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Sample records for ev postionization mass

  1. Laser Desorption Postionization Mass Spectrometry of Antibiotic-Treated Bacterial Biofilms using Tunable Vacuum Ultraviolet Radiation

    SciTech Connect

    Gasper, Gerald L; Takahashi, Lynelle K; Zhou, Jia; Ahmed, Musahid; Moore, Jerry F; Hanley, Luke

    2010-08-04

    Laser desorption postionization mass spectrometry (LDPI-MS) with 8.0 ? 12.5 eV vacuum ultraviolet synchrotron radiation is used to single photon ionize antibiotics andextracellular neutrals that are laser desorbed both neat and from intact bacterial biofilms. Neat antibiotics are optimally detected using 10.5 eV LDPI-MS, but can be ionized using 8.0 eV radiation, in agreement with prior work using 7.87 eV LDPI-MS. Tunable vacuum ultraviolet radiation also postionizes laser desorbed neutrals of antibiotics and extracellular material from within intact bacterial biofilms. Different extracellular material is observed by LDPI-MS in response to rifampicin or trimethoprim antibiotic treatment. Once again, 10.5 eV LDPI-MS displays the optimum trade-off between improved sensitivity and minimum fragmentation. Higher energy photons at 12.5 eV produce significant parent ion signal, but fragment intensity and other low mass ions are also enhanced. No matrix is added to enhance desorption, which is performed at peak power densities insufficient to directly produce ions, thus allowing observation of true VUV postionization mass spectra of antibiotic treated biofilms.

  2. Laser Desorption Postionization Mass Spectrometry of Antibiotic-Treated Bacterial Biofilms using Tunable Vacuum Ultraviolet Radiation

    PubMed Central

    Gasper, Gerald L.; Takahashi, Lynelle K.; Zhou, Jia; Ahmed, Musahid; Moore, Jerry F.; Hanley, Luke

    2010-01-01

    Laser desorption postionization mass spectrometry (LDPI-MS) with 8.0 – 12.5 eV vacuum ultraviolet synchrotron radiation is used to single photon ionize antibiotics and extracellular neutrals that are laser desorbed both neat and from intact bacterial biofilms. Neat antibiotics are optimally detected using 10.5 eV LDPI-MS, but can be ionized using 8.0 eV radiation, in agreement with prior work using 7.87 eV LDPI-MS. Tunable vacuum ultraviolet radiation also postionizes laser desorbed neutrals of antibiotics and extracellular material from within intact bacterial biofilms. Different extracellular material is observed by LDPI-MS in response to rifampicin or trimethoprim antibiotic treatment. Once again, 10.5 eV LDPI-MS displays the optimum trade-off between improved sensitivity and minimum fragmentation. Higher energy photons at 12.5 eV produce significant parent ion signal, but fragment intensity and other low mass ions are also enhanced. No matrix is added to enhance desorption, which is performed at peak power densities insufficient to directly produce ions, thus allowing observation of true VUV postionization mass spectra of antibiotic treated biofilms. PMID:20712373

  3. Brominated Tyrosine and Polyelectrolyte Multilayer Analysis by Laser Desorption VUV Postionization and Secondary Ion Mass Spectrometry

    PubMed Central

    Melvin Blaze, M.T.; Takahashi, Lynelle K.; Zhou, Jia; Ahmed, Musahid; Gasper, Gerald L.; Pleticha, F. Douglas; Hanley, Luke

    2011-01-01

    The small molecular analyte 3,5-dibromotyrosine (Br2Y) and chitosan-alginate polyelectrolyte multilayers (PEM) with and without adsorbed Br2Y were analyzed by laser desorption postionization mass spectrometry (LDPI-MS). LDPI-MS using 7.87 eV laser and tunable 8 – 12.5 eV synchrotron vacuum ultraviolet (VUV) radiation found that desorption of clusters from Br2Y films allowed detection by ≤8 eV single photon ionization. Thermal desorption and electronic structure calculations determined the ionization energy of Br2Y to be ~8.3±0.1 eV and further indicated that the lower ionization energies of clusters permitted their detection at ≤8 eV photon energies. However, single photon ionization could only detect Br2Y adsorbed within PEMs when using either higher photon energies or matrix addition to the sample. All samples were also analyzed by 25 keV Bi3+ secondary ion mass spectrometry (SIMS), with the negative ion spectra showing strong parent ion signal which complemented that observed by LDPI-MS. However, the negative ion SIMS appeared strongly dependent on the high electron affinity of this specific analyte and the analyte’s condensed phase environment. PMID:21548612

  4. Brominated Tyrosine and Polyelectrolyte Multilayer Analysis by Laser Desorption VUV Postionization and Secondary Ion Mass Spectrometry

    SciTech Connect

    University of Illinois at Chicago; Blaze, Melvin M. T.; Takahashi, Lynelle; Zhou, Jia; Ahmed, Musahid; Gasper, Gerald; Pleticha, F. Douglas; Hanley, Luke

    2011-03-14

    The small molecular analyte 3,5-dibromotyrosine (Br2Y) and chitosan-alginate polyelectrolyte multilayers (PEM) with and without adsorbed Br2Y were analyzed by laser desorption postionization mass spectrometry (LDPI-MS). LDPI-MS using 7.87 eV laser and tunable 8 ? 12.5 eV synchrotron vacuum ultraviolet (VUV) radiation found that desorption of clusters from Br2Y films allowed detection by≤8 eV single photon ionization. Thermal desorption and electronic structure calculations determined the ionization energy of Br2Y to be ~;;8.3?0.1 eV and further indicated that the lower ionization energies of clusters permitted their detection at≤8 eV photon energies. However, single photon ionization could only detect Br2Y adsorbed within PEMs when using either higher photon energies or matrix addition to the sample. All samples were also analyzed by 25 keV Bi3 + secondary ion mass spectrometry (SIMS), with the negative ion spectra showing strong parent ion signal which complemented that observed by LDPI-MS. The negative ion SIMS depended strongly on the high electron affinity of this specific analyte and the analyte?s condensed phase environment.

  5. Differentiation of Microbial Species and Strains in Coculture Biofilms by Multivariate Analysis of Laser Desorption Postionization Mass Spectra

    PubMed Central

    Bhardwaj, Chhavi; Cui, Yang; Hofstetter, Theresa; Liu, Suet Yi; Bernstein, Hans C.; Carlson, Ross P.; Ahmed, Musahid; Hanley, Luke

    2013-01-01

    7.87 to 10.5 eV vacuum ultraviolet (VUV) photon energies were used in laser desorption postionization mass spectrometry (LDPI-MS) to analyze biofilms comprised of binary cultures of interacting microorganisms. The effect of photon energy was examined using both tunable synchrotron and laser sources of VUV radiation. Principal components analysis (PCA) was applied to the MS data to differentiate species in Escherichia coli-Saccharomyces cerevisiae coculture biofilms. PCA of LDPI-MS also differentiated individual E. coli strains in a biofilm comprised of two interacting gene deletion strains, even though these strains differed from the wild type K-12 strain by no more than four gene deletions each out of approximately 2000 genes. PCA treatment of 7.87 eV LDPI-MS data separated the E. coli strains into three distinct groups, two “pure” groups, and a mixed region. Furthermore, the “pure” regions of the E. coli cocultures showed greater variance by PCA at 7.87 eV photon energies compared to 10.5 eV radiation. This is consistent with the expectation that the 7.87 eV photoionization selects a subset of low ionization energy analytes while 10.5 eV is more inclusive, detecting a wider range of analytes. These two VUV photon energies therefore give different spreads via PCA and their respective use in LDPI-MS constitute an additional experimental parameter to differentiate strains and species. PMID:24067765

  6. Differentiation of Microbial Species and Strains in Coculture Biofilms by Multivariate Analysis of Laser Desorption Postionization Mass Spectra

    SciTech Connect

    University of Illinois at Chicago; Montana State University; Bhardwaj, Chhavi; Cui, Yang; Hofstetter, Theresa; Liu, Suet Yi; Bernstein, Hans C.; Carlson, Ross P.; Ahmed, Musahid; Hanley, Luke

    2013-04-01

    7.87 to 10.5 eV vacuum ultraviolet (VUV) photon energies were used in laser desorption postionization mass spectrometry (LDPI-MS) to analyze biofilms comprised of binary cultures of interacting microorganisms. The effect of photon energy was examined using both tunable synchrotron and laser sources of VUV radiation. Principal components analysis (PCA) was applied to the MS data to differentiate species in Escherichia coli-Saccharomyces cerevisiae coculture biofilms. PCA of LDPI-MS also differentiated individual E. coli strains in a biofilm comprised of two interacting gene deletion strains, even though these strains differed from the wild type K-12 strain by no more than four gene deletions each out of approximately 2000 genes. PCA treatment of 7.87 eV LDPI-MS data separated the E. coli strains into three distinct groups two ?pure? groups and a mixed region. Furthermore, the ?pure? regions of the E. coli cocultures showed greater variance by PCA when analyzed by 7.87 eV photon energies than by 10.5 eV radiation. Comparison of the 7.87 and 10.5 eV data is consistent with the expectation that the lower photon energy selects a subset of low ionization energy analytes while 10.5 eV is more inclusive, detecting a wider range of analytes. These two VUV photon energies therefore give different spreads via PCA and their respective use in LDPI-MS constitute an additional experimental parameter to differentiate strains and species.

  7. Laser desorption postionization mass spectrometry imaging of biological targets.

    PubMed

    Akhmetov, Artem; Bhardwaj, Chhavi; Hanley, Luke

    2015-01-01

    Laser desorption photoionization mass spectrometry (LDPI-MS) utilizes two separate light sources for desorption and photoionization of species from a solid surface. This technique has been applied to study a wide variety of molecular analytes in biological systems, but is not yet available in commercial instruments. For this reason, a generalized protocol is presented here for the use of LDPI-MS imaging to detect small molecules within intact biological samples. Examples are provided here for LDPI-MS imaging of an antibiotic within a tooth root canal and a metabolite within a coculture bacterial biofilm. PMID:25361678

  8. High-repetition rate laser ablation coupled to dielectric barrier discharge postionization for ambient mass spectrometry.

    PubMed

    Bierstedt, Andreas; Riedel, Jens

    2016-07-15

    Most ambient sample introduction and ionization techniques for native mass spectrometry are highly selective for polar agents. To achieve a more general sensitivity for a wider range of target analytes, a novel laser ablation dielectric barrier discharge (LA DBD) ionization scheme was developed. The approach employs a two-step mechanism with subsequent sample desorption and post-ionization. Effective ablation was achieved by the second harmonic output (λ=532nm) of a diode pumped Nd:YVO4 laser operating at a high-repetition rate of several kHz and pulse energies below 100μJ. The ejected analyte-containing aerosol was consecutively vaporized and ionized in the afterglow of a DBD plasma jet. Depending on their proton affinity the superexcited helium species in this afterglow produced analyte ions as protonated and ammoniated species, as well as radical cations. The optimization procedure could corroborate underlying conceptual consideration on the ablation, desorption and ionization mechanisms. A successful detection of a variety of target molecules could be shown from the pharmaceutical ibuprofen, urea, the amino acids l-arginine, l-lysine, the polymer polyethylene glycol, the organometallic compound ferrocene and the technical mixture wild mint oil. For a reliable evaluation of the introduced detection procedure spectra from the naturally abundant alkaloid capsaicin in dried capsicum fruits were recorded. PMID:26851554

  9. Laser Post-Ionization Mass Spectrometry Analysis of Genesis Solar Wind Collectors

    NASA Astrophysics Data System (ADS)

    Veryovkin, I. V.; Tripa, C. E.; Zinovev, A. V.; Hiller, J. M.; Pellin, M. J.; Burnett, D. S.

    2008-12-01

    The samples returned to Earth by the NASA's Genesis Mission contain a record of the elemental and isotopic abundances of the Solar Wind (SW). This record is formed by the SW ions implanted in the near-surface regions of the Genesis sample collectors, so that the SW material can be distinguished from a terrestrial contamination, which occurred due to the crash landing of the spacecraft Sample Return Capsule. At Argonne National Laboratory, we are conducting analyzes of the Genesis SW collectors using a specially developed Laser Post-Ionization Secondary Neutral Mass Spectrometer (LPI SNMS), SARISA. This approach, based on ion sputtering of a SW collector surface and laser post-ionization of the neutral atoms sputtered from it, has proved to be sensitive, accurate and well suited for the quantitative analysis of the Genesis samples. We will report in this work the abundances of SW Mg and Ca measured with SARISA in two types of SW collector materials, silicon and diamond-like carbon (DLC). These LPI SNMS measurements were conducted in Resonance-Enhanced Multi-Photon Ionization (REMPI) regime using a sputter depth profiling method. In order to make our analyzes quantitative, we used specially prepared standards, made from exactly the same materials as the flown Genesis SW collectors and implanted with known fluencies of Mg and Ca ions. The REMPI analyzes of these standards allowed us to characterize the actual efficiency and detection limits of the SARISA instrument: for Mg, its useful yield peaked at about 20% and detection limits corresponded to < 50 part-per-trillion. We measured concentration vs depth profiles for Mg and Ca in SW collectors (Si and DLC, respectively) and compared them to the corresponding implant standards. One striking feature of the SW implants (compared to the standards) was that maxima of the SW element concentration vs depth profiles were broad, with apparent diffusion of the implanted atoms towards the surface and into the bulk. Since these

  10. Comparing Vacuum and Extreme Ultraviolet Radiation for Postionization of Laser Desorbed Neutrals from Bacterial Biofilms and Organic Fullerene

    SciTech Connect

    Gaspera, Gerald L.; Takahashi, Lynelle K.; Zhou, Jia; Ahmed, Musahid; Moored, Jerry F.; Hanley, Luke

    2010-12-08

    Vacuum and extreme ultraviolet radiation from 8 - 24 eV generated at a synchrotron was used to postionize laser desorbed neutrals of antibiotic-treated biofilms and a modified fullerene using laser desorption postionization mass spectrometry (LDPI-MS). Results show detection of the parent ion, various fragments, and extracellular material from biofilms using LDPI-MS with both vacuum and extreme ultraviolet photons. Parent ions were observed for both cases, but extreme ultraviolet photons (16-24 eV) induced more fragmentation than vacuum ultraviolet (8-14 eV) photons.

  11. Laser post-ionization secondary neutral mass spectrometry for ultra-trace analysis of samples from space return missions

    NASA Astrophysics Data System (ADS)

    Veryovkin, Igor V.; Calaway, Wallis F.; Emil Tripa, C.; Moore, Jerry F.; Wucher, Andreas; Pellin, Michael J.

    2005-12-01

    A new generation of secondary neutral mass spectrometry (SNMS) instruments has been developed that is especially designed for laser post-ionization (LPI). These instruments combine high useful yield and high background discrimination. Results presented here demonstrate that these instruments can detect one in every four atoms removed from a samples surface - a greater than one order of magnitude improvement over current large frame secondary ion mass spectrometry instruments. Because of their high sensitivity, these new LPI-SNMS instruments are especially amenable to analysis of samples of limited size and rare one-of-a-kind samples. Such an application is analysis of samples returned to Earth from space by the Genesis and Stardust Discovery missions of NASA.

  12. Ambient Molecular Analysis of Biological Tissue Using Low-Energy, Femtosecond Laser Vaporization and Nanospray Postionization Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Shi, Fengjian; Flanigan, Paul M.; Archer, Jieutonne J.; Levis, Robert J.

    2016-03-01

    Direct analysis of plant and animal tissue samples by laser electrospray mass spectrometry (LEMS) was investigated using low-energy, femtosecond duration laser vaporization at wavelengths of 800 and 1042 nm followed by nanospray postionization. Low-energy (<50 μJ), fiber-based 1042 nm LEMS (F-LEMS) allowed interrogation of the molecular species in fresh flower petal and leaf samples using 435 fs, 10 Hz bursts of 20 pulses from a Ytterbium-doped fiber laser and revealed comparable results to high energy (75-1120 μJ), 45 fs, 800 nm Ti:Sapphire-based LEMS (Ti:Sapphire-LEMS) measurements. Anthocyanins, sugars, and other metabolites were successfully detected and revealed the anticipated metabolite profile for the petal and leaf samples. Phospholipids, especially phosphatidylcholine, were identified from a fresh mouse brain section sample using Ti:Sapphire-LEMS without the application of matrix. These lipid features were suppressed in both the fiber-based and Ti:Sapphire-based LEMS measurements when the brain sample was prepared using the optimal cutting temperature compounds that are commonly used in animal tissue cryosections.

  13. Ambient Molecular Analysis of Biological Tissue Using Low-Energy, Femtosecond Laser Vaporization and Nanospray Postionization Mass Spectrometry.

    PubMed

    Shi, Fengjian; Flanigan, Paul M; Archer, Jieutonne J; Levis, Robert J

    2016-03-01

    Direct analysis of plant and animal tissue samples by laser electrospray mass spectrometry (LEMS) was investigated using low-energy, femtosecond duration laser vaporization at wavelengths of 800 and 1042 nm followed by nanospray postionization. Low-energy (<50 μJ), fiber-based 1042 nm LEMS (F-LEMS) allowed interrogation of the molecular species in fresh flower petal and leaf samples using 435 fs, 10 Hz bursts of 20 pulses from a Ytterbium-doped fiber laser and revealed comparable results to high energy (75-1120 μJ), 45 fs, 800 nm Ti:Sapphire-based LEMS (Ti:Sapphire-LEMS) measurements. Anthocyanins, sugars, and other metabolites were successfully detected and revealed the anticipated metabolite profile for the petal and leaf samples. Phospholipids, especially phosphatidylcholine, were identified from a fresh mouse brain section sample using Ti:Sapphire-LEMS without the application of matrix. These lipid features were suppressed in both the fiber-based and Ti:Sapphire-based LEMS measurements when the brain sample was prepared using the optimal cutting temperature compounds that are commonly used in animal tissue cryosections. PMID:26667178

  14. Application of laser postionization secondary neutral mass spectrometry/time-of-flight secondary ion mass spectrometry in nanotoxicology: visualization of nanosilver in human macrophages and cellular responses.

    PubMed

    Haase, Andrea; Arlinghaus, Heinrich F; Tentschert, Jutta; Jungnickel, Harald; Graf, Philipp; Mantion, Alexandre; Draude, Felix; Galla, Sebastian; Plendl, Johanna; Goetz, Mario E; Masic, Admir; Meier, Wolfgang; Thünemann, Andreas F; Taubert, Andreas; Luch, Andreas

    2011-04-26

    Silver nanoparticles (SNP) are the subject of worldwide commercialization because of their antimicrobial effects. Yet only little data on their mode of action exist. Further, only few techniques allow for visualization and quantification of unlabeled nanoparticles inside cells. To study SNP of different sizes and coatings within human macrophages, we introduce a novel laser postionization secondary neutral mass spectrometry (Laser-SNMS) approach and prove this method superior to the widely applied confocal Raman and transmission electron microscopy. With time-of-flight secondary ion mass spectrometry (TOF-SIMS) we further demonstrate characteristic fingerprints in the lipid pattern of the cellular membrane indicative of oxidative stress and membrane fluidity changes. Increases of protein carbonyl and heme oxygenase-1 levels in treated cells confirm the presence of oxidative stress biochemically. Intriguingly, affected phagocytosis reveals as highly sensitive end point of SNP-mediated adversity in macrophages. The cellular responses monitored are hierarchically linked, but follow individual kinetics and are partially reversible. PMID:21456612

  15. Online laser desorption-multiphoton postionization mass spectrometry of individual aerosol particles: molecular source indicators for particles emitted from different traffic-related and wood combustion sources.

    PubMed

    Bente, Matthias; Sklorz, Martin; Streibel, Thorsten; Zimmermann, Ralf

    2008-12-01

    Direct inlet aerosol mass spectrometry plays an increasingly important role in applied and fundamental aerosol and nanoparticle research. Laser desorption/ionization (LDI) based techniques for single particle time-of-flight mass spectrometry (LDI-SP-TOFMS) are a promising approach in the chemical analysis of single aerosol particles, especially for the detection of inorganic species and distinction of particle classes. However, until now the detection of molecular organic compounds on a single particle basis has been difficult due to the high laser power densities which are required for the LDI process as well as due to the inherent matrix effects associated with this ionization technique. By the application of a two-step approach, where an IR desorption laser pulse is applied to perform a gentle desorption of organic material from the single particle surface and a second UV-laser performs the soft ionization of the desorbed species, this drawback of laser based single particles mass spectrometry can be overcome. The postionization of the desorbed molecules has been accomplished in this work by resonance enhanced multiphoton ionization (REMPI) using a KrF excimer laser (248 nm). REMPI allows an almost fragmentation free trace analysis of polycyclic aromatic hydrocarbons (PAHs) and their derivatives from individual single particles (laser desorption-REMPI postionization-single particle-time-of-flight mass spectrometry or LD-REMPI-SP-TOFMS). Crucial system parameters of the home-built aerosol mass spectrometer such as the power densities and the relative timing of both lasers were optimized with respect to the detectability of particle source specific organic signatures using well characterized standard particles. In a second step, the LD-REMPI-SP-TOFMS system was applied to analyze different real world aerosols (spruce wood combustion, gasoline car exhaust, beech wood combustion, and diesel car exhaust). It was possible to distinguish the particles from different

  16. Laser postionization secondary neutral mass spectrometry in tissue: a powerful tool for elemental and molecular imaging in the development of targeted drugs.

    PubMed

    Wittig, Andrea; Arlinghaus, Heinrich F; Kriegeskotte, Christian; Moss, Raymond L; Appelman, Klaas; Schmid, Kurt W; Sauerwein, Wolfgang A G

    2008-07-01

    The exact intracellular localization and distribution of molecules and elements becomes increasingly important for the development of targeted therapies and contrast agents. We show that laser postionization secondary neutral mass spectrometry (laser-SNMS) is well suited to localize particular elements and small molecules with subcellular spatial resolution applying the technique exemplary to Boron Neutron Capture Therapy (BNCT). We showed in a murine sarcoma that the drugs used for clinical BNCT, namely l-para-boronophenylalanine (700 mg/kg body weight i.p.) and sodium mercaptoundecahydro-closo-dodecaborate (200 mg/kg body weight i.p.), transport the therapeutic agent (10)B into the cytoplasm and into the nucleus itself, the most sensitive area of the cell. Sodium mercaptoundecahydro-closo-dodecaborate distributes (10)B homogeneously and l-para-boronophenylalanine heterogeneously. When combining laser-SNMS with prompt gamma-ray analysis as a screening technique, strategies for BNCT can be elaborated to develop new drugs or to improve the use of existing drugs on scientifically based evidence. The study shows the power of laser-SNMS in the early stages of drug development, also outside BNCT. PMID:18644988

  17. Direct analysis of intact biological macromolecules by low-energy, fiber-based femtosecond laser vaporization at 1042 nm wavelength with nanospray postionization mass spectrometry.

    PubMed

    Shi, Fengjian; Flanigan, Paul M; Archer, Jieutonne J; Levis, Robert J

    2015-03-17

    A fiber-based laser with a pulse duration of 435 fs and a wavelength of 1042 nm was used to vaporize biological macromolecules intact from the condensed phase into the gas phase for nanospray postionization and mass analysis. Laser vaporization of dried standard protein samples from a glass substrate by 10 Hz bursts of 20 pulses having 10 μs pulse separation and <50 μJ pulse energy resulted in signal comparable to a metal substrate. The protein signal observed from an aqueous droplet on a glass substrate was negligible compared to either a droplet on metal or a thin film on glass. The mass spectra generated from dried and aqueous protein samples by the low-energy, fiber laser were similar to the results from high-energy (500 μJ), 45-fs, 800-nm Ti:sapphire-based femtosecond laser electrospray mass spectrometry (LEMS) experiments, suggesting that the fiber-based femtosecond laser desorption mechanism involves a nonresonant, multiphoton process, rather than thermal- or photoacoustic-induced desorption. Direct analysis of whole blood performed without any pretreatment resulted in features corresponding to hemoglobin subunit-heme complex ions. The observation of intact molecular ions with low charge states from protein, and the tentatively assigned hemoglobin α subunit-heme complex from blood suggests that fiber-based femtosecond laser vaporization is a "soft" desorption source at a laser intensity of 2.39 × 10(12) W/cm(2). The low-energy, turnkey fiber laser demonstrates the potential of a more robust and affordable laser for femtosecond laser vaporization to deliver biological macromolecules into the gas phase for mass analysis. PMID:25688836

  18. Detection of in-situ derivatized peptides in microbial biofilms by laser desorption 7.87 eV postionizaton mass spectrometry.

    SciTech Connect

    Edirisinghe, P. D.; Moore, J. F.; Skinner-Nemec, K. A.; Lindberg, C.; Giometti, C. S.; Veryovkin, I. V.; Hunt, J. E.; Pellin, M. J.; Hanley, L.; Biosciences Division; Univ. of Illinois at Chicago; MassThink

    2007-01-01

    A novel analytical method based on laser desorption postionization mass spectrometry (LDPI-MS) was developed to investigate the competence and sporulation factor-a pentapeptide of amino acid sequence ERGMT-within intact Bacillus subtilis biofilms. Derivatization of the neat ERGMT peptide with quinoline- and anthracene-based tags was separately used to lower the peptide ionization potential and permit direct ionization by 7.87-eV vacuum ultraviolet radiation. The techniques of mass shifting and selective ionization of the derivatized peptide were combined here to permit detection of ERGMT peptide within intact biofilms by LDPI-MS, without any prior extraction or chromatographic separation. Finally, imaging MS specific to the derivatized peptide was demonstrated on an intact biofilm using LDPI-MS. The presence of ERGMT in the biofilms was verified by bulk extraction/LC-MS. However, MALDI imaging MS analyses were unable to detect ERGMT within intact biofilms.

  19. Nonresonant, femtosecond laser vaporization and electrospray post-ionization mass spectrometry as a tool for biological tissue imaging.

    PubMed

    Shi, Fengjian; Archer, Jieutonne J; Levis, Robert J

    2016-07-15

    An ambient mass spectrometry imaging (MSI) source is demonstrated with both high spatial and mass resolution that enables measurement of the compositional heterogeneity within a biological tissue sample. The source is based on nonresonant, femtosecond laser electrospray mass spectrometry (LEMS) coupled to a quadrupole time-of-flight (QTOF) mass analyzer. No matrix deposition and minimal sample preparation is necessary for the source. The laser, translation stage, and mass spectrometer are synchronized and controlled using a customized user interface. Single or multiple laser shots may be applied to each pixel. A scanning rate of 2.0s per pixel is achieved. Measurement of a patterned ink film indicates the potential of LEMS for ambient imaging with a lateral resolution of ∼60μm. Metabolites including sugar, anthocyanins and other small metabolites were successfully mapped from plant samples without oversampling using a spot size of 60×70μm(2). Molecular identification of the detected analytes from the tissue was enabled by accurate mass measurement in conjunction with tandem mass spectrometry. Statistical analysis, non-negative matrix factorization and principle component analysis, were applied to the imaging data to extract regions with distinct and/or correlated spectral profiles. PMID:26931651

  20. Mass Absorption Coefficient of Tungsten and Tantalum, 1450 eV to 2350 eV: Experiment, Theory, and Application

    PubMed Central

    Levine, Zachary H.; Grantham, Steven; Tarrio, Charles; Paterson, David J.; McNulty, Ian; Levin, T. M.; Ankudinov, Alexei L.; Rehr, John J.

    2003-01-01

    The mass absorption coefficients of tungsten and tantalum were measured with soft x-ray photons from 1450 eV to 2350 eV using an undulator source. This region includes the M3, M4, and M5 absorption edges. X-ray absorption fine structure was calculated within a real-space multiple scattering formalism; the predicted structure was observed for tungsten and to a lesser degree tantalum as well. Separately, the effects of dynamic screening were observed as shown by an atomic calculation within the relativistic time-dependent local-density approximation. Dynamic screening effects influence the spectra at the 25 % level and are observed for both tungsten and tantalum. We applied these results to characterize spatially-resolved spectra of a tungsten integrated circuit interconnect obtained using a scanning transmission x-ray microscope. The results indicate tungsten fiducial markers were deposited into silica trenches with a depths of 50 % and 60 % of the markers’ heights.

  1. a Mechanistic View of the Ion/solid Interaction Using Laser Postionization, Time-Of Mass Spectrometry, and Molecular Dynamics Computer Simulations

    NASA Astrophysics Data System (ADS)

    Rosencrance, Scott William

    1995-01-01

    Simultaneous collection of energy and angle resolved neutral (EARN) distributions resulting from keV ion bombardment of various materials is performed using a novel position sensitive detection scheme in tandem with multiphoton laser ionization of desorbed neutral species. This enables experimental investigation of desorption processes at the atomic level. Insight into long-standing mechanistic uncertainties surrounding ion/solid interactions is set forth. When these results are viewed collectively a coherent picture of the desorption event emerges. In the first study, experimentally obtained EARN distributions for ground state Ni and Rh atoms desorbed from the { 001} crystal face by 5 keV Ar^+ bombardment are compared with molecular dynamics (MD) simulations. These calculations utilize the molecular dynamics/Monte Carlo -corrected effective medium (MD/MC-CEM) interaction potential. The similarity of the mechanistically resolved quantities reinforces the view that inherent registry in the crystal lattice dictates microscopic events leading to the observed angular distributions of particles ejected subsequent to keV ion bombardment of solid surfaces. Additional evaluation of quantum state resolved energy distributions and populations of atoms desorbed from rm Ni{ 001} reveals that particles ejecting in the rm a^3F_{4,3,2} states have kinetic energy distributions which peak at 3 eV while particles ejecting in the rm a^3D_{3,2 } or rm a^1D_2 states have distributions which peak at 4.3 eV. Furthermore, the population in the ^3D_ {3,2} states is larger than the ground F state. These are the first results demonstrating that the band structure of the solid dictates desorption energetics and populations. Further investigation into desorption processes utilizes MD simulations that incorporate sample temperature. These calculations reproduce experimentally observed temperature dependence in ejection and suggests that the effect predominately results from surface quenching

  2. More is different: Reconciling eV sterile neutrinos with cosmological mass bounds

    NASA Astrophysics Data System (ADS)

    Tang, Yong

    2015-11-01

    It is generally expected that adding light sterile species would increase the effective number of neutrinos, Neff. In this paper we discuss a scenario that Neff can actually decrease due to the neutrino oscillation effect if sterile neutrinos have self-interactions. We specifically focus on the eV mass range, as suggested by the neutrino anomalies. With large self-interactions, sterile neutrinos are not fully thermalized in the early Universe because of the suppressed effective mixing angle or matter effect. As the Universe cools down, flavor equilibrium between active and sterile species can be reached after big bang nucleosynthesis (BBN) epoch, but leading to a decrease of Neff. In such a scenario, we also show that the conflict with cosmological mass bounds on the additional sterile neutrinos can be relaxed further when more light species are introduced. To be consistent with the latest Planck results, at least 3 sterile species are needed.

  3. Technical note: An improved estimate of uncertainty for source contribution from effective variance Chemical Mass Balance (EV-CMB) analysis

    NASA Astrophysics Data System (ADS)

    Shi, Guo-Liang; Zhou, Xiao-Yu; Feng, Yin-Chang; Tian, Ying-Ze; Liu, Gui-Rong; Zheng, Mei; Zhou, Yang; Zhang, Yuan-Hang

    2015-01-01

    The CMB (Chemical Mass Balance) 8.2 model released by the USEPA is a commonly used receptor model that can determine estimated source contributions and their uncertainties (called default uncertainty). In this study, we propose an improved CMB uncertainty for the modeled contributions (called EV-LS uncertainty) by adding the difference between the modeled and measured values for ambient species concentrations to the default CMB uncertainty, based on the effective variance least squares (EV-LS) solution. This correction reconciles the uncertainty estimates for EV and OLS regression. To verify the formula for the EV-LS CMB uncertainty, the same ambient datasets were analyzed using the equation we developed for EV-LS CMB uncertainty and a standard statistical package, SPSS 16.0. The same results were obtained by both ways indicate that the equation for EV-LS CMB uncertainty proposed here is acceptable. In addition, four ambient datasets were studies by CMB 8.2 and the source contributions as well as the associated uncertainties were obtained accordingly.

  4. Experimental search for hidden photon CDM in the eV mass range with a dish antenna

    SciTech Connect

    Suzuki, J.; Horie, T.; Inoue, Y.; Minowa, M.

    2015-09-15

    A search for hidden photon cold dark matter (HP CDM) using a new technique with a dish antenna is reported. From the result of the measurement, we found no evidence for the existence of HP CDM and set an upper limit on the photon-HP mixing parameter χ of ∼6×10{sup −12} for the hidden photon mass m{sub γ}=3.1±1.2 eV.

  5. Application of resonant laser postionization SNMS for quantitative depth profiling in stainless steel with oxide film

    NASA Astrophysics Data System (ADS)

    Kubota, N.; Hayashi, S.

    2008-12-01

    A resonance laser postionization secondary neutral mass spectroscopy (SNMS) system with a quadrupole mass spectrometer has been developed to investigate its fundamental process for quantitative analysis of metal alloys and compounds. The feature of our SNMS system is to bombard ions with low energy incidence. The energy dependence of Cr/Fe ratios and resonant enhanced multi-photon ionization spectra of Fe in three kinds of samples have been observed. These results indicate that the existence of oxygen may disturb the quantitative measurement due to the population change of a sputtered atom though oxygen irradiation could prevent selective sputtering and ion enhanced sub-surface redistribution in stainless steel. The measured depth profiles of Cr, Fe and Ni in the colored stainless steel have been in agreement with the reference values within a factor of about 2.

  6. Quantitative Surface Analysis of a Binary Drug Mixture—Suppression Effects in the Detection of Sputtered Ions and Post-Ionized Neutrals

    NASA Astrophysics Data System (ADS)

    Karras, Gabriel; Lockyer, Nicholas P.

    2014-05-01

    A systematic mass spectrometric study of two of the most common analgesic drugs, paracetamol and ibuprofen, is reported. The drugs were studied by means of secondary ion mass spectrometry (SIMS) and secondary neutral mass spectrometry (SNMS) using laser post-ionization (LPI) both in pure samples and in a two-component mixture. Ion suppression within the two-component system observed in SIMS mode is ameliorated using LPI under room temperature analysis. However, suppression effects are apparent in LPI mode on performing the analysis at cryogenic temperatures, which we attribute to changes in the desorption characteristics of sputtered molecules, which influences the subsequent post-ionization efficiency. This suggests different mechanisms of ion suppression in SIMS and LPI modes.

  7. Quantitative surface analysis of a binary drug mixture--suppression effects in the detection of sputtered ions and post-ionized neutrals.

    PubMed

    Karras, Gabriel; Lockyer, Nicholas P

    2014-05-01

    A systematic mass spectrometric study of two of the most common analgesic drugs, paracetamol and ibuprofen, is reported. The drugs were studied by means of secondary ion mass spectrometry (SIMS) and secondary neutral mass spectrometry (SNMS) using laser post-ionization (LPI) both in pure samples and in a two-component mixture. Ion suppression within the two-component system observed in SIMS mode is ameliorated using LPI under room temperature analysis. However, suppression effects are apparent in LPI mode on performing the analysis at cryogenic temperatures, which we attribute to changes in the desorption characteristics of sputtered molecules, which influences the subsequent post-ionization efficiency. This suggests different mechanisms of ion suppression in SIMS and LPI modes. PMID:24658806

  8. Sterile neutrinos with eV masses in cosmology — How disfavoured exactly?

    SciTech Connect

    Hamann, Jan; Hannestad, Steen; Raffelt, Georg G.; Wong, Yvonne Y.Y. E-mail: sth@phys.au.dk E-mail: yvonne.wong@physik.rwth-aachen.de

    2011-09-01

    We study cosmological models that contain sterile neutrinos with eV-range masses as suggested by reactor and short-baseline oscillation data. We confront these models with both precision cosmological data (probing the CMB decoupling epoch) and light-element abundances (probing the BBN epoch). In the minimal ΛCDM model, such sterile neutrinos are strongly disfavoured by current data because they contribute too much hot dark matter. However, if the cosmological framework is extended to include also additional relativistic degrees of freedom beyond the three standard neutrinos and the putative sterile neutrinos, then the hot dark matter constraint on the sterile states is considerably relaxed. A further improvement is achieved by allowing a dark energy equation of state parameter w < −1. While BBN strongly disfavours extra radiation beyond the assumed eV-mass sterile neutrino, this constraint can be circumvented by a small ν{sub e} degeneracy. Any model containing eV-mass sterile neutrinos implies also strong modifications of other cosmological parameters. Notably, the inferred cold dark matter density can shift up by 20–75% relative to the standard ΛCDM value.

  9. Analysis of solids with a secondary-neutral microprobe based on electron-gas post-ionization.

    PubMed

    Bieck, W; Gnaser, H; Oechsner, H

    1995-10-01

    The detection sensitivity and the lateral resolution in electron-gas SNMS have been improved in a newly developed secondary-neutral microprobe. This instrument combines the high post-ionization efficiency provided by the electron component of an rf-plasma (post-ionization probability alpha(0) of some 10(-2)) with a high-transmission magnetic mass spectrometer. Using the plasma as an effective primary ion source, secondary-neutral intensities of up to 10(9) cps can be realized for 1 keV Ar(+) ion bombardment and a primary current density of 1 mA/cm(2). To obtain laterally resolved secondary-neutral micrographs, a 20 keV-Ga(+)-ion beam produced in a liquid-metal ion source (LMIS) is utilized for sputter excitation. At Ga(+)-ion-beam currents of about 6 nA a spot size on the target of 1 microm is possible. The detection sensitivity in this operation mode is on the order of Mass spectra and laterally resolved images recorded with this microprobe instrument highlight its capacity as a surface analytical tool. PMID:15048491

  10. Analysis of Amphiphilic Lipids and Hydrophobic Proteins Using Nonresonant Femtosecond Laser Vaporization with Electrospray Post-Ionization

    NASA Astrophysics Data System (ADS)

    Brady, John J.; Judge, Elizabeth J.; Levis, Robert J.

    2011-04-01

    Amphiphilic lipids and hydrophobic proteins are vaporized at atmospheric pressure using nonresonant 70 femtosecond (fs) laser pulses followed by electrospray post-ionization prior to being transferred into a time-of-flight mass spectrometer for mass analysis. Measurements of molecules on metal and transparent dielectric surfaces indicate that vaporization occurs through a nonthermal mechanism. The molecules analyzed include the lipids 1-monooleoyl-rac-glycerol, 1,2-dihexanoyl- sn-glycero-3-phosphocholine, 1,2-dimyristoyl- sn-glycero-3-phosphocholine, and the hydrophobic proteins gramicidin A, B, and C. Vaporization of lipids from blood and milk are also presented to demonstrate that lipids in complex systems can be transferred intact into the gas phase for mass analysis.

  11. On the possibility of the determining the average mass composition near 10 to the 14th power eV through the solar magnetic field

    NASA Technical Reports Server (NTRS)

    Lloyd-Evans, J.

    1985-01-01

    The discovery of primary ultrahigh energy (UHE) gamma-rays has spawned plans for a new generation of air shower experiments with unprecedented directional resolution. Such accuracy permits observation of a cosmic ray shadow due to the solar disc. Particle trajectory simulations through models of the large scale solar magnetic field were performed. The shadow is apparent above 10 to the 15th power eV for all cosmic ray charges /Z/ 26; at lower energies, trajectories close to the Sun are bent sufficiently for this shadow to be lost. The onset of the shadow is rigidity dependent, and occurs at an energy per nucleus of approx. Z x 10 to the 13th power eV. The possibility of determining the average mass composition near 10 to the 14th power eV from 1 year's observation at a mountain altitude array is investigated.

  12. Spectrum and mass composition of cosmic rays in the energy range 1015-1018 eV derived from the Yakutsk array data

    NASA Astrophysics Data System (ADS)

    Knurenko, S. P.; Sabourov, A.

    2013-06-01

    A spectrum of cosmic rays within energy range 1015 - 3 × 1017 eV was derived from the data of the small Cherenkov setup, which is a part of the Yakutsk complex EAS array. In this, work a new series of observation is covered. These observations lasted from 2000 till 2010 and resulted in increased number of registered events within interval 1016-1018 eV, which in turn made it possible to reproduce cosmic ray spectrum in this energy domain with better precision. A sign of a thin structure is observed in the shape of the spectrum. It could be related to the escape of heavy nuclei from our Galaxy. Cosmic ray mass composition was obtained for the energy region 1016-1018 eV. A joint analysis of spectrum and mass composition of cosmic rays was performed. Obtained results are considered in the context of theoretical computations that were performed with the use of hypothesis of galactic and meta-galactic origin of cosmic rays.

  13. Efficient small sample analysis via laser post-ionized neutrals desorbed from surfaces: LPI-SNMS

    NASA Astrophysics Data System (ADS)

    Veryovkin, I.; Calaway, W.; Pellin, M.; Moore, J.; Burnett, D.

    2003-04-01

    A number of popular analytical techniques rely on ion sputtering or laser desorption to probe solid samples. The popularity of this class of techniques is derived from the fact that they produce information on elemental and molecular compositions at trace levels. These techniques are particularly amenable to small sample analysis, since both ion and photon beams can be focused to sub-micron dimensions. Because ion sputtering and laser desorption consume material, there exists a trade off between sample size and achievable detection limit. This trade off is quantified by an instruments useful yield, which is defined as the number of atoms detected per atoms consumed. Laser post-ionization secondary neutral mass spectrometry (LPI-SNMS) has useful yields significantly higher than competing techniques and is thus well suited for trace analysis of small samples. With LPI-SNMS, either a pulse of energetic ions or photons remove material from a solid surface into the gas phase. The desorbed material, predominantly ground state neutral atoms, is photo-ionized by one or more lasers and then extracted into a mass spectrometer for detection. At Argonne National Laboratory, we have developed a new reflectron time-of flight (TOF) mass spectrometer especially designed to optimize useful yield in LPI-SNMS measurements. Using ion optics simulations, an improved extraction design has been developed that allows photo ions from a large (4 × 4 × 3 mm^3) volume above a sample surface to be transmitted through a TOF mass spectrometer with > 98% efficiency. Efficient extraction from such a large ionization volume means that more than 40% of all desorbed species are available for detection, producing an overall useful yield of > 30%. Such a high sensitivity allows analysis of small samples at trace levels never before achievable, opening many new applications. For example, the new LPI-SNMS instrument will allow (1) part-per-trillion detections of solar wind elements implanted in the top

  14. Applicability of post-ionization theory to laser-assisted field evaporation of magnetite

    SciTech Connect

    Schreiber, Daniel K.; Chiaramonti, Ann N.; Gordon, Lyle M.; Kruska, Karen

    2014-12-15

    Analysis of the mean Fe ion charge state from laser-assisted field evaporation of magnetite (Fe3O4) reveals unexpected trends as a function of laser pulse energy that break from conventional post-ionization theory for metals. For Fe ions evaporated from magnetite, the effects of post-ionization are partially offset by the increased prevalence of direct evaporation into higher charge states with increasing laser pulse energy. Therefore the final charge state is related to both the field strength and the laser pulse energy, despite those variables themselves being intertwined when analyzing at a constant detection rate. Comparison of data collected at different base temperatures also show that the increased prevalence of Fe2+ at higher laser energies is possibly not a direct thermal effect. Conversely, the ratio of 16O+:16O2+ is well-correlated with field strength and unaffected by laser pulse energy on its own, making it a better overall indicator of the field evaporation conditions than the mean Fe charge state. Plotting the normalized field strength versus laser pulse energy also elucidates a non-linear dependence, in agreement with previous observations on semiconductors, that suggests a field-dependent laser absorption efficiency. Together these observations demonstrate that the field evaporation process for laser-pulsed oxides exhibits fundamental differences from metallic specimens that cannot be completely explained by post-ionization theory. Further theoretical studies, combined with detailed analytical observations, are required to understand fully the field evaporation process of non-metallic samples.

  15. Imaging with Mass Spectrometry: A SIMS and VUV-Photoionization Study of Ion-Sputtered Atoms and Clusters from GaAs and Au

    SciTech Connect

    Takahashi, Lynelle; Zhou, Jia; Wilson, Kevin R.; Leone, Stephen R.; Ahmed, Musahid

    2008-12-05

    A new mass spectrometry surface imaging method is presented in which ion-sputtered neutrals are postionized by wavelength-tunable vacuum ultraviolet (VUV) light from a synchrotron source. Mass spectra and signal counts of the photoionized neutrals from GaAs (100) and Au are compared to those of the secondary ions. While clusters larger than dimers are more efficiently detected as secondary ions, certain species, such as As2, Au and Au2, are more efficiently detected through the neutral channel. Continuously tuning the photon wavelength allows photoionization efficiency (PIE) curves to be obtained for sputtered Asm (m=1,2) and Aun (n=1-4). From the observed ionization thresholds, sputtered neutral As and Au show no clear evidence of electronic excitation, while neutral clusters have photoionization onsets shifted to lower energies by ~;;0.3 eV. These shifts are attributed to unresolved vibrational and rotational excitations. High-spatial resolution chemical imaging with synchrotron VUV postionization is demonstrated at two different photon energies using a copper TEM grid embedded in indium. The resulting images are used to illustrate the use of tunable VUV light for verifying mass peak assignments by exploiting the unique wavelength-dependent PIE of each sputtered neutral species. This capability is valuable for identifying compounds when imaging chemically complex systems with mass spectrometry-based techniques.

  16. Detection of photon bursts from single 200 eV Mg ions: Progress in photon burst mass spectrometry

    SciTech Connect

    Fairbank, W.M. Jr.; LaBelle, R.D.; Keller, R.A.; Chamberlin, E.P.

    1989-01-01

    Modern atom counting methods, based on advances in laser and accelerator technology, provide a valuable complement to traditional decay counting methods for radioisotope dating and tracer work. Tandem Accelerator Mass Spectrometry (TAMS) has already had a large impact on /sup 14/C dating and is beginning to provide new opportunities with /sup 10/Be and several other isotopes. We report here on progress in the development of a laser-based technique, Photon Burst Mass Spectrometry, which is potentially capable of analyzing many of the elements which are forbidden in TAMS because they do not form negative ions. We are especially interested in the noble gases, which have a variety of potential scientific and environmental applications.

  17. Upper Bound of 0.28 eV on Neutrino Masses from the Largest Photometric Redshift Survey

    SciTech Connect

    Thomas, Shaun A.; Abdalla, Filipe B.; Lahav, Ofer

    2010-07-16

    We present a new limit of (95% CL) on the sum of the neutrino masses assuming a flat {Lambda}CDM cosmology. This relaxes slightly to and when quasinonlinear scales are removed and w{ne}-1, respectively. These are derived from a new photometric catalogue of over 700 000 luminous red galaxies (MegaZ DR7) with a volume of 3.3 (Gpc h{sup -1}){sup 3} and redshift range 0.45

  18. A new broadly tunable (7.4-10.2 eV) laser based VUV light source and its first application to aerosol mass spectrometry

    NASA Astrophysics Data System (ADS)

    Hanna, S. J.; Campuzano-Jost, P.; Simpson, E. A.; Robb, D. B.; Burak, I.; Blades, M. W.; Hepburn, J. W.; Bertram, A. K.

    2009-01-01

    A laser based vacuum ultraviolet (VUV) light source using resonance enhanced four wave difference mixing in xenon gas was developed for near threshold ionization of organics in atmospheric aerosol particles. The source delivers high intensity pulses of VUV light (in the range of 1010 to 1013 photons/pulse depending on wavelength, 5 ns FWHM) with a continuously tunable wavelength from 122 nm (10.2 eV) to 168 nm (7.4 eV)E The setup allows for tight (<1 mm2) and precise focusing ([mu]rad pointing angle adjustability), attributes required for single particle detection. The generated VUV is separated from the pump wavelengths by a custom monochromator which ensures high spectral purity and minimizes absorptive losses. The performance of the source was characterized using organic molecules in the gas phase and optimal working conditions are reported. In the gas phase measurements, photoionization efficiency (PIE) curves were collected for seven different organic species with ionization energies spanning the full wavelength range of the VUV source. The measured appearance energies are very close to the literature values of the ionization energies for all seven species. The effectiveness of the source for single particle studies was demonstrated by analysis of individual caffeine aerosols vaporized by a pulsed CO2 laser in an ion trap mass spectrometer. Mass spectra from single particles down to 300 nm in diameter were collected. Excellent signal to noise characteristics for these small particles give a caffeine detection limit of 8 × 105 molecules which is equivalent to a single 75 nm aerosol, or approximately 1.5% of a 300 nm particleE The appearance energy of caffeine originating from the aerosol was also measured and found to be 7.91 ± 0.05 eV, in good agreement with literature values.

  19. Upper bound of 0.28 eV on neutrino masses from the largest photometric redshift survey.

    PubMed

    Thomas, Shaun A; Abdalla, Filipe B; Lahav, Ofer

    2010-07-16

    We present a new limit of ∑m(v) ≤ 0.28 (95% CL) on the sum of the neutrino masses assuming a flat ΛCDM cosmology. This relaxes slightly to ∑m(ν) ≤ 0.34 and ∑m(v) ≤ 0.47 when quasinonlinear scales are removed and w≠ -1, respectively. These are derived from a new photometric catalogue of over 700,000 luminous red galaxies (MegaZ DR7) with a volume of 3.3  (Gpc h(-1))(3) and redshift range 0.45 < z < 0.65. The data are combined with WMAP 5-year CMB, baryon acoustic oscillations, supernovae, and a Hubble Space Telescope prior on h. When combined with WMAP these data are as constraining as adding all supernovae and baryon oscillation data available. The upper limit is one of the tightest constraints on the neutrino from cosmology or particle physics. Further, if these bounds hold, they all predict that current-to-next generation neutrino experiments, such as KATRIN, are unlikely to obtain a detection. PMID:20867754

  20. Role of oxygen in the angular distribution of sputtered constituents from Fe/Cr alloy studied by laser post-ionization SNMS

    NASA Astrophysics Data System (ADS)

    Im, Hoong-Sun; Ichimura, S.

    1997-02-01

    Laser post-ionization sputtered neutral mass spectrometry (SNMS) has been applied to study the angular distribution of the sputtered constituents of Fe-40at%Cr alloys. Preferred Cr ejection was observed in the direction of the target normal under sputtering in atmosphere with a sufficient amount of oxygen gas, while there is no distinct difference in the angular dependence of the ratio of ejected components without oxygen. Comparing the results obtained by this method with those by the thin film deposition method, it is certified that the same results can be attained by both methods, although in-situ measurement of the angular distribution of the sputtered constituents is possible only by the laser SNMS method. This tendency is considered to be due to the formation of Fe segregated layeres on the surface of the alloy by the presence of oxygen.

  1. Mass composition of cosmic rays with energies E 0 ≥ 1017 eV according to the data from the ground-based detectors of the Yakutsk EAS array

    NASA Astrophysics Data System (ADS)

    Glushkov, A. V.; Saburov, A. V.

    2015-02-01

    The lateral distribution of charged particles measured by ground-based scintillation detectors in extensive air showers (EASs) with the energy E 0 ≥ 1017 eV at the Yakutsk EAS array in 1977-2013 has been analyzed. The experimental data have been compared to the calculations within various models of the development of EASs from the CORSIKA package. The experimental data are in the best agreement with the QGSJET-01-d and QGSJET II-04 models. The mass composition of cosmic rays in the energy range (1-20) × 1017 eV changes from to a purely proton composition.

  2. Postionization fragmentation of rare-gas trimers revisited with new theoretical approaches

    NASA Astrophysics Data System (ADS)

    Janeček, Ivan; Cintavá, Silvie; Hrivňák, Daniel; Kalus, René; Fárník, Michal; Gadea, Florent Xavier

    2009-09-01

    A new theoretical approach is presented for the general treatment of nonadiabatic hybrid dynamics (mixing classical and quantum approach) and applied to the postionization of rare-gas trimers. There was an important disagreement between trajectory surface hopping (TSH) or mean field (MF) approaches and the experimental results; noteworthy, with the new method qualitative and almost quantitative agreement is found for the fragmentation ratios of ionic monomers and dimers. For the first time in the theory as in the experiment, the dimers prevail for argon while monomers strongly dominate for the heavier rare gases, krypton and xenon. A new compromise between MF and TSH approaches is proposed and the new method is found quite robust with results not too sensitive to various possible implementations.

  3. New limits on spin-independent and spin-dependent couplings of low-mass WIMP dark matter with a germanium detector at a threshold of 220 eV

    SciTech Connect

    Lin, S. T.; Li, H. B.; Lin, S. K.; Wong, H. T.; Lin, C. W.; Lin, F. K.; Wang, J. J.; Wang, Y. R.; Wu, S. C.; Li, X.; Fang, B. B.; He, D.; Yue, Q.; Deniz, M.; Li, J.; Ruan, X. C.; Zhou, Z. Y.; Singh, V.; Soma, A. K.

    2009-03-15

    An energy threshold of (220{+-}10) eV was achieved at an efficiency of 50% with a four-channel ultralow-energy germanium detector, each with an active mass of 5 g. This provides a unique probe to weakly interacting massive particles (WIMP) dark matter with mass below 10 GeV. With a data acquisition live time of 0.338 kg-day at the Kuo-Sheng Laboratory, constraints on WIMPs in the galactic halo were derived. The limits improve over previous results on both spin-independent WIMP-nucleon and spin-dependent WIMP-neutron cross-sections for WIMP mass between 3 and 6 GeV. Sensitivities for full-scale experiments are projected. This detector technique makes the unexplored sub-keV energy window accessible for new neutrino and dark matter experiments.

  4. Mass composition of 10{sup 17}- to 10{sup 18}-eV primary cosmic rays according to data on the lateral distribution of radio emission from extensive air showers

    SciTech Connect

    Kalmykov, N. N. Konstantinov, A. A.; Vedeneev, O. V.

    2012-12-15

    Experimental data obtained for the lateral distribution of radio emission from extensive air showers (EAS) at the array of Moscow State University (30-34 MHz) and the LOPES array (40-80 MHz) were comparedwith the results of calculations performed within amicroscopic approach based on aMonte Carlo simulation of EAS (CORSIKA code). The same experimental data were used to reconstruct the distribution of the depth of the EAS maximum at cosmic-ray energies in the range of 1017-1018 eV. The energy dependence of the depth of the EAS maximum was constructed for the case of data from the LOPES array, and the mass composition of cosmic rays was estimated for this case. From the resulting dependences, it follows that the mass composition shows a trend toward becoming lighter in the energy range being considered.

  5. Proteomics analysis of EV71-infected cells reveals the involvement of host protein NEDD4L in EV71 replication.

    PubMed

    Kuo, Rei-Lin; Lin, Ya-Han; Wang, Robert Yung-Liang; Hsu, Chia-Wei; Chiu, Yi-Ting; Huang, Hsing-I; Kao, Li-Ting; Yu, Jau-Song; Shih, Shin-Ru; Wu, Chih-Ching

    2015-04-01

    Enterovirus 71 (EV71) is a human enterovirus that has seriously affected the Asia-Pacific area for the past two decades. EV71 infection can result in mild hand-foot-and-mouth disease and herpangina and may occasionally lead to severe neurological complications in children. However, the specific biological processes that become altered during EV71 infection remain unclear. To further explore host responses upon EV71 infection, we identified proteins differentially expressed in EV71-infected human glioblastoma SF268 cells using isobaric mass tag (iTRAQ) labeling coupled with multidimensional liquid chromatography-mass spectrometry (LC-MS/MS). Network analysis of proteins altered in cells infected with EV71 revealed that the changed biological processes are related to protein and ion transport, regulation of protein degradation, and homeostatic processes. We confirmed that the levels of NEDD4L and PSMF1 were increased and reduced, respectively, in EV71-infected cells compared to mock-infected control cells. To determine the physiological relevance of our findings, we investigated the consequences of EV71 infection in cells with NEDD4L or PSMF1 depletion. We found that the depletion of NEDD4L significantly reduced the replication of EV71, whereas PSMF1 knockdown enhanced EV71 replication. Collectively, our findings provide the first evidence of proteome-wide dysregulation by EV71 infection and suggest a novel role for the host protein NEDD4L in the replication of this virus. PMID:25785312

  6. Did CDM particles of mass 2.47 x 10(-3) eV interact with precursor biopolymers and nucleic acids to initiate and boost lifeforms on Earth?

    PubMed

    Rosen, Gerald

    2011-06-01

    Recent observations and theoretical studies have shown that non-baryonic Cold Dark Matter (CDM), which constitutes about 84% of all matter in the Universe, may feature a complex-scalar-field that carries particles of mass ≅ 2.47 x 10(-3)eV with the associated Compton range m(-1) ≅8.02 x 10(-3) cm, a distance on the scale of extended bionucleic acids and living cells. Such a complex-scalar-field can enter a weak-isospin Lorentz-invariant interaction that generates the flow of right-handed electrons and induces a chirality-imbued quantum chemistry on the m (-1) scale. A phenomenological Volterra-type equation is proposed for the CDM-impacted time development of N, the number of base pairs in the most advanced organism at Earth-age t. The solution to this equation suggests that the boosts in N at t ≅ 1.1 Gyr (advent of the first living prokaryotic cells), at t ≅ 2.9 Gyr (advent of eukaryotic single-celled organisms) and finally at t ≅ 4.0 Gyr (the Cambrian explosion) may be associated with three multi-Myr-duration cosmic showers of the complex-scalar-field CDM particles. If so, the signature of the particles may be detectible in Cambrian rocks. PMID:21057875

  7. Did CDM Particles of Mass 2.47 × 10-3 eV Interact with Precursor Biopolymers and Nucleic Acids to Initiate and Boost Lifeforms on Earth?

    NASA Astrophysics Data System (ADS)

    Rosen, Gerald

    2011-06-01

    Recent observations and theoretical studies have shown that non-baryonic Cold Dark Matter (CDM), which constitutes about 84% of all matter in the Universe, may feature a complex-scalar-field that carries particles of mass m ≅ 2.47 × {10^{{ - 3}}}eV with the associated Compton range {m^{{ - 1}}} ≅ 8.02 × {10^{{ - 3}}}cm, a distance on the scale of extended bionucleic acids and living cells. Such a complex-scalar-field can enter a weak-isospin Lorentz-invariant interaction that generates the flow of right-handed electrons and induces a chirality-imbued quantum chemistry on the m -1 scale. A phenomenological Volterra-type equation is proposed for the CDM-impacted time development of N, the number of base pairs in the most advanced organism at Earth-age t. The solution to this equation suggests that the boosts in N at t ≅ 1.1 Gyr (advent of the first living prokaryotic cells), at t ≅ 2.9 Gyr (advent of eukaryotic single-celled organisms) and finally at t ≅ 4.0 Gyr (the Cambrian explosion) may be associated with three multi-Myr-duration cosmic showers of the complex-scalar-field CDM particles. If so, the signature of the particles may be detectible in Cambrian rocks.

  8. Internal Energy Deposition for Low Energy, Femtosecond Laser Vaporization and Nanospray Post-ionization Mass Spectrometry using Thermometer Ions

    NASA Astrophysics Data System (ADS)

    Flanigan, Paul M.; Shi, Fengjian; Archer, Jieutonne J.; Levis, Robert J.

    2015-05-01

    The internal energy of p-substituted benzylpyridinium ions after laser vaporization using low energy, femtosecond duration laser pulses of wavelengths 800 and 1042 nm was determined using the survival yield method. Laser vaporization of dried benzylpyridinium ions from metal slides into a buffered nanospray with 75 μJ, 800 nm laser pulses resulted in a higher extent of fragmentation than conventional nanospray due to the presence of a two-photon resonance fragmentation pathway. Using higher energy 800 nm laser pulses (280 and 505 μJ) led to decreased survival yields for the four different dried benzylpyridinium ions. Analyzing dried thermometer ions with 46.5 μJ, 1042 nm pulse-bursts resulted in little fragmentation and mean internal energy distributions equivalent to nanospray, which is attributable to the absence of a two-photon resonance that occurs with higher energy, 800 nm laser pulses. Vaporization of thermometer ions from solution with either 800 nm or 1042 nm laser pulses resulted in comparable internal energy distributions to nanospray ionization.

  9. Internal energy deposition for low energy, femtosecond laser vaporization and nanospray post-ionization mass spectrometry using thermometer ions.

    PubMed

    Flanigan, Paul M; Shi, Fengjian; Archer, Jieutonne J; Levis, Robert J

    2015-05-01

    The internal energy of p-substituted benzylpyridinium ions after laser vaporization using low energy, femtosecond duration laser pulses of wavelengths 800 and 1042 nm was determined using the survival yield method. Laser vaporization of dried benzylpyridinium ions from metal slides into a buffered nanospray with 75 μJ, 800 nm laser pulses resulted in a higher extent of fragmentation than conventional nanospray due to the presence of a two-photon resonance fragmentation pathway. Using higher energy 800 nm laser pulses (280 and 505 μJ) led to decreased survival yields for the four different dried benzylpyridinium ions. Analyzing dried thermometer ions with 46.5 μJ, 1042 nm pulse-bursts resulted in little fragmentation and mean internal energy distributions equivalent to nanospray, which is attributable to the absence of a two-photon resonance that occurs with higher energy, 800 nm laser pulses. Vaporization of thermometer ions from solution with either 800 nm or 1042 nm laser pulses resulted in comparable internal energy distributions to nanospray ionization. PMID:25724375

  10. Development of EV71 virus-like particle purification processes.

    PubMed

    Lin, Shih-Yeh; Chiu, Hsin-Yi; Chiang, Bor-Luen; Hu, Yu-Chen

    2015-11-01

    Enterovirus 71 (EV71) causes the outbreaks of hand-foot-and-mouth disease and results in deaths of hundreds of young children. EV71 virus-like particles (VLPs) are empty capsids consisting of viral structural proteins and can elicit potent immune responses, thus holding promise as an EV71 vaccine candidate. However, an efficient, scalable production and purification scheme is missing. For mass production of EV71 VLPs, this study aimed to develop a production and chromatography-based purification process. We first demonstrated the successful EV71 VLPs production in the stirred-tank bioreactor in which High Five™ cells were infected with a recombinant baculovirus co-expressing EV71 structural polyprotein P1 and protease 3CD. The culture supernatant containing the VLPs was subjected to tangential flow filtration (TFF) for concentration/diafiltration, which enabled the removal of >80% of proteins while recovering >80% of VLPs. The concentrated VLPs were next subjected to hydroxyapatite chromatography (HAC) in which the VLPs were mainly found in the flow through. After another TFF concentration/diafiltration, the VLPs were purified by size-exclusion chromatography (SEC) and concentrated/diafiltered by a final TFF. The integrated process yielded an overall VLPs recovery of ≈ 36% and a purity of ≈ 83%, which was better or comparable to the recovery and purity for the purification of live EV71 virus particles. This process thus may move the EV71 VLPs vaccine one step closer to the clinical applications. PMID:25939279

  11. A mass spectrometric analysis of {gamma}-GPS films

    SciTech Connect

    Dillingham, R.G.; Boerio, F.J.; Bertelsen, C.; Savina, M.R.; Lykke, K.R.; Calaway, W.F.

    1996-06-01

    {gamma}-glycidoxypropyltrimethoxysilane ({gamma}-GPS) is used for pre-treatment of grit-blasted aluminum before adhesive bonding. This paper discusses analysis of non-reflective grit-blasted surfaces using mass spectrometry of species that were either sputtered off using an ion beam or thermally desorbed as neutrals using a pulsed laser and then post-ionized using a secondary laser. Results show that fragmentation is excessive and structural information is difficult to obtain from the spectra.

  12. How Do The EV Project Participants Feel About Their EVS?

    SciTech Connect

    Francfort, James E.

    2015-02-01

    The EV Project is an infrastructure study that enrolled over 8,000 residential participants. These participants purchased or leased a Nissan Leaf battery electric vehicle (BEV) or Chevrolet Volt extended range electric vehicle (EREV) and were among the first to explore this new electric drive technology. Collectively, BEV, EREV, and plug-in hybrid electric vehicles (PHEVs) are called plug-in electric vehicles (PEVs). The EV Project participants were very cooperative and enthusiastic about their participation in the project and very supportive in providing feedback and information. The information and attitudes of these participants concerning their experience with their PEVs were solicited using a survey in June 2013. At that time, some had up to 3 years of experience with their PEVs.

  13. Electrospray-assisted laser desorption/ionization mass spectrometry for direct ambient analysis of solids.

    PubMed

    Shiea, Jentaie; Huang, Min-Zon; Hsu, Hsiu-Jung; Lee, Chi-Yang; Yuan, Cheng-Hui; Beech, Iwona; Sunner, Jan

    2005-01-01

    A new method of electrospray-assisted laser desorption/ionization (ELDI) mass spectrometry, which combines laser desorption with post-ionization by electrospray, was applied to rapid analysis of solid materials under ambient conditions. Analytes were desorbed from solid metallic and insulating substrata using a pulsed nitrogen laser. Post-ionization produced high-quality mass spectra characteristic of electrospray, including protein multiple charging. For the first time, mass spectra of intact proteins were obtained using laser desorption without adding a matrix. Bovine cytochrome c and an illicit drug containing methaqualone were chosen in this study to demonstrate the applicability of ELDI to the analysis of proteins and synthetic organic compounds. PMID:16299699

  14. Overcoming the high cost of EV batteries

    SciTech Connect

    Wright, S.R.

    1995-07-01

    Electric Vehicles (EV`s) are a solution to three major problems facing the US today. The commercialization of EV`s will reduce the growing trade deficit, provide economic gains from a new electric automobile industry, and help alleviate the air pollution problems encountered in many of America`s largest cities. The existence of EV`s is not the answer; their increasing use is. This increase in deployment will largely depend on vehicle price and not range limitations as many would have you believe. The price of an EV will be determined by the auto makers with their economics determining the ultimate price to the consumer. The cost of EV batteries is considered to be a major hurdle in achieving an affordable EV. Prices of EV batteries at this time cannot be controlled by the auto manufacturers. How high is this cost hurdle and what measures can be taken to reduce this obstacle and facilitate the successful commercialization of EV`s? This paper discusses a variety of alternatives. Each sector of industry may favor a particular solution, but, in order for the EV industry to thrive, all sectors must agree to work together to provide for customer needs.

  15. EV space suit gloves (passive)

    NASA Technical Reports Server (NTRS)

    Fletcher, E. G.; Dodson, J. D.; Elkins, W.; Tickner, E. G.

    1975-01-01

    A pair of pressure and thermal insulating overgloves to be used with an Extravehicular (EV) suit assembly was designed, developed, fabricated, and tested. The design features extensive use of Nomex felt materials in lieu of the multiple layer insulation formerly used with the Apollo thermal glove. The glove theoretically satisfies all of the thermal requirements. The presence of the thermal glove does not degrade pressure glove tactility by more than the acceptable 10% value. On the other hand, the thermal glove generally degrades pressure glove mobility by more than the acceptable 10% value, primarily in the area of the fingers. Life cycling tests were completed with minimal problems. The thermal glove/pressure glove ensemble was also tested for comfort; the test subjects found no problems with the thermal glove although they did report difficulties with pressure points on the pressure glove which were independent of the thermal glove.

  16. Serological detection and analysis of anti-VP1 responses against various enteroviruses (EV) (EV-A, EV-B and EV-C) in Chinese individuals.

    PubMed

    Gao, Caixia; Ding, Yingying; Zhou, Peng; Feng, Jiaojiao; Qian, Baohua; Lin, Ziyu; Wang, Lili; Wang, Jinhong; Zhao, Chunyan; Li, Xiangyu; Cao, Mingmei; Peng, Heng; Rui, Bing; Pan, Wei

    2016-01-01

    The overall serological prevalence of EV infections based on ELISA remains unknown. In the present study, the antibody responses against VP1 of the EV-A species (enterovirus 71 (EV71), Coxsackievirus A16 (CA16), Coxsackievirus A5 (CA5) and Coxsackievirus A6 (CA6)), of the EV-B species (Coxsackievirus B3 (CB3)), and of the EV-C species (Poliovirus 1 (PV1)) were detected and analyzed by a NEIBM (novel evolved immunoglobulin-binding molecule)-based ELISA in Shanghai blood donors. The serological prevalence of anti-CB3 VP1 antibodies was demonstrated to show the highest level, with anti-PV1 VP1 antibodies at the second highest level, and anti-CA5, CA6, CA16 and EV71 VP1 antibodies at a comparatively low level. All reactions were significantly correlated at different levels, which were approximately proportional to their sequence similarities. Antibody responses against EV71 VP1 showed obvious differences with responses against other EV-A viruses. Obvious differences in antibody responses between August 2013 and May 2014 were revealed. These findings are the first to describe the detailed information of the serological prevalence of human antibody responses against the VP1 of EV-A, B and C viruses, and could be helpful for understanding of the ubiquity of EV infections and for identifying an effective approach for seroepidemiological surveillance based on ELISA. PMID:26917423

  17. Serological detection and analysis of anti-VP1 responses against various enteroviruses (EV) (EV-A, EV-B and EV-C) in Chinese individuals

    PubMed Central

    Gao, Caixia; Ding, Yingying; Zhou, Peng; Feng, Jiaojiao; Qian, Baohua; Lin, Ziyu; Wang, Lili; Wang, Jinhong; Zhao, Chunyan; Li, Xiangyu; Cao, Mingmei; Peng, Heng; Rui, Bing; Pan, Wei

    2016-01-01

    The overall serological prevalence of EV infections based on ELISA remains unknown. In the present study, the antibody responses against VP1 of the EV-A species (enterovirus 71 (EV71), Coxsackievirus A16 (CA16), Coxsackievirus A5 (CA5) and Coxsackievirus A6 (CA6)), of the EV-B species (Coxsackievirus B3 (CB3)), and of the EV-C species (Poliovirus 1 (PV1)) were detected and analyzed by a NEIBM (novel evolved immunoglobulin-binding molecule)-based ELISA in Shanghai blood donors. The serological prevalence of anti-CB3 VP1 antibodies was demonstrated to show the highest level, with anti-PV1 VP1 antibodies at the second highest level, and anti-CA5, CA6, CA16 and EV71 VP1 antibodies at a comparatively low level. All reactions were significantly correlated at different levels, which were approximately proportional to their sequence similarities. Antibody responses against EV71 VP1 showed obvious differences with responses against other EV-A viruses. Obvious differences in antibody responses between August 2013 and May 2014 were revealed. These findings are the first to describe the detailed information of the serological prevalence of human antibody responses against the VP1 of EV-A, B and C viruses, and could be helpful for understanding of the ubiquity of EV infections and for identifying an effective approach for seroepidemiological surveillance based on ELISA. PMID:26917423

  18. Mass

    SciTech Connect

    Chris Quigg

    2007-12-05

    In the classical physics we inherited from Isaac Newton, mass does not arise, it simply is. The mass of a classical object is the sum of the masses of its parts. Albert Einstein showed that the mass of a body is a measure of its energy content, inviting us to consider the origins of mass. The protons we accelerate at Fermilab are prime examples of Einsteinian matter: nearly all of their mass arises from stored energy. Missing mass led to the discovery of the noble gases, and a new form of missing mass leads us to the notion of dark matter. Starting with a brief guided tour of the meanings of mass, the colloquium will explore the multiple origins of mass. We will see how far we have come toward understanding mass, and survey the issues that guide our research today.

  19. Mass spectrometry on the nanoscale with ion sputtering based techniques: What is feasible

    NASA Astrophysics Data System (ADS)

    Veryovkin, Igor V.; Calaway, Wallis F.; Tripa, C. Emil; Pellin, Michael J.

    2007-08-01

    The potential of ion sputtering based mass spectrometry applied to materials characterization on the nanometer scale is discussed. Analytical approaches and required instrumental capabilities are outlined, and the current state-of-the-art is summarized. A new generation of analytical instruments specifically optimized for laser post-ionization secondary neutral mass spectrometry has been developed at Argonne National Laboratory (ANL). Experimentally verified (or anticipated after near-future upgrades) analytical capabilities of these instruments, capable of quantitative analysis at the nanometer-scale, are reported and compared to secondary ion mass spectrometry.

