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Sample records for absolute upper limit

  1. Upper Limit of Weights in TAI Computation

    NASA Technical Reports Server (NTRS)

    Thomas, Claudine; Azoubib, Jacques

    1996-01-01

    The international reference time scale International Atomic Time (TAI) computed by the Bureau International des Poids et Mesures (BIPM) relies on a weighted average of data from a large number of atomic clocks. In it, the weight attributed to a given clock depends on its long-term stability. In this paper the TAI algorithm is used as the basis for a discussion of how to implement an upper limit of weight for clocks contributing to the ensemble time. This problem is approached through the comparison of two different techniques. In one case, a maximum relative weight is fixed: no individual clock can contribute more than a given fraction to the resulting time scale. The weight of each clock is then adjusted according to the qualities of the whole set of contributing elements. In the other case, a parameter characteristic of frequency stability is chosen: no individual clock can appear more stable than the stated limit. This is equivalent to choosing an absolute limit of weight and attributing this to to the most stable clocks independently of the other elements of the ensemble. The first technique is more robust than the second and automatically optimizes the stability of the resulting time scale, but leads to a more complicated computatio. The second technique has been used in the TAI algorithm since the very beginning. Careful analysis of tests on real clock data shows that improvement of the stability of the time scale requires revision from time to time of the fixed value chosen for the upper limit of absolute weight. In particular, we present results which confirm the decision of the CCDS Working Group on TAI to increase the absolute upper limit by a factor of 2.5. We also show that the use of an upper relative contribution further helps to improve the stability and may be a useful step towards better use of the massive ensemble of HP 507IA clocks now contributing to TAI.

  2. Absolute limit on rotation of gravitationally bound stars

    NASA Astrophysics Data System (ADS)

    Glendenning, N. K.

    1994-03-01

    The authors seek an absolute limit on the rotational period for a neutron star as a function of its mass, based on the minimal constraints imposed by Einstein's theory of relativity, Le Chatelier's principle, causality, and a low-density equation of state, uncertainties which can be evaluated as to their effect on the result. This establishes a limiting curve in the mass-period plane below which no pulsar that is a neutron star can lie. For example, the minimum possible Kepler period, which is an absolute limit on rotation below which mass-shedding would occur, is 0.33 ms for a M = 1.442 solar mass neutron star (the mass of PSR1913+16). If the limit were found to be broken by any pulsar, it would signal that the confined hadronic phase of ordinary nucleons and nuclei is only metastable.

  3. Absolute limit on rotation of gravitationally bound stars

    SciTech Connect

    Glendenning, N.K.

    1994-03-01

    The authors seek an absolute limit on the rotational period for a neutron star as a function of its mass, based on the minimal constraints imposed by Einstein`s theory of relativity, Le Chatelier`s principle, causality and a low-density equation of state, uncertainties which can be evaluated as to their effect on the result. This establishes a limiting curve in the mass-period plane below which no pulsar that is a neutron star can lie. For example, the minimum possible Kepler period, which is an absolute limit on rotation below which mass-shedding would occur, is 0.33 ms for a M = 1.442 M{circle_dot} neutron star (the mass of PSR1913+16). If the limit were found to be broken by any pulsar, it would signal that the confined hadronic phase of ordinary nucleons and nuclei is only metastable, an extraordinary conclusion.

  4. ON COMPUTING UPPER LIMITS TO SOURCE INTENSITIES

    SciTech Connect

    Kashyap, Vinay L.; Siemiginowska, Aneta; Van Dyk, David A.; Xu Jin; Connors, Alanna; Freeman, Peter E.; Zezas, Andreas E-mail: asiemiginowska@cfa.harvard.ed E-mail: jinx@ics.uci.ed E-mail: pfreeman@cmu.ed

    2010-08-10

    A common problem in astrophysics is determining how bright a source could be and still not be detected in an observation. Despite the simplicity with which the problem can be stated, the solution involves complicated statistical issues that require careful analysis. In contrast to the more familiar confidence bound, this concept has never been formally analyzed, leading to a great variety of often ad hoc solutions. Here we formulate and describe the problem in a self-consistent manner. Detection significance is usually defined by the acceptable proportion of false positives (background fluctuations that are claimed as detections, or Type I error), and we invoke the complementary concept of false negatives (real sources that go undetected, or Type II error), based on the statistical power of a test, to compute an upper limit to the detectable source intensity. To determine the minimum intensity that a source must have for it to be detected, we first define a detection threshold and then compute the probabilities of detecting sources of various intensities at the given threshold. The intensity that corresponds to the specified Type II error probability defines that minimum intensity and is identified as the upper limit. Thus, an upper limit is a characteristic of the detection procedure rather than the strength of any particular source. It should not be confused with confidence intervals or other estimates of source intensity. This is particularly important given the large number of catalogs that are being generated from increasingly sensitive surveys. We discuss, with examples, the differences between these upper limits and confidence bounds. Both measures are useful quantities that should be reported in order to extract the most science from catalogs, though they answer different statistical questions: an upper bound describes an inference range on the source intensity, while an upper limit calibrates the detection process. We provide a recipe for computing upper

  5. Upper Limit for Regional Sea Level Projections

    NASA Astrophysics Data System (ADS)

    Jevrejeva, Svetlana; Jackson, Luke; Riva, Riccardo; Grinsted, Aslak; Moore, John

    2016-04-01

    With more than 150 million people living within 1 m of high tide future sea level rise is one of the most damaging aspects of warming climate. The latest Intergovernmental Panel on Climate Change report (AR5 IPCC) noted that a 0.5 m rise in mean sea level will result in a dramatic increase the frequency of high water extremes - by an order of magnitude, or more in some regions. Thus the flood threat to the rapidly growing urban populations and associated infrastructure in coastal areas are major concerns for society. Hence, impact assessment, risk management, adaptation strategy and long-term decision making in coastal areas depend on projections of mean sea level and crucially its low probability, high impact, upper range. With probabilistic approach we produce regional sea level projections taking into account large uncertainties associated with Greenland and Antarctica ice sheets contribution. We calculate the upper limit (as 95%) for regional sea level projections by 2100 with RCP8.5 scenario, suggesting that for the most coastlines upper limit will exceed the global upper limit of 1.8 m.

  6. HESS upper limits for Kepler's supernova remnant

    NASA Astrophysics Data System (ADS)

    Aharonian, F.; Akhperjanian, A. G.; Barres de Almeida, U.; Bazer-Bachi, A. R.; Behera, B.; Beilicke, M.; Benbow, W.; Berge, D.; Bernlöhr, K.; Boisson, C.; Bolz, O.; Borrel, V.; Braun, I.; Brion, E.; Brucker, J.; Bühler, R.; Bulik, T.; Büsching, I.; Boutelier, T.; Carrigan, S.; Chadwick, P. M.; Chounet, L.-M.; Clapson, A. C.; Coignet, G.; Cornils, R.; Costamante, L.; Dalton, M.; Degrange, B.; Dickinson, H. J.; Djannati-Ataï, A.; Domainko, W.; O'C. Drury, L.; Dubois, F.; Dubus, G.; Dyks, J.; Egberts, K.; Emmanoulopoulos, D.; Espigat, P.; Farnier, C.; Feinstein, F.; Fiasson, A.; Förster, A.; Fontaine, G.; Füßling, M.; Gallant, Y. A.; Giebels, B.; Glicenstein, J. F.; Glück, B.; Goret, P.; Hadjichristidis, C.; Hauser, D.; Hauser, M.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hinton, J. A.; Hoffmann, A.; Hofmann, W.; Holleran, M.; Hoppe, S.; Horns, D.; Jacholkowska, A.; de Jager, O. C.; Jung, I.; Katarzyński, K.; Kendziorra, E.; Kerschhaggl, M.; Khélifi, B.; Keogh, D.; Komin, Nu.; Kosack, K.; Lamanna, G.; Latham, I. J.; Lemoine-Goumard, M.; Lenain, J.-P.; Lohse, T.; Martin, J. M.; Martineau-Huynh, O.; Marcowith, A.; Masterson, C.; Maurin, D.; McComb, T. J. L.; Moderski, R.; Moulin, E.; Naumann-Godo, M.; de Naurois, M.; Nedbal, D.; Nekrassov, D.; Nolan, S. J.; Ohm, S.; Olive, J.-P.; de Oña Wilhelmi, E.; Orford, K. J.; Osborne, J. L.; Ostrowski, M.; Panter, M.; Pedaletti, G.; Pelletier, G.; Petrucci, P.-O.; Pita, S.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raubenheimer, B. C.; Raue, M.; Rayner, S. M.; Renaud, M.; Ripken, J.; Rob, L.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Ruppel, J.; Sahakian, V.; Santangelo, A.; Schlickeiser, R.; Schöck, F. M.; Schröder, R.; Schwanke, U.; Schwarzburg, S.; Schwemmer, S.; Shalchi, A.; Sol, H.; Spangler, D.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Superina, G.; Tam, P. H.; Tavernet, J.-P.; Terrier, R.; van Eldik, C.; Vasileiadis, G.; Venter, C.; Vialle, J. P.; Vincent, P.; Vivier, M.; Völk, H. J.; Volpe, F.; Wagner, S. J.; Ward, M.; Zdziarski, A. A.; Zech, A.

    2008-09-01

    Aims: Observations of Kepler's supernova remnant (G4.5+6.8) with the HESS telescope array in 2004 and 2005 with a total live time of 13 h are presented. Methods: Stereoscopic imaging of Cherenkov radiation from extensive air showers is used to reconstruct the energy and direction of the incident gamma rays. Results: No evidence for a very high energy (VHE: >100 GeV) gamma-ray signal from the direction of the remnant is found. An upper limit (99% confidence level) on the energy flux in the range 230 GeV{-}12.8 TeV of 8.6 × 10-13 erg cm-2 s-1 is obtained. Conclusions: In the context of an existing theoretical model for the remnant, the lack of a detectable gamma-ray flux implies a distance of at least 6.4 kpc. A corresponding upper limit for the density of the ambient matter of 0.7 cm-3 is derived. With this distance limit, and assuming a spectral index Γ = 2, the total energy in accelerated protons is limited to Ep < 8.6 × 1049 erg. In the synchrotron/inverse Compton framework, extrapolating the power law measured by RXTE between 10 and 20 keV down in energy, the predicted gamma-ray flux from inverse Compton scattering is below the measured upper limit for magnetic field values greater than 52 μ G.

  7. Upper limit on Titan's atmospheric argon abundance

    NASA Astrophysics Data System (ADS)

    Strobel, D. F.; Hall, D. T.; Zhu, X.; Summers, M. E.

    1993-06-01

    An analysis is conducted on the Voyager 1 UV Spectrometer solar-occultation data and a Titan flyby spectrum of the north polar region dayglow, in order to infer the tropopausal Ar mixing ratio's upper limit as a function of the CH4 mixing ratio, f(CH4). The mole-fraction upper limit of tropopausal Ar mixing ratio ranges from 0.01 to 0.1 at f(CH4) of 0.026 to as low as 0.08 at f(CH4) of 0.05. Since the best fits to the solar occultation data require f(CH4) of more than 0.26, the Ar mixing ratio must be lower than 0.1.

  8. Upper limit on Titan's atmospheric argon abundance

    NASA Technical Reports Server (NTRS)

    Strobel, Darrell F.; Hall, Doyle T.; Zhu, Xun; Summers, Michael E.

    1993-01-01

    An analysis is conducted on the Voyager 1 UV Spectrometer solar-occultation data and a Titan flyby spectrum of the north polar region dayglow, in order to infer the tropopausal Ar mixing ratio's upper limit as a function of the CH4 mixing ratio, f(CH4). The mole-fraction upper limit of tropopausal Ar mixing ratio ranges from 0.01 to 0.1 at f(CH4) of 0.026 to as low as 0.08 at f(CH4) of 0.05. Since the best fits to the solar occultation data require f(CH4) of more than 0.26, the Ar mixing ratio must be lower than 0.1.

  9. An upper limit for stratospheric hydrogen peroxide

    NASA Technical Reports Server (NTRS)

    Chance, K. V.; Traub, W. A.

    1984-01-01

    It has been postulated that hydrogen peroxide is important in stratospheric chemistry as a reservoir and sink for odd hydrogen species, and for its ability to interconvert them. The present investigation is concerned with an altitude dependent upper limit curve for stratospheric hydrogen peroxide, taking into account an altitude range from 21.5 to 38.0 km for January 23, 1983. The data employed are from balloon flight No. 1316-P, launched from the National Scientific Balloon Facility (NSBF) in Palestine, Texas. The obtained upper limit curve lies substantially below the data reported by Waters et al. (1981), even though the results are from the same latitude and are both wintertime measurements.

  10. Upper plate absolute motion and slab-anchor force control on back-arc deformation

    NASA Astrophysics Data System (ADS)

    Heuret, A.; Lallemand, S.

    2003-04-01

    In order to test how the combined effects of overriding plate motion and trench migration can account for the variability of back-arc tectonic regimes, their "normal to the trench" absolute motion components and the strain regime of all oceanic subduction zones were compiled. Strain regime was estimated following Jarrard (1986), in a semiquantitative way. The upper plate absolute motion (Vup) is calculated in the hotspot HS3-NUVEL1A (Gripp and Gordon, 2002) reference frame and trench migration (Vt) from Vup, corrected from deformation rate of back-arc region, mainly given by GPS data. As slabs tend to sink because of their age-related-mass-excess relative to the surrounding mantle, it is generally assumed that most of the trenches have a spontaneous seaward motion (trench rollback). Ages at trench have thus also been compiled ( from Muller et al, 1997) to test a possible control of trench migration with slab age. Our values underline a high control of strain regime by Vup, but inconsistencies still remain with this single parameter. To account for all the observed deformations, trench migration is needed. There are more or less as much subduction zones with seaward Vt as landward ones, and, for 90% of subduction zones, Vt never reach 50 mm/y in the two directions. The expected relation between trench migration and slab age is far to be verified: landward trench migrations exist in many subduction zones, and, among them, many have old slabs. Several examples indicate that the slab tend to follow the trench migration and, so, to move transversely in the surrounding mantle. As a consequence, Vt is close to the "normal to the trench" slab migration and gives informations about the slab anchor force : slabs are not perfectly anchored but their possible motions appear to be limited. This 50 mm/y limitation of slab migration may provide new constraints on the poorly known slab-anchor force. No evidence of age related trench rollback have beeen found. It does not

  11. System providing limit switch function with simultaneous absolute position output

    NASA Technical Reports Server (NTRS)

    Alhorn, Dean C. (Inventor); Howard, David E. (Inventor); Smith, Dennis A. (Inventor)

    2006-01-01

    A limit and position sensing system includes a sensor assembly and an emitter. The sensor assembly includes first and second electrical conductors arranged in opposing parallel planes. The first electrical conductor is coiled outwardly from either end thereof in a clockwise fashion to form a first coil region and a second coil region. The second electrical conductor forms a single coil with portions of the single coil's rings lying between the first end and second end of the first electrical conductor being parallel to an axis of the first electrical conductor's plane. Ferromagnetic material is aligned with the first and second electrical conductors and spans beyond (a) the first and second ends of the first electrical conductor, and (b) the portions of the rings of the second electrical conductor's single coil that lie between the first end and second end of the first electrical conductor. The emitter is spaced apart from the sensor assembly and transmits a periodic electromagnetic wave towards the sensor assembly.

  12. 40 CFR 86.1104-91 - Determination of upper limits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) Nonconformance Penalties for Gasoline-Fueled and Diesel Heavy-Duty Engines and Heavy-Duty Vehicles, Including Light-Duty Trucks § 86.1104-91 Determination of upper limits. (a) The upper limit applicable to...

  13. 40 CFR 86.1104-91 - Determination of upper limits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) Nonconformance Penalties for Gasoline-Fueled and Diesel Heavy-Duty Engines and Heavy-Duty Vehicles, Including Light-Duty Trucks § 86.1104-91 Determination of upper limits. (a) The upper limit applicable to...

  14. 40 CFR 86.1104-91 - Determination of upper limits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES Nonconformance Penalties for Gasoline-Fueled and Diesel Heavy-Duty Engines and Heavy-Duty Vehicles, Including Light-Duty Trucks § 86.1104-91 Determination of upper limits. EPA shall set a separate upper limit for each phase...

  15. 40 CFR 86.1104-91 - Determination of upper limits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) Nonconformance Penalties for Gasoline-Fueled and Diesel Heavy-Duty Engines and Heavy-Duty Vehicles, Including Light-Duty Trucks § 86.1104-91 Determination of upper limits. EPA shall set a separate upper limit...

  16. 40 CFR 86.1104-91 - Determination of upper limits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES (CONTINUED) Nonconformance Penalties for Gasoline-Fueled and Diesel Heavy-Duty Engines and Heavy-Duty Vehicles, Including Light-Duty Trucks § 86.1104-91 Determination of upper limits. EPA shall set a separate upper limit...

  17. Upper limit map of a background of gravitational waves

    NASA Astrophysics Data System (ADS)

    Abbott, B.; Abbott, R.; Adhikari, R.; Agresti, J.; Ajith, P.; Allen, B.; Amin, R.; Anderson, S. B.; Anderson, W. G.; Arain, M.; Araya, M.; Armandula, H.; Ashley, M.; Aston, S.; Aufmuth, P.; Aulbert, C.; Babak, S.; Ballmer, S.; Bantilan, H.; Barish, B. C.; Barker, C.; Barker, D.; Barr, B.; Barriga, P.; Barton, M. A.; Bayer, K.; Belczynski, K.; Betzwieser, J.; Beyersdorf, P. T.; Bhawal, B.; Bilenko, I. A.; Billingsley, G.; Biswas, R.; Black, E.; Blackburn, K.; Blackburn, L.; Blair, D.; Bland, B.; Bogenstahl, J.; Bogue, L.; Bork, R.; Boschi, V.; Bose, S.; Brady, P. R.; Braginsky, V. B.; Brau, J. E.; Brinkmann, M.; Brooks, A.; Brown, D. A.; Bullington, A.; Bunkowski, A.; Buonanno, A.; Burmeister, O.; Busby, D.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Camp, J. B.; Cannizzo, J.; Cannon, K.; Cantley, C. A.; Cao, J.; Cardenas, L.; Casey, M. M.; Castaldi, G.; Cepeda, C.; Chalkey, E.; Charlton, P.; Chatterji, S.; Chelkowski, S.; Chen, Y.; Chiadini, F.; Chin, D.; Chin, E.; Chow, J.; Christensen, N.; Clark, J.; Cochrane, P.; Cokelaer, T.; Colacino, C. N.; Coldwell, R.; Conte, R.; Cook, D.; Corbitt, T.; Coward, D.; Coyne, D.; Creighton, J. D. E.; Creighton, T. D.; Croce, R. P.; Crooks, D. R. M.; Cruise, A. M.; Cumming, A.; Dalrymple, J.; D'Ambrosio, E.; Danzmann, K.; Davies, G.; Debra, D.; Degallaix, J.; Degree, M.; Demma, T.; Dergachev, V.; Desai, S.; Desalvo, R.; Dhurandhar, S.; Díaz, M.; Dickson, J.; di Credico, A.; Diederichs, G.; Dietz, A.; Doomes, E. E.; Drever, R. W. P.; Dumas, J.-C.; Dupuis, R. J.; Dwyer, J. G.; Ehrens, P.; Espinoza, E.; Etzel, T.; Evans, M.; Evans, T.; Fairhurst, S.; Fan, Y.; Fazi, D.; Fejer, M. M.; Finn, L. S.; Fiumara, V.; Fotopoulos, N.; Franzen, A.; Franzen, K. Y.; Freise, A.; Frey, R.; Fricke, T.; Fritschel, P.; Frolov, V. V.; Fyffe, M.; Galdi, V.; Garofoli, J.; Gholami, I.; Giaime, J. A.; Giampanis, S.; Giardina, K. D.; Goda, K.; Goetz, E.; Goggin, L. M.; González, G.; Gossler, S.; Grant, A.; Gras, S.; Gray, C.; Gray, M.; Greenhalgh, J.; Gretarsson, A. M.; Grosso, R.; Grote, H.; Grunewald, S.; Guenther, M.; Gustafson, R.; Hage, B.; Hammer, D.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G.; Harstad, E.; Hayler, T.; Heefner, J.; Heng, I. S.; Heptonstall, A.; Heurs, M.; Hewitson, M.; Hild, S.; Hirose, E.; Hoak, D.; Hosken, D.; Hough, J.; Howell, E.; Hoyland, D.; Huttner, S. H.; Ingram, D.; Innerhofer, E.; Ito, M.; Itoh, Y.; Ivanov, A.; Jackrel, D.; Johnson, B.; Johnson, W. W.; Jones, D. I.; Jones, G.; Jones, R.; Ju, L.; Kalmus, P.; Kalogera, V.; Kasprzyk, D.; Katsavounidis, E.; Kawabe, K.; Kawamura, S.; Kawazoe, F.; Kells, W.; Keppel, D. G.; Khalili, F. Ya.; Kim, C.; King, P.; Kissel, J. S.; Klimenko, S.; Kokeyama, K.; Kondrashov, V.; Kopparapu, R. K.; Kozak, D.; Krishnan, B.; Kwee, P.; Lam, P. K.; Landry, M.; Lantz, B.; Lazzarini, A.; Lee, B.; Lei, M.; Leiner, J.; Leonhardt, V.; Leonor, I.; Libbrecht, K.; Lindquist, P.; Lockerbie, N. A.; Longo, M.; Lormand, M.; Lubiński, M.; Lück, H.; Machenschalk, B.; Macinnis, M.; Mageswaran, M.; Mailand, K.; Malec, M.; Mandic, V.; Marano, S.; Márka, S.; Markowitz, J.; Maros, E.; Martin, I.; Marx, J. N.; Mason, K.; Matone, L.; Matta, V.; Mavalvala, N.; McCarthy, R.; McClelland, D. E.; McGuire, S. C.; McHugh, M.; McKenzie, K.; McNabb, J. W. C.; McWilliams, S.; Meier, T.; Melissinos, A.; Mendell, G.; Mercer, R. A.; Meshkov, S.; Messaritaki, E.; Messenger, C. J.; Meyers, D.; Mikhailov, E.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Miyakawa, O.; Mohanty, S.; Moreno, G.; Mossavi, K.; Mowlowry, C.; Moylan, A.; Mudge, D.; Mueller, G.; Mukherjee, S.; Müller-Ebhardt, H.; Munch, J.; Murray, P.; Myers, E.; Myers, J.; Newton, G.; Nishizawa, A.; Numata, K.; O'Reilly, B.; O'Shaughnessy, R.; Ottaway, D. J.; Overmier, H.; Owen, B. J.; Pan, Y.; Papa, M. A.; Parameshwaraiah, V.; Patel, P.; Pedraza, M.; Penn, S.; Pierro, V.; Pinto, I. M.; Pitkin, M.; Pletsch, H.; Plissi, M. V.; Postiglione, F.; Prix, R.; Quetschke, V.; Raab, F.; Rabeling, D.; Radkins, H.; Rahkola, R.; Rainer, N.; Rakhmanov, M.; Rawlins, K.; Ray-Majumder, S.; Re, V.; Rehbein, H.; Reid, S.; Reitze, D. H.; Ribichini, L.; Riesen, R.; Riles, K.; Rivera, B.; Robertson, N. A.; Robinson, C.; Robinson, E. L.; Roddy, S.; Rodriguez, A.; Rogan, A. M.; Rollins, J.; Romano, J. D.; Romie, J.; Route, R.; Rowan, S.; Rüdiger, A.; Ruet, L.; Russell, P.; Ryan, K.; Sakata, S.; Samidi, M.; Sancho de La Jordana, L.; Sandberg, V.; Sannibale, V.; Saraf, S.; Sarin, P.; Sathyaprakash, B. S.; Sato, S.; Saulson, P. R.; Savage, R.; Savov, P.; Schediwy, S.; Schilling, R.; Schnabel, R.; Schofield, R.; Schutz, B. F.; Schwinberg, P.; Scott, S. M.; Searle, A. C.; Sears, B.; Seifert, F.; Sellers, D.; Sengupta, A. S.; Shawhan, P.; Shoemaker, D. H.; Sibley, A.; Sidles, J. A.; Siemens, X.; Sigg, D.; Sinha, S.; Sintes, A. M.; Slagmolen, B. J. J.; Slutsky, J.; Smith, J. R.; Smith, M. R.; Somiya, K.; Strain, K. A.; Strom, D. M.; Stuver, A.; Summerscales, T. Z.; Sun, K.-X.; Sung, M.; Sutton, P. J.; Takahashi, H.; Tanner, D. B.; Tarallo, M.; Taylor, R.; Taylor, R.; Thacker, J.; Thorne, K. A.; Thorne, K. S.; Thüring, A.; Tokmakov, K. V.; Torres, C.; Torrie, C.; Traylor, G.; Trias, M.; Tyler, W.; Ugolini, D.; Ungarelli, C.; Urbanek, K.; Vahlbruch, H.; Vallisneri, M.; van den Broeck, C.; Varvella, M.; Vass, S.; Vecchio, A.; Veitch, J.; Veitch, P.; Villar, A.; Vorvick, C.; Vyachanin, S. P.; Waldman, S. J.; Wallace, L.; Ward, H.; Ward, R.; Watts, K.; Webber, D.; Weidner, A.; Weinert, M.; Weinstein, A.; Weiss, R.; Wen, S.; Wette, K.; Whelan, J. T.; Whitbeck, D. M.; Whitcomb, S. E.; Whiting, B. F.; Wilkinson, C.; Willems, P. A.; Williams, L.; Willke, B.; Wilmut, I.; Winkler, W.; Wipf, C. C.; Wise, S.; Wiseman, A. G.; Woan, G.; Woods, D.; Wooley, R.; Worden, J.; Wu, W.; Yakushin, I.; Yamamoto, H.; Yan, Z.; Yoshida, S.; Yunes, N.; Zanolin, M.; Zhang, J.; Zhang, L.; Zhao, C.; Zotov, N.; Zucker, M.; Zur Mühlen, H.; Zweizig, J.

    2007-10-01

    We searched for an anisotropic background of gravitational waves using data from the LIGO S4 science run and a method that is optimized for point sources. This is appropriate if, for example, the gravitational wave background is dominated by a small number of distinct astrophysical sources. No signal was seen. Upper limit maps were produced assuming two different power laws for the source strain power spectrum. For an f-3 power law and using the 50 Hz to 1.8 kHz band the upper limits on the source strain power spectrum vary between 1.2×10-48Hz-1 (100Hz/f)3 and 1.2×10-47Hz-1 (100Hz/f)3, depending on the position in the sky. Similarly, in the case of constant strain power spectrum, the upper limits vary between 8.5×10-49Hz-1 and 6.1×10-48Hz-1. As a side product a limit on an isotropic background of gravitational waves was also obtained. All limits are at the 90% confidence level. Finally, as an application, we focused on the direction of Sco-X1, the brightest low-mass x-ray binary. We compare the upper limit on strain amplitude obtained by this method to expectations based on the x-ray flux from Sco-X1.

  18. Is there an upper limit to fermion masses

    SciTech Connect

    Einhorn, M.B.; Goldberg, G.J.

    1986-10-27

    A fermion mass generated by spontaneous symmetry breaking is proportional to its Yukawa coupling y to a Higgs field. Like the Higgs-field self-coupling, y may well be trivial and diverge at a finite energy scale ..lambda../sub f/, corresponding to an upper limit on fermion masses. We verify this by solving a simple model by means of a 1/N expansion. Applied to the standard model, this suggests that there is an upper limit to quark and lepton masses. These results have implications for the ''decoupling'' of heavy fermions and bear on the issue of whether apparently ''anomalous'' gauge theories can be consistently quantized.

  19. The upper limits of pain and suffering in animal research.

    PubMed

    Beauchamp, Tom L; Morton, David B

    2015-10-01

    The control of risk and harm in human research often calls for the establishment of upper limits of risk of pain, suffering, and distress that investigators must not exceed. Such upper limits are uncommon in animal research, in which limits of acceptability are usually left to the discretion of individual investigators, institutions, national inspectors, or ethics review committees. We here assess the merits of the European Directive 2010/63/EU on the Protection of Animals Used for Scientific Purposes and its accompanying instruments, such as guides and examples. These documents present a body of legislation governing animal research in the European Union. We argue that the directive supplies a promising approach, but one in need of revision. We interpret the directive's general conception of upper limits and show its promise for the establishment of high-quality policies. We provide a moral rationale for such policies, address the problem of justified exceptions to established upper limits, and show when causing harm is and is not wrongful. We conclude that if the standards we propose for improving the directive are not realized in the review of research protocols, loose and prejudicial risk-benefit assessments may continue to be deemed sufficient to justify morally questionable research. However, a revised EU directive and accompanying instruments could have a substantial influence on the ethics of animal research worldwide, especially in the development of morally sound legal frameworks.

  20. The upper limits of pain and suffering in animal research.

    PubMed

    Beauchamp, Tom L; Morton, David B

    2015-10-01

    The control of risk and harm in human research often calls for the establishment of upper limits of risk of pain, suffering, and distress that investigators must not exceed. Such upper limits are uncommon in animal research, in which limits of acceptability are usually left to the discretion of individual investigators, institutions, national inspectors, or ethics review committees. We here assess the merits of the European Directive 2010/63/EU on the Protection of Animals Used for Scientific Purposes and its accompanying instruments, such as guides and examples. These documents present a body of legislation governing animal research in the European Union. We argue that the directive supplies a promising approach, but one in need of revision. We interpret the directive's general conception of upper limits and show its promise for the establishment of high-quality policies. We provide a moral rationale for such policies, address the problem of justified exceptions to established upper limits, and show when causing harm is and is not wrongful. We conclude that if the standards we propose for improving the directive are not realized in the review of research protocols, loose and prejudicial risk-benefit assessments may continue to be deemed sufficient to justify morally questionable research. However, a revised EU directive and accompanying instruments could have a substantial influence on the ethics of animal research worldwide, especially in the development of morally sound legal frameworks. PMID:26364778

  1. Absolute stability window and upper bound on the magnetic field strength in a strongly magnetized strange quark star

    NASA Astrophysics Data System (ADS)

    Isayev, A. A.

    2014-11-01

    Magnetized strange quark stars, composed of strange quark matter (SQM) and self-bound by strong interactions, can be formed if the energy per baryon of magnetized SQM is less than that of the most stable 56Fe nucleus under the zero external pressure and temperature. Utilizing the MIT bag model description of magnetized SQM under charge neutrality and beta equilibrium conditions, the corresponding absolute stability window in the parameter space of the theory is determined. It is shown that there exists the maximum magnetic field strength allowed by the condition of absolute stability of magnetized SQM. The value of this field, H 3 × 1018G, represents the upper bound on the magnetic field strength which can be reached in a strongly magnetized strange quark star.

  2. Upward excursion limits from air saturation at 5 ATA (Atmospheres Absolute)

    NASA Astrophysics Data System (ADS)

    Parker, James W.

    1989-01-01

    Present USN submarine rescue capability makes a prolonged exposure of the submarine crew to hyperbaric air a distinct possibility. The exposure may be to pressures as great as 5 atmospheres absolute (ATA), and for periods of time of up to 72 hours. A series of experimental dives were conducted to establish the safe, upward excursion from 5 ATA (132 FSWG); that is, the maximum, immediate reduction in pressure which these individuals can safely tolerate. This specifies the required pressure in the compartment of a mother submarine to which the rescued personnel would be transferred. In order to minimize the effects of pulmonary oxygen toxicity, the limits first were established using a nitrox equivalent of air at 5 ATA. The upward limit from 4.36 ATA (111 FSWG) was found to be 2.97 ATA (65 FSWG). Once this limit had been set, a series of dives were conducted to test this up limit from standard air at 5 ATA.

  3. 42 CFR 447.304 - Adherence to upper limits; FFP.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Adherence to upper limits; FFP. 447.304 Section 447.304 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... experiments conducted under section 402 of Pub. L. 90-428, Incentives for Economy Experimentation, as...

  4. 42 CFR 447.304 - Adherence to upper limits; FFP.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 4 2014-10-01 2014-10-01 false Adherence to upper limits; FFP. 447.304 Section 447.304 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS PAYMENTS FOR SERVICES Payment Methods for Other Institutional...

  5. 42 CFR 447.304 - Adherence to upper limits; FFP.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 4 2012-10-01 2012-10-01 false Adherence to upper limits; FFP. 447.304 Section 447.304 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS PAYMENTS FOR SERVICES Payment Methods for Other Institutional...

  6. 42 CFR 447.304 - Adherence to upper limits; FFP.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 4 2013-10-01 2013-10-01 false Adherence to upper limits; FFP. 447.304 Section 447.304 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS PAYMENTS FOR SERVICES Payment Methods for Other Institutional and Noninstitutional Services §...

  7. 42 CFR 447.304 - Adherence to upper limits; FFP.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Adherence to upper limits; FFP. 447.304 Section 447.304 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS PAYMENTS FOR SERVICES Payment Methods for Other Institutional...

  8. Improved upper limit on the photon rest mass

    NASA Technical Reports Server (NTRS)

    Barnes, A.; Scargle, J. D.

    1975-01-01

    It is shown that application of standard MHD arguments to hydromagnetic waves observed in the Crab Nebula dramatically improves the upper bound on photon rest mass. The standard argument that massive photons are governed by the Phoca field equations is outlined and applied to wisp features (identified as hydromagnetic waves) observed in the Crab. The results imply an upper limit for the photon rest mass of between 3 by 10 to the -54th power and 3 by 10 to the -53rd power gram, which is smaller than the best previous limits by a factor of 10,000 to 100,000. It is noted that although the present limit is probably valid in order of magnitude, some doubt remains since there are inconsistencies in the standard arguments.

  9. An observed upper limit on stratospheric hydrogen peroxide

    NASA Technical Reports Server (NTRS)

    De Zafra, R. L.; Parrish, A.; Barrett, J.; Solomon, P.

    1985-01-01

    Observations collected by a ground-based heterodyne receiver of an emission from the 7(0.7)-6(1.5) rotational torsional transition of H2O2 at 270.610 GHz are studied. An integrated spectrometer output of the data obtained at Mauna Kea, Hawaii in late May and early June of 1983 is presented. The removal of the ozone line background profile from the data is described. With no signal detected in the output of a 256-channel filter spectrometer the calculation of an upper limit on stratospheric H2O2 is possible. The utilization of the mixing ratio profile of Sze and Ko (1984) to compute the limit of H2O2 is examined. An upper limit for H2O2 of approximately 1 x 10 to the 14th/cu cm between 30-50 km is established.

  10. Evolutionary capacity of upper thermal limits: beyond single trait assessments.

    PubMed

    Blackburn, Shaun; van Heerwaarden, Belinda; Kellermann, Vanessa; Sgrò, Carla M

    2014-06-01

    Thermal tolerance is an important factor influencing the distribution of ectotherms, but we still have limited understanding of the ability of species to evolve different thermal limits. Recent studies suggest that species may have limited capacity to evolve higher thermal limits in response to slower, more ecologically relevant rates of warming. However, these conclusions are based on univariate estimates of adaptive capacity. To test these findings within an explicitly multivariate context, we used a paternal half-sibling breeding design to estimate the multivariate evolutionary potential for upper thermal limits in Drosophila melanogaster. We assessed heat tolerance using static (basal and hardened) and ramping assays. Additive genetic variances were significantly different from zero only for the static measures of heat tolerance. Our G: matrix analysis revealed that any response to selection for increased heat tolerance will largely be driven by static basal and hardened heat tolerance, with minimal contribution from ramping heat tolerance. These results suggest that the capacity to evolve upper thermal limits in nature may depend on the type of thermal stress experienced.

  11. Upper thermal tolerance and oxygen limitation in terrestrial arthropods.

    PubMed

    Klok, C Jaco; Sinclair, Brent J; Chown, Steven L

    2004-06-01

    The hypothesis of oxygen limitation of thermal tolerance proposes that critical temperatures are set by a transition to anaerobic metabolism, and that upper and lower tolerances are therefore coupled. Moreover, this hypothesis has been dubbed a unifying general principle and extended from marine to terrestrial ectotherms. By contrast, in insects the upper and lower limits are decoupled, suggesting that the oxygen limitation hypothesis might not be as general as proposed. However, no direct tests of this hypothesis or its predictions have been undertaken in terrestrial species. We use a terrestrial isopod (Armadillidium vulgare) and a tenebrionid beetle (Gonocephalum simplex) to test the prediction that thermal tolerance should vary with oxygen partial pressure. Whilst in the isopod critical thermal maximum declined with declining oxygen concentration, this was not the case in the beetle. Efficient oxygen delivery via a tracheal system makes oxygen limitation of thermal tolerance, at a whole organism level, unlikely in insects. By contrast, oxygen limitation of thermal tolerances is expected to apply to species, like the isopod, in which the circulatory system contributes significantly to oxygen delivery. Because insects dominate terrestrial systems, oxygen limitation of thermal tolerance cannot be considered pervasive in this habitat, although it is a characteristic of marine species. PMID:15159440

  12. An upper limit on the neutrino rest mass.

    NASA Technical Reports Server (NTRS)

    Cowsik, R.; Mcclelland, J.

    1972-01-01

    It is pointed out that the measurement of the deceleration parameter by Sandage (1972) implies an upper limit of a few tens of electron volts on the sum of the masses of all the possible light, stable particles that interact only weakly. In the discussion of the problem, it is assumed that the universe is expanding from an initially hot and condensed state as envisaged in the 'big-bang' theories.

  13. Upper limit of magnetic effect on α/β ratio

    NASA Astrophysics Data System (ADS)

    Pang, G.

    2015-09-01

    Magnetic resonance imaging (MRI) is being integrated into radiotherapy delivery for MRI-guided radiotherapy. The purpose of this work is to investigate theoretically the upper limit of any potential magnetic effect on the α/β ratio, an important radiobiological parameter in radiation therapy. Based on the theory of dual radiation action, the α/β ratio can be expressed by an integral of the product of two microdosimetry quantities γ (x) and t(x) , where γ (x) is the probability that two energy transfers, a distance x apart, results in a lesion, and t(x) is the proximity function, which is the energy-weighted point-pair distribution of distances between energy transfer points in a track. The quantity t(x) depends on the applied magnetic field. An analytical approach has been used to derive a formula that can be used to calculate the α/β ratio in an extremely strong magnetic field, which gives the upper limit of the potential changes of the α/β ratio due to the presence of a magnetic field. For V79 Chinese hamster cells the upper limit of the increase of the α/β ratio with a magnetic field has been found to be 2.90 times for Pd-103, 2.97 times for I-125 and 2.3 times for Co-60 sources.

  14. Upper limit for sea level projections by 2100

    NASA Astrophysics Data System (ADS)

    Jevrejeva, S.; Grinsted, A.; Moore, J. C.

    2014-10-01

    We construct the probability density function of global sea level at 2100, estimating that sea level rises larger than 180 cm are less than 5% probable. An upper limit for global sea level rise of 190 cm is assembled by summing the highest estimates of individual sea level rise components simulated by process based models with the RCP8.5 scenario. The agreement between the methods may suggest more confidence than is warranted since large uncertainties remain due to the lack of scenario-dependent projections from ice sheet dynamical models, particularly for mass loss from marine-based fast flowing outlet glaciers in Antarctica. This leads to an intrinsically hard to quantify fat tail in the probability distribution for global mean sea level rise. Thus our low probability upper limit of sea level projections cannot be considered definitive. Nevertheless, our upper limit of 180 cm for sea level rise by 2100 is based on both expert opinion and process studies and hence indicates that other lines of evidence are needed to justify a larger sea level rise this century.

  15. Absolute density measurement of SD radicals in a supersonic jet at the quantum-noise-limit.

    PubMed

    Mizouri, Arin; Deng, L Z; Eardley, Jack S; Nahler, N Hendrik; Wrede, Eckart; Carty, David

    2013-12-01

    The absolute density of SD radicals in a supersonic jet has been measured down to (1.1 ± 0.1) × 10(5) cm(-3) in a modestly specified apparatus that uses a cross-correlated combination of cavity ring-down and laser-induced fluorescence detection. Such a density corresponds to 215 ± 21 molecules in the probe volume at any given time. The minimum detectable absorption coefficient was quantum-noise-limited and measured to be (7.9 ± 0.6) × 10(-11) cm(-1), in 200 s of acquisition time, corresponding to a noise-equivalent absorption sensitivity for the apparatus of (1.6 ± 0.1) × 10(-9) cm(-1) Hz(-1/2).

  16. Combined upper limit for SM Higgs at the Tevatron

    SciTech Connect

    Penning, Bjorn; /Fermilab

    2009-01-01

    We combine results from CDF and D0 on direct searches for a standard model (SM) Higgs boson (H) in p{bar p} collisions at the Fermilab Tevatron at {radical}s = 1.96 TeV. Compared to the previous Higgs Tevatron combination, more data and new channels (WH {yields} {tau}{nu}b{bar b}, VH {yields} {tau}{tau}b{bar b}/jj{tau}{tau}, VH {yields} jjb{bar b}, t{bar t}H {yields} t{bar t}b{bar b}) have been added. Most previously used channels have been reanalyzed to gain sensitivity. We use the latest parton distribution functions and gg {yields} H theoretical cross sections when comparing our limits to the SM predictions. With 2.0-3.6 fb{sup -1} of data analyzed at CDF, and 0.9-4.2 fb{sup -1} at D0, the 95%C.L. upper limits on Higgs boson production are a factor of 2.5 (0.86) times the SM cross section for a Higgs boson mass of m{sub H} = 115 (165) GeV/c{sup 2}. Based on simulation, the corresponding median expected upper limits are 2.4 (1.1). The mass range excluded at 95% C.L. for a SM Higgs has been extended to 160 < m{sub H} < 170 GeV/c{sup 2}.

  17. Upper limits on a stochastic background of gravitational waves.

    PubMed

    Abbott, B; Abbott, R; Adhikari, R; Agresti, J; Ajith, P; Allen, B; Allen, J; Amin, R; Anderson, S B; Anderson, W G; Araya, M; Armandula, H; Ashley, M; Aulbert, C; Babak, S; Balasubramanian, R; Ballmer, S; Barish, B C; Barker, C; Barker, D; Barton, M A; Bayer, K; Belczynski, K; Betzwieser, J; Bhawal, B; Bilenko, I A; Billingsley, G; Black, E; Blackburn, K; Blackburn, L; Bland, B; Bogue, L; Bork, R; Bose, S; Brady, P R; Braginsky, V B; Brau, J E; Brown, D A; Buonanno, A; Busby, D; Butler, W E; Cadonati, L; Cagnoli, G; Camp, J B; Cannizzo, J; Cannon, K; Cardenas, L; Carter, K; Casey, M M; Charlton, P; Chatterji, S; Chen, Y; Chin, D; Christensen, N; Cokelaer, T; Colacino, C N; Coldwell, R; Cook, D; Corbitt, T; Coyne, D; Creighton, J D E; Creighton, T D; Dalrymple, J; D'Ambrosio, E; Danzmann, K; Davies, G; DeBra, D; Dergachev, V; Desai, S; DeSalvo, R; Dhurandar, S; Díaz, M; Di Credico, A; Drever, R W P; Dupuis, R J; Ehrens, P; Etzel, T; Evans, M; Evans, T; Fairhurst, S; Finn, L S; Franzen, K Y; Frey, R E; Fritschel, P; Frolov, V V; Fyffe, M; Ganezer, K S; Garofoli, J; Gholami, I; Giaime, J A; Goda, K; Goggin, L; González, G; Gray, C; Gretarsson, A M; Grimmett, D; Grote, H; Grunewald, S; Guenther, M; Gustafson, R; Hamilton, W O; Hanna, C; Hanson, J; Hardham, C; Harry, G; Heefner, J; Heng, I S; Hewitson, M; Hindman, N; Hoang, P; Hough, J; Hua, W; Ito, M; Itoh, Y; Ivanov, A; Johnson, B; Johnson, W W; Jones, D I; Jones, G; Jones, L; Kalogera, V; Katsavounidis, E; Kawabe, K; Kawamura, S; Kells, W; Khan, A; Kim, C; King, P; Klimenko, S; Koranda, S; Kozak, D; Krishnan, B; Landry, M; Lantz, B; Lazzarini, A; Lei, M; Leonor, I; Libbrecht, K; Lindquist, P; Liu, S; Lormand, M; Lubinski, M; Lück, H; Luna, M; Machenschalk, B; MacInnis, M; Mageswaran, M; Mailand, K; Malec, M; Mandic, V; Marka, S; Maros, E; Mason, K; Matone, L; Mavalvala, N; McCarthy, R; McClelland, D E; McHugh, M; McNabb, J W C; Melissinos, A; Mendell, G; Mercer, R A; Meshkov, S; Messaritaki, E; Messenger, C; Mikhailov, E; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Miyakawa, O; Mohanty, S; Moreno, G; Mossavi, K; Mueller, G; Mukherjee, S; Myers, E; Myers, J; Nash, T; Nocera, F; Noel, J S; O'Reilly, B; O'Shaughnessy, R; Ottaway, D J; Overmier, H; Owen, B J; Pan, Y; Papa, M A; Parameshwaraiah, V; Parameswariah, C; Pedraza, M; Penn, S; Pitkin, M; Prix, R; Quetschke, V; Raab, F; Radkins, H; Rahkola, R; Rakhmanov, M; Rawlins, K; Ray-Majumder, S; Re, V; Regimbau, T; Reitze, D H; Riesen, R; Riles, K; Rivera, B; Robertson, D I; Robertson, N A; Robinson, C; Roddy, S; Rodriguez, A; Rollins, J; Romano, J D; Romie, J; Rowan, S; Rüdiger, A; Ruet, L; Russell, P; Ryan, K; Sandberg, V; Sanders, G H; Sannibale, V; Sarin, P; Sathyaprakash, B S; Saulson, P R; Savage, R; Sazonov, A; Schilling, R; Schofield, R; Schutz, B F; Schwinberg, P; Scott, S M; Seader, S E; Searle, A C; Sears, B; Sellers, D; Sengupta, A S; Shawhan, P; Shoemaker, D H; Sibley, A; Siemens, X; Sigg, D; Sintes, A M; Smith, J; Smith, M R; Spjeld, O; Strain, K A; Strom, D M; Stuver, A; Summerscales, T; Sung, M; Sutton, P J; Tanner, D B; Taylor, R; Thorne, K A; Thorne, K S; Tokmakov, K V; Torres, C; Torrie, C; Traylor, G; Tyler, W; Ugolini, D; Ungarelli, C; Vallisneri, M; van Putten, M; Vass, S; Vecchio, A; Veitch, J; Vorvick, C; Vyachanin, S P; Wallace, L; Ward, H; Ward, R; Watts, K; Webber, D; Weiland, U; Weinstein, A; Weiss, R; Wen, S; Wette, K; Whelan, J T; Whitcomb, S E; Whiting, B F; Wiley, S; Wilkinson, C; Willems, P A; Willke, B; Wilson, A; Winkler, W; Wise, S; Wiseman, A G; Woan, G; Woods, D; Wooley, R; Worden, J; Yakushin, I; Yamamoto, H; Yoshida, S; Zanolin, M; Zhang, L; Zotov, N; Zucker, M; Zweizig, J

    2005-11-25

    The Laser Interferometer Gravitational-Wave Observatory has performed a third science run with much improved sensitivities of all three interferometers. We present an analysis of approximately 200 hours of data acquired during this run, used to search for a stochastic background of gravitational radiation. We place upper bounds on the energy density stored as gravitational radiation for three different spectral power laws. For the flat spectrum, our limit of omega0 < 8.4 x 10(-4) in the 69-156 Hz band is approximately 10(5) times lower than the previous result in this frequency range. PMID:16384203

  18. Low upper limit to methane abundance on Mars.

    PubMed

    Webster, Christopher R; Mahaffy, Paul R; Atreya, Sushil K; Flesch, Gregory J; Farley, Kenneth A

    2013-10-18

    By analogy with Earth, methane in the Martian atmosphere is a potential signature of ongoing or past biological activity. During the past decade, Earth-based telescopic observations reported "plumes" of methane of tens of parts per billion by volume (ppbv), and those from Mars orbit showed localized patches, prompting speculation of sources from subsurface bacteria or nonbiological sources. From in situ measurements made with the Tunable Laser Spectrometer (TLS) on Curiosity using a distinctive spectral pattern specific to methane, we report no detection of atmospheric methane with a measured value of 0.18 ± 0.67 ppbv corresponding to an upper limit of only 1.3 ppbv (95% confidence level), which reduces the probability of current methanogenic microbial activity on Mars and limits the recent contribution from extraplanetary and geologic sources.

  19. Low Upper Limit to Methane Abundance on Mars

    NASA Astrophysics Data System (ADS)

    Webster, Christopher R.; Mahaffy, Paul R.; Atreya, Sushil K.; Flesch, Gregory J.; Farley, Kenneth A.; Kemppinen, Osku; Bridges, Nathan; Johnson, Jeffrey R.; Minitti, Michelle; Cremers, David; Bell, James F.; Edgar, Lauren; Farmer, Jack; Godber, Austin; Wadhwa, Meenakshi; Wellington, Danika; McEwan, Ian; Newman, Claire; Richardson, Mark; Charpentier, Antoine; Peret, Laurent; King, Penelope; Blank, Jennifer; Weigle, Gerald; Schmidt, Mariek; Li, Shuai; Milliken, Ralph; Robertson, Kevin; Sun, Vivian; Baker, Michael; Edwards, Christopher; Ehlmann, Bethany; Farley, Kenneth; Griffes, Jennifer; Grotzinger, John; Miller, Hayden; Newcombe, Megan; Pilorget, Cedric; Rice, Melissa; Siebach, Kirsten; Stack, Katie; Stolper, Edward; Brunet, Claude; Hipkin, Victoria; Léveillé, Richard; Marchand, Geneviève; Sánchez, Pablo Sobrón; Favot, Laurent; Cody, George; Steele, Andrew; Flückiger, Lorenzo; Lees, David; Nefian, Ara; Martin, Mildred; Gailhanou, Marc; Westall, Frances; Israël, Guy; Agard, Christophe; Baroukh, Julien; Donny, Christophe; Gaboriaud, Alain; Guillemot, Philippe; Lafaille, Vivian; Lorigny, Eric; Paillet, Alexis; Pérez, René; Saccoccio, Muriel; Yana, Charles; Armiens-Aparicio, Carlos; Rodríguez, Javier Caride; Blázquez, Isaías Carrasco; Gómez, Felipe Gómez; Elvira, Javier Gómez; Hettrich, Sebastian; Malvitte, Alain Lepinette; Jiménez, Mercedes Marín; Martínez-Frías, Jesús; Soler, Javier Martín; Martín-Torres, F. Javier; Jurado, Antonio Molina; Mora-Sotomayor, Luis; Caro, Guillermo Muñoz; López, Sara Navarro; Peinado-González, Verónica; Pla-García, Jorge; Manfredi, José Antonio Rodriguez; Romeral-Planelló, Julio José; Fuentes, Sara Alejandra Sans; Martinez, Eduardo Sebastian; Redondo, Josefina Torres; Urqui-O'Callaghan, Roser; Mier, María-Paz Zorzano; Chipera, Steve; Lacour, Jean-Luc; Mauchien, Patrick; Sirven, Jean-Baptiste; Manning, Heidi; Fairén, Alberto; Hayes, Alexander; Joseph, Jonathan; Squyres, Steven; Sullivan, Robert; Thomas, Peter; Dupont, Audrey; Lundberg, Angela; Melikechi, Noureddine; Mezzacappa, Alissa; DeMarines, Julia; Grinspoon, David; Reitz, Günther; Prats, Benito; Atlaskin, Evgeny; Genzer, Maria; Harri, Ari-Matti; Haukka, Harri; Kahanpää, Henrik; Kauhanen, Janne; Kemppinen, Osku; Paton, Mark; Polkko, Jouni; Schmidt, Walter; Siili, Tero; Fabre, Cécile; Wray, James; Wilhelm, Mary Beth; Poitrasson, Franck; Patel, Kiran; Gorevan, Stephen; Indyk, Stephen; Paulsen, Gale; Gupta, Sanjeev; Bish, David; Schieber, Juergen; Gondet, Brigitte; Langevin, Yves; Geffroy, Claude; Baratoux, David; Berger, Gilles; Cros, Alain; d'Uston, Claude; Forni, Olivier; Gasnault, Olivier; Lasue, Jérémie; Lee, Qiu-Mei; Maurice, Sylvestre; Meslin, Pierre-Yves; Pallier, Etienne; Parot, Yann; Pinet, Patrick; Schröder, Susanne; Toplis, Mike; Lewin, Éric; Brunner, Will; Heydari, Ezat; Achilles, Cherie; Oehler, Dorothy; Sutter, Brad; Cabane, Michel; Coscia, David; Israël, Guy; Szopa, Cyril; Dromart, Gilles; Robert, François; Sautter, Violaine; Le Mouélic, Stéphane; Mangold, Nicolas; Nachon, Marion; Buch, Arnaud; Stalport, Fabien; Coll, Patrice; François, Pascaline; Raulin, François; Teinturier, Samuel; Cameron, James; Clegg, Sam; Cousin, Agnès; DeLapp, Dorothea; Dingler, Robert; Jackson, Ryan Steele; Johnstone, Stephen; Lanza, Nina; Little, Cynthia; Nelson, Tony; Wiens, Roger C.; Williams, Richard B.; Jones, Andrea; Kirkland, Laurel; Treiman, Allan; Baker, Burt; Cantor, Bruce; Caplinger, Michael; Davis, Scott; Duston, Brian; Edgett, Kenneth; Fay, Donald; Hardgrove, Craig; Harker, David; Herrera, Paul; Jensen, Elsa; Kennedy, Megan R.; Krezoski, Gillian; Krysak, Daniel; Lipkaman, Leslie; Malin, Michael; McCartney, Elaina; McNair, Sean; Nixon, Brian; Posiolova, Liliya; Ravine, Michael; Salamon, Andrew; Saper, Lee; Stoiber, Kevin; Supulver, Kimberley; Van Beek, Jason; Van Beek, Tessa; Zimdar, Robert; French, Katherine Louise; Iagnemma, Karl; Miller, Kristen; Summons, Roger; Goesmann, Fred; Goetz, Walter; Hviid, Stubbe; Johnson, Micah; Lefavor, Matthew; Lyness, Eric; Breves, Elly; Dyar, M. Darby; Fassett, Caleb; Blake, David F.; Bristow, Thomas; DesMarais, David; Edwards, Laurence; Haberle, Robert; Hoehler, Tori; Hollingsworth, Jeff; Kahre, Melinda; Keely, Leslie; McKay, Christopher; Wilhelm, Mary Beth; Bleacher, Lora; Brinckerhoff, William; Choi, David; Conrad, Pamela; Dworkin, Jason P.; Eigenbrode, Jennifer; Floyd, Melissa; Freissinet, Caroline; Garvin, James; Glavin, Daniel; Harpold, Daniel; Jones, Andrea; Mahaffy, Paul; Martin, David K.; McAdam, Amy; Pavlov, Alexander; Raaen, Eric; Smith, Michael D.; Stern, Jennifer; Tan, Florence; Trainer, Melissa; Meyer, Michael; Posner, Arik; Voytek, Mary; Anderson, Robert C.; Aubrey, Andrew; Beegle, Luther W.; Behar, Alberto; Blaney, Diana; Brinza, David; Calef, Fred; Christensen, Lance; Crisp, Joy A.; DeFlores, Lauren; Ehlmann, Bethany; Feldman, Jason; Feldman, Sabrina; Flesch, Gregory; Hurowitz, Joel; Jun, Insoo; Keymeulen, Didier; Maki, Justin; Mischna, Michael; Morookian, John Michael; Parker, Timothy; Pavri, Betina; Schoppers, Marcel; Sengstacken, Aaron; Simmonds, John J.; Spanovich, Nicole; Juarez, Manuel de la Torre; Vasavada, Ashwin R.; Webster, Christopher R.; Yen, Albert; Archer, Paul Douglas; Cucinotta, Francis; Jones, John H.; Ming, Douglas; Morris, Richard V.; Niles, Paul; Rampe, Elizabeth; Nolan, Thomas; Fisk, Martin; Radziemski, Leon; Barraclough, Bruce; Bender, Steve; Berman, Daniel; Dobrea, Eldar Noe; Tokar, Robert; Vaniman, David; Williams, Rebecca M. E.; Yingst, Aileen; Lewis, Kevin; Leshin, Laurie; Cleghorn, Timothy; Huntress, Wesley; Manhès, Gérard; Hudgins, Judy; Olson, Timothy; Stewart, Noel; Sarrazin, Philippe; Grant, John; Vicenzi, Edward; Wilson, Sharon A.; Bullock, Mark; Ehresmann, Bent; Hamilton, Victoria; Hassler, Donald; Peterson, Joseph; Rafkin, Scot; Zeitlin, Cary; Fedosov, Fedor; Golovin, Dmitry; Karpushkina, Natalya; Kozyrev, Alexander; Litvak, Maxim; Malakhov, Alexey; Mitrofanov, Igor; Mokrousov, Maxim; Nikiforov, Sergey; Prokhorov, Vasily; Sanin, Anton; Tretyakov, Vladislav; Varenikov, Alexey; Vostrukhin, Andrey; Kuzmin, Ruslan; Clark, Benton; Wolff, Michael; McLennan, Scott; Botta, Oliver; Drake, Darrell; Bean, Keri; Lemmon, Mark; Schwenzer, Susanne P.; Anderson, Ryan B.; Herkenhoff, Kenneth; Lee, Ella Mae; Sucharski, Robert; Hernández, Miguel Ángel de Pablo; Ávalos, Juan José Blanco; Ramos, Miguel; Kim, Myung-Hee; Malespin, Charles; Plante, Ianik; Muller, Jan-Peter; Navarro-González, Rafael; Ewing, Ryan; Boynton, William; Downs, Robert; Fitzgibbon, Mike; Harshman, Karl; Morrison, Shaunna; Dietrich, William; Kortmann, Onno; Palucis, Marisa; Sumner, Dawn Y.; Williams, Amy; Lugmair, Günter; Wilson, Michael A.; Rubin, David; Jakosky, Bruce; Balic-Zunic, Tonci; Frydenvang, Jens; Jensen, Jaqueline Kløvgaard; Kinch, Kjartan; Koefoed, Asmus; Madsen, Morten Bo; Stipp, Susan Louise Svane; Boyd, Nick; Campbell, John L.; Gellert, Ralf; Perrett, Glynis; Pradler, Irina; VanBommel, Scott; Jacob, Samantha; Owen, Tobias; Rowland, Scott; Atlaskin, Evgeny; Savijärvi, Hannu; Boehm, Eckart; Böttcher, Stephan; Burmeister, Sönke; Guo, Jingnan; Köhler, Jan; García, César Martín; Mueller-Mellin, Reinhold; Wimmer-Schweingruber, Robert; Bridges, John C.; McConnochie, Timothy; Benna, Mehdi; Franz, Heather; Bower, Hannah; Brunner, Anna; Blau, Hannah; Boucher, Thomas; Carmosino, Marco; Atreya, Sushil; Elliott, Harvey; Halleaux, Douglas; Rennó, Nilton; Wong, Michael; Pepin, Robert; Elliott, Beverley; Spray, John; Thompson, Lucy; Gordon, Suzanne; Newsom, Horton; Ollila, Ann; Williams, Joshua; Vasconcelos, Paulo; Bentz, Jennifer; Nealson, Kenneth; Popa, Radu; Kah, Linda C.; Moersch, Jeffrey; Tate, Christopher; Day, Mackenzie; Kocurek, Gary; Hallet, Bernard; Sletten, Ronald; Francis, Raymond; McCullough, Emily; Cloutis, Ed; ten Kate, Inge Loes; Kuzmin, Ruslan; Arvidson, Raymond; Fraeman, Abigail; Scholes, Daniel; Slavney, Susan; Stein, Thomas; Ward, Jennifer; Berger, Jeffrey; Moores, John E.

    2013-10-01

    By analogy with Earth, methane in the Martian atmosphere is a potential signature of ongoing or past biological activity. During the past decade, Earth-based telescopic observations reported “plumes” of methane of tens of parts per billion by volume (ppbv), and those from Mars orbit showed localized patches, prompting speculation of sources from subsurface bacteria or nonbiological sources. From in situ measurements made with the Tunable Laser Spectrometer (TLS) on Curiosity using a distinctive spectral pattern specific to methane, we report no detection of atmospheric methane with a measured value of 0.18 ± 0.67 ppbv corresponding to an upper limit of only 1.3 ppbv (95% confidence level), which reduces the probability of current methanogenic microbial activity on Mars and limits the recent contribution from extraplanetary and geologic sources.

  20. Low upper limit to methane abundance on Mars.

    PubMed

    Webster, Christopher R; Mahaffy, Paul R; Atreya, Sushil K; Flesch, Gregory J; Farley, Kenneth A

    2013-10-18

    By analogy with Earth, methane in the Martian atmosphere is a potential signature of ongoing or past biological activity. During the past decade, Earth-based telescopic observations reported "plumes" of methane of tens of parts per billion by volume (ppbv), and those from Mars orbit showed localized patches, prompting speculation of sources from subsurface bacteria or nonbiological sources. From in situ measurements made with the Tunable Laser Spectrometer (TLS) on Curiosity using a distinctive spectral pattern specific to methane, we report no detection of atmospheric methane with a measured value of 0.18 ± 0.67 ppbv corresponding to an upper limit of only 1.3 ppbv (95% confidence level), which reduces the probability of current methanogenic microbial activity on Mars and limits the recent contribution from extraplanetary and geologic sources. PMID:24051245

  1. Geologic constraints on the upper limits of reserve growth

    USGS Publications Warehouse

    Stanley, Richard G.

    2001-01-01

    For many oil and gas fields, estimates of ultimate recovery (the sum of cumulative production plus estimated reserves) tend to increase from one year to the next, and the gain is called reserve growth. Forecasts of reserve growth by the U.S. Geological Survey rely on statistical analyses of historical records of oil and gas production and estimated reserves. The preproposal in this Open-File Report suggests that this traditional petroleum–engineering approach to reserve growth might be supplemented, or at least better understood, by using geological data from individual oil and gas fields, 3–D modeling software, and standard volumetric techniques to estimate in–place volumes of oil and gas. Such estimates, in turn, can be used to constrain the upper limits of reserve growth and ultimate recovery from those fields.

  2. An upper limit to X-ray emission from Saturn

    NASA Technical Reports Server (NTRS)

    Gilman, D. A.; Hurley, K. C.; Seward, F. D.; Schnopper, H. W.; Sullivan, J. D.; Metzger, A. E.

    1986-01-01

    X-rays are produced in auroral discharges, and their measurement can serve to characterize the interaction processes responsible for the aurora itself. The existence of auroral activity on Saturn was suggested by the observation of a magnetosphere by Pioneer 11 and confirmed by UV measurements during the Voyager encounters. The detection of X-rays from Jupiter with the Einstein Observatory (HEAO 2) satellite provided the impetus for a subsequent observation of Saturn. No emission was detected. This article presents the upper limit established by the observation and derives an expected emission level assuming X-ray production to be the result of bremsstrahlung from keV electrons precipitating into Saturn's atmosphere. The difference is a factor of 100.

  3. Pulsation, Mass Loss and the Upper Mass Limit

    NASA Astrophysics Data System (ADS)

    Klapp, J.; Corona-Galindo, M. G.

    1990-11-01

    RESUMEN. La existencia de estrellas con masas en exceso de 100 M0 ha sido cuestionada por mucho tiempo. Lfmites superiores para la masa de 100 M0 han sido obtenidos de teorfas de pulsaci6n y formaci6n estelar. En este trabajo nosotros primero investigamos la estabilidad radial de estrellas masivas utilizando la aproximaci6n clasica cuasiadiabatica de Ledoux, la aproximaci6n cuasiadiabatica de Castor y un calculo completamente no-adiabatico. Hemos encontrado que los tres metodos de calculo dan resultados similares siempre y cuando una pequefia regi6n de las capas externas de la estrella sea despreciada para la aproximaci6n clasica. La masa crftica para estabilidad de estrellas masivas ha sido encontrada en acuerdo a trabajos anteriores. Explicamos Ia discrepancia entre este y trabajos anteriores por uno de los autores. Discunmos calculos no-lineales y perdida de masa con respecto a) lfmite superior de masa. The existence of stars with masses in excess of 100 M0 has been questioned for a very long time. Upper mass limits of 100 Me have been obtained from pulsation and star formation theories. In this work we first investigate the radial stability of massive stars using the classical Ledoux's quasiadiabatic approximation. the Castor quasiadiabatic approximation and a fully nonadiabatic calculation. We have found that the three methods of calculation give similar results provided that a small region in outer layers of the star be neglected for the classical approximation. The critical mass for stability of massive stars is found to be in agreement with previous work. We explain the reason for the discrepancy between this and previous work by one of the authors. We discuss non-linear calculations and mass loss with regard to the upper mass limit. Key words: STARS-MASS FUNCTION - STARS-MASS LOSS - STARS-PULSATION

  4. Placing an upper limit on cryptic marine sulphur cycling

    NASA Astrophysics Data System (ADS)

    Johnston, D. T.; Gill, B. C.; Masterson, A.; Beirne, E.; Casciotti, K. L.; Knapp, A. N.; Berelson, W.

    2014-09-01

    A quantitative understanding of sources and sinks of fixed nitrogen in low-oxygen waters is required to explain the role of oxygen-minimum zones (OMZs) in controlling the fixed nitrogen inventory of the global ocean. Apparent imbalances in geochemical nitrogen budgets have spurred numerous studies to measure the contributions of heterotrophic and autotrophic N2-producing metabolisms (denitrification and anaerobic ammonia oxidation, respectively). Recently, `cryptic' sulphur cycling was proposed as a partial solution to the fundamental biogeochemical problem of closing marine fixed-nitrogen budgets in intensely oxygen-deficient regions. The degree to which the cryptic sulphur cycle can fuel a loss of fixed nitrogen in the modern ocean requires the quantification of sulphur recycling in OMZ settings. Here we provide a new constraint for OMZ sulphate reduction based on isotopic profiles of oxygen (18O/16O) and sulphur (33S/32S, 34S/32S) in seawater sulphate through oxygenated open-ocean and OMZ-bearing water columns. When coupled with observations and models of sulphate isotope dynamics and data-constrained model estimates of OMZ water-mass residence time, we find that previous estimates for sulphur-driven remineralization and loss of fixed nitrogen from the oceans are near the upper limit for what is possible given in situ sulphate isotope data.

  5. Placing an upper limit on cryptic marine sulphur cycling.

    PubMed

    Johnston, D T; Gill, B C; Masterson, A; Beirne, E; Casciotti, K L; Knapp, A N; Berelson, W

    2014-09-25

    A quantitative understanding of sources and sinks of fixed nitrogen in low-oxygen waters is required to explain the role of oxygen-minimum zones (OMZs) in controlling the fixed nitrogen inventory of the global ocean. Apparent imbalances in geochemical nitrogen budgets have spurred numerous studies to measure the contributions of heterotrophic and autotrophic N2-producing metabolisms (denitrification and anaerobic ammonia oxidation, respectively). Recently, 'cryptic' sulphur cycling was proposed as a partial solution to the fundamental biogeochemical problem of closing marine fixed-nitrogen budgets in intensely oxygen-deficient regions. The degree to which the cryptic sulphur cycle can fuel a loss of fixed nitrogen in the modern ocean requires the quantification of sulphur recycling in OMZ settings. Here we provide a new constraint for OMZ sulphate reduction based on isotopic profiles of oxygen ((18)O/(16)O) and sulphur ((33)S/(32)S, (34)S/(32)S) in seawater sulphate through oxygenated open-ocean and OMZ-bearing water columns. When coupled with observations and models of sulphate isotope dynamics and data-constrained model estimates of OMZ water-mass residence time, we find that previous estimates for sulphur-driven remineralization and loss of fixed nitrogen from the oceans are near the upper limit for what is possible given in situ sulphate isotope data. PMID:25209667

  6. Placing an upper limit on cryptic marine sulphur cycling.

    PubMed

    Johnston, D T; Gill, B C; Masterson, A; Beirne, E; Casciotti, K L; Knapp, A N; Berelson, W

    2014-09-25

    A quantitative understanding of sources and sinks of fixed nitrogen in low-oxygen waters is required to explain the role of oxygen-minimum zones (OMZs) in controlling the fixed nitrogen inventory of the global ocean. Apparent imbalances in geochemical nitrogen budgets have spurred numerous studies to measure the contributions of heterotrophic and autotrophic N2-producing metabolisms (denitrification and anaerobic ammonia oxidation, respectively). Recently, 'cryptic' sulphur cycling was proposed as a partial solution to the fundamental biogeochemical problem of closing marine fixed-nitrogen budgets in intensely oxygen-deficient regions. The degree to which the cryptic sulphur cycle can fuel a loss of fixed nitrogen in the modern ocean requires the quantification of sulphur recycling in OMZ settings. Here we provide a new constraint for OMZ sulphate reduction based on isotopic profiles of oxygen ((18)O/(16)O) and sulphur ((33)S/(32)S, (34)S/(32)S) in seawater sulphate through oxygenated open-ocean and OMZ-bearing water columns. When coupled with observations and models of sulphate isotope dynamics and data-constrained model estimates of OMZ water-mass residence time, we find that previous estimates for sulphur-driven remineralization and loss of fixed nitrogen from the oceans are near the upper limit for what is possible given in situ sulphate isotope data.

  7. Upper limits to the nightside ionosphere of Mars

    NASA Technical Reports Server (NTRS)

    Fox, J. L.; Brannon, J. F.; Porter, H. S.

    1993-01-01

    The nightside ionosphere of Mars could be produced by electron precipitation or by plasma transport from the dayside, by analogy to the Venus, but few measurements are available. We report here model calculations of upper limits to the nightside ion densities on Mars that would be produced by both mechanisms. For the auroral model, we have adopted the downward traveling portions of the electron spectra measured by the HARP instrument on the Soviet Phobos spacecraft in the Martian plasma sheet and in the magnetotail lobes. For the plasma transport case, we have imposed on a model of the nightside thermosphere, downward fluxes of O(+), C(+), N(+), NO(+) and O2(+) that are near the maximum upward fluxes that can be sustained by the dayside ionosphere. The computed electron density peaks are in the range (1.3 - 1.9) x 10 exp 4/cu cm at altitudes of 159 to 179 kin. The major ion for all the models is O2(+), but significant differences in the composition of the minor ions are found for the ionospheres produced by auroral precipitation and by plasma transport. The calculations reported here provide a guide to the data that should be acquired during a future aeronomy mission to Mars, in order to determine the sources of the nightside ionosphere.

  8. Upper limits to the nightside ionosphere of Mars

    NASA Astrophysics Data System (ADS)

    Fox, J. L.; Brannon, J. F.; Porter, H. S.

    1993-07-01

    The nightside ionosphere of Mars could be produced by electron precipitation or by plasma transport from the dayside, by analogy to the Venus, but few measurements are available. We report here model calculations of upper limits to the nightside ion densities on Mars that would be produced by both mechanisms. For the auroral model, we have adopted the downward traveling portions of the electron spectra measured by the HARP instrument on the Soviet Phobos spacecraft in the Martian plasma sheet and in the magnetotail lobes. For the plasma transport case, we have imposed on a model of the nightside thermosphere, downward fluxes of O(+), C(+), N(+), NO(+) and O2(+) that are near the maximum upward fluxes that can be sustained by the dayside ionosphere. The computed electron density peaks are in the range (1.3 - 1.9) x 10 exp 4/cu cm at altitudes of 159 to 179 kin. The major ion for all the models is O2(+), but significant differences in the composition of the minor ions are found for the ionospheres produced by auroral precipitation and by plasma transport. The calculations reported here provide a guide to the data that should be acquired during a future aeronomy mission to Mars, in order to determine the sources of the nightside ionosphere.

  9. Upper Limits of Predictability in Long-Range Climate/Hydrologic Forecasts

    NASA Technical Reports Server (NTRS)

    Koster, R. D.; Suarez, M. J.; Heiser, M.

    1998-01-01

    The accurate forecasting of el nino or la nina conditions in the tropical Pacific can potentially lead to valuable predictions of hydrological anomalies over land at seasonal to interannual timescales. Even with highly accurate earth system models, though, our ability to generate these continental forecasts will always be limited by the chaotic nature of the atmospheric circulation. The nature of this fundamental limitation is explored through the use of 16-member ensembles of multi-decade GCM simulations. In each simulation of the first ensemble, sea surface temperatures (SSTs) are given the same realistic interannual variations over a 45-year period, and land surface state is allowed to evolve with that of the atmosphere. Analysis of the results shows that the SSTs control the temporal organization of continental precipitation anomalies to a significant extent in the tropics and to a much smaller extent in midlatitudes. In each simulation of the second ensemble, we prescribe SSTs as before, but we also prescribe interannual variations in the low frequency component of evaporation efficiency over land. Thus, in the second ensemble, we effectively make the extreme assumption that surface boundary conditions across the globe are perfectly predictable, and we quantify the consistency with which the atmosphere (particularly precipitation) responds to these boundary conditions. The resulting "absolute upper limit" on the predictability of precipitation is found to be quite high in the tropics yet only moderate in many midlatitude regions.

  10. 42 CFR 447.514 - Upper limits for multiple source drugs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Upper limits for multiple source drugs. 447.514... limits for multiple source drugs. (a) Establishment and issuance of a listing. (1) CMS will establish and issue listings that identify and set upper limits for multiple source drugs that meet the...

  11. Upper limits on the total cosmic-ray luminosity of individual sources

    SciTech Connect

    Anjos, R.C.; De Souza, V.; Supanitsky, A.D. E-mail: vitor@ifsc.usp.br

    2014-07-01

    In this paper, upper limits on the total luminosity of ultra-high-energy cosmic-rays (UHECR) E > 10{sup 18} eV) are determined for five individual sources. The upper limit on the integral flux of GeV--TeV gamma-rays is used to extract the upper limit on the total UHECR luminosity of individual sources. The correlation between upper limit on the integral GeV--TeV gamma-ray flux and upper limit on the UHECR luminosity is established through the cascading process that takes place during propagation of the cosmic rays in the background radiation fields, as explained in reference [1]. Twenty-eight sources measured by FERMI-LAT, VERITAS and MAGIC observatories have been studied. The measured upper limit on the GeV--TeV gamma-ray flux is restrictive enough to allow the calculation of an upper limit on the total UHECR cosmic-ray luminosity of five sources. The upper limit on the UHECR cosmic-ray luminosity of these sources is shown for several assumptions on the emission mechanism. For all studied sources an upper limit on the ultra-high-energy proton luminosity is also set.

  12. An upper limit to the product of NO and O densities from 105 to 120 km

    NASA Technical Reports Server (NTRS)

    Donahue, T. M.

    1974-01-01

    From the Ogo 6 horizon-scanning-photometer data a useful upper limit can be set to the radiance of nightglow in the O-NO afterglow continuum above 105 km. The upper limit is a factor of about 5 less than the product of observed NO densities and Jacchia (1971) O model densities.

  13. 42 CFR 447.512 - Drugs: Aggregate upper limits of payment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...: Aggregate upper limits of payment. (a) (b) Other drugs. The agency payments for brand name drugs certified... of brand name drugs. (1) The upper limit for payment for multiple source drugs for which a specific... an electronic alternative means approved by the Secretary) that a specific brand is...

  14. 42 CFR 447.512 - Drugs: Aggregate upper limits of payment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Drugs: Aggregate upper limits of payment. 447.512 Section 447.512 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS PAYMENTS FOR SERVICES Payment for Drugs § 447.512 Drugs: Aggregate upper limits of payment....

  15. 42 CFR 447.516 - Upper limits for drugs furnished as part of services.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Upper limits for drugs furnished as part of services. 447.516 Section 447.516 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS PAYMENTS FOR SERVICES Payment for Drugs § 447.516 Upper limits for drugs furnished...

  16. A retrieved upper limit of CS in Neptune's atmosphere

    NASA Astrophysics Data System (ADS)

    Iino, T.; Mizuno, A.; Nagahama, T.; Hirota, A.; Nakajima, T.

    2012-12-01

    We present our new result of CS(J=7-6), CO(J=3-2) observations of Neptune's atmosphere carried out with 10-m ASTE sub-mm waveband telescope on August 2010. As a result, while CS line was not detected with 6.4 mK 1-sigma r.m.s. noise level, CO line was detected as 282 mK with 9.7 mK noise level in antenna temperature scale. All of the observations were carried out with 512 MHz bandwidth and 500 kHz resolution, the total integration time for CS and CO were 23 m 40 s and 11 m 00 s, respectively. Abundances have been obtained from the comparison between the intensity and the synthesis spectra modeled by plane parallel 1-D radiative transfer code assuming various mixing ratio of each gas. The retrieved upper limit of CS mixing ratio was 0.03 ppb throughout tropopause to stratosphere. CO mixing ratio have been retrieved 1.0 ppm with errors +0.3 and -0.2 ppm, and the result was consistent with previous observation [1]. The origin of abundant CO in Neptune's atmosphere has been long discussed since its mixing ratio is 30 - 500 times higher than the value of other gas giants [2][3][4]. Assuming that all of CO is produced by thermochemical equilibrium process in deep interior of Neptune, required O/H value in interior is 440 times higher than the solar value [5]. For this reason, it is claimed that the external CO supply source, such as the impact of comet or asteroid, is also the possible candidates of the origin of CO along with the internal supply source [6]. In this observation, we searched the remnant gas of cometary impact in Neptune's atmosphere. Along with CO and HCN, CS could be one of the possible candidate of the remnant gas of cometary impact since CS was largely produced after the impact of comet SL/9 on Jupiter while many other major sulfur compounds have not been detected. Actually, derived < 0.00003 [CS]/[CO] value from our observations is 1000 times more smaller than the value of Jupiter of 0.037 [7]. Our observation result shows the depletion of CS in

  17. Estimation of upper flammability limits of C-H compounds in air at standard atmospheric pressure and evaluation of temperature dependence.

    PubMed

    Mendiburu, Andrés Z; de Carvalho, João A; Coronado, Christian R

    2016-03-01

    This study focuses on estimating the upper flammability limits of C-H compounds. A method was developed to determine the upper flammability limits in air at standard atmospheric pressure for the following cases: (a) estimation of the UFLs of pure C-H compounds at standard ambient temperature (25°C); (b) estimation of the UFLs of binary mixtures of C-H compounds at standard ambient temperature (25°C); (c) estimation of the UFLs of C-H compounds at different initial temperatures. The method was accurate in all cases. In case (a), for a total set of 115 compounds, the absolute average relative error was 7.27% and a squared correlation coefficient of 0.9248 was obtained. In case (b), the average absolute relative error was 5.55%; in case (c) it was 2.19%. PMID:26619050

  18. Estimation of upper flammability limits of C-H compounds in air at standard atmospheric pressure and evaluation of temperature dependence.

    PubMed

    Mendiburu, Andrés Z; de Carvalho, João A; Coronado, Christian R

    2016-03-01

    This study focuses on estimating the upper flammability limits of C-H compounds. A method was developed to determine the upper flammability limits in air at standard atmospheric pressure for the following cases: (a) estimation of the UFLs of pure C-H compounds at standard ambient temperature (25°C); (b) estimation of the UFLs of binary mixtures of C-H compounds at standard ambient temperature (25°C); (c) estimation of the UFLs of C-H compounds at different initial temperatures. The method was accurate in all cases. In case (a), for a total set of 115 compounds, the absolute average relative error was 7.27% and a squared correlation coefficient of 0.9248 was obtained. In case (b), the average absolute relative error was 5.55%; in case (c) it was 2.19%.

