organisational level. Conclusions Knowledge exchange portals can be a platform for providing integrated access to relevant content and resources in one location, for sharing and distributing information and for bringing people together for knowledge exchange. However more performance evaluation studies are needed to determine how they can best support evidence-informed decision making in public health. PMID:24884530

How can knowledge exchange portals assist in knowledge management for evidence-informed decision making in public health?

PubMed

Quinn, Emma; Huckel-Schneider, Carmen; Campbell, Danielle; Seale, Holly; Milat, Andrew J

2014-05-12

Knowledge exchange portals are emerging as web tools that can help facilitate knowledge management in public health. We conducted a review to better understand the nature of these portals and their contribution to knowledge management in public health, with the aim of informing future development of portals in this field. A systematic literature search was conducted of the peer-reviewed and grey literature to identify articles that described the design, development or evaluation of Knowledge Exchange Portals KEPs in the public health field. The content of the articles was analysed, interpreted and synthesised in light of the objectives of the review. The systematic search yielded 2223 articles, of which fifteen were deemed eligible for review, including eight case studies, six evaluation studies and one commentary article. Knowledge exchange portals mainly included design features to support knowledge access and creation, but formative evaluation studies examining user needs suggested collaborative features supporting knowledge exchange would also be useful. Overall web usage statistics revealed increasing use of some of these portals over time; however difficulties remain in retaining users. There is some evidence to suggest that the use of a knowledge exchange portal in combination with tailored and targeted messaging can increase the use of evidence in policy and program decision making at the organisational level. Knowledge exchange portals can be a platform for providing integrated access to relevant content and resources in one location, for sharing and distributing information and for bringing people together for knowledge exchange. However more performance evaluation studies are needed to determine how they can best support evidence-informed decision making in public health.

Initial measurements of O-ion and He-ion decay rates observed from the Van Allen probes RBSPICE instrument

PubMed Central

Gerrard, Andrew; Lanzerotti, Louis; Gkioulidou, Matina; Mitchell, Donald; Manweiler, Jerry; Bortnik, Jacob; Keika, Kunihiro

2014-01-01

H-ion (∼45 keV to ∼600 keV), He-ion (∼65 keV to ∼520 keV), and O-ion (∼140 keV to ∼1130 keV) integral flux measurements, from the Radiation Belt Storm Probe Ion Composition Experiment (RBSPICE) instrument aboard the Van Allan Probes spacecraft B, are reported. These abundance data form a cohesive picture of ring current ions during the first 9 months of measurements. Furthermore, the data presented herein are used to show injection characteristics via the He-ion/H-ion abundance ratio and the O-ion/H-ion abundance ratio. Of unique interest to ring current dynamics are the spatial-temporal decay characteristics of the two injected populations. We observe that He-ions decay more quickly at lower L shells, on the order of ∼0.8 day at L shells of 3–4, and decay more slowly with higher L shell, on the order of ∼1.7 days at L shells of 5–6. Conversely, O-ions decay very rapidly (∼1.5 h) across all L shells. The He-ion decay time are consistent with previously measured and calculated lifetimes associated with charge exchange. The O-ion decay time is much faster than predicted and is attributed to the inclusion of higher-energy (> 500 keV) O-ions in our decay rate estimation. We note that these measurements demonstrate a compelling need for calculation of high-energy O-ion loss rates, which have not been adequately studied in the literature to date. Key Points We report initial observations of ring current ions We show that He-ion decay rates are consistent with theory We show that O-ions with energies greater than 500 keV decay very rapidly PMID:26167435

Collision cross sections of N2 by H+ impact at keV energies within time-dependent density-functional theory

NASA Astrophysics Data System (ADS)

Yu, W.; Gao, C.-Z.; Zhang, Y.; Zhang, F. S.; Hutton, R.; Zou, Y.; Wei, B.

2018-03-01

We calculate electron capture and ionization cross sections of N2 impacted by the H+ projectile at keV energies. To this end, we employ the time-dependent density-functional theory coupled nonadiabatically to molecular dynamics. To avoid the explicit treatment of the complex density matrix in the calculation of cross sections, we propose an approximate method based on the assumption of constant ionization rate over the period of the projectile passing the absorbing boundary. Our results agree reasonably well with experimental data and semi-empirical results within the measurement uncertainties in the considered energy range. The discrepancies are mainly attributed to the inadequate description of exchange-correlation functional and the crude approximation for constant ionization rate. Although the present approach does not predict the experiments quantitatively for collision energies below 10 keV, it is still helpful to calculate total cross sections of ion-molecule collisions within a certain energy range.

Calculations of stopping powers and inelastic mean free paths for 20 eV-20 keV electrons in 11 types of human tissue.

PubMed

Tan, Zhenyu; Liu, Wei

2013-12-01

Systematic calculations are performed for determining the stopping powers (SP) and inelastic mean free paths (IMFP) for 20 eV-20 keV electrons in 11 types of human tissue. The calculations are based on a dielectric model, including the Born-Ochkur exchange correction. The optical energy loss functions (OELF) are empirically evaluated, because of the lack of available experimental optical data for the 11 tissues under consideration. The evaluated OELFs are examined by the f-sum rule expected from the dielectric response theory, and by calculation of the mean excitation energy. The calculated SPs are compared with those for PMMA (polymethylmethacrylate, a tissue equivalent material) and liquid water. The SP and IMFP data presented here are the results for the 11 human tissues over the energy range of 20 eV-20 keV, and are of importance in radiotherapy planning and for studies of various radiation effects on human tissues. © 2013 Elsevier Ltd. All rights reserved.

THE STRUCTURE OF THE LOCAL HOT BUBBLE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, W.; Galeazzi, M.; Uprety, Y.

Diffuse X-rays from the Local Galaxy ( DXL ) is a sounding rocket mission designed to quantify and characterize the contribution of Solar Wind Charge eXchange (SWCX) to the Diffuse X-ray Background and study the properties of the Local Hot Bubble (LHB). Based on the results from the DXL mission, we quantified and removed the contribution of SWCX to the diffuse X-ray background measured by the ROSAT All Sky Survey. The “cleaned” maps were used to investigate the physical properties of the LHB. Assuming thermal ionization equilibrium, we measured a highly uniform temperature distributed around kT  = 0.097 keV ± 0.013 keV (FWHM) ± 0.006more » keV (systematic). We also generated a thermal emission measure map and used it to characterize the three-dimensional (3D) structure of the LHB, which we found to be in good agreement with the structure of the local cavity measured from dust and gas.« less

Charge Exchange Recombination Spectroscopy Based on Diagnostic Neutral Beam in HT-7 Tokamak

NASA Astrophysics Data System (ADS)

Shi, Yuejiang; Fu, Jia; Li, Yingying; William, Rowan; Huang, He; Wang, Fudi; Gao, Huixian; Huang, Juann; Zhou, Qian; Liu, Sheng; Zhang, Jian; Li, Jun; Xie, Yuanlai; Liu, Zhimin; Huang, Yiyun; Hu, Chundong; Wan, Baonian

2010-02-01

Charge exchange recombination spectroscopy (CXRS) based on a diagnostic neutral beam (DNB) installed in the HT-7 tokamak is introduced. DNB can provide a 6 A extracted current at 50 kV for 0.1 s in hydrogen. It can penetrate into the core plasma in HT-7. The CXRS system is designed to observe charge exchange (CX) transitions in the visible spectrum. CX light from the beam is focused onto 10 optical fibers, which view the plasma from -5 cm to 20 cm. The CXRS system can measure the ion temperature as low as 0.1 keV. With CXRS, the local ion temperature profile in HT-7 was obtained for the first time.

Upper-limit charge exchange cross sections for mercury (plus) on molybdenum and cesium (plus) on aluminum

NASA Technical Reports Server (NTRS)

Dugan, J. V., Jr.

1972-01-01

Upper-limit charge exchange cross sections are calculated for Hg(+) on Mo and Cs(+) on Al. The cross sections are calculated from the polarization interaction at low ion energies (1 to 500 eV) and by assuming favorable curve crossings with a hard-core reaction radius at higher energies (500 eV to 10 keV). The cross sections for Hg(+) on Mo becomes greater than corresponding Hg Hg(+) resonance values at ion energies below 2 eV, whereas the Cs(+) Al values remain considerably lower than the Cs(+)Cs resonance value at all ion energies. It is also shown that charge exchange of slow Hg(+) with Mo may be important for spacecraft with electron bombardment thrusters.

A Collaborative Approach to Defining the Usefulness of Impact: Lessons from a Knowledge Exchange Project Involving Academics and Social Work Practitioners

ERIC Educational Resources Information Center

Wilkinson, Heather; Gallagher, Michael; Smith, Mark

2012-01-01

This paper reports on a knowledge exchange project involving academics and practitioners in six local authority social work departments. It contributes to recent debates about the coproduction of knowledge, presenting findings in three key areas: the importance of relationships for knowledge exchange; "what works" for practitioners…

What can be Learned from X-Ray Spectroscopy Concerning Hot Gas in the Local Bubble and Charge Exchange Processes

NASA Technical Reports Server (NTRS)

Snowden, Steven L.

2007-01-01

Solar wind charge exchange produces diffuse X-ray emission with a variable surface brightness comparable to that of the cosmic background. While the temporal variation of the charge exchange emission allows some separation of the components, there remains a great deal of uncertainty as to the zero level of both. Because the production mechanisms of the two components are considerably different, their spectra would provide critical diagnostics to the understanding of both. However, current X-ray observatories are very limited in both spectral resolution and sensitivity in the critical soft X-ray (less than 1.0 keV) energy range. Non-dispersive high-resolution spectrometers, such as the calorimeter proposed for the Spectrum Roentgen Gamma mission, will be extremely useful in distinguishing the cascade emission of charge exchange from the spectra of thermal bremsstrahlung cosmic plasmas.

Effects of electronic excitation in 150 keV Ni ion irradiation of metallic systems

NASA Astrophysics Data System (ADS)

Zarkadoula, Eva; Samolyuk, German; Weber, William J.

2018-01-01

We use the two-temperature model in molecular dynamic simulations of 150 keV Ni ion cascades in nickel and nickel-based alloys to investigate the effect of the energy exchange between the atomic and the electronic systems during the primary stages of radiation damage. We find that the electron-phonon interactions result in a smaller amount of defects and affect the cluster formation, resulting in smaller clusters. These results indicate that ignoring the local heating due to the electrons results in the overestimation of the amount of damage and the size of the defect clusters. A comparison of the average defect production to the Norgett-Robinson-Torrens (NRT) prediction over a range of energies is provided.

Monte Carlo simulation of neutral-beam injection for mirror fusion reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Ronald Lee

1979-01-01

Computer simulation techniques using the Monte Carlo method have been developed for application to the modeling of neutral-beam intection into mirror-confined plasmas of interest to controlled thermonuclear research. The energetic (10 to 300 keV) neutral-beam particles interact with the target plasma (T i ~ 10 to 100 keV) through electron-atom and ion-atom collisional ionization as well as ion-atom charge-transfer (charge-exchange) collisions to give a fractional trapping of the neutral beam and a loss of charge-transfer-produced neutrals which escape to bombard the reactor first wall. Appropriate interaction cross sections for these processes are calculated for the assumed anisotropic, non-Maxwellian plasma ionmore » phase-space distributions.« less

Five principles for the practice of knowledge exchange in environmental management.

PubMed

Reed, M S; Stringer, L C; Fazey, I; Evely, A C; Kruijsen, J H J

2014-12-15

This paper outlines five principles for effective practice of knowledge exchange, which when applied, have the potential to significantly enhance the impact of environmental management research, policy and practice. The paper is based on an empirical analysis of interviews with 32 researchers and stakeholders across 13 environmental management research projects, each of which included elements of knowledge co-creation and sharing in their design. The projects focused on a range of upland and catchment management issues across the UK, and included Research Council, Government and NGO funded projects. Preliminary findings were discussed with knowledge exchange professionals and academic experts to ensure the emerging principles were as broadly applicable as possible across multiple disciplines. The principles suggest that: knowledge exchange needs to be designed into research; the needs of likely research users and other stakeholders should be systematically represented in the research where possible; and long-term relationships must be built on trust and two-way dialogue between researchers and stakeholders in order to ensure effective co-generation of new knowledge. We found that the delivery of tangible benefits early on in the research process helps to ensure continued motivation and engagement of likely research users. Knowledge exchange is a flexible process that must be monitored, reflected on and continuously refined, and where possible, steps should be taken to ensure a legacy of ongoing knowledge exchange beyond initial research funding. The principles have been used to inform the design of knowledge exchange and stakeholder engagement guidelines for two international research programmes. They are able to assist researchers, decision-makers and other stakeholders working in contrasting environmental management settings to work together to co-produce new knowledge, and more effectively share and apply existing knowledge to manage environmental change. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Positrons in the Galaxy: Their Births, Marriages and Deaths

NASA Technical Reports Server (NTRS)

Skinner, Gerald K.

2010-01-01

High energy (approximately GeV) positrons are seen within cosmic rays and observation of a narrow line at 511 keV shows that positrons are annihilating in the galaxy after slowing down to approximately keV energies or less. Our state of knowledge of the origin of these positrons, of the formation of positronium 'atoms', and of the circumstances of their annihilation or escape from the galaxy are reviewed and the question of whether the two phenomena are linked is discussed.

Kinetics of chromatid break repair in G2-human fibroblasts exposed to low- and high-LET radiations

NASA Technical Reports Server (NTRS)

Kawata, T.; Durante, M.; George, K.; Furusawa, Y.; Gotoh, E.; Takai, N.; Wu, H.; Cucinotta, F. A.

2001-01-01

The purpose of this study is to determine the kinetics of chromatid break rejoining following exposure to radiations of different quality. Exponentially growing human fibroblast cells AG1522 were irradiated with gamma-rays, energetic carbon (290 MeV/u), silicon (490 MeV/u) and iron (200 MeV/u, 600 MeV/u). Chromosomes were prematurely condensed using calyculin A. Prematurely condensed chromosomes were collected after several post-irradiation incubation times, ranging from 5 to 600 minutes, and the number of chromatid breaks and exchanges in G2 cells were scored. The relative biological effectiveness (RBE) for initial chromatid breaks per unit dose showed LET dependency having a peak at 55 keV/micrometers silicon (2.4) or 80 keV/micrometers carbon particles (2.4) and then decreased with increasing LET. The kinetics of chromatid break rejoining following low- or high-LET irradiation consisted of two exponential components. Chromatid breaks decreased rapidly after exposure, and then continued to decrease at a slower rate. The rejoining kinetics was similar for exposure to each type of radiation, although the rate of unrejoined breaks was higher for high-LET radiation. Chromatid exchanges were also formed quickly.

Web-Based Knowledge Exchange through Social Links in the Workplace

ERIC Educational Resources Information Center

Filipowski, Tomasz; Kazienko, Przemyslaw; Brodka, Piotr; Kajdanowicz, Tomasz

2012-01-01

Knowledge exchange between employees is an essential feature of recent commercial organisations on the competitive market. Based on the data gathered by various information technology (IT) systems, social links can be extracted and exploited in knowledge exchange systems of a new kind. Users of such a system ask their queries and the system…

DXL: A Sounding Rocket Mission for the Study of Solar Wind Charge Exchange and Local Hot Bubble X-Ray Emission

NASA Technical Reports Server (NTRS)

Galeazzi, M.; Prasai, K.; Uprety, Y.; Chiao, M.; Collier, M. R.; Koutroumpa, D.; Porter, F. S.; Snowden, S.; Cravens, T.; Robertson, I.;

Time-dependent spin-density-functional-theory description of He+-He collisions

NASA Astrophysics Data System (ADS)

Baxter, Matthew; Kirchner, Tom; Engel, Eberhard

2017-09-01

Theoretical total cross-section results for all ionization and capture processes in the He+-He collision system are presented in the approximate impact energy range of 10-1000 keV/amu. Calculations were performed within the framework of time-dependent spin-density functional theory. The Krieger-Li-Iafrate approximation was used to determine an accurate exchange-correlation potential in the exchange-only limit. The results of two models, one where electron translation factors in the orbitals used to calculate the potential are ignored and another where partial electron translation factors are included, are compared with available experimental data as well as a selection of previous theoretical calculations.

Identifying Effective Drivers for Knowledge Exchange in the United Kingdom

ERIC Educational Resources Information Center

Upton, Stevie

2012-01-01

This paper examines the drivers for knowledge exchange in British research-intensive universities, at a time when research impact is coming to be seen as an increasingly important outcome of research in all disciplines. It provides evidence of an over-emphasis of the economic benefits of knowledge exchange in the policy sphere and of a quite…

Theory, Practice and Policy: A Longitudinal Study of University Knowledge Exchange in the UK

ERIC Educational Resources Information Center

Zhang, Qiantao

2018-01-01

This article examines the progress of university knowledge exchange in the United Kingdom over a decade, linking theory, practice and policy. As indicated by the literature, the performance of university knowledge exchange is influenced by institutional and locational characteristics. Data on 133 UK universities between 2003-2004 and 2012-2013 are…

Inelastic frontier: Discovering dark matter at high recoil energy

DOE PAGES

Bramante, Joseph; Fox, Patrick J.; Kribs, Graham D.; ...

2016-12-27

There exist well-motivated models of particle dark matter which predominantly scatter inelastically off nuclei in direct detection experiments. This inelastic transition causes the dark matter to upscatter in terrestrial experiments into an excited state up to 550 keV heavier than the dark matter itself. An inelastic transition of this size is highly suppressed by both kinematics and nuclear form factors. In this paper, we extend previous studies of inelastic dark matter to determine the present bounds on the scattering cross section and the prospects for improvements in sensitivity. Three scenarios provide illustrative examples: nearly pure Higgsino supersymmetric dark matter, magnetic inelasticmore » dark matter, and inelastic models with dark photon exchange. We determine the elastic scattering rate (through loop diagrams involving the heavy state) as well as verify that exothermic transitions are negligible (in the parameter space we consider). Presently, the strongest bounds on the cross section are from xenon at LUX-PandaX (when the mass splitting δ≲160 keV), iodine at PICO (when 160≲δ≲300 keV), and tungsten at CRESST (when δ≳300 keV). Amusingly, once δ≳200 keV, weak scale (and larger) dark matter–nucleon scattering cross sections are allowed. The relative competitiveness of these diverse experiments is governed by the upper bound on the recoil energies employed by each experiment, as well as strong sensitivity to the mass of the heaviest element in the detector. Several implications, including sizable recoil energy-dependent annual modulation and improvements for future experiments, are discussed. We show that the xenon experiments can improve on the PICO results, if they were to analyze their existing data over a larger range of recoil energies, i.e., 20–500 keV Intriguingly, CRESST has reported several events in the recoil energy range 45–100 keV that, if interpreted as dark matter scattering, is compatible with δ~200 keV and an approximately weak scale cross section. Here, future data from PICO and CRESST can test this speculation, while xenon experiments could verify or refute this upon analyzing their higher energy recoil data.« less

Applying knowledge engineering and representation methods to improve support vector machine and multivariate probabilistic neural network CAD performance

NASA Astrophysics Data System (ADS)

Land, Walker H., Jr.; Anderson, Frances; Smith, Tom; Fahlbusch, Stephen; Choma, Robert; Wong, Lut

2005-04-01

Achieving consistent and correct database cases is crucial to the correct evaluation of any computer-assisted diagnostic (CAD) paradigm. This paper describes the application of artificial intelligence (AI), knowledge engineering (KE) and knowledge representation (KR) to a data set of ~2500 cases from six separate hospitals, with the objective of removing/reducing inconsistent outlier data. Several support vector machine (SVM) kernels were used to measure diagnostic performance of the original and a "cleaned" data set. Specifically, KE and ER principles were applied to the two data sets which were re-examined with respect to the environment and agents. One data set was found to contain 25 non-characterizable sets. The other data set contained 180 non-characterizable sets. CAD system performance was measured with both the original and "cleaned" data sets using two SVM kernels as well as a multivariate probabilistic neural network (PNN). Results demonstrated: (i) a 10% average improvement in overall Az and (ii) approximately a 50% average improvement in partial Az.

DYNACLIPS (DYNAmic CLIPS): A dynamic knowledge exchange tool for intelligent agents

NASA Technical Reports Server (NTRS)

Cengeloglu, Yilmaz; Khajenoori, Soheil; Linton, Darrell

1994-01-01

In a dynamic environment, intelligent agents must be responsive to unanticipated conditions. When such conditions occur, an intelligent agent may have to stop a previously planned and scheduled course of actions and replan, reschedule, start new activities and initiate a new problem solving process to successfully respond to the new conditions. Problems occur when an intelligent agent does not have enough knowledge to properly respond to the new situation. DYNACLIPS is an implementation of a framework for dynamic knowledge exchange among intelligent agents. Each intelligent agent is a CLIPS shell and runs a separate process under SunOS operating system. Intelligent agents can exchange facts, rules, and CLIPS commands at run time. Knowledge exchange among intelligent agents at run times does not effect execution of either sender and receiver intelligent agent. Intelligent agents can keep the knowledge temporarily or permanently. In other words, knowledge exchange among intelligent agents would allow for a form of learning to be accomplished.

Did you have an impact? A theory-based method for planning and evaluating knowledge-transfer and exchange activities in occupational health and safety.

PubMed

Kramer, Desré M; Wells, Richard P; Carlan, Nicolette; Aversa, Theresa; Bigelow, Philip P; Dixon, Shane M; McMillan, Keith

2013-01-01

Few evaluation tools are available to assess knowledge-transfer and exchange interventions. The objective of this paper is to develop and demonstrate a theory-based knowledge-transfer and exchange method of evaluation (KEME) that synthesizes 3 theoretical frameworks: the promoting action on research implementation of health services (PARiHS) model, the transtheoretical model of change, and a model of knowledge use. It proposes a new term, keme, to mean a unit of evidence-based transferable knowledge. The usefulness of the evaluation method is demonstrated with 4 occupational health and safety knowledge transfer and exchange (KTE) implementation case studies that are based upon the analysis of over 50 pre-existing interviews. The usefulness of the evaluation model has enabled us to better understand stakeholder feedback, frame our interpretation, and perform a more comprehensive evaluation of the knowledge use outcomes of our KTE efforts.

Effects of electronic excitation in 150 keV Ni ion irradiation of metallic systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zarkadoula, Eva; Samolyuk, German; Weber, William J.

We use the two-temperature model in molecular dynamic simulations of 150 keV Ni ion cascades in nickel and nickel-based alloys to investigate the effect of the energy exchange between the atomic and the electronic systems during the primary stages of radiation damage. We find that the electron-phonon interactions result in a smaller amount of defects and affect the cluster formation, resulting in smaller clusters. These results indicate that ignoring the local heating due to the electrons results in the overestimation of the amount of damage and the size of the defect clusters. A comparison of the average defect production tomore » the Norgett-Robinson-Torrens (NRT) prediction over a range of energies is provided.« less

Effects of electronic excitation in 150 keV Ni ion irradiation of metallic systems

DOE PAGES

Zarkadoula, Eva; Samolyuk, German; Weber, William J.

2018-01-18

We use the two-temperature model in molecular dynamic simulations of 150 keV Ni ion cascades in nickel and nickel-based alloys to investigate the effect of the energy exchange between the atomic and the electronic systems during the primary stages of radiation damage. We find that the electron-phonon interactions result in a smaller amount of defects and affect the cluster formation, resulting in smaller clusters. These results indicate that ignoring the local heating due to the electrons results in the overestimation of the amount of damage and the size of the defect clusters. A comparison of the average defect production tomore » the Norgett-Robinson-Torrens (NRT) prediction over a range of energies is provided.« less

SeaQuaKE: Sea-optimized Quantum Key Exchange

DTIC Science & Technology

2014-06-01

is led by Applied Communications Sciences under the ONR Free Space Optical Quantum Key Distribution Special Notice (13-SN-0004 under ONRBAA13-001...In addition, we discuss our initial progress towards the free - space quantum channel model and planning for the experimental validation effort. 15...SUBJECT TERMS Quantum communications, free - space optical communications 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT Same as

SeaQuaKE: Sea-optimized Quantum Key Exchange

DTIC Science & Technology

2015-01-01

of photon pairs in both polarization [3] and time-bin [4] degrees of freedom simultaneously. Entanglement analysis components in both the...greater throughput per entangled photon pair compared to alternative sources that encode in only a Photon -pair source Time-bin entanglement ...Polarization Entanglement & Pair Generation Hyperentangled Photon Pair Source •Wavelength availability • Power • Pulse rate Time-bin Mux • Waveguide vs

Knowledge exchange in the UK CLAHRCs.

PubMed

Racko, Girts

2018-04-09

Purpose The purpose of this paper is to examine how knowledge exchange between academics and clinicians in Collaborations for Leadership in Applied Health Research and Care (CLAHRCs) is influenced by their social position based on their symbolic and social capitals, that is, their personal professional status and connections to high-status professional peers, knowledge brokers, and unfamiliar professional peers. Design/methodology/approach Using an online survey, the author triangulates the cross-sectional measurement of the effects of academic and clinicians' social position in the initial and later phases of CLAHRCs with the longitudinal measurement of these effects over a two-year period. Findings First, academics and clinicians with a higher personal professional status are more likely to develop joint networks and decision making both in the early and later phases of a CLAHRC. Second, academics and clinicians who are more connected to higher status occupational peers are more likely to develop joint networks in the early phase of a knowledge exchange partnership but are less likely to become engaged in joint networks over time. Third, involvement of knowledge brokers in the networks of academics and clinicians is likely to facilitate their inter-professional networking only in the later partnership phase. Practical implications Academics and clinicians' capitals have a distinctive influence on knowledge exchange in the early and later phases of CLAHRCs and on a change in knowledge exchange over a two-year period. Originality/value Prior research on CLAHRCs has examined how knowledge exchange between academics and clinicians can be encouraged by the creation of shared governance mechanisms. The author advances this research by highlighting the role of their social position in facilitating knowledge exchange.

Factors influencing rural and urban emergency clinicians' participation in an online knowledge exchange intervention.

PubMed

Curran, Janet A; Murphy, Andrea L; Sinclair, Douglas; McGrath, Patrick

2013-01-01

Rural emergency departments (EDs) generally have limited access to continuing education and are typically staffed by clinicians without pediatric emergency specialty training. Emergency care of children is complex and the majority of children receive emergency care in non-pediatric tertiary care centers. In recent decades, there has been a call to action to improve quality and safety in the emergency care of children. Of the one million ED visits by children in Ontario in 2005-2006, one in three visited more than once in a year and one in 15 returned to the ED within 72 hours of the index visit. This study explored factors influencing rural and urban ED clinicians' participation in a Web-based knowledge exchange intervention that focused on best practice knowledge about pediatric emergency care. The following questions guided the study: (i) What are the individual, context of practice or knowledge factors which impact a clinician's decision to participate in a Web-based knowledge exchange intervention?; (ii) What are clinicians' perceptions of organizational expectations regarding knowledge and information sources to be used in practice?; and (iii) What are the preferred knowledge sources of rural and urban emergency clinicians? A Web-based knowledge exchange intervention, the Pediatric Emergency Care Web Based Knowledge Exchange Project, for rural and urban ED clinicians was developed. The website contained 12 pediatric emergency practice learning modules with linked asynchronous discussion forums. The topics for the modules were determined through a needs assessment and the module content was developed by known experts in the field. A follow-up survey was sent to a convenience sample of 187 clinicians from nine rural and two urban Canadian EDs participating in the pediatric emergency Web-based knowledge exchange intervention study. The survey response rate was 56% (105/187). Participation in the knowledge exchange intervention was related to individual involvement in research activities (χ(2)=5.23, p=0.019), consultation with colleagues from other EDs (χ(2)=6.37, p=0.01) and perception of organizational expectations to use research evidence to guide practice (χ(2)=5.52, p=0.015). Most clinicians (95/105 or 92%) reported relying on colleagues from their own ED as a primary knowledge source. Urban clinicians were more likely than their rural counterparts to perceive that use of research evidence to guide practice was an expectation. Rural clinicians were more likely to rely on physicians from their own ED as a preferred knowledge source. The decision made by emergency clinicians to participate in a Web-based knowledge exchange intervention was influenced by a number of individual and contextual factors. Differences in these factors and preferences for knowledge sources require further characterization to enhance engagement of rural ED clinicians in online knowledge exchange interventions.

Performance of the EBIT calorimeter spectrometer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Porter, Frederick Scott; Gygax, John; Kelley, Richard L.

The EBIT calorimeter spectrometer (ECS) is a new high-resolution, broadband x-ray spectrometer that has recently been installed at the Electron Beam Ion Trap Facility (EBIT) at the Lawrence Livermore National Laboratory. The ECS is an entirely new production class spectrometer that replaces the XRS/EBIT spectrometer that has been operating at EBIT since 2000. The ECS utilizes a 32-pixel x-ray calorimeter array from the XRS instrument on the Suzaku x-ray observatory. Eighteen of the pixels are optimized for the 0.1-10 keV band and yield 4.5 eV full width at half maximum energy resolution and 95% quantum efficiency at 6 keV. Inmore » addition, the ECS includes 14 detector pixels that are optimized for the high-energy band with a bandpass from 0.5 to over 100 keV with 34 eV resolution and 32% quantum efficiency at 60 keV. The ECS detector array is operated at 50 mK using a five stage cryogenic system that is entirely automated. The instrument takes data continuously for over 65 h with a 2.5 h recycle time. The ECS is a nondispersive, broadband, highly efficient spectrometer that is one of the prime instruments at the EBIT facility. The instrument is used for studies of absolute cross sections, charge exchange recombination, and x-ray emission from nonequilibrium plasmas, among other measurements in our laboratory astrophysics program.« less

Regional turbulence patterns driven by meso- and submesoscale processes in the Caribbean Sea

NASA Astrophysics Data System (ADS)

C. Pérez, Juan G.; R. Calil, Paulo H.

2017-09-01

The surface ocean circulation in the Caribbean Sea is characterized by the interaction between anticyclonic eddies and the Caribbean Upwelling System (CUS). These interactions lead to instabilities that modulate the transfer of kinetic energy up- or down-cascade. The interaction of North Brazil Current rings with the islands leads to the formation of submesoscale vorticity filaments leeward of the Lesser Antilles, thus transferring kinetic energy from large to small scales. Within the Caribbean, the upper ocean dynamic ranges from large-scale currents to coastal upwelling filaments and allow the vertical exchange of physical properties and supply KE to larger scales. In this study, we use a regional model with different spatial resolutions (6, 3, and 1 km), focusing on the Guajira Peninsula and the Lesser Antilles in the Caribbean Sea, in order to evaluate the impact of submesoscale processes on the regional KE energy cascade. Ageostrophic velocities emerge as the Rossby number becomes O(1). As model resolution is increased submesoscale motions are more energetic, as seen by the flatter KE spectra when compared to the lower resolution run. KE injection at the large scales is greater in the Guajira region than in the others regions, being more effectively transferred to smaller scales, thus showing that submesoscale dynamics is key in modulating eddy kinetic energy and the energy cascade within the Caribbean Sea.

Knowledge brokering on emissions modelling in Strategic Environmental Assessment of Estonian energy policy with special reference to the LEAP model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuldna, Piret, E-mail: piret.kuldna@seit.ee; Peterson, Kaja; Kuhi-Thalfeldt, Reeli

Strategic Environmental Assessment (SEA) serves as a platform for bringing together researchers, policy developers and other stakeholders to evaluate and communicate significant environmental and socio-economic effects of policies, plans and programmes. Quantitative computer models can facilitate knowledge exchange between various parties that strive to use scientific findings to guide policy-making decisions. The process of facilitating knowledge generation and exchange, i.e. knowledge brokerage, has been increasingly explored, but there is not much evidence in the literature on how knowledge brokerage activities are used in full cycles of SEAs which employ quantitative models. We report on the SEA process of the nationalmore » energy plan with reflections on where and how the Long-range Energy Alternatives Planning (LEAP) model was used for knowledge brokerage on emissions modelling between researchers and policy developers. Our main suggestion is that applying a quantitative model not only in ex ante, but also ex post scenario modelling and associated impact assessment can facilitate systematic and inspiring knowledge exchange process on a policy problem and capacity building of participating actors. - Highlights: • We examine the knowledge brokering on emissions modelling between researchers and policy developers in a full cycle of SEA. • Knowledge exchange process can evolve at any modelling stage within SEA. • Ex post scenario modelling enables systematic knowledge exchange and learning on a policy problem.« less

Remote Sensing of Icy Galilean Moon Surface and Atmospheric Composition Using Low Energy (1 eV-4 keV) Neutral Atom Imaging

NASA Technical Reports Server (NTRS)

Collier, M. R.; Sittler, E.; Chornay, D.; Cooper, J. F.; Coplan, M.; Johnson, R. E.

2004-01-01

We describe a low energy neutral atom imager suitable for composition measurements Europa and other icy Galilean moons in the Jovian magnetosphere. This instrument employs conversion surface technology and is sensitive to either neutrals converted to negative ions, neutrals converted to positive ions and the positive ions themselves depending on the power supply. On a mission such as the Jupiter Icy Moons Orbiter (JIMO), two back-to-back sensors would be flown with separate power supplies fitted to the neutral atom and iodneutral atom sides. This will allow both remote imaging of 1 eV < E < 4 keV neutrals from icy moon surfaces and atmospheres, and in situ measurements of ions at similar energies in the moon ionospheres and Jovian magnetospheric plasma. The instrument provides composition measurements of the neutrals and ions that enter the spectrometer with a mass resolution dependent on the time-of-flight subsystem and capable of resolving molecules. The lower energy neutrals, up to tens of eV, arise from atoms and molecules sputtered off the moon surfaces and out of the moon atmospheres by impacts of more energetic (keV to MeV) ions from the magnetosphere. Direct Simulation Monte Carlo (DSMC) models are used to convert measured neutral abundances to compositional distributions of primary and trace species in the sputtered surfaces and atmospheres. The escaping neutrals can also be detected as ions after photo- or plasma-ionization and pickup. Higher energy, keV neutrals come from charge exchange of magnetospheric ions in the moon atmospheres and provide information on atmospheric structure. At the jovicentric orbits of the icy moons the presence of toroidal gas clouds, as detected at Europa's orbit, provide M e r opportunities to analyze both the composition of neutrals and ions originating from the moon surfaces, and the characteristics of magnetospheric ions interacting with neutral cloud material. Charge exchange of low energy ions near the moons, and directional distributions of the resultant neutrals, allow indirect global mapping of magnetic field structures around the moons. Temporal variation of the magnetic structures can be linked to induced magnetic fields associated with subsurface oceans.

The Life Science Exchange: a case study of a sectoral and sub-sectoral knowledge exchange programme.

PubMed

Perkins, Brian Lee; Garlick, Rob; Wren, Jodie; Smart, Jon; Kennedy, Julie; Stephens, Phil; Tudor, Gwyn; Bisson, Jonathan; Ford, David V

2016-04-27

Local and national governments have implemented sector-specific policies to support economic development through innovation, entrepreneurship and knowledge exchange. Supported by the Welsh Government through the European Regional Development Fund, The Life Science Exchange® project was created with the aim to increase interaction between stakeholders, to develop more effective knowledge exchange mechanisms, and to stimulate the formation and maintenance of long-term collaborative relationships within the Welsh life sciences ecosystem. The Life Science Exchange allowed participants to interact with other stakeholder communities (clinical, academic, business, governmental), exchange perspectives and discover new opportunities. Six sub-sector focus groups comprising over 200 senior stakeholders from academia, industry, the Welsh Government and National Health Service were established. Over 18 months, each focus group provided input to inform healthcare innovation policy and knowledge mapping exercises of their respective sub-sectors. Collaborative projects identified during the focus groups and stakeholder engagement were further developed through sandpit events and bespoke support. Each sub-sector focus group produced a report outlining the significant strengths and opportunities in their respective areas of focus, made recommendations to overcome any 'system failures', and identified the stakeholder groups which needed to take action. A second outcome was a stakeholder-driven knowledge mapping exercise for each area of focus. Finally, the sandpit events and bespoke support resulted in participants generating more than £1.66 million in grant funding and inward investment. This article outlines four separate outcomes from the Life Science Exchange programme. The Life Science Exchange process has resulted in a multitude of collaborations, projects, inward investment opportunities and special interest group formations, in addition to securing over ten times its own costs in funding for Wales. The Life Science Exchange model is a simple and straightforward mechanism for a regional or national government to adapt and implement in order to improve innovation, skills, networks and knowledge exchange.

Key characteristics of knowledge transfer and exchange in healthcare: integrative literature review.

PubMed

Pentland, Duncan; Forsyth, Kirsty; Maciver, Donald; Walsh, Mike; Murray, Richard; Irvine, Linda; Sikora, Simon

2011-07-01

This paper presents the results of a review of literature relating to knowledge transfer and exchange in healthcare. Treatment, planning and policy decisions in contemporary nursing and healthcare should be based on sound evidence wherever possible, but research knowledge remains generally underused. Knowledge transfer and exchange initiatives aim to facilitate the accessibility, application and production of evidence and may provide solutions to this challenge. This review was conducted to help inform the design and implementation of knowledge transfer and exchange activities for a large healthcare organization. Databases: ASSIA, Business Source Premier, CINAHL, PsychInfo, Medline and the Cochrane Database of Systematic Reviews. An integrative literature review was carried out including an extensive literature search. English language systematic reviews, literature reviews, primary quantitative and qualitative papers and grey literature of high relevance evaluating, describing or discussing knowledge transfer or exchange activities in healthcare were included for review (January 1990-September 2009). Thirty-three papers were reviewed (four systematic reviews, nine literature reviews, one environmental scan, nine empirical studies and ten case studies). Robust research into knowledge transfer and exchange in healthcare is limited. Analysis of a wide range of evidence indicates a number of commonly featured characteristics but further evaluation of these activities would benefit their application in facilitating evidence-based practice in nursing. © 2011 The Authors. Journal of Advanced Nursing © 2011 Blackwell Publishing Ltd.

A model of air-sea gas exchange incorporating the physics of the turbulent boundary layer and the properties of the sea surface

NASA Astrophysics Data System (ADS)

Soloviev, Alexander; Schluessel, Peter

The model presented contains interfacial, bubble-mediated, ocean mixed layer, and remote sensing components. The interfacial (direct) gas transfer dominates under conditions of low and—for quite soluble gases like CO2—moderate wind speeds. Due to the similarity between the gas and heat transfer, the temperature difference, ΔT, across the thermal molecular boundary layer (cool skin of the ocean) and the interfacial gas transfer coefficient, Kint are presumably interrelated. A coupled parameterization for ΔT and Kint has been derived in the context of a surface renewal model [Soloviev and Schluessel, 1994]. In addition to the Schmidt, Sc, and Prandtl, Pr, numbers, the important parameters are the surface Richardson number, Rƒ0, and the Keulegan number, Ke. The more readily available cool skin data are used to determine the coefficients that enter into both parameterizations. At high wind speeds, the Ke-number dependence is further verified with the formula for transformation of the surface wind stress to form drag and white capping, which follows from the renewal model. A further extension of the renewal model includes effects of solar radiation and rainfall. The bubble-mediated component incorporates the Merlivat et al. [1993] parameterization with the empirical coefficients estimated by Asher and Wanninkhof [1998]. The oceanic mixed layer component accounts for stratification effects on the air-sea gas exchange. Based on the example of GasEx-98, we demonstrate how the results of parameterization and modeling of the air-sea gas exchange can be extended to the global scale, using remote sensing techniques.

Exchanging clinical knowledge via Internet.

PubMed

Buchan, I E; Hanka, R

1997-11-01

The need for effective and efficient exchange of clinical knowledge is increasing. Paper based methods for managing clinical knowledge are not meeting the demand for knowledge and this has undoubtedly contributed to the widely reported failures of clinical guidelines. Internet affords both opportunities and dangers for clinical knowledge. Systems such as Wax have demonstrated the importance of intuitive structure in the management of knowledge. We report on a new initiative for the global management of clinical knowledge.

SeaQuaKE: Sea-optimized Quantum Key Exchange

DTIC Science & Technology

2014-11-01

ONRBAA13-001). In this technical report, we describe modeling results of an entangled photon - pair source based on spontaneous four-wave mixing for...Distribution Special Notice (13-SN- 0004 under ONRBAA13-001). In this technical report, we describe modeling results of an entangled photon - pair ...areas over the last quarter include (i) development of a wavelength-dependent, entangled photon - pair source model and (ii) end-to-end system modeling

Biological Effectiveness of Accelerated Particles for the Induction of Chromosome Damage Measured in Metaphase and Interphase Human Lymphocytes

NASA Technical Reports Server (NTRS)

George, Kerry; Durante, Marco; Willingham, Veronica; Wu, Honglu; Yang, Tracy C.; Cucinotta, Francis A.

2003-01-01

Chromosome aberrations were investigated in human lymphocytes after in vitro exposure to 1H-, 3He-, 12C-, 40Ar-, 28Si-, 56Fe-, or 197Au-ion beams, with LET ranging from approximately 0.4-1393 keV/microm in the dose range of 0.075-3 Gy. Dose-response curves for chromosome exchanges, measured at the first mitosis postirradiation using fluorescence in situ hybridization (FISH) with whole-chromosome probes, were fitted with linear or linear-quadratic functions. The relative biological effectiveness (RBE) was estimated from the initial slope of the dose-response curve for chromosomal damage with respect to low- or high-dose-rate gamma rays. Estimates of RBEmax values for mitotic spreads, which ranged from near 0.7 to 11.1 for total exchanges, increased with LET, reaching a maximum at about 150 keV/microm, and decreased with further increase in LET. RBEs for complex aberrations are undefined due to the lack of an initial slope for gamma rays. Additionally, the effect of mitotic delay on RBE values was investigated by measuring chromosome aberrations in interphase after chemically induced premature chromosome condensation (PCC), and values were up to threefold higher than for metaphase analysis.

Energetic Nitrogen Ions within the Inner Magnetosphere of Saturn

NASA Astrophysics Data System (ADS)

Sittler, E. C.; Johnson, R. E.; Richardson, J. D.; Jurac, S.; Moore, M.; Cooper, J. F.; Mauk, B. H.; Smith, H. T.; Michael, M.; Paranicus, C.; Armstrong, T. P.; Tsurutani, B.; Connerney, J. E. P.

2003-05-01

Titan's interaction with Saturn's magnetosphere will result in the energetic ejection of atomic nitrogen atoms into Saturn's magnetosphere due to dissociation of N2 by electrons, ions, and UV photons. The ejection of N atoms into Saturn's magnetosphere will form a nitrogen torus around Saturn with mean density of about 4 atoms/cm3 with source strength of 4.5x1025 atoms/sec. These nitrogen atoms are ionized by photoionization, electron impact ionization and charge exchange reactions producing an N+ torus of 1-4 keV suprathermal ions centered on Titan's orbital position. We will show Voyager plasma observations that demonstrate presence of a suprathermal ion component within Saturn's outer magnetosphere. The Voyager LECP data also reported the presence of inward diffusing energetic ions from the outer magnetosphere of Saturn, which could have an N+ contribution. If so, when one conserves the first and second adiabatic invariant the N+ ions will have energies in excess of 100 keV at Dione's L shell and greater than 400 keV at Enceladus' L shell. Energetic charged particle radial diffusion coefficients are also used to constrain the model results. But, one must also consider the solar wind as another important source of keV ions, in the form of protons and alpha particles, for Saturn's outer magnetosphere. Initial estimates indicate that a solar wind source could dominate in the outer magnetosphere, but various required parameters for this estimate are highly uncertain and will have to await Cassini results for confirmation. We show that satellite sweeping and charged particle precipitation within the middle and outer magnetosphere will tend to enrich N+ ions relative to protons within Saturn's inner magnetosphere as they diffuse radially inward for radial diffusion coefficients that do not violate observations. Charge exchange reactions within the inner magnetosphere can be an important loss mechanism for O+ ions, but to a lesser degree for N+ ions. Initial LECP results using composition data at energies greater than 200 keV/nucl., showed that heavy ions within Saturn's inner magnetosphere dominated over protons, but that contrary to original suggestions that these ions were O+ , we now argue that they are instead N+ ions. With energetic N+ ions bombarding the icy satellite surfaces chemical reactions can occur at the end of the ion tracks and produce nitrogen oxides or other nitrogen containing molecules such that the radiology within the icy surfaces is driven by the impacting energetic nitrogen ions. These can accumulate over the lifetime of the Saturn system.

Knowledge Exchange between Poland and Vietnam in Mining and Geology - the Status Quo and Future Development

NASA Astrophysics Data System (ADS)

Nguyen, Nga; Pham, Nguyet

2018-03-01

From the beginning of the 21st century, knowledge exchange between Poland and Vietnam in mining and geology has been focusing in technology, education and training. Since years, Polish academic and commercial partners have been developing a close collaboration with Vietnam National Coal - Mineral Industries Holding Corporation Limited. Major outcomes of the collaboration are installations and operation of mining equipments and machines in Vietnamese mining companies, and excellent training programs for graduate and post graduate students and mining staff for both countries, etc. From aspects of knowledge management in globalization, the article highlights the outstanding outcomes of knowledge exchanges between the two countries, outlines cultural and economic challenges for the exchange and proposes some improvement in the future.

Hitomi Constraints on the 3.5 keV Line in the Perseus Galaxy Cluster

DOE PAGES

Aharonian, F. A.; Akamatsu, H.; Akimoto, F.; ...

2017-03-03

High-resolution X-ray spectroscopy with Hitomi was expected to resolve the origin of the faint unidentifiedmore » $$E\\approx 3.5\\,\\mathrm{keV}$$ emission line reported in several low-resolution studies of various massive systems, such as galaxies and clusters, including the Perseus cluster. We have analyzed the Hitomi first-light observation of the Perseus cluster. The emission line expected for Perseus based on the XMM-Newton signal from the large cluster sample under the dark matter decay scenario is too faint to be detectable in the Hitomi data. However, the previously reported 3.5 keV flux from Perseus was anomalously high compared to the sample-based prediction. We find no unidentified line at the reported high flux level. Taking into account the XMM measurement uncertainties for this region, the inconsistency with Hitomi is at a 99% significance for a broad dark matter line and at 99.7% for a narrow line from the gas. We do not find anomalously high fluxes of the nearby faint K line or the Ar satellite line that were proposed as explanations for the earlier 3.5 keV detections. We do find a hint of a broad excess near the energies of high-n transitions of S xvi ($$E\\simeq 3.44\\,\\mathrm{keV}$$ rest-frame)—a possible signature of charge exchange in the molecular nebula and another proposed explanation for the unidentified line. While its energy is consistent with XMM pn detections, it is unlikely to explain the MOS signal. In conclusion, a confirmation of this interesting feature has to wait for a more sensitive observation with a future calorimeter experiment.« less

Knowledge exchange processes in organizations and policy arenas: a narrative systematic review of the literature.

PubMed

Contandriopoulos, Damien; Lemire, Marc; Denis, Jean-Louis; Tremblay, Emile

2010-12-01

This article presents the main results from a large-scale analytical systematic review on knowledge exchange interventions at the organizational and policymaking levels. The review integrated two broad traditions, one roughly focused on the use of social science research results and the other focused on policymaking and lobbying processes. Data collection was done using systematic snowball sampling. First, we used prospective snowballing to identify all documents citing any of a set of thirty-three seminal papers. This process identified 4,102 documents, 102 of which were retained for in-depth analysis. The bibliographies of these 102 documents were merged and used to identify retrospectively all articles cited five times or more and all books cited seven times or more. All together, 205 documents were analyzed. To develop an integrated model, the data were synthesized using an analytical approach. This article developed integrated conceptualizations of the forms of collective knowledge exchange systems, the nature of the knowledge exchanged, and the definition of collective-level use. This literature synthesis is organized around three dimensions of context: level of polarization (politics), cost-sharing equilibrium (economics), and institutionalized structures of communication (social structuring). The model developed here suggests that research is unlikely to provide context-independent evidence for the intrinsic efficacy of knowledge exchange strategies. To design a knowledge exchange intervention to maximize knowledge use, a detailed analysis of the context could use the kind of framework developed here. © 2010 Milbank Memorial Fund. Published by Wiley Periodicals Inc.

Knowledge Exchange Processes in Organizations and Policy Arenas: A Narrative Systematic Review of the Literature

PubMed Central

Contandriopoulos, Damien; Lemire, Marc; Denis, Jean-Louis; Tremblay, Émile

2010-01-01

Context: This article presents the main results from a large-scale analytical systematic review on knowledge exchange interventions at the organizational and policymaking levels. The review integrated two broad traditions, one roughly focused on the use of social science research results and the other focused on policymaking and lobbying processes. Methods: Data collection was done using systematic snowball sampling. First, we used prospective snowballing to identify all documents citing any of a set of thirty-three seminal papers. This process identified 4,102 documents, 102 of which were retained for in-depth analysis. The bibliographies of these 102 documents were merged and used to identify retrospectively all articles cited five times or more and all books cited seven times or more. All together, 205 documents were analyzed. To develop an integrated model, the data were synthesized using an analytical approach. Findings: This article developed integrated conceptualizations of the forms of collective knowledge exchange systems, the nature of the knowledge exchanged, and the definition of collective-level use. This literature synthesis is organized around three dimensions of context: level of polarization (politics), cost-sharing equilibrium (economics), and institutionalized structures of communication (social structuring). Conclusions: The model developed here suggests that research is unlikely to provide context-independent evidence for the intrinsic efficacy of knowledge exchange strategies. To design a knowledge exchange intervention to maximize knowledge use, a detailed analysis of the context could use the kind of framework developed here. PMID:21166865

Complementary knowledge sharing: Experiences of nursing students participating in an educational exchange program between Madagascar and Norway.

PubMed

Tjoflåt, Ingrid; Razaonandrianina, Julie; Karlsen, Bjørg; Hansen, Britt Sætre

2017-02-01

To describe how Malagasy and Norwegian nursing students experience an educational exchange program in Madagascar. Previous studies show that nursing students participating in an educational exchange program enhanced their cultural knowledge and experienced personal growth. However, few studies have described two-way exchange programs, including experiences from both the hosts' and the guest students' perspectives. This study applies a descriptive qualitative design. Data were collected in 2015 by means of five semi-structured interviews with Malagasy students and two focus group interview sessions with Norwegian students. They were analysed using qualitative content analysis. The study was conducted in Madagascar. The data analyses revealed one main theme and two sub-themes related to the Malagasy and Norwegian nursing students' experiences. Main theme: complementary knowledge sharing; sub-themes: (1) learning from each other and (2) challenges of working together. The findings indicate that both the Malagasy and Norwegian nursing students experienced the exchange program as valuable and essential in exchanging knowledge. They also highlighted challenges, linked mainly to language barriers and the lack of available resources. Copyright © 2016 Elsevier Ltd. All rights reserved.

Creating Sustainable Cities through Knowledge Exchange: A Case Study of Knowledge Transfer partnerships

ERIC Educational Resources Information Center

Hope, Alex

2016-01-01

Purpose: The purpose of this paper is to examine the use of knowledge transfer partnership (KTP)as a means for universities to generate and exchange knowledge to foster sustainable cities and societies. Design/methodology/approach: This paper reports on a series of separate yet interrelated KTPs between a university and the local authority in the…

Measuring power loss due to radiation and charge exchange in MST

NASA Astrophysics Data System (ADS)

Waksman, Jeff; Chapman, Brett; Fiksel, Gennady; Nonn, Paul

2008-11-01

An array of photodiode-pyrobolometer pairs will be placed on MST to measure the spatial structure of the radiated power and charge exchange. Photodiodes (XUV detectors) measure photonic radiated power from about 10eV to 10keV, while pyrobolometers (thermal detectors) measure both photonic radiated power and power carried by charge-exchange neutrals. Compared to other thermal detectors, pyrobolometers have very good time resolution. To accurately calibrate the individual detectors, an electron gun producing a modulated square wave output has been set up to carefully calibrate each new pyrobolometer to be placed on MST. When viewing the MST plasma, subtraction of the data from the photodiode-pyrobolometer pairs allows one to determine the net power loss due to charge-exchange neutrals. These measurements are important in the calculation of ion energy balance, and it is potentially important in understanding the difference in the temperatures reached by majority and impurity ions during magnetic-reconnection ion-heating events. Since toroidal and poloidal asymmetries in charge exchange are possible, a distributed array of detector pairs will facilitate a better estimate of global power loss. Work supported by the U.S.D.O.E. .

On the detectability of key-MeV solar protons through their nonthermal Lyman-alpha emission

NASA Technical Reports Server (NTRS)

Canfield, R. C.; Chang, C. R.

1985-01-01

The intensity and timescale of nonthermal Doppler-shifted hydrogen L alpha photon emission as diagnostics of 10 keV to 10 MeV protons bombarding the solar chromosphere during flares are investigated. The steady-state excitation and ionization balance of the proton beam are determined, taking into account all important atomic interactions with the ambient chromosphere. For a proton energy flux comparable to the electron energy flux commonly inferred for large flares, L alpha wing intensities orders of magnitude larger than observed nonflaring values were found. Investigation of timescales for ionization and charge exchange leads researchers to conclude that over a wide range of values of mean proton energy and beam parameters, Doppler-shifted nonthermal L alpha emission is a useful observational diagnostic of the presence of 10 keV to 10 MeV superthermal proton beams in the solar flare chromosphere.

Anomalous decay f1(1285 )→π+π-γ in the Nambu-Jona-Lasinio model

NASA Astrophysics Data System (ADS)

Osipov, A. A.; Volkov, M. K.

2018-04-01

Using the Nambu-Jona-Lasinio model with the U (2 )×U (2 ) chiral symmetric effective four-quark interactions, we derive the amplitude of the radiative decay f1(1285 )→π+π-γ , find the decay width Γ (f1→π+π-γ )=346 keV and obtain the spectral dipion effective mass distribution. It is shown that in contrast to the majority of theoretical estimates (which consider the a1(1260 ) meson exchange as the dominant one), the most relevant contribution to this process is the ρ0-resonance exchange related with the triangle f1ρ0γ anomaly. The spectral function is obtained to be confronted with the future empirical data.

Offshore Energy Knowledge Exchange Workshop Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

none,

2012-04-12

A report detailing the presentations and topics discussed at the Offshore Energy Knowledge Exchange Workshop, an event designed to bring together offshore energy industry representatives to share information, best practices, and lessons learned.

Characterization of xenon ion and neutral interactions in a well-characterized experiment

NASA Astrophysics Data System (ADS)

Patino, Marlene I.; Wirz, Richard E.

2018-06-01

Interactions between fast ions and slow neutral atoms are commonly dominated by charge-exchange and momentum-exchange collisions, which are important to understanding and simulating the performance and behavior of many plasma devices. To investigate these interactions, this work developed a simple, well-characterized experiment that accurately measures the behavior of high energy xenon ions incident on a background of xenon neutral atoms. By using well-defined operating conditions and a simple geometry, these results serve as canonical data for the development and validation of plasma models and models of neutral beam sources that need to ensure accurate treatment of angular scattering distributions of charge-exchange and momentum-exchange ions and neutrals. The energies used in this study are relevant for electric propulsion devices ˜1.5 keV and can be used to improve models of ion-neutral interactions in the plume. By comparing these results to both analytical and computational models of ion-neutral interactions, we discovered the importance of (1) accurately treating the differential cross-sections for momentum-exchange and charge-exchange collisions over a large range of neutral background pressures and (2) properly considering commonly overlooked interactions, such as ion-induced electron emission from nearby surfaces and neutral-neutral ionization collisions.

Genetics Home Reference: sitosterolemia

MedlinePlus

... Sitosterolemia ClinicalTrials.gov (1 link) ClinicalTrials.gov Scientific Articles on PubMed (1 link) PubMed OMIM (1 link) SITOSTEROLEMIA Sources for This Page Berge KE. Sitosterolemia: a gateway to new knowledge about cholesterol metabolism. Ann Med. 2003;35(7):502-11. Review. ...

The use of conferencing technologies to support drug policy group knowledge exchange processes: an action case approach.

PubMed

Househ, Mowafa Said; Kushniruk, Andre; Maclure, Malcolm; Carleton, Bruce; Cloutier-Fisher, Denise

2011-04-01

To describe experiences, lessons and the implications related to the use of conferencing technology to support three drug policy research groups within a three-year period, using the action case research method. An action case research field study was executed. Three different drug policy groups participated: research, educator, and decision-maker task groups. There were a total of 61 participants in the study. The study was conducted between 2004 and 2007. Each group used audio-teleconferencing, web-conferencing or both to support their knowledge exchange activities. Data were collected over three years and consisted of observation notes, interviews, and meeting transcripts. Content analysis was used to analyze the data using NIVIO qualitative data analysis software. The study found six key lessons regarding the impact of conferencing technologies on knowledge exchange within drug policy groups. We found that 1) groups adapt to technology to facilitate group communication, 2) web-conferencing communication is optimal under certain conditions, 3) audio conferencing is convenient, 4) web-conferencing forces group interactions to be "within text", 5) facilitation contributes to successful knowledge exchange, and 6) technology impacts information sharing. This study highlights lessons related to the use of conferencing technologies to support distant knowledge exchange within drug policy groups. Key lessons from this study can be used by drug policy groups to support successful knowledge exchange activities using conferencing technologies. 2010 Elsevier Ireland Ltd. All rights reserved.

Chromosomal intrachanges induced by swift iron ions

NASA Astrophysics Data System (ADS)

Horstmann, M.; Durante, M.; Johannes, C.; Obe, G.

We measured the induction of structural aberrations in human chromosome 5 induced by iron ions using the novel technique of multicolor banding in situ hybridization (mBAND). Human lymphocytes isolated from whole blood were exposed in vitro to 500 MeV/n (LET = 200 keV/μm, doses 1 or 4 Gy) Fe nuclei at the HIMAC accelerator in Chiba (Japan). Chromosomes were prematurely condensed by calyculin A after 48 h in culture and slides were painted by mBAND. We found a frequency of 0.11 and 0.57 residual breakpoints per chromosome 5 after 1 and 4 Gy Fe-ions, respectively. Inter-chromosomal exchanges were the prevalent aberration type measured at both doses, followed by terminal deletions, and by intra-chromosomal exchanges. Among intra-chromosomal exchanges, intra-arm events were more frequent than inter-arm, but a significant number of intra-changes was associated to inter-changes involving the same chromosome after 4 Gy of iron ions. These events show that the complexity of chromosomal exchanges induced by heavy ions can be higher than expected by previous FISH studies.

