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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2010.06.020 Byline: Amy A. Simon-Miller (a), Peter J. Gierasch (b) Keywords: Jupiter, Atmosphere; Atmospheres, Evolution; Atmospheres, Dynamics Abstract: Hubble Space Telescope Wide Field Planetary Camera 2 imaging data of Jupiter were combined with wind profiles from Voyager and Cassini data to study long-term variability in Jupiter's winds and cloud brightness. Searches for evidence of wind velocity periodicity yielded a few latitudes with potential variability; the most significant periods were found nearly symmetrically about the equator at 0[degrees], 10-12[degrees]N, and 14-18[degrees]S planetographic latitude. The low to mid-latitude signals have components consistent with the measured stratospheric temperature Quasi-Quadrennial Oscillation (QQO) period of 4-5years, while the equatorial signal is approximately seasonal and could be tied to mesoscale wave formation. Robustness tests indicate that a constant or continuously varying periodic signal near 4.5years would appear with high significance in the data periodograms as long as uncertainties or noise in the data are not of greater magnitude. However, the lack of a consistent signal over many latitudes makes it difficult to interpret as a QQO-related change. In addition, further analyses of calibrated 410-nm and 953-nm brightness scans found few corresponding changes in troposphere haze and cloud structure on QQO timescales. However, stratospheric haze reflectance at 255-nm did appear to vary on seasonal timescales, though the data do not have enough temporal coverage or photometric accuracy to be conclusive. Sufficient temporal coverage and spacing, as well as data quality, are critical to this type of search. Author Affiliation: (a) Code 693, NASA Goddard Space Flight Center, Greenbelt, MD 20771, United States (b) 318 Space Sciences Department, Cornell University, Ithaca, NY 14853, United States Article History: Received 19 March 2010; Revised 16 June 2010; Accepted 16 June 2010

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2010.06.044 Byline: Michael G. Sussman (a), Nancy J. Chanover (a), Amy A. Simon-Miller (b), Ashwin R. Vasavada (c), Reta F. Beebe (a) Keywords: Atmospheres, Dynamics; Jupiter, Atmosphere; Data reduction techniques Abstract: We present a novel method of constructing streamlines to derive wind speeds within jovian vortices and demonstrate its application to Oval BA for 2001 pre-reddened Cassini flyby data, 2007 post-reddened New Horizons flyby data, and 1998 Galileo data of precursor Oval DE. Our method, while automated, attempts to combine the advantages of both automated and manual cloud tracking methods. The southern maximum wind speed of Oval BA does not show significant changes between these data sets to within our measurement uncertainty. The northern maximum does appear to have increased in strength during this time interval, which likely correlates with the oval's return to a symmetric shape. We demonstrate how the use of closed streamlines can provide measurements of vorticity averaged over the encircled area with no a priori assumptions concerning oval shape. We find increased averaged interior vorticity between pre- and post-reddened Oval BA, with the precursor Oval DE occupying a middle value of vorticity between these two. Author Affiliation: (a) New Mexico State University, Dept. of Astronomy, PO Box 30001, MSC 4500, Las Cruces, NM 88003-8001, USA (b) NASA/GSFC, Code 693, Greenbelt, MD 20771, USA (c) Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109, USA Article History: Received 16 June 2009; Revised 23 June 2010; Accepted 24 June 2010