  20. The cosmic ray spectrum and composition measured by KASCADE-Grande between 1016 eV and 1018 eV

    NASA Astrophysics Data System (ADS)

    Bertaina, M.; Apel, W. D.; Arteaga-Velázquez, J. C.; Bekk, K.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Engler, J.; Fuchs, B.; Fuhrmann, D.; Gherghel-Lascu, A.; Gils, H. J.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Huber, D.; Huege, T.; Kampert, K.-H.; Kang, D.; Klages, H. O.; Link, K.; Łuczak, P.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.; Oehlschläger, J.; Ostapchenko, S.; Palmieri, N.; Petcu, M.; Pierog, T.; Rebel, H.; Roth, M.; Schieler, H.; Schoo, S.; Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Ulrich, H.; Weindl, A.; Wochele, J.; Zabierowski, J.

    2014-11-01

    The shape and composition of the primary spectrum of cosmic rays are key elements to understand the origin, acceleration and propagation of the Galactic cosmic rays. Besides the well known knee and ankle features, the recent results of KASCADE-Grande indicate that the measured energy spectrum exhibits also a less pronounced but still clear deviation from a single power law between the knee and the ankle, with a spectral hardening at 2 × 1016 eV and a steepening at 1017 eV. The average mass composition gets heavier after the knee till 1017 eV where a bending of the heavy component is observed. An indication of a hardening of the light component just above 1017 eV has been measured as well. In this paper the major results obtained so far by the KASCADE-Grande experiment are reviewed.

  1. Energy impacts in producing and recycling EV batteries

    SciTech Connect

    1996-02-01

    This article reports that choosing the best EV battery involves more than a quest for greater range per charge, as total energy cycle assessment of batteries demonstrates. Much has been written about the performance characteristics of electric vehicle (EV) batteries, but information about materials and the production and recycling processes is not as readily available. Such information has not been the primary focus of interest, since designs and processes are still under development, and much of the information is proprietary. An overview of four electric vehicle batteries--advanced lead/acid, sodium/sulfur, nickel/cadmium and nickel/metal hydride--highlights significant differences in energy consumption during production and recycling of materials used in the batteries. Certain realities apply to these batteries, despite their technical distinctions. First, and most obvious, the batteries will make up a significant fraction, 20--40%, of vehicle mass. Impacts are increased because some batteries with lifetimes shorter than the vehicle`s will need replacement at least once. Another insight is that battery recyclability is being considered at the design stage because the electric vehicle is being born green, that is, environmentally benign from the onset. In contrast to the small consumer cells now simply being shredded, EV batteries will be large enough to warrant disassembly and material segregation as the first step in recycling. Electrode and electrolyte materials in advanced batteries are nonstandard in the automotive industry, so process information is not readily available.

  2. Laser ablation-miniature mass spectrometer for elemental and isotopic analysis of rocks.

    PubMed

    Sinha, M P; Neidholdt, E L; Hurowitz, J; Sturhahn, W; Beard, B; Hecht, M H

    2011-09-01

    A laser ablation-miniature mass spectrometer (LA-MMS) for the chemical and isotopic measurement of rocks and minerals is described. In the LA-MMS method, neutral atoms ablated by a pulsed laser are led into an electron impact ionization source, where they are ionized by a 70 eV electron beam. This results in a secondary ion pulse typically 10-100 μs wide, compared to the original 5-10 ns laser pulse duration. Ions of different masses are then spatially dispersed along the focal plane of the magnetic sector of the miniature mass spectrometer (MMS) and measured in parallel by a modified CCD array detector capable of detecting ions directly. Compared to conventional scanning techniques, simultaneous measurement of the ion pulse along the focal plane effectively offers a 100% duty cycle over a wide mass range. LA-MMS offers a more quantitative assessment of elemental composition than techniques that detect ions directly generated by the ablation process because the latter can be strongly influenced by matrix effects that vary with the structure and geometry of the surface, the wavelength of the laser beam, and the not well characterized ionization efficiencies of the elements in the process. The above problems attendant to the direct ion analysis has been minimized in the LA-MMS by analyzing the ablated neutral species after their post-ionization by electron impaction. These neutral species are much more abundant than the directly ablated ions in the ablated vapor plume and are, therefore, expected to be characteristic of the chemical composition of the solid. Also, the electron impact ionization of elements is well studied and their ionization cross sections are known and easy to find in databases. Currently, the LA-MMS limit of detection is 0.4 wt.%. Here we describe LA-MMS elemental composition measurements of various minerals including microcline, lepidolite, anorthoclase, and USGS BCR-2G samples. The measurements of high precision isotopic ratios including (41)K

  3. How much are Chevrolet Volts in The EV Project driven in EV Mode?

    SciTech Connect

    John Smart

    2013-08-01

    This report summarizes key conclusions from analysis of data collected from Chevrolet Volts participating in The EV Project. Topics include how many miles are driven in EV mode, how far vehicles are driven between charging events, and how much energy is charged from the electric grid per charging event.

  4. Cosmology based on f(R) gravity admits 1 eV sterile neutrinos.

    PubMed

    Motohashi, Hayato; Starobinsky, Alexei A; Yokoyama, Jun'ichi

    2013-03-22

    It is shown that the tension between recent neutrino oscillation experiments, favoring sterile neutrinos with masses of the order of 1 eV, and cosmological data which impose stringent constraints on neutrino masses from the free streaming suppression of density fluctuations, can be resolved in models of the present accelerated expansion of the Universe based on f(R) gravity. PMID:25166788

  5. EV71 vaccine, an invaluable gift for children

    PubMed Central

    Liang, Zhenglun; Wang, Junzhi

    2014-01-01

    Enterovirus 71 (EV71) is a major pathogen for severe hand, foot and mouth disease (HFMD). Development of vaccines against EV71 would be the most effective approach to prevent the EV71 outbreak. Research and development (R&D) of EV71 vaccine was carried out in several Asian countries. Currently three companies in mainland China have completed Phase III clinical trials of inactivated EV71 whole-virus vaccines, whereas the other two companies have completed Phase I clinical trials separately in Taiwan and in Singapore. Results from those clinical trials have indicated high safety and immunogenicity of EV71 vaccine. Protective efficacies were over 90% on EV71-associated HFMD and over 80% on other EV71-associated diseases. In this paper, we summarize the results from three EV71 vaccine Phase III clinical trials and discuss the challenges of incorporating EV71 vaccine into Expanded Program on Immunization (EPI) in countries with EV71 epidemics. PMID:25505956

  6. In memory of E.V. Shcherbinin

    NASA Astrophysics Data System (ADS)

    Editorial Board

    2004-09-01

    On August 3, 2004 died Eduard Vasilyevich Shcherbinin, an outstanding scientist, well known in the MHD world scientific community, Dr. hab. Phys., professor, the head of the Laboratory of Electrical Vortex Flows at the Institute of Physics of the University of Latvia, a member of the Advising Editorial Board of the Journal "MagnetoHydroDynamics". Just after graduation from the Leningrad Politechnical Institute (physics and mathematics faculty) in 1961, E.V. Shcherbinin joined the Institute of Physics and stayed there till his last days. He started his work as an engineer at the Institute of Physics, in 1966 he was awarded his first scientific degree of Candidate of Science, in 1977 he was awarded another scientific degree of Dr.Phys., in 1980 he became a professor of mathematics. Eduard Vasilyevich Shcherbinin has been awarded many prizes, among which are the prizes of the Presidium of the Latvian Academy of Sciences (1973, 1977, 1986) and the F.Tsander prize (1991). All his fruitful scientific activity was devoted to theoretical MHD fundamental problems and to practical application problems. E.V. Shcherbinin was the founder of a new branch in MHD - the so-called electrovortex flows, having direct relation to the optimization of many practical metallurgy processes such as aluminum reduction cells, induction channel furnaces, electric arc furnaces and electroslag re-melting of metals. E.V. Shcherbinin published 6 monographs, about 200 scientific papers, he has more than 40 patents. Alongside, E.V. Shcherbinin guided the scientific work of many post-graduates and gave lectures in mathematics for students. Under his guidance, 13 post-graduates have successfully prepared their theses in MHD. E.V. Shcherbinin was also active in organizing many international seminars and conferences and participating in them. Recently, E.V. Shcherbinin, being the head of the Laboratory of Electrical Vortex Flows has published the monograph "Theory of self-similar boundary layer in

  7. Smart cards for EV billing. Final report

    SciTech Connect

    1998-05-01

    If electric vehicles are to gain widespread popularity, there will need to be public charging stations for refueling away from home. However, public charging raises some potentially complex issues regarding how individual EV owners will be billed for the electricity they use. It`s easy enough to meter the electricity used at a given battery charger, but the utility bill goes to the EV station merchant rather than the driver who consumed the electricity. So far this has not posed a problem, as many early charging sites have either been providing free electricity or billing only nominal flat fees. As the EV market grows, however, an effective point-of-sale (POS) billing mechanism will need to be established. In 1993, an investigation of POS billing systems for different types of non-home EV charging was conducted. Recently, the Cost Subcommittee of the Infrastructure Working Council`s (IWC) Load Management, Distribution, Power Quality Committee requested that an update be performed on the newest of these POS technologies--smart cards. The same size and shape as regular credit cards, smart cards use a microchip instead of a magnetic stripe to store information. The chip can hold significantly more information than a magnetic stripe, enabling greater security and flexible applications. Since 1993, there have been major advances in smart card technology, and smart card use has grown dramatically in both Europe and Asia. The US has been slower to embrace smart cards due to the entrenched infrastructure of traditional magnetic stripe credit cards. This paper reviews smart card technology and related POS transaction structures, and assesses the technical feasibility and economics of using these versatile cards for EV billing.

  8. NASA JSC EV2 Intern Spring 2016 - Jennie Chung

    NASA Technical Reports Server (NTRS)

    Chung, Jennie

    2016-01-01

    Exploration Mission 2 (EM-2) is a mission to resume the manned exploration of the Solar System. This mission is the first crewed mission of NASA’s Orion on the Space Launch System. The target for EM-2 is to perform a flyby of a captured asteroid in lunar orbit, which NASA plans to launch in 2023. As an intern working with EV-2 – Avionics Systems Division in Johnson Space Center, we are developing flight instrumentation systems for EM-2 (MISL & RFID). The Modular Integrated Stackable Layer (MISL) is a compact space-related computer system that is modular, scalable and reconfigurable. The RFID (radio frequency identification) sensors are used to take lower frequency (TC) type measurements and be able to stream data real-time to an RF (radio frequency) interrogator upon demand. Our job, in EV-2, is to certify, test, manufacture/assemble and deliver flight EM-2 DFI System (MISL & RFID). Our goal is to propose a development effort to design low-mass wire and wireless data acquisition and sensor solutions for EM-2 DFI (Development Flight Instrumentation). The team is tasked to provide the most effective use of 75 pounds to acquire DFI data and to collect sensor data for 100-200 high priority DFI channels (mass driven).

  9. How Do The EV Project Participants Feel about Charging Their EV at Home?

    SciTech Connect

    Francfort, James E.

    2015-02-01

    Key Observations from the Survey of the EV Project Participants; In June 2013, 72% of EV Project participants were very satisfied with their home charging experience; 21% of participants relied totally on home charging for all of their charging needs; Volt owners relied more on home charging than Leaf owners, who reported more use of away-from-home charging; 74% of participants reported that they plug in their plug-in electric vehicle (PEV) every time they park at home. Others plugged in as they determined necessary to support their driving needs; 40% of participants reported that they would not have or are unsure that in June 2013 whether they would have purchased an alternating current (AC) Level 2 electric vehicle supply equipment (EVSE) for home charging if it had not been provided by The EV Project; and 61% of participants reported that The EV Project incentive was very important or important in their decision to obtain a PEV.

  10. Secondary neutral mass spectrometry (SNMS)-recent methodical progress and applications to fundamental studies in particle/surface interaction

    NASA Astrophysics Data System (ADS)

    Oechsner, Hans

    1995-05-01

    Recent instrumental developments of the conventional secondary neutral mass spectrometry (SNMS) technique based on electron gas post-ionization are described with regard to its application to non-conducting samples and its implementation in a novel secondary neutral microprobe. The use of molecular SNMS signals for quantitative surface analysis, and a standard free technique for absolute depth calibration from the mass spectrometric signals are discussed and elucidated by appropriate examples. Finally, some applications of electron gas SNMS to fundamental studies on low energy particle/surface interaction are presented.

  11. BEST sensitivity to O(1) eV sterile neutrino

    NASA Astrophysics Data System (ADS)

    Barinov, Vladislav; Gavrin, Vladimir; Gorbunov, Dmitry; Ibragimova, Tatiana

    2016-04-01

    Numerous anomalous results in neutrino oscillation experiments can be attributed to the interference of an ˜1 eV sterile neutrino. The Baksan Experiment on Sterile Transitions (BEST), specially designed to fully explore the Gallium anomaly, starts next year. We investigate the sensitivity of BEST in search of a sterile neutrino mixed with an electron neutrino. Then, performing the combined analysis of all the Gallium experiments (SAGE, GALLEX, BEST), we find the region in the model parameter space (sterile neutrino mass and mixing angle) which will be excluded if BEST agrees with no sterile neutrino hypothesis. For the opposite case, if BEST observes the signal as it follows from the sterile neutrino explanation of the Gallium (SAGE and GALLEX) anomaly, we show how BEST will improve upon the present estimates of the model parameters.

  12. Enhanced Video Surveillance (EVS) with speckle imaging

    SciTech Connect

    Carrano, C J

    2004-01-13

    Enhanced Video Surveillance (EVS) with Speckle Imaging is a high-resolution imaging system that substantially improves resolution and contrast in images acquired over long distances. This technology will increase image resolution up to an order of magnitude or greater for video surveillance systems. The system's hardware components are all commercially available and consist of a telescope or large-aperture lens assembly, a high-performance digital camera, and a personal computer. The system's software, developed at LLNL, extends standard speckle-image-processing methods (used in the astronomical community) to solve the atmospheric blurring problem associated with imaging over medium to long distances (hundreds of meters to tens of kilometers) through horizontal or slant-path turbulence. This novel imaging technology will not only enhance national security but also will benefit law enforcement, security contractors, and any private or public entity that uses video surveillance to protect their assets.

  13. Simple cost model for EV traction motors

    NASA Astrophysics Data System (ADS)

    Cuenca, R. M.

    1995-02-01

    A simple cost model has been developed that allows the calculation of the OEM (original equipment manufacturer) cost of electric traction motors of three different types, normalized as a function of power in order to accommodate different power and size. The model includes enough information on the various elements integrated in the motors to allow analysis of individual components and to factor-in the effects of changes in commodities prices. A scalable cost model for each of the main components of an electric vehicle (EV) is a useful tool that can have direct application in computer simulation or in parametric studies. For the cost model to have wide usefulness, it needs to be valid for a range of values of some parameter that determines the magnitude or size of the component. For instance, in the case of batteries, size may be determined by energy capacity, usually expressed in kilowatt-hours (kWh), while in the case of traction motors, size is better determined by rated power, usually expressed in kilowatts (kW). The simplest case is when the cost of the component in question is a direct function of its size; then cost is simply the product of its specific cost ($/unit size) and the number of units (size) in the vehicle in question. Batteries usually fall in this category (cost = energy capacity x $/kWh). But cost is not always linear with size or magnitude; motors (and controllers), for instance, become relatively less expensive as power rating increases. Traction motors, one of the main components for EV powertrains, are examined in this paper, and a simplified cost model is developed for the three most popular design variations.

  14. Combined electron and focused ion beam system for improvement of secondary ion yield in secondary ion mass spectrometry instrument

    SciTech Connect

    Ji, L.; Ji, Q.; Leung, K.-N.; Gough, R. A.

    2006-10-16

    Using a combined electron and focused ion beam system to improve performance of secondary ion mass spectrometry instruments has been investigated experimentally. The secondary ion yield for an Al target has been enhanced to about one order of magnitude higher with the postionization induced by the low energy electrons in the combined beam. It can be further improved with the increase of electron beam current. When the combined beam is applied to insulating targets, sample charging is also eliminated. For Teflon targets, the secondary ion signal is increased by more than a factor of 20.

  15. Crew coordination issues of EVS approaches

    NASA Astrophysics Data System (ADS)

    Lorenz, Bernd; Korn, Bernd R.

    2004-08-01

    Enhanced Vision Systems (EVS) are currently developed with the goal to alleviate restrictions in airspace and airport capacity in low visibility conditions. Existing EVS-systems are based on IR-sensors although the penetration of bad weather (dense fog and light rain) by MMW-radar is remarkably better than in the infrared spectrum. But the quality of MMW radar is rather poor compared to IR images. However, the analysis of radar images can be simplified dramatically when simple passive radar retro-reflectors are used to mark the runway. This presentation is the third in a series of studies investigating the use of such simple landing aids. In the first study the feasibility of the radar PAPI concept was determined; the second one provided first promising human performance results in a low-fidelity simulation. The present study examined pilot performance, workload, situation awareness, and crew coordination issues in a high-fidelity simulation of 'Radar-PAPI' visual aids supporting a precision straight-in landing in low visibility (CAT-II). Simulation scenarios were completed in a fixed-base cockpit simulator involving six two-pilot flight-deck crews. Pilots could derive visual cues to correct lateral glide-path deviations from 13 pairs of runway-marking corner reflectors. Vertical deviations were indicated by a set of six diplane reflectors using intensity-coding to provide the PAPI categories needed for the correction of vertical deviations. The study compared three display formats and associated crew coordination issues: (1) PF views a head-down B-scope display and switches to visual landing upon PNF's call-out that runway is in sight; (2) PF views a head-down C-scope display and switches to visual landing upon PNF's call-out that runway is in sight; (3) PF views through a head-up display (HUD) that displays primary flight guidance information and receives vertical and lateral guidance from PNF who views a head-down B-scope. PNF guidance is terminated upon PF

  16. How Do The EV Project Participants Feel About Charging Their EV Away From Home?

    SciTech Connect

    Francfort, James E.

    2015-02-01

    The EV Project is an infrastructure study that enrolled over 8,000 residential participants. These participants purchased or leased a Nissan Leaf battery electric vehicle or Chevrolet Volt extended-range electric vehicle and were among the first to explore this new electric drive technology. Collectively, battery electric vehicles, extended-range electric vehicles, and plug-in hybrid electric vehicles are called PEVs. The EV Project participants were very cooperative and enthusiastic about their participation in the project and very supportive in providing feedback and information. The information and attitudes of these participants concerning their experience with their PEVs were solicited using a survey in June 2013. At that time, some had up to 3 years of experience with their PEVs.

  17. Possibilities and limitations of high-resolution mass spectrometry in life sciences

    NASA Astrophysics Data System (ADS)

    Arlinghaus, Heinrich F.

    2008-12-01

    We have applied time-of-flight secondary ion mass spectrometry (ToF-SIMS) and laser post-ionization secondary neutral mass spectrometry (laser-SNMS) to examine the immobilization process of PNA and its hybridization capability to unlabeled complementary DNA fragments, to characterize immobilized proteins, and to image intrinsic elements and molecules with subcellular spatial resolution in different types of frozen non-dehydrated biological samples. The possibilities and limitations of ToF-SIMS and laser-SNMS for imaging elements and molecules in biological samples are discussed. Furthermore possibilities for enhancing the detection sensitivity by using polyatomic and cluster primary ions and different laser post-ionization schemes, as well as ways of obtaining 3D molecular images from biological samples are described. The data shows that both ToF-SIMS and laser-SNMS are capable of imaging elements and molecules in complex biological samples and that they are very valuable tools in advancing applications in life sciences. It was found that cluster-ion bombardment is very useful for enhancing the molecular yield, while laser-SNMS resulted in much higher detection sensitivity for elements and specific molecules and is particularly well suited for imaging ultra-trace element concentrations in biological samples.

  18. The photofragmentation of naphthalene and azulene monocations in the energy range 7 22 eV

    NASA Astrophysics Data System (ADS)

    Jochims, H. W.; Rasekh, H.; Rühl, E.; Baumgärtel, H.; Leach, S.

    1992-12-01

    Photoion mass spectrometry was used to study the fragmentation of naphthalene and azulene monocations over the excitation energy range 7-22 eV. Fifteen fragmentation processes in naphthalene and twelve in azulene have been examined in detail. The photoionization mass spectra at 20.58 eV are quasi-identical for the two isomers. This, and the constant value of the difference between the fragment appearance energies (AE) for naphthalene and azulene, equal to the difference in the heats of formations of the neutral parents, suggest that identical products are formed. The unimolecular dissociations fall mainly into (i) a "low energy" group, (AE<16 eV) and (ii) a "high energy" group (AE > 18 eV). The reactions in (i) have in common the bicyclic precursor C 10H +8 ion 18 which decays via rupture of one ring. The group (ii) reactions involve rupture of both rings to give an open chain precursor, the 1,6-bis-ethinyl-hexatriene radical cation 20. Thermodynamic and mechanistic arguments are given to propose specific reaction pathways and product structures. Two general schemes rationalize the low-energy and high-energy ionic decompositions.

  19. VUV photophysics of acetic acid: Fragmentation, fluorescence and ionization in the 6 23 eV region

    NASA Astrophysics Data System (ADS)

    Leach, Sydney; Schwell, Martin; Jochims, Hans-Werner; Baumgärtel, Helmut

    2006-01-01

    VUV photodissociation of gaseous acetic acid was studied in the 6-23 eV range using synchrotron radiation excitation, photofragment fluorescence spectroscopy and mass spectrometry. OH (A-X), CH (A,B-X) and H-Balmer emissions were observed. Their relative intensities were studied by fluorescence excitation spectroscopy. The fluorescence quantum yield for OH emission has a maximum of 0.9% at 13.3 eV photoexcitation, dropping to 0.5% at 20 eV; that for CH (A-X) is 0.35% at 16 eV and 0.4% at 20 eV. Photoionization mass spectra (PIMS) of CH 3COOH were measured and the appearance energies of the principal photoions were determined. IE(CH 3COOH) = 10.58 ± 0.02 eV is 40-60 meV lower than previous PIMS values. Dissociative ionization reaction channels are discussed in detail. The results call into question previous determinations of the heat of formation and ionization energy of the acetyl radical. A new pathway is suggested for the formation of HCO +, and the assignments of the m/ z = 16, 28 and 31 ions are clarified. The formation of CH3+ at threshold is shown to involve carbon-carbon bond rupture and a potential energy barrier. The results of this study are used to discuss aspects of astrophysical observations involving the parent and fragment species.

  20. DOE Field Operations Program EV and HEV Testing

    SciTech Connect

    Francfort, James Edward; Slezak, L. A.

    2001-10-01

    The United States Department of Energy’s (DOE) Field Operations Program tests advanced technology vehicles (ATVs) and disseminates the testing results to provide fleet managers and other potential ATV users with accurate and unbiased information on vehicle performance. The ATVs (including electric, hybrid, and other alternative fuel vehicles) are tested using one or more methods - Baseline Performance Testing (EVAmerica and Pomona Loop), Accelerated Reliability Testing, and Fleet Testing. The Program (http://ev.inel.gov/sop) and its nine industry testing partners have tested over 30 full-size electric vehicle (EV) models and they have accumulated over 4 million miles of EV testing experience since 1994. In conjunction with several original equipment manufacturers, the Program has developed testing procedures for the new classes of hybrid, urban, and neighborhood EVs. The testing of these vehicles started during 2001. The EVS 18 presentation will include (1) EV and hybrid electric vehicle (HEV) test results, (2) operating experience with and performance trends of various EV and HEV models, and (3) experience with operating hydrogen-fueled vehicles. Data presented for EVs will include vehicle efficiency (km/kWh), average distance driven per charge, and range testing results. The HEV data will include operating considerations, fuel use rates, and range testing results.

  1. Multidimensional detection of explosives and explosive signatures via laser electrospray mass spectrometry

    NASA Astrophysics Data System (ADS)

    Brady, John J.; Flanigan, Paul M., IV; Perez, Johnny J.; Judge, Elizabeth J.; Levis, Robert J.

    2012-06-01

    Nitro- and inorganic-based energetic material is vaporized at atmospheric pressure using nonresonant, 70 femtosecond laser pulses prior to electrospray post-ionization and transfer into a time-of-flight mass spectrometer for mass analysis. Measurements of a nitro-based energetic molecule, cyclotrimethylenetrinitramine (RDX), adsorbed on metal and dielectric surfaces indicate nonresonant vaporization of intact molecules, demonstrating the universality of laser electrospray mass spectrometry (LEMS) technique for explosives. In addition, RDX is analyzed at a distance of 2 meters to demonstrate the remote detection capability of LEMS. Finally, the analysis and multivariate statistical classification of inorganic-based explosives containing ammonium nitrate, chlorate, perchlorate, black powder, and an organic-based explosive is presented, further expanding the capabilities of the LEMS technique for detection of energetic materials.

  2. Cosmic rays: the spectrum and chemical composition from 1010 to 1020 eV

    NASA Astrophysics Data System (ADS)

    Todero Peixoto, C. J.; de Souza, Vitor; Biermann, Peter L.

    2015-07-01

    The production of energetic particles in the universe remains one of the great mysteries of modern science. The mechanisms of acceleration in astrophysical sources and the details about the propagation through the galactic and extragalactic media are still to be defined. In recent years, the cosmic ray flux has been measured with high precision in the energy range from 1010 to 1020.5 eV by several experiments using different techniques. In some energy ranges, it has been possible to determine the flux of individual elements (hydrogen to iron nuclei). This paper explores an astrophysical scenario in which only our Galaxy and the radio galaxy Cen A produce all particles measured on Earth in the energy range from 1010 to 1020.5 eV . Data from AMS-02, CREAM, KASCADE, KASCADE-Grande and the Pierre Auger Observatories are considered. The model developed here is compared to the total and if available to the individual particle flux of the experiments considered.The flux of each element as determined by AMS-02, CREAM, KASCADE and KASCADE-Grande and the mass sensitivity parameter Xmax measured by the Pierre Auger Observatory above 10^ eV are also explored within the framework of the model. The transition from 1016 to 1018 eV is carefully analyzed. It is shown that the flux measured in this energy range suggest the existence of an extra component of cosmic rays yet to be understood.

  3. High resolution laser mass spectrometry bioimaging.

    PubMed

    Murray, Kermit K; Seneviratne, Chinthaka A; Ghorai, Suman

    2016-07-15

    Mass spectrometry imaging (MSI) was introduced more than five decades ago with secondary ion mass spectrometry (SIMS) and a decade later with laser desorption/ionization (LDI) mass spectrometry (MS). Large biomolecule imaging by matrix-assisted laser desorption/ionization (MALDI) was developed in the 1990s and ambient laser MS a decade ago. Although SIMS has been capable of imaging with a moderate mass range at sub-micrometer lateral resolution from its inception, laser MS requires additional effort to achieve a lateral resolution of 10μm or below which is required to image at the size scale of single mammalian cells. This review covers untargeted large biomolecule MSI using lasers for desorption/ionization or laser desorption and post-ionization. These methods include laser microprobe (LDI) MSI, MALDI MSI, laser ambient and atmospheric pressure MSI, and near-field laser ablation MS. Novel approaches to improving lateral resolution are discussed, including oversampling, beam shaping, transmission geometry, reflective and through-hole objectives, microscope mode, and near-field optics. PMID:26972785

  4. Inhibition of Enterovirus 71 (EV-71) Infections by a Novel Antiviral Peptide Derived from EV-71 Capsid Protein VP1

    PubMed Central

    Tan, Chee Wah; Chan, Yoke Fun; Sim, Kooi Mow; Tan, Eng Lee; Poh, Chit Laa

    2012-01-01

    Enterovirus 71 (EV-71) is the main causative agent of hand, foot and mouth disease (HFMD). In recent years, EV-71 infections were reported to cause high fatalities and severe neurological complications in Asia. Currently, no effective antiviral or vaccine is available to treat or prevent EV-71 infection. In this study, we have discovered a synthetic peptide which could be developed as a potential antiviral for inhibition of EV-71. Ninety five synthetic peptides (15-mers) overlapping the entire EV-71 capsid protein, VP1, were chemically synthesized and tested for antiviral properties against EV-71 in human Rhabdomyosarcoma (RD) cells. One peptide, SP40, was found to significantly reduce cytopathic effects of all representative EV-71 strains from genotypes A, B and C tested, with IC50 values ranging from 6–9.3 µM in RD cells. The in vitro inhibitory effect of SP40 exhibited a dose dependent concentration corresponding to a decrease in infectious viral particles, total viral RNA and the levels of VP1 protein. The antiviral activity of SP40 peptide was not restricted to a specific cell line as inhibition of EV-71 was observed in RD, HeLa, HT-29 and Vero cells. Besides inhibition of EV-71, it also had antiviral activities against CV-A16 and poliovirus type 1 in cell culture. Mechanism of action studies suggested that the SP40 peptide was not virucidal but was able to block viral attachment to the RD cells. Substitutions of arginine and lysine residues with alanine in the SP40 peptide at positions R3A, R4A, K5A and R13A were found to significantly decrease antiviral activities, implying the importance of positively charged amino acids for the antiviral activities. The data demonstrated the potential and feasibility of SP40 as a broad spectrum antiviral agent against EV-71. PMID:22563456

  5. A multipolar SR motor and its application in EV

    NASA Astrophysics Data System (ADS)

    Goto, H.; Suzuki, Y.; Nakamura, K.; Watanabe, T.; Guo, H. J.; Ichinokura, O.

    2005-04-01

    In order to bring out the advanced features of EVs, a direct-drive (DD) with in-wheel (IW) layout has been considered, but it requires more motors than the conventional layout and the motors will be used in a hard environment. Because switched reluctance motors (SRMs) are simple and strong, we have developed a new outer-rotor-type multipolar SRM suitable for DD-IW EVs through simulations and experiments. We have implemented the developed SRMs into a prototype EV. This is the first-ever in-vehicle research to our knowledge; the developing process and the road test results will bring many useful guidelines for future developments.

  6. Resonance ionization mass spectrometry of ion beam sputtered neutrals for element- and isotope-selective analysis of plutonium in micro-particles.

    PubMed

    Erdmann, N; Kratz, J-V; Trautmann, N; Passler, G

    2009-11-01

    Micro-particles containing actinides are of interest for risk assessments of contaminated areas, nuclear forensic analyses, and IAEA as well as Euratom safeguards programs. For their analysis, secondary ion mass spectrometry (SIMS) has been established as the state-of-the-art standard technique. In the case of actinide mixtures within the particles, however, SIMS suffers from isobaric interferences (e.g., (238)U/(238)Pu, (241)Am/(241)Pu). This can be eliminated by applying resonance ionization mass spectrometry which is based on stepwise resonant excitation and ionization of atoms with laser light, followed by mass spectrometric detection of the produced ions, combining high elemental selectivity with the analysis of isotopic compositions. This paper describes the instrumental modifications for coupling a commercial time-of-flight (TOF)-SIMS apparatus with three-step resonant post-ionization of the sputtered neutrals using a high-repetition-rate (kHz) Nd:YAG laser pumped tunable titanium:sapphire laser system. Spatially resolved ion images obtained from actinide-containing particles in TOF-SIMS mode demonstrate the capability for isotopic and spatial resolution. Results from three-step resonant post-ionization of bulk Gd and Pu samples successfully demonstrate the high elemental selectivity of this process. PMID:19557397

  7. H2O Adsorption on Graphene(2 × 2): polarization induced renormalization of frontier orbital postions by many-body perturbation theory

    NASA Astrophysics Data System (ADS)

    Ahmadpour Monazam, Mohammadreza; Hingerl, Kurt; Puschnig, Peter

    2015-03-01

    The use as a highly sensitive gas sensor is one of the most fascinating applications of graphene. The adsorbed molecule changes the carrier concentration of graphene and allows to detect even individual molecules. Such applications necessitate an understanding of the adsorption behavior of molecules on graphene. In particular, the energy positions of the frontier orbitals of the adsorbed species with respect to the Fermi level are of prime interest. In this work we studied the interaction of water molecules and graphene by performing ab-initio calculations within the framework of many-body perturbation theory. Our results show that the ionization potential and the affinity level of water are renormalized upon adsorption. This is due to the Coulomb interaction between the added hole or electron and their image charges resulting from a polarization of the substrate. When computing the electronic structure within the GW approximation, we find that the quasi-particle gap of the molecule is reduced by more than 3 eV upon adsorption at the K-point of graphene. Note that these image-charge effects are absent from the most common exchange-correlation functionals used in density functional theory which, for the case of LDA, result in an almost unchanged HOMO-LUMO gap upon adsorption.

  8. Base fluid in improving heat transfer for EV car battery

    NASA Astrophysics Data System (ADS)

    Bin-Abdun, Nazih A.; Razlan, Zuradzman M.; Shahriman, A. B.; Wan, Khairunizam; Hazry, D.; Ahmed, S. Faiz; Adnan, Nazrul H.; Heng, R.; Kamarudin, H.; Zunaidi, I.

    2015-05-01

    This study examined the effects of base fluid (as coolants) channeling inside the heat exchanger in the process of the increase in thermal conductivity between EV car battery and the heat exchanger. The analysis showed that secondary cooling system by means of water has advantages in improving the heat transfer process and reducing the electric power loss on the form of thermal energy from batteries. This leads to the increase in the efficiency of the EV car battery, hence also positively reflecting the performance of the EV car. The present work, analysis is performed to assess the design and use of heat exchanger in increasing the performance efficiency of the EV car battery. This provides a preface to the use this design for nano-fluids which increase and improve from heat transfer.

  9. Large Space Telescope - Orbital crew EV maintenance operations

    NASA Technical Reports Server (NTRS)

    Fisher, H. T.

    1975-01-01

    The paper shows that orbital EV maintenance by the crew has a tremendous impact on several areas of the program, including operations, Shuttle interfaces, support equipment rendezvous and berthing, checkout and verification, levels of servicing achievable, logistics and spares and scientific instruments in order to permit changeout and possible future refurbishment. To achieve on-orbit EV maintenance, such challenges as designing for suited-astronaut access to all subsystem equipment elements, minimization for contamination, handling of extremely sensitive instruments, development of translation techniques, and use of existing GFE and hardware must be faced early in the preliminary design and operations analysis phases. All studies to date indicate that on-orbit EV manned maintenance of the LST (Large Space Telescope) is not only feasible but can be designed to be readily within the capability of the EV functioning astronaut. Both 1-g and neutral buoyancy man-in-the-loop simulations further support this point.

  10. Near Zero ev Subexcitation Energy Electrons Break DNA

    NASA Astrophysics Data System (ADS)

    Martin, Frederic; Cai, Zhongli; Cloutier, Pierre; Hunting, Darel; Sanche, Leon

    2004-03-01

    The passage of ionizing radiation through a living cell produces about 4 x 10^4 electrons/MeV, with more than 50% having energies well below the excitation threshold for water (7-8 eV) (M. Michaud et al, Physical Review, 44(9), 5623-5627, (1991)). We have previously shown that 5-20eV electrons cause DNA strand breaks via a resonant process with a maximum at 10eV (B. Boudaiffa et al, Science 287, 1658-1660, (2000)). The present results demonstrate that very low energy electrons in the range of 0 to 5eV cause single strand breaks (SSB) in DNA. Plasmid DNA is extracted from the host bacteria purified and resuspended in distilled and deionised water. It is deposited on a chemically clean tantalum, lyophilised and placed in an UHV chamber for 24 hours before irradiation. After irradiation, plasmid DNA is retrieved from the UHV chamber and the samples are dissolved in tris buffer. The different topological forms of DNA resulting from single strand break formation are separated by electrophoresis gel, stained by SYBR Green 1, scanned by laser and quantified with the imageQuant program. The quantification protocol has been optimized to maximize both sensitivity and linearity. Two resonant peaks are observed with maxima at 0,8 eV and 2,2 eV ( 10,5 and 7,5 ssb per 10^3 electrons, respectively).

  11. Surface analysis of rubbers and plastics using secondary neutral mass spectrometry.

    SciTech Connect

    Pellin, M. J.; Savina, M. R.

    1999-08-23

    Rubber and plastics are complex mixtures of long-chain polymers, smaller organic additives used as plasticizers, mildicides, fungicides, colorants, etc., and inorganic additives such as carbon and silica. Surface analysis of such materials is at once difficult and important. The difficulty lies in the need to identify specific carbon molecules on a very similar organic surface. The importance arises from the dramatic effect that the distribution and concentration of additives have on the physical properties of polymeric materials. Recently we have had some success in applying laser desorption post-ionization mass spectrometry in measuring the surface concentration and distribution of both additives and the polymer molecules themselves. The key has been to use the photoionization properties of the analyte of interest to augment mass spectrometric information.

  12. A New Bessel-Box Energy Analyzer for Sputtered Neutral Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Yoshikawa, Hideki; Shimizu, Ryuichi

    1990-02-01

    A new type energy analyzer with an electron impact ionizer for sputtered neutral mass spectrometry (SNMS), which is compact enough to be mounted in secondary ion mass spectrometry (SIMS) instruments, has been developed. The compact energy analyzer, called a modified Bessel-Box, enables energy distribution of slow charged particles with different energy resolutions to be obtained by changing the ratio of voltages applied to the analyzer. Applying this system for SNMS of Al-Mg alloy under different partial pressures of oxygen, it has been confirmed that SNMS is free from oxygen enhancement, allowing the quantification of matrix elements with considerable accuracy. It has also been revealed that the space-charge effect caused by bombarding electrons becomes fairly marked, resulting in the deformation and shift of energy distributions of the postionized particles.

  13. Straight and chopped DC performance data for a reliance EV-250AT motor with a General Electric EV-1 controller

    NASA Technical Reports Server (NTRS)

    Edie, P. C.

    1981-01-01

    Straight and chopped DC motor performances for a Reliance EV-250AT motor with an EV-1 controller were examined. Effects of motor temperature and operating voltage are shown. It is found that the maximum motor efficiency is approximately 85% at low operating temperatures in the straight DC mode. Chopper efficiency is 95% under all operating conditions. For equal speeds, the motor operated in the chopped mode develops slightly more torque and draws more current than it does in the straight DC mode.

  14. Investigation of the utility of laser-secondary neutral mass spectrometry for the detection of polyaromatic hydrocarbons in individual atmospheric aerosol particles.

    PubMed

    Tyler, Bonnie J; Dambach, Steffen; Galla, Sebastian; Peterson, Richard E; Arlinghaus, Heinrich F

    2012-01-01

    The distribution of polyaromatic hydrocarbons (PAHs) in ambient aerosol particles is of importance to both human health and climate forcing. Although time-of-flight secondary ion mass spectrometry (ToF-SIMS) has proven useful for studying the distribution of organic compounds in individual aerosol particles, it is difficult to detect PAHs at relevant concentrations in individual aerosol particles because of their low ion yield. In this study, we explore the potential of using laser secondary neutral mass spectrometry (Laser-SNMS) to study three PAHs: pyrene, anthracene, and naphthalene. Because of the high volatility of PAHs, a cryostage was required for the analysis to prevent sublimation of the molecules into the vacuum chamber. We studied two laser systems, a 157 nm excimer laser, which is capable of single-photon ionization of the PAHs, and a 193 nm laser, which requires multiphoton ionization. Under optimized conditions for laser power density and primary ion pulse length, 193 nm postionization resulted in a 2-50-fold increase in ion yield over ToF-SIMS. Using the 157 nm laser, the yield was increased by more than 3 orders of magnitude for all 3 PAHs studied. The single-photon postionization process proved superior in terms of both yield enhancement and reduced fragmentation. By using the optimized 157 nm laser system and a cryostage, we were able to detect PAHs on the surface of 2 μm diameter ambient aerosol particles. PMID:21823569

  15. NASA's Earth Venture-1 (EV-1) Airborne Science Investigations

    NASA Technical Reports Server (NTRS)

    Guillory, A.; Denkins, T.; Allen, B. Danette; Braun, Scott A.; Crawford, James H.; Jensen, Eric J.; Miller, Charles E.; Moghaddam, Mahta; Maring, Hal

    2011-01-01

    In 2010, NASA announced the first Earth Venture (EV-1) selections in response to a recommendation made by the National Research Council for low-cost investigations fostering innovation in Earth science. The five EV-1 investigations span the Earth science focus areas of atmosphere, weather, climate, water and energy and, carbon and represent earth science researchers from NASA as well as other government agencies, academia and industry from around the world. The EV-1 missions are: 1) Airborne Microwave Observatory of Subcanopy and Subsurface (AirMOSS), 2) Airborne Tropical Tropopause Experiment (ATTREX), 3) Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE), 4) Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ), and 5) Hurricane And Severe Storm Sentinel (HS3). The Earth Venture missions are managed out of the Earth System Science Pathfinder (ESSP) Program Office (Allen, et. al. 2010b)

  16. UHM/HNEI EV test and evaluation program

    SciTech Connect

    Not Available

    1992-03-01

    The electric vehicle (EV) program of the Hawaii Natural Energy Institute (HNEI) focuses primarily on the field testing of promising EV/traction batteries. The intent is to utilize typical driving cycles to develop information that verifies or refutes what is obtained in the laboratory. Three different types of battery were assigned by the US DOE for testing in this program: Sonnenschein Dryfit 6V-160, Exide GC-5, Trojan T-145. We added the following battery to the test program: ALCO2200. HNEI's existing EVs were utilized as test beds. The following EVs were chosen in our program: Converted Ford Escort station wagon, Converted Ford Escort two-door sedan, Converted Ford Escort two-door sedan, Converted Dodge van (typically daily driving distances, 10--30 miles). Capacity testing is a very effective way of monitoring the status of battery modules. Based on capacity tests, corrective action such as battery replacement, additional charging, adjusting terminal connections, etc., may be taken to maintain good performance. About 15,500 miles and 600 cycles have been accumulated on the Sonnenschein Dryfit 6V-160 battery pack. Five of its 18 modules have been changed. Based on DOE's standard, the battery has reached the end of its useful life. Nevertheless, the battery pack is still operational and its operating range is still greater than 40 miles per charge. It is too early to evaluate the life expectancy of the other three batteries, the Trojan T-145, Exide GC-5, and Alco 2200. No module has been replaced in these three packs. The Trojan T-145 battery is a very promising EV traction battery in terms of quality and reliability versus price. HNEI will keep the Trojan and Exide battery packs in operation. The Alco 2200 batteries will be transferred to another vehicle. The Additional Charging Method seems to be an effective way of restoring weak modules. The Smart Voltmeter'' developed by HNEI is a promising way of monitoring the remaining range for an EV.

  17. Single ionization of helium by 730-eV electrons

    SciTech Connect

    Stevenson, M. A.; Lohmann, B.; Bray, I.; Fursa, D. V.; Stelbovics, A. T.

    2007-03-15

    We present fully differential measurements of 730-eV electron-impact single ionization of the ground state of helium with 205- or 100-eV outgoing electrons. Internormalized data are obtained for coplanar geometries with the fast electron detected at {theta}{sub A}=6 degree sign , 9 degree sign , and 12 degree sign . The data are compared, where possible, with the corresponding data of Catoire et al. [J. Phys. B 39, 2827 (2006)] and the convergent close-coupling theory. An improved agreement is found between the present measurements and the theory.

  18. The measurement of elemental abundances above 10 sup 15 eV at a lunar base

    SciTech Connect

    Swordy, S.P. )

    1990-03-15

    At {approx}10{sup 15} eV the slope of the energy spectrum of cosmic rays becomes significantly steeper than at lower energies. The measurement of relative elemental abundances at these energies is expected to provide a means to resolve the origin of this feature and greatly contribute to the understanding of the sources of cosmic rays. We describe a moon based detector for making well resolved elemental measurements at these energies using hadronic calorimetry. This detector is particularly well suited for a site on the lunar surface because there is no overlying layer of atmosphere and the large mass required can be provided by the lunar regolith.

  19. The Application of Ultrafast Laser Pulses to Laser Desorption Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Cui, Yang

    Ultrashort femtosecond laser pulses display exceptional performance for the selective ablation of materials, includes metals, semiconductors, and biological tissues. They do not damage the remaining unablated portion of a sample, which permits the possibility of depth profiling by repeat sampling at the same location. With sufficiently micro-focused fs laser pulse length beam, high lateral resolution mass spectrometry imaging is possible, while sample damage may degrade ultimate lateral resolution in some other methods. Combining imaging and depth profiling could ultimately leads to tomographical mass spectrometry or 3D imaging MS. Laser postionization, a "soft" ionization method, was combined with ultrafast laser desorption for enhanced molecular analysis. A customized femtosecond laser desorption/ablation postionization time-of-flight mass spectrometer was designed and built. The construction and performance of both phases including the VUV source are detailed. Instrument control software was written to operate this instrument, and many automated experiments were successfully demonstrated by this software. Elemental and molecular analysis was carried out on the instrument and demonstrated exceptional performance for fs laser pulse sampling of small areas. Studies demonstrated the imaging and depth profiling capability of fs-LDPI on metals, semiconductors and intact biofilm tissues. Attempts were made to reach the limit of lateral resolution of imaging by fs-LDPI-MS. The results showed similar lateral resolution of <2 mum for both fs 800 nm and 400 nm desorption beams. To improve the repetition rate for high speed imaging application, an alternative LDPI scheme was designed and constructed. The fs 800 beam was tripled to 267 nm and delivered into the ion source as an ionization laser, while a ns 349 nm pulse laser was used for desorption. Preliminary data showed certain intact molecular ions can be detected. Fragmentation tendency was measured against various

  20. Absolute neutrino mass measurements

    NASA Astrophysics Data System (ADS)

    Wolf, Joachim

    2011-10-01

    The neutrino mass plays an important role in particle physics, astrophysics and cosmology. In recent years the detection of neutrino flavour oscillations proved that neutrinos carry mass. However, oscillation experiments are only sensitive to the mass-squared difference of the mass eigenvalues. In contrast to cosmological observations and neutrino-less double beta decay (0v2β) searches, single β-decay experiments provide a direct, model-independent way to determine the absolute neutrino mass by measuring the energy spectrum of decay electrons at the endpoint region with high accuracy. Currently the best kinematic upper limits on the neutrino mass of 2.2eV have been set by two experiments in Mainz and Troitsk, using tritium as beta emitter. The next generation tritium β-experiment KATRIN is currently under construction in Karlsruhe/Germany by an international collaboration. KATRIN intends to improve the sensitivity by one order of magnitude to 0.2eV. The investigation of a second isotope (137Rh) is being pursued by the international MARE collaboration using micro-calorimeters to measure the beta spectrum. The technology needed to reach 0.2eV sensitivity is still in the R&D phase. This paper reviews the present status of neutrino-mass measurements with cosmological data, 0v2β decay and single β-decay.

  1. Absolute neutrino mass measurements

    SciTech Connect

    Wolf, Joachim

    2011-10-06

    The neutrino mass plays an important role in particle physics, astrophysics and cosmology. In recent years the detection of neutrino flavour oscillations proved that neutrinos carry mass. However, oscillation experiments are only sensitive to the mass-squared difference of the mass eigenvalues. In contrast to cosmological observations and neutrino-less double beta decay (0v2{beta}) searches, single {beta}-decay experiments provide a direct, model-independent way to determine the absolute neutrino mass by measuring the energy spectrum of decay electrons at the endpoint region with high accuracy.Currently the best kinematic upper limits on the neutrino mass of 2.2eV have been set by two experiments in Mainz and Troitsk, using tritium as beta emitter. The next generation tritium {beta}-experiment KATRIN is currently under construction in Karlsruhe/Germany by an international collaboration. KATRIN intends to improve the sensitivity by one order of magnitude to 0.2eV. The investigation of a second isotope ({sup 137}Rh) is being pursued by the international MARE collaboration using micro-calorimeters to measure the beta spectrum. The technology needed to reach 0.2eV sensitivity is still in the R and D phase. This paper reviews the present status of neutrino-mass measurements with cosmological data, 0v2{beta} decay and single {beta}-decay.

  2. Observations from The EV Project in Q4 2013

    SciTech Connect

    John Smart

    2014-02-01

    This is a summary report for The EV Project 4th quarter 2013 reports. It describes electric vehicle driver driving and charging behavior observed in Q4. It is the same report as the previously approved/published Q3 2013 report, only the numbers have been updated. It is for public release and does not have limited distribution.

  3. The genome of the Lactobacillus sanfranciscensis temperate phage EV3

    PubMed Central

    2013-01-01

    Background Bacteriophages infection modulates microbial consortia and transduction is one of the most important mechanism involved in the bacterial evolution. However, phage contamination brings food fermentations to a halt causing economic setbacks. The number of phage genome sequences of lactic acid bacteria especially of lactobacilli is still limited. We analysed the genome of a temperate phage active on Lactobacillus sanfranciscensis, the predominant strain in type I sourdough fermentations. Results Sequencing of the DNA of EV3 phage revealed a genome of 34,834 bp and a G + C content of 36.45%. Of the 43 open reading frames (ORFs) identified, all but eight shared homology with other phages of lactobacilli. A similar genomic organization and mosaic pattern of identities align EV3 with the closely related Lactobacillus vaginalis ATCC 49540 prophage. Four unknown ORFs that had no homologies in the databases or predicted functions were identified. Notably, EV3 encodes a putative dextranase. Conclusions EV3 is the first L. sanfranciscensis phage that has been completely sequenced so far. PMID:24308641

  4. Philosophical Adventures in the Lands of Oz and Ev

    ERIC Educational Resources Information Center

    Matthews, Gareth B.

    2009-01-01

    In this article, the author talks about the philosophical adventures of the characters in L. Frank Baum's Lands of Oz and Ev stories and discusses how such stories can stimulate reflections on philosophically interesting questions. Frank Baum is considered as the first American writer of philosophical fantasy for children for writing "The…

  5. High-frequency electron-gas secondary neutral mass spectrometry: evaluation of transient effects

    NASA Astrophysics Data System (ADS)

    Krimke, Ralf; Urbassek, Herbert M.; Wucher, Andreas

    1997-06-01

    In electron-gas secondary neutral mass spectrometry (SNMS), a low-pressure plasma serves both as an ion source for sputter depth profiling the target and for post-ionizing the sputtered neutrals. In its high-frequency mode, a rectangular RF bias is applied to the target. We investigate by PIC/MC kinetic simulation the processes occurring in the vicinity of the substrate as a consequence of the voltage jumps: sheath expansion and contraction, as well as flux and energy of the ions impinging onto the substrate. In particular, we determine the enhancement of the ion current shortly after negatively charging the substrate; this enhancement is due to the acceleration of the large ion population in the expanding sheath. Our results indicate that already at a switch frequency of only 1 MHz the surface treatment by rectangularly shaped RF potentials is dominated by transient effects.

  6. Standardization of time-of-flight laser ionization mass spectrometry analysis of minerals

    NASA Astrophysics Data System (ADS)

    Dimov, S. S.; Chryssoulis, S. L.

    1998-03-01

    The standardization of the time-of-flight laser ionization mass spectrometry (TOF-LIMS) analysis of mineral surfaces is an important step towards providing reproducible quantitative data. This paper reports the search for experimental conditions and instrumental configurations that provide efficient ionization for all elements of the sample. For that purpose, an investigation of the neutral emission dynamics and the ion yields for the most important elements, as a function of laser power densities, the relative time delay between the ablation and postionization processes, and the sample matrix, was performed. In order to standardize the procedure, an empirical protocol was established, based on the use of optimized system parameters to monitor the ion yield from a library of standard reference samples.

  7. Methane ice photochemistry and kinetic study using laser desorption time-of-flight mass spectrometry at 20 K.

    PubMed

    Bossa, J-B; Paardekooper, D M; Isokoski, K; Linnartz, H

    2015-07-14

    The ice photochemistry of pure methane (CH4) is studied at 20 K upon VUV irradiation from a microwave discharge H2 flow lamp. Laser Desorption Post-Ionization Time-Of-Flight Mass Spectrometry (LDPI TOF-MS) is used for the first time to determine branching ratios of primary reactions leading to CH3, CH2, and CH radicals, typically for fluences as expected in space. This study is based on a stable end-products analysis and the mass spectra are interpreted using an appropriate set of coupled reactions and rate constants. This yields clearly different values from previous gas phase studies. The matrix environment as well as the higher efficiency of reverse reactions in the ice clearly favor CH3 radical formation as the main first generation photoproduct. PMID:26073296

  8. Imaging of polycyclic aromatic hydrocarbons by means of sputtered neutrals mass spectrometry using a diode-pumped solid-state laser.

    PubMed

    Ohishi, Kenji; Sakamoto, Tetsuo; Saikawa, Jiro; Ishigaki, Naoya; Tojo, Koji; Ido, Yutaka; Hayashi, Shun-ichi; Ishiuchi, Shun-ichi; Misawa, Kentaro; Fujii, Masaaki

    2013-01-01

    Laser post-ionization of sputtered molecules by pulsed Ga focused ion-beam (Ga-FIB) bombardment was examined for the detection and imaging of polycyclic aromatic hydrocarbons (PAHs) on particles. As model samples, pyrene and pelyrene adsorbed on TiO2, blended regents of pyrene and n-heneicosan were used. The TiO2 particle size was selected to be several micro-meters. Laser light and Ga-FIB were synchronized with each other. The repetition rate synchronized with Ga-FIB was 1 kHz for pyrene analysis and 2 kHz for perylene, respectively. The laser wavelength was set to 266 nm. The wavelength was a generated fourth harmonic of a Nd:YAG DPSS (diode-pumped solid-state) micro-chip laser (UV microchip laser). By using a UV microchip laser, laser-SNMS (laser post-ionized sputtered neutral mass spectrometry) analysis and imaging were performed. The imaging of pyrene (m/z = 202, C16H10) and perylene (m/z = 252, C20H12) has been successful. Both the scanning ion microscopy image of TiO2 and the PAHs image in laser-SNMS analysis were well-fitted with each other. PMID:23474717

  9. Secondary Ion Mass Spectrometry SIMS XI

    NASA Astrophysics Data System (ADS)

    Gillen, G.; Lareau, R.; Bennett, J.; Stevie, F.

    2003-05-01

    This volume contains 252 contributions presented as plenary, invited and contributed poster and oral presentations at the 11th International Conference on Secondary Ion Mass Spectrometry (SIMS XI) held at the Hilton Hotel, Walt Disney World Village, Orlando, Florida, 7 12 September, 1997. The book covers a diverse range of research, reflecting the rapid growth in advanced semiconductor characterization, ultra shallow depth profiling, TOF-SIMS and the new areas in which SIMS techniques are being used, for example in biological sciences and organic surface characterization. Papers are presented under the following categories: Isotopic SIMS Biological SIMS Semiconductor Characterization Techniques and Applications Ultra Shallow Depth Profiling Depth Profiling Fundamental/Modelling and Diffusion Sputter-Induced Topography Fundamentals of Molecular Desorption Organic Materials Practical TOF-SIMS Polyatomic Primary Ions Materials/Surface Analysis Postionization Instrumentation Geological SIMS Imaging Fundamentals of Sputtering Ion Formation and Cluster Formation Quantitative Analysis Environmental/Particle Characterization Related Techniques These proceedings provide an invaluable source of reference for both newcomers to the field and experienced SIMS users.

  10. Study of model dependence of EAS simulations at E>_1019 EV.

    NASA Astrophysics Data System (ADS)

    Heck, D.; Knapp, J.; Sciutto, S. J.

    Air shower simulation programs are essential tools for the analysis of data from present and future cosmic ray experiments, since estimates of energy and mass of the primary particle can only be obtained by comparison to model predictions, and the model uncertainties translate directly into systematic errors in the energy and mass determination. While the main uncertainty of contemporary models comes from our poor knowledge of the (soft) hadronic interactions at high energies, also electromagnetic interactions, low-energy hadronic interactions and the particle transport influence details of the shower development. We report here on a comparative analysis of simulations for 2 × 1019 eV protons, performed with the AIRES and CORSIKA air shower simulation programs. The model dependency of the main shower observables is discussed. We study also some aspects of the technical performance of both programs.

  11. UHM/HNEI EV test and evaluation program. Final report

    SciTech Connect

    Not Available

    1992-03-01

    The electric vehicle (EV) program of the Hawaii Natural Energy Institute (HNEI) focuses primarily on the field testing of promising EV/traction batteries. The intent is to utilize typical driving cycles to develop information that verifies or refutes what is obtained in the laboratory. Three different types of battery were assigned by the US DOE for testing in this program: Sonnenschein Dryfit 6V-160, Exide GC-5, Trojan T-145. We added the following battery to the test program: ALCO2200. HNEI`s existing EVs were utilized as test beds. The following EVs were chosen in our program: Converted Ford Escort station wagon, Converted Ford Escort two-door sedan, Converted Ford Escort two-door sedan, Converted Dodge van (typically daily driving distances, 10--30 miles). Capacity testing is a very effective way of monitoring the status of battery modules. Based on capacity tests, corrective action such as battery replacement, additional charging, adjusting terminal connections, etc., may be taken to maintain good performance. About 15,500 miles and 600 cycles have been accumulated on the Sonnenschein Dryfit 6V-160 battery pack. Five of its 18 modules have been changed. Based on DOE`s standard, the battery has reached the end of its useful life. Nevertheless, the battery pack is still operational and its operating range is still greater than 40 miles per charge. It is too early to evaluate the life expectancy of the other three batteries, the Trojan T-145, Exide GC-5, and Alco 2200. No module has been replaced in these three packs. The Trojan T-145 battery is a very promising EV traction battery in terms of quality and reliability versus price. HNEI will keep the Trojan and Exide battery packs in operation. The Alco 2200 batteries will be transferred to another vehicle. The Additional Charging Method seems to be an effective way of restoring weak modules. The ``Smart Voltmeter`` developed by HNEI is a promising way of monitoring the remaining range for an EV.

  12. Ellipsometry and energy characterization of the electron impact polymerization in the range 0-20 eV

    NASA Astrophysics Data System (ADS)

    Zyn, V. I.

    2016-05-01

    The electron impact polymerization of adsorbed vapors of a hydrocarbon vacuum oil with molecular mass 450 Da (C32H66) has been studied in-situ in the range 0-20 eV using ellipsometry and a servo system with the Kelvin's vibrating probe. This allowed registering at the same time the two energy-dependent characteristics (spectra) of the process: the film growth rate and the electrical potential of the irradiated surface. The first spectrum has two resonance maxima near 2.5 and 9.5 eV while the surface potential has only one weak extremum near 9.5 eV. The first growth rate peak at 2.5 eV was connected with a creation of radicals through a resonant process of the dissociative electron attachment and beginning polymerization. The peaks at 9.5 eV in both the spectra mean accelerating polymerization and decreasing surface charge owing to simultaneous birth of highly active radicals and free electrons. The single resonant process controlling both the processes simultaneously is the dissociative attachment of an electron to an anti-bonding molecular orbital, almost the same as at the 2.5 eV but differing by deeper decomposition of the transient anion, among the products of which are now not the radicals only but also free electrons. The kinetic curves obtained in pulsed regimes of the electron bombardment were qualitatively identical for different precursors and were used for calculations of cross sections of these processes.

  13. Cascades from nu_E above 1020 eV

    SciTech Connect

    Klein, Spencer R.

    2004-12-21

    At very high energies, the Landau-Pomeranchuk-Migdal effect reduces the cross sections for electron bremsstrahlung and photon e{sup +}e{sup -} pair production. The fractional electron energy loss and pair production cross sections drop as the energy increases. In contrast, the cross sections for photonuclear interactions grow with energy. In solids and liquids, at energies above 10{sup 20} eV, photonuclear reactions dominate, and showers that originate as photons or electrons quickly become hadronic showers. These electron-initiated hadronic showers are much shorter (due to the absence of the LPM effect), but wider than purely electromagnetic showers would be. This change in shape alters the spectrum of the electromagnetic and acoustic radiation emitted from the shower. These alterations have important implications for existing and planned searches for radiation from u{sub e} induced showers above 10{sup 20} eV, and some existing limits should be reevaluated.

  14. Enhanced detection of LED runway/approach lights for EVS

    NASA Astrophysics Data System (ADS)

    Kerr, J. Richard

    2008-04-01

    The acquisition of approach and runway lights by an imager is critical to landing-credit operations with EVS. Using a GPS clock, LED sources are pulsed at one-half the EVS video rate of 60 Hz or more. The camera then uses synchronous (lock-in) detection to store the imaged lights in alternate frames, with digital subtraction of the background for each respective frame-pair. Range and weather penetration, limited only by detector background shot-noise (or camera system noise at night), substantially exceed that of the human eye. An alternative is the use of short-wave infrared cameras with eyesafe laser diode emitters. Also, runway identification may be encoded on the pulses. With standardized cameras and emitters, an "instrument qualified visual range" may be established. The concept extends to portable beacons at austere airfields, and to see-and-avoid sensing of other aircraft including UAVs.

  15. Archaeology management system based on EV-Globe

    NASA Astrophysics Data System (ADS)

    Yang, Lin; Lu, Guo-nian; Pei, An-ping; Niu, Yu-gang; Luo, Tao

    2008-10-01

    Traditionally, cultural relics were recorded in a 2D (2 dimensions) method such as paper maps, pictures, multi-media, micro-models and so on. This paper introduces the archaeology management system based on EV-Globe (Earth View-Globe - spatial information service platform on virtual 3D environment) for the cultural relics along the Eastern Route Project (ERP) of South-to-North Water Diversion (SNWD). Integrate the spatial and attribute data of the cultural relics along ERP of SNWD processed by SuperMap deskpro2005 with the relative basic geological data based on the platform of EV-Globe and develop a series of functions based on the SDK (Software Development Kit), and so the relics can be managed visually, at the same time the system may assist the archaeologists and some researchers in managing and studying the cultural relics. Some conception and conceiving of web and mobile version is put forward for next researching.

  16. Observations from The EV Project in Q3 2013

    SciTech Connect

    John Smart

    2013-12-01

    This is a brief report that summarizes results published in numerous other reports. It describes the usage of electric vehicles and charging units in the EV Project over the past 3 months. There is no new data or information provided in this report, only summarizing of information published in other reports (which have all been approved for unlimited distribution publication). This report will be posted to the INL/AVTA website for viewing by the general public.

  17. Ionization of rubidium by 50-eV electrons

    SciTech Connect

    Haynes, M.A.; Lohmann, B.; Bray, I.; Bartschat, K.

    2004-04-01

    We report on a joint experimental and theoretical study of 50-eV electron-impact ionization of rubidium. Comparison of the experimental data with theoretical predictions from various models shows good qualitative agreement, as long as distortion and channel-coupling effects in the projectile-target interaction are accounted for. The remaining differences between experiment and theory indicate the need for further studies of this collision system.

  18. BEV Charging Behavior Observed in The EV Project for 2013

    SciTech Connect

    Brion D. Bennett

    2014-01-01

    This fact sheet will be issued quarterly to report on the number of Nissan Leafs vehicle usage, charging locations, and charging completeness as part of the EV Project. It will be posted on the INL/AVTA and ECOtality websites and will be accessible by the general public. The raw data that is used to create the report is considered proprietary/OUO and NDA protected, but the information in this report is NOT proprietary nor NDA protected.

  19. The EvA study: aims and strategy.

    PubMed

    Ziegler-Heitbrock, Loems; Frankenberger, Marion; Heimbeck, Irene; Burggraf, Dorothe; Wjst, Matthias; Häussinger, Karl; Brightling, Chris; Gupta, Sumit; Parr, David; Subramanian, Deepak; Singh, Dave; Kolsum, Umme; Boschetto, Piera; Potena, Alfredo; Gorecka, Dorota; Nowinski, Adam; Barta, Imre; Döme, Balazs; Strausz, Janos; Greulich, Timm; Vogelmeier, Claus; Bals, Robert; Hohlfeld, Jens M; Welte, Tobias; Venge, Per; Gut, Ivo; Boland, Anne; Olaso, Robert; Hager, Jörg; Hiemstra, Pieter; Rabe, Klaus F; Unmüssig, Martina; Müller-Quernheim, Joachim; Prasse, Antje

    2012-10-01

    The EvA study is a European Union-funded project under the Seventh Framework Programme (FP7), which aims at defining new markers for chronic obstructive pulmonary disease (COPD) and its subtypes. The acronym is derived from emphysema versus airway disease, indicating that the project targets these two main phenotypes of the disease. The EvA study is based on the concept that emphysema and airway disease are governed by different pathophysiological processes, are driven by different genes and have differential gene expression in the lung. To define these genes, patients and non-COPD controls are recruited for clinical examination, lung function analysis and computed tomography (CT) of the lung. CT scans are used to define the phenotypes based on lung density and airway wall thickness. This is followed by bronchoscopy in order to obtain samples from the airways and the alveoli. These tissue samples, along with blood samples, are then subjected to genome-wide expression and association analysis and markers linked to the phenotypes are identified. The population of the EvA study is different from other COPD study populations, since patients with current oral glucocorticoids, antibiotics and exacerbations or current smokers are excluded, such that the signals detected in the molecular analysis are due to the distinct inflammatory process of emphysema and airway disease in COPD. PMID:22441733

  20. Intelligent Vehicle Charging Benefits Assessment Using EV Project Data

    SciTech Connect

    Letendre, Steven; Gowri, Krishnan; Kintner-Meyer, Michael CW; Pratt, Richard M.

    2013-12-01

    PEVs can represent a significant power resource for the grid. An IVCI with bi-direction V2G capabilities would allow PEVs to provide grid support services and thus generate a source of revenue for PEV owners. The fleet of EV Project vehicles represents a power resource between 30 MW and 90 MW, depending on the power rating of the grid connection (5-15 kW). Aggregation of vehicle capacity would allow PEVs to participate in wholesale reserve capacity markets. One of the key insights from EV Project data is the fact that vehicles are connected to an EVSE much longer than is necessary to deliver a full charge. During these hours when the vehicles are not charging, they can be participating in wholesale power markets providing the high-value services of regulation and spinning reserves. The annual gross revenue potential for providing these services using the fleet of EV Project vehicles is several hundred thousands of dollars to several million dollars annually depending on the power rating of the grid interface, the number of hours providing grid services, and the market being served. On a per vehicle basis, providing grid services can generate several thousands of dollars over the life of the vehicle.

  1. Battery Electric Vehicle Driving and Charging Behavior Observed Early in The EV Project

    SciTech Connect

    John Smart; Stephen Schey

    2012-04-01

    As concern about society's dependence on petroleum-based transportation fuels increases, many see plug-in electric vehicles (PEV) as enablers to diversifying transportation energy sources. These vehicles, which include plug-in hybrid electric vehicles (PHEV), range-extended electric vehicles (EREV), and battery electric vehicles (BEV), draw some or all of their power from electricity stored in batteries, which are charged by the electric grid. In order for PEVs to be accepted by the mass market, electric charging infrastructure must also be deployed. Charging infrastructure must be safe, convenient, and financially sustainable. Additionally, electric utilities must be able to manage PEV charging demand on the electric grid. In the Fall of 2009, a large scale PEV infrastructure demonstration was launched to deploy an unprecedented number of PEVs and charging infrastructure. This demonstration, called The EV Project, is led by Electric Transportation Engineering Corporation (eTec) and funded by the U.S. Department of Energy. eTec is partnering with Nissan North America to deploy up to 4,700 Nissan Leaf BEVs and 11,210 charging units in five market areas in Arizona, California, Oregon, Tennessee, and Washington. With the assistance of the Idaho National Laboratory, eTec will collect and analyze data to characterize vehicle consumer driving and charging behavior, evaluate the effectiveness of charging infrastructure, and understand the impact of PEV charging on the electric grid. Trials of various revenue systems for commercial and public charging infrastructure will also be conducted. The ultimate goal of The EV Project is to capture lessons learned to enable the mass deployment of PEVs. This paper is the first in a series of papers documenting the progress and findings of The EV Project. This paper describes key research objectives of The EV Project and establishes the project background, including lessons learned from previous infrastructure deployment and PEV

  2. Circular intensity differential scattering measurements in the soft x-ray region of the spectrum (~16 EV to 500 EV)

    NASA Astrophysics Data System (ADS)

    Maestre, Marcos F.; Bustamante, Carlos J.; Snyder, Patricia A.; Rowe, Ednor M.; Hansen, Roger W.

    1991-11-01

    We propose the use of recently developed technique of circular intensity differential scattering (CIDS), as extended to the soft x-ray region of the spectrum (16 eV to 500 eV), to study the higher order organization of the eukaryotic chromosome. CIDS is the difference in scattering power of an object when illuminated by right circularly polarized vs. left circularly polarized electromagnetic radiation of arbitrary wavelength. CIDS has been shown to be a very sensitive measure of the helical organization of the scattering object, e.g., the eukaryotic chromosome. Preliminary results of measurements of samples of bacteriophages and octopus sperm done at SRC, Wisconsin, show the technique to be very sensitive to the dimensional parameters of the particles interrogated by circularly polarized light.

  3. New constraints on neutrino masses from cosmology

    SciTech Connect

    Melchiorri, A.; Serra, P.; Dodelson, S.; Slosar, A.; /Ljubljana U.

    2006-01-01

    By combining data from cosmic microwave background (CMB) experiments (including the recent WMAP third year results), large scale structure (LSS) and Lyman-{alpha} forest observations, we derive upper limits on the sum of neutrino masses of {summation}m{sub v} < 0.17eV at 95% c.l.. We then constrain the hypothesis of a fourth, sterile, massive neutrino. For the 3 massless + 1 massive neutrino case we bound the mass of the sterile neutrino to m{sub s} < 0.26eV at 95% c.l.. These results exclude at high significance the sterile neutrino hypothesis as an explanation of the LSND anomaly. We then generalize the analysis to account for active neutrino masses which tightens the limit to m{sub s} < 0.23eV and the possibility that the sterile abundance is not thermal. In the latter case, the constraints in the (mass, density) plane are nontrivial. For a mass of > 1eV or < 0.05eV the cosmological energy density in sterile neutrinos is always constrained to be {omega}{sub v} < 0.003 at 95% c.l.. However, for a sterile neutrino mass of {omega}{sub v} 0.25eV, {omega}{sub v} can be as large as 0.01.

  4. Torque blending and wheel slip control in EVs with in-wheel motors

    NASA Astrophysics Data System (ADS)

    de Castro, Ricardo; Araújo, Rui E.; Tanelli, Mara; Savaresi, Sergio M.; Freitas, Diamantino

    2012-01-01

    Among the many opportunities offered by electric vehicles (EVs), the design of power trains based on in-wheel electric motors represents, from the vehicle dynamics point of view, a very attractive prospect, mainly due to the torque-vectoring capabilities. However, this distributed propulsion also poses some practical challenges, owing to the constraints arising from motor installation in a confined space, to the increased unsprung mass weight and to the integration of the electric motor with the friction brakes. This last issue is the main theme of this work, which, in particular, focuses on the design of the anti-lock braking system (ABS). The proposed structure for the ABS is composed of a tyre slip controller, a wheel torque allocator and a braking supervisor. To address the slip regulation problem, an adaptive controller is devised, offering robustness to uncertainties in the tyre-road friction and featuring a gain-scheduling mechanism based on the vehicle velocity. Further, an optimisation framework is employed in the torque allocator to determine the optimal split between electric and friction brake torque based on energy performance metrics, actuator constraints and different actuators bandwidth. Finally, based on the EV working condition, the priorities of this allocation scheme are adapted by the braking supervisor unit. Simulation results obtained with the CarSim vehicle model, demonstrate the effectiveness of the overall approach.

  5. Secondary Use of PHEV and EV Batteries: Opportunities & Challenges (Presentation)

    SciTech Connect

    Neubauer, J.; Pesaran, A.; Howell, D.

    2010-05-01

    NREL and partners will investigate the reuse of retired lithium ion batteries for plug-in hybrid, hybrid, and electric vehicles in order to reduce vehicle costs and emissions and curb our dependence on foreign oil. A workshop to solicit industry feedback on the process is planned. Analyses will be conducted, and aged batteries will be tested in two or three suitable second-use applications. The project is considering whether retired PHEV/EV batteries have value for other applications; if so, what are the barriers and how can they be overcome?