Distinguishing 3He and 4He with the Electron Proton Telescope (EPT) on Solar Orbiter

NASA Astrophysics Data System (ADS)

Boden, S.; Kulkarni, S. R.; Steinhagen, J.; Tammen, J.; Martin-Garcia, C.; Wimmer-Schweingruber, R. F.; Boettcher, S. I.; Seimetz, L.; Ravanbakhsh, A.; Elftmann, R.; Schuster, B.; Kulemzin, A.; Kolbe, S.; Mahesh, Y.; Knieriem, V.; Yu, J.; Kohler, J.; Panitzsch, L.; Terasa, C.; Boehm, E.; Rodriguez-Pacheco, J.; Prieto, M.; Gomez-Herrero, R.

2015-12-01

The Electron Proton Telescope (EPT) is one of the sensors of the Energetic Particle Detector (EPD) for the Solar Orbiter mission, which will provide key measurements to address particle acceleration at and near the Sun. The EPD suite consists of four different sensors (STEP, SIS, EPT and HET) which together will resolve the energetic particle spectrum from 2 keV to 20 MeV for electrons, 3 keV to 100 MeV for protons and circa 100 keV/nuc to 100 MeV/nuc for heavier ions.EPT itself is primarily designed to cleanly separate and measure electrons in the energy range from 20 - 400 keV and protons from 20 - 7000 keV. To achieve this, EPT uses two back-to-back solid state detectors with a magnet system to deflect electrons on one side and a Polyimide foil to stop protons below ~400 keV on the other side. The two detectors then serve as each other's anti-coincidence. Additionally this setup also allows us to measure penetrating particles with deposited energies in the 1 MeV to 40 MeV range. Looking at the ratio of deposited energy in the two detectors versus total deposited energy allows us to differentiate between protons and alpha particles. Distinguishing 3He from 4He will be challenging, but possible provided good knowledge of the instrument, high-fidelity modeling and a precise calibration of EPT. Here, we will present feasibility studies leading to a determination of the 3He / 4He ratio with EPT.

Structural approaches to knowledge exchange: comparing practices across five centres of excellence in public health.

PubMed

Van der Graaf, P; Francis, O; Doe, E; Barrett, E; O'Rorke, M; Docherty, G

2018-03-01

In 2008, five UKCRC Public Health Research Centres of Excellence were created to develop a coordinated approach to policy and practice engagement and knowledge exchange. The five Centres have developed their own models and practices for achieving these aims, which have not been compared in detail to date. We applied an extended version of Saner's model for the interface between science and policy to compare five case studies of knowledge exchanges, one from each centre. We compared these practices on three dimensions within our model (focus, function and type/scale) to identify barriers and facilitators for knowledge exchange. The case studies shared commonalities in their range of activities (type) but illustrated different ways of linking these activities (function). The Centres' approaches ranged from structural to more organic, and varied in the extent that they engaged internal audiences (focus). Each centre addressed policymakers at different geographical levels and scale. This article emphasizes the importance of linking a range of activities that engage policymakers at different levels, intensities and points in their decision-making processes to build relationships. Developing a structural approach to knowledge exchange activities in different contexts presents challenges of resource, implementation and evaluation.

Building knowledge development and exchange capacity in Canada: lessons from Youth Excel.

PubMed

Riley, B; Wong, K; Manske, S

2014-07-01

Youth Excel was a 3-year pan-Canadian initiative to advance youth health through improving knowledge development and exchange (KDE) capacity. KDE capacity refers to an improvement cycle linking evidence and action. Capacities include local surveillance of youth behaviours; knowledge exchange; skills, resources and a supportive environment to use knowledge; and evaluation. Interviews were conducted with Youth Excel members, including 7 provincial teams and 2 national organizations. Interviews explored participant experiences with building KDE capacity. Local surveillance systems were considered the backbone to KDE capacity, strengthened by co-ordinating surveys within and across jurisdictions and using common indicators and measures. The most effective knowledge exchange included tailored products and opportunities for dialogue and action planning. Evaluation is the least developed KDE component. Building KDE capacity requires frequent dialogue, mutually beneficial partnerships and trust. It also requires attention to language, vision, strategic leadership and funding. Youth Excel reinforces the need for a KDE system to improve youth health that will require new perspectives and sustained commitment from individual champions and relevant organizations.

“Tertius gaudens”: germplasm exchange networks and agroecological knowledge among home gardeners in the Iberian Peninsula

PubMed Central

2013-01-01

Background The idea that knowledge flows through social networks is implicit in research on traditional knowledge, but researchers have paid scant attention to the role of social networks in shaping its distribution. We bridge those two bodies of research and investigate a) the structure of network of exchange of plant propagation material (germplasm) and b) the relation between a person’s centrality in such network and his/her agroecological knowledge. Methods We study 10 networks of germplasm exchange (n = 363) in mountain regions of the Iberian Peninsula. Data were collected through participant observation, semi-structured interviews, and a survey. Results The networks display some structural characteristics (i.e., decentralization, presence of external actors) that could enhance the flow of knowledge and germplasm but also some characteristics that do not favor such flow (i.e., low density and fragmentation). We also find that a measure that captures the number of contacts of an individual in the germplasm exchange network is associated with the person’s agroecological knowledge. Conclusion Our findings highlight the importance of social relations in the construction of traditional knowledge. PMID:23883296

Expected charge states of energetic ions in the magnetosphere

NASA Technical Reports Server (NTRS)

Spjeldvik, W. N.

1979-01-01

Major developments in magnetospheric heavy ion physics during the period 1974-1977 are reviewed with emphasis on charge state aspects. Particular attention is given to the high energy component at energies above tens of keV per ion. Also considered are charge exchange processes with application to the inner magnetosphere, a comparison between theory and measurements, and a survey of heavy ion and charge state observations in the outer magnetosphere, magnetosheath and the surrounding space.

Diffusion studies with synchrotron Mössbauer spectroscopy

NASA Astrophysics Data System (ADS)

Jackson, J. M.

2011-12-01

Knowledge of diffusion properties is critical for understanding many physical and chemical processes in planetary interiors. For example, diffusion behavior provides constraints on chemical exchange and viscosity. Nuclear resonances open the window for observing diffusion properties under the extreme conditions that exist deep inside the Earth. Synchrotron Mössbauer spectroscopy (viz. nuclear forward scattering) makes use of synchrotron radiation coherently scattered in the forward direction after nuclear resonant excitation. The decay of the forward-scattered radiation is faster when atoms move on the time scale of the excited-state lifetime because of a loss of coherence. Such diffusion-activated processes lead to accelerated decay and line broadening in the measured signal. In the case of the Mössbauer active isotope 57Fe, the nuclear resonance at 14.4 keV has a natural lifetime of 141 ns. Therefore, one can observe diffusion events ranging from approximately one-sixth to 100 times the natural lifetime of 57Fe, which corresponds to diffusion coefficients of 10-16 and 10-13 m2/s, respectively and a two to three order of magnitude range of suitability. In this contribution, we will describe such measurements that access the microscopic details of the diffusion process for iron-bearing phases.

Semantic Modeling of Requirements: Leveraging Ontologies in Systems Engineering

ERIC Educational Resources Information Center

Mir, Masood Saleem

2012-01-01

The interdisciplinary nature of "Systems Engineering" (SE), having "stakeholders" from diverse domains with orthogonal facets, and need to consider all stages of "lifecycle" of system during conception, can benefit tremendously by employing "Knowledge Engineering" (KE) to achieve semantic agreement among all…

Measurement of differential cross section of D(3He,p)4He from 0.8 MeV to 3.6 MeV

NASA Astrophysics Data System (ADS)

Zhu, J. P.; Xiao, X.; Yan, S.; Gao, Y.; Xue, J. M.; Wang, Y. G.

2017-12-01

Precise knowledge of the nuclear reaction cross-section is crucial for nuclear reaction analysis methods and its applications. In order to apply nuclear reaction analysis methods to Plasma Facing Materials studies on 4.5 MV electrostatic accelerator at Peking University, differential cross-section for d(3He,p) α at several backward angles was measured with a relative error about ± 6.2 % , gives detailed information at the laboratory angle of 135° from 800 keV to 3600 keV, as well as a rough angular distribution from 130° to 160°.

Universities and the Public Good: A Review of Knowledge Exchange Policy and Related University Practice in Australia

ERIC Educational Resources Information Center

Cuthill, Michael; O'Shea, Éidín; Wilson, Bruce; Viljoen, Pierre

2014-01-01

Australian policy relating to knowledge exchange has never been well articulated, notwithstanding that the nexus between knowledge, engagement and higher education in Australia has been on the national agenda for several decades (Grattan Institute, 2013). In universities, this policy deficit is reflected in a lack of project management and…

"Actually, I Wanted to Learn": Study-Related Knowledge Exchange on Social Networking Sites

ERIC Educational Resources Information Center

Wodzicki, Katrin; Schwammlein, Eva; Moskaliuk, Johannes

2012-01-01

Social media open up multiple options to add a new dimension to learning and knowledge processes. Particularly, social networking sites allow students to connect formal and informal learning settings. Students can find like-minded people and organize informal knowledge exchange for educational purposes. However, little is known about in which way…

Implementing family nursing: how do we translate knowledge into clinical practice? Part II: The evolution of 20 years of teaching, research, and practice to a Center of Excellence in Family Nursing.

PubMed

Duhamel, Fabie

2010-02-01

The author's reflections on knowledge transfer/translation highlight the importance of the circular process between science and practice knowledge, leading to the notion of "knowledge exchange." She addresses the dilemmas of translating knowledge into clinical practice by describing her academic contributions to knowledge exchange within Family Systems Nursing (FSN). Teaching and research strategies are offered that address the circularity between science and practice knowledge. The evolution of 20 years of teaching, research, and clinical experience has resulted in the recent creation of a Center of Excellence in Family Nursing at the University of Montreal. The three main objectives of the Center uniquely focus on knowledge exchange by providing (a) a training context for skill development for nurses specializing in FSN, (b) a research milieu for knowledge "creation" and knowledge "in action" studies to further advance the practice of FSN, and (c) a family healing setting to support families who experience difficulty coping with health issues.

Charge exchange collisions of slow C6 + with atomic and molecular H

NASA Astrophysics Data System (ADS)

Saha, Bidhan C.; Guevara, Nicolais L.; Sabin, John R.; Deumens, Erik; Öhrn, Yngve

2016-04-01

Charge exchange in collisions of C6+ ions with H and H2 is investigated theoretically at projectile energies 0.1 < E < 10 keV/amu, using electron nuclear dynamics (END) - a semi-classical approximation which not only includes electron translation factors for avoiding spurious couplings but also employs full dynamical trajectories to treat nuclear motions. Both the total and partial cross sections are reported for the collision of C6+ ions with atomic and molecular hydrogen. A comparison with other theoretical and experimental results shows, in general good agreement except at very low energy, considered here. For H2, the one- and two-electron charge exchange cross sections are calculated and compared with other theoretical and experimental results. Small but non-negligible isotope effects are found at the lowest energy studied in the charge transfer of C6+ with H. In low energy region, it is observed that H2 has larger isotope effects than H atom due to the polarizability effect which is larger than the mass effect.

Multiplet exchange Auger transitions following resonant Auger decays in Ne 1s photoexcitation

NASA Astrophysics Data System (ADS)

Tamenori, Yusuke; Suzuki, Isao H.

2014-07-01

Secondary electron emission with very low kinetic energy (KE) has been measured in the Ne 1s photoexcitation region. A new decay channel for Auger transitions following Ne 1s to 3p excitation has been identified using a two-dimensional mapping technique, in which slow Auger electron signals are displayed as functions of electron kinetic energy and photon energy. Electrons with about 0.68 eV KEs have been ascribed to multiplet exchange Auger electrons from the 2p-2(1S)3d state. This state is formed through the resonant Auger transition from the 1s-13p state, in which the excited 3p electron changes its azimuthal quantum number. Another cascade Auger decay of multiplet exchanging was found as electron emission of about 2.0 eV KEs; 2p-2(1S)4p → 2p-2(3P) + e-. Several cascade decays were found to occur via the photoexcitation into 1s-14p and 1s-15p states.

The formation of excited atoms during charge exchange between hydrogen ions and alkali atoms. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Nieman, R. A.

1971-01-01

The charge exchange cross sections for protons and various alkali atoms are calculated using the classical approximation of Gryzinski. It is assumed that the hydrogen atoms resulting from charge exchange exist in all possible excited states. Charge transfer collisions between protons and potassium as well as protons and sodium atoms are studied. The energy range investigated is between 4 and 30 keV. The theoretical calculations of the capture cross section and the cross section for the creation of metastable 2S hydrogen are compared to experimental values. Good quantitative agreement is found for the capture cross section but only qualitative agreement for the metastable cross section. Analysis of the Lyman alpha window in molecular oxygen suggests that measured values of the metastable cross section may be in error. Thick alkali target data are also presented. This allows the determination of the total electron loss cross section. Finally, some work was done with H2(+).

Inference of the ring current ion composition by means of charge exchange decay

NASA Technical Reports Server (NTRS)

Smith, P. H.; Hoffman, R. A.; Bewtra, N. K.

1981-01-01

The analysis of data from the Explorer 45 (S3-A) electrostatic analyzer in the energy range 5-30 keV has provided some new results on the ring current ion composition. It has been well established that the storm time ring current has a decay time of several days, during which the particle fluxes decrease nearly monotonically. By analyzing the measured ion fluxes during the several day storm recovery period and assuming that beside hydrogen other ions were present and that the decays were exponential in nature, three separate lifetimes for the ions were established. These fitted decay lifetimes are in excellent agreement with the expected charge exchange decay lifetimes for H(+), O(+) and He(+) in the energy and L value range of the data.

Effect of the Edge Radial Electric Field on Neutral Particle Measurements

NASA Astrophysics Data System (ADS)

Guldi, C.; Heidbrink, W. W.; Beitzel, T. A.; Burrell, K. H.

2000-10-01

Neutral particle measurements in ASDEX were originally interpreted as evidence that the edge radial electric field Er changes gradually at the L-H transition.(W. Herrmann et al.), Phys. Rev. Lett. 75 (1995) 4401. We have relocated an analyzer to an orientation similar to the ASDEX analyzer: at the outer midplane viewing perpendicular ions midway between toroidal field coils. The electric field is measured by charge-exchange recombination and motional stark effect diagnostics. The passive charge exchange signal from the relocated analyzer is usually undetectable but, in discharges with large E_r, the flux of 5 keV neutrals can resemble ASDEX signals. The combined effects of ripple trapping and E_r× B_φ drifts(J.A. Heikkinen et al.), Plasma Phys. Contr. Fusion 40 (1998) 679. may explain the results.

Observation of Solar Wind Charge Exchange Emission from Exospheric Material in and Outside Earth's Magnetosheath

NASA Technical Reports Server (NTRS)

Snowden, S. L.; Collier, M. R.; Cravens, T.; Kuntz, K. D.; Lepri, S. T.; Robertson, I.; Tomas, L.

2008-01-01

A long XMM-Newton exposure is used to observe solar wind charge exchange (SWCX) emission from exospheric material in and outside Earth s magnetosheath. The light curve of the O VII (0.5-0.62 keV) band is compared with a model for the expected emission, and while the emission is faint and the light curve has considerable scatter, the correlation is significant to better than 99.9%. This result demonstrates the validity of the geocoronal SWCX emission model for predicting a contribution to astrophysical observations to a scale factor of order unity (1.36). The results also demonstrate the potential utility of using X-ray observations to study global phenomena of the magnetosheath which currently are only investigated using in situ measurements.

The Role of Community Trust and Altruism in Knowledge Sharing: An Investigation of a Virtual Community of Teacher Professionals

ERIC Educational Resources Information Center

Chen, Hsiu-Ling; Fan, Hsueh-Liang; Tsai, Chin-Chung

2014-01-01

The knowledge sharing process within a virtual community of teacher professionals is viewed as a social exchange process in that the knowledge sharing intention and behavior of individuals are influenced by the exchange relationship among members. However, relatively little research has focused on this approach to exploring the factors that…

Effect of embedded silver nanoparticles on refractive index of soda lime glass

NASA Astrophysics Data System (ADS)

Sonal, Sharma, Annu; Aggarwal, Sanjeev

2018-05-01

Silver glass nanocomposites were prepared by exposing silver doped soda lime glass slides obtained via ion-exchange reaction to a beam of 200 keV Argon ions (Ar+) at an off normal angle of 400 with doses of 5x1015 ions cm-2 and 1x1016 ions cm-2. These nanocomposites were further characterized using UV-visible spectrophotometer so as to study their transmission and reflection behavior and compute their refractive index and real and imaginary parts of dielectric function.

Developing Multimedia Supplementary Materials to Support Learning Beginning Level Chinese Characters

ERIC Educational Resources Information Center

Xu, Lisha

2017-01-01

Studies investigating beginner Chinese learners' character learning strategies found that learners considered orthographic knowledge the most useful factor (Ke, 1998; Shen, 2005). Orthographic recognition correlates with character identification and production and can be used by advanced learners to solve word identification problems (Everson,…

STUDYING FAINT ULTRA-HARD X-RAY EMISSION FROM AGN IN GOALS LIRGS WITH SWIFT/BAT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koss, Michael; Casey, Caitlin M.; Mushotzky, Richard

2013-03-10

We present the first analysis of the all-sky Swift Burst Alert Telescope (BAT) ultra-hard X-ray (14-195 keV) data for a targeted list of objects. We find that the BAT data can be studied at three-times-fainter limits than in previous blind detection catalogs based on prior knowledge of source positions and using smaller energy ranges for source detection. We determine the active galactic nucleus (AGN) fraction in 134 nearby (z < 0.05) luminous infrared galaxies (LIRGs) from the GOALS sample. We find that LIRGs have a higher detection frequency than galaxies matched in stellar mass and redshift at 14-195 keV andmore » 24-35 keV. In agreement with work at other wavelengths, the AGN detection fraction increases strongly at high IR luminosity with half of the high-luminosity LIRGs (50%, 6/12, log L{sub IR}/L{sub Sun} > 11.8) detected. The BAT AGN classification shows 97% (37/38) agreement with Chandra and XMM-Newton AGN classification using hardness ratios or detection of an iron K{alpha} line. This confirms our statistical analysis and supports the use of the Swift/BAT all-sky survey to study fainter populations of any category of sources in the ultra-hard X-ray band. BAT AGNs in LIRGs tend to show higher column densities with 40% {+-} 9% showing 14-195 keV/2-10 keV hardness flux ratios suggestive of high or Compton-thick column densities (log N{sub H} > 24 cm{sup -2}), compared to only 12% {+-} 5% of non-LIRG BAT AGNs. We also find that using specific energy ranges of the BAT detector can yield additional sources over total band detections with 24% (5/21) of detections in LIRGs at 24-35 keV not detected at 14-195 keV.« less

Assessments of the Veteran Medication Allergy Knowledge Gap and Potential Safety Improvements with the Veteran Health Information Exchange (VHIE).

PubMed

Pan, Eric; Botts, Nathan; Jordan, Harmon; Olinger, Lois; Donahue, Margaret; Hsing, Nelson

2016-01-01

The U.S. Department of Veterans Affairs (VA) Veteran Health Information Exchange (VHIE, formerly Virtual Lifetime Electronic Record, or VLER) had been deployed at all VA sites and used to exchange clinical information with private sector healthcare partners nationally. This paper examined VHIE's effect on allergy documentation. Review of all inbound VHIE transactions in FY14 showed that VHIE use was associated with a nearly eight-fold increase in allergy documentation rate. Preliminary manual document review further showed that VA and partners had shared knowledge of only 38% ofpatient allergies, while VA had exclusive knowledge of another 58% ofpatient allergies, and partners had exclusive knowledge of the last 5% of patient allergies. To our knowledge, this is the first study that examined the effect of HIE on allergy documentation.

Assessments of the Veteran Medication Allergy Knowledge Gap and Potential Safety Improvements with the Veteran Health Information Exchange (VHIE)

PubMed Central

Pan, Eric; Botts, Nathan; Jordan, Harmon; Olinger, Lois; Donahue, Margaret; Hsing, Nelson

2016-01-01

The U.S. Department of Veterans Affairs (VA) Veteran Health Information Exchange (VHIE, formerly Virtual Lifetime Electronic Record, or VLER) had been deployed at all VA sites and used to exchange clinical information with private sector healthcare partners nationally. This paper examined VHIE’s effect on allergy documentation. Review of all inbound VHIE transactions in FY14 showed that VHIE use was associated with a nearly eight-fold increase in allergy documentation rate. Preliminary manual document review further showed that VA and partners had shared knowledge of only 38% ofpatient allergies, while VA had exclusive knowledge of another 58% ofpatient allergies, and partners had exclusive knowledge of the last 5% of patient allergies. To our knowledge, this is the first study that examined the effect of HIE on allergy documentation. PMID:28269897

Higher Education Exchange 2006

ERIC Educational Resources Information Center

Brown, David W., Ed.; Witte, Deborah, Ed.

2006-01-01

Contributors to this issue of the Higher Education Exchange debate the issues around knowledge production, discuss the acquisition of deliberative skills for democracy, and examine how higher education prepares, or does not prepare, students for citizenship roles. Articles include: (1) "Foreword" (Deborah Witte); (2) "Knowledge,…

Boxing Clever: Using Shoeboxes to Support Home-School Knowledge Exchange

ERIC Educational Resources Information Center

Greenhough, Pamela; Scanlan, Mary; Feiler, Anthony; Johnson, David; Yee, Wan Ching; Andrews, Jane; Price, Alison; Smithson, Maggie; Hughes, Martin

2005-01-01

A key tenet of the Home-School Knowledge Exchange Project is that children's learning will be enhanced if the knowledge and experience that are to be found both at home and in school can be brought together. In this paper we explore ways of connecting home and school to support literacy learning at Key Stage 1, focusing on the home-to-school…

'Keep complaining til someone listens': Exchanges of tacit healthcare knowledge in online illness communities.

PubMed

Foster, Drew

2016-10-01

This article examines online exchanges of advice and knowledge among patients. It draws a distinction between explicit healthcare knowledge (i.e., facts about symptoms and treatments) and tacit healthcare knowledge (i.e., know-how about navigating the healthcare system). Based on analysis of message board interactions at a prominent online illness community, I find that patients routinely encourage one another to exercise agency strategically in clinical encounters by honing specific interactional skills. I isolate three major techniques that are advocated within the community (affect regulation, information management, and treatment persistence) and frame them as discrete examples of tacit healthcare knowledge. I argue that tacit healthcare knowledge constitutes a potentially potent source of empowerment for patients that can help them to receive their desired form of care from the health system and to negotiate relationships with medical professionals and institutions. I conclude by discussing how the concept of tacit healthcare knowledge further clarifies the wide variety of lay knowledge exchanged among patients online. Copyright © 2016 Elsevier Ltd. All rights reserved.

Circles of Confidence in Correspondence: Modeling Confidentiality and Secrecy in Knowledge Exchange Networks of Letters and Drawings in the Early Modern Period.

PubMed

van den Heuvel, Charles; Weingart, Scott B; Spelt, Nils; Nellen, Henk

2016-01-01

Science in the early modern world depended on openness in scholarly communication. On the other hand, a web of commercial, political, and religious conflicts required broad measures of secrecy and confidentiality; similar measures were integral to scholarly rivalries and plagiarism. This paper analyzes confidentiality and secrecy in intellectual and technological knowledge exchange via letters and drawings. We argue that existing approaches to understanding knowledge exchange in early modern Europe--which focus on the Republic of Letters as a unified entity of corresponding scholars--can be improved upon by analyzing multilayered networks of communication. We describe a data model to analyze circles of confidence and cultures of secrecy in intellectual and technological knowledge exchanges. Finally, we discuss the outcomes of a first experiment focusing on the question of how personal and professional/official relationships interact with confidentiality and secrecy, based on a case study of the correspondence of Hugo Grotius.

Absolute Charge Exchange Cross Sections for ^3He^2+ Collisions with ^4He and H_2

NASA Astrophysics Data System (ADS)

Mawhorter, R. J.; Greenwood, J.; Smith, S. J.; Chutjian, A.

2002-05-01

The JPL charge exchange beam-line(J.B. Greenwood, et al., Phys. Rev A 63), 062707 (2001) was modified to increase the forward acceptance angle and enable the measurement of total charge-exchange cross sections for slow, light, highly-charged ion collisions with neutral targets(R. E. Olson and M. Kimura, J. Phys. B 15), 4231 (1982). Data are presented for single charge exchange cross sections for ^3He^2+ nuclei scattered by ^4He and H2 in the energy range 0.33-4.67 keV/amu. For both targets there is good agreement with Kusakabe, et al.(T. Kusakabe, et al., J. Phys. Soc. Japan 59), 1218 (1990). Angular collection is studied by a comparison with differential measurements(D. Bordenave-Montesquieu and R. Dagnac, J. Phys. B 27), 543 (1994), as well as with earlier JPL results(J.B. Greenwood, et al., Ap. J. 533), L175 (2000), ibid. 529, 605 (2000) using heavier projectiles and targets. This work was carried out at JPL/Caltech, and was supported through contract with NASA. RJM thanks the NRC for a Senior Associateship at JPL.

The role of charge-exchange cross-section for pickup protons and neutrals in the inner heliosheath

NASA Astrophysics Data System (ADS)

Chalov, S. V.

2018-06-01

The process of deceleration of the solar wind downstream of the termination shock is studied on the basis of a one-dimensional multi-component model. It is assumed that the solar wind consists of thermal protons, electrons and interstellar pickup protons. The protons interact with interstellar hydrogen atoms by charge-exchange. Two cases are considered. In the first one, the charge-exchange cross-section for thermal protons and hydrogen atoms is the same as for pickup protons and atoms. Under this condition, there is a strong dependence of the solar wind velocity on the downstream temperature of pickup protons. When the proton temperature is close to 10 keV, the change in the velocity with the distance from the termination shock is similar to that measured on the Voyager 1 spacecraft: linear velocity decrease is accompanied by an extended transition region with near-zero velocity. However, with a more careful approach to the choice of the charge-exchange cross-section, the situation changes dramatically. The strong dependence of the solar wind speed on the pickup proton temperature disappears and the transition region in the heliosheath disappears as well, at least at reasonable distances from the TS.

Ring current proton decay by charge exchange

NASA Technical Reports Server (NTRS)

Smith, P. H.; Hoffman, R. A.; Fritz, T.

1975-01-01

Explorer 45 measurements during the recovery phase of a moderate magnetic storm have confirmed that the charge exchange decay mechanism can account for the decay of the storm-time proton ring current. Data from the moderate magnetic storm of 24 February 1972 was selected for study since a symmetrical ring current had developed and effects due to asymmetric ring current losses could be eliminated. It was found that after the initial rapid decay of the proton flux, the equatorially mirroring protons in the energy range 5 to 30 keV decayed throughout the L-value range of 3.5 to 5.0 at the charge exchange decay rate calculated by Liemohn. After several days of decay, the proton fluxes reached a lower limit where an apparent equilibrium was maintained, between weak particle source mechanisms and the loss mechanisms, until fresh protons were injected into the ring current region during substorms. While other proton loss mechanisms may also be operating, the results indicate that charge exchange can entirely account for the storm-time proton ring current decay, and that this mechanism must be considered in all studies involving the loss of proton ring current particles.

Cross Section Measurements of the 76Ge (n ,n' γ) Reaction

NASA Astrophysics Data System (ADS)

Crider, B. P.; Peters, E. E.; Prados-Estévez, F. M.; Ross, T. J.; McEllistrem, M. T.; Yates, S. W.; Vanhoy, J. R.

2013-10-01

Neutrinoless double-beta decay (0 νββ) is a topic of great current interest and, as such, is the focus of several experiments and international collaborations. Two of these experiments, Majorana and GERDA, are seeking evidence of 0 νββ in the decay of 76Ge, where the signal would appear as a sharp peak in the energy spectrum at the Q-value of the reaction plus a small amount of recoil energy, or 2039 keV. Due to the high sensitivity of such a measurement, knowledge of background lines is critical. A study of 76Ga β- decay into 76Ge revealed a 2040.70(25)-keV transition from the 3951.70(14)-keV level, which, if populated, could potentially be a background line of concern. In addition to β- decay from 76Ga, a potential population mechanism could be cosmic-ray-induced inelastic neutron scattering. Measurements of the neutron-induced cross section of the 3951.70-keV level have been performed utilizing the 76 Ge (n ,n' γ) reaction at the University of Kentucky at neutron energies ranging from 4.3 to 4.9 MeV. This material is based upon work is supported by the U.S. National Science Foundation under grant no. PHY-0956310.

Selection and collection of multi parameter physiological data for cardiac rhythm diagnostic algorithm development

NASA Astrophysics Data System (ADS)

Bostock, J.; Weller, P.; Cooklin, M.

2010-07-01

Automated diagnostic algorithms are used in implantable cardioverter-defibrillators (ICD's) to detect abnormal heart rhythms. Algorithms misdiagnose and improved specificity is needed to prevent inappropriate therapy. Knowledge engineering (KE) and artificial intelligence (AI) could improve this. A pilot study of KE was performed with artificial neural network (ANN) as AI system. A case note review analysed arrhythmic events stored in patients ICD memory. 13.2% patients received inappropriate therapy. The best ICD algorithm had sensitivity 1.00, specificity 0.69 (p<0.001 different to gold standard). A subset of data was used to train and test an ANN. A feed-forward, back-propagation network with 7 inputs, a 4 node hidden layer and 1 output had sensitivity 1.00, specificity 0.71 (p<0.001). A prospective study was performed using KE to list arrhythmias, factors and indicators for which measurable parameters were evaluated and results reviewed by a domain expert. Waveforms from electrodes in the heart and thoracic bio-impedance; temperature and motion data were collected from 65 patients during cardiac electrophysiological studies. 5 incomplete datasets were due to technical failures. We concluded that KE successfully guided selection of parameters and ANN produced a usable system and that complex data collection carries greater risk of technical failure, leading to data loss.

Stopping cross section of vanadium for H+ and He+ ions in a large energy interval deduced from backscattering spectra

NASA Astrophysics Data System (ADS)

Moro, M. V.; Bruckner, B.; Grande, P. L.; Tabacniks, M. H.; Bauer, P.; Primetzhofer, D.

2018-06-01

We have experimentally determined electronic stopping cross sections of vanadium for 50-2750 keV protons and for 250-6000 keV He ions by relative measurements in backscattering geometry. To check the consistency of the employed procedure we investigate how to define adequate reference stopping cross section data and chose different reference materials. To proof consistency of different reference data sets, an intercomparison is performed to test the reliability of the evaluation procedure for a wide range of energies. This process yielded consistent results. The resulting stopping cross section data for V are compared to values from the IAEA database, to the most commonly employed semi-empirical program SRIM, and to calculations according to CasP. For helium, our results show a significant deviation of up to 10% with respect to literature and to SRIM, but are in very good agreement with the CasP predictions, in particular when charge-exchange processes are included in the model.

Energetic neutral atoms from a trans-Europa gas torus at Jupiter.

PubMed

Mauk, B H; Mitchell, D G; Krimigis, S M; Roelof, E C; Paranicas, C P

2003-02-27

The space environments--or magnetospheres--of magnetized planets emit copious quantities of energetic neutral atoms (ENAs) at energies between tens of electron volts to hundreds of kiloelectron volts (keV). These energetic atoms result from charge exchange between magnetically trapped energetic ions and cold neutral atoms, and they carry significant amounts of energy and mass from the magnetospheres. Imaging their distribution allows us to investigate the structure of planetary magnetospheres. Here we report the analysis of 50-80 keV ENA images of Jupiter's magnetosphere, where two distinct emission regions dominate: the upper atmosphere of Jupiter itself, and a torus of emission residing just outside the orbit of Jupiter's satellite Europa. The trans-Europa component shows that, unexpectedly, Europa generates a gas cloud comparable in gas content to that associated with the volcanic moon Io. The quantity of gas found indicates that Europa has a much greater impact than hitherto believed on the structure of, and the energy flow within, Jupiter's magnetosphere.

Suzaku and XMM-Newton observations of the North Polar Spur: Charge exchange or ISM absorption?

NASA Astrophysics Data System (ADS)

Gu, Liyi; Mao, Junjie; Costantini, Elisa; Kaastra, Jelle

2016-10-01

By revisiting the Suzaku and XMM-Newton data of the North Polar Spur, we discovered that the spectra are inconsistent with the traditional model consisting of pure thermal emission and neutral absorption. The most prominent discrepancies are the enhanced O vii and Ne ix forbidden-to-resonance ratios, and a high O viii Lyβ line relative to other Lyman series. A collisionally ionized absorption model can naturally explain both features, while a charge exchange component can only account for the former. By including the additional ionized absorption, the plasma in the North Polar Spur can be described by a single-phase collisional ionization equilibrium (CIE) component with a temperature of 0.25 keV, and nitrogen, oxygen, neon, magnesium, and iron abundances of 0.4-0.8 solar. The abundance pattern of the North Polar Spur is well in line with those of the Galactic halo stars. The high nitrogen-to-oxygen ratio reported in previous studies can be migrated to the large transmission of the O viii Lyα line. The ionized absorber is characterized by a balance temperature of 0.17-0.20 keV and a column density of 3-5 × 1019 cm-2. Based on the derived abundances and absorption, we speculate that the North Polar Spur is a structure in the Galactic halo, so that the emission is mostly absorbed by the Galactic interstellar medium in the line of sight.

76 FR 28001 - Privacy Act of 1974; System of Records

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-13

..., Department of Defense. Deletion: K890.09 Enterprise Data and Global Exchange (EDGE) Knowledge Management Portal (March 21, 2006, 71 FR 14187). Reason: Enterprise Data and Global Exchange (EDGE) Knowledge....regulations.gov Follow the instructions for submitting comments. Mail: Federal Docket Management System Office...

Where the Grass Grows Again: Knowledge Exchange in the Sustainable Agriculture Movement.

ERIC Educational Resources Information Center

Hassanein, Neva; Kloppenburg, Jack R., Jr.

1995-01-01

Intensive rotational grazing by Wisconsin dairy farmers represents a local expression of the sustainable agriculture movement. Contrary to interpretations that view local knowledge in agriculture as idiosyncratic, these graziers use horizontal forms of organizing and information exchange to overcome the limits of personal experience and share…

Knowledge Exchange between Academia and the Third Sector

ERIC Educational Resources Information Center

Murdock, Alex; Shariff, Razia; Wilding, Karl

2013-01-01

This paper considers the different approaches to undertake knowledge exchange between academia and the third sector from three practitioner perspectives. London South Bank University (LSBU), as part of the Economic and Social Research Council (ESRC) and Third Sector Research Centre (TSRC) Social Enterprise Capacity Building Cluster (CBC), has been…

Investigating Knowledge Exchange amongst School Teachers, University Teacher Educators and Industry Partners

ERIC Educational Resources Information Center

Maher, Damian; Schuck, Sandy; Perry, Rachel

2017-01-01

This article reports on a study in which teachers, university teacher educators and a software company formed a learning community which provided a mechanism for knowledge exchange regarding pedagogical approaches using mobile technologies. The study employed an interpretivist methodology. The findings indicated that the collaboration promoted…

Effects of Organizational Trust on Organizational Learning and Creativity

ERIC Educational Resources Information Center

Jiang, Yi; Chen, Wen-Ke

2017-01-01

In the knowledge economy era, the competitive advantage of an enterprise is established on intangible resources and capability. Trust allows individuals acquiring and exchanging intellectual capitals, especially in ambiguous and uncertain situations, and knowledge exchange relies on the existence of trust. Different from past other industries,…

Knowledge Exchange with Sistema Scotland

ERIC Educational Resources Information Center

Allan, Julie; Moran, Nikki; Duffy, Celia; Loening, Gica

2010-01-01

This paper reports on a knowledge exchange project, funded by the Scottish Funding Council and undertaken by a group of researchers from three higher education institutions in Scotland and the project partner, Sistema Scotland. This newly established charity is attempting to implement a major programme of social change, developed in Venezuela,…

Characterization of adsorption sites on aggregate soil samples using synchrotron X-ray computerized microtomography.

PubMed

Altman, Susan J; Rivers, Mark L; Reno, Marissa D; Cygan, Randall T; McLain, Angela A

2005-04-15

Synchrotron-source X-ray computerized microtomography (CMT) was used to evaluate the adsorptive properties of aggregate soil samples. A linear relationship between measured mean mass attenuation coefficient (sigma) and mass fraction iron was generated by imaging mineral standards with known iron contents. On the basis of reported stoichiometries of the clay minerals and identifications of iron oxyhydroxides (1), we calculated the mass fraction iron and iron oxyhydroxide in the intergranular material. The mass fractions of iron were estimated to range from 0.17 to 0.22 for measurements made at 18 keV and from 0.18 to 0.21 for measurements made at 26 keV. One aggregate sample also contained regions within the intergranular material with mass fraction iron ranging from 0.29 to 0.31 and from 0.33 to 0.36 for the 18 and 26 keV measurements, respectively. The mass fraction iron oxyhydroxide ranged from 0.18 to 0.35 for the low-iron intergranular material and from 0.40 to 0.59 for the high-iron intergranular material. Using absorption edge difference imaging with CMT, we visualized cesium on the intergranular material, presumably because of adsorption and possible exchange reactions. By characterizing the mass fraction iron, the mass fraction iron oxyhydroxide, and the adsorptive capacity of these soil mineral aggregates, we provide information useful for conceptualization, development, and parametrization of transport models.

Non-invasive localization of organic matter in soil aggregates using SR-μCT

NASA Astrophysics Data System (ADS)

Peth, Stephan; Mordhorst, Anneka; Chenu, Claire; Uteau Puschmann, Daniel; Garnier, Patricia; Nunan, Naoise; Pot, Valerie; Beckmann, Felix; Ogurreck, Malte

2014-05-01

Knowledge of the location of soil organic matter (SOM) and its spatial association to soil structure is an important step in improving modeling approaches for simulating organic matter turnover processes. Advanced models for carbon mineralization are able to account for the 3D distribution of SOM which is assumed to influence mineralisation. However, their application is still limited by the fact that no method exists to non-invasively determine the 3D spatial distribution of SOM in structured soils. SR-based X-ray microtomography (SR-µCT) is an advanced and promising tool in gaining knowledge on the 3-dimensional organization of soil phases (minerals, organic matter, water, air) which on a voxel level could be implemented into spatially explicit models. However, since the contrast of linear attenuation coefficients of soil organic matter on the one hand and mineral components and water on the other hand are relatively low, especially when materials are finely dispersed, organic matter within the soil pore space is often not resolved in ordinary X-ray absorption contrast imaging. To circumvent this problem we have developed a staining procedure for organic matter using Osmium-tetroxide since Osmium is an element with an absorption edge at a higher X-ray energy level. Osmium is known from transmission electron microscopy analysis (TEM) to stain organic matter specifically and irreversibly while having an absorption edge at approximately 74 keV. We report on the application of a novel Osmium vapor staining method to analyze differences in organic matter content and identify small scale spatial distribution of SOM in soil aggregates. To achieve this we have taken soil aggregate samples (6-8 mm across) obtained from arable soils differing in soil management. Aggregate samples were investigated by synchrotron-based X-ray microtomography (SR-µCT) after staining the sample with Osmium-tetroxide (OsO4) vapor. We utilized the monochromatic X-ray beam to locate osmium bound to SOM in the stained soil aggregate samples by scanning the aggregates at different photon energies: 30 keV at which the attenuation contrast is optimal for distinguishing other soil constituents, 70 keV (below the absorption of osmium) and 78 keV (above the absorption edge of osmium). The results suggest that particulate organic matter, which was not visibly by scanning samples at energy levels optimal for resolving soil structure (30 keV), was identified after osmium staining and scanning the samples at energy levels just below (70 keV) and above (78 keV) the absorption edge of Osmium. Subtracting the images below from the images above the osmium edged we were able to isolate stained particulate organic matter which otherwise would have been wrongly interpreted as pore space without staining. Combining both pore space and organic matter distribution we are able to investigate the association of SOM with soil structure.

A neutral lithium beam source

NASA Astrophysics Data System (ADS)

Zhang, XiaoDong; Wang, ZhengMin; Hu, LiQun

1994-04-01

A low energy neutral lithium beam source with energy about 6 keV and a neutral beam equivalent current of 20 μA/cm2 has been developed in ASIPP in order to measure the density gradient and the fluctuations in the edge plasma of the HT-6M tokamak. In the source, lithium ions are extracted from a solid emitter (β-eucryptite), focused in a two-tube immersion lens, and neutralized in a charge-exchange cell with sodium. This source operates in pulsed mode. The pulse length is adjustable from 10 to 100 ms.

Evaluation of a Knowledge Translation and Exchange Platform to Advance Non-Communicable Disease Prevention

ERIC Educational Resources Information Center

Pettman, Tahna Lee; Armstrong, Rebecca; Waters, Elizabeth; Allender, Steven; Love, Penelope; Gill, Tim; Coveney, John; Boylan, Sinead; Booth, Sue; Bolton, Kristy; Swinburn, Boyd

2016-01-01

Coordinated systems are required to ensure evidence-informed practice and evaluation of community-based interventions (CBIs). Knowledge translation and exchange (KTE) strategies show promise, but these require evaluation. This paper describes implementation and evaluation of COOPS, a national KTE platform to support best practice in obesity…

Understanding Knowledge Sharing between IT Professionals--An Integration of Social Cognitive and Social Exchange Theory

ERIC Educational Resources Information Center

Tsai, Ming-Tien; Cheng, Nai-Chang

2012-01-01

The research includes various constructs based on social exchange theory and social cognitive theory. This study mainly explored the relationships among organisational justice, trust, commitment and knowledge-sharing cognition and verified their mediating effects through two variables of trust and commitment. A survey utilising a questionnaire was…

How to Enable Knowledge Exchange in "Second Life" in Design Education?

ERIC Educational Resources Information Center

Thomassen, Aukje; Rive, Pete

2010-01-01

The theory and lessons of knowledge exchange, in both a physical and virtual environment, suggest a framework for understanding the specific requirements for a digital design class in "Second Life". Through teaching and observing students who were asked to complete a machinima project, our research provided examples of the strengths and…

The embodied nurse: Interdisciplinary knowledge exchange between compassionate nursing and recent developments in embodied leadership studies.

PubMed

Koya, Kushwanth; Anderson, Jane; Sice, Petia

2017-12-01

To report a potential knowledge exchange between nursing studies and the results obtained from a study conducted into the attributes of embodied leadership. Leadership theories have been applied to evaluate, improve, and train nursing practitioners in several previous studies. However, leadership research has entered a new phase where the focus is to produce sustainable leaders through authenticity and compassion, the same two characteristics identified as being of most success in emergent nursing practice. There are few studies that have indicated a knowledge exchange between the latest developments in leadership studies and nursing. An exploratory and qualitative study. Between February 2012 - July 2012, a focused sample of 14 medical care professionals was interviewed across a chain of hospitals. The aim was to evaluate embodied leadership characteristics and understand the factors that contribute to the manifestation of these characteristics. The transcribed interviews were analysed using thematic analysis. Several factors that contribute to the characteristics of embodied leadership have been identified in the interviews and in subsequent literature searches on the characteristics and contributing factors found to be associated with nursing research. These could prompt a knowledge exchange. The results suggest common ground between nursing and contemporary leadership research in the exposition of behaviours; namely, being non-judgmental, listening actively, reflective practice and embracing uncertainty. Several implications can therefore be expected through the exchange of knowledge resulting from collaboration between researchers in the two disciplines. © 2017 John Wiley & Sons Ltd.

M-FISH Analysis of Chromosome Aberrations in Human Fibroblast Cells After In Vitro Exposure to Low- and High-LET Radiation

NASA Technical Reports Server (NTRS)

Wu, Honglu; Furusawa, Yoshiya; George, Kerry; Kawata, Tetsuya; Cucinotta, Francis

2002-01-01

The recently commercialized multiplex fluorescence in situ hybridization (m-FISH) technique, which allows human chromosomes to be painted in 24 different colors, was used to analyze chromosome aberrations in diploid human fibroblast cells after in vitro radiation exposure. Confluent flasks of a normal primary fibroblast cell line (AG 1522) were irradiated at high dose rates with either gamma rays or 200 MeV/nucleon Fe ions (LET = 440 keV/micron), incubated at 37 C for 24 hours after exposure, and subsequently subcultured. A chemically induced premature chromosome condensation technique was used to collect chromosome samples 32 hours after subculture. Results showed that the fraction of exchanges which were identified as complex, i.e. involving misrejoining of three or more DSB, were higher in the Fe-irradiated samples compared with the gamma-irradiated samples, as has been shown previously using FISH with one or two painted chromosomes . The ratios of complex/simple type exchanges were similar for samples irradiated with 0.7 Gy and 3 Gy of Fe ions, although exchanges involving five or more breaks were found only in 3 Gy irradiated samples. The fraction of incomplete exchanges was also higher in Fe- than gamma-irradiated samples. Data on the distribution of individual chromosome involvement in interchromosomal exchanges will be presented.

Energetic neutral particles from Jupiter and Saturn

NASA Astrophysics Data System (ADS)

Cheng, A. F.

1986-04-01

The Voyager 1 spacecraft has detected energetic neutral particles escaping from the magnetospheres of Jupiter and Saturn. These energetic neutrals are created in charge exchange reactions between radiation belt ions and ambient atoms or molecules in the magnetosphere. If the Io torus is assumed to be the dominant Jovian source region for energetic neutrals, the Voyager observations can be used to infer upper limits to the average ion intensities there below about 200 keV. No readily interpretable in-situ measurements are available in the Io torus at these energies. The middle and outer Jovian magnetospheres may also be a significant source of energetic neutrals. At Saturn, the observed neutral particle count rates are too high to be explained by charge exchange between fast protons and H atoms of the Titan torus. Most of the energetic neutrals may be produced by charge exchanges between heavy ions and a neutral cloud containing H2O in Saturn's inner magnetosphere. If so, the Voyager measurements of energetic neutral fluxes would be the first detected emissions from this region of Saturn's magnetosphere.

The effect of track structure on the induction of chromosomal aberrations in murine cells

NASA Technical Reports Server (NTRS)

Durante, M.; Cella, L.; Furusawa, Y.; George, K.; Gialanella, G.; Grossi, G.; Pugliese, M.; Saito, M.; Yang, T. C.

1998-01-01

PURPOSE: To measure chromosome aberrations in C3H 10T1/2 mouse fibroblasts using FISH painting at the first mitosis following exposure to 30 keV/microm hydrogen or neon ions. MATERIALS AND METHODS: Cells in plateau-phase were irradiated with 0.86 MeV protons at the TTT-3 Tandem accelerator in Naples (Italy), or with 400 MeV/n Ne ions at the HIMAC accelerator in Chiba (Japan). Colcemid-blocked cells were harvested at the first mitosis following exposure, and chromosome spreads were hybridized in situ with a fluorescein-labelled composite mouse DNA probe specific for chromosomes 2 and 8. RESULTS: Protons were more efficient than neon ions at the same LET in the induction of chromosome interchanges and breaks. Yields of complex exchanges were similar for both particles at the same dose, but protons produced mostly insertions, while with Ne exposure non-reciprocal exchanges were the most frequent complex-type exchange. CONCLUSIONS: Charged particles with the same LET produce different yields of chromosome aberrations, and some observed differences can be explained based on the available track-structure models.

The effect of track structure on the induction of chromosomal aberrations in murine cells.

PubMed

Durante, M; Cella, L; Furusawa, Y; George, K; Gialanella, G; Grossi, G; Pugliese, M; Saito, M; Yang, T C

1998-03-01

To measure chromosome aberrations in C3H 10T1/2 mouse fibroblasts using FISH painting at the first mitosis following exposure to 30 keV/microm hydrogen or neon ions. Cells in plateau-phase were irradiated with 0.86 MeV protons at the TTT-3 Tandem accelerator in Naples (Italy), or with 400 MeV/n Ne ions at the HIMAC accelerator in Chiba (Japan). Colcemid-blocked cells were harvested at the first mitosis following exposure, and chromosome spreads were hybridized in situ with a fluorescein-labelled composite mouse DNA probe specific for chromosomes 2 and 8. Protons were more efficient than neon ions at the same LET in the induction of chromosome interchanges and breaks. Yields of complex exchanges were similar for both particles at the same dose, but protons produced mostly insertions, while with Ne exposure non-reciprocal exchanges were the most frequent complex-type exchange. Charged particles with the same LET produce different yields of chromosome aberrations, and some observed differences can be explained based on the available track-structure models.

Powerful Radio Galaxies with Simbol-X: the Nuclear Environment

NASA Astrophysics Data System (ADS)

Torresi, E.; Grandi, P.; Malaguti, G.; Palumbo, G. G. C.; Bianchin, V.

2009-05-01

Fanaroff & Riley type II radio galaxies (FRII) are complex objects. In particular FRII Narrow Line Radio Galaxies (NLRG), optically classified as High Excitation Galaxies (HEG) show X-ray spectra very similar to their radio-quiet counterparts, the Seyfert 2 galaxies. They show 2-10 keV continua heavily obscured (NH~1023-24 cm-2) and intense FeKα lines, typical cold matter reprocessing features. Moreover recent Chandra and XMM-Newton observations suggest that the soft X-ray emission of HEG and Seyfert 2 have a common origin from photoionized gas, reinforcing the idea that not only their nuclear engine but also the circumnuclear gas (at least the warm phase) are similar. On the contrary, our knowledge of NLRG HEG above 10 keV is very poor when compared to brighter Seyfert 2. As a consequence, the physical properties of the cold phase of the circumnuclear gas (possibly linked to a dusty torus) are largely unknown. Thanks to its high sensitivity up to 80 keV, Simbol-X will provide very accurate spectra and will allow a direct comparison between the NLRG and Seyfert 2 cold environments.

Response of energetic particles to local magnetic dipolarization inside geosynchronous orbit

NASA Astrophysics Data System (ADS)

Motoba, T.; Ohtani, S.; Gkioulidou, M.; Takahashi, K.

2017-12-01

Magnetic field dipolarization and energetic particle injections are the most distinct phenomena observed in the inner magnetosphere during the substorm expansion phase. Compared to a wealth of knowledge about the phenomenology of magnetic dipolarizations and particle injections at/outside geosynchronous orbit (GEO), our understanding of them inside GEO remains incomplete because of a very limited number of previous studies. In the present study, we statistically examine the response of 1-1000 keV energetic particles to local magnetic dipolarization by performing a superposed epoch analysis of energetic particle fluxes with the zero epoch defined as the dipolarization onset times. Based on data from the Van Allen Probes tail seasons in 2012-2016, we identified a total of 97 magnetic dipolarization events which occurred closer to the magnetic equator (i.e., BH, which is antiparallel to the Earth's dipole axis, is the dominant component of the local magnetic field at least for 5 min before the onset). For major ion species (hydrogen, helium, and oxygen ions), the relative flux intensity to the pre-onset level increases at > 50 keV and decreases at < 30 keV. The hydrogen and helium ion fluxes in the hundreds of keV range sharply increase within a minute after the onset and then decay. Compared to the short-lived nature of hydrogen and helium ion flux enhancements, oxygen ion fluxes are enhanced more gradually (on the order of several minutes). The relative ion flux intensity and peak energy generally tend to increase for stronger dipolarization-related impulsive westward electric field. This suggests that the impulsive electric field is responsible for the energization and/or transport of energetic ions inside GEO. On the other hand, the electron flux enhancement first appears from several tens of keV to a few hundreds of keV, and then exhibits an inverse energy dispersion. For dipolarizations with strong impulsive westward electric fields, the relative electron flux intensity increases up to 5-10 times, in particular most significant at several tens of keV. This result suggests that the impulsive electric field acts as an efficient factor in the rapid energization of the tens-of-keV electrons. We also discuss how the response of energetic particles to dipolarization depends on MLT, radial distance, and pitch angle.

Ion energetics at Saturn's magnetosphere using Cassini/MIMI measurements: A simple model for the energetic ion integral moments

NASA Astrophysics Data System (ADS)

Dialynas, K.; Paranicas, C.; Roussos, E.; Krimigis, S. M.; Kane, M.; Mitchell, D. G.

2015-12-01

We present a composite analysis (H+ and O+) of energetic ion spectra and kappa distribution fits, using combined ion measurements from Charge Energy Mass Spectrometer (CHEMS, 3 to 236 keV/e), Low Energy Magnetospheric Measurements System (LEMMS, 0.024 < E < 18 MeV), and the Ion Neutral Camera (INCA, ~5.2 to >220 keV for H+). The modeled expressions of these energetic ion distributions are then used to obtain the four integral particle moments (from zeroth to 3rd moment: n, In, P, IE, i.e. Density, Integral number intensity, Pressure, Integral energy intensity) as well as the characteristic energy (EC=IE/In) of these ions as a function of Local Time and L-Shell. We find that a) protons dominate the energetic ion (>30 keV) integral number and energy intensity at all radial distances (L>5 Rs) and local times, while the H+ and O+ partial pressures and densities are comparable; b) the 12

SU-E-I-43: Photoelectric Cross Section Revisited

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haga, A; Nakagawa, K; Kotoku, J

2015-06-15

Purpose: The importance of the precision in photoelectric cross-section value increases for recent developed technology such as dual energy computed tomography, in which some reconstruction algorithms require the energy dependence of the photo-absorption in each material composition of human being. In this study, we revisited the photoelectric cross-section calculation by self-consistent relativistic Hartree-Fock (HF) atomic model and compared with that widely distributed as “XCOM database” in National Institute of Standards and Technology, which was evaluated with localdensity approximation for electron-exchange (Fock)z potential. Methods: The photoelectric cross section can be calculated with the electron wave functions in initial atomic state (boundmore » electron) and final continuum state (photoelectron). These electron states were constructed based on the selfconsistent HF calculation, where the repulsive Coulomb potential from the electron charge distribution (Hartree term) and the electron exchange potential with full electromagnetic interaction (Fock term) were included for the electron-electron interaction. The photoelectric cross sections were evaluated for He (Z=2), Be (Z=4), C (Z=6), O (Z=8), and Ne (Z=10) in energy range of 10keV to 1MeV. The Result was compared with XCOM database. Results: The difference of the photoelectric cross section between the present calculation and XCOM database was 8% at a maximum (in 10keV for Be). The agreement tends to be better as the atomic number increases. The contribution from each atomic shell has a considerable discrepancy with XCOM database except for K-shell. However, because the photoelectric cross section arising from K-shell is dominant, the net photoelectric cross section was almost insensitive to the different handling in Fock potential. Conclusion: The photoelectric cross-section program has been developed based on the fully self-consistent relativistic HF atomic model. Due to small effect on the Fock potential for K-shell electrons, the difference from XCOM database was limited: 1% to 8% for low-Z elements in 10keV-1MeV energy ranges. This work was partly supported by the JSPS Core-to-Core Program (No. 23003)« less

Linear attenuation coefficients of tissues from 1 keV to 150 keV

NASA Astrophysics Data System (ADS)

Böke, Aysun

2014-09-01

The linear attenuation coefficients and three interaction processes have been computed for liver, kidney, muscle, fat and for a range of x-ray energies from 1 keV to 150 keV. Molecular photoelectric absorption cross sections were calculated from atomic cross section data. Total coherent (Rayleigh) and incoherent (Compton) scattering cross sections were obtained by numerical integration over combinations of F2m(x) with the Thomson formula and Sm(x) with the Klein-Nishina formula, respectively. For the coherent (Rayleigh) scattering cross section calculations, molecular form factors were obtained from recent experimental data in the literature for values of x<1 Å-1 and from the relativistic modified atomic form factors for values of x≥1 Å-1. With the inclusion of molecular interference effects in the coherent (Rayleigh) scattering, more accurate knowledge of the scatter from these tissues will be provided. The number of elements involved in tissue composition is 5 for liver, 47 for kidney, 44 for muscle and 3 for fat. The results are compared with previously published experimental and theoretical linear attenuation coefficients. In general, good agreement is obtained. The molecular form factors and scattering functions and cross sections are incorporated into a Monte Carlo program. The energy distributions of x-ray photons scattered from tissues have been simulated and the results are presented.

Developing a geoscience knowledge framework for a national geological survey organisation

NASA Astrophysics Data System (ADS)

Howard, Andrew S.; Hatton, Bill; Reitsma, Femke; Lawrie, Ken I. G.

2009-04-01

Geological survey organisations (GSOs) are established by most nations to provide a geoscience knowledge base for effective decision-making on mitigating the impacts of natural hazards and global change, and on sustainable management of natural resources. The value of the knowledge base as a national asset is continually enhanced by the exchange of knowledge between GSOs as data and information providers and the stakeholder community as knowledge 'users and exploiters'. Geological maps and associated narrative texts typically form the core of national geoscience knowledge bases, but have some inherent limitations as methods of capturing and articulating knowledge. Much knowledge about the three-dimensional (3D) spatial interpretation and its derivation and uncertainty, and the wider contextual value of the knowledge, remains intangible in the minds of the mapping geologist in implicit and tacit form. To realise the value of these knowledge assets, the British Geological Survey (BGS) has established a workflow-based cyber-infrastructure to enhance its knowledge management and exchange capability. Future geoscience surveys in the BGS will contribute to a national, 3D digital knowledge base on UK geology, with the associated implicit and tacit information captured as metadata, qualitative assessments of uncertainty, and documented workflows and best practice. Knowledge-based decision-making at all levels of society requires both the accessibility and reliability of knowledge to be enhanced in the grid-based world. Establishment of collaborative cyber-infrastructures and ontologies for geoscience knowledge management and exchange will ensure that GSOs, as knowledge-based organisations, can make their contribution to this wider goal.

Knowledge transfer and exchange frameworks in health and their applicability to palliative care: scoping review protocol.

PubMed

Prihodova, Lucia; Guerin, Suzanne; Kernohan, W George

2015-07-01

To review knowledge transfer and exchange frameworks used in health, to analyse the core concepts of these frameworks and appraise their potential applicability to palliative care. Although there are over 60 different models of knowledge transfer and exchange designed for various areas of the fields of health care, many remain largely unrefined and untested. There is a lack of studies that create guidelines for scaling-up successful implementation of research findings and of proven models ensuring that patients have access to optimal health care, guided by current research. The protocol for this scoping review was devised according to the guidelines proposed by Arksey and O'Malley (2005) and Levac et al. (2010). The protocol includes decisions about the review objectives, inclusion criteria, search strategy, study selection, data extraction, quality assessment, data synthesis and plans for dissemination. The review will allow us to identify the currently used models of knowledge transfer and exchange in healthcare setting and analyse their applicability to the complex demands of palliative care. Results from this review will identify effective way of translating different types of knowledge to different PC providers and could be used in hospital, community and home based PC and future research. © 2015 John Wiley & Sons Ltd.