  19. Stratigraphy, structure, absolute age, and paleontology of the upper Pleistocene deposits at Sankaty Head, Nantucket Island, Massachusetts

    USGS Publications Warehouse

    Oldale, Robert N.; Valentine, Page C.; Cronin, T. M.; Spiker, E. C.; Blackwelder, B. W.; Belknap, D.F.; Wehmiller, J. F.; Szabo, B. J.

    1982-01-01

    The Sankaty Head cliff exposes drift of at least two glaciations and interglacial marine deposits. Radiocarbon, amino-acid- racemization, and uranium-thorium analyses were used to determine the absolute ages of the beds. The results indicate that 1) the Sankaty Sand correlates with oxygen-isotope stage 5 (Sangamonian), 2) the underlying drift is older than stage 5 (Illinoian or older) , and 3) the overlying drift is Wisconsinan in age. -from Authors

  20. Gardening in the zone of death: an experimental assessment of the absolute elevation limit of vascular plants

    PubMed Central

    Dvorský, Miroslav; Chlumská, Zuzana; Altman, Jan; Čapková, Kateřina; Řeháková, Klára; Macek, Martin; Kopecký, Martin; Liancourt, Pierre; Doležal, Jiří

    2016-01-01

    Vascular plants in the western Tibetan Plateau reach 6000 m-the highest elevation on Earth. Due to the significant warming of the region, plant ranges are expected to shift upwards. However, factors governing maximum elevational limits of plant are unclear. To experimentally assess these factors, we transplanted 12 species from 5750 m to 5900 m (upper edge of vegetation) and 6100 m (beyond range) and monitored their survival for six years. In the first three years (2009–2012), there were plants surviving beyond the regional upper limit of vegetation. This supports the hypothesis of dispersal and/or recruitment limitation. Substantial warming, recorded in-situ during this period, very likely facilitated the survival. The survival was ecologically a non-random process, species better adapted to repeated soil freezing and thawing survived significantly better. No species have survived at 6100 m since 2013, probably due to the extreme snowfall in 2013. In conclusion, apart from the minimum heat requirements, our results show that episodic climatic events are decisive determinants of upper elevational limits of vascular plants. PMID:27071305

  1. Gardening in the zone of death: an experimental assessment of the absolute elevation limit of vascular plants.

    PubMed

    Dvorský, Miroslav; Chlumská, Zuzana; Altman, Jan; Čapková, Kateřina; Řeháková, Klára; Macek, Martin; Kopecký, Martin; Liancourt, Pierre; Doležal, Jiří

    2016-01-01

    Vascular plants in the western Tibetan Plateau reach 6000 m--the highest elevation on Earth. Due to the significant warming of the region, plant ranges are expected to shift upwards. However, factors governing maximum elevational limits of plant are unclear. To experimentally assess these factors, we transplanted 12 species from 5750 m to 5900 m (upper edge of vegetation) and 6100 m (beyond range) and monitored their survival for six years. In the first three years (2009-2012), there were plants surviving beyond the regional upper limit of vegetation. This supports the hypothesis of dispersal and/or recruitment limitation. Substantial warming, recorded in-situ during this period, very likely facilitated the survival. The survival was ecologically a non-random process, species better adapted to repeated soil freezing and thawing survived significantly better. No species have survived at 6100 m since 2013, probably due to the extreme snowfall in 2013. In conclusion, apart from the minimum heat requirements, our results show that episodic climatic events are decisive determinants of upper elevational limits of vascular plants. PMID:27071305

  2. Gardening in the zone of death: an experimental assessment of the absolute elevation limit of vascular plants.

    PubMed

    Dvorský, Miroslav; Chlumská, Zuzana; Altman, Jan; Čapková, Kateřina; Řeháková, Klára; Macek, Martin; Kopecký, Martin; Liancourt, Pierre; Doležal, Jiří

    2016-04-13

    Vascular plants in the western Tibetan Plateau reach 6000 m--the highest elevation on Earth. Due to the significant warming of the region, plant ranges are expected to shift upwards. However, factors governing maximum elevational limits of plant are unclear. To experimentally assess these factors, we transplanted 12 species from 5750 m to 5900 m (upper edge of vegetation) and 6100 m (beyond range) and monitored their survival for six years. In the first three years (2009-2012), there were plants surviving beyond the regional upper limit of vegetation. This supports the hypothesis of dispersal and/or recruitment limitation. Substantial warming, recorded in-situ during this period, very likely facilitated the survival. The survival was ecologically a non-random process, species better adapted to repeated soil freezing and thawing survived significantly better. No species have survived at 6100 m since 2013, probably due to the extreme snowfall in 2013. In conclusion, apart from the minimum heat requirements, our results show that episodic climatic events are decisive determinants of upper elevational limits of vascular plants.

  3. Bounded Rationality and Cognitive Development: Upper Limits on Growth?

    ERIC Educational Resources Information Center

    Shaklee, Harriet

    1979-01-01

    Piaget's characterization of formal operational thought and human judgment psychologists' model of bounded rationality are two conflicting models dealing with the nature and limits of mature thought. However, a look at the respective databases demonstrates their complementarity and their contribution to understanding mature cognition. (Author/RD)

  4. Measuring absolute frequencies beyond the GPS limit via long-haul optical frequency dissemination.

    PubMed

    Clivati, Cecilia; Cappellini, Giacomo; Livi, Lorenzo F; Poggiali, Francesco; de Cumis, Mario Siciliani; Mancini, Marco; Pagano, Guido; Frittelli, Matteo; Mura, Alberto; Costanzo, Giovanni A; Levi, Filippo; Calonico, Davide; Fallani, Leonardo; Catani, Jacopo; Inguscio, Massimo

    2016-05-30

    Global Positioning System (GPS) dissemination of frequency standards is ubiquitous at present, providing the most widespread time and frequency reference for the majority of industrial and research applications worldwide. On the other hand, the ultimate limits of the GPS presently curb further advances in high-precision, scientific and industrial applications relying on this dissemination scheme. Here, we demonstrate that these limits can be reliably overcome even in laboratories without a local atomic clock by replacing the GPS with a 642-km-long optical fiber link to a remote primary caesium frequency standard. Through this configuration we stably address the 1S0-3P0 clock transition in an ultracold gas of 173Yb, with a precision that exceeds the possibilities of a GPS-based measurement, dismissing the need for a local clock infrastructure to perform beyond-GPS high-precision tasks. We also report an improvement of two orders of magnitude in the accuracy on the transition frequency reported in literature. PMID:27410109

  5. Measuring absolute frequencies beyond the GPS limit via long-haul optical frequency dissemination.

    PubMed

    Clivati, Cecilia; Cappellini, Giacomo; Livi, Lorenzo F; Poggiali, Francesco; de Cumis, Mario Siciliani; Mancini, Marco; Pagano, Guido; Frittelli, Matteo; Mura, Alberto; Costanzo, Giovanni A; Levi, Filippo; Calonico, Davide; Fallani, Leonardo; Catani, Jacopo; Inguscio, Massimo

    2016-05-30

    Global Positioning System (GPS) dissemination of frequency standards is ubiquitous at present, providing the most widespread time and frequency reference for the majority of industrial and research applications worldwide. On the other hand, the ultimate limits of the GPS presently curb further advances in high-precision, scientific and industrial applications relying on this dissemination scheme. Here, we demonstrate that these limits can be reliably overcome even in laboratories without a local atomic clock by replacing the GPS with a 642-km-long optical fiber link to a remote primary caesium frequency standard. Through this configuration we stably address the 1S0-3P0 clock transition in an ultracold gas of 173Yb, with a precision that exceeds the possibilities of a GPS-based measurement, dismissing the need for a local clock infrastructure to perform beyond-GPS high-precision tasks. We also report an improvement of two orders of magnitude in the accuracy on the transition frequency reported in literature.

  6. New upper limit on strange quark matter flux with PAMELA space experiment

    NASA Astrophysics Data System (ADS)

    Casolino, Marco

    We present an upper limit for search of Strange Quark Matter (SQM) in cosmic rays with PAMELA experiment. These hypothetical particles could be detected as nuclei having high and anomalous mass/charge (A=Z) ratio, exhibiting a low velocity in the PAMELA Time-of-Flight ystem and an high rigidity in the magnetic spectrometer. We will discuss upper limits in terms of normal/strange matter for Z=1,2 up to 8. Furthermore PAMELA can provide an upper limit covering the mass range 10 < A < 10E5, with charge 1 <= Z <= 8 and rigidity 0.4 <= R <= 1200 GV. The upper limit here obtained is complementary in range and region probed with those coming from ground based spectrometers and could constrain some astrophysical production models of SQM.

  7. Multivariate analysis of adaptive capacity for upper thermal limits in Drosophila simulans.

    PubMed

    van Heerwaarden, B; Sgrò, C M

    2013-04-01

    Thermal tolerance is an important factor influencing the distribution of ectotherms, but our understanding of the ability of species to evolve different thermal limits is limited. Based on univariate measures of adaptive capacity, it has recently been suggested that species may have limited evolutionary potential to extend their upper thermal limits under ramping temperature conditions that better reflect heat stress in nature. To test these findings more broadly, we used a paternal half-sibling breeding design to estimate the multivariate evolutionary potential for upper thermal limits in Drosophila simulans. We assessed heat tolerance using static (basal and hardened) and ramping assays. Our analyses revealed significant evolutionary potential for all three measures of heat tolerance. Additive genetic variances were significantly different from zero for all three traits. Our G matrix analysis revealed that all three traits would contribute to a response to selection for increased heat tolerance. Significant additive genetic covariances and additive genetic correlations between static basal and hardened heat-knockdown time, marginally nonsignificant between static basal and ramping heat-knockdown time, indicate that direct and correlated responses to selection for increased upper thermal limits are possible. Thus, combinations of all three traits will contribute to the evolution of upper thermal limits in response to selection imposed by a warming climate. Reliance on univariate estimates of evolutionary potential may not provide accurate insight into the ability of organisms to evolve upper thermal limits in nature.

  8. Probability of Future Observations Exceeding One-Sided, Normal, Upper Tolerance Limits

    DOE PAGES

    Edwards, Timothy S.

    2014-10-29

    Normal tolerance limits are frequently used in dynamic environments specifications of aerospace systems as a method to account for aleatory variability in the environments. Upper tolerance limits, when used in this way, are computed from records of the environment and used to enforce conservatism in the specification by describing upper extreme values the environment may take in the future. Components and systems are designed to withstand these extreme loads to ensure they do not fail under normal use conditions. The degree of conservatism in the upper tolerance limits is controlled by specifying the coverage and confidence level (usually written inmore » “coverage/confidence” form). Moreover, in high-consequence systems it is common to specify tolerance limits at 95% or 99% coverage and confidence at the 50% or 90% level. Despite the ubiquity of upper tolerance limits in the aerospace community, analysts and decision-makers frequently misinterpret their meaning. The misinterpretation extends into the standards that govern much of the acceptance and qualification of commercial and government aerospace systems. As a result, the risk of a future observation of the environment exceeding the upper tolerance limit is sometimes significantly underestimated by decision makers. This note explains the meaning of upper tolerance limits and a related measure, the upper prediction limit. So, the objective of this work is to clarify the probability of exceeding these limits in flight so that decision-makers can better understand the risk associated with exceeding design and test levels during flight and balance the cost of design and development with that of mission failure.« less

  9. Probability of Future Observations Exceeding One-Sided, Normal, Upper Tolerance Limits

    SciTech Connect

    Edwards, Timothy S.

    2014-10-29

    Normal tolerance limits are frequently used in dynamic environments specifications of aerospace systems as a method to account for aleatory variability in the environments. Upper tolerance limits, when used in this way, are computed from records of the environment and used to enforce conservatism in the specification by describing upper extreme values the environment may take in the future. Components and systems are designed to withstand these extreme loads to ensure they do not fail under normal use conditions. The degree of conservatism in the upper tolerance limits is controlled by specifying the coverage and confidence level (usually written in “coverage/confidence” form). Moreover, in high-consequence systems it is common to specify tolerance limits at 95% or 99% coverage and confidence at the 50% or 90% level. Despite the ubiquity of upper tolerance limits in the aerospace community, analysts and decision-makers frequently misinterpret their meaning. The misinterpretation extends into the standards that govern much of the acceptance and qualification of commercial and government aerospace systems. As a result, the risk of a future observation of the environment exceeding the upper tolerance limit is sometimes significantly underestimated by decision makers. This note explains the meaning of upper tolerance limits and a related measure, the upper prediction limit. So, the objective of this work is to clarify the probability of exceeding these limits in flight so that decision-makers can better understand the risk associated with exceeding design and test levels during flight and balance the cost of design and development with that of mission failure.

  10. Easy Absolute Values? Absolutely

    ERIC Educational Resources Information Center

    Taylor, Sharon E.; Mittag, Kathleen Cage

    2015-01-01

    The authors teach a problem-solving course for preservice middle-grades education majors that includes concepts dealing with absolute-value computations, equations, and inequalities. Many of these students like mathematics and plan to teach it, so they are adept at symbolic manipulations. Getting them to think differently about a concept that they…

  11. Modelling reference conditions for the upper limit of Posidonia oceanica meadows: a morphodynamic approach

    NASA Astrophysics Data System (ADS)

    Vacchi, Matteo; Misson, Gloria; Montefalcone, Monica; Archetti, Renata; Nike Bianchi, Carlo; Ferrari, Marco

    2014-05-01

    The upper portion of the meadows of the protected Mediterranean seagrass Posidonia oceanica occurs in the region of the seafloor mostly affected by surf-related effects. Evaluation of its status is part of monitoring programs, but proper conclusions are difficult to draw due to the lack of definite reference conditions. Comparing the position of the meadow upper limit with the beach morphodynamics (i.e. the distinctive type of beach produced by topography and wave climate) provided evidence that the natural landwards extension of meadows can be predicted. Here we present an innovative predictive cartographic approach able to identify the seafloor portion where the meadow upper limit should naturally lies (i.e. its reference conditions). The conceptual framework of this model is based on 3 essential components: i) Definition of the breaking depth geometry: the breaking limit represents the major constrain for the landward meadow development. We modelled the breaking limit (1 year return time) using the software Mike 21 sw. ii) Definition of the morphodynamic domain of the beach using the surf scaling index ɛ; iii) Definition of the P. oceanica upper limit geometry. We coupled detailed aerial photo with thematic bionomic cartography. In GIS environment, we modelled the seafloor extent where the meadow should naturally lies according to the breaking limit position and the morphodynamic domain of the beach. Then, we added the GIS layer with the meadow upper limit geometry. Therefore, the final output shows, on the same map, both the reference condition and the actual location of the upper limit. It make possible to assess the status of the landward extent of a given P. oceanica meadow and quantify any suspected or observed regression caused by anthropic factors. The model was elaborated and validated along the Ligurian coastline (NW Mediteraanean) and was positively tested in other Mediterranean areas.

  12. The relationship between the Eddington limit, the observed upper luminosity limit for massive stars, and the luminous blue variables

    NASA Technical Reports Server (NTRS)

    Lamers, Henny J. G. L. M.; Fitzpatrick, Edward L.

    1988-01-01

    The observed upper luminosity limits in the Galaxy and the LMC are compared with the Eddington limit as estimated for plane-parallel LTE model atmospheres which include the full effects of metal line opacities in the ultraviolet. It is shown that the Humphreys-Davidson (HD) limit corresponds to the locus of extremely low effective gravities. This result suggests that stars approaching the HD limit will suffer high mass-loss rates because of the reduction of the effective gravity due to radiation pressure. These high mass-loss rates ultimtely lead to the core mass fraction reaching its critical value and the reversal of the stellar evolution tracks. It is shown that radiation pressure, as an agent for producing enhanced mass loss near the HD limit, can in a natural way explain the kink in the HD limit near T(eff) roughly 10,000 K and the upper luminosity limit for yellow and red supergiants. The high mass-loss rates of the luminous blue variables, their location in the HR diagram, and their evolutionary stage are also discussed.

  13. Upper limits on the cosmological gravitational wave background and maser clocks in space

    NASA Astrophysics Data System (ADS)

    Polnarev, A. G.; Roxburgh, I. W.

    1995-04-01

    We consider the possibility of detecting gravitational waves through the measurement of a time varying phase shift using a hydrogen maser clock on a satellite. Such measurements enable us to put interesting upper limits on the contribution of the gravitational-wave background to the dimensionless density of the Universe. The requirements on residual accelerations and the sensitivity of an accelerometer on the spacecraft are shown to be realistic and could be achieved using the accelerometer technology developed by ONERA for the ARISTOTELES mission. Such an experiment placing upper limits on the cosmological gravitational wave background could be conducted using the proposed Russian satellite “Millimetron”.

  14. Upper limits for X-ray emission from Jupiter as measured from the Copernicus satellite

    NASA Technical Reports Server (NTRS)

    Vesecky, J. F.; Culhane, J. L.; Hawkins, F. J.

    1975-01-01

    X-ray telescopic observations are made by the Copernicus satellite for detecting X-ray emission from Jupiter analogous to X-rays from terrestrial aurorae. Values of X-ray fluxes recorded by three Copernicus detectors covering the 0.6 to 7.5 keV energy range are reported. The detectors employed are described and the times at which the observations were made are given. Resulting upper-limit spectra are compared with previous X-ray observations of Jupiter. The upper-limit X-ray fluxes are discussed in terms of magnetospheric activity on Jupiter.

  15. Upper limits on extreme ultraviolet radiation from nearby main sequence and subgiant stars

    NASA Technical Reports Server (NTRS)

    Ayres, T. R.; Linsky, J. L.; Margon, B.; Bowyer, S.

    1978-01-01

    Flux upper limits for 44-800 A radiation were measured in a sample of nearby main sequence stars and one subgiant star with the aid of the Apollo-Soyuz grazing incidence telescope. Comparisons of emission measure upper limits with three different methods for predicting coronal properties cannot yet determine which, if any, are valid. Data for Alpha Centauri A and B are consistent with recent HEAO-1 soft X-ray measurements which suggest that the surface flux of coronal emission from the Alpha Cen system is comparable to that of the 'normal' sun.

  16. A New PROS Task for Calculating HRI Source Intensities or Upper Limits

    NASA Astrophysics Data System (ADS)

    Chen, J. C.; Conroy, M. A.; Deponte, J.; Primini, F. A.

    The srcinten task provides PROS users with a tool to compute count rates for point sources in the ROSAT High Resolution Imager (HRI). Count rates are corrected for point response function, vignetting, and quantum efficiency effects. Corrected upper limits are cited at locations where the count rate falls below the source detection threshold.

  17. 42 CFR 447.325 - Other inpatient and outpatient facility services: Upper limits of payment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Other inpatient and outpatient facility services... Methods for Other Institutional and Noninstitutional Services Other Inpatient and Outpatient Facilities § 447.325 Other inpatient and outpatient facility services: Upper limits of payment. The agency may...

  18. An upper limit to the interstellar abundance of the HCN dimer

    NASA Technical Reports Server (NTRS)

    Storey, J. W. V.; Cheung, A. C.

    1978-01-01

    An unsuccessful search is described for the J = 7-6 transition of HCN ... HCN in several interstellar clouds known to be rich in HCN. An upper limit to the abundance of the dimer relative to the monomer is typically 1 percent. It is suggested that this implies a low abundance for similar weakly bound species.

  19. Upper limit on the inner radiation belt MeV electron intensity

    PubMed Central

    Li, X; Selesnick, RS; Baker, DN; Jaynes, AN; Kanekal, SG; Schiller, Q; Blum, L; Fennell, J; Blake, JB

    2015-01-01

    No instruments in the inner radiation belt are immune from the unforgiving penetration of the highly energetic protons (tens of MeV to GeV). The inner belt proton flux level, however, is relatively stable; thus, for any given instrument, the proton contamination often leads to a certain background noise. Measurements from the Relativistic Electron and Proton Telescope integrated little experiment on board Colorado Student Space Weather Experiment CubeSat, in a low Earth orbit, clearly demonstrate that there exist sub-MeV electrons in the inner belt because their flux level is orders of magnitude higher than the background, while higher-energy electron (>1.6 MeV) measurements cannot be distinguished from the background. Detailed analysis of high-quality measurements from the Relativistic Electron and Proton Telescope on board Van Allen Probes, in a geo-transfer-like orbit, provides, for the first time, quantified upper limits on MeV electron fluxes in various energy ranges in the inner belt. These upper limits are rather different from flux levels in the AE8 and AE9 models, which were developed based on older data sources. For 1.7, 2.5, and 3.3 MeV electrons, the upper limits are about 1 order of magnitude lower than predicted model fluxes. The implication of this difference is profound in that unless there are extreme solar wind conditions, which have not happened yet since the launch of Van Allen Probes, significant enhancements of MeV electrons do not occur in the inner belt even though such enhancements are commonly seen in the outer belt. Key Points Quantified upper limit of MeV electrons in the inner belt Actual MeV electron intensity likely much lower than the upper limit More detailed understanding of relativistic electrons in the magnetosphere PMID:26167446

  20. An upper limit to ground state energy fluctuations in nuclear masses

    SciTech Connect

    Hirsch, Jorge G.; Frank, Alejandro; Barea, Jose; Velazquez, Victor; Isacker, Piet van; Zuker, Andres P.

    2007-02-12

    Shell model calculations are employed to estimate un upper limit of statistical fluctuations in the nuclear ground state energies. In order to mimic the presence of quantum chaos associated with neutron resonances at energies between 6 to 10 MeV, calculations include random interactions in the upper shells. The upper bound for the energy fluctuations at mid-shell is shown to have the form {sigma}(A) {approx_equal} 20A-1.34 MeV. This estimate is consistent with the mass errors found in large shell model calculations along the N=126 line, and with local mass error estimated using the Garvey-Kelson relations, all being smaller than 100 keV.

  1. Upper limit on spontaneous supercurrents in Sr2RuO4

    SciTech Connect

    Chung, Suk Bum

    2010-04-05

    It is widely believed that the perovskite Sr{sub 2}RuO{sub 4} is an unconventional superconductor with broken time reversal symmetry. It has been predicted that superconductors with broken time reversal symmetry should have spontaneously generated supercurrents at edges and domain walls. We have done careful imaging of the magnetic fields above Sr{sub 2}RuO{sub 4} single crystals using scanning Hall bar and SQUID microscopies, and see no evidence for such spontaneously generated supercurrents. We use the results from our magnetic imaging to place upper limits on the spontaneously generated supercurrents at edges and domain walls as a function of domain size. For a single domain, this upper limit is below the predicted signal by two orders of magnitude. We speculate on the causes and implications of the lack of large spontaneous supercurrents in this very interesting superconducting system.

  2. The cosmic-ray antiproton flux - An upper limit near that predicted for secondary production

    NASA Technical Reports Server (NTRS)

    Badhwar, G. D.; Cleghorn, T.; Golden, R. L.; Lacy, J. L.; Zipse, J. E.; Daniel, R. R.; Stephens, S. A.

    1977-01-01

    Data gathered from a balloon flight of a superconducting-magnet spectrometer have been examined for the presence of cosmic-ray antiprotons. The ratio of antiprotons to protons, p(-)/p, in cosmic rays was found to be (0.03 + or - 3.3) ten-thousandths in the rigidity interval from 4.2 to 12.5 GV. The 95%-confidence-level upper limit for p(-)/p is thus 0.00066. This upper limit is in strong contradiction to the prediction of the closed-galaxy model of Rasmussen and Peters (1975), but is not inconsistent with the prediction of the modified closed-galaxy model of Peters and Westergaard (1977). It is nearly equal to the predictions of conventional propagation models. This result provides an independent confirmation of the absence of primary antimatter in the cosmic rays at a level of approximately a few ten-thousandths.

  3. Upper thermal limits of the hearts of Arctic cod Boreogadus saida: adults compared with larvae.

    PubMed

    Drost, H E; Fisher, J; Randall, F; Kent, D; Carmack, E C; Farrell, A P

    2016-02-01

    Wild adult and reared larval Boreogadus saida were acclimated to 3·5° C before testing their cardiac response to acute warming. Heart rate transition temperatures during warming were similar for adult and larval hearts, except that the maximum temperature for heart rate was 3° C warmer for adults. Thus, in a rapidly warming Arctic Ocean, the upper temperature limit for larval rather than adult B. saida appears more likely to dictate the southern range of the species. PMID:26608719

  4. Measurement of upper limits for {upsilon}{yields}{gamma}+R decays

    SciTech Connect

    Rosner, J. L.; Adam, N. E.; Alexander, J. P.; Cassel, D. G.; Duboscq, J. E.; Ehrlich, R.; Fields, L.; Galik, R. S.; Gibbons, L.; Gray, R.; Gray, S. W.; Hartill, D. L.; Heltsley, B. K.; Hertz, D.; Jones, C. D.; Kandaswamy, J.; Kreinick, D. L.; Kuznetsov, V. E.; Mahlke-Krueger, H.; Onyisi, P. U. E.

    2007-12-01

    We report on a study of exclusive radiative decays {upsilon}(nS){yields}{gamma}+R (n=1, 2, 3), with R a narrow resonant hadronic state decaying into four or more charged particles (plus possible neutrals). Using data collected from the CLEO III detector at the Cornell Electron Storage Ring, we present upper limits of order 10{sup -4} for such bottomonium two-body decays as a function of the mass M{sub R} recoiling opposite the photon.

  5. Upper thermal limits of the hearts of Arctic cod Boreogadus saida: adults compared with larvae.

    PubMed

    Drost, H E; Fisher, J; Randall, F; Kent, D; Carmack, E C; Farrell, A P

    2016-02-01

    Wild adult and reared larval Boreogadus saida were acclimated to 3·5° C before testing their cardiac response to acute warming. Heart rate transition temperatures during warming were similar for adult and larval hearts, except that the maximum temperature for heart rate was 3° C warmer for adults. Thus, in a rapidly warming Arctic Ocean, the upper temperature limit for larval rather than adult B. saida appears more likely to dictate the southern range of the species.

  6. CALET Upper Limits on X-Ray and Gamma-Ray Counterparts of GW151226

    NASA Astrophysics Data System (ADS)

    Adriani, O.; Akaike, Y.; Asano, K.; Asaoka, Y.; Bagliesi, M. G.; Bigongiari, G.; Binns, W. R.; Bonechi, S.; Bongi, M.; Brogi, P.; Buckley, J. H.; Cannady, N.; Castellini, G.; Checchia, C.; Cherry, M. L.; Collazuol, G.; Di Felice, V.; Ebisawa, K.; Fuke, H.; Guzik, T. G.; Hams, T.; Hareyama, M.; Hasebe, N.; Hibino, K.; Ichimura, M.; Ioka, K.; Ishizaki, W.; Israel, M. H.; Javaid, A.; Kasahara, K.; Kataoka, J.; Kataoka, R.; Katayose, Y.; Kato, C.; Kawanaka, N.; Kawakubo, Y.; Kitamura, H.; Krawczynski, H. S.; Krizmanic, J. F.; Kuramata, S.; Lomtadze, T.; Maestro, P.; Marrocchesi, P. S.; Messineo, A. M.; Mitchell, J. W.; Miyake, S.; Mizutani, K.; Moiseev, A. A.; Mori, K.; Mori, M.; Mori, N.; Motz, H. M.; Munakata, K.; Murakami, H.; Nakagawa, Y. E.; Nakahira, S.; Nishimura, J.; Okuno, S.; Ormes, J. F.; Ozawa, S.; Pacini, L.; Palma, F.; Papini, P.; Penacchioni, A. V.; Rauch, B. F.; Ricciarini, S.; Sakai, K.; Sakamoto, T.; Sasaki, M.; Shimizu, Y.; Shiomi, A.; Sparvoli, R.; Spillantini, P.; Stolzi, F.; Takahashi, I.; Takayanagi, M.; Takita, M.; Tamura, T.; Tateyama, N.; Terasawa, T.; Tomida, H.; Torii, S.; Tsunesada, Y.; Uchihori, Y.; Ueno, S.; Vannuccini, E.; Wefel, J. P.; Yamaoka, K.; Yanagita, S.; Yoshida, A.; Yoshida, K.; Yuda, T.

    2016-09-01

    We present upper limits in the hard X-ray and gamma-ray bands at the time of the Laser Interferometer Gravitational-wave Observatory (LIGO) gravitational-wave event GW151226 derived from the CALorimetric Electron Telescope (CALET) observation. The main instrument of CALET, CALorimeter (CAL), observes gamma-rays from ∼1 GeV up to 10 TeV with a field of view of ∼2 sr. The CALET gamma-ray burst monitor (CGBM) views ∼3 sr and ∼2π sr of the sky in the 7 keV–1 MeV and the 40 keV–20 MeV bands, respectively, by using two different scintillator-based instruments. The CGBM covered 32.5% and 49.1% of the GW151226 sky localization probability in the 7 keV–1 MeV and 40 keV–20 MeV bands respectively. We place a 90% upper limit of 2 × 10‑7 erg cm‑2 s‑1 in the 1–100 GeV band where CAL reaches 15% of the integrated LIGO probability (∼1.1 sr). The CGBM 7σ upper limits are 1.0 × 10‑6 erg cm‑2 s‑1 (7–500 keV) and 1.8 × 10‑6 erg cm‑2 s‑1 (50–1000 keV) for a 1 s exposure. Those upper limits correspond to the luminosity of 3–5 × 1049 erg s‑1, which is significantly lower than typical short GRBs.

  7. Pale nasal mucosa affects airflow limitations in upper and lower airways in asthmatic children

    PubMed Central

    Odajima, Hiroshi; Yamada, Atsunobu; Taba, Naohiko; Murakami, Yoko; Nishima, Sankei

    2016-01-01

    Background Severe asthmatics are thought to have severer rhinitis than mild asthmatics. A pale nasal mucosa is a typical clinical finding in subjects with severe allergic rhinitis. Objective The aim of this study was to investigate whether a pale nasal mucosa affects airflow limitations in the upper and lower airways in asthmatic children. Methods Rhinomanometry, nasal scraping, and spirometry were performed in 54 asthmatic children (median age, 10 years). The nasal mucosa was evaluated by an otolaryngologist. Thirty-seven patients were treated with inhaled corticosteroids, and 11 patients were treated with intranasal corticosteroids. Results Subjects with a pale nasal mucosa (n = 23) exhibited a lower nasal airflow (p < 0.05) and a larger number of nasal eosinophils (p < 0.05) in the upper airway as well as lower pulmonary functional parameters (p < 0.05 for all comparisons), i.e., the forced vital capacity (FVC), the forced expiratory volume in 1 second, and the peak expiratory flow, compared with the subjects who exhibited a normal or pinkish mucosa (n = 31). No significant difference in the forced expiratory flow between 25%–75% of the FVC, regarded as indicating the peripheral airway, was observed between the 2 groups. Conclusion A pale nasal mucosa may be a predictor of eosinophil infiltration of the nasal mucosa and central airway limitations in asthmatic children. When allergists observe a pale nasal mucosa in asthmatic children, they should consider the possibility of airflow limitations in not only the upper airway, but also the lower airway. PMID:27803882

  8. Paget-Schroetter syndrome: diagnostic limitations of imaging upper extremity deep vein thrombosis.

    PubMed

    Jourdain, Victor; Goldenberg, William D; Matteucci, Michael; Auten, Jonathan

    2016-03-01

    Paget-Schroetter syndrome is a rare but potentially debilitating condition affecting young, otherwise healthy individuals. This condition, also known as effort thrombosis, is an upper extremity deep vein thrombosis classically caused by anatomical abnormalities compressing the neurovascular structures of the thoracic outlet. The diagnosis is important to emergency medicine providers due to its secondary morbidity and mortality. Common complications affecting these active adults are pulmonary embolism and postthrombotic syndrome. Most patients report a precedent history of vigorous exercise or activity involving the upper extremities. We present a case of a 23-year-old man with redness and swelling of his dominant arm after weightlifting. Previous literature describes Paget-Schroetter syndrome from repetitive activities. The report highlights the limitations of imaging studies in proximal upper extremity deep vein thromboses. The initial selected imaging study, Doppler ultrasound, was negative in our case and was followed by a nondiagnostic computed tomographic venogram. Although ultrasound is the preferred diagnostic imaging modality, it is limited when thrombosis is present in the noncompressible region of the clavicle. Magnetic resonance venogram or computed tomographic venogram is recommended if index of suspicion is high and the ultrasound shows normal results, but these studies are highly dependent on technique, flow, and timing. The eventual diagnosis of axillosubclavian thrombosis was obtained only after specialty consultation and formal venography. This case discusses the limitations of each imaging modality and the importance of a comprehensive clinical approach to this rare diagnosis.

  9. Upper limits on the luminosity of the progenitor of Type Ia supernova SN 2014J

    NASA Astrophysics Data System (ADS)

    Nielsen, M. T. B.; Gilfanov, M.; Bogdán, Á.; Woods, T. E.; Nelemans, G.

    2014-08-01

    We analysed archival data of Chandra pre-explosion observations of the position of SN 2014J in M82. No X-ray source at this position was detected in the data, and we calculated upper limits on the luminosities of the progenitor. These upper limits allow us to firmly rule out an unobscured supersoft X-ray source progenitor with a photospheric radius comparable to the radius of white dwarf near the Chandrasekhar mass (˜1.38 M⊙) and mass accretion rate in the interval where stable nuclear burning can occur. However, due to a relatively large hydrogen column density implied by optical observations of the supernova, we cannot exclude a supersoft source with lower temperatures, kT ≲ 70 eV. We find that the supernova is located in the centre of a large structure of soft diffuse emission, about 200 pc across. The mass, ˜3 × 104 M⊙ and short cooling time of the gas, τcool ˜ 8 Myr, suggest that it is a supernova-inflated superbubble, associated with the region of recent star formation. If SN 2014J is indeed located inside the bubble, it likely belongs to the prompt population of Type Ia supernovae, with a delay time as short as ˜50 Myr. Finally, we analysed the one existing post-supernova Chandra observation and placed upper limit of ˜(1-2) × 1037 erg s-1 on the X-ray luminosity of the supernova itself.

  10. Adherence to balance tolerance limits at the Upper Mississippi Science Center, La Crosse, Wisconsin.

    USGS Publications Warehouse

    Myers, C.T.; Kennedy, D.M.

    1998-01-01

    Verification of balance accuracy entails applying a series of standard masses to a balance prior to use and recording the measured values. The recorded values for each standard should have lower and upper weight limits or tolerances that are accepted as verification of balance accuracy under normal operating conditions. Balance logbooks for seven analytical balances at the Upper Mississippi Science Center were checked over a 3.5-year period to determine if the recorded weights were within the established tolerance limits. A total of 9435 measurements were checked. There were 14 instances in which the balance malfunctioned and operators recorded a rationale in the balance logbook. Sixty-three recording errors were found. Twenty-eight operators were responsible for two types of recording errors: Measurements of weights were recorded outside of the tolerance limit but not acknowledged as an error by the operator (n = 40); and measurements were recorded with the wrong number of decimal places (n = 23). The adherence rate for following tolerance limits was 99.3%. To ensure the continued adherence to tolerance limits, the quality-assurance unit revised standard operating procedures to require more frequent review of balance logbooks.

  11. Upper limits on the probability of an interstellar civilization arising in the local Solar neighbourhood

    NASA Astrophysics Data System (ADS)

    Cartin, Daniel

    2015-10-01

    At this point in time, there is very little empirical evidence on the likelihood of a space-faring species originating in the biosphere of a habitable world. However, there is a tension between the expectation that such a probability is relatively high (given our own origins on Earth), and the lack of any basis for believing the Solar System has ever been visited by an extraterrestrial colonization effort. From the latter observational fact, this paper seeks to place upper limits on the probability of an interstellar civilization arising on a habitable planet in its stellar system, using a percolation model to simulate the progress of such a hypothetical civilization's colonization efforts in the local Solar neighbourhood. To be as realistic as possible, the actual physical positions and characteristics of all stars within 40 parsecs of the Solar System are used as possible colony sites in the percolation process. If an interstellar civilization is very likely to have such colonization programmes, and they can travel over large distances, then the upper bound on the likelihood of such a species arising per habitable world is of the order of 10-3 on the other hand, if civilizations are not prone to colonize their neighbours, or do not travel very far, then the upper limiting probability is much larger, even of order one.

  12. Experimental upper limits on branching fractions for unexpected decay modes of the tau lepton

    SciTech Connect

    Hayes, K.G.; Perl, M.L.; Alam, M.S.; Boyarski, A.M.; Breidenbach, M.; Burke, D.L.; Dorenbosch, J.; Dorfan, J.M.; Feldman, G.J.; Franklin, M.E.B.; Hanson, G.; Himel, T.; Hitlin, D.G.; Hollebeek, R.J.; Innes, W.R.; Jaros, J.A.; Jenni, P.; Larsen, R.R.; Lueth, V.; Richter, B.; Roussarie, A.; Scharre, D.L.; Schindler, R.H.; Schwitters, R.F.; Siegrist, J.L.; Taureg, H.; Tonutti, M.; Vidal, R.A.; Weiss, J.M.; Zaccone, H.; Abrams, G.S.; Blocker, C.A.; Blondel, A.; Carithers, W.C.; Chinowsky, W.; Coles, M.W.; Cooper, S.; Dieterle, W.E.; Dillon, J.B.; Eaton, M.W.; Gidal, G.; Goldhaber, G.; Johnson, A.D.; Kadyk, J.A.; Lankford, A.J.; Levi, M.; Millikan, R.E.; Nelson, M.E.; Pang, C.Y.; Patrick, J.F.; Strait, J.; Trilling, G.H.; Vella, E.N.; Videau, I.

    1982-06-01

    Searches for 12 neutrinoless decay modes of the tau which violate lepton-number conservation have been made using the reaction e/sup +/e/sup -/..-->..tau/sup +/tau/sup -/. No evidence for lepton-number violation is observed, and we have set upper limits (90% C.L.) on the branching ratio for each decay mode. The branching-ratio limits on the radiative decays tau..--> mu gamma.. and tau..-->..e..gamma.. are 0.055 and 0.064, respectively. For the charged lepton decays tau..-->..eee, tau..-->..e..mu mu.., tau..--> mu..ee, and tau..--> mu mu mu.., the branching ratio limits are 0.040, 0.033, 0.044, and 0.049%, respectively. Upper limits on the branching ratios for the following charged lepton-neutral hadron decays are: tau..-->..erho/sup 0/ (0.037%), tau..--> mu..rho/sup 0/ (0.044%), tau..-->..eK/sup 0/ (0.13%), tau..--> mu..K/sup 0/ (0.10%), tau..-->..e..pi../sup 0/ (0.21%), and tau..--> mu pi../sup 0/ (0.082%). We also use these data to search for the pair production in e/sup +/e/sup -/ annihilation of some unconventional particles with masses less than about 3 GeV/c/sup 2/.

  13. Upper limits to the interstellar radiation field between 775 and 1050 A

    NASA Technical Reports Server (NTRS)

    Paresce, F.; Bowyer, S.

    1976-01-01

    A 40-A resolution extreme-ultraviolet spectrometer, sensitive to radiation in the 775-1050 A band, was flown on a Black Brant VC rocket to measure the night sky brightness in this region of the electromagnetic spectrum. A weak signal above background was recorded in most channels as the spectrometer's field of view scanned the sky in the vicinity of the galactic plane from Monoceros to Andromeda. Because the earth's upper atmosphere may produce some radiation in this wavelength region, the possibility cannot be excluded that some or all of the observed signal is terrestrial in origin. However, observational upper limits can be established at the 95-per cent confidence level for the intensity of an extraterrestrial extreme ultraviolet background which ranges from 6 millionths erg/sq cm/s/sr/A at 1050 A to 4 ten-millionths erg/sq cm/s/sr/A at 775 A. These results are consistent with existing theoretical predictions.

  14. An upper bound to time-averaged space-charge limited diode currents

    NASA Astrophysics Data System (ADS)

    Griswold, M. E.; Fisch, N. J.; Wurtele, J. S.

    2010-11-01

    The Child-Langmuir law limits the steady-state current density across a one-dimensional planar diode. While it is known that the peak current density can surpass this limit when the boundary conditions vary in time, it remains an open question of whether the average current can violate the Child-Langmuir limit under time-dependent conditions. For the case where the applied voltage is constant but the electric field at the cathode is allowed to vary in time, one-dimensional particle-in-cell simulations suggest that such a violation is impossible. Although a formal proof is not given, an upper bound on the time-averaged current density is offered.

  15. An upper bound to time-averaged space-charge limited diode currents

    SciTech Connect

    Griswold, M. E.; Fisch, N. J.; Wurtele, J. S.

    2010-11-15

    The Child-Langmuir law limits the steady-state current density across a one-dimensional planar diode. While it is known that the peak current density can surpass this limit when the boundary conditions vary in time, it remains an open question of whether the average current can violate the Child-Langmuir limit under time-dependent conditions. For the case where the applied voltage is constant but the electric field at the cathode is allowed to vary in time, one-dimensional particle-in-cell simulations suggest that such a violation is impossible. Although a formal proof is not given, an upper bound on the time-averaged current density is offered.

  16. INTEGRAL gamma-ray upper limit on the gravitational wave GW150914

    NASA Astrophysics Data System (ADS)

    Ferrigno, Carlo; Ubertini, Pietro; Courvoisier, Thierry; Kuulkers, Erik; Lebrun, Francois; Brandt, S.; Natalucci, Lorenzo; Laurent, Philippe; Bozzo, Enrico; Roques, Jean-Pierre; Mereghetti, Sandro; Savchenko, Volodymyr

    2016-07-01

    Using observations of the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL), we put tight upper limits on the gamma-ray and hard X-ray prompt emission associated with the gravitational wave event GW150914, discovered by the LIGO/Virgo collaboration. The omni-directional view of the INTEGRAL/SPI-ACS has allowed us to constrain the fraction of energy emitted in the hard X-ray electromagnetic component for the full high-probability sky region of LIGO/Virgo trigger. Our upper limits on the hard X-ray fluence at the time of the event range from F_{γ}=2 × 10^{-8} erg cm^{-2} to F_{γ}=10^{-6} erg cm^{-2} in the 75 keV - 2 MeV energy range for typical spectral models. Our results constrain the ratio of the energy promptly released in gamma-rays in the direction of the observer to the gravitational wave energy E_γ/E_{GW}<10^{-6}. We discuss the implication of gamma-ray limits on the characteristics of the gravitational wave source, based on the available predictions for prompt electromagnetic emission for this and forthcoming events. Our team has a memorandum of understanding to follow-up possible triggers issued in near real time from the analysis of the gravitational wave teams.

  17. INTEGRAL upper limits on gamma-ray emission associated with the gravitational wave event GW150914

    NASA Astrophysics Data System (ADS)

    Savchenko, Volodymyr; Ferrigno, Carlo; Mereghetti, Sandro; Natalucci, Lorenzo; Bazzano, Angela; Bozzo, Enrico; Courvoisier, Thierry J.-L.; Brandt, Soren; Hanlon, Lorraine; Kuulkers, Erik; Laurent, Philippe; Lebrun, François; Roques, Jean-Pierre; Ubertini, Pietro; Weidenspointner, Georg

    2016-04-01

    Using observations of the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL), we put tight upper limits on the gamma-ray and hard X-ray prompt emission associated with the gravitational wave event GW150914, discovered by the LIGO/Virgo collaboration. The omni-directional view of the INTEGRAL/SPI-ACS has allowed us to constrain the fraction of energy emitted in the hard X-ray electromagnetic component for the full high-probability sky region of LIGO/Virgo trigger. Our upper limits on the hard X-ray fluence at the time of the event range from Fγ=2x10-8 erg cm-2 to Fγ=10-6 erg cm-2 in the 75 keV - 2 MeV energy range for typical spectral models. Our results constrain the ratio of the energy promptly released in gamma-rays in the direction of the observer to the gravitational wave energy Eγ/EGW<10-6. We discuss the implication of gamma-ray limits on the characteristics of the gravitational wave source, based on the available predictions for prompt electromagnetic emission.

  18. INTEGRAL upper limits on gamma-ray emission associated with the gravitational wave event GW150914

    NASA Astrophysics Data System (ADS)

    Savchenko, V.; Ferrigno, C.; Mereghetti, S.; Natalucci, L.; Kuulkers, E.

    2016-06-01

    Using observations of the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL), we put tight upper limits on the gamma-ray and hard X-ray prompt emission associated with the gravitational wave event GW150914, discovered by the LIGO/Virgo collaboration. The omni-directional view of the INTEGRAL/SPI-ACS has allowed us to constrain the fraction of energy emitted in the hard X-ray electromagnetic component for the full high-probability sky region of LIGO/Virgo trigger. Our upper limits on the hard X-ray fluence at the time of the event range from F_{γ}=2 × 10^{-8} erg cm^{-2} to F_{γ}=10^{-6} erg cm^{-2} in the 75 keV - 2 MeV energy range for typical spectral models. Our results constrain the ratio of the energy promptly released in gamma-rays in the direction of the observer to the gravitational wave energy E_γ/E_{GW}<10^{-6}. We discuss the implication of gamma-ray limits on the characteristics of the gravitational wave source, based on the available predictions for prompt electromagnetic emission. This work has been possible thanks to a Memorandum of Understanding with the LIGO-Virgo scientific collaboration and is presented on behalf of a larger collaboration.

  19. Metallic species, oxygen and silicon in the lunar exosphere: Upper limits and prospects for LADEE measurements

    NASA Astrophysics Data System (ADS)

    Sarantos, Menelaos; Killen, Rosemary M.; Glenar, David A.; Benna, Mehdi; Stubbs, Timothy J.

    2012-03-01

    The only species that have been so far detected in the lunar exosphere are Na, K, Ar, and He. However, models for the production and loss of species derived from the lunar regolith through micrometeoroid impact vaporization, sputtering, and photon-stimulated desorption, predict that a host of other species should exist in the lunar exosphere. Assuming that loss processes are limited to ballistic escape, photoionization, and recycling to the surface, we have computed column abundances and compared them to published upper limits for the Moon. Only for Ca do modeled abundances clearly exceed the available measurements. This result suggests the relevance of some loss processes that were not included in the model, such as the possibility of gas-to-solid phase condensation during micrometeoroid impacts or the formation of stable metallic oxides. Our simulations and the recalculation of efficiencies for resonant light scattering show that models for other species studied are not well constrained by existing measurements. This fact underlines the need for improved remote and in situ measurements of the lunar exosphere such as those planned by the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft. Our simulations of the LADEE neutral mass spectrometer and visible/ultraviolet spectrometer indicate that LADEE measurements promise to provide definitive observations or set stringent upper limits for all regolith-driven exospheric species. We predict that observations by LADEE will constrain assumed model parameters for the exosphere of the Moon.

  20. Metallic Species, Oxygen and Silicon in the Lunar Exosphere: Upper Limits and Prospects for LADEE Measurements

    NASA Technical Reports Server (NTRS)

    Sarantos, Menelaos; Killen, Rosemary M.; Glenar, David A.; Benna, Mehdi; Stubbs, Timothy J.

    2011-01-01

    The only species that have been continued in the lunar exosphere are Na, K, Ar, and He. Models for the production and loss of lunar regolith-derived exospheric species from source processes including micrometeoroid impact vaporization, sputtering. and, for Na and K, photon-stimulated desorption, predict a host of other species should exist in the lunar exosphere. Assuming that loss processes are limited to ballistic escape and recycling to the surface, we have computed column abundances and compared them to published upper limits from the Moon and to detected abundances from Mercury. Only for Ca do the available measurements show a clear deficiency compared to the model estimates. This result suggests the importance of loss processes not included in the model, such as the possibility of gas-to-solid phase condensation during micrometeoroid impacts or the formation of stable metallic oxides, and underlines the need for improved spectroscopic measurements of the lunar exosphere. Simulations of the neutral mass (NMS) and visible/ultraviolet spectrometry (UVS) investigations planned by the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft are presented. Our calculations indicate that LADEE measurements promise to make definitive observations or set stringent upper limits for all regolith-driven exospheric species. Our models, along with LADEE observations, will constrain assumed model parameters for the Moon, such as sticking coefficients, source processes. and velocity distributions.

  1. Upper Limit to Ambient H Ly-alpha Emission from Io

    NASA Astrophysics Data System (ADS)

    Trafton, L. M.

    1999-09-01

    We report an upper limit of 70 R to Io's disk-averaged ambient H Ly-alpha Emission based on HST observations obtained during Aug 20-29, 1994 using the Goddard High Resolution Spectrograph. The data were obtained with the Ech-A grating and the square Large Science Aperture (1."74 on a side) with the solar-blind Digicon detector. The spectral resolution corresponds to ~ 53m Angstroms for a square object the size of Io (0."90). The observations were taken when Io was near western elongation and at low magnetic latitudes; i.e., when io was well-immersed in the plasma torus. At the time of the observations, the interstellar wind was inclined 36deg to Jupiter's line of sight. Both the geocoronal and ISM H emission profiles were blue-shifted essentially clear of the central wavelength of Io's ambient H Ly-alpha profile; or of the diffusely reflected solar profile. We did not detect this reflected solar component. Our upper limit for iogenic H emision is 2.7 times lower than the corresonding disk-averaged intensity of 211 R for H Ly-alpha detected by Roesler et al. (Science 283, 353; 1999) using the STIS instrument on HST during 1997, also near western elongation. This result, and our failure to detect the reflected solar line, suggests that Io's detected H Ly-alpha emission is not diffusely reflected solar light but is temporally variable. Upper limits are also set on SI fluorescence from Io.

  2. Statistical analysis of detection of, and upper limits on, dark matter lines

    SciTech Connect

    Conrad, Jan; Ylinen, Tomi; Scargle, Jeffrey

    2007-07-12

    In this note we present calculations of coverage and power for three different methods which could be used to calculate upper limits and/or claim discovery in a GLAST-LAT search for a dark matter line. The methods considered are Profile Likelihood, Bayesian factors and likelihood ratio confidence intervals and the calculations are done considering a simple benchmark model of two uncorrelated Poissonian measurements. Profile likelihood has the best coverage properties, the standard {chi}2 test the worst. For the power, the situation is vice-versa. In choosing a method one has to consider the false detection rate (1 - coverage) and counterweigh it to the possible achievable power.

  3. Upper limits on the strength of periodic gravitational waves from PSR J1939+2134

    SciTech Connect

    B. Allen et al.

    2003-12-11

    The first science run of the LIGO and GEO gravitational wave detectors presented the opportunity to test methods of searching for gravitational waves from known pulsars. Here we present new direct upper limits on the strength of waves from the pulsar PSR J1939+2134 using two independent analysis methods, one in the frequency domain using frequentist statistics and one in the time domain using Bayesian inference. Both methods show that the strain amplitude at Earth from this pulsar is less than a few times 10{sup -22}.

  4. Upper limit on the diffuse flux of ultrahigh energy tau neutrinos from the Pierre Auger Observatory.

    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; 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; Boratav, M; 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; 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; de Mello Junior, W J M; de Mello Neto, J R T; DeMitri, I; de Souza, V; del Peral, L; Deligny, O; Della Selva, A; Delle Fratte, C; Dembinski, H; Di Giulio, C; Diaz, J C; Dobrigkeit, C; D'Olivo, J C; 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; Facal San Luis, P; Falcke, H; Farrar, G; Fauth, A C; Fazzini, N; Ferrer, F; Ferry, S; Fick, B; Filevich, A; Filipcic, A; Fleck, I; Fonte, R; Fracchiolla, C E; Fulgione, W; García, B; García Gámez, D; Garcia-Pinto, D; Garrido, X; Geenen, H; Gelmini, G; Gemmeke, H; Ghia, P L; Giller, M; Glass, H; Gold, M S; Golup, G; Gomez Albarracin, F; Gómez Berisso, M; Gómez Herrero, R; Gonçalves, P; Gonçalves do Amaral, M; 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; 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; Horneffer, A; Horvat, M; Hrabovský, M; Huege, T; Hussain, M; Iarlori, M; Insolia, A; Ionita, F; Italiano, A; Kaducak, M; Kampert, K H; Karova, T; 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; Leigui de Oliveira, M A; Letessier-Selvon, A; Leuthold, M; Lhenry-Yvon, I; López, R; Lopez Agüera, A; Lozano Bahilo, J; Luna García, R; Maccarone, M C; Macolino, C; Maldera, S; Mancarella, G; Manceñido, M E; Mandat, D; Mantsch, P; Mariazzi, A G; Maris, I C; Marquez Falcon, H R; Martello, D; Martínez, J; Martínez Bravo, O; 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; Meli, A; Melo, D; Menichetti, E; Menschikov, A; Meurer, Chr; Meyhandan, R; Micheletti, M I; Miele, G; Miller, W; Mollerach, S; Monasor, M; Monnier Ragaigne, D; 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; Nguyen Thi, 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; Pakk Selmi-Dei, D; 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; Petrera, S; Petrinca, P; Petrov, Y; Pham Ngoc, Diep; Pham Ngoc, Dong; Pham Thi, T N; 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; Rodríguez Frías, D; Rodriguez Martino, J; Rodriguez Rojo, J; Rodriguez-Cabo, I; 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; Schüssler, F; Sciutto, S J; Scuderi, M; Segreto, A; Semikoz, D; Settimo, M; Shellard, R C; Sidelnik, I; Siffert, B B; Sigl, G; Smetniansky De Grande, N; Smiałkowski, A; Smída, R; Smith, A G K; Smith, B E; Snow, G R; Sokolsky, P; Sommers, P; Sorokin, J; Spinka, H; Squartini, R; Strazzeri, E; Stutz, A; Suarez, F; Suomijärvi, T; Supanitsky, A D; Sutherland, M S; Swain, J; Szadkowski, Z; Takahashi, J; Tamashiro, A; Tamburro, A; Taşcău, O; Tcaciuc, R; Thomas, D; Ticona, R; Tiffenberg, J; Timmermans, C; Tkaczyk, W; Todero Peixoto, C J; Tomé, B; Tonachini, A; Torres, I; Torresi, D; Travnicek, P; Tripathi, A; Tristram, G; Tscherniakhovski, D; Tueros, M; Tunnicliffe, V; Ulrich, R; Unger, M; Urban, M; Valdés Galicia, J F; Valiño, I; Valore, L; van den Berg, A M; van Elewyck, V; Vázquez, R A; Veberic, D; Veiga, A; Velarde, A; Venters, T; Verzi, V; Videla, M; Villaseñor, L; Vorobiov, S; Voyvodic, L; Wahlberg, H; Wainberg, O; Walker, P; Warner, D; Watson, A A; Westerhoff, S; Wieczorek, G; Wiencke, L; Wilczyńska, B; Wilczyński, H; Wileman, C; Winnick, M G; Wu, H; Wundheiler, B; Yamamoto, T; Younk, P; Zas, E; Zavrtanik, D; Zavrtanik, M; Zech, A; Zepeda, A; Ziolkowski, M

    2008-05-30

    The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth's crust. Tau leptons from nu(tau) charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 are used to place an upper limit on the diffuse flux of nu(tau) at EeV energies. Assuming an E(nu)(-2) differential energy spectrum the limit set at 90% C.L. is E(nu)(2)dN(nu)(tau)/dE(nu)<1.3 x 10(-7) GeV cm(-2) s(-1) sr(-1) in the energy range 2 x 10(17) eV< E(nu)< 2 x 10(19) eV.

  5. Fermi LAT upper limits on gamma-ray emission from colliding wind binaries

    NASA Astrophysics Data System (ADS)

    Werner, M.; Reimer, O.; Reimer, A.; Egberts, K.

    2012-12-01

    Colliding wind binaries (CWBs) are thought to give rise to a plethora of physical processes including acceleration and interaction of relativistic particles. Consequently, CWBs have been considered as putative gamma-ray emitters since the COS-B era. On the basis of 24 months of Fermi-LAT data, seven CWB systems are analyzed: WR 11, WR 70, WR 125, WR 137, WR 140, WR 146 and WR 147. Specific theoretical predictions for the gamma-ray emission of CWBs identify these systems as the most promising candidates among known WR-binaries due to their respective stellar and orbital parameters. We find no evidence of gamma-ray emission from any of the studied CWB systems and flux upper limits are determined. In some of the studied CWBs the interplay of orbital and stellar parameters render the Fermi data as not sufficiently sensitive to constrain parameters of the emission model. In others large uncertainties in input parameters of the gamma-ray emission model yield a large variance among model parameters that can be accommodated by the data. However, in the case of WR 140 and WR 147, the Fermi upper limits appear to rule out some early model predictions and constrain later theoretical models over a significant parameter space.

  6. The need for a reassessment of the safe upper limit of selenium in drinking water.

    PubMed

    Vinceti, Marco; Crespi, Catherine M; Bonvicini, Francesca; Malagoli, Carlotta; Ferrante, Margherita; Marmiroli, Sandra; Stranges, Saverio

    2013-01-15

    Results of recent epidemiologic studies suggest the need to reassess the safe upper limit in drinking water of selenium, a metalloid with both toxicological and nutritional properties. Observational and experimental human studies on health effects of organic selenium compounds consumed through diet or supplements, and of inorganic selenium consumed through drinking water, have shown that human toxicity may occur at much lower levels than previously surmised. Evidence indicates that the chemical form of selenium strongly influences its toxicity, and that its biological activity may differ in different species, emphasizing the importance of the few human studies on health effects of the specific selenium compounds found in drinking water. Epidemiologic studies that investigated the effects of selenate, an inorganic selenium species commonly found in drinking water, together with evidence of toxicity of inorganic selenium at low levels in from in vitro and animal studies, indicate that health risks may occur at exposures below the current European Union and World Health Organization upper limit and guideline of 10 and 40 μg/l, respectively, and suggest reduction to 1 μg/l in order to adequately protect human health. Although few drinking waters are currently known to have selenium concentrations exceeding this level, the public health importance of this issue should not be overlooked, and further epidemiologic research is critically needed in this area.

  7. Observational upper limits on the gravitational wave production of core collapse supernovae

    NASA Astrophysics Data System (ADS)

    Zhu, Xing-Jiang; Howell, E.; Blair, D.

    2010-11-01

    The upper limit on the energy density of a stochastic gravitational wave (GW) background obtained from the 2-yr science run (S5) of the Laser Interferometer Gravitational-Wave Observatory (LIGO) is used to constrain the average GW production of core collapse supernovae (ccSNe). We assume that the ccSNe rate tracks the star formation history of the Universe and show that the stochastic background energy density depends only weakly on the assumed average source spectrum. Using the ccSNe rate for z <= 10, we scale the generic source spectrum to obtain an observation-based upper limit on the average GW emission. We show that the mean energy emitted in GWs can be constrained within < (0.49-1.98)Msolarc2 depending on the average source spectrum. While these results are higher than the total available gravitational energy in a core collapse event, second- and third-generation GW detectors will enable tighter constraints to be set on the GW emission from such systems.

  8. Upper Limits of Normal for Serum Alanine Aminotransferase Levels in Chinese Han Population

    PubMed Central

    Zheng, Ming-Hua; Shi, Ke-Qing; Fan, Yu-Chen; Liu, Wen-Yue; Lin, Xian-Feng; Li, Ling-Fei; Chen, Yong-Ping

    2012-01-01

    Background and Objectives Serum alanine aminotransferase (ALT) activity is the most common tool for the assessment of liver diseases. However, it is not clear whether the current normal ALT range really discriminate patients with or without liver diseases. The present study was to establish a new normal range of ALT and examine its ability to identify patients with hepatitis B or nonalcoholic fatty liver disease (NAFLD) in Chinese Han population. Methods 53037 adults were included in this study from January 1st 2008 to August 31st 2010. The 95th percentile of ALT in population with relative low risk factors for liver diseases was set as the new upper limits of normal ALT in gender-specific manner. Results The 95th percentile levels at low risk factors for liver diseases were achieved at 35 U/L for men and 23 U/L for women. The concordance statistics for detection were 0.873 (95%CI: 0.865–0.881) for HBV and 0.932 (95%CI: 0.927–0.937) for NAFLD in men while 0.857 (95%CI: 0.850–0.864) for HBV and 0.909 (95%CI: 0.903–0.915) for NAFLD in women. The median sensitivity of the current used ALT upper limit (40 U/L) was 6.6% for HBV and 29.7% for NAFLD and median specificity was 98.7% for men and 99.4% for women. Using our new-derived thresholds, the sensitivities ranged from 35.3% to 61.1% and the specificities were 94.8% for men and 94.6% for women. Conclusions Our results suggest that upper limits of ALT 35 U/L for men and 23 U/L for women in Chinese Han population. Re-consideration of normal limits of ALT should be recommended. Trial Registration ChiCTR.org ChiCTR-OCS-11001173 PMID:22962588

  9. A sensitive upper limit to the circular polarization of the Crab nebula at λ3 mm

    NASA Astrophysics Data System (ADS)

    Wiesemeyer, H.; Thum, C.; Morris, D.; Aumont, J.; Rosset, C.

    2011-04-01

    A new observation of the distribution of the circular polarization over the Crab Nebula supernova remnant yields an upper limit of <0.2% at a radio frequency of 89.2 GHz. This limit is set by the uncertainty in correcting for the instrumental polarization. The raw data were dominated by the conversion of the strong linear polarization to circular in the crosspolarized sidelobes of the 30 m telescope. They were modeled as due to a differential phase gradient between the orthogonally linearly polarized far-field radiation patterns of the two receivers. As the source is tracked these rotate with respect to the radio source distribution on the sky since the telescope has an alt-azimuth mount and a Nasmyth focus. This allows the model to be fit to the raw data and a correction can be made. Our limit of <0.2% is to be compared with <0.03% derived at 610 MHz (Wilson & Weiler 1997, ApJ, 475, 661) and <6% measured at 23 GHz (Wright & Forster 1980, ApJ, 239, 873). These limits are consistent with the polarization expected from an optically thin synchrotron source with the known physical properties of the Crab Nebula. This non-detection does not allow an estimate to be made of the relative contribution to the radio emission from electrons and positrons.

  10. Compact Binary Merger Rates: Comparison with LIGO/Virgo Upper Limits

    NASA Astrophysics Data System (ADS)

    Belczynski, Krzysztof; Repetto, Serena; Holz, Daniel E.; O'Shaughnessy, Richard; Bulik, Tomasz; Berti, Emanuele; Fryer, Christopher; Dominik, Michal

    2016-03-01

    We compare evolutionary predictions of double compact object merger rate densities with initial and forthcoming LIGO/Virgo upper limits. We find that: (i) Due to the cosmological reach of advanced detectors, current conversion methods of population synthesis predictions into merger rate densities are insufficient. (ii) Our optimistic models are a factor of 18 below the initial LIGO/Virgo upper limits for BH-BH systems, indicating that a modest increase in observational sensitivity (by a factor of ˜2.5) may bring the first detections or first gravitational wave constraints on binary evolution. (iii) Stellar-origin massive BH-BH mergers should dominate event rates in advanced LIGO/Virgo and can be detected out to redshift z ≃ 2 with templates including inspiral, merger, and ringdown. Normal stars (\\lt 150 {M}⊙ ) can produce such mergers with total redshifted mass up to {M}{{tot,z}}≃ 400 {M}⊙ . (iv) High black hole (BH) natal kicks can severely limit the formation of massive BH-BH systems (both in isolated binary and in dynamical dense cluster evolution), and thus would eliminate detection of these systems even at full advanced LIGO/Virgo sensitivity. We find that low and high BH natal kicks are allowed by current observational electromagnetic constraints. (v) The majority of our models yield detections of all types of mergers (NS-NS, BH-NS, BH-BH) with advanced detectors. Numerous massive BH-BH merger detections will indicate small (if any) natal kicks for massive BHs.

  11. Dawn Mission’s Search for satellites at Ceres: Upper limits on size of orbital objects

    NASA Astrophysics Data System (ADS)

    McFadden, Lucy-Ann A.; Skillman, David R.; Memarsadeghi, Nargess; Carsenty, Uri; Schroeder, Stefan E.; Li, Jian-Yang Y.; Rayman, Marc D.

    2015-11-01

    Hundreds of asteroids have small secondary satellites or are double, or even multiple body systems; yet dwarf planet Ceres doesn’t and isn’t. Ground-based and space-based telescopic searches have placed upper limits on the size of any secondary bodies gravitationally bound to Ceres of 1-2 km (Gehrels et al 1987, Bieryla et al. 2011). The Dawn project’s satellite working group designed and conducted a search during approach to Ceres and during high orbit concentrating its search close to Ceres’ limb where previous searches could not reach. Over 2000 images for both science and optical navigation were searched. In addition, a dedicated satellite search was conducted during two commanded off-nadir pointings. The acquired images extend 5.5° x 5.5° on either side of Ceres, at a range of ~ 145,000 km and solar phase angle at Ceres of 18°. No moving objects associated with Ceres were detected. The search extended down to Ceres’ limb (previous searches went to 500 km above the limb) and extended the upper limit for the non-detection to 30 +/- 6 and 45 +/-9 meter radius for effective exposure times of 114s and 19s respectively. An additional small search was conducted using the spacecraft's star tracker from which no objects were found. The Dawn mission’s search reduced the previous detection limit from Hubble Space Telescope images by two orders of magnitude. Why some asteroids have satellites and others don’t is a matter for dynamical speculation.

  12. Upper and lower limits of the proton stoichiometry of cytochrome c oxidation in rat liver mitoplasts.

    PubMed

    Reynafarje, B; Costa, L E; Lehninger, A L

    1986-06-25

    The stoichiometry of vectorial H+ translocation coupled to oxidation of added ferrocytochrome c by O2 via cytochrome-c oxidase of rat liver mitoplasts was determined employing a fast-responding O2 electrode. Electron flow was initiated by addition of either ferrocytochrome c or O2. When the rates were extrapolated to level flow, the H+/O ratios in both cases were less than but closely approached 4; the directly observed H+/O ratios significantly exceeded 3.0. The mechanistic H+/O ratio was then more closely fixed by a kinetic approach that eliminates the necessity for measuring energy leaks and is independent of any particular model of the mechanism of energy transduction. From two sets of kinetic measurements, an overestimate and an underestimate and thus the upper and lower limits of the mechanistic H+/O ratio could be obtained. In the first set, the utilization of respiratory energy was systematically varied through changes in the concentrations of valinomycin or K+. From the slope of a plot of the initial rates of H+ ejection (JH) and O2 uptake (JO) obtained in such experiments, the upper limit of the H+/O ratio was in the range 4.12-4.19. In the second set of measurements, the rate of respiratory energy production was varied by inhibiting electron transport. From the slope of a plot of JH versus JO, the lower limit of the H+/O ratio, equivalent to that at level flow, was in the range 3.83-3.96. These data fix the mechanistic H+/O ratio for the cytochrome oxidase reaction of mitoplasts at 4.0, thus confirming our earlier measurements (Reynafarje, B., Alexandre, A., Davies, P., and Lehninger, A. L. (1982) Proc. Natl. Acad. Sci. U.S.A. 79, 7218-7222). Possible reasons for discrepancies in published reports on the H+/O ratio of cytochrome oxidase in various mitochondrial and reconstituted systems are discussed.

  13. Direct Measurements of Upper Limits for Transient Density Fluctuations in the Zodiacal Cloud

    NASA Astrophysics Data System (ADS)

    Olsson, B.

    1997-12-01

    Questions regarding the density of the local zodiacal clouds have recently become important in many areas. Several planned searches for extrasolar system planets require a better knowledge of the behavior of zodiacal clouds, the solar system zodiacal cloud has been suggested as a driving force for glaciations, and it is becoming clear that discussions regarding prebiotic chemistry must include the flux of interplanetary particles onto Earth. No certain upper limits can today be set for transient density variations in the local zodiacal cloud, nor for fluctuations in the particle-flux onto Earth. Some new results have, however, created a possibility to measure this in the geological record. An interdisciplinary project is described. The goal for the project is to set upper limits for the zodiacal dust-flux onto Earth during passages through IRAS dust-bands during the last 2.5 million years, and use these limits to calculate the maximum density of the bands. We estimate the predicted flux of zodiacal particles onto Earth through orbital modeling., where it is assumed that the source for the IRAS dust-bands are a few Hirayama asteroid families. The orbits of the asteroids and the produced dust are integrated to find the times when Earth revolved within a dust-band. This forms the basis for a geochemical analysis of oceanic sediments, lake sediments, ice-cores and loess-deposits, with the goal to find the signal from a passage through a dust-band. Apart from providing an excellent stratigraphic dating tool, the identification and characterization of such a signal would give important information about the behavior of the zodiacal cloud over shorter times (1-2 My). Some astronomical results are presented and compared with sedimentological observations.

  14. Compact binary merger rates: Comparison with LIGO/Virgo upper limits

    DOE PAGES

    Belczynski, Krzysztof; Repetto, Serena; Holz, Daniel E.; O'Shaugnessy, Richard; Bulik, Tomasz; Berti, Emanuele; Fryer, Christopher Lee; Dominik, Michal

    2016-03-03

    Here, we compare evolutionary predictions of double compact object merger rate densities with initial and forthcoming LIGO/Virgo upper limits. We find that: (i) Due to the cosmological reach of advanced detectors, current conversion methods of population synthesis predictions into merger rate densities are insufficient. (ii) Our optimistic models are a factor of 18 below the initial LIGO/Virgo upper limits for BH–BH systems, indicating that a modest increase in observational sensitivity (by a factor of ~2.5) may bring the first detections or first gravitational wave constraints on binary evolution. (iii) Stellar-origin massive BH–BH mergers should dominate event rates in advanced LIGO/Virgo and can be detected out to redshift z sime 2 with templates including inspiral, merger, and ringdown. Normal stars (more » $$\\lt 150\\;{M}_{\\odot }$$) can produce such mergers with total redshifted mass up to $${M}_{{\\rm{tot,z}}}\\simeq 400\\;{M}_{\\odot }$$. (iv) High black hole (BH) natal kicks can severely limit the formation of massive BH–BH systems (both in isolated binary and in dynamical dense cluster evolution), and thus would eliminate detection of these systems even at full advanced LIGO/Virgo sensitivity. We find that low and high BH natal kicks are allowed by current observational electromagnetic constraints. (v) The majority of our models yield detections of all types of mergers (NS–NS, BH–NS, BH–BH) with advanced detectors. Numerous massive BH–BH merger detections will indicate small (if any) natal kicks for massive BHs.« less

  15. Swift X-Ray Upper Limits on Type Ia Supernova Environments

    NASA Technical Reports Server (NTRS)

    Russell, B. R.; Immler, S.

    2012-01-01

    We have considered 53 Type Ia supernovae (SNe Ia) observed by the Swift X-Ray Telescope. None of the SNe Ia are individually detected at any time or in stacked images. Using these data and assuming that the SNe Ia are a homogeneous class of objects, we have calculated upper limits to the X-ray luminosity (0.2-10 keV) and mass-loss rate of L(sub 0.2-10) < 1.7 X 10(exp 38) erg/s and M(dot) < l.l X 10(exp -6) solar M/ yr x (V(sub w))/(10 km/s), respectively. The results exclude massive or evolved stars as the companion objects in SN Ia progenitor systems, but allow the possibility of main sequence or small stars, along with double degenerate systems consisting of two white dwarfs, consistent with results obtained at other wavelengths (e.g., UV, radio) in other studies.

  16. Plasticity of upper thermal limits to acute and chronic temperature variation in Manduca sexta larvae.

    PubMed

    Kingsolver, Joel G; MacLean, Heidi J; Goddin, Silvan B; Augustine, Kate E

    2016-05-01

    In many ectotherms, exposure to high temperatures can improve subsequent tolerance to higher temperatures. However, the differential effects of single, repeated or continuous exposure to high temperatures are less clear. We measured the effects of single heat shocks and of diurnally fluctuating or constant rearing temperatures on the critical thermal maximum (CTmax) for final instar larvae of Manduca sexta Brief (2 h) heat shocks at temperatures of 35°C and above significantly increased CTmax relative to control temperatures (25°C). Increasing mean temperatures (from 25 to 30°C) or greater diurnal fluctuations (from constant to ±10°C) during larval development also significantly increased CTmax Combining these data showed that repeated or continuous temperature exposure during development improved heat tolerance beyond the effects of a single exposure to the same maximum temperature. These results suggest that both acute and chronic temperature exposure can result in adaptive plasticity of upper thermal limits. PMID:26944498

  17. Upper limits to the magnetic field in central stars of planetary nebulae

    SciTech Connect

    Asensio Ramos, A.; Martínez González, M. J.; Manso Sainz, R.; Corradi, R. L. M.; Leone, F.

    2014-06-01

    More than about 20 central stars of planetary nebulae (CSPNs) have been observed spectropolarimetrically, yet no clear, unambiguous signal of the presence of a magnetic field in these objects has been found. We perform a statistical (Bayesian) analysis of all the available spectropolarimetric observations of CSPN to constrain the magnetic fields in these objects. Assuming that the stellar field is dipolar and that the dipole axis of the objects is oriented randomly (isotropically), we find that the dipole magnetic field strength is smaller than 400 G with 95% probability using all available observations. The analysis introduced allows integration of future observations to further constrain the parameters of the distribution, and it is general, so that it can be easily applied to other classes of magnetic objects. We propose several ways to improve the upper limits found here.

  18. Upper limit on the prompt muon flux derived from the LVD underground experiment

    SciTech Connect

    Aglietta, M.; Alpat, B.; Alyea, E. D.; Antonioli, P.; Badino, G.; Bari, G.; Basile, M.; Berezinsky, V. S.; Bersani, F.; Bertaina, M.

    1999-12-01

    We present the analysis of the muon events with all muon multiplicities collected during 21804 h of operation of the first LVD tower. The measured depth-angular distribution of muon intensities has been used to obtain the normalization factor A the power index {gamma} of the primary all-nucleon spectrum, and the ratio R{sub c} of the prompt muon flux to that of {pi} mesons--the main parameters which determine the spectrum of cosmic ray muons at the sea level. The values of {gamma}=2.77{+-}0.05 (68% C.L.) and R{sub c}<2.0x10{sup -3} (95% C.L.) have been obtained. The upper limit to the prompt muon flux favors the models of charm production based on QGSM and the dual parton model. (c) 1999 The American Physical Society.

  19. Upper limits for undetected trace species in the stratosphere of Titan

    SciTech Connect

    Nixon, Connor A.; Achterberg, Richard K.; Teanby, Nicholas A.; Irwin, Patrick G.; Flaud, Jean Marie; Kleiner, I.; Dehayem-kamadjeu, A.; Brown, Linda R.; Sams, Robert L.; Bezard, Bruno; Coustenis, Athena; Ansty, Todd M.; Mamoutkine, Andrei; Vinatier, Sandrine; Bjoraker, Gordon L.; Jennings, Donald E.; Romani, Paul N.; Flasar, F. M.

    2010-11-01

    In this paper we describe a first quantitative search for several molecules in Titans stratosphere ni Cassini CIRS infrared spectra. These are: ammonia (NH3), methanol (CH3OH), formaldehyde (H2CO), and acetonitrile (CH3CN), all of which are predicted by photochemical models but only the last of which observed, and not in the infrared,. We find non-detections in all cases, but derive upper limits on the abundances from low-noise observations at 25 degreesS and 75 degreesN. Comparing these constraints to model predictions, we conclude that CIRS is highly unlikely to see NH3 or CH3OH emissions. However, CH3CN and H2CO are closer to CIRS detectability, and we suggest ways in which the sensitivity threshold may be lowered towards this goal.

  20. 0. 073% (95% C. L. ) upper limit on 17keV neutrino admixture

    SciTech Connect

    Ohshima, T. )

    1992-02-01

    A direct search was made for a threshold kink in [sup 63]Ni [beta]-ray spectrum due possibly to a sizeable admixture of 17keV neutrino. A fine energy scan was performed using a magnetic spectrometer over the specific energy region with very high statistics and a very high signal-to-background ratio. The resultant mixing strength is [vert bar][ital U][vert bar][sup 2]=([minus]0.011[plus minus]0.033(stat.)[plus minus]0.030(sys.) )% and its upper limit [vert bar][ital U][vert bar][sup 2][le]0.073% (95% C.L.). The result clearly excludes neutrinos with [vert bar][ital U][vert bar][sup 2][ge]0.1% for the mass range from 11 to 24keV.

  1. Upper Temperature Limit of Environmental Barrier Coatings for Enabling Propulsion Materials Established

    NASA Technical Reports Server (NTRS)

    Lee, Kang N.; Fox, Dennis S.; Robinson, R. Craig

    2001-01-01

    Silicon-based ceramics, such as SiC/SiC composites and Si3N4, are the prime candidates for hot section structural components of next-generation gas turbines. A key barrier to such an application is the rapid recession of silicon-based ceramics in combustion environments because of the volatilization of silica scale by water vapor (refs. 1 and 2). Environmental barrier coatings (EBC's) were developed to prevent recession in the High Speed Research--Enabling Propulsion Materials (HSR-EPM) Program (refs. 3 and 4). An investigation under the Ultra-Efficient Engine Technology Program was undertaken at the NASA Glenn Research Center to establish the upper temperature limit of the EPM EBC.

  2. Limited surgical treatment of suspected necrotizing fasciitis of the upper extremity with a benign clinical presentation

    PubMed Central

    Gander, Brian; Kaye, Marc; Wollstein, Ronit

    2012-01-01

    Necrotizing fasciitis is a rapidly evolving, potentially fatal infection. Current recommendations advocate antibiotic administration and early aggressive surgical debridement. Aggressive surgery is associated with significant morbidity, leaving patients with substantial tissue loss and complex wounds. A case of suspected necrotizing fasciitis treated with minimal surgery is described. A previously healthy 48-year-old man presented with increased erythema, swelling and blistering of his left upper extremity. Despite a benign systemic clinical presentation, the hand and forearm were suspicious for necrotizing fasciitis, prompting surgical treatment. Surgical exploration found a significant amount of intradermal and subdermal clear fluid. It was decided to limit the amount of debridement. The diagnosis was Wells syndrome, eosinophilic cellulitis. Treated with steroids, the wounds healed uneventfully. It is important to consider the complete clinical picture before aggressive surgical treatment. A negative history for diabetes, atypical clinical presentation and benign operative findings are suggestive of a more benign diagnosis. PMID:23997598

  3. Upper limits for the photoproduction cross section for the Phi--(1860) pentaquark state off the deuteron

    SciTech Connect

    Hovanes Egiyan

    2012-01-01

    We searched for the {Phi}{sup --}(1860) pentaquark in the photoproduction process off the deuteron in the {Xi}{sup -} {pi}{sup -} decay channel using CLAS. The invariant mass spectrum of the {Xi}{sup -} {pi}{sup -} system does not indicate any statistically significant enhancement near the reported mass M = 1.860 GeV. The statistical analysis of the sideband-subtracted mass spectrum yields a 90% confidence level upper limit of 0.7 nb for the photoproduction cross section of {Phi}{sup --}(1860) with a consecutive decay into {Xi}{sup -} {pi}{sup -} in the photon energy range 4.5 GeV < E{sub {gamma}} < 5.5 GeV.

  4. VERITAS UPPER LIMIT ON THE VERY HIGH ENERGY EMISSION FROM THE RADIO GALAXY NGC 1275

    SciTech Connect

    Acciari, V. A.; Benbow, W.; Aliu, E.; Boltuch, D.; Arlen, T.; Celik, O.; Aune, T.; Bautista, M.; Cogan, P.; Beilicke, M.; Buckley, J. H.; Bugaev, V.; Dickherber, R.; Bradbury, S. M.; Byrum, K.; Cannon, A.; Cesarini, A.; Ciupik, L.; Cui, W.; Duke, C.

