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Observations of Jupiter's nightside airglow (nightglow) and aurora obtained during the flyby of the New Horizons spacecraft show an unexpected lack of ultraviolet nightglow emissions, in contrast to the case during the Voyager flybys in 1979. The flux and average energy of precipitating electrons generally decrease with increasing local time across the nightside, consistent with a possible source region along the dusk flank of Jupiter's magnetosphere. Visible emissions associated with the interaction of Jupiter and its satellite Io extend to a surprisingly high altitude, indicating localized low-energy electron precipitation. These results indicate that the interaction between Jupiter's upper atmosphere and near-space environment is variable and poorly understood; extensive observations of the day side are no guide to what goes on at night.

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[My paper] Norbert Krupp
En route to its ultimate rendezvous with Pluto, the New Horizons spacecraft passed through the magnetic and plasma environment of Jupiter in February 2007. Onboard instruments collected high-resolution images, spectroscopic data, and information about charged particles. The results have revealed unusual structure and variation in Jupiter's plasma and large plasmoids that travel down the magnetotail. Data on Jupiter's aurora provide details of the interaction with the solar wind, and a major volcanic eruption from the moon Io was observed during the encounter.

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Although lightning has been seen on other planets, including Jupiter, polar lightning has been known only on Earth. Optical observations from the New Horizons spacecraft have identified lightning at high latitudes above Jupiter up to 80 degrees N and 74 degrees S. Lightning rates and optical powers were similar at each pole, and the mean optical flux is comparable to that at nonpolar latitudes, which is consistent with the notion that internal heat is the main driver of convection. Both near-infrared and ground-based 5-micrometer thermal imagery reveal that cloud cover has thinned substantially since the 2000 Cassini flyby, particularly in the turbulent wake of the Great Red Spot and in the southern half of the equatorial region, demonstrating that vertical dynamical processes are time-varying on seasonal scales at mid- and low latitudes on Jupiter.
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The dusty jovian ring system must be replenished continuously from embedded source bodies. The New Horizons spacecraft has performed a comprehensive search for kilometer-sized moons within the system, which might have revealed the larger members of this population. No new moons were found, however, indicating a sharp cutoff in the population of jovian bodies smaller than 8-kilometer-radius Adrastea. However, the search revealed two families of clumps in the main ring: one close pair and one cluster of three to five. All orbit within a brighter ringlet just interior to Adrastea. Their properties are very different from those of the few other clumpy rings known; the origin and nonrandom distribution of these features remain unexplained, but resonant confinement by Metis may play a role.
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Science Department, Central Arizona College, Coolidge, Arizona 85128, USA.
Although there are substantial differences between the magnetospheres of Jupiter and Saturn, it has been suggested that cryovolcanic activity at Enceladus could lead to electrodynamic coupling between Enceladus and Saturn like that which links Jupiter with Io, Europa and Ganymede. Powerful field-aligned electron beams associated with the Io-Jupiter coupling, for example, create an auroral footprint in Jupiter's ionosphere. Auroral ultraviolet emission associated with Enceladus-Saturn coupling is anticipated to be just a few tenths of a kilorayleigh (ref. 12), about an order of magnitude dimmer than Io's footprint and below the observable threshold, consistent with its non-detection. Here we report the detection of magnetic-field-aligned ion and electron beams (offset several moon radii downstream from Enceladus) with sufficient power to stimulate detectable aurora, and the subsequent discovery of Enceladus-associated aurora in a few per cent of the scans of the moon's footprint. The footprint varies in emission magnitude more than can plausibly be explained by changes in magnetospheric parameters--and as such is probably indicative of variable plume activity.
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Department of Geriatric Medicine, The Canberra Hospital, PO Box 11, Woden, ACT 2606, Australia. alex.fisher@act.gov.au.