Taking Action for Looked after Children in School: A Knowledge Exchange Programme

ERIC Educational Resources Information Center

Carroll, Catherine; Cameron, Claire

2017-01-01

Promoting the Achievement of Looked After Children (PALAC) is a knowledge exchange programme that aims to support the development of practice in schools and to expand the evidence base to ultimately improve outcomes for children in care. Feedback on the first year of PALAC exceeded expectations, with practitioners using their projects to evaluate…

Observation of Solar Wind Charge Exchange Emission From Exospheric Material in and Outside Earth's Magnetosheath 2008 September 25

NASA Technical Reports Server (NTRS)

Snowden, S. L.; Collier, M. R.; Cravens, T.; Kuntz, K. D.; Lepri, S. T.; Robertson, I.; Tomas, L.

2009-01-01

A long XMM-Newton exposure is used to observe solar wind charge exchange (SWCX) emission from exospheric material in and outside Earth's magnetosheath. The light curve of the O vii (0.5-0.62 keV) band is compared with a model for the expected emission, and while the emission is faint and the light curve has considerable scatter, the correlation is significant to better than 99.9%. This result demonstrates the validity of the geocoronal SWCX emission model for predicting a contribution to astrophysical observations to a scale factor of order unity (1.5). In addition, an average value of the SWCX O vii emission from the magnetosheath over the observation of 2.6 +/- 0.5 LU is derived. The results also demonstrate the potential utility of using X-ray observations to study global phenomena of the magnetosheath which currently are only investigated using in situ measurements.

Soft x-ray emission from solar wind charge exchange in the laboratory

NASA Astrophysics Data System (ADS)

Shimaya, H.; Ishida, T.; Ishikawa, S.; Suda, S.; Tanuma, H.; Akamatsu, H.; Ohashi, H.; Ijima, N.; Inoue, M.; Ezoe, Y.; Ishisaki, Y.; Ohashi, T.; Shinozaki, K.; Mitsuda, K.; Liu, L.; Wang, J.

2013-09-01

We have observed the emission spectra in collisions of bare oxygen ions with a helium gas target in the soft x-ray region with a window-less silicon drift detector at the collision energy range of 48-80 keV. The dominant soft x-ray emission corresponds to the 1s-2p transition of hydrogen-like oxygen O7+ produced by the single-electron charge exchange reaction. Other emission lines are the 1s-3p, 1s-4p and 1s-5p transitions of O7+, and also the 1s2-1s2p transition of O6+ produced by the true double-electron capture. The cascades from the upper states result in a large population of the 2p state, even though the direct capture into the 2p state is extremely scarcer than those into the 3p, 4p and 5p states.

A comparison of empirical and experimental O7+, O8+, and O/H values, with applications to terrestrial solar wind charge exchange

NASA Astrophysics Data System (ADS)

Whittaker, Ian C.; Sembay, Steve

2016-07-01

Solar wind charge exchange occurs at Earth between the neutral planetary exosphere and highly charged ions of the solar wind. The main challenge in predicting the resultant photon flux in the X-ray energy bands is due to the interaction efficiency, known as the α value. This study produces experimental α values at the Earth, for oxygen emission in the range of 0.5-0.7 keV. Thirteen years of data from the Advanced Composition Explorer are examined, comparing O7+ and O8+ abundances, as well as O/H to other solar wind parameters allowing all parameters in the αO7,8+ calculation to be estimated based on solar wind velocity. Finally, a table is produced for a range of solar wind speeds giving average O7+ and O8+ abundances, O/H, and αO7,8+ values.

Jordan Reforms Public Education to Compete in a Global Economy

ERIC Educational Resources Information Center

Erickson, Paul W.

2009-01-01

The King of Jordan's vision for education is resulting in innovative projects for the country. King Abdullah II wants Jordan to develop its human resources through public education to equip the workforce with skills for the future. From King Abdullah II's vision, the Education Reform for a Knowledge Economy (ERfKE) project implemented by the…

Signatures of the electron saddle swaps mechanism in the photon spectra following charge-exchange collisions

NASA Astrophysics Data System (ADS)

Otranto, Sebastian

2014-10-01

During the last few years, several experimental and theoretical studies have focused on state selective charge exchange processes between charged ions and alkali metals. These data are of particular importance for the tokamak nuclear fusion reactor program, since diagnostics on the plasma usually rely on charge-exchange spectroscopy. In this sense, alkali metals, have been proposed as potential alternatives to excited hydrogen/deuterium for which laboratory experiments are not feasible at present. In this talk, we present our recent work involving ion collisions with alkali metals. Oscillatory structures in the angular differential charge-exchange cross sections obtained using the MOTRIMS technique are correctly described by classical trajectory Monte Carlo simulations. These oscillations are found to originate from the number of swaps the electron undergoes around the projectile-target potential saddle before capture takes place and are very prominent at impact energies below 10 keV/amu. Moreover, cross sections of higher order of differentiability also indicate that the swaps leave distinctive signatures in the (n,l)-state selective cross sections and in the photon line emission cross sections. Oscillatory structures for the x-ray hardness ratio parameter are also predicted. In collaboration with Ronnie Hoekstra, Zernike Institute for Advanced Materials, University of Groningen and Ronald Olson, Department of Physics, Missouri University of Science and Technology.

Solar wind charge exchange in laboratory - Observation of forbidden X-ray transitions

NASA Astrophysics Data System (ADS)

Numadate, Naoki; Shimaya, Hirofumi; Ishida, Takuya; Okada, Kunihiro; Nakamura, Nobuyuki; Tanuma, Hajime

2017-10-01

We have reproduced solar wind charge exchange collisions of hydrogen-like O7+ ions with He gas at collision energies of 42 keV in the laboratory and observed the forbidden transition of 1s21S0 -1s2s 3S1 in helium-like O6+ ions produced by single electron capture. The measured soft X-ray spectrum had a peak at 560 eV which corresponds to the energy of the forbidden 1s21S0 -1s2s 3S1 transition in the O6+ ion, and a reasonable energy difference between peak positions of the forbidden and resonance lines was found, which ensured that we succeeded in observing the forbidden transition of O6+ ions. The dominant electron capture level in the collision of O7+ ions with He can be estimated to be a principal quantum number n = 4 by the classical over barrier model and the two-center atomic orbital close coupling method. After the charge exchange, the population of the 1s2s state becomes large due to cascade transitions from the higher excited states, so the long-lived forbidden transition to the 1s21S0 ground state is one of main features observed in the charge exchange spectra.

Evidence of conformational exchange averaging in the thermal rotational spectrum of ethyl cyanoformate.

PubMed

True, Nancy S

2006-06-15

The Stark modulated low resolution microwave spectrum of ethyl cyanoformate between 21.5 and 24.0 GHz at 210, 300, and 358 K, which shows the J + 1 <-- J = 8 <-- 7 bands of three species, is compared to simulations based on electronic structure calculations at the MP2/6-311++G theory level. Calculations at this theory level reproduce the relative energies of the syn-anti and syn-gauche conformers, obtained in a previous study, and indicate that the barrier to conformer exchange is approximately 360 cm(-1) higher in energy than the syn-anti minimum. Simulated spectra of the eigenstates of the calculated O-ethyl torsional potential function reproduce the relative intensities and shapes of the lower and higher frequency bands which correspond to transitions of the syn-anti and syn-gauche conformers, respectively, but fail to reproduce the intense center band in the experimental spectra. A model incorporating exchange averaging reproduces the intensity of the center band and its temperature dependence. These simulations indicate that a large fraction of the thermal population at all three temperatures undergoes conformational exchange with an average energy specific rate constant, , of approximately 25 GHz. This model can explain anomalies present in rotational spectra of many other compounds composed of mixtures of conformers.

Safety evaluation -- Spent water treatment system components inventory release

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dodd, E.N. Jr.

1995-01-24

Over the past few years various impediments to shipment of generated spent basin water treatment system components have resulted in the accumulation of quantities of these waste items at 100K. Specifically, there are (as of 01/01/95) 13 grout/culvert packaged cartridge filters (CF), four unpackaged cartridge filters, 60 spent ion exchange columns (IXC) and seven ion exchange modules (IXM) at 100K awaiting shipment for final waste disposal. As a result of the accumulation of this waste, the question has arisen regarding the consequences of potential releases of the inventory of radionuclides in these waste items relative to the K Area safetymore » envelope. The purpose of this paper is to address this question. The initial step evaluating the consequences of potential release of material from the spent water treatment system components was to determine the individual and total radionuclide inventories of concern. Generally the radioisotopes of concern to the dose consequences were Sr/Y-90, Cs-137, and the transuranic (TRU) isotopes. The loading of these radioisotopes needed to be determined for each of the components of the total number of accumulated IXCs, IXMs and CFs. This evaluation examines four potential releases of material from the spent water treatment system components. These releases are: the release of material from all 39 IXCs stored in 183-KW; the release of material from the IXCs, IXMs and CFs at 105-KE and 105-KW; the release of material from the 13 CFs stored behind 105-KE; and the non-mechanistic release of the total stored waste inventory.« less

Isobaric analog states in rare-earth nuclei studied with the ( 3He, t) charge-exchange reaction at θL = 0°

NASA Astrophysics Data System (ADS)

Jänecke, J.; Aarts, E. H. L.; Drentje, A. G.; Harakeh, M. N.; Gaarde, C.

1983-02-01

The ( 3He, t) charge-exchange reaction leading to the ground-state isobaric analog states (IAS) of 152, 154, 156, 158, 160Gd, 160,162Dy, 162,164,166,168,170Er, 170, 172, 174, 176Yb and 176, 178, 180Hf has been studied at θL = 0° and E( 3He) = 60.5 MeV. The reaction 28Si( 3He, t) 28P was used for energy calibration. The centroid energies of most IAS were determined to ±6 keV. Coulomb displacement energies have been extracted from the measured Q-values. They display the influence of non-spherical nuclear shapes which increase the rms radii and lower the Coulomb displacement energies. The dependence on both quadrupole and hexadecapole deformations is apparent with deformation parameters in good agreement with results from other measurements. The total widths Γ of the IAS are in the range 30 to 110 keV. They increase more strongly with neutron excess than is known for the IAS of the Sn and Te isotopes. The width of the IAS of 176Yb is anomalously low. The zero-degree ( 3He, t) cross sections are in the range 5 to 20 μb/sr. They generally increase with neutron excess except for the sequence of Yb isotopes. No systematic dependence on ( N - Z) appears to exist. Excitation energies and zero-degree cross sections for the reactions 28Si( 3He, t) 28P, 16O( 3He,t) 16F and 12C( 3He,t) 12N are reported.

Revising the Local Bubble Model due to Solar Wind Charge Exchange X-ray Emission

NASA Astrophysics Data System (ADS)

Shelton, Robin L.

The hot Local Bubble surrounding the solar neighborhood has been primarily studied through observations of its soft X-ray emission. The measurements were obtained by attributing all of the observed local soft X-rays to the bubble. However, mounting evidence shows that the heliosphere also produces diffuse X-rays. The source is solar wind ions that have received an electron from another atom. The presence of this alternate explanation for locally produced diffuse X-rays calls into question the existence and character of the Local Bubble. This article addresses these questions. It reviews the literature on solar wind charge exchange (SWCX) X-ray production, finding that SWCX accounts for roughly half of the observed local 1/4 keV X-rays found at low latitudes. This article also makes predictions for the heliospheric O VI column density and intensity, finding them to be smaller than the observational error bars. Evidence for the continued belief that the Local Bubble contains hot gas includes the remaining local 1/4 keV intensity, the observed local O VI column density, and the need to fill the local region with some sort of plasma. If the true Local Bubble is half as bright as previously thought, then its electron density and thermal pressure are 1/sqrt{2} as great as previously thought, and its energy requirements and emission measure are 1/2 as great as previously thought. These adjustments can be accommodated easily, and, in fact, bring the Local Bubble's pressure more in line with that of the adjacent material. Suggestions for future work are made.

Revising the Local Bubble Model due to Solar Wind Charge Exchange X-ray Emission

NASA Astrophysics Data System (ADS)

Shelton, Robin L.

2009-03-01

The hot Local Bubble surrounding the solar neighborhood has been primarily studied through observations of its soft X-ray emission. The measurements were obtained by attributing all of the observed local soft X-rays to the bubble. However, mounting evidence shows that the heliosphere also produces diffuse X-rays. The source is solar wind ions that have received an electron from another atom. The presence of this alternate explanation for locally produced diffuse X-rays calls into question the existence and character of the Local Bubble. This article addresses these questions. It reviews the literature on solar wind charge exchange (SWCX) X-ray production, finding that SWCX accounts for roughly half of the observed local 1/4 keV X-rays found at low latitudes. This article also makes predictions for the heliospheric O VI column density and intensity, finding them to be smaller than the observational error bars. Evidence for the continued belief that the Local Bubble contains hot gas includes the remaining local 1/4 keV intensity, the observed local O VI column density, and the need to fill the local region with some sort of plasma. If the true Local Bubble is half as bright as previously thought, then its electron density and thermal pressure are 1/sqrt{2} as great as previously thought, and its energy requirements and emission measure are 1/2 as great as previously thought. These adjustments can be accommodated easily, and, in fact, bring the Local Bubble’s pressure more in line with that of the adjacent material. Suggestions for future work are made.

Energetic neutral atom imaging at low altitudes from the Swedish microsatellite Astrid: Images and spectral analysis

NASA Astrophysics Data System (ADS)

Brandt, Pontus C.:son; Barabash, Stas; Norberg, Olle; Lundin, Rickard; Roelof, Edmond C.; Chase, Christopher J.

1999-02-01

Observations of energetic neutral atoms (ENA) in the energy range 26-52 keV are reported from four occasions during geomagnetically disturbed periods. The data were acquired by the ENA imager flown on the Swedish microsatellite Astrid in a 1000 km circular orbit with 83° inclination. The ENA imager separates charged particles from neutrals through an electrostatic deflection system in the energy range between 0.1 and 114 keV. ENA images obtained from vantage points in the polar cap and in the afternoon magnetic local time (MLT) hours looking into the antisunward hemisphere show intense ENA fluxes (~104(cm2srs)-1 over 26-37 keV) coming from the dusk region and low altitudes (~300 km). The morphology shows no relation to local magnetic field excluding the possibility of charged particle detection. It is concluded that the source of these ENAs are precipitating/mirroring ions from the ring current/trapped radiation interacting with the exobase on auroral L-shells and in the dusk region. The observed ENA fluxes show a relation with Kp and Dst geomagnetic indices. The observed ENA spectrum from a geomagnetic storm on February 8, 1995, is investigated in more detail and compared to the parent ion spectrum obtained by the Defense Meteorological Satellite Project (DMSP) satellite, F12, during the same period on L=6+/-2 around dusk. The observed ENA spectral slope is used to derive the parent ion spectral temperature. The derived ion temperatures range is 3.0-6.0 keV for H and 4.5-8.5 keV for O. The higher of these ion temperatures comes closest in agreement to the extrapolated DMSP spectrum leading us to favor O over H as the species of the detected ENAs. It is shown that the detected ENAs must have been produced at L>=6 to reach the detector without atmospheric attenuation and that the main energy dependence of the ENA spectrum, apart from the parent ion spectrum, is governed by the energy dependence of the charge exchange cross section between ions and exospheric oxygen.

The Broadband Spectral Variability of Holmberg IX X-1

NASA Astrophysics Data System (ADS)

Walton, D. J.; Fürst, F.; Harrison, F. A.; Middleton, M. J.; Fabian, A. C.; Bachetti, M.; Barret, D.; Miller, J. M.; Ptak, A.; Rana, V.; Stern, D.; Tao, L.

2017-04-01

We present results from four new broadband X-ray observations of the extreme ultraluminous X-ray source Holmberg IX X-1 ({L}{{X}}> {10}40 erg s-1), performed by Suzaku and NuSTAR in coordination. Combined with the archival data, we now have broadband observations of this remarkable source from six separate epochs. Two of these new observations probe lower fluxes than seen previously, allowing us to extend our knowledge of the broadband spectral variability exhibited. The spectra are well fit by two thermal blackbody components that dominate the emission below 10 keV, as well as a steep ({{Γ }}˜ 3.5) power-law tail that dominates above ˜15 keV. Remarkably, while the 0.3-10.0 keV flux varies by a factor of ˜3 between all these epochs, the 15-40 keV flux varies by only ˜20%. Although the spectral variability is strongest in the ˜1-10 keV band, both of the thermal components are required to vary when all epochs are considered. We also revisit the search for iron absorption features by leveraging the high-energy NuSTAR data to improve our sensitivity to extreme velocity outflows in light of the ultra-fast outflow recently detected in NGC 1313 X-1. Iron absorption from a similar outflow along our line of sight can be ruled out in this case. We discuss these results in the context of super-Eddington accretion models that invoke a funnel-like geometry for the inner flow, and propose a scenario in which we have an almost face-on view of a funnel that expands to larger radii with increasing flux, resulting in an increasing degree of geometrical collimation for the emission from intermediate-temperature regions.

First direct determination of the 48Ca double-β decay Q value

NASA Astrophysics Data System (ADS)

Bustabad, S.; Bollen, G.; Brodeur, M.; Lincoln, D. L.; Novario, S. J.; Redshaw, M.; Ringle, R.; Schwarz, S.; Valverde, A. A.

2013-08-01

The low-energy beam and ion trap Penning trap mass spectrometer was used for an improved determination of the 48Ca double-β decay Q value: Qββ=4268.121(79)keV. The new value is 1.2 keV greater than the value in the 2012 atomic mass evaluation [Chin. Phys. CCPCHCQ1674-113710.1088/1674-1137/36/12/003 36, 1603 (2012)], a shift of three σ, and is a factor of 5 more precise. Accurate knowledge of this Q value is important for experimental searches to observe neutrinoless double-β decay (0νββ) in 48Ca and is essential for extracting the effective mass of the electron neutrino if the 48Ca half-life of 0νββ was experimentally determined.

Linking Home and School: The Home School Knowledge Exchange Project: Linking Home and School to Improve Children's Literacy

ERIC Educational Resources Information Center

Feiler, Anthony; Andrews, Jane; Greenhough, Pamela; Hughes, Martin; Johnson, David; Scanlan, Mary; Yee, Wan Ching

2008-01-01

The Government is urging teachers to engage more closely with families and is promoting the concept of the "extended" school. This article reports on the literacy strand of the Home School Knowledge Exchange (HSKE) project, directed by Professor Martin Hughes at the University of Bristol. A selection of literacy activities developed…

Knowledge Exchange between Universities and the Creative Industries in the UK: A Case Study of Current Practice

ERIC Educational Resources Information Center

Ferguson, Morag

2014-01-01

The importance to the economy of knowledge exchange between universities and industry has long been recognized, and in the UK a number of initiatives are in place to support such activities. These initiatives have helped to stimulate engagement between universities and the creative industries, a sector of increasing importance to the UK economy.…

Enhancing Knowledge Flow in a Health Care Context: A Mobile Computing Approach

PubMed Central

Souza, Diego Da Silva; de Lima, Patrícia Zudio; da Silveira, Pedro C; de Souza, Jano Moreira

2014-01-01

Background Advances in mobile computing and wireless communication have allowed people to interact and exchange knowledge almost anywhere. These technologies support Medicine 2.0, where the health knowledge flows among all involved people (eg, patients, caregivers, doctors, and patients’ relatives). Objective Our paper proposes a knowledge-sharing environment that takes advantage of mobile computing and contextual information to support knowledge sharing among participants within a health care community (ie, from patients to health professionals). This software environment enables knowledge exchange using peer-to-peer (P2P) mobile networks based on users’ profiles, and it facilitates face-to-face interactions among people with similar health interests, needs, or goals. Methods First, we reviewed and analyzed relevant scientific articles and software apps to determine the current state of knowledge flow within health care. Although no proposal was capable of addressing every aspect in the Medicine 2.0 paradigm, a list of requirements was compiled. Using this requirement list and our previous works, a knowledge-sharing environment was created integrating Mobile Exchange of Knowledge (MEK) and the Easy to Deploy Indoor Positioning System (EDIPS), and a twofold qualitative evaluation was performed. Second, we analyzed the efficiency and reliability of the knowledge that the integrated MEK-EDIPS tool provided to users according to their interest topics, and then performed a proof of concept with health professionals to determine the feasibility and usefulness of using this solution in a real-world scenario. Results . Using MEK, we reached 100% precision and 80% recall in the exchange of files within the peer-to-peer network. The mechanism that facilitated face-to-face interactions was evaluated by the difference between the location indicated by the EDIPS tool and the actual location of the people involved in the knowledge exchange. The average distance error was <6.28 m for an indoor environment. The usability and usefulness of this tool was assessed by questioning a sample of 18 health professionals: 94% (17/18) agreed the integrated MEK-EDIPS tool provides greater interaction among all the participants (eg, patients, caregivers, doctors, and patients’ relatives), most considered it extremely important in the health scenario, 72% (13/18) believed it could increase the knowledge flow in a health environment, and 67% (12/18) recommend it or would like to recommend its use. Conclusions The integrated MEK-EDIPS tool can provide more services than any other software tool analyzed in this paper. The proposed integrated MEK-EDIPS tool seems to be the best alternative for supporting health knowledge flow within the Medicine 2.0 paradigm. PMID:25427923

78 FR 13107 - Self-Regulatory Organizations; Miami International Securities Exchange LLC; Notice of Filing and...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-26

...'') \\5\\, NASDAQ OMX BX, Inc (``BX Options'') \\6\\, and BOX Options Exchange LLC (``BOX'') \\7\\ eliminated... (November 2, 2012) (SR-BX-2012-069). \\7\\ See Securities Exchange Act Release No. 68412 (December 12, 2012... competitive market comprised of eleven U.S. options exchanges in which sophisticated and knowledgeable market...

The Low‐Energy Neutral Imager (LENI)

PubMed Central

Mitchell, D. G.; Brandt, P. C.‐son.; Andrews, B. G.; Clark, G.

2016-01-01

Abstract To achieve breakthroughs in the areas of heliospheric and magnetospheric energetic neutral atom (ENA) imaging, a new class of instruments is required. We present a high angular resolution ENA imager concept aimed at the suprathermal plasma populations with energies between 0.5 and 20 keV. This instrument is intended for understanding the spatial and temporal structure of the heliospheric boundary recently revealed by Interstellar Boundary Explorer instrumentation and the Cassini Ion and Neutral Camera. The instrument is also well suited to characterize magnetospheric ENA emissions from low‐altitude ENA emissions produced by precipitation of magnetospheric ions into the terrestrial upper atmosphere, or from the magnetosheath where solar wind protons are neutralized by charge exchange, or from portions of the ring current region. We present a new technique utilizing ultrathin carbon foils, 2‐D collimation, and a novel electron optical design to produce high angular resolution (≤2°) and high‐sensitivity (≥10−3 cm2 sr/pixel) ENA imaging in the 0.5–20 keV energy range. PMID:27867800

XMM-Newton Observations of MBM 12: More Constraints on the Solar Wind Charge Exchange and Local Bubble Emissions

NASA Technical Reports Server (NTRS)

Koutroumpa, Dimitra; Smith, Randall K.; Edgar, Richard J.; Kuntz, Kip D.; Plucinsky, Paul P.; Snowden, Steven L.

2010-01-01

We present the first analysis of an XMM-Newton observation of the nearby molecular cloud MBM 12. We find that in the direction of MBM 12 the total O VII (0.57 keV) triplet emission is 1.8(+0.5/-0.6) photons/sq cm/s/sr (or Line Units - LU) while for the O VIII (0.65 keV) line emission we find a 3(sigma) upper limit of <1 LU. We also use a heliospheric model to calculate the O VII and O VIII emission generated by Solar Wind Charge-eXchange (SWCX) which we compare to the XMM-Newton observations. This comparison provides new constraints on the relative heliospheric and Local Bubble contributions to the local diffuse X-ray background. The heliospheric SWCX model predicts 0.82 LU for O VII, which accounts for approx. 46+/-15% of the observed value, and 0.33 LU for the O VIII line emission consistent with the XMM-Newton observed value. We discuss our results in combination with previous observations of the MBM 12 with CHANDRA and Suzaku.

3.55 keV line from exciting dark matter without a hidden sector

DOE PAGES

Berlin, Asher; DiFranzo, Anthony; Hooper, Dan

2015-04-24

In this study, models in which dark matter particles can scatter into a slightly heavier state which promptly decays to the lighter state and a photon (known as eXciting Dark Matter, or XDM) have been shown to be capable of generating the 3.55 keV line observed from galaxy clusters, while suppressing the flux of such a line from smaller halos, including dwarf galaxies. In most of the XDM models discussed in the literature, this up-scattering is mediated by a new light particle, and dark matter annihilations proceed into pairs of this same light state. In these models, the dark matter andmore » the mediator effectively reside within a hidden sector, without sizable couplings to the Standard Model. In this paper, we explore a model of XDM that does not include a hidden sector. Instead, the dark matter both up-scatters and annihilates through the near resonant exchange of an O(10 2) GeV pseudoscalar with large Yukawa couplings to the dark matter and smaller, but non-neglibile, couplings to Standard Model fermions. The dark matter and the mediator are each mixtures of Standard Model singlets and SU(2) W doublets. We identify parameter space in which this model can simultaneously generate the 3.55 keV line and the gamma-ray excess observed from the Galactic center, without conflicting with constraints from colliders, direct detection experiments, or observations of dwarf galaxies.« less

A screened independent atom model for the description of ion collisions from atomic and molecular clusters

NASA Astrophysics Data System (ADS)

Lüdde, Hans Jürgen; Horbatsch, Marko; Kirchner, Tom

2018-05-01

We apply a recently introduced model for an independent-atom-like calculation of ion-impact electron transfer and ionization cross sections to proton collisions from water, neon, and carbon clusters. The model is based on a geometrical interpretation of the cluster cross section as an effective area composed of overlapping circular disks that are representative of the atomic contributions. The latter are calculated using a time-dependent density-functional-theory-based single-particle description with accurate exchange-only ground-state potentials. We find that the net capture and ionization cross sections in p-X n collisions are proportional to n α with 2/3 ≤ α ≤ 1. For capture from water clusters at 100 keV impact energy α is close to one, which is substantially different from the value α = 2/3 predicted by a previous theoretical work based on the simplest-level electron nuclear dynamics method. For ionization at 100 keV and for capture at lower energies we find smaller α values than for capture at 100 keV. This can be understood by considering the magnitude of the atomic cross sections and the resulting overlaps of the circular disks that make up the cluster cross section in our model. Results for neon and carbon clusters confirm these trends. Simple parametrizations are found which fit the cross sections remarkably well and suggest that they depend on the relevant bond lengths.

Truly Incomplete and Complex Chromosomal Exchanges in Human Fibroblast Cells Exposed In Situ to Energetic Heavy Ions

NASA Technical Reports Server (NTRS)

Wu, Honglu; Durante, marco; Furusawa, Yoshiya; George, Kerry; Kawata, Tetsuya; Cucinotta, Francis A.

2003-01-01

Confluent human fibroblast cells (AG 1522) were irradiated with gamma rays, 490 MeV/nucleon Si, or with Fe ions at either 200 or 500 MeV/nucleon. The cells were allowed to repair at 37 C for 24 hours after exposure, and a chemically induced premature chromosome condensation (PCC) technique was used to condense chromosomes in the G2 phase of the cell cycle. Incomplete and complex exchanges were analyzed in the irradiated samples. In order to verify that chromosomal breaks were truly unrejoined, chromosome aberrations were analyzed using a combination of whole chromosome specific probes and probes specific for the telomere region of the chromosome. Results showed that the frequency of unrejoined chromosome breaks was higher after high-LET radiation, and consequently, the ratio of incomplete to complete exchanges increased steadily with LET up to 440 keV/micron, the highest LET value in the present study. For samples exposed to 200 MeV/nucleon Fe ions, chromosome aberrations were analyzed using the multicolor FISH (mFISH) technique that allow identification of both complex and truly incomplete exchanges. Results of the mFISH study showed that 0.7 and 3 Gy dose of the Fe ions produced similar ratios of complex to simple exchanges and incomplete to complete exchanges, values for which were higher than those obtained after a 6 Gy gamma exposure. After 0.7 Gy of Fe ions, most complex aberrations were found to involve three or four chromosomes, which is a likely indication of the maximum number of chromosome domains traversed by a single Fe ion track.

Growing School Networks for Instructional Improvement in Jordan, 2009-2010. CPRE Research Report, # RR-70

ERIC Educational Resources Information Center

Robinson, Marian A.

2011-01-01

In the last decade, the Hashemite Kingdom of Jordan has made a substantial commitment to improving the quality of its public education system. The main vehicle for this work has been the Education Reform for Knowledge Economy (ERfKE) initiative. To date, key investments have been made in early childhood education, school infrastructure,…

The characteristic pitch angle distributions of 1 eV to 600 keV protons near the equator based on Van Allen Probes observations

NASA Astrophysics Data System (ADS)

Yue, C.; Bortnik, J.; Thorne, R. M.; Ma, Q.; An, X.; Chappell, C. R.; Gerrard, A. J.; Lanzerotti, L. J.; Shi, Q.

2017-12-01

Understanding the source and loss processes of various plasma populations is greatly aided by having accurate knowledge of their pitch angle distributions (PADs). Here, we statistically analyze 1 eV to 600 keV hydrogen (H+) PADs near the geomagnetic equator in the inner magnetosphere based on Van Allen Probes measurements, to comprehensively investigate how the H+ PADs vary with different energies, magnetic local times (MLTs), L-shells, and geomagnetic conditions. Our survey clearly indicates four distinct populations with different PADs: (1) a pancake distribution of the plasmaspheric H+ at low L-shells except for dawn sector; (2) a bi-directional field-aligned distribution of the warm plasma cloak; (3) pancake or isotropic distributions of ring current H+; (4) radiation belt particles show pancake, butterfly and isotropic distributions depending on their energy, MLT and L-shell. Meanwhile, the pancake distribution of ring current H+ moves to lower energies as L-shell increases which is primarily caused by adiabatic transport. Furthermore, energetic H+ (> 10 keV) PADs become more isotropic following the substorm injections, indicating wave-particle interactions. The radiation belt H+ butterfly distributions are identified in a narrow energy range of 100 < E < 400 keV at large L (L > 5), which are less significant during quiet times and extend from dusk to dawn sector through midnight during substorms. The different PADs near the equator provide clues of the underlying physical processes that produce the dynamics of these different populations.

Importance of Doppler broadening in Compton scatter imaging techniques

NASA Astrophysics Data System (ADS)

Rao, Donepudi V.; Takeda, Tohoru; Itai, Yuji; Seltzer, S. M.; Hubbell, John H.; Zeniya, Tsutomu; Akatsuka, Takao; Cesareo, Roberto; Brunetti, Antonio; Gigante, Giovanni E.

2001-12-01

Compton scattering is a potential tool for the determination of bone mineral content or tissue density for dose planning purposes, and requires knowledge of the energy distribution of the X-rays through biological materials of medical interest in the X-ray and (gamma) -ray region. The energy distribution is utilized in a number of ways in diagnostic radiology, for example, in determining primary photon spectra, electron densities in separate volumes, and in tomography and imaging. The choice of the X-ray energy is more related to X-ray absorption, where as that of the scattering angle is more related to geometry. The evaluation of all the contributions are mandatory in Compton profile measurements and is important in X-ray imaging systems in order to achieve good results. In view of this, Compton profile cross-sections for few biological materials are estimated at nineteen K(alpha) X-ray energies and 60 keV (Am-241) photons. Energy broadening, geometrical broadening from 1 to 180 degree(s), FWHM of J(Pz) and FWHM of Compton energy broadening has been evaluated at various incident photon energies. These values are estimated around the centroid of the Compton profile with an energy interval of 0.1 keV and 1.0 keV for 60 keV photons. The interaction cross sections for the above materials are estimated using fractions-by-weight of the constituent elements. Input data for these tables are purely theoretical.

Lost in Knowledge Translation: Time for a Map?

ERIC Educational Resources Information Center

Graham, Ian D.; Logan, Jo; Harrison, Margaret B.; Straus, Sharon E.; Tetroe, Jacqueline; Caswell, Wenda; Robinson, Nicole

2006-01-01

There is confusion and misunderstanding about the concepts of knowledge translation, knowledge transfer, knowledge exchange, research utilization, implementation, diffusion, and dissemination. We review the terms and definitions used to describe the concept of moving knowledge into action. We also offer a conceptual framework for thinking about…

New Energetic Particle Data and Products from the GOES Program

NASA Astrophysics Data System (ADS)

Onsager, Terrance; Rodriguez, Juan

The NOAA Geostationary Operational Environmental Satellite (GOES) program has provided continuous, real-time measurements of the near-Earth space environment for decades. In addition to their scientific value, the GOES energetic particle measurements are the basis for a variety of space weather products and services, including the forecasting of elevated energetic particle levels, real-time knowledge of the satellite environment at geostationary orbit, and data to allow post-event analyses when satellite anomalies occur. The GOES satellites have traditionally provided measurements of high-energy electrons, protons, and alpha particles (100s of keV to 100s of MeV). Beginning with the launch of GOES-13 in 2006, the measurement capabilities were expanded to include medium-energy electrons and protons (10s to 100s of keV) with pitch angle resolution. The next generation of GOES satellites, starting with GOES-R in 2016, will include low-energy electrons and ions (10s of eV to 10s of keV) as well as energetic heavy ions. In this presentation, we will overview the GOES particle measurements available now and in the future and describe the space weather services and scientific investigations that these data support.

Determinants of Participating in Australian University Student Exchange Programs

ERIC Educational Resources Information Center

Daly, Amanda

2011-01-01

Outbound mobility programs such as exchange programs are one of the many strategies implemented at universities to develop graduates' intercultural skills and international knowledge. Few Australian students participate in exchange programs. This article presents a literature review and proposes a model of the contextual and individual factors…

Development of beamline U3A for AXAF synchrotron reflectivity calibrations

NASA Astrophysics Data System (ADS)

Burek, Anthony J.; Cobuzzi, J. C.; Fitch, Jonathan J.; Graessle, Dale E.; Ingram, R. H.; Sweeney, J. B.; Blake, Richard L.; Francoeur, R.; Sullivan, E. S.

1998-11-01

We discuss the development of beamline U3A at NSLS for AXAF telescope witness mirror reflectivity calibrations in the 1- 2 keV energy range. The beamline was originally constructed as a white light beamline and has been upgraded with the addition of a monochromator to meet the needs of the AXAF calibration program. The beamline consists of an upstream horizontally focussing gold coated elliptical mirror, a differential pumping section, a sample/filter chamber, a monochromator and a downstream filter set. The mirror is set at a 2 degree incident angle for a nominal high energy cutoff at 2 keV. The monochromator is a separated element, scanning, double crystal/multilayer design having low to moderate energy resolution. A fixed exit beam is maintained through the 7-70 degree Bragg angle range by longitudinal translation of the second scanning crystal. Tracking is achieved by computer control of the scan motors with lookup table positioning of the crystal rotary tables. All motors are in vacuum and there are no motional feedthroughs. Several different multilayer or crystal pairs are co-mounted on the monochromator crystal holders and can be exchanged in situ. Currently installed are a W/Si multilayer pair, beryl, and Na-(beta) alumina allowing energy coverage from 180 eV to 2000 eV. Measurements with Na-(beta) alumina and beryl show that beam impurity less than 0.1 percent can be achieved in the 1-2 keV energy range. Measured resolving powers are E/(Delta) E equals 60 for W/Si, 500-800 for (beta) alumina and 1500 to 3000 for beryl. Initial results suggest that signal to noise and beam purity are adequate in the 1-2 keV region to achieve the 1 percent calibration accuracy required by AXAF. This allows overlap of Ir MV edge data taken on x-ray beamline X8A and with low energy data taken on ALS beamline 6.3.2.

Electron beam accelerators—trends in radiation processing technology for industrial and environmental applications in Latin America and the Caribbean

NASA Astrophysics Data System (ADS)

Parejo Calvo, Wilson A.; Duarte, Celina L.; Machado, Luci Diva B.; Manzoli, Jose E.; Geraldo, Aurea Beatriz C.; Kodama, Yasko; Silva, Leonardo Gondim A.; Pino, Eddy S.; Somessari, Elizabeth S. R.; Silveira, Carlos G.; Rela, Paulo R.

2012-08-01

The radiation processing technology for industrial and environmental applications has been developed and used worldwide. In Latin America and the Caribbean and particularly in Brazil there are 24 and 16 industrial electron beam accelerators (EBA) respectively with energy from 200 keV to 10 MeV, operating in private companies and governmental institutions to enhance the physical and chemical properties of materials. However, there are more than 1500 high-current electron beam accelerators in commercial use throughout the world. The major needs and end-use markets for these electron beam (EB) units are R and D, wire and electric cables, heat shrinkable tubes and films, PE foams, tires, components, semiconductors and multilayer packaging films. Nowadays, the emerging opportunities in Latin America and the Caribbean are paints, adhesives and coatings cure in order to eliminate VOCs and for less energy use than thermal process; disinfestations of seeds; and films and multilayer packaging irradiation. For low-energy EBA (from 150 keV to 300 keV). For mid-energy EBA (from 300 keV to 5 MeV), they are flue gas treatment (SO2 and NOX removal); composite and nanocomposite materials; biodegradable composites based on biorenewable resources; human tissue sterilization; carbon and silicon carbide fibers irradiation; irradiated grafting ion-exchange membranes for fuel cells application; electrocatalysts nanoparticles production; and natural polymers irradiation and biodegradable blends production. For high-energy EBA (from 5 MeV to 10 MeV), they are sterilization of medical, pharmaceutical and biological products; gemstone enhancement; treatment of industrial and domestic effluents and sludge; preservation and disinfestations of foods and agricultural products; soil disinfestations; lignocellulosic material irradiation as a pretreatment to produce ethanol biofuel; decontamination of pesticide packing; solid residues remediation; organic compounds removal from wastewater; and treatment of effluent from petroleum production units and liquid irradiation process to treat vessel water ballast. On the other hand, there is a growing need of mobile EB facilities for different applications in South America.

Charge Exchange Contribution to the Decay of the Ring Current, Measured by Energetic Neutral Atoms (ENAs)

NASA Technical Reports Server (NTRS)

Jorgensen, A. M.; Henderson, M. G.; Roelof, E. C.; Reeves, G. D.; Spence, H. E.

2001-01-01

In this paper we calculate the contribution of charge exchange to the decay of the ring current. Past works have suggested that charge exchange of ring current protons is primarily responsible for the decay of the ring current during the late recovery phase, but there is still much debate about the fast decay of the early recovery phase. We use energetic neutral atom (ENA) measurements from Polar to calculate the total ENA energy escape. To get the total ENA escape we apply a forward modeling technique, and to estimate the total ring current energy escape we use the Dessler-Parker-Sckopke relationship. We find that during the late recovery phase of the March 10, 1998 storm ENAs with energies greater than 17.5 keV can account for 75% of the estimated energy loss from the ring current. During the fast recovery the measured ENAs can only account for a small portion of the total energy loss. We also find that the lifetime of the trapped ions is significantly shorter during the fast recovery phase than during the late recovery phase, suggesting that different processes are operating during the two phases.

Universities, SMEs and Social Capital: Can You Get Too Much of a Good Thing? An Illustrative Analysis of One University's Knowledge Exchange Programme

ERIC Educational Resources Information Center

Gordon, Ian

2016-01-01

This article explores a university knowledge exchange programme for small and medium-sized enterprise (SME) owner-managers. Specifically, it considers why a programme designed to achieve growth in a group of SMEs through the creation of a network high in social capital may have become a constraint on the programme's effectiveness over a period of…

Imaging Plasma Density Structures in the Soft X-Rays Generated by Solar Wind Charge Exchange with Neutrals

NASA Astrophysics Data System (ADS)

Sibeck, David G.; Allen, R.; Aryan, H.; Bodewits, D.; Brandt, P.; Branduardi-Raymont, G.; Brown, G.; Carter, J. A.; Collado-Vega, Y. M.; Collier, M. R.; Connor, H. K.; Cravens, T. E.; Ezoe, Y.; Fok, M.-C.; Galeazzi, M.; Gutynska, O.; Holmström, M.; Hsieh, S.-Y.; Ishikawa, K.; Koutroumpa, D.; Kuntz, K. D.; Leutenegger, M.; Miyoshi, Y.; Porter, F. S.; Purucker, M. E.; Read, A. M.; Raeder, J.; Robertson, I. P.; Samsonov, A. A.; Sembay, S.; Snowden, S. L.; Thomas, N. E.; von Steiger, R.; Walsh, B. M.; Wing, S.

2018-06-01

Both heliophysics and planetary physics seek to understand the complex nature of the solar wind's interaction with solar system obstacles like Earth's magnetosphere, the ionospheres of Venus and Mars, and comets. Studies with this objective are frequently conducted with the help of single or multipoint in situ electromagnetic field and particle observations, guided by the predictions of both local and global numerical simulations, and placed in context by observations from far and extreme ultraviolet (FUV, EUV), hard X-ray, and energetic neutral atom imagers (ENA). Each proposed interaction mechanism (e.g., steady or transient magnetic reconnection, local or global magnetic reconnection, ion pick-up, or the Kelvin-Helmholtz instability) generates diagnostic plasma density structures. The significance of each mechanism to the overall interaction (as measured in terms of atmospheric/ionospheric loss at comets, Venus, and Mars or global magnetospheric/ionospheric convection at Earth) remains to be determined but can be evaluated on the basis of how often the density signatures that it generates are observed as a function of solar wind conditions. This paper reviews efforts to image the diagnostic plasma density structures in the soft (low energy, 0.1-2.0 keV) X-rays produced when high charge state solar wind ions exchange electrons with the exospheric neutrals surrounding solar system obstacles. The introduction notes that theory, local, and global simulations predict the characteristics of plasma boundaries such the bow shock and magnetopause (including location, density gradient, and motion) and regions such as the magnetosheath (including density and width) as a function of location, solar wind conditions, and the particular mechanism operating. In situ measurements confirm the existence of time- and spatial-dependent plasma density structures like the bow shock, magnetosheath, and magnetopause/ionopause at Venus, Mars, comets, and the Earth. However, in situ measurements rarely suffice to determine the global extent of these density structures or their global variation as a function of solar wind conditions, except in the form of empirical studies based on observations from many different times and solar wind conditions. Remote sensing observations provide global information about auroral ovals (FUV and hard X-ray), the terrestrial plasmasphere (EUV), and the terrestrial ring current (ENA). ENA instruments with low energy thresholds (˜1 keV) have recently been used to obtain important information concerning the magnetosheaths of Venus, Mars, and the Earth. Recent technological developments make these magnetosheaths valuable potential targets for high-cadence wide-field-of-view soft X-ray imagers. Section 2 describes proposed dayside interaction mechanisms, including reconnection, the Kelvin-Helmholtz instability, and other processes in greater detail with an emphasis on the plasma density structures that they generate. It focuses upon the questions that remain as yet unanswered, such as the significance of each proposed interaction mode, which can be determined from its occurrence pattern as a function of location and solar wind conditions. Section 3 outlines the physics underlying the charge exchange generation of soft X-rays. Section 4 lists the background sources (helium focusing cone, planetary, and cosmic) of soft X-rays from which the charge exchange emissions generated by solar wind exchange must be distinguished. With the help of simulations employing state-of-the-art magnetohydrodynamic models for the solar wind-magnetosphere interaction, models for Earth's exosphere, and knowledge concerning these background emissions, Sect. 5 demonstrates that boundaries and regions such as the bow shock, magnetosheath, magnetopause, and cusps can readily be identified in images of charge exchange emissions. Section 6 reviews observations by (generally narrow) field of view (FOV) astrophysical telescopes that confirm the presence of these emissions at the intensities predicted by the simulations. Section 7 describes the design of a notional wide FOV "lobster-eye" telescope capable of imaging the global interactions and shows how it might be used to extract information concerning the global interaction of the solar wind with solar system obstacles. The conclusion outlines prospects for missions employing such wide FOV imagers.

Vacuum system design and tritium inventory for the charge exchange diagnostic on the Tokamak Fusion Test Reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Medley, S.S.

The application of charge exchange analyzers for the measurement of ion temperature in fusion plasma experiments requires a direct connection between the diagnostic and plasma-discharge vacuum chambers. Differential pumping of the gas load from the diagnostic stripping cell operated at > or approx. = 10/sup -3/ Torr is required to maintain the analyzer chamber at a pressure of < or approx. = 10/sup -6/ Torr. The migration of gases between the diagnostic and plasma vacuum chambers must be minimized. In particular, introduction of the analyzer stripping cell gas into the plasma chamber having a base pressure of < or approx.more » = 10/sup -8/ Torr must be suppressed. The charge exchange diagnostic for the Tokamak Fusion Test Reactor (TFTR) is comprised of two analyzer systems designed to contain a total of 18 independent mass/energy analyzers and one diagnostic neutral beam rated at 80 keV, 15 A. The associated arrays of multiple, interconnected vacuum systems were analyzed using the Vacuum System Transient Simulator (Vsts) computer program which models the transient transport of multigas species through complex networks of ducts, valves, traps, vacuum pumps, and other related vacuum system components. In addition to providing improved design performance at reduced costs, the analysis yields estimates for the exchange of tritium from the torus to the diagnostic components and of the diagnostic working gases to the torus.« less

Chromosomal intrachanges induced by swift iron ions

NASA Astrophysics Data System (ADS)

Horstmann, M.; Durante, M.; Johannes, C.; Obe, G.

We measured the induction of aberrations in human chromosome 5 by iron ions using the novel technique of multicolor banding in situ hybridization (mBAND). Human lymphocytes isolated from whole blood were exposed in vitro to 500 MeV/n (LET=200 keV/μ m, doses 1 or 4 Gy) 56Fe nuclei at the HIMAC accelerator in Chiba (Japan). Chromosomes were prematurely condensed by calyculin A after 48 h in culture, and slides were painted by mBAND (MetaSystems). We found a frequency of 0.11 and 0.57 residual breakpoints per chromosome 5 after 1 Gy and 4 Gy Fe-ions, respectively. The distribution per unit length were similar in the p- and q-arm of chromosome 5, and >50% of the observed fragments measured <30% of the whole chromosome length. Only small fragments (<40% of the chromosome size) were involved in intra-chromosomal exchanges (interstitial deletions or inversions), whereas fragments up to 75% of the whole chromosome 5 were found in inter-chromosomal exchanges. We measured more inter-changes than intra-changes, and more intra-arm than inter-arm exchanges at both doses. No significant differences in the ratios of these aberrations were detected with respect to X-rays. On the other hand, Fe-ions induced a significantly higher fraction of complex-type exchanges when compared to sparsely ionizing radiation. Work supported by DLR, BMBF, INTAS and NIRS-HIMAC.

Observations of solar wind ion charge exchange in the comet Halley coma

NASA Technical Reports Server (NTRS)

Fuselier, S. A.; Shelley, E. G.; Goldstein, B. E.; Goldstein, R.; Neugebauer, M.; Ip, W.-H.; Balsiger, H.; Reme, H.

1991-01-01

Giotto Ion Mass Spectrometer/High Energy Range Spectrometer (IMS/HERS) observations of solar wind ions show charge exchange effects and solar wind compositional changes in the coma of comet Halley. As the comet was approached, the He(++) to proton density ratio increased until about 1 hour before closest approach after which time it decreased. Abrupt increases in this ratio were also observed in the beginning and near the end of the so-called Mystery Region (8.6 - 5.5(10)(exp 5) km from the comet along the spacecraft trajectory). These abrupt increases in the density ratio were well correlated with enhanced fluxes of keV electrons as measured by the Giotto plasma electron spectrometer. The general increase and then decrease of the He(++) to proton density ratio is quantitatively consistent with a combination of the addition of protons of cometary origin to the plasma and loss of plasma through charge exchange of protons and He(++). In general agreement with the solar wind proton and He(++) observations, solar wind oxygen and carbon ions were observed to charge exchange from higher to lower charge states with decreasing distance to the comet. The more abrupt increases in the He(++) to proton and the He(++) to O(6+) density ratios in the mystery region require a change in the solar wind ion composition in this region while the correlation with energetic electrons indicates processes associated with the comet.

SU-C-201-03: Coded Aperture Gamma-Ray Imaging Using Pixelated Semiconductor Detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joshi, S; Kaye, W; Jaworski, J

2015-06-15

Purpose: Improved localization of gamma-ray emissions from radiotracers is essential to the progress of nuclear medicine. Polaris is a portable, room-temperature operated gamma-ray imaging spectrometer composed of two 3×3 arrays of thick CdZnTe (CZT) detectors, which detect gammas between 30keV and 3MeV with energy resolution of <1% FWHM at 662keV. Compton imaging is used to map out source distributions in 4-pi space; however, is only effective above 300keV where Compton scatter is dominant. This work extends imaging to photoelectric energies (<300keV) using coded aperture imaging (CAI), which is essential for localization of Tc-99m (140keV). Methods: CAI, similar to the pinholemore » camera, relies on an attenuating mask, with open/closed elements, placed between the source and position-sensitive detectors. Partial attenuation of the source results in a “shadow” or count distribution that closely matches a portion of the mask pattern. Ideally, each source direction corresponds to a unique count distribution. Using backprojection reconstruction, the source direction is determined within the field of view. The knowledge of 3D position of interaction results in improved image quality. Results: Using a single array of detectors, a coded aperture mask, and multiple Co-57 (122keV) point sources, image reconstruction is performed in real-time, on an event-by-event basis, resulting in images with an angular resolution of ∼6 degrees. Although material nonuniformities contribute to image degradation, the superposition of images from individual detectors results in improved SNR. CAI was integrated with Compton imaging for a seamless transition between energy regimes. Conclusion: For the first time, CAI has been applied to thick, 3D position sensitive CZT detectors. Real-time, combined CAI and Compton imaging is performed using two 3×3 detector arrays, resulting in a source distribution in space. This system has been commercialized by H3D, Inc. and is being acquired for various applications worldwide, including proton therapy imaging R&D.« less

Preparedness of Americans for the Affordable Care Act.

PubMed

Barcellos, Silvia Helena; Wuppermann, Amelie C; Carman, Katherine Grace; Bauhoff, Sebastian; McFadden, Daniel L; Kapteyn, Arie; Winter, Joachim K; Goldman, Dana

2014-04-15

This paper investigates whether individuals are sufficiently informed to make reasonable choices in the health insurance exchanges established by the Affordable Care Act (ACA). We document knowledge of health reform, health insurance literacy, and expected changes in healthcare using a nationally representative survey of the US population in the 5 wk before the introduction of the exchanges, with special attention to subgroups most likely to be affected by the ACA. Results suggest that a substantial share of the population is unprepared to navigate the new exchanges. One-half of the respondents did not know about the exchanges, and 42% could not correctly describe a deductible. Those earning 100-250% of federal poverty level (FPL) correctly answered, on average, 4 out of 11 questions about health reform and 4.6 out of 7 questions about health insurance. This compares with 6.1 and 5.9 correct answers, respectively, for those in the top income category (400% of FPL or more). Even after controlling for potential confounders, a low-income person is 31% less likely to score above the median on ACA knowledge questions, and 54% less likely to score above the median on health insurance knowledge than a person in the top income category. Uninsured respondents scored lower on health insurance knowledge, but their knowledge of ACA is similar to the overall population. We propose that simplified options, decision aids, and health insurance product design to address the limited understanding of health insurance contracts will be crucial for ACA's success.

Nurses' participation in personal knowledge transfer: the role of leader-member exchange (LMX) and structural empowerment.

PubMed

Davies, Alicia; Wong, Carol A; Laschinger, Heather

2011-07-01

The purpose of this study was to test Kanter's theory by examining relationships among structural empowerment, leader-member exchange (LMX) quality and nurses' participation in personal knowledge transfer activities. Despite the current emphasis on evidence-based practice in health care, research suggests that implementation of research findings in everyday clinical practice is unsystematic at best with mixed outcomes. This study was a secondary analysis of data collected using a non-experimental, predictive mailed survey design. A random sample of 400 registered nurses who worked in urban tertiary care hospitals in Ontario yielded a final sample of 234 for a 58.5% response rate. Hierarchical multiple linear regression analysis revealed that the combination of LMX and structural empowerment accounted for 9.1% of the variance in personal knowledge transfer but only total empowerment was a significant independent predictor of knowledge transfer (β=0.291, t=4.012, P<0.001). Consistent with Kanter's Theory, higher levels of empowerment and leader-member exchange quality resulted in increased participation in personal knowledge transfer in practice. The results reinforce the pivotal role of nurse managers in supporting empowering work environments that are conducive to transfer of knowledge in practice to provide evidence-based care. © 2011 The Authors. Journal compilation © 2011 Blackwell Publishing Ltd.

Evaluating an Indigenous health curriculum for diabetes prevention: engaging the community through talking circles and knowledge translation of results.

PubMed

Khayyat Kholghi, Maedeh; Bartlett, Gillian; Phillips, Morgan; Salsberg, Jon; McComber, Alex M; Macaulay, Ann C

2018-01-16

Kahnawà:ke is a Kanien'kehá:ka (Mohawk) community in Quebec, Canada. In 1997, the community-controlled Kateri Memorial Hospital Centre in partnership with the Kahnawake Education Center, and the Kahnawake Schools Diabetes Prevention Project (KSDPP) developed an elementary school diabetes prevention health education program, aimed to increase knowledge of Type 2 diabetes, healthy eating and active lifestyles. Long-term goals for KSDPP community and school interventions are to decrease obesity and diabetes. To evaluate the Kateri Memorial Hospital Centre Health Education Program for Diabetes Prevention (HEP) and use key principles of knowledge translation to promote understanding of results to upgrade HEP content and improve delivery. A KSDPP community-based participatory research team used mixed methods for evaluation, combining a cross-sectional survey for 23 teachers with interviews of two elementary school principals and three culturally appropriate Indigenous talking circles with HEP authors, teachers and parents. Questionnaire results were presented as descriptive statistics. The thematic textual analysis identified emerging themes from talking circles and interviews. Facilitators of HEP delivery were an acknowledgement of its importance; appreciation of prepared lesson plans for teachers; and KSDPP's strong community presence. Barriers included reduced administrative support and instructional time due to competing academic demands; the need for increased Kanien'kehá:ka cultural content; and outdated resource materials. Recommendations included increasing teacher training, Kanien'kehá:ka cultural content and administrative support. Community researchers undertook detailed knowledge translation activities of facilitators, barriers and recommendations with hospital and education centre administrators and Kahnawà:ke community to maximize uptake of findings before external dissemination of results. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Knowledge transfer and exchange processes for environmental health issues in Canadian Aboriginal communities.

PubMed

Jack, Susan M; Brooks, Sandy; Furgal, Chris M; Dobbins, Maureen

2010-02-01

Within Canadian Aboriginal communities, the process for utilizing environmental health research evidence in the development of policies and programs is not well understood. This fundamental qualitative descriptive study explored the perceptions of 28 environmental health researchers, senior external decision-makers and decision-makers working within Aboriginal communities about factors influencing knowledge transfer and exchange, beliefs about research evidence and Traditional Knowledge and the preferred communication channels for disseminating and receiving evidence. The results indicate that collaborative relationships between researchers and decision-makers, initiated early and maintained throughout a research project, promote both the efficient conduct of a study and increase the likelihood of knowledge transfer and exchange. Participants identified that empirical research findings and Traditional Knowledge are different and distinct types of evidence that should be equally valued and used where possible to provide a holistic understanding of environmental issues and support decisions in Aboriginal communities. To facilitate the dissemination of research findings within Aboriginal communities, participants described the elements required for successfully crafting key messages, locating and using credible messengers to deliver the messages, strategies for using cultural brokers and identifying the communication channels commonly used to disseminate and receive this type of information.

Knowledge Transfer and Exchange Processes for Environmental Health Issues in Canadian Aboriginal Communities

PubMed Central

Jack, Susan M.; Brooks, Sandy; Furgal, Chris M.; Dobbins, Maureen

2010-01-01

Within Canadian Aboriginal communities, the process for utilizing environmental health research evidence in the development of policies and programs is not well understood. This fundamental qualitative descriptive study explored the perceptions of 28 environmental health researchers, senior external decision-makers and decision-makers working within Aboriginal communities about factors influencing knowledge transfer and exchange, beliefs about research evidence and Traditional Knowledge and the preferred communication channels for disseminating and receiving evidence. The results indicate that collaborative relationships between researchers and decision-makers, initiated early and maintained throughout a research project, promote both the efficient conduct of a study and increase the likelihood of knowledge transfer and exchange. Participants identified that empirical research findings and Traditional Knowledge are different and distinct types of evidence that should be equally valued and used where possible to provide a holistic understanding of environmental issues and support decisions in Aboriginal communities. To facilitate the dissemination of research findings within Aboriginal communities, participants described the elements required for successfully crafting key messages, locating and using credible messengers to deliver the messages, strategies for using cultural brokers and identifying the communication channels commonly used to disseminate and receive this type of information. PMID:20616996

Plasma Inter-Particle and Particle-Wall Interactions

NASA Astrophysics Data System (ADS)

Patino, Marlene Idy

An improved understanding of plasma inter-particle and particle-wall interactions is critical to the advancement of plasma devices used for space electric propulsion, fusion, high-power communications, and next-generation energy systems. Two interactions of particular importance are (1) ion-atom collisions in the plasma bulk and (2) secondary electron emission from plasma-facing materials. For ion-atom collisions, interactions between fast ions and slow atoms are commonly dominated by charge-exchange and momentum-exchange collisions that are important to understanding the performance and behavior of many plasma devices. To investigate this behavior, this work developed a simple, well-characterized experiment that accurately measures the effects of high energy xenon ions incident on a background of xenon neutral atoms. By comparing these results to both analytical and computational models of ion-atom interactions, we discovered the importance of (1) accurately treating the differential cross-sections for momentum-exchange and charge-exchange collisions over all neutral background pressures, and (2) commonly overlooked interactions, including ion-induced electron emission and neutral-neutral ionization collisions, at high pressures. Data provide vital information on the angular scattering distributions of charge-exchange and momentum-exchange ions at 1.5 keV relevant for ion thrusters, and serve as canonical data for validation of plasma models. This work also investigates electron-induced secondary electron emission behavior relevant to materials commonly considered for plasma thrusters, fusion systems, and many other plasma devices. For such applications, secondary electron emission can alter the sheath potential, which can significantly affect device performance and life. Secondary electron emission properties were measured for materials that are critical to the efficient operation of many plasma devices, including: graphite (for tokamaks, ion thrusters, and traveling wave tubes), lithium (for tokamak walls), tungsten (the most promising material for future tokamaks such as ITER), and nickel (for plasma-enhanced chemistry). Measurements were made for incident electron energies up to 1.5 keV and angles between 0 and 78°. The most significant results from these measurements are as follows: (1) first-ever measurements of naturally-forming tungsten fuzz show a more than 40% reduction in secondary electron emission and an independence on incidence angle; (2) original measurements of lithium oxide show a 2x and 6x increase in secondary electron emission for 17% and 100% oxidation; and (3) unique measurements of Ni(110) single crystal show extrema in secondary electron emission when incidence angle is varied and an up to 36% increase at 0° over polycrystalline nickel. Each of these results are important discoveries for improving plasma devices. For example, from (1), the growth of tungsten fuzz in tokamaks is desirable for minimizing adverse secondary electron emission effects. From (2), the opposite is true for tokamaks with lithium coatings which are oxidized by typical residual gases. From (3), secondary electron emission from Ni(110) catalysts in plasma-enhanced chemistry may facilitate further reactions.