    2009-12-01

    The recent detection by the Fermi gamma-ray space telescope of high-energy gamma-rays from the radio galaxy NGC 1275 makes the observation of the very high energy (VHE: E>100 GeV) part of its broadband spectrum particularly interesting, especially for the understanding of active galactic nuclei with misaligned multi-structured jets. The radio galaxy NGC 1275 was recently observed by VERITAS at energies above 100 GeV for about 8 hr. No VHE gamma-ray emission was detected by VERITAS from NGC 1275. A 99% confidence level upper limit of 2.1% of the Crab Nebula flux level is obtained at the decorrelation energy of approximately 340 GeV, corresponding to 19% of the power-law extrapolation of the Fermi Large Area Telescope result.

  5. New upper limit on the total neutrino mass from the 2 degree field galaxy redshift survey.

    PubMed

    Elgarøy, Ø; Lahav, O; Percival, W J; Peacock, J A; Madgwick, D S; Bridle, S L; Baugh, C M; Baldry, I K; Bland-Hawthorn, J; Bridges, T; Cannon, R; Cole, S; Colless, M; Collins, C; Couch, W; Dalton, G; De Propris, R; Driver, S P; Efstathiou, G P; Ellis, R S; Frenk, C S; Glazebrook, K; Jackson, C; Lewis, I; Lumsden, S; Maddox, S; Norberg, P; Peterson, B A; Sutherland, W; Taylor, K

    2002-08-01

    We constrain f(nu) identical with Omega(nu)/Omega(m), the fractional contribution of neutrinos to the total mass density in the Universe, by comparing the power spectrum of fluctuations derived from the 2 Degree Field Galaxy Redshift Survey with power spectra for models with four components: baryons, cold dark matter, massive neutrinos, and a cosmological constant. Adding constraints from independent cosmological probes we find f(nu)<0.13 (at 95% confidence) for a prior of 0.1upper limit on the total neutrino mass m(nu,tot)<1.8 eV for "concordance" values of Omega(m) and the Hubble constant. PMID:12190573

  6. Vegetation dynamics at the upper elevational limit of vascular plants in Himalaya

    PubMed Central

    Dolezal, Jiri; Dvorsky, Miroslav; Kopecky, Martin; Liancourt, Pierre; Hiiesalu, Inga; Macek, Martin; Altman, Jan; Chlumska, Zuzana; Rehakova, Klara; Capkova, Katerina; Borovec, Jakub; Mudrak, Ondrej; Wild, Jan; Schweingruber, Fritz

    2016-01-01

    A rapid warming in Himalayas is predicted to increase plant upper distributional limits, vegetation cover and abundance of species adapted to warmer climate. We explored these predictions in NW Himalayas, by revisiting uppermost plant populations after ten years (2003–2013), detailed monitoring of vegetation changes in permanent plots (2009–2012), and age analysis of plants growing from 5500 to 6150 m. Plant traits and microclimate variables were recorded to explain observed vegetation changes. The elevation limits of several species shifted up to 6150 m, about 150 vertical meters above the limit of continuous plant distribution. The plant age analysis corroborated the hypothesis of warming-driven uphill migration. However, the impact of warming interacts with increasing precipitation and physical disturbance. The extreme summer snowfall event in 2010 is likely responsible for substantial decrease in plant cover in both alpine and subnival vegetation and compositional shift towards species preferring wetter habitats. Simultaneous increase in summer temperature and precipitation caused rapid snow melt and, coupled with frequent night frosts, generated multiple freeze-thaw cycles detrimental to subnival plants. Our results suggest that plant species responses to ongoing climate change will not be unidirectional upward range shifts but rather multi-dimensional, species-specific and spatially variable. PMID:27143226

  7. An Upper Limit on the Finescale Anisotropy of the Cosmic Background Radiation at 800-MICRONS

    NASA Astrophysics Data System (ADS)

    Church, S. E.; Lasenby, A. N.; Hills, R. E.

    1993-04-01

    In some models of the early Universe, radiation is reprocessed into the submillimetre and far-infrared by high-redshift dust, without violating COBE limits on the CBR spectrum, but producing secondary anisotropies which should be detectable with ground-based submillimetre telescopes. We describe an attempt to measure these anisotropies at 800 microns using the JCMT. A careful analysis to reduce position-dependent systematics was carried out and we show that, for this experiment, chopping the telescope beam in azimuth rather than RA produces lower systematics. Bayesian likelihood analysis is then used to set an upper limit on CBR fluctuations of {DELTA} T/T <~ 1.46 X 10^-3^ on a coherence scale of 17 arcsec. Data from a similar set of observations made by Kreysa & Chini in 1988 with the IBM 30-m telescope at 1300 microns are reanalysed in the same way to enable a comparison to be made. The results are used to set limits on the generation of cosmic backgrounds from primeval dust.

  8. Vegetation dynamics at the upper elevational limit of vascular plants in Himalaya.

    PubMed

    Dolezal, Jiri; Dvorsky, Miroslav; Kopecky, Martin; Liancourt, Pierre; Hiiesalu, Inga; Macek, Martin; Altman, Jan; Chlumska, Zuzana; Rehakova, Klara; Capkova, Katerina; Borovec, Jakub; Mudrak, Ondrej; Wild, Jan; Schweingruber, Fritz

    2016-01-01

    A rapid warming in Himalayas is predicted to increase plant upper distributional limits, vegetation cover and abundance of species adapted to warmer climate. We explored these predictions in NW Himalayas, by revisiting uppermost plant populations after ten years (2003-2013), detailed monitoring of vegetation changes in permanent plots (2009-2012), and age analysis of plants growing from 5500 to 6150 m. Plant traits and microclimate variables were recorded to explain observed vegetation changes. The elevation limits of several species shifted up to 6150 m, about 150 vertical meters above the limit of continuous plant distribution. The plant age analysis corroborated the hypothesis of warming-driven uphill migration. However, the impact of warming interacts with increasing precipitation and physical disturbance. The extreme summer snowfall event in 2010 is likely responsible for substantial decrease in plant cover in both alpine and subnival vegetation and compositional shift towards species preferring wetter habitats. Simultaneous increase in summer temperature and precipitation caused rapid snow melt and, coupled with frequent night frosts, generated multiple freeze-thaw cycles detrimental to subnival plants. Our results suggest that plant species responses to ongoing climate change will not be unidirectional upward range shifts but rather multi-dimensional, species-specific and spatially variable.

  9. Vegetation dynamics at the upper elevational limit of vascular plants in Himalaya.

    PubMed

    Dolezal, Jiri; Dvorsky, Miroslav; Kopecky, Martin; Liancourt, Pierre; Hiiesalu, Inga; Macek, Martin; Altman, Jan; Chlumska, Zuzana; Rehakova, Klara; Capkova, Katerina; Borovec, Jakub; Mudrak, Ondrej; Wild, Jan; Schweingruber, Fritz

    2016-01-01

    A rapid warming in Himalayas is predicted to increase plant upper distributional limits, vegetation cover and abundance of species adapted to warmer climate. We explored these predictions in NW Himalayas, by revisiting uppermost plant populations after ten years (2003-2013), detailed monitoring of vegetation changes in permanent plots (2009-2012), and age analysis of plants growing from 5500 to 6150 m. Plant traits and microclimate variables were recorded to explain observed vegetation changes. The elevation limits of several species shifted up to 6150 m, about 150 vertical meters above the limit of continuous plant distribution. The plant age analysis corroborated the hypothesis of warming-driven uphill migration. However, the impact of warming interacts with increasing precipitation and physical disturbance. The extreme summer snowfall event in 2010 is likely responsible for substantial decrease in plant cover in both alpine and subnival vegetation and compositional shift towards species preferring wetter habitats. Simultaneous increase in summer temperature and precipitation caused rapid snow melt and, coupled with frequent night frosts, generated multiple freeze-thaw cycles detrimental to subnival plants. Our results suggest that plant species responses to ongoing climate change will not be unidirectional upward range shifts but rather multi-dimensional, species-specific and spatially variable. PMID:27143226

  10. Fermi-LAT upper limits on gamma-ray emission from colliding wind binaries

    NASA Astrophysics Data System (ADS)

    Werner, M.; Reimer, O.; Reimer, A.; Egberts, K.

    2013-07-01

    Context. Colliding wind binaries (CWBs) are thought to give rise to a plethora of physical processes including acceleration and interaction of relativistic particles. Observation of synchrotron radiation in the radio band confirms there is a relativistic electron population in CWBs. Accordingly, CWBs have been suspected sources of high-energy γ-ray emission since the COS-B era. Theoretical models exist that characterize the underlying physical processes leading to particle acceleration and quantitatively predict the non-thermal energy emission observable at Earth. Aims: We strive to find evidence of γ-ray emission from a sample of seven CWB systems: WR 11, WR 70, WR 125, WR 137, WR 140, WR 146, and WR 147. Theoretical modelling identified these systems as the most favourable candidates for emitting γ-rays. We make a comparison with existing γ-ray flux predictions and investigate possible constraints. Methods: We used 24 months of data from the Large Area Telescope (LAT) on-board the Fermi Gamma Ray Space Telescope to perform a dedicated likelihood analysis of CWBs in the LAT energy range. Results: We find no evidence of γ-ray emission from any of the studied CWB systems and determine corresponding flux upper limits. For some CWBs the interplay of orbital and stellar parameters renders the Fermi -LAT data not sensitive enough to constrain the parameter space of the emission models. In the cases of WR140 and WR147, the Fermi -LAT upper limits appear to rule out some model predictions entirely and constrain theoretical models over a significant parameter space. A comparison of our findings to the CWB η Car is made.

  11. 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.

  12. New upper limit on strange quark matter abundance in cosmic rays with the PAMELA space experiment.

    PubMed

    Adriani, O; Barbarino, G C; Bazilevskaya, G A; Bellotti, R; Boezio, M; Bogomolov, E A; Bongi, M; Bonvicini, V; Bottai, S; Bruno, A; Cafagna, F; Campana, D; Carlson, P; Casolino, M; Castellini, G; De Donato, C; De Santis, C; De Simone, N; Di Felice, V; Formato, V; Galper, A M; Karelin, A V; Koldashov, S V; Koldobskiy, S; Krutkov, S Y; Kvashnin, A N; Leonov, A; Malakhov, V; Marcelli, L; Martucci, M; Mayorov, A G; Menn, W; Mergè, M; Mikhailov, V V; Mocchiutti, E; Monaco, A; Mori, N; Munini, R; Osteria, G; Palma, F; Panico, B; Papini, P; Pearce, M; Picozza, P; Ricci, M; Ricciarini, S B; Sarkar, R; Scotti, V; Simon, M; Sparvoli, R; Spillantini, P; Stozhkov, Y I; Vacchi, A; Vannuccini, E; Vasilyev, G; Voronov, S A; Yurkin, Y T; Zampa, G; Zampa, N

    2015-09-11

    In this work we present results of a direct search for strange quark matter (SQM) in cosmic rays with the PAMELA space spectrometer. If this state of matter exists it may be present in cosmic rays as particles, called strangelets, having a high density and an anomalously high mass-to-charge (A/Z) ratio. A direct search in space is complementary to those from ground-based spectrometers. Furthermore, it has the advantage of being potentially capable of directly identifying these particles, without any assumption on their interaction model with Earth's atmosphere and the long-term stability in terrestrial and lunar rocks. In the rigidity range from 1.0 to ∼1.0×10^{3}  GV, no such particles were found in the data collected by PAMELA between 2006 and 2009. An upper limit on the strangelet flux in cosmic rays was therefore set for particles with charge 1≤Z≤8 and mass 4≤A≤1.2×10^{5}. This limit as a function of mass and as a function of magnetic rigidity allows us to constrain models of SQM production and propagation in the Galaxy. PMID:26406816

  13. New Upper Limit on Strange Quark Matter Abundance in Cosmic Rays with the PAMELA Space Experiment

    NASA Astrophysics Data System (ADS)

    Adriani, O.; Barbarino, G. C.; Bazilevskaya, G. A.; Bellotti, R.; Boezio, M.; Bogomolov, E. A.; Bongi, M.; Bonvicini, V.; Bottai, S.; Bruno, A.; Cafagna, F.; Campana, D.; Carlson, P.; Casolino, M.; Castellini, G.; de Donato, C.; de Santis, C.; de Simone, N.; di Felice, V.; Formato, V.; Galper, A. M.; Karelin, A. V.; Koldashov, S. V.; Koldobskiy, S.; Krutkov, S. Y.; Kvashnin, A. N.; Leonov, A.; Malakhov, V.; Marcelli, L.; Martucci, M.; Mayorov, A. G.; Menn, W.; Mergè, M.; Mikhailov, V. V.; Mocchiutti, E.; Monaco, A.; Mori, N.; Munini, R.; Osteria, G.; Palma, F.; Panico, B.; Papini, P.; Pearce, M.; Picozza, P.; Ricci, M.; Ricciarini, S. B.; Sarkar, R.; Scotti, V.; Simon, M.; Sparvoli, R.; Spillantini, P.; Stozhkov, Y. I.; Vacchi, A.; Vannuccini, E.; Vasilyev, G.; Voronov, S. A.; Yurkin, Y. T.; Zampa, G.; Zampa, N.; Pamela Collaboration

    2015-09-01

    In this work we present results of a direct search for strange quark matter (SQM) in cosmic rays with the PAMELA space spectrometer. If this state of matter exists it may be present in cosmic rays as particles, called strangelets, having a high density and an anomalously high mass-to-charge (A /Z ) ratio. A direct search in space is complementary to those from ground-based spectrometers. Furthermore, it has the advantage of being potentially capable of directly identifying these particles, without any assumption on their interaction model with Earth's atmosphere and the long-term stability in terrestrial and lunar rocks. In the rigidity range from 1.0 to ˜1.0 ×103 GV , no such particles were found in the data collected by PAMELA between 2006 and 2009. An upper limit on the strangelet flux in cosmic rays was therefore set for particles with charge 1 ≤Z ≤8 and mass 4 ≤A ≤1.2 ×105 . This limit as a function of mass and as a function of magnetic rigidity allows us to constrain models of SQM production and propagation in the Galaxy.

  14. Upper Limit on the Diffuse Flux of Ultrahigh Energy Tau Neutrinos from the Pierre Auger Observatory

    SciTech Connect

    Abraham, J.; Garcia, B.; Otero, L.; Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Conceicao, R.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Tome, B.; Aglietta, M.; Bonino, R.; Castellina, A.; Chiavassa, A.; Fulgione, W.; Gorgi, A.; Hauschildt, T.; Maldera, S.

    2008-05-30

    The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau neutrinos that interact in Earth's crust. Tau leptons from {nu}{sub {tau}} charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 are used to place an upper limit on the diffuse flux of {nu}{sub {tau}} at EeV energies. Assuming an E{sub {nu}}{sup -2} differential energy spectrum the limit set at 90% C.L. is E{sub {nu}}{sup 2}dN{sub {nu}{sub {tau}}}/dE{sub {nu}}<1.3x10{sup -7} GeV cm{sup -2} s{sup -1} sr{sup -1} in the energy range 2x10{sup 17} eV

  15. Keeping pace with climate change: what is wrong with the evolutionary potential of upper thermal limits?

    PubMed Central

    Santos, Mauro; Castañeda, Luis E; Rezende, Enrico L

    2012-01-01

    The potential of populations to evolve in response to ongoing climate change is partly conditioned by the presence of heritable genetic variation in relevant physiological traits. Recent research suggests that Drosophila melanogaster exhibits negligible heritability, hence little evolutionary potential in heat tolerance when measured under slow heating rates that presumably mimic conditions in nature. Here, we study the effects of directional selection for increased heat tolerance using Drosophila as a model system. We combine a physiological model to simulate thermal tolerance assays with multilocus models for quantitative traits. Our simulations show that, whereas the evolutionary response of the genetically determined upper thermal limit (CTmax) is independent of methodological context, the response in knockdown temperatures varies with measurement protocol and is substantially (up to 50%) lower than for CTmax. Realized heritabilities of knockdown temperature may grossly underestimate the true heritability of CTmax. For instance, assuming that the true heritability of CTmax in the base population is h2 = 0.25, realized heritabilities of knockdown temperature are around 0.08–0.16 depending on heating rate. These effects are higher in slow heating assays, suggesting that flawed methodology might explain the apparently limited evolutionary potential of cosmopolitan D. melanogaster. PMID:23170220

  16. AN UPPER LIMIT ON THE MASS OF THE BLACK HOLE IN URSA MINOR DWARF GALAXY

    SciTech Connect

    Lora, V.; Sanchez-Salcedo, F. J.; Raga, A. C.; Esquivel, A. E-mail: jsanchez@astroscu.unam.mx E-mail: esquivel@nucleares.unam.mx

    2009-07-10

    The well-established correlations between the mass of massive black holes (BHs) in the nuclei of most studied galaxies and various global properties of their hosting galaxy lend support to the idea that dwarf galaxies and globular clusters could also host a BH in their centers. Direct kinematic detection of BHs in dwarf spheroidal (dSph) galaxies is seriously hindered by the small number of stars inside the gravitational influence region of the BH. The aim of this Letter is to establish an upper dynamical limit on the mass of the putative BH in the Ursa Minor (UMi) dSph galaxy. We present direct N-body simulations of the tidal disruption of the dynamical fossil observed in UMi, with and without a massive BH. We find that the observed substructure is incompatible with the presence of a massive BH of (2-3) x 10{sup 4} M {sub sun} within the core of UMi. These limits are consistent with the extrapolation of the M {sub BH}-{sigma} relation to the M {sub BH} < 10{sup 6} M {sub sun} regime. We also show that the BH may be off-center with respect to the center of symmetry of the whole galaxy.

  17. Revised upper limit to energy extraction from a Kerr black hole.

    PubMed

    Schnittman, Jeremy D

    2014-12-31

    We present a new upper limit on the energy that may be extracted from a Kerr black hole by means of particle collisions in the ergosphere (i.e., the "collisional Penrose process"). Earlier work on this subject has focused largely on particles with critical values of angular momentum falling into an extremal Kerr black hole from infinity and colliding just outside the horizon. While these collisions are able to reach arbitrarily high center-of-mass energies, it is very difficult for the reaction products to escape back to infinity, effectively limiting the peak efficiency of such a process to roughly 130%. When we allow one of the initial particles to have impact parameter b>2M, and thus not get captured by the horizon, it is able to collide along outgoing trajectories, greatly increasing the chance that the products can escape. For equal-mass particles annihilating to photons, we find a greatly increased peak energy of Eout≈6×Ein. For Compton scattering, the efficiency can go even higher, with Eout≈14×Ein, and for repeated scattering events, photons can both be produced and escape to infinity with Planck-scale energies. PMID:25615298

  18. Metallic Species, Oxygen and Silicon in the Lunar Exosphere: Upper Limits and Prospects for LADEE Measurements

    NASA Technical Reports Server (NTRS)

    Sarantos, Menelaos; Killen, Rosemary Margaret; Glenar, David A.; Benna, Mehdi; Stubbs, Timothy J.

    2012-01-01

    The only species that have been so far detected in the lunar exosphere are Na, K, Ar,and He. However, models for the production and loss of species derived from the lunarregolith through micrometeoroid impact vaporization, sputtering, and photon-stimulateddesorption, predict that a host of other species should exist in the lunar exosphere.Assuming that loss processes are limited to ballistic escape, photoionization, and recyclingto the surface, we have computed column abundances and compared them to publishedupper limits for the Moon. Only for Ca do modeled abundances clearly exceed theavailable measurements. This result suggests the relevance of some loss processes thatwere not included in the model, such as the possibility of gas-to-solid phasecondensation during micrometeoroid impacts or the formation of stable metallic oxides.Our simulations and the recalculation of efficiencies for resonant light scattering showthat models for other species studied are not well constrained by existingmeasurements. This fact underlines the need for improved remote and in situmeasurements of the lunar exosphere such as those planned by the Lunar Atmosphereand Dust Environment Explorer (LADEE) spacecraft. Our simulations of the LADEEneutral mass spectrometer and visibleultraviolet spectrometer indicate that LADEE measurements promise to provide definitive observations or set stringent upper limitsfor all regolith-driven exospheric species. We predict that observations by LADEE willconstrain assumed model parameters for the exosphere of the Moon.

  19. New upper limit on strange quark matter abundance in cosmic rays with the PAMELA space experiment.

    PubMed

    Adriani, O; Barbarino, G C; Bazilevskaya, G A; Bellotti, R; Boezio, M; Bogomolov, E A; Bongi, M; Bonvicini, V; Bottai, S; Bruno, A; Cafagna, F; Campana, D; Carlson, P; Casolino, M; Castellini, G; De Donato, C; De Santis, C; De Simone, N; Di Felice, V; Formato, V; Galper, A M; Karelin, A V; Koldashov, S V; Koldobskiy, S; Krutkov, S Y; Kvashnin, A N; Leonov, A; Malakhov, V; Marcelli, L; Martucci, M; Mayorov, A G; Menn, W; Mergè, M; Mikhailov, V V; Mocchiutti, E; Monaco, A; Mori, N; Munini, R; Osteria, G; Palma, F; Panico, B; Papini, P; Pearce, M; Picozza, P; Ricci, M; Ricciarini, S B; Sarkar, R; Scotti, V; Simon, M; Sparvoli, R; Spillantini, P; Stozhkov, Y I; Vacchi, A; Vannuccini, E; Vasilyev, G; Voronov, S A; Yurkin, Y T; Zampa, G; Zampa, N

    2015-09-11

    In this work we present results of a direct search for strange quark matter (SQM) in cosmic rays with the PAMELA space spectrometer. If this state of matter exists it may be present in cosmic rays as particles, called strangelets, having a high density and an anomalously high mass-to-charge (A/Z) ratio. A direct search in space is complementary to those from ground-based spectrometers. Furthermore, it has the advantage of being potentially capable of directly identifying these particles, without any assumption on their interaction model with Earth's atmosphere and the long-term stability in terrestrial and lunar rocks. In the rigidity range from 1.0 to ∼1.0×10^{3}  GV, no such particles were found in the data collected by PAMELA between 2006 and 2009. An upper limit on the strangelet flux in cosmic rays was therefore set for particles with charge 1≤Z≤8 and mass 4≤A≤1.2×10^{5}. This limit as a function of mass and as a function of magnetic rigidity allows us to constrain models of SQM production and propagation in the Galaxy.

  20. Combined upper limit on Standard Model Higgs boson production at CDF

    SciTech Connect

    Adrian, Buzatu; /McGill U.

    2012-02-01

    The Higgs boson is the only elementary particle predicted by the Standard Model (SM) that has neither been confirmed nor refuted. The CDF collaboration has performed SM Higgs searches in many channels using p{bar p} collisions at a centre-of-mass energy {radical}s = 1.96 TeV. We present the latest combined Higgs boson search at CDF. Since the previous year's combination, the sensitivity is increased through the addition of new channels, the improvement of existing channels and the addition of new data samples. We also use the latest parton distribution functions and gg {yields} H theoretical cross sections when modelling the signal event yields. Using integrated luminosities of up to 8.2 fb{sup -1}, we observe a good agreement between data and the background prediction. Since we do not see a Higgs boson excess, we set 95% CL upper limits on the Higgs boson cross section in the range between 100 and 200 GeV/c{sup 2}, with 5 GeV/c{sup 2} increments. The observed (expected) limits for a 115 and a 165 GeV/c{sup 2} Higgs boson are 1.55 (1.49) and 0.75 (0.79) x SM, respectively. Since last year, the Higgs boson excluded range by CDF is extended to 156.5 - 173.7 and 100 - 104.5 GeV/c{sup 2}.

  1. Upper limit on the diffuse flux of UHE tau neutrinos from the Pierre Auger Observatory

    SciTech Connect

    Collaboration, The Pierre Auger

    2007-12-01

    The surface detector array of the Pierre Auger Observatory is sensitive to Earth-skimming tau-neutrinos {nu}{sub {tau}} that interact in the Earth's crust. Tau leptons from {tau}{sub {tau}} charged-current interactions can emerge and decay in the atmosphere to produce a nearly horizontal shower with a significant electromagnetic component. The data collected between 1 January 2004 and 31 August 2007 is used to place an upper limit on the diffuse flux of {nu}{sub {tau}} at EeV energies. Assuming an E{sub {nu}}{sup -2} differential energy spectrum the limit set at 90 % C.L. is E{sub {nu}}{sup 2} dN{sub {nu}{sub {tau}}}/dE{sub {nu}} < 1.3 x 10{sup -7} GeV cm{sup -2} s{sup -1} sr{sup -1} in the energy range 2 x 10{sup 17} eV < E{sub {nu}} < 2 x 10{sup 19} eV.

  2. A Method for Calculation of the Upper Limit of Mendeleev's Periodic Table

    NASA Astrophysics Data System (ADS)

    Khazan, Albert

    2010-03-01

    40 years ago some scientists claimed that elements heaviest than No.110 are impossible. The technics got much progress in the last years: element 118 has already been registered. Now, the researchers of Joint Inst. for Nuclear Research (Dubna, Russia) claim that the Periodic Table will end with element 150. However they do not provide theoretical proofs to this claim, because the stability limits of electronic shells they calculated by means of Quantum Mechanics do not answer this question in exact. In contrast, I focused onto the contents of chemical compounds along the Table. The used method is as follows. First, it was found that, given any chemical compound, the contents of any element in it (per 1 gram-atom) is described by the equation of a equilateral hyperbola Y=K/X. Then the scaling coefficient was deduced for the hyperbolas, thus the atomic mass of the last (heaviest) element, 411.66, was found as the abscissa of the ultimate point of the arc drawn by the tops of the hyperbolas. With it, the number of the last element, 155, was found as a consequence. See: Khazan A. Upper Limit in Mendeleev's Periodic Table --- Element No.155. Svenska fysikarkivet, 2009.

  3. The Upper Limit on 3He Fluence in Solar Energetic Particle Events

    NASA Astrophysics Data System (ADS)

    Ho, G. C.; Roelof, E. C.; Mason, G. M.

    2005-03-01

    We investigated 201 3He-rich (3He/4He > 0.004 at 0.2-2.0 MeV nucleon-1) solar energetic particle (SEP) events from 1997 September through 2003 December using the Ultra Low Energy Isotope Spectrometer on the A dvanced Composition E xplorer. Both ``impulsive'' (flare-related) and ``gradual'' (CME-related) events are included. The 3He fluences varied only by a factor of 100 above our instrument sensitivity threshold, while the 4He fluences varied by factor of 10,000 above the same threshold. Moreover, there appears to be no significant correlation between the 3He and 4He fluences. We find it striking that with more than 6 years of continuous SEP data, we could not find any SEP event that has 3He fluence higher than 2.0×105 particles (cm2 sr MeV nucleon-1)-1, while the largest 4He fluence observed was 7.0×107 particles (cm2 sr MeV nucleon-1)-1. To the approximation that the event fluence is to first order proportional the number of particles released from the Sun, the observed upper limit for the 3He fluence seems to indicate that only a limited number of 0.2-2 MeV nucleon-1 3He can be released from the Sun in an SEP event.

  4. Revised upper limit to energy extraction from a Kerr black hole.

    PubMed

    Schnittman, Jeremy D

    2014-12-31

    We present a new upper limit on the energy that may be extracted from a Kerr black hole by means of particle collisions in the ergosphere (i.e., the "collisional Penrose process"). Earlier work on this subject has focused largely on particles with critical values of angular momentum falling into an extremal Kerr black hole from infinity and colliding just outside the horizon. While these collisions are able to reach arbitrarily high center-of-mass energies, it is very difficult for the reaction products to escape back to infinity, effectively limiting the peak efficiency of such a process to roughly 130%. When we allow one of the initial particles to have impact parameter b>2M, and thus not get captured by the horizon, it is able to collide along outgoing trajectories, greatly increasing the chance that the products can escape. For equal-mass particles annihilating to photons, we find a greatly increased peak energy of Eout≈6×Ein. For Compton scattering, the efficiency can go even higher, with Eout≈14×Ein, and for repeated scattering events, photons can both be produced and escape to infinity with Planck-scale energies.

  5. Upper limits for absorption by water vapor in the near-UV

    NASA Astrophysics Data System (ADS)

    Wilson, Eoin M.; Wenger, John C.; Venables, Dean S.

    2016-02-01

    There are few experimental measurements of absorption by water vapor in the near-UV. Here we report the results of spectral measurements of water vapor absorption at ambient temperature and pressure from 325 nm to 420 nm, covering most tropospherically relevant short wavelengths. Spectra were recorded using a broadband optical cavity in the chemically controlled environment of an atmospheric simulation chamber. No absorption attributable to the water monomer (or the dimer) was observed at the 0.5 nm resolution of our system. Our results are consistent with calculated spectra and recent DOAS field observations, but contradict a report of significant water absorption in the near-UV. Based on the detection limit of our instrument, we report upper limits for the water absorption cross section of less than 5×10-26 cm2 molecule-1 at our instrument resolution. For a typical, indicative slant column density of 4×1023 cm2, we calculate a maximum optical depth of 0.02 arising from absorption of water vapor in the atmosphere at wavelengths between 340 nm and 420 nm, with slightly higher maximum optical depths below 340 nm. The results of this work, together with recent atmospheric observations and computational results, suggest that water vapor absorption across most of the near-UV is small compared to visible and infrared wavelengths.

  6. Upper limit on a stochastic background of gravitational waves from seismic measurements in the range 0.05-1 Hz.

    PubMed

    Coughlin, Michael; Harms, Jan

    2014-03-14

    In this Letter, we present an upper limit of ΩGW<1.2×108 on an isotropic stochastic gravitational-wave (GW) background integrated over a year in the frequency range 0.05-1 Hz, which improves current upper limits from high-precision laboratory experiments by about 9 orders of magnitude. The limit is obtained using the response of Earth itself to GWs via a free-surface effect described more than 40 years ago by Dyson. The response was measured by a global network of broadband seismometers selected to maximize the sensitivity. PMID:24679277

  7. Upper limit on a stochastic background of gravitational waves from seismic measurements in the range 0.05-1 Hz.

    PubMed

    Coughlin, Michael; Harms, Jan

    2014-03-14

    In this Letter, we present an upper limit of ΩGW<1.2×108 on an isotropic stochastic gravitational-wave (GW) background integrated over a year in the frequency range 0.05-1 Hz, which improves current upper limits from high-precision laboratory experiments by about 9 orders of magnitude. The limit is obtained using the response of Earth itself to GWs via a free-surface effect described more than 40 years ago by Dyson. The response was measured by a global network of broadband seismometers selected to maximize the sensitivity.

  8. The upper limits of the SNR in radiography and CT with polyenergetic x-rays.

    PubMed

    Shikhaliev, Polad M

    2010-09-21

    The aim of the study is to determine the upper limits of the signal-to-noise ratio (SNR) in radiography and computed tomography (CT) with polyenergetic x-ray sources. In x-ray imaging, monoenergetic x-rays provide a higher SNR compared to polyenergetic x-rays. However, the SNR in polyenergetic x-ray imaging can be increased when a photon-counting detector is used and x-rays are optimally weighted according to their energies. For a particular contrast/background combination and at a fixed x-ray entrance skin exposure, the SNR in energy-weighting x-ray imaging depends on tube voltage and can be maximized by selecting the optimal tube voltage. The SNR in energy-weighted x-ray images acquired at this optimal tube voltage is the highest SNR that can be achieved with polyenergetic x-ray sources. The optimal tube voltages and the highest SNR were calculated and compared to the SNR of monoenergetic x-ray imaging. Monoenergetic, energy-weighting polyenergetic and energy-integrating polyenergetic x-ray imagings were simulated at a fixed entrance skin exposure of 20 mR. The tube voltages varied in the range of 30-140 kVp with 10 kV steps. Contrast elements of CaCO(3), iodine, adipose and tumor with thicknesses of 280 mg cm(-2), 15 mg cm(-2), 1 g cm(-2) and 1 g cm(-2), respectively, inserted in a soft tissue background with 10 cm and 20 cm thicknesses, were used. The energy weighting also improves the contrast-to-noise ratio (CNR) in CT when monoenergetic CT projections are optimally weighted prior to CT reconstruction (projection-based weighting). Alternatively, monoenergetic CT images are reconstructed, optimally weighted and composed to yield a final CT image (image-based weighting). Both projection-based and image-based weighting methods improve the CNR in CT. An analytical approach was used to determine which of these two weighting methods provides the upper limit of the CNR in CT. The energy-weighting method was generalized and expanded as a weighting method applicable

  9. An upper limit on the cosmic-ray luminosity of individual sources from gamma-ray observations

    SciTech Connect

    Supanitsky, A.D.; Souza, V. de E-mail: vitor@ifsc.usp.br

    2013-12-01

    Different types of extragalactic objects are known to produce TeV gamma-rays. Some of these objects are the most probable candidates to accelerate cosmic rays up to 10{sup 20} eV. It is very well known that gamma-rays can be produced as a result of the cosmic ray propagation through the intergalactic medium. These gamma-rays contribute to the total flux observed in the direction of the source. In this paper we propose a new method to derive an upper limit on the cosmic-ray luminosity of an individual source based on the measured upper limit on the integral flux of GeV-TeV gamma-rays. We show how it is possible to calculate an upper limit on the cosmic-ray luminosity of a particular source and we explore the parameter space in which the current GeV-TeV gamma-ray measurements can offer a useful determination. We study in detail two particular sources, Pictor A and NGC 7469, and we calculate the upper limit on the proton luminosity of each source based on the upper limit on the integral gamma-ray flux measured by the H.E.S.S. telescopes.

  10. Upper Limits from Five Years of Blazar Observations with the VERITAS Cherenkov Telescopes

    NASA Astrophysics Data System (ADS)

    Archambault, S.; Archer, A.; Benbow, W.; Bird, R.; Biteau, J.; Buchovecky, M.; Buckley, J. H.; Bugaev, V.; Byrum, K.; Cerruti, M.; Chen, X.; Ciupik, L.; Connolly, M. P.; Cui, W.; Eisch, J. D.; Errando, M.; Falcone, A.; Feng, Q.; Finley, J. P.; Fleischhack, H.; Fortin, P.; Fortson, L.; Furniss, A.; Gillanders, G. H.; Griffin, S.; Grube, J.; Gyuk, G.; Hütten, M.; Håkansson, N.; Hanna, D.; Holder, J.; Humensky, T. B.; Johnson, C. A.; Kaaret, P.; Kar, P.; Kelley-Hoskins, N.; Kertzman, M.; Kieda, D.; Krause, M.; Krennrich, F.; Kumar, S.; Lang, M. J.; Maier, G.; McArthur, S.; McCann, A.; Meagher, K.; Moriarty, P.; Mukherjee, R.; Nguyen, T.; Nieto, D.; O'Faoláin de Bhróithe, A.; Ong, R. A.; Otte, A. N.; Park, N.; Perkins, J. S.; Pichel, A.; Pohl, M.; Popkow, A.; Pueschel, E.; Quinn, J.; Ragan, K.; Reynolds, P. T.; Richards, G. T.; Roache, E.; Rovero, A. C.; Santander, M.; Sembroski, G. H.; Shahinyan, K.; Smith, A. W.; Staszak, D.; Telezhinsky, I.; Tucci, J. V.; Tyler, J.; Vincent, S.; Wakely, S. P.; Weiner, O. M.; Weinstein, A.; Williams, D. A.; Zitzer, B.; VERITAS Collaboration; Fumagalli, M.; Prochaska, J. X.

    2016-06-01

    Between the beginning of its full-scale scientific operations in 2007 and 2012, the VERITAS Cherenkov telescope array observed more than 130 blazars; of these, 26 were detected as very-high-energy (VHE; E > 100 GeV) γ-ray sources. In this work, we present the analysis results of a sample of 114 undetected objects. The observations constitute a total live-time of ˜570 hr. The sample includes several unidentified Fermi-Large Area Telescope (LAT) sources (located at high Galactic latitude) as well as all the sources from the second Fermi-LAT catalog that are contained within the field of view of the VERITAS observations. We have also performed optical spectroscopy measurements in order to estimate the redshift of some of these blazars that do not have spectroscopic distance estimates. We present new optical spectra from the Kast instrument on the Shane telescope at the Lick observatory for 18 blazars included in this work, which allowed for the successful measurement or constraint on the redshift of four of them. For each of the blazars included in our sample, we provide the flux upper limit in the VERITAS energy band. We also study the properties of the significance distributions and we present the result of a stacked analysis of the data set, which shows a 4σ excess.

  11. IRAS-based whole-sky upper limit on Dyson Spheres

    SciTech Connect

    Carrigan, Richard A., Jr.; /Fermilab

    2008-09-01

    A Dyson Sphere is a hypothetical construct of a star purposely cloaked by a thick swarm of broken-up planetary material to better utilize all of the stellar energy. A clean Dyson Sphere identification would give a significant signature for intelligence at work. A search for Dyson Spheres has been carried out using the 250,000 source database of the IRAS infrared satellite which covered 96% of the sky. The search has used the Calgary data collection of the IRAS Low Resolution Spectrometer (LRS) to look for fits to blackbody spectra. Searches have been conducted for both pure (fully cloaked) and partial Dyson Spheres in the blackbody temperature region 100 {le} T {le} 600 K. Other stellar signatures that resemble a Dyson Sphere are reviewed. When these signatures are used to eliminate sources that mimic Dyson Spheres very few candidates remain and even these are ambiguous. Upper limits are presented for both pure and partial Dyson Spheres. The sensitivity of the LRS was enough to find solar-sized Dyson Spheres out to 300 pc, a reach that encompasses a million solar-type stars.

  12. Upper Limits for Power Yield in Thermal, Chemical, and Electrochemical Systems

    NASA Astrophysics Data System (ADS)

    Sieniutycz, Stanislaw

    2010-03-01

    We consider modeling and power optimization of energy converters, such as thermal, solar and chemical engines and fuel cells. Thermodynamic principles lead to expressions for converter's efficiency and generated power. Efficiency equations serve to solve the problems of upgrading or downgrading a resource. Power yield is a cumulative effect in a system consisting of a resource, engines, and an infinite bath. While optimization of steady state systems requires using the differential calculus and Lagrange multipliers, dynamic optimization involves variational calculus and dynamic programming. The primary result of static optimization is the upper limit of power, whereas that of dynamic optimization is a finite-rate counterpart of classical reversible work (exergy). The latter quantity depends on the end state coordinates and a dissipation index, h, which is the Hamiltonian of the problem of minimum entropy production. In reacting systems, an active part of chemical affinity constitutes a major component of the overall efficiency. The theory is also applied to fuel cells regarded as electrochemical flow engines. Enhanced bounds on power yield follow, which are stronger than those predicted by the reversible work potential.

  13. Upper limit of urea adduct formation with methyl esters of n-monocarboxylic acids

    SciTech Connect

    Matsihev, V.A.

    1984-03-01

    This article attempts to determine the temperature of the upper limit of urea formation (ULA) with methyl esters as a function of the number of carbon atoms in their molecules; the ULA temperature of these same esters in binary mixtures with esters of lower molecular weight as a function of the weight concentration of the latter; and the ULA temperature of esters in multicomponent mixtures with esters of lower molecular weight as a function of their partial weight concentrations. Binary mixtures of the esters were investigated with concentrations of the second component (ester with lower molecular weight) of 0-99% by weight, using the same reactants as those used in investigating the original compounds. The dependence of the ULA temperature of the primary component of the binary mixture on the weight concentration of the secondary component is described by a nonlinear equation. The results show that compounds of any homologous series having a normal aliphatic chain, with an interval of carbon numbers that is strictly determined for each such series, from adducts with crystalline urea in accordance with identical laws for individual compounds, binary mixtures, and multicomponent mixtures. Includes 2 tables.

  14. A new upper limit to the field‐aligned potential near Titan

    PubMed Central

    Wellbrock, Anne; Waite, J. Hunter; Jones, Geraint H.

    2015-01-01

    Abstract Neutral particles dominate regions of the Saturn magnetosphere and locations near several of Saturn's moons. Sunlight ionizes neutrals, producing photoelectrons with characteristic energy spectra. The Cassini plasma spectrometer electron spectrometer has detected photoelectrons throughout these regions, where photoelectrons may be used as tracers of magnetic field morphology. They also enhance plasma escape by setting up an ambipolar electric field, since the relatively energetic electrons move easily along the magnetic field. A similar mechanism is seen in the Earth's polar wind and at Mars and Venus. Here we present a new analysis of Titan photoelectron data, comparing spectra measured in the sunlit ionosphere at ~1.4 Titan radii (R T) and at up to 6.8 R T away. This results in an upper limit on the potential of 2.95 V along magnetic field lines associated with Titan at up to 6.8 R T, which is comparable to some similar estimates for photoelectrons seen in Earth's magnetosphere.

  15. A new upper limit to the field‐aligned potential near Titan

    PubMed Central

    Wellbrock, Anne; Waite, J. Hunter; Jones, Geraint H.

    2015-01-01

    Abstract Neutral particles dominate regions of the Saturn magnetosphere and locations near several of Saturn's moons. Sunlight ionizes neutrals, producing photoelectrons with characteristic energy spectra. The Cassini plasma spectrometer electron spectrometer has detected photoelectrons throughout these regions, where photoelectrons may be used as tracers of magnetic field morphology. They also enhance plasma escape by setting up an ambipolar electric field, since the relatively energetic electrons move easily along the magnetic field. A similar mechanism is seen in the Earth's polar wind and at Mars and Venus. Here we present a new analysis of Titan photoelectron data, comparing spectra measured in the sunlit ionosphere at ~1.4 Titan radii (R T) and at up to 6.8 R T away. This results in an upper limit on the potential of 2.95 V along magnetic field lines associated with Titan at up to 6.8 R T, which is comparable to some similar estimates for photoelectrons seen in Earth's magnetosphere. PMID:27609997

  16. Growth dynamics of the seagrass Zostera japonica at its upper and lower distributional limits in the intertidal zone

    NASA Astrophysics Data System (ADS)

    Kim, Jong-Hyeob; Kim, Seung Hyeon; Kim, Young Kyun; Park, Jung-Im; Lee, Kun-Seop

    2016-06-01

    The seagrass Zostera japonica occurs mainly in the intertidal zone and is thus exposed to widely varying environmental conditions affecting its growth and distribution compared to subtidal seagrasses. The growth dynamics of Z. japonica at its upper and lower distributional limits in the intertidal zone were investigated in Koje Bay on the southern coast of Korea to examine the environmental stresses and limiting factors on the growth of intertidal seagrasses. The shoot density and morphology, biomass, and leaf productivity of Z. japonica were measured in relation to coincident measurements of environmental factors at its upper and lower distributional limits and in an intermediate zone of the intertidal area. The mean exposure time to the atmosphere during low tide in the upper intertidal zone was approximately 1.5- and 1.9-fold longer than that in the intermediate and lower intertidal zones, respectively. Shoot density and biomass were significantly higher in the intermediate zone than at the upper and lower distributional limits. Longer emersion leading to a various of environmental stresses appeared to reduce Z. japonica growth in the upper intertidal zone, whereas interspecific competitive interactions related to irradiance seemed to affect Z. japonica growth in the lower intertidal zone. Shoot size, density, biomass, and leaf productivity were lower in the upper than in the lower zone, implying that emersion-associated stresses in the upper zone had a greater detrimental effect on Z. japonica growth than did stresses occurring in the lower zone. The productivity of Z. japonica showed strong positive correlations with air and water temperature, suggesting enhancement of Z. japonica production at higher temperatures. Thus, the predicted increases in air and water temperature associated with global climate change might have positive effects on the growth and extension in distributional range of this species.

  17. Final Report - Inspection Limit Confirmation for Upper Head Penetration Nozzle Cracking

    SciTech Connect

    Anderson, Michael T.; Rudland, David L.; Zhang, Tao; Wilkowski, Gery M.

    2008-08-22

    The ASME Code Case N-729-1 defines alternative examination requirements for the Control Rod Drive Mechanism (CRDM) upper head penetration nozzle welds. The basis for these examination requirements was developed as part of an Industry program conducted by the Materials Reliability Program (MRP) through the Electric Power Research Institute (EPRI). The results of this program were published in MRP-95 Rev. 1 and document a set of finite element weld residual stress analyses conducted on a variety of upper head penetration nozzles. The inspection zone selected by the industry was based on the stress where it was assumed that primary water stress corrosion cracking (PWSCC) would not initiate. As explained in MRP-95 Rev. 1, it has been illustrated that PWSCC does not occur in the Alloy 600 tube when the stresses are below the yield strength of that tube. Typical yield strengths at operating conditions for Alloy 600 range from 35 ksi to 65 ksi. A stress less than 20-ksi tension was chosen as a conservative range where PWSCC would not initiate. Over the last several years, Engineering Mechanics Corporation of Columbus (Emc2) has conducted welding residual stress analyses on upper head penetration J-welds made from Alloy 182 weld metal for the U.S. Nuclear Regulatory Commission (NRC) staff. These efforts were performed as a confirmatory evaluation of the industry’s analyses conducted as part of their MRP-95 Rev. 1 effort. To this point, the analyses conducted by Emc2 have not been compared to the MRP-95 Rev. 1 results or the examination zones defined in the Code Case. Therefore, this report summarizes the past Emc2 CRDM welding analyses and investigates the regions where the welding stresses may be sufficiently high to promote stress corrosion cracking (SCC). In all, 90 welding residual stress analyses were conducted by Emc2 and the largest distance below the weld where the stress drops below 20 ksi was 5 inches for the uphill weld of the 53-degree nozzle case. For the

  18. Upper limits for a lunar dust exosphere from far-ultraviolet spectroscopy by LRO/LAMP

    NASA Astrophysics Data System (ADS)

    Feldman, Paul D.; Glenar, David A.; Stubbs, Timothy J.; Retherford, Kurt D.; Randall Gladstone, G.; Miles, Paul F.; Greathouse, Thomas K.; Kaufmann, David E.; Parker, Joel Wm.; Alan Stern, S.

    2014-05-01

    Since early 2012, the Lyman-Alpha Mapping Project (LAMP) far-ultraviolet spectrograph on the Lunar Reconnaissance Orbiter (LRO) spacecraft has carried out a series of limb observations from within lunar shadow to search for the presence of a high altitude dust exosphere via forward-scattering of sunlight from dust grains. Bright “horizon-glow” was observed from orbit during several Apollo missions and interpreted in terms of dust at altitudes of several km and higher. However, no confirmation of such an exosphere has been made since that time. This raises basic questions about the source(s) of excess brightness in the early measurements and also the conditions for producing observable dust concentrations at km altitudes and higher. Far-ultraviolet measurements between 170 and 190 nm, near the LAMP long wavelength cutoff, are especially sensitive to scattering by small (0.1-0.2 μm radius) dust grains, since the scattering cross-section is near-maximum, and the solar flux is rising rapidly with wavelength. An additional advantage of ultraviolet measurements is the lack of interference by background zodiacal light which must be taken into account at longer wavelengths. As of July 2013, LAMP has completed several limb-observing sequences dedicated to the search for horizon glow, but no clear evidence of dust scattering has yet been obtained. Upper limits for vertical dust column abundance have been estimated at less than 10 grains cm-2 (0.1 μm grain radius), by comparing the measured noise-equivalent brightness with the results of Mie scattering simulations for the same observing geometries. These results indicate that Lunar Atmosphere Dust Environment Explorer (LADEE) UVS lunar dust observations will be considerably more challenging than planned.

  19. Upper limit to magnetism in LaAlO3/SrTiO3 heterostructures

    NASA Astrophysics Data System (ADS)

    Fitzsimmons, Michael

    2012-02-01

    In 2004 Ohtomo and Hwang reported unusually high conductivity in LaAlO3 and SrTiO3 bilayer samples. Since then, metallic conduction, superconductivity, magnetism, and coexistence of superconductivity and ferromagnetism have been attributed to LaAlO3/SrTiO3 interfaces. Very recently, two studies have reported large magnetic moments attributed to interfaces from measurement techniques that are unable to distinguish between interfacial and bulk magnetism. Consequently, it is imperative to perform magnetic measurements that by being intrinsically sensitive to interface magnetism are impervious to experimental artifacts suffered by bulk measurements. Using polarized neutron reflectometry, we measured the neutron spin dependent reflectivity from four LaAlO3/SrTiO3 superlattices. Our results indicate the upper limit for the magnetization averaged over the lateral dimensions of the sample induced by an 11 T magnetic field at 1.7 K is less than 2 G. SQUID magnetometry of the neutron superlattice samples sporadically finds an enhanced moment (consistent with past reports), possibly due to experimental artifacts. These observations set important restrictions on theories which imply a strongly enhanced magnetism at the interface between LaAlO3 and SrTiO3. Work performed in collaboration with N.W. Hengartner, S. Singh, M. Zhernenkov (LANL), F.Y. Bruno, J. Santamaria (Universidad Complutense de Madrid), A. Brinkman, M.J.A. Huijben, H. Molegraaf (MESA+ Institute for Nanotechnology), J. de la Venta and Ivan K. Schuller (UCSD). [4pt] Work supported by the Office of Basic Energy Science, U.S. Department of Energy, BES-DMS and DMR under grant DE FG03-87ER-45332. Work at UCM is supported by Consolider Ingenio CSD2009-00013 (IMAGINE), CAM S2009-MAT 1756 (PHAMA) and work at Twente is supported by the Foundation for Fundamental Research on Matter (FOM).

  20. Upper Limits of Normal for Alanine Aminotransferase Activity in the United States Population

    PubMed Central

    Ruhl, Constance E.; Everhart, James E.

    2011-01-01

    Background & Rationale Alanine aminotransferase (ALT) is an important test for liver disease, yet there is no generally accepted upper limit of normal (ULN) in the United States. Furthermore, the ability of ALT to differentiate persons with and without liver disease is uncertain. We examined cut-offs for ALT for their ability to discriminate between persons with positive hepatitis C virus (HCV) RNA and those at low risk for liver injury in the U.S. population. Methods Among adult participants in the 1999–2008 U.S. National Health and Nutrition Examination Survey, 259 were positive for serum HCV RNA and 3,747 were at low risk for liver injury (negative HCV RNA and hepatitis B surface antigen, low alcohol consumption, no evidence of diabetes, normal body mass index and waist circumference). Serum ALT activity was measured centrally. Results Maximum correct classification was achieved at ALT=29 IU/L for men (88% sensitivity, 83% specificity) and 22 (89% sensitivity, 82% specificity) for women. The cut-off for 95% sensitivity was an ALT=24 IU/L (70% specificity) for men and 18 (63% specificity) for women. The cut-off for 95% specificity was an ALT=44 IU/L (64% sensitivity) for men and 32 (59% sensitivity) for women. The area under the curve was 0.929 for men and 0.915 for women. If the cut-offs with the best correct classification were applied to the entire population, 36.4% of men and 28.3% of women would have had abnormal ALT. Conclusion ALT discriminates persons infected with HCV from those at low risk of liver disease, but would be considered elevated in a large proportion of the U.S. population. PMID:21987480

  1. Age-related upper limits of normal for maximum upright exercise pulmonary haemodynamics.

    PubMed

    Oliveira, Rudolf K F; Agarwal, Manyoo; Tracy, Julie A; Karin, Abbey L; Opotowsky, Alexander R; Waxman, Aaron B; Systrom, David M

    2016-04-01

    The exercise definition of pulmonary hypertension was eliminated from the pulmonary hypertension guidelines in part due to uncertainty of the upper limits of normal (ULNs) for exercise haemodynamics in subjects >50 years old.The present study, therefore, evaluated the pulmonary haemodynamic responses to maximum upright incremental cycling exercise in consecutive subjects who underwent an invasive cardiopulmonary exercise testing for unexplained exertional intolerance, deemed normal based on preserved exercise capacity and normal resting supine haemodynamics. Subjects aged >50 years old (n=41) were compared with subjects ≤50 years old (n=25). ULNs were calculated as mean + 2 sdPeak exercise mean pulmonary arterial pressure was not different for subjects >50 and ≤50 years old (23 ± 5 versus 22 ± 4 mmHg, p=0.22), with ULN of 33 and 30 mmHg, respectively. Peak cardiac output was lower in older subjects (median (interquartile range): 12.1 (9.4-14.2)versus16.2 (13.8-19.2) L·min(-1), p<0.001). Peak pulmonary vascular resistance was higher in older subjects compared with younger subjects (mean ± sd: 1.20 ± 0.45 versus 0.82 ± 0.26 Wood units, p<0.001), with ULN of 2.10 and 1.34 Wood units, respectively.We observed that subjects >50 and ≤ 50 years old have different pulmonary vascular responses to exercise. Older subjects have higher pulmonary vascular resistance at peak exercise, resulting in different exercise haemodynamics ULNs compared with the younger population.

  2. Interfacially polymerized layers for oxygen enrichment: a method to overcome Robeson's upper-bound limit.

    PubMed

    Tsai, Ching-Wei; Tsai, Chieh; Ruaan, Ruoh-Chyu; Hu, Chien-Chieh; Lee, Kueir-Rarn

    2013-06-26

    Interfacial polymerization of four aqueous phase monomers, diethylenetriamine (DETA), m-phenylenediamine (mPD), melamine (Mela), and piperazine (PIP), and two organic phase monomers, trimethyl chloride (TMC) and cyanuric chloride (CC), produce a thin-film composite membrane of polymerized polyamide layer capable of O2/N2 separation. To achieve maximum efficiency in gas permeance and O2/N2 permselectivity, the concentrations of monomers, time of interfacial polymerization, number of reactive groups in monomers, and the structure of monomers need to be optimized. By controlling the aqueous/organic monomer ratio between 1.9 and 2.7, we were able to obtain a uniformly interfacial polymerized layer. To achieve a highly cross-linked layer, three reactive groups in both the aqueous and organic phase monomers are required; however, if the monomers were arranged in a planar structure, the likelihood of structural defects also increased. On the contrary, linear polymers are less likely to result in structural defects, and can also produce polymer layers with moderate O2/N2 selectivity. To minimize structural defects while maximizing O2/N2 selectivity, the planar monomer, TMC, containing 3 reactive groups, was reacted with the semirigid monomer, PIP, containing 2 reactive groups to produce a membrane with an adequate gas permeance of 7.72 × 10(-6) cm(3) (STP) s(-1) cm(-2) cm Hg(-1) and a high O2/N2 selectivity of 10.43, allowing us to exceed the upper-bound limit of conventional thin-film composite membranes. PMID:23731366

  3. Electroweak absolute, meta-, and thermal stability in neutrino mass models

    NASA Astrophysics Data System (ADS)

    Lindner, Manfred; Patel, Hiren H.; Radovčić, Branimir

    2016-04-01

    We analyze the stability of the electroweak vacuum in neutrino mass models containing right-handed neutrinos or fermionic isotriplets. In addition to considering absolute stability, we place limits on the Yukawa couplings of new fermions based on metastability and thermal stability in the early Universe. Our results reveal that the upper limits on the neutrino Yukawa couplings can change significantly when the top quark mass is allowed to vary within the experimental range of uncertainty in its determination.

  4. Absolute Summ

    NASA Astrophysics Data System (ADS)

    Phillips, Alfred, Jr.

    Summ means the entirety of the multiverse. It seems clear, from the inflation theories of A. Guth and others, that the creation of many universes is plausible. We argue that Absolute cosmological ideas, not unlike those of I. Newton, may be consistent with dynamic multiverse creations. As suggested in W. Heisenberg's uncertainty principle, and with the Anthropic Principle defended by S. Hawking, et al., human consciousness, buttressed by findings of neuroscience, may have to be considered in our models. Predictability, as A. Einstein realized with Invariants and General Relativity, may be required for new ideas to be part of physics. We present here a two postulate model geared to an Absolute Summ. The seedbed of this work is part of Akhnaton's philosophy (see S. Freud, Moses and Monotheism). Most important, however, is that the structure of human consciousness, manifest in Kenya's Rift Valley 200,000 years ago as Homo sapiens, who were the culmination of the six million year co-creation process of Hominins and Nature in Africa, allows us to do the physics that we do. .

  5. Upper limits on the size of satellites of Asteroid (4) Vesta from 2007 Hubble Space Telescope observations

    NASA Astrophysics Data System (ADS)

    McFadden, Lucy A.; Bastien, Fabienne A.; Mutchler, Max; Crow, Carolyn A.; Weir, Heather; Li, Jian-Yang; Hamilton, Douglas P.

    2012-08-01

    We imaged the region around Asteroid (4) Vesta in nine long exposures using the Wide Field Planetary Camera 2 on the Hubble Space Telescope on May 14 and 16, 2007 to conduct a deep search for satellites in support of NASA's Dawn mission that orbited (4) Vesta in 2011-2012. Several previous search efforts have been undertaken, but no satellites were detected. Our search covered distances from 14 to 260 Vesta radii and searched to a limiting magnitude of 22.5 ± 0.4 in HST's wide-band red filter (F702W). Our upper limit for possible satellites corresponds to a satellite just 22 ± 4 m in radius, assuming the same optical properties as Vesta. Our upper limit is ˜10 times smaller than the best limit of previous searches. In situ satellite searches by NASA's Dawn spacecraft will probe regions closer to Vesta than our effort reported here.

  6. Upper limit to antiproton flux in cosmic radiation above 100 GeV using muon charge ratio

    NASA Technical Reports Server (NTRS)

    Stephens, S. A.

    1983-01-01

    Upper limits to the fraction of antiprotons in cosmic radiation have been estimated from the observed charge ratio of muons at sea-level. Using these values, it is shown that constraints can be set on the extragalactic hypothesis of the observed antiprotons in the framework of energy-dependent confinement of cosmic rays in the galaxy.

  7. MAGIC upper limits to the VHE gamma-ray flux of 3C 454.3 in high emission state

    NASA Astrophysics Data System (ADS)

    Anderhub, H.; Antonelli, L. A.; Antoranz, P.; Backes, M.; Baixeras, C.; Balestra, S.; Barrio, J. A.; Bartko, H.; Bastieri, D.; Becerra González, J.; Becker, J. K.; Bednarek, W.; Berger, K.; Bernardini, E.; Biland, A.; Bock, R. K.; Bonnoli, G.; Bordas, P.; Borla Tridon, D.; Bosch-Ramon, V.; Bretz, T.; Britvitch, I.; Camara, M.; Carmona, E.; Commichau, S.; Contreras, J. L.; Cortina, J.; Costado, M. T.; Covino, S.; Curtef, V.; Dazzi, F.; de Angelis, A.; de Cea Del Pozo, E.; de Los Reyes, R.; de Lotto, B.; de Maria, M.; de Sabata, F.; Delgado Mendez, C.; Dominguez, A.; Dorner, D.; Doro, M.; Elsaesser, D.; Errando, M.; Ferenc, D.; Fernández, E.; Firpo, R.; Fonseca, M. V.; Font, L.; Galante, N.; García López, R. J.; Garczarczyk, M.; Gaug, M.; Goebel, F.; Hadasch, D.; Hayashida, M.; Herrero, A.; Höhne-Mönch, D.; Hose, J.; Hsu, C. C.; Huber, S.; Jogler, T.; Kranich, D.; La Barbera, A.; Laille, A.; Leonardo, E.; Lindfors, E.; Lombardi, S.; Longo, F.; López, M.; Lorenz, E.; Majumdar, P.; Maneva, G.; Mankuzhiyil, N.; Mannheim, K.; Maraschi, L.; Mariotti, M.; Martínez, M.; Mazin, D.; Meucci, M.; Meyer, M.; Miranda, J. M.; Mirzoyan, R.; Moldón, J.; Moles, M.; Moralejo, A.; Nieto, D.; Nilsson, K.; Ninkovic, J.; Otte, N.; Oya, I.; Paoletti, R.; Paredes, J. M.; Pasanen, M.; Pascoli, D.; Pauss, F.; Pegna, R. G.; Perez-Torres, M. A.; Persic, M.; Peruzzo, L.; Prada, F.; Prandini, E.; Puchades, N.; Rhode, W.; Ribó, M.; Rico, J.; Rissi, M.; Robert, A.; Rügamer, S.; Saggion, A.; Saito, T. Y.; Salvati, M.; Sanchez-Conde, M.; Sartori, P.; Satalecka, K.; Scalzotto, V.; Scapin, V.; Schweizer, T.; Shayduk, M.; Shinozaki, K.; Shore, S. N.; Sidro, N.; Sierpowska-Bartosik, A.; Sillanpää, A.; Sitarek, J.; Sobczynska, D.; Spanier, F.; Stamerra, A.; Stark, L. S.; Takalo, L.; Tavecchio, F.; Temnikov, P.; Tescaro, D.; Teshima, M.; Tluczykont, M.; Torres, D. F.; Turini, N.; Vankov, H.; Venturini, A.; Vitale, V.; Wagner, R. M.; Wittek, W.; Zabalza, V.; Zandanel, F.; Zanin, R.; Zapatero, J.; Vercellone, S.; Donnarumma, I.; D'Ammando, F.; Tavani, M.

    2009-04-01

    Aims: We report upper limits to the very high energy flux (E>100 GeV) of the flat spectrum radio quasar 3C 454.3 (z=0.859) derived by the Cherenkov telescope MAGIC during the high states of July/August and November/December 2007. We compare the upper limits derived in both time slots with the available quasi-simultaneous MeV-GeV data from the AGILE γ-ray satellite and interpret the observational results in the context of leptonic emission models. Methods: The source was observed with the MAGIC telescope during the active phases of July-August 2007 and November-December 2007 and the data were analyzed with the MAGIC standard analysis tools. For the periods around the ends of July and November, characterized by the most complete multifrequency coverage, we constructed the spectral energy distributions using our data together with nearly simultaneous multifrequency (optical, UV, X-ray and GeV) data. Results: Only upper limits can be derived from the MAGIC data. The upper limits, once corrected for the expected absorption by the extragalactic background light, together with nearly simultaneous multifrequency data, allow us to constrain the spectral energy distribution of 3C 454.3. The data are consistent with the model expectations based on inverse Compton scattering of the ambient photons from the broad line region by relativistic electrons, which robustly predicts a sharp cut-off above 20-30 GeV.

  8. An upper limit to the electrodynamic power output from a thin accretion disk around a black hole

    NASA Technical Reports Server (NTRS)

    Park, Seok Jae; Vishniac, Ethan T.

    1994-01-01

    We examine the electrodynamic power output from a thin accretion disk surrounding a Kerr black hole. We derive an upper limit for the total power. We find that this limit is only moderately sensitive to most of the relativistic correction factors. In fact, this limit is less sensitive to the change in the black hole spin than one would expect from the change in the inner radius of the accretion disk. The disk around a rapidly rotating black hole will produce more nonthermal radiation than a similar disk around a slowly rotating black hole of identical mass, but the difference is only a factor of approximately 1.7.

  9. 42 CFR 447.321 - Outpatient hospital and clinic services: Application of upper payment limits.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Outpatient hospital and clinic services... SERVICES Payment Methods for Other Institutional and Noninstitutional Services Outpatient Hospital and Clinic Services § 447.321 Outpatient hospital and clinic services: Application of upper payment...

  10. Sample Size Limits for Estimating Upper Level Mediation Models Using Multilevel SEM

    ERIC Educational Resources Information Center

    Li, Xin; Beretvas, S. Natasha

    2013-01-01

    This simulation study investigated use of the multilevel structural equation model (MLSEM) for handling measurement error in both mediator and outcome variables ("M" and "Y") in an upper level multilevel mediation model. Mediation and outcome variable indicators were generated with measurement error. Parameter and standard…

  11. Probing the upper limits of current flow in one-dimensional carbon conductors

    NASA Astrophysics Data System (ADS)

    Liao, Albert Daen

    We use breakdown thermometry to study carbon nanotube (CNT) devices and graphene nanoribbons (GNRs) on SiO2 substrates. Experiments and modeling find the CNT-substrate thermal coupling scales proportionally to CNT diameter. Diffuse mismatch modeling (DMM) reveals the upper limit of thermal coupling ˜0.7 WK-1m-1 for the largest diameter (3-4 nm) CNTs. Similarly, we extracted the GNR thermal conductivity (TC), ˜80 (130) Wm-1K-1 at 20 (600) °C across our samples, dominated by phonons, with estimated <10% electronic contribution. The TC of GNRs is an order of magnitude lower than that of micron-sized graphene on SiO2, suggesting strong roles of edge and defect scattering, and the importance of thermal dissipation in small GNR devices. We also compare the peak current density of metallic single-walled CNTs with GNRs. We find that as the "footprint" (width) between such a device and the underlying substrate decreases, heat dissipation becomes more efficient (for a given width), allowing for higher current densities. Because of their smaller dimensions and lack of edges, CNTs can carry larger current densities than GNRs, up to ˜16 mA/mum for an m-SWNT with a diameter of ˜0.7 nm versus ˜3 mA/mum for a GNR having a width of ˜15 nm. Such current densities are the highest possible in any diffusive conductor, to our knowledge. We also study semiconducting and metallic single-walled CNTs under vacuum. Sem-iconducting single-wall CNTs under high electric field stress (˜10 V/mum) display a re-markable current increase due to avalanche generation of free electrons and holes. Unlike in other materials, the avalanche process in such 1D quantum wires involves access to the third subband and is insensitive to temperature, but strongly dependent on diameter ˜exp(-1/d2). Comparison with a theoretical model yields a novel approach to obtain the inelastic optical phonon emission length, lambdaOP,ems ≈ 15 d nm. We find that current in metallic single-walled CNTs does not

  12. Upper limits for stratospheric H2O2 and HOCl from high resolution balloon-borne infrared solar absorption spectra

    NASA Technical Reports Server (NTRS)

    Larsen, J. C.; Rinsland, C. P.; Goldman, A.; Murcray, D. G.; Murcray, F. J.

    1985-01-01

    Solar absorption spectra from two stratospheric balloon flights have been analyzed for the presence of H2O2 and HOCl absorption in the 1230.0 to 1255.0 per cm region. The data were recorded at 0.02 per cm resolution during sunset with the University of Denver interferometer system on October 27, 1978 and March 23, 1981. Selected spectral regions were analyzed with the technique of nonlinear least squares spectral curve fitting. Upper limits of 0.33 ppbv for H2O2 and 0.36 ppbv for HOCl near 28 km are derived from the 1978 flight data while upper limits of 0.44 ppbv for H2O2 and 0.43 ppbv for HOCl at 29.5 km are obtained from the 1981 flight data.

  13. Upper Limits on the VHE Gamma-Ray Emission from the Willman 1 Satellite Galaxy with the Magic Telescope

    NASA Astrophysics Data System (ADS)

    Aliu, E.; Anderhub, H.; Antonelli, L. A.; Antoranz, P.; Backes, M.; Baixeras, C.; Balestra, S.; Barrio, J. A.; Bartko, H.; Bastieri, D.; González, J. Becerra; Becker, J. K.; Bednarek, W.; Berger, K.; Bernardini, E.; Biland, A.; Bock, R. K.; Bonnoli, G.; Bordas, P.; Tridon, D. Borla; Bosch-Ramon, V.; Bose, D.; Bretz, T.; Britvitch, I.; Camara, M.; Carmona, E.; Commichau, S.; Contreras, J. L.; Cortina, J.; Costado, M. T.; Covino, S.; Curtef, V.; Dazzi, F.; DeAngelis, A.; DeCea del Pozo, E.; de los Reyes, R.; DeLotto, B.; DeMaria, M.; DeSabata, F.; Mendez, C. Delgado; Dominguez, A.; Dorner, D.; Doro, M.; Elsaesser, D.; Errando, M.; Ferenc, D.; Fernández, E.; Firpo, R.; Fonseca, M. V.; Font, L.; Galante, N.; García López, R. J.; Garczarczyk, M.; Gaug, M.; Goebel, F.; Hadasch, D.; Hayashida, M.; Herrero, A.; Höhne-Mönch, D.; Hose, J.; Hsu, C. C.; Huber, S.; Jogler, T.; Kranich, D.; Barbera, A. La; Laille, A.; Leonardo, E.; Lindfors, E.; Lombardi, S.; Longo, F.; López, M.; Lorenz, E.; Majumdar, P.; Maneva, G.; Mankuzhiyil, N.; Mannheim, K.; Maraschi, L.; Mariotti, M.; Martínez, M.; Mazin, D.; Meucci, M.; Meyer, M.; Miranda, J. M.; Mirzoyan, R.; Moldón, J.; Moles, M.; Moralejo, A.; Nieto, D.; Nilsson, K.; Ninkovic, J.; Otte, N.; Oya, I.; Paoletti, R.; Paredes, J. M.; Pasanen, M.; Pascoli, D.; Pauss, F.; Pegna, R. G.; Perez-Torres, M. A.; Persic, M.; Peruzzo, L.; Prada, F.; Prandini, E.; Puchades, N.; Rhode, W.; Ribó, M.; Rico, J.; Rissi, M.; Robert, A.; Rügamer, S.; Saggion, A.; Saito, T. Y.; Salvati, M.; Sanchez-Conde, M.; Satalecka, K.; Scalzotto, V.; Scapin, V.; Schweizer, T.; Shayduk, M.; Shinozaki, K.; Shore, S. N.; Sidro, N.; Sierpowska-Bartosik, A.; Sillanpää, A.; Sitarek, J.; Sobczynska, D.; Spanier, F.; Stamerra, A.; Stark, L. S.; Takalo, L.; Tavecchio, F.; Temnikov, P.; Tescaro, D.; Teshima, M.; Tluczykont, M.; Torres, D. F.; Turini, N.; Vankov, H.; Wagner, R. M.; Wittek, W.; Zabalza, V.; Zandanel, F.; Zanin, R.; Zapatero, J.

    2009-06-01

    We present the result of the observation of the ultrafaint dwarf galaxy Willman 1 performed with the 17 m MAGIC telescope during 15.5 hr between March and May 2008. No significant γ-ray emission was found. We derived upper limits of the order of 10-12 ph cm-2 s-1 on the integral flux above 100 GeV, which we compare with predictions from several of the established neutralino benchmark models in the mSUGRA parameter space. The neutralino annihilation spectra are defined after including the recently quantified contribution of internal bremsstrahlung from the virtual sparticles that mediate the annihilation. Flux boost factors of three orders of magnitude are required even in the most optimistic scenario to match our upper limits. However, uncertainties in the dark matter intrinsic and extrinsic properties (e.g., presence of substructures, Sommerfeld effect) may significantly reduce this gap.

  14. Flux upper limits for 47 AGN observed with H.E.S.S. in 2004-2011

    NASA Astrophysics Data System (ADS)

    H.E.S.S. Collaboration; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Angüner, E.; Anton, G.; Balenderan, S.; Balzer, A.; Barnacka, A.; Becherini, Y.; Becker Tjus, J.; Bernlöhr, K.; Birsin, E.; Bissaldi, E.; Biteau, J.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Brucker, J.; Brun, F.; Brun, P.; Bulik, T.; Carrigan, S.; Casanova, S.; Cerruti, M.; Chadwick, P. M.; Chalme-Calvet, R.; Chaves, R. C. G.; Cheesebrough, A.; Chrétien, M.; Colafrancesco, S.; Cologna, G.; Conrad, J.; Couturier, C.; Cui, Y.; Dalton, M.; Daniel, M. K.; Davids, I. D.; Degrange, B.; Deil, C.; deWilt, P.; Dickinson, H. J.; Djannati-Ataï, A.; Domainko, W.; Drury, L. O.'C.; Dubus, G.; Dutson, K.; Dyks, J.; Dyrda, M.; Edwards, T.; Egberts, K.; Eger, P.; Espigat, P.; Farnier, C.; Fegan, S.; Feinstein, F.; Fernandes, M. V.; Fernandez, D.; Fiasson, A.; Fontaine, G.; Förster, A.; Füßling, M.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Grondin, M.-H.; Grudzińska, M.; Häffner, S.; Hahn, J.; Harris, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hillert, A.; Hinton, J. A.; Hofmann, W.; Hofverberg, P.; Holler, M.; Horns, D.; Jacholkowska, A.; Jahn, C.; Jamrozy, M.; Janiak, M.; Jankowsky, F.; Jung, I.; Kastendieck, M. A.; Katarzyński, K.; Katz, U.; Kaufmann, S.; Khélifi, B.; Kieffer, M.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kneiske, T.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Krayzel, F.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lefaucheur, J.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Lennarz, D.; Lohse, T.; Lopatin, A.; Lu, C.-C.; Marandon, V.; Marcowith, A.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; McComb, T. J. L.; Méhault, J.; Meintjes, P. J.; Menzler, U.; Meyer, M.; Moderski, R.; Mohamed, M.; Moulin, E.; Murach, T.; Naumann, C. L.; de Naurois, M.; Niemiec, J.; Nolan, S. J.; Oakes, L.; Ohm, S.; de Oña Wilhelmi, E.; Opitz, B.; Ostrowski, M.; Oya, I.; Panter, M.; Parsons, R. D.; Paz Arribas, M.; Pekeur, N. W.; Pelletier, G.; Perez, J.; Petrucci, P.-O.; Peyaud, B.; Pita, S.; Poon, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Raue, M.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Rieger, F.; Rob, L.; Romoli, C.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Sanchez, D. A.; Santangelo, A.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwarzburg, S.; Schwemmer, S.; Sol, H.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stinzing, F.; Stycz, K.; Sushch, I.; Szostek, A.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tluczykont, M.; Trichard, C.; Valerius, K.; van Eldik, C.; van Soelen, B.; Vasileiadis, G.; Venter, C.; Viana, A.; Vincent, P.; Völk, H. J.; Volpe, F.; Vorster, M.; Vuillaume, T.; Wagner, S. J.; Wagner, P.; Ward, M.; Weidinger, M.; Weitzel, Q.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Zabalza, V.; Zacharias, M.; Zajczyk, A.; Zdziarski, A. A.; Zech, A.; Zechlin, H.-S.

    2014-04-01

    Context. About 40% of the observation time of the High Energy Stereoscopic System (H.E.S.S.) is dedicated to studying active galactic nuclei (AGN), with the aim of increasing the sample of known extragalactic very-high-energy (VHE, E > 100 GeV) sources and constraining the physical processes at play in potential emitters. Aims: H.E.S.S. observations of AGN, spanning a period from April 2004 to December 2011, are investigated to constrain their γ-ray fluxes. Only the 47 sources without significant excess detected at the position of the targets are presented. Methods: Upper limits on VHE fluxes of the targets were computed and a search for variability was performed on the nightly time scale. Results: For 41 objects, the flux upper limits we derived are the most constraining reported to date. These constraints at VHE are compared with the flux level expected from extrapolations of Fermi-LAT measurements in the two-year catalog of AGN. The H.E.S.S. upper limits are at least a factor of two lower than the extrapolated Fermi-LAT fluxes for 11 objects. Taking into account the attenuation by the extragalactic background light reduces the tension for all but two of them, suggesting intrinsic curvature in the high-energy spectra of these two AGN. Conclusions: Compilation efforts led by current VHE instruments are of critical importance for target-selection strategies before the advent of the Cherenkov Telescope Array (CTA).

  15. FDG-PET/CT Limited to the Thorax and Upper Abdomen for Staging and Management of Lung Cancer

    PubMed Central

    Postema, Jan W. A.; Schreurs, Wendy M. J.; Lafeber, Albert; Hendrickx, Baudewijn W.; Oyen, Wim J. G.; Vogel, Wouter V.

    2016-01-01

    Purpose This study evaluates the diagnostic accuracy of [F-18]-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) of the chest/upper abdomen compared to the generally performed scan from head to upper thighs, for staging and management of (suspected) lung cancer in patients with no history of malignancy or complaints outside the thorax. Methods FDG-PET/CT scans of 1059 patients with suspected or recently proven lung cancer, with no history of malignancy or complaints outside the thorax, were analysed in a retrospective multi-centre trial. Suspect FDG-avid lesions in the chest and upper abdomen, the head and neck area above the shoulder line and in the abdomen and pelvis below the caudal tip of the liver were noted. The impact of lesions detected in the head and neck area and abdomen and pelvis on additional diagnostic procedures, staging and treatment decisions was evaluated. Results The head and neck area revealed additional suspect lesions in 7.2%, and the abdomen and pelvis in 15.8% of patients. Imaging of the head and neck area and the abdomen and pelvic area showed additional lesions in 19.5%, inducing additional diagnostic procedures in 7.8%. This resulted in discovery of additional lesions considered malignant in 10.7%, changing patient management for lung cancer in 1.2%. In (suspected) lung cancer, PET/CT limited to the chest and upper abdomen resulted in correct staging in 98.7% of patients, which led to the identical management as full field of view PET in 98.8% of patients. Conclusion High value of FDG-PET/CT for staging and correct patient management is already achieved with chest and upper abdomen. Findings in head and neck area and abdomen and pelvis generally induce investigations with limited or no impact on staging and treatment of NSCLC, and can be interpreted accordingly. PMID:27556809

  16. Increases in the evolutionary potential of upper thermal limits under warmer temperatures in two rainforest Drosophila species.

    PubMed

    van Heerwaarden, Belinda; Malmberg, Michelle; Sgrò, Carla M

    2016-02-01

    Tropical and subtropical species represent the majority of biodiversity. These species are predicted to lack the capacity to evolve higher thermal limits in response to selection imposed by climatic change. However, these assessments have relied on indirect estimates of adaptive capacity, using conditions that do not reflect environmental changes projected under climate change. Using a paternal half-sib full-sib breeding design, we estimated the additive genetic variance and narrow-sense heritability for adult upper thermal limits in two rainforest-restricted species of Drosophila reared under two thermal regimes, reflecting increases in seasonal temperature projected for the Wet Tropics of Australia and under standard laboratory conditions (constant 25°C). Estimates of additive genetic variation and narrow-sense heritability for adult heat tolerance were significantly different from zero in both species under projected summer, but not winter or constant, thermal regimes. In contrast, significant broad-sense genetic variation was apparent in all thermal regimes for egg-to-adult viability. Environment-dependent changes in the expression of genetic variation for adult upper thermal limits suggest that predicting adaptive responses to climate change will be difficult. Estimating adaptive capacity under conditions that do not reflect future environmental conditions may provide limited insight into evolutionary responses to climate change.

  17. EGRET upper limits to the high-energy gamma-ray emission from the millisecond pulsars in nearby globular clusters

    NASA Technical Reports Server (NTRS)

    Michelson, P. F.; Bertsch, D. L.; Brazier, K.; Chiang, J.; Dingus, B. L.; Fichtel, C. E.; Fierro, J.; Hartman, R. C.; Hunter, S. D.; Kanbach, G.

    1994-01-01

    We report upper limits to the high-energy gamma-ray emission from the millisecond pulsars (MSPs) in a number of globular clusters. The observations were done as part of an all-sky survey by the energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory (CGRO) during Phase I of the CGRO mission (1991 June to 1992 November). Several theoretical models suggest that MSPs may be sources of high-energy gamma radiation emitted either as primary radiation from the pulsar magnetosphere or as secondary radiation generated by conversion into photons of a substantial part of the relativistic e(+/-) pair wind expected to flow from the pulsar. To date, no high-energy emission has been detected from an individual MSP. However, a large number of MSPs are expected in globular cluster cores where the formation rate of accreting binary systems is high. Model predictions of the total number of pulsars range in the hundreds for some clusters. These expectations have been reinforced by recent discoveries of a substantial number of radio MSPs in several clusters; for example, 11 have been found in 47 Tucanae (Manchester et al.). The EGRET observations have been used to obtain upper limits for the efficiency eta of conversion of MSP spin-down power into hard gamma rays. The upper limits are also compared with the gamma-ray fluxes predicted from theoretical models of pulsar wind emission (Tavani). The EGRET limits put significant constraints on either the emission models or the number of pulsars in the globular clusters.