The case of a 73-year-old man with a 6-month history of progressive, symmetric edema and dyspnea on exertion is discussed to arrive at a better understanding of the complications involved in arriving at a correct diagnosis of senile amyloidosis. The different treatment methodologies and management regime are highlighted.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2009.04.002 Byline: Sandrine Guerlet (a), Thierry Fouchet (a), Bruno Bezard (a), Amy A. Simon-Miller (b), F. Michael Flasar (b) Keywords: Saturn; Infrared observations; Atmospheres; Composition Abstract: Measuring the spatial distribution of chemical compounds in Saturn's stratosphere is critical to better understand the planet's photochemistry and dynamics. Here we present an analysis of infrared spectra in the range 600-1400cm.sup.-1 acquired in limb geometry by the Cassini spacecraft between March 2005 and January 2008. We first determine the vertical temperature profiles from 3 to 0.01hPa, at latitudes ranging from 70[degrees]N to 80[degrees]S. We infer a similar meridional temperature gradient at 1-2hPa as in recent previous studies [Fletcher, L.N., Irwin, P.G.J., Teanby, N.A., Orton, G.S., Parrish, P.D., de Kok, R., Howett, C., Calcutt, S.B., Bowles, N., Taylor, F.W., 2007. Icarus 189, 457-478; Howett, C.J.A., Irwin, P.G.J., Teanby, N.A., Simon-Miller, A., Calcutt, S.B., Fletcher, L.N., de Kok, R., 2007. Icarus 190, 556-572]. We then retrieve the vertical profiles of C.sub.2H.sub.6 and C.sub.2H.sub.2 from 3 to 0.01hPa and of C.sub.3H.sub.8 around 1hPa. At 1hPa, the meridional variation of C.sub.2H.sub.2 is found to follow the yearly averaged solar insolation, except for a strong equatorial mole fraction of 8x10.sup.-7, nearly two times higher than expected. This enhancement in abundance can be explained by the descent of hydrocarbon-rich air, with a vertical wind speed at the equator of 0.25[+ or -]0.1 mm/s at 1hPa and 0.4[+ or -]0.15 mm/s at 0.1hPa. The ethane distribution is relatively uniform at 1hPa, with only a moderate 25% increase from 35[degrees]S to 80[degrees]S. Propane is found to increase from north to south by a factor of 1.9, suggesting that its lifetime may be shorter than Saturn's year at 1hPa. At high altitudes (1Pa), C.sub.2H.sub.2 and C.sub.2H.sub.6 abundances depart significantly from the photochemical model predictions of Moses and Greathouse [Moses, J.I., Greathouse, T.K., 2005. J. Geophys. Res. 110, 9007], except at high southern latitudes (62, 70 and 80[degrees]S) and near the equator. The observed abundances are found strongly depleted in the 20-40[degrees]S region and enhanced in the 20-30[degrees]N region, the latter coinciding with the ring's shadow. We favor a dynamical explanation for these anomalies. Author Affiliation: (a) LESIA - Observatoire de Paris, 92195 Meudon, France (b) NASA/Goddard Space Flight Center, Code 693, Greenbelt, MD 20771, USA Article History: Received 18 December 2008; Revised 3 April 2009; Accepted 13 April 2009

The C[O.sub.2]-concentrating mechanism (CCM) of Chlamydomonas reinhardtii and other microalgal species is essential for photosynthetic growth in most natural settings. A great deal has been learned regarding the CCM in cyanobacteria, including identification of inorganic carbon (Ci; C[O.sub.2] and HC[O.sup.-.sub.3]) transporters; however, specific knowledge of analogous transporters has remained elusive in eukaryotic microalgae such as C. reinhardtii. Here we investigated whether the limiting-C[O.sub.2]--inducible, putative ABC-type transporter HLA3 might function as a HC[O.sup.-.sub.3] transporter by evaluating the effect of pH on growth, photosynthetic Ci affinity, and [[sup.14]C]-Ci uptake in very low C[O.sub.2] conditions following RNA interference (RNAi) knockdown of HLA3 mRNA levels in wild-type and mutant cells. Although knockdown of HLA3 mRNA alone resulted in only modest but high-pH--dependent decreases in photosynthetic Ci affinity and Ci uptake, the combination of nearly complete knockdown of HLA3 mRNA with mutations in LCIB (which encodes limiting-Ci--inducible plastid-localized protein required for normal Ci uptake or accumulation in low-C[O.sub.2] conditions) and/or simultaneous, apparently off-target knockdown of LCIA mRNA (which encodes limiting-Ci--inducible plastid envelope protein reported to transport HC[O.sup.-.sub.3]) resulted in dramatic decreases in growth, Ci uptake, and photosynthetic Ci affinity, especially at pH 9, at which HC[O.sup.-.sub.3] is the predominant form of available Ci. Collectively, the data presented here provide compelling evidence that HLA3 is directly or indirectly involved in HC[O.sup.-.sub.3] transport, along with additional evidence supporting a role for LCIA in chloroplast envelope HC[O.sup.-.sub.3] transport and a role for LCIB in chloroplast Ci accumulation. ABC transporter | C[O.sub.2]-concentrating mechanism | microalgae | RNAi

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1475-682X.2008.00272.x Byline: Amy Chasteen Miller (1) Abstract: Most pregnant women in the United States today choose a normative physician-guided pregnancy followed by a medically managed hospital birth. Some, however, choose the care of a midwife during pregnancy and birth, whether in the hospital or, more rarely, at home. Despite growing research on both these paths, a third option chosen by some women has rarely been studied: a planned birth at home with neither a doctor nor a midwife assisting. In this article, I examine the stories told by women in this under-researched population to consider how they make and explain this highly unusual choice. Analysis of online birth stories and in-depth interviews with women who planned and had an unassisted homebirth reveal ways in which these women rely on competing discourses of midwifery and medicine to craft a unique sense of agency in birth. Author Affiliation: (1)University of Southern Mississippi