UNLABELLED ABSTRACT: BACKGROUND Data on clinical characteristics and outcomes in regard to hip fracture (HF) type are controversial. This study aimed to evaluate whether clinical and laboratory predictors of poorer outcomes differ by HF type. METHODS Prospective evaluation of 761 consecutively admitted patients (mean age 82.3 ± 8.8 years; 74.9% women) with low-trauma non-pathological HF. Clinical characteristics and short-term outcomes were recorded. Haematological, renal, liver and thyroid status, C-reactive protein, cardiac troponin I, serum 25(OH) vitamin D, PTH, leptin, adiponectin and resistin were determined. RESULTS The cervical compared to the tronchanteric HF group was younger, have higher mean haemoglobin, albumin, adiponectin and resistin and lower PTH levels (all P < 0.05). In-hospital mortality, length of hospital stay (LOS), incidence of post-operative myocardial injury and need of institutionalisation were similar in both groups. Multivariate analysis revealed as independent predictors for in-hospital death in patient with cervical HF male sex, hyperparathyroidism and lower leptin levels, while in patients with trochanteric HF only hyperparathyroidism; for post-operative myocardial injury dementia, smoking and renal impairment in the former group and coronary artery disease (CAD), hyperparathyroidism and hypoleptinaemia in the latter; for LOS > 20 days CAD, and age > 75 years and hyperparathyroidism, respectively. Need of institutionalisation was predicted by age > 75 years and dementia in both groups and also by hypovitaminosis D in the cervical and by hyperparathyroidism in the trochanteric HF. CONCLUSIONS Clinical characteristics and incidence of poorer short-term outcomes in the two main HF types are rather similar but risk factors for certain outcomes are site-specific reflecting differences in underlying mechanisms.
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School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen's Road, Bristol BS8 1RJ, UK.
• Plants have utterly transformed the planet, but testing hypotheses of causality requires a reliable time-scale for plant evolution. While clock methods have been extensively developed, less attention has been paid to the correct interpretation and appropriate implementation of fossil data. • We constructed 17 calibrations, consisting of minimum constraints and soft maximum constraints, for divergences between model representatives of the major land plant lineages. Using a data set of seven plastid genes, we performed a cross-validation analysis to determine the consistency of the calibrations. Six molecular clock analyses were then conducted, one with the original calibrations, and others exploring the impact on divergence estimates of changing maxima at basal nodes, and prior probability densities within calibrations. • Cross-validation highlighted Tracheophyta and Euphyllophyta calibrations as inconsistent, either because their soft maxima were overly conservative or because of undetected rate variation. Molecular clock analyses yielded estimates ranging from 568-815 million yr before present (Ma) for crown embryophytes and from 175-240 Ma for crown angiosperms. • We reject both a post-Jurassic origin of angiosperms and a post-Cambrian origin of land plants. Our analyses also suggest that the establishment of the major embryophyte lineages occurred at a much slower tempo than suggested in most previous studies. These conclusions are entirely compatible with current palaeobotanical data, although not necessarily with their interpretation by palaeobotanists.
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Atmospheric, Oceanic and Planetary Physics, Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK. fletcher@atm.ox.ac.uk
Saturn's slow seasonal evolution was disrupted in 2010-2011 by the eruption of a bright storm in its northern spring hemisphere. Thermal infrared spectroscopy showed that within a month, the resulting planetary-scale disturbance had generated intense perturbations of atmospheric temperatures, winds, and composition between 20° and 50°N over an entire hemisphere (140,000 kilometers). The tropospheric storm cell produced effects that penetrated hundreds of kilometers into Saturn's stratosphere (to the 1-millibar region). Stratospheric subsidence at the edges of the disturbance produced "beacons" of infrared emission and longitudinal temperature contrasts of 16 kelvin. The disturbance substantially altered atmospheric circulation, transporting material vertically over great distances, modifying stratospheric zonal jets, exciting wave activity and turbulence, and generating a new cold anticyclonic oval in the center of the disturbance at 41°N.
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[My paper] Michael W Davis
The Advisory Board Company, USA.
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[My paper] Michael W Davis
Santa Fe, N.M.
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Department of Geriatric Medicine, The Canberra Hospital, ACT, Australia; The Australian National University Medical School, Canberra, ACT, Australia.
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National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Alaska Fisheries Science Center, 2030 Southeast Marine Science Drive, Newport, Oregon 97365, USA.
Fluorescein has been used for rapid and sensitive detection of fish skin and corneal ulceration. Effective use of the fluorescein test requires knowledge of conditions that might cause misleading interpretations or otherwise interfere with test reliability. Examination of fish health and the clinical workup often require tricaine as one of the most commonly used anesthetics. However, tricaine may interfere with correct interpretation of the fluorescein test and might also cause significant fish injury. The effects of tricaine exposure sequence on the fidelity of the fluorescein test was studied in Pacific halibut Hippoglossus stenolepis, walleye pollock Theragra chalcogramma, and northern rock soles Lepidopsetta polyxystra by examining the fluorescence of experimentally induced epidermal wounding. Tricaine can quench fluorescence that is emitted by fluorescein retained in skin ulcers, causing a false-negative reaction. Thus, for the fluorescein test to work properly, it is important to avoid the exposure of fluorescein-treated and rinsed ulcers to tricaine. The effects of exposure to buffered versus unbuffered tricaine on epidermal and corneal integrity were studied in Nile tilapia Oreochromis niloticus and channel catfish Ictalurus punctatus subjected to the fluorescein test and histological examination. Fluorescein could detect not only ulcers but also areas with only a partial loss of epithelium (i.e., erosion). The use of unbuffered tricaine to anesthetize these fish caused serious epidermal and corneal damage. If fish are euthanized with unbuffered tricaine for clinical workup, this severe epidermal or corneal damage could be misinterpreted as an antemortem lesion, leading to misdiagnosis. Even in water with alkalinity exceeding 50 mg/L as CaCO3, it would seem prudent to always buffer tricaine with sodium bicarbonate to prevent a pH change that might lead to iatrogenic effects from unbuffered tricaine. Thus, current general recommendations suggesting that tricaine does not need to be buffered in waters with alkalinity greater than 50 mg/L might need to be modified.