  6. Assessment of battery technologies for EV (Electric Vehicle) applications

    NASA Astrophysics Data System (ADS)

    Ratner, Elliot Z.; Henriksen, Gary L.; Warde, Charles J.

    To guide future R and D program planning, the U.S. Department of Energy (DOE) commissioned an assessment of all viable battery techniques for EV applications. Sixty-seven technology developers in the United States, Canada, Europe, Asia, and Africa were solicited to design a power pack for an Improved Dual-Shaft Electric Propulsions (IDSEP) van. A team of 10 consultants and 8 representatives from DOE's National Laboratories evaluated 43 developer responses and consultant-prepared conceptual designs. Using six criteria---five technical/economic criteria and a maturity/technical barriers criterion---the assessment identified 12 most promising battery technologies.

  7. Protective effect of enterovirus‑71 (EV71) virus‑like particle vaccine against lethal EV71 infection in a neonatal mouse model.

    PubMed

    Cao, Lei; Mao, Fengfeng; Pang, Zheng; Yi, Yao; Qiu, Feng; Tian, Ruiguang; Meng, Qingling; Jia, Zhiyuan; Bi, Shengli

    2015-08-01

    Enterovirus-71 (EV71) is a viral pathogen that causes severe cases of hand, foot and mouth disease (HFMD) among young children, with significant mortality. Effective vaccines against HFMD are urgently required. Several EV71 virus-like particle (VLP) vaccine candidates were found to be protective in the neonatal mouse EV71 challenge model. However, to what extent the VLP vaccine protects susceptible organs against EV71 infection in vivo has remained elusive. In the present study, the comprehensive immunogenicity of a potential EV71 vaccine candidate based on VLPs was evaluated in a neonatal mouse model. Despite lower levels of neutralizing antibodies to EV71 in the sera of VLP-immunized mice compared with those in mice vaccinated with inactivated EV71, the VLP-based vaccine was shown to be able to induce immunoglobulin (Ig)G and IgA memory-associated cellular immune responses to EV71. Of note, the EV71 VLP vaccine candidate was capable of inhibiting viral proliferation in cardiac muscle, skeletal muscle, lung and intestine of immunized mice and provided effective protection against the pathological damage caused by viral attack. In particular, the VLP vaccine was able to inhibit the transportation of EV71 from the central nervous system to the muscle tissue and greatly protected muscle tissue from infection, along with recovery from the viral infection. This led to nearly 100% immunoprotective efficacy, enabling neonatal mice delivered by VLP-immunized female adult mice to survive and grow with good health. The present study provided valuable additional knowledge of the specific protective efficacy of the EV71 VLP vaccine in vivo, which also indicated that it is a promising potential candidate for being developed into an EV71 vaccine. PMID:25936344

  8. Protective effect of enterovirus-71 (EV71) virus-like particle vaccine against lethal EV71 infection in a neonatal mouse model

    PubMed Central

    CAO, LEI; MAO, FENGFENG; PANG, ZHENG; YI, YAO; QIU, FENG; TIAN, RUIGUANG; MENG, QINGLING; JIA, ZHIYUAN; BI, SHENGLI

    2015-01-01

    Enterovirus-71 (EV71) is a viral pathogen that causes severe cases of hand, foot and mouth disease (HFMD) among young children, with significant mortality. Effective vaccines against HFMD are urgently required. Several EV71 virus-like particle (VLP) vaccine candidates were found to be protective in the neonatal mouse EV71 challenge model. However, to what extent the VLP vaccine protects susceptible organs against EV71 infection in vivo has remained elusive. In the present study, the comprehensive immunogenicity of a potential EV71 vaccine candidate based on VLPs was evaluated in a neonatal mouse model. Despite lower levels of neutralizing antibodies to EV71 in the sera of VLP-immunized mice compared with those in mice vaccinated with inactivated EV71, the VLP-based vaccine was shown to be able to induce immunoglobulin (Ig)G and IgA memory-associated cellular immune responses to EV71. Of note, the EV71 VLP vaccine candidate was capable of inhibiting viral proliferation in cardiac muscle, skeletal muscle, lung and intestine of immunized mice and provided effective protection against the pathological damage caused by viral attack. In particular, the VLP vaccine was able to inhibit the transportation of EV71 from the central nervous system to the muscle tissue and greatly protected muscle tissue from infection, along with recovery from the viral infection. This led to nearly 100% immunoprotective efficacy, enabling neonatal mice delivered by VLP-immunized female adult mice to survive and grow with good health. The present study provided valuable additional knowledge of the specific protective efficacy of the EV71 VLP vaccine in vivo, which also indicated that it is a promising potential candidate for being developed into an EV71 vaccine. PMID:25936344

  9. THERMAL CONDUCTIVITY AND ELEMENT FRACTIONATION IN EV Lac

    SciTech Connect

    Laming, J. Martin; Hwang, Una

    2009-12-10

    We present a 100 ks Suzaku observation of the dMe flare star EV Lac, in which the star was captured undergoing a moderate 1500 s flare. During the flare, the count rate increased by about a factor of 50 and the spectrum showed overall enhanced element abundances relative to quiescence. While the quiescent element abundances confirm the inverse first ionization potential (FIP) effect previously documented for EV Lac, with relatively higher depletions for low FIP elements, abundances during the flare spectra show a composition closer to that of the stellar photosphere. We discuss these results in the context of models that explain abundance fractionation in the stellar chromosphere as a result of the ponderomotive force due to Alfven waves. Stars with FIP or inverse FIP effects arising from differently directed ponderomotive forces may have quite different abundance signatures in their evaporated chromospheric plasma during flares, if the same ponderomotive force also affects thermal conduction downward from the corona. The regulation of the thermal conductivity by the ponderomotive force requires a level of turbulence that is somewhat higher than is normally assumed, but plausible in filamentary conduction models.

  10. Thermal Conductivity and Element Fractionation in EV Lac

    NASA Astrophysics Data System (ADS)

    Laming, J. Martin; Hwang, Una

    2009-12-01

    We present a 100 ks Suzaku observation of the dMe flare star EV Lac, in which the star was captured undergoing a moderate 1500 s flare. During the flare, the count rate increased by about a factor of 50 and the spectrum showed overall enhanced element abundances relative to quiescence. While the quiescent element abundances confirm the inverse first ionization potential (FIP) effect previously documented for EV Lac, with relatively higher depletions for low FIP elements, abundances during the flare spectra show a composition closer to that of the stellar photosphere. We discuss these results in the context of models that explain abundance fractionation in the stellar chromosphere as a result of the ponderomotive force due to Alfvén waves. Stars with FIP or inverse FIP effects arising from differently directed ponderomotive forces may have quite different abundance signatures in their evaporated chromospheric plasma during flares, if the same ponderomotive force also affects thermal conduction downward from the corona. The regulation of the thermal conductivity by the ponderomotive force requires a level of turbulence that is somewhat higher than is normally assumed, but plausible in filamentary conduction models.

  11. Energetic (above 60 eV) atmospheric photoelectrons

    NASA Technical Reports Server (NTRS)

    Winningham, J. D.; Decker, D. T.; Kozyra, J. U.; Nagy, A. F.; Jasperse, J. R.

    1989-01-01

    Data from low altitude plasma instrument (LAPI) on Dynamics Explorer 2 document a population of high-energy (up to 800 eV) atmospheric photoelectrons that has not been reported in the published literature. The source of these photoelectrons is postulated to be the soft X-ray portion of the whole sun spectrum. This conclusion is supported by sunrise-sunset characteristics that track those of the classical (below 60 eV) EUV-produced photoelectrons, and theoretical results from two models that incorporate the soft X-ray portion of the solar spectrum. The models include K-shell ionization effects and predict peaks in the photoelectron spectrum due to Auger electrons emitted from oxygen and nitrogen. The peak for nitrogen is observed as predicted, but the peak for oxygen is barely observable. Excellent quantitative agreement is achieved between theory and experiment by using reasonable adjustments to the few published soft X-ray spectra based on solar activity. The upflowing energetic photoelectrons provide a heretofore unknown source of electrons to the magnetosphere. They occur whenever and wherever the sun is up, that is, at all invariant latitudes. Their density is low, but they are steady and ubiquitous. If scattering and trapping occur on closed field lines, then photoelectrons could contribute as a significant particle source and thus represent a new facet of magnetosphere-ionosphere coupling.

  12. Reaction dynamics of H + O2 at 1.6 eV collision energy

    NASA Technical Reports Server (NTRS)

    Bronikowski, Michael J.; Rong, Zhang; Rakestraw, David J.; Zare, Richard N.

    1989-01-01

    The hot hydrogen atom reaction, H + O2 yields OH + O, has been studied at a center of mass collision energy of 1.6 eV. H atoms were generated by 266 nm photolysis of HI in a mixture of HI and O2 at 293 K. The OH product was probed by laser induced fluorescence and the nascent OH vibrational, rotational, and fine structure distributions were determined. The OH(v=0/OH(v=1) vibrational branching ratio was measured to be 1.72 + or - 0.09. The data suggest that the H + O2 reaction at this collision energy proceeds via two competing mechanisms: reaction involving a long-lived complex and direct reaction.

  13. Characterization of a 5-eV neutral atomic oxygen beam facility

    NASA Technical Reports Server (NTRS)

    Vaughn, J. A.; Linton, R. C.; Carruth, M. R., Jr.; Whitaker, A. F.; Cuthbertson, J. W.; Langer, W. D.; Motley, R. W.

    1991-01-01

    An experimental effort to characterize an existing 5-eV neutral atomic oxygen beam facility being developed at Princeton Plasma Physics Laboratory is described. This characterization effort includes atomic oxygen flux and flux distribution measurements using a catalytic probe, energy determination using a commercially designed quadrupole mass spectrometer (QMS), and the exposure of oxygen-sensitive materials in this beam facility. Also, comparisons were drawn between the reaction efficiencies of materials exposed in plasma ashers, and the reaction efficiencies previously estimated from space flight experiments. The results of this study show that the beam facility is capable of producing a directional beam of neutral atomic oxygen atoms with the needed flux and energy to simulate low Earth orbit (LEO) conditions for real time accelerated testing. The flux distribution in this facility is uniform to +/- 6 percent of the peak flux over a beam diameter of 6 cm.

  14. Photodissociation of protonated leucine-enkephalin in the VUV range of 8-40 eV

    SciTech Connect

    Bari, S.; Gonzalez-Magana, O.; Reitsma, G.; Hoekstra, R.; Schlathoelter, T.; Werner, J.; Schippers, S.

    2011-01-14

    Until now, photodissociation studies on free complex protonated peptides were limited to the UV wavelength range accessible by intense lasers. We have studied photodissociation of gas-phase protonated leucine-enkephalin cations for vacuum ultraviolet (VUV) photons energies ranging from 8 to 40 eV. We report time-of-flight mass spectra of the photofragments and various photofragment-yields as a function of photon energy. For sub-ionization energies our results are in line with existing studies on UV photodissociation of leucine-enkephalin. For photon energies exceeding 10 eV we could identify a new dissociation scheme in which photoabsorption leads to a fast loss of the tyrosine side chain. This loss process leads to the formation of a residual peptide that is remarkably cold internally.

  15. Measurement of the depth of maximum of extensive air showers above 10{18} eV.

    PubMed

    Abraham, J; Abreu, P; Aglietta, M; Ahn, E J; Allard, D; Allekotte, I; Allen, J; Alvarez-Muñiz, J; Ambrosio, M; Anchordoqui, L; Andringa, S; Anticić, T; Anzalone, A; Aramo, C; Arganda, E; Arisaka, K; Arqueros, F; Asorey, H; Assis, P; Aublin, J; Ave, M; Avila, G; Bäcker, T; Badagnani, D; Balzer, M; Barber, K B; Barbosa, A F; Barroso, S L C; Baughman, B; Bauleo, P; Beatty, J J; Becker, B R; Becker, K H; Bellétoile, A; Bellido, J A; Benzvi, S; Berat, C; Bergmann, T; Bertou, X; Biermann, P L; Billoir, P; Blanch-Bigas, O; Blanco, F; Blanco, M; Bleve, C; Blümer, H; Bohácová, M; Boncioli, D; Bonifazi, C; Bonino, R; Borodai, N; Brack, J; Brogueira, P; Brown, W C; Bruijn, R; Buchholz, P; Bueno, A; Burton, R E; Busca, N G; Caballero-Mora, K S; Caramete, L; Caruso, R; Castellina, A; Catalano, O; Cataldi, G; Cazon, L; Cester, R; Chauvin, J; Chiavassa, A; Chinellato, J A; Chou, A; Chudoba, J; Clay, R W; Colombo, E; Coluccia, M R; Conceição, R; Contreras, F; Cook, H; Cooper, M J; Coppens, J; Cordier, A; Cotti, U; Coutu, S; Covault, C E; Creusot, A; Criss, A; Cronin, J; Curutiu, A; Dagoret-Campagne, S; Dallier, R; Daumiller, K; Dawson, B R; de Almeida, R M; De Domenico, M; De Donato, C; de Jong, S J; De La Vega, G; de Mello Junior, W J M; de Mello Neto, J R T; De Mitri, I; de Souza, V; de Vries, K D; Decerprit, G; Del Peral, L; Deligny, O; Della Selva, A; Delle Fratte, C; Dembinski, H; Di Giulio, C; Diaz, J C; Díaz Castro, M L; Diep, P N; Dobrigkeit, C; D'Olivo, J C; Dong, P N; Dorofeev, A; Dos Anjos, J C; Dova, M T; D'Urso, D; Dutan, I; Duvernois, M A; Ebr, J; Engel, R; Erdmann, M; Escobar, C O; Etchegoyen, A; Facal San Luis, P; Falcke, H; Farrar, G; Fauth, A C; Fazzini, N; Ferrero, A; Fick, B; Filevich, A; Filipcic, A; Fleck, I; Fliescher, S; Fracchiolla, C E; Fraenkel, E D; Fröhlich, U; Fulgione, W; Gamarra, R F; Gambetta, S; García, B; García Gámez, D; Garcia-Pinto, D; Garrido, X; Gelmini, G; Gemmeke, H; Ghia, P L; Giaccari, U; Giller, M; Glass, H; Goggin, L M; Gold, M S; Golup, G; Gomez Albarracin, F; Gómez Berisso, M; Gonçalves, P; Gonzalez, D; Gonzalez, J G; Góra, D; Gorgi, A; Gouffon, P; Gozzini, S R; Grashorn, E; Grebe, S; Grigat, M; Grillo, A F; Guardincerri, Y; Guarino, F; Guedes, G P; Hague, J D; Halenka, V; Hansen, P; Harari, D; Harmsma, S; Harton, J L; Haungs, A; Hebbeker, T; Heck, D; Herve, A E; Hojvat, C; Holmes, V C; Homola, P; Hörandel, J R; Horneffer, A; Hrabovský, M; Huege, T; Hussain, M; Iarlori, M; Insolia, A; Ionita, F; Italiano, A; Jiraskova, S; Kadija, K; Kaducak, M; Kampert, K H; Karova, T; Kasper, P; Kégl, B; Keilhauer, B; Keivani, A; Kelley, J; Kemp, E; Kieckhafer, R M; Klages, H O; Kleifges, M; Kleinfeller, J; Knapik, R; Knapp, J; Koang, D-H; Krieger, A; Krömer, O; Kruppke-Hansen, D; Kuehn, F; Kuempel, D; Kulbartz, K; Kunka, N; Kusenko, A; La Rosa, G; Lachaud, C; Lago, B L; Lautridou, P; Leão, M S A B; Lebrun, D; Lebrun, P; Lee, J; Leigui de Oliveira, M A; Lemiere, A; Letessier-Selvon, A; Lhenry-Yvon, I; López, R; Lopez Agüera, A; Louedec, K; Lozano Bahilo, J; Lucero, A; Ludwig, M; Lyberis, H; Maccarone, M C; Macolino, C; Maldera, S; Mandat, D; Mantsch, P; Mariazzi, A G; Marin, V; Maris, I C; Marquez Falcon, H R; Marsella, G; Martello, D; Martínez Bravo, O; Mathes, H J; Matthews, J; Matthews, J A J; Matthiae, G; Maurizio, D; Mazur, P O; McEwen, M; Medina-Tanco, G; Melissas, M; Melo, D; Menichetti, E; Menshikov, A; Meurer, C; Micanović, S; Micheletti, M I; Miller, W; Miramonti, L; Mollerach, S; Monasor, M; Monnier Ragaigne, D; Montanet, F; Morales, B; Morello, C; Moreno, E; Moreno, J C; Morris, C; Mostafá, M; Mueller, S; Muller, M A; Mussa, R; Navarra, G; Navarro, J L; Navas, S; Necesal, P; Nellen, L; Nhung, P T; Nierstenhoefer, N; Nitz, D; Nosek, D; Nozka, L; Nyklicek, M; Oehlschläger, J; Olinto, A; Oliva, P; Olmos-Gilbaja, V M; Ortiz, M; Pacheco, N; Pakk Selmi-Dei, D; Palatka, M; Pallotta, J; Palmieri, N; Parente, G; Parizot, E; Parlati, S; Parra, A; Parrisius, J; Parsons, R D; Pastor, S; Paul, T; Pavlidou, V; Payet, K; Pech, M; Pekala, J; Pelayo, R; Pepe, I M; Perrone, L; Pesce, R; Petermann, E; Petrera, S; Petrinca, P; Petrolini, A; Petrov, Y; Petrovic, J; Pfendner, C; Piegaia, R; Pierog, T; Pimenta, M; Pirronello, V; Platino, M; Ponce, V H; Pontz, M; Privitera, P; Prouza, M; Quel, E J; Rautenberg, J; Ravel, O; Ravignani, D; Redondo, A; Revenu, B; Rezende, F A S; Ridky, J; Riggi, S; Risse, M; Ristori, P; Rivière, C; Rizi, V; Robledo, C; Rodriguez, G; Rodriguez Martino, J; Rodriguez Rojo, J; Rodriguez-Cabo, I; Rodríguez-Frías, M D; Ros, G; Rosado, J; Rossler, T; Roth, M; Rouillé-d'Orfeuil, B; Roulet, E; Rovero, A C; Salamida, F; Salazar, H; Salina, G; Sánchez, F; Santander, M; Santo, C E; Santos, E; Santos, E M; Sarazin, F; Sarkar, S; Sato, R; Scharf, N; Scherini, V; Schieler, H; Schiffer, P; Schmidt, A; Schmidt, F; Schmidt, T; Scholten, O; Schoorlemmer, H; Schovancova, J; Schovánek, P; Schroeder, F; Schulte, S; Schüssler, F; Schuster, D; Sciutto, S J; Scuderi, M; Segreto, A; Semikoz, D; Settimo, M; Shadkam, A; Shellard, R C; Sidelnik, I; Siffert, B B; Sigl, G; Smiałkowski, A; Smída, R; Snow, G R; Sommers, P; Sorokin, J; Spinka, H; Squartini, R; Stasielak, J; Stephan, M; Strazzeri, E; Stutz, A; Suarez, F; Suomijärvi, T; Supanitsky, A D; Susa, T; Sutherland, M S; Swain, J; Szadkowski, Z; Tamashiro, A; Tamburro, A; Tapia, A; Tarutina, T; Taşcău, O; Tcaciuc, R; Tcherniakhovski, D; Tegolo, D; Thao, N T; Thomas, D; Tiffenberg, J; Timmermans, C; Tkaczyk, W; Todero Peixoto, C J; Tomé, B; Tonachini, A; Travnicek, P; Tridapalli, D B; Tristram, G; Trovato, E; Tueros, M; Ulrich, R; Unger, M; Urban, M; Valdés Galicia, J F; Valiño, I; Valore, L; van den Berg, A M; Vázquez, J R; Vázquez, R A; Veberic, D; Venters, T; Verzi, V; Videla, M; Villaseñor, L; Vorobiov, S; Voyvodic, L; Wahlberg, H; Wahrlich, P; Wainberg, O; Warner, D; Watson, A A; Westerhoff, S; Whelan, B J; Wieczorek, G; Wiencke, L; Wilczyńska, B; Wilczyński, H; Williams, C; Winchen, T; Winnick, M G; Wundheiler, B; Yamamoto, T; Younk, P; Yuan, G; Yushkov, A; Zas, E; Zavrtanik, D; Zavrtanik, M; Zaw, I; Zepeda, A; Ziolkowski, M

    2010-03-01

    We describe the measurement of the depth of maximum, X{max}, of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 10;{18} eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106{-21}{+35}) g/cm{2}/decade below 10{18.24+/-0.05} eV, and (24+/-3) g/cm{2}/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm{2}. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed. PMID:20366976

  16. VUV action spectroscopy of protonated leucine-enkephalin peptide in the 6-14 eV range

    DOE PAGESBeta

    Ranković, M. Lj.; Canon, F.; Nahon, L.; Giuliani, A.; Milosavljević, A. R.

    2015-12-29

    We have studied the VUV photodissociation of gas-phase protonated leucine-enkephalin peptide ion in the 5.7 to 14 eV photon energy range by coupling a linear quadrupole ion trap with a synchrotron radiation source. We report VUV activation tandem mass spectra at 6.7, 8.4 and 12.8 eV photon energies and photodissociation yields for a number of selected fragments. The obtained results provide insights into both near VUV radiation damage and electronic properties of a model peptide. We could distinguish several absorption bands and assign them to particular electronic transitions, according to previous theoretical studies. Furthermore, the photodissociation yields appear to bemore » very different for the various observed fragmentation channels, depending both on the type of fragments and their position along the peptide backbone. The present results are discussed in light of recent gas-phase spectroscopic data on peptides.« less

  17. VUV action spectroscopy of protonated leucine-enkephalin peptide in the 6-14 eV range

    SciTech Connect

    Ranković, M. Lj.; Canon, F.; Nahon, L.; Giuliani, A.; Milosavljević, A. R.

    2015-12-29

    We have studied the VUV photodissociation of gas-phase protonated leucine-enkephalin peptide ion in the 5.7 to 14 eV photon energy range by coupling a linear quadrupole ion trap with a synchrotron radiation source. We report VUV activation tandem mass spectra at 6.7, 8.4 and 12.8 eV photon energies and photodissociation yields for a number of selected fragments. The obtained results provide insights into both near VUV radiation damage and electronic properties of a model peptide. We could distinguish several absorption bands and assign them to particular electronic transitions, according to previous theoretical studies. Furthermore, the photodissociation yields appear to be very different for the various observed fragmentation channels, depending both on the type of fragments and their position along the peptide backbone. The present results are discussed in light of recent gas-phase spectroscopic data on peptides.

  18. VUV action spectroscopy of protonated leucine-enkephalin peptide in the 6-14 eV range

    SciTech Connect

    Ranković, M. Lj.; Canon, F.; Nahon, L.; Giuliani, A.; Milosavljević, A. R.

    2015-12-28

    We have studied the Vacuum Ultraviolet (VUV) photodissociation of gas-phase protonated leucine-enkephalin peptide ion in the 5.7 to 14 eV photon energy range by coupling a linear quadrupole ion trap with a synchrotron radiation source. We report VUV activation tandem mass spectra at 6.7, 8.4, and 12.8 eV photon energies and photodissociation yields for a number of selected fragments. The obtained results provide insight into both near VUV radiation damage and electronic properties of a model peptide. We could distinguish several absorption bands and assign them to particular electronic transitions, according to previous theoretical studies. The photodissociation yields appear to be very different for the various observed fragmentation channels, depending on both the types of fragments and their position along the peptide backbone. The present results are discussed in light of recent gas-phase spectroscopic data on peptides.

  19. Measurement of the Depth of Maximum of Extensive Air Showers above 10^18 eV

    SciTech Connect

    Abraham, J.; Abreu, P.; Aglietta, M.; Ahn, E.J.; Allard, D.; Allekotte, I.; Allen, J.; Alvarez-Muniz, J.; Ambrosio, M.; Anchordoqui, L.; Andringa, S.; /Lisbon, IST /Boskovic Inst., Zagreb

    2010-02-01

    We describe the measurement of the depth of maximum, X{sub max}, of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 10{sup 18} eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106{sub -21}{sup +35}) g/cm{sup 2}/decade below 10{sup 18.24 {+-} 0.05}eV, and (24 {+-} 3) g/cm{sup 2}/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm{sup 2}. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed.

  20. An Instrument to Measure Elemental Energy Spectra of Cosmic Ray Nuclei Up to 10(exp 16) eV

    NASA Technical Reports Server (NTRS)

    Adams, J.; Bashindzhagyan, G.; Chilingarian, A.; Drury, L.; Egorov, N.; Golubkov,S.; Korotkova, N.; Panasyuk, M.; Podorozhnyi, D.; Procqureur, J.

    2000-01-01

    A longstanding goal of cosmic ray research is to measure the elemental energy spectra of cosmic rays up to and through the "knee" (approx. equal to 3 x 10 (exp 15) eV. It is not currently feasible to achieve this goal with an ionization calorimeter because the mass required to be deployed in Earth orbit is very large (at least 50 tonnes). An alternative method will be presented. This is based on measuring the primary particle energy by determining the angular distribution of secondaries produced in a target layer using silicon microstrip detector technology. The proposed technique can be used over a wide range of energies (10 (exp 11)- 10 (exp 16) eV) and gives an energy resolution of 60% or better. Based on this technique, a design for a new lightweight instrument with a large aperture (KLEM) will be described.

  1. A platform for actively loading cargo RNA to elucidate limiting steps in EV-mediated delivery

    PubMed Central

    Hung, Michelle E.; Leonard, Joshua N.

    2016-01-01

    Extracellular vesicles (EVs) mediate intercellular communication through transfer of RNA and protein between cells. Thus, understanding how cargo molecules are loaded and delivered by EVs is of central importance for elucidating the biological roles of EVs and developing EV-based therapeutics. While some motifs modulating the loading of biomolecular cargo into EVs have been elucidated, the general rules governing cargo loading and delivery remain poorly understood. To investigate how general biophysical properties impact loading and delivery of RNA by EVs, we developed a platform for actively loading engineered cargo RNAs into EVs. In our system, the MS2 bacteriophage coat protein was fused to EV-associated proteins, and the cognate MS2 stem loop was engineered into cargo RNAs. Using this Targeted and Modular EV Loading (TAMEL) approach, we identified a configuration that substantially enhanced cargo RNA loading (up to 6-fold) into EVs. When applied to vesicles expressing the vesicular stomatitis virus glycoprotein (VSVG) – gesicles – we observed a 40-fold enrichment in cargo RNA loading. While active loading of mRNA-length (>1.5 kb) cargo molecules was possible, active loading was much more efficient for smaller (~0.5 kb) RNA molecules. We next leveraged the TAMEL platform to elucidate the limiting steps in EV-mediated delivery of mRNA and protein to prostate cancer cells, as a model system. Overall, most cargo was rapidly degraded in recipient cells, despite high EV-loading efficiencies and substantial EV uptake by recipient cells. While gesicles were efficiently internalized via a VSVG-mediated mechanism, most cargo molecules were rapidly degraded. Thus, in this model system, inefficient endosomal fusion or escape likely represents a limiting barrier to EV-mediated transfer. Altogether, the TAMEL platform enabled a comparative analysis elucidating a key opportunity for enhancing EV-mediated delivery to prostate cancer cells, and this technology should be of

  2. Gravity, body mass and composition, and metabolic rate

    NASA Technical Reports Server (NTRS)

    Pace, N.; Smith, A. H.

    1984-01-01

    The scale effects of increased gravitational loading by chronic centrifugation on metabolic rate and body composition in metabolically mature mammals were investigated. Individual oxygen consumption rates in groups of 12 each, 8-month-old, hamster, rats, guinea pigs, and rabbits were measured at weekly intervals at 1.0 g, then 2.0 g for 6 weeks. Metabolic rate was increased significantly in all species, and stabilized after 2 weeks at 2.0 g. Statistical analysis of the data revealed that the larger the animal the greater was the increase in mass-specific metabolic rate, or metabolic intensity, over the 1.0 g value for the same animal, with the result that the interspecies allometric scaling relationship between metabolic rate and total body mass is different at 2.0 g compared 10 1.0 g. Analysis of covariance shows that the postioning constant at 2.0 g is increased by 17% at 2.0 g at the P .001 level, and the exponent is increased by 8% at the P = 0.008 level. Thus, the hypothesis that augmented gravitational loading should shift the allometric relationship between metabolic rate and body size by an increase in both parameters is supported.

  3. Synchrotron based mass spectrometry to investigate the molecular properties of mineral-organic associations

    SciTech Connect

    Liu, Suet Yi; Kleber, Markus; Takahashi, Lynelle K.; Nico, Peter; Keiluweit, Marco; Ahmed, Musahid

    2013-04-01

    Soil organic matter (OM) is important because its decay drives life processes in the biosphere. Analysis of organic compounds in geological systems is difficult because of their intimate association with mineral surfaces. To date there is no procedure capable of quantitatively separating organic from mineral phases without creating artifacts or mass loss. Therefore, analytical techniques that can (a) generate information about both organic and mineral phases simultaneously and (b) allow the examination of predetermined high-interest regions of the sample as opposed to conventional bulk analytical techniques are valuable. Laser Desorption Synchrotron Postionization (synchrotron-LDPI) mass spectrometry is introduced as a novel analytical tool to characterize the molecular properties of organic compounds in mineral-organic samples from terrestrial systems, and it is demonstrated that when combined with Secondary Ion Mass Spectrometry (SIMS), can provide complementary information on mineral composition. Mass spectrometry along a decomposition gradient in density fractions, verifies the consistency of our results with bulk analytical techniques. We further demonstrate that by changing laser and photoionization energies, variations in molecular stability of organic compounds associated with mineral surfaces can be determined. The combination of synchrotron-LDPI and SIMS shows that the energetic conditions involved in desorption and ionization of organic matter may be a greater determinant of mass spectral signatures than the inherent molecular structure of the organic compounds investigated. The latter has implications for molecular models of natural organic matter that are based on mass spectrometric information.

  4. Electron and Positron Scattering from Chlorine Molecules in the Energy Region from 0.8 ev to 600 eV

    NASA Astrophysics Data System (ADS)

    Kimura, Mineo

    2002-10-01

    ELECTRON AND POSITRON SCATTERING FROM CHLORINE MOLECULES IN THE ENERGY REGION FROM 0.8 eV TO 600 eV C. Makochekanwa, H. Kawate, O. Sueoka and M. Kimura Graduate School of Science and Engineering, Yamaguchi University, Ube, Yamaguchi 755-8611, Japan Total scattering cross sections for chlorine molecules by electron impact are determined experimentally for the impact energies from 0.8 eV to 600 eV. Elastic scattering cross sections are also determined theoretically. The results above 23 eV are the first report on these processes. The present results are in good accord in the energy-dependence with the previous measurements, although the absolute magnitude is found to be about 30% smaller than that of Gulley et al. [J. Phys. B31, 2971 (1998)]. Strong sharp peaks around 7.8 eV and 12 eV are observed and well separated, and the one at 7.8 eV is attributed to dissociative electron attachment, while the one at 12 eV is speculated to be due to ion-pair formation through direct dissociation. The present elastic cross sections are found to show the similar shape to the TCS although the magnitude is smaller by a few % below 30 eV to a factor of two at 100 eV. Small-scale experimental study is also carried out for determining total and positronium formation cross sections by positron impact as well to carry out the comparative study.

  5. Direct measurements of neutrino mass

    SciTech Connect

    Robertson, R.G.H.

    1991-01-01

    Some recent developments in the experimental search for neutrino mass are discussed. New data from Los Alamos on the electron neutrino mass as measured in tritium beta decay give an upper limit of 9.3 eV at the 95% confidence level. This result is not consistent with the long-standing ITEP result of 26(5) eV within a model-independent'' range of 17 to 40 eV. It now appears that the electron neutrino is not sufficiently massive to close the universe by itself. Hime and Jelley report finding new evidence for a 17-keV neutrino in the {Beta} decay of {sup 35}S and {sup 63}Ni. Many other experiments are being reported and the situation is still unresolved. 56 refs., 1 fig., 3 tabs.

  6. A Novel Recombinant Enterovirus Type EV-A89 with Low Epidemic Strength in Xinjiang, China

    PubMed Central

    Fan, Qin; Zhang, Yong; Hu, Lan; Sun, Qiang; Cui, Hui; Yan, Dongmei; Sikandaner, Huerxidan; Tang, Haishu; Wang, Dongyan; Zhu, Zhen; Zhu, Shuangli; Xu, Wenbo

    2015-01-01

    Enterovirus A89 (EV-A89) is a novel member of the EV-A species. To date, only one full-length genome sequence (the prototype strain) has been published. Here, we report the molecular identification and genomic characterization of a Chinese EV-A89 strain, KSYPH-TRMH22F/XJ/CHN/2011, isolated in 2011 from a contact of an acute flaccid paralysis (AFP) patient during AFP case surveillance in Xinjiang China. This was the first report of EV-A89 in China. The VP1 coding sequence of this strain demonstrated 93.2% nucleotide and 99.3% amino acid identity with the EV-A89 prototype strain. In the P2 and P3 regions, the Chinese EV-A89 strain demonstrated markedly higher identity than the prototype strains of EV-A76, EV-A90, and EV-A91, indicating that one or more recombination events between EV-A89 and these EV-A types might have occurred. Long-term evolution of these EV types originated from the same ancestor provides the spatial and temporal circumstances for recombination to occur. An antibody sero-prevalence survey against EV-A89 in two Xinjiang prefectures demonstrated low positive rates and low titres of EV-A89 neutralization antibody, suggesting limited range of transmission and exposure to the population. This study provides a solid foundation for further studies on the biological and pathogenic properties of EV-A89. PMID:26685900

  7. The Periodicity Analysis of Semiregular Variable Star EV Aquarii

    NASA Astrophysics Data System (ADS)

    Terziev, E.; Percy, J. R.; Henden, A. A.

    2011-10-01

    EV Aquarii is a variable star which was formerly misclassified as a cataclysmic variable, but photometric observations and colour indices have since indicated that it is most likely a semiregular M giant. The authors of this paper have used self-correlation analysis and Fourier analysis to determine the variability profile of the star. Data from the AAVSO International Database, the All-Sky Automated Survey, The Amateur Sky Survey, and co-author Arne Henden were used. The period of variation has been found to be 123.6 days ± 2.1 days. The amplitude of this variation is not constant; it changes with time between approximately 0.4 and 1.0 magnitude. There were no indications of a longer secondary period, though there has been observed an instance of a transient period of variation on a shorter timescale of about 40 days. There was no evidence found of periodic variation of the color differences.

  8. Recent Progress towards Novel EV71 Anti-Therapeutics and Vaccines.

    PubMed

    Ng, Qingyong; He, Fang; Kwang, Jimmy

    2015-12-01

    Enterovirus 71 (EV71) is a group of viruses that belongs to the Picornaviridae family, which also includes viruses such as polioviruses. EV71, together with coxsackieviruses, is widely known for its association with Hand Foot Mouth Disease (HFMD), which generally affects children age five and below. Besides HFMD, EV71 can also trigger more severe and life-threatening neurological conditions such as encephalitis. Considering the lack of a vaccine and antiviral drug against EV71, together with the increasing spread of these viruses, the development of such drugs and vaccines becomes the top priority in protecting our younger generations. This article, hence, reviews some of the recent progress in the formulations of anti-therapeutics and vaccine generation for EV71, covering (i) inactivated vaccines; (ii) baculovirus-expressed vaccines against EV71; (iii) human intravenous immunoglobulin (IVIg) treatment; and (iv) the use of monoclonal antibody therapy as a prevention and treatment for EV71 infections. PMID:26670245

  9. Recent Progress towards Novel EV71 Anti-Therapeutics and Vaccines

    PubMed Central

    Ng, Qingyong; He, Fang; Kwang, Jimmy

    2015-01-01

    Enterovirus 71 (EV71) is a group of viruses that belongs to the Picornaviridae family, which also includes viruses such as polioviruses. EV71, together with coxsackieviruses, is widely known for its association with Hand Foot Mouth Disease (HFMD), which generally affects children age five and below. Besides HFMD, EV71 can also trigger more severe and life-threatening neurological conditions such as encephalitis. Considering the lack of a vaccine and antiviral drug against EV71, together with the increasing spread of these viruses, the development of such drugs and vaccines becomes the top priority in protecting our younger generations. This article, hence, reviews some of the recent progress in the formulations of anti-therapeutics and vaccine generation for EV71, covering (i) inactivated vaccines; (ii) baculovirus-expressed vaccines against EV71; (iii) human intravenous immunoglobulin (IVIg) treatment; and (iv) the use of monoclonal antibody therapy as a prevention and treatment for EV71 infections. PMID:26670245

  10. Microfluidic Chip Coupled with Thermal Desorption Atmospheric Pressure Ionization Mass Spectrometry

    PubMed Central

    Chang, Chia-Hsien; Chen, Tsung-Yi; Chen, Yu-Chie

    2014-01-01

    Microfluidic chips have been used as platforms for a diversity of research purposes such as for separation and micro-reaction. One of the suitable detectors for microfluidic chip is mass spectrometry. Because microfluidic chips are generally operated in an open air condition, mass spectrometry coupled with atmospheric pressure ion sources can suit the requirement with minimum compromise. In this study, we develop a new interface to couple a microfluidic chip with mass spectrometry. A capillary tip coated with a layer of graphite, capable of absorbing energy of near-infrared (NIR) light is used to interface microfluidic chip with mass spectrometry. An NIR laser diode (λ=808 nm) is used to irradiate the capillary tip for assisting the generation of spray from the eluent of the microfluidic chip. An electrospray is provided to fuse with the spray generated from the microfluidic chip for post-ionization. Transesterification is used as the example to demonstrate the feasibility of using this interface to couple microfluidic chip with mass spectrometry. PMID:26839753

  11. Mass determination of neutrinos

    NASA Technical Reports Server (NTRS)

    Chiu, Hong-Yee

    1988-01-01

    A time-energy correlation method has been developed to determine the signature of a nonzero neutrino mass in a small sample of neutrinos detected from a distant source. The method is applied to the Kamiokande II (Hirata et al., 1987) and IMB (Bionta et al., 1987) observations of neutrino bursts from SN 1987A. Using the Kamiokande II data, the neutrino rest mass is estimated at 2.8 + 2.0, - 1.4 eV and the initial neutrino pulse is found to be less than 0.3 sec full width, followed by an emission tail lasting at least 10 sec.

  12. Experimental search for solar hidden photons in the eV energy range using kinetic mixing with photons

    SciTech Connect

    Mizumoto, T.; Ohta, R.; Horie, T.; Suzuki, J.; Minowa, M.; Inoue, Y. E-mail: comic@icepp.s.u-tokyo.ac.jp E-mail: jsuzuki@icepp.s.u-tokyo.ac.jp E-mail: minowa@phys.s.u-tokyo.ac.jp

    2013-07-01

    We have searched for solar hidden photons in the eV energy range using a dedicated hidden photon detector. The detector consisted of a parabolic mirror with a diameter of 500 mm and a focal length of 1007 mm installed in a vacuum chamber, and a photomultiplier tube at its focal point. The detector was attached to the Tokyo axion helioscope, Sumico which has a mechanism to track the sun. From the result of the measurement, we found no evidence for the existence of hidden photons and set a limit on the photon-hidden photon mixing parameter χ depending on the hidden photon mass m{sub γ'}.

  13. Dynamics of H+ + CO at ELab = 30 eV

    NASA Astrophysics Data System (ADS)

    Stopera, Christopher; Maiti, Buddhadev; Grimes, Thomas V.; McLaurin, Patrick M.; Morales, Jorge A.

    2012-02-01

    The astrophysically relevant system H+ + CO (vi = 0) → H+ + CO (vf) at ELab = 30 eV is studied with the simplest-level electron nuclear dynamics (SLEND) method. This investigation follows previous successful SLEND studies of H+ + H2 and H+ + N2 at ELab = 30 eV [J. Morales, A. Diz, E. Deumens, and Y. Öhrn, J. Chem. Phys. 103(23), 9968 (1995), 10.1063/1.469886; C. Stopera, B. Maiti, T. V. Grimes, P. M. McLaurin, and J. A. Morales, J. Chem. Phys. 134(22), 224308 (2011), 10.1063/1.3598511]. SLEND is a direct, time-dependent, variational, and non-adiabatic method that adopts a classical-mechanics description for the nuclei and a single-determinantal wavefunction for the electrons. A canonical coherent-states (CS) procedure associated with SLEND reconstructs quantum vibrational properties from the SLEND classical dynamics. Present SLEND results include reactivity predictions, snapshots of the electron density evolution, average vibrational energy transfers, rainbow angle predictions, total and vibrationally resolved differential cross sections (DCS), and average vibrational excitation probabilities. SLEND results are compared with available data from experiments and vibrational close-coupling rotational infinite-order sudden (VCC-RIOS) approximation calculations. Present simulations employ four basis sets: STO-3G, 6-31G, 6-31G**, and cc-pVDZ to determine their effect on the results. SLEND simulations predict non-charge-transfer scattering and CO collision-induced dissociation as the main reactions. SLEND/6-31G, /6-31G**, and /cc-pVDZ predict rainbow angles and total DCS in excellent agreement with experiments and more accurate than their VCC-RIOS counterparts. SLEND/6-31G** and /cc-pVDZ predict vibrationally resolved DCS for vf = 0-2 in satisfactory experimental agreement, but less accurate than their comparable H+ + CO VCC-RIOS and H+ + H2 and H+ + N2 SLEND results. SLEND/6-31G** and /cc-pVDZ predict qualitatively correct average vibrational excitation probabilities

  14. High intensity 5 eV atomic oxygen source and Low Earth Orbit (LEO) simulation facility

    NASA Technical Reports Server (NTRS)

    Cross, J. B.; Spangler, L. H.; Hoffbauer, M. A.; Archuleta, F. A.; Leger, Lubert; Visentine, James

    1987-01-01

    An atomic oxygen exposure facility has been developed for studies of material degradation. The goal of these studies is to provide design criteria and information for the manufacture of long life (20 to 30 years) construction materials for use in LEO. The studies that are being undertaken using the facility will provide: absolute reaction cross sections for use in engineering design problems; formulations of reaction mechanisms; and calibration of flight hardware (mass spectrometers, etc.) in order to directly relate experiments performed in LEO to ground based investigations. The facility consists of: (1) a CW laser sustained discharge source of O atoms having a variable energy up to 5 eV and an intensity between 10(15) and 10(17) O atoms s(-1) cm(-2); (2) an atomic beam formation and diagnostics system consisting of various stages of differential pumping, a mass spectrometer detector, and a time of flight analyzer; (3) a spinning rotor viscometer for absolute O atom flux measurements; and (4) provision for using the system for calibration of actual flight instruments. Surface analysis equipment is available for the characterization of material surfaces before and after exposure to O atoms.

  15. Determinants of EV71 immunogenicity and protection against lethal challenge in a mouse model.

    PubMed

    Chang, Junliang; Li, Jingliang; Wei, Wei; Liu, Xin; Liu, Guanchen; Yang, Jiaxin; Zhang, Wenyan; Yu, Xiao-Fang

    2015-07-01

    Circulating enterovirus 71 (EV71)-associated hand, foot, and mouth disease (HFMD) is a major public health problem in the Asian-Pacific region. An EV71 vaccine for HFMD prevention is currently being developed. However, viral determinants that could influence the vaccine's efficacy have not been well characterized. In this study, we isolated and characterized several EV71 strains that are currently circulating in northern and southern China. We determined that VP1 variation is a major determinant of EV71 immunogenicity. A single amino acid variation in VP1 can lead to significant differences in the breadth and potency of immune responses against primary EV71 isolates as well as the sensitivity of EV71 to heterologous neutralizing antibody responses. We also identified EV71 strains that could induce potent immunogenic and cross-neutralizing antibody responses against diverse EV71 strains. Furthermore, these neutralizing antibodies could protect neonatal mice from lethal dose challenge with various circulating EV71 viruses. Our study provides useful information for EV71 vaccine development and evaluation. PMID:26025091

  16. Baseline Testing of The EV Global E-Bike

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.; Kolacz, John S.; Tavernelli, Paul F.

    2001-01-01

    The NASA John H. Glenn Research Center initiated baseline testing of the EV Global E-Bike as a way to reduce pollution in urban areas, reduce fossil fuel consumption and reduce Operating costs for transportation systems. The work was done Linder the Hybrid Power Management (HPM) Program, which includes the Hybrid Electric Transit Bus (HETB). The E-Bike is a state of the art, ground up, hybrid electric bicycle. Unique features of the vehicle's power system include the use of an efficient, 400 W. electric hub motor and a 7-speed derailleur system that permits operation as fully electric, fully pedal, or a combination of the two. Other innovative features, such as regenerative braking through ultracapacitor energy storage are planned. Regenerative braking recovers much of the kinetic energy of the vehicle during deceleration. The E-Bike is an inexpensive approach to advance the state of the art in hybrid technology in a practical application. The project transfers space technology to terrestrial use via nontraditional partners, and provides power system data valuable for future space applications. A description of the E-bike, the results of performance testing, and future vehicle development plans is the subject of this report. The report concludes that the E-Bike provides excellent performance, and that the implementation of ultracapacitors in the power system can provide significant performance improvements.

  17. Baseline Testing of the EV Global E-Bike SX

    NASA Technical Reports Server (NTRS)

    Eichenherg, Dennis J.; Kolacz, John S.; Tavernelli, Paul F.

    2001-01-01

    The NASA John H. Glenn Research Center initiated baseline testing of the EV Global E-Bike SX as an update of the state of the art in hybrid electric bicycles. The E-bike is seen as a way to reduce pollution in urban areas, reduce fossil fuel consumption, and reduce operating costs for transportation systems. The work was done under the Hybrid Power Management (HPM) Program, which includes the Hybrid Electric Transit Bus (HETB). The SX is a high performance, state of the art, ground up, hybrid electric bicycle. Unique features of the SX's 36 V power system include the use of an efficient, 400 W, electric hub motor, and a seven-speed derailleur system that permits operation as fully electric, fully pedal, or a combination of the two. Other innovative features, such as regenerative braking through ultracapacitor energy storage, are planned. Regenerative braking recovers much of the kinetic energy of the vehicle during deceleration. The E-Bike is an inexpensive approach to advance the state of the art in hybrid technology in a practical application. The project transfers space technology to terrestrial use via nontraditional partners, and provides power system data valuable for future space applications. A description of the SX, the results of performance testing, and future vehicle development plans are given in this report. The report concludes that the SX provides excellent performance, and that the implementation of ultracapacitors in the power system can provide significant performance improvements.

  18. Ratio method of measuring W boson mass

    SciTech Connect

    Guo, Feng

    2010-08-01

    This dissertation describes an alternative method of measuring the W boson mass in DØ experiment. Instead of extracting MW from the fitting of W → ev fast Monte Carlo simulations to W → ev data as in the standard method, we make the direct fit of transverse mass between W → ev data and Z → ee data. One of the two electrons from Z boson is treated as a neutrino in the calculation of transverse mass. In ratio method, the best fitted scale factor corresponds to the ratio of W and Z boson mass (MW/MZ). Given the precisely measured Z boson mass, W mass is directly fitted from W → ev and Z → ee data. This dissertation demonstrates that ratio method is a plausible method of measuring the W boson mass. With the 1 fb-1 DØ Run IIa dataset, ratio method gives MW = 80435 ± 43(stat) ± 26(sys) MeV.

  19. Design and performance of an instrument for electron impact tandem mass spectrometry and action spectroscopy of mass/charge selected macromolecular ions stored in RF ion trap*

    NASA Astrophysics Data System (ADS)

    Ranković, Milos Lj.; Giuliani, Alexandre; Milosavljević, Aleksandar R.

    2016-06-01

    A new apparatus was designed, coupling an electron gun with a linear quadrupole ion trap mass spectrometer, to perform m/ z (mass over charge) selected ion activation by electron impact for tandem mass spectrometry and action spectroscopy. We present in detail electron tracing simulations of a 300 eV electron beam inside the ion trap, design of the mechanical parts, electron optics and electronic circuits used in the experiment. We also report examples of electron impact activation tandem mass spectra for Ubiquitin protein, Substance P and Melittin peptides, at incident electron energies in the range from 280 eV to 300 eV.

  20. Spectra of protons and nuclei in the energy range of 1010 ÷ 1020 eV in the framework of Galactic cosmic ray origin

    NASA Astrophysics Data System (ADS)

    Volkov, Nikolay; Lagutin, Anatoly; Tyumentsev, Alexander; Raikin, Roman

    2015-08-01

    We consider the problem of the cosmic ray spectrum formation assuming that cosmic rays are produced by Galactic sources. The anomalous diffusion equation proposed in our recent papers is used to describe cosmic ray propagation in the interstellar medium. We show that in the framework of this approach and with generation spectrum exponent γ = 2.85 it is possible to reproduce locally observed basic features of cosmic rays in the energy region of 1010 ÷ 1020 eV: difference between spectral exponents of protons and other nuclei, mass composition variation, “knee” problem, flattening of the primary spectrum at E ≥ 1018 ÷ 1019 eV. The crucial model predictions for the mass composition behaviour in the ultra-high energy region are discussed.

  1. Direct Search for Low Mass Dark Matter Particles with CCDs

    DOE PAGESBeta

    Barreto, J.; Cease, H.; Diehl, H. T.; Estrada, J.; Flaugher, B.; Harrison, N.; Jones, J.; Kilminster, B.; Molina, J.; Smith, J.; et al

    2012-05-15

    A direct dark matter search is performed using fully-depleted high-resistivity CCD detectors. Due to their low electronic readout noise (RMS ~7 eV) these devices operate with a very low detection threshold of 40 eV, making the search for dark matter particles with low masses (~5 GeV) possible. The results of an engineering run performed in a shallow underground site are presented, demonstrating the potential of this technology in the low mass region.

  2. EV13 Genesis Reentry Observations and Data Analysis

    NASA Technical Reports Server (NTRS)

    Swift, Wesley R.; Suggs, Robert M.

    2006-01-01

    The Genesis spacecraft reentry represented a unique opportunity to observe a "calibrated meteor" from northern Nevada. Knowing its speed, mass, composition, and precise trajectory made it a good subject to test some of the algorithms used to determine meteoroid mass from observed brightness. It was also a good test of an inexpensive set of cameras which could be deployed to observe future shuttle reentries. The utility of consumer grade video cameras was evident during the STS-107 accident investigation and the Genesis reentry gave us the opportunity to specify and test commercially available cameras which could be used during future reentries. This report describes the video observations and their analysis, compares the results with a simple photometric model, describes the forward scatter radar experiment, and lists lessons learned from the expedition and implications for the Stardust reentry in January 2006 as well as future shuttle reentries.

  3. Driving and Charging Behavior of Nissan Leafs in The EV Project with Access to Workplace Charging

    SciTech Connect

    Don Scoffield; Shawn Salisbury; John Smart

    2014-11-01

    This paper documents findings from analysis of data collected from Nissan Leafs enrolled in The EV Project who parked and charged at workplaces with EV charging equipment. It will be published as a white paper on INL's website, accessible by the general public.

  4. Workplace Charging Behavior of Nissan Leafs in The EV Project at Six Work Sites

    SciTech Connect

    David Rohrbaugh; John Smart

    2014-11-01

    This paper documents findings from analysis of data collected from Nissan Leafs enrolled in The EV Project who parked and charged at six workplaces with EV charging equipment. It will be published as a white paper on INL's website, accessible by the general public.

  5. Comparison of the LEGO Mindstorms NXT and EV3 Robotics Education Platforms

    ERIC Educational Resources Information Center

    Sherrard, Ann; Rhodes, Amy

    2014-01-01

    The release of the latest LEGO Mindstorms EV3 robotics platform in September 2013 has provided a dilemma for many youth robotics leaders. There is a need to understand the differences in the Mindstorms NXT and EV3 in order to make future robotics purchases. In this article the differences are identified regarding software, hardware, sensors, the…

  6. 77 FR 51983 - Availability of Department of Energy EV Everywhere Grand Challenge Initial Framing Document and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-28

    .... SUMMARY: The EV Everywhere Grand Challenge is a U.S. Department of Energy ``Clean Energy Grand Challenge... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Availability of Department of Energy EV Everywhere...

  7. Immunogenicity Studies of Bivalent Inactivated Virions of EV71/CVA16 Formulated with Submicron Emulsion Systems

    PubMed Central

    Lin, Chih-Wei; Lu, Tsung-Chun; Chow, Yen-Hung; Huang, Ming-Hsi

    2014-01-01

    We assessed two strategies for preparing candidate vaccines against hand, foot, and mouth disease (HFMD) caused mainly by infections of enterovirus (EV) 71 and coxsackievirus (CV) A16. We firstly design and optimize the potency of adjuvant combinations of emulsion-based delivery systems, using EV71 candidate vaccine as a model. We then perform immunogenicity studies in mice of EV71/CVA16 antigen combinations formulated with PELC/CpG. A single dose of inactivated EV71 virion (0.2 μg) emulsified in submicron particles was found (i) to induce potent antigen-specific neutralizing antibody responses and (ii) consistently to elicit broad antibody responses against EV71 neutralization epitopes. A single dose immunogenicity study of bivalent activated EV71/CVA16 virion formulated with either Alum or PELC/CpG adjuvant showed that CVA16 antigen failed to elicit CVA16 neutralizing antibody responses and did not affect EV71-specific neutralizing antibody responses. A boosting dose of emulsified EV71/CVA16 bivalent vaccine candidate was found to be necessary to achieve high seroconversion of CVA16-specific neutralizing antibody responses. The current results are important for the design and development of prophylactic vaccines against HFMD and other emerging infectious diseases. PMID:25006583

  8. Catalytic Assessment: Understanding How MCQs and EVS Can Foster Deep Learning

    ERIC Educational Resources Information Center

    Draper, Stephen W.

    2009-01-01

    One technology for education whose adoption is currently expanding rapidly in UK higher education is that of electronic voting systems (EVS). As with all educational technology, whether learning benefits are achieved depends not on the technology but on whether an improved teaching method is introduced with it. EVS inherently relies on the…

  9. Comparative Analysis of Technologies for Quantifying Extracellular Vesicles (EVs) in Clinical Cerebrospinal Fluids (CSF)

    PubMed Central

    Akers, Johnny C.; Ramakrishnan, Valya; Nolan, John P.; Duggan, Erika; Fu, Chia-Chun; Hochberg, Fred H.; Chen, Clark C.; Carter, Bob S.

    2016-01-01

    Extracellular vesicles (EVs) have emerged as a promising biomarker platform for glioblastoma patients. However, the optimal method for quantitative assessment of EVs in clinical bio-fluid remains a point of contention. Multiple high-resolution platforms for quantitative EV analysis have emerged, including methods grounded in diffraction measurement of Brownian motion (NTA), tunable resistive pulse sensing (TRPS), vesicle flow cytometry (VFC), and transmission electron microscopy (TEM). Here we compared quantitative EV assessment using cerebrospinal fluids derived from glioblastoma patients using these methods. For EVs <150 nm in diameter, NTA detected more EVs than TRPS in three of the four samples tested. VFC particle counts are consistently 2–3 fold lower than NTA and TRPS, suggesting contribution of protein aggregates or other non-lipid particles to particle count by these platforms. While TEM yield meaningful data in terms of the morphology, its particle count are consistently two orders of magnitude lower relative to counts generated by NTA and TRPS. For larger particles (>150 nm in diameter), NTA consistently detected lower number of EVs relative to TRPS. These results unveil the strength and pitfalls of each quantitative method alone for assessing EVs derived from clinical cerebrospinal fluids and suggest that thoughtful synthesis of multi-platform quantitation will be required to guide meaningful clinical investigations. PMID:26901428

  10. Discovery of gramine derivatives that inhibit the early stage of EV71 replication in vitro.

    PubMed

    Wei, Yanhong; Shi, Liqiao; Wang, Kaimei; Liu, Manli; Yang, Qingyu; Yang, Ziwen; Ke, Shaoyong

    2014-01-01

    Enterovirus 71 (EV71) is a notable causative agent of hand, foot, and mouth disease in children, which is associated with an increased incidence of severe neurological disease and death, yet there is no specific treatment or vaccine for EV71 infections. In this study, the antiviral activity of gramine and 21 gramine derivatives against EV71 was investigated in cell-based assays. Eighteen derivatives displayed some degree of inhibitory effects against EV71, in that they could effectively inhibit virus-induced cytopathic effects (CPEs), but the anti-EV71 activity of the lead compound gramine was not observed. Studies on the preliminary modes of action showed that these compounds functioned by targeting the early stage of the EV71 lifecycle after viral entry, rather than inactivating the virus directly, inhibiting virus adsorption or affecting viral release from the cells. Among these derivatives, one (compound 4s) containing pyridine and benzothiazole units showed the most potency against EV71. Further studies demonstrated that derivative 4s could profoundly inhibit viral RNA replication, protein synthesis, and virus-induced apoptosis in RD cells. These results indicate that derivative 4s might be a feasible therapeutic agent against EV71 infection and that these gramine derivatives may provide promising lead scaffolds for the further design and synthesis of potential antiviral agents. PMID:24979400

  11. EV71 vaccine, a new tool to control outbreaks of hand, foot and mouth disease (HFMD).

    PubMed

    Mao, Qun-Ying; Wang, Yiping; Bian, Lianlian; Xu, Miao; Liang, Zhenglun

    2016-05-01

    On December 3rd 2015, the China Food and Drug Administration (CFDA) approved the first inactivated Enterovirus 71 (EV71) whole virus vaccine for preventing severe hand, foot and mouth disease (HFMD). As one of the few preventive vaccines for children's infectious diseases generated by the developing countries in recent years, EV71 vaccine is a blessing to children's health in China and worldwide. However, there are still a few challenges facing the worldwide use of EV71 vaccine, including the applicability against various EV71 pandemic strains in other countries, international requirements on vaccine production and quality control, standardization and harmonization on different pathogen monitoring and detecting methods, etc. In addition, the affordability of EV71 vaccine in other countries is a factor to be considered in HFMD prevention. Therefore, with EV71 vaccine commercially available, there is still a long way to go before reaching effective protection against severe HFMD after EV71 vaccines enter the market. In this paper, the bottlenecks and prospects for the wide use of EV71 vaccine after its approval are evaluated. PMID:26732723

  12. Comparative Analysis of Technologies for Quantifying Extracellular Vesicles (EVs) in Clinical Cerebrospinal Fluids (CSF).

    PubMed

    Akers, Johnny C; Ramakrishnan, Valya; Nolan, John P; Duggan, Erika; Fu, Chia-Chun; Hochberg, Fred H; Chen, Clark C; Carter, Bob S

    2016-01-01

    Extracellular vesicles (EVs) have emerged as a promising biomarker platform for glioblastoma patients. However, the optimal method for quantitative assessment of EVs in clinical bio-fluid remains a point of contention. Multiple high-resolution platforms for quantitative EV analysis have emerged, including methods grounded in diffraction measurement of Brownian motion (NTA), tunable resistive pulse sensing (TRPS), vesicle flow cytometry (VFC), and transmission electron microscopy (TEM). Here we compared quantitative EV assessment using cerebrospinal fluids derived from glioblastoma patients using these methods. For EVs <150 nm in diameter, NTA detected more EVs than TRPS in three of the four samples tested. VFC particle counts are consistently 2-3 fold lower than NTA and TRPS, suggesting contribution of protein aggregates or other non-lipid particles to particle count by these platforms. While TEM yield meaningful data in terms of the morphology, its particle count are consistently two orders of magnitude lower relative to counts generated by NTA and TRPS. For larger particles (>150 nm in diameter), NTA consistently detected lower number of EVs relative to TRPS. These results unveil the strength and pitfalls of each quantitative method alone for assessing EVs derived from clinical cerebrospinal fluids and suggest that thoughtful synthesis of multi-platform quantitation will be required to guide meaningful clinical investigations. PMID:26901428

  13. Search for eV sterile neutrinos at a nuclear reactor — the Stereo project

    NASA Astrophysics Data System (ADS)

    Haser, J.; Stereo Collaboration

    2016-05-01

    The re-analyses of the reference spectra of reactor antineutrinos together with a revised neutrino interaction cross section enlarged the absolute normalization of the predicted neutrino flux. The tension between previous reactor measurements and the new prediction is significant at 2.7 σ and is known as “reactor antineutrino anomaly”. In combination with other anomalies encountered in neutrino oscillation measurements, this observation revived speculations about the existence of a sterile neutrino in the eV mass range. Mixing of this light sterile neutrino with the active flavours would lead to a modification of the detected antineutrino flux. An oscillation pattern in energy and space could be resolved by a detector at a distance of few meters from a reactor core: the neutrino detector of the Stereo project will be located at about 10 m distance from the ILL research reactor in Grenoble, France. Lengthwise separated in six target cells filled with 2 m3 Gd-loaded liquid scintillator in total, the experiment will search for a position-dependent distortion in the energy spectrum.

  14. Design, synthesis, and biological evaluation of anti-EV71 agents.

    PubMed

    Li, Peng; Yang, Bailing; Hao, Fei; Wang, Ping; He, Haiying; Huang, Lei; Zhang, Xuan; Zhang, Shengbin; Peng, Xuanjia; Yin, Ke; Hu, Jiao; Chen, Xinsheng; Gu, Zhengxian; Wang, Li; Shen, Liang; Hu, Guoping; Li, Ning; Li, Jian; Chen, Shuhui; Xiao, Wei; Wang, Zhenzhong; Guo, Qingming; Chang, Xiujuan; Zhang, Lanjun; Cai, Qixu; Lin, Tianwei

    2016-07-15

    Enterovirus 71 (EV71) is a major causative agent of hand, foot and mouth disease (HFMD), which can spread its infections to the central nervous and other systems with severe consequences. In this article, design, chemical synthesis, and biological evaluation of various anti-EV71 agents which incorporate Michael acceptors are described. Further SAR study demonstrated that lactone type of Michael acceptor provided a new lead of anti-EV71 drug candidates with high anti-EV71 activity in cell-based assay and enhanced mouse plasma stability. One of the most potent compounds (2K, cell-based anti-EV71 EC50=0.028μM), showed acceptable stability profile towards mouse plasma, which resulted into promising pharmacokinetics in mouse via IP administration. PMID:27234148

  15. Forecasting the Economic Value of an Enterovirus 71 (EV71) Vaccine

    PubMed Central

    Lee, Bruce Y.; Wateska, Angela R.; Bailey, Rachel R.; Tai, Julie H.Y.; Bacon, Kristina M.; Smith, Kenneth J.

    2010-01-01

    Enterovirus 71 (EV71) is a growing public health concern, especially in Asia. A surge of EV71 cases in 2008 prompted authorities in China to go on national alert. While there is currently no treatment for EV71 infections, vaccines are under development. We developed a computer simulation model to determine the potential economic value of an EV71 vaccine for children (<5 years old) in China. Our results suggest that routine vaccination in China (EV71 infection incidence 0.04%) may be cost-effective when vaccine cost is $25 and efficacy ≥70% or cost is $10 and efficacy ≥ 50%. For populations with higher infection risk (≥ 0.4%), a $50 or $75 vaccine would be highly cost-effective even when vaccine efficacy is as low as 50%. PMID:20923711

  16. STRUCTURAL CHARACTERIZATION OF SULFONATED AZO DYES USING LIQUID SECONDARY ION MASS SPECTROMETRY/TANDEM MASS SPECTROMETRY

    EPA Science Inventory

    Eight monosulfonated and disulfonated azo dyes were analyzed using liquid secondary ion mass spectrometry/tandem mass spectrometry, in the negative ion mode, under low-energy conditions (110-150 eV). any structurally characteristic fragment ions were obtained, several of which ha...

  17. A mass spectroscopic analysis of {gamma}-GPS films

    SciTech Connect

    Dillingham, R.G.; Boerio, F.J.; Bertelsen, C.; Savina, M.R.; Lykke, K.; Calaway, W.

    1996-12-31

    Preparation of substrates for painting or adhesive bonding frequently includes roughening through sanding, chemical etching, or gritblasting. Increased roughness can improve interfacial strength and durability due to increased mechanical interlocking, increased surface area, and improved wettability of the substrate. The chemical reactivity of the surface with the organic phase may be affected as well, perhaps related to the strain energy stored in the surface regions through the intense plastic deformation that occurs. Unfortunately, the chemistry of interactions taking place near a surface that has been roughened is difficult to access analytically by some of the more useful techniques such as infrared spectroscopy. This paper discusses analysis of nonreflective grit-blasted surfaces using mass spectroscopy of species which were either sputtered off using an ion beam (Static Secondary Ion Mass Spectroscopy, or SSIMS) or thermally desorbed as neutrals using a pulsed laser and then post-ionized using a secondary laser (Laser Desorption-Laser Ionization Mass Spectroscopy, or LDLIMS). Both of these techniques exhibit sub-nanometer sensitivity and provide significant information as to the chemistry and structure of the surface regions. In a current application of {gamma}-glycidoxypropyltrimethoxysilane ({gamma}-GPS) for the pre-treatment of grit-blasted aluminum before adhesive bonding, certain factors related to the handling of the primer solution and to the application technique were found to significantly affect the performance of the adhesive bond under long-term aging conditions including stress and humidity. To understand why these parameters are important and to potentially improve the pretreatment process even further, the authors have been investigating how the structure and reactivity of these silane films are related to the application techniques.

  18. Simple mass matrices of neutrinos and quarks consistent with observed mixings and masses

    NASA Astrophysics Data System (ADS)

    Nishiura, Hiroyuki; Fukuyama, Takeshi

    2016-02-01

    We propose a simple phenomenological model of quarks-leptons mass matrices having fundamentally universal symmetry structure. These mass matrices consist of democratic and semi-democratic mass matrix terms commonly to the neutrino and the quark sectors and have only eight free parameters. We show that this mass matrix model well reproduces all the observed values of the MNS lepton and the CKM quark mixing angles, the neutrino mass squared difference ratio, and quark mass ratios, with an excellent agreement. The model also predicts δCPℓ = - 94 ° for the leptonic CP violating phase and < m > ≃ 0.0073 eV for the effective Majorana neutrino mass.

  19. Dual baseline search for muon neutrino disappearance at 0.5 eV2 < Delta m2 < 40 eV2

    DOE PAGESBeta

    Mahn, K B.M.

    2011-06-01

    The SciBooNE and MiniBooNE collaborations report the results of a νμ disappearance search in the Δ'm2 region of 0.5-40 eV2. The neutrino rate as measured by the SciBooNE tracking detectors is used to constrain the rate at the MiniBooNE Cherenkov detector in the first joint analysis of data from both collaborations. Two separate analyses of the combined data samples set 90% confidence level (CL) limits on νμ disappearance in the 0.5-40 eV2 Δm2 region, with an improvement over previous experimental constraints between 10 and 30 eV2

  20. Low-Energy (< 20 eV) and High-Energy (1000 eV) Electron-Induced Methanol Radiolysis of Astrochemical Interest

    NASA Astrophysics Data System (ADS)

    Sullivan, Kristal K.; Boamah, Mavis D.; Shulenberger, Katie E.; Chapman, Sitara; Atkinson, Karen E.; Boyer, Michael C.; Arumainayagam, Christopher R.

    2016-03-01

    We report the first infrared study of the low-energy (< 20 eV) electron-induced reactions of condensed methanol. Our goal is to simulate processes which occur when high-energy cosmic rays interact with interstellar and cometary ices, where methanol, a precursor of several prebiotic species, is relatively abundant. The interactions of high-energy radiation, such as cosmic rays (Emax ˜1020 eV), with matter produce large numbers of low-energy secondary electrons, which are known to initiate radiolysis reactions in the condensed phase. Using temperature programmed desorption (TPD) and infrared reflection absorption spectroscopy (IRAS), we have investigated low-energy (5-20 eV) and high-energy (˜1000 eV) electron-induced reactions in condensed methanol (CH3OH). IRAS has the benefit that it does not require thermal processing prior to product detection. Using IRAS, we have found evidence for the formation of ethylene glycol (HOCH2CH2OH), formaldehyde (CH2O), dimethyl ether (CH3OCH3), methane (CH4), carbon dioxide (CO2), carbon monoxide (CO), and the hydroxyl methyl radical (•CH2OH) upon both low-energy and high-energy electron irradiation of condensed methanol at ˜85 K. Additionally, TPD results, presented herein, are similar for methanol films irradiated with both 1000 eV and 20 eV electrons. These IRAS and TPD findings are qualitatively consistent with the hypothesis that high-energy condensed phase radiolysis is mediated by low-energy electron-induced reactions. Moreover, methoxymethanol (CH3OCH2OH) could serve as a tracer molecule for electron-induced reactions in the interstellar medium. The results of experiments such as ours may provide a fundamental understanding of how complex organic molecules (COM) are synthesized in cosmic ices.

  1. Low-energy (<20 eV) and high-energy (1000 eV) electron-induced methanol radiolysis of astrochemical interest

    NASA Astrophysics Data System (ADS)

    Sullivan, Kristal K.; Boamah, Mavis D.; Shulenberger, Katie E.; Chapman, Sitara; Atkinson, Karen E.; Boyer, Michael C.; Arumainayagam, Christopher R.

    2016-07-01

    We report the first infrared study of the low-energy (<20 eV) electron-induced reactions of condensed methanol. Our goal is to simulate processes which occur when high-energy cosmic rays interact with interstellar and cometary ices, where methanol, a precursor of several prebiotic species, is relatively abundant. The interactions of high-energy radiation, such as cosmic rays (Emax ˜ 1020 eV), with matter produce large numbers of low-energy secondary electrons, which are known to initiate radiolysis reactions in the condensed phase. Using temperature programmed desorption (TPD) and infrared reflection absorption spectroscopy (IRAS), we have investigated low-energy (5-20 eV) and high-energy (˜1000 eV) electron-induced reactions in condensed methanol (CH3OH). IRAS has the benefit that it does not require thermal processing prior to product detection. Using IRAS, we have found evidence for the formation of ethylene glycol (HOCH2CH2OH), formaldehyde (CH2O), dimethyl ether (CH3OCH3), methane (CH4), carbon dioxide (CO2), carbon monoxide (CO), and the hydroxyl methyl radical (·CH2OH) upon both low-energy and high-energy electron irradiation of condensed methanol at ˜85 K. Additionally, TPD results, presented herein, are similar for methanol films irradiated with both 1000 eV and 20 eV electrons. These IRAS and TPD findings are qualitatively consistent with the hypothesis that high-energy condensed phase radiolysis is mediated by low-energy electron-induced reactions. Moreover, methoxymethanol (CH3OCH2OH) could serve as a tracer molecule for electron-induced reactions in the interstellar medium. The results of experiments such as ours may provide a fundamental understanding of how complex organic molecules are synthesized in cosmic ices.