The availability of the complete DNA sequence of the Chlamydomonas reinhardtii genome and advanced computational biology tools has allowed elucidation and study of the small ubiquitin-like modifier (SUMO) system in this unicellular photosynthetic alga and model eukaryotic cell system. SUMO is a member of a ubiquitin-like protein superfamily that is covalently attached to target proteins as a post-translational modification to alter the localization, stability, and/or function of the target protein in response to changes in the cellular environment. Three SUMO homologs (CrSUMO96, CrSUMO97, and CrSUMO148) and three novel SUMO-related proteins (CrSUMO-like89A, CrSUMO-like89B, and CrSUMO-like90) were found by diverse gene predictions, hidden Markov models, and database search tools inferring from Homo sapiens, Saccharomyces cerevisiae, and Arabidopsis thaliana SUMOs. Among them, CrSUMO96, which can be recognized by the A. thaliana anti-SUMO1 antibody, was studied in detail. Free CrSUMO96 was purified by immunoprecipitation and identified by mass spectrometry analysis. A SUMO-conjugating enzyme (SCE) (E2, Ubc9) in C. reinhardtii was shown to be functional in an Escherichia coli-based in vivo chimeric SUMOylation system. Antibodies to CrSUMO96 recognized free and conjugated forms of CrSUMO96 in Western blot analysis of whole-cell extracts and nuclear localized SUMOylated proteins with in situ immunoflnorescence. Western blot analysis showed a marked increase in SUMO conjugated proteins when the cells were subjected to environmental stresses, such as heat shock and osmotic stress. Related analyses revealed multiple potential ubiquitin genes along with two Rub1 genes and one Ufm1 gene in the C. reinhardtii genome.

Abstract: Long-term studies in Alaska have demonstrated that bears may capture and carry to the riparian forest a large number of salmon that return to spawn in small freshwater streams. [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2006.08.009 Byline: Amy A. Simon-Miller (a), Bradley W. Poston (b), Glenn S. Orton (c), Brendan Fisher (c) Keywords: Jupiter; atmosphere; Atmospheres; dynamics; Infrared observations Abstract: Jupiter's equatorial atmosphere, much like the Earth's, is known to show quasi-periodic variations in temperature, particularly in the stratosphere, but variations in other jovian atmospheric tracers have not been studied for any correlations to these oscillations. Data taken at NASA's Infrared Telescope Facility (IRTF) from 1979 to 2000 were used to obtain temperatures at two levels in the atmosphere, corresponding to the upper troposphere (250 mbar) and to the stratosphere (20 mbar). We find that the data show periodic signals at latitudes corresponding to the troposphere zonal wind jets, with periods ranging from 4.4 (stratosphere, 95% confidence at 4[degrees] S planetographic latitude) to 7.7 years (troposphere, 97% confidence at 6[degrees] N). We also discuss evidence that at some latitudes the troposphere temperature variations are out of phase from the stratosphere variations, even where no periodicity is evident. Hubble Space Telescope images were used, in conjunction with Voyager and Cassini data, to track small changes in the troposphere zonal winds from 20[degrees] N to 20[degrees] S latitude over the 1994-2000 time period. Oscillations with a period of 4.5 years are found near 7[degrees]-8[degrees] S, with 80-85% significance. Further, the strongest evidence for a QQO-induced tropospheric wind change tied to stratospheric temperature change occurs near these latitudes, though tropospheric temperatures show little periodicity here. Comparison of thermal winds and measured zonal winds for three dates indicate that cloud features at other latitudes are likely tracked at pressures that can vary by up to a few hundred millibar, but the cloud altitude change required is too large to explain the wind changes measured at 7[degrees] S. Author Affiliation: (a) NASA's Goddard Space Flight Center, Code 693.0, Greenbelt, MD 20771, USA (b) University of Maryland College Park, 1208B Cambridge Hall, College Park, MD 20742, USA (c) Jet Propulsion Laboratory, 4800 Oak Grove Road, M/S 169-237, Pasadena, CA 91109, USA Article History: Received 24 February 2006; Revised 3 August 2006