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Science. 2011 Dec 1;:   22144462 
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GEPI, Observatoire de Paris, CNRS, Université Paris Diderot, Place Jules Janssen, 92190, Meudon, France.
Doppler-shifted hydrogen Lyman-alpha (Lyα) emission from galaxies is currently measured and used in cosmology as an indicator of star formation. Until now, the Milky Way emission has not been detected, owing to far brighter local sources, including the H Glow-i.e., solar Lyα radiation backscattered by interstellar atoms that flow within the solar system. Because observations from the Voyager spacecraft, now leaving the heliosphere, are decreasingly affected by the H glow, the Ultraviolet Spectrographs are detecting Lyα diffuse emission from our galaxy. The surface brightness toward nearby star-forming regions is about 3 to 4 Rayleigh. The escape fraction of the radiation from the brightest H II regions is on the order of 3% and is highly spatially variable. These results will help constraining models of Lyα radiation transfer in distant galaxies.
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Science Department, Central Arizona College, Coolidge, Arizona 85128, USA.
Although there are substantial differences between the magnetospheres of Jupiter and Saturn, it has been suggested that cryovolcanic activity at Enceladus could lead to electrodynamic coupling between Enceladus and Saturn like that which links Jupiter with Io, Europa and Ganymede. Powerful field-aligned electron beams associated with the Io-Jupiter coupling, for example, create an auroral footprint in Jupiter's ionosphere. Auroral ultraviolet emission associated with Enceladus-Saturn coupling is anticipated to be just a few tenths of a kilorayleigh (ref. 12), about an order of magnitude dimmer than Io's footprint and below the observable threshold, consistent with its non-detection. Here we report the detection of magnetic-field-aligned ion and electron beams (offset several moon radii downstream from Enceladus) with sufficient power to stimulate detectable aurora, and the subsequent discovery of Enceladus-associated aurora in a few per cent of the scans of the moon's footprint. The footprint varies in emission magnitude more than can plausibly be explained by changes in magnetospheric parameters--and as such is probably indicative of variable plume activity.
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SRI International, Menlo Park, CA, USA. david.huestis@sri.com
Airglow optical emissions from planetary atmospheres provide remotely observable signatures of atmospheric composition, energy deposition processes, and the resulting chemical reactions. We may one day be able to detect airglow emissions from extrasolar planets. Reliable interpretation requires quantitative understanding of the energy sources and chemical mechanisms that produce them. The ultraviolet dayglow observations by the Mariner 6 and 7 (1969) and Mariner 9 (1971-72) motivated numerous modeling studies and laboratory experiments. The most obvious source reaction is photodissociation and photoionization of ambient CO2, which is known in the laboratory to produce the four strong dayglow emitting states: hv + CO2 --> O(1S), CO(a3pi), CO2(+)(A2pi(u)& B2sigma u(+)).(1) If this simplest of models were sufficient, then the high altitude dayglow emissions would all share the same scale height, which would be that of CO2. The few Mariner dayglow observations provide weak statistics. Addition of 4 months of Mars Express dayglow data, and including radio occultation and mass spectrometry data from other missions, have made the analyses and conclusions more robust. The CO(a3pi) and CO2+(B2sigma u(+)) dayglow altitude profiles are consistent with Reaction (1). In contrast, the O(1S) dayglow scale heights are much larger and are consistent with source Reaction (2): O2(+)+ e(-)--> O(1S)(2). Both sets of scale heights change with respect to solar activity roughly as suggested by modeling studies.