  2. A clinically authentic mouse model of enterovirus 71 (EV-A71)-induced neurogenic pulmonary oedema

    PubMed Central

    Victorio, Carla Bianca Luena; Xu, Yishi; Ng, Qimei; Chua, Beng Hooi; Alonso, Sylvie; Chow, Vincent T. K.; Chua, Kaw Bing

    2016-01-01

    Enterovirus 71 (EV-A71) is a neurotropic virus that sporadically causes fatal neurologic illness among infected children. Animal models of EV-A71 infection exist, but they do not recapitulate in animals the spectrum of disease and pathology observed in fatal human cases. Specifically, neurogenic pulmonary oedema (NPE)—the main cause of EV-A71 infection-related mortality—is not observed in any of these models. This limits their utility in understanding viral pathogenesis of neurologic infections. We report the development of a mouse model of EV-A71 infection displaying NPE in severely affected animals. We inoculated one-week-old BALB/c mice with an adapted EV-A71 strain and identified clinical signs consistent with observations in human cases and other animal models. We also observed respiratory distress in some mice. At necropsy, we found their lungs to be heavier and incompletely collapsed compared to other mice. Serum levels of catecholamines and histopathology of lung and brain tissues of these mice strongly indicated onset of NPE. The localization of virally-induced brain lesions also suggested a potential pathogenic mechanism for EV-A71-induced NPE. This novel mouse model of virally-induced NPE represents a valuable resource for studying viral mechanisms of neuro-pathogenesis and pre-clinical testing of potential therapeutics and prophylactics against EV-A71-related neurologic complications. PMID:27357918

  3. A clinically authentic mouse model of enterovirus 71 (EV-A71)-induced neurogenic pulmonary oedema.

    PubMed

    Victorio, Carla Bianca Luena; Xu, Yishi; Ng, Qimei; Chua, Beng Hooi; Alonso, Sylvie; Chow, Vincent T K; Chua, Kaw Bing

    2016-01-01

    Enterovirus 71 (EV-A71) is a neurotropic virus that sporadically causes fatal neurologic illness among infected children. Animal models of EV-A71 infection exist, but they do not recapitulate in animals the spectrum of disease and pathology observed in fatal human cases. Specifically, neurogenic pulmonary oedema (NPE)-the main cause of EV-A71 infection-related mortality-is not observed in any of these models. This limits their utility in understanding viral pathogenesis of neurologic infections. We report the development of a mouse model of EV-A71 infection displaying NPE in severely affected animals. We inoculated one-week-old BALB/c mice with an adapted EV-A71 strain and identified clinical signs consistent with observations in human cases and other animal models. We also observed respiratory distress in some mice. At necropsy, we found their lungs to be heavier and incompletely collapsed compared to other mice. Serum levels of catecholamines and histopathology of lung and brain tissues of these mice strongly indicated onset of NPE. The localization of virally-induced brain lesions also suggested a potential pathogenic mechanism for EV-A71-induced NPE. This novel mouse model of virally-induced NPE represents a valuable resource for studying viral mechanisms of neuro-pathogenesis and pre-clinical testing of potential therapeutics and prophylactics against EV-A71-related neurologic complications. PMID:27357918

  4. Management approach for NASA's Earth Venture-1 (EV-1) airborne science investigations

    NASA Astrophysics Data System (ADS)

    Guillory, Anthony R.; Denkins, Todd C.; Allen, B. Danette

    2013-09-01

    The Earth System Science Pathfinder (ESSP) Program Office (PO) is responsible for programmatic management of National Aeronautics and Space Administration's (NASA) Science Mission Directorate's (SMD) Earth Venture (EV) missions. EV is composed of both orbital and suborbital Earth science missions. The first of the Earth Venture missions is EV-1, which are Principal Investigator-led, temporally-sustained, suborbital (airborne) science investigations costcapped at $30M each over five years. Traditional orbital procedures, processes and standards used to manage previous ESSP missions, while effective, are disproportionally comprehensive for suborbital missions. Conversely, existing airborne practices are primarily intended for smaller, temporally shorter investigations, and traditionally managed directly by a program scientist as opposed to a program office such as ESSP. In 2010, ESSP crafted a management approach for the successful implementation of the EV-1 missions within the constructs of current governance models. NASA Research and Technology Program and Project Management Requirements form the foundation of the approach for EV-1. Additionally, requirements from other existing NASA Procedural Requirements (NPRs), systems engineering guidance and management handbooks were adapted to manage programmatic, technical, schedule, cost elements and risk. As the EV-1 missions are nearly at the end of their successful execution and project lifecycle and the submission deadline of the next mission proposals near, the ESSP PO is taking the lessons learned and updated the programmatic management approach for all future Earth Venture Suborbital (EVS) missions for an even more flexible and streamlined management approach.

  5. Quantifying EV battery end-of-life through analysis of travel needs with vehicle powertrain models

    NASA Astrophysics Data System (ADS)

    Saxena, Samveg; Le Floch, Caroline; MacDonald, Jason; Moura, Scott

    2015-05-01

    Electric vehicles enable clean and efficient transportation, however concerns about range anxiety and battery degradation hinder EV adoption. The common definition for battery end-of-life is when 70-80% of original energy capacity remains, however little analysis is available to support this retirement threshold. By applying detailed physics-based models of EVs with data on how drivers use their cars, we show that EV batteries continue to meet daily travel needs of drivers well beyond capacity fade of 80% remaining energy storage capacity. Further, we show that EV batteries with substantial energy capacity fade continue to provide sufficient buffer charge for unexpected trips with long distances. We show that enabling charging in more locations, even if only with 120 V wall outlets, prolongs useful life of EV batteries. Battery power fade is also examined and we show EVs meet performance requirements even down to 30% remaining power capacity. Our findings show that defining battery retirement at 70-80% remaining capacity is inaccurate. Battery retirement should instead be governed by when batteries no longer satisfy daily travel needs of a driver. Using this alternative retirement metric, we present results on the fraction of EV batteries that may be retired with different levels of energy capacity fade.

  6. Management Approach for NASA's Earth Venture-1 (EV-1) Airborne Science Investigations

    NASA Technical Reports Server (NTRS)

    Guillory, Anthony R.; Denkins, Todd C.; Allen, B. Danette

    2013-01-01

    The Earth System Science Pathfinder (ESSP) Program Office (PO) is responsible for programmatic management of National Aeronautics and Space Administration's (NASA) Science Mission Directorate's (SMD) Earth Venture (EV) missions. EV is composed of both orbital and suborbital Earth science missions. The first of the Earth Venture missions is EV-1, which are Principal Investigator-led, temporally-sustained, suborbital (airborne) science investigations costcapped at $30M each over five years. Traditional orbital procedures, processes and standards used to manage previous ESSP missions, while effective, are disproportionally comprehensive for suborbital missions. Conversely, existing airborne practices are primarily intended for smaller, temporally shorter investigations, and traditionally managed directly by a program scientist as opposed to a program office such as ESSP. In 2010, ESSP crafted a management approach for the successful implementation of the EV-1 missions within the constructs of current governance models. NASA Research and Technology Program and Project Management Requirements form the foundation of the approach for EV-1. Additionally, requirements from other existing NASA Procedural Requirements (NPRs), systems engineering guidance and management handbooks were adapted to manage programmatic, technical, schedule, cost elements and risk. As the EV-1 missions are nearly at the end of their successful execution and project lifecycle and the submission deadline of the next mission proposals near, the ESSP PO is taking the lessons learned and updated the programmatic management approach for all future Earth Venture Suborbital (EVS) missions for an even more flexible and streamlined management approach.

  7. Electrospray-assisted laser desorption/ionization and tandem mass spectrometry of peptides and proteins.

    PubMed

    Peng, Ivory X; Shiea, Jentaie; Ogorzalek Loo, Rachel R; Loo, Joseph A

    2007-01-01

    We have constructed an electrospray-assisted laser desorption/ionization (ELDI) source which utilizes a nitrogen laser pulse to desorb intact molecules from matrix-containing sample solution droplets, followed by electrospray ionization (ESI) post-ionization. The ELDI source is coupled to a quadrupole ion trap mass spectrometer and allows sampling under ambient conditions. Preliminary data showed that ELDI produces ESI-like multiply charged peptides and proteins up to 29 kDa carbonic anhydrase and 66 kDa bovine albumin from single-protein solutions, as well as from complex digest mixtures. The generated multiply charged polypeptides enable efficient tandem mass spectrometric (MS/MS)-based peptide sequencing. ELDI-MS/MS of protein digests and small intact proteins was performed both by collisionally activated dissociation (CAD) and by nozzle-skimmer dissociation (NSD). ELDI-MS/MS may be a useful tool for protein sequencing analysis and top-down proteomics study, and may complement matrix-assisted laser desorption/ionization (MALDI)-based measurements. PMID:17639579

  8. Direct protein detection from biological media through electrospray-assisted laser desorption ionization/mass spectrometry.

    PubMed

    Huang, Min-Zong; Hsu, Hsiu-Jung; Lee, Jen-Yih; Jeng, Jingyueh; Shiea, Jentaie

    2006-05-01

    We report here using a novel technology-electrospray-assisted laser desorption ionization (ELDI)/mass spectrometry-for the rapid and sensitive detection of the major proteins that exist in dried biological fluids (e.g., blood, tears, saliva, serum), bacterial cultures, and tissues (e.g., porcine liver and heart) under ambient conditions. This technique required essentially no sample pretreatment. The proteins in the samples were desorbed using a pulsed nitrogen laser without the assistance of an organic matrix. The desorbed protein molecules were then post-ionized through their fusion into the charged solvent droplets produced from the electrospray of an acidic methanol solution; electrospray ionization (ESI) proceeded from the newly formed droplets to generate the ESI-like protein ions. This new ionization approach combines some of the features of electrospray ionization with those of matrix-assisted laser desorption ionization (MALDI), that is, sampling of a solid surface with spatial resolution, generating ESI-like mass spectra of the desorbed proteins, and operating under ambient conditions. PMID:16674100

  9. Laser secondary neutral mass spectrometry for copper detection in micro-scale biopsies.

    PubMed

    Kriegeskotte, C; Cantz, T; Haberland, J; Zibert, A; Haier, J; Köhler, G; Schöler, H R; Schmidt, H H-J; Arlinghaus, H F

    2009-10-01

    Disease progression and clinical diagnostics of a number of hereditable metabolic diseases are determined by organ involvement in disturbed deposition of certain molecules. Current clinical imaging is unable to visualize this maldistribution with sufficient specificity and sensitivity, such as in Wilson's disease. The quest for understanding cellular Cu distribution in these patients requires element- and molecule-specific images with nanometer-scale spatial resolution. We have used a new cryo-mass spectrometric instrument with an integrated cryosectioning chamber for preparation and analysis of frozen hydrated samples of Wilson's disease tissue. With laser post-ionization secondary neutral mass spectrometry (laser-SNMS), we were able to image Cu and other intrinsic elements and molecules in less than 1 mg of frozen hydrated liver tissue from a murine model of Wilson's disease. A 40-50 times higher Cu concentration was measured in the disease tissue as compared to the control mouse. Furthermore, major histomorphological changes were observed using this advanced nano-science tool. The results showed that the combination of in-vacuum cryosectioning and cryo-laser-SNMS technologies is particularly well suited for identifying specific cell structures and imaging trace element concentrations with subcellular resolution and upper-parts-per-billion sensitivity in biological samples. This technology can provide a novel diagnostic tool for clinical applications in various diseases involving trace elements. PMID:19753579

  10. Mass spectrometric characterization of elements and molecules in cell cultures and tissues

    NASA Astrophysics Data System (ADS)

    Arlinghaus, H. F.; Kriegeskotte, C.; Fartmann, M.; Wittig, A.; Sauerwein, W.; Lipinsky, D.

    2006-07-01

    Time-of-flight secondary ion mass spectrometry (ToF-SIMS) and laser post-ionization secondary neutral mass spectrometry (laser-SNMS) have been used to image and quantify targeted compounds, intrinsic elements and molecules with subcellular resolution in single cells of both cell cultures and tissues. Special preparation procedures for analyzing cell cultures and tissue materials were developed. Cancer cells type MeWo, incubated with boronated compounds, were sandwiched between two substrates, cryofixed, freeze-fractured and freeze-dried. Also, after injection with boronated compounds, different types of mouse tissues were extracted, prepared on a special specimen carrier and plunged with high velocity into LN 2-cooled propane for cryofixation. After trimming, these tissue blocks were freeze-dried. The measurements of the K/Na ratio demonstrated that for both cell cultures and tissue materials the special preparation techniques used were appropriate for preserving the chemical and structural integrity of the living cell. The boron images show inter- and intracellular boron signals with different intensities. Molecular images show distinct features partly correlated with the cell structure. A comparison between laser-SNMS and ToF-SIMS showed that especially laser-SNMS is particularly well-suited for identifying specific cell structures and imaging ultratrace element concentrations in tissues.

  11. Comparative analysis of EV isolation procedures for miRNAs detection in serum samples

    PubMed Central

    Andreu, Zoraida; Rivas, Eva; Sanguino-Pascual, Aitana; Lamana, Amalia; Marazuela, Mónica; González-Alvaro, Isidoro; Sánchez-Madrid, Francisco; de la Fuente, Hortensia; Yáñez-Mó, María

    2016-01-01

    Extracellular vesicles (EVs) are emerging as potent non-invasive biomarkers. However, current methodologies are time consuming and difficult to translate to clinical practice. To analyse EV-encapsulated circulating miRNA, we searched for a quick, easy and economic method to enrich frozen human serum samples for EV. We compared the efficiency of several protocols and commercial kits to isolate EVs. Different methods based on precipitation, columns or filter systems were tested and compared with ultracentrifugation, which is the most classical protocol to isolate EVs. EV samples were assessed for purity and quantity by nanoparticle tracking analysis and western blot or cytometry against major EV protein markers. For biomarker validation, levels of a set of miRNAs were determined in EV fractions and compared with their levels in total serum. EVs isolated with precipitation-based methods were enriched for a subgroup of miRNAs that corresponded to miRNAs described to be encapsulated into EVs (miR-126, miR-30c and miR-143), while the detection of miR-21, miR-16-5p and miR-19a was very low compared with total serum. Our results point to precipitation using polyethylene glycol (PEG) as a suitable method for an easy and cheap enrichment of serum EVs for miRNA analyses. The overall performance of PEG was very similar, or better than other commercial precipitating reagents, in both protein and miRNA yield, but in comparison to them PEG is much cheaper. Other methods presented poorer results, mostly when assessing miRNA by qPCR analyses. Using PEG precipitation in a longitudinal study with human samples, we demonstrated that miRNA could be assessed in frozen samples up to 8 years of storage. We report a method based on a cut-off value of mean of fold EV detection versus serum that provides an estimate of the degree of encapsulation of a given miRNA. PMID:27330048

  12. Cross sections for 14-eV e-H{sub 2} resonant collisions: Isotope effect in dissociative electron attachment

    SciTech Connect

    Celiberto, R.; Janev, R. K.; Wadehra, J. M.; Laricchiuta, A.

    2011-07-15

    The process of dissociative attachment of electrons to molecular hydrogen and its isotopes in the energy range at approximately 14 eV is investigated. The dissociative electron attachment cross sections for all six hydrogen isotopes are calculated over an extended range of electron energies using the local complex potential model with the excited Rydberg {sup 2}{Sigma}{sub g}{sup +} electronic state of H{sub 2}{sup -} acting as the intermediate resonant state. A significant isotope effect in theoretical electron attachment cross sections is observed, in agreement with previous predictions and experimental observations. A two-parameter analytic expression for the cross section is derived from the theory that fits accurately the numerically calculated cross sections for all isotopes. Similarly, an analytic mass-scaling relation is derived from the theory that accurately reproduces the numerically calculated rate coefficients for all isotopes in the 0.1-1000 eV temperature range by using the rate coefficient for the H{sub 2} isotope only. The latter is represented by an analytic fit expression with two parameters only.

  13. Transfer Excitation Processes Observed in N3+-He and O3+-He Collisions at Elab = 33 eV

    NASA Astrophysics Data System (ADS)

    Itoh, Yoh

    2016-09-01

    We measured the relative state-selective differential cross sections (DCSs) for one-electron capture reactions using a crossed-beam apparatus. The scattering angle θlab studied in the laboratory frame ranged from -3.0 to 22° and the laboratory collision energy Elab was 33 eV. Only the transfer excitation processes, i.e., the electron capture reactions with the simultaneous excitation of the projectile, were observed. The DCSs were determined for the following reactions: N3+ (1s2 2s2 1S) + He (1s2 1S) → N2+ (1s2 2s2p2 2D) + He+ (1s 2S) + 10.3 eV, O3+ (1s2 2s2 2p 2P) + He (1s2 1S) → O2+ (1s2 2s 2p3 3P) + He+ (1s 2S) + 12.7 eV, and O3+ (1s2 2s2 2p 2P) + He (1s2 1S) → O2+ (1s2 2s 2p3 3D) + He+ (1s 2S) + 15.5 eV. In the N3+-He system, the DCSs for the reaction are zero at the center-of-mass angle θcm = 0 and show a peak at a certain angle and a shoulder at a larger angle. In the O3+-He system, the DCSs are again zero at θcm = 0. The capture process to the O2+ (1s2 2s 2p3 3P) state is mainly observed at smaller scattering angles, and the reaction to the O2+ (1s2 2s 2p3 3D) state becomes dominant with increasing scattering angle. A classical trajectory analysis within the two-state approximation based on the ab initio potentials for (NHe)3+ revealed that the transfer excitation of a two-electron process takes place through a single crossing of the relevant potentials.

  14. The origin of 2.7 eV luminescence and 5.2 eV excitation band in hafnium oxide

    SciTech Connect

    Perevalov, T. V.; Aliev, V. Sh.; Gritsenko, V. A.; Saraev, A. A.; Kaichev, V. V.; Ivanova, E. V.; Zamoryanskaya, M. V.

    2014-02-17

    The origin of a blue luminescence band at 2.7 eV and a luminescence excitation band at 5.2 eV of hafnia has been studied in stoichiometric and non-stoichiometric hafnium oxide films. Experimental and calculated results from the first principles valence band spectra showed that the stoichiometry violation leads to the formation of the peak density of states in the band gap caused by oxygen vacancies. Cathodoluminescence in the non-stoichiometric film exhibits a band at 2.65 eV that is excited at the energy of 5.2 eV. The optical absorption spectrum calculated for the cubic phase of HfO{sub 2} with oxygen vacancies shows a peak at 5.3 eV. Thus, it could be concluded that the blue luminescence band at 2.7 eV and HfO{sub x} excitation peak at 5.2 eV are due to oxygen vacancies. The thermal trap energy in hafnia was estimated.

  15. EV71 vaccines: a first step towards multivalent hand, foot and mouth disease vaccines.

    PubMed

    Klein, Michel H

    2015-03-01

    Enterovirus A infections are the primary cause of hand, foot and mouth disease in infants and young children. Enterovirus 71 (EV71) and coxsackievirus A16 have emerged as neurotropic viruses responsible for severe neurological complications and a serious public health threat across the Asia-Pacific region. Formalin-inactivated EV71 vaccines have elicited protection against EV71 but not against coxsackievirus A16 infections. The development of a bivalent formalin-inactivated EV71/FI coxsackievirus A16 vaccine should be the next step towards that of multivalent hand, foot and mouth disease vaccines which should ultimately include other prevalent pathogenic coxsackieviruses and echovirus 30. This editorial summarizes the major challenges faced by the development of hand, foot and mouth disease vaccines. PMID:25536888

  16. Marshall Space Flight Center In-House Earned Value System (EVS)

    NASA Technical Reports Server (NTRS)

    Smith, Donnie

    2004-01-01

    The Earned Value System (EVS) is a project management budgeting and scheduling process for in-house project and institutional applications. This viewgraph presentation includes images of the system's computer interface.

  17. Analysis of Cross-Reactive Neutralizing Antibodies in Human HFMD Serum with an EV71 Pseudovirus-Based Assay

    PubMed Central

    Jin, Jun; Xu, Lin; Sun, Shiyang; Jiang, Liping; Li, Xiaojun; Shao, Jie; Ma, Hongxia; Huang, Xueyong; Guo, Shijie; Chen, Haiying; Cheng, Tong; Yang, Lisheng; Su, Weiheng; Kong, Wei; Liang, Zhenglun; Jiang, Chunlai

    2014-01-01

    Hand, foot and mouth disease, associated with enterovirus 71 (EV71) infections, has recently become an important public health issue throughout the world. Serum neutralizing antibodies are major indicators of EV71 infection and protective immunity. However, the potential for cross-reactivity of neutralizing antibodies for different EV71 genotypes and subgenotypes is unclear. Here we measured the cross-reactive neutralizing antibody titers against EV71 of different genotypes or subgenotypes in sera collected from EV71-infected children and vaccine-inoculated children in a phase III clinical trial (ClinicalTrials.gov Identifier: NCT01636245) using a new pseudovirus-based neutralization assay. Antibodies induced by EV71-C4a were cross-reactive for different EV71 genotypes, demonstrating that C4a is a good candidate strain for an EV71 vaccine. Our study also demonstrated that this new assay is practical for analyses of clinical samples from epidemiological and vaccine studies. PMID:24964084

  18. Time distribution of EAS with E>10/sup 14/ eV

    SciTech Connect

    CHEN Ying-xuan; HE Chang-xiao; XIAO Qian-yi; WANG Li-xiang

    1986-01-01

    We have observed the arrival times of EAS initiated by cosmic rays of E>10/sup 14/ eV using the EAS array in Beijing. The distribution of arrival time intervals of EAS with E>2.6 x 10/sup 14/ eV is considerably higher than the exponential distribution in the region of time intervals t<21 second. It is suggested that a time correlation component is probably present in the EAS events.

  19. Cultural and morphological properties of the vaccine strain Yersinia pestis EV NIIEG bacteria after photodynamic inactivation

    NASA Astrophysics Data System (ADS)

    Ulianova, Onega V.; Lyapina, Anna M.; Khizhnyakova, Mariya A.; Laskavy, Vladislav N.; Feodorova, Valentina A.; Ulyanov, Sergey S.

    2015-03-01

    New method of photoinactivation of plague microbes (bacteria Yersinia pestis) has been suggested. Rate of growth of colonies of Y. pestis EV NIIEG at specific regimes of photo processing have been analyzed. Dependence of growth on exposure time and concentrations of photosensitizer (methylene blue) has been studied. Number of colony forming units of Y. pestis EV NIIEG bacteria as a function of intensity of light and concentration of methylene blue has been scrutinized.

  20. Relative fluorescent efficiency of sodium salicylate between 90 and 800 eV

    NASA Technical Reports Server (NTRS)

    Angel, G. C.; Samson, J. A. R.; Wiliams, G.

    1986-01-01

    The relative fluorescent quantum efficiency of sodium salicylate was measured between 90 and 800 eV (138-15 A) by the use of synchrotron radiation. A general increase in efficiency was observed in this spectral range except for abrupt decreases in efficiency at the carbon and oxygen K-edges. Beyond the oxygen K-edge (532 eV) the efficiency increased linearly with the incident photon energy to the limit of the present observations.

  1. HEAP---An instrument to measure the elemental abundances above 10 sup 15 eV at a lunar base

    SciTech Connect

    Swordy, S.P. )

    1990-03-20

    At {approx}10{sup 15} eV the slope of the energy spectrum of cosmic rays becomes significantly steeper than at lower energies. The measurement of relative elemental abundances at these energies is expected to provide a means to resolve the origin of this feature and greatly contribute to the understanding of the sources of cosmic rays at high energies. We describe a moon based detector, HEAP, for making well-resolved elemental measurements at these energies using hadronic calorimetry. This detector is particularly well suited for a site on the lunar surface because there is no overlying layer of atmosphere and the large mass required can be provided by the lunar regolith.

  2. Human RHOH deficiency causes T cell defects and susceptibility to EV-HPV infections

    PubMed Central

    Crequer, Amandine; Troeger, Anja; Patin, Etienne; Ma, Cindy S.; Picard, Capucine; Pedergnana, Vincent; Fieschi, Claire; Lim, Annick; Abhyankar, Avinash; Gineau, Laure; Mueller-Fleckenstein, Ingrid; Schmidt, Monika; Taieb, Alain; Krueger, James; Abel, Laurent; Tangye, Stuart G.; Orth, Gérard; Williams, David A.; Casanova, Jean-Laurent; Jouanguy, Emmanuelle

    2012-01-01

    Epidermodysplasia verruciformis (EV) is a rare genetic disorder characterized by increased susceptibility to specific human papillomaviruses, the betapapillomaviruses. These EV-HPVs cause warts and increase the risk of skin carcinomas in otherwise healthy individuals. Inactivating mutations in epidermodysplasia verruciformis 1 (EVER1) or EVER2 have been identified in most, but not all, patients with autosomal recessive EV. We found that 2 young adult siblings presenting with T cell deficiency and various infectious diseases, including persistent EV-HPV infections, were homozygous for a mutation creating a stop codon in the ras homolog gene family member H (RHOH) gene. RHOH encodes an atypical Rho GTPase expressed predominantly in hematopoietic cells. Patients’ circulating T cells contained predominantly effector memory T cells, which displayed impaired TCR signaling. Additionally, very few circulating T cells expressed the β7 integrin subunit, which homes T cells to specific tissues. Similarly, Rhoh-null mice exhibited a severe overall T cell defect and abnormally small numbers of circulating β7-positive cells. Expression of the WT, but not of the mutated RHOH, allele in Rhoh–/– hematopoietic stem cells corrected the T cell lymphopenia in mice after bone marrow transplantation. We conclude that RHOH deficiency leads to T cell defects and persistent EV-HPV infections, suggesting that T cells play a role in the pathogenesis of chronic EV-HPV infections. PMID:22850876

  3. Two models for changes of EV71 immunity in infants and young children

    PubMed Central

    Tu, Xiaoming; Wang, Yongmei; Zhu, Fengcai; Chen, Feng

    2015-01-01

    Human enterovirus 71 (EV71) has been associated with outbreaks of hand-foot-and-mouth disease (HFMD) in China. Susceptibility to EV71 is associated with age, but few studies have been accomplished to measure such a relationship. A better understanding of the connection between susceptibility and age is necessary to develop strategies for control of HFMD. In 2010, a survey of an epidemic of EV71 was conducted in a northern city of Jiangsu Province in China. Samples were tested serologically to identify the EV71 neutralizing antibody. Two different mathematical models have now been employed to describe how this antibody varied with age, and parameters in the model were estimated from survey data. Both models depicted the variations in EV71-neutralizing antibody. Seroprevalence was high for neonates but decreased to near zero at 5 months of age. Subsequently, the EV71 antibody levels increased and then remained stable after about 36 months. For models 1 and 2, values for the coefficient of determination (R2) were 0.9458 and 0.9576, and values for root mean square error (RMSE) were 0.0755 and 0.0752, respectively. Model 2, formulated from the characteristics of development of the immune system, was more reliable than model 1, formulated from survey data, because the impact of the survey on the structure of the model was removed. Moreover, model 2 provided the possibility to define the parameters in a biological sense. PMID:25906390

  4. Two models for changes of EV71 immunity in infants and young children.

    PubMed

    Tu, Xiaoming; Wang, Yongmei; Zhu, Fengcai; Chen, Feng

    2015-01-01

    Human enterovirus 71 (EV71) has been associated with outbreaks of hand-foot-and-mouth disease (HFMD) in China. Susceptibility to EV71 is associated with age, but few studies have been accomplished to measure such a relationship. A better understanding of the connection between susceptibility and age is necessary to develop strategies for control of HFMD. In 2010, a survey of an epidemic of EV71 was conducted in a northern city of Jiangsu Province in China. Samples were tested serologically to identify the EV71 neutralizing antibody. Two different mathematical models have now been employed to describe how this antibody varied with age, and parameters in the model were estimated from survey data. Both models depicted the variations in EV71-neutralizing antibody. Seroprevalence was high for neonates but decreased to near zero at 5 months of age. Subsequently, the EV71 antibody levels increased and then remained stable after about 36 months. For models 1 and 2, values for the coefficient of determination (R(2)) were 0.9458 and 0.9576, and values for root mean square error (RMSE) were 0.0755 and 0.0752, respectively. Model 2, formulated from the characteristics of development of the immune system, was more reliable than model 1, formulated from survey data, because the impact of the survey on the structure of the model was removed. Moreover, model 2 provided the possibility to define the parameters in a biological sense. PMID:25906390

  5. Complete Genome Analysis of an Enterovirus EV-B83 Isolated in China

    PubMed Central

    Tang, Jingjing; Li, Qiongfen; Tian, Bingjun; Zhang, Jie; Li, Kai; Ding, Zhengrong; Lu, Lin

    2016-01-01

    Enterovirus B83 (EV-B83) is a recently identified member of enterovirus species B. It is a rarely reported serotype and up to date, only the complete genome sequence of the prototype strain from the United States is available. In this study, we describe the complete genomic characterization of an EV-B83 strain 246/YN/CHN/08HC isolated from a healthy child living in border region of Yunnan Province, China in 2008. Compared with the prototype strain, it had 79.6% similarity in the complete genome and 78.9% similarity in the VP1 coding region, reflecting the great genetic divergence among them. VP1-coding region alignment revealed it had 77.2–91.3% with other EV-B83 sequences available in GenBank. Similarity plot analysis revealed it had higher identity with several other EV-B serotypes than the EV-B83 prototype strain in the P2 and P3 coding region, suggesting multiple recombination events might have occurred. The great genetic divergence with previously isolated strains and the extremely rare isolation suggest this serotype has circulated at a low epidemic strength for many years. This is the first report of complete genome of EV-B83 in China. PMID:27405393

  6. Complete Genome Analysis of an Enterovirus EV-B83 Isolated in China.

    PubMed

    Tang, Jingjing; Li, Qiongfen; Tian, Bingjun; Zhang, Jie; Li, Kai; Ding, Zhengrong; Lu, Lin

    2016-01-01

    Enterovirus B83 (EV-B83) is a recently identified member of enterovirus species B. It is a rarely reported serotype and up to date, only the complete genome sequence of the prototype strain from the United States is available. In this study, we describe the complete genomic characterization of an EV-B83 strain 246/YN/CHN/08HC isolated from a healthy child living in border region of Yunnan Province, China in 2008. Compared with the prototype strain, it had 79.6% similarity in the complete genome and 78.9% similarity in the VP1 coding region, reflecting the great genetic divergence among them. VP1-coding region alignment revealed it had 77.2-91.3% with other EV-B83 sequences available in GenBank. Similarity plot analysis revealed it had higher identity with several other EV-B serotypes than the EV-B83 prototype strain in the P2 and P3 coding region, suggesting multiple recombination events might have occurred. The great genetic divergence with previously isolated strains and the extremely rare isolation suggest this serotype has circulated at a low epidemic strength for many years. This is the first report of complete genome of EV-B83 in China. PMID:27405393

  7. Calculations of electron stopping powers for 41 elemental solids over the 50 eV to 30 keV range with the full Penn algorithm

    NASA Astrophysics Data System (ADS)

    Shinotsuka, H.; Tanuma, S.; Powell, C. J.; Penn, D. R.

    2012-01-01

    We present mass collision electron stopping powers (SPs) for 41 elemental solids (Li, Be, graphite, diamond, glassy C, Na, Mg, Al, Si, K, Sc, Ti, V, Cr, Fe, Co, Ni, Cu, Ge, Y, Nb, Mo, Ru, Rh, Pd, Ag, In, Sn, Cs, Gd, Tb, Dy, Hf, Ta, W, Re, Os, Ir, Pt, Au, and Bi) that were calculated from experimental energy-loss-function data with the full Penn algorithm for electron energies between 50 eV and 30 keV. Improved sets of energy-loss functions were used for 19 solids. Comparisons were made of these SPs with SPs calculated with the single-pole approximation, previous SP calculations, and experimental SPs. Generally satisfactory agreement was found with SPs from the single-pole approximation for energies above 100 eV, with other calculated SPs, and with measured SPs.

  8. Fluorescence Detection of Cosmic Ray Air Showers Between 1016.5 and 1018.5 eV with the Telescope Array Low Energy Extension (TALE)

    NASA Astrophysics Data System (ADS)

    Zundel, Zachary

    The Telescope Array (TA) Collaboration has completed construction of a low-energy extension to its Middle Drum telescope station. Ten new telescopes were added observing 32-59 degrees in elevation above the original telescopes. A graded array of scintillator detectors (SDs) with spacings of 400-600-1200 m is being installed in front of the telescope station. With these upgrades, the physics threshold will be lowered below 1016.5 eV. The TA Low Energy Extension (TALE) will explore the regime corresponding to the LHC center-of-mass energy. This is also the region where the transition from galactic to extra-galactic cosmic ray flux is suspected to occur. A brief overview of the physics is presented as well as a report on the progress toward measuring the cosmic ray spectrum between 1016.5 and 1018.5 eV.

  9. Commercial Electric Vehicle (EV) Development and Manufacturing Program

    SciTech Connect

    Leeve, Dion

    2014-06-30

    Navistar with the Department of Energy’s assistance undertook this effort to achieve the project objectives as listed in the next section. A wholly owned subsidiary of Navistar, Workhorse Sales Corporation was the original grant awardee and upon their discontinuation as a standalone business entity, Navistar assumed the role of principal investigator. The intent of the effort, as part of the American Recovery and Reinvestment Act (ARRA) was to produce zero emission vehicles that could meet the needs of the marketplace while reducing carbon emissions to zero. This effort was predicated upon the assumption that concurrent development activities in the lithium ion battery industry investigations would significantly increase their production volumes thus leading to substantial reductions in their manufacturing costs. As a result of this development effort much was learned about the overall system compatibility between the electric motor, battery pack, and charging capabilities. The original system was significantly revised and improved during the execution of this development effort. The overall approach that was chosen was to utilize a British zero emissions, class 2 truck that had been developed for their market, homologate it and modify it to meet the product requirements as specified in the grant details. All of these specific goals were achieved. During the course of marketing and selling the product valuable information was obtained as relates to customer expectations, price points, and product performance expectations, specifically those customer expectations about range requirements in urban delivery situations. While the grant requirements specified a range of 100 miles on a single charge, actual customer usage logs indicate a range of 40 miles or less is typical for their applications. The price point, primarily due to battery pack costs, was significantly higher than the mass market could bear. From Navistar’s and the overall industry’s perspective

  10. Time-of-flight secondary neutral & ion mass spectrometry using swift heavy ions

    NASA Astrophysics Data System (ADS)

    Breuer, L.; Meinerzhagen, F.; Bender, M.; Severin, D.; Wucher, A.

    2015-12-01

    We report on a new time-of-flight (TOF) spectrometer designed to investigate sputtering phenomena induced by swift heavy ions in the electronic stopping regime. In this experiment, particular emphasis is put on the detection of secondary ions along with their emitted neutral counterparts in order to examine the ionization efficiency of the sputtered material. For the detection of neutral species, the system is equipped with a pulsed VUV laser for post-ionization of sputtered neutral atoms and molecules via single photon ionization at a wavelength of 157 nm (corresponding to 7.9 eV photon energy). For alignment purposes and in order to facilitate comparison to nuclear sputtering conditions, the system also includes a 5 keV Ar+ ion beam directed to the same sample area. The instrument has been added to the M1-branch beam line at the German accelerator facility in Darmstadt (GSI) and was tested with 4.8 MeV/u Au26+ ions impinging onto various samples including metals, salts and organic films. It is found that secondary ion and neutral spectra obtained under both bombardment conditions can be acquired in an interleaved manner throughout a single accelerator pulse cycle, thus making efficient use of valuable beam time. In addition, the keV ion beam can be intermittently switched to dc mode between subsequent data acquisition windows and accelerator pulses in order to ensure reproducible surface conditions. For the case of a dynamically sputter cleaned metal surface, comparison of secondary ion and neutral signals obtained under otherwise identical instrumental conditions reveals a nearly identical ionization probability of atoms emitted under electronic and nuclear sputtering conditions.

  11. Identification of specific antigenic epitope at N-terminal segment of enterovirus 71 (EV-71) VP1 protein and characterization of its use in recombinant form for early diagnosis of EV-71 infection

    PubMed Central

    Zhang, Jianhua; Jiang, Bingfu; Xu, Mingjie; Dai, Xing; Purdy, Michael A.; Meng, Jihong

    2015-01-01

    Human enterovirus 71 (EV-71) is the main etiologic agent of hand, foot and mouth disease (HFMD). We sought to identify EV-71 specific antigens and develop serologic assays for acute-phase EV-71 infection. A series of truncated proteins within the N-terminal 100 amino acids (aa) of EV-71 VP1 was expressed in Escherichia coli. Western blot (WB) analysis showed that positions around 11–21 aa contain EV-71-specific antigenic sites, whereas positions 1–5 and 51–100 contain epitopes shared with human coxsackievirus A16 (CV-A16) and human echovirus 6 (E-6). The N-terminal truncated protein of VP1, VP16–43, exhibited good stability and was recognized by anti-EV-71 specific rabbit sera. Alignment analysis showed that VP16–43 is highly conserved among EV-71 strains from different genotypes but was heterologous among other enteroviruses. When the GST-VP16–43 fusion protein was incorporated as antibody-capture agent in a WB assay and an ELISA for detecting anti-EV-71 IgM in human sera, sensitivities of 91.7% and 77.8% were achieved, respectively, with 100% specificity for both. The characterized EV-71 VP1 protein truncated to positions 6–43 aa has potential as an antigen for detection of anti-EV-71 IgM for early diagnosis of EV-71 infection in a WB format. PMID:24952304

  12. Circular intensity differential scattering (CIDS) measurements in the soft x-ray region of the spectrum (@16 eV to 500 eV)

    SciTech Connect

    Maestre, M.F. ); Bustamante, C. . Dept. of Chemistry); Snyder, P. . Dept. of Chemistry); Rowe, E.; Hansen, R. . Synchrotron Radiation Center)

    1991-03-01

    We propose the use of recently developed techniques of circular intensity differential scattering (CIDS), as extended to the soft x-ray region of the spectrum (16 eV to 500 eV), to study the higher order organization of the eukaryotic chromosome. CIDS is the difference in scattering power of an object when illuminated by right circularly polarized vs. left circularly polarized electromagnetic radiation of arbitrary wavelength. CIDS has been shown to be a very sensitive measure of the helical organization of the scattering object eg. the eukaryotic chromosome. Preliminary results of measurements of samples of bacteriophages and octopus sperm done at SRC, Wisconsin, show the technique to be very sensitive to the dimensional parameters of the particles interrogated by circularly polarized light. 7 refs., 5 figs.

  13. X-ray grating spectrometer for opacity measurements in the 50 eV to 250 eV spectral range at the LULI 2000 laser facility.

    PubMed

    Reverdin, Charles; Thais, Frédéric; Loisel, Guillaume; Busquet, M; Bastiani-Ceccotti, S; Blenski, T; Caillaud, T; Ducret, J E; Foelsner, W; Gilles, D; Gilleron, F; Pain, J C; Poirier, M; Serres, F; Silvert, V; Soullie, G; Turck-Chieze, S; Villette, B

    2012-10-01

    An x-ray grating spectrometer was built in order to measure opacities in the 50 eV to 250 eV spectral range with an average spectral resolution ∼ 50. It has been used at the LULI-2000 laser facility at École Polytechnique (France) to measure the Δn = 0, n = 3 transitions of several elements with neighboring atomic number: Cr, Fe, Ni, and Cu in the same experimental conditions. Hence a spectrometer with a wide spectral range is required. This spectrometer features one line of sight looking through a heated sample at backlighter emission. It is outfitted with one toroidal condensing mirror and several flat mirrors cutting off higher energy photons. The spectral dispersion is obtained with a flatfield grating. Detection consists of a streak camera sensitive to soft x-ray radiation. Some experimental results showing the performance of this spectrometer are presented. PMID:23126955

  14. X-ray grating spectrometer for opacity measurements in the 50 eV to 250 eV spectral range at the LULI 2000 laser facilitya)

    NASA Astrophysics Data System (ADS)

    Reverdin, Charles; Thais, Frédéric; Loisel, Guillaume; Busquet, M.; Bastiani-Ceccotti, S.; Blenski, T.; Caillaud, T.; Ducret, J. E.; Foelsner, W.; Gilles, D.; Gilleron, F.; Pain, J. C.; Poirier, M.; Serres, F.; Silvert, V.; Soullie, G.; Turck-Chieze, S.; Villette, B.

    2012-10-01

    An x-ray grating spectrometer was built in order to measure opacities in the 50 eV to 250 eV spectral range with an average spectral resolution ⟨E/δE⟩ ˜ 50. It has been used at the LULI-2000 laser facility at École Polytechnique (France) to measure the Δn = 0, n = 3 transitions of several elements with neighboring atomic number: Cr, Fe, Ni, and Cu in the same experimental conditions. Hence a spectrometer with a wide spectral range is required. This spectrometer features one line of sight looking through a heated sample at backlighter emission. It is outfitted with one toroidal condensing mirror and several flat mirrors cutting off higher energy photons. The spectral dispersion is obtained with a flatfield grating. Detection consists of a streak camera sensitive to soft x-ray radiation. Some experimental results showing the performance of this spectrometer are presented.

  15. X-ray grating spectrometer for opacity measurements in the 50 eV to 250 eV spectral range at the LULI 2000 laser facility

    SciTech Connect

    Reverdin, Charles; Caillaud, T.; Gilleron, F.; Pain, J. C.; Silvert, V.; Soullie, G.; Villette, B.; Thais, Frederic; Loisel, Guillaume; Blenski, T.; Poirier, M.; Busquet, M.; Bastiani-Ceccotti, S.; Serres, F.; Ducret, J. E.; Foelsner, W.; Gilles, D.; Turck-Chieze, S.

    2012-10-15

    An x-ray grating spectrometer was built in order to measure opacities in the 50 eV to 250 eV spectral range with an average spectral resolution {approx} 50. It has been used at the LULI-2000 laser facility at Ecole Polytechnique (France) to measure the {Delta}n = 0, n = 3 transitions of several elements with neighboring atomic number: Cr, Fe, Ni, and Cu in the same experimental conditions. Hence a spectrometer with a wide spectral range is required. This spectrometer features one line of sight looking through a heated sample at backlighter emission. It is outfitted with one toroidal condensing mirror and several flat mirrors cutting off higher energy photons. The spectral dispersion is obtained with a flatfield grating. Detection consists of a streak camera sensitive to soft x-ray radiation. Some experimental results showing the performance of this spectrometer are presented.

  16. Usage of Electric Vehicle Supply Equipment Along the Corridors between the EV Project Major Cities

    SciTech Connect

    Mindy Kirkpatrick

    2012-05-01

    The report explains how the EVSE are being used along the corridors between the EV Project cities. The EV Project consists of a nationwide collaboration between Idaho National Laboratory (INL), ECOtality North America, Nissan, General Motors, and more than 40 other city, regional and state governments, and electric utilities. The purpose of the EV Project is to demonstrate the deployment and use of approximately 14,000 Level II (208-240V) electric vehicle supply equipment (EVSE) and 300 fast chargers in 16 major cities. This research investigates the usage of all currently installed EV Project commercial EVSE along major interstate corridors. ESRI ArcMap software products are utilized to create geographic EVSE data layers for analysis and visualization of commercial EVSE usage. This research locates the crucial interstate corridors lacking sufficient commercial EVSE and targets locations for future commercial EVSE placement. The results and methods introduced in this research will be used by INL for the duration of the EV Project.

  17. MSC secretes at least 3 EV types each with a unique permutation of membrane lipid, protein and RNA

    PubMed Central

    Lai, Ruenn Chai; Tan, Soon Sim; Yeo, Ronne Wee Yeh; Choo, Andre Boon Hwa; Reiner, Agnes T.; Su, Yan; Shen, Yang; Fu, Zhiyan; Alexander, Lezhava; Sze, Siu Kwan; Lim, Sai Kiang

    2016-01-01

    Mesenchymal stem cell (MSC), a widely used adult stem cell candidate for regenerative medicine, has been shown to exert some of its therapeutic effects through the secretion of extracellular vesicles (EVs). These homogenously sized EVs of 100–150 ηm exhibited many exosome-like biophysical and biochemical properties and carry both proteins and RNAs. Recently, exosome-associated proteins in this MSC EV preparation were found to segregate primarily to those EVs that bind cholera toxin B chain (CTB), a GM1 ganglioside-specific ligand, and pulse-chase experiments demonstrated that these EVs have endosomal origin and carried many of the exosome-associated markers. Here, we report that only a fraction of the MSC EV proteome was found in CTB-bound EVs. Using Annexin V (AV) and Shiga toxin B subunit (ST) with affinities for phosphatidylserine and globotriaosylceramide, respectively, AV- and a ST-binding EV were identified. CTB-, AV- and ST–binding EVs all carried actin. However, the AV-binding EVs carried low or undetectable levels of the exosome-associated proteins. Only the ST-binding EVs carried RNA and EDA-containing fibronectin. Proteins in AV-binding EVs were also different from those released by apoptotic MSCs. CTB- and AV-binding activities were localized to the plasma membrane and cytoplasm of MSCs, while ST-binding activity was localized to the nucleus. Together, this study demonstrates that cells secrete many types of EVs. Specifically, MSCs secrete at least 3 types. They can be differentially isolated based on their affinities for membrane lipid-binding ligands. As the subcellular sites of the binding activities of these ligands and cargo load are different for each EV type, they are likely to have a different biogenesis pathway and possibly different functions. PMID:26928672

  18. The Evolution of Vp1 Gene in Enterovirus C Species Sub-Group That Contains Types CVA-21, CVA-24, EV-C95, EV-C96 and EV-C99

    PubMed Central

    Smura, Teemu; Blomqvist, Soile; Vuorinen, Tytti; Ivanova, Olga; Samoilovich, Elena; Al-Hello, Haider; Savolainen-Kopra, Carita; Hovi, Tapani; Roivainen, Merja

    2014-01-01

    Genus Enterovirus (Family Picornaviridae,) consists of twelve species divided into genetically diverse types by their capsid protein VP1 coding sequences. Each enterovirus type can further be divided into intra-typic sub-clusters (genotypes). The aim of this study was to elucidate what leads to the emergence of novel enterovirus clades (types and genotypes). An evolutionary analysis was conducted for a sub-group of Enterovirus C species that contains types Coxsackievirus A21 (CVA-21), CVA-24, Enterovirus C95 (EV-C95), EV-C96 and EV-C99. VP1 gene datasets were collected and analysed to infer the phylogeny, rate of evolution, nucleotide and amino acid substitution patterns and signs of selection. In VP1 coding gene, high intra-typic sequence diversities and robust grouping into distinct genotypes within each type were detected. Within each type the majority of nucleotide substitutions were synonymous and the non-synonymous substitutions tended to cluster in distinct highly polymorphic sites. Signs of positive selection were detected in some of these highly polymorphic sites, while strong negative selection was indicated in most of the codons. Despite robust clustering to intra-typic genotypes, only few genotype-specific ‘signature’ amino acids were detected. In contrast, when different enterovirus types were compared, there was a clear tendency towards fixation of type-specific ‘signature’ amino acids. The results suggest that permanent fixation of type-specific amino acids is a hallmark associated with evolution of different enterovirus types, whereas neutral evolution and/or (frequency-dependent) positive selection in few highly polymorphic amino acid sites are the dominant forms of evolution when strains within an enterovirus type are compared. PMID:24695547

  19. Ion and electron bombardment-related ion emission during the analysis of diamond using secondary ion mass spectrometry

    SciTech Connect

    Guzman de la Mata, Berta; Dowsett, Mark G.

    2007-02-01

    In recent years, the ability to grow single crystal layers of both doped and pure diamonds has improved, and devices for applications in high power electronics and microelectronics are being developed, most of them based on boron doped diamond. In this work, convoluted angular and energy spectra (so-called secondary ion mass spectrometry energy spectra) have been measured for {sup 11}B{sup +}, {sup 12}C{sup +}, {sup 16}O{sup +}, CO{sup +} and CO{sub 2}{sup +} ions ejected from a single crystal boron doped diamond layer under ultralow energy oxygen and electron beam bombardment. A low energy tail was observed in the {sup 12}C{sup +}, CO{sup +}, and CO{sub 2}{sup +} signals, corresponding to ions produced in the gas phase. Changing the bombardment conditions, we have identified interaction with the electron beam as the main ionization mechanism. In the case of {sup 12}C{sup +} it appears that the gas phase ions are produced by electron stimulated desorption and postionization of surface species created by the oxygen beam. We have detected high signals for CO{sup +} and CO{sub 2}{sup +} ionized in the gas phase, which supports a mechanism previously suggested to explain the anomalously fast diamond erosion under oxygen ion beam bombardment. We also observe that some species appearing in the mass spectrum are produced by electron stimulated desorption and this needs to be remembered when analyzing these on insulating diamond with charge compensation.

  20. Mass-spectrometry-based molecular characterization of extracellular vesicles: lipidomics and proteomics.

    PubMed

    Kreimer, Simion; Belov, Arseniy M; Ghiran, Ionita; Murthy, Shashi K; Frank, David A; Ivanov, Alexander R

    2015-06-01

    This review discusses extracellular vesicles (EVs), which are submicron-scale, anuclear, phospholipid bilayer membrane enclosed vesicles that contain lipids, metabolites, proteins, and RNA (micro and messenger). They are shed from many, if not all, cell types and are present in biological fluids and conditioned cell culture media. The term EV, as coined by the International Society of Extracellular Vesicles (ISEV), encompasses exosomes (30-100 nm in diameter), microparticles (100-1000 nm), apoptotic blebs, and other EV subsets. EVs have been implicated in cell-cell communication, coagulation, inflammation, immune response modulation, and disease progression. Multiple studies report that EV secretion from disease-affected cells contributes to disease progression, e.g., tumor niche formation and cancer metastasis. EVs are attractive sources of biomarkers due to their biological relevance and relatively noninvasive accessibility from a range of physiological fluids. This review is focused on the molecular profiling of the protein and lipid constituents of EVs, with emphasis on mass-spectrometry-based "omic" analytical techniques. The challenges in the purification and molecular characterization of EVs, including contamination of isolates and limitations in sample quantities, are discussed along with possible solutions. Finally, the review discusses the limited but growing investigation of post-translational modifications of EV proteins and potential strategies for future in-depth molecular characterization of EVs. PMID:25927954

  1. Energy transfer from noble-gas ions to surfaces: Collisions with carbon, silicon, copper, silver, and gold in the range 100--4000 eV

    SciTech Connect

    Coufal, H.; Winters, H.F.; Bay, H.L. ); Eckstein, W. )

    1991-09-01

    The energy deposited into carbon, silicon, copper, silver, and gold surfaces by He{sup +}, Ar{sup +}, and Xe{sup +} ions impinging with kinetic energy in the range 100--4000 eV has been measured. These studies employed a highly sensitive calorimeter together with a modified physical electronics instrument ion gun. Pulses of ions from the gun were directed at the film that had been evaporated directly onto the pyroelectric material. A voltage proportional to the energy deposited is developed across the material and sensed with a lock-in detector. Xe{sup +} deposits more than 95% of its energy between 500 and 4000 eV for all materials. The other ions deposit at least 80% of their energy in this range. The dependence of energy deposition upon ion and substrate mass and ion energy is about that expected from calculations and physical principles. The energy reflection from surfaces is also investigated by computer simulation using the TRIM.SP program. The experimental trends are semiquantitatively reproduced by the simulation, but there are some quantitative differences in the absolute results. As would be expected from previous calculations, the energy-reflection coefficients do not appear to scale with the ratio of target mass to ion mass or with reduced energy. The implication of these results for the understanding of collisional processes at solid surfaces will be discussed.

  2. Project of Antarctic Balloon-Borne Measurements of the CR spectrum above 1020 EV.

    NASA Astrophysics Data System (ADS)

    Antonov, R. A.; Kuzmichev, L. A.; Panasyuk, M. I.; Chernov, D. V.; Nikolsky, S. I.; Sysojeva, T. I.

    Relatively simple detector SPHERE (spherical mirror ˜ 1.5m2 and retina of 100 pixels) is presented for the Antarctic balloon-borne measurements of the CR spectrum. Long time winter flight make it possible to measure the spectrum above 1020 eV . Comparison with satellite and ISS projects of the nearest future show that the efficiency of this detector is sufficiently high. The energy threshold is less (˜ 1018 eV ). The accuracy of the energy definition is high as two methods are together the measurement of the EAS fluorescence track in the atmosphere and the measurement of the full flux of the EAS Cherenkov light.

  3. Limits on deeply penetrating particles in the 10(17) eV cosmic ray flux

    NASA Technical Reports Server (NTRS)

    Baltrusaitis, R. M.; Gerhardy, J. W.; Mizumoto, Y.; Cassiday, G. L.; Cooper, R.; Elbert, J. W.; Loh, P. R.; Sokolsky, P.; Sommers, P.; Steck, D.

    1985-01-01

    Deeply penetrating particles in the 10 to the 17th power eV cosmic ray flux were investigated. No such events were found in 8.2 x 10 to the 6th power sec of running time. Limits were set on the following: quark-matter in the primary cosmic ray flux; long-lived, weakly interacting particles produced in p-air collisions; the astrophysical neutrino flux. In particular, the neutrino flux limit at 10 to the 17th power eV implies that z, the red shift of maximum activity is 10 in the model of Hill and Schramm.

  4. Application features and considerations in advanced lead-acid and nickel/iron EV batteries

    SciTech Connect

    Miller, J.F.; Rajan, J.B.; Lee, T.S.; Christianson, C.C.; Hornstra, F.; Yao, N.P.

    1983-01-01

    In the development of advanced lead-acid and nickel/iron EV batteries, major efforts have focussed on improving specific energy, specific power, cycle life, and cost. Nonetheless, other battery characteristics related to application needs are also important features which must be considered during the battery development process. This paper describes various application features and improvements incorporated in these advanced lead-acid and nickel/iron EV batteries. Their volumetric energy density and packaging flexibility are presented: their charged-stand capabilities and energy efficiencies are reported; and development work on the safe control of battery off-gases and the implementation of single-point watering systems is discussed.

  5. Electron and positron scattering on rubidium at 200 eV

    SciTech Connect

    Chin, J. H.; Ratnavelu, K.; Zhou, Y.

    2014-03-05

    The recent implementation of the coupled-channels-optical method (CCOM) [1,2], in the study of the electron and positron-Rubidium(Rb) scattering at intermediate energies [3,4], shows that the continuum effect remains important as the energy increases, even to 100 eV. Here, we study the effect of the continuum in electron and positron scattering on Rb at an even higher energy namely 200 eV. The total, elastic and inelastic integral and differential cross sections are therefore calculated and compared to the available experimental [5] and theoretical data [6,7].

  6. EV-A71 vaccine licensure: a first step for multivalent enterovirus vaccine to control HFMD and other severe diseases.

    PubMed

    Mao, Qunying; Wang, Yiping; Bian, Lianlian; Xu, Miao; Liang, Zhenglun

    2016-01-01

    Enteroviruses (EVs) are the most common viral agents in humans. Although most infections are mild or asymptomatic, there is a wide spectrum of clinical manifestations that may be caused by EV infections with varying degrees of severity. Among these viruses, EV-A71 and coxsackievirus (CV) CV-A16 from group A EVs attract the most attention because they are responsible for hand, foot and mouth disease (HFMD). Other EV-A viruses such as CV-A6 and CV-A10 were also reported to cause HFMD outbreaks in several countries or regions. Group B EVs such as CV-B3, CV-B5 and echovirus 30 were reported to be the main pathogens responsible for myocarditis and encephalitis epidemics and were also detected in HFMD patients. Vaccines are the best tools to control infectious diseases. In December 2015, China's Food and Drug Administration approved two inactivated EV-A71 vaccines for preventing severe HFMD.The CV-A16 vaccine and the EV-A71-CV-A16 bivalent vaccine showed substantial efficacy against HFMD in pre-clinical animal models. Previously, research on EV-B group vaccines was mainly focused on CV-B3 vaccine development. Because the HFMD pathogen spectrum has changed, and the threat from EV-B virus-associated severe diseases has gradually increased, it is necessary to develop multivalent HFMD vaccines. This study summarizes the clinical symptoms of diseases caused by EVs, such as HFMD, myocarditis and encephalitis, and the related EV vaccine development progress. In conclusion, developing multivalent EV vaccines should be strongly recommended to prevent HFMD, myocarditis, encephalitis and other severe diseases. PMID:27436364

  7. Direct Measurement of the Mass Difference of 163Ho and 163Dy Solves the Q -Value Puzzle for the Neutrino Mass Determination

    NASA Astrophysics Data System (ADS)

    Eliseev, S.; Blaum, K.; Block, M.; Chenmarev, S.; Dorrer, H.; Düllmann, Ch. E.; Enss, C.; Filianin, P. E.; Gastaldo, L.; Goncharov, M.; Köster, U.; Lautenschläger, F.; Novikov, Yu. N.; Rischka, A.; Schüssler, R. X.; Schweikhard, L.; Türler, A.

    2015-08-01

    The atomic mass difference of 163 and 163Dy has been directly measured with the Penning-trap mass spectrometer SHIPTRAP applying the novel phase-imaging ion-cyclotron-resonance technique. Our measurement has solved the long-standing problem of large discrepancies in the Q value of the electron capture in 163Ho determined by different techniques. Our measured mass difference shifts the current Q value of 2555(16) eV evaluated in the Atomic Mass Evaluation 2012 [G. Audi et al., Chin. Phys. C 36, 1157 (2012)] by more than 7 σ to 2833 (30stat)(15sys) eV /c2 . With the new mass difference it will be possible, e.g., to reach in the first phase of the ECHo experiment a statistical sensitivity to the neutrino mass below 10 eV, which will reduce its present upper limit by more than an order of magnitude.

  8. Mentoring Undergraduates with Professional and Liberal Arts Goals: The Mass Communication Experience.

    ERIC Educational Resources Information Center

    Cohen, Jeremy

    2001-01-01

    Considers mentoring in mass communication and journalism programs, by which the dual objectives of professional and liberal arts education can be addressed by faculty recruited from the professions as well as from backgrounds of graduate education and research scholarship. (EV)

  9. Photoluminescence between 3.36 eV and 3.41 eV from GaN epitaxial layers

    SciTech Connect

    Seitz, R.; Gaspar, C.; Monteiro, T.; Pereira, E.; Poisson, M.A.; Beaumont, B.

    1999-07-01

    GaN, its alloys, QWs and MQWs have gained an important place among short-wavelength optical emitters and high temperature electronic devices. The performance of such devices is limited by the presence of native and impurity defects. The understanding of the optical properties of the basic material allows them to improve its quality and thus increase the performance of these materials. In non intentionally doped (nid) hexagonal good quality GaN layers grown on sapphire, 6H-SiC or Si, free exciton (FXC, FXB, FXA), donor bound exciton (DX), acceptor bound exciton (AX) and donor-acceptor pair (DAP) transitions have been reported by several authors. Besides these typical emissions, emission lines in the range 3.3--3.44 eV have been observed in nid and intentionally doped hexagonal GaN layers. However, the nature of these recombinations is not completely clarified. Some authors assigned them to a superposition of LO phonon assisted transitions of DX and FX, excitons bound to neutral donors with deeper donor levels, band to impurity transitions and/or free to bound emission involving oxygen, DAP transitions, shallow bound excitons of cubic phases, excitons bound to structural defects and Zn related recombinations. In this work the authors analyze the luminescence between 3.36 eV and 3.41 eV of nid hexagonal GaN samples grown on sapphire. They found sample dependent emission lines with no DAP behavior. From the data they are able to identify different kinds of recombination processes in the same spectral region.

  10. A relation between EL2 (Ec - 0.81 eV) and EL6 (Ec - 0.35 eV) in annealed HB-GaAs by hydrogen plasma exposure

    NASA Astrophysics Data System (ADS)

    Cho, Hoon Young; Kim, Eun Kyu; Min, Suk-Ki

    1989-10-01

    We present annealing and hydrogenation behaviors for EL2 (Ec-0.81 eV) and EL6 (Ec-0.35 eV) as dominant deep levels in GaAs. During rapid thermal annealing and the hydrogenation process, a relation has been identified between a midgap level group (the EL2 group) at 0.73, 0.81, and 0.87 eV, and a deep-level group (the EL6 group) at 0.27, 0.18, and 0.22 eV below the conduction band. We then discuss a relation between the two groups and their origins.

  11. What kind of charging infrastructure do Chevrolet Volts Drivers in The EV Project use?

    SciTech Connect

    John Smart

    2013-09-01

    This report summarizes key conclusions from analysis of data collected from Chevrolet Volts participating in The EV Project. Topics include how much Volt drivers charge at level 1 vs. level 2 rates and how much they charge at home vs. away from home.

  12. MEK1-ERKs signal cascade is required for the replication of Enterovirus 71 (EV71).

    PubMed

    Wang, Bo; Zhang, Hao; Zhu, Meng; Luo, Zhijun; Peng, Yihong

    2012-01-01

    The role of the MEK1-ERK signaling cascade in the replication cycle of Enterovirus 71 (EV71), the primary cause of hand, foot and mouth disease (HFMD), has been analyzed. In vitro infection with EV71 induced a biphasic activation of ERK. The two phases of activation appeared to be triggered by different mechanisms, with the first phase being activated by the binding of viral particles to the membrane receptor of host cells and the second probably being in response to the production of new virus particles. Inhibition of ERK activation by U0126 was found to severely impair virus production. A similar reduction in EV71 replication was also observed when MEK1 expression was subject to knockdown using specific siRNAs. By contrast knockdown of MEK2 expression showed that it was dispensable for virus replication cycle, despite both MEK isoforms being activated and translocated to the nucleus equally well in response to virus infection. Overall, this study suggests distinct functions of the two isoforms of MEK in EV71 replication cycle, with an essential role for MEK1 in stimulating the ERK signaling cascade to promote virus replication. Taken together with our previous work on herpes simplex virus type 2 (HSV2) this study highlights MEK1 as a potential broad antiviral molecular target. PMID:22101247

  13. How many electric miles do Nissan Leafs and Chevrolet Volts in The EV Project travel?

    SciTech Connect

    John Smart

    2014-05-01

    This paper presents travel statistics and metrics describing the driving behavior of Nissan Leaf and Chevrolet Volt drivers in the EV Project. It specifically quantifies the distance each group of vehicles drives each month. This paper will be published to INL's external website and will be accessible by the general public.

  14. On the Variation of Eta with Energy in the 100-1000 ev Region

    DOE R&D Accomplishments Database

    Wigner, E. P.

    1949-11-01

    Fluctuations in the fission yield in the 100- to 1000-ev region led to an investigation of the influencing variables. Changes in fission width from level to level and higher angular momentum phenomena are seen as possible explanations. (D.E.B.)

  15. Periodic gamma-ray emissions from Geminga at or = 10(12) eV

    NASA Technical Reports Server (NTRS)

    Kaul, R. K.; Rawat, H. S.; Sanecha, V. K.; Rannot, R. C.; Sapru, M.; Tickoo, A. K.; Qazi, R. A.; Bhat, C. L.; Razdan, H.; Tonwar, S. C.

    1985-01-01

    Analysis of data from an atmospheric Cerenkov telescope indicated the periodic emission of gamma rays of energy 10 to the 12th power eV, at 60.25 second period, from 2CG 195+4. The gamma ray flux at 99% confidence level is estimated to be 9.5 x 10 to 12 photons/sq cm/s.

  16. On galactic origin of cosmic rays with energy up to 10(19) eV

    NASA Technical Reports Server (NTRS)

    Mikhailov, A. A.; Efimov, N. N.

    1985-01-01

    The experimental data on ultrahigh energy cosmic ray anisotropy are considered. In supposed models of galactic magnetic field the main characteristics of expected anisotropy are estimated and are compared with the experimental data. It is shown that particles with energy up to 10 to the 19th power eV are of galactic origin.

  17. Arrival direction distribution of cosmic rays of energy 10 (18) eV

    NASA Technical Reports Server (NTRS)

    Reid, R. J. O.; Eames, P. V.; Lloyd-Evans, J.; Morello, C.; Watson, A. A.

    1985-01-01

    The Haverah Park air-shower experiment recorded over 8500 events with primary energy 10 to the 18th power eV between 1963 and 1983. An analysis of these events for anisotropies in celestial and galactic coordinates is reported. No very striking anisotropies are observed.

  18. Structural Studies of Potential 1 eV Solar Cell Materials

    SciTech Connect

    Norman, A.; Al-Jassim, M.; Friedman, D.; Geisz, J.; Olson, J.; Kurtz, S.

    2000-01-01

    Structural studies using transmission electron microscopy have been made on 1-eV band-gap materials, lattice-matched to GaAs and Ge substrates, grown by metal-organic vapor-phase epitaxy for use in multijunction, high-efficiency solar cells.

  19. What kind of charging infrastructure do Nissan Leaf drivers in The EV Project use?

    SciTech Connect

    Shawn Salisbury

    2014-09-01

    This document will describe the charging behavior of Nissan Leaf battery electric vehicles that were enrolled in the EV Project. It will include aggregated data from several thousand vehicles regarding time-of-day, power level, and location of charging and driving events. This document is a white paper that will be published on the INL AVTA website.

  20. Parity violation in {sup 232}Th neutron resonances above 250 eV

    SciTech Connect

    Sharapov, E. I.; Bowman, J. D.; Crawford, B. E.; Delheij, P. P. J.; Frankle, C. M.; Iinuma, M.; Knudson, J. N.; Lowie, L. Y.; Lynch, J. E.; Masaike, A.

    2000-02-01

    The analysis of parity nonconservation (PNC) measurements performed on {sup 232}Th by the TRIPLE Collaboration has been extended to include the neutron energy range of 250 to 1900 eV. Below 250 eV all ten statistically significant parity violations have the same sign. However, at higher energies PNC effects of both signs were observed in the transmission of longitudinally polarized neutrons through a thick thorium target. Although the limited experimental energy resolution precluded analysis in terms of the longitudinal asymmetry, parity violations were observed and the cross section differences for positive and negative neutron helicities were obtained. For comparison, a similar analysis was performed on the data below 250 eV, for which longitudinal asymmetries were obtained previously. For energies below 250 eV, the p-wave neutron strength functions for the J=1/2 and J=3/2 states were extracted: S{sub 1/2}{sup 1}=(1.68{+-}0.61)x10{sup -4} and S{sub 3/2}{sup 1}=(0.75{+-}0.18)x10{sup -4}. The data provide constraints on the properties of local doorway states proposed to explain the PNC sign effect in thorium. (c) 2000 The American Physical Society.

  1. Crystal structures of enterovirus 71 (EV71) recombinant virus particles provide insights into vaccine design.

    PubMed

    Lyu, Ke; Wang, Guang-Chuan; He, Ya-Ling; Han, Jian-Feng; Ye, Qing; Qin, Cheng-Feng; Chen, Rong

    2015-02-01

    Hand-foot-and-mouth disease (HFMD) remains a major health concern in the Asia-Pacific regions, and its major causative agents include human enterovirus 71 (EV71) and coxsackievirus A16. A desirable vaccine against HFMD would be multivalent and able to elicit protective responses against multiple HFMD causative agents. Previously, we have demonstrated that a thermostable recombinant EV71 vaccine candidate can be produced by the insertion of a foreign peptide into the BC loop of VP1 without affecting viral replication. Here we present crystal structures of two different naturally occurring empty particles, one from a clinical C4 strain EV71 and the other from its recombinant virus containing an insertion in the VP1 BC loop. Crystal structure analysis demonstrated that the inserted foreign peptide is well exposed on the particle surface without significant structural changes in the capsid. Importantly, such insertions do not seem to affect the virus uncoating process as illustrated by the conformational similarity between an uncoating intermediate of another recombinant virus and that of EV71. Especially, at least 18 residues from the N terminus of VP1 are transiently externalized. Altogether, our study provides insights into vaccine development against HFMD. PMID:25492868

  2. Dissociative Electron Attachment to Carbon Dioxide via the 8.2 eV Feshbach resonance

    SciTech Connect

    Slaughter, Dan; Adaniya, Hidihito; Rescigno, Tom; Haxton, Dan; Orel, Ann; McCurdy, Bill; Belkacem, Ali

    2011-08-17

    Momentum imaging experiments on dissociative electron attachment (DEA) to CO{sub 2} are combined with the results of ab initio calculations to provide a detailed and consistent picture of the dissociation dynamics through the 8.2 eV resonance, which is the major channel for DEA in CO{sub 2}. The present study resolves several puzzling misconceptions about this system.

  3. An EVS Clicker Based Hybrid Assessment to Engage Students with Marking Criteria

    ERIC Educational Resources Information Center

    Bennett, Steve; Barker, Trevor; Lilley, Mariana

    2014-01-01

    Over 4 iterations of a large course (>180 students) in introductory emedia design in a first year computer science course we have seen a year on year improvement. We believe this is due to the use of EVS clickers for feed-forward assessment: that is to say a method of getting the whole class to evaluate previous cohorts' submissions in public…

  4. Galaxy masses

    NASA Astrophysics Data System (ADS)

    Courteau, Stéphane; Cappellari, Michele; de Jong, Roelof S.; Dutton, Aaron A.; Emsellem, Eric; Hoekstra, Henk; Koopmans, L. V. E.; Mamon, Gary A.; Maraston, Claudia; Treu, Tommaso; Widrow, Lawrence M.

    2014-01-01

    Galaxy masses play a fundamental role in our understanding of structure formation models. This review addresses the variety and reliability of mass estimators that pertain to stars, gas, and dark matter. The different sections on masses from stellar populations, dynamical masses of gas-rich and gas-poor galaxies, with some attention paid to our Milky Way, and masses from weak and strong lensing methods all provide review material on galaxy masses in a self-consistent manner.

  5. Supernova 2010ev: A reddened high velocity gradient type Ia supernova

    NASA Astrophysics Data System (ADS)

    Gutiérrez, Claudia P.; González-Gaitán, Santiago; Folatelli, Gastón; Pignata, Giuliano; Anderson, Joseph P.; Hamuy, Mario; Morrell, Nidia; Stritzinger, Maximilian; Taubenberger, Stefan; Bufano, Filomena; Olivares E., Felipe; Haislip, Joshua B.; Reichart, Daniel E.

    2016-05-01

    Aims: We present and study the spectroscopic and photometric evolution of the type Ia supernova (SN Ia) 2010ev. Methods: We obtain and analyze multiband optical light curves and optical/near-infrared spectroscopy at low and medium resolution spanning -7 days to +300 days from the B-band maximum. Results: A photometric analysis shows that SN 2010ev is a SN Ia of normal brightness with a light-curve shape of Δm15(B) = 1.12 ± 0.02 and a stretch s = 0.94 ± 0.01 suffering significant reddening. From photometric and spectroscopic analysis, we deduce a color excess of E(B - V) = 0.25 ± 0.05 and a reddening law of Rv = 1.54 ± 0.65. Spectroscopically, SN 2010ev belongs to the broad-line SN Ia group, showing stronger than average Si iiλ6355 absorption features. We also find that SN 2010ev is a high velocity gradient SN with v˙Si = 164 ± 7 km s-1 d-1. The photometric and spectral comparison with other supernovae shows that SN 2010ev has similar colors and velocities to SN 2002bo and SN 2002dj. The analysis of the nebular spectra indicates that the [Fe ii]λ7155 and [Ni ii]λ7378 lines are redshifted, as expected for a high velocity gradient supernova. All these common intrinsic and extrinsic properties of the high velocity gradient (HVG) group are different from the low velocity gradient (LVG) normal SN Ia population and suggest significant variety in SN Ia explosions. This paper includes data gathered with the Du Pont Telescope at Las Campanas Observatory, Chile; and the Gemini Observatory, Cerro Pachon, Chile (Gemini Program GS-2010A-Q-14). Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile (ESO Programme 085.D-0577).

  6. Isotropy Constraints on Powerful Sources of Ultrahigh-energy Cosmic Rays at 1019 eV

    NASA Astrophysics Data System (ADS)

    Takami, Hajime; Murase, Kohta; Dermer, Charles D.

    2016-01-01

    Anisotropy in the arrival direction distribution of ultrahigh-energy cosmic rays (UHECRs) produced by powerful sources is numerically evaluated. We show that nondetection of significant anisotropy at ≈ {10}19 eV at present and in future experiments imposes general upper limits on UHECR proton luminosity of steady sources as a function of source redshifts. The upper limits constrain the existence of typical steady {10}19 eV UHECR sources in the local universe and limit their local density to ≳ {10}-3 Mpc {}-3, assuming average intergalactic magnetic fields less than {10}-9 G. This isotropy, being stronger than that measured at the highest energies, may indicate the transient generation of UHECRs. Our calculations are applied for extreme high-frequency-peaked BL Lacertae objects 1ES 0229+200, 1ES 1101-232, and 1ES 0347-121, to test the UHECR-induced cascade model, in which beamed UHECR protons generate TeV radiation in transit from sources. While the magnetic-field structure surrounding the sources affects the required absolute cosmic-ray luminosity of the blazars, the magnetic-field structure surrounding the Milky Way directly affects the observed anisotropy. If these magnetic fields are weak enough, significant UHECR anisotropy from these blazars is detectable by the Pierre Auger Observatory unless the maximum energy of UHECR protons is below 1019 eV. Furthermore, if these are the sources of UHECRs above 1019 eV, a local magnetic structure surrounding the Milky Way is needed to explain the observed isotropy at ˜ {10}19 eV, which may be incompatible with large magnetic structures around all galaxies for the UHECR-induced cascade model to work with reasonable jet powers.