78 FR 48518 - Self-Regulatory Organizations; NASDAQ OMX BX, Inc.; Notice of Filing and Immediate Effectiveness...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-08

... Organizations; NASDAQ OMX BX, Inc.; Notice of Filing and Immediate Effectiveness of a Proposed Rule Change To..., NASDAQ OMX BX, Inc. (``BX'' or ``Exchange'') filed with the Securities and Exchange Commission... market comprised of eleven U.S. options exchanges in which sophisticated and knowledgeable market...

Truly incomplete and complex exchanges in prematurely condensed chromosomes of human fibroblasts exposed in vitro to energetic heavy ions

NASA Technical Reports Server (NTRS)

Wu, Honglu; Durante, Marco; Furusawa, Yoshiya; George, Kerry; Kawata, Tetsuya; Cucinotta, Francis A.

2003-01-01

Confluent human fibroblast cells (AG1522) were irradiated with gamma rays, 490 MeV/nucleon silicon ions, or iron ions at either 200 or 500 MeV/nucleon. The cells were allowed to repair at 37 degrees C for 24 h after exposure, and a chemically induced premature chromosome condensation (PCC) technique was used to condense chromosomes in the G2 phase of the cell cycle. Incomplete and complex exchanges were analyzed in the irradiated samples. To verify that chromosomal breaks were truly unrejoined, chromosome aberrations were analyzed using a combination of whole-chromosome specific probes and probes specific for the telomere region of the chromosome. Results showed that the frequency of unrejoined chromosome breaks was higher after irradiation with the heavy ions of high LET, and consequently the ratio of incomplete to complete exchanges increased steadily with LET up to 440 keV/microm, the highest LET included in the present study. For samples exposed to 200 MeV/nucleon iron ions, chromosome aberrations were analyzed using the multicolor FISH (mFISH) technique, which allows identification of both complex and truly incomplete exchanges. Results of the mFISH study showed that 0.7 and 3 Gy iron ions produced similar ratios of complex to simple exchanges and incomplete to complete exchanges; these ratios were higher than those obtained after exposure to 6 Gy gamma rays. After 0.7 Gy of iron ions, most complex aberrations were found to involve three or four chromosomes, which is a likely indication of the maximum number of chromosome domains traversed by a single iron-ion track.

INFOTERRA: Gateway to International Environmental Information.

ERIC Educational Resources Information Center

McNamar, Emma J.

1993-01-01

Describes the components, collaborators, and services of INFOTERRA, an environmental information exchange network designed to facilitate the exchange of information among countries and to promote knowledge with countries of the international environmental situation. (MDH)

Social organization influences the exchange and species richness of medicinal plants in Amazonian homegardens.

PubMed

2016-03-01

Medicinal plants provide indigenous and peasant communities worldwide with means to meet their healthcare needs. Homegardens often act as medicine cabinets, providing easily accessible medicinal plants for household needs. Social structure and social exchanges have been proposed as factors influencing the species diversity that people maintain in their homegardens. Here, we assess the association between the exchange of medicinal knowledge and plant material and medicinal plant richness in homegardens. Using Tsimane' Amazonian homegardens as a case study, we explore whether social organization shapes exchanges of medicinal plant knowledge and medicinal plant material. We also use network centrality measures to evaluate people's location and performance in medicinal plant knowledge and plant material exchange networks. Our results suggest that social organization, specifically kinship and gender relations, influences medicinal plant exchange patterns significantly. Homegardens total and medicinal plant species richness are related to gardeners' centrality in the networks, whereby people with greater centrality maintain greater plant richness. Thus, together with agroecological conditions, social relations among gardeners and the culturally specific social structure seem to be important determinants of plant richness in homegardens. Understanding which factors pattern general species diversity in tropical homegardens, and medicinal plant diversity in particular, can help policy makers, health providers, and local communities to understand better how to promote and preserve medicinal plants in situ. Biocultural approaches that are also gender sensitive offer a culturally appropriate means to reduce the global and local loss of both biological and cultural diversity.

DNA damage and repair in oncogenic transformation by heavy ion radiation

NASA Technical Reports Server (NTRS)

Yang, T. C.; Mei, M.; George, K. A.; Craise, L. M.

1996-01-01

Energetic heavy ions are present in galactic cosmic rays and solar particle events. One of the most important late effects in risk assessment is carcinogenesis. We have studied the carcinogenic effects of heavy ions at the cellular and molecular levels and have obtained quantitative data on dose-response curves and on the repair of oncogenic lesions for heavy particles with various charges and energies. Studies with repair inhibitors and restriction endonucleases indicated that for oncogenic transformation DNA is the primary target. Results from heavy ion experiments showed that the cross section increased with LET and reached a maximum value of about 0.02 micrometer2 at about 500 keV/micrometer. This limited size of cross section suggests that only a fraction of cellular genomic DNA is important in radiogenic transformation. Free radical scavengers, such as DMSO, do not give any effect on induction of oncogenic transformation by 600 MeV/u iron particles, suggesting most oncogenic damage induced by high-LET heavy ions is through direct action. Repair studies with stationary phase cells showed that the amount of reparable oncogenic lesions decreased with an increase of LET and that heavy ions with LET greater than 200 keV/micrometer produced only irreparable oncogenic damage. An enhancement effect for oncogenic transformation was observed in cells irradiated by low-dose-rate argon ions (400 MeV/u; 120 keV/micrometer). Chromosomal aberrations, such as translocation and deletion, but not sister chromatid exchange, are essential for heavy-ion-induced oncogenic transformation. The basic mechanism(s) of misrepair of DNA damage, which form oncogenic lesions, is unknown.

PheniX: A New Vision for the Hard X-ray Sky

NASA Technical Reports Server (NTRS)

Roques, Jean-Pierre; Jourdain, Elisabeth; Bassani, Loredana; Bazzano, Angela; Belmont, Renaud; Bird, A. J.; Caroli, E.; Chauvin, M.; Clark, D.; Gehrels, N.;

PheniX: a new vision for the hard X-ray sky

NASA Astrophysics Data System (ADS)

Roques, Jean-Pierre; Jourdain, Elisabeth; Bassani, Loredana; Bazzano, Angela; Belmont, Renaud; Bird, A. J.; Caroli, E.; Chauvin, M.; Clark, D.; Gehrels, N.; Goerlach, U.; Harrisson, F.; Laurent, P.; Malzac, J.; Medina, P.; Merloni, A.; Paltani, S.; Stephen, J.; Ubertini, P.; Wilms, J.

2012-10-01

We are proposing a mission devoted to high energy X-ray astronomy that is based on a focusing telescope operating in the 1-200 keV energy range but optimized for the hard X-ray range. The main scientific topics concern: Physics of compact objects: The proximity of compact objects provides a unique laboratory to study matter and radiation in extreme conditions of temperature and density in strong gravitational environment. The emission of high energy photons from these objects is far from being understood. The unprecedented sensitivity in the high energy domain will allow a precise determination of the non-thermal processes at work in the vicinity of compact objects. The full 1-200 keV energy coverage will be ideal to disentangle the emission processes produced in the spacetime regions most affected by strong-gravity, as well as the physical links: disk-thermal emission-iron line-comptonisation-reflection-non-thermal emission-jets. Neutron stars-magnetic field-cyclotron lines: Time resolved spectroscopy (and polarimetry) at ultra-high sensitivity of AXP, milliseconds pulsars and magnetars will give new tools to study the role of the synchrotron processes at work in these objects. Cyclotron lines-direct measurement of magnetic filed-equation of state constraints-short bursts-giant flares could all be studied with great details. AGN: The large sensitivity improvement will provide detailed spectral properties of the high energy emission of AGN's. This will give a fresh look to the connection between accretion and jet emission and will provide a new understanding of the physical processes at work. Detection of high-redshift active nuclei in this energy range will allow to introduce an evolutionary aspect to high-energy studies of AGN, probing directly the origin of the Cosmic X-ray Background also in the non-thermal range (> 20 keV). Element formation-Supernovae: The energy resolution achievable for this mission (<0.5 keV) and a large high energy effective area are ideally suited for the 44Ti line study (68 and 78 keV). This radioactive nuclei emission will give an estimate of their quantities and speed in their environment. In addition the study of the spatial structure and spectral emission of SNR will advance our knowledge of the dynamics of supernovae explosions, of particles acceleration mechanisms and how the elements are released in the interstellar medium. Instrumental design: The progress of X-ray focusing optics techniques allows a major step in the instrumental design: the collecting area becomes independent of the detection area. This drastically reduces the instrumental background and will open a new era. The optics will be based on depth-graded multi-layer mirrors in a Wolter I configuration. To obtain a significant effective area in the hundred of keV range a focal length in the 40-50 meters range (attainable with a deployable mast) is needed. In addition such a mission could benefit from recent progress made on mirror coating. We propose to cover the 1-200 keV energy range with a single detector, a double-sided Germanium strip detector operating at 80 K. The main features will be: (a) good energy resolution (.150 keV at 5 keV and <.5 keV at 100 keV), (b) 3 dimensional event localization with a low number of electronic chains, (c) background rejection by the 3D localization, (d) polarisation capabilities in the Compton regime.

Born-Oppenheimer Interatomic Forces from Simple, Local Kinetic Energy Density Functionals

NASA Astrophysics Data System (ADS)

Karasiev, V. V.; Trickey, S. B.; Harris, Frank E.

2006-10-01

Rapid calculation of Born-Oppenheimer (B-O) forces is essential for driving the so-called quantum region of a multi-scale molecular dynamics simulation. The success of density functional theory (DFT) with modern exchange-correlation approximations makes DFT an appealing choice for this role. But conventional Kohn-Sham DFT, even with various linear-scaling implementations, really is not fast enough to meet the challenge of complicated chemo-mechanical phenomena (e.g. stress-induced cracking in the presence of a solvent). Moreover, those schemes involve approximations that are difficult to check practically or to validate formally. A popular alternative, Car-Parrinello dynamics, does not guarantee motion on the B-O surface. Another approach, orbital-free DFT, is appealing but has proven difficult to implement because of the challenge of constructing reliable orbital-free (OF) approximations to the kinetic energy (KE) functional. To be maximally useful for multi-scale simulations, an OF-KE functional must be local (i.e. one-point). This requirement eliminates the two-point functionals designed to have proper linear-response behavior in the weakly inhomogeneous limit. In the face of these difficulties, we demonstrate that there is a way forward. By requiring only that the approximate functional deliver high-quality forces, by exploiting the “conjointness” hypothesis of Lee, Lee, and Parr, by enforcing a basic positivity constraint, and by parameterizing to a carefully selected, small set of molecules we are able to generate a KE functional that does a good job of describing various H q Si m O n clusters as well as CO (providing encouraging evidence of transferability). In addition to that positive result, we discuss several major negative results. First is definitive proof that the conjointness hypothesis is not correct, but nevertheless is useful. The second is the failure of a considerable variety of published KE functionals of the generalized gradient approximation type. Those functionals yield no minimum on the energy surface and give completely incorrect forces. In all cases, the problem can be traced to incorrect behavior of the functionals near the nuclei. Third, the seemingly obvious strategy of direct numerical fitting of OF-KE functional parameters to reproduce the energy surface of selected molecules is unsuccessful. The functionals that result are completely untransferable.

Néel walls between tailored parallel-stripe domains in IrMn/CoFe exchange bias layers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ueltzhöffer, Timo, E-mail: timo.ueltzhoeffer@physik.uni-kassel.de; Schmidt, Christoph; Ehresmann, Arno

Tailored parallel-stripe magnetic domains with antiparallel magnetizations in adjacent domains along the long stripe axis have been fabricated in an IrMn/CoFe Exchange Bias thin film system by 10 keV He{sup +}-ion bombardment induced magnetic patterning. Domain walls between these domains are of Néel type and asymmetric as they separate domains of different anisotropies. X-ray magnetic circular dichroism asymmetry images were obtained by x-ray photoelectron emission microscopy at the Co/Fe L{sub 3} edges at the synchrotron radiation source BESSY II. They revealed Néel-wall tail widths of 1 μm in agreement with the results of a model that was modified in order to describemore » such walls. Similarly obtained domain core widths show a discrepancy to values estimated from the model, but could be explained by experimental broadening. The rotation senses in adjacent walls were determined, yielding unwinding domain walls with non-interacting walls in this layer system.« less

Islands of knowledge: science and agriculture in the history of Latin America and the Caribbean.

PubMed

Fernández Prieto, Leida

2013-12-01

This essay explores the participation of Latin America and the Caribbean in the construction and circulation of tropical agricultural science during the nineteenth century and the first half of the twentieth century. It uses the term "islands of knowledge" to underscore the idea that each producing region across the global tropics, including Latin America and the Caribbean, was instrumental in the creation, adoption, and application of scientific procedures. At the same time, it emphasizes the value of interchange and interconnection between these regions, as well as the many and heterogeneous local areas, for analyzing what it calls "global archipelago agricultural scientific knowledge." This focus challenges the traditional center/periphery hierarchy and opens it to a wider vision of science and practice in agriculture. This essay shows how writing in related areas of research--specifically, commodity histories, biological exchange studies, and knowledge exchange studies--introduces approaches and case studies that are useful for the history of tropical agricultural science. In particular, this work provides analytical frameworks for developing studies of exchanges across the Global South.

The Characteristic Pitch Angle Distributions of 1 eV to 600 keV Protons Near the Equator Based On Van Allen Probes Observations

DOE PAGES

Yue, Chao; Bortnik, Jacob; Thorne, Richard M.; ...

2017-08-31

Understanding the source and loss processes of various plasma populations is greatly aided by having accurate knowledge of their pitch angle distributions (PADs). Here we statistically analyze ~1 eV to 600 keV hydrogen (H+) PADs near the geomagnetic equator in the inner magnetosphere based on Van Allen Probes measurements, to comprehensively investigate how the H+ PADs vary with different energies, magnetic local times (MLTs), L shells, and geomagnetic conditions. Our survey clearly indicates four distinct populations with different PADs: a pancake distribution of the plasmaspheric H+ at low L shells except for dawn sector; a bidirectional field-aligned distribution of themore » warm plasma cloak; pancake or isotropic distributions of ring current H+; radiation belt particles show pancake, butterfly, and isotropic distributions depending on their energy, MLT, and L shell. Meanwhile, the pancake distribution of ring current H+ moves to lower energies as shell increases, which is primarily caused by adiabatic transport. Furthermore, energetic H+ (>10 keV) PADs become more isotropic following the substorm injections, indicating wave-particle interactions. The radiation belt H+ butterfly distributions are identified in a narrow energy range of 100 < E < 400 keV at large L ( L > 5), which are less significant during quiet times and extend from dusk to dawn sector through midnight during substorms. In conclusion, the different PADs near the equator provide clues of the underlying physical processes that produce the dynamics of these different populations.« less

The Characteristic Pitch Angle Distributions of 1 eV to 600 keV Protons Near the Equator Based On Van Allen Probes Observations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yue, Chao; Bortnik, Jacob; Thorne, Richard M.

Understanding the source and loss processes of various plasma populations is greatly aided by having accurate knowledge of their pitch angle distributions (PADs). Here we statistically analyze ~1 eV to 600 keV hydrogen (H+) PADs near the geomagnetic equator in the inner magnetosphere based on Van Allen Probes measurements, to comprehensively investigate how the H+ PADs vary with different energies, magnetic local times (MLTs), L shells, and geomagnetic conditions. Our survey clearly indicates four distinct populations with different PADs: a pancake distribution of the plasmaspheric H+ at low L shells except for dawn sector; a bidirectional field-aligned distribution of themore » warm plasma cloak; pancake or isotropic distributions of ring current H+; radiation belt particles show pancake, butterfly, and isotropic distributions depending on their energy, MLT, and L shell. Meanwhile, the pancake distribution of ring current H+ moves to lower energies as shell increases, which is primarily caused by adiabatic transport. Furthermore, energetic H+ (>10 keV) PADs become more isotropic following the substorm injections, indicating wave-particle interactions. The radiation belt H+ butterfly distributions are identified in a narrow energy range of 100 < E < 400 keV at large L ( L > 5), which are less significant during quiet times and extend from dusk to dawn sector through midnight during substorms. In conclusion, the different PADs near the equator provide clues of the underlying physical processes that produce the dynamics of these different populations.« less

Analysis of Heavy Ion-Induced Chromosome Aberrations in Human Fibroblast Cells Using In Situ Hybridization

NASA Technical Reports Server (NTRS)

Wu, Honglu; Durante, Marco; Furusawa, Yoshiya; George, Kerry; Kawata, Tetsuya; Cucinotta, Francis A.

2003-01-01

Confluent human fibroblast cells (AG1522) were irradiated with gamma rays, 490 MeV/nucleon Si, or with Fe ions at either 200 or 500 MeV/nucleon. The cells were allowed to repair at 37 0 C for 24 hours after exposure, and a chemically induced premature chromosome condensation (PCC) technique was used to condense chromosomes in the G2 phase of the cell cycle. Unrejoined chromosomal breaks and complex exchanges were analyzed in the irradiated samples. In order to verify that chromosomal breaks were truly unrejoined, chromosome aberrations were analyzed using a combination of whole chromosome specific probes and probes specific for the telomere region of the chromosome. Results showed that the frequency of unrejoined chromosome breaks was higher after high-LET radiation, and consequently, the ratio of incomplete to complete exchanges increased steadily with LET up to 440 keV/micron, the highest LET value in the present study. For samples exposed to 200 MeV/nucleon Fe ions, chromosome aberrations were analyzed using the multicolor FISH (mFISH) technique that allows identification of both complex and truly incomplete exchanges. Results of the mFISH study showed that 0.7 and 3 Gy dose of the Fe ions produced similar ratios of complex to simple exchanges and incomplete to complete exchanges, values for which were higher than those obtained after a 6 Gy gamma exposure. After 0.7 Gy of Fe ions, most complex aberrations were found to involve three or four chromosomes, indicating the maximum number of chromosome domains traversed by a single Fe ion track. 2

Intershell correlations in Compton photon scattering by an atom

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hopersky, Alexey N.; Nadolinsky, Alexey M.; Novikov, Sergey A.

The role of the intershell correlation effect is theoretically investigated using the example of the Ne atom in nonresonance Compton high-energy x-ray photon scattering by a free atom. The calculation results qualitatively reproduce the same results in the formalism of the generalized oscillator strength and the random phase approximation with exchange for the Compton photon and electron scattering by an atom; when the incident photon energy is 11 keV and the scattering angle is 90 deg., they correspond well with the results of the synchrotron experiment presented in the work by Jung et al. [Phys. Rev. Lett. 81, 1596 (1998)].

Inside Out: Knowledge Brokering by Short-Term Policy Placements

ERIC Educational Resources Information Center

Bruce, Ann; O'Callaghan, Kenneth

2016-01-01

The evidence-policy interface is important for delivery of sustainable development policy. We examine one specific form of knowledge brokering, the temporary placement of academic research scientists in UK policy arenas. We argue that successful knowledge brokerage depends on establishing social processes critical to effective knowledge exchange.…

Mercury exchange at the air-water-soil interface: an overview of methods.

PubMed

Fang, Fengman; Wang, Qichao; Liu, Ruhai

2002-06-12

An attempt is made to assess the present knowledge about the methods of determining mercury (Hg) exchange at the air-water-soil interface during the past 20 years. Methods determining processes of wet and dry removal/deposition of atmospheric Hg to aquatic and terrestrial ecosystems, as well as methods determining Hg emission fluxes to the atmosphere from natural surfaces (soil and water) are discussed. On the basis of the impressive advances that have been made in the areas relating to Hg exchange among air-soil-water interfaces, we analyzed existing problems and shortcomings in our current knowledge. In addition, some important fields worth further research are discussed and proposed.

Carbon dioxide exchange between an undisturbed old-growth temperate forest and the atmosphere

Treesearch

D.Y. Hollinger; F.M. Kelliher; J.N. Byers; J.E. Hunt; T.M. McSeveny; P.L. Weir

1994-01-01

We used the eddy-correlation technique to investigate the exchange of C02 between an undisturbed old-growth forest and the atmosphere at a remote Southern Hemisphere site on 15 d between 1989 and 1990. Our goal was to determine how environmental factors regulate ecosystem CO2 exchange, and to test whether present knowledge...

Measuring Collaboration and Communication to Increase Implementation of Evidence-Based Practices: The Cultural Exchange Inventory

ERIC Educational Resources Information Center

Palinkas, Lawrence A.; Garcia, Antonio; Aarons, Gregory; Finno-Velasquez, Megan; Fuentes, Dahlia; Holloway, Ian; Chamberlain, Patricia

2018-01-01

The Cultural Exchange Inventory (CEI) is a 15-item instrument designed to measure the process (7 items) and outcomes (8 items) of exchanges of knowledge, attitudes and practices between members of different organisations collaborating in implementing evidence-based practice. We conducted principal axis factor analyses and parallel analyses of data…

The Business School in Transition: New Opportunities in Management Development, Knowledge Transfer and Knowledge Creation

ERIC Educational Resources Information Center

Harrington, Denis; Kearney, Arthur

2011-01-01

Purpose: This paper aims to consider the extent to which business school transition has created new opportunities in management development, knowledge transfer and knowledge creation. Design/methodology/approach: The paper is a critical review of knowledge exchange in a business school context with a particular focus on the "translation or…

A "Knowledge Trading Game" for Collaborative Design Learning in an Architectural Design Studio

ERIC Educational Resources Information Center

Wang, Wan-Ling; Shih, Shen-Guan; Chien, Sheng-Fen

2010-01-01

Knowledge-sharing and resource exchange are the key to the success of collaborative design learning. In an architectural design studio, design knowledge entails learning efforts that need to accumulate and recombine dispersed and complementary pieces of knowledge. In this research, firstly, "Knowledge Trading Game" is proposed to be a way for…

In-situ observations of a bi-modal ion distribution in the outer coma of comet P/Halley

NASA Technical Reports Server (NTRS)

Thomsen, M. F.; Feldman, W. C.; Wilken, B.; Jockers, K.; Stuedemann, W.

1987-01-01

Observations obtained by the Johnstone Plasma Analyzer on the Giotto fly-by of comet Halley showed a fairly sudden decrease in the count rate of energetic (about 30 KeV) water-group ions inside about 500,000 km from the nucleus. This decrease was accompanied by the appearance of a new water-group ion population at slightly lower energies (less than 10 KeV). Close inspection reveals that this lower-energy peak was also present somewhat earlier in the postshock flow but only became prominent near the sudden transition just described. It is shown that the observed bimodal ion distribution is well explained in terms of the velocity history of the accreting solar wind flow in the outer coma. The decline in count rate of the energetic pick-up distribution is due to a relatively sudden slowing of the bulk flow there and not to a loss of particles. Hence, charge-exchange cooling of the flow is probably not important at these distances from the nucleus. The observations suggest that pitch-angle scattering is fairly efficient at least after the bow shock, but that energy diffusion is probably not very efficient.

Design of a retarding potential grid system for a neutral particle analyzer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Titus, J. B., E-mail: jtitus@wisc.edu; Mezonlin, E. D.; Anderson, J. K.

2014-11-15

The ion energy distribution in a magnetically confined plasma can be inferred from charge exchange neutral particles. On the Madison Symmetric Torus (MST), deuterium neutrals are measured by the Florida A and M University compact neutral particle analyzer (CNPA) and the advanced neutral particle analyzer (ANPA). The CNPA energy range covers the bulk deuterium ions to the beginning of the fast ion tail (0.34–5.2 keV) with high-energy resolution (25 channels) while the ANPA covers the vast majority of the fast ion tail distribution (∼10–45 keV) with low energy resolution (10 channels). Though the ANPA has provided insight into fast ionmore » energization in MST plasma, more can be gained by increasing the energy resolution in that energy range. To utilize the energy resolution of the CNPA, fast ions can be retarded by an electric potential well, enabling their detection by the diagnostic. The ion energy distribution can be measured with arbitrary resolution by combining data from many similar MST discharges with different energy ranges on the CNPA, providing further insight into ion energization and fast ion dynamics on MST.« less

Obstacles of Implementing the Science Curricula of the Basic Stage as Perceived by the Teachers in a Jordanian Town

ERIC Educational Resources Information Center

Ayasra, Ahmad

2015-01-01

This study aimed to investigate obstacles that prevent implementation of science curriculum which was developed within the Education Reform for the Knowledge Economy project (ErfKE). To achieve this, a purposeful sample consisted of four teachers of science for the basic stage in the town located in the north of Jordan in the first semester of the…

A Social-Learning Approach to Hazard-Related Knowledge Exchange: Boundary Workers at the Geoscience-Humanitarian Interface

NASA Astrophysics Data System (ADS)

Quinn, Keira; Hope, Max; McCloskey, John

2014-05-01

A Social-Learning Approach to Hazard-Related Knowledge Exchange: Boundary Workers at the Geoscience-Humanitarian Interface Keira Quinn (1), Dr Max Hope (1), Professor John McCloskey (1). (1)University of Ulster Peer-reviewed science has the potential to guide policy-makers and practitioners in developing robust responses to social problems and issues. Despite advances in hazard-related science, it can often be a challenge to translate findings into useful social applications. With natural hazards affecting 2.9 billion people between 2000 and 2012 the need for hazard science to be effectively communicated is undeniable. This is particularly so in humanitarian contexts as non-governmental organisations (NGOs) play a key role in the poorer nations most affected by natural disasters. Past methods of 'knowledge transfer' have tended to lead to misinterpretations and misrepresentations of science to the extent that it is often used incorrectly or not at all. 'Knowledge exchange' is currently heralded as a more effective means of bringing about successful communication and understanding, and is characterised by the presence of shared learning. Central to a knowledge exchange approach is an understanding of the social and organisational contexts within which learning takes place. Here we use Etienne Wenger's social-learning approach to analyse selected aspects of the social context influencing knowledge exchange across the geoscience-humanitarian interface. For Wenger (2000) Communities of Practice (CoP) are bounded organisational and social groups united by their own distinct values, goals and ways of working. The boundaries surrounding CoPs can act as barriers to knowledge exchange but can also create opportunities for new shared learning by challenging existing perspectives and practice. Drawing on the findings of ongoing qualitative research into communication and learning between earthquake scientists and humanitarian NGOs in UK/Ireland, this paper outlines a number of key features of geoscience and humanitarian Communities of Practice. It focuses on the barriers to and enablers of learning on the boundaries between CoPs and explores the important role played by boundary workers/brokers at this interface. Wenger's (2000) typology of knowledge brokers is used to analyse the different forms this role can take and identify the challenges that hinder it. For example, boundary workers often find themselves in a 'no man's land' between CoP, where their efforts are not recognised or rewarded by either community of practice. We conclude by drawing out wider conclusions on the potential for boundary workers to bridge the science-policy-practice interface particularly ways of developing appropriate boundary infrastructure (for example, recognised career paths, funding mechanisms and organisational support structures).

Knowledge diffusion of dynamical network in terms of interaction frequency.

PubMed

Liu, Jian-Guo; Zhou, Qing; Guo, Qiang; Yang, Zhen-Hua; Xie, Fei; Han, Jing-Ti

2017-09-07

In this paper, we present a knowledge diffusion (SKD) model for dynamic networks by taking into account the interaction frequency which always used to measure the social closeness. A set of agents, which are initially interconnected to form a random network, either exchange knowledge with their neighbors or move toward a new location through an edge-rewiring procedure. The activity of knowledge exchange between agents is determined by a knowledge transfer rule that the target node would preferentially select one neighbor node to transfer knowledge with probability p according to their interaction frequency instead of the knowledge distance, otherwise, the target node would build a new link with its second-order neighbor preferentially or select one node in the system randomly with probability 1 - p. The simulation results show that, comparing with the Null model defined by the random selection mechanism and the traditional knowledge diffusion (TKD) model driven by knowledge distance, the knowledge would spread more fast based on SKD driven by interaction frequency. In particular, the network structure of SKD would evolve as an assortative one, which is a fundamental feature of social networks. This work would be helpful for deeply understanding the coevolution of the knowledge diffusion and network structure.

Application of Kansei engineering and data mining in the Thai ceramic manufacturing

NASA Astrophysics Data System (ADS)

Kittidecha, Chaiwat; Yamada, Koichi

2018-01-01

Ceramic is one of the highly competitive products in Thailand. Many Thai ceramic companies are attempting to know the customer needs and perceptions for making favorite products. To know customer needs is the target of designers and to develop a product that must satisfy customers. This research is applied Kansei Engineering (KE) and Data Mining (DM) into the customer driven product design process. KE can translate customer emotions into the product attributes. This method determines the relationships between customer feelings or Kansei words and the design attributes. Decision tree J48 and Class association rule which implemented through Waikato Environment for Knowledge Analysis (WEKA) software are used to generate a predictive model and to find the appropriate rules. In this experiment, the emotion scores were rated by 37 participants for training data and 16 participants for test data. 6 Kansei words were selected, namely, attractive, ease of drinking, ease of handing, quality, modern and durable. 10 mugs were selected as product samples. The results of this study indicate that the proposed models and rules can interpret the design product elements affecting the customer emotions. Finally, this study provides useful understanding for the application DM in KE and can be applied to a variety of design cases.

An X-ray survey of the Central Molecular Zone: variability of the Fe K emission line

NASA Astrophysics Data System (ADS)

Terrier, R.; Clavel, M.

2017-10-01

The observation of varying non-thermal diffuse X-ray emission molecular complexes in the central 300 pc has been interpreted as delayed reflection of a past illumination by bright outbursts of the Galactic SMBH. Determining its light curve over the past centuries requires a detailed knowledge of the gas distribution, which is still lacking. Nevertheless, variability of the reflected emission all over of the central 300 pc, in particular in the 6.4 keV Fe K line, can bring strong constraints. Thanks to a deep scan of the inner 300 pc with XMM in 2012 and to a similar albeit more shallow scan performed in 2000-2001, we performed a detailed study of variability of the 6.4 keV line emission in the region, which we present here. We show that the overall 6.4 keV emission does not strongly vary on average, but variations are very pronounced on smaller scales. The absence of bright steady emission argues against the presence of an echo from an event of multi-centennial duration and most, if not all, of the emission can likely be explained by a limited number of relatively short (i.e. up to 10 years) events.

Negotiating multisectoral evidence: a qualitative study of knowledge exchange at the intersection of transport and public health.

PubMed

Guell, Cornelia; Mackett, Roger; Ogilvie, David

2017-01-05

For the prevention and control of chronic diseases, two strategies are frequently highlighted: that public health should be evidence based, and that it should develop a multisectoral approach. At the end of a natural experimental study of the health impacts of new transport infrastructure, we took the opportunity of a knowledge exchange forum to explore how stakeholders assessed, negotiated and intended to apply multisectoral evidence in policy and practice at the intersection of transport and health. We aimed to better understand the challenges they faced in knowledge exchange, as well as their everyday experiences with working in multisectoral remits. In 2015, we conducted participant observation during an interactive event with 41 stakeholders from national and local government, the third sector and academia in Cambridge, UK. Formal and informal interactions between stakeholders were recorded in observational field notes. We also conducted 18 semistructured interviews reflecting on the event and on knowledge exchange in general. We found that stakeholders negotiated a variety of challenges. First, stakeholders had to negotiate relatively new formal and informal multisectoral remits; and how to reconcile the differing expectations of transport specialists, who tended to emphasise the importance of precedence in guiding action, and health specialists' concern for the rigour and synthesis of research evidence. Second, research in this field involved complex study designs, and often produced evidence with uncertain transferability to other settings. Third, health outcomes of transport schemes had political traction and were used strategically but not easily translated into cost-benefit ratios. Finally, knowledge exchange meant multiple directions of influence. Stakeholders were concerned that researchers did not always have skills to translate their findings into understandable evidence, and some stakeholders would welcome opportunities to influence research agendas. This case study of stakeholders' experiences indicates that multisectoral research, practice and policymaking requires the ability and capacity to locate, understand and communicate complex evidence from a variety of disciplines, and integrate different types of evidence into clear business cases beyond sectoral boundaries.

The development of an internet-based knowledge exchange platform for pediatric critical care clinicians worldwide*.

PubMed

Wolbrink, Traci A; Kissoon, Niranjan; Burns, Jeffrey P

2014-03-01

Advances in Internet technology now enable unprecedented global collaboration and collective knowledge exchange. Up to this time, there have been limited efforts to use these technologies to actively promote knowledge exchange across the global pediatric critical care community. To develop an open-access, peer-reviewed, not-for-profit Internet-based learning application, OPENPediatrics, a collaborative effort with the World Federation of Pediatric Intensive and Critical Care Societies, was designed to promote postgraduate educational knowledge exchange for physicians, nurses, and others caring for critically ill children worldwide. Description of program development. International multicenter tertiary pediatric critical care units across six continents. Multidisciplinary pediatric critical care providers. A software application, providing information on demand, curricular pathways, and videoconferencing, downloaded to a local computer. In 2010, a survey assessing postgraduate educational needs was distributed through World Federation of Pediatric Intensive and Critical Care Societies to constituent societies. Four hundred and twenty-nine critical care providers from 49 countries responded to the single e-mail survey request. Respondents included 68% physicians and 28% nurses who care for critically ill children. Fifty-two percent of respondents reported accessing the Internet at least weekly to obtain professional educational information. The five highest requests were for educational content on respiratory care [mechanical ventilation] (48% [38%]), sepsis (28%), neurology (25%), cardiology (14%), extracorporeal membrane oxygenation (10%), and ethics (8%). Based on these findings, and in collaboration with researchers in adult learning and online courseware, an application was developed and is currently being used by 770 registered users in 60 countries. We describe here the development and implementation of an Internet-based application which is among the first efforts designed to promote global knowledge exchange for physicians and nurses caring for critically ill children. This application has the potential to evolve new methods in postgraduate education. Ongoing assessment of the efficacy of Internet-based learning platforms will be necessary.

An Anesthesia Preinduction Checklist to Improve Information Exchange, Knowledge of Critical Information, Perception of Safety, and Possibly Perception of Teamwork in Anesthesia Teams.

PubMed

Tscholl, David W; Weiss, Mona; Kolbe, Michaela; Staender, Sven; Seifert, Burkhardt; Landert, Daniel; Grande, Bastian; Spahn, Donat R; Noethiger, Christoph B

2015-10-01

An anesthesia preinduction checklist (APIC) to be performed before anesthesia induction was introduced and evaluated with respect to 5 team-level outcomes, each being a surrogate end point for patient safety: information exchange (the percentage of checklist items exchanged by a team, out of 12 total items); knowledge of critical information (the percentage of critical information items out of 5 total items such as allergies, reported as known by the members of a team); team members' perceptions of safety (the median scores given by the members of a team on a continuous rating scale); their perception of teamwork (the median scores given by the members of a team on a continuous rating scale); and clinical performance (the percentage of completed items out of 14 required tasks, e.g., suction device checked). A prospective interventional study comparing anesthesia teams using the APIC with a control group not using the APIC was performed using a multimethod design. Trained observers rated information exchange and clinical performance during on-site observations of anesthesia inductions. After the observations, each team member indicated the critical information items they knew and their perceptions of safety and teamwork. One hundred five teams using the APIC were compared with 100 teams not doing so. The medians of the team-level outcome scores in the APIC group versus the control group were as follows: information exchange: 100% vs 33% (P < 0.001), knowledge of critical information: 100% vs 90% (P < 0.001), perception of safety: 91% vs 84% (P < 0.001), perception of teamwork: 90% vs 86% (P = 0.028), and clinical performance: 93% vs 93% (P = 0.60). This study provides empirical evidence that the use of a preinduction checklist significantly improves information exchange, knowledge of critical information, and perception of safety in anesthesia teams-all parameters contributing to patient safety. There was a trend indicating improved perception of teamwork.

Interdisciplinarity and Knowledge Networking: Co-Production of Climate-Authoritative Knowledge in Southern South America

ERIC Educational Resources Information Center

Hidalgo, Cecilia

2016-01-01

Interdisciplinarity and knowledge networking are at the core of current global, regional, and national initiatives concerning climate. Both scientifc knowledge and public participation are essential to enhance the capacity of different sectors and governments to respond to challenges posed by climate variability and change. Exchange and bridge…

The Influence of the Knowledge Society: Trends in Adult Higher Education

ERIC Educational Resources Information Center

Kasworm, Carol

2011-01-01

Current understandings of a knowledge economy have been emerging from two defining forces: the rise in quality and intensity of knowledge as a key commodity for economic development and the increasing globalization through information technology of both knowledge exchange and economic activities. The future of adult higher education is focused on…

The Effectiveness of Web-Based Foreign Exchange Trading Simulation in an International Finance Course

ERIC Educational Resources Information Center

Chou, Chen-Huei; Liu, Hao-Chen

2013-01-01

The purpose of this article is to study if trading simulation is an effective tool to increase students' knowledge of the foreign exchange market. We developed a real-time multiuser web-based trading system that replicates an electronic brokerage foreign exchange market. To assess the effectiveness of the program, we conducted surveys in three…

A Qualitative Study on Knowledge Transfer among Members of the United States Intelligence Community

ERIC Educational Resources Information Center

Keshavarz-Nia, Navid R.

2011-01-01

This study sought to examine the relationship between social interaction and tacit knowledge transfer, as a dyadic exchange of critical knowledge between a Subject Matter Expert (SME) and a Knowledge Recipient (KR). Knowledge was defined as information and know-how, not merely as organized data or a system, but an active social process that was…

Enhancing fire science exchange: The Northern Rockies Fire Science Network [poster

Treesearch

Vita Wright

2011-01-01

The Joint Fire Science Program is developing a national network of knowledge exchange consortia comprised of interested management and science stakeholders working together to tailor and actively demonstrate existing fire science information to benefit management.

Irradiation-induced Ag-colloid formation in ion-exchanged soda-lime glass

NASA Astrophysics Data System (ADS)

Caccavale, F.; De Marchi, G.; Gonella, F.; Mazzoldi, P.; Meneghini, C.; Quaranta, A.; Arnold, G. W.; Battaglin, G.; Mattei, G.

1995-03-01

Ion-exchanged glass samples were obtained by immersing soda-lime slides in molten salt baths of molar concentration in the range 1-20% AgNO 3 in NaNO 3, at temperatures varying from 320 to 350°C, and processing times of the order of a few minutes. Irradiations of exchanged samples were subsequently performed by using H +m, He +, N + ions at different energies in order to obtain comparable projected ranges. The fluence was varied between 5 × 10 15 and 2 × 10 17 ions/cm 2. Most of the samples were treated at current densities lower than 2 μA/cm 2, in order to avoid heating effects. Some samples were irradiated with 4 keV electrons, corresponding to a range of 250 nm. The formation of nanoclusters of radii in the range 1-10 nm has been observed after irradiation, depending on the treatment conditions. The precipitation process is governed by the electronic energy deposition of incident particles. The most desirable results are obtained for helium implants. The process was characterized by the use of Secondary Ion Mass Spectrometry (SIMS) and nuclear techniques (Rutherford Backscattering (RBS), Nuclear Reactions (NRA)), in order to determine concentration-depth profiles and by optical absorption and Transmission Electron Microscopy (TEM) measurements for the silver nanoclusters detection and size evaluation.

STRUCTURE OF THE INTERSTELLAR BOUNDARY EXPLORER RIBBON FROM SECONDARY CHARGE-EXCHANGE AT THE SOLAR–INTERSTELLAR INTERFACE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zirnstein, E. J.; McComas, D. J.; Heerikhuisen, J., E-mail: ezirnstein@swri.edu, E-mail: dmccomas@swri.edu, E-mail: jacob.heerikhuisen@uah.edu

2015-05-01

In 2009, the Interstellar Boundary Explorer discovered a bright “ribbon” of energetic neutral atom (ENA) flux in the energy range ≤0.4–6 keV, encircling a large portion of the sky. This observation was not previously predicted by any models or theories, and since its discovery, it has been the subject of numerous studies of its origin and properties. One of the most studied mechanisms for its creation is the “secondary ENA” process. Here, solar wind ions, neutralized by charge-exchange with interstellar atoms, propagate outside the heliopause; experience two charge-exchange events in the dense outer heliosheath; and then propagate back inside themore » heliosphere, preferentially in the direction perpendicular to the local interstellar magnetic field. This process has been extensively analyzed using state-of-the-art modeling and simulation techniques, but it has been difficult to visualize. In this Letter, we show the three-dimensional structure of the source of the ribbon, providing a physical picture of the spatial and energy scales over which the secondary ENA process occurs. These results help us understand how the ribbon is generated and further supports a secondary ENA process as the leading ribbon source mechanism.« less

X-ray Magnetosheath Emission from Solar Wind Charge Exchange During Two CME Events in 2001

NASA Astrophysics Data System (ADS)

Sembay, S.; Whittaker, I. C.; Read, A.; Carter, J. A.; Milan, S. E.; Palmroth, M.

2016-12-01

Using a combination of the GUMICS-4 MHD model and observed solar wind heavy ion abundances from ACE, we produce case studies looking at X-ray emission from charge exchange in the Earth's magnetosheath. We specifically look in the 0.5-0.7 keV range, which is dominated by highly ionised oxygen emission. Previous studies looking at solar wind charge exchange (SWCX) emission have verified our modelling process via comparison to the XMM-Newton X-ray observatory, and we use the same simulation process here. This study investigates the emission magnitude changes that occur during two coronal mass ejection (CME) events (31 March 2001 and 21 October 2001). As part of this work we also provide a novel masking technique to exclude the plasma of terrestrial origin in the MHD model. As expected the two CME cases examined provide an increased dynamic pressure which pushes the magnetopause closer to the Earth, with a high temporal variation. We show how these changes cause an increase in the peak SWCX emission signature by over an order of magnitude from the quiescent solar wind case. Imaging of this SWCX emission allows a global view of the magnetopause shape and position, a technique planned for future missions such as SMILE (Solar wind Magnetosphere Ionosphere Link Explorer).

Science in the Public Sphere: Greater Sage-grouse Conservation Planning from a Transdisciplinary Perspective

USGS Publications Warehouse

Torregrosa, Alicia; Casazza, Michael L.; Caldwell, Margaret R.; Mathiasmeier, Teresa A.; Morgan, Peter M.; Overton, Cory T.

2010-01-01

Integration of scientific data and adaptive management techniques is critical to the success of species conservation, however, there are uncertainties about effective methods of knowledge exchange between scientists and decisionmakers. The conservation planning and implementation process for Greater Sage-grouse (Centrocercus urophasianus; ) in the Mono Basin, Calif. region, was used as a case study to observe the exchange of scientific information among stakeholders with differing perspectives; resource manager, scientist, public official, rancher, and others. The collaborative development of a risk-simulation model was explored as a tool to transfer knowledge between stakeholders and inform conservation planning and management decisions. Observations compiled using a transdisciplinary approach were used to compare the exchange of information during the collaborative model development and more traditional interactions such as scientist-led presentations at stakeholder meetings. Lack of congruence around knowledge needs and prioritization led to insufficient commitment to completely implement the risk-simulation model. Ethnographic analysis of the case study suggests that further application of epistemic community theory, which posits a strong boundary condition on knowledge transfer, could help support application of risk simulation models in conservation-planning efforts within similarly complex social and bureaucratic landscapes.

Coherent exchange of healthcare knowledge in open systems.

PubMed

Buchan, I; Hanka, R

1997-01-01

This paper outlines design philosophies and methods for healthcare knowledge systems. Clinical priorities for knowledge are discussed in terms of temporal and individual needs. Book centred organisation of healthcare knowledge, which has proven effective in clinical practice, is proposed as the basis of virtual libraries available at the point of care for target groups of healthcare professionals.

Knowledge of tuberculosis among drug users. Relationship to return rates for tuberculosis screening at a syringe exchange.

PubMed

Salomon, N; Perlman, D C; Friedmann, P; Perkins, M P; Ziluck, V; Jarlais, D C; Paone, D

1999-04-01

Tuberculosis is an important health issue among drug users. We sought to evaluate active drug users' (DUs) knowledge of tuberculosis (TB) and to assess the relationship between TB knowledge and attitudes and tuberculin skin test (TST) return rates at a syringe exchange program. DUs were recruited at a syringe exchange program in New York City, were interviewed and offered TSTs, and received $15.00 upon returning for TST reading. The questionnaire evaluated knowledge of TB transmission, prevention, and treatment. From March 13, 1995 to January 31, 1996, 610 of 650 (94%) of DUs approached agreed to participate. Of these, 80% had previous TSTs within the past 2 years and 20% were known to be HIV infected. Almost all knew that TB is contagious and more than two thirds knew that TB is treatable and that TB preventive therapy existed. However, fewer than half knew that HIV-related TB could be treated, 30% thought TB could be treated without a medical doctor, and the majority (70%) thought a reactive TST implied infectivity. The rate of return for TST reading was 93%. In multivariate analysis, those who knew that HIV-related TB was curable were more likely to return for TST reading (odds ratio 2.0; 95% confidence interval 1.04 to 3.95; p = .03). The high acceptance and return rates suggest that TB services can be incorporated into syringe exchange programs. However, several important gaps in TB knowledge existed in this population at high risk of TB, which may impact on adherence and which support the need for TB education for drug users.

Experimental and Numerical Investigation of Guest Molecule Exchange Kinetics based on the 2012 Ignik Sikumi Gas Hydrate Field Trial

NASA Astrophysics Data System (ADS)

Ruprecht Yonkofski, C. M.; Horner, J.; White, M. D.

2015-12-01

In 2012 the U.S. DOE/NETL, ConocoPhillips Company, and Japan Oil, Gas and Metals National Corporation jointly sponsored the first field trial of injecting a mixture of N2-CO2 into a CH4-hydrate bearing formation beneath the permafrost on the Alaska North Slope. Known as the Ignik Sikumi #1 Gas Hydrate Field Trial, this experiment involved three stages: 1) the injection of a N2-CO2 mixture into a targeted hydrate-bearing layer, 2) a 4-day pressurized soaking period, and 3) a sustained depressurization and fluid production period. Data collected during the three stages of the field trial were made available after a thorough quality check. The Ignik Sikumi #1 data set is extensive, but contains no direct evidence of the guest-molecule exchange process. This study uses numerical simulation to provide an interpretation of the CH4/CO2/N2 guest molecule exchange process that occurred at Ignik Sikumi #1. Simulations were further informed by experimental observations. The goal of the scoping experiments was to understand kinetic exchange rates and develop parameters for use in Iġnik Sikumi history match simulations. The experimental procedure involves two main stages: 1) the formation of CH4 hydrate in a consolidated sand column at 750 psi and 2°C and 2) flow-through of a 77.5/22.5 N2/CO2 molar ratio gas mixture across the column. Experiments were run both above and below the hydrate stability zone in order to observe exchange behavior across varying conditions. The numerical simulator, STOMP-HYDT-KE, was then used to match experimental results, specifically fitting kinetic behavior. Once this behavior is understood, it can be applied to field scale models based on Ignik Sikumi #1.

Charge-exchange coupling between pickup ions across the heliopause and its effect on energetic neutral hydrogen flux

DOE PAGES

Zirnstein, Eric J.; Heerikhuisen, J.; Zank, G. P.; ...

2014-02-24

Pickup ions (PUIs) appear to play an integral role in the multi-component nature of the plasma in the interaction between the solar wind (SW) and local interstellar medium (LISM). Three-dimensional (3D) MHD simulations with a kinetic treatment for neutrals and PUIs are currently still not viable. In light of recent energetic neutral atom (ENA) observations by the Interstellar Boundary EXplorer, the purpose of this paper is to illustrate the complex coupling between PUIs across the heliopause (HP) as facilitated by ENAs using estimates of PUI properties extracted from a 3D MHD simulation of the SW-LISM interaction with kinetic neutrals. First,more » we improve upon the multi-component treatment of the inner heliosheath (IHS) plasma from Zank et al. by including the extinction of PUIs through charge-exchange. We find a significant amount of energy is transferred away from hot, termination shock-processed PUIs into a colder, "freshly injected" PUI population. Second, we extend the multi-component approach to estimate ENA flux from the outer heliosheath (OHS), formed from charge-exchange between interstellar hydrogen atoms and energetic PUIs. These PUIs are formed from ENAs in the IHS that crossed the HP and experienced charge-exchange. Lastly, our estimates, based on plasma-neutral simulations of the SW-LISM interaction and a post-processing analysis of ENAs and PUIs, suggest the majority of flux visible at 1 AU from the front of the heliosphere, between ~0.02 and 10 keV, originates from OHS PUIs, indicating strong coupling between the IHS and OHS plasmas through charge-exchange.« less

Voyager in-situ and Cassini Remote Measurements Suggest a Bubble-like Shape for the Global Heliosphere

NASA Astrophysics Data System (ADS)

Dialynas, K.; Krimigis, S. M.; Mitchell, D. G.; Decker, R. B.; Roelof, E. C.

2017-12-01

The Low Energy Charged Particle (LECP) in situ measurements from Voyager 1 and Voyager 2 (V1, V2) have revealed the reservoir of ions and electrons that constitute the heliosheath after crossing the termination shock 35 deg north and 32 deg south of the ecliptic plane at 94 and 84 astronomical units (1 AU=1.5x108 km), respectively. In August 2012, at 121.6 AU, V1 crossed the heliopause to enter the interstellar space, while V2 remains in the heliosheath since 2007. The advent of Energetic Neutral Atom (ENA, produced through charge exchange between ions and neutral particles flowing through the heliosphere) imaging, has revealed the global nature of the heliosheath at both high (5.2-55 keV, Cassini/Ion and Neutral Camera-INCA, from 10 AU) and low (<6 keV, Interstellar Boundary Explorer-IBEX, from 1 AU) energies. The presence of the two Voyagers measuring ions locally in the heliosheath contemporaneously with INCA global imaging through ENA in overlapping energy bands provides a powerful tool for examining the spatial, temporal, and spectral evolution of the source hot plasma ions. Here we report 5.2-55 keV ENA global images of the heliosphere from Cassini/INCA and compare them with V1,2/LECP 28-53 keV ions measured within the heliosheath over a 13-year period (2003-2016). The similarity between the time profiles of ENA and ions establish that the heliosheath ions are the source of ENA. These measurements also demonstrate that the heliosphere responds promptly, within 2-3 years, to outward propagating solar wind changes (manifested in solar sunspot numbers and solar wind energy input) in both the upstream (nose) and downstream (tail) hemispheres. These results, taken together with the V1 measurement of a 0.5 nT interstellar magnetic field and the enhanced ratio between particle pressure and magnetic pressure in the heliosheath, constrain the shape of the global heliosphere: by contrast to the magnetosphere-like heliotail (that past modeling broadly assumed for more than 55 years), a more symmetric, diamagnetic bubble-like heliosphere, with few substantial tail-like features is revealed.

Knowledge exchange throughout the dementia care journey by Canadian rural community-based health care practitioners, persons with dementia, and their care partners: an interpretive descriptive study.

PubMed

Forbes, Dorothy A; Finkelstein, Sara; Blake, Catherine M; Gibson, Maggie; Morgan, Debra G; Markle-Reid, Maureen; Culum, Ivan; Thiessen, Emily

2012-10-01

Accessing, assessing, exchanging, and applying dementia care information can be challenging in rural communities for healthcare practitioners (HCPs), persons with dementia (PWD), and their care partners. The overall purpose of this research was to enable HCPs, care partners, and PWD to use dementia care information more effectively by examining their information needs, how these change over time, and how they access, assess, and apply the knowledge. A qualitative interpretive descriptive approach was used. A convenience sample was initially recruited through study collaborators in Southwestern Ontario, followed by purposive sampling. Nine rural dementia care networks consisting of PWD (n = 5), care partners (n = 14), and HCPs (n = 14) were recruited and 80 interviews were conducted at three time points. Transcripts were coded using Lubrosky's thematic analysis. Six stages of the dementia care journey were identified: (1) recognizing the symptoms; (2) receiving a diagnosis; (3) loss of independence; (4) initiating and using home care and respite services; (5) long-term care (LTC) placement; and (6) decisions related to end-of-life care. Rural care partners identified the need for different types of knowledge during each of these critical decision points of the dementia care journey. They accessed information from family members, friends, local organizations, and dementia internet sites. Persons with dementia tended not to identify the need for dementia care information. The HCPs accessed dementia care information from their own organization, other organizations, and internet sites. Care partners and HCPs assessed the trustworthiness of the information based on whether the source was a well-known agency or their own organization. Barriers to knowledge exchange included: lack of rural community-based services for dementia care; care partners reluctant to seek help and had limited energy; and lack of integration of dementia-related services and supports. Facilitators of knowledge exchange included: rural care partners with healthcare experience who were actively seeking information; development of trusting relationships between HCPs, care partners, and PWD; and formal mechanisms for exchanging information within and across rural community-based organizations. This research illustrates the stages of the dementia care journey, and the types of information typically needed, accessed, assessed, and applied at each stage. Healthcare practitioners can use these findings to support rural care partners in navigating their dementia care journey. Support is needed as care partners often do not have the time, energy, skills, or knowledge to seek out dementia care information independently. In addition, PWD typically do not recognize the need for this knowledge, leaving care partners potentially isolated in this journey. Developing formal linkages within and across rural organizations will facilitate knowledge exchange and the delivery of cost-effective, quality dementia care. However, additional rural community-based resources are urgently needed to implement these recommendations. This may require a redistribution of resources from acute care to rural community care.

Level-energy-dependent mean velocities of excited tungsten atoms sputtered by krypton-ion bombardment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nogami, Keisuke; Sakai, Yasuhiro; Mineta, Shota

2015-11-15

Visible emission spectra were acquired from neutral atoms sputtered by 35–60 keV Kr{sup +} ions from a polycrystalline tungsten surface. Mean velocities of excited tungsten atoms in seven different 6p states were also obtained via the dependence of photon intensities on the distance from the surface. The average velocities parallel to the surface normal varied by factors of 2–4 for atoms in the different 6p energy levels. However, they were almost independent of the incident ion kinetic energy. The 6p-level energy dependence indicated that the velocities of the excited atoms were determined by inelastic processes that involve resonant charge exchange.

Absolute cross-section measurements of inner-shell ionization

NASA Astrophysics Data System (ADS)

Schneider, Hans; Tobehn, Ingo; Ebel, Frank; Hippler, Rainer

1994-12-01

Cross section ratios for K- and L-shell ionization of thin silver and gold targets by positron and electron impact have been determined at projectile energies of 30 70 keV. The experimental results are confirmed by calculations in plane wave Born approximation (PWBA) which include an electron exchange term and account for the deceleration or acceleration of the incident projectile in the nuclear field of the target atom. We report first absolute cross sections for K- and L-shell ionization of silver and gold targets by lepton impact in the threshold region. We have measured the corresponding cross sections for electron (e-) impact with an electron gun and the same experimental set-up.

Room-temperature ferromagnetism observed in C-/N-/O-implanted MgO single crystals

NASA Astrophysics Data System (ADS)

Li, Qiang; Ye, Bonian; Hao, Yingping; Liu, Jiandang; Zhang, Jie; Zhang, Lijuan; Kong, Wei; Weng, Huimin; Ye, Bangjiao

2013-01-01

MgO single crystals were implanted with 70 keV C/N/O ions at room temperature with respective doses of 2 × 1016 and 2 × 1017 ions/cm2. All samples with high-dose implantation showed room temperature hysteresis in magnetization loops. Magnetization and slow positron annihilation measurements confirmed that room temperature ferromagnetism in O-implanted samples was attributed to the presence of Mg vacancies. Furthermore, the introduction of C or N played more effective role in ferromagnetic performance than Mg vacancies. Moreover, the magnetic moment possibly occurred from the localized wave function of unpaired electrons and the exchange interaction formed a long-range magnetic order.

Development of a He- and He0 beam source for alpha particle measurement in a burning plasma.

PubMed

Tanaka, N; Sasao, M; Terai, K; Okamoto, A; Kitajima, S; Yamaoka, H; Wada, M

2012-02-01

Proof of principle experiments of neutral helium beam production for alpha particle diagnostics was carried out on a test stand. Negative helium ions were produced in the Li charge exchange cell, in which stable and long time operation was possible. He(-) beam was accelerated to 157 keV. Finally, He(0) beam was successfully produced after the flight in the drift-tube through the auto-electron-detachment process from He(-) to He(0). A neutral beam detector using a pyroelectric device was also developed to measure He(0) beam intensity. The metastable component in the neutral helium beam was found to be less than 2%.

Breaking the Myths of Rewards: An Exploratory Study of Attitudes about Knowledge Sharing.

ERIC Educational Resources Information Center

Bock, Gee-Woo; Kim, Young-Gul

2002-01-01

Discussion of organizational knowledge sharing focuses on a study of Korean public organizations that investigated factors affecting the individual's knowledge sharing behavior. Highlights include social exchange theory; self-efficacy; theory of reasoned action; and hypothesis testing that showed expected associations and contribution, rather than…

Knowledge Mobilization and Educational Research: Politics, Languages and Responsibilities

ERIC Educational Resources Information Center

Fenwick, Tara, Ed.; Farrell, Lesley, Ed.

2011-01-01

How can educational research have more impact? What processes of knowledge exchange are most effective for increasing the uses of research results? How can research-produced knowledge be better "mobilized" among users such as practicing educators, policy makers, and the public communities? These sorts of questions are commanding urgent…

PERKAM: Personalized Knowledge Awareness Map for Computer Supported Ubiquitous Learning

ERIC Educational Resources Information Center

El-Bishouty, Moushir M.; Ogata, Hiroaki; Yano, Yoneo

2007-01-01

This paper introduces a ubiquitous computing environment in order to support the learners while doing tasks; this environment is called PERKAM (PERsonalized Knowledge Awareness Map). PERKAM allows the learners to share knowledge, interact, collaborate, and exchange individual experiences. It utilizes the RFID ubiquities technology to detect the…

Developing a Climate Change Boundary Organization: the Montana Adaptation Exchange

NASA Astrophysics Data System (ADS)

Whitlock, C. L.; Brooks, S.; Armstrong, T.; Bryan, B.