  18. New upper limits of a braneworld model with recent Solar System tests

    NASA Astrophysics Data System (ADS)

    Deng, Xue-Mei; Xie, Yi

    2016-01-01

    As an extension of previous works on classical tests of a braneworld model which is called as the Dadhich, Maartens, Papadopoulos and Rezania (DMPR) solution, and as an attempt to find more stringent constraints on this model, we investigate its effects on physical experiments and astronomical observations conducted in the Solar System by modeling new observable effects and adopting new datasets. First, we investigate gravitational time delay at inferior conjunction (IC) caused by the braneworld model, which was not considered in previous works, because these measurements are not affected by the solar corona noise. Second, the Cassini superior conjunction (SC) experiment is, for the first time, used to test the DMPR model. Third, compared to previous works, we refine the model, which confronts the perihelion shift induced by the braneworld model with modern Solar System ephemerides INPOP10a (IMCCE, France) and EPM2011 (IAA RAS, Russia). The correction of DMPR solution to Einstein’s general relativity (GR) in the four-dimensional spacetime can be characterized by a constant bulk “tidal charge” parameter Q, which is confined in the present work. We find that time delay experiment at IC is independent of Q and not suitable for testing the braneworld model. However, the Cassini SC experiment and modern Solar System ephemerides can give better upper bounds on Q: (1) |Q|≤ 1.2 × 107m2 by Cassini, and (2) |Q|≤ 61m2 based on the supplementary advances of the perihelia provided by INPOP10a and |Q|≤ 3.0 × 102m2 based on the ones of EPM2011. The latter upper bounds are improved to be tighter than the ones of previous works by at least two orders of magnitude. Besides, the stronger constraints on the brane tension are given by the modern ephemerides, which are λ ≥ 3.1 × 105MeV4 for INPOP10a and λ ≥ 6.2 × 104MeV4 for EPM2011. These improved upper bounds mean that the Solar System tests can serve as a good testbed for high dimensional theories.

  19. Increasing the Upper Temperature Oxidation Limit of Alumina Forming Austenitic Stainless Steels in Air with Water Vapor

    SciTech Connect

    Brady, Michael P; Unocic, Kinga A; Lance, Michael J; Santella, Michael L; Yamamoto, Yukinori; Walker, Larry R

    2011-01-01

    A family of alumina-forming austenitic (AFA) stainless steels is under development for use in aggressive oxidizing conditions from {approx}600-900 C. These alloys exhibit promising mechanical properties but oxidation resistance in air with water vapor environments is currently limited to {approx}800 C due to a transition from external protective alumina scale formation to internal oxidation of aluminum with increasing temperature. The oxidation behavior of a series of AFA alloys was systematically studied as a function of Cr, Si, Al, C, and B additions in an effort to provide a basis to increase the upper-temperature oxidation limit. Oxidation exposures were conducted in air with 10% water vapor environments from 800-1000 C, with post oxidation characterization of the 900 C exposed samples by electron probe microanalysis (EPMA), scanning and transmission electron microscopy, and photo-stimulated luminescence spectroscopy (PSLS). Increased levels of Al, C, and B additions were found to increase the upper-temperature oxidation limit in air with water vapor to between 950 and 1000 C. These findings are discussed in terms of alloy microstructure and possible gettering of hydrogen from water vapor at second phase carbide and boride precipitates.

  20. Acute Upper Thermal Limits of Three Aquatic Invasive Invertebrates: Hot Water Treatment to Prevent Upstream Transport of Invasive Species

    NASA Astrophysics Data System (ADS)

    Beyer, Jessica; Moy, Philip; de Stasio, Bart

    2011-01-01

    Transport of aquatic invasive species (AIS) by boats traveling up rivers and streams is an important mechanism of secondary spread of AIS into watersheds. Because physical barriers to AIS movement also prevent navigation, alternate methods for preventing spread are necessary while allowing upstream navigation. One promising approach is to lift boats over physical barriers and then use hot water immersion to kill AIS attached to the hull, motor, or fishing gear. However, few data have been published on the acute upper thermal tolerance limits of potential invaders treated in this manner. To test the potential effectiveness of this approach for a planned boat lift on the Fox River of northeastern WI, USA, acute upper thermal limits were determined for three AIS, adult zebra mussels ( Dreissena polymorpha), quagga mussels ( Dreissena rostriformis bugensis), and spiny water fleas ( Bythotrephes longimanus) from the local area employing temperatures from 32 to 54°C and immersion times from 1 to 20 min. Mortality was determined after immersion followed by a 20-min recovery period. Immersion at 43°C for at least 5 min was required to ensure 100% mortality for all three species, but due to variability in the response by Bythotrephes a 10 min immersion would be more reliable. Overall there were no significant differences between the three species in acute upper thermal limits. Heated water can be an efficient, environmentally sound, and cost effective method of controlling AIS potentially transferred by boats, and our results should have both specific and wide-ranging applications in the prevention of the spread of aquatic invasive species.

  1. Upper limits for the rate constant for the reaction Br + H2O2 yields HB2 + HO2

    NASA Technical Reports Server (NTRS)

    Leu, M.-T.

    1980-01-01

    Upper limits for the rate constant for the reaction Br + H2O2 yields HBr + HO2 have been measured over the temperature range 298 to 417 K in a discharge flow system using a mass spectrometer as a detector. Results are k sub 1 less than 1.5 x 10 to the -15th power cu cm/s at 298 K and k sub 1 less than 3.0 x 10 to the -15th power cu cm/s at 417 K, respectively. The implication to stratospheric chemistry is discussed.

  2. Upper Limits on the Number of Small Bodies in Sedna-Like Orbits by the TAOS Project

    SciTech Connect

    Wang, J; Lehner, M J; Zhang, Z; Bianco, F B; Alcock, C; Chen, W; Axelrod, T; Byun, Y; Coehlo, N K; Cook, K H; Dave, R; de Pater, L; Porrata, R; Kim, D; King, S; Lee, T; Lin, H; Lissauer, J J; Marshall, S L; Protopapas, P; Rice, J A; Schwamb, M E; Wang, S; Wen, C

    2009-11-13

    We present the results of a search for occultation events by objects at distances between 100 and 1000 AU in lightcurves from the Taiwanese-American Occultation Survey (TAOS). We searched for consecutive, shallow flux reductions in the stellar lightcurves obtained by our survey between 7 February 2005 and 31 December 2006 with a total of {approx} 4.5 x 10{sup 9} three-telescope simultaneous photometric measurements. No events were detected, allowing us to set upper limits on the number density as a function of size and distance of objects in Sedna-like orbits, using simple models.

  3. Upper limits to pulsed gamma ray emission from PSR 0833-45, 1747-46, and 1818-04

    NASA Technical Reports Server (NTRS)

    Cherry, M. L.; Dunphy, P. P.; Chupp, E. L.; Forrest, D. J.; Ryan, J. M.

    1982-01-01

    Pulsed gamma ray emission from three pulsars (PSR 0833-45, 1747-46, and 1818-04) have been sought on a balloon flight of the University of New Hampshire Large Gamma Ray Telescope, which incorporates a shielded sodium iodide scintillator array, and was launched from Alice Springs, Australia. Over the energy range 0.1 - 10 MeV, no evidence is found for pulsed gamma rays, and upper limits are set for Vela which are comparable to, or below, the extrapolation to lower energies of the pulsed emission reported by SAS-2 and COS-B.

  4. The Extended GMRT Radio Halo Survey. I. New upper limits on radio halos and mini-halos

    NASA Astrophysics Data System (ADS)

    Kale, R.; Venturi, T.; Giacintucci, S.; Dallacasa, D.; Cassano, R.; Brunetti, G.; Macario, G.; Athreya, R.

    2013-09-01

    Context. A fraction of galaxy clusters host diffuse radio sources called radio halos, radio relics and mini-halos. These are associated with the relativistic electrons and magnetic fields present on ~Mpc scales in the intra-cluster medium. Aims: We aim to carry out a systematic radio survey of all luminous galaxy clusters selected from the REFLEX and eBCS X-ray catalogues with the Giant Metrewave Radio Telescope, to understand the statistical properties of the diffuse radio emission in galaxy clusters. Methods: We present the sample and first results from the Extended GMRT Radio Halo Survey (EGRHS), which is an extension of the GMRT Radio Halo Survey (GRHS, Venturi et al. 2007, 2008). Analysis of radio data at 610/ 235/ 325 MHz on 12 galaxy clusters are presented. Results: We report the detection of a newly discovered mini-halo in the cluster RX J1532.9+3021 at 610 MHz. The presence of a small-scale relic (~200 kpc) is suspected in the cluster Z348. We do not detect cluster-scale diffuse emission in 11 clusters. Robust upper limits on the detection of radio halo of size of 1 Mpc are determined. We also present upper limits on the detections of mini-halos in a sub-sample of cool-core clusters. The upper limits for radio halos and mini-halos are plotted in the radio power- X-ray luminosity plane and the correlations are discussed. Diffuse extended emission that is not related to the target clusters, but detected as by-products in the sensitive images of two of the cluster fields (A689 and RX J0439.0+0715) is also reported. Conclusions: Based on the information about the presence of radio halos (or upper limits), available on 48 clusters out of the total sample of 67 clusters (EGRHS+GRHS), we find that 23 ± 7% of the clusters host radio halos. The radio halo fraction rises to 31 ± 11%, when only the clusters with X-ray luminosities >8 × 1044 erg s-1 are considered. Mini-halos are found in ~50% of cool-core clusters. A qualitative examination of the X-ray images of

  5. A low upper limit on the subsurface rise speed of solar active regions

    PubMed Central

    Birch, Aaron C.; Schunker, Hannah; Braun, Douglas C.; Cameron, Robert; Gizon, Laurent; Löptien, Björn; Rempel, Matthias

    2016-01-01

    Magnetic field emerges at the surface of the Sun as sunspots and active regions. This process generates a poloidal magnetic field from a rising toroidal flux tube; it is a crucial but poorly understood aspect of the solar dynamo. The emergence of magnetic field is also important because it is a key driver of solar activity. We show that measurements of horizontal flows at the solar surface around emerging active regions, in combination with numerical simulations of solar magnetoconvection, can constrain the subsurface rise speed of emerging magnetic flux. The observed flows imply that the rise speed of the magnetic field is no larger than 150 m/s at a depth of 20 Mm, that is, well below the prediction of the (standard) thin flux tube model but in the range expected for convective velocities at this depth. We conclude that convective flows control the dynamics of rising flux tubes in the upper layers of the Sun and cannot be neglected in models of flux emergence. PMID:27453947

  6. A low upper limit on the subsurface rise speed of solar active regions.

    PubMed

    Birch, Aaron C; Schunker, Hannah; Braun, Douglas C; Cameron, Robert; Gizon, Laurent; Löptien, Björn; Rempel, Matthias

    2016-07-01

    Magnetic field emerges at the surface of the Sun as sunspots and active regions. This process generates a poloidal magnetic field from a rising toroidal flux tube; it is a crucial but poorly understood aspect of the solar dynamo. The emergence of magnetic field is also important because it is a key driver of solar activity. We show that measurements of horizontal flows at the solar surface around emerging active regions, in combination with numerical simulations of solar magnetoconvection, can constrain the subsurface rise speed of emerging magnetic flux. The observed flows imply that the rise speed of the magnetic field is no larger than 150 m/s at a depth of 20 Mm, that is, well below the prediction of the (standard) thin flux tube model but in the range expected for convective velocities at this depth. We conclude that convective flows control the dynamics of rising flux tubes in the upper layers of the Sun and cannot be neglected in models of flux emergence. PMID:27453947

  7. Further improvement of the upper limit on the direct 3α decay from the Hoyle state in 12C.

    PubMed

    Itoh, M; Ando, S; Aoki, T; Arikawa, H; Ezure, S; Harada, K; Hayamizu, T; Inoue, T; Ishikawa, T; Kato, K; Kawamura, H; Sakemi, Y; Uchiyama, A

    2014-09-01

    The direct 3α decay branch from the 02+ state at Ex=7.65  MeV in 12C, which is known as the Hoyle state, is considered to affect the triple-α reaction rate strongly and to give crucial information on its structure. We have performed a high-precision measurement of the 3α decay from this state using the 12C(12C,3α)12C reaction at E12C=110  MeV. The branching ratio of the direct 3α decay was under the detection limit in the present experiment. By comparing with Monte Carlo simulations for three decay mechanisms as the sequential decay through the ground state of ^{8}Be, the direct decay with equal energies of three α particles, and the direct decay to the phase space uniformly, we have obtained the upper limit of 0.2% on the direct 3α decay.

  8. Upper Limits on a Stochastic Gravitational-Wave Background Using LIGO and Virgo Interferometers at 600-1000 Hz

    NASA Technical Reports Server (NTRS)

    Abadie, J.; Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M.; Accadia, T.; Acernese, F.; Adams, C.; Adhikari, R.; Affeldt, C.; Agathos, M.; Agatsuma, K.; Ajith, P.; Allen, B.; Amador Ceron, E.; Amariutei, D.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Arain, M. A.; Araya, M. C.; Aston, S. M.; Blackburn, L.; Cannizzo, J.

    2012-01-01

    A stochastic background of gravitational waves is expected to arise from a superposition of many incoherent sources of gravitational waves, of either cosmological or astrophysical origin. This background is a target for the current generation of ground-based detectors. In this article we present the first joint search for a stochastic background using data from the LIGO and Virgo interferometers. In a frequency band of 600-1000 Hz, we obtained a 95% upper limit on the amplitude of omega(sub GW)(f) = omega(sub 3) (f/900Hz)3, of omega(sub 3) < 0.33, assuming a value of the Hubble parameter of h(sub 100) = 0.72. These new limits are a factor of seven better than the previous best in this frequency band.

  9. Upper limits to surface-force disturbances on LISA proof masses and the possibility of observing galactic binaries

    SciTech Connect

    Carbone, Ludovico; Ciani, Giacomo; Dolesi, Rita; Hueller, Mauro; Tombolato, David; Vitale, Stefano; Weber, William Joseph; Cavalleri, Antonella

    2007-02-15

    We have measured surface-force noise on a hollow replica of a LISA proof mass surrounded by its capacitive motion sensor. Forces are detected through the torque exerted on the proof mass by means of a torsion pendulum in the 0.1-30 mHz range. The sensor and electronics have the same design as for the flight hardware, including 4 mm gaps around the proof mass. The measured upper limit for forces would allow detection of a number of galactic binaries signals with signal-to-noise ratio up to {approx_equal}40 for 1 yr integration. We also discuss how LISA Pathfinder will substantially improve this limit, approaching the LISA performance.

  10. Upper limits to the number of Oort Cloud objects based on serendipitous occultation events search in X-rays

    NASA Astrophysics Data System (ADS)

    Chang, Hsiang-Kuang; Liu, Chih-Yuan; Shang, Jie-Rou

    2016-10-01

    Using all the RXTE archival data of Sco X-1 and GX 5-1, which amount to about 1.6 Ms in total, we searched for possible occultation events caused by Oort Cloud objects. The detection efficiency of our searching approach was studied with simulation. Our search is sensitive to object size of about 300 m in the inner Oort Cloud, taking 4000 au as a representative distance, and of 900 m in the outer Oort Cloud, taking 36 000 au as the representative distance. No occultation events were found in the 1.6 Ms data. We derived upper limits to the number of Oort Cloud objects, which are about three orders of magnitude higher than the highest theoretical estimates in the literature for the inner Oort Cloud, and about six orders higher for the outer Oort Cloud. Although these upper limits are not constraining enough, they are the first obtained observationally, without making any model assumptions about comet injection. They also provide guidance to such serendipitous occultation event search in the future.

  11. DETERMINATION OF AN UPPER LIMIT FOR THE WATER OUTGASSING RATE OF MAIN-BELT COMET P/2012 T1 (PANSTARRS)

    SciTech Connect

    O'Rourke, L.; Teyssier, D.; Kueppers, M.; Snodgrass, C.; De Val-Borro, M.; Hartogh, P.; Biver, N.; Bockelee-Morvan, D.; Hsieh, H.; Micheli, M.; Fernandez, Y.

    2013-09-01

    A new Main-Belt Comet (MBC) P/2012 T1 (PANSTARRS) was discovered on 2012 October 6, approximately one month after its perihelion, by the Pan-STARRS1 survey based in Hawaii. It displayed cometary activity upon its discovery with one hypothesis being that the activity was driven by sublimation of ices; as a result, we searched for emission assumed to be driven by the sublimation of subsurface ices. Our search was of the H{sub 2}O 1{sub 10}-1{sub 01} ground state rotational line at 557 GHz from P/2012 T1 (PANSTARRS) with the Heterodyne Instrument for the Far Infrared on board the Herschel Space Observatory on 2013 January 16, when the object was at a heliocentric distance of 2.504 AU and a geocentric distance of 2.064 AU. Perihelion was in early 2012 September at a distance of 2.411 AU. While no H{sub 2}O line emission was detected in our observations, we were able to derive sensitive 3{sigma} upper limits for the water production rate and column density of <7.63 Multiplication-Sign 10{sup 25} molecules s{sup -1} and of <1.61 Multiplication-Sign 10{sup 11} cm{sup -2}, respectively. An observation taken on 2013 January 15 using the Very Large Telescope found the MBC to be active during the Herschel observation, suggesting that any ongoing sublimation due to subsurface ice was lower than our upper limit.

  12. A Novel Power Efficient Location-Based Cooperative Routing with Transmission Power-Upper-Limit for Wireless Sensor Networks

    PubMed Central

    Shi, Juanfei; Calveras, Anna; Cheng, Ye; Liu, Kai

    2013-01-01

    The extensive usage of wireless sensor networks (WSNs) has led to the development of many power- and energy-efficient routing protocols. Cooperative routing in WSNs can improve performance in these types of networks. In this paper we discuss the existing proposals and we propose a routing algorithm for wireless sensor networks called Power Efficient Location-based Cooperative Routing with Transmission Power-upper-limit (PELCR-TP). The algorithm is based on the principle of minimum link power and aims to take advantage of nodes cooperation to make the link work well in WSNs with a low transmission power. In the proposed scheme, with a determined transmission power upper limit, nodes find the most appropriate next nodes and single-relay nodes with the proposed algorithm. Moreover, this proposal subtly avoids non-working nodes, because we add a Bad nodes Avoidance Strategy (BAS). Simulation results show that the proposed algorithm with BAS can significantly improve the performance in reducing the overall link power, enhancing the transmission success rate and decreasing the retransmission rate. PMID:23676625

  13. Improved Upper Limits on the Stochastic Gravitational-Wave Background from 2009-2010 LIGO and Virgo Data

    NASA Astrophysics Data System (ADS)

    Aasi, J.; Abbott, B. P.; Abbott, R.; Abbott, T.; Abernathy, M. R.; Accadia, T.; Acernese, F.; Ackley, K.; Adams, C.; Adams, T.; Addesso, P.; Adhikari, R. X.; Affeldt, C.; Agathos, M.; Aggarwal, N.; Aguiar, O. D.; Ain, A.; Ajith, P.; Alemic, A.; Allen, B.; Allocca, A.; Amariutei, D.; Andersen, M.; Anderson, R.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Araya, M. C.; Arceneaux, C.; Areeda, J.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Austin, L.; Aylott, B. E.; Babak, S.; Baker, P. T.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barbet, M.; Barish, B. C.; Barker, D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barton, M. A.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J. C.; Bauchrowitz, J.; Bauer, Th. S.; Behnke, B.; Bejger, M.; Beker, M. G.; Belczynski, C.; Bell, A. S.; Bell, C.; Bergmann, G.; Bersanetti, D.; Bertolini, A.; Betzwieser, J.; Beyersdorf, P. T.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Biscans, S.; Bitossi, M.; Bizouard, M. A.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Bloemen, S.; Blom, M.; Bock, O.; Bodiya, T. P.; Boer, M.; Bogaert, G.; Bogan, C.; Bond, C.; Bondu, F.; Bonelli, L.; Bonnand, R.; Bork, R.; Born, M.; Boschi, V.; Bose, Sukanta; Bosi, L.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Briant, T.; Bridges, D. O.; Brillet, A.; Brinkmann, M.; Brisson, V.; Brooks, A. F.; Brown, D. A.; Brown, D. D.; Brückner, F.; Buchman, S.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Burman, R.; Buskulic, D.; Buy, C.; Cadonati, L.; Cagnoli, G.; Bustillo, J. Calderón; Calloni, E.; Camp, J. B.; Campsie, P.; Cannon, K. C.; Canuel, B.; Cao, J.; Capano, C. D.; Carbognani, F.; Carbone, L.; Caride, S.; Castiglia, A.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Celerier, C.; Cella, G.; Cepeda, C.; Cesarini, E.; Chakraborty, R.; Chalermsongsak, T.; Chamberlin, S. J.; Chao, S.; Charlton, P.; Chassande-Mottin, E.; Chen, X.; Chen, Y.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Chow, J.; Christensen, N.; Chu, Q.; Chua, S. S. Y.; Chung, S.; Ciani, G.; Clara, F.; Clark, J. A.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colla, A.; Collette, C.; Colombini, M.; Cominsky, L.; Constancio, M.; Conte, A.; Cook, D.; Corbitt, T. R.; Cordier, M.; Cornish, N.; Corpuz, A.; Corsi, A.; Costa, C. A.; Coughlin, M. W.; Coughlin, S.; Coulon, J.-P.; Countryman, S.; Couvares, P.; Coward, D. M.; Cowart, M.; Coyne, D. C.; Coyne, R.; Craig, K.; Creighton, J. D. E.; Crowder, S. G.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dahl, K.; Canton, T. Dal; Damjanic, M.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Dattilo, V.; Daveloza, H.; Davier, M.; Davies, G. S.; Daw, E. J.; Day, R.; Dayanga, T.; Debreczeni, G.; Degallaix, J.; Deléglise, S.; Del Pozzo, W.; Denker, T.; Dent, T.; Dereli, H.; Dergachev, V.; De Rosa, R.; DeRosa, R. T.; DeSalvo, R.; Dhurandhar, S.; Díaz, M.; Di Fiore, L.; Di Lieto, A.; Di Palma, I.; Di Virgilio, A.; Donath, A.; Donovan, F.; Dooley, K. L.; Doravari, S.; Dossa, S.; Douglas, R.; Downes, T. P.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Dwyer, S.; Eberle, T.; Edo, T.; Edwards, M.; Effler, A.; Eggenstein, H.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Endrőczi, G.; Essick, R.; Etzel, T.; Evans, M.; Evans, T.; Factourovich, M.; Fafone, V.; Fairhurst, S.; Fang, Q.; Farinon, S.; Farr, B.; Farr, W. M.; Favata, M.; Fehrmann, H.; Fejer, M. M.; Feldbaum, D.; Feroz, F.; Ferrante, I.; Ferrini, F.; Fidecaro, F.; Finn, L. S.; Fiori, I.; Fisher, R. P.; Flaminio, R.; Fournier, J.-D.; Franco, S.; Frasca, S.; Frasconi, F.; Frede, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Fritschel, P.; Frolov, V. V.; Fulda, P.; Fyffe, M.; Gair, J.; Gammaitoni, L.; Gaonkar, S.; Garufi, F.; Gehrels, N.; Gemme, G.; Genin, E.; Gennai, A.; Ghosh, S.; Giaime, J. A.; Giardina, K. D.; Giazotto, A.; Gill, C.; Gleason, J.; Goetz, E.; Goetz, R.; Gondan, L.; González, G.; Gordon, N.; Gorodetsky, M. L.; Gossan, S.; Goßler, S.; Gouaty, R.; Gräf, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Groot, P.; Grote, H.; Grover, K.; Grunewald, S.; Guidi, G. M.; Guido, C.; Gushwa, K.; Gustafson, E. K.; Gustafson, R.; Hammer, D.; Hammond, G.; Hanke, M.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Hart, M.; Hartman, M. T.; Haster, C.-J.; Haughian, K.; Heidmann, A.; Heintze, M.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Heptonstall, A. W.; Heurs, M.; Hewitson, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Holt, K.; Hooper, S.; Hopkins, P.; Hosken, D. J.; Hough, J.; Howell, E. J.; Hu, Y.; Huerta, E.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh, M.; Huynh-Dinh, T.; Ingram, D. R.; Inta, R.; Isogai, T.; Ivanov, A.; Iyer, B. R.; Izumi, K.; Jacobson, M.; James, E.; Jang, H.; Jaranowski, P.; Ji, Y.; Jiménez-Forteza, F.; Johnson, W. W.; Jones, D. I.; Jones, R.; Jonker, R. J. G.; Ju, L.; Haris, K.; Kalmus, P.; Kalogera, V.; Kandhasamy, S.; Kang, G.; Kanner, J. B.; Karlen, J.; Kasprzack, M.; Katsavounidis, E.; Katzman, W.; Kaufer, H.; Kawabe, K.; Kawazoe, F.; Kéfélian, F.; Keiser, G. M.; Keitel, D.; Kelley, D. B.; Kells, W.; Khalaidovski, A.; Khalili, F. Y.; Khazanov, E. A.; Kim, C.; Kim, K.; Kim, N.; Kim, N. G.; Kim, Y.-M.; King, E. J.; King, P. J.; Kinzel, D. L.; Kissel, J. S.; Klimenko, S.; Kline, J.; Koehlenbeck, S.; Kokeyama, K.; Kondrashov, V.; Koranda, S.; Korth, W. Z.; Kowalska, I.; Kozak, D. B.; Kremin, A.; Kringel, V.; Królak, A.; Kuehn, G.; Kumar, A.; Kumar, P.; Kumar, R.; Kuo, L.; Kutynia, A.; Kwee, P.; Landry, M.; Lantz, B.; Larson, S.; Lasky, P. D.; Lawrie, C.; Lazzarini, A.; Lazzaro, C.; Leaci, P.; Leavey, S.; Lebigot, E. O.; Lee, C.-H.; Lee, H. K.; Lee, H. M.; Lee, J.; Leonardi, M.; Leong, J. R.; Le Roux, A.; Leroy, N.; Letendre, N.; Levin, Y.; Levine, B.; Lewis, J.; Li, T. G. F.; Libbrecht, K.; Libson, A.; Lin, A. C.; Littenberg, T. B.; Litvine, V.; Lockerbie, N. A.; Lockett, V.; Lodhia, D.; Loew, K.; Logue, J.; Lombardi, A. L.; Lorenzini, M.; Loriette, V.; Lormand, M.; Losurdo, G.; Lough, J.; Lubinski, M. J.; Lück, H.; Luijten, E.; Lundgren, A. P.; Lynch, R.; Ma, Y.; Macarthur, J.; Macdonald, E. P.; MacDonald, T.; Machenschalk, B.; MacInnis, M.; Macleod, D. M.; Magana-Sandoval, F.; Mageswaran, M.; Maglione, C.; Mailand, K.; Majorana, E.; Maksimovic, I.; Malvezzi, V.; Man, N.; Manca, G. M.; Mandel, I.; Mandic, V.; Mangano, V.; Mangini, N.; Mantovani, M.; Marchesoni, F.; Marion, F.; Márka, S.; Márka, Z.; Markosyan, A.; Maros, E.; Marque, J.; Martelli, F.; Martin, I. W.; Martin, R. M.; Martinelli, L.; Martynov, D.; Marx, J. N.; Mason, K.; Masserot, A.; Massinger, T. J.; Matichard, F.; Matone, L.; Matzner, R. A.; Mavalvala, N.; Mazumder, N.; Mazzolo, G.; McCarthy, R.; McClelland, D. E.; McGuire, S. C.; McIntyre, G.; McIver, J.; McLin, K.; Meacher, D.; Meadors, G. D.; Mehmet, M.; Meidam, J.; Meinders, M.; Melatos, A.; Mendell, G.; Mercer, R. A.; Meshkov, S.; Messenger, C.; Meyers, P.; Miao, H.; Michel, C.; Mikhailov, E. E.; Milano, L.; Milde, S.; Miller, J.; Minenkov, Y.; Mingarelli, C. M. F.; Mishra, C.; Mitra, S.; Mitrofanov, V. P.; Mitselmakher, G.; Mittleman, R.; Moe, B.; Moesta, P.; Mohan, M.; Mohapatra, S. R. P.; Moraru, D.; Moreno, G.; Morgado, N.; Morriss, S. R.; Mossavi, K.; Mours, B.; Mow-Lowry, C. M.; Mueller, C. L.; Mueller, G.; Mukherjee, S.; Mullavey, A.; Munch, J.; Murphy, D.; Murray, P. G.; Mytidis, A.; Nagy, M. F.; Kumar, D. Nanda; Nardecchia, I.; Naticchioni, L.; Nayak, R. K.; Necula, V.; Nelemans, G.; Neri, I.; Neri, M.; Newton, G.; Nguyen, T.; Nitz, A.; Nocera, F.; Nolting, D.; Normandin, M. E. N.; Nuttall, L. K.; Ochsner, E.; O'Dell, J.; Oelker, E.; Oh, J. J.; Oh, S. H.; Ohme, F.; Oppermann, P.; O'Reilly, B.; O'Shaughnessy, R.; Osthelder, C.; Ottaway, D. J.; Ottens, R. S.; Overmier, H.; Owen, B. J.; Padilla, C.; Pai, A.; Palashov, O.; Palomba, C.; Pan, H.; Pan, Y.; Pankow, C.; Paoletti, F.; Paoletti, R.; Paris, H.; Pasqualetti, A.; Passaquieti, R.; Passuello, D.; Pedraza, M.; Penn, S.; Perreca, A.; Phelps, M.; Pichot, M.; Pickenpack, M.; Piergiovanni, F.; Pierro, V.; Pinard, L.; Pinto, I. M.; Pitkin, M.; Poeld, J.; Poggiani, R.; Poteomkin, A.; Powell, J.; Prasad, J.; Premachandra, S.; Prestegard, T.; Price, L. R.; Prijatelj, M.; Privitera, S.; Prodi, G. A.; Prokhorov, L.; Puncken, O.; Punturo, M.; Puppo, P.; Qin, J.; Quetschke, V.; Quintero, E.; Quiroga, G.; Quitzow-James, R.; Raab, F. J.; Rabeling, D. S.; Rácz, I.; Radkins, H.; Raffai, P.; Raja, S.; Rajalakshmi, G.; Rakhmanov, M.; Ramet, C.; Ramirez, K.; Rapagnani, P.; Raymond, V.; Re, V.; Read, J.; Reed, C. M.; Regimbau, T.; Reid, S.; Reitze, D. H.; Rhoades, E.; Ricci, F.; Riles, K.; Robertson, N. A.; Robinet, F.; Rocchi, A.; Rodruck, M.; Rolland, L.; Rollins, J. G.; Romano, J. D.; Romano, R.; Romanov, G.; Romie, J. H.; Rosińska, D.; Rowan, S.; Rüdiger, A.; Ruggi, P.; Ryan, K.; Salemi, F.; Sammut, L.; Sandberg, V.; Sanders, J. R.; Sannibale, V.; Santiago-Prieto, I.; Saracco, E.; Sassolas, B.; Sathyaprakash, B. S.; Saulson, P. R.; Savage, R.; Scheuer, J.; Schilling, R.; Schnabel, R.; Schofield, R. M. S.; Schreiber, E.; Schuette, D.; Schutz, B. F.; Scott, J.; Scott, S. M.; Sellers, D.; Sengupta, A. S.; Sentenac, D.; Sequino, V.; Sergeev, A.; Shaddock, D.; Shah, S.; Shahriar, M. S.; Shaltev, M.; Shapiro, B.; Shawhan, P.; Shoemaker, D. H.; Sidery, T. L.; Siellez, K.; Siemens, X.; Sigg, D.; Simakov, D.; Singer, A.; Singer, L.; Singh, R.; Sintes, A. M.; Slagmolen, B. J. J.; Slutsky, J.; Smith, J. R.; Smith, M.; Smith, R. J. E.; Smith-Lefebvre, N. D.; Son, E. J.; Sorazu, B.; Souradeep, T.; Sperandio, L.; Staley, A.; Stebbins, J.; Steinlechner, J.; Steinlechner, S.; Stephens, B. C.; Steplewski, S.; Stevenson, S.; Stone, R.; Stops, D.; Strain, K. A.; Straniero, N.; Strigin, S.; Sturani, R.; Stuver, A. L.; Summerscales, T. Z.; Susmithan, S.; Sutton, P. J.; Swinkels, B.; Tacca, M.; Talukder, D.; Tanner, D. B.; Tarabrin, S. P.; Taylor, R.; ter Braack, A. P. M.; Thirugnanasambandam, M. P.; Thomas, M.; Thomas, P.; Thorne, K. A.; Thorne, K. S.; Thrane, E.; Tiwari, V.; Tokmakov, K. V.; Tomlinson, C.; Toncelli, A.; Tonelli, M.; Torre, O.; Torres, C. V.; Torrie, C. I.; Travasso, F.; Traylor, G.; Tse, M.; Ugolini, D.; Unnikrishnan, C. S.; Urban, A. L.; Urbanek, K.; Vahlbruch, H.; Vajente, G.; Valdes, G.; Vallisneri, M.; van den Brand, J. F. J.; Van Den Broeck, C.; van der Putten, S.; van der Sluys, M. V.; van Heijningen, J.; van Veggel, A. A.; Vass, S.; Vasúth, M.; Vaulin, R.; Vecchio, A.; Vedovato, G.; Veitch, J.; Veitch, P. J.; Venkateswara, K.; Verkindt, D.; Verma, S. S.; Vetrano, F.; Viceré, A.; Vincent-Finley, R.; Vinet, J.-Y.; Vitale, S.; Vo, T.; Vocca, H.; Vorvick, C.; Vousden, W. D.; Vyachanin, S. P.; Wade, A.; Wade, L.; Wade, M.; Walker, M.; Wallace, L.; Wang, M.; Wang, X.; Ward, R. L.; Was, M.; Weaver, B.; Wei, L.-W.; Weinert, M.; Weinstein, A. J.; Weiss, R.; Welborn, T.; Wen, L.; Wessels, P.; West, M.; Westphal, T.; Wette, K.; Whelan, J. T.; White, D. J.; Whiting, B. F.; Wiesner, K.; Wilkinson, C.; Williams, K.; Williams, L.; Williams, R.; Williams, T.; Williamson, A. R.; Willis, J. L.; Willke, B.; Wimmer, M.; Winkler, W.; Wipf, C. C.; Wiseman, A. G.; Wittel, H.; Woan, G.; Worden, J.; Yablon, J.; Yakushin, I.; Yamamoto, H.; Yancey, C. C.; Yang, H.; Yang, Z.; Yoshida, S.; Yvert, M.; ZadroŻny, A.; Zanolin, M.; Zendri, J.-P.; Zhang, Fan; Zhang, L.; Zhao, C.; Zhu, X. J.; Zucker, M. E.; Zuraw, S.; Zweizig, J.; LIGO; Virgo Collaboration

    2014-12-01

    Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is unavailable through standard electromagnetic observations, making its study of fundamental importance to understanding the evolution of the Universe. We carry out a search for the stochastic background with the latest data from the LIGO and Virgo detectors. Consistent with predictions from most stochastic gravitational-wave background models, the data display no evidence of a stochastic gravitational-wave signal. Assuming a gravitational-wave spectrum of ΩGW(f )=Ωα(f/fref ) α , we place 95% confidence level upper limits on the energy density of the background in each of four frequency bands spanning 41.5-1726 Hz. In the frequency band of 41.5-169.25 Hz for a spectral index of α =0 , we constrain the energy density of the stochastic background to be ΩGW(f )<5.6 ×1 0-6 . For the 600-1000 Hz band, ΩGW(f )<0.14 (f /900 Hz )3 , a factor of 2.5 lower than the best previously reported upper limits. We find ΩGW(f )<1.8 ×1 0-4 using a spectral index of zero for 170-600 Hz and ΩGW(f )<1.0 (f /1300 Hz )3 for 1000-1726 Hz, bands in which no previous direct limits have been placed. The limits in these four bands are the lowest direct measurements to date on the stochastic background. We discuss the implications of these results in light of the recent claim by the BICEP2 experiment of the possible evidence for inflationary gravitational waves.

  14. Improved upper limits on the stochastic gravitational-wave background from 2009-2010 LIGO and Virgo data.

    PubMed

    Aasi, J; Abbott, B P; Abbott, R; Abbott, T; Abernathy, M R; Accadia, T; Acernese, F; Ackley, K; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Affeldt, C; Agathos, M; Aggarwal, N; Aguiar, O D; Ain, A; Ajith, P; Alemic, A; Allen, B; Allocca, A; Amariutei, D; Andersen, M; Anderson, R; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C; Areeda, J; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Austin, L; Aylott, B E; Babak, S; Baker, P T; Ballardin, G; Ballmer, S W; Barayoga, J C; Barbet, M; Barish, B C; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Basti, A; Batch, J C; Bauchrowitz, J; Bauer, Th S; Behnke, B; Bejger, M; Beker, M G; Belczynski, C; Bell, A S; Bell, C; Bergmann, G; Bersanetti, D; Bertolini, A; Betzwieser, J; Beyersdorf, P T; Bilenko, I A; Billingsley, G; Birch, J; Biscans, S; Bitossi, M; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Bloemen, S; Blom, M; Bock, O; Bodiya, T P; Boer, M; Bogaert, G; Bogan, C; Bond, C; Bondu, F; Bonelli, L; Bonnand, R; Bork, R; Born, M; Boschi, V; Bose, Sukanta; Bosi, L; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Briant, T; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Brooks, A F; Brown, D A; Brown, D D; Brückner, F; Buchman, S; Bulik, T; Bulten, H J; Buonanno, A; Burman, R; Buskulic, D; Buy, C; Cadonati, L; Cagnoli, G; Bustillo, J Calderón; Calloni, E; Camp, J B; Campsie, P; Cannon, K C; Canuel, B; Cao, J; Capano, C D; Carbognani, F; Carbone, L; Caride, S; Castiglia, A; Caudill, S; Cavaglià, M; Cavalier, F; Cavalieri, R; Celerier, C; Cella, G; Cepeda, C; Cesarini, E; Chakraborty, R; Chalermsongsak, T; Chamberlin, S J; Chao, S; Charlton, P; Chassande-Mottin, E; Chen, X; Chen, Y; Chincarini, A; Chiummo, A; Cho, H S; Chow, J; Christensen, N; Chu, Q; Chua, S S Y; Chung, S; Ciani, G; Clara, F; Clark, J A; Cleva, F; Coccia, E; Cohadon, P-F; Colla, A; Collette, C; Colombini, M; Cominsky, L; Constancio, M; Conte, A; Cook, D; Corbitt, T R; Cordier, M; Cornish, N; Corpuz, A; Corsi, A; Costa, C A; Coughlin, M W; Coughlin, S; Coulon, J-P; Countryman, S; Couvares, P; Coward, D M; Cowart, M; Coyne, D C; Coyne, R; Craig, K; Creighton, J D E; Crowder, S G; Cumming, A; Cunningham, L; Cuoco, E; Dahl, K; Canton, T Dal; Damjanic, M; Danilishin, S L; D'Antonio, S; Danzmann, K; Dattilo, V; Daveloza, H; Davier, M; Davies, G S; Daw, E J; Day, R; Dayanga, T; Debreczeni, G; Degallaix, J; Deléglise, S; Del Pozzo, W; Denker, T; Dent, T; Dereli, H; Dergachev, V; De Rosa, R; DeRosa, R T; DeSalvo, R; Dhurandhar, S; Díaz, M; Di Fiore, L; Di Lieto, A; Di Palma, I; Di Virgilio, A; Donath, A; Donovan, F; Dooley, K L; Doravari, S; Dossa, S; Douglas, R; Downes, T P; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Dwyer, S; Eberle, T; Edo, T; Edwards, M; Effler, A; Eggenstein, H; Ehrens, P; Eichholz, J; Eikenberry, S S; Endrőczi, G; Essick, R; Etzel, T; Evans, M; Evans, T; Factourovich, M; Fafone, V; Fairhurst, S; Fang, Q; Farinon, S; Farr, B; Farr, W M; Favata, M; Fehrmann, H; Fejer, M M; Feldbaum, D; Feroz, F; Ferrante, I; Ferrini, F; Fidecaro, F; Finn, L S; Fiori, I; Fisher, R P; Flaminio, R; Fournier, J-D; Franco, S; Frasca, S; Frasconi, F; Frede, M; Frei, Z; Freise, A; Frey, R; Fricke, T T; Fritschel, P; Frolov, V V; Fulda, P; Fyffe, M; Gair, J; Gammaitoni, L; Gaonkar, S; Garufi, F; Gehrels, N; Gemme, G; Genin, E; Gennai, A; Ghosh, S; Giaime, J A; Giardina, K D; Giazotto, A; Gill, C; Gleason, J; Goetz, E; Goetz, R; Gondan, L; González, G; Gordon, N; Gorodetsky, M L; Gossan, S; Gossler, S; Gouaty, R; Gräf, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greenhalgh, R J S; Gretarsson, A M; Groot, P; Grote, H; Grover, K; Grunewald, S; Guidi, G M; Guido, C; Gushwa, K; Gustafson, E K; Gustafson, R; Hammer, D; Hammond, G; Hanke, M; Hanks, J; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Hart, M; Hartman, M T; Haster, C-J; Haughian, K; Heidmann, A; Heintze, M; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Heptonstall, A W; Heurs, M; Hewitson, M; Hild, S; Hoak, D; Hodge, K A; Holt, K; Hooper, S; Hopkins, P; Hosken, D J; Hough, J; Howell, E J; Hu, Y; Huerta, E; Hughey, B; Husa, S; Huttner, S H; Huynh, M; Huynh-Dinh, T; Ingram, D R; Inta, R; Isogai, T; Ivanov, A; Iyer, B R; Izumi, K; Jacobson, M; James, E; Jang, H; Jaranowski, P; Ji, Y; Jiménez-Forteza, F; Johnson, W W; Jones, D I; Jones, R; Jonker, R J G; Ju, L; K, Haris; Kalmus, P; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Karlen, J; Kasprzack, M; Katsavounidis, E; Katzman, W; Kaufer, H; Kawabe, K; Kawazoe, F; Kéfélian, F; Keiser, G M; Keitel, D; Kelley, D B; Kells, W; Khalaidovski, A; Khalili, F Y; Khazanov, E A; Kim, C; Kim, K; Kim, N; Kim, N G; Kim, Y-M; King, E J; King, P J; Kinzel, D L; Kissel, J S; Klimenko, S; Kline, J; Koehlenbeck, S; Kokeyama, K; Kondrashov, V; Koranda, S; Korth, W Z; Kowalska, I; Kozak, D B; Kremin, A; Kringel, V; Królak, A; Kuehn, G; Kumar, A; Kumar, P; Kumar, R; Kuo, L; Kutynia, A; Kwee, P; Landry, M; Lantz, B; Larson, S; Lasky, P D; Lawrie, C; Lazzarini, A; Lazzaro, C; Leaci, P; Leavey, S; Lebigot, E O; Lee, C-H; Lee, H K; Lee, H M; Lee, J; Leonardi, M; Leong, J R; Le Roux, A; Leroy, N; Letendre, N; Levin, Y; Levine, B; Lewis, J; Li, T G F; Libbrecht, K; Libson, A; Lin, A C; Littenberg, T B; Litvine, V; Lockerbie, N A; Lockett, V; Lodhia, D; Loew, K; Logue, J; Lombardi, A L; Lorenzini, M; Loriette, V; Lormand, M; Losurdo, G; Lough, J; Lubinski, M J; Lück, H; Luijten, E; Lundgren, A P; Lynch, R; Ma, Y; Macarthur, J; Macdonald, E P; MacDonald, T; Machenschalk, B; MacInnis, M; Macleod, D M; Magana-Sandoval, F; Mageswaran, M; Maglione, C; Mailand, K; Majorana, E; Maksimovic, I; Malvezzi, V; Man, N; Manca, G M; Mandel, I; Mandic, V; Mangano, V; Mangini, N; Mantovani, M; Marchesoni, F; Marion, F; Márka, S; Márka, Z; Markosyan, A; Maros, E; Marque, J; Martelli, F; Martin, I W; Martin, R M; Martinelli, L; Martynov, D; Marx, J N; Mason, K; Masserot, A; Massinger, T J; Matichard, F; 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    2014-12-01

    Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is unavailable through standard electromagnetic observations, making its study of fundamental importance to understanding the evolution of the Universe. We carry out a search for the stochastic background with the latest data from the LIGO and Virgo detectors. Consistent with predictions from most stochastic gravitational-wave background models, the data display no evidence of a stochastic gravitational-wave signal. Assuming a gravitational-wave spectrum of Ω_{GW}(f)=Ω_{α}(f/f_{ref})^{α}, we place 95% confidence level upper limits on the energy density of the background in each of four frequency bands spanning 41.5-1726 Hz. In the frequency band of 41.5-169.25 Hz for a spectral index of α=0, we constrain the energy density of the stochastic background to be Ω_{GW}(f)<5.6×10^{-6}. For the 600-1000 Hz band, Ω_{GW}(f)<0.14(f/900  Hz)^{3}, a factor of 2.5 lower than the best previously reported upper limits. We find Ω_{GW}(f)<1.8×10^{-4} using a spectral index of zero for 170-600 Hz and Ω_{GW}(f)<1.0(f/1300  Hz)^{3} for 1000-1726 Hz, bands in which no previous direct limits have been placed. The limits in these four bands are the lowest direct measurements to date on the stochastic background. We discuss the implications of these results in light of the recent claim by the BICEP2 experiment of the possible evidence for inflationary gravitational waves. PMID:25526109

  15. Moisture status during a strong El Niño explains a tropical montane cloud forest's upper limit.

    PubMed

    Crausbay, Shelley D; Frazier, Abby G; Giambelluca, Thomas W; Longman, Ryan J; Hotchkiss, Sara C

    2014-05-01

    Growing evidence suggests short-duration climate events may drive community structure and composition more directly than long-term climate means, particularly at ecotones where taxa are close to their physiological limits. Here we use an empirical habitat model to evaluate the role of microclimate during a strong El Niño in structuring a tropical montane cloud forest's upper limit and composition in Hawai'i. We interpolate climate surfaces, derived from a high-density network of climate stations, to permanent vegetation plots. Climatic predictor variables include (1) total rainfall, (2) mean relative humidity, and (3) mean temperature representing non-El Niño periods and a strong El Niño drought. Habitat models explained species composition within the cloud forest with non-El Niño rainfall; however, the ecotone at the cloud forest's upper limit was modeled with relative humidity during a strong El Niño drought and secondarily with non-El Niño rainfall. This forest ecotone may be particularly responsive to strong, short-duration climate variability because taxa here, particularly the isohydric dominant Metrosideros polymorpha, are near their physiological limits. Overall, this study demonstrates moisture's overarching influence on a tropical montane ecosystem, and suggests that short-term climate events affecting moisture status are particularly relevant at tropical ecotones. This study further suggests that predicting the consequences of climate change here, and perhaps in other tropical montane settings, will rely on the skill and certainty around future climate models of regional rainfall, relative humidity, and El Niño.

  16. Improved upper limits on the stochastic gravitational-wave background from 2009-2010 LIGO and Virgo data.

    PubMed

    Aasi, J; Abbott, B P; Abbott, R; Abbott, T; Abernathy, M R; Accadia, T; Acernese, F; Ackley, K; Adams, C; Adams, T; Addesso, P; Adhikari, R X; Affeldt, C; Agathos, M; Aggarwal, N; Aguiar, O D; Ain, A; Ajith, P; Alemic, A; Allen, B; Allocca, A; Amariutei, D; Andersen, M; Anderson, R; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C; Areeda, J; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Austin, L; Aylott, B E; Babak, S; Baker, P T; Ballardin, G; Ballmer, S W; Barayoga, J C; Barbet, M; Barish, B C; Barker, D; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Basti, A; Batch, J C; Bauchrowitz, J; Bauer, Th S; Behnke, B; Bejger, M; Beker, M G; Belczynski, C; Bell, A S; Bell, C; Bergmann, G; Bersanetti, D; Bertolini, A; Betzwieser, J; Beyersdorf, P T; Bilenko, I A; Billingsley, G; Birch, J; Biscans, S; Bitossi, M; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Bloemen, S; Blom, M; Bock, O; Bodiya, T P; Boer, M; Bogaert, G; Bogan, C; Bond, C; Bondu, F; Bonelli, L; Bonnand, R; Bork, R; Born, M; Boschi, V; Bose, Sukanta; Bosi, L; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Briant, T; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Brooks, A F; Brown, D A; Brown, D D; Brückner, F; Buchman, S; Bulik, T; Bulten, H J; Buonanno, A; Burman, R; Buskulic, D; Buy, C; Cadonati, L; Cagnoli, G; Bustillo, J Calderón; Calloni, E; Camp, J B; Campsie, P; Cannon, K C; Canuel, B; Cao, J; Capano, C D; Carbognani, F; Carbone, L; Caride, S; Castiglia, A; Caudill, S; Cavaglià, M; Cavalier, F; Cavalieri, R; Celerier, C; Cella, G; Cepeda, C; Cesarini, E; Chakraborty, R; Chalermsongsak, T; Chamberlin, S J; Chao, S; Charlton, P; Chassande-Mottin, E; Chen, X; Chen, Y; Chincarini, A; Chiummo, A; Cho, H S; Chow, J; Christensen, N; Chu, Q; Chua, S S Y; Chung, S; Ciani, G; Clara, F; Clark, J A; Cleva, F; Coccia, E; Cohadon, P-F; Colla, A; Collette, C; Colombini, M; Cominsky, L; Constancio, M; Conte, A; Cook, D; 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Willis, J L; Willke, B; Wimmer, M; Winkler, W; Wipf, C C; Wiseman, A G; Wittel, H; Woan, G; Worden, J; Yablon, J; Yakushin, I; Yamamoto, H; Yancey, C C; Yang, H; Yang, Z; Yoshida, S; Yvert, M; Zadrożny, A; Zanolin, M; Zendri, J-P; Zhang, Fan; Zhang, L; Zhao, C; Zhu, X J; Zucker, M E; Zuraw, S; Zweizig, J

    2014-12-01

    Gravitational waves from a variety of sources are predicted to superpose to create a stochastic background. This background is expected to contain unique information from throughout the history of the Universe that is unavailable through standard electromagnetic observations, making its study of fundamental importance to understanding the evolution of the Universe. We carry out a search for the stochastic background with the latest data from the LIGO and Virgo detectors. Consistent with predictions from most stochastic gravitational-wave background models, the data display no evidence of a stochastic gravitational-wave signal. Assuming a gravitational-wave spectrum of Ω_{GW}(f)=Ω_{α}(f/f_{ref})^{α}, we place 95% confidence level upper limits on the energy density of the background in each of four frequency bands spanning 41.5-1726 Hz. In the frequency band of 41.5-169.25 Hz for a spectral index of α=0, we constrain the energy density of the stochastic background to be Ω_{GW}(f)<5.6×10^{-6}. For the 600-1000 Hz band, Ω_{GW}(f)<0.14(f/900  Hz)^{3}, a factor of 2.5 lower than the best previously reported upper limits. We find Ω_{GW}(f)<1.8×10^{-4} using a spectral index of zero for 170-600 Hz and Ω_{GW}(f)<1.0(f/1300  Hz)^{3} for 1000-1726 Hz, bands in which no previous direct limits have been placed. The limits in these four bands are the lowest direct measurements to date on the stochastic background. We discuss the implications of these results in light of the recent claim by the BICEP2 experiment of the possible evidence for inflationary gravitational waves.

  17. Evidence for a fundamental stellar upper mass limit from clustered star formation, and some implications therof

    NASA Astrophysics Data System (ADS)

    Kroupa, Pavel; Weidner, Carsten

    Theoretical considerations lead to the expectation that stars should not have masses larger than about m_{max*}=60-120M_⊙, while the observational evidence has been ambiguous. Only very recently has a physical stellar mass limit near 150M_⊙ emerged thanks to modern high-resolution observations of local star-burst clusters. But this limit does not appear to depend on metallicity, in contradiction to theory. Important uncertainties remain though. It is now also emerging that star-clusters limit the masses of their constituent stars, such that a well-defined relation between the mass of the most massive star in a cluster and the cluster mass, m_{max}=F(M_{ecl}) ≤ m_{max*}≈ 150M_⊙, exists. One rather startling finding is that the observational data strongly favour clusters being built-up by consecutively forming more-massive stars until the most massive stars terminate further star-formation. The relation also implies that composite populations, which consist of many star clusters, most of which may be dissolved, must have steeper composite IMFs than simple stellar populations such as are found in individual clusters. Thus, for example, 10^5 Taurus-Auriga star-forming groups, each with 20 stars, will ever only sample the IMF below about 1M_⊙. This IMF will therefore not be identical to the IMF of one cluster with 2×, 10^6 stars. The implication is that the star-formation history of a galaxy critically determines its integrated galaxial IMF and thus the total number of supernovae per star and its chemical enrichment history. Galaxy formation and evolution models that rely on an invariant IMF would be wrong.

  18. An upper limit on the stochastic gravitational-wave background of cosmological origin.

    PubMed

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Tarabrin, S P; Taylor, J R; Taylor, R; Terenzi, R; Thacker, J; Thorne, K A; Thorne, K S; Thüring, A; Tokmakov, K V; Toncelli, A; Tonelli, M; Torres, C; Torrie, C; Tournefier, E; Travasso, F; Traylor, G; Trias, M; Trummer, J; Ugolini, D; Ulmen, J; Urbanek, K; Vahlbruch, H; Vajente, G; Vallisneri, M; Vass, S; Vaulin, R; Vavoulidis, M; Vecchio, A; Vedovato, G; van Veggel, A A; Veitch, J; Veitch, P; Veltkamp, C; Verkindt, D; Vetrano, F; Viceré, A; Villar, A; Vinet, J-Y; Vocca, H; Vorvick, C; Vyachanin, S P; Waldman, S J; Wallace, L; Ward, H; Ward, R L; Was, M; Weidner, A; Weinert, M; Weinstein, A J; Weiss, R; Wen, L; Wen, S; Wette, K; Whelan, J T; Whitcomb, S E; Whiting, B F; Wilkinson, C; Willems, P A; Williams, H R; Williams, L; Willke, B; Wilmut, I; Winkelmann, L; Winkler, W; Wipf, C C; Wiseman, A G; Woan, G; Wooley, R; Worden, J; Wu, W; Yakushin, I; Yamamoto, H; Yan, Z; Yoshida, S; Yvert, M; Zanolin, M; Zhang, J; Zhang, L; Zhao, C; Zotov, N; Zucker, M E; Zweizig, J

    2009-08-20

    A stochastic background of gravitational waves is expected to arise from a superposition of a large number of unresolved gravitational-wave sources of astrophysical and cosmological origin. It should carry unique signatures from the earliest epochs in the evolution of the Universe, inaccessible to standard astrophysical observations. Direct measurements of the amplitude of this background are therefore of fundamental importance for understanding the evolution of the Universe when it was younger than one minute. Here we report limits on the amplitude of the stochastic gravitational-wave background using the data from a two-year science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). Our result constrains the energy density of the stochastic gravitational-wave background normalized by the critical energy density of the Universe, in the frequency band around 100 Hz, to be <6.9 x 10(-6) at 95% confidence. The data rule out models of early Universe evolution with relatively large equation-of-state parameter, as well as cosmic (super)string models with relatively small string tension that are favoured in some string theory models. This search for the stochastic background improves on the indirect limits from Big Bang nucleosynthesis and cosmic microwave background at 100 Hz.

  19. An upper limit on the stochastic gravitational-wave background of cosmological origin.

    PubMed

    Abbott, B P; Abbott, R; Acernese, F; Adhikari, R; Ajith, P; Allen, B; Allen, G; Alshourbagy, M; Amin, R S; Anderson, S B; Anderson, W G; Antonucci, F; Aoudia, S; Arain, M A; Araya, M; Armandula, H; Armor, P; Arun, K G; Aso, Y; Aston, S; Astone, P; Aufmuth, P; Aulbert, C; Babak, S; Baker, P; Ballardin, G; Ballmer, S; Barker, C; Barker, D; Barone, F; Barr, B; Barriga, P; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Bastarrika, M; Bauer, Th S; Behnke, B; Beker, M; Benacquista, M; Betzwieser, J; Beyersdorf, P T; Bigotta, S; Bilenko, I A; Billingsley, G; Birindelli, S; Biswas, R; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Bland, B; Boccara, C; Bodiya, T P; Bogue, L; Bondu, F; Bonelli, L; Bork, R; Boschi, V; Bose, S; Bosi, L; Braccini, S; Bradaschia, C; Brady, P R; Braginsky, V B; Brand, J F J van den; Brau, J E; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Van Den Broeck, C; Brooks, A F; Brown, D A; Brummit, A; Brunet, G; Bullington, A; Bulten, H J; Buonanno, A; Burmeister, O; Buskulic, D; Byer, R L; Cadonati, L; Cagnoli, G; Calloni, E; Camp, J B; Campagna, E; Cannizzo, J; Cannon, K C; Canuel, B; Cao, J; Carbognani, F; Cardenas, L; Caride, S; Castaldi, G; Caudill, S; Cavaglià, M; Cavalier, F; Cavalieri, R; Cella, G; Cepeda, C; Cesarini, E; Chalermsongsak, T; Chalkley, E; Charlton, P; Chassande-Mottin, E; Chatterji, S; Chelkowski, S; Chen, Y; Christensen, N; Chung, C T Y; Clark, D; Clark, J; Clayton, J H; Cleva, F; Coccia, E; Cokelaer, T; Colacino, C N; Colas, J; Colla, A; Colombini, M; Conte, R; Cook, D; Corbitt, T R C; Corda, C; Cornish, N; Corsi, A; Coulon, J-P; Coward, D; Coyne, D C; Creighton, J D E; Creighton, T D; Cruise, A M; Culter, R M; Cumming, A; Cunningham, L; Cuoco, E; Danilishin, S L; D'Antonio, S; Danzmann, K; Dari, A; Dattilo, V; Daudert, B; Davier, M; Davies, G; Daw, E J; Day, R; De Rosa, R; Debra, D; Degallaix, J; Del Prete, M; Dergachev, V; Desai, S; Desalvo, R; Dhurandhar, S; Di Fiore, L; Di Lieto, A; Di Paolo Emilio, M; Di Virgilio, A; Díaz, M; Dietz, A; Donovan, F; Dooley, K L; Doomes, E E; Drago, M; Drever, R W P; Dueck, J; Duke, I; Dumas, J-C; Dwyer, J G; Echols, C; Edgar, M; Effler, A; Ehrens, P; Ely, G; Espinoza, E; Etzel, T; Evans, M; Evans, T; Fafone, V; Fairhurst, S; Faltas, Y; Fan, Y; Fazi, D; Fehrmann, H; Ferrante, I; Fidecaro, F; Finn, L S; Fiori, I; Flaminio, R; Flasch, K; Foley, S; Forrest, C; Fotopoulos, N; Fournier, J-D; Franc, J; Franzen, A; Frasca, S; Frasconi, F; Frede, M; Frei, M; Frei, Z; Freise, A; Frey, R; Fricke, T; Fritschel, P; Frolov, V V; Fyffe, M; Galdi, V; Gammaitoni, L; Garofoli, J A; Garufi, F; Genin, E; Gennai, A; Gholami, I; Giaime, J A; Giampanis, S; Giardina, K D; Giazotto, A; Goda, K; Goetz, E; Goggin, L M; González, G; Gorodetsky, M L; Gobler, S; Gouaty, R; Granata, M; Granata, V; Grant, A; Gras, S; Gray, C; Gray, M; Greenhalgh, R J S; Gretarsson, A M; Greverie, C; Grimaldi, F; Grosso, R; Grote, H; Grunewald, S; Guenther, M; Guidi, G; Gustafson, E K; Gustafson, R; Hage, B; Hallam, J M; Hammer, D; Hammond, G D; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Haughian, K; Hayama, K; Heefner, J; Heitmann, H; Hello, P; Heng, I S; Heptonstall, A; Hewitson, M; Hild, S; Hirose, E; Hoak, D; Hodge, K A; Holt, K; Hosken, D J; Hough, J; Hoyland, D; Huet, D; Hughey, B; Huttner, S H; Ingram, D R; Isogai, T; Ito, M; Ivanov, A; Johnson, B; Johnson, W W; Jones, D I; Jones, G; Jones, R; Sancho de la Jordana, L; Ju, L; Kalmus, P; Kalogera, V; Kandhasamy, S; Kanner, J; Kasprzyk, D; Katsavounidis, E; Kawabe, K; Kawamura, S; Kawazoe, F; Kells, W; Keppel, D G; Khalaidovski, A; Khalili, F Y; Khan, R; Khazanov, E; King, P; Kissel, J S; Klimenko, S; Kokeyama, K; Kondrashov, V; Kopparapu, R; Koranda, S; Kozak, D; Krishnan, B; Kumar, R; Kwee, P; La Penna, P; Lam, P K; Landry, M; Lantz, B; Laval, M; Lazzarini, A; Lei, H; Lei, M; Leindecker, N; Leonor, I; Leroy, N; Letendre, N; Li, C; Lin, H; Lindquist, P E; Littenberg, T B; Lockerbie, N A; Lodhia, D; Longo, M; Lorenzini, M; Loriette, V; Lormand, M; Losurdo, G; Lu, P; Lubinski, M; Lucianetti, A; Lück, H; Machenschalk, B; Macinnis, M; Mackowski, J-M; Mageswaran, M; Mailand, K; Majorana, E; Man, N; Mandel, I; Mandic, V; Mantovani, M; Marchesoni, F; Marion, F; Márka, S; Márka, Z; Markosyan, A; Markowitz, J; Maros, E; Marque, J; Martelli, F; Martin, I W; Martin, R M; Marx, J N; Mason, K; Masserot, A; Matichard, F; Matone, L; Matzner, R A; Mavalvala, N; McCarthy, R; McClelland, D E; McGuire, S C; McHugh, M; McIntyre, G; McKechan, D J A; McKenzie, K; Mehmet, M; Melatos, A; Melissinos, A C; Mendell, G; Menéndez, D F; Menzinger, F; Mercer, R A; Meshkov, S; Messenger, C; Meyer, M S; Michel, C; Milano, L; Miller, J; Minelli, J; Minenkov, Y; Mino, Y; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Miyakawa, O; Moe, B; Mohan, M; Mohanty, S D; Mohapatra, S R P; Moreau, J; Moreno, G; Morgado, N; Morgia, A; Morioka, T; Mors, K; Mosca, S; Mossavi, K; Mours, B; Mowlowry, C; Mueller, G; Muhammad, D; Mühlen, H Zur; Mukherjee, S; Mukhopadhyay, H; Mullavey, A; Müller-Ebhardt, H; Munch, J; Murray, P G; Myers, E; Myers, J; Nash, T; Nelson, J; Neri, I; Newton, G; Nishizawa, A; Nocera, F; Numata, K; Ochsner, E; O'Dell, J; Ogin, G H; O'Reilly, B; O'Shaughnessy, R; Ottaway, D J; Ottens, R S; Overmier, H; Owen, B J; Pagliaroli, G; Palomba, C; Pan, Y; Pankow, C; Paoletti, F; Papa, M A; Parameshwaraiah, V; Pardi, S; Pasqualetti, A; Passaquieti, R; Passuello, D; Patel, P; Pedraza, M; Penn, S; Perreca, A; Persichetti, G; Pichot, M; Piergiovanni, F; Pierro, V; Pinard, L; Pinto, I M; Pitkin, M; Pletsch, H J; Plissi, M V; Poggiani, R; Postiglione, F; Principe, M; Prix, R; Prodi, G A; Prokhorov, L; Punken, O; Punturo, M; Puppo, P; Putten, S van der; Quetschke, V; Raab, F J; Rabaste, O; Rabeling, D S; Radkins, H; Raffai, P; Raics, Z; Rainer, N; Rakhmanov, M; Rapagnani, P; Raymond, V; Re, V; Reed, C M; Reed, T; Regimbau, T; Rehbein, H; Reid, S; Reitze, D H; Ricci, F; Riesen, R; Riles, K; Rivera, B; Roberts, P; Robertson, N A; Robinet, F; Robinson, C; Robinson, E L; Rocchi, A; Roddy, S; Rolland, L; Rollins, J; Romano, J D; Romano, R; Romie, J H; Röver, C; Rowan, S; Rüdiger, A; Ruggi, P; Russell, P; Ryan, K; Sakata, S; Salemi, F; Sandberg, V; Sannibale, V; Santamaría, L; Saraf, S; Sarin, P; Sassolas, B; Sathyaprakash, B S; Sato, S; Satterthwaite, M; Saulson, P R; Savage, R; Savov, P; Scanlan, M; Schilling, R; Schnabel, R; Schofield, R; Schulz, B; Schutz, B F; Schwinberg, P; Scott, J; Scott, S M; Searle, A C; Sears, B; Seifert, F; Sellers, D; Sengupta, A S; Sentenac, D; Sergeev, A; Shapiro, B; Shawhan, P; Shoemaker, D H; Sibley, A; Siemens, X; Sigg, D; Sinha, S; Sintes, A M; Slagmolen, B J J; Slutsky, J; van der Sluys, M V; Smith, J R; Smith, M R; Smith, N D; Somiya, K; Sorazu, B; Stein, A; Stein, L C; Steplewski, S; Stochino, A; Stone, R; Strain, K A; Strigin, S; Stroeer, A; Sturani, R; Stuver, A L; Summerscales, T Z; Sun, K-X; Sung, M; Sutton, P J; Swinkels, B L; Szokoly, G P; Talukder, D; Tang, L; Tanner, D B; Tarabrin, S P; Taylor, J R; Taylor, R; Terenzi, R; Thacker, J; Thorne, K A; Thorne, K S; Thüring, A; Tokmakov, K V; Toncelli, A; Tonelli, M; Torres, C; Torrie, C; Tournefier, E; Travasso, F; Traylor, G; Trias, M; Trummer, J; Ugolini, D; Ulmen, J; Urbanek, K; Vahlbruch, H; Vajente, G; Vallisneri, M; Vass, S; Vaulin, R; Vavoulidis, M; Vecchio, A; Vedovato, G; van Veggel, A A; Veitch, J; Veitch, P; Veltkamp, C; Verkindt, D; Vetrano, F; Viceré, A; Villar, A; Vinet, J-Y; Vocca, H; Vorvick, C; Vyachanin, S P; Waldman, S J; Wallace, L; Ward, H; Ward, R L; Was, M; Weidner, A; Weinert, M; Weinstein, A J; Weiss, R; Wen, L; Wen, S; Wette, K; Whelan, J T; Whitcomb, S E; Whiting, B F; Wilkinson, C; Willems, P A; Williams, H R; Williams, L; Willke, B; Wilmut, I; Winkelmann, L; Winkler, W; Wipf, C C; Wiseman, A G; Woan, G; Wooley, R; Worden, J; Wu, W; Yakushin, I; Yamamoto, H; Yan, Z; Yoshida, S; Yvert, M; Zanolin, M; Zhang, J; Zhang, L; Zhao, C; Zotov, N; Zucker, M E; Zweizig, J

    2009-08-20

    A stochastic background of gravitational waves is expected to arise from a superposition of a large number of unresolved gravitational-wave sources of astrophysical and cosmological origin. It should carry unique signatures from the earliest epochs in the evolution of the Universe, inaccessible to standard astrophysical observations. Direct measurements of the amplitude of this background are therefore of fundamental importance for understanding the evolution of the Universe when it was younger than one minute. Here we report limits on the amplitude of the stochastic gravitational-wave background using the data from a two-year science run of the Laser Interferometer Gravitational-wave Observatory (LIGO). Our result constrains the energy density of the stochastic gravitational-wave background normalized by the critical energy density of the Universe, in the frequency band around 100 Hz, to be <6.9 x 10(-6) at 95% confidence. The data rule out models of early Universe evolution with relatively large equation-of-state parameter, as well as cosmic (super)string models with relatively small string tension that are favoured in some string theory models. This search for the stochastic background improves on the indirect limits from Big Bang nucleosynthesis and cosmic microwave background at 100 Hz. PMID:19693079

  20. Recommendations for fluoride limits in drinking water based on estimated daily fluoride intake in the Upper East Region, Ghana.

    PubMed

    Craig, Laura; Lutz, Alexandra; Berry, Kate A; Yang, Wei

    2015-11-01

    Both dental and skeletal fluorosis caused by high fluoride intake are serious public health concerns around the world. Fluorosis is particularly pronounced in developing countries where elevated concentrations of naturally occurring fluoride are present in the drinking water, which is the primary route of exposure. The World Health Organization recommended limit of fluoride in drinking water is 1.5 mg F(-) L(-1), which is also the upper limit for fluoride in drinking water for several other countries such as Canada, China, India, Australia, and the European Union. In the United States the enforceable limit is much higher at 4 mg F(-) L(-1), which is intended to prevent severe skeletal fluorosis but does not protect against dental fluorosis. Many countries, including the United States, also have notably lower unenforced recommended limits to protect against dental fluorosis. One consideration in determining the optimum fluoride concentration in drinking water is daily water intake, which can be high in hot climates such as in northern Ghana. The results of this study show that average water intake is about two times higher in Ghana than in more temperate climates and, as a result, the fluoride intake is higher. The results also indicate that to protect the Ghanaian population against dental fluorosis, the maximum concentration of fluoride in drinking water for children under 6-8 years should be 0.6 mg F(-) L(-1) (and lower in the first two years of life), and the limit for older children and adults should be 1.0 mg F(-) L(-1). However, when considering that water treatment is not cost-free, the most widely recommended limit of 1.5 mg F(-) L(-1) - which is currently the limit in Ghana--may be appropriate for older children and adults since they are not vulnerable to dental fluorosis once the tooth enamel is formed.

  1. Recommendations for fluoride limits in drinking water based on estimated daily fluoride intake in the Upper East Region, Ghana.

    PubMed

    Craig, Laura; Lutz, Alexandra; Berry, Kate A; Yang, Wei

    2015-11-01

    Both dental and skeletal fluorosis caused by high fluoride intake are serious public health concerns around the world. Fluorosis is particularly pronounced in developing countries where elevated concentrations of naturally occurring fluoride are present in the drinking water, which is the primary route of exposure. The World Health Organization recommended limit of fluoride in drinking water is 1.5 mg F(-) L(-1), which is also the upper limit for fluoride in drinking water for several other countries such as Canada, China, India, Australia, and the European Union. In the United States the enforceable limit is much higher at 4 mg F(-) L(-1), which is intended to prevent severe skeletal fluorosis but does not protect against dental fluorosis. Many countries, including the United States, also have notably lower unenforced recommended limits to protect against dental fluorosis. One consideration in determining the optimum fluoride concentration in drinking water is daily water intake, which can be high in hot climates such as in northern Ghana. The results of this study show that average water intake is about two times higher in Ghana than in more temperate climates and, as a result, the fluoride intake is higher. The results also indicate that to protect the Ghanaian population against dental fluorosis, the maximum concentration of fluoride in drinking water for children under 6-8 years should be 0.6 mg F(-) L(-1) (and lower in the first two years of life), and the limit for older children and adults should be 1.0 mg F(-) L(-1). However, when considering that water treatment is not cost-free, the most widely recommended limit of 1.5 mg F(-) L(-1) - which is currently the limit in Ghana--may be appropriate for older children and adults since they are not vulnerable to dental fluorosis once the tooth enamel is formed. PMID:26058000

  2. An Upper Limit on the Albedo of HD 209458b: Direct Imaging Photometry with the MOST Satellite

    NASA Astrophysics Data System (ADS)

    Rowe, Jason F.; Matthews, Jaymie M.; Seager, Sara; Kuschnig, Rainer; Guenther, David B.; Moffat, Anthony F. J.; Rucinski, Slavek M.; Sasselov, Dimitar; Walker, Gordon A. H.; Weiss, Werner W.

    2006-08-01

    We present space-based photometry of the transiting exoplanetary system HD 209458 obtained with the Microvariablity and Oscillations of Stars (MOST) satellite, spanning 14 days and covering 4 transits and 4 secondary eclipses. The HD 209458 photometry was obtained in MOST's lower precision direct imaging mode, which is used for targets in the brightness range 6.5>=V>=13. We describe the photometric reduction techniques for this mode of observing, in particular the corrections for stray earthshine. We do not detect the secondary eclipse in the MOST data, to a limit in depth of 0.053 mmag (1 σ). We set a 1 σ upper limit on the planet-star flux ratio of 4.88×10-5 corresponding to a geometric albedo upper limit in the MOST bandpass (400-700 nm) of 0.25. The corresponding numbers at the 3 σ level are 1.34×10-4 and 0.68, respectively. HD 209458b is half as bright as Jupiter in the MOST bandpass. This low geometric albedo value is an important constraint for theoretical models of the HD 209458b atmosphere, in particular ruling out the presence of reflective clouds. A second MOST campaign on HD 209458 is expected to be sensitive to an exoplanet albedo as low as 0.13 (1 σ), if the star does not become more intrinsically variable in the meantime. MOST is a Canadian Space Agency mission, operated jointly by Dynacon, Inc., and the Universities of Toronto and British Columbia, with assistance from the University of Vienna.

  3. Plasticity of protective mechanisms only partially explains interactive effects of temperature and UVR on upper thermal limits.

    PubMed

    Kern, Pippa; Cramp, Rebecca L; Seebacher, Frank; Ghanizadeh Kazerouni, Ensiyeh; Franklin, Craig E

    2015-12-01

    Temperature and ultraviolet radiation (UVR) are key environmental drivers that are linked in their effects on cellular damage. Exposure to both high temperatures and UVR can cause cellular damage that result in the up-regulation of common protective mechanisms, such as the induction of heat shock proteins (Hsps) and antioxidants. As such, the interactive effects of these stressors at the cellular level may determine physiological limits, such as thermal tolerance. Furthermore, antioxidant activity is often thermally sensitive, which may lead to temperature dependent effects of UVR exposure. Here we examined the interactive effects of temperature and UVR on upper thermal limits, Hsp70 abundance, oxidative damage and antioxidant (catalase) activity. We exposed Limnodynastes peronii tadpoles to one of three temperature treatments (constant 18°C, constant 28°C and daily fluctuations between 18 and 28°C) in the presence or absence of UVR. Tadpoles were tested for upper thermal limits (CTmax), induction of Hsp70, oxidative damage and catalase activity. Our results show that CTmax was influenced by an interactive effect between temperature and UVR treatment. For tadpoles kept in cold temperatures, exposure to UVR led to cross-tolerance to high temperatures, increasing CTmax. Plasticity in this trait was not fully explained by changes in the lower level mechanistic traits examined. These results highlight the difficulty in predicting the mechanistic basis for the interactive effects of multiple stressors on whole animal traits. Multifactorial studies may therefore be required to understand how complex mechanistic processes shape physiological tolerances, and determine responses to environmental variation. PMID:26408107

  4. An upper limit on the contribution of accreting white dwarfs to the type Ia supernova rate.

    PubMed

    Gilfanov, Marat; Bogdán, Akos

    2010-02-18

    There is wide agreement that type Ia supernovae (used as standard candles for cosmology) are associated with the thermonuclear explosions of white dwarf stars. The nuclear runaway that leads to the explosion could start in a white dwarf gradually accumulating matter from a companion star until it reaches the Chandrasekhar limit, or could be triggered by the merger of two white dwarfs in a compact binary system. The X-ray signatures of these two possible paths are very different. Whereas no strong electromagnetic emission is expected in the merger scenario until shortly before the supernova, the white dwarf accreting material from the normal star becomes a source of copious X-rays for about 10(7) years before the explosion. This offers a means of determining which path dominates. Here we report that the observed X-ray flux from six nearby elliptical galaxies and galaxy bulges is a factor of approximately 30-50 less than predicted in the accretion scenario, based upon an estimate of the supernova rate from their K-band luminosities. We conclude that no more than about five per cent of type Ia supernovae in early-type galaxies can be produced by white dwarfs in accreting binary systems, unless their progenitors are much younger than the bulk of the stellar population in these galaxies, or explosions of sub-Chandrasekhar white dwarfs make a significant contribution to the supernova rate. PMID:20164924

  5. An upper limit to the interstellar C5 abundance in translucent clouds

    NASA Astrophysics Data System (ADS)

    Galazutdinov, G.; Pětlewski, A.; Musaev, F.; Moutou, C.; Lo Curto, G.; Krełowski, J.

    2002-11-01

    We have analyzed high resolution spectra of several slightly to moderately reddened stars collected at two observatories: ESO (La Silla) and Terskol (Northern Caucasia), to estimate the abundance of the C5 molecule in the interstellar medium. We confirm the presence of a feature near 4975 Å which appears to be a weak DIB rather than the predicted C5 band since the origin band near 5109 Å remains invisible even in spectra of high signal-to-noise ratio ( ~ 2500) and spectral resolution (R ~ 220 000). This confirms that the C5 abundance in translucent interstellar clouds is very low. We estimate its limit as low as 1011 cm-2 in the scale E(B-V)=0.35 for ``zeta" type objects that is two times lower than that of Maier et al. (2002). Based on data collected at the ESO 3.6 m telescope operated on La Silla Observatory, Chile and 2-m telescope of the Terskol Observatory, Russia.

  6. Upper Temperature Limit of Environmental Barrier Coatings Based on Mullite and BSAS

    NASA Technical Reports Server (NTRS)

    Lee, Kang N.; Fox, Dennis S.; Eldridge, Jeffrey I.; Zhu, Dongming; Bansal, Narottam P.; Miller, Robert A.; Robinson, Raymond C.

    2002-01-01

    Current state-of-the-art environmental barrier coatings (EBCs) for Si-based ceramics consist of three layers: a silicon bond coat, an intermediate mullite (3Al2O3-2SiO2) or mullite + BSAS (1-xBaO-xSrO-Al2O3-2SiO2) layer, and a BSAS top coat. Areas of concern for long-term durability are environmental durability, chemical compatibility, silica volatility, phase stability, and thermal conductivity. Variants of this family of EBCs were applied to monolithic SiC and melt infiltrated SiC/SiC composites. Reaction between BSAS and silica results in low melting (approx. 1300 C) glasses at T > 1400 C, which can cause the spallation of the EBC. At temperatures greater than 1400 C, the BSAS top coat also degrades by formation of a porous structure, and it suffers significant recession via silica volatilization in water vapor-containing atmospheres. All of these degradation mechanisms can be EBC life-limiting factors. BSAS undergoes a very sluggish phase transformation (hexagonal celsian to monoclinic celsian), the implications of which are not fully understood at this point. There was evidence of rapid sintering at temperatures as low as 1300 C, as inferred from the sharp increase in thermal conductivity.

  7. An upper limit on the contribution of accreting white dwarfs to the type Ia supernova rate.

    PubMed

    Gilfanov, Marat; Bogdán, Akos

    2010-02-18

    There is wide agreement that type Ia supernovae (used as standard candles for cosmology) are associated with the thermonuclear explosions of white dwarf stars. The nuclear runaway that leads to the explosion could start in a white dwarf gradually accumulating matter from a companion star until it reaches the Chandrasekhar limit, or could be triggered by the merger of two white dwarfs in a compact binary system. The X-ray signatures of these two possible paths are very different. Whereas no strong electromagnetic emission is expected in the merger scenario until shortly before the supernova, the white dwarf accreting material from the normal star becomes a source of copious X-rays for about 10(7) years before the explosion. This offers a means of determining which path dominates. Here we report that the observed X-ray flux from six nearby elliptical galaxies and galaxy bulges is a factor of approximately 30-50 less than predicted in the accretion scenario, based upon an estimate of the supernova rate from their K-band luminosities. We conclude that no more than about five per cent of type Ia supernovae in early-type galaxies can be produced by white dwarfs in accreting binary systems, unless their progenitors are much younger than the bulk of the stellar population in these galaxies, or explosions of sub-Chandrasekhar white dwarfs make a significant contribution to the supernova rate.