  7. Control Strategies for Electric Vehicle (EV) Charging Using Renewables and Local Storage

    SciTech Connect

    Castello, Charles C; LaClair, Tim J; Maxey, L Curt

    2014-01-01

    The increase of electric vehicle (EV) and plug-in hybrid-electric vehicle (PHEV) adoption creates a need for more EV supply equipment (EVSE) infrastructure (i.e., EV chargers). The impact of EVSE installations could be significant due to limitations in the electric grid and potential demand charges for residential and commercial customers. The use of renewables (e.g., solar) and local storage (e.g., battery bank) can mitigate loads caused by EVSE on the electric grid. This would eliminate costly upgrades needed by utilities and decrease demand charges for consumers. This paper aims to explore control systems that mitigate the impact of EVSE on the electric grid using solar energy and battery banks. Three control systems are investigated and compared in this study. The first control system discharges the battery bank at a constant rate during specific times of the day based on historical data. The second discharges the battery bank based on the number of EVs charging (linear) and the amount of solar energy being generated. The third discharges the battery bank based on a sigmoid function (non-linear) in response to the number of EVs charging, and also takes into consideration the amount of renewables being generated. The first and second control systems recharge the battery bank at night when demand charges are lowest. The third recharges the battery bank at night and during times of the day when there is an excess of solar. Experiments are conducted using data from a private site that has 25 solar-assisted charging stations at Oak Ridge National Laboratory (ORNL) in Oak Ridge, TN and 4 at a public site in Nashville, TN. Results indicate the third control system having better performance, negating up to 71% of EVSE load, compared with the second control system (up to 61%) and the first control system (up to 58%).

  8. Supernova 2010ev: A reddened high velocity gradient type Ia supernova

    NASA Astrophysics Data System (ADS)

    Gutiérrez, Claudia P.; González-Gaitán, Santiago; Folatelli, Gastón; Pignata, Giuliano; Anderson, Joseph P.; Hamuy, Mario; Morrell, Nidia; Stritzinger, Maximilian; Taubenberger, Stefan; Bufano, Filomena; Olivares E., Felipe; Haislip, Joshua B.; Reichart, Daniel E.

    2016-04-01

    Aims: We present and study the spectroscopic and photometric evolution of the type Ia supernova (SN Ia) 2010ev. Methods: We obtain and analyze multiband optical light curves and optical/near-infrared spectroscopy at low and medium resolution spanning -7 days to +300 days from the B-band maximum. Results: A photometric analysis shows that SN 2010ev is a SN Ia of normal brightness with a light-curve shape of Δm15(B) = 1.12 ± 0.02 and a stretch s = 0.94 ± 0.01 suffering significant reddening. From photometric and spectroscopic analysis, we deduce a color excess of E(B - V) = 0.25 ± 0.05 and a reddening law of Rv = 1.54 ± 0.65. Spectroscopically, SN 2010ev belongs to the broad-line SN Ia group, showing stronger than average Si iiλ6355 absorption features. We also find that SN 2010ev is a high velocity gradient SN with v˙Si = 164 ± 7 km s-1 d-1. The photometric and spectral comparison with other supernovae shows that SN 2010ev has similar colors and velocities to SN 2002bo and SN 2002dj. The analysis of the nebular spectra indicates that the [Fe ii]λ7155 and [Ni ii]λ7378 lines are redshifted, as expected for a high velocity gradient supernova. All these common intrinsic and extrinsic properties of the high velocity gradient (HVG) group are different from the low velocity gradient (LVG) normal SN Ia population and suggest significant variety in SN Ia explosions. This paper includes data gathered with the Du Pont Telescope at Las Campanas Observatory, Chile; and the Gemini Observatory, Cerro Pachon, Chile (Gemini Program GS-2010A-Q-14). Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile (ESO Programme 085.D-0577).

  9. Monoclonal neutralizing antibodies against EV71 screened from mice immunized with yeast-produced virus-like particles.

    PubMed

    Lin, Tao; Xianyu, Lingzhi; Lyu, Songya

    2015-06-01

    Periodic outbreaks of hand, foot and mouth disease (HFMD) occur in children under 5 years old, and can cause death in some cases. The C4 strain of enterovirus 71 (EV71) is the main pathogen that causes HFMD in China. Although no drugs against EV71 are available, some studies have shown that candidate vaccines or viral capsid proteins can produce anti-EV71 immunity. In this study, female BABL/c mice (6-8 weeks old) were immunized with virus-like particles (VLPs) of EV71 produced in yeast to screen for anti-EV71 antibodies. Two hybridomas that could produce neutralizing antibodies against EV71 were obtained. Both neutralizing mAbs (D4 and G12) were confirmed to bind the VP1 capsid protein of EV71, and could protect >95% cells from 100 TCID50 EV71 infection at 25 µg/mL solution (lowest concentration). Those two neutralizing mAbs identified in the study may be promising candidates in development for mAbs to treat EV71 infection, and utilized as suitable reagents for use in diagnostic tests and biological studies. PMID:26040893

  10. Time-Resolved UV-Pump (4.8eV) and Vacuum-UV (8eV) Probe Experiments of Neutral Excited State Dynamics

    NASA Astrophysics Data System (ADS)

    Horton, Spencer; Liu, Yusong; Matsika, Spiridoula; Weinacht, Thomas

    2016-05-01

    Excited state dynamics in polyatomic molecules involve a rich mixture of internal conversion, intersystem crossing, isomerization, and dissociation. Probing these dynamics with ultrafast laser pulses poses a number of challenges, in terms of both the execution of the measurements and their interpretation. We have developed an apparatus for probing excited state dynamics using a 260nm UV-pump pulse and a 156nm Vacuum-UV (VUV) probe pulse. For many systems of interest, an 8eV probe pulse can ionize the molecule from essentially any position along the excited state potential, while not having a background ionization yield from the ground state. Furthermore, given the perturbative interaction of each pulse with the molecule, it is possible interpret and model the experimental results with greater ease and confidence than more complicated probe interactions such as strong field ionization. We compare UV-IR strong-field ionization pump-probe experiments previously conducted directly with our 8eV probing and explore the differences between the two.

  11. Mass dependence of nitride sputtering

    NASA Astrophysics Data System (ADS)

    Elovikov, S. S.; Khrustachev, I. K.; Mosunov, A. S.; Yurasova, V. E.

    2003-08-01

    A molecular dynamics simulation was performed to study the sputtering yield Y for BN, AlN and GaN polycrystals of wurtzite structure as a function of the masses m 1 of bombarding ions with energies from 200 to 2000 eV. A nonmonotonic behavior of the Y ( m 1 ) curve was obtained for the irradiation by low-energy ions, the curve having a maximum with a position being dependent on m 2 / m 1 ( m 2 is the average mass of atoms in a compound). For AlN and GaN the maximum was observed at m 2 / m 1 = 2, and for BN at m 2 / m 1 = 1. The effect of the mass of bombarding ions on the mean energies and energy spectra of sputtered particles, the depth of sputtering origin, and the generation of emitted atoms for nitrides was also investigated and discussed.

  12. Impurity characterization of solar wind collectors for the genesis discovery mission by resonance ionization mass spectrometry.

    SciTech Connect

    Calaway, W. F.

    1999-02-01

    NASA's Genesis Discovery Mission is designed to collect solar matter and return it to earth for analysis. The mission consists of launching a spacecraft that carries high purity collector materials, inserting the spacecraft into a halo orbit about the L1 sun-earth libration point, exposing the collectors to the solar wind for two years, and then returning the collectors to earth. The collectors will then be made available for analysis by various methods to determine the elemental and isotopic abundance of the solar wind. In preparation for this mission, potential collector materials are being characterized to determine baseline impurity levels and to assess detection limits for various analysis techniques. As part of the effort, potential solar wind collector materials have been analyzed using resonance ionization mass spectrometry (RIMS). RIMS is a particularly sensitivity variation of secondary neutral mass spectrometry that employs resonantly enhanced multiphoton ionization (REMPI) to selectively postionize an element of interest, and thus discriminates between low levels of that element and the bulk material. The high sensitivity and selectivity of RIMS allow detection of very low concentrations while consuming only small amounts of sample. Thus, RIMS is well suited for detection of many heavy elements in the solar wind, since metals heavier than Fe are expected to range in concentrations from 1 ppm to 0.2 ppt. In addition, RIMS will be able to determine concentration profiles as a function of depth for these implanted solar wind elements effectively separating them from terrestrial contaminants. RIMS analyses to determine Ti concentrations in Si and Ge samples have been measured. Results indicate that the detection limit for RIMS analysis of Ti is below 100 ppt for 10{sup 6} averages. Background analyses of the mass spectra indicate that detection limits for heavier elements will be similar. Furthermore, detection limits near 1 ppt are possible with higher

  13. Neutrino masses and proton decay in SO(10)

    NASA Astrophysics Data System (ADS)

    Abud, M.; Buccella, F.; Falcone, D.

    2012-10-01

    We consider the constraints on SO(10) unified models coming from the lower limits on proton lifetime and on the scale of B-L symmetry breaking within the framework of the seesaw model for neutrino masses. By upgrading a triangular relationship for the inverse of νL Majorana masses to the experimental situation with nonmaximal θ23 and nonvanishing θ13, we get for the sum of νL masses the upper limit 0.16 eV.

  14. Cosmological neutrino mass detection: The Best probe of neutrino lifetime

    SciTech Connect

    Serpico, Pasquale D.; /Fermilab

    2007-01-01

    Future cosmological data may be sensitive to the effects of a finite sum of neutrino masses even as small as {approx}0.06 eV, the lower limit guaranteed by neutrino oscillation experiments. We show that a cosmological detection of neutrino mass at that level would improve by many orders of magnitude the existing limits on neutrino lifetime, and as a consequence on neutrino secret interactions with (quasi-)massless particles as in majoron models. On the other hand, neutrino decay may provide a way-out to explain a discrepancy {approx}< 0.1 eV between cosmic neutrino bounds and Lab data.

  15. Cosmological Neutrino Mass Detection: The Best Probe of Neutrino Lifetime

    SciTech Connect

    Serpico, Pasquale D.

    2007-04-27

    Future cosmological data may be sensitive to the effects of a finite sum of neutrino masses even as small as {approx}0.06 eV, the lower limit guaranteed by neutrino oscillation experiments. We show that a cosmological detection of neutrino mass at that level would improve by many orders of magnitude the existing limits on neutrino lifetime, and as a consequence, on neutrino secret interactions with (quasi)massless particles as in Majoron models. On the other hand, neutrino decay may provide a way out to explain a discrepancy < or approx. 0.1 eV between cosmic neutrino bounds and lab data.

  16. Negative mass

    NASA Astrophysics Data System (ADS)

    Hammond, Richard T.

    2015-03-01

    Some physical aspects of negative mass are examined. Several unusual properties, such as the ability of negative mass to penetrate any armor, are analysed. Other surprising effects include the bizarre system of negative mass chasing positive mass, naked singularities and the violation of cosmic censorship, wormholes, and quantum mechanical results as well. In addition, a brief look into the implications for strings is given.

  17. A new measurement of the cosmic ray energy spectrum between 3 x 10 to the 15th power eV and 3 x 10 to the 16th power eV

    NASA Technical Reports Server (NTRS)

    Gregory, A. G.; Patterson, J. R.; Protheroe, R. J.

    1985-01-01

    A new Cerenkov photon density spectrum measurement is reported. The derivation of the primary cosmic ray energy spectrum for energies from 3x10 to the 15th power eV to 3x10 to the 16th power eV are presented.

  18. Stable SUSY breaking model with O(10) eV gravitino from combined D-term gauge mediation and U(1)' mediation

    SciTech Connect

    Nakayama, Yu; Nakayama, Yu

    2007-12-17

    We show a calculable example of stable supersymmetry (SUSY) breaking modelswith O(10) eV gravitino mass based on the combination of D-term gauge mediationand U(1)' mediation. A potential problem of the negative mass squared for theSUSY standard model (SSM) sfermions in the D-term gauge mediation is solvedby the contribution from the U(1)' mediation. On the other hand, the splittingbetween the SSM gauginos and sfermions in the U(1)' mediation iscircumvented bythe contributions from the D-term gauge mediation. Since the U(1)' mediation doesnot introduce any new SUSY vacua, we achieve a completely stable model underthermal effects. Our model, therefore, has no cosmological difficulty.

  19. Single and double photoionization of aromatics: A comparative study of C6H6 isomers between 25 and 70 eV

    NASA Astrophysics Data System (ADS)

    Braitbart, Ori; Tobita, Seiji; Leach, Sydney; Roy, Pascale; Nenner, Irène

    1992-07-01

    Monochromatized synchrotron radiation from the LURE-ACO storage ring was used to excite and ionize three C6H6 isomers in the 25-70 eV photon energy range. The compounds studied were the cyclic species benzene and the two-open chain molecules 1,5-hexadiyne and 2,4-hexadiyne. Four types of measurements are described which involve a high resolution reflectron TOF mass analyzer. Half-integer and 13C isotope mass peaks in the PEPICO TOF-MS provided information on parent and fragment dications. From the PEPIPICO spectra, the correlated times of flight values for the two monocations originating in the Coulomb dissociation of a dication gave information on the principal fragmentation pathways. Similarities and differences in the various spectra provide insight into dynamic processes, including structural rearrangements, which follow single and double ionization in these species, but require more analysis and also modelization of energy deposition for further clarification.

  20. Measurement of ion species produced due to bombardment of 450 eV N2+ ions with hydrocarbons-covered surface of tungsten: Formation of tungsten nitride

    NASA Astrophysics Data System (ADS)

    Kumar, S.; Bhatt, P.; Kumar, A.; Singh, B. K.; Singh, B.; Prajapati, S.; Shanker, R.

    2016-08-01

    A laboratory experiment has been performed to study the ions that are produced due to collisions of 450 eV N2+ ions with a hydrocarbons-covered surface of polycrystalline tungsten at room temperature. Using a TOF mass spectrometry technique, the product ions formed in these collisions have been detected, identified and analyzed. Different ion-surface reaction processes, namely, neutralization, reflection, surface induced dissociation, surface induced chemical reactions and desorption are observed and discussed. Apart from the presence of desorbed aliphatic hydrocarbon and other ions, the mass spectra obtained from the considered collisions show the formation and sputtering of tungsten nitride (WN). A layer of WN on tungsten surface is known to decrease the sputtering of bulk tungsten in fusion devices more effectively than when the tungsten is bombarded with other seeding gases (He, Ar). It is further noted that there is a negligible diffusion of N in the bulk tungsten at room temperature.

  1. Detection of native protein ions in aqueous solution under ambient conditions by electrospray laser desorption/ionization mass spectrometry.

    PubMed

    Shiea, Jentaie; Yuan, Cheng-Hui; Huang, Min-Zong; Cheng, Sy-Chyi; Ma, Ya-Lin; Tseng, Wei-Lung; Chang, Hui-Chiu; Hung, Wen-Chun

    2008-07-01

    Liquid electrospray laser desorption/ionization (ELDI) mass spectrometry allows desorption and ionization of proteins directly from aqueous solutions and biological fluids under ambient conditions. Native protein ions such as those of myoglobin, cytochrome c, and hemoglobin were obtained. A droplet (ca. 5 microL) containing the protein molecules and micrometer-sized particles (e.g., carbon graphite powder) is irradiated with a pulsed UV laser. The laser energy adsorbed by the inert particles is transferred to the surrounding solvent and protein molecules, leading to their desorption; the desorbed gaseous molecules are then postionized within an electrospray (ESI) plume to generate the ESI-like protein ions. With the use of this technique, we detected only the protonated protein ions in various biological fluids (including human tears, cow milk, serum, and bacterial extracts) without interference from their corresponding sodiated or potassiated adduct ions. In addition, we rapidly quantified the levels of glycosylated hemoglobin present in drops of whole blood obtained from diabetic patients without the need of sample pretreatment. PMID:18510347

  2. Compact Two-step Laser Time-of-Flight Mass Spectrometer for in Situ Analyses of Aromatic Organics on Planetary Missions

    NASA Technical Reports Server (NTRS)

    Getty, Stephanie; Brickerhoff, William; Cornish, Timothy; Ecelberger, Scott; Floyd, Melissa

    2012-01-01

    RATIONALE A miniature time-of-flight mass spectrometer has been adapted to demonstrate two-step laser desorption-ionization (LOI) in a compact instrument package for enhanced organics detection. Two-step LDI decouples the desorption and ionization processes, relative to traditional laser ionization-desorption, in order to produce low-fragmentation conditions for complex organic analytes. Tuning UV ionization laser energy allowed control ofthe degree of fragmentation, which may enable better identification of constituent species. METHODS A reflectron time-of-flight mass spectrometer prototype measuring 20 cm in length was adapted to a two-laser configuration, with IR (1064 nm) desorption followed by UV (266 nm) postionization. A relatively low ion extraction voltage of 5 kV was applied at the sample inlet. Instrument capabilities and performance were demonstrated with analysis of a model polycyclic aromatic hydrocarbon, representing a class of compounds important to the fields of Earth and planetary science. RESULTS L2MS analysis of a model PAH standard, pyrene, has been demonstrated, including parent mass identification and the onset o(tunable fragmentation as a function of ionizing laser energy. Mass resolution m/llm = 380 at full width at half-maximum was achieved which is notable for gas-phase ionization of desorbed neutrals in a highly-compact mass analyzer. CONCLUSIONS Achieving two-step laser mass spectrometry (L2MS) in a highly-miniature instrument enables a powerful approach to the detection and characterization of aromatic organics in remote terrestrial and planetary applications. Tunable detection of parent and fragment ions with high mass resolution, diagnostic of molecular structure, is possible on such a compact L2MS instrument. Selectivity of L2MS against low-mass inorganic salt interferences is a key advantage when working with unprocessed, natural samples, and a mechanism for the observed selectivity is presented.

  3. Elevated expression of circulating miR876-5p is a specific response to severe EV71 infections

    PubMed Central

    Wang, Robert Y. L.; Weng, Kuo-Feng; Huang, Yhu-Chering; Chen, Chih-Jung

    2016-01-01

    Human enterovirus 71 (EV71) is a major causative agent of hand, foot, and, mouth disease, accounting for more than 65% of recent outbreaks. Following enteroviral infection, the host responses are crucial indicators for the development of a diagnosis regarding the clinical severity of EV71 infections. In this study, we implemented NanoString nCounter technology to characterize the responses of serum microRNA (miRNA) profiles to various EV71 infection diseases. Upon EV71 infection, 44 miRNAs were observed in patients with EV71 infections, with at least a 2-fold elevation and 133 miRNAs with a 2-fold reduction compared with the same miRNAs in healthy controls. Further detailed work with miR876-5p, a 9.5-fold change of upregulated miR-876-5p expression was observed in cases with severe EV71 symptoms, revealed that in vitro and in vivo knockdown of miR876-5p reduced viral RNA in cultured cells, and attenuated the severity of symptoms in EV71-infected mice. Altogether, we demonstrated that the elevated expression of circulating miR876-5p is a specific response to severe EV71 infections. PMID:27052555

  4. Elevated expression of circulating miR876-5p is a specific response to severe EV71 infections.

    PubMed

    Wang, Robert Y L; Weng, Kuo-Feng; Huang, Yhu-Chering; Chen, Chih-Jung

    2016-01-01

    Human enterovirus 71 (EV71) is a major causative agent of hand, foot, and, mouth disease, accounting for more than 65% of recent outbreaks. Following enteroviral infection, the host responses are crucial indicators for the development of a diagnosis regarding the clinical severity of EV71 infections. In this study, we implemented NanoString nCounter technology to characterize the responses of serum microRNA (miRNA) profiles to various EV71 infection diseases. Upon EV71 infection, 44 miRNAs were observed in patients with EV71 infections, with at least a 2-fold elevation and 133 miRNAs with a 2-fold reduction compared with the same miRNAs in healthy controls. Further detailed work with miR876-5p, a 9.5-fold change of upregulated miR-876-5p expression was observed in cases with severe EV71 symptoms, revealed that in vitro and in vivo knockdown of miR876-5p reduced viral RNA in cultured cells, and attenuated the severity of symptoms in EV71-infected mice. Altogether, we demonstrated that the elevated expression of circulating miR876-5p is a specific response to severe EV71 infections. PMID:27052555

  5. Absolute total cross sections for the scattering of 2-18-eV electrons by cesium atoms

    NASA Astrophysics Data System (ADS)

    Jaduszliwer, B.; Chan, Y. C.

    1992-01-01

    Absolute total cross sections for the scattering of electrons by cesium atoms between 2 and 18 eV have been measured using the atomic-recoil technique in the scattering-out mode. Our results are somewhat lower than those of Visconti, Slevin, and Rubin [Phys. Rev. A 3, 1310 (1971)] above 2 eV.

  6. Different EV enrichment methods suitable for clinical settings yield different subpopulations of urinary extracellular vesicles from human samples

    PubMed Central

    Royo, Felix; Zuñiga-Garcia, Patricia; Sanchez-Mosquera, Pilar; Egia, Ainara; Perez, Amparo; Loizaga, Ana; Arceo, Raquel; Lacasa, Isabel; Rabade, Ainara; Arrieta, Edurne; Bilbao, Roberto; Unda, Miguel; Carracedo, Arkaitz; Falcon-Perez, Juan M.

    2016-01-01

    Urine sample analysis is irreplaceable as a non-invasive method for disease diagnosis and follow-up. However, in urine samples, non-degraded protein and RNA may be only found in urinary extracellular vesicles (uEVs). In recent years, various methods of uEV enrichment using low volumes of urine and unsophisticated equipment have been developed, with variable success. We compared the results of the differential ultracentrifugation procedure with 4 of these methods. The methods tested were a lectin-based purification, Exoquick (System Biosciences), Total Exosome Isolation from Invitrogen and an in-house modified procedure employing the Exosomal RNA Kit from Norgen Biotek Corp. The analysis of selected gene transcripts and protein markers of extracellular vesicles (EVs) revealed that each method isolates a different mixture of uEV protein markers. In our conditions, the extraction with Norgen's reagent achieved the best performance in terms of gene transcript and protein detection and reproducibility. By using this method, we were able to detect alterations of EVs protein markers in urine samples from prostate cancer adenoma patients. Taken together, our results show that the isolation of uEVs is feasible from small volumes of urine and avoiding ultracentrifugation, making easier the analysis in a clinical facility. However, caution should be taken in the selection of the enrichment method since they have a differential affinity for protein uEVs markers and by extension for different subpopulation of EVs. PMID:26895490

  7. Opacity Studies of Iron in the 15-30eV Temperature Range

    NASA Astrophysics Data System (ADS)

    Chenais-Popovics, Claude; Merdji, Hamed; Missalla, Thomas; Gilleron, Franck; Gauthier, Jean-Claude; Blenski, Thomas; Perrot, François; Klapisch, Marcel; Bauche-Arnoult, Claire; Bauche, Jacques; Bachelier, Annik; Eidmann, Klaus

    2000-04-01

    Absorption of the 2p-3d transitions of iron has been measured using point projection spectroscopy. Thin C tamped Fe foils were heated around 20 eV by X-rays generated in gold spherical hohlraums irradiated by the high-power laser ASTERIX IV. Absorption of Fe V to Fe X has been observed in the spectral vicinity of 730 eV (17 Å). The Ag backlighter source and absorbed spectra were recorded on the same shot by a TlAP crystal spectrograph. The experimental spectra have been reproduced by the two superconfiguration local thermodynamic equilibrium codes SCO and STA. Detailed statistical calculations of the different ionic structures have also been performed with the Spin Orbit Split Arrays method, allowing the determination of ion populations. The electron temperature and average ionization obtained by fitting the experiment with the different calculations were compared with radiative hydrodynamic simulations.

  8. Multipole character of the proposed 220 eV transition in [sup 229]Pa

    SciTech Connect

    Dragoun, O.; Rysavy, M. ); Guenther, C. )

    1993-02-01

    Internal conversion coefficients (ICC's) have been calculated for protactinium and transition energies between 170 eV and 10 keV. The ICC's for [ital E]1 multipolarity show an unusual behavior, which cannot be approximated by an exponential dependence on the transition energy, whereas the ICC's for [ital M]1 and [ital E]2 multipolarities closely follow such a dependence. Using the newly calculated ICC's the unusually strong enhancement'' of a possible 220 eV [ital E]1 transition in [sup 229]Pa proposed earlier is reduced by a factor of [similar to]5, yielding an induced electric dipole moment similar to that observed in the neighboring octupole-deformed isotopes.

  9. Elastic electron scattering in krypton in the energy range from 5 to 10 eV

    SciTech Connect

    Linert, Ireneusz; Mielewska, Brygida; Zubek, Mariusz; King, George C.

    2010-01-15

    Differential cross sections for elastic electron scattering in krypton have been measured at the energies of 5,7.5, and 10 eV over the scattering angle range from 30 deg. to 180 deg. The measurements for backward scattering employed the magnetic angle-changing technique. These differential cross sections have been integrated to yield the elastic integral and momentum transfer cross sections at the above energies. These new results are compared with the most recent measurements and calculations of the respective cross sections in krypton. The dependence of the differential cross sections on atomic polarizability of the heavier rare gas atoms argon, krypton, and xenon has also been investigated over the electron energy range 5-30 eV and for forward, backward, and intermediate scattering angles.

  10. Assessment of EV batteries and application to R and D planning

    NASA Astrophysics Data System (ADS)

    Henriksen, Gary L.; Patil, Pandit G.; Ratner, Elliot Z.; Warde, Charles J.

    1989-03-01

    To guide future EV battery R and D programs, the U.S. Department of Energy (DOE) commissioned a comprehensive assessment of secondary battery technologies. A total of 67 battery developers---from the United States, Canada, Europe, Asia, and Africa---were solicited to submit battery design concepts for an Improved Dual-Shaft Electric Propulsion (IDSEP) van. A team of 10 consultants and 7 representatives from DOE laboratories evaluated 42 developer responses and consultant-prepared designs. Using six criteria---five technical/economic criteria and a maturity/technical barriers criterion---the assessment identified 12 most-promising batteries. Employing a generic EV-battery development-system framework, the assessment results are being used to formulate multi-year R and D plans and schedules for the most-promising developmental batteries.

  11. Intense X-ray flares from active stellar systems - EV Lacertae and HD 8357

    NASA Technical Reports Server (NTRS)

    Ambruster, C.; Snyder, W. A.; Wood, K. S.

    1984-01-01

    The HEAO A-1 Sky Survey Experiment included X-ray data used to define light curves for the flare star EV Lac and for X-ray flares observed in the binary system HD 8357. The data were taken during flare events and were detailed enough to calculate the flare rates and flaring luminosities. The peak luminosities during flares were several times the luminosities in normal X-ray flares emitted by the objects. Peak luminosities reached 30-50 times the normal variations and were associated with an order of magnitude increase in energy output. EV Lac was sufficiently active to be recommended for inclusion in future X-ray monitoring programs.

  12. The Roll-over of Heliospheric Neutral Hydrogen below 100 eV: Observations and Implications

    NASA Astrophysics Data System (ADS)

    Galli, A.; Wurz, P.; Schwadron, N. A.; Kucharek, H.; Möbius, E.; Bzowski, M.; Sokół, J. M.; Kubiak, M. A.; Funsten, H. O.; Fuselier, S. A.; McComas, D. J.

    2016-04-01

    We present an improved analysis of the energy spectrum of energetic neutral hydrogen from the heliosheath observed with the IBEX-Lo sensor on the Interstellar Boundary EXplorer from the years 2009 to 2012. This analysis allows us to study the lowest energies between 10 and 100 eV although various background sources are more intense than the targeted signal over broad areas of the sky. The results improve our knowledge of the interaction region between our heliosphere and the interstellar plasma because these neutral atoms are direct messengers from the low-energy plasma in the heliosheath. We find a roll-over of the energy spectrum below 100 eV, which has major implications for the pressure balance of the plasma in the inner heliosheath. The results can also be compared directly with in situ observations of the Voyager 1 and 2 spacecraft.

  13. Traction Slip Ratio Control Based on Fuzzy DSMC for Independent AWD EV

    NASA Astrophysics Data System (ADS)

    Zou, Guangcai; Luo, Yugong; Li, Keqiang

    A traction slip ratio control method using fuzzy dynamical sliding mode strategy (Fuzzy DSMC) is proposed to reduce the slip ratio oscillations in the independent AWD EV traction control. The slip ratios are also accurately estimated in a new way to support this control process. Firstly in this control method, the fuzzy logic method is applied respectively to regulate the switching surface and the reaching law of DSMC with the estimated slip ratios, which are used to weaken the chattering and improve the convergence rate to some extent. Furthermore the control structure of DSMC is designed to obtain the smooth torque outputs from all independent traction motors, which are implemented in the anti-skid control for EV in the end. The mathematics analysis for the controller parameters choosing and simulation experiments show that the method can greatly avoid the drawback of control chattering occurred in the classical sliding mode control. Moreover, the robustness of systems for parameter uncertainties is also guaranteed.

  14. Compact time-of-flight mass spectrometer

    SciTech Connect

    Belov, A.S.; Kubalov, S.A.; Kuzik, V.F.; Yakushev, V.P.

    1986-02-01

    This paper describes a time-of-flight mass spectrometer developed for measuring the parameters of a pulsed hydrogen beam. The duration of an electron-beam current pulse in the ionizer of the mass spectrometer can be varied within 2-20 usec, the pulse electron current is 0.6 mA, and the electron energy is 250 eV. The time resolution of the mass spectrometer is determined by the repetition period of the electron-beam current pulses and is 40 usec. The mass spectrometer has 100% transmission in the direction of motion of molecular-beam particles. The dimension of the mass spectrometer is 7 cm in this direction. The mass resolution is sufficient for determination of the composition of the hydrogen beam.

  15. Measurement of the cosmic-ray energy spectrum above 1016 eV with the LOFAR Radboud Air Shower Array

    NASA Astrophysics Data System (ADS)

    Thoudam, S.; Buitink, S.; Corstanje, A.; Enriquez, J. E.; Falcke, H.; Hörandel, J. R.; Nelles, A.; Rachen, J. P.; Rossetto, L.; Schellart, P.; Scholten, O.; ter Veen, S.; Trinh, T. N. G.; van Kessel, L.

    2016-01-01

    The energy reconstruction of extensive air showers measured with the LOFAR Radboud Air Shower Array (LORA) is presented in detail. LORA is a particle detector array located in the center of the LOFAR radio telescope in the Netherlands. The aim of this work is to provide an accurate and independent energy measurement for the air showers measured through their radio signal with the LOFAR antennas. The energy reconstruction is performed using a parameterized relation between the measured shower size and the cosmic-ray energy obtained from air shower simulations. In order to illustrate the capabilities of LORA, the all-particle cosmic-ray energy spectrum has been reconstructed, assuming that cosmic rays are composed only of protons or iron nuclei in the energy range between ˜2 × 1016 and 2 × 1018 eV. The results are compatible with literature values and a changing mass composition in the transition region from a Galactic to an extragalactic origin of cosmic rays.

  16. Rydberg and valence state excitation dynamics: a velocity map imaging study involving the E-V state interaction in HBr.

    PubMed

    Zaouris, Dimitris; Kartakoullis, Andreas; Glodic, Pavle; Samartzis, Peter C; Rafn Hróðmarsson, Helgi; Kvaran, Ágúst

    2015-04-28

    Photoexcitation dynamics of the E((1)Σ(+)) (v' = 0) Rydberg state and the V((1)Σ(+)) (v') ion-pair vibrational states of HBr are investigated by velocity map imaging (VMI). H(+) photoions, produced through a number of vibrational and rotational levels of the two states were imaged and kinetic energy release (KER) and angular distributions were extracted from the data. In agreement with previous work, we found the photodissociation channels forming H*(n = 2) + Br((2)P3/2)/Br*((2)P1/2) to be dominant. Autoionization pathways leading to H(+) + Br((2)P3/2)/Br*((2)P1/2) via either HBr(+)((2)Π3/2) or HBr(+)*((2)Π1/2) formation were also present. The analysis of KER and angular distributions and comparison with rotationally and mass resolved resonance enhanced multiphoton ionization (REMPI) spectra revealed the excitation transition mechanisms and characteristics of states involved as well as the involvement of the E-V state interactions and their v' and J' dependence. PMID:25801122

  17. Equal energy sharing double photoionization of the helium atom at 20 eV and 40 eV above threshold

    NASA Astrophysics Data System (ADS)

    Das, J. N.; Chakrabarti, K.; Paul, S.

    2003-10-01

    In this Letter we present triple differential cross sections for equal energy sharing kinematics for double photoionization of the helium atom at 20 and 40 eV above threshold in the framework of the hyperspherical partial wave theory. This supplements our earlier work [J. Phys. B: At. Mol. Opt. Phys. 36 (2003) 2707] in which we were successful in showing fully, gauge independence of the results in our formalism. Also in this Letter we treat cases in which the Stokes parameter S1<1 so that partial polarization of the photon source is also taken into account. Agreement in shape with the convergent close coupling [A.S. Kheifets, 2003, private communication; H. Bräuning, et al., J. Phys. B: At. Mol. Opt. Phys. 31 (1998) 5149] calculation and the experiments appears to be excellent.

  18. High-kinetic-energy photoemission spectroscopy of Ni at 1s : 6-eV satellite at 4 eV

    NASA Astrophysics Data System (ADS)

    Karis, O.; Svensson, S.; Rusz, J.; Oppeneer, P. M.; Gorgoi, M.; Schäfers, F.; Braun, W.; Eberhardt, W.; Mårtensson, N.

    2008-12-01

    Electron correlations are responsible for many profound phenomena in solid-state physics. A classical example is the 6-eV satellite in the photoelectron spectrum of Ni. Until now the satellite structure has only been investigated at the L shell and more shallow levels. Here we report a high-kinetic-energy photoemission spectroscopy (HIKE) investigation of Ni metal. We present 1s and 2p photoelectron spectra, obtained using excitation energies up to 12.6 keV. Our investigation demonstrates that the energy position of the satellite relative to the main line is different for the 1s and the 2p levels. In combination with electronic structure calculations, we show that this energy shift is attributed to unique differences in the core-valence coupling for the K and L2,3 shells in 3d transition metals, resulting in different screening of the core holes.

  19. NREL's PHEV/EV Li-Ion Battery Secondary-Use Project

    SciTech Connect

    Newbauer, J.; Pesaran, A.

    2010-06-01

    Accelerated development and market penetration of plug-in hybrid electric vehicles (PHEVs) and electric vehicles (EVs) is restricted at present by the high cost of lithium-ion (Li-ion) batteries. One way to address this problem is to recover a fraction of the Li-ion battery's cost via reuse in other applications after it is retired from service in the vehicle, when the battery may still have sufficient performance to meet the requirements of other energy storage applications.

  20. EVS vs TIPS shunt for gastric variceal bleeding in patients with cirrhosis: A meta-analysis

    PubMed Central

    Bai, Ming; Qi, Xing-Shun; Yang, Zhi-Ping; Wu, Kai-Chun; Fan, Dai-Ming; Han, Guo-Hong

    2014-01-01

    AIM: To evaluate the clinical effects of transjugular intrahepatic portosystemic shunt (TIPS) vs endoscopic variceal sclerotherapy (EVS) in the management of gastric variceal (GV) bleeding in terms of variceal rebleeding, hepatic encephalopathy (HE), and survival by meta-analysis. METHODS: Medline, Embase, and CNKI were searched. Studies compared TIPS with EVS in treating GV bleeding were identified and included according to our predefined inclusion criteria. Data were extracted independently by two of our authors. Studies with prospective randomized design were considered to be of high quality. Hazard ratios (HRs) or odd ratios (ORs) were calculated using a fixed-effects model when there was no inter-trial heterogeneity. Oppositely, a random-effects model was employed. RESULTS: Three studies with 220 patients who had at least one episode of GV bleeding were included in the present meta-analysis. The proportions of patients with viral cirrhosis and alcoholic cirrhosis were 39% (range 0%-78%) and 36% (range 12% to 41%), respectively. The pooled incidence of variceal rebleeding in the TIPS group was significantly lower than that in the EVS group (HR = 0.3, 0.35, 95%CI: 0.17-0.71, P = 0.004). However, the risk of the development of any degree of HE was significantly increased in the TIPS group (OR = 15.97, 95%CI: 3.61-70.68). The pooled HR of survival was 1.26 (95%CI: 0.76-2.09, P = 0.36). No inter-trial heterogeneity was observed among these analyses. CONCLUSION: The improved effect of TIPS in the prevention of GV rebleeding is associated with an increased risk of HE. There is no survival difference between the TIPS and EVS groups. Further studies are needed to evaluate the survival benefit of TIPS in cirrhotic patients with GV bleeding. PMID:24868490

  1. Picosecond x-ray measurements from 100 eV to 30 keV

    SciTech Connect

    Attwood, D.T.; Kauffman, R.L.; Stradling, G.L.

    1980-10-15

    Picosecond x-ray measurements relevant to the Livermore Laser Fusion Program are reviewed. Resolved to 15 picoseconds, streak camera detection capabilities extend from 100 eV to higher than 30 keV, with synchronous capabilities in the visible, near infrared, and ultraviolet. Capabilities include automated data retrieval using charge coupled devices (CCD's), absolute x-ray intensity levels, novel cathodes, x-ray mirror/reflector combinations, and a variety of x-ray imaging devices.

  2. Electron-impact excitation of the 31. 4-eV band in N sub 2

    SciTech Connect

    de Souza, G.G.B.; Bielschowsky, C.E.; Lucas, C.A.; Souza, A.C.A. )

    1990-08-01

    Generalized oscillator strengths (GOS) for the dipole-forbidden 31.4-eV band in N{sub 2} have been determined both experimentally and theoretically. The experimental values for the GOS were obtained using a crossed-beam electron spectrometer at 1-keV impact energy. The theoretical results were determined using the first Born approximation with {ital ab} {ital initio} configuration-interaction target wave functions.

  3. Ammonium Sulfate Improves Detection of Hydrophilic Quaternary Ammonium Compounds through Decreased Ion Suppression in Matrix-Assisted Laser Desorption/Ionization Imaging Mass Spectrometry.

    PubMed

    Sugiyama, Eiji; Masaki, Noritaka; Matsushita, Shoko; Setou, Mitsutoshi

    2015-11-17

    Hydrophilic quaternary ammonium compounds (QACs) include derivatives of carnitine (Car) or choline, which are known to have essential bioactivities. Here we developed a technique for improving the detection of hydrophilic QACs using ammonium sulfate (AS) in matrix-assisted laser desorption/ionization-imaging mass spectrometry (MALDI-IMS). In MALDI mass spectrometry for brain homogenates, the addition of AS greatly increased the signal intensities of Car, acetylcarnitine (AcCar), and glycerophosphocholine (GPC) by approximately 300-, 700-, and 2500-fold. The marked improvement required a higher AS concentration than that needed for suppressing the potassium adduction on phosphatidylcholine and 2,5-dihydroxybenzoic acid. Adding AS also increased the signal intensities of Car, AcCar, and GPC by approximately 10-, 20-, and 40-fold in MALDI-IMS. Consequently, the distributions of five hydrophilic QACs (Car, AcCar, GPC, choline, and phosphocholine) were simultaneously visualized by this technique. The distinct mechanism from other techniques such as improved matrix application, derivatization, or postionization suggests the great potential of AS addition to achieve higher sensitivity of MALDI-IMS for various analytes. PMID:26492538

  4. Identification of ion series using ion mobility mass spectrometry: the example of alkyl-benzothiophene and alkyl-dibenzothiophene ions in diesel fuels.

    PubMed

    Maire, Florian; Neeson, Kieran; Denny, Richard; McCullagh, Michael; Lange, Catherine; Afonso, Carlos; Giusti, Pierre

    2013-06-01

    Ion mobility-mass spectrometry (IMMS) has been presented as a promising method for analysis of highly complex mixtures. This coupling adds an additional postionization separation dimension to MS. The IM separation of ions is obtained in the millisecond time scale and can be particularly helpful when chromatographic separation is not possible. For obtaining relevant information about the samples, data processing is usually the bottleneck because of the high amount of data generated with IMMS. In the current work, we present a new workflow using specific comparison software dedicated to IMMS data, which allows one to compare m/z-drift time plots to highlight differences between samples. Two diesel fuels have been compared, i.e., the feed and the product of hydrodesulfurization (HDS) process, and this approach allowed us to clearly highlight the variation of intensity of several ions distributed along the plots of both samples. Accurate mass measurements and post IM collision induced dissociation experiments allowed us to identify two series of polycyclic aromatic sulfur-containing heterocycle (PASH) compounds among the matrix ions. PMID:23638962

  5. Study of the Integrated Immune Response Induced by an Inactivated EV71 Vaccine

    PubMed Central

    Wang, Jingjing; Zhao, Hongling; Jiang, Li; Che, Yanchun; Shi, Haijin; Li, Rongcheng; Mo, Zhaojun; Huang, Teng; Liang, Zhenglun; Mao, Qunying; Wang, Lichun; Dong, Chenghong; Liao, Yun; Guo, Lei; Yang, Erxia; Pu, Jing; Yue, Lei; Zhou, Zhenxin; Li, Qihan

    2013-01-01

    Enterovirus 71 (EV71), a major causative agent of hand-foot-and-mouth disease (HFMD), causes outbreaks among children in the Asia-Pacific region. A vaccine is urgently needed. Based on successful pre-clinical work, phase I and II clinical trials of an inactivated EV71 vaccine, which included the participants of 288 and 660 respectively, have been conducted. In the present study, the immune response and the correlated modulation of gene expression in the peripheral blood mononuclear cells (PBMCs) of 30 infants (6 to 11 months) immunized with this vaccine or placebo and consented to join this study in the phase II clinical trial were analyzed. The results showed significantly greater neutralizing antibody and specific T cell responses in vaccine group after two inoculations on days 0 and 28. Additionally, more than 600 functional genes that were up- or down-regulated in PBMCs were identified by the microarray assay, and these genes included 68 genes associated with the immune response in vaccine group. These results emphasize the gene expression profile of the immune system in response to an inactivated EV71 vaccine in humans and confirmed that such an immune response was generated as the result of the positive mobilization of the immune system. Furthermore, the immune response was not accompanied by the development of a remarkable inflammatory response. Clinical Trial Registration: NCT01391494 and NCT01512706. PMID:23372725

  6. PHEV/EV Li-Ion Battery Second-Use Project (Presentation)

    SciTech Connect

    Neubauer, J.; Pesaran, A.

    2010-04-01

    Accelerated development and market penetration of plug-in hybrid electric vehicles (PHEVs) and electric vehicles (Evs) are restricted at present by the high cost of lithium-ion (Li-ion) batteries. One way to address this problem is to recover a fraction of the battery cost via reuse in other applications after the battery is retired from service in the vehicle, if the battery can still meet the performance requirements of other energy storage applications. In several current and emerging applications, the secondary use of PHEV and EV batteries may be beneficial; these applications range from utility peak load reduction to home energy storage appliances. However, neither the full scope of possible opportunities nor the feasibility or profitability of secondary use battery opportunities have been quantified. Therefore, with support from the Energy Storage activity of the U.S. Department of Energy's Vehicle Technologies Program, the National Renewable Energy Laboratory (NREL) is addressing this issue. NREL will bring to bear its expertise and capabilities in energy storage for transportation and in distributed grids, advanced vehicles, utilities, solar energy, wind energy, and grid interfaces as well as its understanding of stakeholder dynamics. This presentation introduces NREL's PHEV/EV Li-ion Battery Secondary-Use project.

  7. Examining the effect of EVS spending on HCAHPS scores: a value optimization matrix for expense management.

    PubMed

    McCaughey, Deirdre; Stalley, Samantha; Williams, Eric

    2013-01-01

    Using the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey the Centers for Medicare & Medicaid Services' Value-Based Purchasing program has now linked patient care experience rating to hospital revenue reimbursement, thereby establishing a key relationship between revenue cycle management and the patient experience. However, little data exist on the effect of hospital resource spending on patient HCAHPS ratings. This article examines environmental services (EVS) expenses and HCAHPS ratings on hospital cleanliness and overall patient experience ratings to determine how these variables are related. No linear relationship between EVS expense spending and HCAHPS ratings was found, but post hoc analysis identified a matrix that differentiated on hospital cleanliness ratings and overall EVS spending. A value score was calculated for each quadrant of the matrix, and it was determined that organizational value derives from management of expense spending rather than pursuit of high HCAHPS scores. A value optimization matrix is introduced, and its four quadrants are described. With increased emphasis on subjective patient experience measures attached to financial consequences, leaders in the healthcare industry must understand the link between expense management and HCAHPS performance. This study has shown that effective operations are derived from the efficient use of resources and are supported by strong leadership, strategic management, and a culture of patient-centered achievement. The capacity of healthcare organizations to identify their unique costs-to-outcomes balance through the value optimization matrix will help provide them with a means to ensure that optimal value is extracted from all expense spending. PMID:24195341

  8. Countermeasure for Surplus Electricity of PV using Replacement Battery of EVs

    NASA Astrophysics Data System (ADS)

    Takagi, Masaaki; Iwafune, Yumiko; Yamamoto, Hiromi; Yamaji, Kenji; Okano, Kunihiko; Hiwatari, Ryouji; Ikeya, Tomohiko

    In the power sector, the national government has set the goal that the introduction of PV reaches 53 million kW by 2030. However, large-scale introduction of PV will cause several problems in power systems such as surplus electricity. We need large capacity of pumped storages or batteries for the surplus electricity, but the construction costs of these plants are very high. On the other hand, in the transport sector, Electric Vehicle (EV) is being developed as an environmentally friendly vehicle. To promote the diffusion of EV, it is necessary to build infrastructures that can charge EV in a short time; a battery switch station is one of the solutions to this problem. At a station, the automated switch platform will replace the depleted battery with a fully-charged battery. The depleted battery is placed in a storage room and recharged to be available to other drivers. In this study, we propose the use of station's battery as a countermeasure for surplus electricity of PV and evaluate the economic value of the proposed system. We assumed that 53 million kW of PV is introduced in the nationwide power system and considered two countermeasures for surplus electricity: (1) Pumped storage; (2) Battery of station. The difference in total annual cost between Pumped case and Battery case results in 792.6 billion yen. Hence, if a utility leases the batteries from stations fewer than 792.6 billion yen, the utility will have the cost advantage in Battery case.

  9. Observation of vibrationally resolved charge transfer in H + +H2 at ECM=20 eV

    NASA Astrophysics Data System (ADS)

    Niedner, G.; Noll, M.; Toennies, J. P.; Schlier, Ch.

    1987-09-01

    The doubly differential cross sections for both the scattered protons and H atoms have been measured at ELAB=30 eV (ECM=20 eV) from θLAB=0° to 12° (θCM=0° to 18°) for the reactions H++H2(v=0)→H++H2(vf) and →H+H+2(vf) . The energy resolution is sufficient to resolve final vibrational states in both channels. The comparison of both the angular and energy loss distributions for the two product channels provides the first clear experimental evidence of a two-step charge transfer mechanism: Vibrational excitation on the lower H++H2 surface is followed by charge transfer in the outgoing collision for only those H2 molecules which are excited vibrationally high enough (vf≥4) to overcome the endoergic barrier (ΔE=1.83 eV). The final vibrational distributions of H+2 appear to be very similar to those of H2 for vf≥4 indicating that for the angular range observed the charge transfer probability is the same for all vibrational states with vf≥4. The comparison with classical trajectory surface hopping (TSH) calculations points to some disagreement which probably can be attributed to the potential surface used.

  10. High efficiency carbon-based multilayers for LAMP at 250 eV

    NASA Astrophysics Data System (ADS)

    Wen, Mingwu; Huang, Qiushi; She, Rui; Jiang, Li; Zhang, Zhong; Wang, Zhanshan; Feng, Hua; Spiga, Daniele; Giglia, Angelo

    2015-09-01

    X-ray reflection near the Brewster's angle by multilayer mirrors can be used to detect the polarization from X-ray sources. The photon emission spectra from some isolated neutron stars and AGN/blazars etc. show that their emission is peaked at low energies near 250eV, which is just below carbon K-absorption edge. The Lightweight Asymmetry and Magnetism Probe (LAMP) is proposed as a micro-satellite mission dedicated for astronomical X-ray polarimetry working at 250 eV and is currently under early phase study. Co/C multilayers are selected and designed at the energy near 250eV with a grazing incident angle of 45°. The carbon layer thickness ratio is optimized to get the highest integral reflectivity which means larger effective signals in the astrophysics observation. The multilayer coatings were manufactured by direct current magnetron sputtering on D263 glasses and electroformed nickels and characterized using Grazing incidence X-ray reflectometry at 8keV. Reactive sputtering with 4%, 6% and 8% nitrogen were used to improve the Co/C multilayer interfaces respectively. Reflectivity for s-polarization and p-polarization light was measured at BEAR beamline in Elettra synchtron facility. Co/C multilayer deposited with 6% nitrogen exhibits the best performance comparing to other multilayers with different nitrogen content.

  11. Mass loss

    NASA Technical Reports Server (NTRS)

    Goldberg, Leo

    1987-01-01

    Observational evidence for mass loss from cool stars is reviewed. Spectra line profiles are used for the derivation of mass-loss rates with the aid of the equation of continuity. This equation implies steady mass loss with spherical symmetry. Data from binary stars, Mira variables, and red giants in globular clusters are examined. Silicate emission is discussed as a useful indicator of mass loss in the middle infrared spectra. The use of thermal millimeter-wave radiation, Very Large Array (VLA) measurement of radio emission, and OH/IR masers are discussed as a tool for mass loss measurement. Evidence for nonsteady mass loss is also reviewed.

  12. Immunogenicity and protective efficacy of an EV71 virus-like particle vaccine against lethal challenge in newborn mice.

    PubMed

    Sun, Shiyang; Gao, Fan; Mao, Qunying; Shao, Jie; Jiang, Liping; Liu, Dawei; Wang, Yiping; Yao, Xin; Wu, Xing; Sun, Bo; Zhao, Dandan; Ma, Youlei; Lu, Jingcai; Kong, Wei; Jiang, Chunlai; Liang, Zhenglun

    2015-01-01

    Enterovirus 71(EV71) has caused severe epidemics of hand, foot and mouth disease (HFMD) in the Asia Pacific in recent years, particularly in infants and pre-school children. It has become a serious public health threat, as currently there are no approved vaccines or antiviral drugs for EV71 infection. Many EV71 vaccines have been under development worldwide, however the main focus is inactivated EV71 vaccines. For example, the inactivated EV71 vaccine has recently finished phase III clinical trial in Mainland China. There have been very few studies on EV71 virus like particles (VLPs). In this study, the immunogenicity and protective potency of the EV71 VLPs produced in insect cells were evaluated in mice with different dosages. Our results showed that EV71 VLPs could elicit high titers of neutralizing antibodies (NTAbs) in a dose-dependent manner and NTAbs were sustained after the second injection with an average GMT (geometric mean titer) level from 19 to 2960 in immunized mice. Survival rates were 100%, 100%, 85%, and 40% after challenge with 15 LD50 (median lethal dose) of EV71 in these newborn mice, respectively. ED50 (50% effective dose) of VLPs was 0.20 μg/dose in newborn mice, while NTAb titer under this dosage was about 50. Passive protection was determined with 2 methods and demonstrated that the survival rates were positively correlated with NTAb titers, which at 24 and 54 induced 50% survival rates in experimental animals. The ED50 of VLP vaccines and the passive NTAb titers were also analyzed. The maternal NTAb titer was similar as the passive NTAb titer in the mouse model challenged with our lethal mouse EV71 strain. Hence, our work has provided preliminary data on the protection potency of VLPs as a vaccine candidate and would facilitate future VLP vaccine development. PMID:26036916

  13. Immunogenicity and protective efficacy of an EV71 virus-like particle vaccine against lethal challenge in newborn mice

    PubMed Central

    Sun, Shiyang; Gao, Fan; Mao, Qunying; Shao, Jie; Jiang, Liping; Liu, Dawei; Wang, Yiping; Yao, Xin; Wu, Xing; Sun, Bo; Zhao, Dandan; Ma, Youlei; Lu, Jingcai; Kong, Wei; Jiang, Chunlai; Liang, Zhenglun

    2015-01-01

    Enterovirus 71(EV71) has caused severe epidemics of hand, foot and mouth disease (HFMD) in the Asia Pacific in recent years, particularly in infants and pre-school children. It has become a serious public health threat, as currently there are no approved vaccines or antiviral drugs for EV71 infection. Many EV71 vaccines have been under development worldwide, however the main focus is inactivated EV71 vaccines. For example, the inactivated EV71 vaccine has recently finished phase III clinical trial in Mainland China. There have been very few studies on EV71 virus like particles (VLPs). In this study, the immunogenicity and protective potency of the EV71 VLPs produced in insect cells were evaluated in mice with different dosages. Our results showed that EV71 VLPs could elicit high titers of neutralizing antibodies (NTAbs) in a dose-dependent manner and NTAbs were sustained after the second injection with an average GMT (geometric mean titer) level from 19 to 2960 in immunized mice. Survival rates were 100%, 100%, 85%, and 40% after challenge with 15 LD50 (median lethal dose) of EV71 in these newborn mice, respectively. ED50 (50% effective dose) of VLPs was 0.20 μg/dose in newborn mice, while NTAb titer under this dosage was about 50. Passive protection was determined with 2 methods and demonstrated that the survival rates were positively correlated with NTAb titers, which at 24 and 54 induced 50% survival rates in experimental animals. The ED50 of VLP vaccines and the passive NTAb titers were also analyzed. The maternal NTAb titer was similar as the passive NTAb titer in the mouse model challenged with our lethal mouse EV71 strain. Hence, our work has provided preliminary data on the protection potency of VLPs as a vaccine candidate and would facilitate future VLP vaccine development. PMID:26036916

  14. Measuring neutrino masses with weak lensing

    SciTech Connect

    Wong, Yvonne Y. Y.

    2006-11-17

    Weak gravitational lensing of distant galaxies by large scale structure (LSS) provides an unbiased way to map the matter distribution in the low redshift universe. This technique, based on the measurement of small distortions in the images of the source galaxies induced by the intervening LSS, is expected to become a key cosmological probe in the future. We discuss how future lensing surveys can probe the sum of the neutrino masses at the 0 05 eV level.

  15. Abdominal mass

    MedlinePlus

    Several conditions can cause an abdominal mass: Abdominal aortic aneurysm can cause a pulsating mass around the navel. ... This could be a sign of a ruptured aortic aneurysm, which is an emergency condition. Contact your health ...

  16. Abdominal mass

    MedlinePlus

    ... Several conditions can cause an abdominal mass: Abdominal aortic aneurysm can cause a pulsating mass around the navel. ... This could be a sign of a ruptured aortic aneurysm, which is an emergency condition. Contact your health ...

  17. Direct Analysis of Single Cells by Mass Spectrometry at Atmospheric Pressure

    PubMed Central

    Shrestha, Bindesh; Vertes, Akos

    2010-01-01

    Analysis of biochemicals in single cells is important for understanding cell metabolism, cell cycle, adaptation, disease states, etc. Even the same cell types exhibit heterogeneous biochemical makeup depending on their physiological conditions and interactions with the environment. Conventional methods of mass spectrometry (MS) used for the analysis of biomolecules in single cells rely on extensive sample preparation. Removing the cells from their natural environment and extensive sample processing could lead to changes in the cellular composition. Ambient ionization methods enable the analysis of samples in their native environment and without extensive sample preparation.1 The techniques based on the mid infrared (mid-IR) laser ablation of biological materials at 2.94 μm wavelength utilize the sudden excitation of water that results in phase explosion.2 Ambient ionization techniques based on mid-IR laser radiation, such as laser ablation electrospray ionization (LAESI) and atmospheric pressure infrared matrix-assisted laser desorption ionization (AP IR-MALDI), have successfully demonstrated the ability to directly analyze water-rich tissues and biofluids at atmospheric pressure.3-11 In LAESI the mid-IR laser ablation plume that mostly consists of neutral particulate matter from the sample coalesces with highly charged electrospray droplets to produce ions. Recently, mid-IR ablation of single cells was performed by delivering the mid-IR radiation through an etched fiber. The plume generated from this ablation was postionized by an electrospray enabling the analysis of diverse metabolites in single cells by LAESI-MS.12 This article describes the detailed protocol for single cell analysis using LAESI-MS. The presented video demonstrates the analysis of a single epidermal cell from the skin of an Allium cepa bulb. The schematic of the system is shown in Figure 1. A representative example of single cell ablation and a LAESI mass spectrum from the cell are provided in

  18. Structural mass spectrometry of tissue extracts to distinguish cancerous and non-cancerous breast diseases

    PubMed Central

    Hines, K. M.; Ballard, B. R.

    2014-01-01

    Breast cancer is well-known to broadly impact cellular metabolism and aberrant metabolism in breast cancer tumors has been widely studied by both targeted and untargeted analyses to characterize the affected metabolic pathways. In this work, we utilize ultra-performance liquid chromatography (UPLC) in tandem with ion mobility-mass spectrometry (IM-MS), which provides chromatographic, structural, and mass information, to characterize the aberrant metabolism associated with breast diseases such as cancer. In a double-blind analysis of matched control (n=3) and disease tissues (n=3), tissues were homogenized, polar metabolites were extracted, and the extracts were characterized by UPLC-IM-MS/MS. Principle component analysis revealed a strong separation between disease tissues, with one diseased tissue clustering with the control tissues along PC1 and two others separated along PC2. Using postion mobility MS/MS spectra acquired by data-independent acquisition, the features giving rise to the observed grouping were determined to be biomolecules associated with aggressive breast cancer tumors, including glutathione, oxidized glutathione, thymosins β4 and β10, and choline-containing species. Pathology reports revealed the outlier of the disease tissues to be a benign fibroadenoma, whereas the other disease tissues represented highly metabolic benign and aggressive tumors. This IM-MS-based workflow bridges the transition from untargeted metabolomic profiling to tentative identifications of key descriptive molecular features using data acquired in one analysis, with additional experiments performed only for validation. The ability to resolve cancerous and non-cancerous tissues at the biomolecular level demonstrates UPLC-IM-MS/MS as a robust and sensitive platform for metabolomic profiling of tissues. PMID:25212505

  19. Design and performance of an instrument for electron impact tandem mass spectrometry and action spectroscopy of mass/charge selected macromolecular ions stored in RF ion trap*

    NASA Astrophysics Data System (ADS)

    Ranković, Milos Lj.; Giuliani, Alexandre; Milosavljević, Aleksandar R.

    2016-05-01

    A new apparatus was designed, coupling an electron gun with a linear quadrupole ion trap mass spectrometer, to perform m/z (mass over charge) selected ion activation by electron impact for tandem mass spectrometry and action spectroscopy. We present in detail electron tracing simulations of a 300 eV electron beam inside the ion trap, design of the mechanical parts, electron optics and electronic circuits used in the experiment. We also report examples of electron impact activation tandem mass spectra for Ubiquitin protein, Substance P and Melittin peptides, at incident electron energies in the range from 280 eV to 300 eV. Contribution to the Topical Issue "Advances in Positron and Electron Scattering", edited by Paulo Limao-Vieira, Gustavo Garcia, E. Krishnakumar, James Sullivan, Hajime Tanuma and Zoran Petrovic.

  20. InterEvDock: a docking server to predict the structure of protein-protein interactions using evolutionary information.

    PubMed

    Yu, Jinchao; Vavrusa, Marek; Andreani, Jessica; Rey, Julien; Tufféry, Pierre; Guerois, Raphaël

    2016-07-01

    The structural modeling of protein-protein interactions is key in understanding how cell machineries cross-talk with each other. Molecular docking simulations provide efficient means to explore how two unbound protein structures interact. InterEvDock is a server for protein docking based on a free rigid-body docking strategy. A systematic rigid-body docking search is performed using the FRODOCK program and the resulting models are re-scored with InterEvScore and SOAP-PP statistical potentials. The InterEvScore potential was specifically designed to integrate co-evolutionary information in the docking process. InterEvDock server is thus particularly well suited in case homologous sequences are available for both binding partners. The server returns 10 structures of the most likely consensus models together with 10 predicted residues most likely involved in the interface. In 91% of all complexes tested in the benchmark, at least one residue out of the 10 predicted is involved in the interface, providing useful guidelines for mutagenesis. InterEvDock is able to identify a correct model among the top10 models for 49% of the rigid-body cases with evolutionary information, making it a unique and efficient tool to explore structural interactomes under an evolutionary perspective. The InterEvDock web interface is available at http://bioserv.rpbs.univ-paris-diderot.fr/services/InterEvDock/. PMID:27131368

  1. Resolution of time-of-flight mass spectrometers evaluated for secondary neutral mass spectrometry

    NASA Astrophysics Data System (ADS)

    Kato, Makoto; Mogami, Akinori; Naito, Motohiro; Ichimura, Shingo; Shimizu, Hazime

    1988-09-01

    Mass resolution of a time-of-flight mass spectrometer with a two-stage electrostatic reflector is calculated for secondary neutral mass spectrometry. The instrument parameters are optimized for energy and space focusing: correcting the flight time difference due to the energy width ΔE of sputtered particles and the spatial width Δs of an ionizing laser beam. The effect of Δs can be compensated by applying an acceleration field to the ionizing region, and the maximum resolution becomes about 1000 for ΔE=10 eV and Δs=1.0 mm.

  2. The atomic branching ratios in the photodissociation N2, CO, and CO2 in the deep VUV from 11.50-15.15 eV is used to discuss the chemistry in comets, planetary atmospheres, protoplanetary disk, and dense molecular clouds.

    NASA Astrophysics Data System (ADS)

    Jackson, William M.; Song, Yu; Lu, Zhou; Gao, Hong; Chang, Yih C.; Zhou, Jingang; Shi, Xiayou; Pan, Yang; Yang, Lei; Yin, Qing Z.; Ng, Cheuk Y.

    2014-11-01

    The only pulsed molecular beam apparatus in the world with two tunable VUV lasers coupled to a time of flight mass spectrometer and a time-slice velocity imaging detector is used to determine the state of atomic products produced in the photodissociation of N2, CO, and CO2. This information is extremely important in modeling the chemistry in comets, planetary atmospheres, protoplanetary disk, and dense molecular clouds. For N2 reactions 2-4 are directly observed.N2 + hν → N(4S) + N(4S) hν ≥ 9.76 eV (1)→ N(4S) + N(2D) hν ≥ 12.14 eV (2)→ N(4S) + N(2P) hν ≥ 13.34 eV (3)→ N(2D) + N(2D) hν ≥ 14.53 eV (4)No evidence is found for the lowest energy channel that produces two N(4S) anywhere in this wavelength range.The products from the photodissociation of CO between 12.361-13.180 eV are determined and discussed.CO + hν → C(3PJ) + O(3PJ) hν ≥ 11.09 eV (5)→ C(1D) + O(3PJ) hν ≥ 12.35 eV (6)→ C(3PJ) + O(1D) hν ≥ 13.06 eV (7) In the photodissociation of CO2 over the wavelength range from 94,000- 98,496 cm-1 (11.655-12.212eV) and (13.540-13.678 eV) CO2 reactions 8-15 occur.CO2 + hν → (O3PJ) + CO(X1Σ +) hν ≥ 5.45 eV (8)→ O(1D) + CO(X1Σ+) hν ≥ 7.42 eV (9)→ O(1S) + CO(X1Σ+) hν ≥ 9.64 eV (10)→ O(3PJ) + CO(a3Π) hν ≥ 11.46 eV (11)→ O(1D) + CO(a3Π) hν ≥ 13.43 eV (12)→ O(3PJ) + CO(a'3Σ+) hν ≥ 12.31 eV (13)→ O(3PJ) + CO(d 3Δ) hν ≥ 12.97 eV (14)→ O(3PJ) + CO(e 3Σ-) hν ≥ 13.35 eV (15)The implications of these results to planetary science in terms of the chemical reactions of the long lived metastable N(2D), N(2P), O(1D), O(1S), and C(1D) will be discussed. Acknowledgements:William M. Jackson, Yu Song, Hong Gao, Xiayou Shi and Zhou Lu were supported NSF under Grants No. CHE-1301501 and CHE-957872. Cheuk Y. Ng was supported by US-DOE under Contract No. DE-FG02-02ER15306.

  3. Mass spectrometry.

    NASA Technical Reports Server (NTRS)

    Burlingame, A. L.; Johanson, G. A.

    1972-01-01

    Review of the current state of mass spectrometry, indicating its unique importance for advanced scientific research. Mass spectrometry applications in computer techniques, gas chromatography, ion cyclotron resonance, molecular fragmentation and ionization, and isotope labeling are covered. Details are given on mass spectrometry applications in bio-organic chemistry and biomedical research. As the subjects of these applications are indicated alkaloids, carbohydrates, lipids, terpenes, quinones, nucleic acid components, peptides, antibiotics, and human and animal metabolisms. Particular attention is given to the mass spectra of organo-inorganic compounds, inorganic mass spectrometry, surface phenomena such as secondary ion and electron emission, and elemental and isotope analysis. Further topics include mass spectrometry in organic geochemistry, applications in geochronology and cosmochemistry, and organic mass spectrometry.

  4. KATRIN: Measuring the Mass Scale of Neutrinos

    NASA Astrophysics Data System (ADS)

    Oblath, Noah; Katrin Collaboration

    2011-10-01

    Over the past decade, experiments studying neutrinos from atmospheric, solar, and reactor sources have shown conclusively that neutrinos change flavor and, as a consequence, have a small but finite mass. However, the scale of neutrino masses remains an open question that is of great importance for many areas of physics. The most direct method to measure the neutrino mass scale is still via beta decay. The talk will focus primarily on the status of the KArlsruhe TRItium Neutrino experiment (KATRIN), currently under construction. KATRIN combines an ultra-luminous molecular windowless gaseous tritium source with a high-resolution integrating spectrometer to gain sensitivity to the absolute mass scale of neutrinos. The projected sensitivity of the experiment on the neutrino mass is 0.2 eV at 90% C.L. In this talk I will discuss the status of the KATRIN experiment.

  5. Vibrational excitation in CO by electron impact in the energy range 10-90 eV.

    NASA Technical Reports Server (NTRS)

    Chutjian, A.; Truhlar, D. G.; Williams, W.; Trajmar, S.

    1972-01-01

    The ratio of the scattering intensity for the v double prime = 1 excitation to the elastic scattering intensity at 40- and 80-deg scattering angles has been determined for 10- to 90-eV impact energies for electron scattering by CO. These ratio curves exhibit broad peaks near 20-eV impact energy which cannot be accounted for by plane-wave calculations based on potential scattering models. The peaks are indicative of a resonant excitation process (or processes) in the v double prime = 1 channel in the range from 15 to 25 eV.

  6. Broadband extreme ultraviolet multilayer mirror for supercontinuum light at a photon energy of 35-65 eV

    SciTech Connect

    Hatayama, Masatoshi; Takenaka, Hisataka; Gullikson, Eric M.; Suda, Akira; Midorikawa, Katsumi

    2009-10-10

    We have developed a broadband multilayer mirror for photon energies between 35 and 65 eV. This extreme ultraviolet (EUV) mirror has an almost flat reflectivity profile at normal incidence, and the average reflectivity is 8%. The bandwidth of this mirror is 30 eV centered around 50 eV, 1.5 times broader than conventional multilayer mirrors in this energy region. This new mirror can be used in a variety of applications using supercontinuum EUV light sources including attosecond metrology.

  7. Optical constants and related electronic energy bands of lithium triborate crystal in the 6{endash}12-eV region

    SciTech Connect

    Chen, T.; Tao, R.; Rife, J.C.; Hunter, W.R.

    1998-01-01

    Reflectance of lithium triborate crystal in the 6{endash}12-eV region is measured with synchrotron radiation, and the principal values of optical constants are derived. Six absorption peaks are found in both X- and Y-polarized spectra. Among them the five transitions of the Y-polarized peaks and three of the X-polarized peaks are identified. The measurement suggests that the energy of the lowest conducting band 4A{sub 2} is 7.3 eV rather than 7.57 eV, as previously reported. {copyright} 1998 Optical Society of America

  8. Constraining light gravitino mass from cosmic microwave background

    SciTech Connect

    Ichikawa, Kazuhide; Kawasaki, Masahiro; Nakayama, Kazunori; Sekiguchi, Toyokazu; Takahashi, Tomo E-mail: kawasaki@icrr.u-tokyo.ac.jp E-mail: sekiguti@icrr.u-tokyo.ac.jp

    2009-08-01

    We investigate the possibilities of constraining the light gravitino mass m{sub 3/2} from future cosmic microwave background (CMB) surveys. A model with light gravitino with the mass m{sub 3/2} < O(10) eV is of great interest since it is free from the cosmological gravitino problem and, in addition, can be compatible with many baryogenesis/leptogenesis scenarios such as the thermal leptogenesis. We show that the lensing of CMB anisotropies can be a good probe for m{sub 3/2} and obtain an expected constraint on m{sub 3/2} from precise measurements of lensing potential in the future CMB surveys, such as the PolarBeaR and CMBpol experiments. If the gravitino mass is m{sub 3/2} = 1 eV, we will obtain the constraint for the gravitino mass as m{sub 3/2} ≤ 3.2 eV (95%C.L.) for the case with Planck+PolarBeaR combined and m{sub 3/2} = 1.04{sup +0.22}{sub −0.26} eV (68%C.L.) for CMBpol. The issue of Bayesian model selection is also discussed.

  9. Electron-impact excitation of UF6 at an electron energy of 20 eV in the energy-loss range of 0-10 eV

    NASA Technical Reports Server (NTRS)

    Chutjian, A.; Srivastava, S. K.; Trajmar, S.; Williams, W.; Cartwright, D. C.

    1976-01-01

    A technique combining electron impact excitation and optical absorption spectroscopy was applied to UF6. The crucial features of the experiment were that: (1) the electron optics was differentially pumped relative to the scattering chamber and (2) the target UF6 beam was condensed on a liquid nitrogen cold trap placed immediately above the scattering center. Energy loss spectra are presented at an incident electron energy of 20 eV and at scattering angles between 20 and 135 degrees. It is shown that no transitions are found below the first-detected feature at 3.0 eV and an optically forbidden excitation is found at 4.2 eV. A fairly strong optical absorption at 4.8 eV is observed to 'fill-in' at a scattering angle of 20 degrees but is practically absent at higher angles.

  10. Polarization and absorption effects in electron-helium scattering at 30--400 eV

    SciTech Connect

    Thirumalai, D.; Truhlar, D.G.; Brandt, M.A.; Eades, R.A.; Dixon, D.A.

    1982-06-01

    We report several calculations of the differential, integral, and momentum-transfer cross sections for elastic scattering, and of the absorption cross sections (for the sum of all electronically inelastic and ionization processes) for electron-He collisions at 30--400 eV. We consider two basically different approaches to include the effect of absorption, i.e., loss of flux from the initial channel. The first is the matrix effective potential (MEP) based on a variational calculation of the polarization potential; this models absorption by including a pseudochannel whose properties are based on a variational adiabatic polarization potential. This method predicts both the absorption and elastic cross sections. The second method involves phenomenological absorption (A) potentials, calibrated against experimental absorption cross sections. These potentials, when combined with static (S), exchange (E), and real polarization (P) potentials form an SEPA optical model potential that is used to predict the elastic cross sections. The MEP model based on the variational polarization potential predicts the absorption cross sections with an average absolute error of 28% at 30 and 50 eV and 5% at 100--400 eV. It predicts the elastic integral cross sections with an average absolute error of 8% over the whole energy range. The SEPA models, including a nonadiabatic polarization potential, predict the elastic integral cross sections with average absolute errors of 12 or 6%, depending on the shape function (i.e., r dependence) of the absorption potential. The adiabatic approximation for polarization is less accurate than the nonadiabatic one, even when absorption effects are included. Five new calculations of the differential cross sections at each of five impact energies are compared to experimental results in detail.