2016-12-01

Small-population large-area states like Montana are often challenged by a need to offer timely and relevant climate-change information that addresses diverse and widely dispersed stakeholder groups. In Montana, filling the gap between science and various types of decision-makers has motivated development of the first Montana Climate Assessment (MCA1), to be released in 2017 with a focus on climate-change impacts for agricultural, water and forestry sectors. To sustain and build on the MCA1 effort, we are also in the process of creating a Boundary Organization (defined by the National Academy of Sciences) called the Montana Adaptation Exchange (the Exchange); this entity will facilitate the flow of information across the boundaries between science, knowledge and implementation. In Montana, the Exchange brings scientists and practitioners together to seek solutions related to climate-change adaptation and other pressing environmental and social-economic challenges. The Montana Adaptation Exchange (1) is a collaborative partnership of members from the science and practitioner communities under a shared governance and participatory model; (2) presents research that has been vetted by the scientific community at large and represents the current state of knowledge; (3) allows for revision and expansion of assessments like the MCA; (4) communicates relevant, often technical, research and findings to a wide variety of resource managers and other stakeholders; (5) develops and maintains an extensive online database that organizes, regularly updates, and makes research data products readily available; and (6) offers an online portal and expert network of affiliated researchers and climate adaptation specialists to provide effective customer support. Boundary organizations, such as the Montana Adaptation Exchange, offer a scalable path to effectively move from "science to knowledge to action" while also allowing stakeholder needs to help inform research agendas.

Industrial waste exchange: a mechanism for saving energy and money

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gaines, L.L.

1983-01-01

Although considerable savings of both energy and money are possible through waste exchange, several major impediments limit the number of actual exchanges that take place. These impediments include the lack of economical separation technology, the small quantities of material available at each site, restrictive or uncertain regulation, and lack of knowledge on the part of potential waste users. None of these barriers is insurmountable if appropriate action is taken.

Knowledge sharing within organizations: linking art, theory, scenarios and professional experience

NASA Technical Reports Server (NTRS)

Bailey, T.; Burton, Y. C.

2000-01-01

In this discussion, T. Bailey will be addressing the multiple paradigms within organizations using imagery. Dr. Burton will discuss the relationship between these paradigms and social exchanges that lead to knowledge sharing.

Knowledge that Acts: Evaluating the Outcomes of a Knowledge Brokering Intervention in Western Australia's Ningaloo Region

NASA Astrophysics Data System (ADS)

Chapman, Kelly; Boschetti, Fabio; Fulton, Elizabeth; Horwitz, Pierre; Jones, Tod; Scherrer, Pascal; Syme, Geoff

2017-11-01

Knowledge exchange involves a suite of strategies used to bridge the divides between research, policy and practice. The literature is increasingly focused on the notion that knowledge generated by research is more useful when there is significant interaction and knowledge sharing between researchers and research recipients (i.e., stakeholders). This is exemplified by increasing calls for the use of knowledge brokers to facilitate interaction and flow of information between scientists and stakeholder groups, and the integration of scientific and local knowledge. However, most of the environmental management literature focuses on explicit forms of knowledge, leaving unmeasured the tacit relational and reflective forms of knowledge that lead people to change their behaviour. In addition, despite the high transaction costs of knowledge brokering and related stakeholder engagement, there is little research on its effectiveness. We apply Park's Manag Learn 30(2), 141-157 (1999); Knowledge and Participatory Research, London: SAGE Publications (2006) tri-partite knowledge typology as a basis for evaluating the effectiveness of knowledge brokering in the context of a large multi-agency research programme in Australia's Ningaloo coastal region, and for testing the assumption that higher levels of interaction between scientists and stakeholders lead to improved knowledge exchange. While the knowledge brokering intervention substantively increased relational networks between scientists and stakeholders, it did not generate anticipated increases in stakeholder knowledge or research application, indicating that more prolonged stakeholder engagement was required, and/or that there was a flaw in the assumptions underpinning our conceptual framework.

The Power of a Question: A Case Study of Two Organizational Knowledge Capture Systems

NASA Technical Reports Server (NTRS)

Cooper, Lynn P.

2003-01-01

This document represents a presentation regarding organizational knowledge capture systems which was delivered at the HICSS-36 conference held from January 6-9, 2003. An exploratory case study of two knowledge resources is offered. Then, two organizational knowledge capture systems are briefly described: knowledge transfer from practitioner and the use of questions to represent knowledge. Finally, the creation of a database of peer review questions is suggested as a method of promoting organizational discussions and knowledge representation and exchange.

Advancing the hydrogen safety knowledge base

DOE PAGES

Weiner, S. C.

2014-08-29

The International Energy Agency's Hydrogen Implementing Agreement (IEA HIA) was established in 1977 to pursue collaborative hydrogen research and development and information exchange among its member countries. Information and knowledge dissemination is a key aspect of the work within IEA HIA tasks, and case studies, technical reports and presentations/publications often result from the collaborative efforts. The work conducted in hydrogen safety under Task 31 and its predecessor, Task 19, can positively impact the objectives of national programs even in cases for which a specific task report is not published. As a result, the interactions within Task 31 illustrate how technologymore » information and knowledge exchange among participating hydrogen safety experts serve the objectives intended by the IEA HIA.« less

Plasma instability control toward high fluence, high energy x-ray continuum source

NASA Astrophysics Data System (ADS)

Poole, Patrick; Kirkwood, Robert; Wilks, Scott; Blue, Brent

2017-10-01

X-ray source development at Omega and NIF seeks to produce powerful radiation with high conversion efficiency for material effects studies in extreme fluence environments. While current K-shell emission sources can achieve tens of kJ on NIF up to 22 keV, the conversion efficiency drops rapidly for higher Z K-alpha energies. Pulsed power devices are efficient generators of MeV bremsstrahlung x-rays but are unable to produce lower energy photons in isolation, and so a capability gap exists for high fluence x-rays in the 30 - 100 keV range. A continuum source under development utilizes instabilities like Stimulated Raman Scattering (SRS) to generate plasma waves that accelerate electrons into high-Z converter walls. Optimizing instabilities using existing knowledge on their elimination will allow sufficiently hot and high yield electron distributions to create a superior bremsstrahlung x-ray source. An Omega experiment has been performed to investigate the optimization of SRS and high energy x-rays using Au hohlraums with parylene inner lining and foam fills, producing 10× greater x-ray yield at 50 keV than conventional direct drive experiments on the facility. Experiment and simulation details on this campaign will be presented. This work was performed under the auspices of the US DoE by LLNL under Contract No. DE-AC52-07NA27344.

Doppler Broadening and its Contribution to Compton Energy-Absorption Cross Sections: An Analysis of the Compton Component in Terms of Mass-Energy Absorption Coefficient

NASA Astrophysics Data System (ADS)

Rao, D. V.; Takeda, T.; Itai, Y.; Akatsuka, T.; Cesareo, R.; Brunetti, A.; Gigante, G. E.

2002-09-01

Compton energy absorption cross sections are calculated using the formulas based on a relativistic impulse approximation to assess the contribution of Doppler broadening and to examine the Compton profile literature and explore what, if any, effect our knowledge of this line broadening has on the Compton component in terms of mass-energy absorption coefficient. Compton energy-absorption cross sections are evaluated for all elements, Z=1-100, and for photon energies 1 keV-100 MeV. Using these cross sections, the Compton component of the mass-energy absorption coefficient is derived in the energy region from 1 keV to 1 MeV for all the elements Z=1-100. The electron momentum prior to the scattering event should cause a Doppler broadening of the Compton line. The momentum resolution function is evaluated in terms of incident and scattered photon energy and scattering angle. The overall momentum resolution of each contribution is estimated for x-ray and γ-ray energies of experimental interest in the angular region 1°-180°. Also estimated is the Compton broadening using nonrelativistic formula in the angular region 1°-180°, for 17.44, 22.1, 58.83, and 60 keV photons for a few elements (H, C, N, O, P, S, K, and Ca) of biological importance.

Effects of weakly coupled and dense quantum plasmas environments on charge exchange and ionization processes in Na+ + Rb(5s) atom collisions

NASA Astrophysics Data System (ADS)

Pandey, Mukesh Kumar; Lin, Yen-Chang; Ho, Yew Kam

2017-02-01

The effects of weakly coupled or classical and dense quantum plasmas environment on charge exchange and ionization processes in Na+ + Rb(5s) atom collision at keV energy range have been investigated using classical trajectory Monte Carlo (CTMC) method. The interaction of three charged particles are described by the Debye-Hückel screen potential for weakly coupled plasma, whereas exponential cosine-screened Coulomb potential have been used for dense quantum plasma environment and the effects of both conditions on the cross sections are compared. It is found that screening effects on cross sections in high Debye length condition is quite small in both plasma environments. However, enhanced screening effects on cross sections are observed in dense quantum plasmas for low Debye length condition, which becomes more effective while decreasing the Debye length. Also, we have found that our calculated results for plasma-free case are comparable with the available theoretical results. These results are analyzed in light of available theoretical data with the choice of model potentials.

[A network of LIFE projects to promote the transfer and exchange of knowledge on environment and health].

PubMed

Cori, Liliana; Carducci, Annalaura; Donzelli, Gabriele; La Rocca, Cinzia; Bianchi, Fabrizio

2018-01-01

Eleven projects within the LIFE programme (through which the Directorate-General for Environment of the European Commission provides funding for projects aim at protecting environment and nature) addressing environmental-health-related issues have been involved in a collaborative network called KTE LIFE EnvHealth Network. The shared issues tackled by that projects are knowledge transfer and exchange (KTE). The objective of the LIFE programme is to support the implementation of the environmental legislation in the European Union, to provide new tools and knowledge that will help to better protect both the territory and the communities. Transferring knowledge to decision makers, at the appropriate and effective level, is therefore a central function of the projects. The Network promotes national and international networking, which intends to involve other projects, to provide methodological support, to make information and successful practices circulate, with the aim of multiplying the energies of each project involved.

Mode of action of family 10 and 11 endoxylanases on water-unextractable arabinoxylan.

PubMed

Vardakou, Maria; Katapodis, Petros; Samiotaki, Martina; Kekos, Dimitris; Panayotou, George; Christakopoulos, Paul

2003-11-01

Microbial endo-beta-1,4-xylanases (EXs, EC 3.2.1.8) belonging to glycanase families 10 and 11 differ in their action on water-unextractable arabinoxylan (WU-AX). WU-AX was incubated with different levels of a Thermoascus aurantiacus family 10 and a Sporotrichum thermophile family 11 endoxylanases. At 10 g l(-1) arabinoxylan, enzyme concentrations (KE values) needed to obtain half-maximal hydrolysis rates (V(max) values) were 4.4 nM for the xylanase from T. aurantiacus and 7.1 nM for the xylanase from S. thermophile. Determination of Vmax/KE revealed that the family 10 enzyme hydrolysed two times more efficiently WU-AX than the family 11 enzyme. Molecular weights of the products formed were assessed and separation of feruloyl-oligosaccharides was achieved by anion-exchange and size-exclusion chromatography (SEC). The main difference between the feruloylated products by xylanases of family 10 and 11 concerned the length of the products containing feruloyl-arabinosyl substitution. The xylanase from T. aurantiacus liberated from WU-AX a feruloyl arabinoxylodisaccharide (FAX2) as the shortest feruloylated fragment in contrast with the enzyme from S. thermophile, which liberated a feruloyl arabinoxylotrisaccharide (FAX3). These results indicated that different factors govern WU-AX breakdown by the two endoxylanases.

Crystal growth and analysis of ohmic contact and magneto-optical isolator properties of cadmium manganese telluride

NASA Astrophysics Data System (ADS)

Prakasam, Mythili; Viraphong, Oudomsack; Teulé-Gay, Lionel; Decourt, Rodolphe; Veber, Philippe; Víllora, Encarnación G.; Shimamura, Kiyoshi

2011-03-01

Cd1-xMnxTe (x=0.1, 0.3, 0.5, 0.7 and 0.9) (CMT) single crystals were grown by the vertical Bridgman method. The optical studies reveal that with the increase in Mn concentration, the band gap values increase, which is attributed to s, p-d exchange interaction between the band carriers and Mn ions. Faraday rotation angle of the grown CMT (x=0.5) crystals were measured at the following wavelengths: 825, 1060 and 1575 nm. It was inferred that CMT exhibit larger Faraday effect (3-6 times larger than terbium-gallium garnet (TGG) currently used for optical isolators) making it as an efficient material for optical isolator at longer wavelengths. Field-cooled and zero field-cooled magnetizations of CMT were measured as a function of temperature and magnetic field. The spin-glass like behavior of CMT and their tendency to decrease in magnitude with increasing Mn concentration have been analyzed. The metal contacts on the Cd1-xMnxTe (x=0.1, 0.5, 0.7 and 0.9) crystals have been made with various metals and metal alloys to establish the ohmic contact. The detector characteristics of CMT have been tested using γ-rays with 511 keV (22 Na) and 59.5 keV (241 Am).

The Invisible Made Visible: Using Impact Evaluations to Illuminate and Inform the Role of Knowledge Intermediaries

ERIC Educational Resources Information Center

Meagher, Laura; Lyall, Catherine

2013-01-01

Expectations for impacts from research create demand for effective knowledge exchange between academic and non-academic settings. This complex process may be facilitated by "knowledge intermediaries." Learning from evaluation can advance recognition of their diverse roles and enhance these interactive relationships connecting research,…

Knowledge Management in Sustainability Research Projects: Concepts, Effective Models, and Examples in a Multi-Stakeholder Environment

ERIC Educational Resources Information Center

Kaiser, David Brian; Köhler, Thomas; Weith, Thomas

2016-01-01

This article aims to sketch a conceptual design for an information and knowledge management system in sustainability research projects. The suitable frameworks to implement knowledge transfer models constitute social communities, because the mutual exchange and learning processes among all stakeholders promote key sustainable developments through…

Africa and China Higher Education Cooperation: Establishing Knowledge Sharing Partnership between Students

ERIC Educational Resources Information Center

Gonondo, Jean

2017-01-01

Knowledge sharing should not be confused neither with data sharing nor with information sharing; the knowledge sharing includes data and information sharing, skills and expertise communication, ideas exchange. Since the fourth FOCAC held in Egypt in 2009, many policies have been added to reinforce Africa and China educational cooperation,…

Partnerships for Knowledge Translation and Exchange in the Context of Continuing Professional Development

ERIC Educational Resources Information Center

Legare, France; Borduas, Francine; MacLeod, Tanya; Sketris, Ingrid; Campbell, Barbara; Jacques, Andre

2011-01-01

Continuing professional development (CPD) is an important vehicle for knowledge translation (KT); however, selecting CPD strategies that will impact health professionals' behavior and improve patient outcomes is complex. In response, we, KT researchers and CPD knowledge users, have recently formed a partnership known as the National Network for…

Indigenous Knowledge in Post-Secondary Educators' Practices: Nourishing the Learning Spirit

ERIC Educational Resources Information Center

Anuik, Jonathan; Gillies, Carmen L.

2012-01-01

From 2006 to 2009, Indigenous Elders and scholars shared their insights in the Comprehending and Nourishing the Learning Spirit Animation Theme Bundle of the Aboriginal Learning Knowledge Centre (ABLKC). The ABLKC was an applied research, knowledge exchange, and monitoring program with a mandate to advance Aboriginal education in Canada. One of…

Knowledge as a Resource--Networks Do Matter: A Study of SME Firms in Rural Illinois.

ERIC Educational Resources Information Center

Solymossy, Emeric

2000-01-01

Networks among people and businesses facilitate the capture and diffusion of technical and organizational knowledge and can be classified by type of knowledge being exchanged. Types include buyer-supplier information, technical problem-solving information, and informal community information. A survey of 141 small and medium-sized enterprises…

Simulation of energy spectrum of GEM detector from an x-ray quantum

NASA Astrophysics Data System (ADS)

Malinowski, K.; Chernyshova, M.; Czarski, T.; Kowalska-Strzęciwilk, E.; Linczuk, P.; Wojeński, A.; Krawczyk, R.; Gąska, M.

2018-01-01

This paper presents the results of the energy resolution simulation for the triple GEM-based detector for x-ray quantum of 5.9 keV . Photons of this energy are emitted by 55Fe source, which is a standard calibration marker for this type of detectors. The calculations were made in Garfield++ in two stages. In the first stage, the distribution of the amount of primary electrons generated in the drift volume by the x-ray quantum was simulated using the Heed program. Secondly, the primary electrons of the resulting quantitative distribution were treated as a source of electron avalanches propagated through the whole volume of the triple GEM-based detector. The distribution of the obtained signals created a spectrum corresponding to the peak at 5.9 keV, which allowed us to determine the theoretical energy resolution of the detector. Its knowledge allows observing and improving the eventual experimental deterioration of the energy resolution, inevitably accompanying processes of registration and processing of the signals.

The CROPROTECT project and wider opportunities to improve farm productivity through web-based knowledge exchange.

PubMed

Bruce, Toby J A

2016-05-01

A key global 21st century challenge is to maximize agricultural production while minimizing use of resources such as land, water, and energy to meet rising demand for produce. To meet this challenge, while also adapting to climate change, agriculture will have to become more knowledge intensive and deploy smarter farming techniques. The intention of this study was to: (1) Highlight the opportunity for web-based knowledge exchange to increase farm productivity and thus contribute to achieving food and energy security, (2) Give some examples of online farming information services such as the "CROPROTECT" tool I am developing in the UK, the CABI "Plantwise" Knowledge Bank and the IRRI "Rice Doctor," and (3) Consider lessons learnt so far. There are huge opportunities to facilitate knowledge exchange through online systems for farmers and people who advise farmers. CROPROTECT is interacting with users to determine priorities in terms of the pests, weeds, and diseases covered and is providing key information to assist with their management. Knowledge is a critical input for farming systems. Crop protection in particular is becoming more difficult due to evolution of pest resistance and changes in legislation. Up to date information can be made rapidly available and shared online through websites and smartphone Apps. Agricultural extension no longer relies solely on physical meetings and printed documents. The capacity to share information via the Internet is tremendous with its potential to reach a wide audience in the farming community, to provide rapid updates and to interact more with the users. However, in an era of information deluge, accessing relevant information and ensuring reliability are essential considerations. There is also a need to bring science and farming communities together to turn information into relevant farming knowledge.

Effect of the patient's knowledge on peritonitis rates in peritoneal dialysis.

PubMed

Sayed, Suheir A M; Abu-Aisha, Hasan; Ahmed, Magda E; Elamin, Sarra

2013-01-01

After a training period, patients maintained on continuous ambulatory peritoneal dialysis (CAPD) assume responsibility for their own treatment. With the aid of appropriate tools, home visits help with ongoing evaluation and training for these patients. We conducted a home visit survey of 50 patients maintained on CAPD in Sudan between April 2009 and June 2010. Housing conditions, home environment, and patient's or caregiver's knowledge about peritoneal dialysis and the exchange procedure were evaluated using structured data collection sheets. Scores were compared with infection rates in the patients before the home visit. Patients were maintained on CAPD for a median duration of 11 months. Their mean age was 42 ± 23 years; 70% were male; and 14% had diabetes. Only 34% of patients had suitable housing conditions, and 56% required assisted PD. Of the autonomous patients and assisting family members, 11.6% were illiterate. The median achieved knowledge score was 11.5 of 35 points. The median achieved exchange score was 15 of 20 points. Knowledge and exchange scores were positively and significantly correlated (R = 0.5, p = 0.00). More patients in the upper quartile than in the middle and lower quartiles of knowledge scores were adherent to daily exit-site care (33.3% vs 5.3%, p = 0.02). Compared with patients in the middle and lower quartiles of knowledge score, patients in the upper quartile had lower rates of peritonitis, exit-site infection, and hospitalization. The proposed evaluation form is a valid and reliable assessment tool for the follow-up of CAPD patients. Patients in the upper quartile of knowledge score demonstrated better adherence to the recommended treatment protocols and lower infection rates.

Bipolar disorder research 2.0: Web technologies for research capacity and knowledge translation.

PubMed

Michalak, Erin E; McBride, Sally; Barnes, Steven J; Wood, Chanel S; Khatri, Nasreen; Balram Elliott, Nusha; Parikh, Sagar V

2017-12-01

Current Web technologies offer bipolar disorder (BD) researchers many untapped opportunities for conducting research and for promoting knowledge exchange. In the present paper, we document our experiences with a variety of Web 2.0 technologies in the context of an international BD research network: The Collaborative RESearch Team to Study psychosocial issues in BD (CREST.BD). Three technologies were used as tools for enabling research within CREST.BD and for encouraging the dissemination of the results of our research: (1) the crestbd.ca website, (2) social networking tools (ie, Facebook, Twitter), and (3) several sorts of file sharing (ie YouTube, FileShare). For each Web technology, we collected quantitative assessments of their effectiveness (in reach, exposure, and engagement) over a 6-year timeframe (2010-2016). In general, many of our strategies were deemed successful for promoting knowledge exchange and other network goals. We discuss how we applied our Web analytics to inform adaptations and refinements of our Web 2.0 platforms to maximise knowledge exchange with people with BD, their supporters, and health care providers. We conclude with some general recommendations for other mental health researchers and research networks interested in pursuing Web 2.0 strategies. © 2017 John Wiley & Sons, Ltd.

Possible Charge-Exchange X-Ray Emission in the Cygnus Loop Detected with Suzaku

NASA Technical Reports Server (NTRS)

Katsuda, Satoru; Tsunemi, Hiroshi; Mori, Koji; Uchida, Hiroyuki; Kosugi, Hiroko; Kimura, Masashi; Nakajima, Hiroshi; Takakura, Satoru; Petre, Robert; Hewitt. John W.;

14 CFR 61.27 - Voluntary surrender or exchange of certificate.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Voluntary surrender or exchange of certificate. 61.27 Section 61.27 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... my own reasons, with full knowledge that my (insert name of certificate or rating, as appropriate...

14 CFR 61.27 - Voluntary surrender or exchange of certificate.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Voluntary surrender or exchange of certificate. 61.27 Section 61.27 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... my own reasons, with full knowledge that my (insert name of certificate or rating, as appropriate...

Politeness Strategies in Collaborative E-Mail Exchanges

ERIC Educational Resources Information Center

Vinagre, Margarita

2008-01-01

Computer-supported collaborative learning (CSCL) has been the subject of a wide range of studies over the last twenty years. Previous research suggests that CSCL exchanges can facilitate group-based learning and knowledge construction among learners who are in different geographical locations [Littleton, K. & Whitelock, D. (2004). "Guiding the…

[Open circuit: the exchange of medical and scientific knowledge in Latin American in the early 20th century].

PubMed

Almeida, Marta de

2006-01-01

This article discusses the Latin American Medical Congresses and International Exhibitions on Hygiene held in the first few decades of the 20th century as a strategy for underpinning and influencing medical knowledge within the specialized community itself and for public authorities, which were fundamental for presenting to society at large as they were seen as the vehicles of official know-how on the art of medicating. These events made up part of a broader movement to internationalize and coordinate the professional field of medicine in Latin America. The article further suggests that the activities that took place during these events played a key role in the propagation of ideas and exchange of experience between Latin American nations, forming a network of scientific exchange in the continent.

Tear exchange and contact lenses: A review

PubMed Central

Muntz, Alex; Subbaraman, Lakshman N.; Sorbara, Luigina; Jones, Lyndon

2015-01-01

Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses. PMID:25575892

Marginalia, commonplaces, and correspondence: scribal exchange in early modern science.

PubMed

Yale, Elizabeth

2011-06-01

In recent years, historians of science have increasingly turned their attention to the "print culture" of early modern science. These studies have revealed that printing, as both a technology and a social and economic system, structured the forms and meanings of natural knowledge. Yet in early modern Europe, naturalists, including John Aubrey, John Evelyn, and John Ray, whose work is discussed in this paper, often shared and read scientific texts in manuscript either before or in lieu of printing. Scribal exchange, exemplified in the circulation of writings like commonplace books, marginalia, manuscript treatises, and correspondence, was the primary means by which communities of naturalists constructed scientific knowledge. Print and manuscript were necessary partners. Manuscript fostered close collaboration, and could be circulated relatively cheaply; but, unlike print, it could not reliably secure priority or survival for posterity. Naturalists approached scribal and print communication strategically, choosing the medium that best suited their goals at any given moment. As a result, print and scribal modes of disseminating information, constructing natural knowledge, and organizing communities developed in tandem. Practices typically associated with print culture manifested themselves in scribal texts and exchanges, and vice versa. "Print culture" cannot be hived off from "scribal culture." Rather, in their daily jottings and exchanges, naturalists inhabited, and produced, one common culture of communication. Copyright © 2010 Elsevier Ltd. All rights reserved.

Microdosimetric investigation of a fast neutron radiobiology facility utilising the d(4)-9Be reaction.

PubMed

Waker, A J; Maughan, R L

1986-11-01

For fast neutron therapy and radiobiology beams, knowledge of the primary neutron spectrum is the most fundamental requirement for the definition of radiation quality. However, microdosimetric measurements in the form of single-event spectra not only complement the primary neutron spectrum as a statement of radiation quality but also provide a sensitive method of detecting changes in the radiation field in situations where it is no longer possible to have precise knowledge of the primary neutron spectrum, for example after collimator changes and in positions where the radiation field consists of a large scattered component. For the various collimator arrangements employed at the Gray Laboratory facility small perturbations of the radiation field are observed which can be related to a softening of the primary neutron spectrum with increasing field size of the collimator. Gamma fraction determinations are in very good agreement with measurements employing the dual chamber technique and also show small changes with collimator field size giving rise to gamma components ranging from 0.09 to 0.12, the higher values being measured for the larger field sizes. Quality changes represented by the shape of the measured event-size spectra and the derived microdosimetric parameters were greatest for off axis and phantom measurements. With increasing depth in water, yD was found to decrease from 47.3 keV micron-1 at 5 cm to 35.6 keV micron-1 at 15 cm depth, and the gamma fraction was found to increase from 0.23 to 0.40. Although there is no generally accepted and agreed method of relating microdosimetric information to biological effectiveness, the dual radiation theory in its original form (Kellerer and Rossi 1972) has been shown to be a very useful model for the assessment of the biological effectiveness of fast neutrons (Kellerer et al 1976). The microdosimetric parameter which is used in the dual radiation model is the dose mean specific energy corrected for saturation zeta* which, for a 2 micron simulated diameter, is related to the dose mean lineal energy corrected for saturation y* by zeta* = y* keV micron-1 X 0.51 X 10(-2) Gy. Values of y* determined for each of the collimator arrangements used at the Gray Laboratory show a spread of some 6% (table 1) and, as the dose fraction between lineal energies 5 and 150 keV micron-1 (the recoil proton component) do not alter by more than 3%, radiobiological experiments performed with different collimator arrangements would show no observable differences.(ABSTRACT TRUNCATED AT 400 WORDS)

A Canonical Correlation Analysis of Social Capital and Knowledge Exchange for Virtual Members of IT Teams

ERIC Educational Resources Information Center

Dutton Feliu, Genevieve

2018-01-01

Social capital theory conceptualized social capital as key to connecting team members into the flow of valued resources and activities, with knowledge deemed one of the most valuable of these resources. Yet, the literature found teams struggle to effectively share knowledge. This quantitative survey-based study assessed the interrelationship…

Exploring Knowledge Exchange between Senior and Future Leaders: A Grounded-Theory Study

ERIC Educational Resources Information Center

Gonzaga, Stephanie Young

2009-01-01

A grounded theory study examined senior leaders methods of knowledge sharing with junior leaders in a small commercial mortgage company. The study was designed to develop an emergent theory to explain the cultural elements that influenced the methods leaders used to transfer knowledge to junior people. The study identified a systemic value of…

Navigating complexity through knowledge coproduction: Mainstreaming ecosystem services into disaster risk reduction.

PubMed

Reyers, Belinda; Nel, Jeanne L; O'Farrell, Patrick J; Sitas, Nadia; Nel, Deon C

2015-06-16

Achieving the policy and practice shifts needed to secure ecosystem services is hampered by the inherent complexities of ecosystem services and their management. Methods for the participatory production and exchange of knowledge offer an avenue to navigate this complexity together with the beneficiaries and managers of ecosystem services. We develop and apply a knowledge coproduction approach based on social-ecological systems research and assess its utility in generating shared knowledge and action for ecosystem services. The approach was piloted in South Africa across four case studies aimed at reducing the risk of disasters associated with floods, wildfires, storm waves, and droughts. Different configurations of stakeholders (knowledge brokers, assessment teams, implementers, and bridging agents) were involved in collaboratively designing each study, generating and exchanging knowledge, and planning for implementation. The approach proved useful in the development of shared knowledge on the sizable contribution of ecosystem services to disaster risk reduction. This knowledge was used by stakeholders to design and implement several actions to enhance ecosystem services, including new investments in ecosystem restoration, institutional changes in the private and public sector, and innovative partnerships of science, practice, and policy. By bringing together multiple disciplines, sectors, and stakeholders to jointly produce the knowledge needed to understand and manage a complex system, knowledge coproduction approaches offer an effective avenue for the improved integration of ecosystem services into decision making.

Navigating complexity through knowledge coproduction: Mainstreaming ecosystem services into disaster risk reduction

PubMed Central

Reyers, Belinda; Nel, Jeanne L.; O’Farrell, Patrick J.; Sitas, Nadia; Nel, Deon C.

2015-01-01

Achieving the policy and practice shifts needed to secure ecosystem services is hampered by the inherent complexities of ecosystem services and their management. Methods for the participatory production and exchange of knowledge offer an avenue to navigate this complexity together with the beneficiaries and managers of ecosystem services. We develop and apply a knowledge coproduction approach based on social–ecological systems research and assess its utility in generating shared knowledge and action for ecosystem services. The approach was piloted in South Africa across four case studies aimed at reducing the risk of disasters associated with floods, wildfires, storm waves, and droughts. Different configurations of stakeholders (knowledge brokers, assessment teams, implementers, and bridging agents) were involved in collaboratively designing each study, generating and exchanging knowledge, and planning for implementation. The approach proved useful in the development of shared knowledge on the sizable contribution of ecosystem services to disaster risk reduction. This knowledge was used by stakeholders to design and implement several actions to enhance ecosystem services, including new investments in ecosystem restoration, institutional changes in the private and public sector, and innovative partnerships of science, practice, and policy. By bringing together multiple disciplines, sectors, and stakeholders to jointly produce the knowledge needed to understand and manage a complex system, knowledge coproduction approaches offer an effective avenue for the improved integration of ecosystem services into decision making. PMID:26082541

22 CFR 62.30 - Camp counselors.

Code of Federal Regulations, 2010 CFR

2010-04-01

... programs promote international understanding by improving American knowledge of foreign cultures while enabling foreign participants to increase their knowledge of American culture. The foreign participants are... previously participated in a camp counselor exchange. (j) In order to ensure that as many different...

Overview of the negative ion based neutral beam injectors for ITER.

PubMed

Schunke, B; Boilson, D; Chareyre, J; Choi, C-H; Decamps, H; El-Ouazzani, A; Geli, F; Graceffa, J; Hemsworth, R; Kushwah, M; Roux, K; Shah, D; Singh, M; Svensson, L; Urbani, M

2016-02-01

The ITER baseline foresees 2 Heating Neutral Beams (HNB's) based on 1 MeV 40 A D(-) negative ion accelerators, each capable of delivering 16.7 MW of deuterium atoms to the DT plasma, with an optional 3rd HNB injector foreseen as a possible upgrade. In addition, a dedicated diagnostic neutral beam will be injecting ≈22 A of H(0) at 100 keV as the probe beam for charge exchange recombination spectroscopy. The integration of the injectors into the ITER plant is nearly finished necessitating only refinements. A large number of components have passed the final design stage, manufacturing has started, and the essential test beds-for the prototype route chosen-will soon be ready to start.

R(K(*)) from dark matter exchange

NASA Astrophysics Data System (ADS)

Cline, James M.; Cornell, Jonathan M.

2018-07-01

Hints of lepton flavor violation have been observed by LHCb in the rate of the decay B → Kμ+μ- relative to that of B → Ke+e-. This can be explained by new scalars and fermions which couple to standard model particles and contribute to these processes at loop level. We explore a simple model of this kind, in which one of the new fermions is a dark matter candidate, while the other is a heavy vector-like quark and the scalar is an inert Higgs doublet. We explore the constraints on this model from flavor observables, dark matter direct detection, and LHC run II searches, and find that, while currently viable, this scenario will be directly tested by future experiments.

Wide-view charge exchange recombination spectroscopy diagnostic for Alcator C-Mod.

PubMed

Rowan, W L; Bespamyatnov, I O; Granetz, R S

2008-10-01

This diagnostic measures temperature, density, and rotation for the fully stripped boron ion between the pedestal top and the plasma core with resolution consistent with the profile gradients. The diagnostic neutral beam used for the measurements generates a 50 keV, 6 A hydrogen beam. The optical systems provide views in both poloidal and toroidal directions. The imaging spectrometer is optimized to simultaneously accept 45 views as input with minimum cross-talk. In situ calibration techniques are applied for spatial location, spectral intensity, and wavelength. In the analysis, measured spectra are fitted to a model constructed from a detailed description of the emission physics. Methods for removal of interfering spectra are included. Applications include impurity and thermal transport.

Effects of large-angle Coulomb collisions on inertial confinement fusion plasmas.

PubMed

Turrell, A E; Sherlock, M; Rose, S J

2014-06-20

Large-angle Coulomb collisions affect the rates of energy and momentum exchange in a plasma, and it is expected that their effects will be important in many plasmas of current research interest, including in inertial confinement fusion. Their inclusion is a long-standing problem, and the first fully self-consistent method for calculating their effects is presented. This method is applied to "burn" in the hot fuel in inertial confinement fusion capsules and finds that the yield increases due to an increase in the rate of temperature equilibration between electrons and ions which is not predicted by small-angle collision theories. The equilibration rate increases are 50%-100% for number densities of 10(30)  m(-3) and temperatures around 1 keV.

Determining the Exchangeability of Concept Map and Problem-Solving Essay Scores

ERIC Educational Resources Information Center

Hollenbeck, Keith; Twyman, Todd; Tindal, Gerald

2006-01-01

This study investigated the score exchangeability of concept maps with problem-solving essays. Of interest was whether sixth-grade students' concept maps predicted their scores on essay responses that used concept map content. Concept maps were hypothesized to be alternatives to performance assessments for content-area domain knowledge in science.…

Extroversion Personality, Domain Knowledge, and the Creativity of New Product Development Engineers

ERIC Educational Resources Information Center

Chiang, Yun-Hwa; Hsu, Chu-Chun; Shih, Hsi-An

2017-01-01

Creativity refers to a person's thinking of new and useful ideas at work. Drawing on the personality literature, this study proposes that employees with high extroversion personality will exchange job relevant information with colleagues to generate creativity. Drawing on the information exchange theory, this study further proposes that the effect…

Global Education: Educating for Our Common Future.

ERIC Educational Resources Information Center

Randall, Ruth E.

Minnesota plays an integral role in the worldwide increase in the exchange of goods, services, and ideas. It is imperative that the state's citizens be able to relate to an increasingly interrelated world and to gain the skills, attitudes, and knowledge needed to participate intelligently in such exchanges. Educating to these ends is essential.…

Sterilization of foods with low-energy electrons (``soft-electrons'')

NASA Astrophysics Data System (ADS)

Hayashi, Toru; Takahashi, Yoko; Todoriki, Setsuko

1998-06-01

Electrons with an energy of 300 keV or lower were defined as "Soft-electrons", which showed several advantages over conventional irradiation with gamma-rays or high-energy electrons in decontamination of grains and spices. Energies of electrons necessary to reduce microbial loads to levels lower than 10 CFU/g were 60 keV for brown rice, 75 keV for wheat, 100 keV for white pepper, coriander and basil, 130 keV for buckwheat, 160 keV for rough rice, and 210 keV for black pepper. Electrons with such energies did not significantly influence the quality.

It's hard to play ball: A qualitative study of knowledge exchange and silo effects in public health.

PubMed

Johnson, Rebecca; Grove, Amy; Clarke, Aileen

2018-01-02

Partnerships in public health form an important component of commissioning and implementing services, in England and internationally. In this research, we examine the views of staff involved in a City-wide health improvement programme which ran from 2009 to 2013 in England. We examine the practicalities of partnership work in community settings, and we describe some of barriers faced when implementing a large, multi-organisation health improvement programme. Qualitative, semi-structured interviews were performed. Purposive sampling was used to identify potential participants in the programme: programme board of directors, programme and project managers and intervention managers. Interviews were conducted one-to-one. We conducted a thematic analysis using the 'one sheet of paper' technique. This involved analysing data deductively, moving from initial to axial coding, developing categories and then identifying emerging themes. Fifteen interviews were completed. Three themes were identified. The first theme reflects how poor communication approaches hindered the ability of partnerships to deliver their aims and objectives in a range of ways and for a range of reasons. Our second theme reflects how a lack of appropriate knowledge exchange hindered decision-making, affected trust and contributed to protectionist approaches to working. This lack of shared, and communicated, understanding of what type of knowledge is most appropriate and in which circumstance made meaningful knowledge exchange challenging for decision-making and partnership-working in the City-wide health improvement programme. Theme three demonstrates how perceptions about silos in partnership-working could be problematic, but silos themselves were at times beneficial to partnerships. This revealed a mismatch between rhetoric and a realistic understanding of what components of the programme were functional and which were more hindrance than help. There were high expectations placed on the concept of what partnership work was, or how it should be done. We found our themes to be interdependent, and reflective of the 'dynamic fluid process' discussed within the knowledge mobilisation literature. We contend that reframing normal and embedded processes of silos and silo-working already in use might ease resistance to some knowledge exchange processes and contribute to better long-term functioning of public health partnerships.

Medical encounters and exchange in early Canadian missions.

PubMed

Parsons, Chris

2008-01-01

The exchange of medical and pharmaceutical knowledge was an important facet of the encounter between native and newcomer in early Canada. Throughout New France Récollet and Jesuit missionaries were given privileged access both to indigenous peoples and indigenous plants. Curiously, however, when it came to describing medical treatments, it was people, rather than medicinal plants, that were targets of what might be called "the descriptive enterprise." Attempting to divide suspect shamanic remedies from those deemed natural, missionary observers carefully documented the context of medical treatments rather than simply the specific remedy applied for treatment. Using records left by early Canadian missionaries this paper will look at the peculiar character of medical exchange in the missions of seventeenth and eighteenth-century New France to look at the interpersonal encounters that formed a constitutive element of colonial botany and framed the way in which indigenous knowledge was represented to metropolitan audiences.

Community Data Management and the Exchange for Local Observations and Knowledge of the Arctic

NASA Astrophysics Data System (ADS)

Duerr, R.; Pulsifer, P. L.; Strawhacker, C.; Mccann, H. S.

2016-12-01

The mission of the Exchange for Local Observations and Knowledge of the Arctic (ELOKA) is to facilitate the collection, preservation, exchange, and use of local observations and knowledge by Indigenous communities in the Arctic by providing data management services and user support, and by fostering collaboration between resident Arctic experts and visiting researchers. ELOKA's overarching philosophy is that Local and Traditional Knowledge (LTK) and scientific data and expertise are complementary and reinforcing ways of understanding the Arctic system. Collecting, documenting, preserving, and sharing knowledge is a cooperative endeavor, and ELOKA is dedicated to fostering ethical knowledge sharing among Arctic residents and communities, scientists, educators, policy makers, and the general public. But what does that mean in practice and what are the next steps for ELOKA in the coming years? In this presentation, we discuss the ethical issues involved with data management for LTK and community-based projects, some of the tools ELOKA has developed for interacting with communities and researchers and for managing LTK data, and our plans for the future. These include a discussion of the considerations local and community-based projects should make when planning and conducting research. It is clear, for example, that research projects should either include Indigenous voices at the outset of the project or have a prominent Indigenous voice so that appropriate methods or approaches can be adopted. Discussion of data access and funder obligations will be included. The data management tools that ELOKA employs and is developing for the future that can manage the wide range of data types typical of a community or LTK project will also be described, as will ELOKA's program for transferring long-term data management skills to communities that wish to take that on. Finally, ELOKA's plans for the future will be described.

Exchange of Standardized Flight Dynamics Data

NASA Technical Reports Server (NTRS)

Martin-Mur, Tomas J.; Berry, David; Flores-Amaya, Felipe; Folliard, J.; Kiehling, R.; Ogawa, M.; Pallaschke, S.

2004-01-01

Spacecraft operations require the knowledge of the vehicle trajectory and attitude and also that of other spacecraft or natural bodies. This knowledge is normally provided by the Flight Dynamics teams of the different space organizations and, as very often spacecraft operations involve more than one organization, this information needs to be exchanged between Agencies. This is why the Navigation Working Group within the CCSDS (Consultative Committee for Space Data Systems), has been instituted with the task of establishing standards for the exchange of Flight Dynamics data. This exchange encompasses trajectory data, attitude data, and tracking data. The Navigation Working Group includes regular members and observers representing the participating Space Agencies. Currently the group includes representatives from CNES, DLR, ESA, NASA and JAXA. This Working Group meets twice per year in order to devise standardized language, methods, and formats for the description and exchange of Navigation data. Early versions of some of these standards have been used to support mutual tracking of ESA and NASA interplanetary spacecraft, especially during the arrival of the 2003 missions to Mars. This paper provides a summary of the activities carried out by the group, briefly outlines the current and envisioned standards, describes the tests and operational activities that have been performed using the standards, and lists and discusses the lessons learned from these activities.

Partnerships for knowledge translation and exchange in the context of continuing professional development.

PubMed

Légaré, France; Borduas, Francine; MacLeod, Tanya; Sketris, Ingrid; Campbell, Barbara; Jacques, André

2011-01-01

Continuing professional development (CPD) is an important vehicle for knowledge translation (KT); however, selecting CPD strategies that will impact health professionals' behavior and improve patient outcomes is complex. In response, we, KT researchers and CPD knowledge users, have recently formed a partnership known as the National Network for Patient-Centered Evidence-Based Continuing Professional Development. The partnership was initiated in 2006 with a series of CIHR Knowledge Translation: Planning, Meetings and Dissemination grants. The objectives of these grants were to bring members of the CPD and KT communities together, determine their interest in working together, identify similarities and differences in the fields of CPD and KT, and develop working groups to inform larger collaborative initiatives to support knowledge translation and exchange. The vision for this partnership is to become a premiere knowledge translation collaboration and a cutting-edge implementation network that informs the provision of CPD across Canada and abroad. This paper reports on the development and outcomes of this network to date. Copyright © 2010 The Alliance for Continuing Medical Education, the Society for Academic Continuing Medical Education, and the Council on CME, Association for Hospital Medical Education.

A Statistical Study of Spatial Variation of Relativistic Electron Precipitation Energy Spectra With Polar Operational Environmental Satellites

NASA Astrophysics Data System (ADS)

Shekhar, S.; Millan, R. M.; Hudson, M. K.

2018-05-01

The mechanisms that drive relativistic electron precipitation (REP) from the radiation belts can be better understood with a better knowledge of the particle energies involved. National Oceanic and Atmospheric Administration Polar Operational Environmental Satellites, being a network of multiple satellites, can provide multiple point spectral data over a long time period, including the Van Allen Probe's era. The number of energy channels is limited, but the particle detectors on Polar Operational Environmental Satellites have a narrow field of view allowing an investigation of bounce loss cone particles. We use the ratio of count rates in the E3 (>300 keV) and the P6 (>700 keV) channels as a parameter to define spectral hardness. Using this parameter, the spatial variation of spectral hardness of REP events was investigated. It was found that very soft events were mostly found in the dusk-midnight-early morning magnetic local time sectors and L˜ 5-7 while the hardest events were located in the postnoon sector peaking at L˜ 4-5. The hardest events peaked at lower L shells, and less than 20% were coincident with low-energy (30-80 keV) proton precipitation. Further, around 70% of nightside REP coincident with proton precipitation was associated with stretched magnetic field lines indicating that curvature scattering may have been an important driver. Around 62% of nightside REP coincident with proton precipitation associated with relaxed magnetic field lines, suggesting a mechanism other than magnetic field curvature scattering, was highly energetic.

Tuberculosis knowledge among injecting drug users visiting syringe exchange programme in Tallinn, Estonia.

PubMed

Rüütel, Kristi; Parker, R David; Sobolev, Igor; Loit, Helle-Mai

2012-12-01

The purpose of the current study was to describe tuberculosis (TB) knowledge, beliefs, and experience with TB services among injecting drug users. Participants for this anonymous, cross-sectional study were recruited from a community based syringe exchange programme in Tallinn, Estonia. A structured questionnaire was completed and included information on socio-demographics, health history, drug use, and knowledge about TB and HIV. The study included 407 people (79% male, mean age 27.9 years, mean injection drug use 9.4 years). 32.9% of participants reported HIV infection and 1.7% lifetime history of TB. 26.4% participants (n=106) reported symptoms suggestive of TB. 93% of participants recognized correctly that TB is air-borne infection and 91% that HIV is a risk factor for TB. Only 40% of the participants knew that TB diagnostics and treatment in Estonia are free of charge for everybody and 58% reported they knew where to get health care services in case they suspected that they had TB. TB transmission and treatment adherence knowledge was better among those in contact with either health care or harm reduction services, e.g the community based syringe exchange programme. Similar to HIV services, TB prevention and education should be integrated into harm reduction and drug treatment programmes to facilitate early diagnosis and treatment of TB among injecting drug users.

Investigation of Energy Release in Microflares Observed by the Second Sounding Rocket Flight of the Focusing Optics X-ray Solar Imager (FOXSI-2)

NASA Astrophysics Data System (ADS)

Vievering, J. T.; Glesener, L.; Panchapakesan, S. A.; Ryan, D.; Krucker, S.; Christe, S.; Buitrago-Casas, J. C.; Inglis, A. R.; Musset, S.

2017-12-01

Observations of the Sun in hard x-rays can provide insight into many solar phenomena which are not currently well-understood, including the mechanisms behind particle acceleration in flares. RHESSI is the only solar-dedicated imager currently operating in the hard x-ray regime. Though RHESSI has greatly added to our knowledge of flare particle acceleration, the indirect imaging method of rotating collimating optics is fundamentally limited in sensitivity and dynamic range. By instead using a direct imaging technique, the structure and evolution of even small flares and active regions can be investigated in greater depth. FOXSI (Focusing Optics X-ray Solar Imager), a hard x-ray instrument flown on two sounding rocket campaigns, seeks to achieve these improved capabilities by using focusing optics for solar observations in the 4-20 keV range. During the second of the FOXSI flights, flown on December 11, 2014, two microflares were observed, estimated as GOES class A0.5 and A2.5 (upper limits). Here we present current imaging and spectral analyses of these microflares, exploring the nature of energy release and comparing to observations from other instruments. Additionally, we feature the first analysis of data from the FOXSI-2 CdTe strip detectors, which provide improved efficiency above 10 keV. Through this analysis, we investigate the capabilities of FOXSI in enhancing our knowledge of smaller-scale solar events.

THE ADVERSE OUTCOME PATHWAY (AOP) FRAMEWORK ...

EPA Pesticide Factsheets

An Adverse Outcome Pathway (AOP) represents the organization of current and newly acquired knowledge of biological pathways. These pathways contain a series of nodes (Key Events, KEs) that when sufficiently altered influence the next node on the pathway, beginning from an Molecular Initiating Event (MIE), through intermediate KEs, ending in an Adverse Outcome (AO) which may be used as a basis for decision making. A KE is a measurable biological change, and is linked with other KEs via Key Event Relationships (KERs). A given KE may be involved in several AOPs, leading to a plausible network of biological changes that are involved in an organism’s response to an external stressor. When describing an AOP, five guiding principles have been proposed [1]: 1) an AOP is not specific to a single external stressor, 2) AOPs are modular, with KEs and KERs that can be used in several AOPs, 3) a single AOP is the unit of development, 4) most biological responses will be the result of networks of AOPs, and 5) AOPs will be modified as more biological knowledge becomes available. The collaborative development of AOPs is recommended to be performed using the AOP-Wiki (https://aopwiki.org), which is an effort between the European Commission – DG Joint Research Centre (JRC) and U.S. Environmental Protection Agency (EPA). The Wiki is one part of a larger OECD-sponsored AOP Knowledgebase effort, which is a repository for all AOPs developed as part of the Organization for Economic

Higher Education Exchange 1997.

ERIC Educational Resources Information Center

Brown, David W., Ed.

A foreword and 11 articles discuss the nature and structure of public scholarship. The contents include: "Foreword" (Deborah Witte); (1) "Public Scholarship: The Dissemination of Knowledge" (Jean Cameron) which maintains the public has claims on higher education as a creator and disseminator of knowledge; (2) "Daring to Be…

Online Peer-to-Peer Communities in the Daily Lives of People With Chronic Illness: A Qualitative Systematic Review.

PubMed

Kingod, Natasja; Cleal, Bryan; Wahlberg, Ayo; Husted, Gitte R

2017-01-01

This qualitative systematic review investigated how individuals with chronic illness experience online peer-to-peer support and how their experiences influence daily life with illness. Selected studies were appraised by quality criteria focused upon research questions and study design, participant selection, methods of data collection, and methods of analysis. Four themes were identified: (a) illness-associated identity work, (b) social support and connectivity, (c) experiential knowledge sharing, and (d) collective voice and mobilization. Findings indicate that online peer-to-peer communities provide a supportive space for daily self-care related to chronic illness. Online communities provided a valued space to strengthen social ties and exchange knowledge that supported offline ties and patient-doctor relationships. Individuals used online communities to exchange experiential knowledge about everyday life with illness. This type of knowledge was perceived as extending far beyond medical care. Online communities were also used to mobilize and raise collective awareness about illness-specific concerns. © The Author(s) 2016.

Interdisciplinary knowledge exchange across scales in a globally changing marine environment.

PubMed

McDonald, Karlie S; Hobday, Alistair J; Fulton, Elizabeth A; Thompson, Peter A

2018-07-01

The effects of anthropogenic global environmental change on biotic and abiotic processes have been reported in aquatic systems across the world. Complex synergies between concurrent environmental stressors and the resilience of the system to regime shifts, which vary in space and time, determine the capacity for marine systems to maintain structure and function with global environmental change. Consequently, an interdisciplinary approach that facilitates the development of new methods for the exchange of knowledge between scientists across multiple scales is required to effectively understand, quantify and predict climate impacts on marine ecosystem services. We use a literature review to assess the limitations and assumptions of current pathways to exchange interdisciplinary knowledge and the transferability of research findings across spatial and temporal scales and levels of biological organization to advance scientific understanding of global environmental change in marine systems. We found that species-specific regional scale climate change research is most commonly published, and "supporting" is the ecosystem service most commonly referred to in publications. In addition, our paper outlines a trajectory for the future development of integrated climate change science for sustaining marine ecosystem services such as investment in interdisciplinary education and connectivity between disciplines. © 2018 John Wiley & Sons Ltd.

Yet another UFO in the X-ray spectrum of a high-z lensed QSO

NASA Astrophysics Data System (ADS)

Dadina, M.; Vignali, C.; Cappi, M.; Lanzuisi, G.; Ponti, G.; Torresi, E.; De Marco, B.; Chartas, G.; Giustini, M.

2018-02-01

Aim. Ultra-fast outflows (UFO) appear to be common in local active galactic nuclei (AGN) and may be powerful enough (Ėkin ≥ 1% of Lbol) to effectively quench the star formation in their host galaxies. To test feedback models based on AGN outflows, it is mandatory to investigate UFOs near the peak of AGN activity, that is, at high-z where only a few studies are available to date. Methods: UFOs produce Fe resonant absorption lines measured above ≈7 keV. The most critical problem in detecting such features in distant objects is the difficulty in obtaining X-ray data with sufficient signal-to-noise. We therefore selected a distant QSO that gravitational lensing made bright enough for these purposes, the z = 2.64 QSO MG J0414+0534, and observed it with XMM-Newton for ≈78 ks. Results: The X-ray spectrum of MG J0414+0534 is complex and shows signatures of cold absorption (NH ≈ 4 × 1022 cm-2) and of the presence of an iron emission line (E ≈ 6.4 keV, EW = 95 ± 53 eV) consistent with it originating in the cold absorber. Our main result, however, is the robust detection (more than 5σ) of an absorption line at Eint ≈ 9.2 keV (Eobs ≈ 2.5 keV observer frame). If interpreted as due to FeXXVI, it implies gas outflowing at vout ≈ 0.3c. To our knowledge, this is the first detection of an UFO in a radio-loud quasar at z ≥ 1.5. We estimated that the UFO mechanical output is Ėkin ≈ 2.5Lbol with ṗout/ṗrad ≈ 17 indicating that it is capable of installing significant feedback between the super-massive black hole and the bulge of the host galaxy. We argue that this also suggests a magnetic driving origin of the UFO.

Benefits of negative social exchanges for emotional closeness.

PubMed

Fung, Helene H; Yeung, Dannii Y; Li, Kin-Kit; Lang, Frieder R

2009-09-01

Negative exchanges in social relationships have traditionally been studied as having negative consequences. This study explored whether they might have positive effects for relationship closeness. The sample included 351 adults, aged between 18 and 91 years, residing in Hong Kong, China. Closeness of social partners to the participants was measured by the Social Convoy Questionnaire, and the levels of negative exchanges and social support from each social partner were assessed. Multilevel analyses revealed that more negative exchanges were associated with a more positive change in closeness over a 2-year period, even after statistically controlling for social support and sociostructural characteristics of the participant and the social partner. Findings extended our knowledge on the positive effects of negative exchanges and their moderating conditions.

Towards integration of clinical decision support in commercial hospital information systems using distributed, reusable software and knowledge components.

PubMed

Müller, M L; Ganslandt, T; Eich, H P; Lang, K; Ohmann, C; Prokosch, H U

2001-12-01

Clinicians' acceptance of clinical decision support depends on its workflow-oriented, context-sensitive accessibility and availability at the point of care, integrated into the Electronic Patient Record (EPR). Commercially available Hospital Information Systems (HIS) often focus on administrative tasks and mostly do not provide additional knowledge based functionality. Their traditionally monolithic and closed software architecture encumbers integration of and interaction with external software modules. Our aim was to develop methods and interfaces to integrate knowledge sources into two different commercial hospital information systems to provide the best decision support possible within the context of available patient data. An existing, proven standalone scoring system for acute abdominal pain was supplemented by a communication interface. In both HIS we defined data entry forms and developed individual and reusable mechanisms for data exchange with external software modules. We designed an additional knowledge support frontend which controls data exchange between HIS and the knowledge modules. Finally, we added guidelines and algorithms to the knowledge library. Despite some major drawbacks which resulted mainly from the HIS' closed software architectures we showed exemplary, how external knowledge support can be integrated almost seamlessly into different commercial HIS. This paper describes the prototypical design and current implementation and discusses our experiences.

Guest Molecule Exchange Kinetics for the 2012 Ignik Sikumi Gas Hydrate Field Trial

DOE Office of Scientific and Technical Information (OSTI.GOV)

White, Mark D.; Lee, Won Suk

A commercially viable technology for producing methane from natural gas hydrate reservoirs remains elusive. Short-term depressurization field tests have demonstrated the potential for producing natural gas via dissociation of the clathrate structure, but the long-term performance of the depressurization technology ultimately requires a heat source to sustain the dissociation. A decade of laboratory experiments and theoretical studies have demonstrated the exchange of pure CO2 and N2-CO2 mixtures with CH4 in sI gas hydrates, yielding critical information about molecular mechanisms, recoveries, and exchange kinetics. Findings indicated the potential for producing natural gas with little to no production of water and rapidmore » exchange kinetics, generating sufficient interest in the guest-molecule exchange technology for a field test. In 2012 the U.S. DOE/NETL, ConocoPhillips Company, and Japan Oil, Gas and Metals National Corporation jointly sponsored the first field trial of injecting a mixture of N2-CO2 into a CH4-hydrate bearing formation beneath the permafrost on the Alaska North Slope. Known as the Ignik Sikumi #1 Gas Hydrate Field Trial, this experiment involved three stages: 1) the injection of a N2-CO2 mixture into a targeted hydrate-bearing layer, 2) a 4-day pressurized soaking period, and 3) a sustained depressurization and fluid production period. Data collected during the three stages of the field trial were made available after an extensive quality check. These data included continuous temperature and pressure logs, injected and recovered fluid compositions and volumes. The Ignik Sikumi #1 data set is extensive, but contains no direct evidence of the guest-molecule exchange process. This investigation is directed at using numerical simulation to provide an interpretation of the collected data. A numerical simulator, STOMP-HYDT-KE, was recently completed that solves conservation equations for energy, water, mobile fluid guest molecules, and hydrate guest molecules, for up to three gas hydrate guest molecules: CH4, CO2, and N2. The independent tracking of mobile fluid and hydrate guest molecules allows for the kinetic exchange of guest molecules between the mobile fluids and hydrate. The particular interest of this numerical investigation is to determine whether kinetic exchange parameters, determined from laboratory-scale experiments, are directly applicable to interpreting the Ignik Sikumi #1 data.« less

Monoenergetic reconstructions for imaging of coronary artery stents using spectral detector CT: In-vitro experience and comparison to conventional images.