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.icarus.2006.08.002 Byline: Amy A. Simon-Miller (a), Nancy J. Chanover (b), Glenn S. Orton (c), Michael Sussman (b), Irene G. Tsavaris (d), Erich Karkoschka (e) Keywords: Jupiter, atmosphere; Atmospheres, dynamics Abstract: Jupiter's remaining White Oval changed color in late 2005 and became noticeably red in early 2006, as reported by amateur observers. We present wind and color analyses from high spatial resolution images taken with the Hubble Space Telescope Advanced Camera for Surveys in April 2006. These images suggest that the recent color change was tied to a strengthening of this storm, as implied by increased vorticity, causing it to become more like the Great Red Spot. From a historical perspective, the current activity may be consistent with the generation of new anticyclones at this latitude in the coming months and years. Author Affiliation: (a) NASA Goddard Space Flight Center, Code 693.0, Greenbelt, MD 20771, USA (b) New Mexico State University, P.O. Box 30001, MSC 4500, Las Cruces, NM 88003, USA (c) Jet Propulsion Laboratory, 4800 Oak Grove Road, M/S 169-237, Pasadena, CA 91109, USA (d) University of Maryland, College Park Scholars, 1208B Cumberland Hall, College Park, MD 20742, USA (e) Department of Planetary Sciences & Lunar and Planetary Laboratory, University of Arizona, 1629 E. University Blvd., Tucson, AZ 85721, USA Article History: Received 9 May 2006; Revised 7 August 2006 Article Note: (footnote) [star] Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with programs GO10192, GO10782 and GO10783.

The Cassini Imaging Science Subsystem (ISS) and Composite Infrared Spectrometer (CIRS) reported a North Equatorial Belt (NEB) wave in Jupiter's atmosphere from optical images [Porco, C.C., and 23 colleagues, 2003. Science 299, 1541-1547] and thermal maps [Flasar, EM., and 39 colleagues, 2004. Nature 427, 132-135], respectively. The connection between the two waves remained uncertain because the two observations were not simultaneous. Here we report on simultaneous ISS images and CIRS thermal maps that confirm that the NEB wave shown in the ISS ultraviolet (UV1) and strong methane band (MT3) images is correlated with the thermal wave in the CIRS temperature maps, with low temperatures in the CIRS maps (upwelling) corresponding to dark regions in the UV1 images (UV-absorbing particles) and bright regions in the MT3 images (high clouds and haze). The long period of the NEB wave suggests that it is a planetary (Rossby) wave. The combined observations from the ISS and CIRS are utilized to discuss the vertical and meridional propagation of the NEB wave, which offers a possible explanation for why the NEB wave is confined to specific latitudes and altitudes. Further, the ISS UV1 images reveal a circumpolar wave centered at 48.5[degrees] S (planetocentric) and probably located in the stratosphere, as suggested by the ISS and CIRS observations. The simultaneous comparison between the ISS and CIRS also implies that the large dark oval in the polar stratosphere of Jupiter discovered in the ISS UV1 images [Porco, C.C., and 23 colleagues, 2003. Science 299, 1541-1547] is the same feature as the warm regions at high northern latitudes in the CIRS 1-mbar temperature maps [Flasar, EM., and 39 colleagues, 2004. Nature 427, 132-135]. This comparison supports a previous suggestion that the dark oval in the ISS UV1 images is linked to auroral precipitation and heating [Porco, C.C., and 23 colleagues, 2003. Science 299, 1541-1547]. Keywords: Atmospheres, dynamics; Jupiter, atmosphere; Planetary dynamics

Retrievals performed on Cassini Composite Infrared Spectrometer data obtained during the distant Jupiter flyby in 2000/2001 have been used to generate global temperature maps of the planet in the troposphere and stratosphere, but to higher latitudes than were shown previously by Flasar et al. [Flasar, F.M., 39 colleagues, 2004a. Nature 427, 132-135, Flasar, F.M., 44 colleagues, 2004b. Space Sci. Rev. 115, 169-297]. Similar retrievals were performed on Voyager 1 IRIS data to provide the first detailed IRIS map of the stratosphere, and high latitudes in the troposphere. Thermal winds were calculated for each data set and show strong vertical shears in the zonal winds at low latitudes, and meridional temperature gradients indicate the presence of circumpolar jets, as well. The temperatures retrieved from the two spacecraft were also compared with yearly ground-based data obtained over the intervening two decades. Tropospheric temperatures reveal gradual changes at low latitudes, with little obvious seasonal or short-term variation [Orton et al., 1994. Science 265, 625-631]. Stratospheric temperatures show much more complicated behavior over short timescales, consistent with quasi-quadrennial oscillations at low latitudes, as suggested in prior analyses of shorter intervals of ground-based data [Orton et al., 1991. Science 252, 537-542; Friedson, A.J., 1999. Icarus 137, 34-55]. A scaling analysis indicates that meridional motions, mechanically forced by wave or eddy convergence, play an important role in modulating the temperatures and winds in the upper troposphere and stratosphere on seasonal and shorter timescales. At latitudes away from the equator, the mechanical forcing can be derived simply from a temporal record of temperature and its vertical derivative. Ground-based observations with improved vertical resolution and/or long-term monitoring from spacecraft are required for this purpose, though the Voyager and Cassini data given indications that the magnitude of the forcing is very small. Keywords: Jupiter, atmosphere; Atmospheres, dynamics; Atmospheres, temperature