  11. Polarization and absorption effects in electron-helium scattering at 30-400 eV

    NASA Astrophysics Data System (ADS)

    Thirumalai, Devarajan; Truhlar, Donald G.; Brandt, Maynard A.; Eades, Robert A.; Dixon, David A.

    1982-06-01

    We report several calculations of the differential, integral, and momentum-transfer cross sections for elastic scattering, and of the absorption cross sections (for the sum of all electronically inelastic and ionization processes) for electron-He collisions at 30-400 eV. We consider two basically different approaches to include the effect of absorption, i.e., loss of flux from the initial channel. The first is the matrix effective potential (MEP) based on a variational calculation of the polarization potential; this models absorption by including a pseudochannel whose properties are based on a variational adiabatic polarization potential. This method predicts both the absorption and elastic cross sections. The second method involves phenomenological absorption (A) potentials, calibrated against experimental absorption cross sections. These potentials, when combined with static (S), exchange (E), and real polarization (P) potentials form an SEPA optical model potential that is used to predict the elastic cross sections. The MEP model based on the variational polarization potential predicts the absorption cross sections with an average absolute error of 28% at 30 and 50 eV, and 5% at 100-400 eV. It predicts the elastic integral cross sections with an average absolute error of 8% over the whole energy range. The SEPA models, including a nonadiabatic polarization potential, predict the elastic integral cross sections with average absolute errors of 12 or 6%, depending on the shape function (i.e., r dependence) of the absorption potential. The adiabatic approximation for polarization is less accurate than the nonadiabatic one, even when absorption effects are included. Five new calculations of the differential cross sections at each of five impact energies are compared to experimental results in detail.

  12. Impact of Fast Charging on Life of EV Batteries; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    Neubauer, Jeremy; Wood, Eric; Burton, Evan; Smith, Kandler; Pesaran, Ahmad

    2015-05-03

    Installation of fast charging infrastructure is considered by many as one of potential solutions to increase the utility and range of electric vehicles (EVs). This is expected to reduce the range anxiety of drivers of EVs and thus increase their market penetration. Level 1 and 2 charging in homes and workplaces is expected to contribute to the majority of miles driven by EVs. However, a small percentage of urban driving and most of inter-city driving could be only achieved by a fast-charging network. DC fast charging at 50 kW, 100 kW, 120 kW compared to level 1 (3.3 kW) and level 2 (6.6 kW) results in high-current charging that can adversely impact the life of the battery. In the last couple of years, we have investigated the impact of higher current rates in batteries and potential of higher temperatures and thus lower service life. Using mathematical models, we investigated the temperature increase of batteries due to higher heat generation during fast charge and have found that this could lead to higher temperatures. We compared our models with data from other national laboratories both for fine-tuning and calibration. We found that the incremental temperature rise of batteries during 1C to 3C fast charging may reduce the practical life of the batteries by less than 10% over 10 to 15 years of vehicle ownership. We also found that thermal management of batteries is needed for fast charging to prevent high temperature excursions leading to unsafe conditions.

  13. Femtosecond two-photon ionization of fluid NH3 at 9.3 eV

    NASA Astrophysics Data System (ADS)

    Urbanek, Janus; Dahmen, Annika; Torres-Alacan, Joel; Vöhringer, Peter

    2013-03-01

    Liquid and supercritical ammonia (NH3) is photo-ionized at an energy of 9.3 eV with 100-fs duration pulses at a wavelength of 266 nm. The ionization involves two photons and generates fully solvated electrons via the conduction band of the solvent within the time resolution of the experiment. The dynamics of their ensuing geminate recombination is followed in real time with femtosecond near-infrared (IR) probe pulses. The recombination mechanism can be understood as an ion-pair mediated reaction. The electron survival probability is found to be in quantitative agreement with the classical Onsager theory for the initial recombination of ions.

  14. Multichannel processes of H2O in the 18 eV region

    NASA Technical Reports Server (NTRS)

    Wu, C. Y. Robert; Judge, D. L.

    1988-01-01

    Measurements were made of: (1) the fluorescence cross sections of OH(A 2Sigma+) fragments; (2) the absolute cross sections producing H atoms in the n = 2, 3, and 4 states; (3) the cross section for producing excited O atoms which has an upper limit of 5 x 10 to the -21 sq cm; and (4) the fluorescence cross section for producing H2(a 3Sigma g +) fragments. It is shown that, in the 16-20 eV region, there are excellent correspondences in the peak positions and spacings among the photoabsorption, photoionization spectra, and fluorescence functions of OH(A) and H(n).

  15. Undulator based synchrotron radiation source in the 5-30 eV spectral region

    SciTech Connect

    Zhang, Xiaohao; Murphy, J.B.; Krinsky, S.

    1991-01-01

    There has been recent interest in the utilization of high intensity radiation in the 5-30 eV spectral region. Applications include angle resolved photoemission, photochemistry, and radiation oncology. Here we present the design of a 500 MeV electron storage ring with long insertions for undulators. The ring is designed to provide an emittance of 0.1 mm-mrad, an average current of 1 Amp and an electron beam lifetime of greater than 3 hrs. The undulators operating near K{equals}1, yield 10{sup 15} ph/sec/0.1{percent} bandwidth in the fundamental. 5 refs.

  16. Differential elastic scattering cross sections for 54.9eV positrons incident on helium

    NASA Technical Reports Server (NTRS)

    Chaplin, R. L.; Diana, L. M.; Brooks, D. L.

    1990-01-01

    Absolute differential elastic scattering cross sections measured with the 3-m, high resolution, time-of-flight spectrometer are presented for 54.9eV positrons incident on He. Five point moving average differential cross sections are plotted against average scattering angles which range from 14 to 36 deg. Also the averages of five differential cross sections which have adjacent values of scattering angle are plotted versus the corresponding averages of the scattering angles. The curve fitted to these data is shaped like the theoretical curve but has its minimum and its maximum at scattering angles that are about 4 deg higher and 15 deg lower respectively than predicted by theory.

  17. The cosmic ray spectrum above 10(17) eV

    NASA Technical Reports Server (NTRS)

    Winn, M. M.; Ulrichs, J.; Horton, L.; Mccusker, C. B. A.; Peak, L. S.

    1986-01-01

    The final analysis of the data obtained by the Sydney University Giant Airshower Recorder (SUGAR) is presented. The data has been reanalysed to take into account the effects of afterpulsing in the photomultiplier tubes. Event data was used to produce a spectrum of equivalent vertical muon number and from this a model dependent primary energy spectrum was obtained. These spectra show good evidence for the Ankle: a flattening at 10(19) eV. There is no sign of the cut-off which would be expected from the effects of the universal black body radiation.

  18. Properties of 10 (18)-10 (19)eV EAS at far core distance

    NASA Technical Reports Server (NTRS)

    Hara, T.; Hatano, Y.; Ishikawa, F.; Kamata, K.; Matsubara, Y.; Teshima, M.; Nagano, M.; Hayashida, N.; He, C. X.; Honda, M.

    1985-01-01

    The properties of 10 to the 18th power - 10 to the 19th power eV EAS showers such as the electron lateral distribution, the muon lateral distribution ( 1Gev), the ratio of muon density to a electron density, the shower front structure and the transition effects in scintillator of 5cm thickness are investigated with the Akeno 4 sq km/20sq km array at far core distances between 500m and 3000m. The fluctuation of densities and arrival time increase rapidly at core distances greater than 2km.

  19. Skid Prevention Control for IPMSM Driven EVs Based on Improved Torque Reduction Characteristics

    NASA Astrophysics Data System (ADS)

    Satake, Masamitsu; Kawashima, Kiyotaka; Uchida, Toshiyuki; Hori, Yoichi

    In this paper, skid prevention control based on torque reduction is proposed for EVs driven by an IPMSM. The traction characteristics of the electric vehicle are improved by using a modified current controller to rapidly reduce the torque of the driving motor. In order to compensate for back-EMF, a disturbance observer is introduced. In addition, we propose skid prevention for an IPMSM by torque reduction using both the dq-axes currents. Further, we verify the effect of each control method by conducting experiments in which the electric vehicle is driven on a slippery road.

  20. Electron-impact ionization of molecular hydrogen at 38 eV incident energy

    NASA Astrophysics Data System (ADS)

    Colgan, James; Ren, Xueguang; Dorn, Alexander; Pindzola, M. S.

    2016-05-01

    We report on recent measurements of the triple differential cross sections from electron-impact ionization of molecular hydrogen at an incident energy of 38 eV. Results are reported for various orientations of the target molecule, as well as various scattering angles and energy sharings of the outgoing electrons. The measurements are compared with calculations performed using a time-dependent close-coupling approach. Reasonable agreement is found between theory and measurement. We also compare and contrast our results to those obtained at higher incident electron energies, which were reported recently.

  1. Photoelectron spectrum of Ca between 11 and 28 eV

    SciTech Connect

    Cowan, R.D.; Hansen, J.E.; Smid, H.

    1985-04-01

    We present a calculation of the photon energy dependence of the photoelectron spectrum of Ca from 11 to 28 eV, roughly the region between the 4p threshold and the lowest resonance due to 3p..-->..3d excitations. Because of the occurrence of a ''Cooper minimum'' for 4s..-->..epsilonp excitation close to threshold, which is not reproduced for the satellites, we predict that at low photon energy the 3d and particularly the 4p satellite will be stronger than the main 4s line.

  2. Oxygen vacancy and EC - 1 eV electron trap in ZnO

    NASA Astrophysics Data System (ADS)

    Chicot, Gauthier; Muret, Pierre; Santailler, Jean-Louis; Feuillet, Guy; Pernot, Julien

    2014-11-01

    Fourier transform deep level transient spectroscopy has been performed between 80 and 550 K in five n-type ZnO samples grown by different techniques. The capture cross section and ionization energy of four electron traps have been deduced from Arrhenius diagrams. A trap 1 eV below the conduction band edge is systematically observed in the five samples with a large apparent capture cross section for electrons (1.6 ± 0.4 × 10-13 cm2) indicating a donor character. The assignment of this deep level to the oxygen vacancy is discussed on the basis of available theoretical predictions.

  3. Optical properties of bcc transition metals in the range 0-40eV

    NASA Astrophysics Data System (ADS)

    Romaniello, P.; de Boeij, P. L.; Carbone, F.; van der Marel, D.

    2006-02-01

    We present a systematic analysis of the optical properties of bcc transition metals in the groups VB: V, Nb, and Ta, and VIB: paramagnetic Cr, Mo, and W. For this we use our formulation of time-dependent current-density-functional theory for the linear response of metals. The calculated dielectric and electron energy-loss functions are compared with our ellipsometry measurements and with data reported in literature, showing an overall good agreement. The experimental data of the dielectric functions presented by Nestell and Christy and by Weaver differ mostly in the low-frequency region. However, we found that their reflectivity data are in very good agreement up to about 3eV . We attribute this apparent discrepancy to the Drude-like extrapolation model used by Weaver in the Kramers-Kronig procedure to extract the optical constants from their reflectivity data. Our experiments are in good agreement with Nestell and Christy’s data. The calculated absorption spectra show some deviations from the experiments, in particular in the 3d metals. We assign the spectra in terms of transitions between pairs of bands and we analyze which parts of the Brillouin zone are mainly involved in the absorption. Our results suggest that the blueshift of some spectral features in our calculations can be attributed mainly to the incorrect description of the virtual d bands by the approximations used for the ground state exchange-correlation functional. These virtual bands are too weakly bound by the local density and generalized gradient approximations, in particular in the 3d metals. We calculate separately the inter- and intraband contributions to the absorption and we show using a k•p analysis that, within the scalar-relativistic approximation, interband transitions contribute to the absorption already at frequencies well below 0.5eV . This finding makes questionable the Drude-like behavior normally assumed in the experimental analysis of the linear response. We find that the

  4. MoS2 interactions with 1.5 eV atomic oxygen

    NASA Technical Reports Server (NTRS)

    Martin, J. A.; Cross, J. B.; Pope, L. E.

    1989-01-01

    Exposures of MoS2 to 1.5-eV atomic oxygen in an anhydrous environment reveal that the degree of oxidation is essentially independent of crystallite orientation, and that the surface-adsorbed reaction products are MoO3 and MoO2. A mixture of oxides and sulfide exists over a depth of about 90 A, and this layer has a low diffusion rate for oxygen. It is concluded that a protective oxide layer forms on MoS2 on exposure to the atomic-oxygen-rich environment of LEO.

  5. Optical constants of lithium triborate crystals in the 55--71 eV region

    SciTech Connect

    Chen, T.; Zitter, R.N.; Tao, R.; Hunter, W.R.; Rife, J.C.

    1995-11-15

    The reflectances of lithium triborate (LBO) crystals in the range 55--71 eV have been measured and the principal values of the optical constants are derived. Five transitions in this spectral region are observed and their oscillator strengths and matrix elements {l_angle}{ital x}{r_angle},{l_angle}{ital y}{r_angle},{l_angle}{ital z}{r_angle} are determined. LBO is strongly anisotropic in this region and its energy levels are mainly determined by the Li ion.

  6. Constraints on neutrino masses from future cosmological observations

    SciTech Connect

    Hirano, Koichi

    2014-05-02

    Constraints on neutrino masses are estimated based on future observations of the cosmic microwave background (CMB) including the B-mode polarization produced by CMB lensing using the Planck satellite, and baryon acoustic oscillations distance scale and the galaxy power spectrum from all-sky galaxy redshift survey in the BigBOSS experiment. We estimate the error in the bound on the total neutrino mass to be Δ∑m{sub v} = 0.012 eV with a 68% confidence level. If the fiducial value of the total neutrino mass is ∑m{sub v} = 0.06 eV, this result implies that the neutrino mass hierarchy must be normal.

  7. MASS SPECTROMETER

    DOEpatents

    White, F.A.

    1960-08-23

    A mass spectrometer is designed with a first adjustable magnetic field for resolving an ion beam into beams of selected masses, a second adjustable magnetic field for further resolving the ion beam from the first field into beams of selected masses, a thin foil disposed in the path of the beam between the first and second magnets to dissociate molecular ions incident thereon, an electrostatic field for further resolving the ion beam from the second field into beams of selected masses, and a detector disposed adjacent to the electrostatic field to receive the ion beam.

  8. The origin of 0.78 eV line of the dislocation related luminescence in silicon

    SciTech Connect

    Xiang Luelue; Li Dongsheng; Jin Lu; Yang Deren; Pivac, Branko

    2012-09-15

    In this paper, the 0.78 eV line of the dislocation related luminescence in the electron-irradiated silicon has been investigated. It is found that the 0.78 eV line only exists in float zone silicon samples, and its intensity could be largely enhanced by high temperature and long time annealing while no 0.78 eV line was found in Czochralski silicon. The activation energy of 0.78 eV line in floating-zone silicon is {approx}13 meV, indicating a different nature from that of D1/D2 lines which can be ascribed to specific reconstructed dislocations which could be easily affected by point defects and temperature.

  9. Measurement of the composition and energy spectrum of cosmic rays above 10 sup 15 eV

    SciTech Connect

    Berley, D. ); Ellsworth, R.W. )

    1990-03-20

    The availability of a launch vehicle with the capability of carrying a heavy payload, would make possible several definitive experiments including: (1) the determination of the composition and energy spectrum of cosmic rays up to 10{sup 12} electron volts (eV) (2) the observation of gamma rays from compact sources, up to energies of 10{sup 12} eV. The instrument proposed, weighing about 30 tons, is designed to address these fundamental questions.

  10. Racism, the Left and Twenty-First-Century Socialism: Some Observations on the Gur-Ze'ev/McLaren Interchange

    ERIC Educational Resources Information Center

    Cole, Mike

    2013-01-01

    The Gur-Ze'ev/McLaren interchange covered a wide range of issues that are important for twenty-first century socialists. In this article, the author concentrates on two of them: first, Gur-Ze'ev's charge that critical pedagogy is part of the "new anti-Semitism"; second, his critique of McLaren's support for Hugo Chavez and the Bolivarian model of…

  11. Recombination reactions of 5-eV O(3P) atoms on a MgF2 surface

    NASA Technical Reports Server (NTRS)

    Orient, O. J.; Chutjian, A.; Murad, E.

    1990-01-01

    A source of hyperthermal, ground-state, impurity-free, atomic oxygen of an energy variable in the range 2-100 eV has been developed. Experimental results are presented of emission spectra in the wavelength range 250-850 nm produced by collisions of 5-eV O(3P) atoms with adsorbed NO and CO molecules on a MgF2 surface.

  12. Influence of organic ions on DNA damage induced by 1 eV to 60 keV electrons

    NASA Astrophysics Data System (ADS)

    Zheng, Yi; Sanche, Léon

    2010-10-01

    We report the results of a study on the influence of organic salts on the induction of single strand breaks (SSBs) and double strand breaks (DSBs) in DNA by electrons of 1 eV to 60 keV. Plasmid DNA films are prepared with two different concentrations of organic salts, by varying the amount of the TE buffer (Tris-HCl and EDTA) in the films with ratio of 1:1 and 6:1 Tris ions to DNA nucleotide. The films are bombarded with electrons of 1, 10, 100, and 60 000 eV under vacuum. The damage to the 3197 base-pair plasmid is analyzed ex vacuo by agarose gel electrophoresis. The highest yields are reached at 100 eV and the lowest ones at 60 keV. The ratios of SSB to DSB are surprisingly low at 10 eV (˜4.3) at both salt concentrations, and comparable to the ratios measured with 100 eV electrons. At all characteristic electron energies, the yields of SSB and DSB are found to be higher for the DNA having the lowest salt concentration. However, the organic salts are more efficient at protecting DNA against the damage induced by 1 and 10 eV electrons. DNA damage and protection by organic ions are discussed in terms of mechanisms operative at each electron energy. It is suggested that these ions create additional electric fields within the groove of DNA, which modify the resonance parameter of 1 and 10 eV electrons, namely, by reducing the electron capture cross-section of basic DNA units and the lifetime of corresponding transient anions. An interstrand electron transfer mechanism is proposed to explain the low ratios for the yields of SSB to those of DSB produced by 10 eV electrons.

  13. Influence of organic ions on DNA damage induced by 1 eV to 60 keV electrons

    SciTech Connect

    Zheng Yi; Sanche, Leon

    2010-10-21

    We report the results of a study on the influence of organic salts on the induction of single strand breaks (SSBs) and double strand breaks (DSBs) in DNA by electrons of 1 eV to 60 keV. Plasmid DNA films are prepared with two different concentrations of organic salts, by varying the amount of the TE buffer (Tris-HCl and EDTA) in the films with ratio of 1:1 and 6:1 Tris ions to DNA nucleotide. The films are bombarded with electrons of 1, 10, 100, and 60 000 eV under vacuum. The damage to the 3197 base-pair plasmid is analyzed ex vacuo by agarose gel electrophoresis. The highest yields are reached at 100 eV and the lowest ones at 60 keV. The ratios of SSB to DSB are surprisingly low at 10 eV ({approx}4.3) at both salt concentrations, and comparable to the ratios measured with 100 eV electrons. At all characteristic electron energies, the yields of SSB and DSB are found to be higher for the DNA having the lowest salt concentration. However, the organic salts are more efficient at protecting DNA against the damage induced by 1 and 10 eV electrons. DNA damage and protection by organic ions are discussed in terms of mechanisms operative at each electron energy. It is suggested that these ions create additional electric fields within the groove of DNA, which modify the resonance parameter of 1 and 10 eV electrons, namely, by reducing the electron capture cross-section of basic DNA units and the lifetime of corresponding transient anions. An interstrand electron transfer mechanism is proposed to explain the low ratios for the yields of SSB to those of DSB produced by 10 eV electrons.

  14. Optical Constants of Uranium Nitride in the XUV (80--182 eV)

    NASA Astrophysics Data System (ADS)

    Urry, Marie; Allred, David D.; Adamson, Kristi; Bissell, Luke; Turley, R. Steven

    2003-10-01

    The reported optical constants of uranium differ from those of vacuum more than those of any other elements in the range 150--350 eV. Because of this, uranium could be used in high reflectance imaging mirrors for soft x-ray applications. Unfortunately, elemental uranium is chemically actrive and readily oxidizes. Uranium nitride is reported to have high density (14.3 g/cm^3) and to be more resistant to oxidation and hydrolysis. We computed the expected reflectance of uranium nitride films for low-angle reflectance. We reactively sputtered uranium in an argon/nitrogen ambient. Samples sputtered at a nitrogen partial pressure of >10-4 torr could be U_2N_3. Measured reflectances of these uranium nitride films (Beamline 6.3.2, ALS at LBNL) do not reach those predicted for UN. Measurements were over the range 80--182 eV and from 0 to 40 degrees grazing incidence. Sample reflectance was twice as great as that of nickel, the material used for low-angle mirrors, but less than that of our UO_x. XPS is being used to determine the composition of the films and we are testing samples deposited at lower nitrogen partial pressures.

  15. Photodissociation of HCN and HNC isomers in the 7-10 eV energy range

    NASA Astrophysics Data System (ADS)

    Chenel, Aurelie; Roncero, Octavio; Aguado, Alfredo; Agúndez, Marcelino; Cernicharo, José

    2016-04-01

    The ultraviolet photoabsorption spectra of the HCN and HNC isomers have been simulated in the 7-10 eV photon energy range. For this purpose, the three-dimensional adiabatic potential energy surfaces of the 7 lowest electronic states, and the corresponding transition dipole moments, have been calculated, at multireference configuration interaction level. The spectra are calculated with a quantum wave packet method on these adiabatic potential energy surfaces. The spectra for the 3 lower excited states, the dissociative electronic states, correspond essentially to predissociation peaks, most of them through tunneling on the same adiabatic state. The 3 higher electronic states are bound, hereafter electronic bound states, and their spectra consist of delta lines, in the adiabatic approximation. The radiative lifetime towards the ground electronic states of these bound states has been calculated, being longer than 10 ns in all cases, much longer that the characteristic predissociation lifetimes. The spectra of HCN is compared with the available experimental and previous theoretical simulations, while in the case of HNC there are no previous studies to our knowledge. The spectrum for HNC is considerably more intense than that of HCN in the 7-10 eV photon energy range, which points to a higher photodissociation rate for HNC, compared to HCN, in astrophysical environments illuminated by ultraviolet radiation.

  16. Transmittance and optical constants of Eu films from 8.3 to 1400 eV

    SciTech Connect

    Fernandez-Perea, Monica; Vidal-Dasilva, Manuela; Aznarez, Jose A.; Larruquert, Juan I.; Mendez, Jose A.; Poletto, Luca; Garoli, Denis; Malvezzi, A. Marco; Giglia, Angelo; Nannarone, Stefano

    2008-12-15

    The optical constants of Eu films were obtained in the 8.3-1400 eV range from transmittance measurements performed at room temperature. Thin films of Eu were deposited by evaporation in ultrahigh vacuum conditions and their transmittance was measured in situ. Eu films were deposited onto grids coated with a thin C support film. The refractive index n of Eu was calculated using the Kramers-Kronig analysis. Data were extrapolated both on the high- and low-energy sides by using experimental and calculated extinction coefficient values available in the literature. Eu, similar to other lanthanides, has a low-absorption band just below the O{sub 2,3} edge onset; the lowest absorption was measured at about 16.7 eV. Therefore, Eu is a promising material for filters and multilayer coatings in the energy range below the O{sub 2,3} edge in which materials typically have a strong absorption. The consistency of the composite optical constants was tested with the f and inertial sum rules and found to be good.

  17. A neutron spectrometer for neutron energies between 1 eV and 10 keV

    SciTech Connect

    Wang, C.K.; Blue, T.E.

    1988-01-01

    In boron neutron capture therapy (BNCT), it is the consensus that epithermal neutron beams have advantages over thermal beams in treating deep-seated brain tumors, and large neutron fields have advantages over narrow beams, since whole-brain irradiations are thought to be necessary in many cases. Epithermal neutron sources for BNCT, which include filtered reactor neutron beams and moderated reactor neutron fields, are currently being developed at many institutions around the world. Neutrons with energies between 1 eV and 10 keV are most suitable for treating brain tumors. However, techniques for measuring neutron spectra in a vacuum in this energy range are not well developed. This paper describes a new type of neutron spectrometer that has a set of response functions that peak at equally spaced intervals on a logarithmic energy scale ranging from 1 eV to 10 keV; therefore, neutron spectra (or histograms) in this energy range can be obtained by properly applying spectrum unfolding techniques to the measured data. The spectrometer is applicable for measurements in a vacuum for both narrow neutron beams and wide neutron fields.

  18. Latency Requirements for Head-Worn Display S/EVS Applications

    NASA Technical Reports Server (NTRS)

    Bailey, Randall E.; Trey Arthur, J. J., III; Williams, Steven P.

    2004-01-01

    NASA s Aviation Safety Program, Synthetic Vision Systems Project is conducting research in advanced flight deck concepts, such as Synthetic/Enhanced Vision Systems (S/EVS), for commercial and business aircraft. An emerging thrust in this activity is the development of spatially-integrated, large field-of-regard information display systems. Head-worn or helmet-mounted display systems are being proposed as one method in which to meet this objective. System delays or latencies inherent to spatially-integrated, head-worn displays critically influence the display utility, usability, and acceptability. Research results from three different, yet similar technical areas flight control, flight simulation, and virtual reality are collectively assembled in this paper to create a global perspective of delay or latency effects in head-worn or helmet-mounted display systems. Consistent definitions and measurement techniques are proposed herein for universal application and latency requirements for Head-Worn Display S/EVS applications are drafted. Future research areas are defined.

  19. Uranium Oxide as a Highly Reflective Coating from 100-400 eV

    SciTech Connect

    Sandberg, Richard L.; Allred, David D.; Bissell, Luke J.; Johnson, Jed E.; Turley, R. Steven

    2004-05-12

    We present the measured reflectances (Beamline 6.3.2, ALS at LBNL) of naturally oxidized uranium and naturally oxidized nickel thin films from 100-460 eV (2.7 to 11.6 nm) at 5 and 15 degrees grazing incidence. These show that uranium, as UO2, can fulfill its promise as the highest known single surface reflector for this portion of the soft x-ray region, being nearly twice as reflective as nickel in the 124-250 eV (5-10 nm) region. This is due to its large index of refraction coupled with low absorption. Nickel is commonly used in soft x-ray applications in astronomy and synchrotrons. (Its reflectance at 10 deg. exceeds that of Au and Ir for most of this range.) We prepared uranium and nickel thin films via DC-magnetron sputtering of a depleted U target and resistive heating evaporation respectively. Ambient oxidation quickly brought the U sample to UO2 (total thickness about 30 nm). The nickel sample (50 nm) also acquired a thin native oxide coating (<2nm). Though the density of U in UO2 is only half of the metal, its reflectance is high and it is relatively stable against further changes.

  20. Photodissociation of HCN and HNC isomers in the 7-10 eV energy range.

    PubMed

    Chenel, Aurelie; Roncero, Octavio; Aguado, Alfredo; Agúndez, Marcelino; Cernicharo, José

    2016-04-14

    The ultraviolet photoabsorption spectra of the HCN and HNC isomers have been simulated in the 7-10 eV photon energy range. For this purpose, the three-dimensional adiabatic potential energy surfaces of the 7 lowest electronic states, and the corresponding transition dipole moments, have been calculated, at multireference configuration interaction level. The spectra are calculated with a quantum wave packet method on these adiabatic potential energy surfaces. The spectra for the 3 lower excited states, the dissociative electronic states, correspond essentially to predissociation peaks, most of them through tunneling on the same adiabatic state. The 3 higher electronic states are bound, hereafter electronic bound states, and their spectra consist of delta lines, in the adiabatic approximation. The radiative lifetime towards the ground electronic states of these bound states has been calculated, being longer than 10 ns in all cases, much longer that the characteristic predissociation lifetimes. The spectra of HCN is compared with the available experimental and previous theoretical simulations, while in the case of HNC there are no previous studies to our knowledge. The spectrum for HNC is considerably more intense than that of HCN in the 7-10 eV photon energy range, which points to a higher photodissociation rate for HNC, compared to HCN, in astrophysical environments illuminated by ultraviolet radiation. PMID:27083720

  1. Small-angle (e-, Na) scattering in the 6-25-eV range

    NASA Astrophysics Data System (ADS)

    Jaduszliwer, B.; Weiss, P.; Tino, A.; Bederson, B.

    1984-09-01

    We have investigated elastic and inelastic scattering of electrons by sodium atoms at intermediate energies (6-25 eV) by the atomic-recoil technique, using a new atomic-beams apparatus. The effects of the apparatus geometry, atomic velocity, and electron energy distributions on the analysis of the experimental results have been examined in detail, and their effects on small-angle scattering have been incorporated into the present work. We present absolute measurements of the elastic (e-, Na) differential cross section at 10 eV for electron polar angles ranging between 12° and 22°. These measurements are in good agreement with the normalized results of S. K. Srivastava and L. Vuskovic

    [J. Phys. B 13, 2633 (1980)]
    and in reasonable agreement with the two-state close-coupling calculation of
    M. R. Issa (Ph.D. theis, University of Durham, 1977)
    . We also present absolute measurements of an integral over small angles of the 32P impact-excitation differential cross section, together with a precise prescription for comparison with theory. We found that the distortedwave-polarized-orbital calculation of J. V. Kennedy, V. P. Myerscough, and M. R. C. McDowell
    [J. Phys. B 10 3759 (1977)]
    gives results which are too high in the forward direction, while those of Issa are somewhat low.

  2. One-milliarsecond precision parallax studies in the regions of Delta Cephei and EV Lacertae

    NASA Technical Reports Server (NTRS)

    Gatewood, George; De Jonge, Kiewiet Joost; Stephenson, Bruce

    1993-01-01

    Trigonometric parallaxes for stars in the regions of the variable stars delta Cephei and EV Lacertae are derived from data collected with the Multichannel Astrometric Photometer (MAP) and the Thaw Refractor of the University of Pittsburgh's Allegheny Observatory. The weighted mean parallax of all trigonometric studies of delta Cephei is now + 0.0030 sec + or - 0.00093 sec, corresponding to a distance modulus of 7.61 + or - 0.67 mag. This indicates that this luminosity standard star is approximately one standard deviation more distance than has been generally accepted. The weighted mean trigonometric parallax of all studies of the variable star EV Lacertae (BD + 43 deg 4305) is + 0.1993 sec + or - 0.00093 sec, implying a distance modulus of - 1.498 + or - 0.0010 mag. The calculated absolute magnitude of this star is almost exactly that predicted by its (R-I)(sub Kron) magnitude and by the Gliese (R-I) main-sequence value for stars in the solar neighborhood. We also find a parallax of 0.0189 sec + or - 0.0008 sec for the FO IVn star, HR 8666 (BD + 43 sec 4300). The derived luminosity of this star is midway between that expected for luminosity class IV and V stars at the indicated temperature.

  3. Depth of maximum of air-shower profiles at the Pierre Auger Observatory. I. Measurements at energies above $$10^{17.8}$$ eV

    DOE PAGESBeta

    Aab, Alexander

    2014-12-31

    We report a study of the distributions of the depth of maximum, Xmax, of extensive air-shower profiles with energies above 1017.8 eV as observed with the fluorescence telescopes of the Pierre Auger Observatory. The analysis method for selecting a data sample with minimal sampling bias is described in detail as well as the experimental cross-checks and systematic uncertainties. Furthermore, we discuss the detector acceptance and the resolution of the Xmax measurement and provide parametrizations thereof as a function of energy. Finally, the energy dependence of the mean and standard deviation of the Xmax distributions are compared to air-shower simulations formore » different nuclear primaries and interpreted in terms of the mean and variance of the logarithmic mass distribution at the top of the atmosphere.« less

  4. Investigation of gamma-ray families originating from nucleus-nucleus interactions at ultrahigh energies E{sub 0} in excess of 10{sup 16} eV

    SciTech Connect

    Yuldashbaev, T. S.; Nuritdinov, Kh.

    2013-12-15

    Various spatial and energy features of gamma-ray families originating from the interactions of primary nuclei of galactic cosmic rays with nuclei of atmospheric atoms (AA interactions) are studied. The mass composition of galactic cosmic rays is analyzed on the basis of data from x-ray emulsion chambers of the Pamir experiment with the aid of a criterion for selecting gamma-ray families originating from AA interactions (A families) at energies E{sub 0} of primary galactic cosmic rays in excess of 10{sup 16} eV. According to the results obtained in this way only the experimental spatial parameters R{sub 1E} and ρ differ from their counterparts in the MC0 model.

  5. Depth of maximum of air-shower profiles at the Pierre Auger Observatory. I. Measurements at energies above $10^{17.8}$ eV

    SciTech Connect

    Aab, Alexander

    2014-12-31

    We report a study of the distributions of the depth of maximum, Xmax, of extensive air-shower profiles with energies above 1017.8 eV as observed with the fluorescence telescopes of the Pierre Auger Observatory. The analysis method for selecting a data sample with minimal sampling bias is described in detail as well as the experimental cross-checks and systematic uncertainties. Furthermore, we discuss the detector acceptance and the resolution of the Xmax measurement and provide parametrizations thereof as a function of energy. Finally, the energy dependence of the mean and standard deviation of the Xmax distributions are compared to air-shower simulations for different nuclear primaries and interpreted in terms of the mean and variance of the logarithmic mass distribution at the top of the atmosphere.

  6. Neutrino mass from the beta spectrum in the decay of tritium

    SciTech Connect

    Boris, S.; Golutvin, A.; Laptin, L.; Lubimov, V.; Nagovizin, V.; Nozik, V.; Novikov, E.; Soloshenko, V.; Tihomirov, I.; Tretjakov, E.; and others

    1987-05-18

    The data from the spectrum measurement of the tritium decay in a valine molecule carried out in a wide energy range (3.4 KeV) with the ITEP spectrometer are analyzed. The combined analysis of both these data and the data of the previous cycle gives the neutrino mass 30.3/sub -8//sup +2/ eV. The model-independent mass interval 17eV is derived from the mass difference of the doublet /sup 3/H-/sup 3/He.

  7. Development of 1.25 eV InGaAsN for triple junction solar cells

    SciTech Connect

    LI,N.Y.; SHARPS,P.R.; HILLS,J.S.; HOU,H.; CHANG,PING-CHIH; BACA,ALBERT G.

    2000-05-16

    Development of next generation high efficiency space monolithic multifunction solar cells will involve the development of new materials lattice matched to GaAs. One promising material is 1.05 eV InGaAsN, to be used in a four junction GaInP{sub 2}/GaAs/InGaAsN/Ge device. The AMO theoretical efficiency of such a device is 38--42%. Development of the 1.05 eV InGaAsN material for photovoltaic applications, however, has been difficult. Low electron mobilities and short minority carrier lifetimes have resulted in short minority carrier diffusion lengths. Increasing the nitrogen incorporation decreases the minority carrier lifetime. The authors are looking at a more modest proposal, developing 1.25 eV InGaAsN for a triple junction GaInP{sub 2}/InGaAsN/Ge device. The AMO theoretical efficiency of this device is 30--34%. Less nitrogen and indium are required to lower the bandgap to 1.25 eV and maintain the lattice matching to GaAs. Hence, development and optimization of the 1.25 eV material for photovoltaic devices should be easier than that for the 1.05 eV material.

  8. A functional polymorphism in IFNAR1 gene is associated with susceptibility and severity of HFMD with EV71 infection.

    PubMed

    Zou, Rongrong; Zhang, Guoliang; Li, Shaoyuan; Wang, Wenfei; Yuan, Jing; Li, Jianming; Wang, Yanrong; Lin, Yimin; Deng, Yong; Zhou, Boping; Gao, George Fu; Liu, Yingxia

    2015-01-01

    Enterovirus 71 (EV71), one of the major pathogens of Hand, foot and mouth disease (HFMD), results in millions of infections and hundreds of deaths each year in Southeast Asia. Biased infection and variable clinical manifestations of EV71 HFMD indicated that host genetic background played an important role in the occurrence and development of the disease. We identified the mRNA profiles of EV71 HFMD patients, which type I interferon (IFN) pathway related genes were down-regulated. Four single nucleotide polymorphisms (SNPs) of type I IFN receptor 1 (IFNAR1) were chosen to analyze their relationships to EV71 infection. We found that genotype GG of promoter variant rs2843710 was associated with the susceptibility and severity to EV71 HFMD. In addition, we assessed the regulatory effects of rs2843710 to IFN stimulated genes (ISGs), and found that the expressions of IFNAR1, OAS1 and MX1 were significantly lower in patients with rs2843710 genotype GG. And rs2843710 allele G showed weaker transcriptional activity compared with allele C. Our study indicated that rs2843710 of IFNAR1 was associated with the susceptibility and severity of EV71 HFMD in Chinese Han populations, acting as a functional polymorphism by regulating ISGs expression, such as OAS1 and MX1. PMID:26679744

  9. Out-of-plane (e , 2 e) measurements on He autoionizing levels at 80, 150, and 488 eV

    NASA Astrophysics Data System (ADS)

    Martin, N. L. S.; Kim, B. N.; Weaver, C. M.; Deharak, B. A.; Bartschat, K.

    2016-05-01

    We report out-of-scattering-plane (e , 2 e) measurements on helium 2 l 2l' autoionizing levels for 80, 150, and 488 eV incident electron energies, and scattering angles 60°, 39. 2°, and 20. 5°, respectively. The kinematics are the same in all cases: ejected electrons are detected in a plane that contains the momentum transfer direction and is perpendicular to the scattering plane, and the momentum transfer is 2.1 a.u.. The 80 eV results complete our sets of measurements at low, intermediate, and high, incident energies. The results are presented as (e , 2 e) angular distributions energy-integrated over each level, and are compared with our theory calculated for 488 eV incident electron energy. The 150 eV and 488 eV experiments are characterized by recoil peaks appropriate to each autoionizing level. However, for the 80 eV angular distributions, these recoil peaks are largely absent for all levels, including the 3 P level observed at this energy. This work was supported by the National Science Foundation under Grants Nos. PHY-0855040 (NLSM), PHY-1402899 (BAdH), and PHY-1212450 (KB).

  10. A functional polymorphism in IFNAR1 gene is associated with susceptibility and severity of HFMD with EV71 infection

    PubMed Central

    Zou, Rongrong; Zhang, Guoliang; Li, Shaoyuan; Wang, Wenfei; Yuan, Jing; Li, Jianming; Wang, Yanrong; Lin, Yimin; Deng, Yong; Zhou, Boping; Gao, George Fu; Liu, Yingxia

    2015-01-01

    Enterovirus 71 (EV71), one of the major pathogens of Hand, foot and mouth disease (HFMD), results in millions of infections and hundreds of deaths each year in Southeast Asia. Biased infection and variable clinical manifestations of EV71 HFMD indicated that host genetic background played an important role in the occurrence and development of the disease. We identified the mRNA profiles of EV71 HFMD patients, which type I interferon (IFN) pathway related genes were down-regulated. Four single nucleotide polymorphisms (SNPs) of type I IFN receptor 1 (IFNAR1) were chosen to analyze their relationships to EV71 infection. We found that genotype GG of promoter variant rs2843710 was associated with the susceptibility and severity to EV71 HFMD. In addition, we assessed the regulatory effects of rs2843710 to IFN stimulated genes (ISGs), and found that the expressions of IFNAR1, OAS1 and MX1 were significantly lower in patients with rs2843710 genotype GG. And rs2843710 allele G showed weaker transcriptional activity compared with allele C. Our study indicated that rs2843710 of IFNAR1 was associated with the susceptibility and severity of EV71 HFMD in Chinese Han populations, acting as a functional polymorphism by regulating ISGs expression, such as OAS1 and MX1. PMID:26679744

  11. Measurements of Lyman Alpha Radiation from Collisions, 100 EV to 4000EV, of Negative Hydrogen Ions on Various Target Gases and Positive Hydrogen Ions on Xenon

    NASA Astrophysics Data System (ADS)

    Greenland, Glenn Blair

    This study reports measurements of cross sections for the production of Lyman alpha radiation from processes in which an ion is incident on a neutral target gas. Two kinds of processes were measured: the stripping of the extra electron from a negative hydro- gen ion leaving an excited neutral and the capture of an electron by a proton also leaving an excited neutral. In each case, radiation from the 2p state of the neutral hydrogen was detected. The projectile struck the static gas target with a kinetic energy between 100 and 4000 electron volts. The measurements used the ultraviolet absorption properties of molecular oxygen to isolate the Lyman alpha line. Cross sections for emission of Lyman alpha perpendicular to the incident beam were determined. The targets used in the stripping experiments were the atomic gases: helium, neon, argon, krypton and xenon, and the molecular gases: hydrogen, nitrogen and methane. The cross sections are rela- tively flat over the energy range investigated. All are slightly below 10('-16) cm('2) at 1000 eV. Only with the neon target does the cross section fall below 2 x 10('0-17) cm('2) at 100 electron volts. While the data appear to support the modeling of stripping with excitation as a two step process, this modeling may not be valid for excitation above 2p. Only a xenon target was used in the capture experiments. Careful measurements did not substantiate an earlier report of unusual structure('1) in this cross section. ('1)P. J. Martin, Ph.D. Dissertation, Univ. of Nebraska, 1975.

  12. Inertial Mass

    ERIC Educational Resources Information Center

    King, Kenneth P.

    2007-01-01

    The inertial balance is one device that can help students to quantify the quality of inertia--a body's resistance to a change in movement--in more generally understood terms of mass. In this hands-on activity, students use the inertial balance to develop a more quantitative idea of what mass means in an inertial sense. The activity also helps…

  13. Experiment to measure the electron neutrino mass using frozen tritium

    SciTech Connect

    Fackler, O.; Sticker, H.; Mugge, M.; White, R.M.; Woerner, R.

    1985-01-01

    We are performing an experiment to determine the electron neutrino mass with the precision of a few eV by measuring the tritium beta decay energy distribution near the endpoint. To make this measurement, we have built a spectrometer with a resolution of 2 eV. Our source is frozen tritium since tritium and the HeT/sup +/ daughter ion have electronic wavefunctions that can be calculated with high accuracy. We describe the experiment and discuss the excited final molecular state calculations.

  14. Statistical survey of pitch angle distributions in core (0-50 eV) ions from Dynamics Explorer 1: Outflow in the auroral zone, polar cap, and cusp

    NASA Technical Reports Server (NTRS)

    Giles, B. L.; Chappell, C. R.; Moore, T. E.; Comfort, R. H.; Waite, J. H., Jr.

    1994-01-01

    Core (0-50 eV) ion pitch angle measurements from the retarding ion mass spectrometer on Dynamics Explorer 1 are examined with respect to magnetic disturbance, invariant latitude, magnetic local time, and altitude for ions H(+), He(+), O(+), M/Z = 2 (D(+) or He(++)), and O(++). Included are outflow events in the auroral zone, polar cap, and cusp, separated into altitude regions below and above 3 R(sub E). In addition to the customary division into beam, conic, and upwelling distributions, the high-latitude observations fall into three categories corresponding to ion bulk speeds that are (1) less than, (2) comparable to, or (3) faster than that of the spacecraft. This separation, along with the altitude partition, serves to identify conditions under which ionospheric source ions are gravita- tionally bound and when they are more energetic and able to escape to the outer magnetosphere. Features of the cleft ion fountain inferred from single event studies are clearly identifiable in the statistical results. In addition, it is found that the dayside pre-noon cleft is a dayside afternoon cleft, or auroral zone, becomes an additional source for increased activity. The auroral oval as a whole appears to be a steady source of escape velocity H(+), a steady source of escape velocity He(+) ions for the dusk sector, and a source of escape velocity heavy ions for dusk local times primarily during increased activity. The polar cap above the auroral zone is a consistent source of low-energy ions, although only the lighter mass particles appear to have sufficient velocity, on average, to escape to higher altitudes. The observations support two concepts for outflow: (1) The cleft ion fountain consists of ionospheric plasma of 1-20 eV energy streaming upward into the magnetosphere where high-latitude convection electric fields cause poleward dispersion. (2) The auroral ion fountain involves field-aligned beams which flow out along auroral latitude field lines; and, in addition, for

  15. Simple neutrino mass matrix with only two free parameters

    NASA Astrophysics Data System (ADS)

    Nishiura, Hiroyuki; Fukuyama, Takeshi

    2014-09-01

    A simple form of neutrino mass matrix which has only two free parameters is proposed from a phenomenological point of view. Using this mass matrix, we succeed to reproduce all the observed values for the Maki-Nakagawa-Sakata (MNS) lepton mixing angles and the neutrino mass squared difference ratio. Our model also predicts δν = 155° for the Dirac CP violating phase in the lepton sector and the effective neutrino mass = 6.3×10-3eV in the neutrinoless double beta decay.

  16. Neutrino masses in the economical 3-3-1 model

    SciTech Connect

    Dong, P. V.; Long, H. N.; Soa, D. V.

    2007-04-01

    We show that in the framework of the economical 3-3-1 model, the suitable pattern of neutrino masses arises from three quite different sources - the lepton-number conserving, the spontaneous lepton-number breaking, and the explicit lepton-number violating, widely ranging over mass scales including the GUT one: u{approx}O(1) GeV, v{approx_equal}246 GeV, {omega}{approx}O(1) TeV, and M{approx}O(10{sup 16}) GeV. At the tree level, the model contains three Dirac neutrinos: one massless, and two large with degenerate masses in the range of the electron mass. At the one-loop level, the left-handed and right-handed neutrinos obtain Majorana masses M{sub L,R} in orders of 10{sup -2}-10{sup -3} eV and degenerate in M{sub R}=-M{sub L}, while the Dirac masses get a large reduction down to eV scale through a finite mass renormalization. In this model, the contributions of new physics are strongly signified, the degenerations in the masses and the last hierarchy between the Majorana and Dirac masses can be completely removed by heavy particles. All the neutrinos get mass and can fit the data. The acceptable set of the input data does not induce the large lepton flavor violating branching ratios such as Br({mu}{yields}e{gamma})

  17. Atomic Masses of Tritium and Helium-3

    NASA Astrophysics Data System (ADS)

    Myers, E. G.; Wagner, A.; Kracke, H.; Wesson, B. A.

    2015-01-01

    By measuring the cyclotron frequency ratios of 3He+ to HD+ and T+ to HD+ , and using HD+ as a mass reference, we obtain new atomic masses for 3He and T. Our results are M [3He]=3.016 029 322 43 (19 ) u and M [T ]=3.016 049 281 78 (19 ) u , where the uncertainty includes an uncertainty of 0.12 nu in the mass reference. Allowing for cancellation of common systematic errors, we find the Q value for tritium β decay to be (M [T ]-M [3He])c2=18 592.01 (7 ) eV . This allows an improved test of systematics in measurements of tritium β decay that set limits on neutrino mass.

  18. IGSN e.V.: Registration and Identification Services for Physical Samples in the Digital Universe

    NASA Astrophysics Data System (ADS)

    Lehnert, K. A.; Klump, J.; Arko, R. A.; Bristol, S.; Buczkowski, B.; Chan, C.; Chan, S.; Conze, R.; Cox, S. J.; Habermann, T.; Hangsterfer, A.; Hsu, L.; Milan, A.; Miller, S. P.; Noren, A. J.; Richard, S. M.; Valentine, D. W.; Whitenack, T.; Wyborn, L. A.; Zaslavsky, I.

    2011-12-01

    -for-profit organization, the IGSN e.V. (e.V. = 'Eingetragener Verein', legal status for a registered voluntary association in Germany), that defines the IGSN scope and syntax and maintains the IGSN Handle system, and (b) a Science Advisory Board that guides policies, technology, and best practices of the SESAR Sample Metadata Clearinghouse and Local Registration Agents. The IGSN e.V. is being incorporated in Germany at the GFZ Potsdam, a founding event is planned for the AGU Fall Meeting.

  19. Direct Measurement of the Mass Difference of (163)Ho and (163)Dy Solves the Q-Value Puzzle for the Neutrino Mass Determination.

    PubMed

    Eliseev, S; Blaum, K; Block, M; Chenmarev, S; Dorrer, H; Düllmann, Ch E; Enss, C; Filianin, P E; Gastaldo, L; Goncharov, M; Köster, U; Lautenschläger, F; Novikov, Yu N; Rischka, A; Schüssler, R X; Schweikhard, L; Türler, A

    2015-08-01

    The atomic mass difference of (163)Ho and (163)Dy has been directly measured with the Penning-trap mass spectrometer SHIPTRAP applying the novel phase-imaging ion-cyclotron-resonance technique. Our measurement has solved the long-standing problem of large discrepancies in the Q value of the electron capture in (163)Ho determined by different techniques. Our measured mass difference shifts the current Q value of 2555(16) eV evaluated in the Atomic Mass Evaluation 2012 [G. Audi et al., Chin. Phys. C 36, 1157 (2012)] by more than 7σ to 2833(30(stat))(15(sys)) eV/c(2). With the new mass difference it will be possible, e.g., to reach in the first phase of the ECHo experiment a statistical sensitivity to the neutrino mass below 10 eV, which will reduce its present upper limit by more than an order of magnitude. PMID:26296112

  20. Vacuum arc plasma mass separator

    NASA Astrophysics Data System (ADS)

    Paperny, V. L.; Krasov, V. I.; Lebedev, N. V.; Astrakchantsev, N. V.; Chernikch, A. A.

    2015-02-01

    The propagation of a metal plasma flow in a transport system with a curvilinear magnetic field was studied experimentally. The flow was generated by a pulsed vacuum arc discharge with a composite (W+Fe) cathode. The ion energy measurements at the transport system output showed that all ion components were accelerated up to equal energies per charge unit, about 150 eV and 320 eV in the outer and inner areas of the curved plasma flow, respectively. The spatial separation of the atoms of the cathode material was measured at the system output by x-ray fluorescence spectrometry. The ions of the lighter element (Fe) were concentrated in the inner part of the cathodic plasma flow deflected by the magnetic field while the distribution of the heavy element (W) was substantially shifted toward the outer area of the flow. The maximum mass separation efficiency reached 45, the effective value being 7.7. Such a system is promising for use in plasma technology for reprocessing spent nuclear fuel, namely for the separation of the heavy radioactive fission product from nuclear waste.

  1. EV-16 vitrification demonstration with surrogate Oak Ridge reservation K-25 B & C pond sludge

    SciTech Connect

    Cicero, C.A.

    1996-07-05

    The Mixed Waste Focus Area (MWFA) has chartered the Savannah River Technology Center (SRTC) to design and fabricate a Transportable Vitrification System (TVS) to demonstrate treatment of Low-Level Mixed Waste (LLMW). This system will be used to demonstrate the feasibility of vitrification on several LLMW streams. The first stream to be demonstrated will be the Oak Ridge Reservation (ORR) K-25 B&C Pond sludge. Before the demonstrations in the TVS can take place, a surrogate sludge vitrification demonstration had to be performed in the EV-16 melter located at the DOE Industrial Center for Vitrification Research (Center) at the Environmental Systems Engineering Department at Clemson University. During the demonstration at the Center, a 50 wt% B&C sludge glass composition was tested to determine any processing problems. A total of 1510 pounds (686 kg) of glass were produced from 9328 pounds (4240 kg) of surrogate feed. The resulting glass product was homogeneous and very durable.

  2. Synthesis of cubic boron nitride films with mean ion energies of a few eV

    SciTech Connect

    Teii, Kungen; Yamao, Ryota; Yamamura, Toshifumi; Matsumoto, Seiichiro

    2007-02-01

    The lowest threshold energy of ion bombardment for cubic boron nitride (cBN) film deposition is presented. cBN films are prepared on positively biased Si (100) substrates from boron trifluoride (BF{sub 3}) gas in the high-density source region of an inductively coupled plasma with mean ion impact energies from 45 down to a few eV or less. The great decrease in the threshold ion energy is mainly attributed to specific chemical effects of fluorine as well as high ion-to-boron flux ratios. The results show evidence for the existence of a way to deposit cBN films through quasistatic chemical processes under ultralow-energy ion impact.

  3. The Advanced Light Source U8 beam line, 20--300 eV

    SciTech Connect

    Heimann, P.; Warwick, T.; Howells, M.; McKinney, W.; Digennaro, D.; Gee, B.; Yee, D.; Kincaid, B.

    1991-10-01

    The U8 is a beam line under construction at the Advanced Light Source (ALS). The beam line will be described along with calculations of its performance and its current status. An 8 cm period undulator is followed by two spherical collecting mirrors, an entrance slit, spherical gratings having a 15{degree} deviation angle, a moveable exit slit, and refocusing and branching mirrors. Internal water cooling is provided to the metal M1 and M2 mirrors as well as to the gratings. Calculations have been made of both the flux output and the resolution over its photon energy range of 20--300 eV. The design goal was to achieve high intensity, 10{sup 12} photons/sec, at a high resolving power of 10,000. The U8 Participating Research Team (PRT) is planning experiments involving the photoelectron spectroscopy of gaseous atoms and molecules, the spectroscopy of ions and actinide spectroscopy.

  4. The cosmic ray spectrum above 10(19) EV at Volcano Ranch and Haverah Park

    NASA Technical Reports Server (NTRS)

    Linsley, J.

    1986-01-01

    The cosmic ray energy per particle spectrum above 10 to the 19th power eV is measured the same way that energy spectra are measured at much lower energies, by counting all of the particles in a specified energy range that are incident per unit time with trajectories within specified geometrical limits. Difficulties with background or poorly known detection efficiency are markedly less than in some other cosmic ray measurements. The fraction of primary energy given to muons, neutrinos, and slow hadrons is less than 10% in this region, so the primary energy equals the track length integral of the secondary electrons with only a small correction for the energy given to other kinds of particles. Results from Volcano Ranch and Haverah Park are compared with results from the Yakutsk experiment.

  5. Testing and evaluation of EV-1300 lead-acid modules for the hybrid vehicle application

    SciTech Connect

    Gay, E.C.; Webster, C.E.; Hornstra, F.; Yao, N.P.

    1984-01-01

    This paper presents the results of testing and evaluation of GE/Globe EV-1300 lead-acid modules developed by Globe Battery Division of Johnson Controls, Inc. for the hybrid vehicle, HTV-I, developed by General Electric (GE) for the Department of Energy. The design of this battery was derived from that of the Globe Improved State of the Art (ISOA) battery under development for the ETV-1 all-electric vehicle. Key differences in the battery performance requirements for the HTV-1 hybrid vehicle, as opposed to the ETV-1, are higher specific power (137 W/kg versus 104 W/kg sustained for 15 seconds at 50% depth of discharge (DOD)) and less specific energy (36.1 Wh/kg versus 37.5 Wh/kg at a 3h discharge rate).

  6. Extensive Air Showers and Cosmic Ray Physics above 1017 eV

    NASA Astrophysics Data System (ADS)

    Bertaina, Mario

    2016-07-01

    Cosmic Rays above 1017 eV allow studying hadronic interactions at energies that can not be attained at accelerators yet. At the same time hadronic interaction models have to be applied to the cosmic-ray induced air-shower cascades in atmosphere to infer the nature of cosmic rays. The reliability of air-shower simulations has become the source of one of the largest systematic uncertainty in the interpretation of cosmic-ray data due to the uncertainties in modeling the hadronic interaction driving the air-shower development. This paper summarises in the first part the recent results on the cosmic ray energy spectrum, composition and anisotropy from the knee region to the GZK cutoff [1, 2] of the spectrum by means of ground-based experiments. Most of the information reported in this contribution is taken from [3-5]. Aspects interconnecting cosmic ray and particle physics are reviewed in the second part of the paper.

  7. Electron impact excitation of 5p states of rubidium at 20 eV incident energy

    NASA Astrophysics Data System (ADS)

    Hou Chin, Jia; Ratnavelu, Kuru; Zhou, Yajun

    2014-06-01

    The coupled-channel optical method (CCOM) is implemented in this work to study the scattering of electron on rubidium atom at 20 eV. In order to provide a realistic calculation, the continuum effect of the scattering system is accounted by incorporate an ab initio optical potential into the CCOM calculation. The differential cross sections (DCS), as well as the reduced Stokes parameters of 5p excitation are reported and compared to the available experimental and theoretical data. Contribution to the Topical Issue "Electron and Positron Induced Processes", edited by Michael Brunger, Radu Campeanu, Masamitsu Hoshino, Oddur Ingólfsson, Paulo Limão-Vieira, Nigel Mason, Yasuyuki Nagashima and Hajime Tanuma.

  8. The flare star EV Lac. II - Relations between the characteristics of the flares

    NASA Astrophysics Data System (ADS)

    Avgoloupis, S.

    1986-07-01

    Characteristics of the four types of flares observed during the 184 events that were observed on the flare star EV Lac in the period 1967-1980 are analyzed. The data include the duration and magnitude of each event, the mean rate of luminosity and apparent magnitude increases, the integrated flare intensity over the whole event, and time histograms of intensity levels of the events. The flares were distributed into 49 type IV events, 71 type III events, 38 type II events and 25 type I events. Intensities were highest in type II events, and the extremes of other distinguishing characteristics were distributed among the other events, with some having correlations exceeding the 95 percent level. The differences were sufficiently pronounced to conclude that the individual type of flare event must be considered in future analyses, rather than considering all flare events as a uniform database.

  9. Electrochemical efficiency in multiple discharge/recharge cycling of supercapacitors in hybrid EV applications

    NASA Astrophysics Data System (ADS)

    Pell, Wendy G.; Conway, Brian E.; Adams, William A.; de Oliveira, Julio

    The use of large capacitance supercapacitors in series or series/parallel configurations has been envisaged and evaluated as a basis for load-levelling, and hence performance enhancement, in electric vehicles (EV) powered primarily by rechargeable batteries or fuel-cells. In this paper, charge/discharge efficiency in duty-cycles of the supercapacitor component are examined in relation to distributed resistance in porous double-layer and redox-type devices which restricts efficiency of discharge and recharge cycling, especially at high rates. Results of quantitative experiments on the responses of a five-element RC model hardware equivalent-circuit and a gold brush electrode are presented. Potential-recovery after discharge and potential-decay after recharge, and potential changes following load variations, enable efficiencies of charge delivery and acceptance to be evaluated.

  10. Electron Landau damping in toroidal plasma with Solov’ev equilibrium

    SciTech Connect

    Grishanov, N. I. Azarenkov, N. A.

    2013-12-15

    The contribution of untrapped and two groups of trapped particles to the longitudinal (with respect to the magnetic field) elements of the dielectric susceptibility is determined by solving the drift-kinetic equations for such particles in axisymmetric tokamaks with Solov’ev equilibrium. The obtained dielectric characteristics are applicable for studying linear wave processes in the frequency range of Alfvén and fast magnetosonic waves in small- and large-aspect-ratio tokamaks with circular, elliptical, and D-shaped cross sections of magnetic surfaces. The high-frequency power absorbed in plasma via electron Landau damping is estimated by summing up terms containing the imaginary parts of both diagonal and non-diagonal elements of the longitudinal susceptibility. The imaginary part of the longitudinal susceptibility is calculated numerically for spherical tokamaks in a wide range of wave frequencies and magnetic surface radii.

  11. Integrated Charger with Wireless Charging and Boost Function for PHEV and EV Applications

    SciTech Connect

    Chinthavali, Madhu Sudhan; Onar, Omer C; Campbell, Steven L; Tolbert, Leon M

    2015-01-01

    Integrated charger topologies that have been researched so far with dc-dc converters and the charging functionality have no isolation in the system. Isolation is an important feature that is required for user interface systems that have grid connections and therefore is a major limitation that needs to be addressed along with the integrated functionality. The topology proposed in this paper is a unique and a first of its kind topology that integrates a wireless charging system and the boost converter for the traction drive system. The new topology is also compared with an on-board charger system from a commercial electric vehicle (EV). The ac-dc efficiency of the proposed system is 85.1% and the specific power and power density of the onboard components is ~455 W/kg and ~320 W/ .

  12. Integrated Charger with Wireless Charging and Boost Function for PHEV and EV Applications

    SciTech Connect

    Chinthavali, Madhu Sudhan; Onar, Omer C; Campbell, Steven L

    2015-01-01

    Integrated charger topologies that have been researched so far with dc-dc converters and the charging functionality have no isolation in the system. Isolation is an important feature that is required for user interface systems that have grid connections and therefore is a major limitation that needs to be addressed along with the integrated functionality. The topology proposed in this paper is a unique and a first of its kind topology that integrates a wireless charging system and the boost converter for the traction drive system. The new topology is also compared with an on-board charger system from a commercial electric vehicle (EV). The ac-dc efficiency of the proposed system is 85.05% and the specific power and power density of the onboard components is ~455 W/kg and ~302 W/ .

  13. A method to improve observations of gamma-ray sources near 10 (15) eV

    NASA Technical Reports Server (NTRS)

    Sommers, P.; Elbert, J. W.

    1985-01-01

    Now that sources of gamma rays near 10 to the 15th power eV have been identified, there is a need for telescopes which can study in detail the high energy gamma ray emissions from these sources. The capabilities of a Cerenkov detector which can track a source at large zenith angle (small elevation angle) are analyzed. Because the observed showers must then develop far from the detector, the effective detection area is very large. During a single half-hour hot phase of Cygnus X-3, for example, it may be possible to detect 45 signal showers compared with 10 background showers. Time structure within the hot phase may then be discernible. The precise capabilities of the detector depend on its mirror size, angular acceptance, electronic speed, coincidence properties, etc. Calculations are presented for one feasible design using mirrors of an improved Fly's Eye type.

  14. Mass Deacidification.

    ERIC Educational Resources Information Center

    Harris, Carolyn

    1979-01-01

    Reviews methods being developed for mass deacidification of books to prevent deterioration of paper. The use of diethyl zinc, liquified gas, and morpholine, and the advantages, disadvantages, and cost of each are considered. A 26-item bibliography is included. (JD)

  15. Cosmological bounds on sub-MeV mass axions

    SciTech Connect

    Cadamuro, Davide; Raffelt, Georg; Redondo, Javier; Hannestad, Steen E-mail: sth@phys.au.dk E-mail: redondo@mppmu.mpg.de

    2011-02-01

    Axions with mass m{sub a} ∼> 0.7 eV are excluded by cosmological precision data because they provide too much hot dark matter. While for m{sub a} ∼> 20 eV the a → 2γ lifetime drops below the age of the universe, we show that the cosmological exclusion range can be extended to 0.7eV ∼< m{sub a} ∼< 300 keV, primarily by the cosmic deuterium abundance: axion decays would strongly modify the baryon-to-photon ratio at BBN relative to the one at CMB decoupling. Additional arguments include neutrino dilution relative to photons by axion decays and spectral CMB distortions. Our new cosmological constraints complement stellar-evolution and laboratory bounds.

  16. Morphine analgesic tolerance in 129P3/J and 129S6/SvEv mice

    PubMed Central

    Bryant, Camron D.; Roberts, Kristofer W.; Byun, Janet S.; Fanselow, Michael S.; Evans, Christopher J.

    2007-01-01

    Morphine analgesic tolerance is heritable in both humans and rodents, with some individuals and strains exhibiting little and others exhibiting robust tolerance. 129S6/SvEv and 129P3/J mice reportedly do not demonstrate tolerance to morphine analgesia. Using our laboratory's standard morphine tolerance regimen and a between-subjects design, tolerance developed in the hot plate and tail withdrawal assays as indicated by a change in analgesic efficacy following a morphine challenge dose. Furthermore, the non-competitive NMDA receptor antagonist MK-801 (dizocilipine) blocked morphine tolerance in 129S6/SvEv and CD-1 mice in the hot plate assay. As previously reported, when a within-subjects design and cumulative dosing was employed, no tolerance was observed in the 129P3/J strain. However, using the same morphine regimen and a between-subjects design, comparable tolerance developed between 129P3/J and C57BL/6J strains following a single challenge dose of morphine. Spontaneous hyperalgesia was observed in the tail withdrawal assay following chronic morphine in C57BL/6J, but not 129P3/J mice. Additionally, morphine-tolerant C57BL/6J mice, but not 129P3/J mice, exhibited a large increase in the frequency of tail flicks during the first second following the baseline nociceptive response which may facilitate detection of the response during the tolerant state. We conclude that the method of tolerance assessment affects the ability to detect tolerance and thus, may affect the degree and pattern of heritability of this trait and this could have implications for gene mapping studies. PMID:17196637

  17. Identification of immunodominant VP1 linear epitope of enterovirus 71 (EV71) using synthetic peptides for detecting human anti-EV71 IgG antibodies in Western blots.

    PubMed

    Foo, D G W; Ang, R X; Alonso, S; Chow, V T K; Quak, S H; Poh, C L

    2008-03-01

    A major IgG-specific immunodominant VP1 linear epitope of enterovirus 71 (EV71) strain 41 (5865/SIN/00009), defined by the core sequence LEGTTNPNG, was identified by Pepscan analysis. Oligonucleotides corresponding to the amino-acid sequence of synthetic peptide SP32 were cloned and over-expressed in Escherichia coli as a recombinant glutathione-S-transferase (GST)-SP32 fusion protein. In ELISAs, this protein did not react with human anti-EV71 IgG antibodies, but there was significant immunoreactivity according to western blot analysis. The amino-acid sequence of SP32 was highly specific for detecting EV71 strains in western blot analysis, and showed no immunoreactivity with monoclonal antibodies raised against other enteroviruses, e.g., CA9 and Echo 6. PMID:18076666

  18. Electron impact excitation of the electronic states of N2. III - Transitions in the 12.5-14.2-eV energy-loss region at incident energies of 40 and 60 eV

    NASA Technical Reports Server (NTRS)

    Chutjian, A.; Trajmar, S.; Cartwright, D. C.

    1977-01-01

    Analysis of electron energy-loss data at incident electron energies of 40 and 60 eV has led to the determination of normalized absolute differential cross sections for electron-impact excitation of five optically-allowed singlet states, two known triplet states, and two unknown triplet-like states of N2, lying in the energy-loss range 12.5-14.2 eV. The range of scattering angles was 5 to 138 deg. The optically allowed transitions and the known triplet excitations are identified. Cross sections for excitation to two unidentified triplet-like states at 13.155 and 13.395 eV were also obtained. The relationship of the generalized oscillator strength for the dipole-allowed states obtained from the described data to known optical oscillator strengths is discussed.

  19. A new animal model containing human SCARB2 and lacking stat-1 is highly susceptible to EV71.

    PubMed

    Liou, An-Ting; Wu, Szu-Yao; Liao, Chun-Che; Chang, Ya-Shu; Chang, Chih-Shin; Shih, Chiaho

    2016-01-01

    Enterovirus 71 (EV71) is a major threat to children worldwide. Children infected with EV71 could develop subclinical infection and hand-foot-and -mouth disease (HFMD). In severe cases, patients could develop encephalitis, paralysis, pulmonary edema, and death. A more user-friendly and robust animal model is essential to investigating EV71 pathogenesis. Here, we established a hybrid (hSCARB2(+/+)/stat-1(-/-)) mouse strain from crossbreeding SCARB2 transgenic and stat-1 KO mice, and compared the susceptibilities to EV71 infection and pathogenesis between parental and hybrid mice. Virus-encoded VP1 protein can be detected in the streaking nerve fibers in brain and spinal cord. This hybrid mouse strain at 2-week-old age can still be infected with different genotypes of EV71 at 1000-fold lower titer via an ip route. Infected hybrid mice developed earlier onset of CNS disease, paralysis, and death at a higher incidence. These advantages of this novel model meet the urgent need from the scientific community in basic and preclinical research in therapeutics and pathogenesis. PMID:27499235

  20. A new animal model containing human SCARB2 and lacking stat-1 is highly susceptible to EV71

    PubMed Central

    Liou, An-Ting; Wu, Szu-Yao; Liao, Chun-Che; Chang, Ya-Shu; Chang, Chih-Shin; Shih, Chiaho

    2016-01-01

    Enterovirus 71 (EV71) is a major threat to children worldwide. Children infected with EV71 could develop subclinical infection and hand-foot-and -mouth disease (HFMD). In severe cases, patients could develop encephalitis, paralysis, pulmonary edema, and death. A more user-friendly and robust animal model is essential to investigating EV71 pathogenesis. Here, we established a hybrid (hSCARB2+/+/stat-1−/−) mouse strain from crossbreeding SCARB2 transgenic and stat-1 KO mice, and compared the susceptibilities to EV71 infection and pathogenesis between parental and hybrid mice. Virus-encoded VP1 protein can be detected in the streaking nerve fibers in brain and spinal cord. This hybrid mouse strain at 2-week-old age can still be infected with different genotypes of EV71 at 1000-fold lower titer via an ip route. Infected hybrid mice developed earlier onset of CNS disease, paralysis, and death at a higher incidence. These advantages of this novel model meet the urgent need from the scientific community in basic and preclinical research in therapeutics and pathogenesis. PMID:27499235

  1. Genomic and immunologic factors associated with viral pathogenesis in a lethal EV71 infected neonatal mouse model.

    PubMed

    Yue, Yingying; Li, Peng; Song, Nannan; Li, Bingqing; Li, Zhihui; Guo, Yuqi; Zhang, Weidong; Wei, Ming Q; Gai, Zhongtao; Meng, Hong; Wang, Jiwen; Qin, Lizeng

    2016-05-01

    Hand, foot and mouth disease (HFMD) caused by enterovirus 71 (EV71) has emerged as a major health problem in China and worldwide. The present study aimed to understand the virological features of EV71 and host responses resulting from EV71 infection. Six different EV71 strains were isolated from HFMD patients with severe or mild clinical symptoms, and were analyzed for pathogenicity in vitro and in vivo. The results demonstrated that the six virus strains exhibited similar cytopathogenic effects on susceptible MA104 cells. However, marked differences in histological and immunopathological changes were observed when mice were inoculated with the different virus strains. Thus, the viruses studied were divided into two groups, highly or weakly pathogenic. Two representative virus strains, JN200804 and JN200803 (highly and weakly pathogenic, respectively) were studied further to investigate pathogenicity-associated factors, including genetic mutations and immunopathogenesis. The present study has demonstrated that highly pathogenic strains have stable genome and amino acid sequences. Notably, the present study demonstrated that a highly pathogenic strain induced a significant increase of the bulk CD4 T cell levels at 3 days post‑inoculation. In conclusion, the current study demonstrates that genomic and immunologic factors may be responsible for the multiple tissue damage caused by highly pathogenic EV71 infection. PMID:27035332

  2. Vulnerability to chronic subordination stress-induced depression-like disorders in adult 129SvEv male mice.

    PubMed

    Dadomo, Harold; Sanghez, Valentina; Di Cristo, Luisana; Lori, Andrea; Ceresini, Graziano; Malinge, Isabelle; Parmigiani, Stefano; Palanza, Paola; Sheardown, Malcolm; Bartolomucci, Alessandro

    2011-08-01

    Exposure to stressful life events is intimately linked with vulnerability to neuropsychiatric disorders such as major depression. Pre-clinical animal models offer an effective tool to disentangle the underlying molecular mechanisms. In particular, the 129SvEv strain is often used to develop transgenic mouse models but poorly characterized as far as behavior and neuroendocrine functions are concerned. Here we present a comprehensive characterization of 129SvEv male mice's vulnerability to social stress-induced depression-like disorders and physiological comorbidities. We employed a well characterized mouse model of chronic social stress based on social defeat and subordination. Subordinate 129SvEv mice showed body weight gain, hyperphagia, increased adipose fat pads weight and basal plasma corticosterone. Home cage phenotyping revealed a suppression of spontaneous locomotor activity and transient hyperthermia. Subordinate 129SvEv mice also showed marked fearfulness, anhedonic-like response toward a novel but palatable food, increased anxiety in the elevated plus maze and social avoidance of an unfamiliar male mouse. A direct measured effect of the stressfulness of the living environment, i.e. the amount of daily aggression received, predicted the degree of corticosterone level and locomotor activity but not of the other parameters. This is the first study validating a chronic subordination stress paradigm in 129SvEv male mice. Results demonstrated remarkable stress vulnerability and establish the validity to use this mouse strain as a model for depression-like disorders. PMID:21093519

  3. High-quantum-efficiency 0.5 eV GaInAsSb/GaSb thermophotovoltaic devices

    SciTech Connect

    Wang, C.A.; Choi, H.K.; Ransom, S.L.; Charache, G.W.; Danielson, L.R.; DePoy, D.M.