PubMed

Hickethier, Tilman; Baeßler, Bettina; Kroeger, Jan Robert; Doerner, Jonas; Pahn, Gregor; Maintz, David; Michels, Guido; Bunck, Alexander C

Accurate assessment of coronary stents using non-invasive CT imaging remains challenging despite new stent materials and improvements in CT technology. Virtual monoenergetic (monoE) images reconstructed from dual energy CT acquisitions potentially decrease artifacts caused by coronary stents. A novel spectral detector technology provides monoE and conventional images simultaneously for all conducted scans. The purpose of our study was to systematically investigate the influence of different monoE reconstructions on the visualization of coronary stent lumen in comparison to conventional images. Ten different coronary stents (diameter 3.0 mm) embedded in plastic tubes filled with contrast agent (500 HU) were scanned with a 128-row spectral detector CT (IQon, Philips, 120 kV, 125 mAs). Images were reconstructed (0.67 mm slice thickness, 0.35 mm increment) with a stent-specific conventional reconstruction kernel and 6 different monoE settings (60, 70, 80, 90, 100, 150 keV). Image quality for each stent and reconstruction was quantified using established parameters: image noise (standard deviation (SD) within a standardized ROI), in-stent attenuation difference (mean attenuation difference between stented and non-stented lumen) and visible lumen diameter (mean visible diameter of the stented tube). Image noise was significantly lower in all monoE data dets compared to conventional images (conventional: 13.41, 60 keV: 11.62, 70 keV: 11.67, 80 keV: 11.69, 90 keV: 11.71, 100 keV: 11.75, 150 keV: 11.80 HU SD; p < 0.01). The in-stent attenuation difference was significantly smaller in monoE data with higher keV levels than in conventional images (conventional: 148.18, 60 keV: 154.13 p = 0.036, 70 keV: 143.43 p = 0.109, 80 keV: 137.25 p = 0.052, 90 keV: 133.02 p = 0.043, 100 keV: 130.12 p = 0.039, 150 keV: 123.99 HU p = 0.035). The visible lumen diameter was significantly greater in monoE data with higher keV levels than in conventional images (conventional: 0.65, 60 keV: 0.68 p = 0.542, 70 keV: 0.71 p = 0.053, 80 keV: 0.74 p < 0.01, 90 keV: 0.77 p < 0.01, 100 keV: 0.82 p < 0.01, 150 keV: 0.87 mm p < 0.01). In comparison to conventional CT images, well-established parameters for objective assessment of CT image quality for coronary stents are significantly improved by utilization of monoE reconstructions with adequate keV levels derived from data acquired on a novel spectral detector CT platform. Copyright © 2017 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

Investing in International Information Exchange Activities to Improve the Safety, Cost Effectiveness and Schedule of Cleanup - 13281

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seed, Ian; James, Paula; Mathieson, John

2013-07-01

With decreasing budgets and increasing pressure on completing cleanup missions as quickly, safely and cost-effectively as possible, there is significant benefit to be gained from collaboration and joint efforts between organizations facing similar issues. With this in mind, the US Department of Energy (DOE) and the UK Nuclear Decommissioning Authority (NDA) have formally agreed to share information on lessons learned on the development and application of new technologies and approaches to improve the safety, cost effectiveness and schedule of the cleanup legacy wastes. To facilitate information exchange a range of tools and methodologies were established. These included tacit knowledge exchangemore » through facilitated meetings, conference calls and Site visits as well as explicit knowledge exchange through document sharing and newsletters. A DOE web-based portal has been established to capture these exchanges and add to them via discussion boards. The information exchange is operating at the Government-to-Government strategic level as well as at the Site Contractor level to address both technical and managerial topic areas. This effort has resulted in opening a dialogue and building working relationships. In some areas joint programs of work have been initiated thus saving resource and enabling the parties to leverage off one another activities. The potential benefits of high quality information exchange are significant, ranging from cost avoidance through identification of an approach to a problem that has been proven elsewhere to cost sharing and joint development of a new technology to address a common problem. The benefits in outcomes significantly outweigh the costs of the process. The applicability of the tools and methods along with the lessons learned regarding some key issues is of use to any organization that wants to improve value for money. In the waste management marketplace, there are a multitude of challenges being addressed by multiple organizations and the effective pooling and exchange of knowledge and experience can only be of benefit to all participants to help complete the cleanup mission more quickly and more cost effectively. This paper examines in detail the tools and processes used to promote information exchange and the progress made to date. It also discusses the challenges and issues involved and proposes recommendations to others who are involved in similar activities. (authors)« less

26 CFR 1.1441-2 - Amounts subject to withholding.

Code of Federal Regulations, 2011 CFR

2011-04-01

... registered owner that is a financial institution within the meaning of section 871(h)(5)(B) or a member of a... price of an obligation sold or exchanged between interest payment dates, unless the sale or exchange is... knowledge or reason to know of such plan; (6) Original issue discount paid as part of the purchase price of...

77 FR 75459 - Self-Regulatory Organizations; BATS Exchange, Inc.; Notice of Filing of a Proposed Rule Change To...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-20

... both sides would participate in an Exchange Auction, this proposed change would aid in price discovery... auction price. This proposed change would aid in price discovery and help to reduce the likelihood of... Sell Shares and, therefore, a User would never have complete knowledge of liquidity available on both...

Integrated System Approach to Sustainability: Bio-Fuels and Bio-Refineries

ERIC Educational Resources Information Center

Elnashaie, Said S. E. H.; Fateen, Seif-Eddeen; El-Ahwany, Ahmed; Moustafa, Tarek M.

2008-01-01

The ISA, based on system theory, is the best way to organize knowledge and exchange it. It depends on defining every system through its boundary, main processes within this boundary, and exchange with the environment through this boundary. It relies upon thermodynamics and information theory and is, therefore, applicable to all kinds of systems,…

Intergenerational Exchange of Knowledge, Skills, Values and Practices between Self-Organized Active Citizens in Maribor, Slovenia

ERIC Educational Resources Information Center

Krašovec, Sabina Jelenc; Gregorcic, Marta

2017-01-01

Our paper deals with intergenerational informal learning developed by participatory democracy process in the Self-organized District Communities (SDC) in Maribor, the second largest city in Slovenia. It is based on the assumption that SDC assemblies, being safe and trustworthy, are very powerful spaces for behavioural and values exchange between…

22 CFR Appendix B to Part 62 - Exchange Visitor Program Services, Exchange-Visitor Program Application

Code of Federal Regulations, 2011 CFR

2011-04-01

...) 13. I certify that information given in this application is true to the best of my knowledge and belief and that I have completed appropriate information on reverse of this form. Signature of... prior to filling out this data). 6-7. Complete information on program sponsor. 8-11. Complete...

22 CFR Appendix B to Part 62 - Exchange Visitor Program Services, Exchange-Visitor Program Application

Code of Federal Regulations, 2012 CFR

2012-04-01

...) 13. I certify that information given in this application is true to the best of my knowledge and belief and that I have completed appropriate information on reverse of this form. Signature of... prior to filling out this data). 6-7. Complete information on program sponsor. 8-11. Complete...

22 CFR Appendix B to Part 62 - Exchange Visitor Program Services, Exchange-Visitor Program Application

Code of Federal Regulations, 2013 CFR

2013-04-01

...) 13. I certify that information given in this application is true to the best of my knowledge and belief and that I have completed appropriate information on reverse of this form. Signature of... prior to filling out this data). 6-7. Complete information on program sponsor. 8-11. Complete...

22 CFR Appendix B to Part 62 - Exchange Visitor Program Services, Exchange-Visitor Program Application

Code of Federal Regulations, 2014 CFR

2014-04-01

...) 13. I certify that information given in this application is true to the best of my knowledge and belief and that I have completed appropriate information on reverse of this form. Signature of... prior to filling out this data). 6-7. Complete information on program sponsor. 8-11. Complete...

An Approach to Semantic Interoperability for Improved Capability Exchanges in Federations of Systems

ERIC Educational Resources Information Center

Moschoglou, Georgios

2013-01-01

This study seeks an affirmative answer to the question whether a knowledge-based approach to system of systems interoperation using semantic web standards and technologies can provide the centralized control of the capability for exchanging data and services lacking in a federation of systems. Given the need to collect and share real-time…

Organizational Commitment for Knowledge Workers: The Roles of Perceived Organizational Learning Culture, Leader-Member Exchange Quality, and Turnover Intention

ERIC Educational Resources Information Center

Joo, Baek-Kyoo

2010-01-01

This article investigates the impact of perceived organizational learning culture and leader-member exchange (LMX) quality on organizational commitment and eventually on employee turnover intention. Employees exhibited the highest organizational commitment when they perceived a higher learning culture and when they were supervised in a supportive…

The Education Connection: Christopher Columbus to Sherman Alexie.

ERIC Educational Resources Information Center

Connell-Szasz, Margaret

1999-01-01

Educational exchange between American Indians and outsiders is examined in three periods. From first contact to the mid-1800s, knowledge was exchanged relatively equally. From the mid-1800s to the mid-1900s, acculturation was imposed upon American Indians. The political liberalism of the 1960s spawned renewed interest in Indian culture and rights,…

Dialogic Exchanges and the Negotiation of Differences: Female Graduate Students' Experiences of Obstacles Related to Academic Mentoring

ERIC Educational Resources Information Center

Hayes, Sharon; Koro-Ljungberg, Mirka

2011-01-01

This study, framed by social constructionism, investigated the dialogic exchanges and co-construction of knowledge among female graduate students, who met to discuss the ways in which the differences between mentors and mentees might be negotiated in order to develop and maintain mentoring relationships that benefit both partners. Ten female…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nesaraja, C.D.; McCutchan, E.A.

Available information pertaining to the nuclear structure of all nuclei with mass numbers A=41 ranging from Al (Z=13) to Ti (Z=22) are presented. The experimental reaction and decay data are evaluated and any inconsistencies or discrepancies are noted. The adopted values for various level properties (such as the spin, parity and and halflife) and gamma properties (energy, intensity and multipole character) are given. Since the prior evaluation several new measurements have expanded our knowledge of A=41 nuclides. The half-life of the ground state of {sup 41}Si has been determined and a single excited state identified. Excited levels in {sup 41}Pmore » have been observed for the first time. In {sup 41}Cl, seven new excited states have been identified in deep inelastic and heavy ion transfer reactions. Half-lifes for four states in {sup 41}Ar have been updated and additional levels with gammas have been included from a new measurement using the multiple ion transfer reaction. In {sup 41}Ca via charge-exchange reaction measurements, several new excited states were observed. A number of new resonances in {sup 41}K have been identified via the (p,γ) reaction. There remains a significant discrepancy in the half-life of the first excited state (980 keV) in {sup 41}K, with measurements differing by more than an order of magnitude. Transfer reactions suggest that this M1 transition should be l-forbidden, however, several measurements yield a lifetime which suggests a sizable M1 strength. Further measurements to resolve the current conflicts would be beneficial.« less

Nuclear Data Sheets for A = 41

DOE PAGES

Nesaraja, C. D.; McCutchan, E. A.

2016-03-01

Available information pertaining to the nuclear structure of all nuclei with mass numbers A=41 ranging from Al (Z=13) to Ti (Z=22) are presented. The experimental reaction and decay data are evaluated and any inconsistencies or discrepancies are noted. The adopted values for various level properties (such as the spin, parity and and halflife) and gamma properties (energy, intensity and multipole character) are given. Since the prior evaluation several new measurements have expanded our knowledge of A=41 nuclides. The half–life of the ground state of 41Si has been determined and a single excited state identified. Excited levels in 41P have beenmore » observed for the first time. In 41Cl, seven new excited states have been identified in deep inelastic and heavy ion transfer reactions. Half–lifes for four states in 41Ar have been updated and additional levels with gammas have been included from a new measurement using the multiple ion transfer reaction. In 41Ca via charge–exchange reaction measurements, several new excited states were observed. A number of new resonances in 41K have been identified via the (p, γ ) reaction. There remains a significant discrepancy in the half–life of the first excited state (980 keV) in 41K, with measurements differing by more than an order of magnitude. Transfer reactions suggest that this M1 transition should be l–forbidden, however, several measurements yield a lifetime which suggests a sizable M1 strength. Further measurements to resolve the current conflicts would be beneficial.« less

Tear exchange and contact lenses: a review.

PubMed

Muntz, Alex; Subbaraman, Lakshman N; Sorbara, Luigina; Jones, Lyndon

2015-01-01

Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

Operation of an ADR using helium exchange gas as a substitute for a failed heat switch

NASA Astrophysics Data System (ADS)

Shirron, P.; DiPirro, M.; Kimball, M.; Sneiderman, G.; Porter, F. S.; Kilbourne, C.; Kelley, R.; Fujimoto, R.; Yoshida, S.; Takei, Y.; Mitsuda, K.

2014-11-01

The Soft X-ray Spectrometer (SXS) is one of four instruments on the Japanese Astro-H mission, which is currently planned for launch in late 2015. The SXS will perform imaging spectroscopy in the soft X-ray band (0.3-12 keV) using a 6 × 6 pixel array of microcalorimeters cooled to 50 mK. The detectors are cooled by a 3-stage adiabatic demagnetization refrigerator (ADR) that rejects heat to either a superfluid helium tank (at 1.2 K) or to a 4.5 K Joule-Thomson (JT) cryocooler. Four gas-gap heat switches are used in the assembly to manage heat flow between the ADR stages and the heat sinks. The engineering model (EM) ADR was assembled and performance tested at NASA/GSFC in November 2011, and subsequently installed in the EM dewar at Sumitomo Heavy Industries, Japan. During the first cooldown in July 2012, a failure of the heat switch that linked the two colder stages of the ADR to the helium tank was observed. Operation of the ADR requires some mechanism for thermally linking the salt pills to the heat sink, and then thermally isolating them. With the failed heat switch unable to perform this function, an alternate plan was devised which used carefully controlled amounts of exchange gas in the dewar's guard vacuum to facilitate heat exchange. The process was successfully demonstrated in November 2012, allowing the ADR to cool the detectors to 50 mK for hold times in excess of 10 h. This paper describes the exchange-gas-assisted recycling process, and the strategies used to avoid helium contamination of the detectors at low temperature.

Operation of an ADR Using Helium Exchange Gas as a Substitute for a Failed Heat Switch

NASA Technical Reports Server (NTRS)

Shirron, P.; DiPirro, M.; Kimball, M.; Sneiderman, G.; Porter, F. S.; Kilbourne, C.; Kelley, R.; Fujimoto, R.; Yoshida, S.; Takei, Y.;

Understanding and Improving Knowledge Transactions in Command and Control

DTIC Science & Technology

2003-06-01

implications for the development of tools to facilitate efficient and effectiv and knowledge exchange. Cognitive task analysis (CTA) in support...makers]?” *quotes taken from K-web cognitive task analysis , Global 2000 and Global 2001 War Games, interviews with Carl Vinson K-Web users following

Personal Knowledge Integrators

ERIC Educational Resources Information Center

White, David C.

2013-01-01

This paper discusses, in the context of personal learning environments, the need for Personal Knowledge Integrators--PKI's or Knowers. It first illustrates and establishes the need for Knowers with usage scenarios and people's requirements. It then describes the elements required to make a Knower which can exchange information with other Knowers,…

Global Properties of the Heliospheric Termination Shock as inferred from Energetic Neutral Atoms measured by the Interstellar Boundary Explorer (IBEX)

NASA Astrophysics Data System (ADS)

Desai, Mihir; Heerikhuisen, Jacob; McComas, David; Pogorelov, Nikolai; Zank, Gary; Dayeh, Maher; Schwadron, Nathan; Allegrini, Frederic; Zirnstein, Eric

Energetic Neutral Atoms (ENAs) observed by the Interstellar Boundary Explorer (IBEX) provide powerful diagnostics about the origin of the progenitor ion populations and the physical mechanisms responsible for their production. Desai et al. (2012; 2013) combined and compared ENA spectra from the first three years of observations by the IBEX-Hi and -Lo ENA imagers along the lines-of-sights (LOS) from the inner heliosphere through to the locations of Voyager 1 and 2 with results from an updated physics-based model of the 3D heliosphere and its constituent ion populations. These results showed that (1) IBEX ENA fluxes and spectra above ˜0.7 keV measured along the LOS of the Voyagers are consistent with several models in which the parent pickup (PUI) populations originate in the inner heliosheath, and (2) a significant fraction of lower-energy ENAs between ˜0.1-0.5 keV may originate from interstellar neutral gas charge-exchanging with a non-thermalized (hot) population of PUIs in the outer heliosheath beyond the heliopause. We use these results and model the full sky IBEX-Hi energy spectra to probe the microphysical processes occurring in the inner heliospheath near the termination shock and then infer the global properties (e.g., latitudinal and longitudinal variations of the shock compression ratio) of the termination shock.

Interaction of ring current and radiation belt protons with ducted plasmaspheric hiss. 1: Diffusion coefficients and timescales

NASA Technical Reports Server (NTRS)

Kozyra, J. U.; Rasmussen, C. E.; Miller, R. H.; Lyons, L. R.

1994-01-01

Protons that are convected into the inner magnetosphere in response to enhanced magnetic activity can resonate with ducted plasmaspheric hiss in the outer plasmasphere via an anomalous Doppler-shifted cyclotron resonance. Plasmaspheric hiss is a right-hand-polarized electromagnetic emission that is observed to fill the plasmasphere on a routine basis. When plasmaspheric hiss is confined within field-aligned ducts or guided along density gradients, wave normal angles remain largely below 45 deg. This allows resonant interactions with ions at typical ring current and radiation belt energies to take place. Such field-aligned ducts have been observed both within the plasmasphere and in regions outside of the plasmasphere. Wave intensities are estimated using statistical information from studies of detached plasma regions. Diffusion coefficients are presented for a range of L shells and proton energies for a fixed wave distribution. Harmonic resonances in the range N = +/-100 are considered in order to include interactions between hiss at 100 Hz to 2 kHz frequencies, and protons in the energy range between approximately 10 keV and 1000 keV. Diffusion timescales are estimated to be of the order of tens of days and comparable to or shorter than lifetimes for Coulomb decay and charge exchange losses over most of the energy and spatial ranges of interest.

High energy-resolution measurement of the Se 82 ( He 3 , t ) Br 82 reaction for double- β decay and for solar neutrinos

DOE PAGES

Frekers, D.; Alanssari, M.; Adachi, T.; ...

2016-07-21

For this study, a high-resolution ( 3He,t) charge-exchange experiment at an incident energy of 420 MeV has been performed on the double beta (ββ) decay nucleus 82Se. A detailed Gamow-Teller (GT -) strength distribution in 82Br has been extracted, which provides information to the ββ-decay nuclear matrix elements. Three strong and isolated transitions, which are to the 75, 1484 and the 2087 keV states in 82Br, are found to dominate the low-excitation region below ≈ 2.1 MeV. Above 2.1 MeV a sudden onset of a strong GT fragmentation is observed. The degree of fragmentation resembles a situation found in themore » neighboring A = 76 system 76Ge, whereas the observed concentration of strength in the three low-lying states is reminiscent of the heavier neighbors 96Zr and 100Mo. The strong GT transition to the 75 keV (1 +) state makes 82Se interesting for solar neutrino detection. The 82Se(ν e,e -) 82Br solar neutrino capture rate in a nonoscillation scenario is therefore evaluated to 668 ± 12(stat) ± 60(sys) SNU, and some of the advantages of using selenium for solar neutrino studies are discussed.« less

Universal seesaw and 0νββ in new 3331 left-right symmetric model

NASA Astrophysics Data System (ADS)

Borah, Debasish; Patra, Sudhanwa

2017-08-01

We consider a class of left-right symmetric model with enlarged gauge group SU(3)c × SU(3)L × SU(3)R × U(1)X without having scalar bitriplet. In the absence of scalar bitriplet, there is no Dirac mass term for fermions including usual quarks and leptons. We introduce new isosinglet vector-like fermions so that all the fermions get their masses through a universal seesaw mechanism. We extend our discussion to neutrino mass and its implications in neutrinoless double beta decay (0 νββ). We show that for TeV scale SU(3)R gauge bosons, the heavy-light neutrino mixing contributes dominantly to 0 νββ that can be observed at ongoing experiments. The new physics contributions arising from purely left-handed currents via exchange of keV scale right-handed neutrinos and the so called mixed helicity λ-diagram can saturate the KamLANDZen bound. We show that the right handed neutrinos in this model can have mass in the sub keV range and can be long lived compared to the age of the Universe. The contributions of these right handed neutrinos to flavour physics observables like μ → eγ and muon g - 2 is also discussed. Towards the end we also comment on different possible symmetry breaking patterns of this enlarged gauge symmetry to that of the standard model.

Experiences of Knowledge Brokering for Evidence-Informed Public Health Policy and Practice: Three Years of the Scottish Collaboration for Public Health Research and Policy

ERIC Educational Resources Information Center

Frost, Helen; Geddes, Rosemary; Haw, Sally; Jackson, Caroline A.; Jepson, Ruth; Mooney, John D.; Frank, John

2012-01-01

Despite a burgeoning literature on, and widespread interest in, knowledge translation and exchange in public health, few articles provide an account of the actual experiences of knowledge brokerage organisations. The Scottish Collaboration for Public Health Research and Policy (SCPHRP) was formed in 2008 to: identify public health interventions…

Sustaining Knowledge Exchange and Research Impact in the Social Sciences and Humanities: Investing in Knowledge Broker Roles in UK Universities

ERIC Educational Resources Information Center

Lightowler, Claire; Knight, Christine

2013-01-01

Over the last decade, higher education policy in the United Kingdom (UK) has increasingly focused on the impact of academic research. This has resulted in the emergence of specialist knowledge brokers within UK universities in the social sciences and humanities. Our empirical research identified a tension between the research impact agenda and the…

Carotid dual-energy CT angiography: Evaluation of low keV calculated monoenergetic datasets by means of a frequency-split approach for noise reduction at low keV levels.

PubMed

Riffel, Philipp; Haubenreisser, Holger; Meyer, Mathias; Sudarski, Sonja; Morelli, John N; Schmidt, Bernhard; Schoenberg, Stefan O; Henzler, Thomas

2016-04-01

Calculated monoenergetic ultra-low keV datasets did not lead to improved contrast-to-noise ratio (CNR) due to the dramatic increase in image noise. The aim of the present study was to evaluate the objective image quality of ultra-low keV monoenergetic images (MEIs) calculated from carotid DECT angiography data with a new monoenergetic imaging algorithm using a frequency-split technique. 20 patients (12 male; mean age 53±17 years) were retrospectively analyzed. MEIs from 40 to 120 keV were reconstructed using the monoenergetic split frequency approach (MFSA). Additionally MEIs were reconstructed for 40 and 50 keV using a conventional monoenergetic (CM) software application. Signal intensity, noise, signal-to-noise ratio (SNR) and CNR were assessed in the basilar, common, internal carotid arteries. Ultra-low keV MEIs at 40 keV and 50 keV demonstrated highest vessel attenuation, significantly greater than those of the polyenergetic images (PEI) (all p-values <0.05). The highest SNR level and CNR level was found at 40 keV and 50 keV (all p-values <0.05). MEIs with MFSA showed significantly lower noise levels than those processed with CM (all p-values <0.05) and no significant differences in vessel attenuation (p>0.05). Thus MEIs with MFSA showed significantly higher SNR and CNR compared to MEIs with CM. Combining the lower spatial frequency stack for contrast at low keV levels with the high spatial frequency stack for noise at high keV levels (frequency-split technique) leads to improved image quality of ultra-low keV monoenergetic DECT datasets when compared to previous monoenergetic reconstruction techniques without the frequency-split technique. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

FLIS Procedures Manual. Materiel Management Decision Rule Tables.

DTIC Science & Technology

1996-10-01

U5 C PA FAPA DF PA 06 TA 67 PA PA TU PA TU PA FEPA DF PA 06 SE 67 PA PA TU PA TU PA FGPA DF PA 06 TG 67 PA PA TU PA TU PA FJPA DF PA 06 SJ 67 PA PA SJ...AJ TU AJ TU TA FAJ4 DF AJ 22 TA 97 AJ AJ TU AJ TU TA FAKE DF KE 06 TA 67 KE KE TU KE TU TA FAKZ DF KZ 01 TA 5D KZ KZ TU KZ TU I TA FAPA DF PA 06 TA...AJ TU TU FAJ5 DF AJ 22 TG 97 AJ AJ TU AJ TU TU FAKE DF KE 06 TA 67 KE KE TU KE TU TU FAPA DF PA 01 TA 67 PA PA TU PA TU TU FATC DF AZ 22 TA 8D AZ AZ

Optical Diagnostics for Flow Control on Small Wings

DTIC Science & Technology

2016-07-13

0.01 0 0.01 0.02 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 w/ U ∞ y/b δ= 0˚, KE δ= 0˚, NKE δ= 2 ˚, KE δ= 4˚, KE δ= 6˚, KE δ= 4˚, 6˚, NKE δ= 8...0.02 -0.6 -0.5 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 w/ U ∞ y/b δ= 0˚, KE δ= 0˚, NKE δ= 4˚, KE δ= 4˚, NKE δ= 6˚, KE δ= 6˚, NKE y x KE Fig. 2 The...Liebenberg L & Spedding GR 2016 On the wing density and the Inflation Factor of aircraft . Aero. J. 120, 291-312. 2 . New discoveries, inventions, or

Functional impairment of skeletal muscle oxidative metabolism during knee extension exercise after bed rest.

PubMed

Salvadego, Desy; Lazzer, Stefano; Marzorati, Mauro; Porcelli, Simone; Rejc, Enrico; Simunic, Bostjan; Pisot, Rado; di Prampero, Pietro Enrico; Grassi, Bruno

2011-12-01

A functional evaluation of skeletal muscle oxidative metabolism during dynamic knee extension (KE) incremental exercises was carried out following a 35-day bed rest (BR) (Valdoltra 2008 BR campaign). Nine young male volunteers (age: 23.5 ± 2.2 yr; mean ± SD) were evaluated. Pulmonary gas exchange, heart rate and cardiac output (by impedance cardiography), skeletal muscle (vastus lateralis) fractional O(2) extraction, and brain (frontal cortex) oxygenation (by near-infrared spectroscopy) were determined during incremental KE. Values at exhaustion were considered "peak". Peak heart rate (147 ± 18 beats/min before vs. 146 ± 17 beats/min after BR) and peak cardiac output (17.8 ± 3.3 l/min before vs. 16.1 ± 1.8 l/min after BR) were unaffected by BR. As expected, brain oxygenation did not decrease during KE. Peak O(2) uptake was lower after vs. before BR, both when expressed as liters per minute (0.99 ± 0.17 vs. 1.26 ± 0.27) and when normalized per unit of quadriceps muscle mass (46.5 ± 6.4 vs. 56.9 ± 11.0 ml·min(-1)·100 g(-1)). Skeletal muscle peak fractional O(2) extraction, expressed as a percentage of the maximal values obtained during a transient limb ischemia, was lower after (46.3 ± 12.1%) vs. before BR (66.5 ± 11.2%). After elimination, by the adopted exercise protocol, of constraints related to cardiovascular O(2) delivery, a decrease in peak O(2) uptake and muscle peak capacity of fractional O(2) extraction was found after 35 days of BR. These findings suggest a substantial impairment of oxidative function at the muscle level, "downstream" with respect to bulk blood flow to the exercising muscles, that is possibly at the level of blood flow distribution/O(2) utilization inside the muscle, peripheral O(2) diffusion, and intracellular oxidative metabolism.

Overview of Results from the Cassini Magnetospheric Imaging Instrument (MIMI) During the First Year of Operations

NASA Technical Reports Server (NTRS)

Krimigis, S. M.; Mitchell, D. G.; Hamilton, D. C.; Krupp, N.; Livi, S.; Roelof, E. C.; Dandouras, J.; Mauk, B. H.; Brandt, J. P.; Paranicas, C.

2005-01-01

The MIMI investigation comprises three sensors covering the indicated energy ranges: the Ion and Neutral Camera (INCA) -- 7 keV/nuc 3 Mev) and protons (1.6 < E < 160 Mev) from the back end of the dual field-of-view telescope. The Saturn observation sequences began in January, 2004 and culminated in Saturn Orbit Insertion on July 1, 2004. The MIMI sensors observed substantial activity in interplanetary space for several months prior to SOI, including several interplanetary shocks associated with corotating interaction regions, numerous increases most likely originating from particle streams in the vicinity of the Saturnian bow shock and energetic neutral atoms (ENA) emanating from Saturn s magnetosphere. Results following SOI revealed: a dynamical magnetosphere with a day-night asymmetry and an 11-hour periodicity; several water-product ions (O+, OH+, H2O+), but little N+; inferred quantities of neutral gas sufficient to cause major losses in the trapped ions and electrons in the middle and inner magnetosphere; a Titan exosphere that is a copious source of ENA; INCA imaging through ENA has also revealed a previously unknown radiation belt residing inward of the D-ring that is most likely the result of double charge-exchange between the main radiation belt and the upper layers of Saturn s exosphere. Finally, there is ample evidence for the presence of substorm-like injections of plasma that subsequently corotates for a number of days before dissipating on the night-side magnetotail. The observations will be presented and discussed in the context of current theoretical models.

Modeling the near-Earth interaction between ring current ions and exospheric neutrals: escape through energetic neutral atoms (ENAs)

NASA Astrophysics Data System (ADS)

LLera, K.; Goldstein, J.; McComas, D. J.; Valek, P. W.

2016-12-01

The two major loss processes for ring current decay are precipitation and energetic neutral atoms (ENAs). Since the exospheric neutral density increases with decreasing altitudes, precipitating ring current ions (reaching down to 200 - 800 km in altitude) also produce low-altitude ENA signatures that can be stronger than the ring current emission at equatorial distances ( 2 - 9 Re). The higher density results in multiple collisions between the ring current ions and exospheric oxygen. The affect on hydrogen ions is the focus of this study. Since the H particle sustains energy loss ( 36 eV) at each neutralizing or re-ionizing interaction, the escaped ENAs do not directly reflect the ring current properties. We model the energy loss due to multiple charge exchange and electron stripping interactions of 1 - 100 keV precipitating ring current ions undergo before emerging as low-altitude ENAs. The H particle is either an ion or an ENA throughout the simulation. Their lifetime is analytically determined by the length of one mean free path. We track the ion state with Lorentz motion while the ENA travels ballistically across the geomagnetic field. Our simulations show the energy loss is greater than 20% for hydrogen ring current ions below 30 keV (60 keV for the simulations that wander equatorward). This is the first quantification of the energy loss associated with the creation of low-altitude ENAs. Our model (currently constrained in the meridional plane) has revealed characteristics on how precipitation is affected by the near-Earth neutral exosphere. This ion-neutral interaction removes particles from the loss cone but promotes loss through ENA generation. These findings should be implemented in models predicting the ring current decay and used as an analysis tool to reconstruct the ring current population from observed low-altitude ENAs.

Chandra ACIS Observations of Jovian X-Ray Emission

NASA Technical Reports Server (NTRS)

Garmire, Gordon; Elsner, Ronald; Feigelson, Eric; Ford, Peter; Gladstone, G. Randall; Hurley, Kevin; Metzger, Albert; Waite, J. Hunter, Jr.; Whitaker, Ann F. (Technical Monitor)

2001-01-01

On November 25 and 26, 1999, the Chandra X-ray spacecraft conducted a set of four 19,000 sec observations of Jupiter. The ACIS-S instrument configuration was used for its good low energy efficiency and spatial resolution. An anomalous response was obtained which was subsequently attributed to strong jovian infrared radiation penetrating the detector and piling up spurious events across the entire X-ray range. However, the pre-observation establishment of an offsetting bias field has allowed the recovery of data from that portion of Jupiter's disc which remained within the elevated portion of the bias field during the observation. This ranges from fewer than 3000 sec to the entire observing time for about 10% of the planet. Auroral emission is seen near both poles in each observation. The northern aurora ia overall more intense than the southern, consistent with prior Einstein and ROSAT Observatory results. The southern aurora shows more modulation with Jupiter's rotation than the northern. Spatial resolution has been improved by at least a factor of two over prior measurements but convincing evidence of structure has not been seen. Lower latitude emission, first observed by ROSAT, is confirmed with flux levels averaging more than a factor of five below peak auroral values. Pronounced variation in the observed emission has occurred over the observing period. The spectral response extends from 0.24 keV, below which noise dominates, to about 1.2 keV. For all four observations the spectrum is clearly enhanced between 0.45 and 0.85 keV. This is apparently unequivocal evidence that Jupiter's X-ray emission is the result of oxygen and perhaps sulfur ions precipitating into the planet's atmosphere, where they undergo charge exchange interactions. The identification of specific transitions lines in the spectrum is among the ongoing efforts. A bremsstrahlung component has not yet been identified.

Development of a collinear laser spectrometer facility at VECC: First test result

NASA Astrophysics Data System (ADS)

Ali, Md Sabir; Ray, Ayan; Raja, Waseem; Bandyopadhyay, Arup; Naik, Vaishali; Polley, Asish; Chakrabarti, Alok

2018-04-01

We report here the development of collinear laser spectroscopy (CLS) system at VECC for the study of hyperfine spectrum and isotopic shift of stable and unstable isotopes. The facility is first of its kind in the country allowing measurement of hyperfine splitting of atomic levels using atomic beams. The CLS system is installed downstream of the focal plane of the existing isotope separator online (ISOL) facility at VECC and is recently commissioned by successfully resolving the fluorescence spectrum of the hyperfine levels in ^{85,87}Rb. The atomic beams of Rb were produced by charge exchange of 8 keV Rb ion beam which were produced, extracted and transported to the charge exchange cell using the ion sources, extractor and the beam-line magnets of the ISOL facility. The laser propagating opposite to the ion / atom beam direction was allowed to interact with the atom beam and fluorescence spectrum was recorded. The experimental set-up and the experiment conducted are reported in detail. The measures needed to be carried out for improving the sensitivity to a level necessary for studying short-lived exotic nuclei have also been discussed.

Defect structures induced by high-energy displacement cascades in γ uranium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miao, Yinbin; Beeler, Benjamin; Deo, Chaitanya

Displacement cascade simulations were conducted for the c uranium system based on molecular dynamics. A recently developed modified embedded atom method (MEAM) potential was employed to replicate the atomic interactions while an embedded atom method (EAM) potential was adopted to help characterize the defect structures induced by the displacement cascades. The atomic displacement process was studied by providing primary knock-on atoms (PKAs) with kinetic energies from 1 keV to 50 keV. The influence of the PKA incident direction was examined. The defect structures were analyzed after the systems were fully relaxed. The states of the self-interstitial atoms (SIAs) were categorizedmore » into various types of dumbbells, the crowdion, and the octahedral interstitial. The voids were determined to have a polyhedral shape with {110} facets. The size distribution of the voids was also obtained. The results of this study not only expand the knowledge of the microstructural evolution in irradiated c uranium, but also provide valuable references for the radiation-induced defects in uranium alloy fuels.« less

High accuracy experimental determination of copper and zinc mass attenuation coefficients in the 100 eV to 30 keV photon energy range

NASA Astrophysics Data System (ADS)

Ménesguen, Y.; Gerlach, M.; Pollakowski, B.; Unterumsberger, R.; Haschke, M.; Beckhoff, B.; Lépy, M.-C.

2016-02-01

The knowledge of atomic fundamental parameters such as mass attenuation coefficients with low uncertainties, is of decisive importance in elemental quantification using x-ray fluorescence analysis techniques. Several databases are accessible and frequently used within a large community of users. These compilations are most often in good agreement for photon energies in the hard x-ray ranges. However, they significantly differ for low photon energies and around the absorption edges of any element. In a joint cooperation of the metrology institutes of France and Germany, mass attenuation coefficients of copper and zinc were determined experimentally in the photon energy range from 100 eV to 30 keV by independent approaches using monochromatized synchrotron radiation at SOLEIL (France) and BESSY II (Germany), respectively. The application of high-accuracy experimental techniques resulted in mass attenuation coefficient datasets determined with low uncertainties that are directly compared to existing databases. The novel datasets are expected to enhance the reliability of mass attenuation coefficients.

Recoil Distance Lifetime Measurements of the Nuclei SAMARIUM-146 and EUROPIUM-147, Using Hydrogen-Iodide X Neutron Gamma) Reactions.

NASA Astrophysics Data System (ADS)

Rozak, Stephen

Recoil-distance lifetime measurements have been performed on several levels in ('146)Sm and ('147)Eu, using the reactions ('139)La(('11)B,4n)('146)Sm and ('139)La(('12)C,4n)('147)Eu. The data were analyzed with an algorithm incorporated into a computer code PLUNGER that treats arbitrarily complex cascade feeding in a new, mathematically rigorous, formalism. Higher order corrections are also incorporated into the code and are discussed. The measured mean lifetimes in ('146)Sm are 7ps (2(,1)('+), 747.2keV), 3ps (4(,1)('+), 1381.2keV), 125ps (6(,1)('+), 1811.5keV), 15.7ps (7(,1)('-), 2600.3keV), 16.4ps (8(,1)('+), 2737.1keV), 1.2ns (9(,1)('-), 2797.6keV), 38.8ps (9(,2)('-), 3354.5keV), 14.5ps (11(,1)('-), 3783.5keV), 7.1ps (11(,2)('-), 4091.2keV), 2.3ps (12('-), 4461.4keV), and 7.6ps (13('-), 4628.8keV). The lifetimes measured in ('147)Eu are 6.8ps (15/2('-), 1346.7keV), 12.2ps (19/2(' -), 1926.9keV), 137ps (23/2('-), 2293.2keV), 72.2ps (27/2(' -), 2900.9keV), and 33ps (23/2('-), 2996.9keV). The results for ('146)Sm were compared to calculations of the IBA model and cluster-vibrator model. Both models have good success reproducing the data up to the 6('+) -4('+) transition. They both fail to reproduce the transition probabilities for the 8('+)-6('+) transition. The data also support the interpretation of the lowest negative parity levels (3('-), 5('-),7('-),9('-),11(' -)) as being a band composed of an octupole phonon coupled to the ground state band. The data support the interpretation of the 11/2(' -), 15/2('-), 19/2('-), 23/2('-), and 27/2('-) levels in ('147)Eu as comprised of a valence nucleon coupled to the 0('+), 2('+), 4('+), 6('+), and 8('+) levels in ('146)Sm. The success of this work also demonstrates that the feeding problem is not insurmountable when applying Doppler shift recoil-distance techniques to nuclei formed by (HI,xn) reactions, even when complicated decay schemes are involved.

Lifetimes of $sup 55$Co excited levels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neal, G.F.; Chagnon, P.R.

1976-02-01

Gamma-rays deexciting $sup 55$CO levels have been studied in coincidence with deuterons detected in a particle telescope, in the $sup 54$Fe($sup 3$He,d$gamma$)$sup 55$Co reaction. Excitation energies, relative $gamma$-ray intensities, and Doppler-shift attenuations of 12 levels have been measured. Mean lifetimes and transition strengths are reported. The Doppler-shifted line shape of the 2164$Yields$0-keV transition has been analyzed and has been found consistent with the assumption of a single level. Lifetimes of selected levels are: 2164 keV, 125$sup +25$/sub -//sub 2//sub 0/ fs; 3301 keV, 50$sup +20$/sub -// sub 1//sub 5/ fs; 3322 keV, 45$sup +15$/sub -//sub 1//sub 0/ fs; 3641 keV,more » 300$sup +150$/sub -//sub 1//sub 0//sub 0/ fs; 4163 keV, 30$sup +15$/sub -//sub 1// sub 0/ fs; 4714 keV, 300$sup +200$/sub -//sub 1//sub 5//sub 0/ fs; 4719 keV, <30 fs; and 5172 keV, 10$sup +10$/sub -//sub 5/ fs. (AIP)« less

The Circulation and Silence of Weaving Knowledge in Contemporary Navajo Life

ERIC Educational Resources Information Center

Yohe, Jill Ahlberg

2012-01-01

This article draws upon ethnographic fieldwork within a Navajo community to illustrate how weaving knowledge and practices shape contemporary notions of community identity and belonging. The ongoing exchange of Navajo weaving taboos and the careful management of weaving teachings offers community members various opportunities to share and keep…

Student Teachers' Knowledge about Chemical Representations

ERIC Educational Resources Information Center

Taskin, Vahide; Bernholt, Sascha; Parchmann, Ilka

2017-01-01

Chemical representations serve as a communication tool not only in exchanges between scientists but also in chemistry lessons. The goals of the present study were to measure the extent of student teachers' knowledge about chemical representations, focusing on chemical formulae and structures in particular, and to explore which factors related to…

Eagle Racing: Addressing Corporate Collaboration Challenges through an Online Simulation Game

ERIC Educational Resources Information Center

Angehrn, Albert A.; Maxwell, Katrina

2009-01-01

Effective collaboration is necessary for corporation-wide learning, knowledge exchange, and innovation. However, it is difficult to create a corporate culture that encourages collaboration; the complexity of such collaboration is increased substantially by the diverse and distributed nature of knowledge sources and decision makers in the global…

75 FR 75727 - Implementing the Whistleblower Provisions of Section 23 of the Commodity Exchange Act

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-06

... corporate filings, media, and the Internet. Importantly, the proposed definition of ``independent knowledge..., or communications (subject to the exclusion for knowledge obtained from public sources). Thus, for... that was obtained through a communication that is subject to the attorney-client privilege. (Proposed...

The Biological Effectiveness of Accelerated Particles for the Induction of Chromosome Damage: Track Structure Effects and Cytogenetic Signatures of High-LET Exposure

NASA Technical Reports Server (NTRS)

George, K.; Hada, M.; Chappell, L.; Cucinotta, F. A.

2012-01-01

Track structure models predict that at a fixed value of LET, particles with lower charge number, Z will have a higher biological effectiveness compared to particles with a higher Z. In this report we investigated how track structure effects induction of chromosomal aberration in human cells. Human lymphocytes were irradiated in vitro with various energies of accelerated iron, silicon, neon, or titanium ions and chromosome damage was assessed in using three color FISH chromosome painting in chemically induced PCC samples collected a first cell division post irradiation. The LET values for these ions ranged from 30 to 195 keV/micrometers. Of the particles studied, Neon ions have the highest biological effectiveness for induction of total chromosome damage, which is consistent with track structure model predictions. For complex-type exchanges 64 MeV/ u Neon and 450 MeV/u Iron were equally effective and induced the most complex damage. In addition we present data on chromosomes exchanges induced by six different energies of protons (5 MeV/u to 2.5 GeV/u). The linear dose response term was similar for all energies of protons suggesting that the effect of the higher LET at low proton energies is balanced by the production of nuclear secondaries from the high energy protons. All energies of protons have a much higher percentage of complex-type chromosome exchanges than gamma rays, signifying a cytogenetic signature for proton exposures.

Prototype development of ion exchanging alpha detectors

NASA Astrophysics Data System (ADS)

Krupp, Dominik; Scherer, Ulrich W.

2018-07-01

In contemporary alpha particle spectrometry, the sample preparation is separated from the detection of the radionuclides. The sample preparation itself requires much time and the equipment of a radiochemistry lab. If sample preparation and detection could be combined in one step, a huge time-saving potential becomes available. One way to realize such a combination is described here. The concept was explored by simulations with the well-established computer programs SRIM and AASI. In a proof of concept, the active surface of commercially available alpha detectors was modified with sulfonic acid groups as a well-known type of cation exchanger. It was shown, that in contrast to a pristine detector, a chemically modified detector is able to extract uranium-238 and -234 selectively as uranyl cations onto the detector surface from a diluted [238/234U]uranyl acetate solution. It was possible to measure directly in the sample solution for one week or to prepare the modified detector surfaces within 30 s for measurements in conventional alpha chambers. In either case, the full width at half maximum of the measured spectra was around 100 keV, allowing a clear nuclide identification. After regenerating the cation exchanger surfaces by rinsing with hydrochloric acid the typical uranium spectra had disappeared, proving chemical bonding of the uranium. Due to the large variety of potential functional groups this new way of alpha spectrometry could be beneficial for all fields of alpha particle spectrometry, from environmental analysis, over security measurements to studies of the heaviest elements.

Retraction: Using the Medipix3 detector for direct electron imaging in the range 60 keV to 200 keV in electron microscopy Retraction: Using the Medipix3 detector for direct electron imaging in the range 60 keV to 200 keV in electron microscopy

NASA Astrophysics Data System (ADS)

Mir, J. A.; Plackett, R.; Shipsey, I.; dos Santos, J. M. F.

2018-01-01

The paper "Using the Medipix3 detector for direct electron imaging in the range 60keV to 200keV in electron microscopy" by J.A. Mir, R. Plackett, I. Shipsey and J.M.F. dos Santos has been retracted following the authors' request on the basis of the existence of a disagreement about the ownership of the data, to prevent conflict between collaborators.

Method for distributed object communications based on dynamically acquired and assembled software components

NASA Technical Reports Server (NTRS)

Sundermier, Amy (Inventor)

2002-01-01

A method for acquiring and assembling software components at execution time into a client program, where the components may be acquired from remote networked servers is disclosed. The acquired components are assembled according to knowledge represented within one or more acquired mediating components. A mediating component implements knowledge of an object model. A mediating component uses its implemented object model knowledge, acquired component class information and polymorphism to assemble components into an interacting program at execution time. The interactions or abstract relationships between components in the object model may be implemented by the mediating component as direct invocations or indirect events or software bus exchanges. The acquired components may establish communications with remote servers. The acquired components may also present a user interface representing data to be exchanged with the remote servers. The mediating components may be assembled into layers, allowing arbitrarily complex programs to be constructed at execution time.

Overview of the negative ion based neutral beam injectors for ITER

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schunke, B., E-mail: email@none.edu; Boilson, D.; Chareyre, J.

2016-02-15

The ITER baseline foresees 2 Heating Neutral Beams (HNB’s) based on 1 MeV 40 A D{sup −} negative ion accelerators, each capable of delivering 16.7 MW of deuterium atoms to the DT plasma, with an optional 3rd HNB injector foreseen as a possible upgrade. In addition, a dedicated diagnostic neutral beam will be injecting ≈22 A of H{sup 0} at 100 keV as the probe beam for charge exchange recombination spectroscopy. The integration of the injectors into the ITER plant is nearly finished necessitating only refinements. A large number of components have passed the final design stage, manufacturing has started,more » and the essential test beds—for the prototype route chosen—will soon be ready to start.« less

Extraction of highly charged ions from the Berlin Electron Beam Ion Trap for interactions with a gas target

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allen, F.I.; Biedermann, C.; Radtke, R.

2006-03-15

Highly charged ions are extracted from the Berlin Electron Beam Ion Trap for investigations of charge exchange with a gas target. The classical over-the-barrier model for slow highly charged ions describes this process, whereby one or more electrons are captured from the target into Rydberg states of the ion. The excited state relaxes via a radiative cascade of the electron to ground energy. The cascade spectra are characteristic of the capture state. We investigate x-ray photons emitted as a result of interactions between Ar{sup 17+} ions at energies {<=}5q keV with Ar atoms. Of particular interest is the velocity dependencemore » of the angular momentum capture state l{sub c}.« less

Dose--response of initial G2-chromatid breaks induced in normal human fibroblasts by heavy ions

NASA Technical Reports Server (NTRS)

Kawata, T.; Durante, M.; Furusawa, Y.; George, K.; Takai, N.; Wu, H.; Cucinotta, F. A.; Dicello, J. F. (Principal Investigator)

2001-01-01

PURPOSE: To investigate initial chromatid breaks in prematurely condensed G2 chromosomes following exposure to heavy ions of different LET. MATERIAL AND METHODS: Exponentially growing human fibroblast cells AG1522 were irradiated with gamma-rays, energetic carbon (13 keV/ microm, 80 keV/microm), silicon (55 keV/microm) and iron (140 keV/microm, 185keV/microm, 440keV/microm) ions. Chromosomes were prematurely condensed using calyculin-A. Initial chromatid-type and isochromatid breaks in G2 cells were scored. RESULTS: The dose response curves for total chromatid breaks were linear regardless of radiation type. The relative biological effectiveness (RBE) showed a LET-dependent increase, peaking around 2.7 at 55-80keV/microm and decreasing at higher LET. The dose response curves for isochromatid-type breaks were linear for high-LET radiations, but linear-quadratic for gamma-rays and 13 keV/microm carbon ions. The RBE for the induction of isochromatid breaks obtained from linear components increased rapidly between 13keV/microm (about 7) and 80keV/microm carbon (about 71), and decreased gradually until 440 keV/microm iron ions (about 66). CONCLUSIONS: High-LET radiations are more effective at inducing isochromatid breaks, while low-LET radiations are more effective at inducing chromatid-type breaks. The densely ionizing track structures of heavy ions and the proximity of sister chromatids in G2 cells result in an increase in isochromatid breaks.

The Joint Fire Science Program Fire Exchange Network: Facilitating Knowledge Exchange About Wildland Fire Science Across the U.S.

NASA Astrophysics Data System (ADS)

York, A.; Blocksome, C.; Cheng, T.; Creighton, J.; Edwards, G.; Frederick, S.; Giardina, C. P.; Goebel, P. C.; Gucker, C.; Kobziar, L.; Lane, E.; Leis, S.; Long, A.; Maier, C.; Marschall, J.; McGowan-Stinski, J.; Mohr, H.; MontBlanc, E.; Pellant, M.; Pickett, E.; Seesholtz, D.; Skowronski, N.; Stambaugh, M. C.; Stephens, S.; Thode, A.; Trainor, S. F.; Waldrop, T.; Wolfson, B.; Wright, V.; Zedler, P.

2014-12-01

The Joint Fire Science Program's (JFSP) Fire Exchange Network is actively working to accelerate the awareness, understanding, and adoption of wildland fire science information by federal, tribal, state, local, and private stakeholders within ecologically similar regions. Our network of 15 regional exchanges provides timely, accurate, and regionally relevant science-based information to assist with fire management challenges. Regional activities, through which we engage fire and resource managers, scientists, and private landowners, include online newsletters and announcements, social media, regionally focused web-based clearinghouses of relevant science, field trips and demonstration sites, workshops and conferences, webinars and online training, and syntheses and fact sheets. Exchanges also help investigators design research that is relevant to regional management needs and assist with technology transfer to management audiences. This poster provides an introduction to and map of the regional exchanges.

Quantification of left and right atrial kinetic energy using four-dimensional intracardiac magnetic resonance imaging flow measurements.

PubMed

Arvidsson, Per M; Töger, Johannes; Heiberg, Einar; Carlsson, Marcus; Arheden, Håkan

2013-05-15

Kinetic energy (KE) of atrial blood has been postulated as a possible contributor to ventricular filling. Therefore, we aimed to quantify the left (LA) and right (RA) atrial blood KE using cardiac magnetic resonance (CMR). Fifteen healthy volunteers underwent CMR at 3 T, including a four-dimensional phase-contrast flow sequence. Mean LA KE was lower than RA KE (1.1 ± 0.1 vs. 1.7 ± 0.1 mJ, P < 0.01). Three KE peaks were seen in both atria: one in ventricular systole, one during early ventricular diastole, and one during atrial contraction. The systolic LA peak was significantly smaller than the RA peak (P < 0.001), and the early diastolic LA peak was larger than the RA peak (P < 0.05). Rotational flow contained 46 ± 7% of total KE and conserved energy better than nonrotational flow did. The KE increase in early diastole was higher in the LA (P < 0.001). Systolic KE correlated with the combination of atrial volume and systolic velocity of the atrioventricular plane displacement (r(2) = 0.57 for LA and r(2) = 0.64 for RA). Early diastolic KE of the LA correlated with left ventricle (LV) mass (r(2) = 0.28), however, no such correlation was found in the right heart. This suggests that LA KE increases during early ventricular diastole due to LV elastic recoil, indicating that LV filling is dependent on diastolic suction. Right ventricle (RV) relaxation does not seem to contribute to atrial KE. Instead, RA KE generated during ventricular systole may be conserved in a hydraulic "flywheel" and transferred to the RV through helical flow, which may contribute to RV filling.

Elimination of scattered gamma rays from injection sites using upper offset energy windows in sentinel lymph node scintigraphy.

PubMed

Yoneyama, Hiroto; Tsushima, Hiroyuki; Onoguchi, Masahisa; Konishi, Takahiro; Nakajima, Kenichi; Kinuya, Seigo

2015-05-01

The identification of sentinel lymph nodes (SLNs) near injection sites is difficult because of scattered gamma rays. The purpose of this study was to investigate the optimal energy windows for elimination of scattered gamma rays in order to improve the detection of SLNs. The clinical study group consisted of 56 female patients with breast cancer. While the energy was centred at 140 keV with a 20% window for Tc-99m, this energy window was divided into five subwindows with every 4% in planar imaging. Regions of interest were placed on SLNs and the background, and contrast was calculated using a standard equation. The confidence levels of interpretations were evaluated using a five-grade scale. The contrast provided by 145.6 keV±2% was the best, followed by 140 keV±2%, 151.2 keV±2%, 134.4 keV±2% and 128.8 keV±2% in that order. When 128.8 keV±2% and 134.4 keV±2% were eliminated from 140 keV±10% (145.6 keV±6%), the contrast of SLNs improved significantly. The confidence levels of interpretation and detection rate provided by the planar images with 140 keV±10% were 4.74±0.58 and 94.8%, respectively, and those provided by 145.6 keV±6% were 4.94±0.20 and 100%. Because lower energy windows contain many scattered gamma rays, upper offset energy windows, which exclude lower energy windows, improve the image contrast of SLNs near injection sites.

A Review on Community-Based Knowledge Transfer and Exchange (KTE) Initiatives for Promoting Well-Being in Older Adults.

PubMed

Syed, M Anum; Moorhouse, Aynsley; McDonald, Lynn; Hitzig, Sander L

2017-01-01

Knowledge transfer and exchange (KTE) processes can facilitate evidence-informed community-based care for seniors, but understanding effective KTE in gerontology is limited. A scoping review was conducted to evaluate the current state of KTE in the community-based sector for seniors. Twelve articles met the inclusion criteria, which addressed a broad variety of topics including caregiving, elder abuse, falls prevention, home-rehabilitation, hospice and dementia care. Studies evaluated KTE practices (n = 8), developed a KTE intervention (n = 3), or explored research uptake (n = 1). Community-based initiatives for seniors informed by KTE processes are scarce, requiring further efforts at the research, practice and policy levels.

Representation and Exchange of Knowledge as a Basis of Information Processes. Proceedings of the International Research Forum in Information Science (5th, Heidelberg, West Germany, September 5-7, 1983).

ERIC Educational Resources Information Center

Dietschmann, Hans, Ed.

This 22-paper collection addresses a variety of issues related to representation and transfer of knowledge. Individual papers include an explanation of the usefulness of general scientific models versus case-specific approaches and a discussion of different empirical approaches to the general problem of knowledge representation for information…

[Transfer and sharing of public health knowledge: reflections on the components of a national information system in France].

PubMed

Cambon, Linda; Alla, François

2013-01-01

It is becoming increasingly necessary, in France, to develop a more efficient public health policy and define research in terms of the perspective of its use for public decisions and clinical practice. One possible solution consists of knowledge transfer and sharing based on a continuous exchange and interaction process between scientists and potential users of research data - field workers and health policy decision-makers. Such a process would involve collaboration with users to help them apply the evidence produced by research as well as the mobilization of research scientists to develop research more adapted to needs. This article defines the goals of development of knowledge transfer in the French setting. The conceptual bases are defined and four strategic axes and their operational modalities are developed. This proposal also integrates all of the public authorities concerned: promote knowledge transfer; reinforce observation and diffusion of evidence and its usability; promote the development of more adapted public health research by facilitating research scientist /research data user relationships; assist the various parties in the exchange and sharing of knowledge. Apart from improving the efficiency of health policies, the development of knowledge transfer and sharing would also strengthen the credibility of certain intervention strategies, especially in the field of prevention, by designing evidence-based strategies.

Disturbed left and right ventricular kinetic energy in patients with repaired tetralogy of Fallot: pathophysiological insights using 4D-flow MRI.

PubMed

Sjöberg, Pia; Bidhult, Sebastian; Bock, Jelena; Heiberg, Einar; Arheden, Håkan; Gustafsson, Ronny; Nozohoor, Shahab; Carlsson, Marcus

2018-04-17

Indications for pulmonary valve replacement (PVR) in patients with pulmonary regurgitation (PR) after repaired tetralogy of Fallot (rToF) are debated. We aimed to compare right (RV) and left ventricular (LV) kinetic energy (KE) measured by 4D-flow magnetic resonance imaging (MRI) in patients to controls, to further understand the pathophysiological effects of PR. Fifteen patients with rToF with PR > 20% and 14 controls underwent MRI. Ventricular volumes and KE were quantified from cine MRI and 4D-flow, respectively. Lagrangian coherent structures were used to discriminate KE in the PR. Restrictive RV physiology was defined as end-diastolic forward flow. LV systolic peak KE was lower in rToF, 2.8 ± 1.1 mJ, compared to healthy volunteers, 4.8 ± 1.1 mJ, p < 0.0001. RV diastolic peak KE was higher in rToF (7.7 ± 4.3 mJ vs 3.1 ± 1.3 mJ, p = 0.0001) and the difference most pronounced in patients with non-restrictive RV physiology. KE was primarily located in the PR volume at the time of diastolic peak KE, 64 ± 17%. This is the first study showing disturbed KE in patients with rToF and PR, in both the RV and LV. The role of KE as a potential early marker of ventricular dysfunction to guide intervention needs to be addressed in future studies. • Kinetic energy (KE) reflects ventricular performance • KE is a potential marker of ventricular dysfunction in Fallot patients • KE is disturbed in both ventricles in patients with tetralogy of Fallot • KE contributes to the understanding of the pathophysiology of pulmonary regurgitation • Lagrangian coherent structures enable differentiation of ventricular inflows.

A new route of oxygen isotope exchange in the solid phase: demonstration in CuSO4.5H2O.

PubMed

Danon, Albert; Saig, Avraham; Finkelstein, Yacov; Koresh, Jacob E

2005-11-10

Temperature-programmed desorption mass spectrometry (TPD-MS) measurements on [(18)O]water-enriched copper sulfate pentahydrate (CuSO(4).5H(2)(18)O) reveal an unambiguous occurrence of efficient oxygen isotope exchange between the water of crystallization and the sulfate in its CuSO(4) solid phase. To the best of our knowledge, the occurrence of such an exchange was never observed in a solid phase. The exchange process was observed during the stepwise dehydration (50-300 degrees C) of the compound. Specifically, the exchange promptly occurs somewhere between 160 and 250 degrees C; however, the exact temperature could not be resolved conclusively. It is shown that only the fifth, sulfate-associated, anionic H(2)O molecule participates in the exchange process and that the exchange seems to occur in a preferable fashion with, at the most, one oxygen atom in SO(4). Such an exchange, occurring below 250 degrees C, questions the common conviction of unfeasible oxygen exchange under geothermic conditions. This new oxygen exchange phenomenon is not exclusive to copper sulfate but is unambiguously observed also in other sulfate- and nitrate-containing minerals.

Automating expert role to determine design concept in Kansei Engineering

NASA Astrophysics Data System (ADS)

Lokman, Anitawati Mohd; Haron, Mohammad Bakri Che; Abidin, Siti Zaleha Zainal; Khalid, Noor Elaiza Abd

2016-02-01

Affect has become imperative in product quality. In affective design field, Kansei Engineering (KE) has been recognized as a technology that enables discovery of consumer's emotion and formulation of guide to design products that win consumers in the competitive market. Albeit powerful technology, there is no rule of thumb in its analysis and interpretation process. KE expertise is required to determine sets of related Kansei and the significant concept of emotion. Many research endeavors become handicapped with the limited number of available and accessible KE experts. This work is performed to simulate the role of experts with the use of Natphoric algorithm thus providing sound solution to the complexity and flexibility in KE. The algorithm is designed to learn the process by implementing training datasets taken from previous KE research works. A framework for automated KE is then designed to realize the development of automated KE system. A comparative analysis is performed to determine feasibility of the developed prototype to automate the process. The result shows that the significant Kansei is determined by manual KE implementation and the automated process is highly similar. KE research advocates will benefit this system to automatically determine significant design concepts.