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[My paper] R Abbasi, Y Abdou, T Abu-Zayyad, J Adams, J A Aguilar, M Ahlers, K Andeen, J Auffenberg, X Bai, M Baker, S W Barwick, R Bay, J L Bazo Alba, K Beattie, J J Beatty, S Bechet, J K Becker, K-H Becker, M L Benabderrahmane, J Berdermann, P Berghaus, D Berley, E Bernardini, D Bertrand, D Z Besson, M Bissok, E Blaufuss, D J Boersma, C Bohm, O Botner, L Bradley, J Braun, D Breder, M Carson, T Castermans, D Chirkin, B Christy, J Clem, S Cohen, D F Cowen, M V D'Agostino, M Danninger, C T Day, C De Clercq, L Demirörs, O Depaepe, F Descamps, P Desiati, G de Vries-Uiterweerd, T DeYoung, J C Díaz-Vélez, J Dreyer, J P Dumm, M R Duvoort, W R Edwards, R Ehrlich, J Eisch, R W Ellsworth, O Engdegård, S Euler, P A Evenson, O Fadiran, A R Fazely, T Feusels, K Filimonov, C Finley, M M Foerster, B D Fox, A Franckowiak, R Franke, T K Gaisser, J Gallagher, R Ganugapati, L Gerhardt, L Gladstone, A Goldschmidt, J A Goodman, R Gozzini, D Grant, T Griesel, A Gross, S Grullon, R M Gunasingha, M Gurtner, C Ha, A Hallgren, F Halzen, K Han, K Hanson, Y Hasegawa, K Helbing, P Herquet, S Hickford, G C Hill, K D Hoffman, A Homeier, K Hoshina, D Hubert, W Huelsnitz, J-P Hülss, P O Hulth, K Hultqvist, S Hussain, R L Imlay, M Inaba, A Ishihara, J Jacobsen, G S Japaridze, H Johansson, J M Joseph, K-H Kampert, A Kappes, T Karg, A Karle, J L Kelley, N Kemming, P Kenny, J Kiryluk, F Kislat, S R Klein, S Knops, G Kohnen, H Kolanoski, L Köpke, D J Koskinen, M Kowalski, T Kowarik, M Krasberg, T Krings, G Kroll, K Kuehn, T Kuwabara, M Labare, S Lafebre, K Laihem, H Landsman, R Lauer, R Lehmann, D Lennarz, J Lundberg, J Lünemann, J Madsen, P Majumdar, R Maruyama, K Mase, H S Matis, C P McParland, K Meagher, M Merck, P Mészáros, T Meures, E Middell, N Milke, H Miyamoto, T Montaruli, R Morse, S M Movit, R Nahnhauer, J W Nam, P Niessen, D R Nygren, S Odrowski, A Olivas, M Olivo, M Ono, S Panknin, S Patton, L Paul, C Pérez de los Heros, J Petrovic, A Piegsa, D Pieloth, A C Pohl, R Porrata, N Potthoff, P B Price, M Prikockis, G T Przybylski, K Rawlins, P Redl, E Resconi, W Rhode, M Ribordy, A Rizzo, J P Rodrigues, P Roth, F Rothmaier, C Rott, C Roucelle, D Rutledge, B Ruzybayev, D Ryckbosch, H-G Sander, S Sarkar, K Schatto, S Schlenstedt, T Schmidt, D Schneider, A Schukraft, O Schulz, M Schunck, D Seckel, B Semburg, S H Seo, Y Sestayo, S Seunarine, A Silvestri, A Slipak, G M Spiczak, C Spiering, M Stamatikos, T Stanev, G Stephens, T Stezelberger, R G Stokstad, M C Stoufer, S Stoyanov, E A Strahler, T Straszheim, G W Sullivan, Q Swillens, I Taboada, A Tamburro, O Tarasova, A Tepe, S Ter-Antonyan, C Terranova, S Tilav, P A Toale, J Tooker, D Tosi, D Turcan, N van Eijndhoven, J Vandenbroucke, A Van Overloop, J van Santen, B Voigt, C Walck, T Waldenmaier, M Wallraff, M Walter, C Wendt, S Westerhoff, N Whitehorn, K Wiebe, C H Wiebusch, A Wiedemann, G Wikström, D R Williams, R Wischnewski, H Wissing, K Woschnagg, C Xu, X W Xu, G Yodh, S Yoshida
Department of Physics, University of Wisconsin, Madison, Wisconsin 53706, USA.
Point source searches with the IceCube neutrino telescope have been restricted to one hemisphere, due to the exclusive selection of upward going events as a way of rejecting the atmospheric muon background. We show that the region above the horizon can be included by suppressing the background through energy-sensitive cuts. This improves the sensitivity above PeV energies, previously not accessible for declinations of more than a few degrees below the horizon due to the absorption of neutrinos in Earth. We present results based on data collected with 22 strings of IceCube, extending its field of view and energy reach for point source searches. No significant excess above the atmospheric background is observed in a sky scan and in tests of source candidates. Upper limits are reported, which for the first time cover point sources in the southern sky up to EeV energies.