    1999-08-01

    We report high-performance lattice-matched GaInAsSb/GaSb thermophotovoltaic (TPV) devices with a 0.5 eV band gap. The TPV structures were grown on GaSb substrates by organometallic vapor phase epitaxy at a lower temperature (525 {degree}C compared to 550 {degree}C) to improve the quality of the metastable GaInAsSb alloy. The 0.5 eV TPV devices exhibit external quantum efficiency as high as 60{percent}, which corresponds to an internal quantum efficiency of 90{percent}, assuming 35{percent} reflection losses. This efficiency is comparable to the value measured for 0.53 eV devices. The ratio of the open circuit voltage to band-gap energy ratio decreases from 0.57 for 0.53 eV devices to 0.48 for 0.5 eV devices. {copyright} {ital 1999 American Institute of Physics.}

  4. Genomic and immunologic factors associated with viral pathogenesis in a lethal EV71 infected neonatal mouse model

    PubMed Central

    YUE, YINGYING; LI, PENG; SONG, NANNAN; LI, BINGQING; LI, ZHIHUI; GUO, YUQI; ZHANG, WEIDONG; WEI, MING Q.; GAI, ZHONGTAO; MENG, HONG; WANG, JIWEN; QIN, LIZENG

    2016-01-01

    Hand, foot and mouth disease (HFMD) caused by enterovirus 71 (EV71) has emerged as a major health problem in China and worldwide. The present study aimed to understand the virological features of EV71 and host responses resulting from EV71 infection. Six different EV71 strains were isolated from HFMD patients with severe or mild clinical symptoms, and were analyzed for pathogenicity in vitro and in vivo. The results demonstrated that the six virus strains exhibited similar cytopathogenic effects on susceptible MA104 cells. However, marked differences in histological and immunopathological changes were observed when mice were inoculated with the different virus strains. Thus, the viruses studied were divided into two groups, highly or weakly pathogenic. Two representative virus strains, JN200804 and JN200803 (highly and weakly pathogenic, respectively) were studied further to investigate pathogenicity-associated factors, including genetic mutations and immunopathogenesis. The present study has demonstrated that highly pathogenic strains have stable genome and amino acid sequences. Notably, the present study demonstrated that a highly pathogenic strain induced a significant increase of the bulk CD4 T cell levels at 3 days post-inoculation. In conclusion, the current study demonstrates that genomic and immunologic factors may be responsible for the multiple tissue damage caused by highly pathogenic EV71 infection. PMID:27035332

  5. Comparing the Primary and Recall Immune Response Induced by a New EV71 Vaccine Using Systems Biology Approaches

    PubMed Central

    Wu, Xing; Mao, Qunying; Chen, Pan; Zhu, Fengcai; Xu, Miao; Kong, Wei; Liang, Zhenglun; Wang, Junzhi

    2015-01-01

    Three inactivated EV71 whole-virus vaccines have completed Phase III clinical trials in mainland China, with high efficacy, satisfactory safety, and sustained immunogenicity. However, the molecular mechanisms how this new vaccine elicit potent immune response remain poorly understood. To characterize the primary and recall responses to EV71 vaccines, PBMC from 19 recipients before and after vaccination with EV71 vaccine are collected and their gene expression signatures after stimulation with EV71 antigen were compared. The results showed that primary and recall response to EV71 antigen have both activated an IRF7 regulating type I interferon and antiviral immune response network. However, up-regulated genes involved in T cell activation regulated by IRF1, inflammatory response, B-cell activation and humoral immune response were only observed in recall response. The specific secretion of IL-10 in primary response and IL-2,IP-10,CCL14a, CCL21 in recall response was consistent with the activation of immune response process found in genes. Furthermore, the expression of MX1 and secretion of IP-10 in recall response were strongly correlated with NTAb level at 180d after vaccination (r = 0.81 and 0.99). In summary, inflammatory response, adaptive immune response and a stronger antiviral response were indentified in recall response. PMID:26465882

  6. State-Selective Differential Cross Section Measurements for the One-Electron Capture Process in C3+-He and C3+-Ne Systems at Elab = 33 eV

    NASA Astrophysics Data System (ADS)

    Itoh, Yoh

    2015-06-01

    Using a crossed-beam apparatus, we measured the relative state-selective differential cross sections (DCSs) for the following reactions: C3+ (1s2 2s 2S) + He (1s2 1S) → C2+ (1s2 2s2p 1P) + He+ (1s 2S) + 10.6 eV and C3+ (1s2 2s 2S) + Ne (2p6 1S) → C2+ (1s2 2p2 1D) + Ne+ (2p5 2P) + 8.2 eV. The scattering angle studied in the laboratory frame, θlab, was from -3.0 to 24°, and the laboratory collision energy Elab was 33 eV. In both systems, the DCSs for the reaction are zero at the center-of-mass angle θcm = 0, and show a peak at a certain angle and a broad hump at larger angles. A classical trajectory analysis within the two-state approximation based on the ab initio potentials for (CHe)3+ revealed that these structures observed are ascribed to the reactions that occur in different trajectories. The peak corresponds to the reactions occurring in the outgoing part of the trajectory, and the hump is associated with the reactions occurring mainly in the incoming part of the trajectory.

  7. Two-photon double ionization of helium in the region of photon energies 42-50 eV

    SciTech Connect

    Ivanov, I. A.; Kheifets, A. S.

    2007-03-15

    We report the total integrated cross section (TICS) of two-photon double ionization of helium in the photon energy range from 42 to 50 eV. Our computational procedure relies on a numerical solution of the time-dependent Schroedinger equation on a square-integrable basis and subsequent projection of this solution on a set of final field-free states describing correlation in the two-electron continuum. Our results suggest that the TICS grows monotonically as a function of photon energy in the region of 42-50 eV, possibly reaching a maximum in the vicinity of 50 eV. We also present fully resolved triple-differential cross sections for selected photon energies.

  8. Scanning tunneling microscope observation of plasmid DNA under electron irradiation at 8-40 eV

    SciTech Connect

    Mochiji, K.; Hashimoto, H.; Tanaka, Y.; Ninomiya, N.; Takeo, M.

    2007-03-01

    The structural changes in plasmid DNA adsorbed onto graphite following low-energy electron irradiation were investigated. Using a scanning tunneling microscope (STM), we observed networks or islands of DNA consisting of entangled molecules and compared the shapes of the DNA before and after electron irradiation at 8-40 eV field emitted from the tip of the STM. The shape of the DNA changed depending on the electron energy. Electrons with very low energy, such as 8 or 13 eV, extended the area of a DNA island, while the electrons at 18 or 38 eV degraded it. Both types of changes tend to saturate as the electron dose increases. We also discuss the above results in terms of the chemical reactions, such as strand breaks or molecular dissociation, induced by low-energy electrons.

  9. Absolute vibrational cross sections for 1-19 eV electron scattering from condensed tetrahydrofuran (THF)

    NASA Astrophysics Data System (ADS)

    Lemelin, V.; Bass, A. D.; Cloutier, P.; Sanche, L.

    2016-02-01

    Absolute cross sections (CSs) for vibrational excitation by 1-19 eV electrons impacting on condensed tetrahydrofuran (THF) were measured with a high-resolution electron energy loss spectrometer. Experiments were performed under ultra-high vacuum (3 × 10-11 Torr) at a temperature of about 20 K. The magnitudes of the vibrational CSs lie within the 10-17 cm2 range. Features observed near 4.5, 9.5, and 12.5 eV in the incident energy dependence of the CSs were compared to the results of theoretical calculations and other experiments on gas and solid-phase THF. These three resonances are attributed to the formation of shape or core-excited shape resonances. Another maximum observed around 2.5 eV is not found in the calculations but has been observed in gas-phase studies; it is attributed to the formation of a shape resonance.

  10. Observation of the suppression of the flux of cosmic rays above 4 x 10 (19) eV.

    PubMed

    Abraham, J; Abreu, P; Aglietta, M; Aguirre, C; Allard, D; Allekotte, I; Allen, J; Allison, P; Alvarez-Muñiz, J; Ambrosio, M; Anchordoqui, L; Andringa, S; Anzalone, A; Aramo, C; Argirò, S; Arisaka, K; Armengaud, E; Arneodo, F; Arqueros, F; Asch, T; Asorey, H; Assis, P; Atulugama, B S; Aublin, J; Ave, M; Avila, G; Bäcker, T; Badagnani, D; Barbosa, A F; Barnhill, D; Barroso, S L C; Baughman, B; Bauleo, P; Beatty, J J; Beau, T; Becker, B R; Becker, K H; Bellido, J A; Benzvi, S; Berat, C; Bergmann, T; Bernardini, P; Bertou, X; Biermann, P L; Billoir, P; Blanch-Bigas, O; Blanco, F; Blasi, P; Bleve, C; Blümer, H; Bohácová, M; Bonifazi, C; Bonino, R; Brack, J; Brogueira, P; Brown, W C; Buchholz, P; Bueno, A; Burton, R E; Busca, N G; Caballero-Mora, K S; Cai, B; Camin, D V; Caramete, L; Caruso, R; Carvalho, W; Castellina, A; Catalano, O; Cataldi, G; Cazon, L; Cester, R; Chauvin, J; Chiavassa, A; Chinellato, J A; Chou, A; Chudoba, J; Chye, J; Clark, P D J; Clay, R W; Colombo, E; Conceição, R; Connolly, B; Contreras, F; Coppens, J; Cordier, A; Cotti, U; Coutu, S; Covault, C E; Creusot, A; Criss, A; Cronin, J; Curutiu, A; Dagoret-Campagne, S; Daumiller, K; Dawson, B R; de Almeida, R M; De Donato, C; de Jong, S J; De La Vega, G; Junior, W J M de Mello; Neto, J R T de Mello; De Mitri, I; de Souza, V; Del Peral, L; Deligny, O; Della Selva, A; Fratte, C Delle; Dembinski, H; Di Giulio, C; Diaz, J C; Diep, P N; Dobrigkeit, C; D'Olivo, J C; Dong, P N; Dornic, D; Dorofeev, A; Dos Anjos, J C; Dova, M T; D'Urso, D; Dutan, I; Duvernois, M A; Engel, R; Epele, L; Erdmann, M; Escobar, C O; Etchegoyen, A; Luis, P Facal San; Falcke, H; Farrar, G; Fauth, A C; Fazzini, N; Ferrer, F; Ferrero, A; Fick, B; Filevich, A; Filipcic, A; Fleck, I; Fracchiolla, C E; Fulgione, W; García, B; Gámez, D García; Garcia-Pinto, D; Garrido, X; Geenen, H; Gelmini, G; Gemmeke, H; Ghia, P L; Giller, M; Glass, H; Gold, M S; Golup, G; Albarracin, F Gomez; Berisso, M Gómez; Gonçalves, P; do Amaral, M Gonçalves; Gonzalez, D; Gonzalez, J G; González, M; Góra, D; Gorgi, A; Gouffon, P; Grassi, V; Grillo, A F; Grunfeld, C; Guardincerri, Y; Guarino, F; Guedes, G P; Gutiérrez, J; Hague, J D; Halenka, V; Hamilton, J C; Hansen, P; Harari, D; Harmsma, S; Harton, J L; Haungs, A; Hauschildt, T; Healy, M D; Hebbeker, T; Hebrero, G; Heck, D; Hojvat, C; Holmes, V C; Homola, P; Hörandel, J R; Horneffer, A; Hrabovský, M; Huege, T; Hussain, M; Iarlori, M; Insolia, A; Ionita, F; Italiano, A; Kaducak, M; Kampert, K H; Karova, T; Kasper, P; Kégl, B; Keilhauer, B; Kemp, E; Kieckhafer, R M; Klages, H O; Kleifges, M; Kleinfeller, J; Knapik, R; Knapp, J; Koang, D-H; Krieger, A; Krömer, O; Kuempel, D; Kunka, N; Kusenko, A; La Rosa, G; Lachaud, C; Lago, B L; Lebrun, D; Lebrun, P; Lee, J; de Oliveira, M A Leigui; Letessier-Selvon, A; Leuthold, M; Lhenry-Yvon, I; López, R; Agüera, A Lopez; Bahilo, J Lozano; Lucero, A; García, R Luna; Maccarone, M C; Macolino, C; Maldera, S; Mancarella, G; Manceñido, M E; Mandat, D; Mantsch, P; Mariazzi, A G; Maris, I C; Falcon, H R Marquez; Martello, D; Martínez, J; Bravo, O Martínez; Mathes, H J; Matthews, J; Matthews, J A J; Matthiae, G; Maurizio, D; Mazur, P O; McCauley, T; McEwen, M; McNeil, R R; Medina, M C; Medina-Tanco, G; Melo, D; Menichetti, E; Menschikov, A; Meurer, C; Meyhandan, R; Micheletti, M I; Miele, G; Miller, W; Mollerach, S; Monasor, M; Ragaigne, D Monnier; Montanet, F; Morales, B; Morello, C; Moreno, J C; Morris, C; Mostafá, M; Muller, M A; Mussa, R; Navarra, G; Navarro, J L; Navas, S; Necesal, P; Nellen, L; Newman-Holmes, C; Newton, D; Nhung, P T; Nierstenhoefer, N; Nitz, D; Nosek, D; Nozka, L; Oehlschläger, J; Ohnuki, T; Olinto, A; Olmos-Gilbaja, V M; Ortiz, M; Ortolani, F; Ostapchenko, S; Otero, L; Pacheco, N; Selmi-Dei, D Pakk; Palatka, M; Pallotta, J; Parente, G; Parizot, E; Parlati, S; Pastor, S; Patel, M; Paul, T; Pavlidou, V; Payet, K; Pech, M; Pekala, J; Pelayo, R; Pepe, I M; Perrone, L; Pesce, R; Petrera, S; Petrinca, P; Petrov, Y; Pichel, A; Piegaia, R; Pierog, T; Pimenta, M; Pinto, T; Pirronello, V; Pisanti, O; Platino, M; Pochon, J; Privitera, P; Prouza, M; Quel, E J; Rautenberg, J; Redondo, A; Reucroft, S; Revenu, B; Rezende, F A S; Ridky, J; Riggi, S; Risse, M; Rivière, C; Rizi, V; Roberts, M; Robledo, C; Rodriguez, G; Martino, J Rodriguez; Rojo, J Rodriguez; Rodriguez-Cabo, I; Rodríguez-Frías, M D; Ros, G; Rosado, J; Roth, M; Rouillé-d'Orfeuil, B; Roulet, E; Rovero, A C; Salamida, F; Salazar, H; Salina, G; Sánchez, F; Santander, M; Santo, C E; Santos, E M; Sarazin, F; Sarkar, S; Sato, R; Scherini, V; Schieler, H; Schmidt, A; Schmidt, F; Schmidt, T; Scholten, O; Schovánek, P; Schroeder, F; Schulte, S; Schüssler, F; Sciutto, S J; Scuderi, M; Segreto, A; Semikoz, D; Settimo, M; Shellard, R C; Sidelnik, I; Siffert, B B; Sigl, G

    2008-08-01

    The energy spectrum of cosmic rays above 2.5 x 10;{18} eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index gamma of the particle flux, J proportional, variantE;{-gamma}, at energies between 4 x 10;{18} eV and 4 x 10;{19} eV is 2.69+/-0.02(stat)+/-0.06(syst), steepening to 4.2+/-0.4(stat)+/-0.06(syst) at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuz'min. PMID:18764444

  11. Observation of the suppression of the flux of cosmic rays above 4x10^19eV

    SciTech Connect

    Abraham, J.; Abreu, P.; Aglietta, M.; Aguirre, C.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Alvarez-Muniz, J.; Ambrosio, M.; Anchordoqui, L.; /Wisconsin U., Milwaukee /Northeastern U. /Lisbon, IST /Lisbon, LIFEP

    2008-06-01

    The energy spectrum of cosmic rays above 2.5 x 10{sup 18} eV, derived from 20,000 events recorded at the Pierre Auger Observatory, is described. The spectral index {gamma} of the particle flux, J {proportional_to} E{sup {gamma}}, at energies between 4 x 10{sup 18} eV and 4 x 10{sup 19} eV is 2.69 {+-} 0.02(stat){+-}0.06(syst), steepening to 4.2 {+-} 0.4(stat){+-}0.06(syst) at higher energies. The hypothesis of a single power law is rejected with a significance greater than 6 standard deviations. The data are consistent with the prediction by Greisen and by Zatsepin and Kuzmin.

  12. Two-photon double ionization of helium in the region of photon energies 42-50eV

    NASA Astrophysics Data System (ADS)

    Ivanov, I. A.; Kheifets, A. S.

    2007-03-01

    We report the total integrated cross section (TICS) of two-photon double ionization of helium in the photon energy range from 42to50eV . Our computational procedure relies on a numerical solution of the time-dependent Schrödinger equation on a square-integrable basis and subsequent projection of this solution on a set of final field-free states describing correlation in the two-electron continuum. Our results suggest that the TICS grows monotonically as a function of photon energy in the region of 42-50eV , possibly reaching a maximum in the vicinity of 50eV . We also present fully resolved triple-differential cross sections for selected photon energies.

  13. MASS SPECTROMETRY

    DOEpatents

    Nier, A.O.C.

    1959-08-25

    A voltage switching apparatus is described for use with a mass spectrometer in the concentratron analysis of several components of a gas mixture. The system automatically varies the voltage on the accelerating electrode of the mass spectrometer through a program of voltages which corresponds to the particular gas components under analysis. Automatic operation may be discontinued at any time to permit the operator to manually select any desired predetermined accelerating voltage. Further, the system may be manually adjusted to vary the accelerating voltage over a wide range.

  14. Performance of reversed transcription loop-mediated isothermal amplification technique detecting EV71: a systematic review with meta-analysis.

    PubMed

    Lei, Xiaoying; Wen, Hongling; Zhao, Li; Yu, Xuejie

    2014-04-01

    Human enterovirus 71 (EV71) is the major etiological agent of hand, foot and mouth disease (HFMD), which is a common infectious disease in young children. Studies in the past have shown that reversed transcription loop-mediated isothermal amplification (RT-LAMP) was a rapid approach for the detection of EV71 in HFMD. This meta-analysis study is to evaluate the diagnostic role of RT-LAMP in detecting EV71 infection. A comprehensive literature research of PubMed, Embase, Wan Fang Data, and Chinese National Knowledge Infrastructure databases was conducted on articles aiming at the diagnostic performance of RT-LAMP in EV71 detection published before February 10, 2014. Data from selected studies were pooled to yield the summary sensitivity, specificity, positive and negative likelihood ratio (PLR, NLR), diagnostic odds ratio (DOR), and receiver operating characteristic (SROC) curve by using STATA VERSION 12.0 software. Ten studies including a total of 907 clinical samples were of high quality in this meta-analysis. Overall, the pooled sensitivity, specificity, PLR, NLR, DOR, and the area under the SROC curve was 0.99 (0.97, 1.00), 0.97 (0.94, 1.00), 5.90 (95% CI: 3.90-8.94), 0.20 (95% CI: 0.14-0.29), and 1.00 (95% CI: 0.99-1.00), respectively. The univariate analysis of potential variables showed some changes in the diagnostic performance, but none of the differences reached statistical significance. Despite inter-study variability, the test performance of RT-LAMP was consistent with real-time RT-PCR in detecting EV71. This meta-analysis suggests that RT-LAMP is a useful diagnostic tool with high sensitivity and specificity for detecting EV71. PMID:24815384

  15. Similar protective immunity induced by an inactivated enterovirus 71 (EV71) vaccine in neonatal rhesus macaques and children.

    PubMed

    Zhang, Ying; Wang, Lichun; Liao, Yun; Liu, Longding; Ma, Kaili; Yang, Erxia; Wang, Jingjing; Che, Yanchun; Jiang, Li; Pu, Jing; Guo, Lei; Feng, Min; Liang, Yan; Cui, Wei; Yang, Huai; Li, Qihan

    2015-11-17

    During the development of enterovirus 71 (EV71) inactivated vaccine for preventing human hand, foot and mouth diseases (HFMD) by EV71 infection, an effective animal model is presumed to be significant and necessary. Our previous study demonstrated that the vesicles in oral regions and limbs potentially associated with viremia, which are the typical manifestations of HFMD, and remarkable pathologic changes were identified in various tissues of neonatal rhesus macaque during EV71 infection. Although an immune response in terms of neutralizing antibody and T cell memory was observed in animals infected by the virus or stimulated by viral antigen, whether such a response could be considered as an indicator to justify the immune response in individuals vaccinated or infected in a pandemic needs to be investigated. Here, a comparative analysis of the neutralizing antibody response and IFN-γ-specific T cell response in vaccinated neonatal rhesus macaques and a human clinical trial with an EV71 inactivated vaccine was performed, and the results showed the identical tendency and increased level of neutralizing antibody and the IFN-γ-specific T cell response stimulated by the EV71 antigen peptide. Importantly, the clinical protective efficacy against virus infection by the elicited immune response in the immunized population compared with the placebo control and the up-modulated gene profile associated with immune activation were similar to those in infected macaques. Further safety verification of this vaccine in neonatal rhesus macaques and children confirmed the potential use of the macaque as a reliable model for the evaluation of an EV71 candidate vaccine. PMID:26419198

  16. A First Look at the Impact of Electric Vehicle Charging on the Electric Grid in the EV Project

    SciTech Connect

    Stephen L. Schey; John G. Smart; Don R. Scoffield

    2012-05-01

    ECOtality was awarded a grant from the U.S. Department of Energy to lead a large-scale electric vehicle charging infrastructure demonstration, called The EV Project. ECOtality has partnered with Nissan North America, General Motors, the Idaho National Laboratory, and others to deploy and collect data from over 5,000 Nissan LEAFsTM and Chevrolet Volts and over 10,000 charging systems in 18 regions across the United States. This paper summarizes usage of residential charging units in The EV Project, based on data collected through the end of 2011. This information is provided to help analysts assess the impact on the electric grid of early adopter charging of grid-connected electric drive vehicles. A method of data aggregation was developed to summarize charging unit usage by the means of two metrics: charging availability and charging demand. Charging availability is plotted to show the percentage of charging units connected to a vehicle over time. Charging demand is plotted to show charging demand on the electric gird over time. Charging availability for residential charging units is similar in each EV Project region. It is low during the day, steadily increases in evening, and remains high at night. Charging demand, however, varies by region. Two EV Project regions were examined to identify regional differences. In Nashville, where EV Project participants do not have time-of-use electricity rates, demand increases each evening as charging availability increases, starting at about 16:00. Demand peaks in the 20:00 hour on weekdays. In San Francisco, where the majority of EV Project participants have the option of choosing a time-of-use rate plan from their electric utility, demand spikes at 00:00. This coincides with the beginning of the off-peak electricity rate period. Demand peaks at 01:00.

  17. PHEV-EV Charger Technology Assessment with an Emphasis on V2G Operation

    SciTech Connect

    Kisacikoglu, Mithat C; Bedir, Abdulkadir; Ozpineci, Burak; Tolbert, Leon M

    2012-03-01

    More battery powered electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) will be introduced to the market in 2011 and beyond. Since these vehicles have large batteries that need to be charged from an external power source or directly from the grid, their batteries, charging circuits, charging stations/infrastructures, and grid interconnection issues are garnering more attention. This report summarizes information regarding the batteries used in PHEVs, different types of chargers, charging standards and circuits, and compares different topologies. Furthermore, it includes a list of vehicles that are going to be in the market soon with information on their charging and energy storage equipment. A summary of different standards governing charging circuits and charging stations concludes the report. There are several battery types that are available for PHEVs; however, the most popular ones have nickel metal hydride (NiMH) and lithium-ion (Li-ion) chemistries. The former one is being used in current hybrid electric vehicles (HEVs), but the latter will be used in most of the PHEVs and EVs due to higher energy densities and higher efficiencies. The chargers can be classified based on the circuit topologies (dedicated or integrated), location of the charger (either on or off the vehicle), connection (conductive, inductive/wireless, and mechanical), electrical waveform (direct current (dc) or alternating current (ac)), and the direction of power flow (unidirectional or bidirectional). The first PHEVs typically will have dedicated, on-board, unidirectional chargers that will have conductive connections to the charging stations or wall outlets and will be charged using either dc or ac. In the near future, bidirectional chargers might also be used in these vehicles once the benefits of practical vehicle to grid applications are realized. The terms charger and charging station cause terminology confusion. To prevent misunderstandings, a more descriptive term

  18. Chromatography and its hyphenation to mass spectrometry for extracellular vesicle analysis.

    PubMed

    Pocsfalvi, Gabriella; Stanly, Christopher; Fiume, Immacolata; Vékey, Károly

    2016-03-25

    Extracellular vesicles (EVs), such as exosomes, microvesicles and apoptotic bodies are released by cells, both under physiological and pathological conditions. EVs can participate in a novel type of intercellular communication and deliver cargo of nucleic acids, proteins and lipids near or to distant host cells. EV research is proceeding at a fast pace; now they start to appear as promising therapeutic targets, diagnostic tools and drug delivery systems. Isolation and analysis of EVs are prerequisites for understanding their biological roles and for their clinical exploitation. In this process chromatography and mass spectrometry (MS)-based strategies are rapidly gaining importance; and are reviewed in the present communication. Isolation and purification of EVs is mostly performed by ultracentrifugation at present. Chromatography-based strategies are gaining ground, among which affinity and size exclusion chromatography (SEC) are particularly strong contenders. Their major advantages are the relative simplicity, robustness and throughput. Affinity chromatography has the added advantage of separating EV subtypes based on molecular recognition of EV surface motifs. SEC has the advantage that isolated EVs may retain their biological activity. EVs are typically isolated in small amounts, therefore high sensitivity is required for their analysis. Study of the molecular content of EVs (all compounds beside nucleic acids) is predominantly based on liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis. The chromatographic separation is mostly performed by reverse phase, nanoscale, ultra high performance LC technique. The MS analysis relying typically on nano-electrospray ionization MS/MS provides high sensitivity, selectivity and resolution, so that thousand(s) of proteins can be detected/identified/quantified in a EV sample. Beside protein identification, quantitation and characterization of protein post-translational modifications (PTMs), like glycosylation

  19. DNA strand breaks and crosslinks induced by transient anions in the range 2-20 eV

    SciTech Connect

    Luo, Xinglan; Zheng, Yi; Sanche, Léon

    2014-04-21

    The energy dependence of the yields of single and double strand breaks (SSB and DSB) and crosslinks induced by electron impact on plasmid DNA films is measured in the 2-20 eV range. The yield functions exhibit two strong maxima, which are interpreted to result from the formation of core-excited resonances (i.e., transient anions) of the bases, and their decay into the autoionization channel, resulting in π → π{sup *} electronic transitions of the bases followed by electron transfer to the C–O σ{sup *} bond in the phosphate group. Occupancy of the σ{sup *} orbital ruptures the C–O bond of the backbone via dissociative electron attachment, producing a SSB. From a comparison of our results with those of other works, including theoretical calculations and electron-energy-loss spectra of the bases, the 4.6 eV peak in the SSB yield function is attributed to the resonance decay into the lowest electronically excited states of the bases; in particular, those resulting from the transitions 1{sup 3}A{sup ′} (π{sub 2} → π{sub 3}{sup *}) and 1{sup 3}A{sup ″} (n{sub 2} → π{sub 3}{sup *}) of thymine and 1{sup 3}A{sup ′} (π → π{sup *}) of cytosine. The strongest peak at 9.6 eV in the SSB yield function is also associated with electron captured by excited states of the bases, resulting mostly from a multitude of higher-energy π → π{sup *} transitions. The DSB yield function exhibits strong maxima at 6.1 and 9.6 eV. The peak at 9.6 eV is probably related to the same resonance manifold as that leading to SSB, but the other at 6.1 eV may be more restricted to decay into the electronic state 1{sup 3}A{sup ′} (π → π{sup *}) of cytosine via autoionization. The yield function of crosslinks is dominated by a broad peak extending over the 3.6-11.6 eV range with a sharper one at 17.6 eV. The different line shape of the latter function, compared to that of SSB and DSB, appears to be due to the formation of reactive radical sites in the initial supercoiled

  20. Monte Carlo simulation of EAS generated by 10(14) - 10(16) eV protons

    NASA Technical Reports Server (NTRS)

    Fenyves, E. J.; Yunn, B. C.; Stanev, T.

    1985-01-01

    Detailed Monte Carlo simulations of extensive air showers to be detected by the Homestake Surface Underground Telescope and other similar detectors located at sea level and mountain altitudes have been performed for 10 to the 14th power to 10 to the 16th power eV primary energies. The results of these Monte Carlo calculations will provide an opportunity to compare the experimental data with different models for the composition and spectra of primaries and for the development of air showers. The results obtained for extensive air showers generated by 10 to the 14th power to 10 to the 16th power eV primary protons are reported.

  1. Skid Prevention for EVs Based on the Emulation of Torque Reduction Characteristics of Separately-excited DC Motor

    NASA Astrophysics Data System (ADS)

    Kodama, Shinya; Hori, Yoichi

    It is well-known that the separately-excited DC motor has effective torque (current) reduction characteristics in response to rapid increase in the rotational speed of the motor. These characteristics have been utilized in adhesion control of electric railway trains with separately-excited DC motor. Up to now, we have proposed a new skid prevention method for EVs, utilizing these characteristics and have made experiments with the hardware skid simulator “Motor-Generator setup”. In this paper, we applied this skid prevention control to our new vehicle “UOT CADWELL EV" equipped with BLDC motors and showed its effectiveness.

  2. DNA strand breaks and crosslinks induced by transient anions in the range 2-20 eV

    NASA Astrophysics Data System (ADS)

    Luo, Xinglan; Zheng, Yi; Sanche, Léon

    2014-04-01

    The energy dependence of the yields of single and double strand breaks (SSB and DSB) and crosslinks induced by electron impact on plasmid DNA films is measured in the 2-20 eV range. The yield functions exhibit two strong maxima, which are interpreted to result from the formation of core-excited resonances (i.e., transient anions) of the bases, and their decay into the autoionization channel, resulting in π → π* electronic transitions of the bases followed by electron transfer to the C-O σ* bond in the phosphate group. Occupancy of the σ* orbital ruptures the C-O bond of the backbone via dissociative electron attachment, producing a SSB. From a comparison of our results with those of other works, including theoretical calculations and electron-energy-loss spectra of the bases, the 4.6 eV peak in the SSB yield function is attributed to the resonance decay into the lowest electronically excited states of the bases; in particular, those resulting from the transitions 13A' (π2 → π3*) and 13A″ (n2 → π3*) of thymine and 13A' (π → π*) of cytosine. The strongest peak at 9.6 eV in the SSB yield function is also associated with electron captured by excited states of the bases, resulting mostly from a multitude of higher-energy π → π* transitions. The DSB yield function exhibits strong maxima at 6.1 and 9.6 eV. The peak at 9.6 eV is probably related to the same resonance manifold as that leading to SSB, but the other at 6.1 eV may be more restricted to decay into the electronic state 13A' (π → π*) of cytosine via autoionization. The yield function of crosslinks is dominated by a broad peak extending over the 3.6-11.6 eV range with a sharper one at 17.6 eV. The different line shape of the latter function, compared to that of SSB and DSB, appears to be due to the formation of reactive radical sites in the initial supercoiled configuration of the plasmid, which react with the circular form (i.e., DNA with a SSB) to produce a crosslink.

  3. Scrotal masses

    MedlinePlus

    ... your provider to determine if it may be testicular cancer. Prevention You can prevent scrotal masses caused by sexually ... 21095426 . U.S. Preventive Services Task Force. Screening for Testicular Cancer: U.S. Preventive Services Task Force reaffirmation recommendation statement. Ann Intern ...

  4. Neutrino mass and dark energy from weak lensing.

    PubMed

    Abazajian, Kevork N; Dodelson, Scott

    2003-07-25

    Weak gravitational lensing of background galaxies by intervening matter directly probes the mass distribution in the Universe. This distribution is sensitive to both the dark energy and neutrino mass. We examine the potential of lensing experiments to measure features of both simultaneously. Focusing on the radial information contained in a future deep 4000 deg(2) survey, we find that the expected (1-sigma) error on a neutrino mass is 0.1 eV, if the dark-energy parameters are allowed to vary. The constraints on dark-energy parameters are similarly restrictive, with errors on w of 0.09. PMID:12906650

  5. Plasma mass filtering for separation of actinides from lanthanides

    NASA Astrophysics Data System (ADS)

    Gueroult, R.; Fisch, N. J.

    2014-06-01

    Separating lanthanides from actinides is a key process in reprocessing nuclear spent fuel. Plasma mass filters, which operate on dissociated elements, offer conceptual advantages for such a task as compared with conventional chemical methods. The capabilities of a specific plasma mass filter concept, called the magnetic centrifugal mass filter, are analyzed within this particular context. Numerical simulations indicate separation of americium ions from a mixture of lanthanides ions for plasma densities of the order of 1012 cm-3, and ion temperatures of about 10 eV. In light of collision considerations, separating small fractions of heavy elements from a larger volume of lighter ones is shown to enhance the separation capabilities.

  6. Atmospheric-pressure Penning ionization mass spectrometry.

    PubMed

    Hiraoka, Kenzo; Fujimaki, Susumu; Kambara, Shizuka; Furuya, Hiroko; Okazaki, Shigemitsu

    2004-01-01

    A preliminary study on the atmospheric-pressure Penning ionization (APP(e)I) of gaseous organic compounds with Ar* has been made. The metastable argon atoms (Ar*: 11.55 eV for (3)P(2) and 11.72 eV for (3)P(0)) were generated by the negative-mode corona discharge of atmospheric-pressure argon gas. By applying a high positive voltage (+500 to +1000 V) to the stainless steel capillary for the sample introduction (0.1 mm i.d., 0.3 mm o.d.), strong ion signals could be obtained. The ions formed were sampled through an orifice into the vacuum and mass-analyzed by an orthogonal time-of-flight mass spectrometer. The major ions formed by APP(e)I are found to be molecular-related ions for alkanes, aromatics, and oxygen-containing compounds. Because only the molecules with ionization energies less than the internal energy of Ar* are ionized, the present method will be a selective and highly sensitive interface for gas chromatography/mass spectrometry. PMID:15384154

  7. Collisional-radiative modeling of tungsten at temperatures of 1200–2400 eV

    SciTech Connect

    Colgan, James; Fontes, Christopher; Zhang, Honglin; Abdallah, Jr., Joseph

    2015-04-30

    We discuss new collisional-radiative modeling calculations of tungsten at moderate temperatures of 1200 to 2400 eV. Such plasma conditions are relevant to ongoing experimental work at ASDEX Upgrade and are expected to be relevant for ITER. Our calculations are made using the Los Alamos National Laboratory (LANL) collisional-radiative modeling ATOMIC code. These calculations formed part of a submission to the recent NLTE-8 workshop that was held in November 2013. This series of workshops provides a forum for detailed comparison of plasma and spectral quantities from NLTE collisional-radiative modeling codes. We focus on the LANL ATOMIC calculations for tungsten that were submitted to the NLTE-8 workshop and discuss different models that were constructed to predict the tungsten emission. In particular, we discuss comparisons between semi-relativistic configuration-average and fully relativistic configuration-average calculations. We also present semi-relativistic calculations that include fine-structure detail, and discuss the difficult problem of ensuring completeness with respect to the number of configurations included in a CR calculation.

  8. Testing and evaluation of EV-1300 lead-acid modules for the hybrid vehicle application

    SciTech Connect

    Gay, E.C.; Corp, D.O.; Hayes, E.R.; Webster, C.E.; Hornstra, F.; Yao, N.P.

    1984-01-01

    Tests of two 6-cell, EV-1300 modules with a capacity of 105 Ah (1235 Wh) were conducted at the computer-automated National Battery Test Laboratory at Argonne National Laboratory to verify the above design requirements. In addition, the following tests were completed to more fully characterize the performance of the battery: (1) capacity measurements over a range of constant-current discharges of 35 to 400 A (Peukert Plot); (2) energy measurements over a range of constant-power discharges of 10 to 100 W/kg (Ragone Plot); (3) open-circuit stand testing (self-discharge); (4) partial DOD testing (memory effect); (5) projected range based on simulated driving profile discharges representing the EPA urban driving schedule negotiated by the HTV-1 hybrid vehicle with minimum ICE operation; (6) projected range based on simulated driving profile discharges representing the SAE J227aD urban driving schedule negotiated by an improved ETV-1 (an all-electric vehicle); and (7) peak power measurements at various depths of discharge.

  9. Invited Article: High resolution angle resolved photoemission with tabletop 11 eV laser.

    PubMed

    He, Yu; Vishik, Inna M; Yi, Ming; Yang, Shuolong; Liu, Zhongkai; Lee, James J; Chen, Sudi; Rebec, Slavko N; Leuenberger, Dominik; Zong, Alfred; Jefferson, C Michael; Moore, Robert G; Kirchmann, Patrick S; Merriam, Andrew J; Shen, Zhi-Xun

    2016-01-01

    We developed a table-top vacuum ultraviolet (VUV) laser with 113.778 nm wavelength (10.897 eV) and demonstrated its viability as a photon source for high resolution angle-resolved photoemission spectroscopy (ARPES). This sub-nanosecond pulsed VUV laser operates at a repetition rate of 10 MHz, provides a flux of 2 × 10(12) photons/s, and enables photoemission with energy and momentum resolutions better than 2 meV and 0.012 Å(-1), respectively. Space-charge induced energy shifts and spectral broadenings can be reduced below 2 meV. The setup reaches electron momenta up to 1.2 Å(-1), granting full access to the first Brillouin zone of most materials. Control over the linear polarization, repetition rate, and photon flux of the VUV source facilitates ARPES investigations of a broad range of quantum materials, bridging the application gap between contemporary low energy laser-based ARPES and synchrotron-based ARPES. We describe the principles and operational characteristics of this source and showcase its performance for rare earth metal tritellurides, high temperature cuprate superconductors, and iron-based superconductors. PMID:26827301

  10. 0.52eV Quaternary InGaAsSb Thermophotovoltaic Diode Technology

    SciTech Connect

    MW Dashiell; JF Beausang; G Nichols; DM Depoy; LR Danielson; H Ehsani; KD Rahner; J Azarkevich; P Talamo; E Brown; S Burger; P Fourspring; W Topper; PF Baldasaro; CA Wang; R Huang; M Connors; G Turner; Z Shellenbarger; G Taylor; Jizhong Li; R Marinelli; D Donetski; S Anikeev; G Belenky; S Luryi; DR Taylor; J Hazel

    2004-06-09

    Thermophotovoltaic (TPV) diodes fabricated from 0.52eV lattice-matched InGaAsSb alloys are grown by Metal Organic Vapor Phase Epitaxy (MOVPE) on GaSb substrates. 4cm{sup 2} multi-chip diode modules with front-surface spectral filters were tested in a vacuum cavity and attained measured efficiency and power density of 19% and 0.58 W/cm{sup 2} respectively at operating at temperatures of T{sub radiator} = 950 C and T{sub diode} = 27 C. Device modeling and minority carrier lifetime measurements of double heterostructure lifetime specimens indicate that diode conversion efficiency is limited predominantly by interface recombination and photon energy loss to the GaSb substrate and back ohmic contact. Recent improvements to the diode include lattice-matched p-type AlGaAsSb passivating layers with interface recombination velocities less than 100 cm/s and new processing techniques enabling thinned substrates and back surface reflectors. Modeling predictions of these improvements to the diode architecture indicate that conversion efficiencies from 27-30% and {approx}0.85 W/cm{sup 2} could be attained under the above operating temperatures.

  11. Photodissociation of HCN and HNC isomers in the 7-10 eV energy range

    PubMed Central

    Chenel, Aurelie; Roncero, Octavio; Aguado, Alfredo; Agúndez, Marcelino; Cernicharo, José

    2016-01-01

    The ultraviolet photoabsorption spectra of the HCN and HNC isomers have been simulated in the 7-10 eV photon energy range. For this purpose the three-dimensional adiabatic potential energy surfaces of the 7 lowest electronic states, and the corresponding transition dipole moments, have been calculated, at multi reference configuration interaction level. The spectra are calculated with a quantum wave packet method on these adiabatic potential energy surfaces. The spectra for the 3 lower excited states, the dissociative electronic states, correspond essentially to predissociation peaks, most of them through tunneling on the same adiabatic state. The 3 higher electronic states are bound, hereafter electronic bound states, and their spectra consist of delta lines, in the adiabatic approximation. The radiative lifetime towards the ground electronic states of these bound states have been calculated, being longer than 10 ns in all cases, much longer that the characteristic predissociation lifetimes. The spectra of HCN is compared with the available experimental and previous theoretical simulations while in the case of HNC there are no previous studies to our knowledge. The spectrum for HNC is considerably more intense than that of HCN, which implies a much faster destruction of HNC than HCN in astrophysical environments illuminated by ultraviolet radiation. PMID:27083720

  12. Baseline Testing of the EV Global E-Bike with Ultracapacitors

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.; Kolacz, John S.; Tavernelli, Paul F.

    2001-01-01

    The NASA John H. Glenn Research Center initiated baseline testing of the EV Global E-Bike SX with ultracapacitors as a way to reduce pollution in urban areas, reduce fossil fuel consumption, and reduce operating costs for transportation systems. The E-Bike provides an inexpensive approach to advance the state of art in hybrid technology in a practical application. The project transfers space technology to terrestrial use via nontraditional partners, and provides power system data valuable for future space applications. The work was done under the Hybrid Power Management (HPM) Program, which includes the Hybrid Electric Transit Bus (HETB). The E-Bike is a state of the art, ground up, hybrid electrical bicycle. Unique features of the vehicle's power system include the use of an efficient, 400 W electric hub motor, and a seven-speed derailleur system that permits operation as fully electric, fully pedal, or a combination of the two. Other innovative features, such as regenerative braking through ultracapacitor energy storage, are planned. Regenerative braking recovers much of the kinetic energy of the vehicle during deceleration. A description of the E-bike, the results of performance testing, and future vehicle development plans are given in this report. The report concludes that the E-Bike provides excellent performance, and that the implementation of ultracapacitors in the power system can provide significant performance improvements.

  13. Rapid next-generation sequencing of dengue, EV-A71 and RSV-A viruses.

    PubMed

    Baronti, Cécile; Piorkowski, Géraldine; Leparc-Goffart, Isabelle; de Lamballerie, Xavier; Dubot-Pérès, Audrey

    2015-12-15

    Accurate characterisation of viral strains constitutes a crucial objective for the management of modern virus collections. Next-generation sequencing (NGS) provides technical solution for fast and cost-effective full genome sequencing. Here, we report protocols for rapid full-genome characterisation of RNA viruses of medical importance: dengue virus, enterovirus A71 and respiratory syncytial virus A, based on a specific amplification step followed by NGS-sequencing. A subset of full-length genome sequences representing the genetic diversity of each virus type was selected in GenBank and used to design primer sets allowing the amplification of the complete genome in 3-8 overlapping PCR fragments. The technique was used for characterising 53 strains (33 DENV, 8 EV-A71, 12 RSV-A) from various genotypes and origins. In a single assay, and in just 4 days, it provided for all strains an excellent genomic coverage (∼ 99% including complete ORF for all strains) and accurate sequences with high number of reads per position (250-3500 on average). The elaboration of specific PCR-based full-genome sequencing protocols for diverse virus groups is likely to revolutionise the characterisation of viral isolates in modern collection, but also to contribute in the next future to the study of RNA viruses directly from biological samples. PMID:26376168

  14. Linear Covariance Analysis For Proximity Operations Around Asteroid 2008 EV5

    NASA Technical Reports Server (NTRS)

    Wright, Cinnamon A.; Bhatt, Sagar; Woffinden, David; Strube, Matthew; D'Souza, Chris

    2015-01-01

    The NASA initiative to collect an asteroid, the Asteroid Robotic Redirect Mission (ARRM), is currently investigating the option of retrieving a boulder from an asteroid, demonstrating planetary defense with an enhanced gravity tractor technique, and returning it to a lunar orbit. Techniques for accomplishing this are being investigated by the Satellite Servicing Capabilities Office (SSCO) at NASA GSFC in collaboration with JPL, NASA JSC, LaRC, and Draper Laboratory, Inc. Two critical phases of the mission are the descent to the boulder and the Enhanced Gravity Tractor demonstration. A linear covariance analysis is done for these phases to assess the feasibility of these concepts with the proposed design of the sensor and actuator suite of the Asteroid Redirect Vehicle (ARV). The sensor suite for this analysis includes a wide field of view camera, LiDAR, and an IMU. The proposed asteroid of interest is currently the C-type asteroid 2008 EV5, a carbonaceous chondrite that is of high interest to the scientific community. This paper presents an overview of the linear covariance analysis techniques and simulation tool, provides sensor and actuator models, and addresses the feasibility of descending to the surface of the asteroid within allocated requirements as well as the possibility of maintaining a halo orbit to demonstrate the Enhanced Gravity Tractor technique.

  15. Invited Article: High resolution angle resolved photoemission with tabletop 11 eV laser

    NASA Astrophysics Data System (ADS)

    He, Yu; Vishik, Inna M.; Yi, Ming; Yang, Shuolong; Liu, Zhongkai; Lee, James J.; Chen, Sudi; Rebec, Slavko N.; Leuenberger, Dominik; Zong, Alfred; Jefferson, C. Michael; Moore, Robert G.; Kirchmann, Patrick S.; Merriam, Andrew J.; Shen, Zhi-Xun

    2016-01-01

    We developed a table-top vacuum ultraviolet (VUV) laser with 113.778 nm wavelength (10.897 eV) and demonstrated its viability as a photon source for high resolution angle-resolved photoemission spectroscopy (ARPES). This sub-nanosecond pulsed VUV laser operates at a repetition rate of 10 MHz, provides a flux of 2 × 1012 photons/s, and enables photoemission with energy and momentum resolutions better than 2 meV and 0.012 Å-1, respectively. Space-charge induced energy shifts and spectral broadenings can be reduced below 2 meV. The setup reaches electron momenta up to 1.2 Å-1, granting full access to the first Brillouin zone of most materials. Control over the linear polarization, repetition rate, and photon flux of the VUV source facilitates ARPES investigations of a broad range of quantum materials, bridging the application gap between contemporary low energy laser-based ARPES and synchrotron-based ARPES. We describe the principles and operational characteristics of this source and showcase its performance for rare earth metal tritellurides, high temperature cuprate superconductors, and iron-based superconductors.

  16. EV/PHEV Bidirectional Charger Assessment for V2G Reactive Power Operation

    SciTech Connect

    Kisacikoglu, Mithat C; Ozpineci, Burak; Tolbert, Leon M

    2013-01-01

    This paper presents a summary of the available single-phase ac-dc topologies used for EV/PHEV, level-1 and -2 on-board charging and for providing reactive power support to the utility grid. It presents the design motives of single-phase on-board chargers in detail and makes a classification of the chargers based on their future vehicle-to-grid usage. The pros and cons of each different ac-dc topology are discussed to shed light on their suitability for reactive power support. This paper also presents and analyzes the differences between charging-only operation and capacitive reactive power operation that results in increased demand from the dc-link capacitor (more charge/discharge cycles and increased second harmonic ripple current). Moreover, battery state of charge is spared from losses during reactive power operation, but converter output power must be limited below its rated power rating to have the same stress on the dc-link capacitor.

  17. Thermophysical properties of near-Earth asteroid (341843) 2008 EV5 from WISE data

    NASA Astrophysics Data System (ADS)

    Alí-Lagoa, V.; Lionni, L.; Delbo, M.; Gundlach, B.; Blum, J.; Licandro, J.

    2014-01-01

    Aims: We derive the thermal inertia of 2008 EV5, the baseline target for the Marco Polo-R mission proposal, and infer information about the size of the particles on its surface. Methods: Values of thermal inertia were obtained by fitting an asteroid thermophysical model to NASA's Wide-field Infrared Survey Explorer (WISE) infrared data. Grain size was derived from the constrained thermal inertia and a model of heat conductivity that accounts for different values of the packing fraction (a measure of the degree of compaction of the regolith particles). Results: We obtain an effective diameter D = 370 ± 6 m, geometric visible albedo pV = 0.13 ± 0.05 (assuming H = 20.0 ± 0.4), and thermal inertia Γ = 450 ± 60 J m-2 s-1/2 K-1 at the 1σ level of significance for its retrograde spin-pole solution. The regolith particles radius is r = 6.6+1.3-1.3 mm for low degrees of compaction and r = 12.5+2.7-2.6 mm for the highest packing densities. Table of observed fluxes is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/561/A45

  18. Linear Covariance Analysis For Proximity Operations Around Asteroid 2008 EV5

    NASA Technical Reports Server (NTRS)

    Wright, Cinnamon A.; Bhatt, Sagar; Woffinden, David; Strube, Matthew; D'Souza, Christopher; DeWeese, Keith

    2015-01-01

    The NASA initiative to collect an asteroid the Asteroid Robotic Redirect Mission (ARRM) is currently investigating the option of retrieving a boulder off an asteroid, demonstrating planetary defense with an enhanced gravity tractor technique and returning it to a lunar orbit. Techniques for accomplishing this are being investigated by the Satellite Servicing Capabilities Office (SSOO) and NASA GSFC in colloboration with JPL, NASA, JSC, LaRC, and Draper Laboratories Inc. Two critical phases of the mission are the descent to the boulder and the Enhanced Gravity Tractor-enhanced gravity tractor demonstration. A linear covariance analysis was done for these phases to assess the feasibility of these concepts with the proposed design of the sensor and actuaor suite of the Asteroid Redirect Vehicle (ARV). The sensor suite for this analysis will include a wide field of view camera, Lidar, and a MMU. The proposed asteroid of interest is currently the C-type asteroid 2008 EV5, a carbonaceous chondrite that is of high interest to the scientific community. This paper will present an overview of the analysis discuss sensor and actuator models and address the feasibility of descending to the boulder within the requirements as the feasibility of maintaining the halo orbit in order to demonstrate the Enhanced Gravity Tractor-enhanced gravity tractory technique.

  19. Asteroid Redirect Mission Proximity Operations for Reference Target Asteroid 2008 EV5

    NASA Technical Reports Server (NTRS)

    Reeves, David M.; Mazanek, Daniel D.; Cichy, Benjamin D.; Broschart, Steve B.; Deweese, Keith D.

    2016-01-01

    NASA's Asteroid Redirect Mission (ARM) is composed of two segments, the Asteroid Redirect Robotic Mission (ARRM), and the Asteroid Redirect Crewed Mission (ARCM). In March of 2015, NASA selected the Robotic Boulder Capture Option1 as the baseline for the ARRM. This option will capture a multi-ton boulder, (typically 2-4 meters in size) from the surface of a large (greater than approx.100 m diameter) Near-Earth Asteroid (NEA) and return it to cis-lunar space for subsequent human exploration during the ARCM. Further human and robotic missions to the asteroidal material would also be facilitated by its return to cis-lunar space. In addition, prior to departing the asteroid, the Asteroid Redirect Vehicle (ARV) will perform a demonstration of the Enhanced Gravity Tractor (EGT) planetary defense technique2. This paper will discuss the proximity operations which have been broken into three phases: Approach and Characterization, Boulder Capture, and Planetary Defense Demonstration. Each of these phases has been analyzed for the ARRM reference target, 2008 EV5, and a detailed baseline operations concept has been developed.

  20. More Efficient Power Conversion for EVs: Gallium-Nitride Advanced Power Semiconductor and Packaging

    SciTech Connect

    2010-02-01

    Broad Funding Opportunity Announcement Project: Delphi is developing power converters that are smaller and more energy efficient, reliable, and cost-effective than current power converters. Power converters rely on power transistors which act like a very precisely controlled on-off switch, controlling the electrical energy flowing through an electrical circuit. Most power transistors today use silicon (Si) semiconductors. However, Delphi is using semiconductors made with a thin layer of gallium-nitride (GaN) applied on top of the more conventional Si material. The GaN layer increases the energy efficiency of the power transistor and also enables the transistor to operate at much higher temperatures, voltages, and power-density levels compared to its Si counterpart. Delphi is packaging these high-performance GaN semiconductors with advanced electrical connections and a cooling system that extracts waste heat from both sides of the device to further increase the device’s efficiency and allow more electrical current to flow through it. When combined with other electronic components on a circuit board, Delphi’s GaN power transistor package will help improve the overall performance and cost-effectiveness of HEVs and EVs.

  1. 1-eV GaInNAs solar cells for ultrahigh-frequency multijunction devices

    SciTech Connect

    Friedman, D.J.; Geisz, J.F.; Kurtz, S.R.; Olson, J.M.

    1998-09-01

    The authors demonstrate working prototypes of a GaInNAs-based solar cell lattice-matched to GaAs with photoresponse down to 1 eV. This device is intended for use as the third junction of future-generation ultrahigh-efficiency three- and four-junction devices. Under the AM1.5 direct spectrum with all the light higher in energy than the GaAs band gap filtered out, the prototypes have open-circuit voltages ranging from 0.35 to 0.44 V, short-circuit currents of 1.8 mA/cm{sup 2}, and fill factors from 61--66%. The short-circuit currents are of principal concern: the internal quantum efficiencies rise only to about 0.2. The authors discuss the short diffusion lengths which are the reason for this low photocurrent. As a partial workaround for the poor diffusion lengths, they demonstrate a depletion-width-enhanced variation of one of the prototype devices that grades off decreased voltage for increased photocurrent, with a short-circuit current of 6.5 mA/cm{sup 2} and an open-circuit voltage of 0.29 V.

  2. EvArnoldi: A New Algorithm for Large-Scale Eigenvalue Problems.

    PubMed

    Tal-Ezer, Hillel

    2016-05-19

    Eigenvalues and eigenvectors are an essential theme in numerical linear algebra. Their study is mainly motivated by their high importance in a wide range of applications. Knowledge of eigenvalues is essential in quantum molecular science. Solutions of the Schrödinger equation for the electrons composing the molecule are the basis of electronic structure theory. Electronic eigenvalues compose the potential energy surfaces for nuclear motion. The eigenvectors allow calculation of diople transition matrix elements, the core of spectroscopy. The vibrational dynamics molecule also requires knowledge of the eigenvalues of the vibrational Hamiltonian. Typically in these problems, the dimension of Hilbert space is huge. Practically, only a small subset of eigenvalues is required. In this paper, we present a highly efficient algorithm, named EvArnoldi, for solving the large-scale eigenvalues problem. The algorithm, in its basic formulation, is mathematically equivalent to ARPACK ( Sorensen , D. C. Implicitly Restarted Arnoldi/Lanczos Methods for Large Scale Eigenvalue Calculations ; Springer , 1997 ; Lehoucq , R. B. ; Sorensen , D. C. SIAM Journal on Matrix Analysis and Applications 1996 , 17 , 789 ; Calvetti , D. ; Reichel , L. ; Sorensen , D. C. Electronic Transactions on Numerical Analysis 1994 , 2 , 21 ) (or Eigs of Matlab) but significantly simpler. PMID:27015379

  3. Production data on 0.55 eV InGaAs thermophotovoltaic cells

    SciTech Connect

    Wojtzuk, S.; Colter, P.; Charache, G.; Campbell, B.

    1996-05-01

    Low bandgap 0.55 eV (2.25 {micro}m cutoff wavelength) indium gallium arsenide (In{sub 0.72}Ga{sub 0.28}As) thermophotovoltaic (TPV) cells use much more of the long wavelength energy emitted from low temperature (< 1,200 C) thermal sources than either Si or GaSb cells. Data are presented on a statistically significant number (2,500) of these TPV cells, indicating the performance obtainable in large numbers of cells. This data should be useful in the design and modeling of TPV system performance. At 1.2 A/cm{sup 2} short-circuit current, an average open-circuit voltage of 283 mV is obtained with a 60% fill factor. The peak external quantum efficiency for uncoated cells is 65% and is over 50% from 1.1 to 2.2 {micro}m. Internal quantum efficiency is over 76% in this range assuming an estimated 34% reflectance loss.

  4. Development of a nickel/metal hydride battery (Ni/MH) system for EV application

    SciTech Connect

    Ikoma, M.; Hamada, S.; Morishita, N.; Hoshina, Y.; Matsuda, H.; Ohta, K.; Kimura, T.

    1994-12-31

    In order to satisfy basic battery characteristics for electric vehicles (EV) such as specific energy, specific power and cycle life that are required for driving on urban streets, the authors have selected the valve-regulated lead acid battery as a conventional battery and the nickel/metal-hydride battery as an advanced battery, and have been studying their development in order to put them into practical use by 1998. Regarding the nickel/metal-hydride battery, excellent nickel positive electrode with high temperature charge efficiency accomplished with additives such as Ca compounds, and an exceedingly good hydrogen absorbing alloy negative electrode with high capacity and long cycle life, achieved by adjustment of alloy composition, surface treatment, and control of binder and conductive additive have been developed to overcome difficulties in the scale-up of battery size. Modular batteries using this technology possess specific energy twice (70 Wh/kg) that of the lead-acid battery, and have superior specific power (160 Wh/kg) and cycle life. 5 refs.

  5. Collisional-radiative modeling of tungsten at temperatures of 1200–2400 eV

    DOE PAGESBeta

    Colgan, James; Fontes, Christopher; Zhang, Honglin; Abdallah, Jr., Joseph

    2015-04-30

    We discuss new collisional-radiative modeling calculations of tungsten at moderate temperatures of 1200 to 2400 eV. Such plasma conditions are relevant to ongoing experimental work at ASDEX Upgrade and are expected to be relevant for ITER. Our calculations are made using the Los Alamos National Laboratory (LANL) collisional-radiative modeling ATOMIC code. These calculations formed part of a submission to the recent NLTE-8 workshop that was held in November 2013. This series of workshops provides a forum for detailed comparison of plasma and spectral quantities from NLTE collisional-radiative modeling codes. We focus on the LANL ATOMIC calculations for tungsten that weremore » submitted to the NLTE-8 workshop and discuss different models that were constructed to predict the tungsten emission. In particular, we discuss comparisons between semi-relativistic configuration-average and fully relativistic configuration-average calculations. We also present semi-relativistic calculations that include fine-structure detail, and discuss the difficult problem of ensuring completeness with respect to the number of configurations included in a CR calculation.« less

  6. Plasma Sputter-type Ion Source with Wire Electrodes for Low-energy Gallium Ion Extraction

    SciTech Connect

    Vasquez, M. Jr.; Kasuya, T.; Wada, M.; Maeno, S.; Miyamoto, N.

    2011-01-07

    Low-energy ions of gallium (Ga) and argon (Ar) were extracted from a plasma sputter-type ion source system that utilized a tungsten (W) wire extractor geometry. The 90% transparent W wire extractor configuration had shown that the system was capable of producing an ion beam with the energy as low as 10 eV in a dc filament discharge and 50 eV in a radio frequency (rf) excited system. In the present investigation, Ar plasma was sustained in an ion source chamber through an inductively coupled 13.56 MHz rf power source. Negatively biased liquid Ga target suspended on a W reservoir was sputtered and postionized prior to extraction. Mass spectral analyses revealed a strong dependence of the Ga{sup +} current on the induced target bias.

  7. 0.7-eV GaInAs Junction for a GaInP/GaAs/GaInAs(1eV)/GaInAs(0.7eV) Four-Junction Solar Cell

    SciTech Connect

    Friedman, D. J.; Geisz, J. F.; Norman, A. G.; Wanlass, M. W.; Kurtz, S. R.

    2006-01-01

    We discuss recent developments in III-V multijunction solar cells, focusing on adding a fourth junction to the Ga{sub 0.5}In{sub 0.5} P/GaAs/Ga{sub 0.75}In{sub 0.25}As inverted three-junction cell. This cell, grown inverted on GaAs so that the lattice-mismatched Ga{sub 0.75}In{sub 0.25}As third junction is the last one grown, has demonstrated 38% efficiency, and 40% is likely in the near future. To achieve still further gains, a lower-bandgap Ga{sub x}In{sub 1-x}As fourth junction could be added to the three-junction structure for a four-junction cell whose efficiency could exceed 45% under concentration. Here, we present the initial development of the Ga{sub x}In{sub 1-x}As fourth junction. Junctions of various bandgaps ranging from 0.88 to 0.73 eV were grown, in order to study the effect of the different amounts of lattice mismatch. At a bandgap of 0.88 eV, junctions were obtained with very encouraging {approx}80% quantum efficiency, 57% fill factor, and 0.36 eV open-circuit voltage. The device performance degrades with decreasing bandgap (i.e., increasing lattice mismatch). We model the four-junction device efficiency vs. fourth junction bandgap to show that an 0.7-eV fourth-junction bandgap, while optimal if it could be achieved in practice, is not necessary; an 0.9-eV bandgap would still permit significant gains in multijunction cell efficiency while being easier to achieve than the lower-bandgap junction.

  8. Mass Spectrometry for the Masses

    ERIC Educational Resources Information Center

    Persinger, Jared D.; Hoops, Geoffrey, C.; Samide, Michael J.

    2004-01-01

    A simple, qualitative experiment is developed for implementation, where the gas chromatography-mass spectrometry (GC-MS) plays an important role, into the laboratory curriculum of a chemistry course designed for nonscience majors. This laboratory experiment is well suited for the students as it helps them to determine the validity of their…

  9. /sup 187/Os + n resonance parameters in the interval 27-500 eV neutron energies

    SciTech Connect

    Winters, R.R.; Carlton, R.F.; Harvey, J.A.; Hill, N.W.

    1982-01-01

    The neutron total cross section for /sup 187/Os, in the energy range, 27 eV to 500 eV, has been measured at the ORELA facility by the neutron time-of-flight technique, utilizing a 2.0 gm osmium sample (n = 0.008401 Os-nuclei/barn) enriched to 70.38% /sup 187/Os. Measurements were performed at a 80 m flight station with an energy resolution, ..delta..E/E, of 0.1% using a /sup 6/Li glass scintillator. Resolved resonances have been analyzed by a Reich-Moore multilevel code (SAMMY) to obtain parameters for 85 resonances up to 500 eV. Preliminary determinations of the level spacing (5 eV) and s-wave strength function (3.9 x 10/sup -4/) for /sup 187/Os are in agreement with recent analyses of the osmium isotopes, made in connection with the use of the Re/Os chronometer for estimating the duration of stellar nucleosynthesis.

  10. An ultrahigh-vacuum apparatus for resonant diffraction experiments using soft x rays (hnu=300-2000 eV).

    PubMed

    Takeuchi, T; Chainani, A; Takata, Y; Tanaka, Y; Oura, M; Tsubota, M; Senba, Y; Ohashi, H; Mochiku, T; Hirata, K; Shin, S

    2009-02-01

    We have developed an ultrahigh-vacuum instrument for resonant diffraction experiments using polarized soft x rays in the energy range of hnu=300-2000 eV at beamline BL17SU of SPring-8. The diffractometer consists of modified differentially pumped rotary feedthroughs for theta-2theta stages, a sample manipulator with motor-controlled x-y-z-, tilt (chi)-, and azimuth (phi)-axes, and a liquid helium flow-type cryostat for temperature dependent measurements between 30 and 300 K. Test results indicate that the diffractometer exhibits high reproducibility (better than 0.001 degrees ) for a Bragg reflection of alpha-quartz 100 at a photon energy of hnu=1950 eV. Typical off- and on-resonance Bragg reflections in the energy range of 530-1950 eV could be measured using the apparatus. The results show that x-ray diffraction experiments with energy-, azimuth-, and incident photon polarization-dependence can be reliably measured using soft x rays in the energy range of approximately 300-2000 eV. The facility can be used for resonant diffraction experiments across the L-edge of transition metals, M-edge of lanthanides, and up to the Si K-edge of materials. PMID:19256660

  11. Si-Ge-Sn alloys with 1.0 eV gap for CPV multijunction solar cells

    SciTech Connect

    Roucka, Radek Clark, Andrew; Landini, Barbara

    2015-09-28

    Si-Ge-Sn ternary group IV alloys offer an alternative to currently used 1.0 eV gap materials utilized in multijunction solar cells. The advantage of Si-Ge-Sn is the ability to vary both the bandgap and lattice parameter independently. We present current development in fabrication of Si-Ge-Sn alloys with gaps in the 1.0 eV range. Produced material exhibits excellent structural properties, which allow for integration with existing III-V photovoltaic cell concepts. Time dependent room temperature photoluminescence data demonstrate that these materials have long carrier lifetimes. Absorption tunable by compositional changes is observed. As a prototype device set utilizing the 1 eV Si-Ge-Sn junction, single junction Si-Ge-Sn device and triple junction device with Si-Ge-Sn subcell have been fabricated. The resulting I-V and external quantum efficiency data show that the Si-Ge-Sn junction is fully functional and the performance is comparable to other 1.0 eV gap materials currently used.

  12. What Kind of Charging Infrastructure Do Chevrolet Volt Drivers in The EV Project Use and When Do They Use It?

    SciTech Connect

    Shawn Salisbury

    2014-09-01

    This document will present information describing the charging behavior of Chevrolet Volts that were enrolled in the EV Project. It will included aggregated data from more than 1,800 vehicles regarding locations, power levels, and time-of-day of charging events performed by those vehicles. This document will be published to the INL AVTA website.

  13. Potential Estimation of Hourly Blank Storage Space and Charge Loads of EVs using Road Traffic Census and Vehicles Status

    NASA Astrophysics Data System (ADS)

    Oda, Takuya; Ito, Masakazu; Kawasaki, Norihiro; Miyazaki, Takahiko; Kashiwagi, Takao

    If both EVs (Electric Vehicles, includes plug-in hybrid electric vehicles) and renewable energies spread in large quantities, it is possible to control the supply fluctuation of renewable energies using the storage battery of EVs. This research tried to show the charge load potential of EVs based on the state of the Japanese passenger car using traffic census results etc. Furthermore, it tried to show trend of the storage battery capacity according to time. From the estimated result; (1) the charge electricity of low and middle distance gets a majority of the total charge demand, (2) charge load changes according to time several times, and the minimum load is the number of GWh at early morning, (3) if night charge is assumed, the standby charge demand of noon will reach tens GWh, it may have sufficient scale for supply fluctuation control of PVs. Although the present EV is not suitable for long-distance running, these are expected to be 30 or less percent of the total charge demand. The estimated storage capacity potential in this research will not change numbers of times.

  14. Mass Sensor

    SciTech Connect

    Adams, B.E.

    2001-01-18

    The purpose of this CRADA was to use Honeywell's experience in low temperature cofire ceramics and traditional ceramics to assemble a relatively low-cost, mass-producible miniature mass analyzer. The specific design, given to us by Mass Sensors, LLC, was used to test for helium. The direct benefit for the participant was to have a prototype unit assembled for the purpose of proof of concept and the ability to secure venture capital investors. From that, the company would begin producing their own product for sale. The consumer/taxpayer benefits come from the wide variety of industries that can utilize this technology to improve quality of life. Medical industry can use this technology to improve diagnostic ability; manufacturing industry can use it for improved air, water, and soil monitoring to minimize pollution; and the law enforcement community can use this technology for identification of substances. These are just a few examples of the benefit of this technology. The benefits to DOE were in the area of process improvement for cofire and ceramic materials. From this project we demonstrated nonlinear thickfilm fine lines and spaces that were 5-mil wide with 5-mil spaces; determined height-to diameter-ratios for punched and filled via holes; demonstrated the ability to punch and fill 5-mil microvias; developed and demonstrated the capability to laser cut difficult geometries in 40-mil ceramic; developed and demonstrated coupling LTCC with standard alumina and achieving hermetic seals; developed and demonstrated three-dimensional electronic packaging concepts; and demonstrated printing variable resistors within 1% of the nominal value and within a tightly defined ratio. The capability of this device makes it invaluable for many industries. The device could be used to monitor air samples around manufacturing plants. It also could be used for monitoring automobile exhaust, for doing blood gas analysis, for sampling gases being emitted by volcanoes, for studying

  15. Phosphodiester and N-glycosidic bond cleavage in DNA induced by 4-15 eV electrons

    NASA Astrophysics Data System (ADS)

    Zheng, Yi; Cloutier, Pierre; Hunting, Darel J.; Wagner, J. Richard; Sanche, Léon

    2006-02-01

    Thin molecular films of the short single strand of DNA, GCAT, were bombarded under vacuum by electrons with energies between 4 and 15 eV. Ex vacuo analysis by high-pressure liquid chromatography of the samples exposed to the electron beam revealed the formation of a multitude of products. Among these, 12 fragments of GCAT were identified by comparison with reference compounds and their yields were measured as a function of electron energy. For all energies, scission of the backbone gave nonmodified fragments containing a terminal phosphate, with negligible amounts of fragments without the phosphate group. This indicates that phosphodiester bond cleavage by 4-15 eV electrons involves cleavage of the C-O bond rather than the P-O bond. The yield functions exhibit maxima at 6 and 10-12 eV, which are interpreted as due to the formation of transient anions leading to fragmentation. Below 15 eV, these resonances dominate bond dissociation processes. All four nonmodified bases are released from the tetramer, by cleavage of the N-glycosidic bond, which occurs principally via the formation of core-excited resonances located around 6 and 10 eV. The formation of the other nonmodified products leading to cleavage of the phosphodiester bond is suggested to occur principally via two different mechanisms: (1) the formation of a core-excited resonance on the phosphate unit followed by dissociation of the transient anion and (2) dissociation of the CO bond of the phosphate group formed by resonance electron transfer from the bases. In each case, phosphodiester bond cleavage leads chiefly to the formation of stable phosphate anions and sugar radicals with minimal amounts of alkoxyl anions and phosphoryl radicals.

  16. Validation-based insertional mutagenesis for identification of Nup214 as a host factor for EV71 replication in RD cells

    SciTech Connect

    Wang, Bei; Zhang, XiaoYu; Zhao, Zhendong

    2013-08-02

    Highlights: •We introduced a new mutagenesis strategy named VBIM to the viral research. •This method can identify either host factors or host restriction factors. •Using VBIM system, we identified Nup214 as a host factor for EV71 replication in RD cells. -- Abstract: Lentiviral validation-based insertional mutagenesis (VBIM) is a sophisticated, forward genetic approach that is used for the investigation of signal transduction in mammalian cells. Using VBIM, we conducted function-based genetic screening for host genes that affect enterovirus 71 (EV71) viral replication. This included host factors that are required for the life cycle of EV71 and host restriction factors that inhibit EV71 replication. Several cell clones, resistant to EV71, were produced using EV71 infection as a selection pressure and the nuclear pore protein 214 (Nup214) was identified as a host factor required for EV71 replication. In SD2-2, the corresponding VBIM lentivirus transformed clone, the expression of endogenous Nup214 was significantly down-regulated by the reverse inserted VBIM promoter. After Cre recombinase-mediated excision of the VBIM promoter, the expression of Nup214 recovered and the clone regained sensitivity to the EV71 infection. Furthermore, over-expression of Nup214 in the cells suggested that Nup214 was promoting EV71 replication. Results of this study indicate that a successful mutagenesis strategy has been established for screening host genes related to viral replication.

  17. Imaging the Heliosphere Using Neutral Atoms from Solar Wind Energy Down to 15 eV

    NASA Astrophysics Data System (ADS)

    Galli, A.; Wurz, P.; Fuselier, S. A.; McComas, D. J.; Bzowski, M.; Sokół, J. M.; Kubiak, M. A.; Möbius, E.

    2014-11-01

    We study the spatial and temporal distribution of hydrogen energetic neutral atoms (ENAs) from the heliosheath observed with the IBEX-Lo sensor of the Interstellar Boundary EXplorer (IBEX) from solar wind energies down to the lowest available energy (15 eV). All available IBEX-Lo data from 2009 January until 2013 June were included. The sky regions imaged when the spacecraft was outside of Earth's magnetosphere and when the Earth was moving toward the direction of observation offer a sufficient signal-to-noise ratio even at very low energies. We find that the ENA ribbon—a 20° wide region of high ENA intensities—is most prominent at solar wind energies whereas it fades at lower energies. The maximum emission in the ribbon is located near the poles for 2 keV and closer to the ecliptic plane for energies below 1 keV. This shift is an evidence that the ENA ribbon originates from the solar wind. Below 0.1 keV, the ribbon can no longer be identified against the globally distributed ENA signal. The ENA measurements in the downwind direction are affected by magnetospheric contamination below 0.5 keV, but a region of very low ENA intensities can be identified from 0.1 keV to 2 keV. The energy spectra of heliospheric ENAs follow a uniform power law down to 0.1 keV. Below this energy, they seem to become flatter, which is consistent with predictions. Due to the subtraction of local background, the ENA intensities measured with IBEX agree with the upper limit derived from Lyα observations.