Implementing stakeholder-informed research in the substance abuse treatment sector: strategies used by Connections, a Canadian knowledge translation and exchange project.

PubMed

Henderson, Joanna; Sword, Wendy; Niccols, Alison; Dobbins, Maureen

2014-05-29

Researcher-stakeholder collaboration has been identified as critical to bridging research and health system change. While collaboration models vary, meaningful stakeholder involvement over time ("integrated knowledge translation") is advocated to improve the relevance of research to knowledge users. This short report describes the integrated knowledge translation efforts of Connections, a knowledge translation and exchange project to improve services for women with substance abuse problems and their children, and implementation barriers and facilitators. Strategies of varying intensities were used to engage diverse stakeholders, including policy makers and people with lived experience, and executive directors, program managers, and service providers from Canadian addiction agencies serving women. Barriers to participation included individual (e.g., interest), organizational (e.g., funding), and system level (e.g., lack of centralized stakeholder database) barriers. Similarly, facilitators included individual (e.g., perceived relevance) and organizational (e.g., support) facilitators, as well as initiative characteristics (e.g., multiple involvement opportunities). Despite barriers, Connections' stakeholder-informed research efforts proved essential for developing clinically relevant and feasible processes, measures, and implementation strategies. Stakeholder-researcher collaboration is possible and robust integrated knowledge translation efforts can be productive. Future work should emphasize developing and evaluating a range of strategies to address stakeholders' knowledge translation needs and to facilitate sustained and meaningful involvement in research.

Knowledge Acquisition and Management for the NASA Earth Exchange (NEX)

NASA Astrophysics Data System (ADS)

Votava, P.; Michaelis, A.; Nemani, R. R.

2013-12-01

NASA Earth Exchange (NEX) is a data, computing and knowledge collaboratory that houses NASA satellite, climate and ancillary data where a focused community can come together to share modeling and analysis codes, scientific results, knowledge and expertise on a centralized platform with access to large supercomputing resources. As more and more projects are being executed on NEX, we are increasingly focusing on capturing the knowledge of the NEX users and provide mechanisms for sharing it with the community in order to facilitate reuse and accelerate research. There are many possible knowledge contributions to NEX, it can be a wiki entry on the NEX portal contributed by a developer, information extracted from a publication in an automated way, or a workflow captured during code execution on the supercomputing platform. The goal of the NEX knowledge platform is to capture and organize this information and make it easily accessible to the NEX community and beyond. The knowledge acquisition process consists of three main faucets - data and metadata, workflows and processes, and web-based information. Once the knowledge is acquired, it is processed in a number of ways ranging from custom metadata parsers to entity extraction using natural language processing techniques. The processed information is linked with existing taxonomies and aligned with internal ontology (which heavily reuses number of external ontologies). This forms a knowledge graph that can then be used to improve users' search query results as well as provide additional analytics capabilities to the NEX system. Such a knowledge graph will be an important building block in creating a dynamic knowledge base for the NEX community where knowledge is both generated and easily shared.

Help seeking in older Asian people with dementia in Melbourne: using the Cultural Exchange Model to explore barriers and enablers.

PubMed

Haralambous, Betty; Dow, Briony; Tinney, Jean; Lin, Xiaoping; Blackberry, Irene; Rayner, Victoria; Lee, Sook-Meng; Vrantsidis, Freda; Lautenschlager, Nicola; Logiudice, Dina

2014-03-01

The prevalence of dementia is increasing in Australia. Limited research is available on access to Cognitive Dementia and Memory Services (CDAMS) for people with dementia from Culturally and Linguistically Diverse (CALD) communities. This study aimed to determine the barriers and enablers to accessing CDAMS for people with dementia and their families of Chinese and Vietnamese backgrounds. Consultations with community members, community workers and health professionals were conducted using the "Cultural Exchange Model" framework. For carers, barriers to accessing services included the complexity of the health system, lack of time, travel required to get to services, language barriers, interpreters and lack of knowledge of services. Similarly, community workers and health professionals identified language, interpreters, and community perceptions as key barriers to service access. Strategies to increase knowledge included providing information via radio, printed material and education in community group settings. The "Cultural Exchange Model" enabled engagement with and modification of the approaches to meet the needs of the targeted CALD communities.

Performance Evaluation of a Bedside Cardiac SPECT System

NASA Astrophysics Data System (ADS)

Studenski, Matthew T.; Gilland, David R.; Parker, Jason G.; Hammond, B.; Majewski, Stan; Weisenberger, Andrew G.; Popov, Vladimir

2009-06-01

This paper reports on the initial performance evaluation of a bedside cardiac PET/SPECT system. The system was designed to move within a hospital to image critically-ill patients, for example, those in intensive care unit (ICU) or emergency room settings, who cannot easily be transported to a conventional SPECT or PET facility. The system uses two compact (25 cm times 25 cm) detectors with pixilated NaI crystals and position sensitive PMTs. The performance is evaluated for both 140 keV (Tc-99m) and 511 keV (F-18) emitters with the system operating in single photon counting (SPECT) mode. The imaging performance metrics for both 140 keV and 511 keV included intrinsic energy resolution, spatial resolution (intrinsic, system, and reconstructed SPECT), detection sensitivity, count rate capability, and uniformity. Results demonstrated an intrinsic energy resolution of 31% at 140 keV and 23% at 511 keV, a planar intrinsic spatial resolution of 5.6 mm full width half-maximum (FWHM) at 140 keV and 6.3 mm FWHM at 511 keV, and a sensitivity of 4.15 countsmiddotmuCi-1 ldr s-1 at 140 keV and 0.67 counts ldr muCi-1 ldr s-1 at 511 keV. To further the study, a SPECT acquisition using a dynamic cardiac phantom was performed, and the resulting reconstructed images are presented.

Performance Evaluation of a Bedside Cardiac SPECT System

DOE Office of Scientific and Technical Information (OSTI.GOV)

M.T. Studenski, D.R. Gilland, J.G. Parker, B. Hammond, S. Majewski, A.G. Weisenberger, V. Popov

This paper reports on the initial performance evaluation of a bedside cardiac PET/SPECT system. The system was designed to move within a hospital to image critically-ill patients, for example, those in intensive care unit (ICU) or emergency room settings, who cannot easily be transported to a conventional SPECT or PET facility. The system uses two compact (25 cm times 25 cm) detectors with pixilated NaI crystals and position sensitive PMTs. The performance is evaluated for both 140 keV (Tc-99m) and 511 keV (F-18) emitters with the system operating in single photon counting (SPECT) mode. The imaging performance metrics for bothmore » 140 keV and 511 keV included intrinsic energy resolution, spatial resolution (intrinsic, system, and reconstructed SPECT), detection sensitivity, count rate capability, and uniformity. Results demonstrated an intrinsic energy resolution of 31% at 140 keV and 23% at 511 keV, a planar intrinsic spatial resolution of 5.6 mm full width half-maximum (FWHM) at 140 keV and 6.3 mm FWHM at 511 keV, and a sensitivity of 4.15 countsmiddotmuCi-1 ldr s-1 at 140 keV and 0.67 counts ldr muCi-1 ldr s-1 at 511 keV. To further the study, a SPECT acquisition using a dynamic cardiac phantom was performed, and the resulting reconstructed images are presented.« less

105KE Basin Area Radiation Monitor System (ARMS) Acceptance Test Procedure

DOE Office of Scientific and Technical Information (OSTI.GOV)

KINKEL, C.C.

1999-12-14

This procedure is intended for the Area Radiation Monitoring System, ARMS, that is replacing the existing Programmable Input-Output Processing System, PIOPS, radiation monitoring system in the 105KE basin. The new system will be referred to as the 105KE ARMS, 105KE Area Radiation Monitoring System. This ATP will ensure calibration integrity of the 105KE radiation detector loops. Also, this ATP will test and document the display, printing, alarm output, alarm acknowledgement, upscale check, and security functions. This ATP test is to be performed after completion of the 105KE ARMS installation. The alarm outputs of the 105KE ARMS will be connected tomore » the basin detector alarms, basin annunciator system, and security Alarm Monitoring System, AMS, located in the 200 area Central Alarm Station (CAS).« less

Legume-rhizobia signal exchange: promiscuity and environmental effects.

PubMed

Lira, Mario A; Nascimento, Luciana R S; Fracetto, Giselle G M

2015-01-01

Although signal exchange between legumes and their rhizobia is among the best-known examples of this biological process, most of the more characterized data comes from just a few legume species and environmental stresses. Although a relative wealth of information is available for some model legumes and some of the major pulses such as soybean, little is known about tropical legumes. This relative disparity in current knowledge is also apparent in the research on the effects of environmental stress on signal exchange; cool-climate stresses, such as low-soil temperature, comprise a relatively large body of research, whereas high-temperature stresses and drought are not nearly as well understood. Both tropical legumes and their environmental stress-induced effects are increasingly important due to global population growth (the demand for protein), climate change (increasing temperatures and more extreme climate behavior), and urbanization (and thus heavy metals). This knowledge gap for both legumes and their environmental stresses is compounded because whereas most temperate legume-rhizobia symbioses are relatively specific and cultivated under relatively stable environments, the converse is true for tropical legumes, which tend to be promiscuous, and grow in highly variable conditions. This review will clarify some of this missing information and highlight fields in which further research would benefit our current knowledge.

Talk, trust and time: a longitudinal study evaluating knowledge translation and exchange processes for research on violence against women

PubMed Central

2011-01-01

Background Violence against women (VAW) is a major public health problem. Translation of VAW research to policy and practice is an area that remains understudied, but provides the opportunity to examine knowledge translation and exchange (KTE) processes in a complex, multi-stakeholder context. In a series of studies including two randomized trials, the McMaster University VAW Research Program studied one key research gap: evidence about the effectiveness of screening women for exposure to intimate partner violence. This project developed and evaluated KTE strategies to share research findings with policymakers, health and community service providers, and women's advocates. Methods A longitudinal cross-sectional design, applying concurrent mixed data collection methods (surveys, interviews, and focus groups), was used to evaluate the utility of specific KTE strategies, including a series of workshops and a day-long Family Violence Knowledge Exchange Forum, on research sharing, uptake, and use. Results Participants valued the opportunity to meet with researchers, provide feedback on key messages, and make personal connections with other stakeholders. A number of factors specific to the knowledge itself, stakeholders' contexts, and the nature of the knowledge gap being addressed influenced the uptake, sharing, and use of the research. The types of knowledge use changed across time, and were specifically related to both the types of decisions being made, and to stage of decision making; most reported use was conceptual or symbolic, with few examples of instrumental use. Participants did report actively sharing the research findings with their own networks. Further examination of these second-order knowledge-sharing processes is required, including development of appropriate methods and measures for its assessment. Some participants reported that they would not use the research evidence in their decision making when it contradicted professional experiences, while others used it to support apparently contradictory positions. The online wiki-based 'community of interest' requested by participants was not used. Conclusions Mobilizing knowledge in the area of VAW practice and policy is complex and resource-intensive, and must acknowledge and respect the values of identified knowledge users, while balancing the objectivity of the research and researchers. This paper provides important lessons learned about these processes, including attending to the potential unintended consequences of knowledge sharing. PMID:21896170

Talk, trust and time: a longitudinal study evaluating knowledge translation and exchange processes for research on violence against women.

PubMed

Wathen, C Nadine; Sibbald, Shannon L; Jack, Susan M; Macmillan, Harriet L

2011-09-06

Violence against women (VAW) is a major public health problem. Translation of VAW research to policy and practice is an area that remains understudied, but provides the opportunity to examine knowledge translation and exchange (KTE) processes in a complex, multi-stakeholder context. In a series of studies including two randomized trials, the McMaster University VAW Research Program studied one key research gap: evidence about the effectiveness of screening women for exposure to intimate partner violence. This project developed and evaluated KTE strategies to share research findings with policymakers, health and community service providers, and women's advocates. A longitudinal cross-sectional design, applying concurrent mixed data collection methods (surveys, interviews, and focus groups), was used to evaluate the utility of specific KTE strategies, including a series of workshops and a day-long Family Violence Knowledge Exchange Forum, on research sharing, uptake, and use. Participants valued the opportunity to meet with researchers, provide feedback on key messages, and make personal connections with other stakeholders. A number of factors specific to the knowledge itself, stakeholders' contexts, and the nature of the knowledge gap being addressed influenced the uptake, sharing, and use of the research. The types of knowledge use changed across time, and were specifically related to both the types of decisions being made, and to stage of decision making; most reported use was conceptual or symbolic, with few examples of instrumental use. Participants did report actively sharing the research findings with their own networks. Further examination of these second-order knowledge-sharing processes is required, including development of appropriate methods and measures for its assessment. Some participants reported that they would not use the research evidence in their decision making when it contradicted professional experiences, while others used it to support apparently contradictory positions. The online wiki-based 'community of interest' requested by participants was not used. Mobilizing knowledge in the area of VAW practice and policy is complex and resource-intensive, and must acknowledge and respect the values of identified knowledge users, while balancing the objectivity of the research and researchers. This paper provides important lessons learned about these processes, including attending to the potential unintended consequences of knowledge sharing.

Advances in Small Pixel TES-Based X-Ray Microcalorimeter Arrays for Solar Physics and Astrophysics

NASA Technical Reports Server (NTRS)

Bandler, S. R.; Adams, J. S.; Bailey, C. N.; Busch, S. E.; Chervenak, J. A.; Eckart, M. E.; Ewin, A. E.; Finkbeiner, F. M.; Kelley, R. L.; Kelly, D. P.;

Stakeholder Engagement Opportunities in Systematic Reviews: Knowledge Transfer for Policy and Practice

ERIC Educational Resources Information Center

Keown, Kiera; Van Eerd, Dwayne; Irvin, Emma

2008-01-01

Knowledge transfer and exchange is the process of increasing the awareness and use of research evidence in policy or practice decision making by nonresearch audiences or stakeholders. One way to accomplish this end is through ongoing interaction between researchers and interested nonresearch audiences, which provides an opportunity for the two…

"That Happened to Me Too": Young People's Informal Knowledge of Diverse Genders and Sexualities

ERIC Educational Resources Information Center

Byron, Paul; Hunt, Jessie

2017-01-01

This paper explores how young people of diverse genders and sexualities share information about sex, sexualities and genders. Formal approaches to education often fail to consider young people's communication and information exchange practices, including the circulation of peer knowledge through social media. In the wake of recent Australian…

Work Experience Program at a Metropolitan Paediatric Hospital: Assisting Rural and Metropolitan Allied Health Professionals Exchange Clinical Skills.

ERIC Educational Resources Information Center

Parkin, Ann E.; McMahon, Sandra; Upfield, Nancy; Copley, Jodie; Hollands, Karen

2001-01-01

A clinical experience program provided 29 rural Australian allied health professionals with experience in pediatric clinical areas and opportunities to share clinical knowledge and develop networks with metropolitan peers. Questionnaires and focus groups indicated that networking, clinical skills, knowledge, confidence, and awareness of rural…

Designing Play for Dark Times

ERIC Educational Resources Information Center

Yamada-Rice, Dylan

2017-01-01

This article reports on a knowledge-exchange network project that had the core aim of informing the development of a video game for hospitalized children. In order to do this, it brought together hospital play specialists, academics and representatives from the digital games industry to co-produce knowledge that could be used in the future…

School Knowledge in Talk and Writing: Taking "When Learners Know" Seriously

ERIC Educational Resources Information Center

Freebody, Peter

2013-01-01

This paper expands on the view that the documentation of the ways in which teachers and students produce definitions of such operational matters as "reading", "writing", "learning" and "knowledge" in classrooms is discoverable in the details of the speech exchange systems in those sites. The paper provides a brief introduction to applied…

Bi-directional exchange of ammonia in a pine forest ecosystem - a model sensitivity analysis

NASA Astrophysics Data System (ADS)

Moravek, Alexander; Hrdina, Amy; Murphy, Jennifer

2016-04-01

Ammonia (NH3) is a key component in the global nitrogen cycle and of great importance for atmospheric chemistry, neutralizing atmospheric acids and leading to the formation of aerosol particles. For understanding the role of NH3 in both natural and anthropogenically influenced environments, the knowledge of processes regulating its exchange between ecosystems and the atmosphere is essential. A two-layer canopy compensation point model is used to evaluate the NH3 exchange in a pine forest in the Colorado Rocky Mountains. The net flux comprises the NH3 exchange of leaf stomata, its deposition to leaf cuticles and exchange with the forest ground. As key parameters the model uses in-canopy NH3 mixing ratios as well as leaf and soil emission potentials measured at the site in summer 2015. A sensitivity analysis is performed to evaluate the major exchange pathways as well as the model's constraints. In addition, the NH3 exchange is examined for an extended range of environmental conditions, such as droughts or varying concentrations of atmospheric pollutants, in order to investigate their influence on the overall net exchange.

Project Teen-Ager - A Skills Exchange Program: High School Students Volunteering with the Elderly in a Rural Community.

ERIC Educational Resources Information Center

Morris, Judson H., Jr.

Designed to improve self esteem and quality of life for rural adolescents and elderly, Project Teen-Ager enables these groups to exchange knowledge and skills for their mutual benefit. Initial sponsors of the program were Manning High School and South Carolina Community Long Term Care, a state agency for elderly/disabled persons who need help to…

OVII and Temperature Limits on the Local Hot Bubble

NASA Astrophysics Data System (ADS)

Pirtle, Robert; Petre, N.; McCammon, D.; Morgan, K.; Sauter, P.; Clavadetscher, K.; Fujimoto, R.; Hagihara, T.; Masui, K.; Mitsuda, K.; Takei, Y.; Wang, Q. D.; Yamasaki, N. Y.; Yao, Y.; Yoshino, T.

2013-01-01

The observed ¼-keV (ROSAT R12 band) X-ray background originates largely in a region of hot ionized gas roughly 100 pc in extent surrounding the Sun known as the Local Hot Bubble (LHB). The observed flux is quite uniform at low latitudes (|b| < 30°), but there a several large areas at intermediate and high latitudes that are enhanced by factors of 2 - 3. Charge exchange between highly charged ions in the Solar wind and interstellar neutral H and He moving through interplanetary space might provide a very roughly isotropic contribution about equal to the low- latitude flux (Koutroumpa et al. 2008), but cannot produce the enhancements. Correlations with the interstellar absorbing column show that some of these bright regions are apparently due to clumps of hot gas in the Galactic halo, while many of them show no correlation and must be due to extensions of the LHB (Kuntz & Snowden 2000, Bellm & Vaillancourt 2005). Global fits of simple plasma emission spectra give temperatures near 1.0 x 106 K for both LHB and halo emission, but the possibility of a substantial contamination by charge exchange could distort this result in unknown ways. Thermal excitation of O VII is strongly temperature dependent in this range, so we have tried to correlate O VII fluxes measured with Suzaku with variations in ¼-keV intensity from the ROSAT R12 band map to determine the temperature. We take eleven O VII intensity measurements from Yoshino et al. (2009), one from Masui et al. (2009), and an additional eighteen from archival Suzaku pointings and correlate these with the R12 band local and halo intensities as separated by Kunzt & Snowden (2000). The lack of detectable correlation in both cases strongly limits any O VII production by the material producing the enhancements, and upper limits to the temperatures are set. This work was supported in part by the National Science Foundation's REU program through NSF Award AST-1004881 and by NASA grant NNX09AF09G. *present address: Department of Physics, Lewis & Clark College, Portland, OR. This work was supported in part by the National Science Foundation's REU program through NSF Award AST-1004881.

The Solar Wind Charge-Transfer X-Ray Emission in the 1/4 keV Energy Range: Inferences on Local Bubble Hot Gas at Low Z

NASA Astrophysics Data System (ADS)

Koutroumpa, D.; Lallement, R.; Raymond, J. C.; Kharchenko, V.

2009-05-01

We present calculations of the heliospheric solar wind charge-exchange (SWCX) emission spectra and the resulting contributions of this diffuse background in the ROSAT 1/4 keV bands. We compare our results with the soft X-ray background (SXRB) emission detected in front of 378 identified shadowing regions during the ROSAT All-Sky Survey. This foreground component is principally attributed to the hot gas of the so-called Local Bubble (LB), an irregularly shaped cavity of ~50-150 pc around the Sun, which is supposed to contain ~106 K plasma. Our results suggest that the SWCX emission from the heliosphere is bright enough to account for most of the foreground emission toward the majority of low galactic latitude directions, where the LB is the least extended. On the other hand, in a large part of directions with galactic latitude above 30°, the heliospheric SWCX intensity is significantly smaller than the measured one. However, the SWCX R2/R1 band ratio differs slightly from the data in the galactic center direction, and more significantly in the galactic anticentre direction where the observed ratio is the smallest. Assuming that both SWCX and hot gas emission are present and their relative contributions vary with direction, we tested a series of thermal plasma spectra for temperatures ranging from 10 5 to 10 6.5 K and searched for a combination of SWCX spectra and thermal emission matching the observed intensities and band ratios, while simultaneously being compatible with O VI emission measurements. In the frame of collisional equilibrium models and for solar abundances, the range we derive for hot gas temperature and emission measure cannot reproduce the Wisconsin C/B band ratio. This implies that accounting for SWCX contamination does not remove these known disagreements between data and classical hot gas models. We emphasize the need for additional atomic data, describing consistently EUV and X-ray photon spectra of the charge-exchange emission of heavier solar wind ions.

Low knowledge and perceived Hepatitis C risk despite high risk behaviour among injection drug users in Kathmandu, Nepal.

PubMed

Loewinger, Gabriel; Sharma, Bishnu; Karki, Deepak Kumar; Khatiwoda, Prasana; Kainee, Sher; Poudel, Krishna C

2016-07-01

In Nepal, prevalence of Hepatitis C (HCV) among injecting drug users (IDUs) has been measured at 50% and knowledge of the virus is low. Rehabilitation and harm reduction attendees constitute populations to whom health care providers can deliver services. As such, characterizing their drug use and risk profiles is important for developing targeted service delivery. We measured drug use and risk patterns of IDUs participating in residential rehabilitation as well as those contacted through needle exchanges to identify correlates of drug use frequency, risky injection practices as well as HCV testing, knowledge and perceived risk. We collected cross-sectional data from one-on-one structured interviews of IDUs contacted through needle-exchange outreach workers (n=202) and those attending rehabilitation centres (behaviour immediately prior to joining rehabilitation) (n=167). Roughly half of participants reported injecting at least 30 times in the past 30 days and individuals with previous residential rehabilitation experience reported frequent injection far more than those without it. About one in fourteen respondents reported past week risky injection practices. Participants were over three times as likely to report risky injection if they consumed alcohol daily (17.2%) than if they did not (5.0%) (p=0.002). Those who reported injecting daily reported risky injection practices (11.9%) significantly more than non-daily injectors (1.8%) (p<0.001). Respondents reported high HCV infection rates, low perceived risk, testing history and knowledge. HCV knowledge was not associated with differences in risky injecting. Treatment centres should highlight the link between heavy drinking, frequent injection and risky injecting practices. The link between rehabilitation attendance and frequent injection may suggest IDUs with more severe use patterns are more likely to attend rehabilitation. Rehabilitation centres and needle exchanges should provide testing and education for HCV. Education alone may not be sufficient to initiate change since knowledge did not predict lower risk. Copyright © 2016 Elsevier B.V. All rights reserved.

Open exchange of scientific knowledge and European copyright: The case of biodiversity information

PubMed Central

Egloff, Willi; Patterson, David J.; Agosti, Donat; Hagedorn, Gregor

2014-01-01

Abstract Background. The 7th Framework Programme for Research and Technological Development is helping the European Union to prepare for an integrative system for intelligent management of biodiversity knowledge. The infrastructure that is envisaged and that will be further developed within the Programme “Horizon 2020” aims to provide open and free access to taxonomic information to anyone with a requirement for biodiversity data, without the need for individual consent of other persons or institutions. Open and free access to information will foster the re-use and improve the quality of data, will accelerate research, and will promote new types of research. Progress towards the goal of free and open access to content is hampered by numerous technical, economic, sociological, legal, and other factors. The present article addresses barriers to the open exchange of biodiversity knowledge that arise from European laws, in particular European legislation on copyright and database protection rights. We present a legal point of view as to what will be needed to bring distributed information together and facilitate its re-use by data mining, integration into semantic knowledge systems, and similar techniques. We address exceptions and limitations of copyright or database protection within Europe, and we point to the importance of data use agreements. We illustrate how exceptions and limitations have been transformed into national legislations within some European states to create inconsistencies that impede access to biodiversity information. Conclusions. The legal situation within the EU is unsatisfactory because there are inconsistencies among states that hamper the deployment of an open biodiversity knowledge management system. Scientists within the EU who work with copyright protected works or with protected databases have to be aware of regulations that vary from country to country. This is a major stumbling block to international collaboration and is an impediment to the open exchange of biodiversity knowledge. Such differences should be removed by unifying exceptions and limitations for research purposes in a binding, Europe-wide regulation. PMID:25009418

The Study on Collaborative Manufacturing Platform Based on Agent

NASA Astrophysics Data System (ADS)

Zhang, Xiao-yan; Qu, Zheng-geng

To fulfill the trends of knowledge-intensive in collaborative manufacturing development, we have described multi agent architecture supporting knowledge-based platform of collaborative manufacturing development platform. In virtue of wrapper service and communication capacity agents provided, the proposed architecture facilitates organization and collaboration of multi-disciplinary individuals and tools. By effectively supporting the formal representation, capture, retrieval and reuse of manufacturing knowledge, the generalized knowledge repository based on ontology library enable engineers to meaningfully exchange information and pass knowledge across boundaries. Intelligent agent technology increases traditional KBE systems efficiency and interoperability and provides comprehensive design environments for engineers.

Increase Productivity Through Knowledge Management

NASA Astrophysics Data System (ADS)

Gavrikova, N. A.; Dolgih, I. N.; Dyrina, E. N.

2016-04-01

Increase in competition level requires companies to improve the efficiency of work force use characterized by labor productivity. Professional knowledge of staff and its experience play the key role in it. The results of Extrusion Line operator’s working time analysis are performed in this article. The analysis revealed that the reasons of working time ineffective use connected with inadequate information exchange and knowledge management in the company. Authors suggest the way to solve this problem: the main sources of knowledge in engineering enterprise have been defined, the conditions of success and the stages of knowledge management control have been stated.

Compound semiconductor detectors for X-ray astronomy: Spectroscopic measurements and material characterization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bavdaz, M.; Kraft, S.; Peacock, A.

1998-12-31

The use of some specific compound semiconductors in the fabrication of high energy X-ray detectors shows significant potential for X-ray astrophysics space missions. The authors are currently investigating three high purity crystals--CdZnTe, GaAs and TlBr--as the basis for future hard X-ray detectors (above 10 keV). In this paper the authors present the first results on CdZnTe and GaAs based detectors and evaluate the factors currently still constraining the performance. Energy resolutions (FWHM) of 0.9 keV and 1.1 keV at 14 keV and 60 keV, respectively, have been obtained with an epitaxial GaAs detector, while 0.7 keV and 1.5 keV FWHMmore » were measured at the same energies with a CdZnTe detector. Based on these results it is clear, that the next generation of X-ray astrophysics missions now in the planning phase may well consider extending the photon energy range up to {approximately} 100 keV by use of efficient detectors with reasonable spectroscopic capabilities.« less

Virtual monochromatic imaging in dual-source and dual-energy CT for visualization of acute ischemic stroke

NASA Astrophysics Data System (ADS)

Hara, Hidetake; Muraishi, Hiroshi; Matsuzawa, Hiroki; Inoue, Toshiyuki; Nakajima, Yasuo; Satoh, Hitoshi; Abe, Shinji

2015-07-01

We have recently developed a phantom that simulates acute ischemic stroke. We attempted to visualize an acute-stage cerebral infarction by using dual-energy Computed tomography (DECT) to obtain virtual monochromatic images of this phantom. Virtual monochromatic images were created by using DECT voltages from 40 to 100 keV in steps of 10 keV and from 60 to 80 keV in steps of 1 keV, under three conditions of the tube voltage with thin (Sn) filters. Calculation of the CNR values allowed us to evaluate the visualization of acute-stage cerebral infarction. The CNR value of a virtual monochromatic image was the highest at 68 keV under 80 kV / Sn 140 kV, at 72 keV under 100 kV / Sn 140 kV, and at 67 keV under 140 kV / 80 kV. The CNR values of virtual monochromatic images at voltages between 65 and 75 keV were significantly higher than those obtained for all other created images. Therefore, the optimal conditions for visualizing acute ischemic stroke were achievable.

Performance of a miniature mechanically cooled HPGe gamma-spectrometer for space applications

NASA Astrophysics Data System (ADS)

Kondratjev, V.; Pchelintsev, A.; Jakovlevs, O.; Sokolov, A.; Gostilo, V.; Owens, A.

2018-01-01

We report on the development of a miniaturized HPGe gamma-spectrometer for space applications. The instrument is designed around a 158 cm3 intrinsically pure Ge crystal in the closed-end coaxial configuration, cooled by a Thales RM3 miniature Stirling cycle electric cooler. To compensate the noise induced by the mechanical cooler the digital procession of the spectrometric signals with low frequency reject filter (LFR) is applied. The complete spectrometer assembly has a mass of 3.1 kg and consumes less than 10 W under working operation. The spectrometer was tested under a number of operating conditions in a specially designed chamber, which simulates the space environment. With the mechanical cooler switched off, FWHM energy resolutions of 1.5 keV and 2.2 keV were obtained at 122 keV and 1333 keV, respectively, at the nominal operating temperature of 90 K. When the cooler was switched on the energy resolutions degraded to 2.5 keV and 4 keV respectively. However, with the LFR filter switched in, the resolutions improved significantly to 1.8 keV and 2.4 keV.

Ethics, Collaboration, and Presentation Methods for Local and Traditional Knowledge for Understanding Arctic Change

NASA Astrophysics Data System (ADS)

Parsons, M. A.; Gearheard, S.; McNeave, C.

2009-12-01

Local and traditional knowledge (LTK) provides rich information about the Arctic environment at spatial and temporal scales that scientific knowledge often does not have access to (e.g. localized observations of fine-scale ecological change potentially from many different communities, or local sea ice and conditions prior to 1950s ice charts and 1970s satellite records). Community-based observations and monitoring are an opportunity for Arctic residents to provide ‘frontline’ observations and measurements that are an early warning system for Arctic change. The Exchange for Local Observations and Knowledge of the Arctic (ELOKA) was established in response to the growing number of community-based and community-oriented research and observation projects in the Arctic. ELOKA provides data management and user support to facilitate the collection, preservation, exchange, and use of local observations and knowledge. Managing these data presents unique ethical challenges in terms of appropriate use of rare human knowledge and ensuring that knowledge is not lost from the local communities and not exploited in ways antithetical to community culture and desires. Local Arctic residents must be engaged as true collaborative partners while respecting their perspectives, which may vary substantially from a western science perspective. At the same time, we seek to derive scientific meaning from the local knowledge that can be used in conjunction with quantitative science data. This creates new challenges in terms of data presentation, knowledge representations, and basic issues of metadata. This presentation reviews these challenges, some initial approaches to addressing them, and overall lessons learned and future directions.

On-ground calibration of the Hitomi Hard X-ray Telescopes

NASA Astrophysics Data System (ADS)

Mori, Hideyuki; Miyazawa, Takuya; Awaki, Hisamitsu; Matsumoto, Hironori; Babazaki, Yasunori; Bandai, Ayako; Demoto, Tadatsugu; Furuzawa, Akihiro; Haba, Yoshito; Hayashi, Takayuki; Iizuka, Ryo; Ishibashi, Kazunori; Ishida, Manabu; Ishida, Naoki; Itoh, Masayuki; Iwase, Toshihiro; Kato, Hiroyoshi; Kobayashi, Hiroaki; Kosaka, Tatsuro; Kunieda, Hideyo; Kurashima, Shou; Kurihara, Daichi; Kuroda, Yuuji; Maeda, Yoshitomo; Meshino, Yoshifumi; Mitsuishi, Ikuyuki; Miyata, Yuusuke; Nagano, Housei; Namba, Yoshiharu; Ogasaka, Yasushi; Ogi, Keiji; Okajima, Takashi; Saji, Shigetaka; Shimasaki, Fumiya; Sato, Takuro; Sato, Toshiki; Shima, Naotsugu; Sugita, Satoshi; Suzuki, Yoshio; Tachibana, Kenji; Tachibana, Sasagu; Takizawa, Shun'ya; Tamura, Keisuke; Tawara, Yuzuru; Tomikawa, Kazuki; Torii, Tatsuharu; Uesugi, Kentaro; Yamashita, Koujun; Yamauchi, Shigeo

2018-01-01

We present x-ray characteristics of the Hard X-ray Telescopes (HXTs) on board the Hitomi (ASTRO-H) satellite. Measurements were conducted at the SPring-8 BL20B2 beamline and the ISAS/JAXA 27-m beamline. The angular resolution defined by a half-power diameter was 1.9‧ (HXT-1) and 2.1‧ (HXT-2) at 8 keV, 1.9‧ at 30 keV, and 1.8‧ at 50 keV. The effective area was found to be 620 cm2 at 8 keV, 178 cm2 at 30 keV, and 82 cm2 at 50 keV per mirror module. Although the angular resolutions were slightly worse than the requirement (1.7‧), the effective areas sufficiently exceeded the requirements of 150 cm2 at 30 keV and 55 cm2 at 50 keV. The off-axis measurements of the effective areas resulted in the field of view being 6.1‧ at 50 keV, 7.7‧ at 30 keV, and 9.7‧ at 8 keV in diameter. We confirmed that the main component of the stray x-ray light was significantly reduced by mounting the precollimator as designed. Detailed analysis of the data revealed that the angular resolution was degraded mainly by figure errors of mirror foils, and the angular resolution is completely explained by the figure errors, positioning errors of the foils, and conical approximation of the foil shape. We found that the effective areas were ˜80% of the designed values below 40 keV, whereas they steeply decline above 40 keV and become only ˜50%. We investigated this abrupt decline and found that neither the error of the multilayer design nor the errors of the incident angles induced by the positioning errors of the foils can be the cause. The reflection profile of each foil pair from the defocused image strongly suggests that the figure errors of the foils probably bring about the reduction in the effective areas at higher energies.

Global microbial commons: institutional challenges for the global exchange and distribution of microorganisms in the life sciences.

PubMed

Dedeurwaerdere, Tom

2010-01-01

Exchanges of microorganisms between culture collections, laboratories and researchers worldwide have historically occurred in an informal way. These informal exchanges have facilitated research activities, and, as a consequence, our knowledge and exploitation of microbial resources have advanced rapidly. During the last decades of the twentieth century, the increasing economic importance of biotechnology and the introduction of new legislation concerning the use of and access to biological resources has subjected exchanges of genetic resources to greater controls. Their access and distribution are more strictly regulated and, therefore, exchanges are becoming more and more formalized. This paper analyzes one of the main drivers of the movement toward more formal worldwide exchange regimes, which is increasing global interdependency of access to genetic resources. Its main finding is that formalization of exchange practices as such is not necessarily leading to more restrictive licensing conditions. The goal of further formalization and harmonization of institutional frameworks should therefore be to provide the broadest possible access to essential research materials (within the constraints set by biosecurity and quality management requirements), while maximizing the reciprocity benefits of access and exchange (which motivate the exchange practices to start with). (c) 2010 Elsevier Masson SAS. All rights reserved.

International nursing exchange and collaboration with China: a perspective from the South and the East.

PubMed

Xu, Yu

2012-01-01

There are an imbalanced world power relationships and international knowledge system, as well as cultural differences across nations. Based on the author's international experiences, this article describes the needs and motivations of international exchange and collaboration in nursing from the perspective of both China and Western countries, examines the ethical and cultural issues involved, and suggests winning strategies. Western educators and scholars must keep these issues and strategies in mind in order to build a productive, mutually beneficial, and sustainable international exchanges and collaboration. © 2012 Wiley Periodicals, Inc.

Fostering Practical Young Engineers through Mutual Exchange Internship Program between Japan and China

NASA Astrophysics Data System (ADS)

Suda, Yoshiaki; Kawasaki, Hiroharu; Shigematsu, Toshinobu; Ono, Bunji; Watanabe, Tetsuya; Morishita, Koji; Inoue, Masahiro

Sasebo National College of Technology started a mutual exchange internship program in 2005 in partnership with Xiamen University of Technology. The aim of this program is to educate and train young Japanese engineers who can apply their knowledge and skills fully to their work in the factories in China. This program also aims to educate and train young Chinese engineers who will acquire not only technological knowledge and skills but also an understanding of the organizational structure and cultural background of Japanese companies. By deepening mutual understanding between Japan and China through this program, young Japanese and Chinese engineers can work toward their common goal of economic prosperity in their respective countries, while building partnerships based on mutual trust and respect.

Enhancing fire science exchange: The Joint Fire Science Program's National Network of Knowledge Exchange Consortia

Treesearch

Vita Wright; Crystal Kolden; Todd Kipfer; Kristine Lee; Adrian Leighton; Jim Riddering; Leana Schelvan

2011-01-01

The Northern Rocky Mountain region is one of the most fire-prone regions in the United States. With a history of large fires that have shaped national policy, including the fires of 1910 and 2000 in Idaho and Montana and the Yellowstone fires of 1988, this region is projected to have many large severe fires in the future. Communication about fire science needs and...

A Proposed Model for Authenticating Knowledge Transfer in Online Discussion Forums

ERIC Educational Resources Information Center

Tucker, Jan P.; YoungGonzaga, Stephanie; Krause, Jaclyn

2014-01-01

Discussion forums are often utilized in the online classroom to build a sense of community, encourage collaboration and exchange, and measure time on task. A review of the literature revealed that there is little research that examines the role of the online discussion forum as a mechanism for knowledge transfer. Researchers reviewed 21 course…

An Exploration of School Counselors' Knowledge Sharing Practices Using Diffusion of Innovation Theory, Social Exchange Theory, and Theory of Reasoned Action

ERIC Educational Resources Information Center

Shipp, Adria E.

2010-01-01

School counselors are expected to be advocates, collaborators, consultants, and leaders in their work with students, families, administrators, school staff, and community based stakeholders (ASCA, 2005; Shoffner & Briggs, 2001; Rowley, 2000). Underlying these expectations is the belief that school counselors are knowledgeable in the areas that…

Teacher Education for World English Speaking Pre-Service Teachers: Making Transnational Knowledge Exchange for Mutual Learning

ERIC Educational Resources Information Center

Singh, Michael; Han, Jinghe

2010-01-01

Pre-service teachers are taught that the funds of knowledge their students bring to school provide intellectual resources to be engaged through productive pedagogies. Teacher education may assist and/or hinder World English Speaking (WES) pre-service teachers in gaining access to the teaching profession by doing likewise. The interpretative case…

Blogs: Enhancing Links in a Professional Learning Community of Science and Mathematics Teachers

ERIC Educational Resources Information Center

Loving, Cathleen C.; Schroeder, Carolyn; Kang, Rui; Shimek, Christine; Herbert, Bruce

2007-01-01

Anyone who can access the Internet can be part of the knowledge-access, knowledge-building, information-exchanging culture, regardless of location. The research presented in this article is about blogs and their use in a new teacher professional development project. Weblogs were first named and described in 1997 by Jorn Barger (Blood, 2000) and…

78 FR 26828 - Self-Regulatory Organizations; Chicago Board Options Exchange, Incorporated; Order Granting...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-08

... simultaneously holding and working a customer order in that same stock. No-Knowledge Exception \\14\\ \\14\\ See... prevent the proprietary trading unit from obtaining knowledge of the customer orders that are held at a... Rule Change, as Modified by Amendment No. 1, Relating to Trading Ahead of Customer Orders and Best...

High Resolution, Non-Dispersive X-Ray Calorimeter Spectrometers on EBITs and Orbiting Observatories

NASA Technical Reports Server (NTRS)

Porter, Frederick S.

2010-01-01

X-ray spectroscopy is the primary tool for performing atomic physics with Electron beam ion trap (EBITs). X-ray instruments have generally fallen into two general categories, 1) dispersive instruments with very high spectral resolving powers but limited spectral range, limited count rates, and require an entrance slit, generally, for EBITs, defined by the electron beam itself, and 2) non-dispersive solid-state detectors with much lower spectral resolving powers but that have a broad dynamic range, high count rate ability and do not require a slit. Both of these approaches have compromises that limit the type and efficiency of measurements that can be performed. In 1984 NASA initiated a program to produce a non-dispersive instrument with high spectral resolving power for x-ray astrophysics based on the cryogenic x-ray calorimeter. This program produced the XRS non-dispersive spectrometers on the Astro-E, Astro-E2 (Suzaku) orbiting observatories, the SXS instrument on the Astro-H observatory, and the planned XMS instrument on the International X-ray Observatory. Complimenting these spaceflight programs, a permanent high-resolution x-ray calorimeter spectrometer, the XRS/EBIT, was installed on the LLNL EBIT in 2000. This unique instrument was upgraded to a spectral resolving power of 1000 at 6 keV in 2003 and replaced by a nearly autonomous production-class spectrometer, the EBIT Calorimeter Spectrometer (ECS), in 2007. The ECS spectrometer has a simultaneous bandpass from 0.07 to over 100 keV with a spectral resolving power of 1300 at 6 keV with unit quantum efficiency, and 1900 at 60 keV with a quantum efficiency of 30%. X-ray calorimeters are event based, single photon spectrometers with event time tagging to better than 10 us. We are currently developing a follow-on instrument based on a newer generation of x-ray calorimeters with a spectral resolving power of 3000 at 6 keV, and improved timing and measurement cadence. The unique capabilities of the x-ray calorimeter spectrometer, coupled with higher spectral resolution dispersive spectrometers to resolve line blends, has enabled many science investigations, to date mostly in our x-ray laboratory astrophysics program. These include measurements of absolute cross sections for Land K shell emission from Fe and Ni, charge exchange measurements in many astrophysically abundant elements, lifetime measurements, line ratios, and wavelength measurements. In addition, we have performed many additional measurements in nuclear physics, and in support of diagnostics for laser fusion, for example. In this presentation we will give a detailed overview of x-ray calorimeter instruments in general and in our EBIT laboratory astrophysics program in particular. We will also discuss the science yield of our measurements at EBIT over the last decade) prospects for future science enabled by the current generation of spectrometers and that will be expanded in the near future by the next generation of spectrometers starting in 2611.

Social network analysis of multi-stakeholder platforms in agricultural research for development: Opportunities and constraints for innovation and scaling.

PubMed

Hermans, Frans; Sartas, Murat; van Schagen, Boudy; van Asten, Piet; Schut, Marc

2017-01-01

Multi-stakeholder platforms (MSPs) are seen as a promising vehicle to achieve agricultural development impacts. By increasing collaboration, exchange of knowledge and influence mediation among farmers, researchers and other stakeholders, MSPs supposedly enhance their 'capacity to innovate' and contribute to the 'scaling of innovations'. The objective of this paper is to explore the capacity to innovate and scaling potential of three MSPs in Burundi, Rwanda and the South Kivu province located in the eastern part of Democratic Republic of Congo (DRC). In order to do this, we apply Social Network Analysis and Exponential Random Graph Modelling (ERGM) to investigate the structural properties of the collaborative, knowledge exchange and influence networks of these MSPs and compared them against value propositions derived from the innovation network literature. Results demonstrate a number of mismatches between collaboration, knowledge exchange and influence networks for effective innovation and scaling processes in all three countries: NGOs and private sector are respectively over- and under-represented in the MSP networks. Linkages between local and higher levels are weak, and influential organisations (e.g., high-level government actors) are often not part of the MSP or are not actively linked to by other organisations. Organisations with a central position in the knowledge network are more sought out for collaboration. The scaling of innovations is primarily between the same type of organisations across different administrative levels, but not between different types of organisations. The results illustrate the potential of Social Network Analysis and ERGMs to identify the strengths and limitations of MSPs in terms of achieving development impacts.

The biopolitics of needle exchange in the United States

PubMed Central

McLean, Katherine

2012-01-01

Needle exchange began in the United States as a fragmented and illegal practice initiated by actors at the grassroots level; since the late 1980s, needle exchange has achieved increasing yet variable levels of institutional support across the country, receiving official sanction and funding from state and municipal governments. In turn, the practice(s) and discourse(s) of needle exchange have shifted significantly in many locales, becoming the purview of professional administration that advocates needle exchange as a necessary public health measure. This article is interested in the ways in which needle exchange has become implicated in and appropriated by networks of power seeking to discipline and regulate injection drug use. Drawing theoretically on Michel Foucault’s writings concerning biopower and governmentality, it will examine the proliferation of discourses, knowledges, and rules surrounding needle exchange in the United States. At the same time, this article will avoid a characterization of needle exchange that envisions the unilateral control of drug users by governmental power, illuminating instead both its negative and productive effects for drug users. Namely, it will explore how needle exchange creates both subjects of interest and subjects of resistance among drug users – that is to say, the governmentalization of needle exchange and its ‘clients’. PMID:22389572

Energetics characteristics accounting for the explosive development of a twin extratropical cyclone over the Northwest Pacific Ocean

NASA Astrophysics Data System (ADS)

Fu, Shenming

2017-04-01

A twin extratropical cyclone that appeared over the Northwest Pacific Ocean during the winter of 2011 is reproduced reasonably well by the fifth-generation PSU-NCAR Mesoscale Model (MM5). One cyclone in this event has developed into an extreme explosive extratropical cyclone (EEC), with a maximum deepening rate up to 2.7 Bergeron, a minimum SLP of 933 hPa, and a maximum surface wind of 33 m s-1, which means its intensity is comparable with the intensity of a typhoon. The rotational and divergent wind kinetic energy (KE) budget equations are applied to this twin cyclone event so as to understand the rapid enhancement of the wind speed in this case. Preliminary results indicate that, overall, the rotational wind KE is much larger than the divergent wind KE, however, the latter can be of comparable intensity with the rotational wind KE around the regions where the wind speed strengthened most rapidly. Different quadrants of the twin cyclone show significant unevenness, overall, the southeastern quadrant of the EEC features the rapidest enhancement of wind speed, whereas the northwestern quadrant shows the slowest wind-speed acceleration. The vertical stretching of the EEC show consistent variation features with the rotational wind KE. The transport of KE by rotational wind, the conversion from divergent wind KE to rotational wind KE, and the work done by pressure gradient force all contributed to the enhancement of rotational wind KE. In contrast, the divergent wind KE is mainly produced by the baroclinic energy conversion.

Military Interoperable Digital Hospital Testbed (MIDHT) Phase III

DTIC Science & Technology

2014-10-01

silently changed, it is common knowledge  that some  Java  Development  Kit (JDK) implementations create slightly differently  formatted PEM and  DER...tracking software  JKS  Java  KeyStore  LDAP  Lightweight Directory Access Protocol  MHS  Military Health System  MIMC  Conemaugh Miners Medical... MySQL ~ Conemaugh Health System ’-J Common Access Layer (CAL) Interface I I t J J AIIScripts I I McKe-n J Sunque.st Horizon EHR Lab Patient

Radiative-emission analysis in charge-exchange collisions of O6 + with argon, water, and methane

NASA Astrophysics Data System (ADS)

Leung, Anthony C. K.; Kirchner, Tom

2017-04-01

Processes of electron capture followed by Auger and radiative decay were investigated in slow ion-atom and -molecule collisions. A quantum-mechanical analysis which utilizes the basis generator method within an independent electron model was carried out for collisions of O 6 + with Ar, H2O , and CH4 at impact energies of 1.17 and 2.33 keV/amu. At these impact energies, a closure approximation in the spectral representation of the Hamiltonian for molecules was found to be necessary to yield reliable results. Total single-, double-, and triple-electron-capture cross sections obtained show good agreement with previous measurements and calculations using the classical trajectory Monte Carlo method. The corresponding emission spectra from single capture for each collision system are in satisfactory agreement with previous calculations.

Ring current dynamics and plasma sheet sources. [magnetic storms

NASA Technical Reports Server (NTRS)

Lyons, L. R.

1984-01-01

The source of the energized plasma that forms in geomagnetic storm ring currents, and ring current decay are discussed. The dominant loss processes for ring current ions are identified as charge exchange and resonant interactions with ion-cyclotron waves. Ring current ions are not dominated by protons. At L4 and energies below a few tens of keV, O+ is the most abundant ion, He+ is second, and protons are third. The plasma sheet contributes directly or indirectly to the ring current particle population. An important source of plasma sheet ions is earthward streaming ions on the outer boundary of the plasma sheet. Ion interactions with the current across the geomagnetic tail can account for the formation of this boundary layer. Electron interactions with the current sheet are possibly an important source of plasma sheet electrons.

Neutral Beam Injection in the JET Trace Tritium Experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Surrey, E.; Ciric, D.; Cox, S. J.

Operation of the JET Neutral Beam Injectors with tritium is described. Supplying the tritium feed via the special electrically grounded gas feed compromised the performance of the up-graded high current triode Positive Ion Neutral Injectors (PINI) due to gas starvation of the source and the methods adopted to ameliorate this effect are described. A total of 362 PINI beam pulses were requested, circulating a total of 4.73g tritium, of which 9.3mg was injected into the torus. Safety considerations required a continuous, cumulative total to be maintained of the mass of tritium adsorbed onto the cryo-pumping panel; a daily limit ofmore » 0.5g was adopted for the Trace Tritium Experiment (TTE). A subsequent clean up phase using 115keV deuterium beams completed the isotopic exchange of components in the beamline.« less

A knowledge acquisition process to analyse operational problems in solid waste management facilities.

PubMed

Dokas, Ioannis M; Panagiotakopoulos, Demetrios C

2006-08-01

The available expertise on managing and operating solid waste management (SWM) facilities varies among countries and among types of facilities. Few experts are willing to record their experience, while few researchers systematically investigate the chains of events that could trigger operational failures in a facility; expertise acquisition and dissemination, in SWM, is neither popular nor easy, despite the great need for it. This paper presents a knowledge acquisition process aimed at capturing, codifying and expanding reliable expertise and propagating it to non-experts. The knowledge engineer (KE), the person performing the acquisition, must identify the events (or causes) that could trigger a failure, determine whether a specific event could trigger more than one failure, and establish how various events are related among themselves and how they are linked to specific operational problems. The proposed process, which utilizes logic diagrams (fault trees) widely used in system safety and reliability analyses, was used for the analysis of 24 common landfill operational problems. The acquired knowledge led to the development of a web-based expert system (Landfill Operation Management Advisor, http://loma.civil.duth.gr), which estimates the occurrence possibility of operational problems, provides advice and suggests solutions.

Energetic neutral atoms measured by the interstellar boundary explorer (IBEX): evidence for multiple heliosheath populations

DOE PAGES

Desai, M. I.; Allegrini, F. A.; Bzowski, M.; ...

2013-12-13

Energetic neutral atoms (ENAs) observed by the Interstellar Boundary Explorer (IBEX) provide powerful diagnostics about the origin of the progenitor ion populations and the physical mechanisms responsible for their production. In this paper, we extend the work of Desai et al. and Fuselier et al. and combine and compare ENA spectra from the first 3 yr of observations by the IBEX-Hi and -Lo ENA imagers along the lines-of-sight (LOSs) from the inner heliosphere through to the locations of Voyager 1 and 2 with results from an updated physics-based model of the three-dimensional heliosphere and its constituent ion populations. Our resultsmore » show that (1) IBEX ENA fluxes and spectra above ~0.7 keV measured along the LOSs of the Voyagers are consistent with several models in which the parent pickup ion (PUI) populations originate in the inner heliosheath, and (2) a significant fraction of lower energy ENAs between ~0.1-0.5 keV may originate from interstellar neutral gas charge-exchanging with a non-thermalized (hot) population of PUIs in the outer heliosheath beyond the heliopause. Here we discuss the implications of ENAs observed by IBEX originating from distinct parent populations as well as from two distinct locations in the heliospheric interface. In conclusion, these results indicate that ENA spectral measurements at various energies can be used to remotely probe distinct physical processes operating in vastly different regions of the distant heliosphere.« less

Energetic Neutral Atoms Measured by the Interstellar Boundary Explorer (IBEX): Evidence for Multiple Heliosheath Ion Populations

NASA Astrophysics Data System (ADS)

Desai, M. I.; Allegrini, F.; Bzowski, M.; Dayeh, M. A.; Funsten, H. O.; Fuselier, S.; Kubiak, M. A.; McComas, D. J.; Pogorelov, N. V.; Schwadron, N.; Sokol, J. M.; Zank, G. P.; Zirnstein, E. J.

2013-12-01

Energetic Neutral Atoms (ENAs) observed by the Interstellar Boundary Explorer (IBEX) provide powerful diagnostics about the origin of the progenitor ion populations and the physical mechanisms responsible for their production. In this paper, we extend the work of Desai et al. (2012) and Fuselier et al. (2012) and combine and compare ENA spectra from the first three years of observations by the IBEX-Hi and -Lo ENA imagers along the lines-of-sights (LOS) from the inner heliosphere through to the locations of Voyager 1 and 2 with results from an updated physics-based model of the 3D heliosphere and its constituent ion populations. Our results show that (1) IBEX ENA fluxes and spectra above ~0.7 keV measured along the LOS of the Voyagers are consistent with several models in which the parent pickup (PUI) populations originate in the inner heliosheath, and (2) a significant fraction of lower-energy ENAs between ~0.1-0.5 keV may originate from interstellar neutral gas charge-exchanging with a non-thermalized (hot) population of PUIs in the outer heliosheath beyond the heliopause. We discuss the implications of ENAs observed by IBEX originating from distinct parent populations as well as from two distinct locations in the heliospheric interface. These results indicate that ENA spectral measurements at various energies can be used to remotely probe distinct physical processes operating in vastly different regions of the distant heliosphere.

Energetic Neutral Atoms Measured by the Interstellar Boundary Explorer (IBEX): Evidence for Multiple Heliosheath Populations

NASA Astrophysics Data System (ADS)

Desai, M. I.; Allegrini, F. A.; Bzowski, M.; Dayeh, M. A.; Funsten, H.; Fuselier, S. A.; Heerikhuisen, J.; Kubiak, M. A.; McComas, D. J.; Pogorelov, N. V.; Schwadron, N. A.; Sokół, J. M.; Zank, G. P.; Zirnstein, E. J.

2014-01-01

Energetic neutral atoms (ENAs) observed by the Interstellar Boundary Explorer (IBEX) provide powerful diagnostics about the origin of the progenitor ion populations and the physical mechanisms responsible for their production. In this paper, we extend the work of Desai et al. and Fuselier et al. and combine and compare ENA spectra from the first 3 yr of observations by the IBEX-Hi and -Lo ENA imagers along the lines-of-sight (LOSs) from the inner heliosphere through to the locations of Voyager 1 and 2 with results from an updated physics-based model of the three-dimensional heliosphere and its constituent ion populations. Our results show that (1) IBEX ENA fluxes and spectra above ~0.7 keV measured along the LOSs of the Voyagers are consistent with several models in which the parent pickup ion (PUI) populations originate in the inner heliosheath, and (2) a significant fraction of lower energy ENAs between ~0.1-0.5 keV may originate from interstellar neutral gas charge-exchanging with a non-thermalized (hot) population of PUIs in the outer heliosheath beyond the heliopause. We discuss the implications of ENAs observed by IBEX originating from distinct parent populations as well as from two distinct locations in the heliospheric interface. These results indicate that ENA spectral measurements at various energies can be used to remotely probe distinct physical processes operating in vastly different regions of the distant heliosphere.

X-ray spectroscopy with silicon pin and avalanche photo diodes

NASA Technical Reports Server (NTRS)

Desai, U. D.

1992-01-01

Results of an evaluation of silicon P-Intrinsic-N (PIN) photodiodes and Avalanche Photodiodes (APD) for the direct detection of soft x rays from 1 to 20 keV and for the detection of scintillation light output from CsI(TI) for higher x ray energies (30 to 1000 keV) are presented. About one keV resolution was achieved at room temperature for both the PIN and APD detectors for soft x rays (1 to 20 keV). Commercially available, low power (18 mV), low noise, hybrid preamplifiers, were used. These photodiodes were also coupled to CsI(TI) scintillator and obtained about 6 resolution at 662 keV. The photodiode frequency response matches well with the emission spectrum of the CsI(TI) scintillator providing good spectral resolution and a higher signal than NaI(TI) when viewed by conventional photomultipliers. A PIN-CsI(TI) combination provides a low energy threshold of around 60 keV while for the APD-CsI(TI) it is 15 keV.

Plant mineral nutrition, gas exchange and photosynthesis in space: A review

NASA Astrophysics Data System (ADS)

Wolff, S. A.; Coelho, L. H.; Zabrodina, M.; Brinckmann, E.; Kittang, A.-I.

2013-02-01

Successful growth and development of higher plants in space rely on adequate availability and uptake of water and nutrients, and efficient energy distribution through photosynthesis and gas exchange. In the present review, literature has been reviewed to assemble the relevant knowledge within space plant research for future planetary missions. Focus has been on fractional gravity, space radiation, magnetic fields and ultimately a combined effect of these factors on gas exchange, photosynthesis and transport of water and solutes. Reduced gravity prevents buoyancy driven thermal convection in the physical environment around the plant and alters transport and exchange of gases and liquids between the plant and its surroundings. In space experiments, indications of root zone hypoxia have frequently been reported, but studies on the influences of the space environment on plant nutrition and water transport are limited or inconclusive. Some studies indicate that uptake of potassium is elevated when plants are grown under microgravity conditions. Based on the current knowledge, gas exchange, metabolism and photosynthesis seem to work properly in space when plants are provided with a well stirred atmosphere and grown at moderate light levels. Effects of space radiation on plant metabolism, however, have not been studied so far in orbit. Ground experiments indicated that shielding from the Earth's magnetic field alters plant gas exchange and metabolism, though more studies are required to understand the effects of magnetic fields on plant growth. It has been shown that plants can grow and reproduce in the space environment and adapt to space conditions. However, the influences of the space environment may result in a long term effect over multiple generations or have an impact on the plants' role as food and part of a regenerative life support system. Suggestions for future plant biology research in space are discussed.

Engaging pediatric intensive care unit (PICU) clinical staff to lead practice improvement: the PICU participatory action research project (PICU-PAR).