  8. Teaching Absolute Value Meaningfully

    ERIC Educational Resources Information Center

    Wade, Angela

    2012-01-01

    What is the meaning of absolute value? And why do teachers teach students how to solve absolute value equations? Absolute value is a concept introduced in first-year algebra and then reinforced in later courses. Various authors have suggested instructional methods for teaching absolute value to high school students (Wei 2005; Stallings-Roberts…

  9. Stability of cable thermocouples at the upper temperature limit of their working range

    NASA Astrophysics Data System (ADS)

    Ulanovskiy, A. A.; Zemba, E. S.; Belenkiy, A. M.; Chibizova, S. I.; Bursin, A. N.

    2013-09-01

    Experimental results of EMF stability research are presented for MIMS thermocouples of types K and N of external diameters 1.5; 3.0 and 5.0 mm. All thermocouples had heat resistant sheath and were not used before the tests. They were subjected to every-day cyclic heating and cooling. During each cycle there was 6 h annealing in air at the temperature 1200 °C Results shows, that stability of a cable thermocouple in air at the temperature 1200 °C depends, mainly, on its diameter, instead of on thermocouple type or metal sheath material. Acceptable time of operation in a thermal cycling mode for 1.5 mm cable thermocouples is limited by (15, 16) h, and for 3 mm thermocouples it is equal to (40, 45) h. Besides, the effect of signal shunting is shown in the work for a thermocouple under heating of its average part to the temperature 1200 °C Experiment has shown that use of long cable thermocouple of 1.5 mm diameter at the temperatures above 1000°C can lead to serious errors in temperature measurement. Heating of 400 mm thermocouple length to 1100 °C causes positive EMF in the 1.5 mm cable thermocouple equivalent to +3.4 °C and +18 °C at 1200°C. For 3 mm cable thermocouple EMF at 1200 °C reaches the value equivalent to +2.3 °C, but double increase in heating length makes the value greater to +13.5 °C. The given facts are necessary to consider while using of thin (1, 3) mm cable thermocouples at the temperatures (1100, 1200) °C.

  10. Upper airway collapsibility and patterns of flow limitation at constant end-expiratory lung volume.

    PubMed

    Owens, Robert L; Edwards, Bradley A; Sands, Scott A; Butler, James P; Eckert, Danny J; White, David P; Malhotra, Atul; Wellman, Andrew

    2012-09-01

    The passive pharyngeal critical closing pressure (Pcrit) is measured using a series of pressure drops. However, pressure drops also lower end-expiratory lung volume (EELV), which independently affects Pcrit. We describe a technique to measure Pcrit at a constant EELV. Continuous positive airway pressure (CPAP)-treated obstructive sleep apnea (OSA) patients and controls were instrumented with an epiglottic catheter, magnetometers (to measure change in EELV), and nasal mask/pneumotachograph and slept supine on nasal CPAP. Pcrit was measured in standard fashion and using our novel "biphasic technique" in which expiratory pressure only was lowered for 1 min before the inspiratory pressure was dropped; this allowed EELV to decrease to the drop level before performing the pressure drop. Seven OSA and three controls were studied. The biphasic technique successfully lowered EELV before the inspiratory pressure drop. Pcrit was similar between the standard and biphasic techniques (-0.4 ± 2.6 vs. -0.6 ± 2.3 cmH(2)O, respectively, P = 0.84). Interestingly, we noted three different patterns of flow limitation: 1) classic Starling resistor type: flow fixed and independent of downstream pressure; 2) negative effort dependence within breaths: substantial decrease in flow, sometimes with complete collapse, as downstream pressure decreased; and 3) and negative effort dependence across breaths: progressive reductions in peak flow as respiratory effort on successive breaths increased. Overall, EELV changes do not influence standard passive Pcrit measurements if breaths 3-5 of pressure drops are used. These results also highlight the importance of inspiratory collapse in OSA pathogenesis. The cause of negative effort dependence within and across breaths is not known and requires further study. PMID:22628372

  11. Calculation of Upper Subcritical Limits for Nuclear Criticality in a Repository

    SciTech Connect

    J.W. Pegram

    1998-07-29

    The purpose of this document is to present the methodology to be used for development of the Subcritical Limit (SL) for post closure conditions for the Yucca Mountain repository. The SL is a value based on a set of benchmark criticality multiplier, k{sub eff} results that are outputs of the MCNP calculation method. This SL accounts for calculational biases and associated uncertainties resulting from the use of MCNP as the method of assessing k{sub eff}. The context for an SL estimate include the range of applicability (based on the set of MCNP results) and the type of SL required for the application at hand. This document will include illustrative calculations for each of three approaches. The data sets used for the example calculations are identified in Section 5.1. These represent three waste categories, and SLs for each of these sets of experiments will be computed in this document. Future MCNP data sets will be analyzed using the methods discussed here. The treatment of the biases evaluated on sets of k{sub eff} results via MCNP is statistical in nature. This document does not address additional non-statistical contributions to the bias margin, acknowledging that regulatory requirements may impose additional administrative penalties. Potentially, there are other biases or margins that should be accounted for when assessing criticality (k{sub eff}). Only aspects of the bias as determined using the stated assumptions and benchmark critical data sets will be included in the methods and sample calculations in this document. The set of benchmark experiments used in the validation of the computational system should be representative of the composition, configuration, and nuclear characteristics for the application at hand. In this work, a range of critical experiments will be the basis of establishing the SL for three categories of waste types that will be in the repository. The ultimate purpose of this document is to present methods that will effectively

  12. Electric Mars: The first direct measurement of an upper limit for the Martian "polar wind" electric potential

    NASA Astrophysics Data System (ADS)

    Collinson, Glyn; Mitchell, David; Glocer, Alex; Grebowsky, Joseph; Peterson, W. K.; Connerney, Jack; Andersson, Laila; Espley, Jared; Mazelle, Christian; Sauvaud, Jean-André; Fedorov, Andrei; Ma, Yingjuan; Bougher, Steven; Lillis, Robert; Ergun, Robert; Jakosky, Bruce

    2015-11-01

    An important mechanism in the generation of polar wind outflow is the ambipolar electric potential which assists ions in overcoming gravity and is a key mechanism for Terrestrial ionospheric escape. At Mars, open field lines are not confined to the poles, and outflow of ionospheric electrons is observed far into the tail. It has thus been hypothesized that a similar electric potential may be present at Mars, contributing to global ionospheric loss. However, no direct measurements of this potential have been made. In this pilot study, we examine photoelectron spectra measured by the Solar Wind Electron Analyzer instrument on the NASA Mars Atmosphere and Volatile EvolutioN (MAVEN) Mars Scout to put an initial upper bound on the total potential drop in the ionosphere of Mars of Φ♂ ≾⊥ 2V , with the possibility of a further ≾4.5 V potential drop above this in the magnetotail. If the total potential drop was close to the upper limit, then strong outflows of major ionospheric species (H+, O+, and O2+) would be expected. However, if most of the potential drop is confined below the spacecraft, as expected by current theory, then such a potential would not be sufficient on its own to accelerate O2+ to escape velocities, but would be sufficient for lighter ions. However, any potential would contribute to atmospheric loss through the enhancement of Jeans escape.

  13. Discovery of a Doppler-limited CO line in the upper mesosphere of Venus - A new dynamical probe

    NASA Technical Reports Server (NTRS)

    Buhl, David; Chin, Gordon; Goldstein, Jeffrey J.

    1991-01-01

    The presence of CO in the upper atmosphere of Venus is a consequence of the photochemistry of CO2, the dominant atmospheric constituent. In December 1989 the J = 1-2 transition of CO was observed at 230 GHz. In addition to the broad absorption line first reported by Kakar et al. (1976), a narrow absorption feature at the center of the line due to upper mesospheric CO, where the temperature profile starts to exhibit diurnal variation with altitude. The narrow feature is approximately 600 kHz wide and is predominantly Doppler-broadened. The Doppler core provides a new means of measuring wind velocities at these altitudes in the atmosphere of Venus. Detection of small Doppler shifts in the line core can in principle be used to measure winds with an accuracy of 10 m/s. Results are presently limited by the 17 kHz uncertainty in the measured rest frequency, corresponding to a systematic error in wind velocity up to 22 m/s, and the absence of laboratory measurements of the pressure shift in CO by CO2.

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

    NASA Technical Reports Server (NTRS)

    Dugan, J. V., Jr.

    1972-01-01

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

  15. Upper limits for the ethyl-cyanide abundances in TMC-1 and L134N - Chemical implications

    NASA Technical Reports Server (NTRS)

    Minh, Y. C.; Irvine, W. M.

    1991-01-01

    Interstellar ethyl-cyanide has been sought via its 2(02)-1(01) transition towards two cold, dark clouds, and upper limits of the total column densities of 3 x 10 to the 12th/sq cm and 2 x 10 to the 12th/sq cm for TMC-1 and L134N, respectively. The 2(02)-1(01) transition of vynil cyanide, previously identified in TMC-1 by Matthews and Sears (1983b), was also observed. The detection of vinyl cyanide and the nondetection of ethyl cyanide in TMC-1 are consistent with gas phase ion-molecule chemical models, and there is thus no necessity of invoking grain surface synthesis for vinyl cyanide in cold clouds.

  16. An upper limit to the energy of gamma-ray bursts indicates that GRBs/SNe are powered by magnetars

    NASA Astrophysics Data System (ADS)

    Mazzali, P. A.; McFadyen, A. I.; Woosley, S. E.; Pian, E.; Tanaka, M.

    2014-09-01

    The kinetic energy of supernovae (SNe) accompanied by gamma-ray bursts (GRBs) tends to cluster near 1052 erg, with 2 × 1052 erg an upper limit to which no compelling exceptions are found (assuming a certain degree of asphericity), and it is always significantly larger than the intrinsic energy of the GRB themselves (corrected for jet collimation). This energy is strikingly similar to the maximum rotational energy of a neutron star rotating with period 1 ms. It is therefore proposed that all GRBs associated with luminous SNe are produced by magnetars. GRBs that result from black hole formation (collapsars) may not produce luminous SNe. X-ray flashes, which are associated with less energetic SNe, are produced by neutron stars with weaker magnetic field or lower spin.

  17. Upper limits for the ethyl-cyanide abundances in TMC-1 and L134N: chemical implications.

    PubMed

    Minh, Y C; Irvine, W M

    1991-01-01

    We have sought interstellar ethyl-cyanide via its 2(02)-1(01) transition towards two cold, dark clouds and report upper limits of the total column densities of 3 x 10(12) cm-2 and 2 x 10(12) cm-2 for TMC-1 and L134N, respectively. We also observed the 2(02)-1(01) transition of vinyl cyanide previously identified in TMC-1 by Matthews and Sears (1983b). The detection of vinyl cyanide and the non-detection of ethyl cyanide in TMC-1 are consistent with gas phase ion-molecule chemical models, and there is thus no necessity of invoking grain surface synthesis for vinyl cyanide in cold clouds.

  18. Upper limits for the photoproduction cross section for the Φ⁻⁻(1860) pentaquark state off the deuteron

    SciTech Connect

    Egiyan, H.; Langheinrich, J.; Gothe, R. W.; Graham, L.; Holtrop, M.; Lu, H.; Mattione, P.; Mutchler, G.; Park, K.; Smith, E. S.; Stepanyan, S.; Zhao, Z. W.; Adhikari, K. P.; Aghasyan, M.; Anghinolfi, M.; Baghdasaryan, H.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Bedlinskiy, I.; Bennett, R. P.; Biselli, A. S.; Bookwalter, C.; Branford, D.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Contalbrigo, M.; D’Angelo, A.; Daniel, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Dey, B.; Dickson, R.; Djalali, C.; Doughty, D.; Dupre, R.; El Alaoui, A.; El Fassi, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fradi, A.; Gabrielyan, M. Y.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Gohn, W.; Golovatch, E.; Griffioen, K. A.; Guidal, M.; Guler, N.; Guo, L.; Gyurjyan, V.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Heddle, D.; Hicks, K.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jo, H. S.; Joo, K.; Khetarpal, P.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuleshov, S. V.; Livingston, K.; MacGregor, I. J. D.; Mao, Y.; Mayer, M.; McKinnon, B.; Mokeev, V.; Munevar, E.; Nadel-Turonski, P.; Ni, A.; Niculescu, G.; Ostrovidov, A. I.; Paolone, M.; Pappalardo, L.; Paremuzyan, R.; Park, S.; Pasyuk, E.; Anefalos Pereira, S.; Phelps, E.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Protopopescu, D.; Raue, B. A.; Ricco, G.; Rimal, D.; Ripani, M.; Ritchie, B. G.; Rosner, G.; Rossi, P.; Sabatié, F.; Saini, M. S.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Seraydaryan, H.; Sharabian, Y. G.; Smith, G. D.; Sober, D. I.; Stepanyan, S. S.; Strauch, S.; Taiuti, M.; Tang, W.; Taylor, C. E.; Tedeschi, D. J.; Ungaro, M.; Voutier, E.; Watts, D. P.; Weinstein, L. B.; Weygand, D. P.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhao, B.

    2012-01-30

    We searched for the Φ⁻⁻(1860) pentaquark in the photoproduction process off the deuteron in the Ξ⁻π⁻-decay channel using CLAS. The invariant-mass spectrum of the Ξ⁻π⁻ system does not indicate any statistically significant enhancement near the reported mass M=1.860 GeV. The statistical analysis of the sideband-subtracted mass spectrum yields a 90%-confidence-level upper limit of 0.7 nb for the photoproduction cross section of Φ⁻⁻(1860) with a consecutive decay intoΞ⁻π⁻ in the photon-energy range 4.5GeVγ<5.5GeV.

  19. Upper limits to the quiet-time solar neutron flux from 10 to 100 MeV

    NASA Technical Reports Server (NTRS)

    Moon, S.; Simnett, G. M.; White, R. S.

    1975-01-01

    The UCR large area solid-angle double scatter neutron telescope was flown to search for solar neutrons on 3 balloon flights on September 26, 1971, May 14, 1972 and September 19, 1972. The first two flights were launched from Palestine, Texas and the third from Cape Girardeau, Missouri. The float altitude on each flight was at about 5 g/sq cm residual atmosphere. Neutrons from 10 to 100 MeV were measured. No solar flares occurred during the flights. Upper limits to the quiet time solar neutron fluxes at the 95% confidence level are .00028, .00046, .00096 and .00090 neutrons/sq cm-sec in the energy intervals of 10-30, 30-50, 50-100 and 10-100 MeV, respectively.

  20. Upper limits for the photoproduction cross section for the Φ⁻⁻(1860) pentaquark state off the deuteron

    DOE PAGES

    Egiyan, H.; Langheinrich, J.; Gothe, R. W.; Graham, L.; Holtrop, M.; Lu, H.; Mattione, P.; Mutchler, G.; Park, K.; Smith, E. S.; et al

    2012-01-30

    We searched for the Φ⁻⁻(1860) pentaquark in the photoproduction process off the deuteron in the Ξ⁻π⁻-decay channel using CLAS. The invariant-mass spectrum of the Ξ⁻π⁻ system does not indicate any statistically significant enhancement near the reported mass M=1.860 GeV. The statistical analysis of the sideband-subtracted mass spectrum yields a 90%-confidence-level upper limit of 0.7 nb for the photoproduction cross section of Φ⁻⁻(1860) with a consecutive decay intoΞ⁻π⁻ in the photon-energy range 4.5GeVγ<5.5GeV.

  1. An Upper Limit on the Ratio Between the Extreme Ultraviolet and the Bolometric Luminosities of Stars Hosting Habitable Planets

    NASA Astrophysics Data System (ADS)

    Sengupta, Sujan

    2016-06-01

    A large number of terrestrial planets in the classical habitable zone of stars of different spectral types have already been discovered and many are expected to be discovered in the near future. However, owing to the lack of knowledge on the atmospheric properties, the ambient environment of such planets are unknown. It is known that sufficient amount of Extreme Ultraviolet (EUV) radiation from the star can drive hydrodynamic outflow of hydrogen that may drag heavier species from the atmosphere of the planet. If the rate of mass loss is sufficiently high, then substantial amount of volatiles would escape causing the planet to become uninhabitable. Considering energy-limited hydrodynamical mass loss with an escape rate that causes oxygen to escape alongwith hydrogen, an upper limit for the ratio between the EUV and the bolometric luminosities of stars which constrains the habitability of planets around them is presented here. Application of the limit to planet-hosting stars with known EUV luminosities implies that many M-type of stars should not have habitable planets around them.

  2. Water relations and microclimate around the upper limit of a cloud forest in Maui, Hawai'i.

    PubMed

    Gotsch, Sybil G; Crausbay, Shelley D; Giambelluca, Thomas W; Weintraub, Alexis E; Longman, Ryan J; Asbjornsen, Heidi; Hotchkiss, Sara C; Dawson, Todd E

    2014-07-01

    The goal of this study was to determine the effects of atmospheric demand on both plant water relations and daily whole-tree water balance across the upper limit of a cloud forest at the mean base height of the trade wind inversion in the tropical trade wind belt. We measured the microclimate and water relations (sap flow, water potential, stomatal conductance, pressure-volume relations) of Metrosideros polymorpha Gaudich. var. polymorpha in three habitats bracketing the cloud forest's upper limit in Hawai'i to understand the role of water relations in determining ecotone position. The subalpine shrubland site, located 100 m above the cloud forest boundary, had the highest vapor pressure deficit, the least amount of rainfall and the highest levels of nighttime transpiration (EN) of all three sites. In the shrubland site, on average, 29% of daily whole-tree transpiration occurred at night, while on the driest day of the study 50% of total daily transpiration occurred at night. While EN occurred in the cloud forest habitat, the proportion of total daily transpiration that occurred at night was much lower (4%). The average leaf water potential (Ψleaf) was above the water potential at the turgor loss point (ΨTLP) on both sides of the ecotone due to strong stomatal regulation. While stomatal closure maintained a high Ψleaf, the minimum leaf water potential (Ψleafmin) was close to ΨTLP, indicating that drier conditions may cause drought stress in these habitats and may be an important driver of current landscape patterns in stand density.

  3. Is the Growth of Birch at the UPPER Timberline in the Himalayas Limited By Moisture or By Temperature?

    NASA Astrophysics Data System (ADS)

    Liang, E.; Dawadi, B.; Pederson, N.; Eckstein, D.

    2014-12-01

    Birch (Betula) trees and forests are found across much of the temperate and boreal zones of the Northern Hemisphere. Yet, despite being an ecologically-significant genus, it is much less-well studied compared to common genera like Pinus, Picea, Juniperus, Quercus, and Fagus. In the Himalayas, Himalayan birch (Betula utilis) is a widespread, important broadleaf timberline species that survives in mountain rain shadows via access to water from snowmelt. Because precipitation in the Nepalese Himalayas decreases with increasing elevation, we hypothesized that the growth of birch at the upper timberlines between 3,900 and 4,150 m a.s.l. is primarily limited by moisture availability rather than by low temperature. To verify this assumption, a total of 292 increment cores were extracted from 211 birch trees at nine timberline sites. The synchronous occurrence of narrow rings and high inter-series correlations within and among sites evidenced a reliable cross-dating and a common climatic signal in the tree-ring widths variations. From March-May, all nine tree-ring width site chronologies showed a strongly positive response to total precipitation and a less strongly negative response to temperature. During the instrumental meteorological record (after 1960), years with a high percentage of missing rings coincided with pre-monsoon drought events. Periods of below-average growth are in phase with well-known drought events all over monsoon Asia, showing additional evidence that Himalayan birch growth at the upper timberlines is persistently limited by moisture availability. Our study describes the rare case of a drought-induced altitudinal timberline that is composed by a broadleaf tree species.

  4. WARM JUPITERS NEED CLOSE ''FRIENDS'' FOR HIGH-ECCENTRICITY MIGRATION—A STRINGENT UPPER LIMIT ON THE PERTURBER'S SEPARATION

    SciTech Connect

    Dong, Subo; Katz, Boaz; Socrates, Aristotle

    2014-01-20

    We propose a stringent observational test on the formation of warm Jupiters (gas-giant planets with 10 days ≲ P ≲ 100 days) by high-eccentricity (high-e) migration mechanisms. Unlike hot Jupiters, the majority of observed warm Jupiters have pericenter distances too large to allow efficient tidal dissipation to induce migration. To access the close pericenter required for migration during a Kozai-Lidov cycle, they must be accompanied by a strong enough perturber to overcome the precession caused by general relativity, placing a strong upper limit on the perturber's separation. For a warm Jupiter at a ∼ 0.2 AU, a Jupiter-mass (solar-mass) perturber is required to be ≲ 3 AU (≲ 30 AU) and can be identified observationally. Among warm Jupiters detected by radial velocities (RVs), ≳ 50% (5 out of 9) with large eccentricities (e ≳ 0.4) have known Jovian companions satisfying this necessary condition for high-e migration. In contrast, ≲ 20% (3 out of 17) of the low-e (e ≲ 0.2) warm Jupiters have detected additional Jovian companions, suggesting that high-e migration with planetary perturbers may not be the dominant formation channel. Complete, long-term RV follow-ups of the warm-Jupiter population will allow a firm upper limit to be put on the fraction of these planets formed by high-e migration. Transiting warm Jupiters showing spin-orbit misalignments will be interesting to apply our test. If the misalignments are solely due to high-e migration as commonly suggested, we expect that the majority of warm Jupiters with low-e (e ≲ 0.2) are not misaligned, in contrast with low-e hot Jupiters.

  5. An upper limit to the photon fraction in cosmic rays above 10**19-eV from the Pierre Auger Observatory

    SciTech Connect

    Abraham, J.; Aglietta, M.; Aguirre, C.; Allard, D.; Allekotte, I.; Allison, P.; Alvarez, C.; Alvarez-Muniz, J.; Ambrosio, M.; Anchordoqui, L.; Anjos, J.C.; /Centro Atomico Bariloche /Buenos Aires, CONICET /La Plata U. /Pierre Auger Observ. /CNEA, San Martin /Adelaide U. /Catholic U. of Bolivia, La Paz /Bolivia U. /Sao Paulo U. /Campinas State U. /UEFS, Feira de Santana

    2006-06-01

    An upper limit of 16% (at 95% c.l.) is derived for the photon fraction in cosmic rays with energies above 10{sup 19} eV, based on observations of the depth of shower maximum performed with the hybrid detector of the Pierre Auger Observatory. This is the first such limit on photons obtained by observing the fluorescence light profile of air showers. This upper limit confirms and improves on previous results from the Haverah Park and AGASA surface arrays. Additional data recorded with the Auger surface detectors for a subset of the event sample, support the conclusion that a photon origin of the observed events is not favored.

  6. Increasing the upper-limit intensity and temperature range for thermal self-focusing of a laser beam by using plasma density ramp-up

    SciTech Connect

    Bokaei, B.; Niknam, A. R.

    2014-03-15

    This work is devoted to improving relativistic and ponderomotive thermal self-focusing of the intense laser beam in an underdense plasma. It is shown that the ponderomotive nonlinearity induces a saturation mechanism for thermal self-focusing. Therefore, in addition to the well-known lower-limit critical intensity, there is an upper-limit intensity for thermal self-focusing above which the laser beam starts to experience ponderomotive defocusing. It is indicated that the upper-limit intensity value is dependent on plasma and laser parameters such as the plasma electron temperature, plasma density, and laser spot size. Furthermore, the effect of the upward plasma density ramp profile on the thermal self-focusing is studied. Results show that by using the plasma density ramp-up, the upper-limit intensity increases and the self-focusing temperature range expands.

  7. Eosinophil count - absolute

    MedlinePlus

    Eosinophils; Absolute eosinophil count ... the white blood cell count to give the absolute eosinophil count. ... than 500 cells per microliter (cells/mcL). Normal value ranges may vary slightly among different laboratories. Talk ...

  8. The He I 2.06 microns/Br-gamma ratio in starburst galaxies - An objective constraint on the upper mass limit to the initial mass function

    NASA Technical Reports Server (NTRS)

    Doyon, Rene; Puxley, P. J.; Joseph, R. D.

    1992-01-01

    The use of the He I 2.06 microns/Br-gamma ratio as a constraint on the massive stellar population in star-forming galaxies is developed. A theoretical relationship between the He I 2.06 microns/Br-gamma ratio and the effective temperature of the exciting star in H II regions is derived. The effects of collisional excitation and dust within the nebula on the ratio are also considered. It is shown that the He I 2.06 microns/Br-gamma ratio is a steep function of the effective temperature, a property which can be used to determine the upper mass limit of the initial mass function (IMF) in galaxies. This technique is reliable for upper mass limits less than about 40 solar masses. New near-infrared spectra of starburst galaxies are presented. The He I 2.06 microns/Br-gamma ratios observed imply a range of upper mass limits from 27 to over 40 solar masses. There is also evidence that the upper mass limit is spatially dependent within a given galaxy. These results suggest that the upper mass limit is not a uniquely defined parameter of the IMF and probably varies with local physical conditions.

  9. Upper limit for the D2H+ ortho-to-para ratio in the prestellar core 16293E (CHESS)

    NASA Astrophysics Data System (ADS)

    Vastel, C.; Caselli, P.; Ceccarelli, C.; Bacmann, A.; Lis, D. C.; Caux, E.; Codella, C.; Beckwith, J. A.; Ridley, T.

    2012-11-01

    The H_3^+ ion plays a key role in the chemistry of dense interstellar gas clouds where stars and planets are forming. The low temperatures and high extinctions of such clouds make direct observations of H_3^+ impossible, but lead to large abundances of H2D+ and D2H+, which are very useful probes of the early stages of star and planet formation. The ground-state rotational ortho-D2H+ 11,1-00,0 transition at 1476.6 GHz in the prestellar core 16293E has been searched for with the Herschel HIFI instrument, within the CHESS (Chemical HErschel Surveys of Star forming regions) Key Program. The line has not been detected at the 21 mK km s-1 level (3σ integrated line intensity). We used the ortho-H2D+ 11,0-11,1 transition and para-D2H+ 11,0-10,1 transition detected in this source to determine an upper limit on the ortho-to-para D2H+ ratio as well as the para-D2H+/ortho-H2D+ ratio from a non-local thermodynamic equilibrium analysis. The comparison between our chemical modeling and the observations suggests that the CO depletion must be high (larger than 100), with a density between 5 × 105 and 106 cm-3. Also the upper limit on the ortho-D2H+ line is consistent with a low gas temperature (~11 K) with a ortho-to-para ratio of 6 to 9, i.e. 2 to 3 times higher than the value estimated from the chemical modeling, making it impossible to detect this high frequency transition with the present state of the art receivers. The chemical network is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/547/A33Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

  10. Upper limits to the detection of ammonia from protoplanetary disks around HL Tauri and L1551-IRS 5

    NASA Technical Reports Server (NTRS)

    Gomez, Jose F.; Torrelles, Jose M.; Ho, Paul T. P.; Rodriguez, Luis F.; Canto, Jorge

    1993-01-01

    We present NH3(1, 1) and (2, 2) observations of the young stellar sources HL Tau and L1551-IRS 5 using the VLA in its B-configuration, which provides an angular resolution of about 0.4 arcsec (about 50 AU at 140 pc) at 1.3 cm wavelength. Our goal was to detect and resolve circumstellar molecular disks with radius of the order of 100 AU around these two sources. No ammonia emission was detected toward either of them. The 3-sigma levels were 2.7 mJy/beam and 3.9 mJy/beam for HL Tau and L1551-IRS 5, respectively, with a velocity resolution of about 5 km/s. With this nondetection, we estimate upper limits to the mass of the proposed protoplanetary molecular disks (within a radius of 10 AU from the central stars) on the order of 0.02/(X(NH3)/10 exp -8) solar mass for HL Tau and 0.1/(X(NH3)/10 exp -8) solar mass for L1551-IRS 5.

  11. The sea urchin Lytechinus variegatus lives close to the upper thermal limit for early development in a tropical lagoon.

    PubMed

    Collin, Rachel; Chan, Kit Yu Karen

    2016-08-01

    Thermal tolerance shapes organisms' physiological performance and limits their biogeographic ranges. Tropical terrestrial organisms are thought to live very near their upper thermal tolerance limits, and such small thermal safety factors put them at risk from global warming. However, little is known about the thermal tolerances of tropical marine invertebrates, how they vary across different life stages, and how these limits relate to environmental conditions. We tested the tolerance to acute heat stress of five life stages of the tropical sea urchin Lytechinus variegatus collected in the Bahía Almirante, Bocas del Toro, Panama. We also investigated the impact of chronic heat stress on larval development. Fertilization, cleavage, morula development, and 4-armed larvae tolerated 2-h exposures to elevated temperatures between 28-32°C. Average critical temperatures (LT 50) were lower for initiation of cleavage (33.5°C) and development to morula (32.5°C) than they were for fertilization (34.4°C) or for 4-armed larvae (34.1°C). LT 50 was even higher (34.8°C) for adults exposed to similar acute thermal stress, suggesting that thermal limits measured for adults may not be directly applied to the whole life history. During chronic exposure, larvae had significantly lower survival and reduced growth when reared at temperatures above 30.5°C and did not survive chronic exposures at or above 32.3°C. Environmental monitoring at and near our collection site shows that L. variegatus may already experience temperatures at which larval growth and survival are reduced during the warmest months of the year. A published local climate model further suggests that such damaging warm temperatures will be reached throughout the Bahía Almirante by 2084. Our results highlight that tropical marine invertebrates likely have small thermal safety factors during some stages in their life cycles, and that shallow-water populations are at particular risk of near future warming.

  12. The sea urchin Lytechinus variegatus lives close to the upper thermal limit for early development in a tropical lagoon.

    PubMed

    Collin, Rachel; Chan, Kit Yu Karen

    2016-08-01

    Thermal tolerance shapes organisms' physiological performance and limits their biogeographic ranges. Tropical terrestrial organisms are thought to live very near their upper thermal tolerance limits, and such small thermal safety factors put them at risk from global warming. However, little is known about the thermal tolerances of tropical marine invertebrates, how they vary across different life stages, and how these limits relate to environmental conditions. We tested the tolerance to acute heat stress of five life stages of the tropical sea urchin Lytechinus variegatus collected in the Bahía Almirante, Bocas del Toro, Panama. We also investigated the impact of chronic heat stress on larval development. Fertilization, cleavage, morula development, and 4-armed larvae tolerated 2-h exposures to elevated temperatures between 28-32°C. Average critical temperatures (LT 50) were lower for initiation of cleavage (33.5°C) and development to morula (32.5°C) than they were for fertilization (34.4°C) or for 4-armed larvae (34.1°C). LT 50 was even higher (34.8°C) for adults exposed to similar acute thermal stress, suggesting that thermal limits measured for adults may not be directly applied to the whole life history. During chronic exposure, larvae had significantly lower survival and reduced growth when reared at temperatures above 30.5°C and did not survive chronic exposures at or above 32.3°C. Environmental monitoring at and near our collection site shows that L. variegatus may already experience temperatures at which larval growth and survival are reduced during the warmest months of the year. A published local climate model further suggests that such damaging warm temperatures will be reached throughout the Bahía Almirante by 2084. Our results highlight that tropical marine invertebrates likely have small thermal safety factors during some stages in their life cycles, and that shallow-water populations are at particular risk of near future warming. PMID

  13. The upper and lower limits of the mechanistic stoichiometry of mitochondrial oxidative phosphorylation. Stoichiometry of oxidative phosphorylation.

    PubMed

    Beavis, A D; Lehninger, A L

    1986-07-15

    Determination of the intrinsic or mechanistic P/O ratio of oxidative phosphorylation is difficult because of the unknown magnitude of leak fluxes. Applying a new approach developed to overcome this problem (see our preceding paper in this journal), the relationships between the rate of O2 uptake [( Jo)3], the net rate of phosphorylation (Jp), the P/O ratio, and the respiratory control ratio (RCR) have been determined in rat liver mitochondria when the rate of phosphorylation was systematically varied by three specific means. (a) When phosphorylation is titrated with carboxyatractyloside, linear relationships are observed between Jp and (Jo)3. These data indicate that the upper limit of the mechanistic P/O ratio is 1.80 for succinate and 2.90 for 3-hydroxybutyrate oxidation. (b) Titration with malonate or antimycin yields linear relationships between Jp and (Jo)3. These data give the lower limit of the mechanistic P/O ratio of 1.63 for succinate and 2.66 for 3-hydroxybutyrate oxidation. (c) Titration with a protonophore yields linear relationships between Jp, (Jo)3, and (Jo)4 and between P/O and 1/RCR. Extrapolation of the P/O ratio to 1/RCR = 0 yields P/O ratios of 1.75 for succinate and 2.73 for 3-hydroxybutyrate oxidation which must be equal to or greater than the mechanistic stoichiometry. When published values for the H+/O and H+/ATP ejection ratios are taken into consideration, these measurements suggest that the mechanistic P/O ratio is 1.75 for succinate oxidation and 2.75 for NADH oxidation.

  14. The JAK2V617F tyrosine kinase mutation in blood donors with upper-limit haematocrit levels

    PubMed Central

    Tagariello, Giuseppe; Di Gaetano, Rosanna; Sartori, Roberto; Zanotto, Daniela; Belvini, Donata; Radossi, Paolo; Risato, Renzo; Roveroni, Giovanni; Salviato, Roberta; Tassinari, Cristina; Toffano, Nunzio

    2009-01-01

    Background It is not rare to observe in blood donors a level of haematocrit (Hct) above or close to the highest normal limit. In the case of blood donors the diagnosis and clinical evaluation of this alteration may be complicated by regular blood donations that can mask an underlying disease such as polycythaemia vera. Recently a single acquired mutation in the Janus kinase 2 gene (JAK2) on chromosome 9 was identified and it was found that the incidence of this mutation was high in patients with polycythaemia vera. Material and Methods From the January 1, 2006 to December 31, 2006 all consecutive donors with a Hct above 50% if males (n=84) and 46% if females (n=19) underwent JAK2 mutation analysis. Seventy-nine donors (59 males and 20 females) whose Hct was normal at their last blood donation were randomly selected and used as controls. Results Among the group of blood donors with a high Hct, we identified one donor who was positive for the JAK2 mutation. This man had a Hct of 50.6% at his last donation, while his average Hct in the preceding year was 51.7%. The prevalence of the JAK2 mutation could be estimated to be 1%, 0.6% or 0.02% in the three different populations considered: donors with a Hct level above the upper limit of normal, all tested donors or the entire donor cohort attending our transfusion service, respectively. Conclusions The present study suggests that apparently healthy subjects with repeatedly high levels of Hct may have the acquired mutation in JAK2. Laboratory screening tests for JAK2 may be offered to blood donors at transfusion services with expertise in molecular genetics. PMID:19503632

  15. Determination of absolute internal conversion coefficients using the SAGE spectrometer

    NASA Astrophysics Data System (ADS)

    Sorri, J.; Greenlees, P. T.; Papadakis, P.; Konki, J.; Cox, D. M.; Auranen, K.; Partanen, J.; Sandzelius, M.; Pakarinen, J.; Rahkila, P.; Uusitalo, J.; Herzberg, R.-D.; Smallcombe, J.; Davies, P. J.; Barton, C. J.; Jenkins, D. G.

    2016-03-01

    A non-reference based method to determine internal conversion coefficients using the SAGE spectrometer is carried out for transitions in the nuclei of 154Sm, 152Sm and 166Yb. The Normalised-Peak-to-Gamma method is in general an efficient tool to extract internal conversion coefficients. However, in many cases the required well-known reference transitions are not available. The data analysis steps required to determine absolute internal conversion coefficients with the SAGE spectrometer are presented. In addition, several background suppression methods are introduced and an example of how ancillary detectors can be used to select specific reaction products is given. The results obtained for ground-state band E2 transitions show that the absolute internal conversion coefficients can be extracted using the methods described with a reasonable accuracy. In some cases of less intense transitions only an upper limit for the internal conversion coefficient could be given.

  16. Absolute nuclear material assay

    DOEpatents

    Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.

    2012-05-15

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  17. Absolute nuclear material assay

    DOEpatents

    Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.

    2010-07-13

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  18. SENSITIVITY OF NORMAL THEORY METHODS TO MODEL MISSPECIFICATION IN THE CALCULATION OF UPPER CONFIDENCE LIMITS ON THE RISK FUNCTION FOR CONTINUOUS RESPONSES. (R825385)

    EPA Science Inventory

    Normal theory procedures for calculating upper confidence limits (UCL) on the risk function for continuous responses work well when the data come from a normal distribution. However, if the data come from an alternative distribution, the application of the normal theory procedure...

  19. Factors affecting the f × Q product of 3C-SiC microstrings: What is the upper limit for sensitivity?

    NASA Astrophysics Data System (ADS)

    Kermany, Atieh R.; Bennett, James S.; Brawley, George A.; Bowen, Warwick P.; Iacopi, Francesca

    2016-02-01

    The fn × Q (Hz) is a crucial sensitivity parameter for micro-electro-mechanical sensing. We have recently shown a fn × Q product of ˜1012 Hz for microstrings made of cubic silicon carbide on silicon, establishing a new state-of-the-art and opening new frontiers for mass sensing applications. In this work, we analyse the main parameters influencing the frequency and quality factor of silicon carbide microstrings (material properties, microstring geometry, clamping condition, and environmental pressure) and investigate the potential for approaching the theoretical upper limit. We indicate that our previous result is only about a factor 2 lower than the thermoelastic dissipation limit. For fully reaching this upper limit, a substantial reduction of the defects in the silicon carbide thin film would be required, while maintaining a high residual tensile stress in the perfect-clamped strings.

  20. Sediment Microbial Enzyme Activity as an Indicator of Nutrient Limitation in the Great Rivers of the Upper Mississippi Basin

    EPA Science Inventory

    We compared extracellular enzyme activity (EEA) of microbial assemblages in river sediments at 447 sites along the Upper Mississippi, Missouri, and Ohio Rivers with sediment and water chemistry, atmospheric deposition of nitrogen and sulfate, and catchment land uses. The sites re...

  1. Enhanced Transmural Fiber Rotation and Connexin 43 Heterogeneity Are Associated With an Increased Upper Limit of Vulnerability in a Transgenic Rabbit Model of Human Hypertrophic Cardiomyopathy

    PubMed Central

    Ripplinger, Crystal M.; Li, Wenwen; Hadley, Jennifer; Chen, Junjie; Rothenberg, Florence; Lombardi, Raffaella; Wickline, Samuel A.; Marian, Ali J.; Efimov, Igor R.

    2008-01-01

    Human hypertrophic cardiomyopathy, characterized by cardiac hypertrophy and myocyte disarray, is the most common cause of sudden cardiac death in the young. Hypertrophic cardiomyopathy is often caused by mutations in sarcomeric genes. We sought to determine arrhythmia propensity and underlying mechanisms contributing to arrhythmia in a transgenic (TG) rabbit model (β-myosin heavy chain–Q403) of human hypertrophic cardiomyopathy. Langendorff-perfused hearts from TG (n = 6) and wild-type (WT) rabbits (n = 6) were optically mapped. The upper and lower limits of vulnerability, action potential duration (APD) restitution, and conduction velocity were measured. The transmural fiber angle shift was determined using diffusion tensor MRI. The transmural distribution of connexin 43 was quantified with immunohistochemistry. The upper limit of vulnerability was significantly increased in TG versus WT hearts (13.3 ± 2.1 versus 7.4 ± 2.3 V/cm; P = 3.2e−5), whereas the lower limits of vulnerability were similar. APD restitution, conduction velocities, and anisotropy were also similar. Left ventricular transmural fiber rotation was significantly higher in TG versus WT hearts (95.6 ± 10.9° versus 79.2 ± 7.8°; P = 0.039). The connexin 43 density was significantly increased in the mid-myocardium of TG hearts compared with WT (5.46 ± 2.44% versus 2.68 ± 0.77%; P = 0.024), and similar densities were observed in the endo- and epicardium. Because a nearly 2-fold increase in upper limit of vulnerability was observed in the TG hearts without significant changes in APD restitution, conduction velocity, or the anisotropy ratio, we conclude that structural remodeling may underlie the elevated upper limit of vulnerability in human hypertrophic cardiomyopathy. PMID:17885214

  2. Limiter

    DOEpatents

    Cohen, S.A.; Hosea, J.C.; Timberlake, J.R.

    1984-10-19

    A limiter with a specially contoured front face is provided. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution. This limiter shape accommodates the various power scrape-off distances lambda p, which depend on the parallel velocity, V/sub parallel/, of the impacting particles.

  3. An upper limit for the rate coefficient of the reaction of NH2 radicals with O2 using FTIR product analysis

    NASA Technical Reports Server (NTRS)

    Tyndall, G. S.; Orlando, J. J.; Nickerson, Karen E.; Cantrell, C. A.; Calvert, J. G.

    1991-01-01

    Fourier transform infrared spectrometry has been used to study the products of the photooxidation of ammonia in the presence of oxygen at 296 K. The data have been used to derive an upper limit of 6 x 10 exp -21/cu cm molecule s for the reaction of NH2 radicals with O2 to produce NO(x) at 296 K. This upper limit, which is three orders of magnitude lower than previous estimates based on the kinetics of NH2 loss, rules out the importance of this reaction in the atmosphere and suggests that NH2 will be oxidized by O3 or NO2. The effect on the NO(x) and N2O budgets depends critically on the products of the NH2 + O3 reaction. Simulations of the experimental product yields also allow an evaluation of possible product channels for the reaction of NH2 with HO2.

  4. An upper limit of muon flux of energies above 100 TeV determined from horizontal air showers observed at Akeno

    NASA Technical Reports Server (NTRS)

    Nagano, M.; Yoshii, H.; Hara, T.; Kamata, K.; Kawaguchi, S.; Kifune, T.

    1985-01-01

    Muon energy spectrum above 100 TeV was determined by observing the extensive air showers (EAS) from the horizontal direction (HAS). No definite muon originated shower of sizes above 100,000 and zenith angles above 60 deg was observed. The upper limits of HAS intensity is 5x10/12 m/2 s/1 sn/1 above 100,000. It is indicated that the upper limit of muon flux above 100 TeV is about 1.3x10/8 m/2 s/1 sr/1 and is in agreement with that expected from the primary spectrum with a knee assuming scaling in the fragmentation region and 40% protons in the primary beam. The critical energy at which muon flux from prompt processes take over that from the conventional process is higher than 100 Tev at horizontal direction.

  5. Absolute biological needs.

    PubMed

    McLeod, Stephen

    2014-07-01

    Absolute needs (as against instrumental needs) are independent of the ends, goals and purposes of personal agents. Against the view that the only needs are instrumental needs, David Wiggins and Garrett Thomson have defended absolute needs on the grounds that the verb 'need' has instrumental and absolute senses. While remaining neutral about it, this article does not adopt that approach. Instead, it suggests that there are absolute biological needs. The absolute nature of these needs is defended by appeal to: their objectivity (as against mind-dependence); the universality of the phenomenon of needing across the plant and animal kingdoms; the impossibility that biological needs depend wholly upon the exercise of the abilities characteristic of personal agency; the contention that the possession of biological needs is prior to the possession of the abilities characteristic of personal agency. Finally, three philosophical usages of 'normative' are distinguished. On two of these, to describe a phenomenon or claim as 'normative' is to describe it as value-dependent. A description of a phenomenon or claim as 'normative' in the third sense does not entail such value-dependency, though it leaves open the possibility that value depends upon the phenomenon or upon the truth of the claim. It is argued that while survival needs (or claims about them) may well be normative in this third sense, they are normative in neither of the first two. Thus, the idea of absolute need is not inherently normative in either of the first two senses. PMID:23586876

  6. Absolute biological needs.

    PubMed

    McLeod, Stephen

    2014-07-01

    Absolute needs (as against instrumental needs) are independent of the ends, goals and purposes of personal agents. Against the view that the only needs are instrumental needs, David Wiggins and Garrett Thomson have defended absolute needs on the grounds that the verb 'need' has instrumental and absolute senses. While remaining neutral about it, this article does not adopt that approach. Instead, it suggests that there are absolute biological needs. The absolute nature of these needs is defended by appeal to: their objectivity (as against mind-dependence); the universality of the phenomenon of needing across the plant and animal kingdoms; the impossibility that biological needs depend wholly upon the exercise of the abilities characteristic of personal agency; the contention that the possession of biological needs is prior to the possession of the abilities characteristic of personal agency. Finally, three philosophical usages of 'normative' are distinguished. On two of these, to describe a phenomenon or claim as 'normative' is to describe it as value-dependent. A description of a phenomenon or claim as 'normative' in the third sense does not entail such value-dependency, though it leaves open the possibility that value depends upon the phenomenon or upon the truth of the claim. It is argued that while survival needs (or claims about them) may well be normative in this third sense, they are normative in neither of the first two. Thus, the idea of absolute need is not inherently normative in either of the first two senses.

  7. Sediment Microbial Enzyme Activity as an Indicator of Nutrient Limitation in the Great Rivers of the Upper Mississippi River Basin

    EPA Science Inventory

    Three conclusions are evident from our comparison of approaches for estimating nutrient limitation in these large floodplain rivers: 1) water chemistry and enzymes indicate that P-limitation is more prevalent than N-limitation; 2) the Ohio River reaches are more extensively P-lim...

  8. Limiter

    DOEpatents

    Cohen, Samuel A.; Hosea, Joel C.; Timberlake, John R.

    1986-01-01

    A limiter with a specially contoured front face accommodates the various power scrape-off distances .lambda..sub.p, which depend on the parallel velocity, V.sub..parallel., of the impacting particles. The front face of the limiter (the plasma-side face) is flat with a central indentation. In addition, the limiter shape is cylindrically symmetric so that the limiter can be rotated for greater heat distribution.

  9. U-Pb age of zircon crystals from the upper banner tonstein (Middle Pennsylvanian), Virginia: Absolute age of the Lower Pennsylvanian-Middle Pennsylvanian boundary and depositional rates for the Middle Pennsylvanian, central appalachian basin

    USGS Publications Warehouse

    Lyons, P.C.; Krogh, T.E.; Kwok, Y.Y.; Zodrow, E.L.

    1997-01-01

    The Upper Banner tonstein, a kaolinized volcanic ash bed that occurs about 90 m above the base of the Middle Pennsylvanian Series in Virginia, is the oldest known Middle Pennsylvanian tonstein in the Appalachian basin. On the basis of palynostratigraphy, the Upper Banner coal bed correlates approximately with the Langsettian-Duckmantian (ex Westphalian A-B) boundary in Europe. Stratigraphically, the Upper Banner tonstein occurs 440-480 m below the Fire Clay tonstein, which in turn is 25-50 m below the marine Magoffin Member of the Breathitt Formation, the approximate correlative of the Agir Marine Band that marks the Dunckmantian-Bolsovian (ex Westphalian C) boundary in Europe. Six single-crystal U-Pb zircon ages were determined for the Upper Banner tonstein. Of these, four overlap concordia within uncertainties and have 206Pb/238U ages that range from 306 to 310??1 Ma. Another analysis falls in the same group but plots slightly to the right of the curve, whereas a single analysis of a low uranium zircon grain gives an age of 316??1 Ma. Variation in ages is outside of analytical uncertainty; hence, variable amounts of recent Pb loss is implied, and the most probable (minimum) depositional age is given by the oldest value at 316??1 Ma - an age consistent with a mean sanidine 40Ar/39Ar plateau age of 311.2??0.7 Ma for the stratigraphically younger Fire Clay tonstein. Thus, the Upper Banner tonstein-Fire Clay tonstein interval is about 5 ?? 1 m.y. This period of time for the Dunckmantian Stage is in good agreement with the Hess and Lippolt (1986) and Hess et al. (1988) chronology for the Duckmantian based on 40Ar/39Ar plateau methods for Westphalian tonsteins. Also, on the basis of this period of time, calculated sedimentation rates (decompacted) od 66-165 m/m.y. were determined for the lower part of the Middle Pennsylvanian Series in the central Appalachian basin. These rates are consistent with the sedimentation rates for shallow-water marine siliciclastic sediments

  10. Simulation of upper-ocean biogeochemistry with a flexible-composition phytoplankton model: C, N and Si cycling and Fe limitation in the Southern Ocean

    NASA Astrophysics Data System (ADS)

    Mongin, Mathieu; Nelson, David M.; Pondaven, Philippe; Tréguer, Paul

    2006-03-01

    We previously reported the application of an upper-ocean biogeochemical model in which the elemental composition of the phytoplankton is flexible and responds to changes in light and nutrient availability [Mongin, M., Nelson, D., Pondaven, P., Brzezinski, M., Tréguer, P., 2003. Simulation of upper-ocean biogeochemistry with a flexible-composition phytoplankton model: C, N and Si cycling in the western Sargasso Sea. Deep-Sea Research I 50, 1445-1480]. That model, applied in the western Sargasso Sea, considered the cycles of C, N and Si in the upper 400 m and limitation of phytoplankton growth by N, Si and light. We now report a new version of this model that includes Fe cycling and Fe limitation and its application in the Southern Ocean. The model includes two phytoplankton groups, diatoms and non-siliceous forms. Uptake of NO 3- by phytoplankton is light dependent, but NH 4+, Si(OH) 4 and Fe uptake are not and can therefore continue through the night. The model tracks the resulting C/N and Fe/C ratios of both groups and Si/N ratio of diatoms, and permits uptake of C, N, Fe and Si to proceed independently when those ratios are close to those of nutrient-replete phytoplankton. When they indicate a deficiency cellular C, N, Fe or Si, uptake of the non-limiting elements is controlled by the content of the limiting element in accordance with the cell-quota formulation of [Droop, M., 1974. The nutrient status of algal cell in continuous culture. Journal of the Marine Biological Association of the United Kingdom 54, 825-855]. The model thus identifies the growth-limiting element and quantifies the degree of limitation from the elemental composition of the phytoplankton. We applied this model at the French KERFIX site in the Indian Ocean sector of the Southern Ocean, using meteorological forcing for that site from 1991 to 1995. As in the Sargasso Sea application, the flexible-composition structure provides simulations that are consistent with field data with only minimal

  11. The absolute path command

    2012-05-11

    The ap command traveres all symlinks in a given file, directory, or executable name to identify the final absolute path. It can print just the final path, each intermediate link along with the symlink chan, and the permissions and ownership of each directory component in the final path. It has functionality similar to "which", except that it shows the final path instead of the first path. It is also similar to "pwd", but it canmore » provide the absolute path to a relative directory from the current working directory.« less

  12. The absolute path command

    SciTech Connect

    Moody, A.

    2012-05-11

    The ap command traveres all symlinks in a given file, directory, or executable name to identify the final absolute path. It can print just the final path, each intermediate link along with the symlink chan, and the permissions and ownership of each directory component in the final path. It has functionality similar to "which", except that it shows the final path instead of the first path. It is also similar to "pwd", but it can provide the absolute path to a relative directory from the current working directory.

  13. K band SINFONI spectra of two z ~ 5 submillimeter galaxy systems: upper limits to the unobscured star formation from [O II] optical emission line searches

    NASA Astrophysics Data System (ADS)

    Couto, Guilherme S.; Colina, Luis; López, Javier Piqueras; Storchi-Bergmann, Thaisa; Arribas, Santiago

    2016-10-01

    We present deep SINFONI K-band integral field spectra of two submillimeter galaxy systems (SMG): BR 1202-0725 and J1000+0234, at z = 4.69 and 4.55, respectively. Spectra extracted for each object in the two systems do not show any signature of the [O ii]λλ3726, 29 Å emission-lines, placing upper flux limits of 3.9 and 2.5 × 10-18erg s-1 cm-2for BR 1202-0725 and J1000+0234, respectively. Using the relation between the star formation rate (SFR) and the luminosity of the [O ii] doublet, we estimate unobscured SFR upper limits of ~ 10-15 M⊙ yr-1and ~30-40 M⊙ yr-1for the objects of the two systems, respectively. For the SMGs, these values are at least two orders of magnitude lower than those derived from SED and IR luminosities. The differences on the SFR values would correspond to internal extinction of, at least, 3.4-4.9 and 2.1-3.6 mag in the visual for BR 1202-0725 and J1000+0234 SMGs, respectively. The upper limit for the [O ii]-derived SFR in one of the LAEs (Lyα2) in the BR1202-0725 system is at least one order of magnitude lower than the previous SFR derived from infrared tracers, while both estimates are in good agreement for Lyα1. The lower limits to the internal extinction in these two Lyman-alpha emitters are 0.6 mag and 1.3 mag, respectively. No evidence for [O ii] emission associated with Lyα1 is identified in our data, implying that residuals of the K-band sky emission lines after subtraction in medium-band imaging data could provide the adequate flux.

  14. Upper Limits on the Masses of 105 Supermassive Black Holes from Hubble Space Telescope/Space Telescope Imaging Spectrograph Archival Data

    NASA Astrophysics Data System (ADS)

    Beifiori, A.; Sarzi, M.; Corsini, E. M.; Dalla Bontà, E.; Pizzella, A.; Coccato, L.; Bertola, F.

    2009-02-01

    Based on the modeling of the central emission-line width measured over subarcsecond apertures with the Hubble Space Telescope, we present stringent upper bounds on the mass of the central supermassive black hole, M •, for a sample of 105 nearby galaxies (D < 100 Mpc) spanning a wide range of Hubble types (E-Sc) and values of the central stellar velocity dispersion, σc (58-419 km s-1). For the vast majority of the objects, the derived M • upper limits run parallel and above the well-known M •-σc relation independently of the galaxy distance, suggesting that our nebular line-width measurements trace rather well the nuclear gravitational potential. For values of σc between 90 and 220 km s-1, 68% of our upper limits falls immediately above the M •-σc relation without exceeding the expected M • values by more than a factor 4.1. No systematic trends or offsets are observed in this σc range as a function of the galaxy Hubble type or with respect to the presence of a bar. For 6 of our 12 M • upper limits with σc <90 km s-1, our line-width measurements are more sensitive to the stellar contribution to the gravitational potential, either due to the presence of a nuclear stellar cluster or because of a greater distance compared to the other galaxies at the low-σc end of the M •-σc relation. Conversely, our M • upper bounds appear to lie closer to the expected M • in the most massive elliptical galaxies with values of σc above 220 km s-1. Such a flattening of the M •-σc relation at its high-σc end would appear consistent with a coevolution of supermassive black holes and galaxies driven by dry mergers, although better and more consistent measurements for σc and K-band luminosity are needed for these kinds of objects before systematic effects can be ruled out. Based on observations with the NASA/ESA Hubble Space Telescope obtained at STScI, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA

  15. A simple temperature-based model predicts the upper latitudinal limit of the temperate coral Astrangia poculata

    NASA Astrophysics Data System (ADS)

    Dimond, J. L.; Kerwin, A. H.; Rotjan, R.; Sharp, K.; Stewart, F. J.; Thornhill, D. J.

    2013-06-01

    A few hardy ahermatypic scleractinian corals occur in shallow waters well outside of the tropics, but little is known concerning their distribution limits at high latitudes. Using field data on the growth of Astrangia poculata over an annual period near its northern range limit in Rhode Island, USA, we tested the hypothesis that the distribution of this coral is limited by low temperature. A simple model based on satellite sea surface temperature and field growth data at monthly temporal resolution was used to estimate annual net coral growth north and south of the known range limit of A. poculata. Annual net coral growth was the result of new polyp budding above ~10 °C minus polyp loss below ~10 °C, which is caused by a state of torpor that leads to overgrowth by encroaching and settling organisms. The model accurately predicted A. poculata's range limit around Cape Cod, Massachusetts, predicting no net growth northward as a result of corals' inability to counteract polyp loss during winter with sufficient polyp budding during summer. The model also indicated that the range limit of A. poculata coincides with a decline in the benefit of associating with symbiotic dinoflagellates ( Symbiodinium B2/ S. psygmophilum), suggesting that symbiosis may become a liability under colder temperatures. While we cannot exclude the potential role of other coral life history traits or environmental factors in setting A. poculata's northern range limit, our analysis suggests that low temperature constrains the growth and persistence of adult corals and would preclude coral growth northward of Cape Cod.

  16. Combined CDF and D0 Upper Limits on Standard Model Higgs-Boson Production with 2.1 - 5.4 fb-1 of Data

    SciTech Connect

    Collaboration, The CDF; Collaboration, the D0; Physics, the Tevatron New; Group, Higgs Working

    2009-11-01

    We combine results from CDF and D0 on direct searches for a standard model (SM) Higgs boson (H) in p{bar p} collisions at the Fermilab Tevatron at {radical}s = 1.96 TeV. Compared to the previous Tevatron Higgs search combination more data have been added and some previously used channels have been reanalyzed to gain sensitivity. We use the latest parton distribution functions and gg {yields} H theoretical cross sections when comparing our limits to the SM predictions. With 2.0-4.8 fb{sup -1} of data analyzed at CDF, and 2.1-5.4 fb{sup -1} at D0, the 95% C.L. upper limits on Higgs boson production are a factor of 2.70 (0.94) times the SM cross section for a Higgs boson mass of m{sub H} = 115 (165) GeV/c{sup 2}. The corresponding median upper limits expected in the absence of Higgs boson production are 1.78 (0.89). The mass range excluded at 95% C.L. for a SM Higgs is 163 < m{sub H} < 166 GeV/c{sup 2}, with an expected exclusion of 159 < m{sub H} < 168 GeV/c{sup 2}.

  17. Pushing the upper limit of Rayleigh-scatter Temperatures Retrievals into the Lower Thermosphere Using an Inversion Approach

    NASA Astrophysics Data System (ADS)

    Bandoro, J.; Sica, R. J.; Argall, S.

    2012-12-01

    An important aspect of solar terrestrial relations is the coupling between the lower and upper atmosphere-ionosphere system. The coupling is evident in the general circulation of the atmosphere, where waves generate in the lower atmosphere play an important role in the dynamics of the upper atmosphere, which feeds back on the lower atmosphere's circulation. To address coupling problems requires measurements over the broadest range of heights possible. A recently developed retrieval method for temperature profiles from Rayleigh-scatter lidar measurements using an inversion approach allows the upward extension of the altitude range of temperature by 10 to 15 km over the conventional method, thus producing the equivalent of increasing the systems power-aperture product by 4 times [1]. The method requires no changes to the lidar's hardware and thus, can be applied to the body of existing measurements. In addition, since the uncertainties of the retrieved temperature profile are found by a Monte Carlo error analysis, it is possible to isolate systematic and random uncertainties to model the effect of each one on the final uncertainty product for the temperature profile. This unambiguous separation of uncertainties was not previously possible as only the propagation of the statistical uncertainties are typically reported. For the Purple Crow Lidar, corrections for saturation (e.g. non-linearity) in the photocount returns, ozone extinction and background removal all contribute to the overall systematic uncertainty. Results of individually varying each systematic correction and the effect on the final temperature uncertainty through Monte Carlo realizations are presented to determine the importance for each one. For example, it was found that treatment of the background correction as a systematic versus statistical uncertainty gave results in agreement with each other. This new method is then applied to measurements obtained by the Purple Crow lidar' Rayleigh

  18. Increasing Capacity: Practice Effects in Absolute Identification

    ERIC Educational Resources Information Center

    Dodds, Pennie; Donkin, Christopher; Brown, Scott D.; Heathcote, Andrew

    2011-01-01

    In most of the long history of the study of absolute identification--since Miller's (1956) seminal article--a severe limit on performance has been observed, and this limit has resisted improvement even by extensive practice. In a startling result, Rouder, Morey, Cowan, and Pfaltz (2004) found substantially improved performance with practice in the…

  19. Measurement of the {tau} Lepton Mass and an Upper Limit on the Mass Difference between {tau}{sup +} and {tau}{sup -}

    SciTech Connect

    Belous, K.; Shapkin, M.; Sokolov, A.; Abe, K.; Adachi, I.; Gershon, T.; Haba, J.; Hazumi, M.; Itoh, R.; Iwasaki, Y.; Katayama, N.; Kichimi, H.; Krokovny, P.; Nakao, M.; Nakazawa, H.; Nishida, S.; Ozaki, H.; Sakai, Y.; Suzuki, S. Y.; Takasaki, F.

    2007-07-06

    The mass of the {tau} lepton has been measured in the decay mode {tau}{yields}3{pi}{nu}{sub {tau}} using a pseudomass technique. The result obtained from 414 fb{sup -1} of data collected with the Belle detector is M{sub {tau}}=[1776.61{+-}0.13(stat){+-}0.35(sys)] MeV/c{sup 2}. The upper limit on the relative mass difference between positive and negative {tau} leptons is vertical bar M{sub {tau}{sup +}}-M{sub {tau}{sup -}} vertical bar/M{sub {tau}}<2.8x10{sup -4} at 90% confidence level.

  20. Upper Limits of Stratsopsheric Io and Oio Inferred From Center-to-limb Darkening Corrected Balloon Borne Solar Occultation Spectra: Implication For Total Gaseous Iodine and Stratsopsheric Ozone

    NASA Astrophysics Data System (ADS)

    Boesch, H.; Camy Peyret, C.; Dorf, M.; Fitzenberger, R.; Platt, U.; Weidner, F.; Pfeilsticker, K.

    We report upper limits of lower stratospheric IO (0.055+/-0.004) ppt and OIO (0.056+/-0.003) ppt inferred from balloon-borne solar occultation UV/visible spec- troscopy (<20 km). The spectra were recorded during a series of LPMA/DOAS (Labo- ratoire de Physique Moléculaire et Applications/Differential Optical Absorption Spec- troscopy) balloon flights that were conducted at different geophysical conditions i.e., inside the arctic winter vortex, at mid-, and high latitudes in spring, summer, and fall. Photochemical modeling that accounts for the iodine partitioning

  1. Upper limits for stereoselective photodissociation of free amino acids in the vacuum ultraviolet region and at the C 1s edge

    SciTech Connect

    Pruemper, Georg; Viefhaus, Jens; Cvejanovic, Slobodan; Rolles, Daniel; Gessner, Oliver; Lischke, Toralf; Hentges, Rainer; Wienberg, Christian; Mahler, Willy; Becker, Uwe; Langer, Burkhard; Prosperi, Tommaso; Zema, Nicola; Turchini, Stefano; Zada, Birgitt; Senf, Fred

    2004-06-01

    We measured the total and partial ion yields of the two chiral amino acids alanine and serine in the gas phase both in the vacuum ultraviolet region and at the C(1s) edge using circularly polarized light. We did not detect any circular dichroism asymmetry larger than 1x10{sup -3}. A similar measurement of fixed-in-space amino acids yielded an upper limit of 1x10{sup -2} for the stereoselective effect of circularly polarized light. The results obtained are relevant for quantitative models of stereoselective photodecomposition of amino acids that try to explain the homochirality of life.

  2. Pauli-limited Upper Critical Field of Fe1+yTe1−xSex

    SciTech Connect

    Petrovic, C.; Lei, H.; Hu, R.; Choi, E.S.; Warren, J.B.

    2010-01-11

    In this work, we investigated the temperature dependence of the upper critical field {mu}{sub 0}H{sub c2}(T) of Fe1.02(3)Te0.61(4)Se0.39(4) and Fe1.05(3)Te0.89(2)Se0.11(2) single crystals by measuring the magnetotransport properties in stable dc magnetic fields up to 35 T. Both crystals show that {mu}{sub 0}H{sub c2}(T) in the ab plane and along the c-axis exhibit saturation at low temperatures. The anisotropy of {mu}{sub 0}H{sub c2}(T) decreases with decreasing temperature, becoming nearly isotropic when the temperature T {yields} 0. Furthermore, {mu}{sub 0}H{sub c2}(0) deviates from the conventional Werthamer-Helfand-Hohenberg theoretical prediction values for both field directions. Our analysis indicates that the spin-paramagnetic pair-breaking effect is responsible for the temperature-dependent behavior of {mu}{sub 0}H{sub c2}(T) in both field directions.

  3. Changing Land Use to Offset CO2 Emissions: Limited Potential for the Upper Midwest of the U.S.

    NASA Astrophysics Data System (ADS)

    Fissore, C.; Espelata, J. F.; Nater, E. A.; Hobbie, S. E.; Reich, P. B.

    2008-12-01

    Efforts to mitigate increasing carbon (C) emissions are needed, and increasingly more policies point at terrestrial ecosystems as places to sequester atmospheric CO2. Whether terrestrial C sequestration can offset significant CO2 emissions is questionable, particularly in light of (1) increasing pressures on land use from an array of competing sectors including food and biofuel production and urbanization, and (2) a growing concern among scientists that previously published rates of C sequestration attributed to the conversion from conventional tillage to no-till or conservation tillage were overly optimistic. We analyzed the potential to promote terrestrial C sequestration through changes in land use and land cover in the Upper Midwest of the U.S. over a 50-year timeframe based on available data. Although some land use and cover changes, such as restoring forests, grasslands and wetlands, cause substantial carbon storage for a given area of land, conversion of even 10% of the regions agricultural land would offset only a few percent of its carbon emissions. Conversion to no-till agricultural, although popular among policymakers, results in variable and, on average, negligible C sequestration (sequestration rates range from -0.2 to 0.8 Mg C ha-1 y-1). Despite the unquestionable ecological benefits of some of the proposed land use changes, land use change realistically can be only a modest part of a more comprehensive strategy to achieve significant emissions reductions.

  4. Measurements of the absolute branching fractions of B+/- --> K+/-X(cc).

    PubMed

    Aubert, B; Barate, R; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Pappagallo, M; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Chevalier, N; Cottingham, W N; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Teodorescu, L; Blinov, A E; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Weinstein, A J R; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Minamora, J S; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Andreassen, R; Mancinelli, G; Meadows, B T; Sokoloff, M D; Blanc, F; Bloom, P; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q; Altenburg, D; Feltresi, E; Hauke, A; Spaan, B; Brandt, T; Brose, J; Dickopp, M; Klose, V; Lacker, H M; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Bernard, D; Bonneaud, G R; Grenier, P; Schrenk, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Won, E; Wu, J; Dubitzky, R S; Langenegger, U; Marks, J; Schenk, S; Uwer, U; Schott, G; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Gaillard, J R; Nash, J A; Nikolich, M B; Vazquez, W Panduro; Chai, X; Charles, M J; Mader, W F; Mallik, U; Mohapatra, A K; Ziegler, V; Cochran, J; Crawley, H B; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Yi, J; Arnaud, N; Davier, M; Giroux, X; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Petersen, T C; Plaszczynski, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Parry, R J; Payne, D J; Schofield, K C; Touramanis, C; Cormack, C M; Di Lodovico, F; Menges, W; Sacco, R; Brown, C L; Cowan, G; Flaecher, H U; Green, M G; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Edgar, C L; Hodgkinson, M C; Kelly, M P; Lafferty, G D; Naisbit, M T; Williams, J C; Chen, C; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Kofler, R; Koptchev, V B; Li, X; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Koeneke, K; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Viaud, B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Snoek, H L; Wilden, L; Jessop, C P; Losecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Brau, J; Frey, R; Igonkina, O; Lu, M; Potter, C T; Sinev, N B; Strom, D; Strube, J; Torrence, E; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; John, M J J; Leruste, Ph; Malclès, J; Ocariz, J; Roos, L; Therin, G; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Biasini, M; Covarelli, R; Pacetti, S; Pioppi, M; Angelini, C; Batignani, G; Bettarini, S; Bucci, F; Calderini, G; Carpinelli, M; Cenci, R; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Walsh, J; Haire, M; Judd, D; Wagoner, D E; Biesiada, J; Danielson, N; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; Marco, E Di; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Gioi, L Li; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Tehrani, F Safai; Voena, C; Schröder, H; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B; Gopal, G P; Olaiya, E O; Wilson, F F; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Graziani, G; de Monchenault, G Hamel; Kozanecki, W; Legendre, M; London, G W; Mayer, B; Vasseur, G; Yèche, Ch; Zito, M; Purohit, M V; Weidemann, A W; Wilson, J R; Yumiceva, F X; Abe, T; Allen, M T; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmueller, O L; Claus, R; Coleman, J P; Convery, M R; Cristinziani, M; Dingfelder, J C; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W; Fan, S; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hast, C; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; van Bakel, N; Weaver, M; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Roat, C; Ahmed, M; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Saeed, M A; Wappler, F R; Zain, S B; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bona, M; Gallo, F; Gamba, D; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Vitale, L; Martinez-Vidal, F; Panvini, R S; Banerjee, Sw; Bhuyan, B; Brown, C M; Fortin, D; Hamano, K; Kowalewski, R; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Eichenbaum, A M; Flood, K T; Graham, M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Mellado, B; Mihalyi, A; Pan, Y; Pierini, M; Prepost, R; Tan, P; Wu, S L; Yu, Z; Neal, H

    2006-02-10

    We study the two-body decays of B+/- mesons to K+/- and a charmonium state X(cc) in a sample of 210.5 fb(-1) of data from the BABAR experiment. We perform measurements of absolute branching fractions beta(B+/- --> K+/-X(cc)) using a missing mass technique, and report several new or improved results. In particular, the upper limit beta(B+/- --> K+/- X(3872)) < 3.2 x 10(-4) at 90% C.L. and the inferred lower limit beta(X(3872)J/psipi+ pi-) > 4.2% will help in understanding the nature of the recently discovered X(3872).

  5. Pursuing the planet-debris disk connection: Analysis of upper limits from the Anglo-Australian planet search

    SciTech Connect

    Wittenmyer, Robert A.; Marshall, Jonathan P.

    2015-02-01

    Solid material in protoplanetary disks will suffer one of two fates after the epoch of planet formation; either being bound up into planetary bodies, or remaining in smaller planetesimals to be ground into dust. These end states are identified through detection of sub-stellar companions by periodic radial velocity (or transit) variations of the star, and excess emission at mid- and far-infrared wavelengths, respectively. Since the material that goes into producing the observable outcomes of planet formation is the same, we might expect these components to be related both to each other and their host star. Heretofore, our knowledge of planetary systems around other stars has been strongly limited by instrumental sensitivity. In this work, we combine observations at far-infrared wavelengths by IRAS, Spitzer, and Herschel with limits on planetary companions derived from non-detections in the 16 year Anglo-Australian Planet Search to clarify the architectures of these (potential) planetary systems and search for evidence of correlations between their constituent parts. We find no convincing evidence of such correlations, possibly owing to the dynamical history of the disk systems, or the greater distance of the planet-search targets. Our results place robust limits on the presence of Jupiter analogs which, in concert with the debris disk observations, provides insights on the small-body dynamics of these nearby systems.

  6. Middle Pleistocene Climate Change Recorded in Fossil Mammal Teeth from Tarija, Bolivia, and Upper Limit of the Ensenadan Land-Mammal Age

    NASA Astrophysics Data System (ADS)

    MacFadden, Bruce J.

    2000-07-01

    Fossiliferous middle Pleistocene sediments of the Tarija basin of southern Bolivia contain a classic Ensenadan land-mammal fauna. New carbon isotopic data reported here for 50 specimens of the grazing mammals Equus (horse) and Cuvieronius (mastodon), documented from eight stratigraphic levels at Tarija, vary significantly in the δ13C values of their teeth. The pattern of variation appears to reflect the proportion of C3 and C4 grasses eaten during colder (more C3) and warmer (more C4) times. Within age limits set by associated magnetostratigraphy, the cold periods can be correlated with particular even-numbered stages in the marine oxygen-isotope record, and the warm periods can be correlated with odd-numbered stages. The oldest fossil teeth analyzed from the Tarija section can thereby be assigned to stage 29, and the youngest to stages 17 or 15, that is; the teeth range in age from about 1.1 myr to as young as 0.7 myr. Based on correlation of the upper part of the Tarija beds to the isotopic stages, the upper limit of the Ensenadan land-mammal age is between 0.7 and 0.6 myr, which is younger than stated in most previous studies.

  7. Upper limit on the cross section for elastic neutralino-nucleon scattering in a neutrino experiment at the Baksan Underground Scintillator Telescope

    SciTech Connect

    Suvorova, O. V. Boliev, M. M. Demidov, S. V. Mikheyev, S. P.

    2013-11-15

    The results of a neutrino experiment that involved 24.12 yr of live time of observation of muons from the lower Earth's hemisphere with the aid of the Baksan Underground Scintillator Telescope are presented. In the problem of searches for a signal from the annihilation of dark matter in the Sun, an upper limit on the cross section for the elastic scattering of a weakly interacting massive particle (WIMP) on a nucleon was obtained at a 90% confidence level from an analysis of data accumulated within 21.15 yr of live time of observation. A neutralino in a nonminimal supersymmetric theory was considered for a WIMP. The best limit at the Baksan Underground Scintillator Telescope on the cross section for spin-dependent neutralino interactionwith a proton corresponds to 3 Multiplication-Sign 10{sup -4} pb for the neutralino mass of 210 GeV/c{sup 2}. This limit is three orders of magnitude more stringent than similar limits obtained in experiments that detected directly WIMP scattering on target nuclei.

  8. Combined CDF and D0 Upper Limits on Standard Model Higgs Boson Production with up to 8.6 fb-1 of Data

    SciTech Connect

    CDF, The; Collaborations, D0; Phenomena, the Tevatron New; Group, Higgs Working

    2011-07-01

    We combine results from CDF and D0 on direct searches for the standard model (SM) Higgs boson (H) in p{bar p} collisions at the Fermilab Tevatron at {radical}s = 1.96 TeV. Compared to the previous Tevatron Higgs boson search combination more data have been added, additional channels have been incorporated, and some previously used channels have been reanalyzed to gain sensitivity. We use the MSTW08 parton distribution functions and the latest theoretical cross sections when comparing our limits to the SM predictions. With up to 8.2 fb{sup -1} of data analyzed at CDF and up to 8.6 fb{sup -1} at D0, the 95% C.L. our upper limits on Higgs boson production are factors of 1.17, 1.71, and 0.48 times the values of the SM cross section for Higgs bosons of mass m{sub H} = 115 GeV/c{sup 2}, 140 GeV/c{sup 2}, and 165 GeV/c{sup 2}, respectively. The corresponding median upper limits expected in the absence of Higgs boson production are 1.16, 1.16, and 0.57. There is a small ({approx} 1{sigma}) excess of data events with respect to the background estimation in searches for the Higgs boson in the mass range 125 < m{sub H} < 155 GeV/c{sup 2}. We exclude, at the 95% C.L., a new and larger region at high mass between 156 < m{sub H} < 177 GeV/c{sup 2}, with an expected exclusion region of 148 < m{sub H} < 180 GeV/c{sup 2}.

  9. Nearing the cold-arid limits of microbial life in permafrost of an upper dry valley, Antarctica.

    PubMed

    Goordial, Jacqueline; Davila, Alfonso; Lacelle, Denis; Pollard, Wayne; Marinova, Margarita M; Greer, Charles W; DiRuggiero, Jocelyn; McKay, Christopher P; Whyte, Lyle G

    2016-07-01

    Some of the coldest and driest permafrost soils on Earth are located in the high-elevation McMurdo Dry Valleys (MDVs) of Antarctica, but little is known about the permafrost microbial communities other than that microorganisms are present in these valleys. Here, we describe the microbiology and habitable conditions of highly unique dry and ice-cemented permafrost in University Valley, one of the coldest and driest regions in the MDVs (1700 m above sea level; mean temperature -23 °C; no degree days above freezing), where the ice in permafrost originates from vapour deposition rather than liquid water. We found that culturable and total microbial biomass in University Valley was extremely low, and microbial activity under ambient conditions was undetectable. Our results contrast with reports from the lower-elevation Dry Valleys and Arctic permafrost soils where active microbial populations are found, suggesting that the combination of severe cold, aridity, oligotrophy of University Valley permafrost soils severely limit microbial activity and survival. PMID:27323892

  10. Nearing the cold-arid limits of microbial life in permafrost of an upper dry valley, Antarctica

    PubMed Central

    Goordial, Jacqueline; Davila, Alfonso; Lacelle, Denis; Pollard, Wayne; Marinova, Margarita M; Greer, Charles W; DiRuggiero, Jocelyn; McKay, Christopher P; Whyte, Lyle G

    2016-01-01

    Some of the coldest and driest permafrost soils on Earth are located in the high-elevation McMurdo Dry Valleys (MDVs) of Antarctica, but little is known about the permafrost microbial communities other than that microorganisms are present in these valleys. Here, we describe the microbiology and habitable conditions of highly unique dry and ice-cemented permafrost in University Valley, one of the coldest and driest regions in the MDVs (1700 m above sea level; mean temperature −23 °C; no degree days above freezing), where the ice in permafrost originates from vapour deposition rather than liquid water. We found that culturable and total microbial biomass in University Valley was extremely low, and microbial activity under ambient conditions was undetectable. Our results contrast with reports from the lower-elevation Dry Valleys and Arctic permafrost soils where active microbial populations are found, suggesting that the combination of severe cold, aridity, oligotrophy of University Valley permafrost soils severely limit microbial activity and survival. PMID:27323892

  11. SU-F-BRE-01: A Rapid Method to Determine An Upper Limit On a Radiation Detector's Correction Factor During the QA of IMRT Plans

    SciTech Connect

    Kamio, Y; Bouchard, H

    2014-06-15

    Purpose: Discrepancies in the verification of the absorbed dose to water from an IMRT plan using a radiation dosimeter can be wither caused by 1) detector specific nonstandard field correction factors as described by the formalism of Alfonso et al. 2) inaccurate delivery of the DQA plan. The aim of this work is to develop a simple/fast method to determine an upper limit on the contribution of composite field correction factors to these discrepancies. Methods: Indices that characterize the non-flatness of the symmetrised collapsed delivery (VSC) of IMRT fields over detector-specific regions of interest were shown to be correlated with IMRT field correction factors. The indices introduced are the uniformity index (UI) and the mean fluctuation index (MF). Each one of these correlation plots have 10 000 fields generated with a stochastic model. A total of eight radiation detectors were investigated in the radial orientation. An upper bound on the correction factors was evaluated by fitting values of high correction factors for a given index value. Results: These fitted curves can be used to compare the performance of radiation dosimeters in composite IMRT fields. Highly water-equivalent dosimeters like the scintillating detector (Exradin W1) and a generic alanine detector have been found to have corrections under 1% over a broad range of field modulations (0 – 0.12 for MF and 0 – 0.5 for UI). Other detectors have been shown to have corrections of a few percent over this range. Finally, a full Monte Carlo simulations of 18 clinical and nonclinical IMRT field showed good agreement with the fitted curve for the A12 ionization chamber. Conclusion: This work proposes a rapid method to evaluate an upper bound on the contribution of correction factors to discrepancies found in the verification of DQA plans.

  12. Core functional traits of bacterial communities in the Upper Mississippi River show limited variation in response to land cover

    PubMed Central

    Staley, Christopher; Gould, Trevor J.; Wang, Ping; Phillips, Jane; Cotner, James B.; Sadowsky, Michael J.