  18. Exploration of the Black, Aegean, and Mediterranean Seas Aboard E/V Nautilus

    NASA Astrophysics Data System (ADS)

    Bell, K. L.; Ballard, R. D.; Brennan, M. L.; Raineault, N. A.; Shank, T. M.; Mayer, L. A.; Roman, C.; Mitchell, G. A.; Coleman, D. F.

    2012-12-01

    In the summer of 2012, the Exploration Vessel (E/V) Nautilus undertook a two-month expedition to the Black, Aegean, and Mediterranean Seas. The primary goal of the Nautilus is to create a focus of international leadership for the development and integration of leading-edge technologies, educational programs, field operations, and public outreach programs for ocean exploration, in partnership with the NOAA Office of Ocean Exploration, National Geographic Society, Office of Naval Research, and corporate partners. To do so, the program uses a complement of deep submergence vehicle systems and telepresence technologies to engage scientists, educators and the public, both at sea and ashore, allowing them to become integral members of the on-board exploration team. When discoveries are made, experts ashore are notified and brought aboard virtually within a short period of time to help guide shipboard response before the ship moves on. The 2012 expedition is comprised of four areas of interest. Extensive sidescan mapping took place off the Turkish coasts of the southern Black Sea and eastern Aegean Sea, and was followed by remotely operated vehicle (ROV) dives on targets of archaeological, geological, and biological interest. In the Black Sea, additional work was done on the porewater chemistry of the sediments in the oxic, suboxic, and anoxic zones. Nautilus returned to the Anaximander Seamounts, including Kazan, Amserdam, Thessaloniki, and Athina, to further explore active and formerly active seep sites located in 2010. Finally, based on biological and geological discoveries made on Eratosthenes Seamount in the eastern Mediterranean Sea, we returned to further study chemosynthetic vent communities and tectonic processes.;

  19. The Swift/Fermi GRB 080928 from 1 eV to 150 keV

    NASA Technical Reports Server (NTRS)

    Sonbas, Eda; Rossi, A.; Schulze, S.; Klose, S.; Kann, D. A.; Ferrero, P.; NicuesaGuelbenzu, A.; Rau, A.; Kruehler, T.; Greiner, J.; Schady, P.; Afonso, P. M. J.; Clemens, C.; Filgas, R.; KuepcuYoldas, A.; McBreen, S.; Olivares, F.; Szokoly, G.; Yoldas, A.; Krimm, H. A.; Johannesson, G.; Panaitescu, A.; Yuan, F.; Pandey, S. B.; Akerlof, C. W.

    2010-01-01

    We present the results of a comprehensive study of the Gamma-Ray Burst 080928 and of its afterglow. GRB 08092 was a long burst detected by Swift/BAT and Fermi/GBM, It is one of the exceptional cases where optical emission was already detected when the GRB itself was still radiating in the gamma-ray band. for nearly 100 seconds simultaneous optical X-ray and gamma-ray data provide a coverage of the spectral energy distribution of the transient source from about 1 eV to 150 keV. Here we analyze the prompt emission, constrain its spectral propertIes. and set lower limits on the initial Lorentz factor of the relativistic outflow, In particular. we show that the SED during the main prompt emission phase is in agreement with synchrotron radiation. We construct the optical/near-infrared light curve and the spectral energy distribution based on Swift/UVOT. ROTSE-Illa (Australia) and GROND (La Silla) data and compare it to the X-ray light curve retrieved from the Swift/XRT repository. We show that its bumpy shape can be modeled by multiple energy injections into the forward shock. Furthermore, we provide evidence that the temporal and spectral evolution of the first strong flare seen in the early X-ray light curve can be explained by large-angle emission. Finally, we report on the results of our search for the GRB host galaxy, for which only a deep upper limit can be provided.

  20. Imaging the heliosphere using neutral atoms from solar wind energy down to 15 eV

    SciTech Connect

    Galli, A.; Wurz, P.; Fuselier, S. A.; McComas, D. J.; Bzowski, M.; Sokół, J. M.; Kubiak, M. A.; Möbius, E.

    2014-11-20

    We study the spatial and temporal distribution of hydrogen energetic neutral atoms (ENAs) from the heliosheath observed with the IBEX-Lo sensor of the Interstellar Boundary EXplorer (IBEX) from solar wind energies down to the lowest available energy (15 eV). All available IBEX-Lo data from 2009 January until 2013 June were included. The sky regions imaged when the spacecraft was outside of Earth's magnetosphere and when the Earth was moving toward the direction of observation offer a sufficient signal-to-noise ratio even at very low energies. We find that the ENA ribbon—a 20° wide region of high ENA intensities—is most prominent at solar wind energies whereas it fades at lower energies. The maximum emission in the ribbon is located near the poles for 2 keV and closer to the ecliptic plane for energies below 1 keV. This shift is an evidence that the ENA ribbon originates from the solar wind. Below 0.1 keV, the ribbon can no longer be identified against the globally distributed ENA signal. The ENA measurements in the downwind direction are affected by magnetospheric contamination below 0.5 keV, but a region of very low ENA intensities can be identified from 0.1 keV to 2 keV. The energy spectra of heliospheric ENAs follow a uniform power law down to 0.1 keV. Below this energy, they seem to become flatter, which is consistent with predictions. Due to the subtraction of local background, the ENA intensities measured with IBEX agree with the upper limit derived from Lyα observations.

  1. Testing the performance of a VUV photoionization source on a double focussing mass spectrometer using alkanes and thiophenes

    NASA Astrophysics Data System (ADS)

    Bobeldijk, M.; Kistemaker, P. G.; Boon, J. J.

    1991-12-01

    The performance of a newly developed photoionization source in combination with a high resolution mass spectrometer is tested. The total ion currents for several linear alkanes (n-pentane to n-decane) and for some thiophenes (2-methylthiophene, 2,5-dimethylthiophene and 2-ethylthiophene) are measured at three fixed wavelengths: the Kr I (10.03 eV and 10.64 eV), Ar I (11.62 eV and 11.83 eV) and Ne I (16.67 eV and 16.85 eV) resonance lines. These total ion currents are compared with the data for the alkanes and thiophenes obtained with low energy (10.6 eV, 11.8 eV and 16.7eV) electron impact ionization on the same mass spectrometer. The loss in ion intensity at several positions throughout this instrument is determined for the photo-ionization source and for the electron impact ionization source. One out of every 1500 ions created in the photoionization source is measured by the detector. For the electron impact ionization source, one out of 180 ions is measured. The introduction of a five-element "Heddle" lens for the transfer of the ions from the photoion source to the mass analyser resulted in an approximately 1.5 fold loss in ion current. From the measured total ion intensities, the photoionization and electron impact ionization cross-sections at energies of 10.6 eV, 11.8 eV and 16.7 eV are calculated. The photoionization cross-section values of the linear alkanes are found to be in the range of 2.5 Mbarn to 355 Mbarn, and the electron impact ionization cross-section values are between 40 Mbarn and 735 Mbarn. The photoionization cross-section values of the thiophenes range from 4 Mbarn to 31 Mbarn, and the electron impact ionization cross-section values from 81 Mbarn to 760 Mbarn.

  2. MASS SPECTROMETRY

    DOEpatents

    Friedman, L.

    1962-01-01

    method is described for operating a mass spectrometer to improve its resolution qualities and to extend its period of use substantially between cleanings. In this method, a small amount of a beta emitting gas such as hydrogen titride or carbon-14 methane is added to the sample being supplied to the spectrometer for investigation. The additive establishes leakage paths on the surface of the non-conducting film accumulating within the vacuum chamber of the spectrometer, thereby reducing the effect of an accumulated static charge on the electrostatic and magnetic fields established within the instrument. (AEC)

  3. Neutrino mass limits: Robust information from the power spectrum of galaxy surveys

    NASA Astrophysics Data System (ADS)

    Cuesta, Antonio J.; Niro, Viviana; Verde, Licia

    2016-09-01

    We present cosmological upper limits on the sum of active neutrino masses using large-scale power spectrum data from the WiggleZ Dark Energy Survey and from the Sloan Digital Sky Survey - Data Release 7 (SDSS-DR7) sample of Luminous Red Galaxies (LRG). Combining measurements on the Cosmic Microwave Background temperature and polarisation anisotropies by the Planck satellite together with WiggleZ power spectrum results in a neutrino mass bound of 0.37 eV at 95% C.L., while replacing WiggleZ by the SDSS-DR7 LRG power spectrum, the 95% C.L. bound on the sum of neutrino masses is 0.38 eV. Adding Baryon Acoustic Oscillation (BAO) distance scale measurements, the neutrino mass upper limits greatly improve, since BAO data break degeneracies in parameter space. Within a ΛCDM model, we find an upper limit of 0.13 eV (0.14 eV) at 95% C.L., when using SDSS-DR7 LRG (WiggleZ) together with BAO and Planck. The addition of BAO data makes the neutrino mass upper limit robust, showing only a weak dependence on the power spectrum used. We also quantify the dependence of neutrino mass limit reported here on the CMB lensing information. The tighter upper limit (0.13 eV) obtained with SDSS-DR7 LRG is very close to that recently obtained using Lyman-alpha clustering data, yet uses a completely different probe and redshift range, further supporting the robustness of the constraint. This constraint puts under some pressure the inverted mass hierarchy and favours the normal hierarchy.

  4. Mass spectrometry

    SciTech Connect

    Burlingame, A.L.; Baillie, T.A.; Derrick, P.J.

    1986-04-01

    It is the intention of the review to bring together in one source the direction of major developments in mass spectrometry and to illustrate these by citing key contributions from both fundamental and applied research. The Review is intended to provide the reader with a sense of the main currents, their breadth and depth, and probable future directions. It is also intended to provide the reader with a glimpse of the diverse discoveries and results that underpin the eventual development of new methods and instruments - the keys to obtaining new insights in all the physical, chemical, and biological sciences which depend on mass spectrometry at various levels of sophistication. Focal points for future interdisciplinary synergism might be selective quantitative derivatization of large peptides, which would convey properties that direct fragmentation providing specific sequence information, or optimization of LCMS for biooligomer sequencing and mixture analysis, or the perfect way to control or enhance the internal energy of ions of any size, or many others. 1669 references.

  5. Obesity reduces the pro-angiogenic potential of adipose tissue stem cell-derived extracellular vesicles (EVs) by impairing miR-126 content: impact on clinical applications

    PubMed Central

    Togliatto, G; Dentelli, P; Gili, M; Gallo, S; Deregibus, C; Biglieri, E; Iavello, A; Santini, E; Rossi, C; Solini, A; Camussi, G; Brizzi, M F

    2016-01-01

    Background/Objectives: Soluble factors and cell-derived extracellular vesicles (EVs) are crucial tissue repair mediators in cell-based therapy. In the present study, we investigate the therapeutic impact of EVs released by adipose tissue-derived stem cells (ASCs) recovered from obese subjects' visceral and subcutaneous tissues. Methods: ASCs were recovered from 10 obese (oASCs) and 6 non-obese (nASCs) participants and characterized. In selected experiments, nASCs and oASCs were cultured with palmitic acid (PA) or high glucose (HG), respectively. EVs from obese (oEVs) and non-obese (nEVs) subjects' visceral and subcutaneous ASCs were collected after ultracentrifugation and analyzed for their cargo: microRNA-126 (miR-126), vascular endothelial growth factor (VEGF), and matrix metalloproteinase 2 (MMP-2), and for their biological effects on endothelial cells (ECs). Western blotting analysis and loss- and gain-of function experiments were performed. Results: oEVs show impaired angiogenic potential compared with nEVs. This effect depends on EV cargo: reduced content of VEGF, MMP-2 and, more importantly, miR-126. We demonstrate, using gain- and loss-of-function experiments, that this reduced miR-126 content leads to Spred1 upregulation and the inhibition of the extracellular signal–regulated kinase 1/2 mitogen-activated protein kinase pathway in ECs. We also show that PA treatment of nASCs translates into the release of EVs that recapitulate oEV cargo. Moreover, HG treatment of oASCs further reduces miR-126 EV content and EV-mediated in vitro angiogenesis. Finally, impaired pro-angiogenic potential is also detected in EVs released from obese subcutaneous adipose tissue-derived ASCs. Conclusions: These results indicate that obesity impacts on EV pro-angiogenic potential and may raise concerns about the use of adipose tissue-derived EVs in cell-based therapy in the obese setting. PMID:26122028

  6. a Cylindrical Mirror Analyser for Neutrino Mass Measurement.

    NASA Astrophysics Data System (ADS)

    Williams, Simon Shaughan

    Available from UMI in association with The British Library. Requires signed TDF. The design of an electrostatic Cylindrical Mirror Analyser (CMA) for neutrino mass measurement is given. The resolution is 15 eV FWHM, being achieved with second order focusing and tight collimation. The field-matching grids are unique, being sets of accurately positioned vertical wires producing negligible resolution effects. Luminosity is maximised with an extended source and by utilisation of the full 2pi of the CMA. Background is minimised as the deflecting voltage is half the analysing energy so that field--emission can be discriminated against. Cosmic -ray secondaries are largely removed by high resolution silicon surface barrier detectors. The construction of the CMA to an accuracy of ~10 eV in base resolution, and of the magnetic shielding and vacuum systems is outlined. The power supplies and monitoring systems, signal processing electronics and data acquisition software are also described. Ytterbium conversion electron measurements confirm the calculated CMA optical resolution function to better than 10% in half-width. These measurements demonstrate that the CMA calibration and dispersion are at their theoretical values and also identify a small mis-alignment in the CMA, consistent with construction accuracy. Correcting fields are subsequently designed. The end-point spectrum of tritium is measured using a Langmuir-Blodgett mono-layer source, yielding a neutrino mass limit of <64 eV (90% CL), including total resolution systematic error and being limited principally by statistical errors. Tritium measurements also verify the luminosity of the CMA as ~ 9 times 10^ {-4} cm^2 and demonstrate the extremely low background of 2 times 10^{-3} s^{-1} . Monte-Carlo simulations indicate that with this optical resolution, knowledge of molecular final states and energy loss, a lower limit of 10 eV (95% CL) should be measured for a neutrino mass of 30 eV with a suitable source. For a zero

  7. EV Charging Through Wireless Power Transfer: Analysis of Efficiency Optimization and Technology Trends

    SciTech Connect

    Miller, John M; Rakouth, Heri; Suh, In-Soo

    2012-01-01

    This paper is aimed at reviewing the technology trends for wireless power transfer (WPT) for electric vehicles (EV). It also analyzes the factors affecting its efficiency and describes the techniques currently used for its optimization. The review of the technology trends encompasses both stationary and moving vehicle charging systems. The study of the stationary vehicle charging technology is based on current implementations and on-going developments at WiTricity and Oak Ridge National Lab (ORNL). The moving vehicle charging technology is primarily described through the results achieved by the Korean Advanced Institute of Technology (KAIST) along with on-going efforts at Stanford University. The factors affecting the efficiency are determined through the analysis of the equivalent circuit of magnetic resonant coupling. The air gap between both transmitting and receiving coils along with the magnetic field distribution and the relative impedance mismatch between the related circuits are the primary factors affecting the WPT efficiency. Currently the industry is looking at an air gap of 25 cm or below. To control the magnetic field distribution, Kaist has recently developed the Shaped Magnetic Field In Resonance (SMFIR) technology that uses conveniently shaped ferrite material to provide low reluctance path. The efficiency can be further increased by means of impedance matching. As a result, Delphi's implementation of the WiTricity's technology exhibits a WPT efficiency above 90% for stationary charging while KAIST has demonstrated a maximum efficiency of 83% for moving vehicle with its On Line Vehicle (OLEV) project. This study is restricted to near-field applications (short and mid-range) and does not address long-range technology such as microwave power transfer that has low efficiency as it is based on radiating electromagnetic waves. This paper exemplifies Delphi's work in powertrain electrification as part of its innovation for the real world program geared

  8. ATP1B3: a virus-induced host factor against EV71 replication by up-regulating the production of type-I interferons.

    PubMed

    Lu, Yanfang; Hou, Hongyan; Wang, Feng; Qiao, Long; Wang, Xiong; Yu, Jing; Liu, Weiyong; Sun, Ziyong

    2016-09-01

    Enterovirus 71 (EV71) infection can cause severe diseases, and is becoming increasingly common in children. In the current study, we carried out yeast two-hybrid assays to screen human proteins that could interact with 3A protein of EV71. Human β3 subunit of Na(+)/K(+)-ATPase (ATP1B3) protein was demonstrated to interact with the 3A protein of EV71. Although 3A protein had no effect on the expression of ATP1B3, EV71 infection resulted in elevated expression of ATP1B3 in RD cell line, both on messenger RNA (mRNA) and protein levels. Interestingly, knockdown of ATP1B3 could significantly increase the replication of EV71, whereas overexpression of ATP1B3 significantly suppressed the replication of EV71 in RD cells. Furthermore, we demonstrated that the expression of ATP1B3 could induce the production of type-I interferons. Our study demonstrated that ATP1B3 inhibit EV71 replication by enhancing the production of type-I interferons, which could act as a potential therapeutic target in EV71 infection. PMID:27240146

  9. Development of Markov Chain-Based Queuing Model and Wireless Infrastructure for EV to Smart Meter Communication in V2G

    NASA Astrophysics Data System (ADS)

    Santoshkumar; Udaykumar, R. Y.

    2015-04-01

    The electrical vehicles (EVs) can be connected to the grid for power transaction. The vehicle-to-grid (V2G) supports the grid requirements and helps in maintaining the load demands. The grid control center (GCC), aggregator and EV are three key entities in V2G communication. The GCC sends the information about power requirements to the aggregator. The aggregator after receiving the information from the GCC sends the information to the EVs. Based on the information, the interested EV owners participate in power transaction with the grid. The aggregator facilitates the EVs by providing the parking and charging slot. In this paper the queuing model for EVs connected to the grid and development of wireless infrastructure for the EV to Smart Meter communication is proposed. The queuing model is developed and simulated. The path loss models for WiMAX are analyzed and compared. Also, the physical layer of WiMAX protocol is modeled and simulated for the EV to Smart Meter communication in V2G.

  10. Magneto-optical properties of Fe-Pt alloy films in the range 1.55-10.5 eV

    NASA Astrophysics Data System (ADS)

    Sugimoto, Toshio; Katayama, Toshikazu; Suzuki, Yoshishige; Koide, Tsuneharu; Sidara, Tetsuo; Yuri, Masatada; Itoh, Akiyoshi; Kawanishi, Kenji

    1993-12-01

    The optical and magneto-optical properties of as-deposited and annealed Fe51Pt49 films were investigated in the photon energy range 1.55-10.5 eV. The magneto-optical Kerr rotation (θK) spectra of both films were found to show a dispersion-type structure in the 4.6-7.8 eV region: they have large negative and broad positive peaks at around 4.8 and 7.8 eV, respectively. The θK spectra showed a tendency that is essentially quite similar to that of bulk Fe. The Kerr ellipticity (ηK) spectra are bell shaped, exhibiting a large negative peak at 6.3 eV. Plasma edges were observed at 6.9 eV for the as-deposited film and at 7.3 eV for the annealed film. The absolute value of the real part of the off-diagonal dielectric element (ɛ'XY) of both films at ~4.8 eV are almost the same as that of bulk Fe. This leads to the conclusion that the θK enhancement at 4.8 eV is mainly due to a decrease in ɛ''XX and a peak shift in ɛ'XY towards lower energy, but not to a plasma-resonance effect.

  11. Alternate Multilayer Gratings with Enhanced Diffraction Efficiency in the 500-5000 eV Energy Domain

    NASA Astrophysics Data System (ADS)

    Polack, François; Lagarde, Bruno; Idir, Mourad; Cloup, Audrey Liard; Jourdain, Erick; Roulliay, Marc; Delmotte, Franck; Gautier, Julien; Ravet-Krill, Marie-Françoise

    2007-01-01

    An alternate multilayer (AML) grating is a 2 dimensional diffraction structure formed on an optical surface, having a 0.5 duty cycle in the in-plane and in the in-depth direction. It can be made by covering a shallow depth laminar grating with a multilayer stack. We show here that their 2D structure confer AML gratings a high angular and energetic selectivity and therefore enhanced diffraction properties, when used in grazing incidence. In the tender X-ray range (500eV - 5000 eV) they behave much like blazed gratings. Over 15% efficiency has been measured on a 1200 lines/mm Mo/Si AML grating in the 1.2 - 1.5 keV energy range. Computer simulations show that selected multilayer materials such as Cr/C should allow diffraction efficiency over 50% at photon energies over 3 keV.

  12. Cosmic rays around 1018 eV: Implications of contemporary measurements on the origin of the ankle feature

    NASA Astrophysics Data System (ADS)

    Deligny, Olivier

    2014-04-01

    The impressive power-law decay of the energy spectrum of cosmic rays over more than thirty orders of magnitude in intensity and for energies ranging over eleven decades between ≃109 eV and ≃1020 eV is actually dotted with small irregularities. These irregularities are highly valuable for uncovering and understanding the modes of production and propagation of cosmic rays. They manifest themselves through changes in the spectral index characterising the observed power laws. One of these irregularities, known as the ankle, is subject to conflicting interpretations for many years. If contemporary observations characterising it have shed new lights, they are still far from being able to deliver all the story. The purpose of this contribution is to give an overview of the physics of cosmic rays in the energy range where the transition between Galactic and extragalactic cosmic rays is expected to occur, and to deliver several lines of thought about the origin of the ankle.

  13. [Anesthetic Management Using Transesophageal Echocardiography and EV1000 in a Patient with Ebstein's Anomary Undergoing Scoliosis Surgery].

    PubMed

    Tanimura, Kazuki; Miura, Yukiko; Ishii, Hisanari

    2016-02-01

    An 18-year-old female patinet with Ebstein anomaly underwent surgical repair of scoliosis under total intravenous anesthesia. In addtition to normal monitors, we used transesophageal echocardiography (TEE) and EV1000 (Edwards Lifesciences, Irvine, USA), which show stroke volume variation and stroke volume index simultaneously in a rectangular coordinates. TEE detected reversal of intracardiac shunt which caused SpO2 decrease during fixing screws at thoracic vertebrae, then manual ventilation with oxygen unproved SpO2. Because of a high venous pressure due to Ebstein anomaly, surgical bleeding seemed to be larger than usual. By using EV1000, volume status and cardiac contractility were estimated and adequate volume loading and inoptrope injection were performed to stabilize circulatory condition. The operation was completed without any cardiac and respiratory complications. PMID:27017770

  14. Angular Resolution of an EAS Array for Gamma Ray Astronomy at Energies Greater Than 5 x 10 (13) Ev

    NASA Technical Reports Server (NTRS)

    Apte, A. R.; Gopalakrishnan, N. V.; Tonwar, S. C.; Uma, V.

    1985-01-01

    A 24 detector extensive air shower array is being operated at Ootacamund (2300 m altitude, 11.4 deg N latitude) in southern India for a study of arrival directions of showers of energies greater than 5 x 10 to the 13th power eV. Various configurations of the array of detectors have been used to estimate the accuracy in determination of arrival angle of showers with such an array. These studies show that it is possible to achieve an angular resolution of better than 2 deg with the Ooty array for search for point sources of Cosmic gamma rays at energies above 5 x 10 to the 13th power eV.

  15. Differential, integral, and momentum-transfer cross sections for elastic electron scattering by neon - 5 to 100 eV

    NASA Technical Reports Server (NTRS)

    Register, D. F.; Trajmar, S.

    1984-01-01

    Relative elastic-scattering differential cross sections were measured in the 5-100-eV impact energy and 10-145 deg angular ranges. Normalization of these cross sections was achieved by utilizing accurate total electron-scattering cross sections. A phase-shift analysis of the angular distributions in terms of real phase shifts has been carried out. From the differential cross sections, momentum-transfer cross sections were obtained and the values of the critical energy and angle were established (associated with the lowest value of the differential cross section) as 62.5 + or - 2.5 eV and 101.7 deg + or - 1.5 deg, respectively. The present phase shifts, the critical parameters, and differential, integral, and momentum-transfer cross sections are compared to previous experimental and theoretical results. The error associated with the present data is about 10 percent.

  16. Resonance ionization spectroscopy of thorium isotopes-towards a laser spectroscopic identification of the low-lying 7.6 eV isomer of 229Th

    NASA Astrophysics Data System (ADS)

    Raeder, S.; Sonnenschein, V.; Gottwald, T.; Moore, I. D.; Reponen, M.; Rothe, S.; Trautmann, N.; Wendt, K.

    2011-08-01

    In-source resonance ionization spectroscopy was used to identify an efficient and selective three-step excitation/ionization scheme of thorium, suitable for titanium:sapphire (Ti:sa) lasers. The measurements were carried out in the preparation of laser spectroscopic investigations for an identification of the low-lying 229mTh isomer predicted at 7.6 ± 0.5 eV above the nuclear ground state. Using a sample of 232Th, a multitude of optical transitions leading to over 20 previously unknown intermediate states of even parity as well as numerous high-lying odd parity auto-ionizing (AI) states were identified. Level energies were determined with an accuracy of 0.06 cm-1 for intermediate and 0.15 cm-1 for AI states. Using different excitation pathways, an assignment of total angular momenta for several energy levels was possible. One particularly efficient ionization scheme of thorium, exhibiting saturation in all three optical transitions, was studied in detail. For all three levels in this scheme, the isotope shifts of the isotopes 228Th, 229Th and 230Th relative to 232Th were measured. An overall efficiency including ionization, transport and detection of 0.6% was determined, which was predominantly limited by the transmission of the mass spectrometer ion optics.

  17. Calibrating image plate sensitivity in the 700 to 5000 eV spectral energy range

    NASA Astrophysics Data System (ADS)

    Haugh, Michael J.; Lee, Joshua; Romano, Edward; Schneider, Marilyn

    2013-09-01

    This paper describes a method to calibrate image plate sensitivity for use in the low energy spectral range. Image plates, also known as photostimulable luminescence (PSL) detectors, have often proved to be a valuable tool as a detector for plasma physics studies. Their advantages of large dynamic range, high stopping power, and resistance to neutron damage sometimes outweigh the problems of limited resolution and the remote processing required. The neutron damage resistance is required when the X-ray source is producing a high neutron flux. The Static X-ray Imager (SXI) is a key diagnostic on the National Ignition Facility (NIF) target chamber at LLNL for use in determining the symmetry of the laser beams. The SXI is essential to proper interpretation of the data from the Dante diagnostic to determine the X-ray radiation temperature. It is comprised of two diagnostics located at the top and the bottom of the target chamber. The usual detector is a large array CCD camera. For shots giving high yields of neutrons, the camera would not only be blinded by the neutrons, it would be damaged. To get around this problem, an image plate (IP) is used as the detector. The NIF application covers the energy range from 700 to 5000 eV. The type of image plates typically used for plasma physics are the Fuji BAS-MS, BAS-SR, and BAS-TR models. All models consist of an X-ray sensitive material made of BaF(Br,I):Eu2+ embedded in a plastic binder. X-rays incident on the phosphor ionize the Eu 2+ producing Eu3+ and free electrons that are trapped in lattice defects (F-centers) produced by the absence of halogen ions in the BaF2 crystal. An image plate readout scanner irradiates the IP with a red laser causing reduction of the Eu3+ and emission of a blue photon. The photon is collected using a photomultiplier and digitized to make an electronic image. Image plates are cleared of all F-centers by putting them under a bright light for about 10 minutes. They are then ready for producing a

  18. Search for discrete gamma-ray sources emitting at energies greater than 10/sup 15/ eV

    SciTech Connect

    Samorski, M.; Stamm, W.

    1984-02-15

    The data of the extensive air shower experiment at Kiel have been scanned systematically for possible discrete ..gamma..-ray sources in the energy range E>10/sup 15/ eV and in the declination band delta = 25/sup 0/-75/sup 0/. Photon fluxes for celestial positions with the statistically most significant excesses of showers and 3 sigma upper limit photon fluxes for COS B ..gamma..-ray sources visible to the extensive air shower experiment at Kiel are presented.

  19. High brightness InP micropillars grown on silicon with Fermi level splitting larger than 1 eV.

    PubMed

    Tran, Thai-Truong D; Sun, Hao; Ng, Kar Wei; Ren, Fan; Li, Kun; Lu, Fanglu; Yablonovitch, Eli; Chang-Hasnain, Constance J

    2014-06-11

    The growth of III-V nanowires on silicon is a promising approach for low-cost, large-scale III-V photovoltaics. However, performances of III-V nanowire solar cells have not yet been as good as their bulk counterparts, as nanostructured light absorbers are fundamentally challenged by enhanced minority carriers surface recombination rates. The resulting nonradiative losses lead to significant reductions in the external spontaneous emission quantum yield, which, in turn, manifest as penalties in the open-circuit voltage. In this work, calibrated photoluminescence measurements are utilized to construct equivalent voltage-current characteristics relating illumination intensities to Fermi level splitting ΔF inside InP microillars. Under 1 sun, we show that splitting can exceed ΔF ∼ 0.90 eV in undoped pillars. This value can be increased to values of ΔF ∼ 0.95 eV by cleaning pillar surfaces in acidic etchants. Pillars with nanotextured surfaces can yield splitting of ΔF ∼ 0.90 eV, even though they exhibit high densities of stacking faults. Finally, by introducing n-dopants, ΔF of 1.07 eV can be achieved due to a wider bandgap energy in n-doped wurzite InP, the higher brightness of doped materials, and the extraordinarily low surface recombination velocity of InP. This is the highest reported value for InP materials grown on a silicon substrate. These results provide further evidence that InP micropillars on silicon could be a promising material for low-cost, large-scale solar cells with high efficiency. PMID:24841253

  20. PHEV/EV Li-Ion Battery Second-Use Project, NREL (National Renewable Energy Laboratory) (Poster)

    SciTech Connect

    Newbauer, J.; Pesaran, A.

    2010-05-01

    Plug-in hybrid electric vehicles (PHEVs) and full electric vehicles (Evs) have great potential to reduce U.S. dependence on foreign oil and emissions. Battery costs need to be reduced by ~50% to make PHEVs cost competitive with conventional vehicles. One option to reduce initial costs is to reuse the battery in a second application following its retirement from automotive service and offer a cost credit for its residual value.

  1. Neutrinos of energy approximately 10(16) eV from gamma-ray bursts in pulsar wind bubbles.

    PubMed

    Guetta, Dafne; Granot, Jonathan

    2003-05-23

    The supranova model for gamma-ray bursts (GRBs) is becoming increasingly more popular. In this scenario the GRB occurs weeks to years after a supernova explosion, and is located inside a pulsar wind bubble (PWB). Protons accelerated in the internal shocks that emit the GRB may interact with the external PWB photons producing pions which decay into approximately 10(16) eV neutrinos. A km(2) neutrino detector would observe several events per year correlated with the GRBs. PMID:12785881

  2. Absolute total cross-sections for the scattering of 2-18-eV electrons by cesium atoms

    NASA Astrophysics Data System (ADS)

    Jaduszliwer, B.; Chan, Y. C.

    1992-01-01

    An atomic-recoil technique in a scattering-out mode is used to measure absolute total cross sections for the scattering of electrons by cesium atoms between 2 and 18 eV. A comparison of the results with those obtained by Visconti, Slevin, and Rubin (1971) indicate that the close-coupling calculations have yielded total cross sections which are consistently high over the covered energy range.

  3. Cross sections for 14-eV e-H{sub 2} resonant collisions: Dissociative electron attachment

    SciTech Connect

    Celiberto, R.; Janev, R. K.; Wadehra, J. M.; Laricchiuta, A.

    2009-07-15

    The dissociative electron attachment (DEA) process in electron-H{sub 2} molecule collisions, involving the {sup 2}{sigma}{sub g}{sup +} excited electronic Rydberg state of molecular hydrogen ion H{sub 2}{sup -}, is investigated theoretically. The DEA cross section has been calculated within the local complex potential approximation. The convoluted cross section, which presents a peak located at the incident energy of about 14 eV, compares favorably with available experimental data.

  4. Pseudopotential calculations for elastic scattering of slow electrons (0--20 eV) from noble gases. II. Krypton

    SciTech Connect

    Plenkiewicz, B.; Plenkiewicz, P.; Houee-Levin, C.; Jay-Gerin, J.

    1988-12-15

    The pseudopotential calculations of Plenkiewicz et al. on electrons colliding with argon are extended to consider the elastic electron-krypton scattering system. Phase shifts, differential, total, and momentum-transfer cross sections are obtained for incident electron energies in the range 0--20 eV. Our results are found to be in very good agreement with available experimental data and other theoretical results.

  5. Two-photon double ionization of H2 at 30 eV using Exterior Complex Scaling

    SciTech Connect

    Morales, Felipe; Martin, Fernando; Horner, Daniel; Rescigno, Thomas N.; McCurdy, C. William

    2009-01-20

    Calculations of fully differential cross sections for two-photon double ionization of the hydrogen molecule with photons of 30 eV are reported. The results have been obtained by using the method of exterior complex scaling, which allows one to construct essentially exact wave functions that describe thedouble continuum on a large, but finite, volume. The calculated cross sections are compared with those previously obtained by Colgan et al., and discrepancies are found for specific molecular orientations and electron ejection directions.

  6. Effects of excess oxygen on the 4.5-6.3 eV absorption spectra of oxygen-rich high purity silica

    NASA Astrophysics Data System (ADS)

    Magruder, R. H.; Robinson, S. J.

    2016-05-01

    Type III silica samples were implanted with O using a multi-energy process that produced a layer of constant concentration to within ±5% beginning ∼80 nm from the surface and extending to ∼640 nm below the surfaces of the samples. The concentrations of excess oxygen in the layer ranged from 0.035 to ∼2.1at.%. In these samples we show that E‧ centers and NBOHCs, as well as the normal cadre of ODC (II) centers, were suppressed, and the optical absorption from 4.7 to 6.4 eV was primarily due to oxygen excess defects. Using Gaussian fitting techniques to examine the optical difference spectra, we have been able to identify four defect centers that are related to excess oxygen defect bands at 4.76 eV, 5.42 eV, 5.75 eV and 6.25 eV.

  7. Optical constants of magnetron sputtered boron carbide thin films from photoabsorption data in the range 30 to 770 eV

    SciTech Connect

    Soufli, R; Aquila, A L; Salmassi, F; Fernandez-Perea, M; Gullikson, E M

    2008-05-21

    This work discusses the experimental determination of the optical constants (refractive index) of DC-magnetron-sputtered boron carbide films in the 30-770 eV photon energy range. Transmittance measurements of three boron carbide films with thicknesses of 54.2, 79.0 and 112.5 nm were performed for this purpose. These are the first published experimental data for the refractive index of boron carbide films in the photon energy range above 160 eV, and for the near-edge x-ray absorption fine structure (NEXAFS) regions around the boron K (188 eV), carbon K (284.2 eV) and oxygen K (543.1 eV) absorption edges. The density, composition, surface chemistry and morphology of the films in this manuscript were also investigated using Rutherford Backscattering (RBS), X-ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), and extreme ultraviolet (EUV) reflectance measurements.

  8. Absolute total electron scattering cross sections for N/sub 2/ between 0. 5 and 50 eV

    SciTech Connect

    Kennerly, R.E.

    1980-06-01

    Absolute total electron scattering cross sections for N/sub 2/ from 0.5 to 50 eV have been measured with an estimated uncertainty of +- 3% using a transmission time-of-flight method previously described. The results are compared to previous experimental results and to recent calculations. The positions of the /sup 2/Pi/sub g/ resonance peaks were determined with much greater accuracy ( +- 15 meV) than in previous transmission measurements. The structure reported by Golden (1966) below the /sup 2/Pi/sub g/ resonance was clearly not present, indicating that, if real, these features are not a property of the N/sub 2/ ground vibronic state. The shape resonance predicted at 11 eV by Dill and Dehmer (1977) was not seen, perhaps because it was too weakly manifested in the total cross section. A weak broad band centered at 25 eV may be interpreted as being due to a sigma/sub u/ shape resonance as predicted by Dehmer, Siegel, Welch, and Dill.

  9. Particles of primary cosmic radiation generating extensive air showers of energy above 1020 eV in the atmosphere

    NASA Astrophysics Data System (ADS)

    Dedenko, L. G.; Glushkov, A. V.; Knurenko, S. P.; Makarov, I. T.; Pravdin, M. I.; Podgrudkov, D. A.; Sleptzov, I. E.; Roganova, T. M.; Fedorova, G. F.; Fedunin, E. Yu.

    2010-12-01

    In order to construct the energy spectrum on the basis of data from the Yakutsk array, a method similar to that employed at the AGASA array is applied in addition to the standard approach based on experimental procedures. Moreover, a new, original, method underlying the calculation of the spectrum in the region of energies above 1020 eV is used to estimate energies. In order to compare data obtained at different arrays, it is proposed to harness the universal spectrum based on HiRes data. Within the QGSJET2 model, it is shown that a shower of energy 2 × 1020 eV was observed at the Yakutsk array. In the same energy region (above 2 × 1020 eV), the AGASA array recorded four showers, while the Fly's Eye array and Pierre Auger Observatory (PAO) recorded one shower each. These data do not confirm the conclusion that the flux of primary-cosmic-ray particles decreases because of the Greisen-Zatsepin-Kuzmin effect.

  10. Electron Processing at 50 eV of Terphenylthiol Self-Assembled Monolayers: Contributions of Primary and Secondary Electrons.

    PubMed

    Houplin, Justine; Dablemont, Céline; Sala, Leo; Lafosse, Anne; Amiaud, Lionel

    2015-12-22

    Aromatic self-assembled monolayers (SAMs) can serve as platforms for development of supramolecular assemblies driven by surface templates. For many applications, electron processing is used to locally reinforce the layer. To achieve better control of the irradiation step, chemical transformations induced by electron impact at 50 eV of terphenylthiol SAMs are studied, with these SAMs serving as model aromatic SAMs. High-resolution electron energy loss spectroscopy (HREELS) and electron-stimulated desorption (ESD) of neutral fragment measurements are combined to investigate electron-induced chemical transformation of the layer. The decrease of the CH stretching HREELS signature is mainly attributed to dehydrogenation, without a noticeable hybridization change of the hydrogenated carbon centers. Its evolution as a function of the irradiation dose gives an estimate of the effective hydrogen content loss cross-section, σ = 2.7-4.7 × 10(-17) cm(2). Electron impact ionization is the major primary mechanism involved, with the impact electronic excitation contributing only marginally. Therefore, special attention is given to the contribution of the low-energy secondary electrons to the induced chemistry. The effective cross-section related to dissociative secondary electron attachment at 6 eV is estimated to be 1 order of magnitude smaller. The 1 eV electrons do not induce significant chemical modification for a 2.5 mC cm(-2) dose, excluding their contribution. PMID:26606369

  11. Unresolved clinical aspects and safety hazards of blood derived- EV/MV in stored blood components: From personal memory lanes to newer perspectives on the roles of EV/MV in various biological phenomena.

    PubMed

    Seghatchian, Jerard; Amiral, Jean

    2016-08-01

    Blood cells generate heterogeneous populations of vesicles that are delivered, as small-specialized packages of highly active cell fragments in blood circulation, having almost similar functional activities, as the mother cells. These so called extracellular vesicles are the essential part of an energy-dependent natural apoptotic process; hence their beneficial and harmful biological functions cannot be ignored. Evidence is accumulating, that cellular derived vesicles, originate from all viable cells including: megakaryocytes, platelets, red blood cells, white blood cells and endothelial cells, the highest in proportions from platelets. Shedding can also be triggered by pathological activation of inflammatory processes and activation of coagulation or complement pathways, or even by shear stress in the circulation. Structurally, so called MV/EV appear to be, sometimes inside-out and sometimes outside-in cell fragments having a bilayered phospholipid structure exposing coagulant-active phosphatidylserine, expressing various membrane receptors, and they serve as cell-to-cell shuttles for bioactive molecules such as lipids, growth factors, microRNAs, and mitochondria. Ex vivo processing of blood into its components, embodying centrifugation, processing by various apheresis procedures, leukoreduction, pathogen reduction, and finally storage in different media and different types of blood bags, also have major impacts on the generation and retention of MV content. These artificially generated small, but highly liable packages, together with the original pool of MVs collected from the donor, do exhibit differing biological activities, and are not inert elements and should be considered as a parameter of blood safety in haemovigilance programmes. Harmonization and consensus in sampling protocols, sample handling, processing, and assessment methods, in particular converting to full automation, are needed to achieve consensual interpretations. This review focuses on some of

  12. Limits on the neutrino mass from cosmology

    SciTech Connect

    Melchiorri, Alessandro; De Bernardis, Francesco; Menegoni, Eloisa

    2010-07-12

    We use measurements of luminosity-dependent galaxy bias at several different redshifts, SDSS at z = 0.05, DEEP2 at z = 1 and LBGs at z = 3.8, combined with WMAP five-year cosmic microwave background anisotropy data and SDSS Red Luminous Galaxy survey three-dimensional clustering power spectrum to put constraints on cosmological parameters. Fitting this combined dataset, we show that the luminosity-dependent bias data that probe the relation between halo bias and halo mass and its redshift evolution are very sensitive to sum of the neutrino masses: in particular we obtain the upper limit of {Sigma}m{sub {nu}<}0.28 eV at the 95% confidence level for a {Lambda}CDM+m{sub {nu}}model, with a {sigma}8 equal to {sigma}8 = 0.759{+-}0.025 (1{sigma}). When we allow the dark energy equation of state parameter w to vary we find w -1.30{+-}0.19 for a general wCDM+m{sub {nu}}model with the 95% confidence level upper limit on the neutrino masses at {Sigma}m{sub {nu}<}0.59 eV. The constraint on the dark energy equation of state further improves to w = -1.125{+-}0.092 when using also ACBAR and supernovae Union data, in addition to above, with a prior on the Hubble constant from the Hubble Space Telescope. Finally, we have investigated the ability of future cosmic shear measurements, like those achievable with the proposed Euclid mission, to constrain differences in the mass of individual neutrino species.

  13. Majorana neutrino masses from neutrinoless double-beta decays and lepton-number-violating meson decays

    NASA Astrophysics Data System (ADS)

    Liu, Jun-Hao; Zhang, Jue; Zhou, Shun

    2016-09-01

    The Schechter-Valle theorem states that a positive observation of neutrinoless double-beta (0 νββ) decays implies a finite Majorana mass term for neutrinos when any unlikely fine-tuning or cancellation is absent. In this note, we reexamine the quantitative impact of the Schechter-Valle theorem, and find that current experimental lower limits on the half-lives of 0 νββ-decaying nuclei have placed a restrictive upper bound on the Majorana neutrino mass | δ mνee | < 7.43 ×10-29 eV radiatively generated at the four-loop level. Furthermore, we generalize this quantitative analysis of 0 νββ decays to that of the lepton-number-violating (LNV) meson decays M- →M‧+ + ℓα- + ℓβ- (for α , β = e or μ). Given the present upper limits on these rare LNV decays, we have derived the loop-induced Majorana neutrino masses | δ mνee | < 9.7 ×10-18 eV, | δ mνeμ | < 1.6 ×10-15 eV and | δ mνμμ | < 1.0 ×10-12 eV from K- →π+ +e- +e-, K- →π+ +e- +μ- and K- →π+ +μ- +μ-, respectively. A partial list of radiative neutrino masses from the LNV decays of D, Ds and B mesons is also given.

  14. Absolute VUV Photoionization Spectra for Hcho, HO{_2}, and H{_2}O{_2} from 10.5-12.0 eV

    NASA Astrophysics Data System (ADS)

    Dodson, Leah G.; Shen, Linhan; Eddingsaas, Nathan C.; Takematsu, Kana; Savee, John D.; Welz, Oliver; Taatjes, Craig A.; Osborn, David L.; Sander, Stanley P.; Okumura, Mitchio

    2013-06-01

    The absolute vacuum ultraviolet (VUV) photoionization spectra of formaldehyde (HCHO), the hydroperoxy radical (HO{_2}) and hydrogen peroxide (H{_2}O{_2}) have been measured. The ability to quantify these species is critical for photoionization mass spectrometry studies of the kinetics of atmospheric and combustion reactions, which require accurate cross sections over a wide range of ionization energies. Experiments were performed at the Advanced Light Source (ALS) synchrotron at the Lawrence Berkeley National Laboratory. HCHO, HO{_2}, and H{_2}O{_2} were generated from the oxidation of methanol which is initiated by pulsed-laser-photolysis of Cl{_2} in a low pressure flow cell. Sampled gas was ionized by tunable VUV radiation from the ALS synchrotron and detected by time-resolved multiplexed photoionization mass spectrometry using the Sandia Multiplexed Chemical Kinetics Reactor. The photoionization spectra were obtained by scanning the photon energy from 10.5 to 12.0 eV. Absolute cross sections were determined relative to methanol from measurements of the depletion of precursors and kinetic modeling of the initial chemistry ({<} 10 ms). The absolute photoionization spectrum of HCHO and the relative photoionization spectra of HO{_2} and H{_2}O{_2} are in good agreement with previous work. D. L. Osborn, P. Zou, H. Johnson, C. C. Hayden, C. A. Taatjes, V. D. Knyazev, S. W. North, D. S. Peterka, M. Ahmed, S. R. Leone. Rev. Sci. Inst. 2008, 79, 104103. G. Cooper, J. E. Anderson, C. E. Brion. Chem. Phys. 1996, 209, 61. M. Litorja, B. J. Ruscic. Electron Spectrosc. Relat. Phenom. 1998, 97, 131.

  15. Constraints on the mass of unstable neutrinos from the supernova

    NASA Astrophysics Data System (ADS)

    Liu, Jiang

    1987-11-01

    The cosmological constraint together with the information obtained from the supernova could be used to give a lower bound on the mass of unstable neutrinos. It is shown that if the only viable channel for the unstable neutrino decay is through three lighter neutrinos, the mass of this particle should be heavier than about 500 eV. I wish to thank Professor Ling-Fong Li and Professor Lincoln Wolfenstein for valuable discussions. This work was supported in part by the US Department of Energy.

  16. 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

  17. Relating lepton mixing angles with lepton mass hierarchy

    NASA Astrophysics Data System (ADS)

    Borah, Debasish

    2016-01-01

    We revisit the possibility of relating lepton mixing angles with lepton mass hierarchies in a model-independent way. Guided by the existence of such relations in the quark sector, we first consider all the mixing angles, both in charged lepton and neutrino sectors to be related to the respective mass ratios. This allows us to calculate the leptonic mixing angles observed in neutrino oscillations as functions of the lightest neutrino mass. We show that for both normal and inverted hierarchical neutrino masses, this scenario does not give rise to correct leptonic mixing angles. We then show that correct leptonic mixing angles can be generated with normal hierarchical neutrino masses if the relation between mixing angle and mass ratio is restricted to 1-2 and 1-3 mixing in both charged lepton and neutrino sectors leaving the 2-3 mixing angles as free parameters. We then restrict the lightest neutrino mass as well as the difference between 2-3 mixing angles in charged lepton and neutrino sectors from the requirement of producing correct leptonic mixing angles. We constrain the lightest neutrino mass to be around 0.002 eV and leptonic Dirac CP phase δCP such that sin2δ CP ˜ (0.35-0.50). We also construct the leptonic mass matrices in terms of 2-3 mixing angles and lightest neutrino mass and briefly comment on the possibility of realizing texture zeros in the neutrino mass matrix.

  18. Dependence of the muon pseudorapidity on the cosmic ray mass composition around the knee

    NASA Astrophysics Data System (ADS)

    Rastegarzadeh, Gohar; Nemati, Mohammad

    2015-11-01

    In order to identify the mass composition of cosmic rays (CRs), we have investigated the mean muon pseudorapidity (<η>) values of muonic component in extensive air showers (EASs). For this purpose we have simulated EASs by CORSIKA 7.4 code for Hydrogen, Oxygen and Iron nucleus. The energy range was selected between 1014 eV and 1016 eV with zenith angle from 0°-18°. We have compared our calculations with KASCADE muon tracking detector (MTD) measurements to obtain results on the primary mass relationship with mean muon pseudorapidity values of EASs muonic component. It is shown that after the knee energies, experimental data tend to the heavy primaries and mass composition becomes heavier. Finally, linear equations between the mass of primary and mean η values for different energies are obtained.

  19. Fine Structure of Near-Surface Solar Wind Depth Profile by SNMS/SEM Imaging

    NASA Astrophysics Data System (ADS)

    Baryshev, S. V.; Zinovev, A. V.; Tripa, C. E.; Pellin, M. J.; Burnett, D. S.; Veryovkin, I. V.

    2012-03-01

    In this work, we report results of Genesis Si coupons investigations conducted by laser post-ionization secondary neutral mass spectrometry (LPI SNMS) based on dual beam depth profiling with low energy normal incidence sputtering (lenisDB).

  20. Constraints on neutrino masses from weak lensing

    SciTech Connect

    Ichiki, Kiyotomo; Takada, Masahiro; Takahashi, Tomo

    2009-01-15

    Weak lensing (WL) distortions of distant galaxy images are sensitive to neutrino masses by probing the suppression effect on clustering strengths of total matter in large-scale structure. We use the latest measurements of WL correlations, the Canada-France-Hawaii Telescope Legacy Survey data, to explore constraints on neutrino masses. We find that, while the WL data alone cannot place a stringent limit on neutrino masses due to parameter degeneracies, the constraint can be significantly improved when combined with other cosmological probes, such as the WMAP 5-year data (WMAP5) and the distance measurements of type-Ia supernovae (SNe) and baryon acoustic oscillations (BAO). The upper bounds on the sum of neutrino masses are , 0.76, and 0.54 eV (95% CL) for WL+WMAP5, WMAP5+SNe+BAO, and WL+WMAP5+SNe+BAO, respectively, assuming a flat {lambda}CDM model with finite-mass neutrinos. In deriving these constraints, our analysis includes the non-Gaussian covariances of the WL correlation functions to properly take into account significant correlations between different angles.

  1. Transition-Edge Sensor Arrays of Microcalorimeters with ^{163} Ho for Direct Neutrino Mass Measurements with HOLMES

    NASA Astrophysics Data System (ADS)

    Orlando, A.; Biasotti, M.; Ceriale, V.; De Gerone, M.; Gatti, F.; Hays-Wehle, J.; Pizzigoni, G.; Schmidt, D.; Swetz, D.; Ullom, J.

    2016-01-01

    The HOLMES experiment will provide an important step forward in direct neutrino mass measurements with a calorimetric approach as an alternative to spectrometry. HOLMES will perform a calorimetric measurement of the energy released in the decay of ^{163} Ho and will deploy a large array of transition-edge sensor microcalorimeters with implanted ^{163} Ho nuclei. The resulting mass sensitivity could be as low as 0.4 eV, and it will also establish the potential of this approach to extend the sensitivity down to 0.1 eV and lower.

  2. A Precision Measurement of the W Boson Mass with 1 Inverse Femtobarn of DZero Run IIa Data

    SciTech Connect

    Osta, Jyotsna

    2009-12-01

    This thesis is a detailed presentation of a precision measurement of the mass of the W boson. It has been obtained by analyzing W → ev decays. The data used for this analysis was collected from 2002 to 2006 with the D0 detector, during Run IIa of the Fermilab Tevatron collider. It corresponds to a total integrated luminosity of 1 fb-1. With a sample of 499,830 W → ev candidate events, we obtain a mass measurement of MW = 80.401 ± 0.043 GeV. This is the most precise measurement from a single experiment to date.

  3. Transition-Edge Sensor Arrays of Microcalorimeters with ^{163}Ho for Direct Neutrino Mass Measurements with HOLMES

    NASA Astrophysics Data System (ADS)

    Orlando, A.; Biasotti, M.; Ceriale, V.; De Gerone, M.; Gatti, F.; Hays-Wehle, J.; Pizzigoni, G.; Schmidt, D.; Swetz, D.; Ullom, J.

    2016-08-01

    The HOLMES experiment will provide an important step forward in direct neutrino mass measurements with a calorimetric approach as an alternative to spectrometry. HOLMES will perform a calorimetric measurement of the energy released in the decay of ^{163}Ho and will deploy a large array of transition-edge sensor microcalorimeters with implanted ^{163}Ho nuclei. The resulting mass sensitivity could be as low as 0.4 eV, and it will also establish the potential of this approach to extend the sensitivity down to 0.1 eV and lower.

  4. Mass transport properties of Pu/DT mixtures from orbital free molecular dynamics simulations

    SciTech Connect

    Kress, Joel David; Ticknor, Christopher; Collins, Lee A.

    2015-09-16

    Mass transport properties (shear viscosity and diffusion coefficients) for Pu/DT mixtures were calculated with Orbital Free Molecular Dynamics (OFMD). The results were fitted to simple functions of mass density (for ρ=10.4 to 62.4 g/cm3) and temperature (for T=100 up to 3,000 eV) for Pu/DT mixtures consisting of 100/0, 25/75, 50/50, and 75/25 by number.

  5. Effects of the dual TP receptor antagonist and thromboxane synthase inhibitor EV-077 on human endothelial and vascular smooth muscle cells

    SciTech Connect

    Petri, Marcelo H.; Tellier, Céline; Michiels, Carine; Ellertsen, Ingvill; Dogné, Jean-Michel; Bäck, Magnus

    2013-11-15

    Highlights: •EV-077 reduced TNF-α induced inflammation in endothelial cells. •The thromboxane mimetic U69915 enhanced vascular smooth muscle cell proliferation. •EV-077 inhibited smooth muscle cell proliferation. -- Abstract: The prothrombotic mediator thromboxane A{sub 2} is derived from arachidonic acid metabolism through the cyclooxygenase and thromboxane synthase pathways, and transduces its effect through the thromboxane prostanoid (TP) receptor. The aim of this study was to determine the effect of the TP receptor antagonist and thromboxane synthase inhibitor EV-077 on inflammatory markers in human umbilical vein endothelial cells and on human coronary artery smooth muscle cell proliferation. To this end, mRNA levels of different proinflammatory mediators were studied by real time quantitative PCR, supernatants were analyzed by enzyme immune assay, and cell proliferation was assessed using WST-1. EV-077 significantly decreased mRNA levels of ICAM-1 and PTX3 after TNFα incubation, whereas concentrations of 6-keto PGF1α in supernatants of endothelial cells incubated with TNFα were significantly increased after EV-077 treatment. Although U46619 did not alter coronary artery smooth muscle cell proliferation, this thromboxane mimetic enhanced the proliferation induced by serum, insulin and growth factors, which was significantly inhibited by EV-077. In conclusion, EV-077 inhibited TNFα-induced endothelial inflammation and reduced the enhancement of smooth muscle cell proliferation induced by a thromboxane mimetic, supporting that the thromboxane pathway may be associated with early atherosclerosis in terms of endothelial dysfunction and vascular hypertrophy.

  6. A new EV71 VP3 epitope in norovirus P particle vector displays neutralizing activity and protection in vivo in mice.

    PubMed

    Jiang, Liping; Fan, Rongjun; Sun, Shiyang; Fan, Peihu; Su, Weiheng; Zhou, Yan; Gao, Feng; Xu, Fei; Kong, Wei; Jiang, Chunlai

    2015-11-27

    Enterovirus 71 (EV71) and Coxsackievirus A16 (CVA16), as the main agents causing hand, foot and mouth disease (HFMD), have become a serious public health concern in the Asia-Pacific region. Recently, various neutralizing B cell epitopes of EV71 were identified as targets for promising vaccine candidates. Structural studies of Picornaviridae indicated that potent immunodominant epitopes typically lie in the hypervariable loop of capsid surfaces. However, cross-neutralizing antibodies and cross-protection between EV71 and CVA16 have not been observed. Therefore, we speculated that divergent sequences of the two viruses are key epitopes for inducing protective neutralizing responses. In this study, we selected 10 divergent epitope candidates based on alignment of the EV71 and CVA16 P1 amino acid sequences using the Multalin interface page, and these epitopes are conserved among all subgenotypes of EV71. Simultaneously, by utilizing the norovirus P particle as a novel vaccine delivery carrier, we identified the 71-6 epitope (amino acid 176-190 of VP3) as a conformational neutralizing epitope against EV71 in an in vitro micro-neutralization assay as well as an in vivo protection assay in mice. Altogether, these results indicated that the incorporation of the 71-6 epitope into the norovirus P domain can provide a promising candidate for an effective synthetic peptide-based vaccine against EV71. PMID:26529072

  7. Liquid cooled plate heat exchanger for battery cooling of an electric vehicle (EV)

    NASA Astrophysics Data System (ADS)

    Rahman, M. M.; Rahman, H. Y.; Mahlia, T. M. I.; Sheng, J. L. Y.

    2016-03-01

    A liquid cooled plate heat exchanger was designed to improve the battery life of an electric vehicle which suffers from premature aging or degradation due to the heat generation during discharging and charging period. Computational fluid dynamics (CFD) was used as a tool to analyse the temperature distribution when a constant surface heat flux was set at the bottom surface of the battery. Several initial and boundary conditions were set based on the past studies on the plate heat exchanger in the simulation software. The design of the plate heat exchanger was based on the Nissan Leaf battery pack to analyse the temperature patterns. Water at different mass flow rates was used as heat transfer fluid. The analysis revealed the designed plate heat exchanger could maintain the surface temperature within the range of 20 to 40°C which is within the safe operating temperature of the battery.

  8. High intensity 5 eV O-atom exposure facility for material degradation studies

    NASA Technical Reports Server (NTRS)

    Cross, J. B.; Spangler, L. H.; Hoffbauer, M. A.; Archuleta, F. A.; Leger, Lubert; Visentine, James; Hunton, Don E.; Cross, J. B.

    1986-01-01

    An atomic oxygen exposure facility was developed for studies of material degradation. The goal of these studies is to provide design criteria and information for the manufacture of long life (20 to 30 years) construction materials for use in low Earth orbit. The studies that are being undertaken will provide: (1) absolute reaction cross sections for the engineering design problems, (2) formulations of reaction mechanisms for use in the selection of suitable existing materials and the design of new more resistant ones, and (3) the calibration of flight hardware (mass spectrometers, etc.) in order to directly relate experiments performed in low Earth orbit to ground based investigations. The facility consists of a CW laser sustained discharge source of O-atoms, an atomic beam formation and diagnostics system, a spinning rotor viscometer, and provision for using the system for calibration of actual flight instruments.

  9. Energy Spectra and Mass Composition of Cosmic Rays in the Fractal-Like Galactic Medium

    NASA Astrophysics Data System (ADS)

    Lagutin, A. A.; Tyumentsev, A. G.; Yushkov, A. V.

    We consider the problem of the cosmic ray spectrum formation assuming that cosmic rays are produced by galactic sources. The fractional diffusion equation proposed in our recent papers is used to describe the cosmic rays propagation in interstellar medium. We show that in the framework of this approach it is possible to explain the locally observed basic features of the cosmic rays in the energy region 1010 ÷ 1020 eV: difference between spectral exponents of protons and other nuclei, mass composition variation, "knee" problem, flattening of the primary spectrum for E ≥ 1018 ÷ 1019 eV.

  10. Neff in low-scale seesaw models versus the lightest neutrino mass

    NASA Astrophysics Data System (ADS)

    Hernández, P.; Kekic, M.; Lopez-Pavon, J.

    2014-09-01

    We evaluate the contribution to Neff of the extra sterile states in low-scale type I seesaw models (with three extra sterile states). We explore the full parameter space and find that at least two of the heavy states always reach thermalization in the early Universe, while the third one might not thermalize provided the lightest neutrino mass is below O(10-3 eV). Constraints from cosmology therefore severely restrict the spectra of heavy states in the range 1 eV-100 MeV. The implications for neutrinoless double beta decay are also discussed.

  11. Planetary In Situ Sample Analysis with Tandem Two-Step Laser Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Brinckerhoff, W. B.; Getty, S. A.; Cornish, T. J.; Ecelberger, S. A.; Li, X.; Merrill Floyd, M. A.; Arevalo, R.; Elsila, J.; Callahan, M. P.

    2012-12-01

    -) and organic moieties. Second, by focusing a separate "post-ionization" laser pulse just above the sample surface, we can achieve two-step laser mass spectrometry, or L2MS, in the same highly-miniaturized TOF-MS. L2MS enables selective analysis of aromatic organics even in the presence of a complex mineral matrix. Finally, by introducing an ion optical gate in the flight path, we are able to take advantage of the broad focusing capabilities of the "curved field" reflectron at the core of the TOF-MS to achieve pseudo-tandem structural analysis of selected organics. The high-speed gate is used to admit only the molecular ion/s of interest into the reflectron. Diagnostic fragments of the ion/s obtained through metastable decay or active collision-induced dissociation (CID) remain in focus despite having widely variable velocities and masses. As such even molecular isomers with differing fragmentation pathways may be distinguished through a series of pseudo-tandem mass spectra that could be obtained in an automatic process during a mission. The "real-world" benefits of these enhancements are being fully characterized using a set of synthetic and natural standard samples as well as several planetary analogs and meteorites.

  12. A Method for Compensating Customer Voltage Drops due to Nighttime Simultaneous Charging of EVs Utilizing Reactive Power Injection from Battery Chargers

    NASA Astrophysics Data System (ADS)

    Noda, Taku; Kabasawa, Yuichiro; Fukushima, Kentaro; Nemoto, Koshichi; Uemura, Satoshi

    When we consider the global warming, the reduction of CO2 emission is one of the most important problems which require urgent solutions. One option is to integrate low-CO2-emission generators to the grid as much as possible. Another option is to replace inefficient vehicles based on internal-combustion engines with electric ones (EVs). Due to the latter, we can easily estimate that most consumers will charge EVs' batteries at nighttime. Thus, excessive voltage drops due to the nighttime simultaneous charging are supposed to be a possible future problem. This paper proposes a method for compensating the voltage drops by injecting reactive power from EV battery chargers.

  13. Observation of >400-eV Precursor Plasmas from Low-Wire-Number Copper Arrays at the 1-MA Zebra Facility

    SciTech Connect

    Coverdale, C. A.; Ampleford, D. J.; Jones, B.; Safronova, A. S.; Kantsyrev, V. L.; Ouart, N. D.; Esaulov, A. A.; Williamson, K. M.; Osborne, G. C.; Shrestha, I.; Deeney, C.

    2009-04-17

    Experiments with cylindrical copper wire arrays at the 1-MA Zebra facility show that high temperatures exist in the precursor plasmas formed when ablated wire array material accretes on the axis prior to the stagnation of a z pinch. In these experiments, the precursor radiated approximately 20% of the >1000 eV x-ray output, and time-resolved spectra show substantial emission from Cu L-shell lines. Modeling of the spectra shows an increase in temperature as the precursor forms, up to {approx}450 eV, after which the temperature decreases to {approx}220-320 eV until the main implosion.

  14. Measurement of the electron antineutrino mass in tritium beta decay in the Troitsk nu-mass experiment

    SciTech Connect

    Aseev, V. N.; Belesev, A. I.; Berlev, A. I.; Geraskin, E. V.; Golubev, A. A.; Lihovid, N. A.; Lobashev, V. M.; Nozik, A. A.; Pantuev, V. S.; Parfenov, V. I.; Skasyrskaya, A. K.; Tkachov, F. V.; Zadorozhny, S. V.

    2012-04-15

    The results obtained in the Troitsk nu-mass experiment by measuring the electron-antineutrino mass in tritium beta decay are presented. The facility used consists of a gaseous windowless tritium source and an electrostatic electron spectrometer involving an adiabatic magnetic collimation. Runs in which measurement conditions were reliably established were thoroughly selected in analyzing data obtained from 1994 to 2004. All known systematic effects were taken into account. For the square of the electron-antineutrino mass, the treatment of measured spectra yielded the following result: m{sub {nu}}{sup 2} = -0.67 {+-} 1.89{sub stat.} {+-} 1.68{sub syst.} eV{sup 2}. The use of the Bayesian method and the Feldman-Cousins unified approach made it possible to obtain the following upper limits on the mass: m{sub {nu}} < 2.12 eV (at a 95% C.L.; Bayesian method) and m{sub {nu}} < 2.05 eV (at a 95% C.L., Feldman-Cousins method). At the same time, an estimation of the sensitivity limit without allowance for negative values of the square of the mass leads to m{sub {nu}} < 2.2 eV (at a 95% C.L.). Measured spectra were analyzed for the possible existence of an additional structure (step) in the electron spectrum near the boundary energy. The conclusion drawn from this analysis was that, within the existing statistical errors, there are no reasons for introducing such a feature.

  15. Searching for a correlation between cosmic-ray sources above 10{sup 19} eV and large scale structure

    SciTech Connect

    Kashti, Tamar; Waxman, Eli E-mail: eli.waxman@weizmann.ac.il

    2008-05-15

    We study the anisotropy signature which is expected if the sources of ultrahigh energy, >10{sup 19} eV, cosmic rays (UHECRs) are extra-galactic and trace the large scale distribution of luminous matter. Using the PSCz galaxy catalog as a tracer of the large scale structure (LSS), we derive the expected all sky angular distribution of the UHECR intensity. We define a statistic that measures the correlation between the predicted and observed UHECR arrival direction distributions, and show that it is more sensitive to the expected anisotropy signature than the power spectrum and the two-point correlation function. The distribution of the correlation statistic is not sensitive to the unknown redshift evolution of UHECR source density and to the unknown strength and structure of inter-galactic magnetic fields. We show, using this statistic, that recently published >5.7 Multiplication-Sign 10{sup 19} eV Auger data are inconsistent with isotropy at Asymptotically-Equal-To 98% CL, and consistent with a source distribution that traces LSS, with some preference for a source distribution that is biased with respect to the galaxy distribution. The anisotropy signature should be detectable also at lower energy, >4 Multiplication-Sign 10{sup 19} eV. A few-fold increase of the Auger exposure is likely to increase the significance to >99% CL, but not to>99.9% CL (unless the UHECR source density is comparable to or larger than that of galaxies). In order to distinguish between different bias models, the systematic uncertainty in the absolute energy calibration of the experiments should be reduced to well below the current Asymptotically-Equal-To 25%.

  16. A unified structural/terminological interoperability framework based on LexEVS: application to TRANSFoRm

    PubMed Central

    Ethier, Jean-François; Dameron, Olivier; Curcin, Vasa; McGilchrist, Mark M; Verheij, Robert A; Arvanitis, Theodoros N; Taweel, Adel; Delaney, Brendan C; Burgun, Anita

    2013-01-01

    Objective Biomedical research increasingly relies on the integration of information from multiple heterogeneous data sources. Despite the fact that structural and terminological aspects of interoperability are interdependent and rely on a common set of requirements, current efforts typically address them in isolation. We propose a unified ontology-based knowledge framework to facilitate interoperability between heterogeneous sources, and investigate if using the LexEVS terminology server is a viable implementation method. Materials and methods We developed a framework based on an ontology, the general information model (GIM), to unify structural models and terminologies, together with relevant mapping sets. This allowed a uniform access to these resources within LexEVS to facilitate interoperability by various components and data sources from implementing architectures. Results Our unified framework has been tested in the context of the EU Framework Program 7 TRANSFoRm project, where it was used to achieve data integration in a retrospective diabetes cohort study. The GIM was successfully instantiated in TRANSFoRm as the clinical data integration model, and necessary mappings were created to support effective information retrieval for software tools in the project. Conclusions We present a novel, unifying approach to address interoperability challenges in heterogeneous data sources, by representing structural and semantic models in one framework. Systems using this architecture can rely solely on the GIM that abstracts over both the structure and coding. Information models, terminologies and mappings are all stored in LexEVS and can be accessed in a uniform manner (implementing the HL7 CTS2 service functional model). The system is flexible and should reduce the effort needed from data sources personnel for implementing and managing the integration. PMID:23571850

  17. Development of a Quantum Dot, 0.6 eV InGaAs Thermophotovoltaic (TPV) Converter

    NASA Technical Reports Server (NTRS)

    Forbes, David; Sinharoy, Samar; Raffalle, Ryne; Weizer, Victor; Homann, Natalie; Valko, Thomas; Bartos,Nichole; Scheiman, David; Bailey, Sheila

    2007-01-01

    Thermophotovoltaic (TPV) power conversion has to date demonstrated conversion efficiencies exceeding 20% when coupled to a heat source. Current III-V semiconductor TPV technology makes use of planar devices with bandgaps tailored to the heat source. The efficiency can be improved further by increasing the collection efficiency through the incorporation of InAs quantum dots. The use of these dots can provide sub-gap absorption and thus improve the cell short circuit current without the normal increase in dark current associated with lowering the bandgap. We have developed self-assembled InAs quantum dots using the Stranski-Krastanov growth mode on 0.74 eV In0.53GaAs lattice-matched to InP and also on lattice-mismatched 0.6 eV In0.69GaAs grown on InP through the use of a compositionally graded InPAsx buffer structure, by metalorganic vapor phase epitaxy (MOVPE). Atomic force microscopy (AFM) measurements showed that the most reproducible dot pattern was obtained with 5 monolayers of InAs grown at 450 C. The lattice mismatch between InAs and In0.69GaAs is only 2.1%, compared to 3.2% between InAs and In0.53GaAs. The smaller mismatch results in lower strain, making dot formation somewhat more complicated, resulting in quantum dashes, rather than well defined quantum dots in the lattice-mismatched case. We have fabricated 0.6 eV InGaAs planer TPV cells with and without the quantum dashes

  18. Mass-dependent channel electron multiplier operation. [for ion detection

    NASA Technical Reports Server (NTRS)

    Fields, S. A.; Burch, J. L.; Oran, W. A.

    1977-01-01

    The absolute counting efficiency and pulse height distributions of a continuous-channel electron multiplier used in the detection of hydrogen, argon and xenon ions are assessed. The assessment technique, which involves the post-acceleration of 8-eV ion beams to energies from 100 to 4000 eV, provides information on counting efficiency versus post-acceleration voltage characteristics over a wide range of ion mass. The charge pulse height distributions for H2 (+), A (+) and Xe (+) were measured by operating the experimental apparatus in a marginally gain-saturated mode. It was found that gain saturation occurs at lower channel multiplier operating voltages for light ions such as H2 (+) than for the heavier ions A (+) and Xe (+), suggesting that the technique may be used to discriminate between these two classes of ions in electrostatic analyzers.

  19. Enhanced High Harmonic Generation from Multiply Ionized Argon above 500 eV through Laser Pulse Self-Compression

    SciTech Connect

    Arpin, P.; Popmintchev, T.; Kapteyn, H. C.; Murnane, M. M.; Wagner, N. L.; Cohen, O.

    2009-10-02

    By combining laser pulse self-compression and high harmonic generation within a single waveguide, we demonstrate high harmonic emission from multiply charged ions for the first time. This approach enhances the laser intensity and counteracts ionization-induced defocusing, extending the cutoff photon energy in argon above 500 eV for the first time, with higher spectral intensity and cutoff energy than He for the same input laser parameters. This Letter demonstrates a pathway for extending high harmonic emission to very high photon energies using large, multiply charged, ions with high ionization potentials.

  20. Surface interaction mechanisms of 5eV atomic oxygen: Data analysis from the UAH experiment on STS-8

    NASA Technical Reports Server (NTRS)

    Gregory, J. C.

    1987-01-01

    The University of Alabama in Huntsville (UAH) experiment which flew on the STS-8 mission had several objectives which were mostly of a speculative nature since so little was known of the processes of interest. The experiment provided original, if limited, data on: (1) oxidation of metal surfaces, (2) reaction rates of atomic oxygen with carbon and other surfaces and the dependence of these rates on temperature, and (3) the angular distribution of 5eV atoms scattered off a solid surface. Provided is a review of the results, with reference given to fuller published accounts where these are available.