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Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190, China. fuliping@cssar.ac.cn
It is possible to obtain some space weather parameters such as the electron flux and mean energy of the precipitating electrons from the far ultraviolet (FUV) radiance of the aurora observed in a nadir viewing geometry, and the FUV image intensifier is one of the key equipment that used for observation the FUV radiance of the aurora in a nadir viewing geometry. The capability of this equipment will affect the whole purpose of the detection. And the responsibility to the wavelength is the most important parameter of image intensifier. Using the VUV beamline f rom synchrotron radiation as optical source, with PMT and Si-photodiode to detect the optical signal from synchrotron radiation and image intensifier separately, the authors measured the relatively spectral response distribution of our FUV image intensifier from 135 to 250 nm. The measurement result shows that the equipment can work well between 140 and 190 nm and the peak response is near 160 nm, and it can be used for our FUV aurora camera.
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International Foundation for Science, Health, and the Environment, Panorama City, California, USA.
A large density cavity that measured 2000 km across and 500 km in height was observed by DEMETER and Formosat/COSMIC satellites in temporal and spatial relation to a new mode of propagation of electromagnetic (em) pulses between discrete magnetic field-aligned auroral plasmas to high altitudes. Recorded positive plasma potential from satellite probes is consistent with the expulsion of electrons in the creation of density cavities. High-frequency decay spectra support the concept of parametric instabilities fed by free energy sources.
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[My paper] R Erdélyi, V Fedun
The Sun's outer coronal layer exists at a temperature of millions of kelvins, much hotter than the solar surface we observe. How this high temperature is maintained and what energy sources are involved continue to puzzle and fascinate solar researchers. Recently, the Hinode spacecraft was launched to observe and measure the plasma properties of the Sun's outer layers. The data collected by Hinode reveal much about the role of magnetic field interactions and how plasma waves might transport energy to the corona. These results open a new era in high-resolution observation of the Sun.
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We present a combined experimental setup for spin- and angle-resolved direct and inverse photoemission in the vacuum ultraviolet energy range for measurements of the electronic structure below and above the Fermi level. Both techniques are installed in one ultrahigh-vacuum chamber and, as a consequence, allow quasisimultaneous measurements on one and the same sample preparation. The photoemission experiment consists of a gas discharge lamp and an electron energy analyzer equipped with a spin polarization detector based on spin-polarized low-energy electron diffraction. Our homemade inverse-photoemission spectrometer comprises a GaAs photocathode as spin-polarized electron source and Geiger-Muller counters for photon detection at a fixed energy of 9.9 eV. The total energy resolution of the experiment is better than 50 meV for photoemission and better than 200 meV for inverse photoemission. The performance of our combined direct and inverse-photoemission experiment with respect to angular and energy resolutions is exemplified by the Fermi-level crossing of the Cu(111) L-gap surface state. Spin-resolved measurements of Co films on Cu(001) are used to characterize the Sherman function of the spin polarization detector as well as the spin polarization of our electron source.
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The New Horizons (NH) spacecraft observed Io's aurora in eclipse on four occasions during spring 2007. NH Alice ultraviolet spectroscopy and concurrent Hubble Space Telescope ultraviolet imaging in eclipse investigate the relative contribution of volcanoes to Io's atmosphere and its interaction with Jupiter's magnetosphere. Auroral brightness and morphology variations after eclipse ingress and egress reveal changes in the relative contribution of sublimation and volcanic sources to the atmosphere. Brightnesses viewed at different geometries are best explained by a dramatic difference between the dayside and nightside atmospheric density. Far-ultraviolet aurora morphology reveals the influence of plumes on Io's electrodynamic interaction with Jupiter's magnetosphere. Comparisons to detailed simulations of Io's aurora indicate that volcanoes supply 1 to 3% of the dayside atmosphere.
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The New Horizons spacecraft observed Jupiter's icy satellites Europa and Ganymede during its flyby in February and March 2007 at visible and infrared wavelengths. Infrared spectral images map H2O ice absorption and hydrated contaminants, bolstering the case for an exogenous source of Europa's "non-ice" surface material and filling large gaps in compositional maps of Ganymede's Jupiter-facing hemisphere. Visual wavelength images of Europa extend knowledge of its global pattern of arcuate troughs and show that its surface scatters light more isotropically than other icy satellites.
LornaPaul
 

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