    2014-01-01

    Taxonomic characterization of environmental microbial communities via high-throughput DNA sequencing has revealed that patterns in microbial biogeography affect community structure. However, shifts in functional diversity related to variation in taxonomic composition are poorly understood. To overcome limitations due to the prohibitive cost of high-depth metagenomic sequencing, tools to infer functional diversity based on phylogenetic distributions of functional traits have been developed. In this study we characterized functional microbial diversity at 11 sites along the Mississippi River in Minnesota using both metagenomic sequencing and functional-inference-based (PICRUSt) approaches. This allowed us to determine how distance and variation in land cover throughout the river influenced the distribution of functional traits, as well as to validate PICRUSt inferences. The distribution and abundance of functional traits, by metagenomic analysis, were similar among sites, with a median standard deviation of 0.0002% among tier 3 functions in KEGG. Overall inferred functional variation was significantly different (P ≤ 0.035) between two water basins surrounded by agricultural vs. developed land cover, and abundances of bacterial orders that correlated with functional traits by metagenomic analysis were greater where abundances of the trait were inferred to be higher. PICRUSt inferences were significantly correlated (r = 0.147, P = 1.80 × 10−30) with metagenomic annotations. Discrepancies between metagenomic and PICRUSt taxonomic-functional relationships, however, suggested potential functional redundancy among abundant and rare taxa that impeded the ability to accurately assess unique functional traits among rare taxa at this sequencing depth. Results of this study suggest that a suite of “core functional traits” is conserved throughout the river and distributions of functional traits, rather than specific taxa, may shift in response to environmental

  13. Core functional traits of bacterial communities in the Upper Mississippi River show limited variation in response to land cover.

    PubMed

    Staley, Christopher; Gould, Trevor J; Wang, Ping; Phillips, Jane; Cotner, James B; Sadowsky, Michael J

    2014-01-01

    Taxonomic characterization of environmental microbial communities via high-throughput DNA sequencing has revealed that patterns in microbial biogeography affect community structure. However, shifts in functional diversity related to variation in taxonomic composition are poorly understood. To overcome limitations due to the prohibitive cost of high-depth metagenomic sequencing, tools to infer functional diversity based on phylogenetic distributions of functional traits have been developed. In this study we characterized functional microbial diversity at 11 sites along the Mississippi River in Minnesota using both metagenomic sequencing and functional-inference-based (PICRUSt) approaches. This allowed us to determine how distance and variation in land cover throughout the river influenced the distribution of functional traits, as well as to validate PICRUSt inferences. The distribution and abundance of functional traits, by metagenomic analysis, were similar among sites, with a median standard deviation of 0.0002% among tier 3 functions in KEGG. Overall inferred functional variation was significantly different (P ≤ 0.035) between two water basins surrounded by agricultural vs. developed land cover, and abundances of bacterial orders that correlated with functional traits by metagenomic analysis were greater where abundances of the trait were inferred to be higher. PICRUSt inferences were significantly correlated (r = 0.147, P = 1.80 × 10(-30)) with metagenomic annotations. Discrepancies between metagenomic and PICRUSt taxonomic-functional relationships, however, suggested potential functional redundancy among abundant and rare taxa that impeded the ability to accurately assess unique functional traits among rare taxa at this sequencing depth. Results of this study suggest that a suite of "core functional traits" is conserved throughout the river and distributions of functional traits, rather than specific taxa, may shift in response to environmental heterogeneity.

  14. ABSOLUTE POLARIMETRY AT RHIC.

    SciTech Connect

    OKADA; BRAVAR, A.; BUNCE, G.; GILL, R.; HUANG, H.; MAKDISI, Y.; NASS, A.; WOOD, J.; ZELENSKI, Z.; ET AL.

    2007-09-10

    Precise and absolute beam polarization measurements are critical for the RHIC spin physics program. Because all experimental spin-dependent results are normalized by beam polarization, the normalization uncertainty contributes directly to final physics uncertainties. We aimed to perform the beam polarization measurement to an accuracy Of {Delta}P{sub beam}/P{sub beam} < 5%. The absolute polarimeter consists of Polarized Atomic Hydrogen Gas Jet Target and left-right pairs of silicon strip detectors and was installed in the RHIC-ring in 2004. This system features proton-proton elastic scattering in the Coulomb nuclear interference (CNI) region. Precise measurements of the analyzing power A{sub N} of this process has allowed us to achieve {Delta}P{sub beam}/P{sub beam} = 4.2% in 2005 for the first long spin-physics run. In this report, we describe the entire set up and performance of the system. The procedure of beam polarization measurement and analysis results from 2004-2005 are described. Physics topics of AN in the CNI region (four-momentum transfer squared 0.001 < -t < 0.032 (GeV/c){sup 2}) are also discussed. We point out the current issues and expected optimum accuracy in 2006 and the future.

  15. Towards Determining the Upper Temperature Limits to Life on Earth: An In-situ Sulfide-Microbial Incubator

    NASA Astrophysics Data System (ADS)

    Kelley, D.; Baross, J.; Delaney, J.; Girguis, P.; Schrenk, M.

    2004-12-01

    Determining the maximum conditions under which life thrives, survives, and expires is critical to understanding how and where life might have evolved on our planet and for investigation of life in extraterrestrial environments. Submarine black smoker systems are optimal sites to study such questions because thermal gradients are extreme and accessible within the chimney walls under high-pressure conditions. Intact cells containing DNA and ribosomes have been observed even within the most extreme environments of sulfide structure walls bounded by 300\\deg C fluids. Membrane lipids from archaea have been detected in sulfide flanges and chimneys where temperatures are believed to be 200-300\\deg C. However, a balanced inquiry into the limits of life must focus on characterization of the actual conditions in a given system that favor reactions necessary to initiate and/or sustain life. At present, in-situ instrumentation of sulfide deposits is the only effective way to gain direct access to these natural high-temperature environments for documentation and experimentation. With this goal in mind, three prototype microbial incubators were developed with funding from the NSF, University of Washington, and the W.M. Keck Foundation. The incubators were deployed in 2003 in the walls of active black smoker chimneys in the Mothra Hydrothermal Field, Endeavour Segment of the Juan de Fuca Ridge. All instruments were successfully recovered in 2004, and one was redeployed for a short time-series experiment. Each 53-cm-long titanium assembly houses 27 temperature sensors that record temperatures from 0 to 500\\deg C within three discrete incubation chambers. Data are logged in a separate housing and inductively coupled links provide access to the data loggers without removal of the instruments. During the initial deployment, data were collected from 189 to 245 days, with up to ˜478° K temperature measurements completed for an individual instrument. Temperatures within the chimney

  16. Upper limit on CP violation in the B{sub s}{sup 0}-B{sub s}{sup 0} system

    SciTech Connect

    Berger, Ch.; Sehgal, L. M.

    2011-02-01

    In a previous publication we noted that the time dependence of an incoherent B{sup 0}-B{sup 0} mixture undergoes a qualitative change when the magnitude of CP violation {delta} exceeds a critical value. Requiring, on physical grounds, that the system evolve from an initial incoherent state to a final pure state in a monotonic way yields a new upper limit for {delta}. The recent measurement of the wrong charge semileptonic asymmetry of B{sub s}{sup 0} mesons presented by the D0 collaboration is outside this bound by 1 standard deviation. If this result is confirmed it implies the existence of a new quantum mechanical oscillation phenomenon.

  17. Setting an upper limit on the myoglobin iron(IV)hydroxide pK(a): insight into axial ligand tuning in heme protein catalysis.

    PubMed

    Yosca, Timothy H; Behan, Rachel K; Krest, Courtney M; Onderko, Elizabeth L; Langston, Matthew C; Green, Michael T

    2014-06-25

    To provide insight into the iron(IV)hydroxide pK(a) of histidine ligated heme proteins, we have probed the active site of myoglobin compound II over the pH range of 3.9-9.5, using EXAFS, Mössbauer, and resonance Raman spectroscopies. We find no indication of ferryl protonation over this pH range, allowing us to set an upper limit of 2.7 on the iron(IV)hydroxide pK(a) in myoglobin. Together with the recent determination of an iron(IV)hydroxide pK(a) ∼ 12 in the thiolate-ligated heme enzyme cytochrome P450, this result provides insight into Nature's ability to tune catalytic function through its choice of axial ligand.

  18. Radial transport of large-scale magnetic fields in accretion disks. I. Steady solutions and an upper limit on the vertical field strength

    SciTech Connect

    Okuzumi, Satoshi; Takeuchi, Taku; Muto, Takayuki

    2014-04-20

    Large-scale magnetic fields are key ingredients of magnetically driven disk accretion. We study how large-scale poloidal fields evolve in accretion disks, with the primary aim of quantifying the viability of magnetic accretion mechanisms in protoplanetary disks. We employ a kinematic mean-field model for poloidal field transport and focus on steady states where inward advection of a field balances with outward diffusion due to effective resistivities. We analytically derive the steady-state radial distribution of poloidal fields in highly conducting accretion disks. The analytic solution reveals an upper limit on the strength of large-scale vertical fields attainable in steady states. Any excess poloidal field will diffuse away within a finite time, and we demonstrate this with time-dependent numerical calculations of the mean-field equations. We apply this upper limit to large-scale vertical fields threading protoplanetary disks. We find that the maximum attainable strength is about 0.1 G at 1 AU, and about 1 mG at 10 AU from the central star. When combined with recent magnetic accretion models, the maximum field strength translates into the maximum steady-state accretion rate of ∼10{sup –7} M {sub ☉} yr{sup –1}, in agreement with observations. We also find that the maximum field strength is ∼1 kG at the surface of the central star provided that the disk extends down to the stellar surface. This implies that any excess stellar poloidal field of strength ≳ kG can be transported to the surrounding disk. This might in part resolve the magnetic flux problem in star formation.

  19. Absolute Equilibrium Entropy

    NASA Technical Reports Server (NTRS)

    Shebalin, John V.

    1997-01-01

    The entropy associated with absolute equilibrium ensemble theories of ideal, homogeneous, fluid and magneto-fluid turbulence is discussed and the three-dimensional fluid case is examined in detail. A sigma-function is defined, whose minimum value with respect to global parameters is the entropy. A comparison is made between the use of global functions sigma and phase functions H (associated with the development of various H-theorems of ideal turbulence). It is shown that the two approaches are complimentary though conceptually different: H-theorems show that an isolated system tends to equilibrium while sigma-functions allow the demonstration that entropy never decreases when two previously isolated systems are combined. This provides a more complete picture of entropy in the statistical mechanics of ideal fluids.

  20. Absolute oscillator strengths for 108 lines of Si I between 163 and 410 nanometers

    NASA Technical Reports Server (NTRS)

    Smith, Peter L.; Griesinger, Harriet E.; Cardon, Bartley L.; Huber, Martin C. E.; Tozzi, G. P.

    1987-01-01

    Measurements of neutral silicon oscillator strengths (f-values) obtained by absorption and emission techniques have been combined using the numerical procedure of Cardon et al. (1979) to produce 108 f-values for the Si I lines between 163 and 410 nm. Beam-foil-lifetime measurements were employed to determine the absolute scale. The present measurements have uncertainties of about 0.07 dex (+ or - 16 percent) at the 1-sigma level of confidence. Good agreement is obtained between the results and previous data. The data also provide upper limits for the f-values of 22 other lines and information on the lifetimes for 36 levels in Si I.

  1. Ages of young star clusters, massive blue stragglers, and the upper mass limit of stars: Analyzing age-dependent stellar mass functions

    SciTech Connect

    Schneider, F. R. N.; Izzard, R. G.; Langer, N.; Stolte, A.; Hußmann, B.; De Mink, S. E.; De Koter, A.; Sana, H.; Gvaramadze, V. V.; Liermann, A.

    2014-01-10

    Massive stars rapidly change their masses through strong stellar winds and mass transfer in binary systems. The latter aspect is important for populations of massive stars as more than 70% of all O stars are expected to interact with a binary companion during their lifetime. We show that such mass changes leave characteristic signatures in stellar mass functions of young star clusters that can be used to infer their ages and to identify products of binary evolution. We model the observed present-day mass functions of the young Galactic Arches and Quintuplet star clusters using our rapid binary evolution code. We find that the shaping of the mass function by stellar wind mass loss allows us to determine the cluster ages as 3.5 ± 0.7 Myr and 4.8 ± 1.1 Myr, respectively. Exploiting the effects of binary mass exchange on the cluster mass function, we find that the most massive stars in both clusters are rejuvenated products of binary mass transfer, i.e., the massive counterpart of classical blue straggler stars. This resolves the problem of an apparent age spread among the most luminous stars exceeding the expected duration of star formation in these clusters. We perform Monte Carlo simulations to probe stochastic sampling, which support the idea of the most massive stars being rejuvenated binary products. We find that the most massive star is expected to be a binary product after 1.0 ± 0.7 Myr in Arches and after 1.7 ± 1.0 Myr in Quintuplet. Today, the most massive 9 ± 3 stars in Arches and 8 ± 3 in Quintuplet are expected to be such objects. Our findings have strong implications for the stellar upper mass limit and solve the discrepancy between the claimed 150 M {sub ☉} limit and observations of four stars with initial masses of 165-320 M {sub ☉} in R136 and of supernova 2007bi, which is thought to be a pair-instability supernova from an initial 250 M {sub ☉} star. Using the stellar population of R136, we revise the upper mass limit to values in the range

  2. Combined CDF and D0 Upper Limits on Standard Model Higgs-Boson Production with up to 6.7 fb$^{-1}$ of Data

    SciTech Connect

    Not Available

    2010-07-01

    We combine results from CDF and D0 on direct searches for the standard model (SM) Higgs boson (H) in p{bar p} collisions at the Fermilab Tevatron at {radical}s = 1.96 TeV. Compared to the previous Tevatron Higgs search combination more data have been added, additional new channels have been incorporated, and some previously used channels have been reanalyzed to gain sensitivity. We use the latest parton distribution functions and gg {yields} H theoretical cross sections when comparing our limits to the SM predictions. With up to 5.9 fb{sup -1} of data analyzed at CDF, and up to 6.7 fb{sup -1} at D0, the 95% C.L. upper limits on Higgs boson production are factors of 1.56 and 0.68 the values of the SM cross section for a Higgs boson mass of m{sub H} = 115 GeV/c{sup 2} and 165 GeV/c{sup 2}. We exclude, at the 95% C.L., a new and larger region at high mass between 158 < m{sub H} < 175 GeV/c{sup 2}.

  3. [Study on the absolute spectral irradiation calibration method for far ultraviolet spectrometer in remote sensing].

    PubMed

    Yu, Lei; Lin, Guan-Yu; Chen, Bin

    2013-01-01

    The present paper studied spectral irradiation responsivities calibration method which can be applied to the far ultraviolet spectrometer for upper atmosphere remote sensing. It is difficult to realize the calibration for far ultraviolet spectrometer for many reasons. Standard instruments for far ultraviolet waveband calibration are few, the degree of the vacuum experiment system is required to be high, the stabilities of the experiment are hardly maintained, and the limitation of the far ultraviolet waveband makes traditional diffuser and the integrating sphere radiance calibration method difficult to be used. To solve these problems, a new absolute spectral irradiance calibration method was studied, which can be applied to the far ultraviolet calibration. We build a corresponding special vacuum experiment system to verify the calibration method. The light source system consists of a calibrated deuterium lamp, a vacuum ultraviolet monochromater and a collimating system. We used the calibrated detector to obtain the irradiance responsivities of it. The three instruments compose the calibration irradiance source. We used the "calibration irradiance source" to illuminate the spectrometer prototype and obtained the spectral irradiance responsivities. It realized the absolute spectral irradiance calibration for the far ultraviolet spectrometer utilizing the calibrated detector. The absolute uncertainty of the calibration is 7.7%. The method is significant for the ground irradiation calibration of the far ultraviolet spectrometer in upper atmosphere remote sensing.

  4. Absolute Instability near the Band Edge of Traveling-Wave Amplifiers

    NASA Astrophysics Data System (ADS)

    Hung, D. M. H.; Rittersdorf, I. M.; Zhang, P.; Chernin, D.; Lau, Y. Y.; Antonsen, T. M.; Luginsland, J. W.; Simon, D. H.; Gilgenbach, R. M.

    2015-09-01

    Applying the Briggs-Bers "pole-pinch" criterion to the exact transcendental dispersion relation of a dielectric traveling wave tube (TWT), we find that there is no absolute instability regardless of the beam current. We extend this analysis to the circuit band edges of a linear beam TWT by approximating the circuit mode as a hyperbola in the frequency-wave-number (ω -k ) plane and consider the weak coupling limit. For an operating mode whose group velocity is in the same direction as the beam mode, we find that the lower band edge is not subjected to absolute instability. At the upper band edge, we find a threshold beam current beyond which absolute instability is excited. The nonexistence of absolute instability in a linear beam TWT and the existence in a gyrotron TWT, both at the lower band edge, is contrasted. The general study given here is applicable to some contemporary TWTs such as metamaterial-based and advanced Smith-Purcell TWTs.

  5. Absolute Instability near the Band Edge of Traveling-Wave Amplifiers.

    PubMed

    Hung, D M H; Rittersdorf, I M; Zhang, P; Chernin, D; Lau, Y Y; Antonsen, T M; Luginsland, J W; Simon, D H; Gilgenbach, R M

    2015-09-18

    Applying the Briggs-Bers "pole-pinch" criterion to the exact transcendental dispersion relation of a dielectric traveling wave tube (TWT), we find that there is no absolute instability regardless of the beam current. We extend this analysis to the circuit band edges of a linear beam TWT by approximating the circuit mode as a hyperbola in the frequency-wave-number (ω-k) plane and consider the weak coupling limit. For an operating mode whose group velocity is in the same direction as the beam mode, we find that the lower band edge is not subjected to absolute instability. At the upper band edge, we find a threshold beam current beyond which absolute instability is excited. The nonexistence of absolute instability in a linear beam TWT and the existence in a gyrotron TWT, both at the lower band edge, is contrasted. The general study given here is applicable to some contemporary TWTs such as metamaterial-based and advanced Smith-Purcell TWTs.

  6. Absolute Instability near the Band Edge of Traveling-Wave Amplifiers.

    PubMed

    Hung, D M H; Rittersdorf, I M; Zhang, P; Chernin, D; Lau, Y Y; Antonsen, T M; Luginsland, J W; Simon, D H; Gilgenbach, R M

    2015-09-18

    Applying the Briggs-Bers "pole-pinch" criterion to the exact transcendental dispersion relation of a dielectric traveling wave tube (TWT), we find that there is no absolute instability regardless of the beam current. We extend this analysis to the circuit band edges of a linear beam TWT by approximating the circuit mode as a hyperbola in the frequency-wave-number (ω-k) plane and consider the weak coupling limit. For an operating mode whose group velocity is in the same direction as the beam mode, we find that the lower band edge is not subjected to absolute instability. At the upper band edge, we find a threshold beam current beyond which absolute instability is excited. The nonexistence of absolute instability in a linear beam TWT and the existence in a gyrotron TWT, both at the lower band edge, is contrasted. The general study given here is applicable to some contemporary TWTs such as metamaterial-based and advanced Smith-Purcell TWTs. PMID:26430996

  7. Upper thermal limits of cardiac function for Arctic cod Boreogadus saida, a key food web fish species in the Arctic Ocean.

    PubMed

    Drost, H E; Carmack, E C; Farrell, A P

    2014-06-01

    The objective of this study was to determine the upper thermal limits of Arctic cod Boreogadus saida by measuring the response of maximum heart rate (f(Hmax)) to acute warming. One set of fish were tested in a field laboratory in Cambridge Bay (CB), Nunavut (north of the Arctic Circle), and a second set were tested after air transport to and 6 month temperature acclimation at the Vancouver Aquarium (VA) laboratory. In both sets of tests, with B. saida acclimated to 0° C, f(Hmax) increased during acute warming up to temperatures considerably higher than the acclimation temperature and the near-freezing Arctic temperatures in which they are routinely found. Indeed, f(Hmax) increased steadily between 0.5 and 5.5° C, with no significant difference between the CB and VA tests (P > 0.05) and with an overall mean ± s.e. Q10 of 2.4 ± 0.5. The first Arrhenius breakpoint temperature (T(AB)) for f(Hmax) was also statistically indistinguishable for the two sets of tests (mean ± s.e. 3.2 ± 0.3 and 3.6 ± 0.3° C), suggesting that the temperature optimum for B. saida could be reliably measured after live transport to a more southerly laboratory location. Continued warming above 5.5° C revealed a large variability among individuals in the upper thermal limits that triggered cardiac arrhythmia (T(arr)), ranging from 10.2 to 15.2° C with mean ± s.e. 12.4 ± 0.4° C (n = 11) for the field study. A difference did exist between the CB and VA breakpoint temperatures when the Q10 value decreased below 2 (the Q10 breakpoint temperature; T(QB)) at 8.0 and 5.5° C, respectively. These results suggest that factors, other than thermal tolerance and associated cardiac performance, may influence the realized distribution of B. saida within the Arctic Circle. PMID:24814099

  8. Quantifying Upper Particle-size Limits of Salmonid Spawning Gravel: Analysis of Fall-run Chinook Salmon of the Sacramento River

    NASA Astrophysics Data System (ADS)

    Wooster, J. K.; Riebe, C. S.; Ligon, F. K.

    2008-12-01

    Reversing the decline of historically prolific runs of Chinook salmon (Oncorhynchus tshawytscha) remains a high priority of river restoration along the US Pacific Coast. One routinely implemented strategy is gravel injection, to supplement spawning habitat which has been depleted by gravel mining and bed coarsening below dams. Gravel augmentation is generally designed around a qualitatively assessed "preferred" median particle size. Implementation sites are not always ecologically ideal, because there often is little quantitative basis for determining where added gravel would be most suitable. Although gravel augmentation may increase spawning habitat, a more mechanistic design basis could reduce costs, improve efficiency, and make results more predictable. One key to developing better designs is a better method for characterizing existing spawning gravel deposits. Here we propose a series of mechanistically oriented hypotheses about the spawning suitability of natural gravels. One hypothesis is that there is an upper size limit on particles that can be moved by salmon. We expect that this limit depends on salmon size, water velocity and the size (and embeddedness) of surrounding rocks. Another hypothesis is that spawning success is related to percent coverage by immovable particles. A corollary hypothesis is that redds become irregular (and less productive) as percent coverage by immovable particles increases. Another related hypothesis is that redd-building success should approach zero at an upper threshold of coverage by immovable particles. We explored our hypotheses for fall-run Chinook in the Sacramento River. We collected grain size data, constructed facies maps of the bed, and delineated boundaries of spawning use at the peak of spawning, prior to the run's recent population decline. Our observations suggest that particles with intermediate axes diameters bigger than about 130 mm are not generally movable by fall run Chinook. Moreover we observed no

  9. Upper thermal limits of cardiac function for Arctic cod Boreogadus saida, a key food web fish species in the Arctic Ocean.

    PubMed

    Drost, H E; Carmack, E C; Farrell, A P

    2014-06-01

    The objective of this study was to determine the upper thermal limits of Arctic cod Boreogadus saida by measuring the response of maximum heart rate (f(Hmax)) to acute warming. One set of fish were tested in a field laboratory in Cambridge Bay (CB), Nunavut (north of the Arctic Circle), and a second set were tested after air transport to and 6 month temperature acclimation at the Vancouver Aquarium (VA) laboratory. In both sets of tests, with B. saida acclimated to 0° C, f(Hmax) increased during acute warming up to temperatures considerably higher than the acclimation temperature and the near-freezing Arctic temperatures in which they are routinely found. Indeed, f(Hmax) increased steadily between 0.5 and 5.5° C, with no significant difference between the CB and VA tests (P > 0.05) and with an overall mean ± s.e. Q10 of 2.4 ± 0.5. The first Arrhenius breakpoint temperature (T(AB)) for f(Hmax) was also statistically indistinguishable for the two sets of tests (mean ± s.e. 3.2 ± 0.3 and 3.6 ± 0.3° C), suggesting that the temperature optimum for B. saida could be reliably measured after live transport to a more southerly laboratory location. Continued warming above 5.5° C revealed a large variability among individuals in the upper thermal limits that triggered cardiac arrhythmia (T(arr)), ranging from 10.2 to 15.2° C with mean ± s.e. 12.4 ± 0.4° C (n = 11) for the field study. A difference did exist between the CB and VA breakpoint temperatures when the Q10 value decreased below 2 (the Q10 breakpoint temperature; T(QB)) at 8.0 and 5.5° C, respectively. These results suggest that factors, other than thermal tolerance and associated cardiac performance, may influence the realized distribution of B. saida within the Arctic Circle.

  10. Combined Use of Absolute and Differential Seismic Arrival Time Data to Improve Absolute Event Location

    NASA Astrophysics Data System (ADS)

    Myers, S.; Johannesson, G.

    2012-12-01

    Arrival time measurements based on waveform cross correlation are becoming more common as advanced signal processing methods are applied to seismic data archives and real-time data streams. Waveform correlation can precisely measure the time difference between the arrival of two phases, and differential time data can be used to constrain relative location of events. Absolute locations are needed for many applications, which generally requires the use of absolute time data. Current methods for measuring absolute time data are approximately two orders of magnitude less precise than differential time measurements. To exploit the strengths of both absolute and differential time data, we extend our multiple-event location method Bayesloc, which previously used absolute time data only, to include the use of differential time measurements that are based on waveform cross correlation. Fundamentally, Bayesloc is a formulation of the joint probability over all parameters comprising the multiple event location system. The Markov-Chain Monte Carlo method is used to sample from the joint probability distribution given arrival data sets. The differential time component of Bayesloc includes scaling a stochastic estimate of differential time measurement precision based the waveform correlation coefficient for each datum. For a regional-distance synthetic data set with absolute and differential time measurement error of 0.25 seconds and 0.01 second, respectively, epicenter location accuracy is improved from and average of 1.05 km when solely absolute time data are used to 0.28 km when absolute and differential time data are used jointly (73% improvement). The improvement in absolute location accuracy is the result of conditionally limiting absolute location probability regions based on the precise relative position with respect to neighboring events. Bayesloc estimates of data precision are found to be accurate for the synthetic test, with absolute and differential time measurement

  11. Combined Tevatron upper limit on gg{yields}H{yields}W{sup +}W{sup -} and constraints on the Higgs boson mass in fourth-generation fermion models

    SciTech Connect

    Aaltonen, T.; Mehtala, P.; Orava, R.; Osterberg, K.; Saarikko, H.; Remortel, N. van; Abazov, V. M.; Alexeev, G. D.; Artikov, A.; Budagov, J.; Chokheli, D.; Glagolev, V.; Golovanov, G.; Kharzheev, Y. N.; Malyshev, V. L.; Poukhov, O.; Prokoshin, F.; Semenov, A.; Simonenko, A.; Sisakyan, A.

    2010-07-01

    We combine results from searches by the CDF and D0 collaborations for a standard model Higgs boson (H) in the process gg{yields}H{yields}W{sup +}W{sup -} in pp collisions at the Fermilab Tevatron Collider at {radical}(s)=1.96 TeV. With 4.8 fb{sup -1} of integrated luminosity analyzed at CDF and 5.4 fb{sup -1} at D0, the 95% confidence level upper limit on {sigma}(gg{yields}H)xB(H{yields}W{sup +}W{sup -}) is 1.75 pb at m{sub H}=120 GeV, 0.38 pb at m{sub H}=165 GeV, and 0.83 pb at m{sub H}=200 GeV. Assuming the presence of a fourth sequential generation of fermions with large masses, we exclude at the 95% confidence level a standard-model-like Higgs boson with a mass between 131 and 204 GeV.

  12. Combined Tevatron upper limit on gg -> H -> W^+W^- and constraints on the Higgs boson mass in fourth-generation fermion models

    SciTech Connect

    Aaltonen, T.; Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, M.; Adams, T.; Adelman, J.; Aguilo, E.; Alexeev, G.D.; Alkhazov, G.; /Helsinki Inst. of Phys. /Dubna, JINR /Oklahoma U. /Michigan State U. /Tata Inst. /Illinois U., Chicago /Florida State U. /Chicago U., EFI /Simon Fraser U. /York U., Canada /St. Petersburg, INP /Illinois U., Urbana /Sao Paulo, IFT /Munich U. /University Coll. London /Oxford U. /St. Petersburg, INP /Duke U. /Kyungpook Natl. U. /Chonnam Natl. U. /Florida U. /Osaka City U.

    2010-05-01

    We combine results from searches by the CDF and D0 collaborations for a standard model Higgs boson (H) in the process gg {yields} H {yields} W{sup +}W{sup -} in p{bar p} collisions at the Fermilab Tevatron Collider at {radical}s = 1.o6 TeV. With 4.8 fb{sup -1} of itnegrated luminosity analyzed at CDF and 5.4 fb{sup -1} at D0, the 95% Confidence Level upper limit on {sigma}(gg {yields} H) x {Beta}(H {yields} W{sup +}W{sup -}) is 1.75 pb at m{sub H} = 120 GeV, 0.38 pb at m{sub H} = 165 GeV, and 0.83 pb at m{sub H} = 200 GeV. Assuming the presence of a fourth sequential generation of fermions with large masses, they exclude at the 95% Confidence Level a standard-model-like Higgs boson with a mass between 131 and 204 Gev.

  13. Absolute Identification by Relative Judgment

    ERIC Educational Resources Information Center

    Stewart, Neil; Brown, Gordon D. A.; Chater, Nick

    2005-01-01

    In unidimensional absolute identification tasks, participants identify stimuli that vary along a single dimension. Performance is surprisingly poor compared with discrimination of the same stimuli. Existing models assume that identification is achieved using long-term representations of absolute magnitudes. The authors propose an alternative…

  14. Be Resolute about Absolute Value

    ERIC Educational Resources Information Center

    Kidd, Margaret L.

    2007-01-01

    This article explores how conceptualization of absolute value can start long before it is introduced. The manner in which absolute value is introduced to students in middle school has far-reaching consequences for their future mathematical understanding. It begins to lay the foundation for students' understanding of algebra, which can change…

  15. Upper limits to the reaction rate coefficients of C(n)(-) and C(n)H(-) (n = 2, 4, 6) with molecular hydrogen.

    PubMed

    Endres, Eric S; Lakhmanskaya, Olga; Hauser, Daniel; Huber, Stefan E; Best, Thorsten; Kumar, Sunil S; Probst, Michael; Wester, Roland

    2014-08-21

    In the interstellar medium (ISM) ion–molecule reactions play a key role in forming complex molecules. Since 2006, after the radioastronomical discovery of the first of by now six interstellar anions, interest has grown in understanding the formation and destruction pathways of negative ions in the ISM. Experiments have focused on reactions and photodetachment of the identified negatively charged ions. Hints were found that the reactions of CnH(–) with H2 may proceed with a low (<10(–13) cm(3) s(–1)), but finite rate [Eichelberger, B.; et al. Astrophys. J. 2007, 667, 1283]. Because of the high abundance of molecular hydrogen in the ISM, a precise knowledge of the reaction rate is needed for a better understanding of the low-temperature chemistry in the ISM. A suitable tool to analyze rare reactions is the 22-pole radiofrequency ion trap. Here, we report on reaction rates for Cn(–) and CnH(–) (n = 2, 4, 6) with buffer gas temperatures of H2 at 12 and 300 K. Our experiments show the absence of these reactions with an upper limit to the rate coefficients between 4 × 10(–16) and 5 × 10(–15) cm(3) s(–1), except for the case of C2(–), which does react with a finite rate with H2 at low temperatures. For the cases of C2H(–) and C4H(–), the experimental results were confirmed with quantum chemical calculations. In addition, the possible influence of a residual reactivity on the abundance of C4H(–) and C6H(–) in the ISM were estimated on the basis of a gas-phase chemical model based on the KIDA database. We found that the simulated ion abundances are already unaffected if reaction rate coefficients with H2 were below 10(–14) cm(3) s(–1).

  16. Detections and Sensitive Upper Limits for Methane and Related Trace Gases on Mars during 2003-2014, and planned extensions in 2016

    NASA Astrophysics Data System (ADS)

    Mumma, Michael J.; Villanueva, Geronimo L.; Novak, Robert E.

    2015-11-01

    Five groups report methane detections on Mars; all results suggest local release and high temporal variability [1-7]. Our team searched for CH4 on many dates and seasons and detected it on several dates [1, 9, 10]. TLS (Curiosity rover) reported methane upper limits [6], and then detections [7] that were consistent in size with earlier reports and that also showed rapid modulation of CH4 abundance.[8] argued that absorption features assigned to Mars 12CH4 by [1] might instead be weak lines of terrestrial 13CH4. If not properly removed, terrestrial 13CH4 signatures would appear on the blue wing of terrestrial 12CH4 even when Mars is red-shifted - but they do not (Fig. S6 of [1]), demonstrating that terrestrial signatures were correctly removed. [9] demonstrated that including the dependence of δ13CH4 with altitude did not affect the residual features, nor did taking δ13CH4 as zero. Were δ13CH4 important, its omission would have overemphasized the depth of 13CH4 terrestrial absorption, introducing emission features in the residual spectra [1]. However, the residual features are seen in absorption, establishing their origin as non-terrestrial - [8] now agrees with this view.We later reported results for multiple organic gases (CH4, CH3OH, H2CO, C2H6, C2H2, C2H4), hydroperoxyl (HO2), three nitriles (N2O, NH3, HCN) and two chlorinated species (HCl, CH3Cl) [9]. Most of these species cannot be detected with current space assets, owing to instrumental limitations (e.g., spectral resolving power). However, the high resolution infrared spectrometers (NOMAD, ACS) on ExoMars 2016 (Trace Gas Orbiter) will begin measurements in late 2016. In solar occultation, TGO sensitivities will far exceed prior capabilities.We published detailed hemispheric maps of H2O and HDO on Mars, inferring the size of a lost early ocean [10]. In 2016, we plan to acquire 3-D spatial maps of HDO and H2O with ALMA, and improved maps of organics with iSHELL/NASA-IRTF.References: [1] Mumma et al. Sci09

  17. Singular perturbation of absolute stability.

    NASA Technical Reports Server (NTRS)

    Siljak, D. D.

    1972-01-01

    It was previously shown (author, 1969) that the regions of absolute stability in the parameter space can be determined when the parameters appear on the right-hand side of the system equations, i.e., the regular case. Here, the effect on absolute stability of a small parameter attached to higher derivatives in the equations (the singular case) is studied. The Lur'e-Postnikov class of nonlinear systems is considered.

  18. Absolute-magnitude distributions of supernovae

    SciTech Connect

    Richardson, Dean; Wright, John; Jenkins III, Robert L.; Maddox, Larry

    2014-05-01

    The absolute-magnitude distributions of seven supernova (SN) types are presented. The data used here were primarily taken from the Asiago Supernova Catalogue, but were supplemented with additional data. We accounted for both foreground and host-galaxy extinction. A bootstrap method is used to correct the samples for Malmquist bias. Separately, we generate volume-limited samples, restricted to events within 100 Mpc. We find that the superluminous events (M{sub B} < –21) make up only about 0.1% of all SNe in the bias-corrected sample. The subluminous events (M{sub B} > –15) make up about 3%. The normal Ia distribution was the brightest with a mean absolute blue magnitude of –19.25. The IIP distribution was the dimmest at –16.75.

  19. Absolute radiometric calibration of advanced remote sensing systems

    NASA Technical Reports Server (NTRS)

    Slater, P. N.

    1982-01-01

    The distinction between the uses of relative and absolute spectroradiometric calibration of remote sensing systems is discussed. The advantages of detector-based absolute calibration are described, and the categories of relative and absolute system calibrations are listed. The limitations and problems associated with three common methods used for the absolute calibration of remote sensing systems are addressed. Two methods are proposed for the in-flight absolute calibration of advanced multispectral linear array systems. One makes use of a sun-illuminated panel in front of the sensor, the radiance of which is monitored by a spectrally flat pyroelectric radiometer. The other uses a large, uniform, high-radiance reference ground surface. The ground and atmospheric measurements required as input to a radiative transfer program to predict the radiance level at the entrance pupil of the orbital sensor are discussed, and the ground instrumentation is described.

  20. 1.99 Ga mafic dykes of the Lewisian Gneiss Complex of Scotland: An upper age limit for the Palaeoproterozoic Loch Maree Group

    NASA Astrophysics Data System (ADS)

    Baker, Thomas; Prave, Tony; Spencer, Christopher

    2015-04-01

    Mafic dyke swarms are often used as geochronological markers, as they are widespread and emplaced over short timespans. The ca. 2.4 Ga Scourie dyke swarm is one such example that has played a key role in understanding the complex tectonic and metamorphic history of the Lewisian Gneiss Complex of Scotland (LGC), part of the North Atlantic Craton (NAC). The LGC consists of Archean and Palaeoproterozoic terranes that experienced polyphase deformation prior to their assembly at ca. 1.8 Ga. Zircons separated from a doleritic dyke from the Gairloch terrane have yielded a concordant U-Th-Pb age (1,989 +4.3 / -0.99 Ma) using the ID-TIMS method. The doleritic dyke is emplaced in Lewisian gneiss that experienced both granulite and amphibolite-facies metamorphism. Partial recrystallisation and amphibolitisation of the dyke demonstrate that it pre-dates the most recent (Laxfordian) amphibolite-facies metamorphic event. The age obtained from the dyke overlaps the U-Pb age of a previously dated olivine gabbro dyke from the Assynt terrane (1,992 Ma). These combined ages provide strong corroborating evidence for a ca. 2.0 Ga mafic dyke swarm event, distinct from the older ca. 2.4 Ga Scourie dyke event known from elsewhere in the LGC. The existence of a ca. 2.0 Ga mafic dyke swarm provides an upper age limit for the Loch Maree Group (LMG), a Palaeoproterozoic succession of metasediment and metavolcanic rocks that overlie the LGC and which are not cross-cut by the Scourie dykes. This study proposes that a period of crustal extension took place in the region at ca. 2.0 Ga. Later, subduction may have resulted in the accretion of the LMG and the adjacent Ard Gneiss, which has previously been regarded as a magmatic arc. The ca. 1.9 Ga age of the earliest stage of the Laxfordian metamorphic event, which affected the LMG, could therefore mark the onset of collision. This sequence of events can be correlated with other coeval areas of the NAC, including the Nagssugtoqidian mobile belt of

  1. Absolute Radiometric Calibration of EUNIS-06

    NASA Technical Reports Server (NTRS)

    Thomas, R. J.; Rabin, D. M.; Kent, B. J.; Paustian, W.

    2007-01-01

    The Extreme-Ultraviolet Normal-Incidence Spectrometer (EUNIS) is a soundingrocket payload that obtains imaged high-resolution spectra of individual solar features, providing information about the Sun's corona and upper transition region. Shortly after its successful initial flight last year, a complete end-to-end calibration was carried out to determine the instrument's absolute radiometric response over its Longwave bandpass of 300 - 370A. The measurements were done at the Rutherford-Appleton Laboratory (RAL) in England, using the same vacuum facility and EUV radiation source used in the pre-flight calibrations of both SOHO/CDS and Hinode/EIS, as well as in three post-flight calibrations of our SERTS sounding rocket payload, the precursor to EUNIS. The unique radiation source provided by the Physikalisch-Technische Bundesanstalt (PTB) had been calibrated to an absolute accuracy of 7% (l-sigma) at 12 wavelengths covering our bandpass directly against the Berlin electron storage ring BESSY, which is itself a primary radiometric source standard. Scans of the EUNIS aperture were made to determine the instrument's absolute spectral sensitivity to +- 25%, considering all sources of error, and demonstrate that EUNIS-06 was the most sensitive solar E W spectrometer yet flown. The results will be matched against prior calibrations which relied on combining measurements of individual optical components, and on comparisons with theoretically predicted 'insensitive' line ratios. Coordinated observations were made during the EUNIS-06 flight by SOHO/CDS and EIT that will allow re-calibrations of those instruments as well. In addition, future EUNIS flights will provide similar calibration updates for TRACE, Hinode/EIS, and STEREO/SECCHI/EUVI.

  2. Essential anatomy for contemporary upper lid blepharoplasty.

    PubMed

    Siegel, R J

    1993-04-01

    A clear understanding of upper eyelid anatomy is an absolute prerequisite for performing advanced invagination-type blepharoplasty. This article describes the author's simple, systematic approach to intraoperative identification of the levator aponeurosis as well as the other key layers of fascia in the upper lid.

  3. Absolute flux scale for radioastronomy

    SciTech Connect

    Ivanov, V.P.; Stankevich, K.S.

    1986-07-01

    The authors propose and provide support for a new absolute flux scale for radio astronomy, which is not encumbered with the inadequacies of the previous scales. In constructing it the method of relative spectra was used (a powerful tool for choosing reference spectra). A review is given of previous flux scales. The authors compare the AIS scale with the scale they propose. Both scales are based on absolute measurements by the ''artificial moon'' method, and they are practically coincident in the range from 0.96 to 6 GHz. At frequencies above 6 GHz, 0.96 GHz, the AIS scale is overestimated because of incorrect extrapolation of the spectra of the primary and secondary standards. The major results which have emerged from this review of absolute scales in radio astronomy are summarized.

  4. Absolute quantum cutting efficiency of Tb{sup 3+}-Yb{sup 3+} co-doped glass

    SciTech Connect

    Duan, Qianqian; Qin, Feng; Zhang, Zhiguo; Zhao, Hua; Cao, Wenwu

    2013-12-07

    The absolute quantum cutting efficiency of Tb{sup 3+}-Yb{sup 3+} co-doped glass was quantitatively measured by an integrating sphere detection system, which is independent of the excitation power. As the Yb{sup 3+} concentration increases, the near infrared quantum efficiency exhibited an exponential growth with an upper limit of 13.5%, but the visible light efficiency was reduced rapidly. As a result, the total quantum efficiency monotonically decreases rather than increases as theory predicted. In fact, the absolute quantum efficiency was far less than the theoretical value due to the low radiative efficiency of Tb{sup 3+} (<61%) and significant cross-relaxation nonradiative loss between Yb{sup 3+} ions.

  5. Relativistic Absolutism in Moral Education.

    ERIC Educational Resources Information Center

    Vogt, W. Paul

    1982-01-01

    Discusses Emile Durkheim's "Moral Education: A Study in the Theory and Application of the Sociology of Education," which holds that morally healthy societies may vary in culture and organization but must possess absolute rules of moral behavior. Compares this moral theory with current theory and practice of American educators. (MJL)

  6. Absolute transition probabilities of phosphorus.

    NASA Technical Reports Server (NTRS)

    Miller, M. H.; Roig, R. A.; Bengtson, R. D.

    1971-01-01

    Use of a gas-driven shock tube to measure the absolute strengths of 21 P I lines and 126 P II lines (from 3300 to 6900 A). Accuracy for prominent, isolated neutral and ionic lines is estimated to be 28 to 40% and 18 to 30%, respectively. The data and the corresponding theoretical predictions are examined for conformity with the sum rules.-

  7. Optomechanics for absolute rotation detection

    NASA Astrophysics Data System (ADS)

    Davuluri, Sankar

    2016-07-01

    In this article, we present an application of optomechanical cavity for the absolute rotation detection. The optomechanical cavity is arranged in a Michelson interferometer in such a way that the classical centrifugal force due to rotation changes the length of the optomechanical cavity. The change in the cavity length induces a shift in the frequency of the cavity mode. The phase shift corresponding to the frequency shift in the cavity mode is measured at the interferometer output to estimate the angular velocity of absolute rotation. We derived an analytic expression to estimate the minimum detectable rotation rate in our scheme for a given optomechanical cavity. Temperature dependence of the rotation detection sensitivity is studied.

  8. Moral absolutism and ectopic pregnancy.

    PubMed

    Kaczor, C

    2001-02-01

    If one accepts a version of absolutism that excludes the intentional killing of any innocent human person from conception to natural death, ectopic pregnancy poses vexing difficulties. Given that the embryonic life almost certainly will die anyway, how can one retain one's moral principle and yet adequately respond to a situation that gravely threatens the life of the mother and her future fertility? The four options of treatment most often discussed in the literature are non-intervention, salpingectomy (removal of tube with embryo), salpingostomy (removal of embryo alone), and use of methotrexate (MXT). In this essay, I review these four options and introduce a fifth (the milking technique). In order to assess these options in terms of the absolutism mentioned, it will also be necessary to discuss various accounts of the intention/foresight distinction. I conclude that salpingectomy, salpingostomy, and the milking technique are compatible with absolutist presuppositions, but not the use of methotrexate.

  9. Moral absolutism and ectopic pregnancy.

    PubMed

    Kaczor, C

    2001-02-01

    If one accepts a version of absolutism that excludes the intentional killing of any innocent human person from conception to natural death, ectopic pregnancy poses vexing difficulties. Given that the embryonic life almost certainly will die anyway, how can one retain one's moral principle and yet adequately respond to a situation that gravely threatens the life of the mother and her future fertility? The four options of treatment most often discussed in the literature are non-intervention, salpingectomy (removal of tube with embryo), salpingostomy (removal of embryo alone), and use of methotrexate (MXT). In this essay, I review these four options and introduce a fifth (the milking technique). In order to assess these options in terms of the absolutism mentioned, it will also be necessary to discuss various accounts of the intention/foresight distinction. I conclude that salpingectomy, salpingostomy, and the milking technique are compatible with absolutist presuppositions, but not the use of methotrexate. PMID:11262641

  10. The Absolute Spectrum Polarimeter (ASP)

    NASA Technical Reports Server (NTRS)

    Kogut, A. J.

    2010-01-01

    The Absolute Spectrum Polarimeter (ASP) is an Explorer-class mission to map the absolute intensity and linear polarization of the cosmic microwave background and diffuse astrophysical foregrounds over the full sky from 30 GHz to 5 THz. The principal science goal is the detection and characterization of linear polarization from an inflationary epoch in the early universe, with tensor-to-scalar ratio r much greater than 1O(raised to the power of { -3}) and Compton distortion y < 10 (raised to the power of{-6}). We describe the ASP instrument and mission architecture needed to detect the signature of an inflationary epoch in the early universe using only 4 semiconductor bolometers.

  11. Classification images predict absolute efficiency.

    PubMed

    Murray, Richard F; Bennett, Patrick J; Sekuler, Allison B

    2005-02-24

    How well do classification images characterize human observers' strategies in perceptual tasks? We show mathematically that from the classification image of a noisy linear observer, it is possible to recover the observer's absolute efficiency. If we could similarly predict human observers' performance from their classification images, this would suggest that the linear model that underlies use of the classification image method is adequate over the small range of stimuli typically encountered in a classification image experiment, and that a classification image captures most important aspects of human observers' performance over this range. In a contrast discrimination task and in a shape discrimination task, we found that observers' absolute efficiencies were generally well predicted by their classification images, although consistently slightly (approximately 13%) higher than predicted. We consider whether a number of plausible nonlinearities can account for the slight under prediction, and of these we find that only a form of phase uncertainty can account for the discrepancy.

  12. Absolute calibration of optical flats

    DOEpatents

    Sommargren, Gary E.

    2005-04-05

    The invention uses the phase shifting diffraction interferometer (PSDI) to provide a true point-by-point measurement of absolute flatness over the surface of optical flats. Beams exiting the fiber optics in a PSDI have perfect spherical wavefronts. The measurement beam is reflected from the optical flat and passed through an auxiliary optic to then be combined with the reference beam on a CCD. The combined beams include phase errors due to both the optic under test and the auxiliary optic. Standard phase extraction algorithms are used to calculate this combined phase error. The optical flat is then removed from the system and the measurement fiber is moved to recombine the two beams. The newly combined beams include only the phase errors due to the auxiliary optic. When the second phase measurement is subtracted from the first phase measurement, the absolute phase error of the optical flat is obtained.

  13. Glacier-fed Irrigation Systems in upper Hunza: Evolution and Limitations of socio-hydrological Interactions in the Karakoram, northern Pakistan

    NASA Astrophysics Data System (ADS)

    Parveen, Sitara; Winiger, Matthias; Schmidt, Susanne; Nüsser, Marcus

    2016-04-01

    Unlike other Himalayan regions, where glacier retreat dominates, glaciers in the upper Indus catchment are characterised by an overall increase of total snow and ice volumes with significant regional differences. However, there are many cases where glacier termini are in retreat and where ablation reduces glacier surfaces, often resulting in the desiccation of irrigation channels across lateral moraines. The question of how glacial dynamics affect the livelihoods of mountain communities living in close proximity to these ice bodies has been largely neglected. Local irrigation systems in high mountain regions are unique examples of socio-hydrological interactions, which are characterised by an interplay of site-specific glacio-hydrological conditions, socio-economic development, institutional arrangements and external development interventions. Reliable crop production requires constant and sufficient melt-water supply from glaciers and snowfields. Based on three case studies, this study describes and analyzes the structure and dynamics of irrigation systems in upper Hunza, located in the western Karakoram, Pakistan. In these deeply incised and arid valleys, glacier and snow melt-water are the primary water sources for agricultural production. The study shows how glacio-fluvial dynamics impact upon irrigation systems and land-use practices, and how in turn, local communities adapt to these changing conditions: framed here as coupled socio-hydrological interactions. A combined methodological approach, including field observations, interviews, mapping and remote sensing analysis, was used to trace historical and recent changes of irrigation networks and land-use patterns.

  14. Generating Light from Upper Excited Triplet States: A Contribution to the Indirect Singlet Yield of a Polymer OLED, Helping to Exceed the 25% Singlet Exciton Limit

    PubMed Central

    Jankus, Vygintas; Aydemir, Murat; Dias, Fernando B.

    2016-01-01

    The mechanisms by which light is generated in an organic light emitting diode have slowly been elucidated over the last ten years. The role of triplet annihilation has demonstrated how the “spin statistical limit” can be surpassed, but it cannot account for all light produced in the most efficient devices. Here, a further mechanism is demonstrated by which upper excited triplet states can also contribute to indirect singlet production and delayed fluorescence. Since in a device the population of these TN states is large, this indirect radiative decay channel can contribute a sizeable fraction of the total emission measured from a device. The role of intra‐ and interchain charge transfer states is critical in underpinning this mechanism. PMID:27610333

  15. Generating Light from Upper Excited Triplet States: A Contribution to the Indirect Singlet Yield of a Polymer OLED, Helping to Exceed the 25% Singlet Exciton Limit

    PubMed Central

    Jankus, Vygintas; Aydemir, Murat; Dias, Fernando B.

    2016-01-01

    The mechanisms by which light is generated in an organic light emitting diode have slowly been elucidated over the last ten years. The role of triplet annihilation has demonstrated how the “spin statistical limit” can be surpassed, but it cannot account for all light produced in the most efficient devices. Here, a further mechanism is demonstrated by which upper excited triplet states can also contribute to indirect singlet production and delayed fluorescence. Since in a device the population of these TN states is large, this indirect radiative decay channel can contribute a sizeable fraction of the total emission measured from a device. The role of intra‐ and interchain charge transfer states is critical in underpinning this mechanism.

  16. ASTROMETRY AND RADIAL VELOCITIES OF THE PLANET HOST M DWARF GJ 317: NEW TRIGONOMETRIC DISTANCE, METALLICITY, AND UPPER LIMIT TO THE MASS OF GJ 317b

    SciTech Connect

    Anglada-Escude, Guillem; Boss, Alan P.; Weinberger, Alycia J.; Butler, R. Paul; Thompson, Ian B.; Vogt, Steven S.; Rivera, Eugenio J.

    2012-02-10

    We have obtained precision astrometry of the planet host M dwarf GJ 317 in the framework of the Carnegie Astrometric Planet Search project. The new astrometric measurements give a distance determination of 15.3 pc, 65% further than previous estimates. The resulting absolute magnitudes suggest that it is metal-rich and more massive than previously assumed. This result strengthens the correlation between high metallicity and the presence of gas giants around low-mass stars. At 15.3 pc, the minimal astrometric amplitude for planet candidate GJ 317b is 0.3 mas (edge-on orbit), just below our astrometric sensitivity. However, given the relatively large number of observations and good astrometric precision, a Bayesian Monte Carlo Markov Chain analysis indicates that the mass of planet b has to be smaller than twice the minimum mass with a 99% confidence level, with a most likely value of 2.5 M{sub Jup}. Additional radial velocity (RV) measurements obtained with Keck by the Lick-Carnegie Planet search program confirm the presence of an additional very long period planet candidate, with a period of 20 years or more. Even though such an object will imprint a large astrometric wobble on the star, its curvature is yet not evident in the astrometry. Given high metallicity, and the trend indicating that multiple systems are rich in low-mass companions, this system is likely to host additional low-mass planets in its habitable zone that can be readily detected with state-of-the-art optical and near-infrared RV measurements.

  17. The AFGL absolute gravity program

    NASA Technical Reports Server (NTRS)

    Hammond, J. A.; Iliff, R. L.

    1978-01-01

    A brief discussion of the AFGL's (Air Force Geophysics Laboratory) program in absolute gravity is presented. Support of outside work and in-house studies relating to gravity instrumentation are discussed. A description of the current transportable system is included and the latest results are presented. These results show good agreement with measurements at the AFGL site by an Italian system. The accuracy obtained by the transportable apparatus is better than 0.1 microns sq sec 10 microgal and agreement with previous measurements is within the combined uncertainties of the measurements.

  18. Familial Aggregation of Absolute Pitch

    PubMed Central

    Baharloo, Siamak; Service, Susan K.; Risch, Neil; Gitschier, Jane; Freimer, Nelson B.

    2000-01-01

    Absolute pitch (AP) is a behavioral trait that is defined as the ability to identify the pitch of tones in the absence of a reference pitch. AP is an ideal phenotype for investigation of gene and environment interactions in the development of complex human behaviors. Individuals who score exceptionally well on formalized auditory tests of pitch perception are designated as “AP-1.” As described in this report, auditory testing of siblings of AP-1 probands and of a control sample indicates that AP-1 aggregates in families. The implications of this finding for the mapping of loci for AP-1 predisposition are discussed. PMID:10924408

  19. Experimental results for absolute cylindrical wavefront testing

    NASA Astrophysics Data System (ADS)

    Reardon, Patrick J.; Alatawi, Ayshah

    2014-09-01

    Applications for Cylindrical and near-cylindrical surfaces are ever-increasing. However, fabrication of high quality cylindrical surfaces is limited by the difficulty of accurate and affordable metrology. Absolute testing of such surfaces represents a challenge to the optical testing community as cylindrical reference wavefronts are difficult to produce. In this paper, preliminary results for a new method of absolute testing of cylindrical wavefronts are presented. The method is based on the merging of the random ball test method with the fiber optic reference test. The random ball test assumes a large number of interferograms of a good quality sphere with errors that are statistically distributed such that the average of the errors goes to zero. The fiber optic reference test utilizes a specially processed optical fiber to provide a clean high quality reference wave from an incident line focus from the cylindrical wave under test. By taking measurements at different rotation and translations of the fiber, an analogous procedure can be employed to determine the quality of the converging cylindrical wavefront with high accuracy. This paper presents and discusses the results of recent tests of this method using a null optic formed by a COTS cylindrical lens and a free-form polished corrector element.

  20. Absolute Electron Extraction Efficiency of Liquid Xenon

    NASA Astrophysics Data System (ADS)

    Kamdin, Katayun; Mizrachi, Eli; Morad, James; Sorensen, Peter

    2016-03-01

    Dual phase liquid/gas xenon time projection chambers (TPCs) currently set the world's most sensitive limits on weakly interacting massive particles (WIMPs), a favored dark matter candidate. These detectors rely on extracting electrons from liquid xenon into gaseous xenon, where they produce proportional scintillation. The proportional scintillation from the extracted electrons serves to internally amplify the WIMP signal; even a single extracted electron is detectable. Credible dark matter searches can proceed with electron extraction efficiency (EEE) lower than 100%. However, electrons systematically left at the liquid/gas boundary are a concern. Possible effects include spontaneous single or multi-electron proportional scintillation signals in the gas, or charging of the liquid/gas interface or detector materials. Understanding EEE is consequently a serious concern for this class of rare event search detectors. Previous EEE measurements have mostly been relative, not absolute, assuming efficiency plateaus at 100%. I will present an absolute EEE measurement with a small liquid/gas xenon TPC test bed located at Lawrence Berkeley National Laboratory.

  1. TWO UPPER LIMITS ON THE ROSSITER-MCLAUGHLIN EFFECT, WITH DIFFERING IMPLICATIONS: WASP-1 HAS A HIGH OBLIQUITY AND WASP-2 IS INDETERMINATE

    SciTech Connect

    Albrecht, Simon; Winn, Joshua N.; Hirano, Teruyuki; Johnson, John Asher; Paul Butler, R.; Crane, Jeffrey D.; Shectman, Stephen A.; Thompson, Ian B.; Narita, Norio; Sato, Bun'ei; Enya, Keigo; Fischer, Debra

    2011-09-01

    We present precise radial-velocity (RV) measurements of WASP-1 and WASP-2 throughout transits of their giant planets. Our goal was to detect the Rossiter-McLaughlin (RM) effect, the anomalous RV observed during eclipses of rotating stars, which can be used to study the obliquities of planet-hosting stars. For WASP-1, a weak signal of a prograde orbit was detected with {approx}2{sigma} confidence, and for WASP-2 no signal was detected. The resulting upper bounds on the RM amplitude have different implications for these two systems because of the contrasting transit geometries and the stellar types. Because WASP-1 is an F7V star, and such stars are typically rapid rotators, the most probable reason for the suppression of the RM effect is that the star is viewed nearly pole-on. This implies that the WASP-1 star has a high obliquity with respect to the edge-on planetary orbit. Because WASP-2 is a K1V star, and is expected to be a slow rotator, no firm conclusion can be drawn about the stellar obliquity. Our data and our analysis contradict an earlier claim that WASP-2b has a retrograde orbit, thereby revoking this system's status as an exception to the pattern that cool stars have low obliquities.

  2. Absolute Measurement of Electron Cloud Density

    SciTech Connect

    Covo, M K; Molvik, A W; Cohen, R H; Friedman, A; Seidl, P A; Logan, G; Bieniosek, F; Baca, D; Vay, J; Orlando, E; Vujic, J L

    2007-06-21

    Beam interaction with background gas and walls produces ubiquitous clouds of stray electrons that frequently limit the performance of particle accelerator and storage rings. Counterintuitively we obtained the electron cloud accumulation by measuring the expelled ions that are originated from the beam-background gas interaction, rather than by measuring electrons that reach the walls. The kinetic ion energy measured with a retarding field analyzer (RFA) maps the depressed beam space-charge potential and provides the dynamic electron cloud density. Clearing electrode current measurements give the static electron cloud background that complements and corroborates with the RFA measurements, providing an absolute measurement of electron cloud density during a 5 {micro}s duration beam pulse in a drift region of the magnetic transport section of the High-Current Experiment (HCX) at LBNL.

  3. Current Absolute Plate Velocities Inferred from Hotspot Tracks, Comparison with Absolute Velocities Inferred from Seismic Anisotropy, and Bounds on Rates of Motion Between Groups of Hotspots

    NASA Astrophysics Data System (ADS)

    Wang, C.; Gordon, R. G.; Zheng, L.

    2015-12-01

    Hotspot tracks have been widely used to estimate the velocities of the plate relative to the lower mantle. Here we analyze the hotspot azimuth data set of Morgan and Phipps Morgan [2007] and show that the errors in plate velocity azimuths inferred from hotspot tracks in any one plate are correlated with the errors of other azimuths in the same plate. We use a two-tier analysis to account for this correlated error. First, we determine an individual best-fitting pole for each plate. Second, we determine the absolute plate velocity by minimizing the misfit while constrained by the MORVEL relative plate velocities [DeMets et al. 2010]. Our preferred model, HS4-MORVEL, uses azimuths from 9 major plates, which are weighted equally. We find that the Pacific plate rotates 0.860.016°Ma-1 right handed about 63.3°S, 96.1°E. Angular velocities of four plates (Amur, Eurasia, Yangtze and Antarctic) differ insignificantly from zero. The net rotation of the lithosphere is 0.24°±0.014° Ma-1 right handed about 52.3S, 56.9E. The angular velocities differ insignificantly from the absolute angular velocities inferred from the orientation of seismic anisotropy [Zheng et al. 2014]. The within-plate dispersion of hotspot track azimuths is 14°, which is comparable to the within-plate dispersion found from orientations of seismic anisotropy. The between-plate dispersion is 6.9±2.4° (95% confidence limits), which is smaller than that found from seismic anisotropy. The between-plate dispersion of 4.5° to 9.3° can be used to place bounds on how fast hotspots under one plate move relative to hotspots under another plate. For an average plate absolute speed of ≈50 mm/yr, the between-plate dispersion indicates a rate of motion of 4 mm/yr to 8 mm/yr for the component of hotspot motion perpendicular to plate motion. This upper bound is consistent with prior work that indicated upper bounds on motion between Pacific hotspots and Indo-Atlantic hotspots over the past 48 Ma of 8-13 mm

  4. Combined CDF and D0 upper limits on MSSM Higgs boson production in tau-tau final states with up to 2.2 fb-1

    SciTech Connect

    Benjamin, Doug; Herndon, Matt; James, Eric; Junk, Tom; Krumnack, Nils; Yao, Weiming; Davies, Gavin; Hays, Jonathan; Adams, Todd; Verdier, Patrice; Fisher, Wade

    2010-03-01

    Combined results are presented on the search for a neutral Higgs boson in the di-tau final state using 1.8 fb{sup -1} and 2.2 fb{sup -1} of integrated luminosity collected at the CDF and D0 experiments respectively. Data were collected in p{bar p} collisions at a centre of mass energy of 1.96 TeV during RunII of the Tevatron. Limits are set on the cross section x branching ratio ranging from 13.6 pb to 0.653 pb for Higgs masses from 90 GeV to 200 GeV respectively. The results are then interpreted as limits in four different benchmark scenarios within the framework of the MSSM.

  5. At the edge of the thermal window: effects of elevated temperature on the resting metabolism, hypoxia tolerance and upper critical thermal limit of a widespread African cichlid

    PubMed Central

    McDonnell, Laura H.; Chapman, Lauren J.

    2015-01-01

    Tropical inland fishes are predicted to be especially vulnerable to thermal stress because they experience small temperature fluctuations that may select for narrow thermal windows. In this study, we measured resting metabolic rate (RMR), critical oxygen tension (Pcrit) and critical thermal maximum (CTMax) of the widespread African cichlid (Pseudocrenilabrus multicolor victoriae) in response to short-term acclimation to temperatures within and above their natural thermal range. Pseudocrenilabrus multicolor collected in Lake Kayanja, Uganda, a population living near the upper thermal range of the species, were acclimated to 23, 26, 29 and 32°C for 3 days directly after capture, and RMR and Pcrit were then quantified. In a second group of P. multicolor from the same population, CTMax and the thermal onset of agitation were determined for fish acclimated to 26, 29 and 32°C for 7 days. Both RMR and Pcrit were significantly higher in fish acclimated to 32°C, indicating decreased tolerance to hypoxia and increased metabolic requirements at temperatures only slightly (∼1°C) above their natural thermal range. The CTMax increased with acclimation temperature, indicating some degree of thermal compensation induced by short-term exposure to higher temperatures. However, agitation temperature (likely to represent an avoidance response to increased temperature during CTMax trials) showed no increase with acclimation temperature. Overall, the results of this study demonstrate that P. multicolor is able to maintain its RMR and Pcrit across the range of temperatures characteristic of its natural habitat, but incurs a higher cost of resting metabolism and reduced hypoxia tolerance at temperatures slightly above its present range. PMID:27293734

  6. Cosmology with negative absolute temperatures

    NASA Astrophysics Data System (ADS)

    Vieira, J. P. P.; Byrnes, Christian T.; Lewis, Antony

    2016-08-01

    Negative absolute temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al. [1] has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion (w < ‑1) with no Big Rip, and their contracting counterparts are forced to bounce after the energy density becomes sufficiently large. Both scenarios might be used to solve horizon and flatness problems analogously to standard inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum.

  7. Apparatus for absolute pressure measurement

    NASA Technical Reports Server (NTRS)

    Hecht, R. (Inventor)

    1969-01-01

    An absolute pressure sensor (e.g., the diaphragm of a capacitance manometer) was subjected to a superimposed potential to effectively reduce the mechanical stiffness of the sensor. This substantially increases the sensitivity of the sensor and is particularly useful in vacuum gauges. An oscillating component of the superimposed potential induced vibrations of the sensor. The phase of these vibrations with respect to that of the oscillating component was monitored, and served to initiate an automatic adjustment of the static component of the superimposed potential, so as to bring the sensor into resonance at the frequency of the oscillating component. This establishes a selected sensitivity for the sensor, since a definite relationship exists between resonant frequency and sensitivity.

  8. Cosmology with negative absolute temperatures

    NASA Astrophysics Data System (ADS)

    Vieira, J. P. P.; Byrnes, Christian T.; Lewis, Antony

    2016-08-01

    Negative absolute temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al. [1] has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion (w < -1) with no Big Rip, and their contracting counterparts are forced to bounce after the energy density becomes sufficiently large. Both scenarios might be used to solve horizon and flatness problems analogously to standard inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum.

  9. Absolute photon-flux measurements in the vacuum ultraviolet

    NASA Technical Reports Server (NTRS)

    Samson, J. A. R.; Haddad, G. N.

    1974-01-01

    Absolute photon-flux measurements in the vacuum ultraviolet have extended to short wavelengths by use of rare-gas ionization chambers. The technique involves the measurement of the ion current as a function of the gas pressure in the ion chamber. The true value of the ion current, and hence the absolute photon flux, is obtained by extrapolating the ion current to zero gas pressure. Examples are given at 162 and 266 A. The short-wavelength limit is determined only by the sensitivity of the current-measuring apparatus and by present knowledge of the photoionization processes that occur in the rate gases.

  10. Measurement of the Absolute Branching Fractions of$B^\\pm \\to K^\\pm X_{c\\bar c}$

    SciTech Connect

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Tisserand, V.; Zghiche, A.; Grauges, E.; Palano, A.; Pappagallo, M.; Pompili, A.; Chen, J.C.; Qi, N.D.; Rong, G.; Wang, P.; Zhu, Y.S.; Eigen, G.; Ofte, I.; Stugu, B. /Bergen U. /LBL, Berkeley /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /INFN, Ferrara /Frascati /Genoa U. /INFN, Genoa /Harvard U. /Heidelberg U. /Karlsruhe U., EKP /Imperial Coll., London /Iowa U. /Iowa State U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /INFN, Naples /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /INFN, Padua /Paris U., VI-VII /Pennsylvania U. /Perugia U. /INFN, Perugia /Pisa U. /INFN, Pisa /Prairie View A-M /Princeton U. /Rome U. /INFN, Rome /Rostock U. /Rutherford /DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Stony Brook /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /INFN, Turin /Trieste U. /INFN, Trieste /Valencia U., IFIC /Vanderbilt U. /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U. /Basilicata U., Potenza

    2005-11-02

    We study the two-body decays of B{sup {+-}} mesons to K{sup {+-}} and a charmonium state, X{sub c{bar c}}, in a sample of 210.5 fb{sup -1} of data from the BABAR experiment. We perform measurements of absolute branching fractions {Beta}(B{sup {+-}} {yields} K{sup {+-}} X{sub c{bar c}}) using a missing mass technique, and report several new or improved results. In particular, the upper limit {Beta}(B{sup {+-}} {yields} K{sup {+-}}(3872)) < 3.2 x 10{sup -4} at 90% CL and the inferred lower limit {Beta}(X(3872) {yields} J/{psi}{pi}{sup +}{pi}{sup -}) > 4.2% will help in understanding the nature of the recently discovered X(3872).

  11. Water purification and the incidence of fractures in patients receiving home haemodialysis supervised by a single centre: evidence for "safe" upper limit of aluminium in water.

    PubMed Central

    Platts, M M; Owen, G; Smith, S

    1984-01-01

    Between 1968 and 1980 fractures occurred in 56 of 284 patients treated by home haemodialysis in the Sheffield area for longer than one year. Patients sustained four times as many fractures while using dialysate prepared with water containing more than 1.0 mumol aluminium per 1 (2.7 micrograms/100 ml) than while using water containing a smaller concentration. When aluminium was removed from water by deionisation the incidence of fractures diminished during the next year and no patient developed dialysis encephalopathy. These findings show that 1.0 mumol/l is a safe maximum concentration of aluminium in water for use in home haemodialysis. It can be detected by the colorimetric aluminium analyses used by many water authorities. When financial resources are limited it is expedient to reserve aluminium analyses by electrothermal atomic absorption for plasma from patients receiving regular haemodialysis. Ingestion of aluminium hydroxide contributes significantly to the increased plasma aluminium concentration of these patients. PMID:6423163

  12. The application scope of the reductive perturbation method and the upper limit of the dust acoustic solitary waves in a dusty plasma

    SciTech Connect

    Qi, Xin; Xu, Yan-xia; Duan, Wen-shan; Yang, Lei

    2014-01-15

    The dust acoustic solitary waves have been numerically investigated by using one dimensional electrostatic particle-in-cell method. By comparing the numerical results with those obtained from the traditional reductive perturbation method, it is found that there exist the maximum dimensionless amplitude and propagation speed of the dust acoustic solitary wave. And these limitations of the solitary wave are explained by using the Sagdeev potential technique. Furthermore, it is noticed that although ϵ ≪ 1 is required in the reductive perturbation method generally, the reductive perturbation method is also valid for ϵ < 1 in a dusty plasma, which may be extended to branches where the reductive perturbation method is used.

  13. SALT Long-slit Spectroscopy of Luminous Obscured Quasars: An Upper Limit on the Size of the Narrow-line Region?

    NASA Astrophysics Data System (ADS)

    Hainline, Kevin N.; Hickox, Ryan; Greene, Jenny E.; Myers, Adam D.; Zakamska, Nadia L.

    2013-09-01

    We present spatially resolved long-slit spectroscopy from the Southern African Large Telescope to examine the spatial extent of the narrow-line regions (NLRs) of a sample of eight luminous obscured quasars at 0.10 < z < 0.43. Our results are consistent with an observed shallow slope in the relationship between NLR size and L [O III], which has been interpreted to indicate that NLR size is limited by the density and ionization state of the NLR gas rather than the availability of ionizing photons. We also explore how the NLR size scales with a more direct measure of instantaneous active galactic nucleus power using mid-IR photometry from the Wide Field Infrared Explorer, which probes warm to hot dust near the central black hole and so, unlike [O III], does not depend on the properties of the NLR. Using our results as well as samples from the literature, we obtain a power-law relationship between NLR size and L 8 μm that is significantly steeper than that observed for NLR size and L [O III]. We find that the size of the NLR goes approximately as L^{1/2}_{8\\,\\mu {m}}, as expected from the simple scenario of constant-density clouds illuminated by a central ionizing source. We further see tentative evidence for a flattening of the relationship between NLR size and L 8 μm at the high-luminosity end, and propose that we are seeing a limiting NLR size of 10-20 kpc, beyond which the availability of gas to ionize becomes too low. We find that L_{[{O\\,{\\scriptsize {III}}}]} \\sim L_{8 \\,\\mu {m}}^{1.4}, consistent with a picture in which the L [O III] is dependent on the volume of the NLR. These results indicate that high-luminosity quasars have a strong effect in ionizing the available gas in a galaxy.

  14. SALT LONG-SLIT SPECTROSCOPY OF LUMINOUS OBSCURED QUASARS: AN UPPER LIMIT ON THE SIZE OF THE NARROW-LINE REGION?

    SciTech Connect

    Hainline, Kevin N.; Hickox, Ryan; Greene, Jenny E.; Myers, Adam D.; Zakamska, Nadia L.

    2013-09-10

    We present spatially resolved long-slit spectroscopy from the Southern African Large Telescope to examine the spatial extent of the narrow-line regions (NLRs) of a sample of eight luminous obscured quasars at 0.10 < z < 0.43. Our results are consistent with an observed shallow slope in the relationship between NLR size and L{sub [OIII]}, which has been interpreted to indicate that NLR size is limited by the density and ionization state of the NLR gas rather than the availability of ionizing photons. We also explore how the NLR size scales with a more direct measure of instantaneous active galactic nucleus power using mid-IR photometry from the Wide Field Infrared Explorer, which probes warm to hot dust near the central black hole and so, unlike [O III], does not depend on the properties of the NLR. Using our results as well as samples from the literature, we obtain a power-law relationship between NLR size and L{sub 8{mu}m} that is significantly steeper than that observed for NLR size and L{sub [OIII]}. We find that the size of the NLR goes approximately as L{sup 1/2}{sub 8{mu}m}, as expected from the simple scenario of constant-density clouds illuminated by a central ionizing source. We further see tentative evidence for a flattening of the relationship between NLR size and L{sub 8{mu}m} at the high-luminosity end, and propose that we are seeing a limiting NLR size of 10-20 kpc, beyond which the availability of gas to ionize becomes too low. We find that L{sub [OIII]}{approx}L{sub 8{mu}m}{sup 1.4}, consistent with a picture in which the L{sub [OIII]} is dependent on the volume of the NLR. These results indicate that high-luminosity quasars have a strong effect in ionizing the available gas in a galaxy.

  15. A global pharmaceutical company initiative: an evidence-based approach to define the upper limit of body weight loss in short term toxicity studies.

    PubMed

    Chapman, Kathryn; Sewell, Fiona; Allais, Linda; Delongeas, Jean-Luc; Donald, Elizabeth; Festag, Matthias; Kervyn, Sophie; Ockert, Deborah; Nogues, Vicente; Palmer, Helen; Popovic, Marija; Roosen, Wendy; Schoenmakers, Ankie; Somers, Kevin; Stark, Claudia; Stei, Peter; Robinson, Sally

    2013-10-01

    Short term toxicity studies are conducted in animals to provide information on major adverse effects typically at the maximum tolerated dose (MTD). Such studies are important from a scientific and ethical perspective as they are used to make decisions on progression of potential candidate drugs, and to set dose levels for subsequent regulatory studies. The MTD is usually determined by parameters such as clinical signs, reductions in body weight and food consumption. However, these assessments are often subjective and there are no published criteria to guide the selection of an appropriate MTD. Even where an objective measurement exists, such as body weight loss (BWL), there is no agreement on what level constitutes an MTD. A global initiative including 15 companies, led by the National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), has shared data on BWL in toxicity studies to assess the impact on the animal and the study outcome. Information on 151 studies has been used to develop an alert/warning system for BWL in short term toxicity studies. The data analysis supports BWL limits for short term dosing (up to 7days) of 10% for rat and dog and 6% for non-human primates (NHPs).

  16. Absolute configuration of isovouacapenol C

    PubMed Central

    Fun, Hoong-Kun; Yodsaoue, Orapun; Karalai, Chatchanok; Chantrapromma, Suchada

    2010-01-01

    The title compound, C27H34O5 {systematic name: (4aR,5R,6R,6aS,7R,11aS,11bR)-4a,6-dihy­droxy-4,4,7,11b-tetra­methyl-1,2,3,4,4a,5,6,6a,7,11,11a,11b-dodeca­hydro­phenanthro[3,2-b]furan-5-yl benzoate}, is a cassane furan­oditerpene, which was isolated from the roots of Caesalpinia pulcherrima. The three cyclo­hexane rings are trans fused: two of these are in chair conformations with the third in a twisted half-chair conformation, whereas the furan ring is almost planar (r.m.s. deviation = 0.003 Å). An intra­molecular C—H⋯O inter­action generates an S(6) ring. The absolute configurations of the stereogenic centres at positions 4a, 5, 6, 6a, 7, 11a and 11b are R, R, R, S, R, S and R, respectively. In the crystal, mol­ecules are linked into infinite chains along [010] by O—H⋯O hydrogen bonds. C⋯O [3.306 (2)–3.347 (2) Å] short contacts and C—H⋯π inter­actions also occur. PMID:21588364

  17. Effect of acclimation temperature on the upper thermal tolerance of Colorado River cutthroat trout Oncorhynchus clarkii pleuriticus: thermal limits of a North American salmonid.

    PubMed

    Underwood, Z E; Myrick, C A; Rogers, K B

    2012-06-01

    In an effort to explore the thermal limitations of Colorado River cutthroat trout Oncorhynchus clarkii pleuriticus, the critical thermal maxima (T(cmax) ) of 1+ year Lake Nanita strain O. c. pleuriticus were evaluated when acclimated to 10, 15 and 20° C. The mean ±s.d.T(cmax) for O. c. pleuriticus acclimated to 10° C was 24·6 ± 2·0°C (n = 30), for 15° C-acclimated fish was 26·9 ± 1·5° C (n = 23) and for 20° C-acclimated fish was 29·4 ± 1·1° C (n = 28); these results showed a marked thermal acclimation effect (Q₁₀ = 1·20). Interestingly, there was a size effect within treatments, wherein the T(cmax) of larger fish was significantly lower than that of smaller fish acclimated to the same temperature. The critical thermal tolerances of age 0 year O. c. pleuriticus were also evaluated from three separate populations: Lake Nanita, Trapper Creek and Carr Creek reared under 'common-garden' conditions prior to thermal acclimation. The Trapper Creek population had significantly warmer T(cmax) than the Lake Nanita population, but that of the Carr Creek fish had T(cmax) similar to both Trapper Creek and Lake Nanita fish. A comparison of these O. c. pleuriticus T(cmax) results with those of other stream-dwelling salmonids suggested that O. c. pleuriticus are less resistant to rapid thermal fluctuations when acclimated to cold temperatures, but can tolerate similar temperatures when acclimated to warmer temperatures. PMID:22650425

  18. Frequency-domain analysis of absolute gravimeters

    NASA Astrophysics Data System (ADS)

    Svitlov, S.

    2012-12-01

    An absolute gravimeter is analysed as a linear time-invariant system in the frequency domain. Frequency responses of absolute gravimeters are derived analytically based on the propagation of the complex exponential signal through their linear measurement functions. Depending on the model of motion and the number of time-distance coordinates, an absolute gravimeter is considered as a second-order (three-level scheme) or third-order (multiple-level scheme) low-pass filter. It is shown that the behaviour of an atom absolute gravimeter in the frequency domain corresponds to that of the three-level corner-cube absolute gravimeter. Theoretical results are applied for evaluation of random and systematic measurement errors and optimization of an experiment. The developed theory agrees with known results of an absolute gravimeter analysis in the time and frequency domains and can be used for measurement uncertainty analyses, building of vibration-isolation systems and synthesis of digital filtering algorithms.

  19. Absolute Income, Relative Income, and Happiness

    ERIC Educational Resources Information Center

    Ball, Richard; Chernova, Kateryna

    2008-01-01

    This paper uses data from the World Values Survey to investigate how an individual's self-reported happiness is related to (i) the level of her income in absolute terms, and (ii) the level of her income relative to other people in her country. The main findings are that (i) both absolute and relative income are positively and significantly…

  20. Investigating Absolute Value: A Real World Application

    ERIC Educational Resources Information Center

    Kidd, Margaret; Pagni, David

    2009-01-01

    Making connections between various representations is important in mathematics. In this article, the authors discuss the numeric, algebraic, and graphical representations of sums of absolute values of linear functions. The initial explanations are accessible to all students who have experience graphing and who understand that absolute value simply…

  1. Preschoolers' Success at Coding Absolute Size Values.

    ERIC Educational Resources Information Center

    Russell, James

    1980-01-01

    Forty-five 2-year-old and forty-five 3-year-old children coded relative and absolute sizes using 1.5-inch, 6-inch, and 18-inch cardboard squares. Results indicate that absolute coding is possible for children of this age. (Author/RH)

  2. Introducing the Mean Absolute Deviation "Effect" Size

    ERIC Educational Resources Information Center

    Gorard, Stephen

    2015-01-01

    This paper revisits the use of effect sizes in the analysis of experimental and similar results, and reminds readers of the relative advantages of the mean absolute deviation as a measure of variation, as opposed to the more complex standard deviation. The mean absolute deviation is easier to use and understand, and more tolerant of extreme…

  3. Monolithically integrated absolute frequency comb laser system

    DOEpatents

    Wanke, Michael C.