PubMed

Collet, Jean-Paul; Skippen, Peter W; Mosavianpour, Mir Kaber; Pitfield, Alexander; Chakraborty, Bubli; Hunte, Garth; Lindstrom, Ronald; Kissoon, Niranjan; McKellin, William H

2014-01-08

Despite considerable efforts, engaging staff to lead quality improvement activities in practice settings is a persistent challenge. At British Columbia Children's Hospital (BCCH), the pediatric intensive care unit (PICU) undertook a new phase of quality improvement actions based on the Community of Practice (CoP) model with Participatory Action Research (PAR). This approach aims to mobilize the PICU 'community' as a whole with a focus on practice; namely, to create a 'community of practice' to support reflection, learning, and innovation in everyday work. An iterative two-stage PAR process using mixed methods has been developed among the PICU CoP to describe the environment (stage 1) and implement specific interventions (stage 2). Stage 1 is ethnographic description of the unit's care practice. Surveys, interviews, focus groups, and direct observations describe the clinical staff's experiences and perspectives around bedside care and quality endeavors in the PICU. Contrasts and comparisons across participants, time and activities help understanding the PICU culture and experience. Stage 2 is a succession of PAR spirals, using results from phase 1 to set up specific interventions aimed at building the staff's capability to conduct QI projects while acquiring appropriate technical skills and leadership capacity (primary outcome). Team communication, information, and interaction will be enhanced through a knowledge exchange (KE) and a wireless network of iPADs. Lack of leadership at the staff level in order to improve daily practice is a recognized challenge that faces many hospitals. We believe that the PAR approach within a highly motivated CoP is a sound method to create the social dynamic and cultural context within which clinical teams can grow, reflect, innovate and feel proud to better serve patients.

Engaging Pediatric Intensive Care Unit (PICU) clinical staff to lead practice improvement: the PICU Participatory Action Research Project (PICU-PAR)

PubMed Central

2014-01-01

Background Despite considerable efforts, engaging staff to lead quality improvement activities in practice settings is a persistent challenge. At British Columbia Children’s Hospital (BCCH), the pediatric intensive care unit (PICU) undertook a new phase of quality improvement actions based on the Community of Practice (CoP) model with Participatory Action Research (PAR). This approach aims to mobilize the PICU ‘community’ as a whole with a focus on practice; namely, to create a ‘community of practice’ to support reflection, learning, and innovation in everyday work. Methodology An iterative two-stage PAR process using mixed methods has been developed among the PICU CoP to describe the environment (stage 1) and implement specific interventions (stage 2). Stage 1 is ethnographic description of the unit’s care practice. Surveys, interviews, focus groups, and direct observations describe the clinical staff’s experiences and perspectives around bedside care and quality endeavors in the PICU. Contrasts and comparisons across participants, time and activities help understanding the PICU culture and experience. Stage 2 is a succession of PAR spirals, using results from phase 1 to set up specific interventions aimed at building the staff’s capability to conduct QI projects while acquiring appropriate technical skills and leadership capacity (primary outcome). Team communication, information, and interaction will be enhanced through a knowledge exchange (KE) and a wireless network of iPADs. Relevance Lack of leadership at the staff level in order to improve daily practice is a recognized challenge that faces many hospitals. We believe that the PAR approach within a highly motivated CoP is a sound method to create the social dynamic and cultural context within which clinical teams can grow, reflect, innovate and feel proud to better serve patients. PMID:24401288

Plasma surrounding the global heliosphere at large distances controlled by the solar cycle

NASA Astrophysics Data System (ADS)

Dialynas, Konstantinos; Krimigis, Stamatios; Mitchell, Donald; Decker, Robert; Roelof, Edmond

2016-04-01

The past decade can be characterized by a series of key, groundbreaking remote energetic neutral atom (ENA) images (INCA, IBEX) and in-situ ion (Voyager 1 & 2) observations concerning the characteristics and interactions of the heliosphere with the Local Interstellar Medium (LISM). Voyagers 1 and 2 (V1, V2) discovered the reservoir of ions and electrons that constitute the heliosheath (HS) after crossing the termination shock (TS) 35deg north and 32deg south of the ecliptic plane at 94 and 84 astronomical units (1 AU= 1.5 x108 km), respectively. The in situ measurements by each Voyager were placed in a global context by remote sensing images using ENA obtained with the Ion and Neutral Camera (INCA) onboard Cassini orbiting Saturn. The ENA images contain a 5.2-55 keV hydrogen (H) ENA region (Belt) that loops through the celestial sphere and contributes to balancing the pressure of the interstellar magnetic field (ISMF). The success of any future mission with dedicated ENA detectors (e.g. the IMAP mission), highly depends on the antecedent understanding of the details of the plasma processes in the Heliosphere as revealed by remote sensing of the plasma environment characteristics. Therefore, we address here one of the remaining and most important questions: "Where do the 5-55 keV ENAs that INCA measures come from?". We analyzed INCA all-sky maps from 2003 to 2015 and compare the solar cycle (SC) variation of the ENAs in both the nose (upstream) and anti-nose (downstream) directions with the intensities of > 30 keV ions (source of ENA through charge exchange-CE with H) measured in-situ by V1 and V2, in overlapping energy bands ~30-55 keV. ENA intensities decrease during the declining phase of SC23 by ~x3 from 2003 to 2011 but recover through 2014 (SC24); similarly, V1 and V2 ion intensities also decrease and then recover through 2014. The similarity of time profiles of remotely sensed ENA and locally measured ions are consistent with (a) ENA originating in the HS, and (b) the global HS responding promptly (within ~1-1.5 years) to outward-propagating solar wind changes throughout the SC. Further, recovery of the Belt during SC24 precedes asymmetrically from south to north in the general direction of the nose. This may be related to the non-symmetric evolution of solar coronal holes during SC recovery.

Application of the adverse outcome pathway (AOP) concept to structure the available in vivo and in vitro mechanistic data for allergic sensitization to food proteins.

PubMed

van Bilsen, Jolanda H M; Sienkiewicz-Szłapka, Edyta; Lozano-Ojalvo, Daniel; Willemsen, Linette E M; Antunes, Celia M; Molina, Elena; Smit, Joost J; Wróblewska, Barbara; Wichers, Harry J; Knol, Edward F; Ladics, Gregory S; Pieters, Raymond H H; Denery-Papini, Sandra; Vissers, Yvonne M; Bavaro, Simona L; Larré, Colette; Verhoeckx, Kitty C M; Roggen, Erwin L

2017-01-01

The introduction of whole new foods in a population may lead to sensitization and food allergy. This constitutes a potential public health problem and a challenge to risk assessors and managers as the existing understanding of the pathophysiological processes and the currently available biological tools for prediction of the risk for food allergy development and the severity of the reaction are not sufficient. There is a substantial body of in vivo and in vitro data describing molecular and cellular events potentially involved in food sensitization. However, these events have not been organized in a sequence of related events that is plausible to result in sensitization, and useful to challenge current hypotheses. The aim of this manuscript was to collect and structure the current mechanistic understanding of sensitization induction to food proteins by applying the concept of adverse outcome pathway (AOP). The proposed AOP for food sensitization is based on information on molecular and cellular mechanisms and pathways evidenced to be involved in sensitization by food and food proteins and uses the AOPs for chemical skin sensitization and respiratory sensitization induction as templates. Available mechanistic data on protein respiratory sensitization were included to fill out gaps in the understanding of how proteins may affect cells, cell-cell interactions and tissue homeostasis. Analysis revealed several key events (KE) and biomarkers that may have potential use in testing and assessment of proteins for their sensitizing potential. The application of the AOP concept to structure mechanistic in vivo and in vitro knowledge has made it possible to identify a number of methods, each addressing a specific KE, that provide information about the food allergenic potential of new proteins. When applied in the context of an integrated strategy these methods may reduce, if not replace, current animal testing approaches. The proposed AOP will be shared at the www.aopwiki.org platform to expand the mechanistic data, improve the confidence in each of the proposed KE and key event relations (KERs), and allow for the identification of new, or refinement of established KE and KERs.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lippincott, W. H.; McKinsey, D. N.; Nikkel, J. A.

Using a single-phase liquid argon detector with a signal yield of 4.85 photoelectrons per keV of electronic-equivalent recoil energy (keVee), we measure the scintillation time dependence of both electronic and nuclear recoils in liquid argon down to 5 keVee. We develop two methods of pulse shape discrimination to distinguish between electronic and nuclear recoils. Using one of these methods, we measure a background- and statistics-limited level of electronic recoil contamination to be 7.6x10{sup -7} between 52 and 110 keV of nuclear recoil energy (keVr) for a nuclear recoil acceptance of 50% with no nuclear recoil-like events above 62 keVr. Finally,more » we develop a maximum likelihood method of pulse shape discrimination based on the measured scintillation time dependence.« less

Improving care and wellness in bipolar disorder: origins, evolution and future directions of a collaborative knowledge exchange network

PubMed Central

2012-01-01

The Collaborative RESearch team to study psychosocial factors in bipolar disorder (CREST.BD) is a multidisciplinary, cross-sectoral network dedicated to both fundamental research and knowledge exchange on bipolar disorder (BD). The core mission of the network is to advance the science and understanding of psychological and social issues associated with BD, improve the care and wellness of people living with BD, and strengthen services and supports for these individuals. CREST.BD bridges traditional and newer research approaches, particularly embracing community-based participatory research (CBPR) methods. Membership of CREST is broad, including academic researchers, people with BD, their family members and supports, and a variety of health care providers. Here, we describe the origins, evolution, approach to planning and evaluation and future vision for our network within the landscape of CBPR and integrated knowledge translation (KT), and explore the keys and challenges to success we have encountered working within this framework. PMID:22963889

High-precision measurement of the light response of BC-418 plastic scintillator to protons with energies from 100 keV to 10 MeV

NASA Astrophysics Data System (ADS)

Henzl, Vladimir; Daub, Brian; French, Jennifer; Matthews, June; Kovash, Michael; Wender, Stephen; Famiano, Michael; Koehler, Katrina; Yuly, Mark

2010-11-01

The determination of the light response of many organic scintillators to various types of radiation has been a subject of numerous experimental as well as theoretical studies in the past. But while the data on light response to particles with energies above 1 MeV are precise and abundant, the information on light response to very low energy particles (i.e. below 1 MeV) is scarce or completely missing. In this study we measured the light response of a BC-418 scintillator to protons with energies from 100 keV to 10 MeV. The experiment was performed at Weapons Neutron Research Facility at LANSCE, Los Alamos. The neutron beam from a spallation source is used to irradiate the active target made from BC-418 plastic scintillator. The recoiled protons detected in the active target are measured in coincidence with elastically scattered incident neutrons detected by and adjacent liquid scintillator. Time of flight of the incident neutron and the knowledge of scattering geometry allow for a kinematically complete and high-precision measurement of the light response as a function of the proton energy.

Inferred UV Fluence Focal-Spot Profiles from Soft X-Ray Pinhole Camera Measurements on OMEGA

NASA Astrophysics Data System (ADS)

Theobald, W.; Sorce, C.; Epstein, R.; Keck, R. L.; Kellogg, C.; Kessler, T. J.; Kwiatkowski, J.; Marshall, F. J.; Seka, W.; Shvydky, A.; Stoeckl, C.

2017-10-01

The drive uniformity of OMEGA cryogenic implosions is affected by UV beamfluence variations on target, which require careful monitoring at full laser power. This is routinely performed with multiple pinhole cameras equipped with charge-injection devices (CID's) that record the x-ray emission in the 3- to 7-keV photon energy range from an Au-coated target. The technique relies on the knowledge of the relation between x-ray fluence Fx and UV fluence FUV ,Fx FUVγ , with a measured γ = 3.42 for the CID-based diagnostic and 1-ns laser pulse. It is demonstrated here that using a back-thinned charge-coupled-device camera with softer filtration for x-rays with photon energies <2 keV and well calibrated pinhole provides a lower γ 2 and a larger dynamic range in the measured UV fluence. Inferred UV fluence profiles were measured for 100-ps and 1-ns laser pulses and were compared to directly measured profiles from a UV equivalent-target-plane diagnostic. Good agreement between both techniques is reported for selected beams. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

The 19F(α, p)22Ne Reaction at Energies of Astrophysical Relevance by Means of the Trojan Horse Method and Its Implications in AGB Stars

NASA Astrophysics Data System (ADS)

D’Agata, G.; Pizzone, R. G.; La Cognata, M.; Indelicato, I.; Spitaleri, C.; Palmerini, S.; Trippella, O.; Vescovi, D.; Blagus, S.; Cherubini, S.; Figuera, P.; Grassi, L.; Guardo, G. L.; Gulino, M.; Hayakawa, S.; Kshetri, R.; Lamia, L.; Lattuada, M.; Mijatovic`, T.; Milin, M.; Miljanic`, Đ.; Prepolec, L.; Rapisarda, G. G.; Romano, S.; Sergi, M. L.; Skukan, N.; Soic`, N.; Tokic`, V.; Tumino, A.; Uroic`, M.

2018-06-01

The main source of 19F in the universe has not yet been clearly identified and this issue represents one of the unanswered questions of stellar modeling. This lack of knowledge can be due to the 19F(α, p)22Ne reaction cross-section that has proven to be difficult at low energies: direct measurements stop only at about ∼660 keV, leaving roughly half of the astrophysical relevant energy region (from 200 keV to 1.1 MeV) explored only by R-matrix calculations. In this work, we applied the Trojan Horse Method to the quasi-free three-body 6Li(19F, p22Ne)d reaction performed at E beam = 6 MeV in order to indirectly study the 19F(α, p)22Ne reaction in the sub-Coulomb energy region. In this way, we obtained the cross-section and the reaction rate in the temperature region of interest for astrophysics and free from electron screening effects. A brief analysis of the impact of the new measured reaction rate in AGB star nucleosynthesis is also presented.

L i ( i = 1-3) subshell X-ray production cross sections and fluorescence yields for some elements with 56 ⩽ Z ⩽ 68 at 22.6 keV

NASA Astrophysics Data System (ADS)

Chauhan, Yogeshwar; Tiwari, M. K.; Puri, Sanjiv

2008-01-01

The L k ( k = l, α, β 1,4, β 3,6, β 2,15,9,10,7, γ 1,5 and γ 2,3,4) X-ray production (XRP) cross sections have been measured for six elements with 56 ⩽ Z ⩽ 68 at 22.6 keV incident photon energy using the EDXRF spectrometer. The incident photon intensity, detector efficiency and geometrical factors have been determined from the K X-ray yields emitted from elemental targets with 22 ⩽ Z ⩽ 42 in the same geometrical setup and from knowledge of the K XRP cross sections. The L 1 and L 2 subshell fluorescence yields have been deduced from the present measured L k XRP cross sections using the relativistic Hartree-Fock-Slater (HFS) model based photoionization cross sections. The present deduced ω1 (exp) values have been found to be, on an average, higher by 15% and 20% than those based on the Dirac-Hartree-Slater (DHS) model and the semi-empirical values compiled by Krause, respectively, for elements with 60 ⩽ Z ⩽ 68.

Enhanced Control of Listeria monocytogenes by Enterococcus faecium KE82, a Multiple Enterocin-Producing Strain, in Different Milk Environments.

PubMed

Vandera, Elpiniki; Lianou, Alexandra; Kakouri, Athanasia; Feng, Jinbo; Koukkou, Anna-Irini; Samelis, John

2017-01-01

Enterococcus faecium KE82, isolated from traditional Greek Graviera cheese, was identified in pure broth cultures in vitro as a multiple enterocin-producing bacterial strain possessing the structural entA, entB, and entP enterocin genes. E. faecium KE82 was further assessed for in situ antilisterial activity in raw milk (RM) and commercially thermized milk (TM; 63°C for 30 s) in the presence of the indigenous microbiota and in sterile raw milk (SRM; 121°C for 5 min) with or without the addition of two commercial starter culture (CSC) strains Streptococcus thermophilus and Lactococcus lactis . Growth of Listeria monocytogenes was completely inhibited in RM incubated at 37°C for 6 h, whereas the pathogen was significantly inactivated in RM+KE82 samples during further incubation at 18°C for 66 h. In contrast, L. monocytogenes levels increased by approximately 2 log CFU/ml in TM, but in TM+KE82 samples, pathogen growth was retarded during the first 6 h at 37°C followed by growth cessation and partial inactivation at 18°C. After 48 to 72 h, growth of L. monocytogenes in SRM+CSC samples decreased by 4 to 5 log CFU/ml compared with the SRM control, whereas additional 10-fold decreases in the pathogen were observed in SRM+CSC+KE82 samples. Reverse transcription PCR analysis of SRM+KE82 and SRM+CSC+KE82 samples confirmed that the entA and entB genes were transcribed, but entP gene transcription was not detected. All RM and SRM samples inoculated with E. faecium KE82 displayed strong in situ inhibitory activity against L. monocytogenes in well diffusion bioassays, whereas activity was weaker to undetectable in comparable or additional TM+KE82 samples; no milk sample without E. faecium KE82 had activity against L. monocytogenes . The findings of this study indicate that E. faecium KE82 is an antilisterial agent that could be used in traditional dairy foods because it concomitantly produces enterocins A and B in situ in milk.

The mediating role of job satisfaction between leader-member exchange and turnover intentions.

PubMed

Han, Guohong Helen; Jekel, Marc

2011-01-01

The aim of the present study was to investigate whether job satisfaction mediates between leader-member exchange and nurse turnover intentions. Limited knowledge is available on the mediating role of job satisfaction between leader-member exchange and turnover intentions in the nursing field. This is a cross-sectional survey study. Data were collected in a US hospital. Higher leader-member exchange was associated with lower turnover intentions (β=-0.41, P<0.001). Leader-member exchange was positively related to one's job satisfaction (β=0.50, P<0.001). Job satisfaction was negatively related to turnover intentions (β=-0.64, P<0.001). When leader-member exchange and job satisfaction were both controlled for, the link between leader-member exchange and turnover intentions was no longer significant (β=-0.12, P>0.05). Job satisfaction mediates the link between leader-member exchange and turnover intentions. The present study reinforces the significant role of managers. Nurse managers can try to cultivate a good relationship with the nurses. This can enhance nurses' job satisfaction and in turn lower their turnover intentions. © 2010 The Authors. Journal compilation © 2010 Blackwell Publishing Ltd.

Track Structure and the Biological Effectiveness of Accelerated Particles for the Induction of Chromosome Damage

NASA Technical Reports Server (NTRS)

George, K.; Hada, M.; Chappell, L.; Cucinotta, F. A.

2011-01-01

Track structure models predict that at a fixed value of LET, particles with lower charge number, Z will have a higher biological effectiveness compared to particles with a higher Z. In this report we investigated how track structure effects induction of chromosomal aberration in human cells. Human lymphocytes were irradiated in vitro with various energies of accelerated iron, silicon, neon, or titanium ions and chromosome damage was assessed in using three color FISH chromosome painting in chemically induced PCC samples collected a first cell division post irradiation. The LET values for these ions ranged from 30 to195 keV/micron. Of the particles studied, Neon ions have the highest biological effectiveness for induction of total chromosome damage, which is consistent with track structure model predictions. For complex-type exchanges 64 MeV/ u Neon and 450 MeV/u Iron were equally effective and induced the most complex damage. In addition we present data on chromosomes exchanges induced by six different energies of protons (5 MeV/u to 2.5 GeV/u). The linear dose response term was similar for all energies of protons suggesting that the effect of the higher LET at low proton energies is balanced by the production of nuclear secondaries from the high energy protons.

The Si/CdTe semiconductor Compton camera of the ASTRO-H Soft Gamma-ray Detector (SGD)

NASA Astrophysics Data System (ADS)

Watanabe, Shin; Tajima, Hiroyasu; Fukazawa, Yasushi; Ichinohe, Yuto; Takeda, Shin`ichiro; Enoto, Teruaki; Fukuyama, Taro; Furui, Shunya; Genba, Kei; Hagino, Kouichi; Harayama, Atsushi; Kuroda, Yoshikatsu; Matsuura, Daisuke; Nakamura, Ryo; Nakazawa, Kazuhiro; Noda, Hirofumi; Odaka, Hirokazu; Ohta, Masayuki; Onishi, Mitsunobu; Saito, Shinya; Sato, Goro; Sato, Tamotsu; Takahashi, Tadayuki; Tanaka, Takaaki; Togo, Atsushi; Tomizuka, Shinji

2014-11-01

The Soft Gamma-ray Detector (SGD) is one of the instrument payloads onboard ASTRO-H, and will cover a wide energy band (60-600 keV) at a background level 10 times better than instruments currently in orbit. The SGD achieves low background by combining a Compton camera scheme with a narrow field-of-view active shield. The Compton camera in the SGD is realized as a hybrid semiconductor detector system which consists of silicon and cadmium telluride (CdTe) sensors. The design of the SGD Compton camera has been finalized and the final prototype, which has the same configuration as the flight model, has been fabricated for performance evaluation. The Compton camera has overall dimensions of 12 cm×12 cm×12 cm, consisting of 32 layers of Si pixel sensors and 8 layers of CdTe pixel sensors surrounded by 2 layers of CdTe pixel sensors. The detection efficiency of the Compton camera reaches about 15% and 3% for 100 keV and 511 keV gamma rays, respectively. The pixel pitch of the Si and CdTe sensors is 3.2 mm, and the signals from all 13,312 pixels are processed by 208 ASICs developed for the SGD. Good energy resolution is afforded by semiconductor sensors and low noise ASICs, and the obtained energy resolutions with the prototype Si and CdTe pixel sensors are 1.0-2.0 keV (FWHM) at 60 keV and 1.6-2.5 keV (FWHM) at 122 keV, respectively. This results in good background rejection capability due to better constraints on Compton kinematics. Compton camera energy resolutions achieved with the final prototype are 6.3 keV (FWHM) at 356 keV and 10.5 keV (FWHM) at 662 keV, which satisfy the instrument requirements for the SGD Compton camera (better than 2%). Moreover, a low intrinsic background has been confirmed by the background measurement with the final prototype.

Optimal Monochromatic Energy Levels in Spectral CT Pulmonary Angiography for the Evaluation of Pulmonary Embolism

PubMed Central

Wu, Huawei; Zhang, Qing; Hua, Jia; Hua, Xiaolan; Xu, Jianrong

2013-01-01

Background The aim of this study was to determine the optimal monochromatic spectral CT pulmonary angiography (sCTPA) levels to obtain the highest image quality and diagnostic confidence for pulmonary embolism detection. Methods The Institutional Review Board of the Shanghai Jiao Tong University School of Medicine approved this study, and written informed consent was obtained from all participating patients. Seventy-two patients with pulmonary embolism were scanned with spectral CT mode in the arterial phase. One hundred and one sets of virtual monochromatic spectral (VMS) images were generated ranging from 40 keV to 140 keV. Image noise, clot diameter and clot to artery contrast-to-noise ratio (CNR) from seven sets of VMS images at selected monochromatic levels in sCTPA were measured and compared. Subjective image quality and diagnostic confidence for these images were also assessed and compared. Data were analyzed by paired t test and Wilcoxon rank sum test. Results The lowest noise and the highest image quality score for the VMS images were obtained at 65 keV. The VMS images at 65 keV also had the second highest CNR value behind that of 50 keV VMS images. There was no difference in the mean noise and CNR between the 65 keV and 70 keV VMS images. The apparent clot diameter correlated with the keV levels. Conclusions The optimal energy level for detecting pulmonary embolism using dual-energy spectral CT pulmonary angiography was 65–70 keV. Virtual monochromatic spectral images at approximately 65–70 keV yielded the lowest image noise, high CNR and highest diagnostic confidence for the detection of pulmonary embolism. PMID:23667583

Using knowledge translation as a framework for the design of a research protocol.

PubMed

Fredericks, Suzanne; Martorella, Géraldine; Catallo, Cristina

2015-05-01

Knowledge translation has been defined as the synthesis, dissemination, exchange and ethically sound application of knowledge to improve health, resulting in a stronger health-care system. Using KT activities to aid in the adoption of evidence into practice can address current health-care challenges such as increasing organizational practice standards, alleviating the risk for adverse events and meeting practitioner needs for evidence at the bedside. Two general forms of KT have been identified. These being integrated KT and end-of-grant KT. Integrated KT involves the knowledge users in the research team and in the majority of stages of the research process. End-of-grant KT relates to the translation of findings through a well-developed dissemination plan. This paper describes the process of using an integrated knowledge translation approach to design a research protocol that will examine the effectiveness of a web-based patient educational intervention. It begins with a description of integrated knowledge translation, followed by the presentation of a specific case example in which integrated knowledge translation is used to develop a nursing intervention. The major elements of integrated knowledge translation pertain to need for a knowledge user who represents the broad target user group, and who is knowledgeable in the area under investigation and who as authority to enact changes to practice. Use of knowledge users as equal partners within the research team; exploring all feasible opportunities for knowledge exchange; and working with knowledge users to identify all outcomes related to knowledge translation are the other major elements of integrated knowledge translation that are addressed throughout this paper. Furthermore, the relevance of psychosocial or educational interventions to knowledge translation is also discussed as a source of knowledge. In summary, integrated knowledge translation is an important tool for the development of new interventions, as it helps to apply science to practice accurately. It supports the elaboration of the design while enhancing the relevance of the intervention through the validation of feasibility and acceptability with clinicians and patients. © 2015 Wiley Publishing Asia Pty Ltd.

Quality management benchmarking: FDA compliance in pharmaceutical industry.

PubMed

Jochem, Roland; Landgraf, Katja

2010-01-01

By analyzing and comparing industry and business best practice, processes can be optimized and become more successful mainly because efficiency and competitiveness increase. This paper aims to focus on some examples. Case studies are used to show knowledge exchange in the pharmaceutical industry. Best practice solutions were identified in two companies using a benchmarking method and five-stage model. Despite large administrations, there is much potential regarding business process organization. This project makes it possible for participants to fully understand their business processes. The benchmarking method gives an opportunity to critically analyze value chains (a string of companies or players working together to satisfy market demands for a special product). Knowledge exchange is interesting for companies that like to be global players. Benchmarking supports information exchange and improves competitive ability between different enterprises. Findings suggest that the five-stage model improves efficiency and effectiveness. Furthermore, the model increases the chances for reaching targets. The method gives security to partners that did not have benchmarking experience. The study identifies new quality management procedures. Process management and especially benchmarking is shown to support pharmaceutical industry improvements.

Collaborative Information Agents on the World Wide Web

NASA Technical Reports Server (NTRS)

Chen, James R.; Mathe, Nathalie; Wolfe, Shawn; Koga, Dennis J. (Technical Monitor)

1998-01-01

In this paper, we present DIAMS, a system of distributed, collaborative information agents which help users access, collect, organize, and exchange information on the World Wide Web. Personal agents provide their owners dynamic displays of well organized information collections, as well as friendly information management utilities. Personal agents exchange information with one another. They also work with other types of information agents such as matchmakers and knowledge experts to facilitate collaboration and communication.

Information Technologies as a Tool for Agricultural Extension and Farmer-to-Farmer Exchange: Mobile-Phone Video Use in Mali and Burkina Faso

ERIC Educational Resources Information Center

Sousa, Fernando; Nicolay, Gian; Home, Robert

2016-01-01

Mobile phones are widespread in the rural areas of Mali and Burkina Faso, but their potential as a tool for knowledge transfer by extension services in the region remains largely unexplored. The aim of this contribution is to evaluate the potential of video on mobile phones as a tool for farmer-to-farmer exchange and agricultural extension in…

A 7.2 keV spherical x-ray crystal backlighter for two-frame, two-color backlighting at Sandia's Z Pulsed Power Facility

NASA Astrophysics Data System (ADS)

Schollmeier, M. S.; Knapp, P. F.; Ampleford, D. J.; Harding, E. C.; Jennings, C. A.; Lamppa, D. C.; Loisel, G. P.; Martin, M. R.; Robertson, G. K.; Shores, J. E.; Smith, I. C.; Speas, C. S.; Weis, M. R.; Porter, J. L.; McBride, R. D.

2017-10-01

Many experiments on Sandia National Laboratories' Z Pulsed Power Facility—a 30 MA, 100 ns rise-time, pulsed-power driver—use a monochromatic quartz crystal backlighter system at 1.865 keV (Si He α ) or 6.151 keV (Mn He α ) x-ray energy to radiograph an imploding liner (cylindrical tube) or wire array z-pinch. The x-ray source is generated by the Z-Beamlet laser, which provides two 527-nm, 1 kJ, 1-ns laser pulses. Radiographs of imploding, thick-walled beryllium liners at convergence ratios CR above 15 [ C R = r i ( 0 ) / r i ( t ) ] using the 6.151-keV backlighter system were too opaque to identify the inner radius r i of the liner with high confidence, demonstrating the need for a higher-energy x-ray radiography system. Here, we present a 7.242 keV backlighter system using a Ge(335) spherical crystal with the Co He α resonance line. This system operates at a similar Bragg angle as the existing 1.865 keV and 6.151 keV backlighters, enhancing our capabilities for two-color, two-frame radiography without modifying the system integration at Z. The first data taken at Z include 6.2-keV and 7.2-keV two-color radiographs as well as radiographs of low-convergence (CR about 4-5), high-areal-density liner implosions.

Precise Determination of the Intensity of 226Ra Alpha Decay to the 186 keV Excited State

DOE Office of Scientific and Technical Information (OSTI.GOV)

S.P. LaMont; R.J. Gehrke; S.E. Glover

There is a significant discrepancy in the reported values for the emission probability of the 186 keV gamma-ray resulting from the alpha decay of 226 Ra to 186 keV excited state of 222 Rn. Published values fall in the range of 3.28 to 3.59 gamma-rays per 100 alpha-decays. An interesting observation is that the lower value, 3.28, is based on measuring the 186 keV gamma-ray intensity relative to the 226 Ra alpha-branch to the 186 keV level. The higher values, which are close to 3.59, are based on measuring the gamma-ray intensity from mass standards of 226 Ra that aremore » traceable to the mass standards prepared by HÓNIGSCHMID in the early 1930''s. This discrepancy was resolved in this work by carefully measuring the 226 Ra alpha-branch intensities, then applying the theoretical E2 multipolarity internal conversion coefficient of 0.692±0.007 to calculate the 186 keV gamma-ray emission probability. The measured value for the alpha branch to the 186 keV excited state was (6.16±0.03)%, which gives a 186 keV gamma-ray emission probability of (3.64±0.04)%. This value is in excellent agreement with the most recently reported 186 keV gamma-ray emission probabilities determined using 226 Ra mass standards.« less

A 7.2 keV spherical x-ray crystal backlighter for two-frame, two-color backlighting at Sandia’s Z Pulsed Power Facility

DOE PAGES

Schollmeier, M. S.; Knapp, P. F.; Ampleford, D. J.; ...

2017-10-10

Many experiments on Sandia National Laboratories’ Z Pulsed Power Facility—a 30 MA, 100 ns rise-time, pulsed-power driver—use a monochromatic quartz crystal backlighter system at 1.865 keV (Si He α) or 6.151 keV (Mn He α) x-ray energy to radiograph an imploding liner (cylindrical tube) or wire array z-pinch. The x-ray source is generated by the Z-Beamlet laser, which provides two 527-nm, 1 kJ, 1-ns laser pulses. Radiographs of imploding, thick-walled beryllium liners at convergence ratios C R above 15 [C R=r i(0)/r i(t)] using the 6.151-keV backlighter system were too opaque to identify the inner radius ri of the linermore » with high confidence, demonstrating the need for a higher-energy x-ray radiography system. Here, we present a 7.242 keV backlighter system using a Ge(335) spherical crystal with the Co He α resonance line. This system operates at a similar Bragg angle as the existing 1.865 keV and 6.151 keV backlighters, enhancing our capabilities for two-color, two-frame radiography without modifying the system integration at Z. The first data taken at Z include 6.2-keV and 7.2-keV two-color radiographs as well as radiographs of low-convergence (C R about 4-5), high-areal-density liner implosions.« less

A 7.2 keV spherical x-ray crystal backlighter for two-frame, two-color backlighting at Sandia’s Z Pulsed Power Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schollmeier, M. S.; Knapp, P. F.; Ampleford, D. J.

Many experiments on Sandia National Laboratories’ Z Pulsed Power Facility—a 30 MA, 100 ns rise-time, pulsed-power driver—use a monochromatic quartz crystal backlighter system at 1.865 keV (Si He α) or 6.151 keV (Mn He α) x-ray energy to radiograph an imploding liner (cylindrical tube) or wire array z-pinch. The x-ray source is generated by the Z-Beamlet laser, which provides two 527-nm, 1 kJ, 1-ns laser pulses. Radiographs of imploding, thick-walled beryllium liners at convergence ratios C R above 15 [C R=r i(0)/r i(t)] using the 6.151-keV backlighter system were too opaque to identify the inner radius ri of the linermore » with high confidence, demonstrating the need for a higher-energy x-ray radiography system. Here, we present a 7.242 keV backlighter system using a Ge(335) spherical crystal with the Co He α resonance line. This system operates at a similar Bragg angle as the existing 1.865 keV and 6.151 keV backlighters, enhancing our capabilities for two-color, two-frame radiography without modifying the system integration at Z. The first data taken at Z include 6.2-keV and 7.2-keV two-color radiographs as well as radiographs of low-convergence (C R about 4-5), high-areal-density liner implosions.« less

"A Gentleman's Handshake": The Role of Social Capital and Trust in Transforming Information into Usable Knowledge

ERIC Educational Resources Information Center

Fisher, Rhiannon

2013-01-01

This paper explores the role of various social ties in building trust and providing opportunities for information acquisition and knowledge exchange (IAKE). Social capital is used as a vehicle to explore the relationships between farmers and their advisors using bovine tuberculosis (bTB), a major disease facing the English cattle industry, as a…

Use of SAR in Regional Methane Exchange Studies

NASA Technical Reports Server (NTRS)

Morrissey, L. A.; Livingston, G. P.; Durden, S. L.

1994-01-01

Significant sources of uncertainty in global trace gas budgets are due to lack of knowledge concerning the areal and temporal extent of source and sink areas. Synthetic aperture radar (SAR) is particularly suited to studies of northern ecosystems because of its all-weather operating capability which enables the acquisition of seasonal data. As key controls on methane exchange, the ability to differentiate major vegetation communities, inundation, and leaf area index (LAI) with satellite and airborne SAR data would increase the accuracy and precision of regional and seasonal estimates of methane exchange. The utility of SAR data for monitoring key controls on methane emissions from Arctic and boreal ecosystems is examined.

[International academic mobility program in nursing experience report].

PubMed

de Oliveira, Mariana Gonçalves; Pagliuca, Lorita Marlena Freitag

2012-03-01

An experience of studying abroad or of academic exchange, really adds value to the professional and personal development of exchange students. This report aims to describe a student's experience in an international academic mobility program. It was developed from 2008 to 2009 in Brazil and Spain. The experiences, observations and activities of the student were emphasized believing that the training of students and researchers is not only restricted to the university and the students' home country, and that it is important to have possibilities of new experiences and differentiated knowledge. The conclusion is that this opportunity promoted a profound effect on psychological, cultural social and scientific development of the exchange student.

Knowledge flow and exchange in interdisciplinary primary health care teams (PHCTs): an exploratory study

PubMed Central

Sibbald, Shannon L.; Wathen, C. Nadine; Kothari, Anita; Day, Adam M. B.

2013-01-01

Objective: Improving the process of evidence-based practice in primary health care requires an understanding of information exchange among colleagues. This study explored how clinically oriented research knowledge flows through multidisciplinary primary health care teams (PHCTs) and influences clinical decisions. Methods: This was an exploratory mixed-methods study with members of six PHCTs in Ontario, Canada. Quantitative data were collected using a questionnaire and analyzed with social network analysis (SNA) using UCINet. Qualitative data were collected using semi-structured interviews and analyzed with content analysis procedures using NVivo8. Results: It was found that obtaining research knowledge was perceived to be a shared responsibility among team members, whereas its application in patient care was seen as the responsibility of the team leader, usually the senior physician. PHCT members acknowledged the need for resources for information access, synthesis, interpretation, or management. Conclusion: Information sharing in interdisciplinary teams is a complex and multifaceted process. Specific interventions need to be improved such as formalizing modes of communication, better organizing knowledge-sharing activities, and improving the active use of allied health professionals. Despite movement toward team-based models, senior physicians are often gatekeepers of uptake of new evidence and changes in practice. PMID:23646028

Collaboration with Environmental Protection Administration Taiwan (EPAT)

EPA Pesticide Factsheets

Through this partnership, U.S. and Taiwan environmental authorities have developed a strong capacity to reduce pollution and manage the environment through joint projects, innovate research, and knowledge exchange.

Inelastic neutron scattering cross sections for Ge 76 relevant to background in neutrinoless double- β decay experiments

DOE PAGES

Crider, B. P.; Peters, E. E.; Allmond, J. M.; ...

2015-09-11

The experimental signature in searches for the neutrinoless double- decay of 76Ge is a peak near 2039 keV in the spectrum. Given the low probability of the process, it is important that the background in this region be well understood. Moreover, inelastic scattering reactions with neutrons from muon-induced interactions and ( ,n) reactions in the surrounding materials or in the detector can provide contributions to the background. We also measured the production cross sections for rays from the 76Ge(n,n ) reaction in the 2039-keV region at incident neutron energies up to 4.9 MeV. In addition to determining that the crossmore » sections of a previously known 2040.7-keV ray from the 3952-keV level in 76 Ge are rather small, we find that a larger contribution arises from a 2037.5-keV ray which is attributed to a newly identified level at 3147 keV in 76Ge. Finally, a third contribution is also possible from another new level at 3577 keV. These results indicate that the 2039-keV region in 76Ge neutrinoless double- decay searches is more complex than was previously thought.« less

Mobilizing citizen science to build human and environmental resilience: a synthesis study of four remote mountain communities

NASA Astrophysics Data System (ADS)

Zulkafli, Zed; Buytaert, Wouter; Karpouzoglou, Timothy; Dewulf, Art; Gurung, Praju; Regmi, Santosh; Pandeya, Bhopal; Isaeva, Aiganysh; Mamadalieva, Zuura; Perez, Katya; Alemie, Tilashwork C.; Grainger, Sam; Clark, Julian; Hannah, David M.

2015-04-01

Communities that are the most vulnerable to environmental change and hazards, also tend to be those with the least institutional and financial resilience and capacity to cope with consequent impacts. Relevant knowledge generation is a key requisite for empowering these communities and developing adaptation strategies. Technological innovations in data collection, availability, processing, and exchange, are creating new opportunities for knowledge co-generation that may benefit vulnerable communities and bridge traditional knowledge divides. The use of open, web-based technologies and ICT solutions such as mobile phone apps is particularly promising in this regard, because they allow for participation of communities bypassed by traditional mechanisms. Here, we report on efforts to implement such technologies in a citizen science context. We focus on the active engagement of multiple actors (international and local scientists, government officials, NGOs, community associations, and individuals) in the entire process of the research. This ranges from problem framing, to identifying local monitoring needs, to determining the mode of exchange and forms of knowledge relevant for improving resilience related to water dependency. We present 4 case studies in arid, remote mountain regions of Nepal, the Kyrgyz Republic, Peru, and Ethiopia. In these regions, livelihoods depend on the water and soil systems undergoing accelerated degradation from extreme climates, poor agricultural management practices, and changing environmental conditions. However, information on the interlinkages of these processes with people's livelihoods is typically poor and there lies the opportunity for identifying novel forms of joint-creation and sharing of knowledge. Using a centrally-coordinated but locally-adaptable methodological framework comprising of field visits, systematic reviews of white and grey literature, focus group discussions, household questionnaires, semi-structured interviews, and transect-walks, we identify local knowledge needs related to environmental resources management. The full decision pathways from identifying local knowledge gaps to knowledge co-generation and exchange are presented for all four cases and the similarities and differences between them are highlighted. Our results indicate the existence of several cross-cutting issues, including water availability for crops and livestock as a main driver of environmental poverty and the need for hydro-meteorological information to support local decision-making, as well as the prominent role of traditional systems that are either adaptive or resistive mechanisms to environmental change and resource governance.

[Study on the first translated obstetrics book Tai chan ju yao (Essentials in Obstetrics)].

PubMed

Wu, M

2018-01-28

In 1893, Wan Tsun-mo translated and published Tai chan ju yao ( Essentials in Obstetrics ), the first monograph of western obstetrics in modern China, symbolizing the independence of obstetrics from such maternal and child books as Fu ying xin shuo and Fu ke jing yun tu shuo , which occupies an important position in the history of the development of modern Chinese obstetrics. The book introduced anatomy, physiology, pathology, embryology, diagnostics, surgery, pharmacology and other knowledge of obstetrics in a catechismal form, and had a detailed discussion of such advanced obstetrical technologies as antiseptic, anesthesia, forceps and cesarean section for the first time.Judging from the content and translation of Tai chan ju yao , this book has already possessed the basic knowledge system of modern obstetrics, though the translation appeared to be somewhat jerky and not elegant and the terminology needing to be further improved, it was not only used as an important medium for the introduction of obstetrical knowledge, but also of great clinical value.However, its influence was so weak that later researchers seldom mentioned this book.

X-ray polarimetry. [aboard Ariel 5 and OSO 8 for observation of galactic sources

NASA Technical Reports Server (NTRS)

Long, K. S.; Chanan, G. A.; Helfand, D. J.; Ku, W. H.-M.; Novick, R.

1979-01-01

The method by which the Bragg-crystal X-ray polarimeters aboard Ariel 5 and OSO 8 operate is briefly described, and some results obtained with these instruments for six Galactic X-ray sources are summarized. A precision measurement of the linear polarization in the Crab Nebula at energies of 2.6 and 5.2 keV is presented. Evidence is given for polarization in Sco X-1, Cyg X-2, Cen X-3, and the X-ray transient A0620-00. The determined or estimated polarizations are approximately 19.2% at 2.6 keV and 19.5% at 5.2 keV for the Crab Nebula, 1.1% at 2.6 keV and 2.4% at 5.2 keV for Sco X-1, 2.5% at 2.6 keV and 9.8% at 5.2 keV for Cyg X-1, an upper limit of 13.5% for A0620-00, an upper limit of 13.5% to the time-averaged polarization of Cen X-3, and an apparent value of about 5% for Cyg X-2.

Measurement of the strengths of the resonances at 417, 458, 611, 632 and 1222 keV in the 22Ne(p, γ)23Na reaction

NASA Astrophysics Data System (ADS)

Ferraro, Federico

2018-01-01

The 22Ne(p, γ)23Na reaction is part of the NeNa cycle of hydrogen burning. This cycle plays a key role in the nucleosynthesis of the elements between 20Ne and 27Al in red giant stars, asymptotic giant stars and classical nova explosions. The strengths of the resonances at proton energies above 400 keV are still affected by high uncertainty. In order to reduce this uncertainty, a precision study of some of the most intense resonances between 400 keV and 1250 keV has been performed at the HZDR 3 MV Tandetron. The target, made of 22Ne implanted in a 0.22 mm thick Ta backing, has been characterized using the 1222 keV and 458 keV resonances, well known in literature. Subsequently, the strengths of the resonances at 417, 458, 611, 632 and 1222 keV were determined. Two HPGe detectors equipped with active anti-Compton shielding have been used.

Reclaiming food security in the Mohawk community of Kahnawà:ke through Haudenosaunee responsibilities.

PubMed

Delormier, Treena; Horn-Miller, Kahente; McComber, Alex M; Marquis, Kaylia

2017-11-01

Indigenous Peoples are reclaiming their food security, nutrition, and well-being by revitalizing food systems, livelihoods, knowledge-systems, and governance. Our food security research is guided by sustainable self-determination that focuses on restoring Indigenous cultural responsibilities and relationships to land, each other, and the natural world (Corntassel, 2008). Our Kanien'kehá:ka (Mohawk) research team from Kahnawà:ke, in Quebec, Canada, examines food insecurity experiences in our community to explore ways of upholding our Haudenosaunee responsibilities and enhancing local food security. We collaboratively designed the study and interviewed Kahnawakehró:non (people from the Kahnawake community) with traditional knowledge, extensive community experience, and interests in food and culture. Interviews were audio-recorded, transcribed, and analysed by the team. Analysis characterized food insecurity experiences and conditions that challenge and enable food security with attention to traditional food systems, relationships to land, and gender-related responsibilities. Findings show that communal responsibilities generate resilient strategies that provide for all in times of crisis, and long-term food insecurity is managed through social programs, organized charities, and family support. Enhancing food security involves healing and protecting a limited land-base for food production, integrating food production with community priorities for education, training, health, economic development, and scientific innovation. Nurturing spiritual connections with tionhnhéhkwen (life sustaining foods), the natural world, and each other calls for accelerated teaching and practicing our original instructions. Challenges in developing food security leadership, balancing capitalism and subsistence economies, and strengthening social relationships are rooted in the historical colonial and current settler-colonial context that disrupts all aspects of Kanien'kehá:ka society. © 2018 John Wiley & Sons Ltd.

Enhancing Natural Killer Cell Mediated Targeting and Responses to Myeloid Leukemias

DTIC Science & Technology

2017-10-01

Syndromes , AML – Acute Myeloid Leukemia, BiKE – Bi-specific Killer Engager, TriKE – Tri-specific Killer E 16. SECURITY CLASSIFICATION OF: 17...Natural Killer CML – Chronic Myeloid Leukemia MDS – Myelodysplastic Syndromes AML – Acute Myeloid Leukemia BiKE – Bi-specific Killer Engager TriKE...incidence of myeloid malignancies is increased due to exposure to ionizing radiation , chemicals, and other agents during deployment. Although

Social network analysis of multi-stakeholder platforms in agricultural research for development: Opportunities and constraints for innovation and scaling

PubMed Central

Hermans, Frans; Sartas, Murat; van Schagen, Boudy; van Asten, Piet

2017-01-01

Multi-stakeholder platforms (MSPs) are seen as a promising vehicle to achieve agricultural development impacts. By increasing collaboration, exchange of knowledge and influence mediation among farmers, researchers and other stakeholders, MSPs supposedly enhance their ‘capacity to innovate’ and contribute to the ‘scaling of innovations’. The objective of this paper is to explore the capacity to innovate and scaling potential of three MSPs in Burundi, Rwanda and the South Kivu province located in the eastern part of Democratic Republic of Congo (DRC). In order to do this, we apply Social Network Analysis and Exponential Random Graph Modelling (ERGM) to investigate the structural properties of the collaborative, knowledge exchange and influence networks of these MSPs and compared them against value propositions derived from the innovation network literature. Results demonstrate a number of mismatches between collaboration, knowledge exchange and influence networks for effective innovation and scaling processes in all three countries: NGOs and private sector are respectively over- and under-represented in the MSP networks. Linkages between local and higher levels are weak, and influential organisations (e.g., high-level government actors) are often not part of the MSP or are not actively linked to by other organisations. Organisations with a central position in the knowledge network are more sought out for collaboration. The scaling of innovations is primarily between the same type of organisations across different administrative levels, but not between different types of organisations. The results illustrate the potential of Social Network Analysis and ERGMs to identify the strengths and limitations of MSPs in terms of achieving development impacts. PMID:28166226

Simulations of phase space distributions of storm time proton ring current

NASA Technical Reports Server (NTRS)

Chen, Margaret W.; Lyons, Larry R.; Schulz, Michael

1994-01-01

We use results of guiding-center simulations of ion transport to map phase space densities of the stormtime proton ring current. We model a storm as a sequence of substorm-associated enhancements in the convection electric field. Our pre-storm phase space distribution is an analytical solution to a steady-state transport model in which quiet-time radial diffusion balances charge exchange. This pre-storm phase space spectra at L approximately 2 to 4 reproduce many of the features found in observed quiet-time spectra. Using results from simulations of ion transport during model storms having main phases of 3, 6, and 12 hr, we map phase space distributions from the pre-storm distribution in accordance with Liouville's theorem. We find stormtime enhancements in the phase space densities at energies E approximately 30-160 keV for L approximately 2.5 to 4. These enhancements agree well with the observed stormtime ring current. For storms with shorter main phases (approximately 3 hr), the enhancements are caused mainly by the trapping of ions injected from open night side trajectories, and diffusive transport of higher-energy (greater than or approximately 160 keV) ions contributes little to the stormtime ring current. However, the stormtime ring current is augmented also by the diffusive transport of higher-energy ions (E greater than or approximately 160 keV) durinng stroms having longer main phases (greater than or approximately 6 hr). In order to account for the increase in Dst associated with the formation of the stormtime ring current, we estimate the enhancement in particle-energy content that results from stormtime ion transport in the equatorial magnetosphere. We find that transport alone cannot account for the entire increase in absolute value of Dst typical of a major storm. However, we can account for the entire increase in absolute value of Dst by realistically increasing the stormtime outer boundary value of the phase space density relative to the quiet-time value. We compute the magnetic field produced by the ring current itself and find that radial profiles of the magnetic field depression resemble those obtained from observational data.

Deduction of the rates of radial diffusion of protons from the structure of the Earth's radiation belts

NASA Astrophysics Data System (ADS)

Kovtyukh, Alexander S.

2016-11-01

From the data on the fluxes and energy spectra of protons with an equatorial pitch angle of α0 ≈ 90° during quiet and slightly disturbed (Kp ≤ 2) periods, I directly calculated the value DLL, which is a measure of the rate of radial transport (diffusion) of trapped particles. This is done by successively solving the systems (chains) of integrodifferential equations which describe the balance of radial transport/acceleration and ionization losses of low-energy protons of the stationary belt. This was done for the first time. For these calculations, I used data of International Sun-Earth Explorer 1 (ISEE-1) for protons with an energy of 24 to 2081 keV at L = 2-10 and data of Explorer-45 for protons with an energy of 78.6 to 872 keV at L = 2-5. Ionization losses of protons (Coulomb losses and charge exchange) were calculated on the basis of modern models of the plasmasphere and the exosphere. It is shown that for protons with μ from ˜ 0.7 to ˜ 7 keV nT-1 at L ≈ 4.5-10, the functions of DLL can be approximated by the following equivalent expressions: DLL ≈ 4.9 × 10-14μ-4.1L8.2 or DLL ≈ 1.3 × 105(EL)-4.1 or DLL ≈ 1.2 × 10-9fd-4.1, where fd is the drift frequency of the protons (in mHz), DLL is measured in s-1, E is measured in kiloelectronvolt and μ is measured in kiloelectronvolt per nanotesla. These results are consistent with the radial diffusion of particles under the action of the electric field fluctuations (pulsations) in the range of Pc6 and contradict the mechanism of the radial diffusion of particles under the action of sudden impulses (SIs) of the magnetic field and also under the action of substorm impulses of the electric field. During magnetic storms DLL increases, and the expressions for DLL obtained here can change completely.

Retrieval of ion distributions in RC from TWINS ENA images by CT technique

NASA Astrophysics Data System (ADS)

Ma, S.; Yan, W.; Xu, L.; Goldstein, J.; McComas, D. J.

2010-12-01

The Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) mission is the first constellation to employ imagers on two separate spacecraft to measure energetic neutral atoms (ENA) produced by charge exchange between ring current energetic ions and cold exospheric neutral atoms. By applying the 3-D volumetric pixel (voxel) computed tomography (CT) inversion method to TWINS images, parent ion populations in the ring current (RC) and auroral regions are retrieved from their ENA signals. This methodology is implemented for data obtained during the main phase of a moderate geomagnetic storm on 11 October 2008. For this storm the two TWINS satellites were located in nearly the same meridian plane at vantage points widely separated in magnetic local time, and both more than 5 RE geocentric distance from the Earth. In the retrieval process, the energetic ion fluxes to be retrieved are assumed being isotropic with respect to pitch angle. The ENA data used in this study are differential fluxes averaged over 12 sweeps (corresponding to an interval of 16 min.) at different energy levels ranging throughout the full 1--100 keV energy range of TWINS. The ENA signals have two main components: (1) a low-latitude/ high-altitude signal from trapped RC ions and (2) a low-altitude signal from precipitating ions in the auroral/subauroral ionosphere. In the retrieved ion distributions, the main part of the RC component is located around midnight toward dawn sector with L from 3 to 7 or farther, while the subauroral low-altitude component is mainly at pre-midnight. It seems that the dominant energy of the RC ions for this storm is at the lowest energy level of 1-2 keV, with another important energy band centered about 44 keV. The low-altitude component is consistent with in situ observations by DMSP/SSJ4. The result of this study demonstrates that with satellite constellations such as TWINS, using all-sky ENA imagers deployed at multiple vantage points, 3-D distribution of RC ion intensity may be reconstructed via the CT technique. Acknowledgement: This work is supported by NSFC (Grant No. 40674078).

Probing the Martian Exosphere and Neutral Escape Using Pickup Ions Measured by MAVEN

NASA Astrophysics Data System (ADS)

Rahmati, A.; Larson, D. E.; Cravens, T.; Halekas, J. S.; Lillis, R. J.; McFadden, J. P.; Mitchell, D. L.; Thiemann, E.; Connerney, J. E. P.; Dunn, P.; DiBraccio, G. A.; Espley, J. R.; Eparvier, F. G.; Jakosky, B. M.

2016-12-01

Soon after the MAVEN (Mars Atmosphere and Volatile EvolutioN) spacecraft started orbiting Mars in September 2014, the SEP (Solar Energetic Particle), SWIA (Solar Wind Ion Analyzer), and STATIC (Supra-Thermal and Thermal Ion Composition) instruments onboard the spacecraft started detecting planetary pickup ions. SEP can measure energetic (>50 keV) oxygen pickup ions, the source of which is the extended hot oxygen exosphere of Mars. Model results show that these pickup ions originate from tens of Martian radii upstream of Mars and are energized by the solar wind motional electric field as they gyrate back towards Mars. SEP is blind to pickup hydrogen, as the low energy threshold for detection of hydrogen in SEP is 20 keV; well above the maximum pickup hydrogen energy, which is four times the solar wind proton energy. SWIA and STATIC, on the other hand, can detect both pickup oxygen and pickup hydrogen with energies below 30 keV and created closer to Mars. During the times when MAVEN is outside the Martian bow shock and in the upstream undisturbed solar wind, the solar wind velocity measured by SWIA and the solar wind (or interplanetary) magnetic field measured by the MAG (magnetometer) instrument can be used to model pickup oxygen and hydrogen fluxes near Mars. Solar wind flux measurements of the SWIA instrument are used in calculating charge-exchange frequencies, and data from the EUVM (Extreme Ultraviolet Monitor) and SWEA (Solar Wind Electron Analyzer) instruments are also used in calculating photo-ionization and electron impact frequencies of neutral species in the Martian exosphere. By comparing SEP, SWIA, and STATIC measured pickup ion fluxes with model results, the Martian thermal hydrogen and hot oxygen neutral densities can be probed outside the bow shock, which would place constraints on estimates of oxygen and hydrogen neutral escape rates. We will present model-data comparisons of pickup ions measured outside the Martian bow shock. Our analysis reveals an order of magnitude density change with Mars season in the hydrogen exosphere, whereas the hot oxygen exosphere densities vary less than a factor of 2.

The magnetic local time distribution of energetic electrons in the radiation belt region

NASA Astrophysics Data System (ADS)

Allison, Hayley J.; Horne, Richard B.; Glauert, Sarah A.; Zanna, Giulio Del

2017-08-01

Using 14 years of electron flux data from the National Oceanic and Atmospheric Administration Polar Operational Environmental Satellites, a statistical study of the magnetic local time (MLT) distribution of the electron population is performed across a range of activity levels, defined by AE, AE*, Kp, solar wind velocity (Vsw), and VswBz. Three electron energies (>30, >100, and >300 keV) are considered. Dawn-dusk flux asymmetries larger than order of magnitude were observed for >30 and >100 keV electrons. For >300 keV electrons, dawn-dusk asymmetries were primarily due to a decrease in the average duskside flux beyond L* ˜ 4.5 that arose with increasing activity. For the >30 keV population, substorm injections enhance the dawnside flux, which may not reach the duskside as the electrons can be on open drift paths and lost to the magnetopause. The asymmetries in the >300 keV population are attributed to the combination of magnetopause shadowing and >300 keV electron injections by large electric fields. We suggest that 3-D radiation belt models could set the minimum energy boundary (Emin) to 30 keV or above at L* ˜ 6 during periods of low activity. However, for more moderate conditions, Emin should be larger than 100 keV and, for very extreme activities, ˜300 keV. Our observations show the extent that in situ electron flux readings may vary during active periods due to the MLT of the satellite and highlight the importance of 4-D radiation belt models to fully understand radiation belt processes.

The Magnetic Local Time Distribution of Energetic Electrons in the Radiation Belt Region

NASA Astrophysics Data System (ADS)

Allison, H. J.

2017-12-01

Using fourteen years of electron flux data from the National Oceanic and Atmospheric Administration Polar Operational Environmental Satellites (POES), a statistical study of the magnetic local time (MLT) distribution of the electron population is performed across a range of activity levels, defined by AE, AE*, Kp, solar wind velocity (Vsw), and VswBz. Three electron energies (>30, >100, and >300 keV) are considered. Dawn-dusk flux asymmetries larger than order of magnitude were observed for >30 and >100 keV electrons. For >300 keV electrons, dawn-dusk asymmetries were primarily due to a decrease in the average dusk-side flux beyond L* ˜ 4.5 that arose with increasing activity. For the >30 keV population, substorm injections enhance the dawn-side flux, which may not reach the dusk-side as the electrons can be on open drift paths and lost to the magnetopause. The asymmetries in the >300 keV population are attributed to the combination of magnetopause shadowing and >300 keV electron injections by large electric fields. We suggest that 3D radiation belt models could set the minimum energy boundary (Emin) to 30 keV or above at L* ˜6 during periods of low activity. However, for more moderate conditions, Emin should be larger than 100 keV and, for very extreme activities, ˜300 keV. Our observations show the extent that in-situ electron flux readings may vary during active periods due to the MLT of the satellite and highlight the importance of 4D radiation belt models to fully understand radiation belt processes.

Transforming Classroom Music Instruction with Ideas from Critical Pedagogy: Teachers and Students Can Learn from Each Other when They Use Lesson Plans that Encourage an Exchange of Knowledge

ERIC Educational Resources Information Center

Abrahams, Frank

2005-01-01

Paulo Freire developed critical pedagogy in Brazil in the 1960s to teach illiterate adults (or, as Freire calls them, "the oppressed") to read. Freire believed that teaching was a conversational exchange of information between the teacher and the student. He posed questions and problems to his students that caused them to take what they already…

Defence SDI - A Useful Current Awareness System (Dissemination Selective de L’Information sur la Defense: Un Systeme Pratique D’Information Permanente).

DTIC Science & Technology

1980-09-01

OF SCIENTIFIC INFORMATION SERVICES L EFENCE SDI - A USEFUL CURRENT AWARENESS SYSTEM (Dissemination Selective de L’Information, Sur la Defense: Un...Dalhousie University, Halifax, Nova Scotia. CAUTION This information is furnished with the express understanding that proprietary and patent rights will be...may add his knowledge of information exchange agreements and Canadian projects covered by these agreements. These exchange agreements are important