    2016-07-12

    Rather than down-convert optical frequencies, a QCL laser system directly generates a THz frequency comb in a compact monolithically integrated chip that can be locked to an absolute frequency without the need of a frequency-comb synthesizer. The monolithic, absolute frequency comb can provide a THz frequency reference and tool for high-resolution broad band spectroscopy.

  4. Estimating the absolute wealth of households

    PubMed Central

    Gerkey, Drew; Hadley, Craig

    2015-01-01

    Abstract Objective To estimate the absolute wealth of households using data from demographic and health surveys. Methods We developed a new metric, the absolute wealth estimate, based on the rank of each surveyed household according to its material assets and the assumed shape of the distribution of wealth among surveyed households. Using data from 156 demographic and health surveys in 66 countries, we calculated absolute wealth estimates for households. We validated the method by comparing the proportion of households defined as poor using our estimates with published World Bank poverty headcounts. We also compared the accuracy of absolute versus relative wealth estimates for the prediction of anthropometric measures. Findings The median absolute wealth estimates of 1 403 186 households were 2056 international dollars per capita (interquartile range: 723–6103). The proportion of poor households based on absolute wealth estimates were strongly correlated with World Bank estimates of populations living on less than 2.00 United States dollars per capita per day (R2 = 0.84). Absolute wealth estimates were better predictors of anthropometric measures than relative wealth indexes. Conclusion Absolute wealth estimates provide new opportunities for comparative research to assess the effects of economic resources on health and human capital, as well as the long-term health consequences of economic change and inequality. PMID:26170506

  5. Absolute optical metrology : nanometers to kilometers

    NASA Technical Reports Server (NTRS)

    Dubovitsky, Serge; Lay, O. P.; Peters, R. D.; Liebe, C. C.

    2005-01-01

    We provide and overview of the developments in the field of high-accuracy absolute optical metrology with emphasis on space-based applications. Specific work on the Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor is described along with novel applications of the sensor.

  6. Absolute instability of the Gaussian wake profile

    NASA Technical Reports Server (NTRS)

    Hultgren, Lennart S.; Aggarwal, Arun K.

    1987-01-01

    Linear parallel-flow stability theory has been used to investigate the effect of viscosity on the local absolute instability of a family of wake profiles with a Gaussian velocity distribution. The type of local instability, i.e., convective or absolute, is determined by the location of a branch-point singularity with zero group velocity of the complex dispersion relation for the instability waves. The effects of viscosity were found to be weak for values of the wake Reynolds number, based on the center-line velocity defect and the wake half-width, larger than about 400. Absolute instability occurs only for sufficiently large values of the center-line wake defect. The critical value of this parameter increases with decreasing wake Reynolds number, thereby indicating a shrinking region of absolute instability with decreasing wake Reynolds number. If backflow is not allowed, absolute instability does not occur for wake Reynolds numbers smaller than about 38.

  7. Gyrokinetic Statistical Absolute Equilibrium and Turbulence

    SciTech Connect

    Jian-Zhou Zhu and Gregory W. Hammett

    2011-01-10

    A paradigm based on the absolute equilibrium of Galerkin-truncated inviscid systems to aid in understanding turbulence [T.-D. Lee, "On some statistical properties of hydrodynamical and magnetohydrodynamical fields," Q. Appl. Math. 10, 69 (1952)] is taken to study gyrokinetic plasma turbulence: A finite set of Fourier modes of the collisionless gyrokinetic equations are kept and the statistical equilibria are calculated; possible implications for plasma turbulence in various situations are discussed. For the case of two spatial and one velocity dimension, in the calculation with discretization also of velocity v with N grid points (where N + 1 quantities are conserved, corresponding to an energy invariant and N entropy-related invariants), the negative temperature states, corresponding to the condensation of the generalized energy into the lowest modes, are found. This indicates a generic feature of inverse energy cascade. Comparisons are made with some classical results, such as those of Charney-Hasegawa-Mima in the cold-ion limit. There is a universal shape for statistical equilibrium of gyrokinetics in three spatial and two velocity dimensions with just one conserved quantity. Possible physical relevance to turbulence, such as ITG zonal flows, and to a critical balance hypothesis are also discussed.

  8. Diagnostic Application of Absolute Neutron Activation Analysis in Hematology

    SciTech Connect

    Zamboni, C.B.; Oliveira, L.C.; Dalaqua, L. Jr.

    2004-10-03

    The Absolute Neutron Activation Analysis (ANAA) technique was used to determine element concentrations of Cl and Na in blood of healthy group (male and female blood donators), select from Blood Banks at Sao Paulo city, to provide information which can help in diagnosis of patients. This study permitted to perform a discussion about the advantages and limitations of using this nuclear methodology in hematological examinations.

  9. Observables sensitive to absolute neutrino masses: Constraints and correlations from world neutrino data

    SciTech Connect

    Fogli, G.L.; Lisi, E.; Marrone, A.; Palazzo, A.; Melchiorri, A.; Serra, P.; Silk, J.

    2004-12-01

    In the context of three-flavor neutrino mixing, we present a thorough study of the phenomenological constraints applicable to three observables sensitive to absolute neutrino masses: The effective neutrino mass in Tritium beta-decay (m{sub {beta}}); the effective Majorana neutrino mass in neutrinoless double beta-decay (m{sub {beta}}{sub {beta}}); and the sum of neutrino masses in cosmology ({sigma}). We discuss the correlations among these variables which arise from the combination of all the available neutrino oscillation data, in both normal and inverse neutrino mass hierarchy. We set upper limits on m{sub {beta}} by combining updated results from the Mainz and Troitsk experiments. We also consider the latest results on m{sub {beta}}{sub {beta}} from the Heidelberg-Moscow experiment, both with and without the lower bound claimed by such experiment. We derive upper limits on {sigma} from an updated combination of data from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite and the two degrees Fields (2dF) Galaxy Redshifts Survey, with and without Lyman-{alpha} forest data from the Sloan Digital Sky Survey (SDSS), in models with a nonzero running of the spectral index of primordial inflationary perturbations. The results are discussed in terms of two-dimensional projections of the globally allowed region in the (m{sub {beta}},m{sub {beta}}{sub {beta}},{sigma}) parameter space, which neatly show the relative impact of each data set. In particular, the (in)compatibility between {sigma} and m{sub {beta}}{sub {beta}} constraints is highlighted for various combinations of data. We also briefly discuss how future neutrino data (both oscillatory and nonoscillatory) can further probe the currently allowed regions.

  10. The sulfur depletion problem: upper limits on the H2S2, HS·2, and S2 gas-phase abundances toward the low-mass warm core IRAS 16293-2422

    NASA Astrophysics Data System (ADS)

    Martín-Doménech, R.; Jiménez-Serra, I.; Muñoz Caro, G. M.; Müller, H. S. P.; Occhiogrosso, A.; Testi, L.; Woods, P. M.; Viti, S.

    2016-01-01

    Context. A fraction of the missing sulfur in dense clouds and circumstellar regions could be in the form of three species not yet detected in the interstellar medium: H2S2, HS.2, and S2 according to experimental simulations performed under astrophysically relevant conditions. These S-S bonded molecules can be formed by the energetic processing of H2S-bearing ice mantles on dust grains, and subsequently desorb to the gas phase. Aims: The detection of these species could partially solve the sulfur depletion problem, and would help to improve our knowledge of the poorly known chemistry of sulfur in the interstellar medium. To this purpose we calculated the frequencies and expected intensities of the rotational transitions not previously reported, and performed dedicated ground-based observations toward the low-mass warm core IRAS 16293-2422, a region with one of the highest measured gas-phase H2S abundances. Methods: Observations in the submillimeter regime were obtained with the APEX 12 m telescope during 15 h of observation. A total of ~16 GHz were covered in a range of about 100 GHz, targeting a wide selection of the predicted rotational transitions of the three molecules. Results: The 1σ noise rms values were extracted in the spectral regions where the targeted species should have been detected. These values were a factor of 2-7 lower than those reached by previous observations toward the same source, and allowed us to estimate a 1σ upper limit to their molecular abundances of ≤8.1 × 10-9, ≤ 1.1 × 10-8, and ≤ 2.9 × 10-7 relative to H2, for H2S 2 , HS.2, and S2, respectively. Conclusions: The upper limit abundances of the three molecules containing the S2 unit are up to two orders of magnitude lower than the H2S abundance in the source, and one order of magnitude lower than the expected abundances from the experimental simulations using ice analogs. Subsequent gas-phase chemistry after desorption could lower the abundances of the three species to

  11. Absolute magnitudes of trans-neptunian objects

    NASA Astrophysics Data System (ADS)

    Duffard, R.; Alvarez-candal, A.; Pinilla-Alonso, N.; Ortiz, J. L.; Morales, N.; Santos-Sanz, P.; Thirouin, A.

    2015-10-01

    Accurate measurements of diameters of trans- Neptunian objects are extremely complicated to obtain. Radiomatric techniques applied to thermal measurements can provide good results, but precise absolute magnitudes are needed to constrain diameters and albedos. Our objective is to measure accurate absolute magnitudes for a sample of trans- Neptunian objects, many of which have been observed, and modelled, by the "TNOs are cool" team, one of Herschel Space Observatory key projects grantes with ~ 400 hours of observing time. We observed 56 objects in filters V and R, if possible. These data, along with data available in the literature, was used to obtain phase curves and to measure absolute magnitudes by assuming a linear trend of the phase curves and considering magnitude variability due to rotational light-curve. In total we obtained 234 new magnitudes for the 56 objects, 6 of them with no reported previous measurements. Including the data from the literature we report a total of 109 absolute magnitudes.

  12. A New Gimmick for Assigning Absolute Configuration.

    ERIC Educational Resources Information Center

    Ayorinde, F. O.

    1983-01-01

    A five-step procedure is provided to help students in making the assignment absolute configuration less bothersome. Examples for both single (2-butanol) and multi-chiral carbon (3-chloro-2-butanol) molecules are included. (JN)

  13. The Simplicity Argument and Absolute Morality

    ERIC Educational Resources Information Center

    Mijuskovic, Ben

    1975-01-01

    In this paper the author has maintained that there is a similarity of thought to be found in the writings of Cudworth, Emerson, and Husserl in his investigation of an absolute system of morality. (Author/RK)

  14. Absolute Plate Velocities from Seismic Anisotropy

    NASA Astrophysics Data System (ADS)

    Kreemer, Corné; Zheng, Lin; Gordon, Richard

    2015-04-01

    The orientation of seismic anisotropy inferred beneath plate interiors may provide a means to estimate the motions of the plate relative to the sub-asthenospheric mantle. Here we analyze two global sets of shear-wave splitting data, that of Kreemer [2009] and an updated and expanded data set, to estimate plate motions and to better understand the dispersion of the data, correlations in the errors, and their relation to plate speed. We also explore the effect of using geologically current plate velocities (i.e., the MORVEL set of angular velocities [DeMets et al. 2010]) compared with geodetically current plate velocities (i.e., the GSRM v1.2 angular velocities [Kreemer et al. 2014]). We demonstrate that the errors in plate motion azimuths inferred from shear-wave splitting beneath any one tectonic plate are correlated with the errors of other azimuths from the same plate. To account for these correlations, we adopt a two-tier analysis: First, find the pole of rotation and confidence limits for each plate individually. Second, solve for the best fit to these poles while constraining relative plate angular velocities to consistency with the MORVEL relative plate angular velocities. The SKS-MORVEL absolute plate angular velocities (based on the Kreemer [2009] data set) are determined from the poles from eight plates weighted proportionally to the root-mean-square velocity of each plate. SKS-MORVEL indicates that eight plates (Amur, Antarctica, Caribbean, Eurasia, Lwandle, Somalia, Sundaland, and Yangtze) have angular velocities that differ insignificantly from zero. The net rotation of the lithosphere is 0.25±0.11° Ma-1 (95% confidence limits) right-handed about 57.1°S, 68.6°E. The within-plate dispersion of seismic anisotropy for oceanic lithosphere (σ=19.2° ) differs insignificantly from that for continental lithosphere (σ=21.6° ). The between-plate dispersion, however, is significantly smaller for oceanic lithosphere (σ=7.4° ) than for continental

  15. Combined CDF and D0 upper limits on $gg\\to H\\to W^+W^-$ and constraints on the Higgs boson mass in fourth-generation fermion models with up to 8.2 fb$^{-1}$ of data

    SciTech Connect

    Benjamin, Doug; /Tufts U.

    2011-08-01

    We combine results from searches by the CDF and D0 Collaborations for a standard model Higgs boson (H) in the processes gg {yields} H {yields} W{sup +}W{sup -} and gg {yields} H {yields} ZZ in p{bar p} collisions at the Fermilab Tevatron Collider at {radical}s = 1.96 TeV. With 8.2 fb{sup -1} of integrated luminosity analyzed at CDF and 8.1 fb{sup -1} at D0, the 95% C.L. upper limit on {sigma}(gg {yields} H) x {Beta}(H {yields} W{sup +}W{sup -}) is 1.01 pb at m{sub H} = 120 GeV, 0.40 pb at m{sub H} = 165 GeV, and 0.47 pb at m{sub H} = 200 GeV. Assuming the presence of a fourth sequential generation of fermions with large masses, we exclude at the 95% Confidence Level a standard-model-like Higgs boson with a mass between 124 and 286 GeV.

  16. Jasminum flexile flower absolute from India--a detailed comparison with three other jasmine absolutes.

    PubMed

    Braun, Norbert A; Kohlenberg, Birgit; Sim, Sherina; Meier, Manfred; Hammerschmidt, Franz-Josef

    2009-09-01

    Jasminum flexile flower absolute from the south of India and the corresponding vacuum headspace (VHS) sample of the absolute were analyzed using GC and GC-MS. Three other commercially available Indian jasmine absolutes from the species: J. sambac, J. officinale subsp. grandiflorum, and J. auriculatum and the respective VHS samples were used for comparison purposes. One hundred and twenty-one compounds were characterized in J. flexile flower absolute, with methyl linolate, benzyl salicylate, benzyl benzoate, (2E,6E)-farnesol, and benzyl acetate as the main constituents. A detailed olfactory evaluation was also performed.

  17. Universal Cosmic Absolute and Modern Science

    NASA Astrophysics Data System (ADS)

    Kostro, Ludwik

    The official Sciences, especially all natural sciences, respect in their researches the principle of methodic naturalism i.e. they consider all phenomena as entirely natural and therefore in their scientific explanations they do never adduce or cite supernatural entities and forces. The purpose of this paper is to show that Modern Science has its own self-existent, self-acting, and self-sufficient Natural All-in Being or Omni-Being i.e. the entire Nature as a Whole that justifies the scientific methodic naturalism. Since this Natural All-in Being is one and only It should be considered as the own scientifically justified Natural Absolute of Science and should be called, in my opinion, the Universal Cosmic Absolute of Modern Science. It will be also shown that the Universal Cosmic Absolute is ontologically enormously stratified and is in its ultimate i.e. in its most fundamental stratum trans-reistic and trans-personal. It means that in its basic stratum. It is neither a Thing or a Person although It contains in Itself all things and persons with all other sentient and conscious individuals as well, On the turn of the 20th century the Science has begun to look for a theory of everything, for a final theory, for a master theory. In my opinion the natural Universal Cosmic Absolute will constitute in such a theory the radical all penetrating Ultimate Basic Reality and will substitute step by step the traditional supernatural personal Absolute.

  18. Systematics and limit calculations

    SciTech Connect

    Fisher, Wade; /Fermilab

    2006-12-01

    This note discusses the estimation of systematic uncertainties and their incorporation into upper limit calculations. Two different approaches to reducing systematics and their degrading impact on upper limits are introduced. An improved {chi}{sup 2} function is defined which is useful in comparing Poisson distributed data with models marginalized by systematic uncertainties. Also, a technique using profile likelihoods is introduced which provides a means of constraining the degrading impact of systematic uncertainties on limit calculations.

  19. Quantum theory allows for absolute maximal contextuality

    NASA Astrophysics Data System (ADS)

    Amaral, Barbara; Cunha, Marcelo Terra; Cabello, Adán

    2015-12-01

    Contextuality is a fundamental feature of quantum theory and a necessary resource for quantum computation and communication. It is therefore important to investigate how large contextuality can be in quantum theory. Linear contextuality witnesses can be expressed as a sum S of n probabilities, and the independence number α and the Tsirelson-like number ϑ of the corresponding exclusivity graph are, respectively, the maximum of S for noncontextual theories and for the theory under consideration. A theory allows for absolute maximal contextuality if it has scenarios in which ϑ /α approaches n . Here we show that quantum theory allows for absolute maximal contextuality despite what is suggested by the examination of the quantum violations of Bell and noncontextuality inequalities considered in the past. Our proof is not constructive and does not single out explicit scenarios. Nevertheless, we identify scenarios in which quantum theory allows for almost-absolute-maximal contextuality.

  20. Absolute calibration in vivo measurement systems

    SciTech Connect

    Kruchten, D.A.; Hickman, D.P.

    1991-02-01

    Lawrence Livermore National Laboratory (LLNL) is currently investigating a new method for obtaining absolute calibration factors for radiation measurement systems used to measure internally deposited radionuclides in vivo. Absolute calibration of in vivo measurement systems will eliminate the need to generate a series of human surrogate structures (i.e., phantoms) for calibrating in vivo measurement systems. The absolute calibration of in vivo measurement systems utilizes magnetic resonance imaging (MRI) to define physiological structure, size, and composition. The MRI image provides a digitized representation of the physiological structure, which allows for any mathematical distribution of radionuclides within the body. Using Monte Carlo transport codes, the emission spectrum from the body is predicted. The in vivo measurement equipment is calibrated using the Monte Carlo code and adjusting for the intrinsic properties of the detection system. The calibration factors are verified using measurements of existing phantoms and previously obtained measurements of human volunteers. 8 refs.

  1. Stimulus probability effects in absolute identification.

    PubMed

    Kent, Christopher; Lamberts, Koen

    2016-05-01

    This study investigated the effect of stimulus presentation probability on accuracy and response times in an absolute identification task. Three schedules of presentation were used to investigate the interaction between presentation probability and stimulus position within the set. Data from individual participants indicated strong effects of presentation probability on both proportion correct and response times. The effects were moderated by the ubiquitous stimulus position effect. The accuracy and response time data were predicted by an exemplar-based model of perceptual cognition (Kent & Lamberts, 2005). The bow in discriminability was also attenuated when presentation probability for middle items was relatively high, an effect that will constrain future model development. The study provides evidence for item-specific learning in absolute identification. Implications for other theories of absolute identification are discussed. (PsycINFO Database Record

  2. Quantitative standards for absolute linguistic universals.

    PubMed

    Piantadosi, Steven T; Gibson, Edward

    2014-01-01

    Absolute linguistic universals are often justified by cross-linguistic analysis: If all observed languages exhibit a property, the property is taken to be a likely universal, perhaps specified in the cognitive or linguistic systems of language learners and users. In many cases, these patterns are then taken to motivate linguistic theory. Here, we show that cross-linguistic analysis will very rarely be able to statistically justify absolute, inviolable patterns in language. We formalize two statistical methods--frequentist and Bayesian--and show that in both it is possible to find strict linguistic universals, but that the numbers of independent languages necessary to do so is generally unachievable. This suggests that methods other than typological statistics are necessary to establish absolute properties of human language, and thus that many of the purported universals in linguistics have not received sufficient empirical justification.

  3. Absolute photoacoustic thermometry in deep tissue.

    PubMed

    Yao, Junjie; Ke, Haixin; Tai, Stephen; Zhou, Yong; Wang, Lihong V

    2013-12-15

    Photoacoustic thermography is a promising tool for temperature measurement in deep tissue. Here we propose an absolute temperature measurement method based on the dual temperature dependences of the Grüneisen parameter and the speed of sound in tissue. By taking ratiometric measurements at two adjacent temperatures, we can eliminate the factors that are temperature irrelevant but difficult to correct for in deep tissue. To validate our method, absolute temperatures of blood-filled tubes embedded ~9 mm deep in chicken tissue were measured in a biologically relevant range from 28°C to 46°C. The temperature measurement accuracy was ~0.6°C. The results suggest that our method can be potentially used for absolute temperature monitoring in deep tissue during thermotherapy.

  4. Molecular iodine absolute frequencies. Final report

    SciTech Connect

    Sansonetti, C.J.

    1990-06-25

    Fifty specified lines of {sup 127}I{sub 2} were studied by Doppler-free frequency modulation spectroscopy. For each line the classification of the molecular transition was determined, hyperfine components were identified, and one well-resolved component was selected for precise determination of its absolute frequency. In 3 cases, a nearby alternate line was selected for measurement because no well-resolved component was found for the specified line. Absolute frequency determinations were made with an estimated uncertainty of 1.1 MHz by locking a dye laser to the selected hyperfine component and measuring its wave number with a high-precision Fabry-Perot wavemeter. For each line results of the absolute measurement, the line classification, and a Doppler-free spectrum are given.

  5. Direct and Absolute Quantification of over 1800 Yeast Proteins via Selected Reaction Monitoring*

    PubMed Central

    Lawless, Craig; Holman, Stephen W.; Brownridge, Philip; Lanthaler, Karin; Harman, Victoria M.; Watkins, Rachel; Hammond, Dean E.; Miller, Rebecca L.; Sims, Paul F. G.; Grant, Christopher M.; Eyers, Claire E.; Beynon, Robert J.

    2016-01-01

    Defining intracellular protein concentration is critical in molecular systems biology. Although strategies for determining relative protein changes are available, defining robust absolute values in copies per cell has proven significantly more challenging. Here we present a reference data set quantifying over 1800 Saccharomyces cerevisiae proteins by direct means using protein-specific stable-isotope labeled internal standards and selected reaction monitoring (SRM) mass spectrometry, far exceeding any previous study. This was achieved by careful design of over 100 QconCAT recombinant proteins as standards, defining 1167 proteins in terms of copies per cell and upper limits on a further 668, with robust CVs routinely less than 20%. The selected reaction monitoring-derived proteome is compared with existing quantitative data sets, highlighting the disparities between methodologies. Coupled with a quantification of the transcriptome by RNA-seq taken from the same cells, these data support revised estimates of several fundamental molecular parameters: a total protein count of ∼100 million molecules-per-cell, a median of ∼1000 proteins-per-transcript, and a linear model of protein translation explaining 70% of the variance in translation rate. This work contributes a “gold-standard” reference yeast proteome (including 532 values based on high quality, dual peptide quantification) that can be widely used in systems models and for other comparative studies. PMID:26750110

  6. Absolute calibration of space-resolving soft X-ray spectrograph for plasma diagnostics

    NASA Astrophysics Data System (ADS)

    Yoshikawa, M.; Okamoto, Y.; Kawamori, E.; Watanabe, Y.; Watabe, C.; Yamaguchi, N.; Tamano, T.

    2001-07-01

    A grazing incidence flat-field soft X-ray (20-350 Å) spectrograph was constructed and applied for impurity diagnostics in the GAMMA 10 fusion plasma. The spectrograph consisted of a limited height entrance slit, an aberration-corrected concave grating, a microchannel-plate intensified detector and an instant camera/a high speed solid state camera. An absolute calibration experiment for the SX spectrograph was performed at the Photon Factory in the High Energy Accelerator Research Organization with monitoring the incident synchrotron beam intensity by using an absolutely calibrated XUV silicon photodiode. From the results of absolute calibration of the spectrograph, the radiation loss from the plasma was obtained.

  7. Absolute Stability And Hyperstability In Hilbert Space

    NASA Technical Reports Server (NTRS)

    Wen, John Ting-Yung

    1989-01-01

    Theorems on stabilities of feedback control systems proved. Paper presents recent developments regarding theorems of absolute stability and hyperstability of feedforward-and-feedback control system. Theorems applied in analysis of nonlinear, adaptive, and robust control. Extended to provide sufficient conditions for stability in system including nonlinear feedback subsystem and linear time-invariant (LTI) feedforward subsystem, state space of which is Hilbert space, and input and output spaces having finite numbers of dimensions. (In case of absolute stability, feedback subsystem memoryless and possibly time varying. For hyperstability, feedback system dynamical system.)

  8. An Absolute Measurement of Resonance-Resolved Electron Impact Excitation

    NASA Astrophysics Data System (ADS)

    Reisenfeld, Daniel Brett

    1998-11-01

    An experiment to measure electron-impact excitation (EIE) of multiply-charged ions is described. An absolute measurement has been carried out of the cross section for EIE of Si2+(3s2/ 1S/to3s3p/ 1P) from energies below threshold to 11 eV above. A beams modulation technique with inclined electron and ion beams was used. Radiation at 120.7 nm from the excited ions was detected using an absolutely calibrated optical system. The analysis of the experimental data requires a determination of the population fraction of the Si2+ (3s3p/ 3Po) metastable state in the incident ion beam, which was measured to be 0.210 ± 0.018. The data have been corrected for contributions to the signal from radiative decay following excitation from the metastable state to 3s3p1P and 3p2/ 3P, and excitation of the ground state to levels above 3s3p/ 1P. The experimental 0.56 ± 0.08 eV energy spread has allowed us to resolve complex resonance structure throughout the studied energy range. At the reported ±14% uncertainty level (90% confidence limit), the measured structure and absolute scale of the cross section are in good agreement with 12-state close-coupling R-matrix calculations.

  9. CONTROLLING ABSOLUTE FREQUENCY OF FEEDBACK IN A SELF-CONTROLLED SITUATION ENHANCES MOTOR LEARNING.

    PubMed

    Tsai, Min-Jen; Jwo, Hank

    2015-12-01

    The guidance hypothesis suggested that excessive extrinsic feedback facilitates motor performance but blocks the processing of intrinsic information. The present study tested the tenet of guidance hypothesis in self-controlled feedback by controlling the feedback frequency. The motor learning effect of limiting absolute feedback frequency was examined. Thirty-six participants (25 men, 11 women; M age=25.1 yr., SD=2.2) practiced a hand-grip force control task on a dynamometer by the non-dominant hand with varying amounts of feedback. They were randomly assigned to: (a) Self-controlled, (b) Yoked with self-controlled, and (c) Limited self-controlled conditions. In acquisition, two-way analysis of variance indicated significantly lower absolute error in both the yoked and limited self-controlled groups than the self-controlled group. The effect size of absolute error between trials with feedback and without feedback in the limited self-controlled condition was larger than that of the self-controlled condition. In the retention and transfer tests, the Limited self-controlled feedback group had significantly lower absolute error than the other two groups. The results indicated an increased motor learning effect of limiting absolute frequency of feedback in the self-controlled condition.

  10. Acute upper airway infections.

    PubMed

    West, J V

    2002-01-01

    Upper respiratory tract infections are common and important. Although rarely fatal, they are a source of significant morbidity and carry a considerable economic burden. Numerous therapies for the common cold have no effect on symptoms or outcome. Complications such as cough are not improved by over-the-counter preparations, while labelling cough alone as a symptom of asthma may result in unnecessary use of inhaled steroid treatment. Clinical presentation of sore throat does not accurately predict whether the infection is viral or bacterial, while throat culture and rapid antigen tests do not significantly change prescribing practice. Antibiotics have only a limited place in the management of recurrent sore throat due to group A beta-haemolytic streptococcal infection. Routine use of antibiotics in upper respiratory infection enhances parent belief in their effectiveness and increases the likelihood of future consultation in primary care for minor self-limiting illness. Respiratory viruses play a major role in the aetiology of acute otitis media (AOM); prevention includes the use of influenza or RSV vaccination, in addition to reducing other risk factors such as early exposure to respiratory viruses in day-care settings and to environmental tobacco smoke. The use of ventilation tubes (grommets) in secretory otitis media (SOM) remains controversial with conflicting data on developmental outcome and quality of life in young children. New conjugate pneumococcal vaccines appear safe in young children and prevent 6-7% of clinically diagnosed AOM.

  11. Absolute Points for Multiple Assignment Problems

    ERIC Educational Resources Information Center

    Adlakha, V.; Kowalski, K.

    2006-01-01

    An algorithm is presented to solve multiple assignment problems in which a cost is incurred only when an assignment is made at a given cell. The proposed method recursively searches for single/group absolute points to identify cells that must be loaded in any optimal solution. Unlike other methods, the first solution is the optimal solution. The…

  12. Absolute partial photoionization cross sections of ozone.

    SciTech Connect

    Berkowitz, J.; Chemistry

    2008-04-01

    Despite the current concerns about ozone, absolute partial photoionization cross sections for this molecule in the vacuum ultraviolet (valence) region have been unavailable. By eclectic re-evaluation of old/new data and plausible assumptions, such cross sections have been assembled to fill this void.

  13. Stimulus Probability Effects in Absolute Identification

    ERIC Educational Resources Information Center

    Kent, Christopher; Lamberts, Koen

    2016-01-01

    This study investigated the effect of stimulus presentation probability on accuracy and response times in an absolute identification task. Three schedules of presentation were used to investigate the interaction between presentation probability and stimulus position within the set. Data from individual participants indicated strong effects of…

  14. Teaching Absolute Value Inequalities to Mature Students

    ERIC Educational Resources Information Center

    Sierpinska, Anna; Bobos, Georgeana; Pruncut, Andreea

    2011-01-01

    This paper gives an account of a teaching experiment on absolute value inequalities, whose aim was to identify characteristics of an approach that would realize the potential of the topic to develop theoretical thinking in students enrolled in prerequisite mathematics courses at a large, urban North American university. The potential is…

  15. Solving Absolute Value Equations Algebraically and Geometrically

    ERIC Educational Resources Information Center

    Shiyuan, Wei

    2005-01-01

    The way in which students can improve their comprehension by understanding the geometrical meaning of algebraic equations or solving algebraic equation geometrically is described. Students can experiment with the conditions of the absolute value equation presented, for an interesting way to form an overall understanding of the concept.

  16. Absolute Radiometric Calibration Of The Thematic Mapper

    NASA Astrophysics Data System (ADS)

    Slater, P. N.; Biggar, S. F.; Holm, R. G.; Jackson, R. D.; Mao, Y.; Moran, M. S.; Palmer, J. M.; Yuan, B.

    1986-11-01

    The results are presented of five in-flight absolute radiometric calibrations, made in the period July 1984 to November 1985, at White Sands, New Mexico, of the solar reflective bands of the Landsat-5 Thematic Mapper (TM) . The 23 bandcalibrations made on the five dates show a ± 2.8% RMS variation from the mean as a percentage of the mean.

  17. On Relative and Absolute Conviction in Mathematics

    ERIC Educational Resources Information Center

    Weber, Keith; Mejia-Ramos, Juan Pablo

    2015-01-01

    Conviction is a central construct in mathematics education research on justification and proof. In this paper, we claim that it is important to distinguish between absolute conviction and relative conviction. We argue that researchers in mathematics education frequently have not done so and this has lead to researchers making unwarranted claims…

  18. Upper-limb power test in rock-climbing.

    PubMed

    Laffaye, G; Collin, J-M; Levernier, G; Padulo, J

    2014-07-01

    The goal of the present study was to validate a new ecological power-test on athletes of different levels and to assess rock climbers' profiles (boulderers vs. route climbers). 34 athletes divided into novice, skilled and elite groups performed the arm-jump board test (AJ). Power, time, velocity, and efficiency index were recorded. Validity was assessed by comparing the distance with the value extracted from the accelerometer (500 Hz) and the reliability of intra- and inter-session scores. Moreover, a principal component analysis (PCA) was used to assess the climbers' profiles. The AJ test was quite valid, showing a low systematic bias of -0.88 cm (-1.25%) and low limits of agreement (< 6%), and reliable ( Intra-class correlation coefficient = 0.98 and CV < 5%), and was able to distinguish between the 3 samples (p < 0.0001). There was a good correlation between relative upper-limb power (r = 0.70; p < 0.01) and the AJ score. Moreover, the PCA revealed an explosive profile for boulderers and either a weak and quick or slow profile for route climbers, revealing a biomechanical signature of the sub-discipline. The AJ test provides excellent absolute and relative reliabilities for climbing, and can effectively distinguish between climbing athletes of different competitive levels. Thus, the AJ may be suitable for field assessment of upper limb strength in climbing practitioners.

  19. An absolute measure for a key currency

    NASA Astrophysics Data System (ADS)

    Oya, Shunsuke; Aihara, Kazuyuki; Hirata, Yoshito

    It is generally considered that the US dollar and the euro are the key currencies in the world and in Europe, respectively. However, there is no absolute general measure for a key currency. Here, we investigate the 24-hour periodicity of foreign exchange markets using a recurrence plot, and define an absolute measure for a key currency based on the strength of the periodicity. Moreover, we analyze the time evolution of this measure. The results show that the credibility of the US dollar has not decreased significantly since the Lehman shock, when the Lehman Brothers bankrupted and influenced the economic markets, and has increased even relatively better than that of the euro and that of the Japanese yen.

  20. Probing absolute spin polarization at the nanoscale.

    PubMed

    Eltschka, Matthias; Jäck, Berthold; Assig, Maximilian; Kondrashov, Oleg V; Skvortsov, Mikhail A; Etzkorn, Markus; Ast, Christian R; Kern, Klaus

    2014-12-10

    Probing absolute values of spin polarization at the nanoscale offers insight into the fundamental mechanisms of spin-dependent transport. Employing the Zeeman splitting in superconducting tips (Meservey-Tedrow-Fulde effect), we introduce a novel spin-polarized scanning tunneling microscopy that combines the probing capability of the absolute values of spin polarization with precise control at the atomic scale. We utilize our novel approach to measure the locally resolved spin polarization of magnetic Co nanoislands on Cu(111). We find that the spin polarization is enhanced by 65% when increasing the width of the tunnel barrier by only 2.3 Å due to the different decay of the electron orbitals into vacuum. PMID:25423049

  1. Absolute radiometry and the solar constant

    NASA Technical Reports Server (NTRS)

    Willson, R. C.

    1974-01-01

    A series of active cavity radiometers (ACRs) are described which have been developed as standard detectors for the accurate measurement of irradiance in absolute units. It is noted that the ACR is an electrical substitution calorimeter, is designed for automatic remote operation in any environment, and can make irradiance measurements in the range from low-level IR fluxes up to 30 solar constants with small absolute uncertainty. The instrument operates in a differential mode by chopping the radiant flux to be measured at a slow rate, and irradiance is determined from two electrical power measurements together with the instrumental constant. Results are reported for measurements of the solar constant with two types of ACRs. The more accurate measurement yielded a value of 136.6 plus or minus 0.7 mW/sq cm (1.958 plus or minus 0.010 cal/sq cm per min).

  2. From Hubble's NGSL to Absolute Fluxes

    NASA Technical Reports Server (NTRS)

    Heap, Sara R.; Lindler, Don

    2012-01-01

    Hubble's Next Generation Spectral Library (NGSL) consists of R-l000 spectra of 374 stars of assorted temperature, gravity, and metallicity. Each spectrum covers the wavelength range, 0.18-1.00 microns. The library can be viewed and/or downloaded from the website, http://archive.stsci.edu/prepds/stisngsll. Stars in the NGSL are now being used as absolute flux standards at ground-based observatories. However, the uncertainty in the absolute flux is about 2%, which does not meet the requirements of dark-energy surveys. We are therefore developing an observing procedure that should yield fluxes with uncertainties less than 1 % and will take part in an HST proposal to observe up to 15 stars using this new procedure.

  3. Impact of Winko on absolute discharges.

    PubMed

    Balachandra, Krishna; Swaminath, Sam; Litman, Larry C

    2004-01-01

    In Canada, case laws have had a significant impact on the way mentally ill offenders are managed, both in the criminal justice system and in the forensic mental health system. The Supreme Court of Canada's decision with respect to Winko has set a major precedent in the application of the test of significant risk to the safety of the public in making dispositions by the Ontario Review Board and granting absolute discharges to the mentally ill offenders in the forensic health system. Our study examines the impact of the Supreme Court of Canada's decision before and after Winko. The results show that the numbers of absolute discharges have increased post-Winko, which was statistically significant, but there could be other factors influencing this increase.

  4. Asteroid absolute magnitudes and slope parameters

    NASA Technical Reports Server (NTRS)

    Tedesco, Edward F.

    1991-01-01

    A new listing of absolute magnitudes (H) and slope parameters (G) has been created and published in the Minor Planet Circulars; this same listing will appear in the 1992 Ephemerides of Minor Planets. Unlike previous listings, the values of the current list were derived from fits of data at the V band. All observations were reduced in the same fashion using, where appropriate, a single basis default value of 0.15 for the slope parameter. Distances and phase angles were computed for each observation. The data for 113 asteroids was of sufficiently high quality to permit derivation of their H and G. These improved absolute magnitudes and slope parameters will be used to deduce the most reliable bias-corrected asteroid size-frequency distribution yet made.

  5. Absolute and relative dosimetry for ELIMED

    SciTech Connect

    Cirrone, G. A. P.; Schillaci, F.; Scuderi, V.; Cuttone, G.; Candiano, G.; Musumarra, A.; Pisciotta, P.; Romano, F.; Carpinelli, M.; Presti, D. Lo; Raffaele, L.; Tramontana, A.; Cirio, R.; Sacchi, R.; Monaco, V.; Marchetto, F.; Giordanengo, S.

    2013-07-26

    The definition of detectors, methods and procedures for the absolute and relative dosimetry of laser-driven proton beams is a crucial step toward the clinical use of this new kind of beams. Hence, one of the ELIMED task, will be the definition of procedures aiming to obtain an absolute dose measure at the end of the transport beamline with an accuracy as close as possible to the one required for clinical applications (i.e. of the order of 5% or less). Relative dosimetry procedures must be established, as well: they are necessary in order to determine and verify the beam dose distributions and to monitor the beam fluence and the energetic spectra during irradiations. Radiochromic films, CR39, Faraday Cup, Secondary Emission Monitor (SEM) and transmission ionization chamber will be considered, designed and studied in order to perform a fully dosimetric characterization of the ELIMED proton beam.

  6. Absolute far-ultraviolet spectrophotometry of hot subluminous stars from Voyager

    SciTech Connect

    Holberg, J.B.; Ali, B.; Carone, T.E.; Polidan, R.S. NASA, Goddard Space Flight Center, Greenbelt, MD )

    1991-07-01

    Observations, obtained with the Voyager ultraviolet spectrometers, are presented of absolute fluxes for two well-known hot subluminous stars: BD + 28 deg 4211, an sdO, and G191 - B2B, a hot DA white dwarf. Complete absolute energy distributions for these two stars, from the Lyman limit at 912 A to 1 micron, are given. For BD + 28 deg 4211, a single power law closely represents the entire observed energy distribution. For G191 - B2B, a pure hydrogen model atmosphere provides an excellent match to the entire absolute energy distribution. Voyager absolute fluxes are discussed in relation to those reported from various sounding rocket experiments, including a recent rocket observation of BD + 28 deg 4211. 43 refs.

  7. Absolute far-ultraviolet spectrophotometry of hot subluminous stars from Voyager

    NASA Technical Reports Server (NTRS)

    Holberg, J. B.; Ali, B.; Carone, T. E.; Polidan, R. S.

    1991-01-01

    Observations, obtained with the Voyager ultraviolet spectrometers, are presented of absolute fluxes for two well-known hot subluminous stars: BD + 28 deg 4211, an sdO, and G191 - B2B, a hot DA white dwarf. Complete absolute energy distributions for these two stars, from the Lyman limit at 912 A to 1 micron, are given. For BD + 28 deg 4211, a single power law closely represents the entire observed energy distribution. For G191 - B2B, a pure hydrogen model atmosphere provides an excellent match to the entire absolute energy distribution. Voyager absolute fluxes are discussed in relation to those reported from various sounding rocket experiments, including a recent rocket observation of BD + 28 deg 4211.

  8. Absolute photoionization cross sections of atomic oxygen

    NASA Technical Reports Server (NTRS)

    Samson, J. A. R.; Pareek, P. N.

    1985-01-01

    The absolute values of photoionization cross sections of atomic oxygen were measured from the ionization threshold to 120 A. An auto-ionizing resonance belonging to the 2S2P4(4P)3P(3Do, 3So) transition was observed at 479.43 A and another line at 389.97 A. The experimental data is in excellent agreement with rigorous close-coupling calculations that include electron correlations in both the initial and final states.

  9. Absolute photoionization cross sections of atomic oxygen

    NASA Technical Reports Server (NTRS)

    Samson, J. A. R.; Pareek, P. N.

    1982-01-01

    The absolute values of photoionization cross sections of atomic oxygen were measured from the ionization threshold to 120 A. An auto-ionizing resonance belonging to the 2S2P4(4P)3P(3Do, 3So) transition was observed at 479.43 A and another line at 389.97 A. The experimental data is in excellent agreement with rigorous close-coupling calculations that include electron correlations in both the initial and final states.

  10. Relative errors can cue absolute visuomotor mappings.

    PubMed

    van Dam, Loes C J; Ernst, Marc O

    2015-12-01

    When repeatedly switching between two visuomotor mappings, e.g. in a reaching or pointing task, adaptation tends to speed up over time. That is, when the error in the feedback corresponds to a mapping switch, fast adaptation occurs. Yet, what is learned, the relative error or the absolute mappings? When switching between mappings, errors with a size corresponding to the relative difference between the mappings will occur more often than other large errors. Thus, we could learn to correct more for errors with this familiar size (Error Learning). On the other hand, it has been shown that the human visuomotor system can store several absolute visuomotor mappings (Mapping Learning) and can use associated contextual cues to retrieve them. Thus, when contextual information is present, no error feedback is needed to switch between mappings. Using a rapid pointing task, we investigated how these two types of learning may each contribute when repeatedly switching between mappings in the absence of task-irrelevant contextual cues. After training, we examined how participants changed their behaviour when a single error probe indicated either the often-experienced error (Error Learning) or one of the previously experienced absolute mappings (Mapping Learning). Results were consistent with Mapping Learning despite the relative nature of the error information in the feedback. This shows that errors in the feedback can have a double role in visuomotor behaviour: they drive the general adaptation process by making corrections possible on subsequent movements, as well as serve as contextual cues that can signal a learned absolute mapping. PMID:26280315

  11. The absolute spectrophotometric catalog by Anita Cochran

    NASA Astrophysics Data System (ADS)

    Burnashev, V. I.; Burnasheva, B. A.; Ruban, E. V.; Hagen-Torn, E. I.

    2014-06-01

    The absolute spectrophotometric catalog by Anita Cochran is presented in a machine-readable form. The catalog systematizes observations acquired at the McDonald Observatory in 1977-1978. The data are compared with other sources, in particular, the calculated broadband stellar magnitudes are compared with photometric observations by other authors, to show that the observational data given in the catalog are reliable and suitable for a variety of applications. Observations of variable stars of different types make Cochran's catalog especially valuable.

  12. Absolute magnitudes and kinematics of barium stars.

    NASA Astrophysics Data System (ADS)

    Gomez, A. E.; Luri, X.; Grenier, S.; Prevot, L.; Mennessier, M. O.; Figueras, F.; Torra, J.

    1997-03-01

    The absolute magnitude of barium stars has been obtained from kinematical data using a new algorithm based on the maximum-likelihood principle. The method allows to separate a sample into groups characterized by different mean absolute magnitudes, kinematics and z-scale heights. It also takes into account, simultaneously, the censorship in the sample and the errors on the observables. The method has been applied to a sample of 318 barium stars. Four groups have been detected. Three of them show a kinematical behaviour corresponding to disk population stars. The fourth group contains stars with halo kinematics. The luminosities of the disk population groups spread a large range. The intrinsically brightest one (M_v_=-1.5mag, σ_M_=0.5mag) seems to be an inhomogeneous group containing barium binaries as well as AGB single stars. The most numerous group (about 150 stars) has a mean absolute magnitude corresponding to stars in the red giant branch (M_v_=0.9mag, σ_M_=0.8mag). The third group contains barium dwarfs, the obtained mean absolute magnitude is characteristic of stars on the main sequence or on the subgiant branch (M_v_=3.3mag, σ_M_=0.5mag). The obtained mean luminosities as well as the kinematical results are compatible with an evolutionary link between barium dwarfs and classical barium giants. The highly luminous group is not linked with these last two groups. More high-resolution spectroscopic data will be necessary in order to better discriminate between barium and non-barium stars.

  13. Chemical composition of French mimosa absolute oil.

    PubMed

    Perriot, Rodolphe; Breme, Katharina; Meierhenrich, Uwe J; Carenini, Elise; Ferrando, Georges; Baldovini, Nicolas

    2010-02-10

    Since decades mimosa (Acacia dealbata) absolute oil has been used in the flavor and perfume industry. Today, it finds an application in over 80 perfumes, and its worldwide industrial production is estimated five tons per year. Here we report on the chemical composition of French mimosa absolute oil. Straight-chain analogues from C6 to C26 with different functional groups (hydrocarbons, esters, aldehydes, diethyl acetals, alcohols, and ketones) were identified in the volatile fraction. Most of them are long-chain molecules: (Z)-heptadec-8-ene, heptadecane, nonadecane, and palmitic acid are the most abundant, and constituents such as 2-phenethyl alcohol, methyl anisate, and ethyl palmitate are present in smaller amounts. The heavier constituents were mainly triterpenoids such as lupenone and lupeol, which were identified as two of the main components. (Z)-Heptadec-8-ene, lupenone, and lupeol were quantified by GC-MS in SIM mode using external standards and represents 6%, 20%, and 7.8% (w/w) of the absolute oil. Moreover, odorant compounds were extracted by SPME and analyzed by GC-sniffing leading to the perception of 57 odorant zones, of which 37 compounds were identified by their odorant description, mass spectrum, retention index, and injection of the reference compound. PMID:20070087

  14. Measurement of absolute gravity acceleration in Firenze

    NASA Astrophysics Data System (ADS)

    de Angelis, M.; Greco, F.; Pistorio, A.; Poli, N.; Prevedelli, M.; Saccorotti, G.; Sorrentino, F.; Tino, G. M.

    2011-01-01

    This paper reports the results from the accurate measurement of the acceleration of gravity g taken at two separate premises in the Polo Scientifico of the University of Firenze (Italy). In these laboratories, two separate experiments aiming at measuring the Newtonian constant and testing the Newtonian law at short distances are in progress. Both experiments require an independent knowledge on the local value of g. The only available datum, pertaining to the italian zero-order gravity network, was taken more than 20 years ago at a distance of more than 60 km from the study site. Gravity measurements were conducted using an FG5 absolute gravimeter, and accompanied by seismic recordings for evaluating the noise condition at the site. The absolute accelerations of gravity at the two laboratories are (980 492 160.6 ± 4.0) μGal and (980 492 048.3 ± 3.0) μGal for the European Laboratory for Non-Linear Spectroscopy (LENS) and Dipartimento di Fisica e Astronomia, respectively. Other than for the two referenced experiments, the data here presented will serve as a benchmark for any future study requiring an accurate knowledge of the absolute value of the acceleration of gravity in the study region.

  15. A Methodology for Absolute Isotope Composition Measurement

    NASA Astrophysics Data System (ADS)

    Shen, J. J.; Lee, D.; Liang, W.

    2007-12-01

    Double spike technique was a well defined method for isotope composition measurement by TIMS of samples which have natural mass fractionation effect, but it is still a problem to define the isotope composition for double spike itself. In this study, we modified the old double spike technique and found that we could use the modified technique to solve the ¡§true¡¨ isotope composition of double spike itself. According the true isotope composition of double spike, we can measure the absolute isotope composition if the sample has natural fractionation effect. A new vector analytical method has been developed in order to obtain the true isotopic composition of a 42Ca-48Ca double spike, and this is achieved by using two different sample-spike mixtures combined with the double spike and the natural Ca data. Because the natural sample, the two mixtures, and the spike should all lie on a single mixing line, we are able to constrain the true isotopic composition of our double spike using this new approach. This method not only can be used in Ca system but also in Ti, Cr, Fe, Ni, Zn, Mo, Ba and Pb systems. The absolute double spike isotopic ratio is important, which can save a lot of time to check different reference standards. Especially for Pb, radiogenic isotope system, the decay systems embodied in three of four naturally occurring isotopes induce difficult to obtain true isotopic ratios for absolute dating.

  16. Chemical composition of French mimosa absolute oil.

    PubMed

    Perriot, Rodolphe; Breme, Katharina; Meierhenrich, Uwe J; Carenini, Elise; Ferrando, Georges; Baldovini, Nicolas

    2010-02-10

    Since decades mimosa (Acacia dealbata) absolute oil has been used in the flavor and perfume industry. Today, it finds an application in over 80 perfumes, and its worldwide industrial production is estimated five tons per year. Here we report on the chemical composition of French mimosa absolute oil. Straight-chain analogues from C6 to C26 with different functional groups (hydrocarbons, esters, aldehydes, diethyl acetals, alcohols, and ketones) were identified in the volatile fraction. Most of them are long-chain molecules: (Z)-heptadec-8-ene, heptadecane, nonadecane, and palmitic acid are the most abundant, and constituents such as 2-phenethyl alcohol, methyl anisate, and ethyl palmitate are present in smaller amounts. The heavier constituents were mainly triterpenoids such as lupenone and lupeol, which were identified as two of the main components. (Z)-Heptadec-8-ene, lupenone, and lupeol were quantified by GC-MS in SIM mode using external standards and represents 6%, 20%, and 7.8% (w/w) of the absolute oil. Moreover, odorant compounds were extracted by SPME and analyzed by GC-sniffing leading to the perception of 57 odorant zones, of which 37 compounds were identified by their odorant description, mass spectrum, retention index, and injection of the reference compound.

  17. The Carina Project: Absolute and Relative Calibrations

    NASA Astrophysics Data System (ADS)

    Corsi, C. E.; Bono, G.; Walker, A. R.; Brocato, E.; Buonanno, R.; Caputo, F.; Castellani, M.; Castellani, V.; Dall'Ora, M.; Marconi, M.; Monelli, M.; Nonino, M.; Pulone, L.; Ripepi, V.; Smith, H. A.

    We discuss the reduction strategy adopted to perform the relative and the absolute calibration of the Wide Field Imager (WFI) available at the 2.2m ESO/MPI telescope and of the Mosaic Camera (MC) available at the 4m CTIO Blanco telescope. To properly constrain the occurrence of deceptive systematic errors in the relative calibration we observed with each chip the same set of stars. Current photometry seems to suggest that the WFI shows a positional effect when moving from the top to the bottom of individual chips. Preliminary results based on an independent data set collected with the MC suggest that this camera is only marginally affected by the same problem. To perform the absolute calibration we observed with each chip the same set of standard stars. The sample covers a wide color range and the accuracy both in the B and in the V-band appears to be of the order of a few hundredths of magnitude. Finally, we briefly outline the observing strategy to improve both relative and absolute calibrations of mosaic CCD cameras.

  18. Conductance and Absolutely Continuous Spectrum of 1D Samples

    NASA Astrophysics Data System (ADS)

    Bruneau, L.; Jakšić, V.; Last, Y.; Pillet, C.-A.

    2016-06-01

    We characterize the absolutely continuous spectrum of the one-dimensional Schrödinger operators {h = -Δ + v} acting on {ℓ^2(mathbb{Z}_+)} in terms of the limiting behaviour of the Landauer-Büttiker and Thouless conductances of the associated finite samples. The finite sample is defined by restricting h to a finite interval {[1, L] \\cap mathbb{Z}_+} and the conductance refers to the charge current across the sample in the open quantum system obtained by attaching independent electronic reservoirs to the sample ends. Our main result is that the conductances associated to an energy interval {I} are non-vanishing in the limit {L to infty} iff {sp_ac(h) \\cap I neq emptyset}. We also discuss the relationship between this result and the Schrödinger Conjecture (Avila, J Am Math Soc 28:579-616, 2015; Bruneau et al., Commun Math Phys 319:501-513, 2013).

  19. Absolute quantification of cell-bound DNA aptamers during SELEX.

    PubMed

    Avci-Adali, Meltem; Wilhelm, Nadja; Perle, Nadja; Stoll, Heidi; Schlensak, Christian; Wendel, Hans P

    2013-04-01

    In the fields of diagnosis, imaging, regenerative medicine, and drug targeting, aptamers are promising nucleic acid ligands for specific recognition and binding of whole living cells. These aptamers are selected by a combinatorial chemistry technique called cell-SELEX (Systematic Evolution of Ligands by EXponential enrichment). During this iterative procedure of in vitro selection and enzymatic amplification, the enrichment of cell binding aptamers is generally monitored by flow cytometry. This method needs the use of fluorophore-labeled oligonucleotides for detection and allows only the relative evaluation of the aptamer binding compared with the control. Here, we describe the development and validation of a new quantitative real time polymerase chain reaction (qPCR) method for the absolute determination of cell bound aptamers during cell-SELEX. The method is based on SYBR Green I real-time PCR technology and uses an aptamer standard curve to determine the accurate aptamer amount on cells after the incubations. Lysates of cells with bound aptamers were used to identify the absolute amount of aptamers on cells. This method is highly sensitive and allows the detection of very small quantities of aptamers in cell lysate samples. The lower detection limit is 20 fg. The established qPCR method can be used as an additional monitoring tool during cell-SELEX to determine the enrichment of cell binding aptamers on cells, whereby the absolute quantity is determined. Furthermore, the contamination of the amplified aptamer pool with by-products can be prevented by prior determination of bound aptamer amount on cells. PMID:23405949

  20. Clock time is absolute and universal

    NASA Astrophysics Data System (ADS)

    Shen, Xinhang

    2015-09-01

    A critical error is found in the Special Theory of Relativity (STR): mixing up the concepts of the STR abstract time of a reference frame and the displayed time of a physical clock, which leads to use the properties of the abstract time to predict time dilation on physical clocks and all other physical processes. Actually, a clock can never directly measure the abstract time, but can only record the result of a physical process during a period of the abstract time such as the number of cycles of oscillation which is the multiplication of the abstract time and the frequency of oscillation. After Lorentz Transformation, the abstract time of a reference frame expands by a factor gamma, but the frequency of a clock decreases by the same factor gamma, and the resulting multiplication i.e. the displayed time of a moving clock remains unchanged. That is, the displayed time of any physical clock is an invariant of Lorentz Transformation. The Lorentz invariance of the displayed times of clocks can further prove within the framework of STR our earth based standard physical time is absolute, universal and independent of inertial reference frames as confirmed by both the physical fact of the universal synchronization of clocks on the GPS satellites and clocks on the earth, and the theoretical existence of the absolute and universal Galilean time in STR which has proved that time dilation and space contraction are pure illusions of STR. The existence of the absolute and universal time in STR has directly denied that the reference frame dependent abstract time of STR is the physical time, and therefore, STR is wrong and all its predictions can never happen in the physical world.

  1. Achieving Climate Change Absolute Accuracy in Orbit

    NASA Technical Reports Server (NTRS)

    Wielicki, Bruce A.; Young, D. F.; Mlynczak, M. G.; Thome, K. J; Leroy, S.; Corliss, J.; Anderson, J. G.; Ao, C. O.; Bantges, R.; Best, F.; Bowman, K.; Brindley, H.; Butler, J. J.; Collins, W.; Dykema, J. A.; Doelling, D. R.; Feldman, D. R.; Fox, N.; Huang, X.; Holz, R.; Huang, Y.; Jennings, D.; Jin, Z.; Johnson, D. G.; Jucks, K.; Kato, S.; Kratz, D. P.; Liu, X.; Lukashin, C.; Mannucci, A. J.; Phojanamongkolkij, N.; Roithmayr, C. M.; Sandford, S.; Taylor, P. C.; Xiong, X.

    2013-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission will provide a calibration laboratory in orbit for the purpose of accurately measuring and attributing climate change. CLARREO measurements establish new climate change benchmarks with high absolute radiometric accuracy and high statistical confidence across a wide range of essential climate variables. CLARREO's inherently high absolute accuracy will be verified and traceable on orbit to Système Internationale (SI) units. The benchmarks established by CLARREO will be critical for assessing changes in the Earth system and climate model predictive capabilities for decades into the future as society works to meet the challenge of optimizing strategies for mitigating and adapting to climate change. The CLARREO benchmarks are derived from measurements of the Earth's thermal infrared spectrum (5-50 micron), the spectrum of solar radiation reflected by the Earth and its atmosphere (320-2300 nm), and radio occultation refractivity from which accurate temperature profiles are derived. The mission has the ability to provide new spectral fingerprints of climate change, as well as to provide the first orbiting radiometer with accuracy sufficient to serve as the reference transfer standard for other space sensors, in essence serving as a "NIST [National Institute of Standards and Technology] in orbit." CLARREO will greatly improve the accuracy and relevance of a wide range of space-borne instruments for decadal climate change. Finally, CLARREO has developed new metrics and methods for determining the accuracy requirements of climate observations for a wide range of climate variables and uncertainty sources. These methods should be useful for improving our understanding of observing requirements for most climate change observations.

  2. Absolute calibration of the Auger fluorescence detectors

    SciTech Connect

    Bauleo, P.; Brack, J.; Garrard, L.; Harton, J.; Knapik, R.; Meyhandan, R.; Rovero, A.C.; Tamashiro, A.; Warner, D.

    2005-07-01

    Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a light source at the telescope aperture. The technique accounts for the combined effects of all detector components in a single measurement. The calibrated 2.5 m diameter light source fills the aperture, providing uniform illumination to each pixel. The known flux from the light source and the response of the acquisition system give the required calibration for each pixel. In the lab, light source uniformity is studied using CCD images and the intensity is measured relative to NIST-calibrated photodiodes. Overall uncertainties are presently 12%, and are dominated by systematics.

  3. Absolute rate theories of epigenetic stability

    NASA Astrophysics Data System (ADS)

    Walczak, Aleksandra M.; Onuchic, José N.; Wolynes, Peter G.

    2005-12-01

    Spontaneous switching events in most characterized genetic switches are rare, resulting in extremely stable epigenetic properties. We show how simple arguments lead to theories of the rate of such events much like the absolute rate theory of chemical reactions corrected by a transmission factor. Both the probability of the rare cellular states that allow epigenetic escape and the transmission factor depend on the rates of DNA binding and unbinding events and on the rates of protein synthesis and degradation. Different mechanisms of escape from the stable attractors occur in the nonadiabatic, weakly adiabatic, and strictly adiabatic regimes, characterized by the relative values of those input rates. rate theory | stochastic gene expression | gene switches

  4. Characterization of the DARA solar absolute radiometer

    NASA Astrophysics Data System (ADS)

    Finsterle, W.; Suter, M.; Fehlmann, A.; Kopp, G.

    2011-12-01

    The Davos Absolute Radiometer (DARA) prototype is an Electrical Substitution Radiometer (ESR) which has been developed as a successor of the PMO6 type on future space missions and ground based TSI measurements. The DARA implements an improved thermal design of the cavity detector and heat sink assembly to minimize air-vacuum differences and to maximize thermal symmetry of measuring and compensating cavity. The DARA also employs an inverted viewing geometry to reduce internal stray light. We will report on the characterization and calibration experiments which were carried out at PMOD/WRC and LASP (TRF).

  5. Absolute Priority for a Vehicle in VANET

    NASA Astrophysics Data System (ADS)

    Shirani, Rostam; Hendessi, Faramarz; Montazeri, Mohammad Ali; Sheikh Zefreh, Mohammad

    In today's world, traffic jams waste hundreds of hours of our life. This causes many researchers try to resolve the problem with the idea of Intelligent Transportation System. For some applications like a travelling ambulance, it is important to reduce delay even for a second. In this paper, we propose a completely infrastructure-less approach for finding shortest path and controlling traffic light to provide absolute priority for an emergency vehicle. We use the idea of vehicular ad-hoc networking to reduce the imposed travelling time. Then, we simulate our proposed protocol and compare it with a centrally controlled traffic light system.

  6. Absolute method of measuring magnetic susceptibility

    USGS Publications Warehouse

    Thorpe, A.; Senftle, F.E.

    1959-01-01

    An absolute method of standardization and measurement of the magnetic susceptibility of small samples is presented which can be applied to most techniques based on the Faraday method. The fact that the susceptibility is a function of the area under the curve of sample displacement versus distance of the magnet from the sample, offers a simple method of measuring the susceptibility without recourse to a standard sample. Typical results on a few substances are compared with reported values, and an error of less than 2% can be achieved. ?? 1959 The American Institute of Physics.

  7. Absolute velocity measurements in the solar transition region and corona from observations of ultraviolet emission line profiles

    NASA Astrophysics Data System (ADS)

    Hassler, Donald M.

    An experimental technique to measure absolute velocities of minor ions formed in the solar transition region and corona is presented. A sounding rocket experiment July 27, 1987 obtained high resolution extreme ultraviolet (EUV) spectra along a solar diameter with spatial resolution of 20 x 20 arcseconds. The center-to-limb behavior of four representative lines (Si II 1553, Fe II 1563, CIV 1548, Ne VIII 770) formed at different heights in the solar atmosphere is discussed. Assuming that horizontal motions cancel statistically so that the line-of-sight velocity approaches zero at the limb, we find a net radial downflow of approximately 7.5 +/- 1.0 km/s for C IV, 2.7 +/- 1.5 km/s for Fe II 1563, and upper limits of 0 +/- 1.2 km/s and 0 +/- 4 km/s for Si II and Ne VIII, respectively. The absolute wavelengths of each emission line were determined by direct comparison with wavelengths of known platinum lines generated by an inflight calibration lamp. We then test the assumption of line-of-sight velocity approaching zero at the limb by comparing our wavelengths with recently published laboratory rest wavelengths of the solar emission lines. We find agreement within the published uncertainties of the laboratory wavelengths. The result for Si II indicates that the next radial flow in the chromosphere is near zero, although small scale velocity structures may vary by as much as 4-6 km/sec. The center-to-limb behavior of Fe II 1563 suggests, contrary to previous thinking, that there might be a significant contribution of Fe II emission at higher temperatures characteristic of the lower transition region. Finally, the upper limit on the radial flow velocity for Ne VIII provides a constraint on the radial flow at coronal temperatures. Complicating the accurate measurement of Doppler velocities is the presence of small nonlinearities in the microchannel plates used in UV and EUV detectors which introduce small position offsets between the input and output of the detector. The

  8. Absolute Temperature Monitoring Using RF Radiometry in the MRI Scanner.

    PubMed

    El-Sharkawy, Abdel-Monem M; Sotiriadis, Paul P; Bottomley, Paul A; Atalar, Ergin

    2006-11-01

    Temperature detection using microwave radiometry has proven value for noninvasively measuring the absolute temperature of tissues inside the body. However, current clinical radiometers operate in the gigahertz range, which limits their depth of penetration. We have designed and built a noninvasive radiometer which operates at radio frequencies (64 MHz) with ∼100-kHz bandwidth, using an external RF loop coil as a thermal detector. The core of the radiometer is an accurate impedance measurement and automatic matching circuit of 0.05 Ω accuracy to compensate for any load variations. The radiometer permits temperature measurements with accuracy of ±0.1°K, over a tested physiological range of 28° C-40° C in saline phantoms whose electric properties match those of tissue. Because 1.5 T magnetic resonance imaging (MRI) scanners also operate at 64 MHz, we demonstrate the feasibility of integrating our radiometer with an MRI scanner to monitor RF power deposition and temperature dosimetry, obtaining coarse, spatially resolved, absolute thermal maps in the physiological range. We conclude that RF radiometry offers promise as a direct, noninvasive method of monitoring tissue heating during MRI studies and thereby providing an independent means of verifying patient-safe operation. Other potential applications include titration of hyper- and hypo-therapies. PMID:18026562

  9. Absolute analytical prediction of photonic crystal guided mode resonance wavelengths

    SciTech Connect

    Hermannsson, Pétur Gordon; Vannahme, Christoph; Smith, Cameron L. C.; Kristensen, Anders

    2014-08-18

    A class of photonic crystal resonant reflectors known as guided mode resonant filters are optical structures that are widely used in the field of refractive index sensing, particularly in biosensing. For the purposes of understanding and design, their behavior has traditionally been modeled numerically with methods such as rigorous coupled wave analysis. Here it is demonstrated how the absolute resonance wavelengths of such structures can be predicted by analytically modeling them as slab waveguides in which the propagation constant is determined by a phase matching condition. The model is experimentally verified to be capable of predicting the absolute resonance wavelengths to an accuracy of within 0.75 nm, as well as resonance wavelength shifts due to changes in cladding index within an accuracy of 0.45 nm across the visible wavelength regime in the case where material dispersion is taken into account. Furthermore, it is demonstrated that the model is valid beyond the limit of low grating modulation, for periodically discontinuous waveguide layers, high refractive index contrasts, and highly dispersive media.

  10. Sentinel-2/MSI absolute calibration: first results

    NASA Astrophysics Data System (ADS)

    Lonjou, V.; Lachérade, S.; Fougnie, B.; Gamet, P.; Marcq, S.; Raynaud, J.-L.; Tremas, T.

    2015-10-01

    Sentinel-2 is an optical imaging mission devoted to the operational monitoring of land and coastal areas. It is developed in partnership between the European Commission and the European Space Agency. The Sentinel-2 mission is based on a satellites constellation deployed in polar sun-synchronous orbit. It will offer a unique combination of global coverage with a wide field of view (290km), a high revisit (5 days with two satellites), a high resolution (10m, 20m and 60m) and multi-spectral imagery (13 spectral bands in visible and shortwave infra-red domains). CNES is involved in the instrument commissioning in collaboration with ESA. This paper reviews all the techniques that will be used to insure an absolute calibration of the 13 spectral bands better than 5% (target 3%), and will present the first results if available. First, the nominal calibration technique, based on an on-board sun diffuser, is detailed. Then, we show how vicarious calibration methods based on acquisitions over natural targets (oceans, deserts, and Antarctica during winter) will be used to check and improve the accuracy of the absolute calibration coefficients. Finally, the verification scheme, exploiting photometer in-situ measurements over Lacrau plain, is described. A synthesis, including spectral coherence, inter-methods agreement and temporal evolution, will conclude the paper.

  11. Why to compare absolute numbers of mitochondria.

    PubMed

    Schmitt, Sabine; Schulz, Sabine; Schropp, Eva-Maria; Eberhagen, Carola; Simmons, Alisha; Beisker, Wolfgang; Aichler, Michaela; Zischka, Hans

    2014-11-01

    Prompted by pronounced structural differences between rat liver and rat hepatocellular carcinoma mitochondria, we suspected these mitochondrial populations to differ massively in their molecular composition. Aiming to reveal these mitochondrial differences, we came across the issue on how to normalize such comparisons and decided to focus on the absolute number of mitochondria. To this end, fluorescently stained mitochondria were quantified by flow cytometry. For rat liver mitochondria, this approach resulted in mitochondrial protein contents comparable to earlier reports using alternative methods. We determined similar protein contents for rat liver, heart and kidney mitochondria. In contrast, however, lower protein contents were determined for rat brain mitochondria and for mitochondria from the rat hepatocellular carcinoma cell line McA 7777. This result challenges mitochondrial comparisons that rely on equal protein amounts as a typical normalization method. Exemplarily, we therefore compared the activity and susceptibility toward inhibition of complex II of rat liver and hepatocellular carcinoma mitochondria and obtained significant discrepancies by either normalizing to protein amount or to absolute mitochondrial number. Importantly, the latter normalization, in contrast to the former, demonstrated a lower complex II activity and higher susceptibility toward inhibition in hepatocellular carcinoma mitochondria compared to liver mitochondria. These findings demonstrate that solely normalizing to protein amount may obscure essential molecular differences between mitochondrial populations.

  12. Absolute Proper Motions of Southern Globular Clusters

    NASA Astrophysics Data System (ADS)

    Dinescu, D. I.; Girard, T. M.; van Altena, W. F.

    1996-05-01

    Our program involves the determination of absolute proper motions with respect to galaxies for a sample of globular clusters situated in the southern sky. The plates cover a 6(deg) x 6(deg) area and are taken with the 51-cm double astrograph at Cesco Observatory in El Leoncito, Argentina. We have developed special methods to deal with the modelling error of the plate transformation and we correct for magnitude equation using the cluster stars. This careful astrometric treatment leads to accuracies of from 0.5 to 1.0 mas/yr for the absolute proper motion of each cluster, depending primarily on the number of measurable cluster stars which in turn is related to the cluster's distance. Space velocities are then derived which, in association with metallicities, provide key information for the formation scenario of the Galaxy, i.e. accretion and/or dissipational collapse. Here we present results for NGC 1851, NGC 6752, NGC 6584, NGC 6362 and NGC 288.

  13. Relational versus absolute representation in categorization.

    PubMed

    Edwards, Darren J; Pothos, Emmanuel M; Perlman, Amotz

    2012-01-01

    This study explores relational-like and absolute-like representations in categorization. Although there is much evidence that categorization processes can involve information about both the particular physical properties of studied instances and abstract (relational) properties, there has been little work on the factors that lead to one kind of representation as opposed to the other. We tested 370 participants in 6 experiments, in which participants had to classify new items into predefined artificial categories. In 4 experiments, we observed a predominantly relational-like mode of classification, and in 2 experiments we observed a shift toward an absolute-like mode of classification. These results suggest 3 factors that promote a relational-like mode of classification: fewer items per group, more training groups, and the presence of a time delay. Overall, we propose that less information about the distributional properties of a category or weaker memory traces for the category exemplars (induced, e.g., by having smaller categories or a time delay) can encourage relational-like categorization.

  14. Transient absolute robustness in stochastic biochemical networks.

    PubMed

    Enciso, German A

    2016-08-01

    Absolute robustness allows biochemical networks to sustain a consistent steady-state output in the face of protein concentration variability from cell to cell. This property is structural and can be determined from the topology of the network alone regardless of rate parameters. An important question regarding these systems is the effect of discrete biochemical noise in the dynamical behaviour. In this paper, a variable freezing technique is developed to show that under mild hypotheses the corresponding stochastic system has a transiently robust behaviour. Specifically, after finite time the distribution of the output approximates a Poisson distribution, centred around the deterministic mean. The approximation becomes increasingly accurate, and it holds for increasingly long finite times, as the total protein concentrations grow to infinity. In particular, the stochastic system retains a transient, absolutely robust behaviour corresponding to the deterministic case. This result contrasts with the long-term dynamics of the stochastic system, which eventually must undergo an extinction event that eliminates robustness and is completely different from the deterministic dynamics. The transiently robust behaviour may be sufficient to carry out many forms of robust signal transduction and cellular decision-making in cellular organisms. PMID:27581485

  15. A Conceptual Approach to Absolute Value Equations and Inequalities

    ERIC Educational Resources Information Center

    Ellis, Mark W.; Bryson, Janet L.

    2011-01-01

    The absolute value learning objective in high school mathematics requires students to solve far more complex absolute value equations and inequalities. When absolute value problems become more complex, students often do not have sufficient conceptual understanding to make any sense of what is happening mathematically. The authors suggest that the…

  16. Using, Seeing, Feeling, and Doing Absolute Value for Deeper Understanding

    ERIC Educational Resources Information Center

    Ponce, Gregorio A.

    2008-01-01

    Using sticky notes and number lines, a hands-on activity is shared that anchors initial student thinking about absolute value. The initial point of reference should help students successfully evaluate numeric problems involving absolute value. They should also be able to solve absolute value equations and inequalities that are typically found in…

  17. Relationship between the upper mantle high velocity seismic lid and the continental lithosphere

    NASA Astrophysics Data System (ADS)

    Priestley, Keith; Tilmann, Frederik

    2009-04-01

    The lithosphere-asthenosphere boundary corresponds to the base of the "rigid" plates - the depth at which heat transport changes from advection in the convecting deeper upper mantle to conduction in the shallow upper mantle. Although this boundary is a fundamental feature of the Earth, mapping it has been difficult because it does not correspond to a sharp change in temperature or composition. Various definitions of the lithosphere and asthenosphere are based on the analysis of different types of geophysical and geological observations. The depth to the lithosphere-asthenosphere boundary determined from these different observations often shows little agreement when they are applied to the same region because the geophysical and geological observations (i.e., seismic velocity, strain rate, electrical resistivity, chemical depletion, etc.) are proxies for the change in rheological properties rather than a direct measure of the rheological properties. In this paper, we focus on the seismic mapping of the upper mantle high velocity lid and low velocity zone and its relationship to the lithosphere and asthenosphere. We have two goals: (a) to examine the differences in how teleseismic body-wave travel-time tomography and surface-wave tomography image upper mantle seismic structure; and (b) to summarise how upper mantle seismic velocity structure can be related to the structure of the lithosphere and asthenosphere. Surface-wave tomography provides reasonably good depth resolution, especially when higher modes are included in the analysis, but lateral resolution is limited by the horizontal wavelength of the long-period surface waves used to constrain upper mantle velocity structure. Teleseismic body-wave tomography has poor depth resolution in the upper mantle, particularly when no strong lateral contrasts are present. If station terms are used, features with large lateral extent and gradual boundaries are attenuated in the tomographic image. Body-wave models are not

  18. Absolute positioning using DORIS tracking of the SPOT-2 satellite

    NASA Technical Reports Server (NTRS)

    Watkins, M. M.; Ries, J. C.; Davis, G. W.

    1992-01-01

    The ability of the French DORIS system operating on the SPOT-2 satellite to provide absolute site positioning at the 20-30-centimeter level using 80 d of data is demonstrated. The accuracy of the vertical component is comparable to that of the horizontal components, indicating that residual troposphere error is not a limiting factor. The translation parameters indicate that the DORIS network realizes a geocentric frame to about 50 nm in each component. The considerable amount of data provided by the nearly global, all-weather DORIS network allowed this complex parameterization required to reduce the unmodeled forces acting on the low-earth satellite. Site velocities with accuracies better than 10 mm/yr should certainly be possible using the multiyear span of the SPOT series and Topex/Poseidon missions.

  19. Absolute stellar photometry on moderate-resolution FPA images

    USGS Publications Warehouse

    Stone, T.C.

    2009-01-01

    An extensive database of star (and Moon) images has been collected by the ground-based RObotic Lunar Observatory (ROLO) as part of the US Geological Survey program for lunar calibration. The stellar data are used to derive nightly atmospheric corrections for the observations from extinction measurements, and absolute calibration of the ROLO sensors is based on observations of Vega and published reference flux and spectrum data. The ROLO telescopes were designed for imaging the Moon at moderate resolution, thus imposing some limitations for the stellar photometry. Attaining accurate stellar photometry with the ROLO image data has required development of specialized processing techniques. A key consideration is consistency in discriminating the star core signal from the off-axis point spread function. The analysis and processing methods applied to the ROLO stellar image database are described. ?? 2009 BIPM and IOP Publishing Ltd.

  20. Absolute Radiation Measurements in Earth and Mars Entry Conditions

    NASA Technical Reports Server (NTRS)

    Cruden, Brett A.

    2014-01-01

    This paper reports on the measurement of radiative heating for shock heated flows which simulate conditions for Mars and Earth entries. Radiation measurements are made in NASA Ames' Electric Arc Shock Tube at velocities from 3-15 km/s in mixtures of N2/O2 and CO2/N2/Ar. The technique and limitations of the measurement are summarized in some detail. The absolute measurements will be discussed in regards to spectral features, radiative magnitude and spatiotemporal trends. Via analysis of spectra it is possible to extract properties such as electron density, and rotational, vibrational and electronic temperatures. Relaxation behind the shock is analyzed to determine how these properties relax to equilibrium and are used to validate and refine kinetic models. It is found that, for some conditions, some of these values diverge from non-equilibrium indicating a lack of similarity between the shock tube and free flight conditions. Possible reasons for this are discussed.

  1. Relative and Absolute Error Control in a Finite-Difference Method Solution of Poisson's Equation

    ERIC Educational Resources Information Center

    Prentice, J. S. C.

    2012-01-01

    An algorithm for error control (absolute and relative) in the five-point finite-difference method applied to Poisson's equation is described. The algorithm is based on discretization of the domain of the problem by means of three rectilinear grids, each of different resolution. We discuss some hardware limitations associated with the algorithm,…

  2. The Absolute Radiometric Calibration of Space - Sensors.

    NASA Astrophysics Data System (ADS)

    Holm, Ronald Gene

    1987-09-01

    The need for absolute radiometric calibration of space-based sensors will continue to increase as new generations of space sensors are developed. A reflectance -based in-flight calibration procedure is used to determine the radiance reaching the entrance pupil of the sensor. This procedure uses ground-based measurements coupled with a radiative transfer code to characterize the effects the atmosphere has on the signal reaching the sensor. The computed radiance is compared to the digital count output of the sensor associated with the image of a test site. This provides an update to the preflight calibration of the system and a check on the on-board internal calibrator. This calibration procedure was used to perform a series of five calibrations of the Landsat-5 Thematic Mapper (TM). For the 12 measurements made in TM bands 1-3, the RMS variation from the mean as a percentage of the mean is (+OR-) 1.9%, and for measurements in the IR, TM bands 4,5, and 7, the value is (+OR-) 3.4%. The RMS variation for all 23 measurements is (+OR-) 2.8%. The absolute calibration techniques were put to another test with a series of three calibration of the SPOT-1 High Resolution Visible, (HRV), sensors. The ratio, HRV-2/HRV-1, of absolute calibration coefficients compared very well with ratios of histogrammed data obtained when the cameras simultaneously imaged the same ground site. Bands PA, B1 and B3 agreed to within 3%, while band B2 showed a 7% difference. The procedure for performing a satellite calibration was then used to demonstrate how a calibrated satellite sensor can be used to quantitatively evaluate surface reflectance over a wide range of surface features. Predicted reflectance factors were compared to values obtained from aircraft -based radiometer data. This procedure was applied on four dates with two different surface conditions per date. A strong correlation, R('2) = .996, was shown between reflectance values determined from satellite imagery and low-flying aircraft

  3. Use of Absolute and Comparative Performance Feedback in Absolute and Comparative Judgments and Decisions

    ERIC Educational Resources Information Center

    Moore, Don A.; Klein, William M. P.

    2008-01-01

    Which matters more--beliefs about absolute ability or ability relative to others? This study set out to compare the effects of such beliefs on satisfaction with performance, self-evaluations, and bets on future performance. In Experiment 1, undergraduate participants were told they had answered 20% correct, 80% correct, or were not given their…

  4. Absolute radiometric calibration of the CCRS SAR

    NASA Astrophysics Data System (ADS)

    Ulander, Lars M. H.; Hawkins, Robert K.; Livingstone, Charles E.; Lukowski, Tom I.

    1991-11-01

    Determining the radar scattering coefficients from SAR (synthetic aperture radar) image data requires absolute radiometric calibration of the SAR system. The authors describe an internal calibration methodology for the airborne Canada Centre for Remote Sensing (CCRS) SAR system, based on radar theory, a detailed model of the radar system, and measurements of system parameters. The methodology is verified by analyzing external calibration data acquired over a 6-month period in 1988 by the C-band radar using HH polarization. The results indicate that the overall error is +/- 0.8 dB (1-sigma) for incidence angles +/- 20 deg from antenna boresight. The dominant error contributions are due to the antenna radome and uncertainties in the elevation angle relative to the antenna boresight.

  5. Absolute calibration of ultraviolet filter photometry

    NASA Technical Reports Server (NTRS)

    Bless, R. C.; Fairchild, T.; Code, A. D.

    1972-01-01

    The essential features of the calibration procedure can be divided into three parts. First, the shape of the bandpass of each photometer was determined by measuring the transmissions of the individual optical components and also by measuring the response of the photometer as a whole. Secondly, each photometer was placed in the essentially-collimated synchrotron radiation bundle maintained at a constant intensity level, and the output signal was determined from about 100 points on the objective. Finally, two or three points on the objective were illuminated by synchrotron radiation at several different intensity levels covering the dynamic range of the photometers. The output signals were placed on an absolute basis by the electron counting technique described earlier.

  6. Absolute measurements of fast neutrons using yttrium

    SciTech Connect

    Roshan, M. V.; Springham, S. V.; Rawat, R. S.; Lee, P.; Krishnan, M.

    2010-08-15

    Yttrium is presented as an absolute neutron detector for pulsed neutron sources. It has high sensitivity for detecting fast neutrons. Yttrium has the property of generating a monoenergetic secondary radiation in the form of a 909 keV gamma-ray caused by inelastic neutron interaction. It was calibrated numerically using MCNPX and does not need periodic recalibration. The total yttrium efficiency for detecting 2.45 MeV neutrons was determined to be f{sub n}{approx}4.1x10{sup -4} with an uncertainty of about 0.27%. The yttrium detector was employed in the NX2 plasma focus experiments and showed the neutron yield of the order of 10{sup 8} neutrons per discharge.

  7. Absolute geostrophic currents in global tropical oceans

    NASA Astrophysics Data System (ADS)

    Yang, Lina; Yuan, Dongliang

    2016-11-01

    A set of absolute geostrophic current (AGC) data for the period January 2004 to December 2012 are calculated using the P-vector method based on monthly gridded Argo profiles in the world tropical oceans. The AGCs agree well with altimeter geostrophic currents, Ocean Surface Current Analysis-Real time currents, and moored current-meter measurements at 10-m depth, based on which the classical Sverdrup circulation theory is evaluated. Calculations have shown that errors of wind stress calculation, AGC transport, and depth ranges of vertical integration cannot explain non-Sverdrup transport, which is mainly in the subtropical western ocean basins and equatorial currents near the Equator in each ocean basin (except the North Indian Ocean, where the circulation is dominated by monsoons). The identified non-Sverdrup transport is thereby robust and attributed to the joint effect of baroclinicity and relief of the bottom (JEBAR) and mesoscale eddy nonlinearity.

  8. Micron Accurate Absolute Ranging System: Range Extension

    NASA Technical Reports Server (NTRS)

    Smalley, Larry L.; Smith, Kely L.

    1999-01-01

    The purpose of this research is to investigate Fresnel diffraction as a means of obtaining absolute distance measurements with micron or greater accuracy. It is believed that such a system would prove useful to the Next Generation Space Telescope (NGST) as a non-intrusive, non-contact measuring system for use with secondary concentrator station-keeping systems. The present research attempts to validate past experiments and develop ways to apply the phenomena of Fresnel diffraction to micron accurate measurement. This report discusses past research on the phenomena, and the basis of the use Fresnel diffraction distance metrology. The apparatus used in the recent investigations, experimental procedures used, preliminary results are discussed in detail. Continued research and equipment requirements on the extension of the effective range of the Fresnel diffraction systems is also described.

  9. Absolute calibration of remote sensing instruments

    NASA Astrophysics Data System (ADS)

    Biggar, S. F.; Bruegge, C. J.; Capron, B. A.; Castle, K. R.; Dinguirard, M. C.; Holm, R. G.; Lingg, L. J.; Mao, Y.; Palmer, J. M.; Phillips, A. L.

    1985-12-01

    Source-based and detector-based methods for the absolute radiometric calibration of a broadband field radiometer are described. Using such a radiometer, calibrated by both methods, the calibration of the integrating sphere used in the preflight calibration of the Thematic Mapper was redetermined. The results are presented. The in-flight calibration of space remote sensing instruments is discussed. A method which uses the results of ground-based reflectance and atmospheric measurements as input to a radiative transfer code to predict the radiance at the instrument is described. A calibrated, helicopter-mounted radiometer is used to determine the radiance levels at intermediate altitudes to check the code predictions. Results of such measurements for the calibration of the Thematic Mapper on Landsat 5 and an analysis that shows the value of such measurements are described.

  10. Absolute radiometric calibration of the Thematic Mapper

    NASA Technical Reports Server (NTRS)

    Slater, P. N.; Biggar, S. F.; Holm, R. G.; Jackson, R. D.; Mao, Y.

    1986-01-01

    Calibration data for the solar reflective bands of the Landsat-5 TM obtained from five in-flight absolute radiometric calibrations from July 1984-November 1985 at White Sands, New Mexico are presented and analyzed. Ground reflectance and atmospheric data were utilized to predict the spectral radiance at the entrance pupil of the TM and the average number of digital counts in each TM band. The calibration of each of the TM solar reflective bands was calculated in terms of average digital counts/unit spectral radiance for each band. It is observed that for the 12 reflectance-based measurements the rms variation from the means as a percentage of the mean is + or - 1.9 percent; for the 11 measurements in the IR bands, it is + or - 3.4 percent; and the rms variation for all 23 measurements is + or - 2.8 percent.

  11. Swarm's Absolute Scalar Magnetometer metrological performances

    NASA Astrophysics Data System (ADS)

    Leger, J.; Fratter, I.; Bertrand, F.; Jager, T.; Morales, S.

    2012-12-01

    The Absolute Scalar Magnetometer (ASM) has been developed for the ESA Earth Observation Swarm mission, planned for launch in November 2012. As its Overhauser magnetometers forerunners flown on Oersted and Champ satellites, it will deliver high resolution scalar measurements for the in-flight calibration of the Vector Field Magnetometer manufactured by the Danish Technical University. Latest results of the ground tests carried out to fully characterize all parameters that may affect its accuracy, both at instrument and satellite level, will be presented. In addition to its baseline function, the ASM can be operated either at a much higher sampling rate (burst mode at 250 Hz) or in a dual mode where it also delivers vector field measurements as a by-product. The calibration procedure and the relevant vector performances will be discussed.

  12. MAGSAT: Vector magnetometer absolute sensor alignment determination

    NASA Technical Reports Server (NTRS)

    Acuna, M. H.

    1981-01-01

    A procedure is described for accurately determining the absolute alignment of the magnetic axes of a triaxial magnetometer sensor with respect to an external, fixed, reference coordinate system. The method does not require that the magnetic field vector orientation, as generated by a triaxial calibration coil system, be known to better than a few degrees from its true position, and minimizes the number of positions through which a sensor assembly must be rotated to obtain a solution. Computer simulations show that accuracies of better than 0.4 seconds of arc can be achieved under typical test conditions associated with existing magnetic test facilities. The basic approach is similar in nature to that presented by McPherron and Snare (1978) except that only three sensor positions are required and the system of equations to be solved is considerably simplified. Applications of the method to the case of the MAGSAT Vector Magnetometer are presented and the problems encountered discussed.

  13. Absolute size and proportionality characteristics of World Championship female basketball players.

    PubMed

    Ackland, T R; Schreiner, A B; Kerr, D A

    1997-10-01

    In total, 168 players from 14 national teams were measured using 38 anthropometric dimensions before the Women's World Basketball Championships held in Australia in 1994. Measures of segment length, breadth and girth were recorded by a team of trained anthropometrists using standard protocols. The subjects were divided according to playing position and team performance so that univariate analyses of variance could be administered using absolute size and proportionality data as dependent variables. Clear differences in absolute size were found between guards, forwards and centres, but in terms of proportionality the latter two groups exhibited some similarities, particularly for measures of relative size in upper body dimensions. With guards displaying a different proportionality profile from either forwards or centres, the various roles of each position within the team were considered to rationalize the findings.

  14. Ultra-low-frequency vertical vibration isolator based on a two-stage beam structure for absolute gravimetry

    NASA Astrophysics Data System (ADS)

    Wang, G.; Wu, K.; Hu, H.; Li, G.; Wang, L. J.

    2016-10-01

    To reduce seismic and environmental vibration noise, ultra-low-frequency vertical vibration isolation systems play an important role in absolute gravimetry. For this purpose, an isolator based on a two-stage beam structure is proposed and demonstrated. The isolator has a simpler and more robust structure than the present ultra-low-frequency vertical active vibration isolators. In the system, two beams are connected to a frame using flexural pivots. The upper beam is suspended from the frame with a normal hex spring and the lower beam is suspended from the upper one using a zero-length spring. The pivot of the upper beam is not vertically above the pivot of the lower beam. With this special design, the attachment points of the zero-length spring to the beams can be moved to adjust the effective stiffness. A photoelectric detector is used to detect the angle between the two beams, and a voice coil actuator attached to the upper beam is controlled by a feedback circuit to keep the angle at a fixed value. The system can achieve a natural period of 100 s by carefully moving the attachment points of the zero-length spring to the beams and tuning the feedback parameters. The system has been used as an inertial reference in the T-1 absolute gravimeter. The experiment results demonstrate that the system has significant vibration isolation performance that holds promise in applications such as absolute gravimeters.

  15. Seismic Q of the lunar upper mantle

    NASA Technical Reports Server (NTRS)

    Nakamura, Y.; Koyama, J.

    1982-01-01

    Shallow moonquake data are used to determine the frequency dependence of Q values for both compressional and shear waves in the upper mantle of the moon at frequencies between 3 and 8 Hz. The seismic P wave Q is estimated to be at least 4000 and is nearly independent of frequency or decreases slightly with increasing frequency, while the S wave Q increases from at least 4000 at 3 Hz to at least 7000 at 8 Hz. The rate of increase of Q(S) is approximately proportional to the 0.7 + or - 0.1 power of the frequency above 5 Hz. With the absence of other dissipation mechanisms, compressional heat loss may be a dominant factor in the lunar interior. Uncertainty remains, however, in the absolute values of Q's owing to the largely unknown detailed structure of the lunar upper mantle.

  16. Seismic Q of the lunar upper mantle

    NASA Astrophysics Data System (ADS)

    Nakamura, Y.; Koyama, J.

    1982-06-01

    Shallow moonquake data are used to determine the frequency dependence of Q values for both compressional and shear waves in the upper mantle of the moon at frequencies between 3 and 8 Hz. The seismic P wave Q is estimated to be at least 4000 and is nearly independent of frequency or decreases slightly with increasing frequency, while the S wave Q increases from at least 4000 at 3 Hz to at least 7000 at 8 Hz. The rate of increase of Q(S) is approximately proportional to the 0.7 + or - 0.1 power of the frequency above 5 Hz. With the absence of other dissipation mechanisms, compressional heat loss may be a dominant factor in the lunar interior. Uncertainty remains, however, in the absolute values of Q's owing to the largely unknown detailed structure of the lunar upper mantle.

  17. Absolute shielding scale for 31P from gas-phase NMR studies

    NASA Astrophysics Data System (ADS)

    Jameson, Cynthia J.; De Dios, Angel; Keith Jameson, A.

    1990-04-01

    Differences in the 31P nuclear shielding in the zero-pressure limit have been measured in seven compounds. An absolute 31P shielding scale based on the PH 3 molecular beam data is established and the absolute shielding of the standard liquid reference (85% aqueous H 3PO 4) is found to be 328.35 ppm, based on PH 3 being 594.45 ± 0.63 ppm. Comparisons with ab initio calculations show that calculations using local origins (the IGLO method) are in good agreement with experiment.

  18. A Novel Approach for Video-Based Absolute Navigation in Space Exploration Missions

    NASA Astrophysics Data System (ADS)

    Tadewos, Tadewos Getahun; Prinetto, Paolo; Rolfo, Daniele; Trotta, Pascal; Lanza, Piergiorgio; Martelli, Andrea; Tramutola, Antonio

    2014-08-01

    In the last years, Video-based Navigation is becoming an hot topic since camera sensors will be more and more included in future space exploration missions, to allow a visual comprehension of the surrounding unknown environment. This paper proposes a novel approach for Video-based Absolute Navigation focusing on the Entry, Descent and Landing phase of spacecrafts on planets. Moreover the paper shows how a Video-based Absolute Navigation processing chain can exploit Field Programmable Gate Array (FPGA) devices to achieve high throughput, in terms of frames-per-seconds. Experimental results highlight the robustness and limited memory requirements of the proposed approach.

  19. Upper Lid Blepharoplasty.

    PubMed

    Hahn, Samuel; Holds, John B; Couch, Steven M

    2016-05-01

    Upper lid blepharoplasty is a common procedure for restoration and rejuvenation of the upper eyelids that can be performed safely and reliably. Understanding the anatomy and aging process of the brow-upper lid aesthetic unit along with properly assessing the excesses and deficiencies of the periorbital region helps to formulate an appropriate surgical plan. Volume deficiency in the aging upper lid may require corrective augmentation. Preexisting asymmetries and ptosis need to be identified and discussed before surgery. Standardized photography along with a candid discussion regarding patients' desired outcomes and realistic expectations are essential to a successful outcome. PMID:27105797

  20. Comparison of Upper Tropospheric Water Vapor from AIRS and Cryogenic Frostpoint Hygrometers

    NASA Technical Reports Server (NTRS)

    Fetzer, Eric J.; Vomel, Holger

    2004-01-01

    Upper tropospheric water vapor (UTWV) from the Atmospheric Infrared Sounder (AIRS) experiment on NASA's Aqua spacecraft has the potential of addressing several important climate questions. The specified AIRS system measurement uncertainty for water vapor is 20 percent absolute averaged over 2 km layers. Cryogenic frostpoint hygrometers (CFH) are balloon-borne water vapor sensors responsive from the surface into the lower stratosphere. Several dozen coincident, collocated CFH profiles have been obtained for AlRS validation. The combination of CFH sensitivity and sample size offers a statistically compelling picture of AIRS UTWV measurement capability. We present a comparison between CFH observations and AlRS retrievals. We focus on the altitude range from the middle troposphere up to heights at the limits of AlRS sensitivity to water vapor, believed to be around 100-1 50 hPa.

  1. Application of the Absolute Nodal Co-Ordinate Formulation to Multibody System Dynamics

    NASA Astrophysics Data System (ADS)

    Escalona, J. L.; Hussien, H. A.; Shabana, A. A.

    1998-07-01

    The floating frame of reference formulation is currently the most widely used approach in flexible multibody simulations. The use of this approach, however, has been limited to small deformation problems. In this investigation, the computer implementation of the newabsolute nodal co-ordinate formulationand its use in the small and large deformation analysis of flexible multibody systems that consist of interconnected bodies are discussed. While in the floating frame of reference formulation a mixed set of absolute reference and local elastic co-ordinates are used, in the absolute nodal co-ordinate formulation only absolute co-ordinates are used. In the absolute nodal co-ordinate formulation, new interpretation of the nodal co-ordinates of the finite elements is used. No infinitesimal or finite rotations are used as nodal co-ordinates from beams and plates, instead, global slopes are used to define the element nodal co-ordinates. Using this interpretation of the element co-ordinates, beams and plates can be considered as isoparametric elements, and as a result, exact modelling of the rigid body dynamics can be obtained using the element shape function and the absolute nodal co-ordinates. Unlike the floating frame of reference approach, no co-ordinate transformation is required in order to determine the element inertia. The mass matrix of the finite elements is a constant matrix, and therefore, the centrifugal and Coriolis forces are equal to zero when the absolute nodal co-ordinate formulation is used. Another advantage of using the absolute nodal co-ordinate formulation in the dynamic simulation of multibody systems is its simplicity in imposing some of the joint constraints and also its simplicity in formulating the generalized forces due to spring-damper elements. The results obtained in this investigation show an excellent agreement with the results obtained using the floating frame of reference formulation when large rotation-small deformation problems are

  2. Absolute Dating of Desert Varnish Using Portable X-Ray Fluorescence: Calibration and Testing

    NASA Astrophysics Data System (ADS)

    Pingitore, N. E.; Lytle, F. W.; Rowley, P. D.; Ferris, D. E.

    2004-12-01

    Desert varnish, also called rock varnish, is a thin biogenic layer of Mn-oxides, Fe-oxides, and clays that coats rock surfaces in arid and semi-arid regions. The mass of these metals in the varnish registers cumulative biologic activity over time and presents a possible dating mechanism, subject to appropriate assumptions and restrictions. We have used a portable x-ray fluorescence (PXRF) unit to measure Mn and Fe in numerous desert varnishes, both in the field and laboratory; the anticipated relationship between age and mass emerges from these data. Our attempts to refine the PXRF technique for absolute dating of desert varnish are confounded by the limited number of "dated" varnishes available to calibrate and test the method. Although there is no current method to directly ascertain the age of desert varnish, our search for "dated" varnishes has yielded three suitable types of test materials: (1) The ages of young basalt flows dated by various K/Ar radiometric techniques represent the maximum age of varnish developed on those surfaces. Such rocks are useful in the time range of perhaps 250,000 to 10,000 years; surface spalling with loss of varnish presents an upper time limit and difficulty in dating Holocene basalts presents a lower limit. Basalt flows typically provide horizontal surfaces that are ideal for PXRF measurements because, as a biogenic process, varnish development even at a single site varies with solar orientation. (2) Petroglyphs are the rock art that native peoples produced by pecking away varnish to expose fresh rock. This process restarts varnish development and the pecked surface gradually repatinates over time. At some locales, certain figures, symbols, and stylistic elements can be associated with an archaeological culture of known antiquity and duration, thus providing an age range for such glyphs. In the desert Southwest and Great Basin of the United States, appropriate glyphs are known from the present to at least 7000 years BP. Many of

  3. An Adaptive TVD Limiter

    NASA Astrophysics Data System (ADS)

    Jeng, Yih Nen; Payne, Uon Jan

    1995-05-01

    An adaptive TVD limiter, based on a limiter approximating the upper boundary of the TVD range and that of the third-order upwind TVD scheme, is developed in this work. The limiter switches to the comprressive limiter near a discontinuity, to the third-order TVD scheme's limiter in the smooth region, and to a weighted averaged scheme in the transition region between smooth and high gradient solutions. Numerical experiments show that the proposed scheme works very well for one-dimensional scalar equation problems but becomes less effective in one- and two-dimensional Euler equation problems. Further study is required for the two-dimensional scalar equation problems.

  4. Noninvasive absolute cerebral oximetry with frequency-domain near-infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Hallacoglu, Bertan

    Near-infrared spectroscopy (NIRS) measurements of absolute concentrations of oxy-hemoglobin and deoxy-hemoglobin in the human brain can provide critical information about cerebral physiology in terms of cerebral blood volume, blood flow, oxygen delivery, and metabolic rate of oxygen. We developed several frequency domain NIRS data acquisition and analysis methods aimed at absolute measurements of hemoglobin concentration and saturation in cerebral tissue of adult human subjects. Extensive experimental investigations were carried out in various homogenous and two-layered tissue-mimicking phantoms, and biological tissues. The advantages and limitations of commonly used homogenous models and inversion strategies were thoroughly investigated. Prior to human subjects, extensive studies were carried out in in vivo animal models. In rabbits, absolute hemoglobin oxygen desaturation was shown to depend strongly on surgically induced testicular torsion. Methods developed in this study were then adapted for measurements in the rat brain. Absolute values were demonstrated to discern cerebrovascular impairment in a rat model of diet-induced vascular cognitive impairment. These results facilitated the development of clinically useful optical measures of cerebrovascular health. In a large group of human subjects, employing a homogeneous model for absolute measurements was shown to be reliable and robust. However, it was also shown to be limited due to the relatively thick extracerebral tissue. The procedure we develop in this work and the thesis thereof performs a nonlinear inversion procedure with six unknown parameters with no other prior knowledge for the retrieval of the optical coefficients and top layer thickness with high accuracy on two-layered media. Our absolute measurements of cerebral hemoglobin concentration and saturation are based on the discrimination of extracerebral and cerebral tissue layers, and they can enhance the impact of NIRS for cerebral hemodynamics and

  5. On the absolute alignment of GONG images

    NASA Astrophysics Data System (ADS)

    Toner, C. G.

    2001-01-01

    In order to combine data from the six instruments in the GONG network the alignment of all of the images must be known to a fairly high precision (~0°.1 for GONG Classic and ~0°.01 for GONG+). The relative orientation is obtained using the angular cross-correlation method described by (Toner & Harvey, 1998). To obtain the absolute orientation the Project periodically records a day of drift scans, where the image of the Sun is allowed to drift across the CCD repeatedly throughout the day. These data are then analyzed to deduce the direction of Terrestrial East-West as a function of hour angle (i.e., time) for that instrument. The transit of Mercury on Nov. 15, 1999, which was recorded by three of the GONG instruments, provided an independent check on the current alignment procedures. Here we present a comparison of the alignment of GONG images as deduced from both drift scans and the Mercury transit for two GONG sites: Tucson (GONG+ camera) and Mauna Loa (GONG Classic camera). The agreement is within ~0°.01 for both cameras, however, the scatter is substantially larger for GONG Classic: ~0°.03 compared to ~0°.01 for GONG+.

  6. Climate Absolute Radiance and Refractivity Observatory (CLARREO)

    NASA Technical Reports Server (NTRS)

    Leckey, John P.

    2015-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) is a mission, led and developed by NASA, that will measure a variety of climate variables with an unprecedented accuracy to quantify and attribute climate change. CLARREO consists of three separate instruments: an infrared (IR) spectrometer, a reflected solar (RS) spectrometer, and a radio occultation (RO) instrument. The mission will contain orbiting radiometers with sufficient accuracy, including on orbit verification, to calibrate other space-based instrumentation, increasing their respective accuracy by as much as an order of magnitude. The IR spectrometer is a Fourier Transform spectrometer (FTS) working in the 5 to 50 microns wavelength region with a goal of 0.1 K (k = 3) accuracy. The FTS will achieve this accuracy using phase change cells to verify thermistor accuracy and heated halos to verify blackbody emissivity, both on orbit. The RS spectrometer will measure the reflectance of the atmosphere in the 0.32 to 2.3 microns wavelength region with an accuracy of 0.3% (k = 2). The status of the instrumentation packages and potential mission options will be presented.

  7. Absolute flux measurements for swift atoms

    NASA Technical Reports Server (NTRS)

    Fink, M.; Kohl, D. A.; Keto, J. W.; Antoniewicz, P.

    1987-01-01

    While a torsion balance in vacuum can easily measure the momentum transfer from a gas beam impinging on a surface attached to the balance, this measurement depends on the accommodation coefficients of the atoms with the surface and the distribution of the recoil. A torsion balance is described for making absolute flux measurements independent of recoil effects. The torsion balance is a conventional taut suspension wire design and the Young modulus of the wire determines the relationship between the displacement and the applied torque. A compensating magnetic field is applied to maintain zero displacement and provide critical damping. The unique feature is to couple the impinging gas beam to the torsion balance via a Wood's horn, i.e., a thin wall tube with a gradual 90 deg bend. Just as light is trapped in a Wood's horn by specular reflection from the curved surfaces, the gas beam diffuses through the tube. Instead of trapping the beam, the end of the tube is open so that the atoms exit the tube at 90 deg to their original direction. Therefore, all of the forward momentum of the gas beam is transferred to the torsion balance independent of the angle of reflection from the surfaces inside the tube.

  8. Issues in Absolute Spectral Radiometric Calibration: Intercomparison of Eight Sources

    NASA Technical Reports Server (NTRS)

    Goetz, Alexander F. H.; Kindel, Bruce; Pilewskie, Peter

    1998-01-01

    The application of atmospheric models to AVIRIS and other spectral imaging data to derive surface reflectance requires that the sensor output be calibrated to absolute radiance. Uncertainties in absolute calibration are to be expected, and claims of 92% accuracy have been published. Measurements of accurate surface albedos and cloud absorption to be used in radiative balance calculations depend critically on knowing the absolute spectral-radiometric response of the sensor. The Earth Observing System project is implementing a rigorous program of absolute radiometric calibration for all optical sensors. Since a number of imaging instruments that provide output in terms of absolute radiance are calibrated at different sites, it is important to determine the errors that can be expected among calibration sites. Another question exists about the errors in the absolute knowledge of the exoatmospheric spectral solar irradiance.

  9. Improved upper limits on B(K{sub L}{sup 0} {r_arrow} {mu}e) and B(K{sub L}{sup 0} {r_arrow} ee) and a new value for B(K{sub L}{sup 0} {r_arrow} {mu}{mu})

    SciTech Connect

    Molzon, W.R.

    1998-09-01

    The author gives recent results from E791 at BNL with improved upper limits on the branching fractions B(K{sub L}{sup 0} {r_arrow} {mu}e) and B(K{sub L}{sup 0} {r_arrow} ee) of 8.5 {times} 10{sup {minus}11} and 11.6 {times} 10{sup {minus}11} at 90% C.L. He also gives a preliminary result of a new measurement B(K{sub L}{sup 0} {r_arrow} {mu}{mu}) = 7.6 {+-} 0.5(stat) {+-} 0.4(syst) {times} 10{sup {minus}9}.

  10. Absolute nuclear material assay using count distribution (LAMBDA) space

    SciTech Connect

    Prasad, Mano K.; Snyderman, Neal J.; Rowland, Mark S.

    2015-12-01

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  11. Absolute nuclear material assay using count distribution (LAMBDA) space

    DOEpatents

    Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.

    2012-06-05

    A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

  12. Antifungal activity of tuberose absolute and some of its constituents.

    PubMed

    Nidiry, Eugene Sebastian J; Babu, C S Bujji

    2005-05-01

    The antifungal activity of the absolute of tuberose (Polianthes tuberosa ) and some of its constituents were evaluated against the mycelial growth of Colletotrichum gloeosporioides on potato-dextrose-agar medium. Tuberose absolute showed only mild activity at a concentration of 500 mg/L. However, three constituents present in the absolute, namely geraniol, indole and methyl anthranilate exhibited significant activity showing total inhibition of the mycelial growth at this concentration.

  13. The absolute disparity anomaly and the mechanism of relative disparities.

    PubMed

    Chopin, Adrien; Levi, Dennis; Knill, David; Bavelier, Daphne

    2016-06-01

    There has been a long-standing debate about the mechanisms underlying the perception of stereoscopic depth and the computation of the relative disparities that it relies on. Relative disparities between visual objects could be computed in two ways: (a) using the difference in the object's absolute disparities (Hypothesis 1) or (b) using relative disparities based on the differences in the monocular separations between objects (Hypothesis 2). To differentiate between these hypotheses, we measured stereoscopic discrimination thresholds for lines with different absolute and relative disparities. Participants were asked to judge the depth of two lines presented at the same distance from the fixation plane (absolute disparity) or the depth between two lines presented at different distances (relative disparity). We used a single stimulus method involving a unique memory component for both conditions, and no extraneous references were available. We also measured vergence noise using Nonius lines. Stereo thresholds were substantially worse for absolute disparities than for relative disparities, and the difference could not be explained by vergence noise. We attribute this difference to an absence of conscious readout of absolute disparities, termed the absolute disparity anomaly. We further show that the pattern of correlations between vergence noise and absolute and relative disparity acuities can be explained jointly by the existence of the absolute disparity anomaly and by the assumption that relative disparity information is computed from absolute disparities (Hypothesis 1).

  14. The absolute disparity anomaly and the mechanism of relative disparities

    PubMed Central

    Chopin, Adrien; Levi, Dennis; Knill, David; Bavelier, Daphne

    2016-01-01

    There has been a long-standing debate about the mechanisms underlying the perception of stereoscopic depth and the computation of the relative disparities that it relies on. Relative disparities between visual objects could be computed in two ways: (a) using the difference in the object's absolute disparities (Hypothesis 1) or (b) using relative disparities based on the differences in the monocular separations between objects (Hypothesis 2). To differentiate between these hypotheses, we measured stereoscopic discrimination thresholds for lines with different absolute and relative disparities. Participants were asked to judge the depth of two lines presented at the same distance from the fixation plane (absolute disparity) or the depth between two lines presented at different distances (relative disparity). We used a single stimulus method involving a unique memory component for both conditions, and no extraneous references were available. We also measured vergence noise using Nonius lines. Stereo thresholds were substantially worse for absolute disparities than for relative disparities, and the difference could not be explained by vergence noise. We attribute this difference to an absence of conscious readout of absolute disparities, termed the absolute disparity anomaly. We further show that the pattern of correlations between vergence noise and absolute and relative disparity acuities can be explained jointly by the existence of the absolute disparity anomaly and by the assumption that relative disparity information is computed from absolute disparities (Hypothesis 1). PMID:27248566

  15. Upper critical field of copper molybdenum sulfide

    NASA Technical Reports Server (NTRS)

    Alterovitz, S. A.; Woollam, J. A.

    1978-01-01

    The upper critical field of sintered and sputtered copper molybdenum sulfide Cu(x)Mo6S8 was measured and found to exceed the Werthamer, Helfand, and Hohenberg (1966) value for a type II superconductor characterized by dirty limit, weak isotropic electron phonon coupling, and no paramagnetic limiting. It is suggested that the enhancement results from anisotropy or clean limit or both. Other ternary molybdenum sulfides appear to show similar anomalies.

  16. Evaluation of the Absolute Regional Temperature Potential

    NASA Technical Reports Server (NTRS)

    Shindell, D. T.

    2012-01-01

    The Absolute Regional Temperature Potential (ARTP) is one of the few climate metrics that provides estimates of impacts at a sub-global scale. The ARTP presented here gives the time-dependent temperature response in four latitude bands (90-28degS, 28degS-28degN, 28-60degN and 60-90degN) as a function of emissions based on the forcing in those bands caused by the emissions. It is based on a large set of simulations performed with a single atmosphere-ocean climate model to derive regional forcing/response relationships. Here I evaluate the robustness of those relationships using the forcing/response portion of the ARTP to estimate regional temperature responses to the historic aerosol forcing in three independent climate models. These ARTP results are in good accord with the actual responses in those models. Nearly all ARTP estimates fall within +/-20%of the actual responses, though there are some exceptions for 90-28degS and the Arctic, and in the latter the ARTP may vary with forcing agent. However, for the tropics and the Northern Hemisphere mid-latitudes in particular, the +/-20% range appears to be roughly consistent with the 95% confidence interval. Land areas within these two bands respond 39-45% and 9-39% more than the latitude band as a whole. The ARTP, presented here in a slightly revised form, thus appears to provide a relatively robust estimate for the responses of large-scale latitude bands and land areas within those bands to inhomogeneous radiative forcing and thus potentially to emissions as well. Hence this metric could allow rapid evaluation of the effects of emissions policies at a finer scale than global metrics without requiring use of a full climate model.

  17. Absolute Radiometric Calibration of KOMPSAT-3A

    NASA Astrophysics Data System (ADS)

    Ahn, H. Y.; Shin, D. Y.; Kim, J. S.; Seo, D. C.; Choi, C. U.

    2016-06-01

    This paper presents a vicarious radiometric calibration of the Korea Multi-Purpose Satellite-3A (KOMPSAT-3A) performed by the Korea Aerospace Research Institute (KARI) and the Pukyong National University Remote Sensing Group (PKNU RSG) in 2015.The primary stages of this study are summarized as follows: (1) A field campaign to determine radiometric calibrated target fields was undertaken in Mongolia and South Korea. Surface reflectance data obtained in the campaign were input to a radiative transfer code that predicted at-sensor radiance. Through this process, equations and parameters were derived for the KOMPSAT-3A sensor to enable the conversion of calibrated DN to physical units, such as at-sensor radiance or TOA reflectance. (2) To validate the absolute calibration coefficients for the KOMPSAT-3A sensor, we performed a radiometric validation with a comparison of KOMPSAT-3A and Landsat-8 TOA reflectance using one of the six PICS (Libya 4). Correlations between top-of-atmosphere (TOA) radiances and the spectral band responses of the KOMPSAT-3A sensors at the Zuunmod, Mongolia and Goheung, South Korea sites were significant for multispectral bands. The average difference in TOA reflectance between KOMPSAT-3A and Landsat-8 image over the Libya 4, Libya site in the red-green-blue (RGB) region was under 3%, whereas in the NIR band, the TOA reflectance of KOMPSAT-3A was lower than the that of Landsat-8 due to the difference in the band passes of two sensors. The KOMPSAT-3Aensor includes a band pass near 940 nm that can be strongly absorbed by water vapor and therefore displayed low reflectance. Toovercome this, we need to undertake a detailed analysis using rescale methods, such as the spectral bandwidth adjustment factor.

  18. Orion Absolute Navigation System Progress and Challenge

    NASA Technical Reports Server (NTRS)

    Holt, Greg N.; D'Souza, Christopher

    2012-01-01

    The absolute navigation design of NASA's Orion vehicle is described. It has undergone several iterations and modifications since its inception, and continues as a work-in-progress. This paper seeks to benchmark the current state of the design and some of the rationale and analysis behind it. There are specific challenges to address when preparing a timely and effective design for the Exploration Flight Test (EFT-1), while still looking ahead and providing software extensibility for future exploration missions. The primary onboard measurements in a Near-Earth or Mid-Earth environment consist of GPS pseudo-range and delta-range, but for future explorations missions the use of star-tracker and optical navigation sources need to be considered. Discussions are presented for state size and composition, processing techniques, and consider states. A presentation is given for the processing technique using the computationally stable and robust UDU formulation with an Agee-Turner Rank-One update. This allows for computational savings when dealing with many parameters which are modeled as slowly varying Gauss-Markov processes. Preliminary analysis shows up to a 50% reduction in computation versus a more traditional formulation. Several state elements are discussed and evaluated, including position, velocity, attitude, clock bias/drift, and GPS measurement biases in addition to bias, scale factor, misalignment, and non-orthogonalities of the accelerometers and gyroscopes. Another consideration is the initialization of the EKF in various scenarios. Scenarios such as single-event upset, ground command, and cold start are discussed as are strategies for whole and partial state updates as well as covariance considerations. Strategies are given for dealing with latent measurements and high-rate propagation using multi-rate architecture. The details of the rate groups and the data ow between the elements is discussed and evaluated.

  19. Absolute determination of local tropospheric OH concentrations

    NASA Technical Reports Server (NTRS)

    Armerding, Wolfgang; Comes, Franz-Josef

    1994-01-01

    Long path absorption (LPA) according to Lambert Beer's law is a method to determine absolute concentrations of trace gases such as tropospheric OH. We have developed a LPA instrument which is based on a rapid tuning of the light source which is a frequency doubled dye laser. The laser is tuned across two or three OH absorption features around 308 nm with a scanning speed of 0.07 cm(exp -1)/microsecond and a repetition rate of 1.3 kHz. This high scanning speed greatly reduces the fluctuation of the light intensity caused by the atmosphere. To obtain the required high sensitivity the laser output power is additionally made constant and stabilized by an electro-optical modulator. The present sensitivity is of the order of a few times 10(exp 5) OH per cm(exp 3) for an acquisition time of a minute and an absorption path length of only 1200 meters so that a folding of the optical path in a multireflection cell was possible leading to a lateral dimension of the cell of a few meters. This allows local measurements to be made. Tropospheric measurements have been carried out in 1991 resulting in the determination of OH diurnal variation at specific days in late summer. Comparison with model calculations have been made. Interferences are mainly due to SO2 absorption. The problem of OH self generation in the multireflection cell is of minor extent. This could be shown by using different experimental methods. The minimum-maximum signal to noise ratio is about 8 x 10(exp -4) for a single scan. Due to the small size of the absorption cell the realization of an open air laboratory is possible in which by use of an additional UV light source or by additional fluxes of trace gases the chemistry can be changed under controlled conditions allowing kinetic studies of tropospheric photochemistry to be made in open air.

  20. [Upper extremity arterial diseases].

    PubMed

    Becker, F

    2007-02-01

    Compared to lower limb arterial diseases, upper limb arterial diseases look rare, heterogeneous with various etiologies and a rather vague clinical picture, but with a negligible risk of amputation. Almost all types of arterial diseases can be present in the upper limb, but the anatomical and hemodynamic conditions particular to the upper limb often confuse the issue. Thus, atherosclerosis affects mainly the subclavian artery in its proximal segment where the potential of collateral pathway is high making the symptomatic forms not very frequent whereas the prevalence of subclavian artery stenosis or occlusion is relatively high. The clinical examination and the etiologies are discussed according to the clinical, anatomical and hemodynamic context.

  1. Absolute photoabsorption cross sections of Sr I from the 5s ionization threshold to the 5p threshold

    NASA Astrophysics Data System (ADS)

    Chu, C. C.; Fung, H. S.; Wu, H. H.; Yih, T. S.

    1998-09-01

    We have measured the absolute photoabsorption cross sections of Sr I from its 5s ionization threshold up to the 0953-4075/31/17/010/img1 thresholds. The spectrum includes the Sr I 0953-4075/31/17/010/img2, 0953-4075/31/17/010/img3, 0953-4075/31/17/010/img4 and 0953-4075/31/17/010/img5 doubly excited series which converge to the 0953-4075/31/17/010/img6 or 0953-4075/31/17/010/img1 series limits. Synchrotron radiation, from the 1 m Seya-Namioka beam line of the Synchrotron Radiation Research Center at Hsin-Chu, Taiwan, was used as the background continuum. The absolute column density was determined by measuring simultaneously the temperature distribution profiles and the total pressure in a heatpipe. Absolute cross sections were obtained using the Beer-Lambert law. The measured absolute cross section for the 5s ionization threshold was 0953-4075/31/17/010/img8. At the most significant autoionizing resonance, 0953-4075/31/17/010/img9 around 0953-4075/31/17/010/img10, the absolute cross section was measured as 0953-4075/31/17/010/img11. The absolute cross sections presented here are larger than those based on saturated vapour-pressure data, and less than those based on the f-value measurements. All the absolute cross sections in this work are compared with both recent experiments and

  2. Mid-infrared absolute spectral responsivity scale based on an absolute cryogenic radiometer and an optical parametric oscillator laser

    NASA Astrophysics Data System (ADS)

    Zhao, Kun; Shi, Xueshun; Chen, Haidong; Liu, Yulong; Liu, Changming; Chen, Kunfeng; Li, Ligong; Gan, Haiyong; Ma, Chong

    2016-06-01

    We are reporting on a laser-based absolute spectral responsivity scale in the mid-infrared spectral range. By using a mid-infrared tunable optical parametric oscillator as the laser source, the absolute responsivity scale has been established by calibrating thin-film thermopile detectors against an absolute cryogenic radiometer. The thin-film thermopile detectors can be then used as transfer standard detectors. The extended uncertainty of the absolute spectral responsivity measurement has been analyzed to be 0.58%–0.68% (k  =  2).

  3. Mid-infrared absolute spectral responsivity scale based on an absolute cryogenic radiometer and an optical parametric oscillator laser

    NASA Astrophysics Data System (ADS)

    Zhao, Kun; Shi, Xueshun; Chen, Haidong; Liu, Yulong; Liu, Changming; Chen, Kunfeng; Li, Ligong; Gan, Haiyong; Ma, Chong

    2016-06-01

    We are reporting on a laser-based absolute spectral responsivity scale in the mid-infrared spectral range. By using a mid-infrared tunable optical parametric oscillator as the laser source, the absolute responsivity scale has been established by calibrating thin-film thermopile detectors against an absolute cryogenic radiometer. The thin-film thermopile detectors can be then used as transfer standard detectors. The extended uncertainty of the absolute spectral responsivity measurement has been analyzed to be 0.58%-0.68% (k  =  2).

  4. The upper atmosphere of Uranus

    NASA Technical Reports Server (NTRS)

    Strobel, Darrell F.; Yelle, Roger V.; Shemansky, Donald E.; Atreya, Sushil K.

    1991-01-01

    Voyager measurements of the upper atmosphere of Uranus are analyzed and developed. The upper atmosphere of Uranus is predominantly H2, with at most 10 percent He by volume, and the dominant constituent of the exosphere is H. The thermosphere is warm, with an asymptotic isothermal temperature of about 800 K. Atomic hydrogen at this temperature forms an extensive thermal corona and creates gas drag that severely limits the lifetime of small ring particles. The upper atmosphere emits copious amounts of UV radiation from pressures greater than 0.01 microbar. The depth of this emission level imposes a powerful constraint on permissible emission mechanisms. Electron excitation from a thin layer near the exobase appears to violate this constraint. Solar fluorescence is consistent with the observed trend in solar zenith-angle variation of the emissions and is absent from the night side of the planet. On Uranus, it accounts for the observed Lyman beta to H2 bands intensity ratio and an important fraction of the observed intensity (about 55 percent).

  5. Upper limb prostheses.

    PubMed

    Bogucki, A

    2001-04-30

    This article discusses the technical and medical difficulties involved in managing prostheses of the upper limb. The level of amputation governs the type of prosthesis construction chosen, but does not affect emotional acceptance. The factors determining therapeutic success include the quality of the stump, the skill involved in prosthetic socket fabrication, and the proper selection of modular components, as well as good rehabilitation and professional care for the patient with amputated upper limb. PMID:17987000

  6. Observables sensitive to absolute neutrino masses. II

    SciTech Connect

    Fogli, G. L.; Marrone, A.; Rotunno, A. M.; Lisi, E.; Melchiorri, A.; Palazzo, A.; Silk, J.; Slosar, A.

    2008-08-01

    In this followup to Phys. Rev. D 75, 053001 (2007) , we report updated constraints on neutrino mass-mixing parameters, in light of recent neutrino oscillation data (KamLAND, SNO, and MINOS) and cosmological observations (WMAP 5-year and other data). We discuss their interplay with the final 0{nu}2{beta} decay results in {sup 76}Ge claimed by part of the Heidelberg-Moscow Collaboration, using recent evaluations of the corresponding nuclear matrix elements, and their uncertainties. We also comment on the 0{nu}2{beta} limits in {sup 130}Te recently set by Cuoricino and on prospective limits or signals from the Karlsruhe tritium neutrino experiment.

  7. Robust control design with real parameter uncertainty using absolute stability theory. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    How, Jonathan P.; Hall, Steven R.

    1993-01-01

    The purpose of this thesis is to investigate an extension of mu theory for robust control design by considering systems with linear and nonlinear real parameter uncertainties. In the process, explicit connections are made between mixed mu and absolute stability theory. In particular, it is shown that the upper bounds for mixed mu are a generalization of results from absolute stability theory. Both state space and frequency domain criteria are developed for several nonlinearities and stability multipliers using the wealth of literature on absolute stability theory and the concepts of supply rates and storage functions. The state space conditions are expressed in terms of Riccati equations and parameter-dependent Lyapunov functions. For controller synthesis, these stability conditions are used to form an overbound of the H2 performance objective. A geometric interpretation of the equivalent frequency domain criteria in terms of off-axis circles clarifies the important role of the multiplier and shows that both the magnitude and phase of the uncertainty are considered. A numerical algorithm is developed to design robust controllers that minimize the bound on an H2 cost functional and satisfy an analysis test based on the Popov stability multiplier. The controller and multiplier coefficients are optimized simultaneously, which avoids the iteration and curve-fitting procedures required by the D-K procedure of mu synthesis. Several benchmark problems and experiments on the Middeck Active Control Experiment at M.I.T. demonstrate that these controllers achieve good robust performance and guaranteed stability bounds.

  8. Ridge-spotting: A new test for Pacific absolute plate motion models

    NASA Astrophysics Data System (ADS)

    Wessel, Paul; Müller, R. Dietmar

    2016-06-01

    Relative plate motions provide high-resolution descriptions of motions of plates relative to other plates. Yet geodynamically, motions of plates relative to the mantle are required since such motions can be attributed to forces (e.g., slab pull and ridge push) acting upon the plates. Various reference frames have been proposed, such as the hot spot reference frame, to link plate motions to a mantle framework. Unfortunately, both accuracy and precision of absolute plate motion models lag behind those of relative plate motion models. Consequently, it is paramount to use relative plate motions in improving our understanding of absolute plate motions. A new technique called "ridge-spotting" combines absolute and relative plate motions and examines the viability of proposed absolute plate motion models. We test the method on six published Pacific absolute plate motions models, including fixed and moving hot spot models as well as a geodynamically derived model. Ridge-spotting reconstructs the Pacific-Farallon and Pacific-Antarctica ridge systems over the last 80 Myr. All six absolute plate motion models predict large amounts of northward migration and monotonic clockwise rotation for the Pacific-Farallon ridge. A geodynamic implication of our ridge migration predictions is that the suggestion that the Pacific-Farallon ridge may have been pinned by a large mantle upwelling is not supported. Unexpected or erratic ridge behaviors may be tied to limitations in the models themselves or (for Indo-Atlantic models) discrepancies in the plate circuits used to project models into the Pacific realm. Ridge-spotting is promising and will be extended to include more plates and other ocean basins.

  9. Novalis' Poetic Uncertainty: A "Bildung" with the Absolute

    ERIC Educational Resources Information Center

    Mika, Carl

    2016-01-01

    Novalis, the Early German Romantic poet and philosopher, had at the core of his work a mysterious depiction of the "absolute." The absolute is Novalis' name for a substance that defies precise knowledge yet calls for a tentative and sensitive speculation. How one asserts a truth, represents an object, and sets about encountering things…

  10. Absolute Pitch in Infant Auditory Learning: Evidence for Developmental Reorganization.

    ERIC Educational Resources Information Center

    Saffran, Jenny R.; Griepentrog, Gregory J.

    2001-01-01

    Two experiments examined 8-month-olds' use of absolute and relative pitch cues in a tone-sequence statistical learning task. Results suggest that, given unsegmented stimuli that do not conform to rules of musical composition, infants are more likely to track patterns of absolute pitches than of relative pitches. A third experiment found that adult…

  11. Supplementary and Enrichment Series: Absolute Value. Teachers' Commentary. SP-25.

    ERIC Educational Resources Information Center

    Bridgess, M. Philbrick, Ed.

    This is one in a series of manuals for teachers using SMSG high school supplementary materials. The pamphlet includes commentaries on the sections of the student's booklet, answers to the exercises, and sample test questions. Topics covered include addition and multiplication in terms of absolute value, graphs of absolute value in the Cartesian…

  12. Supplementary and Enrichment Series: Absolute Value. SP-24.

    ERIC Educational Resources Information Center

    Bridgess, M. Philbrick, Ed.

    This is one in a series of SMSG supplementary and enrichment pamphlets for high school students. This series is designed to make material for the study of topics of special interest to students readily accessible in classroom quantity. Topics covered include absolute value, addition and multiplication in terms of absolute value, graphs of absolute…

  13. Absolute dimensions of unevolved O type close binaries

    SciTech Connect

    Doom, C.; de Loore, C.

    1984-03-15

    A method is presented to derive the absolute dimensions of early-type detached binaries by combining the observed parameters with results of evolutionary computations. The method is used to obtain the absolute dimensions of nine close binaries. We find that most systems have an initial masss ratio near 1.

  14. Absolute Humidity and the Seasonality of Influenza (Invited)

    NASA Astrophysics Data System (ADS)

    Shaman, J. L.; Pitzer, V.; Viboud, C.; Grenfell, B.; Goldstein, E.; Lipsitch, M.

    2010-12-01

    Much of the observed wintertime increase of mortality in temperate regions is attributed to seasonal influenza. A recent re-analysis of laboratory experiments indicates that absolute humidity strongly modulates the airborne survival and transmission of the influenza virus. Here we show that the onset of increased wintertime influenza-related mortality in the United States is associated with anomalously low absolute humidity levels during the prior weeks. We then use an epidemiological model, in which observed absolute humidity conditions temper influenza transmission rates, to successfully simulate the seasonal cycle of observed influenza-related mortality. The model results indicate that direct modulation of influenza transmissibility by absolute humidity alone is sufficient to produce this observed seasonality. These findings provide epidemiological support for the hypothesis that absolute humidity drives seasonal variations of influenza transmission in temperate regions. In addition, we show that variations of the basic and effective reproductive numbers for influenza, caused by seasonal changes in absolute humidity, are consistent with the general timing of pandemic influenza outbreaks observed for 2009 A/H1N1 in temperate regions. Indeed, absolute humidity conditions correctly identify the region of the United States vulnerable to a third, wintertime wave of pandemic influenza. These findings suggest that the timing of pandemic influenza outbreaks is controlled by a combination of absolute humidity conditions, levels of susceptibility and changes in population mixing and contact rates.

  15. Determination of Absolute Zero Using a Computer-Based Laboratory

    ERIC Educational Resources Information Center

    Amrani, D.

    2007-01-01

    We present a simple computer-based laboratory experiment for evaluating absolute zero in degrees Celsius, which can be performed in college and undergraduate physical sciences laboratory courses. With a computer, absolute zero apparatus can help demonstrators or students to observe the relationship between temperature and pressure and use…

  16. Constraining absolute neutrino masses via detection of galactic supernova neutrinos at JUNO

    SciTech Connect

    Lu, Jia-Shu; Cao, Jun; Li, Yu-Feng; Zhou, Shun

    2015-05-26

    A high-statistics measurement of the neutrinos from a galactic core-collapse supernova is extremely important for understanding the explosion mechanism, and studying the intrinsic properties of neutrinos themselves. In this paper, we explore the possibility to constrain the absolute scale of neutrino masses m{sub ν} via the detection of galactic supernova neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO) with a 20 kiloton liquid-scintillator detector. In assumption of a nearly-degenerate neutrino mass spectrum and a normal mass ordering, the upper bound on the absolute neutrino mass is found to be m{sub ν}<(0.83±0.24) eV at the 95% confidence level for a typical galactic supernova at a distance of 10 kpc, where the mean value and standard deviation are shown to account for statistical fluctuations. For comparison, we find that the bound in the Super-Kamiokande experiment is m{sub ν}<(0.94±0.28) eV at the same confidence level. However, the upper bound will be relaxed when the model parameters characterizing the time structure of supernova neutrino fluxes are not exactly known, and when the neutrino mass ordering is inverted.

  17. Constraining absolute neutrino masses via detection of galactic supernova neutrinos at JUNO

    SciTech Connect

    Lu, Jia-Shu; Cao, Jun; Li, Yu-Feng; Zhou, Shun E-mail: caoj@ihep.ac.cn E-mail: zhoush@ihep.ac.cn

    2015-05-01

    A high-statistics measurement of the neutrinos from a galactic core-collapse supernova is extremely important for understanding the explosion mechanism, and studying the intrinsic properties of neutrinos themselves. In this paper, we explore the possibility to constrain the absolute scale of neutrino masses m{sub ν} via the detection of galactic supernova neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO) with a 20 kiloton liquid-scintillator detector. In assumption of a nearly-degenerate neutrino mass spectrum and a normal mass ordering, the upper bound on the absolute neutrino mass is found to be m{sub ν} < (0.83 ± 0.24) eV at the 95% confidence level for a typical galactic supernova at a distance of 10 kpc, where the mean value and standard deviation are shown to account for statistical fluctuations. For comparison, we find that the bound in the Super-Kamiokande experiment is m{sub ν} < (0.94 ± 0.28) eV at the same confidence level. However, the upper bound will be relaxed when the model parameters characterizing the time structure of supernova neutrino fluxes are not exactly known, and when the neutrino mass ordering is inverted.

  18. Absolute calorimetric calibration of low energy brachytherapy sources

    NASA Astrophysics Data System (ADS)

    Stump, Kurt E.

    In the past decade there has been a dramatic increase in the use of permanent radioactive source implants in the treatment of prostate cancer. A small radioactive source encapsulated in a titanium shell is used in this type of treatment. The radioisotopes used are generally 125I or 103Pd. Both of these isotopes have relatively short half-lives, 59.4 days and 16.99 days, respectively, and have low-energy emissions and a low dose rate. These factors make these sources well suited for this application, but the calibration of these sources poses significant metrological challenges. The current standard calibration technique involves the measurement of ionization in air to determine the source air-kerma strength. While this has proved to be an improvement over previous techniques, the method has been shown to be metrologically impure and may not be the ideal means of calbrating these sources. Calorimetric methods have long been viewed to be the most fundamental means of determining source strength for a radiation source. This is because calorimetry provides a direct measurement of source energy. However, due to the low energy and low power of the sources described above, current calorimetric methods are inadequate. This thesis presents work oriented toward developing novel methods to provide direct and absolute measurements of source power for low-energy low dose rate brachytherapy sources. The method is the first use of an actively temperature-controlled radiation absorber using the electrical substitution method to determine total contained source power of these sources. The instrument described operates at cryogenic temperatures. The method employed provides a direct measurement of source power. The work presented here is focused upon building a metrological foundation upon which to establish power-based calibrations of clinical-strength sources. To that end instrument performance has been assessed for these source strengths. The intent is to establish the limits of

  19. Upper GI Bleeding in Children

    MedlinePlus

    Upper GI Bleeding in Children What is upper GI Bleeding? Irritation and ulcers of the lining of the esophagus, stomach or duodenum can result in upper GI bleeding. When this occurs the child may vomit ...

  20. Common genetic polymorphisms modify the effect of smoking on absolute risk of bladder cancer

    PubMed Central

    Garcia-Closas, Montserrat; Rothman, Nathaniel; Figueroa, Jonine D.; Prokunina-Olsson, Ludmila; Han, Summer S.; Baris, Dalsu; Jacobs, Eric J; Malats, Nuria; De Vivo, Immaculata; Albanes, Demetrius; Purdue, Mark P; Sharma, Sapna; Fu, Yi-Ping; Kogevinas, Manolis; Wang, Zhaoming; Tang, Wei; Tardón, Adonina; Serra, Consol; Carrato, Alfredo; García-Closas, Reina; Lloreta, Josep; Johnson, Alison; Schwenn, Molly; Karagas, Margaret R; Schned, Alan; Andriole, Gerald; Grubb, Robert; Black, Amanda; Gapstur, Susan M; Thun, Michael; Diver, W Ryan; Weinstein, Stephanie J; Virtamo, Jarmo; Hunter, David J; Caporaso, Neil; Landi, Maria Teresa; Hutchinson, Amy; Burdett, Laurie; Jacobs, Kevin B; Yeager, Meredith; Fraumeni, Joseph F; Chanock, Stephen J; Silverman, Debra T; Chatterjee, Nilanjan

    2013-01-01

    Bladder cancer results from the combined effects of environmental and genetic factors, smoking being the strongest risk factor. Evaluating absolute risks resulting from the joint effects of smoking and genetic factors is critical to evaluate the public health relevance of genetic information. Analyses included up to 3,942 cases and 5,680 controls of European background in seven studies. We tested for multiplicative and additive interactions between smoking and 12 susceptibility loci, individually and combined as a polygenic risk score (PRS). Thirty-year absolute risks and risk differences by levels of the PRS were estimated for US-males aged 50-years. Six out of 12 variants showed significant additive gene-environment interactions, most notably NAT2 (P=7×10-4) and UGT1A6 (P=8×10-4). The 30-year absolute risk of bladder cancer in US males was 6.2% for all current smokers. This risk ranged from 2.9% for current smokers in the lowest quartile of the PRS to 9.9% for current smokers in the upper quartile. Risk difference estimates indicated that 8,200 cases would be prevented if elimination of smoking occurred in 100,000 men in the upper PRS quartile, compared to 2,000 cases prevented by a similar effort in the lowest PRS quartile (P-additive =1×10-4). The impact of eliminating smoking the on number of bladder cancer cases prevented is larger for individuals at higher than lower genetic risk. Our findings could have implications for targeted prevention strategies. However, other smoking-related diseases, as well as practical and ethical considerations, need to be considered before any recommendations could be made. PMID:23536561

  1. Common genetic polymorphisms modify the effect of smoking on absolute risk of bladder cancer.

    PubMed

    Garcia-Closas, Montserrat; Rothman, Nathaniel; Figueroa, Jonine D; Prokunina-Olsson, Ludmila; Han, Summer S; Baris, Dalsu; Jacobs, Eric J; Malats, Nuria; De Vivo, Immaculata; Albanes, Demetrius; Purdue, Mark P; Sharma, Sapna; Fu, Yi-Ping; Kogevinas, Manolis; Wang, Zhaoming; Tang, Wei; Tardón, Adonina; Serra, Consol; Carrato, Alfredo; García-Closas, Reina; Lloreta, Josep; Johnson, Alison; Schwenn, Molly; Karagas, Margaret R; Schned, Alan; Andriole, Gerald; Grubb, Robert; Black, Amanda; Gapstur, Susan M; Thun, Michael; Diver, William Ryan; Weinstein, Stephanie J; Virtamo, Jarmo; Hunter, David J; Caporaso, Neil; Landi, Maria Teresa; Hutchinson, Amy; Burdett, Laurie; Jacobs, Kevin B; Yeager, Meredith; Fraumeni, Joseph F; Chanock, Stephen J; Silverman, Debra T; Chatterjee, Nilanjan

    2013-04-01

    Bladder cancer results from the combined effects of environmental and genetic factors, smoking being the strongest risk factor. Evaluating absolute risks resulting from the joint effects of smoking and genetic factors is critical to assess the public health relevance of genetic information. Analyses included up to 3,942 cases and 5,680 controls of European background in seven studies. We tested for multiplicative and additive interactions between smoking and 12 susceptibility loci, individually and combined as a polygenic risk score (PRS). Thirty-year absolute risks and risk differences by levels of the PRS were estimated for U.S. males aged 50 years. Six of 12 variants showed significant additive gene-environment interactions, most notably NAT2 (P = 7 × 10(-4)) and UGT1A6 (P = 8 × 10(-4)). The 30-year absolute risk of bladder cancer in U.S. males was 6.2% for all current smokers. This risk ranged from 2.9% for current smokers in the lowest quartile of the PRS to 9.9% for current smokers in the upper quartile. Risk difference estimates indicated that 8,200 cases would be prevented if elimination of smoking occurred in 100,000 men in the upper PRS quartile compared with 2,000 cases prevented by a similar effort in the lowest PRS quartile (P(additive) = 1 × 10(-4)). Thus, the potential impact of eliminating smoking on the number of bladder cancer cases prevented is larger for individuals at higher than lower genetic risk. Our findings could have implications for targeted prevention strategies. However, other smoking-related diseases, as well as practical and ethical considerations, need to be considered before any recommendations could be made.

  2. Characterization of the upper respiratory tract microbiomes of patients with pandemic H1N1 influenza.

    PubMed

    Chaban, Bonnie; Albert, Arianne; Links, Matthew G; Gardy, Jennifer; Tang, Patrick; Hill, Janet E

    2013-01-01

    The upper respiratory tract microbiome has an important role in respiratory health. Influenza A is a common viral infection that challenges that health, and a well-recognized sequela is bacterial pneumonia. Given this connection, we sought to characterize the upper respiratory tract microbiota of individuals suffering from the pandemic H1N1 influenza A outbreak of 2009 and determine if microbiome profiles could be correlated with patient characteristics. We determined the microbial profiles of 65 samples from H1N1 patients by cpn60 universal target amplification and sequencing. Profiles were examined at the phylum and nearest neighbor "species" levels using the characteristics of patient gender, age, originating health authority, sample type and designation (STAT/non-STAT). At the phylum level, Actinobacteria-, Firmicutes- and Proteobacteria-dominated microbiomes were observed, with none of the patient characteristics showing significant profile composition differences. At the nearest neighbor "species" level, the upper respiratory tract microbiomes were composed of 13-20 "species" and showed a trend towards increasing diversity with patient age. Interestingly, at an individual level, most patients had one to three organisms dominant in their microbiota. A limited number of discrete microbiome profiles were observed, shared among influenza patients regardless of patient status variables. To assess the validity of analyses derived from sequence read abundance, several bacterial species were quantified by quantitative PCR and compared to the abundance of cpn60 sequence read counts obtained in the study. A strong positive correlation between read abundance and absolute bacterial quantification was observed. This study represents the first examination of the upper respiratory tract microbiome using a target other than the 16S rRNA gene and to our knowledge, the first thorough examination of this microbiome during a viral infection. PMID:23844261

  3. Characterization of the Upper Respiratory Tract Microbiomes of Patients with Pandemic H1N1 Influenza

    PubMed Central

    Chaban, Bonnie; Albert, Arianne; Links, Matthew G.; Gardy, Jennifer; Tang, Patrick; Hill, Janet E.

    2013-01-01

    The upper respiratory tract microbiome has an important role in respiratory health. Influenza A is a common viral infection that challenges that health, and a well-recognized sequela is bacterial pneumonia. Given this connection, we sought to characterize the upper respiratory tract microbiota of individuals suffering from the pandemic H1N1 influenza A outbreak of 2009 and determine if microbiome profiles could be correlated with patient characteristics. We determined the microbial profiles of 65 samples from H1N1 patients by cpn60 universal target amplification and sequencing. Profiles were examined at the phylum and nearest neighbor “species” levels using the characteristics of patient gender, age, originating health authority, sample type and designation (STAT/non-STAT). At the phylum level, Actinobacteria-, Firmicutes- and Proteobacteria-dominated microbiomes were observed, with none of the patient characteristics showing significant profile composition differences. At the nearest neighbor “species” level, the upper respiratory tract microbiomes were composed of 13-20 “species” and showed a trend towards increasing diversity with patient age. Interestingly, at an individual level, most patients had one to three organisms dominant in their microbiota. A limited number of discrete microbiome profiles were observed, shared among influenza patients regardless of patient status variables. To assess the validity of analyses derived from sequence read abundance, several bacterial species were quantified by quantitative PCR and compared to the abundance of cpn60 sequence read counts obtained in the study. A strong positive correlation between read abundance and absolute bacterial quantification was observed. This study represents the first examination of the upper respiratory tract microbiome using a target other than the 16S rRNA gene and to our knowledge, the first thorough examination of this microbiome during a viral infection. PMID:23844261

  4. Scanning micro-resonator direct-comb absolute spectroscopy

    PubMed Central

    Gambetta, Alessio; Cassinerio, Marco; Gatti, Davide; Laporta, Paolo; Galzerano, Gianluca

    2016-01-01

    Direct optical Frequency Comb Spectroscopy (DFCS) is proving to be a fundamental tool in many areas of science and technology thanks to its unique performance in terms of ultra-broadband, high-speed detection and frequency accuracy, allowing for high-fidelity mapping of atomic and molecular energy structure. Here we present a novel DFCS approach based on a scanning Fabry-Pérot micro-cavity resonator (SMART) providing a simple, compact and accurate method to resolve the mode structure of an optical frequency comb. The SMART approach, while drastically reducing system complexity, allows for a straightforward absolute calibration of the optical-frequency axis with an ultimate resolution limited by the micro-resonator resonance linewidth and can be used in any spectral region from UV to THz. We present an application to high-precision spectroscopy of acetylene at 1.54 μm, demonstrating performances comparable or even better than current state-of-the-art DFCS systems in terms of sensitivity, optical bandwidth and frequency-resolution. PMID:27752132

  5. Cosmic backgrounds of relic gravitons and their absolute normalization

    NASA Astrophysics Data System (ADS)

    Giovannini, Massimo

    2014-11-01

    Provided the consistency relations are not violated, the recent BICEP2 observations pin down the absolute normalization, the spectral slope and the maximal frequency of the cosmic graviton background produced during inflation. The properly normalized spectra are hereby computed from the lowest frequencies (of the order of the present Hubble rate) up to the highest frequency range in the GHz region. Deviations from the conventional paradigm cannot be excluded and are examined by allowing for different physical possibilities including, in particular, a running of the tensor spectral index, an explicit breaking of the consistency relations and a spike in the high-frequency tail of the spectrum coming either from a post-inflationary phase dominated by a stiff fluid or from the contribution of waterfall fields in a hybrid inflationary context. The direct determinations of the tensor to scalar ratio at low frequencies, if confirmed by the forthcoming observations, will also affect and constrain the high-frequency uncertainties. The limits on the cosmic graviton backgrounds coming from wide-band interferometers (such as LIGO/Virgo, LISA and BBO/DECIGO) together with a more accurate scrutiny of the tensor B-mode polarization at low frequencies will set direct bounds on the post-inflationary evolution and on other unconventional completions of the standard lore.

  6. Demonstrating the Error Budget for the Climate Absolute Radiance and Refractivity Observatory Through Solar Irradiance Measurements

    NASA Technical Reports Server (NTRS)

    Thome, Kurtis; McCorkel, Joel; McAndrew, Brendan

    2016-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission addresses the need to observe highaccuracy, long-term climate change trends and to use decadal change observations as a method to determine the accuracy of climate change. A CLARREO objective is to improve the accuracy of SI-traceable, absolute calibration at infrared and reflected solar wavelengths to reach on-orbit accuracies required to allow climate change observations to survive data gaps and observe climate change at the limit of natural variability. Such an effort will also demonstrate National Institute of Standards and Technology (NIST) approaches for use in future spaceborne instruments. The current work describes the results of laboratory and field measurements with the Solar, Lunar for Absolute Reflectance Imaging Spectroradiometer (SOLARIS) which is the calibration demonstration system (CDS) for the reflected solar portion of CLARREO. SOLARIS allows testing and evaluation of calibration approaches, alternate design and/or implementation approaches and components for the CLARREO mission. SOLARIS also provides a test-bed for detector technologies, non-linearity determination and uncertainties, and application of future technology developments and suggested spacecraft instrument design modifications. Results of laboratory calibration measurements are provided to demonstrate key assumptions about instrument behavior that are needed to achieve CLARREO's climate measurement requirements. Absolute radiometric response is determined using laser-based calibration sources and applied to direct solar views for comparison with accepted solar irradiance models to demonstrate accuracy values giving confidence in the error budget for the CLARREO reflectance retrieval.

  7. Demonstrating the error budget for the Climate Absolute Radiance and Refractivity Observatory through solar irradiance measurements

    NASA Astrophysics Data System (ADS)

    Thome, Kurtis; McCorkel, Joel; McAndrew, Brendan

    2015-09-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission addresses the need to observe highaccuracy, long-term climate change trends and to use decadal change observations as a method to determine the accuracy of climate change. A CLARREO objective is to improve the accuracy of SI-traceable, absolute calibration at infrared and reflected solar wavelengths to reach on-orbit accuracies required to allow climate change observations to survive data gaps and observe climate change at the limit of natural variability. Such an effort will also demonstrate National Institute of Standards and Technology (NIST) approaches for use in future spaceborne instruments. The current work describes the results of laboratory and field measurements with the Solar, Lunar for Absolute Reflectance Imaging Spectroradiometer (SOLARIS) which is the calibration demonstration system (CDS) for the reflected solar portion of CLARREO. SOLARIS allows testing and evaluation of calibration approaches, alternate design and/or implementation approaches and components for the CLARREO mission. SOLARIS also provides a testbed for detector technologies, non-linearity determination and uncertainties, and application of future technology developments and suggested spacecraft instrument design modifications. Results of laboratory calibration measurements are provided to demonstrate key assumptions about instrument behavior that are needed to achieve CLARREO's climate measurement requirements. Absolute radiometric response is determined using laser-based calibration sources and applied to direct solar views for comparison with accepted solar irradiance models to demonstrate accuracy values giving confidence in the error budget for the CLARREO reflectance retrieval.

  8. Critical inclination for absolute/convective instability transition in inverted falling films

    NASA Astrophysics Data System (ADS)

    Scheid, Benoit; Kofman, Nicolas; Rohlfs, Wilko

    2016-04-01

    Liquid films flowing down the underside of inclined plates are subject to the interaction between the hydrodynamic and the Rayleigh-Taylor (R-T) instabilities causing a patterned and wavy topology at the free surface. The R-T instability results from the denser liquid film being located above a less dense ambient gas, and deforming into an array of droplets, which eventually drip if no saturation mechanism arises. Such saturation mechanism can actually be provided by a fluid motion along the inclined plate. Using a weighted integral boundary layer model, this study examines the critical inclination angle, measured from the vertical, that separates regimes of absolute and convective instability. If the instability is of absolute type, growing perturbations stay localized in space potentially leading to dripping. If the instability is of convective type, growing perturbations move downwards the inclined plate, forming waves and eventually, but not necessarily, droplets. Remarkably, there is a minimum value of the critical angle below which a regime of absolute instability cannot exist. This minimum angle decreases with viscosity: it is about 85° for water, about 70° for silicon oil 20 times more viscous than water, and reaches a limiting value for liquid with a viscosity larger than about 1000 times the one of water. It results that for any fluid, absolute dripping can only exist for inclination angle (taken from the vertical) larger than 57.4°.

  9. Absolute Geodetic Rotation Measurement Using Atom Interferometry

    SciTech Connect

    Stockton, J. K.; Takase, K.; Kasevich, M. A.

    2011-09-23

    We demonstrate a cold-atom interferometer gyroscope which overcomes accuracy and dynamic range limitations of previous atom interferometer gyroscopes. We show how the instrument can be used for precise determination of latitude, azimuth (true north), and Earth's rotation rate. Spurious noise terms related to multiple-path interferences are suppressed by employing a novel time-skewed pulse sequence. Extended versions of this instrument appear capable of meeting the stringent requirements for inertial navigation, geodetic applications of Earth's rotation rate determination, and tests of general relativity.

  10. Improved Mars Upper Atmosphere Climatology

    NASA Technical Reports Server (NTRS)

    Bougher, S. W.

    2004-01-01

    The detailed characterization of the Mars upper atmosphere is important for future Mars aerobraking activities. Solar cycle, seasonal, and dust trends (climate) as well as planetary wave activity (weather) are crucial to quantify in order to improve our ability to reasonably depict the state of the Mars upper atmosphere over time. To date, our best information is found in the Mars Global Surveyor (MGS) Accelerometer (ACC) database collected during Phase 1 (Ls = 184 - 300; F10.7 = 70 - 90) and Phase 2 (Ls = 30 - 90; F10.7 = 90 - 150) of aerobraking. This database (100 - 170 km) consists of thermospheric densities, temperatures, and scale heights, providing our best constraints for exercising the coupled Mars General Circulation Model (MGCM) and the Mars Thermospheric General Circulation Model (MTGCM). The Planetary Data System (PDS) contains level 0 and 2 MGS Accelerometer data, corresponding to atmospheric densities along the orbit track. Level 3 products (densities, temperatures, and scale heights at constant altitudes) are also available in the PDS. These datasets provide the primary model constraints for the new MGCM-MTGCM simulations summarized in this report. Our strategy for improving the characterization of the Mars upper atmospheres using these models has been three-fold : (a) to conduct data-model comparisons using the latest MGS data covering limited climatic and weather conditions at Mars, (b) to upgrade the 15-micron cooling and near-IR heating rates in the MGCM and MTGCM codes for ad- dressing climatic variations (solar cycle and seasonal) important in linking the lower and upper atmospheres (including migrating tides), and (c) to exercise the detailed coupled MGCM and MTGCM codes to capture and diagnose the planetary wave (migrating plus non-migrating tidal) features throughout the Mars year. Products from this new suite of MGCM-MTGCM coupled simulations are being used to improve our predictions of the structure of the Mars upper atmosphere for the

  11. On the Error Sources in Absolute Individual Antenna Calibrations

    NASA Astrophysics Data System (ADS)

    Aerts, Wim; Baire, Quentin; Bilich, Andria; Bruyninx, Carine; Legrand, Juliette

    2013-04-01

    The two main methods for antenna calibration currently in use, are anechoic chamber measurements on the one hand and outdoor robot calibration on the other hand. Both techniques differ completely in approach, setup and data processing. Consequently, the error sources for both techniques are totally different as well. Except for the (near field) multi path error, caused by the antenna positioning device, that alters results for both calibration methods. But not necessarily with the same order of magnitude. Literature states a (maximum deviation) repeatability for robot calibration of choke ring antennas of 0.5 mm on L1 and 1 mm on L2 [1]. For anechoic chamber calibration, a value of 1.5 mm on L2 for a resistive ground plane antenna can be found in [2]. Repeatability however masks systematic errors linked with the calibration technique. Hence, comparing an individual calibration obtained with a robot to a calibration of the same antenna in an anechoic chamber, may result in differences that surpass these repeatability thresholds. This was the case at least for all six choke ring antennas studied. The order of magnitude of the differences moreover corresponded well to the values given for a LEIAT504GG in [3]. For some error sources, such as the GNSS receiver measurement noise or the VNA measurement noise, estimates can be obtained from manufacturer specifications in data sheets. For other error sources, such as the finite distance between transmit and receive antenna, or the limited attenuation of reflections on wall absorber, back-of-the-envelope calculations can be made to estimate their order of magnitude. For the error due to (near field) multi path this is harder to do, if not impossible. The more because this strongly depends on the antenna type and its mount. Unfortunately it is, again, this (near field) multi path influence that might void the calibration once the antenna is installed at the station. Hence it can be concluded that at present, due to (near

  12. Mini-implants and miniplates generate sub-absolute and absolute anchorage

    PubMed Central

    Consolaro, Alberto

    2014-01-01

    The functional demand imposed on bone promotes changes in the spatial properties of osteocytes as well as in their extensions uniformly distributed throughout the mineralized surface. Once spatial deformation is established, osteocytes create the need for structural adaptations that result in bone formation and resorption that happen to meet the functional demands. The endosteum and the periosteum are the effectors responsible for stimulating adaptive osteocytes in the inner and outer surfaces.Changes in shape, volume and position of the jaws as a result of skeletal correction of the maxilla and mandible require anchorage to allow bone remodeling to redefine morphology, esthetics and function as a result of spatial deformation conducted by orthodontic appliances. Examining the degree of changes in shape, volume and structural relationship of areas where mini-implants and miniplates are placed allows us to classify mini-implants as devices of subabsolute anchorage and miniplates as devices of absolute anchorage. PMID:25162561

  13. An All Fiber White Light Interferometric Absolute Temperature Measurement System

    PubMed Central

    Kim, Jeonggon Harrison

    2008-01-01

    Recently the author of this article proposed a new signal processing algorithm for an all fiber white light interferometer. In this article, an all fiber white light interferometric absolute temperature measurement system is presented using the previously proposed signal processing algorithm. Stability and absolute temperature measurement were demonstrated. These two tests demonstrated the feasibility of absolute temperature measurement with an accuracy of 0.015 fringe and 0.0005 fringe, respectively. A hysteresis test from 373K to 873K was also presented. Finally, robustness of the sensor system towards laser diode temperature drift, AFMZI temperature drift and PZT non-linearity was demonstrated.

  14. Measurement of Disintegration Rates and Absolute {gamma}-ray Intensities

    SciTech Connect

    DeVries, Daniel J.; Griffin, Henry C.

    2006-03-13

    The majority of practical radioactive materials decay by modes that include {gamma}-ray emission. For questions of 'how much' or 'how pure', one must know the absolute intensities of the major radiations. We are using liquid scintillation counting (LSC) to measurements of disintegration rates, coupled with {gamma}-ray spectroscopy to measure absolute {gamma}-ray emission probabilities. Described is a study of the 227Th chain yielding absolute {gamma}-ray intensities with {approx}0.5% accuracy and information on LSC efficiencies.

  15. Absolute Antenna Calibration at the US National Geodetic Survey

    NASA Astrophysics Data System (ADS)

    Mader, G. L.; Bilich, A. L.

    2012-12-01

    Geodetic GNSS applications routinely demand millimeter precision and extremely high levels of accuracy. To achieve these accuracies, measurement and instrument biases at the centimeter to millimeter level must be understood. One of these biases is the antenna phase center, the apparent point of signal reception for a GNSS antenna. It has been well established that phase center patterns differ between antenna models and manufacturers; additional research suggests that the addition of a radome or the choice of antenna mount can significantly alter those a priori phase center patterns. For the more demanding GNSS positioning applications and especially in cases of mixed-antenna networks, it is all the more important to know antenna phase center variations as a function of both elevation and azimuth in the antenna reference frame and incorporate these models into analysis software. Determination of antenna phase center behavior is known as "antenna calibration". Since 1994, NGS has computed relative antenna calibrations for more than 350 antennas. In recent years, the geodetic community has moved to absolute calibrations - the IGS adopted absolute antenna phase center calibrations in 2006 for use in their orbit and clock products, and NGS's CORS group began using absolute antenna calibration upon the release of the new CORS coordinates in IGS08 epoch 2005.00 and NAD 83(2011,MA11,PA11) epoch 2010.00. Although NGS relative calibrations can be and have been converted to absolute, it is considered best practice to independently measure phase center characteristics in an absolute sense. Consequently, NGS has developed and operates an absolute calibration system. These absolute antenna calibrations accommodate the demand for greater accuracy and for 2-dimensional (elevation and azimuth) parameterization. NGS will continue to provide calibration values via the NGS web site www.ngs.noaa.gov/ANTCAL, and will publish calibrations in the ANTEX format as well as the legacy ANTINFO

  16. STS upper stage operations

    NASA Technical Reports Server (NTRS)

    Kitchens, M. D.; Schnyer, A. D.

    1977-01-01

    Several design/development and operational approaches for STS upper stages are being pursued to realize maximum operational and economic benefits upon the introduction of the STS in the 1980s. The paper focuses special attention on safety operations, launch site operations and on-orbit operations.

  17. Absolute pitch in infant auditory learning: evidence for developmental reorganization.

    PubMed

    Saffran, J R; Griepentrog, G J

    2001-01-01

    To what extent do infants represent the absolute pitches of complex auditory stimuli? Two experiments with 8-month-old infants examined the use of absolute and relative pitch cues in a tone-sequence statistical learning task. The results suggest that, given unsegmented stimuli that do not conform to the rules of musical composition, infants are more likely to track patterns of absolute pitches than of relative pitches. A 3rd experiment tested adults with or without musical training on the same statistical learning tasks used in the infant experiments. Unlike the infants, adult listeners relied primarily on relative pitch cues. These results suggest a shift from an initial focus on absolute pitch to the eventual dominance of relative pitch, which, it is argued, is more useful for both music and speech processing.

  18. Absolute calibration of sniffer probes on Wendelstein 7-X

    NASA Astrophysics Data System (ADS)

    Moseev, D.; Laqua, H. P.; Marsen, S.; Stange, T.; Braune, H.; Erckmann, V.; Gellert, F.; Oosterbeek, J. W.

    2016-08-01

    Here we report the first measurements of the power levels of stray radiation in the vacuum vessel of Wendelstein 7-X using absolutely calibrated sniffer probes. The absolute calibration is achieved by using calibrated sources of stray radiation and the implicit measurement of the quality factor of the Wendelstein 7-X empty vacuum vessel. Normalized absolute calibration coefficients agree with the cross-calibration coefficients that are obtained by the direct measurements, indicating that the measured absolute calibration coefficients and stray radiation levels in the vessel are valid. Close to the launcher, the stray radiation in the empty vessel reaches power levels up to 340 kW/m2 per MW injected beam power. Furthest away from the launcher, i.e., half a toroidal turn, still 90 kW/m2 per MW injected beam power is measured.

  19. Temporal Dynamics of Microbial Rhodopsin Fluorescence Reports Absolute Membrane Voltage

    PubMed Central

    Hou, Jennifer H.; Venkatachalam, Veena; Cohen, Adam E.

    2014-01-01

    Plasma membrane voltage is a fundamentally important property of a living cell; its value is tightly coupled to membrane transport, the dynamics of transmembrane proteins, and to intercellular communication. Accurate measurement of the membrane voltage could elucidate subtle changes in cellular physiology, but existing genetically encoded fluorescent voltage reporters are better at reporting relative changes than absolute numbers. We developed an Archaerhodopsin-based fluorescent voltage sensor whose time-domain response to a stepwise change in illumination encodes the absolute membrane voltage. We validated this sensor in human embryonic kidney cells. Measurements were robust to variation in imaging parameters and in gene expression levels, and reported voltage with an absolute accuracy of 10 mV. With further improvements in membrane trafficking and signal amplitude, time-domain encoding of absolute voltage could be applied to investigate many important and previously intractable bioelectric phenomena. PMID:24507604

  20. Absolute Value Boundedness, Operator Decomposition, and Stochastic Media and Equations

    NASA Technical Reports Server (NTRS)

    Adomian, G.; Miao, C. C.

    1973-01-01

    The research accomplished during this period is reported. Published abstracts and technical reports are listed. Articles presented include: boundedness of absolute values of generalized Fourier coefficients, propagation in stochastic media, and stationary conditions for stochastic differential equations.